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 1.148 2003/09/18 07:52:54 markus 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));
285 /* Should not occur */
286 fatal("Bogus return (%d) from select()", rc);
294 * Opens a TCP/IP connection to the remote server on the given host.
295 * The address of the remote host will be returned in hostaddr.
296 * If port is 0, the default port will be used. If needpriv is true,
297 * a privileged port will be allocated to make the connection.
298 * This requires super-user privileges if needpriv is true.
299 * Connection_attempts specifies the maximum number of tries (one per
300 * second). If proxy_command is non-NULL, it specifies the command (with %h
301 * and %p substituted for host and port, respectively) to use to contact
305 * ECONNREFUSED if we got a "Connection Refused" by the peer on any address
306 * ECONNABORTED if we failed without a "Connection refused"
307 * Suitable error messages for the connection failure will already have been
311 ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
312 u_short port, int family, int connection_attempts,
313 int needpriv, const char *proxy_command)
317 int sock = -1, attempt;
318 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
319 struct addrinfo hints, *ai, *aitop;
322 * Did we get only other errors than "Connection refused" (which
323 * should block fallback to rsh and similar), or did we get at least
324 * one "Connection refused"?
326 int full_failure = 1;
328 debug2("ssh_connect: needpriv %d", needpriv);
330 /* Get default port if port has not been set. */
332 sp = getservbyname(SSH_SERVICE_NAME, "tcp");
334 port = ntohs(sp->s_port);
336 port = SSH_DEFAULT_PORT;
338 /* If a proxy command is given, connect using it. */
339 if (proxy_command != NULL)
340 return ssh_proxy_connect(host, port, proxy_command);
342 /* No proxy command. */
344 memset(&hints, 0, sizeof(hints));
345 hints.ai_family = family;
346 hints.ai_socktype = SOCK_STREAM;
347 snprintf(strport, sizeof strport, "%u", port);
348 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0)
349 fatal("%s: %.100s: %s", __progname, host,
350 gai_strerror(gaierr));
353 * Try to connect several times. On some machines, the first time
354 * will sometimes fail. In general socket code appears to behave
355 * quite magically on many machines.
357 for (attempt = 0; ;) {
359 debug("Trying again...");
361 /* Loop through addresses for this host, and try each one in
362 sequence until the connection succeeds. */
363 for (ai = aitop; ai; ai = ai->ai_next) {
364 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
366 if (getnameinfo(ai->ai_addr, ai->ai_addrlen,
367 ntop, sizeof(ntop), strport, sizeof(strport),
368 NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
369 error("ssh_connect: getnameinfo failed");
372 debug("Connecting to %.200s [%.100s] port %s.",
373 host, ntop, strport);
375 /* Create a socket for connecting. */
376 sock = ssh_create_socket(needpriv, ai);
378 /* Any error is already output */
381 if (timeout_connect(sock, ai->ai_addr, ai->ai_addrlen,
382 options.connection_timeout) >= 0) {
383 /* Successful connection. */
384 memcpy(hostaddr, ai->ai_addr, ai->ai_addrlen);
387 if (errno == ECONNREFUSED)
389 debug("connect to address %s port %s: %s",
390 ntop, strport, strerror(errno));
392 * Close the failed socket; there appear to
393 * be some problems when reusing a socket for
394 * which connect() has already returned an
401 break; /* Successful connection. */
404 if (attempt >= connection_attempts)
406 /* Sleep a moment before retrying. */
412 /* Return failure if we didn't get a successful connection. */
413 if (attempt >= connection_attempts) {
414 logit("ssh: connect to host %s port %s: %s",
415 host, strport, strerror(errno));
416 return full_failure ? ECONNABORTED : ECONNREFUSED;
419 debug("Connection established.");
421 /* Set keepalives if requested. */
422 if (options.keepalives &&
423 setsockopt(sock, SOL_SOCKET, SO_KEEPALIVE, (void *)&on,
425 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
427 /* Set the connection. */
428 packet_set_connection(sock, sock);
434 * Waits for the server identification string, and sends our own
435 * identification string.
438 ssh_exchange_identification(void)
440 char buf[256], remote_version[256]; /* must be same size! */
441 int remote_major, remote_minor, i, mismatch;
442 int connection_in = packet_get_connection_in();
443 int connection_out = packet_get_connection_out();
444 int minor1 = PROTOCOL_MINOR_1;
446 /* Read other side\'s version identification. */
448 for (i = 0; i < sizeof(buf) - 1; i++) {
449 int len = atomicio(read, connection_in, &buf[i], 1);
451 fatal("ssh_exchange_identification: read: %.100s", strerror(errno));
453 fatal("ssh_exchange_identification: Connection closed by remote host");
454 if (buf[i] == '\r') {
457 continue; /**XXX wait for \n */
459 if (buf[i] == '\n') {
464 buf[sizeof(buf) - 1] = 0;
465 if (strncmp(buf, "SSH-", 4) == 0)
467 debug("ssh_exchange_identification: %s", buf);
469 server_version_string = xstrdup(buf);
472 * Check that the versions match. In future this might accept
473 * several versions and set appropriate flags to handle them.
475 if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
476 &remote_major, &remote_minor, remote_version) != 3)
477 fatal("Bad remote protocol version identification: '%.100s'", buf);
478 debug("Remote protocol version %d.%d, remote software version %.100s",
479 remote_major, remote_minor, remote_version);
481 compat_datafellows(remote_version);
484 switch (remote_major) {
486 if (remote_minor == 99 &&
487 (options.protocol & SSH_PROTO_2) &&
488 !(options.protocol & SSH_PROTO_1_PREFERRED)) {
492 if (!(options.protocol & SSH_PROTO_1)) {
496 if (remote_minor < 3) {
497 fatal("Remote machine has too old SSH software version.");
498 } else if (remote_minor == 3 || remote_minor == 4) {
499 /* We speak 1.3, too. */
502 if (options.forward_agent) {
503 logit("Agent forwarding disabled for protocol 1.3");
504 options.forward_agent = 0;
509 if (options.protocol & SSH_PROTO_2) {
519 fatal("Protocol major versions differ: %d vs. %d",
520 (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
522 /* Send our own protocol version identification. */
523 snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
524 compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
525 compat20 ? PROTOCOL_MINOR_2 : minor1,
527 if (atomicio(vwrite, connection_out, buf, strlen(buf)) != strlen(buf))
528 fatal("write: %.100s", strerror(errno));
529 client_version_string = xstrdup(buf);
530 chop(client_version_string);
531 chop(server_version_string);
532 debug("Local version string %.100s", client_version_string);
535 /* defaults to 'no' */
537 confirm(const char *prompt)
539 const char *msg, *again = "Please type 'yes' or 'no': ";
543 if (options.batch_mode)
545 for (msg = prompt;;msg = again) {
546 p = read_passphrase(msg, RP_ECHO);
548 (p[0] == '\0') || (p[0] == '\n') ||
549 strncasecmp(p, "no", 2) == 0)
551 if (p && strncasecmp(p, "yes", 3) == 0)
561 * check whether the supplied host key is valid, return -1 if the key
562 * is not valid. the user_hostfile will not be updated if 'readonly' is true.
565 check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
566 int readonly, const char *user_hostfile, const char *system_hostfile)
569 char *type = key_type(host_key);
571 char hostline[1000], *hostp, *fp;
572 HostStatus host_status;
573 HostStatus ip_status;
574 int local = 0, host_ip_differ = 0;
576 char ntop[NI_MAXHOST];
578 int len, host_line, ip_line;
579 const char *host_file = NULL, *ip_file = NULL;
582 * Force accepting of the host key for loopback/localhost. The
583 * problem is that if the home directory is NFS-mounted to multiple
584 * machines, localhost will refer to a different machine in each of
585 * them, and the user will get bogus HOST_CHANGED warnings. This
586 * essentially disables host authentication for localhost; however,
587 * this is probably not a real problem.
589 /** hostaddr == 0! */
590 switch (hostaddr->sa_family) {
592 local = (ntohl(((struct sockaddr_in *)hostaddr)->
593 sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
594 salen = sizeof(struct sockaddr_in);
597 local = IN6_IS_ADDR_LOOPBACK(
598 &(((struct sockaddr_in6 *)hostaddr)->sin6_addr));
599 salen = sizeof(struct sockaddr_in6);
603 salen = sizeof(struct sockaddr_storage);
606 if (options.no_host_authentication_for_localhost == 1 && local &&
607 options.host_key_alias == NULL) {
608 debug("Forcing accepting of host key for "
609 "loopback/localhost.");
614 * We don't have the remote ip-address for connections
615 * using a proxy command
617 if (options.proxy_command == NULL) {
618 if (getnameinfo(hostaddr, salen, ntop, sizeof(ntop),
619 NULL, 0, NI_NUMERICHOST) != 0)
620 fatal("check_host_key: getnameinfo failed");
623 ip = xstrdup("<no hostip for proxy command>");
626 * Turn off check_host_ip if the connection is to localhost, via proxy
627 * command or if we don't have a hostname to compare with
629 if (options.check_host_ip &&
630 (local || strcmp(host, ip) == 0 || options.proxy_command != NULL))
631 options.check_host_ip = 0;
634 * Allow the user to record the key under a different name. This is
635 * useful for ssh tunneling over forwarded connections or if you run
636 * multiple sshd's on different ports on the same machine.
638 if (options.host_key_alias != NULL) {
639 host = options.host_key_alias;
640 debug("using hostkeyalias: %s", host);
644 * Store the host key from the known host file in here so that we can
645 * compare it with the key for the IP address.
647 file_key = key_new(host_key->type);
650 * Check if the host key is present in the user\'s list of known
651 * hosts or in the systemwide list.
653 host_file = user_hostfile;
654 host_status = check_host_in_hostfile(host_file, host, host_key,
655 file_key, &host_line);
656 if (host_status == HOST_NEW) {
657 host_file = system_hostfile;
658 host_status = check_host_in_hostfile(host_file, host, host_key,
659 file_key, &host_line);
662 * Also perform check for the ip address, skip the check if we are
663 * localhost or the hostname was an ip address to begin with
665 if (options.check_host_ip) {
666 Key *ip_key = key_new(host_key->type);
668 ip_file = user_hostfile;
669 ip_status = check_host_in_hostfile(ip_file, ip, host_key,
671 if (ip_status == HOST_NEW) {
672 ip_file = system_hostfile;
673 ip_status = check_host_in_hostfile(ip_file, ip,
674 host_key, ip_key, &ip_line);
676 if (host_status == HOST_CHANGED &&
677 (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
682 ip_status = host_status;
686 switch (host_status) {
688 /* The host is known and the key matches. */
689 debug("Host '%.200s' is known and matches the %s host key.",
691 debug("Found key in %s:%d", host_file, host_line);
692 if (options.check_host_ip && ip_status == HOST_NEW) {
694 logit("%s host key for IP address "
695 "'%.128s' not in list of known hosts.",
697 else if (!add_host_to_hostfile(user_hostfile, ip,
699 logit("Failed to add the %s host key for IP "
700 "address '%.128s' to the list of known "
701 "hosts (%.30s).", type, ip, user_hostfile);
703 logit("Warning: Permanently added the %s host "
704 "key for IP address '%.128s' to the list "
705 "of known hosts.", type, ip);
711 /* The host is new. */
712 if (options.strict_host_key_checking == 1) {
714 * User has requested strict host key checking. We
715 * will not add the host key automatically. The only
716 * alternative left is to abort.
718 error("No %s host key is known for %.200s and you "
719 "have requested strict checking.", type, host);
721 } else if (options.strict_host_key_checking == 2) {
722 char msg1[1024], msg2[1024];
724 if (show_other_keys(host, host_key))
725 snprintf(msg1, sizeof(msg1),
726 "\nbut keys of different type are already"
727 " known for this host.");
729 snprintf(msg1, sizeof(msg1), ".");
731 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
734 if (options.verify_host_key_dns) {
735 if (verified_host_key_dns)
736 snprintf(msg2, sizeof(msg2),
737 "Matching host key fingerprint"
740 snprintf(msg2, sizeof(msg2),
741 "No matching host key fingerprint"
745 snprintf(msg, sizeof(msg),
746 "The authenticity of host '%.200s (%s)' can't be "
748 "%s key fingerprint is %s.\n%s"
749 "Are you sure you want to continue connecting "
751 host, ip, msg1, type, fp, msg2);
756 if (options.check_host_ip && ip_status == HOST_NEW) {
757 snprintf(hostline, sizeof(hostline), "%s,%s", host, ip);
763 * If not in strict mode, add the key automatically to the
764 * local known_hosts file.
766 if (!add_host_to_hostfile(user_hostfile, hostp, host_key))
767 logit("Failed to add the host to the list of known "
768 "hosts (%.500s).", user_hostfile);
770 logit("Warning: Permanently added '%.200s' (%s) to the "
771 "list of known hosts.", hostp, type);
774 if (options.check_host_ip && host_ip_differ) {
776 if (ip_status == HOST_NEW)
778 else if (ip_status == HOST_OK)
779 msg = "is unchanged";
781 msg = "has a different value";
782 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
783 error("@ WARNING: POSSIBLE DNS SPOOFING DETECTED! @");
784 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
785 error("The %s host key for %s has changed,", type, host);
786 error("and the key for the according IP address %s", ip);
787 error("%s. This could either mean that", msg);
788 error("DNS SPOOFING is happening or the IP address for the host");
789 error("and its host key have changed at the same time.");
790 if (ip_status != HOST_NEW)
791 error("Offending key for IP in %s:%d", ip_file, ip_line);
793 /* The host key has changed. */
794 fp = key_fingerprint(host_key, SSH_FP_MD5, SSH_FP_HEX);
795 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
796 error("@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @");
797 error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
798 error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
799 error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
800 error("It is also possible that the %s host key has just been changed.", type);
801 error("The fingerprint for the %s key sent by the remote host is\n%s.",
803 error("Please contact your system administrator.");
804 error("Add correct host key in %.100s to get rid of this message.",
806 error("Offending key in %s:%d", host_file, host_line);
810 * If strict host key checking is in use, the user will have
811 * to edit the key manually and we can only abort.
813 if (options.strict_host_key_checking) {
814 error("%s host key for %.200s has changed and you have "
815 "requested strict checking.", type, host);
820 * If strict host key checking has not been requested, allow
821 * the connection but without MITM-able authentication or
824 if (options.password_authentication) {
825 error("Password authentication is disabled to avoid "
826 "man-in-the-middle attacks.");
827 options.password_authentication = 0;
829 if (options.kbd_interactive_authentication) {
830 error("Keyboard-interactive authentication is disabled"
831 " to avoid man-in-the-middle attacks.");
832 options.kbd_interactive_authentication = 0;
833 options.challenge_response_authentication = 0;
835 if (options.challenge_response_authentication) {
836 error("Challenge/response authentication is disabled"
837 " to avoid man-in-the-middle attacks.");
838 options.challenge_response_authentication = 0;
840 if (options.forward_agent) {
841 error("Agent forwarding is disabled to avoid "
842 "man-in-the-middle attacks.");
843 options.forward_agent = 0;
845 if (options.forward_x11) {
846 error("X11 forwarding is disabled to avoid "
847 "man-in-the-middle attacks.");
848 options.forward_x11 = 0;
850 if (options.num_local_forwards > 0 ||
851 options.num_remote_forwards > 0) {
852 error("Port forwarding is disabled to avoid "
853 "man-in-the-middle attacks.");
854 options.num_local_forwards =
855 options.num_remote_forwards = 0;
858 * XXX Should permit the user to change to use the new id.
859 * This could be done by converting the host key to an
860 * identifying sentence, tell that the host identifies itself
861 * by that sentence, and ask the user if he/she whishes to
862 * accept the authentication.
866 fatal("internal error");
870 if (options.check_host_ip && host_status != HOST_CHANGED &&
871 ip_status == HOST_CHANGED) {
872 snprintf(msg, sizeof(msg),
873 "Warning: the %s host key for '%.200s' "
874 "differs from the key for the IP address '%.128s'"
875 "\nOffending key for IP in %s:%d",
876 type, host, ip, ip_file, ip_line);
877 if (host_status == HOST_OK) {
879 snprintf(msg + len, sizeof(msg) - len,
880 "\nMatching host key in %s:%d",
881 host_file, host_line);
883 if (options.strict_host_key_checking == 1) {
885 error("Exiting, you have requested strict checking.");
887 } else if (options.strict_host_key_checking == 2) {
888 strlcat(msg, "\nAre you sure you want "
889 "to continue connecting (yes/no)? ", sizeof(msg));
905 /* returns 0 if key verifies or -1 if key does NOT verify */
907 verify_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
912 if (options.verify_host_key_dns) {
913 switch(verify_host_key_dns(host, hostaddr, host_key)) {
918 verified_host_key_dns = 1;
921 case DNS_VERIFY_FAILED:
923 case DNS_VERIFY_ERROR:
926 debug3("bad return value from verify_host_key_dns");
932 /* return ok if the key can be found in an old keyfile */
933 if (stat(options.system_hostfile2, &st) == 0 ||
934 stat(options.user_hostfile2, &st) == 0) {
935 if (check_host_key(host, hostaddr, host_key, /*readonly*/ 1,
936 options.user_hostfile2, options.system_hostfile2) == 0)
939 return check_host_key(host, hostaddr, host_key, /*readonly*/ 0,
940 options.user_hostfile, options.system_hostfile);
944 * Starts a dialog with the server, and authenticates the current user on the
945 * server. This does not need any extra privileges. The basic connection
946 * to the server must already have been established before this is called.
947 * If login fails, this function prints an error and never returns.
948 * This function does not require super-user privileges.
951 ssh_login(Sensitive *sensitive, const char *orighost,
952 struct sockaddr *hostaddr, struct passwd *pw)
955 char *server_user, *local_user;
957 local_user = xstrdup(pw->pw_name);
958 server_user = options.user ? options.user : local_user;
960 /* Convert the user-supplied hostname into all lowercase. */
961 host = xstrdup(orighost);
962 for (cp = host; *cp; cp++)
966 /* Exchange protocol version identification strings with the server. */
967 ssh_exchange_identification();
969 /* Put the connection into non-blocking mode. */
970 packet_set_nonblocking();
973 /* authenticate user */
975 ssh_kex2(host, hostaddr);
976 ssh_userauth2(local_user, server_user, host, sensitive);
978 ssh_kex(host, hostaddr);
979 ssh_userauth1(local_user, server_user, host, sensitive);
984 ssh_put_password(char *password)
989 if (datafellows & SSH_BUG_PASSWORDPAD) {
990 packet_put_cstring(password);
993 size = roundup(strlen(password) + 1, 32);
994 padded = xmalloc(size);
995 memset(padded, 0, size);
996 strlcpy(padded, password, size);
997 packet_put_string(padded, size);
998 memset(padded, 0, size);
1003 show_key_from_file(const char *file, const char *host, int keytype)
1009 found = key_new(keytype);
1010 if ((ret = lookup_key_in_hostfile_by_type(file, host,
1011 keytype, found, &line))) {
1012 fp = key_fingerprint(found, SSH_FP_MD5, SSH_FP_HEX);
1013 logit("WARNING: %s key found for host %s\n"
1015 "%s key fingerprint %s.",
1016 key_type(found), host, file, line,
1017 key_type(found), fp);
1024 /* print all known host keys for a given host, but skip keys of given type */
1026 show_other_keys(const char *host, Key *key)
1028 int type[] = { KEY_RSA1, KEY_RSA, KEY_DSA, -1};
1031 for (i = 0; type[i] != -1; i++) {
1032 if (type[i] == key->type)
1034 if (type[i] != KEY_RSA1 &&
1035 show_key_from_file(options.user_hostfile2, host, type[i])) {
1039 if (type[i] != KEY_RSA1 &&
1040 show_key_from_file(options.system_hostfile2, host, type[i])) {
1044 if (show_key_from_file(options.user_hostfile, host, type[i])) {
1048 if (show_key_from_file(options.system_hostfile, host, type[i])) {
1052 debug2("no key of type %d for host %s", type[i], host);