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 1.111 2001/04/12 14:29:09 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 /* Host private key. */
134 Key *host_private_key = NULL;
136 /* Original real UID. */
137 uid_t original_real_uid;
139 /* command to be executed */
142 /* Should we execute a command or invoke a subsystem? */
143 int subsystem_flag = 0;
145 /* Prints a help message to the user. This function never returns. */
150 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
151 fprintf(stderr, "Options:\n");
152 fprintf(stderr, " -l user Log in using this user name.\n");
153 fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n");
154 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
155 fprintf(stderr, " -a Disable authentication agent forwarding.\n");
157 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
159 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
160 fprintf(stderr, " -x Disable X11 connection forwarding.\n");
161 fprintf(stderr, " -i file Identity for public key authentication "
162 "(default: ~/.ssh/identity)\n");
163 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
164 fprintf(stderr, " -T Do not allocate a tty.\n");
165 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
166 fprintf(stderr, " Multiple -v increases verbosity.\n");
167 fprintf(stderr, " -V Display version number only.\n");
168 fprintf(stderr, " -P Don't allocate a privileged port.\n");
169 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
170 fprintf(stderr, " -f Fork into background after authentication.\n");
171 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
173 fprintf(stderr, " -c cipher Select encryption algorithm: "
174 "``3des'', ``blowfish''\n");
175 fprintf(stderr, " -m macs Specify MAC algorithms for protocol version 2.\n");
176 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
177 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
178 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
179 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
180 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
181 fprintf(stderr, " -D port Dynamically forward local port to multiple remote addresses.\n");
182 fprintf(stderr, " Allows %s to act as an application-layer proxy.\n",
184 fprintf(stderr, " Protocols supported: SOCKS4, SOCKS5, HTTPS\n");
185 fprintf(stderr, " -C Enable compression.\n");
186 fprintf(stderr, " -N Do not execute a shell or command.\n");
187 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
188 fprintf(stderr, " -1 Force protocol version 1.\n");
189 fprintf(stderr, " -2 Force protocol version 2.\n");
190 fprintf(stderr, " -4 Use IPv4 only.\n");
191 fprintf(stderr, " -6 Use IPv6 only.\n");
192 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
193 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
198 * Connects to the given host using rsh (or prints an error message and exits
199 * if rsh is not available). This function never returns.
202 rsh_connect(char *host, char *user, Buffer * command)
207 log("Using rsh. WARNING: Connection will not be encrypted.");
208 /* Build argument list for rsh. */
210 args[i++] = _PATH_RSH;
211 /* host may have to come after user on some systems */
217 if (buffer_len(command) > 0) {
218 buffer_append(command, "\0", 1);
219 args[i++] = buffer_ptr(command);
223 for (i = 0; args[i]; i++) {
225 fprintf(stderr, " ");
226 fprintf(stderr, "%s", args[i]);
228 fprintf(stderr, "\n");
230 execv(_PATH_RSH, args);
235 int ssh_session(void);
236 int ssh_session2(void);
237 void load_public_identity_files(void);
240 * Main program for the ssh client.
243 main(int ac, char **av)
245 int i, opt, optind, exit_status, ok;
246 u_short fwd_port, fwd_host_port;
247 char *optarg, *cp, *endofnumber, buf[256];
251 uid_t original_effective_uid;
253 __progname = get_progname(av[0]);
257 * Save the original real uid. It will be needed later (uid-swapping
258 * may clobber the real uid).
260 original_real_uid = getuid();
261 original_effective_uid = geteuid();
263 #ifdef HAVE_SETRLIMIT
264 /* If we are installed setuid root be careful to not drop core. */
265 if (original_real_uid != original_effective_uid) {
267 rlim.rlim_cur = rlim.rlim_max = 0;
268 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
269 fatal("setrlimit failed: %.100s", strerror(errno));
273 pw = getpwuid(original_real_uid);
275 log("You don't exist, go away!");
278 /* Take a copy of the returned structure. */
282 * Use uid-swapping to give up root privileges for the duration of
283 * option processing. We will re-instantiate the rights when we are
284 * ready to create the privileged port, and will permanently drop
285 * them when the port has been created (actually, when the connection
286 * has been made, as we may need to create the port several times).
288 temporarily_use_uid(pw);
291 * Set our umask to something reasonable, as some files are created
292 * with the default umask. This will make them world-readable but
293 * writable only by the owner, which is ok for all files for which we
294 * don't set the modes explicitly.
298 /* Initialize option structure to indicate that no values have been set. */
299 initialize_options(&options);
301 /* Parse command-line arguments. */
304 for (optind = 1; optind < ac; optind++) {
305 if (av[optind][0] != '-') {
308 if ((cp = strchr(av[optind], '@'))) {
311 options.user = av[optind];
321 if (strchr("eilcmpLRDo", opt)) { /* options with arguments */
322 optarg = av[optind] + 2;
323 if (strcmp(optarg, "") == 0) {
324 if (optind >= ac - 1)
326 optarg = av[++optind];
335 options.protocol = SSH_PROTO_1;
338 options.protocol = SSH_PROTO_2;
350 fork_after_authentication_flag = 1;
354 options.forward_x11 = 0;
357 options.forward_x11 = 1;
360 options.gateway_ports = 1;
363 options.use_privileged_port = 0;
366 options.forward_agent = 0;
369 options.forward_agent = 1;
373 options.kerberos_tgt_passing = 0;
374 options.afs_token_passing = 0;
378 if (stat(optarg, &st) < 0) {
379 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
383 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
384 fatal("Too many identity files specified (max %d)",
385 SSH_MAX_IDENTITY_FILES);
386 options.identity_files[options.num_identity_files++] = xstrdup(optarg);
394 if (0 == debug_flag) {
396 options.log_level = SYSLOG_LEVEL_DEBUG1;
397 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
401 fatal("Too high debugging level.");
406 "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n",
408 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
409 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2,
415 options.log_level = SYSLOG_LEVEL_QUIET;
418 if (optarg[0] == '^' && optarg[2] == 0 &&
419 (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128)
420 options.escape_char = (u_char) optarg[1] & 31;
421 else if (strlen(optarg) == 1)
422 options.escape_char = (u_char) optarg[0];
423 else if (strcmp(optarg, "none") == 0)
424 options.escape_char = -2;
426 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
431 if (ciphers_valid(optarg)) {
433 options.ciphers = xstrdup(optarg);
434 options.cipher = SSH_CIPHER_ILLEGAL;
437 options.cipher = cipher_number(optarg);
438 if (options.cipher == -1) {
439 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
442 if (options.cipher == SSH_CIPHER_3DES) {
443 options.ciphers = "3des-cbc";
444 } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
445 options.ciphers = "blowfish-cbc";
447 options.ciphers = (char *)-1;
452 if (mac_valid(optarg))
453 options.macs = xstrdup(optarg);
455 fprintf(stderr, "Unknown mac type '%s'\n", optarg);
460 options.port = strtol(optarg, &endofnumber, 0);
461 if (optarg == endofnumber) {
462 fprintf(stderr, "Bad port '%s'\n", optarg);
467 options.user = optarg;
470 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
471 &fwd_host_port) != 3 &&
472 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
473 &fwd_host_port) != 3) {
474 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
478 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
481 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
482 &fwd_host_port) != 3 &&
483 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
484 &fwd_host_port) != 3) {
485 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
489 add_local_forward(&options, fwd_port, buf, fwd_host_port);
493 fwd_port = strtol(optarg, &endofnumber, 0);
494 if (optarg == endofnumber) {
495 fprintf(stderr, "Bad port '%s'\n", optarg);
498 add_local_forward(&options, fwd_port, "socks4", 0);
502 options.compression = 1;
513 if (process_config_line(&options, host ? host : "", optarg,
514 "command-line", 0, &dummy) != 0)
525 /* Check that we got a host name. */
529 SSLeay_add_all_algorithms();
530 ERR_load_crypto_strings();
532 /* Initialize the command to execute on remote host. */
533 buffer_init(&command);
536 * Save the command to execute on the remote host in a buffer. There
537 * is no limit on the length of the command, except by the maximum
538 * packet size. Also sets the tty flag if there is no command.
541 /* No command specified - execute shell on a tty. */
543 if (subsystem_flag) {
544 fprintf(stderr, "You must specify a subsystem to invoke.");
548 /* A command has been specified. Store it into the
550 for (i = optind; i < ac; i++) {
552 buffer_append(&command, " ", 1);
553 buffer_append(&command, av[i], strlen(av[i]));
557 /* Cannot fork to background if no command. */
558 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
559 fatal("Cannot fork into background without a command to execute.");
561 /* Allocate a tty by default if no command specified. */
562 if (buffer_len(&command) == 0)
568 /* Do not allocate a tty if stdin is not a tty. */
569 if (!isatty(fileno(stdin)) && !force_tty_flag) {
571 log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
576 * Initialize "log" output. Since we are the client all output
577 * actually goes to stderr.
579 log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
580 SYSLOG_FACILITY_USER, 1);
582 /* Read per-user configuration file. */
583 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
584 read_config_file(buf, host, &options);
586 /* Read systemwide configuration file. */
587 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
589 /* Fill configuration defaults. */
590 fill_default_options(&options);
593 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
597 if (options.user == NULL)
598 options.user = xstrdup(pw->pw_name);
600 if (options.hostname != NULL)
601 host = options.hostname;
603 /* Disable rhosts authentication if not running as root. */
605 /* Ignore uid if running under Windows */
606 if (!options.use_privileged_port) {
608 if (original_effective_uid != 0 || !options.use_privileged_port) {
610 debug("Rhosts Authentication disabled, "
611 "originating port will not be trusted.");
612 options.rhosts_authentication = 0;
616 * If using rsh has been selected, exec it now (without trying
617 * anything else). Note that we must release privileges first.
619 if (options.use_rsh) {
621 * Restore our superuser privileges. This must be done
622 * before permanently setting the uid.
626 /* Switch to the original uid permanently. */
627 permanently_set_uid(pw);
630 rsh_connect(host, options.user, &command);
631 fatal("rsh_connect returned");
633 /* Restore our superuser privileges. */
636 /* Open a connection to the remote host. */
638 ok = ssh_connect(host, &hostaddr, options.port,
639 options.connection_attempts,
640 original_effective_uid != 0 || !options.use_privileged_port,
641 pw, options.proxy_command);
644 * If we successfully made the connection, load the host private key
645 * in case we will need it later for combined rsa-rhosts
646 * authentication. This must be done before releasing extra
647 * privileges, because the file is only readable by root.
649 if (ok && (options.protocol & SSH_PROTO_1)) {
650 host_private_key = key_load_private_type(KEY_RSA1,
651 _PATH_HOST_KEY_FILE, "", NULL);
654 * Get rid of any extra privileges that we may have. We will no
655 * longer need them. Also, extra privileges could make it very hard
656 * to read identity files and other non-world-readable files from the
657 * user's home directory if it happens to be on a NFS volume where
658 * root is mapped to nobody.
662 * Note that some legacy systems need to postpone the following call
663 * to permanently_set_uid() until the private hostkey is destroyed
664 * with RSA_free(). Otherwise the calling user could ptrace() the
665 * process, read the private hostkey and impersonate the host.
666 * OpenBSD does not allow ptracing of setuid processes.
668 permanently_set_uid(pw);
671 * Now that we are back to our own permissions, create ~/.ssh
672 * directory if it doesn\'t already exist.
674 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR);
675 if (stat(buf, &st) < 0)
676 if (mkdir(buf, 0700) < 0)
677 error("Could not create directory '%.200s'.", buf);
679 /* Check if the connection failed, and try "rsh" if appropriate. */
681 if (options.port != 0)
682 log("Secure connection to %.100s on port %hu refused%.100s.",
684 options.fallback_to_rsh ? "; reverting to insecure method" : "");
686 log("Secure connection to %.100s refused%.100s.", host,
687 options.fallback_to_rsh ? "; reverting to insecure method" : "");
689 if (options.fallback_to_rsh) {
690 rsh_connect(host, options.user, &command);
691 fatal("rsh_connect returned");
695 /* load options.identity_files */
696 load_public_identity_files();
698 /* Expand ~ in known host file names. */
700 options.system_hostfile =
701 tilde_expand_filename(options.system_hostfile, original_real_uid);
702 options.user_hostfile =
703 tilde_expand_filename(options.user_hostfile, original_real_uid);
704 options.system_hostfile2 =
705 tilde_expand_filename(options.system_hostfile2, original_real_uid);
706 options.user_hostfile2 =
707 tilde_expand_filename(options.user_hostfile2, original_real_uid);
709 /* Log into the remote system. This never returns if the login fails. */
710 ssh_login(host_private_key, host, (struct sockaddr *)&hostaddr, pw);
712 /* We no longer need the host private key. Clear it now. */
713 if (host_private_key != NULL)
714 key_free(host_private_key); /* Destroys contents safely */
716 exit_status = compat20 ? ssh_session2() : ssh_session();
722 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
728 if (options.xauth_location) {
729 /* Try to get Xauthority information for the display. */
730 snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL,
731 options.xauth_location, getenv("DISPLAY"));
732 f = popen(line, "r");
733 if (f && fgets(line, sizeof(line), f) &&
734 sscanf(line, "%*s %s %s", proto, data) == 2)
740 * If we didn't get authentication data, just make up some
741 * data. The forwarding code will check the validity of the
742 * response anyway, and substitute this data. The X11
743 * server, however, will ignore this fake data and use
744 * whatever authentication mechanisms it was using otherwise
745 * for the local connection.
750 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
751 for (i = 0; i < 16; i++) {
754 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
761 ssh_init_forwarding(void)
766 /* Initiate local TCP/IP port forwardings. */
767 for (i = 0; i < options.num_local_forwards; i++) {
768 debug("Connections to local port %d forwarded to remote address %.200s:%d",
769 options.local_forwards[i].port,
770 options.local_forwards[i].host,
771 options.local_forwards[i].host_port);
772 success += channel_request_local_forwarding(
773 options.local_forwards[i].port,
774 options.local_forwards[i].host,
775 options.local_forwards[i].host_port,
776 options.gateway_ports);
778 if (i > 0 && success == 0)
779 error("Could not request local forwarding.");
781 /* Initiate remote TCP/IP port forwardings. */
782 for (i = 0; i < options.num_remote_forwards; i++) {
783 debug("Connections to remote port %d forwarded to local address %.200s:%d",
784 options.remote_forwards[i].port,
785 options.remote_forwards[i].host,
786 options.remote_forwards[i].host_port);
787 channel_request_remote_forwarding(
788 options.remote_forwards[i].port,
789 options.remote_forwards[i].host,
790 options.remote_forwards[i].host_port);
795 check_agent_present(void)
797 if (options.forward_agent) {
798 /* Clear agent forwarding if we don\'t have an agent. */
799 int authfd = ssh_get_authentication_socket();
801 options.forward_agent = 0;
803 ssh_close_authentication_socket(authfd);
817 /* Enable compression if requested. */
818 if (options.compression) {
819 debug("Requesting compression at level %d.", options.compression_level);
821 if (options.compression_level < 1 || options.compression_level > 9)
822 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
824 /* Send the request. */
825 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
826 packet_put_int(options.compression_level);
829 type = packet_read(&plen);
830 if (type == SSH_SMSG_SUCCESS)
831 packet_start_compression(options.compression_level);
832 else if (type == SSH_SMSG_FAILURE)
833 log("Warning: Remote host refused compression.");
835 packet_disconnect("Protocol error waiting for compression response.");
837 /* Allocate a pseudo tty if appropriate. */
839 debug("Requesting pty.");
841 /* Start the packet. */
842 packet_start(SSH_CMSG_REQUEST_PTY);
844 /* Store TERM in the packet. There is no limit on the
845 length of the string. */
849 packet_put_string(cp, strlen(cp));
851 /* Store window size in the packet. */
852 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
853 memset(&ws, 0, sizeof(ws));
854 packet_put_int(ws.ws_row);
855 packet_put_int(ws.ws_col);
856 packet_put_int(ws.ws_xpixel);
857 packet_put_int(ws.ws_ypixel);
859 /* Store tty modes in the packet. */
860 tty_make_modes(fileno(stdin));
862 /* Send the packet, and wait for it to leave. */
866 /* Read response from the server. */
867 type = packet_read(&plen);
868 if (type == SSH_SMSG_SUCCESS) {
871 } else if (type == SSH_SMSG_FAILURE)
872 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
874 packet_disconnect("Protocol error waiting for pty request response.");
876 /* Request X11 forwarding if enabled and DISPLAY is set. */
877 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
878 char proto[512], data[512];
879 /* Get reasonable local authentication information. */
880 x11_get_proto(proto, sizeof proto, data, sizeof data);
881 /* Request forwarding with authentication spoofing. */
882 debug("Requesting X11 forwarding with authentication spoofing.");
883 x11_request_forwarding_with_spoofing(0, proto, data);
885 /* Read response from the server. */
886 type = packet_read(&plen);
887 if (type == SSH_SMSG_SUCCESS) {
889 } else if (type == SSH_SMSG_FAILURE) {
890 log("Warning: Remote host denied X11 forwarding.");
892 packet_disconnect("Protocol error waiting for X11 forwarding");
895 /* Tell the packet module whether this is an interactive session. */
896 packet_set_interactive(interactive);
898 /* Request authentication agent forwarding if appropriate. */
899 check_agent_present();
901 if (options.forward_agent) {
902 debug("Requesting authentication agent forwarding.");
903 auth_request_forwarding();
905 /* Read response from the server. */
906 type = packet_read(&plen);
907 packet_integrity_check(plen, 0, type);
908 if (type != SSH_SMSG_SUCCESS)
909 log("Warning: Remote host denied authentication agent forwarding.");
912 /* Initiate port forwardings. */
913 ssh_init_forwarding();
915 /* If requested, let ssh continue in the background. */
916 if (fork_after_authentication_flag)
917 if (daemon(1, 1) < 0)
918 fatal("daemon() failed: %.200s", strerror(errno));
921 * If a command was specified on the command line, execute the
922 * command now. Otherwise request the server to start a shell.
924 if (buffer_len(&command) > 0) {
925 int len = buffer_len(&command);
928 debug("Sending command: %.*s", len, buffer_ptr(&command));
929 packet_start(SSH_CMSG_EXEC_CMD);
930 packet_put_string(buffer_ptr(&command), buffer_len(&command));
934 debug("Requesting shell.");
935 packet_start(SSH_CMSG_EXEC_SHELL);
940 /* Enter the interactive session. */
941 return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0);
945 client_subsystem_reply(int type, int plen, void *ctxt)
949 id = packet_get_int();
950 len = buffer_len(&command);
954 if (type == SSH2_MSG_CHANNEL_FAILURE)
955 fatal("Request for subsystem '%.*s' failed on channel %d",
956 len, buffer_ptr(&command), id);
960 ssh_session2_callback(int id, void *arg)
965 debug("client_init id %d arg %ld", id, (long)arg);
973 /* Store window size in the packet. */
974 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
975 memset(&ws, 0, sizeof(ws));
977 channel_request_start(id, "pty-req", 0);
978 packet_put_cstring(cp);
979 packet_put_int(ws.ws_col);
980 packet_put_int(ws.ws_row);
981 packet_put_int(ws.ws_xpixel);
982 packet_put_int(ws.ws_ypixel);
983 packet_put_cstring(""); /* XXX: encode terminal modes */
986 /* XXX wait for reply */
988 if (options.forward_x11 &&
989 getenv("DISPLAY") != NULL) {
990 char proto[512], data[512];
991 /* Get reasonable local authentication information. */
992 x11_get_proto(proto, sizeof proto, data, sizeof data);
993 /* Request forwarding with authentication spoofing. */
994 debug("Requesting X11 forwarding with authentication spoofing.");
995 x11_request_forwarding_with_spoofing(id, proto, data);
997 /* XXX wait for reply */
1000 check_agent_present();
1001 if (options.forward_agent) {
1002 debug("Requesting authentication agent forwarding.");
1003 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1007 len = buffer_len(&command);
1011 if (subsystem_flag) {
1012 debug("Sending subsystem: %.*s", len, buffer_ptr(&command));
1013 channel_request_start(id, "subsystem", /*want reply*/ 1);
1014 /* register callback for reply */
1015 /* XXX we asume that client_loop has already been called */
1016 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
1017 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
1019 debug("Sending command: %.*s", len, buffer_ptr(&command));
1020 channel_request_start(id, "exec", 0);
1022 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1025 channel_request(id, "shell", 0);
1027 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
1029 /* register different callback, etc. XXX */
1030 packet_set_interactive(interactive);
1034 ssh_session2_command(void)
1036 int id, window, packetmax;
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 window = CHAN_SES_WINDOW_DEFAULT;
1059 packetmax = CHAN_SES_PACKET_DEFAULT;
1065 "session", SSH_CHANNEL_OPENING, in, out, err,
1066 window, packetmax, CHAN_EXTENDED_WRITE,
1067 xstrdup("client-session"), /*nonblock*/0);
1069 debug("channel_new: %d", id);
1072 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1073 ssh_session2_callback, (void *)0);
1083 /* XXX should be pre-session */
1084 ssh_init_forwarding();
1086 id = no_shell_flag ? -1 : ssh_session2_command();
1088 /* If requested, let ssh continue in the background. */
1089 if (fork_after_authentication_flag)
1090 if (daemon(1, 1) < 0)
1091 fatal("daemon() failed: %.200s", strerror(errno));
1093 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);
1097 load_public_identity_files(void)
1103 for (i = 0; i < options.num_identity_files; i++) {
1104 filename = tilde_expand_filename(options.identity_files[i],
1106 public = key_load_public(filename, NULL);
1107 debug("identity file %s type %d", filename,
1108 public ? public->type : -1);
1109 xfree(options.identity_files[i]);
1110 options.identity_files[i] = filename;
1111 options.identity_keys[i] = public;