1 /* 2 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * All rights reserved 5 * Ssh client program. This program can be used to log into a remote machine. 6 * The software supports strong authentication, encryption, and forwarding 7 * of X11, TCP/IP, and authentication connections. 8 * 9 * As far as I am concerned, the code I have written for this software 10 * can be used freely for any purpose. Any derived versions of this 11 * software must be clearly marked as such, and if the derived work is 12 * incompatible with the protocol description in the RFC file, it must be 13 * called by a name other than "ssh" or "Secure Shell". 14 * 15 * Copyright (c) 1999 Niels Provos. All rights reserved. 16 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. 17 * 18 * Modified to work with SSL by Niels Provos <provos@citi.umich.edu> 19 * in Canada (German citizen). 20 * 21 * Redistribution and use in source and binary forms, with or without 22 * modification, are permitted provided that the following conditions 23 * are met: 24 * 1. Redistributions of source code must retain the above copyright 25 * notice, this list of conditions and the following disclaimer. 26 * 2. Redistributions in binary form must reproduce the above copyright 27 * notice, this list of conditions and the following disclaimer in the 28 * documentation and/or other materials provided with the distribution. 29 * 30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 40 */ 41 42 #include "includes.h" 43 RCSID("$OpenBSD: ssh.c,v 1.257 2005/12/20 04:41:07 dtucker Exp $"); 44 RCSID("$FreeBSD$"); 45 46 #include <openssl/evp.h> 47 #include <openssl/err.h> 48 49 #include "ssh.h" 50 #include "ssh1.h" 51 #include "ssh2.h" 52 #include "compat.h" 53 #include "cipher.h" 54 #include "xmalloc.h" 55 #include "packet.h" 56 #include "buffer.h" 57 #include "bufaux.h" 58 #include "channels.h" 59 #include "key.h" 60 #include "authfd.h" 61 #include "authfile.h" 62 #include "pathnames.h" 63 #include "dispatch.h" 64 #include "clientloop.h" 65 #include "log.h" 66 #include "readconf.h" 67 #include "sshconnect.h" 68 #include "misc.h" 69 #include "kex.h" 70 #include "mac.h" 71 #include "sshpty.h" 72 #include "match.h" 73 #include "msg.h" 74 #include "monitor_fdpass.h" 75 #include "uidswap.h" 76 77 #ifdef SMARTCARD 78 #include "scard.h" 79 #endif 80 81 extern char *__progname; 82 83 /* Flag indicating whether debug mode is on. This can be set on the command line. */ 84 int debug_flag = 0; 85 86 /* Flag indicating whether a tty should be allocated */ 87 int tty_flag = 0; 88 int no_tty_flag = 0; 89 int force_tty_flag = 0; 90 91 /* don't exec a shell */ 92 int no_shell_flag = 0; 93 94 /* 95 * Flag indicating that nothing should be read from stdin. This can be set 96 * on the command line. 97 */ 98 int stdin_null_flag = 0; 99 100 /* 101 * Flag indicating that ssh should fork after authentication. This is useful 102 * so that the passphrase can be entered manually, and then ssh goes to the 103 * background. 104 */ 105 int fork_after_authentication_flag = 0; 106 107 /* 108 * General data structure for command line options and options configurable 109 * in configuration files. See readconf.h. 110 */ 111 Options options; 112 113 /* optional user configfile */ 114 char *config = NULL; 115 116 /* 117 * Name of the host we are connecting to. This is the name given on the 118 * command line, or the HostName specified for the user-supplied name in a 119 * configuration file. 120 */ 121 char *host; 122 123 /* socket address the host resolves to */ 124 struct sockaddr_storage hostaddr; 125 126 /* Private host keys. */ 127 Sensitive sensitive_data; 128 129 /* Original real UID. */ 130 uid_t original_real_uid; 131 uid_t original_effective_uid; 132 133 /* command to be executed */ 134 Buffer command; 135 136 /* Should we execute a command or invoke a subsystem? */ 137 int subsystem_flag = 0; 138 139 /* # of replies received for global requests */ 140 static int client_global_request_id = 0; 141 142 /* pid of proxycommand child process */ 143 pid_t proxy_command_pid = 0; 144 145 /* fd to control socket */ 146 int control_fd = -1; 147 148 /* Multiplexing control command */ 149 static u_int mux_command = 0; 150 151 /* Only used in control client mode */ 152 volatile sig_atomic_t control_client_terminate = 0; 153 u_int control_server_pid = 0; 154 155 /* Prints a help message to the user. This function never returns. */ 156 157 static void 158 usage(void) 159 { 160 fprintf(stderr, 161 "usage: ssh [-1246AaCfgkMNnqsTtVvXxY] [-b bind_address] [-c cipher_spec]\n" 162 " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n" 163 " [-i identity_file] [-L [bind_address:]port:host:hostport]\n" 164 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" 165 " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" 166 " [-w tunnel:tunnel] [user@]hostname [command]\n" 167 ); 168 exit(255); 169 } 170 171 static int ssh_session(void); 172 static int ssh_session2(void); 173 static void load_public_identity_files(void); 174 static void control_client(const char *path); 175 176 /* 177 * Main program for the ssh client. 178 */ 179 int 180 main(int ac, char **av) 181 { 182 int i, opt, exit_status; 183 char *p, *cp, *line, buf[256]; 184 struct stat st; 185 struct passwd *pw; 186 int dummy; 187 extern int optind, optreset; 188 extern char *optarg; 189 struct servent *sp; 190 Forward fwd; 191 192 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 193 sanitise_stdfd(); 194 195 __progname = ssh_get_progname(av[0]); 196 init_rng(); 197 198 /* 199 * Save the original real uid. It will be needed later (uid-swapping 200 * may clobber the real uid). 201 */ 202 original_real_uid = getuid(); 203 original_effective_uid = geteuid(); 204 205 /* 206 * Use uid-swapping to give up root privileges for the duration of 207 * option processing. We will re-instantiate the rights when we are 208 * ready to create the privileged port, and will permanently drop 209 * them when the port has been created (actually, when the connection 210 * has been made, as we may need to create the port several times). 211 */ 212 PRIV_END; 213 214 #ifdef HAVE_SETRLIMIT 215 /* If we are installed setuid root be careful to not drop core. */ 216 if (original_real_uid != original_effective_uid) { 217 struct rlimit rlim; 218 rlim.rlim_cur = rlim.rlim_max = 0; 219 if (setrlimit(RLIMIT_CORE, &rlim) < 0) 220 fatal("setrlimit failed: %.100s", strerror(errno)); 221 } 222 #endif 223 /* Get user data. */ 224 pw = getpwuid(original_real_uid); 225 if (!pw) { 226 logit("You don't exist, go away!"); 227 exit(255); 228 } 229 /* Take a copy of the returned structure. */ 230 pw = pwcopy(pw); 231 232 /* 233 * Set our umask to something reasonable, as some files are created 234 * with the default umask. This will make them world-readable but 235 * writable only by the owner, which is ok for all files for which we 236 * don't set the modes explicitly. 237 */ 238 umask(022); 239 240 /* Initialize option structure to indicate that no values have been set. */ 241 initialize_options(&options); 242 243 /* Parse command-line arguments. */ 244 host = NULL; 245 246 again: 247 while ((opt = getopt(ac, av, 248 "1246ab:c:e:fgi:kl:m:no:p:qstvxACD:F:I:L:MNO:PR:S:TVw:XY")) != -1) { 249 switch (opt) { 250 case '1': 251 options.protocol = SSH_PROTO_1; 252 break; 253 case '2': 254 options.protocol = SSH_PROTO_2; 255 break; 256 case '4': 257 options.address_family = AF_INET; 258 break; 259 case '6': 260 options.address_family = AF_INET6; 261 break; 262 case 'n': 263 stdin_null_flag = 1; 264 break; 265 case 'f': 266 fork_after_authentication_flag = 1; 267 stdin_null_flag = 1; 268 break; 269 case 'x': 270 options.forward_x11 = 0; 271 break; 272 case 'X': 273 options.forward_x11 = 1; 274 break; 275 case 'Y': 276 options.forward_x11 = 1; 277 options.forward_x11_trusted = 1; 278 break; 279 case 'g': 280 options.gateway_ports = 1; 281 break; 282 case 'O': 283 if (strcmp(optarg, "check") == 0) 284 mux_command = SSHMUX_COMMAND_ALIVE_CHECK; 285 else if (strcmp(optarg, "exit") == 0) 286 mux_command = SSHMUX_COMMAND_TERMINATE; 287 else 288 fatal("Invalid multiplex command."); 289 break; 290 case 'P': /* deprecated */ 291 options.use_privileged_port = 0; 292 break; 293 case 'a': 294 options.forward_agent = 0; 295 break; 296 case 'A': 297 options.forward_agent = 1; 298 break; 299 case 'k': 300 options.gss_deleg_creds = 0; 301 break; 302 case 'i': 303 if (stat(optarg, &st) < 0) { 304 fprintf(stderr, "Warning: Identity file %s " 305 "not accessible: %s.\n", optarg, 306 strerror(errno)); 307 break; 308 } 309 if (options.num_identity_files >= 310 SSH_MAX_IDENTITY_FILES) 311 fatal("Too many identity files specified " 312 "(max %d)", SSH_MAX_IDENTITY_FILES); 313 options.identity_files[options.num_identity_files++] = 314 xstrdup(optarg); 315 break; 316 case 'I': 317 #ifdef SMARTCARD 318 options.smartcard_device = xstrdup(optarg); 319 #else 320 fprintf(stderr, "no support for smartcards.\n"); 321 #endif 322 break; 323 case 't': 324 if (tty_flag) 325 force_tty_flag = 1; 326 tty_flag = 1; 327 break; 328 case 'v': 329 if (debug_flag == 0) { 330 debug_flag = 1; 331 options.log_level = SYSLOG_LEVEL_DEBUG1; 332 } else { 333 if (options.log_level < SYSLOG_LEVEL_DEBUG3) 334 options.log_level++; 335 break; 336 } 337 /* FALLTHROUGH */ 338 case 'V': 339 fprintf(stderr, "%s, %s\n", 340 SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); 341 if (opt == 'V') 342 exit(0); 343 break; 344 case 'w': 345 if (options.tun_open == -1) 346 options.tun_open = SSH_TUNMODE_DEFAULT; 347 options.tun_local = a2tun(optarg, &options.tun_remote); 348 if (options.tun_local == SSH_TUNID_ERR) { 349 fprintf(stderr, "Bad tun device '%s'\n", optarg); 350 exit(255); 351 } 352 break; 353 case 'q': 354 options.log_level = SYSLOG_LEVEL_QUIET; 355 break; 356 case 'e': 357 if (optarg[0] == '^' && optarg[2] == 0 && 358 (u_char) optarg[1] >= 64 && 359 (u_char) optarg[1] < 128) 360 options.escape_char = (u_char) optarg[1] & 31; 361 else if (strlen(optarg) == 1) 362 options.escape_char = (u_char) optarg[0]; 363 else if (strcmp(optarg, "none") == 0) 364 options.escape_char = SSH_ESCAPECHAR_NONE; 365 else { 366 fprintf(stderr, "Bad escape character '%s'.\n", 367 optarg); 368 exit(255); 369 } 370 break; 371 case 'c': 372 if (ciphers_valid(optarg)) { 373 /* SSH2 only */ 374 options.ciphers = xstrdup(optarg); 375 options.cipher = SSH_CIPHER_INVALID; 376 } else { 377 /* SSH1 only */ 378 options.cipher = cipher_number(optarg); 379 if (options.cipher == -1) { 380 fprintf(stderr, 381 "Unknown cipher type '%s'\n", 382 optarg); 383 exit(255); 384 } 385 if (options.cipher == SSH_CIPHER_3DES) 386 options.ciphers = "3des-cbc"; 387 else if (options.cipher == SSH_CIPHER_BLOWFISH) 388 options.ciphers = "blowfish-cbc"; 389 else 390 options.ciphers = (char *)-1; 391 } 392 break; 393 case 'm': 394 if (mac_valid(optarg)) 395 options.macs = xstrdup(optarg); 396 else { 397 fprintf(stderr, "Unknown mac type '%s'\n", 398 optarg); 399 exit(255); 400 } 401 break; 402 case 'M': 403 if (options.control_master == SSHCTL_MASTER_YES) 404 options.control_master = SSHCTL_MASTER_ASK; 405 else 406 options.control_master = SSHCTL_MASTER_YES; 407 break; 408 case 'p': 409 options.port = a2port(optarg); 410 if (options.port == 0) { 411 fprintf(stderr, "Bad port '%s'\n", optarg); 412 exit(255); 413 } 414 break; 415 case 'l': 416 options.user = optarg; 417 break; 418 419 case 'L': 420 if (parse_forward(&fwd, optarg)) 421 add_local_forward(&options, &fwd); 422 else { 423 fprintf(stderr, 424 "Bad local forwarding specification '%s'\n", 425 optarg); 426 exit(255); 427 } 428 break; 429 430 case 'R': 431 if (parse_forward(&fwd, optarg)) { 432 add_remote_forward(&options, &fwd); 433 } else { 434 fprintf(stderr, 435 "Bad remote forwarding specification " 436 "'%s'\n", optarg); 437 exit(255); 438 } 439 break; 440 441 case 'D': 442 cp = p = xstrdup(optarg); 443 memset(&fwd, '\0', sizeof(fwd)); 444 fwd.connect_host = "socks"; 445 if ((fwd.listen_host = hpdelim(&cp)) == NULL) { 446 fprintf(stderr, "Bad dynamic forwarding " 447 "specification '%.100s'\n", optarg); 448 exit(255); 449 } 450 if (cp != NULL) { 451 fwd.listen_port = a2port(cp); 452 fwd.listen_host = cleanhostname(fwd.listen_host); 453 } else { 454 fwd.listen_port = a2port(fwd.listen_host); 455 fwd.listen_host = NULL; 456 } 457 458 if (fwd.listen_port == 0) { 459 fprintf(stderr, "Bad dynamic port '%s'\n", 460 optarg); 461 exit(255); 462 } 463 add_local_forward(&options, &fwd); 464 xfree(p); 465 break; 466 467 case 'C': 468 options.compression = 1; 469 break; 470 case 'N': 471 no_shell_flag = 1; 472 no_tty_flag = 1; 473 break; 474 case 'T': 475 no_tty_flag = 1; 476 break; 477 case 'o': 478 dummy = 1; 479 line = xstrdup(optarg); 480 if (process_config_line(&options, host ? host : "", 481 line, "command-line", 0, &dummy) != 0) 482 exit(255); 483 xfree(line); 484 break; 485 case 's': 486 subsystem_flag = 1; 487 break; 488 case 'S': 489 if (options.control_path != NULL) 490 free(options.control_path); 491 options.control_path = xstrdup(optarg); 492 break; 493 case 'b': 494 options.bind_address = optarg; 495 break; 496 case 'F': 497 config = optarg; 498 break; 499 default: 500 usage(); 501 } 502 } 503 504 ac -= optind; 505 av += optind; 506 507 if (ac > 0 && !host && **av != '-') { 508 if (strrchr(*av, '@')) { 509 p = xstrdup(*av); 510 cp = strrchr(p, '@'); 511 if (cp == NULL || cp == p) 512 usage(); 513 options.user = p; 514 *cp = '\0'; 515 host = ++cp; 516 } else 517 host = *av; 518 if (ac > 1) { 519 optind = optreset = 1; 520 goto again; 521 } 522 ac--, av++; 523 } 524 525 /* Check that we got a host name. */ 526 if (!host) 527 usage(); 528 529 SSLeay_add_all_algorithms(); 530 ERR_load_crypto_strings(); 531 532 /* Initialize the command to execute on remote host. */ 533 buffer_init(&command); 534 535 /* 536 * Save the command to execute on the remote host in a buffer. There 537 * is no limit on the length of the command, except by the maximum 538 * packet size. Also sets the tty flag if there is no command. 539 */ 540 if (!ac) { 541 /* No command specified - execute shell on a tty. */ 542 tty_flag = 1; 543 if (subsystem_flag) { 544 fprintf(stderr, 545 "You must specify a subsystem to invoke.\n"); 546 usage(); 547 } 548 } else { 549 /* A command has been specified. Store it into the buffer. */ 550 for (i = 0; i < ac; i++) { 551 if (i) 552 buffer_append(&command, " ", 1); 553 buffer_append(&command, av[i], strlen(av[i])); 554 } 555 } 556 557 /* Cannot fork to background if no command. */ 558 if (fork_after_authentication_flag && buffer_len(&command) == 0 && !no_shell_flag) 559 fatal("Cannot fork into background without a command to execute."); 560 561 /* Allocate a tty by default if no command specified. */ 562 if (buffer_len(&command) == 0) 563 tty_flag = 1; 564 565 /* Force no tty */ 566 if (no_tty_flag) 567 tty_flag = 0; 568 /* Do not allocate a tty if stdin is not a tty. */ 569 if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) { 570 if (tty_flag) 571 logit("Pseudo-terminal will not be allocated because stdin is not a terminal."); 572 tty_flag = 0; 573 } 574 575 /* 576 * Initialize "log" output. Since we are the client all output 577 * actually goes to stderr. 578 */ 579 log_init(av[0], options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, 580 SYSLOG_FACILITY_USER, 1); 581 582 /* 583 * Read per-user configuration file. Ignore the system wide config 584 * file if the user specifies a config file on the command line. 585 */ 586 if (config != NULL) { 587 if (!read_config_file(config, host, &options, 0)) 588 fatal("Can't open user config file %.100s: " 589 "%.100s", config, strerror(errno)); 590 } else { 591 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir, 592 _PATH_SSH_USER_CONFFILE); 593 (void)read_config_file(buf, host, &options, 1); 594 595 /* Read systemwide configuration file after use config. */ 596 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, 597 &options, 0); 598 } 599 600 /* Fill configuration defaults. */ 601 fill_default_options(&options); 602 603 channel_set_af(options.address_family); 604 605 /* reinit */ 606 log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, 1); 607 608 seed_rng(); 609 610 if (options.user == NULL) 611 options.user = xstrdup(pw->pw_name); 612 613 if (options.hostname != NULL) 614 host = options.hostname; 615 616 /* Find canonic host name. */ 617 if (strchr(host, '.') == 0) { 618 struct addrinfo hints; 619 struct addrinfo *ai = NULL; 620 int errgai; 621 memset(&hints, 0, sizeof(hints)); 622 hints.ai_family = options.address_family; 623 hints.ai_flags = AI_CANONNAME; 624 hints.ai_socktype = SOCK_STREAM; 625 errgai = getaddrinfo(host, NULL, &hints, &ai); 626 if (errgai == 0) { 627 if (ai->ai_canonname != NULL) 628 host = xstrdup(ai->ai_canonname); 629 freeaddrinfo(ai); 630 } 631 } 632 633 /* force lowercase for hostkey matching */ 634 if (options.host_key_alias != NULL) { 635 for (p = options.host_key_alias; *p; p++) 636 if (isupper(*p)) 637 *p = tolower(*p); 638 } 639 640 /* Get default port if port has not been set. */ 641 if (options.port == 0) { 642 sp = getservbyname(SSH_SERVICE_NAME, "tcp"); 643 options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT; 644 } 645 646 if (options.proxy_command != NULL && 647 strcmp(options.proxy_command, "none") == 0) 648 options.proxy_command = NULL; 649 if (options.control_path != NULL && 650 strcmp(options.control_path, "none") == 0) 651 options.control_path = NULL; 652 653 if (options.control_path != NULL) { 654 snprintf(buf, sizeof(buf), "%d", options.port); 655 cp = tilde_expand_filename(options.control_path, 656 original_real_uid); 657 options.control_path = percent_expand(cp, "p", buf, "h", host, 658 "r", options.user, (char *)NULL); 659 xfree(cp); 660 } 661 if (mux_command != 0 && options.control_path == NULL) 662 fatal("No ControlPath specified for \"-O\" command"); 663 if (options.control_path != NULL) 664 control_client(options.control_path); 665 666 /* Open a connection to the remote host. */ 667 if (ssh_connect(host, &hostaddr, options.port, 668 options.address_family, options.connection_attempts, 669 #ifdef HAVE_CYGWIN 670 options.use_privileged_port, 671 #else 672 original_effective_uid == 0 && options.use_privileged_port, 673 #endif 674 options.proxy_command) != 0) 675 exit(255); 676 677 /* 678 * If we successfully made the connection, load the host private key 679 * in case we will need it later for combined rsa-rhosts 680 * authentication. This must be done before releasing extra 681 * privileges, because the file is only readable by root. 682 * If we cannot access the private keys, load the public keys 683 * instead and try to execute the ssh-keysign helper instead. 684 */ 685 sensitive_data.nkeys = 0; 686 sensitive_data.keys = NULL; 687 sensitive_data.external_keysign = 0; 688 if (options.rhosts_rsa_authentication || 689 options.hostbased_authentication) { 690 sensitive_data.nkeys = 3; 691 sensitive_data.keys = xmalloc(sensitive_data.nkeys * 692 sizeof(Key)); 693 694 PRIV_START; 695 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, 696 _PATH_HOST_KEY_FILE, "", NULL); 697 sensitive_data.keys[1] = key_load_private_type(KEY_DSA, 698 _PATH_HOST_DSA_KEY_FILE, "", NULL); 699 sensitive_data.keys[2] = key_load_private_type(KEY_RSA, 700 _PATH_HOST_RSA_KEY_FILE, "", NULL); 701 PRIV_END; 702 703 if (options.hostbased_authentication == 1 && 704 sensitive_data.keys[0] == NULL && 705 sensitive_data.keys[1] == NULL && 706 sensitive_data.keys[2] == NULL) { 707 sensitive_data.keys[1] = key_load_public( 708 _PATH_HOST_DSA_KEY_FILE, NULL); 709 sensitive_data.keys[2] = key_load_public( 710 _PATH_HOST_RSA_KEY_FILE, NULL); 711 sensitive_data.external_keysign = 1; 712 } 713 } 714 /* 715 * Get rid of any extra privileges that we may have. We will no 716 * longer need them. Also, extra privileges could make it very hard 717 * to read identity files and other non-world-readable files from the 718 * user's home directory if it happens to be on a NFS volume where 719 * root is mapped to nobody. 720 */ 721 if (original_effective_uid == 0) { 722 PRIV_START; 723 permanently_set_uid(pw); 724 } 725 726 /* 727 * Now that we are back to our own permissions, create ~/.ssh 728 * directory if it doesn't already exist. 729 */ 730 snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir, strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 731 if (stat(buf, &st) < 0) 732 if (mkdir(buf, 0700) < 0) 733 error("Could not create directory '%.200s'.", buf); 734 735 /* load options.identity_files */ 736 load_public_identity_files(); 737 738 /* Expand ~ in known host file names. */ 739 /* XXX mem-leaks: */ 740 options.system_hostfile = 741 tilde_expand_filename(options.system_hostfile, original_real_uid); 742 options.user_hostfile = 743 tilde_expand_filename(options.user_hostfile, original_real_uid); 744 options.system_hostfile2 = 745 tilde_expand_filename(options.system_hostfile2, original_real_uid); 746 options.user_hostfile2 = 747 tilde_expand_filename(options.user_hostfile2, original_real_uid); 748 749 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 750 751 /* Log into the remote system. This never returns if the login fails. */ 752 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, pw); 753 754 /* We no longer need the private host keys. Clear them now. */ 755 if (sensitive_data.nkeys != 0) { 756 for (i = 0; i < sensitive_data.nkeys; i++) { 757 if (sensitive_data.keys[i] != NULL) { 758 /* Destroys contents safely */ 759 debug3("clear hostkey %d", i); 760 key_free(sensitive_data.keys[i]); 761 sensitive_data.keys[i] = NULL; 762 } 763 } 764 xfree(sensitive_data.keys); 765 } 766 for (i = 0; i < options.num_identity_files; i++) { 767 if (options.identity_files[i]) { 768 xfree(options.identity_files[i]); 769 options.identity_files[i] = NULL; 770 } 771 if (options.identity_keys[i]) { 772 key_free(options.identity_keys[i]); 773 options.identity_keys[i] = NULL; 774 } 775 } 776 777 exit_status = compat20 ? ssh_session2() : ssh_session(); 778 packet_close(); 779 780 if (options.control_path != NULL && control_fd != -1) 781 unlink(options.control_path); 782 783 /* 784 * Send SIGHUP to proxy command if used. We don't wait() in 785 * case it hangs and instead rely on init to reap the child 786 */ 787 if (proxy_command_pid > 1) 788 kill(proxy_command_pid, SIGHUP); 789 790 return exit_status; 791 } 792 793 static void 794 ssh_init_forwarding(void) 795 { 796 int success = 0; 797 int i; 798 799 /* Initiate local TCP/IP port forwardings. */ 800 for (i = 0; i < options.num_local_forwards; i++) { 801 debug("Local connections to %.200s:%d forwarded to remote " 802 "address %.200s:%d", 803 (options.local_forwards[i].listen_host == NULL) ? 804 (options.gateway_ports ? "*" : "LOCALHOST") : 805 options.local_forwards[i].listen_host, 806 options.local_forwards[i].listen_port, 807 options.local_forwards[i].connect_host, 808 options.local_forwards[i].connect_port); 809 success += channel_setup_local_fwd_listener( 810 options.local_forwards[i].listen_host, 811 options.local_forwards[i].listen_port, 812 options.local_forwards[i].connect_host, 813 options.local_forwards[i].connect_port, 814 options.gateway_ports); 815 } 816 if (i > 0 && success == 0) 817 error("Could not request local forwarding."); 818 819 /* Initiate remote TCP/IP port forwardings. */ 820 for (i = 0; i < options.num_remote_forwards; i++) { 821 debug("Remote connections from %.200s:%d forwarded to " 822 "local address %.200s:%d", 823 (options.remote_forwards[i].listen_host == NULL) ? 824 "LOCALHOST" : options.remote_forwards[i].listen_host, 825 options.remote_forwards[i].listen_port, 826 options.remote_forwards[i].connect_host, 827 options.remote_forwards[i].connect_port); 828 channel_request_remote_forwarding( 829 options.remote_forwards[i].listen_host, 830 options.remote_forwards[i].listen_port, 831 options.remote_forwards[i].connect_host, 832 options.remote_forwards[i].connect_port); 833 } 834 } 835 836 static void 837 check_agent_present(void) 838 { 839 if (options.forward_agent) { 840 /* Clear agent forwarding if we don't have an agent. */ 841 if (!ssh_agent_present()) 842 options.forward_agent = 0; 843 } 844 } 845 846 static int 847 ssh_session(void) 848 { 849 int type; 850 int interactive = 0; 851 int have_tty = 0; 852 struct winsize ws; 853 char *cp; 854 const char *display; 855 856 /* Enable compression if requested. */ 857 if (options.compression) { 858 debug("Requesting compression at level %d.", options.compression_level); 859 860 if (options.compression_level < 1 || options.compression_level > 9) 861 fatal("Compression level must be from 1 (fast) to 9 (slow, best)."); 862 863 /* Send the request. */ 864 packet_start(SSH_CMSG_REQUEST_COMPRESSION); 865 packet_put_int(options.compression_level); 866 packet_send(); 867 packet_write_wait(); 868 type = packet_read(); 869 if (type == SSH_SMSG_SUCCESS) 870 packet_start_compression(options.compression_level); 871 else if (type == SSH_SMSG_FAILURE) 872 logit("Warning: Remote host refused compression."); 873 else 874 packet_disconnect("Protocol error waiting for compression response."); 875 } 876 /* Allocate a pseudo tty if appropriate. */ 877 if (tty_flag) { 878 debug("Requesting pty."); 879 880 /* Start the packet. */ 881 packet_start(SSH_CMSG_REQUEST_PTY); 882 883 /* Store TERM in the packet. There is no limit on the 884 length of the string. */ 885 cp = getenv("TERM"); 886 if (!cp) 887 cp = ""; 888 packet_put_cstring(cp); 889 890 /* Store window size in the packet. */ 891 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) 892 memset(&ws, 0, sizeof(ws)); 893 packet_put_int(ws.ws_row); 894 packet_put_int(ws.ws_col); 895 packet_put_int(ws.ws_xpixel); 896 packet_put_int(ws.ws_ypixel); 897 898 /* Store tty modes in the packet. */ 899 tty_make_modes(fileno(stdin), NULL); 900 901 /* Send the packet, and wait for it to leave. */ 902 packet_send(); 903 packet_write_wait(); 904 905 /* Read response from the server. */ 906 type = packet_read(); 907 if (type == SSH_SMSG_SUCCESS) { 908 interactive = 1; 909 have_tty = 1; 910 } else if (type == SSH_SMSG_FAILURE) 911 logit("Warning: Remote host failed or refused to allocate a pseudo tty."); 912 else 913 packet_disconnect("Protocol error waiting for pty request response."); 914 } 915 /* Request X11 forwarding if enabled and DISPLAY is set. */ 916 display = getenv("DISPLAY"); 917 if (options.forward_x11 && display != NULL) { 918 char *proto, *data; 919 /* Get reasonable local authentication information. */ 920 client_x11_get_proto(display, options.xauth_location, 921 options.forward_x11_trusted, &proto, &data); 922 /* Request forwarding with authentication spoofing. */ 923 debug("Requesting X11 forwarding with authentication spoofing."); 924 x11_request_forwarding_with_spoofing(0, display, proto, data); 925 926 /* Read response from the server. */ 927 type = packet_read(); 928 if (type == SSH_SMSG_SUCCESS) { 929 interactive = 1; 930 } else if (type == SSH_SMSG_FAILURE) { 931 logit("Warning: Remote host denied X11 forwarding."); 932 } else { 933 packet_disconnect("Protocol error waiting for X11 forwarding"); 934 } 935 } 936 /* Tell the packet module whether this is an interactive session. */ 937 packet_set_interactive(interactive); 938 939 /* Request authentication agent forwarding if appropriate. */ 940 check_agent_present(); 941 942 if (options.forward_agent) { 943 debug("Requesting authentication agent forwarding."); 944 auth_request_forwarding(); 945 946 /* Read response from the server. */ 947 type = packet_read(); 948 packet_check_eom(); 949 if (type != SSH_SMSG_SUCCESS) 950 logit("Warning: Remote host denied authentication agent forwarding."); 951 } 952 953 /* Initiate port forwardings. */ 954 ssh_init_forwarding(); 955 956 /* If requested, let ssh continue in the background. */ 957 if (fork_after_authentication_flag) 958 if (daemon(1, 1) < 0) 959 fatal("daemon() failed: %.200s", strerror(errno)); 960 961 /* 962 * If a command was specified on the command line, execute the 963 * command now. Otherwise request the server to start a shell. 964 */ 965 if (buffer_len(&command) > 0) { 966 int len = buffer_len(&command); 967 if (len > 900) 968 len = 900; 969 debug("Sending command: %.*s", len, (u_char *)buffer_ptr(&command)); 970 packet_start(SSH_CMSG_EXEC_CMD); 971 packet_put_string(buffer_ptr(&command), buffer_len(&command)); 972 packet_send(); 973 packet_write_wait(); 974 } else { 975 debug("Requesting shell."); 976 packet_start(SSH_CMSG_EXEC_SHELL); 977 packet_send(); 978 packet_write_wait(); 979 } 980 981 /* Enter the interactive session. */ 982 return client_loop(have_tty, tty_flag ? 983 options.escape_char : SSH_ESCAPECHAR_NONE, 0); 984 } 985 986 static void 987 ssh_subsystem_reply(int type, u_int32_t seq, void *ctxt) 988 { 989 int id, len; 990 991 id = packet_get_int(); 992 len = buffer_len(&command); 993 if (len > 900) 994 len = 900; 995 packet_check_eom(); 996 if (type == SSH2_MSG_CHANNEL_FAILURE) 997 fatal("Request for subsystem '%.*s' failed on channel %d", 998 len, (u_char *)buffer_ptr(&command), id); 999 } 1000 1001 void 1002 client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt) 1003 { 1004 int i; 1005 1006 i = client_global_request_id++; 1007 if (i >= options.num_remote_forwards) 1008 return; 1009 debug("remote forward %s for: listen %d, connect %s:%d", 1010 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 1011 options.remote_forwards[i].listen_port, 1012 options.remote_forwards[i].connect_host, 1013 options.remote_forwards[i].connect_port); 1014 if (type == SSH2_MSG_REQUEST_FAILURE) 1015 logit("Warning: remote port forwarding failed for listen " 1016 "port %d", options.remote_forwards[i].listen_port); 1017 } 1018 1019 static void 1020 ssh_control_listener(void) 1021 { 1022 struct sockaddr_un addr; 1023 mode_t old_umask; 1024 int addr_len; 1025 1026 if (options.control_path == NULL || 1027 options.control_master == SSHCTL_MASTER_NO) 1028 return; 1029 1030 debug("setting up multiplex master socket"); 1031 1032 memset(&addr, '\0', sizeof(addr)); 1033 addr.sun_family = AF_UNIX; 1034 addr_len = offsetof(struct sockaddr_un, sun_path) + 1035 strlen(options.control_path) + 1; 1036 1037 if (strlcpy(addr.sun_path, options.control_path, 1038 sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) 1039 fatal("ControlPath too long"); 1040 1041 if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) 1042 fatal("%s socket(): %s", __func__, strerror(errno)); 1043 1044 old_umask = umask(0177); 1045 if (bind(control_fd, (struct sockaddr*)&addr, addr_len) == -1) { 1046 control_fd = -1; 1047 if (errno == EINVAL || errno == EADDRINUSE) 1048 fatal("ControlSocket %s already exists", 1049 options.control_path); 1050 else 1051 fatal("%s bind(): %s", __func__, strerror(errno)); 1052 } 1053 umask(old_umask); 1054 1055 if (listen(control_fd, 64) == -1) 1056 fatal("%s listen(): %s", __func__, strerror(errno)); 1057 1058 set_nonblock(control_fd); 1059 } 1060 1061 /* request pty/x11/agent/tcpfwd/shell for channel */ 1062 static void 1063 ssh_session2_setup(int id, void *arg) 1064 { 1065 extern char **environ; 1066 const char *display; 1067 int interactive = tty_flag; 1068 1069 display = getenv("DISPLAY"); 1070 if (options.forward_x11 && display != NULL) { 1071 char *proto, *data; 1072 /* Get reasonable local authentication information. */ 1073 client_x11_get_proto(display, options.xauth_location, 1074 options.forward_x11_trusted, &proto, &data); 1075 /* Request forwarding with authentication spoofing. */ 1076 debug("Requesting X11 forwarding with authentication spoofing."); 1077 x11_request_forwarding_with_spoofing(id, display, proto, data); 1078 interactive = 1; 1079 /* XXX wait for reply */ 1080 } 1081 1082 check_agent_present(); 1083 if (options.forward_agent) { 1084 debug("Requesting authentication agent forwarding."); 1085 channel_request_start(id, "auth-agent-req@openssh.com", 0); 1086 packet_send(); 1087 } 1088 1089 if (options.tun_open != SSH_TUNMODE_NO) { 1090 Channel *c; 1091 int fd; 1092 1093 debug("Requesting tun."); 1094 if ((fd = tun_open(options.tun_local, 1095 options.tun_open)) >= 0) { 1096 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1, 1097 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 1098 0, "tun", 1); 1099 c->datagram = 1; 1100 #if defined(SSH_TUN_FILTER) 1101 if (options.tun_open == SSH_TUNMODE_POINTOPOINT) 1102 channel_register_filter(c->self, sys_tun_infilter, 1103 sys_tun_outfilter); 1104 #endif 1105 packet_start(SSH2_MSG_CHANNEL_OPEN); 1106 packet_put_cstring("tun@openssh.com"); 1107 packet_put_int(c->self); 1108 packet_put_int(c->local_window_max); 1109 packet_put_int(c->local_maxpacket); 1110 packet_put_int(options.tun_open); 1111 packet_put_int(options.tun_remote); 1112 packet_send(); 1113 } 1114 } 1115 1116 client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), 1117 NULL, fileno(stdin), &command, environ, &ssh_subsystem_reply); 1118 1119 packet_set_interactive(interactive); 1120 } 1121 1122 /* open new channel for a session */ 1123 static int 1124 ssh_session2_open(void) 1125 { 1126 Channel *c; 1127 int window, packetmax, in, out, err; 1128 1129 if (stdin_null_flag) { 1130 in = open(_PATH_DEVNULL, O_RDONLY); 1131 } else { 1132 in = dup(STDIN_FILENO); 1133 } 1134 out = dup(STDOUT_FILENO); 1135 err = dup(STDERR_FILENO); 1136 1137 if (in < 0 || out < 0 || err < 0) 1138 fatal("dup() in/out/err failed"); 1139 1140 /* enable nonblocking unless tty */ 1141 if (!isatty(in)) 1142 set_nonblock(in); 1143 if (!isatty(out)) 1144 set_nonblock(out); 1145 if (!isatty(err)) 1146 set_nonblock(err); 1147 1148 window = CHAN_SES_WINDOW_DEFAULT; 1149 packetmax = CHAN_SES_PACKET_DEFAULT; 1150 if (tty_flag) { 1151 window >>= 1; 1152 packetmax >>= 1; 1153 } 1154 c = channel_new( 1155 "session", SSH_CHANNEL_OPENING, in, out, err, 1156 window, packetmax, CHAN_EXTENDED_WRITE, 1157 "client-session", /*nonblock*/0); 1158 1159 debug3("ssh_session2_open: channel_new: %d", c->self); 1160 1161 channel_send_open(c->self); 1162 if (!no_shell_flag) 1163 channel_register_confirm(c->self, ssh_session2_setup, NULL); 1164 1165 return c->self; 1166 } 1167 1168 static int 1169 ssh_session2(void) 1170 { 1171 int id = -1; 1172 1173 /* XXX should be pre-session */ 1174 ssh_init_forwarding(); 1175 ssh_control_listener(); 1176 1177 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) 1178 id = ssh_session2_open(); 1179 1180 /* Execute a local command */ 1181 if (options.local_command != NULL && 1182 options.permit_local_command) 1183 ssh_local_cmd(options.local_command); 1184 1185 /* If requested, let ssh continue in the background. */ 1186 if (fork_after_authentication_flag) 1187 if (daemon(1, 1) < 0) 1188 fatal("daemon() failed: %.200s", strerror(errno)); 1189 1190 return client_loop(tty_flag, tty_flag ? 1191 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1192 } 1193 1194 static void 1195 load_public_identity_files(void) 1196 { 1197 char *filename; 1198 int i = 0; 1199 Key *public; 1200 #ifdef SMARTCARD 1201 Key **keys; 1202 1203 if (options.smartcard_device != NULL && 1204 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 1205 (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL ) { 1206 int count = 0; 1207 for (i = 0; keys[i] != NULL; i++) { 1208 count++; 1209 memmove(&options.identity_files[1], &options.identity_files[0], 1210 sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1)); 1211 memmove(&options.identity_keys[1], &options.identity_keys[0], 1212 sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1)); 1213 options.num_identity_files++; 1214 options.identity_keys[0] = keys[i]; 1215 options.identity_files[0] = sc_get_key_label(keys[i]); 1216 } 1217 if (options.num_identity_files > SSH_MAX_IDENTITY_FILES) 1218 options.num_identity_files = SSH_MAX_IDENTITY_FILES; 1219 i = count; 1220 xfree(keys); 1221 } 1222 #endif /* SMARTCARD */ 1223 for (; i < options.num_identity_files; i++) { 1224 filename = tilde_expand_filename(options.identity_files[i], 1225 original_real_uid); 1226 public = key_load_public(filename, NULL); 1227 debug("identity file %s type %d", filename, 1228 public ? public->type : -1); 1229 xfree(options.identity_files[i]); 1230 options.identity_files[i] = filename; 1231 options.identity_keys[i] = public; 1232 } 1233 } 1234 1235 static void 1236 control_client_sighandler(int signo) 1237 { 1238 control_client_terminate = signo; 1239 } 1240 1241 static void 1242 control_client_sigrelay(int signo) 1243 { 1244 if (control_server_pid > 1) 1245 kill(control_server_pid, signo); 1246 } 1247 1248 static int 1249 env_permitted(char *env) 1250 { 1251 int i; 1252 char name[1024], *cp; 1253 1254 strlcpy(name, env, sizeof(name)); 1255 if ((cp = strchr(name, '=')) == NULL) 1256 return (0); 1257 1258 *cp = '\0'; 1259 1260 for (i = 0; i < options.num_send_env; i++) 1261 if (match_pattern(name, options.send_env[i])) 1262 return (1); 1263 1264 return (0); 1265 } 1266 1267 static void 1268 control_client(const char *path) 1269 { 1270 struct sockaddr_un addr; 1271 int i, r, fd, sock, exitval, num_env, addr_len; 1272 Buffer m; 1273 char *term; 1274 extern char **environ; 1275 u_int flags; 1276 1277 if (mux_command == 0) 1278 mux_command = SSHMUX_COMMAND_OPEN; 1279 1280 switch (options.control_master) { 1281 case SSHCTL_MASTER_AUTO: 1282 case SSHCTL_MASTER_AUTO_ASK: 1283 debug("auto-mux: Trying existing master"); 1284 /* FALLTHROUGH */ 1285 case SSHCTL_MASTER_NO: 1286 break; 1287 default: 1288 return; 1289 } 1290 1291 memset(&addr, '\0', sizeof(addr)); 1292 addr.sun_family = AF_UNIX; 1293 addr_len = offsetof(struct sockaddr_un, sun_path) + 1294 strlen(path) + 1; 1295 1296 if (strlcpy(addr.sun_path, path, 1297 sizeof(addr.sun_path)) >= sizeof(addr.sun_path)) 1298 fatal("ControlPath too long"); 1299 1300 if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0) 1301 fatal("%s socket(): %s", __func__, strerror(errno)); 1302 1303 if (connect(sock, (struct sockaddr*)&addr, addr_len) == -1) { 1304 if (mux_command != SSHMUX_COMMAND_OPEN) { 1305 fatal("Control socket connect(%.100s): %s", path, 1306 strerror(errno)); 1307 } 1308 if (errno == ENOENT) 1309 debug("Control socket \"%.100s\" does not exist", path); 1310 else { 1311 error("Control socket connect(%.100s): %s", path, 1312 strerror(errno)); 1313 } 1314 close(sock); 1315 return; 1316 } 1317 1318 if (stdin_null_flag) { 1319 if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1) 1320 fatal("open(/dev/null): %s", strerror(errno)); 1321 if (dup2(fd, STDIN_FILENO) == -1) 1322 fatal("dup2: %s", strerror(errno)); 1323 if (fd > STDERR_FILENO) 1324 close(fd); 1325 } 1326 1327 term = getenv("TERM"); 1328 1329 flags = 0; 1330 if (tty_flag) 1331 flags |= SSHMUX_FLAG_TTY; 1332 if (subsystem_flag) 1333 flags |= SSHMUX_FLAG_SUBSYS; 1334 if (options.forward_x11) 1335 flags |= SSHMUX_FLAG_X11_FWD; 1336 if (options.forward_agent) 1337 flags |= SSHMUX_FLAG_AGENT_FWD; 1338 1339 buffer_init(&m); 1340 1341 /* Send our command to server */ 1342 buffer_put_int(&m, mux_command); 1343 buffer_put_int(&m, flags); 1344 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) 1345 fatal("%s: msg_send", __func__); 1346 buffer_clear(&m); 1347 1348 /* Get authorisation status and PID of controlee */ 1349 if (ssh_msg_recv(sock, &m) == -1) 1350 fatal("%s: msg_recv", __func__); 1351 if (buffer_get_char(&m) != SSHMUX_VER) 1352 fatal("%s: wrong version", __func__); 1353 if (buffer_get_int(&m) != 1) 1354 fatal("Connection to master denied"); 1355 control_server_pid = buffer_get_int(&m); 1356 1357 buffer_clear(&m); 1358 1359 switch (mux_command) { 1360 case SSHMUX_COMMAND_ALIVE_CHECK: 1361 fprintf(stderr, "Master running (pid=%d)\r\n", 1362 control_server_pid); 1363 exit(0); 1364 case SSHMUX_COMMAND_TERMINATE: 1365 fprintf(stderr, "Exit request sent.\r\n"); 1366 exit(0); 1367 case SSHMUX_COMMAND_OPEN: 1368 /* continue below */ 1369 break; 1370 default: 1371 fatal("silly mux_command %d", mux_command); 1372 } 1373 1374 /* SSHMUX_COMMAND_OPEN */ 1375 buffer_put_cstring(&m, term ? term : ""); 1376 buffer_append(&command, "\0", 1); 1377 buffer_put_cstring(&m, buffer_ptr(&command)); 1378 1379 if (options.num_send_env == 0 || environ == NULL) { 1380 buffer_put_int(&m, 0); 1381 } else { 1382 /* Pass environment */ 1383 num_env = 0; 1384 for (i = 0; environ[i] != NULL; i++) 1385 if (env_permitted(environ[i])) 1386 num_env++; /* Count */ 1387 1388 buffer_put_int(&m, num_env); 1389 1390 for (i = 0; environ[i] != NULL && num_env >= 0; i++) 1391 if (env_permitted(environ[i])) { 1392 num_env--; 1393 buffer_put_cstring(&m, environ[i]); 1394 } 1395 } 1396 1397 if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) 1398 fatal("%s: msg_send", __func__); 1399 1400 mm_send_fd(sock, STDIN_FILENO); 1401 mm_send_fd(sock, STDOUT_FILENO); 1402 mm_send_fd(sock, STDERR_FILENO); 1403 1404 /* Wait for reply, so master has a chance to gather ttymodes */ 1405 buffer_clear(&m); 1406 if (ssh_msg_recv(sock, &m) == -1) 1407 fatal("%s: msg_recv", __func__); 1408 if (buffer_get_char(&m) != SSHMUX_VER) 1409 fatal("%s: wrong version", __func__); 1410 buffer_free(&m); 1411 1412 signal(SIGHUP, control_client_sighandler); 1413 signal(SIGINT, control_client_sighandler); 1414 signal(SIGTERM, control_client_sighandler); 1415 signal(SIGWINCH, control_client_sigrelay); 1416 1417 if (tty_flag) 1418 enter_raw_mode(); 1419 1420 /* Stick around until the controlee closes the client_fd */ 1421 exitval = 0; 1422 for (;!control_client_terminate;) { 1423 r = read(sock, &exitval, sizeof(exitval)); 1424 if (r == 0) { 1425 debug2("Received EOF from master"); 1426 break; 1427 } 1428 if (r > 0) 1429 debug2("Received exit status from master %d", exitval); 1430 if (r == -1 && errno != EINTR) 1431 fatal("%s: read %s", __func__, strerror(errno)); 1432 } 1433 1434 if (control_client_terminate) 1435 debug2("Exiting on signal %d", control_client_terminate); 1436 1437 close(sock); 1438 1439 leave_raw_mode(); 1440 1441 if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET) 1442 fprintf(stderr, "Connection to master closed.\r\n"); 1443 1444 exit(exitval); 1445 } 1446