Annotation of src/usr.bin/ssh/ssh.c, Revision 1.352
1.352 ! djm 1: /* $OpenBSD: ssh.c,v 1.351 2010/09/02 16:08:39 markus Exp $ */
1.1 deraadt 2: /*
1.32 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
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.
9: *
1.64 deraadt 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".
15: *
16: * Copyright (c) 1999 Niels Provos. All rights reserved.
1.202 markus 17: * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
1.64 deraadt 18: *
19: * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20: * in Canada (German citizen).
21: *
22: * Redistribution and use in source and binary forms, with or without
23: * modification, are permitted provided that the following conditions
24: * are met:
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.
30: *
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.
1.32 deraadt 41: */
1.1 deraadt 42:
1.293 deraadt 43: #include <sys/types.h>
1.312 djm 44: #include <sys/ioctl.h>
1.326 dtucker 45: #include <sys/param.h>
1.312 djm 46: #include <sys/queue.h>
1.259 stevesk 47: #include <sys/resource.h>
1.280 stevesk 48: #include <sys/socket.h>
1.264 stevesk 49: #include <sys/stat.h>
1.312 djm 50: #include <sys/types.h>
51: #include <sys/time.h>
1.352 ! djm 52: #include <sys/wait.h>
1.258 stevesk 53:
1.265 stevesk 54: #include <ctype.h>
1.285 stevesk 55: #include <errno.h>
1.281 stevesk 56: #include <fcntl.h>
1.286 stevesk 57: #include <netdb.h>
1.258 stevesk 58: #include <paths.h>
1.279 stevesk 59: #include <pwd.h>
1.263 stevesk 60: #include <signal.h>
1.287 stevesk 61: #include <stddef.h>
1.291 stevesk 62: #include <stdio.h>
1.290 stevesk 63: #include <stdlib.h>
1.289 stevesk 64: #include <string.h>
1.288 stevesk 65: #include <unistd.h>
1.49 markus 66:
67: #include <openssl/evp.h>
1.72 markus 68: #include <openssl/err.h>
1.1 deraadt 69:
1.293 deraadt 70: #include "xmalloc.h"
1.84 markus 71: #include "ssh.h"
72: #include "ssh1.h"
73: #include "ssh2.h"
1.341 djm 74: #include "canohost.h"
1.84 markus 75: #include "compat.h"
76: #include "cipher.h"
1.1 deraadt 77: #include "packet.h"
78: #include "buffer.h"
1.123 markus 79: #include "channels.h"
1.49 markus 80: #include "key.h"
1.58 markus 81: #include "authfd.h"
1.49 markus 82: #include "authfile.h"
1.83 markus 83: #include "pathnames.h"
1.214 djm 84: #include "dispatch.h"
1.81 markus 85: #include "clientloop.h"
1.84 markus 86: #include "log.h"
87: #include "readconf.h"
88: #include "sshconnect.h"
89: #include "misc.h"
1.95 markus 90: #include "kex.h"
91: #include "mac.h"
1.213 deraadt 92: #include "sshpty.h"
1.212 djm 93: #include "match.h"
1.214 djm 94: #include "msg.h"
1.225 dtucker 95: #include "uidswap.h"
1.327 andreas 96: #include "roaming.h"
1.278 stevesk 97: #include "version.h"
1.49 markus 98:
1.333 markus 99: #ifdef ENABLE_PKCS11
100: #include "ssh-pkcs11.h"
1.137 jakob 101: #endif
1.127 markus 102:
1.49 markus 103: extern char *__progname;
1.1 deraadt 104:
1.316 djm 105: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 106: int debug_flag = 0;
107:
1.46 markus 108: /* Flag indicating whether a tty should be allocated */
1.1 deraadt 109: int tty_flag = 0;
1.79 markus 110: int no_tty_flag = 0;
111: int force_tty_flag = 0;
1.1 deraadt 112:
1.45 markus 113: /* don't exec a shell */
114: int no_shell_flag = 0;
115:
1.33 markus 116: /*
117: * Flag indicating that nothing should be read from stdin. This can be set
118: * on the command line.
119: */
1.1 deraadt 120: int stdin_null_flag = 0;
121:
1.33 markus 122: /*
1.344 djm 123: * Flag indicating that the current process should be backgrounded and
124: * a new slave launched in the foreground for ControlPersist.
125: */
126: int need_controlpersist_detach = 0;
127:
128: /* Copies of flags for ControlPersist foreground slave */
129: int ostdin_null_flag, ono_shell_flag, ono_tty_flag, otty_flag;
130:
131: /*
1.33 markus 132: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 133: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 134: * background.
135: */
1.1 deraadt 136: int fork_after_authentication_flag = 0;
137:
1.331 dtucker 138: /* forward stdio to remote host and port */
139: char *stdio_forward_host = NULL;
140: int stdio_forward_port = 0;
141:
1.33 markus 142: /*
143: * General data structure for command line options and options configurable
144: * in configuration files. See readconf.h.
145: */
1.1 deraadt 146: Options options;
147:
1.139 markus 148: /* optional user configfile */
149: char *config = NULL;
150:
1.33 markus 151: /*
152: * Name of the host we are connecting to. This is the name given on the
153: * command line, or the HostName specified for the user-supplied name in a
154: * configuration file.
155: */
1.1 deraadt 156: char *host;
157:
1.22 provos 158: /* socket address the host resolves to */
1.37 markus 159: struct sockaddr_storage hostaddr;
1.1 deraadt 160:
1.112 markus 161: /* Private host keys. */
1.173 markus 162: Sensitive sensitive_data;
1.1 deraadt 163:
1.10 dugsong 164: /* Original real UID. */
165: uid_t original_real_uid;
1.177 markus 166: uid_t original_effective_uid;
1.1 deraadt 167:
1.45 markus 168: /* command to be executed */
169: Buffer command;
170:
1.85 djm 171: /* Should we execute a command or invoke a subsystem? */
172: int subsystem_flag = 0;
173:
1.170 markus 174: /* # of replies received for global requests */
1.315 djm 175: static int remote_forward_confirms_received = 0;
1.170 markus 176:
1.186 djm 177: /* pid of proxycommand child process */
178: pid_t proxy_command_pid = 0;
1.313 djm 179:
180: /* mux.c */
181: extern int muxserver_sock;
182: extern u_int muxclient_command;
183:
1.186 djm 184:
1.1 deraadt 185: /* Prints a help message to the user. This function never returns. */
186:
1.126 itojun 187: static void
1.93 itojun 188: usage(void)
1.1 deraadt 189: {
1.208 markus 190: fprintf(stderr,
1.321 jmc 191: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.251 jmc 192: " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
1.334 jmc 193: " [-I pkcs11] [-i identity_file]\n"
194: " [-L [bind_address:]port:host:hostport]\n"
1.232 djm 195: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 196: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.331 dtucker 197: " [-W host:port] [-w local_tun[:remote_tun]]\n"
198: " [user@]hostname [command]\n"
1.208 markus 199: );
1.257 dtucker 200: exit(255);
1.1 deraadt 201: }
202:
1.126 itojun 203: static int ssh_session(void);
204: static int ssh_session2(void);
205: static void load_public_identity_files(void);
1.352 ! djm 206: static void main_sigchld_handler(int);
1.312 djm 207:
208: /* from muxclient.c */
209: void muxclient(const char *);
210: void muxserver_listen(void);
1.45 markus 211:
1.32 deraadt 212: /*
213: * Main program for the ssh client.
214: */
1.2 provos 215: int
216: main(int ac, char **av)
1.1 deraadt 217: {
1.326 dtucker 218: int i, r, opt, exit_status, use_syslog;
219: char *p, *cp, *line, *argv0, buf[MAXPATHLEN];
1.31 markus 220: struct stat st;
1.98 markus 221: struct passwd *pw;
1.303 djm 222: int dummy, timeout_ms;
1.144 stevesk 223: extern int optind, optreset;
224: extern char *optarg;
1.244 djm 225: struct servent *sp;
1.232 djm 226: Forward fwd;
1.250 djm 227:
228: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
229: sanitise_stdfd();
1.31 markus 230:
1.33 markus 231: /*
1.346 djm 232: * Discard other fds that are hanging around. These can cause problem
233: * with backgrounded ssh processes started by ControlPersist.
234: */
235: closefrom(STDERR_FILENO + 1);
236:
237: /*
1.33 markus 238: * Save the original real uid. It will be needed later (uid-swapping
239: * may clobber the real uid).
240: */
1.31 markus 241: original_real_uid = getuid();
242: original_effective_uid = geteuid();
243:
1.184 stevesk 244: /*
245: * Use uid-swapping to give up root privileges for the duration of
246: * option processing. We will re-instantiate the rights when we are
247: * ready to create the privileged port, and will permanently drop
248: * them when the port has been created (actually, when the connection
249: * has been made, as we may need to create the port several times).
250: */
251: PRIV_END;
252:
1.31 markus 253: /* If we are installed setuid root be careful to not drop core. */
254: if (original_real_uid != original_effective_uid) {
255: struct rlimit rlim;
256: rlim.rlim_cur = rlim.rlim_max = 0;
257: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
258: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 259: }
1.107 markus 260: /* Get user data. */
261: pw = getpwuid(original_real_uid);
262: if (!pw) {
1.191 itojun 263: logit("You don't exist, go away!");
1.257 dtucker 264: exit(255);
1.107 markus 265: }
266: /* Take a copy of the returned structure. */
267: pw = pwcopy(pw);
1.31 markus 268:
1.33 markus 269: /*
270: * Set our umask to something reasonable, as some files are created
271: * with the default umask. This will make them world-readable but
272: * writable only by the owner, which is ok for all files for which we
273: * don't set the modes explicitly.
274: */
1.31 markus 275: umask(022);
276:
1.316 djm 277: /*
278: * Initialize option structure to indicate that no values have been
279: * set.
280: */
1.31 markus 281: initialize_options(&options);
282:
283: /* Parse command-line arguments. */
284: host = NULL;
1.320 djm 285: use_syslog = 0;
1.325 markus 286: argv0 = av[0];
1.31 markus 287:
1.266 djm 288: again:
1.316 djm 289: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.331 dtucker 290: "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
1.31 markus 291: switch (opt) {
1.91 jakob 292: case '1':
293: options.protocol = SSH_PROTO_1;
294: break;
1.47 markus 295: case '2':
296: options.protocol = SSH_PROTO_2;
297: break;
1.37 markus 298: case '4':
1.196 djm 299: options.address_family = AF_INET;
1.37 markus 300: break;
301: case '6':
1.196 djm 302: options.address_family = AF_INET6;
1.37 markus 303: break;
1.31 markus 304: case 'n':
305: stdin_null_flag = 1;
306: break;
307: case 'f':
308: fork_after_authentication_flag = 1;
309: stdin_null_flag = 1;
310: break;
311: case 'x':
312: options.forward_x11 = 0;
313: break;
314: case 'X':
315: options.forward_x11 = 1;
316: break;
1.320 djm 317: case 'y':
318: use_syslog = 1;
319: break;
1.202 markus 320: case 'Y':
321: options.forward_x11 = 1;
322: options.forward_x11_trusted = 1;
323: break;
1.31 markus 324: case 'g':
325: options.gateway_ports = 1;
326: break;
1.229 djm 327: case 'O':
1.332 djm 328: if (stdio_forward_host != NULL)
329: fatal("Cannot specify multiplexing "
330: "command with -W");
331: else if (muxclient_command != 0)
332: fatal("Multiplexing command already specified");
1.229 djm 333: if (strcmp(optarg, "check") == 0)
1.312 djm 334: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 335: else if (strcmp(optarg, "forward") == 0)
336: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 337: else if (strcmp(optarg, "exit") == 0)
1.312 djm 338: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.229 djm 339: else
340: fatal("Invalid multiplex command.");
341: break;
1.183 stevesk 342: case 'P': /* deprecated */
1.31 markus 343: options.use_privileged_port = 0;
344: break;
345: case 'a':
346: options.forward_agent = 0;
1.53 markus 347: break;
348: case 'A':
349: options.forward_agent = 1;
1.31 markus 350: break;
351: case 'k':
1.204 dtucker 352: options.gss_deleg_creds = 0;
1.297 djm 353: break;
354: case 'K':
355: options.gss_authentication = 1;
356: options.gss_deleg_creds = 1;
1.31 markus 357: break;
358: case 'i':
359: if (stat(optarg, &st) < 0) {
1.128 fgsch 360: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 361: "not accessible: %s.\n", optarg,
362: strerror(errno));
1.31 markus 363: break;
364: }
1.128 fgsch 365: if (options.num_identity_files >=
366: SSH_MAX_IDENTITY_FILES)
367: fatal("Too many identity files specified "
368: "(max %d)", SSH_MAX_IDENTITY_FILES);
369: options.identity_files[options.num_identity_files++] =
370: xstrdup(optarg);
1.31 markus 371: break;
1.127 markus 372: case 'I':
1.333 markus 373: #ifdef ENABLE_PKCS11
374: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 375: #else
1.333 markus 376: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 377: #endif
1.127 markus 378: break;
1.31 markus 379: case 't':
1.79 markus 380: if (tty_flag)
381: force_tty_flag = 1;
1.31 markus 382: tty_flag = 1;
383: break;
384: case 'v':
1.197 markus 385: if (debug_flag == 0) {
1.66 markus 386: debug_flag = 1;
387: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 388: } else {
389: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
390: options.log_level++;
1.66 markus 391: break;
1.197 markus 392: }
1.227 deraadt 393: /* FALLTHROUGH */
1.31 markus 394: case 'V':
1.209 markus 395: fprintf(stderr, "%s, %s\n",
396: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 397: if (opt == 'V')
398: exit(0);
399: break;
1.255 reyk 400: case 'w':
1.256 reyk 401: if (options.tun_open == -1)
402: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 403: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 404: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 405: fprintf(stderr,
406: "Bad tun device '%s'\n", optarg);
1.257 dtucker 407: exit(255);
1.255 reyk 408: }
409: break;
1.331 dtucker 410: case 'W':
1.332 djm 411: if (stdio_forward_host != NULL)
412: fatal("stdio forward already specified");
413: if (muxclient_command != 0)
414: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 415: if (parse_forward(&fwd, optarg, 1, 0)) {
416: stdio_forward_host = fwd.listen_host;
417: stdio_forward_port = fwd.listen_port;
418: xfree(fwd.connect_host);
419: } else {
420: fprintf(stderr,
421: "Bad stdio forwarding specification '%s'\n",
422: optarg);
423: exit(255);
424: }
425: no_tty_flag = 1;
426: no_shell_flag = 1;
427: options.clear_forwardings = 1;
428: options.exit_on_forward_failure = 1;
429: break;
1.31 markus 430: case 'q':
431: options.log_level = SYSLOG_LEVEL_QUIET;
432: break;
433: case 'e':
434: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 435: (u_char) optarg[1] >= 64 &&
436: (u_char) optarg[1] < 128)
1.78 markus 437: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 438: else if (strlen(optarg) == 1)
1.78 markus 439: options.escape_char = (u_char) optarg[0];
1.31 markus 440: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 441: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 442: else {
1.128 fgsch 443: fprintf(stderr, "Bad escape character '%s'.\n",
444: optarg);
1.257 dtucker 445: exit(255);
1.31 markus 446: }
447: break;
448: case 'c':
1.49 markus 449: if (ciphers_valid(optarg)) {
450: /* SSH2 only */
451: options.ciphers = xstrdup(optarg);
1.224 markus 452: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 453: } else {
454: /* SSH1 only */
1.74 markus 455: options.cipher = cipher_number(optarg);
456: if (options.cipher == -1) {
1.128 fgsch 457: fprintf(stderr,
458: "Unknown cipher type '%s'\n",
459: optarg);
1.257 dtucker 460: exit(255);
1.49 markus 461: }
1.128 fgsch 462: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 463: options.ciphers = "3des-cbc";
1.128 fgsch 464: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 465: options.ciphers = "blowfish-cbc";
1.128 fgsch 466: else
1.74 markus 467: options.ciphers = (char *)-1;
1.95 markus 468: }
469: break;
470: case 'm':
471: if (mac_valid(optarg))
472: options.macs = xstrdup(optarg);
473: else {
1.128 fgsch 474: fprintf(stderr, "Unknown mac type '%s'\n",
475: optarg);
1.257 dtucker 476: exit(255);
1.31 markus 477: }
478: break;
1.214 djm 479: case 'M':
1.242 djm 480: if (options.control_master == SSHCTL_MASTER_YES)
481: options.control_master = SSHCTL_MASTER_ASK;
482: else
483: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 484: break;
1.31 markus 485: case 'p':
1.113 stevesk 486: options.port = a2port(optarg);
1.323 djm 487: if (options.port <= 0) {
1.109 markus 488: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 489: exit(255);
1.109 markus 490: }
1.31 markus 491: break;
492: case 'l':
493: options.user = optarg;
494: break;
1.141 stevesk 495:
496: case 'L':
1.324 djm 497: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 498: add_local_forward(&options, &fwd);
499: else {
1.128 fgsch 500: fprintf(stderr,
1.232 djm 501: "Bad local forwarding specification '%s'\n",
1.128 fgsch 502: optarg);
1.257 dtucker 503: exit(255);
1.31 markus 504: }
1.232 djm 505: break;
506:
507: case 'R':
1.324 djm 508: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 509: add_remote_forward(&options, &fwd);
510: } else {
1.128 fgsch 511: fprintf(stderr,
1.232 djm 512: "Bad remote forwarding specification "
513: "'%s'\n", optarg);
1.257 dtucker 514: exit(255);
1.31 markus 515: }
516: break;
1.108 markus 517:
518: case 'D':
1.324 djm 519: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 520: add_local_forward(&options, &fwd);
1.232 djm 521: } else {
1.322 stevesk 522: fprintf(stderr,
523: "Bad dynamic forwarding specification "
524: "'%s'\n", optarg);
1.257 dtucker 525: exit(255);
1.109 markus 526: }
1.108 markus 527: break;
528:
1.31 markus 529: case 'C':
530: options.compression = 1;
531: break;
1.45 markus 532: case 'N':
533: no_shell_flag = 1;
534: no_tty_flag = 1;
535: break;
536: case 'T':
537: no_tty_flag = 1;
538: break;
1.31 markus 539: case 'o':
540: dummy = 1;
1.205 markus 541: line = xstrdup(optarg);
1.128 fgsch 542: if (process_config_line(&options, host ? host : "",
1.205 markus 543: line, "command-line", 0, &dummy) != 0)
1.257 dtucker 544: exit(255);
1.205 markus 545: xfree(line);
1.31 markus 546: break;
1.85 djm 547: case 's':
548: subsystem_flag = 1;
1.117 markus 549: break;
1.214 djm 550: case 'S':
551: if (options.control_path != NULL)
552: free(options.control_path);
553: options.control_path = xstrdup(optarg);
554: break;
1.117 markus 555: case 'b':
556: options.bind_address = optarg;
1.85 djm 557: break;
1.139 markus 558: case 'F':
559: config = optarg;
560: break;
1.31 markus 561: default:
562: usage();
1.1 deraadt 563: }
1.31 markus 564: }
565:
1.128 fgsch 566: ac -= optind;
567: av += optind;
568:
1.329 guenther 569: if (ac > 0 && !host) {
1.188 markus 570: if (strrchr(*av, '@')) {
1.128 fgsch 571: p = xstrdup(*av);
1.188 markus 572: cp = strrchr(p, '@');
1.128 fgsch 573: if (cp == NULL || cp == p)
574: usage();
575: options.user = p;
576: *cp = '\0';
577: host = ++cp;
578: } else
579: host = *av;
1.189 millert 580: if (ac > 1) {
581: optind = optreset = 1;
1.128 fgsch 582: goto again;
583: }
1.189 millert 584: ac--, av++;
1.128 fgsch 585: }
586:
1.31 markus 587: /* Check that we got a host name. */
588: if (!host)
589: usage();
590:
1.350 djm 591: OpenSSL_add_all_algorithms();
1.72 markus 592: ERR_load_crypto_strings();
1.31 markus 593:
594: /* Initialize the command to execute on remote host. */
595: buffer_init(&command);
1.1 deraadt 596:
1.33 markus 597: /*
598: * Save the command to execute on the remote host in a buffer. There
599: * is no limit on the length of the command, except by the maximum
600: * packet size. Also sets the tty flag if there is no command.
601: */
1.128 fgsch 602: if (!ac) {
1.31 markus 603: /* No command specified - execute shell on a tty. */
604: tty_flag = 1;
1.85 djm 605: if (subsystem_flag) {
1.128 fgsch 606: fprintf(stderr,
607: "You must specify a subsystem to invoke.\n");
1.85 djm 608: usage();
609: }
1.31 markus 610: } else {
1.128 fgsch 611: /* A command has been specified. Store it into the buffer. */
612: for (i = 0; i < ac; i++) {
613: if (i)
1.31 markus 614: buffer_append(&command, " ", 1);
615: buffer_append(&command, av[i], strlen(av[i]));
616: }
617: }
618:
619: /* Cannot fork to background if no command. */
1.316 djm 620: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
621: !no_shell_flag)
622: fatal("Cannot fork into background without a command "
623: "to execute.");
1.31 markus 624:
625: /* Allocate a tty by default if no command specified. */
626: if (buffer_len(&command) == 0)
627: tty_flag = 1;
628:
1.180 deraadt 629: /* Force no tty */
1.336 djm 630: if (no_tty_flag || muxclient_command != 0)
1.75 markus 631: tty_flag = 0;
1.31 markus 632: /* Do not allocate a tty if stdin is not a tty. */
1.236 djm 633: if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
1.31 markus 634: if (tty_flag)
1.316 djm 635: logit("Pseudo-terminal will not be allocated because "
636: "stdin is not a terminal.");
1.31 markus 637: tty_flag = 0;
638: }
1.45 markus 639:
1.101 markus 640: /*
641: * Initialize "log" output. Since we are the client all output
642: * actually goes to stderr.
643: */
1.325 markus 644: log_init(argv0,
1.316 djm 645: options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
1.320 djm 646: SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 647:
1.139 markus 648: /*
649: * Read per-user configuration file. Ignore the system wide config
650: * file if the user specifies a config file on the command line.
651: */
652: if (config != NULL) {
1.211 djm 653: if (!read_config_file(config, host, &options, 0))
1.142 stevesk 654: fatal("Can't open user config file %.100s: "
655: "%.100s", config, strerror(errno));
1.295 stevesk 656: } else {
1.326 dtucker 657: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
1.139 markus 658: _PATH_SSH_USER_CONFFILE);
1.326 dtucker 659: if (r > 0 && (size_t)r < sizeof(buf))
660: (void)read_config_file(buf, host, &options, 1);
1.139 markus 661:
1.145 markus 662: /* Read systemwide configuration file after use config. */
1.223 deraadt 663: (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
1.210 djm 664: &options, 0);
1.139 markus 665: }
1.31 markus 666:
667: /* Fill configuration defaults. */
668: fill_default_options(&options);
669:
1.196 djm 670: channel_set_af(options.address_family);
671:
1.31 markus 672: /* reinit */
1.325 markus 673: log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 674:
675: if (options.user == NULL)
676: options.user = xstrdup(pw->pw_name);
677:
1.317 dtucker 678: /* Get default port if port has not been set. */
679: if (options.port == 0) {
680: sp = getservbyname(SSH_SERVICE_NAME, "tcp");
681: options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
682: }
683:
1.343 djm 684: if (options.hostname != NULL) {
685: host = percent_expand(options.hostname,
686: "h", host, (char *)NULL);
687: }
688:
1.317 dtucker 689: if (options.local_command != NULL) {
690: char thishost[NI_MAXHOST];
691:
692: if (gethostname(thishost, sizeof(thishost)) == -1)
693: fatal("gethostname: %s", strerror(errno));
694: snprintf(buf, sizeof(buf), "%d", options.port);
695: debug3("expanding LocalCommand: %s", options.local_command);
696: cp = options.local_command;
697: options.local_command = percent_expand(cp, "d", pw->pw_dir,
1.343 djm 698: "h", host, "l", thishost, "n", host, "r", options.user,
699: "p", buf, "u", pw->pw_name, (char *)NULL);
1.317 dtucker 700: debug3("expanded LocalCommand: %s", options.local_command);
701: xfree(cp);
702: }
1.195 markus 703:
704: /* force lowercase for hostkey matching */
705: if (options.host_key_alias != NULL) {
706: for (p = options.host_key_alias; *p; p++)
707: if (isupper(*p))
1.271 deraadt 708: *p = (char)tolower(*p);
1.246 djm 709: }
710:
1.190 markus 711: if (options.proxy_command != NULL &&
1.304 dtucker 712: strcmp(options.proxy_command, "none") == 0) {
713: xfree(options.proxy_command);
1.190 markus 714: options.proxy_command = NULL;
1.304 dtucker 715: }
1.245 djm 716: if (options.control_path != NULL &&
1.304 dtucker 717: strcmp(options.control_path, "none") == 0) {
718: xfree(options.control_path);
1.245 djm 719: options.control_path = NULL;
1.304 dtucker 720: }
1.31 markus 721:
1.214 djm 722: if (options.control_path != NULL) {
1.275 djm 723: char thishost[NI_MAXHOST];
1.261 djm 724:
1.275 djm 725: if (gethostname(thishost, sizeof(thishost)) == -1)
1.261 djm 726: fatal("gethostname: %s", strerror(errno));
1.241 djm 727: snprintf(buf, sizeof(buf), "%d", options.port);
728: cp = tilde_expand_filename(options.control_path,
729: original_real_uid);
1.304 dtucker 730: xfree(options.control_path);
1.241 djm 731: options.control_path = percent_expand(cp, "p", buf, "h", host,
1.275 djm 732: "r", options.user, "l", thishost, (char *)NULL);
1.241 djm 733: xfree(cp);
1.214 djm 734: }
1.312 djm 735: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 736: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 737: if (options.control_path != NULL)
1.312 djm 738: muxclient(options.control_path);
1.214 djm 739:
1.303 djm 740: timeout_ms = options.connection_timeout * 1000;
741:
1.77 markus 742: /* Open a connection to the remote host. */
1.203 djm 743: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 744: options.address_family, options.connection_attempts, &timeout_ms,
745: options.tcp_keep_alive,
1.177 markus 746: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 747: options.proxy_command) != 0)
1.257 dtucker 748: exit(255);
1.31 markus 749:
1.303 djm 750: if (timeout_ms > 0)
751: debug3("timeout: %d ms remain after connect", timeout_ms);
752:
1.33 markus 753: /*
754: * If we successfully made the connection, load the host private key
755: * in case we will need it later for combined rsa-rhosts
756: * authentication. This must be done before releasing extra
757: * privileges, because the file is only readable by root.
1.174 markus 758: * If we cannot access the private keys, load the public keys
759: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 760: */
1.112 markus 761: sensitive_data.nkeys = 0;
762: sensitive_data.keys = NULL;
1.173 markus 763: sensitive_data.external_keysign = 0;
1.178 markus 764: if (options.rhosts_rsa_authentication ||
765: options.hostbased_authentication) {
1.349 djm 766: sensitive_data.nkeys = 7;
1.274 deraadt 767: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 768: sizeof(Key));
1.177 markus 769:
770: PRIV_START;
1.112 markus 771: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 772: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.345 djm 773: sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
774: _PATH_HOST_DSA_KEY_FILE, "", NULL);
1.349 djm 775: sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
776: _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
777: sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1.345 djm 778: _PATH_HOST_RSA_KEY_FILE, "", NULL);
1.349 djm 779: sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
1.276 dtucker 780: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.349 djm 781: sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
782: _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
783: sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
1.276 dtucker 784: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 785: PRIV_END;
1.173 markus 786:
1.181 markus 787: if (options.hostbased_authentication == 1 &&
788: sensitive_data.keys[0] == NULL &&
1.349 djm 789: sensitive_data.keys[4] == NULL &&
790: sensitive_data.keys[5] == NULL &&
791: sensitive_data.keys[6] == NULL) {
1.345 djm 792: sensitive_data.keys[1] = key_load_cert(
793: _PATH_HOST_DSA_KEY_FILE);
794: sensitive_data.keys[2] = key_load_cert(
1.349 djm 795: _PATH_HOST_ECDSA_KEY_FILE);
796: sensitive_data.keys[3] = key_load_cert(
1.345 djm 797: _PATH_HOST_RSA_KEY_FILE);
1.349 djm 798: sensitive_data.keys[4] = key_load_public(
1.173 markus 799: _PATH_HOST_DSA_KEY_FILE, NULL);
1.349 djm 800: sensitive_data.keys[5] = key_load_public(
801: _PATH_HOST_ECDSA_KEY_FILE, NULL);
802: sensitive_data.keys[6] = key_load_public(
1.173 markus 803: _PATH_HOST_RSA_KEY_FILE, NULL);
804: sensitive_data.external_keysign = 1;
805: }
1.31 markus 806: }
1.33 markus 807: /*
808: * Get rid of any extra privileges that we may have. We will no
809: * longer need them. Also, extra privileges could make it very hard
810: * to read identity files and other non-world-readable files from the
811: * user's home directory if it happens to be on a NFS volume where
812: * root is mapped to nobody.
813: */
1.225 dtucker 814: if (original_effective_uid == 0) {
815: PRIV_START;
816: permanently_set_uid(pw);
817: }
1.31 markus 818:
1.33 markus 819: /*
820: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 821: * directory if it doesn't already exist.
1.33 markus 822: */
1.326 dtucker 823: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1.316 djm 824: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1.326 dtucker 825: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
1.57 djm 826: if (mkdir(buf, 0700) < 0)
1.31 markus 827: error("Could not create directory '%.200s'.", buf);
828:
1.104 markus 829: /* load options.identity_files */
830: load_public_identity_files();
831:
832: /* Expand ~ in known host file names. */
833: /* XXX mem-leaks: */
1.72 markus 834: options.system_hostfile =
835: tilde_expand_filename(options.system_hostfile, original_real_uid);
836: options.user_hostfile =
837: tilde_expand_filename(options.user_hostfile, original_real_uid);
838: options.system_hostfile2 =
839: tilde_expand_filename(options.system_hostfile2, original_real_uid);
840: options.user_hostfile2 =
841: tilde_expand_filename(options.user_hostfile2, original_real_uid);
1.149 markus 842:
843: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 ! djm 844: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 845:
1.316 djm 846: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 847: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
848: pw, timeout_ms);
1.339 djm 849:
850: if (packet_connection_is_on_socket()) {
851: verbose("Authenticated to %s ([%s]:%d).", host,
852: get_remote_ipaddr(), get_remote_port());
853: } else {
854: verbose("Authenticated to %s (via proxy).", host);
855: }
1.31 markus 856:
1.112 markus 857: /* We no longer need the private host keys. Clear them now. */
858: if (sensitive_data.nkeys != 0) {
859: for (i = 0; i < sensitive_data.nkeys; i++) {
860: if (sensitive_data.keys[i] != NULL) {
861: /* Destroys contents safely */
862: debug3("clear hostkey %d", i);
863: key_free(sensitive_data.keys[i]);
864: sensitive_data.keys[i] = NULL;
865: }
866: }
867: xfree(sensitive_data.keys);
1.134 markus 868: }
869: for (i = 0; i < options.num_identity_files; i++) {
870: if (options.identity_files[i]) {
871: xfree(options.identity_files[i]);
872: options.identity_files[i] = NULL;
873: }
874: if (options.identity_keys[i]) {
875: key_free(options.identity_keys[i]);
876: options.identity_keys[i] = NULL;
877: }
1.112 markus 878: }
1.31 markus 879:
1.45 markus 880: exit_status = compat20 ? ssh_session2() : ssh_session();
881: packet_close();
1.186 djm 882:
1.312 djm 883: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 884: unlink(options.control_path);
885:
1.186 djm 886: /*
1.203 djm 887: * Send SIGHUP to proxy command if used. We don't wait() in
1.186 djm 888: * case it hangs and instead rely on init to reap the child
889: */
890: if (proxy_command_pid > 1)
891: kill(proxy_command_pid, SIGHUP);
892:
1.45 markus 893: return exit_status;
894: }
895:
1.344 djm 896: static void
897: control_persist_detach(void)
898: {
899: pid_t pid;
1.346 djm 900: int devnull;
1.344 djm 901:
902: debug("%s: backgrounding master process", __func__);
903:
904: /*
905: * master (current process) into the background, and make the
906: * foreground process a client of the backgrounded master.
907: */
908: switch ((pid = fork())) {
909: case -1:
910: fatal("%s: fork: %s", __func__, strerror(errno));
911: case 0:
912: /* Child: master process continues mainloop */
913: break;
914: default:
915: /* Parent: set up mux slave to connect to backgrounded master */
916: debug2("%s: background process is %ld", __func__, (long)pid);
917: stdin_null_flag = ostdin_null_flag;
918: no_shell_flag = ono_shell_flag;
919: no_tty_flag = ono_tty_flag;
920: tty_flag = otty_flag;
921: close(muxserver_sock);
922: muxserver_sock = -1;
1.351 markus 923: options.control_master = SSHCTL_MASTER_NO;
1.344 djm 924: muxclient(options.control_path);
925: /* muxclient() doesn't return on success. */
926: fatal("Failed to connect to new control master");
927: }
1.346 djm 928: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
929: error("%s: open(\"/dev/null\"): %s", __func__,
930: strerror(errno));
931: } else {
932: if (dup2(devnull, STDIN_FILENO) == -1 ||
933: dup2(devnull, STDOUT_FILENO) == -1)
934: error("%s: dup2: %s", __func__, strerror(errno));
935: if (devnull > STDERR_FILENO)
936: close(devnull);
937: }
1.344 djm 938: }
939:
940: /* Do fork() after authentication. Used by "ssh -f" */
941: static void
942: fork_postauth(void)
943: {
944: if (need_controlpersist_detach)
945: control_persist_detach();
946: debug("forking to background");
947: fork_after_authentication_flag = 0;
948: if (daemon(1, 1) < 0)
949: fatal("daemon() failed: %.200s", strerror(errno));
950: }
951:
1.315 djm 952: /* Callback for remote forward global requests */
953: static void
954: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
955: {
956: Forward *rfwd = (Forward *)ctxt;
957:
1.324 djm 958: /* XXX verbose() on failure? */
1.315 djm 959: debug("remote forward %s for: listen %d, connect %s:%d",
960: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
961: rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
1.324 djm 962: if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
1.338 markus 963: rfwd->allocated_port = packet_get_int();
1.324 djm 964: logit("Allocated port %u for remote forward to %s:%d",
1.338 markus 965: rfwd->allocated_port,
966: rfwd->connect_host, rfwd->connect_port);
1.324 djm 967: }
968:
1.315 djm 969: if (type == SSH2_MSG_REQUEST_FAILURE) {
970: if (options.exit_on_forward_failure)
971: fatal("Error: remote port forwarding failed for "
972: "listen port %d", rfwd->listen_port);
973: else
974: logit("Warning: remote port forwarding failed for "
975: "listen port %d", rfwd->listen_port);
976: }
1.318 djm 977: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 978: debug("All remote forwarding requests processed");
1.344 djm 979: if (fork_after_authentication_flag)
980: fork_postauth();
1.318 djm 981: }
1.315 djm 982: }
983:
1.126 itojun 984: static void
1.331 dtucker 985: client_cleanup_stdio_fwd(int id, void *arg)
986: {
987: debug("stdio forwarding: done");
988: cleanup_exit(0);
989: }
990:
991: static int
992: client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
993: {
994: Channel *c;
1.332 djm 995: int in, out;
1.331 dtucker 996:
997: debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
998: port_to_connect);
1.332 djm 999:
1000: in = dup(STDIN_FILENO);
1001: out = dup(STDOUT_FILENO);
1002: if (in < 0 || out < 0)
1003: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1004:
1005: if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
1006: in, out)) == NULL)
1.331 dtucker 1007: return 0;
1008: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1009: return 1;
1010: }
1011:
1012: static void
1.70 markus 1013: ssh_init_forwarding(void)
1014: {
1.86 markus 1015: int success = 0;
1.70 markus 1016: int i;
1.331 dtucker 1017:
1018: if (stdio_forward_host != NULL) {
1019: if (!compat20) {
1020: fatal("stdio forwarding require Protocol 2");
1021: }
1022: if (!client_setup_stdio_fwd(stdio_forward_host,
1023: stdio_forward_port))
1024: fatal("Failed to connect in stdio forward mode.");
1025: }
1.86 markus 1026:
1.70 markus 1027: /* Initiate local TCP/IP port forwardings. */
1028: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1029: debug("Local connections to %.200s:%d forwarded to remote "
1030: "address %.200s:%d",
1.234 deraadt 1031: (options.local_forwards[i].listen_host == NULL) ?
1032: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1033: options.local_forwards[i].listen_host,
1034: options.local_forwards[i].listen_port,
1035: options.local_forwards[i].connect_host,
1036: options.local_forwards[i].connect_port);
1.158 markus 1037: success += channel_setup_local_fwd_listener(
1.232 djm 1038: options.local_forwards[i].listen_host,
1039: options.local_forwards[i].listen_port,
1040: options.local_forwards[i].connect_host,
1041: options.local_forwards[i].connect_port,
1.70 markus 1042: options.gateway_ports);
1043: }
1.283 markus 1044: if (i > 0 && success != i && options.exit_on_forward_failure)
1045: fatal("Could not request local forwarding.");
1.86 markus 1046: if (i > 0 && success == 0)
1047: error("Could not request local forwarding.");
1.70 markus 1048:
1049: /* Initiate remote TCP/IP port forwardings. */
1050: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1051: debug("Remote connections from %.200s:%d forwarded to "
1052: "local address %.200s:%d",
1.248 djm 1053: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1054: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1055: options.remote_forwards[i].listen_port,
1056: options.remote_forwards[i].connect_host,
1057: options.remote_forwards[i].connect_port);
1.283 markus 1058: if (channel_request_remote_forwarding(
1.232 djm 1059: options.remote_forwards[i].listen_host,
1060: options.remote_forwards[i].listen_port,
1061: options.remote_forwards[i].connect_host,
1.283 markus 1062: options.remote_forwards[i].connect_port) < 0) {
1063: if (options.exit_on_forward_failure)
1064: fatal("Could not request remote forwarding.");
1065: else
1066: logit("Warning: Could not request remote "
1067: "forwarding.");
1068: }
1.315 djm 1069: client_register_global_confirm(ssh_confirm_remote_forward,
1070: &options.remote_forwards[i]);
1.70 markus 1071: }
1.301 djm 1072:
1073: /* Initiate tunnel forwarding. */
1074: if (options.tun_open != SSH_TUNMODE_NO) {
1075: if (client_request_tun_fwd(options.tun_open,
1076: options.tun_local, options.tun_remote) == -1) {
1077: if (options.exit_on_forward_failure)
1078: fatal("Could not request tunnel forwarding.");
1079: else
1080: error("Could not request tunnel forwarding.");
1081: }
1082: }
1.70 markus 1083: }
1084:
1.126 itojun 1085: static void
1.70 markus 1086: check_agent_present(void)
1087: {
1088: if (options.forward_agent) {
1.254 djm 1089: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 1090: if (!ssh_agent_present())
1.70 markus 1091: options.forward_agent = 0;
1092: }
1093: }
1094:
1.126 itojun 1095: static int
1.45 markus 1096: ssh_session(void)
1097: {
1098: int type;
1099: int interactive = 0;
1100: int have_tty = 0;
1101: struct winsize ws;
1102: char *cp;
1.243 djm 1103: const char *display;
1.45 markus 1104:
1.31 markus 1105: /* Enable compression if requested. */
1106: if (options.compression) {
1.316 djm 1107: debug("Requesting compression at level %d.",
1108: options.compression_level);
1.31 markus 1109:
1.316 djm 1110: if (options.compression_level < 1 ||
1111: options.compression_level > 9)
1112: fatal("Compression level must be from 1 (fast) to "
1113: "9 (slow, best).");
1.31 markus 1114:
1115: /* Send the request. */
1116: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1117: packet_put_int(options.compression_level);
1118: packet_send();
1119: packet_write_wait();
1.156 markus 1120: type = packet_read();
1.31 markus 1121: if (type == SSH_SMSG_SUCCESS)
1122: packet_start_compression(options.compression_level);
1123: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1124: logit("Warning: Remote host refused compression.");
1.31 markus 1125: else
1.316 djm 1126: packet_disconnect("Protocol error waiting for "
1127: "compression response.");
1.31 markus 1128: }
1129: /* Allocate a pseudo tty if appropriate. */
1130: if (tty_flag) {
1131: debug("Requesting pty.");
1132:
1133: /* Start the packet. */
1134: packet_start(SSH_CMSG_REQUEST_PTY);
1135:
1136: /* Store TERM in the packet. There is no limit on the
1137: length of the string. */
1138: cp = getenv("TERM");
1139: if (!cp)
1140: cp = "";
1.124 markus 1141: packet_put_cstring(cp);
1.31 markus 1142:
1143: /* Store window size in the packet. */
1144: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1145: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1146: packet_put_int((u_int)ws.ws_row);
1147: packet_put_int((u_int)ws.ws_col);
1148: packet_put_int((u_int)ws.ws_xpixel);
1149: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1150:
1151: /* Store tty modes in the packet. */
1.115 stevesk 1152: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1153:
1154: /* Send the packet, and wait for it to leave. */
1155: packet_send();
1156: packet_write_wait();
1157:
1158: /* Read response from the server. */
1.156 markus 1159: type = packet_read();
1.43 markus 1160: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1161: interactive = 1;
1.45 markus 1162: have_tty = 1;
1.43 markus 1163: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1164: logit("Warning: Remote host failed or refused to "
1165: "allocate a pseudo tty.");
1.31 markus 1166: else
1.316 djm 1167: packet_disconnect("Protocol error waiting for pty "
1168: "request response.");
1.31 markus 1169: }
1170: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1171: display = getenv("DISPLAY");
1172: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1173: char *proto, *data;
1.50 markus 1174: /* Get reasonable local authentication information. */
1.243 djm 1175: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1176: options.forward_x11_trusted,
1177: options.forward_x11_timeout,
1178: &proto, &data);
1.50 markus 1179: /* Request forwarding with authentication spoofing. */
1.316 djm 1180: debug("Requesting X11 forwarding with authentication "
1181: "spoofing.");
1.243 djm 1182: x11_request_forwarding_with_spoofing(0, display, proto, data);
1.31 markus 1183:
1184: /* Read response from the server. */
1.156 markus 1185: type = packet_read();
1.31 markus 1186: if (type == SSH_SMSG_SUCCESS) {
1187: interactive = 1;
1.50 markus 1188: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1189: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1190: } else {
1.316 djm 1191: packet_disconnect("Protocol error waiting for X11 "
1192: "forwarding");
1.50 markus 1193: }
1.31 markus 1194: }
1195: /* Tell the packet module whether this is an interactive session. */
1.80 markus 1196: packet_set_interactive(interactive);
1.31 markus 1197:
1198: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1199: check_agent_present();
1200:
1.31 markus 1201: if (options.forward_agent) {
1202: debug("Requesting authentication agent forwarding.");
1203: auth_request_forwarding();
1204:
1205: /* Read response from the server. */
1.156 markus 1206: type = packet_read();
1.155 markus 1207: packet_check_eom();
1.31 markus 1208: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1209: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1210: }
1211:
1.70 markus 1212: /* Initiate port forwardings. */
1213: ssh_init_forwarding();
1.305 dtucker 1214:
1215: /* Execute a local command */
1216: if (options.local_command != NULL &&
1217: options.permit_local_command)
1218: ssh_local_cmd(options.local_command);
1.34 markus 1219:
1.318 djm 1220: /*
1221: * If requested and we are not interested in replies to remote
1222: * forwarding requests, then let ssh continue in the background.
1223: */
1.344 djm 1224: if (fork_after_authentication_flag) {
1225: if (options.exit_on_forward_failure &&
1226: options.num_remote_forwards > 0) {
1227: debug("deferring postauth fork until remote forward "
1228: "confirmation received");
1229: } else
1230: fork_postauth();
1.318 djm 1231: }
1.31 markus 1232:
1.33 markus 1233: /*
1234: * If a command was specified on the command line, execute the
1235: * command now. Otherwise request the server to start a shell.
1236: */
1.31 markus 1237: if (buffer_len(&command) > 0) {
1238: int len = buffer_len(&command);
1239: if (len > 900)
1240: len = 900;
1.316 djm 1241: debug("Sending command: %.*s", len,
1242: (u_char *)buffer_ptr(&command));
1.31 markus 1243: packet_start(SSH_CMSG_EXEC_CMD);
1244: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1245: packet_send();
1246: packet_write_wait();
1247: } else {
1248: debug("Requesting shell.");
1249: packet_start(SSH_CMSG_EXEC_SHELL);
1250: packet_send();
1251: packet_write_wait();
1252: }
1253:
1254: /* Enter the interactive session. */
1.119 stevesk 1255: return client_loop(have_tty, tty_flag ?
1256: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1257: }
1258:
1.214 djm 1259: /* request pty/x11/agent/tcpfwd/shell for channel */
1260: static void
1.337 djm 1261: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1262: {
1.215 djm 1263: extern char **environ;
1.243 djm 1264: const char *display;
1265: int interactive = tty_flag;
1.337 djm 1266:
1267: if (!success)
1268: return; /* No need for error message, channels code sens one */
1.215 djm 1269:
1.248 djm 1270: display = getenv("DISPLAY");
1.243 djm 1271: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1272: char *proto, *data;
1.50 markus 1273: /* Get reasonable local authentication information. */
1.243 djm 1274: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1275: options.forward_x11_trusted,
1276: options.forward_x11_timeout, &proto, &data);
1.50 markus 1277: /* Request forwarding with authentication spoofing. */
1.316 djm 1278: debug("Requesting X11 forwarding with authentication "
1279: "spoofing.");
1.243 djm 1280: x11_request_forwarding_with_spoofing(id, display, proto, data);
1.80 markus 1281: interactive = 1;
1.50 markus 1282: /* XXX wait for reply */
1283: }
1284:
1.70 markus 1285: check_agent_present();
1286: if (options.forward_agent) {
1287: debug("Requesting authentication agent forwarding.");
1288: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1289: packet_send();
1.212 djm 1290: }
1291:
1.214 djm 1292: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1293: NULL, fileno(stdin), &command, environ);
1.90 markus 1294:
1.80 markus 1295: packet_set_interactive(interactive);
1.45 markus 1296: }
1297:
1.143 markus 1298: /* open new channel for a session */
1.126 itojun 1299: static int
1.143 markus 1300: ssh_session2_open(void)
1.45 markus 1301: {
1.118 markus 1302: Channel *c;
1303: int window, packetmax, in, out, err;
1.60 markus 1304:
1.62 markus 1305: if (stdin_null_flag) {
1.93 itojun 1306: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1307: } else {
1308: in = dup(STDIN_FILENO);
1309: }
1.60 markus 1310: out = dup(STDOUT_FILENO);
1311: err = dup(STDERR_FILENO);
1.45 markus 1312:
1313: if (in < 0 || out < 0 || err < 0)
1.62 markus 1314: fatal("dup() in/out/err failed");
1.45 markus 1315:
1.69 markus 1316: /* enable nonblocking unless tty */
1317: if (!isatty(in))
1318: set_nonblock(in);
1319: if (!isatty(out))
1320: set_nonblock(out);
1321: if (!isatty(err))
1322: set_nonblock(err);
1323:
1.65 markus 1324: window = CHAN_SES_WINDOW_DEFAULT;
1325: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1326: if (tty_flag) {
1327: window >>= 1;
1328: packetmax >>= 1;
1.45 markus 1329: }
1.118 markus 1330: c = channel_new(
1.45 markus 1331: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1332: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1333: "client-session", /*nonblock*/0);
1.45 markus 1334:
1.143 markus 1335: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1336:
1.122 markus 1337: channel_send_open(c->self);
1.143 markus 1338: if (!no_shell_flag)
1.310 djm 1339: channel_register_open_confirm(c->self,
1340: ssh_session2_setup, NULL);
1.106 markus 1341:
1.118 markus 1342: return c->self;
1.106 markus 1343: }
1344:
1.126 itojun 1345: static int
1.106 markus 1346: ssh_session2(void)
1347: {
1.143 markus 1348: int id = -1;
1.106 markus 1349:
1350: /* XXX should be pre-session */
1351: ssh_init_forwarding();
1352:
1.344 djm 1353: /* Start listening for multiplex clients */
1354: muxserver_listen();
1355:
1356: /*
1357: * If we are in control persist mode, then prepare to background
1358: * ourselves and have a foreground client attach as a control
1359: * slave. NB. we must save copies of the flags that we override for
1360: * the backgrounding, since we defer attachment of the slave until
1361: * after the connection is fully established (in particular,
1362: * async rfwd replies have been received for ExitOnForwardFailure).
1363: */
1364: if (options.control_persist && muxserver_sock != -1) {
1365: ostdin_null_flag = stdin_null_flag;
1366: ono_shell_flag = no_shell_flag;
1367: ono_tty_flag = no_tty_flag;
1368: otty_flag = tty_flag;
1369: stdin_null_flag = 1;
1370: no_shell_flag = 1;
1371: no_tty_flag = 1;
1372: tty_flag = 0;
1373: if (!fork_after_authentication_flag)
1374: need_controlpersist_detach = 1;
1375: fork_after_authentication_flag = 1;
1376: }
1377:
1.143 markus 1378: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1379: id = ssh_session2_open();
1.314 djm 1380:
1381: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1382: if (options.control_master == SSHCTL_MASTER_NO &&
1383: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1384: debug("Requesting no-more-sessions@openssh.com");
1385: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1386: packet_put_cstring("no-more-sessions@openssh.com");
1387: packet_put_char(0);
1388: packet_send();
1389: }
1.255 reyk 1390:
1391: /* Execute a local command */
1392: if (options.local_command != NULL &&
1393: options.permit_local_command)
1394: ssh_local_cmd(options.local_command);
1.301 djm 1395:
1.342 djm 1396: /*
1397: * If requested and we are not interested in replies to remote
1398: * forwarding requests, then let ssh continue in the background.
1399: */
1.344 djm 1400: if (fork_after_authentication_flag) {
1401: if (options.exit_on_forward_failure &&
1402: options.num_remote_forwards > 0) {
1403: debug("deferring postauth fork until remote forward "
1404: "confirmation received");
1405: } else
1406: fork_postauth();
1.318 djm 1407: }
1.327 andreas 1408:
1409: if (options.use_roaming)
1410: request_roaming();
1.31 markus 1411:
1.119 stevesk 1412: return client_loop(tty_flag, tty_flag ?
1413: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1414: }
1415:
1.126 itojun 1416: static void
1.104 markus 1417: load_public_identity_files(void)
1418: {
1.275 djm 1419: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1420: char *pwdir = NULL, *pwname = NULL;
1.167 markus 1421: int i = 0;
1.104 markus 1422: Key *public;
1.275 djm 1423: struct passwd *pw;
1.335 djm 1424: u_int n_ids;
1425: char *identity_files[SSH_MAX_IDENTITY_FILES];
1426: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.333 markus 1427: #ifdef ENABLE_PKCS11
1.167 markus 1428: Key **keys;
1.333 markus 1429: int nkeys;
1.335 djm 1430: #endif /* PKCS11 */
1.104 markus 1431:
1.335 djm 1432: n_ids = 0;
1433: bzero(identity_files, sizeof(identity_files));
1434: bzero(identity_keys, sizeof(identity_keys));
1435:
1436: #ifdef ENABLE_PKCS11
1.333 markus 1437: if (options.pkcs11_provider != NULL &&
1.167 markus 1438: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1439: (pkcs11_init(!options.batch_mode) == 0) &&
1440: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1441: &keys)) > 0) {
1442: for (i = 0; i < nkeys; i++) {
1.335 djm 1443: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1444: key_free(keys[i]);
1445: continue;
1446: }
1447: identity_keys[n_ids] = keys[i];
1448: identity_files[n_ids] =
1.333 markus 1449: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 1450: n_ids++;
1.167 markus 1451: }
1452: xfree(keys);
1.127 markus 1453: }
1.333 markus 1454: #endif /* ENABLE_PKCS11 */
1.275 djm 1455: if ((pw = getpwuid(original_real_uid)) == NULL)
1456: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 1457: pwname = xstrdup(pw->pw_name);
1458: pwdir = xstrdup(pw->pw_dir);
1.275 djm 1459: if (gethostname(thishost, sizeof(thishost)) == -1)
1460: fatal("load_public_identity_files: gethostname: %s",
1461: strerror(errno));
1.335 djm 1462: for (i = 0; i < options.num_identity_files; i++) {
1463: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1464: xfree(options.identity_files[i]);
1465: continue;
1466: }
1.275 djm 1467: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1468: original_real_uid);
1.306 deraadt 1469: filename = percent_expand(cp, "d", pwdir,
1470: "u", pwname, "l", thishost, "h", host,
1.275 djm 1471: "r", options.user, (char *)NULL);
1472: xfree(cp);
1.131 millert 1473: public = key_load_public(filename, NULL);
1474: debug("identity file %s type %d", filename,
1475: public ? public->type : -1);
1476: xfree(options.identity_files[i]);
1.335 djm 1477: identity_files[n_ids] = filename;
1478: identity_keys[n_ids] = public;
1479:
1480: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1481: continue;
1482:
1483: /* Try to add the certificate variant too */
1484: xasprintf(&cp, "%s-cert", filename);
1485: public = key_load_public(cp, NULL);
1486: debug("identity file %s type %d", cp,
1487: public ? public->type : -1);
1488: if (public == NULL) {
1489: xfree(cp);
1490: continue;
1491: }
1492: if (!key_is_cert(public)) {
1493: debug("%s: key %s type %s is not a certificate",
1494: __func__, cp, key_type(public));
1495: key_free(public);
1496: xfree(cp);
1497: continue;
1498: }
1499: identity_keys[n_ids] = public;
1500: /* point to the original path, most likely the private key */
1501: identity_files[n_ids] = xstrdup(filename);
1502: n_ids++;
1503: }
1504: options.num_identity_files = n_ids;
1505: memcpy(options.identity_files, identity_files, sizeof(identity_files));
1506: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1507:
1.306 deraadt 1508: bzero(pwname, strlen(pwname));
1.307 dtucker 1509: xfree(pwname);
1.306 deraadt 1510: bzero(pwdir, strlen(pwdir));
1.307 dtucker 1511: xfree(pwdir);
1.214 djm 1512: }
1.352 ! djm 1513:
! 1514: static void
! 1515: main_sigchld_handler(int sig)
! 1516: {
! 1517: int save_errno = errno;
! 1518: pid_t pid;
! 1519: int status;
! 1520:
! 1521: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
! 1522: (pid < 0 && errno == EINTR))
! 1523: ;
! 1524:
! 1525: signal(sig, main_sigchld_handler);
! 1526: errno = save_errno;
! 1527: }
! 1528: