2 * SPDX-License-Identifier: BSD-3-Clause
4 * Copyright (c) 1998-2016 Dag-Erling Smørgrav
5 * Copyright (c) 2013 Michael Gmelin <freebsd@grem.de>
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
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
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.
32 #include <sys/cdefs.h>
33 __FBSDID("$FreeBSD$");
35 #include <sys/param.h>
36 #include <sys/socket.h>
40 #include <netinet/in.h>
56 #include <openssl/x509v3.h>
63 /*** Local data **************************************************************/
66 * Error messages for resolver errors
68 static struct fetcherr netdb_errlist[] = {
70 { EAI_NODATA, FETCH_RESOLV, "Host not found" },
72 { EAI_AGAIN, FETCH_TEMP, "Transient resolver failure" },
73 { EAI_FAIL, FETCH_RESOLV, "Non-recoverable resolver failure" },
74 { EAI_NONAME, FETCH_RESOLV, "No address record" },
75 { -1, FETCH_UNKNOWN, "Unknown resolver error" }
79 * SOCKS5 error enumerations
84 SOCKS5_ERR_READ_METHOD,
87 SOCKS5_ERR_NOTIMPLEMENTED,
88 SOCKS5_ERR_HOSTNAME_SIZE,
91 SOCKS5_ERR_NON_VER5_RESP,
93 SOCKS5_ERR_NOT_ALLOWED,
94 SOCKS5_ERR_NET_UNREACHABLE,
95 SOCKS5_ERR_HOST_UNREACHABLE,
96 SOCKS5_ERR_CONN_REFUSED,
97 SOCKS5_ERR_TTL_EXPIRED,
98 SOCKS5_ERR_COM_UNSUPPORTED,
99 SOCKS5_ERR_ADDR_UNSUPPORTED,
100 SOCKS5_ERR_UNSPECIFIED,
101 /* Configuration errors */
103 SOCKS5_ERR_BAD_PROXY_FORMAT,
108 * Error messages for SOCKS5 errors
110 static struct fetcherr socks5_errlist[] = {
111 /* SOCKS5 protocol errors */
112 { SOCKS5_ERR_SELECTION, FETCH_ABORT, "SOCKS5: Failed to send selection method" },
113 { SOCKS5_ERR_READ_METHOD, FETCH_ABORT, "SOCKS5: Failed to read method" },
114 { SOCKS5_ERR_VER5_ONLY, FETCH_PROTO, "SOCKS5: Only version 5 is implemented" },
115 { SOCKS5_ERR_NOMETHODS, FETCH_PROTO, "SOCKS5: No acceptable methods" },
116 { SOCKS5_ERR_NOTIMPLEMENTED, FETCH_PROTO, "SOCKS5: Method currently not implemented" },
117 { SOCKS5_ERR_HOSTNAME_SIZE, FETCH_PROTO, "SOCKS5: Hostname size is above 256 bytes" },
118 { SOCKS5_ERR_REQUEST, FETCH_PROTO, "SOCKS5: Failed to request" },
119 { SOCKS5_ERR_REPLY, FETCH_PROTO, "SOCKS5: Failed to receive reply" },
120 { SOCKS5_ERR_NON_VER5_RESP, FETCH_PROTO, "SOCKS5: Server responded with a non-version 5 response" },
121 { SOCKS5_ERR_GENERAL, FETCH_ABORT, "SOCKS5: General server failure" },
122 { SOCKS5_ERR_NOT_ALLOWED, FETCH_AUTH, "SOCKS5: Connection not allowed by ruleset" },
123 { SOCKS5_ERR_NET_UNREACHABLE, FETCH_NETWORK, "SOCKS5: Network unreachable" },
124 { SOCKS5_ERR_HOST_UNREACHABLE, FETCH_ABORT, "SOCKS5: Host unreachable" },
125 { SOCKS5_ERR_CONN_REFUSED, FETCH_ABORT, "SOCKS5: Connection refused" },
126 { SOCKS5_ERR_TTL_EXPIRED, FETCH_TIMEOUT, "SOCKS5: TTL expired" },
127 { SOCKS5_ERR_COM_UNSUPPORTED, FETCH_PROTO, "SOCKS5: Command not supported" },
128 { SOCKS5_ERR_ADDR_UNSUPPORTED, FETCH_ABORT, "SOCKS5: Address type not supported" },
129 { SOCKS5_ERR_UNSPECIFIED, FETCH_UNKNOWN, "SOCKS5: Unspecified error" },
130 /* Configuration error */
131 { SOCKS5_ERR_BAD_HOST, FETCH_ABORT, "SOCKS5: Bad proxy host" },
132 { SOCKS5_ERR_BAD_PROXY_FORMAT, FETCH_ABORT, "SOCKS5: Bad proxy format" },
133 { SOCKS5_ERR_BAD_PORT, FETCH_ABORT, "SOCKS5: Bad port" }
137 static const char ENDL[2] = "\r\n";
140 /*** Error-reporting functions ***********************************************/
143 * Map error code to string
145 static struct fetcherr *
146 fetch_finderr(struct fetcherr *p, int e)
148 while (p->num != -1 && p->num != e)
157 fetch_seterr(struct fetcherr *p, int e)
159 p = fetch_finderr(p, e);
160 fetchLastErrCode = p->cat;
161 snprintf(fetchLastErrString, MAXERRSTRING, "%s", p->string);
165 * Set error code according to errno
172 fetchLastErrCode = FETCH_OK;
179 fetchLastErrCode = FETCH_AUTH;
182 case EISDIR: /* XXX */
183 fetchLastErrCode = FETCH_UNAVAIL;
186 fetchLastErrCode = FETCH_MEMORY;
190 fetchLastErrCode = FETCH_TEMP;
193 fetchLastErrCode = FETCH_EXISTS;
196 fetchLastErrCode = FETCH_FULL;
204 fetchLastErrCode = FETCH_NETWORK;
208 fetchLastErrCode = FETCH_ABORT;
211 fetchLastErrCode = FETCH_TIMEOUT;
215 fetchLastErrCode = FETCH_DOWN;
218 fetchLastErrCode = FETCH_UNKNOWN;
220 snprintf(fetchLastErrString, MAXERRSTRING, "%s", strerror(errno));
225 * Emit status message
228 fetch_info(const char *fmt, ...)
233 vfprintf(stderr, fmt, ap);
239 /*** Network-related utility functions ***************************************/
242 * Return the default port for a scheme
245 fetch_default_port(const char *scheme)
249 if ((se = getservbyname(scheme, "tcp")) != NULL)
250 return (ntohs(se->s_port));
251 if (strcmp(scheme, SCHEME_FTP) == 0)
252 return (FTP_DEFAULT_PORT);
253 if (strcmp(scheme, SCHEME_HTTP) == 0)
254 return (HTTP_DEFAULT_PORT);
259 * Return the default proxy port for a scheme
262 fetch_default_proxy_port(const char *scheme)
264 if (strcmp(scheme, SCHEME_FTP) == 0)
265 return (FTP_DEFAULT_PROXY_PORT);
266 if (strcmp(scheme, SCHEME_HTTP) == 0)
267 return (HTTP_DEFAULT_PROXY_PORT);
273 * Create a connection for an existing descriptor.
281 /* allocate and fill connection structure */
282 if ((conn = calloc(1, sizeof(*conn))) == NULL)
284 fcntl(sd, F_SETFD, FD_CLOEXEC);
285 setsockopt(sd, SOL_SOCKET, SO_NOSIGPIPE, &opt, sizeof opt);
293 * Bump a connection's reference count.
296 fetch_ref(conn_t *conn)
308 fetch_resolve(const char *addr, int port, int af)
310 char hbuf[256], sbuf[8];
311 struct addrinfo hints, *res;
312 const char *hb, *he, *sep;
313 const char *host, *service;
316 /* first, check for a bracketed IPv6 address */
319 if ((sep = strchr(hb, ']')) == NULL) {
326 sep = strchrnul(hb, ':');
330 /* see if we need to copy the host name */
332 len = snprintf(hbuf, sizeof(hbuf),
333 "%.*s", (int)(he - hb), hb);
336 if (len >= (int)sizeof(hbuf)) {
337 errno = ENAMETOOLONG;
345 /* was it followed by a service name? */
346 if (*sep == '\0' && port != 0) {
347 if (port < 1 || port > 65535) {
351 if (snprintf(sbuf, sizeof(sbuf), "%d", port) < 0)
354 } else if (*sep != '\0') {
361 memset(&hints, 0, sizeof(hints));
362 hints.ai_family = af;
363 hints.ai_socktype = SOCK_STREAM;
364 hints.ai_flags = AI_ADDRCONFIG;
365 if ((err = getaddrinfo(host, service, &hints, &res)) != 0) {
377 * Bind a socket to a specific local address
380 fetch_bind(int sd, int af, const char *addr)
382 struct addrinfo *cliai, *ai;
385 if ((cliai = fetch_resolve(addr, 0, af)) == NULL)
387 for (ai = cliai; ai != NULL; ai = ai->ai_next)
388 if ((err = bind(sd, ai->ai_addr, ai->ai_addrlen)) == 0)
393 return (err == 0 ? 0 : -1);
398 * SOCKS5 connection initiation, based on RFC 1928
399 * Default DNS resolution over SOCKS5
402 fetch_socks5_init(conn_t *conn, const char *host, int port, int verbose)
405 * Size is based on largest packet prefix (4 bytes) +
406 * Largest FQDN (256) + one byte size (1) +
409 unsigned char buf[BUFF_SIZE];
414 fetch_info("Initializing SOCKS5 connection: %s:%d", host, port);
416 /* Connection initialization */
418 *ptr++ = SOCKS_VERSION_5;
419 *ptr++ = SOCKS_CONNECTION;
422 if (fetch_write(conn, buf, 3) != 3) {
423 ret = SOCKS5_ERR_SELECTION;
427 /* Verify response from SOCKS5 server */
428 if (fetch_read(conn, buf, 2) != 2) {
429 ret = SOCKS5_ERR_READ_METHOD;
434 if (ptr[0] != SOCKS_VERSION_5) {
435 ret = SOCKS5_ERR_VER5_ONLY;
438 if (ptr[1] == SOCKS_NOMETHODS) {
439 ret = SOCKS5_ERR_NOMETHODS;
442 else if (ptr[1] != SOCKS5_NOTIMPLEMENTED) {
443 ret = SOCKS5_ERR_NOTIMPLEMENTED;
448 *ptr++ = SOCKS_VERSION_5;
449 *ptr++ = SOCKS_CONNECTION;
451 /* Encode all targets as a hostname to avoid DNS leaks */
452 *ptr++ = SOCKS_ATYP_DOMAINNAME;
453 if (strlen(host) > FQDN_SIZE) {
454 ret = SOCKS5_ERR_HOSTNAME_SIZE;
457 *ptr++ = strlen(host);
458 strncpy(ptr, host, strlen(host));
459 ptr = ptr + strlen(host);
462 *ptr++ = port & 0x00ff;
463 *ptr++ = (port & 0xff00) >> 8;
465 if (fetch_write(conn, buf, ptr - buf) != ptr - buf) {
466 ret = SOCKS5_ERR_REQUEST;
470 /* BND.ADDR is variable length, read the largest on non-blocking socket */
471 if (!fetch_read(conn, buf, BUFF_SIZE)) {
472 ret = SOCKS5_ERR_REPLY;
477 if (*ptr++ != SOCKS_VERSION_5) {
478 ret = SOCKS5_ERR_NON_VER5_RESP;
485 case SOCKS_GENERAL_FAILURE:
486 ret = SOCKS5_ERR_GENERAL;
488 case SOCKS_CONNECTION_NOT_ALLOWED:
489 ret = SOCKS5_ERR_NOT_ALLOWED;
491 case SOCKS_NETWORK_UNREACHABLE:
492 ret = SOCKS5_ERR_NET_UNREACHABLE;
494 case SOCKS_HOST_UNREACHABLE:
495 ret = SOCKS5_ERR_HOST_UNREACHABLE;
497 case SOCKS_CONNECTION_REFUSED:
498 ret = SOCKS5_ERR_CONN_REFUSED;
500 case SOCKS_TTL_EXPIRED:
501 ret = SOCKS5_ERR_TTL_EXPIRED;
503 case SOCKS_COMMAND_NOT_SUPPORTED:
504 ret = SOCKS5_ERR_COM_UNSUPPORTED;
506 case SOCKS_ADDRESS_NOT_SUPPORTED:
507 ret = SOCKS5_ERR_ADDR_UNSUPPORTED;
510 ret = SOCKS5_ERR_UNSPECIFIED;
522 * Perform SOCKS5 initialization
525 fetch_socks5_getenv(char **host, int *port)
527 char *socks5env, *endptr, *ext;
528 const char *portDelim;
532 if ((socks5env = getenv("SOCKS5_PROXY")) == NULL || *socks5env == '\0') {
539 * IPv6 addresses begin and end in brackets. Set the port delimiter
540 * accordingly and search for it so we can do appropriate validation.
542 if (socks5env[0] == '[')
545 slen = strlen(socks5env);
546 ext = strstr(socks5env, portDelim);
547 if (socks5env[0] == '[') {
548 if (socks5env[slen - 1] == ']') {
549 *host = strndup(socks5env, slen);
550 } else if (ext != NULL) {
551 *host = strndup(socks5env, ext - socks5env + 1);
553 socks5_seterr(SOCKS5_ERR_BAD_PROXY_FORMAT);
557 *host = strndup(socks5env, ext - socks5env);
563 *port = 1080; /* Default port as defined in RFC1928 */
565 ext += strlen(portDelim);
567 *port = strtoimax(ext, (char **)&endptr, 10);
568 if (*endptr != '\0' || errno != 0 || *port < 0 ||
570 socks5_seterr(SOCKS5_ERR_BAD_PORT);
578 fprintf(stderr, "Failure to allocate memory, exiting.\n");
584 * Establish a TCP connection to the specified port on the specified host.
587 fetch_connect(const char *host, int port, int af, int verbose)
589 struct addrinfo *cais = NULL, *sais = NULL, *cai, *sai;
590 const char *bindaddr;
592 int err = 0, sd = -1;
596 DEBUGF("---> %s:%d\n", host, port);
598 /* Check if SOCKS5_PROXY env variable is set */
599 if (!fetch_socks5_getenv(&sockshost, &socksport))
602 /* Not using SOCKS5 proxy */
603 if (sockshost == NULL) {
604 /* resolve server address */
606 fetch_info("resolving server address: %s:%d", host,
608 if ((sais = fetch_resolve(host, port, af)) == NULL)
611 /* resolve client address */
612 bindaddr = getenv("FETCH_BIND_ADDRESS");
613 if (bindaddr != NULL && *bindaddr != '\0') {
615 fetch_info("resolving client address: %s",
617 if ((cais = fetch_resolve(bindaddr, 0, af)) == NULL)
621 /* resolve socks5 proxy address */
623 fetch_info("resolving SOCKS5 server address: %s:%d",
624 sockshost, socksport);
625 if ((sais = fetch_resolve(sockshost, socksport, af)) == NULL) {
626 socks5_seterr(SOCKS5_ERR_BAD_HOST);
631 /* try each server address in turn */
632 for (err = 0, sai = sais; sai != NULL; sai = sai->ai_next) {
634 if ((sd = socket(sai->ai_family, SOCK_STREAM, 0)) < 0)
636 /* attempt to bind to client address */
637 for (err = 0, cai = cais; cai != NULL; cai = cai->ai_next) {
638 if (cai->ai_family != sai->ai_family)
640 if ((err = bind(sd, cai->ai_addr, cai->ai_addrlen)) == 0)
645 fetch_info("failed to bind to %s", bindaddr);
648 /* attempt to connect to server address */
649 if ((err = connect(sd, sai->ai_addr, sai->ai_addrlen)) == 0)
651 /* clean up before next attempt */
656 if (verbose && sockshost == NULL) {
657 fetch_info("failed to connect to %s:%d", host, port);
659 } else if (sockshost != NULL) {
662 "failed to connect to SOCKS5 server %s:%d",
663 sockshost, socksport);
664 socks5_seterr(SOCKS5_ERR_CONN_REFUSED);
670 if ((conn = fetch_reopen(sd)) == NULL)
674 if (!fetch_socks5_init(conn, host, port, verbose))
697 * Convert characters A-Z to lowercase (intentionally avoid any locale
698 * specific conversions).
701 fetch_ssl_tolower(char in)
703 if (in >= 'A' && in <= 'Z')
710 * isalpha implementation that intentionally avoids any locale specific
714 fetch_ssl_isalpha(char in)
716 return ((in >= 'A' && in <= 'Z') || (in >= 'a' && in <= 'z'));
720 * Check if passed hostnames a and b are equal.
723 fetch_ssl_hname_equal(const char *a, size_t alen, const char *b,
730 for (i = 0; i < alen; ++i) {
731 if (fetch_ssl_tolower(a[i]) != fetch_ssl_tolower(b[i]))
738 * Check if domain label is traditional, meaning that only A-Z, a-z, 0-9
739 * and '-' (hyphen) are allowed. Hyphens have to be surrounded by alpha-
740 * numeric characters. Double hyphens (like they're found in IDN a-labels
741 * 'xn--') are not allowed. Empty labels are invalid.
744 fetch_ssl_is_trad_domain_label(const char *l, size_t len, int wcok)
748 if (!len || l[0] == '-' || l[len-1] == '-')
750 for (i = 0; i < len; ++i) {
751 if (!isdigit(l[i]) &&
752 !fetch_ssl_isalpha(l[i]) &&
753 !(l[i] == '*' && wcok) &&
754 !(l[i] == '-' && l[i - 1] != '-'))
761 * Check if host name consists only of numbers. This might indicate an IP
762 * address, which is not a good idea for CN wildcard comparison.
765 fetch_ssl_hname_is_only_numbers(const char *hostname, size_t len)
769 for (i = 0; i < len; ++i) {
770 if (!((hostname[i] >= '0' && hostname[i] <= '9') ||
778 * Check if the host name h passed matches the pattern passed in m which
779 * is usually part of subjectAltName or CN of a certificate presented to
780 * the client. This includes wildcard matching. The algorithm is based on
781 * RFC6125, sections 6.4.3 and 7.2, which clarifies RFC2818 and RFC3280.
784 fetch_ssl_hname_match(const char *h, size_t hlen, const char *m,
787 int delta, hdotidx, mdot1idx, wcidx;
788 const char *hdot, *mdot1, *mdot2;
789 const char *wc; /* wildcard */
791 if (!(h && *h && m && *m))
793 if ((wc = strnstr(m, "*", mlen)) == NULL)
794 return (fetch_ssl_hname_equal(h, hlen, m, mlen));
796 /* hostname should not be just dots and numbers */
797 if (fetch_ssl_hname_is_only_numbers(h, hlen))
799 /* only one wildcard allowed in pattern */
800 if (strnstr(wc + 1, "*", mlen - wcidx - 1) != NULL)
803 * there must be at least two more domain labels and
804 * wildcard has to be in the leftmost label (RFC6125)
806 mdot1 = strnstr(m, ".", mlen);
807 if (mdot1 == NULL || mdot1 < wc || (mlen - (mdot1 - m)) < 4)
809 mdot1idx = mdot1 - m;
810 mdot2 = strnstr(mdot1 + 1, ".", mlen - mdot1idx - 1);
811 if (mdot2 == NULL || (mlen - (mdot2 - m)) < 2)
813 /* hostname must contain a dot and not be the 1st char */
814 hdot = strnstr(h, ".", hlen);
815 if (hdot == NULL || hdot == h)
819 * host part of hostname must be at least as long as
820 * pattern it's supposed to match
822 if (hdotidx < mdot1idx)
825 * don't allow wildcards in non-traditional domain names
826 * (IDN, A-label, U-label...)
828 if (!fetch_ssl_is_trad_domain_label(h, hdotidx, 0) ||
829 !fetch_ssl_is_trad_domain_label(m, mdot1idx, 1))
831 /* match domain part (part after first dot) */
832 if (!fetch_ssl_hname_equal(hdot, hlen - hdotidx, mdot1,
835 /* match part left of wildcard */
836 if (!fetch_ssl_hname_equal(h, wcidx, m, wcidx))
838 /* match part right of wildcard */
839 delta = mdot1idx - wcidx - 1;
840 if (!fetch_ssl_hname_equal(hdot - delta, delta,
841 mdot1 - delta, delta))
843 /* all tests succeeded, it's a match */
848 * Get numeric host address info - returns NULL if host was not an IP
849 * address. The caller is responsible for deallocation using
852 static struct addrinfo *
853 fetch_ssl_get_numeric_addrinfo(const char *hostname, size_t len)
855 struct addrinfo hints, *res;
858 host = (char *)malloc(len + 1);
859 memcpy(host, hostname, len);
861 memset(&hints, 0, sizeof(hints));
862 hints.ai_family = PF_UNSPEC;
863 hints.ai_socktype = SOCK_STREAM;
864 hints.ai_protocol = 0;
865 hints.ai_flags = AI_NUMERICHOST;
866 /* port is not relevant for this purpose */
867 if (getaddrinfo(host, "443", &hints, &res) != 0)
874 * Compare ip address in addrinfo with address passes.
877 fetch_ssl_ipaddr_match_bin(const struct addrinfo *lhost, const char *rhost,
882 if (lhost->ai_family == AF_INET && rhostlen == 4) {
883 left = (void *)&((struct sockaddr_in*)(void *)
884 lhost->ai_addr)->sin_addr.s_addr;
886 } else if (lhost->ai_family == AF_INET6 && rhostlen == 16) {
887 left = (void *)&((struct sockaddr_in6 *)(void *)
888 lhost->ai_addr)->sin6_addr;
892 return (!memcmp(left, (const void *)rhost, rhostlen) ? 1 : 0);
896 * Compare ip address in addrinfo with host passed. If host is not an IP
897 * address, comparison will fail.
900 fetch_ssl_ipaddr_match(const struct addrinfo *laddr, const char *r,
903 struct addrinfo *raddr;
908 if ((raddr = fetch_ssl_get_numeric_addrinfo(r, rlen)) == NULL)
909 return 0; /* not a numeric host */
911 if (laddr->ai_family == raddr->ai_family) {
912 if (laddr->ai_family == AF_INET) {
913 rip = (char *)&((struct sockaddr_in *)(void *)
914 raddr->ai_addr)->sin_addr.s_addr;
915 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 4);
917 } else if (laddr->ai_family == AF_INET6) {
918 rip = (char *)&((struct sockaddr_in6 *)(void *)
919 raddr->ai_addr)->sin6_addr;
920 ret = fetch_ssl_ipaddr_match_bin(laddr, rip, 16);
930 * Verify server certificate by subjectAltName.
933 fetch_ssl_verify_altname(STACK_OF(GENERAL_NAME) *altnames,
934 const char *host, struct addrinfo *ip)
936 const GENERAL_NAME *name;
941 for (i = 0; i < sk_GENERAL_NAME_num(altnames); ++i) {
942 #if OPENSSL_VERSION_NUMBER < 0x10000000L
944 * This is a workaround, since the following line causes
945 * alignment issues in clang:
946 * name = sk_GENERAL_NAME_value(altnames, i);
947 * OpenSSL explicitly warns not to use those macros
948 * directly, but there isn't much choice (and there
949 * shouldn't be any ill side effects)
951 name = (GENERAL_NAME *)SKM_sk_value(void, altnames, i);
953 name = sk_GENERAL_NAME_value(altnames, i);
955 #if OPENSSL_VERSION_NUMBER < 0x10100000L
956 ns = (const char *)ASN1_STRING_data(name->d.ia5);
958 ns = (const char *)ASN1_STRING_get0_data(name->d.ia5);
960 nslen = (size_t)ASN1_STRING_length(name->d.ia5);
962 if (name->type == GEN_DNS && ip == NULL &&
963 fetch_ssl_hname_match(host, strlen(host), ns, nslen))
965 else if (name->type == GEN_IPADD && ip != NULL &&
966 fetch_ssl_ipaddr_match_bin(ip, ns, nslen))
973 * Verify server certificate by CN.
976 fetch_ssl_verify_cn(X509_NAME *subject, const char *host,
979 ASN1_STRING *namedata;
980 X509_NAME_ENTRY *nameentry;
981 int cnlen, lastpos, loc, ret;
988 /* get most specific CN (last entry in list) and compare */
989 while ((lastpos = X509_NAME_get_index_by_NID(subject,
990 NID_commonName, lastpos)) != -1)
994 nameentry = X509_NAME_get_entry(subject, loc);
995 namedata = X509_NAME_ENTRY_get_data(nameentry);
996 cnlen = ASN1_STRING_to_UTF8(&cn, namedata);
998 fetch_ssl_hname_match(host, strlen(host), cn, cnlen))
1000 else if (ip != NULL && fetch_ssl_ipaddr_match(ip, cn, cnlen))
1008 * Verify that server certificate subjectAltName/CN matches
1009 * hostname. First check, if there are alternative subject names. If yes,
1010 * those have to match. Only if those don't exist it falls back to
1011 * checking the subject's CN.
1014 fetch_ssl_verify_hname(X509 *cert, const char *host)
1016 struct addrinfo *ip;
1017 STACK_OF(GENERAL_NAME) *altnames;
1022 ip = fetch_ssl_get_numeric_addrinfo(host, strlen(host));
1023 altnames = X509_get_ext_d2i(cert, NID_subject_alt_name,
1026 if (altnames != NULL) {
1027 ret = fetch_ssl_verify_altname(altnames, host, ip);
1029 subject = X509_get_subject_name(cert);
1030 if (subject != NULL)
1031 ret = fetch_ssl_verify_cn(subject, host, ip);
1036 if (altnames != NULL)
1037 GENERAL_NAMES_free(altnames);
1042 * Configure transport security layer based on environment.
1045 fetch_ssl_setup_transport_layer(SSL_CTX *ctx, int verbose)
1047 long ssl_ctx_options;
1049 ssl_ctx_options = SSL_OP_ALL | SSL_OP_NO_SSLv2 | SSL_OP_NO_TICKET;
1050 if (getenv("SSL_ALLOW_SSL3") == NULL)
1051 ssl_ctx_options |= SSL_OP_NO_SSLv3;
1052 if (getenv("SSL_NO_TLS1") != NULL)
1053 ssl_ctx_options |= SSL_OP_NO_TLSv1;
1054 if (getenv("SSL_NO_TLS1_1") != NULL)
1055 ssl_ctx_options |= SSL_OP_NO_TLSv1_1;
1056 if (getenv("SSL_NO_TLS1_2") != NULL)
1057 ssl_ctx_options |= SSL_OP_NO_TLSv1_2;
1059 fetch_info("SSL options: %lx", ssl_ctx_options);
1060 SSL_CTX_set_options(ctx, ssl_ctx_options);
1065 * Configure peer verification based on environment.
1067 #define LOCAL_CERT_FILE "/usr/local/etc/ssl/cert.pem"
1068 #define BASE_CERT_FILE "/etc/ssl/cert.pem"
1070 fetch_ssl_setup_peer_verification(SSL_CTX *ctx, int verbose)
1072 X509_LOOKUP *crl_lookup;
1073 X509_STORE *crl_store;
1074 const char *ca_cert_file, *ca_cert_path, *crl_file;
1076 if (getenv("SSL_NO_VERIFY_PEER") == NULL) {
1077 ca_cert_file = getenv("SSL_CA_CERT_FILE");
1078 if (ca_cert_file == NULL &&
1079 access(LOCAL_CERT_FILE, R_OK) == 0)
1080 ca_cert_file = LOCAL_CERT_FILE;
1081 if (ca_cert_file == NULL &&
1082 access(BASE_CERT_FILE, R_OK) == 0)
1083 ca_cert_file = BASE_CERT_FILE;
1084 ca_cert_path = getenv("SSL_CA_CERT_PATH");
1086 fetch_info("Peer verification enabled");
1087 if (ca_cert_file != NULL)
1088 fetch_info("Using CA cert file: %s",
1090 if (ca_cert_path != NULL)
1091 fetch_info("Using CA cert path: %s",
1093 if (ca_cert_file == NULL && ca_cert_path == NULL)
1094 fetch_info("Using OpenSSL default "
1095 "CA cert file and path");
1097 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
1098 fetch_ssl_cb_verify_crt);
1099 if (ca_cert_file != NULL || ca_cert_path != NULL)
1100 SSL_CTX_load_verify_locations(ctx, ca_cert_file,
1103 SSL_CTX_set_default_verify_paths(ctx);
1104 if ((crl_file = getenv("SSL_CRL_FILE")) != NULL) {
1106 fetch_info("Using CRL file: %s", crl_file);
1107 crl_store = SSL_CTX_get_cert_store(ctx);
1108 crl_lookup = X509_STORE_add_lookup(crl_store,
1109 X509_LOOKUP_file());
1110 if (crl_lookup == NULL ||
1111 !X509_load_crl_file(crl_lookup, crl_file,
1112 X509_FILETYPE_PEM)) {
1114 "Could not load CRL file %s\n",
1118 X509_STORE_set_flags(crl_store,
1119 X509_V_FLAG_CRL_CHECK |
1120 X509_V_FLAG_CRL_CHECK_ALL);
1127 * Configure client certificate based on environment.
1130 fetch_ssl_setup_client_certificate(SSL_CTX *ctx, int verbose)
1132 const char *client_cert_file, *client_key_file;
1134 if ((client_cert_file = getenv("SSL_CLIENT_CERT_FILE")) != NULL) {
1135 client_key_file = getenv("SSL_CLIENT_KEY_FILE") != NULL ?
1136 getenv("SSL_CLIENT_KEY_FILE") : client_cert_file;
1138 fetch_info("Using client cert file: %s",
1140 fetch_info("Using client key file: %s",
1143 if (SSL_CTX_use_certificate_chain_file(ctx,
1144 client_cert_file) != 1) {
1146 "Could not load client certificate %s\n",
1150 if (SSL_CTX_use_PrivateKey_file(ctx, client_key_file,
1151 SSL_FILETYPE_PEM) != 1) {
1153 "Could not load client key %s\n",
1162 * Callback for SSL certificate verification, this is called on server
1163 * cert verification. It takes no decision, but informs the user in case
1164 * verification failed.
1167 fetch_ssl_cb_verify_crt(int verified, X509_STORE_CTX *ctx)
1175 if ((crt = X509_STORE_CTX_get_current_cert(ctx)) != NULL &&
1176 (name = X509_get_subject_name(crt)) != NULL)
1177 str = X509_NAME_oneline(name, 0, 0);
1178 fprintf(stderr, "Certificate verification failed for %s\n",
1179 str != NULL ? str : "no relevant certificate");
1188 * Enable SSL on a connection.
1191 fetch_ssl(conn_t *conn, const struct url *URL, int verbose)
1198 /* Init the SSL library and context */
1199 if (!SSL_library_init()){
1200 fprintf(stderr, "SSL library init failed\n");
1204 SSL_load_error_strings();
1206 conn->ssl_meth = SSLv23_client_method();
1207 conn->ssl_ctx = SSL_CTX_new(conn->ssl_meth);
1208 SSL_CTX_set_mode(conn->ssl_ctx, SSL_MODE_AUTO_RETRY);
1210 fetch_ssl_setup_transport_layer(conn->ssl_ctx, verbose);
1211 if (!fetch_ssl_setup_peer_verification(conn->ssl_ctx, verbose))
1213 if (!fetch_ssl_setup_client_certificate(conn->ssl_ctx, verbose))
1216 conn->ssl = SSL_new(conn->ssl_ctx);
1217 if (conn->ssl == NULL) {
1218 fprintf(stderr, "SSL context creation failed\n");
1221 SSL_set_fd(conn->ssl, conn->sd);
1223 #if OPENSSL_VERSION_NUMBER >= 0x0090806fL && !defined(OPENSSL_NO_TLSEXT)
1224 if (!SSL_set_tlsext_host_name(conn->ssl,
1225 __DECONST(struct url *, URL)->host)) {
1227 "TLS server name indication extension failed for host %s\n",
1232 while ((ret = SSL_connect(conn->ssl)) == -1) {
1233 ssl_err = SSL_get_error(conn->ssl, ret);
1234 if (ssl_err != SSL_ERROR_WANT_READ &&
1235 ssl_err != SSL_ERROR_WANT_WRITE) {
1236 ERR_print_errors_fp(stderr);
1240 conn->ssl_cert = SSL_get_peer_certificate(conn->ssl);
1242 if (conn->ssl_cert == NULL) {
1243 fprintf(stderr, "No server SSL certificate\n");
1247 if (getenv("SSL_NO_VERIFY_HOSTNAME") == NULL) {
1249 fetch_info("Verify hostname");
1250 if (!fetch_ssl_verify_hname(conn->ssl_cert, URL->host)) {
1252 "SSL certificate subject doesn't match host %s\n",
1259 fetch_info("%s connection established using %s",
1260 SSL_get_version(conn->ssl), SSL_get_cipher(conn->ssl));
1261 name = X509_get_subject_name(conn->ssl_cert);
1262 str = X509_NAME_oneline(name, 0, 0);
1263 fetch_info("Certificate subject: %s", str);
1265 name = X509_get_issuer_name(conn->ssl_cert);
1266 str = X509_NAME_oneline(name, 0, 0);
1267 fetch_info("Certificate issuer: %s", str);
1276 fprintf(stderr, "SSL support disabled\n");
1281 #define FETCH_READ_WAIT -2
1282 #define FETCH_READ_ERROR -1
1283 #define FETCH_READ_DONE 0
1287 fetch_ssl_read(SSL *ssl, char *buf, size_t len)
1292 rlen = SSL_read(ssl, buf, len);
1294 ssl_err = SSL_get_error(ssl, rlen);
1295 if (ssl_err == SSL_ERROR_WANT_READ ||
1296 ssl_err == SSL_ERROR_WANT_WRITE) {
1297 return (FETCH_READ_WAIT);
1299 ERR_print_errors_fp(stderr);
1300 return (FETCH_READ_ERROR);
1308 fetch_socket_read(int sd, char *buf, size_t len)
1312 rlen = read(sd, buf, len);
1314 if (errno == EAGAIN || (errno == EINTR && fetchRestartCalls))
1315 return (FETCH_READ_WAIT);
1317 return (FETCH_READ_ERROR);
1323 * Read a character from a connection w/ timeout
1326 fetch_read(conn_t *conn, char *buf, size_t len)
1328 struct timeval now, timeout, delta;
1333 if (fetchTimeout > 0) {
1334 gettimeofday(&timeout, NULL);
1335 timeout.tv_sec += fetchTimeout;
1339 memset(&pfd, 0, sizeof pfd);
1341 pfd.events = POLLIN | POLLERR;
1345 * The socket is non-blocking. Instead of the canonical
1346 * poll() -> read(), we do the following:
1348 * 1) call read() or SSL_read().
1349 * 2) if we received some data, return it.
1350 * 3) if an error occurred, return -1.
1351 * 4) if read() or SSL_read() signaled EOF, return.
1352 * 5) if we did not receive any data but we're not at EOF,
1355 * In the SSL case, this is necessary because if we
1356 * receive a close notification, we have to call
1357 * SSL_read() one additional time after we've read
1358 * everything we received.
1360 * In the non-SSL case, it may improve performance (very
1361 * slightly) when reading small amounts of data.
1364 if (conn->ssl != NULL)
1365 rlen = fetch_ssl_read(conn->ssl, buf, len);
1368 rlen = fetch_socket_read(conn->sd, buf, len);
1371 } else if (rlen == FETCH_READ_ERROR) {
1375 // assert(rlen == FETCH_READ_WAIT);
1376 if (fetchTimeout > 0) {
1377 gettimeofday(&now, NULL);
1378 if (!timercmp(&timeout, &now, >)) {
1383 timersub(&timeout, &now, &delta);
1384 deltams = delta.tv_sec * 1000 +
1385 delta.tv_usec / 1000;;
1389 if (poll(&pfd, 1, deltams) < 0) {
1390 if (errno == EINTR && fetchRestartCalls)
1401 * Read a line of text from a connection w/ timeout
1403 #define MIN_BUF_SIZE 1024
1406 fetch_getln(conn_t *conn)
1413 if (conn->buf == NULL) {
1414 if ((conn->buf = malloc(MIN_BUF_SIZE)) == NULL) {
1418 conn->bufsize = MIN_BUF_SIZE;
1421 conn->buf[0] = '\0';
1425 len = fetch_read(conn, &c, 1);
1430 conn->buf[conn->buflen++] = c;
1431 if (conn->buflen == conn->bufsize) {
1433 tmpsize = conn->bufsize * 2 + 1;
1434 if ((tmp = realloc(tmp, tmpsize)) == NULL) {
1439 conn->bufsize = tmpsize;
1441 } while (c != '\n');
1443 conn->buf[conn->buflen] = '\0';
1444 DEBUGF("<<< %s", conn->buf);
1450 * Write to a connection w/ timeout
1453 fetch_write(conn_t *conn, const char *buf, size_t len)
1457 iov.iov_base = __DECONST(char *, buf);
1459 return fetch_writev(conn, &iov, 1);
1463 * Write a vector to a connection w/ timeout
1464 * Note: can modify the iovec.
1467 fetch_writev(conn_t *conn, struct iovec *iov, int iovcnt)
1469 struct timeval now, timeout, delta;
1471 ssize_t wlen, total;
1474 memset(&pfd, 0, sizeof pfd);
1477 pfd.events = POLLOUT | POLLERR;
1478 gettimeofday(&timeout, NULL);
1479 timeout.tv_sec += fetchTimeout;
1483 while (iovcnt > 0) {
1484 while (fetchTimeout && pfd.revents == 0) {
1485 gettimeofday(&now, NULL);
1486 if (!timercmp(&timeout, &now, >)) {
1491 timersub(&timeout, &now, &delta);
1492 deltams = delta.tv_sec * 1000 +
1493 delta.tv_usec / 1000;
1496 if (poll(&pfd, 1, deltams) < 0) {
1497 /* POSIX compliance */
1498 if (errno == EAGAIN)
1500 if (errno == EINTR && fetchRestartCalls)
1507 if (conn->ssl != NULL)
1508 wlen = SSL_write(conn->ssl,
1509 iov->iov_base, iov->iov_len);
1512 wlen = writev(conn->sd, iov, iovcnt);
1514 /* we consider a short write a failure */
1515 /* XXX perhaps we shouldn't in the SSL case */
1521 if (errno == EINTR && fetchRestartCalls)
1526 while (iovcnt > 0 && wlen >= (ssize_t)iov->iov_len) {
1527 wlen -= iov->iov_len;
1532 iov->iov_len -= wlen;
1533 iov->iov_base = __DECONST(char *, iov->iov_base) + wlen;
1541 * Write a line of text to a connection w/ timeout
1544 fetch_putln(conn_t *conn, const char *str, size_t len)
1546 struct iovec iov[2];
1549 DEBUGF(">>> %s\n", str);
1550 iov[0].iov_base = __DECONST(char *, str);
1551 iov[0].iov_len = len;
1552 iov[1].iov_base = __DECONST(char *, ENDL);
1553 iov[1].iov_len = sizeof(ENDL);
1555 ret = fetch_writev(conn, &iov[1], 1);
1557 ret = fetch_writev(conn, iov, 2);
1568 fetch_close(conn_t *conn)
1572 if (--conn->ref > 0)
1576 SSL_shutdown(conn->ssl);
1577 SSL_set_connect_state(conn->ssl);
1578 SSL_free(conn->ssl);
1581 if (conn->ssl_ctx) {
1582 SSL_CTX_free(conn->ssl_ctx);
1583 conn->ssl_ctx = NULL;
1585 if (conn->ssl_cert) {
1586 X509_free(conn->ssl_cert);
1587 conn->ssl_cert = NULL;
1590 ret = close(conn->sd);
1597 /*** Directory-related utility functions *************************************/
1600 fetch_add_entry(struct url_ent **p, int *size, int *len,
1601 const char *name, struct url_stat *us)
1603 struct url_ent *tmp;
1610 if (*len >= *size - 1) {
1611 tmp = reallocarray(*p, *size * 2 + 1, sizeof(**p));
1617 *size = (*size * 2 + 1);
1622 snprintf(tmp->name, PATH_MAX, "%s", name);
1623 memcpy(&tmp->stat, us, sizeof(*us));
1626 (++tmp)->name[0] = 0;
1632 /*** Authentication-related utility functions ********************************/
1635 fetch_read_word(FILE *f)
1637 static char word[1024];
1639 if (fscanf(f, " %1023s ", word) != 1)
1645 fetch_netrc_open(void)
1652 if ((p = getenv("NETRC")) != NULL) {
1653 DEBUGF("NETRC=%s\n", p);
1654 if (snprintf(fn, sizeof(fn), "%s", p) >= (int)sizeof(fn)) {
1655 fetch_info("$NETRC specifies a file name "
1656 "longer than PATH_MAX");
1660 if ((p = getenv("HOME")) == NULL) {
1661 if ((pwd = getpwuid(getuid())) == NULL ||
1662 (p = pwd->pw_dir) == NULL)
1665 if (snprintf(fn, sizeof(fn), "%s/.netrc", p) >= (int)sizeof(fn))
1669 if ((fd = open(fn, O_RDONLY)) < 0) {
1671 DEBUGF("%s: %s\n", fn, strerror(serrno));
1678 * Get authentication data for a URL from .netrc
1681 fetch_netrc_auth(struct url *url)
1687 if (url->netrcfd < 0)
1688 url->netrcfd = fetch_netrc_open();
1689 if (url->netrcfd < 0)
1691 if ((f = fdopen(url->netrcfd, "r")) == NULL) {
1693 DEBUGF("fdopen(netrcfd): %s", strerror(errno));
1694 close(url->netrcfd);
1700 DEBUGF("searching netrc for %s\n", url->host);
1701 while ((word = fetch_read_word(f)) != NULL) {
1702 if (strcmp(word, "default") == 0) {
1703 DEBUGF("using default netrc settings\n");
1706 if (strcmp(word, "machine") == 0 &&
1707 (word = fetch_read_word(f)) != NULL &&
1708 strcasecmp(word, url->host) == 0) {
1709 DEBUGF("using netrc settings for %s\n", word);
1715 while ((word = fetch_read_word(f)) != NULL) {
1716 if (strcmp(word, "login") == 0) {
1717 if ((word = fetch_read_word(f)) == NULL)
1719 if (snprintf(url->user, sizeof(url->user),
1720 "%s", word) > (int)sizeof(url->user)) {
1721 fetch_info("login name in .netrc is too long");
1722 url->user[0] = '\0';
1724 } else if (strcmp(word, "password") == 0) {
1725 if ((word = fetch_read_word(f)) == NULL)
1727 if (snprintf(url->pwd, sizeof(url->pwd),
1728 "%s", word) > (int)sizeof(url->pwd)) {
1729 fetch_info("password in .netrc is too long");
1732 } else if (strcmp(word, "account") == 0) {
1733 if ((word = fetch_read_word(f)) == NULL)
1735 /* XXX not supported! */
1752 * The no_proxy environment variable specifies a set of domains for
1753 * which the proxy should not be consulted; the contents is a comma-,
1754 * or space-separated list of domain names. A single asterisk will
1755 * override all proxy variables and no transactions will be proxied
1756 * (for compatibility with lynx and curl, see the discussion at
1757 * <http://curl.haxx.se/mail/archive_pre_oct_99/0009.html>).
1760 fetch_no_proxy_match(const char *host)
1762 const char *no_proxy, *p, *q;
1763 size_t h_len, d_len;
1765 if ((no_proxy = getenv("NO_PROXY")) == NULL &&
1766 (no_proxy = getenv("no_proxy")) == NULL)
1769 /* asterisk matches any hostname */
1770 if (strcmp(no_proxy, "*") == 0)
1773 h_len = strlen(host);
1776 /* position p at the beginning of a domain suffix */
1777 while (*p == ',' || isspace((unsigned char)*p))
1780 /* position q at the first separator character */
1781 for (q = p; *q; ++q)
1782 if (*q == ',' || isspace((unsigned char)*q))
1786 if (d_len > 0 && h_len >= d_len &&
1787 strncasecmp(host + h_len - d_len,
1789 /* domain name matches */