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 1.84 2001/01/21 19:05:58 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"
68 #ifdef HAVE___PROGNAME
69 extern char *__progname;
74 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
75 Default value is AF_UNSPEC means both IPv4 and IPv6. */
77 int IPv4or6 = AF_INET;
79 int IPv4or6 = AF_UNSPEC;
82 /* Flag indicating whether debug mode is on. This can be set on the command line. */
85 /* Flag indicating whether a tty should be allocated */
88 int force_tty_flag = 0;
90 /* don't exec a shell */
91 int no_shell_flag = 0;
94 * Flag indicating that nothing should be read from stdin. This can be set
95 * on the command line.
97 int stdin_null_flag = 0;
100 * Flag indicating that ssh should fork after authentication. This is useful
101 * so that the pasphrase can be entered manually, and then ssh goes to the
104 int fork_after_authentication_flag = 0;
107 * General data structure for command line options and options configurable
108 * in configuration files. See readconf.h.
113 * Name of the host we are connecting to. This is the name given on the
114 * command line, or the HostName specified for the user-supplied name in a
115 * configuration file.
119 /* socket address the host resolves to */
120 struct sockaddr_storage hostaddr;
123 * Flag to indicate that we have received a window change signal which has
124 * not yet been processed. This will cause a message indicating the new
125 * window size to be sent to the server a little later. This is volatile
126 * because this is updated in a signal handler.
128 volatile int received_window_change_signal = 0;
130 /* Flag indicating whether we have a valid host private key loaded. */
131 int host_private_key_loaded = 0;
133 /* Host private key. */
134 RSA *host_private_key = NULL;
136 /* Original real UID. */
137 uid_t original_real_uid;
139 /* command to be executed */
142 /* Prints a help message to the user. This function never returns. */
147 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
148 fprintf(stderr, "Options:\n");
149 fprintf(stderr, " -l user Log in using this user name.\n");
150 fprintf(stderr, " -n Redirect input from /dev/null.\n");
151 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
152 fprintf(stderr, " -a Disable authentication agent forwarding.\n");
154 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
156 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
157 fprintf(stderr, " -x Disable X11 connection forwarding.\n");
158 fprintf(stderr, " -i file Identity for RSA authentication (default: ~/.ssh/identity).\n");
159 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
160 fprintf(stderr, " -T Do not allocate a tty.\n");
161 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
162 fprintf(stderr, " Multiple -v increases verbosity.\n");
163 fprintf(stderr, " -V Display version number only.\n");
164 fprintf(stderr, " -P Don't allocate a privileged port.\n");
165 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
166 fprintf(stderr, " -f Fork into background after authentication.\n");
167 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
169 fprintf(stderr, " -c cipher Select encryption algorithm: "
172 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
173 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
174 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
175 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
176 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
177 fprintf(stderr, " -C Enable compression.\n");
178 fprintf(stderr, " -N Do not execute a shell or command.\n");
179 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
180 fprintf(stderr, " -4 Use IPv4 only.\n");
181 fprintf(stderr, " -6 Use IPv6 only.\n");
182 fprintf(stderr, " -2 Force protocol version 2.\n");
183 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
188 * Connects to the given host using rsh (or prints an error message and exits
189 * if rsh is not available). This function never returns.
192 rsh_connect(char *host, char *user, Buffer * command)
197 log("Using rsh. WARNING: Connection will not be encrypted.");
198 /* Build argument list for rsh. */
200 args[i++] = _PATH_RSH;
201 /* host may have to come after user on some systems */
207 if (buffer_len(command) > 0) {
208 buffer_append(command, "\0", 1);
209 args[i++] = buffer_ptr(command);
213 for (i = 0; args[i]; i++) {
215 fprintf(stderr, " ");
216 fprintf(stderr, "%s", args[i]);
218 fprintf(stderr, "\n");
220 execv(_PATH_RSH, args);
225 int ssh_session(void);
226 int ssh_session2(void);
227 int guess_identity_file_type(const char *filename);
230 * Main program for the ssh client.
233 main(int ac, char **av)
235 int i, opt, optind, exit_status, ok;
236 u_short fwd_port, fwd_host_port;
237 char *optarg, *cp, buf[256];
239 struct passwd *pw, pwcopy;
241 uid_t original_effective_uid;
243 __progname = get_progname(av[0]);
247 * Save the original real uid. It will be needed later (uid-swapping
248 * may clobber the real uid).
250 original_real_uid = getuid();
251 original_effective_uid = geteuid();
253 #ifdef HAVE_SETRLIMIT
254 /* If we are installed setuid root be careful to not drop core. */
255 if (original_real_uid != original_effective_uid) {
257 rlim.rlim_cur = rlim.rlim_max = 0;
258 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
259 fatal("setrlimit failed: %.100s", strerror(errno));
263 * Use uid-swapping to give up root privileges for the duration of
264 * option processing. We will re-instantiate the rights when we are
265 * ready to create the privileged port, and will permanently drop
266 * them when the port has been created (actually, when the connection
267 * has been made, as we may need to create the port several times).
269 temporarily_use_uid(original_real_uid);
272 * Set our umask to something reasonable, as some files are created
273 * with the default umask. This will make them world-readable but
274 * writable only by the owner, which is ok for all files for which we
275 * don't set the modes explicitly.
279 /* Initialize option structure to indicate that no values have been set. */
280 initialize_options(&options);
282 /* Parse command-line arguments. */
285 /* If program name is not one of the standard names, use it as host name. */
288 if (strcasecmp(cp, "rsh") && strcasecmp(cp, "ssh") &&
289 strcasecmp(cp, "rlogin") && strcasecmp(cp, "slogin") &&
290 strcasecmp(cp, "remsh") &&
291 strcasecmp(cp, "rsh.exe") && strcasecmp(cp, "ssh.exe") &&
292 strcasecmp(cp, "rlogin.exe") && strcasecmp(cp, "slogin.exe") &&
293 strcasecmp(cp, "remsh.exe"))
295 if (strcmp(cp, "rsh") && strcmp(cp, "ssh") && strcmp(cp, "rlogin") &&
296 strcmp(cp, "slogin") && strcmp(cp, "remsh"))
300 for (optind = 1; optind < ac; optind++) {
301 if (av[optind][0] != '-') {
304 if ((cp = strchr(av[optind], '@'))) {
307 options.user = av[optind];
317 if (strchr("eilcpLRo", opt)) { /* options with arguments */
318 optarg = av[optind] + 2;
319 if (strcmp(optarg, "") == 0) {
320 if (optind >= ac - 1)
322 optarg = av[++optind];
331 options.protocol = SSH_PROTO_2;
343 fork_after_authentication_flag = 1;
347 options.forward_x11 = 0;
350 options.forward_x11 = 1;
353 options.gateway_ports = 1;
356 options.use_privileged_port = 0;
359 options.forward_agent = 0;
362 options.forward_agent = 1;
366 options.kerberos_tgt_passing = 0;
367 options.afs_token_passing = 0;
371 if (stat(optarg, &st) < 0) {
372 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
376 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
377 fatal("Too many identity files specified (max %d)",
378 SSH_MAX_IDENTITY_FILES);
379 options.identity_files[options.num_identity_files++] = xstrdup(optarg);
387 if (0 == debug_flag) {
389 options.log_level = SYSLOG_LEVEL_DEBUG1;
390 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
394 fatal("Too high debugging level.\n");
398 fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n",
400 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
401 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2);
402 fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay());
407 options.log_level = SYSLOG_LEVEL_QUIET;
410 if (optarg[0] == '^' && optarg[2] == 0 &&
411 (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128)
412 options.escape_char = (u_char) optarg[1] & 31;
413 else if (strlen(optarg) == 1)
414 options.escape_char = (u_char) optarg[0];
415 else if (strcmp(optarg, "none") == 0)
416 options.escape_char = -2;
418 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
423 if (ciphers_valid(optarg)) {
425 options.ciphers = xstrdup(optarg);
426 options.cipher = SSH_CIPHER_ILLEGAL;
429 options.cipher = cipher_number(optarg);
430 if (options.cipher == -1) {
431 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
434 if (options.cipher == SSH_CIPHER_3DES) {
435 options.ciphers = "3des-cbc";
436 } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
437 options.ciphers = "blowfish-cbc";
439 options.ciphers = (char *)-1;
444 options.port = atoi(optarg);
447 options.user = optarg;
450 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
451 &fwd_host_port) != 3 &&
452 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
453 &fwd_host_port) != 3) {
454 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
458 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
461 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
462 &fwd_host_port) != 3 &&
463 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
464 &fwd_host_port) != 3) {
465 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
469 add_local_forward(&options, fwd_port, buf, fwd_host_port);
472 options.compression = 1;
483 if (process_config_line(&options, host ? host : "", optarg,
484 "command-line", 0, &dummy) != 0)
492 /* Check that we got a host name. */
496 SSLeay_add_all_algorithms();
497 ERR_load_crypto_strings();
499 /* Initialize the command to execute on remote host. */
500 buffer_init(&command);
503 * Save the command to execute on the remote host in a buffer. There
504 * is no limit on the length of the command, except by the maximum
505 * packet size. Also sets the tty flag if there is no command.
508 /* No command specified - execute shell on a tty. */
511 /* A command has been specified. Store it into the
513 for (i = optind; i < ac; i++) {
515 buffer_append(&command, " ", 1);
516 buffer_append(&command, av[i], strlen(av[i]));
520 /* Cannot fork to background if no command. */
521 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
522 fatal("Cannot fork into background without a command to execute.");
524 /* Allocate a tty by default if no command specified. */
525 if (buffer_len(&command) == 0)
531 /* Do not allocate a tty if stdin is not a tty. */
532 if (!isatty(fileno(stdin)) && !force_tty_flag) {
534 log("Pseudo-terminal will not be allocated because stdin is not a terminal.\n");
539 pw = getpwuid(original_real_uid);
541 log("You don't exist, go away!\n");
544 /* Take a copy of the returned structure. */
545 memset(&pwcopy, 0, sizeof(pwcopy));
546 pwcopy.pw_name = xstrdup(pw->pw_name);
547 pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
548 pwcopy.pw_uid = pw->pw_uid;
549 pwcopy.pw_gid = pw->pw_gid;
550 #ifdef HAVE_PW_CLASS_IN_PASSWD
551 pwcopy.pw_class = xstrdup(pw->pw_class);
553 pwcopy.pw_dir = xstrdup(pw->pw_dir);
554 pwcopy.pw_shell = xstrdup(pw->pw_shell);
557 /* Initialize "log" output. Since we are the client all output
558 actually goes to the terminal. */
559 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
561 /* Read per-user configuration file. */
562 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
563 read_config_file(buf, host, &options);
565 /* Read systemwide configuration file. */
566 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
568 /* Fill configuration defaults. */
569 fill_default_options(&options);
572 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 0);
574 if (options.user == NULL)
575 options.user = xstrdup(pw->pw_name);
577 if (options.hostname != NULL)
578 host = options.hostname;
580 /* Disable rhosts authentication if not running as root. */
582 /* Ignore uid if running under Windows */
583 if (!options.use_privileged_port) {
585 if (original_effective_uid != 0 || !options.use_privileged_port) {
587 debug("Rhosts Authentication disabled, "
588 "originating port will not be trusted.");
589 options.rhosts_authentication = 0;
592 * If using rsh has been selected, exec it now (without trying
593 * anything else). Note that we must release privileges first.
595 if (options.use_rsh) {
597 * Restore our superuser privileges. This must be done
598 * before permanently setting the uid.
602 /* Switch to the original uid permanently. */
603 permanently_set_uid(original_real_uid);
606 rsh_connect(host, options.user, &command);
607 fatal("rsh_connect returned");
609 /* Restore our superuser privileges. */
612 /* Open a connection to the remote host. */
614 ok = ssh_connect(host, &hostaddr, options.port,
615 options.connection_attempts,
616 original_effective_uid != 0 || !options.use_privileged_port,
618 options.proxy_command);
621 * If we successfully made the connection, load the host private key
622 * in case we will need it later for combined rsa-rhosts
623 * authentication. This must be done before releasing extra
624 * privileges, because the file is only readable by root.
626 if (ok && (options.protocol & SSH_PROTO_1)) {
628 host_private_key = RSA_new();
630 k.rsa = host_private_key;
631 if (load_private_key(_PATH_HOST_KEY_FILE, "", &k, NULL))
632 host_private_key_loaded = 1;
635 * Get rid of any extra privileges that we may have. We will no
636 * longer need them. Also, extra privileges could make it very hard
637 * to read identity files and other non-world-readable files from the
638 * user's home directory if it happens to be on a NFS volume where
639 * root is mapped to nobody.
643 * Note that some legacy systems need to postpone the following call
644 * to permanently_set_uid() until the private hostkey is destroyed
645 * with RSA_free(). Otherwise the calling user could ptrace() the
646 * process, read the private hostkey and impersonate the host.
647 * OpenBSD does not allow ptracing of setuid processes.
649 permanently_set_uid(original_real_uid);
652 * Now that we are back to our own permissions, create ~/.ssh
653 * directory if it doesn\'t already exist.
655 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR);
656 if (stat(buf, &st) < 0)
657 if (mkdir(buf, 0700) < 0)
658 error("Could not create directory '%.200s'.", buf);
660 /* Check if the connection failed, and try "rsh" if appropriate. */
662 if (options.port != 0)
663 log("Secure connection to %.100s on port %hu refused%.100s.",
665 options.fallback_to_rsh ? "; reverting to insecure method" : "");
667 log("Secure connection to %.100s refused%.100s.", host,
668 options.fallback_to_rsh ? "; reverting to insecure method" : "");
670 if (options.fallback_to_rsh) {
671 rsh_connect(host, options.user, &command);
672 fatal("rsh_connect returned");
676 /* Expand ~ in options.identity_files, known host file names. */
678 for (i = 0; i < options.num_identity_files; i++) {
679 options.identity_files[i] =
680 tilde_expand_filename(options.identity_files[i], original_real_uid);
681 options.identity_files_type[i] = guess_identity_file_type(options.identity_files[i]);
682 debug("identity file %s type %d", options.identity_files[i],
683 options.identity_files_type[i]);
685 options.system_hostfile =
686 tilde_expand_filename(options.system_hostfile, original_real_uid);
687 options.user_hostfile =
688 tilde_expand_filename(options.user_hostfile, original_real_uid);
689 options.system_hostfile2 =
690 tilde_expand_filename(options.system_hostfile2, original_real_uid);
691 options.user_hostfile2 =
692 tilde_expand_filename(options.user_hostfile2, original_real_uid);
694 /* Log into the remote system. This never returns if the login fails. */
695 ssh_login(host_private_key_loaded, host_private_key,
696 host, (struct sockaddr *)&hostaddr, original_real_uid);
698 /* We no longer need the host private key. Clear it now. */
699 if (host_private_key_loaded)
700 RSA_free(host_private_key); /* Destroys contents safely */
702 exit_status = compat20 ? ssh_session2() : ssh_session();
708 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
714 if (options.xauth_location) {
715 /* Try to get Xauthority information for the display. */
716 snprintf(line, sizeof line, "%.100s list %.200s 2>/dev/null",
717 options.xauth_location, getenv("DISPLAY"));
718 f = popen(line, "r");
719 if (f && fgets(line, sizeof(line), f) &&
720 sscanf(line, "%*s %s %s", proto, data) == 2)
726 * If we didn't get authentication data, just make up some
727 * data. The forwarding code will check the validity of the
728 * response anyway, and substitute this data. The X11
729 * server, however, will ignore this fake data and use
730 * whatever authentication mechanisms it was using otherwise
731 * for the local connection.
736 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
737 for (i = 0; i < 16; i++) {
740 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
747 ssh_init_forwarding(void)
750 /* Initiate local TCP/IP port forwardings. */
751 for (i = 0; i < options.num_local_forwards; i++) {
752 debug("Connections to local port %d forwarded to remote address %.200s:%d",
753 options.local_forwards[i].port,
754 options.local_forwards[i].host,
755 options.local_forwards[i].host_port);
756 channel_request_local_forwarding(
757 options.local_forwards[i].port,
758 options.local_forwards[i].host,
759 options.local_forwards[i].host_port,
760 options.gateway_ports);
763 /* Initiate remote TCP/IP port forwardings. */
764 for (i = 0; i < options.num_remote_forwards; i++) {
765 debug("Connections to remote port %d forwarded to local address %.200s:%d",
766 options.remote_forwards[i].port,
767 options.remote_forwards[i].host,
768 options.remote_forwards[i].host_port);
769 channel_request_remote_forwarding(
770 options.remote_forwards[i].port,
771 options.remote_forwards[i].host,
772 options.remote_forwards[i].host_port);
777 check_agent_present(void)
779 if (options.forward_agent) {
780 /* Clear agent forwarding if we don\'t have an agent. */
781 int authfd = ssh_get_authentication_socket();
783 options.forward_agent = 0;
785 ssh_close_authentication_socket(authfd);
799 /* Enable compression if requested. */
800 if (options.compression) {
801 debug("Requesting compression at level %d.", options.compression_level);
803 if (options.compression_level < 1 || options.compression_level > 9)
804 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
806 /* Send the request. */
807 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
808 packet_put_int(options.compression_level);
811 type = packet_read(&plen);
812 if (type == SSH_SMSG_SUCCESS)
813 packet_start_compression(options.compression_level);
814 else if (type == SSH_SMSG_FAILURE)
815 log("Warning: Remote host refused compression.");
817 packet_disconnect("Protocol error waiting for compression response.");
819 /* Allocate a pseudo tty if appropriate. */
821 debug("Requesting pty.");
823 /* Start the packet. */
824 packet_start(SSH_CMSG_REQUEST_PTY);
826 /* Store TERM in the packet. There is no limit on the
827 length of the string. */
831 packet_put_string(cp, strlen(cp));
833 /* Store window size in the packet. */
834 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
835 memset(&ws, 0, sizeof(ws));
836 packet_put_int(ws.ws_row);
837 packet_put_int(ws.ws_col);
838 packet_put_int(ws.ws_xpixel);
839 packet_put_int(ws.ws_ypixel);
841 /* Store tty modes in the packet. */
842 tty_make_modes(fileno(stdin));
844 /* Send the packet, and wait for it to leave. */
848 /* Read response from the server. */
849 type = packet_read(&plen);
850 if (type == SSH_SMSG_SUCCESS) {
853 } else if (type == SSH_SMSG_FAILURE)
854 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
856 packet_disconnect("Protocol error waiting for pty request response.");
858 /* Request X11 forwarding if enabled and DISPLAY is set. */
859 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
860 char proto[512], data[512];
861 /* Get reasonable local authentication information. */
862 x11_get_proto(proto, sizeof proto, data, sizeof data);
863 /* Request forwarding with authentication spoofing. */
864 debug("Requesting X11 forwarding with authentication spoofing.");
865 x11_request_forwarding_with_spoofing(0, proto, data);
867 /* Read response from the server. */
868 type = packet_read(&plen);
869 if (type == SSH_SMSG_SUCCESS) {
871 } else if (type == SSH_SMSG_FAILURE) {
872 log("Warning: Remote host denied X11 forwarding.");
874 packet_disconnect("Protocol error waiting for X11 forwarding");
877 /* Tell the packet module whether this is an interactive session. */
878 packet_set_interactive(interactive);
880 /* Request authentication agent forwarding if appropriate. */
881 check_agent_present();
883 if (options.forward_agent) {
884 debug("Requesting authentication agent forwarding.");
885 auth_request_forwarding();
887 /* Read response from the server. */
888 type = packet_read(&plen);
889 packet_integrity_check(plen, 0, type);
890 if (type != SSH_SMSG_SUCCESS)
891 log("Warning: Remote host denied authentication agent forwarding.");
894 /* Initiate port forwardings. */
895 ssh_init_forwarding();
897 /* If requested, let ssh continue in the background. */
898 if (fork_after_authentication_flag)
899 if (daemon(1, 1) < 0)
900 fatal("daemon() failed: %.200s", strerror(errno));
903 * If a command was specified on the command line, execute the
904 * command now. Otherwise request the server to start a shell.
906 if (buffer_len(&command) > 0) {
907 int len = buffer_len(&command);
910 debug("Sending command: %.*s", len, buffer_ptr(&command));
911 packet_start(SSH_CMSG_EXEC_CMD);
912 packet_put_string(buffer_ptr(&command), buffer_len(&command));
916 debug("Requesting shell.");
917 packet_start(SSH_CMSG_EXEC_SHELL);
922 /* Enter the interactive session. */
923 return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0);
927 ssh_session2_callback(int id, void *arg)
932 debug("client_init id %d arg %d", id, (int)arg);
943 /* Store window size in the packet. */
944 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
945 memset(&ws, 0, sizeof(ws));
947 channel_request_start(id, "pty-req", 0);
948 packet_put_cstring(cp);
949 packet_put_int(ws.ws_col);
950 packet_put_int(ws.ws_row);
951 packet_put_int(ws.ws_xpixel);
952 packet_put_int(ws.ws_ypixel);
953 packet_put_cstring(""); /* XXX: encode terminal modes */
956 /* XXX wait for reply */
958 if (options.forward_x11 &&
959 getenv("DISPLAY") != NULL) {
960 char proto[512], data[512];
961 /* Get reasonable local authentication information. */
962 x11_get_proto(proto, sizeof proto, data, sizeof data);
963 /* Request forwarding with authentication spoofing. */
964 debug("Requesting X11 forwarding with authentication spoofing.");
965 x11_request_forwarding_with_spoofing(id, proto, data);
967 /* XXX wait for reply */
970 check_agent_present();
971 if (options.forward_agent) {
972 debug("Requesting authentication agent forwarding.");
973 channel_request_start(id, "auth-agent-req@openssh.com", 0);
977 len = buffer_len(&command);
981 debug("Sending command: %.*s", len, buffer_ptr(&command));
982 channel_request_start(id, "exec", 0);
983 packet_put_string(buffer_ptr(&command), len);
986 channel_request(id, "shell", 0);
988 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
990 /* register different callback, etc. XXX */
991 packet_set_interactive(interactive);
992 clientloop_set_session_ident(id);
998 int window, packetmax, id;
1001 if (stdin_null_flag) {
1002 in = open("/dev/null", O_RDONLY);
1004 in = dup(STDIN_FILENO);
1006 out = dup(STDOUT_FILENO);
1007 err = dup(STDERR_FILENO);
1009 if (in < 0 || out < 0 || err < 0)
1010 fatal("dup() in/out/err failed");
1012 /* enable nonblocking unless tty */
1020 /* XXX should be pre-session */
1021 ssh_init_forwarding();
1023 /* If requested, let ssh continue in the background. */
1024 if (fork_after_authentication_flag)
1025 if (daemon(1, 1) < 0)
1026 fatal("daemon() failed: %.200s", strerror(errno));
1028 window = CHAN_SES_WINDOW_DEFAULT;
1029 packetmax = CHAN_SES_PACKET_DEFAULT;
1035 "session", SSH_CHANNEL_OPENING, in, out, err,
1036 window, packetmax, CHAN_EXTENDED_WRITE,
1037 xstrdup("client-session"), /*nonblock*/0);
1040 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1041 ssh_session2_callback, (void *)0);
1043 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);
1047 guess_identity_file_type(const char *filename)
1051 int type = KEY_RSA1; /* default */
1053 if (stat(filename, &st) < 0) {
1054 /* ignore this key */
1057 public = key_new(type);
1058 if (!load_public_key(filename, public, NULL)) {
1059 /* ok, so we will assume this is 'some' key */