a5174b3047dc2f6de3601eb9c100a24dc3c5297f
[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 LIMIT_MUTEX_NUMBER
197 privoxy_mutex_t certificates_mutexes[32];
198 #else
199 privoxy_mutex_t certificates_mutexes[65536];
200 #endif /* LIMIT_MUTEX_NUMBER */
201 privoxy_mutex_t rng_mutex;
202
203 #ifdef FEATURE_EXTERNAL_FILTERS
204 privoxy_mutex_t external_filter_mutex;
205 #endif
206 #ifdef FEATURE_CLIENT_TAGS
207 privoxy_mutex_t client_tags_mutex;
208 #endif
209
210 #if !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R)
211 privoxy_mutex_t resolver_mutex;
212 #endif /* !defined(HAVE_GETHOSTBYADDR_R) || !defined(HAVE_GETHOSTBYNAME_R) */
213
214 #ifndef HAVE_GMTIME_R
215 privoxy_mutex_t gmtime_mutex;
216 #endif /* ndef HAVE_GMTIME_R */
217
218 #ifndef HAVE_LOCALTIME_R
219 privoxy_mutex_t localtime_mutex;
220 #endif /* ndef HAVE_GMTIME_R */
221
222 #if !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM)
223 privoxy_mutex_t rand_mutex;
224 #endif /* !defined(HAVE_ARC4RANDOM) && !defined(HAVE_RANDOM) */
225
226 #endif /* def MUTEX_LOCKS_AVAILABLE */
227
228 #if defined(unix)
229 const char *basedir = NULL;
230 const char *pidfile = NULL;
231 static int received_hup_signal = 0;
232 #endif /* defined unix */
233
234 /* HTTP snipplets. */
235 static const char CSUCCEED[] =
236    "HTTP/1.1 200 Connection established\r\n\r\n";
237
238 static const char CHEADER[] =
239    "HTTP/1.1 400 Invalid header received from client\r\n"
240    "Content-Type: text/plain\r\n"
241    "Connection: close\r\n\r\n"
242    "Invalid header received from client.\r\n";
243
244 static const char FTP_RESPONSE[] =
245    "HTTP/1.1 400 Invalid request received from client\r\n"
246    "Content-Type: text/plain\r\n"
247    "Connection: close\r\n\r\n"
248    "Invalid request. Privoxy doesn't support FTP.\r\n";
249
250 static const char GOPHER_RESPONSE[] =
251    "HTTP/1.1 400 Invalid request received from client\r\n"
252    "Content-Type: text/plain\r\n"
253    "Connection: close\r\n\r\n"
254    "Invalid request. Privoxy doesn't support gopher.\r\n";
255
256 /* XXX: should be a template */
257 static const char MISSING_DESTINATION_RESPONSE[] =
258    "HTTP/1.1 400 Bad request received from client\r\n"
259    "Content-Type: text/plain\r\n"
260    "Connection: close\r\n\r\n"
261    "Bad request. Privoxy was unable to extract the destination.\r\n";
262
263 /* XXX: should be a template */
264 static const char INVALID_SERVER_HEADERS_RESPONSE[] =
265    "HTTP/1.1 502 Server or forwarder response invalid\r\n"
266    "Content-Type: text/plain\r\n"
267    "Connection: close\r\n\r\n"
268    "Bad response. The server or forwarder response doesn't look like HTTP.\r\n";
269
270 /* XXX: should be a template */
271 static const char MESSED_UP_REQUEST_RESPONSE[] =
272    "HTTP/1.1 400 Malformed request after rewriting\r\n"
273    "Content-Type: text/plain\r\n"
274    "Connection: close\r\n\r\n"
275    "Bad request. Messed up with header filters.\r\n";
276
277 static const char TOO_MANY_CONNECTIONS_RESPONSE[] =
278    "HTTP/1.1 503 Too many open connections\r\n"
279    "Content-Type: text/plain\r\n"
280    "Connection: close\r\n\r\n"
281    "Maximum number of open connections reached.\r\n";
282
283 static const char CLIENT_CONNECTION_TIMEOUT_RESPONSE[] =
284    "HTTP/1.1 504 Connection timeout\r\n"
285    "Content-Type: text/plain\r\n"
286    "Connection: close\r\n\r\n"
287    "The connection timed out because the client request didn't arrive in time.\r\n";
288
289 static const char CLIENT_BODY_PARSE_ERROR_RESPONSE[] =
290    "HTTP/1.1 400 Failed reading client body\r\n"
291    "Content-Type: text/plain\r\n"
292    "Connection: close\r\n\r\n"
293    "Failed parsing or buffering the chunk-encoded client body.\r\n";
294
295 static const char UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE[] =
296    "HTTP/1.1 417 Expecting too much\r\n"
297    "Content-Type: text/plain\r\n"
298    "Connection: close\r\n\r\n"
299    "Privoxy detected an unsupported Expect header value.\r\n";
300
301 /* A function to crunch a response */
302 typedef struct http_response *(*crunch_func_ptr)(struct client_state *);
303
304 /* Crunch function flags */
305 #define CF_NO_FLAGS        0
306 /* Cruncher applies to forced requests as well */
307 #define CF_IGNORE_FORCE    1
308 /* Crunched requests are counted for the block statistics */
309 #define CF_COUNT_AS_REJECT 2
310
311 /* A crunch function and its flags */
312 struct cruncher
313 {
314    const crunch_func_ptr cruncher;
315    const int flags;
316 };
317
318 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[]);
319
320 /* Complete list of cruncher functions */
321 static const struct cruncher crunchers_all[] = {
322    { direct_response, CF_COUNT_AS_REJECT|CF_IGNORE_FORCE},
323    { block_url,       CF_COUNT_AS_REJECT },
324 #ifdef FEATURE_TRUST
325    { trust_url,       CF_COUNT_AS_REJECT },
326 #endif /* def FEATURE_TRUST */
327    { redirect_url,    CF_NO_FLAGS  },
328    { dispatch_cgi,    CF_IGNORE_FORCE},
329    { NULL,            0 }
330 };
331
332 /* Light version, used after tags are applied */
333 static const struct cruncher crunchers_light[] = {
334    { block_url,       CF_COUNT_AS_REJECT },
335    { redirect_url,    CF_NO_FLAGS },
336    { NULL,            0 }
337 };
338
339
340 /*
341  * XXX: Don't we really mean
342  *
343  * #if defined(unix)
344  *
345  * here?
346  */
347 #if !defined(_WIN32) && !defined(__OS2__)
348 /*********************************************************************
349  *
350  * Function    :  sig_handler
351  *
352  * Description :  Signal handler for different signals.
353  *                Exit gracefully on TERM and INT
354  *                or set a flag that will cause the errlog
355  *                to be reopened by the main thread on HUP.
356  *
357  * Parameters  :
358  *          1  :  the_signal = the signal cause this function to call
359  *
360  * Returns     :  -
361  *
362  *********************************************************************/
363 static void sig_handler(int the_signal)
364 {
365    switch(the_signal)
366    {
367       case SIGTERM:
368       case SIGINT:
369          log_error(LOG_LEVEL_INFO, "exiting by signal %d .. bye", the_signal);
370 #if defined(unix)
371          if (pidfile)
372          {
373             unlink(pidfile);
374          }
375 #endif /* unix */
376          exit(the_signal);
377          break;
378
379       case SIGHUP:
380 #if defined(unix)
381          received_hup_signal = 1;
382 #endif
383          break;
384
385       default:
386          /*
387           * We shouldn't be here, unless we catch signals
388           * in main() that we can't handle here!
389           */
390          log_error(LOG_LEVEL_FATAL, "sig_handler: exiting on unexpected signal %d", the_signal);
391    }
392    return;
393
394 }
395 #endif
396
397
398 /*********************************************************************
399  *
400  * Function    :  get_write_delay
401  *
402  * Description :  Parse the delay-response parameter.
403  *
404  * Parameters  :
405  *          1  :  csp = Current client state (buffers, headers, etc...)
406  *
407  * Returns     :  Number of milliseconds to delay writes.
408  *
409  *********************************************************************/
410 static unsigned int get_write_delay(const struct client_state *csp)
411 {
412    unsigned int delay;
413    char *endptr;
414    char *newval;
415
416    if ((csp->action->flags & ACTION_DELAY_RESPONSE) == 0)
417    {
418       return 0;
419    }
420    newval = csp->action->string[ACTION_STRING_DELAY_RESPONSE];
421
422    delay = (unsigned)strtol(newval, &endptr, 0);
423    if (*endptr != '\0')
424    {
425       log_error(LOG_LEVEL_FATAL,
426          "Invalid delay-response{} parameter: '%s'", newval);
427    }
428
429    return delay;
430
431 }
432
433
434 /*********************************************************************
435  *
436  * Function    :  client_protocol_is_unsupported
437  *
438  * Description :  Checks if the client used a known unsupported
439  *                protocol and deals with it by sending an error
440  *                response.
441  *
442  * Parameters  :
443  *          1  :  csp = Current client state (buffers, headers, etc...)
444  *          2  :  req = the first request line send by the client
445  *
446  * Returns     :  TRUE if an error response has been generated, or
447  *                FALSE if the request doesn't look invalid.
448  *
449  *********************************************************************/
450 static int client_protocol_is_unsupported(const struct client_state *csp, char *req)
451 {
452    /*
453     * If it's a FTP or gopher request, we don't support it.
454     *
455     * These checks are better than nothing, but they might
456     * not work in all configurations and some clients might
457     * have problems digesting the answer.
458     *
459     * They should, however, never cause more problems than
460     * Privoxy's old behaviour (returning the misleading HTML
461     * error message:
462     *
463     * "Could not resolve http://(ftp|gopher)://example.org").
464     */
465    if (!strncmpic(req, "GET ftp://", 10) || !strncmpic(req, "GET gopher://", 13))
466    {
467       const char *response = NULL;
468       const char *protocol = NULL;
469
470       if (!strncmpic(req, "GET ftp://", 10))
471       {
472          response = FTP_RESPONSE;
473          protocol = "FTP";
474       }
475       else
476       {
477          response = GOPHER_RESPONSE;
478          protocol = "GOPHER";
479       }
480       log_error(LOG_LEVEL_ERROR,
481          "%s tried to use Privoxy as %s proxy: %s",
482          csp->ip_addr_str, protocol, req);
483       log_error(LOG_LEVEL_CLF,
484          "%s - - [%T] \"%s\" 400 0", csp->ip_addr_str, req);
485       freez(req);
486       write_socket_delayed(csp->cfd, response, strlen(response),
487          get_write_delay(csp));
488
489       return TRUE;
490    }
491
492    return FALSE;
493 }
494
495
496 /*********************************************************************
497  *
498  * Function    :  client_has_unsupported_expectations
499  *
500  * Description :  Checks if the client used an unsupported expectation
501  *                in which case an error message is delivered.
502  *
503  * Parameters  :
504  *          1  :  csp = Current client state (buffers, headers, etc...)
505  *
506  * Returns     :  TRUE if an error response has been generated, or
507  *                FALSE if the request doesn't look invalid.
508  *
509  *********************************************************************/
510 static int client_has_unsupported_expectations(const struct client_state *csp)
511 {
512    if ((csp->flags & CSP_FLAG_UNSUPPORTED_CLIENT_EXPECTATION))
513    {
514       log_error(LOG_LEVEL_ERROR,
515          "Rejecting request from client %s with unsupported Expect header value",
516          csp->ip_addr_str);
517       log_error(LOG_LEVEL_CLF,
518          "%s - - [%T] \"%s\" 417 0", csp->ip_addr_str, csp->http->cmd);
519       write_socket_delayed(csp->cfd,
520          UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE,
521          strlen(UNSUPPORTED_CLIENT_EXPECTATION_ERROR_RESPONSE),
522          get_write_delay(csp));
523
524       return TRUE;
525    }
526
527    return FALSE;
528
529 }
530
531
532 /*********************************************************************
533  *
534  * Function    :  get_request_destination_elsewhere
535  *
536  * Description :  If the client's request was redirected into
537  *                Privoxy without the client's knowledge,
538  *                the request line lacks the destination host.
539  *
540  *                This function tries to get it elsewhere,
541  *                provided accept-intercepted-requests is enabled.
542  *
543  *                "Elsewhere" currently only means "Host: header",
544  *                but in the future we may ask the redirecting
545  *                packet filter to look the destination up.
546  *
547  *                If the destination stays unknown, an error
548  *                response is send to the client and headers
549  *                are freed so that chat() can return directly.
550  *
551  * Parameters  :
552  *          1  :  csp = Current client state (buffers, headers, etc...)
553  *          2  :  headers = a header list
554  *
555  * Returns     :  JB_ERR_OK if the destination is now known, or
556  *                JB_ERR_PARSE if it isn't.
557  *
558  *********************************************************************/
559 static jb_err get_request_destination_elsewhere(struct client_state *csp, struct list *headers)
560 {
561    char *req;
562
563    if (!(csp->config->feature_flags & RUNTIME_FEATURE_ACCEPT_INTERCEPTED_REQUESTS))
564    {
565       log_error(LOG_LEVEL_ERROR, "%s's request: \'%s\' is invalid."
566          " Privoxy isn't configured to accept intercepted requests.",
567          csp->ip_addr_str, csp->http->cmd);
568       /* XXX: Use correct size */
569       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
570          csp->ip_addr_str, csp->http->cmd);
571
572       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
573          get_write_delay(csp));
574       destroy_list(headers);
575
576       return JB_ERR_PARSE;
577    }
578    else if (JB_ERR_OK == get_destination_from_headers(headers, csp->http))
579    {
580 #ifndef FEATURE_EXTENDED_HOST_PATTERNS
581       /* Split the domain we just got for pattern matching */
582       init_domain_components(csp->http);
583 #endif
584
585       return JB_ERR_OK;
586    }
587    else
588    {
589       /* We can't work without destination. Go spread the news.*/
590
591       req = list_to_text(headers);
592       chomp(req);
593       /* XXX: Use correct size */
594       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
595          csp->ip_addr_str, csp->http->cmd);
596       log_error(LOG_LEVEL_ERROR,
597          "Privoxy was unable to get the destination for %s's request:\n%s\n%s",
598          csp->ip_addr_str, csp->http->cmd, req);
599       freez(req);
600
601       write_socket_delayed(csp->cfd, MISSING_DESTINATION_RESPONSE,
602          strlen(MISSING_DESTINATION_RESPONSE), get_write_delay(csp));
603       destroy_list(headers);
604
605       return JB_ERR_PARSE;
606    }
607    /*
608     * TODO: If available, use PF's ioctl DIOCNATLOOK as last resort
609     * to get the destination IP address, use it as host directly
610     * or do a reverse DNS lookup first.
611     */
612 }
613
614
615 /*********************************************************************
616  *
617  * Function    :  get_server_headers
618  *
619  * Description :  Parses server headers in iob and fills them
620  *                into csp->headers so that they can later be
621  *                handled by sed().
622  *
623  * Parameters  :
624  *          1  :  csp = Current client state (buffers, headers, etc...)
625  *
626  * Returns     :  JB_ERR_OK if everything went fine, or
627  *                JB_ERR_PARSE if the headers were incomplete.
628  *
629  *********************************************************************/
630 static jb_err get_server_headers(struct client_state *csp)
631 {
632    int continue_hack_in_da_house = 0;
633    char * header;
634
635    while (((header = get_header(csp->iob)) != NULL) || continue_hack_in_da_house)
636    {
637       if (header == NULL)
638       {
639          /*
640           * continue hack in da house. Ignore the ending of
641           * this head and continue enlisting header lines.
642           * The reason is described below.
643           */
644          enlist(csp->headers, "");
645          continue_hack_in_da_house = 0;
646          continue;
647       }
648       else if (0 == strncmpic(header, "HTTP/1.1 100", 12))
649       {
650          /*
651           * It's a bodyless continue response, don't
652           * stop header parsing after reaching its end.
653           *
654           * As a result Privoxy will concatenate the
655           * next response's head and parse and deliver
656           * the headers as if they belonged to one request.
657           *
658           * The client will separate them because of the
659           * empty line between them.
660           *
661           * XXX: What we're doing here is clearly against
662           * the intended purpose of the continue header,
663           * and under some conditions (HTTP/1.0 client request)
664           * it's a standard violation.
665           *
666           * Anyway, "sort of against the spec" is preferable
667           * to "always getting confused by Continue responses"
668           * (Privoxy's behaviour before this hack was added)
669           */
670          log_error(LOG_LEVEL_HEADER, "Continue hack in da house.");
671          continue_hack_in_da_house = 1;
672       }
673       else if (*header == '\0')
674       {
675          /*
676           * If the header is empty, but the Continue hack
677           * isn't active, we can assume that we reached the
678           * end of the buffer before we hit the end of the
679           * head.
680           *
681           * Inform the caller an let it decide how to handle it.
682           */
683          return JB_ERR_PARSE;
684       }
685
686       if (JB_ERR_MEMORY == enlist(csp->headers, header))
687       {
688          /*
689           * XXX: Should we quit the request and return a
690           * out of memory error page instead?
691           */
692          log_error(LOG_LEVEL_ERROR,
693             "Out of memory while enlisting server headers. %s lost.",
694             header);
695       }
696       freez(header);
697    }
698
699    return JB_ERR_OK;
700 }
701
702
703 /*********************************************************************
704  *
705  * Function    :  crunch_reason
706  *
707  * Description :  Translates the crunch reason code into a string.
708  *
709  * Parameters  :
710  *          1  :  rsp = a http_response
711  *
712  * Returns     :  A string with the crunch reason or an error description.
713  *
714  *********************************************************************/
715 static const char *crunch_reason(const struct http_response *rsp)
716 {
717    char * reason = NULL;
718
719    assert(rsp != NULL);
720    if (rsp == NULL)
721    {
722       return "Internal error while searching for crunch reason";
723    }
724
725    switch (rsp->crunch_reason)
726    {
727       case UNSUPPORTED:
728          reason = "Unsupported HTTP feature";
729          break;
730       case BLOCKED:
731          reason = "Blocked";
732          break;
733       case UNTRUSTED:
734          reason = "Untrusted";
735          break;
736       case REDIRECTED:
737          reason = "Redirected";
738          break;
739       case CGI_CALL:
740          reason = "CGI Call";
741          break;
742       case NO_SUCH_DOMAIN:
743          reason = "DNS failure";
744          break;
745       case FORWARDING_FAILED:
746          reason = "Forwarding failed";
747          break;
748       case CONNECT_FAILED:
749          reason = "Connection failure";
750          break;
751       case OUT_OF_MEMORY:
752          reason = "Out of memory (may mask other reasons)";
753          break;
754       case CONNECTION_TIMEOUT:
755          reason = "Connection timeout";
756          break;
757       case NO_SERVER_DATA:
758          reason = "No server data received";
759          break;
760       default:
761          reason = "No reason recorded";
762          break;
763    }
764
765    return reason;
766 }
767
768
769 /*********************************************************************
770  *
771  * Function    :  log_applied_actions
772  *
773  * Description :  Logs the applied actions if LOG_LEVEL_ACTIONS is
774  *                enabled.
775  *
776  * Parameters  :
777  *          1  :  actions = Current action spec to log
778  *
779  * Returns     :  Nothing.
780  *
781  *********************************************************************/
782 static void log_applied_actions(const struct current_action_spec *actions)
783 {
784    /*
785     * The conversion to text requires lots of memory allocations so
786     * we only do the conversion if the user is actually interested.
787     */
788    if (debug_level_is_enabled(LOG_LEVEL_ACTIONS))
789    {
790       char *actions_as_text = actions_to_line_of_text(actions);
791       log_error(LOG_LEVEL_ACTIONS, "%s", actions_as_text);
792       freez(actions_as_text);
793    }
794 }
795
796
797 /*********************************************************************
798  *
799  * Function    :  send_crunch_response
800  *
801  * Description :  Delivers already prepared response for
802  *                intercepted requests, logs the interception
803  *                and frees the response.
804  *
805  * Parameters  :
806  *          1  :  csp = Current client state (buffers, headers, etc...)
807  *          2  :  rsp = Fully prepared response. Will be freed on exit.
808  *
809  * Returns     :  Nothing.
810  *
811  *********************************************************************/
812 static void send_crunch_response(struct client_state *csp, struct http_response *rsp)
813 {
814       const struct http_request *http = csp->http;
815       char status_code[4];
816
817       assert(rsp != NULL);
818       assert(rsp->head != NULL);
819
820       if (rsp == NULL)
821       {
822          log_error(LOG_LEVEL_FATAL, "NULL response in send_crunch_response.");
823       }
824
825       /*
826        * Extract the status code from the actual head
827        * that will be send to the client. It is the only
828        * way to get it right for all requests, including
829        * the fixed ones for out-of-memory problems.
830        *
831        * A head starts like this: 'HTTP/1.1 200...'
832        *                           0123456789|11
833        *                                     10
834        */
835       status_code[0] = rsp->head[9];
836       status_code[1] = rsp->head[10];
837       status_code[2] = rsp->head[11];
838       status_code[3] = '\0';
839
840       /* Log that the request was crunched and why. */
841       log_applied_actions(csp->action);
842       log_error(LOG_LEVEL_CRUNCH, "%s: %s", crunch_reason(rsp), http->url);
843       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" %s %u",
844          csp->ip_addr_str, http->ocmd, status_code, rsp->content_length);
845
846       /* Write the answer to the client */
847 #ifdef FEATURE_HTTPS_INSPECTION
848       if (client_use_ssl(csp))
849       {
850          if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
851                  (const unsigned char *)rsp->head, rsp->head_length) < 0)
852           || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
853                  (const unsigned char *)rsp->body, rsp->content_length) < 0))
854          {
855             /* There is nothing we can do about it. */
856             log_error(LOG_LEVEL_CONNECT, "Couldn't deliver the error message "
857                "for %s through client socket %d using TLS/SSL",
858                http->url, csp->cfd);
859          }
860       }
861       else
862 #endif
863       {
864          if (write_socket_delayed(csp->cfd, rsp->head, rsp->head_length,
865                 get_write_delay(csp))
866           || write_socket_delayed(csp->cfd, rsp->body, rsp->content_length,
867                 get_write_delay(csp)))
868          {
869             /* There is nothing we can do about it. */
870             log_error(LOG_LEVEL_CONNECT,
871                "Couldn't deliver the error message for %s through client socket %d: %E",
872                http->url, csp->cfd);
873          }
874       }
875
876       /* Clean up and return */
877       if (cgi_error_memory() != rsp)
878       {
879          free_http_response(rsp);
880       }
881       return;
882 }
883
884
885 /*********************************************************************
886  *
887  * Function    :  crunch_response_triggered
888  *
889  * Description :  Checks if the request has to be crunched,
890  *                and delivers the crunch response if necessary.
891  *
892  * Parameters  :
893  *          1  :  csp = Current client state (buffers, headers, etc...)
894  *          2  :  crunchers = list of cruncher functions to run
895  *
896  * Returns     :  TRUE if the request was answered with a crunch response
897  *                FALSE otherwise.
898  *
899  *********************************************************************/
900 static int crunch_response_triggered(struct client_state *csp, const struct cruncher crunchers[])
901 {
902    struct http_response *rsp = NULL;
903    const struct cruncher *c;
904
905    /*
906     * If CGI request crunching is disabled,
907     * check the CGI dispatcher out of order to
908     * prevent unintentional blocks or redirects.
909     */
910    if (!(csp->config->feature_flags & RUNTIME_FEATURE_CGI_CRUNCHING)
911        && (NULL != (rsp = dispatch_cgi(csp))))
912    {
913       /* Deliver, log and free the interception response. */
914       send_crunch_response(csp, rsp);
915       csp->flags |= CSP_FLAG_CRUNCHED;
916       return TRUE;
917    }
918
919    for (c = crunchers; c->cruncher != NULL; c++)
920    {
921       /*
922        * Check the cruncher if either Privoxy is toggled
923        * on and the request isn't forced, or if the cruncher
924        * applies to forced requests as well.
925        */
926       if (((csp->flags & CSP_FLAG_TOGGLED_ON) &&
927           !(csp->flags & CSP_FLAG_FORCED)) ||
928           (c->flags & CF_IGNORE_FORCE))
929       {
930          rsp = c->cruncher(csp);
931          if (NULL != rsp)
932          {
933             /* Deliver, log and free the interception response. */
934             send_crunch_response(csp, rsp);
935             csp->flags |= CSP_FLAG_CRUNCHED;
936 #ifdef FEATURE_STATISTICS
937             if (c->flags & CF_COUNT_AS_REJECT)
938             {
939                csp->flags |= CSP_FLAG_REJECTED;
940             }
941 #endif /* def FEATURE_STATISTICS */
942
943             return TRUE;
944          }
945       }
946    }
947
948    return FALSE;
949 }
950
951
952 /*********************************************************************
953  *
954  * Function    :  build_request_line
955  *
956  * Description :  Builds the HTTP request line.
957  *
958  *                If a HTTP forwarder is used it expects the whole URL,
959  *                web servers only get the path.
960  *
961  * Parameters  :
962  *          1  :  csp = Current client state (buffers, headers, etc...)
963  *          2  :  fwd = The forwarding spec used for the request
964  *                XXX: Should use http->fwd instead.
965  *          3  :  request_line = The old request line which will be replaced.
966  *
967  * Returns     :  Nothing. Terminates in case of memory problems.
968  *
969  *********************************************************************/
970 static void build_request_line(struct client_state *csp, const struct forward_spec *fwd, char **request_line)
971 {
972    struct http_request *http = csp->http;
973
974    /*
975     * Downgrade http version from 1.1 to 1.0
976     * if +downgrade action applies.
977     */
978    if ((csp->action->flags & ACTION_DOWNGRADE)
979      && (!strcmpic(http->ver, "HTTP/1.1")))
980    {
981       freez(http->ver);
982       http->ver = strdup_or_die("HTTP/1.0");
983    }
984
985    /*
986     * Rebuild the request line.
987     */
988    freez(*request_line);
989    *request_line = strdup(http->gpc);
990    string_append(request_line, " ");
991
992    if (fwd->forward_host && fwd->type != FORWARD_WEBSERVER)
993    {
994       string_append(request_line, http->url);
995    }
996    else
997    {
998       string_append(request_line, http->path);
999    }
1000    string_append(request_line, " ");
1001    string_append(request_line, http->ver);
1002
1003    if (*request_line == NULL)
1004    {
1005       log_error(LOG_LEVEL_FATAL, "Out of memory writing HTTP command");
1006    }
1007    log_error(LOG_LEVEL_HEADER, "New HTTP Request-Line: %s", *request_line);
1008 }
1009
1010
1011 /*********************************************************************
1012  *
1013  * Function    :  change_request_destination
1014  *
1015  * Description :  Parse a (rewritten) request line and regenerate
1016  *                the http request data.
1017  *
1018  * Parameters  :
1019  *          1  :  csp = Current client state (buffers, headers, etc...)
1020  *
1021  * Returns     :  Forwards the parse_http_request() return code.
1022  *                Terminates in case of memory problems.
1023  *
1024  *********************************************************************/
1025 static jb_err change_request_destination(struct client_state *csp)
1026 {
1027    struct http_request *http = csp->http;
1028    jb_err err;
1029
1030    log_error(LOG_LEVEL_REDIRECTS, "Rewrite detected: %s",
1031       csp->headers->first->str);
1032    free_http_request(http);
1033    err = parse_http_request(csp->headers->first->str, http);
1034    if (JB_ERR_OK != err)
1035    {
1036       log_error(LOG_LEVEL_ERROR, "Couldn't parse rewritten request: %s.",
1037          jb_err_to_string(err));
1038    }
1039
1040    return err;
1041 }
1042
1043
1044 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1045 /*********************************************************************
1046  *
1047  * Function    :  server_response_is_complete
1048  *
1049  * Description :  Determines whether we should stop reading
1050  *                from the server socket.
1051  *
1052  * Parameters  :
1053  *          1  :  csp = Current client state (buffers, headers, etc...)
1054  *          2  :  content_length = Length of content received so far.
1055  *
1056  * Returns     :  TRUE if the response is complete,
1057  *                FALSE otherwise.
1058  *
1059  *********************************************************************/
1060 static int server_response_is_complete(struct client_state *csp,
1061    unsigned long long content_length)
1062 {
1063    int content_length_known = !!(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET);
1064
1065    if (!strcmpic(csp->http->gpc, "HEAD"))
1066    {
1067       /*
1068        * "HEAD" implies no body, we are thus expecting
1069        * no content. XXX: incomplete "list" of methods?
1070        */
1071       csp->expected_content_length = 0;
1072       content_length_known = TRUE;
1073       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1074    }
1075
1076    if (csp->http->status == 204 || csp->http->status == 304)
1077    {
1078       /*
1079        * Expect no body. XXX: incomplete "list" of status codes?
1080        */
1081       csp->expected_content_length = 0;
1082       content_length_known = TRUE;
1083       csp->flags |= CSP_FLAG_SERVER_CONTENT_LENGTH_SET;
1084    }
1085
1086    return (content_length_known && ((0 == csp->expected_content_length)
1087             || (csp->expected_content_length <= content_length)));
1088 }
1089
1090
1091 #ifdef FEATURE_CONNECTION_SHARING
1092 /*********************************************************************
1093  *
1094  * Function    :  wait_for_alive_connections
1095  *
1096  * Description :  Waits for alive connections to timeout.
1097  *
1098  * Parameters  :  N/A
1099  *
1100  * Returns     :  N/A
1101  *
1102  *********************************************************************/
1103 static void wait_for_alive_connections(void)
1104 {
1105    int connections_alive = close_unusable_connections();
1106
1107    while (0 < connections_alive)
1108    {
1109       log_error(LOG_LEVEL_CONNECT,
1110          "Waiting for %d connections to timeout.",
1111          connections_alive);
1112       sleep(60);
1113       connections_alive = close_unusable_connections();
1114    }
1115
1116    log_error(LOG_LEVEL_CONNECT, "No connections to wait for left.");
1117
1118 }
1119 #endif /* def FEATURE_CONNECTION_SHARING */
1120
1121
1122 /*********************************************************************
1123  *
1124  * Function    :  save_connection_destination
1125  *
1126  * Description :  Remembers a connection for reuse later on.
1127  *
1128  * Parameters  :
1129  *          1  :  sfd  = Open socket to remember.
1130  *          2  :  http = The destination for the connection.
1131  *          3  :  fwd  = The forwarder settings used.
1132  *          4  :  server_connection  = storage.
1133  *
1134  * Returns     : void
1135  *
1136  *********************************************************************/
1137 void save_connection_destination(jb_socket sfd,
1138                                  const struct http_request *http,
1139                                  const struct forward_spec *fwd,
1140                                  struct reusable_connection *server_connection)
1141 {
1142    assert(sfd != JB_INVALID_SOCKET);
1143    assert(NULL != http->host);
1144
1145    server_connection->sfd = sfd;
1146    server_connection->host = strdup_or_die(http->host);
1147    server_connection->port = http->port;
1148
1149    assert(NULL != fwd);
1150    assert(server_connection->gateway_host == NULL);
1151    assert(server_connection->gateway_port == 0);
1152    assert(server_connection->forwarder_type == 0);
1153    assert(server_connection->forward_host == NULL);
1154    assert(server_connection->forward_port == 0);
1155
1156    server_connection->forwarder_type = fwd->type;
1157    if (NULL != fwd->gateway_host)
1158    {
1159       server_connection->gateway_host = strdup_or_die(fwd->gateway_host);
1160    }
1161    else
1162    {
1163       server_connection->gateway_host = NULL;
1164    }
1165    server_connection->gateway_port = fwd->gateway_port;
1166
1167    if (NULL != fwd->forward_host)
1168    {
1169       server_connection->forward_host = strdup_or_die(fwd->forward_host);
1170    }
1171    else
1172    {
1173       server_connection->forward_host = NULL;
1174    }
1175    server_connection->forward_port = fwd->forward_port;
1176 }
1177
1178
1179 /*********************************************************************
1180  *
1181  * Function    : verify_request_length
1182  *
1183  * Description : Checks if we already got the whole client requests
1184  *               and sets CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ if
1185  *               we do.
1186  *
1187  *               Data that doesn't belong to the current request is
1188  *               either thrown away to let the client retry on a clean
1189  *               socket, or stashed to be dealt with after the current
1190  *               request is served.
1191  *
1192  * Parameters  :
1193  *          1  :  csp = Current client state (buffers, headers, etc...)
1194  *
1195  * Returns     :  void
1196  *
1197  *********************************************************************/
1198 static void verify_request_length(struct client_state *csp)
1199 {
1200    unsigned long long buffered_request_bytes =
1201       (unsigned long long)(csp->client_iob->eod - csp->client_iob->cur);
1202
1203    if ((csp->expected_client_content_length != 0)
1204       && (buffered_request_bytes != 0))
1205    {
1206       if (csp->expected_client_content_length >= buffered_request_bytes)
1207       {
1208          csp->expected_client_content_length -= buffered_request_bytes;
1209          log_error(LOG_LEVEL_CONNECT, "Reduced expected bytes to %llu "
1210             "to account for the %llu ones we already got.",
1211             csp->expected_client_content_length, buffered_request_bytes);
1212       }
1213       else
1214       {
1215          assert(csp->client_iob->eod > csp->client_iob->cur + csp->expected_client_content_length);
1216          csp->client_iob->eod = csp->client_iob->cur + csp->expected_client_content_length;
1217          log_error(LOG_LEVEL_CONNECT, "Reducing expected bytes to 0. "
1218             "Marking the server socket tainted after throwing %llu bytes away.",
1219             buffered_request_bytes - csp->expected_client_content_length);
1220          csp->expected_client_content_length = 0;
1221          csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1222       }
1223
1224       if (csp->expected_client_content_length == 0)
1225       {
1226          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1227       }
1228    }
1229
1230    if (!(csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ)
1231       && ((csp->client_iob->cur < csp->client_iob->eod)
1232          || (csp->expected_client_content_length != 0)))
1233    {
1234       if (strcmpic(csp->http->gpc, "GET")
1235          && strcmpic(csp->http->gpc, "HEAD")
1236          && strcmpic(csp->http->gpc, "TRACE")
1237          && strcmpic(csp->http->gpc, "OPTIONS")
1238          && strcmpic(csp->http->gpc, "DELETE"))
1239       {
1240          /* XXX: this is an incomplete hack */
1241          csp->flags &= ~CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1242          log_error(LOG_LEVEL_CONNECT, "There better be a request body.");
1243       }
1244       else
1245       {
1246          csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1247
1248          if ((csp->config->feature_flags & RUNTIME_FEATURE_TOLERATE_PIPELINING) == 0)
1249          {
1250             csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1251             log_error(LOG_LEVEL_CONNECT,
1252                "Possible pipeline attempt detected. The connection will not "
1253                "be kept alive and we will only serve the first request.");
1254             /* Nuke the pipelined requests from orbit, just to be sure. */
1255             clear_iob(csp->client_iob);
1256          }
1257          else
1258          {
1259             /*
1260              * Keep the pipelined data around for now, we'll deal with
1261              * it once we're done serving the current request.
1262              */
1263             csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
1264             assert(csp->client_iob->eod >= csp->client_iob->cur);
1265             log_error(LOG_LEVEL_CONNECT, "Complete client request followed by "
1266                "%d bytes of pipelined data received.",
1267                (int)(csp->client_iob->eod - csp->client_iob->cur));
1268          }
1269       }
1270    }
1271    else
1272    {
1273       csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
1274       log_error(LOG_LEVEL_CONNECT, "Complete client request received.");
1275    }
1276 }
1277 #endif /* FEATURE_CONNECTION_KEEP_ALIVE */
1278
1279
1280 /*********************************************************************
1281  *
1282  * Function    :  mark_server_socket_tainted
1283  *
1284  * Description :  Makes sure we don't reuse a server socket
1285  *                (if we didn't read everything the server sent
1286  *                us reusing the socket would lead to garbage).
1287  *
1288  * Parameters  :
1289  *          1  :  csp = Current client state (buffers, headers, etc...)
1290  *
1291  * Returns     :  void.
1292  *
1293  *********************************************************************/
1294 static void mark_server_socket_tainted(struct client_state *csp)
1295 {
1296    /*
1297     * For consistency we always mark the server socket
1298     * tainted, however, to reduce the log noise we only
1299     * emit a log message if the server socket could have
1300     * actually been reused.
1301     */
1302    if ((csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE)
1303       && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED))
1304    {
1305       log_error(LOG_LEVEL_CONNECT,
1306          "Marking the server socket %d tainted.",
1307          csp->server_connection.sfd);
1308    }
1309    csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1310 }
1311
1312 /*********************************************************************
1313  *
1314  * Function    :  get_request_line
1315  *
1316  * Description : Read the client request line.
1317  *
1318  * Parameters  :
1319  *          1  :  csp = Current client state (buffers, headers, etc...)
1320  *
1321  * Returns     :  Pointer to request line or NULL in case of errors.
1322  *
1323  *********************************************************************/
1324 static char *get_request_line(struct client_state *csp)
1325 {
1326    char buf[BUFFER_SIZE];
1327    char *request_line = NULL;
1328    int len;
1329
1330    memset(buf, 0, sizeof(buf));
1331
1332    if ((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) != 0)
1333    {
1334       /*
1335        * If there are multiple pipelined requests waiting,
1336        * the flag will be set again once the next request
1337        * has been parsed.
1338        */
1339       csp->flags &= ~CSP_FLAG_PIPELINED_REQUEST_WAITING;
1340
1341       request_line = get_header(csp->client_iob);
1342       if ((NULL != request_line) && ('\0' != *request_line))
1343       {
1344          return request_line;
1345       }
1346       else
1347       {
1348          log_error(LOG_LEVEL_CONNECT, "No complete request line "
1349             "received yet. Continuing reading from %d.", csp->cfd);
1350       }
1351    }
1352
1353    do
1354    {
1355       if (
1356 #ifdef FUZZ
1357           0 == (csp->flags & CSP_FLAG_FUZZED_INPUT) &&
1358 #endif
1359           !data_is_available(csp->cfd, csp->config->socket_timeout)
1360           )
1361       {
1362          if (socket_is_still_alive(csp->cfd))
1363          {
1364             log_error(LOG_LEVEL_CONNECT,
1365                "No request line on socket %d received in time. Timeout: %d.",
1366                csp->cfd, csp->config->socket_timeout);
1367             write_socket_delayed(csp->cfd, CLIENT_CONNECTION_TIMEOUT_RESPONSE,
1368                strlen(CLIENT_CONNECTION_TIMEOUT_RESPONSE),
1369                get_write_delay(csp));
1370          }
1371          else
1372          {
1373             log_error(LOG_LEVEL_CONNECT,
1374                "The client side of the connection on socket %d got "
1375                "closed without sending a complete request line.", csp->cfd);
1376          }
1377          return NULL;
1378       }
1379
1380       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1381
1382       if (len <= 0) return NULL;
1383
1384       /*
1385        * If there is no memory left for buffering the
1386        * request, there is nothing we can do but hang up
1387        */
1388       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1389       {
1390          return NULL;
1391       }
1392
1393       request_line = get_header(csp->client_iob);
1394
1395    } while ((NULL != request_line) && ('\0' == *request_line));
1396
1397    return request_line;
1398
1399 }
1400
1401 enum chunk_status
1402 {
1403    CHUNK_STATUS_MISSING_DATA,
1404    CHUNK_STATUS_BODY_COMPLETE,
1405    CHUNK_STATUS_PARSE_ERROR
1406 };
1407
1408
1409 /*********************************************************************
1410  *
1411  * Function    :  chunked_body_is_complete
1412  *
1413  * Description :  Figures out whether or not a chunked body is complete.
1414  *
1415  *                Currently it always starts at the beginning of the
1416  *                buffer which is somewhat wasteful and prevents Privoxy
1417  *                from starting to forward the correctly parsed chunks
1418  *                as soon as theoretically possible.
1419  *
1420  *                Should be modified to work with a common buffer,
1421  *                and allow the caller to skip already parsed chunks.
1422  *
1423  *                This would allow the function to be used for unbuffered
1424  *                response bodies as well.
1425  *
1426  * Parameters  :
1427  *          1  :  iob = Buffer with the body to check.
1428  *          2  :  length = Length of complete body
1429  *
1430  * Returns     :  Enum with the result of the check.
1431  *
1432  *********************************************************************/
1433 static enum chunk_status chunked_body_is_complete(struct iob *iob, size_t *length)
1434 {
1435    unsigned int chunksize;
1436    char *p = iob->cur;
1437
1438    do
1439    {
1440       /*
1441        * We need at least a single digit, followed by "\r\n",
1442        * followed by an unknown amount of data, followed by "\r\n".
1443        */
1444       if (p + 5 > iob->eod)
1445       {
1446          return CHUNK_STATUS_MISSING_DATA;
1447       }
1448       if (sscanf(p, "%x", &chunksize) != 1)
1449       {
1450          return CHUNK_STATUS_PARSE_ERROR;
1451       }
1452
1453       /*
1454        * We want at least a single digit, followed by "\r\n",
1455        * followed by the specified amount of data, followed by "\r\n".
1456        */
1457       if (p + chunksize + 5 > iob->eod)
1458       {
1459          return CHUNK_STATUS_MISSING_DATA;
1460       }
1461
1462       /* Skip chunk-size. */
1463       p = strstr(p, "\r\n");
1464       if (NULL == p)
1465       {
1466          return CHUNK_STATUS_PARSE_ERROR;
1467       }
1468       /* Move beyond the chunkdata. */
1469       p += 2 + chunksize;
1470
1471       /* There should be another "\r\n" to skip */
1472       if (memcmp(p, "\r\n", 2))
1473       {
1474          return CHUNK_STATUS_PARSE_ERROR;
1475       }
1476       p += 2;
1477    } while (chunksize > 0U);
1478
1479    *length = (size_t)(p - iob->cur);
1480    assert(*length <= (size_t)(iob->eod - iob->cur));
1481    assert(p <= iob->eod);
1482
1483    return CHUNK_STATUS_BODY_COMPLETE;
1484
1485 }
1486
1487
1488 /*********************************************************************
1489  *
1490  * Function    : receive_chunked_client_request_body
1491  *
1492  * Description : Read the chunk-encoded client request body.
1493  *               Failures are dealt with.
1494  *
1495  * Parameters  :
1496  *          1  :  csp = Current client state (buffers, headers, etc...)
1497  *
1498  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1499  *
1500  *********************************************************************/
1501 static jb_err receive_chunked_client_request_body(struct client_state *csp)
1502 {
1503    size_t body_length;
1504    enum chunk_status status;
1505
1506    while (CHUNK_STATUS_MISSING_DATA ==
1507       (status = chunked_body_is_complete(csp->client_iob, &body_length)))
1508    {
1509       char buf[BUFFER_SIZE];
1510       int len;
1511
1512       if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1513       {
1514          log_error(LOG_LEVEL_ERROR,
1515             "Timeout while waiting for the client body.");
1516          break;
1517       }
1518       len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1519       if (len <= 0)
1520       {
1521          log_error(LOG_LEVEL_ERROR, "Read the client body failed: %E");
1522          break;
1523       }
1524       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1525       {
1526          break;
1527       }
1528    }
1529    if (status != CHUNK_STATUS_BODY_COMPLETE)
1530    {
1531       write_socket_delayed(csp->cfd, CLIENT_BODY_PARSE_ERROR_RESPONSE,
1532          strlen(CLIENT_BODY_PARSE_ERROR_RESPONSE), get_write_delay(csp));
1533       log_error(LOG_LEVEL_CLF,
1534          "%s - - [%T] \"Failed reading chunked client body\" 400 0", csp->ip_addr_str);
1535       return JB_ERR_PARSE;
1536    }
1537    log_error(LOG_LEVEL_CONNECT,
1538       "Chunked client body completely read. Length: %d", body_length);
1539    csp->expected_client_content_length = body_length;
1540
1541    return JB_ERR_OK;
1542
1543 }
1544
1545
1546 #ifdef FUZZ
1547 /*********************************************************************
1548  *
1549  * Function    :  fuzz_chunked_transfer_encoding
1550  *
1551  * Description :  Treat the fuzzed input as chunked transfer encoding
1552  *                to check and dechunk.
1553  *
1554  * Parameters  :
1555  *          1  :  csp      = Used to store the data.
1556  *          2  :  fuzz_input_file = File to read the input from.
1557  *
1558  * Returns     : Result of dechunking
1559  *
1560  *********************************************************************/
1561 extern int fuzz_chunked_transfer_encoding(struct client_state *csp, char *fuzz_input_file)
1562 {
1563    size_t length;
1564    size_t size = (size_t)(csp->iob->eod - csp->iob->cur);
1565    enum chunk_status status;
1566
1567    status = chunked_body_is_complete(csp->iob, &length);
1568    if (CHUNK_STATUS_BODY_COMPLETE != status)
1569    {
1570       log_error(LOG_LEVEL_INFO, "Chunked body is incomplete or invalid");
1571    }
1572
1573    return (JB_ERR_OK == remove_chunked_transfer_coding(csp->iob->cur, &size));
1574
1575 }
1576
1577
1578 /*********************************************************************
1579  *
1580  * Function    : fuzz_client_request
1581  *
1582  * Description : Try to get a client request from the fuzzed input.
1583  *
1584  * Parameters  :
1585  *          1  :  csp = Current client state (buffers, headers, etc...)
1586  *          2  :  fuzz_input_file = File to read the input from.
1587  *
1588  * Returns     :  Result of fuzzing.
1589  *
1590  *********************************************************************/
1591 extern int fuzz_client_request(struct client_state *csp, char *fuzz_input_file)
1592 {
1593    jb_err err;
1594
1595    csp->cfd = 0;
1596    csp->ip_addr_str = "fuzzer";
1597
1598    if (strcmp(fuzz_input_file, "-") != 0)
1599    {
1600       log_error(LOG_LEVEL_FATAL,
1601          "Fuzzed client requests can currenty only be read from stdin (-).");
1602    }
1603    err = receive_client_request(csp);
1604    if (err != JB_ERR_OK)
1605    {
1606       return 1;
1607    }
1608    err = parse_client_request(csp);
1609    if (err != JB_ERR_OK)
1610    {
1611       return 1;
1612    }
1613
1614    return 0;
1615
1616 }
1617 #endif  /* def FUZZ */
1618
1619
1620 #ifdef FEATURE_FORCE_LOAD
1621 /*********************************************************************
1622  *
1623  * Function    :  force_required
1624  *
1625  * Description : Checks a request line to see if it contains
1626  *               the FORCE_PREFIX. If it does, it is removed
1627  *               unless enforcing requests has beend disabled.
1628  *
1629  * Parameters  :
1630  *          1  :  request_line = HTTP request line
1631  *
1632  * Returns     :  TRUE if force is required, FALSE otherwise.
1633  *
1634  *********************************************************************/
1635 static int force_required(const struct client_state *csp, char *request_line)
1636 {
1637    char *p;
1638
1639    p = strstr(request_line, "http://");
1640    if (p != NULL)
1641    {
1642       /* Skip protocol */
1643       p += strlen("http://");
1644    }
1645    else
1646    {
1647       /* Intercepted request usually don't specify the protocol. */
1648       p = request_line;
1649    }
1650
1651    /* Go to the beginning of the path */
1652    p = strstr(p, "/");
1653    if (p == NULL)
1654    {
1655       /*
1656        * If the path is missing the request line is invalid and we
1657        * are done here. The client-visible rejection happens later on.
1658        */
1659       return 0;
1660    }
1661
1662    if (0 == strncmpic(p, FORCE_PREFIX, strlen(FORCE_PREFIX) - 1))
1663    {
1664       if (!(csp->config->feature_flags & RUNTIME_FEATURE_ENFORCE_BLOCKS))
1665       {
1666          /* XXX: Should clean more carefully */
1667          strclean(request_line, FORCE_PREFIX);
1668          log_error(LOG_LEVEL_FORCE,
1669             "Enforcing request: \"%s\".", request_line);
1670
1671          return 1;
1672       }
1673       log_error(LOG_LEVEL_FORCE,
1674          "Ignored force prefix in request: \"%s\".", request_line);
1675    }
1676
1677    return 0;
1678
1679 }
1680 #endif /* def FEATURE_FORCE_LOAD */
1681
1682
1683 /*********************************************************************
1684  *
1685  * Function    :  receive_client_request
1686  *
1687  * Description : Read the client's request (more precisely the
1688  *               client headers) and answer it if necessary.
1689  *
1690  * Parameters  :
1691  *          1  :  csp = Current client state (buffers, headers, etc...)
1692  *
1693  * Returns     :  JB_ERR_OK, JB_ERR_PARSE or JB_ERR_MEMORY
1694  *
1695  *********************************************************************/
1696 static jb_err receive_client_request(struct client_state *csp)
1697 {
1698    char buf[BUFFER_SIZE];
1699    char *p;
1700    char *req = NULL;
1701    struct http_request *http;
1702    int len;
1703    jb_err err;
1704
1705    /* Temporary copy of the client's headers before they get enlisted in csp->headers */
1706    struct list header_list;
1707    struct list *headers = &header_list;
1708
1709    /* We don't care if the arriving data is a valid HTTP request or not. */
1710    csp->requests_received_total++;
1711
1712    http = csp->http;
1713
1714    memset(buf, 0, sizeof(buf));
1715
1716    req = get_request_line(csp);
1717    if (req == NULL)
1718    {
1719       mark_server_socket_tainted(csp);
1720       return JB_ERR_PARSE;
1721    }
1722    assert(*req != '\0');
1723
1724    if (client_protocol_is_unsupported(csp, req))
1725    {
1726       return JB_ERR_PARSE;
1727    }
1728
1729 #ifdef FEATURE_FORCE_LOAD
1730    if (force_required(csp, req))
1731    {
1732       csp->flags |= CSP_FLAG_FORCED;
1733    }
1734 #endif /* def FEATURE_FORCE_LOAD */
1735
1736    err = parse_http_request(req, http);
1737    freez(req);
1738    if (JB_ERR_OK != err)
1739    {
1740       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER),
1741          get_write_delay(csp));
1742       /* XXX: Use correct size */
1743       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
1744       log_error(LOG_LEVEL_ERROR,
1745          "Couldn't parse request line received from %s: %s",
1746          csp->ip_addr_str, jb_err_to_string(err));
1747
1748       free_http_request(http);
1749       return JB_ERR_PARSE;
1750    }
1751
1752    /* grab the rest of the client's headers */
1753    init_list(headers);
1754    for (;;)
1755    {
1756       p = get_header(csp->client_iob);
1757
1758       if (p == NULL)
1759       {
1760          /* There are no additional headers to read. */
1761          break;
1762       }
1763
1764       if (*p == '\0')
1765       {
1766          /*
1767           * We didn't receive a complete header
1768           * line yet, get the rest of it.
1769           */
1770          if (!data_is_available(csp->cfd, csp->config->socket_timeout))
1771          {
1772             log_error(LOG_LEVEL_ERROR,
1773                "Stopped grabbing the client headers.");
1774             destroy_list(headers);
1775             return JB_ERR_PARSE;
1776          }
1777
1778          len = read_socket(csp->cfd, buf, sizeof(buf) - 1);
1779          if (len <= 0)
1780          {
1781             log_error(LOG_LEVEL_ERROR, "read from client failed: %E");
1782             destroy_list(headers);
1783             return JB_ERR_PARSE;
1784          }
1785
1786          if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
1787          {
1788             /*
1789              * If there is no memory left for buffering the
1790              * request, there is nothing we can do but hang up
1791              */
1792             destroy_list(headers);
1793             return JB_ERR_MEMORY;
1794          }
1795       }
1796       else
1797       {
1798          if (!strncmpic(p, "Transfer-Encoding:", 18))
1799          {
1800             /*
1801              * XXX: should be called through sed()
1802              *      but currently can't.
1803              */
1804             client_transfer_encoding(csp, &p);
1805          }
1806          /*
1807           * We were able to read a complete
1808           * header and can finally enlist it.
1809           */
1810          enlist(headers, p);
1811          freez(p);
1812       }
1813    }
1814
1815    if (http->host == NULL)
1816    {
1817       /*
1818        * If we still don't know the request destination,
1819        * the request is invalid or the client uses
1820        * Privoxy without its knowledge.
1821        */
1822       if (JB_ERR_OK != get_request_destination_elsewhere(csp, headers))
1823       {
1824          /*
1825           * Our attempts to get the request destination
1826           * elsewhere failed or Privoxy is configured
1827           * to only accept proxy requests.
1828           *
1829           * An error response has already been send
1830           * and we're done here.
1831           */
1832          return JB_ERR_PARSE;
1833       }
1834    }
1835
1836 #ifdef FEATURE_CLIENT_TAGS
1837    /* XXX: If the headers were enlisted sooner, passing csp would do. */
1838    set_client_address(csp, headers);
1839    get_tag_list_for_client(csp->client_tags, csp->client_address);
1840 #endif
1841
1842    /*
1843     * Determine the actions for this URL
1844     */
1845 #ifdef FEATURE_TOGGLE
1846    if (!(csp->flags & CSP_FLAG_TOGGLED_ON))
1847    {
1848       /* Most compatible set of actions (i.e. none) */
1849       init_current_action(csp->action);
1850    }
1851    else
1852 #endif /* ndef FEATURE_TOGGLE */
1853    {
1854       get_url_actions(csp, http);
1855    }
1856
1857    enlist(csp->headers, http->cmd);
1858
1859    /* Append the previously read headers */
1860    err = list_append_list_unique(csp->headers, headers);
1861    destroy_list(headers);
1862
1863    return err;
1864
1865 }
1866
1867
1868 /*********************************************************************
1869  *
1870  * Function    : parse_client_request
1871  *
1872  * Description : Parses the client's request and decides what to do
1873  *               with it.
1874  *
1875  *               Note that since we're not using select() we could get
1876  *               blocked here if a client connected, then didn't say
1877  *               anything!
1878  *
1879  * Parameters  :
1880  *          1  :  csp = Current client state (buffers, headers, etc...)
1881  *
1882  * Returns     :  JB_ERR_OK or JB_ERR_PARSE
1883  *
1884  *********************************************************************/
1885 static jb_err parse_client_request(struct client_state *csp)
1886 {
1887    struct http_request *http = csp->http;
1888    jb_err err;
1889
1890 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
1891    if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
1892     && (!strcmpic(csp->http->ver, "HTTP/1.1"))
1893     && (csp->http->ssl == 0))
1894    {
1895       /* Assume persistence until further notice */
1896       csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
1897    }
1898
1899    if (csp->http->ssl == 0)
1900    {
1901       /*
1902        * This whole block belongs to chat() but currently
1903        * has to be executed before sed().
1904        */
1905       if (csp->flags & CSP_FLAG_CHUNKED_CLIENT_BODY)
1906       {
1907          if (receive_chunked_client_request_body(csp) != JB_ERR_OK)
1908          {
1909             return JB_ERR_PARSE;
1910          }
1911       }
1912       else
1913       {
1914          csp->expected_client_content_length = get_expected_content_length(csp->headers);
1915       }
1916       verify_request_length(csp);
1917    }
1918    else
1919    {
1920       csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
1921    }
1922 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
1923
1924    err = sed(csp, FILTER_CLIENT_HEADERS);
1925    if (JB_ERR_OK != err)
1926    {
1927       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
1928          csp->ip_addr_str);
1929       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
1930          csp->ip_addr_str, csp->http->cmd);
1931       write_socket_delayed(csp->cfd, CHEADER, strlen(CHEADER), get_write_delay(csp));
1932       return JB_ERR_PARSE;
1933    }
1934    csp->flags |= CSP_FLAG_CLIENT_HEADER_PARSING_DONE;
1935
1936    /* Check request line for rewrites. */
1937    if ((NULL == csp->headers->first->str)
1938       || (strcmp(http->cmd, csp->headers->first->str) &&
1939          (JB_ERR_OK != change_request_destination(csp))))
1940    {
1941       /*
1942        * A header filter broke the request line - bail out.
1943        */
1944       write_socket_delayed(csp->cfd, MESSED_UP_REQUEST_RESPONSE,
1945          strlen(MESSED_UP_REQUEST_RESPONSE), get_write_delay(csp));
1946       /* XXX: Use correct size */
1947       log_error(LOG_LEVEL_CLF,
1948          "%s - - [%T] \"Invalid request generated\" 500 0", csp->ip_addr_str);
1949       log_error(LOG_LEVEL_ERROR,
1950          "Invalid request line after applying header filters.");
1951       free_http_request(http);
1952
1953       return JB_ERR_PARSE;
1954    }
1955
1956    if (client_has_unsupported_expectations(csp))
1957    {
1958       return JB_ERR_PARSE;
1959    }
1960
1961    return JB_ERR_OK;
1962
1963 }
1964
1965
1966 /*********************************************************************
1967  *
1968  * Function    : send_http_request
1969  *
1970  * Description : Sends the HTTP headers from the client request
1971  *               and all the body data that has already been received.
1972  *
1973  * Parameters  :
1974  *          1  :  csp = Current client state (buffers, headers, etc...)
1975  *
1976  * Returns     :  0 on success, anything else is an error.
1977  *
1978  *********************************************************************/
1979 static int send_http_request(struct client_state *csp)
1980 {
1981    char *hdr;
1982    int write_failure;
1983
1984    hdr = list_to_text(csp->headers);
1985    if (hdr == NULL)
1986    {
1987       /* FIXME Should handle error properly */
1988       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header");
1989    }
1990    list_remove_all(csp->headers);
1991
1992    /*
1993     * Write the client's (modified) header to the server
1994     * (along with anything else that may be in the buffer)
1995     */
1996    write_failure = 0 != write_socket(csp->server_connection.sfd, hdr, strlen(hdr));
1997    freez(hdr);
1998
1999    if (write_failure)
2000    {
2001       log_error(LOG_LEVEL_CONNECT, "Failed sending request headers to: %s: %E",
2002          csp->http->hostport);
2003    }
2004    else if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2005       && (flush_iob(csp->server_connection.sfd, csp->client_iob, 0) < 0))
2006    {
2007       write_failure = 1;
2008       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2009          csp->http->hostport);
2010    }
2011
2012    return write_failure;
2013
2014 }
2015
2016
2017 #ifdef FEATURE_HTTPS_INSPECTION
2018 /*********************************************************************
2019  *
2020  * Function    : receive_and_send_encrypted_post_data
2021  *
2022  * Description : Reads remaining POST data from the client and sends
2023  *               it to the server.
2024  *
2025  * Parameters  :
2026  *          1  :  csp = Current client state (buffers, headers, etc...)
2027  *
2028  * Returns     :  0 on success, anything else is an error.
2029  *
2030  *********************************************************************/
2031 static jb_err receive_and_send_encrypted_post_data(struct client_state *csp)
2032 {
2033    unsigned char buf[BUFFER_SIZE];
2034    int len;
2035
2036    while (is_ssl_pending(&(csp->mbedtls_client_attr.ssl)))
2037    {
2038       len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl), buf, sizeof(buf));
2039       if (len == -1)
2040       {
2041          return 1;
2042       }
2043       if (len == 0)
2044       {
2045          /* XXX: Does this actually happen? */
2046          break;
2047       }
2048       log_error(LOG_LEVEL_HEADER, "Forwarding %d bytes of encrypted POST data",
2049          len);
2050       len = ssl_send_data(&(csp->mbedtls_server_attr.ssl), buf, (size_t)len);
2051       if (len == -1)
2052       {
2053          return 1;
2054       }
2055       if (csp->expected_client_content_length != 0)
2056       {
2057          if (csp->expected_client_content_length >= len)
2058          {
2059             csp->expected_client_content_length -= (unsigned)len;
2060          }
2061       }
2062    }
2063
2064    log_error(LOG_LEVEL_HEADER, "Done forwarding encrypted POST data");
2065
2066    return 0;
2067
2068 }
2069
2070
2071 /*********************************************************************
2072  *
2073  * Function    : send_https_request
2074  *
2075  * Description : Sends the HTTP headers from the client request
2076  *               and all the body data that has already been received.
2077  *
2078  * Parameters  :
2079  *          1  :  csp = Current client state (buffers, headers, etc...)
2080  *
2081  * Returns     :  0 on success, anything else is an error.
2082  *
2083  *********************************************************************/
2084 static int send_https_request(struct client_state *csp)
2085 {
2086    char *hdr;
2087    int ret;
2088    long flushed = 0;
2089
2090    hdr = list_to_text(csp->https_headers);
2091    if (hdr == NULL)
2092    {
2093       /* FIXME Should handle error properly */
2094       log_error(LOG_LEVEL_FATAL, "Out of memory parsing client header");
2095    }
2096    list_remove_all(csp->https_headers);
2097
2098    /*
2099     * Write the client's (modified) header to the server
2100     * (along with anything else that may be in the buffer)
2101     */
2102    ret = ssl_send_data(&(csp->mbedtls_server_attr.ssl),
2103       (const unsigned char *)hdr, strlen(hdr));
2104    freez(hdr);
2105
2106    if (ret < 0)
2107    {
2108       log_error(LOG_LEVEL_CONNECT,
2109          "Failed sending encrypted request headers to: %s: %E",
2110          csp->http->hostport);
2111       mark_server_socket_tainted(csp);
2112       close_client_and_server_ssl_connections(csp);
2113       return 1;
2114    }
2115
2116    if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) == 0)
2117       && ((flushed = ssl_flush_socket(&(csp->mbedtls_server_attr.ssl),
2118             csp->client_iob)) < 0))
2119    {
2120       log_error(LOG_LEVEL_CONNECT, "Failed sending request body to: %s: %E",
2121          csp->http->hostport);
2122       return 1;
2123    }
2124    if (flushed != 0)
2125    {
2126       if (csp->expected_client_content_length != 0)
2127       {
2128          if (csp->expected_client_content_length < flushed)
2129          {
2130             log_error(LOG_LEVEL_ERROR,
2131                "Flushed %d bytes of request body while only expecting %llu",
2132                flushed, csp->expected_client_content_length);
2133             csp->expected_client_content_length = 0;
2134          }
2135          else
2136          {
2137             log_error(LOG_LEVEL_CONNECT,
2138                "Flushed %d bytes of request body while expecting %llu",
2139                flushed, csp->expected_client_content_length);
2140             csp->expected_client_content_length -= (unsigned)flushed;
2141             if (receive_and_send_encrypted_post_data(csp))
2142             {
2143                return 1;
2144             }
2145          }
2146       }
2147       else
2148       {
2149          log_error(LOG_LEVEL_CONNECT,
2150             "Flushed %d bytes of request body", flushed);
2151       }
2152    }
2153
2154    log_error(LOG_LEVEL_CONNECT, "Encrypted request sent");
2155
2156    return 0;
2157
2158 }
2159
2160
2161 /*********************************************************************
2162  *
2163  * Function    :  receive_encrypted_request
2164  *
2165  * Description :  Receives an encrypted request.
2166  *
2167  * Parameters  :
2168  *          1  :  csp = Current client state (buffers, headers, etc...)
2169  *
2170  * Returns     :  JB_ERR_OK on success,
2171  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2172  *
2173  *********************************************************************/
2174 static jb_err receive_encrypted_request(struct client_state *csp)
2175 {
2176    char buf[BUFFER_SIZE];
2177    int len;
2178    char *p;
2179
2180    do
2181    {
2182       log_error(LOG_LEVEL_HEADER, "Reading encrypted headers");
2183       if (!data_is_available(csp->cfd, (int)csp->config->keep_alive_timeout))
2184       {
2185          log_error(LOG_LEVEL_CONNECT,
2186             "Socket %d timed out while waiting for client headers", csp->cfd);
2187          return JB_ERR_PARSE;
2188       }
2189       len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl),
2190          (unsigned char *)buf, sizeof(buf));
2191       if (len == -1)
2192       {
2193          return JB_ERR_PARSE;
2194       }
2195       if (add_to_iob(csp->client_iob, csp->config->buffer_limit, buf, len))
2196       {
2197          return JB_ERR_MEMORY;
2198       }
2199       p = strstr(csp->client_iob->cur, "\r\n\r\n");
2200    } while (p == NULL);
2201
2202    log_error(LOG_LEVEL_HEADER, "Encrypted headers received completely");
2203
2204    return JB_ERR_OK;
2205 }
2206
2207
2208 /*********************************************************************
2209  *
2210  * Function    :  process_encrypted_request
2211  *
2212  * Description :  Receives and parses an encrypted request.
2213  *
2214  * Parameters  :
2215  *          1  :  csp = Current client state (buffers, headers, etc...)
2216  *
2217  * Returns     :  JB_ERR_OK on success,
2218  *                JB_ERR_PARSE or JB_ERR_MEMORY otherwise
2219  *
2220  *********************************************************************/
2221 static jb_err process_encrypted_request(struct client_state *csp)
2222 {
2223    char *p;
2224    char *request_line;
2225    jb_err err;
2226    /* Temporary copy of the client's headers before they get enlisted in csp->https_headers */
2227    struct list header_list;
2228    struct list *headers = &header_list;
2229
2230    err = receive_encrypted_request(csp);
2231    if (err != JB_ERR_OK)
2232    {
2233       /* XXX: Also used for JB_ERR_MEMORY */
2234       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2235          (const unsigned char *)CHEADER, strlen(CHEADER));
2236       return err;
2237    }
2238
2239    /* We don't need get_request_line() because the whole HTTP head is buffered. */
2240    request_line = get_header(csp->client_iob);
2241    if (request_line == NULL)
2242    {
2243       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2244          (const unsigned char *)CHEADER, strlen(CHEADER));
2245       return JB_ERR_PARSE;
2246    }
2247    assert(*request_line != '\0');
2248
2249    if (client_protocol_is_unsupported(csp, request_line))
2250    {
2251       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2252          (const unsigned char *)CHEADER, strlen(CHEADER));
2253       return JB_ERR_PARSE;
2254    }
2255
2256 #ifdef FEATURE_FORCE_LOAD
2257    if (force_required(csp, request_line))
2258    {
2259       csp->flags |= CSP_FLAG_FORCED;
2260    }
2261 #endif /* def FEATURE_FORCE_LOAD */
2262
2263    free_http_request(csp->http);
2264
2265    err = parse_http_request(request_line, csp->http);
2266    /* XXX: Restore ssl setting. This is ugly */
2267    csp->http->client_ssl = 1;
2268    csp->http->server_ssl = 1;
2269
2270    freez(request_line);
2271    if (JB_ERR_OK != err)
2272    {
2273       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2274          (const unsigned char *)CHEADER, strlen(CHEADER));
2275       /* XXX: Use correct size */
2276       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"Invalid request\" 400 0", csp->ip_addr_str);
2277       log_error(LOG_LEVEL_ERROR,
2278          "Couldn't parse request line received from %s: %s",
2279          csp->ip_addr_str, jb_err_to_string(err));
2280
2281       free_http_request(csp->http);
2282       return JB_ERR_PARSE;
2283    }
2284
2285    /* Parse the rest of the client's headers. */
2286    init_list(headers);
2287    for (;;)
2288    {
2289       p = get_header(csp->client_iob);
2290
2291       if (p == NULL)
2292       {
2293          /* There are no additional headers to read. */
2294          break;
2295       }
2296       enlist(headers, p);
2297       freez(p);
2298    }
2299
2300    if (JB_ERR_OK != get_destination_from_https_headers(headers, csp->http))
2301    {
2302       /*
2303        * Our attempts to get the request destination
2304        * elsewhere failed.
2305        */
2306       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2307          (const unsigned char *)CHEADER, strlen(CHEADER));
2308       return JB_ERR_PARSE;
2309    }
2310
2311 #ifndef FEATURE_EXTENDED_HOST_PATTERNS
2312    /* Split the domain we just got for pattern matching */
2313    init_domain_components(csp->http);
2314 #endif
2315
2316 #ifdef FEATURE_TOGGLE
2317    if ((csp->flags & CSP_FLAG_TOGGLED_ON) != 0)
2318 #endif
2319    {
2320       /* Determine the actions for this URL */
2321       get_url_actions(csp, csp->http);
2322    }
2323
2324    enlist(csp->https_headers, csp->http->cmd);
2325
2326    /* Append the previously read headers */
2327    err = list_append_list_unique(csp->https_headers, headers);
2328    destroy_list(headers);
2329    if (JB_ERR_OK != err)
2330    {
2331       /* XXX: Send error message */
2332       return err;
2333    }
2334
2335    /* XXX: Work around crash */
2336    csp->error_message = NULL;
2337
2338    /* XXX: Why do this here? */
2339    csp->http->ssl = 1;
2340
2341    err = sed_https(csp);
2342    if (JB_ERR_OK != err)
2343    {
2344       ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2345          (const unsigned char *)CHEADER, strlen(CHEADER));
2346       log_error(LOG_LEVEL_ERROR, "Failed to parse client request from %s.",
2347          csp->ip_addr_str);
2348       log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 400 0",
2349          csp->ip_addr_str, csp->http->cmd);
2350       return JB_ERR_PARSE;
2351    }
2352
2353    log_error(LOG_LEVEL_HEADER, "Encrypted request processed");
2354    log_applied_actions(csp->action);
2355
2356    return err;
2357
2358 }
2359 #endif
2360
2361
2362 /*********************************************************************
2363  *
2364  * Function    :  handle_established_connection
2365  *
2366  * Description :  Shuffle data between client and server once the
2367  *                connection has been established.
2368  *
2369  * Parameters  :
2370  *          1  :  csp = Current client state (buffers, headers, etc...)
2371  *
2372  * Returns     :  Nothing.
2373  *
2374  *********************************************************************/
2375 static void handle_established_connection(struct client_state *csp)
2376 {
2377    char *hdr;
2378    char *p;
2379    int n;
2380 #ifdef HAVE_POLL
2381    struct pollfd poll_fds[2];
2382 #else
2383    fd_set rfds;
2384    jb_socket maxfd;
2385    struct timeval timeout;
2386 #endif
2387    int server_body;
2388    int ms_iis5_hack = 0;
2389    unsigned long long byte_count = 0;
2390    struct http_request *http;
2391    long len = 0; /* for buffer sizes (and negative error codes) */
2392    int buffer_and_filter_content = 0;
2393    unsigned int write_delay;
2394 #ifdef FEATURE_HTTPS_INSPECTION
2395    int ret = 0;
2396    int use_ssl_tunnel = 0;
2397    csp->dont_verify_certificate = 0;
2398
2399    /*
2400     * Preset flags informing if SSL connections with server or client
2401     * are opened or closed
2402     */
2403    csp->ssl_with_server_is_opened = 0;
2404    csp->ssl_with_client_is_opened = 0;
2405
2406    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION))
2407    {
2408       /* Pass encrypted content without filtering. */
2409       use_ssl_tunnel = 1;
2410    }
2411 #endif
2412
2413    /* Skeleton for HTTP response, if we should intercept the request */
2414    struct http_response *rsp;
2415 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2416    int watch_client_socket;
2417 #endif
2418
2419    csp->receive_buffer_size = csp->config->receive_buffer_size;
2420    csp->receive_buffer = zalloc(csp->receive_buffer_size + 1);
2421    if (csp->receive_buffer == NULL)
2422    {
2423       log_error(LOG_LEVEL_ERROR,
2424          "Out of memory. Failed to allocate the receive buffer.");
2425       rsp = cgi_error_memory();
2426       send_crunch_response(csp, rsp);
2427       return;
2428    }
2429
2430    http = csp->http;
2431
2432 #ifndef HAVE_POLL
2433    maxfd = (csp->cfd > csp->server_connection.sfd) ?
2434       csp->cfd : csp->server_connection.sfd;
2435 #endif
2436
2437    /* pass data between the client and server
2438     * until one or the other shuts down the connection.
2439     */
2440
2441    server_body = 0;
2442
2443 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2444    watch_client_socket = 0 == (csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING);
2445 #endif
2446    write_delay = get_write_delay(csp);
2447
2448    for (;;)
2449    {
2450 #ifndef HAVE_POLL
2451 #ifdef __OS2__
2452       /*
2453        * FD_ZERO here seems to point to an errant macro which crashes.
2454        * So do this by hand for now...
2455        */
2456       memset(&rfds,0x00,sizeof(fd_set));
2457 #else
2458       FD_ZERO(&rfds);
2459 #endif
2460 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2461       if (!watch_client_socket)
2462       {
2463          maxfd = csp->server_connection.sfd;
2464       }
2465       else
2466 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2467       {
2468          FD_SET(csp->cfd, &rfds);
2469       }
2470
2471       FD_SET(csp->server_connection.sfd, &rfds);
2472 #endif /* ndef HAVE_POLL */
2473
2474 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2475       if ((csp->flags & CSP_FLAG_CHUNKED)
2476          && !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
2477          && ((csp->iob->eod - csp->iob->cur) >= 5)
2478          && !memcmp(csp->iob->eod-5, "0\r\n\r\n", 5))
2479       {
2480          /*
2481           * XXX: This check should be obsolete now,
2482           *      but let's wait a while to be sure.
2483           */
2484          log_error(LOG_LEVEL_CONNECT,
2485             "Looks like we got the last chunk together with "
2486             "the server headers but didn't detect it earlier. "
2487             "We better stop reading.");
2488          byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
2489          csp->expected_content_length = byte_count;
2490          csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2491       }
2492       if (server_body && server_response_is_complete(csp, byte_count))
2493       {
2494          if (csp->expected_content_length == byte_count)
2495          {
2496             log_error(LOG_LEVEL_CONNECT,
2497                "Done reading from server. Content length: %llu as expected. "
2498                "Bytes most recently read: %d.",
2499                byte_count, len);
2500          }
2501          else
2502          {
2503             log_error(LOG_LEVEL_CONNECT,
2504                "Done reading from server. Expected content length: %llu. "
2505                "Actual content length: %llu. Bytes most recently read: %d.",
2506                csp->expected_content_length, byte_count, len);
2507          }
2508          len = 0;
2509          /*
2510           * XXX: Should not jump around, handle_established_connection()
2511           * is complicated enough already.
2512           */
2513          goto reading_done;
2514       }
2515 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
2516
2517 #ifdef FEATURE_HTTPS_INSPECTION
2518       /*
2519        * Test if some data from client or destination server are pending
2520        * on TLS/SSL. We must work with them preferably. TLS/SSL data can
2521        * be pending because of maximal fragment size.
2522        */
2523       int read_ssl_server = 0;
2524       int read_ssl_client = 0;
2525
2526       if (client_use_ssl(csp))
2527       {
2528          read_ssl_client = is_ssl_pending(&(csp->mbedtls_client_attr.ssl)) != 0;
2529       }
2530
2531       if (server_use_ssl(csp))
2532       {
2533          read_ssl_server = is_ssl_pending(&(csp->mbedtls_server_attr.ssl)) != 0;
2534       }
2535
2536       if (!read_ssl_server && !read_ssl_client)
2537 #endif
2538       {
2539 #ifdef HAVE_POLL
2540          poll_fds[0].fd = csp->cfd;
2541 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2542          if (!watch_client_socket)
2543          {
2544             /*
2545              * Ignore incoming data, but still watch out
2546              * for disconnects etc. These flags are always
2547              * implied anyway but explicitly setting them
2548              * doesn't hurt.
2549              */
2550             poll_fds[0].events = POLLERR|POLLHUP;
2551          }
2552          else
2553 #endif
2554          {
2555             poll_fds[0].events = POLLIN;
2556          }
2557          poll_fds[1].fd = csp->server_connection.sfd;
2558          poll_fds[1].events = POLLIN;
2559          n = poll(poll_fds, 2, csp->config->socket_timeout * 1000);
2560 #else
2561          timeout.tv_sec = csp->config->socket_timeout;
2562          timeout.tv_usec = 0;
2563          n = select((int)maxfd + 1, &rfds, NULL, NULL, &timeout);
2564 #endif /* def HAVE_POLL */
2565
2566          /*server or client not responding in timeout */
2567          if (n == 0)
2568          {
2569             log_error(LOG_LEVEL_CONNECT, "Socket timeout %d reached: %s",
2570                csp->config->socket_timeout, http->url);
2571             if ((byte_count == 0) && (http->ssl == 0))
2572             {
2573                send_crunch_response(csp, error_response(csp, "connection-timeout"));
2574             }
2575             mark_server_socket_tainted(csp);
2576 #ifdef FEATURE_HTTPS_INSPECTION
2577             close_client_and_server_ssl_connections(csp);
2578 #endif
2579             return;
2580          }
2581          else if (n < 0)
2582          {
2583 #ifdef HAVE_POLL
2584             log_error(LOG_LEVEL_ERROR, "poll() failed!: %E");
2585 #else
2586             log_error(LOG_LEVEL_ERROR, "select() failed!: %E");
2587 #endif
2588             mark_server_socket_tainted(csp);
2589 #ifdef FEATURE_HTTPS_INSPECTION
2590             close_client_and_server_ssl_connections(csp);
2591 #endif
2592             return;
2593          }
2594       }
2595 #ifdef FEATURE_HTTPS_INSPECTION
2596       else
2597       {
2598          /* set FD if some data are pending on TLS/SSL connections */
2599 #ifndef HAVE_POLL
2600          FD_ZERO(&rfds);
2601 #endif
2602          if (read_ssl_client)
2603          {
2604 #ifdef HAVE_POLL
2605             poll_fds[0].fd = csp->cfd;
2606             poll_fds[0].events = POLLIN;
2607 #else
2608             FD_SET(csp->cfd, &rfds);
2609 #endif
2610             n++;
2611          }
2612
2613          if (read_ssl_server)
2614          {
2615 #ifdef HAVE_POLL
2616             poll_fds[1].fd = csp->server_connection.sfd;
2617             poll_fds[1].events = POLLIN;
2618 #else
2619             FD_SET(csp->server_connection.sfd, &rfds);
2620 #endif
2621             n++;
2622          }
2623       }
2624 #endif
2625       /*
2626        * This is the body of the browser's request,
2627        * just read and write it.
2628        *
2629        * Receives data from browser and sends it to server
2630        *
2631        * XXX: Make sure the client doesn't use pipelining
2632        * behind Privoxy's back.
2633        */
2634 #ifdef HAVE_POLL
2635       if ((poll_fds[0].revents & (POLLERR|POLLHUP|POLLNVAL)) != 0)
2636       {
2637          log_error(LOG_LEVEL_CONNECT,
2638             "The client socket %d has become unusable while "
2639             "the server socket %d is still open.",
2640             csp->cfd, csp->server_connection.sfd);
2641          mark_server_socket_tainted(csp);
2642          break;
2643       }
2644
2645       if (poll_fds[0].revents != 0)
2646 #else
2647       if (FD_ISSET(csp->cfd, &rfds))
2648 #endif /* def HAVE_POLL*/
2649       {
2650          int max_bytes_to_read = (int)csp->receive_buffer_size;
2651
2652 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2653          if ((csp->flags & CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ))
2654          {
2655             if (data_is_available(csp->cfd, 0))
2656             {
2657                /*
2658                 * If the next request is already waiting, we have
2659                 * to stop select()ing the client socket. Otherwise
2660                 * we would always return right away and get nothing
2661                 * else done.
2662                 */
2663                watch_client_socket = 0;
2664                log_error(LOG_LEVEL_CONNECT,
2665                   "Stop watching client socket %d. "
2666                   "There's already another request waiting.",
2667                   csp->cfd);
2668                continue;
2669             }
2670             /*
2671              * If the client socket is set, but there's no data
2672              * available on the socket, the client went fishing
2673              * and continuing talking to the server makes no sense.
2674              */
2675             log_error(LOG_LEVEL_CONNECT,
2676                "The client closed socket %d while "
2677                "the server socket %d is still open.",
2678                csp->cfd, csp->server_connection.sfd);
2679             mark_server_socket_tainted(csp);
2680             break;
2681          }
2682          if (csp->expected_client_content_length != 0)
2683          {
2684             if (csp->expected_client_content_length < csp->receive_buffer_size)
2685             {
2686                max_bytes_to_read = (int)csp->expected_client_content_length;
2687             }
2688             log_error(LOG_LEVEL_CONNECT,
2689                "Waiting for up to %d bytes from the client.",
2690                max_bytes_to_read);
2691          }
2692          assert(max_bytes_to_read <= csp->receive_buffer_size);
2693 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2694
2695 #ifdef FEATURE_HTTPS_INSPECTION
2696          /*
2697           * Reading data from standard or secured connection (HTTP/HTTPS)
2698           */
2699          if (client_use_ssl(csp))
2700          {
2701             /*
2702              * Receiving HTTP request from client over TLS/SSL and sending
2703              * it to server over TLS/SSL.
2704              */
2705             len = ssl_recv_data(&(csp->mbedtls_client_attr.ssl),
2706                (unsigned char *)csp->receive_buffer, (size_t)max_bytes_to_read);
2707
2708             if (len <= 0)
2709             {
2710                mark_server_socket_tainted(csp);
2711                break;
2712             }
2713
2714             ret = ssl_send_data(&(csp->mbedtls_server_attr.ssl),
2715                (const unsigned char *)csp->receive_buffer, (size_t)len);
2716
2717             if (ret < 0)
2718             {
2719                log_error(LOG_LEVEL_ERROR,
2720                   "Send request over TLS/SSL to: %s failed", http->host);
2721                mark_server_socket_tainted(csp);
2722                close_client_and_server_ssl_connections(csp);
2723                return;
2724             }
2725          }
2726          else
2727 #endif /* def FEATURE_HTTPS_INSPECTION */
2728          {
2729             len = read_socket(csp->cfd, csp->receive_buffer, max_bytes_to_read);
2730
2731             if (len <= 0)
2732             {
2733                /* XXX: not sure if this is necessary. */
2734                mark_server_socket_tainted(csp);
2735                break; /* "game over, man" */
2736             }
2737
2738 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2739             if (csp->expected_client_content_length != 0)
2740             {
2741                assert(len <= max_bytes_to_read);
2742                csp->expected_client_content_length -= (unsigned)len;
2743                log_error(LOG_LEVEL_CONNECT,
2744                   "Expected client content length set to %llu "
2745                   "after reading %d bytes.",
2746                   csp->expected_client_content_length, len);
2747                if (csp->expected_client_content_length == 0)
2748                {
2749                   log_error(LOG_LEVEL_CONNECT,
2750                      "Done reading from the client.");
2751                   csp->flags |= CSP_FLAG_CLIENT_REQUEST_COMPLETELY_READ;
2752                }
2753             }
2754 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2755
2756             if (write_socket(csp->server_connection.sfd, csp->receive_buffer, (size_t)len))
2757             {
2758                log_error(LOG_LEVEL_ERROR, "write to: %s failed: %E", http->host);
2759                mark_server_socket_tainted(csp);
2760 #ifdef FEATURE_HTTPS_INSPECTION
2761                close_client_and_server_ssl_connections(csp);
2762 #endif
2763                return;
2764             }
2765          }
2766          continue;
2767       }
2768
2769       /*
2770        * The server wants to talk. It could be the header or the body.
2771        * If `hdr' is null, then it's the header otherwise it's the body.
2772        * FIXME: Does `hdr' really mean `host'? No.
2773        */
2774 #ifdef HAVE_POLL
2775       if (poll_fds[1].revents != 0)
2776 #else
2777       if (FD_ISSET(csp->server_connection.sfd, &rfds))
2778 #endif /* HAVE_POLL */
2779       {
2780 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2781          /*
2782           * If we are buffering content, we don't want to eat up to
2783           * buffer-limit bytes if the client no longer cares about them.
2784           * If we aren't buffering, however, a dead client socket will be
2785           * noticed pretty much right away anyway, so we can reduce the
2786           * overhead by skipping the check.
2787           */
2788          if (buffer_and_filter_content && !socket_is_still_alive(csp->cfd))
2789          {
2790 #ifdef _WIN32
2791             log_error(LOG_LEVEL_CONNECT,
2792                "The server still wants to talk, but the client may already have hung up on us.");
2793 #else
2794             log_error(LOG_LEVEL_CONNECT,
2795                "The server still wants to talk, but the client hung up on us.");
2796             mark_server_socket_tainted(csp);
2797 #ifdef FEATURE_HTTPS_INSPECTION
2798             close_client_and_server_ssl_connections(csp);
2799 #endif
2800             return;
2801 #endif /* def _WIN32 */
2802          }
2803 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
2804
2805 #ifdef FEATURE_HTTPS_INSPECTION
2806          /*
2807           * Reading data from standard or secured connection (HTTP/HTTPS)
2808           */
2809          if (server_use_ssl(csp))
2810          {
2811             len = ssl_recv_data(&(csp->mbedtls_server_attr.ssl),
2812                (unsigned char *)csp->receive_buffer, csp->receive_buffer_size);
2813          }
2814          else
2815 #endif
2816          {
2817             len = read_socket(csp->server_connection.sfd, csp->receive_buffer,
2818                (int)csp->receive_buffer_size);
2819          }
2820
2821          if (len < 0)
2822          {
2823             log_error(LOG_LEVEL_ERROR, "read from: %s failed: %E", http->host);
2824
2825             if ((http->ssl && (csp->fwd == NULL))
2826 #ifdef FEATURE_HTTPS_INSPECTION
2827                && use_ssl_tunnel
2828 #endif
2829                 )
2830             {
2831                /*
2832                 * Just hang up. We already confirmed the client's CONNECT
2833                 * request with status code 200 and unencrypted content is
2834                 * no longer welcome.
2835                 */
2836                log_error(LOG_LEVEL_ERROR,
2837                   "CONNECT already confirmed. Unable to tell the client about the problem.");
2838                return;
2839             }
2840             else if (byte_count)
2841             {
2842                /*
2843                 * Just hang up. We already transmitted the original headers
2844                 * and parts of the original content and therefore missed the
2845                 * chance to send an error message (without risking data corruption).
2846                 *
2847                 * XXX: we could retry with a fancy range request here.
2848                 */
2849                log_error(LOG_LEVEL_ERROR, "Already forwarded the original headers. "
2850                   "Unable to tell the client about the problem.");
2851                mark_server_socket_tainted(csp);
2852 #ifdef FEATURE_HTTPS_INSPECTION
2853                close_client_and_server_ssl_connections(csp);
2854 #endif
2855                return;
2856             }
2857             /*
2858              * XXX: Consider handling the cases above the same.
2859              */
2860             mark_server_socket_tainted(csp);
2861             len = 0;
2862          }
2863
2864 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
2865          if (csp->flags & CSP_FLAG_CHUNKED)
2866          {
2867             if ((len >= 5) && !memcmp(csp->receive_buffer+len-5, "0\r\n\r\n", 5))
2868             {
2869                /* XXX: this is a temporary hack */
2870                log_error(LOG_LEVEL_CONNECT,
2871                   "Looks like we reached the end of the last chunk. "
2872                   "We better stop reading.");
2873                csp->expected_content_length = byte_count + (unsigned long long)len;
2874                csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
2875             }
2876          }
2877          reading_done:
2878 #endif  /* FEATURE_CONNECTION_KEEP_ALIVE */
2879
2880          /*
2881           * This is guaranteed by allocating with zalloc_or_die()
2882           * and never (intentionally) writing to the last byte.
2883           *
2884           * csp->receive_buffer_size is the size of the part of the
2885           * buffer we intentionally write to, but we actually
2886           * allocated csp->receive_buffer_size+1 bytes so the assertion
2887           * stays within the allocated range.
2888           */
2889          assert(csp->receive_buffer[csp->receive_buffer_size] == '\0');
2890
2891          /*
2892           * Add a trailing zero to let be able to use string operations.
2893           * XXX: do we still need this with filter_popups gone?
2894           */
2895          assert(len <= csp->receive_buffer_size);
2896          csp->receive_buffer[len] = '\0';
2897
2898          /*
2899           * Normally, this would indicate that we've read
2900           * as much as the server has sent us and we can
2901           * close the client connection.  However, Microsoft
2902           * in its wisdom has released IIS/5 with a bug that
2903           * prevents it from sending the trailing \r\n in
2904           * a 302 redirect header (and possibly other headers).
2905           * To work around this if we've haven't parsed
2906           * a full header we'll append a trailing \r\n
2907           * and see if this now generates a valid one.
2908           *
2909           * This hack shouldn't have any impacts.  If we've
2910           * already transmitted the header or if this is a
2911           * SSL connection, then we won't bother with this
2912           * hack.  So we only work on partially received
2913           * headers.  If we append a \r\n and this still
2914           * doesn't generate a valid header, then we won't
2915           * transmit anything to the client.
2916           */
2917          if (len == 0)
2918          {
2919
2920             if (server_body || (http->ssl
2921 #ifdef FEATURE_HTTPS_INSPECTION
2922                   && use_ssl_tunnel
2923 #endif
2924                ))
2925             {
2926                /*
2927                 * If we have been buffering up the document,
2928                 * now is the time to apply content modification
2929                 * and send the result to the client.
2930                 */
2931                if (buffer_and_filter_content)
2932                {
2933                   p = execute_content_filters(csp);
2934                   /*
2935                    * If content filtering fails, use the original
2936                    * buffer and length.
2937                    * (see p != NULL ? p : csp->iob->cur below)
2938                    */
2939                   if (NULL == p)
2940                   {
2941                      csp->content_length = (size_t)(csp->iob->eod - csp->iob->cur);
2942                   }
2943 #ifdef FEATURE_COMPRESSION
2944                   else if ((csp->flags & CSP_FLAG_CLIENT_SUPPORTS_DEFLATE)
2945                      && (csp->content_length > LOWER_LENGTH_LIMIT_FOR_COMPRESSION))
2946                   {
2947                      char *compressed_content = compress_buffer(p,
2948                         (size_t *)&csp->content_length, csp->config->compression_level);
2949                      if (compressed_content != NULL)
2950                      {
2951                         freez(p);
2952                         p = compressed_content;
2953                         csp->flags |= CSP_FLAG_BUFFERED_CONTENT_DEFLATED;
2954                      }
2955                   }
2956 #endif
2957
2958                   if (JB_ERR_OK != update_server_headers(csp))
2959                   {
2960                      log_error(LOG_LEVEL_FATAL,
2961                         "Failed to update server headers. after filtering.");
2962                   }
2963
2964                   hdr = list_to_text(csp->headers);
2965                   if (hdr == NULL)
2966                   {
2967                      /* FIXME Should handle error properly */
2968                      log_error(LOG_LEVEL_FATAL, "Out of memory parsing server header");
2969                   }
2970
2971 #ifdef FEATURE_HTTPS_INSPECTION
2972                   /*
2973                    * Sending data with standard or secured connection (HTTP/HTTPS)
2974                    */
2975                   if (client_use_ssl(csp))
2976                   {
2977                      if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2978                             (const unsigned char *)hdr, strlen(hdr)) < 0)
2979                         || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
2980                               (const unsigned char *) ((p != NULL) ? p : csp->iob->cur),
2981                               csp->content_length) < 0))
2982                      {
2983                         log_error(LOG_LEVEL_ERROR, "write modified content to "
2984                            "client over TLS/SSL failed");
2985                         freez(hdr);
2986                         freez(p);
2987                         mark_server_socket_tainted(csp);
2988                         close_client_and_server_ssl_connections(csp);
2989                         return;
2990                      }
2991                   }
2992                   else
2993 #endif /* def FEATURE_HTTPS_INSPECTION */
2994                   {
2995                      if (write_socket_delayed(csp->cfd, hdr, strlen(hdr), write_delay)
2996                       || write_socket_delayed(csp->cfd, ((p != NULL) ? p : csp->iob->cur),
2997                          (size_t)csp->content_length, write_delay))
2998                      {
2999                         log_error(LOG_LEVEL_ERROR, "write modified content to client failed: %E");
3000                         freez(hdr);
3001                         freez(p);
3002                         mark_server_socket_tainted(csp);
3003 #ifdef FEATURE_HTTPS_INSPECTION
3004                         close_client_and_server_ssl_connections(csp);
3005 #endif
3006                         return;
3007                      }
3008                   }
3009
3010                   freez(hdr);
3011                   freez(p);
3012                }
3013
3014                break; /* "game over, man" */
3015             }
3016
3017             /*
3018              * This is NOT the body, so
3019              * Let's pretend the server just sent us a blank line.
3020              */
3021             snprintf(csp->receive_buffer, csp->receive_buffer_size, "\r\n");
3022             len = (int)strlen(csp->receive_buffer);
3023
3024             /*
3025              * Now, let the normal header parsing algorithm below do its
3026              * job.  If it fails, we'll exit instead of continuing.
3027              */
3028
3029             ms_iis5_hack = 1;
3030          }
3031
3032          /*
3033           * If we're in the body of the server document, just write it to
3034           * the client, unless we need to buffer the body for later
3035           * content-filtering.
3036           */
3037          if (server_body || (http->ssl
3038 #ifdef FEATURE_HTTPS_INSPECTION
3039                && use_ssl_tunnel
3040 #endif
3041             ))
3042          {
3043             if (buffer_and_filter_content)
3044             {
3045                /*
3046                 * If there is no memory left for buffering the content, or the buffer limit
3047                 * has been reached, switch to non-filtering mode, i.e. make & write the
3048                 * header, flush the iob and buf, and get out of the way.
3049                 */
3050                if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3051                {
3052                   size_t hdrlen;
3053                   long flushed;
3054
3055                   log_error(LOG_LEVEL_INFO,
3056                      "Flushing header and buffers. Stepping back from filtering.");
3057
3058                   hdr = list_to_text(csp->headers);
3059                   if (hdr == NULL)
3060                   {
3061                      /*
3062                       * Memory is too tight to even generate the header.
3063                       * Send our static "Out-of-memory" page.
3064                       */
3065                      log_error(LOG_LEVEL_ERROR, "Out of memory while trying to flush.");
3066                      rsp = cgi_error_memory();
3067                      send_crunch_response(csp, rsp);
3068                      mark_server_socket_tainted(csp);
3069 #ifdef FEATURE_HTTPS_INSPECTION
3070                      close_client_and_server_ssl_connections(csp);
3071 #endif
3072                      return;
3073                   }
3074                   hdrlen = strlen(hdr);
3075
3076 #ifdef FEATURE_HTTPS_INSPECTION
3077                   /*
3078                    * Sending data with standard or secured connection (HTTP/HTTPS)
3079                    */
3080                   if (client_use_ssl(csp))
3081                   {
3082                      if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3083                             (const unsigned char *)hdr, hdrlen) < 0)
3084                         || ((flushed = ssl_flush_socket(&(csp->mbedtls_client_attr.ssl),
3085                                 csp->iob)) < 0)
3086                         || (ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3087                               (const unsigned char *)csp->receive_buffer, (size_t)len) < 0))
3088                      {
3089                         log_error(LOG_LEVEL_CONNECT,
3090                            "Flush header and buffers to client failed");
3091                         freez(hdr);
3092                         mark_server_socket_tainted(csp);
3093                         close_client_and_server_ssl_connections(csp);
3094                         return;
3095                      }
3096                   }
3097                   else
3098 #endif /* def FEATURE_HTTPS_INSPECTION */
3099                   {
3100                      if (write_socket_delayed(csp->cfd, hdr, hdrlen, write_delay)
3101                       || ((flushed = flush_iob(csp->cfd, csp->iob, write_delay)) < 0)
3102                       || write_socket_delayed(csp->cfd, csp->receive_buffer, (size_t)len,
3103                             write_delay))
3104                      {
3105                         log_error(LOG_LEVEL_CONNECT,
3106                            "Flush header and buffers to client failed: %E");
3107                         freez(hdr);
3108                         mark_server_socket_tainted(csp);
3109 #ifdef FEATURE_HTTPS_INSPECTION
3110                         close_client_and_server_ssl_connections(csp);
3111 #endif
3112                         return;
3113                      }
3114                   }
3115
3116                   /*
3117                    * Reset the byte_count to the amount of bytes
3118                    * we just flushed. len will be added a few lines below,
3119                    * hdrlen doesn't matter for LOG_LEVEL_CLF.
3120                    */
3121                   byte_count = (unsigned long long)flushed;
3122                   freez(hdr);
3123                   buffer_and_filter_content = 0;
3124                   server_body = 1;
3125                }
3126             }
3127             else
3128             {
3129 #ifdef FEATURE_HTTPS_INSPECTION
3130                /*
3131                 * Sending data with standard or secured connection (HTTP/HTTPS)
3132                 */
3133                if (client_use_ssl(csp))
3134                {
3135                   ret = ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3136                      (const unsigned char *)csp->receive_buffer, (size_t)len);
3137                   if (ret < 0)
3138                   {
3139                      log_error(LOG_LEVEL_ERROR,
3140                         "Sending data to client failed");
3141                      mark_server_socket_tainted(csp);
3142                      close_client_and_server_ssl_connections(csp);
3143                      return;
3144                   }
3145                }
3146                else
3147 #endif /* def FEATURE_HTTPS_INSPECTION */
3148                {
3149                   if (write_socket_delayed(csp->cfd, csp->receive_buffer,
3150                         (size_t)len, write_delay))
3151                   {
3152                      log_error(LOG_LEVEL_ERROR, "write to client failed: %E");
3153                      mark_server_socket_tainted(csp);
3154 #ifdef FEATURE_HTTPS_INSPECTION
3155                      close_client_and_server_ssl_connections(csp);
3156 #endif
3157                      return;
3158                   }
3159                }
3160             }
3161             byte_count += (unsigned long long)len;
3162             continue;
3163          }
3164          else
3165          {
3166             /*
3167              * We're still looking for the end of the server's header.
3168              * Buffer up the data we just read.  If that fails, there's
3169              * little we can do but send our static out-of-memory page.
3170              */
3171             if (add_to_iob(csp->iob, csp->config->buffer_limit, csp->receive_buffer, len))
3172             {
3173                log_error(LOG_LEVEL_ERROR, "Out of memory while looking for end of server headers.");
3174                rsp = cgi_error_memory();
3175                send_crunch_response(csp, rsp);
3176                mark_server_socket_tainted(csp);
3177 #ifdef FEATURE_HTTPS_INSPECTION
3178                close_client_and_server_ssl_connections(csp);
3179 #endif
3180                return;
3181             }
3182
3183             /* Convert iob into something sed() can digest */
3184             if (JB_ERR_PARSE == get_server_headers(csp))
3185             {
3186                if (ms_iis5_hack)
3187                {
3188                   /*
3189                    * Well, we tried our MS IIS/5 hack and it didn't work.
3190                    * The header is incomplete and there isn't anything
3191                    * we can do about it.
3192                    */
3193                   log_error(LOG_LEVEL_ERROR, "Invalid server headers. "
3194                      "Applying the MS IIS5 hack didn't help.");
3195                   log_error(LOG_LEVEL_CLF,
3196                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3197 #ifdef FEATURE_HTTPS_INSPECTION
3198                   /*
3199                    * Sending data with standard or secured connection (HTTP/HTTPS)
3200                    */
3201                   if (client_use_ssl(csp))
3202                   {
3203                      ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3204                         (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3205                         strlen(INVALID_SERVER_HEADERS_RESPONSE));
3206                   }
3207                   else
3208 #endif /* def FEATURE_HTTPS_INSPECTION */
3209                   {
3210                      write_socket_delayed(csp->cfd,
3211                         INVALID_SERVER_HEADERS_RESPONSE,
3212                         strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3213                   }
3214                   mark_server_socket_tainted(csp);
3215 #ifdef FEATURE_HTTPS_INSPECTION
3216                   close_client_and_server_ssl_connections(csp);
3217 #endif
3218                   return;
3219                }
3220                else
3221                {
3222                   /*
3223                    * Since we have to wait for more from the server before
3224                    * we can parse the headers we just continue here.
3225                    */
3226                   log_error(LOG_LEVEL_CONNECT,
3227                      "Continuing buffering server headers from socket %d. "
3228                      "Bytes most recently read: %d.", csp->cfd, len);
3229                   continue;
3230                }
3231             }
3232             else
3233             {
3234                /*
3235                 * Account for the content bytes we
3236                 * might have gotten with the headers.
3237                 */
3238                assert(csp->iob->eod >= csp->iob->cur);
3239                byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
3240             }
3241
3242             /* Did we actually get anything? */
3243             if (NULL == csp->headers->first)
3244             {
3245                if ((csp->flags & CSP_FLAG_REUSED_CLIENT_CONNECTION))
3246                {
3247                   log_error(LOG_LEVEL_ERROR,
3248                      "No server or forwarder response received on socket %d. "
3249                      "Closing client socket %d without sending data.",
3250                      csp->server_connection.sfd, csp->cfd);
3251                   log_error(LOG_LEVEL_CLF,
3252                      "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3253                }
3254                else
3255                {
3256                   log_error(LOG_LEVEL_ERROR,
3257                      "No server or forwarder response received on socket %d.",
3258                      csp->server_connection.sfd);
3259                   send_crunch_response(csp, error_response(csp, "no-server-data"));
3260                }
3261                free_http_request(http);
3262                mark_server_socket_tainted(csp);
3263 #ifdef FEATURE_HTTPS_INSPECTION
3264                close_client_and_server_ssl_connections(csp);
3265 #endif
3266                return;
3267             }
3268
3269             if (!csp->headers->first->str)
3270             {
3271                log_error(LOG_LEVEL_ERROR, "header search: csp->headers->first->str == NULL, assert will be called");
3272             }
3273             assert(csp->headers->first->str);
3274
3275             if (strncmpic(csp->headers->first->str, "HTTP", 4) &&
3276                 strncmpic(csp->headers->first->str, "ICY", 3))
3277             {
3278                /*
3279                 * It doesn't look like a HTTP (or Shoutcast) response:
3280                 * tell the client and log the problem.
3281                 */
3282                if (strlen(csp->headers->first->str) > 30)
3283                {
3284                   csp->headers->first->str[30] = '\0';
3285                }
3286                log_error(LOG_LEVEL_ERROR,
3287                   "Invalid server or forwarder response. Starts with: %s",
3288                   csp->headers->first->str);
3289                log_error(LOG_LEVEL_CLF,
3290                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3291 #ifdef FEATURE_HTTPS_INSPECTION
3292                /*
3293                 * Sending data with standard or secured connection (HTTP/HTTPS)
3294                 */
3295                if (client_use_ssl(csp))
3296                {
3297                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3298                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3299                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3300                }
3301                else
3302 #endif /* def FEATURE_HTTPS_INSPECTION */
3303                {
3304                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3305                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3306                }
3307                free_http_request(http);
3308                mark_server_socket_tainted(csp);
3309 #ifdef FEATURE_HTTPS_INSPECTION
3310                close_client_and_server_ssl_connections(csp);
3311 #endif
3312                return;
3313             }
3314
3315             /*
3316              * We have now received the entire server header,
3317              * filter it and send the result to the client
3318              */
3319             if (JB_ERR_OK != sed(csp, FILTER_SERVER_HEADERS))
3320             {
3321                log_error(LOG_LEVEL_CLF,
3322                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3323 #ifdef FEATURE_HTTPS_INSPECTION
3324                /*
3325                 * Sending data with standard or secured connection (HTTP/HTTPS)
3326                 */
3327                if (client_use_ssl(csp))
3328                {
3329                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3330                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3331                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3332                }
3333                else
3334 #endif
3335                {
3336                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3337                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3338                }
3339                free_http_request(http);
3340                mark_server_socket_tainted(csp);
3341 #ifdef FEATURE_HTTPS_INSPECTION
3342                close_client_and_server_ssl_connections(csp);
3343 #endif
3344                return;
3345             }
3346             hdr = list_to_text(csp->headers);
3347             if (hdr == NULL)
3348             {
3349                /* FIXME Should handle error properly */
3350                log_error(LOG_LEVEL_FATAL, "Out of memory parsing server header");
3351             }
3352
3353             if ((csp->flags & CSP_FLAG_CHUNKED)
3354                && !(csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
3355                && ((csp->iob->eod - csp->iob->cur) >= 5)
3356                && !memcmp(csp->iob->eod-5, "0\r\n\r\n", 5))
3357             {
3358                log_error(LOG_LEVEL_CONNECT,
3359                   "Looks like we got the last chunk together with "
3360                   "the server headers. We better stop reading.");
3361                byte_count = (unsigned long long)(csp->iob->eod - csp->iob->cur);
3362                csp->expected_content_length = byte_count;
3363                csp->flags |= CSP_FLAG_CONTENT_LENGTH_SET;
3364             }
3365
3366             csp->server_connection.response_received = time(NULL);
3367
3368             if (crunch_response_triggered(csp, crunchers_light))
3369             {
3370                /*
3371                 * One of the tags created by a server-header
3372                 * tagger triggered a crunch. We already
3373                 * delivered the crunch response to the client
3374                 * and are done here after cleaning up.
3375                 */
3376                freez(hdr);
3377                mark_server_socket_tainted(csp);
3378 #ifdef FEATURE_HTTPS_INSPECTION
3379                close_client_and_server_ssl_connections(csp);
3380 #endif
3381                return;
3382             }
3383
3384             /* Buffer and pcrs filter this if appropriate. */
3385             buffer_and_filter_content = content_requires_filtering(csp);
3386
3387             if (!buffer_and_filter_content)
3388             {
3389                /*
3390                 * Write the server's (modified) header to
3391                 * the client (along with anything else that
3392                 * may be in the buffer). Use standard or secured
3393                 * connection.
3394                 */
3395 #ifdef FEATURE_HTTPS_INSPECTION
3396                if (client_use_ssl(csp))
3397                {
3398                   if ((ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3399                           (const unsigned char *)hdr, strlen(hdr)) < 0)
3400                      || (len = ssl_flush_socket(&(csp->mbedtls_client_attr.ssl),
3401                             csp->iob) < 0))
3402                   {
3403                      log_error(LOG_LEVEL_CONNECT, "Write header to client failed");
3404
3405                      /*
3406                       * The write failed, so don't bother mentioning it
3407                       * to the client... it probably can't hear us anyway.
3408                       */
3409                      freez(hdr);
3410                      mark_server_socket_tainted(csp);
3411 #ifdef FEATURE_HTTPS_INSPECTION
3412                      close_client_and_server_ssl_connections(csp);
3413 #endif
3414                      return;
3415                   }
3416                }
3417                else
3418 #endif /* def FEATURE_HTTPS_INSPECTION */
3419                {
3420                   if (write_socket_delayed(csp->cfd, hdr, strlen(hdr), write_delay)
3421                      || ((len = flush_iob(csp->cfd, csp->iob, write_delay)) < 0))
3422                   {
3423                      log_error(LOG_LEVEL_ERROR,
3424                         "write header to client failed");
3425                      /*
3426                       * The write failed, so don't bother mentioning it
3427                       * to the client... it probably can't hear us anyway.
3428                       */
3429                      freez(hdr);
3430                      mark_server_socket_tainted(csp);
3431 #ifdef FEATURE_HTTPS_INSPECTION
3432                      close_client_and_server_ssl_connections(csp);
3433 #endif
3434                      return;
3435                   }
3436                }
3437                                 }
3438
3439             /* we're finished with the server's header */
3440
3441             freez(hdr);
3442             server_body = 1;
3443
3444             /*
3445              * If this was a MS IIS/5 hack then it means the server
3446              * has already closed the connection. Nothing more to read.
3447              * Time to bail.
3448              */
3449             if (ms_iis5_hack)
3450             {
3451                log_error(LOG_LEVEL_ERROR,
3452                   "Closed server connection detected. "
3453                   "Applying the MS IIS5 hack didn't help.");
3454                log_error(LOG_LEVEL_CLF,
3455                   "%s - - [%T] \"%s\" 502 0", csp->ip_addr_str, http->cmd);
3456 #ifdef FEATURE_HTTPS_INSPECTION
3457                /*
3458                 * Sending data with standard or secured connection (HTTP/HTTPS)
3459                 */
3460                if (client_use_ssl(csp))
3461                {
3462                   ssl_send_data(&(csp->mbedtls_client_attr.ssl),
3463                      (const unsigned char *)INVALID_SERVER_HEADERS_RESPONSE,
3464                      strlen(INVALID_SERVER_HEADERS_RESPONSE));
3465                }
3466                else
3467 #endif /* def FEATURE_HTTPS_INSPECTION */
3468                {
3469                   write_socket_delayed(csp->cfd, INVALID_SERVER_HEADERS_RESPONSE,
3470                      strlen(INVALID_SERVER_HEADERS_RESPONSE), write_delay);
3471                }
3472                mark_server_socket_tainted(csp);
3473 #ifdef FEATURE_HTTPS_INSPECTION
3474                close_client_and_server_ssl_connections(csp);
3475 #endif
3476                return;
3477             }
3478          }
3479          continue;
3480       }
3481       mark_server_socket_tainted(csp);
3482 #ifdef FEATURE_HTTPS_INSPECTION
3483       close_client_and_server_ssl_connections(csp);
3484 #endif
3485       return; /* huh? we should never get here */
3486    }
3487 #ifdef FEATURE_HTTPS_INSPECTION
3488    close_client_and_server_ssl_connections(csp);
3489 #endif
3490    if (csp->content_length == 0)
3491    {
3492       /*
3493        * If Privoxy didn't recalculate the Content-Length,
3494        * byte_count is still correct.
3495        */
3496       csp->content_length = byte_count;
3497    }
3498
3499 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3500    if ((csp->flags & CSP_FLAG_CONTENT_LENGTH_SET)
3501       && (csp->expected_content_length != byte_count))
3502    {
3503       log_error(LOG_LEVEL_CONNECT,
3504          "Received %llu bytes while expecting %llu.",
3505          byte_count, csp->expected_content_length);
3506       mark_server_socket_tainted(csp);
3507    }
3508 #endif
3509
3510    log_error(LOG_LEVEL_CLF, "%s - - [%T] \"%s\" 200 %llu",
3511       csp->ip_addr_str, http->ocmd, csp->content_length);
3512
3513    csp->server_connection.timestamp = time(NULL);
3514 }
3515
3516
3517 /*********************************************************************
3518  *
3519  * Function    :  chat
3520  *
3521  * Description :  Once a connection from the client has been accepted,
3522  *                this function is called (via serve()) to handle the
3523  *                main business of the communication.  This function
3524  *                returns after dealing with a single request. It can
3525  *                be called multiple times with the same client socket
3526  *                if the client is keeping the connection alive.
3527  *
3528  *                The decision whether or not a client connection will
3529  *                be kept alive is up to the caller which also must
3530  *                close the client socket when done.
3531  *
3532  *                FIXME: chat is nearly thousand lines long.
3533  *                Ridiculous.
3534  *
3535  * Parameters  :
3536  *          1  :  csp = Current client state (buffers, headers, etc...)
3537  *
3538  * Returns     :  Nothing.
3539  *
3540  *********************************************************************/
3541 static void chat(struct client_state *csp)
3542 {
3543    const struct forward_spec *fwd;
3544    struct http_request *http;
3545    /* Skeleton for HTTP response, if we should intercept the request */
3546    struct http_response *rsp;
3547 #ifdef FEATURE_HTTPS_INSPECTION
3548    int use_ssl_tunnel = 0;
3549 #endif
3550
3551    http = csp->http;
3552
3553    if (receive_client_request(csp) != JB_ERR_OK)
3554    {
3555       return;
3556    }
3557    if (parse_client_request(csp) != JB_ERR_OK)
3558    {
3559       return;
3560    }
3561
3562    /* decide how to route the HTTP request */
3563    fwd = forward_url(csp, http);
3564    if (NULL == fwd)
3565    {
3566       log_error(LOG_LEVEL_FATAL, "gateway spec is NULL!?!?  This can't happen!");
3567       /* Never get here - LOG_LEVEL_FATAL causes program exit */
3568       return;
3569    }
3570
3571 #ifdef FEATURE_HTTPS_INSPECTION
3572    /*
3573     * Setting flags to use old solution with SSL tunnel and to disable
3574     * certificates verification.
3575     */
3576    if (csp->http->ssl && !(csp->action->flags & ACTION_HTTPS_INSPECTION))
3577    {
3578       use_ssl_tunnel = 1;
3579    }
3580
3581    if (http->ssl && csp->action->flags & ACTION_IGNORE_CERTIFICATE_ERRORS)
3582    {
3583       csp->dont_verify_certificate = 1;
3584    }
3585 #endif
3586
3587    /*
3588     * build the http request to send to the server
3589     * we have to do one of the following:
3590     *
3591     * create =    use the original HTTP request to create a new
3592     *             HTTP request that has either the path component
3593     *             without the http://domainspec (w/path) or the
3594     *             full orininal URL (w/url)
3595     *             Note that the path and/or the HTTP version may
3596     *             have been altered by now.
3597     *
3598     * SSL proxy = Open a socket to the host:port of the server
3599     *             and create TLS/SSL connection with server and
3600     *             with client. Then behave like mediator between
3601     *             client and server over TLS/SSL.
3602     *
3603     * SSL proxy = Pass the request unchanged if forwarding a CONNECT
3604     *    with     request to a parent proxy. Note that we'll be sending
3605     * forwarding  the CFAIL message ourselves if connecting to the parent
3606     *             fails, but we won't send a CSUCCEED message if it works,
3607     *             since that would result in a double message (ours and the
3608     *             parent's). After sending the request to the parent, we
3609     *             must parse answer and send it to client. If connection
3610     *             with server is established, we do TLS/SSL proxy. Otherwise
3611     *             we send parent response to client and close connections.
3612     *
3613     * here's the matrix:
3614     *                        SSL
3615     *                    0        1
3616     *                +--------+--------+
3617     *                |        |        |
3618     *             0  | create |   SSL  |
3619     *                | w/path |  proxy |
3620     *  Forwarding    +--------+--------+
3621     *                |        |   SSL  |
3622     *             1  | create |  proxy |
3623     *                | w/url  |+forward|
3624     *                +--------+--------+
3625     *
3626     */
3627
3628 #ifdef FEATURE_HTTPS_INSPECTION
3629    /*
3630     * Presetting SSL client and server flags
3631     */
3632    if (http->ssl && !use_ssl_tunnel)
3633    {
3634       http->client_ssl = 1;
3635       http->server_ssl = 1;
3636    }
3637    else
3638    {
3639       http->client_ssl = 0;
3640       http->server_ssl = 0;
3641    }
3642 #endif
3643
3644    if (http->ssl && connect_port_is_forbidden(csp))
3645    {
3646       const char *acceptable_connect_ports =
3647          csp->action->string[ACTION_STRING_LIMIT_CONNECT];
3648       assert(NULL != acceptable_connect_ports);
3649       log_error(LOG_LEVEL_INFO, "Request from %s marked for blocking. "
3650          "limit-connect{%s} doesn't allow CONNECT requests to %s",
3651          csp->ip_addr_str, acceptable_connect_ports, csp->http->hostport);
3652       csp->action->flags |= ACTION_BLOCK;
3653       http->ssl = 0;
3654 #ifdef FEATURE_HTTPS_INSPECTION
3655       http->client_ssl = 0;
3656       http->server_ssl = 0;
3657 #endif
3658    }
3659
3660
3661    freez(csp->headers->first->str);
3662    build_request_line(csp, fwd, &csp->headers->first->str);
3663
3664    /*
3665     * We have a request. Check if one of the crunchers wants it
3666     * unless the client wants to use TLS/SSL in which case we
3667     * haven't setup the TLS context yet and will send the crunch
3668     * response later.
3669     */
3670    if (
3671 #ifdef FEATURE_HTTPS_INSPECTION
3672        !client_use_ssl(csp) &&
3673 #endif
3674        crunch_response_triggered(csp, crunchers_all))
3675    {
3676       /*
3677        * Yes. The client got the crunch response and we're done here.
3678        */
3679       return;
3680    }
3681
3682    log_applied_actions(csp->action);
3683    log_error(LOG_LEVEL_GPC, "%s%s", http->hostport, http->path);
3684
3685    if (fwd->forward_host)
3686    {
3687       log_error(LOG_LEVEL_CONNECT, "via [%s]:%d to: %s",
3688          fwd->forward_host, fwd->forward_port, http->hostport);
3689    }
3690    else
3691    {
3692       log_error(LOG_LEVEL_CONNECT, "to %s", http->hostport);
3693    }
3694
3695    /* here we connect to the server, gateway, or the forwarder */
3696
3697 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3698    if ((csp->server_connection.sfd != JB_INVALID_SOCKET)
3699       && socket_is_still_alive(csp->server_connection.sfd)
3700       && connection_destination_matches(&csp->server_connection, http, fwd))
3701    {
3702       log_error(LOG_LEVEL_CONNECT,
3703          "Reusing server socket %d connected to %s. Total requests: %u.",
3704          csp->server_connection.sfd, csp->server_connection.host,
3705          csp->server_connection.requests_sent_total);
3706    }
3707    else
3708    {
3709       if (csp->server_connection.sfd != JB_INVALID_SOCKET)
3710       {
3711 #ifdef FEATURE_CONNECTION_SHARING
3712          if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
3713          {
3714             remember_connection(&csp->server_connection);
3715          }
3716          else
3717 #endif /* def FEATURE_CONNECTION_SHARING */
3718          {
3719             log_error(LOG_LEVEL_CONNECT,
3720                "Closing server socket %d connected to %s. Total requests: %u.",
3721                csp->server_connection.sfd, csp->server_connection.host,
3722                csp->server_connection.requests_sent_total);
3723             close_socket(csp->server_connection.sfd);
3724          }
3725          mark_connection_closed(&csp->server_connection);
3726       }
3727 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3728 #ifdef FEATURE_HTTPS_INSPECTION
3729       if (http->ssl && !use_ssl_tunnel)
3730       {
3731          int ret;
3732          /*
3733           * Creating an SSL proxy. If forwarding is disabled, we must send
3734           * CSUCCEED mesage to client. Then TLS/SSL connection with client
3735           * is created.
3736           */
3737
3738          if (fwd->forward_host == NULL)
3739          {
3740             /*
3741              * We're lying to the client as the connection hasn't actually
3742              * been established yet. We don't establish the connection until
3743              * we have seen and parsed the encrypted client headers.
3744              */
3745             if (write_socket_delayed(csp->cfd, CSUCCEED,
3746                   strlen(CSUCCEED), get_write_delay(csp)) != 0)
3747             {
3748                log_error(LOG_LEVEL_ERROR, "Sending SUCCEED to client failed");
3749                return;
3750             }
3751          }
3752
3753          ret = create_client_ssl_connection(csp);
3754          if (ret != 0)
3755          {
3756             log_error(LOG_LEVEL_ERROR,
3757                "Can't open secure connection with client");
3758             close_client_ssl_connection(csp); /* XXX: Is this needed? */
3759             return;
3760          }
3761          if (JB_ERR_OK != process_encrypted_request(csp))
3762          {
3763             log_error(LOG_LEVEL_ERROR, "Failed to parse encrypted request.");
3764             close_client_ssl_connection(csp);
3765             return;
3766          }
3767          /*
3768           * We have an encrypted request. Check if one of the crunchers now
3769           * wants it (for example because the previously invisible path was
3770           * required to match).
3771           */
3772          if (crunch_response_triggered(csp, crunchers_all))
3773          {
3774             /*
3775              * Yes. The client got the crunch response and we're done here.
3776              */
3777             close_client_ssl_connection(csp);
3778             return;
3779          }
3780       }
3781 #endif
3782       /*
3783        * Connecting to destination server
3784        */
3785       csp->server_connection.sfd = forwarded_connect(fwd, http, csp);
3786
3787       if (csp->server_connection.sfd == JB_INVALID_SOCKET)
3788       {
3789          if (fwd->type != SOCKS_NONE)
3790          {
3791             /* Socks error. */
3792             rsp = error_response(csp, "forwarding-failed");
3793          }
3794          else if (errno == EINVAL)
3795          {
3796             rsp = error_response(csp, "no-such-domain");
3797          }
3798          else
3799          {
3800             rsp = error_response(csp, "connect-failed");
3801          }
3802
3803          /* Write the answer to the client */
3804          if (rsp != NULL)
3805          {
3806             send_crunch_response(csp, rsp);
3807          }
3808
3809          /*
3810           * Temporary workaround to prevent already-read client
3811           * bodies from being parsed as new requests. For now we
3812           * err on the safe side and throw all the following
3813           * requests under the bus, even if no client body has been
3814           * buffered. A compliant client will repeat the dropped
3815           * requests on an untainted connection.
3816           *
3817           * The proper fix is to discard the no longer needed
3818           * client body in the buffer (if there is one) and to
3819           * continue parsing the bytes that follow.
3820           */
3821          drain_and_close_socket(csp->cfd);
3822          csp->cfd = JB_INVALID_SOCKET;
3823
3824          return;
3825       }
3826
3827 #ifdef FEATURE_HTTPS_INSPECTION
3828       /*
3829        * Creating TLS/SSL connections with destination server or parent
3830        * proxy. If forwarding is enabled, we must send client request to
3831        * parent proxy and receive, parse and resend parent proxy answer.
3832        */
3833       if (http->ssl && !use_ssl_tunnel)
3834       {
3835          if (fwd->forward_host != NULL)
3836          {
3837             char server_response[BUFFER_SIZE];
3838             int ret = 0;
3839             int len = 0;
3840             char *hdr = list_to_text(csp->headers);
3841             memset(server_response, 0, sizeof(server_response));
3842
3843             if (hdr == NULL)
3844             {
3845                log_error(LOG_LEVEL_FATAL,
3846                   "Out of memory parsing client header");
3847             }
3848             list_remove_all(csp->headers);
3849
3850             /*
3851              * Sending client's CONNECT request to the parent proxy
3852              */
3853             ret = write_socket(csp->server_connection.sfd, hdr, strlen(hdr));
3854
3855             freez(hdr);
3856
3857             if (ret != 0)
3858             {
3859                log_error(LOG_LEVEL_CONNECT,
3860                   "Sending request headers to: %s failed", http->hostport);
3861                mark_server_socket_tainted(csp);
3862                close_client_ssl_connection(csp);
3863                return;
3864             }
3865
3866             /* Waiting for parent proxy server response */
3867             len = read_socket(csp->server_connection.sfd, server_response,
3868                sizeof(server_response)-1);
3869
3870             if (len <= 0)
3871             {
3872                log_error(LOG_LEVEL_ERROR, "No response from parent proxy "
3873                   "server on socket %d.", csp->server_connection.sfd);
3874
3875                rsp = error_response(csp, "no-server-data");
3876                if (rsp)
3877                {
3878                   send_crunch_response(csp, rsp);
3879                }
3880                mark_server_socket_tainted(csp);
3881                close_client_ssl_connection(csp);
3882                return;
3883             }
3884
3885             /*
3886              * Test if connection with destination server was established
3887              * successfully by parent proxy. Then we can send response to
3888              * the client and continue or stop.
3889              */
3890             if (!tunnel_established_successfully(server_response, (unsigned int)len))
3891             {
3892                log_error(LOG_LEVEL_ERROR, "Forwarder hasn't established "
3893                   "connection with destination server.");
3894
3895                write_socket(csp->cfd, server_response, (size_t)len);
3896                mark_server_socket_tainted(csp);
3897                close_client_ssl_connection(csp);
3898                return;
3899             }
3900
3901             /*
3902              * Parent proxy has established connection with destination server.
3903              * Now we must create TLS/SSL connection with parent proxy.
3904              */
3905             ret = create_server_ssl_connection(csp);
3906
3907             /*
3908             * If TLS/SSL connection wasn't created and invalid certificate
3909             * wasn't detected, we can interrupt this function. Otherwise, we
3910             * must inform the client about invalid server certificate.
3911             */
3912             if (ret != 0
3913                && (csp->server_cert_verification_result == SSL_CERT_NOT_VERIFIED
3914                   || csp->server_cert_verification_result == SSL_CERT_VALID))
3915             {
3916                rsp = error_response(csp, "connect-failed");
3917                if (rsp)
3918                {
3919                   send_crunch_response(csp, rsp);
3920                }
3921                return;
3922             }
3923
3924             /*
3925              * TLS/SSL connection with parent proxy is established, we can
3926              * inform client about success.
3927              */
3928             ret = write_socket(csp->cfd, server_response, (size_t)len);
3929             if (ret != 0)
3930             {
3931                log_error(LOG_LEVEL_ERROR,
3932                   "Sending parent proxy response to client failed");
3933                mark_server_socket_tainted(csp);
3934                close_client_ssl_connection(csp);
3935                return;
3936             }
3937          }/* -END- if (fwd->forward_host != NULL) */
3938          else
3939          {
3940             /*
3941              * Parent proxy is not used, we can just create TLS/SSL connection
3942              * with destination server
3943              */
3944             int ret = create_server_ssl_connection(csp);
3945             if (ret != 0)
3946             {
3947                if (csp->server_cert_verification_result != SSL_CERT_VALID &&
3948                    csp->server_cert_verification_result != SSL_CERT_NOT_VERIFIED)
3949                {
3950                   /*
3951                    * If the server certificate is invalid, we must inform
3952                    * the client and then close connection to the client.
3953                    */
3954                   ssl_send_certificate_error(csp);
3955                   close_client_and_server_ssl_connections(csp);
3956                   return;
3957                }
3958                if (csp->server_cert_verification_result == SSL_CERT_NOT_VERIFIED
3959                 || csp->server_cert_verification_result == SSL_CERT_VALID)
3960                {
3961                   /*
3962                    * The TLS/SSL connection wasn't created but an invalid
3963                    * certificate wasn't detected. Report it as connection
3964                    * failure.
3965                    */
3966                   rsp = error_response(csp, "connect-failed");
3967                   if (rsp)
3968                   {
3969                      send_crunch_response(csp, rsp);
3970                   }
3971                   return;
3972                }
3973             }
3974          }
3975       }/* -END- if (http->ssl) */
3976 #endif /* def FEATURE_HTTPS_INSPECTION */
3977
3978 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
3979       save_connection_destination(csp->server_connection.sfd,
3980          http, fwd, &csp->server_connection);
3981       csp->server_connection.keep_alive_timeout =
3982          (unsigned)csp->config->keep_alive_timeout;
3983    }
3984 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
3985
3986    csp->server_connection.requests_sent_total++;
3987
3988    if ((fwd->type == SOCKS_5T) && (NULL == csp->headers->first))
3989    {
3990       /* Client headers have been sent optimistically */
3991       assert(csp->headers->last == NULL);
3992    }
3993    else if (http->ssl == 0 || (fwd->forward_host
3994 #ifdef FEATURE_HTTPS_INSPECTION
3995          && use_ssl_tunnel
3996 #endif
3997            ))
3998    {
3999       if (send_http_request(csp))
4000       {
4001          rsp = error_response(csp, "connect-failed");
4002          if (rsp)
4003          {
4004             send_crunch_response(csp, rsp);
4005          }
4006          return;
4007       }
4008    }
4009    else
4010    {
4011       /*
4012        * Using old solution with SSL tunnel or new solution with SSL proxy
4013        */
4014       list_remove_all(csp->headers);
4015 #ifdef FEATURE_HTTPS_INSPECTION
4016       if (use_ssl_tunnel)
4017 #endif
4018       {
4019          /*
4020          * We're running an SSL tunnel and we're not forwarding,
4021          * so just ditch the client headers, send the "connect succeeded"
4022          * message to the client, flush the rest, and get out of the way.
4023          */
4024          if (write_socket_delayed(csp->cfd, CSUCCEED,
4025                strlen(CSUCCEED), get_write_delay(csp)))
4026          {
4027             return;
4028          }
4029       }
4030 #ifdef FEATURE_HTTPS_INSPECTION
4031       else
4032       {
4033          /*
4034           * If server certificate is invalid, we must inform client and then
4035           * close connection with client.
4036           */
4037          if (csp->server_cert_verification_result != SSL_CERT_VALID)
4038          {
4039             ssl_send_certificate_error(csp);
4040             close_client_and_server_ssl_connections(csp);
4041             return;
4042          }
4043          if (send_https_request(csp))
4044          {
4045             rsp = error_response(csp, "connect-failed");
4046             if (rsp)
4047             {
4048                send_crunch_response(csp, rsp);
4049             }
4050             close_client_and_server_ssl_connections(csp);
4051             return;
4052          }
4053       }
4054 #endif /* def FEATURE_HTTPS_INSPECTION */
4055       clear_iob(csp->client_iob);
4056    }/* -END- else ... if (http->ssl == 1) */
4057
4058    log_error(LOG_LEVEL_CONNECT, "to %s successful", http->hostport);
4059
4060    /* XXX: should the time start earlier for optimistically sent data? */
4061    csp->server_connection.request_sent = time(NULL);
4062
4063    handle_established_connection(csp);
4064    freez(csp->receive_buffer);
4065 }
4066
4067
4068 #ifdef FUZZ
4069 /*********************************************************************
4070  *
4071  * Function    :  fuzz_server_response
4072  *
4073  * Description :  Treat the input as a whole server response.
4074  *
4075  * Parameters  :
4076  *          1  :  csp = Current client state (buffers, headers, etc...)
4077  *          2  :  fuzz_input_file = File to read the input from.
4078  *
4079  * Returns     :  0
4080  *
4081  *********************************************************************/
4082 extern int fuzz_server_response(struct client_state *csp, char *fuzz_input_file)
4083 {
4084    static struct forward_spec fwd; /* Zero'd due to being static */
4085    csp->cfd = 0;
4086
4087    if (strcmp(fuzz_input_file, "-") == 0)
4088    {
4089       /* XXX: Doesn'T work yet. */
4090       csp->server_connection.sfd = 0;
4091    }
4092    else
4093    {
4094       csp->server_connection.sfd = open(fuzz_input_file, O_RDONLY);
4095       if (csp->server_connection.sfd == -1)
4096       {
4097          log_error(LOG_LEVEL_FATAL, "Failed to open %s: %E",
4098             fuzz_input_file);
4099       }
4100    }
4101    csp->fwd = &fwd;
4102    csp->content_type |= CT_GIF;
4103    csp->action->flags |= ACTION_DEANIMATE;
4104    csp->action->string[ACTION_STRING_DEANIMATE] = "last";
4105
4106    csp->http->path = strdup_or_die("/");
4107    csp->http->host = strdup_or_die("fuzz.example.org");
4108    csp->http->hostport = strdup_or_die("fuzz.example.org:80");
4109    /* Prevent client socket monitoring */
4110    csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
4111    csp->flags |= CSP_FLAG_CHUNKED;
4112
4113    csp->config->feature_flags |= RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE;
4114    csp->flags |= CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE;
4115
4116    csp->content_type |= CT_DECLARED|CT_GIF;
4117
4118    csp->config->socket_timeout = 0;
4119
4120    cgi_init_error_messages();
4121
4122    handle_established_connection(csp);
4123    freez(csp->receive_buffer);
4124
4125    return 0;
4126 }
4127 #endif
4128
4129
4130 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4131 /*********************************************************************
4132  *
4133  * Function    :  prepare_csp_for_next_request
4134  *
4135  * Description :  Put the csp in a mostly vergin state.
4136  *
4137  * Parameters  :
4138  *          1  :  csp = Current client state (buffers, headers, etc...)
4139  *
4140  * Returns     :  N/A
4141  *
4142  *********************************************************************/
4143 static void prepare_csp_for_next_request(struct client_state *csp)
4144 {
4145    csp->content_type = 0;
4146    csp->content_length = 0;
4147    csp->expected_content_length = 0;
4148    csp->expected_client_content_length = 0;
4149    list_remove_all(csp->headers);
4150    clear_iob(csp->iob);
4151    freez(csp->error_message);
4152    free_http_request(csp->http);
4153    destroy_list(csp->headers);
4154    destroy_list(csp->tags);
4155 #ifdef FEATURE_CLIENT_TAGS
4156    destroy_list(csp->client_tags);
4157    freez(csp->client_address);
4158 #endif
4159    free_current_action(csp->action);
4160    if (NULL != csp->fwd)
4161    {
4162       unload_forward_spec(csp->fwd);
4163       csp->fwd = NULL;
4164    }
4165    /* XXX: Store per-connection flags someplace else. */
4166    csp->flags = (CSP_FLAG_ACTIVE | CSP_FLAG_REUSED_CLIENT_CONNECTION);
4167 #ifdef FEATURE_TOGGLE
4168    if (global_toggle_state)
4169 #endif /* def FEATURE_TOGGLE */
4170    {
4171       csp->flags |= CSP_FLAG_TOGGLED_ON;
4172    }
4173
4174    if (csp->client_iob->eod > csp->client_iob->cur)
4175    {
4176       long bytes_to_shift = csp->client_iob->cur - csp->client_iob->buf;
4177       size_t data_length  = (size_t)(csp->client_iob->eod - csp->client_iob->cur);
4178
4179       assert(bytes_to_shift > 0);
4180       assert(data_length > 0);
4181
4182       log_error(LOG_LEVEL_CONNECT, "Shifting %d pipelined bytes by %d bytes",
4183          data_length, bytes_to_shift);
4184       memmove(csp->client_iob->buf, csp->client_iob->cur, data_length);
4185       csp->client_iob->cur = csp->client_iob->buf;
4186       assert(csp->client_iob->eod == csp->client_iob->buf + bytes_to_shift + data_length);
4187       csp->client_iob->eod = csp->client_iob->buf + data_length;
4188       memset(csp->client_iob->eod, '\0', (size_t)bytes_to_shift);
4189
4190       csp->flags |= CSP_FLAG_PIPELINED_REQUEST_WAITING;
4191    }
4192    else
4193    {
4194       /*
4195        * We mainly care about resetting client_iob->cur so we don't
4196        * waste buffer space at the beginning and don't mess up the
4197        * request restoration done by cgi_show_request().
4198        *
4199        * Freeing the buffer itself isn't technically necessary,
4200        * but makes debugging more convenient.
4201        */
4202       clear_iob(csp->client_iob);
4203    }
4204 }
4205 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
4206
4207
4208 /*********************************************************************
4209  *
4210  * Function    :  serve
4211  *
4212  * Description :  This is little more than chat.  We only "serve" to
4213  *                to close (or remember) any socket that chat may have
4214  *                opened.
4215  *
4216  * Parameters  :
4217  *          1  :  csp = Current client state (buffers, headers, etc...)
4218  *
4219  * Returns     :  N/A
4220  *
4221  *********************************************************************/
4222 static void serve(struct client_state *csp)
4223 {
4224    int config_file_change_detected = 0; /* Only used for debugging */
4225 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4226 #ifdef FEATURE_CONNECTION_SHARING
4227    static int monitor_thread_running = 0;
4228 #endif /* def FEATURE_CONNECTION_SHARING */
4229    int continue_chatting = 0;
4230
4231    log_error(LOG_LEVEL_CONNECT, "Accepted connection from %s on socket %d",
4232       csp->ip_addr_str, csp->cfd);
4233
4234    do
4235    {
4236       unsigned int latency;
4237
4238       chat(csp);
4239
4240       /*
4241        * If the request has been crunched,
4242        * the calculated latency is zero.
4243        */
4244       latency = (unsigned)(csp->server_connection.response_received -
4245          csp->server_connection.request_sent) / 2;
4246
4247       if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4248          && (csp->flags & CSP_FLAG_CRUNCHED)
4249          && (csp->expected_client_content_length != 0))
4250       {
4251          csp->flags |= CSP_FLAG_SERVER_SOCKET_TAINTED;
4252          log_error(LOG_LEVEL_CONNECT,
4253             "Tainting client socket %d due to unread data.", csp->cfd);
4254       }
4255
4256       continue_chatting = (csp->config->feature_flags
4257          & RUNTIME_FEATURE_CONNECTION_KEEP_ALIVE)
4258          && !(csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4259          && (csp->cfd != JB_INVALID_SOCKET)
4260          && (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4261          && ((csp->flags & CSP_FLAG_SERVER_CONTENT_LENGTH_SET)
4262             || (csp->flags & CSP_FLAG_CHUNKED));
4263
4264       if (!(csp->flags & CSP_FLAG_CRUNCHED)
4265          && (csp->server_connection.sfd != JB_INVALID_SOCKET))
4266       {
4267          if (!(csp->flags & CSP_FLAG_SERVER_KEEP_ALIVE_TIMEOUT_SET))
4268          {
4269             csp->server_connection.keep_alive_timeout = csp->config->default_server_timeout;
4270          }
4271          if (!(csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE)
4272             || (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED)
4273             || !socket_is_still_alive(csp->server_connection.sfd)
4274             || !(latency < csp->server_connection.keep_alive_timeout))
4275          {
4276             log_error(LOG_LEVEL_CONNECT,
4277                "Closing server socket %d connected to %s. "
4278                "Keep-alive %u. Tainted: %u. Socket alive %u. Timeout: %u.",
4279                csp->server_connection.sfd, csp->server_connection.host,
4280                0 != (csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE),
4281                0 != (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED),
4282                socket_is_still_alive(csp->server_connection.sfd),
4283                csp->server_connection.keep_alive_timeout);
4284 #ifdef FEATURE_CONNECTION_SHARING
4285             if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4286             {
4287                forget_connection(csp->server_connection.sfd);
4288             }
4289 #endif /* def FEATURE_CONNECTION_SHARING */
4290             close_socket(csp->server_connection.sfd);
4291             mark_connection_closed(&csp->server_connection);
4292          }
4293       }
4294
4295       if (continue_chatting && any_loaded_file_changed(csp))
4296       {
4297          continue_chatting = 0;
4298          config_file_change_detected = 1;
4299       }
4300
4301       if (continue_chatting)
4302       {
4303          if (((csp->flags & CSP_FLAG_PIPELINED_REQUEST_WAITING) != 0)
4304             && socket_is_still_alive(csp->cfd))
4305          {
4306             log_error(LOG_LEVEL_CONNECT, "Client request %d has been "
4307                "pipelined on socket %d and the socket is still alive.",
4308                csp->requests_received_total+1, csp->cfd);
4309             prepare_csp_for_next_request(csp);
4310             continue;
4311          }
4312
4313          if (0 != (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE))
4314          {
4315             if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4316             {
4317                log_error(LOG_LEVEL_CONNECT,
4318                   "Waiting for the next client request on socket %d. "
4319                   "Keeping the server socket %d to %s open.",
4320                   csp->cfd, csp->server_connection.sfd, csp->server_connection.host);
4321             }
4322             else
4323             {
4324                log_error(LOG_LEVEL_CONNECT,
4325                   "Waiting for the next client request on socket %d. "
4326                   "No server socket to keep open.", csp->cfd);
4327             }
4328          }
4329
4330          if ((csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE)
4331             && data_is_available(csp->cfd, (int)csp->config->keep_alive_timeout)
4332             && socket_is_still_alive(csp->cfd))
4333          {
4334             log_error(LOG_LEVEL_CONNECT,
4335                "Client request %u arrived in time on socket %d.",
4336                csp->requests_received_total+1, csp->cfd);
4337             prepare_csp_for_next_request(csp);
4338          }
4339          else
4340          {
4341 #ifdef FEATURE_CONNECTION_SHARING
4342             if ((csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4343                && (csp->server_connection.sfd != JB_INVALID_SOCKET)
4344                && (socket_is_still_alive(csp->server_connection.sfd)))
4345             {
4346                time_t time_open = time(NULL) - csp->server_connection.timestamp;
4347
4348                if (csp->server_connection.keep_alive_timeout < time_open - (time_t)latency)
4349                {
4350                   break;
4351                }
4352
4353                remember_connection(&csp->server_connection);
4354                csp->server_connection.sfd = JB_INVALID_SOCKET;
4355                drain_and_close_socket(csp->cfd);
4356                csp->cfd = JB_INVALID_SOCKET;
4357                privoxy_mutex_lock(&connection_reuse_mutex);
4358                if (!monitor_thread_running)
4359                {
4360                   monitor_thread_running = 1;
4361                   privoxy_mutex_unlock(&connection_reuse_mutex);
4362                   wait_for_alive_connections();
4363                   privoxy_mutex_lock(&connection_reuse_mutex);
4364                   monitor_thread_running = 0;
4365                }
4366                privoxy_mutex_unlock(&connection_reuse_mutex);
4367             }
4368 #endif /* def FEATURE_CONNECTION_SHARING */
4369             break;
4370          }
4371       }
4372       else if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4373       {
4374          log_error(LOG_LEVEL_CONNECT,
4375             "Closing server socket %d connected to %s. Keep-alive: %u. "
4376             "Tainted: %u. Socket alive: %u. Timeout: %u. "
4377             "Configuration file change detected: %u",
4378             csp->server_connection.sfd, csp->server_connection.host,
4379             0 != (csp->flags & CSP_FLAG_SERVER_CONNECTION_KEEP_ALIVE),
4380             0 != (csp->flags & CSP_FLAG_SERVER_SOCKET_TAINTED),
4381             socket_is_still_alive(csp->server_connection.sfd),
4382             csp->server_connection.keep_alive_timeout,
4383             config_file_change_detected);
4384       }
4385    } while (continue_chatting);
4386
4387 #else
4388    chat(csp);
4389 #endif /* def FEATURE_CONNECTION_KEEP_ALIVE */
4390
4391    if (csp->server_connection.sfd != JB_INVALID_SOCKET)
4392    {
4393 #ifdef FEATURE_CONNECTION_SHARING
4394       if (csp->config->feature_flags & RUNTIME_FEATURE_CONNECTION_SHARING)
4395       {
4396          forget_connection(csp->server_connection.sfd);
4397       }
4398 #endif /* def FEATURE_CONNECTION_SHARING */
4399       close_socket(csp->server_connection.sfd);
4400    }
4401
4402 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
4403    mark_connection_closed(&csp->server_connection);
4404 #endif
4405
4406    if (csp->cfd != JB_INVALID_SOCKET)
4407    {
4408       log_error(LOG_LEVEL_CONNECT, "Closing client socket %d. "
4409          "Keep-alive: %u. Socket alive: %u. Data available: %u. "
4410          "Configuration file change detected: %u. Requests received: %u.",
4411          csp->cfd, 0 != (csp->flags & CSP_FLAG_CLIENT_CONNECTION_KEEP_ALIVE),
4412          socket_is_still_alive(csp->cfd), data_is_available(csp->cfd, 0),
4413          config_file_change_detected, csp->requests_received_total);
4414       drain_and_close_socket(csp->cfd);
4415    }
4416
4417    free_csp_resources(csp);
4418
4419    csp->flags &= ~CSP_FLAG_ACTIVE;
4420
4421 }
4422
4423
4424 #ifdef __BEOS__
4425 /*********************************************************************
4426  *
4427  * Function    :  server_thread
4428  *
4429  * Description :  We only exist to call `serve' in a threaded environment.
4430  *
4431  * Parameters  :
4432  *          1  :  data = Current client state (buffers, headers, etc...)
4433  *
4434  * Returns     :  Always 0.
4435  *
4436  *********************************************************************/
4437 static int32 server_thread(void *data)
4438 {
4439    serve((struct client_state *) data);
4440    return 0;
4441
4442 }
4443 #endif
4444
4445
4446 #if !defined(_WIN32) || defined(_WIN_CONSOLE)
4447 /*********************************************************************
4448  *
4449  * Function    :  usage
4450  *
4451  * Description :  Print usage info & exit.
4452  *
4453  * Parameters  :  Pointer to argv[0] for identifying ourselves
4454  *
4455  * Returns     :  No. ,-)
4456  *
4457  *********************************************************************/
4458 static void usage(const char *name)
4459 {
4460    printf("Privoxy version " VERSION " (" HOME_PAGE_URL ")\n"
4461           "Usage: %s [--config-test] "
4462 #if defined(unix)
4463           "[--chroot] "
4464 #endif /* defined(unix) */
4465           "[--help] "
4466 #if defined(unix)
4467           "[--no-daemon] [--pidfile pidfile] [--pre-chroot-nslookup hostname] [--user user[.group]] "
4468 #endif /* defined(unix) */
4469          "[--version] [configfile]\n",
4470           name);
4471
4472 #ifdef FUZZ
4473    show_fuzz_usage(name);
4474 #endif
4475
4476    printf("Aborting\n");
4477
4478    exit(2);
4479
4480 }
4481 #endif /* #if !defined