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