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 1.106 2001/04/05 21:05:24 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, " -C Enable compression.\n");
182 fprintf(stderr, " -N Do not execute a shell or command.\n");
183 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
184 fprintf(stderr, " -1 Force protocol version 1.\n");
185 fprintf(stderr, " -2 Force protocol version 2.\n");
186 fprintf(stderr, " -4 Use IPv4 only.\n");
187 fprintf(stderr, " -6 Use IPv6 only.\n");
188 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
189 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
194 * Connects to the given host using rsh (or prints an error message and exits
195 * if rsh is not available). This function never returns.
198 rsh_connect(char *host, char *user, Buffer * command)
203 log("Using rsh. WARNING: Connection will not be encrypted.");
204 /* Build argument list for rsh. */
206 args[i++] = _PATH_RSH;
207 /* host may have to come after user on some systems */
213 if (buffer_len(command) > 0) {
214 buffer_append(command, "\0", 1);
215 args[i++] = buffer_ptr(command);
219 for (i = 0; args[i]; i++) {
221 fprintf(stderr, " ");
222 fprintf(stderr, "%s", args[i]);
224 fprintf(stderr, "\n");
226 execv(_PATH_RSH, args);
231 int ssh_session(void);
232 int ssh_session2(void);
233 void load_public_identity_files(void);
236 * Main program for the ssh client.
239 main(int ac, char **av)
241 int i, opt, optind, exit_status, ok;
242 u_short fwd_port, fwd_host_port;
243 char *optarg, *cp, buf[256];
247 uid_t original_effective_uid;
249 __progname = get_progname(av[0]);
253 * Save the original real uid. It will be needed later (uid-swapping
254 * may clobber the real uid).
256 original_real_uid = getuid();
257 original_effective_uid = geteuid();
259 #ifdef HAVE_SETRLIMIT
260 /* If we are installed setuid root be careful to not drop core. */
261 if (original_real_uid != original_effective_uid) {
263 rlim.rlim_cur = rlim.rlim_max = 0;
264 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
265 fatal("setrlimit failed: %.100s", strerror(errno));
269 * Use uid-swapping to give up root privileges for the duration of
270 * option processing. We will re-instantiate the rights when we are
271 * ready to create the privileged port, and will permanently drop
272 * them when the port has been created (actually, when the connection
273 * has been made, as we may need to create the port several times).
275 temporarily_use_uid(original_real_uid);
278 * Set our umask to something reasonable, as some files are created
279 * with the default umask. This will make them world-readable but
280 * writable only by the owner, which is ok for all files for which we
281 * don't set the modes explicitly.
285 /* Initialize option structure to indicate that no values have been set. */
286 initialize_options(&options);
288 /* Parse command-line arguments. */
291 for (optind = 1; optind < ac; optind++) {
292 if (av[optind][0] != '-') {
295 if ((cp = strchr(av[optind], '@'))) {
298 options.user = av[optind];
308 if (strchr("eilcmpLRo", opt)) { /* options with arguments */
309 optarg = av[optind] + 2;
310 if (strcmp(optarg, "") == 0) {
311 if (optind >= ac - 1)
313 optarg = av[++optind];
322 options.protocol = SSH_PROTO_1;
325 options.protocol = SSH_PROTO_2;
337 fork_after_authentication_flag = 1;
341 options.forward_x11 = 0;
344 options.forward_x11 = 1;
347 options.gateway_ports = 1;
350 options.use_privileged_port = 0;
353 options.forward_agent = 0;
356 options.forward_agent = 1;
360 options.kerberos_tgt_passing = 0;
361 options.afs_token_passing = 0;
365 if (stat(optarg, &st) < 0) {
366 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
370 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
371 fatal("Too many identity files specified (max %d)",
372 SSH_MAX_IDENTITY_FILES);
373 options.identity_files[options.num_identity_files++] = xstrdup(optarg);
381 if (0 == debug_flag) {
383 options.log_level = SYSLOG_LEVEL_DEBUG1;
384 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
388 fatal("Too high debugging level.");
393 "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n",
395 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
396 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2,
402 options.log_level = SYSLOG_LEVEL_QUIET;
405 if (optarg[0] == '^' && optarg[2] == 0 &&
406 (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128)
407 options.escape_char = (u_char) optarg[1] & 31;
408 else if (strlen(optarg) == 1)
409 options.escape_char = (u_char) optarg[0];
410 else if (strcmp(optarg, "none") == 0)
411 options.escape_char = -2;
413 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
418 if (ciphers_valid(optarg)) {
420 options.ciphers = xstrdup(optarg);
421 options.cipher = SSH_CIPHER_ILLEGAL;
424 options.cipher = cipher_number(optarg);
425 if (options.cipher == -1) {
426 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
429 if (options.cipher == SSH_CIPHER_3DES) {
430 options.ciphers = "3des-cbc";
431 } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
432 options.ciphers = "blowfish-cbc";
434 options.ciphers = (char *)-1;
439 if (mac_valid(optarg))
440 options.macs = xstrdup(optarg);
442 fprintf(stderr, "Unknown mac type '%s'\n", optarg);
447 options.port = atoi(optarg);
450 options.user = optarg;
453 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
454 &fwd_host_port) != 3 &&
455 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
456 &fwd_host_port) != 3) {
457 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
461 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
464 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
465 &fwd_host_port) != 3 &&
466 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
467 &fwd_host_port) != 3) {
468 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
472 add_local_forward(&options, fwd_port, buf, fwd_host_port);
475 options.compression = 1;
486 if (process_config_line(&options, host ? host : "", optarg,
487 "command-line", 0, &dummy) != 0)
498 /* Check that we got a host name. */
502 SSLeay_add_all_algorithms();
503 ERR_load_crypto_strings();
505 /* Initialize the command to execute on remote host. */
506 buffer_init(&command);
509 * Save the command to execute on the remote host in a buffer. There
510 * is no limit on the length of the command, except by the maximum
511 * packet size. Also sets the tty flag if there is no command.
514 /* No command specified - execute shell on a tty. */
516 if (subsystem_flag) {
517 fprintf(stderr, "You must specify a subsystem to invoke.");
521 /* A command has been specified. Store it into the
523 for (i = optind; i < ac; i++) {
525 buffer_append(&command, " ", 1);
526 buffer_append(&command, av[i], strlen(av[i]));
530 /* Cannot fork to background if no command. */
531 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
532 fatal("Cannot fork into background without a command to execute.");
534 /* Allocate a tty by default if no command specified. */
535 if (buffer_len(&command) == 0)
541 /* Do not allocate a tty if stdin is not a tty. */
542 if (!isatty(fileno(stdin)) && !force_tty_flag) {
544 log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
549 pw = getpwuid(original_real_uid);
551 log("You don't exist, go away!");
554 /* Take a copy of the returned structure. */
558 * Initialize "log" output. Since we are the client all output
559 * actually goes to stderr.
561 log_init(av[0], SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_USER, 1);
563 /* Read per-user configuration file. */
564 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
565 read_config_file(buf, host, &options);
567 /* Read systemwide configuration file. */
568 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
570 /* Fill configuration defaults. */
571 fill_default_options(&options);
574 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
578 if (options.user == NULL)
579 options.user = xstrdup(pw->pw_name);
581 if (options.hostname != NULL)
582 host = options.hostname;
584 /* Disable rhosts authentication if not running as root. */
586 /* Ignore uid if running under Windows */
587 if (!options.use_privileged_port) {
589 if (original_effective_uid != 0 || !options.use_privileged_port) {
591 debug("Rhosts Authentication disabled, "
592 "originating port will not be trusted.");
593 options.rhosts_authentication = 0;
596 * If using rsh has been selected, exec it now (without trying
597 * anything else). Note that we must release privileges first.
599 if (options.use_rsh) {
601 * Restore our superuser privileges. This must be done
602 * before permanently setting the uid.
606 /* Switch to the original uid permanently. */
607 permanently_set_uid(original_real_uid);
610 rsh_connect(host, options.user, &command);
611 fatal("rsh_connect returned");
613 /* Restore our superuser privileges. */
616 /* Open a connection to the remote host. */
618 ok = ssh_connect(host, &hostaddr, options.port,
619 options.connection_attempts,
620 original_effective_uid != 0 || !options.use_privileged_port,
622 options.proxy_command);
625 * If we successfully made the connection, load the host private key
626 * in case we will need it later for combined rsa-rhosts
627 * authentication. This must be done before releasing extra
628 * privileges, because the file is only readable by root.
630 if (ok && (options.protocol & SSH_PROTO_1)) {
631 host_private_key = key_load_private_type(KEY_RSA1,
632 _PATH_HOST_KEY_FILE, "", NULL);
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 /* load options.identity_files */
677 load_public_identity_files();
679 /* Expand ~ in known host file names. */
681 options.system_hostfile =
682 tilde_expand_filename(options.system_hostfile, original_real_uid);
683 options.user_hostfile =
684 tilde_expand_filename(options.user_hostfile, original_real_uid);
685 options.system_hostfile2 =
686 tilde_expand_filename(options.system_hostfile2, original_real_uid);
687 options.user_hostfile2 =
688 tilde_expand_filename(options.user_hostfile2, original_real_uid);
690 /* Log into the remote system. This never returns if the login fails. */
691 ssh_login(host_private_key, host, (struct sockaddr *)&hostaddr,
694 /* We no longer need the host private key. Clear it now. */
695 if (host_private_key != NULL)
696 key_free(host_private_key); /* Destroys contents safely */
698 exit_status = compat20 ? ssh_session2() : ssh_session();
704 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
710 if (options.xauth_location) {
711 /* Try to get Xauthority information for the display. */
712 snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL,
713 options.xauth_location, getenv("DISPLAY"));
714 f = popen(line, "r");
715 if (f && fgets(line, sizeof(line), f) &&
716 sscanf(line, "%*s %s %s", proto, data) == 2)
722 * If we didn't get authentication data, just make up some
723 * data. The forwarding code will check the validity of the
724 * response anyway, and substitute this data. The X11
725 * server, however, will ignore this fake data and use
726 * whatever authentication mechanisms it was using otherwise
727 * for the local connection.
732 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
733 for (i = 0; i < 16; i++) {
736 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
743 ssh_init_forwarding(void)
748 /* Initiate local TCP/IP port forwardings. */
749 for (i = 0; i < options.num_local_forwards; i++) {
750 debug("Connections to local port %d forwarded to remote address %.200s:%d",
751 options.local_forwards[i].port,
752 options.local_forwards[i].host,
753 options.local_forwards[i].host_port);
754 success += channel_request_local_forwarding(
755 options.local_forwards[i].port,
756 options.local_forwards[i].host,
757 options.local_forwards[i].host_port,
758 options.gateway_ports);
760 if (i > 0 && success == 0)
761 error("Could not request local forwarding.");
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 client_subsystem_reply(int type, int plen, void *ctxt)
931 id = packet_get_int();
932 len = buffer_len(&command);
936 if (type == SSH2_MSG_CHANNEL_FAILURE)
937 fatal("Request for subsystem '%.*s' failed on channel %d",
938 len, buffer_ptr(&command), id);
942 ssh_session2_callback(int id, void *arg)
947 debug("client_init id %d arg %ld", id, (long)arg);
955 /* Store window size in the packet. */
956 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
957 memset(&ws, 0, sizeof(ws));
959 channel_request_start(id, "pty-req", 0);
960 packet_put_cstring(cp);
961 packet_put_int(ws.ws_col);
962 packet_put_int(ws.ws_row);
963 packet_put_int(ws.ws_xpixel);
964 packet_put_int(ws.ws_ypixel);
965 packet_put_cstring(""); /* XXX: encode terminal modes */
968 /* XXX wait for reply */
970 if (options.forward_x11 &&
971 getenv("DISPLAY") != NULL) {
972 char proto[512], data[512];
973 /* Get reasonable local authentication information. */
974 x11_get_proto(proto, sizeof proto, data, sizeof data);
975 /* Request forwarding with authentication spoofing. */
976 debug("Requesting X11 forwarding with authentication spoofing.");
977 x11_request_forwarding_with_spoofing(id, proto, data);
979 /* XXX wait for reply */
982 check_agent_present();
983 if (options.forward_agent) {
984 debug("Requesting authentication agent forwarding.");
985 channel_request_start(id, "auth-agent-req@openssh.com", 0);
989 len = buffer_len(&command);
993 if (subsystem_flag) {
994 debug("Sending subsystem: %.*s", len, buffer_ptr(&command));
995 channel_request_start(id, "subsystem", /*want reply*/ 1);
996 /* register callback for reply */
997 /* XXX we asume that client_loop has already been called */
998 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
999 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
1001 debug("Sending command: %.*s", len, buffer_ptr(&command));
1002 channel_request_start(id, "exec", 0);
1004 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1007 channel_request(id, "shell", 0);
1009 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
1011 /* register different callback, etc. XXX */
1012 packet_set_interactive(interactive);
1016 ssh_session2_command(void)
1018 int id, window, packetmax;
1021 if (stdin_null_flag) {
1022 in = open(_PATH_DEVNULL, O_RDONLY);
1024 in = dup(STDIN_FILENO);
1026 out = dup(STDOUT_FILENO);
1027 err = dup(STDERR_FILENO);
1029 if (in < 0 || out < 0 || err < 0)
1030 fatal("dup() in/out/err failed");
1032 /* enable nonblocking unless tty */
1040 window = CHAN_SES_WINDOW_DEFAULT;
1041 packetmax = CHAN_SES_PACKET_DEFAULT;
1047 "session", SSH_CHANNEL_OPENING, in, out, err,
1048 window, packetmax, CHAN_EXTENDED_WRITE,
1049 xstrdup("client-session"), /*nonblock*/0);
1051 debug("channel_new: %d", id);
1054 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1055 ssh_session2_callback, (void *)0);
1065 /* XXX should be pre-session */
1066 ssh_init_forwarding();
1068 id = no_shell_flag ? -1 : ssh_session2_command();
1070 /* If requested, let ssh continue in the background. */
1071 if (fork_after_authentication_flag)
1072 if (daemon(1, 1) < 0)
1073 fatal("daemon() failed: %.200s", strerror(errno));
1075 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);
1079 load_public_identity_files(void)
1085 for (i = 0; i < options.num_identity_files; i++) {
1086 filename = tilde_expand_filename(options.identity_files[i],
1088 public = key_load_public(filename, NULL);
1089 debug("identity file %s type %d", filename,
1090 public ? public->type : -1);
1091 xfree(options.identity_files[i]);
1092 options.identity_files[i] = filename;
1093 options.identity_keys[i] = public;