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diff --git a/openssl/doc/ssleay.txt b/openssl/doc/ssleay.txt deleted file mode 100644 index c9b29bd..0000000 --- a/openssl/doc/ssleay.txt +++ /dev/null @@ -1,7030 +0,0 @@ - -Bundle of old SSLeay documentation files [OBSOLETE!] - -*** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! *** - -OBSOLETE means that nothing in this document should be trusted. This -document is provided mostly for historical purposes (it wasn't even up -to date at the time SSLeay 0.8.1 was released) and as inspiration. If -you copy some snippet of code from this document, please _check_ that -it really is correct from all points of view. For example, you can -check with the other documents in this directory tree, or by comparing -with relevant parts of the include files. - -People have done the mistake of trusting what's written here. Please -don't do that. - -*** WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! WARNING! *** - - -==== readme ======================================================== - -This is the old 0.6.6 docuementation. Most of the cipher stuff is still -relevent but I'm working (very slowly) on new documentation. -The current version can be found online at - -http://www.cryptsoft.com/ssleay/doc - -==== API.doc ======================================================== - -SSL - SSLv2/v3/v23 etc. - -BIO - methods and how they plug together - -MEM - memory allocation callback - -CRYPTO - locking for threads - -EVP - Ciphers/Digests/signatures - -RSA - methods - -X509 - certificate retrieval - -X509 - validation - -X509 - X509v3 extensions - -Objects - adding object identifiers - -ASN.1 - parsing - -PEM - parsing - -==== ssl/readme ===================================================== - -22 Jun 1996 -This file belongs in ../apps, but I'll leave it here because it deals -with SSL :-) It is rather dated but it gives you an idea of how -things work. -=== - -17 Jul 1995 -I have been changing things quite a bit and have not fully updated -this file, so take what you read with a grain of salt -eric -=== -The s_client and s_server programs can be used to test SSL capable -IP/port addresses and the verification of the X509 certificates in use -by these services. I strongly advise having a look at the code to get -an idea of how to use the authentication under SSLeay. Any feedback -on changes and improvements would be greatly accepted. - -This file will probably be gibberish unless you have read -rfc1421, rfc1422, rfc1423 and rfc1424 which describe PEM -authentication. - -A Brief outline (and examples) how to use them to do so. - -NOTE: -The environment variable SSL_CIPER is used to specify the prefered -cipher to use, play around with setting it's value to combinations of -RC4-MD5, EXP-RC4-MD5, CBC-DES-MD5, CBC3-DES-MD5, CFB-DES-NULL -in a : separated list. - -This directory contains 3 X509 certificates which can be used by these programs. -client.pem: a file containing a certificate and private key to be used - by s_client. -server.pem :a file containing a certificate and private key to be used - by s_server. -eay1024.pem:the certificate used to sign client.pem and server.pem. - This would be your CA's certificate. There is also a link - from the file a8556381.0 to eay1024.PEM. The value a8556381 - is returned by 'x509 -hash -noout <eay1024.pem' and is the - value used by X509 verification routines to 'find' this - certificte when search a directory for it. - [the above is not true any more, the CA cert is - ../certs/testca.pem which is signed by ../certs/mincomca.pem] - -When testing the s_server, you may get -bind: Address already in use -errors. These indicate the port is still being held by the unix -kernel and you are going to have to wait for it to let go of it. If -this is the case, remember to use the port commands on the s_server and -s_client to talk on an alternative port. - -===== -s_client. -This program can be used to connect to any IP/hostname:port that is -talking SSL. Once connected, it will attempt to authenticate the -certificate it was passed and if everything works as expected, a 2 -directional channel will be open. Any text typed will be sent to the -other end. type Q<cr> to exit. Flags are as follows. --host arg : Arg is the host or IP address to connect to. --port arg : Arg is the port to connect to (https is 443). --verify arg : Turn on authentication of the server certificate. - : Arg specifies the 'depth', this will covered below. --cert arg : The optional certificate to use. This certificate - : will be returned to the server if the server - : requests it for client authentication. --key arg : The private key that matches the certificate - : specified by the -cert option. If this is not - : specified (but -cert is), the -cert file will be - : searched for the Private key. Both files are - : assumed to be in PEM format. --CApath arg : When to look for certificates when 'verifying' the - : certificate from the server. --CAfile arg : A file containing certificates to be used for - : 'verifying' the server certificate. --reconnect : Once a connection has been made, drop it and - : reconnect with same session-id. This is for testing :-). - -The '-verify n' parameter specifies not only to verify the servers -certificate but to also only take notice of 'n' levels. The best way -to explain is to show via examples. -Given -s_server -cert server.PEM is running. - -s_client - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify error:num=1:unable to get issuer certificate - verify return:1 - CIPHER is CBC-DES-MD5 -What has happened is that the 'SSLeay demo server' certificate's -issuer ('CA') could not be found but because verify is not on, we -don't care and the connection has been made anyway. It is now 'up' -using CBC-DES-MD5 mode. This is an unauthenticate secure channel. -You may not be talking to the right person but the data going to them -is encrypted. - -s_client -verify 0 - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify error:num=1:unable to get issuer certificate - verify return:1 - CIPHER is CBC-DES-MD5 -We are 'verifying' but only to depth 0, so since the 'SSLeay demo server' -certificate passed the date and checksum, we are happy to proceed. - -s_client -verify 1 - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify error:num=1:unable to get issuer certificate - verify return:0 - ERROR - verify error:unable to get issuer certificate -In this case we failed to make the connection because we could not -authenticate the certificate because we could not find the -'CA' certificate. - -s_client -verify 1 -CAfile eay1024.PEM - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 -We loaded the certificates from the file eay1024.PEM. Everything -checked out and so we made the connection. - -s_client -verify 1 -CApath . - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 -We looked in out local directory for issuer certificates and 'found' -a8556381.0 and so everything is ok. - -It is worth noting that 'CA' is a self certified certificate. If you -are passed one of these, it will fail to 'verify' at depth 0 because -we need to lookup the certifier of a certificate from some information -that we trust and keep locally. - -SSL_CIPHER=CBC3-DES-MD5:RC4-MD5 -export SSL_CIPHER -s_client -verify 10 -CApath . -reconnect - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - drop the connection and reconnect with the same session id - CIPHER is CBC3-DES-MD5 -This has done a full connection and then re-estabished it with the -same session id but a new socket. No RSA stuff occures on the second -connection. Note that we said we would prefer to use CBC3-DES-MD5 -encryption and so, since the server supports it, we are. - -===== -s_server -This program accepts SSL connections on a specified port -Once connected, it will estabish an SSL connection and optionaly -attempt to authenticate the client. A 2 directional channel will be -open. Any text typed will be sent to the other end. Type Q<cr> to exit. -Flags are as follows. --port arg : Arg is the port to listen on. --verify arg : Turn on authentication of the client if they have a - : certificate. Arg specifies the 'depth'. --Verify arg : Turn on authentication of the client. If they don't - : have a valid certificate, drop the connection. --cert arg : The certificate to use. This certificate - : will be passed to the client. If it is not - : specified, it will default to server.PEM --key arg : The private key that matches the certificate - : specified by the -cert option. If this is not - : specified (but -cert is), the -cert file will be - : searched for the Private key. Both files are - : assumed to be in PEM format. Default is server.PEM --CApath arg : When to look for certificates when 'verifying' the - : certificate from the client. --CAfile arg : A file containing certificates to be used for - : 'verifying' the client certificate. - -For the following 'demo' I will specify the s_server command and -the s_client command and then list the output from the s_server. -s_server -s_client - CONNECTED - CIPHER is CBC-DES-MD5 -Everything up and running - -s_server -verify 0 -s_client - CONNECTED - CIPHER is CBC-DES-MD5 -Ok since no certificate was returned and we don't care. - -s_server -verify 0 -./s_client -cert client.PEM - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client - issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify error:num=1:unable to get issuer certificate - verify return:1 - CIPHER is CBC-DES-MD5 -Ok since we were only verifying to level 0 - -s_server -verify 4 -s_client -cert client.PEM - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client - issuer= /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify error:num=1:unable to get issuer certificate - verify return:0 - ERROR - verify error:unable to get issuer certificate -Bad because we could not authenticate the returned certificate. - -s_server -verify 4 -CApath . -s_client -cert client.PEM - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 -Ok because we could authenticate the returned certificate :-). - -s_server -Verify 0 -CApath . -s_client - CONNECTED - ERROR - SSL error:function is:REQUEST_CERTIFICATE - :error is :client end did not return a certificate -Error because no certificate returned. - -s_server -Verify 4 -CApath . -s_client -cert client.PEM - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 -Full authentication of the client. - -So in summary to do full authentication of both ends -s_server -Verify 9 -CApath . -s_client -cert client.PEM -CApath . -verify 9 -From the server side - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo client - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 -From the client side - CONNECTED - depth=0 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=SSLeay demo server - verify return:1 - depth=1 /C=AU/SOP=QLD/O=Mincom Pty. Ltd./OU=CS/CN=CA - verify return:1 - CIPHER is CBC-DES-MD5 - -For general probing of the 'internet https' servers for the -distribution area, run -s_client -host www.netscape.com -port 443 -verify 4 -CApath ../rsa/hash -Then enter -GET / -and you should be talking to the https server on that host. - -www.rsa.com was refusing to respond to connections on 443 when I was -testing. - -have fun :-). - -eric - -==== a_verify.doc ======================================================== - -From eay@mincom.com Fri Oct 4 18:29:06 1996 -Received: by orb.mincom.oz.au id AA29080 - (5.65c/IDA-1.4.4 for eay); Fri, 4 Oct 1996 08:29:07 +1000 -Date: Fri, 4 Oct 1996 08:29:06 +1000 (EST) -From: Eric Young <eay@mincom.oz.au> -X-Sender: eay@orb -To: wplatzer <wplatzer@iaik.tu-graz.ac.at> -Cc: Eric Young <eay@mincom.oz.au>, SSL Mailing List <ssl-users@mincom.com> -Subject: Re: Netscape's Public Key -In-Reply-To: <19961003134837.NTM0049@iaik.tu-graz.ac.at> -Message-Id: <Pine.SOL.3.91.961004081346.8018K-100000@orb> -Mime-Version: 1.0 -Content-Type: TEXT/PLAIN; charset=US-ASCII -Status: RO -X-Status: - -On Thu, 3 Oct 1996, wplatzer wrote: -> I get Public Key from Netscape (Gold 3.0b4), but cannot do anything -> with it... It looks like (asn1parse): -> -> 0:d=0 hl=3 l=180 cons: SEQUENCE -> 3:d=1 hl=2 l= 96 cons: SEQUENCE -> 5:d=2 hl=2 l= 92 cons: SEQUENCE -> 7:d=3 hl=2 l= 13 cons: SEQUENCE -> 9:d=4 hl=2 l= 9 prim: OBJECT :rsaEncryption -> 20:d=4 hl=2 l= 0 prim: NULL -> 22:d=3 hl=2 l= 75 prim: BIT STRING -> 99:d=2 hl=2 l= 0 prim: IA5STRING : -> 101:d=1 hl=2 l= 13 cons: SEQUENCE -> 103:d=2 hl=2 l= 9 prim: OBJECT :md5withRSAEncryption -> 114:d=2 hl=2 l= 0 prim: NULL -> 116:d=1 hl=2 l= 65 prim: BIT STRING -> -> The first BIT STRING is the public key and the second BIT STRING is -> the signature. -> But a public key consists of the public exponent and the modulus. Are -> both numbers in the first BIT STRING? -> Is there a document simply describing this coding stuff (checking -> signature, get the public key, etc.)? - -Minimal in SSLeay. If you want to see what the modulus and exponent are, -try asn1parse -offset 25 -length 75 <key.pem -asn1parse will currently stuff up on the 'length 75' part (fixed in next -release) but it will print the stuff. If you are after more -documentation on ASN.1, have a look at www.rsa.com and get their PKCS -documents, most of my initial work on SSLeay was done using them. - -As for SSLeay, -util/crypto.num and util/ssl.num are lists of all exported functions in -the library (but not macros :-(. - -The ones for extracting public keys from certificates and certificate -requests are EVP_PKEY * X509_REQ_extract_key(X509_REQ *req); -EVP_PKEY * X509_extract_key(X509 *x509); - -To verify a signature on a signed ASN.1 object -int X509_verify(X509 *a,EVP_PKEY *key); -int X509_REQ_verify(X509_REQ *a,EVP_PKEY *key); -int X509_CRL_verify(X509_CRL *a,EVP_PKEY *key); -int NETSCAPE_SPKI_verify(NETSCAPE_SPKI *a,EVP_PKEY *key); - -I should mention that EVP_PKEY can be used to hold a public or a private key, -since for things like RSA and DSS, a public key is just a subset of what -is stored for the private key. - -To sign any of the above structures - -int X509_sign(X509 *a,EVP_PKEY *key,EVP_MD *md); -int X509_REQ_sign(X509_REQ *a,EVP_PKEY *key,EVP_MD *md); -int X509_CRL_sign(X509_CRL *a,EVP_PKEY *key,EVP_MD *md); -int NETSCAPE_SPKI_sign(NETSCAPE_SPKI *a,EVP_PKEY *key,EVP_MD *md); - -where md is the message digest to sign with. - -There are all defined in x509.h and all the _sign and _verify functions are -actually macros to the ASN1_sign() and ASN1_verify() functions. -These functions will put the correct algorithm identifiers in the correct -places in the structures. - -eric --- -Eric Young | BOOL is tri-state according to Bill Gates. -AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage(). - -==== x509 ======================================================= - -X509_verify() -X509_sign() - -X509_get_version() -X509_get_serialNumber() -X509_get_issuer() -X509_get_subject() -X509_get_notBefore() -X509_get_notAfter() -X509_get_pubkey() - -X509_set_version() -X509_set_serialNumber() -X509_set_issuer() -X509_set_subject() -X509_set_notBefore() -X509_set_notAfter() -X509_set_pubkey() - -X509_get_extensions() -X509_set_extensions() - -X509_EXTENSIONS_clear() -X509_EXTENSIONS_retrieve() -X509_EXTENSIONS_add() -X509_EXTENSIONS_delete() - -==== x509 attribute ================================================ - -PKCS7 - STACK of X509_ATTRIBUTES - ASN1_OBJECT - STACK of ASN1_TYPE - -So it is - -p7.xa[].obj -p7.xa[].data[] - -get_obj_by_nid(STACK , nid) -get_num_by_nid(STACK , nid) -get_data_by_nid(STACK , nid, index) - -X509_ATTRIBUTE *X509_ATTRIBUTE_new(void ); -void X509_ATTRIBUTE_free(X509_ATTRIBUTE *a); - -X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_NID(X509_ATTRIBUTE **ex, - int nid, STACK *value); - -X509_ATTRIBUTE *X509_ATTRIBUTE_create_by_OBJ(X509_ATTRIBUTE **ex, - int nid, STACK *value); - -int X509_ATTRIBUTE_set_object(X509_ATTRIBUTE *ex,ASN1_OBJECT *obj); -int X509_ATTRIBUTE_add_data(X509_ATTRIBUTE *ex, int index, - ASN1_TYPE *value); - -ASN1_OBJECT * X509_ATTRIBUTE_get_object(X509_ATTRIBUTE *ex); -int X509_ATTRIBUTE_get_num(X509_ATTRIBUTE *ne); -ASN1_TYPE * X509_ATTRIBUTE_get_data(X509_ATTRIBUTE *ne,int index); - -ASN1_TYPE * X509_ATTRIBUTE_get_data_by_NID(X509_ATTRIBUTE *ne, - ASN1_OBJECT *obj); - -X509_ATTRIBUTE *PKCS7_get_s_att_by_NID(PKCS7 *p7,int nid); -X509_ATTRIBUTE *PKCS7_get_u_att_by_NID(PKCS7 *p7,int nid); - -==== x509 v3 ======================================================== - -The 'new' system. - -The X509_EXTENSION_METHOD includes extensions and attributes and/or names. -Basically everthing that can be added to an X509 with an OID identifying it. - -It operates via 2 methods per object id. -int a2i_XXX(X509 *x,char *str,int len); -int i2a_XXX(BIO *bp,X509 *x); - -The a2i_XXX function will add the object with a value converted from the -string into the X509. Len can be -1 in which case the length is calculated -via strlen(str). Applications can always use direct knowledge to load and -unload the relevent objects themselves. - -i2a_XXX will print to the passed BIO, a text representation of the -relevet object. Use a memory BIO if you want it printed to a buffer :-). - -X509_add_by_NID(X509 *x,int nid,char *str,int len); -X509_add_by_OBJ(X509 *x,ASN1_OBJECT *obj,char *str,int len); - -X509_print_by_name(BIO *bp,X509 *x); -X509_print_by_NID(BIO *bp,X509 *x); -X509_print_by_OBJ(BIO *bp,X509 *x); - -==== verify ======================================================== - -X509_verify_cert_chain( - CERT_STORE *cert_store, - STACK /* X509 */ *certs, - int *verify_result, - int (*verify_error_callback)() - char *argument_to_callback, /* SSL */ - -app_verify_callback( - char *app_verify_arg, /* from SSL_CTX */ - STACK /* X509 */ *certs, - int *verify_result, - int (*verify_error_callback)() - SSL *s, - -int X509_verify_cert( - CERT_STORE *cert_store, - X509 *x509, - int *verify_result, - int (*verify_error_callback)(), - char *arg, - -==== apps.doc ======================================================== - -The applications - -Ok, where to begin.... -In the begining, when SSLeay was small (April 1995), there -were but few applications, they did happily cohabit in -the one bin directory. Then over time, they did multiply and grow, -and they started to look like microsoft software; 500k to print 'hello world'. -A new approach was needed. They were coalessed into one 'Monolithic' -application, ssleay. This one program is composed of many programs that -can all be compiled independantly. - -ssleay has 3 modes of operation. -1) If the ssleay binary has the name of one of its component programs, it -executes that program and then exits. This can be achieved by using hard or -symbolic links, or failing that, just renaming the binary. -2) If the first argument to ssleay is the name of one of the component -programs, that program runs that program and then exits. -3) If there are no arguments, ssleay enters a 'command' mode. Each line is -interpreted as a program name plus arguments. After each 'program' is run, -ssleay returns to the comand line. - -dgst - message digests -enc - encryption and base64 encoding - -ans1parse - 'pulls' appart ASN.1 encoded objects like certificates. - -dh - Diffle-Hellman parameter manipulation. -rsa - RSA manipulations. -crl - Certificate revokion list manipulations -x509 - X509 cert fiddles, including signing. -pkcs7 - pkcs7 manipulation, only DER versions right now. - -genrsa - generate an RSA private key. -gendh - Generate a set of Diffle-Hellman parameters. -req - Generate a PKCS#10 object, a certificate request. - -s_client - SSL client program -s_server - SSL server program -s_time - A SSL protocol timing program -s_mult - Another SSL server, but it multiplexes - connections. -s_filter - under development - -errstr - Convert SSLeay error numbers to strings. -ca - Sign certificate requests, and generate - certificate revokion lists -crl2pkcs7 - put a crl and certifcates into a pkcs7 object. -speed - Benchmark the ciphers. -verify - Check certificates -hashdir - under development - -[ there a now a few more options, play with the program to see what they - are ] - -==== asn1.doc ======================================================== - -The ASN.1 Routines. - -ASN.1 is a specification for how to encode structured 'data' in binary form. -The approach I have take to the manipulation of structures and their encoding -into ASN.1 is as follows. - -For each distinct structure there are 4 function of the following form -TYPE *TYPE_new(void); -void TYPE_free(TYPE *); -TYPE *d2i_TYPE(TYPE **a,unsigned char **pp,long length); -long i2d_TYPE(TYPE *a,unsigned char **pp); /* CHECK RETURN VALUE */ - -where TYPE is the type of the 'object'. The TYPE that have these functions -can be in one of 2 forms, either the internal C malloc()ed data structure -or in the DER (a variant of ASN.1 encoding) binary encoding which is just -an array of unsigned bytes. The 'i2d' functions converts from the internal -form to the DER form and the 'd2i' functions convert from the DER form to -the internal form. - -The 'new' function returns a malloc()ed version of the structure with all -substructures either created or left as NULL pointers. For 'optional' -fields, they are normally left as NULL to indicate no value. For variable -size sub structures (often 'SET OF' or 'SEQUENCE OF' in ASN.1 syntax) the -STACK data type is used to hold the values. Have a read of stack.doc -and have a look at the relevant header files to see what I mean. If there -is an error while malloc()ing the structure, NULL is returned. - -The 'free' function will free() all the sub components of a particular -structure. If any of those sub components have been 'removed', replace -them with NULL pointers, the 'free' functions are tolerant of NULL fields. - -The 'd2i' function copies a binary representation into a C structure. It -operates as follows. 'a' is a pointer to a pointer to -the structure to populate, 'pp' is a pointer to a pointer to where the DER -byte string is located and 'length' is the length of the '*pp' data. -If there are no errors, a pointer to the populated structure is returned. -If there is an error, NULL is returned. Errors can occur because of -malloc() failures but normally they will be due to syntax errors in the DER -encoded data being parsed. It is also an error if there was an -attempt to read more that 'length' bytes from '*p'. If -everything works correctly, the value in '*p' is updated -to point at the location just beyond where the DER -structure was read from. In this way, chained calls to 'd2i' type -functions can be made, with the pointer into the 'data' array being -'walked' along the input byte array. -Depending on the value passed for 'a', different things will be done. If -'a' is NULL, a new structure will be malloc()ed and returned. If '*a' is -NULL, a new structure will be malloc()ed and put into '*a' and returned. -If '*a' is not NULL, the structure in '*a' will be populated, or in the -case of an error, free()ed and then returned. -Having these semantics means that a structure -can call a 'd2i' function to populate a field and if the field is currently -NULL, the structure will be created. - -The 'i2d' function type is used to copy a C structure to a byte array. -The parameter 'a' is the structure to convert and '*p' is where to put it. -As for the 'd2i' type structure, 'p' is updated to point after the last -byte written. If p is NULL, no data is written. The function also returns -the number of bytes written. Where this becomes useful is that if the -function is called with a NULL 'p' value, the length is returned. This can -then be used to malloc() an array of bytes and then the same function can -be recalled passing the malloced array to be written to. e.g. - -int len; -unsigned char *bytes,*p; -len=i2d_X509(x,NULL); /* get the size of the ASN1 encoding of 'x' */ -if ((bytes=(unsigned char *)malloc(len)) == NULL) - goto err; -p=bytes; -i2d_X509(x,&p); - -Please note that a new variable, 'p' was passed to i2d_X509. After the -call to i2d_X509 p has been incremented by len bytes. - -Now the reason for this functional organisation is that it allows nested -structures to be built up by calling these functions as required. There -are various macros used to help write the general 'i2d', 'd2i', 'new' and -'free' functions. They are discussed in another file and would only be -used by some-one wanting to add new structures to the library. As you -might be able to guess, the process of writing ASN.1 files can be a bit CPU -expensive for complex structures. I'm willing to live with this since the -simpler library code make my life easier and hopefully most programs using -these routines will have their execution profiles dominated by cipher or -message digest routines. -What follows is a list of 'TYPE' values and the corresponding ASN.1 -structure and where it is used. - -TYPE ASN.1 -ASN1_INTEGER INTEGER -ASN1_BIT_STRING BIT STRING -ASN1_OCTET_STRING OCTET STRING -ASN1_OBJECT OBJECT IDENTIFIER -ASN1_PRINTABLESTRING PrintableString -ASN1_T61STRING T61String -ASN1_IA5STRING IA5String -ASN1_UTCTIME UTCTime -ASN1_TYPE Any of the above mentioned types plus SEQUENCE and SET - -Most of the above mentioned types are actualled stored in the -ASN1_BIT_STRING type and macros are used to differentiate between them. -The 3 types used are - -typedef struct asn1_object_st - { - /* both null if a dynamic ASN1_OBJECT, one is - * defined if a 'static' ASN1_OBJECT */ - char *sn,*ln; - int nid; - int length; - unsigned char *data; - } ASN1_OBJECT; -This is used to store ASN1 OBJECTS. Read 'objects.doc' for details ono -routines to manipulate this structure. 'sn' and 'ln' are used to hold text -strings that represent the object (short name and long or lower case name). -These are used by the 'OBJ' library. 'nid' is a number used by the OBJ -library to uniquely identify objects. The ASN1 routines will populate the -'length' and 'data' fields which will contain the bit string representing -the object. - -typedef struct asn1_bit_string_st - { - int length; - int type; - unsigned char *data; - } ASN1_BIT_STRING; -This structure is used to hold all the other base ASN1 types except for -ASN1_UTCTIME (which is really just a 'char *'). Length is the number of -bytes held in data and type is the ASN1 type of the object (there is a list -in asn1.h). - -typedef struct asn1_type_st - { - int type; - union { - char *ptr; - ASN1_INTEGER * integer; - ASN1_BIT_STRING * bit_string; - ASN1_OCTET_STRING * octet_string; - ASN1_OBJECT * object; - ASN1_PRINTABLESTRING * printablestring; - ASN1_T61STRING * t61string; - ASN1_IA5STRING * ia5string; - ASN1_UTCTIME * utctime; - ASN1_BIT_STRING * set; - ASN1_BIT_STRING * sequence; - } value; - } ASN1_TYPE; -This structure is used in a few places when 'any' type of object can be -expected. - -X509 Certificate -X509_CINF CertificateInfo -X509_ALGOR AlgorithmIdentifier -X509_NAME Name -X509_NAME_ENTRY A single sub component of the name. -X509_VAL Validity -X509_PUBKEY SubjectPublicKeyInfo -The above mentioned types are declared in x509.h. They are all quite -straight forward except for the X509_NAME/X509_NAME_ENTRY pair. -A X509_NAME is a STACK (see stack.doc) of X509_NAME_ENTRY's. -typedef struct X509_name_entry_st - { - ASN1_OBJECT *object; - ASN1_BIT_STRING *value; - int set; - int size; /* temp variable */ - } X509_NAME_ENTRY; -The size is a temporary variable used by i2d_NAME and set is the set number -for the particular NAME_ENTRY. A X509_NAME is encoded as a sequence of -sequence of sets. Normally each set contains only a single item. -Sometimes it contains more. Normally throughout this library there will be -only one item per set. The set field contains the 'set' that this entry is -a member of. So if you have just created a X509_NAME structure and -populated it with X509_NAME_ENTRYs, you should then traverse the X509_NAME -(which is just a STACK) and set the 'set/' field to incrementing numbers. -For more details on why this is done, read the ASN.1 spec for Distinguished -Names. - -X509_REQ CertificateRequest -X509_REQ_INFO CertificateRequestInfo -These are used to hold certificate requests. - -X509_CRL CertificateRevocationList -These are used to hold a certificate revocation list - -RSAPrivateKey PrivateKeyInfo -RSAPublicKey PublicKeyInfo -Both these 'function groups' operate on 'RSA' structures (see rsa.doc). -The difference is that the RSAPublicKey operations only manipulate the m -and e fields in the RSA structure. - -DSAPrivateKey DSS private key -DSAPublicKey DSS public key -Both these 'function groups' operate on 'DSS' structures (see dsa.doc). -The difference is that the RSAPublicKey operations only manipulate the -XXX fields in the DSA structure. - -DHparams DHParameter -This is used to hold the p and g value for The Diffie-Hellman operation. -The function deal with the 'DH' strucure (see dh.doc). - -Now all of these function types can be used with several other functions to give -quite useful set of general manipulation routines. Normally one would -not uses these functions directly but use them via macros. - -char *ASN1_dup(int (*i2d)(),char *(*d2i)(),char *x); -'x' is the input structure case to a 'char *', 'i2d' is the 'i2d_TYPE' -function for the type that 'x' is and d2i is the 'd2i_TYPE' function for the -type that 'x' is. As is obvious from the parameters, this function -duplicates the strucutre by transforming it into the DER form and then -re-loading it into a new strucutre and returning the new strucutre. This -is obviously a bit cpu intensive but when faced with a complex dynamic -structure this is the simplest programming approach. There are macros for -duplicating the major data types but is simple to add extras. - -char *ASN1_d2i_fp(char *(*new)(),char *(*d2i)(),FILE *fp,unsigned char **x); -'x' is a pointer to a pointer of the 'desired type'. new and d2i are the -corresponding 'TYPE_new' and 'd2i_TYPE' functions for the type and 'fp' is -an open file pointer to read from. This function reads from 'fp' as much -data as it can and then uses 'd2i' to parse the bytes to load and return -the parsed strucutre in 'x' (if it was non-NULL) and to actually return the -strucutre. The behavior of 'x' is as per all the other d2i functions. - -char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x); -The 'BIO' is the new IO type being used in SSLeay (see bio.doc). This -function is the same as ASN1_d2i_fp() except for the BIO argument. -ASN1_d2i_fp() actually calls this function. - -int ASN1_i2d_fp(int (*i2d)(),FILE *out,unsigned char *x); -'x' is converted to bytes by 'i2d' and then written to 'out'. ASN1_i2d_fp -and ASN1_d2i_fp are not really symetric since ASN1_i2d_fp will read all -available data from the file pointer before parsing a single item while -ASN1_i2d_fp can be used to write a sequence of data objects. To read a -series of objects from a file I would sugest loading the file into a buffer -and calling the relevent 'd2i' functions. - -char *ASN1_d2i_bio(char *(*new)(),char *(*d2i)(),BIO *fp,unsigned char **x); -This function is the same as ASN1_i2d_fp() except for the BIO argument. -ASN1_i2d_fp() actually calls this function. - -char * PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)()); -This function will read the next PEM encoded (base64) object of the same -type as 'x' (loaded by the d2i function). 'name' is the name that is in -the '-----BEGIN name-----' that designates the start of that object type. -If the data is encrypted, 'cb' will be called to prompt for a password. If -it is NULL a default function will be used to prompt from the password. -'x' is delt with as per the standard 'd2i' function interface. This -function can be used to read a series of objects from a file. While any -data type can be encrypted (see PEM_ASN1_write) only RSA private keys tend -to be encrypted. - -char * PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *fp, - char **x,int (*cb)()); -Same as PEM_ASN1_read() except using a BIO. This is called by -PEM_ASN1_read(). - -int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x,EVP_CIPHER *enc, - unsigned char *kstr,int klen,int (*callback)()); - -int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *fp, - char *x,EVP_CIPHER *enc,unsigned char *kstr,int klen, - int (*callback)()); - -int ASN1_sign(int (*i2d)(), X509_ALGOR *algor1, X509_ALGOR *algor2, - ASN1_BIT_STRING *signature, char *data, RSA *rsa, EVP_MD *type); -int ASN1_verify(int (*i2d)(), X509_ALGOR *algor1, - ASN1_BIT_STRING *signature,char *data, RSA *rsa); - -int ASN1_BIT_STRING_cmp(ASN1_BIT_STRING *a, ASN1_BIT_STRING *b); -ASN1_BIT_STRING *ASN1_BIT_STRING_type_new(int type ); - -int ASN1_UTCTIME_check(ASN1_UTCTIME *a); -void ASN1_UTCTIME_print(BIO *fp,ASN1_UTCTIME *a); -ASN1_UTCTIME *ASN1_UTCTIME_dup(ASN1_UTCTIME *a); - -ASN1_BIT_STRING *d2i_asn1_print_type(ASN1_BIT_STRING **a,unsigned char **pp, - long length,int type); - -int i2d_ASN1_SET(STACK *a, unsigned char **pp, - int (*func)(), int ex_tag, int ex_class); -STACK * d2i_ASN1_SET(STACK **a, unsigned char **pp, long length, - char *(*func)(), int ex_tag, int ex_class); - -int i2a_ASN1_OBJECT(BIO *bp,ASN1_OBJECT *object); -int i2a_ASN1_INTEGER(BIO *bp, ASN1_INTEGER *a); -int a2i_ASN1_INTEGER(BIO *bp,ASN1_INTEGER *bs,char *buf,int size); - -int ASN1_INTEGER_set(ASN1_INTEGER *a, long v); -long ASN1_INTEGER_get(ASN1_INTEGER *a); -ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai); -BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn); - -/* given a string, return the correct type. Max is the maximum number - * of bytes to parse. It stops parsing when 'max' bytes have been - * processed or a '\0' is hit */ -int ASN1_PRINTABLE_type(unsigned char *s,int max); - -void ASN1_parse(BIO *fp,unsigned char *pp,long len); - -int i2d_ASN1_bytes(ASN1_BIT_STRING *a, unsigned char **pp, int tag, int class); -ASN1_BIT_STRING *d2i_ASN1_bytes(ASN1_OCTET_STRING **a, unsigned char **pp, - long length, int Ptag, int Pclass); - -/* PARSING */ -int asn1_Finish(ASN1_CTX *c); - -/* SPECIALS */ -int ASN1_get_object(unsigned char **pp, long *plength, int *ptag, - int *pclass, long omax); -int ASN1_check_infinite_end(unsigned char **p,long len); -void ASN1_put_object(unsigned char **pp, int constructed, int length, - int tag, int class); -int ASN1_object_size(int constructed, int length, int tag); - -X509 * X509_get_cert(CERTIFICATE_CTX *ctx,X509_NAME * name,X509 *tmp_x509); -int X509_add_cert(CERTIFICATE_CTX *ctx,X509 *); - -char * X509_cert_verify_error_string(int n); -int X509_add_cert_file(CERTIFICATE_CTX *c,char *file, int type); -char * X509_gmtime (char *s, long adj); -int X509_add_cert_dir (CERTIFICATE_CTX *c,char *dir, int type); -int X509_load_verify_locations (CERTIFICATE_CTX *ctx, - char *file_env, char *dir_env); -int X509_set_default_verify_paths(CERTIFICATE_CTX *cts); -X509 * X509_new_D2i_X509(int len, unsigned char *p); -char * X509_get_default_cert_area(void ); -char * X509_get_default_cert_dir(void ); -char * X509_get_default_cert_file(void ); -char * X509_get_default_cert_dir_env(void ); -char * X509_get_default_cert_file_env(void ); -char * X509_get_default_private_dir(void ); -X509_REQ *X509_X509_TO_req(X509 *x, RSA *rsa); -int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)()); - -CERTIFICATE_CTX *CERTIFICATE_CTX_new(); -void CERTIFICATE_CTX_free(CERTIFICATE_CTX *c); - -void X509_NAME_print(BIO *fp, X509_NAME *name, int obase); -int X509_print_fp(FILE *fp,X509 *x); -int X509_print(BIO *fp,X509 *x); - -X509_INFO * X509_INFO_new(void); -void X509_INFO_free(X509_INFO *a); - -char * X509_NAME_oneline(X509_NAME *a); - -#define X509_verify(x,rsa) -#define X509_REQ_verify(x,rsa) -#define X509_CRL_verify(x,rsa) - -#define X509_sign(x,rsa,md) -#define X509_REQ_sign(x,rsa,md) -#define X509_CRL_sign(x,rsa,md) - -#define X509_dup(x509) -#define d2i_X509_fp(fp,x509) -#define i2d_X509_fp(fp,x509) -#define d2i_X509_bio(bp,x509) -#define i2d_X509_bio(bp,x509) - -#define X509_CRL_dup(crl) -#define d2i_X509_CRL_fp(fp,crl) -#define i2d_X509_CRL_fp(fp,crl) -#define d2i_X509_CRL_bio(bp,crl) -#define i2d_X509_CRL_bio(bp,crl) - -#define X509_REQ_dup(req) -#define d2i_X509_REQ_fp(fp,req) -#define i2d_X509_REQ_fp(fp,req) -#define d2i_X509_REQ_bio(bp,req) -#define i2d_X509_REQ_bio(bp,req) - -#define RSAPrivateKey_dup(rsa) -#define d2i_RSAPrivateKey_fp(fp,rsa) -#define i2d_RSAPrivateKey_fp(fp,rsa) -#define d2i_RSAPrivateKey_bio(bp,rsa) -#define i2d_RSAPrivateKey_bio(bp,rsa) - -#define X509_NAME_dup(xn) -#define X509_NAME_ENTRY_dup(ne) - -void X509_REQ_print_fp(FILE *fp,X509_REQ *req); -void X509_REQ_print(BIO *fp,X509_REQ *req); - -RSA *X509_REQ_extract_key(X509_REQ *req); -RSA *X509_extract_key(X509 *x509); - -int X509_issuer_and_serial_cmp(X509 *a, X509 *b); -unsigned long X509_issuer_and_serial_hash(X509 *a); - -X509_NAME * X509_get_issuer_name(X509 *a); -int X509_issuer_name_cmp(X509 *a, X509 *b); -unsigned long X509_issuer_name_hash(X509 *a); - -X509_NAME * X509_get_subject_name(X509 *a); -int X509_subject_name_cmp(X509 *a,X509 *b); -unsigned long X509_subject_name_hash(X509 *x); - -int X509_NAME_cmp (X509_NAME *a, X509_NAME *b); -unsigned long X509_NAME_hash(X509_NAME *x); - - -==== bio.doc ======================================================== - -BIO Routines - -This documentation is rather sparse, you are probably best -off looking at the code for specific details. - -The BIO library is a IO abstraction that was originally -inspired by the need to have callbacks to perform IO to FILE -pointers when using Windows 3.1 DLLs. There are two types -of BIO; a source/sink type and a filter type. -The source/sink methods are as follows: -- BIO_s_mem() memory buffer - a read/write byte array that - grows until memory runs out :-). -- BIO_s_file() FILE pointer - A wrapper around the normal - 'FILE *' commands, good for use with stdin/stdout. -- BIO_s_fd() File descriptor - A wrapper around file - descriptors, often used with pipes. -- BIO_s_socket() Socket - Used around sockets. It is - mostly in the Microsoft world that sockets are different - from file descriptors and there are all those ugly winsock - commands. -- BIO_s_null() Null - read nothing and write nothing.; a - useful endpoint for filter type BIO's specifically things - like the message digest BIO. - -The filter types are -- BIO_f_buffer() IO buffering - does output buffering into - larger chunks and performs input buffering to allow gets() - type functions. -- BIO_f_md() Message digest - a transparent filter that can - be asked to return a message digest for the data that has - passed through it. -- BIO_f_cipher() Encrypt or decrypt all data passing - through the filter. -- BIO_f_base64() Base64 decode on read and encode on write. -- BIO_f_ssl() A filter that performs SSL encryption on the - data sent through it. - -Base BIO functions. -The BIO library has a set of base functions that are -implemented for each particular type. Filter BIOs will -normally call the equivalent function on the source/sink BIO -that they are layered on top of after they have performed -some modification to the data stream. Multiple filter BIOs -can be 'push' into a stack of modifers, so to read from a -file, unbase64 it, then decrypt it, a BIO_f_cipher, -BIO_f_base64 and a BIO_s_file would probably be used. If a -sha-1 and md5 message digest needed to be generated, a stack -two BIO_f_md() BIOs and a BIO_s_null() BIO could be used. -The base functions are -- BIO *BIO_new(BIO_METHOD *type); Create a new BIO of type 'type'. -- int BIO_free(BIO *a); Free a BIO structure. Depending on - the configuration, this will free the underlying data - object for a source/sink BIO. -- int BIO_read(BIO *b, char *data, int len); Read upto 'len' - bytes into 'data'. -- int BIO_gets(BIO *bp,char *buf, int size); Depending on - the BIO, this can either be a 'get special' or a get one - line of data, as per fgets(); -- int BIO_write(BIO *b, char *data, int len); Write 'len' - bytes from 'data' to the 'b' BIO. -- int BIO_puts(BIO *bp,char *buf); Either a 'put special' or - a write null terminated string as per fputs(). -- long BIO_ctrl(BIO *bp,int cmd,long larg,char *parg); A - control function which is used to manipulate the BIO - structure and modify it's state and or report on it. This - function is just about never used directly, rather it - should be used in conjunction with BIO_METHOD specific - macros. -- BIO *BIO_push(BIO *new_top, BIO *old); new_top is apped to the - top of the 'old' BIO list. new_top should be a filter BIO. - All writes will go through 'new_top' first and last on read. - 'old' is returned. -- BIO *BIO_pop(BIO *bio); the new topmost BIO is returned, NULL if - there are no more. - -If a particular low level BIO method is not supported -(normally BIO_gets()), -2 will be returned if that method is -called. Otherwise the IO methods (read, write, gets, puts) -will return the number of bytes read or written, and 0 or -1 -for error (or end of input). For the -1 case, -BIO_should_retry(bio) can be called to determine if it was a -genuine error or a temporary problem. -2 will also be -returned if the BIO has not been initalised yet, in all -cases, the correct error codes are set (accessible via the -ERR library). - - -The following functions are convenience functions: -- int BIO_printf(BIO *bio, char * format, ..); printf but - to a BIO handle. -- long BIO_ctrl_int(BIO *bp,int cmd,long larg,int iarg); a - convenience function to allow a different argument types - to be passed to BIO_ctrl(). -- int BIO_dump(BIO *b,char *bytes,int len); output 'len' - bytes from 'bytes' in a hex dump debug format. -- long BIO_debug_callback(BIO *bio, int cmd, char *argp, int - argi, long argl, long ret) - a default debug BIO callback, - this is mentioned below. To use this one normally has to - use the BIO_set_callback_arg() function to assign an - output BIO for the callback to use. -- BIO *BIO_find_type(BIO *bio,int type); when there is a 'stack' - of BIOs, this function scan the list and returns the first - that is of type 'type', as listed in buffer.h under BIO_TYPE_XXX. -- void BIO_free_all(BIO *bio); Free the bio and all other BIOs - in the list. It walks the bio->next_bio list. - - - -Extra commands are normally implemented as macros calling BIO_ctrl(). -- BIO_number_read(BIO *bio) - the number of bytes processed - by BIO_read(bio,.). -- BIO_number_written(BIO *bio) - the number of bytes written - by BIO_write(bio,.). -- BIO_reset(BIO *bio) - 'reset' the BIO. -- BIO_eof(BIO *bio) - non zero if we are at the current end - of input. -- BIO_set_close(BIO *bio, int close_flag) - set the close flag. -- BIO_get_close(BIO *bio) - return the close flag. - BIO_pending(BIO *bio) - return the number of bytes waiting - to be read (normally buffered internally). -- BIO_flush(BIO *bio) - output any data waiting to be output. -- BIO_should_retry(BIO *io) - after a BIO_read/BIO_write - operation returns 0 or -1, a call to this function will - return non zero if you should retry the call later (this - is for non-blocking IO). -- BIO_should_read(BIO *io) - we should retry when data can - be read. -- BIO_should_write(BIO *io) - we should retry when data can - be written. -- BIO_method_name(BIO *io) - return a string for the method name. -- BIO_method_type(BIO *io) - return the unique ID of the BIO method. -- BIO_set_callback(BIO *io, long (*callback)(BIO *io, int - cmd, char *argp, int argi, long argl, long ret); - sets - the debug callback. -- BIO_get_callback(BIO *io) - return the assigned function - as mentioned above. -- BIO_set_callback_arg(BIO *io, char *arg) - assign some - data against the BIO. This is normally used by the debug - callback but could in reality be used for anything. To - get an idea of how all this works, have a look at the code - in the default debug callback mentioned above. The - callback can modify the return values. - -Details of the BIO_METHOD structure. -typedef struct bio_method_st - { - int type; - char *name; - int (*bwrite)(); - int (*bread)(); - int (*bputs)(); - int (*bgets)(); - long (*ctrl)(); - int (*create)(); - int (*destroy)(); - } BIO_METHOD; - -The 'type' is the numeric type of the BIO, these are listed in buffer.h; -'Name' is a textual representation of the BIO 'type'. -The 7 function pointers point to the respective function -methods, some of which can be NULL if not implemented. -The BIO structure -typedef struct bio_st - { - BIO_METHOD *method; - long (*callback)(BIO * bio, int mode, char *argp, int - argi, long argl, long ret); - char *cb_arg; /* first argument for the callback */ - int init; - int shutdown; - int flags; /* extra storage */ - int num; - char *ptr; - struct bio_st *next_bio; /* used by filter BIOs */ - int references; - unsigned long num_read; - unsigned long num_write; - } BIO; - -- 'Method' is the BIO method. -- 'callback', when configured, is called before and after - each BIO method is called for that particular BIO. This - is intended primarily for debugging and of informational feedback. -- 'init' is 0 when the BIO can be used for operation. - Often, after a BIO is created, a number of operations may - need to be performed before it is available for use. An - example is for BIO_s_sock(). A socket needs to be - assigned to the BIO before it can be used. -- 'shutdown', this flag indicates if the underlying - communication primitive being used should be closed/freed - when the BIO is closed. -- 'flags' is used to hold extra state. It is primarily used - to hold information about why a non-blocking operation - failed and to record startup protocol information for the - SSL BIO. -- 'num' and 'ptr' are used to hold instance specific state - like file descriptors or local data structures. -- 'next_bio' is used by filter BIOs to hold the pointer of the - next BIO in the chain. written data is sent to this BIO and - data read is taken from it. -- 'references' is used to indicate the number of pointers to - this structure. This needs to be '1' before a call to - BIO_free() is made if the BIO_free() function is to - actually free() the structure, otherwise the reference - count is just decreased. The actual BIO subsystem does - not really use this functionality but it is useful when - used in more advanced applicaion. -- num_read and num_write are the total number of bytes - read/written via the 'read()' and 'write()' methods. - -BIO_ctrl operations. -The following is the list of standard commands passed as the -second parameter to BIO_ctrl() and should be supported by -all BIO as best as possible. Some are optional, some are -manditory, in any case, where is makes sense, a filter BIO -should pass such requests to underlying BIO's. -- BIO_CTRL_RESET - Reset the BIO back to an initial state. -- BIO_CTRL_EOF - return 0 if we are not at the end of input, - non 0 if we are. -- BIO_CTRL_INFO - BIO specific special command, normal - information return. -- BIO_CTRL_SET - set IO specific parameter. -- BIO_CTRL_GET - get IO specific parameter. -- BIO_CTRL_GET_CLOSE - Get the close on BIO_free() flag, one - of BIO_CLOSE or BIO_NOCLOSE. -- BIO_CTRL_SET_CLOSE - Set the close on BIO_free() flag. -- BIO_CTRL_PENDING - Return the number of bytes available - for instant reading -- BIO_CTRL_FLUSH - Output pending data, return number of bytes output. -- BIO_CTRL_SHOULD_RETRY - After an IO error (-1 returned) - should we 'retry' when IO is possible on the underlying IO object. -- BIO_CTRL_RETRY_TYPE - What kind of IO are we waiting on. - -The following command is a special BIO_s_file() specific option. -- BIO_CTRL_SET_FILENAME - specify a file to open for IO. - -The BIO_CTRL_RETRY_TYPE needs a little more explanation. -When performing non-blocking IO, or say reading on a memory -BIO, when no data is present (or cannot be written), -BIO_read() and/or BIO_write() will return -1. -BIO_should_retry(bio) will return true if this is due to an -IO condition rather than an actual error. In the case of -BIO_s_mem(), a read when there is no data will return -1 and -a should retry when there is more 'read' data. -The retry type is deduced from 2 macros -BIO_should_read(bio) and BIO_should_write(bio). -Now while it may appear obvious that a BIO_read() failure -should indicate that a retry should be performed when more -read data is available, this is often not true when using -things like an SSL BIO. During the SSL protocol startup -multiple reads and writes are performed, triggered by any -SSL_read or SSL_write. -So to write code that will transparently handle either a -socket or SSL BIO, - i=BIO_read(bio,..) - if (I == -1) - { - if (BIO_should_retry(bio)) - { - if (BIO_should_read(bio)) - { - /* call us again when BIO can be read */ - } - if (BIO_should_write(bio)) - { - /* call us again when BIO can be written */ - } - } - } - -At this point in time only read and write conditions can be -used but in the future I can see the situation for other -conditions, specifically with SSL there could be a condition -of a X509 certificate lookup taking place and so the non- -blocking BIO_read would require a retry when the certificate -lookup subsystem has finished it's lookup. This is all -makes more sense and is easy to use in a event loop type -setup. -When using the SSL BIO, either SSL_read() or SSL_write()s -can be called during the protocol startup and things will -still work correctly. -The nice aspect of the use of the BIO_should_retry() macro -is that all the errno codes that indicate a non-fatal error -are encapsulated in one place. The Windows specific error -codes and WSAGetLastError() calls are also hidden from the -application. - -Notes on each BIO method. -Normally buffer.h is just required but depending on the -BIO_METHOD, ssl.h or evp.h will also be required. - -BIO_METHOD *BIO_s_mem(void); -- BIO_set_mem_buf(BIO *bio, BUF_MEM *bm, int close_flag) - - set the underlying BUF_MEM structure for the BIO to use. -- BIO_get_mem_ptr(BIO *bio, char **pp) - if pp is not NULL, - set it to point to the memory array and return the number - of bytes available. -A read/write BIO. Any data written is appended to the -memory array and any read is read from the front. This BIO -can be used for read/write at the same time. BIO_gets() is -supported in the fgets() sense. -BIO_CTRL_INFO can be used to retrieve pointers to the memory -buffer and it's length. - -BIO_METHOD *BIO_s_file(void); -- BIO_set_fp(BIO *bio, FILE *fp, int close_flag) - set 'FILE *' to use. -- BIO_get_fp(BIO *bio, FILE **fp) - get the 'FILE *' in use. -- BIO_read_filename(BIO *bio, char *name) - read from file. -- BIO_write_filename(BIO *bio, char *name) - write to file. -- BIO_append_filename(BIO *bio, char *name) - append to file. -This BIO sits over the normal system fread()/fgets() type -functions. Gets() is supported. This BIO in theory could be -used for read and write but it is best to think of each BIO -of this type as either a read or a write BIO, not both. - -BIO_METHOD *BIO_s_socket(void); -BIO_METHOD *BIO_s_fd(void); -- BIO_sock_should_retry(int i) - the underlying function - used to determine if a call should be retried; the - argument is the '0' or '-1' returned by the previous BIO - operation. -- BIO_fd_should_retry(int i) - same as the -- BIO_sock_should_retry() except that it is different internally. -- BIO_set_fd(BIO *bio, int fd, int close_flag) - set the - file descriptor to use -- BIO_get_fd(BIO *bio, int *fd) - get the file descriptor. -These two methods are very similar. Gets() is not -supported, if you want this functionality, put a -BIO_f_buffer() onto it. This BIO is bi-directional if the -underlying file descriptor is. This is normally the case -for sockets but not the case for stdio descriptors. - -BIO_METHOD *BIO_s_null(void); -Read and write as much data as you like, it all disappears -into this BIO. - -BIO_METHOD *BIO_f_buffer(void); -- BIO_get_buffer_num_lines(BIO *bio) - return the number of - complete lines in the buffer. -- BIO_set_buffer_size(BIO *bio, long size) - set the size of - the buffers. -This type performs input and output buffering. It performs -both at the same time. The size of the buffer can be set -via the set buffer size option. Data buffered for output is -only written when the buffer fills. - -BIO_METHOD *BIO_f_ssl(void); -- BIO_set_ssl(BIO *bio, SSL *ssl, int close_flag) - the SSL - structure to use. -- BIO_get_ssl(BIO *bio, SSL **ssl) - get the SSL structure - in use. -The SSL bio is a little different from normal BIOs because -the underlying SSL structure is a little different. A SSL -structure performs IO via a read and write BIO. These can -be different and are normally set via the -SSL_set_rbio()/SSL_set_wbio() calls. The SSL_set_fd() calls -are just wrappers that create socket BIOs and then call -SSL_set_bio() where the read and write BIOs are the same. -The BIO_push() operation makes the SSLs IO BIOs the same, so -make sure the BIO pushed is capable of two directional -traffic. If it is not, you will have to install the BIOs -via the more conventional SSL_set_bio() call. BIO_pop() will retrieve -the 'SSL read' BIO. - -BIO_METHOD *BIO_f_md(void); -- BIO_set_md(BIO *bio, EVP_MD *md) - set the message digest - to use. -- BIO_get_md(BIO *bio, EVP_MD **mdp) - return the digest - method in use in mdp, return 0 if not set yet. -- BIO_reset() reinitializes the digest (EVP_DigestInit()) - and passes the reset to the underlying BIOs. -All data read or written via BIO_read() or BIO_write() to -this BIO will be added to the calculated digest. This -implies that this BIO is only one directional. If read and -write operations are performed, two separate BIO_f_md() BIOs -are reuqired to generate digests on both the input and the -output. BIO_gets(BIO *bio, char *md, int size) will place the -generated digest into 'md' and return the number of bytes. -The EVP_MAX_MD_SIZE should probably be used to size the 'md' -array. Reading the digest will also reset it. - -BIO_METHOD *BIO_f_cipher(void); -- BIO_reset() reinitializes the cipher. -- BIO_flush() should be called when the last bytes have been - output to flush the final block of block ciphers. -- BIO_get_cipher_status(BIO *b), when called after the last - read from a cipher BIO, returns non-zero if the data - decrypted correctly, otherwise, 0. -- BIO_set_cipher(BIO *b, EVP_CIPHER *c, unsigned char *key, - unsigned char *iv, int encrypt) This function is used to - setup a cipher BIO. The length of key and iv are - specified by the choice of EVP_CIPHER. Encrypt is 1 to - encrypt and 0 to decrypt. - -BIO_METHOD *BIO_f_base64(void); -- BIO_flush() should be called when the last bytes have been output. -This BIO base64 encodes when writing and base64 decodes when -reading. It will scan the input until a suitable begin line -is found. After reading data, BIO_reset() will reset the -BIO to start scanning again. Do not mix reading and writing -on the same base64 BIO. It is meant as a single stream BIO. - -Directions type -both BIO_s_mem() -one/both BIO_s_file() -both BIO_s_fd() -both BIO_s_socket() -both BIO_s_null() -both BIO_f_buffer() -one BIO_f_md() -one BIO_f_cipher() -one BIO_f_base64() -both BIO_f_ssl() - -It is easy to mix one and two directional BIOs, all one has -to do is to keep two separate BIO pointers for reading and -writing and be careful about usage of underlying BIOs. The -SSL bio by it's very nature has to be two directional but -the BIO_push() command will push the one BIO into the SSL -BIO for both reading and writing. - -The best example program to look at is apps/enc.c and/or perhaps apps/dgst.c. - - -==== blowfish.doc ======================================================== - -The Blowfish library. - -Blowfish is a block cipher that operates on 64bit (8 byte) quantities. It -uses variable size key, but 128bit (16 byte) key would normally be considered -good. It can be used in all the modes that DES can be used. This -library implements the ecb, cbc, cfb64, ofb64 modes. - -Blowfish is quite a bit faster that DES, and much faster than IDEA or -RC2. It is one of the faster block ciphers. - -For all calls that have an 'input' and 'output' variables, they can be the -same. - -This library requires the inclusion of 'blowfish.h'. - -All of the encryption functions take what is called an BF_KEY as an -argument. An BF_KEY is an expanded form of the Blowfish key. -For all modes of the Blowfish algorithm, the BF_KEY used for -decryption is the same one that was used for encryption. - -The define BF_ENCRYPT is passed to specify encryption for the functions -that require an encryption/decryption flag. BF_DECRYPT is passed to -specify decryption. - -Please note that any of the encryption modes specified in my DES library -could be used with Blowfish. I have only implemented ecb, cbc, cfb64 and -ofb64 for the following reasons. -- ecb is the basic Blowfish encryption. -- cbc is the normal 'chaining' form for block ciphers. -- cfb64 can be used to encrypt single characters, therefore input and output - do not need to be a multiple of 8. -- ofb64 is similar to cfb64 but is more like a stream cipher, not as - secure (not cipher feedback) but it does not have an encrypt/decrypt mode. -- If you want triple Blowfish, thats 384 bits of key and you must be totally - obsessed with security. Still, if you want it, it is simple enough to - copy the function from the DES library and change the des_encrypt to - BF_encrypt; an exercise left for the paranoid reader :-). - -The functions are as follows: - -void BF_set_key( -BF_KEY *ks; -int len; -unsigned char *key; - BF_set_key converts an 'len' byte key into a BF_KEY. - A 'ks' is an expanded form of the 'key' which is used to - perform actual encryption. It can be regenerated from the Blowfish key - so it only needs to be kept when encryption or decryption is about - to occur. Don't save or pass around BF_KEY's since they - are CPU architecture dependent, 'key's are not. Blowfish is an - interesting cipher in that it can be used with a variable length - key. 'len' is the length of 'key' to be used as the key. - A 'len' of 16 is recomended by me, but blowfish can use upto - 72 bytes. As a warning, blowfish has a very very slow set_key - function, it actually runs BF_encrypt 521 times. - -void BF_encrypt(unsigned long *data, BF_KEY *key); -void BF_decrypt(unsigned long *data, BF_KEY *key); - These are the Blowfish encryption function that gets called by just - about every other Blowfish routine in the library. You should not - use this function except to implement 'modes' of Blowfish. - I say this because the - functions that call this routine do the conversion from 'char *' to - long, and this needs to be done to make sure 'non-aligned' memory - access do not occur. - Data is a pointer to 2 unsigned long's and key is the - BF_KEY to use. - -void BF_ecb_encrypt( -unsigned char *in, -unsigned char *out, -BF_KEY *key, -int encrypt); - This is the basic Electronic Code Book form of Blowfish (in DES this - mode is called Electronic Code Book so I'm going to use the term - for blowfish as well. - Input is encrypted into output using the key represented by - key. Depending on the encrypt, encryption or - decryption occurs. Input is 8 bytes long and output is 8 bytes. - -void BF_cbc_encrypt( -unsigned char *in, -unsigned char *out, -long length, -BF_KEY *ks, -unsigned char *ivec, -int encrypt); - This routine implements Blowfish in Cipher Block Chaining mode. - Input, which should be a multiple of 8 bytes is encrypted - (or decrypted) to output which will also be a multiple of 8 bytes. - The number of bytes is in length (and from what I've said above, - should be a multiple of 8). If length is not a multiple of 8, bad - things will probably happen. ivec is the initialisation vector. - This function updates iv after each call so that it can be passed to - the next call to BF_cbc_encrypt(). - -void BF_cfb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -BF_KEY *schedule, -unsigned char *ivec, -int *num, -int encrypt); - This is one of the more useful functions in this Blowfish library, it - implements CFB mode of Blowfish with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - 'Encrypt' is used to indicate encryption or decryption. - CFB64 mode operates by using the cipher to generate a stream - of bytes which is used to encrypt the plain text. - The cipher text is then encrypted to generate the next 64 bits to - be xored (incrementally) with the next 64 bits of plain - text. As can be seen from this, to encrypt or decrypt, - the same 'cipher stream' needs to be generated but the way the next - block of data is gathered for encryption is different for - encryption and decryption. - -void BF_ofb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -BF_KEY *schedule, -unsigned char *ivec, -int *num); - This functions implements OFB mode of Blowfish with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - This is in effect a stream cipher, there is no encryption or - decryption mode. - -For reading passwords, I suggest using des_read_pw_string() from my DES library. -To generate a password from a text string, I suggest using MD5 (or MD2) to -produce a 16 byte message digest that can then be passed directly to -BF_set_key(). - -===== -For more information about the specific Blowfish modes in this library -(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the -documentation on my DES library. What is said about DES is directly -applicable for Blowfish. - - -==== bn.doc ======================================================== - -The Big Number library. - -#include "bn.h" when using this library. - -This big number library was written for use in implementing the RSA and DH -public key encryption algorithms. As such, features such as negative -numbers have not been extensively tested but they should work as expected. -This library uses dynamic memory allocation for storing its data structures -and so there are no limit on the size of the numbers manipulated by these -routines but there is always the requirement to check return codes from -functions just in case a memory allocation error has occurred. - -The basic object in this library is a BIGNUM. It is used to hold a single -large integer. This type should be considered opaque and fields should not -be modified or accessed directly. -typedef struct bignum_st - { - int top; /* Index of last used d. */ - BN_ULONG *d; /* Pointer to an array of 'BITS2' bit chunks. */ - int max; /* Size of the d array. */ - int neg; - } BIGNUM; -The big number is stored in a malloced array of BN_ULONG's. A BN_ULONG can -be either 16, 32 or 64 bits in size, depending on the 'number of bits' -specified in bn.h. -The 'd' field is this array. 'max' is the size of the 'd' array that has -been allocated. 'top' is the 'last' entry being used, so for a value of 4, -bn.d[0]=4 and bn.top=1. 'neg' is 1 if the number is negative. -When a BIGNUM is '0', the 'd' field can be NULL and top == 0. - -Various routines in this library require the use of 'temporary' BIGNUM -variables during their execution. Due to the use of dynamic memory -allocation to create BIGNUMs being rather expensive when used in -conjunction with repeated subroutine calls, the BN_CTX structure is -used. This structure contains BN_CTX BIGNUMs. BN_CTX -is the maximum number of temporary BIGNUMs any publicly exported -function will use. - -#define BN_CTX 12 -typedef struct bignum_ctx - { - int tos; /* top of stack */ - BIGNUM *bn[BN_CTX]; /* The variables */ - } BN_CTX; - -The functions that follow have been grouped according to function. Most -arithmetic functions return a result in the first argument, sometimes this -first argument can also be an input parameter, sometimes it cannot. These -restrictions are documented. - -extern BIGNUM *BN_value_one; -There is one variable defined by this library, a BIGNUM which contains the -number 1. This variable is useful for use in comparisons and assignment. - -Get Size functions. - -int BN_num_bits(BIGNUM *a); - This function returns the size of 'a' in bits. - -int BN_num_bytes(BIGNUM *a); - This function (macro) returns the size of 'a' in bytes. - For conversion of BIGNUMs to byte streams, this is the number of - bytes the output string will occupy. If the output byte - format specifies that the 'top' bit indicates if the number is - signed, so an extra '0' byte is required if the top bit on a - positive number is being written, it is upto the application to - make this adjustment. Like I said at the start, I don't - really support negative numbers :-). - -Creation/Destruction routines. - -BIGNUM *BN_new(); - Return a new BIGNUM object. The number initially has a value of 0. If - there is an error, NULL is returned. - -void BN_free(BIGNUM *a); - Free()s a BIGNUM. - -void BN_clear(BIGNUM *a); - Sets 'a' to a value of 0 and also zeros all unused allocated - memory. This function is used to clear a variable of 'sensitive' - data that was held in it. - -void BN_clear_free(BIGNUM *a); - This function zeros the memory used by 'a' and then free()'s it. - This function should be used to BN_free() BIGNUMS that have held - sensitive numeric values like RSA private key values. Both this - function and BN_clear tend to only be used by RSA and DH routines. - -BN_CTX *BN_CTX_new(void); - Returns a new BN_CTX. NULL on error. - -void BN_CTX_free(BN_CTX *c); - Free a BN_CTX structure. The BIGNUMs in 'c' are BN_clear_free()ed. - -BIGNUM *bn_expand(BIGNUM *b, int bits); - This is an internal function that should not normally be used. It - ensures that 'b' has enough room for a 'bits' bit number. It is - mostly used by the various BIGNUM routines. If there is an error, - NULL is returned. if not, 'b' is returned. - -BIGNUM *BN_copy(BIGNUM *to, BIGNUM *from); - The 'from' is copied into 'to'. NULL is returned if there is an - error, otherwise 'to' is returned. - -BIGNUM *BN_dup(BIGNUM *a); - A new BIGNUM is created and returned containing the value of 'a'. - NULL is returned on error. - -Comparison and Test Functions. - -int BN_is_zero(BIGNUM *a) - Return 1 if 'a' is zero, else 0. - -int BN_is_one(a) - Return 1 is 'a' is one, else 0. - -int BN_is_word(a,w) - Return 1 if 'a' == w, else 0. 'w' is a BN_ULONG. - -int BN_cmp(BIGNUM *a, BIGNUM *b); - Return -1 if 'a' is less than 'b', 0 if 'a' and 'b' are the same - and 1 is 'a' is greater than 'b'. This is a signed comparison. - -int BN_ucmp(BIGNUM *a, BIGNUM *b); - This function is the same as BN_cmp except that the comparison - ignores the sign of the numbers. - -Arithmetic Functions -For all of these functions, 0 is returned if there is an error and 1 is -returned for success. The return value should always be checked. eg. -if (!BN_add(r,a,b)) goto err; -Unless explicitly mentioned, the 'return' value can be one of the -'parameters' to the function. - -int BN_add(BIGNUM *r, BIGNUM *a, BIGNUM *b); - Add 'a' and 'b' and return the result in 'r'. This is r=a+b. - -int BN_sub(BIGNUM *r, BIGNUM *a, BIGNUM *b); - Subtract 'a' from 'b' and put the result in 'r'. This is r=a-b. - -int BN_lshift(BIGNUM *r, BIGNUM *a, int n); - Shift 'a' left by 'n' bits. This is r=a*(2^n). - -int BN_lshift1(BIGNUM *r, BIGNUM *a); - Shift 'a' left by 1 bit. This form is more efficient than - BN_lshift(r,a,1). This is r=a*2. - -int BN_rshift(BIGNUM *r, BIGNUM *a, int n); - Shift 'a' right by 'n' bits. This is r=int(a/(2^n)). - -int BN_rshift1(BIGNUM *r, BIGNUM *a); - Shift 'a' right by 1 bit. This form is more efficient than - BN_rshift(r,a,1). This is r=int(a/2). - -int BN_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b); - Multiply a by b and return the result in 'r'. 'r' must not be - either 'a' or 'b'. It has to be a different BIGNUM. - This is r=a*b. - -int BN_sqr(BIGNUM *r, BIGNUM *a, BN_CTX *ctx); - Multiply a by a and return the result in 'r'. 'r' must not be - 'a'. This function is alot faster than BN_mul(r,a,a). This is r=a*a. - -int BN_div(BIGNUM *dv, BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx); - Divide 'm' by 'd' and return the result in 'dv' and the remainder - in 'rem'. Either of 'dv' or 'rem' can be NULL in which case that - value is not returned. 'ctx' needs to be passed as a source of - temporary BIGNUM variables. - This is dv=int(m/d), rem=m%d. - -int BN_mod(BIGNUM *rem, BIGNUM *m, BIGNUM *d, BN_CTX *ctx); - Find the remainder of 'm' divided by 'd' and return it in 'rem'. - 'ctx' holds the temporary BIGNUMs required by this function. - This function is more efficient than BN_div(NULL,rem,m,d,ctx); - This is rem=m%d. - -int BN_mod_mul(BIGNUM *r, BIGNUM *a, BIGNUM *b, BIGNUM *m,BN_CTX *ctx); - Multiply 'a' by 'b' and return the remainder when divided by 'm'. - 'ctx' holds the temporary BIGNUMs required by this function. - This is r=(a*b)%m. - -int BN_mod_exp(BIGNUM *r, BIGNUM *a, BIGNUM *p, BIGNUM *m,BN_CTX *ctx); - Raise 'a' to the 'p' power and return the remainder when divided by - 'm'. 'ctx' holds the temporary BIGNUMs required by this function. - This is r=(a^p)%m. - -int BN_reciprocal(BIGNUM *r, BIGNUM *m, BN_CTX *ctx); - Return the reciprocal of 'm'. 'ctx' holds the temporary variables - required. This function returns -1 on error, otherwise it returns - the number of bits 'r' is shifted left to make 'r' into an integer. - This number of bits shifted is required in BN_mod_mul_reciprocal(). - This is r=(1/m)<<(BN_num_bits(m)+1). - -int BN_mod_mul_reciprocal(BIGNUM *r, BIGNUM *x, BIGNUM *y, BIGNUM *m, - BIGNUM *i, int nb, BN_CTX *ctx); - This function is used to perform an efficient BN_mod_mul() - operation. If one is going to repeatedly perform BN_mod_mul() with - the same modulus is worth calculating the reciprocal of the modulus - and then using this function. This operation uses the fact that - a/b == a*r where r is the reciprocal of b. On modern computers - multiplication is very fast and big number division is very slow. - 'x' is multiplied by 'y' and then divided by 'm' and the remainder - is returned. 'i' is the reciprocal of 'm' and 'nb' is the number - of bits as returned from BN_reciprocal(). Normal usage is as follows. - bn=BN_reciprocal(i,m); - for (...) - { BN_mod_mul_reciprocal(r,x,y,m,i,bn,ctx); } - This is r=(x*y)%m. Internally it is approximately - r=(x*y)-m*(x*y/m) or r=(x*y)-m*((x*y*i) >> bn) - This function is used in BN_mod_exp() and BN_is_prime(). - -Assignment Operations - -int BN_one(BIGNUM *a) - Set 'a' to hold the value one. - This is a=1. - -int BN_zero(BIGNUM *a) - Set 'a' to hold the value zero. - This is a=0. - -int BN_set_word(BIGNUM *a, unsigned long w); - Set 'a' to hold the value of 'w'. 'w' is an unsigned long. - This is a=w. - -unsigned long BN_get_word(BIGNUM *a); - Returns 'a' in an unsigned long. Not remarkably, often 'a' will - be bigger than a word, in which case 0xffffffffL is returned. - -Word Operations -These functions are much more efficient that the normal bignum arithmetic -operations. - -BN_ULONG BN_mod_word(BIGNUM *a, unsigned long w); - Return the remainder of 'a' divided by 'w'. - This is return(a%w). - -int BN_add_word(BIGNUM *a, unsigned long w); - Add 'w' to 'a'. This function does not take the sign of 'a' into - account. This is a+=w; - -Bit operations. - -int BN_is_bit_set(BIGNUM *a, int n); - This function return 1 if bit 'n' is set in 'a' else 0. - -int BN_set_bit(BIGNUM *a, int n); - This function sets bit 'n' to 1 in 'a'. - This is a&= ~(1<<n); - -int BN_clear_bit(BIGNUM *a, int n); - This function sets bit 'n' to zero in 'a'. Return 0 if less - than 'n' bits in 'a' else 1. This is a&= ~(1<<n); - -int BN_mask_bits(BIGNUM *a, int n); - Truncate 'a' to n bits long. This is a&= ~((~0)<<n) - -Format conversion routines. - -BIGNUM *BN_bin2bn(unsigned char *s, int len,BIGNUM *ret); - This function converts 'len' bytes in 's' into a BIGNUM which - is put in 'ret'. If ret is NULL, a new BIGNUM is created. - Either this new BIGNUM or ret is returned. The number is - assumed to be in bigendian form in 's'. By this I mean that - to 'ret' is created as follows for 'len' == 5. - ret = s[0]*2^32 + s[1]*2^24 + s[2]*2^16 + s[3]*2^8 + s[4]; - This function cannot be used to convert negative numbers. It - is always assumed the number is positive. The application - needs to diddle the 'neg' field of th BIGNUM its self. - The better solution would be to save the numbers in ASN.1 format - since this is a defined standard for storing big numbers. - Look at the functions - - ASN1_INTEGER *BN_to_ASN1_INTEGER(BIGNUM *bn, ASN1_INTEGER *ai); - BIGNUM *ASN1_INTEGER_to_BN(ASN1_INTEGER *ai,BIGNUM *bn); - int i2d_ASN1_INTEGER(ASN1_INTEGER *a,unsigned char **pp); - ASN1_INTEGER *d2i_ASN1_INTEGER(ASN1_INTEGER **a,unsigned char **pp, - long length; - -int BN_bn2bin(BIGNUM *a, unsigned char *to); - This function converts 'a' to a byte string which is put into - 'to'. The representation is big-endian in that the most - significant byte of 'a' is put into to[0]. This function - returns the number of bytes used to hold 'a'. BN_num_bytes(a) - would return the same value and can be used to determine how - large 'to' needs to be. If the number is negative, this - information is lost. Since this library was written to - manipulate large positive integers, the inability to save and - restore them is not considered to be a problem by me :-). - As for BN_bin2bn(), look at the ASN.1 integer encoding funtions - for SSLeay. They use BN_bin2bn() and BN_bn2bin() internally. - -char *BN_bn2ascii(BIGNUM *a); - This function returns a malloc()ed string that contains the - ascii hexadecimal encoding of 'a'. The number is in bigendian - format with a '-' in front if the number is negative. - -int BN_ascii2bn(BIGNUM **bn, char *a); - The inverse of BN_bn2ascii. The function returns the number of - characters from 'a' were processed in generating a the bignum. - error is inticated by 0 being returned. The number is a - hex digit string, optionally with a leading '-'. If *bn - is null, a BIGNUM is created and returned via that variable. - -int BN_print_fp(FILE *fp, BIGNUM *a); - 'a' is printed to file pointer 'fp'. It is in the same format - that is output from BN_bn2ascii(). 0 is returned on error, - 1 if things are ok. - -int BN_print(BIO *bp, BIGNUM *a); - Same as BN_print except that the output is done to the SSLeay libraries - BIO routines. BN_print_fp() actually calls this function. - -Miscellaneous Routines. - -int BN_rand(BIGNUM *rnd, int bits, int top, int bottom); - This function returns in 'rnd' a random BIGNUM that is bits - long. If bottom is 1, the number returned is odd. If top is set, - the top 2 bits of the number are set. This is useful because if - this is set, 2 'n; bit numbers multiplied together will return a 2n - bit number. If top was not set, they could produce a 2n-1 bit - number. - -BIGNUM *BN_mod_inverse(BIGNUM *a, BIGNUM *n,BN_CTX *ctx); - This function create a new BIGNUM and returns it. This number - is the inverse mod 'n' of 'a'. By this it is meant that the - returned value 'r' satisfies (a*r)%n == 1. This function is - used in the generation of RSA keys. 'ctx', as per usual, - is used to hold temporary variables that are required by the - function. NULL is returned on error. - -int BN_gcd(BIGNUM *r,BIGNUM *a,BIGNUM *b,BN_CTX *ctx); - 'r' has the greatest common divisor of 'a' and 'b'. 'ctx' is - used for temporary variables and 0 is returned on error. - -int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(),BN_CTX *ctx, - char *cb_arg); - This function is used to check if a BIGNUM ('p') is prime. - It performs this test by using the Miller-Rabin randomised - primality test. This is a probalistic test that requires a - number of rounds to ensure the number is prime to a high - degree of probability. Since this can take quite some time, a - callback function can be passed and it will be called each - time 'p' passes a round of the prime testing. 'callback' will - be called as follows, callback(1,n,cb_arg) where n is the number of - the round, just passed. As per usual 'ctx' contains temporary - variables used. If ctx is NULL, it does not matter, a local version - will be malloced. This parameter is present to save some mallocing - inside the function but probably could be removed. - 0 is returned on error. - 'ncheck' is the number of Miller-Rabin tests to run. It is - suggested to use the value 'BN_prime_checks' by default. - -BIGNUM *BN_generate_prime( -int bits, -int strong, -BIGNUM *a, -BIGNUM *rems, -void (*callback)()); -char *cb_arg - This function is used to generate prime numbers. It returns a - new BIGNUM that has a high probability of being a prime. - 'bits' is the number of bits that - are to be in the prime. If 'strong' is true, the returned prime - will also be a strong prime ((p-1)/2 is also prime). - While searching for the prime ('p'), we - can add the requirement that the prime fill the following - condition p%a == rem. This can be used to help search for - primes with specific features, which is required when looking - for primes suitable for use with certain 'g' values in the - Diffie-Hellman key exchange algorithm. If 'a' is NULL, - this condition is not checked. If rem is NULL, rem is assumed - to be 1. Since this search for a prime - can take quite some time, if callback is not NULL, it is called - in the following situations. - We have a suspected prime (from a quick sieve), - callback(0,sus_prime++,cb_arg). Each item to be passed to BN_is_prime(). - callback(1,round++,cb_arg). Each successful 'round' in BN_is_prime(). - callback(2,round,cb_arg). For each successful BN_is_prime() test. - -Hints ------ - -DSA wants 64*32 to use word mont mul, but RSA wants to use full. - -==== callback.doc ======================================================== - -Callback functions used in SSLeay. - --------------------------- -The BIO library. - -Each BIO structure can have a callback defined against it. This callback is -called 2 times for each BIO 'function'. It is passed 6 parameters. -BIO_debug_callback() is an example callback which is defined in -crypto/buffer/bio_cb.c and is used in apps/dgst.c This is intended mostly -for debuging or to notify the application of IO. - -long BIO_debug_callback(BIO *bio,int cmd,char *argp,int argi,long argl, - long ret); -bio is the BIO being called, cmd is the type of BIO function being called. -Look at the BIO_CB_* defines in buffer.h. Argp and argi are the arguments -passed to BIO_read(), BIO_write, BIO_gets(), BIO_puts(). In the case of -BIO_ctrl(), argl is also defined. The first time the callback is called, -before the underlying function has been executed, 0 is passed as 'ret', and -if the return code from the callback is not > 0, the call is aborted -and the returned <= 0 value is returned. -The second time the callback is called, the 'cmd' value also has -BIO_CB_RETURN logically 'or'ed with it. The 'ret' value is the value returned -from the actuall function call and whatever the callback returns is returned -from the BIO function. - -BIO_set_callback(b,cb) can be used to set the callback function -(b is a BIO), and BIO_set_callback_arg(b,arg) can be used to -set the cb_arg argument in the BIO strucutre. This field is only intended -to be used by application, primarily in the callback function since it is -accessable since the BIO is passed. - --------------------------- -The PEM library. - -The pem library only really uses one type of callback, -static int def_callback(char *buf, int num, int verify); -which is used to return a password string if required. -'buf' is the buffer to put the string in. 'num' is the size of 'buf' -and 'verify' is used to indicate that the password should be checked. -This last flag is mostly used when reading a password for encryption. - -For all of these functions, a NULL callback will call the above mentioned -default callback. This default function does not work under Windows 3.1. -For other machines, it will use an application defined prompt string -(EVP_set_pw_prompt(), which defines a library wide prompt string) -if defined, otherwise it will use it's own PEM password prompt. -It will then call EVP_read_pw_string() to get a password from the console. -If your application wishes to use nice fancy windows to retrieve passwords, -replace this function. The callback should return the number of bytes read -into 'buf'. If the number of bytes <= 0, it is considered an error. - -Functions that take this callback are listed below. For the 'read' type -functions, the callback will only be required if the PEM data is encrypted. - -For the Write functions, normally a password can be passed in 'kstr', of -'klen' bytes which will be used if the 'enc' cipher is not NULL. If -'kstr' is NULL, the callback will be used to retrieve a password. - -int PEM_do_header (EVP_CIPHER_INFO *cipher, unsigned char *data,long *len, - int (*callback)()); -char *PEM_ASN1_read_bio(char *(*d2i)(),char *name,BIO *bp,char **x,int (*cb)()); -char *PEM_ASN1_read(char *(*d2i)(),char *name,FILE *fp,char **x,int (*cb)()); -int PEM_ASN1_write_bio(int (*i2d)(),char *name,BIO *bp,char *x, - EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)()); -int PEM_ASN1_write(int (*i2d)(),char *name,FILE *fp,char *x, - EVP_CIPHER *enc,unsigned char *kstr,int klen,int (*callback)()); -STACK *PEM_X509_INFO_read(FILE *fp, STACK *sk, int (*cb)()); -STACK *PEM_X509_INFO_read_bio(BIO *fp, STACK *sk, int (*cb)()); - -#define PEM_write_RSAPrivateKey(fp,x,enc,kstr,klen,cb) -#define PEM_write_DSAPrivateKey(fp,x,enc,kstr,klen,cb) -#define PEM_write_bio_RSAPrivateKey(bp,x,enc,kstr,klen,cb) -#define PEM_write_bio_DSAPrivateKey(bp,x,enc,kstr,klen,cb) -#define PEM_read_SSL_SESSION(fp,x,cb) -#define PEM_read_X509(fp,x,cb) -#define PEM_read_X509_REQ(fp,x,cb) -#define PEM_read_X509_CRL(fp,x,cb) -#define PEM_read_RSAPrivateKey(fp,x,cb) -#define PEM_read_DSAPrivateKey(fp,x,cb) -#define PEM_read_PrivateKey(fp,x,cb) -#define PEM_read_PKCS7(fp,x,cb) -#define PEM_read_DHparams(fp,x,cb) -#define PEM_read_bio_SSL_SESSION(bp,x,cb) -#define PEM_read_bio_X509(bp,x,cb) -#define PEM_read_bio_X509_REQ(bp,x,cb) -#define PEM_read_bio_X509_CRL(bp,x,cb) -#define PEM_read_bio_RSAPrivateKey(bp,x,cb) -#define PEM_read_bio_DSAPrivateKey(bp,x,cb) -#define PEM_read_bio_PrivateKey(bp,x,cb) -#define PEM_read_bio_PKCS7(bp,x,cb) -#define PEM_read_bio_DHparams(bp,x,cb) -int i2d_Netscape_RSA(RSA *a, unsigned char **pp, int (*cb)()); -RSA *d2i_Netscape_RSA(RSA **a, unsigned char **pp, long length, int (*cb)()); - -Now you will notice that macros like -#define PEM_write_X509(fp,x) \ - PEM_ASN1_write((int (*)())i2d_X509,PEM_STRING_X509,fp, \ - (char *)x, NULL,NULL,0,NULL) -Don't do encryption normally. If you want to PEM encrypt your X509 structure, -either just call PEM_ASN1_write directly or just define your own -macro variant. As you can see, this macro just sets all encryption related -parameters to NULL. - - --------------------------- -The SSL library. - -#define SSL_set_info_callback(ssl,cb) -#define SSL_CTX_set_info_callback(ctx,cb) -void callback(SSL *ssl,int location,int ret) -This callback is called each time around the SSL_connect()/SSL_accept() -state machine. So it will be called each time the SSL protocol progresses. -It is mostly present for use when debugging. When SSL_connect() or -SSL_accept() return, the location flag is SSL_CB_ACCEPT_EXIT or -SSL_CB_CONNECT_EXIT and 'ret' is the value about to be returned. -Have a look at the SSL_CB_* defines in ssl.h. If an info callback is defined -against the SSL_CTX, it is called unless there is one set against the SSL. -Have a look at -void client_info_callback() in apps/s_client() for an example. - -Certificate verification. -void SSL_set_verify(SSL *s, int mode, int (*callback) ()); -void SSL_CTX_set_verify(SSL_CTX *ctx,int mode,int (*callback)()); -This callback is used to help verify client and server X509 certificates. -It is actually passed to X509_cert_verify(), along with the SSL structure -so you have to read about X509_cert_verify() :-). The SSL_CTX version is used -if the SSL version is not defined. X509_cert_verify() is the function used -by the SSL part of the library to verify certificates. This function is -nearly always defined by the application. - -void SSL_CTX_set_cert_verify_cb(SSL_CTX *ctx, int (*cb)(),char *arg); -int callback(char *arg,SSL *s,X509 *xs,STACK *cert_chain); -This call is used to replace the SSLeay certificate verification code. -The 'arg' is kept in the SSL_CTX and is passed to the callback. -If the callback returns 0, the certificate is rejected, otherwise it -is accepted. The callback is replacing the X509_cert_verify() call. -This feature is not often used, but if you wished to implement -some totally different certificate authentication system, this 'hook' is -vital. - -SSLeay keeps a cache of session-ids against each SSL_CTX. These callbacks can -be used to notify the application when a SSL_SESSION is added to the cache -or to retrieve a SSL_SESSION that is not in the cache from the application. -#define SSL_CTX_sess_set_get_cb(ctx,cb) -SSL_SESSION *callback(SSL *s,char *session_id,int session_id_len,int *copy); -If defined, this callback is called to return the SESSION_ID for the -session-id in 'session_id', of 'session_id_len' bytes. 'copy' is set to 1 -if the server is to 'take a copy' of the SSL_SESSION structure. It is 0 -if the SSL_SESSION is being 'passed in' so the SSLeay library is now -responsible for 'free()ing' the structure. Basically it is used to indicate -if the reference count on the SSL_SESSION structure needs to be incremented. - -#define SSL_CTX_sess_set_new_cb(ctx,cb) -int callback(SSL *s, SSL_SESSION *sess); -When a new connection is established, if the SSL_SESSION is going to be added -to the cache, this callback is called. Return 1 if a 'copy' is required, -otherwise, return 0. This return value just causes the reference count -to be incremented (on return of a 1), this means the application does -not need to worry about incrementing the refernece count (and the -locking that implies in a multi-threaded application). - -void SSL_CTX_set_default_passwd_cb(SSL_CTX *ctx,int (*cb)()); -This sets the SSL password reading function. -It is mostly used for windowing applications -and used by PEM_read_bio_X509() and PEM_read_bio_RSAPrivateKey() -calls inside the SSL library. The only reason this is present is because the -calls to PEM_* functions is hidden in the SSLeay library so you have to -pass in the callback some how. - -#define SSL_CTX_set_client_cert_cb(ctx,cb) -int callback(SSL *s,X509 **x509, EVP_PKEY **pkey); -Called when a client certificate is requested but there is not one set -against the SSL_CTX or the SSL. If the callback returns 1, x509 and -pkey need to point to valid data. The library will free these when -required so if the application wants to keep these around, increment -their reference counts. If 0 is returned, no client cert is -available. If -1 is returned, it is assumed that the callback needs -to be called again at a later point in time. SSL_connect will return --1 and SSL_want_x509_lookup(ssl) returns true. Remember that -application data can be attached to an SSL structure via the -SSL_set_app_data(SSL *ssl,char *data) call. - --------------------------- -The X509 library. - -int X509_cert_verify(CERTIFICATE_CTX *ctx,X509 *xs, int (*cb)(), - int *error,char *arg,STACK *cert_chain); -int verify_callback(int ok,X509 *xs,X509 *xi,int depth,int error,char *arg, - STACK *cert_chain); - -X509_cert_verify() is used to authenticate X509 certificates. The 'ctx' holds -the details of the various caches and files used to locate certificates. -'xs' is the certificate to verify and 'cb' is the application callback (more -detail later). 'error' will be set to the error code and 'arg' is passed -to the 'cb' callback. Look at the VERIFY_* defines in crypto/x509/x509.h - -When ever X509_cert_verify() makes a 'negative' decision about a -certitificate, the callback is called. If everything checks out, the -callback is called with 'VERIFY_OK' or 'VERIFY_ROOT_OK' (for a self -signed cert that is not the passed certificate). - -The callback is passed the X509_cert_verify opinion of the certificate -in 'ok', the certificate in 'xs', the issuer certificate in 'xi', -the 'depth' of the certificate in the verification 'chain', the -VERIFY_* code in 'error' and the argument passed to X509_cert_verify() -in 'arg'. cert_chain is a list of extra certs to use if they are not -in the cache. - -The callback can be used to look at the error reason, and then return 0 -for an 'error' or '1' for ok. This will override the X509_cert_verify() -opinion of the certificates validity. Processing will continue depending on -the return value. If one just wishes to use the callback for informational -reason, just return the 'ok' parameter. - --------------------------- -The BN and DH library. - -BIGNUM *BN_generate_prime(int bits,int strong,BIGNUM *add, - BIGNUM *rem,void (*callback)(int,int)); -int BN_is_prime(BIGNUM *p,int nchecks,void (*callback)(int,int), - -Read doc/bn.doc for the description of these 2. - -DH *DH_generate_parameters(int prime_len,int generator, - void (*callback)(int,int)); -Read doc/bn.doc for the description of the callback, since it is just passed -to BN_generate_prime(), except that it is also called as -callback(3,0) by this function. - --------------------------- -The CRYPTO library. - -void CRYPTO_set_locking_callback(void (*func)(int mode,int type,char *file, - int line)); -void CRYPTO_set_add_lock_callback(int (*func)(int *num,int mount, - int type,char *file, int line)); -void CRYPTO_set_id_callback(unsigned long (*func)(void)); - -Read threads.doc for info on these ones. - - -==== cipher.doc ======================================================== - -The Cipher subroutines. - -These routines require "evp.h" to be included. - -These functions are a higher level interface to the various cipher -routines found in this library. As such, they allow the same code to be -used to encrypt and decrypt via different ciphers with only a change -in an initial parameter. These routines also provide buffering for block -ciphers. - -These routines all take a pointer to the following structure to specify -which cipher to use. If you wish to use a new cipher with these routines, -you would probably be best off looking an how an existing cipher is -implemented and copying it. At this point in time, I'm not going to go -into many details. This structure should be considered opaque - -typedef struct pem_cipher_st - { - int type; - int block_size; - int key_len; - int iv_len; - void (*enc_init)(); /* init for encryption */ - void (*dec_init)(); /* init for decryption */ - void (*do_cipher)(); /* encrypt data */ - } EVP_CIPHER; - -The type field is the object NID of the cipher type -(read the section on Objects for an explanation of what a NID is). -The cipher block_size is how many bytes need to be passed -to the cipher at a time. Key_len is the -length of the key the cipher requires and iv_len is the length of the -initialisation vector required. enc_init is the function -called to initialise the ciphers context for encryption and dec_init is the -function to initialise for decryption (they need to be different, especially -for the IDEA cipher). - -One reason for specifying the Cipher via a pointer to a structure -is that if you only use des-cbc, only the des-cbc routines will -be included when you link the program. If you passed an integer -that specified which cipher to use, the routine that mapped that -integer to a set of cipher functions would cause all the ciphers -to be link into the code. This setup also allows new ciphers -to be added by the application (with some restrictions). - -The thirteen ciphers currently defined in this library are - -EVP_CIPHER *EVP_des_ecb(); /* DES in ecb mode, iv=0, block=8, key= 8 */ -EVP_CIPHER *EVP_des_ede(); /* DES in ecb ede mode, iv=0, block=8, key=16 */ -EVP_CIPHER *EVP_des_ede3(); /* DES in ecb ede mode, iv=0, block=8, key=24 */ -EVP_CIPHER *EVP_des_cfb(); /* DES in cfb mode, iv=8, block=1, key= 8 */ -EVP_CIPHER *EVP_des_ede_cfb(); /* DES in ede cfb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_des_ede3_cfb();/* DES in ede cfb mode, iv=8, block=1, key=24 */ -EVP_CIPHER *EVP_des_ofb(); /* DES in ofb mode, iv=8, block=1, key= 8 */ -EVP_CIPHER *EVP_des_ede_ofb(); /* DES in ede ofb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_des_ede3_ofb();/* DES in ede ofb mode, iv=8, block=1, key=24 */ -EVP_CIPHER *EVP_des_cbc(); /* DES in cbc mode, iv=8, block=8, key= 8 */ -EVP_CIPHER *EVP_des_ede_cbc(); /* DES in cbc ede mode, iv=8, block=8, key=16 */ -EVP_CIPHER *EVP_des_ede3_cbc();/* DES in cbc ede mode, iv=8, block=8, key=24 */ -EVP_CIPHER *EVP_desx_cbc(); /* DES in desx cbc mode,iv=8, block=8, key=24 */ -EVP_CIPHER *EVP_rc4(); /* RC4, iv=0, block=1, key=16 */ -EVP_CIPHER *EVP_idea_ecb(); /* IDEA in ecb mode, iv=0, block=8, key=16 */ -EVP_CIPHER *EVP_idea_cfb(); /* IDEA in cfb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_idea_ofb(); /* IDEA in ofb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_idea_cbc(); /* IDEA in cbc mode, iv=8, block=8, key=16 */ -EVP_CIPHER *EVP_rc2_ecb(); /* RC2 in ecb mode, iv=0, block=8, key=16 */ -EVP_CIPHER *EVP_rc2_cfb(); /* RC2 in cfb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_rc2_ofb(); /* RC2 in ofb mode, iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_rc2_cbc(); /* RC2 in cbc mode, iv=8, block=8, key=16 */ -EVP_CIPHER *EVP_bf_ecb(); /* Blowfish in ecb mode,iv=0, block=8, key=16 */ -EVP_CIPHER *EVP_bf_cfb(); /* Blowfish in cfb mode,iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_bf_ofb(); /* Blowfish in ofb mode,iv=8, block=1, key=16 */ -EVP_CIPHER *EVP_bf_cbc(); /* Blowfish in cbc mode,iv=8, block=8, key=16 */ - -The meaning of the compound names is as follows. -des The base cipher is DES. -idea The base cipher is IDEA -rc4 The base cipher is RC4-128 -rc2 The base cipher is RC2-128 -ecb Electronic Code Book form of the cipher. -cbc Cipher Block Chaining form of the cipher. -cfb 64 bit Cipher Feedback form of the cipher. -ofb 64 bit Output Feedback form of the cipher. -ede The cipher is used in Encrypt, Decrypt, Encrypt mode. The first - and last keys are the same. -ede3 The cipher is used in Encrypt, Decrypt, Encrypt mode. - -All the Cipher routines take a EVP_CIPHER_CTX pointer as an argument. -The state of the cipher is kept in this structure. - -typedef struct EVP_CIPHER_Ctx_st - { - EVP_CIPHER *cipher; - int encrypt; /* encrypt or decrypt */ - int buf_len; /* number we have left */ - unsigned char buf[8]; - union { - .... /* cipher specific stuff */ - } c; - } EVP_CIPHER_CTX; - -Cipher is a pointer the the EVP_CIPHER for the current context. The encrypt -flag indicates encryption or decryption. buf_len is the number of bytes -currently being held in buf. -The 'c' union holds the cipher specify context. - -The following functions are to be used. - -int EVP_read_pw_string( -char *buf, -int len, -char *prompt, -int verify, - This function is the same as des_read_pw_string() (des.doc). - -void EVP_set_pw_prompt(char *prompt); - This function sets the 'default' prompt to use to use in - EVP_read_pw_string when the prompt parameter is NULL. If the - prompt parameter is NULL, this 'default prompt' feature is turned - off. Be warned, this is a global variable so weird things - will happen if it is used under Win16 and care must be taken - with a multi-threaded version of the library. - -char *EVP_get_pw_prompt(); - This returns a pointer to the default prompt string. NULL - if it is not set. - -int EVP_BytesToKey( -EVP_CIPHER *type, -EVP_MD *md, -unsigned char *salt, -unsigned char *data, -int datal, -int count, -unsigned char *key, -unsigned char *iv); - This function is used to generate a key and an initialisation vector - for a specified cipher from a key string and a salt. Type - specifies the cipher the 'key' is being generated for. Md is the - message digest algorithm to use to generate the key and iv. The salt - is an optional 8 byte object that is used to help seed the key - generator. - If the salt value is NULL, it is just not used. Datal is the - number of bytes to use from 'data' in the key generation. - This function returns the key size for the specified cipher, if - data is NULL, this value is returns and no other - computation is performed. Count is - the number of times to loop around the key generator. I would - suggest leaving it's value as 1. Key and iv are the structures to - place the returning iv and key in. If they are NULL, no value is - generated for that particular value. - The algorithm used is as follows - - /* M[] is an array of message digests - * MD() is the message digest function */ - M[0]=MD(data . salt); - for (i=1; i<count; i++) M[0]=MD(M[0]); - - i=1 - while (data still needed for key and iv) - { - M[i]=MD(M[i-1] . data . salt); - for (i=1; i<count; i++) M[i]=MD(M[i]); - i++; - } - - If the salt is NULL, it is not used. - The digests are concatenated together. - M = M[0] . M[1] . M[2] ....... - - For key= 8, iv=8 => key=M[0.. 8], iv=M[ 9 .. 16]. - For key=16, iv=0 => key=M[0..16]. - For key=16, iv=8 => key=M[0..16], iv=M[17 .. 24]. - For key=24, iv=8 => key=M[0..24], iv=M[25 .. 32]. - - This routine will produce DES-CBC keys and iv that are compatible - with the PKCS-5 standard when md2 or md5 are used. If md5 is - used, the salt is NULL and count is 1, this routine will produce - the password to key mapping normally used with RC4. - I have attempted to logically extend the PKCS-5 standard to - generate keys and iv for ciphers that require more than 16 bytes, - if anyone knows what the correct standard is, please inform me. - When using sha or sha1, things are a bit different under this scheme, - since sha produces a 20 byte digest. So for ciphers requiring - 24 bits of data, 20 will come from the first MD and 4 will - come from the second. - - I have considered having a separate function so this 'routine' - can be used without the requirement of passing a EVP_CIPHER *, - but I have decided to not bother. If you wish to use the - function without official EVP_CIPHER structures, just declare - a local one and set the key_len and iv_len fields to the - length you desire. - -The following routines perform encryption and decryption 'by parts'. By -this I mean that there are groups of 3 routines. An Init function that is -used to specify a cipher and initialise data structures. An Update routine -that does encryption/decryption, one 'chunk' at a time. And finally a -'Final' function that finishes the encryption/decryption process. -All these functions take a EVP_CIPHER pointer to specify which cipher to -encrypt/decrypt with. They also take a EVP_CIPHER_CTX object as an -argument. This structure is used to hold the state information associated -with the operation in progress. - -void EVP_EncryptInit( -EVP_CIPHER_CTX *ctx, -EVP_CIPHER *type, -unsigned char *key, -unsigned char *iv); - This function initialise a EVP_CIPHER_CTX for encryption using the - cipher passed in the 'type' field. The cipher is initialised to use - 'key' as the key and 'iv' for the initialisation vector (if one is - required). If the type, key or iv is NULL, the value currently in the - EVP_CIPHER_CTX is reused. So to perform several decrypt - using the same cipher, key and iv, initialise with the cipher, - key and iv the first time and then for subsequent calls, - reuse 'ctx' but pass NULL for type, key and iv. You must make sure - to pass a key that is large enough for a particular cipher. I - would suggest using the EVP_BytesToKey() function. - -void EVP_EncryptUpdate( -EVP_CIPHER_CTX *ctx, -unsigned char *out, -int *outl, -unsigned char *in, -int inl); - This function takes 'inl' bytes from 'in' and outputs bytes - encrypted by the cipher 'ctx' was initialised with into 'out'. The - number of bytes written to 'out' is put into outl. If a particular - cipher encrypts in blocks, less or more bytes than input may be - output. Currently the largest block size used by supported ciphers - is 8 bytes, so 'out' should have room for 'inl+7' bytes. Normally - EVP_EncryptInit() is called once, followed by lots and lots of - calls to EVP_EncryptUpdate, followed by a single EVP_EncryptFinal - call. - -void EVP_EncryptFinal( -EVP_CIPHER_CTX *ctx, -unsigned char *out, -int *outl); - Because quite a large number of ciphers are block ciphers, there is - often an incomplete block to write out at the end of the - encryption. EVP_EncryptFinal() performs processing on this last - block. The last block in encoded in such a way that it is possible - to determine how many bytes in the last block are valid. For 8 byte - block size ciphers, if only 5 bytes in the last block are valid, the - last three bytes will be filled with the value 3. If only 2 were - valid, the other 6 would be filled with sixes. If all 8 bytes are - valid, a extra 8 bytes are appended to the cipher stream containing - nothing but 8 eights. These last bytes are output into 'out' and - the number of bytes written is put into 'outl' These last bytes - are output into 'out' and the number of bytes written is put into - 'outl'. This form of block cipher finalisation is compatible with - PKCS-5. Please remember that even if you are using ciphers like - RC4 that has no blocking and so the function will not write - anything into 'out', it would still be a good idea to pass a - variable for 'out' that can hold 8 bytes just in case the cipher is - changed some time in the future. It should also be remembered - that the EVP_CIPHER_CTX contains the password and so when one has - finished encryption with a particular EVP_CIPHER_CTX, it is good - practice to zero the structure - (ie. memset(ctx,0,sizeof(EVP_CIPHER_CTX)). - -void EVP_DecryptInit( -EVP_CIPHER_CTX *ctx, -EVP_CIPHER *type, -unsigned char *key, -unsigned char *iv); - This function is basically the same as EVP_EncryptInit() accept that - is prepares the EVP_CIPHER_CTX for decryption. - -void EVP_DecryptUpdate( -EVP_CIPHER_CTX *ctx, -unsigned char *out, -int *outl, -unsigned char *in, -int inl); - This function is basically the same as EVP_EncryptUpdate() - except that it performs decryption. There is one - fundamental difference though. 'out' can not be the same as - 'in' for any ciphers with a block size greater than 1 if more - than one call to EVP_DecryptUpdate() will be made. This - is because this routine can hold a 'partial' block between - calls. When a partial block is decrypted (due to more bytes - being passed via this function, they will be written to 'out' - overwriting the input bytes in 'in' that have not been read - yet. From this it should also be noted that 'out' should - be at least one 'block size' larger than 'inl'. This problem - only occurs on the second and subsequent call to - EVP_DecryptUpdate() when using a block cipher. - -int EVP_DecryptFinal( -EVP_CIPHER_CTX *ctx, -unsigned char *out, -int *outl); - This function is different to EVP_EncryptFinal in that it 'removes' - any padding bytes appended when the data was encrypted. Due to the - way in which 1 to 8 bytes may have been appended when encryption - using a block cipher, 'out' can end up with 0 to 7 bytes being put - into it. When decoding the padding bytes, it is possible to detect - an incorrect decryption. If the decryption appears to be wrong, 0 - is returned. If everything seems ok, 1 is returned. For ciphers - with a block size of 1 (RC4), this function would normally not - return any bytes and would always return 1. Just because this - function returns 1 does not mean the decryption was correct. It - would normally be wrong due to either the wrong key/iv or - corruption of the cipher data fed to EVP_DecryptUpdate(). - As for EVP_EncryptFinal, it is a good idea to zero the - EVP_CIPHER_CTX after use since the structure contains the key used - to decrypt the data. - -The following Cipher routines are convenience routines that call either -EVP_EncryptXxx or EVP_DecryptXxx depending on weather the EVP_CIPHER_CTX -was setup to encrypt or decrypt. - -void EVP_CipherInit( -EVP_CIPHER_CTX *ctx, -EVP_CIPHER *type, -unsigned char *key, -unsigned char *iv, -int enc); - This function take arguments that are the same as EVP_EncryptInit() - and EVP_DecryptInit() except for the extra 'enc' flag. If 1, the - EVP_CIPHER_CTX is setup for encryption, if 0, decryption. - -void EVP_CipherUpdate( -EVP_CIPHER_CTX *ctx, -unsigned char *out, -int *outl, -unsigned char *in, -int inl); - Again this function calls either EVP_EncryptUpdate() or - EVP_DecryptUpdate() depending on state in the 'ctx' structure. - As noted for EVP_DecryptUpdate(), when this routine is used - for decryption with block ciphers, 'out' should not be the - same as 'in'. - -int EVP_CipherFinal( -EVP_CIPHER_CTX *ctx, -unsigned char *outm, -int *outl); - This routine call EVP_EncryptFinal() or EVP_DecryptFinal() - depending on the state information in 'ctx'. 1 is always returned - if the mode is encryption, otherwise the return value is the return - value of EVP_DecryptFinal(). - -==== cipher.m ======================================================== - -Date: Tue, 15 Oct 1996 08:16:14 +1000 (EST) -From: Eric Young <eay@mincom.com> -X-Sender: eay@orb -To: Roland Haring <rharing@tandem.cl> -Cc: ssl-users@mincom.com -Subject: Re: Symmetric encryption with ssleay -In-Reply-To: <m0vBpyq-00001aC@tandemnet.tandem.cl> -Message-Id: <Pine.SOL.3.91.961015075623.11394A-100000@orb> -Mime-Version: 1.0 -Content-Type: TEXT/PLAIN; charset=US-ASCII -Sender: ssl-lists-owner@mincom.com -Precedence: bulk -Status: RO -X-Status: - -On Fri, 11 Oct 1996, Roland Haring wrote: -> THE_POINT: -> Would somebody be so kind to give me the minimum basic -> calls I need to do to libcrypto.a to get some text encrypted -> and decrypted again? ...hopefully with code included to do -> base64 encryption and decryption ... e.g. that sign-it.c code -> posted some while ago was a big help :-) (please, do not point -> me to apps/enc.c where I suspect my Heissenbug to be hidden :-) - -Ok, the base64 encoding stuff in 'enc.c' does the wrong thing sometimes -when the data is less than a line long (this is for decoding). I'll dig -up the exact fix today and post it. I am taking longer on 0.6.5 than I -intended so I'll just post this patch. - -The documentation to read is in -doc/cipher.doc, -doc/encode.doc (very sparse :-). -and perhaps -doc/digest.doc, - -The basic calls to encrypt with say triple DES are - -Given -char key[EVP_MAX_KEY_LENGTH]; -char iv[EVP_MAX_IV_LENGTH]; -EVP_CIPHER_CTX ctx; -unsigned char out[512+8]; -int outl; - -/* optional generation of key/iv data from text password using md5 - * via an upward compatable verson of PKCS#5. */ -EVP_BytesToKey(EVP_des_ede3_cbc,EVP_md5,NULL,passwd,strlen(passwd), - key,iv); - -/* Initalise the EVP_CIPHER_CTX */ -EVP_EncryptInit(ctx,EVP_des_ede3_cbc,key,iv); - -while (....) - { - /* This is processing 512 bytes at a time, the bytes are being - * copied into 'out', outl bytes are output. 'out' should not be the - * same as 'in' for reasons mentioned in the documentation. */ - EVP_EncryptUpdate(ctx,out,&outl,in,512); - } - -/* Output the last 'block'. If the cipher is a block cipher, the last - * block is encoded in such a way so that a wrong decryption will normally be - * detected - again, one of the PKCS standards. */ - -EVP_EncryptFinal(ctx,out,&outl); - -To decrypt, use the EVP_DecryptXXXXX functions except that EVP_DecryptFinal() -will return 0 if the decryption fails (only detectable on block ciphers). - -You can also use -EVP_CipherInit() -EVP_CipherUpdate() -EVP_CipherFinal() -which does either encryption or decryption depending on an extra -parameter to EVP_CipherInit(). - - -To do the base64 encoding, -EVP_EncodeInit() -EVP_EncodeUpdate() -EVP_EncodeFinal() - -EVP_DecodeInit() -EVP_DecodeUpdate() -EVP_DecodeFinal() - -where the encoding is quite simple, but the decoding can be a bit more -fun (due to dud input). - -EVP_DecodeUpdate() returns -1 for an error on an input line, 0 if the -'last line' was just processed, and 1 if more lines should be submitted. - -EVP_DecodeFinal() returns -1 for an error or 1 if things are ok. - -So the loop becomes -EVP_DecodeInit(....) -for (;;) - { - i=EVP_DecodeUpdate(....); - if (i < 0) goto err; - - /* process the data */ - - if (i == 0) break; - } -EVP_DecodeFinal(....); -/* process the data */ - -The problem in 'enc.c' is that I was stuff the processing up after the -EVP_DecodeFinal(...) when the for(..) loop was not being run (one line of -base64 data) and this was because 'enc.c' tries to scan over a file until -it hits the first valid base64 encoded line. - -hope this helps a bit. -eric --- -Eric Young | BOOL is tri-state according to Bill Gates. -AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage(). - -==== conf.doc ======================================================== - -The CONF library. - -The CONF library is a simple set of routines that can be used to configure -programs. It is a superset of the genenv() function with some extra -structure. - -The library consists of 5 functions. - -LHASH *CONF_load(LHASH *config,char *file); -This function is called to load in a configuration file. Multiple -configuration files can be loaded, with each subsequent 'load' overwriting -any already defined 'variables'. If there is an error, NULL is returned. -If config is NULL, a new LHASH structure is created and returned, otherwise -the new data in the 'file' is loaded into the 'config' structure. - -void CONF_free(LHASH *config); -This function free()s the data in config. - -char *CONF_get_string(LHASH *config,char *section,char *name); -This function returns the string found in 'config' that corresponds to the -'section' and 'name' specified. Classes and the naming system used will be -discussed later in this document. If the variable is not defined, an NULL -is returned. - -long CONF_get_long(LHASH *config,char *section, char *name); -This function is the same as CONF_get_string() except that it converts the -string to an long and returns it. If variable is not a number or the -variable does not exist, 0 is returned. This is a little problematic but I -don't know of a simple way around it. - -STACK *CONF_get_section(LHASH *config, char *section); -This function returns a 'stack' of CONF_VALUE items that are all the -items defined in a particular section. DO NOT free() any of the -variable returned. They will disappear when CONF_free() is called. - -The 'lookup' model. -The configuration file is divided into 'sections'. Each section is started by -a line of the form '[ section ]'. All subsequent variable definitions are -of this section. A variable definition is a simple alpha-numeric name -followed by an '=' and then the data. A section or variable name can be -described by a regular expression of the following form '[A-Za-z0-9_]+'. -The value of the variable is the text after the '=' until the end of the -line, stripped of leading and trailing white space. -At this point I should mention that a '#' is a comment character, \ is the -escape character, and all three types of quote can be used to stop any -special interpretation of the data. -Now when the data is being loaded, variable expansion can occur. This is -done by expanding any $NAME sequences into the value represented by the -variable NAME. If the variable is not in the current section, the different -section can be specified by using the $SECTION::NAME form. The ${NAME} form -also works and is very useful for expanding variables inside strings. - -When a variable is looked up, there are 2 special section. 'default', which -is the initial section, and 'ENV' which is the processes environment -variables (accessed via getenv()). When a variable is looked up, it is -first 'matched' with it's section (if one was specified), if this fails, the -'default' section is matched. -If the 'lhash' variable passed was NULL, the environment is searched. - -Now why do we bother with sections? So we can have multiple programs using -the same configuration file, or multiple instances of the same program -using different variables. It also provides a nice mechanism to override -the processes environment variables (eg ENV::HOME=/tmp). If there is a -program specific variable missing, we can have default values. -Multiple configuration files can be loaded, with each new value clearing -any predefined values. A system config file can provide 'default' values, -and application/usr specific files can provide overriding values. - -Examples - -# This is a simple example -SSLEAY_HOME = /usr/local/ssl -ENV::PATH = $SSLEAY_HOME/bin:$PATH # override my path - -[X509] -cert_dir = $SSLEAY_HOME/certs # /usr/local/ssl/certs - -[SSL] -CIPHER = DES-EDE-MD5:RC4-MD5 -USER_CERT = $HOME/${USER}di'r 5' # /home/eay/eaydir 5 -USER_CERT = $HOME/\${USER}di\'r # /home/eay/${USER}di'r -USER_CERT = "$HOME/${US"ER}di\'r # $HOME/${USER}di'r - -TEST = 1234\ -5678\ -9ab # TEST=123456789ab -TTT = 1234\n\n # TTT=1234<nl><nl> - - - -==== des.doc ======================================================== - -The DES library. - -Please note that this library was originally written to operate with -eBones, a version of Kerberos that had had encryption removed when it left -the USA and then put back in. As such there are some routines that I will -advise not using but they are still in the library for historical reasons. -For all calls that have an 'input' and 'output' variables, they can be the -same. - -This library requires the inclusion of 'des.h'. - -All of the encryption functions take what is called a des_key_schedule as an -argument. A des_key_schedule is an expanded form of the des key. -A des_key is 8 bytes of odd parity, the type used to hold the key is a -des_cblock. A des_cblock is an array of 8 bytes, often in this library -description I will refer to input bytes when the function specifies -des_cblock's as input or output, this just means that the variable should -be a multiple of 8 bytes. - -The define DES_ENCRYPT is passed to specify encryption, DES_DECRYPT to -specify decryption. The functions and global variable are as follows: - -int des_check_key; - DES keys are supposed to be odd parity. If this variable is set to - a non-zero value, des_set_key() will check that the key has odd - parity and is not one of the known weak DES keys. By default this - variable is turned off; - -void des_set_odd_parity( -des_cblock *key ); - This function takes a DES key (8 bytes) and sets the parity to odd. - -int des_is_weak_key( -des_cblock *key ); - This function returns a non-zero value if the DES key passed is a - weak, DES key. If it is a weak key, don't use it, try a different - one. If you are using 'random' keys, the chances of hitting a weak - key are 1/2^52 so it is probably not worth checking for them. - -int des_set_key( -des_cblock *key, -des_key_schedule schedule); - Des_set_key converts an 8 byte DES key into a des_key_schedule. - A des_key_schedule is an expanded form of the key which is used to - perform actual encryption. It can be regenerated from the DES key - so it only needs to be kept when encryption or decryption is about - to occur. Don't save or pass around des_key_schedule's since they - are CPU architecture dependent, DES keys are not. If des_check_key - is non zero, zero is returned if the key has the wrong parity or - the key is a weak key, else 1 is returned. - -int des_key_sched( -des_cblock *key, -des_key_schedule schedule); - An alternative name for des_set_key(). - -int des_rw_mode; /* defaults to DES_PCBC_MODE */ - This flag holds either DES_CBC_MODE or DES_PCBC_MODE (default). - This specifies the function to use in the enc_read() and enc_write() - functions. - -void des_encrypt( -unsigned long *data, -des_key_schedule ks, -int enc); - This is the DES encryption function that gets called by just about - every other DES routine in the library. You should not use this - function except to implement 'modes' of DES. I say this because the - functions that call this routine do the conversion from 'char *' to - long, and this needs to be done to make sure 'non-aligned' memory - access do not occur. The characters are loaded 'little endian', - have a look at my source code for more details on how I use this - function. - Data is a pointer to 2 unsigned long's and ks is the - des_key_schedule to use. enc, is non zero specifies encryption, - zero if decryption. - -void des_encrypt2( -unsigned long *data, -des_key_schedule ks, -int enc); - This functions is the same as des_encrypt() except that the DES - initial permutation (IP) and final permutation (FP) have been left - out. As for des_encrypt(), you should not use this function. - It is used by the routines in my library that implement triple DES. - IP() des_encrypt2() des_encrypt2() des_encrypt2() FP() is the same - as des_encrypt() des_encrypt() des_encrypt() except faster :-). - -void des_ecb_encrypt( -des_cblock *input, -des_cblock *output, -des_key_schedule ks, -int enc); - This is the basic Electronic Code Book form of DES, the most basic - form. Input is encrypted into output using the key represented by - ks. If enc is non zero (DES_ENCRYPT), encryption occurs, otherwise - decryption occurs. Input is 8 bytes long and output is 8 bytes. - (the des_cblock structure is 8 chars). - -void des_ecb3_encrypt( -des_cblock *input, -des_cblock *output, -des_key_schedule ks1, -des_key_schedule ks2, -des_key_schedule ks3, -int enc); - This is the 3 key EDE mode of ECB DES. What this means is that - the 8 bytes of input is encrypted with ks1, decrypted with ks2 and - then encrypted again with ks3, before being put into output; - C=E(ks3,D(ks2,E(ks1,M))). There is a macro, des_ecb2_encrypt() - that only takes 2 des_key_schedules that implements, - C=E(ks1,D(ks2,E(ks1,M))) in that the final encrypt is done with ks1. - -void des_cbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule ks, -des_cblock *ivec, -int enc); - This routine implements DES in Cipher Block Chaining mode. - Input, which should be a multiple of 8 bytes is encrypted - (or decrypted) to output which will also be a multiple of 8 bytes. - The number of bytes is in length (and from what I've said above, - should be a multiple of 8). If length is not a multiple of 8, I'm - not being held responsible :-). ivec is the initialisation vector. - This function does not modify this variable. To correctly implement - cbc mode, you need to do one of 2 things; copy the last 8 bytes of - cipher text for use as the next ivec in your application, - or use des_ncbc_encrypt(). - Only this routine has this problem with updating the ivec, all - other routines that are implementing cbc mode update ivec. - -void des_ncbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule sk, -des_cblock *ivec, -int enc); - For historical reasons, des_cbc_encrypt() did not update the - ivec with the value requires so that subsequent calls to - des_cbc_encrypt() would 'chain'. This was needed so that the same - 'length' values would not need to be used when decrypting. - des_ncbc_encrypt() does the right thing. It is the same as - des_cbc_encrypt accept that ivec is updates with the correct value - to pass in subsequent calls to des_ncbc_encrypt(). I advise using - des_ncbc_encrypt() instead of des_cbc_encrypt(); - -void des_xcbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule sk, -des_cblock *ivec, -des_cblock *inw, -des_cblock *outw, -int enc); - This is RSA's DESX mode of DES. It uses inw and outw to - 'whiten' the encryption. inw and outw are secret (unlike the iv) - and are as such, part of the key. So the key is sort of 24 bytes. - This is much better than cbc des. - -void des_3cbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule sk1, -des_key_schedule sk2, -des_cblock *ivec1, -des_cblock *ivec2, -int enc); - This function is flawed, do not use it. I have left it in the - library because it is used in my des(1) program and will function - correctly when used by des(1). If I removed the function, people - could end up unable to decrypt files. - This routine implements outer triple cbc encryption using 2 ks and - 2 ivec's. Use des_ede2_cbc_encrypt() instead. - -void des_ede3_cbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule ks1, -des_key_schedule ks2, -des_key_schedule ks3, -des_cblock *ivec, -int enc); - This function implements outer triple CBC DES encryption with 3 - keys. What this means is that each 'DES' operation - inside the cbc mode is really an C=E(ks3,D(ks2,E(ks1,M))). - Again, this is cbc mode so an ivec is requires. - This mode is used by SSL. - There is also a des_ede2_cbc_encrypt() that only uses 2 - des_key_schedule's, the first being reused for the final - encryption. C=E(ks1,D(ks2,E(ks1,M))). This form of triple DES - is used by the RSAref library. - -void des_pcbc_encrypt( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule ks, -des_cblock *ivec, -int enc); - This is Propagating Cipher Block Chaining mode of DES. It is used - by Kerberos v4. It's parameters are the same as des_ncbc_encrypt(). - -void des_cfb_encrypt( -unsigned char *in, -unsigned char *out, -int numbits, -long length, -des_key_schedule ks, -des_cblock *ivec, -int enc); - Cipher Feedback Back mode of DES. This implementation 'feeds back' - in numbit blocks. The input (and output) is in multiples of numbits - bits. numbits should to be a multiple of 8 bits. Length is the - number of bytes input. If numbits is not a multiple of 8 bits, - the extra bits in the bytes will be considered padding. So if - numbits is 12, for each 2 input bytes, the 4 high bits of the - second byte will be ignored. So to encode 72 bits when using - a numbits of 12 take 12 bytes. To encode 72 bits when using - numbits of 9 will take 16 bytes. To encode 80 bits when using - numbits of 16 will take 10 bytes. etc, etc. This padding will - apply to both input and output. - - -void des_cfb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks, -des_cblock *ivec, -int *num, -int enc); - This is one of the more useful functions in this DES library, it - implements CFB mode of DES with 64bit feedback. Why is this - useful you ask? Because this routine will allow you to encrypt an - arbitrary number of bytes, no 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. num contains 'how far' we are though ivec. If this does - not make much sense, read more about cfb mode of DES :-). - -void des_ede3_cfb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks1, -des_key_schedule ks2, -des_key_schedule ks3, -des_cblock *ivec, -int *num, -int enc); - Same as des_cfb64_encrypt() accept that the DES operation is - triple DES. As usual, there is a macro for - des_ede2_cfb64_encrypt() which reuses ks1. - -void des_ofb_encrypt( -unsigned char *in, -unsigned char *out, -int numbits, -long length, -des_key_schedule ks, -des_cblock *ivec); - This is a implementation of Output Feed Back mode of DES. It is - the same as des_cfb_encrypt() in that numbits is the size of the - units dealt with during input and output (in bits). - -void des_ofb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks, -des_cblock *ivec, -int *num); - The same as des_cfb64_encrypt() except that it is Output Feed Back - mode. - -void des_ede3_ofb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks1, -des_key_schedule ks2, -des_key_schedule ks3, -des_cblock *ivec, -int *num); - Same as des_ofb64_encrypt() accept that the DES operation is - triple DES. As usual, there is a macro for - des_ede2_ofb64_encrypt() which reuses ks1. - -int des_read_pw_string( -char *buf, -int length, -char *prompt, -int verify); - This routine is used to get a password from the terminal with echo - turned off. Buf is where the string will end up and length is the - size of buf. Prompt is a string presented to the 'user' and if - verify is set, the key is asked for twice and unless the 2 copies - match, an error is returned. A return code of -1 indicates a - system error, 1 failure due to use interaction, and 0 is success. - -unsigned long des_cbc_cksum( -des_cblock *input, -des_cblock *output, -long length, -des_key_schedule ks, -des_cblock *ivec); - This function produces an 8 byte checksum from input that it puts in - output and returns the last 4 bytes as a long. The checksum is - generated via cbc mode of DES in which only the last 8 byes are - kept. I would recommend not using this function but instead using - the EVP_Digest routines, or at least using MD5 or SHA. This - function is used by Kerberos v4 so that is why it stays in the - library. - -char *des_fcrypt( -const char *buf, -const char *salt -char *ret); - This is my fast version of the unix crypt(3) function. This version - takes only a small amount of space relative to other fast - crypt() implementations. This is different to the normal crypt - in that the third parameter is the buffer that the return value - is written into. It needs to be at least 14 bytes long. This - function is thread safe, unlike the normal crypt. - -char *crypt( -const char *buf, -const char *salt); - This function calls des_fcrypt() with a static array passed as the - third parameter. This emulates the normal non-thread safe semantics - of crypt(3). - -void des_string_to_key( -char *str, -des_cblock *key); - This function takes str and converts it into a DES key. I would - recommend using MD5 instead and use the first 8 bytes of output. - When I wrote the first version of these routines back in 1990, MD5 - did not exist but I feel these routines are still sound. This - routines is compatible with the one in MIT's libdes. - -void des_string_to_2keys( -char *str, -des_cblock *key1, -des_cblock *key2); - This function takes str and converts it into 2 DES keys. - I would recommend using MD5 and using the 16 bytes as the 2 keys. - I have nothing against these 2 'string_to_key' routines, it's just - that if you say that your encryption key is generated by using the - 16 bytes of an MD5 hash, every-one knows how you generated your - keys. - -int des_read_password( -des_cblock *key, -char *prompt, -int verify); - This routine combines des_read_pw_string() with des_string_to_key(). - -int des_read_2passwords( -des_cblock *key1, -des_cblock *key2, -char *prompt, -int verify); - This routine combines des_read_pw_string() with des_string_to_2key(). - -void des_random_seed( -des_cblock key); - This routine sets a starting point for des_random_key(). - -void des_random_key( -des_cblock ret); - This function return a random key. Make sure to 'seed' the random - number generator (with des_random_seed()) before using this function. - I personally now use a MD5 based random number system. - -int des_enc_read( -int fd, -char *buf, -int len, -des_key_schedule ks, -des_cblock *iv); - This function will write to a file descriptor the encrypted data - from buf. This data will be preceded by a 4 byte 'byte count' and - will be padded out to 8 bytes. The encryption is either CBC of - PCBC depending on the value of des_rw_mode. If it is DES_PCBC_MODE, - pcbc is used, if DES_CBC_MODE, cbc is used. The default is to use - DES_PCBC_MODE. - -int des_enc_write( -int fd, -char *buf, -int len, -des_key_schedule ks, -des_cblock *iv); - This routines read stuff written by des_enc_read() and decrypts it. - I have used these routines quite a lot but I don't believe they are - suitable for non-blocking io. If you are after a full - authentication/encryption over networks, have a look at SSL instead. - -unsigned long des_quad_cksum( -des_cblock *input, -des_cblock *output, -long length, -int out_count, -des_cblock *seed); - This is a function from Kerberos v4 that is not anything to do with - DES but was needed. It is a cksum that is quicker to generate than - des_cbc_cksum(); I personally would use MD5 routines now. -===== -Modes of DES -Quite a bit of the following information has been taken from - AS 2805.5.2 - Australian Standard - Electronic funds transfer - Requirements for interfaces, - Part 5.2: Modes of operation for an n-bit block cipher algorithm - Appendix A - -There are several different modes in which DES can be used, they are -as follows. - -Electronic Codebook Mode (ECB) (des_ecb_encrypt()) -- 64 bits are enciphered at a time. -- The order of the blocks can be rearranged without detection. -- The same plaintext block always produces the same ciphertext block - (for the same key) making it vulnerable to a 'dictionary attack'. -- An error will only affect one ciphertext block. - -Cipher Block Chaining Mode (CBC) (des_cbc_encrypt()) -- a multiple of 64 bits are enciphered at a time. -- The CBC mode produces the same ciphertext whenever the same - plaintext is encrypted using the same key and starting variable. -- The chaining operation makes the ciphertext blocks dependent on the - current and all preceding plaintext blocks and therefore blocks can not - be rearranged. -- The use of different starting variables prevents the same plaintext - enciphering to the same ciphertext. -- An error will affect the current and the following ciphertext blocks. - -Cipher Feedback Mode (CFB) (des_cfb_encrypt()) -- a number of bits (j) <= 64 are enciphered at a time. -- The CFB mode produces the same ciphertext whenever the same - plaintext is encrypted using the same key and starting variable. -- The chaining operation makes the ciphertext variables dependent on the - current and all preceding variables and therefore j-bit variables are - chained together and can not be rearranged. -- The use of different starting variables prevents the same plaintext - enciphering to the same ciphertext. -- The strength of the CFB mode depends on the size of k (maximal if - j == k). In my implementation this is always the case. -- Selection of a small value for j will require more cycles through - the encipherment algorithm per unit of plaintext and thus cause - greater processing overheads. -- Only multiples of j bits can be enciphered. -- An error will affect the current and the following ciphertext variables. - -Output Feedback Mode (OFB) (des_ofb_encrypt()) -- a number of bits (j) <= 64 are enciphered at a time. -- The OFB mode produces the same ciphertext whenever the same - plaintext enciphered using the same key and starting variable. More - over, in the OFB mode the same key stream is produced when the same - key and start variable are used. Consequently, for security reasons - a specific start variable should be used only once for a given key. -- The absence of chaining makes the OFB more vulnerable to specific attacks. -- The use of different start variables values prevents the same - plaintext enciphering to the same ciphertext, by producing different - key streams. -- Selection of a small value for j will require more cycles through - the encipherment algorithm per unit of plaintext and thus cause - greater processing overheads. -- Only multiples of j bits can be enciphered. -- OFB mode of operation does not extend ciphertext errors in the - resultant plaintext output. Every bit error in the ciphertext causes - only one bit to be in error in the deciphered plaintext. -- OFB mode is not self-synchronising. If the two operation of - encipherment and decipherment get out of synchronism, the system needs - to be re-initialised. -- Each re-initialisation should use a value of the start variable - different from the start variable values used before with the same - key. The reason for this is that an identical bit stream would be - produced each time from the same parameters. This would be - susceptible to a ' known plaintext' attack. - -Triple ECB Mode (des_ecb3_encrypt()) -- Encrypt with key1, decrypt with key2 and encrypt with key3 again. -- As for ECB encryption but increases the key length to 168 bits. - There are theoretic attacks that can be used that make the effective - key length 112 bits, but this attack also requires 2^56 blocks of - memory, not very likely, even for the NSA. -- If both keys are the same it is equivalent to encrypting once with - just one key. -- If the first and last key are the same, the key length is 112 bits. - There are attacks that could reduce the key space to 55 bit's but it - requires 2^56 blocks of memory. -- If all 3 keys are the same, this is effectively the same as normal - ecb mode. - -Triple CBC Mode (des_ede3_cbc_encrypt()) -- Encrypt with key1, decrypt with key2 and then encrypt with key3. -- As for CBC encryption but increases the key length to 168 bits with - the same restrictions as for triple ecb mode. - -==== digest.doc ======================================================== - - -The Message Digest subroutines. - -These routines require "evp.h" to be included. - -These functions are a higher level interface to the various message digest -routines found in this library. As such, they allow the same code to be -used to digest via different algorithms with only a change in an initial -parameter. They are basically just a front-end to the MD2, MD5, SHA -and SHA1 -routines. - -These routines all take a pointer to the following structure to specify -which message digest algorithm to use. -typedef struct evp_md_st - { - int type; - int pkey_type; - int md_size; - void (*init)(); - void (*update)(); - void (*final)(); - - int required_pkey_type; /*EVP_PKEY_xxx */ - int (*sign)(); - int (*verify)(); - } EVP_MD; - -If additional message digest algorithms are to be supported, a structure of -this type needs to be declared and populated and then the Digest routines -can be used with that algorithm. The type field is the object NID of the -digest type (read the section on Objects for an explanation). The pkey_type -is the Object type to use when the a message digest is generated by there -routines and then is to be signed with the pkey algorithm. Md_size is -the size of the message digest returned. Init, update -and final are the relevant functions to perform the message digest function -by parts. One reason for specifying the message digest to use via this -mechanism is that if you only use md5, only the md5 routines will -be included in you linked program. If you passed an integer -that specified which message digest to use, the routine that mapped that -integer to a set of message digest functions would cause all the message -digests functions to be link into the code. This setup also allows new -message digest functions to be added by the application. - -The six message digests defined in this library are - -EVP_MD *EVP_md2(void); /* RSA sign/verify */ -EVP_MD *EVP_md5(void); /* RSA sign/verify */ -EVP_MD *EVP_sha(void); /* RSA sign/verify */ -EVP_MD *EVP_sha1(void); /* RSA sign/verify */ -EVP_MD *EVP_dss(void); /* DSA sign/verify */ -EVP_MD *EVP_dss1(void); /* DSA sign/verify */ - -All the message digest routines take a EVP_MD_CTX pointer as an argument. -The state of the message digest is kept in this structure. - -typedef struct pem_md_ctx_st - { - EVP_MD *digest; - union { - unsigned char base[4]; /* this is used in my library as a - * 'pointer' to all union elements - * structures. */ - MD2_CTX md2; - MD5_CTX md5; - SHA_CTX sha; - } md; - } EVP_MD_CTX; - -The Digest functions are as follows. - -void EVP_DigestInit( -EVP_MD_CTX *ctx, -EVP_MD *type); - This function is used to initialise the EVP_MD_CTX. The message - digest that will associated with 'ctx' is specified by 'type'. - -void EVP_DigestUpdate( -EVP_MD_CTX *ctx, -unsigned char *data, -unsigned int cnt); - This function is used to pass more data to the message digest - function. 'cnt' bytes are digested from 'data'. - -void EVP_DigestFinal( -EVP_MD_CTX *ctx, -unsigned char *md, -unsigned int *len); - This function finishes the digestion and puts the message digest - into 'md'. The length of the message digest is put into len; - EVP_MAX_MD_SIZE is the size of the largest message digest that - can be returned from this function. Len can be NULL if the - size of the digest is not required. - - -==== encode.doc ======================================================== - - -void EVP_EncodeInit(EVP_ENCODE_CTX *ctx); -void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out, - int *outl,unsigned char *in,int inl); -void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl); -int EVP_EncodeBlock(unsigned char *t, unsigned char *f, int n); - -void EVP_DecodeInit(EVP_ENCODE_CTX *ctx); -int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx,unsigned char *out,int *outl, - unsigned char *in, int inl); -int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned - char *out, int *outl); -int EVP_DecodeBlock(unsigned char *t, unsigned - char *f, int n); - - -==== envelope.doc ======================================================== - -The following routines are use to create 'digital' envelopes. -By this I mean that they perform various 'higher' level cryptographic -functions. Have a read of 'cipher.doc' and 'digest.doc' since those -routines are used by these functions. -cipher.doc contains documentation about the cipher part of the -envelope library and digest.doc contatins the description of the -message digests supported. - -To 'sign' a document involves generating a message digest and then encrypting -the digest with an private key. - -#define EVP_SignInit(a,b) EVP_DigestInit(a,b) -#define EVP_SignUpdate(a,b,c) EVP_DigestUpdate(a,b,c) -Due to the fact this operation is basically just an extended message -digest, the first 2 functions are macro calls to Digest generating -functions. - -int EVP_SignFinal( -EVP_MD_CTX *ctx, -unsigned char *md, -unsigned int *s, -EVP_PKEY *pkey); - This finalisation function finishes the generation of the message -digest and then encrypts the digest (with the correct message digest -object identifier) with the EVP_PKEY private key. 'ctx' is the message digest -context. 'md' will end up containing the encrypted message digest. This -array needs to be EVP_PKEY_size(pkey) bytes long. 's' will actually -contain the exact length. 'pkey' of course is the private key. It is -one of EVP_PKEY_RSA or EVP_PKEY_DSA type. -If there is an error, 0 is returned, otherwise 1. - -Verify is used to check an signed message digest. - -#define EVP_VerifyInit(a,b) EVP_DigestInit(a,b) -#define EVP_VerifyUpdate(a,b,c) EVP_DigestUpdate(a,b,c) -Since the first step is to generate a message digest, the first 2 functions -are macros. - -int EVP_VerifyFinal( -EVP_MD_CTX *ctx, -unsigned char *md, -unsigned int s, -EVP_PKEY *pkey); - This function finishes the generation of the message digest and then -compares it with the supplied encrypted message digest. 'md' contains the -'s' bytes of encrypted message digest. 'pkey' is used to public key decrypt -the digest. It is then compared with the message digest just generated. -If they match, 1 is returned else 0. - -int EVP_SealInit(EVP_CIPHER_CTX *ctx, EVP_CIPHER *type, unsigned char **ek, - int *ekl, unsigned char *iv, EVP_PKEY **pubk, int npubk); -Must have at least one public key, error is 0. I should also mention that -the buffers pointed to by 'ek' need to be EVP_PKEY_size(pubk[n]) is size. - -#define EVP_SealUpdate(a,b,c,d,e) EVP_EncryptUpdate(a,b,c,d,e) -void EVP_SealFinal(EVP_CIPHER_CTX *ctx,unsigned char *out,int *outl); - - -int EVP_OpenInit(EVP_CIPHER_CTX *ctx,EVP_CIPHER *type,unsigned char *ek, - int ekl,unsigned char *iv,EVP_PKEY *priv); -0 on failure - -#define EVP_OpenUpdate(a,b,c,d,e) EVP_DecryptUpdate(a,b,c,d,e) - -int EVP_OpenFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl); -Decrypt final return code - - -==== error.doc ======================================================== - -The error routines. - -The 'error' system I've implemented is intended to server 2 purpose, to -record the reason why a command failed and to record where in the libraries -the failure occurred. It is more or less setup to record a 'trace' of which -library components were being traversed when the error occurred. - -When an error is recorded, it is done so a as single unsigned long which is -composed of three parts. The top byte is the 'library' number, the middle -12 bytes is the function code, and the bottom 12 bits is the 'reason' code. - -Each 'library', or should a say, 'section' of the SSLeay library has a -different unique 'library' error number. Each function in the library has -a number that is unique for that library. Each 'library' also has a number -for each 'error reason' that is only unique for that 'library'. - -Due to the way these error routines record a 'error trace', there is an -array per thread that is used to store the error codes. -The various functions in this library are used to access -and manipulate this array. - -void ERR_put_error(int lib, int func,int reason); - This routine records an error in library 'lib', function 'func' -and reason 'reason'. As errors get 'put' into the buffer, they wrap -around and overwrite old errors if too many are written. It is assumed -that the last errors are the most important. - -unsigned long ERR_get_error(void ); - This function returns the last error added to the error buffer. -In effect it is popping the value off the buffer so repeated calls will -continue to return values until there are no more errors to return in which -case 0 is returned. - -unsigned long ERR_peek_error(void ); - This function returns the value of the last error added to the -error buffer but does not 'pop' it from the buffer. - -void ERR_clear_error(void ); - This function clears the error buffer, discarding all unread -errors. - -While the above described error system obviously produces lots of different -error number, a method for 'reporting' these errors in a human readable -form is required. To achieve this, each library has the option of -'registering' error strings. - -typedef struct ERR_string_data_st - { - unsigned long error; - char *string; - } ERR_STRING_DATA; - -The 'ERR_STRING_DATA' contains an error code and the corresponding text -string. To add new function error strings for a library, the -ERR_STRING_DATA needs to be 'registered' with the library. - -void ERR_load_strings(unsigned long lib,ERR_STRING_DATA *err); - This function 'registers' the array of ERR_STRING_DATA pointed to by -'err' as error text strings for the error library 'lib'. - -void ERR_free_strings(void); - This function free()s all the loaded error strings. - -char *ERR_error_string(unsigned long error,char *buf); - This function returns a text string that is a human readable -version of the error represented by 'error'. Buff should be at least 120 -bytes long and if it is NULL, the return value is a pointer to a static -variable that will contain the error string, otherwise 'buf' is returned. -If there is not a text string registered for a particular error, a text -string containing the error number is returned instead. - -void ERR_print_errors(BIO *bp); -void ERR_print_errors_fp(FILE *fp); - This function is a convenience routine that prints the error string -for each error until all errors have been accounted for. - -char *ERR_lib_error_string(unsigned long e); -char *ERR_func_error_string(unsigned long e); -char *ERR_reason_error_string(unsigned long e); -The above three functions return the 3 different components strings for the -error 'e'. ERR_error_string() uses these functions. - -void ERR_load_ERR_strings(void ); - This function 'registers' the error strings for the 'ERR' module. - -void ERR_load_crypto_strings(void ); - This function 'register' the error strings for just about every -library in the SSLeay package except for the SSL routines. There is no -need to ever register any error text strings and you will probably save in -program size. If on the other hand you do 'register' all errors, it is -quite easy to determine why a particular routine failed. - -As a final footnote as to why the error system is designed as it is. -1) I did not want a single 'global' error code. -2) I wanted to know which subroutine a failure occurred in. -3) For Windows NT etc, it should be simple to replace the 'key' routines - with code to pass error codes back to the application. -4) I wanted the option of meaningful error text strings. - -Late breaking news - the changes to support threads. - -Each 'thread' has an 'ERR_STATE' state associated with it. -ERR_STATE *ERR_get_state(void ) will return the 'state' for the calling -thread/process. - -ERR_remove_state(unsigned long pid); will 'free()' this state. If pid == 0 -the current 'thread/process' will have it's error state removed. -If you do not remove the error state of a thread, this could be considered a -form of memory leak, so just after 'reaping' a thread that has died, -call ERR_remove_state(pid). - -Have a read of thread.doc for more details for what is required for -multi-threading support. All the other error routines will -work correctly when using threads. - - -==== idea.doc ======================================================== - -The IDEA library. -IDEA is a block cipher that operates on 64bit (8 byte) quantities. It -uses a 128bit (16 byte) key. It can be used in all the modes that DES can -be used. This library implements the ecb, cbc, cfb64 and ofb64 modes. - -For all calls that have an 'input' and 'output' variables, they can be the -same. - -This library requires the inclusion of 'idea.h'. - -All of the encryption functions take what is called an IDEA_KEY_SCHEDULE as an -argument. An IDEA_KEY_SCHEDULE is an expanded form of the idea key. -For all modes of the IDEA algorithm, the IDEA_KEY_SCHEDULE used for -decryption is different to the one used for encryption. - -The define IDEA_ENCRYPT is passed to specify encryption for the functions -that require an encryption/decryption flag. IDEA_DECRYPT is passed to -specify decryption. For some mode there is no encryption/decryption -flag since this is determined by the IDEA_KEY_SCHEDULE. - -So to encrypt you would do the following -idea_set_encrypt_key(key,encrypt_ks); -idea_ecb_encrypt(...,encrypt_ks); -idea_cbc_encrypt(....,encrypt_ks,...,IDEA_ENCRYPT); - -To Decrypt -idea_set_encrypt_key(key,encrypt_ks); -idea_set_decrypt_key(encrypt_ks,decrypt_ks); -idea_ecb_encrypt(...,decrypt_ks); -idea_cbc_encrypt(....,decrypt_ks,...,IDEA_DECRYPT); - -Please note that any of the encryption modes specified in my DES library -could be used with IDEA. I have only implemented ecb, cbc, cfb64 and -ofb64 for the following reasons. -- ecb is the basic IDEA encryption. -- cbc is the normal 'chaining' form for block ciphers. -- cfb64 can be used to encrypt single characters, therefore input and output - do not need to be a multiple of 8. -- ofb64 is similar to cfb64 but is more like a stream cipher, not as - secure (not cipher feedback) but it does not have an encrypt/decrypt mode. -- If you want triple IDEA, thats 384 bits of key and you must be totally - obsessed with security. Still, if you want it, it is simple enough to - copy the function from the DES library and change the des_encrypt to - idea_encrypt; an exercise left for the paranoid reader :-). - -The functions are as follows: - -void idea_set_encrypt_key( -unsigned char *key; -IDEA_KEY_SCHEDULE *ks); - idea_set_encrypt_key converts a 16 byte IDEA key into an - IDEA_KEY_SCHEDULE. The IDEA_KEY_SCHEDULE is an expanded form of - the key which can be used to perform IDEA encryption. - An IDEA_KEY_SCHEDULE is an expanded form of the key which is used to - perform actual encryption. It can be regenerated from the IDEA key - so it only needs to be kept when encryption is about - to occur. Don't save or pass around IDEA_KEY_SCHEDULE's since they - are CPU architecture dependent, IDEA keys are not. - -void idea_set_decrypt_key( -IDEA_KEY_SCHEDULE *encrypt_ks, -IDEA_KEY_SCHEDULE *decrypt_ks); - This functions converts an encryption IDEA_KEY_SCHEDULE into a - decryption IDEA_KEY_SCHEDULE. For all decryption, this conversion - of the key must be done. In some modes of IDEA, an - encryption/decryption flag is also required, this is because these - functions involve block chaining and the way this is done changes - depending on which of encryption of decryption is being done. - Please note that there is no quick way to generate the decryption - key schedule other than generating the encryption key schedule and - then converting it. - -void idea_encrypt( -unsigned long *data, -IDEA_KEY_SCHEDULE *ks); - This is the IDEA encryption function that gets called by just about - every other IDEA routine in the library. You should not use this - function except to implement 'modes' of IDEA. I say this because the - functions that call this routine do the conversion from 'char *' to - long, and this needs to be done to make sure 'non-aligned' memory - access do not occur. - Data is a pointer to 2 unsigned long's and ks is the - IDEA_KEY_SCHEDULE to use. Encryption or decryption depends on the - IDEA_KEY_SCHEDULE. - -void idea_ecb_encrypt( -unsigned char *input, -unsigned char *output, -IDEA_KEY_SCHEDULE *ks); - This is the basic Electronic Code Book form of IDEA (in DES this - mode is called Electronic Code Book so I'm going to use the term - for idea as well :-). - Input is encrypted into output using the key represented by - ks. Depending on the IDEA_KEY_SCHEDULE, encryption or - decryption occurs. Input is 8 bytes long and output is 8 bytes. - -void idea_cbc_encrypt( -unsigned char *input, -unsigned char *output, -long length, -IDEA_KEY_SCHEDULE *ks, -unsigned char *ivec, -int enc); - This routine implements IDEA in Cipher Block Chaining mode. - Input, which should be a multiple of 8 bytes is encrypted - (or decrypted) to output which will also be a multiple of 8 bytes. - The number of bytes is in length (and from what I've said above, - should be a multiple of 8). If length is not a multiple of 8, bad - things will probably happen. ivec is the initialisation vector. - This function updates iv after each call so that it can be passed to - the next call to idea_cbc_encrypt(). - -void idea_cfb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks, -des_cblock *ivec, -int *num, -int enc); - This is one of the more useful functions in this IDEA library, it - implements CFB mode of IDEA with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - Enc is used to indicate encryption or decryption. - One very important thing to remember is that when decrypting, use - the encryption form of the key. - CFB64 mode operates by using the cipher to - generate a stream of bytes which is used to encrypt the plain text. - The cipher text is then encrypted to generate the next 64 bits to - be xored (incrementally) with the next 64 bits of plain - text. As can be seen from this, to encrypt or decrypt, - the same 'cipher stream' needs to be generated but the way the next - block of data is gathered for encryption is different for - encryption and decryption. What this means is that to encrypt - idea_set_encrypt_key(key,ks); - idea_cfb64_encrypt(...,ks,..,IDEA_ENCRYPT) - do decrypt - idea_set_encrypt_key(key,ks) - idea_cfb64_encrypt(...,ks,...,IDEA_DECRYPT) - Note: The same IDEA_KEY_SCHEDULE but different encryption flags. - For idea_cbc or idea_ecb, idea_set_decrypt_key() would need to be - used to generate the IDEA_KEY_SCHEDULE for decryption. - The reason I'm stressing this point is that I just wasted 3 hours - today trying to decrypt using this mode and the decryption form of - the key :-(. - -void idea_ofb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -des_key_schedule ks, -des_cblock *ivec, -int *num); - This functions implements OFB mode of IDEA with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - This is in effect a stream cipher, there is no encryption or - decryption mode. The same key and iv should be used to - encrypt and decrypt. - -For reading passwords, I suggest using des_read_pw_string() from my DES library. -To generate a password from a text string, I suggest using MD5 (or MD2) to -produce a 16 byte message digest that can then be passed directly to -idea_set_encrypt_key(). - -===== -For more information about the specific IDEA modes in this library -(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the -documentation on my DES library. What is said about DES is directly -applicable for IDEA. - - -==== legal.doc ======================================================== - -From eay@mincom.com Thu Jun 27 00:25:45 1996 -Received: by orb.mincom.oz.au id AA15821 - (5.65c/IDA-1.4.4 for eay); Wed, 26 Jun 1996 14:25:45 +1000 -Date: Wed, 26 Jun 1996 14:25:45 +1000 (EST) -From: Eric Young <eay@mincom.oz.au> -X-Sender: eay@orb -To: Ken Toll <ktoll@ren.digitalage.com> -Cc: Eric Young <eay@mincom.oz.au>, ssl-talk@netscape.com -Subject: Re: Unidentified subject! -In-Reply-To: <9606261950.ZM28943@ren.digitalage.com> -Message-Id: <Pine.SOL.3.91.960626131156.28573K-100000@orb> -Mime-Version: 1.0 -Content-Type: TEXT/PLAIN; charset=US-ASCII -Status: O -X-Status: - - -This is a little off topic but since SSLeay is a free implementation of -the SSLv2 protocol, I feel it is worth responding on the topic of if it -is actually legal for Americans to use free cryptographic software. - -On Wed, 26 Jun 1996, Ken Toll wrote: -> Is the U.S the only country that SSLeay cannot be used commercially -> (because of RSAref) or is that going to be an issue with every country -> that a client/server application (non-web browser/server) is deployed -> and sold? - ->From what I understand, the software patents that apply to algorithms -like RSA and DH only apply in the USA. The IDEA algorithm I believe is -patened in europe (USA?), but considing how little it is used by other SSL -implementations, it quite easily be left out of the SSLeay build -(this can be done with a compile flag). - -Actually if the RSA patent did apply outside the USA, it could be rather -interesting since RSA is not alowed to let RSA toolkits outside of the USA -[1], and since these are the only forms that they will alow the algorithm -to be used in, it would mean that non-one outside of the USA could produce -public key software which would be a very strong statment for -international patent law to make :-). This logic is a little flawed but -it still points out some of the more interesting permutations of USA -patent law and ITAR restrictions. - -Inside the USA there is also the unresolved issue of RC4/RC2 which were -made public on sci.crypt in Sep 1994 (RC4) and Feb 1996 (RC2). I have -copies of the origional postings if people are interested. RSA I believe -claim that they were 'trade-secrets' and that some-one broke an NDA in -revealing them. Other claim they reverse engineered the algorithms from -compiled binaries. If the algorithms were reverse engineered, I believe -RSA had no legal leg to stand on. If an NDA was broken, I don't know. -Regardless, RSA, I believe, is willing to go to court over the issue so -licencing is probably the best idea, or at least talk to them. -If there are people who actually know more about this, pease let me know, I -don't want to vilify or spread miss-information if I can help it. - -If you are not producing a web browser, it is easy to build SSLeay with -RC2/RC4 removed. Since RC4 is the defacto standard cipher in -all web software (and it is damn fast) it is more or less required for -www use. For non www use of SSL, especially for an application where -interoperability with other vendors is not critical just leave it out. - -Removing IDEA, RC2 and RC4 would only leave DES and Triple DES but -they should be ok. Considing that Triple DES can encrypt at rates of -410k/sec on a pentium 100, and 940k/sec on a P6/200, this is quite -reasonable performance. Single DES clocks in at 1160k/s and 2467k/s -respectivly is actually quite fast for those not so paranoid (56 bit key).[1] - -> Is it possible to get a certificate for commercial use outside of the U.S.? -yes. - -Thawte Consulting issues certificates (they are the people who sell the - Sioux httpd server and are based in South Africa) -Verisign will issue certificates for Sioux (sold from South Africa), so this - proves that they will issue certificate for OS use if they are - happy with the quality of the software. - -(The above mentioned companies just the ones that I know for sure are issuing - certificates outside the USA). - -There is always the point that if you are using SSL for an intra net, -SSLeay provides programs that can be used so you can issue your own -certificates. They need polishing but at least it is a good starting point. - -I am not doing anything outside Australian law by implementing these -algorithms (to the best of my knowedge). It is another example of how -the world legal system does not cope with the internet very well. - -I may start making shared libraries available (I have now got DLL's for -Windows). This will mean that distributions into the usa could be -shipped with a version with a reduced cipher set and the versions outside -could use the DLL/shared library with all the ciphers (and without RSAref). - -This could be completly hidden from the application, so this would not -even require a re-linking. - -This is the reverse of what people were talking about doing to get around -USA export regulations :-) - -eric - -[1]: The RSAref2.0 tookit is available on at least 3 ftp sites in Europe - and one in South Africa. - -[2]: Since I always get questions when I post benchmark numbers :-), - DES performace figures are in 1000's of bytes per second in cbc - mode using an 8192 byte buffer. The pentium 100 was running Windows NT - 3.51 DLLs and the 686/200 was running NextStep. - I quote pentium 100 benchmarks because it is basically the - 'entry level' computer that most people buy for personal use. - Windows 95 is the OS shipping on those boxes, so I'll give - NT numbers (the same Win32 runtime environment). The 686 - numbers are present as an indication of where we will be in a - few years. --- -Eric Young | BOOL is tri-state according to Bill Gates. -AARNet: eay@mincom.oz.au | RTFM Win32 GetMessage(). - - - -==== lhash.doc ======================================================== - -The LHASH library. - -I wrote this library in 1991 and have since forgotten why I called it lhash. -It implements a hash table from an article I read at the -time from 'Communications of the ACM'. What makes this hash -table different is that as the table fills, the hash table is -increased (or decreased) in size via realloc(). -When a 'resize' is done, instead of all hashes being redistributed over -twice as many 'buckets', one bucket is split. So when an 'expand' is done, -there is only a minimal cost to redistribute some values. Subsequent -inserts will cause more single 'bucket' redistributions but there will -never be a sudden large cost due to redistributing all the 'buckets'. - -The state for a particular hash table is kept in the LHASH structure. -The LHASH structure also records statistics about most aspects of accessing -the hash table. This is mostly a legacy of my writing this library for -the reasons of implementing what looked like a nice algorithm rather than -for a particular software product. - -Internal stuff you probably don't want to know about. -The decision to increase or decrease the hash table size is made depending -on the 'load' of the hash table. The load is the number of items in the -hash table divided by the size of the hash table. The default values are -as follows. If (hash->up_load < load) => expand. -if (hash->down_load > load) => contract. The 'up_load' has a default value of -1 and 'down_load' has a default value of 2. These numbers can be modified -by the application by just playing with the 'up_load' and 'down_load' -variables. The 'load' is kept in a form which is multiplied by 256. So -hash->up_load=8*256; will cause a load of 8 to be set. - -If you are interested in performance the field to watch is -num_comp_calls. The hash library keeps track of the 'hash' value for -each item so when a lookup is done, the 'hashes' are compared, if -there is a match, then a full compare is done, and -hash->num_comp_calls is incremented. If num_comp_calls is not equal -to num_delete plus num_retrieve it means that your hash function is -generating hashes that are the same for different values. It is -probably worth changing your hash function if this is the case because -even if your hash table has 10 items in a 'bucked', it can be searched -with 10 'unsigned long' compares and 10 linked list traverses. This -will be much less expensive that 10 calls to you compare function. - -LHASH *lh_new( -unsigned long (*hash)(), -int (*cmp)()); - This function is used to create a new LHASH structure. It is passed - function pointers that are used to store and retrieve values passed - into the hash table. The 'hash' - function is a hashing function that will return a hashed value of - it's passed structure. 'cmp' is passed 2 parameters, it returns 0 - is they are equal, otherwise, non zero. - If there are any problems (usually malloc failures), NULL is - returned, otherwise a new LHASH structure is returned. The - hash value is normally truncated to a power of 2, so make sure - that your hash function returns well mixed low order bits. - -void lh_free( -LHASH *lh); - This function free()s a LHASH structure. If there is malloced - data in the hash table, it will not be freed. Consider using the - lh_doall function to deallocate any remaining entries in the hash - table. - -char *lh_insert( -LHASH *lh, -char *data); - This function inserts the data pointed to by data into the lh hash - table. If there is already and entry in the hash table entry, the - value being replaced is returned. A NULL is returned if the new - entry does not clash with an entry already in the table (the normal - case) or on a malloc() failure (perhaps I should change this....). - The 'char *data' is exactly what is passed to the hash and - comparison functions specified in lh_new(). - -char *lh_delete( -LHASH *lh, -char *data); - This routine deletes an entry from the hash table. The value being - deleted is returned. NULL is returned if there is no such value in - the hash table. - -char *lh_retrieve( -LHASH *lh, -char *data); - If 'data' is in the hash table it is returned, else NULL is - returned. The way these routines would normally be uses is that a - dummy structure would have key fields populated and then - ret=lh_retrieve(hash,&dummy);. Ret would now be a pointer to a fully - populated structure. - -void lh_doall( -LHASH *lh, -void (*func)(char *a)); - This function will, for every entry in the hash table, call function - 'func' with the data item as parameters. - This function can be quite useful when used as follows. - void cleanup(STUFF *a) - { STUFF_free(a); } - lh_doall(hash,cleanup); - lh_free(hash); - This can be used to free all the entries, lh_free() then - cleans up the 'buckets' that point to nothing. Be careful - when doing this. If you delete entries from the hash table, - in the call back function, the table may decrease in size, - moving item that you are - currently on down lower in the hash table. This could cause - some entries to be skipped. The best solution to this problem - is to set lh->down_load=0 before you start. This will stop - the hash table ever being decreased in size. - -void lh_doall_arg( -LHASH *lh; -void(*func)(char *a,char *arg)); -char *arg; - This function is the same as lh_doall except that the function - called will be passed 'arg' as the second argument. - -unsigned long lh_strhash( -char *c); - This function is a demo string hashing function. Since the LHASH - routines would normally be passed structures, this routine would - not normally be passed to lh_new(), rather it would be used in the - function passed to lh_new(). - -The next three routines print out various statistics about the state of the -passed hash table. These numbers are all kept in the lhash structure. - -void lh_stats( -LHASH *lh, -FILE *out); - This function prints out statistics on the size of the hash table, - how many entries are in it, and the number and result of calls to - the routines in this library. - -void lh_node_stats( -LHASH *lh, -FILE *out); - For each 'bucket' in the hash table, the number of entries is - printed. - -void lh_node_usage_stats( -LHASH *lh, -FILE *out); - This function prints out a short summary of the state of the hash - table. It prints what I call the 'load' and the 'actual load'. - The load is the average number of data items per 'bucket' in the - hash table. The 'actual load' is the average number of items per - 'bucket', but only for buckets which contain entries. So the - 'actual load' is the average number of searches that will need to - find an item in the hash table, while the 'load' is the average number - that will be done to record a miss. - -==== md2.doc ======================================================== - -The MD2 library. -MD2 is a message digest algorithm that can be used to condense an arbitrary -length message down to a 16 byte hash. The functions all need to be passed -a MD2_CTX which is used to hold the MD2 context during multiple MD2_Update() -function calls. The normal method of use for this library is as follows - -MD2_Init(...); -MD2_Update(...); -... -MD2_Update(...); -MD2_Final(...); - -This library requires the inclusion of 'md2.h'. - -The main negative about MD2 is that it is slow, especially when compared -to MD5. - -The functions are as follows: - -void MD2_Init( -MD2_CTX *c); - This function needs to be called to initiate a MD2_CTX structure for - use. - -void MD2_Update( -MD2_CTX *c; -unsigned char *data; -unsigned long len); - This updates the message digest context being generated with 'len' - bytes from the 'data' pointer. The number of bytes can be any - length. - -void MD2_Final( -unsigned char *md; -MD2_CTX *c; - This function is called when a message digest of the data digested - with MD2_Update() is wanted. The message digest is put in the 'md' - array and is MD2_DIGEST_LENGTH (16) bytes long. - -unsigned char *MD2( -unsigned long n; -unsigned char *d; -unsigned char *md; - This function performs a MD2_Init(), followed by a MD2_Update() - followed by a MD2_Final() (using a local MD2_CTX). - The resulting digest is put into 'md' if it is not NULL. - Regardless of the value of 'md', the message - digest is returned from the function. If 'md' was NULL, the message - digest returned is being stored in a static structure. - -==== md5.doc ======================================================== - -The MD5 library. -MD5 is a message digest algorithm that can be used to condense an arbitrary -length message down to a 16 byte hash. The functions all need to be passed -a MD5_CTX which is used to hold the MD5 context during multiple MD5_Update() -function calls. This library also contains random number routines that are -based on MD5 - -The normal method of use for this library is as follows - -MD5_Init(...); -MD5_Update(...); -... -MD5_Update(...); -MD5_Final(...); - -This library requires the inclusion of 'md5.h'. - -The functions are as follows: - -void MD5_Init( -MD5_CTX *c); - This function needs to be called to initiate a MD5_CTX structure for - use. - -void MD5_Update( -MD5_CTX *c; -unsigned char *data; -unsigned long len); - This updates the message digest context being generated with 'len' - bytes from the 'data' pointer. The number of bytes can be any - length. - -void MD5_Final( -unsigned char *md; -MD5_CTX *c; - This function is called when a message digest of the data digested - with MD5_Update() is wanted. The message digest is put in the 'md' - array and is MD5_DIGEST_LENGTH (16) bytes long. - -unsigned char *MD5( -unsigned char *d; -unsigned long n; -unsigned char *md; - This function performs a MD5_Init(), followed by a MD5_Update() - followed by a MD5_Final() (using a local MD5_CTX). - The resulting digest is put into 'md' if it is not NULL. - Regardless of the value of 'md', the message - digest is returned from the function. If 'md' was NULL, the message - digest returned is being stored in a static structure. - - -==== memory.doc ======================================================== - -In the interests of debugging SSLeay, there is an option to compile -using some simple memory leak checking. - -All malloc(), free() and realloc() calls in SSLeay now go via -Malloc(), Free() and Realloc() (except those in crypto/lhash). - -If CRYPTO_MDEBUG is defined, these calls are #defined to -CRYPTO_malloc(), CRYPTO_free() and CRYPTO_realloc(). -If it is not defined, they are #defined to malloc(), free() and realloc(). - -the CRYPTO_malloc() routines by default just call the underlying library -functons. - -If CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_ON) is called, memory leak detection is -turned on. CRYPTO_mem_ctrl(CRYPTO_MEM_CHECK_OFF) turns it off. - -When turned on, each Malloc() or Realloc() call is recored along with the file -and line number from where the call was made. (This is done using the -lhash library which always uses normal system malloc(3) routines). - -void CRYPTO_mem_leaks(BIO *b); -void CRYPTO_mem_leaks_fp(FILE *fp); -These both print out the list of memory that has not been free()ed. -This will probably be rather hard to read, but if you look for the 'top level' -structure allocation, this will often give an idea as to what is not being -free()ed. I don't expect people to use this stuff normally. - -==== ca.1 ======================================================== - -From eay@orb.mincom.oz.au Thu Dec 28 23:56:45 1995 -Received: by orb.mincom.oz.au id AA07374 - (5.65c/IDA-1.4.4 for eay); Thu, 28 Dec 1995 13:56:45 +1000 -Date: Thu, 28 Dec 1995 13:56:45 +1000 (EST) -From: Eric Young <eay@mincom.oz.au> -X-Sender: eay@orb -To: sameer <sameer@c2.org> -Cc: ssleay@mincom.oz.au -Subject: Re: 'ca' -In-Reply-To: <199512230440.UAA23410@infinity.c2.org> -Message-Id: <Pine.SOL.3.91.951228133525.7269A-100000@orb> -Mime-Version: 1.0 -Content-Type: TEXT/PLAIN; charset=US-ASCII -Status: RO -X-Status: - -On Fri, 22 Dec 1995, sameer wrote: -> I could use documentation on 'ca'. Thanks. - -Very quickly. -The ca program uses the ssleay.conf file for most of its configuration - -./ca -help - - -verbose - Talk alot while doing things - -config file - A config file. If you don't want to use the - default config file - -name arg - The particular CA definition to use - In the config file, the section to use for parameters. This lets - multiple setups to be contained in the one file. By default, the - default_ca variable is looked up in the [ ca ] section. So in the - shipped ssleay.conf, the CA definition used is CA_default. It could be - any other name. - -gencrl days - Generate a new CRL, days is when the next CRL is due - This will generate a new certificate revocion list. - -days arg - number of days to certify the certificate for - When certifiying certificates, this is the number of days to use. - -md arg - md to use, one of md2, md5, sha or sha1 - -policy arg - The CA 'policy' to support - I'll describe this later, but there are 2 policies definied in the - shipped ssleay.conf - -keyfile arg - PEM RSA private key file - -key arg - key to decode the RSA private key if it is encrypted - since we need to keep the CA's RSA key encrypted - -cert - The CA certificate - -in file - The input PEM encoded certificate request(s) - -out file - Where to put the output file(s) - -outdir dir - Where to put output certificates - The -out options concatinates all the output certificied - certificates to one file, -outdir puts them in a directory, - named by serial number. - -infiles .... - The last argument, requests to process - The certificate requests to process, -in is the same. - -Just about all the above have default values defined in ssleay.conf. - -The key variables in ssleay.conf are (for the pariticular '-name' being -used, in the default, it is CA_default). - -dir is where all the CA database stuff is kept. -certs is where all the previously issued certificates are kept. -The database is a simple text database containing the following tab separated -fields. -status: a value of 'R' - revoked, 'E' -expired or 'V' valid. -issued date: When the certificate was certified. -revoked date: When it was revoked, blank if not revoked. -serial number: The certificate serial number. -certificate: Where the certificate is located. -CN: The name of the certificate. - -The demo file has quite a few made up values it it. The last 2 were -added by the ca program and are acurate. -The CA program does not update the 'certificate' file correctly right now. -The serial field should be unique as should the CN/status combination. -The ca program checks these at startup. What still needs to be -wrtten is a program to 'regenerate' the data base file from the issued -certificate list (and a CRL list). - -Back to the CA_default variables. - -Most of the variables are commented. - -policy is the default policy. - -Ok for policies, they define the order and which fields must be present -in the certificate request and what gets filled in. - -So a value of -countryName = match -means that the country name must match the CA certificate. -organizationalUnitName = optional -The org.Unit,Name does not have to be present and -commonName = supplied -commonName must be supplied in the certificate request. - -For the 'policy_match' polocy, the order of the attributes in the -generated certiticate would be -countryName -stateOrProvinceName -organizationName -organizationalUnitName -commonName -emailAddress - -Have a play, it sort of makes sense. If you think about how the persona -requests operate, it is similar to the 'policy_match' policy and the -'policy_anything' is similar to what versign is doing. - -I hope this helps a bit. Some backend scripts are definitly needed to -update the database and to make certificate revocion easy. All -certificates issued should also be kept forever (or until they expire?) - -hope this helps -eric (who has to run off an buy some cheap knee pads for the caving in 4 -days time :-) - --- -Eric Young | Signature removed since it was generating -AARNet: eay@mincom.oz.au | more followups than the message contents :-) - - -==== ms3-ca.doc ======================================================== - -Date: Mon, 9 Jun 97 08:00:33 +0200 -From: Holger.Reif@PrakInf.TU-Ilmenau.DE (Holger Reif) -Subject: ms3-ca.doc -Organization: TU Ilmenau, Fak. IA, FG Telematik -Content-Length: 14575 -Status: RO -X-Status: - -Loading client certs into MSIE 3.01 -=================================== - -This document contains all the information necessary to successfully set up -some scripts to issue client certs to Microsoft Internet Explorer. It -includes the required knowledge about the model MSIE uses for client -certification and includes complete sample scripts ready to play with. The -scripts were tested against a modified ca program of SSLeay 0.6.6 and should -work with the regular ca program that comes with version 0.8.0. I haven't -tested against MSIE 4.0 - -You can use the information contained in this document in either way you -want. However if you feel it saved you a lot of time I ask you to be as fair -as to mention my name: Holger Reif <reif@prakinf.tu-ilmenau.de>. - -1.) The model used by MSIE --------------------------- - -The Internet Explorer doesn't come with a embedded engine for installing -client certs like Netscape's Navigator. It rather uses the CryptoAPI (CAPI) -defined by Microsoft. CAPI comes with WindowsNT 4.0 or is installed together -with Internet Explorer since 3.01. The advantage of this approach is a higher -flexibility because the certificates in the (per user) system open -certificate store may be used by other applications as well. The drawback -however is that you need to do a bit more work to get a client cert issued. - -CAPI defines functions which will handle basic cryptographic work, eg. -generating keys, encrypting some data, signing text or building a certificate -request. The procedure is as follows: A CAPI function generates you a key -pair and saves it into the certificate store. After that one builds a -Distinguished Name. Together with that key pair another CAPI function forms a -PKCS#10 request which you somehow need to submit to a CA. Finally the issued -cert is given to a yet another CAPI function which saves it into the -certificate store. - -The certificate store with the user's keys and certs is in the registry. You -will find it under HKEY_CURRENT_USER/Software/Microsoft/Cryptography/ (I -leave it to you as a little exercise to figure out what all the entries mean -;-). Note that the keys are protected only with the user's usual Windows -login password. - -2.) The practical usage ------------------------ - -Unfortunatly since CAPI is a system API you can't access its functions from -HTML code directly. For this purpose Microsoft provides a wrapper called -certenr3.dll. This DLL accesses the CAPI functions and provides an interface -usable from Visual Basic Script. One needs to install that library on the -computer which wants to have client cert. The easiest way is to load it as an -ActiveX control (certenr3.dll is properly authenticode signed by MS ;-). If -you have ever enrolled e cert request at a CA you will have installed it. - -At time of writing certenr3.dll is contained in -http://www.microsoft.com/workshop/prog/security/csa/certenr3.exe. It comes -with an README file which explains the available functions. It is labeled -beta but every CA seems to use it anyway. The license.txt allows you the -usage for your own purposes (as far as I understood) and a somehow limited -distribution. - -The two functions of main interest are GenerateKeyPair and AcceptCredentials. -For complete explanation of all possible parameters see the README file. Here -are only minimal required parameters and their values. - -GenerateKeyPair(sessionID, FASLE, szName, 0, "ClientAuth", TRUE, FALSE, 1) -- sessionID is a (locally to that computer) unique string to correlate the -generated key pair with a cert installed later. -- szName is the DN of the form "C=DE; S=Thueringen; L=Ilmenau; CN=Holger -Reif; 1.2.840.113549.1.9.1=reif@prakinf.tu-ilmenau.de". Note that S is the -abreviation for StateOrProvince. The recognized abreviation include CN, O, C, -OU, G, I, L, S, T. If the abreviation is unknown (eg. for PKCS#9 email addr) -you need to use the full object identifier. The starting point for searching -them could be crypto/objects.h since all OIDs know to SSLeay are listed -there. -- note: the possible ninth parameter which should give a default name to the -certificate storage location doesn't seem to work. Changes to the constant -values in the call above doesn't seem to make sense. You can't generate -PKCS#10 extensions with that function. - -The result of GenerateKeyPair is the base64 encoded PKCS#10 request. However -it has a little strange format that SSLeay doesn't accept. (BTW I feel the -decision of rejecting that format as standard conforming.) It looks like -follows: - 1st line with 76 chars - 2nd line with 76 chars - ... - (n-2)th line with 76 chars - (n-1)th line contains a multiple of 4 chars less then 76 (possible -empty) - (n)th line has zero or 4 chars (then with 1 or 2 equal signs - the - original text's lenght wasn'T a multiple of 3) - The line separator has two chars: 0x0d 0x0a - -AcceptCredentials(sessionID, credentials, 0, FALSE) -- sessionID needs to be the same as while generating the key pair -- credentials is the base64 encoded PKCS#7 object containing the cert. - -CRL's and CA certs are not required simply just the client cert. (It seems to -me that both are not even checked somehow.) The only format of the base64 -encoded object I succesfully used was all characters in a very long string -without line feeds or carriage returns. (Hey, it doesn't matter, only a -computer reads it!) - -The result should be S_OK. For error handling see the example that comes with -certenr3.dll. - -A note about ASN.1 character encodings. certenr3.dll seems to know only about -2 of them: UniversalString and PrintableString. First it is definitely wrong -for an email address which is IA5STRING (checked by ssleay's ca). Second -unfortunately MSIE (at least until version 3.02) can't handle UniversalString -correctly - they just blow up you cert store! Therefore ssleay's ca (starting -from version 0.8.0) tries to convert the encodings automatically to IA5STRING -or TeletexString. The beef is it will work only for the latin-1 (western) -charset. Microsoft still has to do abit of homework... - -3.) An example --------------- - -At least you need two steps: generating the key & request and then installing -the certificate. A real world CA would have some more steps involved, eg. -accepting some license. Note that both scripts shown below are just -experimental state without any warrenty! - -First how to generate a request. Note that we can't use a static page because -of the sessionID. I generate it from system time plus pid and hope it is -unique enough. Your are free to feed it through md5 to get more impressive -ID's ;-) Then the intended text is read in with sed which inserts the -sessionID. - ------BEGIN ms-enroll.cgi----- -#!/bin/sh -SESSION_ID=`date '+%y%m%d%H%M%S'`$$ -echo Content-type: text/html -echo -sed s/template_for_sessId/$SESSION_ID/ <<EOF -<HTML><HEAD> -<TITLE>Certificate Enrollment Test Page</TITLE> -</HEAD><BODY> - -<OBJECT - classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43" - codebase=certenr3.dll - id=certHelper - > -</OBJECT> - -<CENTER> -<H2>enrollment for a personal cert</H2> -<BR><HR WIDTH=50%><BR><P> -<FORM NAME="MSIE_Enrollment" ACTION="ms-gencert.cgi" ENCTYPE=x-www-form- -encoded METHOD=POST> -<TABLE> - <TR><TD>Country</TD><TD><INPUT NAME="Country" VALUE=""></TD></TR> - <TR><TD>State</TD><TD><INPUT NAME="StateOrProvince" VALUE=""></TD></TR> - <TR><TD>Location</TD><TD><INPUT NAME="Location" VALUE=""></TD></TR> - <TR><TD>Organization</TD><TD><INPUT NAME="Organization" -VALUE=""></TD></TR> - <TR><TD>Organizational Unit</TD> - <TD><INPUT NAME="OrganizationalUnit" VALUE=""></TD></TR> - <TR><TD>Name</TD><TD><INPUT NAME="CommonName" VALUE=""></TD></TR> - <TR><TD>eMail Address</TD> - <TD><INPUT NAME="EmailAddress" VALUE=""></TD></TR> - <TR><TD></TD> - <TD><INPUT TYPE="BUTTON" NAME="submit" VALUE="Beantragen"></TD></TR> -</TABLE> - <INPUT TYPE="hidden" NAME="SessionId" VALUE="template_for_sessId"> - <INPUT TYPE="hidden" NAME="Request" VALUE=""> -</FORM> -<BR><HR WIDTH=50%><BR><P> -</CENTER> - -<SCRIPT LANGUAGE=VBS> - Dim DN - - Sub Submit_OnClick - Dim TheForm - Set TheForm = Document.MSIE_Enrollment - sessionId = TheForm.SessionId.value - reqHardware = FALSE - C = TheForm.Country.value - SP = TheForm.StateOrProvince.value - L = TheForm.Location.value - O = TheForm.Organization.value - OU = TheForm.OrganizationalUnit.value - CN = TheForm.CommonName.value - Email = TheForm.EmailAddress.value - szPurpose = "ClientAuth" - doAcceptanceUINow = FALSE - doOnline = TRUE - - DN = "" - - Call Add_RDN("C", C) - Call Add_RDN("S", SP) - Call Add_RDN("L", L) - Call Add_RDN("O", O) - Call Add_RDN("OU", OU) - Call Add_RDN("CN", CN) - Call Add_RDN("1.2.840.113549.1.9.1", Email) - ' rsadsi - ' pkcs - ' pkcs9 - ' eMailAddress - On Error Resume Next - sz10 = certHelper.GenerateKeyPair(sessionId, _ - FALSE, DN, 0, ClientAuth, FASLE, TRUE, 1)_ - theError = Err.Number - On Error Goto 0 - if (sz10 = Empty OR theError <> 0) Then - sz = "The error '" & Hex(theError) & "' occurred." & chr(13) & _ - chr(10) & "Your credentials could not be generated." - result = MsgBox(sz, 0, "Credentials Enrollment") - Exit Sub - else - TheForm.Request.value = sz10 - TheForm.Submit - end if - End Sub - - Sub Add_RDN(sn, value) - if (value <> "") then - if (DN <> "") then - DN = DN & "; " - end if - DN = DN & sn & "=" & value - end if - End Sub -</SCRIPT> -</BODY> -</HTML> -EOF ------END ms-enroll.cgi----- - -Second, how to extract the request and feed the certificate back? We need to -"normalize" the base64 encoding of the PKCS#10 format which means -regenerating the lines and wrapping with BEGIN and END line. This is done by -gawk. The request is taken by ca the normal way. Then the cert needs to be -packed into a PKCS#7 structure (note: the use of a CRL is necessary for -crl2pkcs7 as of version 0.6.6. Starting with 0.8.0 it it might probably be -ommited). Finally we need to format the PKCS#7 object and generate the HTML -text. I use two templates to have a clearer script. - -1st note: postit2 is slightly modified from a program I found at ncsa's ftp -site. Grab it from http://www.easterngraphics.com/certs/IX9704/postit2.c. You -need utils.c from there too. - -2nd note: I'm note quite sure wether the gawk script really handles all -possible inputs for the request right! Today I don't use this construction -anymore myself. - -3d note: the cert must be of version 3! This could be done with the nsComment -line in ssleay.cnf... - -------BEGIN ms-gencert.cgi----- -#!/bin/sh -FILE="/tmp/"`date '+%y%m%d%H%M%S'-`$$ -rm -f "$FILE".* - -HOME=`pwd`; export HOME # as ssleay.cnf insists on having such an env var -cd /usr/local/ssl #where demoCA (as named in ssleay.conf) is located - -postit2 -s " " -i 0x0d > "$FILE".inp # process the FORM vars - -SESSION_ID=`gawk '$1 == "SessionId" { print $2; exit }' "$FILE".inp` - -gawk \ - 'BEGIN { \ - OFS = ""; \ - print "-----BEGIN CERTIFICATE REQUEST-----"; \ - req_seen=0 \ - } \ - $1 == "Request" { \ - req_seen=1; \ - if (length($2) == 72) print($2); \ - lastline=$2; \ - next; \ - } \ - { \ - if (req_seen == 1) { \ - if (length($1) >= 72) print($1); \ - else if (length(lastline) < 72) { \ - req_seen=0; \ - print (lastline,$1); \ - } \ - lastline=$1; \ - } \ - } \ - END { \ - print "-----END CERTIFICATE REQUEST-----"; \ - }' > "$FILE".pem < "$FILE".inp - -ssleay ca -batch -in "$FILE".pem -key passwd -out "$FILE".out -ssleay crl2pkcs7 -certfile "$FILE".out -out "$FILE".pkcs7 -in demoCA/crl.pem - -sed s/template_for_sessId/$SESSION_ID/ <ms-enroll2a.html >"$FILE".cert -/usr/local/bin/gawk \ - 'BEGIN { \ - OFS = ""; \ - dq = sprintf("%c",34); \ - } \ - $0 ~ "PKCS7" { next; } \ - { \ - print dq$0dq" & _"; \ - }' <"$FILE".pkcs7 >> "$FILE".cert -cat ms-enroll2b.html >>"$FILE".cert - -echo Content-type: text/html -echo Content-length: `wc -c "$FILE".cert` -echo -cat "$FILE".cert -rm -f "$FILE".* ------END ms-gencert.cgi----- - -----BEGIN ms-enroll2a.html---- -<HTML><HEAD><TITLE>Certificate Acceptance Test Page</TITLE></HEAD><BODY> - -<OBJECT - classid="clsid:33BEC9E0-F78F-11cf-B782-00C04FD7BF43" - codebase=certenr3.dll - id=certHelper - > -</OBJECT> - -<CENTER> -<H2>Your personal certificate</H2> -<BR><HR WIDTH=50%><BR><P> -Press the button! -<P><INPUT TYPE=BUTTON VALUE="Nimm mich!" NAME="InstallCert"> -</CENTER> -<BR><HR WIDTH=50%><BR> - -<SCRIPT LANGUAGE=VBS> - Sub InstallCert_OnClick - - sessionId = "template_for_sessId" -credentials = "" & _ -----END ms-enroll2a.html---- - -----BEGIN ms-enroll2b.html---- -"" - On Error Resume Next - result = certHelper.AcceptCredentials(sessionId, credentials, 0, -FALSE) - if (IsEmpty(result)) Then - sz = "The error '" & Err.Number & "' occurred." & chr(13) & -chr(10) & "This Digital ID could not be registered." - msgOut = MsgBox(sz, 0, "Credentials Registration Error") - navigate "error.html" - else - sz = "Digital ID successfully registered." - msgOut = MsgBox(sz, 0, "Credentials Registration") - navigate "success.html" - end if - Exit Sub - End Sub -</SCRIPT> -</BODY> -</HTML> -----END ms-enroll2b.html---- - -4.) What do do with the cert? ------------------------------ - -The cert is visible (without restarting MSIE) under the following menu: -View->Options->Security->Personal certs. You can examine it's contents at -least partially. - -To use it for client authentication you need to use SSL3.0 (fortunately -SSLeay supports it with 0.8.0). Furthermore MSIE is told to only supports a -kind of automatic selection of certs (I personally wasn't able to test it -myself). But there is a requirement that the issuer of the server cert and -the issuer of the client cert needs to be the same (according to a developer -from MS). Which means: you need may more then one cert to talk to all -servers... - -I'm sure we will get a bit more experience after ApacheSSL is available for -SSLeay 0.8.8. - - -I hope you enjoyed reading and that in future questions on this topic will -rarely appear on ssl-users@moncom.com ;-) - -Ilmenau, 9th of June 1997 -Holger Reif <reif@prakinf.tu-ilmenau.de> --- -read you later - Holger Reif ----------------------------------------- Signaturprojekt Deutsche Einheit -TU Ilmenau - Informatik - Telematik (Verdamp lang her) -Holger.Reif@PrakInf.TU-Ilmenau.DE Alt wie ein Baum werden, um ueber -http://Remus.PrakInf.TU-Ilmenau.DE/Reif/ alle 7 Bruecken gehen zu koennen - - -==== ns-ca.doc ======================================================== - -The following documentation was supplied by Jeff Barber, who provided the -patch to the CA program to add this functionality. - -eric --- -Jeff Barber Email: jeffb@issl.atl.hp.com - -Hewlett Packard Phone: (404) 648-9503 -Internet and System Security Lab Fax: (404) 648-9516 - - oo ----------------------cut /\ here for ns-ca.doc ------------------------------ - -This document briefly describes how to use SSLeay to implement a -certificate authority capable of dynamically serving up client -certificates for version 3.0 beta 5 (and presumably later) versions of -the Netscape Navigator. Before describing how this is done, it's -important to understand a little about how the browser implements its -client certificate support. This is documented in some detail in the -URLs based at <URL:http://home.netscape.com/eng/security/certs.html>. -Here's a brief overview: - -- The Navigator supports a new HTML tag "KEYGEN" which will cause - the browser to generate an RSA key pair when you submit a form - containing the tag. The public key, along with an optional - challenge (supposedly provided for use in certificate revocation - but I don't use it) is signed, DER-encoded, base-64 encoded - and sent to the web server as the value of the variable - whose NAME is provided in the KEYGEN tag. The private key is - stored by the browser in a local key database. - - This "Signed Public Key And Challenge" (SPKAC) arrives formatted - into 64 character lines (which are of course URL-encoded when - sent via HTTP -- i.e. spaces, newlines and most punctuatation are - encoded as "%HH" where HH is the hex equivalent of the ASCII code). - Note that the SPKAC does not contain the other usual attributes - of a certificate request, especially the subject name fields. - These must be otherwise encoded in the form for submission along - with the SPKAC. - -- Either immediately (in response to this form submission), or at - some later date (a real CA will probably verify your identity in - some way before issuing the certificate), a web server can send a - certificate based on the public key and other attributes back to - the browser by encoding it in DER (the binary form) and sending it - to the browser as MIME type: - "Content-type: application/x-x509-user-cert" - - The browser uses the public key encoded in the certificate to - associate the certificate with the appropriate private key in - its local key database. Now, the certificate is "installed". - -- When a server wants to require authentication based on client - certificates, it uses the right signals via the SSL protocol to - trigger the Navigator to ask you which certificate you want to - send. Whether the certificate is accepted is dependent on CA - certificates and so forth installed in the server and is beyond - the scope of this document. - - -Now, here's how the SSLeay package can be used to provide client -certficates: - -- You prepare a file for input to the SSLeay ca application. - The file contains a number of "name = value" pairs that identify - the subject. The names here are the same subject name component - identifiers used in the CA section of the lib/ssleay.conf file, - such as "emailAddress", "commonName" "organizationName" and so - forth. Both the long version and the short version (e.g. "Email", - "CN", "O") can be used. - - One more name is supported: this one is "SPKAC". Its value - is simply the value of the base-64 encoded SPKAC sent by the - browser (with all the newlines and other space charaters - removed -- and newline escapes are NOT supported). - - [ As of SSLeay 0.6.4, multiple lines are supported. - Put a \ at the end of each line and it will be joined with the - previous line with the '\n' removed - eay ] - - Here's a sample input file: - -C = US -SP = Georgia -O = Some Organization, Inc. -OU = Netscape Compatibility Group -CN = John X. Doe -Email = jxdoe@someorg.com -SPKAC = MIG0MGAwXDANBgkqhkiG9w0BAQEFAANLADBIAkEAwmk6FMJ4uAVIYbcvIOx5+bDGTfvL8X5gE+R67ccMk6rCSGbVQz2cetyQtnI+VIs0NwdD6wjuSuVtVFbLoHonowIDAQABFgAwDQYJKoZIhvcNAQEEBQADQQBFZDUWFl6BJdomtN1Bi53mwijy1rRgJ4YirF15yBEDM3DjAQkKXHYOIX+qpz4KXKnl6EYxTnGSFL5wWt8X2iyx - -- You execute the ca command (either from a CGI program run out of - the web server, or as a later manual task) giving it the above - file as input. For example, if the file were named /tmp/cert.req, - you'd run: - $SSLDIR/bin/ca -spkac /tmp/cert.req -out /tmp/cert - - The output is in DER format (binary) if a -out argument is - provided, as above; otherwise, it's in the PEM format (base-64 - encoded DER). Also, the "-batch" switch is implied by the - "-spkac" so you don't get asked whether to complete the signing - (probably it shouldn't work this way but I was only interested - in hacking together an online CA that could be used for issuing - test certificates). - - The "-spkac" capability doesn't support multiple files (I think). - - Any CHALLENGE provided in the SPKAC is simply ignored. - - The interactions between the identification fields you provide - and those identified in your lib/ssleay.conf are the same as if - you did an ordinary "ca -in infile -out outfile" -- that is, if - something is marked as required in the ssleay.conf file and it - isn't found in the -spkac file, the certificate won't be issued. - -- Now, you pick up the output from /tmp/cert and pass it back to - the Navigator prepending the Content-type string described earlier. - -- In order to run the ca command out of a CGI program, you must - provide a password to decrypt the CA's private key. You can - do this by using "echo MyKeyPassword | $SSLDIR/bin/ca ..." - I think there's a way to not encrypt the key file in the first - place, but I didn't see how to do that, so I made a small change - to the library that allows the password to be accepted from a pipe. - Either way is UTTERLY INSECURE and a real CA would never do that. - - [ You can use the 'ssleay rsa' command to remove the password - from the private key, or you can use the '-key' option to the - ca command to specify the decryption key on the command line - or use the -nodes option when generating the key. - ca will try to clear the command line version of the password - but for quite a few operating systems, this is not possible. - - eric ] - -So, what do you have to do to make use of this stuff to create an online -demo CA capability with SSLeay? - -1 Create an HTML form for your users. The form should contain - fields for all of the required or optional fields in ssleay.conf. - The form must contain a KEYGEN tag somewhere with at least a NAME - attribute. - -2 Create a CGI program to process the form input submitted by the - browser. The CGI program must URL-decode the variables and create - the file described above, containing subject identification info - as well as the SPKAC block. It should then run the the ca program - with the -spkac option. If it works (check the exit status), - return the new certificate with the appropriate MIME type. If not, - return the output of the ca command with MIME type "text/plain". - -3 Set up your web server to accept connections signed by your demo - CA. This probably involves obtaining the PEM-encoded CA certificate - (ordinarily in $SSLDIR/CA/cacert.pem) and installing it into a - server database. See your server manual for instructions. - - -==== obj.doc ======================================================== - -The Object library. - -As part of my Crypto library, I found I required a method of identifying various -objects. These objects normally had 3 different values associated with -them, a short text name, a long (or lower case) text name, and an -ASN.1 Object Identifier (which is a sequence of numbers). -This library contains a static list of objects and functions to lookup -according to one type and to return the other types. - -To use these routines, 'Object.h' needs to be included. - -For each supported object, #define entries are defined as follows -#define SN_Algorithm "Algorithm" -#define LN_algorithm "algorithm" -#define NID_algorithm 38 -#define OBJ_algorithm 1L,3L,14L,3L,2L - -SN_ stands for short name. -LN_ stands for either long name or lowercase name. -NID_ stands for Numeric ID. I each object has a unique NID and this - should be used internally to identify objects. -OBJ_ stands for ASN.1 Object Identifier or ASN1_OBJECT as defined in the - ASN1 routines. These values are used in ASN1 encoding. - -The following functions are to be used to return pointers into a static -definition of these types. What this means is "don't try to free() any -pointers returned from these functions. - -ASN1_OBJECT *OBJ_nid2obj( -int n); - Return the ASN1_OBJECT that corresponds to a NID of n. - -char *OBJ_nid2ln( -int n); - Return the long/lower case name of the object represented by the - NID of n. - -char *OBJ_nid2sn( -int n); - Return the short name for the object represented by the NID of n. - -ASN1_OBJECT *OBJ_dup( -ASN1_OBJECT *o); - Duplicate and return a new ASN1_OBJECT that is the same as the - passed parameter. - -int OBJ_obj2nid( -ASN1_OBJECT *o); - Given ASN1_OBJECT o, return the NID that corresponds. - -int OBJ_ln2nid( -char *s); - Given the long/lower case name 's', return the NID of the object. - -int OBJ_sn2nid( -char *s); - Given the short name 's', return the NID of the object. - -char *OBJ_bsearch( -char *key, -char *base, -int num, -int size, -int (*cmp)()); - Since I have come across a few platforms that do not have the - bsearch() function, OBJ_bsearch is my version of that function. - Feel free to use this function, but you may as well just use the - normal system bsearch(3) if it is present. This version also - has tolerance of being passed NULL pointers. - -==== keys =========================================================== - -EVP_PKEY_DSA -EVP_PKEY_DSA2 -EVP_PKEY_DSA3 -EVP_PKEY_DSA4 - -EVP_PKEY_RSA -EVP_PKEY_RSA2 - -valid DSA pkey types - NID_dsa - NID_dsaWithSHA - NID_dsaWithSHA1 - NID_dsaWithSHA1_2 - -valid RSA pkey types - NID_rsaEncryption - NID_rsa - -NID_dsaWithSHA NID_dsaWithSHA DSA SHA -NID_dsa NID_dsaWithSHA1 DSA SHA1 -NID_md2 NID_md2WithRSAEncryption RSA-pkcs1 MD2 -NID_md5 NID_md5WithRSAEncryption RSA-pkcs1 MD5 -NID_mdc2 NID_mdc2WithRSA RSA-none MDC2 -NID_ripemd160 NID_ripemd160WithRSA RSA-pkcs1 RIPEMD160 -NID_sha NID_shaWithRSAEncryption RSA-pkcs1 SHA -NID_sha1 NID_sha1WithRSAEncryption RSA-pkcs1 SHA1 - -==== rand.doc ======================================================== - -My Random number library. - -These routines can be used to generate pseudo random numbers and can be -used to 'seed' the pseudo random number generator (RNG). The RNG make no -effort to reproduce the same random number stream with each execution. -Various other routines in the SSLeay library 'seed' the RNG when suitable -'random' input data is available. Read the section at the end for details -on the design of the RNG. - -void RAND_bytes( -unsigned char *buf, -int num); - This routine puts 'num' random bytes into 'buf'. One should make - sure RAND_seed() has been called before using this routine. - -void RAND_seed( -unsigned char *buf, -int num); - This routine adds more 'seed' data the RNG state. 'num' bytes - are added to the RNG state, they are taken from 'buf'. This - routine can be called with sensitive data such as user entered - passwords. This sensitive data is in no way recoverable from - the RAND library routines or state. Try to pass as much data - from 'random' sources as possible into the RNG via this function. - Also strongly consider using the RAND_load_file() and - RAND_write_file() routines. - -void RAND_cleanup(); - When a program has finished with the RAND library, if it so - desires, it can 'zero' all RNG state. - -The following 3 routines are convenience routines that can be used to -'save' and 'restore' data from/to the RNG and it's state. -Since the more 'random' data that is feed as seed data the better, why not -keep it around between executions of the program? Of course the -application should pass more 'random' data in via RAND_seed() and -make sure no-one can read the 'random' data file. - -char *RAND_file_name( -char *buf, -int size); - This routine returns a 'default' name for the location of a 'rand' - file. The 'rand' file should keep a sequence of random bytes used - to initialise the RNG. The filename is put in 'buf'. Buf is 'size' - bytes long. Buf is returned if things go well, if they do not, - NULL is returned. The 'rand' file name is generated in the - following way. First, if there is a 'RANDFILE' environment - variable, it is returned. Second, if there is a 'HOME' environment - variable, $HOME/.rand is returned. Third, NULL is returned. NULL - is also returned if a buf would overflow. - -int RAND_load_file( -char *file, -long number); - This function 'adds' the 'file' into the RNG state. It does this by - doing a RAND_seed() on the value returned from a stat() system call - on the file and if 'number' is non-zero, upto 'number' bytes read - from the file. The number of bytes passed to RAND_seed() is returned. - -int RAND_write_file( -char *file), - RAND_write_file() writes N random bytes to the file 'file', where - N is the size of the internal RND state (currently 1k). - This is a suitable method of saving RNG state for reloading via - RAND_load_file(). - -What follows is a description of this RNG and a description of the rational -behind it's design. - -It should be noted that this RNG is intended to be used to generate -'random' keys for various ciphers including generation of DH and RSA keys. - -It should also be noted that I have just created a system that I am happy with. -It may be overkill but that does not worry me. I have not spent that much -time on this algorithm so if there are glaring errors, please let me know. -Speed has not been a consideration in the design of these routines. - -First up I will state the things I believe I need for a good RNG. -1) A good hashing algorithm to mix things up and to convert the RNG 'state' - to random numbers. -2) An initial source of random 'state'. -3) The state should be very large. If the RNG is being used to generate - 4096 bit RSA keys, 2 2048 bit random strings are required (at a minimum). - If your RNG state only has 128 bits, you are obviously limiting the - search space to 128 bits, not 2048. I'm probably getting a little - carried away on this last point but it does indicate that it may not be - a bad idea to keep quite a lot of RNG state. It should be easier to - break a cipher than guess the RNG seed data. -4) Any RNG seed data should influence all subsequent random numbers - generated. This implies that any random seed data entered will have - an influence on all subsequent random numbers generated. -5) When using data to seed the RNG state, the data used should not be - extractable from the RNG state. I believe this should be a - requirement because one possible source of 'secret' semi random - data would be a private key or a password. This data must - not be disclosed by either subsequent random numbers or a - 'core' dump left by a program crash. -6) Given the same initial 'state', 2 systems should deviate in their RNG state - (and hence the random numbers generated) over time if at all possible. -7) Given the random number output stream, it should not be possible to determine - the RNG state or the next random number. - - -The algorithm is as follows. - -There is global state made up of a 1023 byte buffer (the 'state'), a -working message digest ('md') and a counter ('count'). - -Whenever seed data is added, it is inserted into the 'state' as -follows. - The input is chopped up into units of 16 bytes (or less for - the last block). Each of these blocks is run through the MD5 - message digest. The data passed to the MD5 digest is the - current 'md', the same number of bytes from the 'state' - (the location determined by in incremented looping index) as - the current 'block' and the new key data 'block'. The result - of this is kept in 'md' and also xored into the 'state' at the - same locations that were used as input into the MD5. - I believe this system addresses points 1 (MD5), 3 (the 'state'), - 4 (via the 'md'), 5 (by the use of MD5 and xor). - -When bytes are extracted from the RNG, the following process is used. -For each group of 8 bytes (or less), we do the following, - Input into MD5, the top 8 bytes from 'md', the byte that are - to be overwritten by the random bytes and bytes from the - 'state' (incrementing looping index). From this digest output - (which is kept in 'md'), the top (upto) 8 bytes are - returned to the caller and the bottom (upto) 8 bytes are xored - into the 'state'. - Finally, after we have finished 'generation' random bytes for the - called, 'count' (which is incremented) and 'md' are fed into MD5 and - the results are kept in 'md'. - I believe the above addressed points 1 (use of MD5), 6 (by - hashing into the 'state' the 'old' data from the caller that - is about to be overwritten) and 7 (by not using the 8 bytes - given to the caller to update the 'state', but they are used - to update 'md'). - -So of the points raised, only 2 is not addressed, but sources of -random data will always be a problem. - - -==== rc2.doc ======================================================== - -The RC2 library. - -RC2 is a block cipher that operates on 64bit (8 byte) quantities. It -uses variable size key, but 128bit (16 byte) key would normally be considered -good. It can be used in all the modes that DES can be used. This -library implements the ecb, cbc, cfb64, ofb64 modes. - -I have implemented this library from an article posted to sci.crypt on -11-Feb-1996. I personally don't know how far to trust the RC2 cipher. -While it is capable of having a key of any size, not much reseach has -publically been done on it at this point in time (Apr-1996) -since the cipher has only been public for a few months :-) -It is of a similar speed to DES and IDEA, so unless it is required for -meeting some standard (SSLv2, perhaps S/MIME), it would probably be advisable -to stick to IDEA, or for the paranoid, Tripple DES. - -Mind you, having said all that, I should mention that I just read alot and -implement ciphers, I'm a 'babe in the woods' when it comes to evaluating -ciphers :-). - -For all calls that have an 'input' and 'output' variables, they can be the -same. - -This library requires the inclusion of 'rc2.h'. - -All of the encryption functions take what is called an RC2_KEY as an -argument. An RC2_KEY is an expanded form of the RC2 key. -For all modes of the RC2 algorithm, the RC2_KEY used for -decryption is the same one that was used for encryption. - -The define RC2_ENCRYPT is passed to specify encryption for the functions -that require an encryption/decryption flag. RC2_DECRYPT is passed to -specify decryption. - -Please note that any of the encryption modes specified in my DES library -could be used with RC2. I have only implemented ecb, cbc, cfb64 and -ofb64 for the following reasons. -- ecb is the basic RC2 encryption. -- cbc is the normal 'chaining' form for block ciphers. -- cfb64 can be used to encrypt single characters, therefore input and output - do not need to be a multiple of 8. -- ofb64 is similar to cfb64 but is more like a stream cipher, not as - secure (not cipher feedback) but it does not have an encrypt/decrypt mode. -- If you want triple RC2, thats 384 bits of key and you must be totally - obsessed with security. Still, if you want it, it is simple enough to - copy the function from the DES library and change the des_encrypt to - RC2_encrypt; an exercise left for the paranoid reader :-). - -The functions are as follows: - -void RC2_set_key( -RC2_KEY *ks; -int len; -unsigned char *key; -int bits; - RC2_set_key converts an 'len' byte key into a RC2_KEY. - A 'ks' is an expanded form of the 'key' which is used to - perform actual encryption. It can be regenerated from the RC2 key - so it only needs to be kept when encryption or decryption is about - to occur. Don't save or pass around RC2_KEY's since they - are CPU architecture dependent, 'key's are not. RC2 is an - interesting cipher in that it can be used with a variable length - key. 'len' is the length of 'key' to be used as the key. - A 'len' of 16 is recomended. The 'bits' argument is an - interesting addition which I only found out about in Aug 96. - BSAFE uses this parameter to 'limit' the number of bits used - for the key. To use the 'key' unmodified, set bits to 1024. - This is what old versions of my RC2 library did (SSLeay 0.6.3). - RSAs BSAFE library sets this parameter to be 128 if 128 bit - keys are being used. So to be compatable with BSAFE, set it - to 128, if you don't want to reduce RC2's key length, leave it - at 1024. - -void RC2_encrypt( -unsigned long *data, -RC2_KEY *key, -int encrypt); - This is the RC2 encryption function that gets called by just about - every other RC2 routine in the library. You should not use this - function except to implement 'modes' of RC2. I say this because the - functions that call this routine do the conversion from 'char *' to - long, and this needs to be done to make sure 'non-aligned' memory - access do not occur. - Data is a pointer to 2 unsigned long's and key is the - RC2_KEY to use. Encryption or decryption is indicated by 'encrypt'. - which can have the values RC2_ENCRYPT or RC2_DECRYPT. - -void RC2_ecb_encrypt( -unsigned char *in, -unsigned char *out, -RC2_KEY *key, -int encrypt); - This is the basic Electronic Code Book form of RC2 (in DES this - mode is called Electronic Code Book so I'm going to use the term - for rc2 as well. - Input is encrypted into output using the key represented by - key. Depending on the encrypt, encryption or - decryption occurs. Input is 8 bytes long and output is 8 bytes. - -void RC2_cbc_encrypt( -unsigned char *in, -unsigned char *out, -long length, -RC2_KEY *ks, -unsigned char *ivec, -int encrypt); - This routine implements RC2 in Cipher Block Chaining mode. - Input, which should be a multiple of 8 bytes is encrypted - (or decrypted) to output which will also be a multiple of 8 bytes. - The number of bytes is in length (and from what I've said above, - should be a multiple of 8). If length is not a multiple of 8, bad - things will probably happen. ivec is the initialisation vector. - This function updates iv after each call so that it can be passed to - the next call to RC2_cbc_encrypt(). - -void RC2_cfb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -RC2_KEY *schedule, -unsigned char *ivec, -int *num, -int encrypt); - This is one of the more useful functions in this RC2 library, it - implements CFB mode of RC2 with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - 'Encrypt' is used to indicate encryption or decryption. - CFB64 mode operates by using the cipher to generate a stream - of bytes which is used to encrypt the plain text. - The cipher text is then encrypted to generate the next 64 bits to - be xored (incrementally) with the next 64 bits of plain - text. As can be seen from this, to encrypt or decrypt, - the same 'cipher stream' needs to be generated but the way the next - block of data is gathered for encryption is different for - encryption and decryption. - -void RC2_ofb64_encrypt( -unsigned char *in, -unsigned char *out, -long length, -RC2_KEY *schedule, -unsigned char *ivec, -int *num); - This functions implements OFB mode of RC2 with 64bit feedback. - This allows you to encrypt an arbitrary number of bytes, - you do not require 8 byte padding. Each call to this - routine will encrypt the input bytes to output and then update ivec - and num. Num contains 'how far' we are though ivec. - This is in effect a stream cipher, there is no encryption or - decryption mode. - -For reading passwords, I suggest using des_read_pw_string() from my DES library. -To generate a password from a text string, I suggest using MD5 (or MD2) to -produce a 16 byte message digest that can then be passed directly to -RC2_set_key(). - -===== -For more information about the specific RC2 modes in this library -(ecb, cbc, cfb and ofb), read the section entitled 'Modes of DES' from the -documentation on my DES library. What is said about DES is directly -applicable for RC2. - - -==== rc4.doc ======================================================== - -The RC4 library. -RC4 is a stream cipher that operates on a byte stream. It can be used with -any length key but I would recommend normally using 16 bytes. - -This library requires the inclusion of 'rc4.h'. - -The RC4 encryption function takes what is called an RC4_KEY as an argument. -The RC4_KEY is generated by the RC4_set_key function from the key bytes. - -RC4, being a stream cipher, does not have an encryption or decryption mode. -It produces a stream of bytes that the input stream is xor'ed against and -so decryption is just a case of 'encrypting' again with the same key. - -I have only put in one 'mode' for RC4 which is the normal one. This means -there is no initialisation vector and there is no feedback of the cipher -text into the cipher. This implies that you should not ever use the -same key twice if you can help it. If you do, you leave yourself open to -known plain text attacks; if you know the plain text and -corresponding cipher text in one message, all messages that used the same -key can have the cipher text decoded for the corresponding positions in the -cipher stream. - -The main positive feature of RC4 is that it is a very fast cipher; about 4 -times faster that DES. This makes it ideally suited to protocols where the -key is randomly chosen, like SSL. - -The functions are as follows: - -void RC4_set_key( -RC4_KEY *key; -int len; -unsigned char *data); - This function initialises the RC4_KEY structure with the key passed - in 'data', which is 'len' bytes long. The key data can be any - length but 16 bytes seems to be a good number. - -void RC4( -RC4_KEY *key; -unsigned long len; -unsigned char *in; -unsigned char *out); - Do the actual RC4 encryption/decryption. Using the 'key', 'len' - bytes are transformed from 'in' to 'out'. As mentioned above, - decryption is the operation as encryption. - -==== ref.doc ======================================================== - -I have lots more references etc, and will update this list in the future, -30 Aug 1996 - eay - - -SSL The SSL Protocol - from Netscapes. - -RC4 Newsgroups: sci.crypt - From: sterndark@netcom.com (David Sterndark) - Subject: RC4 Algorithm revealed. - Message-ID: <sternCvKL4B.Hyy@netcom.com> - -RC2 Newsgroups: sci.crypt - From: pgut01@cs.auckland.ac.nz (Peter Gutmann) - Subject: Specification for Ron Rivests Cipher No.2 - Message-ID: <4fk39f$f70@net.auckland.ac.nz> - -MD2 RFC1319 The MD2 Message-Digest Algorithm -MD5 RFC1321 The MD5 Message-Digest Algorithm - -X509 Certificates - RFC1421 Privacy Enhancement for Internet Electronic Mail: Part I - RFC1422 Privacy Enhancement for Internet Electronic Mail: Part II - RFC1423 Privacy Enhancement for Internet Electronic Mail: Part III - RFC1424 Privacy Enhancement for Internet Electronic Mail: Part IV - -RSA and various standard encoding - PKCS#1 RSA Encryption Standard - PKCS#5 Password-Based Encryption Standard - PKCS#7 Cryptographic Message Syntax Standard - A Layman's Guide to a Subset of ASN.1, BER, and DER - An Overview of the PKCS Standards - Some Examples of the PKCS Standards - -IDEA Chapter 3 The Block Cipher IDEA - -RSA, prime number generation and bignum algorithms - Introduction To Algorithms, - Thomas Cormen, Charles Leiserson, Ronald Rivest, - Section 29 Arithmetic Circuits - Section 33 Number-Theoretic Algorithms - -Fast Private Key algorithm - Fast Decipherment Algorithm for RSA Public-Key Cryptosystem - J.-J. Quisquater and C. Couvreur, Electronics Letters, - 14th October 1982, Vol. 18 No. 21 - -Prime number generation and bignum algorithms. - PGP-2.3a - -==== rsa.doc ======================================================== - -The RSA encryption and utility routines. - -The RSA routines are built on top of a big number library (the BN library). -There are support routines in the X509 library for loading and manipulating -the various objects in the RSA library. When errors are returned, read -about the ERR library for how to access the error codes. - -All RSA encryption is done according to the PKCS-1 standard which is -compatible with PEM and RSAref. This means that any values being encrypted -must be less than the size of the modulus in bytes, minus 10, bytes long. - -This library uses RAND_bytes()() for it's random data, make sure to feed -RAND_seed() with lots of interesting and varied data before using these -routines. - -The RSA library has one specific data type, the RSA structure. -It is composed of 8 BIGNUM variables (see the BN library for details) and -can hold either a private RSA key or a public RSA key. -Some RSA libraries have different structures for public and private keys, I -don't. For my libraries, a public key is determined by the fact that the -RSA->d value is NULL. These routines will operate on any size RSA keys. -While I'm sure 4096 bit keys are very very secure, they take a lot longer -to process that 1024 bit keys :-). - -The function in the RSA library are as follows. - -RSA *RSA_new(); - This function creates a new RSA object. The sub-fields of the RSA - type are also malloced so you should always use this routine to - create RSA variables. - -void RSA_free( -RSA *rsa); - This function 'frees' an RSA structure. This routine should always - be used to free the RSA structure since it will also 'free' any - sub-fields of the RSA type that need freeing. - -int RSA_size( -RSA *rsa); - This function returns the size of the RSA modulus in bytes. Why do - I need this you may ask, well the reason is that when you encrypt - with RSA, the output string will be the size of the RSA modulus. - So the output for the RSA_encrypt and the input for the RSA_decrypt - routines need to be RSA_size() bytes long, because this is how many - bytes are expected. - -For the following 4 RSA encryption routines, it should be noted that -RSA_private_decrypt() should be used on the output from -RSA_public_encrypt() and RSA_public_decrypt() should be used on -the output from RSA_private_encrypt(). - -int RSA_public_encrypt( -int from_len; -unsigned char *from -unsigned char *to -RSA *rsa); - This function implements RSA public encryption, the rsa variable - should be a public key (but can be a private key). 'from_len' - bytes taken from 'from' and encrypted and put into 'to'. 'to' needs - to be at least RSA_size(rsa) bytes long. The number of bytes - written into 'to' is returned. -1 is returned on an error. The - operation performed is - to = from^rsa->e mod rsa->n. - -int RSA_private_encrypt( -int from_len; -unsigned char *from -unsigned char *to -RSA *rsa); - This function implements RSA private encryption, the rsa variable - should be a private key. 'from_len' bytes taken from - 'from' and encrypted and put into 'to'. 'to' needs - to be at least RSA_size(rsa) bytes long. The number of bytes - written into 'to' is returned. -1 is returned on an error. The - operation performed is - to = from^rsa->d mod rsa->n. - -int RSA_public_decrypt( -int from_len; -unsigned char *from -unsigned char *to -RSA *rsa); - This function implements RSA public decryption, the rsa variable - should be a public key (but can be a private key). 'from_len' - bytes are taken from 'from' and decrypted. The decrypted data is - put into 'to'. The number of bytes encrypted is returned. -1 is - returned to indicate an error. The operation performed is - to = from^rsa->e mod rsa->n. - -int RSA_private_decrypt( -int from_len; -unsigned char *from -unsigned char *to -RSA *rsa); - This function implements RSA private decryption, the rsa variable - should be a private key. 'from_len' bytes are taken - from 'from' and decrypted. The decrypted data is - put into 'to'. The number of bytes encrypted is returned. -1 is - returned to indicate an error. The operation performed is - to = from^rsa->d mod rsa->n. - -int RSA_mod_exp( -BIGNUM *n; -BIGNUM *p; -RSA *rsa); - Normally you will never use this routine. - This is really an internal function which is called by - RSA_private_encrypt() and RSA_private_decrypt(). It performs - n=n^p mod rsa->n except that it uses the 5 extra variables in the - RSA structure to make this more efficient. - -RSA *RSA_generate_key( -int bits; -unsigned long e; -void (*callback)(); -char *cb_arg; - This routine is used to generate RSA private keys. It takes - quite a period of time to run and should only be used to - generate initial private keys that should then be stored - for later use. The passed callback function - will be called periodically so that feedback can be given - as to how this function is progressing. - 'bits' is the length desired for the modulus, so it would be 1024 - to generate a 1024 bit private key. - 'e' is the value to use for the public exponent 'e'. Traditionally - it is set to either 3 or 0x10001. - The callback function (if not NULL) is called in the following - situations. - when we have generated a suspected prime number to test, - callback(0,num1++,cb_arg). When it passes a prime number test, - callback(1,num2++,cb_arg). When it is rejected as one of - the 2 primes required due to gcd(prime,e value) != 0, - callback(2,num3++,cb_arg). When finally accepted as one - of the 2 primes, callback(3,num4++,cb_arg). - - -==== rsaref.doc ======================================================== - -This package can be compiled to use the RSAref library. -This library is not allowed outside of the USA but inside the USA it is -claimed by RSA to be the only RSA public key library that can be used -besides BSAFE.. - -There are 2 files, rsaref/rsaref.c and rsaref/rsaref.h that contain the glue -code to use RSAref. These files were written by looking at the PGP -source code and seeing which routines it used to access RSAref. -I have also been sent by some-one a copy of the RSAref header file that -contains the library error codes. - -[ Jun 1996 update - I have recently gotten hold of RSAref 2.0 from - South Africa and have been doing some performace tests. ] - -They have now been tested against the recently announced RSAEURO -library. - -There are 2 ways to use SSLeay and RSAref. First, to build so that -the programs must be linked with RSAref, add '-DRSAref' to CFLAG in the top -level makefile and -lrsaref (or where ever you are keeping RSAref) to -EX_LIBS. - -To build a makefile via util/mk1mf.pl to do this, use the 'rsaref' option. - -The second method is to build as per normal and link applications with -the RSAglue library. The correct library order would be -cc -o cmd cmd.o -lssl -lRSAglue -lcrypto -lrsaref -ldes -The RSAglue library is built in the rsa directory and is NOT -automatically installed. - -Be warned that the RSAEURO library, that is claimed to be compatible -with RSAref contains a different value for the maximum number of bits -supported. This changes structure sizes and so if you are using -RSAEURO, change the value of RSAref_MAX_BITS in rsa/rsaref.h - - -==== s_mult.doc ======================================================== - -s_mult is a test program I hacked up on a Sunday for testing non-blocking -IO. It has a select loop at it's centre that handles multiple readers -and writers. - -Try the following command -ssleay s_mult -echo -nbio -ssl -v -echo - sends any sent text back to the sender -nbio - turns on non-blocking IO -ssl - accept SSL connections, default is normal text -v - print lots - type Q<cr> to quit - -In another window, run the following -ssleay s_client -pause </etc/termcap - -The pause option puts in a 1 second pause in each read(2)/write(2) call -so the other end will have read()s fail. - -==== session.doc ======================================================== - -I have just checked over and re-worked the session stuff. -The following brief example will ignore all setup information to do with -authentication. - -Things operate as follows. - -The SSL environment has a 'context', a SSL_CTX structure. This holds the -cached SSL_SESSIONS (which can be reused) and the certificate lookup -information. Each SSL structure needs to be associated with a SSL_CTX. -Normally only one SSL_CTX structure is needed per program. - -SSL_CTX *SSL_CTX_new(void ); -void SSL_CTX_free(SSL_CTX *); -These 2 functions create and destroy SSL_CTX structures - -The SSL_CTX has a session_cache_mode which is by default, -in SSL_SESS_CACHE_SERVER mode. What this means is that the library -will automatically add new session-id's to the cache upon successful -SSL_accept() calls. -If SSL_SESS_CACHE_CLIENT is set, then client certificates are also added -to the cache. -SSL_set_session_cache_mode(ctx,mode) will set the 'mode' and -SSL_get_session_cache_mode(ctx) will get the cache 'mode'. -The modes can be -SSL_SESS_CACHE_OFF - no caching -SSL_SESS_CACHE_CLIENT - only SSL_connect() -SSL_SESS_CACHE_SERVER - only SSL_accept() -SSL_SESS_NO_CACHE_BOTH - Either SSL_accept() or SSL_connect(). -If SSL_SESS_CACHE_NO_AUTO_CLEAR is set, old timed out sessions are -not automatically removed each 255, SSL_connect()s or SSL_accept()s. - -By default, upon every 255 successful SSL_connect() or SSL_accept()s, -the cache is flush. Please note that this could be expensive on -a heavily loaded SSL server, in which case, turn this off and -clear the cache of old entries 'manually' (with one of the functions -listed below) every few hours. Perhaps I should up this number, it is hard -to say. Remember, the '255' new calls is just a mechanism to get called -every now and then, in theory at most 255 new session-id's will have been -added but if 100 are added every minute, you would still have -500 in the cache before any would start being flushed (assuming a 3 minute -timeout).. - -int SSL_CTX_sess_hits(SSL_CTX *ctx); -int SSL_CTX_sess_misses(SSL_CTX *ctx); -int SSL_CTX_sess_timeouts(SSL_CTX *ctx); -These 3 functions return statistics about the SSL_CTX. These 3 are the -number of session id reuses. hits is the number of reuses, misses are the -number of lookups that failed, and timeouts is the number of cached -entries ignored because they had timeouted. - -ctx->new_session_cb is a function pointer to a function of type -int new_session_callback(SSL *ssl,SSL_SESSION *new); -This function, if set in the SSL_CTX structure is called whenever a new -SSL_SESSION is added to the cache. If the callback returns non-zero, it -means that the application will have to do a SSL_SESSION_free() -on the structure (this is -to do with the cache keeping the reference counts correct, without the -application needing to know about it. -The 'active' parameter is the current SSL session for which this connection -was created. - -void SSL_CTX_sess_set_new_cb(SSL_CTX *ctx,int (*cb)()); -to set the callback, -int (*cb)() SSL_CTX_sess_get_new_cb(SSL_CTX *ctx) -to get the callback. - -If the 'get session' callback is set, when a session id is looked up and -it is not in the session-id cache, this callback is called. The callback is -of the form -SSL_SESSION *get_session_callback(unsigned char *sess_id,int sess_id_len, - int *copy); - -The get_session_callback is intended to return null if no session id is found. -The reference count on the SSL_SESSION in incremented by the SSL library, -if copy is 1. Otherwise, the reference count is not modified. - -void SSL_CTX_sess_set_get_cb(ctx,cb) sets the callback and -int (*cb)()SSL_CTX_sess_get_get_cb(ctx) returns the callback. - -These callbacks are basically intended to be used by processes to -send their session-id's to other processes. I currently have not implemented -non-blocking semantics for these callbacks, it is upto the application -to make the callbacks efficient if they require blocking (perhaps -by 'saving' them and then 'posting them' when control returns from -the SSL_accept(). - -LHASH *SSL_CTX_sessions(SSL_CTX *ctx) -This returns the session cache. The lhash strucutre can be accessed for -statistics about the cache. - -void lh_stats(LHASH *lh, FILE *out); -void lh_node_stats(LHASH *lh, FILE *out); -void lh_node_usage_stats(LHASH *lh, FILE *out); - -can be used to print details about it's activity and current state. -You can also delve directly into the lhash structure for 14 different -counters that are kept against the structure. When I wrote the lhash library, -I was interested in gathering statistics :-). -Have a read of doc/lhash.doc in the SSLeay distribution area for more details -on the lhash library. - -Now as mentioned ealier, when a SSL is created, it needs a SSL_CTX. -SSL * SSL_new(SSL_CTX *); - -This stores a session. A session is secret information shared between 2 -SSL contexts. It will only be created if both ends of the connection have -authenticated their peer to their satisfaction. It basically contains -the information required to use a particular secret key cipher. - -To retrieve the SSL_CTX being used by a SSL, -SSL_CTX *SSL_get_SSL_CTX(SSL *s); - -Now when a SSL session is established between to programs, the 'session' -information that is cached in the SSL_CTX can me manipulated by the -following functions. -int SSL_set_session(SSL *s, SSL_SESSION *session); -This will set the SSL_SESSION to use for the next SSL_connect(). If you use -this function on an already 'open' established SSL connection, 'bad things -will happen'. This function is meaning-less when used on a ssl strucutre -that is just about to be used in a SSL_accept() call since the -SSL_accept() will either create a new session or retrieve one from the -cache. - -SSL_SESSION *SSL_get_session(SSL *s); -This will return the SSL_SESSION for the current SSL, NULL if there is -no session associated with the SSL structure. - -The SSL sessions are kept in the SSL_CTX in a hash table, to remove a -session -void SSL_CTX_remove_session(SSL_CTX *,SSL_SESSION *c); -and to add one -int SSL_CTX_add_session(SSL_CTX *s, SSL_SESSION *c); -SSL_CTX_add_session() returns 1 if the session was already in the cache (so it -was not added). -Whenever a new session is created via SSL_connect()/SSL_accept(), -they are automatically added to the cache, depending on the session_cache_mode -settings. SSL_set_session() -does not add it to the cache. Just call SSL_CTX_add_session() if you do want the -session added. For a 'client' this would not normally be the case. -SSL_CTX_add_session() is not normally ever used, except for doing 'evil' things -which the next 2 funtions help you do. - -int i2d_SSL_SESSION(SSL_SESSION *in,unsigned char **pp); -SSL_SESSION *d2i_SSL_SESSION(SSL_SESSION **a,unsigned char **pp,long length); -These 2 functions are in the standard ASN1 library form and can be used to -load and save to a byte format, the SSL_SESSION structure. -With these functions, you can save and read these structures to a files or -arbitary byte string. -The PEM_write_SSL_SESSION(fp,x) and PEM_read_SSL_SESSION(fp,x,cb) will -write to a file pointer in base64 encoding. - -What you can do with this, is pass session information between separate -processes. Please note, that you will probably also need to modify the -timeout information on the SSL_SESSIONs. - -long SSL_get_time(SSL_SESSION *s) -will return the 'time' that the session -was loaded. The timeout is relative to this time. This information is -saved when the SSL_SESSION is converted to binarary but it is stored -in as a unix long, which is rather OS dependant, but easy to convert back. - -long SSL_set_time(SSL_SESSION *s,long t) will set the above mentioned time. -The time value is just the value returned from time(3), and should really -be defined by be to be time_t. - -long SSL_get_timeout(SSL_SESSION *s); -long SSL_set_timeout(SSL_SESSION *s,long t); -These 2 retrieve and set the timeout which is just a number of secconds -from the 'SSL_get_time()' value. When this time period has elapesed, -the session will no longer be in the cache (well it will actually be removed -the next time it is attempted to be retrieved, so you could 'bump' -the timeout so it remains valid). -The 'time' and 'timeout' are set on a session when it is created, not reset -each time it is reused. If you did wish to 'bump it', just after establishing -a connection, do a -SSL_set_time(ssl,time(NULL)); - -You can also use -SSL_CTX_set_timeout(SSL_CTX *ctx,unsigned long t) and -SSL_CTX_get_timeout(SSL_CTX *ctx) to manipulate the default timeouts for -all SSL connections created against a SSL_CTX. If you set a timeout in -an SSL_CTX, all new SSL's created will inherit the timeout. It can be over -written by the SSL_set_timeout(SSL *s,unsigned long t) function call. -If you 'set' the timeout back to 0, the system default will be used. - -SSL_SESSION *SSL_SESSION_new(); -void SSL_SESSION_free(SSL_SESSION *ses); -These 2 functions are used to create and dispose of SSL_SESSION functions. -You should not ever normally need to use them unless you are using -i2d_SSL_SESSION() and/or d2i_SSL_SESSION(). If you 'load' a SSL_SESSION -via d2i_SSL_SESSION(), you will need to SSL_SESSION_free() it. -Both SSL_set_session() and SSL_CTX_add_session() will 'take copies' of the -structure (via reference counts) when it is passed to them. - -SSL_CTX_flush_sessions(ctx,time); -The first function will clear all sessions from the cache, which have expired -relative to 'time' (which could just be time(NULL)). - -SSL_CTX_flush_sessions(ctx,0); -This is a special case that clears everything. - -As a final comment, a 'session' is not enough to establish a new -connection. If a session has timed out, a certificate and private key -need to have been associated with the SSL structure. -SSL_copy_session_id(SSL *to,SSL *from); will copy not only the session -strucutre but also the private key and certificate associated with -'from'. - -EXAMPLES. - -So lets play at being a weird SSL server. - -/* setup a context */ -ctx=SSL_CTX_new(); - -/* Lets load some session from binary into the cache, why one would do - * this is not toally clear, but passing between programs does make sense - * Perhaps you are using 4096 bit keys and are happy to keep them - * valid for a week, to avoid the RSA overhead of 15 seconds, I'm not toally - * sure, perhaps this is a process called from an SSL inetd and this is being - * passed to the application. */ -session=d2i_SSL_SESSION(....) -SSL_CTX_add_session(ctx,session); - -/* Lets even add a session from a file */ -session=PEM_read_SSL_SESSION(....) -SSL_CTX_add_session(ctx,session); - -/* create a new SSL structure */ -ssl=SSL_new(ctx); - -/* At this point we want to be able to 'create' new session if - * required, so we need a certificate and RSAkey. */ -SSL_use_RSAPrivateKey_file(ssl,...) -SSL_use_certificate_file(ssl,...) - -/* Now since we are a server, it make little sence to load a session against - * the ssl strucutre since a SSL_accept() will either create a new session or - * grab an existing one from the cache. */ - -/* grab a socket descriptor */ -fd=accept(...); - -/* associated it with the ssl strucutre */ -SSL_set_fd(ssl,fd); - -SSL_accept(ssl); /* 'do' SSL using out cert and RSA key */ - -/* Lets print out the session details or lets save it to a file, - * perhaps with a secret key cipher, so that we can pass it to the FBI - * when they want to decode the session :-). While we have RSA - * this does not matter much but when I do SSLv3, this will allow a mechanism - * for the server/client to record the information needed to decode - * the traffic that went over the wire, even when using Diffie-Hellman */ -PEM_write_SSL_SESSION(SSL_get_session(ssl),stdout,....) - -Lets 'connect' back to the caller using the same session id. - -ssl2=SSL_new(ctx); -fd2=connect(them); -SSL_set_fd(ssl2,fd2); -SSL_set_session(ssl2,SSL_get_session(ssl)); -SSL_connect(ssl2); - -/* what the hell, lets accept no more connections using this session */ -SSL_CTX_remove_session(SSL_get_SSL_CTX(ssl),SSL_get_session(ssl)); - -/* we could have just as easily used ssl2 since they both are using the - * same session. - * You will note that both ssl and ssl2 are still using the session, and - * the SSL_SESSION structure will be free()ed when both ssl and ssl2 - * finish using the session. Also note that you could continue to initiate - * connections using this session by doing SSL_get_session(ssl) to get the - * existing session, but SSL_accept() will not be able to find it to - * use for incoming connections. - * Of corse, the session will timeout at the far end and it will no - * longer be accepted after a while. The time and timeout are ignored except - * by SSL_accept(). */ - -/* Since we have had our server running for 10 weeks, and memory is getting - * short, perhaps we should clear the session cache to remove those - * 100000 session entries that have expired. Some may consider this - * a memory leak :-) */ - -SSL_CTX_flush_sessions(ctx,time(NULL)); - -/* Ok, after a bit more time we wish to flush all sessions from the cache - * so that all new connections will be authenticated and incure the - * public key operation overhead */ - -SSL_CTX_flush_sessions(ctx,0); - -/* As a final note, to copy everything to do with a SSL, use */ -SSL_copy_session_id(SSL *to,SSL *from); -/* as this also copies the certificate and RSA key so new session can - * be established using the same details */ - - -==== sha.doc ======================================================== - -The SHA (Secure Hash Algorithm) library. -SHA is a message digest algorithm that can be used to condense an arbitrary -length message down to a 20 byte hash. The functions all need to be passed -a SHA_CTX which is used to hold the SHA context during multiple SHA_Update() -function calls. The normal method of use for this library is as follows -This library contains both SHA and SHA-1 digest algorithms. SHA-1 is -an update to SHA (which should really be called SHA-0 now) which -tweaks the algorithm slightly. The SHA-1 algorithm is used by simply -using SHA1_Init(), SHA1_Update(), SHA1_Final() and SHA1() instead of the -SHA*() calls - -SHA_Init(...); -SHA_Update(...); -... -SHA_Update(...); -SHA_Final(...); - -This library requires the inclusion of 'sha.h'. - -The functions are as follows: - -void SHA_Init( -SHA_CTX *c); - This function needs to be called to initiate a SHA_CTX structure for - use. - -void SHA_Update( -SHA_CTX *c; -unsigned char *data; -unsigned long len); - This updates the message digest context being generated with 'len' - bytes from the 'data' pointer. The number of bytes can be any - length. - -void SHA_Final( -unsigned char *md; -SHA_CTX *c; - This function is called when a message digest of the data digested - with SHA_Update() is wanted. The message digest is put in the 'md' - array and is SHA_DIGEST_LENGTH (20) bytes long. - -unsigned char *SHA( -unsigned char *d; -unsigned long n; -unsigned char *md; - This function performs a SHA_Init(), followed by a SHA_Update() - followed by a SHA_Final() (using a local SHA_CTX). - The resulting digest is put into 'md' if it is not NULL. - Regardless of the value of 'md', the message - digest is returned from the function. If 'md' was NULL, the message - digest returned is being stored in a static structure. - - -==== speed.doc ======================================================== - -To get an idea of the performance of this library, use -ssleay speed - -perl util/sp-diff.pl file1 file2 - -will print out the relative differences between the 2 files which are -expected to be the output from the speed program. - -The performace of the library is very dependant on the Compiler -quality and various flags used to build. - ---- - -These are some numbers I did comparing RSAref and SSLeay on a Pentium 100. -[ These numbers are all out of date, as of SSL - 0.6.1 the RSA -operations are about 2 times faster, so check the version number ] - -RSA performance. - -SSLeay 0.6.0 -Pentium 100, 32meg, Windows NT Workstation 3.51 -linux - gcc v 2.7.0 -O3 -fomit-frame-pointer -m486 -and -Windows NT - Windows NT 3.51 - Visual C++ 4.1 - 586 code + 32bit assember -Windows 3.1 - Windows NT 3.51 - Visual C++ 1.52c - 286 code + 32bit assember -NT Dos Shell- Windows NT 3.51 - Visual C++ 1.52c - 286 code + 16bit assember - -Times are how long it takes to do an RSA private key operation. - - 512bits 1024bits -------------------------------- -SSLeay NT dll 0.042s 0.202s see above -SSLeay linux 0.046s 0.218s Assember inner loops (normal build) -SSLeay linux 0.067s 0.380s Pure C code with BN_LLONG defined -SSLeay W3.1 dll 0.108s 0.478s see above -SSLeay linux 0.109s 0.713s C without BN_LLONG. -RSAref2.0 linux 0.149s 0.936s -SSLeay MS-DOS 0.197s 1.049s see above - -486DX66, 32meg, Windows NT Server 3.51 - 512bits 1024bits -------------------------------- -SSLeay NT dll 0.084s 0.495s <- SSLeay 0.6.3 -SSLeay NT dll 0.154s 0.882s -SSLeay W3.1 dll 0.335s 1.538s -SSLeay MS-DOS 0.490s 2.790s - -What I find cute is that I'm still faster than RSAref when using standard C, -without using the 'long long' data type :-), %35 faster for 512bit and we -scale up to 3.2 times faster for the 'default linux' build. I should mention -that people should 'try' to use either x86-lnx.s (elf), x86-lnxa.s or -x86-sol.s for any x86 based unix they are building on. The only problems -with be with syntax but the performance gain is quite large, especially for -servers. The code is very simple, you just need to modify the 'header'. - -The message is, if you are stuck using RSAref, the RSA performance will be -bad. Considering the code was compiled for a pentium, the 486DX66 number -would indicate 'Use RSAref and turn you Pentium 100 into a 486DX66' :-). -[ As of verson 0.6.1, it would be correct to say 'turn you pentium 100 - into a 486DX33' :-) ] - -I won't tell people if the DLL's are using RSAref or my stuff if no-one -asks :-). - -eric - -PS while I know I could speed things up further, I will probably not do - so due to the effort involved. I did do some timings on the - SSLeay bignum format -> RSAref number format conversion that occurs - each time RSAref is used by SSLeay, and the numbers are trivial. - 0.00012s a call for 512bit vs 0.149s for the time spent in the function. - 0.00018s for 1024bit vs 0.938s. Insignificant. - So the 'way to go', to support faster RSA libraries, if people are keen, - is to write 'glue' code in a similar way that I do for RSAref and send it - to me :-). - My base library still has the advantage of being able to operate on - any size numbers, and is not that far from the performance from the - leaders in the field. (-%30?) - [ Well as of 0.6.1 I am now the leader in the filed on x86 (we at - least very close :-) ] - - I suppose I should also mention some other numbers RSAref numbers, again - on my Pentium. - DES CBC EDE-DES MD5 - RSAref linux 830k/s 302k/s 4390k/s - SSLeay linux 855k/s 319k/s 10025k/s - SSLeay NT 1158k/s 410k/s 10470k/s - SSLeay w31 378k/s 143k/s 2383k/s (fully 16bit) - - Got to admit that Visual C++ 4.[01] is a damn fine compiler :-) --- -Eric Young | BOOL is tri-state according to Bill Gates. -AARNet: eay@cryptsoft.com | RTFM Win32 GetMessage(). - - - - -==== ssl-ciph.doc ======================================================== - -This is a quick high level summery of how things work now. - -Each SSLv2 and SSLv3 cipher is composed of 4 major attributes plus a few extra -minor ones. - -They are 'The key exchange algorithm', which is RSA for SSLv2 but can also -be Diffle-Hellman for SSLv3. - -An 'Authenticion algorithm', which can be RSA, Diffle-Helman, DSS or -none. - -The cipher - -The MAC digest. - -A cipher can also be an export cipher and is either an SSLv2 or a -SSLv3 ciphers. - -To specify which ciphers to use, one can either specify all the ciphers, -one at a time, or use 'aliases' to specify the preference and order for -the ciphers. - -There are a large number of aliases, but the most importaint are -kRSA, kDHr, kDHd and kDHE for key exchange types. - -aRSA, aDSS, aNULL and aDH for authentication -DES, 3DES, RC4, RC2, IDEA and eNULL for ciphers -MD5, SHA0 and SHA1 digests - -Now where this becomes interesting is that these can be put together to -specify the order and ciphers you wish to use. - -To speed this up there are also aliases for certian groups of ciphers. -The main ones are -SSLv2 - all SSLv2 ciphers -SSLv3 - all SSLv3 ciphers -EXP - all export ciphers -LOW - all low strngth ciphers (no export ciphers, normally single DES) -MEDIUM - 128 bit encryption -HIGH - Triple DES - -These aliases can be joined in a : separated list which specifies to -add ciphers, move them to the current location and delete them. - -A simpler way to look at all of this is to use the 'ssleay ciphers -v' command. -The default library cipher spec is -!ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP -which means, first, remove from consideration any ciphers that do not -authenticate. Next up, use ciphers using RC4 and RSA. Next include the HIGH, -MEDIUM and the LOW security ciphers. Finish up by adding all the export -ciphers on the end, then 'pull' all the SSLv2 and export ciphers to -the end of the list. - -The results are -$ ssleay ciphers -v '!ADH:RC4+RSA:HIGH:MEDIUM:LOW:EXP:+SSLv2:+EXP' - -RC4-SHA SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=SHA1 -RC4-MD5 SSLv3 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 -EDH-RSA-DES-CBC3-SHA SSLv3 Kx=DH Au=RSA Enc=3DES(168) Mac=SHA1 -EDH-DSS-DES-CBC3-SHA SSLv3 Kx=DH Au=DSS Enc=3DES(168) Mac=SHA1 -DES-CBC3-SHA SSLv3 Kx=RSA Au=RSA Enc=3DES(168) Mac=SHA1 -IDEA-CBC-MD5 SSLv3 Kx=RSA Au=RSA Enc=IDEA(128) Mac=SHA1 -EDH-RSA-DES-CBC-SHA SSLv3 Kx=DH Au=RSA Enc=DES(56) Mac=SHA1 -EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH Au=DSS Enc=DES(56) Mac=SHA1 -DES-CBC-SHA SSLv3 Kx=RSA Au=RSA Enc=DES(56) Mac=SHA1 -DES-CBC3-MD5 SSLv2 Kx=RSA Au=RSA Enc=3DES(168) Mac=MD5 -DES-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=DES(56) Mac=MD5 -IDEA-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=IDEA(128) Mac=MD5 -RC2-CBC-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC2(128) Mac=MD5 -RC4-MD5 SSLv2 Kx=RSA Au=RSA Enc=RC4(128) Mac=MD5 -EXP-EDH-RSA-DES-CBC SSLv3 Kx=DH(512) Au=RSA Enc=DES(40) Mac=SHA1 export -EXP-EDH-DSS-DES-CBC-SHA SSLv3 Kx=DH(512) Au=DSS Enc=DES(40) Mac=SHA1 export -EXP-DES-CBC-SHA SSLv3 Kx=RSA(512) Au=RSA Enc=DES(40) Mac=SHA1 export -EXP-RC2-CBC-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export -EXP-RC4-MD5 SSLv3 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export -EXP-RC2-CBC-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC2(40) Mac=MD5 export -EXP-RC4-MD5 SSLv2 Kx=RSA(512) Au=RSA Enc=RC4(40) Mac=MD5 export - -I would recoment people use the 'ssleay ciphers -v "text"' -command to check what they are going to use. - -Anyway, I'm falling asleep here so I'll do some more tomorrow. - -eric - -==== ssl.doc ======================================================== - -SSL_CTX_sessions(SSL_CTX *ctx) - the session-id hash table. - -/* Session-id cache stats */ -SSL_CTX_sess_number -SSL_CTX_sess_connect -SSL_CTX_sess_connect_good -SSL_CTX_sess_accept -SSL_CTX_sess_accept_good -SSL_CTX_sess_hits -SSL_CTX_sess_cb_hits -SSL_CTX_sess_misses -SSL_CTX_sess_timeouts - -/* Session-id application notification callbacks */ -SSL_CTX_sess_set_new_cb -SSL_CTX_sess_get_new_cb -SSL_CTX_sess_set_get_cb -SSL_CTX_sess_get_get_cb - -/* Session-id cache operation mode */ -SSL_CTX_set_session_cache_mode -SSL_CTX_get_session_cache_mode - -/* Set default timeout values to use. */ -SSL_CTX_set_timeout -SSL_CTX_get_timeout - -/* Global SSL initalisation informational callback */ -SSL_CTX_set_info_callback -SSL_CTX_get_info_callback -SSL_set_info_callback -SSL_get_info_callback - -/* If the SSL_accept/SSL_connect returned with -1, these indicate when - * we should re-call *. -SSL_want -SSL_want_nothing -SSL_want_read -SSL_want_write -SSL_want_x509_lookup - -/* Where we are in SSL initalisation, used in non-blocking, perhaps - * have a look at ssl/bio_ssl.c */ -SSL_state -SSL_is_init_finished -SSL_in_init -SSL_in_connect_init -SSL_in_accept_init - -/* Used to set the 'inital' state so SSL_in_connect_init and SSL_in_accept_init - * can be used to work out which function to call. */ -SSL_set_connect_state -SSL_set_accept_state - -/* Where to look for certificates for authentication */ -SSL_set_default_verify_paths /* calles SSL_load_verify_locations */ -SSL_load_verify_locations - -/* get info from an established connection */ -SSL_get_session -SSL_get_certificate -SSL_get_SSL_CTX - -SSL_CTX_new -SSL_CTX_free -SSL_new -SSL_clear -SSL_free - -SSL_CTX_set_cipher_list -SSL_get_cipher -SSL_set_cipher_list -SSL_get_cipher_list -SSL_get_shared_ciphers - -SSL_accept -SSL_connect -SSL_read -SSL_write - -SSL_debug - -SSL_get_read_ahead -SSL_set_read_ahead -SSL_set_verify - -SSL_pending - -SSL_set_fd -SSL_set_rfd -SSL_set_wfd -SSL_set_bio -SSL_get_fd -SSL_get_rbio -SSL_get_wbio - -SSL_use_RSAPrivateKey -SSL_use_RSAPrivateKey_ASN1 -SSL_use_RSAPrivateKey_file -SSL_use_PrivateKey -SSL_use_PrivateKey_ASN1 -SSL_use_PrivateKey_file -SSL_use_certificate -SSL_use_certificate_ASN1 -SSL_use_certificate_file - -ERR_load_SSL_strings -SSL_load_error_strings - -/* human readable version of the 'state' of the SSL connection. */ -SSL_state_string -SSL_state_string_long -/* These 2 report what kind of IO operation the library was trying to - * perform last. Probably not very usefull. */ -SSL_rstate_string -SSL_rstate_string_long - -SSL_get_peer_certificate - -SSL_SESSION_new -SSL_SESSION_print_fp -SSL_SESSION_print -SSL_SESSION_free -i2d_SSL_SESSION -d2i_SSL_SESSION - -SSL_get_time -SSL_set_time -SSL_get_timeout -SSL_set_timeout -SSL_copy_session_id -SSL_set_session -SSL_CTX_add_session -SSL_CTX_remove_session -SSL_CTX_flush_sessions - -BIO_f_ssl - -/* used to hold information as to why a certificate verification failed */ -SSL_set_verify_result -SSL_get_verify_result - -/* can be used by the application to associate data with an SSL structure. - * It needs to be 'free()ed' by the application */ -SSL_set_app_data -SSL_get_app_data - -/* The following all set values that are kept in the SSL_CTX but - * are used as the default values when an SSL session is created. - * They are over writen by the relevent SSL_xxxx functions */ - -/* SSL_set_verify */ -void SSL_CTX_set_default_verify - -/* This callback, if set, totaly overrides the normal SSLeay verification - * functions and should return 1 on success and 0 on failure */ -void SSL_CTX_set_cert_verify_callback - -/* The following are the same as the equivilent SSL_xxx functions. - * Only one copy of this information is kept and if a particular - * SSL structure has a local override, it is totally separate structure. - */ -int SSL_CTX_use_RSAPrivateKey -int SSL_CTX_use_RSAPrivateKey_ASN1 -int SSL_CTX_use_RSAPrivateKey_file -int SSL_CTX_use_PrivateKey -int SSL_CTX_use_PrivateKey_ASN1 -int SSL_CTX_use_PrivateKey_file -int SSL_CTX_use_certificate -int SSL_CTX_use_certificate_ASN1 -int SSL_CTX_use_certificate_file - - -==== ssl_ctx.doc ======================================================== - -This is now a bit dated, quite a few of the SSL_ functions could be -SSL_CTX_ functions. I will update this in the future. 30 Aug 1996 - -From eay@orb.mincom.oz.au Mon Dec 11 21:37:08 1995 -Received: by orb.mincom.oz.au id AA00696 - (5.65c/IDA-1.4.4 for eay); Mon, 11 Dec 1995 11:37:08 +1000 -Date: Mon, 11 Dec 1995 11:37:08 +1000 (EST) -From: Eric Young <eay@mincom.oz.au> -X-Sender: eay@orb -To: sameer <sameer@c2.org> -Cc: Eric Young <eay@mincom.oz.au> -Subject: Re: PEM_readX509 oesn't seem to be working -In-Reply-To: <199512110102.RAA12521@infinity.c2.org> -Message-Id: <Pine.SOL.3.91.951211112115.28608D-100000@orb> -Mime-Version: 1.0 -Content-Type: TEXT/PLAIN; charset=US-ASCII -Status: RO -X-Status: - -On Sun, 10 Dec 1995, sameer wrote: -> OK, that's solved. I've found out that it is saying "no -> certificate set" in SSL_accept because s->conn == NULL -> so there is some place I need to initialize s->conn that I am -> not initializing it. - -The full order of things for a server should be. - -ctx=SSL_CTX_new(); - -/* The next line should not really be using ctx->cert but I'll leave it - * this way right now... I don't want a X509_ routine to know about an SSL - * structure, there should be an SSL_load_verify_locations... hmm, I may - * add it tonight. - */ -X509_load_verify_locations(ctx->cert,CAfile,CApath); - -/* Ok now for each new connection we do the following */ -con=SSL_new(ctx); -SSL_set_fd(con,s); -SSL_set_verify(con,verify,verify_callback); - -/* set the certificate and private key to use. */ -SSL_use_certificate_ASN1(con,X509_certificate); -SSL_use_RSAPrivateKey_ASN1(con,RSA_private_key); - -SSL_accept(con); - -SSL_read(con)/SSL_write(con); - -There is a bit more than that but that is basically the structure. - -Create a context and specify where to lookup certificates. - -foreach connection - { - create a SSL structure - set the certificate and private key - do a SSL_accept - - we should now be ok - } - -eric --- -Eric Young | Signature removed since it was generating -AARNet: eay@mincom.oz.au | more followups than the message contents :-) - - - -==== ssleay.doc ======================================================== - -SSLeay: a cryptographic kitchen sink. - -1st December 1995 -Way back at the start of April 1995, I was looking for a mindless -programming project. A friend of mine (Tim Hudson) said "why don't you do SSL, -it has DES encryption in it and I would not mind using it in a SSL telnet". -While it was true I had written a DES library in previous years, litle -did I know what an expansive task SSL would turn into. - -First of all, the SSL protocol contains DES encryption. Well and good. My -DES library was fast and portable. It also contained the RSA's RC4 stream -cipher. Again, not a problem, some-one had just posted to sci.crypt -something that was claimed to be RC4. It also contained IDEA, I had the -specifications, not a problem to implement. MD5, an RFC, trivial, at most -I could spend a week or so trying to see if I could speed up the -implementation. All in all a nice set of ciphers. -Then the first 'expantion of the scope', RSA public key -encryption. Since I did not knowing a thing about public key encryption -or number theory, this appeared quite a daunting task. Just writing a -big number library would be problomatic in itself, let alone making it fast. -At this point the scope of 'implementing SSL' expands eponentialy. -First of all, the RSA private keys were being kept in ASN.1 format. -Thankfully the RSA PKCS series of documents explains this format. So I now -needed to be able to encode and decode arbitary ASN.1 objects. The Public -keys were embeded in X509 certificates. Hmm... these are not only -ASN.1 objects but they make up a heirachy of authentication. To -authenticate a X509 certificate one needs to retrieve it's issuers -certificate etc etc. Hmm..., so I also need to implement some kind -of certificate management software. I would also have to implement -software to authenticate certificates. At this point the support code made -the SSL part of my library look quite small. -Around this time, the first version of SSLeay was released. - -Ah, but here was the problem, I was not happy with the code so far. As may -have become obvious, I had been treating all of this as a learning -exersize, so I have completely written the library myself. As such, due -to the way it had grown like a fungus, much of the library was not -'elagent' or neat. There were global and static variables all over the -place, the SSL part did not even handle non-blocking IO. -The Great rewrite began. - -As of this point in time, the 'Great rewrite' has almost finished. So what -follows is an approximate list of what is actually SSLeay 0.5.0 - -/********* This needs to be updated for 0.6.0+ *************/ - ---- -The library contains the following routines. Please note that most of these -functions are not specfic for SSL or any other particular cipher -implementation. I have tried to make all the routines as general purpose -as possible. So you should not think of this library as an SSL -implemtation, but rather as a library of cryptographic functions -that also contains SSL. I refer to each of these function groupings as -libraries since they are often capable of functioning as independant -libraries - -First up, the general ciphers and message digests supported by the library. - -MD2 rfc???, a standard 'by parts' interface to this algorithm. -MD5 rfc???, the same type of interface as for the MD2 library except a - different algorithm. -SHA THe Secure Hash Algorithm. Again the same type of interface as - MD2/MD5 except the digest is 20 bytes. -SHA1 The 'revised' version of SHA. Just about identical to SHA except - for one tweak of an inner loop. -DES This is my libdes library that has been floating around for the last - few years. It has been enhanced for no other reason than completeness. - It now supports ecb, cbc, cfb, ofb, cfb64, ofb64 in normal mode and - triple DES modes of ecb, cbc, cfb64 and ofb64. cfb64 and ofb64 are - functional interfaces to the 64 bit modes of cfb and ofb used in - such a way thay they function as single character interfaces. -RC4 The RSA Inc. stream cipher. -RC2 The RSA Inc. block cipher. -IDEA An implmentation of the IDEA cipher, the library supports ecb, cbc, - cfb64 and ofb64 modes of operation. - -Now all the above mentioned ciphers and digests libraries support high -speed, minimal 'crap in the way' type interfaces. For fastest and -lowest level access, these routines should be used directly. - -Now there was also the matter of public key crypto systems. These are -based on large integer arithmatic. - -BN This is my large integer library. It supports all the normal - arithmentic operations. It uses malloc extensivly and as such has - no limits of the size of the numbers being manipulated. If you - wish to use 4000 bit RSA moduli, these routines will handle it. - This library also contains routines to 'generate' prime numbers and - to test for primality. The RSA and DH libraries sit on top of this - library. As of this point in time, I don't support SHA, but - when I do add it, it will just sit on top of the routines contained - in this library. -RSA This implements the RSA public key algorithm. It also contains - routines that will generate a new private/public key pair. - All the RSA functions conform to the PKCS#1 standard. -DH This is an implementation of the - Diffie-Hellman protocol. There are all the require routines for - the protocol, plus extra routines that can be used to generate a - strong prime for use with a specified generator. While this last - routine is not generally required by applications implementing DH, - It is present for completeness and because I thing it is much - better to be able to 'generate' your own 'magic' numbers as oposed - to using numbers suplied by others. I conform to the PKCS#3 - standard where required. - -You may have noticed the preceeding section mentions the 'generation' of -prime numbers. Now this requries the use of 'random numbers'. - -RAND This psuedo-random number library is based on MD5 at it's core - and a large internal state (2k bytes). Once you have entered enough - seed data into this random number algorithm I don't feel - you will ever need to worry about it generating predictable output. - Due to the way I am writing a portable library, I have left the - issue of how to get good initial random seed data upto the - application but I do have support routines for saving and loading a - persistant random number state for use between program runs. - -Now to make all these ciphers easier to use, a higher level -interface was required. In this form, the same function would be used to -encrypt 'by parts', via any one of the above mentioned ciphers. - -EVP The Digital EnVeloPe library is quite large. At it's core are - function to perform encryption and decryption by parts while using - an initial parameter to specify which of the 17 different ciphers - or 4 different message digests to use. On top of these are implmented - the digital signature functions, sign, verify, seal and open. - Base64 encoding of binary data is also done in this library. - -PEM rfc???? describe the format for Privacy Enhanced eMail. - As part of this standard, methods of encoding digital enveloped - data is an ascii format are defined. As such, I use a form of these - to encode enveloped data. While at this point in time full support - for PEM has not been built into the library, a minimal subset of - the secret key and Base64 encoding is present. These reoutines are - mostly used to Ascii encode binary data with a 'type' associated - with it and perhaps details of private key encryption used to - encrypt the data. - -PKCS7 This is another Digital Envelope encoding standard which uses ASN.1 - to encode the data. At this point in time, while there are some - routines to encode and decode this binary format, full support is - not present. - -As Mentioned, above, there are several different ways to encode -data structures. - -ASN1 This library is more a set of primatives used to encode the packing - and unpacking of data structures. It is used by the X509 - certificate standard and by the PKCS standards which are used by - this library. It also contains routines for duplicating and signing - the structures asocisated with X509. - -X509 The X509 library contains routines for packing and unpacking, - verifying and just about every thing else you would want to do with - X509 certificates. - -PKCS7 PKCS-7 is a standard for encoding digital envelope data - structures. At this point in time the routines will load and save - DER forms of these structees. They need to be re-worked to support - the BER form which is the normal way PKCS-7 is encoded. If the - previous 2 sentances don't make much sense, don't worry, this - library is not used by this version of SSLeay anyway. - -OBJ ASN.1 uses 'object identifiers' to identify objects. A set of - functions were requred to translate from ASN.1 to an intenger, to a - character string. This library provieds these translations - -Now I mentioned an X509 library. X509 specified a hieachy of certificates -which needs to be traversed to authenticate particular certificates. - -METH This library is used to push 'methods' of retrieving certificates - into the library. There are some supplied 'methods' with SSLeay - but applications can add new methods if they so desire. - This library has not been finished and is not being used in this - version. - -Now all the above are required for use in the initial point of this project. - -SSL The SSL protocol. This is a full implmentation of SSL v 2. It - support both server and client authentication. SSL v 3 support - will be added when the SSL v 3 specification is released in it's - final form. - -Now quite a few of the above mentioned libraries rely on a few 'complex' -data structures. For each of these I have a library. - -Lhash This is a hash table library which is used extensivly. - -STACK An implemetation of a Stack data structure. - -BUF A simple character array structure that also support a function to - check that the array is greater that a certain size, if it is not, - it is realloced so that is it. - -TXT_DB A simple memory based text file data base. The application can specify - unique indexes that will be enforced at update time. - -CONF Most of the programs written for this library require a configuration - file. Instead of letting programs constantly re-implment this - subsystem, the CONF library provides a consistant and flexable - interface to not only configuration files but also environment - variables. - -But what about when something goes wrong? -The one advantage (and perhaps disadvantage) of all of these -functions being in one library was the ability to implement a -single error reporting system. - -ERR This library is used to report errors. The error system records - library number, function number (in the library) and reason - number. Multiple errors can be reported so that an 'error' trace - is created. The errors can be printed in numeric or textual form. - - -==== ssluse.doc ======================================================== - -We have an SSL_CTX which contains global information for lots of -SSL connections. The session-id cache and the certificate verificate cache. -It also contains default values for use when certificates are used. - -SSL_CTX - default cipher list - session-id cache - certificate cache - default session-id timeout period - New session-id callback - Required session-id callback - session-id stats - Informational callback - Callback that is set, overrides the SSLeay X509 certificate - verification - The default Certificate/Private Key pair - Default read ahead mode. - Default verify mode and verify callback. These are not used - if the over ride callback mentioned above is used. - -Each SSL can have the following defined for it before a connection is made. - -Certificate -Private key -Ciphers to use -Certificate verify mode and callback -IO object to use in the comunication. -Some 'read-ahead' mode information. -A previous session-id to re-use. - -A connection is made by using SSL_connect or SSL_accept. -When non-blocking IO is being used, there are functions that can be used -to determin where and why the SSL_connect or SSL_accept did not complete. -This information can be used to recall the functions when the 'error' -condition has dissapeared. - -After the connection has been made, information can be retrived about the -SSL session and the session-id values that have been decided upon. -The 'peer' certificate can be retrieved. - -The session-id values include -'start time' -'timeout length' - - - -==== stack.doc ======================================================== - -The stack data structure is used to store an ordered list of objects. -It is basically misnamed to call it a stack but it can function that way -and that is what I originally used it for. Due to the way element -pointers are kept in a malloc()ed array, the most efficient way to use this -structure is to add and delete elements from the end via sk_pop() and -sk_push(). If you wish to do 'lookups' sk_find() is quite efficient since -it will sort the stack (if required) and then do a binary search to lookup -the requested item. This sorting occurs automatically so just sk_push() -elements on the stack and don't worry about the order. Do remember that if -you do a sk_find(), the order of the elements will change. - -You should never need to 'touch' this structure directly. -typedef struct stack_st - { - unsigned int num; - char **data; - int sorted; - - unsigned int num_alloc; - int (*comp)(); - } STACK; - -'num' holds the number of elements in the stack, 'data' is the array of -elements. 'sorted' is 1 is the list has been sorted, 0 if not. - -num_alloc is the number of 'nodes' allocated in 'data'. When num becomes -larger than num_alloc, data is realloced to a larger size. -If 'comp' is set, it is a function that is used to compare 2 of the items -in the stack. The function should return -1, 0 or 1, depending on the -ordering. - -#define sk_num(sk) ((sk)->num) -#define sk_value(sk,n) ((sk)->data[n]) - -These 2 macros should be used to access the number of elements in the -'stack' and to access a pointer to one of the values. - -STACK *sk_new(int (*c)()); - This creates a new stack. If 'c', the comparison function, is not -specified, the various functions that operate on a sorted 'stack' will not -work (sk_find()). NULL is returned on failure. - -void sk_free(STACK *); - This function free()'s a stack structure. The elements in the -stack will not be freed so one should 'pop' and free all elements from the -stack before calling this function or call sk_pop_free() instead. - -void sk_pop_free(STACK *st; void (*func)()); - This function calls 'func' for each element on the stack, passing -the element as the argument. sk_free() is then called to free the 'stack' -structure. - -int sk_insert(STACK *sk,char *data,int where); - This function inserts 'data' into stack 'sk' at location 'where'. -If 'where' is larger that the number of elements in the stack, the element -is put at the end. This function tends to be used by other 'stack' -functions. Returns 0 on failure, otherwise the number of elements in the -new stack. - -char *sk_delete(STACK *st,int loc); - Remove the item a location 'loc' from the stack and returns it. -Returns NULL if the 'loc' is out of range. - -char *sk_delete_ptr(STACK *st, char *p); - If the data item pointed to by 'p' is in the stack, it is deleted -from the stack and returned. NULL is returned if the element is not in the -stack. - -int sk_find(STACK *st,char *data); - Returns the location that contains a value that is equal to -the 'data' item. If the comparison function was not set, this function -does a linear search. This function actually qsort()s the stack if it is not -in order and then uses bsearch() to do the initial search. If the -search fails,, -1 is returned. For mutliple items with the same -value, the index of the first in the array is returned. - -int sk_push(STACK *st,char *data); - Append 'data' to the stack. 0 is returned if there is a failure -(due to a malloc failure), else 1. This is -sk_insert(st,data,sk_num(st)); - -int sk_unshift(STACK *st,char *data); - Prepend 'data' to the front (location 0) of the stack. This is -sk_insert(st,data,0); - -char *sk_shift(STACK *st); - Return and delete from the stack the first element in the stack. -This is sk_delete(st,0); - -char *sk_pop(STACK *st); - Return and delete the last element on the stack. This is -sk_delete(st,sk_num(sk)-1); - -void sk_zero(STACK *st); - Removes all items from the stack. It does not 'free' -pointers but is a quick way to clear a 'stack of references'. - -==== threads.doc ======================================================== - -How to compile SSLeay for multi-threading. - -Well basically it is quite simple, set the compiler flags and build. -I have only really done much testing under Solaris and Windows NT. -If you library supports localtime_r() and gmtime_r() add, --DTHREADS to the makefile parameters. You can probably survive with out -this define unless you are going to have multiple threads generating -certificates at once. It will not affect the SSL side of things. - -The approach I have taken to doing locking is to make the application provide -callbacks to perform locking and so that the SSLeay library can distinguish -between threads (for the error state). - -To have a look at an example program, 'cd mt; vi mttest.c'. -To build under solaris, sh solaris.sh, for Windows NT or Windows 95, -win32.bat - -This will build mttest which will fire up 10 threads that talk SSL -to each other 10 times. -To enable everything to work, the application needs to call - -CRYPTO_set_id_callback(id_function); -CRYPTO_set_locking_callback(locking_function); - -before any multithreading is started. -id_function does not need to be defined under Windows NT or 95, the -correct function will be called if it is not. Under unix, getpid() -is call if the id_callback is not defined, for Solaris this is wrong -(since threads id's are not pid's) but under Linux it is correct -(threads are just processes sharing the data segement). - -The locking_callback is used to perform locking by the SSLeay library. -eg. - -void solaris_locking_callback(mode,type,file,line) -int mode; -int type; -char *file; -int line; - { - if (mode & CRYPTO_LOCK) - mutex_lock(&(lock_cs[type])); - else - mutex_unlock(&(lock_cs[type])); - } - -Now in this case I have used mutexes instead of read/write locks, since they -are faster and there are not many read locks in SSLeay, you may as well -always use write locks. file and line are __FILE__ and __LINE__ from -the compile and can be usefull when debugging. - -Now as you can see, 'type' can be one of a range of values, these values are -defined in crypto/crypto.h -CRYPTO_get_lock_name(type) will return a text version of what the lock is. -There are CRYPTO_NUM_LOCKS locks required, so under solaris, the setup -for multi-threading can be - -static mutex_t lock_cs[CRYPTO_NUM_LOCKS]; - -void thread_setup() - { - int i; - - for (i=0; i<CRYPTO_NUM_LOCKS; i++) - mutex_init(&(lock_cs[i]),USYNC_THREAD,NULL); - CRYPTO_set_id_callback((unsigned long (*)())solaris_thread_id); - CRYPTO_set_locking_callback((void (*)())solaris_locking_callback); - } - -As a final note, under Windows NT or Windows 95, you have to be careful -not to mix the various threaded, unthreaded and debug libraries. -Normally if they are mixed incorrectly, mttest will crash just after printing -out some usage statistics at the end. This is because the -different system libraries use different malloc routines and if -data is malloc()ed inside crypt32.dll or ssl32.dll and then free()ed by a -different library malloc, things get very confused. - -The default SSLeay DLL builds use /MD, so if you use this on your -application, things will work as expected. If you use /MDd, -you will probably have to rebuild SSLeay using this flag. -I should modify util/mk1mf.pl so it does all this correctly, but -this has not been done yet. - -One last warning. Because locking overheads are actually quite large, the -statistics collected against the SSL_CTX for successfull connections etc -are not locked when updated. This does make it possible for these -values to be slightly lower than they should be, if you are -running multithreaded on a multi-processor box, but this does not really -matter much. - - -==== txt_db.doc ======================================================== - -TXT_DB, a simple text based in memory database. - -It holds rows of ascii data, for which the only special character is '\0'. -The rows can be of an unlimited length. - -==== why.doc ======================================================== - -This file is more of a note for other people who wish to understand why -the build environment is the way it is :-). - -The include files 'depend' as follows. -Each of -crypto/*/*.c includes crypto/cryptlib.h -ssl/*.c include ssl/ssl_locl.h -apps/*.c include apps/apps.h -crypto/cryptlib.h, ssl/ssl_locl.h and apps/apps.h -all include e_os.h which contains OS/environment specific information. -If you need to add something todo with a particular environment, -add it to this file. It is worth remembering that quite a few libraries, -like lhash, des, md, sha etc etc do not include crypto/cryptlib.h. This -is because these libraries should be 'independantly compilable' and so I -try to keep them this way. -e_os.h is not so much a part of SSLeay, as the placing in one spot all the -evil OS dependant muck. - -I wanted to automate as many things as possible. This includes -error number generation. A -make errors -will scan the source files for error codes, append them to the correct -header files, and generate the functions to print the text version -of the error numbers. So don't even think about adding error numbers by -hand, put them in the form -XXXerr(XXXX_F_XXXX,YYYY_R_YYYY); -on line and it will be automatically picked up my a make errors. - -In a similar vein, programs to be added into ssleay in the apps directory -just need to have an entry added to E_EXE in makefile.ssl and -everthing will work as expected. Don't edit progs.h by hand. - -make links re-generates the symbolic links that are used. The reason why -I keep everything in its own directory, and don't put all the -test programs and header files in 'test' and 'include' is because I want -to keep the 'sub-libraries' independant. I still 'pull' out -indervidual libraries for use in specific projects where the code is -required. I have used the 'lhash' library in just about every software -project I have worked on :-). - -make depend generates dependancies and -make dclean removes them. - -You will notice that I use perl quite a bit when I could be using 'sed'. -The reason I decided to do this was to just stick to one 'extra' program. -For Windows NT, I have perl and no sed. - -The util/mk1mf.pl program can be used to generate a single makefile. -I use this because makefiles under Microsoft are horrific. -Each C compiler seems to have different linker formats, which have -to be used because the retarted C compilers explode when you do -cl -o file *.o. - -Now some would argue that I should just use the single makefile. I don't -like it during develoment for 2 reasons. First, the actuall make -command takes a long time. For my current setup, if I'm in -crypto/bn and I type make, only the crypto/bn directory gets rebuilt, -which is nice when you are modifying prototypes in bn.h which -half the SSLeay depends on. The second is that to add a new souce file -I just plonk it in at the required spot in the local makefile. This -then alows me to keep things local, I don't need to modify a 'global' -tables (the make for unix, the make for NT, the make for w31...). -When I am ripping apart a library structure, it is nice to only -have to worry about one directory :-). - -Having said all this, for the hell of it I put together 2 files that -#include all the souce code (generated by doing a ls */*.o after a build). -crypto.c takes only 30 seconds to build under NT and 2 minutes under linux -for my pentium100. Much faster that the normal build :-). -Again, the problem is that when using libraries, every program linked -to libcrypto.a would suddenly get 330k of library when it may only need -1k. This technique does look like a nice way to do shared libraries though. - -Oh yes, as a final note, to 'build' a distribution, I just type -make dist. -This cleans and packages everything. The directory needs to be called -SSLeay since the make does a 'cd ..' and renames and tars things up. - -==== req.1 ======================================================== - -The 'req' command is used to manipulate and deal with pkcs#10 -certificate requests. - -It's default mode of operation is to load a certificate and then -write it out again. - -By default the 'req' is read from stdin in 'PEM' format. -The -inform option can be used to specify 'pem' format or 'der' -format. PEM format is the base64 encoding of the DER format. - -By default 'req' then writes the request back out. -outform can be used -to indicate the desired output format, be it 'pem' or 'der'. - -To specify an input file, use the '-in' option and the '-out' option -can be used to specify the output file. - -If you wish to perform a command and not output the certificate -request afterwards, use the '-noout' option. - -When a certificate is loaded, it can be printed in a human readable -ascii format via the '-text' option. - -To check that the signature on a certificate request is correct, use -the '-verify' option to make sure that the private key contained in the -certificate request corresponds to the signature. - -Besides the default mode, there is also the 'generate a certificate -request' mode. There are several flags that trigger this mode. - --new will generate a new RSA key (if required) and then prompts -the user for details for the certificate request. --newkey has an argument that is the number of bits to make the new -key. This function also triggers '-new'. - -The '-new' option can have a key to use specified instead of having to -load one, '-key' is used to specify the file containg the key. --keyform can be used to specify the format of the key. Only -'pem' and 'der' formats are supported, later, 'netscape' format may be added. - -Finally there is the '-x509' options which makes req output a self -signed x509 certificate instead of a certificate request. - -Now as you may have noticed, there are lots of default options that -cannot be specified via the command line. They are held in a 'template' -or 'configuration file'. The -config option specifies which configuration -file to use. See conf.doc for details on the syntax of this file. - -The req command uses the 'req' section of the config file. - ---- -# The following variables are defined. For this example I will populate -# the various values -[ req ] -default_bits = 512 # default number of bits to use. -default_keyfile = testkey.pem # Where to write the generated keyfile - # if not specified. -distinguished_name= req_dn # The section that contains the - # information about which 'object' we - # want to put in the DN. -attributes = req_attr # The objects we want for the - # attributes field. -encrypt_rsa_key = no # Should we encrypt newly generated - # keys. I strongly recommend 'yes'. - -# The distinguished name section. For the following entries, the -# object names must exist in the SSLeay header file objects.h. If they -# do not, they will be silently ignored. The entries have the following -# format. -# <object_name> => string to prompt with -# <object_name>_default => default value for people -# <object_name>_value => Automatically use this value for this field. -# <object_name>_min => minimum number of characters for data (def. 0) -# <object_name>_max => maximum number of characters for data (def. inf.) -# All of these entries are optional except for the first one. -[ req_dn ] -countryName = Country Name (2 letter code) -countryName_default = AU - -stateOrProvinceName = State or Province Name (full name) -stateOrProvinceName_default = Queensland - -localityName = Locality Name (eg, city) - -organizationName = Organization Name (eg, company) -organizationName_default = Mincom Pty Ltd - -organizationalUnitName = Organizational Unit Name (eg, section) -organizationalUnitName_default = MTR - -commonName = Common Name (eg, YOUR name) -commonName_max = 64 - -emailAddress = Email Address -emailAddress_max = 40 - -# The next section is the attributes section. This is exactly the -# same as for the previous section except that the resulting objects are -# put in the attributes field. -[ req_attr ] -challengePassword = A challenge password -challengePassword_min = 4 -challengePassword_max = 20 - -unstructuredName = An optional company name - ----- -Also note that the order that attributes appear in this file is the -order they will be put into the distinguished name. - -Once this request has been generated, it can be sent to a CA for -certifying. - ----- -A few quick examples.... - -To generate a new request and a new key -req -new - -To generate a new request and a 1058 bit key -req -newkey 1058 - -To generate a new request using a pre-existing key -req -new -key key.pem - -To generate a self signed x509 certificate from a certificate -request using a supplied key, and we want to see the text form of the -output certificate (which we will put in the file selfSign.pem -req -x509 -in req.pem -key key.pem -text -out selfSign.pem - -Verify that the signature is correct on a certificate request. -req -verify -in req.pem - -Verify that the signature was made using a specified public key. -req -verify -in req.pem -key key.pem - -Print the contents of a certificate request -req -text -in req.pem - -==== danger ======================================================== - -If you specify a SSLv2 cipher, and the mode is SSLv23 and the server -can talk SSLv3, it will claim there is no cipher since you should be -using SSLv3. - -When tracing debug stuff, remember BIO_s_socket() is different to -BIO_s_connect(). - -BSD/OS assember is not working - |