blob: 68ce1717701719f48dde2acd1c7a30be537e496b [file] [log] [blame]
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001/*
Damien Miller95def091999-11-25 00:26:21 +11002 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4 * All rights reserved
Damien Miller95def091999-11-25 00:26:21 +11005 * 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.
8 *
Damien Millere4340be2000-09-16 13:29:08 +11009 * 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".
14 *
15 * Copyright (c) 1999 Niels Provos. All rights reserved.
16 *
17 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
18 * in Canada (German citizen).
19 *
20 * Redistribution and use in source and binary forms, with or without
21 * modification, are permitted provided that the following conditions
22 * are met:
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.
28 *
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.
Damien Miller95def091999-11-25 00:26:21 +110039 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100040
41#include "includes.h"
Ben Lindstrom92d4a022001-04-13 04:44:37 +000042RCSID("$OpenBSD: ssh.c,v 1.114 2001/04/13 01:26:17 stevesk Exp $");
Damien Millereba71ba2000-04-29 23:57:08 +100043
44#include <openssl/evp.h>
Damien Miller0bc1bd82000-11-13 22:57:25 +110045#include <openssl/err.h>
Damien Millerd4a8b7e1999-10-27 13:42:43 +100046
Damien Millerd4a8b7e1999-10-27 13:42:43 +100047#include "ssh.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000048#include "ssh1.h"
Damien Miller1383bd82000-04-06 12:32:37 +100049#include "ssh2.h"
50#include "compat.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000051#include "cipher.h"
52#include "xmalloc.h"
53#include "packet.h"
54#include "buffer.h"
55#include "uidswap.h"
Damien Millerb38eff82000-04-01 11:09:21 +100056#include "channels.h"
Damien Millereba71ba2000-04-29 23:57:08 +100057#include "key.h"
Damien Miller994cf142000-07-21 10:19:44 +100058#include "authfd.h"
Damien Millereba71ba2000-04-29 23:57:08 +100059#include "authfile.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000060#include "pathnames.h"
Ben Lindstrombf555ba2001-01-18 02:04:35 +000061#include "clientloop.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000062#include "log.h"
63#include "readconf.h"
64#include "sshconnect.h"
65#include "tildexpand.h"
Ben Lindstrom1e7d3062001-02-09 02:36:43 +000066#include "dispatch.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000067#include "misc.h"
Ben Lindstrom06b33aa2001-02-15 03:01:59 +000068#include "kex.h"
69#include "mac.h"
Damien Millerd4a8b7e1999-10-27 13:42:43 +100070
Damien Miller3f905871999-11-15 17:10:57 +110071#ifdef HAVE___PROGNAME
72extern char *__progname;
Ben Lindstrom49a79c02000-11-17 03:47:20 +000073#else
74char *__progname;
75#endif
Damien Miller3f905871999-11-15 17:10:57 +110076
Damien Miller34132e52000-01-14 15:45:46 +110077/* 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. */
Damien Miller7d80e342000-01-19 14:36:49 +110079#ifdef IPV4_DEFAULT
80int IPv4or6 = AF_INET;
81#else
Damien Miller34132e52000-01-14 15:45:46 +110082int IPv4or6 = AF_UNSPEC;
Damien Miller7d80e342000-01-19 14:36:49 +110083#endif
Damien Miller34132e52000-01-14 15:45:46 +110084
Damien Miller95def091999-11-25 00:26:21 +110085/* Flag indicating whether debug mode is on. This can be set on the command line. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100086int debug_flag = 0;
87
Damien Miller78928792000-04-12 20:17:38 +100088/* Flag indicating whether a tty should be allocated */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100089int tty_flag = 0;
Ben Lindstrom4dccfa52000-12-28 16:40:05 +000090int no_tty_flag = 0;
91int force_tty_flag = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +100092
Damien Miller1383bd82000-04-06 12:32:37 +100093/* don't exec a shell */
94int no_shell_flag = 0;
Damien Miller1383bd82000-04-06 12:32:37 +100095
Damien Miller5428f641999-11-25 11:54:57 +110096/*
97 * Flag indicating that nothing should be read from stdin. This can be set
98 * on the command line.
99 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000100int stdin_null_flag = 0;
101
Damien Miller5428f641999-11-25 11:54:57 +1100102/*
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
105 * background.
106 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000107int fork_after_authentication_flag = 0;
108
Damien Miller5428f641999-11-25 11:54:57 +1100109/*
110 * General data structure for command line options and options configurable
111 * in configuration files. See readconf.h.
112 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000113Options options;
114
Damien Miller5428f641999-11-25 11:54:57 +1100115/*
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.
119 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000120char *host;
121
122/* socket address the host resolves to */
Damien Miller34132e52000-01-14 15:45:46 +1100123struct sockaddr_storage hostaddr;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000124
Damien Miller5428f641999-11-25 11:54:57 +1100125/*
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.
130 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000131volatile int received_window_change_signal = 0;
132
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000133/* Private host keys. */
134struct {
135 Key **keys;
136 int nkeys;
137} sensitive_data;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000138
139/* Original real UID. */
140uid_t original_real_uid;
141
Damien Miller1383bd82000-04-06 12:32:37 +1000142/* command to be executed */
143Buffer command;
144
Damien Miller832562e2001-01-30 09:30:01 +1100145/* Should we execute a command or invoke a subsystem? */
146int subsystem_flag = 0;
147
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000148/* Prints a help message to the user. This function never returns. */
149
150void
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000151usage(void)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000152{
Kevin Stevesec84dc12000-12-13 17:45:15 +0000153 fprintf(stderr, "Usage: %s [options] host [command]\n", __progname);
Damien Miller95def091999-11-25 00:26:21 +1100154 fprintf(stderr, "Options:\n");
155 fprintf(stderr, " -l user Log in using this user name.\n");
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000156 fprintf(stderr, " -n Redirect input from " _PATH_DEVNULL ".\n");
Damien Millerb1715dc2000-05-30 13:44:51 +1000157 fprintf(stderr, " -A Enable authentication agent forwarding.\n");
Damien Miller95def091999-11-25 00:26:21 +1100158 fprintf(stderr, " -a Disable authentication agent forwarding.\n");
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000159#ifdef AFS
Damien Miller95def091999-11-25 00:26:21 +1100160 fprintf(stderr, " -k Disable Kerberos ticket and AFS token forwarding.\n");
161#endif /* AFS */
Kevin Stevesef4eea92001-02-05 12:42:17 +0000162 fprintf(stderr, " -X Enable X11 connection forwarding.\n");
Damien Miller95def091999-11-25 00:26:21 +1100163 fprintf(stderr, " -x Disable X11 connection forwarding.\n");
Ben Lindstrom0ab2a012001-03-05 06:45:21 +0000164 fprintf(stderr, " -i file Identity for public key authentication "
165 "(default: ~/.ssh/identity)\n");
Damien Miller95def091999-11-25 00:26:21 +1100166 fprintf(stderr, " -t Tty; allocate a tty even if command is given.\n");
Damien Miller1383bd82000-04-06 12:32:37 +1000167 fprintf(stderr, " -T Do not allocate a tty.\n");
Damien Miller95def091999-11-25 00:26:21 +1100168 fprintf(stderr, " -v Verbose; display verbose debugging messages.\n");
Damien Millere4340be2000-09-16 13:29:08 +1100169 fprintf(stderr, " Multiple -v increases verbosity.\n");
Damien Miller95def091999-11-25 00:26:21 +1100170 fprintf(stderr, " -V Display version number only.\n");
171 fprintf(stderr, " -P Don't allocate a privileged port.\n");
172 fprintf(stderr, " -q Quiet; don't display any warning messages.\n");
173 fprintf(stderr, " -f Fork into background after authentication.\n");
174 fprintf(stderr, " -e char Set escape character; ``none'' = disable (default: ~).\n");
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000175
Damien Miller95def091999-11-25 00:26:21 +1100176 fprintf(stderr, " -c cipher Select encryption algorithm: "
Ben Lindstrom0ab2a012001-03-05 06:45:21 +0000177 "``3des'', ``blowfish''\n");
Ben Lindstrom3d73a342001-03-05 07:39:01 +0000178 fprintf(stderr, " -m macs Specify MAC algorithms for protocol version 2.\n");
Damien Miller95def091999-11-25 00:26:21 +1100179 fprintf(stderr, " -p port Connect to this port. Server must be on the same port.\n");
180 fprintf(stderr, " -L listen-port:host:port Forward local port to remote address\n");
181 fprintf(stderr, " -R listen-port:host:port Forward remote port to local address\n");
Kevin Stevesec84dc12000-12-13 17:45:15 +0000182 fprintf(stderr, " These cause %s to listen for connections on a port, and\n", __progname);
Damien Miller95def091999-11-25 00:26:21 +1100183 fprintf(stderr, " forward them to the other side by connecting to host:port.\n");
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000184 fprintf(stderr, " -D port Dynamically forward local port to multiple remote addresses.\n");
Ben Lindstrom6fa9d102001-04-11 23:08:17 +0000185 fprintf(stderr, " Allows %s to act as an application-layer proxy.\n",
186 __progname);
187 fprintf(stderr, " Protocols supported: SOCKS4, SOCKS5, HTTPS\n");
Damien Miller95def091999-11-25 00:26:21 +1100188 fprintf(stderr, " -C Enable compression.\n");
Damien Miller1383bd82000-04-06 12:32:37 +1000189 fprintf(stderr, " -N Do not execute a shell or command.\n");
Damien Miller95def091999-11-25 00:26:21 +1100190 fprintf(stderr, " -g Allow remote hosts to connect to forwarded ports.\n");
Ben Lindstrom1e7d3062001-02-09 02:36:43 +0000191 fprintf(stderr, " -1 Force protocol version 1.\n");
192 fprintf(stderr, " -2 Force protocol version 2.\n");
Damien Miller34132e52000-01-14 15:45:46 +1100193 fprintf(stderr, " -4 Use IPv4 only.\n");
194 fprintf(stderr, " -6 Use IPv6 only.\n");
Damien Miller95def091999-11-25 00:26:21 +1100195 fprintf(stderr, " -o 'option' Process the option as if it was read from a configuration file.\n");
Damien Miller832562e2001-01-30 09:30:01 +1100196 fprintf(stderr, " -s Invoke command (mandatory) as SSH2 subsystem.\n");
Damien Miller95def091999-11-25 00:26:21 +1100197 exit(1);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000198}
199
Damien Miller95def091999-11-25 00:26:21 +1100200/*
201 * Connects to the given host using rsh (or prints an error message and exits
202 * if rsh is not available). This function never returns.
203 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000204void
Damien Miller95def091999-11-25 00:26:21 +1100205rsh_connect(char *host, char *user, Buffer * command)
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000206{
Damien Miller95def091999-11-25 00:26:21 +1100207 char *args[10];
208 int i;
209
210 log("Using rsh. WARNING: Connection will not be encrypted.");
211 /* Build argument list for rsh. */
212 i = 0;
213 args[i++] = _PATH_RSH;
214 /* host may have to come after user on some systems */
215 args[i++] = host;
216 if (user) {
217 args[i++] = "-l";
218 args[i++] = user;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000219 }
Damien Miller95def091999-11-25 00:26:21 +1100220 if (buffer_len(command) > 0) {
221 buffer_append(command, "\0", 1);
222 args[i++] = buffer_ptr(command);
223 }
224 args[i++] = NULL;
225 if (debug_flag) {
226 for (i = 0; args[i]; i++) {
227 if (i != 0)
228 fprintf(stderr, " ");
229 fprintf(stderr, "%s", args[i]);
230 }
231 fprintf(stderr, "\n");
232 }
233 execv(_PATH_RSH, args);
234 perror(_PATH_RSH);
235 exit(1);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000236}
237
Damien Miller0bc1bd82000-11-13 22:57:25 +1100238int ssh_session(void);
239int ssh_session2(void);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000240void load_public_identity_files(void);
Damien Miller1383bd82000-04-06 12:32:37 +1000241
Damien Miller95def091999-11-25 00:26:21 +1100242/*
243 * Main program for the ssh client.
244 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000245int
246main(int ac, char **av)
247{
Damien Miller1383bd82000-04-06 12:32:37 +1000248 int i, opt, optind, exit_status, ok;
Damien Milleraae6c611999-12-06 11:47:28 +1100249 u_short fwd_port, fwd_host_port;
Ben Lindstrom19066a12001-04-12 23:39:26 +0000250 char *optarg, *cp, buf[256];
Damien Miller95def091999-11-25 00:26:21 +1100251 struct stat st;
Ben Lindstrom086cf212001-03-05 05:56:40 +0000252 struct passwd *pw;
Damien Miller1383bd82000-04-06 12:32:37 +1000253 int dummy;
Damien Miller95def091999-11-25 00:26:21 +1100254 uid_t original_effective_uid;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000255
Ben Lindstrom49a79c02000-11-17 03:47:20 +0000256 __progname = get_progname(av[0]);
Damien Millerf9b625c2000-07-09 22:42:32 +1000257 init_rng();
258
Damien Miller5428f641999-11-25 11:54:57 +1100259 /*
260 * Save the original real uid. It will be needed later (uid-swapping
261 * may clobber the real uid).
262 */
Damien Miller95def091999-11-25 00:26:21 +1100263 original_real_uid = getuid();
264 original_effective_uid = geteuid();
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000265
Damien Miller05dd7952000-10-01 00:42:48 +1100266#ifdef HAVE_SETRLIMIT
Damien Miller95def091999-11-25 00:26:21 +1100267 /* If we are installed setuid root be careful to not drop core. */
268 if (original_real_uid != original_effective_uid) {
269 struct rlimit rlim;
270 rlim.rlim_cur = rlim.rlim_max = 0;
271 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
272 fatal("setrlimit failed: %.100s", strerror(errno));
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000273 }
Damien Millerbac2d8a2000-09-05 16:13:06 +1100274#endif
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000275 /* Get user data. */
276 pw = getpwuid(original_real_uid);
277 if (!pw) {
278 log("You don't exist, go away!");
279 exit(1);
280 }
281 /* Take a copy of the returned structure. */
282 pw = pwcopy(pw);
283
Damien Miller5428f641999-11-25 11:54:57 +1100284 /*
285 * Use uid-swapping to give up root privileges for the duration of
286 * option processing. We will re-instantiate the rights when we are
287 * ready to create the privileged port, and will permanently drop
288 * them when the port has been created (actually, when the connection
289 * has been made, as we may need to create the port several times).
290 */
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000291 temporarily_use_uid(pw);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000292
Damien Miller5428f641999-11-25 11:54:57 +1100293 /*
294 * Set our umask to something reasonable, as some files are created
295 * with the default umask. This will make them world-readable but
296 * writable only by the owner, which is ok for all files for which we
297 * don't set the modes explicitly.
298 */
Damien Miller95def091999-11-25 00:26:21 +1100299 umask(022);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000300
Damien Miller95def091999-11-25 00:26:21 +1100301 /* Initialize option structure to indicate that no values have been set. */
302 initialize_options(&options);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000303
Damien Miller95def091999-11-25 00:26:21 +1100304 /* Parse command-line arguments. */
305 host = NULL;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000306
Damien Miller95def091999-11-25 00:26:21 +1100307 for (optind = 1; optind < ac; optind++) {
308 if (av[optind][0] != '-') {
309 if (host)
310 break;
311 if ((cp = strchr(av[optind], '@'))) {
Damien Miller4af51302000-04-16 11:18:38 +1000312 if(cp == av[optind])
313 usage();
Damien Miller95def091999-11-25 00:26:21 +1100314 options.user = av[optind];
315 *cp = '\0';
316 host = ++cp;
317 } else
318 host = av[optind];
319 continue;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000320 }
Damien Miller95def091999-11-25 00:26:21 +1100321 opt = av[optind][1];
322 if (!opt)
323 usage();
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000324 if (strchr("eilcmpLRDo", opt)) { /* options with arguments */
Damien Miller95def091999-11-25 00:26:21 +1100325 optarg = av[optind] + 2;
326 if (strcmp(optarg, "") == 0) {
327 if (optind >= ac - 1)
328 usage();
329 optarg = av[++optind];
330 }
331 } else {
332 if (av[optind][2])
333 usage();
334 optarg = NULL;
335 }
336 switch (opt) {
Ben Lindstrom1e7d3062001-02-09 02:36:43 +0000337 case '1':
338 options.protocol = SSH_PROTO_1;
339 break;
Damien Miller4af51302000-04-16 11:18:38 +1000340 case '2':
341 options.protocol = SSH_PROTO_2;
342 break;
Damien Miller34132e52000-01-14 15:45:46 +1100343 case '4':
344 IPv4or6 = AF_INET;
345 break;
Damien Miller34132e52000-01-14 15:45:46 +1100346 case '6':
347 IPv4or6 = AF_INET6;
348 break;
Damien Miller95def091999-11-25 00:26:21 +1100349 case 'n':
350 stdin_null_flag = 1;
351 break;
Damien Miller95def091999-11-25 00:26:21 +1100352 case 'f':
353 fork_after_authentication_flag = 1;
354 stdin_null_flag = 1;
355 break;
Damien Miller95def091999-11-25 00:26:21 +1100356 case 'x':
357 options.forward_x11 = 0;
358 break;
Damien Miller95def091999-11-25 00:26:21 +1100359 case 'X':
360 options.forward_x11 = 1;
361 break;
Damien Miller95def091999-11-25 00:26:21 +1100362 case 'g':
363 options.gateway_ports = 1;
364 break;
Damien Miller95def091999-11-25 00:26:21 +1100365 case 'P':
366 options.use_privileged_port = 0;
367 break;
Damien Miller95def091999-11-25 00:26:21 +1100368 case 'a':
369 options.forward_agent = 0;
370 break;
Damien Millerb1715dc2000-05-30 13:44:51 +1000371 case 'A':
372 options.forward_agent = 1;
373 break;
Damien Miller95def091999-11-25 00:26:21 +1100374#ifdef AFS
375 case 'k':
376 options.kerberos_tgt_passing = 0;
377 options.afs_token_passing = 0;
378 break;
379#endif
380 case 'i':
381 if (stat(optarg, &st) < 0) {
382 fprintf(stderr, "Warning: Identity file %s does not exist.\n",
Damien Miller0bc1bd82000-11-13 22:57:25 +1100383 optarg);
Damien Miller95def091999-11-25 00:26:21 +1100384 break;
385 }
386 if (options.num_identity_files >= SSH_MAX_IDENTITY_FILES)
387 fatal("Too many identity files specified (max %d)",
Damien Miller0bc1bd82000-11-13 22:57:25 +1100388 SSH_MAX_IDENTITY_FILES);
389 options.identity_files[options.num_identity_files++] = xstrdup(optarg);
Damien Miller95def091999-11-25 00:26:21 +1100390 break;
Damien Miller95def091999-11-25 00:26:21 +1100391 case 't':
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000392 if (tty_flag)
393 force_tty_flag = 1;
Damien Miller95def091999-11-25 00:26:21 +1100394 tty_flag = 1;
395 break;
Damien Miller95def091999-11-25 00:26:21 +1100396 case 'v':
Damien Millere4340be2000-09-16 13:29:08 +1100397 if (0 == debug_flag) {
398 debug_flag = 1;
399 options.log_level = SYSLOG_LEVEL_DEBUG1;
400 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
401 options.log_level++;
402 break;
403 } else {
Ben Lindstrom6df8ef42001-03-05 07:47:23 +0000404 fatal("Too high debugging level.");
Damien Millere4340be2000-09-16 13:29:08 +1100405 }
406 /* fallthrough */
Damien Miller95def091999-11-25 00:26:21 +1100407 case 'V':
Damien Miller225736c2001-02-19 21:51:08 +1100408 fprintf(stderr,
409 "%s, SSH protocols %d.%d/%d.%d, OpenSSL 0x%8.8lx\n",
Damien Miller78928792000-04-12 20:17:38 +1000410 SSH_VERSION,
411 PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
Damien Miller225736c2001-02-19 21:51:08 +1100412 PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2,
413 SSLeay());
Damien Miller95def091999-11-25 00:26:21 +1100414 if (opt == 'V')
415 exit(0);
Damien Miller95def091999-11-25 00:26:21 +1100416 break;
Damien Miller95def091999-11-25 00:26:21 +1100417 case 'q':
418 options.log_level = SYSLOG_LEVEL_QUIET;
419 break;
Damien Miller95def091999-11-25 00:26:21 +1100420 case 'e':
421 if (optarg[0] == '^' && optarg[2] == 0 &&
Ben Lindstrom46c16222000-12-22 01:43:59 +0000422 (u_char) optarg[1] >= 64 && (u_char) optarg[1] < 128)
423 options.escape_char = (u_char) optarg[1] & 31;
Damien Miller95def091999-11-25 00:26:21 +1100424 else if (strlen(optarg) == 1)
Ben Lindstrom46c16222000-12-22 01:43:59 +0000425 options.escape_char = (u_char) optarg[0];
Damien Miller95def091999-11-25 00:26:21 +1100426 else if (strcmp(optarg, "none") == 0)
427 options.escape_char = -2;
428 else {
429 fprintf(stderr, "Bad escape character '%s'.\n", optarg);
430 exit(1);
431 }
432 break;
Damien Miller95def091999-11-25 00:26:21 +1100433 case 'c':
Damien Millereba71ba2000-04-29 23:57:08 +1000434 if (ciphers_valid(optarg)) {
435 /* SSH2 only */
436 options.ciphers = xstrdup(optarg);
Damien Miller30c3d422000-05-09 11:02:59 +1000437 options.cipher = SSH_CIPHER_ILLEGAL;
Damien Millereba71ba2000-04-29 23:57:08 +1000438 } else {
439 /* SSH1 only */
Damien Millere39cacc2000-11-29 12:18:44 +1100440 options.cipher = cipher_number(optarg);
441 if (options.cipher == -1) {
Damien Millereba71ba2000-04-29 23:57:08 +1000442 fprintf(stderr, "Unknown cipher type '%s'\n", optarg);
443 exit(1);
444 }
Damien Millere39cacc2000-11-29 12:18:44 +1100445 if (options.cipher == SSH_CIPHER_3DES) {
446 options.ciphers = "3des-cbc";
447 } else if (options.cipher == SSH_CIPHER_BLOWFISH) {
448 options.ciphers = "blowfish-cbc";
449 } else {
450 options.ciphers = (char *)-1;
451 }
Damien Miller95def091999-11-25 00:26:21 +1100452 }
453 break;
Ben Lindstrom06b33aa2001-02-15 03:01:59 +0000454 case 'm':
455 if (mac_valid(optarg))
456 options.macs = xstrdup(optarg);
457 else {
458 fprintf(stderr, "Unknown mac type '%s'\n", optarg);
459 exit(1);
460 }
461 break;
Damien Miller95def091999-11-25 00:26:21 +1100462 case 'p':
Ben Lindstrom19066a12001-04-12 23:39:26 +0000463 options.port = a2port(optarg);
464 if (options.port == 0) {
Ben Lindstrom146edb92001-04-11 23:06:28 +0000465 fprintf(stderr, "Bad port '%s'\n", optarg);
466 exit(1);
467 }
Damien Miller95def091999-11-25 00:26:21 +1100468 break;
Damien Miller95def091999-11-25 00:26:21 +1100469 case 'l':
470 options.user = optarg;
471 break;
Damien Miller95def091999-11-25 00:26:21 +1100472 case 'R':
Damien Miller34132e52000-01-14 15:45:46 +1100473 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
474 &fwd_host_port) != 3 &&
475 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
476 &fwd_host_port) != 3) {
Damien Miller95def091999-11-25 00:26:21 +1100477 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
478 usage();
479 /* NOTREACHED */
480 }
481 add_remote_forward(&options, fwd_port, buf, fwd_host_port);
482 break;
Damien Miller95def091999-11-25 00:26:21 +1100483 case 'L':
Damien Miller34132e52000-01-14 15:45:46 +1100484 if (sscanf(optarg, "%hu/%255[^/]/%hu", &fwd_port, buf,
485 &fwd_host_port) != 3 &&
486 sscanf(optarg, "%hu:%255[^:]:%hu", &fwd_port, buf,
487 &fwd_host_port) != 3) {
Damien Miller95def091999-11-25 00:26:21 +1100488 fprintf(stderr, "Bad forwarding specification '%s'.\n", optarg);
489 usage();
490 /* NOTREACHED */
491 }
492 add_local_forward(&options, fwd_port, buf, fwd_host_port);
493 break;
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000494
495 case 'D':
Ben Lindstrom19066a12001-04-12 23:39:26 +0000496 fwd_port = a2port(optarg);
497 if (fwd_port == 0) {
498 fprintf(stderr, "Bad dynamic port '%s'\n", optarg);
Ben Lindstrom146edb92001-04-11 23:06:28 +0000499 exit(1);
500 }
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +0000501 add_local_forward(&options, fwd_port, "socks4", 0);
502 break;
503
Damien Miller95def091999-11-25 00:26:21 +1100504 case 'C':
505 options.compression = 1;
506 break;
Damien Miller1383bd82000-04-06 12:32:37 +1000507 case 'N':
508 no_shell_flag = 1;
509 no_tty_flag = 1;
510 break;
Damien Miller1383bd82000-04-06 12:32:37 +1000511 case 'T':
512 no_tty_flag = 1;
513 break;
Damien Miller95def091999-11-25 00:26:21 +1100514 case 'o':
515 dummy = 1;
516 if (process_config_line(&options, host ? host : "", optarg,
517 "command-line", 0, &dummy) != 0)
518 exit(1);
519 break;
Damien Miller832562e2001-01-30 09:30:01 +1100520 case 's':
521 subsystem_flag = 1;
522 break;
Damien Miller95def091999-11-25 00:26:21 +1100523 default:
524 usage();
525 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000526 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000527
Damien Miller95def091999-11-25 00:26:21 +1100528 /* Check that we got a host name. */
529 if (!host)
530 usage();
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000531
Damien Millercb5e44a2000-09-29 12:12:36 +1100532 SSLeay_add_all_algorithms();
Damien Miller0bc1bd82000-11-13 22:57:25 +1100533 ERR_load_crypto_strings();
Damien Millercb5e44a2000-09-29 12:12:36 +1100534
Damien Miller95def091999-11-25 00:26:21 +1100535 /* Initialize the command to execute on remote host. */
536 buffer_init(&command);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000537
Damien Miller5428f641999-11-25 11:54:57 +1100538 /*
539 * Save the command to execute on the remote host in a buffer. There
540 * is no limit on the length of the command, except by the maximum
541 * packet size. Also sets the tty flag if there is no command.
542 */
Damien Miller95def091999-11-25 00:26:21 +1100543 if (optind == ac) {
544 /* No command specified - execute shell on a tty. */
545 tty_flag = 1;
Damien Miller832562e2001-01-30 09:30:01 +1100546 if (subsystem_flag) {
Ben Lindstrom92d4a022001-04-13 04:44:37 +0000547 fprintf(stderr, "You must specify a subsystem to invoke.\n");
Damien Miller832562e2001-01-30 09:30:01 +1100548 usage();
549 }
Damien Miller95def091999-11-25 00:26:21 +1100550 } else {
551 /* A command has been specified. Store it into the
552 buffer. */
553 for (i = optind; i < ac; i++) {
554 if (i > optind)
555 buffer_append(&command, " ", 1);
556 buffer_append(&command, av[i], strlen(av[i]));
557 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000558 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000559
Damien Miller95def091999-11-25 00:26:21 +1100560 /* Cannot fork to background if no command. */
Damien Millercaf6dd62000-08-29 11:33:50 +1100561 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
Damien Miller95def091999-11-25 00:26:21 +1100562 fatal("Cannot fork into background without a command to execute.");
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000563
Damien Miller95def091999-11-25 00:26:21 +1100564 /* Allocate a tty by default if no command specified. */
565 if (buffer_len(&command) == 0)
566 tty_flag = 1;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000567
Ben Lindstromc72745a2000-12-02 19:03:54 +0000568 /* Force no tty*/
569 if (no_tty_flag)
570 tty_flag = 0;
Damien Miller95def091999-11-25 00:26:21 +1100571 /* Do not allocate a tty if stdin is not a tty. */
Ben Lindstrom4dccfa52000-12-28 16:40:05 +0000572 if (!isatty(fileno(stdin)) && !force_tty_flag) {
Damien Miller95def091999-11-25 00:26:21 +1100573 if (tty_flag)
Ben Lindstrom6df8ef42001-03-05 07:47:23 +0000574 log("Pseudo-terminal will not be allocated because stdin is not a terminal.");
Damien Miller95def091999-11-25 00:26:21 +1100575 tty_flag = 0;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000576 }
Damien Miller1383bd82000-04-06 12:32:37 +1000577
Ben Lindstrom8a432f52001-03-05 07:24:46 +0000578 /*
579 * Initialize "log" output. Since we are the client all output
580 * actually goes to stderr.
581 */
Ben Lindstrom2b646522001-04-12 16:16:57 +0000582 log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
583 SYSLOG_FACILITY_USER, 1);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000584
Damien Miller95def091999-11-25 00:26:21 +1100585 /* Read per-user configuration file. */
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000586 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_CONFFILE);
Damien Miller95def091999-11-25 00:26:21 +1100587 read_config_file(buf, host, &options);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000588
Damien Miller95def091999-11-25 00:26:21 +1100589 /* Read systemwide configuration file. */
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000590 read_config_file(_PATH_HOST_CONFIG_FILE, host, &options);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000591
Damien Miller95def091999-11-25 00:26:21 +1100592 /* Fill configuration defaults. */
593 fill_default_options(&options);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000594
Damien Miller95def091999-11-25 00:26:21 +1100595 /* reinit */
Ben Lindstrom8a432f52001-03-05 07:24:46 +0000596 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000597
Damien Miller60bc5172001-03-19 09:38:15 +1100598 seed_rng();
599
Damien Miller95def091999-11-25 00:26:21 +1100600 if (options.user == NULL)
601 options.user = xstrdup(pw->pw_name);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000602
Damien Miller95def091999-11-25 00:26:21 +1100603 if (options.hostname != NULL)
604 host = options.hostname;
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000605
Damien Miller95def091999-11-25 00:26:21 +1100606 /* Disable rhosts authentication if not running as root. */
Damien Millerbac2d8a2000-09-05 16:13:06 +1100607#ifdef HAVE_CYGWIN
608 /* Ignore uid if running under Windows */
609 if (!options.use_privileged_port) {
610#else
Damien Miller95def091999-11-25 00:26:21 +1100611 if (original_effective_uid != 0 || !options.use_privileged_port) {
Damien Millerbac2d8a2000-09-05 16:13:06 +1100612#endif
Kevin Stevesfcec7f82000-12-15 19:55:48 +0000613 debug("Rhosts Authentication disabled, "
614 "originating port will not be trusted.");
Damien Miller95def091999-11-25 00:26:21 +1100615 options.rhosts_authentication = 0;
Damien Miller95def091999-11-25 00:26:21 +1100616 }
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000617
Damien Miller5428f641999-11-25 11:54:57 +1100618 /*
619 * If using rsh has been selected, exec it now (without trying
620 * anything else). Note that we must release privileges first.
621 */
Damien Miller95def091999-11-25 00:26:21 +1100622 if (options.use_rsh) {
Damien Miller5428f641999-11-25 11:54:57 +1100623 /*
624 * Restore our superuser privileges. This must be done
625 * before permanently setting the uid.
626 */
Damien Miller95def091999-11-25 00:26:21 +1100627 restore_uid();
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000628
Damien Miller95def091999-11-25 00:26:21 +1100629 /* Switch to the original uid permanently. */
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000630 permanently_set_uid(pw);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000631
Damien Miller95def091999-11-25 00:26:21 +1100632 /* Execute rsh. */
633 rsh_connect(host, options.user, &command);
634 fatal("rsh_connect returned");
635 }
636 /* Restore our superuser privileges. */
637 restore_uid();
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000638
Kevin Stevesfcec7f82000-12-15 19:55:48 +0000639 /* Open a connection to the remote host. */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000640
Damien Miller95def091999-11-25 00:26:21 +1100641 ok = ssh_connect(host, &hostaddr, options.port,
Kevin Stevesfcec7f82000-12-15 19:55:48 +0000642 options.connection_attempts,
643 original_effective_uid != 0 || !options.use_privileged_port,
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000644 pw, options.proxy_command);
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000645
Damien Miller5428f641999-11-25 11:54:57 +1100646 /*
647 * If we successfully made the connection, load the host private key
648 * in case we will need it later for combined rsa-rhosts
649 * authentication. This must be done before releasing extra
650 * privileges, because the file is only readable by root.
651 */
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000652 sensitive_data.nkeys = 0;
653 sensitive_data.keys = NULL;
654 if (ok && (options.rhosts_rsa_authentication ||
655 options.hostbased_authentication)) {
656 sensitive_data.nkeys = 3;
657 sensitive_data.keys = xmalloc(sensitive_data.nkeys*sizeof(Key));
658 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
Ben Lindstromd0fca422001-03-26 13:44:06 +0000659 _PATH_HOST_KEY_FILE, "", NULL);
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000660 sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
661 _PATH_HOST_DSA_KEY_FILE, "", NULL);
662 sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
663 _PATH_HOST_RSA_KEY_FILE, "", NULL);
Damien Miller95def091999-11-25 00:26:21 +1100664 }
Damien Miller5428f641999-11-25 11:54:57 +1100665 /*
666 * Get rid of any extra privileges that we may have. We will no
667 * longer need them. Also, extra privileges could make it very hard
668 * to read identity files and other non-world-readable files from the
669 * user's home directory if it happens to be on a NFS volume where
670 * root is mapped to nobody.
671 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000672
Damien Miller5428f641999-11-25 11:54:57 +1100673 /*
674 * Note that some legacy systems need to postpone the following call
675 * to permanently_set_uid() until the private hostkey is destroyed
676 * with RSA_free(). Otherwise the calling user could ptrace() the
677 * process, read the private hostkey and impersonate the host.
678 * OpenBSD does not allow ptracing of setuid processes.
679 */
Ben Lindstrom3fcf1a22001-04-08 18:26:59 +0000680 permanently_set_uid(pw);
Damien Miller95def091999-11-25 00:26:21 +1100681
Damien Miller5428f641999-11-25 11:54:57 +1100682 /*
683 * Now that we are back to our own permissions, create ~/.ssh
684 * directory if it doesn\'t already exist.
685 */
Ben Lindstrom226cfa02001-01-22 05:34:40 +0000686 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, _PATH_SSH_USER_DIR);
Damien Miller95def091999-11-25 00:26:21 +1100687 if (stat(buf, &st) < 0)
Damien Millerbe484b52000-07-15 14:14:16 +1000688 if (mkdir(buf, 0700) < 0)
Damien Miller95def091999-11-25 00:26:21 +1100689 error("Could not create directory '%.200s'.", buf);
690
691 /* Check if the connection failed, and try "rsh" if appropriate. */
692 if (!ok) {
693 if (options.port != 0)
Damien Milleraae6c611999-12-06 11:47:28 +1100694 log("Secure connection to %.100s on port %hu refused%.100s.",
Damien Miller95def091999-11-25 00:26:21 +1100695 host, options.port,
696 options.fallback_to_rsh ? "; reverting to insecure method" : "");
697 else
698 log("Secure connection to %.100s refused%.100s.", host,
699 options.fallback_to_rsh ? "; reverting to insecure method" : "");
700
701 if (options.fallback_to_rsh) {
702 rsh_connect(host, options.user, &command);
703 fatal("rsh_connect returned");
704 }
705 exit(1);
706 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000707 /* load options.identity_files */
708 load_public_identity_files();
709
710 /* Expand ~ in known host file names. */
711 /* XXX mem-leaks: */
Damien Miller0bc1bd82000-11-13 22:57:25 +1100712 options.system_hostfile =
713 tilde_expand_filename(options.system_hostfile, original_real_uid);
714 options.user_hostfile =
715 tilde_expand_filename(options.user_hostfile, original_real_uid);
716 options.system_hostfile2 =
717 tilde_expand_filename(options.system_hostfile2, original_real_uid);
718 options.user_hostfile2 =
719 tilde_expand_filename(options.user_hostfile2, original_real_uid);
Damien Miller95def091999-11-25 00:26:21 +1100720
721 /* Log into the remote system. This never returns if the login fails. */
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000722 ssh_login(sensitive_data.keys, sensitive_data.nkeys,
723 host, (struct sockaddr *)&hostaddr, pw);
Damien Miller95def091999-11-25 00:26:21 +1100724
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000725 /* We no longer need the private host keys. Clear them now. */
726 if (sensitive_data.nkeys != 0) {
727 for (i = 0; i < sensitive_data.nkeys; i++) {
728 if (sensitive_data.keys[i] != NULL) {
729 /* Destroys contents safely */
730 debug3("clear hostkey %d", i);
731 key_free(sensitive_data.keys[i]);
732 sensitive_data.keys[i] = NULL;
733 }
734 }
735 xfree(sensitive_data.keys);
736 }
Damien Miller95def091999-11-25 00:26:21 +1100737
Damien Miller1383bd82000-04-06 12:32:37 +1000738 exit_status = compat20 ? ssh_session2() : ssh_session();
739 packet_close();
740 return exit_status;
741}
742
Damien Millerbd483e72000-04-30 10:00:53 +1000743void
744x11_get_proto(char *proto, int proto_len, char *data, int data_len)
745{
746 char line[512];
747 FILE *f;
748 int got_data = 0, i;
749
Damien Millerd3a18572000-06-07 19:55:44 +1000750 if (options.xauth_location) {
751 /* Try to get Xauthority information for the display. */
Ben Lindstrom31ca54a2001-02-09 02:11:24 +0000752 snprintf(line, sizeof line, "%.100s list %.200s 2>" _PATH_DEVNULL,
Damien Millerd3a18572000-06-07 19:55:44 +1000753 options.xauth_location, getenv("DISPLAY"));
754 f = popen(line, "r");
755 if (f && fgets(line, sizeof(line), f) &&
756 sscanf(line, "%*s %s %s", proto, data) == 2)
757 got_data = 1;
758 if (f)
759 pclose(f);
760 }
Damien Millerbd483e72000-04-30 10:00:53 +1000761 /*
762 * If we didn't get authentication data, just make up some
763 * data. The forwarding code will check the validity of the
764 * response anyway, and substitute this data. The X11
765 * server, however, will ignore this fake data and use
766 * whatever authentication mechanisms it was using otherwise
767 * for the local connection.
768 */
769 if (!got_data) {
770 u_int32_t rand = 0;
771
772 strlcpy(proto, "MIT-MAGIC-COOKIE-1", proto_len);
773 for (i = 0; i < 16; i++) {
774 if (i % 4 == 0)
775 rand = arc4random();
776 snprintf(data + 2 * i, data_len - 2 * i, "%02x", rand & 0xff);
777 rand >>= 8;
778 }
779 }
780}
781
Damien Miller0bc1bd82000-11-13 22:57:25 +1100782void
783ssh_init_forwarding(void)
784{
Kevin Steves12057502001-02-05 14:54:34 +0000785 int success = 0;
Damien Miller0bc1bd82000-11-13 22:57:25 +1100786 int i;
Kevin Steves12057502001-02-05 14:54:34 +0000787
Damien Miller0bc1bd82000-11-13 22:57:25 +1100788 /* Initiate local TCP/IP port forwardings. */
789 for (i = 0; i < options.num_local_forwards; i++) {
790 debug("Connections to local port %d forwarded to remote address %.200s:%d",
791 options.local_forwards[i].port,
792 options.local_forwards[i].host,
793 options.local_forwards[i].host_port);
Kevin Steves12057502001-02-05 14:54:34 +0000794 success += channel_request_local_forwarding(
Damien Miller0bc1bd82000-11-13 22:57:25 +1100795 options.local_forwards[i].port,
796 options.local_forwards[i].host,
797 options.local_forwards[i].host_port,
798 options.gateway_ports);
799 }
Kevin Steves12057502001-02-05 14:54:34 +0000800 if (i > 0 && success == 0)
801 error("Could not request local forwarding.");
Damien Miller0bc1bd82000-11-13 22:57:25 +1100802
803 /* Initiate remote TCP/IP port forwardings. */
804 for (i = 0; i < options.num_remote_forwards; i++) {
805 debug("Connections to remote port %d forwarded to local address %.200s:%d",
806 options.remote_forwards[i].port,
807 options.remote_forwards[i].host,
808 options.remote_forwards[i].host_port);
809 channel_request_remote_forwarding(
810 options.remote_forwards[i].port,
811 options.remote_forwards[i].host,
812 options.remote_forwards[i].host_port);
813 }
814}
815
816void
817check_agent_present(void)
818{
819 if (options.forward_agent) {
820 /* Clear agent forwarding if we don\'t have an agent. */
821 int authfd = ssh_get_authentication_socket();
822 if (authfd < 0)
823 options.forward_agent = 0;
824 else
825 ssh_close_authentication_socket(authfd);
826 }
827}
828
Damien Miller1383bd82000-04-06 12:32:37 +1000829int
830ssh_session(void)
831{
832 int type;
Damien Miller1383bd82000-04-06 12:32:37 +1000833 int plen;
834 int interactive = 0;
835 int have_tty = 0;
836 struct winsize ws;
Damien Miller1383bd82000-04-06 12:32:37 +1000837 char *cp;
838
Damien Miller95def091999-11-25 00:26:21 +1100839 /* Enable compression if requested. */
840 if (options.compression) {
841 debug("Requesting compression at level %d.", options.compression_level);
842
843 if (options.compression_level < 1 || options.compression_level > 9)
844 fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
845
846 /* Send the request. */
847 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
848 packet_put_int(options.compression_level);
849 packet_send();
850 packet_write_wait();
851 type = packet_read(&plen);
852 if (type == SSH_SMSG_SUCCESS)
853 packet_start_compression(options.compression_level);
854 else if (type == SSH_SMSG_FAILURE)
855 log("Warning: Remote host refused compression.");
856 else
857 packet_disconnect("Protocol error waiting for compression response.");
858 }
859 /* Allocate a pseudo tty if appropriate. */
860 if (tty_flag) {
861 debug("Requesting pty.");
862
863 /* Start the packet. */
864 packet_start(SSH_CMSG_REQUEST_PTY);
865
866 /* Store TERM in the packet. There is no limit on the
867 length of the string. */
868 cp = getenv("TERM");
869 if (!cp)
870 cp = "";
871 packet_put_string(cp, strlen(cp));
872
873 /* Store window size in the packet. */
874 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
875 memset(&ws, 0, sizeof(ws));
876 packet_put_int(ws.ws_row);
877 packet_put_int(ws.ws_col);
878 packet_put_int(ws.ws_xpixel);
879 packet_put_int(ws.ws_ypixel);
880
881 /* Store tty modes in the packet. */
882 tty_make_modes(fileno(stdin));
883
884 /* Send the packet, and wait for it to leave. */
885 packet_send();
886 packet_write_wait();
887
888 /* Read response from the server. */
889 type = packet_read(&plen);
Damien Miller450a7a12000-03-26 13:04:51 +1000890 if (type == SSH_SMSG_SUCCESS) {
Damien Miller95def091999-11-25 00:26:21 +1100891 interactive = 1;
Damien Miller1383bd82000-04-06 12:32:37 +1000892 have_tty = 1;
Damien Miller450a7a12000-03-26 13:04:51 +1000893 } else if (type == SSH_SMSG_FAILURE)
Damien Miller95def091999-11-25 00:26:21 +1100894 log("Warning: Remote host failed or refused to allocate a pseudo tty.");
895 else
896 packet_disconnect("Protocol error waiting for pty request response.");
897 }
898 /* Request X11 forwarding if enabled and DISPLAY is set. */
899 if (options.forward_x11 && getenv("DISPLAY") != NULL) {
Damien Millerbd483e72000-04-30 10:00:53 +1000900 char proto[512], data[512];
901 /* Get reasonable local authentication information. */
902 x11_get_proto(proto, sizeof proto, data, sizeof data);
903 /* Request forwarding with authentication spoofing. */
Damien Miller95def091999-11-25 00:26:21 +1100904 debug("Requesting X11 forwarding with authentication spoofing.");
Damien Millerbd483e72000-04-30 10:00:53 +1000905 x11_request_forwarding_with_spoofing(0, proto, data);
Damien Miller95def091999-11-25 00:26:21 +1100906
907 /* Read response from the server. */
908 type = packet_read(&plen);
909 if (type == SSH_SMSG_SUCCESS) {
Damien Miller95def091999-11-25 00:26:21 +1100910 interactive = 1;
Damien Millerbd483e72000-04-30 10:00:53 +1000911 } else if (type == SSH_SMSG_FAILURE) {
Damien Miller95def091999-11-25 00:26:21 +1100912 log("Warning: Remote host denied X11 forwarding.");
Damien Millerbd483e72000-04-30 10:00:53 +1000913 } else {
Damien Miller95def091999-11-25 00:26:21 +1100914 packet_disconnect("Protocol error waiting for X11 forwarding");
Damien Millerbd483e72000-04-30 10:00:53 +1000915 }
Damien Miller95def091999-11-25 00:26:21 +1100916 }
917 /* Tell the packet module whether this is an interactive session. */
Ben Lindstrombf555ba2001-01-18 02:04:35 +0000918 packet_set_interactive(interactive);
Damien Miller95def091999-11-25 00:26:21 +1100919
920 /* Request authentication agent forwarding if appropriate. */
Damien Miller0bc1bd82000-11-13 22:57:25 +1100921 check_agent_present();
922
Damien Miller95def091999-11-25 00:26:21 +1100923 if (options.forward_agent) {
924 debug("Requesting authentication agent forwarding.");
925 auth_request_forwarding();
926
927 /* Read response from the server. */
928 type = packet_read(&plen);
929 packet_integrity_check(plen, 0, type);
930 if (type != SSH_SMSG_SUCCESS)
931 log("Warning: Remote host denied authentication agent forwarding.");
932 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000933
Damien Miller0bc1bd82000-11-13 22:57:25 +1100934 /* Initiate port forwardings. */
935 ssh_init_forwarding();
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000936
Damien Miller5428f641999-11-25 11:54:57 +1100937 /* If requested, let ssh continue in the background. */
Damien Miller4af51302000-04-16 11:18:38 +1000938 if (fork_after_authentication_flag)
Damien Miller5428f641999-11-25 11:54:57 +1100939 if (daemon(1, 1) < 0)
940 fatal("daemon() failed: %.200s", strerror(errno));
941
942 /*
943 * If a command was specified on the command line, execute the
944 * command now. Otherwise request the server to start a shell.
945 */
Damien Miller95def091999-11-25 00:26:21 +1100946 if (buffer_len(&command) > 0) {
947 int len = buffer_len(&command);
948 if (len > 900)
949 len = 900;
950 debug("Sending command: %.*s", len, buffer_ptr(&command));
951 packet_start(SSH_CMSG_EXEC_CMD);
952 packet_put_string(buffer_ptr(&command), buffer_len(&command));
953 packet_send();
954 packet_write_wait();
955 } else {
956 debug("Requesting shell.");
957 packet_start(SSH_CMSG_EXEC_SHELL);
958 packet_send();
959 packet_write_wait();
960 }
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000961
Damien Miller95def091999-11-25 00:26:21 +1100962 /* Enter the interactive session. */
Damien Millerad833b32000-08-23 10:46:23 +1000963 return client_loop(have_tty, tty_flag ? options.escape_char : -1, 0);
Damien Miller1383bd82000-04-06 12:32:37 +1000964}
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000965
Damien Miller1383bd82000-04-06 12:32:37 +1000966void
Ben Lindstrom1e7d3062001-02-09 02:36:43 +0000967client_subsystem_reply(int type, int plen, void *ctxt)
968{
969 int id, len;
970
971 id = packet_get_int();
972 len = buffer_len(&command);
Ben Lindstrom4040fe12001-03-05 06:52:57 +0000973 if (len > 900)
974 len = 900;
Ben Lindstrom1e7d3062001-02-09 02:36:43 +0000975 packet_done();
976 if (type == SSH2_MSG_CHANNEL_FAILURE)
977 fatal("Request for subsystem '%.*s' failed on channel %d",
978 len, buffer_ptr(&command), id);
979}
980
981void
Damien Miller0bc1bd82000-11-13 22:57:25 +1100982ssh_session2_callback(int id, void *arg)
Damien Miller1383bd82000-04-06 12:32:37 +1000983{
984 int len;
Ben Lindstrombf555ba2001-01-18 02:04:35 +0000985 int interactive = 0;
986
Kevin Stevesadf74cd2001-02-05 14:22:50 +0000987 debug("client_init id %d arg %ld", id, (long)arg);
Damien Miller1383bd82000-04-06 12:32:37 +1000988
Damien Miller1383bd82000-04-06 12:32:37 +1000989 if (tty_flag) {
990 struct winsize ws;
991 char *cp;
992 cp = getenv("TERM");
993 if (!cp)
994 cp = "";
995 /* Store window size in the packet. */
996 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
997 memset(&ws, 0, sizeof(ws));
998
999 channel_request_start(id, "pty-req", 0);
1000 packet_put_cstring(cp);
1001 packet_put_int(ws.ws_col);
1002 packet_put_int(ws.ws_row);
1003 packet_put_int(ws.ws_xpixel);
1004 packet_put_int(ws.ws_ypixel);
1005 packet_put_cstring(""); /* XXX: encode terminal modes */
1006 packet_send();
Ben Lindstrombf555ba2001-01-18 02:04:35 +00001007 interactive = 1;
Damien Miller1383bd82000-04-06 12:32:37 +10001008 /* XXX wait for reply */
1009 }
Damien Millerbd483e72000-04-30 10:00:53 +10001010 if (options.forward_x11 &&
1011 getenv("DISPLAY") != NULL) {
1012 char proto[512], data[512];
1013 /* Get reasonable local authentication information. */
1014 x11_get_proto(proto, sizeof proto, data, sizeof data);
1015 /* Request forwarding with authentication spoofing. */
1016 debug("Requesting X11 forwarding with authentication spoofing.");
1017 x11_request_forwarding_with_spoofing(id, proto, data);
Ben Lindstrombf555ba2001-01-18 02:04:35 +00001018 interactive = 1;
Damien Millerbd483e72000-04-30 10:00:53 +10001019 /* XXX wait for reply */
1020 }
1021
Damien Miller0bc1bd82000-11-13 22:57:25 +11001022 check_agent_present();
1023 if (options.forward_agent) {
1024 debug("Requesting authentication agent forwarding.");
1025 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1026 packet_send();
1027 }
1028
Damien Miller1383bd82000-04-06 12:32:37 +10001029 len = buffer_len(&command);
1030 if (len > 0) {
1031 if (len > 900)
1032 len = 900;
Damien Miller832562e2001-01-30 09:30:01 +11001033 if (subsystem_flag) {
1034 debug("Sending subsystem: %.*s", len, buffer_ptr(&command));
Ben Lindstrom1e7d3062001-02-09 02:36:43 +00001035 channel_request_start(id, "subsystem", /*want reply*/ 1);
1036 /* register callback for reply */
1037 /* XXX we asume that client_loop has already been called */
1038 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &client_subsystem_reply);
1039 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &client_subsystem_reply);
Damien Miller832562e2001-01-30 09:30:01 +11001040 } else {
1041 debug("Sending command: %.*s", len, buffer_ptr(&command));
1042 channel_request_start(id, "exec", 0);
1043 }
Ben Lindstrom4040fe12001-03-05 06:52:57 +00001044 packet_put_string(buffer_ptr(&command), buffer_len(&command));
Damien Miller1383bd82000-04-06 12:32:37 +10001045 packet_send();
1046 } else {
1047 channel_request(id, "shell", 0);
1048 }
1049 /* channel_callback(id, SSH2_MSG_OPEN_CONFIGMATION, client_init, 0); */
Ben Lindstrom1e7d3062001-02-09 02:36:43 +00001050
Damien Miller1383bd82000-04-06 12:32:37 +10001051 /* register different callback, etc. XXX */
Ben Lindstrombf555ba2001-01-18 02:04:35 +00001052 packet_set_interactive(interactive);
Damien Miller1383bd82000-04-06 12:32:37 +10001053}
1054
1055int
Ben Lindstrom4c3f77d2001-04-05 23:37:36 +00001056ssh_session2_command(void)
Damien Miller1383bd82000-04-06 12:32:37 +10001057{
Ben Lindstrom4c3f77d2001-04-05 23:37:36 +00001058 int id, window, packetmax;
Damien Millerad833b32000-08-23 10:46:23 +10001059 int in, out, err;
1060
Damien Millercaf6dd62000-08-29 11:33:50 +11001061 if (stdin_null_flag) {
Ben Lindstrom31ca54a2001-02-09 02:11:24 +00001062 in = open(_PATH_DEVNULL, O_RDONLY);
Damien Millercaf6dd62000-08-29 11:33:50 +11001063 } else {
1064 in = dup(STDIN_FILENO);
1065 }
1066 out = dup(STDOUT_FILENO);
1067 err = dup(STDERR_FILENO);
1068
1069 if (in < 0 || out < 0 || err < 0)
1070 fatal("dup() in/out/err failed");
1071
Damien Miller69b69aa2000-10-28 14:19:58 +11001072 /* enable nonblocking unless tty */
1073 if (!isatty(in))
1074 set_nonblock(in);
1075 if (!isatty(out))
1076 set_nonblock(out);
1077 if (!isatty(err))
1078 set_nonblock(err);
1079
Damien Millere4340be2000-09-16 13:29:08 +11001080 window = CHAN_SES_WINDOW_DEFAULT;
1081 packetmax = CHAN_SES_PACKET_DEFAULT;
1082 if (!tty_flag) {
Damien Miller1383bd82000-04-06 12:32:37 +10001083 window *= 2;
Damien Millere4340be2000-09-16 13:29:08 +11001084 packetmax *=2;
Damien Miller1383bd82000-04-06 12:32:37 +10001085 }
Damien Miller1383bd82000-04-06 12:32:37 +10001086 id = channel_new(
1087 "session", SSH_CHANNEL_OPENING, in, out, err,
Damien Millere4340be2000-09-16 13:29:08 +11001088 window, packetmax, CHAN_EXTENDED_WRITE,
Damien Miller69b69aa2000-10-28 14:19:58 +11001089 xstrdup("client-session"), /*nonblock*/0);
Damien Miller1383bd82000-04-06 12:32:37 +10001090
Ben Lindstrom4c3f77d2001-04-05 23:37:36 +00001091debug("channel_new: %d", id);
1092
Damien Miller1383bd82000-04-06 12:32:37 +10001093 channel_open(id);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001094 channel_register_callback(id, SSH2_MSG_CHANNEL_OPEN_CONFIRMATION,
1095 ssh_session2_callback, (void *)0);
Damien Miller1383bd82000-04-06 12:32:37 +10001096
Ben Lindstrom4c3f77d2001-04-05 23:37:36 +00001097 return id;
1098}
1099
1100int
1101ssh_session2(void)
1102{
1103 int id;
1104
1105 /* XXX should be pre-session */
1106 ssh_init_forwarding();
1107
1108 id = no_shell_flag ? -1 : ssh_session2_command();
1109
1110 /* If requested, let ssh continue in the background. */
1111 if (fork_after_authentication_flag)
1112 if (daemon(1, 1) < 0)
1113 fatal("daemon() failed: %.200s", strerror(errno));
1114
Damien Millerad833b32000-08-23 10:46:23 +10001115 return client_loop(tty_flag, tty_flag ? options.escape_char : -1, id);
Damien Millerd4a8b7e1999-10-27 13:42:43 +10001116}
Damien Miller0bc1bd82000-11-13 22:57:25 +11001117
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001118void
1119load_public_identity_files(void)
1120{
1121 char *filename;
1122 Key *public;
1123 int i;
1124
1125 for (i = 0; i < options.num_identity_files; i++) {
1126 filename = tilde_expand_filename(options.identity_files[i],
1127 original_real_uid);
Ben Lindstromd0fca422001-03-26 13:44:06 +00001128 public = key_load_public(filename, NULL);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001129 debug("identity file %s type %d", filename,
1130 public ? public->type : -1);
1131 xfree(options.identity_files[i]);
1132 options.identity_files[i] = filename;
1133 options.identity_keys[i] = public;
1134 }
1135}