1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23 #include "curl_setup.h"
24
25 #if !defined(CURL_DISABLE_PROXY)
26
27 #ifdef HAVE_NETINET_IN_H
28 #include <netinet/in.h>
29 #endif
30 #ifdef HAVE_ARPA_INET_H
31 #include <arpa/inet.h>
32 #endif
33
34 #include "urldata.h"
35 #include "sendf.h"
36 #include "strequal.h"
37 #include "select.h"
38 #include "connect.h"
39 #include "timeval.h"
40 #include "socks.h"
41
42 /* The last #include file should be: */
43 #include "memdebug.h"
44
45 /*
46 * Helper read-from-socket functions. Does the same as Curl_read() but it
47 * blocks until all bytes amount of buffersize will be read. No more, no less.
48 *
49 * This is STUPID BLOCKING behaviour which we frown upon, but right now this
50 * is what we have...
51 */
Curl_blockread_all(struct connectdata * conn,curl_socket_t sockfd,char * buf,ssize_t buffersize,ssize_t * n)52 int Curl_blockread_all(struct connectdata *conn, /* connection data */
53 curl_socket_t sockfd, /* read from this socket */
54 char *buf, /* store read data here */
55 ssize_t buffersize, /* max amount to read */
56 ssize_t *n) /* amount bytes read */
57 {
58 ssize_t nread;
59 ssize_t allread = 0;
60 int result;
61 long timeleft;
62 *n = 0;
63 for(;;) {
64 timeleft = Curl_timeleft(conn->data, NULL, TRUE);
65 if(timeleft < 0) {
66 /* we already got the timeout */
67 result = CURLE_OPERATION_TIMEDOUT;
68 break;
69 }
70 if(Curl_socket_ready(sockfd, CURL_SOCKET_BAD, timeleft) <= 0) {
71 result = ~CURLE_OK;
72 break;
73 }
74 result = Curl_read_plain(sockfd, buf, buffersize, &nread);
75 if(CURLE_AGAIN == result)
76 continue;
77 else if(result)
78 break;
79
80 if(buffersize == nread) {
81 allread += nread;
82 *n = allread;
83 result = CURLE_OK;
84 break;
85 }
86 if(!nread) {
87 result = ~CURLE_OK;
88 break;
89 }
90
91 buffersize -= nread;
92 buf += nread;
93 allread += nread;
94 }
95 return result;
96 }
97
98 /*
99 * This function logs in to a SOCKS4 proxy and sends the specifics to the final
100 * destination server.
101 *
102 * Reference :
103 * http://socks.permeo.com/protocol/socks4.protocol
104 *
105 * Note :
106 * Set protocol4a=true for "SOCKS 4A (Simple Extension to SOCKS 4 Protocol)"
107 * Nonsupport "Identification Protocol (RFC1413)"
108 */
Curl_SOCKS4(const char * proxy_name,const char * hostname,int remote_port,int sockindex,struct connectdata * conn,bool protocol4a)109 CURLcode Curl_SOCKS4(const char *proxy_name,
110 const char *hostname,
111 int remote_port,
112 int sockindex,
113 struct connectdata *conn,
114 bool protocol4a)
115 {
116 #define SOCKS4REQLEN 262
117 unsigned char socksreq[SOCKS4REQLEN]; /* room for SOCKS4 request incl. user
118 id */
119 int result;
120 CURLcode code;
121 curl_socket_t sock = conn->sock[sockindex];
122 struct SessionHandle *data = conn->data;
123
124 if(Curl_timeleft(data, NULL, TRUE) < 0) {
125 /* time-out, bail out, go home */
126 failf(data, "Connection time-out");
127 return CURLE_OPERATION_TIMEDOUT;
128 }
129
130 (void)curlx_nonblock(sock, FALSE);
131
132 infof(data, "SOCKS4 communication to %s:%d\n", hostname, remote_port);
133
134 /*
135 * Compose socks4 request
136 *
137 * Request format
138 *
139 * +----+----+----+----+----+----+----+----+----+----+....+----+
140 * | VN | CD | DSTPORT | DSTIP | USERID |NULL|
141 * +----+----+----+----+----+----+----+----+----+----+....+----+
142 * # of bytes: 1 1 2 4 variable 1
143 */
144
145 socksreq[0] = 4; /* version (SOCKS4) */
146 socksreq[1] = 1; /* connect */
147 socksreq[2] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
148 socksreq[3] = (unsigned char)(remote_port & 0xff); /* PORT LSB */
149
150 /* DNS resolve only for SOCKS4, not SOCKS4a */
151 if(!protocol4a) {
152 struct Curl_dns_entry *dns;
153 Curl_addrinfo *hp=NULL;
154 int rc;
155
156 rc = Curl_resolv(conn, hostname, remote_port, &dns);
157
158 if(rc == CURLRESOLV_ERROR)
159 return CURLE_COULDNT_RESOLVE_PROXY;
160
161 if(rc == CURLRESOLV_PENDING)
162 /* ignores the return code, but 'dns' remains NULL on failure */
163 (void)Curl_resolver_wait_resolv(conn, &dns);
164
165 /*
166 * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
167 * returns a Curl_addrinfo pointer that may not always look the same.
168 */
169 if(dns)
170 hp=dns->addr;
171 if(hp) {
172 char buf[64];
173 unsigned short ip[4];
174 Curl_printable_address(hp, buf, sizeof(buf));
175
176 if(4 == sscanf( buf, "%hu.%hu.%hu.%hu",
177 &ip[0], &ip[1], &ip[2], &ip[3])) {
178 /* Set DSTIP */
179 socksreq[4] = (unsigned char)ip[0];
180 socksreq[5] = (unsigned char)ip[1];
181 socksreq[6] = (unsigned char)ip[2];
182 socksreq[7] = (unsigned char)ip[3];
183 }
184 else
185 hp = NULL; /* fail! */
186
187 infof(data, "SOCKS4 connect to %s (locally resolved)\n", buf);
188
189 Curl_resolv_unlock(data, dns); /* not used anymore from now on */
190
191 }
192 if(!hp) {
193 failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.",
194 hostname);
195 return CURLE_COULDNT_RESOLVE_HOST;
196 }
197 }
198
199 /*
200 * This is currently not supporting "Identification Protocol (RFC1413)".
201 */
202 socksreq[8] = 0; /* ensure empty userid is NUL-terminated */
203 if(proxy_name) {
204 size_t plen = strlen(proxy_name);
205 if(plen >= sizeof(socksreq) - 8) {
206 failf(data, "Too long SOCKS proxy name, can't use!\n");
207 return CURLE_COULDNT_CONNECT;
208 }
209 /* copy the proxy name WITH trailing zero */
210 memcpy(socksreq + 8, proxy_name, plen+1);
211 }
212
213 /*
214 * Make connection
215 */
216 {
217 ssize_t actualread;
218 ssize_t written;
219 ssize_t hostnamelen = 0;
220 int packetsize = 9 +
221 (int)strlen((char*)socksreq + 8); /* size including NUL */
222
223 /* If SOCKS4a, set special invalid IP address 0.0.0.x */
224 if(protocol4a) {
225 socksreq[4] = 0;
226 socksreq[5] = 0;
227 socksreq[6] = 0;
228 socksreq[7] = 1;
229 /* If still enough room in buffer, also append hostname */
230 hostnamelen = (ssize_t)strlen(hostname) + 1; /* length including NUL */
231 if(packetsize + hostnamelen <= SOCKS4REQLEN)
232 strcpy((char*)socksreq + packetsize, hostname);
233 else
234 hostnamelen = 0; /* Flag: hostname did not fit in buffer */
235 }
236
237 /* Send request */
238 code = Curl_write_plain(conn, sock, (char *)socksreq,
239 packetsize + hostnamelen,
240 &written);
241 if(code || (written != packetsize + hostnamelen)) {
242 failf(data, "Failed to send SOCKS4 connect request.");
243 return CURLE_COULDNT_CONNECT;
244 }
245 if(protocol4a && hostnamelen == 0) {
246 /* SOCKS4a with very long hostname - send that name separately */
247 hostnamelen = (ssize_t)strlen(hostname) + 1;
248 code = Curl_write_plain(conn, sock, (char *)hostname, hostnamelen,
249 &written);
250 if(code || (written != hostnamelen)) {
251 failf(data, "Failed to send SOCKS4 connect request.");
252 return CURLE_COULDNT_CONNECT;
253 }
254 }
255
256 packetsize = 8; /* receive data size */
257
258 /* Receive response */
259 result = Curl_blockread_all(conn, sock, (char *)socksreq, packetsize,
260 &actualread);
261 if(result || (actualread != packetsize)) {
262 failf(data, "Failed to receive SOCKS4 connect request ack.");
263 return CURLE_COULDNT_CONNECT;
264 }
265
266 /*
267 * Response format
268 *
269 * +----+----+----+----+----+----+----+----+
270 * | VN | CD | DSTPORT | DSTIP |
271 * +----+----+----+----+----+----+----+----+
272 * # of bytes: 1 1 2 4
273 *
274 * VN is the version of the reply code and should be 0. CD is the result
275 * code with one of the following values:
276 *
277 * 90: request granted
278 * 91: request rejected or failed
279 * 92: request rejected because SOCKS server cannot connect to
280 * identd on the client
281 * 93: request rejected because the client program and identd
282 * report different user-ids
283 */
284
285 /* wrong version ? */
286 if(socksreq[0] != 0) {
287 failf(data,
288 "SOCKS4 reply has wrong version, version should be 4.");
289 return CURLE_COULDNT_CONNECT;
290 }
291
292 /* Result */
293 switch(socksreq[1]) {
294 case 90:
295 infof(data, "SOCKS4%s request granted.\n", protocol4a?"a":"");
296 break;
297 case 91:
298 failf(data,
299 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
300 ", request rejected or failed.",
301 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
302 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
303 ((socksreq[8] << 8) | socksreq[9]),
304 socksreq[1]);
305 return CURLE_COULDNT_CONNECT;
306 case 92:
307 failf(data,
308 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
309 ", request rejected because SOCKS server cannot connect to "
310 "identd on the client.",
311 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
312 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
313 ((socksreq[8] << 8) | socksreq[9]),
314 socksreq[1]);
315 return CURLE_COULDNT_CONNECT;
316 case 93:
317 failf(data,
318 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
319 ", request rejected because the client program and identd "
320 "report different user-ids.",
321 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
322 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
323 ((socksreq[8] << 8) | socksreq[9]),
324 socksreq[1]);
325 return CURLE_COULDNT_CONNECT;
326 default:
327 failf(data,
328 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
329 ", Unknown.",
330 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
331 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
332 ((socksreq[8] << 8) | socksreq[9]),
333 socksreq[1]);
334 return CURLE_COULDNT_CONNECT;
335 }
336 }
337
338 (void)curlx_nonblock(sock, TRUE);
339
340 return CURLE_OK; /* Proxy was successful! */
341 }
342
343 /*
344 * This function logs in to a SOCKS5 proxy and sends the specifics to the final
345 * destination server.
346 */
Curl_SOCKS5(const char * proxy_name,const char * proxy_password,const char * hostname,int remote_port,int sockindex,struct connectdata * conn)347 CURLcode Curl_SOCKS5(const char *proxy_name,
348 const char *proxy_password,
349 const char *hostname,
350 int remote_port,
351 int sockindex,
352 struct connectdata *conn)
353 {
354 /*
355 According to the RFC1928, section "6. Replies". This is what a SOCK5
356 replies:
357
358 +----+-----+-------+------+----------+----------+
359 |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
360 +----+-----+-------+------+----------+----------+
361 | 1 | 1 | X'00' | 1 | Variable | 2 |
362 +----+-----+-------+------+----------+----------+
363
364 Where:
365
366 o VER protocol version: X'05'
367 o REP Reply field:
368 o X'00' succeeded
369 */
370
371 unsigned char socksreq[600]; /* room for large user/pw (255 max each) */
372 ssize_t actualread;
373 ssize_t written;
374 int result;
375 CURLcode code;
376 curl_socket_t sock = conn->sock[sockindex];
377 struct SessionHandle *data = conn->data;
378 long timeout;
379 bool socks5_resolve_local = (conn->proxytype == CURLPROXY_SOCKS5)?TRUE:FALSE;
380 const size_t hostname_len = strlen(hostname);
381 ssize_t len = 0;
382
383 /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
384 if(!socks5_resolve_local && hostname_len > 255) {
385 infof(conn->data, "SOCKS5: server resolving disabled for hostnames of "
386 "length > 255 [actual len=%zu]\n", hostname_len);
387 socks5_resolve_local = TRUE;
388 }
389
390 /* get timeout */
391 timeout = Curl_timeleft(data, NULL, TRUE);
392
393 if(timeout < 0) {
394 /* time-out, bail out, go home */
395 failf(data, "Connection time-out");
396 return CURLE_OPERATION_TIMEDOUT;
397 }
398
399 (void)curlx_nonblock(sock, TRUE);
400
401 /* wait until socket gets connected */
402 result = Curl_socket_ready(CURL_SOCKET_BAD, sock, timeout);
403
404 if(-1 == result) {
405 failf(conn->data, "SOCKS5: no connection here");
406 return CURLE_COULDNT_CONNECT;
407 }
408 else if(0 == result) {
409 failf(conn->data, "SOCKS5: connection timeout");
410 return CURLE_OPERATION_TIMEDOUT;
411 }
412
413 if(result & CURL_CSELECT_ERR) {
414 failf(conn->data, "SOCKS5: error occurred during connection");
415 return CURLE_COULDNT_CONNECT;
416 }
417
418 socksreq[0] = 5; /* version */
419 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
420 socksreq[1] = (char)(proxy_name ? 3 : 2); /* number of methods (below) */
421 socksreq[2] = 0; /* no authentication */
422 socksreq[3] = 1; /* GSS-API */
423 socksreq[4] = 2; /* username/password */
424 #else
425 socksreq[1] = (char)(proxy_name ? 2 : 1); /* number of methods (below) */
426 socksreq[2] = 0; /* no authentication */
427 socksreq[3] = 2; /* username/password */
428 #endif
429
430 (void)curlx_nonblock(sock, FALSE);
431
432 code = Curl_write_plain(conn, sock, (char *)socksreq, (2 + (int)socksreq[1]),
433 &written);
434 if(code || (written != (2 + (int)socksreq[1]))) {
435 failf(data, "Unable to send initial SOCKS5 request.");
436 return CURLE_COULDNT_CONNECT;
437 }
438
439 (void)curlx_nonblock(sock, TRUE);
440
441 result = Curl_socket_ready(sock, CURL_SOCKET_BAD, timeout);
442
443 if(-1 == result) {
444 failf(conn->data, "SOCKS5 nothing to read");
445 return CURLE_COULDNT_CONNECT;
446 }
447 else if(0 == result) {
448 failf(conn->data, "SOCKS5 read timeout");
449 return CURLE_OPERATION_TIMEDOUT;
450 }
451
452 if(result & CURL_CSELECT_ERR) {
453 failf(conn->data, "SOCKS5 read error occurred");
454 return CURLE_RECV_ERROR;
455 }
456
457 (void)curlx_nonblock(sock, FALSE);
458
459 result=Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
460 if(result || (actualread != 2)) {
461 failf(data, "Unable to receive initial SOCKS5 response.");
462 return CURLE_COULDNT_CONNECT;
463 }
464
465 if(socksreq[0] != 5) {
466 failf(data, "Received invalid version in initial SOCKS5 response.");
467 return CURLE_COULDNT_CONNECT;
468 }
469 if(socksreq[1] == 0) {
470 /* Nothing to do, no authentication needed */
471 ;
472 }
473 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
474 else if(socksreq[1] == 1) {
475 code = Curl_SOCKS5_gssapi_negotiate(sockindex, conn);
476 if(code) {
477 failf(data, "Unable to negotiate SOCKS5 GSS-API context.");
478 return CURLE_COULDNT_CONNECT;
479 }
480 }
481 #endif
482 else if(socksreq[1] == 2) {
483 /* Needs user name and password */
484 size_t proxy_name_len, proxy_password_len;
485 if(proxy_name && proxy_password) {
486 proxy_name_len = strlen(proxy_name);
487 proxy_password_len = strlen(proxy_password);
488 }
489 else {
490 proxy_name_len = 0;
491 proxy_password_len = 0;
492 }
493
494 /* username/password request looks like
495 * +----+------+----------+------+----------+
496 * |VER | ULEN | UNAME | PLEN | PASSWD |
497 * +----+------+----------+------+----------+
498 * | 1 | 1 | 1 to 255 | 1 | 1 to 255 |
499 * +----+------+----------+------+----------+
500 */
501 len = 0;
502 socksreq[len++] = 1; /* username/pw subnegotiation version */
503 socksreq[len++] = (unsigned char) proxy_name_len;
504 if(proxy_name && proxy_name_len)
505 memcpy(socksreq + len, proxy_name, proxy_name_len);
506 len += proxy_name_len;
507 socksreq[len++] = (unsigned char) proxy_password_len;
508 if(proxy_password && proxy_password_len)
509 memcpy(socksreq + len, proxy_password, proxy_password_len);
510 len += proxy_password_len;
511
512 code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
513 if(code || (len != written)) {
514 failf(data, "Failed to send SOCKS5 sub-negotiation request.");
515 return CURLE_COULDNT_CONNECT;
516 }
517
518 result=Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
519 if(result || (actualread != 2)) {
520 failf(data, "Unable to receive SOCKS5 sub-negotiation response.");
521 return CURLE_COULDNT_CONNECT;
522 }
523
524 /* ignore the first (VER) byte */
525 if(socksreq[1] != 0) { /* status */
526 failf(data, "User was rejected by the SOCKS5 server (%d %d).",
527 socksreq[0], socksreq[1]);
528 return CURLE_COULDNT_CONNECT;
529 }
530
531 /* Everything is good so far, user was authenticated! */
532 }
533 else {
534 /* error */
535 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
536 if(socksreq[1] == 255) {
537 #else
538 if(socksreq[1] == 1) {
539 failf(data,
540 "SOCKS5 GSSAPI per-message authentication is not supported.");
541 return CURLE_COULDNT_CONNECT;
542 }
543 else if(socksreq[1] == 255) {
544 #endif
545 if(!proxy_name || !*proxy_name) {
546 failf(data,
547 "No authentication method was acceptable. (It is quite likely"
548 " that the SOCKS5 server wanted a username/password, since none"
549 " was supplied to the server on this connection.)");
550 }
551 else {
552 failf(data, "No authentication method was acceptable.");
553 }
554 return CURLE_COULDNT_CONNECT;
555 }
556 else {
557 failf(data,
558 "Undocumented SOCKS5 mode attempted to be used by server.");
559 return CURLE_COULDNT_CONNECT;
560 }
561 }
562
563 /* Authentication is complete, now specify destination to the proxy */
564 len = 0;
565 socksreq[len++] = 5; /* version (SOCKS5) */
566 socksreq[len++] = 1; /* connect */
567 socksreq[len++] = 0; /* must be zero */
568
569 if(!socks5_resolve_local) {
570 socksreq[len++] = 3; /* ATYP: domain name = 3 */
571 socksreq[len++] = (char) hostname_len; /* address length */
572 memcpy(&socksreq[len], hostname, hostname_len); /* address str w/o NULL */
573 len += hostname_len;
574 }
575 else {
576 struct Curl_dns_entry *dns;
577 Curl_addrinfo *hp = NULL;
578 int rc = Curl_resolv(conn, hostname, remote_port, &dns);
579
580 if(rc == CURLRESOLV_ERROR)
581 return CURLE_COULDNT_RESOLVE_HOST;
582
583 if(rc == CURLRESOLV_PENDING) {
584 /* this requires that we're in "wait for resolve" state */
585 code = Curl_resolver_wait_resolv(conn, &dns);
586 if(code)
587 return code;
588 }
589
590 /*
591 * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
592 * returns a Curl_addrinfo pointer that may not always look the same.
593 */
594 if(dns)
595 hp=dns->addr;
596 if(hp) {
597 struct sockaddr_in *saddr_in;
598 #ifdef ENABLE_IPV6
599 struct sockaddr_in6 *saddr_in6;
600 #endif
601 int i;
602
603 if(hp->ai_family == AF_INET) {
604 socksreq[len++] = 1; /* ATYP: IPv4 = 1 */
605
606 saddr_in = (struct sockaddr_in*)hp->ai_addr;
607 for(i = 0; i < 4; i++) {
608 socksreq[len++] = ((unsigned char*)&saddr_in->sin_addr.s_addr)[i];
609 infof(data, "%d\n", socksreq[len-1]);
610 }
611 }
612 #ifdef ENABLE_IPV6
613 else if(hp->ai_family == AF_INET6) {
614 socksreq[len++] = 4; /* ATYP: IPv6 = 4 */
615
616 saddr_in6 = (struct sockaddr_in6*)hp->ai_addr;
617 for(i = 0; i < 16; i++) {
618 socksreq[len++] = ((unsigned char*)&saddr_in6->sin6_addr.s6_addr)[i];
619 }
620 }
621 #endif
622 else
623 hp = NULL; /* fail! */
624
625 Curl_resolv_unlock(data, dns); /* not used anymore from now on */
626 }
627 if(!hp) {
628 failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.",
629 hostname);
630 return CURLE_COULDNT_RESOLVE_HOST;
631 }
632 }
633
634 socksreq[len++] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
635 socksreq[len++] = (unsigned char)(remote_port & 0xff); /* PORT LSB */
636
637 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
638 if(conn->socks5_gssapi_enctype) {
639 failf(data, "SOCKS5 GSS-API protection not yet implemented.");
640 }
641 else
642 #endif
643 code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
644
645 if(code || (len != written)) {
646 failf(data, "Failed to send SOCKS5 connect request.");
647 return CURLE_COULDNT_CONNECT;
648 }
649
650 len = 10; /* minimum packet size is 10 */
651
652 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
653 if(conn->socks5_gssapi_enctype) {
654 failf(data, "SOCKS5 GSS-API protection not yet implemented.");
655 }
656 else
657 #endif
658 result = Curl_blockread_all(conn, sock, (char *)socksreq,
659 len, &actualread);
660
661 if(result || (len != actualread)) {
662 failf(data, "Failed to receive SOCKS5 connect request ack.");
663 return CURLE_COULDNT_CONNECT;
664 }
665
666 if(socksreq[0] != 5) { /* version */
667 failf(data,
668 "SOCKS5 reply has wrong version, version should be 5.");
669 return CURLE_COULDNT_CONNECT;
670 }
671 if(socksreq[1] != 0) { /* Anything besides 0 is an error */
672 if(socksreq[3] == 1) {
673 failf(data,
674 "Can't complete SOCKS5 connection to %d.%d.%d.%d:%d. (%d)",
675 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
676 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
677 ((socksreq[8] << 8) | socksreq[9]),
678 socksreq[1]);
679 }
680 else if(socksreq[3] == 3) {
681 failf(data,
682 "Can't complete SOCKS5 connection to %s:%d. (%d)",
683 hostname,
684 ((socksreq[8] << 8) | socksreq[9]),
685 socksreq[1]);
686 }
687 else if(socksreq[3] == 4) {
688 failf(data,
689 "Can't complete SOCKS5 connection to %02x%02x:%02x%02x:"
690 "%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%d. (%d)",
691 (unsigned char)socksreq[4], (unsigned char)socksreq[5],
692 (unsigned char)socksreq[6], (unsigned char)socksreq[7],
693 (unsigned char)socksreq[8], (unsigned char)socksreq[9],
694 (unsigned char)socksreq[10], (unsigned char)socksreq[11],
695 (unsigned char)socksreq[12], (unsigned char)socksreq[13],
696 (unsigned char)socksreq[14], (unsigned char)socksreq[15],
697 (unsigned char)socksreq[16], (unsigned char)socksreq[17],
698 (unsigned char)socksreq[18], (unsigned char)socksreq[19],
699 ((socksreq[8] << 8) | socksreq[9]),
700 socksreq[1]);
701 }
702 return CURLE_COULDNT_CONNECT;
703 }
704
705 /* Fix: in general, returned BND.ADDR is variable length parameter by RFC
706 1928, so the reply packet should be read until the end to avoid errors at
707 subsequent protocol level.
708
709 +----+-----+-------+------+----------+----------+
710 |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
711 +----+-----+-------+------+----------+----------+
712 | 1 | 1 | X'00' | 1 | Variable | 2 |
713 +----+-----+-------+------+----------+----------+
714
715 ATYP:
716 o IP v4 address: X'01', BND.ADDR = 4 byte
717 o domain name: X'03', BND.ADDR = [ 1 byte length, string ]
718 o IP v6 address: X'04', BND.ADDR = 16 byte
719 */
720
721 /* Calculate real packet size */
722 if(socksreq[3] == 3) {
723 /* domain name */
724 int addrlen = (int) socksreq[4];
725 len = 5 + addrlen + 2;
726 }
727 else if(socksreq[3] == 4) {
728 /* IPv6 */
729 len = 4 + 16 + 2;
730 }
731
732 /* At this point we already read first 10 bytes */
733 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
734 if(!conn->socks5_gssapi_enctype) {
735 /* decrypt_gssapi_blockread already read the whole packet */
736 #endif
737 if(len > 10) {
738 len -= 10;
739 result = Curl_blockread_all(conn, sock, (char *)&socksreq[10],
740 len, &actualread);
741 if(result || (len != actualread)) {
742 failf(data, "Failed to receive SOCKS5 connect request ack.");
743 return CURLE_COULDNT_CONNECT;
744 }
745 }
746 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
747 }
748 #endif
749
750 (void)curlx_nonblock(sock, TRUE);
751 return CURLE_OK; /* Proxy was successful! */
752 }
753
754 #endif /* CURL_DISABLE_PROXY */
755
756