const char parsers_rcs[] = "$Id: parsers.c,v 1.40 2001/10/26 20:13:09 jongfoster Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/parsers.c,v $ * * Purpose : Declares functions to parse/crunch headers and pages. * Functions declared include: * `add_to_iob', `client_cookie_adder', `client_from', * `client_referrer', `client_send_cookie', `client_ua', * `client_uagent', `client_x_forwarded', * `client_x_forwarded_adder', `client_xtra_adder', * `content_type', `crumble', `destroy_list', `enlist', * `flush_socket', `free_http_request', `get_header', * `list_to_text', `parse_http_request', `sed', * and `server_set_cookie'. * * Copyright : Written by and Copyright (C) 2001 the SourceForge * IJBSWA team. http://ijbswa.sourceforge.net * * Based on the Internet Junkbuster originally written * by and Copyright (C) 1997 Anonymous Coders and * Junkbusters Corporation. http://www.junkbusters.com * * This program is free software; you can redistribute it * and/or modify it under the terms of the GNU General * Public License as published by the Free Software * Foundation; either version 2 of the License, or (at * your option) any later version. * * This program is distributed in the hope that it will * be useful, but WITHOUT ANY WARRANTY; without even the * implied warranty of MERCHANTABILITY or FITNESS FOR A * PARTICULAR PURPOSE. See the GNU General Public * License for more details. * * The GNU General Public License should be included with * this file. If not, you can view it at * http://www.gnu.org/copyleft/gpl.html * or write to the Free Software Foundation, Inc., 59 * Temple Place - Suite 330, Boston, MA 02111-1307, USA. * * Revisions : * $Log: parsers.c,v $ * Revision 1.40 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 '§' * * Revision 1.1.1.1 2001/05/15 13:59:01 oes * Initial import of version 2.9.3 source tree * * *********************************************************************/ #include "config.h" #ifndef _WIN32 #include #include #endif #include #include #include #include #if !defined(_WIN32) && !defined(__OS2__) #include #endif #include "project.h" #include "list.h" #include "parsers.h" #include "encode.h" #include "ssplit.h" #include "errlog.h" #include "jbsockets.h" #include "miscutil.h" #include "list.h" 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 * as an array index. Therefore we need to make sure that high-bit * characters generate +ve values, and ideally we also want to make * the argument match the declared parameter type of "int". * * Why did they write a character function that can't take a simple * "char" argument? Doh! */ #define ijb_isupper(__X) isupper((int)(unsigned char)(__X)) #define ijb_tolower(__X) tolower((int)(unsigned char)(__X)) const struct parsers client_patterns[] = { { "referer:", 8, client_referrer }, { "user-agent:", 11, client_uagent }, { "ua-", 3, client_ua }, { "from:", 5, client_from }, { "cookie:", 7, client_send_cookie }, { "x-forwarded-for:", 16, client_x_forwarded }, { "Accept-Encoding:", 16, client_accept_encoding }, { "TE:", 3, client_te }, { "Host:", 5, crumble }, /* { "if-modified-since:", 18, crumble }, */ { "Keep-Alive:", 11, crumble }, { "connection:", 11, crumble }, { "proxy-connection:", 17, crumble }, { 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 } }; void (* const add_client_headers[])(struct client_state *) = { client_host_adder, client_cookie_adder, client_x_forwarded_adder, client_xtra_adder, client_accept_encoding_adder, connection_close_adder, NULL }; void (* const add_server_headers[])(struct client_state *) = { connection_close_adder, NULL }; /********************************************************************* * * Function : flush_socket * * Description : Write any pending "buffered" content. * * Parameters : * 1 : fd = file descriptor of the socket to read * 2 : csp = Current client state (buffers, headers, etc...) * * Returns : On success, the number of bytes written are returned (zero * indicates nothing was written). On error, -1 is returned, * and errno is set appropriately. If count is zero and the * file descriptor refers to a regular file, 0 will be * returned without causing any other effect. For a special * file, the results are not portable. * *********************************************************************/ int flush_socket(int fd, struct client_state *csp) { struct iob *iob = csp->iob; int n = iob->eod - iob->cur; if (n <= 0) { return(0); } n = write_socket(fd, iob->cur, n); iob->eod = iob->cur = iob->buf; return(n); } /********************************************************************* * * Function : add_to_iob * * Description : Add content to the buffered page. * * 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 : Number of bytes in the content buffer. * *********************************************************************/ int add_to_iob(struct client_state *csp, char *buf, int n) { struct iob *iob = csp->iob; int have, need; char *p; have = iob->eod - iob->cur; if (n <= 0) { return(have); } need = have + n; if ((p = (char *)malloc(need + 1)) == NULL) { log_error(LOG_LEVEL_ERROR, "malloc() iob failed: %E"); return(-1); } if (have) { /* there is something in the buffer - save it */ memcpy(p, iob->cur, have); /* replace the buffer with the new space */ freez(iob->buf); iob->buf = p; /* point to the end of the data */ p += have; } else { /* the buffer is empty, free it and reinitialize */ freez(iob->buf); iob->buf = p; } /* copy the new data into the iob buffer */ memcpy(p, buf, n); /* point to the end of the data */ p += n; /* null terminate == cheap insurance */ *p = '\0'; /* set the pointers to the new values */ iob->cur = iob->buf; iob->eod = p; return(need); } /********************************************************************* * * Function : get_header * * Description : This (odd) routine will parse the csp->iob * * 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. * *********************************************************************/ char *get_header(struct client_state *csp) { struct iob *iob; char *p, *q, *ret; iob = csp->iob; if ((iob->cur == NULL) || ((p = strchr(iob->cur, '\n')) == NULL)) { return(""); /* couldn't find a complete header */ } *p = '\0'; ret = strdup(iob->cur); iob->cur = p+1; if ((q = strchr(ret, '\r'))) *q = '\0'; /* is this a blank linke (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); while (*ret && ijb_isspace(*ret)) ret++; return(ret); } } } /* * Not found */ return NULL; } /********************************************************************* * * Function : sed * * Description : add, delete or modify lines in the HTTP header streams. * On entry, it receives a linked list of headers space * that was allocated dynamically (both the list nodes * and the header contents). * * As a side effect it frees the space used by the original * header lines. * * Parameters : * 1 : pats = list of patterns to match against headers * 2 : more_headers = list of functions to add more * headers (client or server) * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : Single pointer to a fully formed header, or NULL * on out-of-memory error. * *********************************************************************/ char *sed(const struct parsers pats[], void (* const more_headers[])(struct client_state *), struct client_state *csp) { struct list_entry *p; const struct parsers *v; char *hdr; void (* const *f)(); for (v = pats; v->str ; v++) { for (p = csp->headers->first; p ; 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); if (strncmpic(p->str, v->str, v->len) == 0) { hdr = v->parser(v, p->str, csp); freez(p->str); /* FIXME: Yuck! patching a list...*/ p->str = hdr; } } } /* place any additional headers on the csp->headers list */ for (f = more_headers; *f ; f++) { (*f)(csp); } hdr = list_to_text(csp->headers); return hdr; } /********************************************************************* * * Function : free_http_request * * Description : Freez a http_request structure * * Parameters : * 1 : http = points to a http_request structure to free * * Returns : N/A * *********************************************************************/ void free_http_request(struct http_request *http) { assert(http); freez(http->cmd); freez(http->gpc); freez(http->host); freez(http->url); freez(http->hostport); freez(http->path); freez(http->ver); freez(http->host_ip_addr_str); } /********************************************************************* * * Function : parse_http_request * * Description : Parse out the host and port from the URL. Find the * hostname & path, port (if ':'), and/or password (if '@') * * Parameters : * 1 : req = URL (or is it URI?) to break down * 2 : http = pointer to the http structure to hold elements * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void parse_http_request(char *req, struct http_request *http, struct client_state *csp) { char *buf, *v[10], *url, *p; int n; memset(http, '\0', sizeof(*http)); http->cmd = strdup(req); buf = strdup(req); n = ssplit(buf, " \r\n", v, SZ(v), 1, 1); if (n == 3) { /* this could be a CONNECT request */ if (strcmpic(v[0], "connect") == 0) { http->ssl = 1; http->gpc = strdup(v[0]); http->hostport = strdup(v[1]); http->ver = strdup(v[2]); } /* or it could be any other basic HTTP request type */ if ((0 == strcmpic(v[0], "get")) || (0 == strcmpic(v[0], "head")) || (0 == strcmpic(v[0], "post")) || (0 == strcmpic(v[0], "put")) || (0 == strcmpic(v[0], "delete")) /* or a webDAV extension (RFC2518) */ || (0 == strcmpic(v[0], "propfind")) || (0 == strcmpic(v[0], "proppatch")) || (0 == strcmpic(v[0], "move")) || (0 == strcmpic(v[0], "copy")) || (0 == strcmpic(v[0], "mkcol")) || (0 == strcmpic(v[0], "lock")) || (0 == strcmpic(v[0], "unlock")) ) { http->ssl = 0; http->gpc = strdup(v[0]); http->url = strdup(v[1]); http->ver = strdup(v[2]); url = v[1]; if (strncmpic(url, "http://", 7) == 0) { url += 7; } else if (strncmpic(url, "https://", 8) == 0) { url += 8; } else { url = NULL; } if (url) { if ((p = strchr(url, '/'))) { http->path = strdup(p); *p = '\0'; http->hostport = strdup(url); } /* * Repair broken HTTP requests that don't contain a path */ else { http->path = strdup("/"); http->hostport = strdup(url); } } } } freez(buf); if (http->hostport == NULL) { free_http_request(http); return; } buf = strdup(http->hostport); /* check if url contains password */ n = ssplit(buf, "@", v, SZ(v), 1, 1); if (n == 2) { char * newbuf = NULL; newbuf = strdup(v[1]); freez(buf); buf = newbuf; } n = ssplit(buf, ":", v, SZ(v), 1, 1); if (n == 1) { http->host = strdup(v[0]); http->port = 80; } if (n == 2) { http->host = strdup(v[0]); http->port = atoi(v[1]); } freez(buf); if (http->host == NULL) { free_http_request(http); } if (http->path == NULL) { http->path = strdup("/"); } } /* here begins the family of parser functions that reformat header lines */ /********************************************************************* * * Function : crumble * * Description : This is called if a header matches a pattern to "crunch" * * Parameters : * 1 : v = Pointer to parsers structure, which basically holds * headers (client or server) that we want to "crunch" * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : Always NULL. * *********************************************************************/ char *crumble(const struct parsers *v, const char *s, struct client_state *csp) { log_error(LOG_LEVEL_HEADER, "crunch!"); return(NULL); } /********************************************************************* * * Function : server_content_type * * Description : Set the content-type for filterable types (text/.*, * javascript and image/gif) unless filtering has been * forbidden (CT_TABOO) while parsing earlier headers. * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A duplicate string pointer to this header (ie. pass thru) * *********************************************************************/ char *server_content_type(const struct parsers *v, const char *s, struct client_state *csp) { if (csp->content_type != CT_TABOO) { if (strstr(s, " text/") || strstr(s, "application/x-javascript")) csp->content_type = CT_TEXT; else if (strstr(s, " image/gif")) csp->content_type = CT_GIF; else csp->content_type = 0; } return(strdup(s)); } /********************************************************************* * * Function : server_transfer_coding * * 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. * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A duplicate string pointer to this header (ie. pass thru) * *********************************************************************/ char *server_transfer_coding(const struct parsers *v, const char *s, struct client_state *csp) { /* * Turn off pcrs and gif filtering if body compressed */ if (strstr(s, "gzip") || strstr(s, "compress") || strstr(s, "deflate")) { csp->content_type = CT_TABOO; } /* * Raise flag if body chunked */ if (strstr(s, "chunked")) { 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) { return(strdup("Transfer-Encoding: identity")); } } return(strdup(s)); } /********************************************************************* * * Function : server_content_encoding * * Description : Prohibit filtering (CT_TABOO) if content encoding compresses * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A duplicate string pointer to this header (ie. pass thru) * *********************************************************************/ char *server_content_encoding(const struct parsers *v, const char *s, struct client_state *csp) { /* * Turn off pcrs and gif filtering if body compressed */ if (strstr(s, "gzip") || strstr(s, "compress") || strstr(s, "deflate")) { csp->content_type = CT_TABOO; } return(strdup(s)); } /********************************************************************* * * Function : server_content_length * * Description : Adjust Content-Length header if we modified * the body. * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A duplicate string pointer to this header (ie. pass thru) * *********************************************************************/ char *server_content_length(const struct parsers *v, const char *s, struct client_state *csp) { if (csp->content_length != 0) /* Content length has been modified */ { char * s2 = (char *) zalloc(100); sprintf(s2, "Content-Length: %d", (int) csp->content_length); log_error(LOG_LEVEL_HEADER, "Adjust Content-Length to %d", (int) csp->content_length); return(s2); } else { return(strdup(s)); } } /********************************************************************* * * Function : server_content_md5 * * Description : Crumble any Content-MD5 headers if the document was * modified. FIXME: Should we re-compute instead? * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A duplicate string pointer to this header (ie. pass thru) * *********************************************************************/ char *server_content_md5(const struct parsers *v, const char *s, struct client_state *csp) { if (csp->flags & CSP_FLAG_MODIFIED) { log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5"); return(NULL); } else { return(strdup(s)); } } /********************************************************************* * * Function : client_accept_encoding * * Description : Rewrite the client's Accept-Encoding header so that * if doesn't allow compression, if the action applies. * Note: For HTTP/1.0 the absence of the header is enough. * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A copy of the client's original or the modified header. * *********************************************************************/ char *client_accept_encoding(const struct parsers *v, const char *s, struct client_state *csp) { if ((csp->action->flags & ACTION_NO_COMPRESSION) == 0) { return(strdup(s)); } else { log_error(LOG_LEVEL_HEADER, "Supressed offer to compress content"); if (!strcmpic(csp->http->ver, "HTTP/1.1")) { return(strdup("Accept-Encoding: identity;q=1.0, *;q=0")); } else { return(NULL); } } } /********************************************************************* * * Function : client_te * * Description : Rewrite the client's TE header so that * if doesn't allow compression, if the action applies. * * Parameters : * 1 : v = ignored * 2 : s = header string we are "considering" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A copy of the client's original or the modified header. * *********************************************************************/ char *client_te(const struct parsers *v, const char *s, struct client_state *csp) { if ((csp->action->flags & ACTION_NO_COMPRESSION) == 0) { return(strdup(s)); } else { log_error(LOG_LEVEL_HEADER, "Supressed offer to compress transfer"); return(NULL); } } /********************************************************************* * * Function : client_referrer * * Description : Handle the "referer" config setting properly. * Called from `sed'. * * Parameters : * 1 : v = ignored * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : NULL if crunched, or a malloc'ed string with the original * or modified header * *********************************************************************/ char *client_referrer(const struct parsers *v, const char *s, struct client_state *csp) { const char * newval; char * s2; #ifdef FEATURE_FORCE_LOAD /* Since the referrer can include the prefix even * even if the request itself is non-forced, we must * clean it unconditionally */ strclean(s, FORCE_PREFIX); #endif /* def FEATURE_FORCE_LOAD */ /* * Are we sending referer? */ if ((csp->action->flags & ACTION_HIDE_REFERER) == 0) { return(strdup(s)); } newval = csp->action->string[ACTION_STRING_REFERER]; /* * Are we blocking referer? */ if ((newval == NULL) || (0 == strcmpic(newval, "block")) ) { log_error(LOG_LEVEL_HEADER, "crunch!"); return(NULL); } /* * Are we forging referer? */ if (0 == strcmpic(newval, "forge")) { /* * Forge a referer as http://[hostname:port of REQUEST]/ * to fool stupid checks for in-site links */ log_error(LOG_LEVEL_HEADER, "crunch+forge!"); s2 = strsav(NULL, "Referer: "); s2 = strsav(s2, "http://"); s2 = strsav(s2, csp->http->hostport); s2 = strsav(s2, "/"); return(s2); } /* * Have we got a fixed referer? */ if (0 == strncmpic(newval, "http://", 7)) { /* * We have a specific (fixed) referer we want to send. */ char * s3; log_error(LOG_LEVEL_HEADER, "modified"); s3 = strsav( NULL, "Referer: " ); s3 = strsav( s3, newval ); return(s3); } /* Should never get here! */ log_error(LOG_LEVEL_ERROR, "Bad parameter: +referer{%s}", newval); /* * Forge is probably the best default. * * Forge a referer as http://[hostname:port of REQUEST]/ * to fool stupid checks for in-site links */ log_error(LOG_LEVEL_HEADER, "crunch+forge!"); s2 = strsav(NULL, "Referer: "); s2 = strsav(s2, "http://"); s2 = strsav(s2, csp->http->hostport); s2 = strsav(s2, "/"); return(s2); } /********************************************************************* * * Function : client_uagent * * Description : Handle the "user-agent" config setting properly * and remember its original value to enable browser * bug workarounds. Called from `sed'. * * Parameters : * 1 : v = ignored * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : A malloc'ed pointer to the default agent, or * a malloc'ed string pointer to this header (ie. pass thru). * *********************************************************************/ char *client_uagent(const struct parsers *v, const char *s, struct client_state *csp) { const char * newval; char * s2; if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0) { return(strdup(s)); } newval = csp->action->string[ACTION_STRING_USER_AGENT]; if (newval == NULL) { return(strdup(s)); } log_error(LOG_LEVEL_HEADER, "modified"); s2 = strsav( NULL, "User-Agent: " ); s2 = strsav( s2, newval ); return(s2); } /********************************************************************* * * Function : client_ua * * Description : Handle "ua-" headers properly. Called from `sed'. * * Parameters : * 1 : v = ignored * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : NULL if crunched, or a malloc'ed string to original header * *********************************************************************/ char *client_ua(const struct parsers *v, const char *s, struct client_state *csp) { if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0) { return(strdup(s)); } else { log_error(LOG_LEVEL_HEADER, "crunch!"); return(NULL); } } /********************************************************************* * * Function : client_from * * Description : Handle the "from" config setting properly. * Called from `sed'. * * Parameters : * 1 : v = ignored * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : NULL if crunched, or a malloc'ed string to * modified/original header. * *********************************************************************/ char *client_from(const struct parsers *v, const char *s, struct client_state *csp) { const char * newval; char * s2; if ((csp->action->flags & ACTION_HIDE_FROM) == 0) { return(strdup(s)); } newval = csp->action->string[ACTION_STRING_FROM]; /* * Are we blocking referer? */ if ((newval == NULL) || (0 == strcmpic(newval, "block")) ) { log_error(LOG_LEVEL_HEADER, "crunch!"); return(NULL); } log_error(LOG_LEVEL_HEADER, " modified"); s2 = strsav( NULL, "From: " ); s2 = strsav( s2, newval ); return(s2); } /********************************************************************* * * 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 ...... * * Parameters : * 1 : v = pattern of cookie `sed' found matching * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : Always NULL. * *********************************************************************/ char *client_send_cookie(const struct parsers *v, const char *s, struct client_state *csp) { if ((csp->action->flags & ACTION_NO_COOKIE_READ) == 0) { enlist(csp->cookie_list, s + v->len + 1); } else { log_error(LOG_LEVEL_HEADER, " crunch!"); } /* * Always return NULL here. The cookie header * will be sent at the end of the header. */ return(NULL); } /********************************************************************* * * Function : client_x_forwarded * * Description : Handle the "x-forwarded-for" config setting properly, * also used in the add_client_headers list. Called from `sed'. * * Parameters : * 1 : v = ignored * 2 : s = header (from sed) to "crunch" * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : Always NULL. * *********************************************************************/ char *client_x_forwarded(const struct parsers *v, const char *s, struct client_state *csp) { if ((csp->action->flags & ACTION_HIDE_FORWARDED) == 0) { /* Save it so we can re-add it later */ csp->x_forwarded = strdup(s); } /* * Always return NULL, since this information * will be sent at the end of the header. */ return(NULL); } /* the following functions add headers directly to the header list */ /********************************************************************* * * Function : client_host_adder * * Description : (re)adds the host header. Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void client_host_adder(struct client_state *csp) { char *p = NULL; p = strsav(p, "Host: "); p = strsav(p, csp->http->hostport); log_error(LOG_LEVEL_HEADER, "addh: %s", p); enlist(csp->headers, p); freez(p); } /********************************************************************* * * Function : client_cookie_adder * * Description : Used in the add_client_headers list. Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void client_cookie_adder(struct client_state *csp) { struct list_entry *lst; char *tmp = NULL; char *e; for (lst = csp->cookie_list->first; lst ; lst = lst->next) { if (tmp) { tmp = strsav(tmp, "; "); } tmp = strsav(tmp, lst->str); } for (lst = csp->action->multi[ACTION_MULTI_WAFER]->first; lst ; lst = lst->next) { if (tmp) { tmp = strsav(tmp, "; "); } if ((e = cookie_encode(lst->str))) { tmp = strsav(tmp, e); freez(e); } } if (tmp) { char *ret; ret = strdup("Cookie: "); ret = strsav(ret, tmp); log_error(LOG_LEVEL_HEADER, "addh: %s", ret); enlist(csp->headers, ret); freez(tmp); freez(ret); } } /********************************************************************* * * Function : client_accept_encoding_adder * * Description : Add an Accept-Encoding header to the client's request * that disables compression if the action applies, and * the header is not already there. Called from `sed'. * Note: For HTTP/1.0, the absence of the header is enough. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void client_accept_encoding_adder(struct client_state *csp) { if ( ((csp->action->flags & ACTION_NO_COMPRESSION) != 0) && (!strcmpic(csp->http->ver, "HTTP/1.1")) ) { enlist_unique(csp->headers, "Accept-Encoding: identity;q=1.0, *;q=0", 16); } } /********************************************************************* * * Function : client_xtra_adder * * Description : Used in the add_client_headers list. Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void client_xtra_adder(struct client_state *csp) { struct list_entry *lst; for (lst = csp->action->multi[ACTION_MULTI_ADD_HEADER]->first; lst ; lst = lst->next) { log_error(LOG_LEVEL_HEADER, "addh: %s", lst->str); enlist(csp->headers, lst->str); } } /********************************************************************* * * Function : client_x_forwarded_adder * * Description : Used in the add_client_headers list. Called from `sed'. * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void client_x_forwarded_adder(struct client_state *csp) { char *p = NULL; if ((csp->action->flags & ACTION_HIDE_FORWARDED) != 0) { return; } if (csp->x_forwarded) { p = strsav(p, csp->x_forwarded); p = strsav(p, ", "); p = strsav(p, csp->ip_addr_str); } else { p = strsav(p, "X-Forwarded-For: "); p = strsav(p, csp->ip_addr_str); } log_error(LOG_LEVEL_HEADER, "addh: %s", p); enlist(csp->headers, p); freez(p); } /********************************************************************* * * Function : connection_close_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! * * Parameters : * 1 : csp = Current client state (buffers, headers, etc...) * * Returns : N/A * *********************************************************************/ void connection_close_adder(struct client_state *csp) { enlist(csp->headers, "Connection: close"); } /********************************************************************* * * Function : server_http * * Description : - Save the HTTP Status into csp->http->status * - Set CT_TABOO to prevent filtering if the answer * is a partial range (HTTP status 206) * - Rewrite HTTP/1.1 answers to HTTP/1.0 if +downgrade * action applies. * * Parameters : * 1 : v = parser pattern that matched this header * 2 : s = header that matched this pattern * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : Copy of changed or original answer. * *********************************************************************/ char *server_http(const struct parsers *v, const char *s, struct client_state *csp) { char *ret = strdup(s); sscanf(ret, "HTTP/%*d.%*d %d", &(csp->http->status)); if (csp->http->status == 206) { csp->content_type = CT_TABOO; } if ((csp->action->flags & ACTION_DOWNGRADE) != 0) { ret[7] = '0'; log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0"); } return(ret); } /********************************************************************* * * 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'. * * Parameters : * 1 : v = parser pattern that matched this header * 2 : s = header that matched this pattern * 3 : csp = Current client state (buffers, headers, etc...) * * Returns : `crumble' or a newly malloc'ed string. * *********************************************************************/ char *server_set_cookie(const struct parsers *v, const char *s, struct client_state *csp) { #ifdef FEATURE_COOKIE_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); tm_now = localtime (&now); strftime (tempbuf, BUFFER_SIZE-6, "%b %d %H:%M:%S ", tm_now); if (csp->config->jar) { fprintf(csp->config->jar, "%s %s\t%s\n", tempbuf, csp->http->host, (s + v->len + 1)); } #endif /* def FEATURE_COOKIE_JAR */ if ((csp->action->flags & ACTION_NO_COOKIE_SET) != 0) { return(crumble(v, s, csp)); } return(strdup(s)); } #ifdef FEATURE_FORCE_LOAD /********************************************************************* * * Function : strclean * * Description : In-Situ-Eliminate all occurances of substring in * string * * Parameters : * 1 : string = string to clean * 2 : substring = substring to eliminate * * Returns : Number of eliminations * *********************************************************************/ int strclean(const char *string, const char *substring) { int hits = 0, len = strlen(substring); char *pos, *p; while((pos = strstr(string, substring))) { p = pos + len; do { *(p - len) = *p; } while (*p++ != '\0'); hits++; } return(hits); } #endif /* def FEATURE_FORCE_LOAD */ /* Local Variables: tab-width: 3 end: */