diff options
Diffstat (limited to 'Utilities/cmcurl/lib/smtp.c')
| -rw-r--r-- | Utilities/cmcurl/lib/smtp.c | 1645 |
1 files changed, 1645 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/smtp.c b/Utilities/cmcurl/lib/smtp.c new file mode 100644 index 0000000..3f3b45a --- /dev/null +++ b/Utilities/cmcurl/lib/smtp.c @@ -0,0 +1,1645 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 1998 - 2018, Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at https://curl.haxx.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + * RFC1870 SMTP Service Extension for Message Size + * RFC2195 CRAM-MD5 authentication + * RFC2831 DIGEST-MD5 authentication + * RFC3207 SMTP over TLS + * RFC4422 Simple Authentication and Security Layer (SASL) + * RFC4616 PLAIN authentication + * RFC4752 The Kerberos V5 ("GSSAPI") SASL Mechanism + * RFC4954 SMTP Authentication + * RFC5321 SMTP protocol + * RFC6749 OAuth 2.0 Authorization Framework + * Draft SMTP URL Interface <draft-earhart-url-smtp-00.txt> + * Draft LOGIN SASL Mechanism <draft-murchison-sasl-login-00.txt> + * + ***************************************************************************/ + +#include "curl_setup.h" + +#ifndef CURL_DISABLE_SMTP + +#ifdef HAVE_NETINET_IN_H +#include <netinet/in.h> +#endif +#ifdef HAVE_ARPA_INET_H +#include <arpa/inet.h> +#endif +#ifdef HAVE_UTSNAME_H +#include <sys/utsname.h> +#endif +#ifdef HAVE_NETDB_H +#include <netdb.h> +#endif +#ifdef __VMS +#include <in.h> +#include <inet.h> +#endif + +#if (defined(NETWARE) && defined(__NOVELL_LIBC__)) +#undef in_addr_t +#define in_addr_t unsigned long +#endif + +#include <curl/curl.h> +#include "urldata.h" +#include "sendf.h" +#include "hostip.h" +#include "progress.h" +#include "transfer.h" +#include "escape.h" +#include "http.h" /* for HTTP proxy tunnel stuff */ +#include "mime.h" +#include "socks.h" +#include "smtp.h" +#include "strtoofft.h" +#include "strcase.h" +#include "vtls/vtls.h" +#include "connect.h" +#include "strerror.h" +#include "select.h" +#include "multiif.h" +#include "url.h" +#include "curl_gethostname.h" +#include "curl_sasl.h" +#include "warnless.h" +/* The last 3 #include files should be in this order */ +#include "curl_printf.h" +#include "curl_memory.h" +#include "memdebug.h" + +/* Local API functions */ +static CURLcode smtp_regular_transfer(struct connectdata *conn, bool *done); +static CURLcode smtp_do(struct connectdata *conn, bool *done); +static CURLcode smtp_done(struct connectdata *conn, CURLcode status, + bool premature); +static CURLcode smtp_connect(struct connectdata *conn, bool *done); +static CURLcode smtp_disconnect(struct connectdata *conn, bool dead); +static CURLcode smtp_multi_statemach(struct connectdata *conn, bool *done); +static int smtp_getsock(struct connectdata *conn, curl_socket_t *socks, + int numsocks); +static CURLcode smtp_doing(struct connectdata *conn, bool *dophase_done); +static CURLcode smtp_setup_connection(struct connectdata *conn); +static CURLcode smtp_parse_url_options(struct connectdata *conn); +static CURLcode smtp_parse_url_path(struct connectdata *conn); +static CURLcode smtp_parse_custom_request(struct connectdata *conn); +static CURLcode smtp_perform_auth(struct connectdata *conn, const char *mech, + const char *initresp); +static CURLcode smtp_continue_auth(struct connectdata *conn, const char *resp); +static void smtp_get_message(char *buffer, char **outptr); + +/* + * SMTP protocol handler. + */ + +const struct Curl_handler Curl_handler_smtp = { + "SMTP", /* scheme */ + smtp_setup_connection, /* setup_connection */ + smtp_do, /* do_it */ + smtp_done, /* done */ + ZERO_NULL, /* do_more */ + smtp_connect, /* connect_it */ + smtp_multi_statemach, /* connecting */ + smtp_doing, /* doing */ + smtp_getsock, /* proto_getsock */ + smtp_getsock, /* doing_getsock */ + ZERO_NULL, /* domore_getsock */ + ZERO_NULL, /* perform_getsock */ + smtp_disconnect, /* disconnect */ + ZERO_NULL, /* readwrite */ + ZERO_NULL, /* connection_check */ + PORT_SMTP, /* defport */ + CURLPROTO_SMTP, /* protocol */ + PROTOPT_CLOSEACTION | PROTOPT_NOURLQUERY | /* flags */ + PROTOPT_URLOPTIONS +}; + +#ifdef USE_SSL +/* + * SMTPS protocol handler. + */ + +const struct Curl_handler Curl_handler_smtps = { + "SMTPS", /* scheme */ + smtp_setup_connection, /* setup_connection */ + smtp_do, /* do_it */ + smtp_done, /* done */ + ZERO_NULL, /* do_more */ + smtp_connect, /* connect_it */ + smtp_multi_statemach, /* connecting */ + smtp_doing, /* doing */ + smtp_getsock, /* proto_getsock */ + smtp_getsock, /* doing_getsock */ + ZERO_NULL, /* domore_getsock */ + ZERO_NULL, /* perform_getsock */ + smtp_disconnect, /* disconnect */ + ZERO_NULL, /* readwrite */ + ZERO_NULL, /* connection_check */ + PORT_SMTPS, /* defport */ + CURLPROTO_SMTPS, /* protocol */ + PROTOPT_CLOSEACTION | PROTOPT_SSL + | PROTOPT_NOURLQUERY | PROTOPT_URLOPTIONS /* flags */ +}; +#endif + +/* SASL parameters for the smtp protocol */ +static const struct SASLproto saslsmtp = { + "smtp", /* The service name */ + 334, /* Code received when continuation is expected */ + 235, /* Code to receive upon authentication success */ + 512 - 8, /* Maximum initial response length (no max) */ + smtp_perform_auth, /* Send authentication command */ + smtp_continue_auth, /* Send authentication continuation */ + smtp_get_message /* Get SASL response message */ +}; + +#ifdef USE_SSL +static void smtp_to_smtps(struct connectdata *conn) +{ + /* Change the connection handler */ + conn->handler = &Curl_handler_smtps; + + /* Set the connection's upgraded to TLS flag */ + conn->tls_upgraded = TRUE; +} +#else +#define smtp_to_smtps(x) Curl_nop_stmt +#endif + +/*********************************************************************** + * + * smtp_endofresp() + * + * Checks for an ending SMTP status code at the start of the given string, but + * also detects various capabilities from the EHLO response including the + * supported authentication mechanisms. + */ +static bool smtp_endofresp(struct connectdata *conn, char *line, size_t len, + int *resp) +{ + struct smtp_conn *smtpc = &conn->proto.smtpc; + bool result = FALSE; + + /* Nothing for us */ + if(len < 4 || !ISDIGIT(line[0]) || !ISDIGIT(line[1]) || !ISDIGIT(line[2])) + return FALSE; + + /* Do we have a command response? This should be the response code followed + by a space and optionally some text as per RFC-5321 and as outlined in + Section 4. Examples of RFC-4954 but some e-mail servers ignore this and + only send the response code instead as per Section 4.2. */ + if(line[3] == ' ' || len == 5) { + result = TRUE; + *resp = curlx_sltosi(strtol(line, NULL, 10)); + + /* Make sure real server never sends internal value */ + if(*resp == 1) + *resp = 0; + } + /* Do we have a multiline (continuation) response? */ + else if(line[3] == '-' && + (smtpc->state == SMTP_EHLO || smtpc->state == SMTP_COMMAND)) { + result = TRUE; + *resp = 1; /* Internal response code */ + } + + return result; +} + +/*********************************************************************** + * + * smtp_get_message() + * + * Gets the authentication message from the response buffer. + */ +static void smtp_get_message(char *buffer, char **outptr) +{ + size_t len = strlen(buffer); + char *message = NULL; + + if(len > 4) { + /* Find the start of the message */ + len -= 4; + for(message = buffer + 4; *message == ' ' || *message == '\t'; + message++, len--) + ; + + /* Find the end of the message */ + for(; len--;) + if(message[len] != '\r' && message[len] != '\n' && message[len] != ' ' && + message[len] != '\t') + break; + + /* Terminate the message */ + if(++len) { + message[len] = '\0'; + } + } + else + /* junk input => zero length output */ + message = &buffer[len]; + + *outptr = message; +} + +/*********************************************************************** + * + * state() + * + * This is the ONLY way to change SMTP state! + */ +static void state(struct connectdata *conn, smtpstate newstate) +{ + struct smtp_conn *smtpc = &conn->proto.smtpc; +#if defined(DEBUGBUILD) && !defined(CURL_DISABLE_VERBOSE_STRINGS) + /* for debug purposes */ + static const char * const names[] = { + "STOP", + "SERVERGREET", + "EHLO", + "HELO", + "STARTTLS", + "UPGRADETLS", + "AUTH", + "COMMAND", + "MAIL", + "RCPT", + "DATA", + "POSTDATA", + "QUIT", + /* LAST */ + }; + + if(smtpc->state != newstate) + infof(conn->data, "SMTP %p state change from %s to %s\n", + (void *)smtpc, names[smtpc->state], names[newstate]); +#endif + + smtpc->state = newstate; +} + +/*********************************************************************** + * + * smtp_perform_ehlo() + * + * Sends the EHLO command to not only initialise communication with the ESMTP + * server but to also obtain a list of server side supported capabilities. + */ +static CURLcode smtp_perform_ehlo(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + smtpc->sasl.authmechs = SASL_AUTH_NONE; /* No known auth. mechanism yet */ + smtpc->sasl.authused = SASL_AUTH_NONE; /* Clear the authentication mechanism + used for esmtp connections */ + smtpc->tls_supported = FALSE; /* Clear the TLS capability */ + smtpc->auth_supported = FALSE; /* Clear the AUTH capability */ + + /* Send the EHLO command */ + result = Curl_pp_sendf(&smtpc->pp, "EHLO %s", smtpc->domain); + + if(!result) + state(conn, SMTP_EHLO); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_helo() + * + * Sends the HELO command to initialise communication with the SMTP server. + */ +static CURLcode smtp_perform_helo(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + smtpc->sasl.authused = SASL_AUTH_NONE; /* No authentication mechanism used + in smtp connections */ + + /* Send the HELO command */ + result = Curl_pp_sendf(&smtpc->pp, "HELO %s", smtpc->domain); + + if(!result) + state(conn, SMTP_HELO); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_starttls() + * + * Sends the STLS command to start the upgrade to TLS. + */ +static CURLcode smtp_perform_starttls(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + + /* Send the STARTTLS command */ + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "%s", "STARTTLS"); + + if(!result) + state(conn, SMTP_STARTTLS); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_upgrade_tls() + * + * Performs the upgrade to TLS. + */ +static CURLcode smtp_perform_upgrade_tls(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + /* Start the SSL connection */ + result = Curl_ssl_connect_nonblocking(conn, FIRSTSOCKET, &smtpc->ssldone); + + if(!result) { + if(smtpc->state != SMTP_UPGRADETLS) + state(conn, SMTP_UPGRADETLS); + + if(smtpc->ssldone) { + smtp_to_smtps(conn); + result = smtp_perform_ehlo(conn); + } + } + + return result; +} + +/*********************************************************************** + * + * smtp_perform_auth() + * + * Sends an AUTH command allowing the client to login with the given SASL + * authentication mechanism. + */ +static CURLcode smtp_perform_auth(struct connectdata *conn, + const char *mech, + const char *initresp) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + if(initresp) { /* AUTH <mech> ...<crlf> */ + /* Send the AUTH command with the initial response */ + result = Curl_pp_sendf(&smtpc->pp, "AUTH %s %s", mech, initresp); + } + else { + /* Send the AUTH command */ + result = Curl_pp_sendf(&smtpc->pp, "AUTH %s", mech); + } + + return result; +} + +/*********************************************************************** + * + * smtp_continue_auth() + * + * Sends SASL continuation data or cancellation. + */ +static CURLcode smtp_continue_auth(struct connectdata *conn, const char *resp) +{ + struct smtp_conn *smtpc = &conn->proto.smtpc; + + return Curl_pp_sendf(&smtpc->pp, "%s", resp); +} + +/*********************************************************************** + * + * smtp_perform_authentication() + * + * Initiates the authentication sequence, with the appropriate SASL + * authentication mechanism. + */ +static CURLcode smtp_perform_authentication(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + saslprogress progress; + + /* Check we have enough data to authenticate with, and the + server supports authentiation, and end the connect phase if not */ + if(!smtpc->auth_supported || + !Curl_sasl_can_authenticate(&smtpc->sasl, conn)) { + state(conn, SMTP_STOP); + return result; + } + + /* Calculate the SASL login details */ + result = Curl_sasl_start(&smtpc->sasl, conn, FALSE, &progress); + + if(!result) { + if(progress == SASL_INPROGRESS) + state(conn, SMTP_AUTH); + else { + /* Other mechanisms not supported */ + infof(conn->data, "No known authentication mechanisms supported!\n"); + result = CURLE_LOGIN_DENIED; + } + } + + return result; +} + +/*********************************************************************** + * + * smtp_perform_command() + * + * Sends a SMTP based command. + */ +static CURLcode smtp_perform_command(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + + /* Send the command */ + if(smtp->rcpt) + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "%s %s", + smtp->custom && smtp->custom[0] != '\0' ? + smtp->custom : "VRFY", + smtp->rcpt->data); + else + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "%s", + smtp->custom && smtp->custom[0] != '\0' ? + smtp->custom : "HELP"); + + if(!result) + state(conn, SMTP_COMMAND); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_mail() + * + * Sends an MAIL command to initiate the upload of a message. + */ +static CURLcode smtp_perform_mail(struct connectdata *conn) +{ + char *from = NULL; + char *auth = NULL; + char *size = NULL; + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + /* Calculate the FROM parameter */ + if(!data->set.str[STRING_MAIL_FROM]) + /* Null reverse-path, RFC-5321, sect. 3.6.3 */ + from = strdup("<>"); + else if(data->set.str[STRING_MAIL_FROM][0] == '<') + from = aprintf("%s", data->set.str[STRING_MAIL_FROM]); + else + from = aprintf("<%s>", data->set.str[STRING_MAIL_FROM]); + + if(!from) + return CURLE_OUT_OF_MEMORY; + + /* Calculate the optional AUTH parameter */ + if(data->set.str[STRING_MAIL_AUTH] && conn->proto.smtpc.sasl.authused) { + if(data->set.str[STRING_MAIL_AUTH][0] != '\0') + auth = aprintf("%s", data->set.str[STRING_MAIL_AUTH]); + else + /* Empty AUTH, RFC-2554, sect. 5 */ + auth = strdup("<>"); + + if(!auth) { + free(from); + + return CURLE_OUT_OF_MEMORY; + } + } + + /* Prepare the mime data if some. */ + if(data->set.mimepost.kind != MIMEKIND_NONE) { + /* Use the whole structure as data. */ + data->set.mimepost.flags &= ~MIME_BODY_ONLY; + + /* Add external headers and mime version. */ + curl_mime_headers(&data->set.mimepost, data->set.headers, 0); + result = Curl_mime_prepare_headers(&data->set.mimepost, NULL, + NULL, MIMESTRATEGY_MAIL); + + if(!result) + if(!Curl_checkheaders(conn, "Mime-Version")) + result = Curl_mime_add_header(&data->set.mimepost.curlheaders, + "Mime-Version: 1.0"); + + /* Make sure we will read the entire mime structure. */ + if(!result) + result = Curl_mime_rewind(&data->set.mimepost); + + if(result) { + free(from); + free(auth); + return result; + } + + data->state.infilesize = Curl_mime_size(&data->set.mimepost); + + /* Read from mime structure. */ + data->state.fread_func = (curl_read_callback) Curl_mime_read; + data->state.in = (void *) &data->set.mimepost; + } + + /* Calculate the optional SIZE parameter */ + if(conn->proto.smtpc.size_supported && data->state.infilesize > 0) { + size = aprintf("%" CURL_FORMAT_CURL_OFF_T, data->state.infilesize); + + if(!size) { + free(from); + free(auth); + + return CURLE_OUT_OF_MEMORY; + } + } + + /* Send the MAIL command */ + if(!auth && !size) + result = Curl_pp_sendf(&conn->proto.smtpc.pp, + "MAIL FROM:%s", from); + else if(auth && !size) + result = Curl_pp_sendf(&conn->proto.smtpc.pp, + "MAIL FROM:%s AUTH=%s", from, auth); + else if(auth && size) + result = Curl_pp_sendf(&conn->proto.smtpc.pp, + "MAIL FROM:%s AUTH=%s SIZE=%s", from, auth, size); + else + result = Curl_pp_sendf(&conn->proto.smtpc.pp, + "MAIL FROM:%s SIZE=%s", from, size); + + free(from); + free(auth); + free(size); + + if(!result) + state(conn, SMTP_MAIL); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_rcpt_to() + * + * Sends a RCPT TO command for a given recipient as part of the message upload + * process. + */ +static CURLcode smtp_perform_rcpt_to(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + + /* Send the RCPT TO command */ + if(smtp->rcpt->data[0] == '<') + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "RCPT TO:%s", + smtp->rcpt->data); + else + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "RCPT TO:<%s>", + smtp->rcpt->data); + if(!result) + state(conn, SMTP_RCPT); + + return result; +} + +/*********************************************************************** + * + * smtp_perform_quit() + * + * Performs the quit action prior to sclose() being called. + */ +static CURLcode smtp_perform_quit(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + + /* Send the QUIT command */ + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "%s", "QUIT"); + + if(!result) + state(conn, SMTP_QUIT); + + return result; +} + +/* For the initial server greeting */ +static CURLcode smtp_state_servergreet_resp(struct connectdata *conn, + int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + (void)instate; /* no use for this yet */ + + if(smtpcode/100 != 2) { + failf(data, "Got unexpected smtp-server response: %d", smtpcode); + result = CURLE_WEIRD_SERVER_REPLY; + } + else + result = smtp_perform_ehlo(conn); + + return result; +} + +/* For STARTTLS responses */ +static CURLcode smtp_state_starttls_resp(struct connectdata *conn, + int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + (void)instate; /* no use for this yet */ + + if(smtpcode != 220) { + if(data->set.use_ssl != CURLUSESSL_TRY) { + failf(data, "STARTTLS denied, code %d", smtpcode); + result = CURLE_USE_SSL_FAILED; + } + else + result = smtp_perform_authentication(conn); + } + else + result = smtp_perform_upgrade_tls(conn); + + return result; +} + +/* For EHLO responses */ +static CURLcode smtp_state_ehlo_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct smtp_conn *smtpc = &conn->proto.smtpc; + const char *line = data->state.buffer; + size_t len = strlen(line); + size_t wordlen; + + (void)instate; /* no use for this yet */ + + if(smtpcode/100 != 2 && smtpcode != 1) { + if(data->set.use_ssl <= CURLUSESSL_TRY || conn->ssl[FIRSTSOCKET].use) + result = smtp_perform_helo(conn); + else { + failf(data, "Remote access denied: %d", smtpcode); + result = CURLE_REMOTE_ACCESS_DENIED; + } + } + else { + line += 4; + len -= 4; + + /* Does the server support the STARTTLS capability? */ + if(len >= 8 && !memcmp(line, "STARTTLS", 8)) + smtpc->tls_supported = TRUE; + + /* Does the server support the SIZE capability? */ + else if(len >= 4 && !memcmp(line, "SIZE", 4)) + smtpc->size_supported = TRUE; + + /* Does the server support authentication? */ + else if(len >= 5 && !memcmp(line, "AUTH ", 5)) { + smtpc->auth_supported = TRUE; + + /* Advance past the AUTH keyword */ + line += 5; + len -= 5; + + /* Loop through the data line */ + for(;;) { + size_t llen; + unsigned int mechbit; + + while(len && + (*line == ' ' || *line == '\t' || + *line == '\r' || *line == '\n')) { + + line++; + len--; + } + + if(!len) + break; + + /* Extract the word */ + for(wordlen = 0; wordlen < len && line[wordlen] != ' ' && + line[wordlen] != '\t' && line[wordlen] != '\r' && + line[wordlen] != '\n';) + wordlen++; + + /* Test the word for a matching authentication mechanism */ + mechbit = Curl_sasl_decode_mech(line, wordlen, &llen); + if(mechbit && llen == wordlen) + smtpc->sasl.authmechs |= mechbit; + + line += wordlen; + len -= wordlen; + } + } + + if(smtpcode != 1) { + if(data->set.use_ssl && !conn->ssl[FIRSTSOCKET].use) { + /* We don't have a SSL/TLS connection yet, but SSL is requested */ + if(smtpc->tls_supported) + /* Switch to TLS connection now */ + result = smtp_perform_starttls(conn); + else if(data->set.use_ssl == CURLUSESSL_TRY) + /* Fallback and carry on with authentication */ + result = smtp_perform_authentication(conn); + else { + failf(data, "STARTTLS not supported."); + result = CURLE_USE_SSL_FAILED; + } + } + else + result = smtp_perform_authentication(conn); + } + } + + return result; +} + +/* For HELO responses */ +static CURLcode smtp_state_helo_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + (void)instate; /* no use for this yet */ + + if(smtpcode/100 != 2) { + failf(data, "Remote access denied: %d", smtpcode); + result = CURLE_REMOTE_ACCESS_DENIED; + } + else + /* End of connect phase */ + state(conn, SMTP_STOP); + + return result; +} + +/* For SASL authentication responses */ +static CURLcode smtp_state_auth_resp(struct connectdata *conn, + int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct smtp_conn *smtpc = &conn->proto.smtpc; + saslprogress progress; + + (void)instate; /* no use for this yet */ + + result = Curl_sasl_continue(&smtpc->sasl, conn, smtpcode, &progress); + if(!result) + switch(progress) { + case SASL_DONE: + state(conn, SMTP_STOP); /* Authenticated */ + break; + case SASL_IDLE: /* No mechanism left after cancellation */ + failf(data, "Authentication cancelled"); + result = CURLE_LOGIN_DENIED; + break; + default: + break; + } + + return result; +} + +/* For command responses */ +static CURLcode smtp_state_command_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + char *line = data->state.buffer; + size_t len = strlen(line); + + (void)instate; /* no use for this yet */ + + if((smtp->rcpt && smtpcode/100 != 2 && smtpcode != 553 && smtpcode != 1) || + (!smtp->rcpt && smtpcode/100 != 2 && smtpcode != 1)) { + failf(data, "Command failed: %d", smtpcode); + result = CURLE_RECV_ERROR; + } + else { + /* Temporarily add the LF character back and send as body to the client */ + if(!data->set.opt_no_body) { + line[len] = '\n'; + result = Curl_client_write(conn, CLIENTWRITE_BODY, line, len + 1); + line[len] = '\0'; + } + + if(smtpcode != 1) { + if(smtp->rcpt) { + smtp->rcpt = smtp->rcpt->next; + + if(smtp->rcpt) { + /* Send the next command */ + result = smtp_perform_command(conn); + } + else + /* End of DO phase */ + state(conn, SMTP_STOP); + } + else + /* End of DO phase */ + state(conn, SMTP_STOP); + } + } + + return result; +} + +/* For MAIL responses */ +static CURLcode smtp_state_mail_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + (void)instate; /* no use for this yet */ + + if(smtpcode/100 != 2) { + failf(data, "MAIL failed: %d", smtpcode); + result = CURLE_SEND_ERROR; + } + else + /* Start the RCPT TO command */ + result = smtp_perform_rcpt_to(conn); + + return result; +} + +/* For RCPT responses */ +static CURLcode smtp_state_rcpt_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + + (void)instate; /* no use for this yet */ + + if(smtpcode/100 != 2) { + failf(data, "RCPT failed: %d", smtpcode); + result = CURLE_SEND_ERROR; + } + else { + smtp->rcpt = smtp->rcpt->next; + + if(smtp->rcpt) + /* Send the next RCPT TO command */ + result = smtp_perform_rcpt_to(conn); + else { + /* Send the DATA command */ + result = Curl_pp_sendf(&conn->proto.smtpc.pp, "%s", "DATA"); + + if(!result) + state(conn, SMTP_DATA); + } + } + + return result; +} + +/* For DATA response */ +static CURLcode smtp_state_data_resp(struct connectdata *conn, int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + + (void)instate; /* no use for this yet */ + + if(smtpcode != 354) { + failf(data, "DATA failed: %d", smtpcode); + result = CURLE_SEND_ERROR; + } + else { + /* Set the progress upload size */ + Curl_pgrsSetUploadSize(data, data->state.infilesize); + + /* SMTP upload */ + Curl_setup_transfer(conn, -1, -1, FALSE, NULL, FIRSTSOCKET, NULL); + + /* End of DO phase */ + state(conn, SMTP_STOP); + } + + return result; +} + +/* For POSTDATA responses, which are received after the entire DATA + part has been sent to the server */ +static CURLcode smtp_state_postdata_resp(struct connectdata *conn, + int smtpcode, + smtpstate instate) +{ + CURLcode result = CURLE_OK; + + (void)instate; /* no use for this yet */ + + if(smtpcode != 250) + result = CURLE_RECV_ERROR; + + /* End of DONE phase */ + state(conn, SMTP_STOP); + + return result; +} + +static CURLcode smtp_statemach_act(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + curl_socket_t sock = conn->sock[FIRSTSOCKET]; + struct Curl_easy *data = conn->data; + int smtpcode; + struct smtp_conn *smtpc = &conn->proto.smtpc; + struct pingpong *pp = &smtpc->pp; + size_t nread = 0; + + /* Busy upgrading the connection; right now all I/O is SSL/TLS, not SMTP */ + if(smtpc->state == SMTP_UPGRADETLS) + return smtp_perform_upgrade_tls(conn); + + /* Flush any data that needs to be sent */ + if(pp->sendleft) + return Curl_pp_flushsend(pp); + + do { + /* Read the response from the server */ + result = Curl_pp_readresp(sock, pp, &smtpcode, &nread); + if(result) + return result; + + /* Store the latest response for later retrieval if necessary */ + if(smtpc->state != SMTP_QUIT && smtpcode != 1) + data->info.httpcode = smtpcode; + + if(!smtpcode) + break; + + /* We have now received a full SMTP server response */ + switch(smtpc->state) { + case SMTP_SERVERGREET: + result = smtp_state_servergreet_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_EHLO: + result = smtp_state_ehlo_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_HELO: + result = smtp_state_helo_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_STARTTLS: + result = smtp_state_starttls_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_AUTH: + result = smtp_state_auth_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_COMMAND: + result = smtp_state_command_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_MAIL: + result = smtp_state_mail_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_RCPT: + result = smtp_state_rcpt_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_DATA: + result = smtp_state_data_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_POSTDATA: + result = smtp_state_postdata_resp(conn, smtpcode, smtpc->state); + break; + + case SMTP_QUIT: + /* fallthrough, just stop! */ + default: + /* internal error */ + state(conn, SMTP_STOP); + break; + } + } while(!result && smtpc->state != SMTP_STOP && Curl_pp_moredata(pp)); + + return result; +} + +/* Called repeatedly until done from multi.c */ +static CURLcode smtp_multi_statemach(struct connectdata *conn, bool *done) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + if((conn->handler->flags & PROTOPT_SSL) && !smtpc->ssldone) { + result = Curl_ssl_connect_nonblocking(conn, FIRSTSOCKET, &smtpc->ssldone); + if(result || !smtpc->ssldone) + return result; + } + + result = Curl_pp_statemach(&smtpc->pp, FALSE); + *done = (smtpc->state == SMTP_STOP) ? TRUE : FALSE; + + return result; +} + +static CURLcode smtp_block_statemach(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + + while(smtpc->state != SMTP_STOP && !result) + result = Curl_pp_statemach(&smtpc->pp, TRUE); + + return result; +} + +/* Allocate and initialize the SMTP struct for the current Curl_easy if + required */ +static CURLcode smtp_init(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp; + + smtp = data->req.protop = calloc(sizeof(struct SMTP), 1); + if(!smtp) + result = CURLE_OUT_OF_MEMORY; + + return result; +} + +/* For the SMTP "protocol connect" and "doing" phases only */ +static int smtp_getsock(struct connectdata *conn, curl_socket_t *socks, + int numsocks) +{ + return Curl_pp_getsock(&conn->proto.smtpc.pp, socks, numsocks); +} + +/*********************************************************************** + * + * smtp_connect() + * + * This function should do everything that is to be considered a part of + * the connection phase. + * + * The variable pointed to by 'done' will be TRUE if the protocol-layer + * connect phase is done when this function returns, or FALSE if not. + */ +static CURLcode smtp_connect(struct connectdata *conn, bool *done) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + struct pingpong *pp = &smtpc->pp; + + *done = FALSE; /* default to not done yet */ + + /* We always support persistent connections in SMTP */ + connkeep(conn, "SMTP default"); + + /* Set the default response time-out */ + pp->response_time = RESP_TIMEOUT; + pp->statemach_act = smtp_statemach_act; + pp->endofresp = smtp_endofresp; + pp->conn = conn; + + /* Initialize the SASL storage */ + Curl_sasl_init(&smtpc->sasl, &saslsmtp); + + /* Initialise the pingpong layer */ + Curl_pp_init(pp); + + /* Parse the URL options */ + result = smtp_parse_url_options(conn); + if(result) + return result; + + /* Parse the URL path */ + result = smtp_parse_url_path(conn); + if(result) + return result; + + /* Start off waiting for the server greeting response */ + state(conn, SMTP_SERVERGREET); + + result = smtp_multi_statemach(conn, done); + + return result; +} + +/*********************************************************************** + * + * smtp_done() + * + * The DONE function. This does what needs to be done after a single DO has + * performed. + * + * Input argument is already checked for validity. + */ +static CURLcode smtp_done(struct connectdata *conn, CURLcode status, + bool premature) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + struct pingpong *pp = &conn->proto.smtpc.pp; + char *eob; + ssize_t len; + ssize_t bytes_written; + + (void)premature; + + if(!smtp || !pp->conn) + return CURLE_OK; + + /* Cleanup our per-request based variables */ + Curl_safefree(smtp->custom); + + if(status) { + connclose(conn, "SMTP done with bad status"); /* marked for closure */ + result = status; /* use the already set error code */ + } + else if(!data->set.connect_only && data->set.mail_rcpt && + (data->set.upload || data->set.mimepost.kind)) { + /* Calculate the EOB taking into account any terminating CRLF from the + previous line of the email or the CRLF of the DATA command when there + is "no mail data". RFC-5321, sect. 4.1.1.4. + + Note: As some SSL backends, such as OpenSSL, will cause Curl_write() to + fail when using a different pointer following a previous write, that + returned CURLE_AGAIN, we duplicate the EOB now rather than when the + bytes written doesn't equal len. */ + if(smtp->trailing_crlf || !conn->data->state.infilesize) { + eob = strdup(SMTP_EOB + 2); + len = SMTP_EOB_LEN - 2; + } + else { + eob = strdup(SMTP_EOB); + len = SMTP_EOB_LEN; + } + + if(!eob) + return CURLE_OUT_OF_MEMORY; + + /* Send the end of block data */ + result = Curl_write(conn, conn->writesockfd, eob, len, &bytes_written); + if(result) { + free(eob); + return result; + } + + if(bytes_written != len) { + /* The whole chunk was not sent so keep it around and adjust the + pingpong structure accordingly */ + pp->sendthis = eob; + pp->sendsize = len; + pp->sendleft = len - bytes_written; + } + else { + /* Successfully sent so adjust the response timeout relative to now */ + pp->response = Curl_now(); + + free(eob); + } + + state(conn, SMTP_POSTDATA); + + /* Run the state-machine + + TODO: when the multi interface is used, this _really_ should be using + the smtp_multi_statemach function but we have no general support for + non-blocking DONE operations! + */ + result = smtp_block_statemach(conn); + } + + /* Clear the transfer mode for the next request */ + smtp->transfer = FTPTRANSFER_BODY; + + return result; +} + +/*********************************************************************** + * + * smtp_perform() + * + * This is the actual DO function for SMTP. Transfer a mail, send a command + * or get some data according to the options previously setup. + */ +static CURLcode smtp_perform(struct connectdata *conn, bool *connected, + bool *dophase_done) +{ + /* This is SMTP and no proxy */ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + + DEBUGF(infof(conn->data, "DO phase starts\n")); + + if(data->set.opt_no_body) { + /* Requested no body means no transfer */ + smtp->transfer = FTPTRANSFER_INFO; + } + + *dophase_done = FALSE; /* not done yet */ + + /* Store the first recipient (or NULL if not specified) */ + smtp->rcpt = data->set.mail_rcpt; + + /* Initial data character is the first character in line: it is implicitly + preceded by a virtual CRLF. */ + smtp->trailing_crlf = TRUE; + smtp->eob = 2; + + /* Start the first command in the DO phase */ + if((data->set.upload || data->set.mimepost.kind) && data->set.mail_rcpt) + /* MAIL transfer */ + result = smtp_perform_mail(conn); + else + /* SMTP based command (VRFY, EXPN, NOOP, RSET or HELP) */ + result = smtp_perform_command(conn); + + if(result) + return result; + + /* Run the state-machine */ + result = smtp_multi_statemach(conn, dophase_done); + + *connected = conn->bits.tcpconnect[FIRSTSOCKET]; + + if(*dophase_done) + DEBUGF(infof(conn->data, "DO phase is complete\n")); + + return result; +} + +/*********************************************************************** + * + * smtp_do() + * + * This function is registered as 'curl_do' function. It decodes the path + * parts etc as a wrapper to the actual DO function (smtp_perform). + * + * The input argument is already checked for validity. + */ +static CURLcode smtp_do(struct connectdata *conn, bool *done) +{ + CURLcode result = CURLE_OK; + + *done = FALSE; /* default to false */ + + /* Parse the custom request */ + result = smtp_parse_custom_request(conn); + if(result) + return result; + + result = smtp_regular_transfer(conn, done); + + return result; +} + +/*********************************************************************** + * + * smtp_disconnect() + * + * Disconnect from an SMTP server. Cleanup protocol-specific per-connection + * resources. BLOCKING. + */ +static CURLcode smtp_disconnect(struct connectdata *conn, bool dead_connection) +{ + struct smtp_conn *smtpc = &conn->proto.smtpc; + + /* We cannot send quit unconditionally. If this connection is stale or + bad in any way, sending quit and waiting around here will make the + disconnect wait in vain and cause more problems than we need to. */ + + /* The SMTP session may or may not have been allocated/setup at this + point! */ + if(!dead_connection && smtpc->pp.conn && smtpc->pp.conn->bits.protoconnstart) + if(!smtp_perform_quit(conn)) + (void)smtp_block_statemach(conn); /* ignore errors on QUIT */ + + /* Disconnect from the server */ + Curl_pp_disconnect(&smtpc->pp); + + /* Cleanup the SASL module */ + Curl_sasl_cleanup(conn, smtpc->sasl.authused); + + /* Cleanup our connection based variables */ + Curl_safefree(smtpc->domain); + + return CURLE_OK; +} + +/* Call this when the DO phase has completed */ +static CURLcode smtp_dophase_done(struct connectdata *conn, bool connected) +{ + struct SMTP *smtp = conn->data->req.protop; + + (void)connected; + + if(smtp->transfer != FTPTRANSFER_BODY) + /* no data to transfer */ + Curl_setup_transfer(conn, -1, -1, FALSE, NULL, -1, NULL); + + return CURLE_OK; +} + +/* Called from multi.c while DOing */ +static CURLcode smtp_doing(struct connectdata *conn, bool *dophase_done) +{ + CURLcode result = smtp_multi_statemach(conn, dophase_done); + + if(result) + DEBUGF(infof(conn->data, "DO phase failed\n")); + else if(*dophase_done) { + result = smtp_dophase_done(conn, FALSE /* not connected */); + + DEBUGF(infof(conn->data, "DO phase is complete\n")); + } + + return result; +} + +/*********************************************************************** + * + * smtp_regular_transfer() + * + * The input argument is already checked for validity. + * + * Performs all commands done before a regular transfer between a local and a + * remote host. + */ +static CURLcode smtp_regular_transfer(struct connectdata *conn, + bool *dophase_done) +{ + CURLcode result = CURLE_OK; + bool connected = FALSE; + struct Curl_easy *data = conn->data; + + /* Make sure size is unknown at this point */ + data->req.size = -1; + + /* Set the progress data */ + Curl_pgrsSetUploadCounter(data, 0); + Curl_pgrsSetDownloadCounter(data, 0); + Curl_pgrsSetUploadSize(data, -1); + Curl_pgrsSetDownloadSize(data, -1); + + /* Carry out the perform */ + result = smtp_perform(conn, &connected, dophase_done); + + /* Perform post DO phase operations if necessary */ + if(!result && *dophase_done) + result = smtp_dophase_done(conn, connected); + + return result; +} + +static CURLcode smtp_setup_connection(struct connectdata *conn) +{ + struct Curl_easy *data = conn->data; + CURLcode result; + + /* Clear the TLS upgraded flag */ + conn->tls_upgraded = FALSE; + + /* Initialise the SMTP layer */ + result = smtp_init(conn); + if(result) + return result; + + data->state.path++; /* don't include the initial slash */ + + return CURLE_OK; +} + +/*********************************************************************** + * + * smtp_parse_url_options() + * + * Parse the URL login options. + */ +static CURLcode smtp_parse_url_options(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct smtp_conn *smtpc = &conn->proto.smtpc; + const char *ptr = conn->options; + + smtpc->sasl.resetprefs = TRUE; + + while(!result && ptr && *ptr) { + const char *key = ptr; + const char *value; + + while(*ptr && *ptr != '=') + ptr++; + + value = ptr + 1; + + while(*ptr && *ptr != ';') + ptr++; + + if(strncasecompare(key, "AUTH=", 5)) + result = Curl_sasl_parse_url_auth_option(&smtpc->sasl, + value, ptr - value); + else + result = CURLE_URL_MALFORMAT; + + if(*ptr == ';') + ptr++; + } + + return result; +} + +/*********************************************************************** + * + * smtp_parse_url_path() + * + * Parse the URL path into separate path components. + */ +static CURLcode smtp_parse_url_path(struct connectdata *conn) +{ + /* The SMTP struct is already initialised in smtp_connect() */ + struct Curl_easy *data = conn->data; + struct smtp_conn *smtpc = &conn->proto.smtpc; + const char *path = data->state.path; + char localhost[HOSTNAME_MAX + 1]; + + /* Calculate the path if necessary */ + if(!*path) { + if(!Curl_gethostname(localhost, sizeof(localhost))) + path = localhost; + else + path = "localhost"; + } + + /* URL decode the path and use it as the domain in our EHLO */ + return Curl_urldecode(conn->data, path, 0, &smtpc->domain, NULL, TRUE); +} + +/*********************************************************************** + * + * smtp_parse_custom_request() + * + * Parse the custom request. + */ +static CURLcode smtp_parse_custom_request(struct connectdata *conn) +{ + CURLcode result = CURLE_OK; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + const char *custom = data->set.str[STRING_CUSTOMREQUEST]; + + /* URL decode the custom request */ + if(custom) + result = Curl_urldecode(data, custom, 0, &smtp->custom, NULL, TRUE); + + return result; +} + +CURLcode Curl_smtp_escape_eob(struct connectdata *conn, const ssize_t nread) +{ + /* When sending a SMTP payload we must detect CRLF. sequences making sure + they are sent as CRLF.. instead, as a . on the beginning of a line will + be deleted by the server when not part of an EOB terminator and a + genuine CRLF.CRLF which isn't escaped will wrongly be detected as end of + data by the server + */ + ssize_t i; + ssize_t si; + struct Curl_easy *data = conn->data; + struct SMTP *smtp = data->req.protop; + char *scratch = data->state.scratch; + char *newscratch = NULL; + char *oldscratch = NULL; + size_t eob_sent; + + /* Do we need to allocate a scratch buffer? */ + if(!scratch || data->set.crlf) { + oldscratch = scratch; + + scratch = newscratch = malloc(2 * data->set.buffer_size); + if(!newscratch) { + failf(data, "Failed to alloc scratch buffer!"); + + return CURLE_OUT_OF_MEMORY; + } + } + + /* Have we already sent part of the EOB? */ + eob_sent = smtp->eob; + + /* This loop can be improved by some kind of Boyer-Moore style of + approach but that is saved for later... */ + for(i = 0, si = 0; i < nread; i++) { + if(SMTP_EOB[smtp->eob] == data->req.upload_fromhere[i]) { + smtp->eob++; + + /* Is the EOB potentially the terminating CRLF? */ + if(2 == smtp->eob || SMTP_EOB_LEN == smtp->eob) + smtp->trailing_crlf = TRUE; + else + smtp->trailing_crlf = FALSE; + } + else if(smtp->eob) { + /* A previous substring matched so output that first */ + memcpy(&scratch[si], &SMTP_EOB[eob_sent], smtp->eob - eob_sent); + si += smtp->eob - eob_sent; + + /* Then compare the first byte */ + if(SMTP_EOB[0] == data->req.upload_fromhere[i]) + smtp->eob = 1; + else + smtp->eob = 0; + + eob_sent = 0; + + /* Reset the trailing CRLF flag as there was more data */ + smtp->trailing_crlf = FALSE; + } + + /* Do we have a match for CRLF. as per RFC-5321, sect. 4.5.2 */ + if(SMTP_EOB_FIND_LEN == smtp->eob) { + /* Copy the replacement data to the target buffer */ + memcpy(&scratch[si], &SMTP_EOB_REPL[eob_sent], + SMTP_EOB_REPL_LEN - eob_sent); + si += SMTP_EOB_REPL_LEN - eob_sent; + smtp->eob = 0; + eob_sent = 0; + } + else if(!smtp->eob) + scratch[si++] = data->req.upload_fromhere[i]; + } + + if(smtp->eob - eob_sent) { + /* A substring matched before processing ended so output that now */ + memcpy(&scratch[si], &SMTP_EOB[eob_sent], smtp->eob - eob_sent); + si += smtp->eob - eob_sent; + } + + /* Only use the new buffer if we replaced something */ + if(si != nread) { + /* Upload from the new (replaced) buffer instead */ + data->req.upload_fromhere = scratch; + + /* Save the buffer so it can be freed later */ + data->state.scratch = scratch; + + /* Free the old scratch buffer */ + free(oldscratch); + + /* Set the new amount too */ + data->req.upload_present = si; + } + else + free(newscratch); + + return CURLE_OK; +} + +#endif /* CURL_DISABLE_SMTP */ |