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1 /*********************************************************************
2  *
3  * File        :  $Source: /cvsroot/ijbswa/current/jcc.c,v $
4  *
5  * Purpose     :  Main file.  Contains main() method, main loop, and
6  *                the main connection-handling function.
7  *
8  * Copyright   :  Written by and Copyright (C) 2001-2022 the
9  *                Privoxy team. https://www.privoxy.org/
10  *
11  *                Based on the Internet Junkbuster originally written
12  *                by and Copyright (C) 1997 Anonymous Coders and
13  *                Junkbusters Corporation.  http://www.junkbusters.com
14  *
15  *                This program is free software; you can redistribute it
16  *                and/or modify it under the terms of the GNU General
17  *                Public License as published by the Free Software
18  *                Foundation; either version 2 of the License, or (at
19  *                your option) any later version.
20  *
21  *                This program is distributed in the hope that it will
22  *                be useful, but WITHOUT ANY WARRANTY; without even the
23  *                implied warranty of MERCHANTABILITY or FITNESS FOR A
24  *                PARTICULAR PURPOSE.  See the GNU General Public
25  *                License for more details.
26  *
27  *                The GNU General Public License should be included with
28  *                this file.  If not, you can view it at
29  *                http://www.gnu.org/copyleft/gpl.html
30  *                or write to the Free Software Foundation, Inc., 59
31  *                Temple Place - Suite 330, Boston, MA  02111-1307, USA.
32  *
33  *********************************************************************/
34
35
36 #include "config.h"
37
38 #include <stdio.h>
39 #include <sys/types.h>
40 #include <stdlib.h>
41 #include <string.h>
42 #include <signal.h>
43 #include <fcntl.h>
44 #include <errno.h>
45 #include <assert.h>
46
47 #ifdef _WIN32
48 # ifndef FEATURE_PTHREAD
49 #  ifndef STRICT
50 #   define STRICT
51 #  endif
52 #  include <winsock2.h>
53 #  include <windows.h>
54 #  include <process.h>
55 # endif /* ndef FEATURE_PTHREAD */
56
57 # include "win32.h"
58 # ifndef _WIN_CONSOLE
59 #  include "w32log.h"
60 # endif /* ndef _WIN_CONSOLE */
61 # include "w32svrapi.h"
62
63 #else /* ifndef _WIN32 */
64
65 # include <unistd.h>
66 # include <sys/wait.h>
67 # include <sys/time.h>
68 # include <sys/stat.h>
69 # include <sys/ioctl.h>
70
71 #ifdef sun
72 #include <sys/termios.h>
73 #endif /* sun */
74
75 #ifdef unix
76 #include <pwd.h>
77 #include <grp.h>
78 #endif
79
80 # include <signal.h>
81
82 # ifdef __BEOS__
83 #  include <socket.h>  /* BeOS has select() for sockets only. */
84 #  include <OS.h>      /* declarations for threads and stuff. */
85 # endif
86
87 #ifdef HAVE_POLL
88 #ifdef __GLIBC__
89 #include <sys/poll.h>
90 #else
91 #include <poll.h>
92 #endif /* def __GLIBC__ */
93 #else
94 # ifndef FD_ZERO
95 #  include <select.h>
96 # endif
97 #warning poll() appears to be unavailable. Your platform will become unsupported in the future.
98 #endif /* HAVE_POLL */
99
100 #endif
101
102 #include "project.h"
103 #include "list.h"
104 #include "jcc.h"
105 #ifdef FEATURE_HTTPS_INSPECTION
106 #include "ssl.h"
107 #endif
108 #include "filters.h"
109 #include "loaders.h"
110 #include "parsers.h"
111 #include "miscutil.h"
112 #include "errlog.h"
113 #include "jbsockets.h"
114 #include "gateway.h"
115 #include "actions.h"
116 #include "cgi.h"
117 #include "loadcfg.h"
118 #include "urlmatch.h"
119 #ifdef FEATURE_CLIENT_TAGS
120 #include "client-tags.h"
121 #endif
122
123 int daemon_mode = 1;
124 struct client_states clients[1];
125 struct file_list     files[1];
126
127 #ifdef FEATURE_STATISTICS
128 int urls_read     = 0;     /* total nr of urls read inc rejected */
129 int urls_rejected = 0;     /* total nr of urls rejected */
130 #ifdef MUTEX_LOCKS_AVAILABLE
131 unsigned long long number_of_requests_received = 0;
132 unsigned long long number_of_requests_blocked = 0;
133 #endif
134 #endif /* def FEATURE_STATISTICS */
135
136 #ifdef FEATURE_GRACEFUL_TERMINATION
137 int g_terminate = 0;
138 #endif
139
140 #if !defined(_WIN32)
141 static void sig_handler(int the_signal);
142 #endif
143 static int client_protocol_is_unsupported(struct client_state *csp, char *req);
144 static jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers);
145 static jb_err get_server_headers(struct client_state *csp);
146 static const char *crunch_reason(const struct http_response *rsp);
147 static void send_crunch_response(struct client_state *csp, struct http_response *rsp);
148 static char *get_request_line(struct client_state *csp);
149 static jb_err receive_client_request(struct client_state *csp);
150 static jb_err parse_client_request(struct client_state *csp);
151 static void build_request_line(struct client_state *csp, const struct forward_spec *fwd, char **request_line);
152 static jb_err change_request_destination(struct client_state *csp);
153 static void handle_established_connection(struct client_state *csp);
154 static void chat(struct client_state *csp);
155 static void serve(struct client_state *csp);
156 #if !defined(_WIN32) || defined(_WIN_CONSOLE)
157 static void usage(const char *myname);
158 #endif
159 static void initialize_mutexes(void);
160 static jb_socket bind_port_helper(const char *haddr, int hport, int backlog);
161 static void bind_ports_helper(struct configuration_spec *config, jb_socket sockets[]);
162 static void close_ports_helper(jb_socket sockets[]);
163 static void listen_loop(void);
164 static void serve(struct client_state *csp);
165
166 #ifdef __BEOS__
167 static int32 server_thread(void *data);
168 #endif /* def __BEOS__ */
169
170 #ifdef _WIN32
171 #define sleep(N)  Sleep(((N) * 1000))
172 #endif
173
174 #ifdef FUZZ
175 int process_fuzzed_input(char *fuzz_input_type, char *fuzz_input_file);
176 void show_fuzz_usage(const char *name);
177 #endif
178
179 #ifdef MUTEX_LOCKS_AVAILABLE
180 /*
181  * XXX: Does the locking stuff really belong in this file?
182  */
183 privoxy_mutex_t log_mutex;
184 privoxy_mutex_t log_init_mutex;
185 privoxy_mutex_t connection_reuse_mutex;
186
187 #ifdef FEATURE_HTTPS_INSPECTION
188 privoxy_mutex_t certificate_mutex;
189 privoxy_mutex_t ssl_init_mutex;
190 #endif
191
192 #ifdef FEATURE_EXTERNAL_FILTERS
193 privoxy_mutex_t external_filter_mutex;
194 #endif
195 #ifdef FEATURE_CLIENT_TAGS
196 privoxy_mutex_t client_tags_mutex;
197 #endif
198 #ifdef FEATURE_STATISTICS
199 privoxy_mutex_t block_statistics_mutex;
200 #endif
201 #ifdef FEATURE_EXTENDED_STATISTICS
202 privoxy_mutex_t filter_statistics_mutex;
203 privoxy_mutex_t block_reason_statistics_mutex;
204 #endif
205
206 #if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R)
207 privoxy_mutex_t resolver_mutex;
208 #endif /* !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R) */
209
210 #ifndef HAVE_GMTIME_R
211 privoxy_mutex_t gmtime_mutex;
212 #endif /* ndef HAVE_GMTIME_R */
213
214 #ifndef HAVE_LOCALTIME_R
215 privoxy_mutex_t localtime_mutex;
216 #endif /* ndef HAVE_GMTIME_R */
217
218 #if !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM)
219 privoxy_mutex_t rand_mutex;
220 #endif /* !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM) */
221
222 #endif /* def MUTEX_LOCKS_AVAILABLE */
223
224 #if defined(unix)
225 const char *basedir = NULL;
226 const char *pidfile = NULL;
227 static int received_hup_signal = 0;
228 #endif /* defined unix */
229
230 /* HTTP snipplets. */
231 static const char CSUCCEED[] =
232    "HTTP/1.1 200 Connection established\r\n\r\n";
233
234 static const char CHEADER[] =
235    "HTTP/1.1 400 Invalid header received from client\r\n"
236    "Content-Type: text/plain\r\n"
237    "Connection: close\r\n\r\n"
238    "Invalid header received from client.\n";
239
240 static const char FTP_RESPONSE[] =
241    "HTTP/1.1 400 Invalid request received from client\r\n"
242    "Content-Type: text/plain\r\n"
243    "Connection: close\r\n\r\n"
244    "Invalid request. Privoxy doesn't support FTP.\n";
245
246 static const char GOPHER_RESPONSE[] =
247    "HTTP/1.1 400 Invalid request received from client\r\n"
248    "Content-Type: text/plain\r\n"
249    "Connection: close\r\n\r\n"
250    "Invalid request. Privoxy doesn't support gopher.\n";
251
252 /* XXX: should be a template */
253 static const char MISSING_DESTINATION_RESPONSE[] =
254    "HTTP/1.1 400 Bad request received from client\r\n"
255    "Content-Type: text/plain\r\n"
256    "Connection: close\r\n\r\n"
257    "Bad request. Privoxy was unable to extract the destination.\n";
258
259 /* XXX: should be a template */
260 static const char INVALID_SERVER_HEADERS_RESPONSE[] =
261    "HTTP/1.1 502 Server or forwarder response invalid\r\n"
262    "Content-Type: text/plain\r\n"
263    "Connection: close\r\n\r\n"
264    "Bad response. The server or forwarder response doesn't look like HTTP.\n";
265
266 /* XXX: should be a template */
267 static const char MESSED_UP_REQUEST_RESPONSE[] =
268    "HTTP/1.1 400 Malformed request after rewriting\r\n"
269    "Content-Type: text/plain\r\n"
270    "Connection: close\r\n\r\n"
271    "Bad request. Messed up with header filters.\n";
272
273 static const char TOO_MANY_CONNECTIONS_RESPONSE[] =
274    "HTTP/1.1 503 Too many open connections\r\n"
275    "Content-Type: text/plain\r\n"
276    "Connection: close\r\n\r\n"
277    "Maximum number of open connections reached.\n";
278
279 static const char CLIENT_CONNECTION_TIMEOUT_RESPONSE[] =
280    "HTTP/1.1 504 Connection timeout\r\n"
281    "Content-Type: text/plain\r\n"
282    "Connection: close\r\n\r\n"
283    "The connection timed out because the client request didn't arrive in time.\n";
284
285 static const char CLIENT_BODY_PARSE_ERROR_RESPONSE[] =
286    "HTTP/1.1 400 Failed reading client body\r\n"
287    "Content-Type: text/plain\r\n"
288    "Connection: close\r\n\r\n"
289    "Failed parsing or buffering the chunk-encoded client body.\n";
290
291 static const char CLIENT_BODY_BUFFER_ERROR_RESPONSE[] =
292    "HTTP/1.1 400 Failed reading client body\r\n"
293    "Content-Type: text/plain\r\n"
294    "Connection: close\r\n\r\n"
295    "Failed to buffer the client body to apply content filters.\n"
296    "Could be caused by a socket timeout\n";
297
298 static const char UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE[] =
299    "HTTP/1.1 417 Expecting too much\r\n"
300    "Content-Type: text/plain\r\n"
301    "Connection: close\r\n\r\n"
302    "Privoxy detected an unsupported Expect header value.\n";
303
304 /* A function to crunch a response */
305 typedef struct http_response *(*crunch_func_ptr)(struct client_state *);
306
307 /* Crunch function flags */
308 #define CF_NO_FLAGS        0
309 /* Cruncher applies to forced requests as well */
310 #define CF_IGNORE_FORCE    1
311 /* Crunched requests are counted for the block statistics */
312 #define CF_COUNT_AS_REJECT 2
313
314 /* A crunch function and its flags */
315 struct cruncher
316 {
317    const crunch_func_ptr cruncher;
318    const int flags;
319 };
320
321 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[]);
322
323 /* Complete list of cruncher functions */
324 static const struct cruncher crunchers_all[] = {
325    { direct_response, CF_COUNT_AS_REJECT|CF_IGNORE_FORCE},
326    { block_url,       CF_COUNT_AS_REJECT },
327 #ifdef FEATURE_TRUST
328    { trust_url,       CF_COUNT_AS_REJECT },
329 #endif /* def FEATURE_TRUST */
330    { redirect_url,    CF_NO_FLAGS  },
331    { dispatch_cgi,    CF_IGNORE_FORCE},
332    { NULL,            0 }
333 };
334
335 /* Light version, used after tags are applied */
336 static const struct cruncher crunchers_light[] = {
337    { block_url,       CF_COUNT_AS_REJECT },
338    { redirect_url,    CF_NO_FLAGS },
339    { NULL,            0 }
340 };
341
342
343 /*
344  * XXX: Don't we really mean
345  *
346  * #if defined(unix)
347  *
348  * here?
349  */
350 #if !defined(_WIN32)
351 /*********************************************************************
352  *
353  * Function    :  sig_handler
354  *
355  * Description :  Signal handler for different signals.
356  *                Exit gracefully on TERM and INT
357  *                or set a flag that will cause the errlog
358  *                to be reopened by the main thread on HUP.
359  *
360  * Parameters  :
361  *          1  :  the_signal = the signal cause this function to call
362  *
363  * Returns     :  -
364  *
365  *********************************************************************/
366 static void sig_handler(int the_signal)
367 {
368    switch(the_signal)
369    {
370       case SIGTERM:
371       case SIGINT:
372          log_error(LOG_LEVEL_INFO, "exiting by signal %d .. bye", the_signal);
373 #if defined(unix)
374          if (pidfile)
375          {
376             unlink(pidfile);
377          }
378 #endif /* unix */
379          exit(the_signal);
380          break;
381
382       case SIGHUP:
383 #if defined(unix)
384          received_hup_signal = 1;
385 #endif
386          break;
387
388       default:
389          /*
390           * We shouldn't be here, unless we catch signals
391           * in main() that we can't handle here!
392           */
393          log_error(LOG_LEVEL_FATAL,
394             "sig_handler: exiting on unexpected signal %d", the_signal);
395    }
396    return;
397
398 }
399 #endif
400
401
402 /*********************************************************************
403  *
404  * Function    :  get_write_delay
405  *
406  * Description :  Parse the delay-response parameter.
407  *
408  * Parameters  :
409  *          1  :  csp = Current client state (buffers, headers, etc...)
410  *
411  * Returns     :  Number of milliseconds to delay writes.
412  *
413  *********************************************************************/
414 static unsigned int get_write_delay(const struct client_state *csp)
415 {
416    unsigned int delay;
417    char *endptr;
418    char *newval;
419
420    if ((csp->action->flags & ACTION_DELAY_RESPONSE) == 0)
421    {
422       return 0;
423    }
424    newval = csp->action->string[ACTION_STRING_DELAY_RESPONSE];
425
426    delay = (unsigned)strtol(newval, &endptr, 0);
427    if (*endptr != '\0')
428    {
429       log_error(LOG_LEVEL_FATAL,
430          "Invalid delay-response{} parameter: '%s'", newval);
431    }
432
433    return delay;
434
435 }
436
437
438 /*********************************************************************
439  *
440  * Function    :  client_protocol_is_unsupported
441  *
442  * Description :  Checks if the client used a known unsupported
443  *                protocol and deals with it by sending an error
444  *                response.
445  *
446  * Parameters  :
447  *          1  :  csp = Current client state (buffers, headers, etc...)
448  *          2  :  req = the first request line send by the client
449  *
450  * Returns     :  TRUE if an error response has been generated, or
451  *                FALSE if the request doesn't look invalid.
452  *
453  *********************************************************************/
454 static int client_protocol_is_unsupported(struct client_state *csp, char *req)
455 {
456    /*
457     * If it's a FTP or gopher request, we don't support it.
458     *
459     * These checks are better than nothing, but they might
460     * not work in all configurations and some clients might
461     * have problems digesting the answer.
462     *
463     * They should, however, never cause more problems than
464     * Privoxy's old behaviour (returning the misleading HTML
465     * error message:
466     *
467     * "Could not resolve http://(ftp|gopher)://example.org").
468     */
469    if (!strncmpic(req, "GET ftp://", 10) || !strncmpic(req, "GET gopher://", 13))
470    {
471       const char *response = NULL;
472       const char *protocol = NULL;
473
474       if (!strncmpic(req, "GET ftp://", 10))
475       {
476          response = FTP_RESPONSE;
477          protocol = "FTP";
478       }
479       else
480       {
481          response = GOPHER_RESPONSE;
482          protocol = "GOPHER";
483       }
484       log_error(LOG_LEVEL_ERROR,
485          "%s tried to use Privoxy as %s proxy: %s",
486          csp->ip_addr_str, protocol, req);
487       log_error(LOG_LEVEL_CLF,
488          "%s - - [%T] \"%s\" 400 0", csp->ip_addr_str, req);
489       freez(req);
490
491 #ifdef FEATURE_HTTPS_INSPECTION
492       if (client_use_ssl(csp))
493       {
494          ssl_send_data_delayed(&(csp->ssl_client_attr),
495             (const unsigned char *)response, strlen(response),
496             get_write_delay(csp));
497       }
498       else
499 #endif
500       {
501          write_socket_delayed(csp->cfd, response, strlen(response),
502             get_write_delay(csp));
503       }
504
505       return TRUE;
506    }
507
508    return FALSE;
509 }
510
511
512 /*********************************************************************
513  *
514  * Function    :  client_has_unsupported_expectations
515  *
516  * Description :  Checks if the client used an unsupported expectation
517  *                in which case an error message is delivered.
518  *
519  * Parameters  :
520  *          1  :  csp = Current client state (buffers, headers, etc...)
521  *
522  * Returns     :  TRUE if an error response has been generated, or
523  *                FALSE if the request doesn't look invalid.
524  *
525  *********************************************************************/
526 static int client_has_unsupported_expectations(const struct client_state *csp)
527 {
528    if ((csp->flags & CSP_FLAG_UNSUPPORTED_CLIENT_EXPECTATION))
529    {
530       log_error(LOG_LEVEL_ERROR,
531          "Rejecting request from client %s with unsupported Expect header value",
532          csp->ip_addr_str);
533       log_error(LOG_LEVEL_CLF,
534          "%s - - [%T] \"%s\" 417 0", csp->ip_addr_str, csp->http->cmd);
535       write_socket_delayed(csp->cfd,
536          UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE,
537          strlen(UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE),
538          get_write_delay(csp));
539
540       return TRUE;
541    }
542
543    return FALSE;
544
545 }
546
547
548 /*********************************************************************
549  *
550  * Function    :  get_request_destination_elsewhere
551  *
552  * Description :  If the client's request was redirected into
553  *                Privoxy without the client's knowledge,
554  *                the request line lacks the destination host.
555  *
556  *                This function tries to get it elsewhere,
557  *                provided accept-intercepted-requests is enabled.
558  *
559  *                "Elsewhere" currently only means "Host: header",
560  *                but in the future we may ask the redirecting
561  *                packet filter to look the destination up.
562  *
563  *                If the destination stays unknown, an error
564  *                response is send to the client and headers
565  *                are freed so that chat() can return directly.
566  *
567  * Parameters  :
568  *          1  :  csp = Current client state (buffers, headers, etc...)
569  *          2  :  headers = a header list
570  *
571  * Returns     :  JB_ERR_OK if the destination is now known, or
572  *                JB_ERR_PARSE if it isn't.
573  *
574  *********************************************************************/
575 static jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers)
576 {
577    if (!(csp->config->feature_flags & RUNTIME_FEATURE_ACCEPT_INTERCEPTED_REQUESTS))
578    {
579       log_error(LOG_LEVEL_ERROR, "%s's request: \'%s\' is invalid."
580          " Privoxy isn't configured to accept intercepted requests.",
581          csp->ip_addr_str, csp->http->cmd);
582       /* XXX: Use correct size */
583       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
584          csp->ip_addr_str, csp->http->cmd);
585
586       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
587          get_write_delay(csp));
588       destroy_list(headers);
589
590       return JB_ERR_PARSE;
591    }
592    else if (JB_ERR_OK == get_destination_from_headers(headers, csp->http))
593    {
594       /* Split the domain we just got for pattern matching */
595       init_domain_components(csp->http);
596
597       return JB_ERR_OK;
598    }
599    else
600    {
601       /* We can't work without destination. Go spread the news.*/
602
603       /* XXX: Use correct size */
604       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
605          csp->ip_addr_str, csp->http->cmd);
606       log_error(LOG_LEVEL_ERROR,
607          "Privoxy was unable to get the destination for %s's request: %s",
608          csp->ip_addr_str, csp->http->cmd);
609
610       write_socket_delayed(csp->cfd, MISSING_DESTINATION_RESPONSE,
611          strlen(MISSING_DESTINATION_RESPONSE), get_write_delay(csp));
612       destroy_list(headers);
613
614       return JB_ERR_PARSE;
615    }
616    /*
617     * TODO: If available, use PF's ioctl DIOCNATLOOK as last resort
618     * to get the destination IP address, use it as host directly
619     * or do a reverse DNS lookup first.
620     */
621 }
622
623
624 /*********************************************************************
625  *
626  * Function    :  get_server_headers
627  *
628  * Description :  Parses server headers in iob and fills them
629  *                into csp->headers so that they can later be
630  *                handled by sed().
631  *
632  * Parameters  :
633  *          1  :  csp = Current client state (buffers, headers, etc...)
634  *
635  * Returns     :  JB_ERR_OK if everything went fine, or
636  *                JB_ERR_PARSE if the headers were incomplete.
637  *
638  *********************************************************************/
639 static jb_err get_server_headers(struct client_state *csp)
640 {
641    int continue_hack_in_da_house = 0;
642    char * header;
643
644    while (((header = get_header(csp->iob)) != NULL) || continue_hack_in_da_house)
645    {
646       if (header == NULL)
647       {
648          /*
649           * continue hack in da house. Ignore the ending of
650           * this head and continue enlisting header lines.
651           * The reason is described below.
652           */
653          enlist(csp->headers, "");
654          continue_hack_in_da_house = 0;
655          continue;
656       }
657       else if (0 == strncmpic(header, "HTTP/1.1 100", 12))
658       {
659          /*
660           * It's a bodyless continue response, don't
661           * stop header parsing after reaching its end.
662           *
663           * As a result Privoxy will concatenate the
664           * next response's head and parse and deliver
665           * the headers as if they belonged to one request.
666           *
667           * The client will separate them because of the
668           * empty line between them.
669           *
670           * XXX: What we're doing here is clearly against
671           * the intended purpose of the continue header,
672           * and under some conditions (HTTP/1.0 client request)
673           * it's a standard violation.
674           *
675           * Anyway, "sort of against the spec" is preferable
676           * to "always getting confused by Continue responses"
677           * (Privoxy's behaviour before this hack was added)
678           */
679          log_error(LOG_LEVEL_HEADER, "Continue hack in da house.");
680          continue_hack_in_da_house = 1;
681       }
682       else if (*header == '\0')
683       {
684          /*
685           * If the header is empty, but the Continue hack
686           * isn't active, we can assume that we reached the
687           * end of the buffer before we hit the end of the
688           * head.
689           *
690           * Inform the caller an let it decide how to handle it.
691           */
692          return JB_ERR_PARSE;
693       }
694
695       if (JB_ERR_MEMORY == enlist(csp->headers, header))
696       {
697          /*
698           * XXX: Should we quit the request and return a
699           * out of memory error page instead?
700           */
701          log_error(LOG_LEVEL_ERROR,
702             "Out of memory while enlisting server headers. %s lost.",
703             header);
704       }
705       freez(header);
706    }
707
708    return JB_ERR_OK;
709 }
710
711
712 /*********************************************************************
713  *
714  * Function    :  crunch_reason
715  *
716  * Description :  Translates the crunch reason code into a string.
717  *
718  * Parameters  :
719  *          1  :  rsp = a http_response
720  *
721  * Returns     :  A string with the crunch reason or an error description.
722  *
723  *********************************************************************/
724 static const char *crunch_reason(const struct http_response *rsp)
725 {
726    char * reason = NULL;
727
728    assert(rsp != NULL);
729    if (rsp == NULL)
730    {
731       return "Internal error while searching for crunch reason";
732    }
733
734    switch (rsp->crunch_reason)
735    {
736       case UNSUPPORTED:
737          reason = "Unsupported HTTP feature";
738          break;
739       case BLOCKED:
740          reason = "Blocked";
741          break;
742       case UNTRUSTED:
743          reason = "Untrusted";
744          break;
745       case REDIRECTED:
746          reason = "Redirected";
747          break;
748       case CGI_CALL:
749          reason = "CGI Call";
750          break;
751       case NO_SUCH_DOMAIN:
752          reason = "DNS failure";
753          break;
754       case FORWARDING_FAILED:
755          reason = "Forwarding failed";
756          break;
757       case CONNECT_FAILED:
758          reason = "Connection failure";
759          break;
760       case OUT_OF_MEMORY:
761          reason = "Out of memory (may mask other reasons)";
762          break;
763       case CONNECTION_TIMEOUT:
764          reason = "Connection timeout";
765          break;
766       case NO_SERVER_DATA:
767          reason = "No server data received";
768          break;
769       default:
770          reason = "No reason recorded";
771          break;
772    }
773
774    return reason;
775 }
776
777
778 /*********************************************************************
779  *
780  * Function    :  log_applied_actions
781  *
782  * Description :  Logs the applied actions if LOG_LEVEL_ACTIONS is
783  *                enabled.
784  *
785  * Parameters  :
786  *          1  :  actions = Current action spec to log
787  *
788  * Returns     :  Nothing.
789  *
790  *********************************************************************/
791 static void log_applied_actions(const struct current_action_spec *actions)
792 {
793    /*
794     * The conversion to text requires lots of memory allocations so
795     * we only do the conversion if the user is actually interested.
796     */
797    if (debug_level_is_enabled(LOG_LEVEL_ACTIONS))
798    {
799       char *actions_as_text = actions_to_line_of_text(actions);
800       log_error(LOG_LEVEL_ACTIONS, "%s", actions_as_text);
801       freez(actions_as_text);
802    }
803 }
804
805
806 /*********************************************************************
807  *
808  * Function    :  send_crunch_response
809  *
810  * Description :  Delivers already prepared response for
811  *                intercepted requests, logs the interception
812  *                and frees the response.
813  *
814  * Parameters  :
815  *          1  :  csp = Current client state (buffers, headers, etc...)
816  *          2  :  rsp = Fully prepared response. Will be freed on exit.
817  *
818  * Returns     :  Nothing.
819  *
820  *********************************************************************/
821 static void send_crunch_response(struct client_state *csp, struct http_response *rsp)
822 {
823       const struct http_request *http = csp->http;
824       char status_code[4];
825
826       assert(rsp != NULL);
827       assert(rsp->head != NULL);
828
829       if (rsp == NULL)
830       {
831          log_error(LOG_LEVEL_FATAL, "NULL response in send_crunch_response.");
832       }
833
834       /*
835        * Extract the status code from the actual head
836        * that will be send to the client. It is the only
837        * way to get it right for all requests, including
838        * the fixed ones for out-of-memory problems.
839        *
840        * A head starts like this: 'HTTP/1.1 200...'
841        *                           0123456789|11
842        *                                     10
843        */
844       status_code[0] = rsp->head[9];
845       status_code[1] = rsp->head[10];
846       status_code[2] = rsp->head[11];
847       status_code[3] = '\0';
848
849       /* Log that the request was crunched and why. */
850       log_applied_actions(csp->action);
851 #ifdef FEATURE_HTTPS_INSPECTION
852       if (client_use_ssl(csp))
853       {
854          log_error(LOG_LEVEL_CRUNCH, "%s: https://%s%s", crunch_reason(rsp),
855             http->hostport, http->path);
856          log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s https://%s%s %s\" %s %lu",
857             csp->ip_addr_str, http->gpc, http->hostport, http->path,
858             http->version, status_code, rsp->content_length);
859       }
860       else
861 #endif
862       {
863          log_error(LOG_LEVEL_CRUNCH, "%s: %s", crunch_reason(rsp), http->url);
864          log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" %s %lu",
865             csp->ip_addr_str, http->ocmd, status_code, rsp->content_length);
866       }
867       /* Write the answer to the client */
868 #ifdef FEATURE_HTTPS_INSPECTION
869       if (client_use_ssl(csp))
870       {
871          if ((ssl_send_data_delayed(&(csp->ssl_client_attr),
872                 (const unsigned char *)rsp->head, rsp->head_length,
873                 get_write_delay(csp)) < 0)
874           || (ssl_send_data_delayed(&(csp->ssl_client_attr),
875                 (const unsigned char *)rsp->body, rsp->content_length,
876                 get_write_delay(csp)) < 0))
877          {
878             /* There is nothing we can do about it. */
879             log_error(LOG_LEVEL_CONNECT, "Couldn't deliver the error message "
880                "for https://%s%s through client socket %d using TLS/SSL",
881                http->hostport, http->url, csp->cfd);
882          }
883       }
884       else
885 #endif
886       {
887          if (write_socket_delayed(csp->cfd, rsp->head, rsp->head_length,
888                 get_write_delay(csp))
889           || write_socket_delayed(csp->cfd, rsp->body, rsp->content_length,
890                 get_write_delay(csp)))
891          {
892             /* There is nothing we can do about it. */
893             log_error(LOG_LEVEL_CONNECT,
894                "Couldn't deliver the error message for %s through client socket %d: %E",
895                http->url, csp->cfd);
896          }
897       }
898
899       /* Clean up and return */
900       if (cgi_error_memory() != rsp)
901       {
902          free_http_response(rsp);
903       }
904       return;
905 }
906
907
908 /*********************************************************************
909  *
910  * Function    :  crunch_response_triggered
911  *
912  * Description :  Checks if the request has to be crunched,
913  *                and delivers the crunch response if necessary.
914  *
915  * Parameters  :
916  *          1  :  csp = Current client state (buffers, headers, etc...)
917  *          2  :  crunchers = list of cruncher functions to run
918  *
919  * Returns     :  TRUE if the request was answered with a crunch response
920  *                FALSE otherwise.
921  *
922  *********************************************************************/
923 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[])
924 {
925    struct http_response *rsp = NULL;
926    const struct cruncher *c;
927
928    /*
929     * If CGI request crunching is disabled,
930     * check the CGI dispatcher out of order to
931     * prevent unintentional blocks or redirects.
932     */
933    if (!(csp->config->feature_flags & RUNTIME_FEATURE_CGI_CRUNCHING)
934        && (NULL != (rsp = dispatch_cgi(csp))))
935    {
936       /* Deliver, log and free the interception response. */
937       send_crunch_response(csp, rsp);
938       csp->flags |= CSP_FLAG_CRUNCHED;
939       return TRUE;
940    }
941
942    for (c = crunchers; c->cruncher != NULL; c++)
943    {
944       /*
945        * Check the cruncher if either Privoxy is toggled
946        * on and the request isn't forced, or if the cruncher
947        * applies to forced requests as well.
948        */
949       if (((csp->flags & CSP_FLAG_TOGGLED_ON) &&
950           !(csp->flags & CSP_FLAG_FORCED)) ||
951           (c->flags & CF_IGNORE_FORCE))
952       {
953          rsp = c->cruncher(csp);
954          if (NULL != rsp)
955          {
956             /* Deliver, log and free the interception response. */
957             send_crunch_response(csp, rsp);
958             csp->flags |= CSP_FLAG_CRUNCHED;
959 #ifdef FEATURE_STATISTICS
960             if (c->flags & CF_COUNT_AS_REJECT)
961             {
962 #ifdef MUTEX_LOCKS_AVAILABLE
963                privoxy_mutex_lock(&block_statistics_mutex);
964                number_of_requests_blocked++;
965                privoxy_mutex_unlock(&block_statistics_mutex);
966 #endif
967                csp->flags |= CSP_FLAG_REJECTED;
968             }
969 #endif /* def FEATURE_STATISTICS */
970
971             return TRUE;
972          }
973       }
974    }
975
976    return FALSE;
977 }
978
979
980 /*********************************************************************
981  *
982  * Function    :  build_request_line
983  *
984  * Description :  Builds the HTTP request line.
985  *
986  *                If a HTTP forwarder is used it expects the whole URL,
987  *                web servers only get the path.
988  *
989  * Parameters  :
990  *          1  :  csp = Current client state (buffers, headers, etc...)
991  *          2  :  fwd = The forwarding spec used for the request.
992  *                      Can be NULL.
993  *          3  :  request_line = The old request line which will be replaced.
994  *
995  * Returns     :  Nothing. Terminates in case of memory problems.
996  *
997  *********************************************************************/
998 static void build_request_line(struct client_state *csp, const struct forward_spec *fwd, char **request_line)
999 {
1000    struct http_request *http = csp->http;
1001
1002    /*
1003     * Downgrade http version from 1.1 to 1.0
1004     * if +downgrade action applies.
1005     */
1006    if ((csp->action->flags & ACTION_DOWNGRADE)
1007      && (!strcmpic(http->version, "HTTP/1.1")))
1008    {
1009       freez(http->version);
1010       http->version = strdup_or_die("HTTP/1.0");
1011    }
1012
1013    /*
1014     * Rebuild the request line.
1015     */
1016    freez(*request_line);
1017 #ifdef FEATURE_HTTPS_INSPECTION
1018    if (fwd != NULL && fwd->forward_host &&
1019        fwd->type != FORWARD_WEBSERVER && client_use_ssl(csp))
1020    {
1021       *request_line = strdup("CONNECT ");
1022    }
1023    else
1024 #endif
1025    {
1026       *request_line = strdup(http->gpc);
1027       string_append(request_line, " ");
1028    }
1029
1030    if (fwd != NULL && fwd->forward_host && fwd->type != FORWARD_WEBSERVER)
1031    {
1032 #ifdef FEATURE_HTTPS_INSPECTION
1033       if (client_use_ssl(csp))
1034       {
1035          char port_string[10];
1036
1037          string_append(request_line, http->host);
1038          snprintf(port_string, sizeof(port_string), ":%d", http->port);
1039          string_append(request_line, port_string);
1040       }
1041       else
1042 #endif
1043       {
1044          string_append(request_line, http->url);
1045       }
1046    }
1047    else
1048    {
1049       string_append(request_line, http->path);
1050    }
1051    string_append(request_line, " ");
1052    string_append(request_line, http->version);
1053
1054    if (*request_line == NULL)
1055    {
1056       log_error(LOG_LEVEL_FATAL, "Out of memory writing HTTP command");
1057    }
1058    log_error(LOG_LEVEL_HEADER, "New HTTP Request-Line: %s", *request_line);
1059 }
1060
1061
1062 /*********************************************************************
1063  *
1064  * Function    :  change_request_destination
1065  *
1066  * Description :  Parse a (rewritten) request line and regenerate
1067  *                the http request data.
1068  *
1069  * Parameters  :
1070  *          1  :  csp = Current client state (buffers, headers, etc...)
1071  *
1072  * Returns     :  Forwards the parse_http_request() return code.
1073  *                Terminates in case of memory problems.
1074  *
1075  *********************************************************************/
1076 static jb_err change_request_destination(struct client_state *csp)
1077 {
1078    struct http_request *http = csp->http;
1079    jb_err err;
1080
1081    log_error(LOG_LEVEL_REDIRECTS, "Rewrite detected: %s",
1082       csp->headers->first->str);
1083    free_http_request(http);
1084    err = parse_http_request(csp->headers->first->str, http);
1085    if (JB_ERR_OK != err)
1086    {
1087       log_error(LOG_LEVEL_ERROR, "Couldn't parse rewritten request: %s.",
1088          jb_err_to_string(err));
1089    }
1090    if (http->ssl && strcmpic(csp->http->gpc, "CONNECT"))
1091    {
1092       /*
1093        * A client header filter changed the request URL from
1094        * http:// to https:// which we currently don't support.
1095        */
1096       log_error(LOG_LEVEL_ERROR, "Changing the request destination from http "
1097          "to https behind the client's back currently isn't supported.");
1098       return JB_ERR_PARSE;
1099    }
1100
1101    return err;
1102 }
1103
1104
1105 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1106 /*********************************************************************
1107  *
1108  * Function    :  server_response_is_complete
1109  *
1110  * Description :  Determines whether we should stop reading
1111  *                from the server socket.
1112  *
1113  * Parameters  :
1114  *          1  :  csp = Current client state (buffers, headers, etc...)
1115  *          2  :  content_length = Length of content received so far.
1116  *
1117  * Returns     :  TRUE if the response is complete,
1118  *                FALSE otherwise.
1119  *
1120  *********************************************************************/
1121 static int server_response_is_complete(struct client_state *csp,
1122    unsigned long long content_length)
1123 {
1124    int content_length_known = !!(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET);
1125
1126    if (!strcmpic(csp->http->gpc, "HEAD"))
1127    {
1128       /*
1129        * "HEAD" implies no body, we are thus expecting
1130        * no content. XXX: incomplete "list" of methods?
1131        */
1132       csp->expected_content_length = 0;
1133       content_length_known = TRUE;
1134       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1135    }
1136
1137    if (csp->http->status == 204 || csp->http->status == 304)
1138    {
1139       /*
1140        * Expect no body. XXX: incomplete "list" of status codes?
1141        */
1142       csp->expected_content_length = 0;
1143       content_length_known = TRUE;
1144       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1145    }
1146
1147    return (content_length_known && ((0 == csp->expected_content_length)
1148             || (csp->expected_content_length <= content_length)));
1149 }
1150
1151
1152 #ifdef FEATURE_CONNECTION_SHARING
1153 /*********************************************************************
1154  *
1155  * Function    :  wait_for_alive_connections
1156  *
1157  * Description :  Waits for alive connections to timeout.
1158  *
1159  * Parameters  :  N/A
1160  *
1161  * Returns     :  N/A
1162  *
1163  *********************************************************************/
1164 static void wait_for_alive_connections(void)
1165 {
1166    int connections_alive = close_unusable_connections();
1167
1168    while (0 < connections_alive)
1169    {
1170       log_error(LOG_LEVEL_CONNECT,
1171          "Waiting for %d connections to timeout.",
1172          connections_alive);
1173       sleep(60);
1174       connections_alive = close_unusable_connections();
1175    }
1176
1177    log_error(LOG_LEVEL_CONNECT, "No connections to wait for left.");
1178
1179 }
1180 #endif /* def FEATURE_CONNECTION_SHARING */
1181
1182
1183 /*********************************************************************
1184  *
1185  * Function    :  save_connection_destination
1186  *
1187  * Description :  Remembers a connection for reuse later on.
1188  *
1189  * Parameters  :
1190  *          1  :  sfd  = Open socket to remember.
1191  *          2  :  http = The destination for the connection.
1192  *          3  :  fwd  = The forwarder settings used.
1193  *          4  :  server_connection  = storage.
1194  *
1195  * Returns     : void
1196  *
1197  *********************************************************************/
1198 static void save_connection_destination(jb_socket sfd,
1199                                         const struct http_request *http,
1200                                         const struct forward_spec *fwd,
1201                                         struct reusable_connection *server_connection)
1202 {
1203    assert(sfd != JB_INVALID_SOCKET);
1204    assert(NULL != http->host);
1205
1206    server_connection->sfd = sfd;
1207    server_connection->host = strdup_or_die(http->host);
1208    server_connection->port = http->port;
1209
1210    assert(NULL != fwd);
1211    assert(server_connection->gateway_host == NULL);
1212    assert(server_connection->gateway_port == 0);
1213    assert(server_connection->forwarder_type == 0);
1214    assert(server_connection->forward_host == NULL);
1215    assert(server_connection->forward_port == 0);
1216
1217    server_connection->forwarder_type = fwd->type;
1218    if (NULL != fwd->gateway_host)
1219    {
1220       server_connection->gateway_host = strdup_or_die(fwd->gateway_host);
1221    }
1222    else
1223    {
1224       server_connection->gateway_host = NULL;
1225    }
1226    server_connection->gateway_port = fwd->gateway_port;
1227    if (NULL != fwd->auth_username)
1228    {
1229       server_connection->auth_username = strdup_or_die(fwd->auth_username);
1230    }
1231    else
1232    {
1233       server_connection->auth_username = NULL;
1234    }
1235    if (NULL != fwd->auth_password)
1236    {
1237       server_connection->auth_password = strdup_or_die(fwd->auth_password);
1238    }
1239    else
1240    {
1241       server_connection->auth_password = NULL;
1242    }
1243
1244    if (NULL != fwd->forward_host)
1245    {
1246       server_connection->forward_host = strdup_or_die(fwd->forward_host);
1247    }
1248    else
1249    {
1250       server_connection->forward_host = NULL;
1251    }
1252    server_connection->forward_port = fwd->forward_port;
1253 }
1254 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1255
1256
1257 /*********************************************************************
1258  *
1259  * Function    : verify_request_length
1260  *
1261  * Description : Checks if we already got the whole client requests
1262  *               and sets CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ if
1263  *               we do.
1264  *
1265  *               Data that doesn't belong to the current request is
1266  *               either thrown away to let the client retry on a clean
1267  *               socket, or stashed to be dealt with after the current
1268  *               request is served.
1269  *
1270  * Parameters  :
1271  *          1  :  csp = Current client state (buffers, headers, etc...)
1272  *
1273  * Returns     :  void
1274  *
1275  *********************************************************************/
1276 static void verify_request_length(struct client_state *csp)
1277 {
1278    unsigned long long buffered_request_bytes =
1279       (unsigned long long)(csp->client_iob->eod - csp->client_iob->cur);
1280
1281    if ((csp->expected_client_content_length != 0)
1282       && (buffered_request_bytes != 0))
1283    {
1284       if (csp->expected_client_content_length >= buffered_request_bytes)
1285       {
1286          csp->expected_client_content_length -= buffered_request_bytes;
1287          log_error(LOG_LEVEL_CONNECT, "Reduced expected bytes to %llu "
1288             "to account for the %llu ones we already got.",
1289             csp->expected_client_content_length, buffered_request_bytes);
1290       }
1291       else
1292       {
1293          assert(csp->client_iob->eod > csp->client_iob->cur + csp->expected_client_content_length);
1294          csp->client_iob->eod = csp->client_iob->cur + csp->expected_client_content_length;
1295          log_error(LOG_LEVEL_CONNECT, "Reducing expected bytes to 0. "
1296             "Marking the server socket tainted after throwing %llu bytes away.",
1297             buffered_request_bytes - csp->expected_client_content_length);
1298          csp->expected_client_content_length = 0;
1299          csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1300       }
1301
1302       if (csp->expected_client_content_length == 0)
1303       {
1304          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1305       }
1306    }
1307
1308    if (!(csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ)
1309       && ((csp->client_iob->cur < csp->client_iob->eod)
1310          || (csp->expected_client_content_length != 0)))
1311    {
1312       if (strcmpic(csp->http->gpc, "GET")
1313          && strcmpic(csp->http->gpc, "HEAD")
1314          && strcmpic(csp->http->gpc, "TRACE")
1315          && strcmpic(csp->http->gpc, "OPTIONS")
1316          && strcmpic(csp->http->gpc, "DELETE"))
1317       {
1318          /* XXX: this is an incomplete hack */
1319          csp->flags &= ~CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1320          log_error(LOG_LEVEL_CONNECT, "There better be a request body.");
1321       }
1322       else
1323       {
1324          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1325
1326          if ((csp->config->feature_flags & RUNTIME_FEATURE_TOLERATE_PIPELINING) == 0)
1327          {
1328             csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1329             log_error(LOG_LEVEL_CONNECT,
1330                "Possible pipeline attempt detected. The connection will not "
1331                "be kept alive and we will only serve the first request.");
1332             /* Nuke the pipelined requests from orbit, just to be sure. */
1333             clear_iob(csp->client_iob);
1334          }
1335          else
1336          {
1337             /*
1338              * Keep the pipelined data around for now, we'll deal with
1339              * it once we're done serving the current request.
1340              */
1341             csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
1342             assert(csp->client_iob->eod >= csp->client_iob->cur);
1343             log_error(LOG_LEVEL_CONNECT, "Complete client request followed by "
1344                "%d bytes of pipelined data received.",
1345                (int)(csp->client_iob->eod - csp->client_iob->cur));
1346          }
1347       }
1348    }
1349    else
1350    {
1351       csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1352       log_error(LOG_LEVEL_CONNECT, "Complete client request received.");
1353    }
1354 }
1355
1356
1357 /*********************************************************************
1358  *
1359  * Function    :  mark_server_socket_tainted
1360  *
1361  * Description :  Makes sure we don't reuse a server socket
1362  *                (if we didn't read everything the server sent
1363  *                us reusing the socket would lead to garbage).
1364  *
1365  * Parameters  :
1366  *          1  :  csp = Current client state (buffers, headers, etc...)
1367  *
1368  * Returns     :  void.
1369  *
1370  *********************************************************************/
1371 static void mark_server_socket_tainted(struct client_state *csp)
1372 {
1373    /*
1374     * For consistency we always mark the server socket
1375     * tainted, however, to reduce the log noise we only
1376     * emit a log message if the server socket could have
1377     * actually been reused.
1378     */
1379    if ((csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE)
1380       && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
1381    {
1382       log_error(LOG_LEVEL_CONNECT,
1383          "Marking the server socket %d tainted.",
1384          csp->server_connection.sfd);
1385    }
1386    csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1387 }
1388
1389 /*********************************************************************
1390  *
1391  * Function    :  get_request_line
1392  *
1393  * Description : Read the client request line.
1394  *
1395  * Parameters  :
1396  *          1  :  csp = Current client state (buffers, headers, etc...)
1397  *
1398  * Returns     :  Pointer to request line or NULL in case of errors.
1399  *
1400  *********************************************************************/
1401 static char *get_request_line(struct client_state *csp)
1402 {
1403    char buf[BUFFER_SIZE];
1404    char *request_line = NULL;
1405    int len;
1406
1407    memset(buf, 0, sizeof(buf));
1408
1409    if ((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) != 0)
1410    {
1411       /*
1412        * If there are multiple pipelined requests waiting,
1413        * the flag will be set again once the next request
1414        * has been parsed.
1415        */
1416       csp->flags &= ~CSP_FLAG_PIPELINED_REQUEST_WAITING;
1417
1418       request_line = get_header(csp->client_iob);
1419       if ((NULL != request_line) && ('\0' != *request_line))
1420       {
1421          return request_line;
1422       }
1423       else
1424       {
1425          log_error(LOG_LEVEL_CONNECT, "No complete request line "
1426             "received yet. Continuing reading from %d.", csp->cfd);
1427       }
1428    }
1429
1430    do
1431    {
1432       if (
1433 #ifdef FUZZ
1434           0 == (csp->flags & CSP_FLAG_FUZZED_INPUT) &&
1435 #endif
1436           !data_is_available(csp->cfd, csp->config->socket_timeout)
1437           )
1438       {
1439          if (socket_is_still_alive(csp->cfd))
1440          {
1441             log_error(LOG_LEVEL_CONNECT,
1442                "No request line on socket %d received in time. Timeout: %d.",
1443                csp->cfd, csp->config->socket_timeout);
1444             write_socket_delayed(csp->cfd, CLIENT_CONNECTION_TIMEOUT_RESPONSE,
1445                strlen(CLIENT_CONNECTION_TIMEOUT_RESPONSE),
1446                get_write_delay(csp));
1447          }
1448          else
1449          {
1450             log_error(LOG_LEVEL_CONNECT,
1451                "The client side of the connection on socket %d got "
1452                "closed without sending a complete request line.", csp->cfd);
1453          }
1454          return NULL;
1455       }
1456
1457       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1458
1459       if (len <= 0) return NULL;
1460
1461       /*
1462        * If there is no memory left for buffering the
1463        * request, there is nothing we can do but hang up
1464        */
1465       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1466       {
1467          return NULL;
1468       }
1469
1470       request_line = get_header(csp->client_iob);
1471
1472    } while ((NULL != request_line) && ('\0' == *request_line));
1473
1474    return request_line;
1475
1476 }
1477
1478 enum chunk_status
1479 {
1480    CHUNK_STATUS_MISSING_DATA,
1481    CHUNK_STATUS_BODY_COMPLETE,
1482    CHUNK_STATUS_PARSE_ERROR
1483 };
1484
1485
1486 /*********************************************************************
1487  *
1488  * Function    :  chunked_body_is_complete
1489  *
1490  * Description :  Figures out whether or not a chunked body is complete.
1491  *
1492  *                Currently it always starts at the beginning of the
1493  *                buffer which is somewhat wasteful and prevents Privoxy
1494  *                from starting to forward the correctly parsed chunks
1495  *                as soon as theoretically possible.
1496  *
1497  *                Should be modified to work with a common buffer,
1498  *                and allow the caller to skip already parsed chunks.
1499  *
1500  *                This would allow the function to be used for unbuffered
1501  *                response bodies as well.
1502  *
1503  * Parameters  :
1504  *          1  :  iob = Buffer with the body to check.
1505  *          2  :  length = Length of complete body
1506  *
1507  * Returns     :  Enum with the result of the check.
1508  *
1509  *********************************************************************/
1510 static enum chunk_status chunked_body_is_complete(struct iob *iob, size_t *length)
1511 {
1512    unsigned int chunksize;
1513    char *p = iob->cur;
1514
1515    do
1516    {
1517       /*
1518        * We need at least a single digit, followed by "\r\n",
1519        * followed by an unknown amount of data, followed by "\r\n".
1520        */
1521       if (p + 5 > iob->eod)
1522       {
1523          return CHUNK_STATUS_MISSING_DATA;
1524       }
1525       if (sscanf(p, "%x", &chunksize) != 1)
1526       {
1527          return CHUNK_STATUS_PARSE_ERROR;
1528       }
1529
1530       /*
1531        * We want at least a single digit, followed by "\r\n",
1532        * followed by the specified amount of data, followed by "\r\n".
1533        */
1534       if (p + chunksize + 5 > iob->eod)
1535       {
1536          return CHUNK_STATUS_MISSING_DATA;
1537       }
1538
1539       /* Skip chunk-size. */
1540       p = strstr(p, "\r\n");
1541       if (NULL == p)
1542       {
1543          return CHUNK_STATUS_PARSE_ERROR;
1544       }
1545       /* Move beyond the chunkdata. */
1546       p += 2 + chunksize;
1547
1548       /* Make sure we're still within the buffer and have two bytes left */
1549       if (p + 2 > iob->eod)
1550       {
1551          return CHUNK_STATUS_MISSING_DATA;
1552       }
1553
1554       /* There should be another "\r\n" to skip */
1555       if (memcmp(p, "\r\n", 2))
1556       {
1557          return CHUNK_STATUS_PARSE_ERROR;
1558       }
1559       p += 2;
1560    } while (chunksize > 0U);
1561
1562    *length = (size_t)(p - iob->cur);
1563    assert(*length <= (size_t)(iob->eod - iob->cur));
1564    assert(p <= iob->eod);
1565
1566    return CHUNK_STATUS_BODY_COMPLETE;
1567
1568 }
1569
1570
1571 /*********************************************************************
1572  *
1573  * Function    : receive_chunked_client_request_body
1574  *
1575  * Description : Read the chunk-encoded client request body.
1576  *               Failures are dealt with.
1577  *
1578  * Parameters  :
1579  *          1  :  csp = Current client state (buffers, headers, etc...)
1580  *
1581  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1582  *
1583  *********************************************************************/
1584 static jb_err receive_chunked_client_request_body(struct client_state *csp)
1585 {
1586    size_t body_length;
1587    enum chunk_status status;
1588
1589    while (CHUNK_STATUS_MISSING_DATA ==
1590       (status = chunked_body_is_complete(csp->client_iob, &body_length)))
1591    {
1592       char buf[BUFFER_SIZE];
1593       int len;
1594
1595       if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1596       {
1597          log_error(LOG_LEVEL_ERROR,
1598             "Timeout while waiting for the client body.");
1599          break;
1600       }
1601       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1602       if (len <= 0)
1603       {
1604          log_error(LOG_LEVEL_ERROR,
1605             "Reading the client body failed: %E");
1606          break;
1607       }
1608       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1609       {
1610          break;
1611       }
1612    }
1613    if (status != CHUNK_STATUS_BODY_COMPLETE)
1614    {
1615       write_socket_delayed(csp->cfd, CLIENT_BODY_PARSE_ERROR_RESPONSE,
1616          strlen(CLIENT_BODY_PARSE_ERROR_RESPONSE), get_write_delay(csp));
1617       log_error(LOG_LEVEL_CLF,
1618          "%s - - [%T] \"Failed reading chunked client body\" 400 0", csp->ip_addr_str);
1619       return JB_ERR_PARSE;
1620    }
1621    log_error(LOG_LEVEL_CONNECT,
1622       "Chunked client body completely read. Length: %lu", body_length);
1623    csp->expected_client_content_length = body_length;
1624
1625    return JB_ERR_OK;
1626
1627 }
1628
1629
1630 #ifdef FUZZ
1631 /*********************************************************************
1632  *
1633  * Function    :  fuzz_chunked_transfer_encoding
1634  *
1635  * Description :  Treat the fuzzed input as chunked transfer encoding
1636  *                to check and dechunk.
1637  *
1638  * Parameters  :
1639  *          1  :  csp      = Used to store the data.
1640  *          2  :  fuzz_input_file = File to read the input from.
1641  *
1642  * Returns     : Result of dechunking
1643  *
1644  *********************************************************************/
1645 extern int fuzz_chunked_transfer_encoding(struct client_state *csp, char *fuzz_input_file)
1646 {
1647    size_t length;
1648    size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
1649    enum chunk_status status;
1650
1651    status = chunked_body_is_complete(csp->iob, &length);
1652    if (CHUNK_STATUS_BODY_COMPLETE != status)
1653    {
1654       log_error(LOG_LEVEL_INFO, "Chunked body is incomplete or invalid");
1655    }
1656    if (get_bytes_missing_from_chunked_data(csp->iob->cur, size, 0) == 0)
1657    {
1658       if (CHUNK_STATUS_BODY_COMPLETE != status)
1659       {
1660          log_error(LOG_LEVEL_ERROR,
1661             "There's disagreement about whether or not the chunked body is complete.");
1662       }
1663    }
1664
1665    return (JB_ERR_OK == remove_chunked_transfer_coding(csp->iob->cur, &size));
1666
1667 }
1668
1669
1670 /*********************************************************************
1671  *
1672  * Function    : fuzz_client_request
1673  *
1674  * Description : Try to get a client request from the fuzzed input.
1675  *
1676  * Parameters  :
1677  *          1  :  csp = Current client state (buffers, headers, etc...)
1678  *          2  :  fuzz_input_file = File to read the input from.
1679  *
1680  * Returns     :  Result of fuzzing.
1681  *
1682  *********************************************************************/
1683 extern int fuzz_client_request(struct client_state *csp, char *fuzz_input_file)
1684 {
1685    jb_err err;
1686
1687    csp->cfd = 0;
1688    csp->ip_addr_str = "fuzzer";
1689
1690    if (strcmp(fuzz_input_file, "-") != 0)
1691    {
1692       log_error(LOG_LEVEL_FATAL,
1693          "Fuzzed client requests can currently only be read from stdin (-).");
1694    }
1695    err = receive_client_request(csp);
1696    if (err != JB_ERR_OK)
1697    {
1698       return 1;
1699    }
1700    err = parse_client_request(csp);
1701    if (err != JB_ERR_OK)
1702    {
1703       return 1;
1704    }
1705
1706    return 0;
1707
1708 }
1709 #endif  /* def FUZZ */
1710
1711
1712 #ifdef FEATURE_FORCE_LOAD
1713 /*********************************************************************
1714  *
1715  * Function    :  force_required
1716  *
1717  * Description : Checks a request line to see if it contains
1718  *               the FORCE_PREFIX. If it does, it is removed
1719  *               unless enforcing requests has beend disabled.
1720  *
1721  * Parameters  :
1722  *          1  :  request_line = HTTP request line
1723  *
1724  * Returns     :  TRUE if force is required, FALSE otherwise.
1725  *
1726  *********************************************************************/
1727 static int force_required(const struct client_state *csp, char *request_line)
1728 {
1729    char *p;
1730
1731    p = strstr(request_line, "http://");
1732    if (p != NULL)
1733    {
1734       /* Skip protocol */
1735       p += strlen("http://");
1736    }
1737    else
1738    {
1739       /* Intercepted request usually don't specify the protocol. */
1740       p = request_line;
1741    }
1742
1743    /* Go to the beginning of the path */
1744    p = strstr(p, "/");
1745    if (p == NULL)
1746    {
1747       /*
1748        * If the path is missing the request line is invalid and we
1749        * are done here. The client-visible rejection happens later on.
1750        */
1751       return 0;
1752    }
1753
1754    if (0 == strncmpic(p, FORCE_PREFIX, strlen(FORCE_PREFIX) - 1))
1755    {
1756       if (!(csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS))
1757       {
1758          /* XXX: Should clean more carefully */
1759          strclean(request_line, FORCE_PREFIX);
1760          log_error(LOG_LEVEL_FORCE,
1761             "Enforcing request: \"%s\".", request_line);
1762
1763          return 1;
1764       }
1765       log_error(LOG_LEVEL_FORCE,
1766          "Ignored force prefix in request: \"%s\".", request_line);
1767    }
1768
1769    return 0;
1770
1771 }
1772 #endif /* def FEATURE_FORCE_LOAD */
1773
1774
1775 /*********************************************************************
1776  *
1777  * Function    :  receive_client_request
1778  *
1779  * Description : Read the client's request (more precisely the
1780  *               client headers) and answer it if necessary.
1781  *
1782  * Parameters  :
1783  *          1  :  csp = Current client state (buffers, headers, etc...)
1784  *
1785  * Returns     :  JB_ERR_OK, JB_ERR_PARSE or JB_ERR_MEMORY
1786  *
1787  *********************************************************************/
1788 static jb_err receive_client_request(struct client_state *csp)
1789 {
1790    char buf[BUFFER_SIZE];
1791    char *p;
1792    char *req = NULL;
1793    struct http_request *http;
1794    int len;
1795    jb_err err;
1796
1797    /* Temporary copy of the client's headers before they get enlisted in csp->headers */
1798    struct list header_list;
1799    struct list *headers = &header_list;
1800
1801    /* We don't care if the arriving data is a valid HTTP request or not. */
1802    csp->requests_received_total++;
1803
1804    http = csp->http;
1805
1806    memset(buf, 0, sizeof(buf));
1807
1808    req = get_request_line(csp);
1809    if (req == NULL)
1810    {
1811       mark_server_socket_tainted(csp);
1812       return JB_ERR_PARSE;
1813    }
1814    assert(*req != '\0');
1815
1816    if (client_protocol_is_unsupported(csp, req))
1817    {
1818       return JB_ERR_PARSE;
1819    }
1820
1821 #ifdef FEATURE_FORCE_LOAD
1822    if (force_required(csp, req))
1823    {
1824       csp->flags |= CSP_FLAG_FORCED;
1825    }
1826 #endif /* def FEATURE_FORCE_LOAD */
1827
1828    err = parse_http_request(req, http);
1829    freez(req);
1830    if (JB_ERR_OK != err)
1831    {
1832       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
1833          get_write_delay(csp));
1834       /* XXX: Use correct size */
1835       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
1836       log_error(LOG_LEVEL_ERROR,
1837          "Couldn't parse request line received from %s: %s",
1838          csp->ip_addr_str, jb_err_to_string(err));
1839
1840       free_http_request(http);
1841       return JB_ERR_PARSE;
1842    }
1843    if (http->ssl && strcmpic(http->gpc, "CONNECT"))
1844    {
1845       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
1846          get_write_delay(csp));
1847       /* XXX: Use correct size */
1848       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0",
1849          csp->ip_addr_str);
1850       log_error(LOG_LEVEL_ERROR, "Client %s tried to send a https "
1851          "URL without sending a CONNECT request first",
1852          csp->ip_addr_str);
1853       free_http_request(http);
1854       return JB_ERR_PARSE;
1855    }
1856
1857    /* grab the rest of the client's headers */
1858    init_list(headers);
1859    for (;;)
1860    {
1861       p = get_header(csp->client_iob);
1862
1863       if (p == NULL)
1864       {
1865          /* There are no additional headers to read. */
1866          break;
1867       }
1868
1869       if (*p == '\0')
1870       {
1871          /*
1872           * We didn't receive a complete header
1873           * line yet, get the rest of it.
1874           */
1875          if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1876          {
1877             log_error(LOG_LEVEL_ERROR,
1878                "Client headers did not arrive in time. Timeout: %d",
1879                csp->config->socket_timeout);
1880             destroy_list(headers);
1881             return JB_ERR_PARSE;
1882          }
1883
1884          len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1885          if (len <= 0)
1886          {
1887             log_error(LOG_LEVEL_ERROR, "read from client failed: %E");
1888             destroy_list(headers);
1889             return JB_ERR_PARSE;
1890          }
1891
1892          if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1893          {
1894             /*
1895              * If there is no memory left for buffering the
1896              * request, there is nothing we can do but hang up
1897              */
1898             destroy_list(headers);
1899             return JB_ERR_MEMORY;
1900          }
1901       }
1902       else
1903       {
1904          if (!strncmpic(p, "Transfer-Encoding:", 18))
1905          {
1906             /*
1907              * XXX: should be called through sed()
1908              *      but currently can't.
1909              */
1910             client_transfer_encoding(csp, &p);
1911          }
1912          /*
1913           * We were able to read a complete
1914           * header and can finally enlist it.
1915           */
1916          enlist(headers, p);
1917          freez(p);
1918       }
1919    }
1920
1921    if (http->host == NULL)
1922    {
1923       /*
1924        * If we still don't know the request destination,
1925        * the request is invalid or the client uses
1926        * Privoxy without its knowledge.
1927        */
1928       if (JB_ERR_OK != get_request_destination_elsewhere(csp, headers))
1929       {
1930          /*
1931           * Our attempts to get the request destination
1932           * elsewhere failed or Privoxy is configured
1933           * to only accept proxy requests.
1934           *
1935           * An error response has already been sent
1936           * and we're done here.
1937           */
1938          return JB_ERR_PARSE;
1939       }
1940    }
1941
1942 #ifdef FEATURE_CLIENT_TAGS
1943    /* XXX: If the headers were enlisted sooner, passing csp would do. */
1944    set_client_address(csp, headers);
1945    get_tag_list_for_client(csp->client_tags, csp->client_address);
1946 #endif
1947
1948    /*
1949     * Determine the actions for this URL
1950     */
1951 #ifdef FEATURE_TOGGLE
1952    if (!(csp->flags & CSP_FLAG_TOGGLED_ON))
1953    {
1954       /* Most compatible set of actions (i.e. none) */
1955       init_current_action(csp->action);
1956    }
1957    else
1958 #endif /* ndef FEATURE_TOGGLE */
1959    {
1960       get_url_actions(csp, http);
1961    }
1962
1963    enlist(csp->headers, http->cmd);
1964
1965    /* Append the previously read headers */
1966    err = list_append_list_unique(csp->headers, headers);
1967    destroy_list(headers);
1968
1969    return err;
1970
1971 }
1972
1973
1974 /*********************************************************************
1975  *
1976  * Function    : parse_client_request
1977  *
1978  * Description : Parses the client's request and decides what to do
1979  *               with it.
1980  *
1981  *               Note that since we're not using select() we could get
1982  *               blocked here if a client connected, then didn't say
1983  *               anything!
1984  *
1985  * Parameters  :
1986  *          1  :  csp = Current client state (buffers, headers, etc...)
1987  *
1988  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1989  *
1990  *********************************************************************/
1991 static jb_err parse_client_request(struct client_state *csp)
1992 {
1993    struct http_request *http = csp->http;
1994    jb_err err;
1995
1996 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1997    if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
1998     && (!strcmpic(csp->http->version, "HTTP/1.1"))
1999     && (csp->http->ssl == 0))
2000    {
2001       /* Assume persistence until further notice */
2002       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2003    }
2004 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2005
2006    if (csp->http->ssl == 0)
2007    {
2008       /*
2009        * This whole block belongs to chat() but currently
2010        * has to be executed before sed().
2011        */
2012       if (csp->flags & CSP_FLAG_CHUNKED_CLIENT_BODY)
2013       {
2014          if (receive_chunked_client_request_body(csp) != JB_ERR_OK)
2015          {
2016             return JB_ERR_PARSE;
2017          }
2018       }
2019       else
2020       {
2021          csp->expected_client_content_length = get_expected_content_length(csp->headers);
2022       }
2023       verify_request_length(csp);
2024    }
2025 #ifndef FEATURE_HTTPS_INSPECTION
2026    else
2027    {
2028       csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
2029    }
2030 #endif
2031
2032    err = sed(csp, FILTER_CLIENT_HEADERS);
2033    if (JB_ERR_OK != err)
2034    {
2035       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
2036          csp->ip_addr_str);
2037       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
2038          csp->ip_addr_str, csp->http->cmd);
2039       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER), get_write_delay(csp));
2040       return JB_ERR_PARSE;
2041    }
2042    csp->flags |= CSP_FLAG_CLIENT_HEADER_PARSING_DONE;
2043
2044    /* Check request line for rewrites. */
2045    if ((NULL == csp->headers->first->str)
2046       || (strcmp(http->cmd, csp->headers->first->str) &&
2047          (JB_ERR_OK != change_request_destination(csp))))
2048    {
2049       /*
2050        * A header filter broke the request line - bail out.
2051        */
2052       write_socket_delayed(csp->cfd, MESSED_UP_REQUEST_RESPONSE,
2053          strlen(MESSED_UP_REQUEST_RESPONSE), get_write_delay(csp));
2054       /* XXX: Use correct size */
2055       log_error(LOG_LEVEL_CLF,
2056          "%s - - [%T] \"Invalid request generated\" 400 0", csp->ip_addr_str);
2057       log_error(LOG_LEVEL_ERROR,
2058          "Invalid request line after applying header filters.");
2059       free_http_request(http);
2060
2061       return JB_ERR_PARSE;
2062    }
2063
2064    if (client_has_unsupported_expectations(csp))
2065    {
2066       return JB_ERR_PARSE;
2067    }
2068
2069    return JB_ERR_OK;
2070
2071 }
2072
2073
2074 /*********************************************************************
2075  *
2076  * Function    : read_http_request_body
2077  *
2078  * Description : Reads remaining request body from the client.
2079  *
2080  * Parameters  :
2081  *          1  :  csp = Current client state (buffers, headers, etc...)
2082  *
2083  * Returns     :  0 on success, anything else is an error.
2084  *
2085  *********************************************************************/
2086 static int read_http_request_body(struct client_state *csp)
2087 {
2088    size_t to_read = csp->expected_client_content_length;
2089    int len;
2090
2091    assert(to_read != 0);
2092
2093    /* check if all data has been already read */
2094    if (to_read <= (csp->client_iob->eod - csp->client_iob->cur))
2095    {
2096       return 0;
2097    }
2098
2099    for (to_read -= (size_t)(csp->client_iob->eod - csp->client_iob->cur);
2100         to_read > 0 && data_is_available(csp->cfd, csp->config->socket_timeout);
2101         to_read -= (unsigned)len)
2102    {
2103       char buf[BUFFER_SIZE];
2104       size_t max_bytes_to_read = to_read < sizeof(buf) ? to_read : sizeof(buf);
2105
2106       log_error(LOG_LEVEL_CONNECT,
2107          "Waiting for up to %lu bytes of request body from the client.",
2108          max_bytes_to_read);
2109       len = read_socket(csp->cfd, buf, (int)max_bytes_to_read);
2110       if (len <= -1)
2111       {
2112          log_error(LOG_LEVEL_CONNECT, "Failed receiving request body from %s: %E", csp->ip_addr_str);
2113          return 1;
2114       }
2115       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, (char *)buf, len))
2116       {
2117          return 1;
2118       }
2119       assert(to_read >= len);
2120    }
2121
2122    if (to_read != 0)
2123    {
2124       log_error(LOG_LEVEL_CONNECT,
2125          "Not enough request body has been read: expected %lu more bytes.",
2126          to_read);
2127       return 1;
2128    }
2129    log_error(LOG_LEVEL_CONNECT,
2130       "The last %d bytes of the request body have been read.", len);
2131    return 0;
2132 }
2133
2134
2135 /*********************************************************************
2136  *
2137  * Function    : update_client_headers
2138  *
2139  * Description : Updates the HTTP headers from the client request.
2140  *
2141  * Parameters  :
2142  *          1  :  csp = Current client state (buffers, headers, etc...)
2143  *          2  :  new_content_length = new content length value to set
2144  *
2145  * Returns     :  0 on success, anything else is an error.
2146  *
2147  *********************************************************************/
2148 static int update_client_headers(struct client_state *csp, size_t new_content_length)
2149 {
2150    static const char content_length[] = "Content-Length:";
2151    int updated = 0;
2152    struct list_entry *p;
2153
2154 #ifndef FEATURE_HTTPS_INSPECTION
2155    for (p = csp->headers->first;
2156 #else
2157    for (p = csp->http->client_ssl ? csp->https_headers->first : csp->headers->first;
2158 #endif
2159         !updated  && (p != NULL); p = p->next)
2160    {
2161       /* Header crunch()ed in previous run? -> ignore */
2162       if (p->str == NULL)
2163       {
2164          continue;
2165       }
2166
2167       /* Does the current parser handle this header? */
2168       if (0 == strncmpic(p->str, content_length, sizeof(content_length) - 1))
2169       {
2170          updated = (JB_ERR_OK == header_adjust_content_length((char **)&(p->str), new_content_length));
2171          if (!updated)
2172          {
2173             return 1;
2174          }
2175       }
2176    }
2177
2178    return !updated;
2179 }
2180
2181
2182 /*********************************************************************
2183  *
2184  * Function    : can_buffer_request_body
2185  *
2186  * Description : Checks if the current request body can be stored in
2187  *               the client_iob without hitting buffer limit.
2188  *
2189  * Parameters  :
2190  *          1  : csp = Current client state (buffers, headers, etc...)
2191  *
2192  * Returns     : TRUE if the current request size do not exceed buffer limit
2193  *               FALSE otherwise.
2194  *
2195  *********************************************************************/
2196 static int can_buffer_request_body(const struct client_state *csp)
2197 {
2198    if (!can_add_to_iob(csp->client_iob, csp->config->buffer_limit,
2199                        csp->expected_client_content_length))
2200    {
2201       log_error(LOG_LEVEL_INFO,
2202          "Not filtering request body from %s: buffer limit %lu will be exceeded "
2203          "(content length %llu)", csp->ip_addr_str, csp->config->buffer_limit,
2204          csp->expected_client_content_length);
2205       return FALSE;
2206    }
2207    return TRUE;
2208 }
2209
2210
2211 /*********************************************************************
2212  *
2213  * Function    : send_http_request
2214  *
2215  * Description : Sends the HTTP headers from the client request
2216  *               and all the body data that has already been received.
2217  *
2218  * Parameters  :
2219  *          1  :  csp = Current client state (buffers, headers, etc...)
2220  *
2221  * Returns     :  0 on success, 1 on error, 2 if the request got crunched.
2222  *
2223  *********************************************************************/
2224 static int send_http_request(struct client_state *csp)
2225 {
2226    char *hdr;
2227    int write_failure;
2228
2229    hdr = list_to_text(csp->headers);
2230    if (hdr == NULL)
2231    {
2232       /* FIXME Should handle error properly */
2233       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header");
2234    }
2235    list_remove_all(csp->headers);
2236
2237    /*
2238     * Write the client's (modified) header to the server
2239     * (along with anything else that may be in the buffer)
2240     */
2241    write_failure = 0 != write_socket(csp->server_connection.sfd, hdr, strlen(hdr));
2242    freez(hdr);
2243
2244    if (write_failure)
2245    {
2246       log_error(LOG_LEVEL_CONNECT, "Failed sending request headers to: %s: %E",
2247          csp->http->hostport);
2248       return 1;
2249    }
2250
2251    /* XXX: Filtered data is not sent if there's a pipelined request? */
2252    if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2253       && (flush_iob(csp->server_connection.sfd, csp->client_iob, 0) < 0))
2254    {
2255       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2256          csp->http->hostport);
2257       return 1;
2258    }
2259    return 0;
2260 }
2261
2262
2263 #ifdef FEATURE_HTTPS_INSPECTION
2264 /*********************************************************************
2265  *
2266  * Function    : read_https_request_body
2267  *
2268  * Description : Reads remaining request body from the client.
2269  *
2270  * Parameters  :
2271  *          1  :  csp = Current client state (buffers, headers, etc...)
2272  *
2273  * Returns     :  0 on success, anything else is an error.
2274  *
2275  *********************************************************************/
2276 static int read_https_request_body(struct client_state *csp)
2277 {
2278    size_t to_read = csp->expected_client_content_length;
2279    int len;
2280
2281    assert(to_read != 0);
2282
2283    /* check if all data has been already read */
2284    if (to_read <= (csp->client_iob->eod - csp->client_iob->cur))
2285    {
2286       return 0;
2287    }
2288
2289    for (to_read -= (size_t)(csp->client_iob->eod - csp->client_iob->cur);
2290         to_read > 0 && (is_ssl_pending(&(csp->ssl_client_attr)) ||
2291           data_is_available(csp->cfd, csp->config->socket_timeout));
2292         to_read -= (unsigned)len)
2293    {
2294       unsigned char buf[BUFFER_SIZE];
2295       size_t max_bytes_to_read = to_read < sizeof(buf) ? to_read : sizeof(buf);
2296
2297       log_error(LOG_LEVEL_CONNECT,
2298          "Buffering encrypted client body. Prepared to read up to %lu bytes.",
2299          max_bytes_to_read);
2300       len = ssl_recv_data(&(csp->ssl_client_attr), buf,
2301          (unsigned)max_bytes_to_read);
2302       if (len <= 0)
2303       {
2304          log_error(LOG_LEVEL_CONNECT,
2305             "Did not receive the whole encrypted request body from %s.",
2306             csp->ip_addr_str);
2307          return 1;
2308       }
2309       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, (char *)buf, len))
2310       {
2311          return 1;
2312       }
2313       assert(to_read >= len);
2314    }
2315
2316    if (to_read != 0)
2317    {
2318       log_error(LOG_LEVEL_CONNECT,
2319          "Not enough encrypted request body has been read: expected %lu more bytes.",
2320          to_read);
2321       return 1;
2322    }
2323
2324    log_error(LOG_LEVEL_CONNECT,
2325       "The last %llu bytes of the encrypted request body have been read.",
2326       csp->expected_client_content_length);
2327    return 0;
2328 }
2329
2330
2331 /*********************************************************************
2332  *
2333  * Function    : receive_and_send_encrypted_post_data
2334  *
2335  * Description : Reads remaining request body from the client and sends
2336  *               it to the server.
2337  *
2338  * Parameters  :
2339  *          1  :  csp = Current client state (buffers, headers, etc...)
2340  *
2341  * Returns     :  0 on success, anything else is an error.
2342  *
2343  *********************************************************************/
2344 static int receive_and_send_encrypted_post_data(struct client_state *csp)
2345 {
2346    int content_length_known = csp->expected_client_content_length != 0;
2347
2348    while ((content_length_known && csp->expected_client_content_length != 0) ||
2349       (is_ssl_pending(&(csp->ssl_client_attr)) ||
2350             data_is_available(csp->cfd, csp->config->socket_timeout)))
2351    {
2352       unsigned char buf[BUFFER_SIZE];
2353       int len;
2354       int max_bytes_to_read = sizeof(buf);
2355
2356       if (content_length_known && csp->expected_client_content_length < sizeof(buf))
2357       {
2358          max_bytes_to_read = (int)csp->expected_client_content_length;
2359       }
2360       log_error(LOG_LEVEL_CONNECT,
2361          "Prepared to read up to %d bytes of encrypted request body from the client.",
2362          max_bytes_to_read);
2363       len = ssl_recv_data(&(csp->ssl_client_attr), buf,
2364          (unsigned)max_bytes_to_read);
2365       if (len == -1)
2366       {
2367          return 1;
2368       }
2369       if (len == 0)
2370       {
2371          /* XXX: Does this actually happen? */
2372          break;
2373       }
2374       log_error(LOG_LEVEL_CONNECT, "Forwarding %d bytes of encrypted request body.",
2375          len);
2376       len = ssl_send_data(&(csp->ssl_server_attr), buf, (size_t)len);
2377       if (len == -1)
2378       {
2379          return 1;
2380       }
2381       if (csp->expected_client_content_length != 0)
2382       {
2383          if (csp->expected_client_content_length >= len)
2384          {
2385             csp->expected_client_content_length -= (unsigned)len;
2386          }
2387          if (csp->expected_client_content_length == 0)
2388          {
2389             log_error(LOG_LEVEL_CONNECT, "Forwarded the last %d bytes.", len);
2390             break;
2391          }
2392       }
2393    }
2394
2395    log_error(LOG_LEVEL_CONNECT, "Done forwarding encrypted request body.");
2396
2397    return 0;
2398
2399 }
2400
2401
2402 /*********************************************************************
2403  *
2404  * Function    : send_https_request
2405  *
2406  * Description : Sends the HTTP headers from the client request
2407  *               and all the body data that has already been received.
2408  *
2409  * Parameters  :
2410  *          1  :  csp = Current client state (buffers, headers, etc...)
2411  *
2412  * Returns     :  0 on success, anything else is an error.
2413  *
2414  *********************************************************************/
2415 static int send_https_request(struct client_state *csp)
2416 {
2417    char *hdr;
2418    int ret;
2419    long flushed = 0;
2420
2421    hdr = list_to_text(csp->https_headers);
2422    if (hdr == NULL)
2423    {
2424       /* FIXME Should handle error properly */
2425       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header.");
2426    }
2427    list_remove_all(csp->https_headers);
2428
2429    /*
2430     * Write the client's (modified) header to the server
2431     * (along with anything else that may be in the buffer)
2432     */
2433    ret = ssl_send_data(&(csp->ssl_server_attr),
2434       (const unsigned char *)hdr, strlen(hdr));
2435    freez(hdr);
2436
2437    if (ret < 0)
2438    {
2439       log_error(LOG_LEVEL_CONNECT,
2440          "Failed sending encrypted request headers to: %s: %E",
2441          csp->http->hostport);
2442       mark_server_socket_tainted(csp);
2443       return 1;
2444    }
2445
2446    /* XXX: Client body isn't sent if there's pipelined data? */
2447    if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2448       && ((flushed = ssl_flush_socket(&(csp->ssl_server_attr),
2449             csp->client_iob)) < 0))
2450    {
2451       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2452          csp->http->hostport);
2453       return 1;
2454    }
2455    if (flushed != 0 || csp->expected_client_content_length != 0)
2456    {
2457       if (csp->expected_client_content_length != 0)
2458       {
2459          if (csp->expected_client_content_length < flushed)
2460          {
2461             log_error(LOG_LEVEL_ERROR,
2462                "Flushed %ld bytes of request body while only expecting %llu.",
2463                flushed, csp->expected_client_content_length);
2464             csp->expected_client_content_length = 0;
2465          }
2466          else
2467          {
2468             log_error(LOG_LEVEL_CONNECT,
2469                "Flushed %ld bytes of request body while expecting %llu.",
2470                flushed, csp->expected_client_content_length);
2471             csp->expected_client_content_length -= (unsigned)flushed;
2472             if (receive_and_send_encrypted_post_data(csp))
2473             {
2474                return 1;
2475             }
2476          }
2477       }
2478       else
2479       {
2480          log_error(LOG_LEVEL_CONNECT,
2481             "Flushed %ld bytes of request body.", flushed);
2482       }
2483    }
2484
2485    log_error(LOG_LEVEL_CONNECT, "Encrypted request sent.");
2486
2487    return 0;
2488
2489 }
2490
2491
2492 /*********************************************************************
2493  *
2494  * Function    :  receive_encrypted_request_headers
2495  *
2496  * Description :  Receives the encrypted request headers when
2497  *                https-inspecting.
2498  *
2499  * Parameters  :
2500  *          1  :  csp = Current client state (buffers, headers, etc...)
2501  *
2502  * Returns     :  JB_ERR_OK on success,
2503  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2504  *
2505  *********************************************************************/
2506 static jb_err receive_encrypted_request_headers(struct client_state *csp)
2507 {
2508    char buf[BUFFER_SIZE];
2509    int len;
2510    char *p;
2511
2512    do
2513    {
2514       log_error(LOG_LEVEL_HEADER, "Waiting for encrypted client headers");
2515       if (!is_ssl_pending(&(csp->ssl_client_attr)) &&
2516           !data_is_available(csp->cfd, csp->config->socket_timeout))
2517       {
2518          log_error(LOG_LEVEL_CONNECT,
2519             "Socket %d timed out while waiting for client headers", csp->cfd);
2520          return JB_ERR_PARSE;
2521       }
2522       len = ssl_recv_data(&(csp->ssl_client_attr),
2523          (unsigned char *)buf, sizeof(buf));
2524       if (len == 0)
2525       {
2526          log_error(LOG_LEVEL_CONNECT,
2527             "Socket %d closed while waiting for client headers", csp->cfd);
2528          return JB_ERR_PARSE;
2529       }
2530       if (len == -1)
2531       {
2532          return JB_ERR_PARSE;
2533       }
2534       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
2535       {
2536          return JB_ERR_MEMORY;
2537       }
2538       p = strstr(csp->client_iob->cur, "\r\n\r\n");
2539    } while (p == NULL);
2540
2541    log_error(LOG_LEVEL_HEADER, "Encrypted headers received completely");
2542
2543    return JB_ERR_OK;
2544 }
2545
2546
2547 /*********************************************************************
2548  *
2549  * Function    :  change_encrypted_request_destination
2550  *
2551  * Description :  Parse a (rewritten) request line from an encrypted
2552  *                request and regenerate the http request data.
2553  *
2554  * Parameters  :
2555  *          1  :  csp = Current client state (buffers, headers, etc...)
2556  *
2557  * Returns     :  Forwards the parse_http_request() return code.
2558  *                Terminates in case of memory problems.
2559  *
2560  *********************************************************************/
2561 static jb_err change_encrypted_request_destination(struct client_state *csp)
2562 {
2563    jb_err err;
2564    char *original_host = csp->http->host;
2565    int original_port = csp->http->port;
2566
2567    log_error(LOG_LEVEL_REDIRECTS, "Rewrite detected: %s",
2568       csp->https_headers->first->str);
2569    csp->http->host = NULL;
2570    free_http_request(csp->http);
2571    err = parse_http_request(csp->https_headers->first->str, csp->http);
2572    if (JB_ERR_OK != err)
2573    {
2574       log_error(LOG_LEVEL_ERROR, "Couldn't parse rewritten request: %s.",
2575          jb_err_to_string(err));
2576       freez(original_host);
2577       return err;
2578    }
2579
2580    if (csp->http->host == NULL)
2581    {
2582       char port_string[10];
2583       /*
2584        * The rewritten request line did not specify a host
2585        * which means we can use the original host specified
2586        * by the client.
2587        */
2588       csp->http->host = original_host;
2589       csp->http->port = original_port;
2590       log_error(LOG_LEVEL_REDIRECTS, "Keeping the original host: %s",
2591          csp->http->host);
2592       /*
2593        * If the rewritten request line didn't contain a host
2594        * it also didn't contain a port so we can reuse the host
2595        * port.
2596        */
2597       freez(csp->http->hostport);
2598       csp->http->hostport = strdup_or_die(csp->http->host);
2599       snprintf(port_string, sizeof(port_string), ":%d", original_port);
2600       err = string_append(&csp->http->hostport, port_string);
2601       if (err != JB_ERR_OK)
2602       {
2603          log_error(LOG_LEVEL_ERROR, "Failed to rebuild hostport: %s.",
2604             jb_err_to_string(err));
2605          return err;
2606       }
2607
2608       /*
2609        * While the request line didn't mention it,
2610        * we're https-inspecting and want to speak TLS
2611        * with the server.
2612        */
2613       csp->http->server_ssl = 1;
2614       csp->http->ssl = 1;
2615    }
2616    else
2617    {
2618       /* The rewrite filter added a host so we can ditch the original */
2619       freez(original_host);
2620       csp->http->server_ssl = csp->http->ssl;
2621    }
2622
2623    csp->http->client_ssl = 1;
2624
2625    freez(csp->https_headers->first->str);
2626    build_request_line(csp, NULL, &csp->https_headers->first->str);
2627
2628    if (!server_use_ssl(csp))
2629    {
2630       log_error(LOG_LEVEL_REDIRECTS,
2631          "Rewritten request line results in downgrade to http");
2632       /*
2633        * Replace the unencryptd headers received with the
2634        * CONNECT request with the ones we received securely.
2635        */
2636       destroy_list(csp->headers);
2637       csp->headers->first = csp->https_headers->first;
2638       csp->headers->last  = csp->https_headers->last;
2639       csp->https_headers->first = NULL;
2640       csp->https_headers->last = NULL;
2641    }
2642
2643    return JB_ERR_OK;
2644
2645 }
2646
2647
2648 /*********************************************************************
2649  *
2650  * Function    :  process_encrypted_request_headers
2651  *
2652  * Description :  Receives and parses the encrypted headers send
2653  *                by the client when https-inspecting.
2654  *
2655  * Parameters  :
2656  *          1  :  csp = Current client state (buffers, headers, etc...)
2657  *
2658  * Returns     :  JB_ERR_OK on success,
2659  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2660  *
2661  *********************************************************************/
2662 static jb_err process_encrypted_request_headers(struct client_state *csp)
2663 {
2664    char *p;
2665    char *request_line;
2666    jb_err err;
2667    /* Temporary copy of the client's headers before they get enlisted in csp->https_headers */
2668    struct list header_list;
2669    struct list *headers = &header_list;
2670
2671    assert(csp->ssl_with_client_is_opened);
2672
2673 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2674    if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
2675    {
2676       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2677    }
2678 #endif
2679    err = receive_encrypted_request_headers(csp);
2680    if (err != JB_ERR_OK)
2681    {
2682       if (csp->client_iob->cur == NULL ||
2683           csp->client_iob->cur == csp->client_iob->eod)
2684       {
2685          /*
2686           * We did not receive any data, most likely because the
2687           * client is done. Don't log this as a parse failure.
2688           */
2689          return JB_ERR_PARSE;
2690       }
2691       /* XXX: Also used for JB_ERR_MEMORY */
2692       log_error(LOG_LEVEL_ERROR, "Failed to receive encrypted request: %s",
2693          jb_err_to_string(err));
2694       ssl_send_data_delayed(&(csp->ssl_client_attr),
2695          (const unsigned char *)CHEADER, strlen(CHEADER), get_write_delay(csp));
2696       return err;
2697    }
2698
2699    /* We don't need get_request_line() because the whole HTTP head is buffered. */
2700    request_line = get_header(csp->client_iob);
2701    if (request_line == NULL)
2702    {
2703       log_error(LOG_LEVEL_ERROR, "Failed to get the encrypted request line");
2704       ssl_send_data_delayed(&(csp->ssl_client_attr),
2705          (const unsigned char *)CHEADER, strlen(CHEADER), get_write_delay(csp));
2706       return JB_ERR_PARSE;
2707    }
2708    assert(*request_line != '\0');
2709
2710    if (client_protocol_is_unsupported(csp, request_line))
2711    {
2712       /*
2713        * If the protocol is unsupported we're done here.
2714        * client_protocol_is_unsupported() took care of sending
2715        * the error response and logging the error message.
2716        */
2717       return JB_ERR_PARSE;
2718    }
2719
2720 #ifdef FEATURE_FORCE_LOAD
2721    if (force_required(csp, request_line))
2722    {
2723       csp->flags |= CSP_FLAG_FORCED;
2724    }
2725 #endif /* def FEATURE_FORCE_LOAD */
2726
2727    free_http_request(csp->http);
2728
2729    err = parse_http_request(request_line, csp->http);
2730    /* XXX: Restore ssl setting. This is ugly */
2731    csp->http->client_ssl = 1;
2732    csp->http->server_ssl = 1;
2733
2734    freez(request_line);
2735    if (JB_ERR_OK != err)
2736    {
2737       ssl_send_data_delayed(&(csp->ssl_client_attr),
2738          (const unsigned char *)CHEADER, strlen(CHEADER), get_write_delay(csp));
2739       /* XXX: Use correct size */
2740       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
2741       log_error(LOG_LEVEL_ERROR,
2742          "Couldn't parse request line received from %s: %s",
2743          csp->ip_addr_str, jb_err_to_string(err));
2744
2745       free_http_request(csp->http);
2746       return JB_ERR_PARSE;
2747    }
2748
2749    /* Parse the rest of the client's headers. */
2750    init_list(headers);
2751    for (;;)
2752    {
2753       p = get_header(csp->client_iob);
2754
2755       if (p == NULL)
2756       {
2757          /* There are no additional headers to read. */
2758          break;
2759       }
2760       enlist(headers, p);
2761       freez(p);
2762    }
2763
2764    if (JB_ERR_OK != get_destination_from_https_headers(headers, csp->http))
2765    {
2766       /*
2767        * Our attempts to get the request destination
2768        * elsewhere failed.
2769        */
2770       log_error(LOG_LEVEL_ERROR,
2771          "Failed to get the encrypted request destination");
2772       ssl_send_data_delayed(&(csp->ssl_client_attr),
2773          (const unsigned char *)CHEADER, strlen(CHEADER), get_write_delay(csp));
2774       destroy_list(headers);
2775
2776       return JB_ERR_PARSE;
2777    }
2778
2779    /* Split the domain we just got for pattern matching */
2780    init_domain_components(csp->http);
2781
2782 #ifdef FEATURE_CLIENT_TAGS
2783    /* XXX: If the headers were enlisted sooner, passing csp would do. */
2784    if (csp->client_address == NULL)
2785    {
2786       set_client_address(csp, headers);
2787       get_tag_list_for_client(csp->client_tags, csp->client_address);
2788    }
2789 #endif
2790
2791 #ifdef FEATURE_TOGGLE
2792    if ((csp->flags & CSP_FLAG_TOGGLED_ON) != 0)
2793 #endif
2794    {
2795       /*
2796        * Determine the actions for this request after
2797        * clearing the ones from the previous one.
2798        */
2799       free_current_action(csp->action);
2800       get_url_actions(csp, csp->http);
2801    }
2802
2803    enlist(csp->https_headers, csp->http->cmd);
2804
2805    /* Append the previously read headers */
2806    err = list_append_list_unique(csp->https_headers, headers);
2807    destroy_list(headers);
2808    if (JB_ERR_OK != err)
2809    {
2810       /* XXX: Send error message */
2811       return err;
2812    }
2813
2814    /* XXX: Work around crash */
2815    csp->error_message = NULL;
2816
2817    /* XXX: Why do this here? */
2818    csp->http->ssl = 1;
2819
2820    err = sed_https(csp);
2821    if (JB_ERR_OK != err)
2822    {
2823       ssl_send_data_delayed(&(csp->ssl_client_attr),
2824          (const unsigned char *)CHEADER, strlen(CHEADER), get_write_delay(csp));
2825       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
2826          csp->ip_addr_str);
2827       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
2828          csp->ip_addr_str, csp->http->cmd);
2829       return JB_ERR_PARSE;
2830    }
2831
2832    if ((NULL == csp->https_headers->first->str)
2833       || (strcmp(csp->http->cmd, csp->https_headers->first->str) &&
2834          (JB_ERR_OK != change_encrypted_request_destination(csp))))
2835    {
2836       ssl_send_data_delayed(&(csp->ssl_client_attr),
2837          (const unsigned char *)MESSED_UP_REQUEST_RESPONSE,
2838          strlen(MESSED_UP_REQUEST_RESPONSE), get_write_delay(csp));
2839       log_error(LOG_LEVEL_ERROR,
2840          "Invalid request line after applying header filters.");
2841       /* XXX: Use correct size */
2842       log_error(LOG_LEVEL_CLF,
2843          "%s - - [%T] \"Invalid request generated\" 400 0", csp->ip_addr_str);
2844
2845       return JB_ERR_PARSE;
2846    }
2847
2848    log_error(LOG_LEVEL_HEADER, "Encrypted request headers processed");
2849    log_error(LOG_LEVEL_REQUEST, "https://%s%s", csp->http->hostport,
2850       csp->http->path);
2851
2852    return err;
2853
2854 }
2855
2856 /*********************************************************************
2857  *
2858  * Function    :  cgi_page_requested
2859  *
2860  * Description :  Checks if a request is for an internal CGI page.
2861  *
2862  * Parameters  :
2863  *          1  :  host = The host requested by the client.
2864  *
2865  * Returns     :  1 if a CGI page has been requested, 0 otherwise
2866  *
2867  *********************************************************************/
2868 static int cgi_page_requested(const char *host)
2869 {
2870    if ((0 == strcmpic(host, CGI_SITE_1_HOST))
2871     || (0 == strcmpic(host, CGI_SITE_1_HOST "."))
2872     || (0 == strcmpic(host, CGI_SITE_2_HOST))
2873     || (0 == strcmpic(host, CGI_SITE_2_HOST ".")))
2874    {
2875       return 1;
2876    }
2877
2878    return 0;
2879
2880 }
2881
2882
2883 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2884 /*********************************************************************
2885  *
2886  * Function    :  continue_https_chat
2887  *
2888  * Description :  Behaves similar to chat() but only deals with
2889  *                https-inspected requests that arrive on an already
2890  *                established connection. The first request is always
2891  *                served by chat() which is a lot more complex as it
2892  *                has to deal with forwarding settings and connection
2893  *                failures etc.
2894  *
2895  *                If a connection to the server has already been
2896  *                opened it is reused unless the request is blocked
2897  *                or the forwarder changed.
2898  *
2899  *                If a connection to the server has not yet been
2900  *                opened (because the previous request was crunched),
2901  *                or the forwarder changed, the connection is dropped
2902  *                so that the client retries on a fresh one.
2903  *
2904  * Parameters  :
2905  *          1  :  csp = Current client state (buffers, headers, etc...)
2906  *
2907  * Returns     :  Nothing.
2908  *
2909  *********************************************************************/
2910 static void continue_https_chat(struct client_state *csp)
2911 {
2912    const struct forward_spec *fwd;
2913
2914    if (JB_ERR_OK != process_encrypted_request_headers(csp))
2915    {
2916       csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2917       return;
2918    }
2919
2920 #if defined(FEATURE_STATISTICS) && defined(MUTEX_LOCKS_AVAILABLE)
2921    privoxy_mutex_lock(&block_statistics_mutex);
2922    number_of_requests_received++;
2923    privoxy_mutex_unlock(&block_statistics_mutex);
2924 #endif
2925
2926    csp->requests_received_total++;
2927
2928    /*
2929     * We have an encrypted request. Check if one of the crunchers wants it.
2930     */
2931    if (crunch_response_triggered(csp, crunchers_all))
2932    {
2933       /*
2934        * Yes. The client got the crunch response and we're done here.
2935        */
2936       return;
2937    }
2938    if (csp->ssl_with_server_is_opened == 0)
2939    {
2940       log_error(LOG_LEVEL_CONNECT,
2941          "Dropping the client connection on socket %d. "
2942          "The server connection has not been established yet.",
2943          csp->cfd);
2944       csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2945       return;
2946    }
2947    assert(csp->server_connection.sfd != JB_INVALID_SOCKET);
2948
2949    if (csp->expected_client_content_length != 0 &&
2950       (client_body_filters_enabled(csp->action) ||
2951        client_body_taggers_enabled(csp->action)) &&
2952       can_buffer_request_body(csp))
2953    {
2954       int content_modified;
2955
2956       if (read_https_request_body(csp))
2957       {
2958          /* XXX: handle */
2959          return;
2960       }
2961       if (client_body_taggers_enabled(csp->action))
2962       {
2963          execute_client_body_taggers(csp, csp->expected_client_content_length);
2964          if (crunch_response_triggered(csp, crunchers_all))
2965          {
2966             /*
2967              * Yes. The client got the crunch response and we're done here.
2968              */
2969             return;
2970          }
2971       }
2972       if (client_body_filters_enabled(csp->action))
2973       {
2974          size_t modified_content_length = csp->expected_client_content_length;
2975          content_modified = execute_client_body_filters(csp,
2976             &modified_content_length);
2977          if ((content_modified == 1) &&
2978             (modified_content_length != csp->expected_client_content_length) &&
2979             update_client_headers(csp, modified_content_length))
2980          {
2981             /* XXX: Send error response */
2982             log_error(LOG_LEVEL_HEADER, "Error updating client headers");
2983             return;
2984          }
2985       }
2986       csp->expected_client_content_length = 0;
2987    }
2988
2989    fwd = forward_url(csp, csp->http);
2990    if (!connection_destination_matches(&csp->server_connection, csp->http, fwd))
2991    {
2992       log_error(LOG_LEVEL_CONNECT,
2993          "Dropping the client connection on socket %d with "
2994          "server socket %d connected to %s. The forwarder has changed.",
2995          csp->cfd, csp->server_connection.sfd, csp->server_connection.host);
2996       csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
2997       return;
2998    }
2999
3000    log_applied_actions(csp->action);
3001
3002    log_error(LOG_LEVEL_CONNECT,
3003       "Reusing server socket %d connected to %s. Requests already sent: %u.",
3004       csp->server_connection.sfd, csp->server_connection.host,
3005       csp->server_connection.requests_sent_total);
3006
3007    if (send_https_request(csp))
3008    {
3009       /*
3010        * Most likely the server connection timed out. We can't easily
3011        * create a new one so simply drop the client connection without a
3012        * error response to let the client retry.
3013        */
3014       log_error(LOG_LEVEL_CONNECT,
3015          "Dropping client connection on socket %d. "
3016          "Forwarding the encrypted client request failed.",
3017          csp->cfd);
3018       return;
3019    }
3020    csp->server_connection.request_sent = time(NULL);
3021    csp->server_connection.requests_sent_total++;
3022    handle_established_connection(csp);
3023    freez(csp->receive_buffer);
3024 }
3025 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3026 #endif
3027
3028
3029 /*********************************************************************
3030  *
3031  * Function    :  send_server_headers
3032  *
3033  * Description :  Sends the server headers to the client.
3034  *
3035  * Parameters  :
3036  *          1  :  csp = Current client state (buffers, headers, etc...)
3037  *
3038  * Returns     :  0 on succes, -1 on error.
3039  *
3040  *********************************************************************/
3041 static int send_server_headers(struct client_state *csp)
3042 {
3043    char *server_headers;
3044    int ret;
3045
3046    server_headers = list_to_text(csp->headers);
3047    if (server_headers == NULL)
3048    {
3049       /*
3050        * Memory is too tight to even generate the header.
3051        * Send our static "Out-of-memory" page.
3052        */
3053       log_error(LOG_LEVEL_ERROR,
3054          "Out of memory while trying to send server headers.");
3055       send_crunch_response(csp, cgi_error_memory());
3056       mark_server_socket_tainted(csp);
3057 #ifdef FEATURE_HTTPS_INSPECTION
3058       close_client_and_server_ssl_connections(csp);
3059 #endif
3060       return -1;
3061    }
3062 #ifdef FEATURE_HTTPS_INSPECTION
3063    if (client_use_ssl(csp))
3064    {
3065       ret = ssl_send_data_delayed(&(csp->ssl_client_attr),
3066          (const unsigned char *)server_headers, strlen(server_headers),
3067          get_write_delay(csp));
3068    }
3069    else
3070 #endif
3071    {
3072       ret = write_socket_delayed(csp->cfd, server_headers, strlen(server_headers),
3073          get_write_delay(csp));
3074    }
3075    freez(server_headers);
3076    if (ret < 0)
3077    {
3078       log_error(LOG_LEVEL_ERROR, "Failed to send server headers to the client.");
3079       mark_server_socket_tainted(csp);
3080 #ifdef FEATURE_HTTPS_INSPECTION
3081       close_client_and_server_ssl_connections(csp);
3082 #endif
3083       return -1;
3084    }
3085
3086    return 0;
3087
3088 }
3089
3090 /*********************************************************************
3091  *
3092  * Function    :  handle_established_connection
3093  *
3094  * Description :  Shuffle data between client and server once the
3095  *                connection has been established and the request
3096  *                has been sent.
3097  *
3098  * Parameters  :
3099  *          1  :  csp = Current client state (buffers, headers, etc...)
3100  *
3101  * Returns     :  Nothing.
3102  *
3103  *********************************************************************/
3104 static void handle_established_connection(struct client_state *csp)
3105 {
3106    char *p;
3107    int n;
3108 #ifdef HAVE_POLL
3109    struct pollfd poll_fds[2];
3110 #else
3111    fd_set rfds;
3112    jb_socket maxfd;
3113    struct timeval timeout;
3114 #endif
3115    int server_body;
3116    int ms_iis5_hack = 0;
3117    unsigned long long byte_count = 0;
3118    struct http_request *http;
3119    long len = 0; /* for buffer sizes (and negative error codes) */
3120    int buffer_and_filter_content = 0;
3121    unsigned int write_delay;
3122    size_t chunk_offset = 0;
3123 #ifdef FEATURE_HTTPS_INSPECTION
3124    int ret = 0;
3125    int use_ssl_tunnel = 0;
3126    csp->dont_verify_certificate = 0;
3127
3128    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION))
3129    {
3130       /* Pass encrypted content without filtering. */
3131       use_ssl_tunnel = 1;
3132    }
3133 #endif
3134
3135    /* Skeleton for HTTP response, if we should intercept the request */
3136    struct http_response *rsp;
3137 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3138    int watch_client_socket;
3139 #endif
3140
3141    csp->receive_buffer_size = csp->config->receive_buffer_size;
3142    csp->receive_buffer = zalloc(csp->receive_buffer_size + 1);
3143    if (csp->receive_buffer == NULL)
3144    {
3145       log_error(LOG_LEVEL_ERROR,
3146          "Out of memory. Failed to allocate the receive buffer.");
3147       rsp = cgi_error_memory();
3148       send_crunch_response(csp, rsp);
3149       return;
3150    }
3151
3152    http = csp->http;
3153
3154 #ifndef HAVE_POLL
3155    maxfd = (csp->cfd > csp->server_connection.sfd) ?
3156       csp->cfd : csp->server_connection.sfd;
3157 #endif
3158
3159    /* pass data between the client and server
3160     * until one or the other shuts down the connection.
3161     */
3162
3163    server_body = 0;
3164
3165 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3166    watch_client_socket = 0 == (csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING);
3167 #endif
3168    write_delay = get_write_delay(csp);
3169
3170    for (;;)
3171    {
3172 #ifdef FEATURE_HTTPS_INSPECTION
3173       if (server_use_ssl(csp) && is_ssl_pending(&(csp->ssl_server_attr)))
3174       {
3175          /*
3176           * It's possible that the TLS library already consumed all the
3177           * data the server intends to send. If that happens poll() and
3178           * select() will no longer see the data as available so we have
3179           * to skip the calls.
3180           */
3181          goto server_wants_to_talk;
3182       }
3183       if (watch_client_socket && client_use_ssl(csp) &&
3184          is_ssl_pending(&(csp->ssl_client_attr)))
3185       {
3186          /*
3187           * The TLS libray may also consume all of the remaining data
3188           * from the client when we're shuffling the data from an
3189           * unbuffered request body to the server.
3190           */
3191          goto client_wants_to_talk;
3192       }
3193 #endif
3194 #ifndef HAVE_POLL
3195       FD_ZERO(&rfds);
3196 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3197       if (!watch_client_socket)
3198       {
3199          maxfd = csp->server_connection.sfd;
3200       }
3201       else
3202 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3203       {
3204          FD_SET(csp->cfd, &rfds);
3205       }
3206
3207       FD_SET(csp->server_connection.sfd, &rfds);
3208 #endif /* ndef HAVE_POLL */
3209
3210 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3211       if (server_body && server_response_is_complete(csp, byte_count))
3212       {
3213          if (csp->expected_content_length == byte_count)
3214          {
3215             log_error(LOG_LEVEL_CONNECT,
3216                "Done reading from server. Content length: %llu as expected. "
3217                "Bytes most recently read: %ld.",
3218                byte_count, len);
3219          }
3220          else
3221          {
3222             log_error(LOG_LEVEL_CONNECT,
3223                "Done reading from server. Expected content length: %llu. "
3224                "Actual content length: %llu. Bytes most recently read: %ld.",
3225                csp->expected_content_length, byte_count, len);
3226          }
3227          len = 0;
3228          /*
3229           * XXX: Should not jump around, handle_established_connection()
3230           * is complicated enough already.
3231           */
3232          goto reading_done;
3233       }
3234 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
3235
3236 #ifdef HAVE_POLL
3237       poll_fds[0].fd = csp->cfd;
3238 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3239       if (!watch_client_socket)
3240       {
3241          /*
3242           * Ignore incoming data, but still watch out
3243           * for disconnects etc. These flags are always
3244           * implied anyway but explicitly setting them
3245           * doesn't hurt.
3246           */
3247          poll_fds[0].events = POLLERR|POLLHUP;
3248       }
3249       else
3250 #endif
3251       {
3252          poll_fds[0].events = POLLIN;
3253       }
3254       poll_fds[1].fd = csp->server_connection.sfd;
3255       poll_fds[1].events = POLLIN;
3256       n = poll(poll_fds, 2, csp->config->socket_timeout * 1000);
3257 #else
3258       timeout.tv_sec = csp->config->socket_timeout;
3259       timeout.tv_usec = 0;
3260       n = select((int)maxfd + 1, &rfds, NULL, NULL, &timeout);
3261 #endif /* def HAVE_POLL */
3262
3263       /* Server or client not responding in timeout */
3264       if (n == 0)
3265       {
3266          log_error(LOG_LEVEL_CONNECT, "Socket timeout %d reached: %s",
3267             csp->config->socket_timeout, http->url);
3268          if ((byte_count == 0) && (http->ssl == 0))
3269          {
3270             send_crunch_response(csp, error_response(csp, "connection-timeout"));
3271          }
3272          mark_server_socket_tainted(csp);
3273 #ifdef FEATURE_HTTPS_INSPECTION
3274          close_client_and_server_ssl_connections(csp);
3275 #endif
3276          return;
3277       }
3278       else if (n < 0)
3279       {
3280 #ifdef HAVE_POLL
3281          log_error(LOG_LEVEL_ERROR, "poll() failed!: %E");
3282 #else
3283          log_error(LOG_LEVEL_ERROR, "select() failed!: %E");
3284 #endif
3285          mark_server_socket_tainted(csp);
3286 #ifdef FEATURE_HTTPS_INSPECTION
3287          close_client_and_server_ssl_connections(csp);
3288 #endif
3289          return;
3290       }
3291
3292       /*
3293        * This is the body of the browser's request,
3294        * just read and write it.
3295        *
3296        * Receives data from browser and sends it to server
3297        *
3298        * XXX: Make sure the client doesn't use pipelining
3299        * behind Privoxy's back.
3300        */
3301 #ifdef HAVE_POLL
3302       if ((poll_fds[0].revents & (POLLERR|POLLHUP|POLLNVAL)) != 0)
3303       {
3304          log_error(LOG_LEVEL_CONNECT,
3305             "The client socket %d has become unusable while "
3306             "the server socket %d is still open.",
3307             csp->cfd, csp->server_connection.sfd);
3308          mark_server_socket_tainted(csp);
3309          break;
3310       }
3311
3312       if (poll_fds[0].revents != 0)
3313 #else
3314       if (FD_ISSET(csp->cfd, &rfds))
3315 #endif /* def HAVE_POLL*/
3316       {
3317          int max_bytes_to_read;
3318
3319 #ifdef FEATURE_HTTPS_INSPECTION
3320          client_wants_to_talk:
3321 #endif
3322
3323          max_bytes_to_read = (int)csp->receive_buffer_size;
3324
3325 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3326          if ((csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ))
3327          {
3328             if (data_is_available(csp->cfd, 0))
3329             {
3330                /*
3331                 * If the next request is already waiting, we have
3332                 * to stop select()ing the client socket. Otherwise
3333                 * we would always return right away and get nothing
3334                 * else done.
3335                 */
3336                watch_client_socket = 0;
3337                log_error(LOG_LEVEL_CONNECT,
3338                   "Stop watching client socket %d. "
3339                   "There's already another request waiting.",
3340                   csp->cfd);
3341                continue;
3342             }
3343             /*
3344              * If the client socket is set, but there's no data
3345              * available on the socket, the client went fishing
3346              * and continuing talking to the server makes no sense.
3347              */
3348             log_error(LOG_LEVEL_CONNECT,
3349                "The client closed socket %d while "
3350                "the server socket %d is still open.",
3351                csp->cfd, csp->server_connection.sfd);
3352             mark_server_socket_tainted(csp);
3353             break;
3354          }
3355          if (csp->expected_client_content_length != 0)
3356          {
3357             if (csp->expected_client_content_length < csp->receive_buffer_size)
3358             {
3359                max_bytes_to_read = (int)csp->expected_client_content_length;
3360             }
3361             log_error(LOG_LEVEL_CONNECT,
3362                "Waiting for up to %d bytes from the client.",
3363                max_bytes_to_read);
3364          }
3365          assert(max_bytes_to_read <= csp->receive_buffer_size);
3366 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3367
3368 #ifdef FEATURE_HTTPS_INSPECTION
3369          if (client_use_ssl(csp))
3370          {
3371             if (csp->http->status == 101)
3372             {
3373                len = ssl_recv_data(&(csp->ssl_client_attr),
3374                   (unsigned char *)csp->receive_buffer,
3375                   (size_t)max_bytes_to_read);
3376                if (len == -1)
3377                {
3378                   log_error(LOG_LEVEL_ERROR, "Failed to receive data "
3379                      "on client socket %d for an upgraded connection",
3380                      csp->cfd);
3381                   break;
3382                }
3383                if (len == 0)
3384                {
3385                   log_error(LOG_LEVEL_CONNECT, "Done receiving data "
3386                      "on client socket %d for an upgraded connection",
3387                      csp->cfd);
3388                   break;
3389                }
3390                byte_count += (unsigned long long)len;
3391                len = ssl_send_data(&(csp->ssl_server_attr),
3392                   (unsigned char *)csp->receive_buffer, (size_t)len);
3393                if (len == -1)
3394                {
3395                   log_error(LOG_LEVEL_ERROR, "Failed to send data "
3396                      "on server socket %d for an upgraded connection",
3397                      csp->server_connection.sfd);
3398                   break;
3399                }
3400                continue;
3401             }
3402             log_error(LOG_LEVEL_CONNECT, "Breaking with TLS/SSL.");
3403             break;
3404          }
3405          else
3406 #endif /* def FEATURE_HTTPS_INSPECTION */
3407          {
3408             len = read_socket(csp->cfd, csp->receive_buffer, max_bytes_to_read);
3409
3410             if (len <= 0)
3411             {
3412                /* XXX: not sure if this is necessary. */
3413                mark_server_socket_tainted(csp);
3414                break; /* "game over, man" */
3415             }
3416
3417 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3418             if (csp->expected_client_content_length != 0)
3419             {
3420                assert(len <= max_bytes_to_read);
3421                csp->expected_client_content_length -= (unsigned)len;
3422                log_error(LOG_LEVEL_CONNECT,
3423                   "Expected client content length set to %llu "
3424                   "after reading %ld bytes.",
3425                   csp->expected_client_content_length, len);
3426                if (csp->expected_client_content_length == 0)
3427                {
3428                   log_error(LOG_LEVEL_CONNECT,
3429                      "Done reading from the client.");
3430                   csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
3431                }
3432             }
3433 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3434
3435             if (write_socket(csp->server_connection.sfd, csp->receive_buffer, (size_t)len))
3436             {
3437                log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host);
3438                mark_server_socket_tainted(csp);
3439                return;
3440             }
3441          }
3442          continue;
3443       }
3444
3445       /*
3446        * The server wants to talk. It could be the header or the body.
3447        */
3448 #ifdef HAVE_POLL
3449       if (poll_fds[1].revents != 0)
3450 #else
3451       if (FD_ISSET(csp->server_connection.sfd, &rfds))
3452 #endif /* HAVE_POLL */
3453       {
3454 #ifdef FEATURE_HTTPS_INSPECTION
3455          server_wants_to_talk:
3456 #endif
3457 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3458          /*
3459           * If we are buffering content, we don't want to eat up to
3460           * buffer-limit bytes if the client no longer cares about them.
3461           * If we aren't buffering, however, a dead client socket will be
3462           * noticed pretty much right away anyway, so we can reduce the
3463           * overhead by skipping the check.
3464           */
3465          if (buffer_and_filter_content && !socket_is_still_alive(csp->cfd))
3466          {
3467 #ifdef _WIN32
3468             log_error(LOG_LEVEL_CONNECT,
3469                "The server still wants to talk, but the client may already have hung up on us.");
3470 #else
3471             log_error(LOG_LEVEL_CONNECT,
3472                "The server still wants to talk, but the client hung up on us.");
3473             mark_server_socket_tainted(csp);
3474 #ifdef FEATURE_HTTPS_INSPECTION
3475             close_client_and_server_ssl_connections(csp);
3476 #endif
3477             return;
3478 #endif /* def _WIN32 */
3479          }
3480 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3481
3482 #ifdef FEATURE_HTTPS_INSPECTION
3483          /*
3484           * Reading data from standard or secured connection (HTTP/HTTPS)
3485           */
3486          if (server_use_ssl(csp))
3487          {
3488             len = ssl_recv_data(&(csp->ssl_server_attr),
3489                (unsigned char *)csp->receive_buffer, csp->receive_buffer_size);
3490          }
3491          else
3492 #endif
3493          {
3494             len = read_socket(csp->server_connection.sfd, csp->receive_buffer,
3495                (int)csp->receive_buffer_size);
3496          }
3497
3498          if (len < 0)
3499          {
3500             log_error(LOG_LEVEL_ERROR, "read from: %s failed: %E", http->host);
3501
3502             if ((http->ssl && (csp->fwd == NULL))
3503 #ifdef FEATURE_HTTPS_INSPECTION
3504                && use_ssl_tunnel
3505 #endif
3506                 )
3507             {
3508                /*
3509                 * Just hang up. We already confirmed the client's CONNECT
3510                 * request with status code 200 and unencrypted content is
3511                 * no longer welcome.
3512                 */
3513                log_error(LOG_LEVEL_ERROR,
3514                   "CONNECT already confirmed. Unable to tell the client about the problem.");
3515                return;
3516             }
3517             else if (byte_count)
3518             {
3519                /*
3520                 * Just hang up. We already transmitted the original headers
3521                 * and parts of the original content and therefore missed the
3522                 * chance to send an error message (without risking data corruption).
3523                 *
3524                 * XXX: we could retry with a fancy range request here.
3525                 */
3526                log_error(LOG_LEVEL_ERROR, "Already forwarded the original headers. "
3527                   "Unable to tell the client about the problem.");
3528                mark_server_socket_tainted(csp);
3529 #ifdef FEATURE_HTTPS_INSPECTION
3530                close_client_and_server_ssl_connections(csp);
3531 #endif
3532                return;
3533             }
3534             /*
3535              * XXX: Consider handling the cases above the same.
3536              */
3537             mark_server_socket_tainted(csp);
3538             len = 0;
3539          }
3540
3541 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3542          reading_done:
3543 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
3544
3545          /*
3546           * This is guaranteed by allocating with zalloc_or_die()
3547           * and never (intentionally) writing to the last byte.
3548           *
3549           * csp->receive_buffer_size is the size of the part of the
3550           * buffer we intentionally write to, but we actually
3551           * allocated csp->receive_buffer_size+1 bytes so the assertion
3552           * stays within the allocated range.
3553           */
3554          assert(csp->receive_buffer[csp->receive_buffer_size] == '\0');
3555
3556          /*
3557           * Add a trailing zero to let be able to use string operations.
3558           * XXX: do we still need this with filter_popups gone?
3559           */
3560          assert(len <= csp->receive_buffer_size);
3561          csp->receive_buffer[len] = '\0';
3562
3563          /*
3564           * Normally, this would indicate that we've read
3565           * as much as the server has sent us and we can
3566           * close the client connection.  However, Microsoft
3567           * in its wisdom has released IIS/5 with a bug that
3568           * prevents it from sending the trailing \r\n in
3569           * a 302 redirect header (and possibly other headers).
3570           * To work around this if we've haven't parsed
3571           * a full header we'll append a trailing \r\n
3572           * and see if this now generates a valid one.
3573           *
3574           * This hack shouldn't have any impacts.  If we've
3575           * already transmitted the header or if this is a
3576           * SSL connection, then we won't bother with this
3577           * hack.  So we only work on partially received
3578           * headers.  If we append a \r\n and this still
3579           * doesn't generate a valid header, then we won't
3580           * transmit anything to the client.
3581           */
3582          if (len == 0)
3583          {
3584
3585             if (server_body || (http->ssl
3586 #ifdef FEATURE_HTTPS_INSPECTION
3587                   && use_ssl_tunnel
3588 #endif
3589                ))
3590             {
3591                /*
3592                 * If we have been buffering up the document,
3593                 * now is the time to apply content modification
3594                 * and send the result to the client.
3595                 */
3596                if (buffer_and_filter_content)
3597                {
3598                   p = execute_content_filters(csp);
3599                   /*
3600                    * If content filtering fails, use the original
3601                    * buffer and length.
3602                    * (see p != NULL ? p : csp->iob->cur below)
3603                    */
3604                   if (NULL == p)
3605                   {
3606                      csp->content_length = (size_t)(csp->iob->eod - csp->iob->cur);
3607                   }
3608 #ifdef FEATURE_COMPRESSION
3609                   else if ((csp->flags & CSP_FLAG_CLIENT_SUPPORTS_DEFLATE)
3610                      && (csp->content_length > LOWER_LENGTH_LIMIT_FOR_COMPRESSION))
3611                   {
3612                      char *compressed_content = compress_buffer(p,
3613                         (size_t *)&csp->content_length, csp->config->compression_level);
3614                      if (compressed_content != NULL)
3615                      {
3616                         freez(p);
3617                         p = compressed_content;
3618                         csp->flags |= CSP_FLAG_BUFFERED_CONTENT_DEFLATED;
3619                      }
3620                   }
3621 #endif
3622
3623                   if (JB_ERR_OK != update_server_headers(csp))
3624                   {
3625                      log_error(LOG_LEVEL_FATAL,
3626                         "Failed to update server headers. after filtering.");
3627                   }
3628
3629                   if (send_server_headers(csp))
3630                   {
3631                      return;
3632                   }
3633
3634 #ifdef FEATURE_HTTPS_INSPECTION
3635                   /*
3636                    * Sending data with standard or secured connection (HTTP/HTTPS)
3637                    */
3638                   if (client_use_ssl(csp))
3639                   {
3640                      if (ssl_send_data_delayed(&(csp->ssl_client_attr),
3641                               (const unsigned char *) ((p != NULL) ? p : csp->iob->cur),
3642                               csp->content_length, get_write_delay(csp)) < 0)
3643                      {
3644                         log_error(LOG_LEVEL_ERROR,
3645                            "Failed to send the modified content to the client over TLS");
3646                         freez(p);
3647                         mark_server_socket_tainted(csp);
3648                         close_client_and_server_ssl_connections(csp);
3649                         return;
3650                      }
3651                   }
3652                   else
3653 #endif /* def FEATURE_HTTPS_INSPECTION */
3654                   {
3655                      if (write_socket_delayed(csp->cfd, ((p != NULL) ? p : csp->iob->cur),
3656                          (size_t)csp->content_length, write_delay))
3657                      {
3658                         log_error(LOG_LEVEL_ERROR, "write modified content to client failed: %E");
3659                         freez(p);
3660                         mark_server_socket_tainted(csp);
3661                         return;
3662                      }
3663                   }
3664
3665                   freez(p);
3666                }
3667
3668                break; /* "game over, man" */
3669             }
3670
3671             /*
3672              * This is not the body, so let's pretend the server just sent
3673              * us a blank line.
3674              */
3675             snprintf(csp->receive_buffer, csp->receive_buffer_size, "\r\n");
3676             len = (int)strlen(csp->receive_buffer);
3677
3678             /*
3679              * Now, let the normal header parsing algorithm below do its
3680              * job.  If it fails, we'll exit instead of continuing.
3681              */
3682
3683             ms_iis5_hack = 1;
3684          }
3685
3686          /*
3687           * If we're in the body of the server document, just write it to
3688           * the client, unless we need to buffer the body for later
3689           * content-filtering.
3690           */
3691          if (server_body || (http->ssl
3692 #ifdef FEATURE_HTTPS_INSPECTION
3693                && use_ssl_tunnel
3694 #endif
3695             ))
3696          {
3697             if (buffer_and_filter_content)
3698             {
3699                /*
3700                 * If there is no memory left for buffering the content, or the buffer limit
3701                 * has been reached, switch to non-filtering mode, i.e. make & write the
3702                 * header, flush the iob and buf, and get out of the way.
3703                 */
3704                if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3705                {
3706                   long flushed;
3707
3708                   log_error(LOG_LEVEL_INFO,
3709                      "Flushing header and buffers. Stepping back from filtering.");
3710
3711                   if (send_server_headers(csp))
3712                   {
3713                      return;
3714                   }
3715
3716 #ifdef FEATURE_HTTPS_INSPECTION
3717                   /*
3718                    * Sending data with standard or secured connection (HTTP/HTTPS)
3719                    */
3720                   if (client_use_ssl(csp))
3721                   {
3722                      if (((flushed = ssl_flush_socket(&(csp->ssl_client_attr),
3723                                 csp->iob)) < 0)
3724                         || (ssl_send_data_delayed(&(csp->ssl_client_attr),
3725                               (const unsigned char *)csp->receive_buffer, (size_t)len,
3726                               get_write_delay(csp)) < 0))
3727                      {
3728                         log_error(LOG_LEVEL_CONNECT,
3729                            "Flush header and buffers to client failed");
3730                         mark_server_socket_tainted(csp);
3731                         close_client_and_server_ssl_connections(csp);
3732                         return;
3733                      }
3734                   }
3735                   else
3736 #endif /* def FEATURE_HTTPS_INSPECTION */
3737                   {
3738                      if (((flushed = flush_iob(csp->cfd, csp->iob, write_delay)) < 0)
3739                       || write_socket_delayed(csp->cfd, csp->receive_buffer, (size_t)len,
3740                             write_delay))
3741                      {
3742                         log_error(LOG_LEVEL_CONNECT,
3743                            "Flush header and buffers to client failed: %E");
3744                         mark_server_socket_tainted(csp);
3745                         return;
3746                      }
3747                   }
3748
3749                   /*
3750                    * Reset the byte_count to the amount of bytes we just
3751                    * flushed. len will be added a few lines below.
3752                    */
3753                   byte_count = (unsigned long long)flushed;
3754                   if ((csp->flags & CSP_FLAG_CHUNKED) && (chunk_offset != 0))
3755                   {
3756                      log_error(LOG_LEVEL_CONNECT,
3757                         "Reducing chunk offset %lu by %ld to %lu.", chunk_offset, flushed,
3758                         (chunk_offset - (unsigned)flushed));
3759                      assert(chunk_offset >= flushed); /* XXX: Reachable with malicious input? */
3760                      chunk_offset -= (unsigned)flushed;
3761
3762                      /* Make room in the iob. */
3763                      csp->iob->cur = csp->iob->eod = csp->iob->buf;
3764
3765                      if (add_to_iob(csp->iob, csp->config->buffer_limit,
3766                            csp->receive_buffer, len))
3767                      {
3768                         /* This is not supposed to happen but ... */
3769                         csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
3770                         log_error(LOG_LEVEL_ERROR, "Failed to buffer %ld bytes of "
3771                            "chunk-encoded data after resetting the buffer.", len);
3772                         return;
3773                      }
3774                   }
3775                   buffer_and_filter_content = 0;
3776                   server_body = 1;
3777                }
3778             }
3779             else
3780             {
3781 #ifdef FEATURE_HTTPS_INSPECTION
3782                /*
3783                 * Sending data with standard or secured connection (HTTP/HTTPS)
3784                 */
3785                if (client_use_ssl(csp))
3786                {
3787                   ret = ssl_send_data_delayed(&(csp->ssl_client_attr),
3788                      (const unsigned char *)csp->receive_buffer, (size_t)len,
3789                      get_write_delay(csp));
3790                   if (ret < 0)
3791                   {
3792                      log_error(LOG_LEVEL_ERROR,
3793                         "Sending data to client failed");
3794                      mark_server_socket_tainted(csp);
3795                      close_client_and_server_ssl_connections(csp);
3796                      return;
3797                   }
3798                }
3799                else
3800 #endif /* def FEATURE_HTTPS_INSPECTION */
3801                {
3802                   if (write_socket_delayed(csp->cfd, csp->receive_buffer,
3803                         (size_t)len, write_delay))
3804                   {
3805                      log_error(LOG_LEVEL_ERROR, "write to client failed: %E");
3806                      mark_server_socket_tainted(csp);
3807                      return;
3808                   }
3809                }
3810                if (csp->flags & CSP_FLAG_CHUNKED)
3811                {
3812                   /*
3813                    * While we don't need the data to filter it, put it in the
3814                    * buffer so we can keep track of the offset to the start of
3815                    * the next chunk and detect when the response is finished.
3816                    */
3817                   size_t encoded_bytes = (size_t)(csp->iob->eod - csp->iob->cur);
3818
3819                   if (csp->config->buffer_limit / 4 < encoded_bytes)
3820                   {
3821                      /*
3822                       * Reset the buffer to reduce the memory footprint.
3823                       */
3824                      log_error(LOG_LEVEL_CONNECT,
3825                         "Reducing the chunk offset from %lu to %lu after "
3826                         "discarding %lu bytes to make room in the buffer.",
3827                         chunk_offset, (chunk_offset - encoded_bytes),
3828                         encoded_bytes);
3829                      chunk_offset -= encoded_bytes;
3830                      csp->iob->cur = csp->iob->eod = csp->iob->buf;
3831                   }
3832                   if (add_to_iob(csp->iob, csp->config->buffer_limit,
3833                      csp->receive_buffer, len))
3834                   {
3835                      /* This is not supposed to happen but ... */
3836                      csp->flags &= ~CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
3837                      log_error(LOG_LEVEL_ERROR,
3838                         "Failed to buffer %ld bytes of chunk-encoded data.",
3839                         len);
3840                      return;
3841                   }
3842                }
3843             }
3844             byte_count += (unsigned long long)len;
3845
3846             if (csp->flags & CSP_FLAG_CHUNKED)
3847             {
3848                int rc;
3849                size_t encoded_bytes = (size_t)(csp->iob->eod - csp->iob->cur);
3850
3851                rc = get_bytes_missing_from_chunked_data(csp->iob->cur, encoded_bytes,
3852                   chunk_offset);
3853                if (rc >= 0)
3854                {
3855                   if (rc != 0)
3856                   {
3857                      chunk_offset = (size_t)rc;
3858                   }
3859
3860                   if (chunked_data_is_complete(csp->iob->cur, encoded_bytes, chunk_offset))
3861                   {
3862                      log_error(LOG_LEVEL_CONNECT,
3863                         "We buffered the last chunk of the response.");
3864                      csp->expected_content_length = byte_count;
3865                      csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
3866                   }
3867                }
3868             }
3869
3870             continue;
3871          }
3872          else
3873          {
3874             /*
3875              * We're still looking for the end of the server's header.
3876              * Buffer up the data we just read.  If that fails, there's
3877              * little we can do but send our static out-of-memory page.
3878              */
3879             if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3880             {
3881                log_error(LOG_LEVEL_ERROR, "Out of memory while looking for end of server headers.");
3882                rsp = cgi_error_memory();
3883                send_crunch_response(csp, rsp);
3884                mark_server_socket_tainted(csp);
3885 #ifdef FEATURE_HTTPS_INSPECTION
3886                close_client_and_server_ssl_connections(csp);
3887 #endif
3888                return;
3889             }
3890
3891             /* Convert iob into something sed() can digest */
3892             if (JB_ERR_PARSE == get_server_headers(csp))
3893             {
3894                if (ms_iis5_hack)
3895                {
3896                   /*
3897                    * Well, we tried our MS IIS/5 hack and it didn't work.
3898                    * The header is incomplete and there isn't anything
3899                    * we can do about it.
3900                    */
3901                   log_error(LOG_LEVEL_ERROR, "Invalid server headers. "
3902                      "Applying the MS IIS5 hack didn't help.");
3903                   log_error(LOG_LEVEL_CLF,
3904                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3905 #ifdef FEATURE_HTTPS_INSPECTION
3906                   /*
3907                    * Sending data with standard or secured connection (HTTP/HTTPS)
3908                    */
3909                   if (client_use_ssl(csp))
3910                   {
3911                      ssl_send_data_delayed(&(csp->ssl_client_attr),
3912                         (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3913                         strlen(INVALID_SERVER_HEADERS_RESPONSE), get_write_delay(csp));
3914                   }
3915                   else
3916 #endif /* def FEATURE_HTTPS_INSPECTION */
3917                   {
3918                      write_socket_delayed(csp->cfd,
3919                         INVALID_SERVER_HEADERS_RESPONSE,
3920                         strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3921                   }
3922                   mark_server_socket_tainted(csp);
3923 #ifdef FEATURE_HTTPS_INSPECTION
3924                   close_client_and_server_ssl_connections(csp);
3925 #endif
3926                   return;
3927                }
3928                else
3929                {
3930                   /*
3931                    * Since we have to wait for more from the server before
3932                    * we can parse the headers we just continue here.
3933                    */
3934                   log_error(LOG_LEVEL_CONNECT,
3935                      "Continuing buffering server headers from socket %d. "
3936                      "Bytes most recently read: %ld.", csp->cfd, len);
3937                   continue;
3938                }
3939             }
3940             else
3941             {
3942                /*
3943                 * Account for the content bytes we
3944                 * might have gotten with the headers.
3945                 */
3946                assert(csp->iob->eod >= csp->iob->cur);
3947                byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
3948             }
3949
3950             /* Did we actually get anything? */
3951             if (NULL == csp->headers->first)
3952             {
3953                if ((csp->flags & CSP_FLAG_REUSED_CLIENT_CONNECTION))
3954                {
3955                   log_error(LOG_LEVEL_ERROR,
3956                      "No server or forwarder response received on socket %d. "
3957                      "Closing client socket %d without sending data.",
3958                      csp->server_connection.sfd, csp->cfd);
3959                   log_error(LOG_LEVEL_CLF,
3960                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3961                }
3962                else
3963                {
3964                   log_error(LOG_LEVEL_ERROR,
3965                      "No server or forwarder response received on socket %d.",
3966                      csp->server_connection.sfd);
3967                   send_crunch_response(csp, error_response(csp, "no-server-data"));
3968                }
3969                free_http_request(http);
3970                mark_server_socket_tainted(csp);
3971 #ifdef FEATURE_HTTPS_INSPECTION
3972                close_client_and_server_ssl_connections(csp);
3973 #endif
3974                return;
3975             }
3976
3977             if (!csp->headers->first->str)
3978             {
3979                log_error(LOG_LEVEL_ERROR, "header search: csp->headers->first->str == NULL, assert will be called");
3980             }
3981             assert(csp->headers->first->str);
3982
3983             if (strncmpic(csp->headers->first->str, "HTTP", 4) &&
3984                 strncmpic(csp->headers->first->str, "ICY", 3))
3985             {
3986                /*
3987                 * It doesn't look like a HTTP (or Shoutcast) response:
3988                 * tell the client and log the problem.
3989                 */
3990                if (strlen(csp->headers->first->str) > 30)
3991                {
3992                   csp->headers->first->str[30] = '\0';
3993                }
3994                log_error(LOG_LEVEL_ERROR,
3995                   "Invalid server or forwarder response. Starts with: %s",
3996                   csp->headers->first->str);
3997                log_error(LOG_LEVEL_CLF,
3998                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3999 #ifdef FEATURE_HTTPS_INSPECTION
4000                /*
4001                 * Sending data with standard or secured connection (HTTP/HTTPS)
4002                 */
4003                if (client_use_ssl(csp))
4004                {
4005                   ssl_send_data_delayed(&(csp->ssl_client_attr),
4006                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
4007                      strlen(INVALID_SERVER_HEADERS_RESPONSE),
4008                      get_write_delay(csp));
4009                }
4010                else
4011 #endif /* def FEATURE_HTTPS_INSPECTION */
4012                {
4013                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
4014                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
4015                }
4016                free_http_request(http);
4017                mark_server_socket_tainted(csp);
4018 #ifdef FEATURE_HTTPS_INSPECTION
4019                close_client_and_server_ssl_connections(csp);
4020 #endif
4021                return;
4022             }
4023
4024             /*
4025              * Disable redirect checkers, so that they will be only run
4026              * again if the user also enables them through tags.
4027              *
4028              * From a performance point of view it doesn't matter,
4029              * but it prevents duplicated log messages.
4030              */
4031 #ifdef FEATURE_FAST_REDIRECTS
4032             csp->action->flags &= ~ACTION_FAST_REDIRECTS;
4033 #endif
4034             csp->action->flags &= ~ACTION_REDIRECT;
4035
4036             /*
4037              * We have now received the entire server header,
4038              * filter it and send the result to the client
4039              */
4040             if (JB_ERR_OK != sed(csp, FILTER_SERVER_HEADERS))
4041             {
4042                log_error(LOG_LEVEL_CLF,
4043                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
4044 #ifdef FEATURE_HTTPS_INSPECTION
4045                /*
4046                 * Sending data with standard or secured connection (HTTP/HTTPS)
4047                 */
4048                if (client_use_ssl(csp))
4049                {
4050                   ssl_send_data_delayed(&(csp->ssl_client_attr),
4051                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
4052                      strlen(INVALID_SERVER_HEADERS_RESPONSE),
4053                      get_write_delay(csp));
4054                }
4055                else
4056 #endif
4057                {
4058                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
4059                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
4060                }
4061                free_http_request(http);
4062                mark_server_socket_tainted(csp);
4063 #ifdef FEATURE_HTTPS_INSPECTION
4064                close_client_and_server_ssl_connections(csp);
4065 #endif
4066                return;
4067             }
4068
4069             if ((csp->flags & CSP_FLAG_CHUNKED)
4070                && !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET))
4071             {
4072                int rc;
4073                size_t encoded_size = (size_t)(csp->iob->eod - csp->iob->cur);
4074
4075                rc = get_bytes_missing_from_chunked_data(csp->iob->cur, encoded_size,
4076                   chunk_offset);
4077                if (rc >= 0)
4078                {
4079                   if (rc != 0)
4080                   {
4081                      chunk_offset = (size_t)rc;
4082                   }
4083                   if (chunked_data_is_complete(csp->iob->cur, encoded_size, chunk_offset))
4084                   {
4085                      log_error(LOG_LEVEL_CONNECT,
4086                         "Looks like we got the last chunk together with "
4087                         "the server headers. We better stop reading.");
4088                      byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
4089                      csp->expected_content_length = byte_count;
4090                      csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
4091                   }
4092                }
4093             }
4094             csp->server_connection.response_received = time(NULL);
4095
4096             if (crunch_response_triggered(csp, crunchers_light))
4097             {
4098                /*
4099                 * One of the tags created by a server-header
4100                 * tagger triggered a crunch. We already
4101                 * delivered the crunch response to the client
4102                 * and are done here after cleaning up.
4103                 */
4104                mark_server_socket_tainted(csp);
4105 #ifdef FEATURE_HTTPS_INSPECTION
4106                close_client_and_server_ssl_connections(csp);
4107 #endif
4108                return;
4109             }
4110
4111             /* Buffer and pcrs filter this if appropriate. */
4112             buffer_and_filter_content = content_requires_filtering(csp);
4113
4114             if (!buffer_and_filter_content)
4115             {
4116                /*
4117                 * Write the server's (modified) header to
4118                 * the client (along with anything else that
4119                 * may be in the buffer). Use standard or secured
4120                 * connection.
4121                 */
4122                if (send_server_headers(csp))
4123                {
4124                   return;
4125                }
4126 #ifdef FEATURE_HTTPS_INSPECTION
4127                if (client_use_ssl(csp))
4128                {
4129                   if ((len = ssl_flush_socket(&(csp->ssl_client_attr),
4130                            csp->iob)) < 0)
4131                   {
4132                      log_error(LOG_LEVEL_CONNECT,
4133                         "Sending buffered bytes to the client failed");
4134
4135                      /*
4136                       * The write failed, so don't bother mentioning it
4137                       * to the client... it probably can't hear us anyway.
4138                       */
4139                      mark_server_socket_tainted(csp);
4140 #ifdef FEATURE_HTTPS_INSPECTION
4141                      close_client_and_server_ssl_connections(csp);
4142 #endif
4143                      return;
4144                   }
4145                }
4146                else
4147 #endif /* def FEATURE_HTTPS_INSPECTION */
4148                {
4149                   if ((len = flush_iob(csp->cfd, csp->iob, write_delay)) < 0)
4150                   {
4151                      log_error(LOG_LEVEL_ERROR,
4152                         "Sending buffered bytes to the client failed.");
4153                      /*
4154                       * The write failed, so don't bother mentioning it
4155                       * to the client... it probably can't hear us anyway.
4156                       */
4157                      mark_server_socket_tainted(csp);
4158                      return;
4159                   }
4160                }
4161                if (csp->flags & CSP_FLAG_CHUNKED &&
4162                  !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET))
4163                {
4164                   /*
4165                    * In case of valid data we shouldn't flush more
4166                    * data than chunk_offset but the data may be invalid.
4167                    */
4168                   if (chunk_offset >= len)
4169                   {
4170                      log_error(LOG_LEVEL_CONNECT, "Reducing the chunk offset "
4171                         "from %lu to %lu after flushing %ld bytes.",
4172                         chunk_offset, (chunk_offset - (unsigned)len), len);
4173                      chunk_offset = chunk_offset - (unsigned)len;
4174                   }
4175                   else
4176                   {
4177                      log_error(LOG_LEVEL_CONNECT,
4178                         "Keeping chunk offset at %lu despite flushing %ld bytes",
4179                         chunk_offset, len);
4180                      /*
4181                       * If we can't parse the chunk-encoded data we should
4182                       * not reuse the server connection.
4183                       */
4184                      mark_server_socket_tainted(csp);
4185                   }
4186                }
4187                                 }
4188
4189             /* we're finished with the server's header */
4190
4191             server_body = 1;
4192
4193             /*
4194              * If this was a MS IIS/5 hack then it means the server
4195              * has already closed the connection. Nothing more to read.
4196              * Time to bail.
4197              */
4198             if (ms_iis5_hack)
4199             {
4200                log_error(LOG_LEVEL_ERROR,
4201                   "Closed server connection detected. "
4202                   "Applying the MS IIS5 hack didn't help.");
4203                log_error(LOG_LEVEL_CLF,
4204                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
4205 #ifdef FEATURE_HTTPS_INSPECTION
4206                /*
4207                 * Sending data with standard or secured connection (HTTP/HTTPS)
4208                 */
4209                if (client_use_ssl(csp))
4210                {
4211                   ssl_send_data_delayed(&(csp->ssl_client_attr),
4212                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
4213                      strlen(INVALID_SERVER_HEADERS_RESPONSE),
4214                      get_write_delay(csp));
4215                }
4216                else
4217 #endif /* def FEATURE_HTTPS_INSPECTION */
4218                {
4219                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
4220                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
4221                }
4222                mark_server_socket_tainted(csp);
4223 #ifdef FEATURE_HTTPS_INSPECTION
4224                close_client_and_server_ssl_connections(csp);
4225 #endif
4226                return;
4227             }
4228          }
4229          continue;
4230       }
4231       mark_server_socket_tainted(csp);
4232 #ifdef FEATURE_HTTPS_INSPECTION
4233       close_client_and_server_ssl_connections(csp);
4234 #endif
4235       return; /* huh? we should never get here */
4236    }
4237
4238    if (csp->content_length == 0)
4239    {
4240       /*
4241        * If Privoxy didn't recalculate the Content-Length,
4242        * byte_count is still correct.
4243        */
4244       csp->content_length = byte_count;
4245    }
4246
4247 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4248    if ((csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
4249       && (csp->expected_content_length != byte_count))
4250    {
4251       log_error(LOG_LEVEL_CONNECT,
4252          "Received %llu bytes while expecting %llu.",
4253          byte_count, csp->expected_content_length);
4254       mark_server_socket_tainted(csp);
4255    }
4256 #endif
4257
4258 #ifdef FEATURE_HTTPS_INSPECTION
4259    if (client_use_ssl(csp))
4260    {
4261       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s https://%s%s %s\" 200 %llu",
4262          csp->ip_addr_str, http->gpc, http->hostport, http->path,
4263          http->version, csp->content_length);
4264    }
4265    else
4266 #endif
4267    {
4268       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 %llu",
4269          csp->ip_addr_str, http->ocmd, csp->content_length);
4270    }
4271    csp->server_connection.timestamp = time(NULL);
4272 }
4273
4274
4275 /*********************************************************************
4276  *
4277  * Function    :  chat
4278  *
4279  * Description :  Once a connection from the client has been accepted,
4280  *                this function is called (via serve()) to handle the
4281  *                main business of the communication.  This function
4282  *                returns after dealing with a single request. It can
4283  *                be called multiple times with the same client socket
4284  *                if the client is keeping the connection alive.
4285  *
4286  *                The decision whether or not a client connection will
4287  *                be kept alive is up to the caller which also must
4288  *                close the client socket when done.
4289  *
4290  *                FIXME: chat is nearly thousand lines long.
4291  *                Ridiculous.
4292  *
4293  * Parameters  :
4294  *          1  :  csp = Current client state (buffers, headers, etc...)
4295  *
4296  * Returns     :  Nothing.
4297  *
4298  *********************************************************************/
4299 static void chat(struct client_state *csp)
4300 {
4301    const struct forward_spec *fwd;
4302    struct http_request *http;
4303    /* Skeleton for HTTP response, if we should intercept the request */
4304    struct http_response *rsp;
4305 #ifdef FEATURE_HTTPS_INSPECTION
4306    int use_ssl_tunnel = 0;
4307 #endif
4308
4309    http = csp->http;
4310
4311    if (receive_client_request(csp) != JB_ERR_OK)
4312    {
4313       return;
4314    }
4315
4316 #if defined(FEATURE_STATISTICS) && defined(MUTEX_LOCKS_AVAILABLE)
4317    privoxy_mutex_lock(&block_statistics_mutex);
4318    number_of_requests_received++;
4319    privoxy_mutex_unlock(&block_statistics_mutex);
4320 #endif
4321
4322    if (parse_client_request(csp) != JB_ERR_OK)
4323    {
4324       return;
4325    }
4326
4327 #ifdef FEATURE_HTTPS_INSPECTION
4328    /*
4329     * Setting flags to use old solution with SSL tunnel and to disable
4330     * certificate verification.
4331     */
4332    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION)
4333       && !cgi_page_requested(csp->http->host))
4334    {
4335       use_ssl_tunnel = 1;
4336    }
4337
4338    if (http->ssl && (csp->action->flags & ACTION_IGNORE_CERTIFICATE_ERRORS))
4339    {
4340       csp->dont_verify_certificate = 1;
4341    }
4342 #endif
4343
4344    /*
4345     * build the http request to send to the server