1 /* $OpenBSD: sshconnect.c,v 1.181 2006/04/20 09:47:59 markus 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".
18 #include <sys/types.h>
35 #include "sshconnect.h"
43 char *client_version_string = NULL;
44 char *server_version_string = NULL;
46 static int matching_host_key_dns = 0;
49 extern Options options;
50 extern char *__progname;
51 extern uid_t original_real_uid;
52 extern uid_t original_effective_uid;
53 extern pid_t proxy_command_pid;
55 #ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */
56 #define INET6_ADDRSTRLEN 46
59 static int show_other_keys(const char *, Key *);
60 static void warn_changed_key(Key *);
63 * Connect to the given ssh server using a proxy command.
66 ssh_proxy_connect(const char *host, u_short port, const char *proxy_command)
68 char *command_string, *tmp;
71 char strport[NI_MAXSERV];
73 /* Convert the port number into a string. */
74 snprintf(strport, sizeof strport, "%hu", port);
77 * Build the final command string in the buffer by making the
78 * appropriate substitutions to the given proxy command.
80 * Use "exec" to avoid "sh -c" processes on some platforms
83 xasprintf(&tmp, "exec %s", proxy_command);
84 command_string = percent_expand(tmp, "h", host,
85 "p", strport, (char *)NULL);
88 /* Create pipes for communicating with the proxy. */
89 if (pipe(pin) < 0 || pipe(pout) < 0)
90 fatal("Could not create pipes to communicate with the proxy: %.100s",
93 debug("Executing proxy command: %.500s", command_string);
95 /* Fork and execute the proxy command. */
96 if ((pid = fork()) == 0) {
99 /* Child. Permanently give up superuser privileges. */
100 seteuid(original_real_uid);
101 setuid(original_real_uid);
103 /* Redirect stdin and stdout. */
106 if (dup2(pin[0], 0) < 0)
107 perror("dup2 stdin");
111 if (dup2(pout[1], 1) < 0)
112 perror("dup2 stdout");
113 /* Cannot be 1 because pin allocated two descriptors. */
116 /* Stderr is left as it is so that error messages get
117 printed on the user's terminal. */
118 argv[0] = _PATH_BSHELL;
120 argv[2] = command_string;
123 /* Execute the proxy command. Note that we gave up any
124 extra privileges above. */
125 execv(argv[0], argv);
131 fatal("fork failed: %.100s", strerror(errno));
133 proxy_command_pid = pid; /* save pid to clean up later */
135 /* Close child side of the descriptors. */
139 /* Free the command name. */
140 xfree(command_string);
142 /* Set the connection file descriptors. */
143 packet_set_connection(pout[0], pin[1]);
145 /* Indicate OK return */
150 * Creates a (possibly privileged) socket for use as the ssh connection.
153 ssh_create_socket(int privileged, struct addrinfo *ai)
156 struct addrinfo hints, *res;
159 * If we are running as root and want to connect to a privileged
160 * port, bind our own socket to a privileged port.
163 int p = IPPORT_RESERVED - 1;
165 sock = rresvport_af(&p, ai->ai_family);
168 error("rresvport: af=%d %.100s", ai->ai_family,
171 debug("Allocated local port %d.", p);
174 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
176 error("socket: %.100s", strerror(errno));
178 /* Bind the socket to an alternative local IP address */
179 if (options.bind_address == NULL)
182 memset(&hints, 0, sizeof(hints));
183 hints.ai_family = ai->ai_family;
184 hints.ai_socktype = ai->ai_socktype;
185 hints.ai_protocol = ai->ai_protocol;
186 hints.ai_flags = AI_PASSIVE;
187 gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
189 error("getaddrinfo: %s: %s", options.bind_address,
190 gai_strerror(gaierr));
194 if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
195 error("bind: %s: %s", options.bind_address, strerror(errno));
205 timeout_connect(int sockfd, const struct sockaddr *serv_addr,
206 socklen_t addrlen, int timeout)
211 int optval, rc, result = -1;
214 return (connect(sockfd, serv_addr, addrlen));
216 set_nonblock(sockfd);
217 rc = connect(sockfd, serv_addr, addrlen);
219 unset_nonblock(sockfd);
222 if (errno != EINPROGRESS)
225 fdset = (fd_set *)xcalloc(howmany(sockfd + 1, NFDBITS),
227 FD_SET(sockfd, fdset);
232 rc = select(sockfd + 1, NULL, fdset, NULL, &tv);
233 if (rc != -1 || errno != EINTR)
244 debug("select: %s", strerror(errno));
247 /* Completed or failed */
249 optlen = sizeof(optval);
250 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval,
252 debug("getsockopt: %s", strerror(errno));
260 unset_nonblock(sockfd);
263 /* Should not occur */
264 fatal("Bogus return (%d) from select()", rc);
272 * Opens a TCP/IP connection to the remote server on the given host.
273 * The address of the remote host will be returned in hostaddr.
274 * If port is 0, the default port will be used. If needpriv is true,
275 * a privileged port will be allocated to make the connection.
276 * This requires super-user privileges if needpriv is true.
277 * Connection_attempts specifies the maximum number of tries (one per
278 * second). If proxy_command is non-NULL, it specifies the command (with %h
279 * and %p substituted for host and port, respectively) to use to contact
283 ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
284 u_short port, int family, int connection_attempts,
285 int needpriv, const char *proxy_command)
289 int sock = -1, attempt;
290 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
291 struct addrinfo hints, *ai, *aitop;
293 debug2("ssh_connect: needpriv %d", needpriv);
295 /* If a proxy command is given, connect using it. */
296 if (proxy_command != NULL)
297 return ssh_proxy_connect(host, port, proxy_command);
299 /* No proxy command. */
301 memset(&hints, 0, sizeof(hints));
302 hints.ai_family = family;
303 hints.ai_socktype = SOCK_STREAM;
304 snprintf(strport, sizeof strport, "%u", port);
305 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
306 fatal("%s: %.100s: %s", __progname, host,
307 gai_strerror(gaierr));
309 for (attempt = 0; attempt < connection_attempts; attempt++) {
311 debug("Trying again...");
314 * Loop through addresses for this host, and try each one in
315 * sequence until the connection succeeds.
317 for (ai = aitop; ai; ai = ai->ai_next) {
318 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
320 if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
321 ntop, sizeof(ntop), strport, sizeof(strport),
322 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
323 error("ssh_connect: getnameinfo failed");
326 debug("Connecting to %.200s [%.100s] port %s.",
327 host, ntop, strport);
329 /* Create a socket for connecting. */
330 sock = ssh_create_socket(needpriv, ai);
332 /* Any error is already output */
335 if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
336 options.connection_timeout) >= 0) {
337 /* Successful connection. */
338 memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
341 debug("connect to address %s port %s: %s",
342 ntop, strport, strerror(errno));
348 break; /* Successful connection. */
350 /* Sleep a moment before retrying. */
356 /* Return failure if we didn't get a successful connection. */
358 error("ssh: connect to host %s port %s: %s",
359 host, strport, strerror(errno));
363 debug("Connection established.");
365 /* Set SO_KEEPALIVE if requested. */
366 if (options.tcp_keep_alive &&
367 setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
369 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
371 /* Set the connection. */
372 packet_set_connection(sock, sock);
378 * Waits for the server identification string, and sends our own
379 * identification string.
382 ssh_exchange_identification(void)
384 char buf[256], remote_version[256]; /* must be same size! */
385 int remote_major, remote_minor, mismatch;
386 int connection_in = packet_get_connection_in();
387 int connection_out = packet_get_connection_out();
388 int minor1 = PROTOCOL_MINOR_1;
391 /* Read other side's version identification. */
393 for (i = 0; i < sizeof(buf) - 1; i++) {
394 size_t len = atomicio(read, connection_in, &buf[i], 1);
396 if (len != 1 && errno == EPIPE)
397 fatal("ssh_exchange_identification: Connection closed by remote host");
399 fatal("ssh_exchange_identification: read: %.100s", strerror(errno));
400 if (buf[i] == '\r') {
403 continue; /**XXX wait for \n */
405 if (buf[i] == '\n') {
410 buf[sizeof(buf) - 1] = 0;
411 if (strncmp(buf, "SSH-", 4) == 0)
413 debug("ssh_exchange_identification: %s", buf);
415 server_version_string = xstrdup(buf);
418 * Check that the versions match. In future this might accept
419 * several versions and set appropriate flags to handle them.
421 if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
422 &remote_major, &remote_minor, remote_version) != 3)
423 fatal("Bad remote protocol version identification: '%.100s'", buf);
424 debug("Remote protocol version %d.%d, remote software version %.100s",
425 remote_major, remote_minor, remote_version);
427 compat_datafellows(remote_version);
430 switch (remote_major) {
432 if (remote_minor == 99 &&
433 (options.protocol & SSH_PROTO_2) &&
434 !(options.protocol & SSH_PROTO_1_PREFERRED)) {
438 if (!(options.protocol & SSH_PROTO_1)) {
442 if (remote_minor < 3) {
443 fatal("Remote machine has too old SSH software version.");
444 } else if (remote_minor == 3 || remote_minor == 4) {
445 /* We speak 1.3, too. */
448 if (options.forward_agent) {
449 logit("Agent forwarding disabled for protocol 1.3");
450 options.forward_agent = 0;
455 if (options.protocol & SSH_PROTO_2) {
465 fatal("Protocol major versions differ: %d vs. %d",
466 (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
468 /* Send our own protocol version identification. */
469 snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
470 compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
471 compat20 ? PROTOCOL_MINOR_2 : minor1,
473 if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
474 fatal("write: %.100s", strerror(errno));
475 client_version_string = xstrdup(buf);
476 chop(client_version_string);
477 chop(server_version_string);
478 debug("Local version string %.100s", client_version_string);
481 /* defaults to 'no' */
483 confirm(const char *prompt)
485 const char *msg, *again = "Please type 'yes' or 'no': ";
489 if (options.batch_mode)
491 for (msg = prompt;;msg = again) {
492 p = read_passphrase(msg, RP_ECHO);
494 (p[0] == '\0') || (p[0] == '\n') ||
495 strncasecmp(p, "no", 2) == 0)
497 if (p && strncasecmp(p, "yes", 3) == 0)
507 * check whether the supplied host key is valid, return -1 if the key
508 * is not valid. the user_hostfile will not be updated if 'readonly' is true.
511 check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
512 int readonly, const char *user_hostfile, const char *system_hostfile)
515 const char *type = key_type(host_key);
517 char hostline[1000], *hostp, *fp;
518 HostStatus host_status;
519 HostStatus ip_status;
520 int r, local = 0, host_ip_differ = 0;
522 char ntop[NI_MAXHOST];
524 int len, host_line, ip_line;
525 const char *host_file = NULL, *ip_file = NULL;
528 * Force accepting of the host key for loopback/localhost. The
529 * problem is that if the home directory is NFS-mounted to multiple
530 * machines, localhost will refer to a different machine in each of
531 * them, and the user will get bogus HOST_CHANGED warnings. This
532 * essentially disables host authentication for localhost; however,
533 * this is probably not a real problem.
535 /** hostaddr == 0! */
536 switch (hostaddr->sa_family) {
538 local = (ntohl(((struct sockaddr_in *)hostaddr)->
539 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
540 salen = sizeof(struct sockaddr_in);
543 local = IN6_IS_ADDR_LOOPBACK(
544 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
545 salen = sizeof(struct sockaddr_in6);
549 salen = sizeof(struct sockaddr_storage);
552 if (options.no_host_authentication_for_localhost == 1 && local &&
553 options.host_key_alias == NULL) {
554 debug("Forcing accepting of host key for "
555 "loopback/localhost.");
560 * We don't have the remote ip-address for connections
561 * using a proxy command
563 if (options.proxy_command == NULL) {
564 if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
565 NULL, 0, NI_NUMERICHOST) != 0)
566 fatal("check_host_key: getnameinfo failed");
569 ip = xstrdup("<no hostip for proxy command>");
572 * Turn off check_host_ip if the connection is to localhost, via proxy
573 * command or if we don't have a hostname to compare with
575 if (options.check_host_ip &&
576 (local || strcmp(host, ip) == 0 || options.proxy_command != NULL))
577 options.check_host_ip = 0;
580 * Allow the user to record the key under a different name. This is
581 * useful for ssh tunneling over forwarded connections or if you run
582 * multiple sshd's on different ports on the same machine.
584 if (options.host_key_alias != NULL) {
585 host = options.host_key_alias;
586 debug("using hostkeyalias: %s", host);
590 * Store the host key from the known host file in here so that we can
591 * compare it with the key for the IP address.
593 file_key = key_new(host_key->type);
596 * Check if the host key is present in the user's list of known
597 * hosts or in the systemwide list.
599 host_file = user_hostfile;
600 host_status = check_host_in_hostfile(host_file, host, host_key,
601 file_key, &host_line);
602 if (host_status == HOST_NEW) {
603 host_file = system_hostfile;
604 host_status = check_host_in_hostfile(host_file, host, host_key,
605 file_key, &host_line);
608 * Also perform check for the ip address, skip the check if we are
609 * localhost or the hostname was an ip address to begin with
611 if (options.check_host_ip) {
612 Key *ip_key = key_new(host_key->type);
614 ip_file = user_hostfile;
615 ip_status = check_host_in_hostfile(ip_file, ip, host_key,
617 if (ip_status == HOST_NEW) {
618 ip_file = system_hostfile;
619 ip_status = check_host_in_hostfile(ip_file, ip,
620 host_key, ip_key, &ip_line);
622 if (host_status == HOST_CHANGED &&
623 (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
628 ip_status = host_status;
632 switch (host_status) {
634 /* The host is known and the key matches. */
635 debug("Host '%.200s' is known and matches the %s host key.",
637 debug("Found key in %s:%d", host_file, host_line);
638 if (options.check_host_ip && ip_status == HOST_NEW) {
640 logit("%s host key for IP address "
641 "'%.128s' not in list of known hosts.",
643 else if (!add_host_to_hostfile(user_hostfile, ip,
644 host_key, options.hash_known_hosts))
645 logit("Failed to add the %s host key for IP "
646 "address '%.128s' to the list of known "
647 "hosts (%.30s).", type, ip, user_hostfile);
649 logit("Warning: Permanently added the %s host "
650 "key for IP address '%.128s' to the list "
651 "of known hosts.", type, ip);
657 /* The host is new. */
658 if (options.strict_host_key_checking == 1) {
660 * User has requested strict host key checking. We
661 * will not add the host key automatically. The only
662 * alternative left is to abort.
664 error("No %s host key is known for %.200s and you "
665 "have requested strict checking.", type, host);
667 } else if (options.strict_host_key_checking == 2) {
668 char msg1[1024], msg2[1024];
670 if (show_other_keys(host, host_key))
671 snprintf(msg1, sizeof(msg1),
672 "\nbut keys of different type are already"
673 " known for this host.");
675 snprintf(msg1, sizeof(msg1), ".");
677 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
679 if (options.verify_host_key_dns) {
680 if (matching_host_key_dns)
681 snprintf(msg2, sizeof(msg2),
682 "Matching host key fingerprint"
685 snprintf(msg2, sizeof(msg2),
686 "No matching host key fingerprint"
689 snprintf(msg, sizeof(msg),
690 "The authenticity of host '%.200s (%s)' can't be "
692 "%s key fingerprint is %s.\n%s"
693 "Are you sure you want to continue connecting "
695 host, ip, msg1, type, fp, msg2);
701 * If not in strict mode, add the key automatically to the
702 * local known_hosts file.
704 if (options.check_host_ip && ip_status == HOST_NEW) {
705 snprintf(hostline, sizeof(hostline), "%s,%s",
708 if (options.hash_known_hosts) {
709 /* Add hash of host and IP separately */
710 r = add_host_to_hostfile(user_hostfile, host,
711 host_key, options.hash_known_hosts) &&
712 add_host_to_hostfile(user_hostfile, ip,
713 host_key, options.hash_known_hosts);
715 /* Add unhashed "host,ip" */
716 r = add_host_to_hostfile(user_hostfile,
718 options.hash_known_hosts);
721 r = add_host_to_hostfile(user_hostfile, host, host_key,
722 options.hash_known_hosts);
727 logit("Failed to add the host to the list of known "
728 "hosts (%.500s).", user_hostfile);
730 logit("Warning: Permanently added '%.200s' (%s) to the "
731 "list of known hosts.", hostp, type);
734 if (options.check_host_ip && host_ip_differ) {
736 if (ip_status == HOST_NEW)
737 key_msg = "is unknown";
738 else if (ip_status == HOST_OK)
739 key_msg = "is unchanged";
741 key_msg = "has a different value";
742 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
743 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
744 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
745 error("The %s host key for %s has changed,", type, host);
746 error("and the key for the according IP address %s", ip);
747 error("%s. This could either mean that", key_msg);
748 error("DNS SPOOFING is happening or the IP address for the host");
749 error("and its host key have changed at the same time.");
750 if (ip_status != HOST_NEW)
751 error("Offending key for IP in %s:%d", ip_file, ip_line);
753 /* The host key has changed. */
754 warn_changed_key(host_key);
755 error("Add correct host key in %.100s to get rid of this message.",
757 error("Offending key in %s:%d", host_file, host_line);
760 * If strict host key checking is in use, the user will have
761 * to edit the key manually and we can only abort.
763 if (options.strict_host_key_checking) {
764 error("%s host key for %.200s has changed and you have "
765 "requested strict checking.", type, host);
770 * If strict host key checking has not been requested, allow
771 * the connection but without MITM-able authentication or
774 if (options.password_authentication) {
775 error("Password authentication is disabled to avoid "
776 "man-in-the-middle attacks.");
777 options.password_authentication = 0;
779 if (options.kbd_interactive_authentication) {
780 error("Keyboard-interactive authentication is disabled"
781 " to avoid man-in-the-middle attacks.");
782 options.kbd_interactive_authentication = 0;
783 options.challenge_response_authentication = 0;
785 if (options.challenge_response_authentication) {
786 error("Challenge/response authentication is disabled"
787 " to avoid man-in-the-middle attacks.");
788 options.challenge_response_authentication = 0;
790 if (options.forward_agent) {
791 error("Agent forwarding is disabled to avoid "
792 "man-in-the-middle attacks.");
793 options.forward_agent = 0;
795 if (options.forward_x11) {
796 error("X11 forwarding is disabled to avoid "
797 "man-in-the-middle attacks.");
798 options.forward_x11 = 0;
800 if (options.num_local_forwards > 0 ||
801 options.num_remote_forwards > 0) {
802 error("Port forwarding is disabled to avoid "
803 "man-in-the-middle attacks.");
804 options.num_local_forwards =
805 options.num_remote_forwards = 0;
808 * XXX Should permit the user to change to use the new id.
809 * This could be done by converting the host key to an
810 * identifying sentence, tell that the host identifies itself
811 * by that sentence, and ask the user if he/she whishes to
812 * accept the authentication.
816 fatal("internal error");
820 if (options.check_host_ip && host_status != HOST_CHANGED &&
821 ip_status == HOST_CHANGED) {
822 snprintf(msg, sizeof(msg),
823 "Warning: the %s host key for '%.200s' "
824 "differs from the key for the IP address '%.128s'"
825 "\nOffending key for IP in %s:%d",
826 type, host, ip, ip_file, ip_line);
827 if (host_status == HOST_OK) {
829 snprintf(msg + len, sizeof(msg) - len,
830 "\nMatching host key in %s:%d",
831 host_file, host_line);
833 if (options.strict_host_key_checking == 1) {
835 error("Exiting, you have requested strict checking.");
837 } else if (options.strict_host_key_checking == 2) {
838 strlcat(msg, "\nAre you sure you want "
839 "to continue connecting (yes/no)? ", sizeof(msg));
855 /* returns 0 if key verifies or -1 if key does NOT verify */
857 verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
862 if (options.verify_host_key_dns &&
863 verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
865 if (flags & DNS_VERIFY_FOUND) {
867 if (options.verify_host_key_dns == 1 &&
868 flags & DNS_VERIFY_MATCH &&
869 flags & DNS_VERIFY_SECURE)
872 if (flags & DNS_VERIFY_MATCH) {
873 matching_host_key_dns = 1;
875 warn_changed_key(host_key);
876 error("Update the SSHFP RR in DNS with the new "
877 "host key to get rid of this message.");
882 /* return ok if the key can be found in an old keyfile */
883 if (stat(options.system_hostfile2, &st) == 0 ||
884 stat(options.user_hostfile2, &st) == 0) {
885 if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1,
886 options.user_hostfile2, options.system_hostfile2) == 0)
889 return check_host_key(host, hostaddr, host_key, /*readonly*/ 0,
890 options.user_hostfile, options.system_hostfile);
894 * Starts a dialog with the server, and authenticates the current user on the
895 * server. This does not need any extra privileges. The basic connection
896 * to the server must already have been established before this is called.
897 * If login fails, this function prints an error and never returns.
898 * This function does not require super-user privileges.
901 ssh_login(Sensitive *sensitive, const char *orighost,
902 struct sockaddr *hostaddr, struct passwd *pw)
905 char *server_user, *local_user;
907 local_user = xstrdup(pw->pw_name);
908 server_user = options.user ? options.user : local_user;
910 /* Convert the user-supplied hostname into all lowercase. */
911 host = xstrdup(orighost);
912 for (cp = host; *cp; cp++)
914 *cp = (char)tolower(*cp);
916 /* Exchange protocol version identification strings with the server. */
917 ssh_exchange_identification();
919 /* Put the connection into non-blocking mode. */
920 packet_set_nonblocking();
923 /* authenticate user */
925 ssh_kex2(host, hostaddr);
926 ssh_userauth2(local_user, server_user, host, sensitive);
928 ssh_kex(host, hostaddr);
929 ssh_userauth1(local_user, server_user, host, sensitive);
934 ssh_put_password(char *password)
939 if (datafellows & SSH_BUG_PASSWORDPAD) {
940 packet_put_cstring(password);
943 size = roundup(strlen(password) + 1, 32);
944 padded = xcalloc(1, size);
945 strlcpy(padded, password, size);
946 packet_put_string(padded, size);
947 memset(padded, 0, size);
952 show_key_from_file(const char *file, const char *host, int keytype)
958 found = key_new(keytype);
959 if ((ret = lookup_key_in_hostfile_by_type(file, host,
960 keytype, found, &line))) {
961 fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
962 logit("WARNING: %s key found for host %s\n"
964 "%s key fingerprint %s.",
965 key_type(found), host, file, line,
966 key_type(found), fp);
973 /* print all known host keys for a given host, but skip keys of given type */
975 show_other_keys(const char *host, Key *key)
977 int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
980 for (i = 0; type[i] != -1; i++) {
981 if (type[i] == key->type)
983 if (type[i] != KEY_RSA1 &&
984 show_key_from_file(options.user_hostfile2, host, type[i])) {
988 if (type[i] != KEY_RSA1 &&
989 show_key_from_file(options.system_hostfile2, host, type[i])) {
993 if (show_key_from_file(options.user_hostfile, host, type[i])) {
997 if (show_key_from_file(options.system_hostfile, host, type[i])) {
1001 debug2("no key of type %d for host %s", type[i], host);
1007 warn_changed_key(Key *host_key)
1010 const char *type = key_type(host_key);
1012 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
1014 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1015 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
1016 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1017 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
1018 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
1019 error("It is also possible that the %s host key has just been changed.", type);
1020 error("The fingerprint for the %s key sent by the remote host is\n%s.",
1022 error("Please contact your system administrator.");
1028 * Execute a local command
1031 ssh_local_cmd(const char *args)
1037 if (!options.permit_local_command ||
1038 args == NULL || !*args)
1041 if ((shell = getenv("SHELL")) == NULL)
1042 shell = _PATH_BSHELL;
1046 debug3("Executing %s -c \"%s\"", shell, args);
1047 execl(shell, shell, "-c", args, (char *)NULL);
1048 error("Couldn't execute %s -c \"%s\": %s",
1049 shell, args, strerror(errno));
1051 } else if (pid == -1)
1052 fatal("fork failed: %.100s", strerror(errno));
1053 while (waitpid(pid, &status, 0) == -1)
1055 fatal("Couldn't wait for child: %s", strerror(errno));
1057 if (!WIFEXITED(status))
1060 return (WEXITSTATUS(status));