1 /* $OpenBSD: sshconnect.c,v 1.355 2021/07/02 05:11:21 dtucker Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * Code to connect to a remote host, and to perform the client side of the
7 * login (authentication) dialog.
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
19 #include <sys/types.h>
22 #include <sys/socket.h>
23 #ifdef HAVE_SYS_TIME_H
24 # include <sys/time.h>
28 #include <netinet/in.h>
29 #include <arpa/inet.h>
60 #include "sshconnect.h"
66 #include "monitor_fdpass.h"
74 struct sshkey *previous_host_key = NULL;
76 static int matching_host_key_dns = 0;
78 static pid_t proxy_command_pid = 0;
81 extern int debug_flag;
82 extern Options options;
83 extern char *__progname;
85 static int show_other_keys(struct hostkeys *, struct sshkey *);
86 static void warn_changed_key(struct sshkey *);
88 /* Expand a proxy command */
90 expand_proxy_command(const char *proxy_command, const char *user,
91 const char *host, const char *host_arg, int port)
93 char *tmp, *ret, strport[NI_MAXSERV];
94 const char *keyalias = options.host_key_alias ?
95 options.host_key_alias : host_arg;
97 snprintf(strport, sizeof strport, "%d", port);
98 xasprintf(&tmp, "exec %s", proxy_command);
99 ret = percent_expand(tmp,
111 * Connect to the given ssh server using a proxy command that passes a
112 * a connected fd back to us.
115 ssh_proxy_fdpass_connect(struct ssh *ssh, const char *host,
116 const char *host_arg, u_short port, const char *proxy_command)
118 char *command_string;
123 if ((shell = getenv("SHELL")) == NULL)
124 shell = _PATH_BSHELL;
126 if (socketpair(AF_UNIX, SOCK_STREAM, 0, sp) == -1)
127 fatal("Could not create socketpair to communicate with "
128 "proxy dialer: %.100s", strerror(errno));
130 command_string = expand_proxy_command(proxy_command, options.user,
131 host, host_arg, port);
132 debug("Executing proxy dialer command: %.500s", command_string);
134 /* Fork and execute the proxy command. */
135 if ((pid = fork()) == 0) {
139 /* Redirect stdin and stdout. */
141 if (dup2(sp[0], 0) == -1)
142 perror("dup2 stdin");
145 if (dup2(sp[0], 1) == -1)
146 perror("dup2 stdout");
152 * Stderr is left for non-ControlPersist connections is so
153 * error messages may be printed on the user's terminal.
155 if (!debug_flag && options.control_path != NULL &&
156 options.control_persist && stdfd_devnull(0, 0, 1) == -1)
157 error_f("stdfd_devnull failed");
161 argv[2] = command_string;
165 * Execute the proxy command.
166 * Note that we gave up any extra privileges above.
168 execv(argv[0], argv);
174 fatal("fork failed: %.100s", strerror(errno));
176 free(command_string);
178 if ((sock = mm_receive_fd(sp[1])) == -1)
179 fatal("proxy dialer did not pass back a connection");
182 while (waitpid(pid, NULL, 0) == -1)
184 fatal("Couldn't wait for child: %s", strerror(errno));
186 /* Set the connection file descriptors. */
187 if (ssh_packet_set_connection(ssh, sock, sock) == NULL)
188 return -1; /* ssh_packet_set_connection logs error */
194 * Connect to the given ssh server using a proxy command.
197 ssh_proxy_connect(struct ssh *ssh, const char *host, const char *host_arg,
198 u_short port, const char *proxy_command)
200 char *command_string;
205 if ((shell = getenv("SHELL")) == NULL || *shell == '\0')
206 shell = _PATH_BSHELL;
208 /* Create pipes for communicating with the proxy. */
209 if (pipe(pin) == -1 || pipe(pout) == -1)
210 fatal("Could not create pipes to communicate with the proxy: %.100s",
213 command_string = expand_proxy_command(proxy_command, options.user,
214 host, host_arg, port);
215 debug("Executing proxy command: %.500s", command_string);
217 /* Fork and execute the proxy command. */
218 if ((pid = fork()) == 0) {
221 /* Redirect stdin and stdout. */
224 if (dup2(pin[0], 0) == -1)
225 perror("dup2 stdin");
229 if (dup2(pout[1], 1) == -1)
230 perror("dup2 stdout");
231 /* Cannot be 1 because pin allocated two descriptors. */
235 * Stderr is left for non-ControlPersist connections is so
236 * error messages may be printed on the user's terminal.
238 if (!debug_flag && options.control_path != NULL &&
239 options.control_persist && stdfd_devnull(0, 0, 1) == -1)
240 error_f("stdfd_devnull failed");
244 argv[2] = command_string;
248 * Execute the proxy command. Note that we gave up any
249 * extra privileges above.
251 ssh_signal(SIGPIPE, SIG_DFL);
252 execv(argv[0], argv);
258 fatal("fork failed: %.100s", strerror(errno));
260 proxy_command_pid = pid; /* save pid to clean up later */
262 /* Close child side of the descriptors. */
266 /* Free the command name. */
267 free(command_string);
269 /* Set the connection file descriptors. */
270 if (ssh_packet_set_connection(ssh, pout[0], pin[1]) == NULL)
271 return -1; /* ssh_packet_set_connection logs error */
277 ssh_kill_proxy_command(void)
280 * Send SIGHUP to proxy command if used. We don't wait() in
281 * case it hangs and instead rely on init to reap the child
283 if (proxy_command_pid > 1)
284 kill(proxy_command_pid, SIGHUP);
287 #ifdef HAVE_IFADDRS_H
289 * Search a interface address list (returned from getifaddrs(3)) for an
290 * address that matches the desired address family on the specified interface.
291 * Returns 0 and fills in *resultp and *rlenp on success. Returns -1 on failure.
294 check_ifaddrs(const char *ifname, int af, const struct ifaddrs *ifaddrs,
295 struct sockaddr_storage *resultp, socklen_t *rlenp)
297 struct sockaddr_in6 *sa6;
298 struct sockaddr_in *sa;
299 struct in6_addr *v6addr;
300 const struct ifaddrs *ifa;
304 * Prefer addresses that are not loopback or linklocal, but use them
305 * if nothing else matches.
307 for (allow_local = 0; allow_local < 2; allow_local++) {
308 for (ifa = ifaddrs; ifa != NULL; ifa = ifa->ifa_next) {
309 if (ifa->ifa_addr == NULL || ifa->ifa_name == NULL ||
310 (ifa->ifa_flags & IFF_UP) == 0 ||
311 ifa->ifa_addr->sa_family != af ||
312 strcmp(ifa->ifa_name, options.bind_interface) != 0)
314 switch (ifa->ifa_addr->sa_family) {
316 sa = (struct sockaddr_in *)ifa->ifa_addr;
317 if (!allow_local && sa->sin_addr.s_addr ==
318 htonl(INADDR_LOOPBACK))
320 if (*rlenp < sizeof(struct sockaddr_in)) {
321 error_f("v4 addr doesn't fit");
324 *rlenp = sizeof(struct sockaddr_in);
325 memcpy(resultp, sa, *rlenp);
328 sa6 = (struct sockaddr_in6 *)ifa->ifa_addr;
329 v6addr = &sa6->sin6_addr;
331 (IN6_IS_ADDR_LINKLOCAL(v6addr) ||
332 IN6_IS_ADDR_LOOPBACK(v6addr)))
334 if (*rlenp < sizeof(struct sockaddr_in6)) {
335 error_f("v6 addr doesn't fit");
338 *rlenp = sizeof(struct sockaddr_in6);
339 memcpy(resultp, sa6, *rlenp);
349 * Creates a socket for use as the ssh connection.
352 ssh_create_socket(struct addrinfo *ai)
355 struct sockaddr_storage bindaddr;
356 socklen_t bindaddrlen = 0;
357 struct addrinfo hints, *res = NULL;
358 #ifdef HAVE_IFADDRS_H
359 struct ifaddrs *ifaddrs = NULL;
361 char ntop[NI_MAXHOST];
363 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
365 error("socket: %s", strerror(errno));
368 fcntl(sock, F_SETFD, FD_CLOEXEC);
370 /* Use interactive QOS (if specified) until authentication completed */
371 if (options.ip_qos_interactive != INT_MAX)
372 set_sock_tos(sock, options.ip_qos_interactive);
374 /* Bind the socket to an alternative local IP address */
375 if (options.bind_address == NULL && options.bind_interface == NULL)
378 if (options.bind_address != NULL) {
379 memset(&hints, 0, sizeof(hints));
380 hints.ai_family = ai->ai_family;
381 hints.ai_socktype = ai->ai_socktype;
382 hints.ai_protocol = ai->ai_protocol;
383 hints.ai_flags = AI_PASSIVE;
384 if ((r = getaddrinfo(options.bind_address, NULL,
385 &hints, &res)) != 0) {
386 error("getaddrinfo: %s: %s", options.bind_address,
387 ssh_gai_strerror(r));
391 error("getaddrinfo: no addrs");
394 memcpy(&bindaddr, res->ai_addr, res->ai_addrlen);
395 bindaddrlen = res->ai_addrlen;
396 } else if (options.bind_interface != NULL) {
397 #ifdef HAVE_IFADDRS_H
398 if ((r = getifaddrs(&ifaddrs)) != 0) {
399 error("getifaddrs: %s: %s", options.bind_interface,
403 bindaddrlen = sizeof(bindaddr);
404 if (check_ifaddrs(options.bind_interface, ai->ai_family,
405 ifaddrs, &bindaddr, &bindaddrlen) != 0) {
406 logit("getifaddrs: %s: no suitable addresses",
407 options.bind_interface);
411 error("BindInterface not supported on this platform.");
414 if ((r = getnameinfo((struct sockaddr *)&bindaddr, bindaddrlen,
415 ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST)) != 0) {
416 error_f("getnameinfo failed: %s", ssh_gai_strerror(r));
419 if (bind(sock, (struct sockaddr *)&bindaddr, bindaddrlen) != 0) {
420 error("bind %s: %s", ntop, strerror(errno));
423 debug_f("bound to %s", ntop);
432 #ifdef HAVE_IFADDRS_H
434 freeifaddrs(ifaddrs);
440 * Opens a TCP/IP connection to the remote server on the given host.
441 * The address of the remote host will be returned in hostaddr.
442 * If port is 0, the default port will be used.
443 * Connection_attempts specifies the maximum number of tries (one per
444 * second). If proxy_command is non-NULL, it specifies the command (with %h
445 * and %p substituted for host and port, respectively) to use to contact
449 ssh_connect_direct(struct ssh *ssh, const char *host, struct addrinfo *aitop,
450 struct sockaddr_storage *hostaddr, u_short port, int connection_attempts,
451 int *timeout_ms, int want_keepalive)
453 int on = 1, saved_timeout_ms = *timeout_ms;
454 int oerrno, sock = -1, attempt;
455 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
458 debug3_f("entering");
459 memset(ntop, 0, sizeof(ntop));
460 memset(strport, 0, sizeof(strport));
462 for (attempt = 0; attempt < connection_attempts; attempt++) {
464 /* Sleep a moment before retrying. */
466 debug("Trying again...");
469 * Loop through addresses for this host, and try each one in
470 * sequence until the connection succeeds.
472 for (ai = aitop; ai; ai = ai->ai_next) {
473 if (ai->ai_family != AF_INET &&
474 ai->ai_family != AF_INET6) {
475 errno = EAFNOSUPPORT;
478 if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
479 ntop, sizeof(ntop), strport, sizeof(strport),
480 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
482 error_f("getnameinfo failed");
486 debug("Connecting to %.200s [%.100s] port %s.",
487 host, ntop, strport);
489 /* Create a socket for connecting. */
490 sock = ssh_create_socket(ai);
492 /* Any error is already output */
497 *timeout_ms = saved_timeout_ms;
498 if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
500 /* Successful connection. */
501 memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
505 debug("connect to address %s port %s: %s",
506 ntop, strport, strerror(errno));
513 break; /* Successful connection. */
516 /* Return failure if we didn't get a successful connection. */
518 error("ssh: connect to host %s port %s: %s",
519 host, strport, errno == 0 ? "failure" : strerror(errno));
523 debug("Connection established.");
525 /* Set SO_KEEPALIVE if requested. */
526 if (want_keepalive &&
527 setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
529 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
531 /* Set the connection. */
532 if (ssh_packet_set_connection(ssh, sock, sock) == NULL)
533 return -1; /* ssh_packet_set_connection logs error */
539 ssh_connect(struct ssh *ssh, const char *host, const char *host_arg,
540 struct addrinfo *addrs, struct sockaddr_storage *hostaddr, u_short port,
541 int connection_attempts, int *timeout_ms, int want_keepalive)
545 if (options.proxy_command == NULL) {
546 return ssh_connect_direct(ssh, host, addrs, hostaddr, port,
547 connection_attempts, timeout_ms, want_keepalive);
548 } else if (strcmp(options.proxy_command, "-") == 0) {
549 if ((in = dup(STDIN_FILENO)) == -1 ||
550 (out = dup(STDOUT_FILENO)) == -1) {
553 error_f("dup() in/out failed");
554 return -1; /* ssh_packet_set_connection logs error */
556 if ((ssh_packet_set_connection(ssh, in, out)) == NULL)
557 return -1; /* ssh_packet_set_connection logs error */
559 } else if (options.proxy_use_fdpass) {
560 return ssh_proxy_fdpass_connect(ssh, host, host_arg, port,
561 options.proxy_command);
563 return ssh_proxy_connect(ssh, host, host_arg, port,
564 options.proxy_command);
567 /* defaults to 'no' */
569 confirm(const char *prompt, const char *fingerprint)
571 const char *msg, *again = "Please type 'yes' or 'no': ";
572 const char *again_fp = "Please type 'yes', 'no' or the fingerprint: ";
576 if (options.batch_mode)
578 for (msg = prompt;;msg = fingerprint ? again_fp : again) {
579 cp = p = read_passphrase(msg, RP_ECHO);
582 p += strspn(p, " \t"); /* skip leading whitespace */
583 p[strcspn(p, " \t\n")] = '\0'; /* remove trailing whitespace */
584 if (p[0] == '\0' || strcasecmp(p, "no") == 0)
586 else if (strcasecmp(p, "yes") == 0 || (fingerprint != NULL &&
587 strcmp(p, fingerprint) == 0))
596 sockaddr_is_local(struct sockaddr *hostaddr)
598 switch (hostaddr->sa_family) {
600 return (ntohl(((struct sockaddr_in *)hostaddr)->
601 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
603 return IN6_IS_ADDR_LOOPBACK(
604 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
611 * Prepare the hostname and ip address strings that are used to lookup
612 * host keys in known_hosts files. These may have a port number appended.
615 get_hostfile_hostname_ipaddr(char *hostname, struct sockaddr *hostaddr,
616 u_short port, char **hostfile_hostname, char **hostfile_ipaddr)
618 char ntop[NI_MAXHOST];
621 switch (hostaddr == NULL ? -1 : hostaddr->sa_family) {
626 addrlen = sizeof(struct sockaddr_in);
629 addrlen = sizeof(struct sockaddr_in6);
632 addrlen = sizeof(struct sockaddr);
637 * We don't have the remote ip-address for connections
638 * using a proxy command
640 if (hostfile_ipaddr != NULL) {
641 if (options.proxy_command == NULL) {
642 if (getnameinfo(hostaddr, addrlen,
643 ntop, sizeof(ntop), NULL, 0, NI_NUMERICHOST) != 0)
644 fatal_f("getnameinfo failed");
645 *hostfile_ipaddr = put_host_port(ntop, port);
647 *hostfile_ipaddr = xstrdup("<no hostip for proxy "
653 * Allow the user to record the key under a different name or
654 * differentiate a non-standard port. This is useful for ssh
655 * tunneling over forwarded connections or if you run multiple
656 * sshd's on different ports on the same machine.
658 if (hostfile_hostname != NULL) {
659 if (options.host_key_alias != NULL) {
660 *hostfile_hostname = xstrdup(options.host_key_alias);
661 debug("using hostkeyalias: %s", *hostfile_hostname);
663 *hostfile_hostname = put_host_port(hostname, port);
668 /* returns non-zero if path appears in hostfiles, or 0 if not. */
670 path_in_hostfiles(const char *path, char **hostfiles, u_int num_hostfiles)
674 for (i = 0; i < num_hostfiles; i++) {
675 if (strcmp(path, hostfiles[i]) == 0)
681 struct find_by_key_ctx {
682 const char *host, *ip;
683 const struct sshkey *key;
688 /* Try to replace home directory prefix (per $HOME) with a ~/ sequence */
690 try_tilde_unexpand(const char *path)
692 char *home, *ret = NULL;
696 return xstrdup(path);
697 if ((home = getenv("HOME")) == NULL || (l = strlen(home)) == 0)
698 return xstrdup(path);
699 if (strncmp(path, home, l) != 0)
700 return xstrdup(path);
702 * ensure we have matched on a path boundary: either the $HOME that
703 * we just compared ends with a '/' or the next character of the path
706 if (home[l - 1] != '/' && path[l] != '/')
707 return xstrdup(path);
710 xasprintf(&ret, "~/%s", path + l);
715 hostkeys_find_by_key_cb(struct hostkey_foreach_line *l, void *_ctx)
717 struct find_by_key_ctx *ctx = (struct find_by_key_ctx *)_ctx;
720 /* we are looking for keys with names that *do not* match */
721 if ((l->match & HKF_MATCH_HOST) != 0)
723 /* not interested in marker lines */
724 if (l->marker != MRK_NONE)
726 /* we are only interested in exact key matches */
727 if (l->key == NULL || !sshkey_equal(ctx->key, l->key))
729 path = try_tilde_unexpand(l->path);
730 debug_f("found matching key in %s:%lu", path, l->linenum);
731 ctx->names = xrecallocarray(ctx->names,
732 ctx->nnames, ctx->nnames + 1, sizeof(*ctx->names));
733 xasprintf(&ctx->names[ctx->nnames], "%s:%lu: %s", path, l->linenum,
734 strncmp(l->hosts, HASH_MAGIC, strlen(HASH_MAGIC)) == 0 ?
735 "[hashed name]" : l->hosts);
742 hostkeys_find_by_key_hostfile(const char *file, const char *which,
743 struct find_by_key_ctx *ctx)
747 debug3_f("trying %s hostfile \"%s\"", which, file);
748 if ((r = hostkeys_foreach(file, hostkeys_find_by_key_cb, ctx,
749 ctx->host, ctx->ip, HKF_WANT_PARSE_KEY, 0)) != 0) {
750 if (r == SSH_ERR_SYSTEM_ERROR && errno == ENOENT) {
751 debug_f("hostkeys file %s does not exist", file);
754 error_fr(r, "hostkeys_foreach failed for %s", file);
761 * Find 'key' in known hosts file(s) that do not match host/ip.
762 * Used to display also-known-as information for previously-unseen hostkeys.
765 hostkeys_find_by_key(const char *host, const char *ip, const struct sshkey *key,
766 char **user_hostfiles, u_int num_user_hostfiles,
767 char **system_hostfiles, u_int num_system_hostfiles,
768 char ***names, u_int *nnames)
770 struct find_by_key_ctx ctx = {0, 0, 0, 0, 0};
776 if (key == NULL || sshkey_is_cert(key))
783 for (i = 0; i < num_user_hostfiles; i++) {
784 if (hostkeys_find_by_key_hostfile(user_hostfiles[i],
788 for (i = 0; i < num_system_hostfiles; i++) {
789 if (hostkeys_find_by_key_hostfile(system_hostfiles[i],
790 "system", &ctx) != 0)
795 *nnames = ctx.nnames;
800 for (i = 0; i < ctx.nnames; i++)
805 #define MAX_OTHER_NAMES 8 /* Maximum number of names to list */
807 other_hostkeys_message(const char *host, const char *ip,
808 const struct sshkey *key,
809 char **user_hostfiles, u_int num_user_hostfiles,
810 char **system_hostfiles, u_int num_system_hostfiles)
812 char *ret = NULL, **othernames = NULL;
813 u_int i, n, num_othernames = 0;
815 hostkeys_find_by_key(host, ip, key,
816 user_hostfiles, num_user_hostfiles,
817 system_hostfiles, num_system_hostfiles,
818 &othernames, &num_othernames);
819 if (num_othernames == 0)
820 return xstrdup("This key is not known by any other names");
822 xasprintf(&ret, "This host key is known by the following other "
826 if (n > MAX_OTHER_NAMES)
828 for (i = 0; i < n; i++) {
829 xextendf(&ret, "\n", " %s", othernames[i]);
831 if (n < num_othernames) {
832 xextendf(&ret, "\n", " (%d additional names omitted)",
835 for (i = 0; i < num_othernames; i++)
842 load_hostkeys_command(struct hostkeys *hostkeys, const char *command_template,
843 const char *invocation, const struct ssh_conn_info *cinfo,
844 const struct sshkey *host_key, const char *hostfile_hostname)
847 char *key_fp = NULL, *keytext = NULL, *tmp;
848 char *command = NULL, *tag = NULL, **av = NULL;
851 void (*osigchld)(int);
853 xasprintf(&tag, "KnownHostsCommand-%s", invocation);
855 if (host_key != NULL) {
856 if ((key_fp = sshkey_fingerprint(host_key,
857 options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
858 fatal_f("sshkey_fingerprint failed");
859 if ((r = sshkey_to_base64(host_key, &keytext)) != 0)
860 fatal_fr(r, "sshkey_to_base64 failed");
863 * NB. all returns later this function should go via "out" to
864 * ensure the original SIGCHLD handler is restored properly.
866 osigchld = ssh_signal(SIGCHLD, SIG_DFL);
868 /* Turn the command into an argument vector */
869 if (argv_split(command_template, &ac, &av, 0) != 0) {
870 error("%s \"%s\" contains invalid quotes", tag,
875 error("%s \"%s\" yielded no arguments", tag,
879 for (i = 1; i < ac; i++) {
880 tmp = percent_dollar_expand(av[i],
881 DEFAULT_CLIENT_PERCENT_EXPAND_ARGS(cinfo),
882 "H", hostfile_hostname,
884 "t", host_key == NULL ? "NONE" : sshkey_ssh_name(host_key),
885 "f", key_fp == NULL ? "NONE" : key_fp,
886 "K", keytext == NULL ? "NONE" : keytext,
889 fatal_f("percent_expand failed");
893 /* Prepare a printable command for logs, etc. */
894 command = argv_assemble(ac, av);
896 if ((pid = subprocess(tag, command, ac, av, &f,
897 SSH_SUBPROCESS_STDOUT_CAPTURE|SSH_SUBPROCESS_UNSAFE_PATH|
898 SSH_SUBPROCESS_PRESERVE_ENV, NULL, NULL, NULL)) == 0)
901 load_hostkeys_file(hostkeys, hostfile_hostname, tag, f, 1);
903 if (exited_cleanly(pid, tag, command, 0) != 0)
904 fatal("KnownHostsCommand failed");
909 ssh_signal(SIGCHLD, osigchld);
910 for (i = 0; i < ac; i++)
920 * check whether the supplied host key is valid, return -1 if the key
921 * is not valid. user_hostfile[0] will not be updated if 'readonly' is true.
927 check_host_key(char *hostname, const struct ssh_conn_info *cinfo,
928 struct sockaddr *hostaddr, u_short port,
929 struct sshkey *host_key, int readonly, int clobber_port,
930 char **user_hostfiles, u_int num_user_hostfiles,
931 char **system_hostfiles, u_int num_system_hostfiles,
932 const char *hostfile_command)
934 HostStatus host_status = -1, ip_status = -1;
935 struct sshkey *raw_key = NULL;
936 char *ip = NULL, *host = NULL;
937 char hostline[1000], *hostp, *fp, *ra;
939 const char *type, *fail_reason;
940 const struct hostkey_entry *host_found = NULL, *ip_found = NULL;
941 int len, cancelled_forwarding = 0, confirmed;
942 int local = sockaddr_is_local(hostaddr);
943 int r, want_cert = sshkey_is_cert(host_key), host_ip_differ = 0;
944 int hostkey_trusted = 0; /* Known or explicitly accepted by user */
945 struct hostkeys *host_hostkeys, *ip_hostkeys;
949 * Force accepting of the host key for loopback/localhost. The
950 * problem is that if the home directory is NFS-mounted to multiple
951 * machines, localhost will refer to a different machine in each of
952 * them, and the user will get bogus HOST_CHANGED warnings. This
953 * essentially disables host authentication for localhost; however,
954 * this is probably not a real problem.
956 if (options.no_host_authentication_for_localhost == 1 && local &&
957 options.host_key_alias == NULL) {
958 debug("Forcing accepting of host key for "
959 "loopback/localhost.");
960 options.update_hostkeys = 0;
965 * Prepare the hostname and address strings used for hostkey lookup.
966 * In some cases, these will have a port number appended.
968 get_hostfile_hostname_ipaddr(hostname, hostaddr,
969 clobber_port ? 0 : port, &host, &ip);
972 * Turn off check_host_ip if the connection is to localhost, via proxy
973 * command or if we don't have a hostname to compare with
975 if (options.check_host_ip && (local ||
976 strcmp(hostname, ip) == 0 || options.proxy_command != NULL))
977 options.check_host_ip = 0;
979 host_hostkeys = init_hostkeys();
980 for (i = 0; i < num_user_hostfiles; i++)
981 load_hostkeys(host_hostkeys, host, user_hostfiles[i], 0);
982 for (i = 0; i < num_system_hostfiles; i++)
983 load_hostkeys(host_hostkeys, host, system_hostfiles[i], 0);
984 if (hostfile_command != NULL && !clobber_port) {
985 load_hostkeys_command(host_hostkeys, hostfile_command,
986 "HOSTNAME", cinfo, host_key, host);
990 if (!want_cert && options.check_host_ip) {
991 ip_hostkeys = init_hostkeys();
992 for (i = 0; i < num_user_hostfiles; i++)
993 load_hostkeys(ip_hostkeys, ip, user_hostfiles[i], 0);
994 for (i = 0; i < num_system_hostfiles; i++)
995 load_hostkeys(ip_hostkeys, ip, system_hostfiles[i], 0);
996 if (hostfile_command != NULL && !clobber_port) {
997 load_hostkeys_command(ip_hostkeys, hostfile_command,
998 "ADDRESS", cinfo, host_key, ip);
1003 /* Reload these as they may have changed on cert->key downgrade */
1004 want_cert = sshkey_is_cert(host_key);
1005 type = sshkey_type(host_key);
1008 * Check if the host key is present in the user's list of known
1009 * hosts or in the systemwide list.
1011 host_status = check_key_in_hostkeys(host_hostkeys, host_key,
1015 * If there are no hostfiles, or if the hostkey was found via
1016 * KnownHostsCommand, then don't try to touch the disk.
1018 if (!readonly && (num_user_hostfiles == 0 ||
1019 (host_found != NULL && host_found->note != 0)))
1023 * Also perform check for the ip address, skip the check if we are
1024 * localhost, looking for a certificate, or the hostname was an ip
1025 * address to begin with.
1027 if (!want_cert && ip_hostkeys != NULL) {
1028 ip_status = check_key_in_hostkeys(ip_hostkeys, host_key,
1030 if (host_status == HOST_CHANGED &&
1031 (ip_status != HOST_CHANGED ||
1032 (ip_found != NULL &&
1033 !sshkey_equal(ip_found->key, host_found->key))))
1036 ip_status = host_status;
1038 switch (host_status) {
1040 /* The host is known and the key matches. */
1041 debug("Host '%.200s' is known and matches the %s host %s.",
1042 host, type, want_cert ? "certificate" : "key");
1043 debug("Found %s in %s:%lu", want_cert ? "CA key" : "key",
1044 host_found->file, host_found->line);
1046 if (sshkey_cert_check_host(host_key,
1047 options.host_key_alias == NULL ?
1048 hostname : options.host_key_alias, 0,
1049 options.ca_sign_algorithms, &fail_reason) != 0) {
1050 error("%s", fail_reason);
1054 * Do not attempt hostkey update if a certificate was
1055 * successfully matched.
1057 if (options.update_hostkeys != 0) {
1058 options.update_hostkeys = 0;
1059 debug3_f("certificate host key in use; "
1060 "disabling UpdateHostkeys");
1063 /* Turn off UpdateHostkeys if key was in system known_hosts */
1064 if (options.update_hostkeys != 0 &&
1065 (path_in_hostfiles(host_found->file,
1066 system_hostfiles, num_system_hostfiles) ||
1067 (ip_status == HOST_OK && ip_found != NULL &&
1068 path_in_hostfiles(ip_found->file,
1069 system_hostfiles, num_system_hostfiles)))) {
1070 options.update_hostkeys = 0;
1071 debug3_f("host key found in GlobalKnownHostsFile; "
1072 "disabling UpdateHostkeys");
1074 if (options.update_hostkeys != 0 && host_found->note) {
1075 options.update_hostkeys = 0;
1076 debug3_f("host key found via KnownHostsCommand; "
1077 "disabling UpdateHostkeys");
1079 if (options.check_host_ip && ip_status == HOST_NEW) {
1080 if (readonly || want_cert)
1081 logit("%s host key for IP address "
1082 "'%.128s' not in list of known hosts.",
1084 else if (!add_host_to_hostfile(user_hostfiles[0], ip,
1085 host_key, options.hash_known_hosts))
1086 logit("Failed to add the %s host key for IP "
1087 "address '%.128s' to the list of known "
1088 "hosts (%.500s).", type, ip,
1091 logit("Warning: Permanently added the %s host "
1092 "key for IP address '%.128s' to the list "
1093 "of known hosts.", type, ip);
1094 } else if (options.visual_host_key) {
1095 fp = sshkey_fingerprint(host_key,
1096 options.fingerprint_hash, SSH_FP_DEFAULT);
1097 ra = sshkey_fingerprint(host_key,
1098 options.fingerprint_hash, SSH_FP_RANDOMART);
1099 if (fp == NULL || ra == NULL)
1100 fatal_f("sshkey_fingerprint failed");
1101 logit("Host key fingerprint is %s\n%s", fp, ra);
1105 hostkey_trusted = 1;
1108 if (options.host_key_alias == NULL && port != 0 &&
1109 port != SSH_DEFAULT_PORT && !clobber_port) {
1110 debug("checking without port identifier");
1111 if (check_host_key(hostname, cinfo, hostaddr, 0,
1112 host_key, ROQUIET, 1,
1113 user_hostfiles, num_user_hostfiles,
1114 system_hostfiles, num_system_hostfiles,
1115 hostfile_command) == 0) {
1116 debug("found matching key w/out port");
1120 if (readonly || want_cert)
1122 /* The host is new. */
1123 if (options.strict_host_key_checking ==
1124 SSH_STRICT_HOSTKEY_YES) {
1126 * User has requested strict host key checking. We
1127 * will not add the host key automatically. The only
1128 * alternative left is to abort.
1130 error("No %s host key is known for %.200s and you "
1131 "have requested strict checking.", type, host);
1133 } else if (options.strict_host_key_checking ==
1134 SSH_STRICT_HOSTKEY_ASK) {
1135 char *msg1 = NULL, *msg2 = NULL;
1137 xasprintf(&msg1, "The authenticity of host "
1138 "'%.200s (%s)' can't be established", host, ip);
1140 if (show_other_keys(host_hostkeys, host_key)) {
1141 xextendf(&msg1, "\n", "but keys of different "
1142 "type are already known for this host.");
1144 xextendf(&msg1, "", ".");
1146 fp = sshkey_fingerprint(host_key,
1147 options.fingerprint_hash, SSH_FP_DEFAULT);
1148 ra = sshkey_fingerprint(host_key,
1149 options.fingerprint_hash, SSH_FP_RANDOMART);
1150 if (fp == NULL || ra == NULL)
1151 fatal_f("sshkey_fingerprint failed");
1152 xextendf(&msg1, "\n", "%s key fingerprint is %s.",
1154 if (options.visual_host_key)
1155 xextendf(&msg1, "\n", "%s", ra);
1156 if (options.verify_host_key_dns) {
1157 xextendf(&msg1, "\n",
1158 "%s host key fingerprint found in DNS.",
1159 matching_host_key_dns ?
1160 "Matching" : "No matching");
1162 /* msg2 informs for other names matching this key */
1163 if ((msg2 = other_hostkeys_message(host, ip, host_key,
1164 user_hostfiles, num_user_hostfiles,
1165 system_hostfiles, num_system_hostfiles)) != NULL)
1166 xextendf(&msg1, "\n", "%s", msg2);
1168 xextendf(&msg1, "\n",
1169 "Are you sure you want to continue connecting "
1170 "(yes/no/[fingerprint])? ");
1172 confirmed = confirm(msg1, fp);
1179 hostkey_trusted = 1; /* user explicitly confirmed */
1182 * If in "new" or "off" strict mode, add the key automatically
1183 * to the local known_hosts file.
1185 if (options.check_host_ip && ip_status == HOST_NEW) {
1186 snprintf(hostline, sizeof(hostline), "%s,%s", host, ip);
1188 if (options.hash_known_hosts) {
1189 /* Add hash of host and IP separately */
1190 r = add_host_to_hostfile(user_hostfiles[0],
1191 host, host_key, options.hash_known_hosts) &&
1192 add_host_to_hostfile(user_hostfiles[0], ip,
1193 host_key, options.hash_known_hosts);
1195 /* Add unhashed "host,ip" */
1196 r = add_host_to_hostfile(user_hostfiles[0],
1198 options.hash_known_hosts);
1201 r = add_host_to_hostfile(user_hostfiles[0], host,
1202 host_key, options.hash_known_hosts);
1207 logit("Failed to add the host to the list of known "
1208 "hosts (%.500s).", user_hostfiles[0]);
1210 logit("Warning: Permanently added '%.200s' (%s) to the "
1211 "list of known hosts.", hostp, type);
1214 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1215 error("@ WARNING: REVOKED HOST KEY DETECTED! @");
1216 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1217 error("The %s host key for %s is marked as revoked.", type, host);
1218 error("This could mean that a stolen key is being used to");
1219 error("impersonate this host.");
1222 * If strict host key checking is in use, the user will have
1223 * to edit the key manually and we can only abort.
1225 if (options.strict_host_key_checking !=
1226 SSH_STRICT_HOSTKEY_OFF) {
1227 error("%s host key for %.200s was revoked and you have "
1228 "requested strict checking.", type, host);
1231 goto continue_unsafe;
1236 * This is only a debug() since it is valid to have
1237 * CAs with wildcard DNS matches that don't match
1238 * all hosts that one might visit.
1240 debug("Host certificate authority does not "
1241 "match %s in %s:%lu", CA_MARKER,
1242 host_found->file, host_found->line);
1245 if (readonly == ROQUIET)
1247 if (options.check_host_ip && host_ip_differ) {
1249 if (ip_status == HOST_NEW)
1250 key_msg = "is unknown";
1251 else if (ip_status == HOST_OK)
1252 key_msg = "is unchanged";
1254 key_msg = "has a different value";
1255 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1256 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
1257 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1258 error("The %s host key for %s has changed,", type, host);
1259 error("and the key for the corresponding IP address %s", ip);
1260 error("%s. This could either mean that", key_msg);
1261 error("DNS SPOOFING is happening or the IP address for the host");
1262 error("and its host key have changed at the same time.");
1263 if (ip_status != HOST_NEW)
1264 error("Offending key for IP in %s:%lu",
1265 ip_found->file, ip_found->line);
1267 /* The host key has changed. */
1268 warn_changed_key(host_key);
1269 error("Add correct host key in %.100s to get rid of this message.",
1271 error("Offending %s key in %s:%lu",
1272 sshkey_type(host_found->key),
1273 host_found->file, host_found->line);
1276 * If strict host key checking is in use, the user will have
1277 * to edit the key manually and we can only abort.
1279 if (options.strict_host_key_checking !=
1280 SSH_STRICT_HOSTKEY_OFF) {
1281 error("Host key for %.200s has changed and you have "
1282 "requested strict checking.", host);
1288 * If strict host key checking has not been requested, allow
1289 * the connection but without MITM-able authentication or
1292 if (options.password_authentication) {
1293 error("Password authentication is disabled to avoid "
1294 "man-in-the-middle attacks.");
1295 options.password_authentication = 0;
1296 cancelled_forwarding = 1;
1298 if (options.kbd_interactive_authentication) {
1299 error("Keyboard-interactive authentication is disabled"
1300 " to avoid man-in-the-middle attacks.");
1301 options.kbd_interactive_authentication = 0;
1302 cancelled_forwarding = 1;
1304 if (options.forward_agent) {
1305 error("Agent forwarding is disabled to avoid "
1306 "man-in-the-middle attacks.");
1307 options.forward_agent = 0;
1308 cancelled_forwarding = 1;
1310 if (options.forward_x11) {
1311 error("X11 forwarding is disabled to avoid "
1312 "man-in-the-middle attacks.");
1313 options.forward_x11 = 0;
1314 cancelled_forwarding = 1;
1316 if (options.num_local_forwards > 0 ||
1317 options.num_remote_forwards > 0) {
1318 error("Port forwarding is disabled to avoid "
1319 "man-in-the-middle attacks.");
1320 options.num_local_forwards =
1321 options.num_remote_forwards = 0;
1322 cancelled_forwarding = 1;
1324 if (options.tun_open != SSH_TUNMODE_NO) {
1325 error("Tunnel forwarding is disabled to avoid "
1326 "man-in-the-middle attacks.");
1327 options.tun_open = SSH_TUNMODE_NO;
1328 cancelled_forwarding = 1;
1330 if (options.update_hostkeys != 0) {
1331 error("UpdateHostkeys is disabled because the host "
1332 "key is not trusted.");
1333 options.update_hostkeys = 0;
1335 if (options.exit_on_forward_failure && cancelled_forwarding)
1336 fatal("Error: forwarding disabled due to host key "
1340 * XXX Should permit the user to change to use the new id.
1341 * This could be done by converting the host key to an
1342 * identifying sentence, tell that the host identifies itself
1343 * by that sentence, and ask the user if they wish to
1344 * accept the authentication.
1348 fatal("internal error");
1352 if (options.check_host_ip && host_status != HOST_CHANGED &&
1353 ip_status == HOST_CHANGED) {
1354 snprintf(msg, sizeof(msg),
1355 "Warning: the %s host key for '%.200s' "
1356 "differs from the key for the IP address '%.128s'"
1357 "\nOffending key for IP in %s:%lu",
1358 type, host, ip, ip_found->file, ip_found->line);
1359 if (host_status == HOST_OK) {
1361 snprintf(msg + len, sizeof(msg) - len,
1362 "\nMatching host key in %s:%lu",
1363 host_found->file, host_found->line);
1365 if (options.strict_host_key_checking ==
1366 SSH_STRICT_HOSTKEY_ASK) {
1367 strlcat(msg, "\nAre you sure you want "
1368 "to continue connecting (yes/no)? ", sizeof(msg));
1369 if (!confirm(msg, NULL))
1371 } else if (options.strict_host_key_checking !=
1372 SSH_STRICT_HOSTKEY_OFF) {
1374 error("Exiting, you have requested strict checking.");
1381 if (!hostkey_trusted && options.update_hostkeys) {
1382 debug_f("hostkey not known or explicitly trusted: "
1383 "disabling UpdateHostkeys");
1384 options.update_hostkeys = 0;
1389 if (host_hostkeys != NULL)
1390 free_hostkeys(host_hostkeys);
1391 if (ip_hostkeys != NULL)
1392 free_hostkeys(ip_hostkeys);
1396 if (want_cert && host_status != HOST_REVOKED) {
1398 * No matching certificate. Downgrade cert to raw key and
1401 debug("No matching CA found. Retry with plain key");
1402 if ((r = sshkey_from_private(host_key, &raw_key)) != 0)
1403 fatal_fr(r, "decode key");
1404 if ((r = sshkey_drop_cert(raw_key)) != 0)
1405 fatal_r(r, "Couldn't drop certificate");
1409 sshkey_free(raw_key);
1412 if (host_hostkeys != NULL)
1413 free_hostkeys(host_hostkeys);
1414 if (ip_hostkeys != NULL)
1415 free_hostkeys(ip_hostkeys);
1419 /* returns 0 if key verifies or -1 if key does NOT verify */
1421 verify_host_key(char *host, struct sockaddr *hostaddr, struct sshkey *host_key,
1422 const struct ssh_conn_info *cinfo)
1425 int r = -1, flags = 0;
1426 char valid[64], *fp = NULL, *cafp = NULL;
1427 struct sshkey *plain = NULL;
1429 if ((fp = sshkey_fingerprint(host_key,
1430 options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
1431 error_fr(r, "fingerprint host key");
1436 if (sshkey_is_cert(host_key)) {
1437 if ((cafp = sshkey_fingerprint(host_key->cert->signature_key,
1438 options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL) {
1439 error_fr(r, "fingerprint CA key");
1443 sshkey_format_cert_validity(host_key->cert,
1444 valid, sizeof(valid));
1445 debug("Server host certificate: %s %s, serial %llu "
1446 "ID \"%s\" CA %s %s valid %s",
1447 sshkey_ssh_name(host_key), fp,
1448 (unsigned long long)host_key->cert->serial,
1449 host_key->cert->key_id,
1450 sshkey_ssh_name(host_key->cert->signature_key), cafp,
1452 for (i = 0; i < host_key->cert->nprincipals; i++) {
1453 debug2("Server host certificate hostname: %s",
1454 host_key->cert->principals[i]);
1457 debug("Server host key: %s %s", sshkey_ssh_name(host_key), fp);
1460 if (sshkey_equal(previous_host_key, host_key)) {
1461 debug2_f("server host key %s %s matches cached key",
1462 sshkey_type(host_key), fp);
1467 /* Check in RevokedHostKeys file if specified */
1468 if (options.revoked_host_keys != NULL) {
1469 r = sshkey_check_revoked(host_key, options.revoked_host_keys);
1472 break; /* not revoked */
1473 case SSH_ERR_KEY_REVOKED:
1474 error("Host key %s %s revoked by file %s",
1475 sshkey_type(host_key), fp,
1476 options.revoked_host_keys);
1480 error_r(r, "Error checking host key %s %s in "
1481 "revoked keys file %s", sshkey_type(host_key),
1482 fp, options.revoked_host_keys);
1488 if (options.verify_host_key_dns) {
1490 * XXX certs are not yet supported for DNS, so downgrade
1491 * them and try the plain key.
1493 if ((r = sshkey_from_private(host_key, &plain)) != 0)
1495 if (sshkey_is_cert(plain))
1496 sshkey_drop_cert(plain);
1497 if (verify_host_key_dns(host, hostaddr, plain, &flags) == 0) {
1498 if (flags & DNS_VERIFY_FOUND) {
1499 if (options.verify_host_key_dns == 1 &&
1500 flags & DNS_VERIFY_MATCH &&
1501 flags & DNS_VERIFY_SECURE) {
1505 if (flags & DNS_VERIFY_MATCH) {
1506 matching_host_key_dns = 1;
1508 warn_changed_key(plain);
1509 error("Update the SSHFP RR in DNS "
1510 "with the new host key to get rid "
1511 "of this message.");
1516 r = check_host_key(host, cinfo, hostaddr, options.port, host_key,
1517 RDRW, 0, options.user_hostfiles, options.num_user_hostfiles,
1518 options.system_hostfiles, options.num_system_hostfiles,
1519 options.known_hosts_command);
1525 if (r == 0 && host_key != NULL) {
1526 sshkey_free(previous_host_key);
1527 r = sshkey_from_private(host_key, &previous_host_key);
1534 * Starts a dialog with the server, and authenticates the current user on the
1535 * server. This does not need any extra privileges. The basic connection
1536 * to the server must already have been established before this is called.
1537 * If login fails, this function prints an error and never returns.
1538 * This function does not require super-user privileges.
1541 ssh_login(struct ssh *ssh, Sensitive *sensitive, const char *orighost,
1542 struct sockaddr *hostaddr, u_short port, struct passwd *pw, int timeout_ms,
1543 const struct ssh_conn_info *cinfo)
1546 char *server_user, *local_user;
1549 local_user = xstrdup(pw->pw_name);
1550 server_user = options.user ? options.user : local_user;
1552 /* Convert the user-supplied hostname into all lowercase. */
1553 host = xstrdup(orighost);
1556 /* Exchange protocol version identification strings with the server. */
1557 if ((r = kex_exchange_identification(ssh, timeout_ms,
1558 options.version_addendum)) != 0)
1559 sshpkt_fatal(ssh, r, "banner exchange");
1561 /* Put the connection into non-blocking mode. */
1562 ssh_packet_set_nonblocking(ssh);
1565 /* authenticate user */
1566 debug("Authenticating to %s:%d as '%s'", host, port, server_user);
1567 ssh_kex2(ssh, host, hostaddr, port, cinfo);
1568 ssh_userauth2(ssh, local_user, server_user, host, sensitive);
1573 /* print all known host keys for a given host, but skip keys of given type */
1575 show_other_keys(struct hostkeys *hostkeys, struct sshkey *key)
1587 const struct hostkey_entry *found;
1589 for (i = 0; type[i] != -1; i++) {
1590 if (type[i] == key->type)
1592 if (!lookup_key_in_hostkeys_by_type(hostkeys, type[i],
1595 fp = sshkey_fingerprint(found->key,
1596 options.fingerprint_hash, SSH_FP_DEFAULT);
1597 ra = sshkey_fingerprint(found->key,
1598 options.fingerprint_hash, SSH_FP_RANDOMART);
1599 if (fp == NULL || ra == NULL)
1600 fatal_f("sshkey_fingerprint fail");
1601 logit("WARNING: %s key found for host %s\n"
1603 "%s key fingerprint %s.",
1604 sshkey_type(found->key),
1605 found->host, found->file, found->line,
1606 sshkey_type(found->key), fp);
1607 if (options.visual_host_key)
1617 warn_changed_key(struct sshkey *host_key)
1621 fp = sshkey_fingerprint(host_key, options.fingerprint_hash,
1624 fatal_f("sshkey_fingerprint fail");
1626 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1627 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
1628 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1629 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
1630 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
1631 error("It is also possible that a host key has just been changed.");
1632 error("The fingerprint for the %s key sent by the remote host is\n%s.",
1633 sshkey_type(host_key), fp);
1634 error("Please contact your system administrator.");
1640 * Execute a local command
1643 ssh_local_cmd(const char *args)
1648 void (*osighand)(int);
1650 if (!options.permit_local_command ||
1651 args == NULL || !*args)
1654 if ((shell = getenv("SHELL")) == NULL || *shell == '\0')
1655 shell = _PATH_BSHELL;
1657 osighand = ssh_signal(SIGCHLD, SIG_DFL);
1660 ssh_signal(SIGPIPE, SIG_DFL);
1661 debug3("Executing %s -c \"%s\"", shell, args);
1662 execl(shell, shell, "-c", args, (char *)NULL);
1663 error("Couldn't execute %s -c \"%s\": %s",
1664 shell, args, strerror(errno));
1666 } else if (pid == -1)
1667 fatal("fork failed: %.100s", strerror(errno));
1668 while (waitpid(pid, &status, 0) == -1)
1670 fatal("Couldn't wait for child: %s", strerror(errno));
1671 ssh_signal(SIGCHLD, osighand);
1673 if (!WIFEXITED(status))
1676 return (WEXITSTATUS(status));
1680 maybe_add_key_to_agent(const char *authfile, struct sshkey *private,
1681 const char *comment, const char *passphrase)
1683 int auth_sock = -1, r;
1684 const char *skprovider = NULL;
1686 if (options.add_keys_to_agent == 0)
1689 if ((r = ssh_get_authentication_socket(&auth_sock)) != 0) {
1690 debug3("no authentication agent, not adding key");
1694 if (options.add_keys_to_agent == 2 &&
1695 !ask_permission("Add key %s (%s) to agent?", authfile, comment)) {
1696 debug3("user denied adding this key");
1700 if (sshkey_is_sk(private))
1701 skprovider = options.sk_provider;
1702 if ((r = ssh_add_identity_constrained(auth_sock, private,
1703 comment == NULL ? authfile : comment,
1704 options.add_keys_to_agent_lifespan,
1705 (options.add_keys_to_agent == 3), 0, skprovider)) == 0)
1706 debug("identity added to agent: %s", authfile);
1708 debug("could not add identity to agent: %s (%d)", authfile, r);