Annotation of src/usr.bin/ssh/ssh.c, Revision 1.374
1.374 ! djm 1: /* $OpenBSD: ssh.c,v 1.373 2013/02/22 22:09:01 djm 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:
1.359 djm 108: /* Flag indicating whether a tty should be requested */
1.1 deraadt 109: int tty_flag = 0;
110:
1.45 markus 111: /* don't exec a shell */
112: int no_shell_flag = 0;
113:
1.33 markus 114: /*
115: * Flag indicating that nothing should be read from stdin. This can be set
116: * on the command line.
117: */
1.1 deraadt 118: int stdin_null_flag = 0;
119:
1.33 markus 120: /*
1.344 djm 121: * Flag indicating that the current process should be backgrounded and
122: * a new slave launched in the foreground for ControlPersist.
123: */
124: int need_controlpersist_detach = 0;
125:
126: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 127: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 128:
129: /*
1.33 markus 130: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 131: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 132: * background.
133: */
1.1 deraadt 134: int fork_after_authentication_flag = 0;
135:
1.331 dtucker 136: /* forward stdio to remote host and port */
137: char *stdio_forward_host = NULL;
138: int stdio_forward_port = 0;
139:
1.33 markus 140: /*
141: * General data structure for command line options and options configurable
142: * in configuration files. See readconf.h.
143: */
1.1 deraadt 144: Options options;
145:
1.139 markus 146: /* optional user configfile */
147: char *config = NULL;
148:
1.33 markus 149: /*
150: * Name of the host we are connecting to. This is the name given on the
151: * command line, or the HostName specified for the user-supplied name in a
152: * configuration file.
153: */
1.1 deraadt 154: char *host;
155:
1.22 provos 156: /* socket address the host resolves to */
1.37 markus 157: struct sockaddr_storage hostaddr;
1.1 deraadt 158:
1.112 markus 159: /* Private host keys. */
1.173 markus 160: Sensitive sensitive_data;
1.1 deraadt 161:
1.10 dugsong 162: /* Original real UID. */
163: uid_t original_real_uid;
1.177 markus 164: uid_t original_effective_uid;
1.1 deraadt 165:
1.45 markus 166: /* command to be executed */
167: Buffer command;
168:
1.85 djm 169: /* Should we execute a command or invoke a subsystem? */
170: int subsystem_flag = 0;
171:
1.170 markus 172: /* # of replies received for global requests */
1.315 djm 173: static int remote_forward_confirms_received = 0;
1.170 markus 174:
1.313 djm 175: /* mux.c */
176: extern int muxserver_sock;
177: extern u_int muxclient_command;
178:
1.186 djm 179:
1.1 deraadt 180: /* Prints a help message to the user. This function never returns. */
181:
1.126 itojun 182: static void
1.93 itojun 183: usage(void)
1.1 deraadt 184: {
1.208 markus 185: fprintf(stderr,
1.321 jmc 186: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.251 jmc 187: " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
1.334 jmc 188: " [-I pkcs11] [-i identity_file]\n"
189: " [-L [bind_address:]port:host:hostport]\n"
1.232 djm 190: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 191: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.331 dtucker 192: " [-W host:port] [-w local_tun[:remote_tun]]\n"
193: " [user@]hostname [command]\n"
1.208 markus 194: );
1.257 dtucker 195: exit(255);
1.1 deraadt 196: }
197:
1.126 itojun 198: static int ssh_session(void);
199: static int ssh_session2(void);
200: static void load_public_identity_files(void);
1.352 djm 201: static void main_sigchld_handler(int);
1.312 djm 202:
203: /* from muxclient.c */
204: void muxclient(const char *);
205: void muxserver_listen(void);
1.45 markus 206:
1.361 djm 207: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
208: static void
209: tilde_expand_paths(char **paths, u_int num_paths)
210: {
211: u_int i;
212: char *cp;
213:
214: for (i = 0; i < num_paths; i++) {
215: cp = tilde_expand_filename(paths[i], original_real_uid);
216: xfree(paths[i]);
217: paths[i] = cp;
218: }
219: }
220:
1.32 deraadt 221: /*
222: * Main program for the ssh client.
223: */
1.2 provos 224: int
225: main(int ac, char **av)
1.1 deraadt 226: {
1.326 dtucker 227: int i, r, opt, exit_status, use_syslog;
1.356 djm 228: char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg;
1.358 djm 229: char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
1.31 markus 230: struct stat st;
1.98 markus 231: struct passwd *pw;
1.303 djm 232: int dummy, timeout_ms;
1.144 stevesk 233: extern int optind, optreset;
234: extern char *optarg;
1.244 djm 235: struct servent *sp;
1.232 djm 236: Forward fwd;
1.250 djm 237:
238: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
239: sanitise_stdfd();
1.31 markus 240:
1.33 markus 241: /*
1.346 djm 242: * Discard other fds that are hanging around. These can cause problem
243: * with backgrounded ssh processes started by ControlPersist.
244: */
245: closefrom(STDERR_FILENO + 1);
246:
247: /*
1.33 markus 248: * Save the original real uid. It will be needed later (uid-swapping
249: * may clobber the real uid).
250: */
1.31 markus 251: original_real_uid = getuid();
252: original_effective_uid = geteuid();
253:
1.184 stevesk 254: /*
255: * Use uid-swapping to give up root privileges for the duration of
256: * option processing. We will re-instantiate the rights when we are
257: * ready to create the privileged port, and will permanently drop
258: * them when the port has been created (actually, when the connection
259: * has been made, as we may need to create the port several times).
260: */
261: PRIV_END;
262:
1.31 markus 263: /* If we are installed setuid root be careful to not drop core. */
264: if (original_real_uid != original_effective_uid) {
265: struct rlimit rlim;
266: rlim.rlim_cur = rlim.rlim_max = 0;
267: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
268: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 269: }
1.107 markus 270: /* Get user data. */
271: pw = getpwuid(original_real_uid);
272: if (!pw) {
1.191 itojun 273: logit("You don't exist, go away!");
1.257 dtucker 274: exit(255);
1.107 markus 275: }
276: /* Take a copy of the returned structure. */
277: pw = pwcopy(pw);
1.31 markus 278:
1.33 markus 279: /*
280: * Set our umask to something reasonable, as some files are created
281: * with the default umask. This will make them world-readable but
282: * writable only by the owner, which is ok for all files for which we
283: * don't set the modes explicitly.
284: */
1.31 markus 285: umask(022);
286:
1.316 djm 287: /*
288: * Initialize option structure to indicate that no values have been
289: * set.
290: */
1.31 markus 291: initialize_options(&options);
292:
293: /* Parse command-line arguments. */
294: host = NULL;
1.320 djm 295: use_syslog = 0;
1.325 markus 296: argv0 = av[0];
1.31 markus 297:
1.266 djm 298: again:
1.316 djm 299: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.331 dtucker 300: "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
1.31 markus 301: switch (opt) {
1.91 jakob 302: case '1':
303: options.protocol = SSH_PROTO_1;
304: break;
1.47 markus 305: case '2':
306: options.protocol = SSH_PROTO_2;
307: break;
1.37 markus 308: case '4':
1.196 djm 309: options.address_family = AF_INET;
1.37 markus 310: break;
311: case '6':
1.196 djm 312: options.address_family = AF_INET6;
1.37 markus 313: break;
1.31 markus 314: case 'n':
315: stdin_null_flag = 1;
316: break;
317: case 'f':
318: fork_after_authentication_flag = 1;
319: stdin_null_flag = 1;
320: break;
321: case 'x':
322: options.forward_x11 = 0;
323: break;
324: case 'X':
325: options.forward_x11 = 1;
326: break;
1.320 djm 327: case 'y':
328: use_syslog = 1;
329: break;
1.202 markus 330: case 'Y':
331: options.forward_x11 = 1;
332: options.forward_x11_trusted = 1;
333: break;
1.31 markus 334: case 'g':
335: options.gateway_ports = 1;
336: break;
1.229 djm 337: case 'O':
1.332 djm 338: if (stdio_forward_host != NULL)
339: fatal("Cannot specify multiplexing "
340: "command with -W");
341: else if (muxclient_command != 0)
342: fatal("Multiplexing command already specified");
1.229 djm 343: if (strcmp(optarg, "check") == 0)
1.312 djm 344: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 345: else if (strcmp(optarg, "forward") == 0)
346: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 347: else if (strcmp(optarg, "exit") == 0)
1.312 djm 348: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 349: else if (strcmp(optarg, "stop") == 0)
350: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 351: else if (strcmp(optarg, "cancel") == 0)
352: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.229 djm 353: else
354: fatal("Invalid multiplex command.");
355: break;
1.183 stevesk 356: case 'P': /* deprecated */
1.31 markus 357: options.use_privileged_port = 0;
358: break;
359: case 'a':
360: options.forward_agent = 0;
1.53 markus 361: break;
362: case 'A':
363: options.forward_agent = 1;
1.31 markus 364: break;
365: case 'k':
1.204 dtucker 366: options.gss_deleg_creds = 0;
1.297 djm 367: break;
368: case 'K':
369: options.gss_authentication = 1;
370: options.gss_deleg_creds = 1;
1.31 markus 371: break;
372: case 'i':
373: if (stat(optarg, &st) < 0) {
1.128 fgsch 374: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 375: "not accessible: %s.\n", optarg,
376: strerror(errno));
1.31 markus 377: break;
378: }
1.371 dtucker 379: add_identity_file(&options, NULL, optarg, 1);
1.31 markus 380: break;
1.127 markus 381: case 'I':
1.333 markus 382: #ifdef ENABLE_PKCS11
383: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 384: #else
1.333 markus 385: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 386: #endif
1.127 markus 387: break;
1.31 markus 388: case 't':
1.359 djm 389: if (options.request_tty == REQUEST_TTY_YES)
390: options.request_tty = REQUEST_TTY_FORCE;
391: else
392: options.request_tty = REQUEST_TTY_YES;
1.31 markus 393: break;
394: case 'v':
1.197 markus 395: if (debug_flag == 0) {
1.66 markus 396: debug_flag = 1;
397: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 398: } else {
399: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
400: options.log_level++;
1.66 markus 401: break;
1.197 markus 402: }
1.227 deraadt 403: /* FALLTHROUGH */
1.31 markus 404: case 'V':
1.209 markus 405: fprintf(stderr, "%s, %s\n",
406: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 407: if (opt == 'V')
408: exit(0);
409: break;
1.255 reyk 410: case 'w':
1.256 reyk 411: if (options.tun_open == -1)
412: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 413: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 414: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 415: fprintf(stderr,
416: "Bad tun device '%s'\n", optarg);
1.257 dtucker 417: exit(255);
1.255 reyk 418: }
419: break;
1.331 dtucker 420: case 'W':
1.332 djm 421: if (stdio_forward_host != NULL)
422: fatal("stdio forward already specified");
423: if (muxclient_command != 0)
424: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 425: if (parse_forward(&fwd, optarg, 1, 0)) {
426: stdio_forward_host = fwd.listen_host;
427: stdio_forward_port = fwd.listen_port;
428: xfree(fwd.connect_host);
429: } else {
430: fprintf(stderr,
431: "Bad stdio forwarding specification '%s'\n",
432: optarg);
433: exit(255);
434: }
1.359 djm 435: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 436: no_shell_flag = 1;
437: options.clear_forwardings = 1;
438: options.exit_on_forward_failure = 1;
439: break;
1.31 markus 440: case 'q':
441: options.log_level = SYSLOG_LEVEL_QUIET;
442: break;
443: case 'e':
444: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 445: (u_char) optarg[1] >= 64 &&
446: (u_char) optarg[1] < 128)
1.78 markus 447: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 448: else if (strlen(optarg) == 1)
1.78 markus 449: options.escape_char = (u_char) optarg[0];
1.31 markus 450: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 451: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 452: else {
1.128 fgsch 453: fprintf(stderr, "Bad escape character '%s'.\n",
454: optarg);
1.257 dtucker 455: exit(255);
1.31 markus 456: }
457: break;
458: case 'c':
1.49 markus 459: if (ciphers_valid(optarg)) {
460: /* SSH2 only */
461: options.ciphers = xstrdup(optarg);
1.224 markus 462: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 463: } else {
464: /* SSH1 only */
1.74 markus 465: options.cipher = cipher_number(optarg);
466: if (options.cipher == -1) {
1.128 fgsch 467: fprintf(stderr,
468: "Unknown cipher type '%s'\n",
469: optarg);
1.257 dtucker 470: exit(255);
1.49 markus 471: }
1.128 fgsch 472: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 473: options.ciphers = "3des-cbc";
1.128 fgsch 474: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 475: options.ciphers = "blowfish-cbc";
1.128 fgsch 476: else
1.74 markus 477: options.ciphers = (char *)-1;
1.95 markus 478: }
479: break;
480: case 'm':
481: if (mac_valid(optarg))
482: options.macs = xstrdup(optarg);
483: else {
1.128 fgsch 484: fprintf(stderr, "Unknown mac type '%s'\n",
485: optarg);
1.257 dtucker 486: exit(255);
1.31 markus 487: }
488: break;
1.214 djm 489: case 'M':
1.242 djm 490: if (options.control_master == SSHCTL_MASTER_YES)
491: options.control_master = SSHCTL_MASTER_ASK;
492: else
493: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 494: break;
1.31 markus 495: case 'p':
1.113 stevesk 496: options.port = a2port(optarg);
1.323 djm 497: if (options.port <= 0) {
1.109 markus 498: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 499: exit(255);
1.109 markus 500: }
1.31 markus 501: break;
502: case 'l':
503: options.user = optarg;
504: break;
1.141 stevesk 505:
506: case 'L':
1.324 djm 507: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 508: add_local_forward(&options, &fwd);
509: else {
1.128 fgsch 510: fprintf(stderr,
1.232 djm 511: "Bad local forwarding specification '%s'\n",
1.128 fgsch 512: optarg);
1.257 dtucker 513: exit(255);
1.31 markus 514: }
1.232 djm 515: break;
516:
517: case 'R':
1.324 djm 518: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 519: add_remote_forward(&options, &fwd);
520: } else {
1.128 fgsch 521: fprintf(stderr,
1.232 djm 522: "Bad remote forwarding specification "
523: "'%s'\n", optarg);
1.257 dtucker 524: exit(255);
1.31 markus 525: }
526: break;
1.108 markus 527:
528: case 'D':
1.324 djm 529: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 530: add_local_forward(&options, &fwd);
1.232 djm 531: } else {
1.322 stevesk 532: fprintf(stderr,
533: "Bad dynamic forwarding specification "
534: "'%s'\n", optarg);
1.257 dtucker 535: exit(255);
1.109 markus 536: }
1.108 markus 537: break;
538:
1.31 markus 539: case 'C':
540: options.compression = 1;
541: break;
1.45 markus 542: case 'N':
543: no_shell_flag = 1;
1.359 djm 544: options.request_tty = REQUEST_TTY_NO;
1.45 markus 545: break;
546: case 'T':
1.359 djm 547: options.request_tty = REQUEST_TTY_NO;
1.45 markus 548: break;
1.31 markus 549: case 'o':
550: dummy = 1;
1.205 markus 551: line = xstrdup(optarg);
1.128 fgsch 552: if (process_config_line(&options, host ? host : "",
1.372 dtucker 553: line, "command-line", 0, &dummy, SSHCONF_USERCONF)
554: != 0)
1.257 dtucker 555: exit(255);
1.205 markus 556: xfree(line);
1.31 markus 557: break;
1.85 djm 558: case 's':
559: subsystem_flag = 1;
1.117 markus 560: break;
1.214 djm 561: case 'S':
562: if (options.control_path != NULL)
563: free(options.control_path);
564: options.control_path = xstrdup(optarg);
565: break;
1.117 markus 566: case 'b':
567: options.bind_address = optarg;
1.85 djm 568: break;
1.139 markus 569: case 'F':
570: config = optarg;
571: break;
1.31 markus 572: default:
573: usage();
1.1 deraadt 574: }
1.31 markus 575: }
576:
1.128 fgsch 577: ac -= optind;
578: av += optind;
579:
1.329 guenther 580: if (ac > 0 && !host) {
1.188 markus 581: if (strrchr(*av, '@')) {
1.128 fgsch 582: p = xstrdup(*av);
1.188 markus 583: cp = strrchr(p, '@');
1.128 fgsch 584: if (cp == NULL || cp == p)
585: usage();
586: options.user = p;
587: *cp = '\0';
588: host = ++cp;
589: } else
590: host = *av;
1.189 millert 591: if (ac > 1) {
592: optind = optreset = 1;
1.128 fgsch 593: goto again;
594: }
1.189 millert 595: ac--, av++;
1.128 fgsch 596: }
597:
1.31 markus 598: /* Check that we got a host name. */
599: if (!host)
600: usage();
601:
1.350 djm 602: OpenSSL_add_all_algorithms();
1.72 markus 603: ERR_load_crypto_strings();
1.31 markus 604:
605: /* Initialize the command to execute on remote host. */
606: buffer_init(&command);
1.1 deraadt 607:
1.33 markus 608: /*
609: * Save the command to execute on the remote host in a buffer. There
610: * is no limit on the length of the command, except by the maximum
611: * packet size. Also sets the tty flag if there is no command.
612: */
1.128 fgsch 613: if (!ac) {
1.31 markus 614: /* No command specified - execute shell on a tty. */
1.85 djm 615: if (subsystem_flag) {
1.128 fgsch 616: fprintf(stderr,
617: "You must specify a subsystem to invoke.\n");
1.85 djm 618: usage();
619: }
1.31 markus 620: } else {
1.128 fgsch 621: /* A command has been specified. Store it into the buffer. */
622: for (i = 0; i < ac; i++) {
623: if (i)
1.31 markus 624: buffer_append(&command, " ", 1);
625: buffer_append(&command, av[i], strlen(av[i]));
626: }
627: }
628:
629: /* Cannot fork to background if no command. */
1.316 djm 630: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
631: !no_shell_flag)
632: fatal("Cannot fork into background without a command "
633: "to execute.");
1.31 markus 634:
1.101 markus 635: /*
636: * Initialize "log" output. Since we are the client all output
637: * actually goes to stderr.
638: */
1.325 markus 639: log_init(argv0,
1.316 djm 640: options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
1.320 djm 641: SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 642:
1.139 markus 643: /*
644: * Read per-user configuration file. Ignore the system wide config
645: * file if the user specifies a config file on the command line.
646: */
647: if (config != NULL) {
1.374 ! djm 648: if (strcasecmp(config, "none") != 0 &&
! 649: !read_config_file(config, host, &options, SSHCONF_USERCONF))
1.142 stevesk 650: fatal("Can't open user config file %.100s: "
651: "%.100s", config, strerror(errno));
1.295 stevesk 652: } else {
1.326 dtucker 653: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
1.139 markus 654: _PATH_SSH_USER_CONFFILE);
1.326 dtucker 655: if (r > 0 && (size_t)r < sizeof(buf))
1.372 dtucker 656: (void)read_config_file(buf, host, &options,
657: SSHCONF_CHECKPERM|SSHCONF_USERCONF);
1.139 markus 658:
1.364 djm 659: /* Read systemwide configuration file after user config. */
1.223 deraadt 660: (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
1.210 djm 661: &options, 0);
1.139 markus 662: }
1.31 markus 663:
664: /* Fill configuration defaults. */
665: fill_default_options(&options);
666:
1.196 djm 667: channel_set_af(options.address_family);
668:
1.31 markus 669: /* reinit */
1.325 markus 670: log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1.370 djm 671:
672: if (options.request_tty == REQUEST_TTY_YES ||
673: options.request_tty == REQUEST_TTY_FORCE)
674: tty_flag = 1;
675:
676: /* Allocate a tty by default if no command specified. */
677: if (buffer_len(&command) == 0)
678: tty_flag = options.request_tty != REQUEST_TTY_NO;
679:
680: /* Force no tty */
681: if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0)
682: tty_flag = 0;
683: /* Do not allocate a tty if stdin is not a tty. */
684: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
685: options.request_tty != REQUEST_TTY_FORCE) {
686: if (tty_flag)
687: logit("Pseudo-terminal will not be allocated because "
688: "stdin is not a terminal.");
689: tty_flag = 0;
690: }
1.31 markus 691:
692: if (options.user == NULL)
693: options.user = xstrdup(pw->pw_name);
694:
1.317 dtucker 695: /* Get default port if port has not been set. */
696: if (options.port == 0) {
697: sp = getservbyname(SSH_SERVICE_NAME, "tcp");
698: options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
699: }
700:
1.356 djm 701: /* preserve host name given on command line for %n expansion */
702: host_arg = host;
1.343 djm 703: if (options.hostname != NULL) {
704: host = percent_expand(options.hostname,
705: "h", host, (char *)NULL);
706: }
707:
1.358 djm 708: if (gethostname(thishost, sizeof(thishost)) == -1)
709: fatal("gethostname: %s", strerror(errno));
710: strlcpy(shorthost, thishost, sizeof(shorthost));
711: shorthost[strcspn(thishost, ".")] = '\0';
712: snprintf(portstr, sizeof(portstr), "%d", options.port);
713:
1.317 dtucker 714: if (options.local_command != NULL) {
715: debug3("expanding LocalCommand: %s", options.local_command);
716: cp = options.local_command;
717: options.local_command = percent_expand(cp, "d", pw->pw_dir,
1.356 djm 718: "h", host, "l", thishost, "n", host_arg, "r", options.user,
1.358 djm 719: "p", portstr, "u", pw->pw_name, "L", shorthost,
720: (char *)NULL);
1.317 dtucker 721: debug3("expanded LocalCommand: %s", options.local_command);
722: xfree(cp);
723: }
1.195 markus 724:
725: /* force lowercase for hostkey matching */
726: if (options.host_key_alias != NULL) {
727: for (p = options.host_key_alias; *p; p++)
728: if (isupper(*p))
1.271 deraadt 729: *p = (char)tolower(*p);
1.246 djm 730: }
731:
1.190 markus 732: if (options.proxy_command != NULL &&
1.304 dtucker 733: strcmp(options.proxy_command, "none") == 0) {
734: xfree(options.proxy_command);
1.190 markus 735: options.proxy_command = NULL;
1.304 dtucker 736: }
1.245 djm 737: if (options.control_path != NULL &&
1.304 dtucker 738: strcmp(options.control_path, "none") == 0) {
739: xfree(options.control_path);
1.245 djm 740: options.control_path = NULL;
1.304 dtucker 741: }
1.31 markus 742:
1.214 djm 743: if (options.control_path != NULL) {
1.241 djm 744: cp = tilde_expand_filename(options.control_path,
745: original_real_uid);
1.304 dtucker 746: xfree(options.control_path);
1.358 djm 747: options.control_path = percent_expand(cp, "h", host,
748: "l", thishost, "n", host_arg, "r", options.user,
749: "p", portstr, "u", pw->pw_name, "L", shorthost,
750: (char *)NULL);
1.241 djm 751: xfree(cp);
1.214 djm 752: }
1.312 djm 753: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 754: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 755: if (options.control_path != NULL)
1.312 djm 756: muxclient(options.control_path);
1.214 djm 757:
1.303 djm 758: timeout_ms = options.connection_timeout * 1000;
759:
1.77 markus 760: /* Open a connection to the remote host. */
1.203 djm 761: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 762: options.address_family, options.connection_attempts, &timeout_ms,
763: options.tcp_keep_alive,
1.177 markus 764: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 765: options.proxy_command) != 0)
1.257 dtucker 766: exit(255);
1.31 markus 767:
1.303 djm 768: if (timeout_ms > 0)
769: debug3("timeout: %d ms remain after connect", timeout_ms);
770:
1.33 markus 771: /*
772: * If we successfully made the connection, load the host private key
773: * in case we will need it later for combined rsa-rhosts
774: * authentication. This must be done before releasing extra
775: * privileges, because the file is only readable by root.
1.174 markus 776: * If we cannot access the private keys, load the public keys
777: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 778: */
1.112 markus 779: sensitive_data.nkeys = 0;
780: sensitive_data.keys = NULL;
1.173 markus 781: sensitive_data.external_keysign = 0;
1.178 markus 782: if (options.rhosts_rsa_authentication ||
783: options.hostbased_authentication) {
1.349 djm 784: sensitive_data.nkeys = 7;
1.274 deraadt 785: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 786: sizeof(Key));
1.177 markus 787:
788: PRIV_START;
1.112 markus 789: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 790: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.345 djm 791: sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
792: _PATH_HOST_DSA_KEY_FILE, "", NULL);
1.349 djm 793: sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
794: _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
795: sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1.345 djm 796: _PATH_HOST_RSA_KEY_FILE, "", NULL);
1.349 djm 797: sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
1.276 dtucker 798: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.349 djm 799: sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
800: _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
801: sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
1.276 dtucker 802: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 803: PRIV_END;
1.173 markus 804:
1.181 markus 805: if (options.hostbased_authentication == 1 &&
806: sensitive_data.keys[0] == NULL &&
1.349 djm 807: sensitive_data.keys[4] == NULL &&
808: sensitive_data.keys[5] == NULL &&
809: sensitive_data.keys[6] == NULL) {
1.345 djm 810: sensitive_data.keys[1] = key_load_cert(
811: _PATH_HOST_DSA_KEY_FILE);
812: sensitive_data.keys[2] = key_load_cert(
1.349 djm 813: _PATH_HOST_ECDSA_KEY_FILE);
814: sensitive_data.keys[3] = key_load_cert(
1.345 djm 815: _PATH_HOST_RSA_KEY_FILE);
1.349 djm 816: sensitive_data.keys[4] = key_load_public(
1.173 markus 817: _PATH_HOST_DSA_KEY_FILE, NULL);
1.349 djm 818: sensitive_data.keys[5] = key_load_public(
819: _PATH_HOST_ECDSA_KEY_FILE, NULL);
820: sensitive_data.keys[6] = key_load_public(
1.173 markus 821: _PATH_HOST_RSA_KEY_FILE, NULL);
822: sensitive_data.external_keysign = 1;
823: }
1.31 markus 824: }
1.33 markus 825: /*
826: * Get rid of any extra privileges that we may have. We will no
827: * longer need them. Also, extra privileges could make it very hard
828: * to read identity files and other non-world-readable files from the
829: * user's home directory if it happens to be on a NFS volume where
830: * root is mapped to nobody.
831: */
1.225 dtucker 832: if (original_effective_uid == 0) {
833: PRIV_START;
834: permanently_set_uid(pw);
835: }
1.31 markus 836:
1.33 markus 837: /*
838: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 839: * directory if it doesn't already exist.
1.33 markus 840: */
1.367 djm 841: if (config == NULL) {
842: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
843: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
844: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
845: if (mkdir(buf, 0700) < 0)
846: error("Could not create directory '%.200s'.",
847: buf);
848: }
1.31 markus 849:
1.104 markus 850: /* load options.identity_files */
851: load_public_identity_files();
852:
853: /* Expand ~ in known host file names. */
1.361 djm 854: tilde_expand_paths(options.system_hostfiles,
855: options.num_system_hostfiles);
856: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 857:
858: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 859: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 860:
1.316 djm 861: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 862: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 863: options.port, pw, timeout_ms);
1.339 djm 864:
865: if (packet_connection_is_on_socket()) {
866: verbose("Authenticated to %s ([%s]:%d).", host,
867: get_remote_ipaddr(), get_remote_port());
868: } else {
869: verbose("Authenticated to %s (via proxy).", host);
870: }
1.31 markus 871:
1.112 markus 872: /* We no longer need the private host keys. Clear them now. */
873: if (sensitive_data.nkeys != 0) {
874: for (i = 0; i < sensitive_data.nkeys; i++) {
875: if (sensitive_data.keys[i] != NULL) {
876: /* Destroys contents safely */
877: debug3("clear hostkey %d", i);
878: key_free(sensitive_data.keys[i]);
879: sensitive_data.keys[i] = NULL;
880: }
881: }
882: xfree(sensitive_data.keys);
1.134 markus 883: }
884: for (i = 0; i < options.num_identity_files; i++) {
885: if (options.identity_files[i]) {
886: xfree(options.identity_files[i]);
887: options.identity_files[i] = NULL;
888: }
889: if (options.identity_keys[i]) {
890: key_free(options.identity_keys[i]);
891: options.identity_keys[i] = NULL;
892: }
1.112 markus 893: }
1.31 markus 894:
1.45 markus 895: exit_status = compat20 ? ssh_session2() : ssh_session();
896: packet_close();
1.186 djm 897:
1.312 djm 898: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 899: unlink(options.control_path);
900:
1.353 djm 901: /* Kill ProxyCommand if it is running. */
902: ssh_kill_proxy_command();
1.186 djm 903:
1.45 markus 904: return exit_status;
905: }
906:
1.344 djm 907: static void
908: control_persist_detach(void)
909: {
910: pid_t pid;
1.346 djm 911: int devnull;
1.344 djm 912:
913: debug("%s: backgrounding master process", __func__);
914:
915: /*
916: * master (current process) into the background, and make the
917: * foreground process a client of the backgrounded master.
918: */
919: switch ((pid = fork())) {
920: case -1:
921: fatal("%s: fork: %s", __func__, strerror(errno));
922: case 0:
923: /* Child: master process continues mainloop */
924: break;
925: default:
926: /* Parent: set up mux slave to connect to backgrounded master */
927: debug2("%s: background process is %ld", __func__, (long)pid);
928: stdin_null_flag = ostdin_null_flag;
1.359 djm 929: options.request_tty = orequest_tty;
1.344 djm 930: tty_flag = otty_flag;
931: close(muxserver_sock);
932: muxserver_sock = -1;
1.351 markus 933: options.control_master = SSHCTL_MASTER_NO;
1.344 djm 934: muxclient(options.control_path);
935: /* muxclient() doesn't return on success. */
936: fatal("Failed to connect to new control master");
937: }
1.346 djm 938: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
939: error("%s: open(\"/dev/null\"): %s", __func__,
940: strerror(errno));
941: } else {
942: if (dup2(devnull, STDIN_FILENO) == -1 ||
943: dup2(devnull, STDOUT_FILENO) == -1)
944: error("%s: dup2: %s", __func__, strerror(errno));
945: if (devnull > STDERR_FILENO)
946: close(devnull);
947: }
1.362 djm 948: setproctitle("%s [mux]", options.control_path);
1.344 djm 949: }
950:
951: /* Do fork() after authentication. Used by "ssh -f" */
952: static void
953: fork_postauth(void)
954: {
955: if (need_controlpersist_detach)
956: control_persist_detach();
957: debug("forking to background");
958: fork_after_authentication_flag = 0;
959: if (daemon(1, 1) < 0)
960: fatal("daemon() failed: %.200s", strerror(errno));
961: }
962:
1.315 djm 963: /* Callback for remote forward global requests */
964: static void
965: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
966: {
967: Forward *rfwd = (Forward *)ctxt;
968:
1.324 djm 969: /* XXX verbose() on failure? */
1.315 djm 970: debug("remote forward %s for: listen %d, connect %s:%d",
971: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
972: rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
1.366 markus 973: if (rfwd->listen_port == 0) {
974: if (type == SSH2_MSG_REQUEST_SUCCESS) {
975: rfwd->allocated_port = packet_get_int();
976: logit("Allocated port %u for remote forward to %s:%d",
977: rfwd->allocated_port,
978: rfwd->connect_host, rfwd->connect_port);
979: channel_update_permitted_opens(rfwd->handle,
980: rfwd->allocated_port);
981: } else {
982: channel_update_permitted_opens(rfwd->handle, -1);
983: }
1.324 djm 984: }
985:
1.315 djm 986: if (type == SSH2_MSG_REQUEST_FAILURE) {
987: if (options.exit_on_forward_failure)
988: fatal("Error: remote port forwarding failed for "
989: "listen port %d", rfwd->listen_port);
990: else
991: logit("Warning: remote port forwarding failed for "
992: "listen port %d", rfwd->listen_port);
993: }
1.318 djm 994: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 995: debug("All remote forwarding requests processed");
1.344 djm 996: if (fork_after_authentication_flag)
997: fork_postauth();
1.318 djm 998: }
1.315 djm 999: }
1000:
1.126 itojun 1001: static void
1.331 dtucker 1002: client_cleanup_stdio_fwd(int id, void *arg)
1003: {
1004: debug("stdio forwarding: done");
1005: cleanup_exit(0);
1006: }
1007:
1.368 djm 1008: static void
1009: ssh_init_stdio_forwarding(void)
1.331 dtucker 1010: {
1011: Channel *c;
1.332 djm 1012: int in, out;
1.331 dtucker 1013:
1.368 djm 1014: if (stdio_forward_host == NULL)
1015: return;
1016: if (!compat20)
1017: fatal("stdio forwarding require Protocol 2");
1018:
1019: debug3("%s: %s:%d", __func__, stdio_forward_host, stdio_forward_port);
1.332 djm 1020:
1.368 djm 1021: if ((in = dup(STDIN_FILENO)) < 0 ||
1022: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1023: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.368 djm 1024: if ((c = channel_connect_stdio_fwd(stdio_forward_host,
1025: stdio_forward_port, in, out)) == NULL)
1026: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.331 dtucker 1027: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1028: }
1029:
1030: static void
1.70 markus 1031: ssh_init_forwarding(void)
1032: {
1.86 markus 1033: int success = 0;
1.70 markus 1034: int i;
1.331 dtucker 1035:
1.70 markus 1036: /* Initiate local TCP/IP port forwardings. */
1037: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1038: debug("Local connections to %.200s:%d forwarded to remote "
1039: "address %.200s:%d",
1.234 deraadt 1040: (options.local_forwards[i].listen_host == NULL) ?
1041: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1042: options.local_forwards[i].listen_host,
1043: options.local_forwards[i].listen_port,
1044: options.local_forwards[i].connect_host,
1045: options.local_forwards[i].connect_port);
1.158 markus 1046: success += channel_setup_local_fwd_listener(
1.232 djm 1047: options.local_forwards[i].listen_host,
1048: options.local_forwards[i].listen_port,
1049: options.local_forwards[i].connect_host,
1050: options.local_forwards[i].connect_port,
1.70 markus 1051: options.gateway_ports);
1052: }
1.283 markus 1053: if (i > 0 && success != i && options.exit_on_forward_failure)
1054: fatal("Could not request local forwarding.");
1.86 markus 1055: if (i > 0 && success == 0)
1056: error("Could not request local forwarding.");
1.70 markus 1057:
1058: /* Initiate remote TCP/IP port forwardings. */
1059: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1060: debug("Remote connections from %.200s:%d forwarded to "
1061: "local address %.200s:%d",
1.248 djm 1062: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1063: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1064: options.remote_forwards[i].listen_port,
1065: options.remote_forwards[i].connect_host,
1066: options.remote_forwards[i].connect_port);
1.366 markus 1067: options.remote_forwards[i].handle =
1068: channel_request_remote_forwarding(
1.232 djm 1069: options.remote_forwards[i].listen_host,
1070: options.remote_forwards[i].listen_port,
1071: options.remote_forwards[i].connect_host,
1.366 markus 1072: options.remote_forwards[i].connect_port);
1073: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1074: if (options.exit_on_forward_failure)
1075: fatal("Could not request remote forwarding.");
1076: else
1077: logit("Warning: Could not request remote "
1078: "forwarding.");
1.366 markus 1079: } else {
1080: client_register_global_confirm(ssh_confirm_remote_forward,
1081: &options.remote_forwards[i]);
1.283 markus 1082: }
1.70 markus 1083: }
1.301 djm 1084:
1085: /* Initiate tunnel forwarding. */
1086: if (options.tun_open != SSH_TUNMODE_NO) {
1087: if (client_request_tun_fwd(options.tun_open,
1088: options.tun_local, options.tun_remote) == -1) {
1089: if (options.exit_on_forward_failure)
1090: fatal("Could not request tunnel forwarding.");
1091: else
1092: error("Could not request tunnel forwarding.");
1093: }
1094: }
1.70 markus 1095: }
1096:
1.126 itojun 1097: static void
1.70 markus 1098: check_agent_present(void)
1099: {
1100: if (options.forward_agent) {
1.254 djm 1101: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 1102: if (!ssh_agent_present())
1.70 markus 1103: options.forward_agent = 0;
1104: }
1105: }
1106:
1.126 itojun 1107: static int
1.45 markus 1108: ssh_session(void)
1109: {
1110: int type;
1111: int interactive = 0;
1112: int have_tty = 0;
1113: struct winsize ws;
1114: char *cp;
1.243 djm 1115: const char *display;
1.45 markus 1116:
1.31 markus 1117: /* Enable compression if requested. */
1118: if (options.compression) {
1.316 djm 1119: debug("Requesting compression at level %d.",
1120: options.compression_level);
1.31 markus 1121:
1.316 djm 1122: if (options.compression_level < 1 ||
1123: options.compression_level > 9)
1124: fatal("Compression level must be from 1 (fast) to "
1125: "9 (slow, best).");
1.31 markus 1126:
1127: /* Send the request. */
1128: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1129: packet_put_int(options.compression_level);
1130: packet_send();
1131: packet_write_wait();
1.156 markus 1132: type = packet_read();
1.31 markus 1133: if (type == SSH_SMSG_SUCCESS)
1134: packet_start_compression(options.compression_level);
1135: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1136: logit("Warning: Remote host refused compression.");
1.31 markus 1137: else
1.316 djm 1138: packet_disconnect("Protocol error waiting for "
1139: "compression response.");
1.31 markus 1140: }
1141: /* Allocate a pseudo tty if appropriate. */
1142: if (tty_flag) {
1143: debug("Requesting pty.");
1144:
1145: /* Start the packet. */
1146: packet_start(SSH_CMSG_REQUEST_PTY);
1147:
1148: /* Store TERM in the packet. There is no limit on the
1149: length of the string. */
1150: cp = getenv("TERM");
1151: if (!cp)
1152: cp = "";
1.124 markus 1153: packet_put_cstring(cp);
1.31 markus 1154:
1155: /* Store window size in the packet. */
1156: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1157: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1158: packet_put_int((u_int)ws.ws_row);
1159: packet_put_int((u_int)ws.ws_col);
1160: packet_put_int((u_int)ws.ws_xpixel);
1161: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1162:
1163: /* Store tty modes in the packet. */
1.115 stevesk 1164: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1165:
1166: /* Send the packet, and wait for it to leave. */
1167: packet_send();
1168: packet_write_wait();
1169:
1170: /* Read response from the server. */
1.156 markus 1171: type = packet_read();
1.43 markus 1172: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1173: interactive = 1;
1.45 markus 1174: have_tty = 1;
1.43 markus 1175: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1176: logit("Warning: Remote host failed or refused to "
1177: "allocate a pseudo tty.");
1.31 markus 1178: else
1.316 djm 1179: packet_disconnect("Protocol error waiting for pty "
1180: "request response.");
1.31 markus 1181: }
1182: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1183: display = getenv("DISPLAY");
1184: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1185: char *proto, *data;
1.50 markus 1186: /* Get reasonable local authentication information. */
1.243 djm 1187: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1188: options.forward_x11_trusted,
1189: options.forward_x11_timeout,
1190: &proto, &data);
1.50 markus 1191: /* Request forwarding with authentication spoofing. */
1.316 djm 1192: debug("Requesting X11 forwarding with authentication "
1193: "spoofing.");
1.363 djm 1194: x11_request_forwarding_with_spoofing(0, display, proto,
1195: data, 0);
1.31 markus 1196: /* Read response from the server. */
1.156 markus 1197: type = packet_read();
1.31 markus 1198: if (type == SSH_SMSG_SUCCESS) {
1199: interactive = 1;
1.50 markus 1200: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1201: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1202: } else {
1.316 djm 1203: packet_disconnect("Protocol error waiting for X11 "
1204: "forwarding");
1.50 markus 1205: }
1.31 markus 1206: }
1207: /* Tell the packet module whether this is an interactive session. */
1.354 djm 1208: packet_set_interactive(interactive,
1209: options.ip_qos_interactive, options.ip_qos_bulk);
1.31 markus 1210:
1211: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1212: check_agent_present();
1213:
1.31 markus 1214: if (options.forward_agent) {
1215: debug("Requesting authentication agent forwarding.");
1216: auth_request_forwarding();
1217:
1218: /* Read response from the server. */
1.156 markus 1219: type = packet_read();
1.155 markus 1220: packet_check_eom();
1.31 markus 1221: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1222: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1223: }
1224:
1.70 markus 1225: /* Initiate port forwardings. */
1.368 djm 1226: ssh_init_stdio_forwarding();
1.70 markus 1227: ssh_init_forwarding();
1.305 dtucker 1228:
1229: /* Execute a local command */
1230: if (options.local_command != NULL &&
1231: options.permit_local_command)
1232: ssh_local_cmd(options.local_command);
1.34 markus 1233:
1.318 djm 1234: /*
1235: * If requested and we are not interested in replies to remote
1236: * forwarding requests, then let ssh continue in the background.
1237: */
1.344 djm 1238: if (fork_after_authentication_flag) {
1239: if (options.exit_on_forward_failure &&
1240: options.num_remote_forwards > 0) {
1241: debug("deferring postauth fork until remote forward "
1242: "confirmation received");
1243: } else
1244: fork_postauth();
1.318 djm 1245: }
1.31 markus 1246:
1.33 markus 1247: /*
1248: * If a command was specified on the command line, execute the
1249: * command now. Otherwise request the server to start a shell.
1250: */
1.31 markus 1251: if (buffer_len(&command) > 0) {
1252: int len = buffer_len(&command);
1253: if (len > 900)
1254: len = 900;
1.316 djm 1255: debug("Sending command: %.*s", len,
1256: (u_char *)buffer_ptr(&command));
1.31 markus 1257: packet_start(SSH_CMSG_EXEC_CMD);
1258: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1259: packet_send();
1260: packet_write_wait();
1261: } else {
1262: debug("Requesting shell.");
1263: packet_start(SSH_CMSG_EXEC_SHELL);
1264: packet_send();
1265: packet_write_wait();
1266: }
1267:
1268: /* Enter the interactive session. */
1.119 stevesk 1269: return client_loop(have_tty, tty_flag ?
1270: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1271: }
1272:
1.214 djm 1273: /* request pty/x11/agent/tcpfwd/shell for channel */
1274: static void
1.337 djm 1275: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1276: {
1.215 djm 1277: extern char **environ;
1.243 djm 1278: const char *display;
1279: int interactive = tty_flag;
1.337 djm 1280:
1281: if (!success)
1282: return; /* No need for error message, channels code sens one */
1.215 djm 1283:
1.248 djm 1284: display = getenv("DISPLAY");
1.243 djm 1285: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1286: char *proto, *data;
1.50 markus 1287: /* Get reasonable local authentication information. */
1.243 djm 1288: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1289: options.forward_x11_trusted,
1290: options.forward_x11_timeout, &proto, &data);
1.50 markus 1291: /* Request forwarding with authentication spoofing. */
1.316 djm 1292: debug("Requesting X11 forwarding with authentication "
1293: "spoofing.");
1.363 djm 1294: x11_request_forwarding_with_spoofing(id, display, proto,
1295: data, 1);
1296: client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
1297: /* XXX exit_on_forward_failure */
1.80 markus 1298: interactive = 1;
1.50 markus 1299: }
1300:
1.70 markus 1301: check_agent_present();
1302: if (options.forward_agent) {
1303: debug("Requesting authentication agent forwarding.");
1304: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1305: packet_send();
1.212 djm 1306: }
1.369 dtucker 1307:
1308: /* Tell the packet module whether this is an interactive session. */
1309: packet_set_interactive(interactive,
1310: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1311:
1.214 djm 1312: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1313: NULL, fileno(stdin), &command, environ);
1.45 markus 1314: }
1315:
1.143 markus 1316: /* open new channel for a session */
1.126 itojun 1317: static int
1.143 markus 1318: ssh_session2_open(void)
1.45 markus 1319: {
1.118 markus 1320: Channel *c;
1321: int window, packetmax, in, out, err;
1.60 markus 1322:
1.62 markus 1323: if (stdin_null_flag) {
1.93 itojun 1324: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1325: } else {
1326: in = dup(STDIN_FILENO);
1327: }
1.60 markus 1328: out = dup(STDOUT_FILENO);
1329: err = dup(STDERR_FILENO);
1.45 markus 1330:
1331: if (in < 0 || out < 0 || err < 0)
1.62 markus 1332: fatal("dup() in/out/err failed");
1.45 markus 1333:
1.69 markus 1334: /* enable nonblocking unless tty */
1335: if (!isatty(in))
1336: set_nonblock(in);
1337: if (!isatty(out))
1338: set_nonblock(out);
1339: if (!isatty(err))
1340: set_nonblock(err);
1341:
1.65 markus 1342: window = CHAN_SES_WINDOW_DEFAULT;
1343: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1344: if (tty_flag) {
1345: window >>= 1;
1346: packetmax >>= 1;
1.45 markus 1347: }
1.118 markus 1348: c = channel_new(
1.45 markus 1349: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1350: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1351: "client-session", /*nonblock*/0);
1.45 markus 1352:
1.143 markus 1353: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1354:
1.122 markus 1355: channel_send_open(c->self);
1.143 markus 1356: if (!no_shell_flag)
1.310 djm 1357: channel_register_open_confirm(c->self,
1358: ssh_session2_setup, NULL);
1.106 markus 1359:
1.118 markus 1360: return c->self;
1.106 markus 1361: }
1362:
1.126 itojun 1363: static int
1.106 markus 1364: ssh_session2(void)
1365: {
1.143 markus 1366: int id = -1;
1.106 markus 1367:
1368: /* XXX should be pre-session */
1.368 djm 1369: if (!options.control_persist)
1370: ssh_init_stdio_forwarding();
1.106 markus 1371: ssh_init_forwarding();
1372:
1.344 djm 1373: /* Start listening for multiplex clients */
1374: muxserver_listen();
1375:
1376: /*
1.368 djm 1377: * If we are in control persist mode and have a working mux listen
1378: * socket, then prepare to background ourselves and have a foreground
1379: * client attach as a control slave.
1380: * NB. we must save copies of the flags that we override for
1.344 djm 1381: * the backgrounding, since we defer attachment of the slave until
1382: * after the connection is fully established (in particular,
1383: * async rfwd replies have been received for ExitOnForwardFailure).
1384: */
1385: if (options.control_persist && muxserver_sock != -1) {
1386: ostdin_null_flag = stdin_null_flag;
1387: ono_shell_flag = no_shell_flag;
1.359 djm 1388: orequest_tty = options.request_tty;
1.344 djm 1389: otty_flag = tty_flag;
1390: stdin_null_flag = 1;
1391: no_shell_flag = 1;
1392: tty_flag = 0;
1393: if (!fork_after_authentication_flag)
1394: need_controlpersist_detach = 1;
1395: fork_after_authentication_flag = 1;
1396: }
1.368 djm 1397: /*
1398: * ControlPersist mux listen socket setup failed, attempt the
1399: * stdio forward setup that we skipped earlier.
1400: */
1401: if (options.control_persist && muxserver_sock == -1)
1402: ssh_init_stdio_forwarding();
1.344 djm 1403:
1.143 markus 1404: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1405: id = ssh_session2_open();
1.314 djm 1406:
1407: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1408: if (options.control_master == SSHCTL_MASTER_NO &&
1409: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1410: debug("Requesting no-more-sessions@openssh.com");
1411: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1412: packet_put_cstring("no-more-sessions@openssh.com");
1413: packet_put_char(0);
1414: packet_send();
1415: }
1.255 reyk 1416:
1417: /* Execute a local command */
1418: if (options.local_command != NULL &&
1419: options.permit_local_command)
1420: ssh_local_cmd(options.local_command);
1.301 djm 1421:
1.342 djm 1422: /*
1423: * If requested and we are not interested in replies to remote
1424: * forwarding requests, then let ssh continue in the background.
1425: */
1.344 djm 1426: if (fork_after_authentication_flag) {
1427: if (options.exit_on_forward_failure &&
1428: options.num_remote_forwards > 0) {
1429: debug("deferring postauth fork until remote forward "
1430: "confirmation received");
1431: } else
1432: fork_postauth();
1.318 djm 1433: }
1.327 andreas 1434:
1435: if (options.use_roaming)
1436: request_roaming();
1.31 markus 1437:
1.119 stevesk 1438: return client_loop(tty_flag, tty_flag ?
1439: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1440: }
1441:
1.126 itojun 1442: static void
1.104 markus 1443: load_public_identity_files(void)
1444: {
1.275 djm 1445: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1446: char *pwdir = NULL, *pwname = NULL;
1.167 markus 1447: int i = 0;
1.104 markus 1448: Key *public;
1.275 djm 1449: struct passwd *pw;
1.335 djm 1450: u_int n_ids;
1451: char *identity_files[SSH_MAX_IDENTITY_FILES];
1452: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.333 markus 1453: #ifdef ENABLE_PKCS11
1.167 markus 1454: Key **keys;
1.333 markus 1455: int nkeys;
1.335 djm 1456: #endif /* PKCS11 */
1.104 markus 1457:
1.335 djm 1458: n_ids = 0;
1459: bzero(identity_files, sizeof(identity_files));
1460: bzero(identity_keys, sizeof(identity_keys));
1461:
1462: #ifdef ENABLE_PKCS11
1.333 markus 1463: if (options.pkcs11_provider != NULL &&
1.167 markus 1464: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1465: (pkcs11_init(!options.batch_mode) == 0) &&
1466: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1467: &keys)) > 0) {
1468: for (i = 0; i < nkeys; i++) {
1.335 djm 1469: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1470: key_free(keys[i]);
1471: continue;
1472: }
1473: identity_keys[n_ids] = keys[i];
1474: identity_files[n_ids] =
1.333 markus 1475: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 1476: n_ids++;
1.167 markus 1477: }
1478: xfree(keys);
1.127 markus 1479: }
1.333 markus 1480: #endif /* ENABLE_PKCS11 */
1.275 djm 1481: if ((pw = getpwuid(original_real_uid)) == NULL)
1482: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 1483: pwname = xstrdup(pw->pw_name);
1484: pwdir = xstrdup(pw->pw_dir);
1.275 djm 1485: if (gethostname(thishost, sizeof(thishost)) == -1)
1486: fatal("load_public_identity_files: gethostname: %s",
1487: strerror(errno));
1.335 djm 1488: for (i = 0; i < options.num_identity_files; i++) {
1.373 djm 1489: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
1490: strcasecmp(options.identity_files[i], "none") == 0) {
1.335 djm 1491: xfree(options.identity_files[i]);
1492: continue;
1493: }
1.275 djm 1494: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1495: original_real_uid);
1.306 deraadt 1496: filename = percent_expand(cp, "d", pwdir,
1497: "u", pwname, "l", thishost, "h", host,
1.275 djm 1498: "r", options.user, (char *)NULL);
1499: xfree(cp);
1.131 millert 1500: public = key_load_public(filename, NULL);
1501: debug("identity file %s type %d", filename,
1502: public ? public->type : -1);
1503: xfree(options.identity_files[i]);
1.335 djm 1504: identity_files[n_ids] = filename;
1505: identity_keys[n_ids] = public;
1506:
1507: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1508: continue;
1509:
1510: /* Try to add the certificate variant too */
1511: xasprintf(&cp, "%s-cert", filename);
1512: public = key_load_public(cp, NULL);
1513: debug("identity file %s type %d", cp,
1514: public ? public->type : -1);
1515: if (public == NULL) {
1516: xfree(cp);
1517: continue;
1518: }
1519: if (!key_is_cert(public)) {
1520: debug("%s: key %s type %s is not a certificate",
1521: __func__, cp, key_type(public));
1522: key_free(public);
1523: xfree(cp);
1524: continue;
1525: }
1526: identity_keys[n_ids] = public;
1527: /* point to the original path, most likely the private key */
1528: identity_files[n_ids] = xstrdup(filename);
1529: n_ids++;
1530: }
1531: options.num_identity_files = n_ids;
1532: memcpy(options.identity_files, identity_files, sizeof(identity_files));
1533: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1534:
1.306 deraadt 1535: bzero(pwname, strlen(pwname));
1.307 dtucker 1536: xfree(pwname);
1.306 deraadt 1537: bzero(pwdir, strlen(pwdir));
1.307 dtucker 1538: xfree(pwdir);
1.214 djm 1539: }
1.352 djm 1540:
1541: static void
1542: main_sigchld_handler(int sig)
1543: {
1544: int save_errno = errno;
1545: pid_t pid;
1546: int status;
1547:
1548: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
1549: (pid < 0 && errno == EINTR))
1550: ;
1551:
1552: signal(sig, main_sigchld_handler);
1553: errno = save_errno;
1554: }
1555:
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