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 1.129 2001/07/11 16:29:59 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"
73 #include <openssl/engine.h>
77 #ifdef HAVE___PROGNAME
78 extern char *__progname;
83 /* Flag indicating whether IPv4 or IPv6. This can be set on the command line.
84 Default value is AF_UNSPEC means both IPv4 and IPv6. */
86 int IPv4or6 = AF_INET;
88 int IPv4or6 = AF_UNSPEC;
91 /* Flag indicating whether debug mode is on. This can be set on the command line. */
94 /* Flag indicating whether a tty should be allocated */
97 int force_tty_flag = 0;
99 /* don't exec a shell */
100 int no_shell_flag = 0;
103 * Flag indicating that nothing should be read from stdin. This can be set
104 * on the command line.
106 int stdin_null_flag = 0;
109 * Flag indicating that ssh should fork after authentication. This is useful
110 * so that the pasphrase can be entered manually, and then ssh goes to the
113 int fork_after_authentication_flag = 0;
116 * General data structure for command line options and options configurable
117 * in configuration files. See readconf.h.
122 * Name of the host we are connecting to. This is the name given on the
123 * command line, or the HostName specified for the user-supplied name in a
124 * configuration file.
128 /* socket address the host resolves to */
129 struct sockaddr_storage hostaddr;
132 * Flag to indicate that we have received a window change signal which has
133 * not yet been processed. This will cause a message indicating the new
134 * window size to be sent to the server a little later. This is volatile
135 * because this is updated in a signal handler.
137 volatile int received_window_change_signal = 0;
139 /* Private host keys. */
145 /* Original real UID. */
146 uid_t original_real_uid;
148 /* command to be executed */
151 /* Should we execute a command or invoke a subsystem? */
152 int subsystem_flag = 0;
155 /* Smartcard reader id */
156 int sc_reader_num = -1;
159 /* Prints a help message to the user. This function never returns. */
164 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
165 fprintf(stderr, "Options:\n");
166 fprintf(stderr, " -l user Log in using this user name.\n");
167 fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n");
168 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
169 fprintf(stderr, " -a Disable authentication agent forwarding (default).\n");
171 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
173 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
174 fprintf(stderr, " -x Disable X11 connection forwarding (default).\n");
175 fprintf(stderr, " -i file Identity for public key authentication "
176 "(default: ~/.ssh/identity)\n");
177 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
178 fprintf(stderr, " -T Do not allocate a tty.\n");
179 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
180 fprintf(stderr, " Multiple -v increases verbosity.\n");
181 fprintf(stderr, " -V Display version number only.\n");
182 fprintf(stderr, " -P Don't allocate a privileged port.\n");
183 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
184 fprintf(stderr, " -f Fork into background after authentication.\n");
185 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
187 fprintf(stderr, " -c cipher Select encryption algorithm\n");
188 fprintf(stderr, " -m macs Specify MAC algorithms for protocol version 2.\n");
189 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
190 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
191 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
192 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
193 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
194 fprintf(stderr, " -C Enable compression.\n");
195 fprintf(stderr, " -N Do not execute a shell or command.\n");
196 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
197 fprintf(stderr, " -1 Force protocol version 1.\n");
198 fprintf(stderr, " -2 Force protocol version 2.\n");
199 fprintf(stderr, " -4 Use IPv4 only.\n");
200 fprintf(stderr, " -6 Use IPv6 only.\n");
201 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
202 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
203 fprintf(stderr, " -b addr Local IP address.\n");
208 * Connects to the given host using rsh (or prints an error message and exits
209 * if rsh is not available). This function never returns.
212 rsh_connect(char *host, char *user, Buffer * command)
217 log("Using rsh. WARNING: Connection will not be encrypted.");
218 /* Build argument list for rsh. */
220 args[i++] = _PATH_RSH;
221 /* host may have to come after user on some systems */
227 if (buffer_len(command) > 0) {
228 buffer_append(command, "\0", 1);
229 args[i++] = buffer_ptr(command);
233 for (i = 0; args[i]; i++) {
235 fprintf(stderr, " ");
236 fprintf(stderr, "%s", args[i]);
238 fprintf(stderr, "\n");
240 execv(_PATH_RSH, args);
245 static int ssh_session(void);
246 static int ssh_session2(void);
247 static void load_public_identity_files(void);
250 * Main program for the ssh client.
253 main(int ac, char **av)
255 int i, opt, exit_status, ok;
256 u_short fwd_port, fwd_host_port;
257 char *p, *cp, buf[256];
261 uid_t original_effective_uid;
263 __progname = get_progname(av[0]);
267 * Save the original real uid. It will be needed later (uid-swapping
268 * may clobber the real uid).
270 original_real_uid = getuid();
271 original_effective_uid = geteuid();
273 #ifdef HAVE_SETRLIMIT
274 /* If we are installed setuid root be careful to not drop core. */
275 if (original_real_uid != original_effective_uid) {
277 rlim.rlim_cur = rlim.rlim_max = 0;
278 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
279 fatal("setrlimit failed: %.100s", strerror(errno));
283 pw = getpwuid(original_real_uid);
285 log("You don't exist, go away!");
288 /* Take a copy of the returned structure. */
292 * Use uid-swapping to give up root privileges for the duration of
293 * option processing. We will re-instantiate the rights when we are
294 * ready to create the privileged port, and will permanently drop
295 * them when the port has been created (actually, when the connection
296 * has been made, as we may need to create the port several times).
298 temporarily_use_uid(pw);
301 * Set our umask to something reasonable, as some files are created
302 * with the default umask. This will make them world-readable but
303 * writable only by the owner, which is ok for all files for which we
304 * don't set the modes explicitly.
308 /* Initialize option structure to indicate that no values have been set. */
309 initialize_options(&options);
311 /* Parse command-line arguments. */
315 while ((opt = getopt(ac, av,
316 "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:I:L:NPR:TVX")) != -1) {
319 options.protocol = SSH_PROTO_1;
322 options.protocol = SSH_PROTO_2;
334 fork_after_authentication_flag = 1;
338 options.forward_x11 = 0;
341 options.forward_x11 = 1;
344 options.gateway_ports = 1;
347 options.use_privileged_port = 0;
350 options.forward_agent = 0;
353 options.forward_agent = 1;
357 options.kerberos_tgt_passing = 0;
358 options.afs_token_passing = 0;
362 if (stat(optarg, &st) < 0) {
363 fprintf(stderr, "Warning: Identity file %s "
364 "does not exist.\n", optarg);
367 if (options.num_identity_files >=
368 SSH_MAX_IDENTITY_FILES)
369 fatal("Too many identity files specified "
370 "(max %d)", SSH_MAX_IDENTITY_FILES);
371 options.identity_files[options.num_identity_files++] =
376 sc_reader_num = atoi(optarg);
378 fprintf(stderr, "no support for smartcards.\n");
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.");
398 "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n",
400 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
401 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2,
407 options.log_level = SYSLOG_LEVEL_QUIET;
410 if (optarg[0] == '^' && optarg[2] == 0 &&
411 (u_char) optarg[1] >= 64 &&
412 (u_char) optarg[1] < 128)
413 options.escape_char = (u_char) optarg[1] & 31;
414 else if (strlen(optarg) == 1)
415 options.escape_char = (u_char) optarg[0];
416 else if (strcmp(optarg, "none") == 0)
417 options.escape_char = SSH_ESCAPECHAR_NONE;
419 fprintf(stderr, "Bad escape character '%s'.\n",
425 if (ciphers_valid(optarg)) {
427 options.ciphers = xstrdup(optarg);
428 options.cipher = SSH_CIPHER_ILLEGAL;
431 options.cipher = cipher_number(optarg);
432 if (options.cipher == -1) {
434 "Unknown cipher type '%s'\n",
438 if (options.cipher == SSH_CIPHER_3DES)
439 options.ciphers = "3des-cbc";
440 else if (options.cipher == SSH_CIPHER_BLOWFISH)
441 options.ciphers = "blowfish-cbc";
443 options.ciphers = (char *)-1;
447 if (mac_valid(optarg))
448 options.macs = xstrdup(optarg);
450 fprintf(stderr, "Unknown mac type '%s'\n",
456 options.port = a2port(optarg);
457 if (options.port == 0) {
458 fprintf(stderr, "Bad port '%s'\n", optarg);
463 options.user = optarg;
466 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
467 &fwd_host_port) != 3 &&
468 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
469 &fwd_host_port) != 3) {
471 "Bad forwarding specification '%s'.\n",
476 add_remote_forward(&options, fwd_port, buf,
480 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
481 &fwd_host_port) != 3 &&
482 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
483 &fwd_host_port) != 3) {
485 "Bad forwarding specification '%s'.\n",
490 add_local_forward(&options, fwd_port, buf,
495 fwd_port = a2port(optarg);
497 fprintf(stderr, "Bad dynamic port '%s'\n",
501 add_local_forward(&options, fwd_port, "socks4", 0);
505 options.compression = 1;
516 if (process_config_line(&options, host ? host : "",
517 optarg, "command-line", 0, &dummy) != 0)
524 options.bind_address = optarg;
534 if (ac > 0 && !host && **av != '-') {
535 if (strchr(*av, '@')) {
538 if (cp == NULL || cp == p)
553 /* Check that we got a host name. */
557 SSLeay_add_all_algorithms();
558 ERR_load_crypto_strings();
560 /* Initialize the command to execute on remote host. */
561 buffer_init(&command);
564 * Save the command to execute on the remote host in a buffer. There
565 * is no limit on the length of the command, except by the maximum
566 * packet size. Also sets the tty flag if there is no command.
569 /* No command specified - execute shell on a tty. */
571 if (subsystem_flag) {
573 "You must specify a subsystem to invoke.\n");
577 /* A command has been specified. Store it into the buffer. */
578 for (i = 0; i < ac; i++) {
580 buffer_append(&command, " ", 1);
581 buffer_append(&command, av[i], strlen(av[i]));
585 /* Cannot fork to background if no command. */
586 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
587 fatal("Cannot fork into background without a command to execute.");
589 /* Allocate a tty by default if no command specified. */
590 if (buffer_len(&command) == 0)
596 /* Do not allocate a tty if stdin is not a tty. */
597 if (!isatty(fileno(stdin)) && !force_tty_flag) {
599 log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
604 * Initialize "log" output. Since we are the client all output
605 * actually goes to stderr.
607 log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
608 SYSLOG_FACILITY_USER, 1);
610 /* Read per-user configuration file. */
611 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
612 read_config_file(buf, host, &options);
614 /* Read systemwide configuration file. */
615 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
617 /* Fill configuration defaults. */
618 fill_default_options(&options);
621 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
625 if (options.user == NULL)
626 options.user = xstrdup(pw->pw_name);
628 if (options.hostname != NULL)
629 host = options.hostname;
631 /* Disable rhosts authentication if not running as root. */
633 /* Ignore uid if running under Windows */
634 if (!options.use_privileged_port) {
636 if (original_effective_uid != 0 || !options.use_privileged_port) {
638 debug("Rhosts Authentication disabled, "
639 "originating port will not be trusted.");
640 options.rhosts_authentication = 0;
643 * If using rsh has been selected, exec it now (without trying
644 * anything else). Note that we must release privileges first.
646 if (options.use_rsh) {
648 * Restore our superuser privileges. This must be done
649 * before permanently setting the uid.
653 /* Switch to the original uid permanently. */
654 permanently_set_uid(pw);
657 rsh_connect(host, options.user, &command);
658 fatal("rsh_connect returned");
660 /* Restore our superuser privileges. */
663 /* Open a connection to the remote host. */
665 ok = ssh_connect(host, &hostaddr, options.port,
666 options.connection_attempts,
667 original_effective_uid != 0 || !options.use_privileged_port,
668 pw, options.proxy_command);
671 * If we successfully made the connection, load the host private key
672 * in case we will need it later for combined rsa-rhosts
673 * authentication. This must be done before releasing extra
674 * privileges, because the file is only readable by root.
676 sensitive_data.nkeys = 0;
677 sensitive_data.keys = NULL;
678 if (ok && (options.rhosts_rsa_authentication ||
679 options.hostbased_authentication)) {
680 sensitive_data.nkeys = 3;
681 sensitive_data.keys = xmalloc(sensitive_data.nkeys*sizeof(Key));
682 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
683 _PATH_HOST_KEY_FILE, "", NULL);
684 sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
685 _PATH_HOST_DSA_KEY_FILE, "", NULL);
686 sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
687 _PATH_HOST_RSA_KEY_FILE, "", NULL);
690 * Get rid of any extra privileges that we may have. We will no
691 * longer need them. Also, extra privileges could make it very hard
692 * to read identity files and other non-world-readable files from the
693 * user's home directory if it happens to be on a NFS volume where
694 * root is mapped to nobody.
698 * Note that some legacy systems need to postpone the following call
699 * to permanently_set_uid() until the private hostkey is destroyed
700 * with RSA_free(). Otherwise the calling user could ptrace() the
701 * process, read the private hostkey and impersonate the host.
702 * OpenBSD does not allow ptracing of setuid processes.
704 permanently_set_uid(pw);
707 * Now that we are back to our own permissions, create ~/.ssh
708 * directory if it doesn\'t already exist.
710 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR);
711 if (stat(buf, &st) < 0)
712 if (mkdir(buf, 0700) < 0)
713 error("Could not create directory '%.200s'.", buf);
715 /* Check if the connection failed, and try "rsh" if appropriate. */
717 if (options.port != 0)
718 log("Secure connection to %.100s on port %hu refused%.100s.",
720 options.fallback_to_rsh ? "; reverting to insecure method" : "");
722 log("Secure connection to %.100s refused%.100s.", host,
723 options.fallback_to_rsh ? "; reverting to insecure method" : "");
725 if (options.fallback_to_rsh) {
726 rsh_connect(host, options.user, &command);
727 fatal("rsh_connect returned");
731 /* load options.identity_files */
732 load_public_identity_files();
734 /* Expand ~ in known host file names. */
736 options.system_hostfile =
737 tilde_expand_filename(options.system_hostfile, original_real_uid);
738 options.user_hostfile =
739 tilde_expand_filename(options.user_hostfile, original_real_uid);
740 options.system_hostfile2 =
741 tilde_expand_filename(options.system_hostfile2, original_real_uid);
742 options.user_hostfile2 =
743 tilde_expand_filename(options.user_hostfile2, original_real_uid);
745 /* Log into the remote system. This never returns if the login fails. */
746 ssh_login(sensitive_data.keys, sensitive_data.nkeys,
747 host, (struct sockaddr *)&hostaddr, pw);
749 /* We no longer need the private host keys. Clear them now. */
750 if (sensitive_data.nkeys != 0) {
751 for (i = 0; i < sensitive_data.nkeys; i++) {
752 if (sensitive_data.keys[i] != NULL) {
753 /* Destroys contents safely */
754 debug3("clear hostkey %d", i);
755 key_free(sensitive_data.keys[i]);
756 sensitive_data.keys[i] = NULL;
759 xfree(sensitive_data.keys);
762 exit_status = compat20 ? ssh_session2() : ssh_session();
768 x11_get_proto(char *proto, int proto_len, char *data, int data_len)
774 if (options.xauth_location) {
775 /* Try to get Xauthority information for the display. */
776 snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL,
777 options.xauth_location, getenv("DISPLAY"));
778 f = popen(line, "r");
779 if (f && fgets(line, sizeof(line), f) &&
780 sscanf(line, "%*s %s %s", proto, data) == 2)
786 * If we didn't get authentication data, just make up some
787 * data. The forwarding code will check the validity of the
788 * response anyway, and substitute this data. The X11
789 * server, however, will ignore this fake data and use
790 * whatever authentication mechanisms it was using otherwise
791 * for the local connection.
796 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
797 for (i = 0; i < 16; i++) {
800 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
807 ssh_init_forwarding(void)
812 /* Initiate local TCP/IP port forwardings. */
813 for (i = 0; i < options.num_local_forwards; i++) {
814 debug("Connections to local port %d forwarded to remote address %.200s:%d",
815 options.local_forwards[i].port,
816 options.local_forwards[i].host,
817 options.local_forwards[i].host_port);
818 success += channel_request_local_forwarding(
819 options.local_forwards[i].port,
820 options.local_forwards[i].host,
821 options.local_forwards[i].host_port,
822 options.gateway_ports);
824 if (i > 0 && success == 0)
825 error("Could not request local forwarding.");
827 /* Initiate remote TCP/IP port forwardings. */
828 for (i = 0; i < options.num_remote_forwards; i++) {
829 debug("Connections to remote port %d forwarded to local address %.200s:%d",
830 options.remote_forwards[i].port,
831 options.remote_forwards[i].host,
832 options.remote_forwards[i].host_port);
833 channel_request_remote_forwarding(
834 options.remote_forwards[i].port,
835 options.remote_forwards[i].host,
836 options.remote_forwards[i].host_port);
841 check_agent_present(void)
843 if (options.forward_agent) {
844 /* Clear agent forwarding if we don\'t have an agent. */
845 int authfd = ssh_get_authentication_socket();
847 options.forward_agent = 0;
849 ssh_close_authentication_socket(authfd);
863 /* Enable compression if requested. */
864 if (options.compression) {
865 debug("Requesting compression at level %d.", options.compression_level);
867 if (options.compression_level < 1 || options.compression_level > 9)
868 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
870 /* Send the request. */
871 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
872 packet_put_int(options.compression_level);
875 type = packet_read(&plen);
876 if (type == SSH_SMSG_SUCCESS)
877 packet_start_compression(options.compression_level);
878 else if (type == SSH_SMSG_FAILURE)
879 log("Warning: Remote host refused compression.");
881 packet_disconnect("Protocol error waiting for compression response.");
883 /* Allocate a pseudo tty if appropriate. */
885 debug("Requesting pty.");
887 /* Start the packet. */
888 packet_start(SSH_CMSG_REQUEST_PTY);
890 /* Store TERM in the packet. There is no limit on the
891 length of the string. */
895 packet_put_cstring(cp);
897 /* Store window size in the packet. */
898 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
899 memset(&ws, 0, sizeof(ws));
900 packet_put_int(ws.ws_row);
901 packet_put_int(ws.ws_col);
902 packet_put_int(ws.ws_xpixel);
903 packet_put_int(ws.ws_ypixel);
905 /* Store tty modes in the packet. */
906 tty_make_modes(fileno(stdin), NULL);
908 /* Send the packet, and wait for it to leave. */
912 /* Read response from the server. */
913 type = packet_read(&plen);
914 if (type == SSH_SMSG_SUCCESS) {
917 } else if (type == SSH_SMSG_FAILURE)
918 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
920 packet_disconnect("Protocol error waiting for pty request response.");
922 /* Request X11 forwarding if enabled and DISPLAY is set. */
923 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
924 char proto[512], data[512];
925 /* Get reasonable local authentication information. */
926 x11_get_proto(proto, sizeof proto, data, sizeof data);
927 /* Request forwarding with authentication spoofing. */
928 debug("Requesting X11 forwarding with authentication spoofing.");
929 x11_request_forwarding_with_spoofing(0, proto, data);
931 /* Read response from the server. */
932 type = packet_read(&plen);
933 if (type == SSH_SMSG_SUCCESS) {
935 } else if (type == SSH_SMSG_FAILURE) {
936 log("Warning: Remote host denied X11 forwarding.");
938 packet_disconnect("Protocol error waiting for X11 forwarding");
941 /* Tell the packet module whether this is an interactive session. */
942 packet_set_interactive(interactive);
944 /* Request authentication agent forwarding if appropriate. */
945 check_agent_present();
947 if (options.forward_agent) {
948 debug("Requesting authentication agent forwarding.");
949 auth_request_forwarding();
951 /* Read response from the server. */
952 type = packet_read(&plen);
953 packet_integrity_check(plen, 0, type);
954 if (type != SSH_SMSG_SUCCESS)
955 log("Warning: Remote host denied authentication agent forwarding.");
958 /* Initiate port forwardings. */
959 ssh_init_forwarding();
961 /* If requested, let ssh continue in the background. */
962 if (fork_after_authentication_flag)
963 if (daemon(1, 1) < 0)
964 fatal("daemon() failed: %.200s", strerror(errno));
967 * If a command was specified on the command line, execute the
968 * command now. Otherwise request the server to start a shell.
970 if (buffer_len(&command) > 0) {
971 int len = buffer_len(&command);
974 debug("Sending command: %.*s", len, buffer_ptr(&command));
975 packet_start(SSH_CMSG_EXEC_CMD);
976 packet_put_string(buffer_ptr(&command), buffer_len(&command));
980 debug("Requesting shell.");
981 packet_start(SSH_CMSG_EXEC_SHELL);
986 /* Enter the interactive session. */
987 return client_loop(have_tty, tty_flag ?
988 options.escape_char : SSH_ESCAPECHAR_NONE, 0);
992 client_subsystem_reply(int type, int plen, void *ctxt)
996 id = packet_get_int();
997 len = buffer_len(&command);
1001 if (type == SSH2_MSG_CHANNEL_FAILURE)
1002 fatal("Request for subsystem '%.*s' failed on channel %d",
1003 len, buffer_ptr(&command), id);
1007 ssh_session2_callback(int id, void *arg)
1010 int interactive = 0;
1013 debug("client_init id %d arg %ld", id, (long)arg);
1018 cp = getenv("TERM");
1021 /* Store window size in the packet. */
1022 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1023 memset(&ws, 0, sizeof(ws));
1025 channel_request_start(id, "pty-req", 0);
1026 packet_put_cstring(cp);
1027 packet_put_int(ws.ws_col);
1028 packet_put_int(ws.ws_row);
1029 packet_put_int(ws.ws_xpixel);
1030 packet_put_int(ws.ws_ypixel);
1031 tio = get_saved_tio();
1032 tty_make_modes(/*ignored*/ 0, &tio);
1035 /* XXX wait for reply */
1037 if (options.forward_x11 &&
1038 getenv("DISPLAY") != NULL) {
1039 char proto[512], data[512];
1040 /* Get reasonable local authentication information. */
1041 x11_get_proto(proto, sizeof proto, data, sizeof data);
1042 /* Request forwarding with authentication spoofing. */
1043 debug("Requesting X11 forwarding with authentication spoofing.");
1044 x11_request_forwarding_with_spoofing(id, proto, data);
1046 /* XXX wait for reply */
1049 check_agent_present();
1050 if (options.forward_agent) {
1051 debug("Requesting authentication agent forwarding.");
1052 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1056 len = buffer_len(&command);
1060 if (subsystem_flag) {
1061 debug("Sending subsystem: %.*s", len, buffer_ptr(&command));
1062 channel_request_start(id, "subsystem", /*want reply*/ 1);
1063 /* register callback for reply */
1064 /* XXX we asume that client_loop has already been called */
1065 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
1066 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
1068 debug("Sending command: %.*s", len, buffer_ptr(&command));
1069 channel_request_start(id, "exec", 0);
1071 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1074 channel_request(id, "shell", 0);
1076 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
1078 /* register different callback, etc. XXX */
1079 packet_set_interactive(interactive);
1083 ssh_session2_command(void)
1086 int window, packetmax, in, out, err;
1088 if (stdin_null_flag) {
1089 in = open(_PATH_DEVNULL, O_RDONLY);
1091 in = dup(STDIN_FILENO);
1093 out = dup(STDOUT_FILENO);
1094 err = dup(STDERR_FILENO);
1096 if (in < 0 || out < 0 || err < 0)
1097 fatal("dup() in/out/err failed");
1099 /* enable nonblocking unless tty */
1107 window = CHAN_SES_WINDOW_DEFAULT;
1108 packetmax = CHAN_SES_PACKET_DEFAULT;
1114 "session", SSH_CHANNEL_OPENING, in, out, err,
1115 window, packetmax, CHAN_EXTENDED_WRITE,
1116 xstrdup("client-session"), /*nonblock*/0);
1118 fatal("ssh_session2_command: channel_new failed");
1120 debug3("ssh_session2_command: channel_new: %d", c->self);
1122 channel_send_open(c->self);
1123 channel_register_callback(c->self, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1124 ssh_session2_callback, (void *)0);
1134 /* XXX should be pre-session */
1135 ssh_init_forwarding();
1137 id = no_shell_flag ? -1 : ssh_session2_command();
1139 /* If requested, let ssh continue in the background. */
1140 if (fork_after_authentication_flag)
1141 if (daemon(1, 1) < 0)
1142 fatal("daemon() failed: %.200s", strerror(errno));
1144 return client_loop(tty_flag, tty_flag ?
1145 options.escape_char : SSH_ESCAPECHAR_NONE, id);
1149 load_public_identity_files(void)
1155 for (i = 0; i < options.num_identity_files; i++) {
1156 filename = tilde_expand_filename(options.identity_files[i],
1158 public = key_load_public(filename, NULL);
1159 debug("identity file %s type %d", filename,
1160 public ? public->type : -1);
1161 xfree(options.identity_files[i]);
1162 options.identity_files[i] = filename;
1163 options.identity_keys[i] = public;
1166 if (sc_reader_num != -1 &&
1167 options.num_identity_files + 1 < SSH_MAX_IDENTITY_FILES &&
1168 (public = sc_get_key(sc_reader_num)) != NULL ) {
1171 /* XXX ssh1 vs ssh2 */
1172 new = key_new(KEY_RSA);
1173 new->flags = KEY_FLAG_EXT;
1174 BN_copy(new->rsa->n, public->rsa->n);
1175 BN_copy(new->rsa->e, public->rsa->e);
1176 RSA_set_method(new->rsa, sc_get_engine());
1177 i = options.num_identity_files++;
1178 options.identity_keys[i] = new;
1179 options.identity_files[i] = xstrdup("smartcard rsa key");;
1181 new = key_new(KEY_RSA1);
1182 new->flags = KEY_FLAG_EXT;
1183 BN_copy(new->rsa->n, public->rsa->n);
1184 BN_copy(new->rsa->e, public->rsa->e);
1185 RSA_set_method(new->rsa, sc_get_engine());
1186 i = options.num_identity_files++;
1187 options.identity_keys[i] = new;
1188 options.identity_files[i] = xstrdup("smartcard rsa1 key");;