2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Ssh client program. This program can be used to log into a remote machine.
6 * The software supports strong authentication, encryption, and forwarding
7 * of X11, TCP/IP, and authentication connections.
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".
15 * Copyright (c) 1999 Niels Provos. All rights reserved.
17 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
18 * in Canada (German citizen).
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
23 * 1. Redistributions of source code must retain the above copyright
24 * notice, this list of conditions and the following disclaimer.
25 * 2. Redistributions in binary form must reproduce the above copyright
26 * notice, this list of conditions and the following disclaimer in the
27 * documentation and/or other materials provided with the distribution.
29 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
30 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
31 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
32 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
33 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
34 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
35 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
36 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
37 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
38 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
42 RCSID("$OpenBSD: ssh.c,v 1.95 2001/02/11 12:59:25 markus Exp $");
44 #include <openssl/evp.h>
45 #include <openssl/err.h>
60 #include "pathnames.h"
61 #include "clientloop.h"
64 #include "sshconnect.h"
65 #include "tildexpand.h"
71 #ifdef HAVE___PROGNAME
72 extern char *__progname;
77 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
78 Default value is AF_UNSPEC means both IPv4 and IPv6. */
80 int IPv4or6 = AF_INET;
82 int IPv4or6 = AF_UNSPEC;
85 /* Flag indicating whether debug mode is on. This can be set on the command line. */
88 /* Flag indicating whether a tty should be allocated */
91 int force_tty_flag = 0;
93 /* don't exec a shell */
94 int no_shell_flag = 0;
97 * Flag indicating that nothing should be read from stdin. This can be set
98 * on the command line.
100 int stdin_null_flag = 0;
103 * Flag indicating that ssh should fork after authentication. This is useful
104 * so that the pasphrase can be entered manually, and then ssh goes to the
107 int fork_after_authentication_flag = 0;
110 * General data structure for command line options and options configurable
111 * in configuration files. See readconf.h.
116 * Name of the host we are connecting to. This is the name given on the
117 * command line, or the HostName specified for the user-supplied name in a
118 * configuration file.
122 /* socket address the host resolves to */
123 struct sockaddr_storage hostaddr;
126 * Flag to indicate that we have received a window change signal which has
127 * not yet been processed. This will cause a message indicating the new
128 * window size to be sent to the server a little later. This is volatile
129 * because this is updated in a signal handler.
131 volatile int received_window_change_signal = 0;
133 /* Flag indicating whether we have a valid host private key loaded. */
134 int host_private_key_loaded = 0;
136 /* Host private key. */
137 RSA *host_private_key = NULL;
139 /* Original real UID. */
140 uid_t original_real_uid;
142 /* command to be executed */
145 /* Should we execute a command or invoke a subsystem? */
146 int subsystem_flag = 0;
148 /* Prints a help message to the user. This function never returns. */
153 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
154 fprintf(stderr, "Options:\n");
155 fprintf(stderr, " -l user Log in using this user name.\n");
156 fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n");
157 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
158 fprintf(stderr, " -a Disable authentication agent forwarding.\n");
160 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
162 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
163 fprintf(stderr, " -x Disable X11 connection forwarding.\n");
164 fprintf(stderr, " -i file Identity for RSA authentication (default: ~/.ssh/identity).\n");
165 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
166 fprintf(stderr, " -T Do not allocate a tty.\n");
167 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
168 fprintf(stderr, " Multiple -v increases verbosity.\n");
169 fprintf(stderr, " -V Display version number only.\n");
170 fprintf(stderr, " -P Don't allocate a privileged port.\n");
171 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
172 fprintf(stderr, " -f Fork into background after authentication.\n");
173 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
175 fprintf(stderr, " -c cipher Select encryption algorithm: "
178 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
179 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
180 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
181 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
182 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
183 fprintf(stderr, " -C Enable compression.\n");
184 fprintf(stderr, " -N Do not execute a shell or command.\n");
185 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
186 fprintf(stderr, " -1 Force protocol version 1.\n");
187 fprintf(stderr, " -2 Force protocol version 2.\n");
188 fprintf(stderr, " -4 Use IPv4 only.\n");
189 fprintf(stderr, " -6 Use IPv6 only.\n");
190 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
191 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
196 * Connects to the given host using rsh (or prints an error message and exits
197 * if rsh is not available). This function never returns.
200 rsh_connect(char *host, char *user, Buffer * command)
205 log("Using rsh. WARNING: Connection will not be encrypted.");
206 /* Build argument list for rsh. */
208 args[i++] = _PATH_RSH;
209 /* host may have to come after user on some systems */
215 if (buffer_len(command) > 0) {
216 buffer_append(command, "\0", 1);
217 args[i++] = buffer_ptr(command);
221 for (i = 0; args[i]; i++) {
223 fprintf(stderr, " ");
224 fprintf(stderr, "%s", args[i]);
226 fprintf(stderr, "\n");
228 execv(_PATH_RSH, args);
233 int ssh_session(void);
234 int ssh_session2(void);
235 int guess_identity_file_type(const char *filename);
238 * Main program for the ssh client.
241 main(int ac, char **av)
243 int i, opt, optind, exit_status, ok;
244 u_short fwd_port, fwd_host_port;
245 char *optarg, *cp, buf[256];
247 struct passwd *pw, pwcopy;
249 uid_t original_effective_uid;
251 __progname = get_progname(av[0]);
255 * Save the original real uid. It will be needed later (uid-swapping
256 * may clobber the real uid).
258 original_real_uid = getuid();
259 original_effective_uid = geteuid();
261 #ifdef HAVE_SETRLIMIT
262 /* If we are installed setuid root be careful to not drop core. */
263 if (original_real_uid != original_effective_uid) {
265 rlim.rlim_cur = rlim.rlim_max = 0;
266 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
267 fatal("setrlimit failed: %.100s", strerror(errno));
271 * Use uid-swapping to give up root privileges for the duration of
272 * option processing. We will re-instantiate the rights when we are
273 * ready to create the privileged port, and will permanently drop
274 * them when the port has been created (actually, when the connection
275 * has been made, as we may need to create the port several times).
277 temporarily_use_uid(original_real_uid);
280 * Set our umask to something reasonable, as some files are created
281 * with the default umask. This will make them world-readable but
282 * writable only by the owner, which is ok for all files for which we
283 * don't set the modes explicitly.
287 /* Initialize option structure to indicate that no values have been set. */
288 initialize_options(&options);
290 /* Parse command-line arguments. */
293 for (optind = 1; optind < ac; optind++) {
294 if (av[optind][0] != '-') {
297 if ((cp = strchr(av[optind], '@'))) {
300 options.user = av[optind];
310 if (strchr("eilcmpLRo", opt)) { /* options with arguments */
311 optarg = av[optind] + 2;
312 if (strcmp(optarg, "") == 0) {
313 if (optind >= ac - 1)
315 optarg = av[++optind];
324 options.protocol = SSH_PROTO_1;
327 options.protocol = SSH_PROTO_2;
339 fork_after_authentication_flag = 1;
343 options.forward_x11 = 0;
346 options.forward_x11 = 1;
349 options.gateway_ports = 1;
352 options.use_privileged_port = 0;
355 options.forward_agent = 0;
358 options.forward_agent = 1;
362 options.kerberos_tgt_passing = 0;
363 options.afs_token_passing = 0;
367 if (stat(optarg, &st) < 0) {
368 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
372 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
373 fatal("Too many identity files specified (max %d)",
374 SSH_MAX_IDENTITY_FILES);
375 options.identity_files[options.num_identity_files++] = xstrdup(optarg);
383 if (0 == debug_flag) {
385 options.log_level = SYSLOG_LEVEL_DEBUG1;
386 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
390 fatal("Too high debugging level.\n");
394 fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n",
396 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
397 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2);
398 fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay());
403 options.log_level = SYSLOG_LEVEL_QUIET;
406 if (optarg[0] == '^' && optarg[2] == 0 &&
407 (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128)
408 options.escape_char = (u_char) optarg[1] & 31;
409 else if (strlen(optarg) == 1)
410 options.escape_char = (u_char) optarg[0];
411 else if (strcmp(optarg, "none") == 0)
412 options.escape_char = -2;
414 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
419 if (ciphers_valid(optarg)) {
421 options.ciphers = xstrdup(optarg);
422 options.cipher = SSH_CIPHER_ILLEGAL;
425 options.cipher = cipher_number(optarg);
426 if (options.cipher == -1) {
427 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
430 if (options.cipher == SSH_CIPHER_3DES) {
431 options.ciphers = "3des-cbc";
432 } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
433 options.ciphers = "blowfish-cbc";
435 options.ciphers = (char *)-1;
440 if (mac_valid(optarg))
441 options.macs = xstrdup(optarg);
443 fprintf(stderr, "Unknown mac type '%s'\n", optarg);
448 options.port = atoi(optarg);
451 options.user = optarg;
454 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
455 &fwd_host_port) != 3 &&
456 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
457 &fwd_host_port) != 3) {
458 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
462 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
465 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
466 &fwd_host_port) != 3 &&
467 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
468 &fwd_host_port) != 3) {
469 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
473 add_local_forward(&options, fwd_port, buf, fwd_host_port);
476 options.compression = 1;
487 if (process_config_line(&options, host ? host : "", optarg,
488 "command-line", 0, &dummy) != 0)
499 /* Check that we got a host name. */
503 SSLeay_add_all_algorithms();
504 ERR_load_crypto_strings();
506 /* Initialize the command to execute on remote host. */
507 buffer_init(&command);
510 * Save the command to execute on the remote host in a buffer. There
511 * is no limit on the length of the command, except by the maximum
512 * packet size. Also sets the tty flag if there is no command.
515 /* No command specified - execute shell on a tty. */
517 if (subsystem_flag) {
518 fprintf(stderr, "You must specify a subsystem to invoke.");
522 /* A command has been specified. Store it into the
524 for (i = optind; i < ac; i++) {
526 buffer_append(&command, " ", 1);
527 buffer_append(&command, av[i], strlen(av[i]));
531 /* Cannot fork to background if no command. */
532 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
533 fatal("Cannot fork into background without a command to execute.");
535 /* Allocate a tty by default if no command specified. */
536 if (buffer_len(&command) == 0)
542 /* Do not allocate a tty if stdin is not a tty. */
543 if (!isatty(fileno(stdin)) && !force_tty_flag) {
545 log("Pseudo-terminal will not be allocated because stdin is not a terminal.\n");
550 pw = getpwuid(original_real_uid);
552 log("You don't exist, go away!\n");
555 /* Take a copy of the returned structure. */
556 memset(&pwcopy, 0, sizeof(pwcopy));
557 pwcopy.pw_name = xstrdup(pw->pw_name);
558 pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
559 pwcopy.pw_uid = pw->pw_uid;
560 pwcopy.pw_gid = pw->pw_gid;
561 #ifdef HAVE_PW_CLASS_IN_PASSWD
562 pwcopy.pw_class = xstrdup(pw->pw_class);
564 pwcopy.pw_dir = xstrdup(pw->pw_dir);
565 pwcopy.pw_shell = xstrdup(pw->pw_shell);
568 /* Initialize "log" output. Since we are the client all output
569 actually goes to the terminal. */
570 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
572 /* Read per-user configuration file. */
573 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
574 read_config_file(buf, host, &options);
576 /* Read systemwide configuration file. */
577 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
579 /* Fill configuration defaults. */
580 fill_default_options(&options);
583 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
585 if (options.user == NULL)
586 options.user = xstrdup(pw->pw_name);
588 if (options.hostname != NULL)
589 host = options.hostname;
591 /* Disable rhosts authentication if not running as root. */
593 /* Ignore uid if running under Windows */
594 if (!options.use_privileged_port) {
596 if (original_effective_uid != 0 || !options.use_privileged_port) {
598 debug("Rhosts Authentication disabled, "
599 "originating port will not be trusted.");
600 options.rhosts_authentication = 0;
603 * If using rsh has been selected, exec it now (without trying
604 * anything else). Note that we must release privileges first.
606 if (options.use_rsh) {
608 * Restore our superuser privileges. This must be done
609 * before permanently setting the uid.
613 /* Switch to the original uid permanently. */
614 permanently_set_uid(original_real_uid);
617 rsh_connect(host, options.user, &command);
618 fatal("rsh_connect returned");
620 /* Restore our superuser privileges. */
623 /* Open a connection to the remote host. */
625 ok = ssh_connect(host, &hostaddr, options.port,
626 options.connection_attempts,
627 original_effective_uid != 0 || !options.use_privileged_port,
629 options.proxy_command);
632 * If we successfully made the connection, load the host private key
633 * in case we will need it later for combined rsa-rhosts
634 * authentication. This must be done before releasing extra
635 * privileges, because the file is only readable by root.
637 if (ok && (options.protocol & SSH_PROTO_1)) {
639 host_private_key = RSA_new();
641 k.rsa = host_private_key;
642 if (load_private_key(_PATH_HOST_KEY_FILE, "", &k, NULL))
643 host_private_key_loaded = 1;
646 * Get rid of any extra privileges that we may have. We will no
647 * longer need them. Also, extra privileges could make it very hard
648 * to read identity files and other non-world-readable files from the
649 * user's home directory if it happens to be on a NFS volume where
650 * root is mapped to nobody.
654 * Note that some legacy systems need to postpone the following call
655 * to permanently_set_uid() until the private hostkey is destroyed
656 * with RSA_free(). Otherwise the calling user could ptrace() the
657 * process, read the private hostkey and impersonate the host.
658 * OpenBSD does not allow ptracing of setuid processes.
660 permanently_set_uid(original_real_uid);
663 * Now that we are back to our own permissions, create ~/.ssh
664 * directory if it doesn\'t already exist.
666 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR);
667 if (stat(buf, &st) < 0)
668 if (mkdir(buf, 0700) < 0)
669 error("Could not create directory '%.200s'.", buf);
671 /* Check if the connection failed, and try "rsh" if appropriate. */
673 if (options.port != 0)
674 log("Secure connection to %.100s on port %hu refused%.100s.",
676 options.fallback_to_rsh ? "; reverting to insecure method" : "");
678 log("Secure connection to %.100s refused%.100s.", host,
679 options.fallback_to_rsh ? "; reverting to insecure method" : "");
681 if (options.fallback_to_rsh) {
682 rsh_connect(host, options.user, &command);
683 fatal("rsh_connect returned");
687 /* Expand ~ in options.identity_files, known host file names. */
689 for (i = 0; i < options.num_identity_files; i++) {
690 options.identity_files[i] =
691 tilde_expand_filename(options.identity_files[i], original_real_uid);
692 options.identity_files_type[i] = guess_identity_file_type(options.identity_files[i]);
693 debug("identity file %s type %d", options.identity_files[i],
694 options.identity_files_type[i]);
696 options.system_hostfile =
697 tilde_expand_filename(options.system_hostfile, original_real_uid);
698 options.user_hostfile =
699 tilde_expand_filename(options.user_hostfile, original_real_uid);
700 options.system_hostfile2 =
701 tilde_expand_filename(options.system_hostfile2, original_real_uid);
702 options.user_hostfile2 =
703 tilde_expand_filename(options.user_hostfile2, original_real_uid);
705 /* Log into the remote system. This never returns if the login fails. */
706 ssh_login(host_private_key_loaded, host_private_key,
707 host, (struct sockaddr *)&hostaddr, original_real_uid);
709 /* We no longer need the host private key. Clear it now. */
710 if (host_private_key_loaded)
711 RSA_free(host_private_key); /* Destroys contents safely */
713 exit_status = compat20 ? ssh_session2() : ssh_session();
719 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
725 if (options.xauth_location) {
726 /* Try to get Xauthority information for the display. */
727 snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL,
728 options.xauth_location, getenv("DISPLAY"));
729 f = popen(line, "r");
730 if (f && fgets(line, sizeof(line), f) &&
731 sscanf(line, "%*s %s %s", proto, data) == 2)
737 * If we didn't get authentication data, just make up some
738 * data. The forwarding code will check the validity of the
739 * response anyway, and substitute this data. The X11
740 * server, however, will ignore this fake data and use
741 * whatever authentication mechanisms it was using otherwise
742 * for the local connection.
747 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
748 for (i = 0; i < 16; i++) {
751 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
758 ssh_init_forwarding(void)
763 /* Initiate local TCP/IP port forwardings. */
764 for (i = 0; i < options.num_local_forwards; i++) {
765 debug("Connections to local port %d forwarded to remote address %.200s:%d",
766 options.local_forwards[i].port,
767 options.local_forwards[i].host,
768 options.local_forwards[i].host_port);
769 success += channel_request_local_forwarding(
770 options.local_forwards[i].port,
771 options.local_forwards[i].host,
772 options.local_forwards[i].host_port,
773 options.gateway_ports);
775 if (i > 0 && success == 0)
776 error("Could not request local forwarding.");
778 /* Initiate remote TCP/IP port forwardings. */
779 for (i = 0; i < options.num_remote_forwards; i++) {
780 debug("Connections to remote port %d forwarded to local address %.200s:%d",
781 options.remote_forwards[i].port,
782 options.remote_forwards[i].host,
783 options.remote_forwards[i].host_port);
784 channel_request_remote_forwarding(
785 options.remote_forwards[i].port,
786 options.remote_forwards[i].host,
787 options.remote_forwards[i].host_port);
792 check_agent_present(void)
794 if (options.forward_agent) {
795 /* Clear agent forwarding if we don\'t have an agent. */
796 int authfd = ssh_get_authentication_socket();
798 options.forward_agent = 0;
800 ssh_close_authentication_socket(authfd);
814 /* Enable compression if requested. */
815 if (options.compression) {
816 debug("Requesting compression at level %d.", options.compression_level);
818 if (options.compression_level < 1 || options.compression_level > 9)
819 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
821 /* Send the request. */
822 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
823 packet_put_int(options.compression_level);
826 type = packet_read(&plen);
827 if (type == SSH_SMSG_SUCCESS)
828 packet_start_compression(options.compression_level);
829 else if (type == SSH_SMSG_FAILURE)
830 log("Warning: Remote host refused compression.");
832 packet_disconnect("Protocol error waiting for compression response.");
834 /* Allocate a pseudo tty if appropriate. */
836 debug("Requesting pty.");
838 /* Start the packet. */
839 packet_start(SSH_CMSG_REQUEST_PTY);
841 /* Store TERM in the packet. There is no limit on the
842 length of the string. */
846 packet_put_string(cp, strlen(cp));
848 /* Store window size in the packet. */
849 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
850 memset(&ws, 0, sizeof(ws));
851 packet_put_int(ws.ws_row);
852 packet_put_int(ws.ws_col);
853 packet_put_int(ws.ws_xpixel);
854 packet_put_int(ws.ws_ypixel);
856 /* Store tty modes in the packet. */
857 tty_make_modes(fileno(stdin));
859 /* Send the packet, and wait for it to leave. */
863 /* Read response from the server. */
864 type = packet_read(&plen);
865 if (type == SSH_SMSG_SUCCESS) {
868 } else if (type == SSH_SMSG_FAILURE)
869 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
871 packet_disconnect("Protocol error waiting for pty request response.");
873 /* Request X11 forwarding if enabled and DISPLAY is set. */
874 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
875 char proto[512], data[512];
876 /* Get reasonable local authentication information. */
877 x11_get_proto(proto, sizeof proto, data, sizeof data);
878 /* Request forwarding with authentication spoofing. */
879 debug("Requesting X11 forwarding with authentication spoofing.");
880 x11_request_forwarding_with_spoofing(0, proto, data);
882 /* Read response from the server. */
883 type = packet_read(&plen);
884 if (type == SSH_SMSG_SUCCESS) {
886 } else if (type == SSH_SMSG_FAILURE) {
887 log("Warning: Remote host denied X11 forwarding.");
889 packet_disconnect("Protocol error waiting for X11 forwarding");
892 /* Tell the packet module whether this is an interactive session. */
893 packet_set_interactive(interactive);
895 /* Request authentication agent forwarding if appropriate. */
896 check_agent_present();
898 if (options.forward_agent) {
899 debug("Requesting authentication agent forwarding.");
900 auth_request_forwarding();
902 /* Read response from the server. */
903 type = packet_read(&plen);
904 packet_integrity_check(plen, 0, type);
905 if (type != SSH_SMSG_SUCCESS)
906 log("Warning: Remote host denied authentication agent forwarding.");
909 /* Initiate port forwardings. */
910 ssh_init_forwarding();
912 /* If requested, let ssh continue in the background. */
913 if (fork_after_authentication_flag)
914 if (daemon(1, 1) < 0)
915 fatal("daemon() failed: %.200s", strerror(errno));
918 * If a command was specified on the command line, execute the
919 * command now. Otherwise request the server to start a shell.
921 if (buffer_len(&command) > 0) {
922 int len = buffer_len(&command);
925 debug("Sending command: %.*s", len, buffer_ptr(&command));
926 packet_start(SSH_CMSG_EXEC_CMD);
927 packet_put_string(buffer_ptr(&command), buffer_len(&command));
931 debug("Requesting shell.");
932 packet_start(SSH_CMSG_EXEC_SHELL);
937 /* Enter the interactive session. */
938 return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0);
942 client_subsystem_reply(int type, int plen, void *ctxt)
946 id = packet_get_int();
947 len = buffer_len(&command);
950 if (type == SSH2_MSG_CHANNEL_FAILURE)
951 fatal("Request for subsystem '%.*s' failed on channel %d",
952 len, buffer_ptr(&command), id);
956 ssh_session2_callback(int id, void *arg)
961 debug("client_init id %d arg %ld", id, (long)arg);
972 /* Store window size in the packet. */
973 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
974 memset(&ws, 0, sizeof(ws));
976 channel_request_start(id, "pty-req", 0);
977 packet_put_cstring(cp);
978 packet_put_int(ws.ws_col);
979 packet_put_int(ws.ws_row);
980 packet_put_int(ws.ws_xpixel);
981 packet_put_int(ws.ws_ypixel);
982 packet_put_cstring(""); /* XXX: encode terminal modes */
985 /* XXX wait for reply */
987 if (options.forward_x11 &&
988 getenv("DISPLAY") != NULL) {
989 char proto[512], data[512];
990 /* Get reasonable local authentication information. */
991 x11_get_proto(proto, sizeof proto, data, sizeof data);
992 /* Request forwarding with authentication spoofing. */
993 debug("Requesting X11 forwarding with authentication spoofing.");
994 x11_request_forwarding_with_spoofing(id, proto, data);
996 /* XXX wait for reply */
999 check_agent_present();
1000 if (options.forward_agent) {
1001 debug("Requesting authentication agent forwarding.");
1002 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1006 len = buffer_len(&command);
1010 if (subsystem_flag) {
1011 debug("Sending subsystem: %.*s", len, buffer_ptr(&command));
1012 channel_request_start(id, "subsystem", /*want reply*/ 1);
1013 /* register callback for reply */
1014 /* XXX we asume that client_loop has already been called */
1015 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
1016 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
1018 debug("Sending command: %.*s", len, buffer_ptr(&command));
1019 channel_request_start(id, "exec", 0);
1021 packet_put_string(buffer_ptr(&command), len);
1024 channel_request(id, "shell", 0);
1026 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
1029 /* register different callback, etc. XXX */
1030 packet_set_interactive(interactive);
1036 int window, packetmax, id;
1039 if (stdin_null_flag) {
1040 in = open(_PATH_DEVNULL, O_RDONLY);
1042 in = dup(STDIN_FILENO);
1044 out = dup(STDOUT_FILENO);
1045 err = dup(STDERR_FILENO);
1047 if (in < 0 || out < 0 || err < 0)
1048 fatal("dup() in/out/err failed");
1050 /* enable nonblocking unless tty */
1058 /* XXX should be pre-session */
1059 ssh_init_forwarding();
1061 /* If requested, let ssh continue in the background. */
1062 if (fork_after_authentication_flag)
1063 if (daemon(1, 1) < 0)
1064 fatal("daemon() failed: %.200s", strerror(errno));
1066 window = CHAN_SES_WINDOW_DEFAULT;
1067 packetmax = CHAN_SES_PACKET_DEFAULT;
1073 "session", SSH_CHANNEL_OPENING, in, out, err,
1074 window, packetmax, CHAN_EXTENDED_WRITE,
1075 xstrdup("client-session"), /*nonblock*/0);
1078 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1079 ssh_session2_callback, (void *)0);
1081 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);
1085 guess_identity_file_type(const char *filename)
1089 int type = KEY_RSA1; /* default */
1091 if (stat(filename, &st) < 0) {
1092 /* ignore this key */
1095 public = key_new(type);
1096 if (!load_public_key(filename, public, NULL)) {
1097 /* ok, so we will assume this is 'some' key */