2870100e7f1f01076c87c8fb3f9304d670365a9c
[privoxy.git] / jcc.c
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) 2001-2020 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 # if !defined (__OS2__)
66 # include <unistd.h>
67 # include <sys/wait.h>
68 # endif /* ndef __OS2__ */
69 # include <sys/time.h>
70 # include <sys/stat.h>
71 # include <sys/ioctl.h>
72
73 #ifdef sun
74 #include <sys/termios.h>
75 #endif /* sun */
76
77 #ifdef unix
78 #include <pwd.h>
79 #include <grp.h>
80 #endif
81
82 # include <signal.h>
83
84 # ifdef __BEOS__
85 #  include <socket.h>  /* BeOS has select() for sockets only. */
86 #  include <OS.h>      /* declarations for threads and stuff. */
87 # endif
88
89 # if defined(__EMX__) || defined(__OS2__)
90 #  include <sys/select.h>  /* OS/2/EMX needs a little help with select */
91 # endif
92 # ifdef __OS2__
93 #define INCL_DOS
94 # include <os2.h>
95 # endif
96
97 #ifdef HAVE_POLL
98 #ifdef __GLIBC__
99 #include <sys/poll.h>
100 #else
101 #include <poll.h>
102 #endif /* def __GLIBC__ */
103 #else
104 # ifndef FD_ZERO
105 #  include <select.h>
106 # endif
107 #warning poll() appears to be unavailable. Your platform will become unsupported in the future.
108 #endif /* HAVE_POLL */
109
110 #endif
111
112 #include "project.h"
113 #include "list.h"
114 #include "jcc.h"
115 #ifdef FEATURE_HTTPS_INSPECTION
116 #include "ssl.h"
117 #endif
118 #include "filters.h"
119 #include "loaders.h"
120 #include "parsers.h"
121 #include "miscutil.h"
122 #include "errlog.h"
123 #include "jbsockets.h"
124 #include "gateway.h"
125 #include "actions.h"
126 #include "cgi.h"
127 #include "loadcfg.h"
128 #include "urlmatch.h"
129 #ifdef FEATURE_CLIENT_TAGS
130 #include "client-tags.h"
131 #endif
132
133 int daemon_mode = 1;
134 struct client_states clients[1];
135 struct file_list     files[1];
136
137 #ifdef FEATURE_STATISTICS
138 int urls_read     = 0;     /* total nr of urls read inc rejected */
139 int urls_rejected = 0;     /* total nr of urls rejected */
140 #endif /* def FEATURE_STATISTICS */
141
142 #ifdef FEATURE_GRACEFUL_TERMINATION
143 int g_terminate = 0;
144 #endif
145
146 #if !defined(_WIN32) && !defined(__OS2__)
147 static void sig_handler(int the_signal);
148 #endif
149 static int client_protocol_is_unsupported(const struct client_state *csp, char *req);
150 static jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers);
151 static jb_err get_server_headers(struct client_state *csp);
152 static const char *crunch_reason(const struct http_response *rsp);
153 static void send_crunch_response(struct client_state *csp, struct http_response *rsp);
154 static char *get_request_line(struct client_state *csp);
155 static jb_err receive_client_request(struct client_state *csp);
156 static jb_err parse_client_request(struct client_state *csp);
157 static void build_request_line(struct client_state *csp, const struct forward_spec *fwd, char **request_line);
158 static jb_err change_request_destination(struct client_state *csp);
159 static void chat(struct client_state *csp);
160 static void serve(struct client_state *csp);
161 #if !defined(_WIN32) || defined(_WIN_CONSOLE)
162 static void usage(const char *myname);
163 #endif
164 static void initialize_mutexes(void);
165 static jb_socket bind_port_helper(const char *haddr, int hport, int backlog);
166 static void bind_ports_helper(struct configuration_spec *config, jb_socket sockets[]);
167 static void close_ports_helper(jb_socket sockets[]);
168 static void listen_loop(void);
169 static void serve(struct client_state *csp);
170
171 #ifdef __BEOS__
172 static int32 server_thread(void *data);
173 #endif /* def __BEOS__ */
174
175 #ifdef _WIN32
176 #define sleep(N)  Sleep(((N) * 1000))
177 #endif
178
179 #ifdef __OS2__
180 #define sleep(N)  DosSleep(((N) * 100))
181 #endif
182
183 #ifdef FUZZ
184 int process_fuzzed_input(char *fuzz_input_type, char *fuzz_input_file);
185 void show_fuzz_usage(const char *name);
186 #endif
187
188 #ifdef MUTEX_LOCKS_AVAILABLE
189 /*
190  * XXX: Does the locking stuff really belong in this file?
191  */
192 privoxy_mutex_t log_mutex;
193 privoxy_mutex_t log_init_mutex;
194 privoxy_mutex_t connection_reuse_mutex;
195
196 #ifdef FEATURE_HTTPS_INSPECTION
197 privoxy_mutex_t certificate_mutex;
198 privoxy_mutex_t rng_mutex;
199 #endif
200
201 #ifdef FEATURE_EXTERNAL_FILTERS
202 privoxy_mutex_t external_filter_mutex;
203 #endif
204 #ifdef FEATURE_CLIENT_TAGS
205 privoxy_mutex_t client_tags_mutex;
206 #endif
207
208 #if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R)
209 privoxy_mutex_t resolver_mutex;
210 #endif /* !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R) */
211
212 #ifndef HAVE_GMTIME_R
213 privoxy_mutex_t gmtime_mutex;
214 #endif /* ndef HAVE_GMTIME_R */
215
216 #ifndef HAVE_LOCALTIME_R
217 privoxy_mutex_t localtime_mutex;
218 #endif /* ndef HAVE_GMTIME_R */
219
220 #if !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM)
221 privoxy_mutex_t rand_mutex;
222 #endif /* !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM) */
223
224 #endif /* def MUTEX_LOCKS_AVAILABLE */
225
226 #if defined(unix)
227 const char *basedir = NULL;
228 const char *pidfile = NULL;
229 static int received_hup_signal = 0;
230 #endif /* defined unix */
231
232 /* HTTP snipplets. */
233 static const char CSUCCEED[] =
234    "HTTP/1.1 200 Connection established\r\n\r\n";
235
236 static const char CHEADER[] =
237    "HTTP/1.1 400 Invalid header received from client\r\n"
238    "Content-Type: text/plain\r\n"
239    "Connection: close\r\n\r\n"
240    "Invalid header received from client.\r\n";
241
242 static const char FTP_RESPONSE[] =
243    "HTTP/1.1 400 Invalid request received from client\r\n"
244    "Content-Type: text/plain\r\n"
245    "Connection: close\r\n\r\n"
246    "Invalid request. Privoxy doesn't support FTP.\r\n";
247
248 static const char GOPHER_RESPONSE[] =
249    "HTTP/1.1 400 Invalid request received from client\r\n"
250    "Content-Type: text/plain\r\n"
251    "Connection: close\r\n\r\n"
252    "Invalid request. Privoxy doesn't support gopher.\r\n";
253
254 /* XXX: should be a template */
255 static const char MISSING_DESTINATION_RESPONSE[] =
256    "HTTP/1.1 400 Bad request received from client\r\n"
257    "Content-Type: text/plain\r\n"
258    "Connection: close\r\n\r\n"
259    "Bad request. Privoxy was unable to extract the destination.\r\n";
260
261 /* XXX: should be a template */
262 static const char INVALID_SERVER_HEADERS_RESPONSE[] =
263    "HTTP/1.1 502 Server or forwarder response invalid\r\n"
264    "Content-Type: text/plain\r\n"
265    "Connection: close\r\n\r\n"
266    "Bad response. The server or forwarder response doesn't look like HTTP.\r\n";
267
268 /* XXX: should be a template */
269 static const char MESSED_UP_REQUEST_RESPONSE[] =
270    "HTTP/1.1 400 Malformed request after rewriting\r\n"
271    "Content-Type: text/plain\r\n"
272    "Connection: close\r\n\r\n"
273    "Bad request. Messed up with header filters.\r\n";
274
275 static const char TOO_MANY_CONNECTIONS_RESPONSE[] =
276    "HTTP/1.1 503 Too many open connections\r\n"
277    "Content-Type: text/plain\r\n"
278    "Connection: close\r\n\r\n"
279    "Maximum number of open connections reached.\r\n";
280
281 static const char CLIENT_CONNECTION_TIMEOUT_RESPONSE[] =
282    "HTTP/1.1 504 Connection timeout\r\n"
283    "Content-Type: text/plain\r\n"
284    "Connection: close\r\n\r\n"
285    "The connection timed out because the client request didn't arrive in time.\r\n";
286
287 static const char CLIENT_BODY_PARSE_ERROR_RESPONSE[] =
288    "HTTP/1.1 400 Failed reading client body\r\n"
289    "Content-Type: text/plain\r\n"
290    "Connection: close\r\n\r\n"
291    "Failed parsing or buffering the chunk-encoded client body.\r\n";
292
293 static const char UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE[] =
294    "HTTP/1.1 417 Expecting too much\r\n"
295    "Content-Type: text/plain\r\n"
296    "Connection: close\r\n\r\n"
297    "Privoxy detected an unsupported Expect header value.\r\n";
298
299 /* A function to crunch a response */
300 typedef struct http_response *(*crunch_func_ptr)(struct client_state *);
301
302 /* Crunch function flags */
303 #define CF_NO_FLAGS        0
304 /* Cruncher applies to forced requests as well */
305 #define CF_IGNORE_FORCE    1
306 /* Crunched requests are counted for the block statistics */
307 #define CF_COUNT_AS_REJECT 2
308
309 /* A crunch function and its flags */
310 struct cruncher
311 {
312    const crunch_func_ptr cruncher;
313    const int flags;
314 };
315
316 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[]);
317
318 /* Complete list of cruncher functions */
319 static const struct cruncher crunchers_all[] = {
320    { direct_response, CF_COUNT_AS_REJECT|CF_IGNORE_FORCE},
321    { block_url,       CF_COUNT_AS_REJECT },
322 #ifdef FEATURE_TRUST
323    { trust_url,       CF_COUNT_AS_REJECT },
324 #endif /* def FEATURE_TRUST */
325    { redirect_url,    CF_NO_FLAGS  },
326    { dispatch_cgi,    CF_IGNORE_FORCE},
327    { NULL,            0 }
328 };
329
330 /* Light version, used after tags are applied */
331 static const struct cruncher crunchers_light[] = {
332    { block_url,       CF_COUNT_AS_REJECT },
333    { redirect_url,    CF_NO_FLAGS },
334    { NULL,            0 }
335 };
336
337
338 /*
339  * XXX: Don't we really mean
340  *
341  * #if defined(unix)
342  *
343  * here?
344  */
345 #if !defined(_WIN32) && !defined(__OS2__)
346 /*********************************************************************
347  *
348  * Function    :  sig_handler
349  *
350  * Description :  Signal handler for different signals.
351  *                Exit gracefully on TERM and INT
352  *                or set a flag that will cause the errlog
353  *                to be reopened by the main thread on HUP.
354  *
355  * Parameters  :
356  *          1  :  the_signal = the signal cause this function to call
357  *
358  * Returns     :  -
359  *
360  *********************************************************************/
361 static void sig_handler(int the_signal)
362 {
363    switch(the_signal)
364    {
365       case SIGTERM:
366       case SIGINT:
367          log_error(LOG_LEVEL_INFO, "exiting by signal %d .. bye", the_signal);
368 #if defined(unix)
369          if (pidfile)
370          {
371             unlink(pidfile);
372          }
373 #endif /* unix */
374          exit(the_signal);
375          break;
376
377       case SIGHUP:
378 #if defined(unix)
379          received_hup_signal = 1;
380 #endif
381          break;
382
383       default:
384          /*
385           * We shouldn't be here, unless we catch signals
386           * in main() that we can't handle here!
387           */
388          log_error(LOG_LEVEL_FATAL, "sig_handler: exiting on unexpected signal %d", the_signal);
389    }
390    return;
391
392 }
393 #endif
394
395
396 /*********************************************************************
397  *
398  * Function    :  get_write_delay
399  *
400  * Description :  Parse the delay-response parameter.
401  *
402  * Parameters  :
403  *          1  :  csp = Current client state (buffers, headers, etc...)
404  *
405  * Returns     :  Number of milliseconds to delay writes.
406  *
407  *********************************************************************/
408 static unsigned int get_write_delay(const struct client_state *csp)
409 {
410    unsigned int delay;
411    char *endptr;
412    char *newval;
413
414    if ((csp->action->flags & ACTION_DELAY_RESPONSE) == 0)
415    {
416       return 0;
417    }
418    newval = csp->action->string[ACTION_STRING_DELAY_RESPONSE];
419
420    delay = (unsigned)strtol(newval, &endptr, 0);
421    if (*endptr != '\0')
422    {
423       log_error(LOG_LEVEL_FATAL,
424          "Invalid delay-response{} parameter: '%s'", newval);
425    }
426
427    return delay;
428
429 }
430
431
432 /*********************************************************************
433  *
434  * Function    :  client_protocol_is_unsupported
435  *
436  * Description :  Checks if the client used a known unsupported
437  *                protocol and deals with it by sending an error
438  *                response.
439  *
440  * Parameters  :
441  *          1  :  csp = Current client state (buffers, headers, etc...)
442  *          2  :  req = the first request line send by the client
443  *
444  * Returns     :  TRUE if an error response has been generated, or
445  *                FALSE if the request doesn't look invalid.
446  *
447  *********************************************************************/
448 static int client_protocol_is_unsupported(const struct client_state *csp, char *req)
449 {
450    /*
451     * If it's a FTP or gopher request, we don't support it.
452     *
453     * These checks are better than nothing, but they might
454     * not work in all configurations and some clients might
455     * have problems digesting the answer.
456     *
457     * They should, however, never cause more problems than
458     * Privoxy's old behaviour (returning the misleading HTML
459     * error message:
460     *
461     * "Could not resolve http://(ftp|gopher)://example.org").
462     */
463    if (!strncmpic(req, "GET ftp://", 10) || !strncmpic(req, "GET gopher://", 13))
464    {
465       const char *response = NULL;
466       const char *protocol = NULL;
467
468       if (!strncmpic(req, "GET ftp://", 10))
469       {
470          response = FTP_RESPONSE;
471          protocol = "FTP";
472       }
473       else
474       {
475          response = GOPHER_RESPONSE;
476          protocol = "GOPHER";
477       }
478       log_error(LOG_LEVEL_ERROR,
479          "%s tried to use Privoxy as %s proxy: %s",
480          csp->ip_addr_str, protocol, req);
481       log_error(LOG_LEVEL_CLF,
482          "%s - - [%T] \"%s\" 400 0", csp->ip_addr_str, req);
483       freez(req);
484       write_socket_delayed(csp->cfd, response, strlen(response),
485          get_write_delay(csp));
486
487       return TRUE;
488    }
489
490    return FALSE;
491 }
492
493
494 /*********************************************************************
495  *
496  * Function    :  client_has_unsupported_expectations
497  *
498  * Description :  Checks if the client used an unsupported expectation
499  *                in which case an error message is delivered.
500  *
501  * Parameters  :
502  *          1  :  csp = Current client state (buffers, headers, etc...)
503  *
504  * Returns     :  TRUE if an error response has been generated, or
505  *                FALSE if the request doesn't look invalid.
506  *
507  *********************************************************************/
508 static int client_has_unsupported_expectations(const struct client_state *csp)
509 {
510    if ((csp->flags & CSP_FLAG_UNSUPPORTED_CLIENT_EXPECTATION))
511    {
512       log_error(LOG_LEVEL_ERROR,
513          "Rejecting request from client %s with unsupported Expect header value",
514          csp->ip_addr_str);
515       log_error(LOG_LEVEL_CLF,
516          "%s - - [%T] \"%s\" 417 0", csp->ip_addr_str, csp->http->cmd);
517       write_socket_delayed(csp->cfd,
518          UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE,
519          strlen(UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE),
520          get_write_delay(csp));
521
522       return TRUE;
523    }
524
525    return FALSE;
526
527 }
528
529
530 /*********************************************************************
531  *
532  * Function    :  get_request_destination_elsewhere
533  *
534  * Description :  If the client's request was redirected into
535  *                Privoxy without the client's knowledge,
536  *                the request line lacks the destination host.
537  *
538  *                This function tries to get it elsewhere,
539  *                provided accept-intercepted-requests is enabled.
540  *
541  *                "Elsewhere" currently only means "Host: header",
542  *                but in the future we may ask the redirecting
543  *                packet filter to look the destination up.
544  *
545  *                If the destination stays unknown, an error
546  *                response is send to the client and headers
547  *                are freed so that chat() can return directly.
548  *
549  * Parameters  :
550  *          1  :  csp = Current client state (buffers, headers, etc...)
551  *          2  :  headers = a header list
552  *
553  * Returns     :  JB_ERR_OK if the destination is now known, or
554  *                JB_ERR_PARSE if it isn't.
555  *
556  *********************************************************************/
557 static jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers)
558 {
559    char *req;
560
561    if (!(csp->config->feature_flags & RUNTIME_FEATURE_ACCEPT_INTERCEPTED_REQUESTS))
562    {
563       log_error(LOG_LEVEL_ERROR, "%s's request: \'%s\' is invalid."
564          " Privoxy isn't configured to accept intercepted requests.",
565          csp->ip_addr_str, csp->http->cmd);
566       /* XXX: Use correct size */
567       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
568          csp->ip_addr_str, csp->http->cmd);
569
570       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
571          get_write_delay(csp));
572       destroy_list(headers);
573
574       return JB_ERR_PARSE;
575    }
576    else if (JB_ERR_OK == get_destination_from_headers(headers, csp->http))
577    {
578 #ifndef FEATURE_EXTENDED_HOST_PATTERNS
579       /* Split the domain we just got for pattern matching */
580       init_domain_components(csp->http);
581 #endif
582
583       return JB_ERR_OK;
584    }
585    else
586    {
587       /* We can't work without destination. Go spread the news.*/
588
589       req = list_to_text(headers);
590       chomp(req);
591       /* XXX: Use correct size */
592       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
593          csp->ip_addr_str, csp->http->cmd);
594       log_error(LOG_LEVEL_ERROR,
595          "Privoxy was unable to get the destination for %s's request:\n%s\n%s",
596          csp->ip_addr_str, csp->http->cmd, req);
597       freez(req);
598
599       write_socket_delayed(csp->cfd, MISSING_DESTINATION_RESPONSE,
600          strlen(MISSING_DESTINATION_RESPONSE), get_write_delay(csp));
601       destroy_list(headers);
602
603       return JB_ERR_PARSE;
604    }
605    /*
606     * TODO: If available, use PF's ioctl DIOCNATLOOK as last resort
607     * to get the destination IP address, use it as host directly
608     * or do a reverse DNS lookup first.
609     */
610 }
611
612
613 /*********************************************************************
614  *
615  * Function    :  get_server_headers
616  *
617  * Description :  Parses server headers in iob and fills them
618  *                into csp->headers so that they can later be
619  *                handled by sed().
620  *
621  * Parameters  :
622  *          1  :  csp = Current client state (buffers, headers, etc...)
623  *
624  * Returns     :  JB_ERR_OK if everything went fine, or
625  *                JB_ERR_PARSE if the headers were incomplete.
626  *
627  *********************************************************************/
628 static jb_err get_server_headers(struct client_state *csp)
629 {
630    int continue_hack_in_da_house = 0;
631    char * header;
632
633    while (((header = get_header(csp->iob)) != NULL) || continue_hack_in_da_house)
634    {
635       if (header == NULL)
636       {
637          /*
638           * continue hack in da house. Ignore the ending of
639           * this head and continue enlisting header lines.
640           * The reason is described below.
641           */
642          enlist(csp->headers, "");
643          continue_hack_in_da_house = 0;
644          continue;
645       }
646       else if (0 == strncmpic(header, "HTTP/1.1 100", 12))
647       {
648          /*
649           * It's a bodyless continue response, don't
650           * stop header parsing after reaching its end.
651           *
652           * As a result Privoxy will concatenate the
653           * next response's head and parse and deliver
654           * the headers as if they belonged to one request.
655           *
656           * The client will separate them because of the
657           * empty line between them.
658           *
659           * XXX: What we're doing here is clearly against
660           * the intended purpose of the continue header,
661           * and under some conditions (HTTP/1.0 client request)
662           * it's a standard violation.
663           *
664           * Anyway, "sort of against the spec" is preferable
665           * to "always getting confused by Continue responses"
666           * (Privoxy's behaviour before this hack was added)
667           */
668          log_error(LOG_LEVEL_HEADER, "Continue hack in da house.");
669          continue_hack_in_da_house = 1;
670       }
671       else if (*header == '\0')
672       {
673          /*
674           * If the header is empty, but the Continue hack
675           * isn't active, we can assume that we reached the
676           * end of the buffer before we hit the end of the
677           * head.
678           *
679           * Inform the caller an let it decide how to handle it.
680           */
681          return JB_ERR_PARSE;
682       }
683
684       if (JB_ERR_MEMORY == enlist(csp->headers, header))
685       {
686          /*
687           * XXX: Should we quit the request and return a
688           * out of memory error page instead?
689           */
690          log_error(LOG_LEVEL_ERROR,
691             "Out of memory while enlisting server headers. %s lost.",
692             header);
693       }
694       freez(header);
695    }
696
697    return JB_ERR_OK;
698 }
699
700
701 /*********************************************************************
702  *
703  * Function    :  crunch_reason
704  *
705  * Description :  Translates the crunch reason code into a string.
706  *
707  * Parameters  :
708  *          1  :  rsp = a http_response
709  *
710  * Returns     :  A string with the crunch reason or an error description.
711  *
712  *********************************************************************/
713 static const char *crunch_reason(const struct http_response *rsp)
714 {
715    char * reason = NULL;
716
717    assert(rsp != NULL);
718    if (rsp == NULL)
719    {
720       return "Internal error while searching for crunch reason";
721    }
722
723    switch (rsp->crunch_reason)
724    {
725       case UNSUPPORTED:
726          reason = "Unsupported HTTP feature";
727          break;
728       case BLOCKED:
729          reason = "Blocked";
730          break;
731       case UNTRUSTED:
732          reason = "Untrusted";
733          break;
734       case REDIRECTED:
735          reason = "Redirected";
736          break;
737       case CGI_CALL:
738          reason = "CGI Call";
739          break;
740       case NO_SUCH_DOMAIN:
741          reason = "DNS failure";
742          break;
743       case FORWARDING_FAILED:
744          reason = "Forwarding failed";
745          break;
746       case CONNECT_FAILED:
747          reason = "Connection failure";
748          break;
749       case OUT_OF_MEMORY:
750          reason = "Out of memory (may mask other reasons)";
751          break;
752       case CONNECTION_TIMEOUT:
753          reason = "Connection timeout";
754          break;
755       case NO_SERVER_DATA:
756          reason = "No server data received";
757          break;
758       default:
759          reason = "No reason recorded";
760          break;
761    }
762
763    return reason;
764 }
765
766
767 /*********************************************************************
768  *
769  * Function    :  log_applied_actions
770  *
771  * Description :  Logs the applied actions if LOG_LEVEL_ACTIONS is
772  *                enabled.
773  *
774  * Parameters  :
775  *          1  :  actions = Current action spec to log
776  *
777  * Returns     :  Nothing.
778  *
779  *********************************************************************/
780 static void log_applied_actions(const struct current_action_spec *actions)
781 {
782    /*
783     * The conversion to text requires lots of memory allocations so
784     * we only do the conversion if the user is actually interested.
785     */
786    if (debug_level_is_enabled(LOG_LEVEL_ACTIONS))
787    {
788       char *actions_as_text = actions_to_line_of_text(actions);
789       log_error(LOG_LEVEL_ACTIONS, "%s", actions_as_text);
790       freez(actions_as_text);
791    }
792 }
793
794
795 /*********************************************************************
796  *
797  * Function    :  send_crunch_response
798  *
799  * Description :  Delivers already prepared response for
800  *                intercepted requests, logs the interception
801  *                and frees the response.
802  *
803  * Parameters  :
804  *          1  :  csp = Current client state (buffers, headers, etc...)
805  *          2  :  rsp = Fully prepared response. Will be freed on exit.
806  *
807  * Returns     :  Nothing.
808  *
809  *********************************************************************/
810 static void send_crunch_response(struct client_state *csp, struct http_response *rsp)
811 {
812       const struct http_request *http = csp->http;
813       char status_code[4];
814
815       assert(rsp != NULL);
816       assert(rsp->head != NULL);
817
818       if (rsp == NULL)
819       {
820          log_error(LOG_LEVEL_FATAL, "NULL response in send_crunch_response.");
821       }
822
823       /*
824        * Extract the status code from the actual head
825        * that will be send to the client. It is the only
826        * way to get it right for all requests, including
827        * the fixed ones for out-of-memory problems.
828        *
829        * A head starts like this: 'HTTP/1.1 200...'
830        *                           0123456789|11
831        *                                     10
832        */
833       status_code[0] = rsp->head[9];
834       status_code[1] = rsp->head[10];
835       status_code[2] = rsp->head[11];
836       status_code[3] = '\0';
837
838       /* Log that the request was crunched and why. */
839       log_applied_actions(csp->action);
840       log_error(LOG_LEVEL_CRUNCH, "%s: %s", crunch_reason(rsp), http->url);
841       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" %s %u",
842          csp->ip_addr_str, http->ocmd, status_code, rsp->content_length);
843
844       /* Write the answer to the client */
845 #ifdef FEATURE_HTTPS_INSPECTION
846       if (client_use_ssl(csp))
847       {
848          if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
849                  (const unsigned char *)rsp->head, rsp->head_length) < 0)
850           || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
851                  (const unsigned char *)rsp->body, rsp->content_length) < 0))
852          {
853             /* There is nothing we can do about it. */
854             log_error(LOG_LEVEL_CONNECT, "Couldn't deliver the error message "
855                "for %s through client socket %d using TLS/SSL",
856                http->url, csp->cfd);
857          }
858       }
859       else
860 #endif
861       {
862          if (write_socket_delayed(csp->cfd, rsp->head, rsp->head_length,
863                 get_write_delay(csp))
864           || write_socket_delayed(csp->cfd, rsp->body, rsp->content_length,
865                 get_write_delay(csp)))
866          {
867             /* There is nothing we can do about it. */
868             log_error(LOG_LEVEL_CONNECT,
869                "Couldn't deliver the error message for %s through client socket %d: %E",
870                http->url, csp->cfd);
871          }
872       }
873
874       /* Clean up and return */
875       if (cgi_error_memory() != rsp)
876       {
877          free_http_response(rsp);
878       }
879       return;
880 }
881
882
883 /*********************************************************************
884  *
885  * Function    :  crunch_response_triggered
886  *
887  * Description :  Checks if the request has to be crunched,
888  *                and delivers the crunch response if necessary.
889  *
890  * Parameters  :
891  *          1  :  csp = Current client state (buffers, headers, etc...)
892  *          2  :  crunchers = list of cruncher functions to run
893  *
894  * Returns     :  TRUE if the request was answered with a crunch response
895  *                FALSE otherwise.
896  *
897  *********************************************************************/
898 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[])
899 {
900    struct http_response *rsp = NULL;
901    const struct cruncher *c;
902
903    /*
904     * If CGI request crunching is disabled,
905     * check the CGI dispatcher out of order to
906     * prevent unintentional blocks or redirects.
907     */
908    if (!(csp->config->feature_flags & RUNTIME_FEATURE_CGI_CRUNCHING)
909        && (NULL != (rsp = dispatch_cgi(csp))))
910    {
911       /* Deliver, log and free the interception response. */
912       send_crunch_response(csp, rsp);
913       csp->flags |= CSP_FLAG_CRUNCHED;
914       return TRUE;
915    }
916
917    for (c = crunchers; c->cruncher != NULL; c++)
918    {
919       /*
920        * Check the cruncher if either Privoxy is toggled
921        * on and the request isn't forced, or if the cruncher
922        * applies to forced requests as well.
923        */
924       if (((csp->flags & CSP_FLAG_TOGGLED_ON) &&
925           !(csp->flags & CSP_FLAG_FORCED)) ||
926           (c->flags & CF_IGNORE_FORCE))
927       {
928          rsp = c->cruncher(csp);
929          if (NULL != rsp)
930          {
931             /* Deliver, log and free the interception response. */
932             send_crunch_response(csp, rsp);
933             csp->flags |= CSP_FLAG_CRUNCHED;
934 #ifdef FEATURE_STATISTICS
935             if (c->flags & CF_COUNT_AS_REJECT)
936             {
937                csp->flags |= CSP_FLAG_REJECTED;
938             }
939 #endif /* def FEATURE_STATISTICS */
940
941             return TRUE;
942          }
943       }
944    }
945
946    return FALSE;
947 }
948
949
950 /*********************************************************************
951  *
952  * Function    :  build_request_line
953  *
954  * Description :  Builds the HTTP request line.
955  *
956  *                If a HTTP forwarder is used it expects the whole URL,
957  *                web servers only get the path.
958  *
959  * Parameters  :
960  *          1  :  csp = Current client state (buffers, headers, etc...)
961  *          2  :  fwd = The forwarding spec used for the request
962  *                XXX: Should use http->fwd instead.
963  *          3  :  request_line = The old request line which will be replaced.
964  *
965  * Returns     :  Nothing. Terminates in case of memory problems.
966  *
967  *********************************************************************/
968 static void build_request_line(struct client_state *csp, const struct forward_spec *fwd, char **request_line)
969 {
970    struct http_request *http = csp->http;
971
972    /*
973     * Downgrade http version from 1.1 to 1.0
974     * if +downgrade action applies.
975     */
976    if ((csp->action->flags & ACTION_DOWNGRADE)
977      && (!strcmpic(http->ver, "HTTP/1.1")))
978    {
979       freez(http->ver);
980       http->ver = strdup_or_die("HTTP/1.0");
981    }
982
983    /*
984     * Rebuild the request line.
985     */
986    freez(*request_line);
987    *request_line = strdup(http->gpc);
988    string_append(request_line, " ");
989
990    if (fwd->forward_host && fwd->type != FORWARD_WEBSERVER)
991    {
992       string_append(request_line, http->url);
993    }
994    else
995    {
996       string_append(request_line, http->path);
997    }
998    string_append(request_line, " ");
999    string_append(request_line, http->ver);
1000
1001    if (*request_line == NULL)
1002    {
1003       log_error(LOG_LEVEL_FATAL, "Out of memory writing HTTP command");
1004    }
1005    log_error(LOG_LEVEL_HEADER, "New HTTP Request-Line: %s", *request_line);
1006 }
1007
1008
1009 /*********************************************************************
1010  *
1011  * Function    :  change_request_destination
1012  *
1013  * Description :  Parse a (rewritten) request line and regenerate
1014  *                the http request data.
1015  *
1016  * Parameters  :
1017  *          1  :  csp = Current client state (buffers, headers, etc...)
1018  *
1019  * Returns     :  Forwards the parse_http_request() return code.
1020  *                Terminates in case of memory problems.
1021  *
1022  *********************************************************************/
1023 static jb_err change_request_destination(struct client_state *csp)
1024 {
1025    struct http_request *http = csp->http;
1026    jb_err err;
1027
1028    log_error(LOG_LEVEL_REDIRECTS, "Rewrite detected: %s",
1029       csp->headers->first->str);
1030    free_http_request(http);
1031    err = parse_http_request(csp->headers->first->str, http);
1032    if (JB_ERR_OK != err)
1033    {
1034       log_error(LOG_LEVEL_ERROR, "Couldn't parse rewritten request: %s.",
1035          jb_err_to_string(err));
1036    }
1037
1038    return err;
1039 }
1040
1041
1042 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1043 /*********************************************************************
1044  *
1045  * Function    :  server_response_is_complete
1046  *
1047  * Description :  Determines whether we should stop reading
1048  *                from the server socket.
1049  *
1050  * Parameters  :
1051  *          1  :  csp = Current client state (buffers, headers, etc...)
1052  *          2  :  content_length = Length of content received so far.
1053  *
1054  * Returns     :  TRUE if the response is complete,
1055  *                FALSE otherwise.
1056  *
1057  *********************************************************************/
1058 static int server_response_is_complete(struct client_state *csp,
1059    unsigned long long content_length)
1060 {
1061    int content_length_known = !!(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET);
1062
1063    if (!strcmpic(csp->http->gpc, "HEAD"))
1064    {
1065       /*
1066        * "HEAD" implies no body, we are thus expecting
1067        * no content. XXX: incomplete "list" of methods?
1068        */
1069       csp->expected_content_length = 0;
1070       content_length_known = TRUE;
1071       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1072    }
1073
1074    if (csp->http->status == 204 || csp->http->status == 304)
1075    {
1076       /*
1077        * Expect no body. XXX: incomplete "list" of status codes?
1078        */
1079       csp->expected_content_length = 0;
1080       content_length_known = TRUE;
1081       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1082    }
1083
1084    return (content_length_known && ((0 == csp->expected_content_length)
1085             || (csp->expected_content_length <= content_length)));
1086 }
1087
1088
1089 #ifdef FEATURE_CONNECTION_SHARING
1090 /*********************************************************************
1091  *
1092  * Function    :  wait_for_alive_connections
1093  *
1094  * Description :  Waits for alive connections to timeout.
1095  *
1096  * Parameters  :  N/A
1097  *
1098  * Returns     :  N/A
1099  *
1100  *********************************************************************/
1101 static void wait_for_alive_connections(void)
1102 {
1103    int connections_alive = close_unusable_connections();
1104
1105    while (0 < connections_alive)
1106    {
1107       log_error(LOG_LEVEL_CONNECT,
1108          "Waiting for %d connections to timeout.",
1109          connections_alive);
1110       sleep(60);
1111       connections_alive = close_unusable_connections();
1112    }
1113
1114    log_error(LOG_LEVEL_CONNECT, "No connections to wait for left.");
1115
1116 }
1117 #endif /* def FEATURE_CONNECTION_SHARING */
1118
1119
1120 /*********************************************************************
1121  *
1122  * Function    :  save_connection_destination
1123  *
1124  * Description :  Remembers a connection for reuse later on.
1125  *
1126  * Parameters  :
1127  *          1  :  sfd  = Open socket to remember.
1128  *          2  :  http = The destination for the connection.
1129  *          3  :  fwd  = The forwarder settings used.
1130  *          4  :  server_connection  = storage.
1131  *
1132  * Returns     : void
1133  *
1134  *********************************************************************/
1135 void save_connection_destination(jb_socket sfd,
1136                                  const struct http_request *http,
1137                                  const struct forward_spec *fwd,
1138                                  struct reusable_connection *server_connection)
1139 {
1140    assert(sfd != JB_INVALID_SOCKET);
1141    assert(NULL != http->host);
1142
1143    server_connection->sfd = sfd;
1144    server_connection->host = strdup_or_die(http->host);
1145    server_connection->port = http->port;
1146
1147    assert(NULL != fwd);
1148    assert(server_connection->gateway_host == NULL);
1149    assert(server_connection->gateway_port == 0);
1150    assert(server_connection->forwarder_type == 0);
1151    assert(server_connection->forward_host == NULL);
1152    assert(server_connection->forward_port == 0);
1153
1154    server_connection->forwarder_type = fwd->type;
1155    if (NULL != fwd->gateway_host)
1156    {
1157       server_connection->gateway_host = strdup_or_die(fwd->gateway_host);
1158    }
1159    else
1160    {
1161       server_connection->gateway_host = NULL;
1162    }
1163    server_connection->gateway_port = fwd->gateway_port;
1164
1165    if (NULL != fwd->forward_host)
1166    {
1167       server_connection->forward_host = strdup_or_die(fwd->forward_host);
1168    }
1169    else
1170    {
1171       server_connection->forward_host = NULL;
1172    }
1173    server_connection->forward_port = fwd->forward_port;
1174 }
1175
1176
1177 /*********************************************************************
1178  *
1179  * Function    : verify_request_length
1180  *
1181  * Description : Checks if we already got the whole client requests
1182  *               and sets CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ if
1183  *               we do.
1184  *
1185  *               Data that doesn't belong to the current request is
1186  *               either thrown away to let the client retry on a clean
1187  *               socket, or stashed to be dealt with after the current
1188  *               request is served.
1189  *
1190  * Parameters  :
1191  *          1  :  csp = Current client state (buffers, headers, etc...)
1192  *
1193  * Returns     :  void
1194  *
1195  *********************************************************************/
1196 static void verify_request_length(struct client_state *csp)
1197 {
1198    unsigned long long buffered_request_bytes =
1199       (unsigned long long)(csp->client_iob->eod - csp->client_iob->cur);
1200
1201    if ((csp->expected_client_content_length != 0)
1202       && (buffered_request_bytes != 0))
1203    {
1204       if (csp->expected_client_content_length >= buffered_request_bytes)
1205       {
1206          csp->expected_client_content_length -= buffered_request_bytes;
1207          log_error(LOG_LEVEL_CONNECT, "Reduced expected bytes to %llu "
1208             "to account for the %llu ones we already got.",
1209             csp->expected_client_content_length, buffered_request_bytes);
1210       }
1211       else
1212       {
1213          assert(csp->client_iob->eod > csp->client_iob->cur + csp->expected_client_content_length);
1214          csp->client_iob->eod = csp->client_iob->cur + csp->expected_client_content_length;
1215          log_error(LOG_LEVEL_CONNECT, "Reducing expected bytes to 0. "
1216             "Marking the server socket tainted after throwing %llu bytes away.",
1217             buffered_request_bytes - csp->expected_client_content_length);
1218          csp->expected_client_content_length = 0;
1219          csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1220       }
1221
1222       if (csp->expected_client_content_length == 0)
1223       {
1224          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1225       }
1226    }
1227
1228    if (!(csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ)
1229       && ((csp->client_iob->cur < csp->client_iob->eod)
1230          || (csp->expected_client_content_length != 0)))
1231    {
1232       if (strcmpic(csp->http->gpc, "GET")
1233          && strcmpic(csp->http->gpc, "HEAD")
1234          && strcmpic(csp->http->gpc, "TRACE")
1235          && strcmpic(csp->http->gpc, "OPTIONS")
1236          && strcmpic(csp->http->gpc, "DELETE"))
1237       {
1238          /* XXX: this is an incomplete hack */
1239          csp->flags &= ~CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1240          log_error(LOG_LEVEL_CONNECT, "There better be a request body.");
1241       }
1242       else
1243       {
1244          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1245
1246          if ((csp->config->feature_flags & RUNTIME_FEATURE_TOLERATE_PIPELINING) == 0)
1247          {
1248             csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1249             log_error(LOG_LEVEL_CONNECT,
1250                "Possible pipeline attempt detected. The connection will not "
1251                "be kept alive and we will only serve the first request.");
1252             /* Nuke the pipelined requests from orbit, just to be sure. */
1253             clear_iob(csp->client_iob);
1254          }
1255          else
1256          {
1257             /*
1258              * Keep the pipelined data around for now, we'll deal with
1259              * it once we're done serving the current request.
1260              */
1261             csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
1262             assert(csp->client_iob->eod >= csp->client_iob->cur);
1263             log_error(LOG_LEVEL_CONNECT, "Complete client request followed by "
1264                "%d bytes of pipelined data received.",
1265                (int)(csp->client_iob->eod - csp->client_iob->cur));
1266          }
1267       }
1268    }
1269    else
1270    {
1271       csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1272       log_error(LOG_LEVEL_CONNECT, "Complete client request received.");
1273    }
1274 }
1275 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1276
1277
1278 /*********************************************************************
1279  *
1280  * Function    :  mark_server_socket_tainted
1281  *
1282  * Description :  Makes sure we don't reuse a server socket
1283  *                (if we didn't read everything the server sent
1284  *                us reusing the socket would lead to garbage).
1285  *
1286  * Parameters  :
1287  *          1  :  csp = Current client state (buffers, headers, etc...)
1288  *
1289  * Returns     :  void.
1290  *
1291  *********************************************************************/
1292 static void mark_server_socket_tainted(struct client_state *csp)
1293 {
1294    /*
1295     * For consistency we always mark the server socket
1296     * tainted, however, to reduce the log noise we only
1297     * emit a log message if the server socket could have
1298     * actually been reused.
1299     */
1300    if ((csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE)
1301       && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
1302    {
1303       log_error(LOG_LEVEL_CONNECT,
1304          "Marking the server socket %d tainted.",
1305          csp->server_connection.sfd);
1306    }
1307    csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1308 }
1309
1310 /*********************************************************************
1311  *
1312  * Function    :  get_request_line
1313  *
1314  * Description : Read the client request line.
1315  *
1316  * Parameters  :
1317  *          1  :  csp = Current client state (buffers, headers, etc...)
1318  *
1319  * Returns     :  Pointer to request line or NULL in case of errors.
1320  *
1321  *********************************************************************/
1322 static char *get_request_line(struct client_state *csp)
1323 {
1324    char buf[BUFFER_SIZE];
1325    char *request_line = NULL;
1326    int len;
1327
1328    memset(buf, 0, sizeof(buf));
1329
1330    if ((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) != 0)
1331    {
1332       /*
1333        * If there are multiple pipelined requests waiting,
1334        * the flag will be set again once the next request
1335        * has been parsed.
1336        */
1337       csp->flags &= ~CSP_FLAG_PIPELINED_REQUEST_WAITING;
1338
1339       request_line = get_header(csp->client_iob);
1340       if ((NULL != request_line) && ('\0' != *request_line))
1341       {
1342          return request_line;
1343       }
1344       else
1345       {
1346          log_error(LOG_LEVEL_CONNECT, "No complete request line "
1347             "received yet. Continuing reading from %d.", csp->cfd);
1348       }
1349    }
1350
1351    do
1352    {
1353       if (
1354 #ifdef FUZZ
1355           0 == (csp->flags & CSP_FLAG_FUZZED_INPUT) &&
1356 #endif
1357           !data_is_available(csp->cfd, csp->config->socket_timeout)
1358           )
1359       {
1360          if (socket_is_still_alive(csp->cfd))
1361          {
1362             log_error(LOG_LEVEL_CONNECT,
1363                "No request line on socket %d received in time. Timeout: %d.",
1364                csp->cfd, csp->config->socket_timeout);
1365             write_socket_delayed(csp->cfd, CLIENT_CONNECTION_TIMEOUT_RESPONSE,
1366                strlen(CLIENT_CONNECTION_TIMEOUT_RESPONSE),
1367                get_write_delay(csp));
1368          }
1369          else
1370          {
1371             log_error(LOG_LEVEL_CONNECT,
1372                "The client side of the connection on socket %d got "
1373                "closed without sending a complete request line.", csp->cfd);
1374          }
1375          return NULL;
1376       }
1377
1378       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1379
1380       if (len <= 0) return NULL;
1381
1382       /*
1383        * If there is no memory left for buffering the
1384        * request, there is nothing we can do but hang up
1385        */
1386       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1387       {
1388          return NULL;
1389       }
1390
1391       request_line = get_header(csp->client_iob);
1392
1393    } while ((NULL != request_line) && ('\0' == *request_line));
1394
1395    return request_line;
1396
1397 }
1398
1399 enum chunk_status
1400 {
1401    CHUNK_STATUS_MISSING_DATA,
1402    CHUNK_STATUS_BODY_COMPLETE,
1403    CHUNK_STATUS_PARSE_ERROR
1404 };
1405
1406
1407 /*********************************************************************
1408  *
1409  * Function    :  chunked_body_is_complete
1410  *
1411  * Description :  Figures out whether or not a chunked body is complete.
1412  *
1413  *                Currently it always starts at the beginning of the
1414  *                buffer which is somewhat wasteful and prevents Privoxy
1415  *                from starting to forward the correctly parsed chunks
1416  *                as soon as theoretically possible.
1417  *
1418  *                Should be modified to work with a common buffer,
1419  *                and allow the caller to skip already parsed chunks.
1420  *
1421  *                This would allow the function to be used for unbuffered
1422  *                response bodies as well.
1423  *
1424  * Parameters  :
1425  *          1  :  iob = Buffer with the body to check.
1426  *          2  :  length = Length of complete body
1427  *
1428  * Returns     :  Enum with the result of the check.
1429  *
1430  *********************************************************************/
1431 static enum chunk_status chunked_body_is_complete(struct iob *iob, size_t *length)
1432 {
1433    unsigned int chunksize;
1434    char *p = iob->cur;
1435
1436    do
1437    {
1438       /*
1439        * We need at least a single digit, followed by "\r\n",
1440        * followed by an unknown amount of data, followed by "\r\n".
1441        */
1442       if (p + 5 > iob->eod)
1443       {
1444          return CHUNK_STATUS_MISSING_DATA;
1445       }
1446       if (sscanf(p, "%x", &chunksize) != 1)
1447       {
1448          return CHUNK_STATUS_PARSE_ERROR;
1449       }
1450
1451       /*
1452        * We want at least a single digit, followed by "\r\n",
1453        * followed by the specified amount of data, followed by "\r\n".
1454        */
1455       if (p + chunksize + 5 > iob->eod)
1456       {
1457          return CHUNK_STATUS_MISSING_DATA;
1458       }
1459
1460       /* Skip chunk-size. */
1461       p = strstr(p, "\r\n");
1462       if (NULL == p)
1463       {
1464          return CHUNK_STATUS_PARSE_ERROR;
1465       }
1466       /* Move beyond the chunkdata. */
1467       p += 2 + chunksize;
1468
1469       /* There should be another "\r\n" to skip */
1470       if (memcmp(p, "\r\n", 2))
1471       {
1472          return CHUNK_STATUS_PARSE_ERROR;
1473       }
1474       p += 2;
1475    } while (chunksize > 0U);
1476
1477    *length = (size_t)(p - iob->cur);
1478    assert(*length <= (size_t)(iob->eod - iob->cur));
1479    assert(p <= iob->eod);
1480
1481    return CHUNK_STATUS_BODY_COMPLETE;
1482
1483 }
1484
1485
1486 /*********************************************************************
1487  *
1488  * Function    : receive_chunked_client_request_body
1489  *
1490  * Description : Read the chunk-encoded client request body.
1491  *               Failures are dealt with.
1492  *
1493  * Parameters  :
1494  *          1  :  csp = Current client state (buffers, headers, etc...)
1495  *
1496  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1497  *
1498  *********************************************************************/
1499 static jb_err receive_chunked_client_request_body(struct client_state *csp)
1500 {
1501    size_t body_length;
1502    enum chunk_status status;
1503
1504    while (CHUNK_STATUS_MISSING_DATA ==
1505       (status = chunked_body_is_complete(csp->client_iob, &body_length)))
1506    {
1507       char buf[BUFFER_SIZE];
1508       int len;
1509
1510       if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1511       {
1512          log_error(LOG_LEVEL_ERROR,
1513             "Timeout while waiting for the client body.");
1514          break;
1515       }
1516       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1517       if (len <= 0)
1518       {
1519          log_error(LOG_LEVEL_ERROR, "Read the client body failed: %E");
1520          break;
1521       }
1522       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1523       {
1524          break;
1525       }
1526    }
1527    if (status != CHUNK_STATUS_BODY_COMPLETE)
1528    {
1529       write_socket_delayed(csp->cfd, CLIENT_BODY_PARSE_ERROR_RESPONSE,
1530          strlen(CLIENT_BODY_PARSE_ERROR_RESPONSE), get_write_delay(csp));
1531       log_error(LOG_LEVEL_CLF,
1532          "%s - - [%T] \"Failed reading chunked client body\" 400 0", csp->ip_addr_str);
1533       return JB_ERR_PARSE;
1534    }
1535    log_error(LOG_LEVEL_CONNECT,
1536       "Chunked client body completely read. Length: %d", body_length);
1537    csp->expected_client_content_length = body_length;
1538
1539    return JB_ERR_OK;
1540
1541 }
1542
1543
1544 #ifdef FUZZ
1545 /*********************************************************************
1546  *
1547  * Function    :  fuzz_chunked_transfer_encoding
1548  *
1549  * Description :  Treat the fuzzed input as chunked transfer encoding
1550  *                to check and dechunk.
1551  *
1552  * Parameters  :
1553  *          1  :  csp      = Used to store the data.
1554  *          2  :  fuzz_input_file = File to read the input from.
1555  *
1556  * Returns     : Result of dechunking
1557  *
1558  *********************************************************************/
1559 extern int fuzz_chunked_transfer_encoding(struct client_state *csp, char *fuzz_input_file)
1560 {
1561    size_t length;
1562    size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
1563    enum chunk_status status;
1564
1565    status = chunked_body_is_complete(csp->iob, &length);
1566    if (CHUNK_STATUS_BODY_COMPLETE != status)
1567    {
1568       log_error(LOG_LEVEL_INFO, "Chunked body is incomplete or invalid");
1569    }
1570
1571    return (JB_ERR_OK == remove_chunked_transfer_coding(csp->iob->cur, &size));
1572
1573 }
1574
1575
1576 /*********************************************************************
1577  *
1578  * Function    : fuzz_client_request
1579  *
1580  * Description : Try to get a client request from the fuzzed input.
1581  *
1582  * Parameters  :
1583  *          1  :  csp = Current client state (buffers, headers, etc...)
1584  *          2  :  fuzz_input_file = File to read the input from.
1585  *
1586  * Returns     :  Result of fuzzing.
1587  *
1588  *********************************************************************/
1589 extern int fuzz_client_request(struct client_state *csp, char *fuzz_input_file)
1590 {
1591    jb_err err;
1592
1593    csp->cfd = 0;
1594    csp->ip_addr_str = "fuzzer";
1595
1596    if (strcmp(fuzz_input_file, "-") != 0)
1597    {
1598       log_error(LOG_LEVEL_FATAL,
1599          "Fuzzed client requests can currenty only be read from stdin (-).");
1600    }
1601    err = receive_client_request(csp);
1602    if (err != JB_ERR_OK)
1603    {
1604       return 1;
1605    }
1606    err = parse_client_request(csp);
1607    if (err != JB_ERR_OK)
1608    {
1609       return 1;
1610    }
1611
1612    return 0;
1613
1614 }
1615 #endif  /* def FUZZ */
1616
1617
1618 #ifdef FEATURE_FORCE_LOAD
1619 /*********************************************************************
1620  *
1621  * Function    :  force_required
1622  *
1623  * Description : Checks a request line to see if it contains
1624  *               the FORCE_PREFIX. If it does, it is removed
1625  *               unless enforcing requests has beend disabled.
1626  *
1627  * Parameters  :
1628  *          1  :  request_line = HTTP request line
1629  *
1630  * Returns     :  TRUE if force is required, FALSE otherwise.
1631  *
1632  *********************************************************************/
1633 static int force_required(const struct client_state *csp, char *request_line)
1634 {
1635    char *p;
1636
1637    p = strstr(request_line, "http://");
1638    if (p != NULL)
1639    {
1640       /* Skip protocol */
1641       p += strlen("http://");
1642    }
1643    else
1644    {
1645       /* Intercepted request usually don't specify the protocol. */
1646       p = request_line;
1647    }
1648
1649    /* Go to the beginning of the path */
1650    p = strstr(p, "/");
1651    if (p == NULL)
1652    {
1653       /*
1654        * If the path is missing the request line is invalid and we
1655        * are done here. The client-visible rejection happens later on.
1656        */
1657       return 0;
1658    }
1659
1660    if (0 == strncmpic(p, FORCE_PREFIX, strlen(FORCE_PREFIX) - 1))
1661    {
1662       if (!(csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS))
1663       {
1664          /* XXX: Should clean more carefully */
1665          strclean(request_line, FORCE_PREFIX);
1666          log_error(LOG_LEVEL_FORCE,
1667             "Enforcing request: \"%s\".", request_line);
1668
1669          return 1;
1670       }
1671       log_error(LOG_LEVEL_FORCE,
1672          "Ignored force prefix in request: \"%s\".", request_line);
1673    }
1674
1675    return 0;
1676
1677 }
1678 #endif /* def FEATURE_FORCE_LOAD */
1679
1680
1681 /*********************************************************************
1682  *
1683  * Function    :  receive_client_request
1684  *
1685  * Description : Read the client's request (more precisely the
1686  *               client headers) and answer it if necessary.
1687  *
1688  * Parameters  :
1689  *          1  :  csp = Current client state (buffers, headers, etc...)
1690  *
1691  * Returns     :  JB_ERR_OK, JB_ERR_PARSE or JB_ERR_MEMORY
1692  *
1693  *********************************************************************/
1694 static jb_err receive_client_request(struct client_state *csp)
1695 {
1696    char buf[BUFFER_SIZE];
1697    char *p;
1698    char *req = NULL;
1699    struct http_request *http;
1700    int len;
1701    jb_err err;
1702
1703    /* Temporary copy of the client's headers before they get enlisted in csp->headers */
1704    struct list header_list;
1705    struct list *headers = &header_list;
1706
1707    /* We don't care if the arriving data is a valid HTTP request or not. */
1708    csp->requests_received_total++;
1709
1710    http = csp->http;
1711
1712    memset(buf, 0, sizeof(buf));
1713
1714    req = get_request_line(csp);
1715    if (req == NULL)
1716    {
1717       mark_server_socket_tainted(csp);
1718       return JB_ERR_PARSE;
1719    }
1720    assert(*req != '\0');
1721
1722    if (client_protocol_is_unsupported(csp, req))
1723    {
1724       return JB_ERR_PARSE;
1725    }
1726
1727 #ifdef FEATURE_FORCE_LOAD
1728    if (force_required(csp, req))
1729    {
1730       csp->flags |= CSP_FLAG_FORCED;
1731    }
1732 #endif /* def FEATURE_FORCE_LOAD */
1733
1734    err = parse_http_request(req, http);
1735    freez(req);
1736    if (JB_ERR_OK != err)
1737    {
1738       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
1739          get_write_delay(csp));
1740       /* XXX: Use correct size */
1741       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
1742       log_error(LOG_LEVEL_ERROR,
1743          "Couldn't parse request line received from %s: %s",
1744          csp->ip_addr_str, jb_err_to_string(err));
1745
1746       free_http_request(http);
1747       return JB_ERR_PARSE;
1748    }
1749
1750    /* grab the rest of the client's headers */
1751    init_list(headers);
1752    for (;;)
1753    {
1754       p = get_header(csp->client_iob);
1755
1756       if (p == NULL)
1757       {
1758          /* There are no additional headers to read. */
1759          break;
1760       }
1761
1762       if (*p == '\0')
1763       {
1764          /*
1765           * We didn't receive a complete header
1766           * line yet, get the rest of it.
1767           */
1768          if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1769          {
1770             log_error(LOG_LEVEL_ERROR,
1771                "Stopped grabbing the client headers.");
1772             destroy_list(headers);
1773             return JB_ERR_PARSE;
1774          }
1775
1776          len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1777          if (len <= 0)
1778          {
1779             log_error(LOG_LEVEL_ERROR, "read from client failed: %E");
1780             destroy_list(headers);
1781             return JB_ERR_PARSE;
1782          }
1783
1784          if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1785          {
1786             /*
1787              * If there is no memory left for buffering the
1788              * request, there is nothing we can do but hang up
1789              */
1790             destroy_list(headers);
1791             return JB_ERR_MEMORY;
1792          }
1793       }
1794       else
1795       {
1796          if (!strncmpic(p, "Transfer-Encoding:", 18))
1797          {
1798             /*
1799              * XXX: should be called through sed()
1800              *      but currently can't.
1801              */
1802             client_transfer_encoding(csp, &p);
1803          }
1804          /*
1805           * We were able to read a complete
1806           * header and can finally enlist it.
1807           */
1808          enlist(headers, p);
1809          freez(p);
1810       }
1811    }
1812
1813    if (http->host == NULL)
1814    {
1815       /*
1816        * If we still don't know the request destination,
1817        * the request is invalid or the client uses
1818        * Privoxy without its knowledge.
1819        */
1820       if (JB_ERR_OK != get_request_destination_elsewhere(csp, headers))
1821       {
1822          /*
1823           * Our attempts to get the request destination
1824           * elsewhere failed or Privoxy is configured
1825           * to only accept proxy requests.
1826           *
1827           * An error response has already been send
1828           * and we're done here.
1829           */
1830          return JB_ERR_PARSE;
1831       }
1832    }
1833
1834 #ifdef FEATURE_CLIENT_TAGS
1835    /* XXX: If the headers were enlisted sooner, passing csp would do. */
1836    set_client_address(csp, headers);
1837    get_tag_list_for_client(csp->client_tags, csp->client_address);
1838 #endif
1839
1840    /*
1841     * Determine the actions for this URL
1842     */
1843 #ifdef FEATURE_TOGGLE
1844    if (!(csp->flags & CSP_FLAG_TOGGLED_ON))
1845    {
1846       /* Most compatible set of actions (i.e. none) */
1847       init_current_action(csp->action);
1848    }
1849    else
1850 #endif /* ndef FEATURE_TOGGLE */
1851    {
1852       get_url_actions(csp, http);
1853    }
1854
1855    enlist(csp->headers, http->cmd);
1856
1857    /* Append the previously read headers */
1858    err = list_append_list_unique(csp->headers, headers);
1859    destroy_list(headers);
1860
1861    return err;
1862
1863 }
1864
1865
1866 /*********************************************************************
1867  *
1868  * Function    : parse_client_request
1869  *
1870  * Description : Parses the client's request and decides what to do
1871  *               with it.
1872  *
1873  *               Note that since we're not using select() we could get
1874  *               blocked here if a client connected, then didn't say
1875  *               anything!
1876  *
1877  * Parameters  :
1878  *          1  :  csp = Current client state (buffers, headers, etc...)
1879  *
1880  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1881  *
1882  *********************************************************************/
1883 static jb_err parse_client_request(struct client_state *csp)
1884 {
1885    struct http_request *http = csp->http;
1886    jb_err err;
1887
1888 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1889    if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
1890     && (!strcmpic(csp->http->ver, "HTTP/1.1"))
1891     && (csp->http->ssl == 0))
1892    {
1893       /* Assume persistence until further notice */
1894       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1895    }
1896
1897    if (csp->http->ssl == 0)
1898    {
1899       /*
1900        * This whole block belongs to chat() but currently
1901        * has to be executed before sed().
1902        */
1903       if (csp->flags & CSP_FLAG_CHUNKED_CLIENT_BODY)
1904       {
1905          if (receive_chunked_client_request_body(csp) != JB_ERR_OK)
1906          {
1907             return JB_ERR_PARSE;
1908          }
1909       }
1910       else
1911       {
1912          csp->expected_client_content_length = get_expected_content_length(csp->headers);
1913       }
1914       verify_request_length(csp);
1915    }
1916    else
1917    {
1918       csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1919    }
1920 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1921
1922    err = sed(csp, FILTER_CLIENT_HEADERS);
1923    if (JB_ERR_OK != err)
1924    {
1925       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
1926          csp->ip_addr_str);
1927       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
1928          csp->ip_addr_str, csp->http->cmd);
1929       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER), get_write_delay(csp));
1930       return JB_ERR_PARSE;
1931    }
1932    csp->flags |= CSP_FLAG_CLIENT_HEADER_PARSING_DONE;
1933
1934    /* Check request line for rewrites. */
1935    if ((NULL == csp->headers->first->str)
1936       || (strcmp(http->cmd, csp->headers->first->str) &&
1937          (JB_ERR_OK != change_request_destination(csp))))
1938    {
1939       /*
1940        * A header filter broke the request line - bail out.
1941        */
1942       write_socket_delayed(csp->cfd, MESSED_UP_REQUEST_RESPONSE,
1943          strlen(MESSED_UP_REQUEST_RESPONSE), get_write_delay(csp));
1944       /* XXX: Use correct size */
1945       log_error(LOG_LEVEL_CLF,
1946          "%s - - [%T] \"Invalid request generated\" 500 0", csp->ip_addr_str);
1947       log_error(LOG_LEVEL_ERROR,
1948          "Invalid request line after applying header filters.");
1949       free_http_request(http);
1950
1951       return JB_ERR_PARSE;
1952    }
1953
1954    if (client_has_unsupported_expectations(csp))
1955    {
1956       return JB_ERR_PARSE;
1957    }
1958
1959    return JB_ERR_OK;
1960
1961 }
1962
1963
1964 /*********************************************************************
1965  *
1966  * Function    : send_http_request
1967  *
1968  * Description : Sends the HTTP headers from the client request
1969  *               and all the body data that has already been received.
1970  *
1971  * Parameters  :
1972  *          1  :  csp = Current client state (buffers, headers, etc...)
1973  *
1974  * Returns     :  0 on success, anything else is an error.
1975  *
1976  *********************************************************************/
1977 static int send_http_request(struct client_state *csp)
1978 {
1979    char *hdr;
1980    int write_failure;
1981
1982    hdr = list_to_text(csp->headers);
1983    if (hdr == NULL)
1984    {
1985       /* FIXME Should handle error properly */
1986       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header");
1987    }
1988    list_remove_all(csp->headers);
1989
1990    /*
1991     * Write the client's (modified) header to the server
1992     * (along with anything else that may be in the buffer)
1993     */
1994    write_failure = 0 != write_socket(csp->server_connection.sfd, hdr, strlen(hdr));
1995    freez(hdr);
1996
1997    if (write_failure)
1998    {
1999       log_error(LOG_LEVEL_CONNECT, "Failed sending request headers to: %s: %E",
2000          csp->http->hostport);
2001    }
2002    else if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2003       && (flush_iob(csp->server_connection.sfd, csp->client_iob, 0) < 0))
2004    {
2005       write_failure = 1;
2006       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2007          csp->http->hostport);
2008    }
2009
2010    return write_failure;
2011
2012 }
2013
2014
2015 #ifdef FEATURE_HTTPS_INSPECTION
2016 /*********************************************************************
2017  *
2018  * Function    : receive_and_send_encrypted_post_data
2019  *
2020  * Description : Reads remaining POST data from the client and sends
2021  *               it to the server.
2022  *
2023  * Parameters  :
2024  *          1  :  csp = Current client state (buffers, headers, etc...)
2025  *
2026  * Returns     :  0 on success, anything else is an error.
2027  *
2028  *********************************************************************/
2029 static jb_err receive_and_send_encrypted_post_data(struct client_state *csp)
2030 {
2031    int content_length_known = csp->expected_client_content_length != 0;
2032
2033    while (is_ssl_pending(&(csp->mbedtls_client_attr.ssl)))
2034    {
2035       unsigned char buf[BUFFER_SIZE];
2036       int len;
2037       int max_bytes_to_read = sizeof(buf);
2038
2039       if (content_length_known && csp->expected_client_content_length < sizeof(buf))
2040       {
2041          max_bytes_to_read = (int)csp->expected_client_content_length;
2042       }
2043       log_error(LOG_LEVEL_CONNECT,
2044          "Waiting for up to %d bytes of POST data from the client.",
2045          max_bytes_to_read);
2046       len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl), buf,
2047          (unsigned)max_bytes_to_read);
2048       if (len == -1)
2049       {
2050          return 1;
2051       }
2052       if (len == 0)
2053       {
2054          /* XXX: Does this actually happen? */
2055          break;
2056       }
2057       log_error(LOG_LEVEL_HEADER, "Forwarding %d bytes of encrypted POST data",
2058          len);
2059       len = ssl_send_data(&(csp->mbedtls_server_attr.ssl), buf, (size_t)len);
2060       if (len == -1)
2061       {
2062          return 1;
2063       }
2064       if (csp->expected_client_content_length != 0)
2065       {
2066          if (csp->expected_client_content_length >= len)
2067          {
2068             csp->expected_client_content_length -= (unsigned)len;
2069          }
2070          if (csp->expected_client_content_length == 0)
2071          {
2072             log_error(LOG_LEVEL_HEADER, "Forwarded the last %d bytes", len);
2073             break;
2074          }
2075       }
2076    }
2077
2078    log_error(LOG_LEVEL_HEADER, "Done forwarding encrypted POST data");
2079
2080    return 0;
2081
2082 }
2083
2084
2085 /*********************************************************************
2086  *
2087  * Function    : send_https_request
2088  *
2089  * Description : Sends the HTTP headers from the client request
2090  *               and all the body data that has already been received.
2091  *
2092  * Parameters  :
2093  *          1  :  csp = Current client state (buffers, headers, etc...)
2094  *
2095  * Returns     :  0 on success, anything else is an error.
2096  *
2097  *********************************************************************/
2098 static int send_https_request(struct client_state *csp)
2099 {
2100    char *hdr;
2101    int ret;
2102    long flushed = 0;
2103
2104    hdr = list_to_text(csp->https_headers);
2105    if (hdr == NULL)
2106    {
2107       /* FIXME Should handle error properly */
2108       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header");
2109    }
2110    list_remove_all(csp->https_headers);
2111
2112    /*
2113     * Write the client's (modified) header to the server
2114     * (along with anything else that may be in the buffer)
2115     */
2116    ret = ssl_send_data(&(csp->mbedtls_server_attr.ssl),
2117       (const unsigned char *)hdr, strlen(hdr));
2118    freez(hdr);
2119
2120    if (ret < 0)
2121    {
2122       log_error(LOG_LEVEL_CONNECT,
2123          "Failed sending encrypted request headers to: %s: %E",
2124          csp->http->hostport);
2125       mark_server_socket_tainted(csp);
2126       close_client_and_server_ssl_connections(csp);
2127       return 1;
2128    }
2129
2130    if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2131       && ((flushed = ssl_flush_socket(&(csp->mbedtls_server_attr.ssl),
2132             csp->client_iob)) < 0))
2133    {
2134       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2135          csp->http->hostport);
2136       return 1;
2137    }
2138    if (flushed != 0)
2139    {
2140       if (csp->expected_client_content_length != 0)
2141       {
2142          if (csp->expected_client_content_length < flushed)
2143          {
2144             log_error(LOG_LEVEL_ERROR,
2145                "Flushed %d bytes of request body while only expecting %llu",
2146                flushed, csp->expected_client_content_length);
2147             csp->expected_client_content_length = 0;
2148          }
2149          else
2150          {
2151             log_error(LOG_LEVEL_CONNECT,
2152                "Flushed %d bytes of request body while expecting %llu",
2153                flushed, csp->expected_client_content_length);
2154             csp->expected_client_content_length -= (unsigned)flushed;
2155             if (receive_and_send_encrypted_post_data(csp))
2156             {
2157                return 1;
2158             }
2159          }
2160       }
2161       else
2162       {
2163          log_error(LOG_LEVEL_CONNECT,
2164             "Flushed %d bytes of request body", flushed);
2165       }
2166    }
2167
2168    log_error(LOG_LEVEL_CONNECT, "Encrypted request sent");
2169
2170    return 0;
2171
2172 }
2173
2174
2175 /*********************************************************************
2176  *
2177  * Function    :  receive_encrypted_request
2178  *
2179  * Description :  Receives an encrypted request.
2180  *
2181  * Parameters  :
2182  *          1  :  csp = Current client state (buffers, headers, etc...)
2183  *
2184  * Returns     :  JB_ERR_OK on success,
2185  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2186  *
2187  *********************************************************************/
2188 static jb_err receive_encrypted_request(struct client_state *csp)
2189 {
2190    char buf[BUFFER_SIZE];
2191    int len;
2192    char *p;
2193
2194    do
2195    {
2196       log_error(LOG_LEVEL_HEADER, "Reading encrypted headers");
2197       if (!data_is_available(csp->cfd, (int)csp->config->keep_alive_timeout))
2198       {
2199          log_error(LOG_LEVEL_CONNECT,
2200             "Socket %d timed out while waiting for client headers", csp->cfd);
2201          return JB_ERR_PARSE;
2202       }
2203       len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl),
2204          (unsigned char *)buf, sizeof(buf));
2205       if (len == -1)
2206       {
2207          return JB_ERR_PARSE;
2208       }
2209       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
2210       {
2211          return JB_ERR_MEMORY;
2212       }
2213       p = strstr(csp->client_iob->cur, "\r\n\r\n");
2214    } while (p == NULL);
2215
2216    log_error(LOG_LEVEL_HEADER, "Encrypted headers received completely");
2217
2218    return JB_ERR_OK;
2219 }
2220
2221
2222 /*********************************************************************
2223  *
2224  * Function    :  process_encrypted_request
2225  *
2226  * Description :  Receives and parses an encrypted request.
2227  *
2228  * Parameters  :
2229  *          1  :  csp = Current client state (buffers, headers, etc...)
2230  *
2231  * Returns     :  JB_ERR_OK on success,
2232  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2233  *
2234  *********************************************************************/
2235 static jb_err process_encrypted_request(struct client_state *csp)
2236 {
2237    char *p;
2238    char *request_line;
2239    jb_err err;
2240    /* Temporary copy of the client's headers before they get enlisted in csp->https_headers */
2241    struct list header_list;
2242    struct list *headers = &header_list;
2243
2244    err = receive_encrypted_request(csp);
2245    if (err != JB_ERR_OK)
2246    {
2247       /* XXX: Also used for JB_ERR_MEMORY */
2248       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2249          (const unsigned char *)CHEADER, strlen(CHEADER));
2250       return err;
2251    }
2252
2253    /* We don't need get_request_line() because the whole HTTP head is buffered. */
2254    request_line = get_header(csp->client_iob);
2255    if (request_line == NULL)
2256    {
2257       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2258          (const unsigned char *)CHEADER, strlen(CHEADER));
2259       return JB_ERR_PARSE;
2260    }
2261    assert(*request_line != '\0');
2262
2263    if (client_protocol_is_unsupported(csp, request_line))
2264    {
2265       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2266          (const unsigned char *)CHEADER, strlen(CHEADER));
2267       return JB_ERR_PARSE;
2268    }
2269
2270 #ifdef FEATURE_FORCE_LOAD
2271    if (force_required(csp, request_line))
2272    {
2273       csp->flags |= CSP_FLAG_FORCED;
2274    }
2275 #endif /* def FEATURE_FORCE_LOAD */
2276
2277    free_http_request(csp->http);
2278
2279    err = parse_http_request(request_line, csp->http);
2280    /* XXX: Restore ssl setting. This is ugly */
2281    csp->http->client_ssl = 1;
2282    csp->http->server_ssl = 1;
2283
2284    freez(request_line);
2285    if (JB_ERR_OK != err)
2286    {
2287       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2288          (const unsigned char *)CHEADER, strlen(CHEADER));
2289       /* XXX: Use correct size */
2290       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
2291       log_error(LOG_LEVEL_ERROR,
2292          "Couldn't parse request line received from %s: %s",
2293          csp->ip_addr_str, jb_err_to_string(err));
2294
2295       free_http_request(csp->http);
2296       return JB_ERR_PARSE;
2297    }
2298
2299    /* Parse the rest of the client's headers. */
2300    init_list(headers);
2301    for (;;)
2302    {
2303       p = get_header(csp->client_iob);
2304
2305       if (p == NULL)
2306       {
2307          /* There are no additional headers to read. */
2308          break;
2309       }
2310       enlist(headers, p);
2311       freez(p);
2312    }
2313
2314    if (JB_ERR_OK != get_destination_from_https_headers(headers, csp->http))
2315    {
2316       /*
2317        * Our attempts to get the request destination
2318        * elsewhere failed.
2319        */
2320       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2321          (const unsigned char *)CHEADER, strlen(CHEADER));
2322       return JB_ERR_PARSE;
2323    }
2324
2325 #ifndef FEATURE_EXTENDED_HOST_PATTERNS
2326    /* Split the domain we just got for pattern matching */
2327    init_domain_components(csp->http);
2328 #endif
2329
2330 #ifdef FEATURE_TOGGLE
2331    if ((csp->flags & CSP_FLAG_TOGGLED_ON) != 0)
2332 #endif
2333    {
2334       /* Determine the actions for this URL */
2335       get_url_actions(csp, csp->http);
2336    }
2337
2338    enlist(csp->https_headers, csp->http->cmd);
2339
2340    /* Append the previously read headers */
2341    err = list_append_list_unique(csp->https_headers, headers);
2342    destroy_list(headers);
2343    if (JB_ERR_OK != err)
2344    {
2345       /* XXX: Send error message */
2346       return err;
2347    }
2348
2349    /* XXX: Work around crash */
2350    csp->error_message = NULL;
2351
2352    /* XXX: Why do this here? */
2353    csp->http->ssl = 1;
2354
2355    err = sed_https(csp);
2356    if (JB_ERR_OK != err)
2357    {
2358       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2359          (const unsigned char *)CHEADER, strlen(CHEADER));
2360       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
2361          csp->ip_addr_str);
2362       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
2363          csp->ip_addr_str, csp->http->cmd);
2364       return JB_ERR_PARSE;
2365    }
2366
2367    log_error(LOG_LEVEL_HEADER, "Encrypted request processed");
2368    log_applied_actions(csp->action);
2369
2370    return err;
2371
2372 }
2373 #endif
2374
2375
2376 /*********************************************************************
2377  *
2378  * Function    :  handle_established_connection
2379  *
2380  * Description :  Shuffle data between client and server once the
2381  *                connection has been established.
2382  *
2383  * Parameters  :
2384  *          1  :  csp = Current client state (buffers, headers, etc...)
2385  *
2386  * Returns     :  Nothing.
2387  *
2388  *********************************************************************/
2389 static void handle_established_connection(struct client_state *csp)
2390 {
2391    char *hdr;
2392    char *p;
2393    int n;
2394 #ifdef HAVE_POLL
2395    struct pollfd poll_fds[2];
2396 #else
2397    fd_set rfds;
2398    jb_socket maxfd;
2399    struct timeval timeout;
2400 #endif
2401    int server_body;
2402    int ms_iis5_hack = 0;
2403    unsigned long long byte_count = 0;
2404    struct http_request *http;
2405    long len = 0; /* for buffer sizes (and negative error codes) */
2406    int buffer_and_filter_content = 0;
2407    unsigned int write_delay;
2408 #ifdef FEATURE_HTTPS_INSPECTION
2409    int ret = 0;
2410    int use_ssl_tunnel = 0;
2411    csp->dont_verify_certificate = 0;
2412
2413    /*
2414     * Preset flags informing if SSL connections with server or client
2415     * are opened or closed
2416     */
2417    csp->ssl_with_server_is_opened = 0;
2418    csp->ssl_with_client_is_opened = 0;
2419
2420    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION))
2421    {
2422       /* Pass encrypted content without filtering. */
2423       use_ssl_tunnel = 1;
2424    }
2425 #endif
2426
2427    /* Skeleton for HTTP response, if we should intercept the request */
2428    struct http_response *rsp;
2429 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2430    int watch_client_socket;
2431 #endif
2432
2433    csp->receive_buffer_size = csp->config->receive_buffer_size;
2434    csp->receive_buffer = zalloc(csp->receive_buffer_size + 1);
2435    if (csp->receive_buffer == NULL)
2436    {
2437       log_error(LOG_LEVEL_ERROR,
2438          "Out of memory. Failed to allocate the receive buffer.");
2439       rsp = cgi_error_memory();
2440       send_crunch_response(csp, rsp);
2441       return;
2442    }
2443
2444    http = csp->http;
2445
2446 #ifndef HAVE_POLL
2447    maxfd = (csp->cfd > csp->server_connection.sfd) ?
2448       csp->cfd : csp->server_connection.sfd;
2449 #endif
2450
2451    /* pass data between the client and server
2452     * until one or the other shuts down the connection.
2453     */
2454
2455    server_body = 0;
2456
2457 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2458    watch_client_socket = 0 == (csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING);
2459 #endif
2460    write_delay = get_write_delay(csp);
2461
2462    for (;;)
2463    {
2464 #ifndef HAVE_POLL
2465 #ifdef __OS2__
2466       /*
2467        * FD_ZERO here seems to point to an errant macro which crashes.
2468        * So do this by hand for now...
2469        */
2470       memset(&rfds,0x00,sizeof(fd_set));
2471 #else
2472       FD_ZERO(&rfds);
2473 #endif
2474 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2475       if (!watch_client_socket)
2476       {
2477          maxfd = csp->server_connection.sfd;
2478       }
2479       else
2480 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2481       {
2482          FD_SET(csp->cfd, &rfds);
2483       }
2484
2485       FD_SET(csp->server_connection.sfd, &rfds);
2486 #endif /* ndef HAVE_POLL */
2487
2488 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2489       if ((csp->flags & CSP_FLAG_CHUNKED)
2490          && !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
2491          && ((csp->iob->eod - csp->iob->cur) >= 5)
2492          && !memcmp(csp->iob->eod-5, "0\r\n\r\n", 5))
2493       {
2494          /*
2495           * XXX: This check should be obsolete now,
2496           *      but let's wait a while to be sure.
2497           */
2498          log_error(LOG_LEVEL_CONNECT,
2499             "Looks like we got the last chunk together with "
2500             "the server headers but didn't detect it earlier. "
2501             "We better stop reading.");
2502          byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
2503          csp->expected_content_length = byte_count;
2504          csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2505       }
2506       if (server_body && server_response_is_complete(csp, byte_count))
2507       {
2508          if (csp->expected_content_length == byte_count)
2509          {
2510             log_error(LOG_LEVEL_CONNECT,
2511                "Done reading from server. Content length: %llu as expected. "
2512                "Bytes most recently read: %d.",
2513                byte_count, len);
2514          }
2515          else
2516          {
2517             log_error(LOG_LEVEL_CONNECT,
2518                "Done reading from server. Expected content length: %llu. "
2519                "Actual content length: %llu. Bytes most recently read: %d.",
2520                csp->expected_content_length, byte_count, len);
2521          }
2522          len = 0;
2523          /*
2524           * XXX: Should not jump around, handle_established_connection()
2525           * is complicated enough already.
2526           */
2527          goto reading_done;
2528       }
2529 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
2530
2531 #ifdef FEATURE_HTTPS_INSPECTION
2532       /*
2533        * Test if some data from client or destination server are pending
2534        * on TLS/SSL. We must work with them preferably. TLS/SSL data can
2535        * be pending because of maximal fragment size.
2536        */
2537       int read_ssl_server = 0;
2538       int read_ssl_client = 0;
2539
2540       if (client_use_ssl(csp))
2541       {
2542          read_ssl_client = is_ssl_pending(&(csp->mbedtls_client_attr.ssl)) != 0;
2543       }
2544
2545       if (server_use_ssl(csp))
2546       {
2547          read_ssl_server = is_ssl_pending(&(csp->mbedtls_server_attr.ssl)) != 0;
2548       }
2549
2550       if (!read_ssl_server && !read_ssl_client)
2551 #endif
2552       {
2553 #ifdef HAVE_POLL
2554          poll_fds[0].fd = csp->cfd;
2555 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2556          if (!watch_client_socket)
2557          {
2558             /*
2559              * Ignore incoming data, but still watch out
2560              * for disconnects etc. These flags are always
2561              * implied anyway but explicitly setting them
2562              * doesn't hurt.
2563              */
2564             poll_fds[0].events = POLLERR|POLLHUP;
2565          }
2566          else
2567 #endif
2568          {
2569             poll_fds[0].events = POLLIN;
2570          }
2571          poll_fds[1].fd = csp->server_connection.sfd;
2572          poll_fds[1].events = POLLIN;
2573          n = poll(poll_fds, 2, csp->config->socket_timeout * 1000);
2574 #else
2575          timeout.tv_sec = csp->config->socket_timeout;
2576          timeout.tv_usec = 0;
2577          n = select((int)maxfd + 1, &rfds, NULL, NULL, &timeout);
2578 #endif /* def HAVE_POLL */
2579
2580          /*server or client not responding in timeout */
2581          if (n == 0)
2582          {
2583             log_error(LOG_LEVEL_CONNECT, "Socket timeout %d reached: %s",
2584                csp->config->socket_timeout, http->url);
2585             if ((byte_count == 0) && (http->ssl == 0))
2586             {
2587                send_crunch_response(csp, error_response(csp, "connection-timeout"));
2588             }
2589             mark_server_socket_tainted(csp);
2590 #ifdef FEATURE_HTTPS_INSPECTION
2591             close_client_and_server_ssl_connections(csp);
2592 #endif
2593             return;
2594          }
2595          else if (n < 0)
2596          {
2597 #ifdef HAVE_POLL
2598             log_error(LOG_LEVEL_ERROR, "poll() failed!: %E");
2599 #else
2600             log_error(LOG_LEVEL_ERROR, "select() failed!: %E");
2601 #endif
2602             mark_server_socket_tainted(csp);
2603 #ifdef FEATURE_HTTPS_INSPECTION
2604             close_client_and_server_ssl_connections(csp);
2605 #endif
2606             return;
2607          }
2608       }
2609 #ifdef FEATURE_HTTPS_INSPECTION
2610       else
2611       {
2612          /* set FD if some data are pending on TLS/SSL connections */
2613 #ifndef HAVE_POLL
2614          FD_ZERO(&rfds);
2615 #endif
2616          if (read_ssl_client)
2617          {
2618 #ifdef HAVE_POLL
2619             poll_fds[0].fd = csp->cfd;
2620             poll_fds[0].events = POLLIN;
2621 #else
2622             FD_SET(csp->cfd, &rfds);
2623 #endif
2624             n++;
2625          }
2626
2627          if (read_ssl_server)
2628          {
2629 #ifdef HAVE_POLL
2630             poll_fds[1].fd = csp->server_connection.sfd;
2631             poll_fds[1].events = POLLIN;
2632 #else
2633             FD_SET(csp->server_connection.sfd, &rfds);
2634 #endif
2635             n++;
2636          }
2637       }
2638 #endif
2639       /*
2640        * This is the body of the browser's request,
2641        * just read and write it.
2642        *
2643        * Receives data from browser and sends it to server
2644        *
2645        * XXX: Make sure the client doesn't use pipelining
2646        * behind Privoxy's back.
2647        */
2648 #ifdef HAVE_POLL
2649       if ((poll_fds[0].revents & (POLLERR|POLLHUP|POLLNVAL)) != 0)
2650       {
2651          log_error(LOG_LEVEL_CONNECT,
2652             "The client socket %d has become unusable while "
2653             "the server socket %d is still open.",
2654             csp->cfd, csp->server_connection.sfd);
2655          mark_server_socket_tainted(csp);
2656          break;
2657       }
2658
2659       if (poll_fds[0].revents != 0)
2660 #else
2661       if (FD_ISSET(csp->cfd, &rfds))
2662 #endif /* def HAVE_POLL*/
2663       {
2664          int max_bytes_to_read = (int)csp->receive_buffer_size;
2665
2666 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2667          if ((csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ))
2668          {
2669             if (data_is_available(csp->cfd, 0))
2670             {
2671                /*
2672                 * If the next request is already waiting, we have
2673                 * to stop select()ing the client socket. Otherwise
2674                 * we would always return right away and get nothing
2675                 * else done.
2676                 */
2677                watch_client_socket = 0;
2678                log_error(LOG_LEVEL_CONNECT,
2679                   "Stop watching client socket %d. "
2680                   "There's already another request waiting.",
2681                   csp->cfd);
2682                continue;
2683             }
2684             /*
2685              * If the client socket is set, but there's no data
2686              * available on the socket, the client went fishing
2687              * and continuing talking to the server makes no sense.
2688              */
2689             log_error(LOG_LEVEL_CONNECT,
2690                "The client closed socket %d while "
2691                "the server socket %d is still open.",
2692                csp->cfd, csp->server_connection.sfd);
2693             mark_server_socket_tainted(csp);
2694             break;
2695          }
2696          if (csp->expected_client_content_length != 0)
2697          {
2698             if (csp->expected_client_content_length < csp->receive_buffer_size)
2699             {
2700                max_bytes_to_read = (int)csp->expected_client_content_length;
2701             }
2702             log_error(LOG_LEVEL_CONNECT,
2703                "Waiting for up to %d bytes from the client.",
2704                max_bytes_to_read);
2705          }
2706          assert(max_bytes_to_read <= csp->receive_buffer_size);
2707 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2708
2709 #ifdef FEATURE_HTTPS_INSPECTION
2710          /*
2711           * Reading data from standard or secured connection (HTTP/HTTPS)
2712           */
2713          if (client_use_ssl(csp))
2714          {
2715             /*
2716              * Receiving HTTP request from client over TLS/SSL and sending
2717              * it to server over TLS/SSL.
2718              */
2719             len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl),
2720                (unsigned char *)csp->receive_buffer, (size_t)max_bytes_to_read);
2721
2722             if (len <= 0)
2723             {
2724                mark_server_socket_tainted(csp);
2725                break;
2726             }
2727
2728             ret = ssl_send_data(&(csp->mbedtls_server_attr.ssl),
2729                (const unsigned char *)csp->receive_buffer, (size_t)len);
2730
2731             if (ret < 0)
2732             {
2733                log_error(LOG_LEVEL_ERROR,
2734                   "Send request over TLS/SSL to: %s failed", http->host);
2735                mark_server_socket_tainted(csp);
2736                close_client_and_server_ssl_connections(csp);
2737                return;
2738             }
2739          }
2740          else
2741 #endif /* def FEATURE_HTTPS_INSPECTION */
2742          {
2743             len = read_socket(csp->cfd, csp->receive_buffer, max_bytes_to_read);
2744
2745             if (len <= 0)
2746             {
2747                /* XXX: not sure if this is necessary. */
2748                mark_server_socket_tainted(csp);
2749                break; /* "game over, man" */
2750             }
2751
2752 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2753             if (csp->expected_client_content_length != 0)
2754             {
2755                assert(len <= max_bytes_to_read);
2756                csp->expected_client_content_length -= (unsigned)len;
2757                log_error(LOG_LEVEL_CONNECT,
2758                   "Expected client content length set to %llu "
2759                   "after reading %d bytes.",
2760                   csp->expected_client_content_length, len);
2761                if (csp->expected_client_content_length == 0)
2762                {
2763                   log_error(LOG_LEVEL_CONNECT,
2764                      "Done reading from the client.");
2765                   csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
2766                }
2767             }
2768 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2769
2770             if (write_socket(csp->server_connection.sfd, csp->receive_buffer, (size_t)len))
2771             {
2772                log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host);
2773                mark_server_socket_tainted(csp);
2774 #ifdef FEATURE_HTTPS_INSPECTION
2775                close_client_and_server_ssl_connections(csp);
2776 #endif
2777                return;
2778             }
2779          }
2780          continue;
2781       }
2782
2783       /*
2784        * The server wants to talk. It could be the header or the body.
2785        * If `hdr' is null, then it's the header otherwise it's the body.
2786        * FIXME: Does `hdr' really mean `host'? No.
2787        */
2788 #ifdef HAVE_POLL
2789       if (poll_fds[1].revents != 0)
2790 #else
2791       if (FD_ISSET(csp->server_connection.sfd, &rfds))
2792 #endif /* HAVE_POLL */
2793       {
2794 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2795          /*
2796           * If we are buffering content, we don't want to eat up to
2797           * buffer-limit bytes if the client no longer cares about them.
2798           * If we aren't buffering, however, a dead client socket will be
2799           * noticed pretty much right away anyway, so we can reduce the
2800           * overhead by skipping the check.
2801           */
2802          if (buffer_and_filter_content && !socket_is_still_alive(csp->cfd))
2803          {
2804 #ifdef _WIN32
2805             log_error(LOG_LEVEL_CONNECT,
2806                "The server still wants to talk, but the client may already have hung up on us.");
2807 #else
2808             log_error(LOG_LEVEL_CONNECT,
2809                "The server still wants to talk, but the client hung up on us.");
2810             mark_server_socket_tainted(csp);
2811 #ifdef FEATURE_HTTPS_INSPECTION
2812             close_client_and_server_ssl_connections(csp);
2813 #endif
2814             return;
2815 #endif /* def _WIN32 */
2816          }
2817 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2818
2819 #ifdef FEATURE_HTTPS_INSPECTION
2820          /*
2821           * Reading data from standard or secured connection (HTTP/HTTPS)
2822           */
2823          if (server_use_ssl(csp))
2824          {
2825             len = ssl_recv_data(&(csp->mbedtls_server_attr.ssl),
2826                (unsigned char *)csp->receive_buffer, csp->receive_buffer_size);
2827          }
2828          else
2829 #endif
2830          {
2831             len = read_socket(csp->server_connection.sfd, csp->receive_buffer,
2832                (int)csp->receive_buffer_size);
2833          }
2834
2835          if (len < 0)
2836          {
2837             log_error(LOG_LEVEL_ERROR, "read from: %s failed: %E", http->host);
2838
2839             if ((http->ssl && (csp->fwd == NULL))
2840 #ifdef FEATURE_HTTPS_INSPECTION
2841                && use_ssl_tunnel
2842 #endif
2843                 )
2844             {
2845                /*
2846                 * Just hang up. We already confirmed the client's CONNECT
2847                 * request with status code 200 and unencrypted content is
2848                 * no longer welcome.
2849                 */
2850                log_error(LOG_LEVEL_ERROR,
2851                   "CONNECT already confirmed. Unable to tell the client about the problem.");
2852                return;
2853             }
2854             else if (byte_count)
2855             {
2856                /*
2857                 * Just hang up. We already transmitted the original headers
2858                 * and parts of the original content and therefore missed the
2859                 * chance to send an error message (without risking data corruption).
2860                 *
2861                 * XXX: we could retry with a fancy range request here.
2862                 */
2863                log_error(LOG_LEVEL_ERROR, "Already forwarded the original headers. "
2864                   "Unable to tell the client about the problem.");
2865                mark_server_socket_tainted(csp);
2866 #ifdef FEATURE_HTTPS_INSPECTION
2867                close_client_and_server_ssl_connections(csp);
2868 #endif
2869                return;
2870             }
2871             /*
2872              * XXX: Consider handling the cases above the same.
2873              */
2874             mark_server_socket_tainted(csp);
2875             len = 0;
2876          }
2877
2878 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2879          if (csp->flags & CSP_FLAG_CHUNKED)
2880          {
2881             if ((len >= 5) && !memcmp(csp->receive_buffer+len-5, "0\r\n\r\n", 5))
2882             {
2883                /* XXX: this is a temporary hack */
2884                log_error(LOG_LEVEL_CONNECT,
2885                   "Looks like we reached the end of the last chunk. "
2886                   "We better stop reading.");
2887                csp->expected_content_length = byte_count + (unsigned long long)len;
2888                csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2889             }
2890          }
2891          reading_done:
2892 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
2893
2894          /*
2895           * This is guaranteed by allocating with zalloc_or_die()
2896           * and never (intentionally) writing to the last byte.
2897           *
2898           * csp->receive_buffer_size is the size of the part of the
2899           * buffer we intentionally write to, but we actually
2900           * allocated csp->receive_buffer_size+1 bytes so the assertion
2901           * stays within the allocated range.
2902           */
2903          assert(csp->receive_buffer[csp->receive_buffer_size] == '\0');
2904
2905          /*
2906           * Add a trailing zero to let be able to use string operations.
2907           * XXX: do we still need this with filter_popups gone?
2908           */
2909          assert(len <= csp->receive_buffer_size);
2910          csp->receive_buffer[len] = '\0';
2911
2912          /*
2913           * Normally, this would indicate that we've read
2914           * as much as the server has sent us and we can
2915           * close the client connection.  However, Microsoft
2916           * in its wisdom has released IIS/5 with a bug that
2917           * prevents it from sending the trailing \r\n in
2918           * a 302 redirect header (and possibly other headers).
2919           * To work around this if we've haven't parsed
2920           * a full header we'll append a trailing \r\n
2921           * and see if this now generates a valid one.
2922           *
2923           * This hack shouldn't have any impacts.  If we've
2924           * already transmitted the header or if this is a
2925           * SSL connection, then we won't bother with this
2926           * hack.  So we only work on partially received
2927           * headers.  If we append a \r\n and this still
2928           * doesn't generate a valid header, then we won't
2929           * transmit anything to the client.
2930           */
2931          if (len == 0)
2932          {
2933
2934             if (server_body || (http->ssl
2935 #ifdef FEATURE_HTTPS_INSPECTION
2936                   && use_ssl_tunnel
2937 #endif
2938                ))
2939             {
2940                /*
2941                 * If we have been buffering up the document,
2942                 * now is the time to apply content modification
2943                 * and send the result to the client.
2944                 */
2945                if (buffer_and_filter_content)
2946                {
2947                   p = execute_content_filters(csp);
2948                   /*
2949                    * If content filtering fails, use the original
2950                    * buffer and length.
2951                    * (see p != NULL ? p : csp->iob->cur below)
2952                    */
2953                   if (NULL == p)
2954                   {
2955                      csp->content_length = (size_t)(csp->iob->eod - csp->iob->cur);
2956                   }
2957 #ifdef FEATURE_COMPRESSION
2958                   else if ((csp->flags & CSP_FLAG_CLIENT_SUPPORTS_DEFLATE)
2959                      && (csp->content_length > LOWER_LENGTH_LIMIT_FOR_COMPRESSION))
2960                   {
2961                      char *compressed_content = compress_buffer(p,
2962                         (size_t *)&csp->content_length, csp->config->compression_level);
2963                      if (compressed_content != NULL)
2964                      {
2965                         freez(p);
2966                         p = compressed_content;
2967                         csp->flags |= CSP_FLAG_BUFFERED_CONTENT_DEFLATED;
2968                      }
2969                   }
2970 #endif
2971
2972                   if (JB_ERR_OK != update_server_headers(csp))
2973                   {
2974                      log_error(LOG_LEVEL_FATAL,
2975                         "Failed to update server headers. after filtering.");
2976                   }
2977
2978                   hdr = list_to_text(csp->headers);
2979                   if (hdr == NULL)
2980                   {
2981                      /* FIXME Should handle error properly */
2982                      log_error(LOG_LEVEL_FATAL, "Out of memory parsing server header");
2983                   }
2984
2985 #ifdef FEATURE_HTTPS_INSPECTION
2986                   /*
2987                    * Sending data with standard or secured connection (HTTP/HTTPS)
2988                    */
2989                   if (client_use_ssl(csp))
2990                   {
2991                      if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2992                             (const unsigned char *)hdr, strlen(hdr)) < 0)
2993                         || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2994                               (const unsigned char *) ((p != NULL) ? p : csp->iob->cur),
2995                               csp->content_length) < 0))
2996                      {
2997                         log_error(LOG_LEVEL_ERROR, "write modified content to "
2998                            "client over TLS/SSL failed");
2999                         freez(hdr);
3000                         freez(p);
3001                         mark_server_socket_tainted(csp);
3002                         close_client_and_server_ssl_connections(csp);
3003                         return;
3004                      }
3005                   }
3006                   else
3007 #endif /* def FEATURE_HTTPS_INSPECTION */
3008                   {
3009                      if (write_socket_delayed(csp->cfd, hdr, strlen(hdr), write_delay)
3010                       || write_socket_delayed(csp->cfd, ((p != NULL) ? p : csp->iob->cur),
3011                          (size_t)csp->content_length, write_delay))
3012                      {
3013                         log_error(LOG_LEVEL_ERROR, "write modified content to client failed: %E");
3014                         freez(hdr);
3015                         freez(p);
3016                         mark_server_socket_tainted(csp);
3017 #ifdef FEATURE_HTTPS_INSPECTION
3018                         close_client_and_server_ssl_connections(csp);
3019 #endif
3020                         return;
3021                      }
3022                   }
3023
3024                   freez(hdr);
3025                   freez(p);
3026                }
3027
3028                break; /* "game over, man" */
3029             }
3030
3031             /*
3032              * This is NOT the body, so
3033              * Let's pretend the server just sent us a blank line.
3034              */
3035             snprintf(csp->receive_buffer, csp->receive_buffer_size, "\r\n");
3036             len = (int)strlen(csp->receive_buffer);
3037
3038             /*
3039              * Now, let the normal header parsing algorithm below do its
3040              * job.  If it fails, we'll exit instead of continuing.
3041              */
3042
3043             ms_iis5_hack = 1;
3044          }
3045
3046          /*
3047           * If we're in the body of the server document, just write it to
3048           * the client, unless we need to buffer the body for later
3049           * content-filtering.
3050           */
3051          if (server_body || (http->ssl
3052 #ifdef FEATURE_HTTPS_INSPECTION
3053                && use_ssl_tunnel
3054 #endif
3055             ))
3056          {
3057             if (buffer_and_filter_content)
3058             {
3059                /*
3060                 * If there is no memory left for buffering the content, or the buffer limit
3061                 * has been reached, switch to non-filtering mode, i.e. make & write the
3062                 * header, flush the iob and buf, and get out of the way.
3063                 */
3064                if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3065                {
3066                   size_t hdrlen;
3067                   long flushed;
3068
3069                   log_error(LOG_LEVEL_INFO,
3070                      "Flushing header and buffers. Stepping back from filtering.");
3071
3072                   hdr = list_to_text(csp->headers);
3073                   if (hdr == NULL)
3074                   {
3075                      /*
3076                       * Memory is too tight to even generate the header.
3077                       * Send our static "Out-of-memory" page.
3078                       */
3079                      log_error(LOG_LEVEL_ERROR, "Out of memory while trying to flush.");
3080                      rsp = cgi_error_memory();
3081                      send_crunch_response(csp, rsp);
3082                      mark_server_socket_tainted(csp);
3083 #ifdef FEATURE_HTTPS_INSPECTION
3084                      close_client_and_server_ssl_connections(csp);
3085 #endif
3086                      return;
3087                   }
3088                   hdrlen = strlen(hdr);
3089
3090 #ifdef FEATURE_HTTPS_INSPECTION
3091                   /*
3092                    * Sending data with standard or secured connection (HTTP/HTTPS)
3093                    */
3094                   if (client_use_ssl(csp))
3095                   {
3096                      if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3097                             (const unsigned char *)hdr, hdrlen) < 0)
3098                         || ((flushed = ssl_flush_socket(&(csp->mbedtls_client_attr.ssl),
3099                                 csp->iob)) < 0)
3100                         || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3101                               (const unsigned char *)csp->receive_buffer, (size_t)len) < 0))
3102                      {
3103                         log_error(LOG_LEVEL_CONNECT,
3104                            "Flush header and buffers to client failed");
3105                         freez(hdr);
3106                         mark_server_socket_tainted(csp);
3107                         close_client_and_server_ssl_connections(csp);
3108                         return;
3109                      }
3110                   }
3111                   else
3112 #endif /* def FEATURE_HTTPS_INSPECTION */
3113                   {
3114                      if (write_socket_delayed(csp->cfd, hdr, hdrlen, write_delay)
3115                       || ((flushed = flush_iob(csp->cfd, csp->iob, write_delay)) < 0)
3116                       || write_socket_delayed(csp->cfd, csp->receive_buffer, (size_t)len,
3117                             write_delay))
3118                      {
3119                         log_error(LOG_LEVEL_CONNECT,
3120                            "Flush header and buffers to client failed: %E");
3121                         freez(hdr);
3122                         mark_server_socket_tainted(csp);
3123 #ifdef FEATURE_HTTPS_INSPECTION
3124                         close_client_and_server_ssl_connections(csp);
3125 #endif
3126                         return;
3127                      }
3128                   }
3129
3130                   /*
3131                    * Reset the byte_count to the amount of bytes
3132                    * we just flushed. len will be added a few lines below,
3133                    * hdrlen doesn't matter for LOG_LEVEL_CLF.
3134                    */
3135                   byte_count = (unsigned long long)flushed;
3136                   freez(hdr);
3137                   buffer_and_filter_content = 0;
3138                   server_body = 1;
3139                }
3140             }
3141             else
3142             {
3143 #ifdef FEATURE_HTTPS_INSPECTION
3144                /*
3145                 * Sending data with standard or secured connection (HTTP/HTTPS)
3146                 */
3147                if (client_use_ssl(csp))
3148                {
3149                   ret = ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3150                      (const unsigned char *)csp->receive_buffer, (size_t)len);
3151                   if (ret < 0)
3152                   {
3153                      log_error(LOG_LEVEL_ERROR,
3154                         "Sending data to client failed");
3155                      mark_server_socket_tainted(csp);
3156                      close_client_and_server_ssl_connections(csp);
3157                      return;
3158                   }
3159                }
3160                else
3161 #endif /* def FEATURE_HTTPS_INSPECTION */
3162                {
3163                   if (write_socket_delayed(csp->cfd, csp->receive_buffer,
3164                         (size_t)len, write_delay))
3165                   {
3166                      log_error(LOG_LEVEL_ERROR, "write to client failed: %E");
3167                      mark_server_socket_tainted(csp);
3168 #ifdef FEATURE_HTTPS_INSPECTION
3169                      close_client_and_server_ssl_connections(csp);
3170 #endif
3171                      return;
3172                   }
3173                }
3174             }
3175             byte_count += (unsigned long long)len;
3176             continue;
3177          }
3178          else
3179          {
3180             /*
3181              * We're still looking for the end of the server's header.
3182              * Buffer up the data we just read.  If that fails, there's
3183              * little we can do but send our static out-of-memory page.
3184              */
3185             if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3186             {
3187                log_error(LOG_LEVEL_ERROR, "Out of memory while looking for end of server headers.");
3188                rsp = cgi_error_memory();
3189                send_crunch_response(csp, rsp);
3190                mark_server_socket_tainted(csp);
3191 #ifdef FEATURE_HTTPS_INSPECTION
3192                close_client_and_server_ssl_connections(csp);
3193 #endif
3194                return;
3195             }
3196
3197             /* Convert iob into something sed() can digest */
3198             if (JB_ERR_PARSE == get_server_headers(csp))
3199             {
3200                if (ms_iis5_hack)
3201                {
3202                   /*
3203                    * Well, we tried our MS IIS/5 hack and it didn't work.
3204                    * The header is incomplete and there isn't anything
3205                    * we can do about it.
3206                    */
3207                   log_error(LOG_LEVEL_ERROR, "Invalid server headers. "
3208                      "Applying the MS IIS5 hack didn't help.");
3209                   log_error(LOG_LEVEL_CLF,
3210                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3211 #ifdef FEATURE_HTTPS_INSPECTION
3212                   /*
3213                    * Sending data with standard or secured connection (HTTP/HTTPS)
3214                    */
3215                   if (client_use_ssl(csp))
3216                   {
3217                      ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3218                         (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3219                         strlen(INVALID_SERVER_HEADERS_RESPONSE));
3220                   }
3221                   else
3222 #endif /* def FEATURE_HTTPS_INSPECTION */
3223                   {
3224                      write_socket_delayed(csp->cfd,
3225                         INVALID_SERVER_HEADERS_RESPONSE,
3226                         strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3227                   }
3228                   mark_server_socket_tainted(csp);
3229 #ifdef FEATURE_HTTPS_INSPECTION
3230                   close_client_and_server_ssl_connections(csp);
3231 #endif
3232                   return;
3233                }
3234                else
3235                {
3236                   /*
3237                    * Since we have to wait for more from the server before
3238                    * we can parse the headers we just continue here.
3239                    */
3240                   log_error(LOG_LEVEL_CONNECT,
3241                      "Continuing buffering server headers from socket %d. "
3242                      "Bytes most recently read: %d.", csp->cfd, len);
3243                   continue;
3244                }
3245             }
3246             else
3247             {
3248                /*
3249                 * Account for the content bytes we
3250                 * might have gotten with the headers.
3251                 */
3252                assert(csp->iob->eod >= csp->iob->cur);
3253                byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
3254             }
3255
3256             /* Did we actually get anything? */
3257             if (NULL == csp->headers->first)
3258             {
3259                if ((csp->flags & CSP_FLAG_REUSED_CLIENT_CONNECTION))
3260                {
3261                   log_error(LOG_LEVEL_ERROR,
3262                      "No server or forwarder response received on socket %d. "
3263                      "Closing client socket %d without sending data.",
3264                      csp->server_connection.sfd, csp->cfd);
3265                   log_error(LOG_LEVEL_CLF,
3266                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3267                }
3268                else
3269                {
3270                   log_error(LOG_LEVEL_ERROR,
3271                      "No server or forwarder response received on socket %d.",
3272                      csp->server_connection.sfd);
3273                   send_crunch_response(csp, error_response(csp, "no-server-data"));
3274                }
3275                free_http_request(http);
3276                mark_server_socket_tainted(csp);
3277 #ifdef FEATURE_HTTPS_INSPECTION
3278                close_client_and_server_ssl_connections(csp);
3279 #endif
3280                return;
3281             }
3282
3283             if (!csp->headers->first->str)
3284             {
3285                log_error(LOG_LEVEL_ERROR, "header search: csp->headers->first->str == NULL, assert will be called");
3286             }
3287             assert(csp->headers->first->str);
3288
3289             if (strncmpic(csp->headers->first->str, "HTTP", 4) &&
3290                 strncmpic(csp->headers->first->str, "ICY", 3))
3291             {
3292                /*
3293                 * It doesn't look like a HTTP (or Shoutcast) response:
3294                 * tell the client and log the problem.
3295                 */
3296                if (strlen(csp->headers->first->str) > 30)
3297                {
3298                   csp->headers->first->str[30] = '\0';
3299                }
3300                log_error(LOG_LEVEL_ERROR,
3301                   "Invalid server or forwarder response. Starts with: %s",
3302                   csp->headers->first->str);
3303                log_error(LOG_LEVEL_CLF,
3304                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3305 #ifdef FEATURE_HTTPS_INSPECTION
3306                /*
3307                 * Sending data with standard or secured connection (HTTP/HTTPS)
3308                 */
3309                if (client_use_ssl(csp))
3310                {
3311                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3312                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3313                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3314                }
3315                else
3316 #endif /* def FEATURE_HTTPS_INSPECTION */
3317                {
3318                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3319                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3320                }
3321                free_http_request(http);
3322                mark_server_socket_tainted(csp);
3323 #ifdef FEATURE_HTTPS_INSPECTION
3324                close_client_and_server_ssl_connections(csp);
3325 #endif
3326                return;
3327             }
3328
3329             /*
3330              * We have now received the entire server header,
3331              * filter it and send the result to the client
3332              */
3333             if (JB_ERR_OK != sed(csp, FILTER_SERVER_HEADERS))
3334             {
3335                log_error(LOG_LEVEL_CLF,
3336                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3337 #ifdef FEATURE_HTTPS_INSPECTION
3338                /*
3339                 * Sending data with standard or secured connection (HTTP/HTTPS)
3340                 */
3341                if (client_use_ssl(csp))
3342                {
3343                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3344                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3345                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3346                }
3347                else
3348 #endif
3349                {
3350                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3351                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3352                }
3353                free_http_request(http);
3354                mark_server_socket_tainted(csp);
3355 #ifdef FEATURE_HTTPS_INSPECTION
3356                close_client_and_server_ssl_connections(csp);
3357 #endif
3358                return;
3359             }
3360             hdr = list_to_text(csp->headers);
3361             if (hdr == NULL)
3362             {
3363                /* FIXME Should handle error properly */
3364                log_error(LOG_LEVEL_FATAL, "Out of memory parsing server header");
3365             }
3366
3367             if ((csp->flags & CSP_FLAG_CHUNKED)
3368                && !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
3369                && ((csp->iob->eod - csp->iob->cur) >= 5)
3370                && !memcmp(csp->iob->eod-5, "0\r\n\r\n", 5))
3371             {
3372                log_error(LOG_LEVEL_CONNECT,
3373                   "Looks like we got the last chunk together with "
3374                   "the server headers. We better stop reading.");
3375                byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
3376                csp->expected_content_length = byte_count;
3377                csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
3378             }
3379
3380             csp->server_connection.response_received = time(NULL);
3381
3382             if (crunch_response_triggered(csp, crunchers_light))
3383             {
3384                /*
3385                 * One of the tags created by a server-header
3386                 * tagger triggered a crunch. We already
3387                 * delivered the crunch response to the client
3388                 * and are done here after cleaning up.
3389                 */
3390                freez(hdr);
3391                mark_server_socket_tainted(csp);
3392 #ifdef FEATURE_HTTPS_INSPECTION
3393                close_client_and_server_ssl_connections(csp);
3394 #endif
3395                return;
3396             }
3397
3398             /* Buffer and pcrs filter this if appropriate. */
3399             buffer_and_filter_content = content_requires_filtering(csp);
3400
3401             if (!buffer_and_filter_content)
3402             {
3403                /*
3404                 * Write the server's (modified) header to
3405                 * the client (along with anything else that
3406                 * may be in the buffer). Use standard or secured
3407                 * connection.
3408                 */
3409 #ifdef FEATURE_HTTPS_INSPECTION
3410                if (client_use_ssl(csp))
3411                {
3412                   if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3413                           (const unsigned char *)hdr, strlen(hdr)) < 0)
3414                      || (len = ssl_flush_socket(&(csp->mbedtls_client_attr.ssl),
3415                             csp->iob) < 0))
3416                   {
3417                      log_error(LOG_LEVEL_CONNECT, "Write header to client failed");
3418
3419                      /*
3420                       * The write failed, so don't bother mentioning it
3421                       * to the client... it probably can't hear us anyway.
3422                       */
3423                      freez(hdr);
3424                      mark_server_socket_tainted(csp);
3425 #ifdef FEATURE_HTTPS_INSPECTION
3426                      close_client_and_server_ssl_connections(csp);
3427 #endif
3428                      return;
3429                   }
3430                }
3431                else
3432 #endif /* def FEATURE_HTTPS_INSPECTION */
3433                {
3434                   if (write_socket_delayed(csp->cfd, hdr, strlen(hdr), write_delay)
3435                      || ((len = flush_iob(csp->cfd, csp->iob, write_delay)) < 0))
3436                   {
3437                      log_error(LOG_LEVEL_ERROR,
3438                         "write header to client failed");
3439                      /*
3440                       * The write failed, so don't bother mentioning it
3441                       * to the client... it probably can't hear us anyway.
3442                       */
3443                      freez(hdr);
3444                      mark_server_socket_tainted(csp);
3445 #ifdef FEATURE_HTTPS_INSPECTION
3446                      close_client_and_server_ssl_connections(csp);
3447 #endif
3448                      return;
3449                   }
3450                }
3451                                 }
3452
3453             /* we're finished with the server's header */
3454
3455             freez(hdr);
3456             server_body = 1;
3457
3458             /*
3459              * If this was a MS IIS/5 hack then it means the server
3460              * has already closed the connection. Nothing more to read.
3461              * Time to bail.
3462              */
3463             if (ms_iis5_hack)
3464             {
3465                log_error(LOG_LEVEL_ERROR,
3466                   "Closed server connection detected. "
3467                   "Applying the MS IIS5 hack didn't help.");
3468                log_error(LOG_LEVEL_CLF,
3469                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3470 #ifdef FEATURE_HTTPS_INSPECTION
3471                /*
3472                 * Sending data with standard or secured connection (HTTP/HTTPS)
3473                 */
3474                if (client_use_ssl(csp))
3475                {
3476                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3477                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3478                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3479                }
3480                else
3481 #endif /* def FEATURE_HTTPS_INSPECTION */
3482                {
3483                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3484                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3485                }
3486                mark_server_socket_tainted(csp);
3487 #ifdef FEATURE_HTTPS_INSPECTION
3488                close_client_and_server_ssl_connections(csp);
3489 #endif
3490                return;
3491             }
3492          }
3493          continue;
3494       }
3495       mark_server_socket_tainted(csp);
3496 #ifdef FEATURE_HTTPS_INSPECTION
3497       close_client_and_server_ssl_connections(csp);
3498 #endif
3499       return; /* huh? we should never get here */
3500    }
3501 #ifdef FEATURE_HTTPS_INSPECTION
3502    close_client_and_server_ssl_connections(csp);
3503 #endif
3504    if (csp->content_length == 0)
3505    {
3506       /*
3507        * If Privoxy didn't recalculate the Content-Length,
3508        * byte_count is still correct.
3509        */
3510       csp->content_length = byte_count;
3511    }
3512
3513 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3514    if ((csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
3515       && (csp->expected_content_length != byte_count))
3516    {
3517       log_error(LOG_LEVEL_CONNECT,
3518          "Received %llu bytes while expecting %llu.",
3519          byte_count, csp->expected_content_length);
3520       mark_server_socket_tainted(csp);
3521    }
3522 #endif
3523
3524    log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 %llu",
3525       csp->ip_addr_str, http->ocmd, csp->content_length);
3526
3527    csp->server_connection.timestamp = time(NULL);
3528 }
3529
3530
3531 /*********************************************************************
3532  *
3533  * Function    :  chat
3534  *
3535  * Description :  Once a connection from the client has been accepted,
3536  *                this function is called (via serve()) to handle the
3537  *                main business of the communication.  This function
3538  *                returns after dealing with a single request. It can
3539  *                be called multiple times with the same client socket
3540  *                if the client is keeping the connection alive.
3541  *
3542  *                The decision whether or not a client connection will
3543  *                be kept alive is up to the caller which also must
3544  *                close the client socket when done.
3545  *
3546  *                FIXME: chat is nearly thousand lines long.
3547  *                Ridiculous.
3548  *
3549  * Parameters  :
3550  *          1  :  csp = Current client state (buffers, headers, etc...)
3551  *
3552  * Returns     :  Nothing.
3553  *
3554  *********************************************************************/
3555 static void chat(struct client_state *csp)
3556 {
3557    const struct forward_spec *fwd;
3558    struct http_request *http;
3559    /* Skeleton for HTTP response, if we should intercept the request */
3560    struct http_response *rsp;
3561 #ifdef FEATURE_HTTPS_INSPECTION
3562    int use_ssl_tunnel = 0;
3563 #endif
3564
3565    http = csp->http;
3566
3567    if (receive_client_request(csp) != JB_ERR_OK)
3568    {
3569       return;
3570    }
3571    if (parse_client_request(csp) != JB_ERR_OK)
3572    {
3573       return;
3574    }
3575
3576    /* decide how to route the HTTP request */
3577    fwd = forward_url(csp, http);
3578    if (NULL == fwd)
3579    {
3580       log_error(LOG_LEVEL_FATAL, "gateway spec is NULL!?!?  This can't happen!");
3581       /* Never get here - LOG_LEVEL_FATAL causes program exit */
3582       return;
3583    }
3584
3585 #ifdef FEATURE_HTTPS_INSPECTION
3586    /*
3587     * Setting flags to use old solution with SSL tunnel and to disable
3588     * certificates verification.
3589     */
3590    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION))
3591    {
3592       use_ssl_tunnel = 1;
3593    }
3594
3595    if (http->ssl && csp->action->flags & ACTION_IGNORE_CERTIFICATE_ERRORS)
3596    {
3597       csp->dont_verify_certificate = 1;
3598    }
3599 #endif
3600
3601    /*
3602     * build the http request to send to the server
3603     * we have to do one of the following:
3604     *
3605     * create =    use the original HTTP request to create a new
3606     *             HTTP request that has either the path component
3607     *             without the http://domainspec (w/path) or the
3608     *             full orininal URL (w/url)
3609     *             Note that the path and/or the HTTP version may
3610     *             have been altered by now.
3611     *
3612     * SSL proxy = Open a socket to the host:port of the server
3613     *             and create TLS/SSL connection with server and
3614     *             with client. Then behave like mediator between
3615     *             client and server over TLS/SSL.
3616     *
3617     * SSL proxy = Pass the request unchanged if forwarding a CONNECT
3618     *    with     request to a parent proxy. Note that we'll be sending
3619     * forwarding  the CFAIL message ourselves if connecting to the parent
3620     *             fails, but we won't send a CSUCCEED message if it works,
3621     *             since that would result in a double message (ours and the
3622     *             parent's). After sending the request to the parent, we
3623     *             must parse answer and send it to client. If connection
3624     *             with server is established, we do TLS/SSL proxy. Otherwise
3625     *             we send parent response to client and close connections.
3626     *
3627     * here's the matrix:
3628     *                        SSL
3629     *                    0        1
3630     *                +--------+--------+
3631     *                |        |        |
3632     *             0  | create |   SSL  |
3633     *                | w/path |  proxy |
3634     *  Forwarding    +--------+--------+
3635     *                |        |   SSL  |
3636     *             1  | create |  proxy |
3637     *                | w/url  |+forward|
3638     *                +--------+--------+
3639     *
3640     */
3641
3642 #ifdef FEATURE_HTTPS_INSPECTION
3643    /*
3644     * Presetting SSL client and server flags
3645     */
3646    if (http->ssl && !use_ssl_tunnel)
3647    {
3648       http->client_ssl = 1;
3649       http->server_ssl = 1;
3650    }
3651    else
3652    {
3653       http->client_ssl = 0;
3654       http->server_ssl = 0;
3655    }
3656 #endif
3657
3658    if (http->ssl && connect_port_is_forbidden(csp))
3659    {
3660       const char *acceptable_connect_ports =
3661          csp->action->string[ACTION_STRING_LIMIT_CONNECT];
3662       assert(NULL != acceptable_connect_ports);
3663       log_error(LOG_LEVEL_INFO, "Request from %s marked for blocking. "
3664          "limit-connect{%s} doesn't allow CONNECT requests to %s",
3665          csp->ip_addr_str, acceptable_connect_ports, csp->http->hostport);
3666       csp->action->flags |= ACTION_BLOCK;
3667       http->ssl = 0;
3668 #ifdef FEATURE_HTTPS_INSPECTION
3669       http->client_ssl = 0;
3670       http->server_ssl = 0;
3671 #endif
3672    }
3673
3674
3675    freez(csp->headers->first->str);
3676    build_request_line(csp, fwd, &csp->headers->first->str);
3677
3678    /*
3679     * We have a request. Check if one of the crunchers wants it
3680     * unless the client wants to use TLS/SSL in which case we
3681     * haven't setup the TLS context yet and will send the crunch
3682     * response later.
3683     */
3684    if (
3685 #ifdef FEATURE_HTTPS_INSPECTION
3686        !client_use_ssl(csp) &&
3687 #endif
3688        crunch_response_triggered(csp, crunchers_all))
3689    {
3690       /*
3691        * Yes. The client got the crunch response and we're done here.
3692        */
3693       return;
3694    }
3695
3696    log_applied_actions(csp->action);
3697    log_error(LOG_LEVEL_GPC, "%s%s", http->hostport, http->path);
3698
3699    if (fwd->forward_host)
3700    {
3701       log_error(LOG_LEVEL_CONNECT, "via [%s]:%d to: %s",
3702          fwd->forward_host, fwd->forward_port, http->hostport);
3703    }
3704    else
3705    {
3706       log_error(LOG_LEVEL_CONNECT, "to %s", http->hostport);
3707    }
3708
3709    /* here we connect to the server, gateway, or the forwarder */
3710
3711 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3712    if ((csp->server_connection.sfd != JB_INVALID_SOCKET)
3713       && socket_is_still_alive(csp->server_connection.sfd)
3714       && connection_destination_matches(&csp->server_connection, http, fwd))
3715    {
3716       log_error(LOG_LEVEL_CONNECT,
3717          "Reusing server socket %d connected to %s. Total requests: %u.",
3718          csp->server_connection.sfd, csp->server_connection.host,
3719          csp->server_connection.requests_sent_total);
3720    }
3721    else
3722    {
3723       if (csp->server_connection.sfd != JB_INVALID_SOCKET)
3724       {
3725 #ifdef FEATURE_CONNECTION_SHARING
3726          if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
3727          {
3728             remember_connection(&csp->server_connection);
3729          }
3730          else
3731 #endif /* def FEATURE_CONNECTION_SHARING */
3732          {
3733             log_error(LOG_LEVEL_CONNECT,
3734                "Closing server socket %d connected to %s. Total requests: %u.",
3735                csp->server_connection.sfd, csp->server_connection.host,
3736                csp->server_connection.requests_sent_total);
3737             close_socket(csp->server_connection.sfd);
3738          }
3739          mark_connection_closed(&csp->server_connection);
3740       }
3741 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3742 #ifdef FEATURE_HTTPS_INSPECTION
3743       if (http->ssl && !use_ssl_tunnel)
3744       {
3745          int ret;
3746          /*
3747           * Creating an SSL proxy. If forwarding is disabled, we must send
3748           * CSUCCEED mesage to client. Then TLS/SSL connection with client
3749           * is created.
3750           */
3751
3752          if (fwd->forward_host == NULL)
3753          {
3754             /*
3755              * We're lying to the client as the connection hasn't actually
3756              * been established yet. We don't establish the connection until
3757              * we have seen and parsed the encrypted client headers.
3758              */
3759             if (write_socket_delayed(csp->cfd, CSUCCEED,
3760                   strlen(CSUCCEED), get_write_delay(csp)) != 0)
3761             {
3762                log_error(LOG_LEVEL_ERROR, "Sending SUCCEED to client failed");
3763                return;
3764             }
3765          }
3766
3767          ret = create_client_ssl_connection(csp);
3768          if (ret != 0)
3769          {
3770             log_error(LOG_LEVEL_ERROR,
3771                "Can't open secure connection with client");
3772             close_client_ssl_connection(csp); /* XXX: Is this needed? */
3773             return;
3774          }
3775          if (JB_ERR_OK != process_encrypted_request(csp))
3776          {
3777             log_error(LOG_LEVEL_ERROR, "Failed to parse encrypted request.");
3778             close_client_ssl_connection(csp);
3779             return;
3780          }
3781          /*
3782           * We have an encrypted request. Check if one of the crunchers now
3783           * wants it (for example because the previously invisible path was
3784           * required to match).
3785           */
3786          if (crunch_response_triggered(csp, crunchers_all))
3787          {
3788             /*
3789              * Yes. The client got the crunch response and we're done here.
3790              */
3791             close_client_ssl_connection(csp);
3792             return;
3793          }
3794       }
3795 #endif
3796       /*
3797        * Connecting to destination server
3798        */
3799       csp->server_connection.sfd = forwarded_connect(fwd, http, csp);
3800
3801       if (csp->server_connection.sfd == JB_INVALID_SOCKET)
3802       {
3803          if (fwd->type != SOCKS_NONE)
3804          {
3805             /* Socks error. */
3806             rsp = error_response(csp, "forwarding-failed");
3807          }
3808          else if (errno == EINVAL)
3809          {
3810             rsp = error_response(csp, "no-such-domain");
3811          }
3812          else
3813          {
3814             rsp = error_response(csp, "connect-failed");
3815          }
3816
3817          /* Write the answer to the client */
3818          if (rsp != NULL)
3819          {
3820             send_crunch_response(csp, rsp);
3821          }
3822
3823          /*
3824           * Temporary workaround to prevent already-read client
3825           * bodies from being parsed as new requests. For now we
3826           * err on the safe side and throw all the following
3827           * requests under the bus, even if no client body has been
3828           * buffered. A compliant client will repeat the dropped
3829           * requests on an untainted connection.
3830           *
3831           * The proper fix is to discard the no longer needed
3832           * client body in the buffer (if there is one) and to
3833           * continue parsing the bytes that follow.
3834           */
3835          drain_and_close_socket(csp->cfd);
3836          csp->cfd = JB_INVALID_SOCKET;
3837
3838          return;
3839       }
3840
3841 #ifdef FEATURE_HTTPS_INSPECTION
3842       /*
3843        * Creating TLS/SSL connections with destination server or parent
3844        * proxy. If forwarding is enabled, we must send client request to
3845        * parent proxy and receive, parse and resend parent proxy answer.
3846        */
3847       if (http->ssl && !use_ssl_tunnel)
3848       {
3849          if (fwd->forward_host != NULL)
3850          {
3851             char server_response[BUFFER_SIZE];
3852             int ret = 0;
3853             int len = 0;
3854             char *hdr = list_to_text(csp->headers);
3855             memset(server_response, 0, sizeof(server_response));
3856
3857             if (hdr == NULL)
3858             {
3859                log_error(LOG_LEVEL_FATAL,
3860                   "Out of memory parsing client header");
3861             }
3862             list_remove_all(csp->headers);
3863
3864             /*
3865              * Sending client's CONNECT request to the parent proxy
3866              */
3867             ret = write_socket(csp->server_connection.sfd, hdr, strlen(hdr));
3868
3869             freez(hdr);
3870
3871             if (ret != 0)
3872             {
3873                log_error(LOG_LEVEL_CONNECT,
3874                   "Sending request headers to: %s failed", http->hostport);
3875                mark_server_socket_tainted(csp);
3876                close_client_ssl_connection(csp);
3877                return;
3878             }
3879
3880             /* Waiting for parent proxy server response */
3881             len = read_socket(csp->server_connection.sfd, server_response,
3882                sizeof(server_response)-1);
3883
3884             if (len <= 0)
3885             {
3886                log_error(LOG_LEVEL_ERROR, "No response from parent proxy "
3887                   "server on socket %d.", csp->server_connection.sfd);
3888
3889                rsp = error_response(csp, "no-server-data");
3890                if (rsp)
3891                {
3892                   send_crunch_response(csp, rsp);
3893                }
3894                mark_server_socket_tainted(csp);
3895                close_client_ssl_connection(csp);
3896                return;
3897             }
3898
3899             /*
3900              * Test if connection with destination server was established
3901              * successfully by parent proxy. Then we can send response to
3902              * the client and continue or stop.
3903              */
3904             if (!tunnel_established_successfully(server_response, (unsigned int)len))
3905             {
3906                log_error(LOG_LEVEL_ERROR, "Forwarder hasn't established "
3907                   "connection with destination server.");
3908
3909                write_socket(csp->cfd, server_response, (size_t)len);
3910                mark_server_socket_tainted(csp);
3911                close_client_ssl_connection(csp);
3912                return;
3913             }
3914
3915             /*
3916              * Parent proxy has established connection with destination server.
3917              * Now we must create TLS/SSL connection with parent proxy.
3918              */
3919             ret = create_server_ssl_connection(csp);
3920
3921             /*
3922             * If TLS/SSL connection wasn't created and invalid certificate
3923             * wasn't detected, we can interrupt this function. Otherwise, we
3924             * must inform the client about invalid server certificate.
3925             */
3926             if (ret != 0
3927                && (csp->server_cert_verification_result == SSL_CERT_NOT_VERIFIED
3928                   || csp->server_cert_verification_result == SSL_CERT_VALID))
3929             {
3930                rsp = error_response(csp, "connect-failed");
3931                if (rsp)
3932                {
3933                   send_crunch_response(csp, rsp);
3934                }
3935                return;
3936             }
3937
3938             /*
3939              * TLS/SSL connection with parent proxy is established, we can
3940              * inform client about success.
3941              */
3942             ret = write_socket(csp->cfd, server_response, (size_t)len);
3943             if (ret != 0)
3944             {
3945                log_error(LOG_LEVEL_ERROR,
3946                   "Sending parent proxy response to client failed");
3947                mark_server_socket_tainted(csp);
3948                close_client_ssl_connection(csp);
3949                return;
3950             }
3951          }/* -END- if (fwd->forward_host != NULL) */
3952          else
3953          {
3954             /*
3955              * Parent proxy is not used, we can just create TLS/SSL connection
3956              * with destination server
3957              */
3958             int ret = create_server_ssl_connection(csp);
3959             if (ret != 0)
3960             {
3961                if (csp->server_cert_verification_result != SSL_CERT_VALID &&
3962                    csp->server_cert_verification_result != SSL_CERT_NOT_VERIFIED)
3963                {
3964                   /*
3965                    * If the server certificate is invalid, we must inform
3966                    * the client and then close connection to the client.
3967                    */
3968                   ssl_send_certificate_error(csp);
3969                   close_client_and_server_ssl_connections(csp);
3970                   return;
3971                }
3972                if (csp->server_cert_verification_result == SSL_CERT_NOT_VERIFIED
3973                 || csp->server_cert_verification_result == SSL_CERT_VALID)
3974                {
3975                   /*
3976                    * The TLS/SSL connection wasn't created but an invalid
3977                    * certificate wasn't detected. Report it as connection
3978                    * failure.
3979                    */
3980                   rsp = error_response(csp, "connect-failed");
3981                   if (rsp)
3982                   {
3983                      send_crunch_response(csp, rsp);
3984                   }
3985                   return;
3986                }
3987             }
3988          }
3989       }/* -END- if (http->ssl) */
3990 #endif /* def FEATURE_HTTPS_INSPECTION */
3991
3992 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3993       save_connection_destination(csp->server_connection.sfd,
3994          http, fwd, &csp->server_connection);
3995       csp->server_connection.keep_alive_timeout =
3996          (unsigned)csp->config->keep_alive_timeout;
3997    }
3998 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3999
4000    csp->server_connection.requests_sent_total++;
4001
4002    if ((fwd->type == SOCKS_5T) && (NULL == csp->headers->first))
4003    {
4004       /* Client headers have been sent optimistically */
4005       assert(csp->headers->last == NULL);
4006    }
4007    else if (http->ssl == 0 || (fwd->forward_host
4008 #ifdef FEATURE_HTTPS_INSPECTION
4009          && use_ssl_tunnel
4010 #endif
4011            ))
4012    {
4013       if (send_http_request(csp))
4014       {
4015          rsp = error_response(csp, "connect-failed");
4016          if (rsp)
4017          {
4018             send_crunch_response(csp, rsp);
4019          }
4020          return;
4021       }
4022    }
4023    else
4024    {
4025       /*
4026        * Using old solution with SSL tunnel or new solution with SSL proxy
4027        */
4028       list_remove_all(csp->headers);
4029 #ifdef FEATURE_HTTPS_INSPECTION
4030       if (use_ssl_tunnel)
4031 #endif
4032       {
4033          /*
4034          * We're running an SSL tunnel and we're not forwarding,
4035          * so just ditch the client headers, send the "connect succeeded"
4036          * message to the client, flush the rest, and get out of the way.
4037          */
4038          if (write_socket_delayed(csp->cfd, CSUCCEED,
4039                strlen(CSUCCEED), get_write_delay(csp)))
4040          {
4041             return;
4042          }
4043       }
4044 #ifdef FEATURE_HTTPS_INSPECTION
4045       else
4046       {
4047          /*
4048           * If server certificate is invalid, we must inform client and then
4049           * close connection with client.
4050           */
4051          if (csp->server_cert_verification_result != SSL_CERT_VALID)
4052          {
4053             ssl_send_certificate_error(csp);
4054             close_client_and_server_ssl_connections(csp);
4055             return;
4056          }
4057          if (send_https_request(csp))
4058          {
4059             rsp = error_response(csp, "connect-failed");
4060             if (rsp)
4061             {
4062                send_crunch_response(csp, rsp);
4063             }
4064             close_client_and_server_ssl_connections(csp);
4065             return;
4066          }
4067       }
4068 #endif /* def FEATURE_HTTPS_INSPECTION */
4069       clear_iob(csp->client_iob);
4070    }/* -END- else ... if (http->ssl == 1) */
4071
4072    log_error(LOG_LEVEL_CONNECT, "to %s successful", http->hostport);
4073
4074    /* XXX: should the time start earlier for optimistically sent data? */
4075    csp->server_connection.request_sent = time(NULL);
4076
4077    handle_established_connection(csp);
4078    freez(csp->receive_buffer);
4079 }
4080
4081
4082 #ifdef FUZZ
4083 /*********************************************************************
4084  *
4085  * Function    :  fuzz_server_response
4086  *
4087  * Description :  Treat the input as a whole server response.
4088  *
4089  * Parameters  :
4090  *          1  :  csp = Current client state (buffers, headers, etc...)
4091  *          2  :  fuzz_input_file = File to read the input from.
4092  *
4093  * Returns     :  0
4094  *
4095  *********************************************************************/
4096 extern int fuzz_server_response(struct client_state *csp, char *fuzz_input_file)
4097 {
4098    static struct forward_spec fwd; /* Zero'd due to being static */
4099    csp->cfd = 0;
4100
4101    if (strcmp(fuzz_input_file, "-") == 0)
4102    {
4103       /* XXX: Doesn'T work yet. */
4104       csp->server_connection.sfd = 0;
4105    }
4106    else
4107    {
4108       csp->server_connection.sfd = open(fuzz_input_file, O_RDONLY);
4109       if (csp->server_connection.sfd == -1)
4110       {
4111          log_error(LOG_LEVEL_FATAL, "Failed to open %s: %E",
4112             fuzz_input_file);
4113       }
4114    }
4115    csp->fwd = &fwd;
4116    csp->content_type |= CT_GIF;
4117    csp->action->flags |= ACTION_DEANIMATE;
4118    csp->action->string[ACTION_STRING_DEANIMATE] = "last";
4119
4120    csp->http->path = strdup_or_die("/");
4121    csp->http->host = strdup_or_die("fuzz.example.org");
4122    csp->http->hostport = strdup_or_die("fuzz.example.org:80");
4123    /* Prevent client socket monitoring */
4124    csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
4125    csp->flags |= CSP_FLAG_CHUNKED;
4126
4127    csp->config->feature_flags |= RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE;
4128    csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
4129
4130    csp->content_type |= CT_DECLARED|CT_GIF;
4131
4132    csp->config->socket_timeout = 0;
4133
4134    cgi_init_error_messages();
4135
4136    handle_established_connection(csp);
4137    freez(csp->receive_buffer);
4138
4139    return 0;
4140 }
4141 #endif
4142
4143
4144 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4145 /*********************************************************************
4146  *
4147  * Function    :  prepare_csp_for_next_request
4148  *
4149  * Description :  Put the csp in a mostly vergin state.
4150  *
4151  * Parameters  :
4152  *          1  :  csp = Current client state (buffers, headers, etc...)
4153  *
4154  * Returns     :  N/A
4155  *
4156  *********************************************************************/
4157 static void prepare_csp_for_next_request(struct client_state *csp)
4158 {
4159    csp->content_type = 0;
4160    csp->content_length = 0;
4161    csp->expected_content_length = 0;
4162    csp->expected_client_content_length = 0;
4163    list_remove_all(csp->headers);
4164    clear_iob(csp->iob);
4165    freez(csp->error_message);
4166    free_http_request(csp->http);
4167    destroy_list(csp->headers);
4168    destroy_list(csp->tags);
4169 #ifdef FEATURE_CLIENT_TAGS
4170    destroy_list(csp->client_tags);
4171    freez(csp->client_address);
4172 #endif
4173    free_current_action(csp->action);
4174    if (NULL != csp->fwd)
4175    {
4176       unload_forward_spec(csp->fwd);
4177       csp->fwd = NULL;
4178    }
4179    /* XXX: Store per-connection flags someplace else. */
4180    csp->flags = (CSP_FLAG_ACTIVE | CSP_FLAG_REUSED_CLIENT_CONNECTION);
4181 #ifdef FEATURE_TOGGLE
4182    if (global_toggle_state)
4183 #endif /* def FEATURE_TOGGLE */
4184    {
4185       csp->flags |= CSP_FLAG_TOGGLED_ON;
4186    }
4187
4188    if (csp->client_iob->eod > csp->client_iob->cur)
4189    {
4190       long bytes_to_shift = csp->client_iob->cur - csp->client_iob->buf;
4191       size_t data_length  = (size_t)(csp->client_iob->eod - csp->client_iob->cur);
4192
4193       assert(bytes_to_shift > 0);
4194       assert(data_length > 0);
4195
4196       log_error(LOG_LEVEL_CONNECT, "Shifting %d pipelined bytes by %d bytes",
4197          data_length, bytes_to_shift);
4198       memmove(csp->client_iob->buf, csp->client_iob->cur, data_length);
4199       csp->client_iob->cur = csp->client_iob->buf;
4200       assert(csp->client_iob->eod == csp->client_iob->buf + bytes_to_shift + data_length);
4201       csp->client_iob->eod = csp->client_iob->buf + data_length;
4202       memset(csp->client_iob->eod, '\0', (size_t)bytes_to_shift);
4203
4204       csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
4205    }
4206    else
4207    {
4208       /*
4209        * We mainly care about resetting client_iob->cur so we don't
4210        * waste buffer space at the beginning and don't mess up the
4211        * request restoration done by cgi_show_request().
4212        *
4213        * Freeing the buffer itself isn't technically necessary,
4214        * but makes debugging more convenient.
4215        */
4216       clear_iob(csp->client_iob);
4217    }
4218 }
4219 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
4220
4221
4222 /*********************************************************************
4223  *
4224  * Function    :  serve
4225  *
4226  * Description :  This is little more than chat.  We only "serve" to
4227  *                to close (or remember) any socket that chat may have
4228  *                opened.
4229  *
4230  * Parameters  :
4231  *          1  :  csp = Current client state (buffers, headers, etc...)
4232  *
4233  * Returns     :  N/A
4234  *
4235  *********************************************************************/
4236 static void serve(struct client_state *csp)
4237 {
4238    int config_file_change_detected = 0; /* Only used for debugging */
4239 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4240 #ifdef FEATURE_CONNECTION_SHARING
4241    static int monitor_thread_running = 0;
4242 #endif /* def FEATURE_CONNECTION_SHARING */
4243    int continue_chatting = 0;
4244
4245    log_error(LOG_LEVEL_CONNECT, "Accepted connection from %s on socket %d",
4246       csp->ip_addr_str, csp->cfd);
4247
4248    do
4249    {
4250       unsigned int latency;
4251
4252       chat(csp);
4253
4254       /*
4255        * If the request has been crunched,
4256        * the calculated latency is zero.
4257        */
4258       latency = (unsigned)(csp->server_connection.response_received -
4259          csp->server_connection.request_sent) / 2;
4260
4261       if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4262          && (csp->flags & CSP_FLAG_CRUNCHED)
4263          && (csp->expected_client_content_length != 0))
4264       {
4265          csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
4266          log_error(LOG_LEVEL_CONNECT,
4267             "Tainting client socket %d due to unread data.", csp->cfd);
4268       }
4269
4270       continue_chatting = (csp->config->feature_flags
4271          & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
4272          && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4273          && (csp->cfd != JB_INVALID_SOCKET)
4274          && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4275          && ((csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET)
4276             || (csp->flags & CSP_FLAG_CHUNKED));
4277
4278       if (!(csp->flags & CSP_FLAG_CRUNCHED)
4279          && (csp->server_connection.sfd != JB_INVALID_SOCKET))
4280       {
4281          if (!(csp->flags & CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET))
4282          {
4283             csp->server_connection.keep_alive_timeout = csp->config->default_server_timeout;
4284          }
4285          if (!(csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE)
4286             || (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4287             || !socket_is_still_alive(csp->server_connection.sfd)
4288             || !(latency < csp->server_connection.keep_alive_timeout))
4289          {
4290             log_error(LOG_LEVEL_CONNECT,
4291                "Closing server socket %d connected to %s. "
4292                "Keep-alive %u. Tainted: %u. Socket alive %u. Timeout: %u.",
4293                csp->server_connection.sfd, csp->server_connection.host,
4294                0 != (csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE),
4295                0 != (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED),
4296                socket_is_still_alive(csp->server_connection.sfd),
4297                csp->server_connection.keep_alive_timeout);
4298 #ifdef FEATURE_CONNECTION_SHARING
4299             if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4300             {
4301                forget_connection(csp->server_connection.sfd);
4302             }
4303 #endif /* def FEATURE_CONNECTION_SHARING */
4304             close_socket(csp->server_connection.sfd);
4305             mark_connection_closed(&csp->server_connection);
4306          }
4307       }
4308
4309       if (continue_chatting && any_loaded_file_changed(csp))
4310       {
4311          continue_chatting = 0;
4312          config_file_change_detected = 1;
4313       }
4314
4315       if (continue_chatting)
4316       {
4317          if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) != 0)
4318             && socket_is_still_alive(csp->cfd))
4319          {
4320             log_error(LOG_LEVEL_CONNECT, "Client request %d has been "
4321                "pipelined on socket %d and the socket is still alive.",
4322                csp->requests_received_total+1, csp->cfd);
4323             prepare_csp_for_next_request(csp);
4324             continue;
4325          }
4326
4327          if (0 != (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE))
4328          {
4329             if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4330             {
4331                log_error(LOG_LEVEL_CONNECT,
4332                   "Waiting for the next client request on socket %d. "
4333                   "Keeping the server socket %d to %s open.",
4334                   csp->cfd, csp->server_connection.sfd, csp->server_connection.host);
4335             }
4336             else
4337             {
4338                log_error(LOG_LEVEL_CONNECT,
4339                   "Waiting for the next client request on socket %d. "
4340                   "No server socket to keep open.", csp->cfd);
4341             }
4342          }
4343
4344          if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4345             && data_is_available(csp->cfd, (int)csp->config->keep_alive_timeout)
4346             && socket_is_still_alive(csp->cfd))
4347          {
4348             log_error(LOG_LEVEL_CONNECT,
4349                "Client request %u arrived in time on socket %d.",
4350                csp->requests_received_total+1, csp->cfd);
4351             prepare_csp_for_next_request(csp);
4352          }
4353          else
4354          {
4355 #ifdef FEATURE_CONNECTION_SHARING
4356             if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4357                && (csp->server_connection.sfd != JB_INVALID_SOCKET)
4358                && (socket_is_still_alive(csp->server_connection.sfd)))
4359             {
4360                time_t time_open = time(NULL) - csp->server_connection.timestamp;
4361
4362                if (csp->server_connection.keep_alive_timeout < time_open - (time_t)latency)
4363                {
4364                   break;
4365                }
4366
4367                remember_connection(&csp->server_connection);
4368                csp->server_connection.sfd = JB_INVALID_SOCKET;
4369                drain_and_close_socket(csp->cfd);
4370                csp->cfd = JB_INVALID_SOCKET;
4371                privoxy_mutex_lock(&connection_reuse_mutex);
4372                if (!monitor_thread_running)
4373                {
4374                   monitor_thread_running = 1;
4375                   privoxy_mutex_unlock(&connection_reuse_mutex);
4376                   wait_for_alive_connections();
4377                   privoxy_mutex_lock(&connection_reuse_mutex);
4378                   monitor_thread_running = 0;
4379                }
4380                privoxy_mutex_unlock(&connection_reuse_mutex);
4381             }
4382 #endif /* def FEATURE_CONNECTION_SHARING */
4383             break;
4384          }
4385       }
4386       else if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4387       {
4388          log_error(LOG_LEVEL_CONNECT,
4389             "Closing server socket %d connected to %s. Keep-alive: %u. "
4390             "Tainted: %u. Socket alive: %u. Timeout: %u. "
4391             "Configuration file change detected: %u",
4392             csp->server_connection.sfd, csp->server_connection.host,
4393             0 != (csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE),
4394             0 != (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED),
4395             socket_is_still_alive(csp->server_connection.sfd),
4396             csp->server_connection.keep_alive_timeout,
4397             config_file_change_detected);
4398       }
4399    } while (continue_chatting);
4400
4401 #else
4402    chat(csp);
4403 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
4404
4405    if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4406    {
4407 #ifdef FEATURE_CONNECTION_SHARING
4408       if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4409       {
4410          forget_connection(csp->server_connection.sfd);
4411       }
4412 #endif /* def FEATURE_CONNECTION_SHARING */
4413       close_socket(csp->server_connection.sfd);
4414    }
4415
4416 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4417    mark_connection_closed(&csp->server_connection);
4418 #endif
4419
4420    if (csp->cfd != JB_INVALID_SOCKET)
4421    {
4422       log_error(LOG_LEVEL_CONNECT, "Closing client socket %d. "
4423          "Keep-alive: %u. Socket alive: %u. Data available: %u. "
4424          "Configuration file change detected: %u. Requests received: %u.",
4425          csp->cfd, 0 != (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE),
4426          socket_is_still_alive(csp->cfd), data_is_available(csp->cfd, 0),
4427          config_file_change_detected, csp->requests_received_total);
4428       drain_and_close_socket(csp->cfd);
4429    }
4430
4431    free_csp_resources(csp);
4432
4433    csp->flags &= ~CSP_FLAG_ACTIVE;
4434
4435 }
4436
4437
4438 #ifdef __BEOS__
4439 /*********************************************************************
4440  *
4441  * Function    :  server_thread
4442  *
4443  * Description :  We only exist to call `serve' in a threaded environment.
4444  *
4445  * Parameters  :
4446  *          1  :  data = Current client state (buffers, headers, etc...)
4447  *
4448  * Returns     :  Always 0.
4449  *
4450  *********************************************************************/
4451 static int32 server_thread(void *data)
4452 {
4453    serve((struct client_state *) data);
4454    return 0;
4455
4456 }
4457 #endif
4458
4459
4460 #if !defined(_WIN32) || defined(_WIN_CONSOLE)
4461 /*********************************************************************
4462  *
4463  * Function    :  usage
4464  *
4465  * Description :  Print usage info & exit.
4466  *
4467  * Parameters  :  Pointer to argv[0] for identifying ourselves
4468  *
4469  * Returns     :  No. ,-)
4470  *
4471  *********************************************************************/
4472 static void usage(const char *name)
4473 {
4474    printf("Privoxy version " VERSION " (" HOME_PAGE_URL ")\n"
4475           "Usage: %s [--config-test] "
4476 #if defined(unix)
4477           "[--chroot]&nbs