1/*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2011, 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 "setup.h" 24 25#if !defined(CURL_DISABLE_PROXY) || defined(USE_WINDOWS_SSPI) 26#include <string.h> 27 28#ifdef HAVE_STDLIB_H 29#include <stdlib.h> 30#endif 31#ifdef HAVE_SYS_SOCKET_H 32#include <sys/socket.h> 33#endif 34#ifdef HAVE_NETINET_IN_H 35#include <netinet/in.h> 36#endif 37#ifdef HAVE_ARPA_INET_H 38#include <arpa/inet.h> 39#endif 40 41#include "urldata.h" 42#include "sendf.h" 43#include "strequal.h" 44#include "select.h" 45#include "connect.h" 46#include "timeval.h" 47#include "socks.h" 48 49/* The last #include file should be: */ 50#include "memdebug.h" 51 52/* 53 * Helper read-from-socket functions. Does the same as Curl_read() but it 54 * blocks until all bytes amount of buffersize will be read. No more, no less. 55 * 56 * This is STUPID BLOCKING behaviour which we frown upon, but right now this 57 * is what we have... 58 */ 59int Curl_blockread_all(struct connectdata *conn, /* connection data */ 60 curl_socket_t sockfd, /* read from this socket */ 61 char *buf, /* store read data here */ 62 ssize_t buffersize, /* max amount to read */ 63 ssize_t *n, /* amount bytes read */ 64 long conn_timeout) /* timeout for data wait 65 relative to 66 conn->created */ 67{ 68 ssize_t nread; 69 ssize_t allread = 0; 70 int result; 71 struct timeval tvnow; 72 long conntime; 73 *n = 0; 74 for(;;) { 75 tvnow = Curl_tvnow(); 76 /* calculating how long connection is establishing */ 77 conntime = Curl_tvdiff(tvnow, conn->created); 78 if(conntime > conn_timeout) { 79 /* we already got the timeout */ 80 result = CURLE_OPERATION_TIMEDOUT; 81 break; 82 } 83 if(Curl_socket_ready(sockfd, CURL_SOCKET_BAD, 84 conn_timeout - conntime) <= 0) { 85 result = ~CURLE_OK; 86 break; 87 } 88 result = Curl_read_plain(sockfd, buf, buffersize, &nread); 89 if(CURLE_AGAIN == result) 90 continue; 91 else if(result) 92 break; 93 94 if(buffersize == nread) { 95 allread += nread; 96 *n = allread; 97 result = CURLE_OK; 98 break; 99 } 100 if(!nread) { 101 result = ~CURLE_OK; 102 break; 103 } 104 105 buffersize -= nread; 106 buf += nread; 107 allread += nread; 108 } 109 return result; 110} 111 112/* 113* This function logs in to a SOCKS4 proxy and sends the specifics to the final 114* destination server. 115* 116* Reference : 117* http://socks.permeo.com/protocol/socks4.protocol 118* 119* Note : 120* Set protocol4a=true for "SOCKS 4A (Simple Extension to SOCKS 4 Protocol)" 121* Nonsupport "Identification Protocol (RFC1413)" 122*/ 123CURLcode Curl_SOCKS4(const char *proxy_name, 124 const char *hostname, 125 int remote_port, 126 int sockindex, 127 struct connectdata *conn, 128 bool protocol4a) 129{ 130#define SOCKS4REQLEN 262 131 unsigned char socksreq[SOCKS4REQLEN]; /* room for SOCKS4 request incl. user 132 id */ 133 int result; 134 CURLcode code; 135 curl_socket_t sock = conn->sock[sockindex]; 136 long timeout; 137 struct SessionHandle *data = conn->data; 138 139 /* get timeout */ 140 timeout = Curl_timeleft(data, NULL, TRUE); 141 142 if(timeout < 0) { 143 /* time-out, bail out, go home */ 144 failf(data, "Connection time-out"); 145 return CURLE_OPERATION_TIMEDOUT; 146 } 147 148 curlx_nonblock(sock, FALSE); 149 150 /* 151 * Compose socks4 request 152 * 153 * Request format 154 * 155 * +----+----+----+----+----+----+----+----+----+----+....+----+ 156 * | VN | CD | DSTPORT | DSTIP | USERID |NULL| 157 * +----+----+----+----+----+----+----+----+----+----+....+----+ 158 * # of bytes: 1 1 2 4 variable 1 159 */ 160 161 socksreq[0] = 4; /* version (SOCKS4) */ 162 socksreq[1] = 1; /* connect */ 163 socksreq[2] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */ 164 socksreq[3] = (unsigned char)(remote_port & 0xff); /* PORT LSB */ 165 166 /* DNS resolve only for SOCKS4, not SOCKS4a */ 167 if(!protocol4a) { 168 struct Curl_dns_entry *dns; 169 Curl_addrinfo *hp=NULL; 170 int rc; 171 172 rc = Curl_resolv(conn, hostname, remote_port, &dns); 173 174 if(rc == CURLRESOLV_ERROR) 175 return CURLE_COULDNT_RESOLVE_PROXY; 176 177 if(rc == CURLRESOLV_PENDING) 178 /* ignores the return code, but 'dns' remains NULL on failure */ 179 (void)Curl_resolver_wait_resolv(conn, &dns); 180 181 /* 182 * We cannot use 'hostent' as a struct that Curl_resolv() returns. It 183 * returns a Curl_addrinfo pointer that may not always look the same. 184 */ 185 if(dns) 186 hp=dns->addr; 187 if(hp) { 188 char buf[64]; 189 unsigned short ip[4]; 190 Curl_printable_address(hp, buf, sizeof(buf)); 191 192 if(4 == sscanf( buf, "%hu.%hu.%hu.%hu", 193 &ip[0], &ip[1], &ip[2], &ip[3])) { 194 /* Set DSTIP */ 195 socksreq[4] = (unsigned char)ip[0]; 196 socksreq[5] = (unsigned char)ip[1]; 197 socksreq[6] = (unsigned char)ip[2]; 198 socksreq[7] = (unsigned char)ip[3]; 199 } 200 else 201 hp = NULL; /* fail! */ 202 203 Curl_resolv_unlock(data, dns); /* not used anymore from now on */ 204 205 } 206 if(!hp) { 207 failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.", 208 hostname); 209 return CURLE_COULDNT_RESOLVE_HOST; 210 } 211 } 212 213 /* 214 * This is currently not supporting "Identification Protocol (RFC1413)". 215 */ 216 socksreq[8] = 0; /* ensure empty userid is NUL-terminated */ 217 if(proxy_name) 218 strlcat((char*)socksreq + 8, proxy_name, sizeof(socksreq) - 8); 219 220 /* 221 * Make connection 222 */ 223 { 224 ssize_t actualread; 225 ssize_t written; 226 ssize_t hostnamelen = 0; 227 int packetsize = 9 + 228 (int)strlen((char*)socksreq + 8); /* size including NUL */ 229 230 /* If SOCKS4a, set special invalid IP address 0.0.0.x */ 231 if(protocol4a) { 232 socksreq[4] = 0; 233 socksreq[5] = 0; 234 socksreq[6] = 0; 235 socksreq[7] = 1; 236 /* If still enough room in buffer, also append hostname */ 237 hostnamelen = (ssize_t)strlen(hostname) + 1; /* length including NUL */ 238 if(packetsize + hostnamelen <= SOCKS4REQLEN) 239 strcpy((char*)socksreq + packetsize, hostname); 240 else 241 hostnamelen = 0; /* Flag: hostname did not fit in buffer */ 242 } 243 244 /* Send request */ 245 code = Curl_write_plain(conn, sock, (char *)socksreq, 246 packetsize + hostnamelen, 247 &written); 248 if((code != CURLE_OK) || (written != packetsize + hostnamelen)) { 249 failf(data, "Failed to send SOCKS4 connect request."); 250 return CURLE_COULDNT_CONNECT; 251 } 252 if(protocol4a && hostnamelen == 0) { 253 /* SOCKS4a with very long hostname - send that name separately */ 254 hostnamelen = (ssize_t)strlen(hostname) + 1; 255 code = Curl_write_plain(conn, sock, (char *)hostname, hostnamelen, 256 &written); 257 if((code != CURLE_OK) || (written != hostnamelen)) { 258 failf(data, "Failed to send SOCKS4 connect request."); 259 return CURLE_COULDNT_CONNECT; 260 } 261 } 262 263 packetsize = 8; /* receive data size */ 264 265 /* Receive response */ 266 result = Curl_blockread_all(conn, sock, (char *)socksreq, packetsize, 267 &actualread, timeout); 268 if((result != CURLE_OK) || (actualread != packetsize)) { 269 failf(data, "Failed to receive SOCKS4 connect request ack."); 270 return CURLE_COULDNT_CONNECT; 271 } 272 273 /* 274 * Response format 275 * 276 * +----+----+----+----+----+----+----+----+ 277 * | VN | CD | DSTPORT | DSTIP | 278 * +----+----+----+----+----+----+----+----+ 279 * # of bytes: 1 1 2 4 280 * 281 * VN is the version of the reply code and should be 0. CD is the result 282 * code with one of the following values: 283 * 284 * 90: request granted 285 * 91: request rejected or failed 286 * 92: request rejected because SOCKS server cannot connect to 287 * identd on the client 288 * 93: request rejected because the client program and identd 289 * report different user-ids 290 */ 291 292 /* wrong version ? */ 293 if(socksreq[0] != 0) { 294 failf(data, 295 "SOCKS4 reply has wrong version, version should be 4."); 296 return CURLE_COULDNT_CONNECT; 297 } 298 299 /* Result */ 300 switch(socksreq[1]) { 301 case 90: 302 if(protocol4a) 303 infof(data, "SOCKS4a request granted.\n"); 304 else 305 infof(data, "SOCKS4 request granted.\n"); 306 break; 307 case 91: 308 failf(data, 309 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)" 310 ", request rejected or failed.", 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 92: 317 failf(data, 318 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)" 319 ", request rejected because SOCKS server cannot connect to " 320 "identd on the client.", 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 case 93: 327 failf(data, 328 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)" 329 ", request rejected because the client program and identd " 330 "report different user-ids.", 331 (unsigned char)socksreq[4], (unsigned char)socksreq[5], 332 (unsigned char)socksreq[6], (unsigned char)socksreq[7], 333 ((socksreq[8] << 8) | socksreq[9]), 334 socksreq[1]); 335 return CURLE_COULDNT_CONNECT; 336 default: 337 failf(data, 338 "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)" 339 ", Unknown.", 340 (unsigned char)socksreq[4], (unsigned char)socksreq[5], 341 (unsigned char)socksreq[6], (unsigned char)socksreq[7], 342 ((socksreq[8] << 8) | socksreq[9]), 343 socksreq[1]); 344 return CURLE_COULDNT_CONNECT; 345 } 346 } 347 348 curlx_nonblock(sock, TRUE); 349 350 return CURLE_OK; /* Proxy was successful! */ 351} 352 353/* 354 * This function logs in to a SOCKS5 proxy and sends the specifics to the final 355 * destination server. 356 */ 357CURLcode Curl_SOCKS5(const char *proxy_name, 358 const char *proxy_password, 359 const char *hostname, 360 int remote_port, 361 int sockindex, 362 struct connectdata *conn) 363{ 364 /* 365 According to the RFC1928, section "6. Replies". This is what a SOCK5 366 replies: 367 368 +----+-----+-------+------+----------+----------+ 369 |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT | 370 +----+-----+-------+------+----------+----------+ 371 | 1 | 1 | X'00' | 1 | Variable | 2 | 372 +----+-----+-------+------+----------+----------+ 373 374 Where: 375 376 o VER protocol version: X'05' 377 o REP Reply field: 378 o X'00' succeeded 379 */ 380 381 unsigned char socksreq[600]; /* room for large user/pw (255 max each) */ 382 ssize_t actualread; 383 ssize_t written; 384 int result; 385 CURLcode code; 386 curl_socket_t sock = conn->sock[sockindex]; 387 struct SessionHandle *data = conn->data; 388 long timeout; 389 bool socks5_resolve_local = (bool)(conn->proxytype == CURLPROXY_SOCKS5); 390 const size_t hostname_len = strlen(hostname); 391 ssize_t packetsize = 0; 392 393 /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */ 394 if(!socks5_resolve_local && hostname_len > 255) { 395 infof(conn->data,"SOCKS5: server resolving disabled for hostnames of " 396 "length > 255 [actual len=%zu]\n", hostname_len); 397 socks5_resolve_local = TRUE; 398 } 399 400 /* get timeout */ 401 timeout = Curl_timeleft(data, NULL, TRUE); 402 403 if(timeout < 0) { 404 /* time-out, bail out, go home */ 405 failf(data, "Connection time-out"); 406 return CURLE_OPERATION_TIMEDOUT; 407 } 408 409 curlx_nonblock(sock, TRUE); 410 411 /* wait until socket gets connected */ 412 result = Curl_socket_ready(CURL_SOCKET_BAD, sock, timeout); 413 414 if(-1 == result) { 415 failf(conn->data, "SOCKS5: no connection here"); 416 return CURLE_COULDNT_CONNECT; 417 } 418 else if(0 == result) { 419 failf(conn->data, "SOCKS5: connection timeout"); 420 return CURLE_OPERATION_TIMEDOUT; 421 } 422 423 if(result & CURL_CSELECT_ERR) { 424 failf(conn->data, "SOCKS5: error occurred during connection"); 425 return CURLE_COULDNT_CONNECT; 426 } 427 428 socksreq[0] = 5; /* version */ 429#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 430 socksreq[1] = (char)(proxy_name ? 3 : 2); /* number of methods (below) */ 431 socksreq[2] = 0; /* no authentication */ 432 socksreq[3] = 1; /* gssapi */ 433 socksreq[4] = 2; /* username/password */ 434#else 435 socksreq[1] = (char)(proxy_name ? 2 : 1); /* number of methods (below) */ 436 socksreq[2] = 0; /* no authentication */ 437 socksreq[3] = 2; /* username/password */ 438#endif 439 440 curlx_nonblock(sock, FALSE); 441 442 code = Curl_write_plain(conn, sock, (char *)socksreq, (2 + (int)socksreq[1]), 443 &written); 444 if((code != CURLE_OK) || (written != (2 + (int)socksreq[1]))) { 445 failf(data, "Unable to send initial SOCKS5 request."); 446 return CURLE_COULDNT_CONNECT; 447 } 448 449 curlx_nonblock(sock, TRUE); 450 451 result = Curl_socket_ready(sock, CURL_SOCKET_BAD, timeout); 452 453 if(-1 == result) { 454 failf(conn->data, "SOCKS5 nothing to read"); 455 return CURLE_COULDNT_CONNECT; 456 } 457 else if(0 == result) { 458 failf(conn->data, "SOCKS5 read timeout"); 459 return CURLE_OPERATION_TIMEDOUT; 460 } 461 462 if(result & CURL_CSELECT_ERR) { 463 failf(conn->data, "SOCKS5 read error occurred"); 464 return CURLE_RECV_ERROR; 465 } 466 467 curlx_nonblock(sock, FALSE); 468 469 result=Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread, 470 timeout); 471 if((result != CURLE_OK) || (actualread != 2)) { 472 failf(data, "Unable to receive initial SOCKS5 response."); 473 return CURLE_COULDNT_CONNECT; 474 } 475 476 if(socksreq[0] != 5) { 477 failf(data, "Received invalid version in initial SOCKS5 response."); 478 return CURLE_COULDNT_CONNECT; 479 } 480 if(socksreq[1] == 0) { 481 /* Nothing to do, no authentication needed */ 482 ; 483 } 484#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 485 else if(socksreq[1] == 1) { 486 code = Curl_SOCKS5_gssapi_negotiate(sockindex, conn); 487 if(code != CURLE_OK) { 488 failf(data, "Unable to negotiate SOCKS5 gssapi context."); 489 return CURLE_COULDNT_CONNECT; 490 } 491 } 492#endif 493 else if(socksreq[1] == 2) { 494 /* Needs user name and password */ 495 size_t userlen, pwlen; 496 int len; 497 if(proxy_name && proxy_password) { 498 userlen = strlen(proxy_name); 499 pwlen = strlen(proxy_password); 500 } 501 else { 502 userlen = 0; 503 pwlen = 0; 504 } 505 506 /* username/password request looks like 507 * +----+------+----------+------+----------+ 508 * |VER | ULEN | UNAME | PLEN | PASSWD | 509 * +----+------+----------+------+----------+ 510 * | 1 | 1 | 1 to 255 | 1 | 1 to 255 | 511 * +----+------+----------+------+----------+ 512 */ 513 len = 0; 514 socksreq[len++] = 1; /* username/pw subnegotiation version */ 515 socksreq[len++] = (unsigned char) userlen; 516 if(proxy_name && userlen) 517 memcpy(socksreq + len, proxy_name, userlen); 518 len += (int)userlen; 519 socksreq[len++] = (unsigned char) pwlen; 520 if(proxy_password && pwlen) 521 memcpy(socksreq + len, proxy_password, pwlen); 522 len += (int)pwlen; 523 524 code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written); 525 if((code != CURLE_OK) || (len != written)) { 526 failf(data, "Failed to send SOCKS5 sub-negotiation request."); 527 return CURLE_COULDNT_CONNECT; 528 } 529 530 result=Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread, 531 timeout); 532 if((result != CURLE_OK) || (actualread != 2)) { 533 failf(data, "Unable to receive SOCKS5 sub-negotiation response."); 534 return CURLE_COULDNT_CONNECT; 535 } 536 537 /* ignore the first (VER) byte */ 538 if(socksreq[1] != 0) { /* status */ 539 failf(data, "User was rejected by the SOCKS5 server (%d %d).", 540 socksreq[0], socksreq[1]); 541 return CURLE_COULDNT_CONNECT; 542 } 543 544 /* Everything is good so far, user was authenticated! */ 545 } 546 else { 547 /* error */ 548#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 549 if(socksreq[1] == 255) { 550#else 551 if(socksreq[1] == 1) { 552 failf(data, 553 "SOCKS5 GSSAPI per-message authentication is not supported."); 554 return CURLE_COULDNT_CONNECT; 555 } 556 else if(socksreq[1] == 255) { 557#endif 558 if(!proxy_name || !*proxy_name) { 559 failf(data, 560 "No authentication method was acceptable. (It is quite likely" 561 " that the SOCKS5 server wanted a username/password, since none" 562 " was supplied to the server on this connection.)"); 563 } 564 else { 565 failf(data, "No authentication method was acceptable."); 566 } 567 return CURLE_COULDNT_CONNECT; 568 } 569 else { 570 failf(data, 571 "Undocumented SOCKS5 mode attempted to be used by server."); 572 return CURLE_COULDNT_CONNECT; 573 } 574 } 575 576 /* Authentication is complete, now specify destination to the proxy */ 577 socksreq[0] = 5; /* version (SOCKS5) */ 578 socksreq[1] = 1; /* connect */ 579 socksreq[2] = 0; /* must be zero */ 580 581 if(!socks5_resolve_local) { 582 packetsize = (ssize_t)(5 + hostname_len + 2); 583 584 socksreq[3] = 3; /* ATYP: domain name = 3 */ 585 socksreq[4] = (char) hostname_len; /* address length */ 586 memcpy(&socksreq[5], hostname, hostname_len); /* address bytes w/o NULL */ 587 588 /* PORT MSB */ 589 socksreq[hostname_len+5] = (unsigned char)((remote_port >> 8) & 0xff); 590 /* PORT LSB */ 591 socksreq[hostname_len+6] = (unsigned char)(remote_port & 0xff); 592 } 593 else { 594 struct Curl_dns_entry *dns; 595 Curl_addrinfo *hp=NULL; 596 int rc = Curl_resolv(conn, hostname, remote_port, &dns); 597 598 packetsize = 10; 599 600 socksreq[3] = 1; /* IPv4 = 1 */ 601 602 if(rc == CURLRESOLV_ERROR) 603 return CURLE_COULDNT_RESOLVE_HOST; 604 605 if(rc == CURLRESOLV_PENDING) { 606 /* this requires that we're in "wait for resolve" state */ 607 code = Curl_resolver_wait_resolv(conn, &dns); 608 if(code != CURLE_OK) 609 return code; 610 } 611 612 /* 613 * We cannot use 'hostent' as a struct that Curl_resolv() returns. It 614 * returns a Curl_addrinfo pointer that may not always look the same. 615 */ 616 if(dns) 617 hp=dns->addr; 618 if(hp) { 619 char buf[64]; 620 unsigned short ip[4]; 621 Curl_printable_address(hp, buf, sizeof(buf)); 622 623 if(4 == sscanf( buf, "%hu.%hu.%hu.%hu", 624 &ip[0], &ip[1], &ip[2], &ip[3])) { 625 socksreq[4] = (unsigned char)ip[0]; 626 socksreq[5] = (unsigned char)ip[1]; 627 socksreq[6] = (unsigned char)ip[2]; 628 socksreq[7] = (unsigned char)ip[3]; 629 } 630 else 631 hp = NULL; /* fail! */ 632 633 Curl_resolv_unlock(data, dns); /* not used anymore from now on */ 634 } 635 if(!hp) { 636 failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.", 637 hostname); 638 return CURLE_COULDNT_RESOLVE_HOST; 639 } 640 641 socksreq[8] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */ 642 socksreq[9] = (unsigned char)(remote_port & 0xff); /* PORT LSB */ 643 } 644 645#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 646 if(conn->socks5_gssapi_enctype) { 647 failf(data, "SOCKS5 gssapi protection not yet implemented."); 648 } 649 else 650#endif 651 code = Curl_write_plain(conn, sock, (char *)socksreq, packetsize, 652 &written); 653 if((code != CURLE_OK) || (written != packetsize)) { 654 failf(data, "Failed to send SOCKS5 connect request."); 655 return CURLE_COULDNT_CONNECT; 656 } 657 658 packetsize = 10; /* minimum packet size is 10 */ 659 660#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 661 if(conn->socks5_gssapi_enctype) { 662 failf(data, "SOCKS5 gssapi protection not yet implemented."); 663 } 664 else 665#endif 666 result = Curl_blockread_all(conn, sock, (char *)socksreq, packetsize, 667 &actualread, timeout); 668 if((result != CURLE_OK) || (actualread != packetsize)) { 669 failf(data, "Failed to receive SOCKS5 connect request ack."); 670 return CURLE_COULDNT_CONNECT; 671 } 672 673 if(socksreq[0] != 5) { /* version */ 674 failf(data, 675 "SOCKS5 reply has wrong version, version should be 5."); 676 return CURLE_COULDNT_CONNECT; 677 } 678 if(socksreq[1] != 0) { /* Anything besides 0 is an error */ 679 failf(data, 680 "Can't complete SOCKS5 connection to %d.%d.%d.%d:%d. (%d)", 681 (unsigned char)socksreq[4], (unsigned char)socksreq[5], 682 (unsigned char)socksreq[6], (unsigned char)socksreq[7], 683 ((socksreq[8] << 8) | socksreq[9]), 684 socksreq[1]); 685 return CURLE_COULDNT_CONNECT; 686 } 687 688 /* Fix: in general, returned BND.ADDR is variable length parameter by RFC 689 1928, so the reply packet should be read until the end to avoid errors at 690 subsequent protocol level. 691 692 +----+-----+-------+------+----------+----------+ 693 |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT | 694 +----+-----+-------+------+----------+----------+ 695 | 1 | 1 | X'00' | 1 | Variable | 2 | 696 +----+-----+-------+------+----------+----------+ 697 698 ATYP: 699 o IP v4 address: X'01', BND.ADDR = 4 byte 700 o domain name: X'03', BND.ADDR = [ 1 byte length, string ] 701 o IP v6 address: X'04', BND.ADDR = 16 byte 702 */ 703 704 /* Calculate real packet size */ 705 if(socksreq[3] == 3) { 706 /* domain name */ 707 int addrlen = (int) socksreq[4]; 708 packetsize = 5 + addrlen + 2; 709 } 710 else if(socksreq[3] == 4) { 711 /* IPv6 */ 712 packetsize = 4 + 16 + 2; 713 } 714 715 /* At this point we already read first 10 bytes */ 716#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 717 if(!conn->socks5_gssapi_enctype) { 718 /* decrypt_gssapi_blockread already read the whole packet */ 719#endif 720 if(packetsize > 10) { 721 packetsize -= 10; 722 result = Curl_blockread_all(conn, sock, (char *)&socksreq[10], 723 packetsize, &actualread, timeout); 724 if((result != CURLE_OK) || (actualread != packetsize)) { 725 failf(data, "Failed to receive SOCKS5 connect request ack."); 726 return CURLE_COULDNT_CONNECT; 727 } 728 } 729#if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI) 730 } 731#endif 732 733 curlx_nonblock(sock, TRUE); 734 return CURLE_OK; /* Proxy was successful! */ 735} 736 737#endif /* CURL_DISABLE_PROXY */ 738 739