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.
16 * Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved.
18 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
19 * in Canada (German citizen).
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
24 * 1. Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in the
28 * documentation and/or other materials provided with the distribution.
30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 RCSID("$OpenBSD: ssh.c,v 1.185 2002/09/11 18:27:26 stevesk Exp $");
45 #include <openssl/evp.h>
46 #include <openssl/err.h>
60 #include "pathnames.h"
61 #include "clientloop.h"
64 #include "sshconnect.h"
65 #include "tildexpand.h"
76 #ifdef HAVE___PROGNAME
77 extern char *__progname;
82 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
83 Default value is AF_UNSPEC means both IPv4 and IPv6. */
85 int IPv4or6 = AF_INET;
87 int IPv4or6 = AF_UNSPEC;
90 /* Flag indicating whether debug mode is on. This can be set on the command line. */
93 /* Flag indicating whether a tty should be allocated */
96 int force_tty_flag = 0;
98 /* don't exec a shell */
99 int no_shell_flag = 0;
102 * Flag indicating that nothing should be read from stdin. This can be set
103 * on the command line.
105 int stdin_null_flag = 0;
108 * Flag indicating that ssh should fork after authentication. This is useful
109 * so that the passphrase can be entered manually, and then ssh goes to the
112 int fork_after_authentication_flag = 0;
115 * General data structure for command line options and options configurable
116 * in configuration files. See readconf.h.
120 /* optional user configfile */
124 * Name of the host we are connecting to. This is the name given on the
125 * command line, or the HostName specified for the user-supplied name in a
126 * configuration file.
130 /* socket address the host resolves to */
131 struct sockaddr_storage hostaddr;
133 /* Private host keys. */
134 Sensitive sensitive_data;
136 /* Original real UID. */
137 uid_t original_real_uid;
138 uid_t original_effective_uid;
140 /* command to be executed */
143 /* Should we execute a command or invoke a subsystem? */
144 int subsystem_flag = 0;
146 /* # of replies received for global requests */
147 static int client_global_request_id = 0;
149 /* Prints a help message to the user. This function never returns. */
154 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
155 fprintf(stderr, "Options:\n");
156 fprintf(stderr, " -l user Log in using this user name.\n");
157 fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n");
158 fprintf(stderr, " -F config Config file (default: ~/%s).\n",
159 _PATH_SSH_USER_CONFFILE);
160 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
161 fprintf(stderr, " -a Disable authentication agent forwarding (default).\n");
163 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
165 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
166 fprintf(stderr, " -x Disable X11 connection forwarding (default).\n");
167 fprintf(stderr, " -i file Identity for public key authentication "
168 "(default: ~/.ssh/identity)\n");
170 fprintf(stderr, " -I reader Set smartcard reader.\n");
172 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
173 fprintf(stderr, " -T Do not allocate a tty.\n");
174 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
175 fprintf(stderr, " Multiple -v increases verbosity.\n");
176 fprintf(stderr, " -V Display version number only.\n");
177 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
178 fprintf(stderr, " -f Fork into background after authentication.\n");
179 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
181 fprintf(stderr, " -c cipher Select encryption algorithm\n");
182 fprintf(stderr, " -m macs Specify MAC algorithms for protocol version 2.\n");
183 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
184 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
185 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
186 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
187 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
188 fprintf(stderr, " -D port Enable dynamic application-level port forwarding.\n");
189 fprintf(stderr, " -C Enable compression.\n");
190 fprintf(stderr, " -N Do not execute a shell or command.\n");
191 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
192 fprintf(stderr, " -1 Force protocol version 1.\n");
193 fprintf(stderr, " -2 Force protocol version 2.\n");
194 fprintf(stderr, " -4 Use IPv4 only.\n");
195 fprintf(stderr, " -6 Use IPv6 only.\n");
196 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
197 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
198 fprintf(stderr, " -b addr Local IP address.\n");
202 static int ssh_session(void);
203 static int ssh_session2(void);
204 static void load_public_identity_files(void);
207 * Main program for the ssh client.
210 main(int ac, char **av)
212 int i, opt, exit_status;
213 u_short fwd_port, fwd_host_port;
214 char sfwd_port[6], sfwd_host_port[6];
215 char *p, *cp, buf[256];
219 extern int optind, optreset;
222 __progname = get_progname(av[0]);
226 * Save the original real uid. It will be needed later (uid-swapping
227 * may clobber the real uid).
229 original_real_uid = getuid();
230 original_effective_uid = geteuid();
233 * Use uid-swapping to give up root privileges for the duration of
234 * option processing. We will re-instantiate the rights when we are
235 * ready to create the privileged port, and will permanently drop
236 * them when the port has been created (actually, when the connection
237 * has been made, as we may need to create the port several times).
241 #ifdef HAVE_SETRLIMIT
242 /* If we are installed setuid root be careful to not drop core. */
243 if (original_real_uid != original_effective_uid) {
245 rlim.rlim_cur = rlim.rlim_max = 0;
246 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
247 fatal("setrlimit failed: %.100s", strerror(errno));
251 pw = getpwuid(original_real_uid);
253 log("You don't exist, go away!");
256 /* Take a copy of the returned structure. */
260 * Set our umask to something reasonable, as some files are created
261 * with the default umask. This will make them world-readable but
262 * writable only by the owner, which is ok for all files for which we
263 * don't set the modes explicitly.
267 /* Initialize option structure to indicate that no values have been set. */
268 initialize_options(&options);
270 /* Parse command-line arguments. */
274 while ((opt = getopt(ac, av,
275 "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:NPR:TVX")) != -1) {
278 options.protocol = SSH_PROTO_1;
281 options.protocol = SSH_PROTO_2;
293 fork_after_authentication_flag = 1;
297 options.forward_x11 = 0;
300 options.forward_x11 = 1;
303 options.gateway_ports = 1;
305 case 'P': /* deprecated */
306 options.use_privileged_port = 0;
309 options.forward_agent = 0;
312 options.forward_agent = 1;
316 options.kerberos_tgt_passing = 0;
317 options.afs_token_passing = 0;
321 if (stat(optarg, &st) < 0) {
322 fprintf(stderr, "Warning: Identity file %s "
323 "does not exist.\n", optarg);
326 if (options.num_identity_files >=
327 SSH_MAX_IDENTITY_FILES)
328 fatal("Too many identity files specified "
329 "(max %d)", SSH_MAX_IDENTITY_FILES);
330 options.identity_files[options.num_identity_files++] =
335 options.smartcard_device = xstrdup(optarg);
337 fprintf(stderr, "no support for smartcards.\n");
346 if (0 == debug_flag) {
348 options.log_level = SYSLOG_LEVEL_DEBUG1;
349 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
353 fatal("Too high debugging level.");
357 "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n",
359 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
360 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2,
366 options.log_level = SYSLOG_LEVEL_QUIET;
369 if (optarg[0] == '^' && optarg[2] == 0 &&
370 (u_char) optarg[1] >= 64 &&
371 (u_char) optarg[1] < 128)
372 options.escape_char = (u_char) optarg[1] & 31;
373 else if (strlen(optarg) == 1)
374 options.escape_char = (u_char) optarg[0];
375 else if (strcmp(optarg, "none") == 0)
376 options.escape_char = SSH_ESCAPECHAR_NONE;
378 fprintf(stderr, "Bad escape character '%s'.\n",
384 if (ciphers_valid(optarg)) {
386 options.ciphers = xstrdup(optarg);
387 options.cipher = SSH_CIPHER_ILLEGAL;
390 options.cipher = cipher_number(optarg);
391 if (options.cipher == -1) {
393 "Unknown cipher type '%s'\n",
397 if (options.cipher == SSH_CIPHER_3DES)
398 options.ciphers = "3des-cbc";
399 else if (options.cipher == SSH_CIPHER_BLOWFISH)
400 options.ciphers = "blowfish-cbc";
402 options.ciphers = (char *)-1;
406 if (mac_valid(optarg))
407 options.macs = xstrdup(optarg);
409 fprintf(stderr, "Unknown mac type '%s'\n",
415 options.port = a2port(optarg);
416 if (options.port == 0) {
417 fprintf(stderr, "Bad port '%s'\n", optarg);
422 options.user = optarg;
427 if (sscanf(optarg, "%5[0-9]:%255[^:]:%5[0-9]",
428 sfwd_port, buf, sfwd_host_port) != 3 &&
429 sscanf(optarg, "%5[0-9]/%255[^/]/%5[0-9]",
430 sfwd_port, buf, sfwd_host_port) != 3) {
432 "Bad forwarding specification '%s'\n",
437 if ((fwd_port = a2port(sfwd_port)) == 0 ||
438 (fwd_host_port = a2port(sfwd_host_port)) == 0) {
440 "Bad forwarding port(s) '%s'\n", optarg);
444 add_local_forward(&options, fwd_port, buf,
447 add_remote_forward(&options, fwd_port, buf,
452 fwd_port = a2port(optarg);
454 fprintf(stderr, "Bad dynamic port '%s'\n",
458 add_local_forward(&options, fwd_port, "socks4", 0);
462 options.compression = 1;
473 if (process_config_line(&options, host ? host : "",
474 optarg, "command-line", 0, &dummy) != 0)
481 options.bind_address = optarg;
494 if (ac > 0 && !host && **av != '-') {
495 if (strchr(*av, '@')) {
498 if (cp == NULL || cp == p)
513 /* Check that we got a host name. */
517 SSLeay_add_all_algorithms();
518 ERR_load_crypto_strings();
519 channel_set_af(IPv4or6);
521 /* Initialize the command to execute on remote host. */
522 buffer_init(&command);
525 * Save the command to execute on the remote host in a buffer. There
526 * is no limit on the length of the command, except by the maximum
527 * packet size. Also sets the tty flag if there is no command.
530 /* No command specified - execute shell on a tty. */
532 if (subsystem_flag) {
534 "You must specify a subsystem to invoke.\n");
538 /* A command has been specified. Store it into the buffer. */
539 for (i = 0; i < ac; i++) {
541 buffer_append(&command, " ", 1);
542 buffer_append(&command, av[i], strlen(av[i]));
546 /* Cannot fork to background if no command. */
547 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
548 fatal("Cannot fork into background without a command to execute.");
550 /* Allocate a tty by default if no command specified. */
551 if (buffer_len(&command) == 0)
557 /* Do not allocate a tty if stdin is not a tty. */
558 if (!isatty(fileno(stdin)) && !force_tty_flag) {
560 log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
565 * Initialize "log" output. Since we are the client all output
566 * actually goes to stderr.
568 log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
569 SYSLOG_FACILITY_USER, 1);
572 * Read per-user configuration file. Ignore the system wide config
573 * file if the user specifies a config file on the command line.
575 if (config != NULL) {
576 if (!read_config_file(config, host, &options))
577 fatal("Can't open user config file %.100s: "
578 "%.100s", config, strerror(errno));
580 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir,
581 _PATH_SSH_USER_CONFFILE);
582 (void)read_config_file(buf, host, &options);
584 /* Read systemwide configuration file after use config. */
585 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
588 /* Fill configuration defaults. */
589 fill_default_options(&options);
592 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
596 if (options.user == NULL)
597 options.user = xstrdup(pw->pw_name);
599 if (options.hostname != NULL)
600 host = options.hostname;
602 /* Disable rhosts authentication if not running as root. */
604 /* Ignore uid if running under Windows */
605 if (!options.use_privileged_port) {
607 if (original_effective_uid != 0 || !options.use_privileged_port) {
609 debug("Rhosts Authentication disabled, "
610 "originating port will not be trusted.");
611 options.rhosts_authentication = 0;
613 /* Open a connection to the remote host. */
615 if (ssh_connect(host, &hostaddr, options.port, IPv4or6,
616 options.connection_attempts,
618 options.use_privileged_port,
620 original_effective_uid == 0 && options.use_privileged_port,
622 options.proxy_command) != 0)
626 * If we successfully made the connection, load the host private key
627 * in case we will need it later for combined rsa-rhosts
628 * authentication. This must be done before releasing extra
629 * privileges, because the file is only readable by root.
630 * If we cannot access the private keys, load the public keys
631 * instead and try to execute the ssh-keysign helper instead.
633 sensitive_data.nkeys = 0;
634 sensitive_data.keys = NULL;
635 sensitive_data.external_keysign = 0;
636 if (options.rhosts_rsa_authentication ||
637 options.hostbased_authentication) {
638 sensitive_data.nkeys = 3;
639 sensitive_data.keys = xmalloc(sensitive_data.nkeys *
643 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
644 _PATH_HOST_KEY_FILE, "", NULL);
645 sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
646 _PATH_HOST_DSA_KEY_FILE, "", NULL);
647 sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
648 _PATH_HOST_RSA_KEY_FILE, "", NULL);
651 if (options.hostbased_authentication == 1 &&
652 sensitive_data.keys[0] == NULL &&
653 sensitive_data.keys[1] == NULL &&
654 sensitive_data.keys[2] == NULL) {
655 sensitive_data.keys[1] = key_load_public(
656 _PATH_HOST_DSA_KEY_FILE, NULL);
657 sensitive_data.keys[2] = key_load_public(
658 _PATH_HOST_RSA_KEY_FILE, NULL);
659 sensitive_data.external_keysign = 1;
663 * Get rid of any extra privileges that we may have. We will no
664 * longer need them. Also, extra privileges could make it very hard
665 * to read identity files and other non-world-readable files from the
666 * user's home directory if it happens to be on a NFS volume where
667 * root is mapped to nobody.
669 seteuid(original_real_uid);
670 setuid(original_real_uid);
673 * Now that we are back to our own permissions, create ~/.ssh
674 * directory if it doesn\'t already exist.
676 snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
677 if (stat(buf, &st) < 0)
678 if (mkdir(buf, 0700) < 0)
679 error("Could not create directory '%.200s'.", buf);
681 /* load options.identity_files */
682 load_public_identity_files();
684 /* Expand ~ in known host file names. */
686 options.system_hostfile =
687 tilde_expand_filename(options.system_hostfile, original_real_uid);
688 options.user_hostfile =
689 tilde_expand_filename(options.user_hostfile, original_real_uid);
690 options.system_hostfile2 =
691 tilde_expand_filename(options.system_hostfile2, original_real_uid);
692 options.user_hostfile2 =
693 tilde_expand_filename(options.user_hostfile2, original_real_uid);
695 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
697 /* Log into the remote system. This never returns if the login fails. */
698 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw);
700 /* We no longer need the private host keys. Clear them now. */
701 if (sensitive_data.nkeys != 0) {
702 for (i = 0; i < sensitive_data.nkeys; i++) {
703 if (sensitive_data.keys[i] != NULL) {
704 /* Destroys contents safely */
705 debug3("clear hostkey %d", i);
706 key_free(sensitive_data.keys[i]);
707 sensitive_data.keys[i] = NULL;
710 xfree(sensitive_data.keys);
712 for (i = 0; i < options.num_identity_files; i++) {
713 if (options.identity_files[i]) {
714 xfree(options.identity_files[i]);
715 options.identity_files[i] = NULL;
717 if (options.identity_keys[i]) {
718 key_free(options.identity_keys[i]);
719 options.identity_keys[i] = NULL;
723 exit_status = compat20 ? ssh_session2() : ssh_session();
729 x11_get_proto(char **_proto, char **_data)
732 static char proto[512], data[512];
740 proto[0] = data[0] = '\0';
741 if (!options.xauth_location ||
742 (stat(options.xauth_location, &st) == -1)) {
743 debug("No xauth program.");
745 if ((display = getenv("DISPLAY")) == NULL) {
746 debug("x11_get_proto: DISPLAY not set");
749 /* Try to get Xauthority information for the display. */
750 if (strncmp(display, "localhost:", 10) == 0)
752 * Handle FamilyLocal case where $DISPLAY does
753 * not match an authorization entry. For this we
754 * just try "xauth list unix:displaynum.screennum".
755 * XXX: "localhost" match to determine FamilyLocal
758 snprintf(line, sizeof line, "%s list unix:%s 2>"
759 _PATH_DEVNULL, options.xauth_location, display+10);
761 snprintf(line, sizeof line, "%s list %.200s 2>"
762 _PATH_DEVNULL, options.xauth_location, display);
763 debug2("x11_get_proto: %s", line);
764 f = popen(line, "r");
765 if (f && fgets(line, sizeof(line), f) &&
766 sscanf(line, "%*s %511s %511s", proto, data) == 2)
772 * If we didn't get authentication data, just make up some
773 * data. The forwarding code will check the validity of the
774 * response anyway, and substitute this data. The X11
775 * server, however, will ignore this fake data and use
776 * whatever authentication mechanisms it was using otherwise
777 * for the local connection.
782 log("Warning: No xauth data; using fake authentication data for X11 forwarding.");
783 strlcpy(proto, "MIT-MAGIC-COOKIE-1", sizeof proto);
784 for (i = 0; i < 16; i++) {
787 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x", rand & 0xff);
794 ssh_init_forwarding(void)
799 /* Initiate local TCP/IP port forwardings. */
800 for (i = 0; i < options.num_local_forwards; i++) {
801 debug("Connections to local port %d forwarded to remote address %.200s:%d",
802 options.local_forwards[i].port,
803 options.local_forwards[i].host,
804 options.local_forwards[i].host_port);
805 success += channel_setup_local_fwd_listener(
806 options.local_forwards[i].port,
807 options.local_forwards[i].host,
808 options.local_forwards[i].host_port,
809 options.gateway_ports);
811 if (i > 0 && success == 0)
812 error("Could not request local forwarding.");
814 /* Initiate remote TCP/IP port forwardings. */
815 for (i = 0; i < options.num_remote_forwards; i++) {
816 debug("Connections to remote port %d forwarded to local address %.200s:%d",
817 options.remote_forwards[i].port,
818 options.remote_forwards[i].host,
819 options.remote_forwards[i].host_port);
820 channel_request_remote_forwarding(
821 options.remote_forwards[i].port,
822 options.remote_forwards[i].host,
823 options.remote_forwards[i].host_port);
828 check_agent_present(void)
830 if (options.forward_agent) {
831 /* Clear agent forwarding if we don\'t have an agent. */
832 if (!ssh_agent_present())
833 options.forward_agent = 0;
846 /* Enable compression if requested. */
847 if (options.compression) {
848 debug("Requesting compression at level %d.", options.compression_level);
850 if (options.compression_level < 1 || options.compression_level > 9)
851 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
853 /* Send the request. */
854 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
855 packet_put_int(options.compression_level);
858 type = packet_read();
859 if (type == SSH_SMSG_SUCCESS)
860 packet_start_compression(options.compression_level);
861 else if (type == SSH_SMSG_FAILURE)
862 log("Warning: Remote host refused compression.");
864 packet_disconnect("Protocol error waiting for compression response.");
866 /* Allocate a pseudo tty if appropriate. */
868 debug("Requesting pty.");
870 /* Start the packet. */
871 packet_start(SSH_CMSG_REQUEST_PTY);
873 /* Store TERM in the packet. There is no limit on the
874 length of the string. */
878 packet_put_cstring(cp);
880 /* Store window size in the packet. */
881 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
882 memset(&ws, 0, sizeof(ws));
883 packet_put_int(ws.ws_row);
884 packet_put_int(ws.ws_col);
885 packet_put_int(ws.ws_xpixel);
886 packet_put_int(ws.ws_ypixel);
888 /* Store tty modes in the packet. */
889 tty_make_modes(fileno(stdin), NULL);
891 /* Send the packet, and wait for it to leave. */
895 /* Read response from the server. */
896 type = packet_read();
897 if (type == SSH_SMSG_SUCCESS) {
900 } else if (type == SSH_SMSG_FAILURE)
901 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
903 packet_disconnect("Protocol error waiting for pty request response.");
905 /* Request X11 forwarding if enabled and DISPLAY is set. */
906 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
908 /* Get reasonable local authentication information. */
909 x11_get_proto(&proto, &data);
910 /* Request forwarding with authentication spoofing. */
911 debug("Requesting X11 forwarding with authentication spoofing.");
912 x11_request_forwarding_with_spoofing(0, proto, data);
914 /* Read response from the server. */
915 type = packet_read();
916 if (type == SSH_SMSG_SUCCESS) {
918 } else if (type == SSH_SMSG_FAILURE) {
919 log("Warning: Remote host denied X11 forwarding.");
921 packet_disconnect("Protocol error waiting for X11 forwarding");
924 /* Tell the packet module whether this is an interactive session. */
925 packet_set_interactive(interactive);
927 /* Request authentication agent forwarding if appropriate. */
928 check_agent_present();
930 if (options.forward_agent) {
931 debug("Requesting authentication agent forwarding.");
932 auth_request_forwarding();
934 /* Read response from the server. */
935 type = packet_read();
937 if (type != SSH_SMSG_SUCCESS)
938 log("Warning: Remote host denied authentication agent forwarding.");
941 /* Initiate port forwardings. */
942 ssh_init_forwarding();
944 /* If requested, let ssh continue in the background. */
945 if (fork_after_authentication_flag)
946 if (daemon(1, 1) < 0)
947 fatal("daemon() failed: %.200s", strerror(errno));
950 * If a command was specified on the command line, execute the
951 * command now. Otherwise request the server to start a shell.
953 if (buffer_len(&command) > 0) {
954 int len = buffer_len(&command);
957 debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command));
958 packet_start(SSH_CMSG_EXEC_CMD);
959 packet_put_string(buffer_ptr(&command), buffer_len(&command));
963 debug("Requesting shell.");
964 packet_start(SSH_CMSG_EXEC_SHELL);
969 /* Enter the interactive session. */
970 return client_loop(have_tty, tty_flag ?
971 options.escape_char : SSH_ESCAPECHAR_NONE, 0);
975 client_subsystem_reply(int type, u_int32_t seq, void *ctxt)
979 id = packet_get_int();
980 len = buffer_len(&command);
984 if (type == SSH2_MSG_CHANNEL_FAILURE)
985 fatal("Request for subsystem '%.*s' failed on channel %d",
986 len, (u_char *)buffer_ptr(&command), id);
990 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
994 i = client_global_request_id++;
995 if (i >= options.num_remote_forwards) {
996 debug("client_global_request_reply: too many replies %d > %d",
997 i, options.num_remote_forwards);
1000 debug("remote forward %s for: listen %d, connect %s:%d",
1001 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1002 options.remote_forwards[i].port,
1003 options.remote_forwards[i].host,
1004 options.remote_forwards[i].host_port);
1005 if (type == SSH2_MSG_REQUEST_FAILURE)
1006 log("Warning: remote port forwarding failed for listen port %d",
1007 options.remote_forwards[i].port);
1010 /* request pty/x11/agent/tcpfwd/shell for channel */
1012 ssh_session2_setup(int id, void *arg)
1015 int interactive = 0;
1018 debug("ssh_session2_setup: id %d", id);
1023 cp = getenv("TERM");
1026 /* Store window size in the packet. */
1027 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1028 memset(&ws, 0, sizeof(ws));
1030 channel_request_start(id, "pty-req", 0);
1031 packet_put_cstring(cp);
1032 packet_put_int(ws.ws_col);
1033 packet_put_int(ws.ws_row);
1034 packet_put_int(ws.ws_xpixel);
1035 packet_put_int(ws.ws_ypixel);
1036 tio = get_saved_tio();
1037 tty_make_modes(/*ignored*/ 0, &tio);
1040 /* XXX wait for reply */
1042 if (options.forward_x11 &&
1043 getenv("DISPLAY") != NULL) {
1045 /* Get reasonable local authentication information. */
1046 x11_get_proto(&proto, &data);
1047 /* Request forwarding with authentication spoofing. */
1048 debug("Requesting X11 forwarding with authentication spoofing.");
1049 x11_request_forwarding_with_spoofing(id, proto, data);
1051 /* XXX wait for reply */
1054 check_agent_present();
1055 if (options.forward_agent) {
1056 debug("Requesting authentication agent forwarding.");
1057 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1061 len = buffer_len(&command);
1065 if (subsystem_flag) {
1066 debug("Sending subsystem: %.*s", len, (u_char *)buffer_ptr(&command));
1067 channel_request_start(id, "subsystem", /*want reply*/ 1);
1068 /* register callback for reply */
1069 /* XXX we assume that client_loop has already been called */
1070 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
1071 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
1073 debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command));
1074 channel_request_start(id, "exec", 0);
1076 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1079 channel_request_start(id, "shell", 0);
1083 packet_set_interactive(interactive);
1086 /* open new channel for a session */
1088 ssh_session2_open(void)
1091 int window, packetmax, in, out, err;
1093 if (stdin_null_flag) {
1094 in = open(_PATH_DEVNULL, O_RDONLY);
1096 in = dup(STDIN_FILENO);
1098 out = dup(STDOUT_FILENO);
1099 err = dup(STDERR_FILENO);
1101 if (in < 0 || out < 0 || err < 0)
1102 fatal("dup() in/out/err failed");
1104 /* enable nonblocking unless tty */
1112 window = CHAN_SES_WINDOW_DEFAULT;
1113 packetmax = CHAN_SES_PACKET_DEFAULT;
1119 "session", SSH_CHANNEL_OPENING, in, out, err,
1120 window, packetmax, CHAN_EXTENDED_WRITE,
1121 xstrdup("client-session"), /*nonblock*/0);
1123 debug3("ssh_session2_open: channel_new: %d", c->self);
1125 channel_send_open(c->self);
1127 channel_register_confirm(c->self, ssh_session2_setup);
1137 /* XXX should be pre-session */
1138 ssh_init_forwarding();
1140 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1141 id = ssh_session2_open();
1143 /* If requested, let ssh continue in the background. */
1144 if (fork_after_authentication_flag)
1145 if (daemon(1, 1) < 0)
1146 fatal("daemon() failed: %.200s", strerror(errno));
1148 return client_loop(tty_flag, tty_flag ?
1149 options.escape_char : SSH_ESCAPECHAR_NONE, id);
1153 load_public_identity_files(void)
1161 if (options.smartcard_device != NULL &&
1162 options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1163 (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) {
1165 for (i = 0; keys[i] != NULL; i++) {
1167 memmove(&options.identity_files[1], &options.identity_files[0],
1168 sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1));
1169 memmove(&options.identity_keys[1], &options.identity_keys[0],
1170 sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1));
1171 options.num_identity_files++;
1172 options.identity_keys[0] = keys[i];
1173 options.identity_files[0] = xstrdup("smartcard key");;
1175 if (options.num_identity_files > SSH_MAX_IDENTITY_FILES)
1176 options.num_identity_files = SSH_MAX_IDENTITY_FILES;
1180 #endif /* SMARTCARD */
1181 for (; i < options.num_identity_files; i++) {
1182 filename = tilde_expand_filename(options.identity_files[i],
1184 public = key_load_public(filename, NULL);
1185 debug("identity file %s type %d", filename,
1186 public ? public->type : -1);
1187 xfree(options.identity_files[i]);
1188 options.identity_files[i] = filename;
1189 options.identity_keys[i] = public;