1 /*********************************************************************
2 *
3 * File : $Source: /cvsroot/ijbswa/current/jbsockets.c,v $
4 *
5 * Purpose : Contains wrappers for system-specific sockets code,
6 * so that the rest of Privoxy can be more
7 * OS-independent. Contains #ifdefs to make this work
8 * on many platforms.
9 *
10 * Copyright : Written by and Copyright (C) 2001-2017 the
11 * Privoxy team. https://www.privoxy.org/
12 *
13 * Based on the Internet Junkbuster originally written
14 * by and Copyright (C) 1997 Anonymous Coders and
15 * Junkbusters Corporation. http://www.junkbusters.com
16 *
17 * This program is free software; you can redistribute it
18 * and/or modify it under the terms of the GNU General
19 * Public License as published by the Free Software
20 * Foundation; either version 2 of the License, or (at
21 * your option) any later version.
22 *
23 * This program is distributed in the hope that it will
24 * be useful, but WITHOUT ANY WARRANTY; without even the
25 * implied warranty of MERCHANTABILITY or FITNESS FOR A
26 * PARTICULAR PURPOSE. See the GNU General Public
27 * License for more details.
28 *
29 * The GNU General Public License should be included with
30 * this file. If not, you can view it at
31 * http://www.gnu.org/copyleft/gpl.html
32 * or write to the Free Software Foundation, Inc., 59
33 * Temple Place - Suite 330, Boston, MA 02111-1307, USA.
34 *
35 *********************************************************************/
36
37
38 #include "config.h"
39
40 #include <stdlib.h>
41 #include <stdio.h>
42 #include <string.h>
43 #include <errno.h>
44 #include <fcntl.h>
45 #include <sys/types.h>
46
47 #ifdef _WIN32
48
49 #ifndef STRICT
50 #define STRICT
51 #endif
52 #include <winsock2.h>
53 #include <windows.h>
54 #include <sys/timeb.h>
55 #include <io.h>
56
57 #else
58
59 #include <unistd.h>
60 #include <sys/time.h>
61 #include <netinet/in.h>
62 #include <sys/ioctl.h>
63 #include <netdb.h>
64 #include <sys/socket.h>
65
66 #ifndef __BEOS__
67 #include <netinet/tcp.h>
68 #include <arpa/inet.h>
69 #else
70 #include <socket.h>
71 #endif
72
73 #endif
74
75 #ifdef HAVE_POLL
76 #ifdef __GLIBC__
77 #include <sys/poll.h>
78 #else
79 #include <poll.h>
80 #endif /* def __GLIBC__ */
81 #endif /* HAVE_POLL */
82
83 #include "project.h"
84
85 /* For mutex semaphores only */
86 #include "jcc.h"
87
88 #include "jbsockets.h"
89 #include "filters.h"
90 #include "errlog.h"
91 #include "miscutil.h"
92
93 /* Mac OSX doesn't define AI_NUMERICSESRV */
94 #ifndef AI_NUMERICSERV
95 #define AI_NUMERICSERV 0
96 #endif
97
98 /*
99 * Maximum number of gethostbyname(_r) retries in case of
100 * soft errors (TRY_AGAIN).
101 * XXX: Does it make sense to make this a config option?
102 */
103 #define MAX_DNS_RETRIES 10
104
105 #ifdef HAVE_RFC2553
106 static jb_socket rfc2553_connect_to(const char *host, int portnum, struct client_state *csp);
107 #else
108 static jb_socket no_rfc2553_connect_to(const char *host, int portnum, struct client_state *csp);
109 #endif
110
111 /*********************************************************************
112 *
113 * Function : set_no_delay_flag
114 *
115 * Description : Disables the Nagle algorithm (TCP send coalescence)
116 * for the given socket.
117 *
118 * Parameters :
119 * 1 : fd = The file descriptor to operate on
120 *
121 * Returns : void
122 *
123 *********************************************************************/
set_no_delay_flag(int fd)124 static void set_no_delay_flag(int fd)
125 {
126 #ifdef TCP_NODELAY
127 int mi = 1;
128
129 if (setsockopt(fd, IPPROTO_TCP, TCP_NODELAY, &mi, sizeof(int)))
130 {
131 log_error(LOG_LEVEL_ERROR,
132 "Failed to disable TCP coalescence for socket %d", fd);
133 }
134 #else
135 #warning set_no_delay_flag() is a nop due to lack of TCP_NODELAY
136 #endif /* def TCP_NODELAY */
137 }
138
139 /*********************************************************************
140 *
141 * Function : connect_to
142 *
143 * Description : Open a socket and connect to it. Will check
144 * that this is allowed according to ACL.
145 *
146 * Parameters :
147 * 1 : host = hostname to connect to
148 * 2 : portnum = port to connect to (XXX: should be unsigned)
149 * 3 : csp = Current client state (buffers, headers, etc...)
150 *
151 * Returns : JB_INVALID_SOCKET => failure, else it is the socket
152 * file descriptor.
153 *
154 *********************************************************************/
connect_to(const char * host,int portnum,struct client_state * csp)155 jb_socket connect_to(const char *host, int portnum, struct client_state *csp)
156 {
157 jb_socket fd;
158 int forwarded_connect_retries = 0;
159
160 do
161 {
162 /*
163 * XXX: The whole errno overloading is ridiculous and should
164 * be replaced with something sane and thread safe
165 */
166 /* errno = 0;*/
167 #ifdef HAVE_RFC2553
168 fd = rfc2553_connect_to(host, portnum, csp);
169 #else
170 fd = no_rfc2553_connect_to(host, portnum, csp);
171 #endif
172 if ((fd != JB_INVALID_SOCKET) || (errno == EINVAL)
173 || (csp->fwd == NULL)
174 || ((csp->fwd->forward_host == NULL) && (csp->fwd->type == SOCKS_NONE)))
175 {
176 break;
177 }
178 forwarded_connect_retries++;
179 if (csp->config->forwarded_connect_retries != 0)
180 {
181 log_error(LOG_LEVEL_ERROR,
182 "Attempt %d of %d to connect to %s failed. Trying again.",
183 forwarded_connect_retries, csp->config->forwarded_connect_retries + 1, host);
184 }
185
186 } while (forwarded_connect_retries < csp->config->forwarded_connect_retries);
187
188 return fd;
189 }
190
191 #ifdef HAVE_RFC2553
192 /* Getaddrinfo implementation */
rfc2553_connect_to(const char * host,int portnum,struct client_state * csp)193 static jb_socket rfc2553_connect_to(const char *host, int portnum, struct client_state *csp)
194 {
195 struct addrinfo hints, *result, *rp;
196 char service[6];
197 int retval;
198 jb_socket fd;
199 #ifdef HAVE_POLL
200 struct pollfd poll_fd[1];
201 #else
202 fd_set wfds;
203 struct timeval timeout;
204 #endif
205 #if !defined(_WIN32) && !defined(__BEOS__)
206 int flags;
207 #endif
208 int connect_failed;
209 /*
210 * XXX: Initializing it here is only necessary
211 * because not all situations are properly
212 * covered yet.
213 */
214 int socket_error = 0;
215
216 #ifdef FEATURE_ACL
217 struct access_control_addr dst[1];
218 #endif /* def FEATURE_ACL */
219
220 /* Don't leak memory when retrying. */
221 freez(csp->error_message);
222 freez(csp->http->host_ip_addr_str);
223
224 retval = snprintf(service, sizeof(service), "%d", portnum);
225 if ((-1 == retval) || (sizeof(service) <= retval))
226 {
227 log_error(LOG_LEVEL_ERROR,
228 "Port number (%d) ASCII decimal representation doesn't fit into 6 bytes",
229 portnum);
230 csp->error_message = strdup("Invalid port number");
231 csp->http->host_ip_addr_str = strdup("unknown");
232 return(JB_INVALID_SOCKET);
233 }
234
235 memset((char *)&hints, 0, sizeof(hints));
236 hints.ai_family = AF_UNSPEC;
237 hints.ai_socktype = SOCK_STREAM;
238 hints.ai_flags = AI_NUMERICSERV; /* avoid service look-up */
239 #ifdef AI_ADDRCONFIG
240 hints.ai_flags |= AI_ADDRCONFIG;
241 #endif
242 if ((retval = getaddrinfo(host, service, &hints, &result)))
243 {
244 log_error(LOG_LEVEL_INFO,
245 "Can not resolve %s: %s", host, gai_strerror(retval));
246 csp->error_message = strdup(gai_strerror(retval));
247 csp->http->host_ip_addr_str = strdup("unknown");
248 /* XXX: Should find a better way to propagate this error. */
249 errno = EINVAL;
250 return(JB_INVALID_SOCKET);
251 }
252
253 csp->http->host_ip_addr_str = malloc_or_die(NI_MAXHOST);
254
255 for (rp = result; rp != NULL; rp = rp->ai_next)
256 {
257
258 #ifdef FEATURE_ACL
259 memcpy(&dst->addr, rp->ai_addr, rp->ai_addrlen);
260
261 if (block_acl(dst, csp))
262 {
263 socket_error = errno = EPERM;
264 continue;
265 }
266 #endif /* def FEATURE_ACL */
267
268 retval = getnameinfo(rp->ai_addr, rp->ai_addrlen,
269 csp->http->host_ip_addr_str, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
270 if (retval)
271 {
272 log_error(LOG_LEVEL_ERROR,
273 "Failed to get the host name from the socket structure: %s",
274 gai_strerror(retval));
275 continue;
276 }
277
278 fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
279 #ifdef _WIN32
280 if (fd == JB_INVALID_SOCKET)
281 #else
282 if (fd < 0)
283 #endif
284 {
285 continue;
286 }
287
288 #ifndef HAVE_POLL
289 #ifndef _WIN32
290 if (fd >= FD_SETSIZE)
291 {
292 log_error(LOG_LEVEL_ERROR,
293 "Server socket number too high to use select(): %d >= %d",
294 fd, FD_SETSIZE);
295 close_socket(fd);
296 freeaddrinfo(result);
297 return JB_INVALID_SOCKET;
298 }
299 #endif
300 #endif
301
302 #ifdef FEATURE_EXTERNAL_FILTERS
303 mark_socket_for_close_on_execute(fd);
304 #endif
305
306 set_no_delay_flag(fd);
307
308 #if !defined(_WIN32) && !defined(__BEOS__)
309 if ((flags = fcntl(fd, F_GETFL, 0)) != -1)
310 {
311 flags |= O_NDELAY;
312 fcntl(fd, F_SETFL, flags);
313 }
314 #endif /* !defined(_WIN32) && !defined(__BEOS__) */
315
316 connect_failed = 0;
317 while (connect(fd, rp->ai_addr, rp->ai_addrlen) == JB_INVALID_SOCKET)
318 {
319 #ifdef _WIN32
320 if (errno == WSAEINPROGRESS)
321 #else /* ifndef _WIN32 */
322 if (errno == EINPROGRESS)
323 #endif /* ndef _WIN32 */
324 {
325 break;
326 }
327
328 if (errno != EINTR)
329 {
330 socket_error = errno;
331 close_socket(fd);
332 connect_failed = 1;
333 break;
334 }
335 }
336 if (connect_failed)
337 {
338 continue;
339 }
340
341 #if !defined(_WIN32) && !defined(__BEOS__)
342 if (flags != -1)
343 {
344 flags &= ~O_NDELAY;
345 fcntl(fd, F_SETFL, flags);
346 }
347 #endif /* !defined(_WIN32) && !defined(__BEOS__) */
348
349 #ifdef HAVE_POLL
350 poll_fd[0].fd = fd;
351 poll_fd[0].events = POLLOUT;
352
353 retval = poll(poll_fd, 1, 30000);
354 if (retval == 0)
355 {
356 if (rp->ai_next != NULL)
357 {
358 /* Log this now as we'll try another address next */
359 log_error(LOG_LEVEL_CONNECT,
360 "Could not connect to [%s]:%s: Operation timed out.",
361 csp->http->host_ip_addr_str, service);
362 }
363 else
364 {
365 /*
366 * This is the last address, don't log this now
367 * as it would result in a duplicated log message.
368 */
369 socket_error = ETIMEDOUT;
370 }
371 }
372 else if (retval > 0)
373 #else
374 /* wait for connection to complete */
375 FD_ZERO(&wfds);
376 FD_SET(fd, &wfds);
377
378 memset(&timeout, 0, sizeof(timeout));
379 timeout.tv_sec = 30;
380
381 /* MS Windows uses int, not SOCKET, for the 1st arg of select(). Weird! */
382 if ((select((int)fd + 1, NULL, &wfds, NULL, &timeout) > 0)
383 && FD_ISSET(fd, &wfds))
384 #endif
385 {
386 socklen_t optlen = sizeof(socket_error);
387 if (!getsockopt(fd, SOL_SOCKET, SO_ERROR, &socket_error, &optlen))
388 {
389 if (!socket_error)
390 {
391 /* Connection established, no need to try other addresses. */
392 break;
393 }
394 if (rp->ai_next != NULL)
395 {
396 /*
397 * There's another address we can try, so log that this
398 * one didn't work out. If the last one fails, too,
399 * it will get logged outside the loop body so we don't
400 * have to mention it here.
401 */
402 log_error(LOG_LEVEL_CONNECT, "Could not connect to [%s]:%s: %s.",
403 csp->http->host_ip_addr_str, service, strerror(socket_error));
404 }
405 }
406 else
407 {
408 socket_error = errno;
409 log_error(LOG_LEVEL_ERROR, "Could not get the state of "
410 "the connection to [%s]:%s: %s; dropping connection.",
411 csp->http->host_ip_addr_str, service, strerror(errno));
412 }
413 }
414
415 /* Connection failed, try next address */
416 close_socket(fd);
417 }
418
419 freeaddrinfo(result);
420 if (!rp)
421 {
422 log_error(LOG_LEVEL_CONNECT, "Could not connect to [%s]:%s: %s.",
423 host, service, strerror(socket_error));
424 csp->error_message = strdup(strerror(socket_error));
425 return(JB_INVALID_SOCKET);
426 }
427 log_error(LOG_LEVEL_CONNECT, "Connected to %s[%s]:%s.",
428 host, csp->http->host_ip_addr_str, service);
429
430 return(fd);
431
432 }
433
434 #else /* ndef HAVE_RFC2553 */
435 /* Pre-getaddrinfo implementation */
436
no_rfc2553_connect_to(const char * host,int portnum,struct client_state * csp)437 static jb_socket no_rfc2553_connect_to(const char *host, int portnum, struct client_state *csp)
438 {
439 struct sockaddr_in inaddr;
440 jb_socket fd;
441 unsigned int addr;
442 #ifdef HAVE_POLL
443 struct pollfd poll_fd[1];
444 #else
445 fd_set wfds;
446 struct timeval tv[1];
447 #endif
448 #if !defined(_WIN32) && !defined(__BEOS__)
449 int flags;
450 #endif
451
452 #ifdef FEATURE_ACL
453 struct access_control_addr dst[1];
454 #endif /* def FEATURE_ACL */
455
456 /* Don't leak memory when retrying. */
457 freez(csp->http->host_ip_addr_str);
458
459 memset((char *)&inaddr, 0, sizeof inaddr);
460
461 if ((addr = resolve_hostname_to_ip(host)) == INADDR_NONE)
462 {
463 csp->http->host_ip_addr_str = strdup("unknown");
464 return(JB_INVALID_SOCKET);
465 }
466
467 #ifdef FEATURE_ACL
468 dst->addr = ntohl(addr);
469 dst->port = portnum;
470
471 if (block_acl(dst, csp))
472 {
473 errno = EPERM;
474 return(JB_INVALID_SOCKET);
475 }
476 #endif /* def FEATURE_ACL */
477
478 inaddr.sin_addr.s_addr = addr;
479 inaddr.sin_family = AF_INET;
480 csp->http->host_ip_addr_str = strdup(inet_ntoa(inaddr.sin_addr));
481
482 #ifndef _WIN32
483 if (sizeof(inaddr.sin_port) == sizeof(short))
484 #endif /* ndef _WIN32 */
485 {
486 inaddr.sin_port = htons((unsigned short) portnum);
487 }
488 #ifndef _WIN32
489 else
490 {
491 inaddr.sin_port = htonl((unsigned long)portnum);
492 }
493 #endif /* ndef _WIN32 */
494
495 fd = socket(inaddr.sin_family, SOCK_STREAM, 0);
496 #ifdef _WIN32
497 if (fd == JB_INVALID_SOCKET)
498 #else
499 if (fd < 0)
500 #endif
501 {
502 return(JB_INVALID_SOCKET);
503 }
504
505 #ifndef HAVE_POLL
506 #ifndef _WIN32
507 if (fd >= FD_SETSIZE)
508 {
509 log_error(LOG_LEVEL_ERROR,
510 "Server socket number too high to use select(): %d >= %d",
511 fd, FD_SETSIZE);
512 close_socket(fd);
513 return JB_INVALID_SOCKET;
514 }
515 #endif
516 #endif
517
518 set_no_delay_flag(fd);
519
520 #if !defined(_WIN32) && !defined(__BEOS__)
521 if ((flags = fcntl(fd, F_GETFL, 0)) != -1)
522 {
523 flags |= O_NDELAY;
524 fcntl(fd, F_SETFL, flags);
525 #ifdef FEATURE_EXTERNAL_FILTERS
526 mark_socket_for_close_on_execute(fd);
527 #endif
528 }
529 #endif /* !defined(_WIN32) && !defined(__BEOS__) */
530
531 while (connect(fd, (struct sockaddr *) & inaddr, sizeof inaddr) == JB_INVALID_SOCKET)
532 {
533 #ifdef _WIN32
534 if (errno == WSAEINPROGRESS)
535 #else /* ifndef _WIN32 */
536 if (errno == EINPROGRESS)
537 #endif /* ndef _WIN32 */
538 {
539 break;
540 }
541
542 if (errno != EINTR)
543 {
544 close_socket(fd);
545 return(JB_INVALID_SOCKET);
546 }
547 }
548
549 #if !defined(_WIN32) && !defined(__BEOS__)
550 if (flags != -1)
551 {
552 flags &= ~O_NDELAY;
553 fcntl(fd, F_SETFL, flags);
554 }
555 #endif /* !defined(_WIN32) && !defined(__BEOS__) */
556
557 #ifdef HAVE_POLL
558 poll_fd[0].fd = fd;
559 poll_fd[0].events = POLLOUT;
560
561 if (poll(poll_fd, 1, 30000) <= 0)
562 #else
563 /* wait for connection to complete */
564 FD_ZERO(&wfds);
565 FD_SET(fd, &wfds);
566
567 tv->tv_sec = 30;
568 tv->tv_usec = 0;
569
570 /* MS Windows uses int, not SOCKET, for the 1st arg of select(). Weird! */
571 if (select((int)fd + 1, NULL, &wfds, NULL, tv) <= 0)
572 #endif
573 {
574 close_socket(fd);
575 return(JB_INVALID_SOCKET);
576 }
577 return(fd);
578
579 }
580 #endif /* ndef HAVE_RFC2553 */
581
582
583 /*********************************************************************
584 *
585 * Function : write_socket
586 *
587 * Description : Write the contents of buf (for n bytes) to socket fd.
588 *
589 * Parameters :
590 * 1 : fd = file descriptor (aka. handle) of socket to write to.
591 * 2 : buf = pointer to data to be written.
592 * 3 : len = length of data to be written to the socket "fd".
593 *
594 * Returns : 0 on success (entire buffer sent).
595 * nonzero on error.
596 *
597 *********************************************************************/
write_socket(jb_socket fd,const char * buf,size_t len)598 int write_socket(jb_socket fd, const char *buf, size_t len)
599 {
600 if (len == 0)
601 {
602 return 0;
603 }
604
605 #ifdef FUZZ
606 if (!daemon_mode && fd <= 3)
607 {
608 log_error(LOG_LEVEL_WRITING, "Pretending to write to socket %d: %N", fd, len, buf);
609 return 0;
610 }
611 #endif
612
613 log_error(LOG_LEVEL_WRITING, "to socket %d: %N", fd, len, buf);
614
615 #if defined(_WIN32)
616 return (send(fd, buf, (int)len, 0) != (int)len);
617 #elif defined(__BEOS__)
618 return (send(fd, buf, len, 0) != len);
619 #else
620 return (write(fd, buf, len) != len);
621 #endif
622
623 }
624
625
626 /*********************************************************************
627 *
628 * Function : write_socket_delayed
629 *
630 * Description : Write the contents of buf (for n bytes) to
631 * socket fd, optionally delaying the operation.
632 *
633 * Parameters :
634 * 1 : fd = File descriptor (aka. handle) of socket to write to.
635 * 2 : buf = Pointer to data to be written.
636 * 3 : len = Length of data to be written to the socket "fd".
637 * 4 : delay = Delay in milliseconds.
638 *
639 * Returns : 0 on success (entire buffer sent).
640 * nonzero on error.
641 *
642 *********************************************************************/
write_socket_delayed(jb_socket fd,const char * buf,size_t len,unsigned int delay)643 int write_socket_delayed(jb_socket fd, const char *buf, size_t len, unsigned int delay)
644 {
645 size_t i = 0;
646
647 if (delay == 0)
648 {
649 return write_socket(fd, buf, len);
650 }
651
652 while (i < len)
653 {
654 size_t write_length;
655 enum {MAX_WRITE_LENGTH = 10};
656
657 if ((i + MAX_WRITE_LENGTH) > len)
658 {
659 write_length = len - i;
660 }
661 else
662 {
663 write_length = MAX_WRITE_LENGTH;
664 }
665
666 privoxy_millisleep(delay);
667
668 if (write_socket(fd, buf + i, write_length) != 0)
669 {
670 return 1;
671 }
672 i += write_length;
673 }
674
675 return 0;
676
677 }
678
679
680 /*********************************************************************
681 *
682 * Function : read_socket
683 *
684 * Description : Read from a TCP/IP socket in a platform independent way.
685 *
686 * Parameters :
687 * 1 : fd = file descriptor of the socket to read
688 * 2 : buf = pointer to buffer where data will be written
689 * Must be >= len bytes long.
690 * 3 : len = maximum number of bytes to read
691 *
692 * Returns : On success, the number of bytes read is returned (zero
693 * indicates end of file), and the file position is advanced
694 * by this number. It is not an error if this number is
695 * smaller than the number of bytes requested; this may hap-
696 * pen for example because fewer bytes are actually available
697 * right now (maybe because we were close to end-of-file, or
698 * because we are reading from a pipe, or from a terminal,
699 * or because read() was interrupted by a signal). On error,
700 * -1 is returned, and errno is set appropriately. In this
701 * case it is left unspecified whether the file position (if
702 * any) changes.
703 *
704 *********************************************************************/
read_socket(jb_socket fd,char * buf,int len)705 int read_socket(jb_socket fd, char *buf, int len)
706 {
707 int ret;
708
709 if (len <= 0)
710 {
711 return(0);
712 }
713
714 #if defined(_WIN32)
715 ret = recv(fd, buf, len, 0);
716 #elif defined(__BEOS__)
717 ret = recv(fd, buf, (size_t)len, 0);
718 #else
719 ret = (int)read(fd, buf, (size_t)len);
720 #endif
721
722 if (ret > 0)
723 {
724 log_error(LOG_LEVEL_RECEIVED, "from socket %d: %N", fd, ret, buf);
725 }
726
727 return ret;
728 }
729
730
731 /*********************************************************************
732 *
733 * Function : data_is_available
734 *
735 * Description : Waits for data to arrive on a socket.
736 *
737 * Parameters :
738 * 1 : fd = file descriptor of the socket to read
739 * 2 : seconds_to_wait = number of seconds after which we give up.
740 *
741 * Returns : TRUE if data arrived in time,
742 * FALSE otherwise.
743 *
744 *********************************************************************/
data_is_available(jb_socket fd,int seconds_to_wait)745 int data_is_available(jb_socket fd, int seconds_to_wait)
746 {
747 int n;
748 char buf[10];
749 #ifdef HAVE_POLL
750 struct pollfd poll_fd[1];
751
752 poll_fd[0].fd = fd;
753 poll_fd[0].events = POLLIN;
754
755 n = poll(poll_fd, 1, seconds_to_wait * 1000);
756 #else
757 fd_set rfds;
758 struct timeval timeout;
759
760 memset(&timeout, 0, sizeof(timeout));
761 timeout.tv_sec = seconds_to_wait;
762
763 FD_ZERO(&rfds);
764 FD_SET(fd, &rfds);
765
766 n = select(fd+1, &rfds, NULL, NULL, &timeout);
767 #endif
768
769 /*
770 * XXX: Do we care about the different error conditions?
771 */
772 return ((n == 1) && (1 == recv(fd, buf, 1, MSG_PEEK)));
773 }
774
775
776 /*********************************************************************
777 *
778 * Function : close_socket
779 *
780 * Description : Closes a TCP/IP socket
781 *
782 * Parameters :
783 * 1 : fd = file descriptor of socket to be closed
784 *
785 * Returns : void
786 *
787 *********************************************************************/
close_socket(jb_socket fd)788 void close_socket(jb_socket fd)
789 {
790 #if defined(_WIN32) || defined(__BEOS__)
791 closesocket(fd);
792 #else
793 close(fd);
794 #endif
795 }
796
797
798 /*********************************************************************
799 *
800 * Function : drain_and_close_socket
801 *
802 * Description : Closes a TCP/IP socket after draining unread data
803 *
804 * Parameters :
805 * 1 : fd = file descriptor of the socket to be closed
806 *
807 * Returns : void
808 *
809 *********************************************************************/
drain_and_close_socket(jb_socket fd)810 void drain_and_close_socket(jb_socket fd)
811 {
812 #ifdef FEATURE_CONNECTION_KEEP_ALIVE
813 if (socket_is_still_alive(fd))
814 #endif
815 {
816 int bytes_drained_total = 0;
817 int bytes_drained;
818
819 #ifdef HAVE_SHUTDOWN
820 /* Apparently Windows has shutdown() but not SHUT_WR. */
821 #ifndef SHUT_WR
822 #define SHUT_WR 1
823 #endif
824 if (0 != shutdown(fd, SHUT_WR))
825 {
826 log_error(LOG_LEVEL_CONNECT, "Failed to shutdown socket %d: %E", fd);
827 }
828 #endif
829 #define ARBITRARY_DRAIN_LIMIT 10000
830 do
831 {
832 char drainage[500];
833
834 if (!data_is_available(fd, 0))
835 {
836 /*
837 * If there is no data available right now, don't try
838 * to drain the socket as read_socket() could block.
839 */
840 break;
841 }
842
843 bytes_drained = read_socket(fd, drainage, sizeof(drainage));
844 if (bytes_drained < 0)
845 {
846 log_error(LOG_LEVEL_CONNECT, "Failed to drain socket %d: %E", fd);
847 }
848 else if (bytes_drained > 0)
849 {
850 bytes_drained_total += bytes_drained;
851 if (bytes_drained_total > ARBITRARY_DRAIN_LIMIT)
852 {
853 log_error(LOG_LEVEL_CONNECT, "Giving up draining socket %d", fd);
854 break;
855 }
856 }
857 } while (bytes_drained > 0);
858 if (bytes_drained_total != 0)
859 {
860 log_error(LOG_LEVEL_CONNECT,
861 "Drained %d bytes before closing socket %d", bytes_drained_total, fd);
862 }
863 }
864
865 close_socket(fd);
866
867 }
868
869
870 /*********************************************************************
871 *
872 * Function : bind_port
873 *
874 * Description : Call socket, set socket options, and listen.
875 * Called by listen_loop to "boot up" our proxy address.
876 *
877 * Parameters :
878 * 1 : hostnam = TCP/IP address to bind/listen to
879 * 2 : portnum = port to listen on
880 * 3 : backlog = Listen backlog
881 * 4 : pfd = pointer used to return file descriptor.
882 *
883 * Returns : if success, returns 0 and sets *pfd.
884 * if failure, returns -3 if address is in use,
885 * -2 if address unresolvable,
886 * -1 otherwise
887 *********************************************************************/
bind_port(const char * hostnam,int portnum,int backlog,jb_socket * pfd)888 int bind_port(const char *hostnam, int portnum, int backlog, jb_socket *pfd)
889 {
890 #ifdef HAVE_RFC2553
891 struct addrinfo hints;
892 struct addrinfo *result, *rp;
893 /*
894 * XXX: portnum should be a string to allow symbolic service
895 * names in the configuration file and to avoid the following
896 * int2string.
897 */
898 char servnam[6];
899 int retval;
900 #else
901 struct sockaddr_in inaddr;
902 #endif /* def HAVE_RFC2553 */
903 jb_socket fd;
904 #ifndef _WIN32
905 int one = 1;
906 #endif /* ndef _WIN32 */
907
908 *pfd = JB_INVALID_SOCKET;
909
910 #ifdef HAVE_RFC2553
911 retval = snprintf(servnam, sizeof(servnam), "%d", portnum);
912 if ((-1 == retval) || (sizeof(servnam) <= retval))
913 {
914 log_error(LOG_LEVEL_ERROR,
915 "Port number (%d) ASCII decimal representation doesn't fit into 6 bytes",
916 portnum);
917 return -1;
918 }
919
920 memset(&hints, 0, sizeof(struct addrinfo));
921 if (hostnam == NULL)
922 {
923 /*
924 * XXX: This is a hack. The right thing to do
925 * would be to bind to both AF_INET and AF_INET6.
926 * This will also fail if there is no AF_INET
927 * version available.
928 */
929 hints.ai_family = AF_INET;
930 }
931 else
932 {
933 hints.ai_family = AF_UNSPEC;
934 }
935 hints.ai_socktype = SOCK_STREAM;
936 hints.ai_flags = AI_PASSIVE;
937 hints.ai_protocol = 0; /* Really any stream protocol or TCP only */
938 hints.ai_canonname = NULL;
939 hints.ai_addr = NULL;
940 hints.ai_next = NULL;
941
942 if ((retval = getaddrinfo(hostnam, servnam, &hints, &result)))
943 {
944 log_error(LOG_LEVEL_ERROR,
945 "Can not resolve %s: %s", hostnam, gai_strerror(retval));
946 return -2;
947 }
948 #else
949 memset((char *)&inaddr, '\0', sizeof inaddr);
950
951 inaddr.sin_family = AF_INET;
952 inaddr.sin_addr.s_addr = resolve_hostname_to_ip(hostnam);
953
954 if (inaddr.sin_addr.s_addr == INADDR_NONE)
955 {
956 return(-2);
957 }
958
959 #ifndef _WIN32
960 if (sizeof(inaddr.sin_port) == sizeof(short))
961 #endif /* ndef _WIN32 */
962 {
963 inaddr.sin_port = htons((unsigned short) portnum);
964 }
965 #ifndef _WIN32
966 else
967 {
968 inaddr.sin_port = htonl((unsigned long) portnum);
969 }
970 #endif /* ndef _WIN32 */
971 #endif /* def HAVE_RFC2553 */
972
973 #ifdef HAVE_RFC2553
974 for (rp = result; rp != NULL; rp = rp->ai_next)
975 {
976 fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
977 #else
978 fd = socket(AF_INET, SOCK_STREAM, 0);
979 #endif /* def HAVE_RFC2553 */
980
981 #ifdef _WIN32
982 if (fd == JB_INVALID_SOCKET)
983 #else
984 if (fd < 0)
985 #endif
986 {
987 #ifdef HAVE_RFC2553
988 continue;
989 #else
990 return(-1);
991 #endif
992 }
993
994 #ifdef FEATURE_EXTERNAL_FILTERS
995 mark_socket_for_close_on_execute(fd);
996 #endif
997
998 #ifndef _WIN32
999 /*
1000 * This is not needed for Win32 - in fact, it stops
1001 * duplicate instances of Privoxy from being caught.
1002 *
1003 * On UNIX, we assume the user is sensible enough not
1004 * to start Privoxy multiple times on the same IP.
1005 * Without this, stopping and restarting Privoxy
1006 * from a script fails.
1007 * Note: SO_REUSEADDR is meant to only take over
1008 * sockets which are *not* in listen state in Linux,
1009 * e.g. sockets in TIME_WAIT. YMMV.
1010 */
1011 setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, (char *)&one, sizeof(one));
1012 #endif /* ndef _WIN32 */
1013
1014 #ifdef IP_FREEBIND
1015 setsockopt(fd, IPPROTO_IP, IP_FREEBIND, (char *)&one, sizeof(one));
1016 #endif
1017
1018 #ifdef HAVE_RFC2553
1019 if (bind(fd, rp->ai_addr, rp->ai_addrlen) < 0)
1020 #else
1021 if (bind(fd, (struct sockaddr *)&inaddr, sizeof(inaddr)) < 0)
1022 #endif
1023 {
1024 #ifdef _WIN32
1025 errno = WSAGetLastError();
1026 if (errno == WSAEADDRINUSE)
1027 #else
1028 if (errno == EADDRINUSE)
1029 #endif
1030 {
1031 #ifdef HAVE_RFC2553
1032 freeaddrinfo(result);
1033 #endif
1034 close_socket(fd);
1035 return(-3);
1036 }
1037 else
1038 {
1039 close_socket(fd);
1040 #ifndef HAVE_RFC2553
1041 return(-1);
1042 }
1043 }
1044 #else
1045 }
1046 }
1047 else
1048 {
1049 /* bind() succeeded, escape from for-loop */
1050 /*
1051 * XXX: Support multiple listening sockets (e.g. localhost
1052 * resolves to AF_INET and AF_INET6, but only the first address
1053 * is used
1054 */
1055 break;
1056 }
1057 }
1058
1059 freeaddrinfo(result);
1060 if (rp == NULL)
1061 {
1062 /* All bind()s failed */
1063 return(-1);
1064 }
1065 #endif /* ndef HAVE_RFC2553 */
1066
1067 while (listen(fd, backlog) == -1)
1068 {
1069 if (errno != EINTR)
1070 {
1071 close_socket(fd);
1072 return(-1);
1073 }
1074 }
1075
1076 *pfd = fd;
1077 return 0;
1078
1079 }
1080
1081
1082 /*********************************************************************
1083 *
1084 * Function : get_host_information
1085 *
1086 * Description : Determines the IP address the client used to
1087 * reach us and the hostname associated with it.
1088 *
1089 * XXX: Most of the code has been copy and pasted
1090 * from accept_connection() and not all of the
1091 * ifdefs paths have been tested afterwards.
1092 *
1093 * Parameters :
1094 * 1 : afd = File descriptor returned from accept().
1095 * 2 : ip_address = Pointer to return the pointer to
1096 * the ip address string.
1097 * 3 : port = Pointer to return the pointer to
1098 * the TCP port string.
1099 * 4 : hostname = Pointer to return the pointer to
1100 * the hostname or NULL if the caller
1101 * isn't interested in it.
1102 *
1103 * Returns : void.
1104 *
1105 *********************************************************************/
1106 void get_host_information(jb_socket afd, char **ip_address, char **port,
1107 char **hostname)
1108 {
1109 #ifdef HAVE_RFC2553
1110 struct sockaddr_storage server;
1111 int retval;
1112 #else
1113 struct sockaddr_in server;
1114 struct hostent *host = NULL;
1115 #endif /* HAVE_RFC2553 */
1116 #if defined(_WIN32)
1117 /* according to accept_connection() this fixes a warning. */
1118 int s_length, s_length_provided;
1119 #else
1120 socklen_t s_length, s_length_provided;
1121 #endif
1122 #ifndef HAVE_RFC2553
1123 #if defined(HAVE_GETHOSTBYADDR_R_8_ARGS) || defined(HAVE_GETHOSTBYADDR_R_7_ARGS) || defined(HAVE_GETHOSTBYADDR_R_5_ARGS)
1124 struct hostent result;
1125 #if defined(HAVE_GETHOSTBYADDR_R_5_ARGS)
1126 struct hostent_data hdata;
1127 #else
1128 char hbuf[HOSTENT_BUFFER_SIZE];
1129 int thd_err;
1130 #endif /* def HAVE_GETHOSTBYADDR_R_5_ARGS */
1131 #endif /* def HAVE_GETHOSTBYADDR_R_(8|7|5)_ARGS */
1132 #endif /* ifndef HAVE_RFC2553 */
1133 s_length = s_length_provided = sizeof(server);
1134
1135 if (NULL != hostname)
1136 {
1137 *hostname = NULL;
1138 }
1139 *ip_address = NULL;
1140 *port = NULL;
1141
1142 if (!getsockname(afd, (struct sockaddr *) &server, &s_length))
1143 {
1144 if (s_length > s_length_provided)
1145 {
1146 log_error(LOG_LEVEL_ERROR, "getsockname() truncated server address");
1147 return;
1148 }
1149 /*
1150 * XXX: Workaround for missing header on Windows when
1151 * configured with --disable-ipv6-support.
1152 * The proper fix is to not use NI_MAXSERV in
1153 * that case. It works by accident on other platforms
1154 * as <netdb.h> is included unconditionally there.
1155 */
1156 #ifndef NI_MAXSERV
1157 #define NI_MAXSERV 32
1158 #endif
1159 *port = malloc_or_die(NI_MAXSERV);
1160
1161 #ifdef HAVE_RFC2553
1162 *ip_address = malloc_or_die(NI_MAXHOST);
1163 retval = getnameinfo((struct sockaddr *) &server, s_length,
1164 *ip_address, NI_MAXHOST, *port, NI_MAXSERV,
1165 NI_NUMERICHOST|NI_NUMERICSERV);
1166 if (retval)
1167 {
1168 log_error(LOG_LEVEL_ERROR,
1169 "Unable to print my own IP address: %s", gai_strerror(retval));
1170 freez(*ip_address);
1171 freez(*port);
1172 return;
1173 }
1174 #else
1175 *ip_address = strdup(inet_ntoa(server.sin_addr));
1176 snprintf(*port, NI_MAXSERV, "%hu", ntohs(server.sin_port));
1177 #endif /* HAVE_RFC2553 */
1178 if (NULL == hostname)
1179 {
1180 /*
1181 * We're done here, the caller isn't
1182 * interested in knowing the hostname.
1183 */
1184 return;
1185 }
1186
1187 #ifdef HAVE_RFC2553
1188 *hostname = malloc_or_die(NI_MAXHOST);
1189 retval = getnameinfo((struct sockaddr *) &server, s_length,
1190 *hostname, NI_MAXHOST, NULL, 0, NI_NAMEREQD);
1191 if (retval)
1192 {
1193 log_error(LOG_LEVEL_ERROR,
1194 "Unable to resolve my own IP address: %s", gai_strerror(retval));
1195 freez(*hostname);
1196 }
1197 #else
1198 #if defined(HAVE_GETHOSTBYADDR_R_8_ARGS)
1199 gethostbyaddr_r((const char *)&server.sin_addr,
1200 sizeof(server.sin_addr), AF_INET,
1201 &result, hbuf, HOSTENT_BUFFER_SIZE,
1202 &host, &thd_err);
1203 #elif defined(HAVE_GETHOSTBYADDR_R_7_ARGS)
1204 host = gethostbyaddr_r((const char *)&server.sin_addr,
1205 sizeof(server.sin_addr), AF_INET,
1206 &result, hbuf, HOSTENT_BUFFER_SIZE, &thd_err);
1207 #elif defined(HAVE_GETHOSTBYADDR_R_5_ARGS)
1208 if (0 == gethostbyaddr_r((const char *)&server.sin_addr,
1209 sizeof(server.sin_addr), AF_INET,
1210 &result, &hdata))
1211 {
1212 host = &result;
1213 }
1214 else
1215 {
1216 host = NULL;
1217 }
1218 #elif defined(MUTEX_LOCKS_AVAILABLE)
1219 privoxy_mutex_lock(&resolver_mutex);
1220 host = gethostbyaddr((const char *)&server.sin_addr,
1221 sizeof(server.sin_addr), AF_INET);
1222 privoxy_mutex_unlock(&resolver_mutex);
1223 #else
1224 host = gethostbyaddr((const char *)&server.sin_addr,
1225 sizeof(server.sin_addr), AF_INET);
1226 #endif
1227 if (host == NULL)
1228 {
1229 log_error(LOG_LEVEL_ERROR, "Unable to get my own hostname: %E\n");
1230 }
1231 else
1232 {
1233 *hostname = strdup(host->h_name);
1234 }
1235 #endif /* else def HAVE_RFC2553 */
1236 }
1237
1238 return;
1239 }
1240
1241
1242 /*********************************************************************
1243 *
1244 * Function : accept_connection
1245 *
1246 * Description : Accepts a connection on one of possibly multiple
1247 * sockets. The socket(s) to check must have been
1248 * created using bind_port().
1249 *
1250 * Parameters :
1251 * 1 : csp = Client state, cfd, ip_addr_str, and
1252 * ip_addr_long will be set by this routine.
1253 * 2 : fds = File descriptors returned from bind_port
1254 *
1255 * Returns : when a connection is accepted, it returns 1 (TRUE).
1256 * On an error it returns 0 (FALSE).
1257 *
1258 *********************************************************************/
1259 int accept_connection(struct client_state * csp, jb_socket fds[])
1260 {
1261 #ifdef HAVE_RFC2553
1262 /* XXX: client is stored directly into csp->tcp_addr */
1263 #define client (csp->tcp_addr)
1264 #else
1265 struct sockaddr_in client;
1266 #endif
1267 jb_socket afd;
1268 #if defined(_WIN32)
1269 /* Weirdness - fix a warning. */
1270 int c_length;
1271 #else
1272 socklen_t c_length;
1273 #endif
1274 int retval;
1275 int i;
1276 int max_selected_socket;
1277 #ifdef HAVE_POLL
1278 struct pollfd poll_fds[MAX_LISTENING_SOCKETS];
1279 nfds_t polled_sockets;
1280 #else
1281 fd_set selected_fds;
1282 #endif
1283 jb_socket fd;
1284 const char *host_addr;
1285 size_t listen_addr_size;
1286
1287 c_length = sizeof(client);
1288
1289 #ifdef HAVE_POLL
1290 memset(poll_fds, 0, sizeof(poll_fds));
1291 polled_sockets = 0;
1292 #else
1293 /*
1294 * Wait for a connection on any socket.
1295 * Return immediately if no socket is listening.
1296 * XXX: Why not treat this as fatal error?
1297 */
1298 FD_ZERO(&selected_fds);
1299 #endif
1300 max_selected_socket = 0;
1301 for (i = 0; i < MAX_LISTENING_SOCKETS; i++)
1302 {
1303 if (JB_INVALID_SOCKET != fds[i])
1304 {
1305 #ifdef HAVE_POLL
1306 poll_fds[i].fd = fds[i];
1307 poll_fds[i].events = POLLIN;
1308 polled_sockets++;
1309 #else
1310 FD_SET(fds[i], &selected_fds);
1311 #endif
1312 if (max_selected_socket < fds[i] + 1)
1313 {
1314 max_selected_socket = fds[i] + 1;
1315 }
1316 }
1317 }
1318 if (0 == max_selected_socket)
1319 {
1320 return 0;
1321 }
1322 do
1323 {
1324 #ifdef HAVE_POLL
1325 retval = poll(poll_fds, polled_sockets, -1);
1326 #else
1327 retval = select(max_selected_socket, &selected_fds, NULL, NULL, NULL);
1328 #endif
1329 } while (retval < 0 && errno == EINTR);
1330 if (retval <= 0)
1331 {
1332 if (0 == retval)
1333 {
1334 log_error(LOG_LEVEL_ERROR,
1335 "Waiting on new client failed because select(2) returned 0."
1336 " This should not happen.");
1337 }
1338 else
1339 {
1340 log_error(LOG_LEVEL_ERROR,
1341 "Waiting on new client failed because of problems in select(2): "
1342 "%s.", strerror(errno));
1343 }
1344 return 0;
1345 }
1346 #ifdef HAVE_POLL
1347 for (i = 0; i < MAX_LISTENING_SOCKETS && (poll_fds[i].revents == 0); i++);
1348 #else
1349 for (i = 0; i < MAX_LISTENING_SOCKETS && !FD_ISSET(fds[i], &selected_fds);
1350 i++);
1351 #endif
1352 if (i >= MAX_LISTENING_SOCKETS)
1353 {
1354 log_error(LOG_LEVEL_ERROR,
1355 "select(2) reported connected clients (number = %u, "
1356 "descriptor boundary = %u), but none found.",
1357 retval, max_selected_socket);
1358 return 0;
1359 }
1360 fd = fds[i];
1361
1362 /* Accept selected connection */
1363 #ifdef _WIN32
1364 afd = accept (fd, (struct sockaddr *) &client, &c_length);
1365 if (afd == JB_INVALID_SOCKET)
1366 {
1367 return 0;
1368 }
1369 #else
1370 do
1371 {
1372 afd = accept (fd, (struct sockaddr *) &client, &c_length);
1373 } while (afd < 0 && errno == EINTR);
1374 if (afd < 0)
1375 {
1376 return 0;
1377 }
1378 #endif
1379
1380 #ifdef SO_LINGER
1381 {
1382 struct linger linger_options;
1383 linger_options.l_onoff = 1;
1384 linger_options.l_linger = 5;
1385 if (0 != setsockopt(afd, SOL_SOCKET, SO_LINGER, &linger_options, sizeof(linger_options)))
1386 {
1387 log_error(LOG_LEVEL_ERROR, "Setting SO_LINGER on socket %d failed.", afd);
1388 }
1389 }
1390 #endif
1391
1392 #ifndef HAVE_POLL
1393 #ifndef _WIN32
1394 if (afd >= FD_SETSIZE)
1395 {
1396 log_error(LOG_LEVEL_ERROR,
1397 "Client socket number too high to use select(): %d >= %d",
1398 afd, FD_SETSIZE);
1399 close_socket(afd);
1400 return 0;
1401 }
1402 #endif
1403 #endif
1404
1405 #ifdef FEATURE_EXTERNAL_FILTERS
1406 mark_socket_for_close_on_execute(afd);
1407 #endif
1408
1409 set_no_delay_flag(afd);
1410
1411 csp->cfd = afd;
1412 #ifdef HAVE_RFC2553
1413 csp->ip_addr_str = malloc_or_die(NI_MAXHOST);
1414 retval = getnameinfo((struct sockaddr *) &client, c_length,
1415 csp->ip_addr_str, NI_MAXHOST, NULL, 0, NI_NUMERICHOST);
1416 if (!csp->ip_addr_str || retval)
1417 {
1418 log_error(LOG_LEVEL_ERROR, "Can not save csp->ip_addr_str: %s",
1419 (csp->ip_addr_str) ? gai_strerror(retval) : "Insuffcient memory");
1420 freez(csp->ip_addr_str);
1421 }
1422 #undef client
1423 #else
1424 csp->ip_addr_str = strdup(inet_ntoa(client.sin_addr));
1425 csp->ip_addr_long = ntohl(client.sin_addr.s_addr);
1426 #endif /* def HAVE_RFC2553 */
1427
1428 /*
1429 * Save the name and port of the accepting socket for later lookup.
1430 *
1431 * The string needs space for strlen(...) + 7 characters:
1432 * strlen(haddr[i]) + 1 (':') + 5 (port digits) + 1 ('\0')
1433 */
1434 host_addr = (csp->config->haddr[i] != NULL) ? csp->config->haddr[i] : "";
1435 listen_addr_size = strlen(host_addr) + 7;
1436 csp->listen_addr_str = malloc_or_die(listen_addr_size);
1437 retval = snprintf(csp->listen_addr_str, listen_addr_size,
1438 "%s:%d", host_addr, csp->config->hport[i]);
1439 if ((-1 == retval) || listen_addr_size <= retval)
1440 {
1441 log_error(LOG_LEVEL_ERROR,
1442 "Server name (%s) and port number (%d) ASCII decimal representation"
1443 "don't fit into %lu bytes",
1444 host_addr, csp->config->hport[i], listen_addr_size);
1445 return 0;
1446 }
1447
1448 return 1;
1449
1450 }
1451
1452
1453 /*********************************************************************
1454 *
1455 * Function : resolve_hostname_to_ip
1456 *
1457 * Description : Resolve a hostname to an internet tcp/ip address.
1458 * NULL or an empty string resolve to INADDR_ANY.
1459 *
1460 * Parameters :
1461 * 1 : host = hostname to resolve
1462 *
1463 * Returns : INADDR_NONE => failure, INADDR_ANY or tcp/ip address if successful.
1464 *
1465 *********************************************************************/
1466 unsigned long resolve_hostname_to_ip(const char *host)
1467 {
1468 struct sockaddr_in inaddr;
1469 struct hostent *hostp;
1470 #if defined(HAVE_GETHOSTBYNAME_R_6_ARGS) || defined(HAVE_GETHOSTBYNAME_R_5_ARGS) || defined(HAVE_GETHOSTBYNAME_R_3_ARGS)
1471 struct hostent result;
1472 #if defined(HAVE_GETHOSTBYNAME_R_6_ARGS) || defined(HAVE_GETHOSTBYNAME_R_5_ARGS)
1473 char hbuf[HOSTENT_BUFFER_SIZE];
1474 int thd_err;
1475 #else /* defined(HAVE_GETHOSTBYNAME_R_3_ARGS) */
1476 struct hostent_data hdata;
1477 #endif /* def HAVE_GETHOSTBYNAME_R_(6|5)_ARGS */
1478 #endif /* def HAVE_GETHOSTBYNAME_R_(6|5|3)_ARGS */
1479
1480 if ((host == NULL) || (*host == '\0'))
1481 {
1482 return(INADDR_ANY);
1483 }
1484
1485 memset((char *) &inaddr, 0, sizeof inaddr);
1486
1487 if ((inaddr.sin_addr.s_addr = inet_addr(host)) == -1)
1488 {
1489 unsigned int dns_retries = 0;
1490 #if defined(HAVE_GETHOSTBYNAME_R_6_ARGS)
1491 while (gethostbyname_r(host, &result, hbuf,
1492 HOSTENT_BUFFER_SIZE, &hostp, &thd_err)
1493 && (thd_err == TRY_AGAIN) && (dns_retries++ < MAX_DNS_RETRIES))
1494 {
1495 log_error(LOG_LEVEL_ERROR,
1496 "Timeout #%u while trying to resolve %s. Trying again.",
1497 dns_retries, host);
1498 }
1499 #elif defined(HAVE_GETHOSTBYNAME_R_5_ARGS)
1500 while (NULL == (hostp = gethostbyname_r(host, &result,
1501 hbuf, HOSTENT_BUFFER_SIZE, &thd_err))
1502 && (thd_err == TRY_AGAIN) && (dns_retries++ < MAX_DNS_RETRIES))
1503 {
1504 log_error(LOG_LEVEL_ERROR,
1505 "Timeout #%u while trying to resolve %s. Trying again.",
1506 dns_retries, host);
1507 }
1508 #elif defined(HAVE_GETHOSTBYNAME_R_3_ARGS)
1509 /*
1510 * XXX: Doesn't retry in case of soft errors.
1511 * Does this gethostbyname_r version set h_errno?
1512 */
1513 if (0 == gethostbyname_r(host, &result, &hdata))
1514 {
1515 hostp = &result;
1516 }
1517 else
1518 {
1519 hostp = NULL;
1520 }
1521 #elif defined(MUTEX_LOCKS_AVAILABLE)
1522 privoxy_mutex_lock(&resolver_mutex);
1523 while (NULL == (hostp = gethostbyname(host))
1524 && (h_errno == TRY_AGAIN) && (dns_retries++ < MAX_DNS_RETRIES))
1525 {
1526 log_error(LOG_LEVEL_ERROR,
1527 "Timeout #%u while trying to resolve %s. Trying again.",
1528 dns_retries, host);
1529 }
1530 privoxy_mutex_unlock(&resolver_mutex);
1531 #else
1532 while (NULL == (hostp = gethostbyname(host))
1533 && (h_errno == TRY_AGAIN) && (dns_retries++ < MAX_DNS_RETRIES))
1534 {
1535 log_error(LOG_LEVEL_ERROR,
1536 "Timeout #%u while trying to resolve %s. Trying again.",
1537 dns_retries, host);
1538 }
1539 #endif /* def HAVE_GETHOSTBYNAME_R_(6|5|3)_ARGS */
1540 /*
1541 * On Mac OSX, if a domain exists but doesn't have a type A
1542 * record associated with it, the h_addr member of the struct
1543 * hostent returned by gethostbyname is NULL, even if h_length
1544 * is 4. Therefore the second test below.
1545 */
1546 if (hostp == NULL || hostp->h_addr == NULL)
1547 {
1548 errno = EINVAL;
1549 log_error(LOG_LEVEL_ERROR, "could not resolve hostname %s", host);
1550 return(INADDR_NONE);
1551 }
1552 if (hostp->h_addrtype != AF_INET)
1553 {
1554 #ifdef _WIN32
1555 errno = WSAEPROTOTYPE;
1556 #else
1557 errno = EPROTOTYPE;
1558 #endif
1559 log_error(LOG_LEVEL_ERROR, "hostname %s resolves to unknown address type.", host);
1560 return(INADDR_NONE);
1561 }
1562 memcpy((char *)&inaddr.sin_addr, (char *)hostp->h_addr, sizeof(inaddr.sin_addr));
1563 }
1564 return(inaddr.sin_addr.s_addr);
1565
1566 }
1567
1568
1569 /*********************************************************************
1570 *
1571 * Function : socket_is_still_alive
1572 *
1573 * Description : Figures out whether or not a socket is still alive.
1574 *
1575 * Parameters :
1576 * 1 : sfd = The socket to check.
1577 *
1578 * Returns : TRUE for yes, otherwise FALSE.
1579 *
1580 *********************************************************************/
1581 int socket_is_still_alive(jb_socket sfd)
1582 {
1583 char buf[10];
1584 int no_data_waiting;
1585 #ifdef HAVE_POLL
1586 int poll_result;
1587 struct pollfd poll_fd[1];
1588
1589 memset(poll_fd, 0, sizeof(poll_fd));
1590 poll_fd[0].fd = sfd;
1591 poll_fd[0].events = POLLIN;
1592
1593 poll_result = poll(poll_fd, 1, 0);
1594
1595 if (-1 == poll_result)
1596 {
1597 log_error(LOG_LEVEL_CONNECT, "Polling socket %d failed.", sfd);
1598 return FALSE;
1599 }
1600 no_data_waiting = !(poll_fd[0].revents & POLLIN);
1601 #else
1602 fd_set readable_fds;
1603 struct timeval timeout;
1604 int ret;
1605
1606 memset(&timeout, '\0', sizeof(timeout));
1607 FD_ZERO(&readable_fds);
1608 FD_SET(sfd, &readable_fds);
1609
1610 ret = select((int)sfd+1, &readable_fds, NULL, NULL, &timeout);
1611 if (ret < 0)
1612 {
1613 log_error(LOG_LEVEL_CONNECT, "select() on socket %d failed: %E", sfd);
1614 return FALSE;
1615 }
1616 no_data_waiting = !FD_ISSET(sfd, &readable_fds);
1617 #endif /* def HAVE_POLL */
1618
1619 return (no_data_waiting || (1 == recv(sfd, buf, 1, MSG_PEEK)));
1620 }
1621
1622
1623 #ifdef FEATURE_EXTERNAL_FILTERS
1624 /*********************************************************************
1625 *
1626 * Function : mark_socket_for_close_on_execute
1627 *
1628 * Description : Marks a socket for close on execute.
1629 *
1630 * Used so that external filters have no direct
1631 * access to sockets they shouldn't care about.
1632 *
1633 * Not implemented for all platforms.
1634 *
1635 * Parameters :
1636 * 1 : fd = The socket to mark
1637 *
1638 * Returns : void.
1639 *
1640 *********************************************************************/
1641 void mark_socket_for_close_on_execute(jb_socket fd)
1642 {
1643 #ifdef FEATURE_PTHREAD
1644 int ret;
1645
1646 ret = fcntl(fd, F_SETFD, FD_CLOEXEC);
1647
1648 if (ret == -1)
1649 {
1650 log_error(LOG_LEVEL_ERROR,
1651 "fcntl(%d, F_SETFD, FD_CLOEXEC) failed", fd);
1652 }
1653 #else
1654 #warning "Sockets will be visible to external filters"
1655 #endif
1656 }
1657 #endif /* def FEATURE_EXTERNAL_FILTERS */
1658
1659 /*
1660 Local Variables:
1661 tab-width: 3
1662 end:
1663 */
1664