common.c
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 "bsd_compat.h" 33 34 #include <sys/param.h> 35 #include <sys/socket.h> 36 #include <sys/time.h> 37 #include <sys/uio.h> 38 39 #include <netinet/in.h> 40 41 #include <ctype.h> 42 #include <errno.h> 43 #include <fcntl.h> 44 #include <inttypes.h> 45 #include <netdb.h> 46 #include <paths.h> 47 #include <poll.h> 48 #include <pwd.h> 49 #include <stdarg.h> 50 #include <stdlib.h> 51 #include <stdio.h> 52 #include <string.h> 53 #include <unistd.h> 54 55 #ifdef WITH_SSL 56 #include <openssl/x509v3.h> 57 #endif 58 59 #include "fetch.h" 60 #include "common.h" 61 62 #ifndef INFTIM 63 #define INFTIM (-1) 64 #endif 65 66 /*** Local data **************************************************************/ 67 68 /* 69 * Error messages for resolver errors 70 */ 71 static struct fetcherr netdb_errlist[] = { 72 #ifdef EAI_ADDRFAMILY 73 { EAI_ADDRFAMILY, FETCH_RESOLV, "Address family for host not supported" }, 74 #endif 75 #ifdef EAI_NODATA 76 { EAI_NODATA, FETCH_RESOLV, "No address for host" }, 77 #endif 78 { EAI_AGAIN, FETCH_TEMP, "Transient resolver failure" }, 79 { EAI_FAIL, FETCH_RESOLV, "Non-recoverable resolver failure" }, 80 { EAI_NONAME, FETCH_RESOLV, "Host does not resolve" }, 81 { -1, FETCH_UNKNOWN, "Unknown resolver error" } 82 }; 83 84 /* 85 * SOCKS5 error enumerations 86 */ 87 enum SOCKS5_ERR { 88 /* Protocol errors */ 89 SOCKS5_ERR_SELECTION, 90 SOCKS5_ERR_READ_METHOD, 91 SOCKS5_ERR_VER5_ONLY, 92 SOCKS5_ERR_NOMETHODS, 93 SOCKS5_ERR_NOTIMPLEMENTED, 94 SOCKS5_ERR_HOSTNAME_SIZE, 95 SOCKS5_ERR_REQUEST, 96 SOCKS5_ERR_REPLY, 97 SOCKS5_ERR_NON_VER5_RESP, 98 SOCKS5_ERR_GENERAL, 99 SOCKS5_ERR_NOT_ALLOWED, 100 SOCKS5_ERR_NET_UNREACHABLE, 101 SOCKS5_ERR_HOST_UNREACHABLE, 102 SOCKS5_ERR_CONN_REFUSED, 103 SOCKS5_ERR_TTL_EXPIRED, 104 SOCKS5_ERR_COM_UNSUPPORTED, 105 SOCKS5_ERR_ADDR_UNSUPPORTED, 106 SOCKS5_ERR_UNSPECIFIED, 107 /* Configuration errors */ 108 SOCKS5_ERR_BAD_HOST, 109 SOCKS5_ERR_BAD_PROXY_FORMAT, 110 SOCKS5_ERR_BAD_PORT 111 }; 112 113 /* 114 * Error messages for SOCKS5 errors 115 */ 116 static struct fetcherr socks5_errlist[] = { 117 /* SOCKS5 protocol errors */ 118 { SOCKS5_ERR_SELECTION, FETCH_ABORT, "SOCKS5: Failed to send selection method" }, 119 { SOCKS5_ERR_READ_METHOD, FETCH_ABORT, "SOCKS5: Failed to read method" }, 120 { SOCKS5_ERR_VER5_ONLY, FETCH_PROTO, "SOCKS5: Only version 5 is implemented" }, 121 { SOCKS5_ERR_NOMETHODS, FETCH_PROTO, "SOCKS5: No acceptable methods" }, 122 { SOCKS5_ERR_NOTIMPLEMENTED, FETCH_PROTO, "SOCKS5: Method currently not implemented" }, 123 { SOCKS5_ERR_HOSTNAME_SIZE, FETCH_PROTO, "SOCKS5: Hostname size is above 256 bytes" }, 124 { SOCKS5_ERR_REQUEST, FETCH_PROTO, "SOCKS5: Failed to request" }, 125 { SOCKS5_ERR_REPLY, FETCH_PROTO, "SOCKS5: Failed to receive reply" }, 126 { SOCKS5_ERR_NON_VER5_RESP, FETCH_PROTO, "SOCKS5: Server responded with a non-version 5 response" }, 127 { SOCKS5_ERR_GENERAL, FETCH_ABORT, "SOCKS5: General server failure" }, 128 { SOCKS5_ERR_NOT_ALLOWED, FETCH_AUTH, "SOCKS5: Connection not allowed by ruleset" }, 129 { SOCKS5_ERR_NET_UNREACHABLE, FETCH_NETWORK, "SOCKS5: Network unreachable" }, 130 { SOCKS5_ERR_HOST_UNREACHABLE, FETCH_ABORT, "SOCKS5: Host unreachable" }, 131 { SOCKS5_ERR_CONN_REFUSED, FETCH_ABORT, "SOCKS5: Connection refused" }, 132 { SOCKS5_ERR_TTL_EXPIRED, FETCH_TIMEOUT, "SOCKS5: TTL expired" }, 133 { SOCKS5_ERR_COM_UNSUPPORTED, FETCH_PROTO, "SOCKS5: Command not supported" }, 134 { SOCKS5_ERR_ADDR_UNSUPPORTED, FETCH_ABORT, "SOCKS5: Address type not supported" }, 135 { SOCKS5_ERR_UNSPECIFIED, FETCH_UNKNOWN, "SOCKS5: Unspecified error" }, 136 /* Configuration error */ 137 { SOCKS5_ERR_BAD_HOST, FETCH_ABORT, "SOCKS5: Bad proxy host" }, 138 { SOCKS5_ERR_BAD_PROXY_FORMAT, FETCH_ABORT, "SOCKS5: Bad proxy format" }, 139 { SOCKS5_ERR_BAD_PORT, FETCH_ABORT, "SOCKS5: Bad port" } 140 }; 141 142 /* End-of-Line */ 143 static const char ENDL[2] = { '\r', '\n' }; 144 145 146 /*** Error-reporting functions ***********************************************/ 147 148 /* 149 * Map error code to string 150 */ 151 static struct fetcherr * 152 fetch_finderr(struct fetcherr *p, int e) 153 { 154 while (p->num != -1 && p->num != e) 155 p++; 156 return (p); 157 } 158 159 /* 160 * Set error code 161 */ 162 void 163 fetch_seterr(struct fetcherr *p, int e) 164 { 165 p = fetch_finderr(p, e); 166 fetchLastErrCode = p->cat; 167 snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string); 168 } 169 170 /* 171 * Set error code according to errno 172 */ 173 void 174 fetch_syserr(void) 175 { 176 switch (errno) { 177 case 0: 178 fetchLastErrCode = FETCH_OK; 179 break; 180 case EPERM: 181 case EACCES: 182 case EROFS: 183 case EAUTH: 184 case ENEEDAUTH: 185 fetchLastErrCode = FETCH_AUTH; 186 break; 187 case ENOENT: 188 case EISDIR: /* XXX */ 189 fetchLastErrCode = FETCH_UNAVAIL; 190 break; 191 case ENOMEM: 192 fetchLastErrCode = FETCH_MEMORY; 193 break; 194 case EBUSY: 195 case EAGAIN: 196 fetchLastErrCode = FETCH_TEMP; 197 break; 198 case EEXIST: 199 fetchLastErrCode = FETCH_EXISTS; 200 break; 201 case ENOSPC: 202 fetchLastErrCode = FETCH_FULL; 203 break; 204 case EADDRINUSE: 205 case EADDRNOTAVAIL: 206 case ENETDOWN: 207 case ENETUNREACH: 208 case ENETRESET: 209 case EHOSTUNREACH: 210 fetchLastErrCode = FETCH_NETWORK; 211 break; 212 case ECONNABORTED: 213 case ECONNRESET: 214 fetchLastErrCode = FETCH_ABORT; 215 break; 216 case ETIMEDOUT: 217 fetchLastErrCode = FETCH_TIMEOUT; 218 break; 219 case ECONNREFUSED: 220 case EHOSTDOWN: 221 fetchLastErrCode = FETCH_DOWN; 222 break; 223 default: 224 fetchLastErrCode = FETCH_UNKNOWN; 225 } 226 snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno)); 227 } 228 229 230 /* 231 * Emit status message 232 */ 233 void 234 fetch_info(const char *fmt, ...) 235 { 236 va_list ap; 237 int serrno = errno; 238 239 va_start(ap, fmt); 240 vfprintf(stderr, fmt, ap); 241 va_end(ap); 242 fputc('\n', stderr); 243 errno = serrno; 244 } 245 #define fetch_verbose(...) \ 246 do { if (verbose) fetch_info(__VA_ARGS__); } while (0) 247 248 249 /*** Network-related utility functions ***************************************/ 250 251 /* 252 * Return the default port for a scheme 253 */ 254 int 255 fetch_default_port(const char *scheme) 256 { 257 struct servent *se; 258 259 if ((se = getservbyname(scheme, "tcp")) != NULL) 260 return (ntohs(se->s_port)); 261 if (strcmp(scheme, SCHEME_FTP) == 0) 262 return (FTP_DEFAULT_PORT); 263 if (strcmp(scheme, SCHEME_HTTP) == 0) 264 return (HTTP_DEFAULT_PORT); 265 return (0); 266 } 267 268 /* 269 * Return the default proxy port for a scheme 270 */ 271 int 272 fetch_default_proxy_port(const char *scheme) 273 { 274 if (strcmp(scheme, SCHEME_FTP) == 0) 275 return (FTP_DEFAULT_PROXY_PORT); 276 if (strcmp(scheme, SCHEME_HTTP) == 0) 277 return (HTTP_DEFAULT_PROXY_PORT); 278 return (0); 279 } 280 281 282 /* 283 * Create a connection for an existing descriptor. 284 */ 285 conn_t * 286 fetch_reopen(int sd) 287 { 288 conn_t *conn; 289 int flags; 290 #ifdef SO_NOSIGPIPE 291 int opt = 1; 292 #endif 293 294 /* allocate and fill connection structure */ 295 if ((conn = calloc(1, sizeof(*conn))) == NULL) 296 return (NULL); 297 flags = fcntl(sd, F_GETFD); 298 if (flags != -1 && (flags & FD_CLOEXEC) == 0) 299 (void)fcntl(sd, F_SETFD, flags | FD_CLOEXEC); 300 flags = fcntl(sd, F_GETFL); 301 if (flags != -1 && (flags & O_NONBLOCK) == 0) 302 (void)fcntl(sd, F_SETFL, flags | O_NONBLOCK); 303 #ifdef SO_NOSIGPIPE 304 (void)setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof(opt)); 305 #endif 306 conn->sd = sd; 307 ++conn->ref; 308 return (conn); 309 } 310 311 312 /* 313 * Bump a connection's reference count. 314 */ 315 conn_t * 316 fetch_ref(conn_t *conn) 317 { 318 ++conn->ref; 319 return (conn); 320 } 321 322 323 /* 324 * Resolve an address 325 */ 326 struct addrinfo * 327 fetch_resolve(const char *addr, int port, int af) 328 { 329 char hbuf[256], sbuf[8]; 330 struct addrinfo hints, *res; 331 const char *hb, *he, *sep; 332 const char *host, *service; 333 int err, len; 334 335 /* first, check for a bracketed IPv6 address */ 336 if (*addr == '[') { 337 hb = addr + 1; 338 if ((sep = strchr(hb, ']')) == NULL) { 339 errno = EINVAL; 340 goto syserr; 341 } 342 he = sep++; 343 } else { 344 hb = addr; 345 sep = strchrnul(hb, ':'); 346 he = sep; 347 } 348 349 /* see if we need to copy the host name */ 350 if (*he != '\0') { 351 len = snprintf(hbuf, sizeof(hbuf), 352 "%.*s", (int)(he - hb), hb); 353 if (len < 0) 354 goto syserr; 355 if (len >= (int)sizeof(hbuf)) { 356 errno = ENAMETOOLONG; 357 goto syserr; 358 } 359 host = hbuf; 360 } else { 361 host = hb; 362 } 363 364 /* was it followed by a service name? */ 365 if (*sep == '\0' && port != 0) { 366 if (port < 1 || port > 65535) { 367 errno = EINVAL; 368 goto syserr; 369 } 370 if (snprintf(sbuf, sizeof(sbuf), "%d", port) < 0) 371 goto syserr; 372 service = sbuf; 373 } else if (*sep != '\0') { 374 service = sep + 1; 375 } else { 376 service = NULL; 377 } 378 379 /* resolve */ 380 memset(&hints, 0, sizeof(hints)); 381 hints.ai_family = af; 382 hints.ai_socktype = SOCK_STREAM; 383 hints.ai_flags = AI_ADDRCONFIG; 384 if ((err = getaddrinfo(host, service, &hints, &res)) != 0) { 385 netdb_seterr(err); 386 return (NULL); 387 } 388 return (res); 389 syserr: 390 fetch_syserr(); 391 return (NULL); 392 } 393 394 395 /* 396 * Bind a socket to a specific local address 397 */ 398 int 399 fetch_bind(int sd, int af, const char *addr) 400 { 401 struct addrinfo *cliai, *ai; 402 int err; 403 404 if ((cliai = fetch_resolve(addr, 0, af)) == NULL) 405 return (-1); 406 for (ai = cliai; ai != NULL; ai = ai->ai_next) 407 if ((err = bind(sd, ai->ai_addr, ai->ai_addrlen)) == 0) 408 break; 409 if (err != 0) 410 fetch_syserr(); 411 freeaddrinfo(cliai); 412 return (err == 0 ? 0 : -1); 413 } 414 415 416 /* 417 * SOCKS5 connection initiation, based on RFC 1928 418 * Default DNS resolution over SOCKS5 419 */ 420 int 421 fetch_socks5_init(conn_t *conn, const char *host, int port, int verbose) 422 { 423 /* 424 * Size is based on largest packet prefix (4 bytes) + 425 * Largest FQDN (256) + one byte size (1) + 426 * Port (2) 427 */ 428 unsigned char buf[BUFF_SIZE]; 429 unsigned char *ptr; 430 int ret = 1; 431 432 fetch_verbose("Initializing SOCKS5 connection: %s:%d", host, port); 433 434 /* Connection initialization */ 435 ptr = buf; 436 *ptr++ = SOCKS_VERSION_5; 437 *ptr++ = SOCKS_CONNECTION; 438 *ptr++ = SOCKS_RSV; 439 440 if (fetch_write(conn, buf, 3) != 3) { 441 ret = SOCKS5_ERR_SELECTION; 442 goto fail; 443 } 444 445 /* Verify response from SOCKS5 server */ 446 if (fetch_read(conn, buf, 2) != 2) { 447 ret = SOCKS5_ERR_READ_METHOD; 448 goto fail; 449 } 450 451 ptr = buf; 452 if (ptr[0] != SOCKS_VERSION_5) { 453 ret = SOCKS5_ERR_VER5_ONLY; 454 goto fail; 455 } 456 if (ptr[1] == SOCKS_NOMETHODS) { 457 ret = SOCKS5_ERR_NOMETHODS; 458 goto fail; 459 } 460 else if (ptr[1] != SOCKS5_NOTIMPLEMENTED) { 461 ret = SOCKS5_ERR_NOTIMPLEMENTED; 462 goto fail; 463 } 464 465 /* Send Request */ 466 *ptr++ = SOCKS_VERSION_5; 467 *ptr++ = SOCKS_CONNECTION; 468 *ptr++ = SOCKS_RSV; 469 /* Encode all targets as a hostname to avoid DNS leaks */ 470 *ptr++ = SOCKS_ATYP_DOMAINNAME; 471 if (strlen(host) > FQDN_SIZE) { 472 ret = SOCKS5_ERR_HOSTNAME_SIZE; 473 goto fail; 474 } 475 *ptr++ = strlen(host); 476 memcpy(ptr, host, strlen(host)); 477 ptr = ptr + strlen(host); 478 479 port = htons(port); 480 *ptr++ = port & 0x00ff; 481 *ptr++ = (port & 0xff00) >> 8; 482 483 if (fetch_write(conn, buf, ptr - buf) != ptr - buf) { 484 ret = SOCKS5_ERR_REQUEST; 485 goto fail; 486 } 487 488 /* BND.ADDR is variable length, read the largest on non-blocking socket */ 489 if (!fetch_read(conn, buf, BUFF_SIZE)) { 490 ret = SOCKS5_ERR_REPLY; 491 goto fail; 492 } 493 494 ptr = buf; 495 if (*ptr++ != SOCKS_VERSION_5) { 496 ret = SOCKS5_ERR_NON_VER5_RESP; 497 goto fail; 498 } 499 500 switch (*ptr++) { 501 case SOCKS_SUCCESS: 502 break; 503 case SOCKS_GENERAL_FAILURE: 504 ret = SOCKS5_ERR_GENERAL; 505 goto fail; 506 case SOCKS_CONNECTION_NOT_ALLOWED: 507 ret = SOCKS5_ERR_NOT_ALLOWED; 508 goto fail; 509 case SOCKS_NETWORK_UNREACHABLE: 510 ret = SOCKS5_ERR_NET_UNREACHABLE; 511 goto fail; 512 case SOCKS_HOST_UNREACHABLE: 513 ret = SOCKS5_ERR_HOST_UNREACHABLE; 514 goto fail; 515 case SOCKS_CONNECTION_REFUSED: 516 ret = SOCKS5_ERR_CONN_REFUSED; 517 goto fail; 518 case SOCKS_TTL_EXPIRED: 519 ret = SOCKS5_ERR_TTL_EXPIRED; 520 goto fail; 521 case SOCKS_COMMAND_NOT_SUPPORTED: 522 ret = SOCKS5_ERR_COM_UNSUPPORTED; 523 goto fail; 524 case SOCKS_ADDRESS_NOT_SUPPORTED: 525 ret = SOCKS5_ERR_ADDR_UNSUPPORTED; 526 goto fail; 527 default: 528 ret = SOCKS5_ERR_UNSPECIFIED; 529 goto fail; 530 } 531 532 return (ret); 533 534 fail: 535 socks5_seterr(ret); 536 return (0); 537 } 538 539 /* 540 * Perform SOCKS5 initialization 541 */ 542 int 543 fetch_socks5_getenv(char **host, int *port) 544 { 545 char *socks5env, *endptr, *ext; 546 const char *portDelim; 547 size_t slen; 548 549 portDelim = ":"; 550 if ((socks5env = getenv("SOCKS5_PROXY")) == NULL || *socks5env == '\0') { 551 *host = NULL; 552 *port = -1; 553 return (-1); 554 } 555 556 /* 557 * IPv6 addresses begin and end in brackets. Set the port delimiter 558 * accordingly and search for it so we can do appropriate validation. 559 */ 560 if (socks5env[0] == '[') 561 portDelim = "]:"; 562 563 slen = strlen(socks5env); 564 ext = strstr(socks5env, portDelim); 565 if (socks5env[0] == '[') { 566 if (socks5env[slen - 1] == ']') { 567 *host = strndup(socks5env, slen); 568 } else if (ext != NULL) { 569 *host = strndup(socks5env, ext - socks5env + 1); 570 } else { 571 socks5_seterr(SOCKS5_ERR_BAD_PROXY_FORMAT); 572 return (0); 573 } 574 } else { 575 *host = strndup(socks5env, ext - socks5env); 576 } 577 578 if (*host == NULL) 579 return (-1); 580 if (ext == NULL) { 581 *port = 1080; /* Default port as defined in RFC1928 */ 582 } else { 583 ext += strlen(portDelim); 584 errno = 0; 585 *port = strtoimax(ext, (char **)&endptr, 10); 586 if (*endptr != '\0' || errno != 0 || *port < 0 || 587 *port > 65535) { 588 free(*host); 589 *host = NULL; 590 socks5_seterr(SOCKS5_ERR_BAD_PORT); 591 return (0); 592 } 593 } 594 595 return (2); 596 } 597 598 599 /* 600 * Establish a TCP connection to the specified port on the specified host. 601 */ 602 conn_t * 603 fetch_connect(const char *host, int port, int af, int verbose) 604 { 605 struct addrinfo *cais = NULL, *sais = NULL, *cai, *sai; 606 const char *bindaddr; 607 conn_t *conn = NULL; 608 int err = 0, sd = -1; 609 char *sockshost; 610 int socksport; 611 612 DEBUGF("---> %s:%d\n", host, port); 613 614 /* 615 * Check if SOCKS5_PROXY env variable is set. fetch_socks5_getenv 616 * will either set sockshost = NULL or allocate memory in all cases. 617 */ 618 sockshost = NULL; 619 if (!fetch_socks5_getenv(&sockshost, &socksport)) 620 goto fail; 621 622 /* Not using SOCKS5 proxy */ 623 if (sockshost == NULL) { 624 /* resolve server address */ 625 fetch_verbose("resolving server address: %s:%d", host, port); 626 if ((sais = fetch_resolve(host, port, af)) == NULL) 627 goto fail; 628 629 /* resolve client address */ 630 bindaddr = getenv("FETCH_BIND_ADDRESS"); 631 if (bindaddr != NULL && *bindaddr != '\0') { 632 fetch_verbose("resolving client address: %s", bindaddr); 633 if ((cais = fetch_resolve(bindaddr, 0, af)) == NULL) 634 goto fail; 635 } 636 } else { 637 /* resolve socks5 proxy address */ 638 fetch_verbose("resolving SOCKS5 server address: %s:%d", 639 sockshost, socksport); 640 if ((sais = fetch_resolve(sockshost, socksport, af)) == NULL) { 641 socks5_seterr(SOCKS5_ERR_BAD_HOST); 642 goto fail; 643 } 644 } 645 646 /* try each server address in turn */ 647 for (err = 0, sai = sais; sai != NULL; sai = sai->ai_next) { 648 /* open socket */ 649 if ((sd = socket(sai->ai_family, SOCK_STREAM, 0)) < 0) { 650 err = -1; 651 if (errno == EAFNOSUPPORT || errno == EPROTONOSUPPORT) 652 continue; 653 goto syserr; 654 } 655 /* attempt to bind to client address */ 656 for (err = 0, cai = cais; cai != NULL; cai = cai->ai_next) { 657 if (cai->ai_family != sai->ai_family) 658 continue; 659 if ((err = bind(sd, cai->ai_addr, cai->ai_addrlen)) == 0) 660 break; 661 } 662 if (err != 0) { 663 fetch_verbose("failed to bind to %s", bindaddr); 664 goto syserr; 665 } 666 /* attempt to connect to server address */ 667 while ((err = connect(sd, sai->ai_addr, sai->ai_addrlen)) < 0) { 668 if (errno == EINTR && fetchRestartCalls) 669 continue; 670 break; 671 } 672 /* success? */ 673 if (err == 0) 674 break; 675 /* clean up before next attempt */ 676 close(sd); 677 sd = -1; 678 } 679 if (err != 0) { 680 if (verbose && sockshost == NULL) { 681 fetch_info("failed to connect to %s:%d", host, port); 682 goto syserr; 683 } else if (sockshost != NULL) { 684 fetch_verbose("failed to connect to SOCKS5 server %s:%d", 685 sockshost, socksport); 686 socks5_seterr(SOCKS5_ERR_CONN_REFUSED); 687 goto fail; 688 } 689 goto syserr; 690 } 691 692 if ((conn = fetch_reopen(sd)) == NULL) 693 goto syserr; 694 695 if (sockshost) 696 if (!fetch_socks5_init(conn, host, port, verbose)) 697 goto fail; 698 free(sockshost); 699 if (cais != NULL) 700 freeaddrinfo(cais); 701 if (sais != NULL) 702 freeaddrinfo(sais); 703 return (conn); 704 syserr: 705 fetch_syserr(); 706 fail: 707 free(sockshost); 708 /* Fully close if it was opened; otherwise just don't leak the fd. */ 709 if (conn != NULL) 710 fetch_close(conn); 711 else if (sd >= 0) 712 close(sd); 713 if (cais != NULL) 714 freeaddrinfo(cais); 715 if (sais != NULL) 716 freeaddrinfo(sais); 717 return (NULL); 718 } 719 720 #ifdef WITH_SSL 721 /* 722 * Convert characters A-Z to lowercase (intentionally avoid any locale 723 * specific conversions). 724 */ 725 static char 726 fetch_ssl_tolower(char in) 727 { 728 if (in >= 'A' && in <= 'Z') 729 return (in + 32); 730 else 731 return (in); 732 } 733 734 /* 735 * isalpha implementation that intentionally avoids any locale specific 736 * conversions. 737 */ 738 static int 739 fetch_ssl_isalpha(char in) 740 { 741 return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z')); 742 } 743 744 /* 745 * Check if passed hostnames a and b are equal. 746 */ 747 static int 748 fetch_ssl_hname_equal(const char *a, size_t alen, const char *b, 749 size_t blen) 750 { 751 size_t i; 752 753 if (alen != blen) 754 return (0); 755 for (i = 0; i < alen; ++i) { 756 if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i])) 757 return (0); 758 } 759 return (1); 760 } 761 762 /* 763 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9 764 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha- 765 * numeric characters. Double hyphens (like they're found in IDN a-labels 766 * 'xn--') are not allowed. Empty labels are invalid. 767 */ 768 static int 769 fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok) 770 { 771 size_t i; 772 773 if (!len || l[0] == '-' || l[len-1] == '-') 774 return (0); 775 for (i = 0; i < len; ++i) { 776 if (!isdigit(l[i]) && 777 !fetch_ssl_isalpha(l[i]) && 778 !(l[i] == '*' && wcok) && 779 !(l[i] == '-' && l[i - 1] != '-')) 780 return (0); 781 } 782 return (1); 783 } 784 785 /* 786 * Check if host name consists only of numbers. This might indicate an IP 787 * address, which is not a good idea for CN wildcard comparison. 788 */ 789 static int 790 fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len) 791 { 792 size_t i; 793 794 for (i = 0; i < len; ++i) { 795 if (!((hostname[i] >= '0' && hostname[i] <= '9') || 796 hostname[i] == '.')) 797 return (0); 798 } 799 return (1); 800 } 801 802 /* 803 * Check if the host name h passed matches the pattern passed in m which 804 * is usually part of subjectAltName or CN of a certificate presented to 805 * the client. This includes wildcard matching. The algorithm is based on 806 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280. 807 */ 808 static int 809 fetch_ssl_hname_match(const char *h, size_t hlen, const char *m, 810 size_t mlen) 811 { 812 int delta, hdotidx, mdot1idx, wcidx; 813 const char *hdot, *mdot1, *mdot2; 814 const char *wc; /* wildcard */ 815 816 if (!(h && *h && m && *m)) 817 return (0); 818 if ((wc = strnstr(m, "*", mlen)) == NULL) 819 return (fetch_ssl_hname_equal(h, hlen, m, mlen)); 820 wcidx = wc - m; 821 /* hostname should not be just dots and numbers */ 822 if (fetch_ssl_hname_is_only_numbers(h, hlen)) 823 return (0); 824 /* only one wildcard allowed in pattern */ 825 if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL) 826 return (0); 827 /* 828 * there must be at least two more domain labels and 829 * wildcard has to be in the leftmost label (RFC6125) 830 */ 831 mdot1 = strnstr(m, ".", mlen); 832 if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4) 833 return (0); 834 mdot1idx = mdot1 - m; 835 mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1); 836 if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2) 837 return (0); 838 /* hostname must contain a dot and not be the 1st char */ 839 hdot = strnstr(h, ".", hlen); 840 if (hdot == NULL || hdot == h) 841 return (0); 842 hdotidx = hdot - h; 843 /* 844 * host part of hostname must be at least as long as 845 * pattern it's supposed to match 846 */ 847 if (hdotidx < mdot1idx) 848 return (0); 849 /* 850 * don't allow wildcards in non-traditional domain names 851 * (IDN, A-label, U-label...) 852 */ 853 if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) || 854 !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1)) 855 return (0); 856 /* match domain part (part after first dot) */ 857 if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1, 858 mlen - mdot1idx)) 859 return (0); 860 /* match part left of wildcard */ 861 if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx)) 862 return (0); 863 /* match part right of wildcard */ 864 delta = mdot1idx - wcidx - 1; 865 if (!fetch_ssl_hname_equal(hdot - delta, delta, 866 mdot1 - delta, delta)) 867 return (0); 868 /* all tests succeeded, it's a match */ 869 return (1); 870 } 871 872 /* 873 * Get numeric host address info - returns NULL if host was not an IP 874 * address. The caller is responsible for deallocation using 875 * freeaddrinfo(3). 876 */ 877 static struct addrinfo * 878 fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len) 879 { 880 struct addrinfo hints, *res; 881 char *host; 882 883 host = (char *)malloc(len + 1); 884 memcpy(host, hostname, len); 885 host[len] = '\0'; 886 memset(&hints, 0, sizeof(hints)); 887 hints.ai_family = PF_UNSPEC; 888 hints.ai_socktype = SOCK_STREAM; 889 hints.ai_protocol = 0; 890 hints.ai_flags = AI_NUMERICHOST; 891 /* port is not relevant for this purpose */ 892 if (getaddrinfo(host, "443", &hints, &res) != 0) 893 res = NULL; 894 free(host); 895 return res; 896 } 897 898 /* 899 * Compare ip address in addrinfo with address passes. 900 */ 901 static int 902 fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost, 903 size_t rhostlen) 904 { 905 const void *left; 906 907 if (lhost->ai_family == AF_INET && rhostlen == 4) { 908 left = (void *)&((struct sockaddr_in*)(void *) 909 lhost->ai_addr)->sin_addr.s_addr; 910 #ifdef INET6 911 } else if (lhost->ai_family == AF_INET6 && rhostlen == 16) { 912 left = (void *)&((struct sockaddr_in6 *)(void *) 913 lhost->ai_addr)->sin6_addr; 914 #endif 915 } else 916 return (0); 917 return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0); 918 } 919 920 /* 921 * Compare ip address in addrinfo with host passed. If host is not an IP 922 * address, comparison will fail. 923 */ 924 static int 925 fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r, 926 size_t rlen) 927 { 928 struct addrinfo *raddr; 929 int ret; 930 char *rip; 931 932 ret = 0; 933 if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL) 934 return 0; /* not a numeric host */ 935 936 if (laddr->ai_family == raddr->ai_family) { 937 if (laddr->ai_family == AF_INET) { 938 rip = (char *)&((struct sockaddr_in *)(void *) 939 raddr->ai_addr)->sin_addr.s_addr; 940 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4); 941 #ifdef INET6 942 } else if (laddr->ai_family == AF_INET6) { 943 rip = (char *)&((struct sockaddr_in6 *)(void *) 944 raddr->ai_addr)->sin6_addr; 945 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16); 946 #endif 947 } 948 949 } 950 freeaddrinfo(raddr); 951 return (ret); 952 } 953 954 /* 955 * Verify server certificate by subjectAltName. 956 */ 957 static int 958 fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames, 959 const char *host, struct addrinfo *ip) 960 { 961 const GENERAL_NAME *name; 962 size_t nslen; 963 int i; 964 const char *ns; 965 966 for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) { 967 name = sk_GENERAL_NAME_value(altnames, i); 968 ns = (const char *)ASN1_STRING_get0_data(name->d.ia5); 969 nslen = (size_t)ASN1_STRING_length(name->d.ia5); 970 971 if (name->type == GEN_DNS && ip == NULL && 972 fetch_ssl_hname_match(host, strlen(host), ns, nslen)) 973 return (1); 974 else if (name->type == GEN_IPADD && ip != NULL && 975 fetch_ssl_ipaddr_match_bin(ip, ns, nslen)) 976 return (1); 977 } 978 return (0); 979 } 980 981 /* 982 * Verify server certificate by CN. 983 */ 984 static int 985 fetch_ssl_verify_cn(X509_NAME *subject, const char *host, 986 struct addrinfo *ip) 987 { 988 ASN1_STRING *namedata; 989 X509_NAME_ENTRY *nameentry; 990 int cnlen, lastpos, loc, ret; 991 unsigned char *cn; 992 993 ret = 0; 994 lastpos = -1; 995 loc = -1; 996 cn = NULL; 997 /* get most specific CN (last entry in list) and compare */ 998 while ((lastpos = X509_NAME_get_index_by_NID(subject, 999 NID_commonName, lastpos)) != -1) 1000 loc = lastpos; 1001 1002 if (loc > -1) { 1003 nameentry = X509_NAME_get_entry(subject, loc); 1004 namedata = X509_NAME_ENTRY_get_data(nameentry); 1005 cnlen = ASN1_STRING_to_UTF8(&cn, namedata); 1006 if (ip == NULL && 1007 fetch_ssl_hname_match(host, strlen(host), cn, cnlen)) 1008 ret = 1; 1009 else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen)) 1010 ret = 1; 1011 OPENSSL_free(cn); 1012 } 1013 return (ret); 1014 } 1015 1016 /* 1017 * Verify that server certificate subjectAltName/CN matches 1018 * hostname. First check, if there are alternative subject names. If yes, 1019 * those have to match. Only if those don't exist it falls back to 1020 * checking the subject's CN. 1021 */ 1022 static int 1023 fetch_ssl_verify_hname(X509 *cert, const char *host) 1024 { 1025 struct addrinfo *ip; 1026 STACK_OF(GENERAL_NAME) *altnames; 1027 X509_NAME *subject; 1028 int ret; 1029 1030 ret = 0; 1031 ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host)); 1032 altnames = X509_get_ext_d2i(cert, NID_subject_alt_name, 1033 NULL, NULL); 1034 1035 if (altnames != NULL) { 1036 ret = fetch_ssl_verify_altname(altnames, host, ip); 1037 } else { 1038 subject = X509_get_subject_name(cert); 1039 if (subject != NULL) 1040 ret = fetch_ssl_verify_cn(subject, host, ip); 1041 } 1042 1043 if (ip != NULL) 1044 freeaddrinfo(ip); 1045 if (altnames != NULL) 1046 GENERAL_NAMES_free(altnames); 1047 return (ret); 1048 } 1049 1050 /* 1051 * Configure transport security layer based on environment. 1052 */ 1053 static void 1054 fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose) 1055 { 1056 long ssl_ctx_options; 1057 1058 ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_SSLv3 | SSL_OP_NO_TICKET; 1059 if (getenv("SSL_NO_TLS1") != NULL) 1060 ssl_ctx_options |= SSL_OP_NO_TLSv1; 1061 if (getenv("SSL_NO_TLS1_1") != NULL) 1062 ssl_ctx_options |= SSL_OP_NO_TLSv1_1; 1063 if (getenv("SSL_NO_TLS1_2") != NULL) 1064 ssl_ctx_options |= SSL_OP_NO_TLSv1_2; 1065 if (getenv("SSL_NO_TLS1_3") != NULL) 1066 ssl_ctx_options |= SSL_OP_NO_TLSv1_3; 1067 fetch_verbose("SSL options: %lx", ssl_ctx_options); 1068 SSL_CTX_set_options(ctx, ssl_ctx_options); 1069 } 1070 1071 1072 /* 1073 * Configure peer verification based on environment. 1074 */ 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 ca_cert_path = getenv("SSL_CA_CERT_PATH"); 1085 if (verbose) { 1086 fetch_info("Peer verification enabled"); 1087 if (ca_cert_file != NULL) 1088 fetch_info("Using CA cert file: %s", 1089 ca_cert_file); 1090 if (ca_cert_path != NULL) 1091 fetch_info("Using CA cert path: %s", 1092 ca_cert_path); 1093 if (ca_cert_file == NULL && ca_cert_path == NULL) 1094 fetch_info("Using OpenSSL default " 1095 "CA cert file and path"); 1096 } 1097 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, 1098 fetch_ssl_cb_verify_crt); 1099 if (ca_cert_file != NULL || ca_cert_path != NULL) 1100 SSL_CTX_load_verify_locations(ctx, ca_cert_file, 1101 ca_cert_path); 1102 else 1103 SSL_CTX_set_default_verify_paths(ctx); 1104 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) { 1105 fetch_verbose("Using CRL file: %s", crl_file); 1106 crl_store = SSL_CTX_get_cert_store(ctx); 1107 crl_lookup = X509_STORE_add_lookup(crl_store, 1108 X509_LOOKUP_file()); 1109 if (crl_lookup == NULL || 1110 !X509_load_crl_file(crl_lookup, crl_file, 1111 X509_FILETYPE_PEM)) { 1112 fetch_info("Could not load CRL file %s", 1113 crl_file); 1114 return (0); 1115 } 1116 X509_STORE_set_flags(crl_store, 1117 X509_V_FLAG_CRL_CHECK | 1118 X509_V_FLAG_CRL_CHECK_ALL); 1119 } 1120 } 1121 return (1); 1122 } 1123 1124 /* 1125 * Configure client certificate based on environment. 1126 */ 1127 static int 1128 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose) 1129 { 1130 const char *client_cert_file, *client_key_file; 1131 1132 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) { 1133 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ? 1134 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file; 1135 fetch_verbose("Using client cert file: %s", client_cert_file); 1136 fetch_verbose("Using client key file: %s", client_key_file); 1137 if (SSL_CTX_use_certificate_chain_file(ctx, 1138 client_cert_file) != 1) { 1139 fetch_info("Could not load client certificate %s", 1140 client_cert_file); 1141 return (0); 1142 } 1143 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file, 1144 SSL_FILETYPE_PEM) != 1) { 1145 fetch_info("Could not load client key %s", 1146 client_key_file); 1147 return (0); 1148 } 1149 } 1150 return (1); 1151 } 1152 1153 /* 1154 * Callback for SSL certificate verification, this is called on server 1155 * cert verification. It takes no decision, but informs the user in case 1156 * verification failed. 1157 */ 1158 int 1159 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx) 1160 { 1161 X509 *crt; 1162 X509_NAME *name; 1163 char *str; 1164 1165 str = NULL; 1166 if (!verified) { 1167 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL && 1168 (name = X509_get_subject_name(crt)) != NULL) 1169 str = X509_NAME_oneline(name, 0, 0); 1170 fetch_info("Certificate verification failed for %s", 1171 str != NULL ? str : "no relevant certificate"); 1172 OPENSSL_free(str); 1173 } 1174 return (verified); 1175 } 1176 1177 #endif 1178 1179 /* 1180 * Enable SSL on a connection. 1181 */ 1182 int 1183 fetch_ssl(conn_t *conn, const struct url *URL, int verbose) 1184 { 1185 #ifdef WITH_SSL 1186 int ret, ssl_err; 1187 X509_NAME *name; 1188 char *str; 1189 1190 if ((conn->ssl_ctx = SSL_CTX_new(TLS_client_method())) == NULL) { 1191 fetch_info("SSL context creation failed"); 1192 ERR_print_errors_fp(stderr); 1193 return (-1); 1194 } 1195 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY); 1196 1197 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose); 1198 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose)) 1199 return (-1); 1200 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose)) 1201 return (-1); 1202 1203 conn->ssl = SSL_new(conn->ssl_ctx); 1204 if (conn->ssl == NULL) { 1205 fetch_info("SSL connection creation failed"); 1206 ERR_print_errors_fp(stderr); 1207 return (-1); 1208 } 1209 SSL_set_fd(conn->ssl, conn->sd); 1210 1211 #if !defined(OPENSSL_NO_TLSEXT) 1212 if (!SSL_set_tlsext_host_name(conn->ssl, __DECONST(char *, URL->host))) { 1213 fetch_info("Failed to set TLS server name indication for host %s", 1214 URL->host); 1215 return (-1); 1216 } 1217 #endif 1218 while ((ret = SSL_connect(conn->ssl)) == -1) { 1219 ssl_err = SSL_get_error(conn->ssl, ret); 1220 if (ssl_err != SSL_ERROR_WANT_READ && 1221 ssl_err != SSL_ERROR_WANT_WRITE) { 1222 ERR_print_errors_fp(stderr); 1223 return (-1); 1224 } 1225 } 1226 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl); 1227 1228 if (conn->ssl_cert == NULL) { 1229 fetch_info("No server SSL certificate"); 1230 return (-1); 1231 } 1232 1233 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) { 1234 fetch_verbose("Verify hostname"); 1235 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) { 1236 fetch_info("SSL certificate subject does not match host %s", 1237 URL->host); 1238 return (-1); 1239 } 1240 } 1241 1242 if (verbose) { 1243 fetch_info("%s connection established using %s", 1244 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl)); 1245 name = X509_get_subject_name(conn->ssl_cert); 1246 str = X509_NAME_oneline(name, 0, 0); 1247 fetch_info("Certificate subject: %s", str); 1248 OPENSSL_free(str); 1249 name = X509_get_issuer_name(conn->ssl_cert); 1250 str = X509_NAME_oneline(name, 0, 0); 1251 fetch_info("Certificate issuer: %s", str); 1252 OPENSSL_free(str); 1253 } 1254 1255 return (0); 1256 #else 1257 (void)conn; 1258 (void)verbose; 1259 (void)URL; 1260 fetch_info("SSL support disabled"); 1261 return (-1); 1262 #endif 1263 } 1264 1265 #define FETCH_READ_WAIT -2 1266 #define FETCH_READ_ERROR -1 1267 #define FETCH_READ_DONE 0 1268 1269 #ifdef WITH_SSL 1270 static ssize_t 1271 fetch_ssl_read(SSL *ssl, char *buf, size_t len) 1272 { 1273 ssize_t rlen; 1274 int ssl_err; 1275 1276 rlen = SSL_read(ssl, buf, len); 1277 if (rlen < 0) { 1278 ssl_err = SSL_get_error(ssl, rlen); 1279 if (ssl_err == SSL_ERROR_WANT_READ || 1280 ssl_err == SSL_ERROR_WANT_WRITE) { 1281 return (FETCH_READ_WAIT); 1282 } else { 1283 ERR_print_errors_fp(stderr); 1284 return (FETCH_READ_ERROR); 1285 } 1286 } 1287 return (rlen); 1288 } 1289 #endif 1290 1291 static ssize_t 1292 fetch_socket_read(int sd, char *buf, size_t len) 1293 { 1294 ssize_t rlen; 1295 1296 rlen = read(sd, buf, len); 1297 if (rlen < 0) { 1298 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls)) { 1299 return (FETCH_READ_WAIT); 1300 } else { 1301 return (FETCH_READ_ERROR); 1302 } 1303 } 1304 return (rlen); 1305 } 1306 1307 /* 1308 * Read a character from a connection w/ timeout 1309 */ 1310 ssize_t 1311 fetch_read(conn_t *conn, char *buf, size_t len) 1312 { 1313 struct timeval now, timeout, delta; 1314 struct pollfd pfd; 1315 ssize_t rlen; 1316 int deltams; 1317 1318 if (fetchTimeout > 0) { 1319 gettimeofday(&timeout, NULL); 1320 timeout.tv_sec += fetchTimeout; 1321 } 1322 1323 deltams = INFTIM; 1324 memset(&pfd, 0, sizeof pfd); 1325 pfd.fd = conn->sd; 1326 pfd.events = POLLIN | POLLERR; 1327 1328 for (;;) { 1329 /* 1330 * The socket is non-blocking. Instead of the canonical 1331 * poll() -> read(), we do the following: 1332 * 1333 * 1) call read() or SSL_read(). 1334 * 2) if we received some data, return it. 1335 * 3) if an error occurred, return -1. 1336 * 4) if read() or SSL_read() signaled EOF, return. 1337 * 5) if we did not receive any data but we're not at EOF, 1338 * call poll(). 1339 * 1340 * In the SSL case, this is necessary because if we 1341 * receive a close notification, we have to call 1342 * SSL_read() one additional time after we've read 1343 * everything we received. 1344 * 1345 * In the non-SSL case, it may improve performance (very 1346 * slightly) when reading small amounts of data. 1347 */ 1348 #ifdef WITH_SSL 1349 if (conn->ssl != NULL) 1350 rlen = fetch_ssl_read(conn->ssl, buf, len); 1351 else 1352 #endif 1353 rlen = fetch_socket_read(conn->sd, buf, len); 1354 if (rlen >= 0) { 1355 break; 1356 } else if (rlen == FETCH_READ_ERROR) { 1357 fetch_syserr(); 1358 return (-1); 1359 } 1360 // assert(rlen == FETCH_READ_WAIT); 1361 if (fetchTimeout > 0) { 1362 gettimeofday(&now, NULL); 1363 if (!timercmp(&timeout, &now, >)) { 1364 errno = ETIMEDOUT; 1365 fetch_syserr(); 1366 return (-1); 1367 } 1368 timersub(&timeout, &now, &delta); 1369 deltams = delta.tv_sec * 1000 + 1370 delta.tv_usec / 1000; 1371 } 1372 errno = 0; 1373 pfd.revents = 0; 1374 if (poll(&pfd, 1, deltams) < 0) { 1375 if (errno == EINTR && fetchRestartCalls) 1376 continue; 1377 fetch_syserr(); 1378 return (-1); 1379 } 1380 } 1381 return (rlen); 1382 } 1383 1384 1385 /* 1386 * Read a line of text from a connection w/ timeout 1387 */ 1388 #define MIN_BUF_SIZE 1024 1389 1390 int 1391 fetch_getln(conn_t *conn) 1392 { 1393 char *tmp; 1394 size_t tmpsize; 1395 ssize_t len; 1396 char c; 1397 1398 if (conn->buf == NULL) { 1399 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) { 1400 errno = ENOMEM; 1401 return (-1); 1402 } 1403 conn->bufsize = MIN_BUF_SIZE; 1404 } 1405 1406 conn->buf[0] = '\0'; 1407 conn->buflen = 0; 1408 1409 do { 1410 len = fetch_read(conn, &c, 1); 1411 if (len == -1) 1412 return (-1); 1413 if (len == 0) 1414 break; 1415 conn->buf[conn->buflen++] = c; 1416 if (conn->buflen == conn->bufsize) { 1417 tmp = conn->buf; 1418 tmpsize = conn->bufsize * 2 + 1; 1419 if ((tmp = realloc(tmp, tmpsize)) == NULL) { 1420 errno = ENOMEM; 1421 return (-1); 1422 } 1423 conn->buf = tmp; 1424 conn->bufsize = tmpsize; 1425 } 1426 } while (c != '\n'); 1427 1428 conn->buf[conn->buflen] = '\0'; 1429 DEBUGF("<<< %s", conn->buf); 1430 return (0); 1431 } 1432 1433 1434 /* 1435 * Write to a connection w/ timeout 1436 */ 1437 ssize_t 1438 fetch_write(conn_t *conn, const char *buf, size_t len) 1439 { 1440 struct iovec iov; 1441 1442 iov.iov_base = __DECONST(char *, buf); 1443 iov.iov_len = len; 1444 return (fetch_writev(conn, &iov, 1)); 1445 } 1446 1447 /* 1448 * Write a vector to a connection w/ timeout 1449 * Note: can modify the iovec. 1450 */ 1451 ssize_t 1452 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt) 1453 { 1454 struct timeval now, timeout, delta; 1455 struct pollfd pfd; 1456 ssize_t wlen, total; 1457 int deltams; 1458 1459 memset(&pfd, 0, sizeof pfd); 1460 if (fetchTimeout) { 1461 pfd.fd = conn->sd; 1462 pfd.events = POLLOUT | POLLERR; 1463 gettimeofday(&timeout, NULL); 1464 timeout.tv_sec += fetchTimeout; 1465 } 1466 1467 total = 0; 1468 while (iovcnt > 0) { 1469 while (fetchTimeout && pfd.revents == 0) { 1470 gettimeofday(&now, NULL); 1471 if (!timercmp(&timeout, &now, >)) { 1472 errno = ETIMEDOUT; 1473 fetch_syserr(); 1474 return (-1); 1475 } 1476 timersub(&timeout, &now, &delta); 1477 deltams = delta.tv_sec * 1000 + 1478 delta.tv_usec / 1000; 1479 errno = 0; 1480 pfd.revents = 0; 1481 if (poll(&pfd, 1, deltams) < 0) { 1482 /* POSIX compliance */ 1483 if (errno == EAGAIN) 1484 continue; 1485 if (errno == EINTR && fetchRestartCalls) 1486 continue; 1487 return (-1); 1488 } 1489 } 1490 errno = 0; 1491 #ifdef WITH_SSL 1492 if (conn->ssl != NULL) 1493 wlen = SSL_write(conn->ssl, 1494 iov->iov_base, iov->iov_len); 1495 else 1496 #endif 1497 wlen = writev(conn->sd, iov, iovcnt); 1498 if (wlen == 0) { 1499 /* we consider a short write a failure */ 1500 /* XXX perhaps we shouldn't in the SSL case */ 1501 errno = EPIPE; 1502 fetch_syserr(); 1503 return (-1); 1504 } 1505 if (wlen < 0) { 1506 if (errno == EINTR && fetchRestartCalls) 1507 continue; 1508 return (-1); 1509 } 1510 total += wlen; 1511 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) { 1512 wlen -= iov->iov_len; 1513 iov++; 1514 iovcnt--; 1515 } 1516 if (iovcnt > 0) { 1517 iov->iov_len -= wlen; 1518 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen; 1519 } 1520 } 1521 return (total); 1522 } 1523 1524 1525 /* 1526 * Write a line of text to a connection w/ timeout 1527 */ 1528 int 1529 fetch_putln(conn_t *conn, const char *str, size_t len) 1530 { 1531 struct iovec iov[2]; 1532 int ret; 1533 1534 DEBUGF(">>> %s\n", str); 1535 iov[0].iov_base = __DECONST(char *, str); 1536 iov[0].iov_len = len; 1537 iov[1].iov_base = __DECONST(char *, ENDL); 1538 iov[1].iov_len = sizeof(ENDL); 1539 if (len == 0) 1540 ret = fetch_writev(conn, &iov[1], 1); 1541 else 1542 ret = fetch_writev(conn, iov, 2); 1543 if (ret == -1) 1544 return (-1); 1545 return (0); 1546 } 1547 1548 1549 /* 1550 * Close connection 1551 */ 1552 int 1553 fetch_close(conn_t *conn) 1554 { 1555 int ret; 1556 1557 if (--conn->ref > 0) 1558 return (0); 1559 #ifdef WITH_SSL 1560 if (conn->ssl) { 1561 SSL_shutdown(conn->ssl); 1562 SSL_set_connect_state(conn->ssl); 1563 SSL_free(conn->ssl); 1564 conn->ssl = NULL; 1565 } 1566 if (conn->ssl_ctx) { 1567 SSL_CTX_free(conn->ssl_ctx); 1568 conn->ssl_ctx = NULL; 1569 } 1570 if (conn->ssl_cert) { 1571 X509_free(conn->ssl_cert); 1572 conn->ssl_cert = NULL; 1573 } 1574 #endif 1575 ret = close(conn->sd); 1576 free(conn->buf); 1577 free(conn); 1578 return (ret); 1579 } 1580 1581 1582 /*** Directory-related utility functions *************************************/ 1583 1584 int 1585 fetch_add_entry(struct url_ent **p, int *size, int *len, 1586 const char *name, struct url_stat *us) 1587 { 1588 struct url_ent *tmp; 1589 1590 if (*p == NULL) { 1591 *size = 0; 1592 *len = 0; 1593 } 1594 1595 if (*len >= *size - 1) { 1596 tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p)); 1597 if (tmp == NULL) { 1598 errno = ENOMEM; 1599 fetch_syserr(); 1600 return (-1); 1601 } 1602 *size = (*size * 2 + 1); 1603 *p = tmp; 1604 } 1605 1606 tmp = *p + *len; 1607 snprintf(tmp->name, PATH_MAX, "%s", name); 1608 memcpy(&tmp->stat, us, sizeof(*us)); 1609 1610 (*len)++; 1611 (++tmp)->name[0] = 0; 1612 1613 return (0); 1614 } 1615 1616 1617 /*** Authentication-related utility functions ********************************/ 1618 1619 static const char * 1620 fetch_read_word(FILE *f) 1621 { 1622 static char word[1024]; 1623 1624 if (fscanf(f, " %1023s ", word) != 1) 1625 return (NULL); 1626 return (word); 1627 } 1628 1629 static int 1630 fetch_netrc_open(void) 1631 { 1632 struct passwd *pwd; 1633 char fn[PATH_MAX]; 1634 const char *p; 1635 int fd, serrno; 1636 1637 if ((p = getenv("NETRC")) != NULL) { 1638 DEBUGF("NETRC=%s\n", p); 1639 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) { 1640 fetch_info("$NETRC specifies a file name " 1641 "longer than PATH_MAX"); 1642 return (-1); 1643 } 1644 } else { 1645 if ((p = getenv("HOME")) == NULL) { 1646 if ((pwd = getpwuid(getuid())) == NULL || 1647 (p = pwd->pw_dir) == NULL) 1648 return (-1); 1649 } 1650 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn)) 1651 return (-1); 1652 } 1653 1654 if ((fd = open(fn, O_RDONLY)) < 0) { 1655 serrno = errno; 1656 DEBUGF("%s: %s\n", fn, strerror(serrno)); 1657 errno = serrno; 1658 } 1659 return (fd); 1660 } 1661 1662 /* 1663 * Get authentication data for a URL from .netrc 1664 */ 1665 int 1666 fetch_netrc_auth(struct url *url) 1667 { 1668 const char *word; 1669 int serrno; 1670 FILE *f; 1671 1672 if (url->netrcfd < 0) 1673 url->netrcfd = fetch_netrc_open(); 1674 if (url->netrcfd < 0) 1675 return (-1); 1676 if ((f = fdopen(url->netrcfd, "r")) == NULL) { 1677 serrno = errno; 1678 DEBUGF("fdopen(netrcfd): %s", strerror(errno)); 1679 close(url->netrcfd); 1680 url->netrcfd = -1; 1681 errno = serrno; 1682 return (-1); 1683 } 1684 rewind(f); 1685 DEBUGF("searching netrc for %s\n", url->host); 1686 while ((word = fetch_read_word(f)) != NULL) { 1687 if (strcmp(word, "default") == 0) { 1688 DEBUGF("using default netrc settings\n"); 1689 break; 1690 } 1691 if (strcmp(word, "machine") == 0 && 1692 (word = fetch_read_word(f)) != NULL && 1693 strcasecmp(word, url->host) == 0) { 1694 DEBUGF("using netrc settings for %s\n", word); 1695 break; 1696 } 1697 } 1698 if (word == NULL) 1699 goto ferr; 1700 while ((word = fetch_read_word(f)) != NULL) { 1701 if (strcmp(word, "login") == 0) { 1702 if ((word = fetch_read_word(f)) == NULL) 1703 goto ferr; 1704 if (snprintf(url->user, sizeof(url->user), 1705 "%s", word) > (int)sizeof(url->user)) { 1706 fetch_info("login name in .netrc is too long"); 1707 url->user[0] = '\0'; 1708 } 1709 } else if (strcmp(word, "password") == 0) { 1710 if ((word = fetch_read_word(f)) == NULL) 1711 goto ferr; 1712 if (snprintf(url->pwd, sizeof(url->pwd), 1713 "%s", word) > (int)sizeof(url->pwd)) { 1714 fetch_info("password in .netrc is too long"); 1715 url->pwd[0] = '\0'; 1716 } 1717 } else if (strcmp(word, "account") == 0) { 1718 if ((word = fetch_read_word(f)) == NULL) 1719 goto ferr; 1720 /* XXX not supported! */ 1721 } else { 1722 break; 1723 } 1724 } 1725 fclose(f); 1726 url->netrcfd = -1; 1727 return (0); 1728 ferr: 1729 serrno = errno; 1730 fclose(f); 1731 url->netrcfd = -1; 1732 errno = serrno; 1733 return (-1); 1734 } 1735 1736 /* 1737 * The no_proxy environment variable specifies a set of domains for 1738 * which the proxy should not be consulted; the contents is a comma-, 1739 * or space-separated list of domain names. A single asterisk will 1740 * override all proxy variables and no transactions will be proxied 1741 * (for compatibility with lynx and curl, see the discussion at 1742 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>). 1743 */ 1744 int 1745 fetch_no_proxy_match(const char *host) 1746 { 1747 const char *no_proxy, *p, *q; 1748 size_t h_len, d_len; 1749 1750 if ((no_proxy = getenv("NO_PROXY")) == NULL && 1751 (no_proxy = getenv("no_proxy")) == NULL) 1752 return (0); 1753 1754 /* asterisk matches any hostname */ 1755 if (strcmp(no_proxy, "*") == 0) 1756 return (1); 1757 1758 h_len = strlen(host); 1759 p = no_proxy; 1760 do { 1761 /* position p at the beginning of a domain suffix */ 1762 while (*p == ',' || isspace((unsigned char)*p)) 1763 p++; 1764 1765 /* position q at the first separator character */ 1766 for (q = p; *q; ++q) 1767 if (*q == ',' || isspace((unsigned char)*q)) 1768 break; 1769 1770 d_len = q - p; 1771 if (d_len > 0 && h_len >= d_len && 1772 strncasecmp(host + h_len - d_len, 1773 p, d_len) == 0) { 1774 /* domain name matches */ 1775 return (1); 1776 } 1777 1778 p = q + 1; 1779 } while (*q); 1780 1781 return (0); 1782 }