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tor-android/external/privoxy/parsers.c

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adding in privoxy directly to Orbot repo
2012-05-03 18:32:18 +00:00
const char parsers_rcs[] = "$Id: parsers.c,v 1.154 2009/03/13 14:10:07 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/parsers.c,v $
*
* Purpose : Declares functions to parse/crunch headers and pages.
* Functions declared include:
* `add_to_iob', `client_cookie_adder', `client_from',
* `client_referrer', `client_send_cookie', `client_ua',
* `client_uagent', `client_x_forwarded',
* `client_x_forwarded_adder', `client_xtra_adder',
* `content_type', `crumble', `destroy_list', `enlist',
* `flush_socket', ``get_header', `sed', `filter_header'
* `server_content_encoding', `server_content_disposition',
* `server_last_modified', `client_accept_language',
* `crunch_client_header', `client_if_modified_since',
* `client_if_none_match', `get_destination_from_headers',
* `parse_header_time', `decompress_iob' and `server_set_cookie'.
*
* Copyright : Written by and Copyright (C) 2001-2009 the
* Privoxy team. http://www.privoxy.org/
*
* Based on the Internet Junkbuster originally written
* by and Copyright (C) 1997 Anonymous Coders and
* Junkbusters Corporation. http://www.junkbusters.com
*
* This program is free software; you can redistribute it
* and/or modify it under the terms of the GNU General
* Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at
* your option) any later version.
*
* This program is distributed in the hope that it will
* be useful, but WITHOUT ANY WARRANTY; without even the
* implied warranty of MERCHANTABILITY or FITNESS FOR A
* PARTICULAR PURPOSE. See the GNU General Public
* License for more details.
*
* The GNU General Public License should be included with
* this file. If not, you can view it at
* http://www.gnu.org/copyleft/gpl.html
* or write to the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Revisions :
* $Log: parsers.c,v $
* Revision 1.154 2009/03/13 14:10:07 fabiankeil
* Fix some more harmless warnings on amd64.
*
* Revision 1.153 2009/03/07 13:09:17 fabiankeil
* Change csp->expected_content and_csp->expected_content_length from
* size_t to unsigned long long to reduce the likelihood of integer
* overflows that would let us close the connection prematurely.
* Bug found while investigating #2669131, reported by cyberpatrol.
*
* Revision 1.152 2009/03/01 18:43:48 fabiankeil
* Help clang understand that we aren't dereferencing
* NULL pointers here.
*
* Revision 1.151 2009/02/15 14:46:35 fabiankeil
* Don't let hide-referrer{conditional-*}} pass
* Referer headers without http URLs.
*
* Revision 1.150 2008/12/04 18:12:19 fabiankeil
* Fix some cparser warnings.
*
* Revision 1.149 2008/11/21 18:39:53 fabiankeil
* In case of CONNECT requests there's no point
* in trying to keep the connection alive.
*
* Revision 1.148 2008/11/16 12:43:49 fabiankeil
* Turn keep-alive support into a runtime feature
* that is disabled by setting keep-alive-timeout
* to a negative value.
*
* Revision 1.147 2008/11/04 17:20:31 fabiankeil
* HTTP/1.1 responses without Connection
* header imply keep-alive. Act accordingly.
*
* Revision 1.146 2008/10/12 16:46:35 fabiankeil
* Remove obsolete warning about delayed delivery with chunked
* transfer encoding and FEATURE_CONNECTION_KEEP_ALIVE enabled.
*
* Revision 1.145 2008/10/09 18:21:41 fabiankeil
* Flush work-in-progress changes to keep outgoing connections
* alive where possible. Incomplete and mostly #ifdef'd out.
*
* Revision 1.144 2008/09/21 13:59:33 fabiankeil
* Treat unknown change-x-forwarded-for parameters as fatal errors.
*
* Revision 1.143 2008/09/21 13:36:52 fabiankeil
* If change-x-forwarded-for{add} is used and the client
* sends multiple X-Forwarded-For headers, append the client's
* IP address to each one of them. "Traditionally" we would
* lose all but the last one.
*
* Revision 1.142 2008/09/20 10:04:33 fabiankeil
* Remove hide-forwarded-for-headers action which has
* been obsoleted by change-x-forwarded-for{block}.
*
* Revision 1.141 2008/09/19 15:26:28 fabiankeil
* Add change-x-forwarded-for{} action to block or add
* X-Forwarded-For headers. Mostly based on code removed
* before 3.0.7.
*
* Revision 1.140 2008/09/12 17:51:43 fabiankeil
* - A few style fixes.
* - Remove a pointless cast.
*
* Revision 1.139 2008/09/04 08:13:58 fabiankeil
* Prepare for critical sections on Windows by adding a
* layer of indirection before the pthread mutex functions.
*
* Revision 1.138 2008/08/30 12:03:07 fabiankeil
* Remove FEATURE_COOKIE_JAR.
*
* Revision 1.137 2008/05/30 15:50:08 fabiankeil
* Remove questionable micro-optimizations
* whose usefulness has never been measured.
*
* Revision 1.136 2008/05/26 16:02:24 fabiankeil
* s@Insufficent@Insufficient@
*
* Revision 1.135 2008/05/21 20:12:10 fabiankeil
* The whole point of strclean() is to modify the
* first parameter, so don't mark it immutable,
* even though the compiler lets us get away with it.
*
* Revision 1.134 2008/05/21 19:27:25 fabiankeil
* As the wafer actions are gone, we can stop including encode.h.
*
* Revision 1.133 2008/05/21 15:50:47 fabiankeil
* Ditch cast from (char **) to (char **).
*
* Revision 1.132 2008/05/21 15:47:14 fabiankeil
* Streamline sed()'s prototype and declare
* the header parse and add structures static.
*
* Revision 1.131 2008/05/20 20:13:30 fabiankeil
* Factor update_server_headers() out of sed(), ditch the
* first_run hack and make server_patterns_light static.
*
* Revision 1.130 2008/05/19 17:18:04 fabiankeil
* Wrap memmove() calls in string_move()
* to document the purpose in one place.
*
* Revision 1.129 2008/05/17 14:02:07 fabiankeil
* Normalize linear header white space.
*
* Revision 1.128 2008/05/16 16:39:03 fabiankeil
* If a header is split across multiple lines,
* merge them to a single line before parsing them.
*
* Revision 1.127 2008/05/10 13:23:38 fabiankeil
* Don't provide get_header() with the whole client state
* structure when it only needs access to csp->iob.
*
* Revision 1.126 2008/05/03 16:40:45 fabiankeil
* Change content_filters_enabled()'s parameter from
* csp->action to action so it can be also used in the
* CGI code. Don't bother checking if there are filters
* loaded, as that's somewhat besides the point.
*
* Revision 1.125 2008/04/17 14:40:49 fabiankeil
* Provide get_http_time() with the buffer size so it doesn't
* have to blindly assume that the buffer is big enough.
*
* Revision 1.124 2008/04/16 16:38:21 fabiankeil
* Don't pass the whole csp structure to flush_socket()
* when it only needs a file descriptor and a buffer.
*
* Revision 1.123 2008/03/29 12:13:46 fabiankeil
* Remove send-wafer and send-vanilla-wafer actions.
*
* Revision 1.122 2008/03/28 15:13:39 fabiankeil
* Remove inspect-jpegs action.
*
* Revision 1.121 2008/01/05 21:37:03 fabiankeil
* Let client_range() also handle Request-Range headers
* which apparently are still supported by many servers.
*
* Revision 1.120 2008/01/04 17:43:45 fabiankeil
* Improve the warning messages that get logged if the action files
* "enable" filters but no filters of that type have been loaded.
*
* Revision 1.119 2007/12/28 18:32:51 fabiankeil
* In server_content_type():
* - Don't require leading white space when detecting image content types.
* - Change '... not replaced ...' message to sound less crazy if the text
* type actually is 'text/plain'.
* - Mark the 'text/plain == binary data' assumption for removal.
* - Remove a bunch of trailing white space.
*
* Revision 1.118 2007/12/28 16:56:35 fabiankeil
* Minor server_content_disposition() changes:
* - Don't regenerate the header name all lower-case.
* - Some white space fixes.
* - Remove useless log message in case of ENOMEM.
*
* Revision 1.117 2007/12/06 18:11:50 fabiankeil
* Garbage-collect the code to add a X-Forwarded-For
* header as it seems to be mostly used by accident.
*
* Revision 1.116 2007/12/01 13:04:22 fabiankeil
* Fix a crash on mingw32 with some Last Modified times in the future.
*
* Revision 1.115 2007/11/02 16:52:50 fabiankeil
* Remove a "can't happen" error block which, over
* time, mutated into a "guaranteed to happen" block.
*
* Revision 1.114 2007/10/19 16:56:26 fabiankeil
* - Downgrade "Buffer limit reached" message to LOG_LEVEL_INFO.
* - Use shiny new content_filters_enabled() in client_range().
*
* Revision 1.113 2007/10/10 17:29:57 fabiankeil
* I forgot about Poland.
*
* Revision 1.112 2007/10/09 16:38:40 fabiankeil
* Remove Range and If-Range headers if content filtering is enabled.
*
* Revision 1.111 2007/10/04 18:07:00 fabiankeil
* Move ACTION_VANILLA_WAFER handling from jcc's chat() into
* client_cookie_adder() to make sure send-vanilla-wafer can be
* controlled through tags (and thus regression-tested).
*
* Revision 1.110 2007/09/29 10:42:37 fabiankeil
* - Remove "scanning headers for" log message again.
* - Some more whitespace fixes.
*
* Revision 1.109 2007/09/08 14:25:48 fabiankeil
* Refactor client_referrer() and add conditional-forge parameter.
*
* Revision 1.108 2007/08/28 18:21:03 fabiankeil
* A bunch of whitespace fixes, pointy hat to me.
*
* Revision 1.107 2007/08/28 18:16:32 fabiankeil
* Fix possible memory corruption in server_http, make sure it's not
* executed for ordinary server headers and mark some problems for later.
*
* Revision 1.106 2007/08/18 14:30:32 fabiankeil
* Let content-type-overwrite{} honour force-text-mode again.
*
* Revision 1.105 2007/08/11 14:49:49 fabiankeil
* - Add prototpyes for the header parsers and make them static.
* - Comment out client_accept_encoding_adder() which isn't used right now.
*
* Revision 1.104 2007/07/14 07:38:19 fabiankeil
* Move the ACTION_FORCE_TEXT_MODE check out of
* server_content_type(). Signal other functions
* whether or not a content type has been declared.
* Part of the fix for BR#1750917.
*
* Revision 1.103 2007/06/01 16:31:54 fabiankeil
* Change sed() to return a jb_err in preparation for forward-override{}.
*
* Revision 1.102 2007/05/27 12:39:32 fabiankeil
* Adjust "X-Filter: No" to disable dedicated header filters.
*
* Revision 1.101 2007/05/14 10:16:41 fabiankeil
* Streamline client_cookie_adder().
*
* Revision 1.100 2007/04/30 15:53:11 fabiankeil
* Make sure filters with dynamic jobs actually use them.
*
* Revision 1.99 2007/04/30 15:06:26 fabiankeil
* - Introduce dynamic pcrs jobs that can resolve variables.
* - Remove unnecessary update_action_bits_for_all_tags() call.
*
* Revision 1.98 2007/04/17 18:32:10 fabiankeil
* - Make tagging based on tags set by earlier taggers
* of the same kind possible.
* - Log whether or not new tags cause action bits updates
* (in which case a matching tag-pattern section exists).
* - Log if the user tries to set a tag that is already set.
*
* Revision 1.97 2007/04/15 16:39:21 fabiankeil
* Introduce tags as alternative way to specify which
* actions apply to a request. At the moment tags can be
* created based on client and server headers.
*
* Revision 1.96 2007/04/12 12:53:58 fabiankeil
* Log a warning if the content is compressed, filtering is
* enabled and Privoxy was compiled without zlib support.
* Closes FR#1673938.
*
* Revision 1.95 2007/03/25 14:26:40 fabiankeil
* - Fix warnings when compiled with glibc.
* - Don't use crumble() for cookie crunching.
* - Move cookie time parsing into parse_header_time().
* - Let parse_header_time() return a jb_err code
* instead of a pointer that can only be used to
* check for NULL anyway.
*
* Revision 1.94 2007/03/21 12:23:53 fabiankeil
* - Add better protection against malicious gzip headers.
* - Stop logging the first hundred bytes of decompressed content.
* It looks like it's working and there is always debug 16.
* - Log the content size after decompression in decompress_iob()
* instead of pcrs_filter_response().
*
* Revision 1.93 2007/03/20 15:21:44 fabiankeil
* - Use dedicated header filter actions instead of abusing "filter".
* Replace "filter-client-headers" and "filter-client-headers"
* with "server-header-filter" and "client-header-filter".
* - Remove filter_client_header() and filter_client_header(),
* filter_header() now checks the shiny new
* CSP_FLAG_CLIENT_HEADER_PARSING_DONE flag instead.
*
* Revision 1.92 2007/03/05 13:25:32 fabiankeil
* - Cosmetical changes for LOG_LEVEL_RE_FILTER messages.
* - Handle "Cookie:" and "Connection:" headers a bit smarter
* (don't crunch them just to recreate them later on).
* - Add another non-standard time format for the cookie
* expiration date detection.
* - Fix a valgrind warning.
*
* Revision 1.91 2007/02/24 12:27:32 fabiankeil
* Improve cookie expiration date detection.
*
* Revision 1.90 2007/02/08 19:12:35 fabiankeil
* Don't run server_content_length() the first time
* sed() parses server headers; only adjust the
* Content-Length header if the page was modified.
*
* Revision 1.89 2007/02/07 16:52:11 fabiankeil
* Fix log messages regarding the cookie time format
* (cookie and request URL were mixed up).
*
* Revision 1.88 2007/02/07 11:27:12 fabiankeil
* - Let decompress_iob()
* - not corrupt the content if decompression fails
* early. (the first byte(s) were lost).
* - use pointer arithmetics with defined outcome for
* a change.
* - Use a different kludge to remember a failed decompression.
*
* Revision 1.87 2007/01/31 16:21:38 fabiankeil
* Search for Max-Forwards headers case-insensitive,
* don't generate the "501 unsupported" message for invalid
* Max-Forwards values and don't increase negative ones.
*
* Revision 1.86 2007/01/30 13:05:26 fabiankeil
* - Let server_set_cookie() check the expiration date
* of cookies and don't touch the ones that are already
* expired. Fixes problems with low quality web applications
* as described in BR 932612.
*
* - Adjust comment in client_max_forwards to reality;
* remove invalid Max-Forwards headers.
*
* Revision 1.85 2007/01/26 15:33:46 fabiankeil
* Stop filter_header() from unintentionally removing
* empty header lines that were enlisted by the continue
* hack.
*
* Revision 1.84 2007/01/24 12:56:52 fabiankeil
* - Repeat the request URL before logging any headers.
* Makes reading the log easier in case of simultaneous requests.
* - If there are more than one Content-Type headers in one request,
* use the first one and remove the others.
* - Remove "newval" variable in server_content_type().
* It's only used once.
*
* Revision 1.83 2007/01/12 15:03:02 fabiankeil
* Correct a cast, check inflateEnd() exit code
* to see if we have to, replace sprintf calls
* with snprintf.
*
* Revision 1.82 2007/01/01 19:36:37 fabiankeil
* Integrate a modified version of Wil Mahan's
* zlib patch (PR #895531).
*
* Revision 1.81 2006/12/31 22:21:33 fabiankeil
* Skip empty filter files in filter_header()
* but don't ignore the ones that come afterwards.
* Fixes BR 1619208, this time for real.
*
* Revision 1.80 2006/12/29 19:08:22 fabiankeil
* Reverted parts of my last commit
* to keep error handling working.
*
* Revision 1.79 2006/12/29 18:04:40 fabiankeil
* Fixed gcc43 conversion warnings.
*
* Revision 1.78 2006/12/26 17:19:20 fabiankeil
* Bringing back the "useless" localtime() call
* I removed in revision 1.67. On some platforms
* it's necessary to prevent time zone offsets.
*
* Revision 1.77 2006/12/07 18:44:26 fabiankeil
* Rebuild request URL in get_destination_from_headers()
* to make sure redirect{pcrs command} works as expected
* for intercepted requests.
*
* Revision 1.76 2006/12/06 19:52:25 fabiankeil
* Added get_destination_from_headers().
*
* Revision 1.75 2006/11/13 19:05:51 fabiankeil
* Make pthread mutex locking more generic. Instead of
* checking for OSX and OpenBSD, check for FEATURE_PTHREAD
* and use mutex locking unless there is an _r function
* available. Better safe than sorry.
*
* Fixes "./configure --disable-pthread" and should result
* in less threading-related problems on pthread-using platforms,
* but it still doesn't fix BR#1122404.
*
* Revision 1.74 2006/10/02 16:59:12 fabiankeil
* The special header "X-Filter: No" now disables
* header filtering as well.
*
* Revision 1.73 2006/09/23 13:26:38 roro
* Replace TABs by spaces in source code.
*
* Revision 1.72 2006/09/23 12:37:21 fabiankeil
* Don't print a log message every time filter_headers is
* entered or left. It only creates noise without any real
* information.
*
* Revision 1.71 2006/09/21 19:55:17 fabiankeil
* Fix +hide-if-modified-since{-n}.
*
* Revision 1.70 2006/09/08 12:06:34 fabiankeil
* Have hide-if-modified-since interpret the random
* range value as minutes instead of hours. Allows
* more fine-grained configuration.
*
* Revision 1.69 2006/09/06 16:25:51 fabiankeil
* Always have parse_header_time return a pointer
* that actual makes sense, even though we currently
* only need it to detect problems.
*
* Revision 1.68 2006/09/06 10:43:32 fabiankeil
* Added config option enable-remote-http-toggle
* to specify if Privoxy should recognize special
* headers (currently only X-Filter) to change its
* behaviour. Disabled by default.
*
* Revision 1.67 2006/09/04 11:01:26 fabiankeil
* After filtering de-chunked instances, remove
* "Transfer-Encoding" header entirely instead of changing
* it to "Transfer-Encoding: identity", which is invalid.
* Thanks Michael Shields <shields@msrl.com>. Fixes PR 1318658.
*
* Don't use localtime in parse_header_time. An empty time struct
* is good enough, it gets overwritten by strptime anyway.
*
* Revision 1.66 2006/09/03 19:38:28 fabiankeil
* Use gmtime_r if available, fallback to gmtime with mutex
* protection for MacOSX and use vanilla gmtime for the rest.
*
* Revision 1.65 2006/08/22 10:55:56 fabiankeil
* Changed client_referrer to use the right type (size_t) for
* hostlenght and to shorten the temporary referrer string with
* '\0' instead of adding a useless line break.
*
* Revision 1.64 2006/08/17 17:15:10 fabiankeil
* - Back to timegm() using GnuPG's replacement if necessary.
* Using mktime() and localtime() could add a on hour offset if
* the randomize factor was big enough to lead to a summer/wintertime
* switch.
*
* - Removed now-useless Privoxy 3.0.3 compatibility glue.
*
* - Moved randomization code into pick_from_range().
*
* - Changed parse_header_time definition.
* time_t isn't guaranteed to be signed and
* if it isn't, -1 isn't available as error code.
* Changed some variable types in client_if_modified_since()
* because of the same reason.
*
* Revision 1.63 2006/08/14 13:18:08 david__schmidt
* OS/2 compilation compatibility fixups
*
* Revision 1.62 2006/08/14 08:58:42 fabiankeil
* Changed include from strptime.c to strptime.h
*
* Revision 1.61 2006/08/14 08:25:19 fabiankeil
* Split filter-headers{} into filter-client-headers{}
* and filter-server-headers{}.
* Added parse_header_time() to share some code.
* Replaced timegm() with mktime().
*
* Revision 1.60 2006/08/12 03:54:37 david__schmidt
* Windows service integration
*
* Revision 1.59 2006/08/03 02:46:41 david__schmidt
* Incorporate Fabian Keil's patch work: http://www.fabiankeil.de/sourcecode/privoxy/
*
* Revision 1.58 2006/07/18 14:48:47 david__schmidt
* Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
* with what was really the latest development (the v_3_0_branch branch)
*
* Revision 1.56.2.10 2006/01/21 16:16:08 david__schmidt
* Thanks to Edward Carrel for his patch to modernize OSX's pthreads support. See bug #1409623.
*
* Revision 1.56.2.9 2004/10/03 12:53:45 david__schmidt
* Add the ability to check jpeg images for invalid
* lengths of comment blocks. Defensive strategy
* against the exploit:
* Microsoft Security Bulletin MS04-028
* Buffer Overrun in JPEG Processing (GDI+) Could
* Allow Code Execution (833987)
* Enabled with +inspect-jpegs in actions files.
*
* Revision 1.56.2.8 2003/07/11 13:21:25 oes
* Excluded text/plain objects from filtering. This fixes a
* couple of client-crashing, download corruption and
* Privoxy performance issues, whose root cause lies in
* web servers labelling content of unknown type as text/plain.
*
* Revision 1.56.2.7 2003/05/06 12:07:26 oes
* Fixed bug #729900: Suspicious HOST: headers are now killed and regenerated if necessary
*
* Revision 1.56.2.6 2003/04/14 21:28:30 oes
* Completing the previous change
*
* Revision 1.56.2.5 2003/04/14 12:08:16 oes
* Added temporary workaround for bug in PHP < 4.2.3
*
* Revision 1.56.2.4 2003/03/07 03:41:05 david__schmidt
* Wrapping all *_r functions (the non-_r versions of them) with mutex semaphores for OSX. Hopefully this will take care of all of those pesky crash reports.
*
* Revision 1.56.2.3 2002/11/10 04:20:02 hal9
* Fix typo: supressed -> suppressed
*
* Revision 1.56.2.2 2002/09/25 14:59:53 oes
* Improved cookie logging
*
* Revision 1.56.2.1 2002/09/25 14:52:45 oes
* Added basic support for OPTIONS and TRACE HTTP methods:
* - New parser function client_max_forwards which decrements
* the Max-Forwards HTTP header field of OPTIONS and TRACE
* requests by one before forwarding
* - New parser function client_host which extracts the host
* and port information from the HTTP header field if the
* request URI was not absolute
* - Don't crumble and re-add the Host: header, but only generate
* and append if missing
*
* Revision 1.56 2002/05/12 15:34:22 jongfoster
* Fixing typo in a comment
*
* Revision 1.55 2002/05/08 16:01:07 oes
* Optimized add_to_iob:
* - Use realloc instead of malloc(), memcpy(), free()
* - Expand to powers of two if possible, to get
* O(log n) reallocs instead of O(n).
* - Moved check for buffer limit here from chat
* - Report failure via returncode
*
* Revision 1.54 2002/04/02 15:03:16 oes
* Tiny code cosmetics
*
* Revision 1.53 2002/03/26 22:29:55 swa
* we have a new homepage!
*
* Revision 1.52 2002/03/24 13:25:43 swa
* name change related issues
*
* Revision 1.51 2002/03/13 00:27:05 jongfoster
* Killing warnings
*
* Revision 1.50 2002/03/12 01:45:35 oes
* More verbose logging
*
* Revision 1.49 2002/03/09 20:03:52 jongfoster
* - Making various functions return int rather than size_t.
* (Undoing a recent change). Since size_t is unsigned on
* Windows, functions like read_socket that return -1 on
* error cannot return a size_t.
*
* THIS WAS A MAJOR BUG - it caused frequent, unpredictable
* crashes, and also frequently caused JB to jump to 100%
* CPU and stay there. (Because it thought it had just
* read ((unsigned)-1) == 4Gb of data...)
*
* - The signature of write_socket has changed, it now simply
* returns success=0/failure=nonzero.
*
* - Trying to get rid of a few warnings --with-debug on
* Windows, I've introduced a new type "jb_socket". This is
* used for the socket file descriptors. On Windows, this
* is SOCKET (a typedef for unsigned). Everywhere else, it's
* an int. The error value can't be -1 any more, so it's
* now JB_INVALID_SOCKET (which is -1 on UNIX, and in
* Windows it maps to the #define INVALID_SOCKET.)
*
* - The signature of bind_port has changed.
*
* Revision 1.48 2002/03/07 03:46:53 oes
* Fixed compiler warnings etc
*
* Revision 1.47 2002/02/20 23:15:13 jongfoster
* Parsing functions now handle out-of-memory gracefully by returning
* an error code.
*
* Revision 1.46 2002/01/17 21:03:47 jongfoster
* Moving all our URL and URL pattern parsing code to urlmatch.c.
*
* Revision 1.45 2002/01/09 14:33:03 oes
* Added support for localtime_r.
*
* Revision 1.44 2001/12/14 01:22:54 steudten
* Remove 'user:pass@' from 'proto://user:pass@host' for the
* new added header 'Host: ..'. (See Req ID 491818)
*
* Revision 1.43 2001/11/23 00:26:38 jongfoster
* Fixing two really stupid errors in my previous commit
*
* Revision 1.42 2001/11/22 21:59:30 jongfoster
* Adding code to handle +no-cookies-keep
*
* Revision 1.41 2001/11/05 23:43:05 steudten
* Add time+date to log files.
*
* Revision 1.40 2001/10/26 20:13:09 jongfoster
* ctype.h is needed in Windows, too.
*
* Revision 1.39 2001/10/26 17:40:04 oes
* Introduced get_header_value()
* Removed http->user_agent, csp->referrer and csp->accept_types
* Removed client_accept()
*
* Revision 1.38 2001/10/25 03:40:48 david__schmidt
* Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple
* threads to call select() simultaneously. So, it's time to do a real, live,
* native OS/2 port. See defines for __EMX__ (the porting layer) vs. __OS2__
* (native). Both versions will work, but using __OS2__ offers multi-threading.
*
* Revision 1.37 2001/10/23 21:36:02 jongfoster
* Documenting sed()'s error behaviou (doc change only)
*
* Revision 1.36 2001/10/13 12:51:51 joergs
* Removed client_host, (was only required for the old 2.0.2-11 http://noijb.
* force-load), instead crumble Host: and add it (again) in client_host_adder
* (in case we get a HTTP/1.0 request without Host: header and forward it to
* a HTTP/1.1 server/proxy).
*
* Revision 1.35 2001/10/09 22:39:21 jongfoster
* assert.h is also required under Win32, so moving out of #ifndef _WIN32
* block.
*
* Revision 1.34 2001/10/07 18:50:55 oes
* Added server_content_encoding, renamed server_transfer_encoding
*
* Revision 1.33 2001/10/07 18:04:49 oes
* Changed server_http11 to server_http and its pattern to "HTTP".
* Additional functionality: it now saves the HTTP status into
* csp->http->status and sets CT_TABOO for Status 206 (partial range)
*
* Revision 1.32 2001/10/07 15:43:28 oes
* Removed FEATURE_DENY_GZIP and replaced it with client_accept_encoding,
* client_te and client_accept_encoding_adder, triggered by the new
* +no-compression action. For HTTP/1.1 the Accept-Encoding header is
* changed to allow only identity and chunked, and the TE header is
* crunched. For HTTP/1.0, Accept-Encoding is crunched.
*
* parse_http_request no longer does anything than parsing. The rewriting
* of http->cmd and version mangling are gone. It now also recognizes
* the put and delete methods and saves the url in http->url. Removed
* unused variable.
*
* renamed content_type and content_length to have the server_ prefix
*
* server_content_type now only works if csp->content_type != CT_TABOO
*
* added server_transfer_encoding, which
* - Sets CT_TABOO to prohibit filtering if encoding compresses
* - Raises the CSP_FLAG_CHUNKED flag if Encoding is "chunked"
* - Change from "chunked" to "identity" if body was chunked
* but has been de-chunked for filtering.
*
* added server_content_md5 which crunches any Content-MD5 headers
* if the body was modified.
*
* made server_http11 conditional on +downgrade action
*
* Replaced 6 boolean members of csp with one bitmap (csp->flags)
*
* Revision 1.31 2001/10/05 14:25:02 oes
* Crumble Keep-Alive from Server
*
* Revision 1.30 2001/09/29 12:56:03 joergs
* IJB now changes HTTP/1.1 to HTTP/1.0 in requests and answers.
*
* Revision 1.29 2001/09/24 21:09:24 jongfoster
* Fixing 2 memory leaks that Guy spotted, where the paramater to
* enlist() was not being free()d.
*
* Revision 1.28 2001/09/22 16:32:28 jongfoster
* Removing unused #includes.
*
* Revision 1.27 2001/09/20 15:45:25 steudten
*
* add casting from size_t to int for printf()
* remove local variable shadow s2
*
* Revision 1.26 2001/09/16 17:05:14 jongfoster
* Removing unused #include showarg.h
*
* Revision 1.25 2001/09/16 13:21:27 jongfoster
* Changes to use new list functions.
*
* Revision 1.24 2001/09/13 23:05:50 jongfoster
* Changing the string paramater to the header parsers a "const".
*
* Revision 1.23 2001/09/12 18:08:19 steudten
*
* In parse_http_request() header rewriting miss the host value, so
* from http://www.mydomain.com the result was just " / " not
* http://www.mydomain.com/ in case we forward.
*
* Revision 1.22 2001/09/10 10:58:53 oes
* Silenced compiler warnings
*
* Revision 1.21 2001/07/31 14:46:00 oes
* - Persistant connections now suppressed
* - sed() no longer appends empty header to csp->headers
*
* Revision 1.20 2001/07/30 22:08:36 jongfoster
* Tidying up #defines:
* - All feature #defines are now of the form FEATURE_xxx
* - Permanently turned off WIN_GUI_EDIT
* - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS
*
* Revision 1.19 2001/07/25 17:21:54 oes
* client_uagent now saves copy of User-Agent: header value
*
* Revision 1.18 2001/07/13 14:02:46 oes
* - Included fix to repair broken HTTP requests that
* don't contain a path, not even '/'.
* - Removed all #ifdef PCRS
* - content_type now always inspected and classified as
* text, gif or other.
* - formatting / comments
*
* Revision 1.17 2001/06/29 21:45:41 oes
* Indentation, CRLF->LF, Tab-> Space
*
* Revision 1.16 2001/06/29 13:32:42 oes
* - Fixed a comment
* - Adapted free_http_request
* - Removed logentry from cancelled commit
*
* Revision 1.15 2001/06/03 19:12:38 oes
* deleted const struct interceptors
*
* Revision 1.14 2001/06/01 18:49:17 jongfoster
* Replaced "list_share" with "list" - the tiny memory gain was not
* worth the extra complexity.
*
* Revision 1.13 2001/05/31 21:30:33 jongfoster
* Removed list code - it's now in list.[ch]
* Renamed "permission" to "action", and changed many features
* to use the actions file rather than the global config.
*
* Revision 1.12 2001/05/31 17:33:13 oes
*
* CRLF -> LF
*
* Revision 1.11 2001/05/29 20:11:19 joergs
* '/ * inside comment' warning removed.
*
* Revision 1.10 2001/05/29 09:50:24 jongfoster
* Unified blocklist/imagelist/permissionslist.
* File format is still under discussion, but the internal changes
* are (mostly) done.
*
* Also modified interceptor behaviour:
* - We now intercept all URLs beginning with one of the following
* prefixes (and *only* these prefixes):
* * http://i.j.b/
* * http://ijbswa.sf.net/config/
* * http://ijbswa.sourceforge.net/config/
* - New interceptors "home page" - go to http://i.j.b/ to see it.
* - Internal changes so that intercepted and fast redirect pages
* are not replaced with an image.
* - Interceptors now have the option to send a binary page direct
* to the client. (i.e. ijb-send-banner uses this)
* - Implemented show-url-info interceptor. (Which is why I needed
* the above interceptors changes - a typical URL is
* "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif".
* The previous mechanism would not have intercepted that, and
* if it had been intercepted then it then it would have replaced
* it with an image.)
*
* Revision 1.9 2001/05/28 17:26:33 jongfoster
* Fixing segfault if last header was crunched.
* Fixing Windows build (snprintf() is _snprintf() under Win32, but we
* can use the cross-platform sprintf() instead.)
*
* Revision 1.8 2001/05/27 22:17:04 oes
*
* - re_process_buffer no longer writes the modified buffer
* to the client, which was very ugly. It now returns the
* buffer, which it is then written by chat.
*
* - content_length now adjusts the Content-Length: header
* for modified documents rather than crunch()ing it.
* (Length info in csp->content_length, which is 0 for
* unmodified documents)
*
* - For this to work, sed() is called twice when filtering.
*
* Revision 1.7 2001/05/27 13:19:06 oes
* Patched Joergs solution for the content-length in.
*
* Revision 1.6 2001/05/26 13:39:32 jongfoster
* Only crunches Content-Length header if applying RE filtering.
* Without this fix, Microsoft Windows Update wouldn't work.
*
* Revision 1.5 2001/05/26 00:28:36 jongfoster
* Automatic reloading of config file.
* Removed obsolete SIGHUP support (Unix) and Reload menu option (Win32).
* Most of the global variables have been moved to a new
* struct configuration_spec, accessed through csp->config->globalname
* Most of the globals remaining are used by the Win32 GUI.
*
* Revision 1.4 2001/05/22 18:46:04 oes
*
* - Enabled filtering banners by size rather than URL
* by adding patterns that replace all standard banner
* sizes with the "Junkbuster" gif to the re_filterfile
*
* - Enabled filtering WebBugs by providing a pattern
* which kills all 1x1 images
*
* - Added support for PCRE_UNGREEDY behaviour to pcrs,
* which is selected by the (nonstandard and therefore
* capital) letter 'U' in the option string.
* It causes the quantifiers to be ungreedy by default.
* Appending a ? turns back to greedy (!).
*
* - Added a new interceptor ijb-send-banner, which
* sends back the "Junkbuster" gif. Without imagelist or
* MSIE detection support, or if tinygif = 1, or the
* URL isn't recognized as an imageurl, a lame HTML
* explanation is sent instead.
*
* - Added new feature, which permits blocking remote
* script redirects and firing back a local redirect
* to the browser.
* The feature is conditionally compiled, i.e. it
* can be disabled with --disable-fast-redirects,
* plus it must be activated by a "fast-redirects"
* line in the config file, has its own log level
* and of course wants to be displayed by show-proxy-args
* Note: Boy, all the #ifdefs in 1001 locations and
* all the fumbling with configure.in and acconfig.h
* were *way* more work than the feature itself :-(
*
* - Because a generic redirect template was needed for
* this, tinygif = 3 now uses the same.
*
* - Moved GIFs, and other static HTTP response templates
* to project.h
*
* - Some minor fixes
*
* - Removed some >400 CRs again (Jon, you really worked
* a lot! ;-)
*
* Revision 1.3 2001/05/20 01:21:20 jongfoster
* Version 2.9.4 checkin.
* - Merged popupfile and cookiefile, and added control over PCRS
* filtering, in new "permissionsfile".
* - Implemented LOG_LEVEL_FATAL, so that if there is a configuration
* file error you now get a message box (in the Win32 GUI) rather
* than the program exiting with no explanation.
* - Made killpopup use the PCRS MIME-type checking and HTTP-header
* skipping.
* - Removed tabs from "config"
* - Moved duplicated url parsing code in "loaders.c" to a new funcition.
* - Bumped up version number.
*
* Revision 1.2 2001/05/17 23:02:36 oes
* - Made referrer option accept 'L' as a substitute for '<EFBFBD>'
*
* Revision 1.1.1.1 2001/05/15 13:59:01 oes
* Initial import of version 2.9.3 source tree
*
*
*********************************************************************/
#include "config.h"
#ifndef _WIN32
#include <stdio.h>
#include <sys/types.h>
#endif
#include <stdlib.h>
#include <ctype.h>
#include <assert.h>
#include <string.h>
#ifdef __GLIBC__
/*
* Convince GNU's libc to provide a strptime prototype.
*/
#define __USE_XOPEN
#endif /*__GLIBC__ */
#include <time.h>
#ifdef FEATURE_ZLIB
#include <zlib.h>
#endif
#if !defined(_WIN32) && !defined(__OS2__)
#include <unistd.h>
#endif
#include "project.h"
#ifdef FEATURE_PTHREAD
#include "jcc.h"
/* jcc.h is for mutex semapores only */
#endif /* def FEATURE_PTHREAD */
#include "list.h"
#include "parsers.h"
#include "ssplit.h"
#include "errlog.h"
#include "jbsockets.h"
#include "miscutil.h"
#include "list.h"
#include "actions.h"
#include "filters.h"
#ifndef HAVE_STRPTIME
#include "strptime.h"
#endif
const char parsers_h_rcs[] = PARSERS_H_VERSION;
/* Fix a problem with Solaris. There should be no effect on other
* platforms.
* Solaris's isspace() is a macro which uses its argument directly
* as an array index. Therefore we need to make sure that high-bit
* characters generate +ve values, and ideally we also want to make
* the argument match the declared parameter type of "int".
*
* Why did they write a character function that can't take a simple
* "char" argument? Doh!
*/
#define ijb_isupper(__X) isupper((int)(unsigned char)(__X))
#define ijb_tolower(__X) tolower((int)(unsigned char)(__X))
static char *get_header_line(struct iob *iob);
static jb_err scan_headers(struct client_state *csp);
static jb_err header_tagger(struct client_state *csp, char *header);
static jb_err parse_header_time(const char *header_time, time_t *result);
static jb_err crumble (struct client_state *csp, char **header);
static jb_err filter_header (struct client_state *csp, char **header);
static jb_err client_connection (struct client_state *csp, char **header);
static jb_err client_referrer (struct client_state *csp, char **header);
static jb_err client_uagent (struct client_state *csp, char **header);
static jb_err client_ua (struct client_state *csp, char **header);
static jb_err client_from (struct client_state *csp, char **header);
static jb_err client_send_cookie (struct client_state *csp, char **header);
static jb_err client_x_forwarded (struct client_state *csp, char **header);
static jb_err client_accept_encoding (struct client_state *csp, char **header);
static jb_err client_te (struct client_state *csp, char **header);
static jb_err client_max_forwards (struct client_state *csp, char **header);
static jb_err client_host (struct client_state *csp, char **header);
static jb_err client_if_modified_since (struct client_state *csp, char **header);
static jb_err client_accept_language (struct client_state *csp, char **header);
static jb_err client_if_none_match (struct client_state *csp, char **header);
static jb_err crunch_client_header (struct client_state *csp, char **header);
static jb_err client_x_filter (struct client_state *csp, char **header);
static jb_err client_range (struct client_state *csp, char **header);
static jb_err server_set_cookie (struct client_state *csp, char **header);
static jb_err server_connection (struct client_state *csp, char **header);
static jb_err server_content_type (struct client_state *csp, char **header);
static jb_err server_adjust_content_length(struct client_state *csp, char **header);
static jb_err server_content_md5 (struct client_state *csp, char **header);
static jb_err server_content_encoding (struct client_state *csp, char **header);
static jb_err server_transfer_coding (struct client_state *csp, char **header);
static jb_err server_http (struct client_state *csp, char **header);
static jb_err crunch_server_header (struct client_state *csp, char **header);
static jb_err server_last_modified (struct client_state *csp, char **header);
static jb_err server_content_disposition(struct client_state *csp, char **header);
#ifdef FEATURE_CONNECTION_KEEP_ALIVE
static jb_err server_save_content_length(struct client_state *csp, char **header);
#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
static jb_err client_host_adder (struct client_state *csp);
static jb_err client_xtra_adder (struct client_state *csp);
static jb_err client_x_forwarded_for_adder(struct client_state *csp);
static jb_err client_connection_header_adder(struct client_state *csp);
static jb_err server_connection_close_adder(struct client_state *csp);
static jb_err create_forged_referrer(char **header, const char *hostport);
static jb_err create_fake_referrer(char **header, const char *fake_referrer);
static jb_err handle_conditional_hide_referrer_parameter(char **header,
const char *host, const int parameter_conditional_block);
static const char *get_appropiate_connection_header(const struct client_state *csp);
/*
* List of functions to run on a list of headers.
*/
struct parsers
{
/** The header prefix to match */
const char *str;
/** The length of the prefix to match */
const size_t len;
/** The function to apply to this line */
const parser_func_ptr parser;
};
static const struct parsers client_patterns[] = {
{ "referer:", 8, client_referrer },
{ "user-agent:", 11, client_uagent },
{ "ua-", 3, client_ua },
{ "from:", 5, client_from },
{ "cookie:", 7, client_send_cookie },
{ "x-forwarded-for:", 16, client_x_forwarded },
{ "Accept-Encoding:", 16, client_accept_encoding },
{ "TE:", 3, client_te },
{ "Host:", 5, client_host },
{ "if-modified-since:", 18, client_if_modified_since },
{ "Keep-Alive:", 11, crumble },
{ "connection:", 11, client_connection },
{ "proxy-connection:", 17, crumble },
{ "max-forwards:", 13, client_max_forwards },
{ "Accept-Language:", 16, client_accept_language },
{ "if-none-match:", 14, client_if_none_match },
{ "Range:", 6, client_range },
{ "Request-Range:", 14, client_range },
{ "If-Range:", 9, client_range },
{ "X-Filter:", 9, client_x_filter },
{ "*", 0, crunch_client_header },
{ "*", 0, filter_header },
{ NULL, 0, NULL }
};
static const struct parsers server_patterns[] = {
{ "HTTP/", 5, server_http },
{ "set-cookie:", 11, server_set_cookie },
{ "connection:", 11, server_connection },
{ "Content-Type:", 13, server_content_type },
{ "Content-MD5:", 12, server_content_md5 },
{ "Content-Encoding:", 17, server_content_encoding },
#ifdef FEATURE_CONNECTION_KEEP_ALIVE
{ "Content-Length:", 15, server_save_content_length },
#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
{ "Transfer-Encoding:", 18, server_transfer_coding },
{ "Keep-Alive:", 11, crumble },
{ "content-disposition:", 20, server_content_disposition },
{ "Last-Modified:", 14, server_last_modified },
{ "*", 0, crunch_server_header },
{ "*", 0, filter_header },
{ NULL, 0, NULL }
};
static const add_header_func_ptr add_client_headers[] = {
client_host_adder,
client_x_forwarded_for_adder,
client_xtra_adder,
/* Temporarily disabled: client_accept_encoding_adder, */
client_connection_header_adder,
NULL
};
static const add_header_func_ptr add_server_headers[] = {
server_connection_close_adder,
NULL
};
/*********************************************************************
*
* Function : flush_socket
*
* Description : Write any pending "buffered" content.
*
* Parameters :
* 1 : fd = file descriptor of the socket to read
* 2 : iob = The I/O buffer to flush, usually csp->iob.
*
* Returns : On success, the number of bytes written are returned (zero
* indicates nothing was written). On error, -1 is returned,
* and errno is set appropriately. If count is zero and the
* file descriptor refers to a regular file, 0 will be
* returned without causing any other effect. For a special
* file, the results are not portable.
*
*********************************************************************/
long flush_socket(jb_socket fd, struct iob *iob)
{
long len = iob->eod - iob->cur;
if (len <= 0)
{
return(0);
}
if (write_socket(fd, iob->cur, (size_t)len))
{
return(-1);
}
iob->eod = iob->cur = iob->buf;
return(len);
}
/*********************************************************************
*
* Function : add_to_iob
*
* Description : Add content to the buffered page, expanding the
* buffer if necessary.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : buf = holds the content to be added to the page
* 3 : n = number of bytes to be added
*
* Returns : JB_ERR_OK on success, JB_ERR_MEMORY if out-of-memory
* or buffer limit reached.
*
*********************************************************************/
jb_err add_to_iob(struct client_state *csp, char *buf, long n)
{
struct iob *iob = csp->iob;
size_t used, offset, need, want;
char *p;
if (n <= 0) return JB_ERR_OK;
used = (size_t)(iob->eod - iob->buf);
offset = (size_t)(iob->cur - iob->buf);
need = used + (size_t)n + 1;
/*
* If the buffer can't hold the new data, extend it first.
* Use the next power of two if possible, else use the actual need.
*/
if (need > csp->config->buffer_limit)
{
log_error(LOG_LEVEL_INFO,
"Buffer limit reached while extending the buffer (iob). Needed: %d. Limit: %d",
need, csp->config->buffer_limit);
return JB_ERR_MEMORY;
}
if (need > iob->size)
{
for (want = csp->iob->size ? csp->iob->size : 512; want <= need;) want *= 2;
if (want <= csp->config->buffer_limit && NULL != (p = (char *)realloc(iob->buf, want)))
{
iob->size = want;
}
else if (NULL != (p = (char *)realloc(iob->buf, need)))
{
iob->size = need;
}
else
{
log_error(LOG_LEVEL_ERROR, "Extending the buffer (iob) failed: %E");
return JB_ERR_MEMORY;
}
/* Update the iob pointers */
iob->cur = p + offset;
iob->eod = p + used;
iob->buf = p;
}
/* copy the new data into the iob buffer */
memcpy(iob->eod, buf, (size_t)n);
/* point to the end of the data */
iob->eod += n;
/* null terminate == cheap insurance */
*iob->eod = '\0';
return JB_ERR_OK;
}
#ifdef FEATURE_ZLIB
/*********************************************************************
*
* Function : decompress_iob
*
* Description : Decompress buffered page, expanding the
* buffer as necessary. csp->iob->cur
* should point to the the beginning of the
* compressed data block.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success,
* JB_ERR_MEMORY if out-of-memory limit reached, and
* JB_ERR_COMPRESS if error decompressing buffer.
*
*********************************************************************/
jb_err decompress_iob(struct client_state *csp)
{
char *buf; /* new, uncompressed buffer */
char *cur; /* Current iob position (to keep the original
* iob->cur unmodified if we return early) */
size_t bufsize; /* allocated size of the new buffer */
size_t old_size; /* Content size before decompression */
size_t skip_size; /* Number of bytes at the beginning of the iob
that we should NOT decompress. */
int status; /* return status of the inflate() call */
z_stream zstr; /* used by calls to zlib */
assert(csp->iob->cur - csp->iob->buf > 0);
assert(csp->iob->eod - csp->iob->cur > 0);
bufsize = csp->iob->size;
skip_size = (size_t)(csp->iob->cur - csp->iob->buf);
old_size = (size_t)(csp->iob->eod - csp->iob->cur);
cur = csp->iob->cur;
if (bufsize < (size_t)10)
{
/*
* This is to protect the parsing of gzipped data,
* but it should(?) be valid for deflated data also.
*/
log_error(LOG_LEVEL_ERROR, "Buffer too small decompressing iob");
return JB_ERR_COMPRESS;
}
if (csp->content_type & CT_GZIP)
{
/*
* Our task is slightly complicated by the facts that data
* compressed by gzip does not include a zlib header, and
* that there is no easily accessible interface in zlib to
* handle a gzip header. We strip off the gzip header by
* hand, and later inform zlib not to expect a header.
*/
/*
* Strip off the gzip header. Please see RFC 1952 for more
* explanation of the appropriate fields.
*/
if ((*cur++ != (char)0x1f)
|| (*cur++ != (char)0x8b)
|| (*cur++ != Z_DEFLATED))
{
log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
return JB_ERR_COMPRESS;
}
else
{
int flags = *cur++;
/*
* XXX: These magic numbers should be replaced
* with macros to give a better idea what they do.
*/
if (flags & 0xe0)
{
/* The gzip header has reserved bits set; bail out. */
log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
return JB_ERR_COMPRESS;
}
cur += 6;
/* Skip extra fields if necessary. */
if (flags & 0x04)
{
/*
* Skip a given number of bytes, specified
* as a 16-bit little-endian value.
*/
/*
* XXX: This code used to be:
*
* csp->iob->cur += *csp->iob->cur++ + (*csp->iob->cur++ << 8);
*
* which I had to change into:
*
* cur += *cur++ + (*cur++ << 8);
*
* at which point gcc43 finally noticed that the value
* of cur is undefined (it depends on which of the
* summands is evaluated first).
*
* I haven't come across a site where this
* code is actually executed yet, but I hope
* it works anyway.
*/
int skip_bytes;
skip_bytes = *cur++;
skip_bytes = *cur++ << 8;
assert(skip_bytes == *csp->iob->cur - 2 + ((*csp->iob->cur - 1) << 8));
/*
* The number of bytes to skip should be positive
* and we'd like to stay in the buffer.
*/
if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
{
log_error(LOG_LEVEL_ERROR,
"Unreasonable amount of bytes to skip (%d). Stopping decompression",
skip_bytes);
return JB_ERR_COMPRESS;
}
log_error(LOG_LEVEL_INFO,
"Skipping %d bytes for gzip compression. Does this sound right?",
skip_bytes);
cur += skip_bytes;
}
/* Skip the filename if necessary. */
if (flags & 0x08)
{
/* A null-terminated string is supposed to follow. */
while (*cur++ && (cur < csp->iob->eod));
}
/* Skip the comment if necessary. */
if (flags & 0x10)
{
/* A null-terminated string is supposed to follow. */
while (*cur++ && (cur < csp->iob->eod));
}
/* Skip the CRC if necessary. */
if (flags & 0x02)
{
cur += 2;
}
if (cur >= csp->iob->eod)
{
/*
* If the current position pointer reached or passed
* the buffer end, we were obviously tricked to skip
* too much.
*/
log_error(LOG_LEVEL_ERROR,
"Malformed gzip header detected. Aborting decompression.");
return JB_ERR_COMPRESS;
}
}
}
else if (csp->content_type & CT_DEFLATE)
{
/*
* XXX: The debug level should be lowered
* before the next stable release.
*/
log_error(LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur);
/*
* In theory (that is, according to RFC 1950), deflate-compressed
* data should begin with a two-byte zlib header and have an
* adler32 checksum at the end. It seems that in practice only
* the raw compressed data is sent. Note that this means that
* we are not RFC 1950-compliant here, but the advantage is that
* this actually works. :)
*
* We add a dummy null byte to tell zlib where the data ends,
* and later inform it not to expect a header.
*
* Fortunately, add_to_iob() has thoughtfully null-terminated
* the buffer; we can just increment the end pointer to include
* the dummy byte.
*/
csp->iob->eod++;
}
else
{
log_error(LOG_LEVEL_ERROR,
"Unable to determine compression format for decompression");
return JB_ERR_COMPRESS;
}
/* Set up the fields required by zlib. */
zstr.next_in = (Bytef *)cur;
zstr.avail_in = (unsigned int)(csp->iob->eod - cur);
zstr.zalloc = Z_NULL;
zstr.zfree = Z_NULL;
zstr.opaque = Z_NULL;
/*
* Passing -MAX_WBITS to inflateInit2 tells the library
* that there is no zlib header.
*/
if (inflateInit2 (&zstr, -MAX_WBITS) != Z_OK)
{
log_error(LOG_LEVEL_ERROR, "Error initializing decompression");
return JB_ERR_COMPRESS;
}
/*
* Next, we allocate new storage for the inflated data.
* We don't modify the existing iob yet, so in case there
* is error in decompression we can recover gracefully.
*/
buf = zalloc(bufsize);
if (NULL == buf)
{
log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
return JB_ERR_MEMORY;
}
assert(bufsize >= skip_size);
memcpy(buf, csp->iob->buf, skip_size);
zstr.avail_out = bufsize - skip_size;
zstr.next_out = (Bytef *)buf + skip_size;
/* Try to decompress the whole stream in one shot. */
while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH)))
{
/* We need to allocate more memory for the output buffer. */
char *tmpbuf; /* used for realloc'ing the buffer */
size_t oldbufsize = bufsize; /* keep track of the old bufsize */
/*
* If zlib wants more data then there's a problem, because
* the complete compressed file should have been buffered.
*/
if (0 == zstr.avail_in)
{
log_error(LOG_LEVEL_ERROR, "Unexpected end of compressed iob");
return JB_ERR_COMPRESS;
}
/*
* If we tried the limit and still didn't have enough
* memory, just give up.
*/
if (bufsize == csp->config->buffer_limit)
{
log_error(LOG_LEVEL_ERROR, "Buffer limit reached while decompressing iob");
return JB_ERR_MEMORY;
}
/* Try doubling the buffer size each time. */
bufsize *= 2;
/* Don't exceed the buffer limit. */
if (bufsize > csp->config->buffer_limit)
{
bufsize = csp->config->buffer_limit;
}
/* Try to allocate the new buffer. */
tmpbuf = realloc(buf, bufsize);
if (NULL == tmpbuf)
{
log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
freez(buf);
return JB_ERR_MEMORY;
}
else
{
char *oldnext_out = (char *)zstr.next_out;
/*
* Update the fields for inflate() to use the new
* buffer, which may be in a location different from
* the old one.
*/
zstr.avail_out += bufsize - oldbufsize;
zstr.next_out = (Bytef *)tmpbuf + bufsize - zstr.avail_out;
/*
* Compare with an uglier method of calculating these values
* that doesn't require the extra oldbufsize variable.
*/
assert(zstr.avail_out == tmpbuf + bufsize - (char *)zstr.next_out);
assert((char *)zstr.next_out == tmpbuf + ((char *)oldnext_out - buf));
assert(zstr.avail_out > 0U);
buf = tmpbuf;
}
}
if (Z_STREAM_ERROR == inflateEnd(&zstr))
{
log_error(LOG_LEVEL_ERROR,
"Inconsistent stream state after decompression: %s", zstr.msg);
/*
* XXX: Intentionally no return.
*
* According to zlib.h, Z_STREAM_ERROR is returned
* "if the stream state was inconsistent".
*
* I assume in this case inflate()'s status
* would also be something different than Z_STREAM_END
* so this check should be redundant, but lets see.
*/
}
if (status != Z_STREAM_END)
{
/* We failed to decompress the stream. */
log_error(LOG_LEVEL_ERROR,
"Error in decompressing to the buffer (iob): %s", zstr.msg);
return JB_ERR_COMPRESS;
}
/*
* Finally, we can actually update the iob, since the
* decompression was successful. First, free the old
* buffer.
*/
freez(csp->iob->buf);
/* Now, update the iob to use the new buffer. */
csp->iob->buf = buf;
csp->iob->cur = csp->iob->buf + skip_size;
csp->iob->eod = (char *)zstr.next_out;
csp->iob->size = bufsize;
/*
* Make sure the new uncompressed iob obeys some minimal
* consistency conditions.
*/
if ((csp->iob->buf < csp->iob->cur)
&& (csp->iob->cur <= csp->iob->eod)
&& (csp->iob->eod <= csp->iob->buf + csp->iob->size))
{
const size_t new_size = (size_t)(csp->iob->eod - csp->iob->cur);
if (new_size > (size_t)0)
{
log_error(LOG_LEVEL_RE_FILTER,
"Decompression successful. Old size: %d, new size: %d.",
old_size, new_size);
}
else
{
/* zlib thinks this is OK, so lets do the same. */
log_error(LOG_LEVEL_INFO, "Decompression didn't result in any content.");
}
}
else
{
/* It seems that zlib did something weird. */
log_error(LOG_LEVEL_ERROR,
"Unexpected error decompressing the buffer (iob): %d==%d, %d>%d, %d<%d",
csp->iob->cur, csp->iob->buf + skip_size, csp->iob->eod, csp->iob->buf,
csp->iob->eod, csp->iob->buf + csp->iob->size);
return JB_ERR_COMPRESS;
}
return JB_ERR_OK;
}
#endif /* defined(FEATURE_ZLIB) */
/*********************************************************************
*
* Function : string_move
*
* Description : memmove wrapper to move the last part of a string
* towards the beginning, overwriting the part in
* the middle. strlcpy() can't be used here as the
* strings overlap.
*
* Parameters :
* 1 : dst = Destination to overwrite
* 2 : src = Source to move.
*
* Returns : N/A
*
*********************************************************************/
static void string_move(char *dst, char *src)
{
assert(dst < src);
/* +1 to copy the terminating nul as well. */
memmove(dst, src, strlen(src)+1);
}
/*********************************************************************
*
* Function : normalize_lws
*
* Description : Reduces unquoted linear white space in headers
* to a single space in accordance with RFC 2616 2.2.
* This simplifies parsing and filtering later on.
*
* XXX: Remove log messages before
* the next stable release?
*
* Parameters :
* 1 : header = A header with linear white space to reduce.
*
* Returns : N/A
*
*********************************************************************/
static void normalize_lws(char *header)
{
char *p = header;
while (*p != '\0')
{
if (ijb_isspace(*p) && ijb_isspace(*(p+1)))
{
char *q = p+1;
while (ijb_isspace(*q))
{
q++;
}
log_error(LOG_LEVEL_HEADER, "Reducing white space in '%s'", header);
string_move(p+1, q);
}
if (*p == '\t')
{
log_error(LOG_LEVEL_HEADER,
"Converting tab to space in '%s'", header);
*p = ' ';
}
else if (*p == '"')
{
char *end_of_token = strstr(p+1, "\"");
if (NULL != end_of_token)
{
/* Don't mess with quoted text. */
p = end_of_token;
}
else
{
log_error(LOG_LEVEL_HEADER,
"Ignoring single quote in '%s'", header);
}
}
p++;
}
p = strchr(header, ':');
if ((p != NULL) && (p != header) && ijb_isspace(*(p-1)))
{
/*
* There's still space before the colon.
* We don't want it.
*/
string_move(p-1, p);
}
}
/*********************************************************************
*
* Function : get_header
*
* Description : This (odd) routine will parse the csp->iob
* to get the next complete header.
*
* Parameters :
* 1 : iob = The I/O buffer to parse, usually csp->iob.
*
* Returns : Any one of the following:
*
* 1) a pointer to a dynamically allocated string that contains a header line
* 2) NULL indicating that the end of the header was reached
* 3) "" indicating that the end of the iob was reached before finding
* a complete header line.
*
*********************************************************************/
char *get_header(struct iob *iob)
{
char *header;
header = get_header_line(iob);
if ((header == NULL) || (*header == '\0'))
{
/*
* No complete header read yet, tell the client.
*/
return header;
}
while ((iob->cur[0] == ' ') || (iob->cur[0] == '\t'))
{
/*
* Header spans multiple lines, append the next one.
*/
char *continued_header;
continued_header = get_header_line(iob);
if ((continued_header == NULL) || (*continued_header == '\0'))
{
/*
* No complete header read yet, return what we got.
* XXX: Should "unread" header instead.
*/
log_error(LOG_LEVEL_INFO,
"Failed to read a multi-line header properly: '%s'",
header);
break;
}
if (JB_ERR_OK != string_join(&header, continued_header))
{
log_error(LOG_LEVEL_FATAL,
"Out of memory while appending multiple headers.");
}
else
{
/* XXX: remove before next stable release. */
log_error(LOG_LEVEL_HEADER,
"Merged multiple header lines to: '%s'",
header);
}
}
normalize_lws(header);
return header;
}
/*********************************************************************
*
* Function : get_header_line
*
* Description : This (odd) routine will parse the csp->iob
* to get the next header line.
*
* Parameters :
* 1 : iob = The I/O buffer to parse, usually csp->iob.
*
* Returns : Any one of the following:
*
* 1) a pointer to a dynamically allocated string that contains a header line
* 2) NULL indicating that the end of the header was reached
* 3) "" indicating that the end of the iob was reached before finding
* a complete header line.
*
*********************************************************************/
static char *get_header_line(struct iob *iob)
{
char *p, *q, *ret;
if ((iob->cur == NULL)
|| ((p = strchr(iob->cur, '\n')) == NULL))
{
return(""); /* couldn't find a complete header */
}
*p = '\0';
ret = strdup(iob->cur);
if (ret == NULL)
{
/* FIXME No way to handle error properly */
log_error(LOG_LEVEL_FATAL, "Out of memory in get_header_line()");
}
assert(ret != NULL);
iob->cur = p+1;
if ((q = strchr(ret, '\r')) != NULL) *q = '\0';
/* is this a blank line (i.e. the end of the header) ? */
if (*ret == '\0')
{
freez(ret);
return NULL;
}
return ret;
}
/*********************************************************************
*
* Function : get_header_value
*
* Description : Get the value of a given header from a chained list
* of header lines or return NULL if no such header is
* present in the list.
*
* Parameters :
* 1 : header_list = pointer to list
* 2 : header_name = string with name of header to look for.
* Trailing colon required, capitalization
* doesn't matter.
*
* Returns : NULL if not found, else value of header
*
*********************************************************************/
char *get_header_value(const struct list *header_list, const char *header_name)
{
struct list_entry *cur_entry;
char *ret = NULL;
size_t length = 0;
assert(header_list);
assert(header_name);
length = strlen(header_name);
for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next)
{
if (cur_entry->str)
{
if (!strncmpic(cur_entry->str, header_name, length))
{
/*
* Found: return pointer to start of value
*/
ret = cur_entry->str + length;
while (*ret && ijb_isspace(*ret)) ret++;
return ret;
}
}
}
/*
* Not found
*/
return NULL;
}
/*********************************************************************
*
* Function : scan_headers
*
* Description : Scans headers, applies tags and updates action bits.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK
*
*********************************************************************/
static jb_err scan_headers(struct client_state *csp)
{
struct list_entry *h; /* Header */
jb_err err = JB_ERR_OK;
for (h = csp->headers->first; (err == JB_ERR_OK) && (h != NULL) ; h = h->next)
{
/* Header crunch()ed in previous run? -> ignore */
if (h->str == NULL) continue;
log_error(LOG_LEVEL_HEADER, "scan: %s", h->str);
err = header_tagger(csp, h->str);
}
return err;
}
/*********************************************************************
*
* Function : sed
*
* Description : add, delete or modify lines in the HTTP header streams.
* On entry, it receives a linked list of headers space
* that was allocated dynamically (both the list nodes
* and the header contents).
*
* As a side effect it frees the space used by the original
* header lines.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : filter_server_headers = Boolean to switch between
* server and header filtering.
*
* Returns : JB_ERR_OK in case off success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
jb_err sed(struct client_state *csp, int filter_server_headers)
{
/* XXX: use more descriptive names. */
struct list_entry *p;
const struct parsers *v;
const add_header_func_ptr *f;
jb_err err = JB_ERR_OK;
if (filter_server_headers)
{
v = server_patterns;
f = add_server_headers;
}
else
{
v = client_patterns;
f = add_client_headers;
}
scan_headers(csp);
while ((err == JB_ERR_OK) && (v->str != NULL))
{
for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
{
/* Header crunch()ed in previous run? -> ignore */
if (p->str == NULL) continue;
/* Does the current parser handle this header? */
if ((strncmpic(p->str, v->str, v->len) == 0) ||
(v->len == CHECK_EVERY_HEADER_REMAINING))
{
err = v->parser(csp, &(p->str));
}
}
v++;
}
/* place additional headers on the csp->headers list */
while ((err == JB_ERR_OK) && (*f))
{
err = (*f)(csp);
f++;
}
return err;
}
/*********************************************************************
*
* Function : update_server_headers
*
* Description : Updates server headers after the body has been modified.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK in case off success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
jb_err update_server_headers(struct client_state *csp)
{
jb_err err = JB_ERR_OK;
static const struct parsers server_patterns_light[] = {
{ "Content-Length:", 15, server_adjust_content_length },
{ "Transfer-Encoding:", 18, server_transfer_coding },
#ifdef FEATURE_ZLIB
{ "Content-Encoding:", 17, server_content_encoding },
#endif /* def FEATURE_ZLIB */
{ NULL, 0, NULL }
};
if (strncmpic(csp->http->cmd, "HEAD", 4))
{
const struct parsers *v;
struct list_entry *p;
for (v = server_patterns_light; (err == JB_ERR_OK) && (v->str != NULL); v++)
{
for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
{
/* Header crunch()ed in previous run? -> ignore */
if (p->str == NULL) continue;
/* Does the current parser handle this header? */
if (strncmpic(p->str, v->str, v->len) == 0)
{
err = v->parser(csp, (char **)&(p->str));
}
}
}
}
return err;
}
/*********************************************************************
*
* Function : header_tagger
*
* Description : Executes all text substitutions from applying
* tag actions and saves the result as tag.
*
* XXX: Shares enough code with filter_header() and
* pcrs_filter_response() to warrant some helper functions.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = Header that is used as tagger input
*
* Returns : JB_ERR_OK on success and always succeeds
*
*********************************************************************/
static jb_err header_tagger(struct client_state *csp, char *header)
{
int wanted_filter_type;
int multi_action_index;
int i;
pcrs_job *job;
struct file_list *fl;
struct re_filterfile_spec *b;
struct list_entry *tag_name;
int found_filters = 0;
const size_t header_length = strlen(header);
if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
{
wanted_filter_type = FT_SERVER_HEADER_TAGGER;
multi_action_index = ACTION_MULTI_SERVER_HEADER_TAGGER;
}
else
{
wanted_filter_type = FT_CLIENT_HEADER_TAGGER;
multi_action_index = ACTION_MULTI_CLIENT_HEADER_TAGGER;
}
/* Check if there are any filters */
for (i = 0; i < MAX_AF_FILES; i++)
{
fl = csp->rlist[i];
if (NULL != fl)
{
if (NULL != fl->f)
{
found_filters = 1;
break;
}
}
}
if (0 == found_filters)
{
log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
"tagging enabled, but no taggers available.");
return JB_ERR_OK;
}
for (i = 0; i < MAX_AF_FILES; i++)
{
fl = csp->rlist[i];
if ((NULL == fl) || (NULL == fl->f))
{
/*
* Either there are no filter files
* left, or this filter file just
* contains no valid filters.
*
* Continue to be sure we don't miss
* valid filter files that are chained
* after empty or invalid ones.
*/
continue;
}
/* For all filters, */
for (b = fl->f; b; b = b->next)
{
if (b->type != wanted_filter_type)
{
/* skip the ones we don't care about, */
continue;
}
/* leaving only taggers that could apply, of which we use the ones, */
for (tag_name = csp->action->multi[multi_action_index]->first;
NULL != tag_name; tag_name = tag_name->next)
{
/* that do apply, and */
if (strcmp(b->name, tag_name->str) == 0)
{
char *modified_tag = NULL;
char *tag = header;
size_t size = header_length;
pcrs_job *joblist = b->joblist;
if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
if (NULL == joblist)
{
log_error(LOG_LEVEL_RE_FILTER,
"Tagger %s has empty joblist. Nothing to do.", b->name);
continue;
}
/* execute their pcrs_joblist on the header. */
for (job = joblist; NULL != job; job = job->next)
{
const int hits = pcrs_execute(job, tag, size, &modified_tag, &size);
if (0 < hits)
{
/* Success, continue with the modified version. */
if (tag != header)
{
freez(tag);
}
tag = modified_tag;
}
else
{
/* Tagger doesn't match */
if (0 > hits)
{
/* Regex failure, log it but continue anyway. */
assert(NULL != header);
log_error(LOG_LEVEL_ERROR,
"Problems with tagger \'%s\' and header \'%s\': %s",
b->name, *header, pcrs_strerror(hits));
}
freez(modified_tag);
}
}
if (b->dynamic) pcrs_free_joblist(joblist);
/* If this tagger matched */
if (tag != header)
{
if (0 == size)
{
/*
* There is to technical limitation which makes
* it impossible to use empty tags, but I assume
* no one would do it intentionally.
*/
freez(tag);
log_error(LOG_LEVEL_INFO,
"Tagger \'%s\' created an empty tag. Ignored.",
b->name);
continue;
}
if (!list_contains_item(csp->tags, tag))
{
if (JB_ERR_OK != enlist(csp->tags, tag))
{
log_error(LOG_LEVEL_ERROR,
"Insufficient memory to add tag \'%s\', "
"based on tagger \'%s\' and header \'%s\'",
tag, b->name, *header);
}
else
{
char *action_message;
/*
* update the action bits right away, to make
* tagging based on tags set by earlier taggers
* of the same kind possible.
*/
if (update_action_bits_for_tag(csp, tag))
{
action_message = "Action bits updated accordingly.";
}
else
{
action_message = "No action bits update necessary.";
}
log_error(LOG_LEVEL_HEADER,
"Tagger \'%s\' added tag \'%s\'. %s",
b->name, tag, action_message);
}
}
else
{
/* XXX: Is this log-worthy? */
log_error(LOG_LEVEL_HEADER,
"Tagger \'%s\' didn't add tag \'%s\'. "
"Tag already present", b->name, tag);
}
freez(tag);
} /* if the tagger matched */
} /* if the tagger applies */
} /* for every tagger that could apply */
} /* for all filters */
} /* for all filter files */
return JB_ERR_OK;
}
/* here begins the family of parser functions that reformat header lines */
/*********************************************************************
*
* Function : filter_header
*
* Description : Executes all text substitutions from all applying
* +(server|client)-header-filter actions on the header.
* Most of the code was copied from pcrs_filter_response,
* including the rather short variable names
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success and always succeeds
*
*********************************************************************/
static jb_err filter_header(struct client_state *csp, char **header)
{
int hits=0;
int matches;
size_t size = strlen(*header);
char *newheader = NULL;
pcrs_job *job;
struct file_list *fl;
struct re_filterfile_spec *b;
struct list_entry *filtername;
int i, found_filters = 0;
int wanted_filter_type;
int multi_action_index;
if (csp->flags & CSP_FLAG_NO_FILTERING)
{
return JB_ERR_OK;
}
if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
{
wanted_filter_type = FT_SERVER_HEADER_FILTER;
multi_action_index = ACTION_MULTI_SERVER_HEADER_FILTER;
}
else
{
wanted_filter_type = FT_CLIENT_HEADER_FILTER;
multi_action_index = ACTION_MULTI_CLIENT_HEADER_FILTER;
}
/*
* Need to check the set of re_filterfiles...
*/
for (i = 0; i < MAX_AF_FILES; i++)
{
fl = csp->rlist[i];
if (NULL != fl)
{
if (NULL != fl->f)
{
found_filters = 1;
break;
}
}
}
if (0 == found_filters)
{
log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
"header filtering enabled, but no matching filters available.");
return JB_ERR_OK;
}
for (i = 0; i < MAX_AF_FILES; i++)
{
fl = csp->rlist[i];
if ((NULL == fl) || (NULL == fl->f))
{
/*
* Either there are no filter files
* left, or this filter file just
* contains no valid filters.
*
* Continue to be sure we don't miss
* valid filter files that are chained
* after empty or invalid ones.
*/
continue;
}
/*
* For all applying +filter actions, look if a filter by that
* name exists and if yes, execute its pcrs_joblist on the
* buffer.
*/
for (b = fl->f; b; b = b->next)
{
if (b->type != wanted_filter_type)
{
/* Skip other filter types */
continue;
}
for (filtername = csp->action->multi[multi_action_index]->first;
filtername ; filtername = filtername->next)
{
if (strcmp(b->name, filtername->str) == 0)
{
int current_hits = 0;
pcrs_job *joblist = b->joblist;
if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
if (NULL == joblist)
{
log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
continue;
}
log_error(LOG_LEVEL_RE_FILTER, "filtering \'%s\' (size %d) with \'%s\' ...",
*header, size, b->name);
/* Apply all jobs from the joblist */
for (job = joblist; NULL != job; job = job->next)
{
matches = pcrs_execute(job, *header, size, &newheader, &size);
if ( 0 < matches )
{
current_hits += matches;
log_error(LOG_LEVEL_HEADER, "Transforming \"%s\" to \"%s\"", *header, newheader);
freez(*header);
*header = newheader;
}
else if ( 0 == matches )
{
/* Filter doesn't change header */
freez(newheader);
}
else
{
/* RegEx failure */
log_error(LOG_LEVEL_ERROR, "Filtering \'%s\' with \'%s\' didn't work out: %s",
*header, b->name, pcrs_strerror(matches));
if (newheader != NULL)
{
log_error(LOG_LEVEL_ERROR, "Freeing what's left: %s", newheader);
freez(newheader);
}
}
}
if (b->dynamic) pcrs_free_joblist(joblist);
log_error(LOG_LEVEL_RE_FILTER, "... produced %d hits (new size %d).", current_hits, size);
hits += current_hits;
}
}
}
}
/*
* Additionally checking for hits is important because if
* the continue hack is triggered, server headers can
* arrive empty to separate multiple heads from each other.
*/
if ((0 == size) && hits)
{
log_error(LOG_LEVEL_HEADER, "Removing empty header %s", *header);
freez(*header);
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_connection
*
* Description : Makes sure that the value of the Connection: header
* is "close" and signals server_connection_close_adder
* to do nothing.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_connection(struct client_state *csp, char **header)
{
char *old_header = *header;
/* Do we have a 'Connection: close' header? */
if (strcmpic(*header, "Connection: close"))
{
#ifdef FEATURE_CONNECTION_KEEP_ALIVE
if ((csp->config->feature_flags &
RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
&& !strcmpic(*header, "Connection: keep-alive"))
{
/* Remember to keep the connection alive. */
csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
}
#endif /* FEATURE_CONNECTION_KEEP_ALIVE */
*header = strdup("Connection: close");
if (header == NULL)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "Replaced: \'%s\' with \'%s\'", old_header, *header);
freez(old_header);
}
/* Signal server_connection_close_adder() to return early. */
csp->flags |= CSP_FLAG_SERVER_CONNECTION_CLOSE_SET;
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_connection
*
* Description : Makes sure a proper "Connection:" header is
* set and signals connection_header_adder
* to do nothing.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_connection(struct client_state *csp, char **header)
{
char *old_header = *header;
const char *wanted_header = get_appropiate_connection_header(csp);
if (strcmpic(*header, wanted_header))
{
*header = strdup(wanted_header);
if (header == NULL)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER,
"Replaced: \'%s\' with \'%s\'", old_header, *header);
freez(old_header);
}
/* Signal client_connection_close_adder() to return early. */
csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET;
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : crumble
*
* Description : This is called if a header matches a pattern to "crunch"
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err crumble(struct client_state *csp, char **header)
{
(void)csp;
log_error(LOG_LEVEL_HEADER, "crumble crunched: %s!", *header);
freez(*header);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : crunch_server_header
*
* Description : Crunch server header if it matches a string supplied by the
* user. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success and always succeeds
*
*********************************************************************/
static jb_err crunch_server_header(struct client_state *csp, char **header)
{
const char *crunch_pattern;
/* Do we feel like crunching? */
if ((csp->action->flags & ACTION_CRUNCH_SERVER_HEADER))
{
crunch_pattern = csp->action->string[ACTION_STRING_SERVER_HEADER];
/* Is the current header the lucky one? */
if (strstr(*header, crunch_pattern))
{
log_error(LOG_LEVEL_HEADER, "Crunching server header: %s (contains: %s)", *header, crunch_pattern);
freez(*header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_content_type
*
* Description : Set the content-type for filterable types (text/.*,
* .*xml.*, javascript and image/gif) unless filtering has been
* forbidden (CT_TABOO) while parsing earlier headers.
* NOTE: Since text/plain is commonly used by web servers
* for files whose correct type is unknown, we don't
* set CT_TEXT for it.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_content_type(struct client_state *csp, char **header)
{
/* Remove header if it isn't the first Content-Type header */
if ((csp->content_type & CT_DECLARED))
{
/*
* Another, slightly slower, way to see if
* we already parsed another Content-Type header.
*/
assert(NULL != get_header_value(csp->headers, "Content-Type:"));
log_error(LOG_LEVEL_ERROR,
"Multiple Content-Type headers. Removing and ignoring: \'%s\'",
*header);
freez(*header);
return JB_ERR_OK;
}
/*
* Signal that the Content-Type has been set.
*/
csp->content_type |= CT_DECLARED;
if (!(csp->content_type & CT_TABOO))
{
/*
* XXX: The assumption that text/plain is a sign of
* binary data seems to be somewhat unreasonable nowadays
* and should be dropped after 3.0.8 is out.
*/
if ((strstr(*header, "text/") && !strstr(*header, "plain"))
|| strstr(*header, "xml")
|| strstr(*header, "application/x-javascript"))
{
csp->content_type |= CT_TEXT;
}
else if (strstr(*header, "image/gif"))
{
csp->content_type |= CT_GIF;
}
}
/*
* Are we messing with the content type?
*/
if (csp->action->flags & ACTION_CONTENT_TYPE_OVERWRITE)
{
/*
* Make sure the user doesn't accidently
* change the content type of binary documents.
*/
if ((csp->content_type & CT_TEXT) || (csp->action->flags & ACTION_FORCE_TEXT_MODE))
{
freez(*header);
*header = strdup("Content-Type: ");
string_append(header, csp->action->string[ACTION_STRING_CONTENT_TYPE]);
if (header == NULL)
{
log_error(LOG_LEVEL_HEADER, "Insufficient memory to replace Content-Type!");
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "Modified: %s!", *header);
}
else
{
log_error(LOG_LEVEL_HEADER, "%s not replaced. "
"It doesn't look like a content type that should be filtered. "
"Enable force-text-mode if you know what you're doing.", *header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_transfer_coding
*
* Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses
* - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked"
* - Remove header if body was chunked but has been
* de-chunked for filtering.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_transfer_coding(struct client_state *csp, char **header)
{
/*
* Turn off pcrs and gif filtering if body compressed
*/
if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
{
#ifdef FEATURE_ZLIB
/*
* XXX: Added to test if we could use CT_GZIP and CT_DEFLATE here.
*/
log_error(LOG_LEVEL_INFO, "Marking content type for %s as CT_TABOO because of %s.",
csp->http->cmd, *header);
#endif /* def FEATURE_ZLIB */
csp->content_type = CT_TABOO;
}
/*
* Raise flag if body chunked
*/
if (strstr(*header, "chunked"))
{
csp->flags |= CSP_FLAG_CHUNKED;
/*
* If the body was modified, it has been de-chunked first
* and the header must be removed.
*
* FIXME: If there is more than one transfer encoding,
* only the "chunked" part should be removed here.
*/
if (csp->flags & CSP_FLAG_MODIFIED)
{
log_error(LOG_LEVEL_HEADER, "Removing: %s", *header);
freez(*header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_content_encoding
*
* Description : This function is run twice for each request,
* unless FEATURE_ZLIB and filtering are disabled.
*
* The first run is used to check if the content
* is compressed, if FEATURE_ZLIB is disabled
* filtering is then disabled as well, if FEATURE_ZLIB
* is enabled the content is marked for decompression.
*
* The second run is used to remove the Content-Encoding
* header if the decompression was successful.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_content_encoding(struct client_state *csp, char **header)
{
#ifdef FEATURE_ZLIB
if ((csp->flags & CSP_FLAG_MODIFIED)
&& (csp->content_type & (CT_GZIP | CT_DEFLATE)))
{
/*
* We successfully decompressed the content,
* and have to clean the header now, so the
* client no longer expects compressed data..
*
* XXX: There is a difference between cleaning
* and removing it completely.
*/
log_error(LOG_LEVEL_HEADER, "Crunching: %s", *header);
freez(*header);
}
else if (strstr(*header, "gzip"))
{
/* Mark for gzip decompression */
csp->content_type |= CT_GZIP;
}
else if (strstr(*header, "deflate"))
{
/* Mark for zlib decompression */
csp->content_type |= CT_DEFLATE;
}
else if (strstr(*header, "compress"))
{
/*
* We can't decompress this; therefore we can't filter
* it either.
*/
csp->content_type |= CT_TABOO;
}
#else /* !defined(FEATURE_ZLIB) */
if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
{
/*
* Body is compressed, turn off pcrs and gif filtering.
*/
csp->content_type |= CT_TABOO;
/*
* Log a warning if the user expects the content to be filtered.
*/
if ((csp->rlist != NULL) &&
(!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
{
log_error(LOG_LEVEL_INFO,
"Compressed content detected, content filtering disabled. "
"Consider recompiling Privoxy with zlib support or "
"enable the prevent-compression action.");
}
}
#endif /* defined(FEATURE_ZLIB) */
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_adjust_content_length
*
* Description : Adjust Content-Length header if we modified
* the body.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_adjust_content_length(struct client_state *csp, char **header)
{
const size_t max_header_length = 80;
/* Regenerate header if the content was modified. */
if (csp->flags & CSP_FLAG_MODIFIED)
{
freez(*header);
*header = (char *) zalloc(max_header_length);
if (*header == NULL)
{
return JB_ERR_MEMORY;
}
snprintf(*header, max_header_length, "Content-Length: %d",
(int)csp->content_length);
log_error(LOG_LEVEL_HEADER, "Adjusted Content-Length to %d",
(int)csp->content_length);
}
return JB_ERR_OK;
}
#ifdef FEATURE_CONNECTION_KEEP_ALIVE
/*********************************************************************
*
* Function : server_save_content_length
*
* Description : Save the Content-Length sent by the server.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_save_content_length(struct client_state *csp, char **header)
{
unsigned long long content_length = 0;
assert(*(*header+14) == ':');
if (1 != sscanf(*header+14, ": %llu", &content_length))
{
log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
freez(*header);
}
else
{
csp->expected_content_length = content_length;
csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
}
return JB_ERR_OK;
}
#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
/*********************************************************************
*
* Function : server_content_md5
*
* Description : Crumble any Content-MD5 headers if the document was
* modified. FIXME: Should we re-compute instead?
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_content_md5(struct client_state *csp, char **header)
{
if (csp->flags & CSP_FLAG_MODIFIED)
{
log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5");
freez(*header);
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_content_disposition
*
* Description : If enabled, blocks or modifies the "Content-Disposition" header.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_content_disposition(struct client_state *csp, char **header)
{
const char *newval;
/*
* Are we messing with the Content-Disposition header?
*/
if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0)
{
/* Me tinks not */
return JB_ERR_OK;
}
newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION];
if ((newval == NULL) || (0 == strcmpic(newval, "block")))
{
/*
* Blocking content-disposition header
*/
log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
freez(*header);
return JB_ERR_OK;
}
else
{
/*
* Replacing Content-Disposition header
*/
freez(*header);
*header = strdup("Content-Disposition: ");
string_append(header, newval);
if (*header != NULL)
{
log_error(LOG_LEVEL_HEADER,
"Content-Disposition header crunched and replaced with: %s", *header);
}
}
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_last_modified
*
* Description : Changes Last-Modified header to the actual date
* to help hide-if-modified-since.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_last_modified(struct client_state *csp, char **header)
{
const char *newval;
char buf[BUFFER_SIZE];
char newheader[50];
#ifdef HAVE_GMTIME_R
struct tm gmt;
#endif
struct tm *timeptr = NULL;
time_t now, last_modified;
long int rtime;
long int days, hours, minutes, seconds;
/*
* Are we messing with the Last-Modified header?
*/
if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0)
{
/*Nope*/
return JB_ERR_OK;
}
newval = csp->action->string[ACTION_STRING_LAST_MODIFIED];
if (0 == strcmpic(newval, "block") )
{
/*
* Blocking Last-Modified header. Useless but why not.
*/
log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
freez(*header);
return JB_ERR_OK;
}
else if (0 == strcmpic(newval, "reset-to-request-time"))
{
/*
* Setting Last-Modified Header to now.
*/
get_http_time(0, buf, sizeof(buf));
freez(*header);
*header = strdup("Last-Modified: ");
string_append(header, buf);
if (*header == NULL)
{
log_error(LOG_LEVEL_HEADER, "Insufficient memory. Last-Modified header got lost, boohoo.");
}
else
{
log_error(LOG_LEVEL_HEADER, "Reset to present time: %s", *header);
}
}
else if (0 == strcmpic(newval, "randomize"))
{
const char *header_time = *header + sizeof("Last-Modified:");
log_error(LOG_LEVEL_HEADER, "Randomizing: %s", *header);
now = time(NULL);
#ifdef HAVE_GMTIME_R
timeptr = gmtime_r(&now, &gmt);
#elif FEATURE_PTHREAD
privoxy_mutex_lock(&gmtime_mutex);
timeptr = gmtime(&now);
privoxy_mutex_unlock(&gmtime_mutex);
#else
timeptr = gmtime(&now);
#endif
if (JB_ERR_OK != parse_header_time(header_time, &last_modified))
{
log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
freez(*header);
}
else
{
rtime = (long int)difftime(now, last_modified);
if (rtime)
{
int negative = 0;
if (rtime < 0)
{
rtime *= -1;
negative = 1;
log_error(LOG_LEVEL_HEADER, "Server time in the future.");
}
rtime = pick_from_range(rtime);
if (negative) rtime *= -1;
last_modified += rtime;
#ifdef HAVE_GMTIME_R
timeptr = gmtime_r(&last_modified, &gmt);
#elif FEATURE_PTHREAD
privoxy_mutex_lock(&gmtime_mutex);
timeptr = gmtime(&last_modified);
privoxy_mutex_unlock(&gmtime_mutex);
#else
timeptr = gmtime(&last_modified);
#endif
strftime(newheader, sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr);
freez(*header);
*header = strdup("Last-Modified: ");
string_append(header, newheader);
if (*header == NULL)
{
log_error(LOG_LEVEL_ERROR, "Insufficient memory, header crunched without replacement.");
return JB_ERR_MEMORY;
}
days = rtime / (3600 * 24);
hours = rtime / 3600 % 24;
minutes = rtime / 60 % 60;
seconds = rtime % 60;
log_error(LOG_LEVEL_HEADER,
"Randomized: %s (added %d da%s %d hou%s %d minut%s %d second%s",
*header, days, (days == 1) ? "y" : "ys", hours, (hours == 1) ? "r" : "rs",
minutes, (minutes == 1) ? "e" : "es", seconds, (seconds == 1) ? ")" : "s)");
}
else
{
log_error(LOG_LEVEL_HEADER, "Randomized ... or not. No time difference to work with.");
}
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_accept_encoding
*
* Description : Rewrite the client's Accept-Encoding header so that
* if doesn't allow compression, if the action applies.
* Note: For HTTP/1.0 the absence of the header is enough.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_accept_encoding(struct client_state *csp, char **header)
{
if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
{
log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content");
freez(*header);
/* Temporarily disable the correct behaviour to
* work around a PHP bug.
*
* if (!strcmpic(csp->http->ver, "HTTP/1.1"))
* {
* *header = strdup("Accept-Encoding: identity;q=1.0, *;q=0");
* if (*header == NULL)
* {
* return JB_ERR_MEMORY;
* }
* }
*
*/
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_te
*
* Description : Rewrite the client's TE header so that
* if doesn't allow compression, if the action applies.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_te(struct client_state *csp, char **header)
{
if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
{
freez(*header);
log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress transfer");
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_referrer
*
* Description : Handle the "referer" config setting properly.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_referrer(struct client_state *csp, char **header)
{
const char *parameter;
/* booleans for parameters we have to check multiple times */
int parameter_conditional_block;
int parameter_conditional_forge;
#ifdef FEATURE_FORCE_LOAD
/*
* Since the referrer can include the prefix even
* if the request itself is non-forced, we must
* clean it unconditionally.
*
* XXX: strclean is too broad
*/
strclean(*header, FORCE_PREFIX);
#endif /* def FEATURE_FORCE_LOAD */
if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
{
/* Nothing left to do */
return JB_ERR_OK;
}
parameter = csp->action->string[ACTION_STRING_REFERER];
assert(parameter != NULL);
parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
if (!parameter_conditional_block && !parameter_conditional_forge)
{
/*
* As conditional-block and conditional-forge are the only
* parameters that rely on the original referrer, we can
* remove it now for all the others.
*/
freez(*header);
}
if (0 == strcmpic(parameter, "block"))
{
log_error(LOG_LEVEL_HEADER, "Referer crunched!");
return JB_ERR_OK;
}
else if (parameter_conditional_block || parameter_conditional_forge)
{
return handle_conditional_hide_referrer_parameter(header,
csp->http->hostport, parameter_conditional_block);
}
else if (0 == strcmpic(parameter, "forge"))
{
return create_forged_referrer(header, csp->http->hostport);
}
else
{
/* interpret parameter as user-supplied referer to fake */
return create_fake_referrer(header, parameter);
}
}
/*********************************************************************
*
* Function : client_accept_language
*
* Description : Handle the "Accept-Language" config setting properly.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_accept_language(struct client_state *csp, char **header)
{
const char *newval;
/*
* Are we messing with the Accept-Language?
*/
if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0)
{
/*I don't think so*/
return JB_ERR_OK;
}
newval = csp->action->string[ACTION_STRING_LANGUAGE];
if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
{
/*
* Blocking Accept-Language header
*/
log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!");
freez(*header);
return JB_ERR_OK;
}
else
{
/*
* Replacing Accept-Language header
*/
freez(*header);
*header = strdup("Accept-Language: ");
string_append(header, newval);
if (*header == NULL)
{
log_error(LOG_LEVEL_ERROR,
"Insufficient memory. Accept-Language header crunched without replacement.");
}
else
{
log_error(LOG_LEVEL_HEADER,
"Accept-Language header crunched and replaced with: %s", *header);
}
}
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
/*********************************************************************
*
* Function : crunch_client_header
*
* Description : Crunch client header if it matches a string supplied by the
* user. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success and always succeeds
*
*********************************************************************/
static jb_err crunch_client_header(struct client_state *csp, char **header)
{
const char *crunch_pattern;
/* Do we feel like crunching? */
if ((csp->action->flags & ACTION_CRUNCH_CLIENT_HEADER))
{
crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER];
/* Is the current header the lucky one? */
if (strstr(*header, crunch_pattern))
{
log_error(LOG_LEVEL_HEADER, "Crunching client header: %s (contains: %s)", *header, crunch_pattern);
freez(*header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_uagent
*
* Description : Handle the "user-agent" config setting properly
* and remember its original value to enable browser
* bug workarounds. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_uagent(struct client_state *csp, char **header)
{
const char *newval;
if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0)
{
return JB_ERR_OK;
}
newval = csp->action->string[ACTION_STRING_USER_AGENT];
if (newval == NULL)
{
return JB_ERR_OK;
}
freez(*header);
*header = strdup("User-Agent: ");
string_append(header, newval);
log_error(LOG_LEVEL_HEADER, "Modified: %s", *header);
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_ua
*
* Description : Handle "ua-" headers properly. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_ua(struct client_state *csp, char **header)
{
if ((csp->action->flags & ACTION_HIDE_USER_AGENT) != 0)
{
log_error(LOG_LEVEL_HEADER, "crunched User-Agent!");
freez(*header);
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_from
*
* Description : Handle the "from" config setting properly.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_from(struct client_state *csp, char **header)
{
const char *newval;
if ((csp->action->flags & ACTION_HIDE_FROM) == 0)
{
return JB_ERR_OK;
}
freez(*header);
newval = csp->action->string[ACTION_STRING_FROM];
/*
* Are we blocking the e-mail address?
*/
if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
{
log_error(LOG_LEVEL_HEADER, "crunched From!");
return JB_ERR_OK;
}
log_error(LOG_LEVEL_HEADER, " modified");
*header = strdup("From: ");
string_append(header, newval);
return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_send_cookie
*
* Description : Crunches the "cookie" header if necessary.
* Called from `sed'.
*
* XXX: Stupid name, doesn't send squat.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_send_cookie(struct client_state *csp, char **header)
{
if (csp->action->flags & ACTION_NO_COOKIE_READ)
{
log_error(LOG_LEVEL_HEADER, "Crunched outgoing cookie: %s", *header);
freez(*header);
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_x_forwarded
*
* Description : Handle the "x-forwarded-for" config setting properly,
* also used in the add_client_headers list. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
jb_err client_x_forwarded(struct client_state *csp, char **header)
{
if (0 != (csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR))
{
const char *parameter = csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR];
if (0 == strcmpic(parameter, "block"))
{
freez(*header);
log_error(LOG_LEVEL_HEADER, "crunched x-forwarded-for!");
}
else if (0 == strcmpic(parameter, "add"))
{
string_append(header, ", ");
string_append(header, csp->ip_addr_str);
if (*header == NULL)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER,
"Appended client IP address to %s", *header);
csp->flags |= CSP_FLAG_X_FORWARDED_FOR_APPENDED;
}
else
{
log_error(LOG_LEVEL_FATAL,
"Invalid change-x-forwarded-for parameter: '%s'", parameter);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_max_forwards
*
* Description : If the HTTP method is OPTIONS or TRACE, subtract one
* from the value of the Max-Forwards header field.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_max_forwards(struct client_state *csp, char **header)
{
int max_forwards;
if ((0 == strcmpic(csp->http->gpc, "trace")) ||
(0 == strcmpic(csp->http->gpc, "options")))
{
assert(*(*header+12) == ':');
if (1 == sscanf(*header+12, ": %d", &max_forwards))
{
if (max_forwards > 0)
{
snprintf(*header, strlen(*header)+1, "Max-Forwards: %d", --max_forwards);
log_error(LOG_LEVEL_HEADER,
"Max-Forwards value for %s request reduced to %d.",
csp->http->gpc, max_forwards);
}
else if (max_forwards < 0)
{
log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
freez(*header);
}
}
else
{
log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
freez(*header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_host
*
* Description : If the request URI did not contain host and
* port information, parse and evaluate the Host
* header field.
*
* Also, kill ill-formed HOST: headers as sent by
* Apple's iTunes software when used with a proxy.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_host(struct client_state *csp, char **header)
{
char *p, *q;
/*
* If the header field name is all upper-case, chances are that it's
* an ill-formed one from iTunes. BTW, killing innocent headers here is
* not a problem -- they are regenerated later.
*/
if ((*header)[1] == 'O')
{
log_error(LOG_LEVEL_HEADER, "Killed all-caps Host header line: %s", *header);
freez(*header);
return JB_ERR_OK;
}
if (!csp->http->hostport || (*csp->http->hostport == '*') ||
*csp->http->hostport == ' ' || *csp->http->hostport == '\0')
{
if (NULL == (p = strdup((*header)+6)))
{
return JB_ERR_MEMORY;
}
chomp(p);
if (NULL == (q = strdup(p)))
{
freez(p);
return JB_ERR_MEMORY;
}
freez(csp->http->hostport);
csp->http->hostport = p;
freez(csp->http->host);
csp->http->host = q;
q = strchr(csp->http->host, ':');
if (q != NULL)
{
/* Terminate hostname and evaluate port string */
*q++ = '\0';
csp->http->port = atoi(q);
}
else
{
csp->http->port = csp->http->ssl ? 443 : 80;
}
log_error(LOG_LEVEL_HEADER, "New host and port from Host field: %s = %s:%d",
csp->http->hostport, csp->http->host, csp->http->port);
}
/* Signal client_host_adder() to return right away */
csp->flags |= CSP_FLAG_HOST_HEADER_IS_SET;
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_if_modified_since
*
* Description : Remove or modify the If-Modified-Since header.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_if_modified_since(struct client_state *csp, char **header)
{
char newheader[50];
#ifdef HAVE_GMTIME_R
struct tm gmt;
#endif
struct tm *timeptr = NULL;
time_t tm = 0;
const char *newval;
long int rtime;
long int hours, minutes, seconds;
int negative = 0;
char * endptr;
if ( 0 == strcmpic(*header, "If-Modified-Since: Wed, 08 Jun 1955 12:00:00 GMT"))
{
/*
* The client got an error message because of a temporary problem,
* the problem is gone and the client now tries to revalidate our
* error message on the real server. The revalidation would always
* end with the transmission of the whole document and there is
* no need to expose the bogus If-Modified-Since header.
*/
log_error(LOG_LEVEL_HEADER, "Crunching useless If-Modified-Since header.");
freez(*header);
}
else if (csp->action->flags & ACTION_HIDE_IF_MODIFIED_SINCE)
{
newval = csp->action->string[ACTION_STRING_IF_MODIFIED_SINCE];
if ((0 == strcmpic(newval, "block")))
{
log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
freez(*header);
}
else /* add random value */
{
const char *header_time = *header + sizeof("If-Modified-Since:");
if (JB_ERR_OK != parse_header_time(header_time, &tm))
{
log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
freez(*header);
}
else
{
rtime = strtol(newval, &endptr, 0);
if (rtime)
{
log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %d minut%s)",
*header, rtime, (rtime == 1 || rtime == -1) ? "e": "es");
if (rtime < 0)
{
rtime *= -1;
negative = 1;
}
rtime *= 60;
rtime = pick_from_range(rtime);
}
else
{
log_error(LOG_LEVEL_ERROR, "Random range is 0. Assuming time transformation test.",
*header);
}
tm += rtime * (negative ? -1 : 1);
#ifdef HAVE_GMTIME_R
timeptr = gmtime_r(&tm, &gmt);
#elif FEATURE_PTHREAD
privoxy_mutex_lock(&gmtime_mutex);
timeptr = gmtime(&tm);
privoxy_mutex_unlock(&gmtime_mutex);
#else
timeptr = gmtime(&tm);
#endif
strftime(newheader, sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr);
freez(*header);
*header = strdup("If-Modified-Since: ");
string_append(header, newheader);
if (*header == NULL)
{
log_error(LOG_LEVEL_HEADER, "Insufficient memory, header crunched without replacement.");
return JB_ERR_MEMORY;
}
hours = rtime / 3600;
minutes = rtime / 60 % 60;
seconds = rtime % 60;
log_error(LOG_LEVEL_HEADER,
"Randomized: %s (%s %d hou%s %d minut%s %d second%s",
*header, (negative) ? "subtracted" : "added", hours,
(hours == 1) ? "r" : "rs", minutes, (minutes == 1) ? "e" : "es",
seconds, (seconds == 1) ? ")" : "s)");
}
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_if_none_match
*
* Description : Remove the If-None-Match header.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_if_none_match(struct client_state *csp, char **header)
{
if (csp->action->flags & ACTION_CRUNCH_IF_NONE_MATCH)
{
log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
freez(*header);
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_x_filter
*
* Description : Disables filtering if the client set "X-Filter: No".
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success
*
*********************************************************************/
jb_err client_x_filter(struct client_state *csp, char **header)
{
if ( 0 == strcmpic(*header, "X-Filter: No"))
{
if (!(csp->config->feature_flags & RUNTIME_FEATURE_HTTP_TOGGLE))
{
log_error(LOG_LEVEL_INFO, "Ignored the client's request to fetch without filtering.");
}
else
{
if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
{
log_error(LOG_LEVEL_HEADER,
"force-text-mode overruled the client's request to fetch without filtering!");
}
else
{
csp->content_type = CT_TABOO; /* XXX: This hack shouldn't be necessary */
csp->flags |= CSP_FLAG_NO_FILTERING;
log_error(LOG_LEVEL_HEADER, "Accepted the client's request to fetch without filtering.");
}
log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
freez(*header);
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_range
*
* Description : Removes Range, Request-Range and If-Range headers if
* content filtering is enabled. If the client's version
* of the document has been altered by Privoxy, the server
* could interpret the range differently than the client
* intended in which case the user could end up with
* corrupted content.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK
*
*********************************************************************/
static jb_err client_range(struct client_state *csp, char **header)
{
if (content_filters_enabled(csp->action))
{
log_error(LOG_LEVEL_HEADER, "Content filtering is enabled."
" Crunching: \'%s\' to prevent range-mismatch problems.", *header);
freez(*header);
}
return JB_ERR_OK;
}
/* the following functions add headers directly to the header list */
/*********************************************************************
*
* Function : client_host_adder
*
* Description : Adds the Host: header field if it is missing.
* Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_host_adder(struct client_state *csp)
{
char *p;
jb_err err;
if (csp->flags & CSP_FLAG_HOST_HEADER_IS_SET)
{
/* Header already set by the client, nothing to do. */
return JB_ERR_OK;
}
if ( !csp->http->hostport || !*(csp->http->hostport))
{
/* XXX: When does this happen and why is it OK? */
log_error(LOG_LEVEL_INFO, "Weirdness in client_host_adder detected and ignored.");
return JB_ERR_OK;
}
/*
* remove 'user:pass@' from 'proto://user:pass@host'
*/
if ( (p = strchr( csp->http->hostport, '@')) != NULL )
{
p++;
}
else
{
p = csp->http->hostport;
}
/* XXX: Just add it, we already made sure that it will be unique */
log_error(LOG_LEVEL_HEADER, "addh-unique: Host: %s", p);
err = enlist_unique_header(csp->headers, "Host", p);
return err;
}
#if 0
/*********************************************************************
*
* Function : client_accept_encoding_adder
*
* Description : Add an Accept-Encoding header to the client's request
* that disables compression if the action applies, and
* the header is not already there. Called from `sed'.
* Note: For HTTP/1.0, the absence of the header is enough.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_accept_encoding_adder(struct client_state *csp)
{
if ( ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
&& (!strcmpic(csp->http->ver, "HTTP/1.1")) )
{
return enlist_unique(csp->headers, "Accept-Encoding: identity;q=1.0, *;q=0", 16);
}
return JB_ERR_OK;
}
#endif
/*********************************************************************
*
* Function : client_xtra_adder
*
* Description : Used in the add_client_headers list. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_xtra_adder(struct client_state *csp)
{
struct list_entry *lst;
jb_err err;
for (lst = csp->action->multi[ACTION_MULTI_ADD_HEADER]->first;
lst ; lst = lst->next)
{
log_error(LOG_LEVEL_HEADER, "addh: %s", lst->str);
err = enlist(csp->headers, lst->str);
if (err)
{
return err;
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : client_x_forwarded_for_adder
*
* Description : Used in the add_client_headers list. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_x_forwarded_for_adder(struct client_state *csp)
{
char *header = NULL;
jb_err err;
if (!((csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR)
&& (0 == strcmpic(csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR], "add")))
|| (csp->flags & CSP_FLAG_X_FORWARDED_FOR_APPENDED))
{
/*
* If we aren't adding X-Forwarded-For headers,
* or we already appended an existing X-Forwarded-For
* header, there's nothing left to do here.
*/
return JB_ERR_OK;
}
header = strdup("X-Forwarded-For: ");
string_append(&header, csp->ip_addr_str);
if (header == NULL)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "addh: %s", header);
err = enlist(csp->headers, header);
freez(header);
return err;
}
/*********************************************************************
*
* Function : server_connection_close_adder
*
* Description : "Temporary" fix for the needed but missing HTTP/1.1
* support. Adds a "Connection: close" header to csp->headers
* unless the header was already present. Called from `sed'.
*
* FIXME: This whole function shouldn't be neccessary!
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_connection_close_adder(struct client_state *csp)
{
const unsigned int flags = csp->flags;
const char *response_status_line = csp->headers->first->str;
if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
&& (flags & CSP_FLAG_SERVER_CONNECTION_CLOSE_SET))
{
return JB_ERR_OK;
}
/*
* XXX: if we downgraded the response, this check will fail.
*/
if ((csp->config->feature_flags &
RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
&& (NULL != response_status_line)
&& !strncmpic(response_status_line, "HTTP/1.1", 8))
{
log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
"without Connection header implies keep-alive.");
csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
}
log_error(LOG_LEVEL_HEADER, "Adding: Connection: close");
return enlist(csp->headers, "Connection: close");
}
/*********************************************************************
*
* Function : client_connection_header_adder
*
* Description : Adds a proper "Connection:" header to csp->headers
* unless the header was already present. Called from `sed'.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err client_connection_header_adder(struct client_state *csp)
{
const unsigned int flags = csp->flags;
const char *wanted_header = get_appropiate_connection_header(csp);
if (!(flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
&& (flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET))
{
return JB_ERR_OK;
}
log_error(LOG_LEVEL_HEADER, "Adding: %s", wanted_header);
return enlist(csp->headers, wanted_header);
}
/*********************************************************************
*
* Function : server_http
*
* Description : - Save the HTTP Status into csp->http->status
* - Set CT_TABOO to prevent filtering if the answer
* is a partial range (HTTP status 206)
* - Rewrite HTTP/1.1 answers to HTTP/1.0 if +downgrade
* action applies.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_http(struct client_state *csp, char **header)
{
sscanf(*header, "HTTP/%*d.%*d %d", &(csp->http->status));
if (csp->http->status == 206)
{
csp->content_type = CT_TABOO;
}
if ((csp->action->flags & ACTION_DOWNGRADE) != 0)
{
/* XXX: Should we do a real validity check here? */
if (strlen(*header) > 8)
{
(*header)[7] = '0';
log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0");
}
else
{
/*
* XXX: Should we block the request or
* enlist a valid status code line here?
*/
log_error(LOG_LEVEL_INFO, "Malformed server response detected. "
"Downgrading to HTTP/1.0 impossible.");
}
}
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : server_set_cookie
*
* Description : Handle the server "cookie" header properly.
* Log cookie to the jar file. Then "crunch",
* accept or rewrite it to a session cookie.
* Called from `sed'.
*
* TODO: Allow the user to specify a new expiration
* time to cause the cookie to expire even before the
* browser is closed.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
* 2 : header = On input, pointer to header to modify.
* On output, pointer to the modified header, or NULL
* to remove the header. This function frees the
* original string if necessary.
*
* Returns : JB_ERR_OK on success, or
* JB_ERR_MEMORY on out-of-memory error.
*
*********************************************************************/
static jb_err server_set_cookie(struct client_state *csp, char **header)
{
time_t now;
time_t cookie_time;
time(&now);
if ((csp->action->flags & ACTION_NO_COOKIE_SET) != 0)
{
log_error(LOG_LEVEL_HEADER, "Crunching incoming cookie: %s", *header);
freez(*header);
}
else if ((csp->action->flags & ACTION_NO_COOKIE_KEEP) != 0)
{
/* Flag whether or not to log a message */
int changed = 0;
/* A variable to store the tag we're working on */
char *cur_tag;
/* Skip "Set-Cookie:" (11 characters) in header */
cur_tag = *header + 11;
/* skip whitespace between "Set-Cookie:" and value */
while (*cur_tag && ijb_isspace(*cur_tag))
{
cur_tag++;
}
/* Loop through each tag in the cookie */
while (*cur_tag)
{
/* Find next tag */
char *next_tag = strchr(cur_tag, ';');
if (next_tag != NULL)
{
/* Skip the ';' character itself */
next_tag++;
/* skip whitespace ";" and start of tag */
while (*next_tag && ijb_isspace(*next_tag))
{
next_tag++;
}
}
else
{
/* "Next tag" is the end of the string */
next_tag = cur_tag + strlen(cur_tag);
}
/*
* Check the expiration date to see
* if the cookie is still valid, if yes,
* rewrite it to a session cookie.
*/
if ((strncmpic(cur_tag, "expires=", 8) == 0) && *(cur_tag + 8))
{
char *expiration_date = cur_tag + 8; /* Skip "[Ee]xpires=" */
/* Did we detect the date properly? */
if (JB_ERR_OK != parse_header_time(expiration_date, &cookie_time))
{
/*
* Nope, treat it as if it was still valid.
*
* XXX: Should we remove the whole cookie instead?
*/
log_error(LOG_LEVEL_ERROR,
"Can't parse \'%s\', send by %s. Unsupported time format?", cur_tag, csp->http->url);
string_move(cur_tag, next_tag);
changed = 1;
}
else
{
/*
* Yes. Check if the cookie is still valid.
*
* If the cookie is already expired it's probably
* a delete cookie and even if it isn't, the browser
* will discard it anyway.
*/
/*
* XXX: timegm() isn't available on some AmigaOS
* versions and our replacement doesn't work.
*
* Our options are to either:
*
* - disable session-cookies-only completely if timegm
* is missing,
*
* - to simply remove all expired tags, like it has
* been done until Privoxy 3.0.6 and to live with
* the consequence that it can cause login/logout
* problems on servers that don't validate their
* input properly, or
*
* - to replace it with mktime in which
* case there is a slight chance of valid cookies
* passing as already expired.
*
* This is the way it's currently done and it's not
* as bad as it sounds. If the missing GMT offset is
* enough to change the result of the expiration check
* the cookie will be only valid for a few hours
* anyway, which in many cases will be shorter
* than a browser session.
*/
if (cookie_time - now < 0)
{
log_error(LOG_LEVEL_HEADER,
"Cookie \'%s\' is already expired and can pass unmodified.", *header);
/* Just in case some clown sets more then one expiration date */
cur_tag = next_tag;
}
else
{
/*
* Still valid, delete expiration date by copying
* the rest of the string over it.
*/
string_move(cur_tag, next_tag);
/* That changed the header, need to issue a log message */
changed = 1;
/*
* Note that the next tag has now been moved to *cur_tag,
* so we do not need to update the cur_tag pointer.
*/
}
}
}
else
{
/* Move on to next cookie tag */
cur_tag = next_tag;
}
}
if (changed)
{
assert(NULL != *header);
log_error(LOG_LEVEL_HEADER, "Cookie rewritten to a temporary one: %s",
*header);
}
}
return JB_ERR_OK;
}
#ifdef FEATURE_FORCE_LOAD
/*********************************************************************
*
* Function : strclean
*
* Description : In-Situ-Eliminate all occurances of substring in
* string
*
* Parameters :
* 1 : string = string to clean
* 2 : substring = substring to eliminate
*
* Returns : Number of eliminations
*
*********************************************************************/
int strclean(char *string, const char *substring)
{
int hits = 0;
size_t len;
char *pos, *p;
len = strlen(substring);
while((pos = strstr(string, substring)) != NULL)
{
p = pos + len;
do
{
*(p - len) = *p;
}
while (*p++ != '\0');
hits++;
}
return(hits);
}
#endif /* def FEATURE_FORCE_LOAD */
/*********************************************************************
*
* Function : parse_header_time
*
* Description : Parses time formats used in HTTP header strings
* to get the numerical respresentation.
*
* Parameters :
* 1 : header_time = HTTP header time as string.
* 2 : result = storage for header_time in seconds
*
* Returns : JB_ERR_OK if the time format was recognized, or
* JB_ERR_PARSE otherwise.
*
*********************************************************************/
static jb_err parse_header_time(const char *header_time, time_t *result)
{
struct tm gmt;
/*
* Zero out gmt to prevent time zone offsets.
*
* While this is only necessary on some platforms
* (mingw32 for example), I don't know how to
* detect these automatically and doing it everywhere
* shouldn't hurt.
*/
memset(&gmt, 0, sizeof(gmt));
/* Tue, 02 Jun 2037 20:00:00 */
if ((NULL == strptime(header_time, "%a, %d %b %Y %H:%M:%S", &gmt))
/* Tue, 02-Jun-2037 20:00:00 */
&& (NULL == strptime(header_time, "%a, %d-%b-%Y %H:%M:%S", &gmt))
/* Tue, 02-Jun-37 20:00:00 */
&& (NULL == strptime(header_time, "%a, %d-%b-%y %H:%M:%S", &gmt))
/* Tuesday, 02-Jun-2037 20:00:00 */
&& (NULL == strptime(header_time, "%A, %d-%b-%Y %H:%M:%S", &gmt))
/* Tuesday Jun 02 20:00:00 2037 */
&& (NULL == strptime(header_time, "%A %b %d %H:%M:%S %Y", &gmt)))
{
return JB_ERR_PARSE;
}
*result = timegm(&gmt);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : get_destination_from_headers
*
* Description : Parse the "Host:" header to get the request's destination.
* Only needed if the client's request was forcefully
* redirected into Privoxy.
*
* Code mainly copied from client_host() which is currently
* run too late for this purpose.
*
* Parameters :
* 1 : headers = List of headers (one of them hopefully being
* the "Host:" header)
* 2 : http = storage for the result (host, port and hostport).
*
* Returns : JB_ERR_MEMORY in case of memory problems,
* JB_ERR_PARSE if the host header couldn't be found,
* JB_ERR_OK otherwise.
*
*********************************************************************/
jb_err get_destination_from_headers(const struct list *headers, struct http_request *http)
{
char *q;
char *p;
char *host;
host = get_header_value(headers, "Host:");
if (NULL == host)
{
log_error(LOG_LEVEL_ERROR, "No \"Host:\" header found.");
return JB_ERR_PARSE;
}
if (NULL == (p = strdup((host))))
{
log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
return JB_ERR_MEMORY;
}
chomp(p);
if (NULL == (q = strdup(p)))
{
freez(p);
log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
return JB_ERR_MEMORY;
}
freez(http->hostport);
http->hostport = p;
freez(http->host);
http->host = q;
q = strchr(http->host, ':');
if (q != NULL)
{
/* Terminate hostname and evaluate port string */
*q++ = '\0';
http->port = atoi(q);
}
else
{
http->port = http->ssl ? 443 : 80;
}
/* Rebuild request URL */
freez(http->url);
http->url = strdup(http->ssl ? "https://" : "http://");
string_append(&http->url, http->hostport);
string_append(&http->url, http->path);
if (http->url == NULL)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "Destination extracted from \"Host:\" header. New request URL: %s",
http->url);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : create_forged_referrer
*
* Description : Helper for client_referrer to forge a referer as
* 'http://[hostname:port/' to fool stupid
* checks for in-site links
*
* Parameters :
* 1 : header = Pointer to header pointer
* 2 : hostport = Host and optionally port as string
*
* Returns : JB_ERR_OK in case of success, or
* JB_ERR_MEMORY in case of memory problems.
*
*********************************************************************/
static jb_err create_forged_referrer(char **header, const char *hostport)
{
assert(NULL == *header);
*header = strdup("Referer: http://");
string_append(header, hostport);
string_append(header, "/");
if (NULL == *header)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : create_fake_referrer
*
* Description : Helper for client_referrer to create a fake referrer
* based on a string supplied by the user.
*
* Parameters :
* 1 : header = Pointer to header pointer
* 2 : hosthost = Referrer to fake
*
* Returns : JB_ERR_OK in case of success, or
* JB_ERR_MEMORY in case of memory problems.
*
*********************************************************************/
static jb_err create_fake_referrer(char **header, const char *fake_referrer)
{
assert(NULL == *header);
if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
{
log_error(LOG_LEVEL_HEADER,
"Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
}
*header = strdup("Referer: ");
string_append(header, fake_referrer);
if (NULL == *header)
{
return JB_ERR_MEMORY;
}
log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : handle_conditional_hide_referrer_parameter
*
* Description : Helper for client_referrer to crunch or forge
* the referrer header if the host has changed.
*
* Parameters :
* 1 : header = Pointer to header pointer
* 2 : host = The target host (may include the port)
* 3 : parameter_conditional_block = Boolean to signal
* if we're in conditional-block mode. If not set,
* we're in conditional-forge mode.
*
* Returns : JB_ERR_OK in case of success, or
* JB_ERR_MEMORY in case of memory problems.
*
*********************************************************************/
static jb_err handle_conditional_hide_referrer_parameter(char **header,
const char *host, const int parameter_conditional_block)
{
char *referer = strdup(*header);
const size_t hostlenght = strlen(host);
const char *referer_url = NULL;
if (NULL == referer)
{
freez(*header);
return JB_ERR_MEMORY;
}
/* referer begins with 'Referer: http[s]://' */
if ((hostlenght+17) < strlen(referer))
{
/*
* Shorten referer to make sure the referer is blocked
* if www.example.org/www.example.com-shall-see-the-referer/
* links to www.example.com/
*/
referer[hostlenght+17] = '\0';
}
referer_url = strstr(referer, "http://");
if ((NULL == referer_url) || (NULL == strstr(referer_url, host)))
{
/* Host has changed, Referer is invalid or a https URL. */
if (parameter_conditional_block)
{
log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
freez(*header);
}
else
{
freez(*header);
freez(referer);
return create_forged_referrer(header, host);
}
}
freez(referer);
return JB_ERR_OK;
}
/*********************************************************************
*
* Function : get_appropiate_connection_header
*
* Description : Returns an appropiate Connection header
* depending on whether or not we try to keep
* the connection to the server alive.
*
* Parameters :
* 1 : csp = Current client state (buffers, headers, etc...)
*
* Returns : Pointer to statically allocated header buffer.
*
*********************************************************************/
static const char *get_appropiate_connection_header(const struct client_state *csp)
{
static const char connection_keep_alive[] = "Connection: keep-alive";
static const char connection_close[] = "Connection: close";
if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
&& (csp->http->ssl == 0))
{
return connection_keep_alive;
}
return connection_close;
}
/*
Local Variables:
tab-width: 3
end:
*/