1 /* $OpenBSD: ssh.c,v 1.346 2010/08/12 21:49:44 djm Exp $ */ 2 /* 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 * 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. 17 * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. 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. 41 */ 42 43 #include "includes.h" 44 45 #include <sys/types.h> 46 #ifdef HAVE_SYS_STAT_H 47 # include <sys/stat.h> 48 #endif 49 #include <sys/resource.h> 50 #include <sys/ioctl.h> 51 #include <sys/param.h> 52 #include <sys/socket.h> 53 54 #include <ctype.h> 55 #include <errno.h> 56 #include <fcntl.h> 57 #include <netdb.h> 58 #ifdef HAVE_PATHS_H 59 #include <paths.h> 60 #endif 61 #include <pwd.h> 62 #include <signal.h> 63 #include <stdarg.h> 64 #include <stddef.h> 65 #include <stdio.h> 66 #include <stdlib.h> 67 #include <string.h> 68 #include <unistd.h> 69 70 #include <netinet/in.h> 71 #include <arpa/inet.h> 72 73 #include <openssl/evp.h> 74 #include <openssl/err.h> 75 #include "openbsd-compat/openssl-compat.h" 76 #include "openbsd-compat/sys-queue.h" 77 78 #include "xmalloc.h" 79 #include "ssh.h" 80 #include "ssh1.h" 81 #include "ssh2.h" 82 #include "canohost.h" 83 #include "compat.h" 84 #include "cipher.h" 85 #include "packet.h" 86 #include "buffer.h" 87 #include "channels.h" 88 #include "key.h" 89 #include "authfd.h" 90 #include "authfile.h" 91 #include "pathnames.h" 92 #include "dispatch.h" 93 #include "clientloop.h" 94 #include "log.h" 95 #include "readconf.h" 96 #include "sshconnect.h" 97 #include "misc.h" 98 #include "kex.h" 99 #include "mac.h" 100 #include "sshpty.h" 101 #include "match.h" 102 #include "msg.h" 103 #include "uidswap.h" 104 #include "roaming.h" 105 #include "version.h" 106 107 #ifdef ENABLE_PKCS11 108 #include "ssh-pkcs11.h" 109 #endif 110 111 extern char *__progname; 112 113 /* Flag indicating whether debug mode is on. May be set on the command line. */ 114 int debug_flag = 0; 115 116 /* Flag indicating whether a tty should be allocated */ 117 int tty_flag = 0; 118 int no_tty_flag = 0; 119 int force_tty_flag = 0; 120 121 /* don't exec a shell */ 122 int no_shell_flag = 0; 123 124 /* 125 * Flag indicating that nothing should be read from stdin. This can be set 126 * on the command line. 127 */ 128 int stdin_null_flag = 0; 129 130 /* 131 * Flag indicating that the current process should be backgrounded and 132 * a new slave launched in the foreground for ControlPersist. 133 */ 134 int need_controlpersist_detach = 0; 135 136 /* Copies of flags for ControlPersist foreground slave */ 137 int ostdin_null_flag, ono_shell_flag, ono_tty_flag, otty_flag; 138 139 /* 140 * Flag indicating that ssh should fork after authentication. This is useful 141 * so that the passphrase can be entered manually, and then ssh goes to the 142 * background. 143 */ 144 int fork_after_authentication_flag = 0; 145 146 /* forward stdio to remote host and port */ 147 char *stdio_forward_host = NULL; 148 int stdio_forward_port = 0; 149 150 /* 151 * General data structure for command line options and options configurable 152 * in configuration files. See readconf.h. 153 */ 154 Options options; 155 156 /* optional user configfile */ 157 char *config = NULL; 158 159 /* 160 * Name of the host we are connecting to. This is the name given on the 161 * command line, or the HostName specified for the user-supplied name in a 162 * configuration file. 163 */ 164 char *host; 165 166 /* socket address the host resolves to */ 167 struct sockaddr_storage hostaddr; 168 169 /* Private host keys. */ 170 Sensitive sensitive_data; 171 172 /* Original real UID. */ 173 uid_t original_real_uid; 174 uid_t original_effective_uid; 175 176 /* command to be executed */ 177 Buffer command; 178 179 /* Should we execute a command or invoke a subsystem? */ 180 int subsystem_flag = 0; 181 182 /* # of replies received for global requests */ 183 static int remote_forward_confirms_received = 0; 184 185 /* pid of proxycommand child process */ 186 pid_t proxy_command_pid = 0; 187 188 /* mux.c */ 189 extern int muxserver_sock; 190 extern u_int muxclient_command; 191 192 /* Prints a help message to the user. This function never returns. */ 193 194 static void 195 usage(void) 196 { 197 fprintf(stderr, 198 "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n" 199 " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n" 200 " [-I pkcs11] [-i identity_file]\n" 201 " [-L [bind_address:]port:host:hostport]\n" 202 " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n" 203 " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n" 204 " [-W host:port] [-w local_tun[:remote_tun]]\n" 205 " [user@]hostname [command]\n" 206 ); 207 exit(255); 208 } 209 210 static int ssh_session(void); 211 static int ssh_session2(void); 212 static void load_public_identity_files(void); 213 214 /* from muxclient.c */ 215 void muxclient(const char *); 216 void muxserver_listen(void); 217 218 /* 219 * Main program for the ssh client. 220 */ 221 int 222 main(int ac, char **av) 223 { 224 int i, r, opt, exit_status, use_syslog; 225 char *p, *cp, *line, *argv0, buf[MAXPATHLEN]; 226 struct stat st; 227 struct passwd *pw; 228 int dummy, timeout_ms; 229 extern int optind, optreset; 230 extern char *optarg; 231 struct servent *sp; 232 Forward fwd; 233 234 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 235 sanitise_stdfd(); 236 237 __progname = ssh_get_progname(av[0]); 238 init_rng(); 239 240 /* 241 * Discard other fds that are hanging around. These can cause problem 242 * with backgrounded ssh processes started by ControlPersist. 243 */ 244 closefrom(STDERR_FILENO + 1); 245 246 /* 247 * Save the original real uid. It will be needed later (uid-swapping 248 * may clobber the real uid). 249 */ 250 original_real_uid = getuid(); 251 original_effective_uid = geteuid(); 252 253 /* 254 * Use uid-swapping to give up root privileges for the duration of 255 * option processing. We will re-instantiate the rights when we are 256 * ready to create the privileged port, and will permanently drop 257 * them when the port has been created (actually, when the connection 258 * has been made, as we may need to create the port several times). 259 */ 260 PRIV_END; 261 262 #ifdef HAVE_SETRLIMIT 263 /* If we are installed setuid root be careful to not drop core. */ 264 if (original_real_uid != original_effective_uid) { 265 struct rlimit rlim; 266 rlim.rlim_cur = rlim.rlim_max = 0; 267 if (setrlimit(RLIMIT_CORE, &rlim) < 0) 268 fatal("setrlimit failed: %.100s", strerror(errno)); 269 } 270 #endif 271 /* Get user data. */ 272 pw = getpwuid(original_real_uid); 273 if (!pw) { 274 logit("You don't exist, go away!"); 275 exit(255); 276 } 277 /* Take a copy of the returned structure. */ 278 pw = pwcopy(pw); 279 280 /* 281 * Set our umask to something reasonable, as some files are created 282 * with the default umask. This will make them world-readable but 283 * writable only by the owner, which is ok for all files for which we 284 * don't set the modes explicitly. 285 */ 286 umask(022); 287 288 /* 289 * Initialize option structure to indicate that no values have been 290 * set. 291 */ 292 initialize_options(&options); 293 294 /* Parse command-line arguments. */ 295 host = NULL; 296 use_syslog = 0; 297 argv0 = av[0]; 298 299 again: 300 while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" 301 "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) { 302 switch (opt) { 303 case '1': 304 options.protocol = SSH_PROTO_1; 305 break; 306 case '2': 307 options.protocol = SSH_PROTO_2; 308 break; 309 case '4': 310 options.address_family = AF_INET; 311 break; 312 case '6': 313 options.address_family = AF_INET6; 314 break; 315 case 'n': 316 stdin_null_flag = 1; 317 break; 318 case 'f': 319 fork_after_authentication_flag = 1; 320 stdin_null_flag = 1; 321 break; 322 case 'x': 323 options.forward_x11 = 0; 324 break; 325 case 'X': 326 options.forward_x11 = 1; 327 break; 328 case 'y': 329 use_syslog = 1; 330 break; 331 case 'Y': 332 options.forward_x11 = 1; 333 options.forward_x11_trusted = 1; 334 break; 335 case 'g': 336 options.gateway_ports = 1; 337 break; 338 case 'O': 339 if (stdio_forward_host != NULL) 340 fatal("Cannot specify multiplexing " 341 "command with -W"); 342 else if (muxclient_command != 0) 343 fatal("Multiplexing command already specified"); 344 if (strcmp(optarg, "check") == 0) 345 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; 346 else if (strcmp(optarg, "forward") == 0) 347 muxclient_command = SSHMUX_COMMAND_FORWARD; 348 else if (strcmp(optarg, "exit") == 0) 349 muxclient_command = SSHMUX_COMMAND_TERMINATE; 350 else 351 fatal("Invalid multiplex command."); 352 break; 353 case 'P': /* deprecated */ 354 options.use_privileged_port = 0; 355 break; 356 case 'a': 357 options.forward_agent = 0; 358 break; 359 case 'A': 360 options.forward_agent = 1; 361 break; 362 case 'k': 363 options.gss_deleg_creds = 0; 364 break; 365 case 'K': 366 options.gss_authentication = 1; 367 options.gss_deleg_creds = 1; 368 break; 369 case 'i': 370 if (stat(optarg, &st) < 0) { 371 fprintf(stderr, "Warning: Identity file %s " 372 "not accessible: %s.\n", optarg, 373 strerror(errno)); 374 break; 375 } 376 if (options.num_identity_files >= 377 SSH_MAX_IDENTITY_FILES) 378 fatal("Too many identity files specified " 379 "(max %d)", SSH_MAX_IDENTITY_FILES); 380 options.identity_files[options.num_identity_files++] = 381 xstrdup(optarg); 382 break; 383 case 'I': 384 #ifdef ENABLE_PKCS11 385 options.pkcs11_provider = xstrdup(optarg); 386 #else 387 fprintf(stderr, "no support for PKCS#11.\n"); 388 #endif 389 break; 390 case 't': 391 if (tty_flag) 392 force_tty_flag = 1; 393 tty_flag = 1; 394 break; 395 case 'v': 396 if (debug_flag == 0) { 397 debug_flag = 1; 398 options.log_level = SYSLOG_LEVEL_DEBUG1; 399 } else { 400 if (options.log_level < SYSLOG_LEVEL_DEBUG3) 401 options.log_level++; 402 break; 403 } 404 /* FALLTHROUGH */ 405 case 'V': 406 fprintf(stderr, "%s, %s\n", 407 SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); 408 if (opt == 'V') 409 exit(0); 410 break; 411 case 'w': 412 if (options.tun_open == -1) 413 options.tun_open = SSH_TUNMODE_DEFAULT; 414 options.tun_local = a2tun(optarg, &options.tun_remote); 415 if (options.tun_local == SSH_TUNID_ERR) { 416 fprintf(stderr, 417 "Bad tun device '%s'\n", optarg); 418 exit(255); 419 } 420 break; 421 case 'W': 422 if (stdio_forward_host != NULL) 423 fatal("stdio forward already specified"); 424 if (muxclient_command != 0) 425 fatal("Cannot specify stdio forward with -O"); 426 if (parse_forward(&fwd, optarg, 1, 0)) { 427 stdio_forward_host = fwd.listen_host; 428 stdio_forward_port = fwd.listen_port; 429 xfree(fwd.connect_host); 430 } else { 431 fprintf(stderr, 432 "Bad stdio forwarding specification '%s'\n", 433 optarg); 434 exit(255); 435 } 436 no_tty_flag = 1; 437 no_shell_flag = 1; 438 options.clear_forwardings = 1; 439 options.exit_on_forward_failure = 1; 440 break; 441 case 'q': 442 options.log_level = SYSLOG_LEVEL_QUIET; 443 break; 444 case 'e': 445 if (optarg[0] == '^' && optarg[2] == 0 && 446 (u_char) optarg[1] >= 64 && 447 (u_char) optarg[1] < 128) 448 options.escape_char = (u_char) optarg[1] & 31; 449 else if (strlen(optarg) == 1) 450 options.escape_char = (u_char) optarg[0]; 451 else if (strcmp(optarg, "none") == 0) 452 options.escape_char = SSH_ESCAPECHAR_NONE; 453 else { 454 fprintf(stderr, "Bad escape character '%s'.\n", 455 optarg); 456 exit(255); 457 } 458 break; 459 case 'c': 460 if (ciphers_valid(optarg)) { 461 /* SSH2 only */ 462 options.ciphers = xstrdup(optarg); 463 options.cipher = SSH_CIPHER_INVALID; 464 } else { 465 /* SSH1 only */ 466 options.cipher = cipher_number(optarg); 467 if (options.cipher == -1) { 468 fprintf(stderr, 469 "Unknown cipher type '%s'\n", 470 optarg); 471 exit(255); 472 } 473 if (options.cipher == SSH_CIPHER_3DES) 474 options.ciphers = "3des-cbc"; 475 else if (options.cipher == SSH_CIPHER_BLOWFISH) 476 options.ciphers = "blowfish-cbc"; 477 else 478 options.ciphers = (char *)-1; 479 } 480 break; 481 case 'm': 482 if (mac_valid(optarg)) 483 options.macs = xstrdup(optarg); 484 else { 485 fprintf(stderr, "Unknown mac type '%s'\n", 486 optarg); 487 exit(255); 488 } 489 break; 490 case 'M': 491 if (options.control_master == SSHCTL_MASTER_YES) 492 options.control_master = SSHCTL_MASTER_ASK; 493 else 494 options.control_master = SSHCTL_MASTER_YES; 495 break; 496 case 'p': 497 options.port = a2port(optarg); 498 if (options.port <= 0) { 499 fprintf(stderr, "Bad port '%s'\n", optarg); 500 exit(255); 501 } 502 break; 503 case 'l': 504 options.user = optarg; 505 break; 506 507 case 'L': 508 if (parse_forward(&fwd, optarg, 0, 0)) 509 add_local_forward(&options, &fwd); 510 else { 511 fprintf(stderr, 512 "Bad local forwarding specification '%s'\n", 513 optarg); 514 exit(255); 515 } 516 break; 517 518 case 'R': 519 if (parse_forward(&fwd, optarg, 0, 1)) { 520 add_remote_forward(&options, &fwd); 521 } else { 522 fprintf(stderr, 523 "Bad remote forwarding specification " 524 "'%s'\n", optarg); 525 exit(255); 526 } 527 break; 528 529 case 'D': 530 if (parse_forward(&fwd, optarg, 1, 0)) { 531 add_local_forward(&options, &fwd); 532 } else { 533 fprintf(stderr, 534 "Bad dynamic forwarding specification " 535 "'%s'\n", optarg); 536 exit(255); 537 } 538 break; 539 540 case 'C': 541 options.compression = 1; 542 break; 543 case 'N': 544 no_shell_flag = 1; 545 no_tty_flag = 1; 546 break; 547 case 'o': 548 dummy = 1; 549 line = xstrdup(optarg); 550 if (process_config_line(&options, host ? host : "", 551 line, "command-line", 0, &dummy) != 0) 552 exit(255); 553 xfree(line); 554 break; 555 case 'T': 556 no_tty_flag = 1; 557 /* ensure that the user doesn't try to backdoor a */ 558 /* null cipher switch on an interactive session */ 559 /* so explicitly disable it no matter what */ 560 options.none_switch=0; 561 break; 562 case 's': 563 subsystem_flag = 1; 564 break; 565 case 'S': 566 if (options.control_path != NULL) 567 free(options.control_path); 568 options.control_path = xstrdup(optarg); 569 break; 570 case 'b': 571 options.bind_address = optarg; 572 break; 573 case 'F': 574 config = optarg; 575 break; 576 default: 577 usage(); 578 } 579 } 580 581 ac -= optind; 582 av += optind; 583 584 if (ac > 0 && !host) { 585 if (strrchr(*av, '@')) { 586 p = xstrdup(*av); 587 cp = strrchr(p, '@'); 588 if (cp == NULL || cp == p) 589 usage(); 590 options.user = p; 591 *cp = '\0'; 592 host = ++cp; 593 } else 594 host = *av; 595 if (ac > 1) { 596 optind = optreset = 1; 597 goto again; 598 } 599 ac--, av++; 600 } 601 602 /* Check that we got a host name. */ 603 if (!host) 604 usage(); 605 606 SSLeay_add_all_algorithms(); 607 ERR_load_crypto_strings(); 608 609 /* Initialize the command to execute on remote host. */ 610 buffer_init(&command); 611 612 /* 613 * Save the command to execute on the remote host in a buffer. There 614 * is no limit on the length of the command, except by the maximum 615 * packet size. Also sets the tty flag if there is no command. 616 */ 617 if (!ac) { 618 /* No command specified - execute shell on a tty. */ 619 tty_flag = 1; 620 if (subsystem_flag) { 621 fprintf(stderr, 622 "You must specify a subsystem to invoke.\n"); 623 usage(); 624 } 625 } else { 626 /* A command has been specified. Store it into the buffer. */ 627 for (i = 0; i < ac; i++) { 628 if (i) 629 buffer_append(&command, " ", 1); 630 buffer_append(&command, av[i], strlen(av[i])); 631 } 632 } 633 634 /* Cannot fork to background if no command. */ 635 if (fork_after_authentication_flag && buffer_len(&command) == 0 && 636 !no_shell_flag) 637 fatal("Cannot fork into background without a command " 638 "to execute."); 639 640 /* Allocate a tty by default if no command specified. */ 641 if (buffer_len(&command) == 0) 642 tty_flag = 1; 643 644 /* Force no tty */ 645 if (no_tty_flag || muxclient_command != 0) 646 tty_flag = 0; 647 /* Do not allocate a tty if stdin is not a tty. */ 648 if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) { 649 if (tty_flag) 650 logit("Pseudo-terminal will not be allocated because " 651 "stdin is not a terminal."); 652 tty_flag = 0; 653 } 654 655 /* 656 * Initialize "log" output. Since we are the client all output 657 * actually goes to stderr. 658 */ 659 log_init(argv0, 660 options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, 661 SYSLOG_FACILITY_USER, !use_syslog); 662 663 /* 664 * Read per-user configuration file. Ignore the system wide config 665 * file if the user specifies a config file on the command line. 666 */ 667 if (config != NULL) { 668 if (!read_config_file(config, host, &options, 0)) 669 fatal("Can't open user config file %.100s: " 670 "%.100s", config, strerror(errno)); 671 } else { 672 r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, 673 _PATH_SSH_USER_CONFFILE); 674 if (r > 0 && (size_t)r < sizeof(buf)) 675 (void)read_config_file(buf, host, &options, 1); 676 677 /* Read systemwide configuration file after use config. */ 678 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host, 679 &options, 0); 680 } 681 682 /* Fill configuration defaults. */ 683 fill_default_options(&options); 684 685 channel_set_af(options.address_family); 686 687 /* reinit */ 688 log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog); 689 690 seed_rng(); 691 692 if (options.user == NULL) 693 options.user = xstrdup(pw->pw_name); 694 695 /* Get default port if port has not been set. */ 696 if (options.port == 0) { 697 sp = getservbyname(SSH_SERVICE_NAME, "tcp"); 698 options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT; 699 } 700 701 if (options.hostname != NULL) { 702 host = percent_expand(options.hostname, 703 "h", host, (char *)NULL); 704 } 705 706 if (options.local_command != NULL) { 707 char thishost[NI_MAXHOST]; 708 709 if (gethostname(thishost, sizeof(thishost)) == -1) 710 fatal("gethostname: %s", strerror(errno)); 711 snprintf(buf, sizeof(buf), "%d", options.port); 712 debug3("expanding LocalCommand: %s", options.local_command); 713 cp = options.local_command; 714 options.local_command = percent_expand(cp, "d", pw->pw_dir, 715 "h", host, "l", thishost, "n", host, "r", options.user, 716 "p", buf, "u", pw->pw_name, (char *)NULL); 717 debug3("expanded LocalCommand: %s", options.local_command); 718 xfree(cp); 719 } 720 721 /* force lowercase for hostkey matching */ 722 if (options.host_key_alias != NULL) { 723 for (p = options.host_key_alias; *p; p++) 724 if (isupper(*p)) 725 *p = (char)tolower(*p); 726 } 727 728 if (options.proxy_command != NULL && 729 strcmp(options.proxy_command, "none") == 0) { 730 xfree(options.proxy_command); 731 options.proxy_command = NULL; 732 } 733 if (options.control_path != NULL && 734 strcmp(options.control_path, "none") == 0) { 735 xfree(options.control_path); 736 options.control_path = NULL; 737 } 738 739 if (options.control_path != NULL) { 740 char thishost[NI_MAXHOST]; 741 742 if (gethostname(thishost, sizeof(thishost)) == -1) 743 fatal("gethostname: %s", strerror(errno)); 744 snprintf(buf, sizeof(buf), "%d", options.port); 745 cp = tilde_expand_filename(options.control_path, 746 original_real_uid); 747 xfree(options.control_path); 748 options.control_path = percent_expand(cp, "p", buf, "h", host, 749 "r", options.user, "l", thishost, (char *)NULL); 750 xfree(cp); 751 } 752 if (muxclient_command != 0 && options.control_path == NULL) 753 fatal("No ControlPath specified for \"-O\" command"); 754 if (options.control_path != NULL) 755 muxclient(options.control_path); 756 757 timeout_ms = options.connection_timeout * 1000; 758 759 /* Open a connection to the remote host. */ 760 if (ssh_connect(host, &hostaddr, options.port, 761 options.address_family, options.connection_attempts, &timeout_ms, 762 options.tcp_keep_alive, 763 #ifdef HAVE_CYGWIN 764 options.use_privileged_port, 765 #else 766 original_effective_uid == 0 && options.use_privileged_port, 767 #endif 768 options.proxy_command) != 0) 769 exit(255); 770 771 if (timeout_ms > 0) 772 debug3("timeout: %d ms remain after connect", timeout_ms); 773 774 /* 775 * If we successfully made the connection, load the host private key 776 * in case we will need it later for combined rsa-rhosts 777 * authentication. This must be done before releasing extra 778 * privileges, because the file is only readable by root. 779 * If we cannot access the private keys, load the public keys 780 * instead and try to execute the ssh-keysign helper instead. 781 */ 782 sensitive_data.nkeys = 0; 783 sensitive_data.keys = NULL; 784 sensitive_data.external_keysign = 0; 785 if (options.rhosts_rsa_authentication || 786 options.hostbased_authentication) { 787 sensitive_data.nkeys = 5; 788 sensitive_data.keys = xcalloc(sensitive_data.nkeys, 789 sizeof(Key)); 790 791 PRIV_START; 792 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, 793 _PATH_HOST_KEY_FILE, "", NULL, NULL); 794 sensitive_data.keys[1] = key_load_private_cert(KEY_DSA, 795 _PATH_HOST_DSA_KEY_FILE, "", NULL); 796 sensitive_data.keys[2] = key_load_private_cert(KEY_RSA, 797 _PATH_HOST_RSA_KEY_FILE, "", NULL); 798 sensitive_data.keys[3] = key_load_private_type(KEY_DSA, 799 _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); 800 sensitive_data.keys[4] = key_load_private_type(KEY_RSA, 801 _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); 802 PRIV_END; 803 804 if (options.hostbased_authentication == 1 && 805 sensitive_data.keys[0] == NULL && 806 sensitive_data.keys[3] == NULL && 807 sensitive_data.keys[4] == NULL) { 808 sensitive_data.keys[1] = key_load_cert( 809 _PATH_HOST_DSA_KEY_FILE); 810 sensitive_data.keys[2] = key_load_cert( 811 _PATH_HOST_RSA_KEY_FILE); 812 sensitive_data.keys[3] = key_load_public( 813 _PATH_HOST_DSA_KEY_FILE, NULL); 814 sensitive_data.keys[4] = key_load_public( 815 _PATH_HOST_RSA_KEY_FILE, NULL); 816 sensitive_data.external_keysign = 1; 817 } 818 } 819 /* 820 * Get rid of any extra privileges that we may have. We will no 821 * longer need them. Also, extra privileges could make it very hard 822 * to read identity files and other non-world-readable files from the 823 * user's home directory if it happens to be on a NFS volume where 824 * root is mapped to nobody. 825 */ 826 if (original_effective_uid == 0) { 827 PRIV_START; 828 permanently_set_uid(pw); 829 } 830 831 /* 832 * Now that we are back to our own permissions, create ~/.ssh 833 * directory if it doesn't already exist. 834 */ 835 r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, 836 strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); 837 if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) 838 if (mkdir(buf, 0700) < 0) 839 error("Could not create directory '%.200s'.", buf); 840 841 /* load options.identity_files */ 842 load_public_identity_files(); 843 844 /* Expand ~ in known host file names. */ 845 /* XXX mem-leaks: */ 846 options.system_hostfile = 847 tilde_expand_filename(options.system_hostfile, original_real_uid); 848 options.user_hostfile = 849 tilde_expand_filename(options.user_hostfile, original_real_uid); 850 options.system_hostfile2 = 851 tilde_expand_filename(options.system_hostfile2, original_real_uid); 852 options.user_hostfile2 = 853 tilde_expand_filename(options.user_hostfile2, original_real_uid); 854 855 signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ 856 857 /* Log into the remote system. Never returns if the login fails. */ 858 ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, 859 pw, timeout_ms); 860 861 if (packet_connection_is_on_socket()) { 862 verbose("Authenticated to %s ([%s]:%d).", host, 863 get_remote_ipaddr(), get_remote_port()); 864 } else { 865 verbose("Authenticated to %s (via proxy).", host); 866 } 867 868 /* We no longer need the private host keys. Clear them now. */ 869 if (sensitive_data.nkeys != 0) { 870 for (i = 0; i < sensitive_data.nkeys; i++) { 871 if (sensitive_data.keys[i] != NULL) { 872 /* Destroys contents safely */ 873 debug3("clear hostkey %d", i); 874 key_free(sensitive_data.keys[i]); 875 sensitive_data.keys[i] = NULL; 876 } 877 } 878 xfree(sensitive_data.keys); 879 } 880 for (i = 0; i < options.num_identity_files; i++) { 881 if (options.identity_files[i]) { 882 xfree(options.identity_files[i]); 883 options.identity_files[i] = NULL; 884 } 885 if (options.identity_keys[i]) { 886 key_free(options.identity_keys[i]); 887 options.identity_keys[i] = NULL; 888 } 889 } 890 891 exit_status = compat20 ? ssh_session2() : ssh_session(); 892 packet_close(); 893 894 if (options.control_path != NULL && muxserver_sock != -1) 895 unlink(options.control_path); 896 897 /* 898 * Send SIGHUP to proxy command if used. We don't wait() in 899 * case it hangs and instead rely on init to reap the child 900 */ 901 if (proxy_command_pid > 1) 902 kill(proxy_command_pid, SIGHUP); 903 904 return exit_status; 905 } 906 907 static void 908 control_persist_detach(void) 909 { 910 pid_t pid; 911 int devnull; 912 913 debug("%s: backgrounding master process", __func__); 914 915 /* 916 * master (current process) into the background, and make the 917 * foreground process a client of the backgrounded master. 918 */ 919 switch ((pid = fork())) { 920 case -1: 921 fatal("%s: fork: %s", __func__, strerror(errno)); 922 case 0: 923 /* Child: master process continues mainloop */ 924 break; 925 default: 926 /* Parent: set up mux slave to connect to backgrounded master */ 927 debug2("%s: background process is %ld", __func__, (long)pid); 928 stdin_null_flag = ostdin_null_flag; 929 no_shell_flag = ono_shell_flag; 930 no_tty_flag = ono_tty_flag; 931 tty_flag = otty_flag; 932 close(muxserver_sock); 933 muxserver_sock = -1; 934 muxclient(options.control_path); 935 /* muxclient() doesn't return on success. */ 936 fatal("Failed to connect to new control master"); 937 } 938 if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { 939 error("%s: open(\"/dev/null\"): %s", __func__, 940 strerror(errno)); 941 } else { 942 if (dup2(devnull, STDIN_FILENO) == -1 || 943 dup2(devnull, STDOUT_FILENO) == -1) 944 error("%s: dup2: %s", __func__, strerror(errno)); 945 if (devnull > STDERR_FILENO) 946 close(devnull); 947 } 948 } 949 950 /* Do fork() after authentication. Used by "ssh -f" */ 951 static void 952 fork_postauth(void) 953 { 954 if (need_controlpersist_detach) 955 control_persist_detach(); 956 debug("forking to background"); 957 fork_after_authentication_flag = 0; 958 if (daemon(1, 1) < 0) 959 fatal("daemon() failed: %.200s", strerror(errno)); 960 } 961 962 /* Callback for remote forward global requests */ 963 static void 964 ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt) 965 { 966 Forward *rfwd = (Forward *)ctxt; 967 968 /* XXX verbose() on failure? */ 969 debug("remote forward %s for: listen %d, connect %s:%d", 970 type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", 971 rfwd->listen_port, rfwd->connect_host, rfwd->connect_port); 972 if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) { 973 rfwd->allocated_port = packet_get_int(); 974 logit("Allocated port %u for remote forward to %s:%d", 975 rfwd->allocated_port, 976 rfwd->connect_host, rfwd->connect_port); 977 } 978 979 if (type == SSH2_MSG_REQUEST_FAILURE) { 980 if (options.exit_on_forward_failure) 981 fatal("Error: remote port forwarding failed for " 982 "listen port %d", rfwd->listen_port); 983 else 984 logit("Warning: remote port forwarding failed for " 985 "listen port %d", rfwd->listen_port); 986 } 987 if (++remote_forward_confirms_received == options.num_remote_forwards) { 988 debug("All remote forwarding requests processed"); 989 if (fork_after_authentication_flag) 990 fork_postauth(); 991 } 992 } 993 994 static void 995 client_cleanup_stdio_fwd(int id, void *arg) 996 { 997 debug("stdio forwarding: done"); 998 cleanup_exit(0); 999 } 1000 1001 static int 1002 client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect) 1003 { 1004 Channel *c; 1005 int in, out; 1006 1007 debug3("client_setup_stdio_fwd %s:%d", host_to_connect, 1008 port_to_connect); 1009 1010 in = dup(STDIN_FILENO); 1011 out = dup(STDOUT_FILENO); 1012 if (in < 0 || out < 0) 1013 fatal("channel_connect_stdio_fwd: dup() in/out failed"); 1014 1015 if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect, 1016 in, out)) == NULL) 1017 return 0; 1018 channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0); 1019 return 1; 1020 } 1021 1022 static void 1023 ssh_init_forwarding(void) 1024 { 1025 int success = 0; 1026 int i; 1027 1028 if (stdio_forward_host != NULL) { 1029 if (!compat20) { 1030 fatal("stdio forwarding require Protocol 2"); 1031 } 1032 if (!client_setup_stdio_fwd(stdio_forward_host, 1033 stdio_forward_port)) 1034 fatal("Failed to connect in stdio forward mode."); 1035 } 1036 1037 /* Initiate local TCP/IP port forwardings. */ 1038 for (i = 0; i < options.num_local_forwards; i++) { 1039 debug("Local connections to %.200s:%d forwarded to remote " 1040 "address %.200s:%d", 1041 (options.local_forwards[i].listen_host == NULL) ? 1042 (options.gateway_ports ? "*" : "LOCALHOST") : 1043 options.local_forwards[i].listen_host, 1044 options.local_forwards[i].listen_port, 1045 options.local_forwards[i].connect_host, 1046 options.local_forwards[i].connect_port); 1047 success += channel_setup_local_fwd_listener( 1048 options.local_forwards[i].listen_host, 1049 options.local_forwards[i].listen_port, 1050 options.local_forwards[i].connect_host, 1051 options.local_forwards[i].connect_port, 1052 options.gateway_ports); 1053 } 1054 if (i > 0 && success != i && options.exit_on_forward_failure) 1055 fatal("Could not request local forwarding."); 1056 if (i > 0 && success == 0) 1057 error("Could not request local forwarding."); 1058 1059 /* Initiate remote TCP/IP port forwardings. */ 1060 for (i = 0; i < options.num_remote_forwards; i++) { 1061 debug("Remote connections from %.200s:%d forwarded to " 1062 "local address %.200s:%d", 1063 (options.remote_forwards[i].listen_host == NULL) ? 1064 "LOCALHOST" : options.remote_forwards[i].listen_host, 1065 options.remote_forwards[i].listen_port, 1066 options.remote_forwards[i].connect_host, 1067 options.remote_forwards[i].connect_port); 1068 if (channel_request_remote_forwarding( 1069 options.remote_forwards[i].listen_host, 1070 options.remote_forwards[i].listen_port, 1071 options.remote_forwards[i].connect_host, 1072 options.remote_forwards[i].connect_port) < 0) { 1073 if (options.exit_on_forward_failure) 1074 fatal("Could not request remote forwarding."); 1075 else 1076 logit("Warning: Could not request remote " 1077 "forwarding."); 1078 } 1079 client_register_global_confirm(ssh_confirm_remote_forward, 1080 &options.remote_forwards[i]); 1081 } 1082 1083 /* Initiate tunnel forwarding. */ 1084 if (options.tun_open != SSH_TUNMODE_NO) { 1085 if (client_request_tun_fwd(options.tun_open, 1086 options.tun_local, options.tun_remote) == -1) { 1087 if (options.exit_on_forward_failure) 1088 fatal("Could not request tunnel forwarding."); 1089 else 1090 error("Could not request tunnel forwarding."); 1091 } 1092 } 1093 } 1094 1095 static void 1096 check_agent_present(void) 1097 { 1098 if (options.forward_agent) { 1099 /* Clear agent forwarding if we don't have an agent. */ 1100 if (!ssh_agent_present()) 1101 options.forward_agent = 0; 1102 } 1103 } 1104 1105 static int 1106 ssh_session(void) 1107 { 1108 int type; 1109 int interactive = 0; 1110 int have_tty = 0; 1111 struct winsize ws; 1112 char *cp; 1113 const char *display; 1114 1115 /* Enable compression if requested. */ 1116 if (options.compression) { 1117 debug("Requesting compression at level %d.", 1118 options.compression_level); 1119 1120 if (options.compression_level < 1 || 1121 options.compression_level > 9) 1122 fatal("Compression level must be from 1 (fast) to " 1123 "9 (slow, best)."); 1124 1125 /* Send the request. */ 1126 packet_start(SSH_CMSG_REQUEST_COMPRESSION); 1127 packet_put_int(options.compression_level); 1128 packet_send(); 1129 packet_write_wait(); 1130 type = packet_read(); 1131 if (type == SSH_SMSG_SUCCESS) 1132 packet_start_compression(options.compression_level); 1133 else if (type == SSH_SMSG_FAILURE) 1134 logit("Warning: Remote host refused compression."); 1135 else 1136 packet_disconnect("Protocol error waiting for " 1137 "compression response."); 1138 } 1139 /* Allocate a pseudo tty if appropriate. */ 1140 if (tty_flag) { 1141 debug("Requesting pty."); 1142 1143 /* Start the packet. */ 1144 packet_start(SSH_CMSG_REQUEST_PTY); 1145 1146 /* Store TERM in the packet. There is no limit on the 1147 length of the string. */ 1148 cp = getenv("TERM"); 1149 if (!cp) 1150 cp = ""; 1151 packet_put_cstring(cp); 1152 1153 /* Store window size in the packet. */ 1154 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) 1155 memset(&ws, 0, sizeof(ws)); 1156 packet_put_int((u_int)ws.ws_row); 1157 packet_put_int((u_int)ws.ws_col); 1158 packet_put_int((u_int)ws.ws_xpixel); 1159 packet_put_int((u_int)ws.ws_ypixel); 1160 1161 /* Store tty modes in the packet. */ 1162 tty_make_modes(fileno(stdin), NULL); 1163 1164 /* Send the packet, and wait for it to leave. */ 1165 packet_send(); 1166 packet_write_wait(); 1167 1168 /* Read response from the server. */ 1169 type = packet_read(); 1170 if (type == SSH_SMSG_SUCCESS) { 1171 interactive = 1; 1172 have_tty = 1; 1173 } else if (type == SSH_SMSG_FAILURE) 1174 logit("Warning: Remote host failed or refused to " 1175 "allocate a pseudo tty."); 1176 else 1177 packet_disconnect("Protocol error waiting for pty " 1178 "request response."); 1179 } 1180 /* Request X11 forwarding if enabled and DISPLAY is set. */ 1181 display = getenv("DISPLAY"); 1182 if (options.forward_x11 && display != NULL) { 1183 char *proto, *data; 1184 /* Get reasonable local authentication information. */ 1185 client_x11_get_proto(display, options.xauth_location, 1186 options.forward_x11_trusted, 1187 options.forward_x11_timeout, 1188 &proto, &data); 1189 /* Request forwarding with authentication spoofing. */ 1190 debug("Requesting X11 forwarding with authentication " 1191 "spoofing."); 1192 x11_request_forwarding_with_spoofing(0, display, proto, data); 1193 1194 /* Read response from the server. */ 1195 type = packet_read(); 1196 if (type == SSH_SMSG_SUCCESS) { 1197 interactive = 1; 1198 } else if (type == SSH_SMSG_FAILURE) { 1199 logit("Warning: Remote host denied X11 forwarding."); 1200 } else { 1201 packet_disconnect("Protocol error waiting for X11 " 1202 "forwarding"); 1203 } 1204 } 1205 /* Tell the packet module whether this is an interactive session. */ 1206 packet_set_interactive(interactive); 1207 1208 /* Request authentication agent forwarding if appropriate. */ 1209 check_agent_present(); 1210 1211 if (options.forward_agent) { 1212 debug("Requesting authentication agent forwarding."); 1213 auth_request_forwarding(); 1214 1215 /* Read response from the server. */ 1216 type = packet_read(); 1217 packet_check_eom(); 1218 if (type != SSH_SMSG_SUCCESS) 1219 logit("Warning: Remote host denied authentication agent forwarding."); 1220 } 1221 1222 /* Initiate port forwardings. */ 1223 ssh_init_forwarding(); 1224 1225 /* Execute a local command */ 1226 if (options.local_command != NULL && 1227 options.permit_local_command) 1228 ssh_local_cmd(options.local_command); 1229 1230 /* 1231 * If requested and we are not interested in replies to remote 1232 * forwarding requests, then let ssh continue in the background. 1233 */ 1234 if (fork_after_authentication_flag) { 1235 if (options.exit_on_forward_failure && 1236 options.num_remote_forwards > 0) { 1237 debug("deferring postauth fork until remote forward " 1238 "confirmation received"); 1239 } else 1240 fork_postauth(); 1241 } 1242 1243 /* 1244 * If a command was specified on the command line, execute the 1245 * command now. Otherwise request the server to start a shell. 1246 */ 1247 if (buffer_len(&command) > 0) { 1248 int len = buffer_len(&command); 1249 if (len > 900) 1250 len = 900; 1251 debug("Sending command: %.*s", len, 1252 (u_char *)buffer_ptr(&command)); 1253 packet_start(SSH_CMSG_EXEC_CMD); 1254 packet_put_string(buffer_ptr(&command), buffer_len(&command)); 1255 packet_send(); 1256 packet_write_wait(); 1257 } else { 1258 debug("Requesting shell."); 1259 packet_start(SSH_CMSG_EXEC_SHELL); 1260 packet_send(); 1261 packet_write_wait(); 1262 } 1263 1264 /* Enter the interactive session. */ 1265 return client_loop(have_tty, tty_flag ? 1266 options.escape_char : SSH_ESCAPECHAR_NONE, 0); 1267 } 1268 1269 /* request pty/x11/agent/tcpfwd/shell for channel */ 1270 static void 1271 ssh_session2_setup(int id, int success, void *arg) 1272 { 1273 extern char **environ; 1274 const char *display; 1275 int interactive = tty_flag; 1276 1277 if (!success) 1278 return; /* No need for error message, channels code sens one */ 1279 1280 display = getenv("DISPLAY"); 1281 if (options.forward_x11 && display != NULL) { 1282 char *proto, *data; 1283 /* Get reasonable local authentication information. */ 1284 client_x11_get_proto(display, options.xauth_location, 1285 options.forward_x11_trusted, 1286 options.forward_x11_timeout, &proto, &data); 1287 /* Request forwarding with authentication spoofing. */ 1288 debug("Requesting X11 forwarding with authentication " 1289 "spoofing."); 1290 x11_request_forwarding_with_spoofing(id, display, proto, data); 1291 interactive = 1; 1292 /* XXX wait for reply */ 1293 } 1294 1295 check_agent_present(); 1296 if (options.forward_agent) { 1297 debug("Requesting authentication agent forwarding."); 1298 channel_request_start(id, "auth-agent-req@openssh.com", 0); 1299 packet_send(); 1300 } 1301 1302 client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), 1303 NULL, fileno(stdin), &command, environ); 1304 1305 packet_set_interactive(interactive); 1306 } 1307 1308 /* open new channel for a session */ 1309 static int 1310 ssh_session2_open(void) 1311 { 1312 Channel *c; 1313 int window, packetmax, in, out, err; 1314 int sock; 1315 int socksize; 1316 int socksizelen = sizeof(int); 1317 1318 if (stdin_null_flag) { 1319 in = open(_PATH_DEVNULL, O_RDONLY); 1320 } else { 1321 in = dup(STDIN_FILENO); 1322 } 1323 out = dup(STDOUT_FILENO); 1324 err = dup(STDERR_FILENO); 1325 1326 if (in < 0 || out < 0 || err < 0) 1327 fatal("dup() in/out/err failed"); 1328 1329 /* enable nonblocking unless tty */ 1330 if (!isatty(in)) 1331 set_nonblock(in); 1332 if (!isatty(out)) 1333 set_nonblock(out); 1334 if (!isatty(err)) 1335 set_nonblock(err); 1336 1337 /* we need to check to see if what they want to do about buffer */ 1338 /* sizes here. In a hpn to nonhpn connection we want to limit */ 1339 /* the window size to something reasonable in case the far side */ 1340 /* has the large window bug. In hpn to hpn connection we want to */ 1341 /* use the max window size but allow the user to override it */ 1342 /* lastly if they disabled hpn then use the ssh std window size */ 1343 1344 /* so why don't we just do a getsockopt() here and set the */ 1345 /* ssh window to that? In the case of a autotuning receive */ 1346 /* window the window would get stuck at the initial buffer */ 1347 /* size generally less than 96k. Therefore we need to set the */ 1348 /* maximum ssh window size to the maximum hpn buffer size */ 1349 /* unless the user has specifically set the tcprcvbufpoll */ 1350 /* to no. In which case we *can* just set the window to the */ 1351 /* minimum of the hpn buffer size and tcp receive buffer size */ 1352 1353 if (tty_flag) 1354 options.hpn_buffer_size = CHAN_SES_WINDOW_DEFAULT; 1355 else 1356 options.hpn_buffer_size = 2*1024*1024; 1357 1358 if (datafellows & SSH_BUG_LARGEWINDOW) 1359 { 1360 debug("HPN to Non-HPN Connection"); 1361 } 1362 else 1363 { 1364 if (options.tcp_rcv_buf_poll <= 0) 1365 { 1366 sock = socket(AF_INET, SOCK_STREAM, 0); 1367 getsockopt(sock, SOL_SOCKET, SO_RCVBUF, 1368 &socksize, &socksizelen); 1369 close(sock); 1370 debug("socksize %d", socksize); 1371 options.hpn_buffer_size = socksize; 1372 debug ("HPNBufferSize set to TCP RWIN: %d", options.hpn_buffer_size); 1373 } 1374 else 1375 { 1376 if (options.tcp_rcv_buf > 0) 1377 { 1378 /*create a socket but don't connect it */ 1379 /* we use that the get the rcv socket size */ 1380 sock = socket(AF_INET, SOCK_STREAM, 0); 1381 /* if they are using the tcp_rcv_buf option */ 1382 /* attempt to set the buffer size to that */ 1383 if (options.tcp_rcv_buf) 1384 setsockopt(sock, SOL_SOCKET, SO_RCVBUF, (void *)&options.tcp_rcv_buf, 1385 sizeof(options.tcp_rcv_buf)); 1386 getsockopt(sock, SOL_SOCKET, SO_RCVBUF, 1387 &socksize, &socksizelen); 1388 close(sock); 1389 debug("socksize %d", socksize); 1390 options.hpn_buffer_size = socksize; 1391 debug ("HPNBufferSize set to user TCPRcvBuf: %d", options.hpn_buffer_size); 1392 } 1393 } 1394 1395 } 1396 1397 debug("Final hpn_buffer_size = %d", options.hpn_buffer_size); 1398 1399 window = options.hpn_buffer_size; 1400 1401 channel_set_hpn(options.hpn_disabled, options.hpn_buffer_size); 1402 1403 packetmax = CHAN_SES_PACKET_DEFAULT; 1404 if (tty_flag) { 1405 window = 4*CHAN_SES_PACKET_DEFAULT; 1406 window >>= 1; 1407 packetmax >>= 1; 1408 } 1409 c = channel_new( 1410 "session", SSH_CHANNEL_OPENING, in, out, err, 1411 window, packetmax, CHAN_EXTENDED_WRITE, 1412 "client-session", /*nonblock*/0); 1413 if ((options.tcp_rcv_buf_poll > 0) && (!options.hpn_disabled)) { 1414 c->dynamic_window = 1; 1415 debug ("Enabled Dynamic Window Scaling\n"); 1416 } 1417 debug3("ssh_session2_open: channel_new: %d", c->self); 1418 1419 channel_send_open(c->self); 1420 if (!no_shell_flag) 1421 channel_register_open_confirm(c->self, 1422 ssh_session2_setup, NULL); 1423 1424 return c->self; 1425 } 1426 1427 static int 1428 ssh_session2(void) 1429 { 1430 int id = -1; 1431 1432 /* XXX should be pre-session */ 1433 ssh_init_forwarding(); 1434 1435 /* Start listening for multiplex clients */ 1436 muxserver_listen(); 1437 1438 /* 1439 * If we are in control persist mode, then prepare to background 1440 * ourselves and have a foreground client attach as a control 1441 * slave. NB. we must save copies of the flags that we override for 1442 * the backgrounding, since we defer attachment of the slave until 1443 * after the connection is fully established (in particular, 1444 * async rfwd replies have been received for ExitOnForwardFailure). 1445 */ 1446 if (options.control_persist && muxserver_sock != -1) { 1447 ostdin_null_flag = stdin_null_flag; 1448 ono_shell_flag = no_shell_flag; 1449 ono_tty_flag = no_tty_flag; 1450 otty_flag = tty_flag; 1451 stdin_null_flag = 1; 1452 no_shell_flag = 1; 1453 no_tty_flag = 1; 1454 tty_flag = 0; 1455 if (!fork_after_authentication_flag) 1456 need_controlpersist_detach = 1; 1457 fork_after_authentication_flag = 1; 1458 } 1459 1460 if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) 1461 id = ssh_session2_open(); 1462 1463 /* If we don't expect to open a new session, then disallow it */ 1464 if (options.control_master == SSHCTL_MASTER_NO && 1465 (datafellows & SSH_NEW_OPENSSH)) { 1466 debug("Requesting no-more-sessions@openssh.com"); 1467 packet_start(SSH2_MSG_GLOBAL_REQUEST); 1468 packet_put_cstring("no-more-sessions@openssh.com"); 1469 packet_put_char(0); 1470 packet_send(); 1471 } 1472 1473 /* Execute a local command */ 1474 if (options.local_command != NULL && 1475 options.permit_local_command) 1476 ssh_local_cmd(options.local_command); 1477 1478 /* 1479 * If requested and we are not interested in replies to remote 1480 * forwarding requests, then let ssh continue in the background. 1481 */ 1482 if (fork_after_authentication_flag) { 1483 if (options.exit_on_forward_failure && 1484 options.num_remote_forwards > 0) { 1485 debug("deferring postauth fork until remote forward " 1486 "confirmation received"); 1487 } else 1488 fork_postauth(); 1489 } 1490 1491 if (options.use_roaming) 1492 request_roaming(); 1493 1494 return client_loop(tty_flag, tty_flag ? 1495 options.escape_char : SSH_ESCAPECHAR_NONE, id); 1496 } 1497 1498 static void 1499 load_public_identity_files(void) 1500 { 1501 char *filename, *cp, thishost[NI_MAXHOST]; 1502 char *pwdir = NULL, *pwname = NULL; 1503 int i = 0; 1504 Key *public; 1505 struct passwd *pw; 1506 u_int n_ids; 1507 char *identity_files[SSH_MAX_IDENTITY_FILES]; 1508 Key *identity_keys[SSH_MAX_IDENTITY_FILES]; 1509 #ifdef ENABLE_PKCS11 1510 Key **keys; 1511 int nkeys; 1512 #endif /* PKCS11 */ 1513 1514 n_ids = 0; 1515 bzero(identity_files, sizeof(identity_files)); 1516 bzero(identity_keys, sizeof(identity_keys)); 1517 1518 #ifdef ENABLE_PKCS11 1519 if (options.pkcs11_provider != NULL && 1520 options.num_identity_files < SSH_MAX_IDENTITY_FILES && 1521 (pkcs11_init(!options.batch_mode) == 0) && 1522 (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, 1523 &keys)) > 0) { 1524 for (i = 0; i < nkeys; i++) { 1525 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1526 key_free(keys[i]); 1527 continue; 1528 } 1529 identity_keys[n_ids] = keys[i]; 1530 identity_files[n_ids] = 1531 xstrdup(options.pkcs11_provider); /* XXX */ 1532 n_ids++; 1533 } 1534 xfree(keys); 1535 } 1536 #endif /* ENABLE_PKCS11 */ 1537 if ((pw = getpwuid(original_real_uid)) == NULL) 1538 fatal("load_public_identity_files: getpwuid failed"); 1539 pwname = xstrdup(pw->pw_name); 1540 pwdir = xstrdup(pw->pw_dir); 1541 if (gethostname(thishost, sizeof(thishost)) == -1) 1542 fatal("load_public_identity_files: gethostname: %s", 1543 strerror(errno)); 1544 for (i = 0; i < options.num_identity_files; i++) { 1545 if (n_ids >= SSH_MAX_IDENTITY_FILES) { 1546 xfree(options.identity_files[i]); 1547 continue; 1548 } 1549 cp = tilde_expand_filename(options.identity_files[i], 1550 original_real_uid); 1551 filename = percent_expand(cp, "d", pwdir, 1552 "u", pwname, "l", thishost, "h", host, 1553 "r", options.user, (char *)NULL); 1554 xfree(cp); 1555 public = key_load_public(filename, NULL); 1556 debug("identity file %s type %d", filename, 1557 public ? public->type : -1); 1558 xfree(options.identity_files[i]); 1559 identity_files[n_ids] = filename; 1560 identity_keys[n_ids] = public; 1561 1562 if (++n_ids >= SSH_MAX_IDENTITY_FILES) 1563 continue; 1564 1565 /* Try to add the certificate variant too */ 1566 xasprintf(&cp, "%s-cert", filename); 1567 public = key_load_public(cp, NULL); 1568 debug("identity file %s type %d", cp, 1569 public ? public->type : -1); 1570 if (public == NULL) { 1571 xfree(cp); 1572 continue; 1573 } 1574 if (!key_is_cert(public)) { 1575 debug("%s: key %s type %s is not a certificate", 1576 __func__, cp, key_type(public)); 1577 key_free(public); 1578 xfree(cp); 1579 continue; 1580 } 1581 identity_keys[n_ids] = public; 1582 /* point to the original path, most likely the private key */ 1583 identity_files[n_ids] = xstrdup(filename); 1584 n_ids++; 1585 } 1586 options.num_identity_files = n_ids; 1587 memcpy(options.identity_files, identity_files, sizeof(identity_files)); 1588 memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); 1589 1590 bzero(pwname, strlen(pwname)); 1591 xfree(pwname); 1592 bzero(pwdir, strlen(pwdir)); 1593 xfree(pwdir); 1594 } 1595