Annotation of src/usr.bin/ssh/ssh.c, Revision 1.304
1.304 ! dtucker 1: /* $OpenBSD: ssh.c,v 1.303 2007/09/04 11:15:55 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>
1.294 djm 44: #include <sys/time.h>
1.259 stevesk 45: #include <sys/resource.h>
1.260 stevesk 46: #include <sys/ioctl.h>
1.262 stevesk 47: #include <sys/types.h>
1.280 stevesk 48: #include <sys/socket.h>
1.262 stevesk 49: #include <sys/un.h>
1.264 stevesk 50: #include <sys/stat.h>
1.258 stevesk 51:
1.265 stevesk 52: #include <ctype.h>
1.285 stevesk 53: #include <errno.h>
1.281 stevesk 54: #include <fcntl.h>
1.286 stevesk 55: #include <netdb.h>
1.258 stevesk 56: #include <paths.h>
1.279 stevesk 57: #include <pwd.h>
1.263 stevesk 58: #include <signal.h>
1.287 stevesk 59: #include <stddef.h>
1.291 stevesk 60: #include <stdio.h>
1.290 stevesk 61: #include <stdlib.h>
1.289 stevesk 62: #include <string.h>
1.288 stevesk 63: #include <unistd.h>
1.49 markus 64:
65: #include <openssl/evp.h>
1.72 markus 66: #include <openssl/err.h>
1.1 deraadt 67:
1.293 deraadt 68: #include "xmalloc.h"
1.84 markus 69: #include "ssh.h"
70: #include "ssh1.h"
71: #include "ssh2.h"
72: #include "compat.h"
73: #include "cipher.h"
1.1 deraadt 74: #include "packet.h"
75: #include "buffer.h"
1.123 markus 76: #include "channels.h"
1.49 markus 77: #include "key.h"
1.58 markus 78: #include "authfd.h"
1.49 markus 79: #include "authfile.h"
1.83 markus 80: #include "pathnames.h"
1.214 djm 81: #include "dispatch.h"
1.81 markus 82: #include "clientloop.h"
1.84 markus 83: #include "log.h"
84: #include "readconf.h"
85: #include "sshconnect.h"
86: #include "misc.h"
1.95 markus 87: #include "kex.h"
88: #include "mac.h"
1.213 deraadt 89: #include "sshpty.h"
1.212 djm 90: #include "match.h"
1.214 djm 91: #include "msg.h"
92: #include "monitor_fdpass.h"
1.225 dtucker 93: #include "uidswap.h"
1.278 stevesk 94: #include "version.h"
1.49 markus 95:
1.127 markus 96: #ifdef SMARTCARD
97: #include "scard.h"
1.137 jakob 98: #endif
1.127 markus 99:
1.49 markus 100: extern char *__progname;
1.1 deraadt 101:
1.31 markus 102: /* Flag indicating whether debug mode is on. This can be set on the command line. */
1.1 deraadt 103: int debug_flag = 0;
104:
1.46 markus 105: /* Flag indicating whether a tty should be allocated */
1.1 deraadt 106: int tty_flag = 0;
1.79 markus 107: int no_tty_flag = 0;
108: int force_tty_flag = 0;
1.1 deraadt 109:
1.45 markus 110: /* don't exec a shell */
111: int no_shell_flag = 0;
112:
1.33 markus 113: /*
114: * Flag indicating that nothing should be read from stdin. This can be set
115: * on the command line.
116: */
1.1 deraadt 117: int stdin_null_flag = 0;
118:
1.33 markus 119: /*
120: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 121: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 122: * background.
123: */
1.1 deraadt 124: int fork_after_authentication_flag = 0;
125:
1.33 markus 126: /*
127: * General data structure for command line options and options configurable
128: * in configuration files. See readconf.h.
129: */
1.1 deraadt 130: Options options;
131:
1.139 markus 132: /* optional user configfile */
133: char *config = NULL;
134:
1.33 markus 135: /*
136: * Name of the host we are connecting to. This is the name given on the
137: * command line, or the HostName specified for the user-supplied name in a
138: * configuration file.
139: */
1.1 deraadt 140: char *host;
141:
1.22 provos 142: /* socket address the host resolves to */
1.37 markus 143: struct sockaddr_storage hostaddr;
1.1 deraadt 144:
1.112 markus 145: /* Private host keys. */
1.173 markus 146: Sensitive sensitive_data;
1.1 deraadt 147:
1.10 dugsong 148: /* Original real UID. */
149: uid_t original_real_uid;
1.177 markus 150: uid_t original_effective_uid;
1.1 deraadt 151:
1.45 markus 152: /* command to be executed */
153: Buffer command;
154:
1.85 djm 155: /* Should we execute a command or invoke a subsystem? */
156: int subsystem_flag = 0;
157:
1.170 markus 158: /* # of replies received for global requests */
159: static int client_global_request_id = 0;
160:
1.186 djm 161: /* pid of proxycommand child process */
162: pid_t proxy_command_pid = 0;
163:
1.214 djm 164: /* fd to control socket */
165: int control_fd = -1;
166:
1.229 djm 167: /* Multiplexing control command */
1.240 djm 168: static u_int mux_command = 0;
1.229 djm 169:
1.214 djm 170: /* Only used in control client mode */
171: volatile sig_atomic_t control_client_terminate = 0;
172: u_int control_server_pid = 0;
173:
1.1 deraadt 174: /* Prints a help message to the user. This function never returns. */
175:
1.126 itojun 176: static void
1.93 itojun 177: usage(void)
1.1 deraadt 178: {
1.208 markus 179: fprintf(stderr,
1.297 djm 180: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n"
1.251 jmc 181: " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
1.233 jmc 182: " [-i identity_file] [-L [bind_address:]port:host:hostport]\n"
1.232 djm 183: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 184: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.277 stevesk 185: " [-w local_tun[:remote_tun]] [user@]hostname [command]\n"
1.208 markus 186: );
1.257 dtucker 187: exit(255);
1.1 deraadt 188: }
189:
1.126 itojun 190: static int ssh_session(void);
191: static int ssh_session2(void);
192: static void load_public_identity_files(void);
1.214 djm 193: static void control_client(const char *path);
1.45 markus 194:
1.32 deraadt 195: /*
196: * Main program for the ssh client.
197: */
1.2 provos 198: int
199: main(int ac, char **av)
1.1 deraadt 200: {
1.178 markus 201: int i, opt, exit_status;
1.205 markus 202: char *p, *cp, *line, buf[256];
1.31 markus 203: struct stat st;
1.98 markus 204: struct passwd *pw;
1.303 djm 205: int dummy, timeout_ms;
1.144 stevesk 206: extern int optind, optreset;
207: extern char *optarg;
1.244 djm 208: struct servent *sp;
1.232 djm 209: Forward fwd;
1.250 djm 210:
211: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
212: sanitise_stdfd();
1.31 markus 213:
1.33 markus 214: /*
215: * Save the original real uid. It will be needed later (uid-swapping
216: * may clobber the real uid).
217: */
1.31 markus 218: original_real_uid = getuid();
219: original_effective_uid = geteuid();
220:
1.184 stevesk 221: /*
222: * Use uid-swapping to give up root privileges for the duration of
223: * option processing. We will re-instantiate the rights when we are
224: * ready to create the privileged port, and will permanently drop
225: * them when the port has been created (actually, when the connection
226: * has been made, as we may need to create the port several times).
227: */
228: PRIV_END;
229:
1.31 markus 230: /* If we are installed setuid root be careful to not drop core. */
231: if (original_real_uid != original_effective_uid) {
232: struct rlimit rlim;
233: rlim.rlim_cur = rlim.rlim_max = 0;
234: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
235: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 236: }
1.107 markus 237: /* Get user data. */
238: pw = getpwuid(original_real_uid);
239: if (!pw) {
1.191 itojun 240: logit("You don't exist, go away!");
1.257 dtucker 241: exit(255);
1.107 markus 242: }
243: /* Take a copy of the returned structure. */
244: pw = pwcopy(pw);
1.31 markus 245:
1.33 markus 246: /*
247: * Set our umask to something reasonable, as some files are created
248: * with the default umask. This will make them world-readable but
249: * writable only by the owner, which is ok for all files for which we
250: * don't set the modes explicitly.
251: */
1.31 markus 252: umask(022);
253:
254: /* Initialize option structure to indicate that no values have been set. */
255: initialize_options(&options);
256:
257: /* Parse command-line arguments. */
258: host = NULL;
259:
1.266 djm 260: again:
1.128 fgsch 261: while ((opt = getopt(ac, av,
1.297 djm 262: "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:KL:MNO:PR:S:TVw:XY")) != -1) {
1.31 markus 263: switch (opt) {
1.91 jakob 264: case '1':
265: options.protocol = SSH_PROTO_1;
266: break;
1.47 markus 267: case '2':
268: options.protocol = SSH_PROTO_2;
269: break;
1.37 markus 270: case '4':
1.196 djm 271: options.address_family = AF_INET;
1.37 markus 272: break;
273: case '6':
1.196 djm 274: options.address_family = AF_INET6;
1.37 markus 275: break;
1.31 markus 276: case 'n':
277: stdin_null_flag = 1;
278: break;
279: case 'f':
280: fork_after_authentication_flag = 1;
281: stdin_null_flag = 1;
282: break;
283: case 'x':
284: options.forward_x11 = 0;
285: break;
286: case 'X':
287: options.forward_x11 = 1;
288: break;
1.202 markus 289: case 'Y':
290: options.forward_x11 = 1;
291: options.forward_x11_trusted = 1;
292: break;
1.31 markus 293: case 'g':
294: options.gateway_ports = 1;
295: break;
1.229 djm 296: case 'O':
297: if (strcmp(optarg, "check") == 0)
298: mux_command = SSHMUX_COMMAND_ALIVE_CHECK;
299: else if (strcmp(optarg, "exit") == 0)
300: mux_command = SSHMUX_COMMAND_TERMINATE;
301: else
302: fatal("Invalid multiplex command.");
303: break;
1.183 stevesk 304: case 'P': /* deprecated */
1.31 markus 305: options.use_privileged_port = 0;
306: break;
307: case 'a':
308: options.forward_agent = 0;
1.53 markus 309: break;
310: case 'A':
311: options.forward_agent = 1;
1.31 markus 312: break;
313: case 'k':
1.204 dtucker 314: options.gss_deleg_creds = 0;
1.297 djm 315: break;
316: case 'K':
317: options.gss_authentication = 1;
318: options.gss_deleg_creds = 1;
1.31 markus 319: break;
320: case 'i':
321: if (stat(optarg, &st) < 0) {
1.128 fgsch 322: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 323: "not accessible: %s.\n", optarg,
324: strerror(errno));
1.31 markus 325: break;
326: }
1.128 fgsch 327: if (options.num_identity_files >=
328: SSH_MAX_IDENTITY_FILES)
329: fatal("Too many identity files specified "
330: "(max %d)", SSH_MAX_IDENTITY_FILES);
331: options.identity_files[options.num_identity_files++] =
332: xstrdup(optarg);
1.31 markus 333: break;
1.127 markus 334: case 'I':
335: #ifdef SMARTCARD
1.133 markus 336: options.smartcard_device = xstrdup(optarg);
1.137 jakob 337: #else
1.127 markus 338: fprintf(stderr, "no support for smartcards.\n");
1.137 jakob 339: #endif
1.127 markus 340: break;
1.31 markus 341: case 't':
1.79 markus 342: if (tty_flag)
343: force_tty_flag = 1;
1.31 markus 344: tty_flag = 1;
345: break;
346: case 'v':
1.197 markus 347: if (debug_flag == 0) {
1.66 markus 348: debug_flag = 1;
349: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 350: } else {
351: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
352: options.log_level++;
1.66 markus 353: break;
1.197 markus 354: }
1.227 deraadt 355: /* FALLTHROUGH */
1.31 markus 356: case 'V':
1.209 markus 357: fprintf(stderr, "%s, %s\n",
358: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 359: if (opt == 'V')
360: exit(0);
361: break;
1.255 reyk 362: case 'w':
1.256 reyk 363: if (options.tun_open == -1)
364: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 365: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 366: if (options.tun_local == SSH_TUNID_ERR) {
1.255 reyk 367: fprintf(stderr, "Bad tun device '%s'\n", optarg);
1.257 dtucker 368: exit(255);
1.255 reyk 369: }
370: break;
1.31 markus 371: case 'q':
372: options.log_level = SYSLOG_LEVEL_QUIET;
373: break;
374: case 'e':
375: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 376: (u_char) optarg[1] >= 64 &&
377: (u_char) optarg[1] < 128)
1.78 markus 378: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 379: else if (strlen(optarg) == 1)
1.78 markus 380: options.escape_char = (u_char) optarg[0];
1.31 markus 381: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 382: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 383: else {
1.128 fgsch 384: fprintf(stderr, "Bad escape character '%s'.\n",
385: optarg);
1.257 dtucker 386: exit(255);
1.31 markus 387: }
388: break;
389: case 'c':
1.49 markus 390: if (ciphers_valid(optarg)) {
391: /* SSH2 only */
392: options.ciphers = xstrdup(optarg);
1.224 markus 393: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 394: } else {
395: /* SSH1 only */
1.74 markus 396: options.cipher = cipher_number(optarg);
397: if (options.cipher == -1) {
1.128 fgsch 398: fprintf(stderr,
399: "Unknown cipher type '%s'\n",
400: optarg);
1.257 dtucker 401: exit(255);
1.49 markus 402: }
1.128 fgsch 403: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 404: options.ciphers = "3des-cbc";
1.128 fgsch 405: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 406: options.ciphers = "blowfish-cbc";
1.128 fgsch 407: else
1.74 markus 408: options.ciphers = (char *)-1;
1.95 markus 409: }
410: break;
411: case 'm':
412: if (mac_valid(optarg))
413: options.macs = xstrdup(optarg);
414: else {
1.128 fgsch 415: fprintf(stderr, "Unknown mac type '%s'\n",
416: optarg);
1.257 dtucker 417: exit(255);
1.31 markus 418: }
419: break;
1.214 djm 420: case 'M':
1.242 djm 421: if (options.control_master == SSHCTL_MASTER_YES)
422: options.control_master = SSHCTL_MASTER_ASK;
423: else
424: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 425: break;
1.31 markus 426: case 'p':
1.113 stevesk 427: options.port = a2port(optarg);
428: if (options.port == 0) {
1.109 markus 429: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 430: exit(255);
1.109 markus 431: }
1.31 markus 432: break;
433: case 'l':
434: options.user = optarg;
435: break;
1.141 stevesk 436:
437: case 'L':
1.232 djm 438: if (parse_forward(&fwd, optarg))
439: add_local_forward(&options, &fwd);
440: else {
1.128 fgsch 441: fprintf(stderr,
1.232 djm 442: "Bad local forwarding specification '%s'\n",
1.128 fgsch 443: optarg);
1.257 dtucker 444: exit(255);
1.31 markus 445: }
1.232 djm 446: break;
447:
448: case 'R':
449: if (parse_forward(&fwd, optarg)) {
450: add_remote_forward(&options, &fwd);
451: } else {
1.128 fgsch 452: fprintf(stderr,
1.232 djm 453: "Bad remote forwarding specification "
454: "'%s'\n", optarg);
1.257 dtucker 455: exit(255);
1.31 markus 456: }
457: break;
1.108 markus 458:
459: case 'D':
1.232 djm 460: cp = p = xstrdup(optarg);
461: memset(&fwd, '\0', sizeof(fwd));
462: fwd.connect_host = "socks";
463: if ((fwd.listen_host = hpdelim(&cp)) == NULL) {
464: fprintf(stderr, "Bad dynamic forwarding "
465: "specification '%.100s'\n", optarg);
1.257 dtucker 466: exit(255);
1.232 djm 467: }
468: if (cp != NULL) {
469: fwd.listen_port = a2port(cp);
470: fwd.listen_host = cleanhostname(fwd.listen_host);
471: } else {
472: fwd.listen_port = a2port(fwd.listen_host);
1.249 djm 473: fwd.listen_host = NULL;
1.232 djm 474: }
475:
476: if (fwd.listen_port == 0) {
1.128 fgsch 477: fprintf(stderr, "Bad dynamic port '%s'\n",
478: optarg);
1.257 dtucker 479: exit(255);
1.109 markus 480: }
1.232 djm 481: add_local_forward(&options, &fwd);
482: xfree(p);
1.108 markus 483: break;
484:
1.31 markus 485: case 'C':
486: options.compression = 1;
487: break;
1.45 markus 488: case 'N':
489: no_shell_flag = 1;
490: no_tty_flag = 1;
491: break;
492: case 'T':
493: no_tty_flag = 1;
494: break;
1.31 markus 495: case 'o':
496: dummy = 1;
1.205 markus 497: line = xstrdup(optarg);
1.128 fgsch 498: if (process_config_line(&options, host ? host : "",
1.205 markus 499: line, "command-line", 0, &dummy) != 0)
1.257 dtucker 500: exit(255);
1.205 markus 501: xfree(line);
1.31 markus 502: break;
1.85 djm 503: case 's':
504: subsystem_flag = 1;
1.117 markus 505: break;
1.214 djm 506: case 'S':
507: if (options.control_path != NULL)
508: free(options.control_path);
509: options.control_path = xstrdup(optarg);
510: break;
1.117 markus 511: case 'b':
512: options.bind_address = optarg;
1.85 djm 513: break;
1.139 markus 514: case 'F':
515: config = optarg;
516: break;
1.31 markus 517: default:
518: usage();
1.1 deraadt 519: }
1.31 markus 520: }
521:
1.128 fgsch 522: ac -= optind;
523: av += optind;
524:
525: if (ac > 0 && !host && **av != '-') {
1.188 markus 526: if (strrchr(*av, '@')) {
1.128 fgsch 527: p = xstrdup(*av);
1.188 markus 528: cp = strrchr(p, '@');
1.128 fgsch 529: if (cp == NULL || cp == p)
530: usage();
531: options.user = p;
532: *cp = '\0';
533: host = ++cp;
534: } else
535: host = *av;
1.189 millert 536: if (ac > 1) {
537: optind = optreset = 1;
1.128 fgsch 538: goto again;
539: }
1.189 millert 540: ac--, av++;
1.128 fgsch 541: }
542:
1.31 markus 543: /* Check that we got a host name. */
544: if (!host)
545: usage();
546:
1.54 markus 547: SSLeay_add_all_algorithms();
1.72 markus 548: ERR_load_crypto_strings();
1.31 markus 549:
550: /* Initialize the command to execute on remote host. */
551: buffer_init(&command);
1.1 deraadt 552:
1.33 markus 553: /*
554: * Save the command to execute on the remote host in a buffer. There
555: * is no limit on the length of the command, except by the maximum
556: * packet size. Also sets the tty flag if there is no command.
557: */
1.128 fgsch 558: if (!ac) {
1.31 markus 559: /* No command specified - execute shell on a tty. */
560: tty_flag = 1;
1.85 djm 561: if (subsystem_flag) {
1.128 fgsch 562: fprintf(stderr,
563: "You must specify a subsystem to invoke.\n");
1.85 djm 564: usage();
565: }
1.31 markus 566: } else {
1.128 fgsch 567: /* A command has been specified. Store it into the buffer. */
568: for (i = 0; i < ac; i++) {
569: if (i)
1.31 markus 570: buffer_append(&command, " ", 1);
571: buffer_append(&command, av[i], strlen(av[i]));
572: }
573: }
574:
575: /* Cannot fork to background if no command. */
1.63 markus 576: if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag)
1.31 markus 577: fatal("Cannot fork into background without a command to execute.");
578:
579: /* Allocate a tty by default if no command specified. */
580: if (buffer_len(&command) == 0)
581: tty_flag = 1;
582:
1.180 deraadt 583: /* Force no tty */
1.75 markus 584: if (no_tty_flag)
585: tty_flag = 0;
1.31 markus 586: /* Do not allocate a tty if stdin is not a tty. */
1.236 djm 587: if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
1.31 markus 588: if (tty_flag)
1.191 itojun 589: logit("Pseudo-terminal will not be allocated because stdin is not a terminal.");
1.31 markus 590: tty_flag = 0;
591: }
1.45 markus 592:
1.101 markus 593: /*
594: * Initialize "log" output. Since we are the client all output
595: * actually goes to stderr.
596: */
1.111 markus 597: log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
598: SYSLOG_FACILITY_USER, 1);
1.31 markus 599:
1.139 markus 600: /*
601: * Read per-user configuration file. Ignore the system wide config
602: * file if the user specifies a config file on the command line.
603: */
604: if (config != NULL) {
1.211 djm 605: if (!read_config_file(config, host, &options, 0))
1.142 stevesk 606: fatal("Can't open user config file %.100s: "
607: "%.100s", config, strerror(errno));
1.295 stevesk 608: } else {
1.139 markus 609: snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir,
610: _PATH_SSH_USER_CONFFILE);
1.210 djm 611: (void)read_config_file(buf, host, &options, 1);
1.139 markus 612:
1.145 markus 613: /* Read systemwide configuration file after use config. */
1.223 deraadt 614: (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
1.210 djm 615: &options, 0);
1.139 markus 616: }
1.31 markus 617:
618: /* Fill configuration defaults. */
619: fill_default_options(&options);
620:
1.196 djm 621: channel_set_af(options.address_family);
622:
1.31 markus 623: /* reinit */
1.101 markus 624: log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1);
1.31 markus 625:
626: if (options.user == NULL)
627: options.user = xstrdup(pw->pw_name);
628:
629: if (options.hostname != NULL)
630: host = options.hostname;
1.195 markus 631:
632: /* force lowercase for hostkey matching */
633: if (options.host_key_alias != NULL) {
634: for (p = options.host_key_alias; *p; p++)
635: if (isupper(*p))
1.271 deraadt 636: *p = (char)tolower(*p);
1.195 markus 637: }
1.190 markus 638:
1.246 djm 639: /* Get default port if port has not been set. */
640: if (options.port == 0) {
641: sp = getservbyname(SSH_SERVICE_NAME, "tcp");
642: options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
643: }
644:
1.190 markus 645: if (options.proxy_command != NULL &&
1.304 ! dtucker 646: strcmp(options.proxy_command, "none") == 0) {
! 647: xfree(options.proxy_command);
1.190 markus 648: options.proxy_command = NULL;
1.304 ! dtucker 649: }
1.245 djm 650: if (options.control_path != NULL &&
1.304 ! dtucker 651: strcmp(options.control_path, "none") == 0) {
! 652: xfree(options.control_path);
1.245 djm 653: options.control_path = NULL;
1.304 ! dtucker 654: }
1.31 markus 655:
1.214 djm 656: if (options.control_path != NULL) {
1.275 djm 657: char thishost[NI_MAXHOST];
1.261 djm 658:
1.275 djm 659: if (gethostname(thishost, sizeof(thishost)) == -1)
1.261 djm 660: fatal("gethostname: %s", strerror(errno));
1.241 djm 661: snprintf(buf, sizeof(buf), "%d", options.port);
662: cp = tilde_expand_filename(options.control_path,
663: original_real_uid);
1.304 ! dtucker 664: xfree(options.control_path);
1.241 djm 665: options.control_path = percent_expand(cp, "p", buf, "h", host,
1.275 djm 666: "r", options.user, "l", thishost, (char *)NULL);
1.241 djm 667: xfree(cp);
1.214 djm 668: }
1.240 djm 669: if (mux_command != 0 && options.control_path == NULL)
670: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 671: if (options.control_path != NULL)
1.237 jakob 672: control_client(options.control_path);
1.214 djm 673:
1.303 djm 674: timeout_ms = options.connection_timeout * 1000;
675:
1.77 markus 676: /* Open a connection to the remote host. */
1.203 djm 677: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 678: options.address_family, options.connection_attempts, &timeout_ms,
679: options.tcp_keep_alive,
1.177 markus 680: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 681: options.proxy_command) != 0)
1.257 dtucker 682: exit(255);
1.31 markus 683:
1.303 djm 684: if (timeout_ms > 0)
685: debug3("timeout: %d ms remain after connect", timeout_ms);
686:
1.33 markus 687: /*
688: * If we successfully made the connection, load the host private key
689: * in case we will need it later for combined rsa-rhosts
690: * authentication. This must be done before releasing extra
691: * privileges, because the file is only readable by root.
1.174 markus 692: * If we cannot access the private keys, load the public keys
693: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 694: */
1.112 markus 695: sensitive_data.nkeys = 0;
696: sensitive_data.keys = NULL;
1.173 markus 697: sensitive_data.external_keysign = 0;
1.178 markus 698: if (options.rhosts_rsa_authentication ||
699: options.hostbased_authentication) {
1.112 markus 700: sensitive_data.nkeys = 3;
1.274 deraadt 701: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 702: sizeof(Key));
1.177 markus 703:
704: PRIV_START;
1.112 markus 705: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 706: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.112 markus 707: sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
1.276 dtucker 708: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.112 markus 709: sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
1.276 dtucker 710: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 711: PRIV_END;
1.173 markus 712:
1.181 markus 713: if (options.hostbased_authentication == 1 &&
714: sensitive_data.keys[0] == NULL &&
1.173 markus 715: sensitive_data.keys[1] == NULL &&
716: sensitive_data.keys[2] == NULL) {
717: sensitive_data.keys[1] = key_load_public(
718: _PATH_HOST_DSA_KEY_FILE, NULL);
719: sensitive_data.keys[2] = key_load_public(
720: _PATH_HOST_RSA_KEY_FILE, NULL);
721: sensitive_data.external_keysign = 1;
722: }
1.31 markus 723: }
1.33 markus 724: /*
725: * Get rid of any extra privileges that we may have. We will no
726: * longer need them. Also, extra privileges could make it very hard
727: * to read identity files and other non-world-readable files from the
728: * user's home directory if it happens to be on a NFS volume where
729: * root is mapped to nobody.
730: */
1.225 dtucker 731: if (original_effective_uid == 0) {
732: PRIV_START;
733: permanently_set_uid(pw);
734: }
1.31 markus 735:
1.33 markus 736: /*
737: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 738: * directory if it doesn't already exist.
1.33 markus 739: */
1.138 jakob 740: snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1.31 markus 741: if (stat(buf, &st) < 0)
1.57 djm 742: if (mkdir(buf, 0700) < 0)
1.31 markus 743: error("Could not create directory '%.200s'.", buf);
744:
1.104 markus 745: /* load options.identity_files */
746: load_public_identity_files();
747:
748: /* Expand ~ in known host file names. */
749: /* XXX mem-leaks: */
1.72 markus 750: options.system_hostfile =
751: tilde_expand_filename(options.system_hostfile, original_real_uid);
752: options.user_hostfile =
753: tilde_expand_filename(options.user_hostfile, original_real_uid);
754: options.system_hostfile2 =
755: tilde_expand_filename(options.system_hostfile2, original_real_uid);
756: options.user_hostfile2 =
757: tilde_expand_filename(options.user_hostfile2, original_real_uid);
1.149 markus 758:
759: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.31 markus 760:
761: /* Log into the remote system. This never returns if the login fails. */
1.303 djm 762: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
763: pw, timeout_ms);
1.31 markus 764:
1.112 markus 765: /* We no longer need the private host keys. Clear them now. */
766: if (sensitive_data.nkeys != 0) {
767: for (i = 0; i < sensitive_data.nkeys; i++) {
768: if (sensitive_data.keys[i] != NULL) {
769: /* Destroys contents safely */
770: debug3("clear hostkey %d", i);
771: key_free(sensitive_data.keys[i]);
772: sensitive_data.keys[i] = NULL;
773: }
774: }
775: xfree(sensitive_data.keys);
1.134 markus 776: }
777: for (i = 0; i < options.num_identity_files; i++) {
778: if (options.identity_files[i]) {
779: xfree(options.identity_files[i]);
780: options.identity_files[i] = NULL;
781: }
782: if (options.identity_keys[i]) {
783: key_free(options.identity_keys[i]);
784: options.identity_keys[i] = NULL;
785: }
1.112 markus 786: }
1.31 markus 787:
1.45 markus 788: exit_status = compat20 ? ssh_session2() : ssh_session();
789: packet_close();
1.186 djm 790:
1.214 djm 791: if (options.control_path != NULL && control_fd != -1)
792: unlink(options.control_path);
793:
1.186 djm 794: /*
1.203 djm 795: * Send SIGHUP to proxy command if used. We don't wait() in
1.186 djm 796: * case it hangs and instead rely on init to reap the child
797: */
798: if (proxy_command_pid > 1)
799: kill(proxy_command_pid, SIGHUP);
800:
1.45 markus 801: return exit_status;
802: }
803:
1.126 itojun 804: static void
1.70 markus 805: ssh_init_forwarding(void)
806: {
1.86 markus 807: int success = 0;
1.70 markus 808: int i;
1.86 markus 809:
1.70 markus 810: /* Initiate local TCP/IP port forwardings. */
811: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 812: debug("Local connections to %.200s:%d forwarded to remote "
813: "address %.200s:%d",
1.234 deraadt 814: (options.local_forwards[i].listen_host == NULL) ?
815: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 816: options.local_forwards[i].listen_host,
817: options.local_forwards[i].listen_port,
818: options.local_forwards[i].connect_host,
819: options.local_forwards[i].connect_port);
1.158 markus 820: success += channel_setup_local_fwd_listener(
1.232 djm 821: options.local_forwards[i].listen_host,
822: options.local_forwards[i].listen_port,
823: options.local_forwards[i].connect_host,
824: options.local_forwards[i].connect_port,
1.70 markus 825: options.gateway_ports);
826: }
1.283 markus 827: if (i > 0 && success != i && options.exit_on_forward_failure)
828: fatal("Could not request local forwarding.");
1.86 markus 829: if (i > 0 && success == 0)
830: error("Could not request local forwarding.");
1.70 markus 831:
832: /* Initiate remote TCP/IP port forwardings. */
833: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 834: debug("Remote connections from %.200s:%d forwarded to "
835: "local address %.200s:%d",
1.248 djm 836: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 837: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 838: options.remote_forwards[i].listen_port,
839: options.remote_forwards[i].connect_host,
840: options.remote_forwards[i].connect_port);
1.283 markus 841: if (channel_request_remote_forwarding(
1.232 djm 842: options.remote_forwards[i].listen_host,
843: options.remote_forwards[i].listen_port,
844: options.remote_forwards[i].connect_host,
1.283 markus 845: options.remote_forwards[i].connect_port) < 0) {
846: if (options.exit_on_forward_failure)
847: fatal("Could not request remote forwarding.");
848: else
849: logit("Warning: Could not request remote "
850: "forwarding.");
851: }
1.70 markus 852: }
1.301 djm 853:
854: /* Initiate tunnel forwarding. */
855: if (options.tun_open != SSH_TUNMODE_NO) {
856: if (client_request_tun_fwd(options.tun_open,
857: options.tun_local, options.tun_remote) == -1) {
858: if (options.exit_on_forward_failure)
859: fatal("Could not request tunnel forwarding.");
860: else
861: error("Could not request tunnel forwarding.");
862: }
863: }
1.70 markus 864: }
865:
1.126 itojun 866: static void
1.70 markus 867: check_agent_present(void)
868: {
869: if (options.forward_agent) {
1.254 djm 870: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 871: if (!ssh_agent_present())
1.70 markus 872: options.forward_agent = 0;
873: }
874: }
875:
1.126 itojun 876: static int
1.45 markus 877: ssh_session(void)
878: {
879: int type;
880: int interactive = 0;
881: int have_tty = 0;
882: struct winsize ws;
883: char *cp;
1.243 djm 884: const char *display;
1.45 markus 885:
1.31 markus 886: /* Enable compression if requested. */
887: if (options.compression) {
888: debug("Requesting compression at level %d.", options.compression_level);
889:
890: if (options.compression_level < 1 || options.compression_level > 9)
891: fatal("Compression level must be from 1 (fast) to 9 (slow, best).");
892:
893: /* Send the request. */
894: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
895: packet_put_int(options.compression_level);
896: packet_send();
897: packet_write_wait();
1.156 markus 898: type = packet_read();
1.31 markus 899: if (type == SSH_SMSG_SUCCESS)
900: packet_start_compression(options.compression_level);
901: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 902: logit("Warning: Remote host refused compression.");
1.31 markus 903: else
904: packet_disconnect("Protocol error waiting for compression response.");
905: }
906: /* Allocate a pseudo tty if appropriate. */
907: if (tty_flag) {
908: debug("Requesting pty.");
909:
910: /* Start the packet. */
911: packet_start(SSH_CMSG_REQUEST_PTY);
912:
913: /* Store TERM in the packet. There is no limit on the
914: length of the string. */
915: cp = getenv("TERM");
916: if (!cp)
917: cp = "";
1.124 markus 918: packet_put_cstring(cp);
1.31 markus 919:
920: /* Store window size in the packet. */
921: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
922: memset(&ws, 0, sizeof(ws));
1.269 deraadt 923: packet_put_int((u_int)ws.ws_row);
924: packet_put_int((u_int)ws.ws_col);
925: packet_put_int((u_int)ws.ws_xpixel);
926: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 927:
928: /* Store tty modes in the packet. */
1.115 stevesk 929: tty_make_modes(fileno(stdin), NULL);
1.31 markus 930:
931: /* Send the packet, and wait for it to leave. */
932: packet_send();
933: packet_write_wait();
934:
935: /* Read response from the server. */
1.156 markus 936: type = packet_read();
1.43 markus 937: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 938: interactive = 1;
1.45 markus 939: have_tty = 1;
1.43 markus 940: } else if (type == SSH_SMSG_FAILURE)
1.191 itojun 941: logit("Warning: Remote host failed or refused to allocate a pseudo tty.");
1.31 markus 942: else
943: packet_disconnect("Protocol error waiting for pty request response.");
944: }
945: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 946: display = getenv("DISPLAY");
947: if (options.forward_x11 && display != NULL) {
1.150 stevesk 948: char *proto, *data;
1.50 markus 949: /* Get reasonable local authentication information. */
1.243 djm 950: client_x11_get_proto(display, options.xauth_location,
951: options.forward_x11_trusted, &proto, &data);
1.50 markus 952: /* Request forwarding with authentication spoofing. */
1.31 markus 953: debug("Requesting X11 forwarding with authentication spoofing.");
1.243 djm 954: x11_request_forwarding_with_spoofing(0, display, proto, data);
1.31 markus 955:
956: /* Read response from the server. */
1.156 markus 957: type = packet_read();
1.31 markus 958: if (type == SSH_SMSG_SUCCESS) {
959: interactive = 1;
1.50 markus 960: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 961: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 962: } else {
1.31 markus 963: packet_disconnect("Protocol error waiting for X11 forwarding");
1.50 markus 964: }
1.31 markus 965: }
966: /* Tell the packet module whether this is an interactive session. */
1.80 markus 967: packet_set_interactive(interactive);
1.31 markus 968:
969: /* Request authentication agent forwarding if appropriate. */
1.70 markus 970: check_agent_present();
971:
1.31 markus 972: if (options.forward_agent) {
973: debug("Requesting authentication agent forwarding.");
974: auth_request_forwarding();
975:
976: /* Read response from the server. */
1.156 markus 977: type = packet_read();
1.155 markus 978: packet_check_eom();
1.31 markus 979: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 980: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 981: }
982:
1.70 markus 983: /* Initiate port forwardings. */
984: ssh_init_forwarding();
1.34 markus 985:
986: /* If requested, let ssh continue in the background. */
1.48 markus 987: if (fork_after_authentication_flag)
1.34 markus 988: if (daemon(1, 1) < 0)
989: fatal("daemon() failed: %.200s", strerror(errno));
1.31 markus 990:
1.33 markus 991: /*
992: * If a command was specified on the command line, execute the
993: * command now. Otherwise request the server to start a shell.
994: */
1.31 markus 995: if (buffer_len(&command) > 0) {
996: int len = buffer_len(&command);
997: if (len > 900)
998: len = 900;
1.152 stevesk 999: debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command));
1.31 markus 1000: packet_start(SSH_CMSG_EXEC_CMD);
1001: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1002: packet_send();
1003: packet_write_wait();
1004: } else {
1005: debug("Requesting shell.");
1006: packet_start(SSH_CMSG_EXEC_SHELL);
1007: packet_send();
1008: packet_write_wait();
1009: }
1010:
1011: /* Enter the interactive session. */
1.119 stevesk 1012: return client_loop(have_tty, tty_flag ?
1013: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.45 markus 1014: }
1015:
1.126 itojun 1016: static void
1.214 djm 1017: ssh_subsystem_reply(int type, u_int32_t seq, void *ctxt)
1.89 markus 1018: {
1019: int id, len;
1020:
1021: id = packet_get_int();
1022: len = buffer_len(&command);
1.100 markus 1023: if (len > 900)
1024: len = 900;
1.155 markus 1025: packet_check_eom();
1.89 markus 1026: if (type == SSH2_MSG_CHANNEL_FAILURE)
1027: fatal("Request for subsystem '%.*s' failed on channel %d",
1.152 stevesk 1028: len, (u_char *)buffer_ptr(&command), id);
1.170 markus 1029: }
1030:
1031: void
1.206 markus 1032: client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt)
1.170 markus 1033: {
1034: int i;
1035:
1036: i = client_global_request_id++;
1.206 markus 1037: if (i >= options.num_remote_forwards)
1.170 markus 1038: return;
1039: debug("remote forward %s for: listen %d, connect %s:%d",
1040: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1.232 djm 1041: options.remote_forwards[i].listen_port,
1042: options.remote_forwards[i].connect_host,
1043: options.remote_forwards[i].connect_port);
1.283 markus 1044: if (type == SSH2_MSG_REQUEST_FAILURE) {
1045: if (options.exit_on_forward_failure)
1046: fatal("Error: remote port forwarding failed for "
1047: "listen port %d",
1048: options.remote_forwards[i].listen_port);
1049: else
1050: logit("Warning: remote port forwarding failed for "
1051: "listen port %d",
1052: options.remote_forwards[i].listen_port);
1053: }
1.89 markus 1054: }
1055:
1.126 itojun 1056: static void
1.214 djm 1057: ssh_control_listener(void)
1.45 markus 1058: {
1.214 djm 1059: struct sockaddr_un addr;
1060: mode_t old_umask;
1.223 deraadt 1061:
1.242 djm 1062: if (options.control_path == NULL ||
1063: options.control_master == SSHCTL_MASTER_NO)
1.214 djm 1064: return;
1065:
1.242 djm 1066: debug("setting up multiplex master socket");
1067:
1.214 djm 1068: memset(&addr, '\0', sizeof(addr));
1069: addr.sun_family = AF_UNIX;
1070: addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
1071: strlen(options.control_path) + 1;
1072:
1073: if (strlcpy(addr.sun_path, options.control_path,
1074: sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
1075: fatal("ControlPath too long");
1076:
1077: if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
1.252 stevesk 1078: fatal("%s socket(): %s", __func__, strerror(errno));
1.214 djm 1079:
1080: old_umask = umask(0177);
1.270 deraadt 1081: if (bind(control_fd, (struct sockaddr *)&addr, addr.sun_len) == -1) {
1.214 djm 1082: control_fd = -1;
1.238 djm 1083: if (errno == EINVAL || errno == EADDRINUSE)
1.214 djm 1084: fatal("ControlSocket %s already exists",
1085: options.control_path);
1086: else
1.252 stevesk 1087: fatal("%s bind(): %s", __func__, strerror(errno));
1.214 djm 1088: }
1089: umask(old_umask);
1.80 markus 1090:
1.214 djm 1091: if (listen(control_fd, 64) == -1)
1.252 stevesk 1092: fatal("%s listen(): %s", __func__, strerror(errno));
1.31 markus 1093:
1.214 djm 1094: set_nonblock(control_fd);
1095: }
1.45 markus 1096:
1.214 djm 1097: /* request pty/x11/agent/tcpfwd/shell for channel */
1098: static void
1099: ssh_session2_setup(int id, void *arg)
1100: {
1.215 djm 1101: extern char **environ;
1.243 djm 1102: const char *display;
1103: int interactive = tty_flag;
1.215 djm 1104:
1.248 djm 1105: display = getenv("DISPLAY");
1.243 djm 1106: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1107: char *proto, *data;
1.50 markus 1108: /* Get reasonable local authentication information. */
1.243 djm 1109: client_x11_get_proto(display, options.xauth_location,
1110: options.forward_x11_trusted, &proto, &data);
1.50 markus 1111: /* Request forwarding with authentication spoofing. */
1112: debug("Requesting X11 forwarding with authentication spoofing.");
1.243 djm 1113: x11_request_forwarding_with_spoofing(id, display, proto, data);
1.80 markus 1114: interactive = 1;
1.50 markus 1115: /* XXX wait for reply */
1116: }
1117:
1.70 markus 1118: check_agent_present();
1119: if (options.forward_agent) {
1120: debug("Requesting authentication agent forwarding.");
1121: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1122: packet_send();
1.212 djm 1123: }
1124:
1.214 djm 1125: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.215 djm 1126: NULL, fileno(stdin), &command, environ, &ssh_subsystem_reply);
1.90 markus 1127:
1.80 markus 1128: packet_set_interactive(interactive);
1.45 markus 1129: }
1130:
1.143 markus 1131: /* open new channel for a session */
1.126 itojun 1132: static int
1.143 markus 1133: ssh_session2_open(void)
1.45 markus 1134: {
1.118 markus 1135: Channel *c;
1136: int window, packetmax, in, out, err;
1.60 markus 1137:
1.62 markus 1138: if (stdin_null_flag) {
1.93 itojun 1139: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1140: } else {
1141: in = dup(STDIN_FILENO);
1142: }
1.60 markus 1143: out = dup(STDOUT_FILENO);
1144: err = dup(STDERR_FILENO);
1.45 markus 1145:
1146: if (in < 0 || out < 0 || err < 0)
1.62 markus 1147: fatal("dup() in/out/err failed");
1.45 markus 1148:
1.69 markus 1149: /* enable nonblocking unless tty */
1150: if (!isatty(in))
1151: set_nonblock(in);
1152: if (!isatty(out))
1153: set_nonblock(out);
1154: if (!isatty(err))
1155: set_nonblock(err);
1156:
1.65 markus 1157: window = CHAN_SES_WINDOW_DEFAULT;
1158: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1159: if (tty_flag) {
1160: window >>= 1;
1161: packetmax >>= 1;
1.45 markus 1162: }
1.118 markus 1163: c = channel_new(
1.45 markus 1164: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1165: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1166: "client-session", /*nonblock*/0);
1.45 markus 1167:
1.143 markus 1168: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1169:
1.122 markus 1170: channel_send_open(c->self);
1.143 markus 1171: if (!no_shell_flag)
1.214 djm 1172: channel_register_confirm(c->self, ssh_session2_setup, NULL);
1.106 markus 1173:
1.118 markus 1174: return c->self;
1.106 markus 1175: }
1176:
1.126 itojun 1177: static int
1.106 markus 1178: ssh_session2(void)
1179: {
1.143 markus 1180: int id = -1;
1.106 markus 1181:
1182: /* XXX should be pre-session */
1183: ssh_init_forwarding();
1184:
1.143 markus 1185: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1186: id = ssh_session2_open();
1.255 reyk 1187:
1188: /* Execute a local command */
1189: if (options.local_command != NULL &&
1190: options.permit_local_command)
1191: ssh_local_cmd(options.local_command);
1.301 djm 1192:
1193: /* Start listening for multiplex clients */
1194: ssh_control_listener();
1.106 markus 1195:
1196: /* If requested, let ssh continue in the background. */
1197: if (fork_after_authentication_flag)
1198: if (daemon(1, 1) < 0)
1199: fatal("daemon() failed: %.200s", strerror(errno));
1.31 markus 1200:
1.119 stevesk 1201: return client_loop(tty_flag, tty_flag ?
1202: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1203: }
1204:
1.126 itojun 1205: static void
1.104 markus 1206: load_public_identity_files(void)
1207: {
1.275 djm 1208: char *filename, *cp, thishost[NI_MAXHOST];
1.167 markus 1209: int i = 0;
1.104 markus 1210: Key *public;
1.275 djm 1211: struct passwd *pw;
1.167 markus 1212: #ifdef SMARTCARD
1213: Key **keys;
1.104 markus 1214:
1.133 markus 1215: if (options.smartcard_device != NULL &&
1.167 markus 1216: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.292 stevesk 1217: (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL) {
1.167 markus 1218: int count = 0;
1219: for (i = 0; keys[i] != NULL; i++) {
1220: count++;
1221: memmove(&options.identity_files[1], &options.identity_files[0],
1222: sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1));
1223: memmove(&options.identity_keys[1], &options.identity_keys[0],
1224: sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1));
1225: options.num_identity_files++;
1226: options.identity_keys[0] = keys[i];
1.194 markus 1227: options.identity_files[0] = sc_get_key_label(keys[i]);
1.167 markus 1228: }
1.168 markus 1229: if (options.num_identity_files > SSH_MAX_IDENTITY_FILES)
1230: options.num_identity_files = SSH_MAX_IDENTITY_FILES;
1.167 markus 1231: i = count;
1232: xfree(keys);
1.127 markus 1233: }
1.136 jakob 1234: #endif /* SMARTCARD */
1.275 djm 1235: if ((pw = getpwuid(original_real_uid)) == NULL)
1236: fatal("load_public_identity_files: getpwuid failed");
1237: if (gethostname(thishost, sizeof(thishost)) == -1)
1238: fatal("load_public_identity_files: gethostname: %s",
1239: strerror(errno));
1.131 millert 1240: for (; i < options.num_identity_files; i++) {
1.275 djm 1241: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1242: original_real_uid);
1.275 djm 1243: filename = percent_expand(cp, "d", pw->pw_dir,
1.293 deraadt 1244: "u", pw->pw_name, "l", thishost, "h", host,
1.275 djm 1245: "r", options.user, (char *)NULL);
1246: xfree(cp);
1.131 millert 1247: public = key_load_public(filename, NULL);
1248: debug("identity file %s type %d", filename,
1249: public ? public->type : -1);
1250: xfree(options.identity_files[i]);
1251: options.identity_files[i] = filename;
1252: options.identity_keys[i] = public;
1253: }
1.214 djm 1254: }
1255:
1256: static void
1257: control_client_sighandler(int signo)
1258: {
1259: control_client_terminate = signo;
1260: }
1261:
1262: static void
1263: control_client_sigrelay(int signo)
1264: {
1265: if (control_server_pid > 1)
1266: kill(control_server_pid, signo);
1267: }
1268:
1.220 djm 1269: static int
1270: env_permitted(char *env)
1271: {
1.282 dtucker 1272: int i, ret;
1.220 djm 1273: char name[1024], *cp;
1274:
1.282 dtucker 1275: if ((cp = strchr(env, '=')) == NULL || cp == env)
1.220 djm 1276: return (0);
1.284 stevesk 1277: ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
1.282 dtucker 1278: if (ret <= 0 || (size_t)ret >= sizeof(name))
1279: fatal("env_permitted: name '%.100s...' too long", env);
1.220 djm 1280:
1281: for (i = 0; i < options.num_send_env; i++)
1282: if (match_pattern(name, options.send_env[i]))
1283: return (1);
1284:
1285: return (0);
1286: }
1287:
1.214 djm 1288: static void
1289: control_client(const char *path)
1290: {
1291: struct sockaddr_un addr;
1.300 djm 1292: int i, r, fd, sock, exitval[2], num_env;
1.214 djm 1293: Buffer m;
1.229 djm 1294: char *term;
1.215 djm 1295: extern char **environ;
1.229 djm 1296: u_int flags;
1.242 djm 1297:
1298: if (mux_command == 0)
1299: mux_command = SSHMUX_COMMAND_OPEN;
1300:
1301: switch (options.control_master) {
1302: case SSHCTL_MASTER_AUTO:
1303: case SSHCTL_MASTER_AUTO_ASK:
1304: debug("auto-mux: Trying existing master");
1305: /* FALLTHROUGH */
1306: case SSHCTL_MASTER_NO:
1307: break;
1308: default:
1309: return;
1310: }
1.228 djm 1311:
1.214 djm 1312: memset(&addr, '\0', sizeof(addr));
1313: addr.sun_family = AF_UNIX;
1314: addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
1315: strlen(path) + 1;
1316:
1317: if (strlcpy(addr.sun_path, path,
1318: sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
1319: fatal("ControlPath too long");
1320:
1321: if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
1322: fatal("%s socket(): %s", __func__, strerror(errno));
1323:
1.270 deraadt 1324: if (connect(sock, (struct sockaddr *)&addr, addr.sun_len) == -1) {
1.240 djm 1325: if (mux_command != SSHMUX_COMMAND_OPEN) {
1326: fatal("Control socket connect(%.100s): %s", path,
1327: strerror(errno));
1328: }
1.239 djm 1329: if (errno == ENOENT)
1.268 deraadt 1330: debug("Control socket \"%.100s\" does not exist", path);
1.239 djm 1331: else {
1.268 deraadt 1332: error("Control socket connect(%.100s): %s", path,
1.239 djm 1333: strerror(errno));
1334: }
1.268 deraadt 1335: close(sock);
1336: return;
1337: }
1.248 djm 1338:
1.268 deraadt 1339: if (stdin_null_flag) {
1340: if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
1341: fatal("open(/dev/null): %s", strerror(errno));
1342: if (dup2(fd, STDIN_FILENO) == -1)
1343: fatal("dup2: %s", strerror(errno));
1344: if (fd > STDERR_FILENO)
1345: close(fd);
1346: }
1.248 djm 1347:
1.247 djm 1348: term = getenv("TERM");
1.229 djm 1349:
1350: flags = 0;
1351: if (tty_flag)
1352: flags |= SSHMUX_FLAG_TTY;
1353: if (subsystem_flag)
1354: flags |= SSHMUX_FLAG_SUBSYS;
1.247 djm 1355: if (options.forward_x11)
1356: flags |= SSHMUX_FLAG_X11_FWD;
1357: if (options.forward_agent)
1358: flags |= SSHMUX_FLAG_AGENT_FWD;
1.214 djm 1359:
1360: buffer_init(&m);
1361:
1.229 djm 1362: /* Send our command to server */
1363: buffer_put_int(&m, mux_command);
1364: buffer_put_int(&m, flags);
1.247 djm 1365: if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
1.229 djm 1366: fatal("%s: msg_send", __func__);
1367: buffer_clear(&m);
1368:
1369: /* Get authorisation status and PID of controlee */
1.214 djm 1370: if (ssh_msg_recv(sock, &m) == -1)
1371: fatal("%s: msg_recv", __func__);
1.247 djm 1372: if (buffer_get_char(&m) != SSHMUX_VER)
1.214 djm 1373: fatal("%s: wrong version", __func__);
1.216 djm 1374: if (buffer_get_int(&m) != 1)
1375: fatal("Connection to master denied");
1.214 djm 1376: control_server_pid = buffer_get_int(&m);
1377:
1378: buffer_clear(&m);
1379:
1.229 djm 1380: switch (mux_command) {
1381: case SSHMUX_COMMAND_ALIVE_CHECK:
1.234 deraadt 1382: fprintf(stderr, "Master running (pid=%d)\r\n",
1.229 djm 1383: control_server_pid);
1384: exit(0);
1385: case SSHMUX_COMMAND_TERMINATE:
1386: fprintf(stderr, "Exit request sent.\r\n");
1387: exit(0);
1388: case SSHMUX_COMMAND_OPEN:
1389: /* continue below */
1390: break;
1391: default:
1392: fatal("silly mux_command %d", mux_command);
1393: }
1394:
1395: /* SSHMUX_COMMAND_OPEN */
1.247 djm 1396: buffer_put_cstring(&m, term ? term : "");
1.214 djm 1397: buffer_append(&command, "\0", 1);
1398: buffer_put_cstring(&m, buffer_ptr(&command));
1.215 djm 1399:
1.220 djm 1400: if (options.num_send_env == 0 || environ == NULL) {
1401: buffer_put_int(&m, 0);
1.223 deraadt 1402: } else {
1.220 djm 1403: /* Pass environment */
1404: num_env = 0;
1405: for (i = 0; environ[i] != NULL; i++)
1406: if (env_permitted(environ[i]))
1407: num_env++; /* Count */
1.223 deraadt 1408:
1.220 djm 1409: buffer_put_int(&m, num_env);
1410:
1.222 dtucker 1411: for (i = 0; environ[i] != NULL && num_env >= 0; i++)
1412: if (env_permitted(environ[i])) {
1413: num_env--;
1.220 djm 1414: buffer_put_cstring(&m, environ[i]);
1.222 dtucker 1415: }
1.220 djm 1416: }
1.214 djm 1417:
1.247 djm 1418: if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
1.214 djm 1419: fatal("%s: msg_send", __func__);
1420:
1.302 djm 1421: if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
1422: mm_send_fd(sock, STDOUT_FILENO) == -1 ||
1423: mm_send_fd(sock, STDERR_FILENO) == -1)
1424: fatal("%s: send fds failed", __func__);
1.214 djm 1425:
1426: /* Wait for reply, so master has a chance to gather ttymodes */
1427: buffer_clear(&m);
1428: if (ssh_msg_recv(sock, &m) == -1)
1429: fatal("%s: msg_recv", __func__);
1.247 djm 1430: if (buffer_get_char(&m) != SSHMUX_VER)
1.229 djm 1431: fatal("%s: wrong version", __func__);
1.214 djm 1432: buffer_free(&m);
1.218 djm 1433:
1.226 djm 1434: signal(SIGHUP, control_client_sighandler);
1.218 djm 1435: signal(SIGINT, control_client_sighandler);
1436: signal(SIGTERM, control_client_sighandler);
1437: signal(SIGWINCH, control_client_sigrelay);
1.214 djm 1438:
1439: if (tty_flag)
1440: enter_raw_mode();
1441:
1.300 djm 1442: /*
1443: * Stick around until the controlee closes the client_fd.
1444: * Before it does, it is expected to write this process' exit
1445: * value (one int). This process must read the value and wait for
1446: * the closure of the client_fd; if this one closes early, the
1447: * multiplex master will terminate early too (possibly losing data).
1448: */
1449: exitval[0] = 0;
1.296 djm 1450: for (i = 0; !control_client_terminate && i < (int)sizeof(exitval);) {
1.300 djm 1451: r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
1.214 djm 1452: if (r == 0) {
1453: debug2("Received EOF from master");
1454: break;
1455: }
1.299 djm 1456: if (r == -1) {
1457: if (errno == EINTR)
1458: continue;
1.214 djm 1459: fatal("%s: read %s", __func__, strerror(errno));
1.299 djm 1460: }
1.296 djm 1461: i += r;
1.214 djm 1462: }
1.300 djm 1463:
1.296 djm 1464: close(sock);
1465: leave_raw_mode();
1.300 djm 1466: if (i > (int)sizeof(int))
1467: fatal("%s: master returned too much data (%d > %lu)",
1468: __func__, i, sizeof(int));
1.296 djm 1469: if (control_client_terminate) {
1.214 djm 1470: debug2("Exiting on signal %d", control_client_terminate);
1.300 djm 1471: exitval[0] = 255;
1472: } else if (i < (int)sizeof(int)) {
1.296 djm 1473: debug2("Control master terminated unexpectedly");
1.300 djm 1474: exitval[0] = 255;
1.296 djm 1475: } else
1.300 djm 1476: debug2("Received exit status from master %d", exitval[0]);
1.214 djm 1477:
1478: if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
1.300 djm 1479: fprintf(stderr, "Shared connection to %s closed.\r\n", host);
1.214 djm 1480:
1.300 djm 1481: exit(exitval[0]);
1.1 deraadt 1482: }
![[BACK]](/icons/back.gif){kind=icon}
Return to ssh.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh