X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=parsers.c;h=2d3533dad821c0a0b482f06ed2c63be842e1ab5b;hp=bec42ec2c89792574aad29a9e24798b14f2d1221;hb=bb34ecc1ce527b800c3defd49cf3b49d1fe69580;hpb=17ef7337d1a41e4733c1ec662c3b1191d0c76a8a diff --git a/parsers.c b/parsers.c index bec42ec2..2d3533da 100644 --- a/parsers.c +++ b/parsers.c @@ -1,4 +1,4 @@ -const char parsers_rcs[] = "$Id: parsers.c,v 1.50 2002/03/12 01:45:35 oes Exp $"; +const char parsers_rcs[] = "$Id: parsers.c,v 1.220 2011/03/27 14:01:18 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/parsers.c,v $ @@ -10,11 +10,15 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.50 2002/03/12 01:45:35 oes Exp $" * `client_uagent', `client_x_forwarded', * `client_x_forwarded_adder', `client_xtra_adder', * `content_type', `crumble', `destroy_list', `enlist', - * `flush_socket', ``get_header', `sed', - * and `server_set_cookie'. + * `flush_socket', ``get_header', `sed', `filter_header' + * `server_content_encoding', `server_content_disposition', + * `server_last_modified', `client_accept_language', + * `crunch_client_header', `client_if_modified_since', + * `client_if_none_match', `get_destination_from_headers', + * `parse_header_time', `decompress_iob' and `server_set_cookie'. * - * Copyright : Written by and Copyright (C) 2001 the SourceForge - * IJBSWA team. http://ijbswa.sourceforge.net + * Copyright : Written by and Copyright (C) 2001-2009 the + * Privoxy team. http://www.privoxy.org/ * * Based on the Internet Junkbuster originally written * by and Copyright (C) 1997 Anonymous Coders and @@ -38,330 +42,8 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.50 2002/03/12 01:45:35 oes Exp $" * or write to the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston, MA 02111-1307, USA. * - * Revisions : - * $Log: parsers.c,v $ - * Revision 1.50 2002/03/12 01:45:35 oes - * More verbose logging - * - * Revision 1.49 2002/03/09 20:03:52 jongfoster - * - Making various functions return int rather than size_t. - * (Undoing a recent change). Since size_t is unsigned on - * Windows, functions like read_socket that return -1 on - * error cannot return a size_t. - * - * THIS WAS A MAJOR BUG - it caused frequent, unpredictable - * crashes, and also frequently caused JB to jump to 100% - * CPU and stay there. (Because it thought it had just - * read ((unsigned)-1) == 4Gb of data...) - * - * - The signature of write_socket has changed, it now simply - * returns success=0/failure=nonzero. - * - * - Trying to get rid of a few warnings --with-debug on - * Windows, I've introduced a new type "jb_socket". This is - * used for the socket file descriptors. On Windows, this - * is SOCKET (a typedef for unsigned). Everywhere else, it's - * an int. The error value can't be -1 any more, so it's - * now JB_INVALID_SOCKET (which is -1 on UNIX, and in - * Windows it maps to the #define INVALID_SOCKET.) - * - * - The signature of bind_port has changed. - * - * Revision 1.48 2002/03/07 03:46:53 oes - * Fixed compiler warnings etc - * - * Revision 1.47 2002/02/20 23:15:13 jongfoster - * Parsing functions now handle out-of-memory gracefully by returning - * an error code. - * - * Revision 1.46 2002/01/17 21:03:47 jongfoster - * Moving all our URL and URL pattern parsing code to urlmatch.c. - * - * Revision 1.45 2002/01/09 14:33:03 oes - * Added support for localtime_r. - * - * Revision 1.44 2001/12/14 01:22:54 steudten - * Remove 'user:pass@' from 'proto://user:pass@host' for the - * new added header 'Host: ..'. (See Req ID 491818) - * - * Revision 1.43 2001/11/23 00:26:38 jongfoster - * Fixing two really stupid errors in my previous commit - * - * Revision 1.42 2001/11/22 21:59:30 jongfoster - * Adding code to handle +no-cookies-keep - * - * Revision 1.41 2001/11/05 23:43:05 steudten - * Add time+date to log files. - * - * Revision 1.40 2001/10/26 20:13:09 jongfoster - * ctype.h is needed in Windows, too. - * - * Revision 1.39 2001/10/26 17:40:04 oes - * Introduced get_header_value() - * Removed http->user_agent, csp->referrer and csp->accept_types - * Removed client_accept() - * - * Revision 1.38 2001/10/25 03:40:48 david__schmidt - * Change in porting tactics: OS/2's EMX porting layer doesn't allow multiple - * threads to call select() simultaneously. So, it's time to do a real, live, - * native OS/2 port. See defines for __EMX__ (the porting layer) vs. __OS2__ - * (native). Both versions will work, but using __OS2__ offers multi-threading. - * - * Revision 1.37 2001/10/23 21:36:02 jongfoster - * Documenting sed()'s error behaviou (doc change only) - * - * Revision 1.36 2001/10/13 12:51:51 joergs - * Removed client_host, (was only required for the old 2.0.2-11 http://noijb. - * force-load), instead crumble Host: and add it (again) in client_host_adder - * (in case we get a HTTP/1.0 request without Host: header and forward it to - * a HTTP/1.1 server/proxy). - * - * Revision 1.35 2001/10/09 22:39:21 jongfoster - * assert.h is also required under Win32, so moving out of #ifndef _WIN32 - * block. - * - * Revision 1.34 2001/10/07 18:50:55 oes - * Added server_content_encoding, renamed server_transfer_encoding - * - * Revision 1.33 2001/10/07 18:04:49 oes - * Changed server_http11 to server_http and its pattern to "HTTP". - * Additional functionality: it now saves the HTTP status into - * csp->http->status and sets CT_TABOO for Status 206 (partial range) - * - * Revision 1.32 2001/10/07 15:43:28 oes - * Removed FEATURE_DENY_GZIP and replaced it with client_accept_encoding, - * client_te and client_accept_encoding_adder, triggered by the new - * +no-compression action. For HTTP/1.1 the Accept-Encoding header is - * changed to allow only identity and chunked, and the TE header is - * crunched. For HTTP/1.0, Accept-Encoding is crunched. - * - * parse_http_request no longer does anything than parsing. The rewriting - * of http->cmd and version mangling are gone. It now also recognizes - * the put and delete methods and saves the url in http->url. Removed - * unused variable. - * - * renamed content_type and content_length to have the server_ prefix - * - * server_content_type now only works if csp->content_type != CT_TABOO - * - * added server_transfer_encoding, which - * - Sets CT_TABOO to prohibit filtering if encoding compresses - * - Raises the CSP_FLAG_CHUNKED flag if Encoding is "chunked" - * - Change from "chunked" to "identity" if body was chunked - * but has been de-chunked for filtering. - * - * added server_content_md5 which crunches any Content-MD5 headers - * if the body was modified. - * - * made server_http11 conditional on +downgrade action - * - * Replaced 6 boolean members of csp with one bitmap (csp->flags) - * - * Revision 1.31 2001/10/05 14:25:02 oes - * Crumble Keep-Alive from Server - * - * Revision 1.30 2001/09/29 12:56:03 joergs - * IJB now changes HTTP/1.1 to HTTP/1.0 in requests and answers. - * - * Revision 1.29 2001/09/24 21:09:24 jongfoster - * Fixing 2 memory leaks that Guy spotted, where the paramater to - * enlist() was not being free()d. - * - * Revision 1.28 2001/09/22 16:32:28 jongfoster - * Removing unused #includes. - * - * Revision 1.27 2001/09/20 15:45:25 steudten - * - * add casting from size_t to int for printf() - * remove local variable shadow s2 - * - * Revision 1.26 2001/09/16 17:05:14 jongfoster - * Removing unused #include showarg.h - * - * Revision 1.25 2001/09/16 13:21:27 jongfoster - * Changes to use new list functions. - * - * Revision 1.24 2001/09/13 23:05:50 jongfoster - * Changing the string paramater to the header parsers a "const". - * - * Revision 1.23 2001/09/12 18:08:19 steudten - * - * In parse_http_request() header rewriting miss the host value, so - * from http://www.mydomain.com the result was just " / " not - * http://www.mydomain.com/ in case we forward. - * - * Revision 1.22 2001/09/10 10:58:53 oes - * Silenced compiler warnings - * - * Revision 1.21 2001/07/31 14:46:00 oes - * - Persistant connections now suppressed - * - sed() no longer appends empty header to csp->headers - * - * Revision 1.20 2001/07/30 22:08:36 jongfoster - * Tidying up #defines: - * - All feature #defines are now of the form FEATURE_xxx - * - Permanently turned off WIN_GUI_EDIT - * - Permanently turned on WEBDAV and SPLIT_PROXY_ARGS - * - * Revision 1.19 2001/07/25 17:21:54 oes - * client_uagent now saves copy of User-Agent: header value - * - * Revision 1.18 2001/07/13 14:02:46 oes - * - Included fix to repair broken HTTP requests that - * don't contain a path, not even '/'. - * - Removed all #ifdef PCRS - * - content_type now always inspected and classified as - * text, gif or other. - * - formatting / comments - * - * Revision 1.17 2001/06/29 21:45:41 oes - * Indentation, CRLF->LF, Tab-> Space - * - * Revision 1.16 2001/06/29 13:32:42 oes - * - Fixed a comment - * - Adapted free_http_request - * - Removed logentry from cancelled commit - * - * Revision 1.15 2001/06/03 19:12:38 oes - * deleted const struct interceptors - * - * Revision 1.14 2001/06/01 18:49:17 jongfoster - * Replaced "list_share" with "list" - the tiny memory gain was not - * worth the extra complexity. - * - * Revision 1.13 2001/05/31 21:30:33 jongfoster - * Removed list code - it's now in list.[ch] - * Renamed "permission" to "action", and changed many features - * to use the actions file rather than the global config. - * - * Revision 1.12 2001/05/31 17:33:13 oes - * - * CRLF -> LF - * - * Revision 1.11 2001/05/29 20:11:19 joergs - * '/ * inside comment' warning removed. - * - * Revision 1.10 2001/05/29 09:50:24 jongfoster - * Unified blocklist/imagelist/permissionslist. - * File format is still under discussion, but the internal changes - * are (mostly) done. - * - * Also modified interceptor behaviour: - * - We now intercept all URLs beginning with one of the following - * prefixes (and *only* these prefixes): - * * http://i.j.b/ - * * http://ijbswa.sf.net/config/ - * * http://ijbswa.sourceforge.net/config/ - * - New interceptors "home page" - go to http://i.j.b/ to see it. - * - Internal changes so that intercepted and fast redirect pages - * are not replaced with an image. - * - Interceptors now have the option to send a binary page direct - * to the client. (i.e. ijb-send-banner uses this) - * - Implemented show-url-info interceptor. (Which is why I needed - * the above interceptors changes - a typical URL is - * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif". - * The previous mechanism would not have intercepted that, and - * if it had been intercepted then it then it would have replaced - * it with an image.) - * - * Revision 1.9 2001/05/28 17:26:33 jongfoster - * Fixing segfault if last header was crunched. - * Fixing Windows build (snprintf() is _snprintf() under Win32, but we - * can use the cross-platform sprintf() instead.) - * - * Revision 1.8 2001/05/27 22:17:04 oes - * - * - re_process_buffer no longer writes the modified buffer - * to the client, which was very ugly. It now returns the - * buffer, which it is then written by chat. - * - * - content_length now adjusts the Content-Length: header - * for modified documents rather than crunch()ing it. - * (Length info in csp->content_length, which is 0 for - * unmodified documents) - * - * - For this to work, sed() is called twice when filtering. - * - * Revision 1.7 2001/05/27 13:19:06 oes - * Patched Joergs solution for the content-length in. - * - * Revision 1.6 2001/05/26 13:39:32 jongfoster - * Only crunches Content-Length header if applying RE filtering. - * Without this fix, Microsoft Windows Update wouldn't work. - * - * Revision 1.5 2001/05/26 00:28:36 jongfoster - * Automatic reloading of config file. - * Removed obsolete SIGHUP support (Unix) and Reload menu option (Win32). - * Most of the global variables have been moved to a new - * struct configuration_spec, accessed through csp->config->globalname - * Most of the globals remaining are used by the Win32 GUI. - * - * Revision 1.4 2001/05/22 18:46:04 oes - * - * - Enabled filtering banners by size rather than URL - * by adding patterns that replace all standard banner - * sizes with the "Junkbuster" gif to the re_filterfile - * - * - Enabled filtering WebBugs by providing a pattern - * which kills all 1x1 images - * - * - Added support for PCRE_UNGREEDY behaviour to pcrs, - * which is selected by the (nonstandard and therefore - * capital) letter 'U' in the option string. - * It causes the quantifiers to be ungreedy by default. - * Appending a ? turns back to greedy (!). - * - * - Added a new interceptor ijb-send-banner, which - * sends back the "Junkbuster" gif. Without imagelist or - * MSIE detection support, or if tinygif = 1, or the - * URL isn't recognized as an imageurl, a lame HTML - * explanation is sent instead. - * - * - Added new feature, which permits blocking remote - * script redirects and firing back a local redirect - * to the browser. - * The feature is conditionally compiled, i.e. it - * can be disabled with --disable-fast-redirects, - * plus it must be activated by a "fast-redirects" - * line in the config file, has its own log level - * and of course wants to be displayed by show-proxy-args - * Note: Boy, all the #ifdefs in 1001 locations and - * all the fumbling with configure.in and acconfig.h - * were *way* more work than the feature itself :-( - * - * - Because a generic redirect template was needed for - * this, tinygif = 3 now uses the same. - * - * - Moved GIFs, and other static HTTP response templates - * to project.h - * - * - Some minor fixes - * - * - Removed some >400 CRs again (Jon, you really worked - * a lot! ;-) - * - * Revision 1.3 2001/05/20 01:21:20 jongfoster - * Version 2.9.4 checkin. - * - Merged popupfile and cookiefile, and added control over PCRS - * filtering, in new "permissionsfile". - * - Implemented LOG_LEVEL_FATAL, so that if there is a configuration - * file error you now get a message box (in the Win32 GUI) rather - * than the program exiting with no explanation. - * - Made killpopup use the PCRS MIME-type checking and HTTP-header - * skipping. - * - Removed tabs from "config" - * - Moved duplicated url parsing code in "loaders.c" to a new funcition. - * - Bumped up version number. - * - * Revision 1.2 2001/05/17 23:02:36 oes - * - Made referrer option accept 'L' as a substitute for 'ยง' - * - * Revision 1.1.1.1 2001/05/15 13:59:01 oes - * Initial import of version 2.9.3 source tree - * - * *********************************************************************/ - + #include "config.h" @@ -375,25 +57,56 @@ const char parsers_rcs[] = "$Id: parsers.c,v 1.50 2002/03/12 01:45:35 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 + +#define GZIP_IDENTIFIER_1 0x1f +#define GZIP_IDENTIFIER_2 0x8b + +#define GZIP_FLAG_CHECKSUM 0x02 +#define GZIP_FLAG_EXTRA_FIELDS 0x04 +#define GZIP_FLAG_FILE_NAME 0x08 +#define GZIP_FLAG_COMMENT 0x10 +#define GZIP_FLAG_RESERVED_BITS 0xe0 +#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". @@ -404,56 +117,154 @@ 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_ZLIB +static jb_err server_adjust_content_encoding(struct client_state *csp, char **header); +#endif + +#ifdef FEATURE_CONNECTION_KEEP_ALIVE +static jb_err server_save_content_length(struct client_state *csp, char **header); +static jb_err server_keep_alive(struct client_state *csp, char **header); +static jb_err server_proxy_connection(struct client_state *csp, char **header); +static jb_err client_keep_alive(struct client_state *csp, char **header); +static jb_err client_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_adder(struct client_state *csp); +#ifdef FEATURE_CONNECTION_KEEP_ALIVE +static jb_err server_proxy_connection_adder(struct client_state *csp); +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + +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 void create_content_length_header(unsigned long long content_length, + char *header, size_t buffer_length); + +/* + * 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 }, +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + { "Keep-Alive:", 11, client_keep_alive }, + { "Content-Length:", 15, client_save_content_length }, +#else { "Keep-Alive:", 11, crumble }, - { "connection:", 11, crumble }, +#endif + { "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 }, + { "Keep-Alive:", 11, server_keep_alive }, + { "Proxy-Connection:", 17, server_proxy_connection }, +#else + { "Keep-Alive:", 11, crumble }, +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + { "Transfer-Encoding:", 18, server_transfer_coding }, + { "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_adder, +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + server_proxy_connection_adder, +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ NULL }; - /********************************************************************* * * Function : flush_socket @@ -462,7 +273,7 @@ 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, @@ -472,10 +283,9 @@ const add_header_func_ptr add_server_headers[] = { * file, the results are not portable. * *********************************************************************/ -int flush_socket(jb_socket fd, struct client_state *csp) +long flush_socket(jb_socket fd, struct iob *iob) { - struct iob *iob = csp->iob; - int len = iob->eod - iob->cur; + long len = iob->eod - iob->cur; if (len <= 0) { @@ -496,166 +306,708 @@ int flush_socket(jb_socket fd, struct client_state *csp) * * Function : add_to_iob * - * Description : Add content to the buffered page. + * Description : Add content to the buffered page, expanding the + * buffer if necessary. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * 2 : buf = holds the content to be added to the page * 3 : n = number of bytes to be added * - * Returns : None + * Returns : JB_ERR_OK on success, JB_ERR_MEMORY if out-of-memory + * or buffer limit reached. * *********************************************************************/ -void add_to_iob(struct client_state *csp, char *buf, int n) +jb_err add_to_iob(struct client_state *csp, char *buf, long n) { struct iob *iob = csp->iob; - size_t have, need; + size_t used, offset, need; char *p; - have = iob->eod - iob->cur; - - if (n <= 0) - { - return; - } + if (n <= 0) return JB_ERR_OK; - need = have + n; + used = (size_t)(iob->eod - iob->buf); + offset = (size_t)(iob->cur - iob->buf); + need = used + (size_t)n + 1; - if ((p = (char *)malloc(need + 1)) == NULL) + /* + * If the buffer can't hold the new data, extend it first. + * Use the next power of two if possible, else use the actual need. + */ + if (need > csp->config->buffer_limit) { - log_error(LOG_LEVEL_FATAL, "malloc() iob failed: %E"); + log_error(LOG_LEVEL_INFO, + "Buffer limit reached while extending the buffer (iob). Needed: %d. Limit: %d", + need, csp->config->buffer_limit); + return JB_ERR_MEMORY; } - if (have) + if (need > iob->size) { - /* there is something in the buffer - save it */ - memcpy(p, iob->cur, have); + size_t want = csp->iob->size ? csp->iob->size : 512; - /* replace the buffer with the new space */ - freez(iob->buf); - iob->buf = p; + while (want <= need) + { + want *= 2; + } + + if (want <= csp->config->buffer_limit && NULL != (p = (char *)realloc(iob->buf, want))) + { + iob->size = want; + } + else if (NULL != (p = (char *)realloc(iob->buf, need))) + { + iob->size = need; + } + else + { + log_error(LOG_LEVEL_ERROR, "Extending the buffer (iob) failed: %E"); + return JB_ERR_MEMORY; + } - /* point to the end of the data */ - p += have; - } - else - { - /* the buffer is empty, free it and reinitialize */ - freez(iob->buf); + /* Update the iob pointers */ + iob->cur = p + offset; + iob->eod = p + used; iob->buf = p; } /* copy the new data into the iob buffer */ - memcpy(p, buf, (size_t)n); + memcpy(iob->eod, buf, (size_t)n); /* point to the end of the data */ - p += n; + iob->eod += n; /* null terminate == cheap insurance */ - *p = '\0'; - - /* set the pointers to the new values */ - iob->cur = iob->buf; - iob->eod = p; + *iob->eod = '\0'; - return; + return JB_ERR_OK; } +#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; + char *buf; /* new, uncompressed buffer */ + char *cur; /* Current iob position (to keep the original + * iob->cur unmodified if we return early) */ + size_t bufsize; /* allocated size of the new buffer */ + size_t old_size; /* Content size before decompression */ + size_t skip_size; /* Number of bytes at the beginning of the iob + that we should NOT decompress. */ + int status; /* return status of the inflate() call */ + z_stream zstr; /* used by calls to zlib */ + + assert(csp->iob->cur - csp->iob->buf > 0); + assert(csp->iob->eod - csp->iob->cur > 0); + + bufsize = csp->iob->size; + skip_size = (size_t)(csp->iob->cur - csp->iob->buf); + old_size = (size_t)(csp->iob->eod - csp->iob->cur); + + cur = csp->iob->cur; + + if (bufsize < (size_t)10) + { + /* + * This is to protect the parsing of gzipped data, + * but it should(?) be valid for deflated data also. + */ + log_error(LOG_LEVEL_ERROR, "Buffer too small decompressing iob"); + return JB_ERR_COMPRESS; + } - if ((iob->cur == NULL) - || ((p = strchr(iob->cur, '\n')) == NULL)) + if (csp->content_type & CT_GZIP) { - return(""); /* couldn't find a complete 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. + */ + + /* + * Strip off the gzip header. Please see RFC 1952 for more + * explanation of the appropriate fields. + */ + if (((*cur++ & 0xff) != GZIP_IDENTIFIER_1) + || ((*cur++ & 0xff) != GZIP_IDENTIFIER_2) + || (*cur++ != Z_DEFLATED)) + { + log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing"); + return JB_ERR_COMPRESS; + } + else + { + int flags = *cur++; + if (flags & GZIP_FLAG_RESERVED_BITS) + { + /* The gzip header has reserved bits set; bail out. */ + log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing"); + return JB_ERR_COMPRESS; + } + + /* + * Skip mtime (4 bytes), extra flags (1 byte) + * and OS type (1 byte). + */ + cur += 6; + + /* Skip extra fields if necessary. */ + if (flags & GZIP_FLAG_EXTRA_FIELDS) + { + /* + * Skip a given number of bytes, specified + * as a 16-bit little-endian value. + * + * XXX: this code is untested and should probably be removed. + */ + int skip_bytes; + skip_bytes = *cur++; + skip_bytes += *cur++ << 8; + + /* + * The number of bytes to skip should be positive + * and we'd like to stay in the buffer. + */ + if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur))) + { + log_error(LOG_LEVEL_ERROR, + "Unreasonable amount of bytes to skip (%d). Stopping decompression", + skip_bytes); + return JB_ERR_COMPRESS; + } + log_error(LOG_LEVEL_INFO, + "Skipping %d bytes for gzip compression. Does this sound right?", + skip_bytes); + cur += skip_bytes; + } + + /* Skip the filename if necessary. */ + if (flags & GZIP_FLAG_FILE_NAME) + { + /* A null-terminated string is supposed to follow. */ + while (*cur++ && (cur < csp->iob->eod)); + } + + /* Skip the comment if necessary. */ + if (flags & GZIP_FLAG_COMMENT) + { + /* A null-terminated string is supposed to follow. */ + while (*cur++ && (cur < csp->iob->eod)); + } + + /* Skip the CRC if necessary. */ + if (flags & GZIP_FLAG_CHECKSUM) + { + cur += 2; + } + + if (cur >= csp->iob->eod) + { + /* + * If the current position pointer reached or passed + * the buffer end, we were obviously tricked to skip + * too much. + */ + log_error(LOG_LEVEL_ERROR, + "Malformed gzip header detected. Aborting decompression."); + return JB_ERR_COMPRESS; + } + } + } + else if (csp->content_type & CT_DEFLATE) + { + /* + * XXX: The debug level should be lowered + * before the next stable release. + */ + log_error(LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur); + /* + * In theory (that is, according to RFC 1950), deflate-compressed + * data should begin with a two-byte zlib header and have an + * adler32 checksum at the end. It seems that in practice only + * the raw compressed data is sent. Note that this means that + * we are not RFC 1950-compliant here, but the advantage is that + * this actually works. :) + * + * We add a dummy null byte to tell zlib where the data ends, + * and later inform it not to expect a header. + * + * Fortunately, add_to_iob() has thoughtfully null-terminated + * the buffer; we can just increment the end pointer to include + * the dummy byte. + */ + csp->iob->eod++; + } + else + { + log_error(LOG_LEVEL_ERROR, + "Unable to determine compression format for decompression"); + return JB_ERR_COMPRESS; } - *p = '\0'; + /* 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; - ret = strdup(iob->cur); - if (ret == NULL) + /* + * Passing -MAX_WBITS to inflateInit2 tells the library + * that there is no zlib header. + */ + if (inflateInit2(&zstr, -MAX_WBITS) != Z_OK) { - /* FIXME No way to handle error properly */ - log_error(LOG_LEVEL_FATAL, "Out of memory in get_header()"); + log_error(LOG_LEVEL_ERROR, "Error initializing decompression"); + return JB_ERR_COMPRESS; } - iob->cur = p+1; + /* + * 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; + } - if ((q = strchr(ret, '\r')) != NULL) *q = '\0'; + assert(bufsize >= skip_size); + memcpy(buf, csp->iob->buf, skip_size); + zstr.avail_out = (uInt)(bufsize - skip_size); + zstr.next_out = (Bytef *)buf + skip_size; - /* is this a blank linke (i.e. the end of the header) ? */ - if (*ret == '\0') + /* Try to decompress the whole stream in one shot. */ + while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH))) { - freez(ret); - return(NULL); + /* 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 (0 == zstr.avail_in) + { + /* + * If zlib wants more data then there's a problem, because + * the complete compressed file should have been buffered. + */ + log_error(LOG_LEVEL_ERROR, + "Unexpected end of compressed iob. Using what we got so far."); + break; + } + + /* + * If we tried the limit and still didn't have enough + * memory, just give up. + */ + if (bufsize == csp->config->buffer_limit) + { + log_error(LOG_LEVEL_ERROR, "Buffer limit reached while decompressing iob"); + return JB_ERR_MEMORY; + } + + /* Try doubling the buffer size each time. */ + bufsize *= 2; + + /* Don't exceed the buffer limit. */ + if (bufsize > csp->config->buffer_limit) + { + bufsize = csp->config->buffer_limit; + } + + /* Try to allocate the new buffer. */ + tmpbuf = realloc(buf, bufsize); + if (NULL == tmpbuf) + { + log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob"); + freez(buf); + return JB_ERR_MEMORY; + } + else + { + char *oldnext_out = (char *)zstr.next_out; + + /* + * Update the fields for inflate() to use the new + * buffer, which may be in a location different from + * the old one. + */ + zstr.avail_out += (uInt)(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)); + + buf = tmpbuf; + } + } + + if (Z_STREAM_ERROR == inflateEnd(&zstr)) + { + log_error(LOG_LEVEL_ERROR, + "Inconsistent stream state after decompression: %s", zstr.msg); + /* + * XXX: Intentionally no return. + * + * According to zlib.h, Z_STREAM_ERROR is returned + * "if the stream state was inconsistent". + * + * I assume in this case inflate()'s status + * would also be something different than Z_STREAM_END + * so this check should be redundant, but lets see. + */ + } + + if ((status != Z_STREAM_END) && (0 != zstr.avail_in)) + { + /* + * We failed to decompress the stream and it's + * not simply because of missing data. + */ + log_error(LOG_LEVEL_ERROR, + "Unexpected error while decompressing to the buffer (iob): %s", + zstr.msg); + return JB_ERR_COMPRESS; + } + + /* + * Finally, we can actually update the iob, since the + * decompression was successful. First, free the old + * buffer. + */ + freez(csp->iob->buf); + + /* Now, update the iob to use the new buffer. */ + csp->iob->buf = buf; + csp->iob->cur = csp->iob->buf + skip_size; + csp->iob->eod = (char *)zstr.next_out; + csp->iob->size = bufsize; + + /* + * Make sure the new uncompressed iob obeys some minimal + * consistency conditions. + */ + if ((csp->iob->buf < csp->iob->cur) + && (csp->iob->cur <= csp->iob->eod) + && (csp->iob->eod <= csp->iob->buf + csp->iob->size)) + { + const size_t new_size = (size_t)(csp->iob->eod - csp->iob->cur); + if (new_size > (size_t)0) + { + log_error(LOG_LEVEL_RE_FILTER, + "Decompression successful. Old size: %d, new size: %d.", + old_size, new_size); + } + else + { + /* zlib thinks this is OK, so lets do the same. */ + log_error(LOG_LEVEL_INFO, "Decompression didn't result in any content."); + } + } + else + { + /* It seems that zlib did something weird. */ + log_error(LOG_LEVEL_ERROR, + "Unexpected error decompressing the buffer (iob): %d==%d, %d>%d, %d<%d", + csp->iob->cur, csp->iob->buf + skip_size, csp->iob->eod, csp->iob->buf, + csp->iob->eod, csp->iob->buf + csp->iob->size); + return JB_ERR_COMPRESS; } - return(ret); + return JB_ERR_OK; } +#endif /* defined(FEATURE_ZLIB) */ /********************************************************************* * - * Function : get_header_value + * Function : string_move * - * 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. + * 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 : header_list = pointer to list - * 2 : header_name = string with name of header to look for. - * Trailing colon required, capitalization - * doesn't matter. + * 1 : dst = Destination to overwrite + * 2 : src = Source to move. * - * Returns : NULL if not found, else value of header + * Returns : N/A * *********************************************************************/ -char *get_header_value(const struct list *header_list, const char *header_name) +static void string_move(char *dst, char *src) { - struct list_entry *cur_entry; - char *ret = NULL; - size_t length = 0; + assert(dst < src); - assert(header_list); - assert(header_name); - length = strlen(header_name); + /* +1 to copy the terminating nul as well. */ + memmove(dst, src, strlen(src)+1); +} - for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next) - { - if (cur_entry->str) - { + +/********************************************************************* + * + * Function : normalize_lws + * + * Description : Reduces unquoted linear white space in headers + * to a single space in accordance with RFC 2616 2.2. + * This simplifies parsing and filtering later on. + * + * XXX: Remove log messages before + * the next stable release? + * + * Parameters : + * 1 : header = A header with linear white space to reduce. + * + * Returns : N/A + * + *********************************************************************/ +static void normalize_lws(char *header) +{ + char *p = header; + + while (*p != '\0') + { + if (ijb_isspace(*p) && ijb_isspace(*(p+1))) + { + char *q = p+1; + + while (ijb_isspace(*q)) + { + q++; + } + log_error(LOG_LEVEL_HEADER, "Reducing white space in '%s'", header); + string_move(p+1, q); + } + + if (*p == '\t') + { + log_error(LOG_LEVEL_HEADER, + "Converting tab to space in '%s'", header); + *p = ' '; + } + else if (*p == '"') + { + char *end_of_token = strstr(p+1, "\""); + + if (NULL != end_of_token) + { + /* Don't mess with quoted text. */ + p = end_of_token; + } + else + { + log_error(LOG_LEVEL_HEADER, + "Ignoring single quote in '%s'", header); + } + } + p++; + } + + p = strchr(header, ':'); + if ((p != NULL) && (p != header) && ijb_isspace(*(p-1))) + { + /* + * There's still space before the colon. + * We don't want it. + */ + string_move(p-1, p); + } +} + + +/********************************************************************* + * + * Function : get_header + * + * Description : This (odd) routine will parse the csp->iob + * to get the next complete header. + * + * Parameters : + * 1 : iob = The I/O buffer to parse, usually csp->iob. + * + * Returns : Any one of the following: + * + * 1) a pointer to a dynamically allocated string that contains a header line + * 2) NULL indicating that the end of the header was reached + * 3) "" indicating that the end of the iob was reached before finding + * a complete header line. + * + *********************************************************************/ +char *get_header(struct iob *iob) +{ + char *header; + + header = get_header_line(iob); + + if ((header == NULL) || (*header == '\0')) + { + /* + * No complete header read yet, tell the client. + */ + return header; + } + + while ((iob->cur[0] == ' ') || (iob->cur[0] == '\t')) + { + /* + * Header spans multiple lines, append the next one. + */ + char *continued_header; + + continued_header = get_header_line(iob); + if ((continued_header == NULL) || (*continued_header == '\0')) + { + /* + * No complete header read yet, return what we got. + * XXX: Should "unread" header instead. + */ + log_error(LOG_LEVEL_INFO, + "Failed to read a multi-line header properly: '%s'", + header); + break; + } + + if (JB_ERR_OK != string_join(&header, continued_header)) + { + log_error(LOG_LEVEL_FATAL, + "Out of memory while appending multiple headers."); + } + else + { + /* XXX: remove before next stable release. */ + log_error(LOG_LEVEL_HEADER, + "Merged multiple header lines to: '%s'", + header); + } + } + + normalize_lws(header); + + return header; + +} + + +/********************************************************************* + * + * Function : get_header_line + * + * Description : This (odd) routine will parse the csp->iob + * to get the next header line. + * + * Parameters : + * 1 : iob = The I/O buffer to parse, usually csp->iob. + * + * Returns : Any one of the following: + * + * 1) a pointer to a dynamically allocated string that contains a header line + * 2) NULL indicating that the end of the header was reached + * 3) "" indicating that the end of the iob was reached before finding + * a complete header line. + * + *********************************************************************/ +static char *get_header_line(struct iob *iob) +{ + char *p, *q, *ret; + + if ((iob->cur == NULL) + || ((p = strchr(iob->cur, '\n')) == NULL)) + { + return(""); /* couldn't find a complete header */ + } + + *p = '\0'; + + ret = strdup(iob->cur); + if (ret == NULL) + { + /* FIXME No way to handle error properly */ + log_error(LOG_LEVEL_FATAL, "Out of memory in get_header_line()"); + } + assert(ret != NULL); + + iob->cur = p+1; + + if ((q = strchr(ret, '\r')) != NULL) *q = '\0'; + + /* is this a blank line (i.e. the end of the header) ? */ + if (*ret == '\0') + { + freez(ret); + return NULL; + } + + return ret; + +} + + +/********************************************************************* + * + * Function : get_header_value + * + * Description : Get the value of a given header from a chained list + * of header lines or return NULL if no such header is + * present in the list. + * + * Parameters : + * 1 : header_list = pointer to list + * 2 : header_name = string with name of header to look for. + * Trailing colon required, capitalization + * doesn't matter. + * + * Returns : NULL if not found, else value of header + * + *********************************************************************/ +char *get_header_value(const struct list *header_list, const char *header_name) +{ + struct list_entry *cur_entry; + char *ret = NULL; + size_t length = 0; + + assert(header_list); + assert(header_name); + length = strlen(header_name); + + for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next) + { + if (cur_entry->str) + { if (!strncmpic(cur_entry->str, header_name, length)) { /* * Found: return pointer to start of value */ - ret = (char *) (cur_entry->str + length); + ret = cur_entry->str + length; while (*ret && ijb_isspace(*ret)) ret++; - return(ret); + return ret; } } } @@ -667,6 +1019,36 @@ char *get_header_value(const struct list *header_list, const char *header_name) } + +/********************************************************************* + * + * 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 @@ -680,63 +1062,1170 @@ char *get_header_value(const struct list *header_list, const char *header_name) * 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...) + * 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. * - * Returns : Single pointer to a fully formed header, or NULL - * 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_adjust_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)); + } + } + } + } + +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + if ((JB_ERR_OK == err) + && (csp->flags & CSP_FLAG_MODIFIED) + && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE) + && !(csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET)) + { + char header[50]; + + create_content_length_header(csp->content_length, header, sizeof(header)); + err = enlist(csp->headers, header); + if (JB_ERR_OK == err) + { + log_error(LOG_LEVEL_HEADER, + "Content modified with no Content-Length header set. " + "Created: %s.", header); + } + } +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + + 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; + + 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; + } + + if (filters_available(csp) == FALSE) + { + log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: " + "tagging enabled, but no taggers available."); + return JB_ERR_OK; + } + + for (i = 0; i < MAX_AF_FILES; i++) + { + fl = csp->rlist[i]; + if ((NULL == fl) || (NULL == fl->f)) + { + /* + * Either there are no filter files + * left, or this filter file just + * contains no valid filters. + * + * Continue to be sure we don't miss + * valid filter files that are chained + * after empty or invalid ones. + */ + continue; + } + + /* For all filters, */ + for (b = fl->f; b; b = b->next) + { + if (b->type != wanted_filter_type) + { + /* skip the ones we don't care about, */ + continue; + } + /* leaving only taggers that could apply, of which we use the ones, */ + for (tag_name = csp->action->multi[multi_action_index]->first; + NULL != tag_name; tag_name = tag_name->next) + { + /* that do apply, and */ + if (strcmp(b->name, tag_name->str) == 0) + { + char *modified_tag = NULL; + char *tag = header; + size_t size = header_length; + pcrs_job *joblist = b->joblist; + + if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b); + + if (NULL == joblist) + { + log_error(LOG_LEVEL_RE_FILTER, + "Tagger %s has empty joblist. Nothing to do.", b->name); + continue; + } + + /* execute their pcrs_joblist on the header. */ + for (job = joblist; NULL != job; job = job->next) + { + const int hits = pcrs_execute(job, tag, size, &modified_tag, &size); + + if (0 < hits) + { + /* Success, continue with the modified version. */ + if (tag != header) + { + freez(tag); + } + tag = modified_tag; + } + else + { + /* Tagger doesn't match */ + if (0 > hits) + { + /* Regex failure, log it but continue anyway. */ + assert(NULL != header); + log_error(LOG_LEVEL_ERROR, + "Problems with tagger \'%s\' and header \'%s\': %s", + b->name, *header, pcrs_strerror(hits)); + } + freez(modified_tag); + } + } + + if (b->dynamic) pcrs_free_joblist(joblist); + + /* If this tagger matched */ + if (tag != header) + { + if (0 == size) + { + /* + * There is to technical limitation which makes + * it impossible to use empty tags, but I assume + * no one would do it intentionally. + */ + freez(tag); + log_error(LOG_LEVEL_INFO, + "Tagger \'%s\' created an empty tag. Ignored.", + b->name); + continue; + } + + if (!list_contains_item(csp->tags, tag)) + { + if (JB_ERR_OK != enlist(csp->tags, tag)) + { + log_error(LOG_LEVEL_ERROR, + "Insufficient memory to add tag \'%s\', " + "based on tagger \'%s\' and header \'%s\'", + tag, b->name, *header); + } + else + { + char *action_message; + /* + * update the action bits right away, to make + * tagging based on tags set by earlier taggers + * of the same kind possible. + */ + if (update_action_bits_for_tag(csp, tag)) + { + action_message = "Action bits updated accordingly."; + } + else + { + action_message = "No action bits update necessary."; + } + + log_error(LOG_LEVEL_HEADER, + "Tagger \'%s\' added tag \'%s\'. %s", + b->name, tag, action_message); + } + } + else + { + /* XXX: Is this log-worthy? */ + log_error(LOG_LEVEL_HEADER, + "Tagger \'%s\' didn't add tag \'%s\'. " + "Tag already present", b->name, tag); + } + freez(tag); + } /* if the tagger matched */ + } /* if the tagger applies */ + } /* for every tagger that could apply */ + } /* for all filters */ + } /* for all filter files */ + + return JB_ERR_OK; +} + +/* here begins the family of parser functions that reformat header lines */ + +/********************************************************************* + * + * Function : filter_header + * + * Description : Executes all text substitutions from all applying + * +(server|client)-header-filter actions on the header. + * Most of the code was copied from pcrs_filter_response, + * including the rather short variable names + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success and always succeeds + * + *********************************************************************/ +static jb_err filter_header(struct client_state *csp, char **header) +{ + int hits=0; + int matches; + size_t size = strlen(*header); + + char *newheader = NULL; + pcrs_job *job; + + struct file_list *fl; + struct re_filterfile_spec *b; + struct list_entry *filtername; + + int i; + 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; + } + + if (filters_available(csp) == FALSE) + { + 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 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 server_connection(struct client_state *csp, char **header) +{ + if (!strcmpic(*header, "Connection: keep-alive") +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED) +#endif + ) + { +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)) + { + csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE; + } + + if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)) + { + log_error(LOG_LEVEL_HEADER, + "Keeping the server header '%s' around.", *header); + } + else +#endif /* FEATURE_CONNECTION_KEEP_ALIVE */ + { + char *old_header = *header; + + *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_adder() to return early. */ + csp->flags |= CSP_FLAG_SERVER_CONNECTION_HEADER_SET; + + return JB_ERR_OK; +} + + +#ifdef FEATURE_CONNECTION_KEEP_ALIVE +/********************************************************************* + * + * Function : server_keep_alive + * + * Description : Stores the server's keep alive timeout. + * + * 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 server_keep_alive(struct client_state *csp, char **header) +{ + unsigned int keep_alive_timeout; + const char *timeout_position = strstr(*header, "timeout="); + + if ((NULL == timeout_position) + || (1 != sscanf(timeout_position, "timeout=%u", &keep_alive_timeout))) + { + log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header); + } + else + { + if (keep_alive_timeout < csp->server_connection.keep_alive_timeout) + { + log_error(LOG_LEVEL_HEADER, + "Reducing keep-alive timeout from %u to %u.", + csp->server_connection.keep_alive_timeout, keep_alive_timeout); + csp->server_connection.keep_alive_timeout = keep_alive_timeout; + } + else + { + /* XXX: Is this log worthy? */ + log_error(LOG_LEVEL_HEADER, + "Server keep-alive timeout is %u. Sticking with %u.", + keep_alive_timeout, csp->server_connection.keep_alive_timeout); + } + csp->flags |= CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET; + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : server_proxy_connection + * + * Description : Figures out whether or not we should add a + * Proxy-Connection 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. + * + *********************************************************************/ +static jb_err server_proxy_connection(struct client_state *csp, char **header) +{ + csp->flags |= CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET; + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : client_keep_alive + * + * Description : Stores the client's keep alive timeout. + * + * 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_keep_alive(struct client_state *csp, char **header) +{ + unsigned int keep_alive_timeout; + const char *timeout_position = strstr(*header, ": "); + + if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)) + { + log_error(LOG_LEVEL_HEADER, + "keep-alive support is disabled. Crunching: %s.", *header); + freez(*header); + return JB_ERR_OK; + } + + if ((NULL == timeout_position) + || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout))) + { + log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header); + } + else + { + if (keep_alive_timeout < csp->config->keep_alive_timeout) + { + log_error(LOG_LEVEL_HEADER, + "Reducing keep-alive timeout from %u to %u.", + csp->config->keep_alive_timeout, keep_alive_timeout); + csp->server_connection.keep_alive_timeout = keep_alive_timeout; + } + else + { + /* XXX: Is this log worthy? */ + log_error(LOG_LEVEL_HEADER, + "Client keep-alive timeout is %u. Sticking with %u.", + keep_alive_timeout, csp->config->keep_alive_timeout); + } + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : get_content_length + * + * Description : Gets the content length specified in a + * Content-Length header. + * + * Parameters : + * 1 : header = The Content-Length header. + * 2 : length = Storage to return the value. + * + * Returns : JB_ERR_OK on success, or + * JB_ERR_PARSE if no value is recognized. + * + *********************************************************************/ +static jb_err get_content_length(const char *header, unsigned long long *length) +{ + assert(header[14] == ':'); + +#ifdef _WIN32 + assert(sizeof(unsigned long long) > 4); + if (1 != sscanf(header+14, ": %I64u", length)) +#else + if (1 != sscanf(header+14, ": %llu", length)) +#endif + { + return JB_ERR_PARSE; + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : client_save_content_length + * + * Description : Save the Content-Length sent by the client. + * + * 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_save_content_length(struct client_state *csp, char **header) +{ + unsigned long long content_length = 0; + + assert(*(*header+14) == ':'); + + if (JB_ERR_OK != get_content_length(*header, &content_length)) + { + log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header); + freez(*header); + } + else + { + csp->expected_client_content_length = content_length; + } + + return JB_ERR_OK; +} +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + + + +/********************************************************************* + * + * 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) +{ + static const char connection_close[] = "Connection: close"; + + if (!strcmpic(*header, connection_close)) + { +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)) + { + if (!strcmpic(csp->http->ver, "HTTP/1.1")) + { + log_error(LOG_LEVEL_HEADER, + "Removing \'%s\' to imply keep-alive.", *header); + freez(*header); + } + else + { + char *old_header = *header; + + *header = strdup("Connection: keep-alive"); + if (header == NULL) + { + return JB_ERR_MEMORY; + } + log_error(LOG_LEVEL_HEADER, + "Replaced: \'%s\' with \'%s\'", old_header, *header); + freez(old_header); + } + } + else + { + log_error(LOG_LEVEL_HEADER, + "Keeping the client header '%s' around. " + "The connection will not be kept alive.", + *header); + csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE; + } + } + else if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)) + { + log_error(LOG_LEVEL_HEADER, + "Keeping the client header '%s' around. " + "The server connection will be kept alive if possible.", + *header); + csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE; +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ + } + else + { + char *old_header = *header; + + *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 client_connection_adder() to return early. */ + csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET; + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : crumble + * + * Description : This is called if a header matches a pattern to "crunch" + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success, or + * JB_ERR_MEMORY on out-of-memory error. + * + *********************************************************************/ +static jb_err crumble(struct client_state *csp, char **header) +{ + (void)csp; + log_error(LOG_LEVEL_HEADER, "crumble crunched: %s!", *header); + freez(*header); + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : crunch_server_header + * + * Description : Crunch server header if it matches a string supplied by the + * user. Called from `sed'. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success and always succeeds + * + *********************************************************************/ +static jb_err crunch_server_header(struct client_state *csp, char **header) +{ + const char *crunch_pattern; + + /* Do we feel like crunching? */ + if ((csp->action->flags & ACTION_CRUNCH_SERVER_HEADER)) + { + crunch_pattern = csp->action->string[ACTION_STRING_SERVER_HEADER]; + + /* Is the current header the lucky one? */ + if (strstr(*header, crunch_pattern)) + { + log_error(LOG_LEVEL_HEADER, "Crunching server header: %s (contains: %s)", *header, crunch_pattern); + freez(*header); + } + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : server_content_type + * + * Description : Set the content-type for filterable types (text/.*, + * .*xml.*, .*script.* 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, "script")) + { + csp->content_type |= CT_TEXT; + } + else if (strstr(*header, "image/gif")) + { + csp->content_type |= CT_GIF; + } + } + + /* + * Are we messing with the content type? + */ + if (csp->action->flags & ACTION_CONTENT_TYPE_OVERWRITE) + { + /* + * Make sure the user doesn't accidently + * change the content type of binary documents. + */ + if ((csp->content_type & CT_TEXT) || (csp->action->flags & ACTION_FORCE_TEXT_MODE)) + { + freez(*header); + *header = strdup("Content-Type: "); + string_append(header, csp->action->string[ACTION_STRING_CONTENT_TYPE]); + + if (header == NULL) + { + log_error(LOG_LEVEL_HEADER, "Insufficient memory to replace Content-Type!"); + return JB_ERR_MEMORY; + } + log_error(LOG_LEVEL_HEADER, "Modified: %s!", *header); + } + else + { + log_error(LOG_LEVEL_HEADER, "%s not replaced. " + "It doesn't look like a content type that should be filtered. " + "Enable force-text-mode if you know what you're doing.", *header); + } + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : server_transfer_coding + * + * Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses + * - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked" + * - Remove header if body was chunked but has been + * de-chunked for filtering. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success, or + * JB_ERR_MEMORY on out-of-memory error. + * + *********************************************************************/ +static jb_err server_transfer_coding(struct client_state *csp, char **header) +{ + /* + * Turn off pcrs and gif filtering if body compressed + */ + if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate")) + { +#ifdef FEATURE_ZLIB + /* + * XXX: Added to test if we could use CT_GZIP and CT_DEFLATE here. + */ + log_error(LOG_LEVEL_INFO, "Marking content type for %s as CT_TABOO because of %s.", + csp->http->cmd, *header); +#endif /* def FEATURE_ZLIB */ + csp->content_type = CT_TABOO; + } + + /* + * Raise flag if body chunked + */ + if (strstr(*header, "chunked")) + { + csp->flags |= CSP_FLAG_CHUNKED; + + /* + * If the body was modified, it has been de-chunked first + * and the header must be removed. + * + * FIXME: If there is more than one transfer encoding, + * only the "chunked" part should be removed here. + */ + if (csp->flags & CSP_FLAG_MODIFIED) + { + log_error(LOG_LEVEL_HEADER, "Removing: %s", *header); + freez(*header); + } + } + + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : server_content_encoding + * + * Description : Used to check if the content is compressed, and if + * FEATURE_ZLIB is disabled, filtering is disabled as + * well. + * + * If FEATURE_ZLIB is enabled and the compression type + * supported, the content is marked for decompression. + * + * XXX: Doesn't properly deal with multiple or with + * unsupported but unknown encodings. + * Is case-sensitive but shouldn't be. + * + * 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. * *********************************************************************/ -char *sed(const struct parsers pats[], - const add_header_func_ptr more_headers[], - struct client_state *csp) +static jb_err server_content_encoding(struct client_state *csp, char **header) { - struct list_entry *p; - const struct parsers *v; - const add_header_func_ptr *f; - jb_err err = JB_ERR_OK; - - for (v = pats; (err == JB_ERR_OK) && (v->str != NULL) ; v++) +#ifdef FEATURE_ZLIB + if (strstr(*header, "sdch")) { - 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; - - if (v == pats) log_error(LOG_LEVEL_HEADER, "scan: %s", p->str); + /* + * Shared Dictionary Compression over HTTP isn't supported, + * filtering it anyway is pretty much guaranteed to mess up + * the encoding. + */ + csp->content_type |= CT_TABOO; - if (strncmpic(p->str, v->str, v->len) == 0) - { - err = v->parser(csp, (char **)&(p->str)); - } + /* + * 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, + "SDCH-compressed content detected, content filtering disabled. " + "Consider suppressing SDCH offers made by the client."); } } - - /* place any additional headers on the csp->headers list */ - for (f = more_headers; (err == JB_ERR_OK) && (*f) ; f++) + else if (strstr(*header, "gzip")) { - err = (*f)(csp); + /* Mark for gzip decompression */ + csp->content_type |= CT_GZIP; } - - if (err != JB_ERR_OK) + else if (strstr(*header, "deflate")) { - return NULL; + /* 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) */ + /* + * XXX: Using a black list here isn't the right approach. + * + * In case of SDCH, building with zlib support isn't + * going to help. + */ + if (strstr(*header, "gzip") || + strstr(*header, "compress") || + strstr(*header, "deflate") || + strstr(*header, "sdch")) + { + /* + * Body is compressed, turn off pcrs and gif filtering. + */ + csp->content_type |= CT_TABOO; - return list_to_text(csp->headers); -} + /* + * 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; -/* here begins the family of parser functions that reformat header lines */ +} +#ifdef FEATURE_ZLIB /********************************************************************* * - * Function : crumble + * Function : server_adjust_content_encoding * - * Description : This is called if a header matches a pattern to "crunch" + * Description : Remove the Content-Encoding header if the + * decompression was successful and the content + * has been modifed. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -749,21 +2238,35 @@ char *sed(const struct parsers pats[], * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err crumble(struct client_state *csp, char **header) +static jb_err server_adjust_content_encoding(struct client_state *csp, char **header) { - log_error(LOG_LEVEL_HEADER, "crunch!"); - freez(*header); + 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); + } + return JB_ERR_OK; + } +#endif /* defined(FEATURE_ZLIB) */ /********************************************************************* * - * Function : server_content_type + * Function : server_adjust_content_length * - * 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 : Adjust Content-Length header if we modified + * the body. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -776,31 +2279,33 @@ jb_err crumble(struct client_state *csp, char **header) * JB_ERR_MEMORY on out-of-memory error. * *********************************************************************/ -jb_err server_content_type(struct client_state *csp, char **header) +static jb_err server_adjust_content_length(struct client_state *csp, char **header) { - if (csp->content_type != CT_TABOO) + /* Regenerate header if the content was modified. */ + if (csp->flags & CSP_FLAG_MODIFIED) { - 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; + const size_t header_length = 50; + freez(*header); + *header = malloc(header_length); + if (*header == NULL) + { + return JB_ERR_MEMORY; + } + create_content_length_header(csp->content_length, *header, header_length); + log_error(LOG_LEVEL_HEADER, + "Adjusted Content-Length to %llu", csp->content_length); } return JB_ERR_OK; } +#ifdef FEATURE_CONNECTION_KEEP_ALIVE /********************************************************************* * - * Function : server_transfer_coding + * Function : server_save_content_length * - * 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. + * Description : Save the Content-Length sent by the server. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -813,44 +2318,35 @@ 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_save_content_length(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")) + unsigned long long content_length = 0; + + assert(*(*header+14) == ':'); + + if (JB_ERR_OK != get_content_length(*header, &content_length)) { - csp->content_type = CT_TABOO; + log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header); + freez(*header); } - - /* - * Raise flag if body chunked - */ - if (strstr(*header, "chunked")) + else { - csp->flags |= CSP_FLAG_CHUNKED; - - /* - * If the body was modified, it has been - * de-chunked first, so adjust the header: - */ - if (csp->flags & CSP_FLAG_MODIFIED) - { - freez(*header); - *header = strdup("Transfer-Encoding: identity"); - return (header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; - } + csp->expected_content_length = content_length; + csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET; + csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET; } return JB_ERR_OK; } +#endif /* def FEATURE_CONNECTION_KEEP_ALIVE */ /********************************************************************* * - * Function : server_content_encoding + * Function : server_content_md5 * - * Description : Prohibit filtering (CT_TABOO) if content encoding compresses + * Description : Crumble any Content-MD5 headers if the document was + * modified. FIXME: Should we re-compute instead? * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -863,27 +2359,24 @@ 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_md5(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")) + if (csp->flags & CSP_FLAG_MODIFIED) { - csp->content_type = CT_TABOO; + log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5"); + freez(*header); } return JB_ERR_OK; - } /********************************************************************* * - * Function : server_content_length + * Function : server_content_disposition * - * Description : Adjust Content-Length header if we modified - * the body. + * Description : If enabled, blocks or modifies the "Content-Disposition" header. + * Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) @@ -896,32 +2389,56 @@ 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_content_disposition(struct client_state *csp, char **header) { - if (csp->content_length != 0) /* Content length has been modified */ + const char *newval; + + /* + * Are we messing with the Content-Disposition header? + */ + if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0) { - freez(*header); - *header = (char *) zalloc(100); - if (*header == NULL) - { - return JB_ERR_MEMORY; - } + /* Me tinks not */ + return JB_ERR_OK; + } - sprintf(*header, "Content-Length: %d", (int) csp->content_length); + newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION]; - log_error(LOG_LEVEL_HEADER, "Adjust Content-Length to %d", (int) csp->content_length); + 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); - return JB_ERR_OK; + 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_content_md5 + * Function : server_last_modified * - * Description : Crumble any Content-MD5 headers if the document was - * modified. FIXME: Should we re-compute instead? + * 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...) @@ -934,12 +2451,133 @@ 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_last_modified(struct client_state *csp, char **header) { - if (csp->flags & CSP_FLAG_MODIFIED) + const char *newval; + char buf[BUFFER_SIZE]; + time_t last_modified; + char newheader[50]; + + /* + * Are we messing with the Last-Modified header? + */ + if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0) { - log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5"); + /*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); + + 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 + { + time_t now; + struct tm *timeptr = NULL; + long int rtime; +#ifdef HAVE_GMTIME_R + struct tm gmt; +#endif + now = time(NULL); + rtime = (long int)difftime(now, last_modified); + if (rtime) + { + long int days, hours, minutes, seconds; + const int negative_delta = (rtime < 0); + + if (negative_delta) + { + rtime *= -1; + log_error(LOG_LEVEL_HEADER, "Server time in the future."); + } + rtime = pick_from_range(rtime); + if (negative_delta) + { + rtime *= -1; + } + last_modified += rtime; +#ifdef HAVE_GMTIME_R + timeptr = gmtime_r(&last_modified, &gmt); +#elif defined(MUTEX_LOCKS_AVAILABLE) + privoxy_mutex_lock(&gmtime_mutex); + timeptr = gmtime(&last_modified); + privoxy_mutex_unlock(&gmtime_mutex); +#else + timeptr = gmtime(&last_modified); +#endif + if ((NULL == timeptr) || !strftime(newheader, + sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr)) + { + log_error(LOG_LEVEL_ERROR, + "Randomizing '%s' failed. Crunching the header without replacement.", + *header); + freez(*header); + return JB_ERR_OK; + } + + 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; @@ -965,21 +2603,12 @@ 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; - } - } } return JB_ERR_OK; @@ -1004,17 +2633,18 @@ 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 @@ -1033,71 +2663,167 @@ 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_referrer(struct client_state *csp, char **header) { - const char * newval; - + 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 - * even if the request itself is non-forced, we must - * clean it unconditionally + /* + * 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 */ - /* - * Are we sending referer? - */ if ((csp->action->flags & ACTION_HIDE_REFERER) == 0) { + /* Nothing left to do */ return JB_ERR_OK; } - freez(*header); + parameter = csp->action->string[ACTION_STRING_REFERER]; + assert(parameter != NULL); + parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block")); + parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge")); + + if (!parameter_conditional_block && !parameter_conditional_forge) + { + /* + * As conditional-block and conditional-forge are the only + * parameters that rely on the original referrer, we can + * remove it now for all the others. + */ + freez(*header); + } + + if (0 == strcmpic(parameter, "block")) + { + log_error(LOG_LEVEL_HEADER, "Referer crunched!"); + return JB_ERR_OK; + } + else if (parameter_conditional_block || parameter_conditional_forge) + { + return handle_conditional_hide_referrer_parameter(header, + csp->http->hostport, parameter_conditional_block); + } + else if (0 == strcmpic(parameter, "forge")) + { + return create_forged_referrer(header, csp->http->hostport); + } + else + { + /* interpret parameter as user-supplied referer to fake */ + return create_fake_referrer(header, parameter); + } +} + + +/********************************************************************* + * + * Function : client_accept_language + * + * Description : Handle the "Accept-Language" config setting properly. + * Called from `sed'. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success, or + * JB_ERR_MEMORY on out-of-memory error. + * + *********************************************************************/ +static jb_err client_accept_language(struct client_state *csp, char **header) +{ + const char *newval; + + /* + * Are we messing with the Accept-Language? + */ + if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0) + { + /*I don't think so*/ + return JB_ERR_OK; + } - newval = csp->action->string[ACTION_STRING_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)) - { - /* - * We have a specific (fixed) referer we want to send. - */ - log_error(LOG_LEVEL_HEADER, "modified"); + else + { + /* + * Replacing Accept-Language header + */ + freez(*header); + *header = strdup("Accept-Language: "); + string_append(header, newval); + + if (*header == NULL) + { + log_error(LOG_LEVEL_ERROR, + "Insufficient memory. Accept-Language header crunched without replacement."); + } + else + { + log_error(LOG_LEVEL_HEADER, + "Accept-Language header crunched and replaced with: %s", *header); + } + } + return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; +} - *header = strdup("Referer: "); - string_append(header, newval); - return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK; - } - else +/********************************************************************* + * + * 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; } @@ -1120,9 +2846,9 @@ 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; + const char *newval; if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0) { @@ -1135,12 +2861,12 @@ 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; } @@ -1162,11 +2888,11 @@ 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); } @@ -1192,9 +2918,9 @@ 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; + const char *newval; if ((csp->action->flags & ACTION_HIDE_FROM) == 0) { @@ -1210,7 +2936,7 @@ 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; } @@ -1227,9 +2953,10 @@ 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...) @@ -1242,27 +2969,15 @@ 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) - { - /* strlen("cookie: ") == 8 */ - result = enlist(csp->cookie_list, *header + 8); - } - else + if (csp->action->flags & ACTION_NO_COOKIE_READ) { - 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; } @@ -1286,86 +3001,414 @@ 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, ": %d", &max_forwards)) + { + if (max_forwards > 0) + { + snprintf(*header, strlen(*header)+1, "Max-Forwards: %d", --max_forwards); + log_error(LOG_LEVEL_HEADER, + "Max-Forwards value for %s request reduced to %d.", + csp->http->gpc, max_forwards); + } + else if (max_forwards < 0) + { + log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header); + freez(*header); + } + } + else + { + log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header); + freez(*header); + } } return JB_ERR_OK; } -/* the following functions add headers directly to the header list */ /********************************************************************* * - * Function : client_host_adder + * Function : client_host + * + * Description : If the request URI did not contain host and + * port information, parse and evaluate the Host + * header field. * - * Description : (re)adds the host header. Called from `sed'. + * 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; + char * endptr; + + if ( 0 == strcmpic(*header, "If-Modified-Since: Wed, 08 Jun 1955 12:00:00 GMT")) { - string_append(&p, csp->http->hostport); + /* + * 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); } - - if (p == NULL) + else if (csp->action->flags & ACTION_HIDE_IF_MODIFIED_SINCE) { - return JB_ERR_MEMORY; + 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 + { + long int hours, minutes, seconds; + long int rtime = strtol(newval, &endptr, 0); + const int negative_range = (rtime < 0); + + if (rtime) + { + log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %d minut%s)", + *header, rtime, (rtime == 1 || rtime == -1) ? "e": "es"); + if (negative_range) + { + rtime *= -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_range ? -1 : 1); +#ifdef HAVE_GMTIME_R + timeptr = gmtime_r(&tm, &gmt); +#elif defined(MUTEX_LOCKS_AVAILABLE) + privoxy_mutex_lock(&gmtime_mutex); + timeptr = gmtime(&tm); + privoxy_mutex_unlock(&gmtime_mutex); +#else + timeptr = gmtime(&tm); +#endif + if ((NULL == timeptr) || !strftime(newheader, + sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr)) + { + log_error(LOG_LEVEL_ERROR, + "Randomizing '%s' failed. Crunching the header without replacement.", + *header); + freez(*header); + return JB_ERR_OK; + } + + 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_range) ? "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); } - log_error(LOG_LEVEL_HEADER, "addh: %s", p); + return JB_ERR_OK; +} + + +/********************************************************************* + * + * Function : client_x_filter + * + * Description : Disables filtering if the client set "X-Filter: No". + * Called from `sed'. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK on success + * + *********************************************************************/ +jb_err client_x_filter(struct client_state *csp, char **header) +{ + if ( 0 == strcmpic(*header, "X-Filter: No")) + { + if (!(csp->config->feature_flags & RUNTIME_FEATURE_HTTP_TOGGLE)) + { + log_error(LOG_LEVEL_INFO, "Ignored the client's request to fetch without filtering."); + } + else + { + if (csp->action->flags & ACTION_FORCE_TEXT_MODE) + { + log_error(LOG_LEVEL_HEADER, + "force-text-mode overruled the client's request to fetch without filtering!"); + } + else + { + csp->content_type = CT_TABOO; /* XXX: This hack shouldn't be necessary */ + csp->flags |= CSP_FLAG_NO_FILTERING; + log_error(LOG_LEVEL_HEADER, "Accepted the client's request to fetch without filtering."); + } + log_error(LOG_LEVEL_HEADER, "Crunching %s", *header); + freez(*header); + } + } + return JB_ERR_OK; +} - err = enlist(csp->headers, p); - freez(p); +/********************************************************************* + * + * Function : client_range + * + * Description : Removes Range, Request-Range and If-Range headers if + * content filtering is enabled. If the client's version + * of the document has been altered by Privoxy, the server + * could interpret the range differently than the client + * intended in which case the user could end up with + * corrupted content. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * 2 : header = On input, pointer to header to modify. + * On output, pointer to the modified header, or NULL + * to remove the header. This function frees the + * original string if necessary. + * + * Returns : JB_ERR_OK + * + *********************************************************************/ +static jb_err client_range(struct client_state *csp, char **header) +{ + if (content_filters_enabled(csp->action)) + { + log_error(LOG_LEVEL_HEADER, "Content filtering is enabled." + " Crunching: \'%s\' to prevent range-mismatch problems.", *header); + freez(*header); + } - return 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...) @@ -1374,61 +3417,45 @@ 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 @@ -1445,7 +3472,7 @@ 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")) ) @@ -1455,6 +3482,7 @@ jb_err client_accept_encoding_adder(struct client_state *csp) return JB_ERR_OK; } +#endif /********************************************************************* @@ -1470,7 +3498,7 @@ 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; @@ -1493,7 +3521,7 @@ 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'. * @@ -1504,48 +3532,129 @@ 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) + header = strdup("X-Forwarded-For: "); + string_append(&header, csp->ip_addr_str); + + if (header == NULL) { - p = strdup(csp->x_forwarded); - string_append(&p, ", "); + return JB_ERR_MEMORY; } - else + + log_error(LOG_LEVEL_HEADER, "addh: %s", header); + err = enlist(csp->headers, header); + freez(header); + + return err; +} + + +/********************************************************************* + * + * Function : server_connection_adder + * + * Description : Adds an appropiate "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 server_connection_adder(struct client_state *csp) +{ + const unsigned int flags = csp->flags; + const char *response_status_line = csp->headers->first->str; + static const char connection_close[] = "Connection: close"; + + if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE) + && (flags & CSP_FLAG_SERVER_CONNECTION_HEADER_SET)) { - p = strdup("X-Forwarded-For: "); + return JB_ERR_OK; } - string_append(&p, csp->ip_addr_str); - if (p == NULL) + /* + * 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) +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED) +#endif + ) { - return JB_ERR_MEMORY; + log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response " + "without Connection header implies keep-alive."); + csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE; + return JB_ERR_OK; } - log_error(LOG_LEVEL_HEADER, "addh: %s", p); - err = enlist(csp->headers, p); - free(p); + log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close); + + return enlist(csp->headers, connection_close); +} + + +#ifdef FEATURE_CONNECTION_KEEP_ALIVE +/********************************************************************* + * + * Function : server_proxy_connection_adder + * + * Description : Adds a "Proxy-Connection: keep-alive" header to + * csp->headers if the client asked for keep-alive. + * XXX: We should reuse existant ones. + * + * Parameters : + * 1 : csp = Current client state (buffers, headers, etc...) + * + * Returns : JB_ERR_OK on success, or + * JB_ERR_MEMORY on out-of-memory error. + * + *********************************************************************/ +static jb_err server_proxy_connection_adder(struct client_state *csp) +{ + static const char proxy_connection_header[] = "Proxy-Connection: keep-alive"; + jb_err err = JB_ERR_OK; + + if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE) + && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED) + && !(csp->flags & CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET)) + { + log_error(LOG_LEVEL_HEADER, "Adding: %s", proxy_connection_header); + err = enlist(csp->headers, proxy_connection_header); + } return err; } +#endif /* FEATURE_CONNECTION_KEEP_ALIVE */ /********************************************************************* * - * Function : connection_close_adder + * Function : client_connection_header_adder * - * 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! + * 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...) @@ -1554,9 +3663,29 @@ 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 client_connection_header_adder(struct client_state *csp) { - return enlist(csp->headers, "Connection: close"); + static const char connection_close[] = "Connection: close"; + + if (!(csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE) + && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET)) + { + return JB_ERR_OK; + } + +#ifdef FEATURE_CONNECTION_KEEP_ALIVE + if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE) + && (csp->http->ssl == 0) + && !strcmpic(csp->http->ver, "HTTP/1.1")) + { + csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE; + return JB_ERR_OK; + } +#endif /* FEATURE_CONNECTION_KEEP_ALIVE */ + + log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close); + + return enlist(csp->headers, connection_close); } @@ -1581,7 +3710,7 @@ 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) @@ -1591,8 +3720,21 @@ 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; @@ -1604,8 +3746,12 @@ 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'. + * 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...) @@ -1618,36 +3764,17 @@ 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) { @@ -1655,7 +3782,7 @@ jb_err server_set_cookie(struct client_state *csp, char **header) int changed = 0; /* A variable to store the tag we're working on */ - char * cur_tag; + char *cur_tag; /* Skip "Set-Cookie:" (11 characters) in header */ cur_tag = *header + 11; @@ -1670,7 +3797,7 @@ jb_err server_set_cookie(struct client_state *csp, char **header) while (*cur_tag) { /* Find next tag */ - char * next_tag = strchr(cur_tag, ';'); + char *next_tag = strchr(cur_tag, ';'); if (next_tag != NULL) { /* Skip the ';' character itself */ @@ -1688,22 +3815,100 @@ 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; + if ((expiration_date[0] == '"') + && (expiration_date[1] != '\0')) + { + /* + * Skip quotation mark. RFC 2109 10.1.2 seems to hint + * that the expiration date isn't supposed to be quoted, + * but some servers do it anyway. + */ + expiration_date++; + } + + /* 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 { @@ -1714,7 +3919,9 @@ 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); } } @@ -1737,11 +3944,14 @@ 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; @@ -1759,6 +3969,299 @@ 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; + } + + p = strdup(host); + if (NULL == p) + { + 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 hostlength = strlen(host); + const char *referer_url = NULL; + + if (NULL == referer) + { + freez(*header); + return JB_ERR_MEMORY; + } + + /* referer begins with 'Referer: http[s]://' */ + if ((hostlength+17) < strlen(referer)) + { + /* + * Shorten referer to make sure the referer is blocked + * if www.example.org/www.example.com-shall-see-the-referer/ + * links to www.example.com/ + */ + referer[hostlength+17] = '\0'; + } + referer_url = strstr(referer, "http://"); + if ((NULL == referer_url) || (NULL == strstr(referer_url, host))) + { + /* Host has changed, Referer is invalid or a https URL. */ + if (parameter_conditional_block) + { + log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header); + freez(*header); + } + else + { + freez(*header); + freez(referer); + return create_forged_referrer(header, host); + } + } + freez(referer); + + return JB_ERR_OK; + +} + + +/********************************************************************* + * + * Function : create_content_length_header + * + * Description : Creates a Content-Length header. + * + * Parameters : + * 1 : content_length = The content length to be used in the header. + * 2 : header = Allocated space to safe the header. + * 3 : buffer_length = The length of the allocated space. + * + * Returns : void + * + *********************************************************************/ +static void create_content_length_header(unsigned long long content_length, + char *header, size_t buffer_length) +{ + snprintf(header, buffer_length, "Content-Length: %llu", content_length); +} + + /* Local Variables: tab-width: 3