1 const char parsers_rcs[] = "$Id: parsers.c,v 1.196 2009/07/11 11:20:12 fabiankeil Exp $";
2 /*********************************************************************
4 * File : $Source: /cvsroot/ijbswa/current/parsers.c,v $
6 * Purpose : Declares functions to parse/crunch headers and pages.
7 * Functions declared include:
8 * `add_to_iob', `client_cookie_adder', `client_from',
9 * `client_referrer', `client_send_cookie', `client_ua',
10 * `client_uagent', `client_x_forwarded',
11 * `client_x_forwarded_adder', `client_xtra_adder',
12 * `content_type', `crumble', `destroy_list', `enlist',
13 * `flush_socket', ``get_header', `sed', `filter_header'
14 * `server_content_encoding', `server_content_disposition',
15 * `server_last_modified', `client_accept_language',
16 * `crunch_client_header', `client_if_modified_since',
17 * `client_if_none_match', `get_destination_from_headers',
18 * `parse_header_time', `decompress_iob' and `server_set_cookie'.
20 * Copyright : Written by and Copyright (C) 2001-2009 the
21 * Privoxy team. http://www.privoxy.org/
23 * Based on the Internet Junkbuster originally written
24 * by and Copyright (C) 1997 Anonymous Coders and
25 * Junkbusters Corporation. http://www.junkbusters.com
27 * This program is free software; you can redistribute it
28 * and/or modify it under the terms of the GNU General
29 * Public License as published by the Free Software
30 * Foundation; either version 2 of the License, or (at
31 * your option) any later version.
33 * This program is distributed in the hope that it will
34 * be useful, but WITHOUT ANY WARRANTY; without even the
35 * implied warranty of MERCHANTABILITY or FITNESS FOR A
36 * PARTICULAR PURPOSE. See the GNU General Public
37 * License for more details.
39 * The GNU General Public License should be included with
40 * this file. If not, you can view it at
41 * http://www.gnu.org/copyleft/gpl.html
42 * or write to the Free Software Foundation, Inc., 59
43 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
45 *********************************************************************/
52 #include <sys/types.h>
62 * Convince GNU's libc to provide a strptime prototype.
71 #define GZIP_IDENTIFIER_1 0x1f
72 #define GZIP_IDENTIFIER_2 0x8b
74 #define GZIP_FLAG_CHECKSUM 0x02
75 #define GZIP_FLAG_EXTRA_FIELDS 0x04
76 #define GZIP_FLAG_FILE_NAME 0x08
77 #define GZIP_FLAG_COMMENT 0x10
78 #define GZIP_FLAG_RESERVED_BITS 0xe0
81 #if !defined(_WIN32) && !defined(__OS2__)
87 #ifdef FEATURE_PTHREAD
89 /* jcc.h is for mutex semapores only */
90 #endif /* def FEATURE_PTHREAD */
95 #include "jbsockets.h"
101 #ifndef HAVE_STRPTIME
102 #include "strptime.h"
105 const char parsers_h_rcs[] = PARSERS_H_VERSION;
107 /* Fix a problem with Solaris. There should be no effect on other
109 * Solaris's isspace() is a macro which uses its argument directly
110 * as an array index. Therefore we need to make sure that high-bit
111 * characters generate +ve values, and ideally we also want to make
112 * the argument match the declared parameter type of "int".
114 * Why did they write a character function that can't take a simple
115 * "char" argument? Doh!
117 #define ijb_isupper(__X) isupper((int)(unsigned char)(__X))
118 #define ijb_tolower(__X) tolower((int)(unsigned char)(__X))
120 static char *get_header_line(struct iob *iob);
121 static jb_err scan_headers(struct client_state *csp);
122 static jb_err header_tagger(struct client_state *csp, char *header);
123 static jb_err parse_header_time(const char *header_time, time_t *result);
125 static jb_err crumble (struct client_state *csp, char **header);
126 static jb_err filter_header (struct client_state *csp, char **header);
127 static jb_err client_connection (struct client_state *csp, char **header);
128 static jb_err client_referrer (struct client_state *csp, char **header);
129 static jb_err client_uagent (struct client_state *csp, char **header);
130 static jb_err client_ua (struct client_state *csp, char **header);
131 static jb_err client_from (struct client_state *csp, char **header);
132 static jb_err client_send_cookie (struct client_state *csp, char **header);
133 static jb_err client_x_forwarded (struct client_state *csp, char **header);
134 static jb_err client_accept_encoding (struct client_state *csp, char **header);
135 static jb_err client_te (struct client_state *csp, char **header);
136 static jb_err client_max_forwards (struct client_state *csp, char **header);
137 static jb_err client_host (struct client_state *csp, char **header);
138 static jb_err client_if_modified_since (struct client_state *csp, char **header);
139 static jb_err client_accept_language (struct client_state *csp, char **header);
140 static jb_err client_if_none_match (struct client_state *csp, char **header);
141 static jb_err crunch_client_header (struct client_state *csp, char **header);
142 static jb_err client_x_filter (struct client_state *csp, char **header);
143 static jb_err client_range (struct client_state *csp, char **header);
144 static jb_err server_set_cookie (struct client_state *csp, char **header);
145 static jb_err server_connection (struct client_state *csp, char **header);
146 static jb_err server_content_type (struct client_state *csp, char **header);
147 static jb_err server_adjust_content_length(struct client_state *csp, char **header);
148 static jb_err server_content_md5 (struct client_state *csp, char **header);
149 static jb_err server_content_encoding (struct client_state *csp, char **header);
150 static jb_err server_transfer_coding (struct client_state *csp, char **header);
151 static jb_err server_http (struct client_state *csp, char **header);
152 static jb_err crunch_server_header (struct client_state *csp, char **header);
153 static jb_err server_last_modified (struct client_state *csp, char **header);
154 static jb_err server_content_disposition(struct client_state *csp, char **header);
156 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
157 static jb_err server_save_content_length(struct client_state *csp, char **header);
158 static jb_err server_keep_alive(struct client_state *csp, char **header);
159 static jb_err client_keep_alive(struct client_state *csp, char **header);
160 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
162 static jb_err client_host_adder (struct client_state *csp);
163 static jb_err client_xtra_adder (struct client_state *csp);
164 static jb_err client_x_forwarded_for_adder(struct client_state *csp);
165 static jb_err client_connection_header_adder(struct client_state *csp);
166 static jb_err server_connection_adder(struct client_state *csp);
167 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
168 static jb_err server_proxy_connection_adder(struct client_state *csp);
169 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
171 static jb_err create_forged_referrer(char **header, const char *hostport);
172 static jb_err create_fake_referrer(char **header, const char *fake_referrer);
173 static jb_err handle_conditional_hide_referrer_parameter(char **header,
174 const char *host, const int parameter_conditional_block);
175 static void create_content_length_header(unsigned long long content_length,
176 char *header, size_t buffer_length);
179 * List of functions to run on a list of headers.
183 /** The header prefix to match */
186 /** The length of the prefix to match */
189 /** The function to apply to this line */
190 const parser_func_ptr parser;
193 static const struct parsers client_patterns[] = {
194 { "referer:", 8, client_referrer },
195 { "user-agent:", 11, client_uagent },
196 { "ua-", 3, client_ua },
197 { "from:", 5, client_from },
198 { "cookie:", 7, client_send_cookie },
199 { "x-forwarded-for:", 16, client_x_forwarded },
200 { "Accept-Encoding:", 16, client_accept_encoding },
201 { "TE:", 3, client_te },
202 { "Host:", 5, client_host },
203 { "if-modified-since:", 18, client_if_modified_since },
204 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
205 { "Keep-Alive:", 11, client_keep_alive },
207 { "Keep-Alive:", 11, crumble },
209 { "connection:", 11, client_connection },
210 { "proxy-connection:", 17, crumble },
211 { "max-forwards:", 13, client_max_forwards },
212 { "Accept-Language:", 16, client_accept_language },
213 { "if-none-match:", 14, client_if_none_match },
214 { "Range:", 6, client_range },
215 { "Request-Range:", 14, client_range },
216 { "If-Range:", 9, client_range },
217 { "X-Filter:", 9, client_x_filter },
218 { "*", 0, crunch_client_header },
219 { "*", 0, filter_header },
223 static const struct parsers server_patterns[] = {
224 { "HTTP/", 5, server_http },
225 { "set-cookie:", 11, server_set_cookie },
226 { "connection:", 11, server_connection },
227 { "Content-Type:", 13, server_content_type },
228 { "Content-MD5:", 12, server_content_md5 },
229 { "Content-Encoding:", 17, server_content_encoding },
230 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
231 { "Content-Length:", 15, server_save_content_length },
232 { "Keep-Alive:", 11, server_keep_alive },
234 { "Keep-Alive:", 11, crumble },
235 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
236 { "Transfer-Encoding:", 18, server_transfer_coding },
237 { "content-disposition:", 20, server_content_disposition },
238 { "Last-Modified:", 14, server_last_modified },
239 { "*", 0, crunch_server_header },
240 { "*", 0, filter_header },
244 static const add_header_func_ptr add_client_headers[] = {
246 client_x_forwarded_for_adder,
248 /* Temporarily disabled: client_accept_encoding_adder, */
249 client_connection_header_adder,
253 static const add_header_func_ptr add_server_headers[] = {
254 server_connection_adder,
255 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
256 server_proxy_connection_adder,
257 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
261 /*********************************************************************
263 * Function : flush_socket
265 * Description : Write any pending "buffered" content.
268 * 1 : fd = file descriptor of the socket to read
269 * 2 : iob = The I/O buffer to flush, usually csp->iob.
271 * Returns : On success, the number of bytes written are returned (zero
272 * indicates nothing was written). On error, -1 is returned,
273 * and errno is set appropriately. If count is zero and the
274 * file descriptor refers to a regular file, 0 will be
275 * returned without causing any other effect. For a special
276 * file, the results are not portable.
278 *********************************************************************/
279 long flush_socket(jb_socket fd, struct iob *iob)
281 long len = iob->eod - iob->cur;
288 if (write_socket(fd, iob->cur, (size_t)len))
292 iob->eod = iob->cur = iob->buf;
298 /*********************************************************************
300 * Function : add_to_iob
302 * Description : Add content to the buffered page, expanding the
303 * buffer if necessary.
306 * 1 : csp = Current client state (buffers, headers, etc...)
307 * 2 : buf = holds the content to be added to the page
308 * 3 : n = number of bytes to be added
310 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY if out-of-memory
311 * or buffer limit reached.
313 *********************************************************************/
314 jb_err add_to_iob(struct client_state *csp, char *buf, long n)
316 struct iob *iob = csp->iob;
317 size_t used, offset, need, want;
320 if (n <= 0) return JB_ERR_OK;
322 used = (size_t)(iob->eod - iob->buf);
323 offset = (size_t)(iob->cur - iob->buf);
324 need = used + (size_t)n + 1;
327 * If the buffer can't hold the new data, extend it first.
328 * Use the next power of two if possible, else use the actual need.
330 if (need > csp->config->buffer_limit)
332 log_error(LOG_LEVEL_INFO,
333 "Buffer limit reached while extending the buffer (iob). Needed: %d. Limit: %d",
334 need, csp->config->buffer_limit);
335 return JB_ERR_MEMORY;
338 if (need > iob->size)
340 for (want = csp->iob->size ? csp->iob->size : 512; want <= need;) want *= 2;
342 if (want <= csp->config->buffer_limit && NULL != (p = (char *)realloc(iob->buf, want)))
346 else if (NULL != (p = (char *)realloc(iob->buf, need)))
352 log_error(LOG_LEVEL_ERROR, "Extending the buffer (iob) failed: %E");
353 return JB_ERR_MEMORY;
356 /* Update the iob pointers */
357 iob->cur = p + offset;
362 /* copy the new data into the iob buffer */
363 memcpy(iob->eod, buf, (size_t)n);
365 /* point to the end of the data */
368 /* null terminate == cheap insurance */
377 /*********************************************************************
379 * Function : decompress_iob
381 * Description : Decompress buffered page, expanding the
382 * buffer as necessary. csp->iob->cur
383 * should point to the the beginning of the
384 * compressed data block.
387 * 1 : csp = Current client state (buffers, headers, etc...)
389 * Returns : JB_ERR_OK on success,
390 * JB_ERR_MEMORY if out-of-memory limit reached, and
391 * JB_ERR_COMPRESS if error decompressing buffer.
393 *********************************************************************/
394 jb_err decompress_iob(struct client_state *csp)
396 char *buf; /* new, uncompressed buffer */
397 char *cur; /* Current iob position (to keep the original
398 * iob->cur unmodified if we return early) */
399 size_t bufsize; /* allocated size of the new buffer */
400 size_t old_size; /* Content size before decompression */
401 size_t skip_size; /* Number of bytes at the beginning of the iob
402 that we should NOT decompress. */
403 int status; /* return status of the inflate() call */
404 z_stream zstr; /* used by calls to zlib */
406 assert(csp->iob->cur - csp->iob->buf > 0);
407 assert(csp->iob->eod - csp->iob->cur > 0);
409 bufsize = csp->iob->size;
410 skip_size = (size_t)(csp->iob->cur - csp->iob->buf);
411 old_size = (size_t)(csp->iob->eod - csp->iob->cur);
415 if (bufsize < (size_t)10)
418 * This is to protect the parsing of gzipped data,
419 * but it should(?) be valid for deflated data also.
421 log_error(LOG_LEVEL_ERROR, "Buffer too small decompressing iob");
422 return JB_ERR_COMPRESS;
425 if (csp->content_type & CT_GZIP)
428 * Our task is slightly complicated by the facts that data
429 * compressed by gzip does not include a zlib header, and
430 * that there is no easily accessible interface in zlib to
431 * handle a gzip header. We strip off the gzip header by
432 * hand, and later inform zlib not to expect a header.
436 * Strip off the gzip header. Please see RFC 1952 for more
437 * explanation of the appropriate fields.
439 if (((*cur++ & 0xff) != GZIP_IDENTIFIER_1)
440 || ((*cur++ & 0xff) != GZIP_IDENTIFIER_2)
441 || (*cur++ != Z_DEFLATED))
443 log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
444 return JB_ERR_COMPRESS;
449 if (flags & GZIP_FLAG_RESERVED_BITS)
451 /* The gzip header has reserved bits set; bail out. */
452 log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
453 return JB_ERR_COMPRESS;
457 * Skip mtime (4 bytes), extra flags (1 byte)
458 * and OS type (1 byte).
462 /* Skip extra fields if necessary. */
463 if (flags & GZIP_FLAG_EXTRA_FIELDS)
466 * Skip a given number of bytes, specified
467 * as a 16-bit little-endian value.
469 * XXX: this code is untested and should probably be removed.
473 skip_bytes += *cur++ << 8;
476 * The number of bytes to skip should be positive
477 * and we'd like to stay in the buffer.
479 if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
481 log_error(LOG_LEVEL_ERROR,
482 "Unreasonable amount of bytes to skip (%d). Stopping decompression",
484 return JB_ERR_COMPRESS;
486 log_error(LOG_LEVEL_INFO,
487 "Skipping %d bytes for gzip compression. Does this sound right?",
492 /* Skip the filename if necessary. */
493 if (flags & GZIP_FLAG_FILE_NAME)
495 /* A null-terminated string is supposed to follow. */
496 while (*cur++ && (cur < csp->iob->eod));
499 /* Skip the comment if necessary. */
500 if (flags & GZIP_FLAG_COMMENT)
502 /* A null-terminated string is supposed to follow. */
503 while (*cur++ && (cur < csp->iob->eod));
506 /* Skip the CRC if necessary. */
507 if (flags & GZIP_FLAG_CHECKSUM)
512 if (cur >= csp->iob->eod)
515 * If the current position pointer reached or passed
516 * the buffer end, we were obviously tricked to skip
519 log_error(LOG_LEVEL_ERROR,
520 "Malformed gzip header detected. Aborting decompression.");
521 return JB_ERR_COMPRESS;
525 else if (csp->content_type & CT_DEFLATE)
528 * XXX: The debug level should be lowered
529 * before the next stable release.
531 log_error(LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur);
533 * In theory (that is, according to RFC 1950), deflate-compressed
534 * data should begin with a two-byte zlib header and have an
535 * adler32 checksum at the end. It seems that in practice only
536 * the raw compressed data is sent. Note that this means that
537 * we are not RFC 1950-compliant here, but the advantage is that
538 * this actually works. :)
540 * We add a dummy null byte to tell zlib where the data ends,
541 * and later inform it not to expect a header.
543 * Fortunately, add_to_iob() has thoughtfully null-terminated
544 * the buffer; we can just increment the end pointer to include
551 log_error(LOG_LEVEL_ERROR,
552 "Unable to determine compression format for decompression");
553 return JB_ERR_COMPRESS;
556 /* Set up the fields required by zlib. */
557 zstr.next_in = (Bytef *)cur;
558 zstr.avail_in = (unsigned int)(csp->iob->eod - cur);
559 zstr.zalloc = Z_NULL;
561 zstr.opaque = Z_NULL;
564 * Passing -MAX_WBITS to inflateInit2 tells the library
565 * that there is no zlib header.
567 if (inflateInit2(&zstr, -MAX_WBITS) != Z_OK)
569 log_error(LOG_LEVEL_ERROR, "Error initializing decompression");
570 return JB_ERR_COMPRESS;
574 * Next, we allocate new storage for the inflated data.
575 * We don't modify the existing iob yet, so in case there
576 * is error in decompression we can recover gracefully.
578 buf = zalloc(bufsize);
581 log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
582 return JB_ERR_MEMORY;
585 assert(bufsize >= skip_size);
586 memcpy(buf, csp->iob->buf, skip_size);
587 zstr.avail_out = bufsize - skip_size;
588 zstr.next_out = (Bytef *)buf + skip_size;
590 /* Try to decompress the whole stream in one shot. */
591 while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH)))
593 /* We need to allocate more memory for the output buffer. */
595 char *tmpbuf; /* used for realloc'ing the buffer */
596 size_t oldbufsize = bufsize; /* keep track of the old bufsize */
598 if (0 == zstr.avail_in)
601 * If zlib wants more data then there's a problem, because
602 * the complete compressed file should have been buffered.
604 log_error(LOG_LEVEL_ERROR,
605 "Unexpected end of compressed iob. Using what we got so far.");
610 * If we tried the limit and still didn't have enough
611 * memory, just give up.
613 if (bufsize == csp->config->buffer_limit)
615 log_error(LOG_LEVEL_ERROR, "Buffer limit reached while decompressing iob");
616 return JB_ERR_MEMORY;
619 /* Try doubling the buffer size each time. */
622 /* Don't exceed the buffer limit. */
623 if (bufsize > csp->config->buffer_limit)
625 bufsize = csp->config->buffer_limit;
628 /* Try to allocate the new buffer. */
629 tmpbuf = realloc(buf, bufsize);
632 log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
634 return JB_ERR_MEMORY;
638 char *oldnext_out = (char *)zstr.next_out;
641 * Update the fields for inflate() to use the new
642 * buffer, which may be in a location different from
645 zstr.avail_out += bufsize - oldbufsize;
646 zstr.next_out = (Bytef *)tmpbuf + bufsize - zstr.avail_out;
649 * Compare with an uglier method of calculating these values
650 * that doesn't require the extra oldbufsize variable.
652 assert(zstr.avail_out == tmpbuf + bufsize - (char *)zstr.next_out);
653 assert((char *)zstr.next_out == tmpbuf + ((char *)oldnext_out - buf));
654 assert(zstr.avail_out > 0U);
660 if (Z_STREAM_ERROR == inflateEnd(&zstr))
662 log_error(LOG_LEVEL_ERROR,
663 "Inconsistent stream state after decompression: %s", zstr.msg);
665 * XXX: Intentionally no return.
667 * According to zlib.h, Z_STREAM_ERROR is returned
668 * "if the stream state was inconsistent".
670 * I assume in this case inflate()'s status
671 * would also be something different than Z_STREAM_END
672 * so this check should be redundant, but lets see.
676 if ((status != Z_STREAM_END) && (0 != zstr.avail_in))
679 * We failed to decompress the stream and it's
680 * not simply because of missing data.
682 log_error(LOG_LEVEL_ERROR,
683 "Unexpected error while decompressing to the buffer (iob): %s",
685 return JB_ERR_COMPRESS;
689 * Finally, we can actually update the iob, since the
690 * decompression was successful. First, free the old
693 freez(csp->iob->buf);
695 /* Now, update the iob to use the new buffer. */
697 csp->iob->cur = csp->iob->buf + skip_size;
698 csp->iob->eod = (char *)zstr.next_out;
699 csp->iob->size = bufsize;
702 * Make sure the new uncompressed iob obeys some minimal
703 * consistency conditions.
705 if ((csp->iob->buf < csp->iob->cur)
706 && (csp->iob->cur <= csp->iob->eod)
707 && (csp->iob->eod <= csp->iob->buf + csp->iob->size))
709 const size_t new_size = (size_t)(csp->iob->eod - csp->iob->cur);
710 if (new_size > (size_t)0)
712 log_error(LOG_LEVEL_RE_FILTER,
713 "Decompression successful. Old size: %d, new size: %d.",
718 /* zlib thinks this is OK, so lets do the same. */
719 log_error(LOG_LEVEL_INFO, "Decompression didn't result in any content.");
724 /* It seems that zlib did something weird. */
725 log_error(LOG_LEVEL_ERROR,
726 "Unexpected error decompressing the buffer (iob): %d==%d, %d>%d, %d<%d",
727 csp->iob->cur, csp->iob->buf + skip_size, csp->iob->eod, csp->iob->buf,
728 csp->iob->eod, csp->iob->buf + csp->iob->size);
729 return JB_ERR_COMPRESS;
735 #endif /* defined(FEATURE_ZLIB) */
738 /*********************************************************************
740 * Function : string_move
742 * Description : memmove wrapper to move the last part of a string
743 * towards the beginning, overwriting the part in
744 * the middle. strlcpy() can't be used here as the
748 * 1 : dst = Destination to overwrite
749 * 2 : src = Source to move.
753 *********************************************************************/
754 static void string_move(char *dst, char *src)
758 /* +1 to copy the terminating nul as well. */
759 memmove(dst, src, strlen(src)+1);
763 /*********************************************************************
765 * Function : normalize_lws
767 * Description : Reduces unquoted linear white space in headers
768 * to a single space in accordance with RFC 2616 2.2.
769 * This simplifies parsing and filtering later on.
771 * XXX: Remove log messages before
772 * the next stable release?
775 * 1 : header = A header with linear white space to reduce.
779 *********************************************************************/
780 static void normalize_lws(char *header)
786 if (ijb_isspace(*p) && ijb_isspace(*(p+1)))
790 while (ijb_isspace(*q))
794 log_error(LOG_LEVEL_HEADER, "Reducing white space in '%s'", header);
800 log_error(LOG_LEVEL_HEADER,
801 "Converting tab to space in '%s'", header);
806 char *end_of_token = strstr(p+1, "\"");
808 if (NULL != end_of_token)
810 /* Don't mess with quoted text. */
815 log_error(LOG_LEVEL_HEADER,
816 "Ignoring single quote in '%s'", header);
822 p = strchr(header, ':');
823 if ((p != NULL) && (p != header) && ijb_isspace(*(p-1)))
826 * There's still space before the colon.
834 /*********************************************************************
836 * Function : get_header
838 * Description : This (odd) routine will parse the csp->iob
839 * to get the next complete header.
842 * 1 : iob = The I/O buffer to parse, usually csp->iob.
844 * Returns : Any one of the following:
846 * 1) a pointer to a dynamically allocated string that contains a header line
847 * 2) NULL indicating that the end of the header was reached
848 * 3) "" indicating that the end of the iob was reached before finding
849 * a complete header line.
851 *********************************************************************/
852 char *get_header(struct iob *iob)
856 header = get_header_line(iob);
858 if ((header == NULL) || (*header == '\0'))
861 * No complete header read yet, tell the client.
866 while ((iob->cur[0] == ' ') || (iob->cur[0] == '\t'))
869 * Header spans multiple lines, append the next one.
871 char *continued_header;
873 continued_header = get_header_line(iob);
874 if ((continued_header == NULL) || (*continued_header == '\0'))
877 * No complete header read yet, return what we got.
878 * XXX: Should "unread" header instead.
880 log_error(LOG_LEVEL_INFO,
881 "Failed to read a multi-line header properly: '%s'",
886 if (JB_ERR_OK != string_join(&header, continued_header))
888 log_error(LOG_LEVEL_FATAL,
889 "Out of memory while appending multiple headers.");
893 /* XXX: remove before next stable release. */
894 log_error(LOG_LEVEL_HEADER,
895 "Merged multiple header lines to: '%s'",
900 normalize_lws(header);
907 /*********************************************************************
909 * Function : get_header_line
911 * Description : This (odd) routine will parse the csp->iob
912 * to get the next header line.
915 * 1 : iob = The I/O buffer to parse, usually csp->iob.
917 * Returns : Any one of the following:
919 * 1) a pointer to a dynamically allocated string that contains a header line
920 * 2) NULL indicating that the end of the header was reached
921 * 3) "" indicating that the end of the iob was reached before finding
922 * a complete header line.
924 *********************************************************************/
925 static char *get_header_line(struct iob *iob)
929 if ((iob->cur == NULL)
930 || ((p = strchr(iob->cur, '\n')) == NULL))
932 return(""); /* couldn't find a complete header */
937 ret = strdup(iob->cur);
940 /* FIXME No way to handle error properly */
941 log_error(LOG_LEVEL_FATAL, "Out of memory in get_header_line()");
947 if ((q = strchr(ret, '\r')) != NULL) *q = '\0';
949 /* is this a blank line (i.e. the end of the header) ? */
961 /*********************************************************************
963 * Function : get_header_value
965 * Description : Get the value of a given header from a chained list
966 * of header lines or return NULL if no such header is
967 * present in the list.
970 * 1 : header_list = pointer to list
971 * 2 : header_name = string with name of header to look for.
972 * Trailing colon required, capitalization
975 * Returns : NULL if not found, else value of header
977 *********************************************************************/
978 char *get_header_value(const struct list *header_list, const char *header_name)
980 struct list_entry *cur_entry;
986 length = strlen(header_name);
988 for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next)
992 if (!strncmpic(cur_entry->str, header_name, length))
995 * Found: return pointer to start of value
997 ret = cur_entry->str + length;
998 while (*ret && ijb_isspace(*ret)) ret++;
1012 /*********************************************************************
1014 * Function : scan_headers
1016 * Description : Scans headers, applies tags and updates action bits.
1019 * 1 : csp = Current client state (buffers, headers, etc...)
1021 * Returns : JB_ERR_OK
1023 *********************************************************************/
1024 static jb_err scan_headers(struct client_state *csp)
1026 struct list_entry *h; /* Header */
1027 jb_err err = JB_ERR_OK;
1029 for (h = csp->headers->first; (err == JB_ERR_OK) && (h != NULL) ; h = h->next)
1031 /* Header crunch()ed in previous run? -> ignore */
1032 if (h->str == NULL) continue;
1033 log_error(LOG_LEVEL_HEADER, "scan: %s", h->str);
1034 err = header_tagger(csp, h->str);
1041 /*********************************************************************
1045 * Description : add, delete or modify lines in the HTTP header streams.
1046 * On entry, it receives a linked list of headers space
1047 * that was allocated dynamically (both the list nodes
1048 * and the header contents).
1050 * As a side effect it frees the space used by the original
1054 * 1 : csp = Current client state (buffers, headers, etc...)
1055 * 2 : filter_server_headers = Boolean to switch between
1056 * server and header filtering.
1058 * Returns : JB_ERR_OK in case off success, or
1059 * JB_ERR_MEMORY on out-of-memory error.
1061 *********************************************************************/
1062 jb_err sed(struct client_state *csp, int filter_server_headers)
1064 /* XXX: use more descriptive names. */
1065 struct list_entry *p;
1066 const struct parsers *v;
1067 const add_header_func_ptr *f;
1068 jb_err err = JB_ERR_OK;
1070 if (filter_server_headers)
1072 v = server_patterns;
1073 f = add_server_headers;
1077 v = client_patterns;
1078 f = add_client_headers;
1083 while ((err == JB_ERR_OK) && (v->str != NULL))
1085 for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
1087 /* Header crunch()ed in previous run? -> ignore */
1088 if (p->str == NULL) continue;
1090 /* Does the current parser handle this header? */
1091 if ((strncmpic(p->str, v->str, v->len) == 0) ||
1092 (v->len == CHECK_EVERY_HEADER_REMAINING))
1094 err = v->parser(csp, &(p->str));
1100 /* place additional headers on the csp->headers list */
1101 while ((err == JB_ERR_OK) && (*f))
1111 /*********************************************************************
1113 * Function : update_server_headers
1115 * Description : Updates server headers after the body has been modified.
1118 * 1 : csp = Current client state (buffers, headers, etc...)
1120 * Returns : JB_ERR_OK in case off success, or
1121 * JB_ERR_MEMORY on out-of-memory error.
1123 *********************************************************************/
1124 jb_err update_server_headers(struct client_state *csp)
1126 jb_err err = JB_ERR_OK;
1128 static const struct parsers server_patterns_light[] = {
1129 { "Content-Length:", 15, server_adjust_content_length },
1130 { "Transfer-Encoding:", 18, server_transfer_coding },
1132 { "Content-Encoding:", 17, server_content_encoding },
1133 #endif /* def FEATURE_ZLIB */
1137 if (strncmpic(csp->http->cmd, "HEAD", 4))
1139 const struct parsers *v;
1140 struct list_entry *p;
1142 for (v = server_patterns_light; (err == JB_ERR_OK) && (v->str != NULL); v++)
1144 for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
1146 /* Header crunch()ed in previous run? -> ignore */
1147 if (p->str == NULL) continue;
1149 /* Does the current parser handle this header? */
1150 if (strncmpic(p->str, v->str, v->len) == 0)
1152 err = v->parser(csp, (char **)&(p->str));
1158 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1159 if ((JB_ERR_OK == err)
1160 && (csp->flags & CSP_FLAG_MODIFIED)
1161 && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
1162 && !(csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET))
1166 create_content_length_header(csp->content_length, header, sizeof(header));
1167 err = enlist(csp->headers, header);
1168 if (JB_ERR_OK == err)
1170 log_error(LOG_LEVEL_HEADER,
1171 "Content modified with no Content-Length header set. "
1172 "Created: %s.", header);
1175 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1181 /*********************************************************************
1183 * Function : header_tagger
1185 * Description : Executes all text substitutions from applying
1186 * tag actions and saves the result as tag.
1188 * XXX: Shares enough code with filter_header() and
1189 * pcrs_filter_response() to warrant some helper functions.
1192 * 1 : csp = Current client state (buffers, headers, etc...)
1193 * 2 : header = Header that is used as tagger input
1195 * Returns : JB_ERR_OK on success and always succeeds
1197 *********************************************************************/
1198 static jb_err header_tagger(struct client_state *csp, char *header)
1200 int wanted_filter_type;
1201 int multi_action_index;
1205 struct file_list *fl;
1206 struct re_filterfile_spec *b;
1207 struct list_entry *tag_name;
1209 int found_filters = 0;
1210 const size_t header_length = strlen(header);
1212 if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1214 wanted_filter_type = FT_SERVER_HEADER_TAGGER;
1215 multi_action_index = ACTION_MULTI_SERVER_HEADER_TAGGER;
1219 wanted_filter_type = FT_CLIENT_HEADER_TAGGER;
1220 multi_action_index = ACTION_MULTI_CLIENT_HEADER_TAGGER;
1223 /* Check if there are any filters */
1224 for (i = 0; i < MAX_AF_FILES; i++)
1237 if (0 == found_filters)
1239 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1240 "tagging enabled, but no taggers available.");
1244 for (i = 0; i < MAX_AF_FILES; i++)
1247 if ((NULL == fl) || (NULL == fl->f))
1250 * Either there are no filter files
1251 * left, or this filter file just
1252 * contains no valid filters.
1254 * Continue to be sure we don't miss
1255 * valid filter files that are chained
1256 * after empty or invalid ones.
1261 /* For all filters, */
1262 for (b = fl->f; b; b = b->next)
1264 if (b->type != wanted_filter_type)
1266 /* skip the ones we don't care about, */
1269 /* leaving only taggers that could apply, of which we use the ones, */
1270 for (tag_name = csp->action->multi[multi_action_index]->first;
1271 NULL != tag_name; tag_name = tag_name->next)
1273 /* that do apply, and */
1274 if (strcmp(b->name, tag_name->str) == 0)
1276 char *modified_tag = NULL;
1278 size_t size = header_length;
1279 pcrs_job *joblist = b->joblist;
1281 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1283 if (NULL == joblist)
1285 log_error(LOG_LEVEL_RE_FILTER,
1286 "Tagger %s has empty joblist. Nothing to do.", b->name);
1290 /* execute their pcrs_joblist on the header. */
1291 for (job = joblist; NULL != job; job = job->next)
1293 const int hits = pcrs_execute(job, tag, size, &modified_tag, &size);
1297 /* Success, continue with the modified version. */
1306 /* Tagger doesn't match */
1309 /* Regex failure, log it but continue anyway. */
1310 assert(NULL != header);
1311 log_error(LOG_LEVEL_ERROR,
1312 "Problems with tagger \'%s\' and header \'%s\': %s",
1313 b->name, *header, pcrs_strerror(hits));
1315 freez(modified_tag);
1319 if (b->dynamic) pcrs_free_joblist(joblist);
1321 /* If this tagger matched */
1327 * There is to technical limitation which makes
1328 * it impossible to use empty tags, but I assume
1329 * no one would do it intentionally.
1332 log_error(LOG_LEVEL_INFO,
1333 "Tagger \'%s\' created an empty tag. Ignored.",
1338 if (!list_contains_item(csp->tags, tag))
1340 if (JB_ERR_OK != enlist(csp->tags, tag))
1342 log_error(LOG_LEVEL_ERROR,
1343 "Insufficient memory to add tag \'%s\', "
1344 "based on tagger \'%s\' and header \'%s\'",
1345 tag, b->name, *header);
1349 char *action_message;
1351 * update the action bits right away, to make
1352 * tagging based on tags set by earlier taggers
1353 * of the same kind possible.
1355 if (update_action_bits_for_tag(csp, tag))
1357 action_message = "Action bits updated accordingly.";
1361 action_message = "No action bits update necessary.";
1364 log_error(LOG_LEVEL_HEADER,
1365 "Tagger \'%s\' added tag \'%s\'. %s",
1366 b->name, tag, action_message);
1371 /* XXX: Is this log-worthy? */
1372 log_error(LOG_LEVEL_HEADER,
1373 "Tagger \'%s\' didn't add tag \'%s\'. "
1374 "Tag already present", b->name, tag);
1377 } /* if the tagger matched */
1378 } /* if the tagger applies */
1379 } /* for every tagger that could apply */
1380 } /* for all filters */
1381 } /* for all filter files */
1386 /* here begins the family of parser functions that reformat header lines */
1388 /*********************************************************************
1390 * Function : filter_header
1392 * Description : Executes all text substitutions from all applying
1393 * +(server|client)-header-filter actions on the header.
1394 * Most of the code was copied from pcrs_filter_response,
1395 * including the rather short variable names
1398 * 1 : csp = Current client state (buffers, headers, etc...)
1399 * 2 : header = On input, pointer to header to modify.
1400 * On output, pointer to the modified header, or NULL
1401 * to remove the header. This function frees the
1402 * original string if necessary.
1404 * Returns : JB_ERR_OK on success and always succeeds
1406 *********************************************************************/
1407 static jb_err filter_header(struct client_state *csp, char **header)
1411 size_t size = strlen(*header);
1413 char *newheader = NULL;
1416 struct file_list *fl;
1417 struct re_filterfile_spec *b;
1418 struct list_entry *filtername;
1420 int i, found_filters = 0;
1421 int wanted_filter_type;
1422 int multi_action_index;
1424 if (csp->flags & CSP_FLAG_NO_FILTERING)
1429 if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1431 wanted_filter_type = FT_SERVER_HEADER_FILTER;
1432 multi_action_index = ACTION_MULTI_SERVER_HEADER_FILTER;
1436 wanted_filter_type = FT_CLIENT_HEADER_FILTER;
1437 multi_action_index = ACTION_MULTI_CLIENT_HEADER_FILTER;
1441 * Need to check the set of re_filterfiles...
1443 for (i = 0; i < MAX_AF_FILES; i++)
1456 if (0 == found_filters)
1458 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1459 "header filtering enabled, but no matching filters available.");
1463 for (i = 0; i < MAX_AF_FILES; i++)
1466 if ((NULL == fl) || (NULL == fl->f))
1469 * Either there are no filter files
1470 * left, or this filter file just
1471 * contains no valid filters.
1473 * Continue to be sure we don't miss
1474 * valid filter files that are chained
1475 * after empty or invalid ones.
1480 * For all applying +filter actions, look if a filter by that
1481 * name exists and if yes, execute its pcrs_joblist on the
1484 for (b = fl->f; b; b = b->next)
1486 if (b->type != wanted_filter_type)
1488 /* Skip other filter types */
1492 for (filtername = csp->action->multi[multi_action_index]->first;
1493 filtername ; filtername = filtername->next)
1495 if (strcmp(b->name, filtername->str) == 0)
1497 int current_hits = 0;
1498 pcrs_job *joblist = b->joblist;
1500 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1502 if (NULL == joblist)
1504 log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
1508 log_error(LOG_LEVEL_RE_FILTER, "filtering \'%s\' (size %d) with \'%s\' ...",
1509 *header, size, b->name);
1511 /* Apply all jobs from the joblist */
1512 for (job = joblist; NULL != job; job = job->next)
1514 matches = pcrs_execute(job, *header, size, &newheader, &size);
1517 current_hits += matches;
1518 log_error(LOG_LEVEL_HEADER, "Transforming \"%s\" to \"%s\"", *header, newheader);
1520 *header = newheader;
1522 else if ( 0 == matches )
1524 /* Filter doesn't change header */
1530 log_error(LOG_LEVEL_ERROR, "Filtering \'%s\' with \'%s\' didn't work out: %s",
1531 *header, b->name, pcrs_strerror(matches));
1532 if (newheader != NULL)
1534 log_error(LOG_LEVEL_ERROR, "Freeing what's left: %s", newheader);
1540 if (b->dynamic) pcrs_free_joblist(joblist);
1542 log_error(LOG_LEVEL_RE_FILTER, "... produced %d hits (new size %d).", current_hits, size);
1543 hits += current_hits;
1550 * Additionally checking for hits is important because if
1551 * the continue hack is triggered, server headers can
1552 * arrive empty to separate multiple heads from each other.
1554 if ((0 == size) && hits)
1556 log_error(LOG_LEVEL_HEADER, "Removing empty header %s", *header);
1564 /*********************************************************************
1566 * Function : server_connection
1568 * Description : Makes sure a proper "Connection:" header is
1569 * set and signals connection_header_adder to
1573 * 1 : csp = Current client state (buffers, headers, etc...)
1574 * 2 : header = On input, pointer to header to modify.
1575 * On output, pointer to the modified header, or NULL
1576 * to remove the header. This function frees the
1577 * original string if necessary.
1579 * Returns : JB_ERR_OK on success, or
1580 * JB_ERR_MEMORY on out-of-memory error.
1582 *********************************************************************/
1583 static jb_err server_connection(struct client_state *csp, char **header)
1585 if (!strcmpic(*header, "Connection: keep-alive")
1586 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1587 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
1591 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1592 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1594 csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
1597 if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE))
1599 log_error(LOG_LEVEL_HEADER,
1600 "Keeping the server header '%s' around.", *header);
1603 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1605 char *old_header = *header;
1607 *header = strdup("Connection: close");
1610 return JB_ERR_MEMORY;
1612 log_error(LOG_LEVEL_HEADER, "Replaced: \'%s\' with \'%s\'", old_header, *header);
1617 /* Signal server_connection_adder() to return early. */
1618 csp->flags |= CSP_FLAG_SERVER_CONNECTION_HEADER_SET;
1624 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1625 /*********************************************************************
1627 * Function : server_keep_alive
1629 * Description : Stores the server's keep alive timeout.
1632 * 1 : csp = Current client state (buffers, headers, etc...)
1633 * 2 : header = On input, pointer to header to modify.
1634 * On output, pointer to the modified header, or NULL
1635 * to remove the header. This function frees the
1636 * original string if necessary.
1638 * Returns : JB_ERR_OK.
1640 *********************************************************************/
1641 static jb_err server_keep_alive(struct client_state *csp, char **header)
1643 unsigned int keep_alive_timeout;
1644 const char *timeout_position = strstr(*header, "timeout=");
1646 if ((NULL == timeout_position)
1647 || (1 != sscanf(timeout_position, "timeout=%u", &keep_alive_timeout)))
1649 log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header);
1653 if (keep_alive_timeout < csp->server_connection.keep_alive_timeout)
1655 log_error(LOG_LEVEL_HEADER,
1656 "Reducing keep-alive timeout from %u to %u.",
1657 csp->server_connection.keep_alive_timeout, keep_alive_timeout);
1658 csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1662 /* XXX: Is this log worthy? */
1663 log_error(LOG_LEVEL_HEADER,
1664 "Server keep-alive timeout is %u. Sticking with %u.",
1665 keep_alive_timeout, csp->server_connection.keep_alive_timeout);
1673 /*********************************************************************
1675 * Function : client_keep_alive
1677 * Description : Stores the client's keep alive timeout.
1680 * 1 : csp = Current client state (buffers, headers, etc...)
1681 * 2 : header = On input, pointer to header to modify.
1682 * On output, pointer to the modified header, or NULL
1683 * to remove the header. This function frees the
1684 * original string if necessary.
1686 * Returns : JB_ERR_OK.
1688 *********************************************************************/
1689 static jb_err client_keep_alive(struct client_state *csp, char **header)
1691 unsigned int keep_alive_timeout;
1692 const char *timeout_position = strstr(*header, ": ");
1694 if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1696 log_error(LOG_LEVEL_HEADER,
1697 "keep-alive support is disabled. Crunching: %s.", *header);
1702 if ((NULL == timeout_position)
1703 || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout)))
1705 log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header);
1709 if (keep_alive_timeout < csp->config->keep_alive_timeout)
1711 log_error(LOG_LEVEL_HEADER,
1712 "Reducing keep-alive timeout from %u to %u.",
1713 csp->config->keep_alive_timeout, keep_alive_timeout);
1714 csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1718 /* XXX: Is this log worthy? */
1719 log_error(LOG_LEVEL_HEADER,
1720 "Client keep-alive timeout is %u. Sticking with %u.",
1721 keep_alive_timeout, csp->config->keep_alive_timeout);
1727 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1731 /*********************************************************************
1733 * Function : client_connection
1735 * Description : Makes sure a proper "Connection:" header is
1736 * set and signals connection_header_adder
1740 * 1 : csp = Current client state (buffers, headers, etc...)
1741 * 2 : header = On input, pointer to header to modify.
1742 * On output, pointer to the modified header, or NULL
1743 * to remove the header. This function frees the
1744 * original string if necessary.
1746 * Returns : JB_ERR_OK on success, or
1747 * JB_ERR_MEMORY on out-of-memory error.
1749 *********************************************************************/
1750 static jb_err client_connection(struct client_state *csp, char **header)
1752 static const char connection_close[] = "Connection: close";
1754 if (!strcmpic(*header, connection_close))
1756 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1757 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
1759 if (!strcmpic(csp->http->ver, "HTTP/1.1"))
1761 log_error(LOG_LEVEL_HEADER,
1762 "Removing \'%s\' to imply keep-alive.", *header);
1767 char *old_header = *header;
1769 *header = strdup("Connection: keep-alive");
1772 return JB_ERR_MEMORY;
1774 log_error(LOG_LEVEL_HEADER,
1775 "Replaced: \'%s\' with \'%s\'", old_header, *header);
1778 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1782 log_error(LOG_LEVEL_HEADER,
1783 "Keeping the client header '%s' around. "
1784 "The connection will not be kept alive.",
1786 csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1789 char *old_header = *header;
1791 *header = strdup(connection_close);
1794 return JB_ERR_MEMORY;
1796 log_error(LOG_LEVEL_HEADER,
1797 "Replaced: \'%s\' with \'%s\'", old_header, *header);
1799 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1801 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1804 log_error(LOG_LEVEL_HEADER,
1805 "Keeping the client header '%s' around. "
1806 "The server connection will be kept alive if possible.",
1808 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1810 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1812 /* Signal client_connection_adder() to return early. */
1813 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET;
1819 /*********************************************************************
1821 * Function : crumble
1823 * Description : This is called if a header matches a pattern to "crunch"
1826 * 1 : csp = Current client state (buffers, headers, etc...)
1827 * 2 : header = On input, pointer to header to modify.
1828 * On output, pointer to the modified header, or NULL
1829 * to remove the header. This function frees the
1830 * original string if necessary.
1832 * Returns : JB_ERR_OK on success, or
1833 * JB_ERR_MEMORY on out-of-memory error.
1835 *********************************************************************/
1836 static jb_err crumble(struct client_state *csp, char **header)
1839 log_error(LOG_LEVEL_HEADER, "crumble crunched: %s!", *header);
1845 /*********************************************************************
1847 * Function : crunch_server_header
1849 * Description : Crunch server header if it matches a string supplied by the
1850 * user. Called from `sed'.
1853 * 1 : csp = Current client state (buffers, headers, etc...)
1854 * 2 : header = On input, pointer to header to modify.
1855 * On output, pointer to the modified header, or NULL
1856 * to remove the header. This function frees the
1857 * original string if necessary.
1859 * Returns : JB_ERR_OK on success and always succeeds
1861 *********************************************************************/
1862 static jb_err crunch_server_header(struct client_state *csp, char **header)
1864 const char *crunch_pattern;
1866 /* Do we feel like crunching? */
1867 if ((csp->action->flags & ACTION_CRUNCH_SERVER_HEADER))
1869 crunch_pattern = csp->action->string[ACTION_STRING_SERVER_HEADER];
1871 /* Is the current header the lucky one? */
1872 if (strstr(*header, crunch_pattern))
1874 log_error(LOG_LEVEL_HEADER, "Crunching server header: %s (contains: %s)", *header, crunch_pattern);
1883 /*********************************************************************
1885 * Function : server_content_type
1887 * Description : Set the content-type for filterable types (text/.*,
1888 * .*xml.*, javascript and image/gif) unless filtering has been
1889 * forbidden (CT_TABOO) while parsing earlier headers.
1890 * NOTE: Since text/plain is commonly used by web servers
1891 * for files whose correct type is unknown, we don't
1892 * set CT_TEXT for it.
1895 * 1 : csp = Current client state (buffers, headers, etc...)
1896 * 2 : header = On input, pointer to header to modify.
1897 * On output, pointer to the modified header, or NULL
1898 * to remove the header. This function frees the
1899 * original string if necessary.
1901 * Returns : JB_ERR_OK on success, or
1902 * JB_ERR_MEMORY on out-of-memory error.
1904 *********************************************************************/
1905 static jb_err server_content_type(struct client_state *csp, char **header)
1907 /* Remove header if it isn't the first Content-Type header */
1908 if ((csp->content_type & CT_DECLARED))
1911 * Another, slightly slower, way to see if
1912 * we already parsed another Content-Type header.
1914 assert(NULL != get_header_value(csp->headers, "Content-Type:"));
1916 log_error(LOG_LEVEL_ERROR,
1917 "Multiple Content-Type headers. Removing and ignoring: \'%s\'",
1925 * Signal that the Content-Type has been set.
1927 csp->content_type |= CT_DECLARED;
1929 if (!(csp->content_type & CT_TABOO))
1932 * XXX: The assumption that text/plain is a sign of
1933 * binary data seems to be somewhat unreasonable nowadays
1934 * and should be dropped after 3.0.8 is out.
1936 if ((strstr(*header, "text/") && !strstr(*header, "plain"))
1937 || strstr(*header, "xml")
1938 || strstr(*header, "application/x-javascript"))
1940 csp->content_type |= CT_TEXT;
1942 else if (strstr(*header, "image/gif"))
1944 csp->content_type |= CT_GIF;
1949 * Are we messing with the content type?
1951 if (csp->action->flags & ACTION_CONTENT_TYPE_OVERWRITE)
1954 * Make sure the user doesn't accidently
1955 * change the content type of binary documents.
1957 if ((csp->content_type & CT_TEXT) || (csp->action->flags & ACTION_FORCE_TEXT_MODE))
1960 *header = strdup("Content-Type: ");
1961 string_append(header, csp->action->string[ACTION_STRING_CONTENT_TYPE]);
1965 log_error(LOG_LEVEL_HEADER, "Insufficient memory to replace Content-Type!");
1966 return JB_ERR_MEMORY;
1968 log_error(LOG_LEVEL_HEADER, "Modified: %s!", *header);
1972 log_error(LOG_LEVEL_HEADER, "%s not replaced. "
1973 "It doesn't look like a content type that should be filtered. "
1974 "Enable force-text-mode if you know what you're doing.", *header);
1982 /*********************************************************************
1984 * Function : server_transfer_coding
1986 * Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses
1987 * - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked"
1988 * - Remove header if body was chunked but has been
1989 * de-chunked for filtering.
1992 * 1 : csp = Current client state (buffers, headers, etc...)
1993 * 2 : header = On input, pointer to header to modify.
1994 * On output, pointer to the modified header, or NULL
1995 * to remove the header. This function frees the
1996 * original string if necessary.
1998 * Returns : JB_ERR_OK on success, or
1999 * JB_ERR_MEMORY on out-of-memory error.
2001 *********************************************************************/
2002 static jb_err server_transfer_coding(struct client_state *csp, char **header)
2005 * Turn off pcrs and gif filtering if body compressed
2007 if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
2011 * XXX: Added to test if we could use CT_GZIP and CT_DEFLATE here.
2013 log_error(LOG_LEVEL_INFO, "Marking content type for %s as CT_TABOO because of %s.",
2014 csp->http->cmd, *header);
2015 #endif /* def FEATURE_ZLIB */
2016 csp->content_type = CT_TABOO;
2020 * Raise flag if body chunked
2022 if (strstr(*header, "chunked"))
2024 csp->flags |= CSP_FLAG_CHUNKED;
2027 * If the body was modified, it has been de-chunked first
2028 * and the header must be removed.
2030 * FIXME: If there is more than one transfer encoding,
2031 * only the "chunked" part should be removed here.
2033 if (csp->flags & CSP_FLAG_MODIFIED)
2035 log_error(LOG_LEVEL_HEADER, "Removing: %s", *header);
2044 /*********************************************************************
2046 * Function : server_content_encoding
2048 * Description : This function is run twice for each request,
2049 * unless FEATURE_ZLIB and filtering are disabled.
2051 * The first run is used to check if the content
2052 * is compressed, if FEATURE_ZLIB is disabled
2053 * filtering is then disabled as well, if FEATURE_ZLIB
2054 * is enabled the content is marked for decompression.
2056 * The second run is used to remove the Content-Encoding
2057 * header if the decompression was successful.
2060 * 1 : csp = Current client state (buffers, headers, etc...)
2061 * 2 : header = On input, pointer to header to modify.
2062 * On output, pointer to the modified header, or NULL
2063 * to remove the header. This function frees the
2064 * original string if necessary.
2066 * Returns : JB_ERR_OK on success, or
2067 * JB_ERR_MEMORY on out-of-memory error.
2069 *********************************************************************/
2070 static jb_err server_content_encoding(struct client_state *csp, char **header)
2073 if ((csp->flags & CSP_FLAG_MODIFIED)
2074 && (csp->content_type & (CT_GZIP | CT_DEFLATE)))
2077 * We successfully decompressed the content,
2078 * and have to clean the header now, so the
2079 * client no longer expects compressed data..
2081 * XXX: There is a difference between cleaning
2082 * and removing it completely.
2084 log_error(LOG_LEVEL_HEADER, "Crunching: %s", *header);
2087 else if (strstr(*header, "gzip"))
2089 /* Mark for gzip decompression */
2090 csp->content_type |= CT_GZIP;
2092 else if (strstr(*header, "deflate"))
2094 /* Mark for zlib decompression */
2095 csp->content_type |= CT_DEFLATE;
2097 else if (strstr(*header, "compress"))
2100 * We can't decompress this; therefore we can't filter
2103 csp->content_type |= CT_TABOO;
2105 #else /* !defined(FEATURE_ZLIB) */
2106 if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
2109 * Body is compressed, turn off pcrs and gif filtering.
2111 csp->content_type |= CT_TABOO;
2114 * Log a warning if the user expects the content to be filtered.
2116 if ((csp->rlist != NULL) &&
2117 (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
2119 log_error(LOG_LEVEL_INFO,
2120 "Compressed content detected, content filtering disabled. "
2121 "Consider recompiling Privoxy with zlib support or "
2122 "enable the prevent-compression action.");
2125 #endif /* defined(FEATURE_ZLIB) */
2132 /*********************************************************************
2134 * Function : server_adjust_content_length
2136 * Description : Adjust Content-Length header if we modified
2140 * 1 : csp = Current client state (buffers, headers, etc...)
2141 * 2 : header = On input, pointer to header to modify.
2142 * On output, pointer to the modified header, or NULL
2143 * to remove the header. This function frees the
2144 * original string if necessary.
2146 * Returns : JB_ERR_OK on success, or
2147 * JB_ERR_MEMORY on out-of-memory error.
2149 *********************************************************************/
2150 static jb_err server_adjust_content_length(struct client_state *csp, char **header)
2152 /* Regenerate header if the content was modified. */
2153 if (csp->flags & CSP_FLAG_MODIFIED)
2155 const size_t header_length = 50;
2157 *header = malloc(header_length);
2158 if (*header == NULL)
2160 return JB_ERR_MEMORY;
2162 create_content_length_header(csp->content_length, *header, header_length);
2163 log_error(LOG_LEVEL_HEADER,
2164 "Adjusted Content-Length to %llu", csp->content_length);
2171 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2172 /*********************************************************************
2174 * Function : server_save_content_length
2176 * Description : Save the Content-Length sent by the server.
2179 * 1 : csp = Current client state (buffers, headers, etc...)
2180 * 2 : header = On input, pointer to header to modify.
2181 * On output, pointer to the modified header, or NULL
2182 * to remove the header. This function frees the
2183 * original string if necessary.
2185 * Returns : JB_ERR_OK on success, or
2186 * JB_ERR_MEMORY on out-of-memory error.
2188 *********************************************************************/
2189 static jb_err server_save_content_length(struct client_state *csp, char **header)
2191 unsigned long long content_length = 0;
2193 assert(*(*header+14) == ':');
2196 if (1 != sscanf(*header+14, ": %I64u", &content_length))
2198 if (1 != sscanf(*header+14, ": %llu", &content_length))
2201 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2206 csp->expected_content_length = content_length;
2207 csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
2208 csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2213 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2216 /*********************************************************************
2218 * Function : server_content_md5
2220 * Description : Crumble any Content-MD5 headers if the document was
2221 * modified. FIXME: Should we re-compute instead?
2224 * 1 : csp = Current client state (buffers, headers, etc...)
2225 * 2 : header = On input, pointer to header to modify.
2226 * On output, pointer to the modified header, or NULL
2227 * to remove the header. This function frees the
2228 * original string if necessary.
2230 * Returns : JB_ERR_OK on success, or
2231 * JB_ERR_MEMORY on out-of-memory error.
2233 *********************************************************************/
2234 static jb_err server_content_md5(struct client_state *csp, char **header)
2236 if (csp->flags & CSP_FLAG_MODIFIED)
2238 log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5");
2246 /*********************************************************************
2248 * Function : server_content_disposition
2250 * Description : If enabled, blocks or modifies the "Content-Disposition" header.
2251 * Called from `sed'.
2254 * 1 : csp = Current client state (buffers, headers, etc...)
2255 * 2 : header = On input, pointer to header to modify.
2256 * On output, pointer to the modified header, or NULL
2257 * to remove the header. This function frees the
2258 * original string if necessary.
2260 * Returns : JB_ERR_OK on success, or
2261 * JB_ERR_MEMORY on out-of-memory error.
2263 *********************************************************************/
2264 static jb_err server_content_disposition(struct client_state *csp, char **header)
2269 * Are we messing with the Content-Disposition header?
2271 if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0)
2277 newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION];
2279 if ((newval == NULL) || (0 == strcmpic(newval, "block")))
2282 * Blocking content-disposition header
2284 log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2291 * Replacing Content-Disposition header
2294 *header = strdup("Content-Disposition: ");
2295 string_append(header, newval);
2297 if (*header != NULL)
2299 log_error(LOG_LEVEL_HEADER,
2300 "Content-Disposition header crunched and replaced with: %s", *header);
2303 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2307 /*********************************************************************
2309 * Function : server_last_modified
2311 * Description : Changes Last-Modified header to the actual date
2312 * to help hide-if-modified-since.
2313 * Called from `sed'.
2316 * 1 : csp = Current client state (buffers, headers, etc...)
2317 * 2 : header = On input, pointer to header to modify.
2318 * On output, pointer to the modified header, or NULL
2319 * to remove the header. This function frees the
2320 * original string if necessary.
2322 * Returns : JB_ERR_OK on success, or
2323 * JB_ERR_MEMORY on out-of-memory error.
2325 *********************************************************************/
2326 static jb_err server_last_modified(struct client_state *csp, char **header)
2329 char buf[BUFFER_SIZE];
2332 #ifdef HAVE_GMTIME_R
2335 struct tm *timeptr = NULL;
2336 time_t now, last_modified;
2337 long int days, hours, minutes, seconds;
2340 * Are we messing with the Last-Modified header?
2342 if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0)
2348 newval = csp->action->string[ACTION_STRING_LAST_MODIFIED];
2350 if (0 == strcmpic(newval, "block") )
2353 * Blocking Last-Modified header. Useless but why not.
2355 log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2359 else if (0 == strcmpic(newval, "reset-to-request-time"))
2362 * Setting Last-Modified Header to now.
2364 get_http_time(0, buf, sizeof(buf));
2366 *header = strdup("Last-Modified: ");
2367 string_append(header, buf);
2369 if (*header == NULL)
2371 log_error(LOG_LEVEL_HEADER, "Insufficient memory. Last-Modified header got lost, boohoo.");
2375 log_error(LOG_LEVEL_HEADER, "Reset to present time: %s", *header);
2378 else if (0 == strcmpic(newval, "randomize"))
2380 const char *header_time = *header + sizeof("Last-Modified:");
2382 log_error(LOG_LEVEL_HEADER, "Randomizing: %s", *header);
2384 #ifdef HAVE_GMTIME_R
2385 gmtime_r(&now, &gmt);
2386 #elif defined(MUTEX_LOCKS_AVAILABLE)
2387 privoxy_mutex_lock(&gmtime_mutex);
2389 privoxy_mutex_unlock(&gmtime_mutex);
2393 if (JB_ERR_OK != parse_header_time(header_time, &last_modified))
2395 log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
2400 long int rtime = (long int)difftime(now, last_modified);
2403 const int negative_delta = (rtime < 0);
2408 log_error(LOG_LEVEL_HEADER, "Server time in the future.");
2410 rtime = pick_from_range(rtime);
2415 last_modified += rtime;
2416 #ifdef HAVE_GMTIME_R
2417 timeptr = gmtime_r(&last_modified, &gmt);
2418 #elif defined(MUTEX_LOCKS_AVAILABLE)
2419 privoxy_mutex_lock(&gmtime_mutex);
2420 timeptr = gmtime(&last_modified);
2421 privoxy_mutex_unlock(&gmtime_mutex);
2423 timeptr = gmtime(&last_modified);
2425 if ((NULL == timeptr) || !strftime(newheader,
2426 sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
2428 log_error(LOG_LEVEL_ERROR,
2429 "Randomizing '%s' failed. Crunching the header without replacement.",
2436 *header = strdup("Last-Modified: ");
2437 string_append(header, newheader);
2439 if (*header == NULL)
2441 log_error(LOG_LEVEL_ERROR, "Insufficient memory, header crunched without replacement.");
2442 return JB_ERR_MEMORY;
2445 days = rtime / (3600 * 24);
2446 hours = rtime / 3600 % 24;
2447 minutes = rtime / 60 % 60;
2448 seconds = rtime % 60;
2450 log_error(LOG_LEVEL_HEADER,
2451 "Randomized: %s (added %d da%s %d hou%s %d minut%s %d second%s",
2452 *header, days, (days == 1) ? "y" : "ys", hours, (hours == 1) ? "r" : "rs",
2453 minutes, (minutes == 1) ? "e" : "es", seconds, (seconds == 1) ? ")" : "s)");
2457 log_error(LOG_LEVEL_HEADER, "Randomized ... or not. No time difference to work with.");
2466 /*********************************************************************
2468 * Function : client_accept_encoding
2470 * Description : Rewrite the client's Accept-Encoding header so that
2471 * if doesn't allow compression, if the action applies.
2472 * Note: For HTTP/1.0 the absence of the header is enough.
2475 * 1 : csp = Current client state (buffers, headers, etc...)
2476 * 2 : header = On input, pointer to header to modify.
2477 * On output, pointer to the modified header, or NULL
2478 * to remove the header. This function frees the
2479 * original string if necessary.
2481 * Returns : JB_ERR_OK on success, or
2482 * JB_ERR_MEMORY on out-of-memory error.
2484 *********************************************************************/
2485 static jb_err client_accept_encoding(struct client_state *csp, char **header)
2487 if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
2489 log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content");
2493 /* Temporarily disable the correct behaviour to
2494 * work around a PHP bug.
2496 * if (!strcmpic(csp->http->ver, "HTTP/1.1"))
2498 * *header = strdup("Accept-Encoding: identity;q=1.0, *;q=0");
2499 * if (*header == NULL)
2501 * return JB_ERR_MEMORY;
2512 /*********************************************************************
2514 * Function : client_te
2516 * Description : Rewrite the client's TE header so that
2517 * if doesn't allow compression, if the action applies.
2520 * 1 : csp = Current client state (buffers, headers, etc...)
2521 * 2 : header = On input, pointer to header to modify.
2522 * On output, pointer to the modified header, or NULL
2523 * to remove the header. This function frees the
2524 * original string if necessary.
2526 * Returns : JB_ERR_OK on success, or
2527 * JB_ERR_MEMORY on out-of-memory error.
2529 *********************************************************************/
2530 static jb_err client_te(struct client_state *csp, char **header)
2532 if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
2535 log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress transfer");
2542 /*********************************************************************
2544 * Function : client_referrer
2546 * Description : Handle the "referer" config setting properly.
2547 * Called from `sed'.
2550 * 1 : csp = Current client state (buffers, headers, etc...)
2551 * 2 : header = On input, pointer to header to modify.
2552 * On output, pointer to the modified header, or NULL
2553 * to remove the header. This function frees the
2554 * original string if necessary.
2556 * Returns : JB_ERR_OK on success, or
2557 * JB_ERR_MEMORY on out-of-memory error.
2559 *********************************************************************/
2560 static jb_err client_referrer(struct client_state *csp, char **header)
2562 const char *parameter;
2563 /* booleans for parameters we have to check multiple times */
2564 int parameter_conditional_block;
2565 int parameter_conditional_forge;
2567 #ifdef FEATURE_FORCE_LOAD
2569 * Since the referrer can include the prefix even
2570 * if the request itself is non-forced, we must
2571 * clean it unconditionally.
2573 * XXX: strclean is too broad
2575 strclean(*header, FORCE_PREFIX);
2576 #endif /* def FEATURE_FORCE_LOAD */
2578 if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
2580 /* Nothing left to do */
2584 parameter = csp->action->string[ACTION_STRING_REFERER];
2585 assert(parameter != NULL);
2586 parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
2587 parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
2589 if (!parameter_conditional_block && !parameter_conditional_forge)
2592 * As conditional-block and conditional-forge are the only
2593 * parameters that rely on the original referrer, we can
2594 * remove it now for all the others.
2599 if (0 == strcmpic(parameter, "block"))
2601 log_error(LOG_LEVEL_HEADER, "Referer crunched!");
2604 else if (parameter_conditional_block || parameter_conditional_forge)
2606 return handle_conditional_hide_referrer_parameter(header,
2607 csp->http->hostport, parameter_conditional_block);
2609 else if (0 == strcmpic(parameter, "forge"))
2611 return create_forged_referrer(header, csp->http->hostport);
2615 /* interpret parameter as user-supplied referer to fake */
2616 return create_fake_referrer(header, parameter);
2621 /*********************************************************************
2623 * Function : client_accept_language
2625 * Description : Handle the "Accept-Language" config setting properly.
2626 * Called from `sed'.
2629 * 1 : csp = Current client state (buffers, headers, etc...)
2630 * 2 : header = On input, pointer to header to modify.
2631 * On output, pointer to the modified header, or NULL
2632 * to remove the header. This function frees the
2633 * original string if necessary.
2635 * Returns : JB_ERR_OK on success, or
2636 * JB_ERR_MEMORY on out-of-memory error.
2638 *********************************************************************/
2639 static jb_err client_accept_language(struct client_state *csp, char **header)
2644 * Are we messing with the Accept-Language?
2646 if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0)
2648 /*I don't think so*/
2652 newval = csp->action->string[ACTION_STRING_LANGUAGE];
2654 if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
2657 * Blocking Accept-Language header
2659 log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!");
2666 * Replacing Accept-Language header
2669 *header = strdup("Accept-Language: ");
2670 string_append(header, newval);
2672 if (*header == NULL)
2674 log_error(LOG_LEVEL_ERROR,
2675 "Insufficient memory. Accept-Language header crunched without replacement.");
2679 log_error(LOG_LEVEL_HEADER,
2680 "Accept-Language header crunched and replaced with: %s", *header);
2683 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2687 /*********************************************************************
2689 * Function : crunch_client_header
2691 * Description : Crunch client header if it matches a string supplied by the
2692 * user. Called from `sed'.
2695 * 1 : csp = Current client state (buffers, headers, etc...)
2696 * 2 : header = On input, pointer to header to modify.
2697 * On output, pointer to the modified header, or NULL
2698 * to remove the header. This function frees the
2699 * original string if necessary.
2701 * Returns : JB_ERR_OK on success and always succeeds
2703 *********************************************************************/
2704 static jb_err crunch_client_header(struct client_state *csp, char **header)
2706 const char *crunch_pattern;
2708 /* Do we feel like crunching? */
2709 if ((csp->action->flags & ACTION_CRUNCH_CLIENT_HEADER))
2711 crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER];
2713 /* Is the current header the lucky one? */
2714 if (strstr(*header, crunch_pattern))
2716 log_error(LOG_LEVEL_HEADER, "Crunching client header: %s (contains: %s)", *header, crunch_pattern);
2724 /*********************************************************************
2726 * Function : client_uagent
2728 * Description : Handle the "user-agent" config setting properly
2729 * and remember its original value to enable browser
2730 * bug workarounds. Called from `sed'.
2733 * 1 : csp = Current client state (buffers, headers, etc...)
2734 * 2 : header = On input, pointer to header to modify.
2735 * On output, pointer to the modified header, or NULL
2736 * to remove the header. This function frees the
2737 * original string if necessary.
2739 * Returns : JB_ERR_OK on success, or
2740 * JB_ERR_MEMORY on out-of-memory error.
2742 *********************************************************************/
2743 static jb_err client_uagent(struct client_state *csp, char **header)
2747 if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0)
2752 newval = csp->action->string[ACTION_STRING_USER_AGENT];
2759 *header = strdup("User-Agent: ");
2760 string_append(header, newval);
2762 log_error(LOG_LEVEL_HEADER, "Modified: %s", *header);
2764 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2768 /*********************************************************************
2770 * Function : client_ua
2772 * Description : Handle "ua-" headers properly. Called from `sed'.
2775 * 1 : csp = Current client state (buffers, headers, etc...)
2776 * 2 : header = On input, pointer to header to modify.
2777 * On output, pointer to the modified header, or NULL
2778 * to remove the header. This function frees the
2779 * original string if necessary.
2781 * Returns : JB_ERR_OK on success, or
2782 * JB_ERR_MEMORY on out-of-memory error.
2784 *********************************************************************/
2785 static jb_err client_ua(struct client_state *csp, char **header)
2787 if ((csp->action->flags & ACTION_HIDE_USER_AGENT) != 0)
2789 log_error(LOG_LEVEL_HEADER, "crunched User-Agent!");
2797 /*********************************************************************
2799 * Function : client_from
2801 * Description : Handle the "from" config setting properly.
2802 * Called from `sed'.
2805 * 1 : csp = Current client state (buffers, headers, etc...)
2806 * 2 : header = On input, pointer to header to modify.
2807 * On output, pointer to the modified header, or NULL
2808 * to remove the header. This function frees the
2809 * original string if necessary.
2811 * Returns : JB_ERR_OK on success, or
2812 * JB_ERR_MEMORY on out-of-memory error.
2814 *********************************************************************/
2815 static jb_err client_from(struct client_state *csp, char **header)
2819 if ((csp->action->flags & ACTION_HIDE_FROM) == 0)
2826 newval = csp->action->string[ACTION_STRING_FROM];
2829 * Are we blocking the e-mail address?
2831 if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
2833 log_error(LOG_LEVEL_HEADER, "crunched From!");
2837 log_error(LOG_LEVEL_HEADER, " modified");
2839 *header = strdup("From: ");
2840 string_append(header, newval);
2842 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2846 /*********************************************************************
2848 * Function : client_send_cookie
2850 * Description : Crunches the "cookie" header if necessary.
2851 * Called from `sed'.
2853 * XXX: Stupid name, doesn't send squat.
2856 * 1 : csp = Current client state (buffers, headers, etc...)
2857 * 2 : header = On input, pointer to header to modify.
2858 * On output, pointer to the modified header, or NULL
2859 * to remove the header. This function frees the
2860 * original string if necessary.
2862 * Returns : JB_ERR_OK on success, or
2863 * JB_ERR_MEMORY on out-of-memory error.
2865 *********************************************************************/
2866 static jb_err client_send_cookie(struct client_state *csp, char **header)
2868 if (csp->action->flags & ACTION_NO_COOKIE_READ)
2870 log_error(LOG_LEVEL_HEADER, "Crunched outgoing cookie: %s", *header);
2878 /*********************************************************************
2880 * Function : client_x_forwarded
2882 * Description : Handle the "x-forwarded-for" config setting properly,
2883 * also used in the add_client_headers list. Called from `sed'.
2886 * 1 : csp = Current client state (buffers, headers, etc...)
2887 * 2 : header = On input, pointer to header to modify.
2888 * On output, pointer to the modified header, or NULL
2889 * to remove the header. This function frees the
2890 * original string if necessary.
2892 * Returns : JB_ERR_OK on success, or
2893 * JB_ERR_MEMORY on out-of-memory error.
2895 *********************************************************************/
2896 jb_err client_x_forwarded(struct client_state *csp, char **header)
2898 if (0 != (csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR))
2900 const char *parameter = csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR];
2902 if (0 == strcmpic(parameter, "block"))
2905 log_error(LOG_LEVEL_HEADER, "crunched x-forwarded-for!");
2907 else if (0 == strcmpic(parameter, "add"))
2909 string_append(header, ", ");
2910 string_append(header, csp->ip_addr_str);
2912 if (*header == NULL)
2914 return JB_ERR_MEMORY;
2916 log_error(LOG_LEVEL_HEADER,
2917 "Appended client IP address to %s", *header);
2918 csp->flags |= CSP_FLAG_X_FORWARDED_FOR_APPENDED;
2922 log_error(LOG_LEVEL_FATAL,
2923 "Invalid change-x-forwarded-for parameter: '%s'", parameter);
2931 /*********************************************************************
2933 * Function : client_max_forwards
2935 * Description : If the HTTP method is OPTIONS or TRACE, subtract one
2936 * from the value of the Max-Forwards header field.
2939 * 1 : csp = Current client state (buffers, headers, etc...)
2940 * 2 : header = On input, pointer to header to modify.
2941 * On output, pointer to the modified header, or NULL
2942 * to remove the header. This function frees the
2943 * original string if necessary.
2945 * Returns : JB_ERR_OK on success, or
2946 * JB_ERR_MEMORY on out-of-memory error.
2948 *********************************************************************/
2949 static jb_err client_max_forwards(struct client_state *csp, char **header)
2953 if ((0 == strcmpic(csp->http->gpc, "trace")) ||
2954 (0 == strcmpic(csp->http->gpc, "options")))
2956 assert(*(*header+12) == ':');
2957 if (1 == sscanf(*header+12, ": %d", &max_forwards))
2959 if (max_forwards > 0)
2961 snprintf(*header, strlen(*header)+1, "Max-Forwards: %d", --max_forwards);
2962 log_error(LOG_LEVEL_HEADER,
2963 "Max-Forwards value for %s request reduced to %d.",
2964 csp->http->gpc, max_forwards);
2966 else if (max_forwards < 0)
2968 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2974 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2983 /*********************************************************************
2985 * Function : client_host
2987 * Description : If the request URI did not contain host and
2988 * port information, parse and evaluate the Host
2991 * Also, kill ill-formed HOST: headers as sent by
2992 * Apple's iTunes software when used with a proxy.
2995 * 1 : csp = Current client state (buffers, headers, etc...)
2996 * 2 : header = On input, pointer to header to modify.
2997 * On output, pointer to the modified header, or NULL
2998 * to remove the header. This function frees the
2999 * original string if necessary.
3001 * Returns : JB_ERR_OK on success, or
3002 * JB_ERR_MEMORY on out-of-memory error.
3004 *********************************************************************/
3005 static jb_err client_host(struct client_state *csp, char **header)
3010 * If the header field name is all upper-case, chances are that it's
3011 * an ill-formed one from iTunes. BTW, killing innocent headers here is
3012 * not a problem -- they are regenerated later.
3014 if ((*header)[1] == 'O')
3016 log_error(LOG_LEVEL_HEADER, "Killed all-caps Host header line: %s", *header);
3021 if (!csp->http->hostport || (*csp->http->hostport == '*') ||
3022 *csp->http->hostport == ' ' || *csp->http->hostport == '\0')
3025 if (NULL == (p = strdup((*header)+6)))
3027 return JB_ERR_MEMORY;
3030 if (NULL == (q = strdup(p)))
3033 return JB_ERR_MEMORY;
3036 freez(csp->http->hostport);
3037 csp->http->hostport = p;
3038 freez(csp->http->host);
3039 csp->http->host = q;
3040 q = strchr(csp->http->host, ':');
3043 /* Terminate hostname and evaluate port string */
3045 csp->http->port = atoi(q);
3049 csp->http->port = csp->http->ssl ? 443 : 80;
3052 log_error(LOG_LEVEL_HEADER, "New host and port from Host field: %s = %s:%d",
3053 csp->http->hostport, csp->http->host, csp->http->port);
3056 /* Signal client_host_adder() to return right away */
3057 csp->flags |= CSP_FLAG_HOST_HEADER_IS_SET;
3063 /*********************************************************************
3065 * Function : client_if_modified_since
3067 * Description : Remove or modify the If-Modified-Since header.
3070 * 1 : csp = Current client state (buffers, headers, etc...)
3071 * 2 : header = On input, pointer to header to modify.
3072 * On output, pointer to the modified header, or NULL
3073 * to remove the header. This function frees the
3074 * original string if necessary.
3076 * Returns : JB_ERR_OK on success, or
3077 * JB_ERR_MEMORY on out-of-memory error.
3079 *********************************************************************/
3080 static jb_err client_if_modified_since(struct client_state *csp, char **header)
3083 #ifdef HAVE_GMTIME_R
3086 struct tm *timeptr = NULL;
3089 long int hours, minutes, seconds;
3092 if ( 0 == strcmpic(*header, "If-Modified-Since: Wed, 08 Jun 1955 12:00:00 GMT"))
3095 * The client got an error message because of a temporary problem,
3096 * the problem is gone and the client now tries to revalidate our
3097 * error message on the real server. The revalidation would always
3098 * end with the transmission of the whole document and there is
3099 * no need to expose the bogus If-Modified-Since header.
3101 log_error(LOG_LEVEL_HEADER, "Crunching useless If-Modified-Since header.");
3104 else if (csp->action->flags & ACTION_HIDE_IF_MODIFIED_SINCE)
3106 newval = csp->action->string[ACTION_STRING_IF_MODIFIED_SINCE];
3108 if ((0 == strcmpic(newval, "block")))
3110 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3113 else /* add random value */
3115 const char *header_time = *header + sizeof("If-Modified-Since:");
3117 if (JB_ERR_OK != parse_header_time(header_time, &tm))
3119 log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
3124 long int rtime = strtol(newval, &endptr, 0);
3125 const int negative_range = (rtime < 0);
3129 log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %d minut%s)",
3130 *header, rtime, (rtime == 1 || rtime == -1) ? "e": "es");
3136 rtime = pick_from_range(rtime);
3140 log_error(LOG_LEVEL_ERROR, "Random range is 0. Assuming time transformation test.",
3143 tm += rtime * (negative_range ? -1 : 1);
3144 #ifdef HAVE_GMTIME_R
3145 timeptr = gmtime_r(&tm, &gmt);
3146 #elif defined(MUTEX_LOCKS_AVAILABLE)
3147 privoxy_mutex_lock(&gmtime_mutex);
3148 timeptr = gmtime(&tm);
3149 privoxy_mutex_unlock(&gmtime_mutex);
3151 timeptr = gmtime(&tm);
3153 if ((NULL == timeptr) || !strftime(newheader,
3154 sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
3156 log_error(LOG_LEVEL_ERROR,
3157 "Randomizing '%s' failed. Crunching the header without replacement.",
3164 *header = strdup("If-Modified-Since: ");
3165 string_append(header, newheader);
3167 if (*header == NULL)
3169 log_error(LOG_LEVEL_HEADER, "Insufficient memory, header crunched without replacement.");
3170 return JB_ERR_MEMORY;
3173 hours = rtime / 3600;
3174 minutes = rtime / 60 % 60;
3175 seconds = rtime % 60;
3177 log_error(LOG_LEVEL_HEADER,
3178 "Randomized: %s (%s %d hou%s %d minut%s %d second%s",
3179 *header, (negative_range) ? "subtracted" : "added", hours,
3180 (hours == 1) ? "r" : "rs", minutes, (minutes == 1) ? "e" : "es",
3181 seconds, (seconds == 1) ? ")" : "s)");
3190 /*********************************************************************
3192 * Function : client_if_none_match
3194 * Description : Remove the If-None-Match header.
3197 * 1 : csp = Current client state (buffers, headers, etc...)
3198 * 2 : header = On input, pointer to header to modify.
3199 * On output, pointer to the modified header, or NULL
3200 * to remove the header. This function frees the
3201 * original string if necessary.
3203 * Returns : JB_ERR_OK on success, or
3204 * JB_ERR_MEMORY on out-of-memory error.
3206 *********************************************************************/
3207 static jb_err client_if_none_match(struct client_state *csp, char **header)
3209 if (csp->action->flags & ACTION_CRUNCH_IF_NONE_MATCH)
3211 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3219 /*********************************************************************
3221 * Function : client_x_filter
3223 * Description : Disables filtering if the client set "X-Filter: No".
3224 * Called from `sed'.
3227 * 1 : csp = Current client state (buffers, headers, etc...)
3228 * 2 : header = On input, pointer to header to modify.
3229 * On output, pointer to the modified header, or NULL
3230 * to remove the header. This function frees the
3231 * original string if necessary.
3233 * Returns : JB_ERR_OK on success
3235 *********************************************************************/
3236 jb_err client_x_filter(struct client_state *csp, char **header)
3238 if ( 0 == strcmpic(*header, "X-Filter: No"))
3240 if (!(csp->config->feature_flags & RUNTIME_FEATURE_HTTP_TOGGLE))
3242 log_error(LOG_LEVEL_INFO, "Ignored the client's request to fetch without filtering.");
3246 if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
3248 log_error(LOG_LEVEL_HEADER,
3249 "force-text-mode overruled the client's request to fetch without filtering!");
3253 csp->content_type = CT_TABOO; /* XXX: This hack shouldn't be necessary */
3254 csp->flags |= CSP_FLAG_NO_FILTERING;
3255 log_error(LOG_LEVEL_HEADER, "Accepted the client's request to fetch without filtering.");
3257 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3265 /*********************************************************************
3267 * Function : client_range
3269 * Description : Removes Range, Request-Range and If-Range headers if
3270 * content filtering is enabled. If the client's version
3271 * of the document has been altered by Privoxy, the server
3272 * could interpret the range differently than the client
3273 * intended in which case the user could end up with
3274 * corrupted content.
3277 * 1 : csp = Current client state (buffers, headers, etc...)
3278 * 2 : header = On input, pointer to header to modify.
3279 * On output, pointer to the modified header, or NULL
3280 * to remove the header. This function frees the
3281 * original string if necessary.
3283 * Returns : JB_ERR_OK
3285 *********************************************************************/
3286 static jb_err client_range(struct client_state *csp, char **header)
3288 if (content_filters_enabled(csp->action))
3290 log_error(LOG_LEVEL_HEADER, "Content filtering is enabled."
3291 " Crunching: \'%s\' to prevent range-mismatch problems.", *header);
3298 /* the following functions add headers directly to the header list */
3300 /*********************************************************************
3302 * Function : client_host_adder
3304 * Description : Adds the Host: header field if it is missing.
3305 * Called from `sed'.
3308 * 1 : csp = Current client state (buffers, headers, etc...)
3310 * Returns : JB_ERR_OK on success, or
3311 * JB_ERR_MEMORY on out-of-memory error.
3313 *********************************************************************/
3314 static jb_err client_host_adder(struct client_state *csp)
3319 if (csp->flags & CSP_FLAG_HOST_HEADER_IS_SET)
3321 /* Header already set by the client, nothing to do. */
3325 if ( !csp->http->hostport || !*(csp->http->hostport))
3327 /* XXX: When does this happen and why is it OK? */
3328 log_error(LOG_LEVEL_INFO, "Weirdness in client_host_adder detected and ignored.");
3333 * remove 'user:pass@' from 'proto://user:pass@host'
3335 if ( (p = strchr( csp->http->hostport, '@')) != NULL )
3341 p = csp->http->hostport;
3344 /* XXX: Just add it, we already made sure that it will be unique */
3345 log_error(LOG_LEVEL_HEADER, "addh-unique: Host: %s", p);
3346 err = enlist_unique_header(csp->headers, "Host", p);
3353 /*********************************************************************
3355 * Function : client_accept_encoding_adder
3357 * Description : Add an Accept-Encoding header to the client's request
3358 * that disables compression if the action applies, and
3359 * the header is not already there. Called from `sed'.
3360 * Note: For HTTP/1.0, the absence of the header is enough.
3363 * 1 : csp = Current client state (buffers, headers, etc...)
3365 * Returns : JB_ERR_OK on success, or
3366 * JB_ERR_MEMORY on out-of-memory error.
3368 *********************************************************************/
3369 static jb_err client_accept_encoding_adder(struct client_state *csp)
3371 if ( ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
3372 && (!strcmpic(csp->http->ver, "HTTP/1.1")) )
3374 return enlist_unique(csp->headers, "Accept-Encoding: identity;q=1.0, *;q=0", 16);
3382 /*********************************************************************
3384 * Function : client_xtra_adder
3386 * Description : Used in the add_client_headers list. Called from `sed'.
3389 * 1 : csp = Current client state (buffers, headers, etc...)
3391 * Returns : JB_ERR_OK on success, or
3392 * JB_ERR_MEMORY on out-of-memory error.
3394 *********************************************************************/
3395 static jb_err client_xtra_adder(struct client_state *csp)
3397 struct list_entry *lst;
3400 for (lst = csp->action->multi[ACTION_MULTI_ADD_HEADER]->first;
3401 lst ; lst = lst->next)
3403 log_error(LOG_LEVEL_HEADER, "addh: %s", lst->str);
3404 err = enlist(csp->headers, lst->str);
3416 /*********************************************************************
3418 * Function : client_x_forwarded_for_adder
3420 * Description : Used in the add_client_headers list. Called from `sed'.
3423 * 1 : csp = Current client state (buffers, headers, etc...)
3425 * Returns : JB_ERR_OK on success, or
3426 * JB_ERR_MEMORY on out-of-memory error.
3428 *********************************************************************/
3429 static jb_err client_x_forwarded_for_adder(struct client_state *csp)
3431 char *header = NULL;
3434 if (!((csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR)
3435 && (0 == strcmpic(csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR], "add")))
3436 || (csp->flags & CSP_FLAG_X_FORWARDED_FOR_APPENDED))
3439 * If we aren't adding X-Forwarded-For headers,
3440 * or we already appended an existing X-Forwarded-For
3441 * header, there's nothing left to do here.
3446 header = strdup("X-Forwarded-For: ");
3447 string_append(&header, csp->ip_addr_str);
3451 return JB_ERR_MEMORY;
3454 log_error(LOG_LEVEL_HEADER, "addh: %s", header);
3455 err = enlist(csp->headers, header);
3462 /*********************************************************************
3464 * Function : server_connection_adder
3466 * Description : Adds an appropiate "Connection:" header to csp->headers
3467 * unless the header was already present. Called from `sed'.
3470 * 1 : csp = Current client state (buffers, headers, etc...)
3472 * Returns : JB_ERR_OK on success, or
3473 * JB_ERR_MEMORY on out-of-memory error.
3475 *********************************************************************/
3476 static jb_err server_connection_adder(struct client_state *csp)
3478 const unsigned int flags = csp->flags;
3479 const char *response_status_line = csp->headers->first->str;
3480 static const char connection_close[] = "Connection: close";
3482 if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
3483 && (flags & CSP_FLAG_SERVER_CONNECTION_HEADER_SET))
3489 * XXX: if we downgraded the response, this check will fail.
3491 if ((csp->config->feature_flags &
3492 RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
3493 && (NULL != response_status_line)
3494 && !strncmpic(response_status_line, "HTTP/1.1", 8)
3495 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3496 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
3500 log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
3501 "without Connection header implies keep-alive.");
3502 csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
3506 log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
3508 return enlist(csp->headers, connection_close);
3512 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3513 /*********************************************************************
3515 * Function : server_proxy_connection_adder
3517 * Description : Adds a "Proxy-Connection: keep-alive" header to
3518 * csp->headers if the client asked for keep-alive.
3519 * XXX: We should reuse existant ones.
3522 * 1 : csp = Current client state (buffers, headers, etc...)
3524 * Returns : JB_ERR_OK on success, or
3525 * JB_ERR_MEMORY on out-of-memory error.
3527 *********************************************************************/
3528 static jb_err server_proxy_connection_adder(struct client_state *csp)
3530 static const char proxy_connection_header[] = "Proxy-Connection: keep-alive";
3531 jb_err err = JB_ERR_OK;
3533 if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
3534 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
3536 log_error(LOG_LEVEL_HEADER, "Adding: %s", proxy_connection_header);
3537 err = enlist(csp->headers, proxy_connection_header);
3542 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
3545 /*********************************************************************
3547 * Function : client_connection_header_adder
3549 * Description : Adds a proper "Connection:" header to csp->headers
3550 * unless the header was already present. Called from `sed'.
3553 * 1 : csp = Current client state (buffers, headers, etc...)
3555 * Returns : JB_ERR_OK on success, or
3556 * JB_ERR_MEMORY on out-of-memory error.
3558 *********************************************************************/
3559 static jb_err client_connection_header_adder(struct client_state *csp)
3561 static const char connection_close[] = "Connection: close";
3563 if (!(csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
3564 && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET))
3569 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3570 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
3571 && (csp->http->ssl == 0)
3572 && !strcmpic(csp->http->ver, "HTTP/1.1"))
3574 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
3577 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
3579 log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
3581 return enlist(csp->headers, connection_close);
3585 /*********************************************************************
3587 * Function : server_http
3589 * Description : - Save the HTTP Status into csp->http->status
3590 * - Set CT_TABOO to prevent filtering if the answer
3591 * is a partial range (HTTP status 206)
3592 * - Rewrite HTTP/1.1 answers to HTTP/1.0 if +downgrade
3596 * 1 : csp = Current client state (buffers, headers, etc...)
3597 * 2 : header = On input, pointer to header to modify.
3598 * On output, pointer to the modified header, or NULL
3599 * to remove the header. This function frees the
3600 * original string if necessary.
3602 * Returns : JB_ERR_OK on success, or
3603 * JB_ERR_MEMORY on out-of-memory error.
3605 *********************************************************************/
3606 static jb_err server_http(struct client_state *csp, char **header)
3608 sscanf(*header, "HTTP/%*d.%*d %d", &(csp->http->status));
3609 if (csp->http->status == 206)
3611 csp->content_type = CT_TABOO;
3614 if ((csp->action->flags & ACTION_DOWNGRADE) != 0)
3616 /* XXX: Should we do a real validity check here? */
3617 if (strlen(*header) > 8)
3620 log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0");
3625 * XXX: Should we block the request or
3626 * enlist a valid status code line here?
3628 log_error(LOG_LEVEL_INFO, "Malformed server response detected. "
3629 "Downgrading to HTTP/1.0 impossible.");
3637 /*********************************************************************
3639 * Function : server_set_cookie
3641 * Description : Handle the server "cookie" header properly.
3642 * Log cookie to the jar file. Then "crunch",
3643 * accept or rewrite it to a session cookie.
3644 * Called from `sed'.
3646 * TODO: Allow the user to specify a new expiration
3647 * time to cause the cookie to expire even before the
3648 * browser is closed.
3651 * 1 : csp = Current client state (buffers, headers, etc...)
3652 * 2 : header = On input, pointer to header to modify.
3653 * On output, pointer to the modified header, or NULL
3654 * to remove the header. This function frees the
3655 * original string if necessary.
3657 * Returns : JB_ERR_OK on success, or
3658 * JB_ERR_MEMORY on out-of-memory error.
3660 *********************************************************************/
3661 static jb_err server_set_cookie(struct client_state *csp, char **header)
3668 if ((csp->action->flags & ACTION_NO_COOKIE_SET) != 0)
3670 log_error(LOG_LEVEL_HEADER, "Crunching incoming cookie: %s", *header);
3673 else if ((csp->action->flags & ACTION_NO_COOKIE_KEEP) != 0)
3675 /* Flag whether or not to log a message */
3678 /* A variable to store the tag we're working on */
3681 /* Skip "Set-Cookie:" (11 characters) in header */
3682 cur_tag = *header + 11;
3684 /* skip whitespace between "Set-Cookie:" and value */
3685 while (*cur_tag && ijb_isspace(*cur_tag))
3690 /* Loop through each tag in the cookie */
3694 char *next_tag = strchr(cur_tag, ';');
3695 if (next_tag != NULL)
3697 /* Skip the ';' character itself */
3700 /* skip whitespace ";" and start of tag */
3701 while (*next_tag && ijb_isspace(*next_tag))
3708 /* "Next tag" is the end of the string */
3709 next_tag = cur_tag + strlen(cur_tag);
3713 * Check the expiration date to see
3714 * if the cookie is still valid, if yes,
3715 * rewrite it to a session cookie.
3717 if ((strncmpic(cur_tag, "expires=", 8) == 0) && *(cur_tag + 8))
3719 char *expiration_date = cur_tag + 8; /* Skip "[Ee]xpires=" */
3721 /* Did we detect the date properly? */
3722 if (JB_ERR_OK != parse_header_time(expiration_date, &cookie_time))
3725 * Nope, treat it as if it was still valid.
3727 * XXX: Should we remove the whole cookie instead?
3729 log_error(LOG_LEVEL_ERROR,
3730 "Can't parse \'%s\', send by %s. Unsupported time format?", cur_tag, csp->http->url);
3731 string_move(cur_tag, next_tag);
3737 * Yes. Check if the cookie is still valid.
3739 * If the cookie is already expired it's probably
3740 * a delete cookie and even if it isn't, the browser
3741 * will discard it anyway.
3745 * XXX: timegm() isn't available on some AmigaOS
3746 * versions and our replacement doesn't work.
3748 * Our options are to either:
3750 * - disable session-cookies-only completely if timegm
3753 * - to simply remove all expired tags, like it has
3754 * been done until Privoxy 3.0.6 and to live with
3755 * the consequence that it can cause login/logout
3756 * problems on servers that don't validate their
3757 * input properly, or
3759 * - to replace it with mktime in which
3760 * case there is a slight chance of valid cookies
3761 * passing as already expired.
3763 * This is the way it's currently done and it's not
3764 * as bad as it sounds. If the missing GMT offset is
3765 * enough to change the result of the expiration check
3766 * the cookie will be only valid for a few hours
3767 * anyway, which in many cases will be shorter
3768 * than a browser session.
3770 if (cookie_time - now < 0)
3772 log_error(LOG_LEVEL_HEADER,
3773 "Cookie \'%s\' is already expired and can pass unmodified.", *header);
3774 /* Just in case some clown sets more then one expiration date */
3780 * Still valid, delete expiration date by copying
3781 * the rest of the string over it.
3783 string_move(cur_tag, next_tag);
3785 /* That changed the header, need to issue a log message */
3789 * Note that the next tag has now been moved to *cur_tag,
3790 * so we do not need to update the cur_tag pointer.
3798 /* Move on to next cookie tag */
3805 assert(NULL != *header);
3806 log_error(LOG_LEVEL_HEADER, "Cookie rewritten to a temporary one: %s",
3815 #ifdef FEATURE_FORCE_LOAD
3816 /*********************************************************************
3818 * Function : strclean
3820 * Description : In-Situ-Eliminate all occurances of substring in
3824 * 1 : string = string to clean
3825 * 2 : substring = substring to eliminate
3827 * Returns : Number of eliminations
3829 *********************************************************************/
3830 int strclean(char *string, const char *substring)
3836 len = strlen(substring);
3838 while((pos = strstr(string, substring)) != NULL)
3845 while (*p++ != '\0');
3852 #endif /* def FEATURE_FORCE_LOAD */
3855 /*********************************************************************
3857 * Function : parse_header_time
3859 * Description : Parses time formats used in HTTP header strings
3860 * to get the numerical respresentation.
3863 * 1 : header_time = HTTP header time as string.
3864 * 2 : result = storage for header_time in seconds
3866 * Returns : JB_ERR_OK if the time format was recognized, or
3867 * JB_ERR_PARSE otherwise.
3869 *********************************************************************/
3870 static jb_err parse_header_time(const char *header_time, time_t *result)
3875 * Zero out gmt to prevent time zone offsets.
3877 * While this is only necessary on some platforms
3878 * (mingw32 for example), I don't know how to
3879 * detect these automatically and doing it everywhere
3882 memset(&gmt, 0, sizeof(gmt));
3884 /* Tue, 02 Jun 2037 20:00:00 */
3885 if ((NULL == strptime(header_time, "%a, %d %b %Y %H:%M:%S", &gmt))
3886 /* Tue, 02-Jun-2037 20:00:00 */
3887 && (NULL == strptime(header_time, "%a, %d-%b-%Y %H:%M:%S", &gmt))
3888 /* Tue, 02-Jun-37 20:00:00 */
3889 && (NULL == strptime(header_time, "%a, %d-%b-%y %H:%M:%S", &gmt))
3890 /* Tuesday, 02-Jun-2037 20:00:00 */
3891 && (NULL == strptime(header_time, "%A, %d-%b-%Y %H:%M:%S", &gmt))
3892 /* Tuesday Jun 02 20:00:00 2037 */
3893 && (NULL == strptime(header_time, "%A %b %d %H:%M:%S %Y", &gmt)))
3895 return JB_ERR_PARSE;
3898 *result = timegm(&gmt);
3905 /*********************************************************************
3907 * Function : get_destination_from_headers
3909 * Description : Parse the "Host:" header to get the request's destination.
3910 * Only needed if the client's request was forcefully
3911 * redirected into Privoxy.
3913 * Code mainly copied from client_host() which is currently
3914 * run too late for this purpose.
3917 * 1 : headers = List of headers (one of them hopefully being
3918 * the "Host:" header)
3919 * 2 : http = storage for the result (host, port and hostport).
3921 * Returns : JB_ERR_MEMORY in case of memory problems,
3922 * JB_ERR_PARSE if the host header couldn't be found,
3923 * JB_ERR_OK otherwise.
3925 *********************************************************************/
3926 jb_err get_destination_from_headers(const struct list *headers, struct http_request *http)
3932 host = get_header_value(headers, "Host:");
3936 log_error(LOG_LEVEL_ERROR, "No \"Host:\" header found.");
3937 return JB_ERR_PARSE;
3940 if (NULL == (p = strdup((host))))
3942 log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
3943 return JB_ERR_MEMORY;
3946 if (NULL == (q = strdup(p)))
3949 log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
3950 return JB_ERR_MEMORY;
3953 freez(http->hostport);
3957 q = strchr(http->host, ':');
3960 /* Terminate hostname and evaluate port string */
3962 http->port = atoi(q);
3966 http->port = http->ssl ? 443 : 80;
3969 /* Rebuild request URL */
3971 http->url = strdup(http->ssl ? "https://" : "http://");
3972 string_append(&http->url, http->hostport);
3973 string_append(&http->url, http->path);
3974 if (http->url == NULL)
3976 return JB_ERR_MEMORY;
3979 log_error(LOG_LEVEL_HEADER, "Destination extracted from \"Host:\" header. New request URL: %s",
3987 /*********************************************************************
3989 * Function : create_forged_referrer
3991 * Description : Helper for client_referrer to forge a referer as
3992 * 'http://[hostname:port/' to fool stupid
3993 * checks for in-site links
3996 * 1 : header = Pointer to header pointer
3997 * 2 : hostport = Host and optionally port as string
3999 * Returns : JB_ERR_OK in case of success, or
4000 * JB_ERR_MEMORY in case of memory problems.
4002 *********************************************************************/
4003 static jb_err create_forged_referrer(char **header, const char *hostport)
4005 assert(NULL == *header);
4007 *header = strdup("Referer: http://");
4008 string_append(header, hostport);
4009 string_append(header, "/");
4011 if (NULL == *header)
4013 return JB_ERR_MEMORY;
4016 log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
4023 /*********************************************************************
4025 * Function : create_fake_referrer
4027 * Description : Helper for client_referrer to create a fake referrer
4028 * based on a string supplied by the user.
4031 * 1 : header = Pointer to header pointer
4032 * 2 : hosthost = Referrer to fake
4034 * Returns : JB_ERR_OK in case of success, or
4035 * JB_ERR_MEMORY in case of memory problems.
4037 *********************************************************************/
4038 static jb_err create_fake_referrer(char **header, const char *fake_referrer)
4040 assert(NULL == *header);
4042 if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
4044 log_error(LOG_LEVEL_HEADER,
4045 "Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
4047 *header = strdup("Referer: ");
4048 string_append(header, fake_referrer);
4050 if (NULL == *header)
4052 return JB_ERR_MEMORY;
4055 log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
4062 /*********************************************************************
4064 * Function : handle_conditional_hide_referrer_parameter
4066 * Description : Helper for client_referrer to crunch or forge
4067 * the referrer header if the host has changed.
4070 * 1 : header = Pointer to header pointer
4071 * 2 : host = The target host (may include the port)
4072 * 3 : parameter_conditional_block = Boolean to signal
4073 * if we're in conditional-block mode. If not set,
4074 * we're in conditional-forge mode.
4076 * Returns : JB_ERR_OK in case of success, or
4077 * JB_ERR_MEMORY in case of memory problems.
4079 *********************************************************************/
4080 static jb_err handle_conditional_hide_referrer_parameter(char **header,
4081 const char *host, const int parameter_conditional_block)
4083 char *referer = strdup(*header);
4084 const size_t hostlenght = strlen(host);
4085 const char *referer_url = NULL;
4087 if (NULL == referer)
4090 return JB_ERR_MEMORY;
4093 /* referer begins with 'Referer: http[s]://' */
4094 if ((hostlenght+17) < strlen(referer))
4097 * Shorten referer to make sure the referer is blocked
4098 * if www.example.org/www.example.com-shall-see-the-referer/
4099 * links to www.example.com/
4101 referer[hostlenght+17] = '\0';
4103 referer_url = strstr(referer, "http://");
4104 if ((NULL == referer_url) || (NULL == strstr(referer_url, host)))
4106 /* Host has changed, Referer is invalid or a https URL. */
4107 if (parameter_conditional_block)
4109 log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
4116 return create_forged_referrer(header, host);
4126 /*********************************************************************
4128 * Function : create_content_length_header
4130 * Description : Creates a Content-Length header.
4133 * 1 : content_length = The content length to be used in the header.
4134 * 2 : header = Allocated space to safe the header.
4135 * 3 : buffer_length = The length of the allocated space.
4139 *********************************************************************/
4140 static void create_content_length_header(unsigned long long content_length,
4141 char *header, size_t buffer_length)
4143 snprintf(header, buffer_length, "Content-Length: %llu", content_length);