1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel (at) 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 */ 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 */ 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 */ 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
