diff options
Diffstat (limited to 'library')
| -rw-r--r-- | library/http/http.tcl | 296 |
1 files changed, 199 insertions, 97 deletions
diff --git a/library/http/http.tcl b/library/http/http.tcl index 655da99..c8dbe9b 100644 --- a/library/http/http.tcl +++ b/library/http/http.tcl @@ -1,30 +1,29 @@ # http.tcl -- # -# Client-side HTTP for GET, POST, and HEAD commands. -# These routines can be used in untrusted code that uses -# the Safesock security policy. These procedures use a -# callback interface to avoid using vwait, which is not +# Client-side HTTP for GET, POST, and HEAD commands. These routines can +# be used in untrusted code that uses the Safesock security policy. These +# procedures use a callback interface to avoid using vwait, which is not # defined in the safe base. # -# See the file "license.terms" for information on usage and -# redistribution of this file, and for a DISCLAIMER OF ALL WARRANTIES. +# See the file "license.terms" for information on usage and redistribution of +# this file, and for a DISCLAIMER OF ALL WARRANTIES. # -# RCS: @(#) $Id: http.tcl,v 1.53 2005/11/15 22:58:18 dgp Exp $ +# RCS: @(#) $Id: http.tcl,v 1.54 2005/11/18 13:57:53 dkf Exp $ # Rough version history: -# 1.0 Old http_get interface -# 2.0 http:: namespace and http::geturl -# 2.1 Added callbacks to handle arriving data, and timeouts -# 2.2 Added ability to fetch into a channel -# 2.3 Added SSL support, and ability to post from a channel -# This version also cleans up error cases and eliminates the -# "ioerror" status in favor of raising an error -# 2.4 Added -binary option to http::geturl and charset element -# to the state array. +# 1.0 Old http_get interface. +# 2.0 http:: namespace and http::geturl. +# 2.1 Added callbacks to handle arriving data, and timeouts. +# 2.2 Added ability to fetch into a channel. +# 2.3 Added SSL support, and ability to post from a channel. This version +# also cleans up error cases and eliminates the "ioerror" status in +# favor of raising an error +# 2.4 Added -binary option to http::geturl and charset element to the state +# array. package require Tcl 8.4 -# keep this in sync with pkgIndex.tcl -# and with the install directories in Makefiles +# Keep this in sync with pkgIndex.tcl and with the install directories +# in Makefiles package provide http 2.5.2 namespace eval http { @@ -39,12 +38,11 @@ namespace eval http { set http(-useragent) "Tcl http client package [package provide http]" proc init {} { - # Set up the map for quoting chars - # RFC3986 Section 2.3 say percent encode all except: - # "... percent-encoded octets in the ranges of ALPHA - # (%41-%5A and %61-%7A), DIGIT (%30-%39), hyphen (%2D), - # period (%2E), underscore (%5F), or tilde (%7E) should - # not be created by URI producers ..." + # Set up the map for quoting chars. RFC3986 Section 2.3 say percent + # encode all except: "... percent-encoded octets in the ranges of ALPHA + # (%41-%5A and %61-%7A), DIGIT (%30-%39), hyphen (%2D), period (%2E), + # underscore (%5F), or tilde (%7E) should not be created by URI + # producers ..." for {set i 0} {$i <= 256} {incr i} { set c [format %c $i] if {![string match {[-._~a-zA-Z0-9]} $c]} { @@ -152,9 +150,9 @@ proc http::config {args} { # Arguments: # token Connection token. # errormsg (optional) If set, forces status to error. -# skipCB (optional) If set, don't call the -command callback. This +# skipCB (optional) If set, don't call the -command callback. This # is useful when geturl wants to throw an exception instead -# of calling the callback. That way, the same error isn't +# of calling the callback. That way, the same error isn't # reported to two places. # # Side Effects: @@ -218,17 +216,16 @@ proc http::reset { token {why reset} } { # args Option value pairs. Valid options include: # -blocksize, -validate, -headers, -timeout # Results: -# Returns a token for this connection. -# This token is the name of an array that the caller should -# unset to garbage collect the state. +# Returns a token for this connection. This token is the name of an array +# that the caller should unset to garbage collect the state. proc http::geturl { url args } { variable http variable urlTypes variable defaultCharset - # Initialize the state variable, an array. We'll return the - # name of this array as the token for the transaction. + # Initialize the state variable, an array. We'll return the name of this + # array as the token for the transaction. if {![info exists http(uid)]} { set http(uid) 0 @@ -301,17 +298,118 @@ proc http::geturl { url args } { } # Validate URL, determine the server host and port, and check proxy case - # Recognize user:pass@host URLs also, although we do not do anything - # with that info yet. + # Recognize user:pass@host URLs also, although we do not do anything with + # that info yet. + + # URLs have basically four parts. + # First, before the colon, is the protocol scheme (e.g. http) + # Second, for HTTP-like protocols, is the authority + # The authority is preceded by // and lasts up to (but not including) + # the following / and it identifies up to four parts, of which only one, + # the host, is required (if an authority is present at all). All other + # parts of the authority (user name, password, port number) are optional. + # Third is the resource name, which is split into two parts at a ? + # The first part (from the single "/" up to "?") is the path, and the + # second part (from that "?" up to "#") is the query. *HOWEVER*, we do + # not need to separate them; we send the whole lot to the server. + # Fourth is the fragment identifier, which is everything after the first + # "#" in the URL. The fragment identifier MUST NOT be sent to the server + # and indeed, we don't bother to validate it (it could be an error to + # pass it in here, but it's cheap to strip). + # + # An example of a URL that has all the parts: + # http://jschmoe:xyzzy@www.bogus.net:8000/foo/bar.tml?q=foo#changes + # The "http" is the protocol, the user is "jschmoe", the password is + # "xyzzy", the host is "www.bogus.net", the port is "8000", the path is + # "/foo/bar.tml", the query is "q=foo", and the fragment is "changes". + # + # Note that the RE actually combines the user and password parts, as + # recommended in RFC 3986. Indeed, that RFC states that putting passwords + # in URLs is a Really Bad Idea, something with which I would agree utterly. + # Also note that we do not currently support IPv6 addresses. + # + # From a validation perspective, we need to ensure that the parts of the + # URL that are going to the server are correctly encoded. + + set URLmatcher {(?x) # this is _expanded_ syntax + ^ + (?: (\w+) : ) # <protocol scheme> + (?: // + (?: + ( + [^@/\#?]+ # <userinfo part of authority> + ) @ + )? + ( [^/:\#?]+ ) # <host part of authority> + (?: : (\d+) )? # <port part of authority> + )? + ( / [^\#?]* (?: \? [^\#?]* ) )? # <path> (including query) + (?: \# (.*) )? # <fragment> + $ + } - set exp {^(([^:]*)://)?([^@]+@)?([^/:]+)(:([0-9]+))?(/.*)?$} - if {![regexp -nocase $exp $url x prefix proto user host y port srvurl]} { + # Phase one: parse + if {![regexp -- $URLmatcher $url -> proto user host port srvurl]} { unset $token return -code error "Unsupported URL: $url" } + # Phase two: validate + if {$host eq ""} { + # Caller has to provide a host name; we do not have a "default host" + # that would enable us to handle relative URLs. + unset $token + return -code error "Missing host part: $url" + # Note that we don't check the hostname for validity here; if it's + # invalid, we'll simply fail to resolve it later on. + } + if {$port ne "" && $port>65535} { + unset $token + return -code error "Invalid port number: $port" + } + # The user identification and resource identification parts of the URL can + # have encoded characters in them; take care! + if {$user ne ""} { + # Check for validity according to RFC 3986, Appendix A + set validityRE {(?xi) + ^ + (?: [\w-.~!$&'()*+,;=:] | %[0-9a-f][0-9a-f] )+ + $ + } + if {![regexp -- $validityRE $user]} { + unset $token + # Provide a better error message in this error case + if {[regexp {(?i)%(?![0-9a-f][0-9a-f]).?.?} $path bad]} { + return -code error \ + "Illegal encoding character usage \"$bad\" in URL user" + } + return -code error "Illegal characters in URL user" + } + } + if {$srvurl ne ""} { + # Check for validity according to RFC 3986, Appendix A + set validityRE {(?xi) + ^ + # Path part (already must start with / character) + (?: [\w-.~!$&'()*+,;=:@/] | %[0-9a-f][0-9a-f] )* + # Query part (optional, permits ? characters) + (?: ? (?: [\w-.~!$&'()*+,;=:@/?] | %[0-9a-f][0-9a-f] )* )? + $ + } + if {![regexp -- $validityRE $srvurl]} { + unset $token + # Provide a better error message in this error case + if {[regexp {(?i)%(?![0-9a-f][0-9a-f])..} $path bad]} { + return -code error \ + "Illegal encoding character usage \"$bad\" in URL path" + } + return -code error "Illegal characters in URL path" + } + } else { + set srvurl / + } if {[string length $proto] == 0} { set proto http - set url ${proto}://$url + set url ${proto}:$url } if {![info exists urlTypes($proto)]} { unset $token @@ -323,20 +421,27 @@ proc http::geturl { url args } { if {[string length $port] == 0} { set port $defport } - if {[string length $srvurl] == 0} { - set srvurl / - } - if {[string length $proto] == 0} { - set url http://$url - } - set state(url) $url if {![catch {$http(-proxyfilter) $host} proxy]} { set phost [lindex $proxy 0] set pport [lindex $proxy 1] } - # If a timeout is specified we set up the after event - # and arrange for an asynchronous socket connection. + # OK, now reassemble into a full URL + set url ${proto}:// + if {$user ne ""} { + append url $user + append url @ + } + append url $host + if {$port != $defport} { + append url : $port + } + append url $srvurl + # Don't append the fragment! + set state(url) $url + + # If a timeout is specified we set up the after event and arrange for an + # asynchronous socket connection. if {$state(-timeout) > 0} { set state(after) [after $state(-timeout) \ @@ -346,8 +451,8 @@ proc http::geturl { url args } { set async "" } - # If we are using the proxy, we must pass in the full URL that - # includes the server name. + # If we are using the proxy, we must pass in the full URL that includes + # the server name. if {[info exists phost] && [string length $phost]} { set srvurl $url @@ -355,11 +460,11 @@ proc http::geturl { url args } { } else { set conStat [catch {eval $defcmd $async {$host $port}} s] } - if {$conStat} { - # something went wrong while trying to establish the connection - # Clean up after events and such, but DON'T call the command callback - # (if available) because we're going to throw an exception from here + if {$conStat} { + # Something went wrong while trying to establish the connection. Clean + # up after events and such, but DON'T call the command callback (if + # available) because we're going to throw an exception from here # instead. Finish $token "" 1 cleanup $token @@ -367,16 +472,16 @@ proc http::geturl { url args } { } set state(sock) $s - # Wait for the connection to complete + # Wait for the connection to complete. if {$state(-timeout) > 0} { fileevent $s writable [list http::Connect $token] http::wait $token if {$state(status) eq "error"} { - # something went wrong while trying to establish the connection + # Something went wrong while trying to establish the connection. # Clean up after events and such, but DON'T call the command - # callback (if available) because we're going to throw an + # callback (if available) because we're going to throw an # exception from here instead. set err [lindex $state(error) 0] cleanup $token @@ -392,8 +497,8 @@ proc http::geturl { url args } { fconfigure $s -translation {auto crlf} -buffersize $state(-blocksize) - # The following is disallowed in safe interpreters, but the socket - # is already in non-blocking mode in that case. + # The following is disallowed in safe interpreters, but the socket is + # already in non-blocking mode in that case. catch {fconfigure $s -blocking off} set how GET @@ -403,7 +508,7 @@ proc http::geturl { url args } { set how POST set contDone 0 } else { - # there's no query data + # There's no query data. unset state(-query) set isQuery 0 } @@ -421,8 +526,8 @@ proc http::geturl { url args } { puts $s "$how $srvurl HTTP/1.0" puts $s "Accept: $http(-accept)" if {$port == $defport} { - # Don't add port in this case, to handle broken servers. - # [Bug #504508] + # Don't add port in this case, to handle broken servers. [Bug + # 504508] puts $s "Host: $host" } else { puts $s "Host: $host:$port" @@ -440,8 +545,8 @@ proc http::geturl { url args } { } } if {$isQueryChannel && $state(querylength) == 0} { - # Try to determine size of data in channel - # If we cannot seek, the surrounding catch will trap us + # Try to determine size of data in channel. If we cannot seek, the + # surrounding catch will trap us set start [tell $state(-querychannel)] seek $state(-querychannel) 0 end @@ -450,22 +555,21 @@ proc http::geturl { url args } { seek $state(-querychannel) $start } - # Flush the request header and set up the fileevent that will - # either push the POST data or read the response. + # Flush the request header and set up the fileevent that will either + # push the POST data or read the response. # # fileevent note: # - # It is possible to have both the read and write fileevents active - # at this point. The only scenario it seems to affect is a server - # that closes the connection without reading the POST data. - # (e.g., early versions TclHttpd in various error cases). - # Depending on the platform, the client may or may not be able to - # get the response from the server because of the error it will - # get trying to write the post data. Having both fileevents active - # changes the timing and the behavior, but no two platforms - # (among Solaris, Linux, and NT) behave the same, and none - # behave all that well in any case. Servers should always read thier - # POST data if they expect the client to read their response. + # It is possible to have both the read and write fileevents active at + # this point. The only scenario it seems to affect is a server that + # closes the connection without reading the POST data. (e.g., early + # versions TclHttpd in various error cases). Depending on the platform, + # the client may or may not be able to get the response from the server + # because of the error it will get trying to write the post data. + # Having both fileevents active changes the timing and the behavior, + # but no two platforms (among Solaris, Linux, and NT) behave the same, + # and none behave all that well in any case. Servers should always read + # their POST data if they expect the client to read their response. if {$isQuery || $isQueryChannel} { puts $s "Content-Type: $state(-type)" @@ -482,9 +586,8 @@ proc http::geturl { url args } { } if {! [info exists state(-command)]} { - - # geturl does EVERYTHING asynchronously, so if the user - # calls it synchronously, we just do a wait here. + # geturl does EVERYTHING asynchronously, so if the user calls it + # synchronously, we just do a wait here. wait $token if {$state(status) eq "error"} { @@ -494,8 +597,8 @@ proc http::geturl { url args } { } } } err]} { - # The socket probably was never connected, - # or the connection dropped later. + # The socket probably was never connected, or the connection dropped + # later. # Clean up after events and such, but DON'T call the command callback # (if available) because we're going to throw an exception from here @@ -622,8 +725,8 @@ proc http::Write {token} { # Catch I/O errors on dead sockets if {[info exists state(-query)]} { - # Chop up large query strings so queryprogress callback - # can give smooth feedback + # Chop up large query strings so queryprogress callback can give + # smooth feedback. puts -nonewline $s \ [string range $state(-query) $state(queryoffset) \ @@ -644,8 +747,8 @@ proc http::Write {token} { } } } err]} { - # Do not call Finish here, but instead let the read half of - # the socket process whatever server reply there is to get. + # Do not call Finish here, but instead let the read half of the socket + # process whatever server reply there is to get. set state(posterror) $err set done 1 @@ -656,7 +759,7 @@ proc http::Write {token} { fileevent $s readable [list http::Event $token] } - # Callback to the client after we've completely handled everything + # Callback to the client after we've completely handled everything. if {[string length $state(-queryprogress)]} { eval $state(-queryprogress) [list $token $state(querylength)\ @@ -698,10 +801,10 @@ proc http::Event {token} { fconfigure $state(-channel) -translation binary } } else { - # If we are getting text, set the incoming channel's - # encoding correctly. iso8859-1 is the RFC default, but - # this could be any IANA charset. However, we only know - # how to convert what we have encodings for. + # If we are getting text, set the incoming channel's encoding + # correctly. iso8859-1 is the RFC default, but this could be + # any IANA charset. However, we only know how to convert what + # we have encodings for. set idx [lsearch -exact $encodings \ [string tolower $state(charset)]] if {$idx >= 0} { @@ -855,16 +958,15 @@ proc http::wait {token} { # http::formatQuery -- # -# See documentaion for details. -# Call http::formatQuery with an even number of arguments, where -# the first is a name, the second is a value, the third is another -# name, and so on. +# See documentaion for details. Call http::formatQuery with an even +# number of arguments, where the first is a name, the second is a value, +# the third is another name, and so on. # # Arguments: # args A list of name-value pairs. # # Results: -# TODO +# TODO proc http::formatQuery {args} { set result "" @@ -894,9 +996,9 @@ proc http::mapReply {string} { variable http variable formMap - # The spec says: "non-alphanumeric characters are replaced by '%HH'" - # Use a pre-computed map and [string map] to do the conversion - # (much faster than [regsub]/[subst]). [Bug 1020491] + # The spec says: "non-alphanumeric characters are replaced by '%HH'". Use + # a pre-computed map and [string map] to do the conversion (much faster + # than [regsub]/[subst]). [Bug 1020491] if {$http(-urlencoding) ne ""} { set string [encoding convertto $http(-urlencoding) $string] @@ -913,7 +1015,7 @@ proc http::mapReply {string} { } # http::ProxyRequired -- -# Default proxy filter. +# Default proxy filter. # # Arguments: # host The destination host |