1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1998-2016 Dag-Erling Smørgrav 5 * Copyright (c) 2013 Michael Gmelin <freebsd@grem.de> 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer 13 * in this position and unchanged. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. The name of the author may not be used to endorse or promote products 18 * derived from this software without specific prior written permission 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 21 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 22 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 23 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 24 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 25 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 29 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __FBSDID("$FreeBSD$"); 34 35 #include <sys/param.h> 36 #include <sys/socket.h> 37 #include <sys/time.h> 38 #include <sys/uio.h> 39 40 #include <netinet/in.h> 41 42 #include <ctype.h> 43 #include <errno.h> 44 #include <fcntl.h> 45 #include <inttypes.h> 46 #include <netdb.h> 47 #include <paths.h> 48 #include <poll.h> 49 #include <pwd.h> 50 #include <stdarg.h> 51 #include <stdlib.h> 52 #include <stdio.h> 53 #include <string.h> 54 #include <unistd.h> 55 56 #ifdef WITH_SSL 57 #include <openssl/x509v3.h> 58 #endif 59 60 #include "fetch.h" 61 #include "common.h" 62 63 64 /*** Local data **************************************************************/ 65 66 /* 67 * Error messages for resolver errors 68 */ 69 static struct fetcherr netdb_errlist[] = { 70 #ifdef EAI_NODATA 71 { EAI_NODATA, FETCH_RESOLV, "Host not found" }, 72 #endif 73 { EAI_AGAIN, FETCH_TEMP, "Transient resolver failure" }, 74 { EAI_FAIL, FETCH_RESOLV, "Non-recoverable resolver failure" }, 75 { EAI_NONAME, FETCH_RESOLV, "No address record" }, 76 { -1, FETCH_UNKNOWN, "Unknown resolver error" } 77 }; 78 79 /* 80 * SOCKS5 error enumerations 81 */ 82 enum SOCKS5_ERR { 83 /* Protocol errors */ 84 SOCKS5_ERR_SELECTION, 85 SOCKS5_ERR_READ_METHOD, 86 SOCKS5_ERR_VER5_ONLY, 87 SOCKS5_ERR_NOMETHODS, 88 SOCKS5_ERR_NOTIMPLEMENTED, 89 SOCKS5_ERR_HOSTNAME_SIZE, 90 SOCKS5_ERR_REQUEST, 91 SOCKS5_ERR_REPLY, 92 SOCKS5_ERR_NON_VER5_RESP, 93 SOCKS5_ERR_GENERAL, 94 SOCKS5_ERR_NOT_ALLOWED, 95 SOCKS5_ERR_NET_UNREACHABLE, 96 SOCKS5_ERR_HOST_UNREACHABLE, 97 SOCKS5_ERR_CONN_REFUSED, 98 SOCKS5_ERR_TTL_EXPIRED, 99 SOCKS5_ERR_COM_UNSUPPORTED, 100 SOCKS5_ERR_ADDR_UNSUPPORTED, 101 SOCKS5_ERR_UNSPECIFIED, 102 /* Configuration errors */ 103 SOCKS5_ERR_BAD_HOST, 104 SOCKS5_ERR_BAD_PROXY_FORMAT, 105 SOCKS5_ERR_BAD_PORT 106 }; 107 108 /* 109 * Error messages for SOCKS5 errors 110 */ 111 static struct fetcherr socks5_errlist[] = { 112 /* SOCKS5 protocol errors */ 113 { SOCKS5_ERR_SELECTION, FETCH_ABORT, "SOCKS5: Failed to send selection method" }, 114 { SOCKS5_ERR_READ_METHOD, FETCH_ABORT, "SOCKS5: Failed to read method" }, 115 { SOCKS5_ERR_VER5_ONLY, FETCH_PROTO, "SOCKS5: Only version 5 is implemented" }, 116 { SOCKS5_ERR_NOMETHODS, FETCH_PROTO, "SOCKS5: No acceptable methods" }, 117 { SOCKS5_ERR_NOTIMPLEMENTED, FETCH_PROTO, "SOCKS5: Method currently not implemented" }, 118 { SOCKS5_ERR_HOSTNAME_SIZE, FETCH_PROTO, "SOCKS5: Hostname size is above 256 bytes" }, 119 { SOCKS5_ERR_REQUEST, FETCH_PROTO, "SOCKS5: Failed to request" }, 120 { SOCKS5_ERR_REPLY, FETCH_PROTO, "SOCKS5: Failed to receive reply" }, 121 { SOCKS5_ERR_NON_VER5_RESP, FETCH_PROTO, "SOCKS5: Server responded with a non-version 5 response" }, 122 { SOCKS5_ERR_GENERAL, FETCH_ABORT, "SOCKS5: General server failure" }, 123 { SOCKS5_ERR_NOT_ALLOWED, FETCH_AUTH, "SOCKS5: Connection not allowed by ruleset" }, 124 { SOCKS5_ERR_NET_UNREACHABLE, FETCH_NETWORK, "SOCKS5: Network unreachable" }, 125 { SOCKS5_ERR_HOST_UNREACHABLE, FETCH_ABORT, "SOCKS5: Host unreachable" }, 126 { SOCKS5_ERR_CONN_REFUSED, FETCH_ABORT, "SOCKS5: Connection refused" }, 127 { SOCKS5_ERR_TTL_EXPIRED, FETCH_TIMEOUT, "SOCKS5: TTL expired" }, 128 { SOCKS5_ERR_COM_UNSUPPORTED, FETCH_PROTO, "SOCKS5: Command not supported" }, 129 { SOCKS5_ERR_ADDR_UNSUPPORTED, FETCH_ABORT, "SOCKS5: Address type not supported" }, 130 { SOCKS5_ERR_UNSPECIFIED, FETCH_UNKNOWN, "SOCKS5: Unspecified error" }, 131 /* Configuration error */ 132 { SOCKS5_ERR_BAD_HOST, FETCH_ABORT, "SOCKS5: Bad proxy host" }, 133 { SOCKS5_ERR_BAD_PROXY_FORMAT, FETCH_ABORT, "SOCKS5: Bad proxy format" }, 134 { SOCKS5_ERR_BAD_PORT, FETCH_ABORT, "SOCKS5: Bad port" } 135 }; 136 137 /* End-of-Line */ 138 static const char ENDL[2] = "\r\n"; 139 140 141 /*** Error-reporting functions ***********************************************/ 142 143 /* 144 * Map error code to string 145 */ 146 static struct fetcherr * 147 fetch_finderr(struct fetcherr *p, int e) 148 { 149 while (p->num != -1 && p->num != e) 150 p++; 151 return (p); 152 } 153 154 /* 155 * Set error code 156 */ 157 void 158 fetch_seterr(struct fetcherr *p, int e) 159 { 160 p = fetch_finderr(p, e); 161 fetchLastErrCode = p->cat; 162 snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string); 163 } 164 165 /* 166 * Set error code according to errno 167 */ 168 void 169 fetch_syserr(void) 170 { 171 switch (errno) { 172 case 0: 173 fetchLastErrCode = FETCH_OK; 174 break; 175 case EPERM: 176 case EACCES: 177 case EROFS: 178 case EAUTH: 179 case ENEEDAUTH: 180 fetchLastErrCode = FETCH_AUTH; 181 break; 182 case ENOENT: 183 case EISDIR: /* XXX */ 184 fetchLastErrCode = FETCH_UNAVAIL; 185 break; 186 case ENOMEM: 187 fetchLastErrCode = FETCH_MEMORY; 188 break; 189 case EBUSY: 190 case EAGAIN: 191 fetchLastErrCode = FETCH_TEMP; 192 break; 193 case EEXIST: 194 fetchLastErrCode = FETCH_EXISTS; 195 break; 196 case ENOSPC: 197 fetchLastErrCode = FETCH_FULL; 198 break; 199 case EADDRINUSE: 200 case EADDRNOTAVAIL: 201 case ENETDOWN: 202 case ENETUNREACH: 203 case ENETRESET: 204 case EHOSTUNREACH: 205 fetchLastErrCode = FETCH_NETWORK; 206 break; 207 case ECONNABORTED: 208 case ECONNRESET: 209 fetchLastErrCode = FETCH_ABORT; 210 break; 211 case ETIMEDOUT: 212 fetchLastErrCode = FETCH_TIMEOUT; 213 break; 214 case ECONNREFUSED: 215 case EHOSTDOWN: 216 fetchLastErrCode = FETCH_DOWN; 217 break; 218 default: 219 fetchLastErrCode = FETCH_UNKNOWN; 220 } 221 snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno)); 222 } 223 224 225 /* 226 * Emit status message 227 */ 228 void 229 fetch_info(const char *fmt, ...) 230 { 231 va_list ap; 232 233 va_start(ap, fmt); 234 vfprintf(stderr, fmt, ap); 235 va_end(ap); 236 fputc('\n', stderr); 237 } 238 239 240 /*** Network-related utility functions ***************************************/ 241 242 /* 243 * Return the default port for a scheme 244 */ 245 int 246 fetch_default_port(const char *scheme) 247 { 248 struct servent *se; 249 250 if ((se = getservbyname(scheme, "tcp")) != NULL) 251 return (ntohs(se->s_port)); 252 if (strcmp(scheme, SCHEME_FTP) == 0) 253 return (FTP_DEFAULT_PORT); 254 if (strcmp(scheme, SCHEME_HTTP) == 0) 255 return (HTTP_DEFAULT_PORT); 256 return (0); 257 } 258 259 /* 260 * Return the default proxy port for a scheme 261 */ 262 int 263 fetch_default_proxy_port(const char *scheme) 264 { 265 if (strcmp(scheme, SCHEME_FTP) == 0) 266 return (FTP_DEFAULT_PROXY_PORT); 267 if (strcmp(scheme, SCHEME_HTTP) == 0) 268 return (HTTP_DEFAULT_PROXY_PORT); 269 return (0); 270 } 271 272 273 /* 274 * Create a connection for an existing descriptor. 275 */ 276 conn_t * 277 fetch_reopen(int sd) 278 { 279 conn_t *conn; 280 int opt = 1; 281 282 /* allocate and fill connection structure */ 283 if ((conn = calloc(1, sizeof(*conn))) == NULL) 284 return (NULL); 285 fcntl(sd, F_SETFD, FD_CLOEXEC); 286 setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt); 287 conn->sd = sd; 288 ++conn->ref; 289 return (conn); 290 } 291 292 293 /* 294 * Bump a connection's reference count. 295 */ 296 conn_t * 297 fetch_ref(conn_t *conn) 298 { 299 300 ++conn->ref; 301 return (conn); 302 } 303 304 305 /* 306 * Resolve an address 307 */ 308 struct addrinfo * 309 fetch_resolve(const char *addr, int port, int af) 310 { 311 char hbuf[256], sbuf[8]; 312 struct addrinfo hints, *res; 313 const char *hb, *he, *sep; 314 const char *host, *service; 315 int err, len; 316 317 /* first, check for a bracketed IPv6 address */ 318 if (*addr == '[') { 319 hb = addr + 1; 320 if ((sep = strchr(hb, ']')) == NULL) { 321 errno = EINVAL; 322 goto syserr; 323 } 324 he = sep++; 325 } else { 326 hb = addr; 327 sep = strchrnul(hb, ':'); 328 he = sep; 329 } 330 331 /* see if we need to copy the host name */ 332 if (*he != '\0') { 333 len = snprintf(hbuf, sizeof(hbuf), 334 "%.*s", (int)(he - hb), hb); 335 if (len < 0) 336 goto syserr; 337 if (len >= (int)sizeof(hbuf)) { 338 errno = ENAMETOOLONG; 339 goto syserr; 340 } 341 host = hbuf; 342 } else { 343 host = hb; 344 } 345 346 /* was it followed by a service name? */ 347 if (*sep == '\0' && port != 0) { 348 if (port < 1 || port > 65535) { 349 errno = EINVAL; 350 goto syserr; 351 } 352 if (snprintf(sbuf, sizeof(sbuf), "%d", port) < 0) 353 goto syserr; 354 service = sbuf; 355 } else if (*sep != '\0') { 356 service = sep + 1; 357 } else { 358 service = NULL; 359 } 360 361 /* resolve */ 362 memset(&hints, 0, sizeof(hints)); 363 hints.ai_family = af; 364 hints.ai_socktype = SOCK_STREAM; 365 hints.ai_flags = AI_ADDRCONFIG; 366 if ((err = getaddrinfo(host, service, &hints, &res)) != 0) { 367 netdb_seterr(err); 368 return (NULL); 369 } 370 return (res); 371 syserr: 372 fetch_syserr(); 373 return (NULL); 374 } 375 376 377 /* 378 * Bind a socket to a specific local address 379 */ 380 int 381 fetch_bind(int sd, int af, const char *addr) 382 { 383 struct addrinfo *cliai, *ai; 384 int err; 385 386 if ((cliai = fetch_resolve(addr, 0, af)) == NULL) 387 return (-1); 388 for (ai = cliai; ai != NULL; ai = ai->ai_next) 389 if ((err = bind(sd, ai->ai_addr, ai->ai_addrlen)) == 0) 390 break; 391 if (err != 0) 392 fetch_syserr(); 393 freeaddrinfo(cliai); 394 return (err == 0 ? 0 : -1); 395 } 396 397 398 /* 399 * SOCKS5 connection initiation, based on RFC 1928 400 * Default DNS resolution over SOCKS5 401 */ 402 int 403 fetch_socks5_init(conn_t *conn, const char *host, int port, int verbose) 404 { 405 /* 406 * Size is based on largest packet prefix (4 bytes) + 407 * Largest FQDN (256) + one byte size (1) + 408 * Port (2) 409 */ 410 unsigned char buf[BUFF_SIZE]; 411 unsigned char *ptr; 412 int ret = 1; 413 414 if (verbose) 415 fetch_info("Initializing SOCKS5 connection: %s:%d", host, port); 416 417 /* Connection initialization */ 418 ptr = buf; 419 *ptr++ = SOCKS_VERSION_5; 420 *ptr++ = SOCKS_CONNECTION; 421 *ptr++ = SOCKS_RSV; 422 423 if (fetch_write(conn, buf, 3) != 3) { 424 ret = SOCKS5_ERR_SELECTION; 425 goto fail; 426 } 427 428 /* Verify response from SOCKS5 server */ 429 if (fetch_read(conn, buf, 2) != 2) { 430 ret = SOCKS5_ERR_READ_METHOD; 431 goto fail; 432 } 433 434 ptr = buf; 435 if (ptr[0] != SOCKS_VERSION_5) { 436 ret = SOCKS5_ERR_VER5_ONLY; 437 goto fail; 438 } 439 if (ptr[1] == SOCKS_NOMETHODS) { 440 ret = SOCKS5_ERR_NOMETHODS; 441 goto fail; 442 } 443 else if (ptr[1] != SOCKS5_NOTIMPLEMENTED) { 444 ret = SOCKS5_ERR_NOTIMPLEMENTED; 445 goto fail; 446 } 447 448 /* Send Request */ 449 *ptr++ = SOCKS_VERSION_5; 450 *ptr++ = SOCKS_CONNECTION; 451 *ptr++ = SOCKS_RSV; 452 /* Encode all targets as a hostname to avoid DNS leaks */ 453 *ptr++ = SOCKS_ATYP_DOMAINNAME; 454 if (strlen(host) > FQDN_SIZE) { 455 ret = SOCKS5_ERR_HOSTNAME_SIZE; 456 goto fail; 457 } 458 *ptr++ = strlen(host); 459 memcpy(ptr, host, strlen(host)); 460 ptr = ptr + strlen(host); 461 462 port = htons(port); 463 *ptr++ = port & 0x00ff; 464 *ptr++ = (port & 0xff00) >> 8; 465 466 if (fetch_write(conn, buf, ptr - buf) != ptr - buf) { 467 ret = SOCKS5_ERR_REQUEST; 468 goto fail; 469 } 470 471 /* BND.ADDR is variable length, read the largest on non-blocking socket */ 472 if (!fetch_read(conn, buf, BUFF_SIZE)) { 473 ret = SOCKS5_ERR_REPLY; 474 goto fail; 475 } 476 477 ptr = buf; 478 if (*ptr++ != SOCKS_VERSION_5) { 479 ret = SOCKS5_ERR_NON_VER5_RESP; 480 goto fail; 481 } 482 483 switch(*ptr++) { 484 case SOCKS_SUCCESS: 485 break; 486 case SOCKS_GENERAL_FAILURE: 487 ret = SOCKS5_ERR_GENERAL; 488 goto fail; 489 case SOCKS_CONNECTION_NOT_ALLOWED: 490 ret = SOCKS5_ERR_NOT_ALLOWED; 491 goto fail; 492 case SOCKS_NETWORK_UNREACHABLE: 493 ret = SOCKS5_ERR_NET_UNREACHABLE; 494 goto fail; 495 case SOCKS_HOST_UNREACHABLE: 496 ret = SOCKS5_ERR_HOST_UNREACHABLE; 497 goto fail; 498 case SOCKS_CONNECTION_REFUSED: 499 ret = SOCKS5_ERR_CONN_REFUSED; 500 goto fail; 501 case SOCKS_TTL_EXPIRED: 502 ret = SOCKS5_ERR_TTL_EXPIRED; 503 goto fail; 504 case SOCKS_COMMAND_NOT_SUPPORTED: 505 ret = SOCKS5_ERR_COM_UNSUPPORTED; 506 goto fail; 507 case SOCKS_ADDRESS_NOT_SUPPORTED: 508 ret = SOCKS5_ERR_ADDR_UNSUPPORTED; 509 goto fail; 510 default: 511 ret = SOCKS5_ERR_UNSPECIFIED; 512 goto fail; 513 } 514 515 return (ret); 516 517 fail: 518 socks5_seterr(ret); 519 return (0); 520 } 521 522 /* 523 * Perform SOCKS5 initialization 524 */ 525 int 526 fetch_socks5_getenv(char **host, int *port) 527 { 528 char *socks5env, *endptr, *ext; 529 const char *portDelim; 530 size_t slen; 531 532 portDelim = ":"; 533 if ((socks5env = getenv("SOCKS5_PROXY")) == NULL || *socks5env == '\0') { 534 *host = NULL; 535 *port = -1; 536 return (-1); 537 } 538 539 /* 540 * IPv6 addresses begin and end in brackets. Set the port delimiter 541 * accordingly and search for it so we can do appropriate validation. 542 */ 543 if (socks5env[0] == '[') 544 portDelim = "]:"; 545 546 slen = strlen(socks5env); 547 ext = strstr(socks5env, portDelim); 548 if (socks5env[0] == '[') { 549 if (socks5env[slen - 1] == ']') { 550 *host = strndup(socks5env, slen); 551 } else if (ext != NULL) { 552 *host = strndup(socks5env, ext - socks5env + 1); 553 } else { 554 socks5_seterr(SOCKS5_ERR_BAD_PROXY_FORMAT); 555 return (0); 556 } 557 } else { 558 *host = strndup(socks5env, ext - socks5env); 559 } 560 561 if (*host == NULL) { 562 fprintf(stderr, "Failure to allocate memory, exiting.\n"); 563 return (-1); 564 } 565 if (ext == NULL) { 566 *port = 1080; /* Default port as defined in RFC1928 */ 567 } else { 568 ext += strlen(portDelim); 569 errno = 0; 570 *port = strtoimax(ext, (char **)&endptr, 10); 571 if (*endptr != '\0' || errno != 0 || *port < 0 || 572 *port > 65535) { 573 free(*host); 574 *host = NULL; 575 socks5_seterr(SOCKS5_ERR_BAD_PORT); 576 return (0); 577 } 578 } 579 580 return (2); 581 } 582 583 584 /* 585 * Establish a TCP connection to the specified port on the specified host. 586 */ 587 conn_t * 588 fetch_connect(const char *host, int port, int af, int verbose) 589 { 590 struct addrinfo *cais = NULL, *sais = NULL, *cai, *sai; 591 const char *bindaddr; 592 conn_t *conn = NULL; 593 int err = 0, sd = -1; 594 char *sockshost; 595 int socksport; 596 597 DEBUGF("---> %s:%d\n", host, port); 598 599 /* 600 * Check if SOCKS5_PROXY env variable is set. fetch_socks5_getenv 601 * will either set sockshost = NULL or allocate memory in all cases. 602 */ 603 sockshost = NULL; 604 if (!fetch_socks5_getenv(&sockshost, &socksport)) 605 goto fail; 606 607 /* Not using SOCKS5 proxy */ 608 if (sockshost == NULL) { 609 /* resolve server address */ 610 if (verbose) 611 fetch_info("resolving server address: %s:%d", host, 612 port); 613 if ((sais = fetch_resolve(host, port, af)) == NULL) 614 goto fail; 615 616 /* resolve client address */ 617 bindaddr = getenv("FETCH_BIND_ADDRESS"); 618 if (bindaddr != NULL && *bindaddr != '\0') { 619 if (verbose) 620 fetch_info("resolving client address: %s", 621 bindaddr); 622 if ((cais = fetch_resolve(bindaddr, 0, af)) == NULL) 623 goto fail; 624 } 625 } else { 626 /* resolve socks5 proxy address */ 627 if (verbose) 628 fetch_info("resolving SOCKS5 server address: %s:%d", 629 sockshost, socksport); 630 if ((sais = fetch_resolve(sockshost, socksport, af)) == NULL) { 631 socks5_seterr(SOCKS5_ERR_BAD_HOST); 632 goto fail; 633 } 634 } 635 636 /* try each server address in turn */ 637 for (err = 0, sai = sais; sai != NULL; sai = sai->ai_next) { 638 /* open socket */ 639 if ((sd = socket(sai->ai_family, SOCK_STREAM, 0)) < 0) 640 goto syserr; 641 /* attempt to bind to client address */ 642 for (err = 0, cai = cais; cai != NULL; cai = cai->ai_next) { 643 if (cai->ai_family != sai->ai_family) 644 continue; 645 if ((err = bind(sd, cai->ai_addr, cai->ai_addrlen)) == 0) 646 break; 647 } 648 if (err != 0) { 649 if (verbose) 650 fetch_info("failed to bind to %s", bindaddr); 651 goto syserr; 652 } 653 /* attempt to connect to server address */ 654 if ((err = connect(sd, sai->ai_addr, sai->ai_addrlen)) == 0) 655 break; 656 /* clean up before next attempt */ 657 close(sd); 658 sd = -1; 659 } 660 if (err != 0) { 661 if (verbose && sockshost == NULL) { 662 fetch_info("failed to connect to %s:%d", host, port); 663 goto syserr; 664 } else if (sockshost != NULL) { 665 if (verbose) 666 fetch_info( 667 "failed to connect to SOCKS5 server %s:%d", 668 sockshost, socksport); 669 socks5_seterr(SOCKS5_ERR_CONN_REFUSED); 670 goto fail; 671 } 672 goto syserr; 673 } 674 675 if ((conn = fetch_reopen(sd)) == NULL) 676 goto syserr; 677 678 if (sockshost) 679 if (!fetch_socks5_init(conn, host, port, verbose)) 680 goto fail; 681 free(sockshost); 682 if (cais != NULL) 683 freeaddrinfo(cais); 684 if (sais != NULL) 685 freeaddrinfo(sais); 686 return (conn); 687 syserr: 688 fetch_syserr(); 689 fail: 690 free(sockshost); 691 /* Fully close if it was opened; otherwise just don't leak the fd. */ 692 if (conn != NULL) 693 fetch_close(conn); 694 else if (sd >= 0) 695 close(sd); 696 if (cais != NULL) 697 freeaddrinfo(cais); 698 if (sais != NULL) 699 freeaddrinfo(sais); 700 return (NULL); 701 } 702 703 #ifdef WITH_SSL 704 /* 705 * Convert characters A-Z to lowercase (intentionally avoid any locale 706 * specific conversions). 707 */ 708 static char 709 fetch_ssl_tolower(char in) 710 { 711 if (in >= 'A' && in <= 'Z') 712 return (in + 32); 713 else 714 return (in); 715 } 716 717 /* 718 * isalpha implementation that intentionally avoids any locale specific 719 * conversions. 720 */ 721 static int 722 fetch_ssl_isalpha(char in) 723 { 724 return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z')); 725 } 726 727 /* 728 * Check if passed hostnames a and b are equal. 729 */ 730 static int 731 fetch_ssl_hname_equal(const char *a, size_t alen, const char *b, 732 size_t blen) 733 { 734 size_t i; 735 736 if (alen != blen) 737 return (0); 738 for (i = 0; i < alen; ++i) { 739 if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i])) 740 return (0); 741 } 742 return (1); 743 } 744 745 /* 746 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9 747 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha- 748 * numeric characters. Double hyphens (like they're found in IDN a-labels 749 * 'xn--') are not allowed. Empty labels are invalid. 750 */ 751 static int 752 fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok) 753 { 754 size_t i; 755 756 if (!len || l[0] == '-' || l[len-1] == '-') 757 return (0); 758 for (i = 0; i < len; ++i) { 759 if (!isdigit(l[i]) && 760 !fetch_ssl_isalpha(l[i]) && 761 !(l[i] == '*' && wcok) && 762 !(l[i] == '-' && l[i - 1] != '-')) 763 return (0); 764 } 765 return (1); 766 } 767 768 /* 769 * Check if host name consists only of numbers. This might indicate an IP 770 * address, which is not a good idea for CN wildcard comparison. 771 */ 772 static int 773 fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len) 774 { 775 size_t i; 776 777 for (i = 0; i < len; ++i) { 778 if (!((hostname[i] >= '0' && hostname[i] <= '9') || 779 hostname[i] == '.')) 780 return (0); 781 } 782 return (1); 783 } 784 785 /* 786 * Check if the host name h passed matches the pattern passed in m which 787 * is usually part of subjectAltName or CN of a certificate presented to 788 * the client. This includes wildcard matching. The algorithm is based on 789 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280. 790 */ 791 static int 792 fetch_ssl_hname_match(const char *h, size_t hlen, const char *m, 793 size_t mlen) 794 { 795 int delta, hdotidx, mdot1idx, wcidx; 796 const char *hdot, *mdot1, *mdot2; 797 const char *wc; /* wildcard */ 798 799 if (!(h && *h && m && *m)) 800 return (0); 801 if ((wc = strnstr(m, "*", mlen)) == NULL) 802 return (fetch_ssl_hname_equal(h, hlen, m, mlen)); 803 wcidx = wc - m; 804 /* hostname should not be just dots and numbers */ 805 if (fetch_ssl_hname_is_only_numbers(h, hlen)) 806 return (0); 807 /* only one wildcard allowed in pattern */ 808 if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL) 809 return (0); 810 /* 811 * there must be at least two more domain labels and 812 * wildcard has to be in the leftmost label (RFC6125) 813 */ 814 mdot1 = strnstr(m, ".", mlen); 815 if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4) 816 return (0); 817 mdot1idx = mdot1 - m; 818 mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1); 819 if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2) 820 return (0); 821 /* hostname must contain a dot and not be the 1st char */ 822 hdot = strnstr(h, ".", hlen); 823 if (hdot == NULL || hdot == h) 824 return (0); 825 hdotidx = hdot - h; 826 /* 827 * host part of hostname must be at least as long as 828 * pattern it's supposed to match 829 */ 830 if (hdotidx < mdot1idx) 831 return (0); 832 /* 833 * don't allow wildcards in non-traditional domain names 834 * (IDN, A-label, U-label...) 835 */ 836 if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) || 837 !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1)) 838 return (0); 839 /* match domain part (part after first dot) */ 840 if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1, 841 mlen - mdot1idx)) 842 return (0); 843 /* match part left of wildcard */ 844 if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx)) 845 return (0); 846 /* match part right of wildcard */ 847 delta = mdot1idx - wcidx - 1; 848 if (!fetch_ssl_hname_equal(hdot - delta, delta, 849 mdot1 - delta, delta)) 850 return (0); 851 /* all tests succeeded, it's a match */ 852 return (1); 853 } 854 855 /* 856 * Get numeric host address info - returns NULL if host was not an IP 857 * address. The caller is responsible for deallocation using 858 * freeaddrinfo(3). 859 */ 860 static struct addrinfo * 861 fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len) 862 { 863 struct addrinfo hints, *res; 864 char *host; 865 866 host = (char *)malloc(len + 1); 867 memcpy(host, hostname, len); 868 host[len] = '\0'; 869 memset(&hints, 0, sizeof(hints)); 870 hints.ai_family = PF_UNSPEC; 871 hints.ai_socktype = SOCK_STREAM; 872 hints.ai_protocol = 0; 873 hints.ai_flags = AI_NUMERICHOST; 874 /* port is not relevant for this purpose */ 875 if (getaddrinfo(host, "443", &hints, &res) != 0) 876 res = NULL; 877 free(host); 878 return res; 879 } 880 881 /* 882 * Compare ip address in addrinfo with address passes. 883 */ 884 static int 885 fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost, 886 size_t rhostlen) 887 { 888 const void *left; 889 890 if (lhost->ai_family == AF_INET && rhostlen == 4) { 891 left = (void *)&((struct sockaddr_in*)(void *) 892 lhost->ai_addr)->sin_addr.s_addr; 893 #ifdef INET6 894 } else if (lhost->ai_family == AF_INET6 && rhostlen == 16) { 895 left = (void *)&((struct sockaddr_in6 *)(void *) 896 lhost->ai_addr)->sin6_addr; 897 #endif 898 } else 899 return (0); 900 return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0); 901 } 902 903 /* 904 * Compare ip address in addrinfo with host passed. If host is not an IP 905 * address, comparison will fail. 906 */ 907 static int 908 fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r, 909 size_t rlen) 910 { 911 struct addrinfo *raddr; 912 int ret; 913 char *rip; 914 915 ret = 0; 916 if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL) 917 return 0; /* not a numeric host */ 918 919 if (laddr->ai_family == raddr->ai_family) { 920 if (laddr->ai_family == AF_INET) { 921 rip = (char *)&((struct sockaddr_in *)(void *) 922 raddr->ai_addr)->sin_addr.s_addr; 923 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4); 924 #ifdef INET6 925 } else if (laddr->ai_family == AF_INET6) { 926 rip = (char *)&((struct sockaddr_in6 *)(void *) 927 raddr->ai_addr)->sin6_addr; 928 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16); 929 #endif 930 } 931 932 } 933 freeaddrinfo(raddr); 934 return (ret); 935 } 936 937 /* 938 * Verify server certificate by subjectAltName. 939 */ 940 static int 941 fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames, 942 const char *host, struct addrinfo *ip) 943 { 944 const GENERAL_NAME *name; 945 size_t nslen; 946 int i; 947 const char *ns; 948 949 for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) { 950 #if OPENSSL_VERSION_NUMBER < 0x10000000L 951 /* 952 * This is a workaround, since the following line causes 953 * alignment issues in clang: 954 * name = sk_GENERAL_NAME_value(altnames, i); 955 * OpenSSL explicitly warns not to use those macros 956 * directly, but there isn't much choice (and there 957 * shouldn't be any ill side effects) 958 */ 959 name = (GENERAL_NAME *)SKM_sk_value(void, altnames, i); 960 #else 961 name = sk_GENERAL_NAME_value(altnames, i); 962 #endif 963 #if OPENSSL_VERSION_NUMBER < 0x10100000L 964 ns = (const char *)ASN1_STRING_data(name->d.ia5); 965 #else 966 ns = (const char *)ASN1_STRING_get0_data(name->d.ia5); 967 #endif 968 nslen = (size_t)ASN1_STRING_length(name->d.ia5); 969 970 if (name->type == GEN_DNS && ip == NULL && 971 fetch_ssl_hname_match(host, strlen(host), ns, nslen)) 972 return (1); 973 else if (name->type == GEN_IPADD && ip != NULL && 974 fetch_ssl_ipaddr_match_bin(ip, ns, nslen)) 975 return (1); 976 } 977 return (0); 978 } 979 980 /* 981 * Verify server certificate by CN. 982 */ 983 static int 984 fetch_ssl_verify_cn(X509_NAME *subject, const char *host, 985 struct addrinfo *ip) 986 { 987 ASN1_STRING *namedata; 988 X509_NAME_ENTRY *nameentry; 989 int cnlen, lastpos, loc, ret; 990 unsigned char *cn; 991 992 ret = 0; 993 lastpos = -1; 994 loc = -1; 995 cn = NULL; 996 /* get most specific CN (last entry in list) and compare */ 997 while ((lastpos = X509_NAME_get_index_by_NID(subject, 998 NID_commonName, lastpos)) != -1) 999 loc = lastpos; 1000 1001 if (loc > -1) { 1002 nameentry = X509_NAME_get_entry(subject, loc); 1003 namedata = X509_NAME_ENTRY_get_data(nameentry); 1004 cnlen = ASN1_STRING_to_UTF8(&cn, namedata); 1005 if (ip == NULL && 1006 fetch_ssl_hname_match(host, strlen(host), cn, cnlen)) 1007 ret = 1; 1008 else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen)) 1009 ret = 1; 1010 OPENSSL_free(cn); 1011 } 1012 return (ret); 1013 } 1014 1015 /* 1016 * Verify that server certificate subjectAltName/CN matches 1017 * hostname. First check, if there are alternative subject names. If yes, 1018 * those have to match. Only if those don't exist it falls back to 1019 * checking the subject's CN. 1020 */ 1021 static int 1022 fetch_ssl_verify_hname(X509 *cert, const char *host) 1023 { 1024 struct addrinfo *ip; 1025 STACK_OF(GENERAL_NAME) *altnames; 1026 X509_NAME *subject; 1027 int ret; 1028 1029 ret = 0; 1030 ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host)); 1031 altnames = X509_get_ext_d2i(cert, NID_subject_alt_name, 1032 NULL, NULL); 1033 1034 if (altnames != NULL) { 1035 ret = fetch_ssl_verify_altname(altnames, host, ip); 1036 } else { 1037 subject = X509_get_subject_name(cert); 1038 if (subject != NULL) 1039 ret = fetch_ssl_verify_cn(subject, host, ip); 1040 } 1041 1042 if (ip != NULL) 1043 freeaddrinfo(ip); 1044 if (altnames != NULL) 1045 GENERAL_NAMES_free(altnames); 1046 return (ret); 1047 } 1048 1049 /* 1050 * Configure transport security layer based on environment. 1051 */ 1052 static void 1053 fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose) 1054 { 1055 long ssl_ctx_options; 1056 1057 ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_SSLv3 | SSL_OP_NO_TICKET; 1058 if (getenv("SSL_NO_TLS1") != NULL) 1059 ssl_ctx_options |= SSL_OP_NO_TLSv1; 1060 if (getenv("SSL_NO_TLS1_1") != NULL) 1061 ssl_ctx_options |= SSL_OP_NO_TLSv1_1; 1062 if (getenv("SSL_NO_TLS1_2") != NULL) 1063 ssl_ctx_options |= SSL_OP_NO_TLSv1_2; 1064 if (verbose) 1065 fetch_info("SSL options: %lx", ssl_ctx_options); 1066 SSL_CTX_set_options(ctx, ssl_ctx_options); 1067 } 1068 1069 1070 /* 1071 * Configure peer verification based on environment. 1072 */ 1073 #define LOCAL_CERT_FILE _PATH_LOCALBASE "/etc/ssl/cert.pem" 1074 #define BASE_CERT_FILE "/etc/ssl/cert.pem" 1075 static int 1076 fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose) 1077 { 1078 X509_LOOKUP *crl_lookup; 1079 X509_STORE *crl_store; 1080 const char *ca_cert_file, *ca_cert_path, *crl_file; 1081 1082 if (getenv("SSL_NO_VERIFY_PEER") == NULL) { 1083 ca_cert_file = getenv("SSL_CA_CERT_FILE"); 1084 if (ca_cert_file == NULL && 1085 access(LOCAL_CERT_FILE, R_OK) == 0) 1086 ca_cert_file = LOCAL_CERT_FILE; 1087 if (ca_cert_file == NULL && 1088 access(BASE_CERT_FILE, R_OK) == 0) 1089 ca_cert_file = BASE_CERT_FILE; 1090 ca_cert_path = getenv("SSL_CA_CERT_PATH"); 1091 if (verbose) { 1092 fetch_info("Peer verification enabled"); 1093 if (ca_cert_file != NULL) 1094 fetch_info("Using CA cert file: %s", 1095 ca_cert_file); 1096 if (ca_cert_path != NULL) 1097 fetch_info("Using CA cert path: %s", 1098 ca_cert_path); 1099 if (ca_cert_file == NULL && ca_cert_path == NULL) 1100 fetch_info("Using OpenSSL default " 1101 "CA cert file and path"); 1102 } 1103 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, 1104 fetch_ssl_cb_verify_crt); 1105 if (ca_cert_file != NULL || ca_cert_path != NULL) 1106 SSL_CTX_load_verify_locations(ctx, ca_cert_file, 1107 ca_cert_path); 1108 else 1109 SSL_CTX_set_default_verify_paths(ctx); 1110 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) { 1111 if (verbose) 1112 fetch_info("Using CRL file: %s", crl_file); 1113 crl_store = SSL_CTX_get_cert_store(ctx); 1114 crl_lookup = X509_STORE_add_lookup(crl_store, 1115 X509_LOOKUP_file()); 1116 if (crl_lookup == NULL || 1117 !X509_load_crl_file(crl_lookup, crl_file, 1118 X509_FILETYPE_PEM)) { 1119 fprintf(stderr, 1120 "Could not load CRL file %s\n", 1121 crl_file); 1122 return (0); 1123 } 1124 X509_STORE_set_flags(crl_store, 1125 X509_V_FLAG_CRL_CHECK | 1126 X509_V_FLAG_CRL_CHECK_ALL); 1127 } 1128 } 1129 return (1); 1130 } 1131 1132 /* 1133 * Configure client certificate based on environment. 1134 */ 1135 static int 1136 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose) 1137 { 1138 const char *client_cert_file, *client_key_file; 1139 1140 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) { 1141 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ? 1142 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file; 1143 if (verbose) { 1144 fetch_info("Using client cert file: %s", 1145 client_cert_file); 1146 fetch_info("Using client key file: %s", 1147 client_key_file); 1148 } 1149 if (SSL_CTX_use_certificate_chain_file(ctx, 1150 client_cert_file) != 1) { 1151 fprintf(stderr, 1152 "Could not load client certificate %s\n", 1153 client_cert_file); 1154 return (0); 1155 } 1156 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file, 1157 SSL_FILETYPE_PEM) != 1) { 1158 fprintf(stderr, 1159 "Could not load client key %s\n", 1160 client_key_file); 1161 return (0); 1162 } 1163 } 1164 return (1); 1165 } 1166 1167 /* 1168 * Callback for SSL certificate verification, this is called on server 1169 * cert verification. It takes no decision, but informs the user in case 1170 * verification failed. 1171 */ 1172 int 1173 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx) 1174 { 1175 X509 *crt; 1176 X509_NAME *name; 1177 char *str; 1178 1179 str = NULL; 1180 if (!verified) { 1181 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL && 1182 (name = X509_get_subject_name(crt)) != NULL) 1183 str = X509_NAME_oneline(name, 0, 0); 1184 fprintf(stderr, "Certificate verification failed for %s\n", 1185 str != NULL ? str : "no relevant certificate"); 1186 OPENSSL_free(str); 1187 } 1188 return (verified); 1189 } 1190 1191 #endif 1192 1193 /* 1194 * Enable SSL on a connection. 1195 */ 1196 int 1197 fetch_ssl(conn_t *conn, const struct url *URL, int verbose) 1198 { 1199 #ifdef WITH_SSL 1200 int ret, ssl_err; 1201 X509_NAME *name; 1202 char *str; 1203 1204 /* Init the SSL library and context */ 1205 if (!SSL_library_init()){ 1206 fprintf(stderr, "SSL library init failed\n"); 1207 return (-1); 1208 } 1209 1210 SSL_load_error_strings(); 1211 1212 conn->ssl_meth = SSLv23_client_method(); 1213 conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth); 1214 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY); 1215 1216 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose); 1217 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose)) 1218 return (-1); 1219 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose)) 1220 return (-1); 1221 1222 conn->ssl = SSL_new(conn->ssl_ctx); 1223 if (conn->ssl == NULL) { 1224 fprintf(stderr, "SSL context creation failed\n"); 1225 return (-1); 1226 } 1227 SSL_set_fd(conn->ssl, conn->sd); 1228 1229 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) 1230 if (!SSL_set_tlsext_host_name(conn->ssl, 1231 __DECONST(struct url *, URL)->host)) { 1232 fprintf(stderr, 1233 "TLS server name indication extension failed for host %s\n", 1234 URL->host); 1235 return (-1); 1236 } 1237 #endif 1238 while ((ret = SSL_connect(conn->ssl)) == -1) { 1239 ssl_err = SSL_get_error(conn->ssl, ret); 1240 if (ssl_err != SSL_ERROR_WANT_READ && 1241 ssl_err != SSL_ERROR_WANT_WRITE) { 1242 ERR_print_errors_fp(stderr); 1243 return (-1); 1244 } 1245 } 1246 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl); 1247 1248 if (conn->ssl_cert == NULL) { 1249 fprintf(stderr, "No server SSL certificate\n"); 1250 return (-1); 1251 } 1252 1253 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) { 1254 if (verbose) 1255 fetch_info("Verify hostname"); 1256 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) { 1257 fprintf(stderr, 1258 "SSL certificate subject doesn't match host %s\n", 1259 URL->host); 1260 return (-1); 1261 } 1262 } 1263 1264 if (verbose) { 1265 fetch_info("%s connection established using %s", 1266 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl)); 1267 name = X509_get_subject_name(conn->ssl_cert); 1268 str = X509_NAME_oneline(name, 0, 0); 1269 fetch_info("Certificate subject: %s", str); 1270 OPENSSL_free(str); 1271 name = X509_get_issuer_name(conn->ssl_cert); 1272 str = X509_NAME_oneline(name, 0, 0); 1273 fetch_info("Certificate issuer: %s", str); 1274 OPENSSL_free(str); 1275 } 1276 1277 return (0); 1278 #else 1279 (void)conn; 1280 (void)verbose; 1281 (void)URL; 1282 fprintf(stderr, "SSL support disabled\n"); 1283 return (-1); 1284 #endif 1285 } 1286 1287 #define FETCH_READ_WAIT -2 1288 #define FETCH_READ_ERROR -1 1289 #define FETCH_READ_DONE 0 1290 1291 #ifdef WITH_SSL 1292 static ssize_t 1293 fetch_ssl_read(SSL *ssl, char *buf, size_t len) 1294 { 1295 ssize_t rlen; 1296 int ssl_err; 1297 1298 rlen = SSL_read(ssl, buf, len); 1299 if (rlen < 0) { 1300 ssl_err = SSL_get_error(ssl, rlen); 1301 if (ssl_err == SSL_ERROR_WANT_READ || 1302 ssl_err == SSL_ERROR_WANT_WRITE) { 1303 return (FETCH_READ_WAIT); 1304 } else { 1305 ERR_print_errors_fp(stderr); 1306 return (FETCH_READ_ERROR); 1307 } 1308 } 1309 return (rlen); 1310 } 1311 #endif 1312 1313 static ssize_t 1314 fetch_socket_read(int sd, char *buf, size_t len) 1315 { 1316 ssize_t rlen; 1317 1318 rlen = read(sd, buf, len); 1319 if (rlen < 0) { 1320 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls)) 1321 return (FETCH_READ_WAIT); 1322 else 1323 return (FETCH_READ_ERROR); 1324 } 1325 return (rlen); 1326 } 1327 1328 /* 1329 * Read a character from a connection w/ timeout 1330 */ 1331 ssize_t 1332 fetch_read(conn_t *conn, char *buf, size_t len) 1333 { 1334 struct timeval now, timeout, delta; 1335 struct pollfd pfd; 1336 ssize_t rlen; 1337 int deltams; 1338 1339 if (fetchTimeout > 0) { 1340 gettimeofday(&timeout, NULL); 1341 timeout.tv_sec += fetchTimeout; 1342 } 1343 1344 deltams = INFTIM; 1345 memset(&pfd, 0, sizeof pfd); 1346 pfd.fd = conn->sd; 1347 pfd.events = POLLIN | POLLERR; 1348 1349 for (;;) { 1350 /* 1351 * The socket is non-blocking. Instead of the canonical 1352 * poll() -> read(), we do the following: 1353 * 1354 * 1) call read() or SSL_read(). 1355 * 2) if we received some data, return it. 1356 * 3) if an error occurred, return -1. 1357 * 4) if read() or SSL_read() signaled EOF, return. 1358 * 5) if we did not receive any data but we're not at EOF, 1359 * call poll(). 1360 * 1361 * In the SSL case, this is necessary because if we 1362 * receive a close notification, we have to call 1363 * SSL_read() one additional time after we've read 1364 * everything we received. 1365 * 1366 * In the non-SSL case, it may improve performance (very 1367 * slightly) when reading small amounts of data. 1368 */ 1369 #ifdef WITH_SSL 1370 if (conn->ssl != NULL) 1371 rlen = fetch_ssl_read(conn->ssl, buf, len); 1372 else 1373 #endif 1374 rlen = fetch_socket_read(conn->sd, buf, len); 1375 if (rlen >= 0) { 1376 break; 1377 } else if (rlen == FETCH_READ_ERROR) { 1378 fetch_syserr(); 1379 return (-1); 1380 } 1381 // assert(rlen == FETCH_READ_WAIT); 1382 if (fetchTimeout > 0) { 1383 gettimeofday(&now, NULL); 1384 if (!timercmp(&timeout, &now, >)) { 1385 errno = ETIMEDOUT; 1386 fetch_syserr(); 1387 return (-1); 1388 } 1389 timersub(&timeout, &now, &delta); 1390 deltams = delta.tv_sec * 1000 + 1391 delta.tv_usec / 1000;; 1392 } 1393 errno = 0; 1394 pfd.revents = 0; 1395 if (poll(&pfd, 1, deltams) < 0) { 1396 if (errno == EINTR && fetchRestartCalls) 1397 continue; 1398 fetch_syserr(); 1399 return (-1); 1400 } 1401 } 1402 return (rlen); 1403 } 1404 1405 1406 /* 1407 * Read a line of text from a connection w/ timeout 1408 */ 1409 #define MIN_BUF_SIZE 1024 1410 1411 int 1412 fetch_getln(conn_t *conn) 1413 { 1414 char *tmp; 1415 size_t tmpsize; 1416 ssize_t len; 1417 char c; 1418 1419 if (conn->buf == NULL) { 1420 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) { 1421 errno = ENOMEM; 1422 return (-1); 1423 } 1424 conn->bufsize = MIN_BUF_SIZE; 1425 } 1426 1427 conn->buf[0] = '\0'; 1428 conn->buflen = 0; 1429 1430 do { 1431 len = fetch_read(conn, &c, 1); 1432 if (len == -1) 1433 return (-1); 1434 if (len == 0) 1435 break; 1436 conn->buf[conn->buflen++] = c; 1437 if (conn->buflen == conn->bufsize) { 1438 tmp = conn->buf; 1439 tmpsize = conn->bufsize * 2 + 1; 1440 if ((tmp = realloc(tmp, tmpsize)) == NULL) { 1441 errno = ENOMEM; 1442 return (-1); 1443 } 1444 conn->buf = tmp; 1445 conn->bufsize = tmpsize; 1446 } 1447 } while (c != '\n'); 1448 1449 conn->buf[conn->buflen] = '\0'; 1450 DEBUGF("<<< %s", conn->buf); 1451 return (0); 1452 } 1453 1454 1455 /* 1456 * Write to a connection w/ timeout 1457 */ 1458 ssize_t 1459 fetch_write(conn_t *conn, const char *buf, size_t len) 1460 { 1461 struct iovec iov; 1462 1463 iov.iov_base = __DECONST(char *, buf); 1464 iov.iov_len = len; 1465 return fetch_writev(conn, &iov, 1); 1466 } 1467 1468 /* 1469 * Write a vector to a connection w/ timeout 1470 * Note: can modify the iovec. 1471 */ 1472 ssize_t 1473 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt) 1474 { 1475 struct timeval now, timeout, delta; 1476 struct pollfd pfd; 1477 ssize_t wlen, total; 1478 int deltams; 1479 1480 memset(&pfd, 0, sizeof pfd); 1481 if (fetchTimeout) { 1482 pfd.fd = conn->sd; 1483 pfd.events = POLLOUT | POLLERR; 1484 gettimeofday(&timeout, NULL); 1485 timeout.tv_sec += fetchTimeout; 1486 } 1487 1488 total = 0; 1489 while (iovcnt > 0) { 1490 while (fetchTimeout && pfd.revents == 0) { 1491 gettimeofday(&now, NULL); 1492 if (!timercmp(&timeout, &now, >)) { 1493 errno = ETIMEDOUT; 1494 fetch_syserr(); 1495 return (-1); 1496 } 1497 timersub(&timeout, &now, &delta); 1498 deltams = delta.tv_sec * 1000 + 1499 delta.tv_usec / 1000; 1500 errno = 0; 1501 pfd.revents = 0; 1502 if (poll(&pfd, 1, deltams) < 0) { 1503 /* POSIX compliance */ 1504 if (errno == EAGAIN) 1505 continue; 1506 if (errno == EINTR && fetchRestartCalls) 1507 continue; 1508 return (-1); 1509 } 1510 } 1511 errno = 0; 1512 #ifdef WITH_SSL 1513 if (conn->ssl != NULL) 1514 wlen = SSL_write(conn->ssl, 1515 iov->iov_base, iov->iov_len); 1516 else 1517 #endif 1518 wlen = writev(conn->sd, iov, iovcnt); 1519 if (wlen == 0) { 1520 /* we consider a short write a failure */ 1521 /* XXX perhaps we shouldn't in the SSL case */ 1522 errno = EPIPE; 1523 fetch_syserr(); 1524 return (-1); 1525 } 1526 if (wlen < 0) { 1527 if (errno == EINTR && fetchRestartCalls) 1528 continue; 1529 return (-1); 1530 } 1531 total += wlen; 1532 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) { 1533 wlen -= iov->iov_len; 1534 iov++; 1535 iovcnt--; 1536 } 1537 if (iovcnt > 0) { 1538 iov->iov_len -= wlen; 1539 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen; 1540 } 1541 } 1542 return (total); 1543 } 1544 1545 1546 /* 1547 * Write a line of text to a connection w/ timeout 1548 */ 1549 int 1550 fetch_putln(conn_t *conn, const char *str, size_t len) 1551 { 1552 struct iovec iov[2]; 1553 int ret; 1554 1555 DEBUGF(">>> %s\n", str); 1556 iov[0].iov_base = __DECONST(char *, str); 1557 iov[0].iov_len = len; 1558 iov[1].iov_base = __DECONST(char *, ENDL); 1559 iov[1].iov_len = sizeof(ENDL); 1560 if (len == 0) 1561 ret = fetch_writev(conn, &iov[1], 1); 1562 else 1563 ret = fetch_writev(conn, iov, 2); 1564 if (ret == -1) 1565 return (-1); 1566 return (0); 1567 } 1568 1569 1570 /* 1571 * Close connection 1572 */ 1573 int 1574 fetch_close(conn_t *conn) 1575 { 1576 int ret; 1577 1578 if (--conn->ref > 0) 1579 return (0); 1580 #ifdef WITH_SSL 1581 if (conn->ssl) { 1582 SSL_shutdown(conn->ssl); 1583 SSL_set_connect_state(conn->ssl); 1584 SSL_free(conn->ssl); 1585 conn->ssl = NULL; 1586 } 1587 if (conn->ssl_ctx) { 1588 SSL_CTX_free(conn->ssl_ctx); 1589 conn->ssl_ctx = NULL; 1590 } 1591 if (conn->ssl_cert) { 1592 X509_free(conn->ssl_cert); 1593 conn->ssl_cert = NULL; 1594 } 1595 #endif 1596 ret = close(conn->sd); 1597 free(conn->buf); 1598 free(conn); 1599 return (ret); 1600 } 1601 1602 1603 /*** Directory-related utility functions *************************************/ 1604 1605 int 1606 fetch_add_entry(struct url_ent **p, int *size, int *len, 1607 const char *name, struct url_stat *us) 1608 { 1609 struct url_ent *tmp; 1610 1611 if (*p == NULL) { 1612 *size = 0; 1613 *len = 0; 1614 } 1615 1616 if (*len >= *size - 1) { 1617 tmp = reallocarray(*p, *size * 2 + 1, sizeof(**p)); 1618 if (tmp == NULL) { 1619 errno = ENOMEM; 1620 fetch_syserr(); 1621 return (-1); 1622 } 1623 *size = (*size * 2 + 1); 1624 *p = tmp; 1625 } 1626 1627 tmp = *p + *len; 1628 snprintf(tmp->name, PATH_MAX, "%s", name); 1629 memcpy(&tmp->stat, us, sizeof(*us)); 1630 1631 (*len)++; 1632 (++tmp)->name[0] = 0; 1633 1634 return (0); 1635 } 1636 1637 1638 /*** Authentication-related utility functions ********************************/ 1639 1640 static const char * 1641 fetch_read_word(FILE *f) 1642 { 1643 static char word[1024]; 1644 1645 if (fscanf(f, " %1023s ", word) != 1) 1646 return (NULL); 1647 return (word); 1648 } 1649 1650 static int 1651 fetch_netrc_open(void) 1652 { 1653 struct passwd *pwd; 1654 char fn[PATH_MAX]; 1655 const char *p; 1656 int fd, serrno; 1657 1658 if ((p = getenv("NETRC")) != NULL) { 1659 DEBUGF("NETRC=%s\n", p); 1660 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) { 1661 fetch_info("$NETRC specifies a file name " 1662 "longer than PATH_MAX"); 1663 return (-1); 1664 } 1665 } else { 1666 if ((p = getenv("HOME")) == NULL) { 1667 if ((pwd = getpwuid(getuid())) == NULL || 1668 (p = pwd->pw_dir) == NULL) 1669 return (-1); 1670 } 1671 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn)) 1672 return (-1); 1673 } 1674 1675 if ((fd = open(fn, O_RDONLY)) < 0) { 1676 serrno = errno; 1677 DEBUGF("%s: %s\n", fn, strerror(serrno)); 1678 errno = serrno; 1679 } 1680 return (fd); 1681 } 1682 1683 /* 1684 * Get authentication data for a URL from .netrc 1685 */ 1686 int 1687 fetch_netrc_auth(struct url *url) 1688 { 1689 const char *word; 1690 int serrno; 1691 FILE *f; 1692 1693 if (url->netrcfd < 0) 1694 url->netrcfd = fetch_netrc_open(); 1695 if (url->netrcfd < 0) 1696 return (-1); 1697 if ((f = fdopen(url->netrcfd, "r")) == NULL) { 1698 serrno = errno; 1699 DEBUGF("fdopen(netrcfd): %s", strerror(errno)); 1700 close(url->netrcfd); 1701 url->netrcfd = -1; 1702 errno = serrno; 1703 return (-1); 1704 } 1705 rewind(f); 1706 DEBUGF("searching netrc for %s\n", url->host); 1707 while ((word = fetch_read_word(f)) != NULL) { 1708 if (strcmp(word, "default") == 0) { 1709 DEBUGF("using default netrc settings\n"); 1710 break; 1711 } 1712 if (strcmp(word, "machine") == 0 && 1713 (word = fetch_read_word(f)) != NULL && 1714 strcasecmp(word, url->host) == 0) { 1715 DEBUGF("using netrc settings for %s\n", word); 1716 break; 1717 } 1718 } 1719 if (word == NULL) 1720 goto ferr; 1721 while ((word = fetch_read_word(f)) != NULL) { 1722 if (strcmp(word, "login") == 0) { 1723 if ((word = fetch_read_word(f)) == NULL) 1724 goto ferr; 1725 if (snprintf(url->user, sizeof(url->user), 1726 "%s", word) > (int)sizeof(url->user)) { 1727 fetch_info("login name in .netrc is too long"); 1728 url->user[0] = '\0'; 1729 } 1730 } else if (strcmp(word, "password") == 0) { 1731 if ((word = fetch_read_word(f)) == NULL) 1732 goto ferr; 1733 if (snprintf(url->pwd, sizeof(url->pwd), 1734 "%s", word) > (int)sizeof(url->pwd)) { 1735 fetch_info("password in .netrc is too long"); 1736 url->pwd[0] = '\0'; 1737 } 1738 } else if (strcmp(word, "account") == 0) { 1739 if ((word = fetch_read_word(f)) == NULL) 1740 goto ferr; 1741 /* XXX not supported! */ 1742 } else { 1743 break; 1744 } 1745 } 1746 fclose(f); 1747 url->netrcfd = -1; 1748 return (0); 1749 ferr: 1750 serrno = errno; 1751 fclose(f); 1752 url->netrcfd = -1; 1753 errno = serrno; 1754 return (-1); 1755 } 1756 1757 /* 1758 * The no_proxy environment variable specifies a set of domains for 1759 * which the proxy should not be consulted; the contents is a comma-, 1760 * or space-separated list of domain names. A single asterisk will 1761 * override all proxy variables and no transactions will be proxied 1762 * (for compatibility with lynx and curl, see the discussion at 1763 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>). 1764 */ 1765 int 1766 fetch_no_proxy_match(const char *host) 1767 { 1768 const char *no_proxy, *p, *q; 1769 size_t h_len, d_len; 1770 1771 if ((no_proxy = getenv("NO_PROXY")) == NULL && 1772 (no_proxy = getenv("no_proxy")) == NULL) 1773 return (0); 1774 1775 /* asterisk matches any hostname */ 1776 if (strcmp(no_proxy, "*") == 0) 1777 return (1); 1778 1779 h_len = strlen(host); 1780 p = no_proxy; 1781 do { 1782 /* position p at the beginning of a domain suffix */ 1783 while (*p == ',' || isspace((unsigned char)*p)) 1784 p++; 1785 1786 /* position q at the first separator character */ 1787 for (q = p; *q; ++q) 1788 if (*q == ',' || isspace((unsigned char)*q)) 1789 break; 1790 1791 d_len = q - p; 1792 if (d_len > 0 && h_len >= d_len && 1793 strncasecmp(host + h_len - d_len, 1794 p, d_len) == 0) { 1795 /* domain name matches */ 1796 return (1); 1797 } 1798 1799 p = q + 1; 1800 } while (*q); 1801 1802 return (0); 1803 } 1804