Annotation of src/usr.bin/ssh/ssh.c, Revision 1.345
1.345 ! djm 1: /* $OpenBSD: ssh.c,v 1.344 2010/07/19 09:15:12 djm Exp $ */
1.1 deraadt 2: /*
1.32 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * Ssh client program. This program can be used to log into a remote machine.
7: * The software supports strong authentication, encryption, and forwarding
8: * of X11, TCP/IP, and authentication connections.
9: *
1.64 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
16: * Copyright (c) 1999 Niels Provos. All rights reserved.
1.202 markus 17: * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
1.64 deraadt 18: *
19: * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20: * in Canada (German citizen).
21: *
22: * Redistribution and use in source and binary forms, with or without
23: * modification, are permitted provided that the following conditions
24: * are met:
25: * 1. Redistributions of source code must retain the above copyright
26: * notice, this list of conditions and the following disclaimer.
27: * 2. Redistributions in binary form must reproduce the above copyright
28: * notice, this list of conditions and the following disclaimer in the
29: * documentation and/or other materials provided with the distribution.
30: *
31: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 deraadt 41: */
1.1 deraadt 42:
1.293 deraadt 43: #include <sys/types.h>
1.312 djm 44: #include <sys/ioctl.h>
1.326 dtucker 45: #include <sys/param.h>
1.312 djm 46: #include <sys/queue.h>
1.259 stevesk 47: #include <sys/resource.h>
1.280 stevesk 48: #include <sys/socket.h>
1.264 stevesk 49: #include <sys/stat.h>
1.312 djm 50: #include <sys/types.h>
51: #include <sys/time.h>
1.258 stevesk 52:
1.265 stevesk 53: #include <ctype.h>
1.285 stevesk 54: #include <errno.h>
1.281 stevesk 55: #include <fcntl.h>
1.286 stevesk 56: #include <netdb.h>
1.258 stevesk 57: #include <paths.h>
1.279 stevesk 58: #include <pwd.h>
1.263 stevesk 59: #include <signal.h>
1.287 stevesk 60: #include <stddef.h>
1.291 stevesk 61: #include <stdio.h>
1.290 stevesk 62: #include <stdlib.h>
1.289 stevesk 63: #include <string.h>
1.288 stevesk 64: #include <unistd.h>
1.49 markus 65:
66: #include <openssl/evp.h>
1.72 markus 67: #include <openssl/err.h>
1.1 deraadt 68:
1.293 deraadt 69: #include "xmalloc.h"
1.84 markus 70: #include "ssh.h"
71: #include "ssh1.h"
72: #include "ssh2.h"
1.341 djm 73: #include "canohost.h"
1.84 markus 74: #include "compat.h"
75: #include "cipher.h"
1.1 deraadt 76: #include "packet.h"
77: #include "buffer.h"
1.123 markus 78: #include "channels.h"
1.49 markus 79: #include "key.h"
1.58 markus 80: #include "authfd.h"
1.49 markus 81: #include "authfile.h"
1.83 markus 82: #include "pathnames.h"
1.214 djm 83: #include "dispatch.h"
1.81 markus 84: #include "clientloop.h"
1.84 markus 85: #include "log.h"
86: #include "readconf.h"
87: #include "sshconnect.h"
88: #include "misc.h"
1.95 markus 89: #include "kex.h"
90: #include "mac.h"
1.213 deraadt 91: #include "sshpty.h"
1.212 djm 92: #include "match.h"
1.214 djm 93: #include "msg.h"
1.225 dtucker 94: #include "uidswap.h"
1.327 andreas 95: #include "roaming.h"
1.278 stevesk 96: #include "version.h"
1.49 markus 97:
1.333 markus 98: #ifdef ENABLE_PKCS11
99: #include "ssh-pkcs11.h"
1.137 jakob 100: #endif
1.127 markus 101:
1.49 markus 102: extern char *__progname;
1.1 deraadt 103:
1.316 djm 104: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 105: int debug_flag = 0;
106:
1.46 markus 107: /* Flag indicating whether a tty should be allocated */
1.1 deraadt 108: int tty_flag = 0;
1.79 markus 109: int no_tty_flag = 0;
110: int force_tty_flag = 0;
1.1 deraadt 111:
1.45 markus 112: /* don't exec a shell */
113: int no_shell_flag = 0;
114:
1.33 markus 115: /*
116: * Flag indicating that nothing should be read from stdin. This can be set
117: * on the command line.
118: */
1.1 deraadt 119: int stdin_null_flag = 0;
120:
1.33 markus 121: /*
1.344 djm 122: * Flag indicating that the current process should be backgrounded and
123: * a new slave launched in the foreground for ControlPersist.
124: */
125: int need_controlpersist_detach = 0;
126:
127: /* Copies of flags for ControlPersist foreground slave */
128: int ostdin_null_flag, ono_shell_flag, ono_tty_flag, otty_flag;
129:
130: /*
1.33 markus 131: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 132: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 133: * background.
134: */
1.1 deraadt 135: int fork_after_authentication_flag = 0;
136:
1.331 dtucker 137: /* forward stdio to remote host and port */
138: char *stdio_forward_host = NULL;
139: int stdio_forward_port = 0;
140:
1.33 markus 141: /*
142: * General data structure for command line options and options configurable
143: * in configuration files. See readconf.h.
144: */
1.1 deraadt 145: Options options;
146:
1.139 markus 147: /* optional user configfile */
148: char *config = NULL;
149:
1.33 markus 150: /*
151: * Name of the host we are connecting to. This is the name given on the
152: * command line, or the HostName specified for the user-supplied name in a
153: * configuration file.
154: */
1.1 deraadt 155: char *host;
156:
1.22 provos 157: /* socket address the host resolves to */
1.37 markus 158: struct sockaddr_storage hostaddr;
1.1 deraadt 159:
1.112 markus 160: /* Private host keys. */
1.173 markus 161: Sensitive sensitive_data;
1.1 deraadt 162:
1.10 dugsong 163: /* Original real UID. */
164: uid_t original_real_uid;
1.177 markus 165: uid_t original_effective_uid;
1.1 deraadt 166:
1.45 markus 167: /* command to be executed */
168: Buffer command;
169:
1.85 djm 170: /* Should we execute a command or invoke a subsystem? */
171: int subsystem_flag = 0;
172:
1.170 markus 173: /* # of replies received for global requests */
1.315 djm 174: static int remote_forward_confirms_received = 0;
1.170 markus 175:
1.186 djm 176: /* pid of proxycommand child process */
177: pid_t proxy_command_pid = 0;
1.313 djm 178:
179: /* mux.c */
180: extern int muxserver_sock;
181: extern u_int muxclient_command;
182:
1.186 djm 183:
1.1 deraadt 184: /* Prints a help message to the user. This function never returns. */
185:
1.126 itojun 186: static void
1.93 itojun 187: usage(void)
1.1 deraadt 188: {
1.208 markus 189: fprintf(stderr,
1.321 jmc 190: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.251 jmc 191: " [-D [bind_address:]port] [-e escape_char] [-F configfile]\n"
1.334 jmc 192: " [-I pkcs11] [-i identity_file]\n"
193: " [-L [bind_address:]port:host:hostport]\n"
1.232 djm 194: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 195: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.331 dtucker 196: " [-W host:port] [-w local_tun[:remote_tun]]\n"
197: " [user@]hostname [command]\n"
1.208 markus 198: );
1.257 dtucker 199: exit(255);
1.1 deraadt 200: }
201:
1.126 itojun 202: static int ssh_session(void);
203: static int ssh_session2(void);
204: static void load_public_identity_files(void);
1.312 djm 205:
206: /* from muxclient.c */
207: void muxclient(const char *);
208: void muxserver_listen(void);
1.45 markus 209:
1.32 deraadt 210: /*
211: * Main program for the ssh client.
212: */
1.2 provos 213: int
214: main(int ac, char **av)
1.1 deraadt 215: {
1.326 dtucker 216: int i, r, opt, exit_status, use_syslog;
217: char *p, *cp, *line, *argv0, buf[MAXPATHLEN];
1.31 markus 218: struct stat st;
1.98 markus 219: struct passwd *pw;
1.303 djm 220: int dummy, timeout_ms;
1.144 stevesk 221: extern int optind, optreset;
222: extern char *optarg;
1.244 djm 223: struct servent *sp;
1.232 djm 224: Forward fwd;
1.250 djm 225:
226: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
227: sanitise_stdfd();
1.31 markus 228:
1.33 markus 229: /*
230: * Save the original real uid. It will be needed later (uid-swapping
231: * may clobber the real uid).
232: */
1.31 markus 233: original_real_uid = getuid();
234: original_effective_uid = geteuid();
235:
1.184 stevesk 236: /*
237: * Use uid-swapping to give up root privileges for the duration of
238: * option processing. We will re-instantiate the rights when we are
239: * ready to create the privileged port, and will permanently drop
240: * them when the port has been created (actually, when the connection
241: * has been made, as we may need to create the port several times).
242: */
243: PRIV_END;
244:
1.31 markus 245: /* If we are installed setuid root be careful to not drop core. */
246: if (original_real_uid != original_effective_uid) {
247: struct rlimit rlim;
248: rlim.rlim_cur = rlim.rlim_max = 0;
249: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
250: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 251: }
1.107 markus 252: /* Get user data. */
253: pw = getpwuid(original_real_uid);
254: if (!pw) {
1.191 itojun 255: logit("You don't exist, go away!");
1.257 dtucker 256: exit(255);
1.107 markus 257: }
258: /* Take a copy of the returned structure. */
259: pw = pwcopy(pw);
1.31 markus 260:
1.33 markus 261: /*
262: * Set our umask to something reasonable, as some files are created
263: * with the default umask. This will make them world-readable but
264: * writable only by the owner, which is ok for all files for which we
265: * don't set the modes explicitly.
266: */
1.31 markus 267: umask(022);
268:
1.316 djm 269: /*
270: * Initialize option structure to indicate that no values have been
271: * set.
272: */
1.31 markus 273: initialize_options(&options);
274:
275: /* Parse command-line arguments. */
276: host = NULL;
1.320 djm 277: use_syslog = 0;
1.325 markus 278: argv0 = av[0];
1.31 markus 279:
1.266 djm 280: again:
1.316 djm 281: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.331 dtucker 282: "ACD:F:I:KL:MNO:PR:S:TVw:W:XYy")) != -1) {
1.31 markus 283: switch (opt) {
1.91 jakob 284: case '1':
285: options.protocol = SSH_PROTO_1;
286: break;
1.47 markus 287: case '2':
288: options.protocol = SSH_PROTO_2;
289: break;
1.37 markus 290: case '4':
1.196 djm 291: options.address_family = AF_INET;
1.37 markus 292: break;
293: case '6':
1.196 djm 294: options.address_family = AF_INET6;
1.37 markus 295: break;
1.31 markus 296: case 'n':
297: stdin_null_flag = 1;
298: break;
299: case 'f':
300: fork_after_authentication_flag = 1;
301: stdin_null_flag = 1;
302: break;
303: case 'x':
304: options.forward_x11 = 0;
305: break;
306: case 'X':
307: options.forward_x11 = 1;
308: break;
1.320 djm 309: case 'y':
310: use_syslog = 1;
311: break;
1.202 markus 312: case 'Y':
313: options.forward_x11 = 1;
314: options.forward_x11_trusted = 1;
315: break;
1.31 markus 316: case 'g':
317: options.gateway_ports = 1;
318: break;
1.229 djm 319: case 'O':
1.332 djm 320: if (stdio_forward_host != NULL)
321: fatal("Cannot specify multiplexing "
322: "command with -W");
323: else if (muxclient_command != 0)
324: fatal("Multiplexing command already specified");
1.229 djm 325: if (strcmp(optarg, "check") == 0)
1.312 djm 326: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 327: else if (strcmp(optarg, "forward") == 0)
328: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 329: else if (strcmp(optarg, "exit") == 0)
1.312 djm 330: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.229 djm 331: else
332: fatal("Invalid multiplex command.");
333: break;
1.183 stevesk 334: case 'P': /* deprecated */
1.31 markus 335: options.use_privileged_port = 0;
336: break;
337: case 'a':
338: options.forward_agent = 0;
1.53 markus 339: break;
340: case 'A':
341: options.forward_agent = 1;
1.31 markus 342: break;
343: case 'k':
1.204 dtucker 344: options.gss_deleg_creds = 0;
1.297 djm 345: break;
346: case 'K':
347: options.gss_authentication = 1;
348: options.gss_deleg_creds = 1;
1.31 markus 349: break;
350: case 'i':
351: if (stat(optarg, &st) < 0) {
1.128 fgsch 352: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 353: "not accessible: %s.\n", optarg,
354: strerror(errno));
1.31 markus 355: break;
356: }
1.128 fgsch 357: if (options.num_identity_files >=
358: SSH_MAX_IDENTITY_FILES)
359: fatal("Too many identity files specified "
360: "(max %d)", SSH_MAX_IDENTITY_FILES);
361: options.identity_files[options.num_identity_files++] =
362: xstrdup(optarg);
1.31 markus 363: break;
1.127 markus 364: case 'I':
1.333 markus 365: #ifdef ENABLE_PKCS11
366: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 367: #else
1.333 markus 368: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 369: #endif
1.127 markus 370: break;
1.31 markus 371: case 't':
1.79 markus 372: if (tty_flag)
373: force_tty_flag = 1;
1.31 markus 374: tty_flag = 1;
375: break;
376: case 'v':
1.197 markus 377: if (debug_flag == 0) {
1.66 markus 378: debug_flag = 1;
379: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 380: } else {
381: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
382: options.log_level++;
1.66 markus 383: break;
1.197 markus 384: }
1.227 deraadt 385: /* FALLTHROUGH */
1.31 markus 386: case 'V':
1.209 markus 387: fprintf(stderr, "%s, %s\n",
388: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 389: if (opt == 'V')
390: exit(0);
391: break;
1.255 reyk 392: case 'w':
1.256 reyk 393: if (options.tun_open == -1)
394: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 395: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 396: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 397: fprintf(stderr,
398: "Bad tun device '%s'\n", optarg);
1.257 dtucker 399: exit(255);
1.255 reyk 400: }
401: break;
1.331 dtucker 402: case 'W':
1.332 djm 403: if (stdio_forward_host != NULL)
404: fatal("stdio forward already specified");
405: if (muxclient_command != 0)
406: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 407: if (parse_forward(&fwd, optarg, 1, 0)) {
408: stdio_forward_host = fwd.listen_host;
409: stdio_forward_port = fwd.listen_port;
410: xfree(fwd.connect_host);
411: } else {
412: fprintf(stderr,
413: "Bad stdio forwarding specification '%s'\n",
414: optarg);
415: exit(255);
416: }
417: no_tty_flag = 1;
418: no_shell_flag = 1;
419: options.clear_forwardings = 1;
420: options.exit_on_forward_failure = 1;
421: break;
1.31 markus 422: case 'q':
423: options.log_level = SYSLOG_LEVEL_QUIET;
424: break;
425: case 'e':
426: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 427: (u_char) optarg[1] >= 64 &&
428: (u_char) optarg[1] < 128)
1.78 markus 429: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 430: else if (strlen(optarg) == 1)
1.78 markus 431: options.escape_char = (u_char) optarg[0];
1.31 markus 432: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 433: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 434: else {
1.128 fgsch 435: fprintf(stderr, "Bad escape character '%s'.\n",
436: optarg);
1.257 dtucker 437: exit(255);
1.31 markus 438: }
439: break;
440: case 'c':
1.49 markus 441: if (ciphers_valid(optarg)) {
442: /* SSH2 only */
443: options.ciphers = xstrdup(optarg);
1.224 markus 444: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 445: } else {
446: /* SSH1 only */
1.74 markus 447: options.cipher = cipher_number(optarg);
448: if (options.cipher == -1) {
1.128 fgsch 449: fprintf(stderr,
450: "Unknown cipher type '%s'\n",
451: optarg);
1.257 dtucker 452: exit(255);
1.49 markus 453: }
1.128 fgsch 454: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 455: options.ciphers = "3des-cbc";
1.128 fgsch 456: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 457: options.ciphers = "blowfish-cbc";
1.128 fgsch 458: else
1.74 markus 459: options.ciphers = (char *)-1;
1.95 markus 460: }
461: break;
462: case 'm':
463: if (mac_valid(optarg))
464: options.macs = xstrdup(optarg);
465: else {
1.128 fgsch 466: fprintf(stderr, "Unknown mac type '%s'\n",
467: optarg);
1.257 dtucker 468: exit(255);
1.31 markus 469: }
470: break;
1.214 djm 471: case 'M':
1.242 djm 472: if (options.control_master == SSHCTL_MASTER_YES)
473: options.control_master = SSHCTL_MASTER_ASK;
474: else
475: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 476: break;
1.31 markus 477: case 'p':
1.113 stevesk 478: options.port = a2port(optarg);
1.323 djm 479: if (options.port <= 0) {
1.109 markus 480: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 481: exit(255);
1.109 markus 482: }
1.31 markus 483: break;
484: case 'l':
485: options.user = optarg;
486: break;
1.141 stevesk 487:
488: case 'L':
1.324 djm 489: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 490: add_local_forward(&options, &fwd);
491: else {
1.128 fgsch 492: fprintf(stderr,
1.232 djm 493: "Bad local forwarding specification '%s'\n",
1.128 fgsch 494: optarg);
1.257 dtucker 495: exit(255);
1.31 markus 496: }
1.232 djm 497: break;
498:
499: case 'R':
1.324 djm 500: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 501: add_remote_forward(&options, &fwd);
502: } else {
1.128 fgsch 503: fprintf(stderr,
1.232 djm 504: "Bad remote forwarding specification "
505: "'%s'\n", optarg);
1.257 dtucker 506: exit(255);
1.31 markus 507: }
508: break;
1.108 markus 509:
510: case 'D':
1.324 djm 511: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 512: add_local_forward(&options, &fwd);
1.232 djm 513: } else {
1.322 stevesk 514: fprintf(stderr,
515: "Bad dynamic forwarding specification "
516: "'%s'\n", optarg);
1.257 dtucker 517: exit(255);
1.109 markus 518: }
1.108 markus 519: break;
520:
1.31 markus 521: case 'C':
522: options.compression = 1;
523: break;
1.45 markus 524: case 'N':
525: no_shell_flag = 1;
526: no_tty_flag = 1;
527: break;
528: case 'T':
529: no_tty_flag = 1;
530: break;
1.31 markus 531: case 'o':
532: dummy = 1;
1.205 markus 533: line = xstrdup(optarg);
1.128 fgsch 534: if (process_config_line(&options, host ? host : "",
1.205 markus 535: line, "command-line", 0, &dummy) != 0)
1.257 dtucker 536: exit(255);
1.205 markus 537: xfree(line);
1.31 markus 538: break;
1.85 djm 539: case 's':
540: subsystem_flag = 1;
1.117 markus 541: break;
1.214 djm 542: case 'S':
543: if (options.control_path != NULL)
544: free(options.control_path);
545: options.control_path = xstrdup(optarg);
546: break;
1.117 markus 547: case 'b':
548: options.bind_address = optarg;
1.85 djm 549: break;
1.139 markus 550: case 'F':
551: config = optarg;
552: break;
1.31 markus 553: default:
554: usage();
1.1 deraadt 555: }
1.31 markus 556: }
557:
1.128 fgsch 558: ac -= optind;
559: av += optind;
560:
1.329 guenther 561: if (ac > 0 && !host) {
1.188 markus 562: if (strrchr(*av, '@')) {
1.128 fgsch 563: p = xstrdup(*av);
1.188 markus 564: cp = strrchr(p, '@');
1.128 fgsch 565: if (cp == NULL || cp == p)
566: usage();
567: options.user = p;
568: *cp = '\0';
569: host = ++cp;
570: } else
571: host = *av;
1.189 millert 572: if (ac > 1) {
573: optind = optreset = 1;
1.128 fgsch 574: goto again;
575: }
1.189 millert 576: ac--, av++;
1.128 fgsch 577: }
578:
1.31 markus 579: /* Check that we got a host name. */
580: if (!host)
581: usage();
582:
1.54 markus 583: SSLeay_add_all_algorithms();
1.72 markus 584: ERR_load_crypto_strings();
1.31 markus 585:
586: /* Initialize the command to execute on remote host. */
587: buffer_init(&command);
1.1 deraadt 588:
1.33 markus 589: /*
590: * Save the command to execute on the remote host in a buffer. There
591: * is no limit on the length of the command, except by the maximum
592: * packet size. Also sets the tty flag if there is no command.
593: */
1.128 fgsch 594: if (!ac) {
1.31 markus 595: /* No command specified - execute shell on a tty. */
596: tty_flag = 1;
1.85 djm 597: if (subsystem_flag) {
1.128 fgsch 598: fprintf(stderr,
599: "You must specify a subsystem to invoke.\n");
1.85 djm 600: usage();
601: }
1.31 markus 602: } else {
1.128 fgsch 603: /* A command has been specified. Store it into the buffer. */
604: for (i = 0; i < ac; i++) {
605: if (i)
1.31 markus 606: buffer_append(&command, " ", 1);
607: buffer_append(&command, av[i], strlen(av[i]));
608: }
609: }
610:
611: /* Cannot fork to background if no command. */
1.316 djm 612: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
613: !no_shell_flag)
614: fatal("Cannot fork into background without a command "
615: "to execute.");
1.31 markus 616:
617: /* Allocate a tty by default if no command specified. */
618: if (buffer_len(&command) == 0)
619: tty_flag = 1;
620:
1.180 deraadt 621: /* Force no tty */
1.336 djm 622: if (no_tty_flag || muxclient_command != 0)
1.75 markus 623: tty_flag = 0;
1.31 markus 624: /* Do not allocate a tty if stdin is not a tty. */
1.236 djm 625: if ((!isatty(fileno(stdin)) || stdin_null_flag) && !force_tty_flag) {
1.31 markus 626: if (tty_flag)
1.316 djm 627: logit("Pseudo-terminal will not be allocated because "
628: "stdin is not a terminal.");
1.31 markus 629: tty_flag = 0;
630: }
1.45 markus 631:
1.101 markus 632: /*
633: * Initialize "log" output. Since we are the client all output
634: * actually goes to stderr.
635: */
1.325 markus 636: log_init(argv0,
1.316 djm 637: options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
1.320 djm 638: SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 639:
1.139 markus 640: /*
641: * Read per-user configuration file. Ignore the system wide config
642: * file if the user specifies a config file on the command line.
643: */
644: if (config != NULL) {
1.211 djm 645: if (!read_config_file(config, host, &options, 0))
1.142 stevesk 646: fatal("Can't open user config file %.100s: "
647: "%.100s", config, strerror(errno));
1.295 stevesk 648: } else {
1.326 dtucker 649: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
1.139 markus 650: _PATH_SSH_USER_CONFFILE);
1.326 dtucker 651: if (r > 0 && (size_t)r < sizeof(buf))
652: (void)read_config_file(buf, host, &options, 1);
1.139 markus 653:
1.145 markus 654: /* Read systemwide configuration file after use config. */
1.223 deraadt 655: (void)read_config_file(_PATH_HOST_CONFIG_FILE, host,
1.210 djm 656: &options, 0);
1.139 markus 657: }
1.31 markus 658:
659: /* Fill configuration defaults. */
660: fill_default_options(&options);
661:
1.196 djm 662: channel_set_af(options.address_family);
663:
1.31 markus 664: /* reinit */
1.325 markus 665: log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1.31 markus 666:
667: if (options.user == NULL)
668: options.user = xstrdup(pw->pw_name);
669:
1.317 dtucker 670: /* Get default port if port has not been set. */
671: if (options.port == 0) {
672: sp = getservbyname(SSH_SERVICE_NAME, "tcp");
673: options.port = sp ? ntohs(sp->s_port) : SSH_DEFAULT_PORT;
674: }
675:
1.343 djm 676: if (options.hostname != NULL) {
677: host = percent_expand(options.hostname,
678: "h", host, (char *)NULL);
679: }
680:
1.317 dtucker 681: if (options.local_command != NULL) {
682: char thishost[NI_MAXHOST];
683:
684: if (gethostname(thishost, sizeof(thishost)) == -1)
685: fatal("gethostname: %s", strerror(errno));
686: snprintf(buf, sizeof(buf), "%d", options.port);
687: debug3("expanding LocalCommand: %s", options.local_command);
688: cp = options.local_command;
689: options.local_command = percent_expand(cp, "d", pw->pw_dir,
1.343 djm 690: "h", host, "l", thishost, "n", host, "r", options.user,
691: "p", buf, "u", pw->pw_name, (char *)NULL);
1.317 dtucker 692: debug3("expanded LocalCommand: %s", options.local_command);
693: xfree(cp);
694: }
1.195 markus 695:
696: /* force lowercase for hostkey matching */
697: if (options.host_key_alias != NULL) {
698: for (p = options.host_key_alias; *p; p++)
699: if (isupper(*p))
1.271 deraadt 700: *p = (char)tolower(*p);
1.246 djm 701: }
702:
1.190 markus 703: if (options.proxy_command != NULL &&
1.304 dtucker 704: strcmp(options.proxy_command, "none") == 0) {
705: xfree(options.proxy_command);
1.190 markus 706: options.proxy_command = NULL;
1.304 dtucker 707: }
1.245 djm 708: if (options.control_path != NULL &&
1.304 dtucker 709: strcmp(options.control_path, "none") == 0) {
710: xfree(options.control_path);
1.245 djm 711: options.control_path = NULL;
1.304 dtucker 712: }
1.31 markus 713:
1.214 djm 714: if (options.control_path != NULL) {
1.275 djm 715: char thishost[NI_MAXHOST];
1.261 djm 716:
1.275 djm 717: if (gethostname(thishost, sizeof(thishost)) == -1)
1.261 djm 718: fatal("gethostname: %s", strerror(errno));
1.241 djm 719: snprintf(buf, sizeof(buf), "%d", options.port);
720: cp = tilde_expand_filename(options.control_path,
721: original_real_uid);
1.304 dtucker 722: xfree(options.control_path);
1.241 djm 723: options.control_path = percent_expand(cp, "p", buf, "h", host,
1.275 djm 724: "r", options.user, "l", thishost, (char *)NULL);
1.241 djm 725: xfree(cp);
1.214 djm 726: }
1.312 djm 727: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 728: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 729: if (options.control_path != NULL)
1.312 djm 730: muxclient(options.control_path);
1.214 djm 731:
1.303 djm 732: timeout_ms = options.connection_timeout * 1000;
733:
1.77 markus 734: /* Open a connection to the remote host. */
1.203 djm 735: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 736: options.address_family, options.connection_attempts, &timeout_ms,
737: options.tcp_keep_alive,
1.177 markus 738: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 739: options.proxy_command) != 0)
1.257 dtucker 740: exit(255);
1.31 markus 741:
1.303 djm 742: if (timeout_ms > 0)
743: debug3("timeout: %d ms remain after connect", timeout_ms);
744:
1.33 markus 745: /*
746: * If we successfully made the connection, load the host private key
747: * in case we will need it later for combined rsa-rhosts
748: * authentication. This must be done before releasing extra
749: * privileges, because the file is only readable by root.
1.174 markus 750: * If we cannot access the private keys, load the public keys
751: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 752: */
1.112 markus 753: sensitive_data.nkeys = 0;
754: sensitive_data.keys = NULL;
1.173 markus 755: sensitive_data.external_keysign = 0;
1.178 markus 756: if (options.rhosts_rsa_authentication ||
757: options.hostbased_authentication) {
1.345 ! djm 758: sensitive_data.nkeys = 5;
1.274 deraadt 759: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 760: sizeof(Key));
1.177 markus 761:
762: PRIV_START;
1.112 markus 763: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 764: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.345 ! djm 765: sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
! 766: _PATH_HOST_DSA_KEY_FILE, "", NULL);
! 767: sensitive_data.keys[2] = key_load_private_cert(KEY_RSA,
! 768: _PATH_HOST_RSA_KEY_FILE, "", NULL);
! 769: sensitive_data.keys[3] = key_load_private_type(KEY_DSA,
1.276 dtucker 770: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.345 ! djm 771: sensitive_data.keys[4] = key_load_private_type(KEY_RSA,
1.276 dtucker 772: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 773: PRIV_END;
1.173 markus 774:
1.181 markus 775: if (options.hostbased_authentication == 1 &&
776: sensitive_data.keys[0] == NULL &&
1.345 ! djm 777: sensitive_data.keys[3] == NULL &&
! 778: sensitive_data.keys[4] == NULL) {
! 779: sensitive_data.keys[1] = key_load_cert(
! 780: _PATH_HOST_DSA_KEY_FILE);
! 781: sensitive_data.keys[2] = key_load_cert(
! 782: _PATH_HOST_RSA_KEY_FILE);
! 783: sensitive_data.keys[3] = key_load_public(
1.173 markus 784: _PATH_HOST_DSA_KEY_FILE, NULL);
1.345 ! djm 785: sensitive_data.keys[4] = key_load_public(
1.173 markus 786: _PATH_HOST_RSA_KEY_FILE, NULL);
787: sensitive_data.external_keysign = 1;
788: }
1.31 markus 789: }
1.33 markus 790: /*
791: * Get rid of any extra privileges that we may have. We will no
792: * longer need them. Also, extra privileges could make it very hard
793: * to read identity files and other non-world-readable files from the
794: * user's home directory if it happens to be on a NFS volume where
795: * root is mapped to nobody.
796: */
1.225 dtucker 797: if (original_effective_uid == 0) {
798: PRIV_START;
799: permanently_set_uid(pw);
800: }
1.31 markus 801:
1.33 markus 802: /*
803: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 804: * directory if it doesn't already exist.
1.33 markus 805: */
1.326 dtucker 806: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1.316 djm 807: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1.326 dtucker 808: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
1.57 djm 809: if (mkdir(buf, 0700) < 0)
1.31 markus 810: error("Could not create directory '%.200s'.", buf);
811:
1.104 markus 812: /* load options.identity_files */
813: load_public_identity_files();
814:
815: /* Expand ~ in known host file names. */
816: /* XXX mem-leaks: */
1.72 markus 817: options.system_hostfile =
818: tilde_expand_filename(options.system_hostfile, original_real_uid);
819: options.user_hostfile =
820: tilde_expand_filename(options.user_hostfile, original_real_uid);
821: options.system_hostfile2 =
822: tilde_expand_filename(options.system_hostfile2, original_real_uid);
823: options.user_hostfile2 =
824: tilde_expand_filename(options.user_hostfile2, original_real_uid);
1.149 markus 825:
826: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.31 markus 827:
1.316 djm 828: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 829: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
830: pw, timeout_ms);
1.339 djm 831:
832: if (packet_connection_is_on_socket()) {
833: verbose("Authenticated to %s ([%s]:%d).", host,
834: get_remote_ipaddr(), get_remote_port());
835: } else {
836: verbose("Authenticated to %s (via proxy).", host);
837: }
1.31 markus 838:
1.112 markus 839: /* We no longer need the private host keys. Clear them now. */
840: if (sensitive_data.nkeys != 0) {
841: for (i = 0; i < sensitive_data.nkeys; i++) {
842: if (sensitive_data.keys[i] != NULL) {
843: /* Destroys contents safely */
844: debug3("clear hostkey %d", i);
845: key_free(sensitive_data.keys[i]);
846: sensitive_data.keys[i] = NULL;
847: }
848: }
849: xfree(sensitive_data.keys);
1.134 markus 850: }
851: for (i = 0; i < options.num_identity_files; i++) {
852: if (options.identity_files[i]) {
853: xfree(options.identity_files[i]);
854: options.identity_files[i] = NULL;
855: }
856: if (options.identity_keys[i]) {
857: key_free(options.identity_keys[i]);
858: options.identity_keys[i] = NULL;
859: }
1.112 markus 860: }
1.31 markus 861:
1.45 markus 862: exit_status = compat20 ? ssh_session2() : ssh_session();
863: packet_close();
1.186 djm 864:
1.312 djm 865: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 866: unlink(options.control_path);
867:
1.186 djm 868: /*
1.203 djm 869: * Send SIGHUP to proxy command if used. We don't wait() in
1.186 djm 870: * case it hangs and instead rely on init to reap the child
871: */
872: if (proxy_command_pid > 1)
873: kill(proxy_command_pid, SIGHUP);
874:
1.45 markus 875: return exit_status;
876: }
877:
1.344 djm 878: static void
879: control_persist_detach(void)
880: {
881: pid_t pid;
882:
883: debug("%s: backgrounding master process", __func__);
884:
885: /*
886: * master (current process) into the background, and make the
887: * foreground process a client of the backgrounded master.
888: */
889: switch ((pid = fork())) {
890: case -1:
891: fatal("%s: fork: %s", __func__, strerror(errno));
892: case 0:
893: /* Child: master process continues mainloop */
894: break;
895: default:
896: /* Parent: set up mux slave to connect to backgrounded master */
897: debug2("%s: background process is %ld", __func__, (long)pid);
898: stdin_null_flag = ostdin_null_flag;
899: no_shell_flag = ono_shell_flag;
900: no_tty_flag = ono_tty_flag;
901: tty_flag = otty_flag;
902: close(muxserver_sock);
903: muxserver_sock = -1;
904: muxclient(options.control_path);
905: /* muxclient() doesn't return on success. */
906: fatal("Failed to connect to new control master");
907: }
908: }
909:
910: /* Do fork() after authentication. Used by "ssh -f" */
911: static void
912: fork_postauth(void)
913: {
914: if (need_controlpersist_detach)
915: control_persist_detach();
916: debug("forking to background");
917: fork_after_authentication_flag = 0;
918: if (daemon(1, 1) < 0)
919: fatal("daemon() failed: %.200s", strerror(errno));
920: }
921:
1.315 djm 922: /* Callback for remote forward global requests */
923: static void
924: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
925: {
926: Forward *rfwd = (Forward *)ctxt;
927:
1.324 djm 928: /* XXX verbose() on failure? */
1.315 djm 929: debug("remote forward %s for: listen %d, connect %s:%d",
930: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
931: rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
1.324 djm 932: if (type == SSH2_MSG_REQUEST_SUCCESS && rfwd->listen_port == 0) {
1.338 markus 933: rfwd->allocated_port = packet_get_int();
1.324 djm 934: logit("Allocated port %u for remote forward to %s:%d",
1.338 markus 935: rfwd->allocated_port,
936: rfwd->connect_host, rfwd->connect_port);
1.324 djm 937: }
938:
1.315 djm 939: if (type == SSH2_MSG_REQUEST_FAILURE) {
940: if (options.exit_on_forward_failure)
941: fatal("Error: remote port forwarding failed for "
942: "listen port %d", rfwd->listen_port);
943: else
944: logit("Warning: remote port forwarding failed for "
945: "listen port %d", rfwd->listen_port);
946: }
1.318 djm 947: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 948: debug("All remote forwarding requests processed");
1.344 djm 949: if (fork_after_authentication_flag)
950: fork_postauth();
1.318 djm 951: }
1.315 djm 952: }
953:
1.126 itojun 954: static void
1.331 dtucker 955: client_cleanup_stdio_fwd(int id, void *arg)
956: {
957: debug("stdio forwarding: done");
958: cleanup_exit(0);
959: }
960:
961: static int
962: client_setup_stdio_fwd(const char *host_to_connect, u_short port_to_connect)
963: {
964: Channel *c;
1.332 djm 965: int in, out;
1.331 dtucker 966:
967: debug3("client_setup_stdio_fwd %s:%d", host_to_connect,
968: port_to_connect);
1.332 djm 969:
970: in = dup(STDIN_FILENO);
971: out = dup(STDOUT_FILENO);
972: if (in < 0 || out < 0)
973: fatal("channel_connect_stdio_fwd: dup() in/out failed");
974:
975: if ((c = channel_connect_stdio_fwd(host_to_connect, port_to_connect,
976: in, out)) == NULL)
1.331 dtucker 977: return 0;
978: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
979: return 1;
980: }
981:
982: static void
1.70 markus 983: ssh_init_forwarding(void)
984: {
1.86 markus 985: int success = 0;
1.70 markus 986: int i;
1.331 dtucker 987:
988: if (stdio_forward_host != NULL) {
989: if (!compat20) {
990: fatal("stdio forwarding require Protocol 2");
991: }
992: if (!client_setup_stdio_fwd(stdio_forward_host,
993: stdio_forward_port))
994: fatal("Failed to connect in stdio forward mode.");
995: }
1.86 markus 996:
1.70 markus 997: /* Initiate local TCP/IP port forwardings. */
998: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 999: debug("Local connections to %.200s:%d forwarded to remote "
1000: "address %.200s:%d",
1.234 deraadt 1001: (options.local_forwards[i].listen_host == NULL) ?
1002: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1003: options.local_forwards[i].listen_host,
1004: options.local_forwards[i].listen_port,
1005: options.local_forwards[i].connect_host,
1006: options.local_forwards[i].connect_port);
1.158 markus 1007: success += channel_setup_local_fwd_listener(
1.232 djm 1008: options.local_forwards[i].listen_host,
1009: options.local_forwards[i].listen_port,
1010: options.local_forwards[i].connect_host,
1011: options.local_forwards[i].connect_port,
1.70 markus 1012: options.gateway_ports);
1013: }
1.283 markus 1014: if (i > 0 && success != i && options.exit_on_forward_failure)
1015: fatal("Could not request local forwarding.");
1.86 markus 1016: if (i > 0 && success == 0)
1017: error("Could not request local forwarding.");
1.70 markus 1018:
1019: /* Initiate remote TCP/IP port forwardings. */
1020: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1021: debug("Remote connections from %.200s:%d forwarded to "
1022: "local address %.200s:%d",
1.248 djm 1023: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1024: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1025: options.remote_forwards[i].listen_port,
1026: options.remote_forwards[i].connect_host,
1027: options.remote_forwards[i].connect_port);
1.283 markus 1028: if (channel_request_remote_forwarding(
1.232 djm 1029: options.remote_forwards[i].listen_host,
1030: options.remote_forwards[i].listen_port,
1031: options.remote_forwards[i].connect_host,
1.283 markus 1032: options.remote_forwards[i].connect_port) < 0) {
1033: if (options.exit_on_forward_failure)
1034: fatal("Could not request remote forwarding.");
1035: else
1036: logit("Warning: Could not request remote "
1037: "forwarding.");
1038: }
1.315 djm 1039: client_register_global_confirm(ssh_confirm_remote_forward,
1040: &options.remote_forwards[i]);
1.70 markus 1041: }
1.301 djm 1042:
1043: /* Initiate tunnel forwarding. */
1044: if (options.tun_open != SSH_TUNMODE_NO) {
1045: if (client_request_tun_fwd(options.tun_open,
1046: options.tun_local, options.tun_remote) == -1) {
1047: if (options.exit_on_forward_failure)
1048: fatal("Could not request tunnel forwarding.");
1049: else
1050: error("Could not request tunnel forwarding.");
1051: }
1052: }
1.70 markus 1053: }
1054:
1.126 itojun 1055: static void
1.70 markus 1056: check_agent_present(void)
1057: {
1058: if (options.forward_agent) {
1.254 djm 1059: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 1060: if (!ssh_agent_present())
1.70 markus 1061: options.forward_agent = 0;
1062: }
1063: }
1064:
1.126 itojun 1065: static int
1.45 markus 1066: ssh_session(void)
1067: {
1068: int type;
1069: int interactive = 0;
1070: int have_tty = 0;
1071: struct winsize ws;
1072: char *cp;
1.243 djm 1073: const char *display;
1.45 markus 1074:
1.31 markus 1075: /* Enable compression if requested. */
1076: if (options.compression) {
1.316 djm 1077: debug("Requesting compression at level %d.",
1078: options.compression_level);
1.31 markus 1079:
1.316 djm 1080: if (options.compression_level < 1 ||
1081: options.compression_level > 9)
1082: fatal("Compression level must be from 1 (fast) to "
1083: "9 (slow, best).");
1.31 markus 1084:
1085: /* Send the request. */
1086: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1087: packet_put_int(options.compression_level);
1088: packet_send();
1089: packet_write_wait();
1.156 markus 1090: type = packet_read();
1.31 markus 1091: if (type == SSH_SMSG_SUCCESS)
1092: packet_start_compression(options.compression_level);
1093: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1094: logit("Warning: Remote host refused compression.");
1.31 markus 1095: else
1.316 djm 1096: packet_disconnect("Protocol error waiting for "
1097: "compression response.");
1.31 markus 1098: }
1099: /* Allocate a pseudo tty if appropriate. */
1100: if (tty_flag) {
1101: debug("Requesting pty.");
1102:
1103: /* Start the packet. */
1104: packet_start(SSH_CMSG_REQUEST_PTY);
1105:
1106: /* Store TERM in the packet. There is no limit on the
1107: length of the string. */
1108: cp = getenv("TERM");
1109: if (!cp)
1110: cp = "";
1.124 markus 1111: packet_put_cstring(cp);
1.31 markus 1112:
1113: /* Store window size in the packet. */
1114: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1115: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1116: packet_put_int((u_int)ws.ws_row);
1117: packet_put_int((u_int)ws.ws_col);
1118: packet_put_int((u_int)ws.ws_xpixel);
1119: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1120:
1121: /* Store tty modes in the packet. */
1.115 stevesk 1122: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1123:
1124: /* Send the packet, and wait for it to leave. */
1125: packet_send();
1126: packet_write_wait();
1127:
1128: /* Read response from the server. */
1.156 markus 1129: type = packet_read();
1.43 markus 1130: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1131: interactive = 1;
1.45 markus 1132: have_tty = 1;
1.43 markus 1133: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1134: logit("Warning: Remote host failed or refused to "
1135: "allocate a pseudo tty.");
1.31 markus 1136: else
1.316 djm 1137: packet_disconnect("Protocol error waiting for pty "
1138: "request response.");
1.31 markus 1139: }
1140: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1141: display = getenv("DISPLAY");
1142: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1143: char *proto, *data;
1.50 markus 1144: /* Get reasonable local authentication information. */
1.243 djm 1145: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1146: options.forward_x11_trusted,
1147: options.forward_x11_timeout,
1148: &proto, &data);
1.50 markus 1149: /* Request forwarding with authentication spoofing. */
1.316 djm 1150: debug("Requesting X11 forwarding with authentication "
1151: "spoofing.");
1.243 djm 1152: x11_request_forwarding_with_spoofing(0, display, proto, data);
1.31 markus 1153:
1154: /* Read response from the server. */
1.156 markus 1155: type = packet_read();
1.31 markus 1156: if (type == SSH_SMSG_SUCCESS) {
1157: interactive = 1;
1.50 markus 1158: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1159: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1160: } else {
1.316 djm 1161: packet_disconnect("Protocol error waiting for X11 "
1162: "forwarding");
1.50 markus 1163: }
1.31 markus 1164: }
1165: /* Tell the packet module whether this is an interactive session. */
1.80 markus 1166: packet_set_interactive(interactive);
1.31 markus 1167:
1168: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1169: check_agent_present();
1170:
1.31 markus 1171: if (options.forward_agent) {
1172: debug("Requesting authentication agent forwarding.");
1173: auth_request_forwarding();
1174:
1175: /* Read response from the server. */
1.156 markus 1176: type = packet_read();
1.155 markus 1177: packet_check_eom();
1.31 markus 1178: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1179: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1180: }
1181:
1.70 markus 1182: /* Initiate port forwardings. */
1183: ssh_init_forwarding();
1.305 dtucker 1184:
1185: /* Execute a local command */
1186: if (options.local_command != NULL &&
1187: options.permit_local_command)
1188: ssh_local_cmd(options.local_command);
1.34 markus 1189:
1.318 djm 1190: /*
1191: * If requested and we are not interested in replies to remote
1192: * forwarding requests, then let ssh continue in the background.
1193: */
1.344 djm 1194: if (fork_after_authentication_flag) {
1195: if (options.exit_on_forward_failure &&
1196: options.num_remote_forwards > 0) {
1197: debug("deferring postauth fork until remote forward "
1198: "confirmation received");
1199: } else
1200: fork_postauth();
1.318 djm 1201: }
1.31 markus 1202:
1.33 markus 1203: /*
1204: * If a command was specified on the command line, execute the
1205: * command now. Otherwise request the server to start a shell.
1206: */
1.31 markus 1207: if (buffer_len(&command) > 0) {
1208: int len = buffer_len(&command);
1209: if (len > 900)
1210: len = 900;
1.316 djm 1211: debug("Sending command: %.*s", len,
1212: (u_char *)buffer_ptr(&command));
1.31 markus 1213: packet_start(SSH_CMSG_EXEC_CMD);
1214: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1215: packet_send();
1216: packet_write_wait();
1217: } else {
1218: debug("Requesting shell.");
1219: packet_start(SSH_CMSG_EXEC_SHELL);
1220: packet_send();
1221: packet_write_wait();
1222: }
1223:
1224: /* Enter the interactive session. */
1.119 stevesk 1225: return client_loop(have_tty, tty_flag ?
1226: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1227: }
1228:
1.214 djm 1229: /* request pty/x11/agent/tcpfwd/shell for channel */
1230: static void
1.337 djm 1231: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1232: {
1.215 djm 1233: extern char **environ;
1.243 djm 1234: const char *display;
1235: int interactive = tty_flag;
1.337 djm 1236:
1237: if (!success)
1238: return; /* No need for error message, channels code sens one */
1.215 djm 1239:
1.248 djm 1240: display = getenv("DISPLAY");
1.243 djm 1241: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1242: char *proto, *data;
1.50 markus 1243: /* Get reasonable local authentication information. */
1.243 djm 1244: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1245: options.forward_x11_trusted,
1246: options.forward_x11_timeout, &proto, &data);
1.50 markus 1247: /* Request forwarding with authentication spoofing. */
1.316 djm 1248: debug("Requesting X11 forwarding with authentication "
1249: "spoofing.");
1.243 djm 1250: x11_request_forwarding_with_spoofing(id, display, proto, data);
1.80 markus 1251: interactive = 1;
1.50 markus 1252: /* XXX wait for reply */
1253: }
1254:
1.70 markus 1255: check_agent_present();
1256: if (options.forward_agent) {
1257: debug("Requesting authentication agent forwarding.");
1258: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1259: packet_send();
1.212 djm 1260: }
1261:
1.214 djm 1262: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1263: NULL, fileno(stdin), &command, environ);
1.90 markus 1264:
1.80 markus 1265: packet_set_interactive(interactive);
1.45 markus 1266: }
1267:
1.143 markus 1268: /* open new channel for a session */
1.126 itojun 1269: static int
1.143 markus 1270: ssh_session2_open(void)
1.45 markus 1271: {
1.118 markus 1272: Channel *c;
1273: int window, packetmax, in, out, err;
1.60 markus 1274:
1.62 markus 1275: if (stdin_null_flag) {
1.93 itojun 1276: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1277: } else {
1278: in = dup(STDIN_FILENO);
1279: }
1.60 markus 1280: out = dup(STDOUT_FILENO);
1281: err = dup(STDERR_FILENO);
1.45 markus 1282:
1283: if (in < 0 || out < 0 || err < 0)
1.62 markus 1284: fatal("dup() in/out/err failed");
1.45 markus 1285:
1.69 markus 1286: /* enable nonblocking unless tty */
1287: if (!isatty(in))
1288: set_nonblock(in);
1289: if (!isatty(out))
1290: set_nonblock(out);
1291: if (!isatty(err))
1292: set_nonblock(err);
1293:
1.65 markus 1294: window = CHAN_SES_WINDOW_DEFAULT;
1295: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1296: if (tty_flag) {
1297: window >>= 1;
1298: packetmax >>= 1;
1.45 markus 1299: }
1.118 markus 1300: c = channel_new(
1.45 markus 1301: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1302: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1303: "client-session", /*nonblock*/0);
1.45 markus 1304:
1.143 markus 1305: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1306:
1.122 markus 1307: channel_send_open(c->self);
1.143 markus 1308: if (!no_shell_flag)
1.310 djm 1309: channel_register_open_confirm(c->self,
1310: ssh_session2_setup, NULL);
1.106 markus 1311:
1.118 markus 1312: return c->self;
1.106 markus 1313: }
1314:
1.126 itojun 1315: static int
1.106 markus 1316: ssh_session2(void)
1317: {
1.143 markus 1318: int id = -1;
1.106 markus 1319:
1320: /* XXX should be pre-session */
1321: ssh_init_forwarding();
1322:
1.344 djm 1323: /* Start listening for multiplex clients */
1324: muxserver_listen();
1325:
1326: /*
1327: * If we are in control persist mode, then prepare to background
1328: * ourselves and have a foreground client attach as a control
1329: * slave. NB. we must save copies of the flags that we override for
1330: * the backgrounding, since we defer attachment of the slave until
1331: * after the connection is fully established (in particular,
1332: * async rfwd replies have been received for ExitOnForwardFailure).
1333: */
1334: if (options.control_persist && muxserver_sock != -1) {
1335: ostdin_null_flag = stdin_null_flag;
1336: ono_shell_flag = no_shell_flag;
1337: ono_tty_flag = no_tty_flag;
1338: otty_flag = tty_flag;
1339: stdin_null_flag = 1;
1340: no_shell_flag = 1;
1341: no_tty_flag = 1;
1342: tty_flag = 0;
1343: if (!fork_after_authentication_flag)
1344: need_controlpersist_detach = 1;
1345: fork_after_authentication_flag = 1;
1346: }
1347:
1.143 markus 1348: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1349: id = ssh_session2_open();
1.314 djm 1350:
1351: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1352: if (options.control_master == SSHCTL_MASTER_NO &&
1353: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1354: debug("Requesting no-more-sessions@openssh.com");
1355: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1356: packet_put_cstring("no-more-sessions@openssh.com");
1357: packet_put_char(0);
1358: packet_send();
1359: }
1.255 reyk 1360:
1361: /* Execute a local command */
1362: if (options.local_command != NULL &&
1363: options.permit_local_command)
1364: ssh_local_cmd(options.local_command);
1.301 djm 1365:
1.342 djm 1366: /*
1367: * If requested and we are not interested in replies to remote
1368: * forwarding requests, then let ssh continue in the background.
1369: */
1.344 djm 1370: if (fork_after_authentication_flag) {
1371: if (options.exit_on_forward_failure &&
1372: options.num_remote_forwards > 0) {
1373: debug("deferring postauth fork until remote forward "
1374: "confirmation received");
1375: } else
1376: fork_postauth();
1.318 djm 1377: }
1.327 andreas 1378:
1379: if (options.use_roaming)
1380: request_roaming();
1.31 markus 1381:
1.119 stevesk 1382: return client_loop(tty_flag, tty_flag ?
1383: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1384: }
1385:
1.126 itojun 1386: static void
1.104 markus 1387: load_public_identity_files(void)
1388: {
1.275 djm 1389: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1390: char *pwdir = NULL, *pwname = NULL;
1.167 markus 1391: int i = 0;
1.104 markus 1392: Key *public;
1.275 djm 1393: struct passwd *pw;
1.335 djm 1394: u_int n_ids;
1395: char *identity_files[SSH_MAX_IDENTITY_FILES];
1396: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.333 markus 1397: #ifdef ENABLE_PKCS11
1.167 markus 1398: Key **keys;
1.333 markus 1399: int nkeys;
1.335 djm 1400: #endif /* PKCS11 */
1.104 markus 1401:
1.335 djm 1402: n_ids = 0;
1403: bzero(identity_files, sizeof(identity_files));
1404: bzero(identity_keys, sizeof(identity_keys));
1405:
1406: #ifdef ENABLE_PKCS11
1.333 markus 1407: if (options.pkcs11_provider != NULL &&
1.167 markus 1408: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1409: (pkcs11_init(!options.batch_mode) == 0) &&
1410: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1411: &keys)) > 0) {
1412: for (i = 0; i < nkeys; i++) {
1.335 djm 1413: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1414: key_free(keys[i]);
1415: continue;
1416: }
1417: identity_keys[n_ids] = keys[i];
1418: identity_files[n_ids] =
1.333 markus 1419: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 1420: n_ids++;
1.167 markus 1421: }
1422: xfree(keys);
1.127 markus 1423: }
1.333 markus 1424: #endif /* ENABLE_PKCS11 */
1.275 djm 1425: if ((pw = getpwuid(original_real_uid)) == NULL)
1426: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 1427: pwname = xstrdup(pw->pw_name);
1428: pwdir = xstrdup(pw->pw_dir);
1.275 djm 1429: if (gethostname(thishost, sizeof(thishost)) == -1)
1430: fatal("load_public_identity_files: gethostname: %s",
1431: strerror(errno));
1.335 djm 1432: for (i = 0; i < options.num_identity_files; i++) {
1433: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1434: xfree(options.identity_files[i]);
1435: continue;
1436: }
1.275 djm 1437: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1438: original_real_uid);
1.306 deraadt 1439: filename = percent_expand(cp, "d", pwdir,
1440: "u", pwname, "l", thishost, "h", host,
1.275 djm 1441: "r", options.user, (char *)NULL);
1442: xfree(cp);
1.131 millert 1443: public = key_load_public(filename, NULL);
1444: debug("identity file %s type %d", filename,
1445: public ? public->type : -1);
1446: xfree(options.identity_files[i]);
1.335 djm 1447: identity_files[n_ids] = filename;
1448: identity_keys[n_ids] = public;
1449:
1450: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1451: continue;
1452:
1453: /* Try to add the certificate variant too */
1454: xasprintf(&cp, "%s-cert", filename);
1455: public = key_load_public(cp, NULL);
1456: debug("identity file %s type %d", cp,
1457: public ? public->type : -1);
1458: if (public == NULL) {
1459: xfree(cp);
1460: continue;
1461: }
1462: if (!key_is_cert(public)) {
1463: debug("%s: key %s type %s is not a certificate",
1464: __func__, cp, key_type(public));
1465: key_free(public);
1466: xfree(cp);
1467: continue;
1468: }
1469: identity_keys[n_ids] = public;
1470: /* point to the original path, most likely the private key */
1471: identity_files[n_ids] = xstrdup(filename);
1472: n_ids++;
1473: }
1474: options.num_identity_files = n_ids;
1475: memcpy(options.identity_files, identity_files, sizeof(identity_files));
1476: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1477:
1.306 deraadt 1478: bzero(pwname, strlen(pwname));
1.307 dtucker 1479: xfree(pwname);
1.306 deraadt 1480: bzero(pwdir, strlen(pwdir));
1.307 dtucker 1481: xfree(pwdir);
1.214 djm 1482: }
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