2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Code to connect to a remote host, and to perform the client side of the
6 * login (authentication) dialog.
8 * As far as I am concerned, the code I have written for this software
9 * can be used freely for any purpose. Any derived versions of this
10 * software must be clearly marked as such, and if the derived work is
11 * incompatible with the protocol description in the RFC file, it must be
12 * called by a name other than "ssh" or "Secure Shell".
16 RCSID("$OpenBSD: sshconnect.c,v 1.146 2003/06/28 16:23:06 deraadt Exp $");
18 #include <openssl/bn.h>
28 #include "sshconnect.h"
40 char *client_version_string = NULL;
41 char *server_version_string = NULL;
44 int verified_host_key_dns = 0;
48 extern Options options;
49 extern char *__progname;
50 extern uid_t original_real_uid;
51 extern uid_t original_effective_uid;
52 extern pid_t proxy_command_pid;
54 #ifndef INET6_ADDRSTRLEN /* for non IPv6 machines */
55 #define INET6_ADDRSTRLEN 46
58 static int show_other_keys(const char *, Key *);
61 * Connect to the given ssh server using a proxy command.
64 ssh_proxy_connect(const char *host, u_short port, const char *proxy_command)
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 buffer_init(&command);
84 buffer_append(&command, "exec ", 5);
86 for (cp = proxy_command; *cp; cp++) {
87 if (cp[0] == '%' && cp[1] == '%') {
88 buffer_append(&command, "%", 1);
92 if (cp[0] == '%' && cp[1] == 'h') {
93 buffer_append(&command, host, strlen(host));
97 if (cp[0] == '%' && cp[1] == 'p') {
98 buffer_append(&command, strport, strlen(strport));
102 buffer_append(&command, cp, 1);
104 buffer_append(&command, "\0", 1);
106 /* Get the final command string. */
107 command_string = buffer_ptr(&command);
109 /* Create pipes for communicating with the proxy. */
110 if (pipe(pin) < 0 || pipe(pout) < 0)
111 fatal("Could not create pipes to communicate with the proxy: %.100s",
114 debug("Executing proxy command: %.500s", command_string);
116 /* Fork and execute the proxy command. */
117 if ((pid = fork()) == 0) {
120 /* Child. Permanently give up superuser privileges. */
121 seteuid(original_real_uid);
122 setuid(original_real_uid);
124 /* Redirect stdin and stdout. */
127 if (dup2(pin[0], 0) < 0)
128 perror("dup2 stdin");
132 if (dup2(pout[1], 1) < 0)
133 perror("dup2 stdout");
134 /* Cannot be 1 because pin allocated two descriptors. */
137 /* Stderr is left as it is so that error messages get
138 printed on the user's terminal. */
139 argv[0] = _PATH_BSHELL;
141 argv[2] = command_string;
144 /* Execute the proxy command. Note that we gave up any
145 extra privileges above. */
146 execv(argv[0], argv);
152 fatal("fork failed: %.100s", strerror(errno));
154 proxy_command_pid = pid; /* save pid to clean up later */
156 /* Close child side of the descriptors. */
160 /* Free the command name. */
161 buffer_free(&command);
163 /* Set the connection file descriptors. */
164 packet_set_connection(pout[0], pin[1]);
166 /* Indicate OK return */
171 * Creates a (possibly privileged) socket for use as the ssh connection.
174 ssh_create_socket(int privileged, struct addrinfo *ai)
177 struct addrinfo hints, *res;
180 * If we are running as root and want to connect to a privileged
181 * port, bind our own socket to a privileged port.
184 int p = IPPORT_RESERVED - 1;
186 sock = rresvport_af(&p, ai->ai_family);
189 error("rresvport: af=%d %.100s", ai->ai_family,
192 debug("Allocated local port %d.", p);
195 sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
197 error("socket: %.100s", strerror(errno));
199 /* Bind the socket to an alternative local IP address */
200 if (options.bind_address == NULL)
203 memset(&hints, 0, sizeof(hints));
204 hints.ai_family = ai->ai_family;
205 hints.ai_socktype = ai->ai_socktype;
206 hints.ai_protocol = ai->ai_protocol;
207 hints.ai_flags = AI_PASSIVE;
208 gaierr = getaddrinfo(options.bind_address, "0", &hints, &res);
210 error("getaddrinfo: %s: %s", options.bind_address,
211 gai_strerror(gaierr));
215 if (bind(sock, res->ai_addr, res->ai_addrlen) < 0) {
216 error("bind: %s: %s", options.bind_address, strerror(errno));
226 timeout_connect(int sockfd, const struct sockaddr *serv_addr,
227 socklen_t addrlen, int timeout)
232 int fdsetsz, optval, rc, result = -1;
235 return (connect(sockfd, serv_addr, addrlen));
237 if (fcntl(sockfd, F_SETFL, O_NONBLOCK) < 0)
240 rc = connect(sockfd, serv_addr, addrlen);
243 if (errno != EINPROGRESS)
246 fdsetsz = howmany(sockfd + 1, NFDBITS) * sizeof(fd_mask);
247 fdset = (fd_set *)xmalloc(fdsetsz);
249 memset(fdset, '\0', fdsetsz);
250 FD_SET(sockfd, fdset);
255 rc = select(sockfd + 1, NULL, fdset, NULL, &tv);
256 if (rc != -1 || errno != EINTR)
267 debug("select: %s", strerror(errno));
270 /* Completed or failed */
272 optlen = sizeof(optval);
273 if (getsockopt(sockfd, SOL_SOCKET, SO_ERROR, &optval,
275 debug("getsockopt: %s", strerror(errno));
284 /* Should not occur */
285 fatal("Bogus return (%d) from select()", rc);
293 * Opens a TCP/IP connection to the remote server on the given host.
294 * The address of the remote host will be returned in hostaddr.
295 * If port is 0, the default port will be used. If needpriv is true,
296 * a privileged port will be allocated to make the connection.
297 * This requires super-user privileges if needpriv is true.
298 * Connection_attempts specifies the maximum number of tries (one per
299 * second). If proxy_command is non-NULL, it specifies the command (with %h
300 * and %p substituted for host and port, respectively) to use to contact
304 * ECONNREFUSED if we got a "Connection Refused" by the peer on any address
305 * ECONNABORTED if we failed without a "Connection refused"
306 * Suitable error messages for the connection failure will already have been
310 ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
311 u_short port, int family, int connection_attempts,
312 int needpriv, const char *proxy_command)
316 int sock = -1, attempt;
317 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
318 struct addrinfo hints, *ai, *aitop;
321 * Did we get only other errors than "Connection refused" (which
322 * should block fallback to rsh and similar), or did we get at least
323 * one "Connection refused"?
325 int full_failure = 1;
327 debug2("ssh_connect: needpriv %d", needpriv);
329 /* Get default port if port has not been set. */
331 sp = getservbyname(SSH_SERVICE_NAME, "tcp");
333 port = ntohs(sp->s_port);
335 port = SSH_DEFAULT_PORT;
337 /* If a proxy command is given, connect using it. */
338 if (proxy_command != NULL)
339 return ssh_proxy_connect(host, port, proxy_command);
341 /* No proxy command. */
343 memset(&hints, 0, sizeof(hints));
344 hints.ai_family = family;
345 hints.ai_socktype = SOCK_STREAM;
346 snprintf(strport, sizeof strport, "%u", port);
347 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
348 fatal("%s: %.100s: %s", __progname, host,
349 gai_strerror(gaierr));
352 * Try to connect several times. On some machines, the first time
353 * will sometimes fail. In general socket code appears to behave
354 * quite magically on many machines.
356 for (attempt = 0; ;) {
358 debug("Trying again...");
360 /* Loop through addresses for this host, and try each one in
361 sequence until the connection succeeds. */
362 for (ai = aitop; ai; ai = ai->ai_next) {
363 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
365 if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
366 ntop, sizeof(ntop), strport, sizeof(strport),
367 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
368 error("ssh_connect: getnameinfo failed");
371 debug("Connecting to %.200s [%.100s] port %s.",
372 host, ntop, strport);
374 /* Create a socket for connecting. */
375 sock = ssh_create_socket(needpriv, ai);
377 /* Any error is already output */
380 if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
381 options.connection_timeout) >= 0) {
382 /* Successful connection. */
383 memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
386 if (errno == ECONNREFUSED)
388 debug("connect to address %s port %s: %s",
389 ntop, strport, strerror(errno));
391 * Close the failed socket; there appear to
392 * be some problems when reusing a socket for
393 * which connect() has already returned an
400 break; /* Successful connection. */
403 if (attempt >= connection_attempts)
405 /* Sleep a moment before retrying. */
411 /* Return failure if we didn't get a successful connection. */
412 if (attempt >= connection_attempts) {
413 logit("ssh: connect to host %s port %s: %s",
414 host, strport, strerror(errno));
415 return full_failure ? ECONNABORTED : ECONNREFUSED;
418 debug("Connection established.");
420 /* Set keepalives if requested. */
421 if (options.keepalives &&
422 setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
424 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
426 /* Set the connection. */
427 packet_set_connection(sock, sock);
433 * Waits for the server identification string, and sends our own
434 * identification string.
437 ssh_exchange_identification(void)
439 char buf[256], remote_version[256]; /* must be same size! */
440 int remote_major, remote_minor, i, mismatch;
441 int connection_in = packet_get_connection_in();
442 int connection_out = packet_get_connection_out();
443 int minor1 = PROTOCOL_MINOR_1;
445 /* Read other side\'s version identification. */
447 for (i = 0; i < sizeof(buf) - 1; i++) {
448 int len = atomicio(read, connection_in, &buf[i], 1);
450 fatal("ssh_exchange_identification: read: %.100s", strerror(errno));
452 fatal("ssh_exchange_identification: Connection closed by remote host");
453 if (buf[i] == '\r') {
456 continue; /**XXX wait for \n */
458 if (buf[i] == '\n') {
463 buf[sizeof(buf) - 1] = 0;
464 if (strncmp(buf, "SSH-", 4) == 0)
466 debug("ssh_exchange_identification: %s", buf);
468 server_version_string = xstrdup(buf);
471 * Check that the versions match. In future this might accept
472 * several versions and set appropriate flags to handle them.
474 if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
475 &remote_major, &remote_minor, remote_version) != 3)
476 fatal("Bad remote protocol version identification: '%.100s'", buf);
477 debug("Remote protocol version %d.%d, remote software version %.100s",
478 remote_major, remote_minor, remote_version);
480 compat_datafellows(remote_version);
483 switch (remote_major) {
485 if (remote_minor == 99 &&
486 (options.protocol & SSH_PROTO_2) &&
487 !(options.protocol & SSH_PROTO_1_PREFERRED)) {
491 if (!(options.protocol & SSH_PROTO_1)) {
495 if (remote_minor < 3) {
496 fatal("Remote machine has too old SSH software version.");
497 } else if (remote_minor == 3 || remote_minor == 4) {
498 /* We speak 1.3, too. */
501 if (options.forward_agent) {
502 logit("Agent forwarding disabled for protocol 1.3");
503 options.forward_agent = 0;
508 if (options.protocol & SSH_PROTO_2) {
518 fatal("Protocol major versions differ: %d vs. %d",
519 (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
521 /* Send our own protocol version identification. */
522 snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
523 compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
524 compat20 ? PROTOCOL_MINOR_2 : minor1,
526 if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
527 fatal("write: %.100s", strerror(errno));
528 client_version_string = xstrdup(buf);
529 chop(client_version_string);
530 chop(server_version_string);
531 debug("Local version string %.100s", client_version_string);
534 /* defaults to 'no' */
536 confirm(const char *prompt)
538 const char *msg, *again = "Please type 'yes' or 'no': ";
542 if (options.batch_mode)
544 for (msg = prompt;;msg = again) {
545 p = read_passphrase(msg, RP_ECHO);
547 (p[0] == '\0') || (p[0] == '\n') ||
548 strncasecmp(p, "no", 2) == 0)
550 if (p && strncasecmp(p, "yes", 3) == 0)
560 * check whether the supplied host key is valid, return -1 if the key
561 * is not valid. the user_hostfile will not be updated if 'readonly' is true.
564 check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
565 int readonly, const char *user_hostfile, const char *system_hostfile)
568 char *type = key_type(host_key);
570 char hostline[1000], *hostp, *fp;
571 HostStatus host_status;
572 HostStatus ip_status;
573 int local = 0, host_ip_differ = 0;
575 char ntop[NI_MAXHOST];
577 int len, host_line, ip_line;
578 const char *host_file = NULL, *ip_file = NULL;
581 * Force accepting of the host key for loopback/localhost. The
582 * problem is that if the home directory is NFS-mounted to multiple
583 * machines, localhost will refer to a different machine in each of
584 * them, and the user will get bogus HOST_CHANGED warnings. This
585 * essentially disables host authentication for localhost; however,
586 * this is probably not a real problem.
588 /** hostaddr == 0! */
589 switch (hostaddr->sa_family) {
591 local = (ntohl(((struct sockaddr_in *)hostaddr)->
592 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
593 salen = sizeof(struct sockaddr_in);
596 local = IN6_IS_ADDR_LOOPBACK(
597 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
598 salen = sizeof(struct sockaddr_in6);
602 salen = sizeof(struct sockaddr_storage);
605 if (options.no_host_authentication_for_localhost == 1 && local &&
606 options.host_key_alias == NULL) {
607 debug("Forcing accepting of host key for "
608 "loopback/localhost.");
613 * We don't have the remote ip-address for connections
614 * using a proxy command
616 if (options.proxy_command == NULL) {
617 if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
618 NULL, 0, NI_NUMERICHOST) != 0)
619 fatal("check_host_key: getnameinfo failed");
622 ip = xstrdup("<no hostip for proxy command>");
625 * Turn off check_host_ip if the connection is to localhost, via proxy
626 * command or if we don't have a hostname to compare with
628 if (options.check_host_ip &&
629 (local || strcmp(host, ip) == 0 || options.proxy_command != NULL))
630 options.check_host_ip = 0;
633 * Allow the user to record the key under a different name. This is
634 * useful for ssh tunneling over forwarded connections or if you run
635 * multiple sshd's on different ports on the same machine.
637 if (options.host_key_alias != NULL) {
638 host = options.host_key_alias;
639 debug("using hostkeyalias: %s", host);
643 * Store the host key from the known host file in here so that we can
644 * compare it with the key for the IP address.
646 file_key = key_new(host_key->type);
649 * Check if the host key is present in the user\'s list of known
650 * hosts or in the systemwide list.
652 host_file = user_hostfile;
653 host_status = check_host_in_hostfile(host_file, host, host_key,
654 file_key, &host_line);
655 if (host_status == HOST_NEW) {
656 host_file = system_hostfile;
657 host_status = check_host_in_hostfile(host_file, host, host_key,
658 file_key, &host_line);
661 * Also perform check for the ip address, skip the check if we are
662 * localhost or the hostname was an ip address to begin with
664 if (options.check_host_ip) {
665 Key *ip_key = key_new(host_key->type);
667 ip_file = user_hostfile;
668 ip_status = check_host_in_hostfile(ip_file, ip, host_key,
670 if (ip_status == HOST_NEW) {
671 ip_file = system_hostfile;
672 ip_status = check_host_in_hostfile(ip_file, ip,
673 host_key, ip_key, &ip_line);
675 if (host_status == HOST_CHANGED &&
676 (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
681 ip_status = host_status;
685 switch (host_status) {
687 /* The host is known and the key matches. */
688 debug("Host '%.200s' is known and matches the %s host key.",
690 debug("Found key in %s:%d", host_file, host_line);
691 if (options.check_host_ip && ip_status == HOST_NEW) {
693 logit("%s host key for IP address "
694 "'%.128s' not in list of known hosts.",
696 else if (!add_host_to_hostfile(user_hostfile, ip,
698 logit("Failed to add the %s host key for IP "
699 "address '%.128s' to the list of known "
700 "hosts (%.30s).", type, ip, user_hostfile);
702 logit("Warning: Permanently added the %s host "
703 "key for IP address '%.128s' to the list "
704 "of known hosts.", type, ip);
710 /* The host is new. */
711 if (options.strict_host_key_checking == 1) {
713 * User has requested strict host key checking. We
714 * will not add the host key automatically. The only
715 * alternative left is to abort.
717 error("No %s host key is known for %.200s and you "
718 "have requested strict checking.", type, host);
720 } else if (options.strict_host_key_checking == 2) {
721 char msg1[1024], msg2[1024];
723 if (show_other_keys(host, host_key))
724 snprintf(msg1, sizeof(msg1),
725 "\nbut keys of different type are already"
726 " known for this host.");
728 snprintf(msg1, sizeof(msg1), ".");
730 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
733 if (options.verify_host_key_dns) {
734 if (verified_host_key_dns)
735 snprintf(msg2, sizeof(msg2),
736 "Matching host key fingerprint"
739 snprintf(msg2, sizeof(msg2),
740 "No matching host key fingerprint"
744 snprintf(msg, sizeof(msg),
745 "The authenticity of host '%.200s (%s)' can't be "
747 "%s key fingerprint is %s.\n%s"
748 "Are you sure you want to continue connecting "
750 host, ip, msg1, type, fp, msg2);
755 if (options.check_host_ip && ip_status == HOST_NEW) {
756 snprintf(hostline, sizeof(hostline), "%s,%s", host, ip);
762 * If not in strict mode, add the key automatically to the
763 * local known_hosts file.
765 if (!add_host_to_hostfile(user_hostfile, hostp, host_key))
766 logit("Failed to add the host to the list of known "
767 "hosts (%.500s).", user_hostfile);
769 logit("Warning: Permanently added '%.200s' (%s) to the "
770 "list of known hosts.", hostp, type);
773 if (options.check_host_ip && host_ip_differ) {
775 if (ip_status == HOST_NEW)
777 else if (ip_status == HOST_OK)
778 msg = "is unchanged";
780 msg = "has a different value";
781 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
782 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
783 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
784 error("The %s host key for %s has changed,", type, host);
785 error("and the key for the according IP address %s", ip);
786 error("%s. This could either mean that", msg);
787 error("DNS SPOOFING is happening or the IP address for the host");
788 error("and its host key have changed at the same time.");
789 if (ip_status != HOST_NEW)
790 error("Offending key for IP in %s:%d", ip_file, ip_line);
792 /* The host key has changed. */
793 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
794 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
795 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
796 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
797 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
798 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
799 error("It is also possible that the %s host key has just been changed.", type);
800 error("The fingerprint for the %s key sent by the remote host is\n%s.",
802 error("Please contact your system administrator.");
803 error("Add correct host key in %.100s to get rid of this message.",
805 error("Offending key in %s:%d", host_file, host_line);
809 * If strict host key checking is in use, the user will have
810 * to edit the key manually and we can only abort.
812 if (options.strict_host_key_checking) {
813 error("%s host key for %.200s has changed and you have "
814 "requested strict checking.", type, host);
819 * If strict host key checking has not been requested, allow
820 * the connection but without MITM-able authentication or
823 if (options.password_authentication) {
824 error("Password authentication is disabled to avoid "
825 "man-in-the-middle attacks.");
826 options.password_authentication = 0;
828 if (options.kbd_interactive_authentication) {
829 error("Keyboard-interactive authentication is disabled"
830 " to avoid man-in-the-middle attacks.");
831 options.kbd_interactive_authentication = 0;
832 options.challenge_response_authentication = 0;
834 if (options.challenge_response_authentication) {
835 error("Challenge/response authentication is disabled"
836 " to avoid man-in-the-middle attacks.");
837 options.challenge_response_authentication = 0;
839 if (options.forward_agent) {
840 error("Agent forwarding is disabled to avoid "
841 "man-in-the-middle attacks.");
842 options.forward_agent = 0;
844 if (options.forward_x11) {
845 error("X11 forwarding is disabled to avoid "
846 "man-in-the-middle attacks.");
847 options.forward_x11 = 0;
849 if (options.num_local_forwards > 0 ||
850 options.num_remote_forwards > 0) {
851 error("Port forwarding is disabled to avoid "
852 "man-in-the-middle attacks.");
853 options.num_local_forwards =
854 options.num_remote_forwards = 0;
857 * XXX Should permit the user to change to use the new id.
858 * This could be done by converting the host key to an
859 * identifying sentence, tell that the host identifies itself
860 * by that sentence, and ask the user if he/she whishes to
861 * accept the authentication.
865 fatal("internal error");
869 if (options.check_host_ip && host_status != HOST_CHANGED &&
870 ip_status == HOST_CHANGED) {
871 snprintf(msg, sizeof(msg),
872 "Warning: the %s host key for '%.200s' "
873 "differs from the key for the IP address '%.128s'"
874 "\nOffending key for IP in %s:%d",
875 type, host, ip, ip_file, ip_line);
876 if (host_status == HOST_OK) {
878 snprintf(msg + len, sizeof(msg) - len,
879 "\nMatching host key in %s:%d",
880 host_file, host_line);
882 if (options.strict_host_key_checking == 1) {
884 error("Exiting, you have requested strict checking.");
886 } else if (options.strict_host_key_checking == 2) {
887 strlcat(msg, "\nAre you sure you want "
888 "to continue connecting (yes/no)? ", sizeof(msg));
904 /* returns 0 if key verifies or -1 if key does NOT verify */
906 verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
911 if (options.verify_host_key_dns) {
912 switch(verify_host_key_dns(host, hostaddr, host_key)) {
917 verified_host_key_dns = 1;
920 case DNS_VERIFY_FAILED:
922 case DNS_VERIFY_ERROR:
925 debug3("bad return value from verify_host_key_dns");
931 /* return ok if the key can be found in an old keyfile */
932 if (stat(options.system_hostfile2, &st) == 0 ||
933 stat(options.user_hostfile2, &st) == 0) {
934 if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1,
935 options.user_hostfile2, options.system_hostfile2) == 0)
938 return check_host_key(host, hostaddr, host_key, /*readonly*/ 0,
939 options.user_hostfile, options.system_hostfile);
943 * Starts a dialog with the server, and authenticates the current user on the
944 * server. This does not need any extra privileges. The basic connection
945 * to the server must already have been established before this is called.
946 * If login fails, this function prints an error and never returns.
947 * This function does not require super-user privileges.
950 ssh_login(Sensitive *sensitive, const char *orighost,
951 struct sockaddr *hostaddr, struct passwd *pw)
954 char *server_user, *local_user;
956 local_user = xstrdup(pw->pw_name);
957 server_user = options.user ? options.user : local_user;
959 /* Convert the user-supplied hostname into all lowercase. */
960 host = xstrdup(orighost);
961 for (cp = host; *cp; cp++)
965 /* Exchange protocol version identification strings with the server. */
966 ssh_exchange_identification();
968 /* Put the connection into non-blocking mode. */
969 packet_set_nonblocking();
972 /* authenticate user */
974 ssh_kex2(host, hostaddr);
975 ssh_userauth2(local_user, server_user, host, sensitive);
977 ssh_kex(host, hostaddr);
978 ssh_userauth1(local_user, server_user, host, sensitive);
983 ssh_put_password(char *password)
988 if (datafellows & SSH_BUG_PASSWORDPAD) {
989 packet_put_cstring(password);
992 size = roundup(strlen(password) + 1, 32);
993 padded = xmalloc(size);
994 memset(padded, 0, size);
995 strlcpy(padded, password, size);
996 packet_put_string(padded, size);
997 memset(padded, 0, size);
1002 show_key_from_file(const char *file, const char *host, int keytype)
1008 found = key_new(keytype);
1009 if ((ret = lookup_key_in_hostfile_by_type(file, host,
1010 keytype, found, &line))) {
1011 fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
1012 logit("WARNING: %s key found for host %s\n"
1014 "%s key fingerprint %s.",
1015 key_type(found), host, file, line,
1016 key_type(found), fp);
1023 /* print all known host keys for a given host, but skip keys of given type */
1025 show_other_keys(const char *host, Key *key)
1027 int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
1030 for (i = 0; type[i] != -1; i++) {
1031 if (type[i] == key->type)
1033 if (type[i] != KEY_RSA1 &&
1034 show_key_from_file(options.user_hostfile2, host, type[i])) {
1038 if (type[i] != KEY_RSA1 &&
1039 show_key_from_file(options.system_hostfile2, host, type[i])) {
1043 if (show_key_from_file(options.user_hostfile, host, type[i])) {
1047 if (show_key_from_file(options.system_hostfile, host, type[i])) {
1051 debug2("no key of type %d for host %s", type[i], host);