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 * $FreeBSD: head/lib/libfetch/common.c 358227 2020-02-21 18:21:57Z kevans 32 */ 33 34 #include <sys/cdefs.h> 35 36 #include <sys/param.h> 37 #include <sys/socket.h> 38 #include <sys/time.h> 39 #include <sys/uio.h> 40 41 #include <netinet/in.h> 42 43 #include <ctype.h> 44 #include <errno.h> 45 #include <fcntl.h> 46 #include <inttypes.h> 47 #include <netdb.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 strncpy(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 = NULL; 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_SSLv2 | SSL_OP_NO_TICKET; 1058 if (getenv("SSL_ALLOW_SSL3") == NULL) 1059 ssl_ctx_options |= SSL_OP_NO_SSLv3; 1060 if (getenv("SSL_NO_TLS1") != NULL) 1061 ssl_ctx_options |= SSL_OP_NO_TLSv1; 1062 if (getenv("SSL_NO_TLS1_1") != NULL) 1063 ssl_ctx_options |= SSL_OP_NO_TLSv1_1; 1064 if (getenv("SSL_NO_TLS1_2") != NULL) 1065 ssl_ctx_options |= SSL_OP_NO_TLSv1_2; 1066 if (verbose) 1067 fetch_info("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 #define LOCAL_CERT_FILE "/usr/local/etc/ssl/cert.pem" 1076 #define BASE_CERT_FILE "/etc/ssl/cert.pem" 1077 static int 1078 fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose) 1079 { 1080 X509_LOOKUP *crl_lookup; 1081 X509_STORE *crl_store; 1082 const char *ca_cert_file, *ca_cert_path, *crl_file; 1083 1084 if (getenv("SSL_NO_VERIFY_PEER") == NULL) { 1085 ca_cert_file = getenv("SSL_CA_CERT_FILE"); 1086 if (ca_cert_file == NULL && 1087 access(LOCAL_CERT_FILE, R_OK) == 0) 1088 ca_cert_file = LOCAL_CERT_FILE; 1089 if (ca_cert_file == NULL && 1090 access(BASE_CERT_FILE, R_OK) == 0) 1091 ca_cert_file = BASE_CERT_FILE; 1092 ca_cert_path = getenv("SSL_CA_CERT_PATH"); 1093 if (verbose) { 1094 fetch_info("Peer verification enabled"); 1095 if (ca_cert_file != NULL) 1096 fetch_info("Using CA cert file: %s", 1097 ca_cert_file); 1098 if (ca_cert_path != NULL) 1099 fetch_info("Using CA cert path: %s", 1100 ca_cert_path); 1101 if (ca_cert_file == NULL && ca_cert_path == NULL) 1102 fetch_info("Using OpenSSL default " 1103 "CA cert file and path"); 1104 } 1105 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, 1106 fetch_ssl_cb_verify_crt); 1107 if (ca_cert_file != NULL || ca_cert_path != NULL) 1108 SSL_CTX_load_verify_locations(ctx, ca_cert_file, 1109 ca_cert_path); 1110 else 1111 SSL_CTX_set_default_verify_paths(ctx); 1112 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) { 1113 if (verbose) 1114 fetch_info("Using CRL file: %s", crl_file); 1115 crl_store = SSL_CTX_get_cert_store(ctx); 1116 crl_lookup = X509_STORE_add_lookup(crl_store, 1117 X509_LOOKUP_file()); 1118 if (crl_lookup == NULL || 1119 !X509_load_crl_file(crl_lookup, crl_file, 1120 X509_FILETYPE_PEM)) { 1121 fprintf(stderr, 1122 "Could not load CRL file %s\n", 1123 crl_file); 1124 return (0); 1125 } 1126 X509_STORE_set_flags(crl_store, 1127 X509_V_FLAG_CRL_CHECK | 1128 X509_V_FLAG_CRL_CHECK_ALL); 1129 } 1130 } 1131 return (1); 1132 } 1133 1134 /* 1135 * Configure client certificate based on environment. 1136 */ 1137 static int 1138 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose) 1139 { 1140 const char *client_cert_file, *client_key_file; 1141 1142 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) { 1143 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ? 1144 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file; 1145 if (verbose) { 1146 fetch_info("Using client cert file: %s", 1147 client_cert_file); 1148 fetch_info("Using client key file: %s", 1149 client_key_file); 1150 } 1151 if (SSL_CTX_use_certificate_chain_file(ctx, 1152 client_cert_file) != 1) { 1153 fprintf(stderr, 1154 "Could not load client certificate %s\n", 1155 client_cert_file); 1156 return (0); 1157 } 1158 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file, 1159 SSL_FILETYPE_PEM) != 1) { 1160 fprintf(stderr, 1161 "Could not load client key %s\n", 1162 client_key_file); 1163 return (0); 1164 } 1165 } 1166 return (1); 1167 } 1168 1169 /* 1170 * Callback for SSL certificate verification, this is called on server 1171 * cert verification. It takes no decision, but informs the user in case 1172 * verification failed. 1173 */ 1174 int 1175 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx) 1176 { 1177 X509 *crt; 1178 X509_NAME *name; 1179 char *str; 1180 1181 str = NULL; 1182 if (!verified) { 1183 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL && 1184 (name = X509_get_subject_name(crt)) != NULL) 1185 str = X509_NAME_oneline(name, 0, 0); 1186 fprintf(stderr, "Certificate verification failed for %s\n", 1187 str != NULL ? str : "no relevant certificate"); 1188 OPENSSL_free(str); 1189 } 1190 return (verified); 1191 } 1192 1193 #endif 1194 1195 /* 1196 * Enable SSL on a connection. 1197 */ 1198 int 1199 fetch_ssl(conn_t *conn, const struct url *URL, int verbose) 1200 { 1201 #ifdef WITH_SSL 1202 int ret, ssl_err; 1203 X509_NAME *name; 1204 char *str; 1205 1206 /* Init the SSL library and context */ 1207 if (!SSL_library_init()){ 1208 fprintf(stderr, "SSL library init failed\n"); 1209 return (-1); 1210 } 1211 1212 SSL_load_error_strings(); 1213 1214 conn->ssl_meth = SSLv23_client_method(); 1215 conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth); 1216 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY); 1217 1218 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose); 1219 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose)) 1220 return (-1); 1221 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose)) 1222 return (-1); 1223 1224 conn->ssl = SSL_new(conn->ssl_ctx); 1225 if (conn->ssl == NULL) { 1226 fprintf(stderr, "SSL context creation failed\n"); 1227 return (-1); 1228 } 1229 SSL_set_fd(conn->ssl, conn->sd); 1230 1231 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) 1232 if (!SSL_set_tlsext_host_name(conn->ssl, 1233 __DECONST(struct url *, URL)->host)) { 1234 fprintf(stderr, 1235 "TLS server name indication extension failed for host %s\n", 1236 URL->host); 1237 return (-1); 1238 } 1239 #endif 1240 while ((ret = SSL_connect(conn->ssl)) == -1) { 1241 ssl_err = SSL_get_error(conn->ssl, ret); 1242 if (ssl_err != SSL_ERROR_WANT_READ && 1243 ssl_err != SSL_ERROR_WANT_WRITE) { 1244 ERR_print_errors_fp(stderr); 1245 return (-1); 1246 } 1247 } 1248 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl); 1249 1250 if (conn->ssl_cert == NULL) { 1251 fprintf(stderr, "No server SSL certificate\n"); 1252 return (-1); 1253 } 1254 1255 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) { 1256 if (verbose) 1257 fetch_info("Verify hostname"); 1258 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) { 1259 fprintf(stderr, 1260 "SSL certificate subject doesn't match host %s\n", 1261 URL->host); 1262 return (-1); 1263 } 1264 } 1265 1266 if (verbose) { 1267 fetch_info("%s connection established using %s", 1268 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl)); 1269 name = X509_get_subject_name(conn->ssl_cert); 1270 str = X509_NAME_oneline(name, 0, 0); 1271 fetch_info("Certificate subject: %s", str); 1272 OPENSSL_free(str); 1273 name = X509_get_issuer_name(conn->ssl_cert); 1274 str = X509_NAME_oneline(name, 0, 0); 1275 fetch_info("Certificate issuer: %s", str); 1276 OPENSSL_free(str); 1277 } 1278 1279 return (0); 1280 #else 1281 (void)conn; 1282 (void)verbose; 1283 (void)URL; 1284 fprintf(stderr, "SSL support disabled\n"); 1285 return (-1); 1286 #endif 1287 } 1288 1289 #define FETCH_READ_WAIT -2 1290 #define FETCH_READ_ERROR -1 1291 #define FETCH_READ_DONE 0 1292 1293 #ifdef WITH_SSL 1294 static ssize_t 1295 fetch_ssl_read(SSL *ssl, char *buf, size_t len) 1296 { 1297 ssize_t rlen; 1298 int ssl_err; 1299 1300 rlen = SSL_read(ssl, buf, len); 1301 if (rlen < 0) { 1302 ssl_err = SSL_get_error(ssl, rlen); 1303 if (ssl_err == SSL_ERROR_WANT_READ || 1304 ssl_err == SSL_ERROR_WANT_WRITE) { 1305 return (FETCH_READ_WAIT); 1306 } else { 1307 ERR_print_errors_fp(stderr); 1308 return (FETCH_READ_ERROR); 1309 } 1310 } 1311 return (rlen); 1312 } 1313 #endif 1314 1315 static ssize_t 1316 fetch_socket_read(int sd, char *buf, size_t len) 1317 { 1318 ssize_t rlen; 1319 1320 rlen = read(sd, buf, len); 1321 if (rlen < 0) { 1322 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls)) 1323 return (FETCH_READ_WAIT); 1324 else 1325 return (FETCH_READ_ERROR); 1326 } 1327 return (rlen); 1328 } 1329 1330 /* 1331 * Read a character from a connection w/ timeout 1332 */ 1333 ssize_t 1334 fetch_read(conn_t *conn, char *buf, size_t len) 1335 { 1336 struct timeval now, timeout, delta; 1337 struct pollfd pfd; 1338 ssize_t rlen; 1339 int deltams; 1340 1341 if (fetchTimeout > 0) { 1342 gettimeofday(&timeout, NULL); 1343 timeout.tv_sec += fetchTimeout; 1344 } 1345 1346 deltams = INFTIM; 1347 memset(&pfd, 0, sizeof pfd); 1348 pfd.fd = conn->sd; 1349 pfd.events = POLLIN | POLLERR; 1350 1351 for (;;) { 1352 /* 1353 * The socket is non-blocking. Instead of the canonical 1354 * poll() -> read(), we do the following: 1355 * 1356 * 1) call read() or SSL_read(). 1357 * 2) if we received some data, return it. 1358 * 3) if an error occurred, return -1. 1359 * 4) if read() or SSL_read() signaled EOF, return. 1360 * 5) if we did not receive any data but we're not at EOF, 1361 * call poll(). 1362 * 1363 * In the SSL case, this is necessary because if we 1364 * receive a close notification, we have to call 1365 * SSL_read() one additional time after we've read 1366 * everything we received. 1367 * 1368 * In the non-SSL case, it may improve performance (very 1369 * slightly) when reading small amounts of data. 1370 */ 1371 #ifdef WITH_SSL 1372 if (conn->ssl != NULL) 1373 rlen = fetch_ssl_read(conn->ssl, buf, len); 1374 else 1375 #endif 1376 rlen = fetch_socket_read(conn->sd, buf, len); 1377 if (rlen >= 0) { 1378 break; 1379 } else if (rlen == FETCH_READ_ERROR) { 1380 fetch_syserr(); 1381 return (-1); 1382 } 1383 // assert(rlen == FETCH_READ_WAIT); 1384 if (fetchTimeout > 0) { 1385 gettimeofday(&now, NULL); 1386 if (!timercmp(&timeout, &now, >)) { 1387 errno = ETIMEDOUT; 1388 fetch_syserr(); 1389 return (-1); 1390 } 1391 timersub(&timeout, &now, &delta); 1392 deltams = delta.tv_sec * 1000 + 1393 delta.tv_usec / 1000;; 1394 } 1395 errno = 0; 1396 pfd.revents = 0; 1397 if (poll(&pfd, 1, deltams) < 0) { 1398 if (errno == EINTR && fetchRestartCalls) 1399 continue; 1400 fetch_syserr(); 1401 return (-1); 1402 } 1403 } 1404 return (rlen); 1405 } 1406 1407 1408 /* 1409 * Read a line of text from a connection w/ timeout 1410 */ 1411 #define MIN_BUF_SIZE 1024 1412 1413 int 1414 fetch_getln(conn_t *conn) 1415 { 1416 char *tmp; 1417 size_t tmpsize; 1418 ssize_t len; 1419 char c; 1420 1421 if (conn->buf == NULL) { 1422 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) { 1423 errno = ENOMEM; 1424 return (-1); 1425 } 1426 conn->bufsize = MIN_BUF_SIZE; 1427 } 1428 1429 conn->buf[0] = '\0'; 1430 conn->buflen = 0; 1431 1432 do { 1433 len = fetch_read(conn, &c, 1); 1434 if (len == -1) 1435 return (-1); 1436 if (len == 0) 1437 break; 1438 conn->buf[conn->buflen++] = c; 1439 if (conn->buflen == conn->bufsize) { 1440 tmp = conn->buf; 1441 tmpsize = conn->bufsize * 2 + 1; 1442 if ((tmp = realloc(tmp, tmpsize)) == NULL) { 1443 errno = ENOMEM; 1444 return (-1); 1445 } 1446 conn->buf = tmp; 1447 conn->bufsize = tmpsize; 1448 } 1449 } while (c != '\n'); 1450 1451 conn->buf[conn->buflen] = '\0'; 1452 DEBUGF("<<< %s", conn->buf); 1453 return (0); 1454 } 1455 1456 1457 /* 1458 * Write to a connection w/ timeout 1459 */ 1460 ssize_t 1461 fetch_write(conn_t *conn, const char *buf, size_t len) 1462 { 1463 struct iovec iov; 1464 1465 iov.iov_base = __DECONST(char *, buf); 1466 iov.iov_len = len; 1467 return fetch_writev(conn, &iov, 1); 1468 } 1469 1470 /* 1471 * Write a vector to a connection w/ timeout 1472 * Note: can modify the iovec. 1473 */ 1474 ssize_t 1475 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt) 1476 { 1477 struct timeval now, timeout, delta; 1478 struct pollfd pfd; 1479 ssize_t wlen, total; 1480 int deltams; 1481 1482 memset(&pfd, 0, sizeof pfd); 1483 if (fetchTimeout) { 1484 pfd.fd = conn->sd; 1485 pfd.events = POLLOUT | POLLERR; 1486 gettimeofday(&timeout, NULL); 1487 timeout.tv_sec += fetchTimeout; 1488 } 1489 1490 total = 0; 1491 while (iovcnt > 0) { 1492 while (fetchTimeout && pfd.revents == 0) { 1493 gettimeofday(&now, NULL); 1494 if (!timercmp(&timeout, &now, >)) { 1495 errno = ETIMEDOUT; 1496 fetch_syserr(); 1497 return (-1); 1498 } 1499 timersub(&timeout, &now, &delta); 1500 deltams = delta.tv_sec * 1000 + 1501 delta.tv_usec / 1000; 1502 errno = 0; 1503 pfd.revents = 0; 1504 if (poll(&pfd, 1, deltams) < 0) { 1505 /* POSIX compliance */ 1506 if (errno == EAGAIN) 1507 continue; 1508 if (errno == EINTR && fetchRestartCalls) 1509 continue; 1510 return (-1); 1511 } 1512 } 1513 errno = 0; 1514 #ifdef WITH_SSL 1515 if (conn->ssl != NULL) 1516 wlen = SSL_write(conn->ssl, 1517 iov->iov_base, iov->iov_len); 1518 else 1519 #endif 1520 wlen = writev(conn->sd, iov, iovcnt); 1521 if (wlen == 0) { 1522 /* we consider a short write a failure */ 1523 /* XXX perhaps we shouldn't in the SSL case */ 1524 errno = EPIPE; 1525 fetch_syserr(); 1526 return (-1); 1527 } 1528 if (wlen < 0) { 1529 if (errno == EINTR && fetchRestartCalls) 1530 continue; 1531 return (-1); 1532 } 1533 total += wlen; 1534 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) { 1535 wlen -= iov->iov_len; 1536 iov++; 1537 iovcnt--; 1538 } 1539 if (iovcnt > 0) { 1540 iov->iov_len -= wlen; 1541 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen; 1542 } 1543 } 1544 return (total); 1545 } 1546 1547 1548 /* 1549 * Write a line of text to a connection w/ timeout 1550 */ 1551 int 1552 fetch_putln(conn_t *conn, const char *str, size_t len) 1553 { 1554 struct iovec iov[2]; 1555 int ret; 1556 1557 DEBUGF(">>> %s\n", str); 1558 iov[0].iov_base = __DECONST(char *, str); 1559 iov[0].iov_len = len; 1560 iov[1].iov_base = __DECONST(char *, ENDL); 1561 iov[1].iov_len = sizeof(ENDL); 1562 if (len == 0) 1563 ret = fetch_writev(conn, &iov[1], 1); 1564 else 1565 ret = fetch_writev(conn, iov, 2); 1566 if (ret == -1) 1567 return (-1); 1568 return (0); 1569 } 1570 1571 1572 /* 1573 * Close connection 1574 */ 1575 int 1576 fetch_close(conn_t *conn) 1577 { 1578 int ret; 1579 1580 if (--conn->ref > 0) 1581 return (0); 1582 #ifdef WITH_SSL 1583 if (conn->ssl) { 1584 SSL_shutdown(conn->ssl); 1585 SSL_set_connect_state(conn->ssl); 1586 SSL_free(conn->ssl); 1587 conn->ssl = NULL; 1588 } 1589 if (conn->ssl_ctx) { 1590 SSL_CTX_free(conn->ssl_ctx); 1591 conn->ssl_ctx = NULL; 1592 } 1593 if (conn->ssl_cert) { 1594 X509_free(conn->ssl_cert); 1595 conn->ssl_cert = NULL; 1596 } 1597 #endif 1598 ret = close(conn->sd); 1599 free(conn->buf); 1600 free(conn); 1601 return (ret); 1602 } 1603 1604 1605 /*** Directory-related utility functions *************************************/ 1606 1607 int 1608 fetch_add_entry(struct url_ent **p, int *size, int *len, 1609 const char *name, struct url_stat *us) 1610 { 1611 struct url_ent *tmp; 1612 1613 if (*p == NULL) { 1614 *size = 0; 1615 *len = 0; 1616 } 1617 1618 if (*len >= *size - 1) { 1619 tmp = reallocarray(*p, *size * 2 + 1, sizeof(**p)); 1620 if (tmp == NULL) { 1621 errno = ENOMEM; 1622 fetch_syserr(); 1623 return (-1); 1624 } 1625 *size = (*size * 2 + 1); 1626 *p = tmp; 1627 } 1628 1629 tmp = *p + *len; 1630 snprintf(tmp->name, PATH_MAX, "%s", name); 1631 memcpy(&tmp->stat, us, sizeof(*us)); 1632 1633 (*len)++; 1634 (++tmp)->name[0] = 0; 1635 1636 return (0); 1637 } 1638 1639 1640 /*** Authentication-related utility functions ********************************/ 1641 1642 static const char * 1643 fetch_read_word(FILE *f) 1644 { 1645 static char word[1024]; 1646 1647 if (fscanf(f, " %1023s ", word) != 1) 1648 return (NULL); 1649 return (word); 1650 } 1651 1652 static int 1653 fetch_netrc_open(void) 1654 { 1655 struct passwd *pwd; 1656 char fn[PATH_MAX]; 1657 const char *p; 1658 int fd, serrno; 1659 1660 if ((p = getenv("NETRC")) != NULL) { 1661 DEBUGF("NETRC=%s\n", p); 1662 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) { 1663 fetch_info("$NETRC specifies a file name " 1664 "longer than PATH_MAX"); 1665 return (-1); 1666 } 1667 } else { 1668 if ((p = getenv("HOME")) == NULL) { 1669 if ((pwd = getpwuid(getuid())) == NULL || 1670 (p = pwd->pw_dir) == NULL) 1671 return (-1); 1672 } 1673 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn)) 1674 return (-1); 1675 } 1676 1677 if ((fd = open(fn, O_RDONLY)) < 0) { 1678 serrno = errno; 1679 DEBUGF("%s: %s\n", fn, strerror(serrno)); 1680 errno = serrno; 1681 } 1682 return (fd); 1683 } 1684 1685 /* 1686 * Get authentication data for a URL from .netrc 1687 */ 1688 int 1689 fetch_netrc_auth(struct url *url) 1690 { 1691 const char *word; 1692 int serrno; 1693 FILE *f; 1694 1695 if (url->netrcfd < 0) 1696 url->netrcfd = fetch_netrc_open(); 1697 if (url->netrcfd < 0) 1698 return (-1); 1699 if ((f = fdopen(url->netrcfd, "r")) == NULL) { 1700 serrno = errno; 1701 DEBUGF("fdopen(netrcfd): %s", strerror(errno)); 1702 close(url->netrcfd); 1703 url->netrcfd = -1; 1704 errno = serrno; 1705 return (-1); 1706 } 1707 rewind(f); 1708 DEBUGF("searching netrc for %s\n", url->host); 1709 while ((word = fetch_read_word(f)) != NULL) { 1710 if (strcmp(word, "default") == 0) { 1711 DEBUGF("using default netrc settings\n"); 1712 break; 1713 } 1714 if (strcmp(word, "machine") == 0 && 1715 (word = fetch_read_word(f)) != NULL && 1716 strcasecmp(word, url->host) == 0) { 1717 DEBUGF("using netrc settings for %s\n", word); 1718 break; 1719 } 1720 } 1721 if (word == NULL) 1722 goto ferr; 1723 while ((word = fetch_read_word(f)) != NULL) { 1724 if (strcmp(word, "login") == 0) { 1725 if ((word = fetch_read_word(f)) == NULL) 1726 goto ferr; 1727 if (snprintf(url->user, sizeof(url->user), 1728 "%s", word) > (int)sizeof(url->user)) { 1729 fetch_info("login name in .netrc is too long"); 1730 url->user[0] = '\0'; 1731 } 1732 } else if (strcmp(word, "password") == 0) { 1733 if ((word = fetch_read_word(f)) == NULL) 1734 goto ferr; 1735 if (snprintf(url->pwd, sizeof(url->pwd), 1736 "%s", word) > (int)sizeof(url->pwd)) { 1737 fetch_info("password in .netrc is too long"); 1738 url->pwd[0] = '\0'; 1739 } 1740 } else if (strcmp(word, "account") == 0) { 1741 if ((word = fetch_read_word(f)) == NULL) 1742 goto ferr; 1743 /* XXX not supported! */ 1744 } else { 1745 break; 1746 } 1747 } 1748 fclose(f); 1749 url->netrcfd = -1; 1750 return (0); 1751 ferr: 1752 serrno = errno; 1753 fclose(f); 1754 url->netrcfd = -1; 1755 errno = serrno; 1756 return (-1); 1757 } 1758 1759 /* 1760 * The no_proxy environment variable specifies a set of domains for 1761 * which the proxy should not be consulted; the contents is a comma-, 1762 * or space-separated list of domain names. A single asterisk will 1763 * override all proxy variables and no transactions will be proxied 1764 * (for compatibility with lynx and curl, see the discussion at 1765 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>). 1766 */ 1767 int 1768 fetch_no_proxy_match(const char *host) 1769 { 1770 const char *no_proxy, *p, *q; 1771 size_t h_len, d_len; 1772 1773 if ((no_proxy = getenv("NO_PROXY")) == NULL && 1774 (no_proxy = getenv("no_proxy")) == NULL) 1775 return (0); 1776 1777 /* asterisk matches any hostname */ 1778 if (strcmp(no_proxy, "*") == 0) 1779 return (1); 1780 1781 h_len = strlen(host); 1782 p = no_proxy; 1783 do { 1784 /* position p at the beginning of a domain suffix */ 1785 while (*p == ',' || isspace((unsigned char)*p)) 1786 p++; 1787 1788 /* position q at the first separator character */ 1789 for (q = p; *q; ++q) 1790 if (*q == ',' || isspace((unsigned char)*q)) 1791 break; 1792 1793 d_len = q - p; 1794 if (d_len > 0 && h_len >= d_len && 1795 strncasecmp(host + h_len - d_len, 1796 p, d_len) == 0) { 1797 /* domain name matches */ 1798 return (1); 1799 } 1800 1801 p = q + 1; 1802 } while (*q); 1803 1804 return (0); 1805 } 1806