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 return (0); 261 return (-1); 262 } 263 264 265 /* 266 * Establish a TCP connection to the specified port on the specified host. 267 */ 268 conn_t * 269 fetch_connect(const char *host, int port, int af, int verbose) 270 { 271 conn_t *conn; 272 char pbuf[10]; 273 const char *bindaddr; 274 struct addrinfo hints, *res, *res0; 275 int sd, err; 276 277 DEBUG(fprintf(stderr, "---> %s:%d\n", host, port)); 278 279 if (verbose) 280 fetch_info("looking up %s", host); 281 282 /* look up host name and set up socket address structure */ 283 snprintf(pbuf, sizeof(pbuf), "%d", port); 284 memset(&hints, 0, sizeof(hints)); 285 hints.ai_family = af; 286 hints.ai_socktype = SOCK_STREAM; 287 hints.ai_protocol = 0; 288 if ((err = getaddrinfo(host, pbuf, &hints, &res0)) != 0) { 289 netdb_seterr(err); 290 return (NULL); 291 } 292 bindaddr = getenv("FETCH_BIND_ADDRESS"); 293 294 if (verbose) 295 fetch_info("connecting to %s:%d", host, port); 296 297 /* try to connect */ 298 for (sd = -1, res = res0; res; sd = -1, res = res->ai_next) { 299 if ((sd = socket(res->ai_family, res->ai_socktype, 300 res->ai_protocol)) == -1) 301 continue; 302 if (bindaddr != NULL && *bindaddr != '\0' && 303 fetch_bind(sd, res->ai_family, bindaddr) != 0) { 304 fetch_info("failed to bind to '%s'", bindaddr); 305 close(sd); 306 continue; 307 } 308 if (connect(sd, res->ai_addr, res->ai_addrlen) == 0 && 309 fcntl(sd, F_SETFL, O_NONBLOCK) == 0) 310 break; 311 close(sd); 312 } 313 freeaddrinfo(res0); 314 if (sd == -1) { 315 fetch_syserr(); 316 return (NULL); 317 } 318 319 if ((conn = fetch_reopen(sd)) == NULL) { 320 fetch_syserr(); 321 close(sd); 322 } 323 return (conn); 324 } 325 326 #ifdef WITH_SSL 327 /* 328 * Convert characters A-Z to lowercase (intentionally avoid any locale 329 * specific conversions). 330 */ 331 static char 332 fetch_ssl_tolower(char in) 333 { 334 if (in >= 'A' && in <= 'Z') 335 return (in + 32); 336 else 337 return (in); 338 } 339 340 /* 341 * isalpha implementation that intentionally avoids any locale specific 342 * conversions. 343 */ 344 static int 345 fetch_ssl_isalpha(char in) 346 { 347 return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z')); 348 } 349 350 /* 351 * Check if passed hostnames a and b are equal. 352 */ 353 static int 354 fetch_ssl_hname_equal(const char *a, size_t alen, const char *b, 355 size_t blen) 356 { 357 size_t i; 358 359 if (alen != blen) 360 return (0); 361 for (i = 0; i < alen; ++i) { 362 if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i])) 363 return (0); 364 } 365 return (1); 366 } 367 368 /* 369 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9 370 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha- 371 * numeric characters. Double hyphens (like they're found in IDN a-labels 372 * 'xn--') are not allowed. Empty labels are invalid. 373 */ 374 static int 375 fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok) 376 { 377 size_t i; 378 379 if (!len || l[0] == '-' || l[len-1] == '-') 380 return (0); 381 for (i = 0; i < len; ++i) { 382 if (!isdigit(l[i]) && 383 !fetch_ssl_isalpha(l[i]) && 384 !(l[i] == '*' && wcok) && 385 !(l[i] == '-' && l[i - 1] != '-')) 386 return (0); 387 } 388 return (1); 389 } 390 391 /* 392 * Check if host name consists only of numbers. This might indicate an IP 393 * address, which is not a good idea for CN wildcard comparison. 394 */ 395 static int 396 fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len) 397 { 398 size_t i; 399 400 for (i = 0; i < len; ++i) { 401 if (!((hostname[i] >= '0' && hostname[i] <= '9') || 402 hostname[i] == '.')) 403 return (0); 404 } 405 return (1); 406 } 407 408 /* 409 * Check if the host name h passed matches the pattern passed in m which 410 * is usually part of subjectAltName or CN of a certificate presented to 411 * the client. This includes wildcard matching. The algorithm is based on 412 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280. 413 */ 414 static int 415 fetch_ssl_hname_match(const char *h, size_t hlen, const char *m, 416 size_t mlen) 417 { 418 int delta, hdotidx, mdot1idx, wcidx; 419 const char *hdot, *mdot1, *mdot2; 420 const char *wc; /* wildcard */ 421 422 if (!(h && *h && m && *m)) 423 return (0); 424 if ((wc = strnstr(m, "*", mlen)) == NULL) 425 return (fetch_ssl_hname_equal(h, hlen, m, mlen)); 426 wcidx = wc - m; 427 /* hostname should not be just dots and numbers */ 428 if (fetch_ssl_hname_is_only_numbers(h, hlen)) 429 return (0); 430 /* only one wildcard allowed in pattern */ 431 if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL) 432 return (0); 433 /* 434 * there must be at least two more domain labels and 435 * wildcard has to be in the leftmost label (RFC6125) 436 */ 437 mdot1 = strnstr(m, ".", mlen); 438 if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4) 439 return (0); 440 mdot1idx = mdot1 - m; 441 mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1); 442 if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2) 443 return (0); 444 /* hostname must contain a dot and not be the 1st char */ 445 hdot = strnstr(h, ".", hlen); 446 if (hdot == NULL || hdot == h) 447 return (0); 448 hdotidx = hdot - h; 449 /* 450 * host part of hostname must be at least as long as 451 * pattern it's supposed to match 452 */ 453 if (hdotidx < mdot1idx) 454 return (0); 455 /* 456 * don't allow wildcards in non-traditional domain names 457 * (IDN, A-label, U-label...) 458 */ 459 if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) || 460 !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1)) 461 return (0); 462 /* match domain part (part after first dot) */ 463 if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1, 464 mlen - mdot1idx)) 465 return (0); 466 /* match part left of wildcard */ 467 if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx)) 468 return (0); 469 /* match part right of wildcard */ 470 delta = mdot1idx - wcidx - 1; 471 if (!fetch_ssl_hname_equal(hdot - delta, delta, 472 mdot1 - delta, delta)) 473 return (0); 474 /* all tests succeded, it's a match */ 475 return (1); 476 } 477 478 /* 479 * Get numeric host address info - returns NULL if host was not an IP 480 * address. The caller is responsible for deallocation using 481 * freeaddrinfo(3). 482 */ 483 static struct addrinfo * 484 fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len) 485 { 486 struct addrinfo hints, *res; 487 char *host; 488 489 host = (char *)malloc(len + 1); 490 memcpy(host, hostname, len); 491 host[len] = '\0'; 492 memset(&hints, 0, sizeof(hints)); 493 hints.ai_family = PF_UNSPEC; 494 hints.ai_socktype = SOCK_STREAM; 495 hints.ai_protocol = 0; 496 hints.ai_flags = AI_NUMERICHOST; 497 /* port is not relevant for this purpose */ 498 getaddrinfo(host, "443", &hints, &res); 499 free(host); 500 return res; 501 } 502 503 /* 504 * Compare ip address in addrinfo with address passes. 505 */ 506 static int 507 fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost, 508 size_t rhostlen) 509 { 510 const void *left; 511 512 if (lhost->ai_family == AF_INET && rhostlen == 4) { 513 left = (void *)&((struct sockaddr_in*)(void *) 514 lhost->ai_addr)->sin_addr.s_addr; 515 #ifdef INET6 516 } else if (lhost->ai_family == AF_INET6 && rhostlen == 16) { 517 left = (void *)&((struct sockaddr_in6 *)(void *) 518 lhost->ai_addr)->sin6_addr; 519 #endif 520 } else 521 return (0); 522 return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0); 523 } 524 525 /* 526 * Compare ip address in addrinfo with host passed. If host is not an IP 527 * address, comparison will fail. 528 */ 529 static int 530 fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r, 531 size_t rlen) 532 { 533 struct addrinfo *raddr; 534 int ret; 535 char *rip; 536 537 ret = 0; 538 if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL) 539 return 0; /* not a numeric host */ 540 541 if (laddr->ai_family == raddr->ai_family) { 542 if (laddr->ai_family == AF_INET) { 543 rip = (char *)&((struct sockaddr_in *)(void *) 544 raddr->ai_addr)->sin_addr.s_addr; 545 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4); 546 #ifdef INET6 547 } else if (laddr->ai_family == AF_INET6) { 548 rip = (char *)&((struct sockaddr_in6 *)(void *) 549 raddr->ai_addr)->sin6_addr; 550 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16); 551 #endif 552 } 553 554 } 555 freeaddrinfo(raddr); 556 return (ret); 557 } 558 559 /* 560 * Verify server certificate by subjectAltName. 561 */ 562 static int 563 fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames, 564 const char *host, struct addrinfo *ip) 565 { 566 const GENERAL_NAME *name; 567 size_t nslen; 568 int i; 569 const char *ns; 570 571 for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) { 572 #if OPENSSL_VERSION_NUMBER < 0x10000000L 573 /* 574 * This is a workaround, since the following line causes 575 * alignment issues in clang: 576 * name = sk_GENERAL_NAME_value(altnames, i); 577 * OpenSSL explicitly warns not to use those macros 578 * directly, but there isn't much choice (and there 579 * shouldn't be any ill side effects) 580 */ 581 name = (GENERAL_NAME *)SKM_sk_value(void, altnames, i); 582 #else 583 name = sk_GENERAL_NAME_value(altnames, i); 584 #endif 585 ns = (const char *)ASN1_STRING_data(name->d.ia5); 586 nslen = (size_t)ASN1_STRING_length(name->d.ia5); 587 588 if (name->type == GEN_DNS && ip == NULL && 589 fetch_ssl_hname_match(host, strlen(host), ns, nslen)) 590 return (1); 591 else if (name->type == GEN_IPADD && ip != NULL && 592 fetch_ssl_ipaddr_match_bin(ip, ns, nslen)) 593 return (1); 594 } 595 return (0); 596 } 597 598 /* 599 * Verify server certificate by CN. 600 */ 601 static int 602 fetch_ssl_verify_cn(X509_NAME *subject, const char *host, 603 struct addrinfo *ip) 604 { 605 ASN1_STRING *namedata; 606 X509_NAME_ENTRY *nameentry; 607 int cnlen, lastpos, loc, ret; 608 unsigned char *cn; 609 610 ret = 0; 611 lastpos = -1; 612 loc = -1; 613 cn = NULL; 614 /* get most specific CN (last entry in list) and compare */ 615 while ((lastpos = X509_NAME_get_index_by_NID(subject, 616 NID_commonName, lastpos)) != -1) 617 loc = lastpos; 618 619 if (loc > -1) { 620 nameentry = X509_NAME_get_entry(subject, loc); 621 namedata = X509_NAME_ENTRY_get_data(nameentry); 622 cnlen = ASN1_STRING_to_UTF8(&cn, namedata); 623 if (ip == NULL && 624 fetch_ssl_hname_match(host, strlen(host), cn, cnlen)) 625 ret = 1; 626 else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen)) 627 ret = 1; 628 OPENSSL_free(cn); 629 } 630 return (ret); 631 } 632 633 /* 634 * Verify that server certificate subjectAltName/CN matches 635 * hostname. First check, if there are alternative subject names. If yes, 636 * those have to match. Only if those don't exist it falls back to 637 * checking the subject's CN. 638 */ 639 static int 640 fetch_ssl_verify_hname(X509 *cert, const char *host) 641 { 642 struct addrinfo *ip; 643 STACK_OF(GENERAL_NAME) *altnames; 644 X509_NAME *subject; 645 int ret; 646 647 ret = 0; 648 ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host)); 649 altnames = X509_get_ext_d2i(cert, NID_subject_alt_name, 650 NULL, NULL); 651 652 if (altnames != NULL) { 653 ret = fetch_ssl_verify_altname(altnames, host, ip); 654 } else { 655 subject = X509_get_subject_name(cert); 656 if (subject != NULL) 657 ret = fetch_ssl_verify_cn(subject, host, ip); 658 } 659 660 if (ip != NULL) 661 freeaddrinfo(ip); 662 if (altnames != NULL) 663 GENERAL_NAMES_free(altnames); 664 return (ret); 665 } 666 667 /* 668 * Configure transport security layer based on environment. 669 */ 670 static void 671 fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose) 672 { 673 long ssl_ctx_options; 674 675 ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_TICKET; 676 if (getenv("SSL_ALLOW_SSL2") == NULL) 677 ssl_ctx_options |= SSL_OP_NO_SSLv2; 678 if (getenv("SSL_ALLOW_SSL3") == NULL) 679 ssl_ctx_options |= SSL_OP_NO_SSLv3; 680 if (getenv("SSL_NO_TLS1") != NULL) 681 ssl_ctx_options |= SSL_OP_NO_TLSv1; 682 if (getenv("SSL_NO_TLS1_1") != NULL) 683 ssl_ctx_options |= SSL_OP_NO_TLSv1_1; 684 if (getenv("SSL_NO_TLS1_2") != NULL) 685 ssl_ctx_options |= SSL_OP_NO_TLSv1_2; 686 if (verbose) 687 fetch_info("SSL options: %lx", ssl_ctx_options); 688 SSL_CTX_set_options(ctx, ssl_ctx_options); 689 } 690 691 692 /* 693 * Configure peer verification based on environment. 694 */ 695 #define LOCAL_CERT_FILE "/usr/local/etc/ssl/cert.pem" 696 #define BASE_CERT_FILE "/etc/ssl/cert.pem" 697 static int 698 fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose) 699 { 700 X509_LOOKUP *crl_lookup; 701 X509_STORE *crl_store; 702 const char *ca_cert_file, *ca_cert_path, *crl_file; 703 704 if (getenv("SSL_NO_VERIFY_PEER") == NULL) { 705 ca_cert_file = getenv("SSL_CA_CERT_FILE"); 706 if (ca_cert_file == NULL && 707 access(LOCAL_CERT_FILE, R_OK) == 0) 708 ca_cert_file = LOCAL_CERT_FILE; 709 if (ca_cert_file == NULL) 710 ca_cert_file = BASE_CERT_FILE; 711 ca_cert_path = getenv("SSL_CA_CERT_PATH"); 712 if (verbose) { 713 fetch_info("Peer verification enabled"); 714 if (ca_cert_file != NULL) 715 fetch_info("Using CA cert file: %s", 716 ca_cert_file); 717 if (ca_cert_path != NULL) 718 fetch_info("Using CA cert path: %s", 719 ca_cert_path); 720 } 721 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER, 722 fetch_ssl_cb_verify_crt); 723 SSL_CTX_load_verify_locations(ctx, ca_cert_file, 724 ca_cert_path); 725 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) { 726 if (verbose) 727 fetch_info("Using CRL file: %s", crl_file); 728 crl_store = SSL_CTX_get_cert_store(ctx); 729 crl_lookup = X509_STORE_add_lookup(crl_store, 730 X509_LOOKUP_file()); 731 if (crl_lookup == NULL || 732 !X509_load_crl_file(crl_lookup, crl_file, 733 X509_FILETYPE_PEM)) { 734 fprintf(stderr, 735 "Could not load CRL file %s\n", 736 crl_file); 737 return (0); 738 } 739 X509_STORE_set_flags(crl_store, 740 X509_V_FLAG_CRL_CHECK | 741 X509_V_FLAG_CRL_CHECK_ALL); 742 } 743 } 744 return (1); 745 } 746 747 /* 748 * Configure client certificate based on environment. 749 */ 750 static int 751 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose) 752 { 753 const char *client_cert_file, *client_key_file; 754 755 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) { 756 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ? 757 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file; 758 if (verbose) { 759 fetch_info("Using client cert file: %s", 760 client_cert_file); 761 fetch_info("Using client key file: %s", 762 client_key_file); 763 } 764 if (SSL_CTX_use_certificate_chain_file(ctx, 765 client_cert_file) != 1) { 766 fprintf(stderr, 767 "Could not load client certificate %s\n", 768 client_cert_file); 769 return (0); 770 } 771 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file, 772 SSL_FILETYPE_PEM) != 1) { 773 fprintf(stderr, 774 "Could not load client key %s\n", 775 client_key_file); 776 return (0); 777 } 778 } 779 return (1); 780 } 781 782 /* 783 * Callback for SSL certificate verification, this is called on server 784 * cert verification. It takes no decision, but informs the user in case 785 * verification failed. 786 */ 787 int 788 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx) 789 { 790 X509 *crt; 791 X509_NAME *name; 792 char *str; 793 794 str = NULL; 795 if (!verified) { 796 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL && 797 (name = X509_get_subject_name(crt)) != NULL) 798 str = X509_NAME_oneline(name, 0, 0); 799 fprintf(stderr, "Certificate verification failed for %s\n", 800 str != NULL ? str : "no relevant certificate"); 801 OPENSSL_free(str); 802 } 803 return (verified); 804 } 805 806 #endif 807 808 /* 809 * Enable SSL on a connection. 810 */ 811 int 812 fetch_ssl(conn_t *conn, const struct url *URL, int verbose) 813 { 814 #ifdef WITH_SSL 815 int ret, ssl_err; 816 X509_NAME *name; 817 char *str; 818 819 /* Init the SSL library and context */ 820 if (!SSL_library_init()){ 821 fprintf(stderr, "SSL library init failed\n"); 822 return (-1); 823 } 824 825 SSL_load_error_strings(); 826 827 conn->ssl_meth = SSLv23_client_method(); 828 conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth); 829 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY); 830 831 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose); 832 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose)) 833 return (-1); 834 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose)) 835 return (-1); 836 837 conn->ssl = SSL_new(conn->ssl_ctx); 838 if (conn->ssl == NULL) { 839 fprintf(stderr, "SSL context creation failed\n"); 840 return (-1); 841 } 842 SSL_set_fd(conn->ssl, conn->sd); 843 844 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT) 845 if (!SSL_set_tlsext_host_name(conn->ssl, 846 __DECONST(struct url *, URL)->host)) { 847 fprintf(stderr, 848 "TLS server name indication extension failed for host %s\n", 849 URL->host); 850 return (-1); 851 } 852 #endif 853 while ((ret = SSL_connect(conn->ssl)) == -1) { 854 ssl_err = SSL_get_error(conn->ssl, ret); 855 if (ssl_err != SSL_ERROR_WANT_READ && 856 ssl_err != SSL_ERROR_WANT_WRITE) { 857 ERR_print_errors_fp(stderr); 858 return (-1); 859 } 860 } 861 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl); 862 863 if (conn->ssl_cert == NULL) { 864 fprintf(stderr, "No server SSL certificate\n"); 865 return (-1); 866 } 867 868 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) { 869 if (verbose) 870 fetch_info("Verify hostname"); 871 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) { 872 fprintf(stderr, 873 "SSL certificate subject doesn't match host %s\n", 874 URL->host); 875 return (-1); 876 } 877 } 878 879 if (verbose) { 880 fetch_info("%s connection established using %s", 881 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl)); 882 name = X509_get_subject_name(conn->ssl_cert); 883 str = X509_NAME_oneline(name, 0, 0); 884 fetch_info("Certificate subject: %s", str); 885 OPENSSL_free(str); 886 name = X509_get_issuer_name(conn->ssl_cert); 887 str = X509_NAME_oneline(name, 0, 0); 888 fetch_info("Certificate issuer: %s", str); 889 OPENSSL_free(str); 890 } 891 892 return (0); 893 #else 894 (void)conn; 895 (void)verbose; 896 fprintf(stderr, "SSL support disabled\n"); 897 return (-1); 898 #endif 899 } 900 901 #define FETCH_READ_WAIT -2 902 #define FETCH_READ_ERROR -1 903 #define FETCH_READ_DONE 0 904 905 #ifdef WITH_SSL 906 static ssize_t 907 fetch_ssl_read(SSL *ssl, char *buf, size_t len) 908 { 909 ssize_t rlen; 910 int ssl_err; 911 912 rlen = SSL_read(ssl, buf, len); 913 if (rlen < 0) { 914 ssl_err = SSL_get_error(ssl, rlen); 915 if (ssl_err == SSL_ERROR_WANT_READ || 916 ssl_err == SSL_ERROR_WANT_WRITE) { 917 return (FETCH_READ_WAIT); 918 } else { 919 ERR_print_errors_fp(stderr); 920 return (FETCH_READ_ERROR); 921 } 922 } 923 return (rlen); 924 } 925 #endif 926 927 static ssize_t 928 fetch_socket_read(int sd, char *buf, size_t len) 929 { 930 ssize_t rlen; 931 932 rlen = read(sd, buf, len); 933 if (rlen < 0) { 934 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls)) 935 return (FETCH_READ_WAIT); 936 else 937 return (FETCH_READ_ERROR); 938 } 939 return (rlen); 940 } 941 942 /* 943 * Read a character from a connection w/ timeout 944 */ 945 ssize_t 946 fetch_read(conn_t *conn, char *buf, size_t len) 947 { 948 struct timeval now, timeout, delta; 949 struct pollfd pfd; 950 ssize_t rlen; 951 int deltams; 952 953 if (fetchTimeout > 0) { 954 gettimeofday(&timeout, NULL); 955 timeout.tv_sec += fetchTimeout; 956 } 957 958 deltams = INFTIM; 959 memset(&pfd, 0, sizeof pfd); 960 pfd.fd = conn->sd; 961 pfd.events = POLLIN | POLLERR; 962 963 for (;;) { 964 /* 965 * The socket is non-blocking. Instead of the canonical 966 * poll() -> read(), we do the following: 967 * 968 * 1) call read() or SSL_read(). 969 * 2) if we received some data, return it. 970 * 3) if an error occurred, return -1. 971 * 4) if read() or SSL_read() signaled EOF, return. 972 * 5) if we did not receive any data but we're not at EOF, 973 * call poll(). 974 * 975 * In the SSL case, this is necessary because if we 976 * receive a close notification, we have to call 977 * SSL_read() one additional time after we've read 978 * everything we received. 979 * 980 * In the non-SSL case, it may improve performance (very 981 * slightly) when reading small amounts of data. 982 */ 983 #ifdef WITH_SSL 984 if (conn->ssl != NULL) 985 rlen = fetch_ssl_read(conn->ssl, buf, len); 986 else 987 #endif 988 rlen = fetch_socket_read(conn->sd, buf, len); 989 if (rlen >= 0) { 990 break; 991 } else if (rlen == FETCH_READ_ERROR) { 992 fetch_syserr(); 993 return (-1); 994 } 995 // assert(rlen == FETCH_READ_WAIT); 996 if (fetchTimeout > 0) { 997 gettimeofday(&now, NULL); 998 if (!timercmp(&timeout, &now, >)) { 999 errno = ETIMEDOUT; 1000 fetch_syserr(); 1001 return (-1); 1002 } 1003 timersub(&timeout, &now, &delta); 1004 deltams = delta.tv_sec * 1000 + 1005 delta.tv_usec / 1000;; 1006 } 1007 errno = 0; 1008 pfd.revents = 0; 1009 if (poll(&pfd, 1, deltams) < 0) { 1010 if (errno == EINTR && fetchRestartCalls) 1011 continue; 1012 fetch_syserr(); 1013 return (-1); 1014 } 1015 } 1016 return (rlen); 1017 } 1018 1019 1020 /* 1021 * Read a line of text from a connection w/ timeout 1022 */ 1023 #define MIN_BUF_SIZE 1024 1024 1025 int 1026 fetch_getln(conn_t *conn) 1027 { 1028 char *tmp; 1029 size_t tmpsize; 1030 ssize_t len; 1031 char c; 1032 1033 if (conn->buf == NULL) { 1034 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) { 1035 errno = ENOMEM; 1036 return (-1); 1037 } 1038 conn->bufsize = MIN_BUF_SIZE; 1039 } 1040 1041 conn->buf[0] = '\0'; 1042 conn->buflen = 0; 1043 1044 do { 1045 len = fetch_read(conn, &c, 1); 1046 if (len == -1) 1047 return (-1); 1048 if (len == 0) 1049 break; 1050 conn->buf[conn->buflen++] = c; 1051 if (conn->buflen == conn->bufsize) { 1052 tmp = conn->buf; 1053 tmpsize = conn->bufsize * 2 + 1; 1054 if ((tmp = realloc(tmp, tmpsize)) == NULL) { 1055 errno = ENOMEM; 1056 return (-1); 1057 } 1058 conn->buf = tmp; 1059 conn->bufsize = tmpsize; 1060 } 1061 } while (c != '\n'); 1062 1063 conn->buf[conn->buflen] = '\0'; 1064 DEBUG(fprintf(stderr, "<<< %s", conn->buf)); 1065 return (0); 1066 } 1067 1068 1069 /* 1070 * Write to a connection w/ timeout 1071 */ 1072 ssize_t 1073 fetch_write(conn_t *conn, const char *buf, size_t len) 1074 { 1075 struct iovec iov; 1076 1077 iov.iov_base = __DECONST(char *, buf); 1078 iov.iov_len = len; 1079 return fetch_writev(conn, &iov, 1); 1080 } 1081 1082 /* 1083 * Write a vector to a connection w/ timeout 1084 * Note: can modify the iovec. 1085 */ 1086 ssize_t 1087 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt) 1088 { 1089 struct timeval now, timeout, delta; 1090 struct pollfd pfd; 1091 ssize_t wlen, total; 1092 int deltams; 1093 1094 memset(&pfd, 0, sizeof pfd); 1095 if (fetchTimeout) { 1096 pfd.fd = conn->sd; 1097 pfd.events = POLLOUT | POLLERR; 1098 gettimeofday(&timeout, NULL); 1099 timeout.tv_sec += fetchTimeout; 1100 } 1101 1102 total = 0; 1103 while (iovcnt > 0) { 1104 while (fetchTimeout && pfd.revents == 0) { 1105 gettimeofday(&now, NULL); 1106 if (!timercmp(&timeout, &now, >)) { 1107 errno = ETIMEDOUT; 1108 fetch_syserr(); 1109 return (-1); 1110 } 1111 timersub(&timeout, &now, &delta); 1112 deltams = delta.tv_sec * 1000 + 1113 delta.tv_usec / 1000; 1114 errno = 0; 1115 pfd.revents = 0; 1116 if (poll(&pfd, 1, deltams) < 0) { 1117 /* POSIX compliance */ 1118 if (errno == EAGAIN) 1119 continue; 1120 if (errno == EINTR && fetchRestartCalls) 1121 continue; 1122 return (-1); 1123 } 1124 } 1125 errno = 0; 1126 #ifdef WITH_SSL 1127 if (conn->ssl != NULL) 1128 wlen = SSL_write(conn->ssl, 1129 iov->iov_base, iov->iov_len); 1130 else 1131 #endif 1132 wlen = writev(conn->sd, iov, iovcnt); 1133 if (wlen == 0) { 1134 /* we consider a short write a failure */ 1135 /* XXX perhaps we shouldn't in the SSL case */ 1136 errno = EPIPE; 1137 fetch_syserr(); 1138 return (-1); 1139 } 1140 if (wlen < 0) { 1141 if (errno == EINTR && fetchRestartCalls) 1142 continue; 1143 return (-1); 1144 } 1145 total += wlen; 1146 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) { 1147 wlen -= iov->iov_len; 1148 iov++; 1149 iovcnt--; 1150 } 1151 if (iovcnt > 0) { 1152 iov->iov_len -= wlen; 1153 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen; 1154 } 1155 } 1156 return (total); 1157 } 1158 1159 1160 /* 1161 * Write a line of text to a connection w/ timeout 1162 */ 1163 int 1164 fetch_putln(conn_t *conn, const char *str, size_t len) 1165 { 1166 struct iovec iov[2]; 1167 int ret; 1168 1169 DEBUG(fprintf(stderr, ">>> %s\n", str)); 1170 iov[0].iov_base = __DECONST(char *, str); 1171 iov[0].iov_len = len; 1172 iov[1].iov_base = __DECONST(char *, ENDL); 1173 iov[1].iov_len = sizeof(ENDL); 1174 if (len == 0) 1175 ret = fetch_writev(conn, &iov[1], 1); 1176 else 1177 ret = fetch_writev(conn, iov, 2); 1178 if (ret == -1) 1179 return (-1); 1180 return (0); 1181 } 1182 1183 1184 /* 1185 * Close connection 1186 */ 1187 int 1188 fetch_close(conn_t *conn) 1189 { 1190 int ret; 1191 1192 if (--conn->ref > 0) 1193 return (0); 1194 #ifdef WITH_SSL 1195 if (conn->ssl) { 1196 SSL_shutdown(conn->ssl); 1197 SSL_set_connect_state(conn->ssl); 1198 SSL_free(conn->ssl); 1199 conn->ssl = NULL; 1200 } 1201 if (conn->ssl_ctx) { 1202 SSL_CTX_free(conn->ssl_ctx); 1203 conn->ssl_ctx = NULL; 1204 } 1205 if (conn->ssl_cert) { 1206 X509_free(conn->ssl_cert); 1207 conn->ssl_cert = NULL; 1208 } 1209 #endif 1210 ret = close(conn->sd); 1211 free(conn->buf); 1212 free(conn); 1213 return (ret); 1214 } 1215 1216 1217 /*** Directory-related utility functions *************************************/ 1218 1219 int 1220 fetch_add_entry(struct url_ent **p, int *size, int *len, 1221 const char *name, struct url_stat *us) 1222 { 1223 struct url_ent *tmp; 1224 1225 if (*p == NULL) { 1226 *size = 0; 1227 *len = 0; 1228 } 1229 1230 if (*len >= *size - 1) { 1231 tmp = realloc(*p, (*size * 2 + 1) * sizeof(**p)); 1232 if (tmp == NULL) { 1233 errno = ENOMEM; 1234 fetch_syserr(); 1235 return (-1); 1236 } 1237 *size = (*size * 2 + 1); 1238 *p = tmp; 1239 } 1240 1241 tmp = *p + *len; 1242 snprintf(tmp->name, PATH_MAX, "%s", name); 1243 memcpy(&tmp->stat, us, sizeof(*us)); 1244 1245 (*len)++; 1246 (++tmp)->name[0] = 0; 1247 1248 return (0); 1249 } 1250 1251 1252 /*** Authentication-related utility functions ********************************/ 1253 1254 static const char * 1255 fetch_read_word(FILE *f) 1256 { 1257 static char word[1024]; 1258 1259 if (fscanf(f, " %1023s ", word) != 1) 1260 return (NULL); 1261 return (word); 1262 } 1263 1264 /* 1265 * Get authentication data for a URL from .netrc 1266 */ 1267 int 1268 fetch_netrc_auth(struct url *url) 1269 { 1270 char fn[PATH_MAX]; 1271 const char *word; 1272 char *p; 1273 FILE *f; 1274 1275 if ((p = getenv("NETRC")) != NULL) { 1276 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) { 1277 fetch_info("$NETRC specifies a file name " 1278 "longer than PATH_MAX"); 1279 return (-1); 1280 } 1281 } else { 1282 if ((p = getenv("HOME")) != NULL) { 1283 struct passwd *pwd; 1284 1285 if ((pwd = getpwuid(getuid())) == NULL || 1286 (p = pwd->pw_dir) == NULL) 1287 return (-1); 1288 } 1289 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn)) 1290 return (-1); 1291 } 1292 1293 if ((f = fopen(fn, "r")) == NULL) 1294 return (-1); 1295 while ((word = fetch_read_word(f)) != NULL) { 1296 if (strcmp(word, "default") == 0) { 1297 DEBUG(fetch_info("Using default .netrc settings")); 1298 break; 1299 } 1300 if (strcmp(word, "machine") == 0 && 1301 (word = fetch_read_word(f)) != NULL && 1302 strcasecmp(word, url->host) == 0) { 1303 DEBUG(fetch_info("Using .netrc settings for %s", word)); 1304 break; 1305 } 1306 } 1307 if (word == NULL) 1308 goto ferr; 1309 while ((word = fetch_read_word(f)) != NULL) { 1310 if (strcmp(word, "login") == 0) { 1311 if ((word = fetch_read_word(f)) == NULL) 1312 goto ferr; 1313 if (snprintf(url->user, sizeof(url->user), 1314 "%s", word) > (int)sizeof(url->user)) { 1315 fetch_info("login name in .netrc is too long"); 1316 url->user[0] = '\0'; 1317 } 1318 } else if (strcmp(word, "password") == 0) { 1319 if ((word = fetch_read_word(f)) == NULL) 1320 goto ferr; 1321 if (snprintf(url->pwd, sizeof(url->pwd), 1322 "%s", word) > (int)sizeof(url->pwd)) { 1323 fetch_info("password in .netrc is too long"); 1324 url->pwd[0] = '\0'; 1325 } 1326 } else if (strcmp(word, "account") == 0) { 1327 if ((word = fetch_read_word(f)) == NULL) 1328 goto ferr; 1329 /* XXX not supported! */ 1330 } else { 1331 break; 1332 } 1333 } 1334 fclose(f); 1335 return (0); 1336 ferr: 1337 fclose(f); 1338 return (-1); 1339 } 1340 1341 /* 1342 * The no_proxy environment variable specifies a set of domains for 1343 * which the proxy should not be consulted; the contents is a comma-, 1344 * or space-separated list of domain names. A single asterisk will 1345 * override all proxy variables and no transactions will be proxied 1346 * (for compatability with lynx and curl, see the discussion at 1347 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>). 1348 */ 1349 int 1350 fetch_no_proxy_match(const char *host) 1351 { 1352 const char *no_proxy, *p, *q; 1353 size_t h_len, d_len; 1354 1355 if ((no_proxy = getenv("NO_PROXY")) == NULL && 1356 (no_proxy = getenv("no_proxy")) == NULL) 1357 return (0); 1358 1359 /* asterisk matches any hostname */ 1360 if (strcmp(no_proxy, "*") == 0) 1361 return (1); 1362 1363 h_len = strlen(host); 1364 p = no_proxy; 1365 do { 1366 /* position p at the beginning of a domain suffix */ 1367 while (*p == ',' || isspace((unsigned char)*p)) 1368 p++; 1369 1370 /* position q at the first separator character */ 1371 for (q = p; *q; ++q) 1372 if (*q == ',' || isspace((unsigned char)*q)) 1373 break; 1374 1375 d_len = q - p; 1376 if (d_len > 0 && h_len >= d_len && 1377 strncasecmp(host + h_len - d_len, 1378 p, d_len) == 0) { 1379 /* domain name matches */ 1380 return (1); 1381 } 1382 1383 p = q + 1; 1384 } while (*q); 1385 1386 return (0); 1387 } 1388