X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=parsers.c;h=88530a855c6786e9b6912d7f8c73697558fb6499;hp=df2ae59a437fe209a9b0c867516a61b8a061625f;hb=cd275efe90ca39d461537daf389e79a3cd79e507;hpb=46975ba74bf01a8d34c738f00fb4ff4537b90817 diff --git a/parsers.c b/parsers.c index df2ae59a..88530a85 100644 --- a/parsers.c +++ b/parsers.c @@ -1,4 +1,4 @@ -const char parsers_rcs[] = "$Id: parsers.c,v 1.55 2002/05/08 16:01:07 oes Exp $"; +const char parsers_rcs[] = "$Id: parsers.c,v 1.147 2008/11/04 17:20:31 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/parsers.c,v $ @@ -10,10 +10,14 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.55 2002/05/08 16:01:07 oes Exp $" * `client_uagent', `client_x_forwarded', * `client_x_forwarded_adder', `client_xtra_adder', * `content_type', `crumble', `destroy_list', `enlist', - * `flush_socket', ``get_header', `sed', - * and `server_set_cookie'. - * - * Copyright : Written by and Copyright (C) 2001 the SourceForge + * `flush_socket', ``get_header', `sed', `filter_header' + * `server_content_encoding', `server_content_disposition', + * `server_last_modified', `client_accept_language', + * `crunch_client_header', `client_if_modified_since', + * `client_if_none_match', `get_destination_from_headers', + * `parse_header_time', `decompress_iob' and `server_set_cookie'. + * + * Copyright : Written by and Copyright (C) 2001-2008 the SourceForge * Privoxy team. http://www.privoxy.org/ * * Based on the Internet Junkbuster originally written @@ -40,6 +44,475 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.55 2002/05/08 16:01:07 oes Exp $" * * Revisions : * $Log: parsers.c,v $ + * 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 . 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() @@ -395,25 +868,47 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.55 2002/05/08 16:01:07 oes Exp $" #include #include +#ifdef __GLIBC__ +/* + * Convince GNU's libc to provide a strptime prototype. + */ +#define __USE_XOPEN +#endif /*__GLIBC__ */ +#include + +#ifdef FEATURE_ZLIB +#include +#endif + #if !defined(_WIN32) && !defined(__OS2__) #include #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 "encode.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 it's argument directly + * 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". @@ -424,56 +919,132 @@ const char parsers_h_rcs[] = PARSERS_H_VERSION; #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; +}; -const struct parsers client_patterns[] = { - { "referer:", 8, client_referrer }, +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 }, + { "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, crumble }, -/* { "if-modified-since:", 18, crumble }, */ + { "TE:", 3, client_te }, + { "Host:", 5, client_host }, + { "if-modified-since:", 18, client_if_modified_since }, { "Keep-Alive:", 11, crumble }, - { "connection:", 11, crumble }, + { "connection:", 11, client_connection }, { "proxy-connection:", 17, crumble }, - { NULL, 0, NULL } + { "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 } }; - -const struct parsers server_patterns[] = { - { "HTTP", 4, server_http }, - { "set-cookie:", 11, server_set_cookie }, - { "connection:", 11, crumble }, - { "Content-Type:", 13, server_content_type }, - { "Content-Length:", 15, server_content_length }, - { "Content-MD5:", 12, server_content_md5 }, - { "Content-Encoding:", 17, server_content_encoding }, - { "Transfer-Encoding:", 18, server_transfer_coding }, - { "Keep-Alive:", 11, crumble }, - { 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 } }; - -const add_header_func_ptr add_client_headers[] = { +static const add_header_func_ptr add_client_headers[] = { client_host_adder, - client_cookie_adder, - client_x_forwarded_adder, + client_x_forwarded_for_adder, client_xtra_adder, - client_accept_encoding_adder, - connection_close_adder, + /* Temporarily disabled: client_accept_encoding_adder, */ + client_connection_header_adder, NULL }; - -const add_header_func_ptr add_server_headers[] = { - connection_close_adder, +static const add_header_func_ptr add_server_headers[] = { + server_connection_close_adder, NULL }; - /********************************************************************* * * Function : flush_socket @@ -482,7 +1053,7 @@ const add_header_func_ptr add_server_headers[] = { * * Parameters : * 1 : fd = file descriptor of the socket to read - * 2 : csp = Current client state (buffers, headers, etc...) + * 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, @@ -492,9 +1063,8 @@ const add_header_func_ptr add_server_headers[] = { * file, the results are not portable. * *********************************************************************/ -int flush_socket(jb_socket fd, struct client_state *csp) +int flush_socket(jb_socket fd, struct iob *iob) { - struct iob *iob = csp->iob; int len = iob->eod - iob->cur; if (len <= 0) @@ -536,9 +1106,9 @@ jb_err add_to_iob(struct client_state *csp, char *buf, int n) if (n <= 0) return JB_ERR_OK; - used = iob->eod - iob->buf; - offset = iob->cur - iob->buf; - need = used + n + 1; + 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. @@ -546,7 +1116,9 @@ jb_err add_to_iob(struct client_state *csp, char *buf, int n) */ if (need > csp->config->buffer_limit) { - log_error(LOG_LEVEL_ERROR, "Buffer limit reached while extending the buffer (iob)"); + 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; } @@ -588,234 +1160,1439 @@ jb_err add_to_iob(struct client_state *csp, char *buf, int n) } +#ifdef FEATURE_ZLIB /********************************************************************* * - * Function : get_header + * Function : decompress_iob * - * Description : This (odd) routine will parse the csp->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 : 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. + * Returns : JB_ERR_OK on success, + * JB_ERR_MEMORY if out-of-memory limit reached, and + * JB_ERR_COMPRESS if error decompressing buffer. * *********************************************************************/ -char *get_header(struct client_state *csp) +jb_err decompress_iob(struct client_state *csp) { - struct iob *iob; - char *p, *q, *ret; - iob = csp->iob; - - if ((iob->cur == NULL) - || ((p = strchr(iob->cur, '\n')) == NULL)) + 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 < 10) { - return(""); /* couldn't find a complete header */ + /* + * 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; } - *p = '\0'; - - ret = strdup(iob->cur); - if (ret == NULL) + if (csp->content_type & CT_GZIP) { - /* FIXME No way to handle error properly */ - log_error(LOG_LEVEL_FATAL, "Out of memory in get_header()"); - } + /* + * 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. + */ - iob->cur = p+1; + /* + * 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; - if ((q = strchr(ret, '\r')) != NULL) *q = '\0'; + /* 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; - /* is this a blank line (i.e. the end of the header) ? */ - if (*ret == '\0') - { - freez(ret); - return(NULL); - } + assert(skip_bytes == *csp->iob->cur - 2 + ((*csp->iob->cur - 1) << 8)); - return(ret); + /* + * 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)); + } -/********************************************************************* - * - * 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; + /* Skip the comment if necessary. */ + if (flags & 0x10) + { + /* A null-terminated string is supposed to follow. */ + while (*cur++ && (cur < csp->iob->eod)); + } - assert(header_list); - assert(header_name); - length = strlen(header_name); + /* Skip the CRC if necessary. */ + if (flags & 0x02) + { + cur += 2; + } - 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)) + if (cur >= csp->iob->eod) { /* - * Found: return pointer to start of value + * If the current position pointer reached or passed + * the buffer end, we were obviously tricked to skip + * too much. */ - ret = (char *) (cur_entry->str + length); - while (*ret && ijb_isspace(*ret)) ret++; - return(ret); + 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; + } - /* - * Not found + /* 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. */ - return NULL; + 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; + } -/********************************************************************* - * - * 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 : pats = list of patterns to match against headers - * 2 : more_headers = list of functions to add more - * headers (client or server) - * 3 : csp = Current client state (buffers, headers, etc...) - * - * Returns : Single pointer to a fully formed header, or NULL - * on out-of-memory error. - * - *********************************************************************/ -char *sed(const struct parsers pats[], - const add_header_func_ptr more_headers[], - struct client_state *csp) -{ - struct list_entry *p; - const struct parsers *v; - const add_header_func_ptr *f; - jb_err err = JB_ERR_OK; + assert(bufsize >= skip_size); + memcpy(buf, csp->iob->buf, skip_size); + zstr.avail_out = bufsize - skip_size; + zstr.next_out = (Bytef *)buf + skip_size; - for (v = pats; (err == JB_ERR_OK) && (v->str != NULL) ; v++) + /* Try to decompress the whole stream in one shot. */ + while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH))) { - for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL) ; p = p->next) + /* 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) { - /* Header crunch()ed in previous run? -> ignore */ - if (p->str == NULL) continue; + 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; + } - if (v == pats) log_error(LOG_LEVEL_HEADER, "scan: %s", p->str); + /* Try doubling the buffer size each time. */ + bufsize *= 2; - if (strncmpic(p->str, v->str, v->len) == 0) - { - err = v->parser(csp, (char **)&(p->str)); - } + /* 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 > 0); + + buf = tmpbuf; } } - /* place any additional headers on the csp->headers list */ - for (f = more_headers; (err == JB_ERR_OK) && (*f) ; f++) + if (Z_STREAM_ERROR == inflateEnd(&zstr)) { - err = (*f)(csp); + 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 (err != JB_ERR_OK) + if (status != Z_STREAM_END) { - return NULL; + /* 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; } - return list_to_text(csp->headers); -} + /* + * 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 > 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; -/* here begins the family of parser functions that reformat header lines */ +} +#endif /* defined(FEATURE_ZLIB) */ /********************************************************************* * - * Function : crumble + * Function : string_move * - * Description : This is called if a header matches a pattern to "crunch" + * 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 : 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. + * 1 : dst = Destination to overwrite + * 2 : src = Source to move. * - * Returns : JB_ERR_OK on success, or - * JB_ERR_MEMORY on out-of-memory error. + * Returns : N/A * *********************************************************************/ -jb_err crumble(struct client_state *csp, char **header) +static void string_move(char *dst, char *src) { - log_error(LOG_LEVEL_HEADER, "crunch!"); - freez(*header); - return JB_ERR_OK; + assert(dst < src); + + /* +1 to copy the terminating nul as well. */ + memmove(dst, src, strlen(src)+1); } /********************************************************************* * - * Function : server_content_type + * Function : normalize_lws * - * Description : Set the content-type for filterable types (text/.*, - * javascript and image/gif) unless filtering has been - * forbidden (CT_TABOO) while parsing earlier headers. + * 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 : 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. + * 1 : header = A header with linear white space to reduce. * - * Returns : JB_ERR_OK on success, or - * JB_ERR_MEMORY on out-of-memory error. + * Returns : N/A * *********************************************************************/ -jb_err server_content_type(struct client_state *csp, char **header) +static void normalize_lws(char *header) { - if (csp->content_type != CT_TABOO) - { - if (strstr(*header, " text/") - || strstr(*header, "application/x-javascript")) - csp->content_type = CT_TEXT; - else if (strstr(*header, " image/gif")) - csp->content_type = CT_GIF; - else - csp->content_type = 0; - } + char *p = header; - return JB_ERR_OK; -} + 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()"); + } + + 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. */ + 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) +{ + 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; +} /********************************************************************* @@ -824,8 +2601,8 @@ jb_err server_content_type(struct client_state *csp, char **header) * * Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses * - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked" - * - Change from "chunked" to "identity" if body was chunked - * but has been de-chunked for filtering. + * - Remove header if body was chunked but has been + * de-chunked for filtering. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -838,13 +2615,20 @@ jb_err server_content_type(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_transfer_coding(struct client_state *csp, char **header) +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; } @@ -856,14 +2640,16 @@ jb_err server_transfer_coding(struct client_state *csp, char **header) csp->flags |= CSP_FLAG_CHUNKED; /* - * If the body was modified, it has been - * de-chunked first, so adjust the header: + * 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); - *header = strdup("Transfer-Encoding: identity"); - return (header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; } } @@ -875,7 +2661,16 @@ jb_err server_transfer_coding(struct client_state *csp, char **header) * * Function : server_content_encoding * - * Description : Prohibit filtering (CT_TABOO) if content encoding compresses + * 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...) @@ -888,15 +2683,62 @@ jb_err server_transfer_coding(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_content_encoding(struct client_state *csp, char **header) +static jb_err server_content_encoding(struct client_state *csp, char **header) { - /* - * Turn off pcrs and gif filtering if body compressed - */ +#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")) { - csp->content_type = CT_TABOO; + /* + * 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; @@ -905,7 +2747,7 @@ jb_err server_content_encoding(struct client_state *csp, char **header) /********************************************************************* * - * Function : server_content_length + * Function : server_adjust_content_length * * Description : Adjust Content-Length header if we modified * the body. @@ -921,24 +2763,68 @@ jb_err server_content_encoding(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_content_length(struct client_state *csp, char **header) +static jb_err server_adjust_content_length(struct client_state *csp, char **header) { - if (csp->content_length != 0) /* Content length has been modified */ + 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(100); + *header = (char *) zalloc(max_header_length); if (*header == NULL) { return JB_ERR_MEMORY; } - sprintf(*header, "Content-Length: %d", (int) csp->content_length); + 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 int content_length = 0; + + assert(*(*header+14) == ':'); - log_error(LOG_LEVEL_HEADER, "Adjust Content-Length to %d", (int) csp->content_length); + if (1 != sscanf(*header+14, ": %u", &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 */ /********************************************************************* @@ -959,7 +2845,7 @@ jb_err server_content_length(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_content_md5(struct client_state *csp, char **header) +static jb_err server_content_md5(struct client_state *csp, char **header) { if (csp->flags & CSP_FLAG_MODIFIED) { @@ -971,6 +2857,216 @@ jb_err server_content_md5(struct client_state *csp, char **header) } +/********************************************************************* + * + * 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 @@ -990,21 +3086,27 @@ jb_err server_content_md5(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_accept_encoding(struct client_state *csp, char **header) +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, "Supressed offer to compress content"); + log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content"); freez(*header); - 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; - } - } + + /* 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; @@ -1029,22 +3131,102 @@ jb_err client_accept_encoding(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_te(struct client_state *csp, char **header) +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, "Supressed offer to compress transfer"); + 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_referrer + * Function : client_accept_language * - * Description : Handle the "referer" config setting properly. + * Description : Handle the "Accept-Language" config setting properly. * Called from `sed'. * * Parameters : @@ -1058,71 +3240,88 @@ jb_err client_te(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_referrer(struct client_state *csp, char **header) +static jb_err client_accept_language(struct client_state *csp, char **header) { const char *newval; -#ifdef FEATURE_FORCE_LOAD - /* Since the referrer can include the prefix even - * even if the request itself is non-forced, we must - * clean it unconditionally - */ - strclean(*header, FORCE_PREFIX); -#endif /* def FEATURE_FORCE_LOAD */ - /* - * Are we sending referer? + * Are we messing with the Accept-Language? */ - if ((csp->action->flags & ACTION_HIDE_REFERER) == 0) + if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0) { + /*I don't think so*/ return JB_ERR_OK; } - freez(*header); - - newval = csp->action->string[ACTION_STRING_REFERER]; + newval = csp->action->string[ACTION_STRING_LANGUAGE]; if ((newval == NULL) || (0 == strcmpic(newval, "block")) ) { /* - * Blocking referer + * Blocking Accept-Language header */ - log_error(LOG_LEVEL_HEADER, "crunch!"); + log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!"); + freez(*header); return JB_ERR_OK; } - else if (0 == strncmpic(newval, "http://", 7)) - { + else + { /* - * We have a specific (fixed) referer we want to send. + * Replacing Accept-Language header */ - log_error(LOG_LEVEL_HEADER, "modified"); - - *header = strdup("Referer: "); - string_append(header, newval); + freez(*header); + *header = strdup("Accept-Language: "); + string_append(header, newval); - return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; + 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); + } } - else + 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)) { - /* - * Forge a referer as http://[hostname:port of REQUEST]/ - * to fool stupid checks for in-site links - */ - if (0 != strcmpic(newval, "forge")) + crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER]; + + /* Is the current header the lucky one? */ + if (strstr(*header, crunch_pattern)) { - /* - * Invalid choice - but forge is probably the best default. - */ - log_error(LOG_LEVEL_ERROR, "Bad parameter: +referer{%s}", newval); + log_error(LOG_LEVEL_HEADER, "Crunching client header: %s (contains: %s)", *header, crunch_pattern); + freez(*header); } - - *header = strdup("Referer: http://"); - string_append(header, csp->http->hostport); - string_append(header, "/"); - log_error(LOG_LEVEL_HEADER, "crunch+forge to %s", *header); - - return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; } + return JB_ERR_OK; } @@ -1145,7 +3344,7 @@ jb_err client_referrer(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_uagent(struct client_state *csp, char **header) +static jb_err client_uagent(struct client_state *csp, char **header) { const char *newval; @@ -1160,12 +3359,12 @@ jb_err client_uagent(struct client_state *csp, char **header) return JB_ERR_OK; } - log_error(LOG_LEVEL_HEADER, "modified"); - 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; } @@ -1187,11 +3386,11 @@ jb_err client_uagent(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_ua(struct client_state *csp, char **header) +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, "crunch!"); + log_error(LOG_LEVEL_HEADER, "crunched User-Agent!"); freez(*header); } @@ -1217,7 +3416,7 @@ jb_err client_ua(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_from(struct client_state *csp, char **header) +static jb_err client_from(struct client_state *csp, char **header) { const char *newval; @@ -1235,7 +3434,7 @@ jb_err client_from(struct client_state *csp, char **header) */ if ((newval == NULL) || (0 == strcmpic(newval, "block")) ) { - log_error(LOG_LEVEL_HEADER, "crunch!"); + log_error(LOG_LEVEL_HEADER, "crunched From!"); return JB_ERR_OK; } @@ -1252,9 +3451,10 @@ jb_err client_from(struct client_state *csp, char **header) * * Function : client_send_cookie * - * Description : Handle the "cookie" header properly. Called from `sed'. - * If cookie is accepted, add it to the cookie_list, - * else we crunch it. Mmmmmmmmmmm ... 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...) @@ -1267,27 +3467,15 @@ jb_err client_from(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_send_cookie(struct client_state *csp, char **header) +static jb_err client_send_cookie(struct client_state *csp, char **header) { - jb_err result = JB_ERR_OK; - - if ((csp->action->flags & ACTION_NO_COOKIE_READ) == 0) + if (csp->action->flags & ACTION_NO_COOKIE_READ) { - /* strlen("cookie: ") == 8 */ - result = enlist(csp->cookie_list, *header + 8); - } - else - { - log_error(LOG_LEVEL_HEADER, " crunch!"); + log_error(LOG_LEVEL_HEADER, "Crunched outgoing cookie: %s", *header); + freez(*header); } - /* - * Always remove the cookie here. The cookie header - * will be sent at the end of the header. - */ - freez(*header); - - return result; + return JB_ERR_OK; } @@ -1311,86 +3499,406 @@ jb_err client_send_cookie(struct client_state *csp, char **header) *********************************************************************/ jb_err client_x_forwarded(struct client_state *csp, char **header) { - if ((csp->action->flags & ACTION_HIDE_FORWARDED) == 0) + if (0 != (csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR)) { - /* Save it so we can re-add it later */ - freez(csp->x_forwarded); - csp->x_forwarded = *header; + const char *parameter = csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR]; - /* - * Always set *header = NULL, since this information - * will be sent at the end of the header. - */ - *header = NULL; + 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); + } } - else + + 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"))) { - freez(*header); - log_error(LOG_LEVEL_HEADER, " crunch!"); + assert(*(*header+12) == ':'); + if (1 == sscanf(*header+12, ": %u", &max_forwards)) + { + if (max_forwards > 0) + { + snprintf(*header, strlen(*header)+1, "Max-Forwards: %u", --max_forwards); + log_error(LOG_LEVEL_HEADER, "Max-Forwards value for %s request reduced to %u.", + 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; } -/* the following functions add headers directly to the header list */ /********************************************************************* * - * Function : client_host_adder + * Function : client_host * - * Description : (re)adds the host header. Called from `sed'. + * 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. * *********************************************************************/ -jb_err client_host_adder(struct client_state *csp) +static jb_err client_host(struct client_state *csp, char **header) { - char *p; - char *pos; - jb_err err; + char *p, *q; - if ( !csp->http->hostport || !*(csp->http->hostport)) + /* + * 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; } - p = strdup("Host: "); - /* - ** remove 'user:pass@' from 'proto://user:pass@host' - */ - if ( (pos = strchr( csp->http->hostport, '@')) != NULL ) + if (!csp->http->hostport || (*csp->http->hostport == '*') || + *csp->http->hostport == ' ' || *csp->http->hostport == '\0') { - string_append(&p, pos+1); + + 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); } - else + + /* 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")) { - string_append(&p, csp->http->hostport); + 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; +} + - if (p == NULL) +/********************************************************************* + * + * 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)) { - return JB_ERR_MEMORY; + log_error(LOG_LEVEL_HEADER, "Content filtering is enabled." + " Crunching: \'%s\' to prevent range-mismatch problems.", *header); + freez(*header); } - log_error(LOG_LEVEL_HEADER, "addh: %s", p); - - err = enlist(csp->headers, p); - - freez(p); - - return err; + return JB_ERR_OK; } +/* the following functions add headers directly to the header list */ /********************************************************************* * - * Function : client_cookie_adder + * Function : client_host_adder * - * Description : Used in the add_client_headers list. Called from `sed'. + * Description : Adds the Host: header field if it is missing. + * Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -1399,61 +3907,45 @@ jb_err client_host_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_cookie_adder(struct client_state *csp) +static jb_err client_host_adder(struct client_state *csp) { - struct list_entry *lst; - char *tmp; - struct list_entry *list1 = csp->cookie_list->first; - struct list_entry *list2 = csp->action->multi[ACTION_MULTI_WAFER]->first; - int first_cookie = 1; + char *p; jb_err err; - if ((list1 == NULL) && (list2 == NULL)) + if (csp->flags & CSP_FLAG_HOST_HEADER_IS_SET) { - /* Nothing to do */ + /* Header already set by the client, nothing to do. */ return JB_ERR_OK; } - tmp = strdup("Cookie: "); - - for (lst = list1; lst ; lst = lst->next) + if ( !csp->http->hostport || !*(csp->http->hostport)) { - if (first_cookie) - { - first_cookie = 0; - } - else - { - string_append(&tmp, "; "); - } - string_append(&tmp, lst->str); + /* 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; } - for (lst = list2; lst ; lst = lst->next) + /* + * remove 'user:pass@' from 'proto://user:pass@host' + */ + if ( (p = strchr( csp->http->hostport, '@')) != NULL ) { - if (first_cookie) - { - first_cookie = 0; - } - else - { - string_append(&tmp, "; "); - } - string_join(&tmp, cookie_encode(lst->str)); + p++; } - - if (tmp == NULL) + else { - return JB_ERR_MEMORY; + p = csp->http->hostport; } - log_error(LOG_LEVEL_HEADER, "addh: %s", tmp); - err = enlist(csp->headers, tmp); - free(tmp); + /* 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 @@ -1470,7 +3962,7 @@ jb_err client_cookie_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_accept_encoding_adder(struct client_state *csp) +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")) ) @@ -1480,6 +3972,7 @@ jb_err client_accept_encoding_adder(struct client_state *csp) return JB_ERR_OK; } +#endif /********************************************************************* @@ -1495,7 +3988,7 @@ jb_err client_accept_encoding_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_xtra_adder(struct client_state *csp) +static jb_err client_xtra_adder(struct client_state *csp) { struct list_entry *lst; jb_err err; @@ -1518,7 +4011,7 @@ jb_err client_xtra_adder(struct client_state *csp) /********************************************************************* * - * Function : client_x_forwarded_adder + * Function : client_x_forwarded_for_adder * * Description : Used in the add_client_headers list. Called from `sed'. * @@ -1529,35 +4022,34 @@ jb_err client_xtra_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err client_x_forwarded_adder(struct client_state *csp) +static jb_err client_x_forwarded_for_adder(struct client_state *csp) { - char *p = NULL; + char *header = NULL; jb_err err; - if ((csp->action->flags & ACTION_HIDE_FORWARDED) != 0) + 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; } - if (csp->x_forwarded) - { - p = strdup(csp->x_forwarded); - string_append(&p, ", "); - } - else - { - p = strdup("X-Forwarded-For: "); - } - string_append(&p, csp->ip_addr_str); + header = strdup("X-Forwarded-For: "); + string_append(&header, csp->ip_addr_str); - if (p == NULL) + if (header == NULL) { return JB_ERR_MEMORY; } - log_error(LOG_LEVEL_HEADER, "addh: %s", p); - err = enlist(csp->headers, p); - free(p); + log_error(LOG_LEVEL_HEADER, "addh: %s", header); + err = enlist(csp->headers, header); + freez(header); return err; } @@ -1565,11 +4057,12 @@ jb_err client_x_forwarded_adder(struct client_state *csp) /********************************************************************* * - * Function : connection_close_adder + * 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'. * - * Description : Adds a "Connection: close" header to csp->headers - * as a temporary fix for the needed but missing HTTP/1.1 - * support. Called from `sed'. * FIXME: This whole function shouldn't be neccessary! * * Parameters : @@ -1579,12 +4072,67 @@ jb_err client_x_forwarded_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err connection_close_adder(struct client_state *csp) +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 @@ -1606,7 +4154,7 @@ jb_err connection_close_adder(struct client_state *csp) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_http(struct client_state *csp, char **header) +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) @@ -1616,8 +4164,21 @@ jb_err server_http(struct client_state *csp, char **header) if ((csp->action->flags & ACTION_DOWNGRADE) != 0) { - (*header)[7] = '0'; - log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0"); + /* 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; @@ -1629,8 +4190,13 @@ jb_err server_http(struct client_state *csp, char **header) * Function : server_set_cookie * * Description : Handle the server "cookie" header properly. - * Log cookie to the jar file. Then "crunch" it, - * or accept it. Called from `sed'. + * 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...) @@ -1643,36 +4209,17 @@ jb_err server_http(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_set_cookie(struct client_state *csp, char **header) +static jb_err server_set_cookie(struct client_state *csp, char **header) { -#ifdef FEATURE_COOKIE_JAR - if (csp->config->jar) - { - /* - * Write timestamp into outbuf. - * - * Complex because not all OSs have tm_gmtoff or - * the %z field in strftime() - */ - char tempbuf[ BUFFER_SIZE ]; - time_t now; - struct tm tm_now; - time (&now); -#ifdef HAVE_LOCALTIME_R - tm_now = *localtime_r(&now, &tm_now); -#else - tm_now = *localtime (&now); -#endif - strftime(tempbuf, BUFFER_SIZE-6, "%b %d %H:%M:%S ", &tm_now); + time_t now; + time_t cookie_time; - /* strlen("set-cookie: ") = 12 */ - fprintf(csp->config->jar, "%s %s\t%s\n", tempbuf, csp->http->host, *header + 12); - } -#endif /* def FEATURE_COOKIE_JAR */ + time(&now); if ((csp->action->flags & ACTION_NO_COOKIE_SET) != 0) { - return crumble(csp, header); + log_error(LOG_LEVEL_HEADER, "Crunching incoming cookie: %s", *header); + freez(*header); } else if ((csp->action->flags & ACTION_NO_COOKIE_KEEP) != 0) { @@ -1713,22 +4260,89 @@ jb_err server_set_cookie(struct client_state *csp, char **header) next_tag = cur_tag + strlen(cur_tag); } - /* Is this the "Expires" tag? */ - if (strncmpic(cur_tag, "expires=", 8) == 0) + /* + * 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)) { - /* Delete the tag by copying the rest of the string over it. - * (Note that we cannot just use "strcpy(cur_tag, next_tag)", - * since the behaviour of strcpy is undefined for overlapping - * strings.) - */ - memmove(cur_tag, next_tag, strlen(next_tag) + 1); + char *expiration_date = cur_tag + 8; /* Skip "[Ee]xpires=" */ - /* That changed the header, need to issue a log message */ - changed = 1; + /* 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. + */ + } + } - /* Note that the next tag has now been moved to *cur_tag, - * so we do not need to update the cur_tag pointer. - */ } else { @@ -1739,7 +4353,9 @@ jb_err server_set_cookie(struct client_state *csp, char **header) if (changed) { - log_error(LOG_LEVEL_HEADER, "Changed cookie to a temporary one."); + assert(NULL != *header); + log_error(LOG_LEVEL_HEADER, "Cookie rewritten to a temporary one: %s", + *header); } } @@ -1762,11 +4378,14 @@ jb_err server_set_cookie(struct client_state *csp, char **header) * Returns : Number of eliminations * *********************************************************************/ -int strclean(const char *string, const char *substring) +int strclean(char *string, const char *substring) { - int hits = 0, len = strlen(substring); + int hits = 0; + size_t len; char *pos, *p; + len = strlen(substring); + while((pos = strstr(string, substring)) != NULL) { p = pos + len; @@ -1784,6 +4403,300 @@ int strclean(const char *string, const char *substring) #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); + + if (NULL == referer) + { + freez(*header); + return JB_ERR_MEMORY; + } + + /* referer begins with 'Referer: http[s]://' */ + if (hostlenght < (strlen(referer)-17)) + { + /* + * 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'; + } + if (NULL == strstr(referer, host)) + { + /* Host has changed */ + 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)) + { + return connection_keep_alive; + } + return connection_close; +} /* Local Variables: tab-width: 3