Line data Source code
1 : /*********************************************************************
2 : *
3 : * File : $Source: /cvsroot/ijbswa/current/parsers.c,v $
4 : *
5 : * Purpose : Declares functions to parse/crunch headers and pages.
6 : *
7 : * Copyright : Written by and Copyright (C) 2001-2021 the
8 : * Privoxy team. https://www.privoxy.org/
9 : *
10 : * Based on the Internet Junkbuster originally written
11 : * by and Copyright (C) 1997 Anonymous Coders and
12 : * Junkbusters Corporation. http://www.junkbusters.com
13 : *
14 : * This program is free software; you can redistribute it
15 : * and/or modify it under the terms of the GNU General
16 : * Public License as published by the Free Software
17 : * Foundation; either version 2 of the License, or (at
18 : * your option) any later version.
19 : *
20 : * This program is distributed in the hope that it will
21 : * be useful, but WITHOUT ANY WARRANTY; without even the
22 : * implied warranty of MERCHANTABILITY or FITNESS FOR A
23 : * PARTICULAR PURPOSE. See the GNU General Public
24 : * License for more details.
25 : *
26 : * The GNU General Public License should be included with
27 : * this file. If not, you can view it at
28 : * http://www.gnu.org/copyleft/gpl.html
29 : * or write to the Free Software Foundation, Inc., 59
30 : * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
31 : *
32 : *********************************************************************/
33 :
34 :
35 : #include "config.h"
36 :
37 : #ifndef _WIN32
38 : #include <stdio.h>
39 : #include <sys/types.h>
40 : #endif
41 :
42 : #include <stdlib.h>
43 : #include <ctype.h>
44 : #include <assert.h>
45 : #include <string.h>
46 :
47 : #ifdef __GLIBC__
48 : /*
49 : * Convince GNU's libc to provide a strptime prototype.
50 : */
51 : #define __USE_XOPEN
52 : #endif /*__GLIBC__ */
53 : #include <time.h>
54 :
55 : #ifdef FEATURE_ZLIB
56 : #include <zlib.h>
57 :
58 : #define GZIP_IDENTIFIER_1 0x1f
59 : #define GZIP_IDENTIFIER_2 0x8b
60 :
61 : #define GZIP_FLAG_CHECKSUM 0x02
62 : #define GZIP_FLAG_EXTRA_FIELDS 0x04
63 : #define GZIP_FLAG_FILE_NAME 0x08
64 : #define GZIP_FLAG_COMMENT 0x10
65 : #define GZIP_FLAG_RESERVED_BITS 0xe0
66 : #endif
67 : #ifdef FEATURE_BROTLI
68 : #include <brotli/decode.h>
69 : #endif
70 :
71 : #if !defined(_WIN32)
72 : #include <unistd.h>
73 : #endif
74 :
75 : #include "project.h"
76 :
77 : #ifdef FEATURE_PTHREAD
78 : #include "jcc.h"
79 : /* jcc.h is for mutex semapores only */
80 : #endif /* def FEATURE_PTHREAD */
81 : #include "list.h"
82 : #include "parsers.h"
83 : #include "ssplit.h"
84 : #include "errlog.h"
85 : #include "jbsockets.h"
86 : #include "miscutil.h"
87 : #include "list.h"
88 : #include "actions.h"
89 : #include "filters.h"
90 : #ifdef FEATURE_HTTPS_INSPECTION
91 : #include "ssl.h"
92 : #endif
93 :
94 : #ifndef HAVE_STRPTIME
95 : #include "strptime.h"
96 : #endif
97 :
98 : static char *get_header_line(struct iob *iob);
99 : static jb_err scan_headers(struct client_state *csp);
100 : static jb_err header_tagger(struct client_state *csp, char *header);
101 : static jb_err parse_header_time(const char *header_time, time_t *result);
102 : static jb_err parse_time_header(const char *header, time_t *result);
103 :
104 : static jb_err crumble (struct client_state *csp, char **header);
105 : static jb_err filter_header (struct client_state *csp, char **header);
106 : static jb_err client_connection (struct client_state *csp, char **header);
107 : static jb_err client_referrer (struct client_state *csp, char **header);
108 : static jb_err client_uagent (struct client_state *csp, char **header);
109 : static jb_err client_ua (struct client_state *csp, char **header);
110 : static jb_err client_from (struct client_state *csp, char **header);
111 : static jb_err client_send_cookie (struct client_state *csp, char **header);
112 : static jb_err client_x_forwarded (struct client_state *csp, char **header);
113 : static jb_err client_accept_encoding (struct client_state *csp, char **header);
114 : static jb_err client_te (struct client_state *csp, char **header);
115 : static jb_err client_max_forwards (struct client_state *csp, char **header);
116 : static jb_err client_host (struct client_state *csp, char **header);
117 : static jb_err client_if_modified_since (struct client_state *csp, char **header);
118 : static jb_err client_accept_language (struct client_state *csp, char **header);
119 : static jb_err client_if_none_match (struct client_state *csp, char **header);
120 : static jb_err crunch_client_header (struct client_state *csp, char **header);
121 : static jb_err client_x_filter (struct client_state *csp, char **header);
122 : static jb_err client_range (struct client_state *csp, char **header);
123 : static jb_err client_expect (struct client_state *csp, char **header);
124 : static jb_err server_set_cookie (struct client_state *csp, char **header);
125 : static jb_err server_connection (struct client_state *csp, char **header);
126 : static jb_err server_content_type (struct client_state *csp, char **header);
127 : static jb_err server_adjust_content_length(struct client_state *csp, char **header);
128 : static jb_err server_content_md5 (struct client_state *csp, char **header);
129 : static jb_err server_content_encoding (struct client_state *csp, char **header);
130 : static jb_err server_transfer_coding (struct client_state *csp, char **header);
131 : static jb_err server_http (struct client_state *csp, char **header);
132 : static jb_err crunch_server_header (struct client_state *csp, char **header);
133 : static jb_err server_last_modified (struct client_state *csp, char **header);
134 : static jb_err server_content_disposition(struct client_state *csp, char **header);
135 : #ifdef FEATURE_ZLIB
136 : static jb_err server_adjust_content_encoding(struct client_state *csp, char **header);
137 : #endif
138 :
139 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
140 : static jb_err server_save_content_length(struct client_state *csp, char **header);
141 : static jb_err server_keep_alive(struct client_state *csp, char **header);
142 : static jb_err server_proxy_connection(struct client_state *csp, char **header);
143 : static jb_err client_keep_alive(struct client_state *csp, char **header);
144 : static jb_err client_proxy_connection(struct client_state *csp, char **header);
145 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
146 :
147 : static jb_err client_save_content_length(struct client_state *csp, char **header);
148 : static jb_err client_host_adder (struct client_state *csp);
149 : static jb_err client_xtra_adder (struct client_state *csp);
150 : static jb_err client_x_forwarded_for_adder(struct client_state *csp);
151 : static jb_err client_connection_header_adder(struct client_state *csp);
152 : static jb_err server_connection_adder(struct client_state *csp);
153 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
154 : static jb_err server_proxy_connection_adder(struct client_state *csp);
155 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
156 : static jb_err proxy_authentication(struct client_state *csp, char **header);
157 :
158 : static jb_err create_forged_referrer(char **header, const char *hostport);
159 : static jb_err create_fake_referrer(char **header, const char *fake_referrer);
160 : static jb_err handle_conditional_hide_referrer_parameter(char **header,
161 : const char *host, const int parameter_conditional_block);
162 : static void create_content_length_header(unsigned long long content_length,
163 : char *header, size_t buffer_length);
164 :
165 : /*
166 : * List of functions to run on a list of headers.
167 : */
168 : struct parsers
169 : {
170 : /** The header prefix to match */
171 : const char *str;
172 :
173 : /** The length of the prefix to match */
174 : const size_t len;
175 :
176 : /** The function to apply to this line */
177 : const parser_func_ptr parser;
178 : };
179 :
180 : static const struct parsers client_patterns[] = {
181 : { "referer:", 8, client_referrer },
182 : { "user-agent:", 11, client_uagent },
183 : { "ua-", 3, client_ua },
184 : { "from:", 5, client_from },
185 : { "cookie:", 7, client_send_cookie },
186 : { "x-forwarded-for:", 16, client_x_forwarded },
187 : { "Accept-Encoding:", 16, client_accept_encoding },
188 : { "TE:", 3, client_te },
189 : { "Host:", 5, client_host },
190 : { "if-modified-since:", 18, client_if_modified_since },
191 : { "Content-Length:", 15, client_save_content_length },
192 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
193 : { "Keep-Alive:", 11, client_keep_alive },
194 : { "Proxy-Connection:", 17, client_proxy_connection },
195 : #else
196 : { "Keep-Alive:", 11, crumble },
197 : { "Proxy-Connection:", 17, crumble },
198 : #endif
199 : { "connection:", 11, client_connection },
200 : { "max-forwards:", 13, client_max_forwards },
201 : { "Accept-Language:", 16, client_accept_language },
202 : { "if-none-match:", 14, client_if_none_match },
203 : { "Range:", 6, client_range },
204 : { "Request-Range:", 14, client_range },
205 : { "If-Range:", 9, client_range },
206 : { "X-Filter:", 9, client_x_filter },
207 : { "Proxy-Authorization:", 20, proxy_authentication },
208 : #if 0
209 : { "Transfer-Encoding:", 18, client_transfer_encoding },
210 : #endif
211 : { "Expect:", 7, client_expect },
212 : { "*", 0, crunch_client_header },
213 : { "*", 0, filter_header },
214 : { NULL, 0, NULL }
215 : };
216 :
217 : static const struct parsers server_patterns[] = {
218 : { "HTTP/", 5, server_http },
219 : { "set-cookie:", 11, server_set_cookie },
220 : { "connection:", 11, server_connection },
221 : { "Content-Type:", 13, server_content_type },
222 : { "Content-MD5:", 12, server_content_md5 },
223 : { "Content-Encoding:", 17, server_content_encoding },
224 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
225 : { "Content-Length:", 15, server_save_content_length },
226 : { "Keep-Alive:", 11, server_keep_alive },
227 : { "Proxy-Connection:", 17, server_proxy_connection },
228 : #else
229 : { "Keep-Alive:", 11, crumble },
230 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
231 : { "Transfer-Encoding:", 18, server_transfer_coding },
232 : { "content-disposition:", 20, server_content_disposition },
233 : { "Last-Modified:", 14, server_last_modified },
234 : { "Proxy-Authenticate:", 19, proxy_authentication },
235 : { "*", 0, crunch_server_header },
236 : { "*", 0, filter_header },
237 : { NULL, 0, NULL }
238 : };
239 :
240 : static const add_header_func_ptr add_client_headers[] = {
241 : client_host_adder,
242 : client_x_forwarded_for_adder,
243 : client_xtra_adder,
244 : client_connection_header_adder,
245 : NULL
246 : };
247 :
248 : static const add_header_func_ptr add_server_headers[] = {
249 : server_connection_adder,
250 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
251 : server_proxy_connection_adder,
252 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
253 : NULL
254 : };
255 :
256 : /*********************************************************************
257 : *
258 : * Function : flush_iob
259 : *
260 : * Description : Write any pending "buffered" content.
261 : *
262 : * Parameters :
263 : * 1 : fd = file descriptor of the socket to read
264 : * 2 : iob = The I/O buffer to flush, usually csp->iob.
265 : * 3 : delay = Number of milliseconds to delay the writes
266 : *
267 : * Returns : On success, the number of bytes written are returned (zero
268 : * indicates nothing was written). On error, -1 is returned,
269 : * and errno is set appropriately. If count is zero and the
270 : * file descriptor refers to a regular file, 0 will be
271 : * returned without causing any other effect. For a special
272 : * file, the results are not portable.
273 : *
274 : *********************************************************************/
275 7414 : long flush_iob(jb_socket fd, struct iob *iob, unsigned int delay)
276 : {
277 7414 : long len = iob->eod - iob->cur;
278 :
279 7414 : if (len <= 0)
280 : {
281 5747 : return(0);
282 : }
283 :
284 1667 : if (write_socket_delayed(fd, iob->cur, (size_t)len, delay))
285 : {
286 0 : return(-1);
287 : }
288 1667 : iob->eod = iob->cur = iob->buf;
289 1667 : return(len);
290 :
291 : }
292 :
293 :
294 : /*********************************************************************
295 : *
296 : * Function : can_add_to_iob
297 : *
298 : * Description : Checks if the given number of bytes can be added to the given iob
299 : * without exceeding the given buffer limit.
300 : *
301 : * Parameters :
302 : * 1 : iob = Destination buffer.
303 : * 2 : buffer_limit = Limit to which the destination may grow
304 : * 3 : n = number of bytes to be added
305 : *
306 : * Returns : TRUE if the given iob can handle given number of bytes
307 : * FALSE buffer limit will be exceeded
308 : *
309 : *********************************************************************/
310 926 : int can_add_to_iob(const struct iob *iob, const size_t buffer_limit, size_t n)
311 : {
312 926 : return ((size_t)(iob->eod - iob->buf) + n + 1) > buffer_limit ? FALSE : TRUE;
313 : }
314 :
315 : /*********************************************************************
316 : *
317 : * Function : add_to_iob
318 : *
319 : * Description : Add content to the buffer, expanding the
320 : * buffer if necessary.
321 : *
322 : * Parameters :
323 : * 1 : iob = Destination buffer.
324 : * 2 : buffer_limit = Limit to which the destination may grow
325 : * 3 : src = holds the content to be added
326 : * 4 : n = number of bytes to be added
327 : *
328 : * Returns : JB_ERR_OK on success, JB_ERR_MEMORY if out-of-memory
329 : * or buffer limit reached.
330 : *
331 : *********************************************************************/
332 51226 : jb_err add_to_iob(struct iob *iob, const size_t buffer_limit, const char *src, long n)
333 : {
334 : size_t used, offset, need;
335 : char *p;
336 :
337 51226 : if (n <= 0) return JB_ERR_OK;
338 :
339 51017 : used = (size_t)(iob->eod - iob->buf);
340 51017 : offset = (size_t)(iob->cur - iob->buf);
341 51017 : need = used + (size_t)n + 1;
342 :
343 : /*
344 : * If the buffer can't hold the new data, extend it first.
345 : * Use the next power of two if possible, else use the actual need.
346 : */
347 51017 : if (need > buffer_limit)
348 : {
349 0 : log_error(LOG_LEVEL_INFO,
350 : "Buffer limit reached while extending the buffer (iob). Needed: %lu. Limit: %lu",
351 : need, buffer_limit);
352 0 : return JB_ERR_MEMORY;
353 : }
354 :
355 51017 : if (need > iob->size)
356 : {
357 32837 : size_t want = iob->size ? iob->size : 512;
358 :
359 49070 : while (want <= need)
360 : {
361 16233 : want *= 2;
362 : }
363 :
364 32837 : if (want <= buffer_limit && NULL != (p = (char *)realloc(iob->buf, want)))
365 : {
366 32837 : iob->size = want;
367 : }
368 0 : else if (NULL != (p = (char *)realloc(iob->buf, need)))
369 : {
370 0 : iob->size = need;
371 : }
372 : else
373 : {
374 0 : log_error(LOG_LEVEL_ERROR, "Extending the buffer (iob) failed: %E");
375 0 : return JB_ERR_MEMORY;
376 : }
377 :
378 : /* Update the iob pointers */
379 32837 : iob->cur = p + offset;
380 32837 : iob->eod = p + used;
381 32837 : iob->buf = p;
382 : }
383 :
384 : /* copy the new data into the iob buffer */
385 51017 : memcpy(iob->eod, src, (size_t)n);
386 :
387 : /* point to the end of the data */
388 51017 : iob->eod += n;
389 :
390 : /* null terminate == cheap insurance */
391 51017 : *iob->eod = '\0';
392 :
393 51017 : return JB_ERR_OK;
394 :
395 : }
396 :
397 :
398 : /*********************************************************************
399 : *
400 : * Function : clear_iob
401 : *
402 : * Description : Frees the memory allocated for an I/O buffer and
403 : * resets the structure.
404 : *
405 : * Parameters :
406 : * 1 : iob = I/O buffer to clear.
407 : *
408 : * Returns : N/A
409 : *
410 : *********************************************************************/
411 50904 : void clear_iob(struct iob *iob)
412 : {
413 50904 : free(iob->buf);
414 50904 : memset(iob, '\0', sizeof(*iob));
415 50904 : }
416 :
417 :
418 : #ifdef FEATURE_ZLIB
419 : #ifdef FEATURE_BROTLI
420 : /*********************************************************************
421 : *
422 : * Function : decompress_iob_with_brotli
423 : *
424 : * Description : Decompress buffered page using Brotli.
425 : *
426 : * Parameters :
427 : * 1 : csp = Current client state (buffers, headers, etc...)
428 : *
429 : * Returns : JB_ERR_OK on success,
430 : * JB_ERR_MEMORY if out-of-memory limit reached, and
431 : * JB_ERR_COMPRESS if error decompressing buffer.
432 : *
433 : *********************************************************************/
434 19 : static jb_err decompress_iob_with_brotli(struct client_state *csp)
435 : {
436 : BrotliDecoderResult result;
437 : char *decoded_buffer;
438 : size_t decoded_size;
439 : size_t decoded_buffer_size;
440 : size_t encoded_size;
441 : enum { MAX_COMPRESSION_FACTOR = 15 };
442 :
443 19 : encoded_size = (size_t)(csp->iob->eod - csp->iob->cur);
444 : /*
445 : * The BrotliDecoderDecompress() api is a bit unfortunate
446 : * and requires the caller to reserve enough memory for
447 : * the decompressed content. Hopefully reserving
448 : * MAX_COMPRESSION_FACTOR times the original size is
449 : * sufficient. If not, BrotliDecoderDecompress() will fail.
450 : */
451 19 : decoded_buffer_size = encoded_size * MAX_COMPRESSION_FACTOR;
452 :
453 19 : if (decoded_buffer_size > csp->config->buffer_limit)
454 : {
455 0 : log_error(LOG_LEVEL_ERROR,
456 : "Buffer limit reached before decompressing iob with Brotli");
457 0 : return JB_ERR_MEMORY;
458 : }
459 :
460 19 : decoded_buffer = malloc(decoded_buffer_size);
461 19 : if (decoded_buffer == NULL)
462 : {
463 0 : log_error(LOG_LEVEL_ERROR,
464 : "Failed to allocate %lu bytes for Brotli decompression",
465 : decoded_buffer_size);
466 0 : return JB_ERR_MEMORY;
467 : }
468 :
469 19 : decoded_size = decoded_buffer_size;
470 19 : result = BrotliDecoderDecompress(encoded_size,
471 19 : (const uint8_t *)csp->iob->cur, &decoded_size,
472 : (uint8_t *)decoded_buffer);
473 19 : if (result == BROTLI_DECODER_RESULT_SUCCESS)
474 : {
475 : /*
476 : * Update the iob, since the decompression was successful.
477 : */
478 3 : freez(csp->iob->buf);
479 3 : csp->iob->buf = decoded_buffer;
480 3 : csp->iob->cur = csp->iob->buf;
481 3 : csp->iob->eod = csp->iob->cur + decoded_size;
482 3 : csp->iob->size = decoded_buffer_size;
483 :
484 3 : log_error(LOG_LEVEL_RE_FILTER,
485 : "Decompression successful. Old size: %lu, new size: %lu.",
486 : encoded_size, decoded_size);
487 :
488 3 : return JB_ERR_OK;
489 : }
490 : else
491 : {
492 16 : log_error(LOG_LEVEL_ERROR, "Failed to decompress buffer with Brotli");
493 16 : freez(decoded_buffer);
494 :
495 16 : return JB_ERR_COMPRESS;
496 : }
497 : }
498 : #endif
499 :
500 : /*********************************************************************
501 : *
502 : * Function : decompress_iob
503 : *
504 : * Description : Decompress buffered page, expanding the
505 : * buffer as necessary. csp->iob->cur
506 : * should point to the the beginning of the
507 : * compressed data block.
508 : *
509 : * Parameters :
510 : * 1 : csp = Current client state (buffers, headers, etc...)
511 : *
512 : * Returns : JB_ERR_OK on success,
513 : * JB_ERR_MEMORY if out-of-memory limit reached, and
514 : * JB_ERR_COMPRESS if error decompressing buffer.
515 : *
516 : *********************************************************************/
517 356 : jb_err decompress_iob(struct client_state *csp)
518 : {
519 : char *buf; /* new, uncompressed buffer */
520 : char *cur; /* Current iob position (to keep the original
521 : * iob->cur unmodified if we return early) */
522 : size_t bufsize; /* allocated size of the new buffer */
523 : size_t old_size; /* Content size before decompression */
524 : size_t skip_size; /* Number of bytes at the beginning of the iob
525 : that we should NOT decompress. */
526 : int status; /* return status of the inflate() call */
527 : z_stream zstr; /* used by calls to zlib */
528 :
529 : #ifdef FUZZ
530 356 : assert(csp->iob->cur - csp->iob->buf >= 0);
531 356 : assert(csp->iob->eod - csp->iob->cur >= 0);
532 : #else
533 : assert(csp->iob->cur - csp->iob->buf > 0);
534 : assert(csp->iob->eod - csp->iob->cur > 0);
535 : #endif
536 :
537 356 : bufsize = csp->iob->size;
538 356 : skip_size = (size_t)(csp->iob->cur - csp->iob->buf);
539 356 : old_size = (size_t)(csp->iob->eod - csp->iob->cur);
540 :
541 356 : cur = csp->iob->cur;
542 :
543 356 : if (old_size < (size_t)10)
544 : {
545 : /*
546 : * This is to protect the parsing of gzipped data,
547 : * but it should(?) be valid for deflated data also.
548 : */
549 1 : log_error(LOG_LEVEL_ERROR,
550 : "Insufficient data to start decompression. Bytes in buffer: %ld",
551 1 : csp->iob->eod - csp->iob->cur);
552 1 : return JB_ERR_COMPRESS;
553 : }
554 :
555 : #ifdef FEATURE_BROTLI
556 355 : if (csp->content_type & CT_BROTLI)
557 : {
558 19 : return decompress_iob_with_brotli(csp);
559 : }
560 : #endif
561 :
562 336 : if (csp->content_type & CT_GZIP)
563 : {
564 : /*
565 : * Our task is slightly complicated by the facts that data
566 : * compressed by gzip does not include a zlib header, and
567 : * that there is no easily accessible interface in zlib to
568 : * handle a gzip header. We strip off the gzip header by
569 : * hand, and later inform zlib not to expect a header.
570 : */
571 :
572 : /*
573 : * Strip off the gzip header. Please see RFC 1952 for more
574 : * explanation of the appropriate fields.
575 : */
576 334 : if (((*cur++ & 0xff) != GZIP_IDENTIFIER_1)
577 323 : || ((*cur++ & 0xff) != GZIP_IDENTIFIER_2)
578 313 : || (*cur++ != Z_DEFLATED))
579 : {
580 39 : log_error(LOG_LEVEL_ERROR, "Invalid gzip header when decompressing");
581 39 : return JB_ERR_COMPRESS;
582 : }
583 : else
584 : {
585 295 : int flags = *cur++;
586 295 : if (flags & GZIP_FLAG_RESERVED_BITS)
587 : {
588 : /* The gzip header has reserved bits set; bail out. */
589 6 : log_error(LOG_LEVEL_ERROR, "Invalid gzip header flags when decompressing");
590 6 : return JB_ERR_COMPRESS;
591 : }
592 :
593 : /*
594 : * Skip mtime (4 bytes), extra flags (1 byte)
595 : * and OS type (1 byte).
596 : */
597 289 : cur += 6;
598 :
599 : /* Skip extra fields if necessary. */
600 289 : if (flags & GZIP_FLAG_EXTRA_FIELDS)
601 : {
602 : /*
603 : * Skip a given number of bytes, specified
604 : * as a 16-bit little-endian value.
605 : *
606 : * XXX: this code is untested and should probably be removed.
607 : */
608 : int skip_bytes;
609 :
610 4 : if (cur + 2 >= csp->iob->eod)
611 : {
612 1 : log_error(LOG_LEVEL_ERROR,
613 : "gzip extra field flag set but insufficient data available.");
614 1 : return JB_ERR_COMPRESS;
615 : }
616 :
617 3 : skip_bytes = *cur++;
618 3 : skip_bytes += (unsigned char)*cur++ << 8;
619 : /*
620 : * The number of bytes to skip should be positive
621 : * and we'd like to stay in the buffer.
622 : */
623 3 : if ((skip_bytes < 0) || (skip_bytes >= (csp->iob->eod - cur)))
624 : {
625 2 : log_error(LOG_LEVEL_ERROR,
626 : "Unreasonable amount of bytes to skip (%d). Stopping decompression",
627 : skip_bytes);
628 2 : return JB_ERR_COMPRESS;
629 : }
630 1 : log_error(LOG_LEVEL_INFO,
631 : "Skipping %d bytes for gzip compression. Does this sound right?",
632 : skip_bytes);
633 1 : cur += skip_bytes;
634 : }
635 :
636 : /* Skip the filename if necessary. */
637 286 : if (flags & GZIP_FLAG_FILE_NAME)
638 : {
639 : /* A null-terminated string is supposed to follow. */
640 7370 : while (*cur++ && (cur < csp->iob->eod));
641 : }
642 :
643 : /* Skip the comment if necessary. */
644 286 : if (flags & GZIP_FLAG_COMMENT)
645 : {
646 : /* A null-terminated string is supposed to follow. */
647 37861 : while (*cur++ && (cur < csp->iob->eod));
648 : }
649 :
650 : /* Skip the CRC if necessary. */
651 286 : if (flags & GZIP_FLAG_CHECKSUM)
652 : {
653 2 : cur += 2;
654 : }
655 :
656 286 : if (cur >= csp->iob->eod)
657 : {
658 : /*
659 : * If the current position pointer reached or passed
660 : * the buffer end, we were obviously tricked to skip
661 : * too much.
662 : */
663 104 : log_error(LOG_LEVEL_ERROR,
664 : "Malformed gzip header detected. Aborting decompression.");
665 104 : return JB_ERR_COMPRESS;
666 : }
667 : }
668 : }
669 2 : else if (csp->content_type & CT_DEFLATE)
670 : {
671 : /*
672 : * In theory (that is, according to RFC 1950), deflate-compressed
673 : * data should begin with a two-byte zlib header and have an
674 : * adler32 checksum at the end. It seems that in practice only
675 : * the raw compressed data is sent. Note that this means that
676 : * we are not RFC 1950-compliant here, but the advantage is that
677 : * this actually works. :)
678 : *
679 : * We add a dummy null byte to tell zlib where the data ends,
680 : * and later inform it not to expect a header.
681 : *
682 : * Fortunately, add_to_iob() has thoughtfully null-terminated
683 : * the buffer; we can just increment the end pointer to include
684 : * the dummy byte.
685 : */
686 2 : csp->iob->eod++;
687 : }
688 : else
689 : {
690 0 : log_error(LOG_LEVEL_ERROR,
691 : "Unable to determine compression format for decompression");
692 0 : return JB_ERR_COMPRESS;
693 : }
694 :
695 : /* Set up the fields required by zlib. */
696 184 : zstr.next_in = (Bytef *)cur;
697 184 : zstr.avail_in = (unsigned int)(csp->iob->eod - cur);
698 184 : zstr.zalloc = Z_NULL;
699 184 : zstr.zfree = Z_NULL;
700 184 : zstr.opaque = Z_NULL;
701 :
702 : /*
703 : * Passing -MAX_WBITS to inflateInit2 tells the library
704 : * that there is no zlib header.
705 : */
706 184 : if (inflateInit2(&zstr, -MAX_WBITS) != Z_OK)
707 : {
708 0 : log_error(LOG_LEVEL_ERROR, "Error initializing decompression");
709 0 : return JB_ERR_COMPRESS;
710 : }
711 :
712 : /*
713 : * Next, we allocate new storage for the inflated data.
714 : * We don't modify the existing iob yet, so in case there
715 : * is error in decompression we can recover gracefully.
716 : */
717 184 : buf = zalloc(bufsize);
718 184 : if (NULL == buf)
719 : {
720 0 : log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
721 0 : return JB_ERR_MEMORY;
722 : }
723 :
724 184 : assert(bufsize >= skip_size);
725 184 : memcpy(buf, csp->iob->buf, skip_size);
726 184 : zstr.avail_out = (uInt)(bufsize - skip_size);
727 184 : zstr.next_out = (Bytef *)buf + skip_size;
728 :
729 : /* Try to decompress the whole stream in one shot. */
730 266 : while (Z_BUF_ERROR == (status = inflate(&zstr, Z_FINISH)))
731 : {
732 : /* We need to allocate more memory for the output buffer. */
733 :
734 : char *tmpbuf; /* used for realloc'ing the buffer */
735 177 : size_t oldbufsize = bufsize; /* keep track of the old bufsize */
736 :
737 177 : if (0 == zstr.avail_in)
738 : {
739 : /*
740 : * If zlib wants more data then there's a problem, because
741 : * the complete compressed file should have been buffered.
742 : */
743 95 : log_error(LOG_LEVEL_ERROR,
744 : "Unexpected end of compressed iob. Using what we got so far.");
745 95 : break;
746 : }
747 :
748 : /*
749 : * If we reached the buffer limit and still didn't have enough
750 : * memory, just give up. Due to the ceiling enforced by the next
751 : * if block we could actually check for equality here, but as it
752 : * can be easily mistaken for a bug we don't.
753 : */
754 82 : if (bufsize >= csp->config->buffer_limit)
755 : {
756 0 : log_error(LOG_LEVEL_ERROR, "Buffer limit reached while decompressing iob");
757 0 : freez(buf);
758 0 : inflateEnd(&zstr);
759 0 : return JB_ERR_MEMORY;
760 : }
761 :
762 : /* Try doubling the buffer size each time. */
763 82 : bufsize *= 2;
764 :
765 : /* Don't exceed the buffer limit. */
766 82 : if (bufsize > csp->config->buffer_limit)
767 : {
768 0 : bufsize = csp->config->buffer_limit;
769 : }
770 :
771 : /* Try to allocate the new buffer. */
772 82 : tmpbuf = realloc(buf, bufsize);
773 82 : if (NULL == tmpbuf)
774 : {
775 0 : log_error(LOG_LEVEL_ERROR, "Out of memory decompressing iob");
776 0 : freez(buf);
777 0 : inflateEnd(&zstr);
778 0 : return JB_ERR_MEMORY;
779 : }
780 : else
781 : {
782 82 : char *oldnext_out = (char *)zstr.next_out;
783 :
784 : /*
785 : * Update the fields for inflate() to use the new
786 : * buffer, which may be in a location different from
787 : * the old one.
788 : */
789 82 : zstr.avail_out += (uInt)(bufsize - oldbufsize);
790 82 : zstr.next_out = (Bytef *)tmpbuf + bufsize - zstr.avail_out;
791 :
792 : /*
793 : * Compare with an uglier method of calculating these values
794 : * that doesn't require the extra oldbufsize variable.
795 : */
796 82 : assert(zstr.avail_out == tmpbuf + bufsize - (char *)zstr.next_out);
797 82 : assert((char *)zstr.next_out == tmpbuf + ((char *)oldnext_out - buf));
798 :
799 82 : buf = tmpbuf;
800 : }
801 : }
802 :
803 184 : if (Z_STREAM_ERROR == inflateEnd(&zstr))
804 : {
805 0 : log_error(LOG_LEVEL_ERROR,
806 : "Inconsistent stream state after decompression: %s", zstr.msg);
807 : /*
808 : * XXX: Intentionally no return.
809 : *
810 : * According to zlib.h, Z_STREAM_ERROR is returned
811 : * "if the stream state was inconsistent".
812 : *
813 : * I assume in this case inflate()'s status
814 : * would also be something different than Z_STREAM_END
815 : * so this check should be redundant, but lets see.
816 : */
817 : }
818 :
819 184 : if ((status != Z_STREAM_END) && (0 != zstr.avail_in))
820 : {
821 : /*
822 : * We failed to decompress the stream and it's
823 : * not simply because of missing data.
824 : */
825 59 : log_error(LOG_LEVEL_ERROR,
826 : "Unexpected error while decompressing to the buffer (iob): %s",
827 : zstr.msg);
828 59 : freez(buf);
829 59 : return JB_ERR_COMPRESS;
830 : }
831 :
832 : /*
833 : * Finally, we can actually update the iob, since the
834 : * decompression was successful. First, free the old
835 : * buffer.
836 : */
837 125 : freez(csp->iob->buf);
838 :
839 : /* Now, update the iob to use the new buffer. */
840 125 : csp->iob->buf = buf;
841 125 : csp->iob->cur = csp->iob->buf + skip_size;
842 125 : csp->iob->eod = (char *)zstr.next_out;
843 125 : csp->iob->size = bufsize;
844 :
845 : /*
846 : * Make sure the new uncompressed iob obeys some minimal
847 : * consistency conditions.
848 : */
849 125 : if ((csp->iob->buf <= csp->iob->cur)
850 125 : && (csp->iob->cur <= csp->iob->eod)
851 125 : && (csp->iob->eod <= csp->iob->buf + csp->iob->size))
852 125 : {
853 125 : const size_t new_size = (size_t)(csp->iob->eod - csp->iob->cur);
854 125 : if (new_size > (size_t)0)
855 : {
856 102 : log_error(LOG_LEVEL_RE_FILTER,
857 : "Decompression successful. Old size: %lu, new size: %lu.",
858 : old_size, new_size);
859 : }
860 : else
861 : {
862 : /* zlib thinks this is OK, so let's do the same. */
863 23 : log_error(LOG_LEVEL_RE_FILTER,
864 : "Decompression didn't result in any content.");
865 : }
866 : }
867 : else
868 : {
869 : /* It seems that zlib did something weird. */
870 0 : log_error(LOG_LEVEL_ERROR, "Inconsistent buffer after decompression");
871 0 : return JB_ERR_COMPRESS;
872 : }
873 :
874 125 : return JB_ERR_OK;
875 :
876 : }
877 : #endif /* defined(FEATURE_ZLIB) */
878 :
879 :
880 : /*********************************************************************
881 : *
882 : * Function : normalize_lws
883 : *
884 : * Description : Reduces unquoted linear whitespace in headers to
885 : * a single space in accordance with RFC 7230 3.2.4.
886 : * This simplifies parsing and filtering later on.
887 : *
888 : * Parameters :
889 : * 1 : header = A header with linear whitespace to reduce.
890 : *
891 : * Returns : N/A
892 : *
893 : *********************************************************************/
894 445505 : static void normalize_lws(char *header)
895 : {
896 445505 : char *p = header;
897 :
898 19015934 : while (*p != '\0')
899 : {
900 18570429 : if (privoxy_isspace(*p) && privoxy_isspace(*(p+1)))
901 : {
902 5468 : char *q = p+1;
903 :
904 24954 : while (privoxy_isspace(*q))
905 : {
906 19486 : q++;
907 : }
908 5468 : log_error(LOG_LEVEL_HEADER, "Reducing whitespace in '%s'", header);
909 5468 : string_move(p+1, q);
910 : }
911 :
912 18570429 : if (*p == '\t')
913 : {
914 3603 : log_error(LOG_LEVEL_HEADER,
915 : "Converting tab to space in '%s'", header);
916 3603 : *p = ' ';
917 : }
918 18566826 : else if (*p == '"')
919 : {
920 12641 : char *end_of_token = strstr(p+1, "\"");
921 :
922 12641 : if (NULL != end_of_token)
923 : {
924 : /* Don't mess with quoted text. */
925 7863 : p = end_of_token;
926 : }
927 : else
928 : {
929 4778 : log_error(LOG_LEVEL_HEADER,
930 : "Ignoring single quote in '%s'", header);
931 : }
932 : }
933 18570429 : p++;
934 : }
935 :
936 445505 : p = strchr(header, ':');
937 445505 : if ((p != NULL) && (p != header) && privoxy_isspace(*(p-1)))
938 : {
939 : /*
940 : * There's still space before the colon.
941 : * We don't want it.
942 : */
943 178 : string_move(p-1, p);
944 : }
945 445505 : }
946 :
947 :
948 : /*********************************************************************
949 : *
950 : * Function : get_header
951 : *
952 : * Description : This (odd) routine will parse the csp->iob
953 : * to get the next complete header.
954 : *
955 : * Parameters :
956 : * 1 : iob = The I/O buffer to parse, usually csp->iob.
957 : *
958 : * Returns : Any one of the following:
959 : *
960 : * 1) a pointer to a dynamically allocated string that contains a header line
961 : * 2) NULL indicating that the end of the header was reached
962 : * 3) "" indicating that the end of the iob was reached before finding
963 : * a complete header line.
964 : *
965 : *********************************************************************/
966 501306 : char *get_header(struct iob *iob)
967 : {
968 : char *header;
969 :
970 501306 : header = get_header_line(iob);
971 :
972 501306 : if ((header == NULL) || (*header == '\0'))
973 : {
974 : /*
975 : * No complete header read yet, tell the client.
976 : */
977 55801 : return header;
978 : }
979 :
980 446359 : while ((iob->cur[0] == ' ') || (iob->cur[0] == '\t'))
981 : {
982 : /*
983 : * Header spans multiple lines, append the next one.
984 : */
985 : char *continued_header;
986 :
987 1001 : continued_header = get_header_line(iob);
988 1001 : if ((continued_header == NULL) || (*continued_header == '\0'))
989 : {
990 : /*
991 : * No complete header read yet, return what we got.
992 : * XXX: Should "unread" header instead.
993 : */
994 147 : log_error(LOG_LEVEL_INFO,
995 : "Failed to read a multi-line header properly: '%s'",
996 : header);
997 147 : break;
998 : }
999 :
1000 854 : if (JB_ERR_OK != string_join(&header, continued_header))
1001 : {
1002 0 : log_error(LOG_LEVEL_FATAL,
1003 : "Out of memory while appending multiple headers.");
1004 : }
1005 : else
1006 : {
1007 : /* XXX: remove before next stable release. */
1008 854 : log_error(LOG_LEVEL_HEADER,
1009 : "Merged multiple header lines to: '%s'",
1010 : header);
1011 : }
1012 : }
1013 :
1014 445505 : normalize_lws(header);
1015 :
1016 445505 : return header;
1017 :
1018 : }
1019 :
1020 :
1021 : /*********************************************************************
1022 : *
1023 : * Function : get_header_line
1024 : *
1025 : * Description : This (odd) routine will parse the csp->iob
1026 : * to get the next header line.
1027 : *
1028 : * Parameters :
1029 : * 1 : iob = The I/O buffer to parse, usually csp->iob.
1030 : *
1031 : * Returns : Any one of the following:
1032 : *
1033 : * 1) a pointer to a dynamically allocated string that contains a header line
1034 : * 2) NULL indicating that the end of the header was reached
1035 : * 3) "" indicating that the end of the iob was reached before finding
1036 : * a complete header line.
1037 : *
1038 : *********************************************************************/
1039 502307 : static char *get_header_line(struct iob *iob)
1040 : {
1041 : char *p, *q, *ret;
1042 502307 : if ((iob->cur == NULL)
1043 502307 : || ((p = strchr(iob->cur, '\n')) == NULL))
1044 : {
1045 16208 : return(""); /* couldn't find a complete header */
1046 : }
1047 :
1048 486099 : *p = '\0';
1049 :
1050 486099 : ret = strdup(iob->cur);
1051 486099 : if (ret == NULL)
1052 : {
1053 : /* FIXME No way to handle error properly */
1054 0 : log_error(LOG_LEVEL_FATAL, "Out of memory in get_header_line()");
1055 : }
1056 486099 : assert(ret != NULL);
1057 :
1058 486099 : iob->cur = p+1;
1059 :
1060 486099 : if ((q = strchr(ret, '\r')) != NULL) *q = '\0';
1061 :
1062 : /* is this a blank line (i.e. the end of the header) ? */
1063 486099 : if (*ret == '\0')
1064 : {
1065 39740 : freez(ret);
1066 39740 : return NULL;
1067 : }
1068 :
1069 446359 : return ret;
1070 :
1071 : }
1072 :
1073 :
1074 : /*********************************************************************
1075 : *
1076 : * Function : get_header_value
1077 : *
1078 : * Description : Get the value of a given header from a chained list
1079 : * of header lines or return NULL if no such header is
1080 : * present in the list.
1081 : *
1082 : * Parameters :
1083 : * 1 : header_list = pointer to list
1084 : * 2 : header_name = string with name of header to look for.
1085 : * Trailing colon required, capitalization
1086 : * doesn't matter.
1087 : *
1088 : * Returns : NULL if not found, else value of header
1089 : *
1090 : *********************************************************************/
1091 80960 : char *get_header_value(const struct list *header_list, const char *header_name)
1092 : {
1093 : struct list_entry *cur_entry;
1094 80960 : char *ret = NULL;
1095 80960 : size_t length = 0;
1096 :
1097 80960 : assert(header_list);
1098 80960 : assert(header_name);
1099 80960 : length = strlen(header_name);
1100 :
1101 672793 : for (cur_entry = header_list->first; cur_entry ; cur_entry = cur_entry->next)
1102 : {
1103 612490 : if (cur_entry->str)
1104 : {
1105 612490 : if (!strncmpic(cur_entry->str, header_name, length))
1106 : {
1107 : /*
1108 : * Found: return pointer to start of value
1109 : */
1110 20657 : ret = cur_entry->str + length;
1111 37804 : while (*ret && privoxy_isspace(*ret)) ret++;
1112 20657 : return ret;
1113 : }
1114 : }
1115 : }
1116 :
1117 : /*
1118 : * Not found
1119 : */
1120 60303 : return NULL;
1121 :
1122 : }
1123 :
1124 :
1125 : /*********************************************************************
1126 : *
1127 : * Function : scan_headers
1128 : *
1129 : * Description : Scans headers, applies tags and updates action bits.
1130 : *
1131 : * Parameters :
1132 : * 1 : csp = Current client state (buffers, headers, etc...)
1133 : *
1134 : * Returns : JB_ERR_OK
1135 : *
1136 : *********************************************************************/
1137 39281 : static jb_err scan_headers(struct client_state *csp)
1138 : {
1139 : struct list_entry *h; /* Header */
1140 39281 : jb_err err = JB_ERR_OK;
1141 :
1142 449472 : for (h = csp->headers->first; (err == JB_ERR_OK) && (h != NULL) ; h = h->next)
1143 : {
1144 : /* Header crunch()ed in previous run? -> ignore */
1145 410191 : if (h->str == NULL) continue;
1146 410191 : log_error(LOG_LEVEL_HEADER, "scan: %s", h->str);
1147 410191 : err = header_tagger(csp, h->str);
1148 : }
1149 :
1150 39281 : return err;
1151 : }
1152 :
1153 :
1154 : /*********************************************************************
1155 : *
1156 : * Function : enforce_header_order
1157 : *
1158 : * Description : Enforces a given header order.
1159 : *
1160 : * Parameters :
1161 : * 1 : headers = List of headers to order.
1162 : * 2 : ordered_headers = List of ordered header names.
1163 : *
1164 : * Returns : N/A
1165 : *
1166 : *********************************************************************/
1167 33270 : static void enforce_header_order(struct list *headers, const struct list *ordered_headers)
1168 : {
1169 : struct list_entry *sorted_header;
1170 : struct list new_headers[1];
1171 : struct list_entry *header;
1172 :
1173 33270 : init_list(new_headers);
1174 :
1175 : /* The request line is always the first "header" */
1176 :
1177 33270 : assert(NULL != headers->first->str);
1178 33270 : enlist(new_headers, headers->first->str);
1179 33270 : freez(headers->first->str)
1180 :
1181 : /* Enlist the specified headers in the given order */
1182 :
1183 299430 : for (sorted_header = ordered_headers->first; sorted_header != NULL;
1184 266160 : sorted_header = sorted_header->next)
1185 : {
1186 266160 : const size_t sorted_header_length = strlen(sorted_header->str);
1187 3106912 : for (header = headers->first; header != NULL; header = header->next)
1188 : {
1189 : /* Header enlisted in previous run? -> ignore */
1190 2840752 : if (header->str == NULL) continue;
1191 :
1192 1894193 : if (0 == strncmpic(sorted_header->str, header->str, sorted_header_length)
1193 125991 : && (header->str[sorted_header_length] == ':'))
1194 : {
1195 106647 : log_error(LOG_LEVEL_HEADER, "Enlisting sorted header %s", header->str);
1196 106647 : if (JB_ERR_OK != enlist(new_headers, header->str))
1197 : {
1198 0 : log_error(LOG_LEVEL_HEADER, "Failed to enlist %s", header->str);
1199 : }
1200 106647 : freez(header->str);
1201 : }
1202 : }
1203 : }
1204 :
1205 : /* Enlist the rest of the headers behind the ordered ones */
1206 388364 : for (header = headers->first; header != NULL; header = header->next)
1207 : {
1208 : /* Header enlisted in previous run? -> ignore */
1209 355094 : if (header->str == NULL) continue;
1210 :
1211 205975 : log_error(LOG_LEVEL_HEADER,
1212 : "Enlisting left-over header %s", header->str);
1213 205975 : if (JB_ERR_OK != enlist(new_headers, header->str))
1214 : {
1215 0 : log_error(LOG_LEVEL_HEADER, "Failed to enlist %s", header->str);
1216 : }
1217 205975 : freez(header->str);
1218 : }
1219 :
1220 33270 : list_remove_all(headers);
1221 33270 : headers->first = new_headers->first;
1222 33270 : headers->last = new_headers->last;
1223 :
1224 66540 : return;
1225 : }
1226 :
1227 :
1228 : /*********************************************************************
1229 : *
1230 : * Function : sed
1231 : *
1232 : * Description : add, delete or modify lines in the HTTP header streams.
1233 : * On entry, it receives a linked list of headers space
1234 : * that was allocated dynamically (both the list nodes
1235 : * and the header contents).
1236 : *
1237 : * As a side effect it frees the space used by the original
1238 : * header lines.
1239 : *
1240 : * Parameters :
1241 : * 1 : csp = Current client state (buffers, headers, etc...)
1242 : * 2 : filter_server_headers = Boolean to switch between
1243 : * server and header filtering.
1244 : *
1245 : * Returns : JB_ERR_OK in case off success, or
1246 : * JB_ERR_MEMORY on some out-of-memory errors, or
1247 : * JB_ERR_PARSE in case of fatal parse errors.
1248 : *
1249 : *********************************************************************/
1250 39281 : jb_err sed(struct client_state *csp, int filter_server_headers)
1251 : {
1252 : /* XXX: use more descriptive names. */
1253 : struct list_entry *p;
1254 : const struct parsers *v;
1255 : const add_header_func_ptr *f;
1256 39281 : jb_err err = JB_ERR_OK;
1257 :
1258 39281 : scan_headers(csp);
1259 :
1260 39281 : if (filter_server_headers)
1261 : {
1262 6009 : v = server_patterns;
1263 6009 : f = add_server_headers;
1264 6009 : check_negative_tag_patterns(csp, PATTERN_SPEC_NO_RESPONSE_TAG_PATTERN);
1265 : }
1266 : else
1267 : {
1268 33272 : v = client_patterns;
1269 33272 : f = add_client_headers;
1270 33272 : check_negative_tag_patterns(csp, PATTERN_SPEC_NO_REQUEST_TAG_PATTERN);
1271 : }
1272 :
1273 960841 : while (v->str != NULL)
1274 : {
1275 10290297 : for (p = csp->headers->first; p != NULL; p = p->next)
1276 : {
1277 : /* Header crunch()ed in previous run? -> ignore */
1278 9368737 : if (p->str == NULL) continue;
1279 :
1280 : /* Does the current parser handle this header? */
1281 9244951 : if ((strncmpic(p->str, v->str, v->len) == 0) ||
1282 8303326 : (v->len == CHECK_EVERY_HEADER_REMAINING))
1283 : {
1284 941625 : err = v->parser(csp, &(p->str));
1285 941625 : if (err != JB_ERR_OK)
1286 : {
1287 25 : return err;
1288 : }
1289 : }
1290 : }
1291 921560 : v++;
1292 : }
1293 :
1294 : /* place additional headers on the csp->headers list */
1295 184303 : while ((err == JB_ERR_OK) && (*f))
1296 : {
1297 145047 : err = (*f)(csp);
1298 145047 : f++;
1299 : }
1300 :
1301 72528 : if (!filter_server_headers &&
1302 66544 : !list_is_empty(csp->config->ordered_client_headers) &&
1303 33272 : csp->headers->first->str != NULL)
1304 : {
1305 33270 : enforce_header_order(csp->headers, csp->config->ordered_client_headers);
1306 : }
1307 :
1308 39256 : return err;
1309 : }
1310 :
1311 :
1312 : #ifdef FEATURE_HTTPS_INSPECTION
1313 : /*********************************************************************
1314 : *
1315 : * Function : sed_https
1316 : *
1317 : * Description : add, delete or modify lines in the HTTPS client
1318 : * header streams. Wrapper around sed().
1319 : *
1320 : * Parameters :
1321 : * 1 : csp = Current client state (buffers, headers, etc...)
1322 : *
1323 : * Returns : JB_ERR_OK in case off success, or
1324 : * JB_ERR_MEMORY on some out-of-memory errors, or
1325 : * JB_ERR_PARSE in case of fatal parse errors.
1326 : *
1327 : *********************************************************************/
1328 2129 : jb_err sed_https(struct client_state *csp)
1329 : {
1330 : jb_err err;
1331 : struct list headers;
1332 :
1333 : /*
1334 : * Temporarily replace csp->headers with csp->https_headers
1335 : * to trick sed() into filtering the https headers.
1336 : */
1337 2129 : headers.first = csp->headers->first;
1338 2129 : headers.last = csp->headers->last;
1339 2129 : csp->headers->first = csp->https_headers->first;
1340 2129 : csp->headers->last = csp->https_headers->last;
1341 :
1342 : /*
1343 : * Start with fresh tags. Already existing tags may
1344 : * be set again. This is necessary to overrule
1345 : * URL-based patterns.
1346 : */
1347 2129 : destroy_list(csp->tags);
1348 :
1349 : /*
1350 : * We want client header filters and taggers
1351 : * so temporarily remove the flag.
1352 : */
1353 2129 : csp->flags &= ~CSP_FLAG_CLIENT_HEADER_PARSING_DONE;
1354 2129 : err = sed(csp, FILTER_CLIENT_HEADERS);
1355 2129 : csp->flags |= CSP_FLAG_CLIENT_HEADER_PARSING_DONE;
1356 :
1357 : /*
1358 : * Update the https headers list which may have
1359 : * been modified due to header additions or header
1360 : * reordering.
1361 : */
1362 2129 : csp->https_headers->first = csp->headers->first;
1363 2129 : csp->https_headers->last = csp->headers->last;
1364 :
1365 2129 : csp->headers->first = headers.first;
1366 2129 : csp->headers->last = headers.last;
1367 :
1368 2129 : return err;
1369 : }
1370 : #endif /* def FEATURE_HTTPS_INSPECTION */
1371 :
1372 :
1373 : /*********************************************************************
1374 : *
1375 : * Function : update_server_headers
1376 : *
1377 : * Description : Updates server headers after the body has been modified.
1378 : *
1379 : * Parameters :
1380 : * 1 : csp = Current client state (buffers, headers, etc...)
1381 : *
1382 : * Returns : JB_ERR_OK in case off success, or
1383 : * JB_ERR_MEMORY on out-of-memory error.
1384 : *
1385 : *********************************************************************/
1386 4492 : jb_err update_server_headers(struct client_state *csp)
1387 : {
1388 4492 : jb_err err = JB_ERR_OK;
1389 :
1390 : static const struct parsers server_patterns_light[] = {
1391 : { "Content-Length:", 15, server_adjust_content_length },
1392 : { "Transfer-Encoding:", 18, server_transfer_coding },
1393 : #ifdef FEATURE_ZLIB
1394 : { "Content-Encoding:", 17, server_adjust_content_encoding },
1395 : #endif /* def FEATURE_ZLIB */
1396 : { NULL, 0, NULL }
1397 : };
1398 :
1399 4492 : if (strncmpic(csp->http->cmd, "HEAD", 4))
1400 : {
1401 : const struct parsers *v;
1402 : struct list_entry *p;
1403 :
1404 17240 : for (v = server_patterns_light; (err == JB_ERR_OK) && (v->str != NULL); v++)
1405 : {
1406 149922 : for (p = csp->headers->first; (err == JB_ERR_OK) && (p != NULL); p = p->next)
1407 : {
1408 : /* Header crunch()ed in previous run? -> ignore */
1409 136992 : if (p->str == NULL) continue;
1410 :
1411 : /* Does the current parser handle this header? */
1412 129848 : if (strncmpic(p->str, v->str, v->len) == 0)
1413 : {
1414 3863 : err = v->parser(csp, (char **)&(p->str));
1415 : }
1416 : }
1417 : }
1418 : }
1419 :
1420 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1421 4492 : if ((JB_ERR_OK == err)
1422 4492 : && (csp->flags & CSP_FLAG_MODIFIED)
1423 1311 : && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
1424 1295 : && !(csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET))
1425 : {
1426 : char header[50];
1427 :
1428 1135 : create_content_length_header(csp->content_length, header, sizeof(header));
1429 1135 : err = enlist(csp->headers, header);
1430 1135 : if (JB_ERR_OK == err)
1431 : {
1432 1135 : log_error(LOG_LEVEL_HEADER,
1433 : "Content modified with no Content-Length header set. "
1434 : "Created: %s.", header);
1435 1135 : csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1436 : }
1437 : }
1438 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1439 :
1440 : #ifdef FEATURE_COMPRESSION
1441 4492 : if ((JB_ERR_OK == err)
1442 4492 : && (csp->flags & CSP_FLAG_BUFFERED_CONTENT_DEFLATED))
1443 : {
1444 12 : err = enlist_unique_header(csp->headers, "Content-Encoding", "deflate");
1445 12 : if (JB_ERR_OK == err)
1446 : {
1447 12 : log_error(LOG_LEVEL_HEADER, "Added header: Content-Encoding: deflate");
1448 : }
1449 : }
1450 : #endif
1451 :
1452 4492 : return err;
1453 : }
1454 :
1455 :
1456 : /*********************************************************************
1457 : *
1458 : * Function : header_tagger
1459 : *
1460 : * Description : Executes all text substitutions from applying
1461 : * tag actions and saves the result as tag.
1462 : *
1463 : * XXX: Shares enough code with filter_header() and
1464 : * pcrs_filter_response() to warrant some helper functions.
1465 : *
1466 : * Parameters :
1467 : * 1 : csp = Current client state (buffers, headers, etc...)
1468 : * 2 : header = Header that is used as tagger input
1469 : *
1470 : * Returns : JB_ERR_OK on success and always succeeds
1471 : *
1472 : *********************************************************************/
1473 410191 : static jb_err header_tagger(struct client_state *csp, char *header)
1474 : {
1475 : enum filter_type wanted_filter_type;
1476 : int multi_action_index;
1477 : pcrs_job *job;
1478 :
1479 : struct re_filterfile_spec *b;
1480 : struct list_entry *tag_name;
1481 :
1482 410191 : const size_t header_length = strlen(header);
1483 :
1484 410191 : if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1485 : {
1486 86859 : wanted_filter_type = FT_SERVER_HEADER_TAGGER;
1487 86859 : multi_action_index = ACTION_MULTI_SERVER_HEADER_TAGGER;
1488 : }
1489 : else
1490 : {
1491 323332 : wanted_filter_type = FT_CLIENT_HEADER_TAGGER;
1492 323332 : multi_action_index = ACTION_MULTI_CLIENT_HEADER_TAGGER;
1493 : }
1494 :
1495 410191 : if (list_is_empty(csp->action->multi[multi_action_index])
1496 392042 : || filters_available(csp) == FALSE)
1497 : {
1498 : /* Return early if no taggers apply or if none are available. */
1499 18149 : return JB_ERR_OK;
1500 : }
1501 :
1502 : /* Execute all applying taggers */
1503 784084 : for (tag_name = csp->action->multi[multi_action_index]->first;
1504 392042 : NULL != tag_name; tag_name = tag_name->next)
1505 : {
1506 392042 : char *modified_tag = NULL;
1507 392042 : char *tag = header;
1508 392042 : size_t size = header_length;
1509 : pcrs_job *joblist;
1510 :
1511 392042 : b = get_filter(csp, tag_name->str, wanted_filter_type);
1512 392042 : if (b == NULL)
1513 : {
1514 67 : continue;
1515 : }
1516 :
1517 392042 : joblist = b->joblist;
1518 :
1519 392042 : if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1520 :
1521 392042 : if (NULL == joblist)
1522 : {
1523 0 : log_error(LOG_LEVEL_TAGGING,
1524 : "Tagger %s has empty joblist. Nothing to do.", b->name);
1525 0 : continue;
1526 : }
1527 :
1528 : /* execute their pcrs_joblist on the header. */
1529 784084 : for (job = joblist; NULL != job; job = job->next)
1530 : {
1531 392042 : const int hits = pcrs_execute(job, tag, size, &modified_tag, &size);
1532 :
1533 392042 : if (0 < hits)
1534 : {
1535 : /* Success, continue with the modified version. */
1536 11027 : if (tag != header)
1537 : {
1538 0 : freez(tag);
1539 : }
1540 11027 : tag = modified_tag;
1541 : }
1542 : else
1543 : {
1544 : /* Tagger doesn't match */
1545 381015 : if (0 > hits)
1546 : {
1547 : /* Regex failure, log it but continue anyway. */
1548 0 : assert(NULL != header);
1549 0 : log_error(LOG_LEVEL_ERROR,
1550 : "Problems with tagger \'%s\' and header \'%s\': %s",
1551 : b->name, header, pcrs_strerror(hits));
1552 : }
1553 381015 : freez(modified_tag);
1554 : }
1555 : }
1556 :
1557 392042 : if (b->dynamic) pcrs_free_joblist(joblist);
1558 :
1559 : /* If this tagger matched */
1560 392042 : if (tag != header)
1561 : {
1562 11027 : if (0 == size)
1563 : {
1564 : /*
1565 : * There is no technical limitation which makes
1566 : * it impossible to use empty tags, but I assume
1567 : * no one would do it intentionally.
1568 : */
1569 67 : freez(tag);
1570 67 : log_error(LOG_LEVEL_TAGGING,
1571 : "Tagger \'%s\' created an empty tag. Ignored.", b->name);
1572 67 : continue;
1573 : }
1574 :
1575 10960 : if (list_contains_item(csp->action->multi[ACTION_MULTI_SUPPRESS_TAG], tag))
1576 : {
1577 0 : log_error(LOG_LEVEL_TAGGING,
1578 : "Tagger \'%s\' didn't add tag \'%s\': suppressed",
1579 : b->name, tag);
1580 0 : freez(tag);
1581 0 : continue;
1582 : }
1583 :
1584 10960 : if (!list_contains_item(csp->tags, tag))
1585 : {
1586 10729 : if (JB_ERR_OK != enlist(csp->tags, tag))
1587 : {
1588 0 : log_error(LOG_LEVEL_ERROR,
1589 : "Insufficient memory to add tag \'%s\', "
1590 : "based on tagger \'%s\' and header \'%s\'",
1591 : tag, b->name, header);
1592 : }
1593 : else
1594 : {
1595 : char *action_message;
1596 : /*
1597 : * update the action bits right away, to make
1598 : * tagging based on tags set by earlier taggers
1599 : * of the same kind possible.
1600 : */
1601 10729 : if (update_action_bits_for_tag(csp, tag))
1602 : {
1603 0 : action_message = "Action bits updated accordingly.";
1604 : }
1605 : else
1606 : {
1607 10729 : action_message = "No action bits update necessary.";
1608 : }
1609 :
1610 10729 : log_error(LOG_LEVEL_TAGGING,
1611 : "Tagger \'%s\' added tag \'%s\'. %s",
1612 : b->name, tag, action_message);
1613 : }
1614 : }
1615 : else
1616 : {
1617 : /* XXX: Is this log-worthy? */
1618 231 : log_error(LOG_LEVEL_TAGGING,
1619 : "Tagger \'%s\' didn't add tag \'%s\'. Tag already present",
1620 : b->name, tag);
1621 : }
1622 10960 : freez(tag);
1623 : }
1624 : }
1625 :
1626 392042 : return JB_ERR_OK;
1627 : }
1628 :
1629 : /* here begins the family of parser functions that reformat header lines */
1630 :
1631 : /*********************************************************************
1632 : *
1633 : * Function : filter_header
1634 : *
1635 : * Description : Executes all text substitutions from all applying
1636 : * +(server|client)-header-filter actions on the header.
1637 : * Most of the code was copied from pcrs_filter_response,
1638 : * including the rather short variable names
1639 : *
1640 : * Parameters :
1641 : * 1 : csp = Current client state (buffers, headers, etc...)
1642 : * 2 : header = On input, pointer to header to modify.
1643 : * On output, pointer to the modified header, or NULL
1644 : * to remove the header. This function frees the
1645 : * original string if necessary.
1646 : *
1647 : * Returns : JB_ERR_OK on success and always succeeds
1648 : *
1649 : *********************************************************************/
1650 397650 : static jb_err filter_header(struct client_state *csp, char **header)
1651 : {
1652 397650 : int hits=0;
1653 : int matches;
1654 397650 : size_t size = strlen(*header);
1655 :
1656 397650 : char *newheader = NULL;
1657 : pcrs_job *job;
1658 :
1659 : struct re_filterfile_spec *b;
1660 : struct list_entry *filtername;
1661 :
1662 : enum filter_type wanted_filter_type;
1663 : int multi_action_index;
1664 :
1665 397650 : if (csp->flags & CSP_FLAG_NO_FILTERING)
1666 : {
1667 338 : return JB_ERR_OK;
1668 : }
1669 :
1670 397312 : if (csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
1671 : {
1672 81323 : wanted_filter_type = FT_SERVER_HEADER_FILTER;
1673 81323 : multi_action_index = ACTION_MULTI_SERVER_HEADER_FILTER;
1674 : }
1675 : else
1676 : {
1677 315989 : wanted_filter_type = FT_CLIENT_HEADER_FILTER;
1678 315989 : multi_action_index = ACTION_MULTI_CLIENT_HEADER_FILTER;
1679 : }
1680 :
1681 397312 : if (list_is_empty(csp->action->multi[multi_action_index])
1682 379709 : || filters_available(csp) == FALSE)
1683 : {
1684 : /* Return early if no filters apply or if none are available. */
1685 17603 : return JB_ERR_OK;
1686 : }
1687 :
1688 : /* Execute all applying header filters */
1689 1670407 : for (filtername = csp->action->multi[multi_action_index]->first;
1690 1290698 : filtername != NULL; filtername = filtername->next)
1691 : {
1692 1290698 : int current_hits = 0;
1693 : pcrs_job *joblist;
1694 :
1695 1290698 : b = get_filter(csp, filtername->str, wanted_filter_type);
1696 1290698 : if (b == NULL)
1697 : {
1698 0 : continue;
1699 : }
1700 :
1701 1290698 : joblist = b->joblist;
1702 :
1703 1290698 : if (b->dynamic) joblist = compile_dynamic_pcrs_job_list(csp, b);
1704 :
1705 1290698 : if (NULL == joblist)
1706 : {
1707 0 : log_error(LOG_LEVEL_RE_FILTER,
1708 : "Filter %s has empty joblist. Nothing to do.", b->name);
1709 0 : continue;
1710 : }
1711 :
1712 1290698 : log_error(LOG_LEVEL_RE_FILTER, "filtering \'%s\' (size %lu) with \'%s\' ...",
1713 : *header, size, b->name);
1714 :
1715 : /* Apply all jobs from the joblist */
1716 2581396 : for (job = joblist; NULL != job; job = job->next)
1717 : {
1718 1290698 : matches = pcrs_execute(job, *header, size, &newheader, &size);
1719 1290698 : if (0 < matches)
1720 : {
1721 2515 : current_hits += matches;
1722 2515 : log_error(LOG_LEVEL_HEADER,
1723 : "Transforming \"%s\" to \"%s\"", *header, newheader);
1724 2515 : freez(*header);
1725 2515 : *header = newheader;
1726 : }
1727 1288183 : else if (0 == matches)
1728 : {
1729 : /* Filter doesn't change header */
1730 1288183 : freez(newheader);
1731 : }
1732 : else
1733 : {
1734 : /* RegEx failure */
1735 0 : log_error(LOG_LEVEL_ERROR,
1736 : "Filtering \'%s\' with \'%s\' didn't work out: %s",
1737 : *header, b->name, pcrs_strerror(matches));
1738 0 : if (newheader != NULL)
1739 : {
1740 0 : log_error(LOG_LEVEL_ERROR, "Freeing what's left: %s", newheader);
1741 0 : freez(newheader);
1742 : }
1743 : }
1744 : }
1745 :
1746 1290698 : if (b->dynamic) pcrs_free_joblist(joblist);
1747 :
1748 1290698 : log_error(LOG_LEVEL_RE_FILTER,
1749 : "... produced %d hits (new size %lu).", current_hits, size);
1750 1290698 : hits += current_hits;
1751 : }
1752 :
1753 : /*
1754 : * Additionally checking for hits is important because if
1755 : * the continue hack is triggered, server headers can
1756 : * arrive empty to separate multiple heads from each other.
1757 : */
1758 379709 : if ((0 == size) && hits)
1759 : {
1760 2201 : log_error(LOG_LEVEL_HEADER, "Removing empty header %s", *header);
1761 2201 : freez(*header);
1762 : }
1763 :
1764 379709 : return JB_ERR_OK;
1765 : }
1766 :
1767 :
1768 : /*********************************************************************
1769 : *
1770 : * Function : server_connection
1771 : *
1772 : * Description : Makes sure a proper "Connection:" header is
1773 : * set and signals connection_header_adder to
1774 : * do nothing.
1775 : *
1776 : * Parameters :
1777 : * 1 : csp = Current client state (buffers, headers, etc...)
1778 : * 2 : header = On input, pointer to header to modify.
1779 : * On output, pointer to the modified header, or NULL
1780 : * to remove the header. This function frees the
1781 : * original string if necessary.
1782 : *
1783 : * Returns : JB_ERR_OK on success.
1784 : *
1785 : *********************************************************************/
1786 2722 : static jb_err server_connection(struct client_state *csp, char **header)
1787 : {
1788 2722 : if (!strcmpic(*header, "Connection: keep-alive")
1789 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1790 1400 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
1791 : #endif
1792 : )
1793 : {
1794 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1795 1126 : if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1796 : {
1797 1126 : csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
1798 : }
1799 :
1800 1126 : if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE))
1801 : {
1802 804 : log_error(LOG_LEVEL_HEADER,
1803 : "Keeping the server header '%s' around.", *header);
1804 : }
1805 : else
1806 : #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1807 : {
1808 322 : char *old_header = *header;
1809 :
1810 322 : *header = strdup_or_die("Connection: close");
1811 322 : log_error(LOG_LEVEL_HEADER, "Replaced: \'%s\' with \'%s\'", old_header, *header);
1812 322 : freez(old_header);
1813 : }
1814 : }
1815 :
1816 : /* Signal server_connection_adder() to return early. */
1817 2722 : csp->flags |= CSP_FLAG_SERVER_CONNECTION_HEADER_SET;
1818 :
1819 2722 : return JB_ERR_OK;
1820 : }
1821 :
1822 :
1823 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1824 : /*********************************************************************
1825 : *
1826 : * Function : server_keep_alive
1827 : *
1828 : * Description : Stores the server's keep alive timeout.
1829 : *
1830 : * Parameters :
1831 : * 1 : csp = Current client state (buffers, headers, etc...)
1832 : * 2 : header = On input, pointer to header to modify.
1833 : * On output, pointer to the modified header, or NULL
1834 : * to remove the header. This function frees the
1835 : * original string if necessary.
1836 : *
1837 : * Returns : JB_ERR_OK.
1838 : *
1839 : *********************************************************************/
1840 900 : static jb_err server_keep_alive(struct client_state *csp, char **header)
1841 : {
1842 : unsigned int keep_alive_timeout;
1843 900 : const char *timeout_position = strstr(*header, "timeout=");
1844 :
1845 900 : if ((NULL == timeout_position)
1846 394 : || (1 != sscanf(timeout_position, "timeout=%u", &keep_alive_timeout)))
1847 : {
1848 572 : log_error(LOG_LEVEL_ERROR, "Couldn't parse: %s", *header);
1849 : }
1850 : else
1851 : {
1852 328 : if (keep_alive_timeout < csp->server_connection.keep_alive_timeout)
1853 : {
1854 204 : log_error(LOG_LEVEL_HEADER,
1855 : "Reducing keep-alive timeout from %u to %u.",
1856 : csp->server_connection.keep_alive_timeout, keep_alive_timeout);
1857 204 : csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1858 : }
1859 : else
1860 : {
1861 : /* XXX: Is this log worthy? */
1862 124 : log_error(LOG_LEVEL_HEADER,
1863 : "Server keep-alive timeout is %u. Sticking with %u.",
1864 : keep_alive_timeout, csp->server_connection.keep_alive_timeout);
1865 : }
1866 328 : csp->flags |= CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET;
1867 : }
1868 :
1869 900 : freez(*header);
1870 :
1871 900 : return JB_ERR_OK;
1872 : }
1873 :
1874 :
1875 : /*********************************************************************
1876 : *
1877 : * Function : server_proxy_connection
1878 : *
1879 : * Description : Figures out whether or not we should add a
1880 : * Proxy-Connection header.
1881 : *
1882 : * Parameters :
1883 : * 1 : csp = Current client state (buffers, headers, etc...)
1884 : * 2 : header = On input, pointer to header to modify.
1885 : * On output, pointer to the modified header, or NULL
1886 : * to remove the header. This function frees the
1887 : * original string if necessary.
1888 : *
1889 : * Returns : JB_ERR_OK.
1890 : *
1891 : *********************************************************************/
1892 186 : static jb_err server_proxy_connection(struct client_state *csp, char **header)
1893 : {
1894 186 : csp->flags |= CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET;
1895 186 : return JB_ERR_OK;
1896 : }
1897 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1898 :
1899 :
1900 : /*********************************************************************
1901 : *
1902 : * Function : proxy_authentication
1903 : *
1904 : * Description : Removes headers that are relevant for proxy
1905 : * authentication unless forwarding them has
1906 : * been explicitly requested.
1907 : *
1908 : * Parameters :
1909 : * 1 : csp = Current client state (buffers, headers, etc...)
1910 : * 2 : header = On input, pointer to header to modify.
1911 : * On output, pointer to the modified header, or NULL
1912 : * to remove the header. This function frees the
1913 : * original string if necessary.
1914 : *
1915 : * Returns : JB_ERR_OK.
1916 : *
1917 : *********************************************************************/
1918 78 : static jb_err proxy_authentication(struct client_state *csp, char **header)
1919 : {
1920 78 : if ((csp->config->feature_flags &
1921 : RUNTIME_FEATURE_FORWARD_PROXY_AUTHENTICATION_HEADERS) == 0) {
1922 0 : log_error(LOG_LEVEL_HEADER,
1923 : "Forwarding proxy authentication headers is disabled. Crunching: %s", *header);
1924 0 : freez(*header);
1925 : }
1926 78 : return JB_ERR_OK;
1927 : }
1928 :
1929 :
1930 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1931 : /*********************************************************************
1932 : *
1933 : * Function : client_keep_alive
1934 : *
1935 : * Description : Stores the client's keep alive timeout.
1936 : *
1937 : * Parameters :
1938 : * 1 : csp = Current client state (buffers, headers, etc...)
1939 : * 2 : header = On input, pointer to header to modify.
1940 : * On output, pointer to the modified header, or NULL
1941 : * to remove the header. This function frees the
1942 : * original string if necessary.
1943 : *
1944 : * Returns : JB_ERR_OK.
1945 : *
1946 : *********************************************************************/
1947 1876 : static jb_err client_keep_alive(struct client_state *csp, char **header)
1948 : {
1949 : unsigned int keep_alive_timeout;
1950 : char *timeout_position;
1951 :
1952 1876 : if (!(csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE))
1953 : {
1954 0 : log_error(LOG_LEVEL_HEADER,
1955 : "keep-alive support is disabled. Crunching: %s.", *header);
1956 0 : freez(*header);
1957 0 : return JB_ERR_OK;
1958 : }
1959 :
1960 : /* Check for parameter-less format "Keep-Alive: 100" */
1961 1876 : timeout_position = strstr(*header, ": ");
1962 1876 : if ((NULL == timeout_position)
1963 1113 : || (1 != sscanf(timeout_position, ": %u", &keep_alive_timeout)))
1964 : {
1965 : /* Assume parameter format "Keep-Alive: timeout=100" */
1966 1080 : timeout_position = strstr(*header, "timeout=");
1967 1080 : if ((NULL == timeout_position)
1968 64 : || (1 != sscanf(timeout_position, "timeout=%u", &keep_alive_timeout)))
1969 : {
1970 1057 : log_error(LOG_LEVEL_HEADER,
1971 : "Couldn't parse: '%s'. Using default timeout %u",
1972 1057 : *header, csp->config->keep_alive_timeout);
1973 1057 : freez(*header);
1974 :
1975 1057 : return JB_ERR_OK;
1976 : }
1977 : }
1978 :
1979 819 : if (keep_alive_timeout < csp->config->keep_alive_timeout)
1980 : {
1981 681 : log_error(LOG_LEVEL_HEADER,
1982 : "Reducing keep-alive timeout from %u to %u.",
1983 681 : csp->config->keep_alive_timeout, keep_alive_timeout);
1984 681 : csp->server_connection.keep_alive_timeout = keep_alive_timeout;
1985 : }
1986 : else
1987 : {
1988 : /* XXX: Is this log worthy? */
1989 138 : log_error(LOG_LEVEL_HEADER,
1990 : "Client keep-alive timeout is %u. Sticking with %u.",
1991 138 : keep_alive_timeout, csp->config->keep_alive_timeout);
1992 138 : freez(*header);
1993 : }
1994 :
1995 819 : return JB_ERR_OK;
1996 : }
1997 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1998 :
1999 :
2000 : /*********************************************************************
2001 : *
2002 : * Function : get_content_length
2003 : *
2004 : * Description : Gets the content length specified in a
2005 : * Content-Length header.
2006 : *
2007 : * Parameters :
2008 : * 1 : header_value = The Content-Length header value.
2009 : * 2 : length = Storage to return the value.
2010 : *
2011 : * Returns : JB_ERR_OK on success, or
2012 : * JB_ERR_PARSE if no value is recognized.
2013 : *
2014 : *********************************************************************/
2015 4293 : static jb_err get_content_length(const char *header_value, unsigned long long *length)
2016 : {
2017 : #ifdef _WIN32
2018 : #if SIZEOF_LONG_LONG < 8
2019 : #error sizeof(unsigned long long) too small
2020 : #endif
2021 : if (1 != sscanf(header_value, "%I64u", length))
2022 : #else
2023 4293 : if (1 != sscanf(header_value, "%llu", length))
2024 : #endif
2025 : {
2026 834 : return JB_ERR_PARSE;
2027 : }
2028 :
2029 3459 : return JB_ERR_OK;
2030 : }
2031 :
2032 :
2033 : /*********************************************************************
2034 : *
2035 : * Function : client_save_content_length
2036 : *
2037 : * Description : Save the Content-Length sent by the client.
2038 : *
2039 : * Parameters :
2040 : * 1 : csp = Current client state (buffers, headers, etc...)
2041 : * 2 : header = pointer to the Content-Length header
2042 : *
2043 : * Returns : JB_ERR_OK on success, or
2044 : * JB_ERR_MEMORY on out-of-memory error.
2045 : *
2046 : *********************************************************************/
2047 1447 : static jb_err client_save_content_length(struct client_state *csp, char **header)
2048 : {
2049 1447 : unsigned long long content_length = 0;
2050 : const char *header_value;
2051 :
2052 1447 : assert(*(*header+14) == ':');
2053 :
2054 1447 : header_value = *header + 15;
2055 1447 : if (JB_ERR_OK != get_content_length(header_value, &content_length))
2056 : {
2057 171 : log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2058 171 : freez(*header);
2059 : }
2060 : else
2061 : {
2062 1276 : csp->expected_client_content_length = content_length;
2063 : }
2064 :
2065 1447 : return JB_ERR_OK;
2066 : }
2067 :
2068 :
2069 : /*********************************************************************
2070 : *
2071 : * Function : client_connection
2072 : *
2073 : * Description : Makes sure a proper "Connection:" header is
2074 : * set and signals connection_header_adder
2075 : * to do nothing.
2076 : *
2077 : * Parameters :
2078 : * 1 : csp = Current client state (buffers, headers, etc...)
2079 : * 2 : header = On input, pointer to header to modify.
2080 : * On output, pointer to the modified header, or NULL
2081 : * to remove the header. This function frees the
2082 : * original string if necessary.
2083 : *
2084 : * Returns : JB_ERR_OK on success.
2085 : *
2086 : *********************************************************************/
2087 7873 : static jb_err client_connection(struct client_state *csp, char **header)
2088 : {
2089 : static const char connection_close[] = "Connection: close";
2090 :
2091 7873 : if (!strcmpic(*header, connection_close))
2092 : {
2093 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2094 477 : if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
2095 0 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
2096 : #ifdef FEATURE_HTTPS_INSPECTION
2097 0 : && !client_use_ssl(csp)
2098 : #endif
2099 : )
2100 : {
2101 0 : if (!strcmpic(csp->http->version, "HTTP/1.1"))
2102 : {
2103 0 : log_error(LOG_LEVEL_HEADER,
2104 : "Removing \'%s\' to imply keep-alive.", *header);
2105 0 : freez(*header);
2106 : /*
2107 : * While we imply keep-alive to the server,
2108 : * we have to remember that the client didn't.
2109 : */
2110 0 : csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2111 : }
2112 : else
2113 : {
2114 0 : char *old_header = *header;
2115 :
2116 0 : *header = strdup_or_die("Connection: keep-alive");
2117 0 : log_error(LOG_LEVEL_HEADER,
2118 : "Replaced: \'%s\' with \'%s\'", old_header, *header);
2119 0 : freez(old_header);
2120 : }
2121 : }
2122 : else
2123 : {
2124 477 : log_error(LOG_LEVEL_HEADER,
2125 : "Keeping the client header '%s' around. "
2126 : "The connection will not be kept alive.",
2127 : *header);
2128 477 : csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2129 : }
2130 : }
2131 7396 : else if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
2132 7396 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
2133 : {
2134 7378 : log_error(LOG_LEVEL_HEADER,
2135 : "Keeping the client header '%s' around. "
2136 : "The server connection will be kept alive if possible.",
2137 : *header);
2138 7378 : csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2139 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2140 : }
2141 : else
2142 : {
2143 18 : char *old_header = *header;
2144 :
2145 18 : *header = strdup_or_die(connection_close);
2146 18 : log_error(LOG_LEVEL_HEADER,
2147 : "Replaced: \'%s\' with \'%s\'", old_header, *header);
2148 18 : freez(old_header);
2149 : }
2150 :
2151 : /* Signal client_connection_header_adder() to return early. */
2152 7873 : csp->flags |= CSP_FLAG_CLIENT_CONNECTION_HEADER_SET;
2153 :
2154 7873 : return JB_ERR_OK;
2155 : }
2156 :
2157 :
2158 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2159 : /*********************************************************************
2160 : *
2161 : * Function : client_proxy_connection
2162 : *
2163 : * Description : Sets the CLIENT_CONNECTION_KEEP_ALIVE flag when
2164 : * appropriate and removes the Proxy-Connection
2165 : * header.
2166 : *
2167 : * Parameters :
2168 : * 1 : csp = Current client state (buffers, headers, etc...)
2169 : * 2 : header = On input, pointer to header to modify.
2170 : * On output, pointer to the modified header, or NULL
2171 : * to remove the header. This function frees the
2172 : * original string if necessary.
2173 : *
2174 : * Returns : JB_ERR_OK
2175 : *
2176 : *********************************************************************/
2177 2416 : static jb_err client_proxy_connection(struct client_state *csp, char **header)
2178 : {
2179 2416 : if (0 == (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
2180 227 : && (csp->http->ssl == 0)
2181 86 : && (NULL == strstr(*header, "close")))
2182 : {
2183 76 : log_error(LOG_LEVEL_HEADER,
2184 : "The client connection can be kept alive due to: %s", *header);
2185 76 : csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2186 : }
2187 2416 : crumble(csp, header);
2188 :
2189 2416 : return JB_ERR_OK;
2190 : }
2191 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2192 :
2193 :
2194 : /*********************************************************************
2195 : *
2196 : * Function : client_transfer_encoding
2197 : *
2198 : * Description : Raise the CSP_FLAG_CHUNKED_CLIENT_BODY flag if
2199 : * the request body is "chunked"
2200 : *
2201 : * XXX: Currently not called through sed() as we
2202 : * need the flag earlier on. Should be fixed.
2203 : *
2204 : * Parameters :
2205 : * 1 : csp = Current client state (buffers, headers, etc...)
2206 : * 2 : header = On input, pointer to header to modify.
2207 : * On output, pointer to the modified header, or NULL
2208 : * to remove the header. This function frees the
2209 : * original string if necessary.
2210 : *
2211 : * Returns : JB_ERR_OK on success, or
2212 : *
2213 : *********************************************************************/
2214 784 : jb_err client_transfer_encoding(struct client_state *csp, char **header)
2215 : {
2216 784 : if (strstr(*header, "chunked"))
2217 : {
2218 354 : csp->flags |= CSP_FLAG_CHUNKED_CLIENT_BODY;
2219 354 : log_error(LOG_LEVEL_HEADER, "Expecting chunked client body");
2220 : }
2221 :
2222 784 : return JB_ERR_OK;
2223 : }
2224 :
2225 :
2226 : /*********************************************************************
2227 : *
2228 : * Function : client_expect
2229 : *
2230 : * Description : Raise the CSP_FLAG_UNSUPPORTED_CLIENT_EXPECTATION
2231 : * if the Expect header value is unsupported.
2232 : *
2233 : * Rejecting unsupported expectations is a RFC 7231 5.1.1
2234 : * MAY and a RFC 2616 (obsolete) MUST.
2235 : *
2236 : * Parameters :
2237 : * 1 : csp = Current client state (buffers, headers, etc...)
2238 : * 2 : header = On input, pointer to header to modify.
2239 : * On output, pointer to the modified header, or NULL
2240 : * to remove the header. This function frees the
2241 : * original string if necessary.
2242 : *
2243 : * Returns : JB_ERR_OK on success, or
2244 : *
2245 : *********************************************************************/
2246 234 : jb_err client_expect(struct client_state *csp, char **header)
2247 : {
2248 234 : if (0 != strcmpic(*header, "Expect: 100-continue"))
2249 : {
2250 234 : csp->flags |= CSP_FLAG_UNSUPPORTED_CLIENT_EXPECTATION;
2251 234 : log_error(LOG_LEVEL_HEADER,
2252 : "Unsupported client expectaction: %s", *header);
2253 : }
2254 :
2255 234 : return JB_ERR_OK;
2256 :
2257 : }
2258 :
2259 :
2260 : /*********************************************************************
2261 : *
2262 : * Function : crumble
2263 : *
2264 : * Description : This is called if a header matches a pattern to "crunch"
2265 : *
2266 : * Parameters :
2267 : * 1 : csp = Current client state (buffers, headers, etc...)
2268 : * 2 : header = On input, pointer to header to modify.
2269 : * On output, pointer to the modified header, or NULL
2270 : * to remove the header. This function frees the
2271 : * original string if necessary.
2272 : *
2273 : * Returns : JB_ERR_OK on success, or
2274 : * JB_ERR_MEMORY on out-of-memory error.
2275 : *
2276 : *********************************************************************/
2277 2416 : static jb_err crumble(struct client_state *csp, char **header)
2278 : {
2279 : (void)csp;
2280 2416 : log_error(LOG_LEVEL_HEADER, "crumble crunched: %s!", *header);
2281 2416 : freez(*header);
2282 2416 : return JB_ERR_OK;
2283 : }
2284 :
2285 :
2286 : /*********************************************************************
2287 : *
2288 : * Function : crunch_server_header
2289 : *
2290 : * Description : Crunch server header if it matches a string supplied by the
2291 : * user. Called from `sed'.
2292 : *
2293 : * Parameters :
2294 : * 1 : csp = Current client state (buffers, headers, etc...)
2295 : * 2 : header = On input, pointer to header to modify.
2296 : * On output, pointer to the modified header, or NULL
2297 : * to remove the header. This function frees the
2298 : * original string if necessary.
2299 : *
2300 : * Returns : JB_ERR_OK on success and always succeeds
2301 : *
2302 : *********************************************************************/
2303 81357 : static jb_err crunch_server_header(struct client_state *csp, char **header)
2304 : {
2305 : const char *crunch_pattern;
2306 :
2307 : /* Do we feel like crunching? */
2308 81357 : if ((csp->action->flags & ACTION_CRUNCH_SERVER_HEADER))
2309 : {
2310 76061 : crunch_pattern = csp->action->string[ACTION_STRING_SERVER_HEADER];
2311 :
2312 : /* Is the current header the lucky one? */
2313 76061 : if (strstr(*header, crunch_pattern))
2314 : {
2315 34 : log_error(LOG_LEVEL_HEADER, "Crunching server header: %s (contains: %s)", *header, crunch_pattern);
2316 34 : freez(*header);
2317 : }
2318 : }
2319 :
2320 81357 : return JB_ERR_OK;
2321 : }
2322 :
2323 :
2324 : /*********************************************************************
2325 : *
2326 : * Function : server_content_type
2327 : *
2328 : * Description : Set the content-type for filterable types (text/.*,
2329 : * .*xml.*, .*script.* and image/gif) unless filtering has been
2330 : * forbidden (CT_TABOO) while parsing earlier headers.
2331 : * NOTE: Since text/plain is commonly used by web servers
2332 : * for files whose correct type is unknown, we don't
2333 : * set CT_TEXT for it.
2334 : *
2335 : * Parameters :
2336 : * 1 : csp = Current client state (buffers, headers, etc...)
2337 : * 2 : header = On input, pointer to header to modify.
2338 : * On output, pointer to the modified header, or NULL
2339 : * to remove the header. This function frees the
2340 : * original string if necessary.
2341 : *
2342 : * Returns : JB_ERR_OK on success, or
2343 : * JB_ERR_MEMORY on out-of-memory error.
2344 : *
2345 : *********************************************************************/
2346 3705 : static jb_err server_content_type(struct client_state *csp, char **header)
2347 : {
2348 : /* Remove header if it isn't the first Content-Type header */
2349 3705 : if ((csp->content_type & CT_DECLARED))
2350 : {
2351 2012 : if (content_filters_enabled(csp->action))
2352 : {
2353 : /*
2354 : * Making sure the client interprets the content the same way
2355 : * Privoxy did is only relevant if Privoxy modified it.
2356 : *
2357 : * Checking for this is "hard" as it's not yet known when
2358 : * this function is called, thus go shopping and and just
2359 : * check if Privoxy could filter it.
2360 : *
2361 : * The main thing is that we don't mess with the headers
2362 : * unless the user signalled that it's acceptable.
2363 : */
2364 1562 : log_error(LOG_LEVEL_HEADER,
2365 : "Multiple Content-Type headers detected. "
2366 : "Removing and ignoring: %s",
2367 : *header);
2368 1562 : freez(*header);
2369 : }
2370 2012 : return JB_ERR_OK;
2371 : }
2372 :
2373 : /*
2374 : * Signal that the Content-Type has been set.
2375 : */
2376 1693 : csp->content_type |= CT_DECLARED;
2377 :
2378 1693 : if (!(csp->content_type & CT_TABOO))
2379 : {
2380 : /*
2381 : * XXX: The assumption that text/plain is a sign of
2382 : * binary data seems to be somewhat unreasonable nowadays
2383 : * and should be dropped after 3.0.8 is out.
2384 : */
2385 1680 : if ((strstr(*header, "text/") && !strstr(*header, "plain"))
2386 1420 : || strstr(*header, "xml")
2387 1410 : || strstr(*header, "script"))
2388 : {
2389 305 : csp->content_type |= CT_TEXT;
2390 : }
2391 1375 : else if (strstr(*header, "image/gif"))
2392 : {
2393 667 : csp->content_type |= CT_GIF;
2394 : }
2395 : }
2396 :
2397 : /*
2398 : * Are we messing with the content type?
2399 : */
2400 1693 : if (csp->action->flags & ACTION_CONTENT_TYPE_OVERWRITE)
2401 : {
2402 : /*
2403 : * Make sure the user doesn't accidentally
2404 : * change the content type of binary documents.
2405 : */
2406 2 : if ((csp->content_type & CT_TEXT) || (csp->action->flags & ACTION_FORCE_TEXT_MODE))
2407 1 : {
2408 : jb_err err;
2409 1 : freez(*header);
2410 1 : *header = strdup_or_die("Content-Type: ");
2411 :
2412 1 : err = string_append(header, csp->action->string[ACTION_STRING_CONTENT_TYPE]);
2413 1 : if (JB_ERR_OK != err)
2414 : {
2415 0 : log_error(LOG_LEVEL_HEADER, "Insufficient memory to replace Content-Type!");
2416 0 : return JB_ERR_MEMORY;
2417 : }
2418 1 : log_error(LOG_LEVEL_HEADER, "Modified: %s!", *header);
2419 : }
2420 : else
2421 : {
2422 1 : log_error(LOG_LEVEL_HEADER, "%s not replaced. "
2423 : "It doesn't look like a content type that should be filtered. "
2424 : "Enable force-text-mode if you know what you're doing.", *header);
2425 : }
2426 : }
2427 :
2428 1693 : return JB_ERR_OK;
2429 : }
2430 :
2431 :
2432 : /*********************************************************************
2433 : *
2434 : * Function : server_transfer_coding
2435 : *
2436 : * Description : - Prohibit filtering (CT_TABOO) if transfer coding compresses
2437 : * - Raise the CSP_FLAG_CHUNKED flag if coding is "chunked"
2438 : * - Remove header if body was chunked but has been
2439 : * de-chunked for filtering.
2440 : *
2441 : * Parameters :
2442 : * 1 : csp = Current client state (buffers, headers, etc...)
2443 : * 2 : header = On input, pointer to header to modify.
2444 : * On output, pointer to the modified header, or NULL
2445 : * to remove the header. This function frees the
2446 : * original string if necessary.
2447 : *
2448 : * Returns : JB_ERR_OK on success, or
2449 : * JB_ERR_MEMORY on out-of-memory error.
2450 : *
2451 : *********************************************************************/
2452 6062 : static jb_err server_transfer_coding(struct client_state *csp, char **header)
2453 : {
2454 : /*
2455 : * Turn off pcrs and gif filtering if body compressed
2456 : */
2457 6062 : if (strstr(*header, "gzip") || strstr(*header, "compress") || strstr(*header, "deflate"))
2458 : {
2459 : #ifdef FEATURE_ZLIB
2460 : /*
2461 : * XXX: Added to test if we could use CT_GZIP and CT_DEFLATE here.
2462 : */
2463 558 : log_error(LOG_LEVEL_INFO, "Marking content type for %s as CT_TABOO because of %s.",
2464 : csp->http->cmd, *header);
2465 : #endif /* def FEATURE_ZLIB */
2466 558 : csp->content_type = CT_TABOO;
2467 : }
2468 :
2469 : /*
2470 : * Raise flag if body chunked
2471 : */
2472 6062 : if (strstr(*header, "chunked"))
2473 : {
2474 5140 : csp->flags |= CSP_FLAG_CHUNKED;
2475 :
2476 : /*
2477 : * If the body was modified, it has been de-chunked first
2478 : * and the header must be removed.
2479 : *
2480 : * FIXME: If there is more than one transfer encoding,
2481 : * only the "chunked" part should be removed here.
2482 : */
2483 5140 : if (csp->flags & CSP_FLAG_MODIFIED)
2484 : {
2485 1186 : log_error(LOG_LEVEL_HEADER, "Removing: %s", *header);
2486 1186 : freez(*header);
2487 : }
2488 : }
2489 :
2490 6062 : return JB_ERR_OK;
2491 : }
2492 :
2493 :
2494 : /*********************************************************************
2495 : *
2496 : * Function : server_content_encoding
2497 : *
2498 : * Description : Used to check if the content is compressed, and if
2499 : * FEATURE_ZLIB is disabled, filtering is disabled as
2500 : * well.
2501 : *
2502 : * If FEATURE_ZLIB is enabled and the compression type
2503 : * supported, the content is marked for decompression.
2504 : *
2505 : * XXX: Doesn't properly deal with multiple or with
2506 : * unsupported but unknown encodings.
2507 : * Is case-sensitive but shouldn't be.
2508 : *
2509 : * Parameters :
2510 : * 1 : csp = Current client state (buffers, headers, etc...)
2511 : * 2 : header = On input, pointer to header to modify.
2512 : * On output, pointer to the modified header, or NULL
2513 : * to remove the header. This function frees the
2514 : * original string if necessary.
2515 : *
2516 : * Returns : JB_ERR_OK on success, or
2517 : * JB_ERR_MEMORY on out-of-memory error.
2518 : *
2519 : *********************************************************************/
2520 2178 : static jb_err server_content_encoding(struct client_state *csp, char **header)
2521 : {
2522 : #ifdef FEATURE_ZLIB
2523 2178 : if (strstr(*header, "sdch"))
2524 : {
2525 : /*
2526 : * Shared Dictionary Compression over HTTP isn't supported,
2527 : * filtering it anyway is pretty much guaranteed to mess up
2528 : * the encoding.
2529 : */
2530 157 : csp->content_type |= CT_TABOO;
2531 :
2532 : /*
2533 : * Log a warning if the user expects the content to be filtered.
2534 : */
2535 157 : if (content_filters_enabled(csp->action))
2536 : {
2537 66 : log_error(LOG_LEVEL_INFO,
2538 : "SDCH-compressed content detected, content filtering disabled. "
2539 : "Consider suppressing SDCH offers made by the client.");
2540 : }
2541 : }
2542 2021 : else if (strstr(*header, "gzip"))
2543 : {
2544 : /* Mark for gzip decompression */
2545 598 : csp->content_type |= CT_GZIP;
2546 : }
2547 1423 : else if (strstr(*header, "deflate"))
2548 : {
2549 : /* Mark for zlib decompression */
2550 68 : csp->content_type |= CT_DEFLATE;
2551 : }
2552 1355 : else if (strstr(*header, "br"))
2553 : {
2554 : #ifdef FEATURE_BROTLI
2555 : /* Mark for Brotli decompression */
2556 909 : csp->content_type |= CT_BROTLI;
2557 : #else
2558 : csp->content_type |= CT_TABOO;
2559 : #endif
2560 : }
2561 446 : else if (strstr(*header, "compress"))
2562 : {
2563 : /*
2564 : * We can't decompress this; therefore we can't filter
2565 : * it either.
2566 : */
2567 69 : csp->content_type |= CT_TABOO;
2568 : }
2569 : #else /* !defined(FEATURE_ZLIB) */
2570 : /*
2571 : * XXX: Using a black list here isn't the right approach.
2572 : *
2573 : * In case of SDCH, building with zlib support isn't
2574 : * going to help.
2575 : */
2576 : if (strstr(*header, "gzip") ||
2577 : strstr(*header, "compress") ||
2578 : strstr(*header, "deflate") ||
2579 : strstr(*header, "sdch"))
2580 : {
2581 : /*
2582 : * Body is compressed, turn off pcrs and gif filtering.
2583 : */
2584 : csp->content_type |= CT_TABOO;
2585 :
2586 : /*
2587 : * Log a warning if the user expects the content to be filtered.
2588 : */
2589 : if (content_filters_enabled(csp->action))
2590 : {
2591 : log_error(LOG_LEVEL_INFO,
2592 : "Compressed content detected, content filtering disabled. "
2593 : "Consider recompiling Privoxy with zlib support or "
2594 : "enable the prevent-compression action.");
2595 : }
2596 : }
2597 : #endif /* defined(FEATURE_ZLIB) */
2598 :
2599 2178 : return JB_ERR_OK;
2600 :
2601 : }
2602 :
2603 :
2604 : #ifdef FEATURE_ZLIB
2605 : /*********************************************************************
2606 : *
2607 : * Function : server_adjust_content_encoding
2608 : *
2609 : * Description : Remove the Content-Encoding header if the
2610 : * decompression was successful and the content
2611 : * has been modified.
2612 : *
2613 : * Parameters :
2614 : * 1 : csp = Current client state (buffers, headers, etc...)
2615 : * 2 : header = On input, pointer to header to modify.
2616 : * On output, pointer to the modified header, or NULL
2617 : * to remove the header. This function frees the
2618 : * original string if necessary.
2619 : *
2620 : * Returns : JB_ERR_OK on success, or
2621 : * JB_ERR_MEMORY on out-of-memory error.
2622 : *
2623 : *********************************************************************/
2624 965 : static jb_err server_adjust_content_encoding(struct client_state *csp, char **header)
2625 : {
2626 965 : if ((csp->flags & CSP_FLAG_MODIFIED)
2627 511 : && ((csp->content_type & (CT_GZIP | CT_DEFLATE))
2628 : #ifdef FEATURE_BROTLI
2629 465 : || (csp->content_type & CT_BROTLI)
2630 : #endif
2631 : )
2632 : )
2633 : {
2634 : /*
2635 : * We successfully decompressed the content,
2636 : * and have to clean the header now, so the
2637 : * client no longer expects compressed data.
2638 : *
2639 : * XXX: There is a difference between cleaning
2640 : * and removing it completely.
2641 : */
2642 270 : log_error(LOG_LEVEL_HEADER, "Crunching: %s", *header);
2643 270 : freez(*header);
2644 : }
2645 :
2646 965 : return JB_ERR_OK;
2647 :
2648 : }
2649 : #endif /* defined(FEATURE_ZLIB) */
2650 :
2651 :
2652 : /*********************************************************************
2653 : *
2654 : * Function : header_adjust_content_length
2655 : *
2656 : * Description : Replace given header with new Content-Length header.
2657 : *
2658 : * Parameters :
2659 : * 1 : header = On input, pointer to header to modify.
2660 : * On output, pointer to the modified header, or NULL
2661 : * to remove the header. This function frees the
2662 : * original string if necessary.
2663 : * 2 : content_length = content length value to set
2664 : *
2665 : * Returns : JB_ERR_OK on success, or
2666 : * JB_ERR_MEMORY on out-of-memory error.
2667 : *
2668 : *********************************************************************/
2669 446 : jb_err header_adjust_content_length(char **header, size_t content_length)
2670 : {
2671 446 : const size_t header_length = 50;
2672 446 : freez(*header);
2673 446 : *header = malloc(header_length);
2674 446 : if (*header == NULL)
2675 : {
2676 0 : return JB_ERR_MEMORY;
2677 : }
2678 446 : create_content_length_header(content_length, *header, header_length);
2679 446 : return JB_ERR_OK;
2680 : }
2681 :
2682 :
2683 : /*********************************************************************
2684 : *
2685 : * Function : server_adjust_content_length
2686 : *
2687 : * Description : Adjust Content-Length header if we modified
2688 : * the body.
2689 : *
2690 : * Parameters :
2691 : * 1 : csp = Current client state (buffers, headers, etc...)
2692 : * 2 : header = On input, pointer to header to modify.
2693 : * On output, pointer to the modified header, or NULL
2694 : * to remove the header. This function frees the
2695 : * original string if necessary.
2696 : *
2697 : * Returns : JB_ERR_OK on success, or
2698 : * JB_ERR_MEMORY on out-of-memory error.
2699 : *
2700 : *********************************************************************/
2701 501 : static jb_err server_adjust_content_length(struct client_state *csp, char **header)
2702 : {
2703 : /* Regenerate header if the content was modified. */
2704 501 : if (csp->flags & CSP_FLAG_MODIFIED)
2705 : {
2706 206 : if (JB_ERR_OK != header_adjust_content_length(header, csp->content_length))
2707 : {
2708 0 : return JB_ERR_MEMORY;
2709 : }
2710 206 : log_error(LOG_LEVEL_HEADER,
2711 : "Adjusted Content-Length to %llu", csp->content_length);
2712 : }
2713 :
2714 501 : return JB_ERR_OK;
2715 : }
2716 :
2717 :
2718 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2719 : /*********************************************************************
2720 : *
2721 : * Function : server_save_content_length
2722 : *
2723 : * Description : Save the Content-Length sent by the server.
2724 : *
2725 : * Parameters :
2726 : * 1 : csp = Current client state (buffers, headers, etc...)
2727 : * 2 : header = On input, pointer to header to modify.
2728 : * On output, pointer to the modified header, or NULL
2729 : * to remove the header. This function frees the
2730 : * original string if necessary.
2731 : *
2732 : * Returns : JB_ERR_OK on success, or
2733 : * JB_ERR_MEMORY on out-of-memory error.
2734 : *
2735 : *********************************************************************/
2736 1541 : static jb_err server_save_content_length(struct client_state *csp, char **header)
2737 : {
2738 1541 : unsigned long long content_length = 0;
2739 : const char *header_value;
2740 :
2741 1541 : assert(*(*header+14) == ':');
2742 :
2743 1541 : header_value = *header + 15;
2744 1541 : if (JB_ERR_OK != get_content_length(header_value, &content_length))
2745 : {
2746 515 : log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
2747 515 : freez(*header);
2748 : }
2749 : else
2750 : {
2751 1026 : csp->expected_content_length = content_length;
2752 1026 : csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
2753 1026 : csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2754 : }
2755 :
2756 1541 : return JB_ERR_OK;
2757 : }
2758 : #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2759 :
2760 :
2761 : /*********************************************************************
2762 : *
2763 : * Function : server_content_md5
2764 : *
2765 : * Description : Crumble any Content-MD5 headers if the document was
2766 : * modified. FIXME: Should we re-compute instead?
2767 : *
2768 : * Parameters :
2769 : * 1 : csp = Current client state (buffers, headers, etc...)
2770 : * 2 : header = On input, pointer to header to modify.
2771 : * On output, pointer to the modified header, or NULL
2772 : * to remove the header. This function frees the
2773 : * original string if necessary.
2774 : *
2775 : * Returns : JB_ERR_OK on success, or
2776 : * JB_ERR_MEMORY on out-of-memory error.
2777 : *
2778 : *********************************************************************/
2779 72 : static jb_err server_content_md5(struct client_state *csp, char **header)
2780 : {
2781 72 : if (csp->flags & CSP_FLAG_MODIFIED)
2782 : {
2783 0 : log_error(LOG_LEVEL_HEADER, "Crunching Content-MD5");
2784 0 : freez(*header);
2785 : }
2786 :
2787 72 : return JB_ERR_OK;
2788 : }
2789 :
2790 :
2791 : /*********************************************************************
2792 : *
2793 : * Function : server_content_disposition
2794 : *
2795 : * Description : If enabled, blocks or modifies the "Content-Disposition" header.
2796 : * Called from `sed'.
2797 : *
2798 : * Parameters :
2799 : * 1 : csp = Current client state (buffers, headers, etc...)
2800 : * 2 : header = On input, pointer to header to modify.
2801 : * On output, pointer to the modified header, or NULL
2802 : * to remove the header. This function frees the
2803 : * original string if necessary.
2804 : *
2805 : * Returns : JB_ERR_OK on success, or
2806 : * JB_ERR_MEMORY on out-of-memory error.
2807 : *
2808 : *********************************************************************/
2809 100 : static jb_err server_content_disposition(struct client_state *csp, char **header)
2810 : {
2811 : const char *newval;
2812 :
2813 : /*
2814 : * Are we messing with the Content-Disposition header?
2815 : */
2816 100 : if ((csp->action->flags & ACTION_HIDE_CONTENT_DISPOSITION) == 0)
2817 : {
2818 : /* Me tinks not */
2819 34 : return JB_ERR_OK;
2820 : }
2821 :
2822 66 : newval = csp->action->string[ACTION_STRING_CONTENT_DISPOSITION];
2823 :
2824 66 : if ((newval == NULL) || (0 == strcmpic(newval, "block")))
2825 : {
2826 : /*
2827 : * Blocking content-disposition header
2828 : */
2829 0 : log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2830 0 : freez(*header);
2831 0 : return JB_ERR_OK;
2832 : }
2833 : else
2834 : {
2835 : /*
2836 : * Replacing Content-Disposition header
2837 : */
2838 66 : freez(*header);
2839 66 : *header = strdup("Content-Disposition: ");
2840 66 : string_append(header, newval);
2841 :
2842 66 : if (*header != NULL)
2843 : {
2844 66 : log_error(LOG_LEVEL_HEADER,
2845 : "Content-Disposition header crunched and replaced with: %s", *header);
2846 : }
2847 : }
2848 66 : return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
2849 : }
2850 :
2851 :
2852 : /*********************************************************************
2853 : *
2854 : * Function : server_last_modified
2855 : *
2856 : * Description : Changes Last-Modified header to the actual date
2857 : * to help hide-if-modified-since.
2858 : * Called from `sed'.
2859 : *
2860 : * Parameters :
2861 : * 1 : csp = Current client state (buffers, headers, etc...)
2862 : * 2 : header = On input, pointer to header to modify.
2863 : * On output, pointer to the modified header, or NULL
2864 : * to remove the header. This function frees the
2865 : * original string if necessary.
2866 : *
2867 : * Returns : JB_ERR_OK on success, or
2868 : * JB_ERR_MEMORY on out-of-memory error.
2869 : *
2870 : *********************************************************************/
2871 2351 : static jb_err server_last_modified(struct client_state *csp, char **header)
2872 : {
2873 : const char *newval;
2874 : time_t last_modified;
2875 : char newheader[50];
2876 :
2877 : /*
2878 : * Are we messing with the Last-Modified header?
2879 : */
2880 2351 : if ((csp->action->flags & ACTION_OVERWRITE_LAST_MODIFIED) == 0)
2881 : {
2882 : /*Nope*/
2883 289 : return JB_ERR_OK;
2884 : }
2885 :
2886 2062 : newval = csp->action->string[ACTION_STRING_LAST_MODIFIED];
2887 :
2888 2062 : if (0 == strcmpic(newval, "block"))
2889 : {
2890 : /*
2891 : * Blocking Last-Modified header. Useless but why not.
2892 : */
2893 0 : log_error(LOG_LEVEL_HEADER, "Crunching %s!", *header);
2894 0 : freez(*header);
2895 0 : return JB_ERR_OK;
2896 : }
2897 2062 : else if (0 == strcmpic(newval, "reset-to-request-time"))
2898 : {
2899 : /*
2900 : * Setting Last-Modified Header to now.
2901 : */
2902 : char buf[30];
2903 0 : get_http_time(0, buf, sizeof(buf));
2904 0 : freez(*header);
2905 0 : *header = strdup("Last-Modified: ");
2906 0 : string_append(header, buf);
2907 :
2908 0 : if (*header == NULL)
2909 : {
2910 0 : log_error(LOG_LEVEL_HEADER, "Insufficient memory. Last-Modified header got lost, boohoo.");
2911 : }
2912 : else
2913 : {
2914 0 : log_error(LOG_LEVEL_HEADER, "Reset to present time: %s", *header);
2915 : }
2916 : }
2917 2062 : else if (0 == strcmpic(newval, "randomize"))
2918 : {
2919 2062 : log_error(LOG_LEVEL_HEADER, "Randomizing: %s", *header);
2920 :
2921 2062 : if (JB_ERR_OK != parse_time_header(*header, &last_modified))
2922 : {
2923 1296 : log_error(LOG_LEVEL_HEADER,
2924 : "Couldn't parse time in %s (crunching!)", *header);
2925 1296 : freez(*header);
2926 : }
2927 : else
2928 : {
2929 : time_t now;
2930 766 : struct tm *timeptr = NULL;
2931 : long int rtime;
2932 : struct tm gmt;
2933 :
2934 766 : now = time(NULL);
2935 766 : rtime = (long int)difftime(now, last_modified);
2936 766 : if (rtime)
2937 : {
2938 : long int days, hours, minutes, seconds;
2939 766 : const int negative_delta = (rtime < 0);
2940 :
2941 766 : if (negative_delta)
2942 : {
2943 92 : rtime *= -1;
2944 92 : log_error(LOG_LEVEL_HEADER, "Server time in the future.");
2945 : }
2946 766 : rtime = pick_from_range(rtime);
2947 766 : if (negative_delta)
2948 : {
2949 92 : rtime *= -1;
2950 : }
2951 766 : last_modified += rtime;
2952 766 : timeptr = privoxy_gmtime_r(&last_modified, &gmt);
2953 766 : if ((NULL == timeptr) || !strftime(newheader,
2954 : sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
2955 : {
2956 0 : log_error(LOG_LEVEL_ERROR,
2957 : "Randomizing '%s' failed. Crunching the header without replacement.",
2958 : *header);
2959 0 : freez(*header);
2960 0 : return JB_ERR_OK;
2961 : }
2962 766 : freez(*header);
2963 766 : *header = strdup("Last-Modified: ");
2964 766 : string_append(header, newheader);
2965 :
2966 766 : if (*header == NULL)
2967 : {
2968 0 : log_error(LOG_LEVEL_ERROR, "Insufficient memory, header crunched without replacement.");
2969 0 : return JB_ERR_MEMORY;
2970 : }
2971 :
2972 766 : days = rtime / (3600 * 24);
2973 766 : hours = rtime / 3600 % 24;
2974 766 : minutes = rtime / 60 % 60;
2975 766 : seconds = rtime % 60;
2976 :
2977 766 : log_error(LOG_LEVEL_HEADER,
2978 : "Randomized: %s (added %ld da%s %ld hou%s %ld minut%s %ld second%s",
2979 : *header, days, (days == 1) ? "y" : "ys", hours, (hours == 1) ? "r" : "rs",
2980 : minutes, (minutes == 1) ? "e" : "es", seconds, (seconds == 1) ? ")" : "s)");
2981 : }
2982 : else
2983 : {
2984 0 : log_error(LOG_LEVEL_HEADER, "Randomized ... or not. No time difference to work with.");
2985 : }
2986 : }
2987 : }
2988 :
2989 2062 : return JB_ERR_OK;
2990 : }
2991 :
2992 :
2993 : /*********************************************************************
2994 : *
2995 : * Function : client_accept_encoding
2996 : *
2997 : * Description : Rewrite the client's Accept-Encoding header so that
2998 : * if doesn't allow compression, if the action applies.
2999 : * Note: For HTTP/1.0 the absence of the header is enough.
3000 : *
3001 : * Parameters :
3002 : * 1 : csp = Current client state (buffers, headers, etc...)
3003 : * 2 : header = On input, pointer to header to modify.
3004 : * On output, pointer to the modified header, or NULL
3005 : * to remove the header. This function frees the
3006 : * original string if necessary.
3007 : *
3008 : * Returns : JB_ERR_OK on success, or
3009 : * JB_ERR_MEMORY on out-of-memory error.
3010 : *
3011 : *********************************************************************/
3012 3114 : static jb_err client_accept_encoding(struct client_state *csp, char **header)
3013 : {
3014 : #ifdef FEATURE_COMPRESSION
3015 3114 : if ((csp->config->feature_flags & RUNTIME_FEATURE_COMPRESSION)
3016 3114 : && strstr(*header, "deflate"))
3017 : {
3018 2029 : csp->flags |= CSP_FLAG_CLIENT_SUPPORTS_DEFLATE;
3019 : }
3020 : #endif
3021 3114 : if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
3022 : {
3023 0 : log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress content");
3024 0 : freez(*header);
3025 : }
3026 :
3027 3114 : return JB_ERR_OK;
3028 : }
3029 :
3030 :
3031 : /*********************************************************************
3032 : *
3033 : * Function : client_te
3034 : *
3035 : * Description : Rewrite the client's TE header so that
3036 : * if doesn't allow compression, if the action applies.
3037 : *
3038 : * Parameters :
3039 : * 1 : csp = Current client state (buffers, headers, etc...)
3040 : * 2 : header = On input, pointer to header to modify.
3041 : * On output, pointer to the modified header, or NULL
3042 : * to remove the header. This function frees the
3043 : * original string if necessary.
3044 : *
3045 : * Returns : JB_ERR_OK on success, or
3046 : * JB_ERR_MEMORY on out-of-memory error.
3047 : *
3048 : *********************************************************************/
3049 102 : static jb_err client_te(struct client_state *csp, char **header)
3050 : {
3051 102 : if ((csp->action->flags & ACTION_NO_COMPRESSION) != 0)
3052 : {
3053 0 : freez(*header);
3054 0 : log_error(LOG_LEVEL_HEADER, "Suppressed offer to compress transfer");
3055 : }
3056 :
3057 102 : return JB_ERR_OK;
3058 : }
3059 :
3060 :
3061 : /*********************************************************************
3062 : *
3063 : * Function : client_referrer
3064 : *
3065 : * Description : Handle the "referer" config setting properly.
3066 : * Called from `sed'.
3067 : *
3068 : * Parameters :
3069 : * 1 : csp = Current client state (buffers, headers, etc...)
3070 : * 2 : header = On input, pointer to header to modify.
3071 : * On output, pointer to the modified header, or NULL
3072 : * to remove the header. This function frees the
3073 : * original string if necessary.
3074 : *
3075 : * Returns : JB_ERR_OK on success, or
3076 : * JB_ERR_MEMORY on out-of-memory error.
3077 : *
3078 : *********************************************************************/
3079 11017 : static jb_err client_referrer(struct client_state *csp, char **header)
3080 : {
3081 : const char *parameter;
3082 : /* booleans for parameters we have to check multiple times */
3083 : int parameter_conditional_block;
3084 : int parameter_conditional_forge;
3085 :
3086 : #ifdef FEATURE_FORCE_LOAD
3087 : /*
3088 : * Since the referrer can include the prefix even
3089 : * if the request itself is non-forced, we must
3090 : * clean it unconditionally.
3091 : *
3092 : * XXX: strclean is too broad
3093 : */
3094 11017 : strclean(*header, FORCE_PREFIX);
3095 : #endif /* def FEATURE_FORCE_LOAD */
3096 :
3097 11017 : if ((csp->action->flags & ACTION_HIDE_REFERER) == 0)
3098 : {
3099 : /* Nothing left to do */
3100 9447 : return JB_ERR_OK;
3101 : }
3102 :
3103 1570 : parameter = csp->action->string[ACTION_STRING_REFERER];
3104 1570 : assert(parameter != NULL);
3105 1570 : parameter_conditional_block = (0 == strcmpic(parameter, "conditional-block"));
3106 1570 : parameter_conditional_forge = (0 == strcmpic(parameter, "conditional-forge"));
3107 :
3108 1570 : if (!parameter_conditional_block && !parameter_conditional_forge)
3109 : {
3110 : /*
3111 : * As conditional-block and conditional-forge are the only
3112 : * parameters that rely on the original referrer, we can
3113 : * remove it now for all the others.
3114 : */
3115 1479 : freez(*header);
3116 : }
3117 :
3118 1570 : if (0 == strcmpic(parameter, "block"))
3119 : {
3120 0 : log_error(LOG_LEVEL_HEADER, "Referer crunched!");
3121 0 : return JB_ERR_OK;
3122 : }
3123 1570 : else if (parameter_conditional_block || parameter_conditional_forge)
3124 : {
3125 91 : return handle_conditional_hide_referrer_parameter(header,
3126 91 : csp->http->hostport, parameter_conditional_block);
3127 : }
3128 1479 : else if (0 == strcmpic(parameter, "forge"))
3129 : {
3130 1441 : return create_forged_referrer(header, csp->http->hostport);
3131 : }
3132 : else
3133 : {
3134 : /* interpret parameter as user-supplied referer to fake */
3135 38 : return create_fake_referrer(header, parameter);
3136 : }
3137 : }
3138 :
3139 :
3140 : /*********************************************************************
3141 : *
3142 : * Function : client_accept_language
3143 : *
3144 : * Description : Handle the "Accept-Language" config setting properly.
3145 : * Called from `sed'.
3146 : *
3147 : * Parameters :
3148 : * 1 : csp = Current client state (buffers, headers, etc...)
3149 : * 2 : header = On input, pointer to header to modify.
3150 : * On output, pointer to the modified header, or NULL
3151 : * to remove the header. This function frees the
3152 : * original string if necessary.
3153 : *
3154 : * Returns : JB_ERR_OK on success, or
3155 : * JB_ERR_MEMORY on out-of-memory error.
3156 : *
3157 : *********************************************************************/
3158 1558 : static jb_err client_accept_language(struct client_state *csp, char **header)
3159 : {
3160 : const char *newval;
3161 :
3162 : /*
3163 : * Are we messing with the Accept-Language?
3164 : */
3165 1558 : if ((csp->action->flags & ACTION_HIDE_ACCEPT_LANGUAGE) == 0)
3166 : {
3167 : /*I don't think so*/
3168 1558 : return JB_ERR_OK;
3169 : }
3170 :
3171 0 : newval = csp->action->string[ACTION_STRING_LANGUAGE];
3172 :
3173 0 : if ((newval == NULL) || (0 == strcmpic(newval, "block")))
3174 : {
3175 : /*
3176 : * Blocking Accept-Language header
3177 : */
3178 0 : log_error(LOG_LEVEL_HEADER, "Crunching Accept-Language!");
3179 0 : freez(*header);
3180 0 : return JB_ERR_OK;
3181 : }
3182 : else
3183 : {
3184 : /*
3185 : * Replacing Accept-Language header
3186 : */
3187 0 : freez(*header);
3188 0 : *header = strdup("Accept-Language: ");
3189 0 : string_append(header, newval);
3190 :
3191 0 : if (*header == NULL)
3192 : {
3193 0 : log_error(LOG_LEVEL_ERROR,
3194 : "Insufficient memory. Accept-Language header crunched without replacement.");
3195 : }
3196 : else
3197 : {
3198 0 : log_error(LOG_LEVEL_HEADER,
3199 : "Accept-Language header crunched and replaced with: %s", *header);
3200 : }
3201 : }
3202 0 : return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
3203 : }
3204 :
3205 :
3206 : /*********************************************************************
3207 : *
3208 : * Function : crunch_client_header
3209 : *
3210 : * Description : Crunch client header if it matches a string supplied by the
3211 : * user. Called from `sed'.
3212 : *
3213 : * Parameters :
3214 : * 1 : csp = Current client state (buffers, headers, etc...)
3215 : * 2 : header = On input, pointer to header to modify.
3216 : * On output, pointer to the modified header, or NULL
3217 : * to remove the header. This function frees the
3218 : * original string if necessary.
3219 : *
3220 : * Returns : JB_ERR_OK on success and always succeeds
3221 : *
3222 : *********************************************************************/
3223 316379 : static jb_err crunch_client_header(struct client_state *csp, char **header)
3224 : {
3225 : const char *crunch_pattern;
3226 :
3227 : /* Do we feel like crunching? */
3228 316379 : if ((csp->action->flags & ACTION_CRUNCH_CLIENT_HEADER))
3229 : {
3230 158577 : crunch_pattern = csp->action->string[ACTION_STRING_CLIENT_HEADER];
3231 :
3232 : /* Is the current header the lucky one? */
3233 158577 : if (strstr(*header, crunch_pattern))
3234 : {
3235 52 : log_error(LOG_LEVEL_HEADER, "Crunching client header: %s (contains: %s)", *header, crunch_pattern);
3236 52 : freez(*header);
3237 : }
3238 : }
3239 316379 : return JB_ERR_OK;
3240 : }
3241 :
3242 :
3243 : /*********************************************************************
3244 : *
3245 : * Function : client_uagent
3246 : *
3247 : * Description : Handle the "user-agent" config setting properly
3248 : * and remember its original value to enable browser
3249 : * bug workarounds. Called from `sed'.
3250 : *
3251 : * Parameters :
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.
3257 : *
3258 : * Returns : JB_ERR_OK on success, or
3259 : * JB_ERR_MEMORY on out-of-memory error.
3260 : *
3261 : *********************************************************************/
3262 19626 : static jb_err client_uagent(struct client_state *csp, char **header)
3263 : {
3264 : const char *newval;
3265 :
3266 19626 : if ((csp->action->flags & ACTION_HIDE_USER_AGENT) == 0)
3267 : {
3268 597 : return JB_ERR_OK;
3269 : }
3270 :
3271 19029 : newval = csp->action->string[ACTION_STRING_USER_AGENT];
3272 19029 : if (newval == NULL)
3273 : {
3274 0 : return JB_ERR_OK;
3275 : }
3276 :
3277 19029 : freez(*header);
3278 19029 : *header = strdup("User-Agent: ");
3279 19029 : string_append(header, newval);
3280 :
3281 19029 : log_error(LOG_LEVEL_HEADER, "Modified: %s", *header);
3282 :
3283 19029 : return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
3284 : }
3285 :
3286 :
3287 : /*********************************************************************
3288 : *
3289 : * Function : client_ua
3290 : *
3291 : * Description : Handle "ua-" headers properly. Called from `sed'.
3292 : *
3293 : * Parameters :
3294 : * 1 : csp = Current client state (buffers, headers, etc...)
3295 : * 2 : header = On input, pointer to header to modify.
3296 : * On output, pointer to the modified header, or NULL
3297 : * to remove the header. This function frees the
3298 : * original string if necessary.
3299 : *
3300 : * Returns : JB_ERR_OK on success, or
3301 : * JB_ERR_MEMORY on out-of-memory error.
3302 : *
3303 : *********************************************************************/
3304 50 : static jb_err client_ua(struct client_state *csp, char **header)
3305 : {
3306 50 : if ((csp->action->flags & ACTION_HIDE_USER_AGENT) != 0)
3307 : {
3308 36 : log_error(LOG_LEVEL_HEADER, "crunched User-Agent!");
3309 36 : freez(*header);
3310 : }
3311 :
3312 50 : return JB_ERR_OK;
3313 : }
3314 :
3315 :
3316 : /*********************************************************************
3317 : *
3318 : * Function : client_from
3319 : *
3320 : * Description : Handle the "from" config setting properly.
3321 : * Called from `sed'.
3322 : *
3323 : * Parameters :
3324 : * 1 : csp = Current client state (buffers, headers, etc...)
3325 : * 2 : header = On input, pointer to header to modify.
3326 : * On output, pointer to the modified header, or NULL
3327 : * to remove the header. This function frees the
3328 : * original string if necessary.
3329 : *
3330 : * Returns : JB_ERR_OK on success, or
3331 : * JB_ERR_MEMORY on out-of-memory error.
3332 : *
3333 : *********************************************************************/
3334 327 : static jb_err client_from(struct client_state *csp, char **header)
3335 : {
3336 : const char *newval;
3337 :
3338 327 : if ((csp->action->flags & ACTION_HIDE_FROM) == 0)
3339 : {
3340 40 : return JB_ERR_OK;
3341 : }
3342 :
3343 287 : freez(*header);
3344 :
3345 287 : newval = csp->action->string[ACTION_STRING_FROM];
3346 :
3347 : /*
3348 : * Are we blocking the e-mail address?
3349 : */
3350 287 : if ((newval == NULL) || (0 == strcmpic(newval, "block")))
3351 : {
3352 0 : log_error(LOG_LEVEL_HEADER, "crunched From!");
3353 0 : return JB_ERR_OK;
3354 : }
3355 :
3356 287 : log_error(LOG_LEVEL_HEADER, " modified");
3357 :
3358 287 : *header = strdup("From: ");
3359 287 : string_append(header, newval);
3360 :
3361 287 : return (*header == NULL) ? JB_ERR_MEMORY : JB_ERR_OK;
3362 : }
3363 :
3364 :
3365 : /*********************************************************************
3366 : *
3367 : * Function : client_send_cookie
3368 : *
3369 : * Description : Crunches the "cookie" header if necessary.
3370 : * Called from `sed'.
3371 : *
3372 : * XXX: Stupid name, doesn't send squat.
3373 : *
3374 : * Parameters :
3375 : * 1 : csp = Current client state (buffers, headers, etc...)
3376 : * 2 : header = On input, pointer to header to modify.
3377 : * On output, pointer to the modified header, or NULL
3378 : * to remove the header. This function frees the
3379 : * original string if necessary.
3380 : *
3381 : * Returns : JB_ERR_OK on success, or
3382 : * JB_ERR_MEMORY on out-of-memory error.
3383 : *
3384 : *********************************************************************/
3385 299 : static jb_err client_send_cookie(struct client_state *csp, char **header)
3386 : {
3387 299 : if (csp->action->flags & ACTION_CRUNCH_OUTGOING_COOKIES)
3388 : {
3389 0 : log_error(LOG_LEVEL_HEADER, "Crunched outgoing cookie: %s", *header);
3390 0 : freez(*header);
3391 : }
3392 :
3393 299 : return JB_ERR_OK;
3394 : }
3395 :
3396 :
3397 : /*********************************************************************
3398 : *
3399 : * Function : client_x_forwarded
3400 : *
3401 : * Description : Handle the "x-forwarded-for" config setting properly,
3402 : * also used in the add_client_headers list. Called from `sed'.
3403 : *
3404 : * Parameters :
3405 : * 1 : csp = Current client state (buffers, headers, etc...)
3406 : * 2 : header = On input, pointer to header to modify.
3407 : * On output, pointer to the modified header, or NULL
3408 : * to remove the header. This function frees the
3409 : * original string if necessary.
3410 : *
3411 : * Returns : JB_ERR_OK on success, or
3412 : * JB_ERR_MEMORY on out-of-memory error.
3413 : *
3414 : *********************************************************************/
3415 2547 : jb_err client_x_forwarded(struct client_state *csp, char **header)
3416 : {
3417 2547 : if (0 != (csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR))
3418 : {
3419 2348 : const char *parameter = csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR];
3420 :
3421 2348 : if (0 == strcmpic(parameter, "block"))
3422 : {
3423 0 : freez(*header);
3424 0 : log_error(LOG_LEVEL_HEADER, "crunched x-forwarded-for!");
3425 : }
3426 2348 : else if (0 == strcmpic(parameter, "add"))
3427 : {
3428 2348 : string_append(header, ", ");
3429 2348 : string_append(header, csp->ip_addr_str);
3430 :
3431 2348 : if (*header == NULL)
3432 : {
3433 0 : return JB_ERR_MEMORY;
3434 : }
3435 2348 : log_error(LOG_LEVEL_HEADER,
3436 : "Appended client IP address to %s", *header);
3437 2348 : csp->flags |= CSP_FLAG_X_FORWARDED_FOR_APPENDED;
3438 : }
3439 : else
3440 : {
3441 0 : log_error(LOG_LEVEL_FATAL,
3442 : "Invalid change-x-forwarded-for parameter: '%s'", parameter);
3443 : }
3444 : }
3445 :
3446 2547 : return JB_ERR_OK;
3447 : }
3448 :
3449 :
3450 : /*********************************************************************
3451 : *
3452 : * Function : client_max_forwards
3453 : *
3454 : * Description : If the HTTP method is OPTIONS or TRACE, subtract one
3455 : * from the value of the Max-Forwards header field.
3456 : *
3457 : * Parameters :
3458 : * 1 : csp = Current client state (buffers, headers, etc...)
3459 : * 2 : header = On input, pointer to header to modify.
3460 : * On output, pointer to the modified header, or NULL
3461 : * to remove the header. This function frees the
3462 : * original string if necessary.
3463 : *
3464 : * Returns : JB_ERR_OK on success, or
3465 : * JB_ERR_MEMORY on out-of-memory error.
3466 : *
3467 : *********************************************************************/
3468 2237 : static jb_err client_max_forwards(struct client_state *csp, char **header)
3469 : {
3470 : int max_forwards;
3471 :
3472 3517 : if ((0 == strcmpic(csp->http->gpc, "trace")) ||
3473 1280 : (0 == strcmpic(csp->http->gpc, "options")))
3474 : {
3475 2111 : assert(*(*header+12) == ':');
3476 2111 : if (1 == sscanf(*header+12, ": %d", &max_forwards))
3477 : {
3478 1999 : if (max_forwards > 0)
3479 : {
3480 155 : snprintf(*header, strlen(*header)+1, "Max-Forwards: %d", --max_forwards);
3481 155 : log_error(LOG_LEVEL_HEADER,
3482 : "Max-Forwards value for %s request reduced to %d.",
3483 : csp->http->gpc, max_forwards);
3484 : }
3485 1844 : else if (max_forwards < 0)
3486 : {
3487 312 : log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
3488 312 : freez(*header);
3489 : }
3490 : }
3491 : else
3492 : {
3493 112 : log_error(LOG_LEVEL_ERROR, "Crunching invalid header: %s", *header);
3494 112 : freez(*header);
3495 : }
3496 : }
3497 :
3498 2237 : return JB_ERR_OK;
3499 : }
3500 :
3501 :
3502 : /*********************************************************************
3503 : *
3504 : * Function : client_host
3505 : *
3506 : * Description : If the request URI did not contain host and
3507 : * port information, parse and evaluate the Host
3508 : * header field.
3509 : *
3510 : * Parameters :
3511 : * 1 : csp = Current client state (buffers, headers, etc...)
3512 : * 2 : header = On input, pointer to header to modify.
3513 : * On output, pointer to the modified header, or NULL
3514 : * to remove the header. This function frees the
3515 : * original string if necessary.
3516 : *
3517 : * Returns : JB_ERR_OK on success, or
3518 : * JB_ERR_MEMORY on out-of-memory error.
3519 : *
3520 : *********************************************************************/
3521 64379 : static jb_err client_host(struct client_state *csp, char **header)
3522 : {
3523 : char *p, *q;
3524 :
3525 64379 : if (strlen(*header) < 7)
3526 : {
3527 1695 : log_error(LOG_LEVEL_HEADER, "Removing empty Host header");
3528 1695 : freez(*header);
3529 1695 : return JB_ERR_OK;
3530 : }
3531 :
3532 62684 : if (!csp->http->hostport || (*csp->http->hostport == '*') ||
3533 62258 : *csp->http->hostport == ' ' || *csp->http->hostport == '\0')
3534 : {
3535 :
3536 989 : p = strdup_or_die((*header)+6);
3537 989 : chomp(p);
3538 989 : q = strdup_or_die(p);
3539 :
3540 989 : freez(csp->http->hostport);
3541 989 : csp->http->hostport = p;
3542 989 : freez(csp->http->host);
3543 989 : csp->http->host = q;
3544 989 : q = strchr(csp->http->host, ':');
3545 989 : if (q != NULL)
3546 : {
3547 : /* Terminate hostname and evaluate port string */
3548 296 : *q++ = '\0';
3549 296 : csp->http->port = atoi(q);
3550 : }
3551 : else
3552 : {
3553 693 : csp->http->port = csp->http->ssl ? 443 : 80;
3554 : }
3555 :
3556 989 : log_error(LOG_LEVEL_HEADER, "New host and port from Host field: %s = %s:%d",
3557 : csp->http->hostport, csp->http->host, csp->http->port);
3558 : }
3559 :
3560 : /* Signal client_host_adder() to return right away */
3561 62684 : csp->flags |= CSP_FLAG_HOST_HEADER_IS_SET;
3562 :
3563 62684 : return JB_ERR_OK;
3564 : }
3565 :
3566 :
3567 : /*********************************************************************
3568 : *
3569 : * Function : client_if_modified_since
3570 : *
3571 : * Description : Remove or modify the If-Modified-Since header.
3572 : *
3573 : * Parameters :
3574 : * 1 : csp = Current client state (buffers, headers, etc...)
3575 : * 2 : header = On input, pointer to header to modify.
3576 : * On output, pointer to the modified header, or NULL
3577 : * to remove the header. This function frees the
3578 : * original string if necessary.
3579 : *
3580 : * Returns : JB_ERR_OK on success, or
3581 : * JB_ERR_MEMORY on out-of-memory error.
3582 : *
3583 : *********************************************************************/
3584 918 : static jb_err client_if_modified_since(struct client_state *csp, char **header)
3585 : {
3586 : char newheader[50];
3587 : struct tm gmt;
3588 918 : struct tm *timeptr = NULL;
3589 918 : time_t tm = 0;
3590 : const char *newval;
3591 : char * endptr;
3592 :
3593 918 : if (0 == strcmpic(*header, "If-Modified-Since: Wed, 08 Jun 1955 12:00:00 GMT"))
3594 : {
3595 : /*
3596 : * The client got an error message because of a temporary problem,
3597 : * the problem is gone and the client now tries to revalidate our
3598 : * error message on the real server. The revalidation would always
3599 : * end with the transmission of the whole document and there is
3600 : * no need to expose the bogus If-Modified-Since header.
3601 : */
3602 0 : log_error(LOG_LEVEL_HEADER, "Crunching useless If-Modified-Since header.");
3603 0 : freez(*header);
3604 : }
3605 918 : else if (csp->action->flags & ACTION_HIDE_IF_MODIFIED_SINCE)
3606 : {
3607 702 : newval = csp->action->string[ACTION_STRING_IF_MODIFIED_SINCE];
3608 :
3609 702 : if ((0 == strcmpic(newval, "block")))
3610 : {
3611 0 : log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3612 0 : freez(*header);
3613 : }
3614 : else /* add random value */
3615 : {
3616 702 : if (JB_ERR_OK != parse_time_header(*header, &tm))
3617 : {
3618 550 : log_error(LOG_LEVEL_HEADER,
3619 : "Couldn't parse time in %s (crunching!)", *header);
3620 550 : freez(*header);
3621 : }
3622 : else
3623 : {
3624 : long int hours, minutes, seconds;
3625 152 : long int rtime = strtol(newval, &endptr, 0);
3626 152 : const int negative_range = (rtime < 0);
3627 :
3628 152 : if (rtime)
3629 : {
3630 304 : log_error(LOG_LEVEL_HEADER, "Randomizing: %s (random range: %ld minut%s)",
3631 152 : *header, rtime, (rtime == 1 || rtime == -1) ? "e": "es");
3632 152 : if (negative_range)
3633 : {
3634 152 : rtime *= -1;
3635 : }
3636 152 : rtime *= 60;
3637 152 : rtime = pick_from_range(rtime);
3638 : }
3639 : else
3640 : {
3641 0 : log_error(LOG_LEVEL_ERROR,
3642 : "Random range is 0. Assuming time transformation test.");
3643 : }
3644 152 : tm += rtime * (negative_range ? -1 : 1);
3645 152 : timeptr = privoxy_gmtime_r(&tm, &gmt);
3646 152 : if ((NULL == timeptr) || !strftime(newheader,
3647 : sizeof(newheader), "%a, %d %b %Y %H:%M:%S GMT", timeptr))
3648 : {
3649 0 : log_error(LOG_LEVEL_ERROR,
3650 : "Randomizing '%s' failed. Crunching the header without replacement.",
3651 : *header);
3652 0 : freez(*header);
3653 0 : return JB_ERR_OK;
3654 : }
3655 152 : freez(*header);
3656 152 : *header = strdup("If-Modified-Since: ");
3657 152 : string_append(header, newheader);
3658 :
3659 152 : if (*header == NULL)
3660 : {
3661 0 : log_error(LOG_LEVEL_HEADER, "Insufficient memory, header crunched without replacement.");
3662 0 : return JB_ERR_MEMORY;
3663 : }
3664 :
3665 152 : hours = rtime / 3600;
3666 152 : minutes = rtime / 60 % 60;
3667 152 : seconds = rtime % 60;
3668 :
3669 152 : log_error(LOG_LEVEL_HEADER,
3670 : "Randomized: %s (%s %ld hou%s %ld minut%s %ld second%s",
3671 : *header, (negative_range) ? "subtracted" : "added", hours,
3672 : (hours == 1) ? "r" : "rs", minutes, (minutes == 1) ? "e" : "es",
3673 : seconds, (seconds == 1) ? ")" : "s)");
3674 : }
3675 : }
3676 : }
3677 :
3678 918 : return JB_ERR_OK;
3679 : }
3680 :
3681 :
3682 : /*********************************************************************
3683 : *
3684 : * Function : client_if_none_match
3685 : *
3686 : * Description : Remove the If-None-Match header.
3687 : *
3688 : * Parameters :
3689 : * 1 : csp = Current client state (buffers, headers, etc...)
3690 : * 2 : header = On input, pointer to header to modify.
3691 : * On output, pointer to the modified header, or NULL
3692 : * to remove the header. This function frees the
3693 : * original string if necessary.
3694 : *
3695 : * Returns : JB_ERR_OK on success, or
3696 : * JB_ERR_MEMORY on out-of-memory error.
3697 : *
3698 : *********************************************************************/
3699 359 : static jb_err client_if_none_match(struct client_state *csp, char **header)
3700 : {
3701 359 : if (csp->action->flags & ACTION_CRUNCH_IF_NONE_MATCH)
3702 : {
3703 347 : log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3704 347 : freez(*header);
3705 : }
3706 :
3707 359 : return JB_ERR_OK;
3708 : }
3709 :
3710 :
3711 : /*********************************************************************
3712 : *
3713 : * Function : client_x_filter
3714 : *
3715 : * Description : Disables filtering if the client set "X-Filter: No".
3716 : * Called from `sed'.
3717 : *
3718 : * Parameters :
3719 : * 1 : csp = Current client state (buffers, headers, etc...)
3720 : * 2 : header = On input, pointer to header to modify.
3721 : * On output, pointer to the modified header, or NULL
3722 : * to remove the header. This function frees the
3723 : * original string if necessary.
3724 : *
3725 : * Returns : JB_ERR_OK on success
3726 : *
3727 : *********************************************************************/
3728 803 : jb_err client_x_filter(struct client_state *csp, char **header)
3729 : {
3730 803 : if (0 == strcmpic(*header, "X-Filter: No"))
3731 : {
3732 26 : if (!(csp->config->feature_flags & RUNTIME_FEATURE_HTTP_TOGGLE))
3733 : {
3734 0 : log_error(LOG_LEVEL_INFO, "Ignored the client's request to fetch without filtering.");
3735 : }
3736 : else
3737 : {
3738 26 : if (csp->action->flags & ACTION_FORCE_TEXT_MODE)
3739 : {
3740 0 : log_error(LOG_LEVEL_HEADER,
3741 : "force-text-mode overruled the client's request to fetch without filtering!");
3742 : }
3743 : else
3744 : {
3745 26 : csp->content_type = CT_TABOO; /* XXX: This hack shouldn't be necessary */
3746 26 : csp->flags |= CSP_FLAG_NO_FILTERING;
3747 26 : log_error(LOG_LEVEL_HEADER, "Accepted the client's request to fetch without filtering.");
3748 : }
3749 26 : log_error(LOG_LEVEL_HEADER, "Crunching %s", *header);
3750 26 : freez(*header);
3751 : }
3752 : }
3753 803 : return JB_ERR_OK;
3754 : }
3755 :
3756 :
3757 : /*********************************************************************
3758 : *
3759 : * Function : client_range
3760 : *
3761 : * Description : Removes Range, Request-Range and If-Range headers if
3762 : * content filtering is enabled and the range doesn't
3763 : * start at byte 0.
3764 : *
3765 : * If the client's version of the document has been
3766 : * altered by Privoxy, the server could interpret the
3767 : * range differently than the client intended in which
3768 : * case the user could end up with corrupted content.
3769 : *
3770 : * If the range starts at byte 0 this isn't an issue
3771 : * so the header can pass. Partial requests like this
3772 : * are used to render preview images for videos without
3773 : * downloading the whole video.
3774 : *
3775 : * While HTTP doesn't require that range requests are
3776 : * honoured and the client could simply abort the download
3777 : * after receiving a sufficient amount of data, various
3778 : * clients don't handle complete responses to range
3779 : * requests gracefully and emit misleading error messages
3780 : * instead.
3781 : *
3782 : * Parameters :
3783 : * 1 : csp = Current client state (buffers, headers, etc...)
3784 : * 2 : header = On input, pointer to header to modify.
3785 : * On output, pointer to the modified header, or NULL
3786 : * to remove the header. This function frees the
3787 : * original string if necessary.
3788 : *
3789 : * Returns : JB_ERR_OK
3790 : *
3791 : *********************************************************************/
3792 30 : static jb_err client_range(struct client_state *csp, char **header)
3793 : {
3794 30 : if (content_filters_enabled(csp->action)
3795 13 : && (0 != strncmpic(strstr(*header, ":"), ": bytes=0-", 10)))
3796 : {
3797 13 : log_error(LOG_LEVEL_HEADER, "Content filtering is enabled."
3798 : " Crunching: \'%s\' to prevent range-mismatch problems.", *header);
3799 13 : freez(*header);
3800 : }
3801 :
3802 30 : return JB_ERR_OK;
3803 : }
3804 :
3805 : /* the following functions add headers directly to the header list */
3806 :
3807 : /*********************************************************************
3808 : *
3809 : * Function : client_host_adder
3810 : *
3811 : * Description : Adds the Host: header field if it is missing.
3812 : * Called from `sed'.
3813 : *
3814 : * Parameters :
3815 : * 1 : csp = Current client state (buffers, headers, etc...)
3816 : *
3817 : * Returns : JB_ERR_OK on success, or
3818 : * JB_ERR_MEMORY on out-of-memory error.
3819 : *
3820 : *********************************************************************/
3821 33272 : static jb_err client_host_adder(struct client_state *csp)
3822 : {
3823 : char *p;
3824 : jb_err err;
3825 :
3826 33272 : if (csp->flags & CSP_FLAG_HOST_HEADER_IS_SET)
3827 : {
3828 : /* Header already set by the client, nothing to do. */
3829 31789 : return JB_ERR_OK;
3830 : }
3831 :
3832 1483 : if (!csp->http->hostport || !*(csp->http->hostport))
3833 : {
3834 3 : log_error(LOG_LEVEL_ERROR, "Destination host unknown.");
3835 3 : return JB_ERR_PARSE;
3836 : }
3837 :
3838 : /*
3839 : * remove 'user:pass@' from 'proto://user:pass@host'
3840 : */
3841 1480 : if ((p = strchr( csp->http->hostport, '@')) != NULL)
3842 : {
3843 3 : p++;
3844 : }
3845 : else
3846 : {
3847 1477 : p = csp->http->hostport;
3848 : }
3849 :
3850 : /* XXX: Just add it, we already made sure that it will be unique */
3851 1480 : log_error(LOG_LEVEL_HEADER, "addh-unique: Host: %s", p);
3852 1480 : err = enlist_unique_header(csp->headers, "Host", p);
3853 1480 : return err;
3854 :
3855 : }
3856 :
3857 :
3858 : /*********************************************************************
3859 : *
3860 : * Function : client_xtra_adder
3861 : *
3862 : * Description : Used in the add_client_headers list. Called from `sed'.
3863 : *
3864 : * Parameters :
3865 : * 1 : csp = Current client state (buffers, headers, etc...)
3866 : *
3867 : * Returns : JB_ERR_OK on success, or
3868 : * JB_ERR_MEMORY on out-of-memory error.
3869 : *
3870 : *********************************************************************/
3871 33269 : static jb_err client_xtra_adder(struct client_state *csp)
3872 : {
3873 : struct list_entry *lst;
3874 : jb_err err;
3875 :
3876 33269 : for (lst = csp->action->multi[ACTION_MULTI_ADD_HEADER]->first;
3877 0 : lst ; lst = lst->next)
3878 : {
3879 0 : log_error(LOG_LEVEL_HEADER, "addh: %s", lst->str);
3880 0 : err = enlist(csp->headers, lst->str);
3881 0 : if (err)
3882 : {
3883 0 : return err;
3884 : }
3885 :
3886 : }
3887 :
3888 33269 : return JB_ERR_OK;
3889 : }
3890 :
3891 :
3892 : /*********************************************************************
3893 : *
3894 : * Function : client_x_forwarded_for_adder
3895 : *
3896 : * Description : Used in the add_client_headers list. Called from `sed'.
3897 : *
3898 : * Parameters :
3899 : * 1 : csp = Current client state (buffers, headers, etc...)
3900 : *
3901 : * Returns : JB_ERR_OK on success, or
3902 : * JB_ERR_MEMORY on out-of-memory error.
3903 : *
3904 : *********************************************************************/
3905 33269 : static jb_err client_x_forwarded_for_adder(struct client_state *csp)
3906 : {
3907 33269 : char *header = NULL;
3908 : jb_err err;
3909 :
3910 65351 : if (!((csp->action->flags & ACTION_CHANGE_X_FORWARDED_FOR)
3911 32082 : && (0 == strcmpic(csp->action->string[ACTION_STRING_CHANGE_X_FORWARDED_FOR], "add")))
3912 32082 : || (csp->flags & CSP_FLAG_X_FORWARDED_FOR_APPENDED))
3913 : {
3914 : /*
3915 : * If we aren't adding X-Forwarded-For headers,
3916 : * or we already appended an existing X-Forwarded-For
3917 : * header, there's nothing left to do here.
3918 : */
3919 3153 : return JB_ERR_OK;
3920 : }
3921 :
3922 30116 : header = strdup("X-Forwarded-For: ");
3923 30116 : string_append(&header, csp->ip_addr_str);
3924 :
3925 30116 : if (header == NULL)
3926 : {
3927 0 : return JB_ERR_MEMORY;
3928 : }
3929 :
3930 30116 : log_error(LOG_LEVEL_HEADER, "addh: %s", header);
3931 30116 : err = enlist(csp->headers, header);
3932 30116 : freez(header);
3933 :
3934 30116 : return err;
3935 : }
3936 :
3937 :
3938 : /*********************************************************************
3939 : *
3940 : * Function : server_connection_adder
3941 : *
3942 : * Description : Adds an appropriate "Connection:" header to csp->headers
3943 : * unless the header was already present. Called from `sed'.
3944 : *
3945 : * Parameters :
3946 : * 1 : csp = Current client state (buffers, headers, etc...)
3947 : *
3948 : * Returns : JB_ERR_OK on success, or
3949 : * JB_ERR_MEMORY on out-of-memory error.
3950 : *
3951 : *********************************************************************/
3952 5984 : static jb_err server_connection_adder(struct client_state *csp)
3953 : {
3954 5984 : const unsigned int flags = csp->flags;
3955 5984 : const char *response_status_line = csp->headers->first->str;
3956 : static const char connection_close[] = "Connection: close";
3957 :
3958 5984 : if ((flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
3959 5984 : && (flags & CSP_FLAG_SERVER_CONNECTION_HEADER_SET))
3960 : {
3961 888 : return JB_ERR_OK;
3962 : }
3963 :
3964 : /*
3965 : * XXX: if we downgraded the response, this check will fail.
3966 : */
3967 5096 : if ((csp->config->feature_flags &
3968 : RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
3969 5096 : && (NULL != response_status_line)
3970 5095 : && !strncmpic(response_status_line, "HTTP/1.1", 8)
3971 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3972 4666 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
3973 : #endif
3974 : )
3975 : {
3976 4662 : log_error(LOG_LEVEL_HEADER, "A HTTP/1.1 response "
3977 : "without Connection header implies keep-alive.");
3978 4662 : csp->flags |= CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE;
3979 4662 : return JB_ERR_OK;
3980 : }
3981 :
3982 434 : log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
3983 :
3984 434 : return enlist(csp->headers, connection_close);
3985 : }
3986 :
3987 :
3988 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3989 : /*********************************************************************
3990 : *
3991 : * Function : server_proxy_connection_adder
3992 : *
3993 : * Description : Adds a "Proxy-Connection: keep-alive" header to
3994 : * csp->headers when appropriate.
3995 : *
3996 : * Parameters :
3997 : * 1 : csp = Current client state (buffers, headers, etc...)
3998 : *
3999 : * Returns : JB_ERR_OK on success, or
4000 : * JB_ERR_MEMORY on out-of-memory error.
4001 : *
4002 : *********************************************************************/
4003 5984 : static jb_err server_proxy_connection_adder(struct client_state *csp)
4004 : {
4005 : static const char proxy_connection_header[] = "Proxy-Connection: keep-alive";
4006 5984 : jb_err err = JB_ERR_OK;
4007 :
4008 5984 : if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4009 5853 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4010 5833 : && !(csp->flags & CSP_FLAG_SERVER_PROXY_CONNECTION_HEADER_SET)
4011 5650 : && ((csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET)
4012 5525 : || (csp->flags & CSP_FLAG_CHUNKED))
4013 : #ifdef FEATURE_HTTPS_INSPECTION
4014 2672 : && !client_use_ssl(csp)
4015 2641 : && !csp->http->ssl
4016 : #endif
4017 : )
4018 : {
4019 2641 : log_error(LOG_LEVEL_HEADER, "Adding: %s", proxy_connection_header);
4020 2641 : err = enlist(csp->headers, proxy_connection_header);
4021 : }
4022 :
4023 5984 : return err;
4024 : }
4025 : #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
4026 :
4027 :
4028 : /*********************************************************************
4029 : *
4030 : * Function : client_connection_header_adder
4031 : *
4032 : * Description : Adds a proper "Connection:" header to csp->headers
4033 : * unless the header was already present or it's a
4034 : * CONNECT request. Called from `sed'.
4035 : *
4036 : * Parameters :
4037 : * 1 : csp = Current client state (buffers, headers, etc...)
4038 : *
4039 : * Returns : JB_ERR_OK on success, or
4040 : * JB_ERR_MEMORY on out-of-memory error.
4041 : *
4042 : *********************************************************************/
4043 33269 : static jb_err client_connection_header_adder(struct client_state *csp)
4044 : {
4045 : static const char connection_close[] = "Connection: close";
4046 :
4047 33269 : if (!(csp->flags & CSP_FLAG_CLIENT_HEADER_PARSING_DONE)
4048 33269 : && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_HEADER_SET))
4049 : {
4050 7374 : return JB_ERR_OK;
4051 : }
4052 :
4053 : /*
4054 : * In case of CONNECT requests "Connection: close" is implied,
4055 : * but actually setting the header has been reported to cause
4056 : * problems with some forwarding proxies that close the
4057 : * connection prematurely.
4058 : */
4059 25895 : if (csp->http->ssl != 0)
4060 : {
4061 2094 : return JB_ERR_OK;
4062 : }
4063 :
4064 : #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4065 23801 : if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
4066 23801 : && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4067 23777 : && !strcmpic(csp->http->version, "HTTP/1.1"))
4068 : {
4069 23626 : csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
4070 23626 : return JB_ERR_OK;
4071 : }
4072 : #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
4073 :
4074 175 : log_error(LOG_LEVEL_HEADER, "Adding: %s", connection_close);
4075 :
4076 175 : return enlist(csp->headers, connection_close);
4077 : }
4078 :
4079 :
4080 : /*********************************************************************
4081 : *
4082 : * Function : server_http
4083 : *
4084 : * Description : - Save the HTTP Status into csp->http->status
4085 : * - Set CT_TABOO to prevent filtering if the answer
4086 : * is a partial range (HTTP status 206)
4087 : * - Rewrite HTTP/1.1 answers to HTTP/1.0 if +downgrade
4088 : * action applies.
4089 : * - Normalize the HTTP-version.
4090 : *
4091 : * Parameters :
4092 : * 1 : csp = Current client state (buffers, headers, etc...)
4093 : * 2 : header = On input, pointer to header to modify.
4094 : * On output, pointer to the modified header, or NULL
4095 : * to remove the header. This function frees the
4096 : * original string if necessary.
4097 : *
4098 : * Returns : JB_ERR_OK on success, or
4099 : * JB_ERR_PARSE on fatal parse errors.
4100 : *
4101 : *********************************************************************/
4102 6950 : static jb_err server_http(struct client_state *csp, char **header)
4103 : {
4104 6950 : char *reason_phrase = NULL;
4105 : char *new_response_line;
4106 : char *p;
4107 : size_t length;
4108 : unsigned int major_version;
4109 : unsigned int minor_version;
4110 :
4111 : /* Get the reason phrase which start after the second whitespace */
4112 6950 : p = strchr(*header, ' ');
4113 6950 : if (NULL != p)
4114 : {
4115 6854 : p++;
4116 6854 : reason_phrase = strchr(p, ' ');
4117 : }
4118 :
4119 6950 : if (reason_phrase != NULL)
4120 : {
4121 6679 : reason_phrase++;
4122 : }
4123 : else
4124 : {
4125 271 : log_error(LOG_LEVEL_ERROR,
4126 : "Response line lacks reason phrase: %s", *header);
4127 271 : reason_phrase="";
4128 : }
4129 :
4130 6950 : if (3 != sscanf(*header, "HTTP/%u.%u %d", &major_version,
4131 : &minor_version, &(csp->http->status)))
4132 : {
4133 25 : log_error(LOG_LEVEL_ERROR,
4134 : "Failed to parse the response line: %s", *header);
4135 25 : return JB_ERR_PARSE;
4136 : }
4137 :
4138 6925 : if (csp->http->status == 101 ||
4139 6856 : csp->http->status == 206)
4140 : {
4141 107 : csp->content_type = CT_TABOO;
4142 : }
4143 :
4144 6925 : if (major_version != 1 || (minor_version != 0 && minor_version != 1))
4145 : {
4146 : /*
4147 : * According to RFC 7230 2.6 intermediaries MUST send
4148 : * their own HTTP-version in forwarded messages.
4149 : */
4150 275 : log_error(LOG_LEVEL_ERROR,
4151 : "Unsupported HTTP version. Downgrading to 1.1.");
4152 275 : major_version = 1;
4153 275 : minor_version = 1;
4154 : }
4155 :
4156 6925 : if (((csp->action->flags & ACTION_DOWNGRADE) != 0) && (minor_version == 1))
4157 : {
4158 285 : log_error(LOG_LEVEL_HEADER, "Downgrading answer to HTTP/1.0");
4159 285 : minor_version = 0;
4160 : }
4161 :
4162 : /* Rebuild response line. */
4163 6925 : length = sizeof("HTTP/1.1 200 ") + strlen(reason_phrase) + 1;
4164 6925 : new_response_line = malloc_or_die(length);
4165 :
4166 6925 : snprintf(new_response_line, length, "HTTP/%u.%u %d %s",
4167 : major_version, minor_version, csp->http->status, reason_phrase);
4168 :
4169 6925 : if (0 != strcmp(*header, new_response_line))
4170 : {
4171 815 : log_error(LOG_LEVEL_HEADER, "Response line '%s' changed to '%s'",
4172 : *header, new_response_line);
4173 : }
4174 :
4175 6925 : freez(*header);
4176 6925 : *header = new_response_line;
4177 :
4178 6925 : return JB_ERR_OK;
4179 : }
4180 :
4181 : /*********************************************************************
4182 : *
4183 : * Function : add_cooky_expiry_date
4184 : *
4185 : * Description : Adds a cookie expiry date to a string.
4186 : *
4187 : * Parameters :
4188 : * 1 : cookie = On input, pointer to cookie to modify.
4189 : * On output, pointer to the modified header.
4190 : * The original string is freed.
4191 : * 2 : lifetime = Seconds the cookie should be valid
4192 : *
4193 : * Returns : N/A
4194 : *
4195 : *********************************************************************/
4196 487 : static void add_cookie_expiry_date(char **cookie, time_t lifetime)
4197 : {
4198 : char tmp[50];
4199 487 : struct tm *timeptr = NULL;
4200 487 : time_t expiry_date = time(NULL) + lifetime;
4201 : struct tm gmt;
4202 :
4203 487 : timeptr = privoxy_gmtime_r(&expiry_date, &gmt);
4204 487 : if (NULL == timeptr)
4205 : {
4206 0 : log_error(LOG_LEVEL_FATAL,
4207 : "Failed to get the time in add_cooky_expiry_date()");
4208 : }
4209 487 : strftime(tmp, sizeof(tmp), "; expires=%a, %d-%b-%Y %H:%M:%S GMT", timeptr);
4210 487 : if (JB_ERR_OK != string_append(cookie, tmp))
4211 : {
4212 0 : log_error(LOG_LEVEL_FATAL, "Out of memory in add_cooky_expiry()");
4213 : }
4214 487 : }
4215 :
4216 :
4217 : /*********************************************************************
4218 : *
4219 : * Function : server_set_cookie
4220 : *
4221 : * Description : Handle the server "cookie" header properly.
4222 : * Crunch, accept or rewrite it to a session cookie.
4223 : * Called from `sed'.
4224 : *
4225 : * Parameters :
4226 : * 1 : csp = Current client state (buffers, headers, etc...)
4227 : * 2 : header = On input, pointer to header to modify.
4228 : * On output, pointer to the modified header, or NULL
4229 : * to remove the header. This function frees the
4230 : * original string if necessary.
4231 : *
4232 : * Returns : JB_ERR_OK on success, or
4233 : * JB_ERR_MEMORY on out-of-memory error.
4234 : *
4235 : *********************************************************************/
4236 579 : static jb_err server_set_cookie(struct client_state *csp, char **header)
4237 : {
4238 579 : if ((csp->action->flags & ACTION_CRUNCH_INCOMING_COOKIES) != 0)
4239 : {
4240 0 : log_error(LOG_LEVEL_HEADER, "Crunching incoming cookie: %s", *header);
4241 0 : freez(*header);
4242 : }
4243 579 : else if ((0 != (csp->action->flags & ACTION_SESSION_COOKIES_ONLY))
4244 579 : || (0 != (csp->action->flags & ACTION_LIMIT_COOKIE_LIFETIME)))
4245 : {
4246 : time_t now;
4247 : time_t cookie_time;
4248 505 : long cookie_lifetime = 0;
4249 : enum
4250 : {
4251 : NO_EXPIRY_DATE_SPECIFIED,
4252 : EXPIRY_DATE_ACCEPTABLE,
4253 : EXPIRY_DATE_UNACCEPTABLE
4254 505 : } expiry_date_status = NO_EXPIRY_DATE_SPECIFIED;
4255 :
4256 : /* A variable to store the tag we're working on */
4257 : char *cur_tag;
4258 :
4259 : /* Skip "Set-Cookie:" (11 characters) in header */
4260 505 : cur_tag = *header + 11;
4261 :
4262 : /* skip whitespace between "Set-Cookie:" and value */
4263 830 : while (*cur_tag && privoxy_isspace(*cur_tag))
4264 : {
4265 325 : cur_tag++;
4266 : }
4267 :
4268 505 : time(&now);
4269 :
4270 505 : if ((csp->action->flags & ACTION_LIMIT_COOKIE_LIFETIME) != 0)
4271 : {
4272 505 : const char *param = csp->action->string[ACTION_STRING_LIMIT_COOKIE_LIFETIME];
4273 :
4274 505 : cookie_lifetime = strtol(param, NULL, 0);
4275 505 : if (cookie_lifetime < 0)
4276 : {
4277 0 : log_error(LOG_LEVEL_FATAL, "Invalid cookie lifetime limit: %s", param);
4278 : }
4279 505 : cookie_lifetime *= 60;
4280 : }
4281 :
4282 : /* Loop through each tag in the cookie */
4283 1402 : while (*cur_tag)
4284 : {
4285 : /* Find next tag */
4286 897 : char *next_tag = strchr(cur_tag, ';');
4287 897 : if (next_tag != NULL)
4288 : {
4289 : /* Skip the ';' character itself */
4290 530 : next_tag++;
4291 :
4292 : /* skip whitespace ";" and start of tag */
4293 987 : while (*next_tag && privoxy_isspace(*next_tag))
4294 : {
4295 457 : next_tag++;
4296 : }
4297 : }
4298 : else
4299 : {
4300 : /* "Next tag" is the end of the string */
4301 367 : next_tag = cur_tag + strlen(cur_tag);
4302 : }
4303 :
4304 : /*
4305 : * Check the expiration date to see
4306 : * if the cookie is still valid, if yes,
4307 : * rewrite it to a session cookie.
4308 : */
4309 897 : if ((strncmpic(cur_tag, "expires=", 8) == 0) && *(cur_tag + 8))
4310 138 : {
4311 138 : char *expiration_date = cur_tag + 8; /* Skip "[Ee]xpires=" */
4312 :
4313 138 : if ((expiration_date[0] == '"')
4314 19 : && (expiration_date[1] != '\0'))
4315 : {
4316 : /*
4317 : * Skip quotation mark. RFC 2109 10.1.2 seems to hint
4318 : * that the expiration date isn't supposed to be quoted,
4319 : * but some servers do it anyway.
4320 : */
4321 19 : expiration_date++;
4322 : }
4323 :
4324 : /* Did we detect the date properly? */
4325 138 : if (JB_ERR_OK != parse_header_time(expiration_date, &cookie_time))
4326 : {
4327 : /*
4328 : * Nope, treat it as if it was still valid.
4329 : *
4330 : * XXX: Should we remove the whole cookie instead?
4331 : */
4332 79 : log_error(LOG_LEVEL_ERROR,
4333 : "Can't parse \'%s\', send by %s. Unsupported time format?", cur_tag, csp->http->url);
4334 79 : string_move(cur_tag, next_tag);
4335 79 : expiry_date_status = EXPIRY_DATE_UNACCEPTABLE;
4336 : }
4337 : else
4338 : {
4339 : /*
4340 : * Yes. Check if the cookie is still valid.
4341 : *
4342 : * If the cookie is already expired it's probably
4343 : * a delete cookie and even if it isn't, the browser
4344 : * will discard it anyway.
4345 : */
4346 :
4347 : /*
4348 : * XXX: timegm() isn't available on some AmigaOS
4349 : * versions and our replacement doesn't work.
4350 : *
4351 : * Our options are to either:
4352 : *
4353 : * - disable session-cookies-only completely if timegm
4354 : * is missing,
4355 : *
4356 : * - to simply remove all expired tags, like it has
4357 : * been done until Privoxy 3.0.6 and to live with
4358 : * the consequence that it can cause login/logout
4359 : * problems on servers that don't validate their
4360 : * input properly, or
4361 : *
4362 : * - to replace it with mktime in which
4363 : * case there is a slight chance of valid cookies
4364 : * passing as already expired.
4365 : *
4366 : * This is the way it's currently done and it's not
4367 : * as bad as it sounds. If the missing GMT offset is
4368 : * enough to change the result of the expiration check
4369 : * the cookie will be only valid for a few hours
4370 : * anyway, which in many cases will be shorter
4371 : * than a browser session.
4372 : */
4373 59 : if (cookie_time < now)
4374 : {
4375 18 : log_error(LOG_LEVEL_HEADER,
4376 : "Cookie \'%s\' is already expired and can pass unmodified.", *header);
4377 : /* Just in case some clown sets more then one expiration date */
4378 18 : cur_tag = next_tag;
4379 18 : expiry_date_status = EXPIRY_DATE_ACCEPTABLE;
4380 : }
4381 41 : else if ((cookie_lifetime != 0) && (cookie_time < (now + cookie_lifetime)))
4382 : {
4383 0 : log_error(LOG_LEVEL_HEADER, "Cookie \'%s\' can pass unmodified. "
4384 : "Its lifetime is below the limit.", *header);
4385 : /* Just in case some clown sets more then one expiration date */
4386 0 : cur_tag = next_tag;
4387 0 : expiry_date_status = EXPIRY_DATE_ACCEPTABLE;
4388 : }
4389 : else
4390 : {
4391 : /*
4392 : * Still valid, delete expiration date by copying
4393 : * the rest of the string over it.
4394 : */
4395 41 : string_move(cur_tag, next_tag);
4396 :
4397 : /* That changed the header, need to issue a log message */
4398 41 : expiry_date_status = EXPIRY_DATE_UNACCEPTABLE;
4399 :
4400 : /*
4401 : * Note that the next tag has now been moved to *cur_tag,
4402 : * so we do not need to update the cur_tag pointer.
4403 : */
4404 : }
4405 : }
4406 :
4407 : }
4408 : else
4409 : {
4410 : /* Move on to next cookie tag */
4411 759 : cur_tag = next_tag;
4412 : }
4413 : }
4414 :
4415 505 : if (expiry_date_status != EXPIRY_DATE_ACCEPTABLE)
4416 : {
4417 487 : assert(NULL != *header);
4418 487 : if (cookie_lifetime != 0)
4419 : {
4420 487 : add_cookie_expiry_date(header, cookie_lifetime);
4421 487 : log_error(LOG_LEVEL_HEADER, "Cookie rewritten to: %s", *header);
4422 : }
4423 0 : else if (expiry_date_status != NO_EXPIRY_DATE_SPECIFIED)
4424 : {
4425 0 : log_error(LOG_LEVEL_HEADER,
4426 : "Cookie rewritten to a temporary one: %s", *header);
4427 : }
4428 : }
4429 : }
4430 :
4431 579 : return JB_ERR_OK;
4432 : }
4433 :
4434 :
4435 : #ifdef FEATURE_FORCE_LOAD
4436 : /*********************************************************************
4437 : *
4438 : * Function : strclean
4439 : *
4440 : * Description : In-Situ-Eliminate all occurrences of substring in
4441 : * string
4442 : *
4443 : * Parameters :
4444 : * 1 : string = string to clean
4445 : * 2 : substring = substring to eliminate
4446 : *
4447 : * Returns : Number of eliminations
4448 : *
4449 : *********************************************************************/
4450 11919 : int strclean(char *string, const char *substring)
4451 : {
4452 11919 : int hits = 0;
4453 : size_t len;
4454 : char *pos, *p;
4455 :
4456 11919 : len = strlen(substring);
4457 :
4458 12958 : while((pos = strstr(string, substring)) != NULL)
4459 : {
4460 1039 : p = pos + len;
4461 : do
4462 : {
4463 1039 : *(p - len) = *p;
4464 : }
4465 1039 : while (*p++ != '\0');
4466 :
4467 1039 : hits++;
4468 : }
4469 :
4470 11919 : return(hits);
4471 : }
4472 : #endif /* def FEATURE_FORCE_LOAD */
4473 :
4474 :
4475 : /*********************************************************************
4476 : *
4477 : * Function : parse_header_time
4478 : *
4479 : * Description : Parses time formats used in HTTP header strings
4480 : * to get the numerical respresentation.
4481 : *
4482 : * Parameters :
4483 : * 1 : header_time = HTTP header time as string.
4484 : * 2 : result = storage for header_time in seconds
4485 : *
4486 : * Returns : JB_ERR_OK if the time format was recognized, or
4487 : * JB_ERR_PARSE otherwise.
4488 : *
4489 : *********************************************************************/
4490 2902 : static jb_err parse_header_time(const char *header_time, time_t *result)
4491 : {
4492 : struct tm gmt;
4493 : /*
4494 : * Checking for two-digit years first in an
4495 : * attempt to work around GNU libc's strptime()
4496 : * reporting negative year values when using %Y.
4497 : */
4498 : static const char time_formats[][22] = {
4499 : /* Tue, 02-Jun-37 20:00:00 */
4500 : "%a, %d-%b-%y %H:%M:%S",
4501 : /* Tue, 02 Jun 2037 20:00:00 */
4502 : "%a, %d %b %Y %H:%M:%S",
4503 : /* Tue, 02-Jun-2037 20:00:00 */
4504 : "%a, %d-%b-%Y %H:%M:%S",
4505 : /* Tuesday, 02-Jun-2037 20:00:00 */
4506 : "%A, %d-%b-%Y %H:%M:%S",
4507 : /* Tuesday Jun 02 20:00:00 2037 */
4508 : "%A %b %d %H:%M:%S %Y"
4509 : };
4510 : unsigned int i;
4511 :
4512 13504 : for (i = 0; i < SZ(time_formats); i++)
4513 : {
4514 : /*
4515 : * Zero out gmt to prevent time zone offsets.
4516 : * Documented to be required for GNU libc.
4517 : */
4518 11579 : memset(&gmt, 0, sizeof(gmt));
4519 :
4520 11579 : if (NULL != strptime(header_time, time_formats[i], &gmt))
4521 : {
4522 : /* Sanity check for GNU libc. */
4523 1504 : if (gmt.tm_year < 0)
4524 : {
4525 527 : log_error(LOG_LEVEL_HEADER,
4526 : "Failed to parse '%s' using '%s'. Moving on.",
4527 527 : header_time, time_formats[i]);
4528 527 : continue;
4529 : }
4530 977 : *result = timegm(&gmt);
4531 :
4532 : #ifdef FEATURE_STRPTIME_SANITY_CHECKS
4533 : /*
4534 : * Verify that parsing the date recreated from the first
4535 : * parse operation gets the previous result. If it doesn't,
4536 : * either strptime() or strftime() are malfunctioning.
4537 : *
4538 : * We could string-compare the recreated date with the original
4539 : * header date, but this leads to false positives as strptime()
4540 : * may let %a accept all day formats while strftime() will only
4541 : * create one.
4542 : */
4543 : {
4544 : char recreated_date[100];
4545 : struct tm *tm;
4546 : struct tm storage;
4547 : time_t result2;
4548 :
4549 977 : tm = privoxy_gmtime_r(result, &storage);
4550 977 : if (!strftime(recreated_date, sizeof(recreated_date),
4551 977 : time_formats[i], tm))
4552 : {
4553 0 : log_error(LOG_LEVEL_ERROR, "Failed to recreate date '%s' with '%s'.",
4554 0 : header_time, time_formats[i]);
4555 0 : continue;
4556 : }
4557 977 : memset(&gmt, 0, sizeof(gmt));
4558 977 : if (NULL == strptime(recreated_date, time_formats[i], &gmt))
4559 : {
4560 0 : log_error(LOG_LEVEL_ERROR,
4561 : "Failed to parse '%s' generated with '%s' to recreate '%s'.",
4562 0 : recreated_date, time_formats[i], header_time);
4563 0 : continue;
4564 : }
4565 977 : result2 = timegm(&gmt);
4566 977 : if (*result != result2)
4567 : {
4568 0 : log_error(LOG_LEVEL_ERROR, "strftime() and strptime() disagree. "
4569 : "Format: '%s'. In: '%s', out: '%s'. %ld != %ld. Rejecting.",
4570 0 : time_formats[i], header_time, recreated_date, *result, result2);
4571 0 : continue;
4572 : }
4573 : }
4574 : #endif
4575 :
4576 977 : return JB_ERR_OK;
4577 : }
4578 : }
4579 :
4580 1925 : return JB_ERR_PARSE;
4581 :
4582 : }
4583 :
4584 : /*********************************************************************
4585 : *
4586 : * Function : parse_time_header
4587 : *
4588 : * Description : Parses the time in an HTTP time header to get
4589 : * the numerical respresentation.
4590 : *
4591 : * Parameters :
4592 : * 1 : header = HTTP header with a time value
4593 : * 2 : result = storage for header_time in seconds
4594 : *
4595 : * Returns : JB_ERR_OK if the time format was recognized, or
4596 : * JB_ERR_PARSE otherwise.
4597 : *
4598 : *********************************************************************/
4599 2764 : static jb_err parse_time_header(const char *header, time_t *result)
4600 : {
4601 : const char *header_time;
4602 :
4603 2764 : header_time = strchr(header, ':');
4604 :
4605 : /*
4606 : * Currently this can't happen as all callers are called
4607 : * through sed() which requires a header name followed by
4608 : * a colon.
4609 : */
4610 2764 : assert(header_time != NULL);
4611 :
4612 2764 : header_time++;
4613 2764 : if (*header_time == ' ')
4614 : {
4615 2627 : header_time++;
4616 : }
4617 :
4618 2764 : return parse_header_time(header_time, result);
4619 :
4620 : }
4621 :
4622 :
4623 : /*********************************************************************
4624 : *
4625 : * Function : get_destination_from_headers
4626 : *
4627 : * Description : Parse the "Host:" header to get the request's destination.
4628 : * Only needed if the client's request was forcefully
4629 : * redirected into Privoxy.
4630 : *
4631 : * Code mainly copied from client_host() which is currently
4632 : * run too late for this purpose.
4633 : *
4634 : * Parameters :
4635 : * 1 : headers = List of headers (one of them hopefully being
4636 : * the "Host:" header)
4637 : * 2 : http = storage for the result (host, port and hostport).
4638 : *
4639 : * Returns : JB_ERR_MEMORY (or terminates) in case of memory problems,
4640 : * JB_ERR_PARSE if the host header couldn't be found,
4641 : * JB_ERR_OK otherwise.
4642 : *
4643 : *********************************************************************/
4644 15190 : jb_err get_destination_from_headers(const struct list *headers, struct http_request *http)
4645 : {
4646 : char *q;
4647 : char *p;
4648 : char *host;
4649 :
4650 15190 : host = get_header_value(headers, "Host:");
4651 :
4652 15190 : if (NULL == host)
4653 : {
4654 20 : log_error(LOG_LEVEL_ERROR, "No \"Host:\" header found.");
4655 20 : return JB_ERR_PARSE;
4656 : }
4657 :
4658 15170 : p = string_tolower(host);
4659 15170 : if (p == NULL)
4660 : {
4661 0 : return JB_ERR_MEMORY;
4662 : }
4663 15170 : chomp(p);
4664 15170 : q = strdup_or_die(p);
4665 :
4666 15170 : freez(http->hostport);
4667 15170 : http->hostport = p;
4668 15170 : freez(http->host);
4669 15170 : http->host = q;
4670 15170 : q = strchr(http->host, ':');
4671 15170 : if (q != NULL)
4672 : {
4673 : /* Terminate hostname and evaluate port string */
4674 870 : *q++ = '\0';
4675 870 : http->port = atoi(q);
4676 : }
4677 : else
4678 : {
4679 14300 : http->port = 80;
4680 : }
4681 :
4682 : /* Rebuild request URL */
4683 15170 : freez(http->url);
4684 15170 : http->url = strdup("http://");
4685 15170 : string_append(&http->url, http->hostport);
4686 15170 : string_append(&http->url, http->path);
4687 15170 : if (http->url == NULL)
4688 : {
4689 0 : return JB_ERR_MEMORY;
4690 : }
4691 :
4692 15170 : log_error(LOG_LEVEL_HEADER,
4693 : "Destination extracted from \"Host\" header. New request URL: %s",
4694 : http->url);
4695 :
4696 : /*
4697 : * Regenerate request line in "proxy format"
4698 : * to make rewrites more convenient.
4699 : */
4700 15170 : assert(http->cmd != NULL);
4701 15170 : freez(http->cmd);
4702 15170 : http->cmd = strdup_or_die(http->gpc);
4703 15170 : string_append(&http->cmd, " ");
4704 15170 : string_append(&http->cmd, http->url);
4705 15170 : string_append(&http->cmd, " ");
4706 15170 : string_append(&http->cmd, http->version);
4707 15170 : if (http->cmd == NULL)
4708 : {
4709 0 : return JB_ERR_MEMORY;
4710 : }
4711 :
4712 15170 : return JB_ERR_OK;
4713 :
4714 : }
4715 :
4716 :
4717 : #ifdef FEATURE_HTTPS_INSPECTION
4718 : /*********************************************************************
4719 : *
4720 : * Function : get_destination_from_https_headers
4721 : *
4722 : * Description : Parse the previously encrypted "Host:" header to
4723 : * get the request's destination.
4724 : *
4725 : * Parameters :
4726 : * 1 : headers = List of headers (one of them hopefully being
4727 : * the "Host:" header)
4728 : * 2 : http = storage for the result (host, port and hostport).
4729 : *
4730 : * Returns : JB_ERR_MEMORY (or terminates) in case of memory problems,
4731 : * JB_ERR_PARSE if the host header couldn't be found,
4732 : * JB_ERR_OK otherwise.
4733 : *
4734 : *********************************************************************/
4735 2136 : jb_err get_destination_from_https_headers(const struct list *headers, struct http_request *http)
4736 : {
4737 : char *q;
4738 : char *p;
4739 : char *host;
4740 :
4741 2136 : host = get_header_value(headers, "Host:");
4742 :
4743 2136 : if (NULL == host)
4744 : {
4745 7 : log_error(LOG_LEVEL_ERROR, "No \"Host:\" header found.");
4746 7 : return JB_ERR_PARSE;
4747 : }
4748 :
4749 2129 : p = string_tolower(host);
4750 2129 : if (p == NULL)
4751 : {
4752 0 : return JB_ERR_MEMORY;
4753 : }
4754 2129 : chomp(p);
4755 2129 : q = strdup_or_die(p);
4756 :
4757 2129 : freez(http->hostport);
4758 2129 : http->hostport = p;
4759 2129 : freez(http->host);
4760 2129 : http->host = q;
4761 2129 : q = strchr(http->host, ':');
4762 2129 : if (q != NULL)
4763 : {
4764 : /* Terminate hostname and evaluate port string */
4765 57 : *q++ = '\0';
4766 57 : http->port = atoi(q);
4767 : }
4768 : else
4769 : {
4770 2072 : http->port = 443;
4771 : }
4772 :
4773 : /* Rebuild request URL */
4774 2129 : freez(http->url);
4775 2129 : http->url = strdup_or_die(http->path);
4776 :
4777 2129 : log_error(LOG_LEVEL_HEADER,
4778 : "Destination extracted from \"Host\" header. New request URL: %s",
4779 : http->url);
4780 :
4781 : /*
4782 : * Regenerate request line in "proxy format"
4783 : * to make rewrites more convenient.
4784 : */
4785 2129 : assert(http->cmd != NULL);
4786 2129 : freez(http->cmd);
4787 2129 : http->cmd = strdup_or_die(http->gpc);
4788 2129 : string_append(&http->cmd, " ");
4789 2129 : string_append(&http->cmd, http->url);
4790 2129 : string_append(&http->cmd, " ");
4791 2129 : string_append(&http->cmd, http->version);
4792 2129 : if (http->cmd == NULL)
4793 : {
4794 0 : return JB_ERR_MEMORY;
4795 : }
4796 :
4797 2129 : return JB_ERR_OK;
4798 :
4799 : }
4800 : #endif /* def FEATURE_HTTPS_INSPECTION */
4801 :
4802 :
4803 : /*********************************************************************
4804 : *
4805 : * Function : create_forged_referrer
4806 : *
4807 : * Description : Helper for client_referrer to forge a referer as
4808 : * 'http://hostname[:port]/' to fool stupid
4809 : * checks for in-site links
4810 : *
4811 : * Parameters :
4812 : * 1 : header = Pointer to header pointer
4813 : * 2 : hostport = Host and optionally port as string
4814 : *
4815 : * Returns : JB_ERR_OK in case of success, or
4816 : * JB_ERR_MEMORY in case of memory problems.
4817 : *
4818 : *********************************************************************/
4819 1441 : static jb_err create_forged_referrer(char **header, const char *hostport)
4820 : {
4821 1441 : assert(NULL == *header);
4822 :
4823 1441 : *header = strdup("Referer: http://");
4824 1441 : string_append(header, hostport);
4825 1441 : string_append(header, "/");
4826 :
4827 1441 : if (NULL == *header)
4828 : {
4829 0 : return JB_ERR_MEMORY;
4830 : }
4831 :
4832 1441 : log_error(LOG_LEVEL_HEADER, "Referer forged to: %s", *header);
4833 :
4834 1441 : return JB_ERR_OK;
4835 :
4836 : }
4837 :
4838 :
4839 : /*********************************************************************
4840 : *
4841 : * Function : create_fake_referrer
4842 : *
4843 : * Description : Helper for client_referrer to create a fake referrer
4844 : * based on a string supplied by the user.
4845 : *
4846 : * Parameters :
4847 : * 1 : header = Pointer to header pointer
4848 : * 2 : hosthost = Referrer to fake
4849 : *
4850 : * Returns : JB_ERR_OK in case of success, or
4851 : * JB_ERR_MEMORY in case of memory problems.
4852 : *
4853 : *********************************************************************/
4854 38 : static jb_err create_fake_referrer(char **header, const char *fake_referrer)
4855 : {
4856 38 : assert(NULL == *header);
4857 :
4858 38 : if ((0 != strncmpic(fake_referrer, "http://", 7)) && (0 != strncmpic(fake_referrer, "https://", 8)))
4859 : {
4860 38 : log_error(LOG_LEVEL_HEADER,
4861 : "Parameter: +hide-referrer{%s} is a bad idea, but I don't care.", fake_referrer);
4862 : }
4863 38 : *header = strdup("Referer: ");
4864 38 : string_append(header, fake_referrer);
4865 :
4866 38 : if (NULL == *header)
4867 : {
4868 0 : return JB_ERR_MEMORY;
4869 : }
4870 :
4871 38 : log_error(LOG_LEVEL_HEADER, "Referer replaced with: %s", *header);
4872 :
4873 38 : return JB_ERR_OK;
4874 :
4875 : }
4876 :
4877 :
4878 : /*********************************************************************
4879 : *
4880 : * Function : handle_conditional_hide_referrer_parameter
4881 : *
4882 : * Description : Helper for client_referrer to crunch or forge
4883 : * the referrer header if the host has changed.
4884 : *
4885 : * Parameters :
4886 : * 1 : header = Pointer to header pointer
4887 : * 2 : host = The target host (may include the port)
4888 : * 3 : parameter_conditional_block = Boolean to signal
4889 : * if we're in conditional-block mode. If not set,
4890 : * we're in conditional-forge mode.
4891 : *
4892 : * Returns : JB_ERR_OK in case of success, or
4893 : * JB_ERR_MEMORY in case of memory problems.
4894 : *
4895 : *********************************************************************/
4896 91 : static jb_err handle_conditional_hide_referrer_parameter(char **header,
4897 : const char *host, const int parameter_conditional_block)
4898 : {
4899 91 : char *referer = strdup_or_die(*header);
4900 91 : const size_t hostlength = strlen(host);
4901 91 : const char *referer_url = NULL;
4902 :
4903 : /* referer begins with 'Referer: http[s]://' */
4904 91 : if ((hostlength+17) < strlen(referer))
4905 : {
4906 : /*
4907 : * Shorten referer to make sure the referer is blocked
4908 : * if www.example.org/www.example.com-shall-see-the-referer/
4909 : * links to www.example.com/
4910 : */
4911 71 : referer[hostlength+17] = '\0';
4912 : }
4913 91 : referer_url = strstr(referer, "http://");
4914 91 : if (NULL == referer_url)
4915 : {
4916 51 : referer_url = strstr(referer, "https://");
4917 : }
4918 91 : if ((NULL == referer_url) || (NULL == strstr(referer_url, host)))
4919 : {
4920 : /* Host has changed, Referer is invalid or a https URL. */
4921 80 : if (parameter_conditional_block)
4922 : {
4923 80 : log_error(LOG_LEVEL_HEADER, "New host is: %s. Crunching %s!", host, *header);
4924 80 : freez(*header);
4925 : }
4926 : else
4927 : {
4928 0 : freez(*header);
4929 0 : freez(referer);
4930 0 : return create_forged_referrer(header, host);
4931 : }
4932 : }
4933 91 : freez(referer);
4934 :
4935 91 : return JB_ERR_OK;
4936 :
4937 : }
4938 :
4939 :
4940 : /*********************************************************************
4941 : *
4942 : * Function : create_content_length_header
4943 : *
4944 : * Description : Creates a Content-Length header.
4945 : *
4946 : * Parameters :
4947 : * 1 : content_length = The content length to be used in the header.
4948 : * 2 : header = Allocated space to safe the header.
4949 : * 3 : buffer_length = The length of the allocated space.
4950 : *
4951 : * Returns : void
4952 : *
4953 : *********************************************************************/
4954 1581 : static void create_content_length_header(unsigned long long content_length,
4955 : char *header, size_t buffer_length)
4956 : {
4957 : #ifdef _WIN32
4958 : #if SIZEOF_LONG_LONG < 8
4959 : #error sizeof(unsigned long long) too small
4960 : #endif
4961 : snprintf(header, buffer_length, "Content-Length: %I64u", content_length);
4962 : #else
4963 1581 : snprintf(header, buffer_length, "Content-Length: %llu", content_length);
4964 : #endif
4965 1581 : }
4966 :
4967 :
4968 : /*********************************************************************
4969 : *
4970 : * Function : get_expected_content_length
4971 : *
4972 : * Description : Figures out the content length from a list of headers.
4973 : *
4974 : * Parameters :
4975 : * 1 : headers = List of headers
4976 : *
4977 : * Returns : Number of bytes to expect
4978 : *
4979 : *********************************************************************/
4980 30624 : unsigned long long get_expected_content_length(struct list *headers)
4981 : {
4982 : const char *content_length_header;
4983 30624 : unsigned long long content_length = 0;
4984 :
4985 30624 : content_length_header = get_header_value(headers, "Content-Length:");
4986 30624 : if (content_length_header != NULL)
4987 : {
4988 1305 : if (JB_ERR_OK != get_content_length(content_length_header, &content_length))
4989 : {
4990 148 : log_error(LOG_LEVEL_ERROR,
4991 : "Failed to get the Content-Length in %s", content_length_header);
4992 : /* XXX: The header will be removed later on */
4993 148 : return 0;
4994 : }
4995 : }
4996 :
4997 30476 : return content_length;
4998 : }
4999 :
5000 :
5001 : /*
5002 : Local Variables:
5003 : tab-width: 3
5004 : end:
5005 : */
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