1 /* $OpenBSD: sshconnect.c,v 1.186 2006/07/03 08:54:20 stevesk 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"
44 char *client_version_string = NULL;
45 char *server_version_string = NULL;
47 static int matching_host_key_dns = 0;
50 extern Options options;
51 extern char *__progname;
52 extern uid_t original_real_uid;
53 extern uid_t original_effective_uid;
54 extern pid_t proxy_command_pid;
56 #ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */
57 #define INET6_ADDRSTRLEN 46
60 static int show_other_keys(const char *, Key *);
61 static void warn_changed_key(Key *);
64 * Connect to the given ssh server using a proxy command.
67 ssh_proxy_connect(const char *host, u_short port, const char *proxy_command)
69 char *command_string, *tmp;
72 char strport[NI_MAXSERV];
74 /* Convert the port number into a string. */
75 snprintf(strport, sizeof strport, "%hu", port);
78 * Build the final command string in the buffer by making the
79 * appropriate substitutions to the given proxy command.
81 * Use "exec" to avoid "sh -c" processes on some platforms
84 xasprintf(&tmp, "exec %s", proxy_command);
85 command_string = percent_expand(tmp, "h", host,
86 "p", strport, (char *)NULL);
89 /* Create pipes for communicating with the proxy. */
90 if (pipe(pin) < 0 || pipe(pout) < 0)
91 fatal("Could not create pipes to communicate with the proxy: %.100s",
94 debug("Executing proxy command: %.500s", command_string);
96 /* Fork and execute the proxy command. */
97 if ((pid = fork()) == 0) {
100 /* Child. Permanently give up superuser privileges. */
101 permanently_drop_suid(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 fatal("ssh_exchange_identification: No banner received");
412 buf[sizeof(buf) - 1] = 0;
413 if (strncmp(buf, "SSH-", 4) == 0)
415 debug("ssh_exchange_identification: %s", buf);
417 server_version_string = xstrdup(buf);
420 * Check that the versions match. In future this might accept
421 * several versions and set appropriate flags to handle them.
423 if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
424 &remote_major, &remote_minor, remote_version) != 3)
425 fatal("Bad remote protocol version identification: '%.100s'", buf);
426 debug("Remote protocol version %d.%d, remote software version %.100s",
427 remote_major, remote_minor, remote_version);
429 compat_datafellows(remote_version);
432 switch (remote_major) {
434 if (remote_minor == 99 &&
435 (options.protocol & SSH_PROTO_2) &&
436 !(options.protocol & SSH_PROTO_1_PREFERRED)) {
440 if (!(options.protocol & SSH_PROTO_1)) {
444 if (remote_minor < 3) {
445 fatal("Remote machine has too old SSH software version.");
446 } else if (remote_minor == 3 || remote_minor == 4) {
447 /* We speak 1.3, too. */
450 if (options.forward_agent) {
451 logit("Agent forwarding disabled for protocol 1.3");
452 options.forward_agent = 0;
457 if (options.protocol & SSH_PROTO_2) {
467 fatal("Protocol major versions differ: %d vs. %d",
468 (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
470 /* Send our own protocol version identification. */
471 snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
472 compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
473 compat20 ? PROTOCOL_MINOR_2 : minor1,
475 if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
476 fatal("write: %.100s", strerror(errno));
477 client_version_string = xstrdup(buf);
478 chop(client_version_string);
479 chop(server_version_string);
480 debug("Local version string %.100s", client_version_string);
483 /* defaults to 'no' */
485 confirm(const char *prompt)
487 const char *msg, *again = "Please type 'yes' or 'no': ";
491 if (options.batch_mode)
493 for (msg = prompt;;msg = again) {
494 p = read_passphrase(msg, RP_ECHO);
496 (p[0] == '\0') || (p[0] == '\n') ||
497 strncasecmp(p, "no", 2) == 0)
499 if (p && strncasecmp(p, "yes", 3) == 0)
509 * check whether the supplied host key is valid, return -1 if the key
510 * is not valid. the user_hostfile will not be updated if 'readonly' is true.
513 check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
514 int readonly, const char *user_hostfile, const char *system_hostfile)
517 const char *type = key_type(host_key);
519 char hostline[1000], *hostp, *fp;
520 HostStatus host_status;
521 HostStatus ip_status;
522 int r, local = 0, host_ip_differ = 0;
524 char ntop[NI_MAXHOST];
526 int len, host_line, ip_line;
527 const char *host_file = NULL, *ip_file = NULL;
530 * Force accepting of the host key for loopback/localhost. The
531 * problem is that if the home directory is NFS-mounted to multiple
532 * machines, localhost will refer to a different machine in each of
533 * them, and the user will get bogus HOST_CHANGED warnings. This
534 * essentially disables host authentication for localhost; however,
535 * this is probably not a real problem.
537 /** hostaddr == 0! */
538 switch (hostaddr->sa_family) {
540 local = (ntohl(((struct sockaddr_in *)hostaddr)->
541 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
542 salen = sizeof(struct sockaddr_in);
545 local = IN6_IS_ADDR_LOOPBACK(
546 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
547 salen = sizeof(struct sockaddr_in6);
551 salen = sizeof(struct sockaddr_storage);
554 if (options.no_host_authentication_for_localhost == 1 && local &&
555 options.host_key_alias == NULL) {
556 debug("Forcing accepting of host key for "
557 "loopback/localhost.");
562 * We don't have the remote ip-address for connections
563 * using a proxy command
565 if (options.proxy_command == NULL) {
566 if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
567 NULL, 0, NI_NUMERICHOST) != 0)
568 fatal("check_host_key: getnameinfo failed");
571 ip = xstrdup("<no hostip for proxy command>");
574 * Turn off check_host_ip if the connection is to localhost, via proxy
575 * command or if we don't have a hostname to compare with
577 if (options.check_host_ip &&
578 (local || strcmp(host, ip) == 0 || options.proxy_command != NULL))
579 options.check_host_ip = 0;
582 * Allow the user to record the key under a different name. This is
583 * useful for ssh tunneling over forwarded connections or if you run
584 * multiple sshd's on different ports on the same machine.
586 if (options.host_key_alias != NULL) {
587 host = options.host_key_alias;
588 debug("using hostkeyalias: %s", host);
592 * Store the host key from the known host file in here so that we can
593 * compare it with the key for the IP address.
595 file_key = key_new(host_key->type);
598 * Check if the host key is present in the user's list of known
599 * hosts or in the systemwide list.
601 host_file = user_hostfile;
602 host_status = check_host_in_hostfile(host_file, host, host_key,
603 file_key, &host_line);
604 if (host_status == HOST_NEW) {
605 host_file = system_hostfile;
606 host_status = check_host_in_hostfile(host_file, host, host_key,
607 file_key, &host_line);
610 * Also perform check for the ip address, skip the check if we are
611 * localhost or the hostname was an ip address to begin with
613 if (options.check_host_ip) {
614 Key *ip_key = key_new(host_key->type);
616 ip_file = user_hostfile;
617 ip_status = check_host_in_hostfile(ip_file, ip, host_key,
619 if (ip_status == HOST_NEW) {
620 ip_file = system_hostfile;
621 ip_status = check_host_in_hostfile(ip_file, ip,
622 host_key, ip_key, &ip_line);
624 if (host_status == HOST_CHANGED &&
625 (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
630 ip_status = host_status;
634 switch (host_status) {
636 /* The host is known and the key matches. */
637 debug("Host '%.200s' is known and matches the %s host key.",
639 debug("Found key in %s:%d", host_file, host_line);
640 if (options.check_host_ip && ip_status == HOST_NEW) {
642 logit("%s host key for IP address "
643 "'%.128s' not in list of known hosts.",
645 else if (!add_host_to_hostfile(user_hostfile, ip,
646 host_key, options.hash_known_hosts))
647 logit("Failed to add the %s host key for IP "
648 "address '%.128s' to the list of known "
649 "hosts (%.30s).", type, ip, user_hostfile);
651 logit("Warning: Permanently added the %s host "
652 "key for IP address '%.128s' to the list "
653 "of known hosts.", type, ip);
659 /* The host is new. */
660 if (options.strict_host_key_checking == 1) {
662 * User has requested strict host key checking. We
663 * will not add the host key automatically. The only
664 * alternative left is to abort.
666 error("No %s host key is known for %.200s and you "
667 "have requested strict checking.", type, host);
669 } else if (options.strict_host_key_checking == 2) {
670 char msg1[1024], msg2[1024];
672 if (show_other_keys(host, host_key))
673 snprintf(msg1, sizeof(msg1),
674 "\nbut keys of different type are already"
675 " known for this host.");
677 snprintf(msg1, sizeof(msg1), ".");
679 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
681 if (options.verify_host_key_dns) {
682 if (matching_host_key_dns)
683 snprintf(msg2, sizeof(msg2),
684 "Matching host key fingerprint"
687 snprintf(msg2, sizeof(msg2),
688 "No matching host key fingerprint"
691 snprintf(msg, sizeof(msg),
692 "The authenticity of host '%.200s (%s)' can't be "
694 "%s key fingerprint is %s.\n%s"
695 "Are you sure you want to continue connecting "
697 host, ip, msg1, type, fp, msg2);
703 * If not in strict mode, add the key automatically to the
704 * local known_hosts file.
706 if (options.check_host_ip && ip_status == HOST_NEW) {
707 snprintf(hostline, sizeof(hostline), "%s,%s",
710 if (options.hash_known_hosts) {
711 /* Add hash of host and IP separately */
712 r = add_host_to_hostfile(user_hostfile, host,
713 host_key, options.hash_known_hosts) &&
714 add_host_to_hostfile(user_hostfile, ip,
715 host_key, options.hash_known_hosts);
717 /* Add unhashed "host,ip" */
718 r = add_host_to_hostfile(user_hostfile,
720 options.hash_known_hosts);
723 r = add_host_to_hostfile(user_hostfile, host, host_key,
724 options.hash_known_hosts);
729 logit("Failed to add the host to the list of known "
730 "hosts (%.500s).", user_hostfile);
732 logit("Warning: Permanently added '%.200s' (%s) to the "
733 "list of known hosts.", hostp, type);
736 if (options.check_host_ip && host_ip_differ) {
738 if (ip_status == HOST_NEW)
739 key_msg = "is unknown";
740 else if (ip_status == HOST_OK)
741 key_msg = "is unchanged";
743 key_msg = "has a different value";
744 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
745 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
746 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
747 error("The %s host key for %s has changed,", type, host);
748 error("and the key for the according IP address %s", ip);
749 error("%s. This could either mean that", key_msg);
750 error("DNS SPOOFING is happening or the IP address for the host");
751 error("and its host key have changed at the same time.");
752 if (ip_status != HOST_NEW)
753 error("Offending key for IP in %s:%d", ip_file, ip_line);
755 /* The host key has changed. */
756 warn_changed_key(host_key);
757 error("Add correct host key in %.100s to get rid of this message.",
759 error("Offending key in %s:%d", host_file, host_line);
762 * If strict host key checking is in use, the user will have
763 * to edit the key manually and we can only abort.
765 if (options.strict_host_key_checking) {
766 error("%s host key for %.200s has changed and you have "
767 "requested strict checking.", type, host);
772 * If strict host key checking has not been requested, allow
773 * the connection but without MITM-able authentication or
776 if (options.password_authentication) {
777 error("Password authentication is disabled to avoid "
778 "man-in-the-middle attacks.");
779 options.password_authentication = 0;
781 if (options.kbd_interactive_authentication) {
782 error("Keyboard-interactive authentication is disabled"
783 " to avoid man-in-the-middle attacks.");
784 options.kbd_interactive_authentication = 0;
785 options.challenge_response_authentication = 0;
787 if (options.challenge_response_authentication) {
788 error("Challenge/response authentication is disabled"
789 " to avoid man-in-the-middle attacks.");
790 options.challenge_response_authentication = 0;
792 if (options.forward_agent) {
793 error("Agent forwarding is disabled to avoid "
794 "man-in-the-middle attacks.");
795 options.forward_agent = 0;
797 if (options.forward_x11) {
798 error("X11 forwarding is disabled to avoid "
799 "man-in-the-middle attacks.");
800 options.forward_x11 = 0;
802 if (options.num_local_forwards > 0 ||
803 options.num_remote_forwards > 0) {
804 error("Port forwarding is disabled to avoid "
805 "man-in-the-middle attacks.");
806 options.num_local_forwards =
807 options.num_remote_forwards = 0;
810 * XXX Should permit the user to change to use the new id.
811 * This could be done by converting the host key to an
812 * identifying sentence, tell that the host identifies itself
813 * by that sentence, and ask the user if he/she whishes to
814 * accept the authentication.
818 fatal("internal error");
822 if (options.check_host_ip && host_status != HOST_CHANGED &&
823 ip_status == HOST_CHANGED) {
824 snprintf(msg, sizeof(msg),
825 "Warning: the %s host key for '%.200s' "
826 "differs from the key for the IP address '%.128s'"
827 "\nOffending key for IP in %s:%d",
828 type, host, ip, ip_file, ip_line);
829 if (host_status == HOST_OK) {
831 snprintf(msg + len, sizeof(msg) - len,
832 "\nMatching host key in %s:%d",
833 host_file, host_line);
835 if (options.strict_host_key_checking == 1) {
837 error("Exiting, you have requested strict checking.");
839 } else if (options.strict_host_key_checking == 2) {
840 strlcat(msg, "\nAre you sure you want "
841 "to continue connecting (yes/no)? ", sizeof(msg));
857 /* returns 0 if key verifies or -1 if key does NOT verify */
859 verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
864 if (options.verify_host_key_dns &&
865 verify_host_key_dns(host, hostaddr, host_key, &flags) == 0) {
867 if (flags & DNS_VERIFY_FOUND) {
869 if (options.verify_host_key_dns == 1 &&
870 flags & DNS_VERIFY_MATCH &&
871 flags & DNS_VERIFY_SECURE)
874 if (flags & DNS_VERIFY_MATCH) {
875 matching_host_key_dns = 1;
877 warn_changed_key(host_key);
878 error("Update the SSHFP RR in DNS with the new "
879 "host key to get rid of this message.");
884 /* return ok if the key can be found in an old keyfile */
885 if (stat(options.system_hostfile2, &st) == 0 ||
886 stat(options.user_hostfile2, &st) == 0) {
887 if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1,
888 options.user_hostfile2, options.system_hostfile2) == 0)
891 return check_host_key(host, hostaddr, host_key, /*readonly*/ 0,
892 options.user_hostfile, options.system_hostfile);
896 * Starts a dialog with the server, and authenticates the current user on the
897 * server. This does not need any extra privileges. The basic connection
898 * to the server must already have been established before this is called.
899 * If login fails, this function prints an error and never returns.
900 * This function does not require super-user privileges.
903 ssh_login(Sensitive *sensitive, const char *orighost,
904 struct sockaddr *hostaddr, struct passwd *pw)
907 char *server_user, *local_user;
909 local_user = xstrdup(pw->pw_name);
910 server_user = options.user ? options.user : local_user;
912 /* Convert the user-supplied hostname into all lowercase. */
913 host = xstrdup(orighost);
914 for (cp = host; *cp; cp++)
916 *cp = (char)tolower(*cp);
918 /* Exchange protocol version identification strings with the server. */
919 ssh_exchange_identification();
921 /* Put the connection into non-blocking mode. */
922 packet_set_nonblocking();
925 /* authenticate user */
927 ssh_kex2(host, hostaddr);
928 ssh_userauth2(local_user, server_user, host, sensitive);
930 ssh_kex(host, hostaddr);
931 ssh_userauth1(local_user, server_user, host, sensitive);
937 ssh_put_password(char *password)
942 if (datafellows & SSH_BUG_PASSWORDPAD) {
943 packet_put_cstring(password);
946 size = roundup(strlen(password) + 1, 32);
947 padded = xcalloc(1, size);
948 strlcpy(padded, password, size);
949 packet_put_string(padded, size);
950 memset(padded, 0, size);
955 show_key_from_file(const char *file, const char *host, int keytype)
961 found = key_new(keytype);
962 if ((ret = lookup_key_in_hostfile_by_type(file, host,
963 keytype, found, &line))) {
964 fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
965 logit("WARNING: %s key found for host %s\n"
967 "%s key fingerprint %s.",
968 key_type(found), host, file, line,
969 key_type(found), fp);
976 /* print all known host keys for a given host, but skip keys of given type */
978 show_other_keys(const char *host, Key *key)
980 int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
983 for (i = 0; type[i] != -1; i++) {
984 if (type[i] == key->type)
986 if (type[i] != KEY_RSA1 &&
987 show_key_from_file(options.user_hostfile2, host, type[i])) {
991 if (type[i] != KEY_RSA1 &&
992 show_key_from_file(options.system_hostfile2, host, type[i])) {
996 if (show_key_from_file(options.user_hostfile, host, type[i])) {
1000 if (show_key_from_file(options.system_hostfile, host, type[i])) {
1004 debug2("no key of type %d for host %s", type[i], host);
1010 warn_changed_key(Key *host_key)
1013 const char *type = key_type(host_key);
1015 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
1017 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1018 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
1019 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
1020 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
1021 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
1022 error("It is also possible that the %s host key has just been changed.", type);
1023 error("The fingerprint for the %s key sent by the remote host is\n%s.",
1025 error("Please contact your system administrator.");
1031 * Execute a local command
1034 ssh_local_cmd(const char *args)
1040 if (!options.permit_local_command ||
1041 args == NULL || !*args)
1044 if ((shell = getenv("SHELL")) == NULL)
1045 shell = _PATH_BSHELL;
1049 debug3("Executing %s -c \"%s\"", shell, args);
1050 execl(shell, shell, "-c", args, (char *)NULL);
1051 error("Couldn't execute %s -c \"%s\": %s",
1052 shell, args, strerror(errno));
1054 } else if (pid == -1)
1055 fatal("fork failed: %.100s", strerror(errno));
1056 while (waitpid(pid, &status, 0) == -1)
1058 fatal("Couldn't wait for child: %s", strerror(errno));
1060 if (!WIFEXITED(status))
1063 return (WEXITSTATUS(status));