1 /*- 2 * Copyright (c) 1998-2014 Dag-Erling Smørgrav 3 * Copyright (c) 2013 Michael Gmelin <freebsd@grem.de> 4 * All rights reserved. 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer 11 * in this position and unchanged. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include <sys/cdefs.h> 31 __FBSDID("$FreeBSD$"); 32 33 #include <sys/param.h> 34 #include <sys/socket.h> 35 #include <sys/time.h> 36 #include <sys/uio.h> 37 38 #include <netinet/in.h> 39 40 #include <ctype.h> 41 #include <errno.h> 42 #include <fcntl.h> 43 #include <netdb.h> 44 #include <poll.h> 45 #include <pwd.h> 46 #include <stdarg.h> 47 #include <stdlib.h> 48 #include <stdio.h> 49 #include <string.h> 50 #include <unistd.h> 51 52 #ifdef WITH_SSL 53 #include <openssl/x509v3.h> 54 #endif 55 56 #include "fetch.h" 57 #include "common.h" 58 59 60 /*** Local data **************************************************************/ 61 62 /* 63 * Error messages for resolver errors 64 */ 65 static struct fetcherr netdb_errlist[] = { 66 #ifdef EAI_NODATA 67 { EAI_NODATA, FETCH_RESOLV, "Host not found" }, 68 #endif 69 { EAI_AGAIN, FETCH_TEMP, "Transient resolver failure" }, 70 { EAI_FAIL, FETCH_RESOLV, "Non-recoverable resolver failure" }, 71 { EAI_NONAME, FETCH_RESOLV, "No address record" }, 72 { -1, FETCH_UNKNOWN, "Unknown resolver error" } 73 }; 74 75 /* End-of-Line */ 76 static const char ENDL[2] = "\r\n"; 77 78 79 /*** Error-reporting functions ***********************************************/ 80 81 /* 82 * Map error code to string 83 */ 84 static struct fetcherr * 85 fetch_finderr(struct fetcherr *p, int e) 86 { 87 while (p->num != -1 && p->num != e) 88 p++; 89 return (p); 90 } 91 92 /* 93 * Set error code 94 */ 95 void 96 fetch_seterr(struct fetcherr *p, int e) 97 { 98 p = fetch_finderr(p, e); 99 fetchLastErrCode = p->cat; 100 snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string); 101 } 102 103 /* 104 * Set error code according to errno 105 */ 106 void 107 fetch_syserr(void) 108 { 109 switch (errno) { 110 case 0: 111 fetchLastErrCode = FETCH_OK; 112 break; 113 case EPERM: 114 case EACCES: 115 case EROFS: 116 case EAUTH: 117 case ENEEDAUTH: 118 fetchLastErrCode = FETCH_AUTH; 119 break; 120 case ENOENT: 121 case EISDIR: /* XXX */ 122 fetchLastErrCode = FETCH_UNAVAIL; 123 break; 124 case ENOMEM: 125 fetchLastErrCode = FETCH_MEMORY; 126 break; 127 case EBUSY: 128 case EAGAIN: 129 fetchLastErrCode = FETCH_TEMP; 130 break; 131 case EEXIST: 132 fetchLastErrCode = FETCH_EXISTS; 133 break; 134 case ENOSPC: 135 fetchLastErrCode = FETCH_FULL; 136 break; 137 case EADDRINUSE: 138 case EADDRNOTAVAIL: 139 case ENETDOWN: 140 case ENETUNREACH: 141 case ENETRESET: 142 case EHOSTUNREACH: 143 fetchLastErrCode = FETCH_NETWORK; 144 break; 145 case ECONNABORTED: 146 case ECONNRESET: 147 fetchLastErrCode = FETCH_ABORT; 148 break; 149 case ETIMEDOUT: 150 fetchLastErrCode = FETCH_TIMEOUT; 151 break; 152 case ECONNREFUSED: 153 case EHOSTDOWN: 154 fetchLastErrCode = FETCH_DOWN; 155 break; 156 default: 157 fetchLastErrCode = FETCH_UNKNOWN; 158 } 159 snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno)); 160 } 161 162 163 /* 164 * Emit status message 165 */ 166 void 167 fetch_info(const char *fmt, ...) 168 { 169 va_list ap; 170 171 va_start(ap, fmt); 172 vfprintf(stderr, fmt, ap); 173 va_end(ap); 174 fputc('\n', stderr); 175 } 176 177 178 /*** Network-related utility functions ***************************************/ 179 180 /* 181 * Return the default port for a scheme 182 */ 183 int 184 fetch_default_port(const char *scheme) 185 { 186 struct servent *se; 187 188 if ((se = getservbyname(scheme, "tcp")) != NULL) 189 return (ntohs(se->s_port)); 190 if (strcasecmp(scheme, SCHEME_FTP) == 0) 191 return (FTP_DEFAULT_PORT); 192 if (strcasecmp(scheme, SCHEME_HTTP) == 0) 193 return (HTTP_DEFAULT_PORT); 194 return (0); 195 } 196 197 /* 198 * Return the default proxy port for a scheme 199 */ 200 int 201 fetch_default_proxy_port(const char *scheme) 202 { 203 if (strcasecmp(scheme, SCHEME_FTP) == 0) 204 return (FTP_DEFAULT_PROXY_PORT); 205 if (strcasecmp(scheme, SCHEME_HTTP) == 0) 206 return (HTTP_DEFAULT_PROXY_PORT); 207 return (0); 208 } 209 210 211 /* 212 * Create a connection for an existing descriptor. 213 */ 214 conn_t * 215 fetch_reopen(int sd) 216 { 217 conn_t *conn; 218 int opt = 1; 219 220 /* allocate and fill connection structure */ 221 if ((conn = calloc(1, sizeof(*conn))) == NULL) 222 return (NULL); 223 fcntl(sd, F_SETFD, FD_CLOEXEC); 224 setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt); 225 conn->sd = sd; 226 ++conn->ref; 227 return (conn); 228 } 229 230 231 /* 232 * Bump a connection's reference count. 233 */ 234 conn_t * 235 fetch_ref(conn_t *conn) 236 { 237 238 ++conn->ref; 239 return (conn); 240 } 241 242 243 /* 244 * Bind a socket to a specific local address 245 */ 246 int 247 fetch_bind(int sd, int af, const char *addr) 248 { 249 struct addrinfo hints, *res, *res0; 250 int err; 251 252 memset(&hints, 0, sizeof(hints)); 253 hints.ai_family = af; 254 hints.ai_socktype = SOCK_STREAM; 255 hints.ai_protocol = 0; 256 if ((err = getaddrinfo(addr, NULL, &hints, &res0)) != 0) 257 return (-1); 258 for (res = res0; res; res = res->ai_next) 259 if (bind(sd, res->ai_addr, res->ai_addrlen) == 0) { 260 freeaddrinfo(res0); 261 return (0); 262 } 263 freeaddrinfo(res0); 264 return (-1); 265 } 266 267 268 /* 269 * Establish a TCP connection to the specified port on the specified host. 270 */ 271 conn_t * 272 fetch_connect(const char *host, int port, int af, int verbose) 273 { 274 conn_t *conn; 275 char pbuf[10]; 276 const char *bindaddr; 277 struct addrinfo hints, *res, *res0; 278 int sd, err; 279 280 DEBUG(fprintf(stderr, "---> %s:%d\n", host, port)); 281 282 if (verbose) 283 fetch_info("looking up %s", host); 284 285 /* look up host name and set up socket address structure */ 286 snprintf(pbuf, sizeof(pbuf), "%d", port); 287 memset(&hints, 0, sizeof(hints)); 288 hints.ai_family = af; 289 hints.ai_socktype = SOCK_STREAM; 290 hints.ai_protocol = 0; 291 if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) { 292 netdb_seterr(err); 293 return (NULL); 294 } 295 bindaddr = getenv("FETCH_BIND_ADDRESS"); 296 297 if (verbose) 298 fetch_info("connecting to %s:%d", host, port); 299 300 /* try to connect */ 301 for (sd = -1, res = res0; res; sd = -1, res = res->ai_next) { 302 if ((sd = socket(res->ai_family, res->ai_socktype, 303 res->ai_protocol)) == -1) 304 continue; 305 if (bindaddr != NULL && *bindaddr != '\0' && 306 fetch_bind(sd, res->ai_family, bindaddr) != 0) { 307 fetch_info("failed to bind to '%s'", bindaddr); 308 close(sd); 309 continue; 310 } 311 if (connect(sd, res->ai_addr, res->ai_addrlen) == 0 && 312 fcntl(sd, F_SETFL, O_NONBLOCK) == 0) 313 break; 314 close(sd); 315 } 316 freeaddrinfo(res0); 317 if (sd == -1) { 318 fetch_syserr(); 319 return (NULL); 320 } 321 322 if ((conn = fetch_reopen(sd)) == NULL) { 323 fetch_syserr(); 324 close(sd); 325 } 326 return (conn); 327 } 328 329 #ifdef WITH_SSL 330 /* 331 * Convert characters A-Z to lowercase (intentionally avoid any locale 332 * specific conversions). 333 */ 334 static char 335 fetch_ssl_tolower(char in) 336 { 337 if (in >= 'A' && in <= 'Z') 338 return (in + 32); 339 else 340 return (in); 341 } 342 343 /* 344 * isalpha implementation that intentionally avoids any locale specific 345 * conversions. 346 */ 347 static int 348 fetch_ssl_isalpha(char in) 349 { 350 return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z')); 351 } 352 353 /* 354 * Check if passed hostnames a and b are equal. 355 */ 356 static int 357 fetch_ssl_hname_equal(const char *a, size_t alen, const char *b, 358 size_t blen) 359 { 360 size_t i; 361 362 if (alen != blen) 363 return (0); 364 for (i = 0; i < alen; ++i) { 365 if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i])) 366 return (0); 367 } 368 return (1); 369 } 370 371 /* 372 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9 373 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha- 374 * numeric characters. Double hyphens (like they're found in IDN a-labels 375 * 'xn--') are not allowed. Empty labels are invalid. 376 */ 377 static int 378 fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok) 379 { 380 size_t i; 381 382 if (!len || l[0] == '-' || l[len-1] == '-') 383 return (0); 384 for (i = 0; i < len; ++i) { 385 if (!isdigit(l[i]) && 386 !fetch_ssl_isalpha(l[i]) && 387 !(l[i] == '*' && wcok) && 388 !(l[i] == '-' && l[i - 1] != '-')) 389 return (0); 390 } 391 return (1); 392 } 393 394 /* 395 * Check if host name consists only of numbers. This might indicate an IP 396 * address, which is not a good idea for CN wildcard comparison. 397 */ 398 static int 399 fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len) 400 { 401 size_t i; 402 403 for (i = 0; i < len; ++i) { 404 if (!((hostname[i] >= '0' && hostname[i] <= '9') || 405 hostname[i] == '.')) 406 return (0); 407 } 408 return (1); 409 } 410 411 /* 412 * Check if the host name h passed matches the pattern passed in m which 413 * is usually part of subjectAltName or CN of a certificate presented to 414 * the client. This includes wildcard matching. The algorithm is based on 415 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280. 416 */ 417 static int 418 fetch_ssl_hname_match(const char *h, size_t hlen, const char *m, 419 size_t mlen) 420 { 421 int delta, hdotidx, mdot1idx, wcidx; 422 const char *hdot, *mdot1, *mdot2; 423 const char *wc; /* wildcard */ 424 425 if (!(h && *h && m && *m)) 426 return (0); 427 if ((wc = strnstr(m, "*", mlen)) == NULL) 428 return (fetch_ssl_hname_equal(h, hlen, m, mlen)); 429 wcidx = wc - m; 430 /* hostname should not be just dots and numbers */ 431 if (fetch_ssl_hname_is_only_numbers(h, hlen)) 432 return (0); 433 /* only one wildcard allowed in pattern */ 434 if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL) 435 return (0); 436 /* 437 * there must be at least two more domain labels and 438 * wildcard has to be in the leftmost label (RFC6125) 439 */ 440 mdot1 = strnstr(m, ".", mlen); 441 if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4) 442 return (0); 443 mdot1idx = mdot1 - m; 444 mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1); 445 if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2) 446 return (0); 447 /* hostname must contain a dot and not be the 1st char */ 448 hdot = strnstr(h, ".", hlen); 449 if (hdot == NULL || hdot == h) 450 return (0); 451 hdotidx = hdot - h; 452 /* 453 * host part of hostname must be at least as long as 454 * pattern it's supposed to match 455 */ 456 if (hdotidx < mdot1idx) 457 return (0); 458 /* 459 * don't allow wildcards in non-traditional domain names 460 * (IDN, A-label, U-label...) 461 */ 462 if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) || 463 !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1)) 464 return (0); 465 /* match domain part (part after first dot) */ 466 if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1, 467 mlen - mdot1idx)) 468 return (0); 469 /* match part left of wildcard */ 470 if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx)) 471 return (0); 472 /* match part right of wildcard */ 473 delta = mdot1idx - wcidx - 1; 474 if (!fetch_ssl_hname_equal(hdot - delta, delta, 475 mdot1 - delta, delta)) 476 return (0); 477 /* all tests succeeded, it's a match */ 478 return (1); 479 } 480 481 /* 482 * Get numeric host address info - returns NULL if host was not an IP 483 * address. The caller is responsible for deallocation using 484 * freeaddrinfo(3). 485 */ 486 static struct addrinfo * 487 fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len) 488 { 489 struct addrinfo hints, *res; 490 char *host; 491 492 host = (char *)malloc(len + 1); 493 memcpy(host, hostname, len); 494 host[len] = '\0'; 495 memset(&hints, 0, sizeof(hints)); 496 hints.ai_family = PF_UNSPEC; 497 hints.ai_socktype = SOCK_STREAM; 498 hints.ai_protocol = 0; 499 hints.ai_flags = AI_NUMERICHOST; 500 /* port is not relevant for this purpose */ 501 if (getaddrinfo(host, "443", &hints, &res) != 0) 502 res = NULL; 503 free(host); 504 return res; 505 } 506 507 /* 508 * Compare ip address in addrinfo with address passes. 509 */ 510 static int 511 fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost, 512 size_t rhostlen) 513 { 514 const void *left; 515 516 if (lhost->ai_family == AF_INET && rhostlen == 4) { 517 left = (void *)&((struct sockaddr_in*)(void *) 518 lhost->ai_addr)->sin_addr.s_addr; 519 #ifdef INET6 520 } else if (lhost->ai_family == AF_INET6 && rhostlen == 16) { 521 left = (void *)&((struct sockaddr_in6 *)(void *) 522 lhost->ai_addr)->sin6_addr; 523 #endif 524 } else 525 return (0); 526 return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0); 527 } 528 529 /* 530 * Compare ip address in addrinfo with host passed. If host is not an IP 531 * address, comparison will fail. 532 */ 533 static int 534 fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r, 535 size_t rlen) 536 { 537 struct addrinfo *raddr; 538 int ret; 539 char *rip; 540 541 ret = 0; 542 if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL) 543 return 0; /* not a numeric host */ 544 545 if (laddr->ai_family == raddr->ai_family) { 546 if (laddr->ai_family == AF_INET) { 547 rip = (char *)&((struct sockaddr_in *)(void *) 548 raddr->ai_addr)->sin_addr.s_addr; 549 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4); 550 #ifdef INET6 551 } else if (laddr->ai_family == AF_INET6) { 552 rip = (char *)&((struct sockaddr_in6 *)(void *) 553 raddr->ai_addr)->sin6_addr; 554 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16); 555 #endif 556 } 557 558 } 559 freeaddrinfo(raddr); 560 return (ret); 561 } 562 563 /* 564 * Verify server certificate by subjectAltName. 565 */ 566 static int 567 fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames, 568 const char *host, struct addrinfo *ip) 569 { 570 const GENERAL_NAME *name; 571 size_t nslen; 572 int i; 573 const char *ns; 574 575 for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) { 576 #if OPENSSL_VERSION_NUMBER < 0x10000000L 577 /* 578 * This is a workaround, since the following line causes 579 * alignment issues in clang: 580 * name = sk_GENERAL_NAME_value(altnames, i); 581 * OpenSSL explicitly warns not to use those macros 582 * directly, but there isn't much choice (and there 583 * shouldn't be any ill side effects) 584 */ 585 name = (GENERAL_NAME *)SKM_sk_value(void, altnames, i); 586 #else 587 name = sk_GENERAL_NAME_value(altnames, i); 588 #endif 589 ns = (const char *)ASN1_STRING_data(name->d.ia5); 590 nslen = (size_t)ASN1_STRING_length(name->d.ia5); 591 592 if (name->type == GEN_DNS && ip == NULL && 593 fetch_ssl_hname_match(host, strlen(host), ns, nslen)) 594 return (1); 595 else if (name->type == GEN_IPADD && ip != NULL && 596 fetch_ssl_ipaddr_match_bin(ip, ns, nslen)) 597 return (1); 598 } 599 return (0); 600 } 601 602 /* 603 * Verify server certificate by CN. 604 */ 605 static int 606 fetch_ssl_verify_cn(X509_NAME *subject, const char *host, 607 struct addrinfo *ip) 608 { 609 ASN1_STRING *namedata; 610 X509_NAME_ENTRY *nameentry; 611 int cnlen, lastpos, loc, ret; 612 unsigned char *cn; 613 614 ret = 0; 615 lastpos = -1; 616 loc = -1; 617 cn = NULL; 618 /* get most specific CN (last entry in list) and compare */ 619 while ((lastpos = X509_NAME_get_index_by_NID(subject, 620 NID_commonName, lastpos)) != -1) 621 loc = lastpos; 622 623 if (loc > -1) { 624 nameentry = X509_NAME_get_entry(subject, loc); 625 namedata = X509_NAME_ENTRY_get_data(nameentry); 626 cnlen = ASN1_STRING_to_UTF8(&cn, namedata); 627 if (ip == NULL && 628 fetch_ssl_hname_match(host, strlen(host), cn, cnlen)) 629 ret = 1; 630 else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen)) 631 ret = 1; 632 OPENSSL_free(cn); 633 } 634 return (ret); 635 } 636 637 /* 638 * Verify that server certificate subjectAltName/CN matches 639 * hostname. First check, if there are alternative subject names. If yes, 640 * those have to match. Only if those don't exist it falls back to 641 * checking the subject's CN. 642 */ 643 static int 644 fetch_ssl_verify_hname(X509 *cert, const char *host) 645 { 646 struct addrinfo *ip; 647 STACK_OF(GENERAL_NAME) *altnames; 648 X509_NAME *subject; 649 int ret; 650 651 ret = 0; 652 ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host)); 653 altnames = X509_get_ext_d2i(cert, NID_subject_alt_name, 654 NULL, NULL); 655 656 if (altnames != NULL) { 657 ret = fetch_ssl_verify_altname(altnames, host, ip); 658 } else { 659 subject = X509_get_subject_name(cert); 660 if (subject != NULL) 661 ret = fetch_ssl_verify_cn(subject, host, ip); 662 } 663 664 if (ip != NULL) 665 freeaddrinfo(ip); 666 if (altnames != NULL) 667 GENERAL_NAMES_free(altnames); 668 return (ret); 669 } 670 671 /* 672 * Configure transport security layer based on environment. 673 */ 674 static void 675 fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose) 676 { 677 long ssl_ctx_options; 678 679 ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_TICKET; 680 if (getenv("SSL_ALLOW_SSL3") == NULL) 681 ssl_ctx_options |= SSL_OP_NO_SSLv3; 682 if (getenv("SSL_NO_TLS1") != NULL) 683 ssl_ctx_options |= SSL_OP_NO_TLSv1; 684 if (getenv("SSL_NO_TLS1_1") != NULL) 685 ssl_ctx_options |= SSL_OP_NO_TLSv1_1; 686 if (getenv("SSL_NO_TLS1_2") != NULL) 687 ssl_ctx_options |= SSL_OP_NO_TLSv1_2; 688 if (verbose) 689 fetch_info("SSL options: %lx", ssl_ctx_options); 690 SSL_CTX_set_options(ctx, ssl_ctx_options); 691 } 692 693 694 /* 695 * Configure peer verification based on environment. 696 */ 697 #define LOCAL_CERT_FILE "/usr/local/etc/ssl/cert.pem" 698 #define BASE_CERT_FILE "/etc/ssl/cert.pem" 699 static int 700 fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose) 701 { 702 X509_LOOKUP *crl_lookup; 703 X509_STORE *crl_store; 704 const char *ca_cert_file, *ca_cert_path, *crl_file; 705 706 if (getenv("SSL_NO_VERIFY_PEER") == NULL) { 707 ca_cert_file = getenv("SSL_CA_CERT_FILE"); 708 if (ca_cert_file == NULL && 709 access(LOCAL_CERT_FILE, R_OK) == 0) 710 ca_cert_file = LOCAL_CERT_FILE; 711 if (ca_cert_file == NULL && 712 access(BASE_CERT_FILE, R_OK) == 0) 713 ca_cert_file = BASE_CERT_FILE; 714 ca_cert_path = getenv("SSL_CA_CERT_PATH"); 715 if (verbose) { 716 fetch_info("Peer verification enabled"); 717 if (ca_cert_file != NULL) 718 fetch_info("Using CA cert file: %s", 719 ca_cert_file); 720 if (ca_cert_path != NULL) 721 fetch_info("Using CA cert path: %s", 722 ca_cert_path); 723 if (ca_cert_file == NULL && ca_cert_path == NULL) 724 fetch_info("Using OpenSSL default " 725 "CA cert file and path"); 726 } 727 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, 728 fetch_ssl_cb_verify_crt); 729 if (ca_cert_file != NULL || ca_cert_path != NULL) 730 SSL_CTX_load_verify_locations(ctx, ca_cert_file, 731 ca_cert_path); 732 else 733 SSL_CTX_set_default_verify_paths(ctx); 734 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) { 735 if (verbose) 736 fetch_info("Using CRL file: %s", crl_file); 737 crl_store = SSL_CTX_get_cert_store(ctx); 738 crl_lookup = X509_STORE_add_lookup(crl_store, 739 X509_LOOKUP_file()); 740 if (crl_lookup == NULL || 741 !X509_load_crl_file(crl_lookup, crl_file, 742 X509_FILETYPE_PEM)) { 743 fprintf(stderr, 744 "Could not load CRL file %s\n", 745 crl_file); 746 return (0); 747 } 748 X509_STORE_set_flags(crl_store, 749 X509_V_FLAG_CRL_CHECK | 750 X509_V_FLAG_CRL_CHECK_ALL); 751 } 752 } 753 return (1); 754 } 755 756 /* 757 * Configure client certificate based on environment. 758 */ 759 static int 760 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose) 761 { 762 const char *client_cert_file, *client_key_file; 763 764 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) { 765 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ? 766 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file; 767 if (verbose) { 768 fetch_info("Using client cert file: %s", 769 client_cert_file); 770 fetch_info("Using client key file: %s", 771 client_key_file); 772 } 773 if (SSL_CTX_use_certificate_chain_file(ctx, 774 client_cert_file) != 1) { 775 fprintf(stderr, 776 "Could not load client certificate %s\n", 777 client_cert_file); 778 return (0); 779 } 780 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file, 781 SSL_FILETYPE_PEM) != 1) { 782 fprintf(stderr, 783 "Could not load client key %s\n", 784 client_key_file); 785 return (0); 786 } 787 } 788 return (1); 789 } 790 791 /* 792 * Callback for SSL certificate verification, this is called on server 793 * cert verification. It takes no decision, but informs the user in case 794 * verification failed. 795 */ 796 int 797 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx) 798 { 799 X509 *crt; 800 X509_NAME *name; 801 char *str; 802 803 str = NULL; 804 if (!verified) { 805 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL && 806 (name = X509_get_subject_name(crt)) != NULL) 807 str = X509_NAME_oneline(name, 0, 0); 808 fprintf(stderr, "Certificate verification failed for %s\n", 809 str != NULL ? str : "no relevant certificate"); 810 OPENSSL_free(str); 811 } 812 return (verified); 813 } 814 815 #endif 816 817 /* 818 * Enable SSL on a connection. 819 */ 820 int 821 fetch_ssl(conn_t *conn, const struct url *URL, int verbose) 822 { 823 #ifdef WITH_SSL 824 int ret, ssl_err; 825 X509_NAME *name; 826 char *str; 827 828 /* Init the SSL library and context */ 829 if (!SSL_library_init()){ 830 fprintf(stderr, "SSL library init failed\n"); 831 return (-1); 832 } 833 834 SSL_load_error_strings(); 835 836 conn->ssl_meth = SSLv23_client_method(); 837 conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth); 838 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY); 839 840 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose); 841 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose)) 842 return (-1); 843 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose)) 844 return (-1); 845 846 conn->ssl = SSL_new(conn->ssl_ctx); 847 if (conn->ssl == NULL) { 848 fprintf(stderr, "SSL context creation failed\n"); 849 return (-1); 850 } 851 SSL_set_fd(conn->ssl, conn->sd); 852 853 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) 854 if (!SSL_set_tlsext_host_name(conn->ssl, 855 __DECONST(struct url *, URL)->host)) { 856 fprintf(stderr, 857 "TLS server name indication extension failed for host %s\n", 858 URL->host); 859 return (-1); 860 } 861 #endif 862 while ((ret = SSL_connect(conn->ssl)) == -1) { 863 ssl_err = SSL_get_error(conn->ssl, ret); 864 if (ssl_err != SSL_ERROR_WANT_READ && 865 ssl_err != SSL_ERROR_WANT_WRITE) { 866 ERR_print_errors_fp(stderr); 867 return (-1); 868 } 869 } 870 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl); 871 872 if (conn->ssl_cert == NULL) { 873 fprintf(stderr, "No server SSL certificate\n"); 874 return (-1); 875 } 876 877 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) { 878 if (verbose) 879 fetch_info("Verify hostname"); 880 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) { 881 fprintf(stderr, 882 "SSL certificate subject doesn't match host %s\n", 883 URL->host); 884 return (-1); 885 } 886 } 887 888 if (verbose) { 889 fetch_info("%s connection established using %s", 890 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl)); 891 name = X509_get_subject_name(conn->ssl_cert); 892 str = X509_NAME_oneline(name, 0, 0); 893 fetch_info("Certificate subject: %s", str); 894 OPENSSL_free(str); 895 name = X509_get_issuer_name(conn->ssl_cert); 896 str = X509_NAME_oneline(name, 0, 0); 897 fetch_info("Certificate issuer: %s", str); 898 OPENSSL_free(str); 899 } 900 901 return (0); 902 #else 903 (void)conn; 904 (void)verbose; 905 fprintf(stderr, "SSL support disabled\n"); 906 return (-1); 907 #endif 908 } 909 910 #define FETCH_READ_WAIT -2 911 #define FETCH_READ_ERROR -1 912 #define FETCH_READ_DONE 0 913 914 #ifdef WITH_SSL 915 static ssize_t 916 fetch_ssl_read(SSL *ssl, char *buf, size_t len) 917 { 918 ssize_t rlen; 919 int ssl_err; 920 921 rlen = SSL_read(ssl, buf, len); 922 if (rlen < 0) { 923 ssl_err = SSL_get_error(ssl, rlen); 924 if (ssl_err == SSL_ERROR_WANT_READ || 925 ssl_err == SSL_ERROR_WANT_WRITE) { 926 return (FETCH_READ_WAIT); 927 } else { 928 ERR_print_errors_fp(stderr); 929 return (FETCH_READ_ERROR); 930 } 931 } 932 return (rlen); 933 } 934 #endif 935 936 static ssize_t 937 fetch_socket_read(int sd, char *buf, size_t len) 938 { 939 ssize_t rlen; 940 941 rlen = read(sd, buf, len); 942 if (rlen < 0) { 943 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls)) 944 return (FETCH_READ_WAIT); 945 else 946 return (FETCH_READ_ERROR); 947 } 948 return (rlen); 949 } 950 951 /* 952 * Read a character from a connection w/ timeout 953 */ 954 ssize_t 955 fetch_read(conn_t *conn, char *buf, size_t len) 956 { 957 struct timeval now, timeout, delta; 958 struct pollfd pfd; 959 ssize_t rlen; 960 int deltams; 961 962 if (fetchTimeout > 0) { 963 gettimeofday(&timeout, NULL); 964 timeout.tv_sec += fetchTimeout; 965 } 966 967 deltams = INFTIM; 968 memset(&pfd, 0, sizeof pfd); 969 pfd.fd = conn->sd; 970 pfd.events = POLLIN | POLLERR; 971 972 for (;;) { 973 /* 974 * The socket is non-blocking. Instead of the canonical 975 * poll() -> read(), we do the following: 976 * 977 * 1) call read() or SSL_read(). 978 * 2) if we received some data, return it. 979 * 3) if an error occurred, return -1. 980 * 4) if read() or SSL_read() signaled EOF, return. 981 * 5) if we did not receive any data but we're not at EOF, 982 * call poll(). 983 * 984 * In the SSL case, this is necessary because if we 985 * receive a close notification, we have to call 986 * SSL_read() one additional time after we've read 987 * everything we received. 988 * 989 * In the non-SSL case, it may improve performance (very 990 * slightly) when reading small amounts of data. 991 */ 992 #ifdef WITH_SSL 993 if (conn->ssl != NULL) 994 rlen = fetch_ssl_read(conn->ssl, buf, len); 995 else 996 #endif 997 rlen = fetch_socket_read(conn->sd, buf, len); 998 if (rlen >= 0) { 999 break; 1000 } else if (rlen == FETCH_READ_ERROR) { 1001 fetch_syserr(); 1002 return (-1); 1003 } 1004 // assert(rlen == FETCH_READ_WAIT); 1005 if (fetchTimeout > 0) { 1006 gettimeofday(&now, NULL); 1007 if (!timercmp(&timeout, &now, >)) { 1008 errno = ETIMEDOUT; 1009 fetch_syserr(); 1010 return (-1); 1011 } 1012 timersub(&timeout, &now, &delta); 1013 deltams = delta.tv_sec * 1000 + 1014 delta.tv_usec / 1000;; 1015 } 1016 errno = 0; 1017 pfd.revents = 0; 1018 if (poll(&pfd, 1, deltams) < 0) { 1019 if (errno == EINTR && fetchRestartCalls) 1020 continue; 1021 fetch_syserr(); 1022 return (-1); 1023 } 1024 } 1025 return (rlen); 1026 } 1027 1028 1029 /* 1030 * Read a line of text from a connection w/ timeout 1031 */ 1032 #define MIN_BUF_SIZE 1024 1033 1034 int 1035 fetch_getln(conn_t *conn) 1036 { 1037 char *tmp; 1038 size_t tmpsize; 1039 ssize_t len; 1040 char c; 1041 1042 if (conn->buf == NULL) { 1043 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) { 1044 errno = ENOMEM; 1045 return (-1); 1046 } 1047 conn->bufsize = MIN_BUF_SIZE; 1048 } 1049 1050 conn->buf[0] = '\0'; 1051 conn->buflen = 0; 1052 1053 do { 1054 len = fetch_read(conn, &c, 1); 1055 if (len == -1) 1056 return (-1); 1057 if (len == 0) 1058 break; 1059 conn->buf[conn->buflen++] = c; 1060 if (conn->buflen == conn->bufsize) { 1061 tmp = conn->buf; 1062 tmpsize = conn->bufsize * 2 + 1; 1063 if ((tmp = realloc(tmp, tmpsize)) == NULL) { 1064 errno = ENOMEM; 1065 return (-1); 1066 } 1067 conn->buf = tmp; 1068 conn->bufsize = tmpsize; 1069 } 1070 } while (c != '\n'); 1071 1072 conn->buf[conn->buflen] = '\0'; 1073 DEBUG(fprintf(stderr, "<<< %s", conn->buf)); 1074 return (0); 1075 } 1076 1077 1078 /* 1079 * Write to a connection w/ timeout 1080 */ 1081 ssize_t 1082 fetch_write(conn_t *conn, const char *buf, size_t len) 1083 { 1084 struct iovec iov; 1085 1086 iov.iov_base = __DECONST(char *, buf); 1087 iov.iov_len = len; 1088 return fetch_writev(conn, &iov, 1); 1089 } 1090 1091 /* 1092 * Write a vector to a connection w/ timeout 1093 * Note: can modify the iovec. 1094 */ 1095 ssize_t 1096 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt) 1097 { 1098 struct timeval now, timeout, delta; 1099 struct pollfd pfd; 1100 ssize_t wlen, total; 1101 int deltams; 1102 1103 memset(&pfd, 0, sizeof pfd); 1104 if (fetchTimeout) { 1105 pfd.fd = conn->sd; 1106 pfd.events = POLLOUT | POLLERR; 1107 gettimeofday(&timeout, NULL); 1108 timeout.tv_sec += fetchTimeout; 1109 } 1110 1111 total = 0; 1112 while (iovcnt > 0) { 1113 while (fetchTimeout && pfd.revents == 0) { 1114 gettimeofday(&now, NULL); 1115 if (!timercmp(&timeout, &now, >)) { 1116 errno = ETIMEDOUT; 1117 fetch_syserr(); 1118 return (-1); 1119 } 1120 timersub(&timeout, &now, &delta); 1121 deltams = delta.tv_sec * 1000 + 1122 delta.tv_usec / 1000; 1123 errno = 0; 1124 pfd.revents = 0; 1125 if (poll(&pfd, 1, deltams) < 0) { 1126 /* POSIX compliance */ 1127 if (errno == EAGAIN) 1128 continue; 1129 if (errno == EINTR && fetchRestartCalls) 1130 continue; 1131 return (-1); 1132 } 1133 } 1134 errno = 0; 1135 #ifdef WITH_SSL 1136 if (conn->ssl != NULL) 1137 wlen = SSL_write(conn->ssl, 1138 iov->iov_base, iov->iov_len); 1139 else 1140 #endif 1141 wlen = writev(conn->sd, iov, iovcnt); 1142 if (wlen == 0) { 1143 /* we consider a short write a failure */ 1144 /* XXX perhaps we shouldn't in the SSL case */ 1145 errno = EPIPE; 1146 fetch_syserr(); 1147 return (-1); 1148 } 1149 if (wlen < 0) { 1150 if (errno == EINTR && fetchRestartCalls) 1151 continue; 1152 return (-1); 1153 } 1154 total += wlen; 1155 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) { 1156 wlen -= iov->iov_len; 1157 iov++; 1158 iovcnt--; 1159 } 1160 if (iovcnt > 0) { 1161 iov->iov_len -= wlen; 1162 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen; 1163 } 1164 } 1165 return (total); 1166 } 1167 1168 1169 /* 1170 * Write a line of text to a connection w/ timeout 1171 */ 1172 int 1173 fetch_putln(conn_t *conn, const char *str, size_t len) 1174 { 1175 struct iovec iov[2]; 1176 int ret; 1177 1178 DEBUG(fprintf(stderr, ">>> %s\n", str)); 1179 iov[0].iov_base = __DECONST(char *, str); 1180 iov[0].iov_len = len; 1181 iov[1].iov_base = __DECONST(char *, ENDL); 1182 iov[1].iov_len = sizeof(ENDL); 1183 if (len == 0) 1184 ret = fetch_writev(conn, &iov[1], 1); 1185 else 1186 ret = fetch_writev(conn, iov, 2); 1187 if (ret == -1) 1188 return (-1); 1189 return (0); 1190 } 1191 1192 1193 /* 1194 * Close connection 1195 */ 1196 int 1197 fetch_close(conn_t *conn) 1198 { 1199 int ret; 1200 1201 if (--conn->ref > 0) 1202 return (0); 1203 #ifdef WITH_SSL 1204 if (conn->ssl) { 1205 SSL_shutdown(conn->ssl); 1206 SSL_set_connect_state(conn->ssl); 1207 SSL_free(conn->ssl); 1208 conn->ssl = NULL; 1209 } 1210 if (conn->ssl_ctx) { 1211 SSL_CTX_free(conn->ssl_ctx); 1212 conn->ssl_ctx = NULL; 1213 } 1214 if (conn->ssl_cert) { 1215 X509_free(conn->ssl_cert); 1216 conn->ssl_cert = NULL; 1217 } 1218 #endif 1219 ret = close(conn->sd); 1220 free(conn->buf); 1221 free(conn); 1222 return (ret); 1223 } 1224 1225 1226 /*** Directory-related utility functions *************************************/ 1227 1228 int 1229 fetch_add_entry(struct url_ent **p, int *size, int *len, 1230 const char *name, struct url_stat *us) 1231 { 1232 struct url_ent *tmp; 1233 1234 if (*p == NULL) { 1235 *size = 0; 1236 *len = 0; 1237 } 1238 1239 if (*len >= *size - 1) { 1240 tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p)); 1241 if (tmp == NULL) { 1242 errno = ENOMEM; 1243 fetch_syserr(); 1244 return (-1); 1245 } 1246 *size = (*size * 2 + 1); 1247 *p = tmp; 1248 } 1249 1250 tmp = *p + *len; 1251 snprintf(tmp->name, PATH_MAX, "%s", name); 1252 memcpy(&tmp->stat, us, sizeof(*us)); 1253 1254 (*len)++; 1255 (++tmp)->name[0] = 0; 1256 1257 return (0); 1258 } 1259 1260 1261 /*** Authentication-related utility functions ********************************/ 1262 1263 static const char * 1264 fetch_read_word(FILE *f) 1265 { 1266 static char word[1024]; 1267 1268 if (fscanf(f, " %1023s ", word) != 1) 1269 return (NULL); 1270 return (word); 1271 } 1272 1273 /* 1274 * Get authentication data for a URL from .netrc 1275 */ 1276 int 1277 fetch_netrc_auth(struct url *url) 1278 { 1279 char fn[PATH_MAX]; 1280 const char *word; 1281 char *p; 1282 FILE *f; 1283 1284 if ((p = getenv("NETRC")) != NULL) { 1285 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) { 1286 fetch_info("$NETRC specifies a file name " 1287 "longer than PATH_MAX"); 1288 return (-1); 1289 } 1290 } else { 1291 if ((p = getenv("HOME")) != NULL) { 1292 struct passwd *pwd; 1293 1294 if ((pwd = getpwuid(getuid())) == NULL || 1295 (p = pwd->pw_dir) == NULL) 1296 return (-1); 1297 } 1298 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn)) 1299 return (-1); 1300 } 1301 1302 if ((f = fopen(fn, "r")) == NULL) 1303 return (-1); 1304 while ((word = fetch_read_word(f)) != NULL) { 1305 if (strcmp(word, "default") == 0) { 1306 DEBUG(fetch_info("Using default .netrc settings")); 1307 break; 1308 } 1309 if (strcmp(word, "machine") == 0 && 1310 (word = fetch_read_word(f)) != NULL && 1311 strcasecmp(word, url->host) == 0) { 1312 DEBUG(fetch_info("Using .netrc settings for %s", word)); 1313 break; 1314 } 1315 } 1316 if (word == NULL) 1317 goto ferr; 1318 while ((word = fetch_read_word(f)) != NULL) { 1319 if (strcmp(word, "login") == 0) { 1320 if ((word = fetch_read_word(f)) == NULL) 1321 goto ferr; 1322 if (snprintf(url->user, sizeof(url->user), 1323 "%s", word) > (int)sizeof(url->user)) { 1324 fetch_info("login name in .netrc is too long"); 1325 url->user[0] = '\0'; 1326 } 1327 } else if (strcmp(word, "password") == 0) { 1328 if ((word = fetch_read_word(f)) == NULL) 1329 goto ferr; 1330 if (snprintf(url->pwd, sizeof(url->pwd), 1331 "%s", word) > (int)sizeof(url->pwd)) { 1332 fetch_info("password in .netrc is too long"); 1333 url->pwd[0] = '\0'; 1334 } 1335 } else if (strcmp(word, "account") == 0) { 1336 if ((word = fetch_read_word(f)) == NULL) 1337 goto ferr; 1338 /* XXX not supported! */ 1339 } else { 1340 break; 1341 } 1342 } 1343 fclose(f); 1344 return (0); 1345 ferr: 1346 fclose(f); 1347 return (-1); 1348 } 1349 1350 /* 1351 * The no_proxy environment variable specifies a set of domains for 1352 * which the proxy should not be consulted; the contents is a comma-, 1353 * or space-separated list of domain names. A single asterisk will 1354 * override all proxy variables and no transactions will be proxied 1355 * (for compatibility with lynx and curl, see the discussion at 1356 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>). 1357 */ 1358 int 1359 fetch_no_proxy_match(const char *host) 1360 { 1361 const char *no_proxy, *p, *q; 1362 size_t h_len, d_len; 1363 1364 if ((no_proxy = getenv("NO_PROXY")) == NULL && 1365 (no_proxy = getenv("no_proxy")) == NULL) 1366 return (0); 1367 1368 /* asterisk matches any hostname */ 1369 if (strcmp(no_proxy, "*") == 0) 1370 return (1); 1371 1372 h_len = strlen(host); 1373 p = no_proxy; 1374 do { 1375 /* position p at the beginning of a domain suffix */ 1376 while (*p == ',' || isspace((unsigned char)*p)) 1377 p++; 1378 1379 /* position q at the first separator character */ 1380 for (q = p; *q; ++q) 1381 if (*q == ',' || isspace((unsigned char)*q)) 1382 break; 1383 1384 d_len = q - p; 1385 if (d_len > 0 && h_len >= d_len && 1386 strncasecmp(host + h_len - d_len, 1387 p, d_len) == 0) { 1388 /* domain name matches */ 1389 return (1); 1390 } 1391 1392 p = q + 1; 1393 } while (*q); 1394 1395 return (0); 1396 } 1397