1 /* $OpenBSD: ssh.c,v 1.475 2018/02/23 15:58:38 markus Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * Ssh client program. This program can be used to log into a remote machine.
7 * The software supports strong authentication, encryption, and forwarding
8 * of X11, TCP/IP, and authentication connections.
10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
16 * Copyright (c) 1999 Niels Provos. All rights reserved.
17 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
19 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20 * in Canada (German citizen).
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
31 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
46 #include <sys/types.h>
47 #ifdef HAVE_SYS_STAT_H
48 # include <sys/stat.h>
50 #include <sys/resource.h>
51 #include <sys/ioctl.h>
52 #include <sys/socket.h>
73 #include <netinet/in.h>
74 #include <arpa/inet.h>
77 #include <openssl/evp.h>
78 #include <openssl/err.h>
80 #include "openbsd-compat/openssl-compat.h"
81 #include "openbsd-compat/sys-queue.h"
96 #include "pathnames.h"
98 #include "clientloop.h"
101 #include "readconf.h"
102 #include "sshconnect.h"
111 #include "myproposal.h"
115 #include "ssh-pkcs11.h"
118 extern char *__progname;
120 /* Saves a copy of argv for setproctitle emulation */
121 #ifndef HAVE_SETPROCTITLE
122 static char **saved_av;
125 /* Flag indicating whether debug mode is on. May be set on the command line. */
128 /* Flag indicating whether a tty should be requested */
131 /* don't exec a shell */
132 int no_shell_flag = 0;
135 * Flag indicating that nothing should be read from stdin. This can be set
136 * on the command line.
138 int stdin_null_flag = 0;
141 * Flag indicating that the current process should be backgrounded and
142 * a new slave launched in the foreground for ControlPersist.
144 int need_controlpersist_detach = 0;
146 /* Copies of flags for ControlPersist foreground slave */
147 int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
150 * Flag indicating that ssh should fork after authentication. This is useful
151 * so that the passphrase can be entered manually, and then ssh goes to the
154 int fork_after_authentication_flag = 0;
157 * General data structure for command line options and options configurable
158 * in configuration files. See readconf.h.
162 /* optional user configfile */
166 * Name of the host we are connecting to. This is the name given on the
167 * command line, or the HostName specified for the user-supplied name in a
168 * configuration file.
172 /* Various strings used to to percent_expand() arguments */
173 static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
174 static char uidstr[32], *host_arg, *conn_hash_hex;
176 /* socket address the host resolves to */
177 struct sockaddr_storage hostaddr;
179 /* Private host keys. */
180 Sensitive sensitive_data;
182 /* Original real UID. */
183 uid_t original_real_uid;
184 uid_t original_effective_uid;
186 /* command to be executed */
189 /* Should we execute a command or invoke a subsystem? */
190 int subsystem_flag = 0;
192 /* # of replies received for global requests */
193 static int remote_forward_confirms_received = 0;
196 extern int muxserver_sock;
197 extern u_int muxclient_command;
199 /* Prints a help message to the user. This function never returns. */
205 "usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n"
206 " [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n"
207 " [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n"
208 " [-i identity_file] [-J [user@]host[:port]] [-L address]\n"
209 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
210 " [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n"
211 " [-w local_tun[:remote_tun]] destination [command]\n"
216 static int ssh_session2(struct ssh *, struct passwd *);
217 static void load_public_identity_files(struct passwd *);
218 static void main_sigchld_handler(int);
220 /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
222 tilde_expand_paths(char **paths, u_int num_paths)
227 for (i = 0; i < num_paths; i++) {
228 cp = tilde_expand_filename(paths[i], original_real_uid);
235 * Attempt to resolve a host name / port to a set of addresses and
236 * optionally return any CNAMEs encountered along the way.
237 * Returns NULL on failure.
238 * NB. this function must operate with a options having undefined members.
240 static struct addrinfo *
241 resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
243 char strport[NI_MAXSERV];
244 struct addrinfo hints, *res;
245 int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1;
248 port = default_ssh_port();
250 snprintf(strport, sizeof strport, "%d", port);
251 memset(&hints, 0, sizeof(hints));
252 hints.ai_family = options.address_family == -1 ?
253 AF_UNSPEC : options.address_family;
254 hints.ai_socktype = SOCK_STREAM;
256 hints.ai_flags = AI_CANONNAME;
257 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
258 if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
259 loglevel = SYSLOG_LEVEL_ERROR;
260 do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
261 __progname, name, ssh_gai_strerror(gaierr));
264 if (cname != NULL && res->ai_canonname != NULL) {
265 if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
266 error("%s: host \"%s\" cname \"%s\" too long (max %lu)",
267 __func__, name, res->ai_canonname, (u_long)clen);
275 /* Returns non-zero if name can only be an address and not a hostname */
277 is_addr_fast(const char *name)
279 return (strchr(name, '%') != NULL || strchr(name, ':') != NULL ||
280 strspn(name, "0123456789.") == strlen(name));
283 /* Returns non-zero if name represents a valid, single address */
285 is_addr(const char *name)
287 char strport[NI_MAXSERV];
288 struct addrinfo hints, *res;
290 if (is_addr_fast(name))
293 snprintf(strport, sizeof strport, "%u", default_ssh_port());
294 memset(&hints, 0, sizeof(hints));
295 hints.ai_family = options.address_family == -1 ?
296 AF_UNSPEC : options.address_family;
297 hints.ai_socktype = SOCK_STREAM;
298 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
299 if (getaddrinfo(name, strport, &hints, &res) != 0)
301 if (res == NULL || res->ai_next != NULL) {
310 * Attempt to resolve a numeric host address / port to a single address.
311 * Returns a canonical address string.
312 * Returns NULL on failure.
313 * NB. this function must operate with a options having undefined members.
315 static struct addrinfo *
316 resolve_addr(const char *name, int port, char *caddr, size_t clen)
318 char addr[NI_MAXHOST], strport[NI_MAXSERV];
319 struct addrinfo hints, *res;
323 port = default_ssh_port();
324 snprintf(strport, sizeof strport, "%u", port);
325 memset(&hints, 0, sizeof(hints));
326 hints.ai_family = options.address_family == -1 ?
327 AF_UNSPEC : options.address_family;
328 hints.ai_socktype = SOCK_STREAM;
329 hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
330 if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
331 debug2("%s: could not resolve name %.100s as address: %s",
332 __func__, name, ssh_gai_strerror(gaierr));
336 debug("%s: getaddrinfo %.100s returned no addresses",
340 if (res->ai_next != NULL) {
341 debug("%s: getaddrinfo %.100s returned multiple addresses",
345 if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
346 addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
347 debug("%s: Could not format address for name %.100s: %s",
348 __func__, name, ssh_gai_strerror(gaierr));
351 if (strlcpy(caddr, addr, clen) >= clen) {
352 error("%s: host \"%s\" addr \"%s\" too long (max %lu)",
353 __func__, name, addr, (u_long)clen);
364 * Check whether the cname is a permitted replacement for the hostname
365 * and perform the replacement if it is.
366 * NB. this function must operate with a options having undefined members.
369 check_follow_cname(int direct, char **namep, const char *cname)
372 struct allowed_cname *rule;
374 if (*cname == '\0' || options.num_permitted_cnames == 0 ||
375 strcmp(*namep, cname) == 0)
377 if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
380 * Don't attempt to canonicalize names that will be interpreted by
381 * a proxy or jump host unless the user specifically requests so.
384 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
386 debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname);
387 for (i = 0; i < options.num_permitted_cnames; i++) {
388 rule = options.permitted_cnames + i;
389 if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
390 match_pattern_list(cname, rule->target_list, 1) != 1)
392 verbose("Canonicalized DNS aliased hostname "
393 "\"%s\" => \"%s\"", *namep, cname);
395 *namep = xstrdup(cname);
402 * Attempt to resolve the supplied hostname after applying the user's
403 * canonicalization rules. Returns the address list for the host or NULL
404 * if no name was found after canonicalization.
405 * NB. this function must operate with a options having undefined members.
407 static struct addrinfo *
408 resolve_canonicalize(char **hostp, int port)
410 int i, direct, ndots;
411 char *cp, *fullhost, newname[NI_MAXHOST];
412 struct addrinfo *addrs;
415 * Attempt to canonicalise addresses, regardless of
416 * whether hostname canonicalisation was requested
418 if ((addrs = resolve_addr(*hostp, port,
419 newname, sizeof(newname))) != NULL) {
420 debug2("%s: hostname %.100s is address", __func__, *hostp);
421 if (strcasecmp(*hostp, newname) != 0) {
422 debug2("%s: canonicalised address \"%s\" => \"%s\"",
423 __func__, *hostp, newname);
425 *hostp = xstrdup(newname);
431 * If this looks like an address but didn't parse as one, it might
432 * be an address with an invalid interface scope. Skip further
433 * attempts at canonicalisation.
435 if (is_addr_fast(*hostp)) {
436 debug("%s: hostname %.100s is an unrecognised address",
441 if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
445 * Don't attempt to canonicalize names that will be interpreted by
446 * a proxy unless the user specifically requests so.
448 direct = option_clear_or_none(options.proxy_command) &&
449 options.jump_host == NULL;
451 options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
454 /* If domain name is anchored, then resolve it now */
455 if ((*hostp)[strlen(*hostp) - 1] == '.') {
456 debug3("%s: name is fully qualified", __func__);
457 fullhost = xstrdup(*hostp);
458 if ((addrs = resolve_host(fullhost, port, 0,
459 newname, sizeof(newname))) != NULL)
465 /* Don't apply canonicalization to sufficiently-qualified hostnames */
467 for (cp = *hostp; *cp != '\0'; cp++) {
471 if (ndots > options.canonicalize_max_dots) {
472 debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)",
473 __func__, *hostp, options.canonicalize_max_dots);
476 /* Attempt each supplied suffix */
477 for (i = 0; i < options.num_canonical_domains; i++) {
479 xasprintf(&fullhost, "%s.%s.", *hostp,
480 options.canonical_domains[i]);
481 debug3("%s: attempting \"%s\" => \"%s\"", __func__,
483 if ((addrs = resolve_host(fullhost, port, 0,
484 newname, sizeof(newname))) == NULL) {
489 /* Remove trailing '.' */
490 fullhost[strlen(fullhost) - 1] = '\0';
491 /* Follow CNAME if requested */
492 if (!check_follow_cname(direct, &fullhost, newname)) {
493 debug("Canonicalized hostname \"%s\" => \"%s\"",
501 if (!options.canonicalize_fallback_local)
502 fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
503 debug2("%s: host %s not found in any suffix", __func__, *hostp);
508 * Read per-user configuration file. Ignore the system wide config
509 * file if the user specifies a config file on the command line.
512 process_config_files(const char *host_name, struct passwd *pw, int post_canon)
517 if (config != NULL) {
518 if (strcasecmp(config, "none") != 0 &&
519 !read_config_file(config, pw, host, host_name, &options,
520 SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0)))
521 fatal("Can't open user config file %.100s: "
522 "%.100s", config, strerror(errno));
524 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
525 _PATH_SSH_USER_CONFFILE);
526 if (r > 0 && (size_t)r < sizeof(buf))
527 (void)read_config_file(buf, pw, host, host_name,
528 &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
529 (post_canon ? SSHCONF_POSTCANON : 0));
531 /* Read systemwide configuration file after user config. */
532 (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
533 host, host_name, &options,
534 post_canon ? SSHCONF_POSTCANON : 0);
538 /* Rewrite the port number in an addrinfo list of addresses */
540 set_addrinfo_port(struct addrinfo *addrs, int port)
542 struct addrinfo *addr;
544 for (addr = addrs; addr != NULL; addr = addr->ai_next) {
545 switch (addr->ai_family) {
547 ((struct sockaddr_in *)addr->ai_addr)->
548 sin_port = htons(port);
551 ((struct sockaddr_in6 *)addr->ai_addr)->
552 sin6_port = htons(port);
559 * Main program for the ssh client.
562 main(int ac, char **av)
564 struct ssh *ssh = NULL;
565 int i, r, opt, exit_status, use_syslog, direct, timeout_ms;
566 int was_addr, config_test = 0, opt_terminated = 0;
567 char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile;
568 char cname[NI_MAXHOST];
571 extern int optind, optreset;
574 struct addrinfo *addrs = NULL;
575 struct ssh_digest_ctx *md;
576 u_char conn_hash[SSH_DIGEST_MAX_LENGTH];
578 ssh_malloc_init(); /* must be called before any mallocs */
579 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
582 __progname = ssh_get_progname(av[0]);
584 #ifndef HAVE_SETPROCTITLE
585 /* Prepare for later setproctitle emulation */
586 /* Save argv so it isn't clobbered by setproctitle() emulation */
587 saved_av = xcalloc(ac + 1, sizeof(*saved_av));
588 for (i = 0; i < ac; i++)
589 saved_av[i] = xstrdup(av[i]);
591 compat_init_setproctitle(ac, av);
596 * Discard other fds that are hanging around. These can cause problem
597 * with backgrounded ssh processes started by ControlPersist.
599 closefrom(STDERR_FILENO + 1);
602 * Save the original real uid. It will be needed later (uid-swapping
603 * may clobber the real uid).
605 original_real_uid = getuid();
606 original_effective_uid = geteuid();
609 * Use uid-swapping to give up root privileges for the duration of
610 * option processing. We will re-instantiate the rights when we are
611 * ready to create the privileged port, and will permanently drop
612 * them when the port has been created (actually, when the connection
613 * has been made, as we may need to create the port several times).
617 #ifdef HAVE_SETRLIMIT
618 /* If we are installed setuid root be careful to not drop core. */
619 if (original_real_uid != original_effective_uid) {
621 rlim.rlim_cur = rlim.rlim_max = 0;
622 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
623 fatal("setrlimit failed: %.100s", strerror(errno));
627 pw = getpwuid(original_real_uid);
629 logit("No user exists for uid %lu", (u_long)original_real_uid);
632 /* Take a copy of the returned structure. */
636 * Set our umask to something reasonable, as some files are created
637 * with the default umask. This will make them world-readable but
638 * writable only by the owner, which is ok for all files for which we
639 * don't set the modes explicitly.
646 * Initialize option structure to indicate that no values have been
649 initialize_options(&options);
652 * Prepare main ssh transport/connection structures
654 if ((ssh = ssh_alloc_session_state()) == NULL)
655 fatal("Couldn't allocate session state");
656 channel_init_channels(ssh);
657 active_state = ssh; /* XXX legacy API compat */
659 /* Parse command-line arguments. */
666 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
667 "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
670 fatal("SSH protocol v.1 is no longer supported");
676 options.address_family = AF_INET;
679 options.address_family = AF_INET6;
685 fork_after_authentication_flag = 1;
689 options.forward_x11 = 0;
692 options.forward_x11 = 1;
704 options.forward_x11 = 1;
705 options.forward_x11_trusted = 1;
708 options.fwd_opts.gateway_ports = 1;
711 if (options.stdio_forward_host != NULL)
712 fatal("Cannot specify multiplexing "
714 else if (muxclient_command != 0)
715 fatal("Multiplexing command already specified");
716 if (strcmp(optarg, "check") == 0)
717 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
718 else if (strcmp(optarg, "forward") == 0)
719 muxclient_command = SSHMUX_COMMAND_FORWARD;
720 else if (strcmp(optarg, "exit") == 0)
721 muxclient_command = SSHMUX_COMMAND_TERMINATE;
722 else if (strcmp(optarg, "stop") == 0)
723 muxclient_command = SSHMUX_COMMAND_STOP;
724 else if (strcmp(optarg, "cancel") == 0)
725 muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
726 else if (strcmp(optarg, "proxy") == 0)
727 muxclient_command = SSHMUX_COMMAND_PROXY;
729 fatal("Invalid multiplex command.");
731 case 'P': /* deprecated */
732 options.use_privileged_port = 0;
736 if (strcmp(optarg, "cipher") == 0)
737 cp = cipher_alg_list('\n', 0);
738 else if (strcmp(optarg, "cipher-auth") == 0)
739 cp = cipher_alg_list('\n', 1);
740 else if (strcmp(optarg, "mac") == 0)
741 cp = mac_alg_list('\n');
742 else if (strcmp(optarg, "kex") == 0)
743 cp = kex_alg_list('\n');
744 else if (strcmp(optarg, "key") == 0)
745 cp = sshkey_alg_list(0, 0, 0, '\n');
746 else if (strcmp(optarg, "key-cert") == 0)
747 cp = sshkey_alg_list(1, 0, 0, '\n');
748 else if (strcmp(optarg, "key-plain") == 0)
749 cp = sshkey_alg_list(0, 1, 0, '\n');
750 else if (strcmp(optarg, "protocol-version") == 0) {
754 fatal("Unsupported query \"%s\"", optarg);
760 options.forward_agent = 0;
763 options.forward_agent = 1;
766 options.gss_deleg_creds = 0;
769 options.gss_authentication = 1;
770 options.gss_deleg_creds = 1;
773 p = tilde_expand_filename(optarg, original_real_uid);
774 if (stat(p, &st) < 0)
775 fprintf(stderr, "Warning: Identity file %s "
776 "not accessible: %s.\n", p,
779 add_identity_file(&options, NULL, p, 1);
784 free(options.pkcs11_provider);
785 options.pkcs11_provider = xstrdup(optarg);
787 fprintf(stderr, "no support for PKCS#11.\n");
791 if (options.jump_host != NULL)
792 fatal("Only a single -J option permitted");
793 if (options.proxy_command != NULL)
794 fatal("Cannot specify -J with ProxyCommand");
795 if (parse_jump(optarg, &options, 1) == -1)
796 fatal("Invalid -J argument");
797 options.proxy_command = xstrdup("none");
800 if (options.request_tty == REQUEST_TTY_YES)
801 options.request_tty = REQUEST_TTY_FORCE;
803 options.request_tty = REQUEST_TTY_YES;
806 if (debug_flag == 0) {
808 options.log_level = SYSLOG_LEVEL_DEBUG1;
810 if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
817 if (options.version_addendum &&
818 *options.version_addendum != '\0')
819 fprintf(stderr, "%s %s, %s\n", SSH_RELEASE,
820 options.version_addendum,
823 fprintf(stderr, "%s, %s\n", SSH_RELEASE,
829 if (options.tun_open == -1)
830 options.tun_open = SSH_TUNMODE_DEFAULT;
831 options.tun_local = a2tun(optarg, &options.tun_remote);
832 if (options.tun_local == SSH_TUNID_ERR) {
834 "Bad tun device '%s'\n", optarg);
839 if (options.stdio_forward_host != NULL)
840 fatal("stdio forward already specified");
841 if (muxclient_command != 0)
842 fatal("Cannot specify stdio forward with -O");
843 if (parse_forward(&fwd, optarg, 1, 0)) {
844 options.stdio_forward_host = fwd.listen_host;
845 options.stdio_forward_port = fwd.listen_port;
846 free(fwd.connect_host);
849 "Bad stdio forwarding specification '%s'\n",
853 options.request_tty = REQUEST_TTY_NO;
857 options.log_level = SYSLOG_LEVEL_QUIET;
860 if (optarg[0] == '^' && optarg[2] == 0 &&
861 (u_char) optarg[1] >= 64 &&
862 (u_char) optarg[1] < 128)
863 options.escape_char = (u_char) optarg[1] & 31;
864 else if (strlen(optarg) == 1)
865 options.escape_char = (u_char) optarg[0];
866 else if (strcmp(optarg, "none") == 0)
867 options.escape_char = SSH_ESCAPECHAR_NONE;
869 fprintf(stderr, "Bad escape character '%s'.\n",
875 if (!ciphers_valid(*optarg == '+' ?
876 optarg + 1 : optarg)) {
877 fprintf(stderr, "Unknown cipher type '%s'\n",
881 free(options.ciphers);
882 options.ciphers = xstrdup(optarg);
885 if (mac_valid(optarg)) {
887 options.macs = xstrdup(optarg);
889 fprintf(stderr, "Unknown mac type '%s'\n",
895 if (options.control_master == SSHCTL_MASTER_YES)
896 options.control_master = SSHCTL_MASTER_ASK;
898 options.control_master = SSHCTL_MASTER_YES;
901 if (options.port == -1) {
902 options.port = a2port(optarg);
903 if (options.port <= 0) {
904 fprintf(stderr, "Bad port '%s'\n",
911 if (options.user == NULL)
912 options.user = optarg;
916 if (parse_forward(&fwd, optarg, 0, 0))
917 add_local_forward(&options, &fwd);
920 "Bad local forwarding specification '%s'\n",
927 if (parse_forward(&fwd, optarg, 0, 1) ||
928 parse_forward(&fwd, optarg, 1, 1)) {
929 add_remote_forward(&options, &fwd);
932 "Bad remote forwarding specification "
939 if (parse_forward(&fwd, optarg, 1, 0)) {
940 add_local_forward(&options, &fwd);
943 "Bad dynamic forwarding specification "
950 options.compression = 1;
954 options.request_tty = REQUEST_TTY_NO;
957 options.request_tty = REQUEST_TTY_NO;
960 line = xstrdup(optarg);
961 if (process_config_line(&options, pw,
962 host ? host : "", host ? host : "", line,
963 "command-line", 0, NULL, SSHCONF_USERCONF) != 0)
971 free(options.control_path);
972 options.control_path = xstrdup(optarg);
975 options.bind_address = optarg;
978 options.bind_interface = optarg;
988 if (optind > 1 && strcmp(av[optind - 1], "--") == 0)
994 if (ac > 0 && !host) {
997 switch (parse_ssh_uri(*av, &tuser, &host, &tport)) {
1002 if (options.user == NULL) {
1003 options.user = tuser;
1007 if (options.port == -1 && tport != -1)
1008 options.port = tport;
1012 cp = strrchr(p, '@');
1016 if (options.user == NULL) {
1027 if (ac > 1 && !opt_terminated) {
1028 optind = optreset = 1;
1034 /* Check that we got a host name. */
1038 host_arg = xstrdup(host);
1041 OpenSSL_add_all_algorithms();
1042 ERR_load_crypto_strings();
1045 /* Initialize the command to execute on remote host. */
1046 buffer_init(&command);
1049 * Save the command to execute on the remote host in a buffer. There
1050 * is no limit on the length of the command, except by the maximum
1051 * packet size. Also sets the tty flag if there is no command.
1054 /* No command specified - execute shell on a tty. */
1055 if (subsystem_flag) {
1057 "You must specify a subsystem to invoke.\n");
1061 /* A command has been specified. Store it into the buffer. */
1062 for (i = 0; i < ac; i++) {
1064 buffer_append(&command, " ", 1);
1065 buffer_append(&command, av[i], strlen(av[i]));
1070 * Initialize "log" output. Since we are the client all output
1071 * goes to stderr unless otherwise specified by -y or -E.
1073 if (use_syslog && logfile != NULL)
1074 fatal("Can't specify both -y and -E");
1075 if (logfile != NULL)
1076 log_redirect_stderr_to(logfile);
1078 options.log_level == SYSLOG_LEVEL_NOT_SET ?
1079 SYSLOG_LEVEL_INFO : options.log_level,
1080 options.log_facility == SYSLOG_FACILITY_NOT_SET ?
1081 SYSLOG_FACILITY_USER : options.log_facility,
1085 /* version_addendum is always NULL at this point */
1086 logit("%s, %s", SSH_RELEASE, OPENSSL_VERSION);
1088 /* Parse the configuration files */
1089 process_config_files(host_arg, pw, 0);
1091 /* Hostname canonicalisation needs a few options filled. */
1092 fill_default_options_for_canonicalization(&options);
1094 /* If the user has replaced the hostname then take it into use now */
1095 if (options.hostname != NULL) {
1096 /* NB. Please keep in sync with readconf.c:match_cfg_line() */
1097 cp = percent_expand(options.hostname,
1098 "h", host, (char *)NULL);
1101 free(options.hostname);
1102 options.hostname = xstrdup(host);
1105 /* Don't lowercase addresses, they will be explicitly canonicalised */
1106 if ((was_addr = is_addr(host)) == 0)
1110 * Try to canonicalize if requested by configuration or the
1111 * hostname is an address.
1113 if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr)
1114 addrs = resolve_canonicalize(&host, options.port);
1117 * If CanonicalizePermittedCNAMEs have been specified but
1118 * other canonicalization did not happen (by not being requested
1119 * or by failing with fallback) then the hostname may still be changed
1120 * as a result of CNAME following.
1122 * Try to resolve the bare hostname name using the system resolver's
1123 * usual search rules and then apply the CNAME follow rules.
1125 * Skip the lookup if a ProxyCommand is being used unless the user
1126 * has specifically requested canonicalisation for this case via
1127 * CanonicalizeHostname=always
1129 direct = option_clear_or_none(options.proxy_command) &&
1130 options.jump_host == NULL;
1131 if (addrs == NULL && options.num_permitted_cnames != 0 && (direct ||
1132 options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
1133 if ((addrs = resolve_host(host, options.port,
1134 option_clear_or_none(options.proxy_command),
1135 cname, sizeof(cname))) == NULL) {
1136 /* Don't fatal proxied host names not in the DNS */
1137 if (option_clear_or_none(options.proxy_command))
1138 cleanup_exit(255); /* logged in resolve_host */
1140 check_follow_cname(direct, &host, cname);
1144 * If canonicalisation is enabled then re-parse the configuration
1145 * files as new stanzas may match.
1147 if (options.canonicalize_hostname != 0) {
1148 debug("Re-reading configuration after hostname "
1149 "canonicalisation");
1150 free(options.hostname);
1151 options.hostname = xstrdup(host);
1152 process_config_files(host_arg, pw, 1);
1154 * Address resolution happens early with canonicalisation
1155 * enabled and the port number may have changed since, so
1156 * reset it in address list
1158 if (addrs != NULL && options.port > 0)
1159 set_addrinfo_port(addrs, options.port);
1162 /* Fill configuration defaults. */
1163 fill_default_options(&options);
1166 * If ProxyJump option specified, then construct a ProxyCommand now.
1168 if (options.jump_host != NULL) {
1171 /* Consistency check */
1172 if (options.proxy_command != NULL)
1173 fatal("inconsistent options: ProxyCommand+ProxyJump");
1174 /* Never use FD passing for ProxyJump */
1175 options.proxy_use_fdpass = 0;
1176 snprintf(port_s, sizeof(port_s), "%d", options.jump_port);
1177 xasprintf(&options.proxy_command,
1178 "ssh%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s",
1179 /* Optional "-l user" argument if jump_user set */
1180 options.jump_user == NULL ? "" : " -l ",
1181 options.jump_user == NULL ? "" : options.jump_user,
1182 /* Optional "-p port" argument if jump_port set */
1183 options.jump_port <= 0 ? "" : " -p ",
1184 options.jump_port <= 0 ? "" : port_s,
1185 /* Optional additional jump hosts ",..." */
1186 options.jump_extra == NULL ? "" : " -J ",
1187 options.jump_extra == NULL ? "" : options.jump_extra,
1188 /* Optional "-F" argumment if -F specified */
1189 config == NULL ? "" : " -F ",
1190 config == NULL ? "" : config,
1191 /* Optional "-v" arguments if -v set */
1192 debug_flag ? " -" : "",
1194 /* Mandatory hostname */
1196 debug("Setting implicit ProxyCommand from ProxyJump: %s",
1197 options.proxy_command);
1200 if (options.port == 0)
1201 options.port = default_ssh_port();
1202 channel_set_af(ssh, options.address_family);
1204 /* Tidy and check options */
1205 if (options.host_key_alias != NULL)
1206 lowercase(options.host_key_alias);
1207 if (options.proxy_command != NULL &&
1208 strcmp(options.proxy_command, "-") == 0 &&
1209 options.proxy_use_fdpass)
1210 fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
1211 if (options.control_persist &&
1212 options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1213 debug("UpdateHostKeys=ask is incompatible with ControlPersist; "
1215 options.update_hostkeys = 0;
1217 if (options.connection_attempts <= 0)
1218 fatal("Invalid number of ConnectionAttempts");
1220 if (original_effective_uid != 0)
1221 options.use_privileged_port = 0;
1224 if (buffer_len(&command) != 0 && options.remote_command != NULL)
1225 fatal("Cannot execute command-line and remote command.");
1227 /* Cannot fork to background if no command. */
1228 if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
1229 options.remote_command == NULL && !no_shell_flag)
1230 fatal("Cannot fork into background without a command "
1234 log_init(argv0, options.log_level, options.log_facility, !use_syslog);
1236 if (options.request_tty == REQUEST_TTY_YES ||
1237 options.request_tty == REQUEST_TTY_FORCE)
1240 /* Allocate a tty by default if no command specified. */
1241 if (buffer_len(&command) == 0 && options.remote_command == NULL)
1242 tty_flag = options.request_tty != REQUEST_TTY_NO;
1245 if (options.request_tty == REQUEST_TTY_NO ||
1246 (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY))
1248 /* Do not allocate a tty if stdin is not a tty. */
1249 if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
1250 options.request_tty != REQUEST_TTY_FORCE) {
1252 logit("Pseudo-terminal will not be allocated because "
1253 "stdin is not a terminal.");
1259 if (options.user == NULL)
1260 options.user = xstrdup(pw->pw_name);
1262 /* Set up strings used to percent_expand() arguments */
1263 if (gethostname(thishost, sizeof(thishost)) == -1)
1264 fatal("gethostname: %s", strerror(errno));
1265 strlcpy(shorthost, thishost, sizeof(shorthost));
1266 shorthost[strcspn(thishost, ".")] = '\0';
1267 snprintf(portstr, sizeof(portstr), "%d", options.port);
1268 snprintf(uidstr, sizeof(uidstr), "%d", pw->pw_uid);
1270 /* Find canonic host name. */
1271 if (strchr(host, '.') == 0) {
1272 struct addrinfo hints;
1273 struct addrinfo *ai = NULL;
1275 memset(&hints, 0, sizeof(hints));
1276 hints.ai_family = options.address_family;
1277 hints.ai_flags = AI_CANONNAME;
1278 hints.ai_socktype = SOCK_STREAM;
1279 errgai = getaddrinfo(host, NULL, &hints, &ai);
1281 if (ai->ai_canonname != NULL)
1282 host = xstrdup(ai->ai_canonname);
1287 if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL ||
1288 ssh_digest_update(md, thishost, strlen(thishost)) < 0 ||
1289 ssh_digest_update(md, host, strlen(host)) < 0 ||
1290 ssh_digest_update(md, portstr, strlen(portstr)) < 0 ||
1291 ssh_digest_update(md, options.user, strlen(options.user)) < 0 ||
1292 ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0)
1293 fatal("%s: mux digest failed", __func__);
1294 ssh_digest_free(md);
1295 conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
1298 * Expand tokens in arguments. NB. LocalCommand is expanded later,
1299 * after port-forwarding is set up, so it may pick up any local
1300 * tunnel interface name allocated.
1302 if (options.remote_command != NULL) {
1303 debug3("expanding RemoteCommand: %s", options.remote_command);
1304 cp = options.remote_command;
1305 options.remote_command = percent_expand(cp,
1316 debug3("expanded RemoteCommand: %s", options.remote_command);
1318 buffer_append(&command, options.remote_command,
1319 strlen(options.remote_command));
1322 if (options.control_path != NULL) {
1323 cp = tilde_expand_filename(options.control_path,
1325 free(options.control_path);
1326 options.control_path = percent_expand(cp,
1339 free(conn_hash_hex);
1342 dump_client_config(&options, host);
1346 if (muxclient_command != 0 && options.control_path == NULL)
1347 fatal("No ControlPath specified for \"-O\" command");
1348 if (options.control_path != NULL) {
1350 if ((sock = muxclient(options.control_path)) >= 0) {
1351 ssh_packet_set_connection(ssh, sock, sock);
1358 * If hostname canonicalisation was not enabled, then we may not
1359 * have yet resolved the hostname. Do so now.
1361 if (addrs == NULL && options.proxy_command == NULL) {
1362 debug2("resolving \"%s\" port %d", host, options.port);
1363 if ((addrs = resolve_host(host, options.port, 1,
1364 cname, sizeof(cname))) == NULL)
1365 cleanup_exit(255); /* resolve_host logs the error */
1368 timeout_ms = options.connection_timeout * 1000;
1370 /* Open a connection to the remote host. */
1371 if (ssh_connect(ssh, host, addrs, &hostaddr, options.port,
1372 options.address_family, options.connection_attempts,
1373 &timeout_ms, options.tcp_keep_alive,
1374 options.use_privileged_port) != 0)
1378 freeaddrinfo(addrs);
1380 packet_set_timeout(options.server_alive_interval,
1381 options.server_alive_count_max);
1383 ssh = active_state; /* XXX */
1386 debug3("timeout: %d ms remain after connect", timeout_ms);
1389 * If we successfully made the connection, load the host private key
1390 * in case we will need it later for combined rsa-rhosts
1391 * authentication. This must be done before releasing extra
1392 * privileges, because the file is only readable by root.
1393 * If we cannot access the private keys, load the public keys
1394 * instead and try to execute the ssh-keysign helper instead.
1396 sensitive_data.nkeys = 0;
1397 sensitive_data.keys = NULL;
1398 sensitive_data.external_keysign = 0;
1399 if (options.hostbased_authentication) {
1400 sensitive_data.nkeys = 11;
1401 sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1402 sizeof(struct sshkey)); /* XXX */
1403 for (i = 0; i < sensitive_data.nkeys; i++)
1404 sensitive_data.keys[i] = NULL;
1407 #ifdef OPENSSL_HAS_ECC
1408 sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA,
1409 _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
1411 sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519,
1412 _PATH_HOST_ED25519_KEY_FILE, "", NULL);
1413 sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1414 _PATH_HOST_RSA_KEY_FILE, "", NULL);
1415 sensitive_data.keys[4] = key_load_private_cert(KEY_DSA,
1416 _PATH_HOST_DSA_KEY_FILE, "", NULL);
1417 #ifdef OPENSSL_HAS_ECC
1418 sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
1419 _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
1421 sensitive_data.keys[6] = key_load_private_type(KEY_ED25519,
1422 _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL);
1423 sensitive_data.keys[7] = key_load_private_type(KEY_RSA,
1424 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1425 sensitive_data.keys[8] = key_load_private_type(KEY_DSA,
1426 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1427 sensitive_data.keys[9] = key_load_private_cert(KEY_XMSS,
1428 _PATH_HOST_XMSS_KEY_FILE, "", NULL);
1429 sensitive_data.keys[10] = key_load_private_type(KEY_XMSS,
1430 _PATH_HOST_XMSS_KEY_FILE, "", NULL, NULL);
1433 if (options.hostbased_authentication == 1 &&
1434 sensitive_data.keys[0] == NULL &&
1435 sensitive_data.keys[5] == NULL &&
1436 sensitive_data.keys[6] == NULL &&
1437 sensitive_data.keys[7] == NULL &&
1438 sensitive_data.keys[8] == NULL &&
1439 sensitive_data.keys[9] == NULL) {
1440 #ifdef OPENSSL_HAS_ECC
1441 sensitive_data.keys[1] = key_load_cert(
1442 _PATH_HOST_ECDSA_KEY_FILE);
1444 sensitive_data.keys[2] = key_load_cert(
1445 _PATH_HOST_ED25519_KEY_FILE);
1446 sensitive_data.keys[3] = key_load_cert(
1447 _PATH_HOST_RSA_KEY_FILE);
1448 sensitive_data.keys[4] = key_load_cert(
1449 _PATH_HOST_DSA_KEY_FILE);
1450 #ifdef OPENSSL_HAS_ECC
1451 sensitive_data.keys[5] = key_load_public(
1452 _PATH_HOST_ECDSA_KEY_FILE, NULL);
1454 sensitive_data.keys[6] = key_load_public(
1455 _PATH_HOST_ED25519_KEY_FILE, NULL);
1456 sensitive_data.keys[7] = key_load_public(
1457 _PATH_HOST_RSA_KEY_FILE, NULL);
1458 sensitive_data.keys[8] = key_load_public(
1459 _PATH_HOST_DSA_KEY_FILE, NULL);
1460 sensitive_data.keys[9] = key_load_cert(
1461 _PATH_HOST_XMSS_KEY_FILE);
1462 sensitive_data.keys[10] = key_load_public(
1463 _PATH_HOST_XMSS_KEY_FILE, NULL);
1464 sensitive_data.external_keysign = 1;
1468 * Get rid of any extra privileges that we may have. We will no
1469 * longer need them. Also, extra privileges could make it very hard
1470 * to read identity files and other non-world-readable files from the
1471 * user's home directory if it happens to be on a NFS volume where
1472 * root is mapped to nobody.
1474 if (original_effective_uid == 0) {
1476 permanently_set_uid(pw);
1480 * Now that we are back to our own permissions, create ~/.ssh
1481 * directory if it doesn't already exist.
1483 if (config == NULL) {
1484 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1485 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1486 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) {
1488 ssh_selinux_setfscreatecon(buf);
1490 if (mkdir(buf, 0700) < 0)
1491 error("Could not create directory '%.200s'.",
1494 ssh_selinux_setfscreatecon(NULL);
1498 /* load options.identity_files */
1499 load_public_identity_files(pw);
1501 /* optionally set the SSH_AUTHSOCKET_ENV_NAME varibale */
1502 if (options.identity_agent &&
1503 strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) {
1504 if (strcmp(options.identity_agent, "none") == 0) {
1505 unsetenv(SSH_AUTHSOCKET_ENV_NAME);
1507 p = tilde_expand_filename(options.identity_agent,
1509 cp = percent_expand(p, "d", pw->pw_dir,
1510 "u", pw->pw_name, "l", thishost, "h", host,
1511 "r", options.user, (char *)NULL);
1512 setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1);
1518 /* Expand ~ in known host file names. */
1519 tilde_expand_paths(options.system_hostfiles,
1520 options.num_system_hostfiles);
1521 tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1523 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1524 signal(SIGCHLD, main_sigchld_handler);
1526 /* Log into the remote system. Never returns if the login fails. */
1527 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1528 options.port, pw, timeout_ms);
1530 if (packet_connection_is_on_socket()) {
1531 verbose("Authenticated to %s ([%s]:%d).", host,
1532 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1534 verbose("Authenticated to %s (via proxy).", host);
1537 /* We no longer need the private host keys. Clear them now. */
1538 if (sensitive_data.nkeys != 0) {
1539 for (i = 0; i < sensitive_data.nkeys; i++) {
1540 if (sensitive_data.keys[i] != NULL) {
1541 /* Destroys contents safely */
1542 debug3("clear hostkey %d", i);
1543 key_free(sensitive_data.keys[i]);
1544 sensitive_data.keys[i] = NULL;
1547 free(sensitive_data.keys);
1549 for (i = 0; i < options.num_identity_files; i++) {
1550 free(options.identity_files[i]);
1551 options.identity_files[i] = NULL;
1552 if (options.identity_keys[i]) {
1553 key_free(options.identity_keys[i]);
1554 options.identity_keys[i] = NULL;
1557 for (i = 0; i < options.num_certificate_files; i++) {
1558 free(options.certificate_files[i]);
1559 options.certificate_files[i] = NULL;
1563 exit_status = ssh_session2(ssh, pw);
1566 if (options.control_path != NULL && muxserver_sock != -1)
1567 unlink(options.control_path);
1569 /* Kill ProxyCommand if it is running. */
1570 ssh_kill_proxy_command();
1576 control_persist_detach(void)
1579 int devnull, keep_stderr;
1581 debug("%s: backgrounding master process", __func__);
1584 * master (current process) into the background, and make the
1585 * foreground process a client of the backgrounded master.
1587 switch ((pid = fork())) {
1589 fatal("%s: fork: %s", __func__, strerror(errno));
1591 /* Child: master process continues mainloop */
1594 /* Parent: set up mux slave to connect to backgrounded master */
1595 debug2("%s: background process is %ld", __func__, (long)pid);
1596 stdin_null_flag = ostdin_null_flag;
1597 options.request_tty = orequest_tty;
1598 tty_flag = otty_flag;
1599 close(muxserver_sock);
1600 muxserver_sock = -1;
1601 options.control_master = SSHCTL_MASTER_NO;
1602 muxclient(options.control_path);
1603 /* muxclient() doesn't return on success. */
1604 fatal("Failed to connect to new control master");
1606 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1607 error("%s: open(\"/dev/null\"): %s", __func__,
1610 keep_stderr = log_is_on_stderr() && debug_flag;
1611 if (dup2(devnull, STDIN_FILENO) == -1 ||
1612 dup2(devnull, STDOUT_FILENO) == -1 ||
1613 (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1))
1614 error("%s: dup2: %s", __func__, strerror(errno));
1615 if (devnull > STDERR_FILENO)
1619 setproctitle("%s [mux]", options.control_path);
1622 /* Do fork() after authentication. Used by "ssh -f" */
1626 if (need_controlpersist_detach)
1627 control_persist_detach();
1628 debug("forking to background");
1629 fork_after_authentication_flag = 0;
1630 if (daemon(1, 1) < 0)
1631 fatal("daemon() failed: %.200s", strerror(errno));
1634 /* Callback for remote forward global requests */
1636 ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt)
1638 struct Forward *rfwd = (struct Forward *)ctxt;
1640 /* XXX verbose() on failure? */
1641 debug("remote forward %s for: listen %s%s%d, connect %s:%d",
1642 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1643 rfwd->listen_path ? rfwd->listen_path :
1644 rfwd->listen_host ? rfwd->listen_host : "",
1645 (rfwd->listen_path || rfwd->listen_host) ? ":" : "",
1646 rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
1647 rfwd->connect_host, rfwd->connect_port);
1648 if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
1649 if (type == SSH2_MSG_REQUEST_SUCCESS) {
1650 rfwd->allocated_port = packet_get_int();
1651 logit("Allocated port %u for remote forward to %s:%d",
1652 rfwd->allocated_port,
1653 rfwd->connect_host, rfwd->connect_port);
1654 channel_update_permitted_opens(ssh,
1655 rfwd->handle, rfwd->allocated_port);
1657 channel_update_permitted_opens(ssh, rfwd->handle, -1);
1661 if (type == SSH2_MSG_REQUEST_FAILURE) {
1662 if (options.exit_on_forward_failure) {
1663 if (rfwd->listen_path != NULL)
1664 fatal("Error: remote port forwarding failed "
1665 "for listen path %s", rfwd->listen_path);
1667 fatal("Error: remote port forwarding failed "
1668 "for listen port %d", rfwd->listen_port);
1670 if (rfwd->listen_path != NULL)
1671 logit("Warning: remote port forwarding failed "
1672 "for listen path %s", rfwd->listen_path);
1674 logit("Warning: remote port forwarding failed "
1675 "for listen port %d", rfwd->listen_port);
1678 if (++remote_forward_confirms_received == options.num_remote_forwards) {
1679 debug("All remote forwarding requests processed");
1680 if (fork_after_authentication_flag)
1686 client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg)
1688 debug("stdio forwarding: done");
1693 ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg)
1696 fatal("stdio forwarding failed");
1700 ssh_init_stdio_forwarding(struct ssh *ssh)
1705 if (options.stdio_forward_host == NULL)
1708 debug3("%s: %s:%d", __func__, options.stdio_forward_host,
1709 options.stdio_forward_port);
1711 if ((in = dup(STDIN_FILENO)) < 0 ||
1712 (out = dup(STDOUT_FILENO)) < 0)
1713 fatal("channel_connect_stdio_fwd: dup() in/out failed");
1714 if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host,
1715 options.stdio_forward_port, in, out)) == NULL)
1716 fatal("%s: channel_connect_stdio_fwd failed", __func__);
1717 channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0);
1718 channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL);
1722 ssh_init_forwarding(struct ssh *ssh, char **ifname)
1727 /* Initiate local TCP/IP port forwardings. */
1728 for (i = 0; i < options.num_local_forwards; i++) {
1729 debug("Local connections to %.200s:%d forwarded to remote "
1730 "address %.200s:%d",
1731 (options.local_forwards[i].listen_path != NULL) ?
1732 options.local_forwards[i].listen_path :
1733 (options.local_forwards[i].listen_host == NULL) ?
1734 (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
1735 options.local_forwards[i].listen_host,
1736 options.local_forwards[i].listen_port,
1737 (options.local_forwards[i].connect_path != NULL) ?
1738 options.local_forwards[i].connect_path :
1739 options.local_forwards[i].connect_host,
1740 options.local_forwards[i].connect_port);
1741 success += channel_setup_local_fwd_listener(ssh,
1742 &options.local_forwards[i], &options.fwd_opts);
1744 if (i > 0 && success != i && options.exit_on_forward_failure)
1745 fatal("Could not request local forwarding.");
1746 if (i > 0 && success == 0)
1747 error("Could not request local forwarding.");
1749 /* Initiate remote TCP/IP port forwardings. */
1750 for (i = 0; i < options.num_remote_forwards; i++) {
1751 debug("Remote connections from %.200s:%d forwarded to "
1752 "local address %.200s:%d",
1753 (options.remote_forwards[i].listen_path != NULL) ?
1754 options.remote_forwards[i].listen_path :
1755 (options.remote_forwards[i].listen_host == NULL) ?
1756 "LOCALHOST" : options.remote_forwards[i].listen_host,
1757 options.remote_forwards[i].listen_port,
1758 (options.remote_forwards[i].connect_path != NULL) ?
1759 options.remote_forwards[i].connect_path :
1760 options.remote_forwards[i].connect_host,
1761 options.remote_forwards[i].connect_port);
1762 options.remote_forwards[i].handle =
1763 channel_request_remote_forwarding(ssh,
1764 &options.remote_forwards[i]);
1765 if (options.remote_forwards[i].handle < 0) {
1766 if (options.exit_on_forward_failure)
1767 fatal("Could not request remote forwarding.");
1769 logit("Warning: Could not request remote "
1772 client_register_global_confirm(
1773 ssh_confirm_remote_forward,
1774 &options.remote_forwards[i]);
1778 /* Initiate tunnel forwarding. */
1779 if (options.tun_open != SSH_TUNMODE_NO) {
1780 if ((*ifname = client_request_tun_fwd(ssh,
1781 options.tun_open, options.tun_local,
1782 options.tun_remote)) == NULL) {
1783 if (options.exit_on_forward_failure)
1784 fatal("Could not request tunnel forwarding.");
1786 error("Could not request tunnel forwarding.");
1792 check_agent_present(void)
1796 if (options.forward_agent) {
1797 /* Clear agent forwarding if we don't have an agent. */
1798 if ((r = ssh_get_authentication_socket(NULL)) != 0) {
1799 options.forward_agent = 0;
1800 if (r != SSH_ERR_AGENT_NOT_PRESENT)
1801 debug("ssh_get_authentication_socket: %s",
1808 ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg)
1810 extern char **environ;
1811 const char *display;
1812 int interactive = tty_flag;
1813 char *proto = NULL, *data = NULL;
1816 return; /* No need for error message, channels code sens one */
1818 display = getenv("DISPLAY");
1819 if (display == NULL && options.forward_x11)
1820 debug("X11 forwarding requested but DISPLAY not set");
1821 if (options.forward_x11 && client_x11_get_proto(ssh, display,
1822 options.xauth_location, options.forward_x11_trusted,
1823 options.forward_x11_timeout, &proto, &data) == 0) {
1824 /* Request forwarding with authentication spoofing. */
1825 debug("Requesting X11 forwarding with authentication "
1827 x11_request_forwarding_with_spoofing(ssh, id, display, proto,
1829 client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN);
1830 /* XXX exit_on_forward_failure */
1834 check_agent_present();
1835 if (options.forward_agent) {
1836 debug("Requesting authentication agent forwarding.");
1837 channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0);
1841 /* Tell the packet module whether this is an interactive session. */
1842 packet_set_interactive(interactive,
1843 options.ip_qos_interactive, options.ip_qos_bulk);
1845 client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"),
1846 NULL, fileno(stdin), &command, environ);
1849 /* open new channel for a session */
1851 ssh_session2_open(struct ssh *ssh)
1854 int window, packetmax, in, out, err;
1856 if (stdin_null_flag) {
1857 in = open(_PATH_DEVNULL, O_RDONLY);
1859 in = dup(STDIN_FILENO);
1861 out = dup(STDOUT_FILENO);
1862 err = dup(STDERR_FILENO);
1864 if (in < 0 || out < 0 || err < 0)
1865 fatal("dup() in/out/err failed");
1867 /* enable nonblocking unless tty */
1875 window = CHAN_SES_WINDOW_DEFAULT;
1876 packetmax = CHAN_SES_PACKET_DEFAULT;
1881 c = channel_new(ssh,
1882 "session", SSH_CHANNEL_OPENING, in, out, err,
1883 window, packetmax, CHAN_EXTENDED_WRITE,
1884 "client-session", /*nonblock*/0);
1886 debug3("%s: channel_new: %d", __func__, c->self);
1888 channel_send_open(ssh, c->self);
1890 channel_register_open_confirm(ssh, c->self,
1891 ssh_session2_setup, NULL);
1897 ssh_session2(struct ssh *ssh, struct passwd *pw)
1899 int devnull, id = -1;
1900 char *cp, *tun_fwd_ifname = NULL;
1902 /* XXX should be pre-session */
1903 if (!options.control_persist)
1904 ssh_init_stdio_forwarding(ssh);
1906 ssh_init_forwarding(ssh, &tun_fwd_ifname);
1908 if (options.local_command != NULL) {
1909 debug3("expanding LocalCommand: %s", options.local_command);
1910 cp = options.local_command;
1911 options.local_command = percent_expand(cp,
1921 "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname,
1923 debug3("expanded LocalCommand: %s", options.local_command);
1927 /* Start listening for multiplex clients */
1928 if (!packet_get_mux())
1929 muxserver_listen(ssh);
1932 * If we are in control persist mode and have a working mux listen
1933 * socket, then prepare to background ourselves and have a foreground
1934 * client attach as a control slave.
1935 * NB. we must save copies of the flags that we override for
1936 * the backgrounding, since we defer attachment of the slave until
1937 * after the connection is fully established (in particular,
1938 * async rfwd replies have been received for ExitOnForwardFailure).
1940 if (options.control_persist && muxserver_sock != -1) {
1941 ostdin_null_flag = stdin_null_flag;
1942 ono_shell_flag = no_shell_flag;
1943 orequest_tty = options.request_tty;
1944 otty_flag = tty_flag;
1945 stdin_null_flag = 1;
1948 if (!fork_after_authentication_flag)
1949 need_controlpersist_detach = 1;
1950 fork_after_authentication_flag = 1;
1953 * ControlPersist mux listen socket setup failed, attempt the
1954 * stdio forward setup that we skipped earlier.
1956 if (options.control_persist && muxserver_sock == -1)
1957 ssh_init_stdio_forwarding(ssh);
1960 id = ssh_session2_open(ssh);
1962 packet_set_interactive(
1963 options.control_master == SSHCTL_MASTER_NO,
1964 options.ip_qos_interactive, options.ip_qos_bulk);
1967 /* If we don't expect to open a new session, then disallow it */
1968 if (options.control_master == SSHCTL_MASTER_NO &&
1969 (datafellows & SSH_NEW_OPENSSH)) {
1970 debug("Requesting no-more-sessions@openssh.com");
1971 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1972 packet_put_cstring("no-more-sessions@openssh.com");
1977 /* Execute a local command */
1978 if (options.local_command != NULL &&
1979 options.permit_local_command)
1980 ssh_local_cmd(options.local_command);
1983 * stdout is now owned by the session channel; clobber it here
1984 * so future channel closes are propagated to the local fd.
1985 * NB. this can only happen after LocalCommand has completed,
1986 * as it may want to write to stdout.
1988 if (!need_controlpersist_detach) {
1989 if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1)
1990 error("%s: open %s: %s", __func__,
1991 _PATH_DEVNULL, strerror(errno));
1992 if (dup2(devnull, STDOUT_FILENO) < 0)
1993 fatal("%s: dup2() stdout failed", __func__);
1994 if (devnull > STDERR_FILENO)
1999 * If requested and we are not interested in replies to remote
2000 * forwarding requests, then let ssh continue in the background.
2002 if (fork_after_authentication_flag) {
2003 if (options.exit_on_forward_failure &&
2004 options.num_remote_forwards > 0) {
2005 debug("deferring postauth fork until remote forward "
2006 "confirmation received");
2011 return client_loop(ssh, tty_flag, tty_flag ?
2012 options.escape_char : SSH_ESCAPECHAR_NONE, id);
2015 /* Loads all IdentityFile and CertificateFile keys */
2017 load_public_identity_files(struct passwd *pw)
2019 char *filename, *cp;
2020 struct sshkey *public;
2022 u_int n_ids, n_certs;
2023 char *identity_files[SSH_MAX_IDENTITY_FILES];
2024 struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
2025 char *certificate_files[SSH_MAX_CERTIFICATE_FILES];
2026 struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
2027 #ifdef ENABLE_PKCS11
2028 struct sshkey **keys;
2032 n_ids = n_certs = 0;
2033 memset(identity_files, 0, sizeof(identity_files));
2034 memset(identity_keys, 0, sizeof(identity_keys));
2035 memset(certificate_files, 0, sizeof(certificate_files));
2036 memset(certificates, 0, sizeof(certificates));
2038 #ifdef ENABLE_PKCS11
2039 if (options.pkcs11_provider != NULL &&
2040 options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
2041 (pkcs11_init(!options.batch_mode) == 0) &&
2042 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
2044 for (i = 0; i < nkeys; i++) {
2045 if (n_ids >= SSH_MAX_IDENTITY_FILES) {
2049 identity_keys[n_ids] = keys[i];
2050 identity_files[n_ids] =
2051 xstrdup(options.pkcs11_provider); /* XXX */
2056 #endif /* ENABLE_PKCS11 */
2057 if ((pw = getpwuid(original_real_uid)) == NULL)
2058 fatal("load_public_identity_files: getpwuid failed");
2059 for (i = 0; i < options.num_identity_files; i++) {
2060 if (n_ids >= SSH_MAX_IDENTITY_FILES ||
2061 strcasecmp(options.identity_files[i], "none") == 0) {
2062 free(options.identity_files[i]);
2063 options.identity_files[i] = NULL;
2066 cp = tilde_expand_filename(options.identity_files[i],
2068 filename = percent_expand(cp, "d", pw->pw_dir,
2069 "u", pw->pw_name, "l", thishost, "h", host,
2070 "r", options.user, (char *)NULL);
2072 public = key_load_public(filename, NULL);
2073 debug("identity file %s type %d", filename,
2074 public ? public->type : -1);
2075 free(options.identity_files[i]);
2076 identity_files[n_ids] = filename;
2077 identity_keys[n_ids] = public;
2079 if (++n_ids >= SSH_MAX_IDENTITY_FILES)
2083 * If no certificates have been explicitly listed then try
2084 * to add the default certificate variant too.
2086 if (options.num_certificate_files != 0)
2088 xasprintf(&cp, "%s-cert", filename);
2089 public = key_load_public(cp, NULL);
2090 debug("identity file %s type %d", cp,
2091 public ? public->type : -1);
2092 if (public == NULL) {
2096 if (!key_is_cert(public)) {
2097 debug("%s: key %s type %s is not a certificate",
2098 __func__, cp, key_type(public));
2103 /* NB. leave filename pointing to private key */
2104 identity_files[n_ids] = xstrdup(filename);
2105 identity_keys[n_ids] = public;
2109 if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES)
2110 fatal("%s: too many certificates", __func__);
2111 for (i = 0; i < options.num_certificate_files; i++) {
2112 cp = tilde_expand_filename(options.certificate_files[i],
2114 filename = percent_expand(cp, "d", pw->pw_dir,
2115 "u", pw->pw_name, "l", thishost, "h", host,
2116 "r", options.user, (char *)NULL);
2119 public = key_load_public(filename, NULL);
2120 debug("certificate file %s type %d", filename,
2121 public ? public->type : -1);
2122 free(options.certificate_files[i]);
2123 options.certificate_files[i] = NULL;
2124 if (public == NULL) {
2128 if (!key_is_cert(public)) {
2129 debug("%s: key %s type %s is not a certificate",
2130 __func__, filename, key_type(public));
2135 certificate_files[n_certs] = filename;
2136 certificates[n_certs] = public;
2140 options.num_identity_files = n_ids;
2141 memcpy(options.identity_files, identity_files, sizeof(identity_files));
2142 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
2144 options.num_certificate_files = n_certs;
2145 memcpy(options.certificate_files,
2146 certificate_files, sizeof(certificate_files));
2147 memcpy(options.certificates, certificates, sizeof(certificates));
2151 main_sigchld_handler(int sig)
2153 int save_errno = errno;
2157 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
2158 (pid < 0 && errno == EINTR))