1 /* $OpenBSD: ssh.c,v 1.318 2008/07/02 13:47:39 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * Ssh client program. This program can be used to log into a remote machine.
7 * The software supports strong authentication, encryption, and forwarding
8 * of X11, TCP/IP, and authentication connections.
10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
16 * Copyright (c) 1999 Niels Provos. All rights reserved.
17 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
19 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20 * in Canada (German citizen).
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the above copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
31 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 #include <sys/types.h>
46 #ifdef HAVE_SYS_STAT_H
47 # include <sys/stat.h>
49 #include <sys/resource.h>
50 #include <sys/ioctl.h>
51 #include <sys/socket.h>
69 #include <netinet/in.h>
70 #include <arpa/inet.h>
72 #include <openssl/evp.h>
73 #include <openssl/err.h>
74 #include "openbsd-compat/openssl-compat.h"
75 #include "openbsd-compat/sys-queue.h"
89 #include "pathnames.h"
91 #include "clientloop.h"
94 #include "sshconnect.h"
108 extern char *__progname
;
110 /* Flag indicating whether debug mode is on. May be set on the command line. */
113 /* Flag indicating whether a tty should be allocated */
116 int force_tty_flag
= 0;
118 /* don't exec a shell */
119 int no_shell_flag
= 0;
122 * Flag indicating that nothing should be read from stdin. This can be set
123 * on the command line.
125 int stdin_null_flag
= 0;
128 * Flag indicating that ssh should fork after authentication. This is useful
129 * so that the passphrase can be entered manually, and then ssh goes to the
132 int fork_after_authentication_flag
= 0;
135 * General data structure for command line options and options configurable
136 * in configuration files. See readconf.h.
140 /* optional user configfile */
144 * Name of the host we are connecting to. This is the name given on the
145 * command line, or the HostName specified for the user-supplied name in a
146 * configuration file.
150 /* socket address the host resolves to */
151 struct sockaddr_storage hostaddr
;
153 /* Private host keys. */
154 Sensitive sensitive_data
;
156 /* Original real UID. */
157 uid_t original_real_uid
;
158 uid_t original_effective_uid
;
160 /* command to be executed */
163 /* Should we execute a command or invoke a subsystem? */
164 int subsystem_flag
= 0;
166 /* # of replies received for global requests */
167 static int remote_forward_confirms_received
= 0;
169 /* pid of proxycommand child process */
170 pid_t proxy_command_pid
= 0;
173 extern int muxserver_sock
;
174 extern u_int muxclient_command
;
176 /* Prints a help message to the user. This function never returns. */
182 "usage: ssh [-1246AaCfgKkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n"
183 " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
184 " [-i identity_file] [-L [bind_address:]port:host:hostport]\n"
185 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
186 " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
187 " [-w local_tun[:remote_tun]] [user@]hostname [command]\n"
192 static int ssh_session(void);
193 static int ssh_session2(void);
194 static void load_public_identity_files(void);
196 /* from muxclient.c */
197 void muxclient(const char *);
198 void muxserver_listen(void);
201 * Main program for the ssh client.
204 main(int ac
, char **av
)
206 int i
, opt
, exit_status
;
207 char *p
, *cp
, *line
, buf
[256];
210 int dummy
, timeout_ms
;
211 extern int optind
, optreset
;
216 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
219 __progname
= ssh_get_progname(av
[0]);
223 * Save the original real uid. It will be needed later (uid-swapping
224 * may clobber the real uid).
226 original_real_uid
= getuid();
227 original_effective_uid
= geteuid();
230 * Use uid-swapping to give up root privileges for the duration of
231 * option processing. We will re-instantiate the rights when we are
232 * ready to create the privileged port, and will permanently drop
233 * them when the port has been created (actually, when the connection
234 * has been made, as we may need to create the port several times).
238 #ifdef HAVE_SETRLIMIT
239 /* If we are installed setuid root be careful to not drop core. */
240 if (original_real_uid
!= original_effective_uid
) {
242 rlim
.rlim_cur
= rlim
.rlim_max
= 0;
243 if (setrlimit(RLIMIT_CORE
, &rlim
) < 0)
244 fatal("setrlimit failed: %.100s", strerror(errno
));
248 pw
= getpwuid(original_real_uid
);
250 logit("You don't exist, go away!");
253 /* Take a copy of the returned structure. */
257 * Set our umask to something reasonable, as some files are created
258 * with the default umask. This will make them world-readable but
259 * writable only by the owner, which is ok for all files for which we
260 * don't set the modes explicitly.
265 * Initialize option structure to indicate that no values have been
268 initialize_options(&options
);
270 /* Parse command-line arguments. */
274 while ((opt
= getopt(ac
, av
, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
275 "ACD:F:I:KL:MNO:PR:S:TVw:XY")) != -1) {
278 options
.protocol
= SSH_PROTO_1
;
281 options
.protocol
= SSH_PROTO_2
;
284 options
.address_family
= AF_INET
;
287 options
.address_family
= AF_INET6
;
293 fork_after_authentication_flag
= 1;
297 options
.forward_x11
= 0;
300 options
.forward_x11
= 1;
303 options
.forward_x11
= 1;
304 options
.forward_x11_trusted
= 1;
307 options
.gateway_ports
= 1;
310 if (strcmp(optarg
, "check") == 0)
311 muxclient_command
= SSHMUX_COMMAND_ALIVE_CHECK
;
312 else if (strcmp(optarg
, "exit") == 0)
313 muxclient_command
= SSHMUX_COMMAND_TERMINATE
;
315 fatal("Invalid multiplex command.");
317 case 'P': /* deprecated */
318 options
.use_privileged_port
= 0;
321 options
.forward_agent
= 0;
324 options
.forward_agent
= 1;
327 options
.gss_deleg_creds
= 0;
330 options
.gss_authentication
= 1;
331 options
.gss_deleg_creds
= 1;
334 if (stat(optarg
, &st
) < 0) {
335 fprintf(stderr
, "Warning: Identity file %s "
336 "not accessible: %s.\n", optarg
,
340 if (options
.num_identity_files
>=
341 SSH_MAX_IDENTITY_FILES
)
342 fatal("Too many identity files specified "
343 "(max %d)", SSH_MAX_IDENTITY_FILES
);
344 options
.identity_files
[options
.num_identity_files
++] =
349 options
.smartcard_device
= xstrdup(optarg
);
351 fprintf(stderr
, "no support for smartcards.\n");
360 if (debug_flag
== 0) {
362 options
.log_level
= SYSLOG_LEVEL_DEBUG1
;
364 if (options
.log_level
< SYSLOG_LEVEL_DEBUG3
)
370 fprintf(stderr
, "%s, %s\n",
371 SSH_RELEASE
, SSLeay_version(SSLEAY_VERSION
));
376 if (options
.tun_open
== -1)
377 options
.tun_open
= SSH_TUNMODE_DEFAULT
;
378 options
.tun_local
= a2tun(optarg
, &options
.tun_remote
);
379 if (options
.tun_local
== SSH_TUNID_ERR
) {
381 "Bad tun device '%s'\n", optarg
);
386 options
.log_level
= SYSLOG_LEVEL_QUIET
;
389 if (optarg
[0] == '^' && optarg
[2] == 0 &&
390 (u_char
) optarg
[1] >= 64 &&
391 (u_char
) optarg
[1] < 128)
392 options
.escape_char
= (u_char
) optarg
[1] & 31;
393 else if (strlen(optarg
) == 1)
394 options
.escape_char
= (u_char
) optarg
[0];
395 else if (strcmp(optarg
, "none") == 0)
396 options
.escape_char
= SSH_ESCAPECHAR_NONE
;
398 fprintf(stderr
, "Bad escape character '%s'.\n",
404 if (ciphers_valid(optarg
)) {
406 options
.ciphers
= xstrdup(optarg
);
407 options
.cipher
= SSH_CIPHER_INVALID
;
410 options
.cipher
= cipher_number(optarg
);
411 if (options
.cipher
== -1) {
413 "Unknown cipher type '%s'\n",
417 if (options
.cipher
== SSH_CIPHER_3DES
)
418 options
.ciphers
= "3des-cbc";
419 else if (options
.cipher
== SSH_CIPHER_BLOWFISH
)
420 options
.ciphers
= "blowfish-cbc";
422 options
.ciphers
= (char *)-1;
426 if (mac_valid(optarg
))
427 options
.macs
= xstrdup(optarg
);
429 fprintf(stderr
, "Unknown mac type '%s'\n",
435 if (options
.control_master
== SSHCTL_MASTER_YES
)
436 options
.control_master
= SSHCTL_MASTER_ASK
;
438 options
.control_master
= SSHCTL_MASTER_YES
;
441 options
.port
= a2port(optarg
);
442 if (options
.port
== 0) {
443 fprintf(stderr
, "Bad port '%s'\n", optarg
);
448 options
.user
= optarg
;
452 if (parse_forward(&fwd
, optarg
))
453 add_local_forward(&options
, &fwd
);
456 "Bad local forwarding specification '%s'\n",
463 if (parse_forward(&fwd
, optarg
)) {
464 add_remote_forward(&options
, &fwd
);
467 "Bad remote forwarding specification "
474 cp
= p
= xstrdup(optarg
);
475 memset(&fwd
, '\0', sizeof(fwd
));
476 fwd
.connect_host
= "socks";
477 if ((fwd
.listen_host
= hpdelim(&cp
)) == NULL
) {
478 fprintf(stderr
, "Bad dynamic forwarding "
479 "specification '%.100s'\n", optarg
);
483 fwd
.listen_port
= a2port(cp
);
485 cleanhostname(fwd
.listen_host
);
487 fwd
.listen_port
= a2port(fwd
.listen_host
);
488 fwd
.listen_host
= NULL
;
491 if (fwd
.listen_port
== 0) {
492 fprintf(stderr
, "Bad dynamic port '%s'\n",
496 add_local_forward(&options
, &fwd
);
501 options
.compression
= 1;
512 line
= xstrdup(optarg
);
513 if (process_config_line(&options
, host
? host
: "",
514 line
, "command-line", 0, &dummy
) != 0)
522 if (options
.control_path
!= NULL
)
523 free(options
.control_path
);
524 options
.control_path
= xstrdup(optarg
);
527 options
.bind_address
= optarg
;
540 if (ac
> 0 && !host
&& **av
!= '-') {
541 if (strrchr(*av
, '@')) {
543 cp
= strrchr(p
, '@');
544 if (cp
== NULL
|| cp
== p
)
552 optind
= optreset
= 1;
558 /* Check that we got a host name. */
562 SSLeay_add_all_algorithms();
563 ERR_load_crypto_strings();
565 /* Initialize the command to execute on remote host. */
566 buffer_init(&command
);
569 * Save the command to execute on the remote host in a buffer. There
570 * is no limit on the length of the command, except by the maximum
571 * packet size. Also sets the tty flag if there is no command.
574 /* No command specified - execute shell on a tty. */
576 if (subsystem_flag
) {
578 "You must specify a subsystem to invoke.\n");
582 /* A command has been specified. Store it into the buffer. */
583 for (i
= 0; i
< ac
; i
++) {
585 buffer_append(&command
, " ", 1);
586 buffer_append(&command
, av
[i
], strlen(av
[i
]));
590 /* Cannot fork to background if no command. */
591 if (fork_after_authentication_flag
&& buffer_len(&command
) == 0 &&
593 fatal("Cannot fork into background without a command "
596 /* Allocate a tty by default if no command specified. */
597 if (buffer_len(&command
) == 0)
603 /* Do not allocate a tty if stdin is not a tty. */
604 if ((!isatty(fileno(stdin
)) || stdin_null_flag
) && !force_tty_flag
) {
606 logit("Pseudo-terminal will not be allocated because "
607 "stdin is not a terminal.");
612 * Initialize "log" output. Since we are the client all output
613 * actually goes to stderr.
616 options
.log_level
== -1 ? SYSLOG_LEVEL_INFO
: options
.log_level
,
617 SYSLOG_FACILITY_USER
, 1);
620 * Read per-user configuration file. Ignore the system wide config
621 * file if the user specifies a config file on the command line.
623 if (config
!= NULL
) {
624 if (!read_config_file(config
, host
, &options
, 0))
625 fatal("Can't open user config file %.100s: "
626 "%.100s", config
, strerror(errno
));
628 snprintf(buf
, sizeof buf
, "%.100s/%.100s", pw
->pw_dir
,
629 _PATH_SSH_USER_CONFFILE
);
630 (void)read_config_file(buf
, host
, &options
, 1);
632 /* Read systemwide configuration file after use config. */
633 (void)read_config_file(_PATH_HOST_CONFIG_FILE
, host
,
637 /* Fill configuration defaults. */
638 fill_default_options(&options
);
640 channel_set_af(options
.address_family
);
643 log_init(av
[0], options
.log_level
, SYSLOG_FACILITY_USER
, 1);
647 if (options
.user
== NULL
)
648 options
.user
= xstrdup(pw
->pw_name
);
650 /* Get default port if port has not been set. */
651 if (options
.port
== 0) {
652 sp
= getservbyname(SSH_SERVICE_NAME
, "tcp");
653 options
.port
= sp
? ntohs(sp
->s_port
) : SSH_DEFAULT_PORT
;
656 if (options
.local_command
!= NULL
) {
657 char thishost
[NI_MAXHOST
];
659 if (gethostname(thishost
, sizeof(thishost
)) == -1)
660 fatal("gethostname: %s", strerror(errno
));
661 snprintf(buf
, sizeof(buf
), "%d", options
.port
);
662 debug3("expanding LocalCommand: %s", options
.local_command
);
663 cp
= options
.local_command
;
664 options
.local_command
= percent_expand(cp
, "d", pw
->pw_dir
,
665 "h", options
.hostname
? options
.hostname
: host
,
666 "l", thishost
, "n", host
, "r", options
.user
, "p", buf
,
667 "u", pw
->pw_name
, (char *)NULL
);
668 debug3("expanded LocalCommand: %s", options
.local_command
);
672 if (options
.hostname
!= NULL
)
673 host
= options
.hostname
;
675 /* Find canonic host name. */
676 if (strchr(host
, '.') == 0) {
677 struct addrinfo hints
;
678 struct addrinfo
*ai
= NULL
;
680 memset(&hints
, 0, sizeof(hints
));
681 hints
.ai_family
= options
.address_family
;
682 hints
.ai_flags
= AI_CANONNAME
;
683 hints
.ai_socktype
= SOCK_STREAM
;
684 errgai
= getaddrinfo(host
, NULL
, &hints
, &ai
);
686 if (ai
->ai_canonname
!= NULL
)
687 host
= xstrdup(ai
->ai_canonname
);
692 /* force lowercase for hostkey matching */
693 if (options
.host_key_alias
!= NULL
) {
694 for (p
= options
.host_key_alias
; *p
; p
++)
696 *p
= (char)tolower(*p
);
699 if (options
.proxy_command
!= NULL
&&
700 strcmp(options
.proxy_command
, "none") == 0) {
701 xfree(options
.proxy_command
);
702 options
.proxy_command
= NULL
;
704 if (options
.control_path
!= NULL
&&
705 strcmp(options
.control_path
, "none") == 0) {
706 xfree(options
.control_path
);
707 options
.control_path
= NULL
;
710 if (options
.control_path
!= NULL
) {
711 char thishost
[NI_MAXHOST
];
713 if (gethostname(thishost
, sizeof(thishost
)) == -1)
714 fatal("gethostname: %s", strerror(errno
));
715 snprintf(buf
, sizeof(buf
), "%d", options
.port
);
716 cp
= tilde_expand_filename(options
.control_path
,
718 xfree(options
.control_path
);
719 options
.control_path
= percent_expand(cp
, "p", buf
, "h", host
,
720 "r", options
.user
, "l", thishost
, (char *)NULL
);
723 if (muxclient_command
!= 0 && options
.control_path
== NULL
)
724 fatal("No ControlPath specified for \"-O\" command");
725 if (options
.control_path
!= NULL
)
726 muxclient(options
.control_path
);
728 timeout_ms
= options
.connection_timeout
* 1000;
730 /* Open a connection to the remote host. */
731 if (ssh_connect(host
, &hostaddr
, options
.port
,
732 options
.address_family
, options
.connection_attempts
, &timeout_ms
,
733 options
.tcp_keep_alive
,
735 options
.use_privileged_port
,
737 original_effective_uid
== 0 && options
.use_privileged_port
,
739 options
.proxy_command
) != 0)
743 debug3("timeout: %d ms remain after connect", timeout_ms
);
746 * If we successfully made the connection, load the host private key
747 * in case we will need it later for combined rsa-rhosts
748 * authentication. This must be done before releasing extra
749 * privileges, because the file is only readable by root.
750 * If we cannot access the private keys, load the public keys
751 * instead and try to execute the ssh-keysign helper instead.
753 sensitive_data
.nkeys
= 0;
754 sensitive_data
.keys
= NULL
;
755 sensitive_data
.external_keysign
= 0;
756 if (options
.rhosts_rsa_authentication
||
757 options
.hostbased_authentication
) {
758 sensitive_data
.nkeys
= 3;
759 sensitive_data
.keys
= xcalloc(sensitive_data
.nkeys
,
763 sensitive_data
.keys
[0] = key_load_private_type(KEY_RSA1
,
764 _PATH_HOST_KEY_FILE
, "", NULL
, NULL
);
765 sensitive_data
.keys
[1] = key_load_private_type(KEY_DSA
,
766 _PATH_HOST_DSA_KEY_FILE
, "", NULL
, NULL
);
767 sensitive_data
.keys
[2] = key_load_private_type(KEY_RSA
,
768 _PATH_HOST_RSA_KEY_FILE
, "", NULL
, NULL
);
771 if (options
.hostbased_authentication
== 1 &&
772 sensitive_data
.keys
[0] == NULL
&&
773 sensitive_data
.keys
[1] == NULL
&&
774 sensitive_data
.keys
[2] == NULL
) {
775 sensitive_data
.keys
[1] = key_load_public(
776 _PATH_HOST_DSA_KEY_FILE
, NULL
);
777 sensitive_data
.keys
[2] = key_load_public(
778 _PATH_HOST_RSA_KEY_FILE
, NULL
);
779 sensitive_data
.external_keysign
= 1;
783 * Get rid of any extra privileges that we may have. We will no
784 * longer need them. Also, extra privileges could make it very hard
785 * to read identity files and other non-world-readable files from the
786 * user's home directory if it happens to be on a NFS volume where
787 * root is mapped to nobody.
789 if (original_effective_uid
== 0) {
791 permanently_set_uid(pw
);
795 * Now that we are back to our own permissions, create ~/.ssh
796 * directory if it doesn't already exist.
798 snprintf(buf
, sizeof buf
, "%.100s%s%.100s", pw
->pw_dir
,
799 strcmp(pw
->pw_dir
, "/") ? "/" : "", _PATH_SSH_USER_DIR
);
800 if (stat(buf
, &st
) < 0)
801 if (mkdir(buf
, 0700) < 0)
802 error("Could not create directory '%.200s'.", buf
);
804 /* load options.identity_files */
805 load_public_identity_files();
807 /* Expand ~ in known host file names. */
809 options
.system_hostfile
=
810 tilde_expand_filename(options
.system_hostfile
, original_real_uid
);
811 options
.user_hostfile
=
812 tilde_expand_filename(options
.user_hostfile
, original_real_uid
);
813 options
.system_hostfile2
=
814 tilde_expand_filename(options
.system_hostfile2
, original_real_uid
);
815 options
.user_hostfile2
=
816 tilde_expand_filename(options
.user_hostfile2
, original_real_uid
);
818 signal(SIGPIPE
, SIG_IGN
); /* ignore SIGPIPE early */
820 /* Log into the remote system. Never returns if the login fails. */
821 ssh_login(&sensitive_data
, host
, (struct sockaddr
*)&hostaddr
,
824 /* We no longer need the private host keys. Clear them now. */
825 if (sensitive_data
.nkeys
!= 0) {
826 for (i
= 0; i
< sensitive_data
.nkeys
; i
++) {
827 if (sensitive_data
.keys
[i
] != NULL
) {
828 /* Destroys contents safely */
829 debug3("clear hostkey %d", i
);
830 key_free(sensitive_data
.keys
[i
]);
831 sensitive_data
.keys
[i
] = NULL
;
834 xfree(sensitive_data
.keys
);
836 for (i
= 0; i
< options
.num_identity_files
; i
++) {
837 if (options
.identity_files
[i
]) {
838 xfree(options
.identity_files
[i
]);
839 options
.identity_files
[i
] = NULL
;
841 if (options
.identity_keys
[i
]) {
842 key_free(options
.identity_keys
[i
]);
843 options
.identity_keys
[i
] = NULL
;
847 exit_status
= compat20
? ssh_session2() : ssh_session();
850 if (options
.control_path
!= NULL
&& muxserver_sock
!= -1)
851 unlink(options
.control_path
);
854 * Send SIGHUP to proxy command if used. We don't wait() in
855 * case it hangs and instead rely on init to reap the child
857 if (proxy_command_pid
> 1)
858 kill(proxy_command_pid
, SIGHUP
);
863 /* Callback for remote forward global requests */
865 ssh_confirm_remote_forward(int type
, u_int32_t seq
, void *ctxt
)
867 Forward
*rfwd
= (Forward
*)ctxt
;
869 debug("remote forward %s for: listen %d, connect %s:%d",
870 type
== SSH2_MSG_REQUEST_SUCCESS
? "success" : "failure",
871 rfwd
->listen_port
, rfwd
->connect_host
, rfwd
->connect_port
);
872 if (type
== SSH2_MSG_REQUEST_FAILURE
) {
873 if (options
.exit_on_forward_failure
)
874 fatal("Error: remote port forwarding failed for "
875 "listen port %d", rfwd
->listen_port
);
877 logit("Warning: remote port forwarding failed for "
878 "listen port %d", rfwd
->listen_port
);
880 if (++remote_forward_confirms_received
== options
.num_remote_forwards
) {
881 debug("All remote forwarding requests processed");
882 if (fork_after_authentication_flag
) {
883 fork_after_authentication_flag
= 0;
884 if (daemon(1, 1) < 0)
885 fatal("daemon() failed: %.200s",
892 ssh_init_forwarding(void)
897 /* Initiate local TCP/IP port forwardings. */
898 for (i
= 0; i
< options
.num_local_forwards
; i
++) {
899 debug("Local connections to %.200s:%d forwarded to remote "
901 (options
.local_forwards
[i
].listen_host
== NULL
) ?
902 (options
.gateway_ports
? "*" : "LOCALHOST") :
903 options
.local_forwards
[i
].listen_host
,
904 options
.local_forwards
[i
].listen_port
,
905 options
.local_forwards
[i
].connect_host
,
906 options
.local_forwards
[i
].connect_port
);
907 success
+= channel_setup_local_fwd_listener(
908 options
.local_forwards
[i
].listen_host
,
909 options
.local_forwards
[i
].listen_port
,
910 options
.local_forwards
[i
].connect_host
,
911 options
.local_forwards
[i
].connect_port
,
912 options
.gateway_ports
);
914 if (i
> 0 && success
!= i
&& options
.exit_on_forward_failure
)
915 fatal("Could not request local forwarding.");
916 if (i
> 0 && success
== 0)
917 error("Could not request local forwarding.");
919 /* Initiate remote TCP/IP port forwardings. */
920 for (i
= 0; i
< options
.num_remote_forwards
; i
++) {
921 debug("Remote connections from %.200s:%d forwarded to "
922 "local address %.200s:%d",
923 (options
.remote_forwards
[i
].listen_host
== NULL
) ?
924 "LOCALHOST" : options
.remote_forwards
[i
].listen_host
,
925 options
.remote_forwards
[i
].listen_port
,
926 options
.remote_forwards
[i
].connect_host
,
927 options
.remote_forwards
[i
].connect_port
);
928 if (channel_request_remote_forwarding(
929 options
.remote_forwards
[i
].listen_host
,
930 options
.remote_forwards
[i
].listen_port
,
931 options
.remote_forwards
[i
].connect_host
,
932 options
.remote_forwards
[i
].connect_port
) < 0) {
933 if (options
.exit_on_forward_failure
)
934 fatal("Could not request remote forwarding.");
936 logit("Warning: Could not request remote "
939 client_register_global_confirm(ssh_confirm_remote_forward
,
940 &options
.remote_forwards
[i
]);
943 /* Initiate tunnel forwarding. */
944 if (options
.tun_open
!= SSH_TUNMODE_NO
) {
945 if (client_request_tun_fwd(options
.tun_open
,
946 options
.tun_local
, options
.tun_remote
) == -1) {
947 if (options
.exit_on_forward_failure
)
948 fatal("Could not request tunnel forwarding.");
950 error("Could not request tunnel forwarding.");
956 check_agent_present(void)
958 if (options
.forward_agent
) {
959 /* Clear agent forwarding if we don't have an agent. */
960 if (!ssh_agent_present())
961 options
.forward_agent
= 0;
975 /* Enable compression if requested. */
976 if (options
.compression
) {
977 debug("Requesting compression at level %d.",
978 options
.compression_level
);
980 if (options
.compression_level
< 1 ||
981 options
.compression_level
> 9)
982 fatal("Compression level must be from 1 (fast) to "
985 /* Send the request. */
986 packet_start(SSH_CMSG_REQUEST_COMPRESSION
);
987 packet_put_int(options
.compression_level
);
990 type
= packet_read();
991 if (type
== SSH_SMSG_SUCCESS
)
992 packet_start_compression(options
.compression_level
);
993 else if (type
== SSH_SMSG_FAILURE
)
994 logit("Warning: Remote host refused compression.");
996 packet_disconnect("Protocol error waiting for "
997 "compression response.");
999 /* Allocate a pseudo tty if appropriate. */
1001 debug("Requesting pty.");
1003 /* Start the packet. */
1004 packet_start(SSH_CMSG_REQUEST_PTY
);
1006 /* Store TERM in the packet. There is no limit on the
1007 length of the string. */
1008 cp
= getenv("TERM");
1011 packet_put_cstring(cp
);
1013 /* Store window size in the packet. */
1014 if (ioctl(fileno(stdin
), TIOCGWINSZ
, &ws
) < 0)
1015 memset(&ws
, 0, sizeof(ws
));
1016 packet_put_int((u_int
)ws
.ws_row
);
1017 packet_put_int((u_int
)ws
.ws_col
);
1018 packet_put_int((u_int
)ws
.ws_xpixel
);
1019 packet_put_int((u_int
)ws
.ws_ypixel
);
1021 /* Store tty modes in the packet. */
1022 tty_make_modes(fileno(stdin
), NULL
);
1024 /* Send the packet, and wait for it to leave. */
1026 packet_write_wait();
1028 /* Read response from the server. */
1029 type
= packet_read();
1030 if (type
== SSH_SMSG_SUCCESS
) {
1033 } else if (type
== SSH_SMSG_FAILURE
)
1034 logit("Warning: Remote host failed or refused to "
1035 "allocate a pseudo tty.");
1037 packet_disconnect("Protocol error waiting for pty "
1038 "request response.");
1040 /* Request X11 forwarding if enabled and DISPLAY is set. */
1041 display
= getenv("DISPLAY");
1042 if (options
.forward_x11
&& display
!= NULL
) {
1044 /* Get reasonable local authentication information. */
1045 client_x11_get_proto(display
, options
.xauth_location
,
1046 options
.forward_x11_trusted
, &proto
, &data
);
1047 /* Request forwarding with authentication spoofing. */
1048 debug("Requesting X11 forwarding with authentication "
1050 x11_request_forwarding_with_spoofing(0, display
, proto
, data
);
1052 /* Read response from the server. */
1053 type
= packet_read();
1054 if (type
== SSH_SMSG_SUCCESS
) {
1056 } else if (type
== SSH_SMSG_FAILURE
) {
1057 logit("Warning: Remote host denied X11 forwarding.");
1059 packet_disconnect("Protocol error waiting for X11 "
1063 /* Tell the packet module whether this is an interactive session. */
1064 packet_set_interactive(interactive
);
1066 /* Request authentication agent forwarding if appropriate. */
1067 check_agent_present();
1069 if (options
.forward_agent
) {
1070 debug("Requesting authentication agent forwarding.");
1071 auth_request_forwarding();
1073 /* Read response from the server. */
1074 type
= packet_read();
1076 if (type
!= SSH_SMSG_SUCCESS
)
1077 logit("Warning: Remote host denied authentication agent forwarding.");
1080 /* Initiate port forwardings. */
1081 ssh_init_forwarding();
1083 /* Execute a local command */
1084 if (options
.local_command
!= NULL
&&
1085 options
.permit_local_command
)
1086 ssh_local_cmd(options
.local_command
);
1089 * If requested and we are not interested in replies to remote
1090 * forwarding requests, then let ssh continue in the background.
1092 if (fork_after_authentication_flag
&&
1093 (!options
.exit_on_forward_failure
||
1094 options
.num_remote_forwards
== 0)) {
1095 fork_after_authentication_flag
= 0;
1096 if (daemon(1, 1) < 0)
1097 fatal("daemon() failed: %.200s", strerror(errno
));
1101 * If a command was specified on the command line, execute the
1102 * command now. Otherwise request the server to start a shell.
1104 if (buffer_len(&command
) > 0) {
1105 int len
= buffer_len(&command
);
1108 debug("Sending command: %.*s", len
,
1109 (u_char
*)buffer_ptr(&command
));
1110 packet_start(SSH_CMSG_EXEC_CMD
);
1111 packet_put_string(buffer_ptr(&command
), buffer_len(&command
));
1113 packet_write_wait();
1115 debug("Requesting shell.");
1116 packet_start(SSH_CMSG_EXEC_SHELL
);
1118 packet_write_wait();
1121 /* Enter the interactive session. */
1122 return client_loop(have_tty
, tty_flag
?
1123 options
.escape_char
: SSH_ESCAPECHAR_NONE
, 0);
1126 /* request pty/x11/agent/tcpfwd/shell for channel */
1128 ssh_session2_setup(int id
, void *arg
)
1130 extern char **environ
;
1131 const char *display
;
1132 int interactive
= tty_flag
;
1134 display
= getenv("DISPLAY");
1135 if (options
.forward_x11
&& display
!= NULL
) {
1137 /* Get reasonable local authentication information. */
1138 client_x11_get_proto(display
, options
.xauth_location
,
1139 options
.forward_x11_trusted
, &proto
, &data
);
1140 /* Request forwarding with authentication spoofing. */
1141 debug("Requesting X11 forwarding with authentication "
1143 x11_request_forwarding_with_spoofing(id
, display
, proto
, data
);
1145 /* XXX wait for reply */
1148 check_agent_present();
1149 if (options
.forward_agent
) {
1150 debug("Requesting authentication agent forwarding.");
1151 channel_request_start(id
, "auth-agent-req@openssh.com", 0);
1155 client_session2_setup(id
, tty_flag
, subsystem_flag
, getenv("TERM"),
1156 NULL
, fileno(stdin
), &command
, environ
);
1158 packet_set_interactive(interactive
);
1161 /* open new channel for a session */
1163 ssh_session2_open(void)
1166 int window
, packetmax
, in
, out
, err
;
1168 if (stdin_null_flag
) {
1169 in
= open(_PATH_DEVNULL
, O_RDONLY
);
1171 in
= dup(STDIN_FILENO
);
1173 out
= dup(STDOUT_FILENO
);
1174 err
= dup(STDERR_FILENO
);
1176 if (in
< 0 || out
< 0 || err
< 0)
1177 fatal("dup() in/out/err failed");
1179 /* enable nonblocking unless tty */
1187 window
= CHAN_SES_WINDOW_DEFAULT
;
1188 packetmax
= CHAN_SES_PACKET_DEFAULT
;
1194 "session", SSH_CHANNEL_OPENING
, in
, out
, err
,
1195 window
, packetmax
, CHAN_EXTENDED_WRITE
,
1196 "client-session", /*nonblock*/0);
1198 debug3("ssh_session2_open: channel_new: %d", c
->self
);
1200 channel_send_open(c
->self
);
1202 channel_register_open_confirm(c
->self
,
1203 ssh_session2_setup
, NULL
);
1213 /* XXX should be pre-session */
1214 ssh_init_forwarding();
1216 if (!no_shell_flag
|| (datafellows
& SSH_BUG_DUMMYCHAN
))
1217 id
= ssh_session2_open();
1219 /* If we don't expect to open a new session, then disallow it */
1220 if (options
.control_master
== SSHCTL_MASTER_NO
) {
1221 debug("Requesting no-more-sessions@openssh.com");
1222 packet_start(SSH2_MSG_GLOBAL_REQUEST
);
1223 packet_put_cstring("no-more-sessions@openssh.com");
1228 /* Execute a local command */
1229 if (options
.local_command
!= NULL
&&
1230 options
.permit_local_command
)
1231 ssh_local_cmd(options
.local_command
);
1233 /* Start listening for multiplex clients */
1236 /* If requested, let ssh continue in the background. */
1237 if (fork_after_authentication_flag
) {
1238 fork_after_authentication_flag
= 0;
1239 if (daemon(1, 1) < 0)
1240 fatal("daemon() failed: %.200s", strerror(errno
));
1243 return client_loop(tty_flag
, tty_flag
?
1244 options
.escape_char
: SSH_ESCAPECHAR_NONE
, id
);
1248 load_public_identity_files(void)
1250 char *filename
, *cp
, thishost
[NI_MAXHOST
];
1251 char *pwdir
= NULL
, *pwname
= NULL
;
1258 if (options
.smartcard_device
!= NULL
&&
1259 options
.num_identity_files
< SSH_MAX_IDENTITY_FILES
&&
1260 (keys
= sc_get_keys(options
.smartcard_device
, NULL
)) != NULL
) {
1262 for (i
= 0; keys
[i
] != NULL
; i
++) {
1264 memmove(&options
.identity_files
[1],
1265 &options
.identity_files
[0],
1266 sizeof(char *) * (SSH_MAX_IDENTITY_FILES
- 1));
1267 memmove(&options
.identity_keys
[1],
1268 &options
.identity_keys
[0],
1269 sizeof(Key
*) * (SSH_MAX_IDENTITY_FILES
- 1));
1270 options
.num_identity_files
++;
1271 options
.identity_keys
[0] = keys
[i
];
1272 options
.identity_files
[0] = sc_get_key_label(keys
[i
]);
1274 if (options
.num_identity_files
> SSH_MAX_IDENTITY_FILES
)
1275 options
.num_identity_files
= SSH_MAX_IDENTITY_FILES
;
1279 #endif /* SMARTCARD */
1280 if ((pw
= getpwuid(original_real_uid
)) == NULL
)
1281 fatal("load_public_identity_files: getpwuid failed");
1282 pwname
= xstrdup(pw
->pw_name
);
1283 pwdir
= xstrdup(pw
->pw_dir
);
1284 if (gethostname(thishost
, sizeof(thishost
)) == -1)
1285 fatal("load_public_identity_files: gethostname: %s",
1287 for (; i
< options
.num_identity_files
; i
++) {
1288 cp
= tilde_expand_filename(options
.identity_files
[i
],
1290 filename
= percent_expand(cp
, "d", pwdir
,
1291 "u", pwname
, "l", thishost
, "h", host
,
1292 "r", options
.user
, (char *)NULL
);
1294 public = key_load_public(filename
, NULL
);
1295 debug("identity file %s type %d", filename
,
1296 public ? public->type
: -1);
1297 xfree(options
.identity_files
[i
]);
1298 options
.identity_files
[i
] = filename
;
1299 options
.identity_keys
[i
] = public;
1301 bzero(pwname
, strlen(pwname
));
1303 bzero(pwdir
, strlen(pwdir
));