1 const char parsers_rcs[] = "$Id: parsers.c,v 1.204 2009/08/19 15:25:31 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 server_proxy_connection(struct client_state *csp, char **header);
160 static jb_err client_keep_alive(struct client_state *csp, char **header);
161 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
163 static jb_err client_host_adder (struct client_state *csp);
164 static jb_err client_xtra_adder (struct client_state *csp);
165 static jb_err client_x_forwarded_for_adder(struct client_state *csp);
166 static jb_err client_connection_header_adder(struct client_state *csp);
167 static jb_err server_connection_adder(struct client_state *csp);
168 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
169 static jb_err server_proxy_connection_adder(struct client_state *csp);
170 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
172 static jb_err create_forged_referrer(char **header, const char *hostport);
173 static jb_err create_fake_referrer(char **header, const char *fake_referrer);
174 static jb_err handle_conditional_hide_referrer_parameter(char **header,
175 const char *host, const int parameter_conditional_block);
176 static void create_content_length_header(unsigned long long content_length,
177 char *header, size_t buffer_length);
180 * List of functions to run on a list of headers.
184 /** The header prefix to match */
187 /** The length of the prefix to match */
190 /** The function to apply to this line */
191 const parser_func_ptr parser;
194 static const struct parsers client_patterns[] = {
195 { "referer:", 8, client_referrer },
196 { "user-agent:", 11, client_uagent },
197 { "ua-", 3, client_ua },
198 { "from:", 5, client_from },
199 { "cookie:", 7, client_send_cookie },
200 { "x-forwarded-for:", 16, client_x_forwarded },
201 { "Accept-Encoding:", 16, client_accept_encoding },
202 { "TE:", 3, client_te },
203 { "Host:", 5, client_host },
204 { "if-modified-since:", 18, client_if_modified_since },
205 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
206 { "Keep-Alive:", 11, client_keep_alive },
208 { "Keep-Alive:", 11, crumble },
210 { "connection:", 11, client_connection },
211 { "proxy-connection:", 17, crumble },
212 { "max-forwards:", 13, client_max_forwards },
213 { "Accept-Language:", 16, client_accept_language },
214 { "if-none-match:", 14, client_if_none_match },
215 { "Range:", 6, client_range },
216 { "Request-Range:", 14, client_range },
217 { "If-Range:", 9, client_range },
218 { "X-Filter:", 9, client_x_filter },
219 { "*", 0, crunch_client_header },
220 { "*", 0, filter_header },
224 static const struct parsers server_patterns[] = {
225 { "HTTP/", 5, server_http },
226 { "set-cookie:", 11, server_set_cookie },
227 { "connection:", 11, server_connection },
228 { "Content-Type:", 13, server_content_type },
229 { "Content-MD5:", 12, server_content_md5 },
230 { "Content-Encoding:", 17, server_content_encoding },
231 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
232 { "Content-Length:", 15, server_save_content_length },
233 { "Keep-Alive:", 11, server_keep_alive },
234 { "Proxy-Connection:", 17, server_proxy_connection },
236 { "Keep-Alive:", 11, crumble },
237 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
238 { "Transfer-Encoding:", 18, server_transfer_coding },
239 { "content-disposition:", 20, server_content_disposition },
240 { "Last-Modified:", 14, server_last_modified },
241 { "*", 0, crunch_server_header },
242 { "*", 0, filter_header },
246 static const add_header_func_ptr add_client_headers[] = {
248 client_x_forwarded_for_adder,
250 /* Temporarily disabled: client_accept_encoding_adder, */
251 client_connection_header_adder,
255 static const add_header_func_ptr add_server_headers[] = {
256 server_connection_adder,
257 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
258 server_proxy_connection_adder,
259 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
263 /*********************************************************************
265 * Function : flush_socket
267 * Description : Write any pending "buffered" content.
270 * 1 : fd = file descriptor of the socket to read
271 * 2 : iob = The I/O buffer to flush, usually csp->iob.
273 * Returns : On success, the number of bytes written are returned (zero
274 * indicates nothing was written). On error, -1 is returned,
275 * and errno is set appropriately. If count is zero and the
276 * file descriptor refers to a regular file, 0 will be
277 * returned without causing any other effect. For a special
278 * file, the results are not portable.
280 *********************************************************************/
281 long flush_socket(jb_socket fd, struct iob *iob)
283 long len = iob->eod - iob->cur;
290 if (write_socket(fd, iob->cur, (size_t)len))
294 iob->eod = iob->cur = iob->buf;
300 /*********************************************************************
302 * Function : add_to_iob
304 * Description : Add content to the buffered page, expanding the
305 * buffer if necessary.
308 * 1 : csp = Current client state (buffers, headers, etc...)
309 * 2 : buf = holds the content to be added to the page
310 * 3 : n = number of bytes to be added
312 * Returns : JB_ERR_OK on success, JB_ERR_MEMORY if out-of-memory
313 * or buffer limit reached.
315 *********************************************************************/
316 jb_err add_to_iob(struct client_state *csp, char *buf, long n)
318 struct iob *iob = csp->iob;
319 size_t used, offset, need, want;
322 if (n <= 0) return JB_ERR_OK;
324 used = (size_t)(iob->eod - iob->buf);
325 offset = (size_t)(iob->cur - iob->buf);
326 need = used + (size_t)n + 1;
329 * If the buffer can't hold the new data, extend it first.
330 * Use the next power of two if possible, else use the actual need.
332 if (need > csp->config->buffer_limit)
334 log_error(LOG_LEVEL_INFO,
335 "Buffer limit reached while extending the buffer (iob). Needed: %d. Limit: %d",
336 need, csp->config->buffer_limit);
337 return JB_ERR_MEMORY;
340 if (need > iob->size)
342 for (want = csp->iob->size ? csp->iob->size : 512; want <= need;) want *= 2;
344 if (want <= csp->config->buffer_limit && NULL != (p = (char *)realloc(iob->buf, want)))
348 else if (NULL != (p = (char *)realloc(iob->buf, need)))
354 log_error(LOG_LEVEL_ERROR, "Extending the buffer (iob) failed: %E");
355 return JB_ERR_MEMORY;
358 /* Update the iob pointers */
359 iob->cur = p + offset;
364 /* copy the new data into the iob buffer */
365 memcpy(iob->eod, buf, (size_t)n);
367 /* point to the end of the data */
370 /* null terminate == cheap insurance */
379 /*********************************************************************
381 * Function : decompress_iob
383 * Description : Decompress buffered page, expanding the
384 * buffer as necessary. csp->iob->cur
385 * should point to the the beginning of the
386 * compressed data block.
389 * 1 : csp = Current client state (buffers, headers, etc...)
391 * Returns : JB_ERR_OK on success,
392 * JB_ERR_MEMORY if out-of-memory limit reached, and
393 * JB_ERR_COMPRESS if error decompressing buffer.
395 *********************************************************************/
396 jb_err decompress_iob(struct client_state *csp)
398 char *buf; /* new, uncompressed buffer */
399 char *cur; /* Current iob position (to keep the original
400 * iob->cur unmodified if we return early) */
401 size_t bufsize; /* allocated size of the new buffer */
402 size_t old_size; /* Content size before decompression */
403 size_t skip_size; /* Number of bytes at the beginning of the iob
404 that we should NOT decompress. */
405 int status; /* return status of the inflate() call */
406 z_stream zstr; /* used by calls to zlib */
408 assert(csp->iob->cur - csp->iob->buf > 0);
409 assert(csp->iob->eod - csp->iob->cur > 0);
411 bufsize = csp->iob->size;
412 skip_size = (size_t)(csp->iob->cur - csp->iob->buf);
413 old_size = (size_t)(csp->iob->eod - csp->iob->cur);
417 if (bufsize < (size_t)10)
420 * This is to protect the parsing of gzipped data,
421 * but it should(?) be valid for deflated data also.
423 log_error(LOG_LEVEL_ERROR, "Buffer too small decompressing iob");
424 return JB_ERR_COMPRESS;
427 if (csp->content_type & CT_GZIP)
430 * Our task is slightly complicated by the facts that data
431 * compressed by gzip does not include a zlib header, and
432 * that there is no easily accessible interface in zlib to
433 * handle a gzip header. We strip off the gzip header by
434 * hand, and later inform zlib not to expect a header.
438 * Strip off the gzip header. Please see RFC 1952 for more
439 * explanation of the appropriate fields.
441 if (((*cur++ & 0xff) != GZIP_IDENTIFIER_1)
442 || ((*cur++ & 0xff) != GZIP_IDENTIFIER_2)
443 || (*cur++ != Z_DEFLATED))
445 log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
446 return JB_ERR_COMPRESS;
451 if (flags & GZIP_FLAG_RESERVED_BITS)
453 /* The gzip header has reserved bits set; bail out. */
454 log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
455 return JB_ERR_COMPRESS;
459 * Skip mtime (4 bytes), extra flags (1 byte)
460 * and OS type (1 byte).
464 /* Skip extra fields if necessary. */
465 if (flags & GZIP_FLAG_EXTRA_FIELDS)
468 * Skip a given number of bytes, specified
469 * as a 16-bit little-endian value.
471 * XXX: this code is untested and should probably be removed.
475 skip_bytes += *cur++ << 8;
478 * The number of bytes to skip should be positive
479 * and we'd like to stay in the buffer.
481 if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
483 log_error(LOG_LEVEL_ERROR,
484 "Unreasonable amount of bytes to skip (%d). Stopping decompression",
486 return JB_ERR_COMPRESS;
488 log_error(LOG_LEVEL_INFO,
489 "Skipping %d bytes for gzip compression. Does this sound right?",
494 /* Skip the filename if necessary. */
495 if (flags & GZIP_FLAG_FILE_NAME)
497 /* A null-terminated string is supposed to follow. */
498 while (*cur++ && (cur < csp->iob->eod));
501 /* Skip the comment if necessary. */
502 if (flags & GZIP_FLAG_COMMENT)
504 /* A null-terminated string is supposed to follow. */
505 while (*cur++ && (cur < csp->iob->eod));
508 /* Skip the CRC if necessary. */
509 if (flags & GZIP_FLAG_CHECKSUM)
514 if (cur >= csp->iob->eod)
517 * If the current position pointer reached or passed
518 * the buffer end, we were obviously tricked to skip
521 log_error(LOG_LEVEL_ERROR,
522 "Malformed gzip header detected. Aborting decompression.");
523 return JB_ERR_COMPRESS;
527 else if (csp->content_type & CT_DEFLATE)
530 * XXX: The debug level should be lowered
531 * before the next stable release.
533 log_error(LOG_LEVEL_INFO, "Decompressing deflated iob: %d", *cur);
535 * In theory (that is, according to RFC 1950), deflate-compressed
536 * data should begin with a two-byte zlib header and have an
537 * adler32 checksum at the end. It seems that in practice only
538 * the raw compressed data is sent. Note that this means that
539 * we are not RFC 1950-compliant here, but the advantage is that
540 * this actually works. :)
542 * We add a dummy null byte to tell zlib where the data ends,
543 * and later inform it not to expect a header.
545 * Fortunately, add_to_iob() has thoughtfully null-terminated
546 * the buffer; we can just increment the end pointer to include
553 log_error(LOG_LEVEL_ERROR,
554 "Unable to determine compression format for decompression");
555 return JB_ERR_COMPRESS;
558 /* Set up the fields required by zlib. */
559 zstr.next_in = (Bytef *)cur;
560 zstr.avail_in = (unsigned int)(csp->iob->eod - cur);
561 zstr.zalloc = Z_NULL;
563 zstr.opaque = Z_NULL;
566 * Passing -MAX_WBITS to inflateInit2 tells the library
567 * that there is no zlib header.
569 if (inflateInit2(&zstr, -MAX_WBITS) != Z_OK)
571 log_error(LOG_LEVEL_ERROR, "Error initializing decompression");
572 return JB_ERR_COMPRESS;
576 * Next, we allocate new storage for the inflated data.
577 * We don't modify the existing iob yet, so in case there
578 * is error in decompression we can recover gracefully.
580 buf = zalloc(bufsize);
583 log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
584 return JB_ERR_MEMORY;
587 assert(bufsize >= skip_size);
588 memcpy(buf, csp->iob->buf, skip_size);
589 zstr.avail_out = (uInt)(bufsize - skip_size);
590 zstr.next_out = (Bytef *)buf + skip_size;
592 /* Try to decompress the whole stream in one shot. */
593 while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH)))
595 /* We need to allocate more memory for the output buffer. */
597 char *tmpbuf; /* used for realloc'ing the buffer */
598 size_t oldbufsize = bufsize; /* keep track of the old bufsize */
600 if (0 == zstr.avail_in)
603 * If zlib wants more data then there's a problem, because
604 * the complete compressed file should have been buffered.
606 log_error(LOG_LEVEL_ERROR,
607 "Unexpected end of compressed iob. Using what we got so far.");
612 * If we tried the limit and still didn't have enough
613 * memory, just give up.
615 if (bufsize == csp->config->buffer_limit)
617 log_error(LOG_LEVEL_ERROR, "Buffer limit reached while decompressing iob");
618 return JB_ERR_MEMORY;
621 /* Try doubling the buffer size each time. */
624 /* Don't exceed the buffer limit. */
625 if (bufsize > csp->config->buffer_limit)
627 bufsize = csp->config->buffer_limit;
630 /* Try to allocate the new buffer. */
631 tmpbuf = realloc(buf, bufsize);
634 log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
636 return JB_ERR_MEMORY;
640 char *oldnext_out = (char *)zstr.next_out;
643 * Update the fields for inflate() to use the new
644 * buffer, which may be in a location different from
647 zstr.avail_out += (uInt)(bufsize - oldbufsize);
648 zstr.next_out = (Bytef *)tmpbuf + bufsize - zstr.avail_out;
651 * Compare with an uglier method of calculating these values
652 * that doesn't require the extra oldbufsize variable.
654 assert(zstr.avail_out == tmpbuf + bufsize - (char *)zstr.next_out);
655 assert((char *)zstr.next_out == tmpbuf + ((char *)oldnext_out - buf));
661 if (Z_STREAM_ERROR == inflateEnd(&zstr))
663 log_error(LOG_LEVEL_ERROR,
664 "Inconsistent stream state after decompression: %s", zstr.msg);
666 * XXX: Intentionally no return.
668 * According to zlib.h, Z_STREAM_ERROR is returned
669 * "if the stream state was inconsistent".
671 * I assume in this case inflate()'s status
672 * would also be something different than Z_STREAM_END
673 * so this check should be redundant, but lets see.
677 if ((status != Z_STREAM_END) && (0 != zstr.avail_in))
680 * We failed to decompress the stream and it's
681 * not simply because of missing data.
683 log_error(LOG_LEVEL_ERROR,
684 "Unexpected error while decompressing to the buffer (iob): %s",
686 return JB_ERR_COMPRESS;
690 * Finally, we can actually update the iob, since the
691 * decompression was successful. First, free the old
694 freez(csp->iob->buf);
696 /* Now, update the iob to use the new buffer. */
698 csp->iob->cur = csp->iob->buf + skip_size;
699 csp->iob->eod = (char *)zstr.next_out;
700 csp->iob->size = bufsize;
703 * Make sure the new uncompressed iob obeys some minimal
704 * consistency conditions.
706 if ((csp->iob->buf < csp->iob->cur)
707 && (csp->iob->cur <= csp->iob->eod)
708 && (csp->iob->eod <= csp->iob->buf + csp->iob->size))
710 const size_t new_size = (size_t)(csp->iob->eod - csp->iob->cur);
711 if (new_size > (size_t)0)
713 log_error(LOG_LEVEL_RE_FILTER,
714 "Decompression successful. Old size: %d, new size: %d.",
719 /* zlib thinks this is OK, so lets do the same. */
720 log_error(LOG_LEVEL_INFO, "Decompression didn't result in any content.");
725 /* It seems that zlib did something weird. */
726 log_error(LOG_LEVEL_ERROR,
727 "Unexpected error decompressing the buffer (iob): %d==%d, %d>%d, %d<%d",
728 csp->iob->cur, csp->iob->buf + skip_size, csp->iob->eod, csp->iob->buf,
729 csp->iob->eod, csp->iob->buf + csp->iob->size);
730 return JB_ERR_COMPRESS;
736 #endif /* defined(FEATURE_ZLIB) */
739 /*********************************************************************
741 * Function : string_move
743 * Description : memmove wrapper to move the last part of a string
744 * towards the beginning, overwriting the part in
745 * the middle. strlcpy() can't be used here as the
749 * 1 : dst = Destination to overwrite
750 * 2 : src = Source to move.
754 *********************************************************************/
755 static void string_move(char *dst, char *src)
759 /* +1 to copy the terminating nul as well. */
760 memmove(dst, src, strlen(src)+1);
764 /*********************************************************************
766 * Function : normalize_lws
768 * Description : Reduces unquoted linear white space in headers
769 * to a single space in accordance with RFC 2616 2.2.
770 * This simplifies parsing and filtering later on.
772 * XXX: Remove log messages before
773 * the next stable release?
776 * 1 : header = A header with linear white space to reduce.
780 *********************************************************************/
781 static void normalize_lws(char *header)
787 if (ijb_isspace(*p) && ijb_isspace(*(p+1)))
791 while (ijb_isspace(*q))
795 log_error(LOG_LEVEL_HEADER, "Reducing white space in '%s'", header);
801 log_error(LOG_LEVEL_HEADER,
802 "Converting tab to space in '%s'", header);
807 char *end_of_token = strstr(p+1, "\"");
809 if (NULL != end_of_token)
811 /* Don't mess with quoted text. */
816 log_error(LOG_LEVEL_HEADER,
817 "Ignoring single quote in '%s'", header);
823 p = strchr(header, ':');
824 if ((p != NULL) && (p != header) && ijb_isspace(*(p-1)))
827 * There's still space before the colon.
835 /*********************************************************************
837 * Function : get_header
839 * Description : This (odd) routine will parse the csp->iob
840 * to get the next complete header.
843 * 1 : iob = The I/O buffer to parse, usually csp->iob.
845 * Returns : Any one of the following:
847 * 1) a pointer to a dynamically allocated string that contains a header line
848 * 2) NULL indicating that the end of the header was reached
849 * 3) "" indicating that the end of the iob was reached before finding
850 * a complete header line.
852 *********************************************************************/
853 char *get_header(struct iob *iob)
857 header = get_header_line(iob);
859 if ((header == NULL) || (*header == '\0'))
862 * No complete header read yet, tell the client.
867 while ((iob->cur[0] == ' ') || (iob->cur[0] == '\t'))
870 * Header spans multiple lines, append the next one.
872 char *continued_header;
874 continued_header = get_header_line(iob);
875 if ((continued_header == NULL) || (*continued_header == '\0'))
878 * No complete header read yet, return what we got.
879 * XXX: Should "unread" header instead.
881 log_error(LOG_LEVEL_INFO,
882 "Failed to read a multi-line header properly: '%s'",
887 if (JB_ERR_OK != string_join(&header, continued_header))
889 log_error(LOG_LEVEL_FATAL,
890 "Out of memory while appending multiple headers.");
894 /* XXX: remove before next stable release. */
895 log_error(LOG_LEVEL_HEADER,
896 "Merged multiple header lines to: '%s'",
901 normalize_lws(header);
908 /*********************************************************************
910 * Function : get_header_line
912 * Description : This (odd) routine will parse the csp->iob
913 * to get the next header line.
916 * 1 : iob = The I/O buffer to parse, usually csp->iob.
918 * Returns : Any one of the following:
920 * 1) a pointer to a dynamically allocated string that contains a header line
921 * 2) NULL indicating that the end of the header was reached
922 * 3) "" indicating that the end of the iob was reached before finding
923 * a complete header line.
925 *********************************************************************/
926 static char *get_header_line(struct iob *iob)
930 if ((iob->cur == NULL)
931 || ((p = strchr(iob->cur, '\n')) == NULL))
933 return(""); /* couldn't find a complete header */
938 ret = strdup(iob->cur);
941 /* FIXME No way to handle error properly */
942 log_error(LOG_LEVEL_FATAL, "Out of memory in get_header_line()");
948 if ((q = strchr(ret, '\r')) != NULL) *q = '\0';
950 /* is this a blank line (i.e. the end of the header) ? */
962 /*********************************************************************
964 * Function : get_header_value
966 * Description : Get the value of a given header from a chained list
967 * of header lines or return NULL if no such header is
968 * present in the list.
971 * 1 : header_list = pointer to list
972 * 2 : header_name = string with name of header to look for.
973 * Trailing colon required, capitalization
976 * Returns : NULL if not found, else value of header
978 *********************************************************************/
979 char *get_header_value(const struct list *header_list, const char *header_name)
981 struct list_entry *cur_entry;
987 length = strlen(header_name);
989 for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next)
993 if (!strncmpic(cur_entry->str, header_name, length))
996 * Found: return pointer to start of value
998 ret = cur_entry->str + length;
999 while (*ret && ijb_isspace(*ret)) ret++;
1013 /*********************************************************************
1015 * Function : scan_headers
1017 * Description : Scans headers, applies tags and updates action bits.
1020 * 1 : csp = Current client state (buffers, headers, etc...)
1022 * Returns : JB_ERR_OK
1024 *********************************************************************/
1025 static jb_err scan_headers(struct client_state *csp)
1027 struct list_entry *h; /* Header */
1028 jb_err err = JB_ERR_OK;
1030 for (h = csp->headers->first; (err == JB_ERR_OK) && (h != NULL) ; h = h->next)
1032 /* Header crunch()ed in previous run? -> ignore */
1033 if (h->str == NULL) continue;
1034 log_error(LOG_LEVEL_HEADER, "scan: %s", h->str);
1035 err = header_tagger(csp, h->str);
1042 /*********************************************************************
1046 * Description : add, delete or modify lines in the HTTP header streams.
1047 * On entry, it receives a linked list of headers space
1048 * that was allocated dynamically (both the list nodes
1049 * and the header contents).
1051 * As a side effect it frees the space used by the original
1055 * 1 : csp = Current client state (buffers, headers, etc...)
1056 * 2 : filter_server_headers = Boolean to switch between
1057 * server and header filtering.
1059 * Returns : JB_ERR_OK in case off success, or
1060 * JB_ERR_MEMORY on out-of-memory error.
1062 *********************************************************************/
1063 jb_err sed(struct client_state *csp, int filter_server_headers)
1065 /* XXX: use more descriptive names. */
1066 struct list_entry *p;
1067 const struct parsers *v;
1068 const add_header_func_ptr *f;
1069 jb_err err = JB_ERR_OK;
1071 if (filter_server_headers)
1073 v = server_patterns;
1074 f = add_server_headers;
1078 v = client_patterns;
1079 f = add_client_headers;
1084 while ((err == JB_ERR_OK) && (v->str != NULL))
1086 for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
1088 /* Header crunch()ed in previous run? -> ignore */
1089 if (p->str == NULL) continue;
1091 /* Does the current parser handle this header? */
1092 if ((strncmpic(p->str, v->str, v->len) == 0) ||
1093 (v->len == CHECK_EVERY_HEADER_REMAINING))
1095 err = v->parser(csp, &(p->str));
1101 /* place additional headers on the csp->headers list */
1102 while ((err == JB_ERR_OK) && (*f))
1112 /*********************************************************************
1114 * Function : update_server_headers
1116 * Description : Updates server headers after the body has been modified.
1119 * 1 : csp = Current client state (buffers, headers, etc...)
1121 * Returns : JB_ERR_OK in case off success, or
1122 * JB_ERR_MEMORY on out-of-memory error.
1124 *********************************************************************/
1125 jb_err update_server_headers(struct client_state *csp)
1127 jb_err err = JB_ERR_OK;
1129 static const struct parsers server_patterns_light[] = {
1130 { "Content-Length:", 15, server_adjust_content_length },
1131 { "Transfer-Encoding:", 18, server_transfer_coding },
1133 { "Content-Encoding:", 17, server_content_encoding },
1134 #endif /* def FEATURE_ZLIB */
1138 if (strncmpic(csp->http->cmd, "HEAD", 4))
1140 const struct parsers *v;
1141 struct list_entry *p;
1143 for (v = server_patterns_light; (err == JB_ERR_OK) && (v->str != NULL); v++)
1145 for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
1147 /* Header crunch()ed in previous run? -> ignore */
1148 if (p->str == NULL) continue;
1150 /* Does the current parser handle this header? */
1151 if (strncmpic(p->str, v->str, v->len) == 0)
1153 err = v->parser(csp, (char **)&(p->str));
1159 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1160 if ((JB_ERR_OK == err)
1161 && (csp->flags & CSP_FLAG_MODIFIED)
1162 && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
1163 && !(csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET))
1167 create_content_length_header(csp->content_length, header, sizeof(header));
1168 err = enlist(csp->headers, header);
1169 if (JB_ERR_OK == err)
1171 log_error(LOG_LEVEL_HEADER,
1172 "Content modified with no Content-Length header set. "
1173 "Created: %s.", header);
1176 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1182 /*********************************************************************
1184 * Function : header_tagger
1186 * Description : Executes all text substitutions from applying
1187 * tag actions and saves the result as tag.
1189 * XXX: Shares enough code with filter_header() and
1190 * pcrs_filter_response() to warrant some helper functions.
1193 * 1 : csp = Current client state (buffers, headers, etc...)
1194 * 2 : header = Header that is used as tagger input
1196 * Returns : JB_ERR_OK on success and always succeeds
1198 *********************************************************************/
1199 static jb_err header_tagger(struct client_state *csp, char *header)
1201 int wanted_filter_type;
1202 int multi_action_index;
1206 struct file_list *fl;
1207 struct re_filterfile_spec *b;
1208 struct list_entry *tag_name;
1210 int found_filters = 0;
1211 const size_t header_length = strlen(header);
1213 if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1215 wanted_filter_type = FT_SERVER_HEADER_TAGGER;
1216 multi_action_index = ACTION_MULTI_SERVER_HEADER_TAGGER;
1220 wanted_filter_type = FT_CLIENT_HEADER_TAGGER;
1221 multi_action_index = ACTION_MULTI_CLIENT_HEADER_TAGGER;
1224 /* Check if there are any filters */
1225 for (i = 0; i < MAX_AF_FILES; i++)
1238 if (0 == found_filters)
1240 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1241 "tagging enabled, but no taggers available.");
1245 for (i = 0; i < MAX_AF_FILES; i++)
1248 if ((NULL == fl) || (NULL == fl->f))
1251 * Either there are no filter files
1252 * left, or this filter file just
1253 * contains no valid filters.
1255 * Continue to be sure we don't miss
1256 * valid filter files that are chained
1257 * after empty or invalid ones.
1262 /* For all filters, */
1263 for (b = fl->f; b; b = b->next)
1265 if (b->type != wanted_filter_type)
1267 /* skip the ones we don't care about, */
1270 /* leaving only taggers that could apply, of which we use the ones, */
1271 for (tag_name = csp->action->multi[multi_action_index]->first;
1272 NULL != tag_name; tag_name = tag_name->next)
1274 /* that do apply, and */
1275 if (strcmp(b->name, tag_name->str) == 0)
1277 char *modified_tag = NULL;
1279 size_t size = header_length;
1280 pcrs_job *joblist = b->joblist;
1282 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1284 if (NULL == joblist)
1286 log_error(LOG_LEVEL_RE_FILTER,
1287 "Tagger %s has empty joblist. Nothing to do.", b->name);
1291 /* execute their pcrs_joblist on the header. */
1292 for (job = joblist; NULL != job; job = job->next)
1294 const int hits = pcrs_execute(job, tag, size, &modified_tag, &size);
1298 /* Success, continue with the modified version. */
1307 /* Tagger doesn't match */
1310 /* Regex failure, log it but continue anyway. */
1311 assert(NULL != header);
1312 log_error(LOG_LEVEL_ERROR,
1313 "Problems with tagger \'%s\' and header \'%s\': %s",
1314 b->name, *header, pcrs_strerror(hits));
1316 freez(modified_tag);
1320 if (b->dynamic) pcrs_free_joblist(joblist);
1322 /* If this tagger matched */
1328 * There is to technical limitation which makes
1329 * it impossible to use empty tags, but I assume
1330 * no one would do it intentionally.
1333 log_error(LOG_LEVEL_INFO,
1334 "Tagger \'%s\' created an empty tag. Ignored.",
1339 if (!list_contains_item(csp->tags, tag))
1341 if (JB_ERR_OK != enlist(csp->tags, tag))
1343 log_error(LOG_LEVEL_ERROR,
1344 "Insufficient memory to add tag \'%s\', "
1345 "based on tagger \'%s\' and header \'%s\'",
1346 tag, b->name, *header);
1350 char *action_message;
1352 * update the action bits right away, to make
1353 * tagging based on tags set by earlier taggers
1354 * of the same kind possible.
1356 if (update_action_bits_for_tag(csp, tag))
1358 action_message = "Action bits updated accordingly.";
1362 action_message = "No action bits update necessary.";
1365 log_error(LOG_LEVEL_HEADER,
1366 "Tagger \'%s\' added tag \'%s\'. %s",
1367 b->name, tag, action_message);
1372 /* XXX: Is this log-worthy? */
1373 log_error(LOG_LEVEL_HEADER,
1374 "Tagger \'%s\' didn't add tag \'%s\'. "
1375 "Tag already present", b->name, tag);
1378 } /* if the tagger matched */
1379 } /* if the tagger applies */
1380 } /* for every tagger that could apply */
1381 } /* for all filters */
1382 } /* for all filter files */
1387 /* here begins the family of parser functions that reformat header lines */
1389 /*********************************************************************
1391 * Function : filter_header
1393 * Description : Executes all text substitutions from all applying
1394 * +(server|client)-header-filter actions on the header.
1395 * Most of the code was copied from pcrs_filter_response,
1396 * including the rather short variable names
1399 * 1 : csp = Current client state (buffers, headers, etc...)
1400 * 2 : header = On input, pointer to header to modify.
1401 * On output, pointer to the modified header, or NULL
1402 * to remove the header. This function frees the
1403 * original string if necessary.
1405 * Returns : JB_ERR_OK on success and always succeeds
1407 *********************************************************************/
1408 static jb_err filter_header(struct client_state *csp, char **header)
1412 size_t size = strlen(*header);
1414 char *newheader = NULL;
1417 struct file_list *fl;
1418 struct re_filterfile_spec *b;
1419 struct list_entry *filtername;
1421 int i, found_filters = 0;
1422 int wanted_filter_type;
1423 int multi_action_index;
1425 if (csp->flags & CSP_FLAG_NO_FILTERING)
1430 if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1432 wanted_filter_type = FT_SERVER_HEADER_FILTER;
1433 multi_action_index = ACTION_MULTI_SERVER_HEADER_FILTER;
1437 wanted_filter_type = FT_CLIENT_HEADER_FILTER;
1438 multi_action_index = ACTION_MULTI_CLIENT_HEADER_FILTER;
1442 * Need to check the set of re_filterfiles...
1444 for (i = 0; i < MAX_AF_FILES; i++)
1457 if (0 == found_filters)
1459 log_error(LOG_LEVEL_ERROR, "Inconsistent configuration: "
1460 "header filtering enabled, but no matching filters available.");
1464 for (i = 0; i < MAX_AF_FILES; i++)
1467 if ((NULL == fl) || (NULL == fl->f))
1470 * Either there are no filter files
1471 * left, or this filter file just
1472 * contains no valid filters.
1474 * Continue to be sure we don't miss
1475 * valid filter files that are chained
1476 * after empty or invalid ones.
1481 * For all applying +filter actions, look if a filter by that
1482 * name exists and if yes, execute its pcrs_joblist on the
1485 for (b = fl->f; b; b = b->next)
1487 if (b->type != wanted_filter_type)
1489 /* Skip other filter types */
1493 for (filtername = csp->action->multi[multi_action_index]->first;
1494 filtername ; filtername = filtername->next)
1496 if (strcmp(b->name, filtername->str) == 0)
1498 int current_hits = 0;
1499 pcrs_job *joblist = b->joblist;
1501 if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1503 if (NULL == joblist)
1505 log_error(LOG_LEVEL_RE_FILTER, "Filter %s has empty joblist. Nothing to do.", b->name);
1509 log_error(LOG_LEVEL_RE_FILTER, "filtering \'%s\' (size %d) with \'%s\' ...",
1510 *header, size, b->name);
1512 /* Apply all jobs from the joblist */
1513 for (job = joblist; NULL != job; job = job->next)
1515 matches = pcrs_execute(job, *header, size, &newheader, &size);
1518 current_hits += matches;
1519 log_error(LOG_LEVEL_HEADER, "Transforming \"%s\" to \"%s\"", *header, newheader);
1521 *header = newheader;
1523 else if ( 0 == matches )
1525 /* Filter doesn't change header */
1531 log_error(LOG_LEVEL_ERROR, "Filtering \'%s\' with \'%s\' didn't work out: %s",
1532 *header, b->name, pcrs_strerror(matches));
1533 if (newheader != NULL)
1535 log_error(LOG_LEVEL_ERROR, "Freeing what's left: %s", newheader);
1541 if (b->dynamic) pcrs_free_joblist(joblist);
1543 log_error(LOG_LEVEL_RE_FILTER, "... produced %d hits (new size %d).", current_hits, size);
1544 hits += current_hits;
1551 * Additionally checking for hits is important because if
1552 * the continue hack is triggered, server headers can
1553 * arrive empty to separate multiple heads from each other.
1555 if ((0 == size) && hits)
1557 log_error(LOG_LEVEL_HEADER, "Removing empty header %s", *header);
1565 /*********************************************************************
1567 * Function : server_connection
1569 * Description : Makes sure a proper "Connection:" header is
1570 * set and signals connection_header_adder to
1574 * 1 : csp = Current client state (buffers, headers, etc...)
1575 * 2 : header = On input, pointer to header to modify.
1576 * On output, pointer to the modified header, or NULL
1577 * to remove the header. This function frees the
1578 * original string if necessary.
1580 * Returns : JB_ERR_OK on success, or
1581 * JB_ERR_MEMORY on out-of-memory error.
1583 *********************************************************************/
1584 static jb_err server_connection(struct client_state *csp, char **header)
1586 if (!strcmpic(*header, "Connection: keep-alive")
1587 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1588 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
1592 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1593 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1595 csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
1598 if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE))
1600 log_error(LOG_LEVEL_HEADER,
1601 "Keeping the server header '%s' around.", *header);
1604 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1606 char *old_header = *header;
1608 *header = strdup("Connection: close");
1611 return JB_ERR_MEMORY;
1613 log_error(LOG_LEVEL_HEADER, "Replaced: \'%s\' with \'%s\'", old_header, *header);
1618 /* Signal server_connection_adder() to return early. */
1619 csp->flags |= CSP_FLAG_SERVER_CONNECTION_HEADER_SET;
1625 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1626 /*********************************************************************
1628 * Function : server_keep_alive
1630 * Description : Stores the server's keep alive timeout.
1633 * 1 : csp = Current client state (buffers, headers, etc...)
1634 * 2 : header = On input, pointer to header to modify.
1635 * On output, pointer to the modified header, or NULL
1636 * to remove the header. This function frees the
1637 * original string if necessary.
1639 * Returns : JB_ERR_OK.
1641 *********************************************************************/
1642 static jb_err server_keep_alive(struct client_state *csp, char **header)
1644 unsigned int keep_alive_timeout;
1645 const char *timeout_position = strstr(*header, "timeout=");
1647 if ((NULL == timeout_position)
1648 || (1 != sscanf(timeout_position, "timeout=%u", &keep_alive_timeout)))
1650 log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header);
1654 if (keep_alive_timeout < csp->server_connection.keep_alive_timeout)
1656 log_error(LOG_LEVEL_HEADER,
1657 "Reducing keep-alive timeout from %u to %u.",
1658 csp->server_connection.keep_alive_timeout, keep_alive_timeout);
1659 csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1663 /* XXX: Is this log worthy? */
1664 log_error(LOG_LEVEL_HEADER,
1665 "Server keep-alive timeout is %u. Sticking with %u.",
1666 keep_alive_timeout, csp->server_connection.keep_alive_timeout);
1668 csp->flags |= CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET;
1675 /*********************************************************************
1677 * Function : server_proxy_connection
1679 * Description : Figures out whether or not we should add a
1680 * Proxy-Connection header.
1683 * 1 : csp = Current client state (buffers, headers, etc...)
1684 * 2 : header = On input, pointer to header to modify.
1685 * On output, pointer to the modified header, or NULL
1686 * to remove the header. This function frees the
1687 * original string if necessary.
1689 * Returns : JB_ERR_OK.
1691 *********************************************************************/
1692 static jb_err server_proxy_connection(struct client_state *csp, char **header)
1694 csp->flags |= CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET;
1699 /*********************************************************************
1701 * Function : client_keep_alive
1703 * Description : Stores the client's keep alive timeout.
1706 * 1 : csp = Current client state (buffers, headers, etc...)
1707 * 2 : header = On input, pointer to header to modify.
1708 * On output, pointer to the modified header, or NULL
1709 * to remove the header. This function frees the
1710 * original string if necessary.
1712 * Returns : JB_ERR_OK.
1714 *********************************************************************/
1715 static jb_err client_keep_alive(struct client_state *csp, char **header)
1717 unsigned int keep_alive_timeout;
1718 const char *timeout_position = strstr(*header, ": ");
1720 if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1722 log_error(LOG_LEVEL_HEADER,
1723 "keep-alive support is disabled. Crunching: %s.", *header);
1728 if ((NULL == timeout_position)
1729 || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout)))
1731 log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header);
1735 if (keep_alive_timeout < csp->config->keep_alive_timeout)
1737 log_error(LOG_LEVEL_HEADER,
1738 "Reducing keep-alive timeout from %u to %u.",
1739 csp->config->keep_alive_timeout, keep_alive_timeout);
1740 csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1744 /* XXX: Is this log worthy? */
1745 log_error(LOG_LEVEL_HEADER,
1746 "Client keep-alive timeout is %u. Sticking with %u.",
1747 keep_alive_timeout, csp->config->keep_alive_timeout);
1753 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1757 /*********************************************************************
1759 * Function : client_connection
1761 * Description : Makes sure a proper "Connection:" header is
1762 * set and signals connection_header_adder
1766 * 1 : csp = Current client state (buffers, headers, etc...)
1767 * 2 : header = On input, pointer to header to modify.
1768 * On output, pointer to the modified header, or NULL
1769 * to remove the header. This function frees the
1770 * original string if necessary.
1772 * Returns : JB_ERR_OK on success, or
1773 * JB_ERR_MEMORY on out-of-memory error.
1775 *********************************************************************/
1776 static jb_err client_connection(struct client_state *csp, char **header)
1778 static const char connection_close[] = "Connection: close";
1780 if (!strcmpic(*header, connection_close))
1782 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1783 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING))
1785 if (!strcmpic(csp->http->ver, "HTTP/1.1"))
1787 log_error(LOG_LEVEL_HEADER,
1788 "Removing \'%s\' to imply keep-alive.", *header);
1793 char *old_header = *header;
1795 *header = strdup("Connection: keep-alive");
1798 return JB_ERR_MEMORY;
1800 log_error(LOG_LEVEL_HEADER,
1801 "Replaced: \'%s\' with \'%s\'", old_header, *header);
1807 log_error(LOG_LEVEL_HEADER,
1808 "Keeping the client header '%s' around. "
1809 "The connection will not be kept alive.",
1811 csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1814 else if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1816 log_error(LOG_LEVEL_HEADER,
1817 "Keeping the client header '%s' around. "
1818 "The server connection will be kept alive if possible.",
1820 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1821 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1825 char *old_header = *header;
1827 *header = strdup(connection_close);
1830 return JB_ERR_MEMORY;
1832 log_error(LOG_LEVEL_HEADER,
1833 "Replaced: \'%s\' with \'%s\'", old_header, *header);
1837 /* Signal client_connection_adder() to return early. */
1838 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET;
1844 /*********************************************************************
1846 * Function : crumble
1848 * Description : This is called if a header matches a pattern to "crunch"
1851 * 1 : csp = Current client state (buffers, headers, etc...)
1852 * 2 : header = On input, pointer to header to modify.
1853 * On output, pointer to the modified header, or NULL
1854 * to remove the header. This function frees the
1855 * original string if necessary.
1857 * Returns : JB_ERR_OK on success, or
1858 * JB_ERR_MEMORY on out-of-memory error.
1860 *********************************************************************/
1861 static jb_err crumble(struct client_state *csp, char **header)
1864 log_error(LOG_LEVEL_HEADER, "crumble crunched: %s!", *header);
1870 /*********************************************************************
1872 * Function : crunch_server_header
1874 * Description : Crunch server header if it matches a string supplied by the
1875 * user. Called from `sed'.
1878 * 1 : csp = Current client state (buffers, headers, etc...)
1879 * 2 : header = On input, pointer to header to modify.
1880 * On output, pointer to the modified header, or NULL
1881 * to remove the header. This function frees the
1882 * original string if necessary.
1884 * Returns : JB_ERR_OK on success and always succeeds
1886 *********************************************************************/
1887 static jb_err crunch_server_header(struct client_state *csp, char **header)
1889 const char *crunch_pattern;
1891 /* Do we feel like crunching? */
1892 if ((csp->action->flags & ACTION_CRUNCH_SERVER_HEADER))
1894 crunch_pattern = csp->action->string[ACTION_STRING_SERVER_HEADER];
1896 /* Is the current header the lucky one? */
1897 if (strstr(*header, crunch_pattern))
1899 log_error(LOG_LEVEL_HEADER, "Crunching server header: %s (contains: %s)", *header, crunch_pattern);
1908 /*********************************************************************
1910 * Function : server_content_type
1912 * Description : Set the content-type for filterable types (text/.*,
1913 * .*xml.*, javascript and image/gif) unless filtering has been
1914 * forbidden (CT_TABOO) while parsing earlier headers.
1915 * NOTE: Since text/plain is commonly used by web servers
1916 * for files whose correct type is unknown, we don't
1917 * set CT_TEXT for it.
1920 * 1 : csp = Current client state (buffers, headers, etc...)
1921 * 2 : header = On input, pointer to header to modify.
1922 * On output, pointer to the modified header, or NULL
1923 * to remove the header. This function frees the
1924 * original string if necessary.
1926 * Returns : JB_ERR_OK on success, or
1927 * JB_ERR_MEMORY on out-of-memory error.
1929 *********************************************************************/
1930 static jb_err server_content_type(struct client_state *csp, char **header)
1932 /* Remove header if it isn't the first Content-Type header */
1933 if ((csp->content_type & CT_DECLARED))
1936 * Another, slightly slower, way to see if
1937 * we already parsed another Content-Type header.
1939 assert(NULL != get_header_value(csp->headers, "Content-Type:"));
1941 log_error(LOG_LEVEL_ERROR,
1942 "Multiple Content-Type headers. Removing and ignoring: \'%s\'",
1950 * Signal that the Content-Type has been set.
1952 csp->content_type |= CT_DECLARED;
1954 if (!(csp->content_type & CT_TABOO))
1957 * XXX: The assumption that text/plain is a sign of
1958 * binary data seems to be somewhat unreasonable nowadays
1959 * and should be dropped after 3.0.8 is out.
1961 if ((strstr(*header, "text/") && !strstr(*header, "plain"))
1962 || strstr(*header, "xml")
1963 || strstr(*header, "application/x-javascript"))
1965 csp->content_type |= CT_TEXT;
1967 else if (strstr(*header, "image/gif"))
1969 csp->content_type |= CT_GIF;
1974 * Are we messing with the content type?
1976 if (csp->action->flags & ACTION_CONTENT_TYPE_OVERWRITE)
1979 * Make sure the user doesn't accidently
1980 * change the content type of binary documents.
1982 if ((csp->content_type & CT_TEXT) || (csp->action->flags & ACTION_FORCE_TEXT_MODE))
1985 *header = strdup("Content-Type: ");
1986 string_append(header, csp->action->string[ACTION_STRING_CONTENT_TYPE]);
1990 log_error(LOG_LEVEL_HEADER, "Insufficient memory to replace Content-Type!");
1991 return JB_ERR_MEMORY;
1993 log_error(LOG_LEVEL_HEADER, "Modified: %s!", *header);
1997 log_error(LOG_LEVEL_HEADER, "%s not replaced. "
1998 "It doesn't look like a content type that should be filtered. "
1999 "Enable force-text-mode if you know what you're doing.", *header);
2007 /*********************************************************************
2009 * Function : server_transfer_coding
2011 * Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses
2012 * - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked"
2013 * - Remove header if body was chunked but has been
2014 * de-chunked for filtering.
2017 * 1 : csp = Current client state (buffers, headers, etc...)
2018 * 2 : header = On input, pointer to header to modify.
2019 * On output, pointer to the modified header, or NULL
2020 * to remove the header. This function frees the
2021 * original string if necessary.
2023 * Returns : JB_ERR_OK on success, or
2024 * JB_ERR_MEMORY on out-of-memory error.
2026 *********************************************************************/
2027 static jb_err server_transfer_coding(struct client_state *csp, char **header)
2030 * Turn off pcrs and gif filtering if body compressed
2032 if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
2036 * XXX: Added to test if we could use CT_GZIP and CT_DEFLATE here.
2038 log_error(LOG_LEVEL_INFO, "Marking content type for %s as CT_TABOO because of %s.",
2039 csp->http->cmd, *header);
2040 #endif /* def FEATURE_ZLIB */
2041 csp->content_type = CT_TABOO;
2045 * Raise flag if body chunked
2047 if (strstr(*header, "chunked"))
2049 csp->flags |= CSP_FLAG_CHUNKED;
2052 * If the body was modified, it has been de-chunked first
2053 * and the header must be removed.
2055 * FIXME: If there is more than one transfer encoding,
2056 * only the "chunked" part should be removed here.
2058 if (csp->flags & CSP_FLAG_MODIFIED)
2060 log_error(LOG_LEVEL_HEADER, "Removing: %s", *header);
2069 /*********************************************************************
2071 * Function : server_content_encoding
2073 * Description : This function is run twice for each request,
2074 * unless FEATURE_ZLIB and filtering are disabled.
2076 * The first run is used to check if the content
2077 * is compressed, if FEATURE_ZLIB is disabled
2078 * filtering is then disabled as well, if FEATURE_ZLIB
2079 * is enabled the content is marked for decompression.
2081 * The second run is used to remove the Content-Encoding
2082 * header if the decompression was successful.
2085 * 1 : csp = Current client state (buffers, headers, etc...)
2086 * 2 : header = On input, pointer to header to modify.
2087 * On output, pointer to the modified header, or NULL
2088 * to remove the header. This function frees the
2089 * original string if necessary.
2091 * Returns : JB_ERR_OK on success, or
2092 * JB_ERR_MEMORY on out-of-memory error.
2094 *********************************************************************/
2095 static jb_err server_content_encoding(struct client_state *csp, char **header)
2098 if ((csp->flags & CSP_FLAG_MODIFIED)
2099 && (csp->content_type & (CT_GZIP | CT_DEFLATE)))
2102 * We successfully decompressed the content,
2103 * and have to clean the header now, so the
2104 * client no longer expects compressed data..
2106 * XXX: There is a difference between cleaning
2107 * and removing it completely.
2109 log_error(LOG_LEVEL_HEADER, "Crunching: %s", *header);
2112 else if (strstr(*header, "gzip"))
2114 /* Mark for gzip decompression */
2115 csp->content_type |= CT_GZIP;
2117 else if (strstr(*header, "deflate"))
2119 /* Mark for zlib decompression */
2120 csp->content_type |= CT_DEFLATE;
2122 else if (strstr(*header, "compress"))
2125 * We can't decompress this; therefore we can't filter
2128 csp->content_type |= CT_TABOO;
2130 #else /* !defined(FEATURE_ZLIB) */
2131 if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
2134 * Body is compressed, turn off pcrs and gif filtering.
2136 csp->content_type |= CT_TABOO;
2139 * Log a warning if the user expects the content to be filtered.
2141 if ((csp->rlist != NULL) &&
2142 (!list_is_empty(csp->action->multi[ACTION_MULTI_FILTER])))
2144 log_error(LOG_LEVEL_INFO,
2145 "Compressed content detected, content filtering disabled. "
2146 "Consider recompiling Privoxy with zlib support or "
2147 "enable the prevent-compression action.");
2150 #endif /* defined(FEATURE_ZLIB) */
2157 /*********************************************************************
2159 * Function : server_adjust_content_length
2161 * Description : Adjust Content-Length header if we modified
2165 * 1 : csp = Current client state (buffers, headers, etc...)
2166 * 2 : header = On input, pointer to header to modify.
2167 * On output, pointer to the modified header, or NULL
2168 * to remove the header. This function frees the
2169 * original string if necessary.
2171 * Returns : JB_ERR_OK on success, or
2172 * JB_ERR_MEMORY on out-of-memory error.
2174 *********************************************************************/
2175 static jb_err server_adjust_content_length(struct client_state *csp, char **header)
2177 /* Regenerate header if the content was modified. */
2178 if (csp->flags & CSP_FLAG_MODIFIED)
2180 const size_t header_length = 50;
2182 *header = malloc(header_length);
2183 if (*header == NULL)
2185 return JB_ERR_MEMORY;
2187 create_content_length_header(csp->content_length, *header, header_length);
2188 log_error(LOG_LEVEL_HEADER,
2189 "Adjusted Content-Length to %llu", csp->content_length);
2196 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2197 /*********************************************************************
2199 * Function : server_save_content_length
2201 * Description : Save the Content-Length sent by the server.
2204 * 1 : csp = Current client state (buffers, headers, etc...)
2205 * 2 : header = On input, pointer to header to modify.
2206 * On output, pointer to the modified header, or NULL
2207 * to remove the header. This function frees the
2208 * original string if necessary.
2210 * Returns : JB_ERR_OK on success, or
2211 * JB_ERR_MEMORY on out-of-memory error.
2213 *********************************************************************/
2214 static jb_err server_save_content_length(struct client_state *csp, char **header)
2216 unsigned long long content_length = 0;
2218 assert(*(*header+14) == ':');
2221 if (1 != sscanf(*header+14, ": %I64u", &content_length))
2223 if (1 != sscanf(*header+14, ": %llu", &content_length))
2226 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2231 csp->expected_content_length = content_length;
2232 csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
2233 csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2238 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2241 /*********************************************************************
2243 * Function : server_content_md5
2245 * Description : Crumble any Content-MD5 headers if the document was
2246 * modified. FIXME: Should we re-compute instead?
2249 * 1 : csp = Current client state (buffers, headers, etc...)
2250 * 2 : header = On input, pointer to header to modify.
2251 * On output, pointer to the modified header, or NULL
2252 * to remove the header. This function frees the
2253 * original string if necessary.
2255 * Returns : JB_ERR_OK on success, or
2256 * JB_ERR_MEMORY on out-of-memory error.
2258 *********************************************************************/
2259 static jb_err server_content_md5(struct client_state *csp, char **header)
2261 if (csp->flags & CSP_FLAG_MODIFIED)
2263 log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5");
2271 /*********************************************************************
2273 * Function : server_content_disposition
2275 * Description : If enabled, blocks or modifies the "Content-Disposition" header.
2276 * Called from `sed'.
2279 * 1 : csp = Current client state (buffers, headers, etc...)
2280 * 2 : header = On input, pointer to header to modify.
2281 * On output, pointer to the modified header, or NULL
2282 * to remove the header. This function frees the
2283 * original string if necessary.
2285 * Returns : JB_ERR_OK on success, or
2286 * JB_ERR_MEMORY on out-of-memory error.
2288 *********************************************************************/
2289 static jb_err server_content_disposition(struct client_state *csp, char **header)
2294 * Are we messing with the Content-Disposition header?
2296 if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0)
2302 newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION];
2304 if ((newval == NULL) || (0 == strcmpic(newval, "block")))
2307 * Blocking content-disposition header
2309 log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2316 * Replacing Content-Disposition header
2319 *header = strdup("Content-Disposition: ");
2320 string_append(header, newval);
2322 if (*header != NULL)
2324 log_error(LOG_LEVEL_HEADER,
2325 "Content-Disposition header crunched and replaced with: %s", *header);
2328 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2332 /*********************************************************************
2334 * Function : server_last_modified
2336 * Description : Changes Last-Modified header to the actual date
2337 * to help hide-if-modified-since.
2338 * Called from `sed'.
2341 * 1 : csp = Current client state (buffers, headers, etc...)
2342 * 2 : header = On input, pointer to header to modify.
2343 * On output, pointer to the modified header, or NULL
2344 * to remove the header. This function frees the
2345 * original string if necessary.
2347 * Returns : JB_ERR_OK on success, or
2348 * JB_ERR_MEMORY on out-of-memory error.
2350 *********************************************************************/
2351 static jb_err server_last_modified(struct client_state *csp, char **header)
2354 char buf[BUFFER_SIZE];
2357 #ifdef HAVE_GMTIME_R
2360 struct tm *timeptr = NULL;
2361 time_t now, last_modified;
2362 long int days, hours, minutes, seconds;
2365 * Are we messing with the Last-Modified header?
2367 if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0)
2373 newval = csp->action->string[ACTION_STRING_LAST_MODIFIED];
2375 if (0 == strcmpic(newval, "block") )
2378 * Blocking Last-Modified header. Useless but why not.
2380 log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2384 else if (0 == strcmpic(newval, "reset-to-request-time"))
2387 * Setting Last-Modified Header to now.
2389 get_http_time(0, buf, sizeof(buf));
2391 *header = strdup("Last-Modified: ");
2392 string_append(header, buf);
2394 if (*header == NULL)
2396 log_error(LOG_LEVEL_HEADER, "Insufficient memory. Last-Modified header got lost, boohoo.");
2400 log_error(LOG_LEVEL_HEADER, "Reset to present time: %s", *header);
2403 else if (0 == strcmpic(newval, "randomize"))
2405 const char *header_time = *header + sizeof("Last-Modified:");
2407 log_error(LOG_LEVEL_HEADER, "Randomizing: %s", *header);
2409 #ifdef HAVE_GMTIME_R
2410 gmtime_r(&now, &gmt);
2411 #elif defined(MUTEX_LOCKS_AVAILABLE)
2412 privoxy_mutex_lock(&gmtime_mutex);
2414 privoxy_mutex_unlock(&gmtime_mutex);
2418 if (JB_ERR_OK != parse_header_time(header_time, &last_modified))
2420 log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
2425 long int rtime = (long int)difftime(now, last_modified);
2428 const int negative_delta = (rtime < 0);
2433 log_error(LOG_LEVEL_HEADER, "Server time in the future.");
2435 rtime = pick_from_range(rtime);
2440 last_modified += rtime;
2441 #ifdef HAVE_GMTIME_R
2442 timeptr = gmtime_r(&last_modified, &gmt);
2443 #elif defined(MUTEX_LOCKS_AVAILABLE)
2444 privoxy_mutex_lock(&gmtime_mutex);
2445 timeptr = gmtime(&last_modified);
2446 privoxy_mutex_unlock(&gmtime_mutex);
2448 timeptr = gmtime(&last_modified);
2450 if ((NULL == timeptr) || !strftime(newheader,
2451 sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
2453 log_error(LOG_LEVEL_ERROR,
2454 "Randomizing '%s' failed. Crunching the header without replacement.",
2461 *header = strdup("Last-Modified: ");
2462 string_append(header, newheader);
2464 if (*header == NULL)
2466 log_error(LOG_LEVEL_ERROR, "Insufficient memory, header crunched without replacement.");
2467 return JB_ERR_MEMORY;
2470 days = rtime / (3600 * 24);
2471 hours = rtime / 3600 % 24;
2472 minutes = rtime / 60 % 60;
2473 seconds = rtime % 60;
2475 log_error(LOG_LEVEL_HEADER,
2476 "Randomized: %s (added %d da%s %d hou%s %d minut%s %d second%s",
2477 *header, days, (days == 1) ? "y" : "ys", hours, (hours == 1) ? "r" : "rs",
2478 minutes, (minutes == 1) ? "e" : "es", seconds, (seconds == 1) ? ")" : "s)");
2482 log_error(LOG_LEVEL_HEADER, "Randomized ... or not. No time difference to work with.");
2491 /*********************************************************************
2493 * Function : client_accept_encoding
2495 * Description : Rewrite the client's Accept-Encoding header so that
2496 * if doesn't allow compression, if the action applies.
2497 * Note: For HTTP/1.0 the absence of the header is enough.
2500 * 1 : csp = Current client state (buffers, headers, etc...)
2501 * 2 : header = On input, pointer to header to modify.
2502 * On output, pointer to the modified header, or NULL
2503 * to remove the header. This function frees the
2504 * original string if necessary.
2506 * Returns : JB_ERR_OK on success, or
2507 * JB_ERR_MEMORY on out-of-memory error.
2509 *********************************************************************/
2510 static jb_err client_accept_encoding(struct client_state *csp, char **header)
2512 if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
2514 log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content");
2518 /* Temporarily disable the correct behaviour to
2519 * work around a PHP bug.
2521 * if (!strcmpic(csp->http->ver, "HTTP/1.1"))
2523 * *header = strdup("Accept-Encoding: identity;q=1.0, *;q=0");
2524 * if (*header == NULL)
2526 * return JB_ERR_MEMORY;
2537 /*********************************************************************
2539 * Function : client_te
2541 * Description : Rewrite the client's TE header so that
2542 * if doesn't allow compression, if the action applies.
2545 * 1 : csp = Current client state (buffers, headers, etc...)
2546 * 2 : header = On input, pointer to header to modify.
2547 * On output, pointer to the modified header, or NULL
2548 * to remove the header. This function frees the
2549 * original string if necessary.
2551 * Returns : JB_ERR_OK on success, or
2552 * JB_ERR_MEMORY on out-of-memory error.
2554 *********************************************************************/
2555 static jb_err client_te(struct client_state *csp, char **header)
2557 if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
2560 log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress transfer");
2567 /*********************************************************************
2569 * Function : client_referrer
2571 * Description : Handle the "referer" config setting properly.
2572 * Called from `sed'.
2575 * 1 : csp = Current client state (buffers, headers, etc...)
2576 * 2 : header = On input, pointer to header to modify.
2577 * On output, pointer to the modified header, or NULL
2578 * to remove the header. This function frees the
2579 * original string if necessary.
2581 * Returns : JB_ERR_OK on success, or
2582 * JB_ERR_MEMORY on out-of-memory error.
2584 *********************************************************************/
2585 static jb_err client_referrer(struct client_state *csp, char **header)
2587 const char *parameter;
2588 /* booleans for parameters we have to check multiple times */
2589 int parameter_conditional_block;
2590 int parameter_conditional_forge;
2592 #ifdef FEATURE_FORCE_LOAD
2594 * Since the referrer can include the prefix even
2595 * if the request itself is non-forced, we must
2596 * clean it unconditionally.
2598 * XXX: strclean is too broad
2600 strclean(*header, FORCE_PREFIX);
2601 #endif /* def FEATURE_FORCE_LOAD */
2603 if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
2605 /* Nothing left to do */
2609 parameter = csp->action->string[ACTION_STRING_REFERER];
2610 assert(parameter != NULL);
2611 parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
2612 parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
2614 if (!parameter_conditional_block && !parameter_conditional_forge)
2617 * As conditional-block and conditional-forge are the only
2618 * parameters that rely on the original referrer, we can
2619 * remove it now for all the others.
2624 if (0 == strcmpic(parameter, "block"))
2626 log_error(LOG_LEVEL_HEADER, "Referer crunched!");
2629 else if (parameter_conditional_block || parameter_conditional_forge)
2631 return handle_conditional_hide_referrer_parameter(header,
2632 csp->http->hostport, parameter_conditional_block);
2634 else if (0 == strcmpic(parameter, "forge"))
2636 return create_forged_referrer(header, csp->http->hostport);
2640 /* interpret parameter as user-supplied referer to fake */
2641 return create_fake_referrer(header, parameter);
2646 /*********************************************************************
2648 * Function : client_accept_language
2650 * Description : Handle the "Accept-Language" config setting properly.
2651 * Called from `sed'.
2654 * 1 : csp = Current client state (buffers, headers, etc...)
2655 * 2 : header = On input, pointer to header to modify.
2656 * On output, pointer to the modified header, or NULL
2657 * to remove the header. This function frees the
2658 * original string if necessary.
2660 * Returns : JB_ERR_OK on success, or
2661 * JB_ERR_MEMORY on out-of-memory error.
2663 *********************************************************************/
2664 static jb_err client_accept_language(struct client_state *csp, char **header)
2669 * Are we messing with the Accept-Language?
2671 if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0)
2673 /*I don't think so*/
2677 newval = csp->action->string[ACTION_STRING_LANGUAGE];
2679 if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
2682 * Blocking Accept-Language header
2684 log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!");
2691 * Replacing Accept-Language header
2694 *header = strdup("Accept-Language: ");
2695 string_append(header, newval);
2697 if (*header == NULL)
2699 log_error(LOG_LEVEL_ERROR,
2700 "Insufficient memory. Accept-Language header crunched without replacement.");
2704 log_error(LOG_LEVEL_HEADER,
2705 "Accept-Language header crunched and replaced with: %s", *header);
2708 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2712 /*********************************************************************
2714 * Function : crunch_client_header
2716 * Description : Crunch client header if it matches a string supplied by the
2717 * user. Called from `sed'.
2720 * 1 : csp = Current client state (buffers, headers, etc...)
2721 * 2 : header = On input, pointer to header to modify.
2722 * On output, pointer to the modified header, or NULL
2723 * to remove the header. This function frees the
2724 * original string if necessary.
2726 * Returns : JB_ERR_OK on success and always succeeds
2728 *********************************************************************/
2729 static jb_err crunch_client_header(struct client_state *csp, char **header)
2731 const char *crunch_pattern;
2733 /* Do we feel like crunching? */
2734 if ((csp->action->flags & ACTION_CRUNCH_CLIENT_HEADER))
2736 crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER];
2738 /* Is the current header the lucky one? */
2739 if (strstr(*header, crunch_pattern))
2741 log_error(LOG_LEVEL_HEADER, "Crunching client header: %s (contains: %s)", *header, crunch_pattern);
2749 /*********************************************************************
2751 * Function : client_uagent
2753 * Description : Handle the "user-agent" config setting properly
2754 * and remember its original value to enable browser
2755 * bug workarounds. Called from `sed'.
2758 * 1 : csp = Current client state (buffers, headers, etc...)
2759 * 2 : header = On input, pointer to header to modify.
2760 * On output, pointer to the modified header, or NULL
2761 * to remove the header. This function frees the
2762 * original string if necessary.
2764 * Returns : JB_ERR_OK on success, or
2765 * JB_ERR_MEMORY on out-of-memory error.
2767 *********************************************************************/
2768 static jb_err client_uagent(struct client_state *csp, char **header)
2772 if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0)
2777 newval = csp->action->string[ACTION_STRING_USER_AGENT];
2784 *header = strdup("User-Agent: ");
2785 string_append(header, newval);
2787 log_error(LOG_LEVEL_HEADER, "Modified: %s", *header);
2789 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2793 /*********************************************************************
2795 * Function : client_ua
2797 * Description : Handle "ua-" headers properly. Called from `sed'.
2800 * 1 : csp = Current client state (buffers, headers, etc...)
2801 * 2 : header = On input, pointer to header to modify.
2802 * On output, pointer to the modified header, or NULL
2803 * to remove the header. This function frees the
2804 * original string if necessary.
2806 * Returns : JB_ERR_OK on success, or
2807 * JB_ERR_MEMORY on out-of-memory error.
2809 *********************************************************************/
2810 static jb_err client_ua(struct client_state *csp, char **header)
2812 if ((csp->action->flags & ACTION_HIDE_USER_AGENT) != 0)
2814 log_error(LOG_LEVEL_HEADER, "crunched User-Agent!");
2822 /*********************************************************************
2824 * Function : client_from
2826 * Description : Handle the "from" config setting properly.
2827 * Called from `sed'.
2830 * 1 : csp = Current client state (buffers, headers, etc...)
2831 * 2 : header = On input, pointer to header to modify.
2832 * On output, pointer to the modified header, or NULL
2833 * to remove the header. This function frees the
2834 * original string if necessary.
2836 * Returns : JB_ERR_OK on success, or
2837 * JB_ERR_MEMORY on out-of-memory error.
2839 *********************************************************************/
2840 static jb_err client_from(struct client_state *csp, char **header)
2844 if ((csp->action->flags & ACTION_HIDE_FROM) == 0)
2851 newval = csp->action->string[ACTION_STRING_FROM];
2854 * Are we blocking the e-mail address?
2856 if ((newval == NULL) || (0 == strcmpic(newval, "block")) )
2858 log_error(LOG_LEVEL_HEADER, "crunched From!");
2862 log_error(LOG_LEVEL_HEADER, " modified");
2864 *header = strdup("From: ");
2865 string_append(header, newval);
2867 return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2871 /*********************************************************************
2873 * Function : client_send_cookie
2875 * Description : Crunches the "cookie" header if necessary.
2876 * Called from `sed'.
2878 * XXX: Stupid name, doesn't send squat.
2881 * 1 : csp = Current client state (buffers, headers, etc...)
2882 * 2 : header = On input, pointer to header to modify.
2883 * On output, pointer to the modified header, or NULL
2884 * to remove the header. This function frees the
2885 * original string if necessary.
2887 * Returns : JB_ERR_OK on success, or
2888 * JB_ERR_MEMORY on out-of-memory error.
2890 *********************************************************************/
2891 static jb_err client_send_cookie(struct client_state *csp, char **header)
2893 if (csp->action->flags & ACTION_NO_COOKIE_READ)
2895 log_error(LOG_LEVEL_HEADER, "Crunched outgoing cookie: %s", *header);
2903 /*********************************************************************
2905 * Function : client_x_forwarded
2907 * Description : Handle the "x-forwarded-for" config setting properly,
2908 * also used in the add_client_headers list. Called from `sed'.
2911 * 1 : csp = Current client state (buffers, headers, etc...)
2912 * 2 : header = On input, pointer to header to modify.
2913 * On output, pointer to the modified header, or NULL
2914 * to remove the header. This function frees the
2915 * original string if necessary.
2917 * Returns : JB_ERR_OK on success, or
2918 * JB_ERR_MEMORY on out-of-memory error.
2920 *********************************************************************/
2921 jb_err client_x_forwarded(struct client_state *csp, char **header)
2923 if (0 != (csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR))
2925 const char *parameter = csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR];
2927 if (0 == strcmpic(parameter, "block"))
2930 log_error(LOG_LEVEL_HEADER, "crunched x-forwarded-for!");
2932 else if (0 == strcmpic(parameter, "add"))
2934 string_append(header, ", ");
2935 string_append(header, csp->ip_addr_str);
2937 if (*header == NULL)
2939 return JB_ERR_MEMORY;
2941 log_error(LOG_LEVEL_HEADER,
2942 "Appended client IP address to %s", *header);
2943 csp->flags |= CSP_FLAG_X_FORWARDED_FOR_APPENDED;
2947 log_error(LOG_LEVEL_FATAL,
2948 "Invalid change-x-forwarded-for parameter: '%s'", parameter);
2956 /*********************************************************************
2958 * Function : client_max_forwards
2960 * Description : If the HTTP method is OPTIONS or TRACE, subtract one
2961 * from the value of the Max-Forwards header field.
2964 * 1 : csp = Current client state (buffers, headers, etc...)
2965 * 2 : header = On input, pointer to header to modify.
2966 * On output, pointer to the modified header, or NULL
2967 * to remove the header. This function frees the
2968 * original string if necessary.
2970 * Returns : JB_ERR_OK on success, or
2971 * JB_ERR_MEMORY on out-of-memory error.
2973 *********************************************************************/
2974 static jb_err client_max_forwards(struct client_state *csp, char **header)
2978 if ((0 == strcmpic(csp->http->gpc, "trace")) ||
2979 (0 == strcmpic(csp->http->gpc, "options")))
2981 assert(*(*header+12) == ':');
2982 if (1 == sscanf(*header+12, ": %d", &max_forwards))
2984 if (max_forwards > 0)
2986 snprintf(*header, strlen(*header)+1, "Max-Forwards: %d", --max_forwards);
2987 log_error(LOG_LEVEL_HEADER,
2988 "Max-Forwards value for %s request reduced to %d.",
2989 csp->http->gpc, max_forwards);
2991 else if (max_forwards < 0)
2993 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2999 log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
3008 /*********************************************************************
3010 * Function : client_host
3012 * Description : If the request URI did not contain host and
3013 * port information, parse and evaluate the Host
3016 * Also, kill ill-formed HOST: headers as sent by
3017 * Apple's iTunes software when used with a proxy.
3020 * 1 : csp = Current client state (buffers, headers, etc...)
3021 * 2 : header = On input, pointer to header to modify.
3022 * On output, pointer to the modified header, or NULL
3023 * to remove the header. This function frees the
3024 * original string if necessary.
3026 * Returns : JB_ERR_OK on success, or
3027 * JB_ERR_MEMORY on out-of-memory error.
3029 *********************************************************************/
3030 static jb_err client_host(struct client_state *csp, char **header)
3035 * If the header field name is all upper-case, chances are that it's
3036 * an ill-formed one from iTunes. BTW, killing innocent headers here is
3037 * not a problem -- they are regenerated later.
3039 if ((*header)[1] == 'O')
3041 log_error(LOG_LEVEL_HEADER, "Killed all-caps Host header line: %s", *header);
3046 if (!csp->http->hostport || (*csp->http->hostport == '*') ||
3047 *csp->http->hostport == ' ' || *csp->http->hostport == '\0')
3050 if (NULL == (p = strdup((*header)+6)))
3052 return JB_ERR_MEMORY;
3055 if (NULL == (q = strdup(p)))
3058 return JB_ERR_MEMORY;
3061 freez(csp->http->hostport);
3062 csp->http->hostport = p;
3063 freez(csp->http->host);
3064 csp->http->host = q;
3065 q = strchr(csp->http->host, ':');
3068 /* Terminate hostname and evaluate port string */
3070 csp->http->port = atoi(q);
3074 csp->http->port = csp->http->ssl ? 443 : 80;
3077 log_error(LOG_LEVEL_HEADER, "New host and port from Host field: %s = %s:%d",
3078 csp->http->hostport, csp->http->host, csp->http->port);
3081 /* Signal client_host_adder() to return right away */
3082 csp->flags |= CSP_FLAG_HOST_HEADER_IS_SET;
3088 /*********************************************************************
3090 * Function : client_if_modified_since
3092 * Description : Remove or modify the If-Modified-Since header.
3095 * 1 : csp = Current client state (buffers, headers, etc...)
3096 * 2 : header = On input, pointer to header to modify.
3097 * On output, pointer to the modified header, or NULL
3098 * to remove the header. This function frees the
3099 * original string if necessary.
3101 * Returns : JB_ERR_OK on success, or
3102 * JB_ERR_MEMORY on out-of-memory error.
3104 *********************************************************************/
3105 static jb_err client_if_modified_since(struct client_state *csp, char **header)
3108 #ifdef HAVE_GMTIME_R
3111 struct tm *timeptr = NULL;
3114 long int hours, minutes, seconds;
3117 if ( 0 == strcmpic(*header, "If-Modified-Since: Wed, 08 Jun 1955 12:00:00 GMT"))
3120 * The client got an error message because of a temporary problem,
3121 * the problem is gone and the client now tries to revalidate our
3122 * error message on the real server. The revalidation would always
3123 * end with the transmission of the whole document and there is
3124 * no need to expose the bogus If-Modified-Since header.
3126 log_error(LOG_LEVEL_HEADER, "Crunching useless If-Modified-Since header.");
3129 else if (csp->action->flags & ACTION_HIDE_IF_MODIFIED_SINCE)
3131 newval = csp->action->string[ACTION_STRING_IF_MODIFIED_SINCE];
3133 if ((0 == strcmpic(newval, "block")))
3135 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3138 else /* add random value */
3140 const char *header_time = *header + sizeof("If-Modified-Since:");
3142 if (JB_ERR_OK != parse_header_time(header_time, &tm))
3144 log_error(LOG_LEVEL_HEADER, "Couldn't parse: %s in %s (crunching!)", header_time, *header);
3149 long int rtime = strtol(newval, &endptr, 0);
3150 const int negative_range = (rtime < 0);
3154 log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %d minut%s)",
3155 *header, rtime, (rtime == 1 || rtime == -1) ? "e": "es");
3161 rtime = pick_from_range(rtime);
3165 log_error(LOG_LEVEL_ERROR, "Random range is 0. Assuming time transformation test.",
3168 tm += rtime * (negative_range ? -1 : 1);
3169 #ifdef HAVE_GMTIME_R
3170 timeptr = gmtime_r(&tm, &gmt);
3171 #elif defined(MUTEX_LOCKS_AVAILABLE)
3172 privoxy_mutex_lock(&gmtime_mutex);
3173 timeptr = gmtime(&tm);
3174 privoxy_mutex_unlock(&gmtime_mutex);
3176 timeptr = gmtime(&tm);
3178 if ((NULL == timeptr) || !strftime(newheader,
3179 sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
3181 log_error(LOG_LEVEL_ERROR,
3182 "Randomizing '%s' failed. Crunching the header without replacement.",
3189 *header = strdup("If-Modified-Since: ");
3190 string_append(header, newheader);
3192 if (*header == NULL)
3194 log_error(LOG_LEVEL_HEADER, "Insufficient memory, header crunched without replacement.");
3195 return JB_ERR_MEMORY;
3198 hours = rtime / 3600;
3199 minutes = rtime / 60 % 60;
3200 seconds = rtime % 60;
3202 log_error(LOG_LEVEL_HEADER,
3203 "Randomized: %s (%s %d hou%s %d minut%s %d second%s",
3204 *header, (negative_range) ? "subtracted" : "added", hours,
3205 (hours == 1) ? "r" : "rs", minutes, (minutes == 1) ? "e" : "es",
3206 seconds, (seconds == 1) ? ")" : "s)");
3215 /*********************************************************************
3217 * Function : client_if_none_match
3219 * Description : Remove the If-None-Match header.
3222 * 1 : csp = Current client state (buffers, headers, etc...)
3223 * 2 : header = On input, pointer to header to modify.
3224 * On output, pointer to the modified header, or NULL
3225 * to remove the header. This function frees the
3226 * original string if necessary.
3228 * Returns : JB_ERR_OK on success, or
3229 * JB_ERR_MEMORY on out-of-memory error.
3231 *********************************************************************/
3232 static jb_err client_if_none_match(struct client_state *csp, char **header)
3234 if (csp->action->flags & ACTION_CRUNCH_IF_NONE_MATCH)
3236 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3244 /*********************************************************************
3246 * Function : client_x_filter
3248 * Description : Disables filtering if the client set "X-Filter: No".
3249 * Called from `sed'.
3252 * 1 : csp = Current client state (buffers, headers, etc...)
3253 * 2 : header = On input, pointer to header to modify.
3254 * On output, pointer to the modified header, or NULL
3255 * to remove the header. This function frees the
3256 * original string if necessary.
3258 * Returns : JB_ERR_OK on success
3260 *********************************************************************/
3261 jb_err client_x_filter(struct client_state *csp, char **header)
3263 if ( 0 == strcmpic(*header, "X-Filter: No"))
3265 if (!(csp->config->feature_flags & RUNTIME_FEATURE_HTTP_TOGGLE))
3267 log_error(LOG_LEVEL_INFO, "Ignored the client's request to fetch without filtering.");
3271 if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
3273 log_error(LOG_LEVEL_HEADER,
3274 "force-text-mode overruled the client's request to fetch without filtering!");
3278 csp->content_type = CT_TABOO; /* XXX: This hack shouldn't be necessary */
3279 csp->flags |= CSP_FLAG_NO_FILTERING;
3280 log_error(LOG_LEVEL_HEADER, "Accepted the client's request to fetch without filtering.");
3282 log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3290 /*********************************************************************
3292 * Function : client_range
3294 * Description : Removes Range, Request-Range and If-Range headers if
3295 * content filtering is enabled. If the client's version
3296 * of the document has been altered by Privoxy, the server
3297 * could interpret the range differently than the client
3298 * intended in which case the user could end up with
3299 * corrupted content.
3302 * 1 : csp = Current client state (buffers, headers, etc...)
3303 * 2 : header = On input, pointer to header to modify.
3304 * On output, pointer to the modified header, or NULL
3305 * to remove the header. This function frees the
3306 * original string if necessary.
3308 * Returns : JB_ERR_OK
3310 *********************************************************************/
3311 static jb_err client_range(struct client_state *csp, char **header)
3313 if (content_filters_enabled(csp->action))
3315 log_error(LOG_LEVEL_HEADER, "Content filtering is enabled."
3316 " Crunching: \'%s\' to prevent range-mismatch problems.", *header);
3323 /* the following functions add headers directly to the header list */
3325 /*********************************************************************
3327 * Function : client_host_adder
3329 * Description : Adds the Host: header field if it is missing.
3330 * Called from `sed'.
3333 * 1 : csp = Current client state (buffers, headers, etc...)
3335 * Returns : JB_ERR_OK on success, or
3336 * JB_ERR_MEMORY on out-of-memory error.
3338 *********************************************************************/
3339 static jb_err client_host_adder(struct client_state *csp)
3344 if (csp->flags & CSP_FLAG_HOST_HEADER_IS_SET)
3346 /* Header already set by the client, nothing to do. */
3350 if ( !csp->http->hostport || !*(csp->http->hostport))
3352 /* XXX: When does this happen and why is it OK? */
3353 log_error(LOG_LEVEL_INFO, "Weirdness in client_host_adder detected and ignored.");
3358 * remove 'user:pass@' from 'proto://user:pass@host'
3360 if ( (p = strchr( csp->http->hostport, '@')) != NULL )
3366 p = csp->http->hostport;
3369 /* XXX: Just add it, we already made sure that it will be unique */
3370 log_error(LOG_LEVEL_HEADER, "addh-unique: Host: %s", p);
3371 err = enlist_unique_header(csp->headers, "Host", p);
3378 /*********************************************************************
3380 * Function : client_accept_encoding_adder
3382 * Description : Add an Accept-Encoding header to the client's request
3383 * that disables compression if the action applies, and
3384 * the header is not already there. Called from `sed'.
3385 * Note: For HTTP/1.0, the absence of the header is enough.
3388 * 1 : csp = Current client state (buffers, headers, etc...)
3390 * Returns : JB_ERR_OK on success, or
3391 * JB_ERR_MEMORY on out-of-memory error.
3393 *********************************************************************/
3394 static jb_err client_accept_encoding_adder(struct client_state *csp)
3396 if ( ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
3397 && (!strcmpic(csp->http->ver, "HTTP/1.1")) )
3399 return enlist_unique(csp->headers, "Accept-Encoding: identity;q=1.0, *;q=0", 16);
3407 /*********************************************************************
3409 * Function : client_xtra_adder
3411 * Description : Used in the add_client_headers list. Called from `sed'.
3414 * 1 : csp = Current client state (buffers, headers, etc...)
3416 * Returns : JB_ERR_OK on success, or
3417 * JB_ERR_MEMORY on out-of-memory error.
3419 *********************************************************************/
3420 static jb_err client_xtra_adder(struct client_state *csp)
3422 struct list_entry *lst;
3425 for (lst = csp->action->multi[ACTION_MULTI_ADD_HEADER]->first;
3426 lst ; lst = lst->next)
3428 log_error(LOG_LEVEL_HEADER, "addh: %s", lst->str);
3429 err = enlist(csp->headers, lst->str);
3441 /*********************************************************************
3443 * Function : client_x_forwarded_for_adder
3445 * Description : Used in the add_client_headers list. Called from `sed'.
3448 * 1 : csp = Current client state (buffers, headers, etc...)
3450 * Returns : JB_ERR_OK on success, or
3451 * JB_ERR_MEMORY on out-of-memory error.
3453 *********************************************************************/
3454 static jb_err client_x_forwarded_for_adder(struct client_state *csp)
3456 char *header = NULL;
3459 if (!((csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR)
3460 && (0 == strcmpic(csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR], "add")))
3461 || (csp->flags & CSP_FLAG_X_FORWARDED_FOR_APPENDED))
3464 * If we aren't adding X-Forwarded-For headers,
3465 * or we already appended an existing X-Forwarded-For
3466 * header, there's nothing left to do here.
3471 header = strdup("X-Forwarded-For: ");
3472 string_append(&header, csp->ip_addr_str);
3476 return JB_ERR_MEMORY;
3479 log_error(LOG_LEVEL_HEADER, "addh: %s", header);
3480 err = enlist(csp->headers, header);
3487 /*********************************************************************
3489 * Function : server_connection_adder
3491 * Description : Adds an appropiate "Connection:" header to csp->headers
3492 * unless the header was already present. Called from `sed'.
3495 * 1 : csp = Current client state (buffers, headers, etc...)
3497 * Returns : JB_ERR_OK on success, or
3498 * JB_ERR_MEMORY on out-of-memory error.
3500 *********************************************************************/
3501 static jb_err server_connection_adder(struct client_state *csp)
3503 const unsigned int flags = csp->flags;
3504 const char *response_status_line = csp->headers->first->str;
3505 static const char connection_close[] = "Connection: close";
3507 if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
3508 && (flags & CSP_FLAG_SERVER_CONNECTION_HEADER_SET))
3514 * XXX: if we downgraded the response, this check will fail.
3516 if ((csp->config->feature_flags &
3517 RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
3518 && (NULL != response_status_line)
3519 && !strncmpic(response_status_line, "HTTP/1.1", 8)
3520 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3521 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
3525 log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
3526 "without Connection header implies keep-alive.");
3527 csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
3531 log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
3533 return enlist(csp->headers, connection_close);
3537 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3538 /*********************************************************************
3540 * Function : server_proxy_connection_adder
3542 * Description : Adds a "Proxy-Connection: keep-alive" header to
3543 * csp->headers if the client asked for keep-alive.
3544 * XXX: We should reuse existant ones.
3547 * 1 : csp = Current client state (buffers, headers, etc...)
3549 * Returns : JB_ERR_OK on success, or
3550 * JB_ERR_MEMORY on out-of-memory error.
3552 *********************************************************************/
3553 static jb_err server_proxy_connection_adder(struct client_state *csp)
3555 static const char proxy_connection_header[] = "Proxy-Connection: keep-alive";
3556 jb_err err = JB_ERR_OK;
3558 if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
3559 && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
3560 && !(csp->flags & CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET))
3562 log_error(LOG_LEVEL_HEADER, "Adding: %s", proxy_connection_header);
3563 err = enlist(csp->headers, proxy_connection_header);
3568 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
3571 /*********************************************************************
3573 * Function : client_connection_header_adder
3575 * Description : Adds a proper "Connection:" header to csp->headers
3576 * unless the header was already present. Called from `sed'.
3579 * 1 : csp = Current client state (buffers, headers, etc...)
3581 * Returns : JB_ERR_OK on success, or
3582 * JB_ERR_MEMORY on out-of-memory error.
3584 *********************************************************************/
3585 static jb_err client_connection_header_adder(struct client_state *csp)
3587 static const char connection_close[] = "Connection: close";
3589 if (!(csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
3590 && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET))
3595 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3596 if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
3597 && (csp->http->ssl == 0)
3598 && !strcmpic(csp->http->ver, "HTTP/1.1"))
3600 csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
3603 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
3605 log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
3607 return enlist(csp->headers, connection_close);
3611 /*********************************************************************
3613 * Function : server_http
3615 * Description : - Save the HTTP Status into csp->http->status
3616 * - Set CT_TABOO to prevent filtering if the answer
3617 * is a partial range (HTTP status 206)
3618 * - Rewrite HTTP/1.1 answers to HTTP/1.0 if +downgrade
3622 * 1 : csp = Current client state (buffers, headers, etc...)
3623 * 2 : header = On input, pointer to header to modify.
3624 * On output, pointer to the modified header, or NULL
3625 * to remove the header. This function frees the
3626 * original string if necessary.
3628 * Returns : JB_ERR_OK on success, or
3629 * JB_ERR_MEMORY on out-of-memory error.
3631 *********************************************************************/
3632 static jb_err server_http(struct client_state *csp, char **header)
3634 sscanf(*header, "HTTP/%*d.%*d %d", &(csp->http->status));
3635 if (csp->http->status == 206)
3637 csp->content_type = CT_TABOO;
3640 if ((csp->action->flags & ACTION_DOWNGRADE) != 0)
3642 /* XXX: Should we do a real validity check here? */
3643 if (strlen(*header) > 8)
3646 log_error(LOG_LEVEL_HEADER, "Downgraded answer to HTTP/1.0");
3651 * XXX: Should we block the request or
3652 * enlist a valid status code line here?
3654 log_error(LOG_LEVEL_INFO, "Malformed server response detected. "
3655 "Downgrading to HTTP/1.0 impossible.");
3663 /*********************************************************************
3665 * Function : server_set_cookie
3667 * Description : Handle the server "cookie" header properly.
3668 * Crunch, accept or rewrite it to a session cookie.
3669 * Called from `sed'.
3671 * TODO: Allow the user to specify a new expiration
3672 * time to cause the cookie to expire even before the
3673 * browser is closed.
3676 * 1 : csp = Current client state (buffers, headers, etc...)
3677 * 2 : header = On input, pointer to header to modify.
3678 * On output, pointer to the modified header, or NULL
3679 * to remove the header. This function frees the
3680 * original string if necessary.
3682 * Returns : JB_ERR_OK on success, or
3683 * JB_ERR_MEMORY on out-of-memory error.
3685 *********************************************************************/
3686 static jb_err server_set_cookie(struct client_state *csp, char **header)
3693 if ((csp->action->flags & ACTION_NO_COOKIE_SET) != 0)
3695 log_error(LOG_LEVEL_HEADER, "Crunching incoming cookie: %s", *header);
3698 else if ((csp->action->flags & ACTION_NO_COOKIE_KEEP) != 0)
3700 /* Flag whether or not to log a message */
3703 /* A variable to store the tag we're working on */
3706 /* Skip "Set-Cookie:" (11 characters) in header */
3707 cur_tag = *header + 11;
3709 /* skip whitespace between "Set-Cookie:" and value */
3710 while (*cur_tag && ijb_isspace(*cur_tag))
3715 /* Loop through each tag in the cookie */
3719 char *next_tag = strchr(cur_tag, ';');
3720 if (next_tag != NULL)
3722 /* Skip the ';' character itself */
3725 /* skip whitespace ";" and start of tag */
3726 while (*next_tag && ijb_isspace(*next_tag))
3733 /* "Next tag" is the end of the string */
3734 next_tag = cur_tag + strlen(cur_tag);
3738 * Check the expiration date to see
3739 * if the cookie is still valid, if yes,
3740 * rewrite it to a session cookie.
3742 if ((strncmpic(cur_tag, "expires=", 8) == 0) && *(cur_tag + 8))
3744 char *expiration_date = cur_tag + 8; /* Skip "[Ee]xpires=" */
3746 /* Did we detect the date properly? */
3747 if (JB_ERR_OK != parse_header_time(expiration_date, &cookie_time))
3750 * Nope, treat it as if it was still valid.
3752 * XXX: Should we remove the whole cookie instead?
3754 log_error(LOG_LEVEL_ERROR,
3755 "Can't parse \'%s\', send by %s. Unsupported time format?", cur_tag, csp->http->url);
3756 string_move(cur_tag, next_tag);
3762 * Yes. Check if the cookie is still valid.
3764 * If the cookie is already expired it's probably
3765 * a delete cookie and even if it isn't, the browser
3766 * will discard it anyway.
3770 * XXX: timegm() isn't available on some AmigaOS
3771 * versions and our replacement doesn't work.
3773 * Our options are to either:
3775 * - disable session-cookies-only completely if timegm
3778 * - to simply remove all expired tags, like it has
3779 * been done until Privoxy 3.0.6 and to live with
3780 * the consequence that it can cause login/logout
3781 * problems on servers that don't validate their
3782 * input properly, or
3784 * - to replace it with mktime in which
3785 * case there is a slight chance of valid cookies
3786 * passing as already expired.
3788 * This is the way it's currently done and it's not
3789 * as bad as it sounds. If the missing GMT offset is
3790 * enough to change the result of the expiration check
3791 * the cookie will be only valid for a few hours
3792 * anyway, which in many cases will be shorter
3793 * than a browser session.
3795 if (cookie_time - now < 0)
3797 log_error(LOG_LEVEL_HEADER,
3798 "Cookie \'%s\' is already expired and can pass unmodified.", *header);
3799 /* Just in case some clown sets more then one expiration date */
3805 * Still valid, delete expiration date by copying
3806 * the rest of the string over it.
3808 string_move(cur_tag, next_tag);
3810 /* That changed the header, need to issue a log message */
3814 * Note that the next tag has now been moved to *cur_tag,
3815 * so we do not need to update the cur_tag pointer.
3823 /* Move on to next cookie tag */
3830 assert(NULL != *header);
3831 log_error(LOG_LEVEL_HEADER, "Cookie rewritten to a temporary one: %s",
3840 #ifdef FEATURE_FORCE_LOAD
3841 /*********************************************************************
3843 * Function : strclean
3845 * Description : In-Situ-Eliminate all occurances of substring in
3849 * 1 : string = string to clean
3850 * 2 : substring = substring to eliminate
3852 * Returns : Number of eliminations
3854 *********************************************************************/
3855 int strclean(char *string, const char *substring)
3861 len = strlen(substring);
3863 while((pos = strstr(string, substring)) != NULL)
3870 while (*p++ != '\0');
3877 #endif /* def FEATURE_FORCE_LOAD */
3880 /*********************************************************************
3882 * Function : parse_header_time
3884 * Description : Parses time formats used in HTTP header strings
3885 * to get the numerical respresentation.
3888 * 1 : header_time = HTTP header time as string.
3889 * 2 : result = storage for header_time in seconds
3891 * Returns : JB_ERR_OK if the time format was recognized, or
3892 * JB_ERR_PARSE otherwise.
3894 *********************************************************************/
3895 static jb_err parse_header_time(const char *header_time, time_t *result)
3900 * Zero out gmt to prevent time zone offsets.
3902 * While this is only necessary on some platforms
3903 * (mingw32 for example), I don't know how to
3904 * detect these automatically and doing it everywhere
3907 memset(&gmt, 0, sizeof(gmt));
3909 /* Tue, 02 Jun 2037 20:00:00 */
3910 if ((NULL == strptime(header_time, "%a, %d %b %Y %H:%M:%S", &gmt))
3911 /* Tue, 02-Jun-2037 20:00:00 */
3912 && (NULL == strptime(header_time, "%a, %d-%b-%Y %H:%M:%S", &gmt))
3913 /* Tue, 02-Jun-37 20:00:00 */
3914 && (NULL == strptime(header_time, "%a, %d-%b-%y %H:%M:%S", &gmt))
3915 /* Tuesday, 02-Jun-2037 20:00:00 */
3916 && (NULL == strptime(header_time, "%A, %d-%b-%Y %H:%M:%S", &gmt))
3917 /* Tuesday Jun 02 20:00:00 2037 */
3918 && (NULL == strptime(header_time, "%A %b %d %H:%M:%S %Y", &gmt)))
3920 return JB_ERR_PARSE;
3923 *result = timegm(&gmt);
3930 /*********************************************************************
3932 * Function : get_destination_from_headers
3934 * Description : Parse the "Host:" header to get the request's destination.
3935 * Only needed if the client's request was forcefully
3936 * redirected into Privoxy.
3938 * Code mainly copied from client_host() which is currently
3939 * run too late for this purpose.
3942 * 1 : headers = List of headers (one of them hopefully being
3943 * the "Host:" header)
3944 * 2 : http = storage for the result (host, port and hostport).
3946 * Returns : JB_ERR_MEMORY in case of memory problems,
3947 * JB_ERR_PARSE if the host header couldn't be found,
3948 * JB_ERR_OK otherwise.
3950 *********************************************************************/
3951 jb_err get_destination_from_headers(const struct list *headers, struct http_request *http)
3957 host = get_header_value(headers, "Host:");
3961 log_error(LOG_LEVEL_ERROR, "No \"Host:\" header found.");
3962 return JB_ERR_PARSE;
3965 if (NULL == (p = strdup((host))))
3967 log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
3968 return JB_ERR_MEMORY;
3971 if (NULL == (q = strdup(p)))
3974 log_error(LOG_LEVEL_ERROR, "Out of memory while parsing \"Host:\" header");
3975 return JB_ERR_MEMORY;
3978 freez(http->hostport);
3982 q = strchr(http->host, ':');
3985 /* Terminate hostname and evaluate port string */
3987 http->port = atoi(q);
3991 http->port = http->ssl ? 443 : 80;
3994 /* Rebuild request URL */
3996 http->url = strdup(http->ssl ? "https://" : "http://");
3997 string_append(&http->url, http->hostport);
3998 string_append(&http->url, http->path);
3999 if (http->url == NULL)
4001 return JB_ERR_MEMORY;
4004 log_error(LOG_LEVEL_HEADER, "Destination extracted from \"Host:\" header. New request URL: %s",
4012 /*********************************************************************
4014 * Function : create_forged_referrer
4016 * Description : Helper for client_referrer to forge a referer as
4017 * 'http://[hostname:port/' to fool stupid
4018 * checks for in-site links
4021 * 1 : header = Pointer to header pointer
4022 * 2 : hostport = Host and optionally port as string
4024 * Returns : JB_ERR_OK in case of success, or
4025 * JB_ERR_MEMORY in case of memory problems.
4027 *********************************************************************/
4028 static jb_err create_forged_referrer(char **header, const char *hostport)
4030 assert(NULL == *header);
4032 *header = strdup("Referer: http://");
4033 string_append(header, hostport);
4034 string_append(header, "/");
4036 if (NULL == *header)
4038 return JB_ERR_MEMORY;
4041 log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
4048 /*********************************************************************
4050 * Function : create_fake_referrer
4052 * Description : Helper for client_referrer to create a fake referrer
4053 * based on a string supplied by the user.
4056 * 1 : header = Pointer to header pointer
4057 * 2 : hosthost = Referrer to fake
4059 * Returns : JB_ERR_OK in case of success, or
4060 * JB_ERR_MEMORY in case of memory problems.
4062 *********************************************************************/
4063 static jb_err create_fake_referrer(char **header, const char *fake_referrer)
4065 assert(NULL == *header);
4067 if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
4069 log_error(LOG_LEVEL_HEADER,
4070 "Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
4072 *header = strdup("Referer: ");
4073 string_append(header, fake_referrer);
4075 if (NULL == *header)
4077 return JB_ERR_MEMORY;
4080 log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
4087 /*********************************************************************
4089 * Function : handle_conditional_hide_referrer_parameter
4091 * Description : Helper for client_referrer to crunch or forge
4092 * the referrer header if the host has changed.
4095 * 1 : header = Pointer to header pointer
4096 * 2 : host = The target host (may include the port)
4097 * 3 : parameter_conditional_block = Boolean to signal
4098 * if we're in conditional-block mode. If not set,
4099 * we're in conditional-forge mode.
4101 * Returns : JB_ERR_OK in case of success, or
4102 * JB_ERR_MEMORY in case of memory problems.
4104 *********************************************************************/
4105 static jb_err handle_conditional_hide_referrer_parameter(char **header,
4106 const char *host, const int parameter_conditional_block)
4108 char *referer = strdup(*header);
4109 const size_t hostlenght = strlen(host);
4110 const char *referer_url = NULL;
4112 if (NULL == referer)
4115 return JB_ERR_MEMORY;
4118 /* referer begins with 'Referer: http[s]://' */
4119 if ((hostlenght+17) < strlen(referer))
4122 * Shorten referer to make sure the referer is blocked
4123 * if www.example.org/www.example.com-shall-see-the-referer/
4124 * links to www.example.com/
4126 referer[hostlenght+17] = '\0';
4128 referer_url = strstr(referer, "http://");
4129 if ((NULL == referer_url) || (NULL == strstr(referer_url, host)))
4131 /* Host has changed, Referer is invalid or a https URL. */
4132 if (parameter_conditional_block)
4134 log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
4141 return create_forged_referrer(header, host);
4151 /*********************************************************************
4153 * Function : create_content_length_header
4155 * Description : Creates a Content-Length header.
4158 * 1 : content_length = The content length to be used in the header.
4159 * 2 : header = Allocated space to safe the header.
4160 * 3 : buffer_length = The length of the allocated space.
4164 *********************************************************************/
4165 static void create_content_length_header(unsigned long long content_length,
4166 char *header, size_t buffer_length)
4168 snprintf(header, buffer_length, "Content-Length: %llu", content_length);