crypto/openssh/ssh.c

   1 /* $OpenBSD: ssh.c,v 1.324 2009/02/12 03:00:56 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/socket.h>
  52
  53 #include <ctype.h>
  54 #include <errno.h>
  55 #include <fcntl.h>
  56 #include <netdb.h>
  57 #ifdef HAVE_PATHS_H
  58 #include <paths.h>
  59 #endif
  60 #include <pwd.h>
  61 #include <signal.h>
  62 #include <stdarg.h>
  63 #include <stddef.h>
  64 #include <stdio.h>
  65 #include <stdlib.h>
  66 #include <string.h>
  67 #include <unistd.h>
  68
  69 #include <netinet/in.h>
  70 #include <arpa/inet.h>
  71
  72 #include <openssl/evp.h>
  73 #include <openssl/err.h>
  74 #include "openbsd-compat/openssl-compat.h"
  75 #include "openbsd-compat/sys-queue.h"
  76
  77 #include "xmalloc.h"
  78 #include "ssh.h"
  79 #include "ssh1.h"
  80 #include "ssh2.h"
  81 #include "compat.h"
  82 #include "cipher.h"
  83 #include "packet.h"
  84 #include "buffer.h"
  85 #include "channels.h"
  86 #include "key.h"
  87 #include "authfd.h"
  88 #include "authfile.h"
  89 #include "pathnames.h"
  90 #include "dispatch.h"
  91 #include "clientloop.h"
  92 #include "log.h"
  93 #include "readconf.h"
  94 #include "sshconnect.h"
  95 #include "misc.h"
  96 #include "kex.h"
  97 #include "mac.h"
  98 #include "sshpty.h"
  99 #include "match.h"
 100 #include "msg.h"
 101 #include "uidswap.h"
 102 #include "version.h"
 103
 104 #ifdef SMARTCARD
 105 #include "scard.h"
 106 #endif
 107
 108 extern char *__progname;
 109
 110 /* Flag indicating whether debug mode is on.  May be set on the command line. */
 111 int debug_flag = 0;
 112
 113 /* Flag indicating whether a tty should be allocated */
 114 int tty_flag = 0;
 115 int no_tty_flag = 0;
 116 int force_tty_flag = 0;
 117
 118 /* don't exec a shell */
 119 int no_shell_flag = 0;
 120
 121 /*
 122  * Flag indicating that nothing should be read from stdin.  This can be set
 123  * on the command line.
 124  */
 125 int stdin_null_flag = 0;
 126
 127 /*
 128  * Flag indicating that ssh should fork after authentication.  This is useful
 129  * so that the passphrase can be entered manually, and then ssh goes to the
 130  * background.
 131  */
 132 int fork_after_authentication_flag = 0;
 133
 134 /*
 135  * General data structure for command line options and options configurable
 136  * in configuration files.  See readconf.h.
 137  */
 138 Options options;
 139
 140 /* optional user configfile */
 141 char *config = NULL;
 142
 143 /*
 144  * Name of the host we are connecting to.  This is the name given on the
 145  * command line, or the HostName specified for the user-supplied name in a
 146  * configuration file.
 147  */
 148 char *host;
 149
 150 /* socket address the host resolves to */
 151 struct sockaddr_storage hostaddr;
 152
 153 /* Private host keys. */
 154 Sensitive sensitive_data;
 155
 156 /* Original real UID. */
 157 uid_t original_real_uid;
 158 uid_t original_effective_uid;
 159
 160 /* command to be executed */
 161 Buffer command;
 162
 163 /* Should we execute a command or invoke a subsystem? */
 164 int subsystem_flag = 0;
 165
 166 /* # of replies received for global requests */
 167 static int remote_forward_confirms_received = 0;
 168
 169 /* pid of proxycommand child process */
 170 pid_t proxy_command_pid = 0;
 171
 172 /* mux.c */
 173 extern int muxserver_sock;
 174 extern u_int muxclient_command;
 175
 176 /* Prints a help message to the user.  This function never returns. */
 177
 178 static void
 179 usage(void)
 180 {
 181         fprintf(stderr,
 182 "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
 183 "           [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
 184 "           [-i identity_file] [-L [bind_address:]port:host:hostport]\n"
 185 "           [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
 186 "           [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
 187 "           [-w local_tun[:remote_tun]] [user@]hostname [command]\n"
 188         );
 189         exit(255);
 190 }
 191
 192 static int ssh_session(void);
 193 static int ssh_session2(void);
 194 static void load_public_identity_files(void);
 195
 196 /* from muxclient.c */
 197 void muxclient(const char *);
 198 void muxserver_listen(void);
 199
 200 /*
 201  * Main program for the ssh client.
 202  */
 203 int
 204 main(int ac, char **av)
 205 {
 206         int i, opt, exit_status, use_syslog;
 207         char *p, *cp, *line, buf[256];
 208         struct stat st;
 209         struct passwd *pw;
 210         int dummy, timeout_ms;
 211         extern int optind, optreset;
 212         extern char *optarg;
 213         struct servent *sp;
 214         Forward fwd;
 215
 216         /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
 217         sanitise_stdfd();
 218
 219         __progname = ssh_get_progname(av[0]);
 220         init_rng();
 221
 222         /*
 223          * Save the original real uid.  It will be needed later (uid-swapping
 224          * may clobber the real uid).
 225          */
 226         original_real_uid = getuid();
 227         original_effective_uid = geteuid();
 228
 229         /*
 230          * Use uid-swapping to give up root privileges for the duration of
 231          * option processing.  We will re-instantiate the rights when we are
 232          * ready to create the privileged port, and will permanently drop
 233          * them when the port has been created (actually, when the connection
 234          * has been made, as we may need to create the port several times).
 235          */
 236         PRIV_END;
 237
 238 #ifdef HAVE_SETRLIMIT
 239         /* If we are installed setuid root be careful to not drop core. */
 240         if (original_real_uid != original_effective_uid) {
 241                 struct rlimit rlim;
 242                 rlim.rlim_cur = rlim.rlim_max = 0;
 243                 if (setrlimit(RLIMIT_CORE, &rlim) < 0)
 244                         fatal("setrlimit failed: %.100s", strerror(errno));
 245         }
 246 #endif
 247         /* Get user data. */
 248         pw = getpwuid(original_real_uid);
 249         if (!pw) {
 250                 logit("You don't exist, go away!");
 251                 exit(255);
 252         }
 253         /* Take a copy of the returned structure. */
 254         pw = pwcopy(pw);
 255
 256         /*
 257          * Set our umask to something reasonable, as some files are created
 258          * with the default umask.  This will make them world-readable but
 259          * writable only by the owner, which is ok for all files for which we
 260          * don't set the modes explicitly.
 261          */
 262         umask(022);
 263
 264         /*
 265          * Initialize option structure to indicate that no values have been
 266          * set.
 267          */
 268         initialize_options(&options);
 269
 270         /* Parse command-line arguments. */
 271         host = NULL;
 272         use_syslog = 0;
 273
 274  again:
 275         while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
 276             "ACD:F:I:KL:MNO:PR:S:TVw:XYy")) != -1) {
 277                 switch (opt) {
 278                 case '1':
 279                         options.protocol = SSH_PROTO_1;
 280                         break;
 281                 case '2':
 282                         options.protocol = SSH_PROTO_2;
 283                         break;
 284                 case '4':
 285                         options.address_family = AF_INET;
 286                         break;
 287                 case '6':
 288                         options.address_family = AF_INET6;
 289                         break;
 290                 case 'n':
 291                         stdin_null_flag = 1;
 292                         break;
 293                 case 'f':
 294                         fork_after_authentication_flag = 1;
 295                         stdin_null_flag = 1;
 296                         break;
 297                 case 'x':
 298                         options.forward_x11 = 0;
 299                         break;
 300                 case 'X':
 301                         options.forward_x11 = 1;
 302                         break;
 303                 case 'y':
 304                         use_syslog = 1;
 305                         break;
 306                 case 'Y':
 307                         options.forward_x11 = 1;
 308                         options.forward_x11_trusted = 1;
 309                         break;
 310                 case 'g':
 311                         options.gateway_ports = 1;
 312                         break;
 313                 case 'O':
 314                         if (strcmp(optarg, "check") == 0)
 315                                 muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
 316                         else if (strcmp(optarg, "exit") == 0)
 317                                 muxclient_command = SSHMUX_COMMAND_TERMINATE;
 318                         else
 319                                 fatal("Invalid multiplex command.");
 320                         break;
 321                 case 'P':       /* deprecated */
 322                         options.use_privileged_port = 0;
 323                         break;
 324                 case 'a':
 325                         options.forward_agent = 0;
 326                         break;
 327                 case 'A':
 328                         options.forward_agent = 1;
 329                         break;
 330                 case 'k':
 331                         options.gss_deleg_creds = 0;
 332                         break;
 333                 case 'K':
 334                         options.gss_authentication = 1;
 335                         options.gss_deleg_creds = 1;
 336                         break;
 337                 case 'i':
 338                         if (stat(optarg, &st) < 0) {
 339                                 fprintf(stderr, "Warning: Identity file %s "
 340                                     "not accessible: %s.\n", optarg,
 341                                     strerror(errno));
 342                                 break;
 343                         }
 344                         if (options.num_identity_files >=
 345                             SSH_MAX_IDENTITY_FILES)
 346                                 fatal("Too many identity files specified "
 347                                     "(max %d)", SSH_MAX_IDENTITY_FILES);
 348                         options.identity_files[options.num_identity_files++] =
 349                             xstrdup(optarg);
 350                         break;
 351                 case 'I':
 352 #ifdef SMARTCARD
 353                         options.smartcard_device = xstrdup(optarg);
 354 #else
 355                         fprintf(stderr, "no support for smartcards.\n");
 356 #endif
 357                         break;
 358                 case 't':
 359                         if (tty_flag)
 360                                 force_tty_flag = 1;
 361                         tty_flag = 1;
 362                         break;
 363                 case 'v':
 364                         if (debug_flag == 0) {
 365                                 debug_flag = 1;
 366                                 options.log_level = SYSLOG_LEVEL_DEBUG1;
 367                         } else {
 368                                 if (options.log_level < SYSLOG_LEVEL_DEBUG3)
 369                                         options.log_level++;
 370                                 break;
 371                         }
 372                         /* FALLTHROUGH */
 373                 case 'V':
 374                         fprintf(stderr, "%s, %s\n",
 375                             SSH_RELEASE, SSLeay_version(SSLEAY_VERSION));
 376                         if (opt == 'V')
 377                                 exit(0);
 378                         break;
 379                 case 'w':
 380                         if (options.tun_open == -1)
 381                                 options.tun_open = SSH_TUNMODE_DEFAULT;
 382                         options.tun_local = a2tun(optarg, &options.tun_remote);
 383                         if (options.tun_local == SSH_TUNID_ERR) {
 384                                 fprintf(stderr,
 385                                     "Bad tun device '%s'\n", optarg);
 386                                 exit(255);
 387                         }
 388                         break;
 389                 case 'q':
 390                         options.log_level = SYSLOG_LEVEL_QUIET;
 391                         break;
 392                 case 'e':
 393                         if (optarg[0] == '^' && optarg[2] == 0 &&
 394                             (u_char) optarg[1] >= 64 &&
 395                             (u_char) optarg[1] < 128)
 396                                 options.escape_char = (u_char) optarg[1] & 31;
 397                         else if (strlen(optarg) == 1)
 398                                 options.escape_char = (u_char) optarg[0];
 399                         else if (strcmp(optarg, "none") == 0)
 400                                 options.escape_char = SSH_ESCAPECHAR_NONE;
 401                         else {
 402                                 fprintf(stderr, "Bad escape character '%s'.\n",
 403                                     optarg);
 404                                 exit(255);
 405                         }
 406                         break;
 407                 case 'c':
 408                         if (ciphers_valid(optarg)) {
 409                                 /* SSH2 only */
 410                                 options.ciphers = xstrdup(optarg);
 411                                 options.cipher = SSH_CIPHER_INVALID;
 412                         } else {
 413                                 /* SSH1 only */
 414                                 options.cipher = cipher_number(optarg);
 415                                 if (options.cipher == -1) {
 416                                         fprintf(stderr,
 417                                             "Unknown cipher type '%s'\n",
 418                                             optarg);
 419                                         exit(255);
 420                                 }
 421                                 if (options.cipher == SSH_CIPHER_3DES)
 422                                         options.ciphers = "3des-cbc";
 423                                 else if (options.cipher == SSH_CIPHER_BLOWFISH)
 424                                         options.ciphers = "blowfish-cbc";
 425                                 else
 426                                         options.ciphers = (char *)-1;
 427                         }
 428                         break;
 429                 case 'm':
 430                         if (mac_valid(optarg))
 431                                 options.macs = xstrdup(optarg);
 432                         else {
 433                                 fprintf(stderr, "Unknown mac type '%s'\n",
 434                                     optarg);
 435                                 exit(255);
 436                         }
 437                         break;
 438                 case 'M':
 439                         if (options.control_master == SSHCTL_MASTER_YES)
 440                                 options.control_master = SSHCTL_MASTER_ASK;
 441                         else
 442                                 options.control_master = SSHCTL_MASTER_YES;
 443                         break;
 444                 case 'p':
 445                         options.port = a2port(optarg);
 446                         if (options.port <= 0) {
 447                                 fprintf(stderr, "Bad port '%s'\n", optarg);
 448                                 exit(255);
 449                         }
 450                         break;
 451                 case 'l':
 452                         options.user = optarg;
 453                         break;
 454
 455                 case 'L':
 456                         if (parse_forward(&fwd, optarg, 0, 0))
 457                                 add_local_forward(&options, &fwd);
 458                         else {
 459                                 fprintf(stderr,
 460                                     "Bad local forwarding specification '%s'\n",
 461                                     optarg);
 462                                 exit(255);
 463                         }
 464                         break;
 465
 466                 case 'R':
 467                         if (parse_forward(&fwd, optarg, 0, 1)) {
 468                                 add_remote_forward(&options, &fwd);
 469                         } else {
 470                                 fprintf(stderr,
 471                                     "Bad remote forwarding specification "
 472                                     "'%s'\n", optarg);
 473                                 exit(255);
 474                         }
 475                         break;
 476
 477                 case 'D':
 478                         if (parse_forward(&fwd, optarg, 1, 0)) {
 479                                 add_local_forward(&options, &fwd);
 480                         } else {
 481                                 fprintf(stderr,
 482                                     "Bad dynamic forwarding specification "
 483                                     "'%s'\n", optarg);
 484                                 exit(255);
 485                         }
 486                         break;
 487
 488                 case 'C':
 489                         options.compression = 1;
 490                         break;
 491                 case 'N':
 492                         no_shell_flag = 1;
 493                         no_tty_flag = 1;
 494                         break;
 495                 case 'T':
 496                         no_tty_flag = 1;
 497                         break;
 498                 case 'o':
 499                         dummy = 1;
 500                         line = xstrdup(optarg);
 501                         if (process_config_line(&options, host ? host : "",
 502                             line, "command-line", 0, &dummy) != 0)
 503                                 exit(255);
 504                         xfree(line);
 505                         break;
 506                 case 's':
 507                         subsystem_flag = 1;
 508                         break;
 509                 case 'S':
 510                         if (options.control_path != NULL)
 511                                 free(options.control_path);
 512                         options.control_path = xstrdup(optarg);
 513                         break;
 514                 case 'b':
 515                         options.bind_address = optarg;
 516                         break;
 517                 case 'F':
 518                         config = optarg;
 519                         break;
 520                 default:
 521                         usage();
 522                 }
 523         }
 524
 525         ac -= optind;
 526         av += optind;
 527
 528         if (ac > 0 && !host && **av != '-') {
 529                 if (strrchr(*av, '@')) {
 530                         p = xstrdup(*av);
 531                         cp = strrchr(p, '@');
 532                         if (cp == NULL || cp == p)
 533                                 usage();
 534                         options.user = p;
 535                         *cp = '\0';
 536                         host = ++cp;
 537                 } else
 538                         host = *av;
 539                 if (ac > 1) {
 540                         optind = optreset = 1;
 541                         goto again;
 542                 }
 543                 ac--, av++;
 544         }
 545
 546         /* Check that we got a host name. */
 547         if (!host)
 548                 usage();
 549
 550         SSLeay_add_all_algorithms();
 551         ERR_load_crypto_strings();
 552
 553         /* Initialize the command to execute on remote host. */
 554         buffer_init(&command);
 555
 556         /*
 557          * Save the command to execute on the remote host in a buffer. There
 558          * is no limit on the length of the command, except by the maximum
 559          * packet size.  Also sets the tty flag if there is no command.
 560          */
 561         if (!ac) {
 562                 /* No command specified - execute shell on a tty. */
 563                 tty_flag = 1;
 564                 if (subsystem_flag) {
 565                         fprintf(stderr,
 566                             "You must specify a subsystem to invoke.\n");
 567                         usage();
 568                 }
 569         } else {
 570                 /* A command has been specified.  Store it into the buffer. */
 571                 for (i = 0; i < ac; i++) {
 572                         if (i)
 573                                 buffer_append(&command, " ", 1);
 574                         buffer_append(&command, av[i], strlen(av[i]));
 575                 }
 576         }
 577
 578         /* Cannot fork to background if no command. */
 579         if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
 580             !no_shell_flag)
 581                 fatal("Cannot fork into background without a command "
 582                     "to execute.");
 583
 584         /* Allocate a tty by default if no command specified. */
 585         if (buffer_len(&command) == 0)
 586                 tty_flag = 1;
 587
 588         /* Force no tty */
 589         if (no_tty_flag)
 590                 tty_flag = 0;
 591         /* Do not allocate a tty if stdin is not a tty. */
 592         if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
 593                 if (tty_flag)
 594                         logit("Pseudo-terminal will not be allocated because "
 595                             "stdin is not a terminal.");
 596                 tty_flag = 0;
 597         }
 598
 599         /*
 600          * Initialize "log" output.  Since we are the client all output
 601          * actually goes to stderr.
 602          */
 603         log_init(av[0],
 604             options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
 605             SYSLOG_FACILITY_USER, !use_syslog);
 606
 607         /*
 608          * Read per-user configuration file.  Ignore the system wide config
 609          * file if the user specifies a config file on the command line.
 610          */
 611         if (config != NULL) {
 612                 if (!read_config_file(config, host, &options, 0))
 613                         fatal("Can't open user config file %.100s: "
 614                             "%.100s", config, strerror(errno));
 615         } else {
 616                 snprintf(buf, sizeof buf, "%.100s/%.100s", pw->pw_dir,
 617                     _PATH_SSH_USER_CONFFILE);
 618                 (void)read_config_file(buf, host, &options, 1);
 619
 620                 /* Read systemwide configuration file after use config. */
 621                 (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
 622                     &options, 0);
 623         }
 624
 625         /* Fill configuration defaults. */
 626         fill_default_options(&options);
 627
 628         channel_set_af(options.address_family);
 629
 630         /* reinit */
 631         log_init(av[0], options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
 632
 633         seed_rng();
 634
 635         if (options.user == NULL)
 636                 options.user = xstrdup(pw->pw_name);
 637
 638         /* Get default port if port has not been set. */
 639         if (options.port == 0) {
 640                 sp = getservbyname(SSH_SERVICE_NAME, "tcp");
 641                 options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
 642         }
 643
 644         if (options.local_command != NULL) {
 645                 char thishost[NI_MAXHOST];
 646
 647                 if (gethostname(thishost, sizeof(thishost)) == -1)
 648                         fatal("gethostname: %s", strerror(errno));
 649                 snprintf(buf, sizeof(buf), "%d", options.port);
 650                 debug3("expanding LocalCommand: %s", options.local_command);
 651                 cp = options.local_command;
 652                 options.local_command = percent_expand(cp, "d", pw->pw_dir,
 653                     "h", options.hostname? options.hostname : host,
 654                     "l", thishost, "n", host, "r", options.user, "p", buf,
 655                     "u", pw->pw_name, (char *)NULL);
 656                 debug3("expanded LocalCommand: %s", options.local_command);
 657                 xfree(cp);
 658         }
 659
 660         if (options.hostname != NULL)
 661                 host = options.hostname;
 662
 663         /* Find canonic host name. */
 664         if (strchr(host, '.') == 0) {
 665                 struct addrinfo hints;
 666                 struct addrinfo *ai = NULL;
 667                 int errgai;
 668                 memset(&hints, 0, sizeof(hints));
 669                 hints.ai_family = options.address_family;
 670                 hints.ai_flags = AI_CANONNAME;
 671                 hints.ai_socktype = SOCK_STREAM;
 672                 errgai = getaddrinfo(host, NULL, &hints, &ai);
 673                 if (errgai == 0) {
 674                         if (ai->ai_canonname != NULL)
 675                                 host = xstrdup(ai->ai_canonname);
 676                         freeaddrinfo(ai);
 677                 }
 678         }
 679
 680         /* force lowercase for hostkey matching */
 681         if (options.host_key_alias != NULL) {
 682                 for (p = options.host_key_alias; *p; p++)
 683                         if (isupper(*p))
 684                                 *p = (char)tolower(*p);
 685         }
 686
 687         if (options.proxy_command != NULL &&
 688             strcmp(options.proxy_command, "none") == 0) {
 689                 xfree(options.proxy_command);
 690                 options.proxy_command = NULL;
 691         }
 692         if (options.control_path != NULL &&
 693             strcmp(options.control_path, "none") == 0) {
 694                 xfree(options.control_path);
 695                 options.control_path = NULL;
 696         }
 697
 698         if (options.control_path != NULL) {
 699                 char thishost[NI_MAXHOST];
 700
 701                 if (gethostname(thishost, sizeof(thishost)) == -1)
 702                         fatal("gethostname: %s", strerror(errno));
 703                 snprintf(buf, sizeof(buf), "%d", options.port);
 704                 cp = tilde_expand_filename(options.control_path,
 705                     original_real_uid);
 706                 xfree(options.control_path);
 707                 options.control_path = percent_expand(cp, "p", buf, "h", host,
 708                     "r", options.user, "l", thishost, (char *)NULL);
 709                 xfree(cp);
 710         }
 711         if (muxclient_command != 0 && options.control_path == NULL)
 712                 fatal("No ControlPath specified for \"-O\" command");
 713         if (options.control_path != NULL)
 714                 muxclient(options.control_path);
 715
 716         timeout_ms = options.connection_timeout * 1000;
 717
 718         /* Open a connection to the remote host. */
 719         if (ssh_connect(host, &hostaddr, options.port,
 720             options.address_family, options.connection_attempts, &timeout_ms,
 721             options.tcp_keep_alive,
 722 #ifdef HAVE_CYGWIN
 723             options.use_privileged_port,
 724 #else
 725             original_effective_uid == 0 && options.use_privileged_port,
 726 #endif
 727             options.proxy_command) != 0)
 728                 exit(255);
 729
 730         if (timeout_ms > 0)
 731                 debug3("timeout: %d ms remain after connect", timeout_ms);
 732
 733         /*
 734          * If we successfully made the connection, load the host private key
 735          * in case we will need it later for combined rsa-rhosts
 736          * authentication. This must be done before releasing extra
 737          * privileges, because the file is only readable by root.
 738          * If we cannot access the private keys, load the public keys
 739          * instead and try to execute the ssh-keysign helper instead.
 740          */
 741         sensitive_data.nkeys = 0;
 742         sensitive_data.keys = NULL;
 743         sensitive_data.external_keysign = 0;
 744         if (options.rhosts_rsa_authentication ||
 745             options.hostbased_authentication) {
 746                 sensitive_data.nkeys = 3;
 747                 sensitive_data.keys = xcalloc(sensitive_data.nkeys,
 748                     sizeof(Key));
 749
 750                 PRIV_START;
 751                 sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
 752                     _PATH_HOST_KEY_FILE, "", NULL, NULL);
 753                 sensitive_data.keys[1] = key_load_private_type(KEY_DSA,
 754                     _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
 755                 sensitive_data.keys[2] = key_load_private_type(KEY_RSA,
 756                     _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
 757                 PRIV_END;
 758
 759                 if (options.hostbased_authentication == 1 &&
 760                     sensitive_data.keys[0] == NULL &&
 761                     sensitive_data.keys[1] == NULL &&
 762                     sensitive_data.keys[2] == NULL) {
 763                         sensitive_data.keys[1] = key_load_public(
 764                             _PATH_HOST_DSA_KEY_FILE, NULL);
 765                         sensitive_data.keys[2] = key_load_public(
 766                             _PATH_HOST_RSA_KEY_FILE, NULL);
 767                         sensitive_data.external_keysign = 1;
 768                 }
 769         }
 770         /*
 771          * Get rid of any extra privileges that we may have.  We will no
 772          * longer need them.  Also, extra privileges could make it very hard
 773          * to read identity files and other non-world-readable files from the
 774          * user's home directory if it happens to be on a NFS volume where
 775          * root is mapped to nobody.
 776          */
 777         if (original_effective_uid == 0) {
 778                 PRIV_START;
 779                 permanently_set_uid(pw);
 780         }
 781
 782         /*
 783          * Now that we are back to our own permissions, create ~/.ssh
 784          * directory if it doesn't already exist.
 785          */
 786         snprintf(buf, sizeof buf, "%.100s%s%.100s", pw->pw_dir,
 787             strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
 788         if (stat(buf, &st) < 0)
 789                 if (mkdir(buf, 0700) < 0)
 790                         error("Could not create directory '%.200s'.", buf);
 791
 792         /* load options.identity_files */
 793         load_public_identity_files();
 794
 795         /* Expand ~ in known host file names. */
 796         /* XXX mem-leaks: */
 797         options.system_hostfile =
 798             tilde_expand_filename(options.system_hostfile, original_real_uid);
 799         options.user_hostfile =
 800             tilde_expand_filename(options.user_hostfile, original_real_uid);
 801         options.system_hostfile2 =
 802             tilde_expand_filename(options.system_hostfile2, original_real_uid);
 803         options.user_hostfile2 =
 804             tilde_expand_filename(options.user_hostfile2, original_real_uid);
 805
 806         signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
 807
 808         /* Log into the remote system.  Never returns if the login fails. */
 809         ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
 810             pw, timeout_ms);
 811
 812         /* We no longer need the private host keys.  Clear them now. */
 813         if (sensitive_data.nkeys != 0) {
 814                 for (i = 0; i < sensitive_data.nkeys; i++) {
 815                         if (sensitive_data.keys[i] != NULL) {
 816                                 /* Destroys contents safely */
 817                                 debug3("clear hostkey %d", i);
 818                                 key_free(sensitive_data.keys[i]);
 819                                 sensitive_data.keys[i] = NULL;
 820                         }
 821                 }
 822                 xfree(sensitive_data.keys);
 823         }
 824         for (i = 0; i < options.num_identity_files; i++) {
 825                 if (options.identity_files[i]) {
 826                         xfree(options.identity_files[i]);
 827                         options.identity_files[i] = NULL;
 828                 }
 829                 if (options.identity_keys[i]) {
 830                         key_free(options.identity_keys[i]);
 831                         options.identity_keys[i] = NULL;
 832                 }
 833         }
 834
 835         exit_status = compat20 ? ssh_session2() : ssh_session();
 836         packet_close();
 837
 838         if (options.control_path != NULL && muxserver_sock != -1)
 839                 unlink(options.control_path);
 840
 841         /*
 842          * Send SIGHUP to proxy command if used. We don't wait() in
 843          * case it hangs and instead rely on init to reap the child
 844          */
 845         if (proxy_command_pid > 1)
 846                 kill(proxy_command_pid, SIGHUP);
 847
 848         return exit_status;
 849 }
 850
 851 /* Callback for remote forward global requests */
 852 static void
 853 ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
 854 {
 855         Forward *rfwd = (Forward *)ctxt;
 856
 857         /* XXX verbose() on failure? */
 858         debug("remote forward %s for: listen %d, connect %s:%d",
 859             type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
 860             rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
 861         if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
 862                 logit("Allocated port %u for remote forward to %s:%d",
 863                         packet_get_int(),
 864                         rfwd->connect_host, rfwd->connect_port);
 865         }
 866
 867         if (type == SSH2_MSG_REQUEST_FAILURE) {
 868                 if (options.exit_on_forward_failure)
 869                         fatal("Error: remote port forwarding failed for "
 870                             "listen port %d", rfwd->listen_port);
 871                 else
 872                         logit("Warning: remote port forwarding failed for "
 873                             "listen port %d", rfwd->listen_port);
 874         }
 875         if (++remote_forward_confirms_received == options.num_remote_forwards) {
 876                 debug("All remote forwarding requests processed");
 877                 if (fork_after_authentication_flag) {
 878                         fork_after_authentication_flag = 0;
 879                         if (daemon(1, 1) < 0)
 880                                 fatal("daemon() failed: %.200s",
 881                                     strerror(errno));
 882                 }
 883         }
 884 }
 885
 886 static void
 887 ssh_init_forwarding(void)
 888 {
 889         int success = 0;
 890         int i;
 891
 892         /* Initiate local TCP/IP port forwardings. */
 893         for (i = 0; i < options.num_local_forwards; i++) {
 894                 debug("Local connections to %.200s:%d forwarded to remote "
 895                     "address %.200s:%d",
 896                     (options.local_forwards[i].listen_host == NULL) ?
 897                     (options.gateway_ports ? "*" : "LOCALHOST") :
 898                     options.local_forwards[i].listen_host,
 899                     options.local_forwards[i].listen_port,
 900                     options.local_forwards[i].connect_host,
 901                     options.local_forwards[i].connect_port);
 902                 success += channel_setup_local_fwd_listener(
 903                     options.local_forwards[i].listen_host,
 904                     options.local_forwards[i].listen_port,
 905                     options.local_forwards[i].connect_host,
 906                     options.local_forwards[i].connect_port,
 907                     options.gateway_ports);
 908         }
 909         if (i > 0 && success != i && options.exit_on_forward_failure)
 910                 fatal("Could not request local forwarding.");
 911         if (i > 0 && success == 0)
 912                 error("Could not request local forwarding.");
 913
 914         /* Initiate remote TCP/IP port forwardings. */
 915         for (i = 0; i < options.num_remote_forwards; i++) {
 916                 debug("Remote connections from %.200s:%d forwarded to "
 917                     "local address %.200s:%d",
 918                     (options.remote_forwards[i].listen_host == NULL) ?
 919                     "LOCALHOST" : options.remote_forwards[i].listen_host,
 920                     options.remote_forwards[i].listen_port,
 921                     options.remote_forwards[i].connect_host,
 922                     options.remote_forwards[i].connect_port);
 923                 if (channel_request_remote_forwarding(
 924                     options.remote_forwards[i].listen_host,
 925                     options.remote_forwards[i].listen_port,
 926                     options.remote_forwards[i].connect_host,
 927                     options.remote_forwards[i].connect_port) < 0) {
 928                         if (options.exit_on_forward_failure)
 929                                 fatal("Could not request remote forwarding.");
 930                         else
 931                                 logit("Warning: Could not request remote "
 932                                     "forwarding.");
 933                 }
 934                 client_register_global_confirm(ssh_confirm_remote_forward,
 935                     &options.remote_forwards[i]);
 936         }
 937
 938         /* Initiate tunnel forwarding. */
 939         if (options.tun_open != SSH_TUNMODE_NO) {
 940                 if (client_request_tun_fwd(options.tun_open,
 941                     options.tun_local, options.tun_remote) == -1) {
 942                         if (options.exit_on_forward_failure)
 943                                 fatal("Could not request tunnel forwarding.");
 944                         else
 945                                 error("Could not request tunnel forwarding.");
 946                 }
 947         }
 948 }
 949
 950 static void
 951 check_agent_present(void)
 952 {
 953         if (options.forward_agent) {
 954                 /* Clear agent forwarding if we don't have an agent. */
 955                 if (!ssh_agent_present())
 956                         options.forward_agent = 0;
 957         }
 958 }
 959
 960 static int
 961 ssh_session(void)
 962 {
 963         int type;
 964         int interactive = 0;
 965         int have_tty = 0;
 966         struct winsize ws;
 967         char *cp;
 968         const char *display;
 969
 970         /* Enable compression if requested. */
 971         if (options.compression) {
 972                 debug("Requesting compression at level %d.",
 973                     options.compression_level);
 974
 975                 if (options.compression_level < 1 ||
 976                     options.compression_level > 9)
 977                         fatal("Compression level must be from 1 (fast) to "
 978                             "9 (slow, best).");
 979
 980                 /* Send the request. */
 981                 packet_start(SSH_CMSG_REQUEST_COMPRESSION);
 982                 packet_put_int(options.compression_level);
 983                 packet_send();
 984                 packet_write_wait();
 985                 type = packet_read();
 986                 if (type == SSH_SMSG_SUCCESS)
 987                         packet_start_compression(options.compression_level);
 988                 else if (type == SSH_SMSG_FAILURE)
 989                         logit("Warning: Remote host refused compression.");
 990                 else
 991                         packet_disconnect("Protocol error waiting for "
 992                             "compression response.");
 993         }
 994         /* Allocate a pseudo tty if appropriate. */
 995         if (tty_flag) {
 996                 debug("Requesting pty.");
 997
 998                 /* Start the packet. */
 999                 packet_start(SSH_CMSG_REQUEST_PTY);
1000
1001                 /* Store TERM in the packet.  There is no limit on the
1002                    length of the string. */
1003                 cp = getenv("TERM");
1004                 if (!cp)
1005                         cp = "";
1006                 packet_put_cstring(cp);
1007
1008                 /* Store window size in the packet. */
1009                 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1010                         memset(&ws, 0, sizeof(ws));
1011                 packet_put_int((u_int)ws.ws_row);
1012                 packet_put_int((u_int)ws.ws_col);
1013                 packet_put_int((u_int)ws.ws_xpixel);
1014                 packet_put_int((u_int)ws.ws_ypixel);
1015
1016                 /* Store tty modes in the packet. */
1017                 tty_make_modes(fileno(stdin), NULL);
1018
1019                 /* Send the packet, and wait for it to leave. */
1020                 packet_send();
1021                 packet_write_wait();
1022
1023                 /* Read response from the server. */
1024                 type = packet_read();
1025                 if (type == SSH_SMSG_SUCCESS) {
1026                         interactive = 1;
1027                         have_tty = 1;
1028                 } else if (type == SSH_SMSG_FAILURE)
1029                         logit("Warning: Remote host failed or refused to "
1030                             "allocate a pseudo tty.");
1031                 else
1032                         packet_disconnect("Protocol error waiting for pty "
1033                             "request response.");
1034         }
1035         /* Request X11 forwarding if enabled and DISPLAY is set. */
1036         display = getenv("DISPLAY");
1037         if (options.forward_x11 && display != NULL) {
1038                 char *proto, *data;
1039                 /* Get reasonable local authentication information. */
1040                 client_x11_get_proto(display, options.xauth_location,
1041                     options.forward_x11_trusted, &proto, &data);
1042                 /* Request forwarding with authentication spoofing. */
1043                 debug("Requesting X11 forwarding with authentication "
1044                     "spoofing.");
1045                 x11_request_forwarding_with_spoofing(0, display, proto, data);
1046
1047                 /* Read response from the server. */
1048                 type = packet_read();
1049                 if (type == SSH_SMSG_SUCCESS) {
1050                         interactive = 1;
1051                 } else if (type == SSH_SMSG_FAILURE) {
1052                         logit("Warning: Remote host denied X11 forwarding.");
1053                 } else {
1054                         packet_disconnect("Protocol error waiting for X11 "
1055                             "forwarding");
1056                 }
1057         }
1058         /* Tell the packet module whether this is an interactive session. */
1059         packet_set_interactive(interactive);
1060
1061         /* Request authentication agent forwarding if appropriate. */
1062         check_agent_present();
1063
1064         if (options.forward_agent) {
1065                 debug("Requesting authentication agent forwarding.");
1066                 auth_request_forwarding();
1067
1068                 /* Read response from the server. */
1069                 type = packet_read();
1070                 packet_check_eom();
1071                 if (type != SSH_SMSG_SUCCESS)
1072                         logit("Warning: Remote host denied authentication agent forwarding.");
1073         }
1074
1075         /* Initiate port forwardings. */
1076         ssh_init_forwarding();
1077
1078         /* Execute a local command */
1079         if (options.local_command != NULL &&
1080             options.permit_local_command)
1081                 ssh_local_cmd(options.local_command);
1082
1083         /*
1084          * If requested and we are not interested in replies to remote
1085          * forwarding requests, then let ssh continue in the background.
1086          */
1087         if (fork_after_authentication_flag &&
1088             (!options.exit_on_forward_failure ||
1089             options.num_remote_forwards == 0)) {
1090                 fork_after_authentication_flag = 0;
1091                 if (daemon(1, 1) < 0)
1092                         fatal("daemon() failed: %.200s", strerror(errno));
1093         }
1094
1095         /*
1096          * If a command was specified on the command line, execute the
1097          * command now. Otherwise request the server to start a shell.
1098          */
1099         if (buffer_len(&command) > 0) {
1100                 int len = buffer_len(&command);
1101                 if (len > 900)
1102                         len = 900;
1103                 debug("Sending command: %.*s", len,
1104                     (u_char *)buffer_ptr(&command));
1105                 packet_start(SSH_CMSG_EXEC_CMD);
1106                 packet_put_string(buffer_ptr(&command), buffer_len(&command));
1107                 packet_send();
1108                 packet_write_wait();
1109         } else {
1110                 debug("Requesting shell.");
1111                 packet_start(SSH_CMSG_EXEC_SHELL);
1112                 packet_send();
1113                 packet_write_wait();
1114         }
1115
1116         /* Enter the interactive session. */
1117         return client_loop(have_tty, tty_flag ?
1118             options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1119 }
1120
1121 /* request pty/x11/agent/tcpfwd/shell for channel */
1122 static void
1123 ssh_session2_setup(int id, void *arg)
1124 {
1125         extern char **environ;
1126         const char *display;
1127         int interactive = tty_flag;
1128
1129         display = getenv("DISPLAY");
1130         if (options.forward_x11 && display != NULL) {
1131                 char *proto, *data;
1132                 /* Get reasonable local authentication information. */
1133                 client_x11_get_proto(display, options.xauth_location,
1134                     options.forward_x11_trusted, &proto, &data);
1135                 /* Request forwarding with authentication spoofing. */
1136                 debug("Requesting X11 forwarding with authentication "
1137                     "spoofing.");
1138                 x11_request_forwarding_with_spoofing(id, display, proto, data);
1139                 interactive = 1;
1140                 /* XXX wait for reply */
1141         }
1142
1143         check_agent_present();
1144         if (options.forward_agent) {
1145                 debug("Requesting authentication agent forwarding.");
1146                 channel_request_start(id, "auth-agent-req@openssh.com", 0);
1147                 packet_send();
1148         }
1149
1150         client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1151             NULL, fileno(stdin), &command, environ);
1152
1153         packet_set_interactive(interactive);
1154 }
1155
1156 /* open new channel for a session */
1157 static int
1158 ssh_session2_open(void)
1159 {
1160         Channel *c;
1161         int window, packetmax, in, out, err;
1162
1163         if (stdin_null_flag) {
1164                 in = open(_PATH_DEVNULL, O_RDONLY);
1165         } else {
1166                 in = dup(STDIN_FILENO);
1167         }
1168         out = dup(STDOUT_FILENO);
1169         err = dup(STDERR_FILENO);
1170
1171         if (in < 0 || out < 0 || err < 0)
1172                 fatal("dup() in/out/err failed");
1173
1174         /* enable nonblocking unless tty */
1175         if (!isatty(in))
1176                 set_nonblock(in);
1177         if (!isatty(out))
1178                 set_nonblock(out);
1179         if (!isatty(err))
1180                 set_nonblock(err);
1181
1182         window = CHAN_SES_WINDOW_DEFAULT;
1183         packetmax = CHAN_SES_PACKET_DEFAULT;
1184         if (tty_flag) {
1185                 window >>= 1;
1186                 packetmax >>= 1;
1187         }
1188         c = channel_new(
1189             "session", SSH_CHANNEL_OPENING, in, out, err,
1190             window, packetmax, CHAN_EXTENDED_WRITE,
1191             "client-session", /*nonblock*/0);
1192
1193         debug3("ssh_session2_open: channel_new: %d", c->self);
1194
1195         channel_send_open(c->self);
1196         if (!no_shell_flag)
1197                 channel_register_open_confirm(c->self,
1198                     ssh_session2_setup, NULL);
1199
1200         return c->self;
1201 }
1202
1203 static int
1204 ssh_session2(void)
1205 {
1206         int id = -1;
1207
1208         /* XXX should be pre-session */
1209         ssh_init_forwarding();
1210
1211         if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1212                 id = ssh_session2_open();
1213
1214         /* If we don't expect to open a new session, then disallow it */
1215         if (options.control_master == SSHCTL_MASTER_NO &&
1216             (datafellows & SSH_NEW_OPENSSH)) {
1217                 debug("Requesting no-more-sessions@openssh.com");
1218                 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1219                 packet_put_cstring("no-more-sessions@openssh.com");
1220                 packet_put_char(0);
1221                 packet_send();
1222         }
1223
1224         /* Execute a local command */
1225         if (options.local_command != NULL &&
1226             options.permit_local_command)
1227                 ssh_local_cmd(options.local_command);
1228
1229         /* Start listening for multiplex clients */
1230         muxserver_listen();
1231
1232         /* If requested, let ssh continue in the background. */
1233         if (fork_after_authentication_flag) {
1234                 fork_after_authentication_flag = 0;
1235                 if (daemon(1, 1) < 0)
1236                         fatal("daemon() failed: %.200s", strerror(errno));
1237         }
1238
1239         return client_loop(tty_flag, tty_flag ?
1240             options.escape_char : SSH_ESCAPECHAR_NONE, id);
1241 }
1242
1243 static void
1244 load_public_identity_files(void)
1245 {
1246         char *filename, *cp, thishost[NI_MAXHOST];
1247         char *pwdir = NULL, *pwname = NULL;
1248         int i = 0;
1249         Key *public;
1250         struct passwd *pw;
1251 #ifdef SMARTCARD
1252         Key **keys;
1253
1254         if (options.smartcard_device != NULL &&
1255             options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1256             (keys = sc_get_keys(options.smartcard_device, NULL)) != NULL) {
1257                 int count = 0;
1258                 for (i = 0; keys[i] != NULL; i++) {
1259                         count++;
1260                         memmove(&options.identity_files[1],
1261                             &options.identity_files[0],
1262                             sizeof(char *) * (SSH_MAX_IDENTITY_FILES - 1));
1263                         memmove(&options.identity_keys[1],
1264                             &options.identity_keys[0],
1265                             sizeof(Key *) * (SSH_MAX_IDENTITY_FILES - 1));
1266                         options.num_identity_files++;
1267                         options.identity_keys[0] = keys[i];
1268                         options.identity_files[0] = sc_get_key_label(keys[i]);
1269                 }
1270                 if (options.num_identity_files > SSH_MAX_IDENTITY_FILES)
1271                         options.num_identity_files = SSH_MAX_IDENTITY_FILES;
1272                 i = count;
1273                 xfree(keys);
1274         }
1275 #endif /* SMARTCARD */
1276         if ((pw = getpwuid(original_real_uid)) == NULL)
1277                 fatal("load_public_identity_files: getpwuid failed");
1278         pwname = xstrdup(pw->pw_name);
1279         pwdir = xstrdup(pw->pw_dir);
1280         if (gethostname(thishost, sizeof(thishost)) == -1)
1281                 fatal("load_public_identity_files: gethostname: %s",
1282                     strerror(errno));
1283         for (; i < options.num_identity_files; i++) {
1284                 cp = tilde_expand_filename(options.identity_files[i],
1285                     original_real_uid);
1286                 filename = percent_expand(cp, "d", pwdir,
1287                     "u", pwname, "l", thishost, "h", host,
1288                     "r", options.user, (char *)NULL);
1289                 xfree(cp);
1290                 public = key_load_public(filename, NULL);
1291                 debug("identity file %s type %d", filename,
1292                     public ? public->type : -1);
1293                 xfree(options.identity_files[i]);
1294                 options.identity_files[i] = filename;
1295                 options.identity_keys[i] = public;
1296         }
1297         bzero(pwname, strlen(pwname));
1298         xfree(pwname);
1299         bzero(pwdir, strlen(pwdir));
1300         xfree(pwdir);
1301 }