Annotation of src/usr.bin/ssh/ssh.c, Revision 1.384
1.384 ! djm 1: /* $OpenBSD: ssh.c,v 1.383 2013/10/14 23:28:23 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>
1.352 djm 52: #include <sys/wait.h>
1.258 stevesk 53:
1.265 stevesk 54: #include <ctype.h>
1.285 stevesk 55: #include <errno.h>
1.281 stevesk 56: #include <fcntl.h>
1.286 stevesk 57: #include <netdb.h>
1.258 stevesk 58: #include <paths.h>
1.279 stevesk 59: #include <pwd.h>
1.263 stevesk 60: #include <signal.h>
1.287 stevesk 61: #include <stddef.h>
1.291 stevesk 62: #include <stdio.h>
1.290 stevesk 63: #include <stdlib.h>
1.289 stevesk 64: #include <string.h>
1.288 stevesk 65: #include <unistd.h>
1.49 markus 66:
67: #include <openssl/evp.h>
1.72 markus 68: #include <openssl/err.h>
1.1 deraadt 69:
1.293 deraadt 70: #include "xmalloc.h"
1.84 markus 71: #include "ssh.h"
72: #include "ssh1.h"
73: #include "ssh2.h"
1.341 djm 74: #include "canohost.h"
1.84 markus 75: #include "compat.h"
76: #include "cipher.h"
1.1 deraadt 77: #include "packet.h"
78: #include "buffer.h"
1.123 markus 79: #include "channels.h"
1.49 markus 80: #include "key.h"
1.58 markus 81: #include "authfd.h"
1.49 markus 82: #include "authfile.h"
1.83 markus 83: #include "pathnames.h"
1.214 djm 84: #include "dispatch.h"
1.81 markus 85: #include "clientloop.h"
1.84 markus 86: #include "log.h"
87: #include "readconf.h"
88: #include "sshconnect.h"
89: #include "misc.h"
1.95 markus 90: #include "kex.h"
91: #include "mac.h"
1.213 deraadt 92: #include "sshpty.h"
1.212 djm 93: #include "match.h"
1.214 djm 94: #include "msg.h"
1.225 dtucker 95: #include "uidswap.h"
1.327 andreas 96: #include "roaming.h"
1.278 stevesk 97: #include "version.h"
1.49 markus 98:
1.333 markus 99: #ifdef ENABLE_PKCS11
100: #include "ssh-pkcs11.h"
1.137 jakob 101: #endif
1.127 markus 102:
1.49 markus 103: extern char *__progname;
1.1 deraadt 104:
1.316 djm 105: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 106: int debug_flag = 0;
107:
1.359 djm 108: /* Flag indicating whether a tty should be requested */
1.1 deraadt 109: int tty_flag = 0;
110:
1.45 markus 111: /* don't exec a shell */
112: int no_shell_flag = 0;
113:
1.33 markus 114: /*
115: * Flag indicating that nothing should be read from stdin. This can be set
116: * on the command line.
117: */
1.1 deraadt 118: int stdin_null_flag = 0;
119:
1.33 markus 120: /*
1.344 djm 121: * Flag indicating that the current process should be backgrounded and
122: * a new slave launched in the foreground for ControlPersist.
123: */
124: int need_controlpersist_detach = 0;
125:
126: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 127: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 128:
129: /*
1.33 markus 130: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 131: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 132: * background.
133: */
1.1 deraadt 134: int fork_after_authentication_flag = 0;
135:
1.331 dtucker 136: /* forward stdio to remote host and port */
137: char *stdio_forward_host = NULL;
138: int stdio_forward_port = 0;
139:
1.33 markus 140: /*
141: * General data structure for command line options and options configurable
142: * in configuration files. See readconf.h.
143: */
1.1 deraadt 144: Options options;
145:
1.139 markus 146: /* optional user configfile */
147: char *config = NULL;
148:
1.33 markus 149: /*
150: * Name of the host we are connecting to. This is the name given on the
151: * command line, or the HostName specified for the user-supplied name in a
152: * configuration file.
153: */
1.1 deraadt 154: char *host;
155:
1.22 provos 156: /* socket address the host resolves to */
1.37 markus 157: struct sockaddr_storage hostaddr;
1.1 deraadt 158:
1.112 markus 159: /* Private host keys. */
1.173 markus 160: Sensitive sensitive_data;
1.1 deraadt 161:
1.10 dugsong 162: /* Original real UID. */
163: uid_t original_real_uid;
1.177 markus 164: uid_t original_effective_uid;
1.1 deraadt 165:
1.45 markus 166: /* command to be executed */
167: Buffer command;
168:
1.85 djm 169: /* Should we execute a command or invoke a subsystem? */
170: int subsystem_flag = 0;
171:
1.170 markus 172: /* # of replies received for global requests */
1.315 djm 173: static int remote_forward_confirms_received = 0;
1.170 markus 174:
1.313 djm 175: /* mux.c */
176: extern int muxserver_sock;
177: extern u_int muxclient_command;
178:
1.186 djm 179:
1.1 deraadt 180: /* Prints a help message to the user. This function never returns. */
181:
1.126 itojun 182: static void
1.93 itojun 183: usage(void)
1.1 deraadt 184: {
1.208 markus 185: fprintf(stderr,
1.321 jmc 186: "usage: ssh [-1246AaCfgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.375 dtucker 187: " [-D [bind_address:]port] [-E log_file] [-e escape_char]\n"
188: " [-F configfile] [-I pkcs11] [-i identity_file]\n"
1.377 djm 189: " [-L [bind_address:]port:host:hostport] [-Q protocol_feature]\n"
1.232 djm 190: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
1.233 jmc 191: " [-R [bind_address:]port:host:hostport] [-S ctl_path]\n"
1.331 dtucker 192: " [-W host:port] [-w local_tun[:remote_tun]]\n"
193: " [user@]hostname [command]\n"
1.208 markus 194: );
1.257 dtucker 195: exit(255);
1.1 deraadt 196: }
197:
1.126 itojun 198: static int ssh_session(void);
199: static int ssh_session2(void);
200: static void load_public_identity_files(void);
1.352 djm 201: static void main_sigchld_handler(int);
1.312 djm 202:
203: /* from muxclient.c */
204: void muxclient(const char *);
205: void muxserver_listen(void);
1.45 markus 206:
1.361 djm 207: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
208: static void
209: tilde_expand_paths(char **paths, u_int num_paths)
210: {
211: u_int i;
212: char *cp;
213:
214: for (i = 0; i < num_paths; i++) {
215: cp = tilde_expand_filename(paths[i], original_real_uid);
1.378 djm 216: free(paths[i]);
1.361 djm 217: paths[i] = cp;
218: }
219: }
220:
1.32 deraadt 221: /*
222: * Main program for the ssh client.
223: */
1.2 provos 224: int
225: main(int ac, char **av)
1.1 deraadt 226: {
1.326 dtucker 227: int i, r, opt, exit_status, use_syslog;
1.375 dtucker 228: char *p, *cp, *line, *argv0, buf[MAXPATHLEN], *host_arg, *logfile;
1.358 djm 229: char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
1.31 markus 230: struct stat st;
1.98 markus 231: struct passwd *pw;
1.382 djm 232: int timeout_ms;
1.144 stevesk 233: extern int optind, optreset;
234: extern char *optarg;
1.232 djm 235: Forward fwd;
1.250 djm 236:
237: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
238: sanitise_stdfd();
1.31 markus 239:
1.33 markus 240: /*
1.346 djm 241: * Discard other fds that are hanging around. These can cause problem
242: * with backgrounded ssh processes started by ControlPersist.
243: */
244: closefrom(STDERR_FILENO + 1);
245:
246: /*
1.33 markus 247: * Save the original real uid. It will be needed later (uid-swapping
248: * may clobber the real uid).
249: */
1.31 markus 250: original_real_uid = getuid();
251: original_effective_uid = geteuid();
252:
1.184 stevesk 253: /*
254: * Use uid-swapping to give up root privileges for the duration of
255: * option processing. We will re-instantiate the rights when we are
256: * ready to create the privileged port, and will permanently drop
257: * them when the port has been created (actually, when the connection
258: * has been made, as we may need to create the port several times).
259: */
260: PRIV_END;
261:
1.31 markus 262: /* If we are installed setuid root be careful to not drop core. */
263: if (original_real_uid != original_effective_uid) {
264: struct rlimit rlim;
265: rlim.rlim_cur = rlim.rlim_max = 0;
266: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
267: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 268: }
1.107 markus 269: /* Get user data. */
270: pw = getpwuid(original_real_uid);
271: if (!pw) {
1.380 djm 272: logit("No user exists for uid %lu", (u_long)original_real_uid);
1.257 dtucker 273: exit(255);
1.107 markus 274: }
275: /* Take a copy of the returned structure. */
276: pw = pwcopy(pw);
1.31 markus 277:
1.33 markus 278: /*
279: * Set our umask to something reasonable, as some files are created
280: * with the default umask. This will make them world-readable but
281: * writable only by the owner, which is ok for all files for which we
282: * don't set the modes explicitly.
283: */
1.31 markus 284: umask(022);
285:
1.316 djm 286: /*
287: * Initialize option structure to indicate that no values have been
288: * set.
289: */
1.31 markus 290: initialize_options(&options);
291:
292: /* Parse command-line arguments. */
293: host = NULL;
1.320 djm 294: use_syslog = 0;
1.375 dtucker 295: logfile = NULL;
1.325 markus 296: argv0 = av[0];
1.31 markus 297:
1.266 djm 298: again:
1.316 djm 299: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.376 djm 300: "ACD:E:F:I:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
1.31 markus 301: switch (opt) {
1.91 jakob 302: case '1':
303: options.protocol = SSH_PROTO_1;
304: break;
1.47 markus 305: case '2':
306: options.protocol = SSH_PROTO_2;
307: break;
1.37 markus 308: case '4':
1.196 djm 309: options.address_family = AF_INET;
1.37 markus 310: break;
311: case '6':
1.196 djm 312: options.address_family = AF_INET6;
1.37 markus 313: break;
1.31 markus 314: case 'n':
315: stdin_null_flag = 1;
316: break;
317: case 'f':
318: fork_after_authentication_flag = 1;
319: stdin_null_flag = 1;
320: break;
321: case 'x':
322: options.forward_x11 = 0;
323: break;
324: case 'X':
325: options.forward_x11 = 1;
326: break;
1.320 djm 327: case 'y':
328: use_syslog = 1;
329: break;
1.375 dtucker 330: case 'E':
331: logfile = xstrdup(optarg);
332: break;
1.202 markus 333: case 'Y':
334: options.forward_x11 = 1;
335: options.forward_x11_trusted = 1;
336: break;
1.31 markus 337: case 'g':
338: options.gateway_ports = 1;
339: break;
1.229 djm 340: case 'O':
1.332 djm 341: if (stdio_forward_host != NULL)
342: fatal("Cannot specify multiplexing "
343: "command with -W");
344: else if (muxclient_command != 0)
345: fatal("Multiplexing command already specified");
1.229 djm 346: if (strcmp(optarg, "check") == 0)
1.312 djm 347: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 348: else if (strcmp(optarg, "forward") == 0)
349: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 350: else if (strcmp(optarg, "exit") == 0)
1.312 djm 351: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 352: else if (strcmp(optarg, "stop") == 0)
353: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 354: else if (strcmp(optarg, "cancel") == 0)
355: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.229 djm 356: else
357: fatal("Invalid multiplex command.");
358: break;
1.183 stevesk 359: case 'P': /* deprecated */
1.31 markus 360: options.use_privileged_port = 0;
1.376 djm 361: break;
362: case 'Q': /* deprecated */
363: cp = NULL;
364: if (strcasecmp(optarg, "cipher") == 0)
365: cp = cipher_alg_list();
366: else if (strcasecmp(optarg, "mac") == 0)
367: cp = mac_alg_list();
368: else if (strcasecmp(optarg, "kex") == 0)
369: cp = kex_alg_list();
370: else if (strcasecmp(optarg, "key") == 0)
371: cp = key_alg_list();
372: if (cp == NULL)
373: fatal("Unsupported query \"%s\"", optarg);
374: printf("%s\n", cp);
375: free(cp);
376: exit(0);
1.31 markus 377: break;
378: case 'a':
379: options.forward_agent = 0;
1.53 markus 380: break;
381: case 'A':
382: options.forward_agent = 1;
1.31 markus 383: break;
384: case 'k':
1.204 dtucker 385: options.gss_deleg_creds = 0;
1.297 djm 386: break;
387: case 'K':
388: options.gss_authentication = 1;
389: options.gss_deleg_creds = 1;
1.31 markus 390: break;
391: case 'i':
392: if (stat(optarg, &st) < 0) {
1.128 fgsch 393: fprintf(stderr, "Warning: Identity file %s "
1.231 otto 394: "not accessible: %s.\n", optarg,
395: strerror(errno));
1.31 markus 396: break;
397: }
1.371 dtucker 398: add_identity_file(&options, NULL, optarg, 1);
1.31 markus 399: break;
1.127 markus 400: case 'I':
1.333 markus 401: #ifdef ENABLE_PKCS11
402: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 403: #else
1.333 markus 404: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 405: #endif
1.127 markus 406: break;
1.31 markus 407: case 't':
1.359 djm 408: if (options.request_tty == REQUEST_TTY_YES)
409: options.request_tty = REQUEST_TTY_FORCE;
410: else
411: options.request_tty = REQUEST_TTY_YES;
1.31 markus 412: break;
413: case 'v':
1.197 markus 414: if (debug_flag == 0) {
1.66 markus 415: debug_flag = 1;
416: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 417: } else {
418: if (options.log_level < SYSLOG_LEVEL_DEBUG3)
419: options.log_level++;
420: }
1.375 dtucker 421: break;
1.31 markus 422: case 'V':
1.209 markus 423: fprintf(stderr, "%s, %s\n",
424: SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 425: if (opt == 'V')
426: exit(0);
427: break;
1.255 reyk 428: case 'w':
1.256 reyk 429: if (options.tun_open == -1)
430: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 431: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 432: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 433: fprintf(stderr,
434: "Bad tun device '%s'\n", optarg);
1.257 dtucker 435: exit(255);
1.255 reyk 436: }
437: break;
1.331 dtucker 438: case 'W':
1.332 djm 439: if (stdio_forward_host != NULL)
440: fatal("stdio forward already specified");
441: if (muxclient_command != 0)
442: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 443: if (parse_forward(&fwd, optarg, 1, 0)) {
444: stdio_forward_host = fwd.listen_host;
445: stdio_forward_port = fwd.listen_port;
1.378 djm 446: free(fwd.connect_host);
1.331 dtucker 447: } else {
448: fprintf(stderr,
449: "Bad stdio forwarding specification '%s'\n",
450: optarg);
451: exit(255);
452: }
1.359 djm 453: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 454: no_shell_flag = 1;
455: options.clear_forwardings = 1;
456: options.exit_on_forward_failure = 1;
457: break;
1.31 markus 458: case 'q':
459: options.log_level = SYSLOG_LEVEL_QUIET;
460: break;
461: case 'e':
462: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 463: (u_char) optarg[1] >= 64 &&
464: (u_char) optarg[1] < 128)
1.78 markus 465: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 466: else if (strlen(optarg) == 1)
1.78 markus 467: options.escape_char = (u_char) optarg[0];
1.31 markus 468: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 469: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 470: else {
1.128 fgsch 471: fprintf(stderr, "Bad escape character '%s'.\n",
472: optarg);
1.257 dtucker 473: exit(255);
1.31 markus 474: }
475: break;
476: case 'c':
1.49 markus 477: if (ciphers_valid(optarg)) {
478: /* SSH2 only */
479: options.ciphers = xstrdup(optarg);
1.224 markus 480: options.cipher = SSH_CIPHER_INVALID;
1.49 markus 481: } else {
482: /* SSH1 only */
1.74 markus 483: options.cipher = cipher_number(optarg);
484: if (options.cipher == -1) {
1.128 fgsch 485: fprintf(stderr,
486: "Unknown cipher type '%s'\n",
487: optarg);
1.257 dtucker 488: exit(255);
1.49 markus 489: }
1.128 fgsch 490: if (options.cipher == SSH_CIPHER_3DES)
1.74 markus 491: options.ciphers = "3des-cbc";
1.128 fgsch 492: else if (options.cipher == SSH_CIPHER_BLOWFISH)
1.74 markus 493: options.ciphers = "blowfish-cbc";
1.128 fgsch 494: else
1.74 markus 495: options.ciphers = (char *)-1;
1.95 markus 496: }
497: break;
498: case 'm':
499: if (mac_valid(optarg))
500: options.macs = xstrdup(optarg);
501: else {
1.128 fgsch 502: fprintf(stderr, "Unknown mac type '%s'\n",
503: optarg);
1.257 dtucker 504: exit(255);
1.31 markus 505: }
506: break;
1.214 djm 507: case 'M':
1.242 djm 508: if (options.control_master == SSHCTL_MASTER_YES)
509: options.control_master = SSHCTL_MASTER_ASK;
510: else
511: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 512: break;
1.31 markus 513: case 'p':
1.113 stevesk 514: options.port = a2port(optarg);
1.323 djm 515: if (options.port <= 0) {
1.109 markus 516: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 517: exit(255);
1.109 markus 518: }
1.31 markus 519: break;
520: case 'l':
521: options.user = optarg;
522: break;
1.141 stevesk 523:
524: case 'L':
1.324 djm 525: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 526: add_local_forward(&options, &fwd);
527: else {
1.128 fgsch 528: fprintf(stderr,
1.232 djm 529: "Bad local forwarding specification '%s'\n",
1.128 fgsch 530: optarg);
1.257 dtucker 531: exit(255);
1.31 markus 532: }
1.232 djm 533: break;
534:
535: case 'R':
1.324 djm 536: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 537: add_remote_forward(&options, &fwd);
538: } else {
1.128 fgsch 539: fprintf(stderr,
1.232 djm 540: "Bad remote forwarding specification "
541: "'%s'\n", optarg);
1.257 dtucker 542: exit(255);
1.31 markus 543: }
544: break;
1.108 markus 545:
546: case 'D':
1.324 djm 547: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 548: add_local_forward(&options, &fwd);
1.232 djm 549: } else {
1.322 stevesk 550: fprintf(stderr,
551: "Bad dynamic forwarding specification "
552: "'%s'\n", optarg);
1.257 dtucker 553: exit(255);
1.109 markus 554: }
1.108 markus 555: break;
556:
1.31 markus 557: case 'C':
558: options.compression = 1;
559: break;
1.45 markus 560: case 'N':
561: no_shell_flag = 1;
1.359 djm 562: options.request_tty = REQUEST_TTY_NO;
1.45 markus 563: break;
564: case 'T':
1.359 djm 565: options.request_tty = REQUEST_TTY_NO;
1.45 markus 566: break;
1.31 markus 567: case 'o':
1.205 markus 568: line = xstrdup(optarg);
1.382 djm 569: if (process_config_line(&options, pw, host ? host : "",
570: line, "command-line", 0, NULL, SSHCONF_USERCONF)
1.372 dtucker 571: != 0)
1.257 dtucker 572: exit(255);
1.378 djm 573: free(line);
1.31 markus 574: break;
1.85 djm 575: case 's':
576: subsystem_flag = 1;
1.117 markus 577: break;
1.214 djm 578: case 'S':
579: if (options.control_path != NULL)
580: free(options.control_path);
581: options.control_path = xstrdup(optarg);
582: break;
1.117 markus 583: case 'b':
584: options.bind_address = optarg;
1.85 djm 585: break;
1.139 markus 586: case 'F':
587: config = optarg;
588: break;
1.31 markus 589: default:
590: usage();
1.1 deraadt 591: }
1.31 markus 592: }
593:
1.128 fgsch 594: ac -= optind;
595: av += optind;
596:
1.329 guenther 597: if (ac > 0 && !host) {
1.188 markus 598: if (strrchr(*av, '@')) {
1.128 fgsch 599: p = xstrdup(*av);
1.188 markus 600: cp = strrchr(p, '@');
1.128 fgsch 601: if (cp == NULL || cp == p)
602: usage();
603: options.user = p;
604: *cp = '\0';
605: host = ++cp;
606: } else
607: host = *av;
1.189 millert 608: if (ac > 1) {
609: optind = optreset = 1;
1.128 fgsch 610: goto again;
611: }
1.189 millert 612: ac--, av++;
1.128 fgsch 613: }
614:
1.31 markus 615: /* Check that we got a host name. */
616: if (!host)
617: usage();
618:
1.350 djm 619: OpenSSL_add_all_algorithms();
1.72 markus 620: ERR_load_crypto_strings();
1.31 markus 621:
622: /* Initialize the command to execute on remote host. */
623: buffer_init(&command);
1.1 deraadt 624:
1.33 markus 625: /*
626: * Save the command to execute on the remote host in a buffer. There
627: * is no limit on the length of the command, except by the maximum
628: * packet size. Also sets the tty flag if there is no command.
629: */
1.128 fgsch 630: if (!ac) {
1.31 markus 631: /* No command specified - execute shell on a tty. */
1.85 djm 632: if (subsystem_flag) {
1.128 fgsch 633: fprintf(stderr,
634: "You must specify a subsystem to invoke.\n");
1.85 djm 635: usage();
636: }
1.31 markus 637: } else {
1.128 fgsch 638: /* A command has been specified. Store it into the buffer. */
639: for (i = 0; i < ac; i++) {
640: if (i)
1.31 markus 641: buffer_append(&command, " ", 1);
642: buffer_append(&command, av[i], strlen(av[i]));
643: }
644: }
645:
646: /* Cannot fork to background if no command. */
1.316 djm 647: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
648: !no_shell_flag)
649: fatal("Cannot fork into background without a command "
650: "to execute.");
1.31 markus 651:
1.101 markus 652: /*
653: * Initialize "log" output. Since we are the client all output
1.375 dtucker 654: * goes to stderr unless otherwise specified by -y or -E.
1.101 markus 655: */
1.375 dtucker 656: if (use_syslog && logfile != NULL)
657: fatal("Can't specify both -y and -E");
658: if (logfile != NULL) {
659: log_redirect_stderr_to(logfile);
1.378 djm 660: free(logfile);
1.375 dtucker 661: }
1.325 markus 662: log_init(argv0,
1.316 djm 663: options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level,
1.320 djm 664: SYSLOG_FACILITY_USER, !use_syslog);
1.375 dtucker 665:
666: if (debug_flag)
667: logit("%s, %s", SSH_VERSION, SSLeay_version(SSLEAY_VERSION));
1.31 markus 668:
1.139 markus 669: /*
670: * Read per-user configuration file. Ignore the system wide config
671: * file if the user specifies a config file on the command line.
672: */
673: if (config != NULL) {
1.374 djm 674: if (strcasecmp(config, "none") != 0 &&
1.382 djm 675: !read_config_file(config, pw, host, &options,
676: SSHCONF_USERCONF))
1.142 stevesk 677: fatal("Can't open user config file %.100s: "
678: "%.100s", config, strerror(errno));
1.295 stevesk 679: } else {
1.326 dtucker 680: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
1.139 markus 681: _PATH_SSH_USER_CONFFILE);
1.326 dtucker 682: if (r > 0 && (size_t)r < sizeof(buf))
1.382 djm 683: (void)read_config_file(buf, pw, host, &options,
1.372 dtucker 684: SSHCONF_CHECKPERM|SSHCONF_USERCONF);
1.139 markus 685:
1.364 djm 686: /* Read systemwide configuration file after user config. */
1.382 djm 687: (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, host,
1.210 djm 688: &options, 0);
1.139 markus 689: }
1.31 markus 690:
691: /* Fill configuration defaults. */
692: fill_default_options(&options);
693:
1.196 djm 694: channel_set_af(options.address_family);
695:
1.383 djm 696: /* Tidy and check options */
697: if (options.host_key_alias != NULL)
698: lowercase(options.host_key_alias);
699: if (options.proxy_command != NULL &&
700: strcmp(options.proxy_command, "-") == 0 &&
701: options.proxy_use_fdpass)
702: fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
703:
1.31 markus 704: /* reinit */
1.325 markus 705: log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog);
1.370 djm 706:
707: if (options.request_tty == REQUEST_TTY_YES ||
708: options.request_tty == REQUEST_TTY_FORCE)
709: tty_flag = 1;
710:
711: /* Allocate a tty by default if no command specified. */
712: if (buffer_len(&command) == 0)
713: tty_flag = options.request_tty != REQUEST_TTY_NO;
714:
715: /* Force no tty */
716: if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0)
717: tty_flag = 0;
718: /* Do not allocate a tty if stdin is not a tty. */
719: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
720: options.request_tty != REQUEST_TTY_FORCE) {
721: if (tty_flag)
722: logit("Pseudo-terminal will not be allocated because "
723: "stdin is not a terminal.");
724: tty_flag = 0;
725: }
1.31 markus 726:
727: if (options.user == NULL)
728: options.user = xstrdup(pw->pw_name);
729:
1.317 dtucker 730: /* Get default port if port has not been set. */
1.382 djm 731: if (options.port == 0)
732: options.port = default_ssh_port();
1.317 dtucker 733:
1.356 djm 734: /* preserve host name given on command line for %n expansion */
735: host_arg = host;
1.343 djm 736: if (options.hostname != NULL) {
737: host = percent_expand(options.hostname,
738: "h", host, (char *)NULL);
739: }
740:
1.358 djm 741: if (gethostname(thishost, sizeof(thishost)) == -1)
742: fatal("gethostname: %s", strerror(errno));
743: strlcpy(shorthost, thishost, sizeof(shorthost));
744: shorthost[strcspn(thishost, ".")] = '\0';
745: snprintf(portstr, sizeof(portstr), "%d", options.port);
746:
1.317 dtucker 747: if (options.local_command != NULL) {
748: debug3("expanding LocalCommand: %s", options.local_command);
749: cp = options.local_command;
750: options.local_command = percent_expand(cp, "d", pw->pw_dir,
1.356 djm 751: "h", host, "l", thishost, "n", host_arg, "r", options.user,
1.358 djm 752: "p", portstr, "u", pw->pw_name, "L", shorthost,
753: (char *)NULL);
1.317 dtucker 754: debug3("expanded LocalCommand: %s", options.local_command);
1.378 djm 755: free(cp);
1.304 dtucker 756: }
1.31 markus 757:
1.214 djm 758: if (options.control_path != NULL) {
1.241 djm 759: cp = tilde_expand_filename(options.control_path,
760: original_real_uid);
1.378 djm 761: free(options.control_path);
1.358 djm 762: options.control_path = percent_expand(cp, "h", host,
763: "l", thishost, "n", host_arg, "r", options.user,
764: "p", portstr, "u", pw->pw_name, "L", shorthost,
765: (char *)NULL);
1.378 djm 766: free(cp);
1.214 djm 767: }
1.312 djm 768: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 769: fatal("No ControlPath specified for \"-O\" command");
1.242 djm 770: if (options.control_path != NULL)
1.312 djm 771: muxclient(options.control_path);
1.214 djm 772:
1.303 djm 773: timeout_ms = options.connection_timeout * 1000;
774:
1.77 markus 775: /* Open a connection to the remote host. */
1.203 djm 776: if (ssh_connect(host, &hostaddr, options.port,
1.303 djm 777: options.address_family, options.connection_attempts, &timeout_ms,
1.384 ! djm 778: options.tcp_keep_alive,
1.177 markus 779: original_effective_uid == 0 && options.use_privileged_port,
1.179 markus 780: options.proxy_command) != 0)
1.257 dtucker 781: exit(255);
1.31 markus 782:
1.303 djm 783: if (timeout_ms > 0)
784: debug3("timeout: %d ms remain after connect", timeout_ms);
785:
1.33 markus 786: /*
787: * If we successfully made the connection, load the host private key
788: * in case we will need it later for combined rsa-rhosts
789: * authentication. This must be done before releasing extra
790: * privileges, because the file is only readable by root.
1.174 markus 791: * If we cannot access the private keys, load the public keys
792: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 793: */
1.112 markus 794: sensitive_data.nkeys = 0;
795: sensitive_data.keys = NULL;
1.173 markus 796: sensitive_data.external_keysign = 0;
1.178 markus 797: if (options.rhosts_rsa_authentication ||
798: options.hostbased_authentication) {
1.349 djm 799: sensitive_data.nkeys = 7;
1.274 deraadt 800: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 801: sizeof(Key));
1.177 markus 802:
803: PRIV_START;
1.112 markus 804: sensitive_data.keys[0] = key_load_private_type(KEY_RSA1,
1.276 dtucker 805: _PATH_HOST_KEY_FILE, "", NULL, NULL);
1.345 djm 806: sensitive_data.keys[1] = key_load_private_cert(KEY_DSA,
807: _PATH_HOST_DSA_KEY_FILE, "", NULL);
1.349 djm 808: sensitive_data.keys[2] = key_load_private_cert(KEY_ECDSA,
809: _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
810: sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1.345 djm 811: _PATH_HOST_RSA_KEY_FILE, "", NULL);
1.349 djm 812: sensitive_data.keys[4] = key_load_private_type(KEY_DSA,
1.276 dtucker 813: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.349 djm 814: sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
815: _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
816: sensitive_data.keys[6] = key_load_private_type(KEY_RSA,
1.276 dtucker 817: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.177 markus 818: PRIV_END;
1.173 markus 819:
1.181 markus 820: if (options.hostbased_authentication == 1 &&
821: sensitive_data.keys[0] == NULL &&
1.349 djm 822: sensitive_data.keys[4] == NULL &&
823: sensitive_data.keys[5] == NULL &&
824: sensitive_data.keys[6] == NULL) {
1.345 djm 825: sensitive_data.keys[1] = key_load_cert(
826: _PATH_HOST_DSA_KEY_FILE);
827: sensitive_data.keys[2] = key_load_cert(
1.349 djm 828: _PATH_HOST_ECDSA_KEY_FILE);
829: sensitive_data.keys[3] = key_load_cert(
1.345 djm 830: _PATH_HOST_RSA_KEY_FILE);
1.349 djm 831: sensitive_data.keys[4] = key_load_public(
1.173 markus 832: _PATH_HOST_DSA_KEY_FILE, NULL);
1.349 djm 833: sensitive_data.keys[5] = key_load_public(
834: _PATH_HOST_ECDSA_KEY_FILE, NULL);
835: sensitive_data.keys[6] = key_load_public(
1.173 markus 836: _PATH_HOST_RSA_KEY_FILE, NULL);
837: sensitive_data.external_keysign = 1;
838: }
1.31 markus 839: }
1.33 markus 840: /*
841: * Get rid of any extra privileges that we may have. We will no
842: * longer need them. Also, extra privileges could make it very hard
843: * to read identity files and other non-world-readable files from the
844: * user's home directory if it happens to be on a NFS volume where
845: * root is mapped to nobody.
846: */
1.225 dtucker 847: if (original_effective_uid == 0) {
848: PRIV_START;
849: permanently_set_uid(pw);
850: }
1.31 markus 851:
1.33 markus 852: /*
853: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 854: * directory if it doesn't already exist.
1.33 markus 855: */
1.367 djm 856: if (config == NULL) {
857: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
858: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
859: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
860: if (mkdir(buf, 0700) < 0)
861: error("Could not create directory '%.200s'.",
862: buf);
863: }
1.31 markus 864:
1.104 markus 865: /* load options.identity_files */
866: load_public_identity_files();
867:
868: /* Expand ~ in known host file names. */
1.361 djm 869: tilde_expand_paths(options.system_hostfiles,
870: options.num_system_hostfiles);
871: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 872:
873: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 874: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 875:
1.316 djm 876: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 877: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 878: options.port, pw, timeout_ms);
1.339 djm 879:
880: if (packet_connection_is_on_socket()) {
881: verbose("Authenticated to %s ([%s]:%d).", host,
882: get_remote_ipaddr(), get_remote_port());
883: } else {
884: verbose("Authenticated to %s (via proxy).", host);
885: }
1.31 markus 886:
1.112 markus 887: /* We no longer need the private host keys. Clear them now. */
888: if (sensitive_data.nkeys != 0) {
889: for (i = 0; i < sensitive_data.nkeys; i++) {
890: if (sensitive_data.keys[i] != NULL) {
891: /* Destroys contents safely */
892: debug3("clear hostkey %d", i);
893: key_free(sensitive_data.keys[i]);
894: sensitive_data.keys[i] = NULL;
895: }
896: }
1.378 djm 897: free(sensitive_data.keys);
1.134 markus 898: }
899: for (i = 0; i < options.num_identity_files; i++) {
1.378 djm 900: free(options.identity_files[i]);
901: options.identity_files[i] = NULL;
1.134 markus 902: if (options.identity_keys[i]) {
903: key_free(options.identity_keys[i]);
904: options.identity_keys[i] = NULL;
905: }
1.112 markus 906: }
1.31 markus 907:
1.45 markus 908: exit_status = compat20 ? ssh_session2() : ssh_session();
909: packet_close();
1.186 djm 910:
1.312 djm 911: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 912: unlink(options.control_path);
913:
1.353 djm 914: /* Kill ProxyCommand if it is running. */
915: ssh_kill_proxy_command();
1.186 djm 916:
1.45 markus 917: return exit_status;
918: }
919:
1.344 djm 920: static void
921: control_persist_detach(void)
922: {
923: pid_t pid;
1.346 djm 924: int devnull;
1.344 djm 925:
926: debug("%s: backgrounding master process", __func__);
927:
928: /*
929: * master (current process) into the background, and make the
930: * foreground process a client of the backgrounded master.
931: */
932: switch ((pid = fork())) {
933: case -1:
934: fatal("%s: fork: %s", __func__, strerror(errno));
935: case 0:
936: /* Child: master process continues mainloop */
937: break;
938: default:
939: /* Parent: set up mux slave to connect to backgrounded master */
940: debug2("%s: background process is %ld", __func__, (long)pid);
941: stdin_null_flag = ostdin_null_flag;
1.359 djm 942: options.request_tty = orequest_tty;
1.344 djm 943: tty_flag = otty_flag;
944: close(muxserver_sock);
945: muxserver_sock = -1;
1.351 markus 946: options.control_master = SSHCTL_MASTER_NO;
1.344 djm 947: muxclient(options.control_path);
948: /* muxclient() doesn't return on success. */
949: fatal("Failed to connect to new control master");
950: }
1.346 djm 951: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
952: error("%s: open(\"/dev/null\"): %s", __func__,
953: strerror(errno));
954: } else {
955: if (dup2(devnull, STDIN_FILENO) == -1 ||
956: dup2(devnull, STDOUT_FILENO) == -1)
957: error("%s: dup2: %s", __func__, strerror(errno));
958: if (devnull > STDERR_FILENO)
959: close(devnull);
960: }
1.381 djm 961: daemon(1, 1);
1.362 djm 962: setproctitle("%s [mux]", options.control_path);
1.344 djm 963: }
964:
965: /* Do fork() after authentication. Used by "ssh -f" */
966: static void
967: fork_postauth(void)
968: {
969: if (need_controlpersist_detach)
970: control_persist_detach();
971: debug("forking to background");
972: fork_after_authentication_flag = 0;
973: if (daemon(1, 1) < 0)
974: fatal("daemon() failed: %.200s", strerror(errno));
975: }
976:
1.315 djm 977: /* Callback for remote forward global requests */
978: static void
979: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
980: {
981: Forward *rfwd = (Forward *)ctxt;
982:
1.324 djm 983: /* XXX verbose() on failure? */
1.315 djm 984: debug("remote forward %s for: listen %d, connect %s:%d",
985: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
986: rfwd->listen_port, rfwd->connect_host, rfwd->connect_port);
1.366 markus 987: if (rfwd->listen_port == 0) {
988: if (type == SSH2_MSG_REQUEST_SUCCESS) {
989: rfwd->allocated_port = packet_get_int();
990: logit("Allocated port %u for remote forward to %s:%d",
991: rfwd->allocated_port,
992: rfwd->connect_host, rfwd->connect_port);
993: channel_update_permitted_opens(rfwd->handle,
994: rfwd->allocated_port);
995: } else {
996: channel_update_permitted_opens(rfwd->handle, -1);
997: }
1.324 djm 998: }
999:
1.315 djm 1000: if (type == SSH2_MSG_REQUEST_FAILURE) {
1001: if (options.exit_on_forward_failure)
1002: fatal("Error: remote port forwarding failed for "
1003: "listen port %d", rfwd->listen_port);
1004: else
1005: logit("Warning: remote port forwarding failed for "
1006: "listen port %d", rfwd->listen_port);
1007: }
1.318 djm 1008: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 1009: debug("All remote forwarding requests processed");
1.344 djm 1010: if (fork_after_authentication_flag)
1011: fork_postauth();
1.318 djm 1012: }
1.315 djm 1013: }
1014:
1.126 itojun 1015: static void
1.331 dtucker 1016: client_cleanup_stdio_fwd(int id, void *arg)
1017: {
1018: debug("stdio forwarding: done");
1019: cleanup_exit(0);
1020: }
1021:
1.368 djm 1022: static void
1023: ssh_init_stdio_forwarding(void)
1.331 dtucker 1024: {
1025: Channel *c;
1.332 djm 1026: int in, out;
1.331 dtucker 1027:
1.368 djm 1028: if (stdio_forward_host == NULL)
1029: return;
1.384 ! djm 1030: if (!compat20)
1.368 djm 1031: fatal("stdio forwarding require Protocol 2");
1032:
1033: debug3("%s: %s:%d", __func__, stdio_forward_host, stdio_forward_port);
1.332 djm 1034:
1.368 djm 1035: if ((in = dup(STDIN_FILENO)) < 0 ||
1036: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1037: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.368 djm 1038: if ((c = channel_connect_stdio_fwd(stdio_forward_host,
1039: stdio_forward_port, in, out)) == NULL)
1040: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.331 dtucker 1041: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1042: }
1043:
1044: static void
1.70 markus 1045: ssh_init_forwarding(void)
1046: {
1.86 markus 1047: int success = 0;
1.70 markus 1048: int i;
1.331 dtucker 1049:
1.70 markus 1050: /* Initiate local TCP/IP port forwardings. */
1051: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1052: debug("Local connections to %.200s:%d forwarded to remote "
1053: "address %.200s:%d",
1.234 deraadt 1054: (options.local_forwards[i].listen_host == NULL) ?
1055: (options.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1056: options.local_forwards[i].listen_host,
1057: options.local_forwards[i].listen_port,
1058: options.local_forwards[i].connect_host,
1059: options.local_forwards[i].connect_port);
1.158 markus 1060: success += channel_setup_local_fwd_listener(
1.232 djm 1061: options.local_forwards[i].listen_host,
1062: options.local_forwards[i].listen_port,
1063: options.local_forwards[i].connect_host,
1064: options.local_forwards[i].connect_port,
1.70 markus 1065: options.gateway_ports);
1066: }
1.283 markus 1067: if (i > 0 && success != i && options.exit_on_forward_failure)
1068: fatal("Could not request local forwarding.");
1.86 markus 1069: if (i > 0 && success == 0)
1070: error("Could not request local forwarding.");
1.70 markus 1071:
1072: /* Initiate remote TCP/IP port forwardings. */
1073: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1074: debug("Remote connections from %.200s:%d forwarded to "
1075: "local address %.200s:%d",
1.248 djm 1076: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1077: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1078: options.remote_forwards[i].listen_port,
1079: options.remote_forwards[i].connect_host,
1080: options.remote_forwards[i].connect_port);
1.366 markus 1081: options.remote_forwards[i].handle =
1082: channel_request_remote_forwarding(
1.232 djm 1083: options.remote_forwards[i].listen_host,
1084: options.remote_forwards[i].listen_port,
1085: options.remote_forwards[i].connect_host,
1.366 markus 1086: options.remote_forwards[i].connect_port);
1087: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1088: if (options.exit_on_forward_failure)
1089: fatal("Could not request remote forwarding.");
1090: else
1091: logit("Warning: Could not request remote "
1092: "forwarding.");
1.366 markus 1093: } else {
1094: client_register_global_confirm(ssh_confirm_remote_forward,
1095: &options.remote_forwards[i]);
1.283 markus 1096: }
1.70 markus 1097: }
1.301 djm 1098:
1099: /* Initiate tunnel forwarding. */
1100: if (options.tun_open != SSH_TUNMODE_NO) {
1101: if (client_request_tun_fwd(options.tun_open,
1102: options.tun_local, options.tun_remote) == -1) {
1103: if (options.exit_on_forward_failure)
1104: fatal("Could not request tunnel forwarding.");
1105: else
1106: error("Could not request tunnel forwarding.");
1107: }
1108: }
1.70 markus 1109: }
1110:
1.126 itojun 1111: static void
1.70 markus 1112: check_agent_present(void)
1113: {
1114: if (options.forward_agent) {
1.254 djm 1115: /* Clear agent forwarding if we don't have an agent. */
1.185 stevesk 1116: if (!ssh_agent_present())
1.70 markus 1117: options.forward_agent = 0;
1118: }
1119: }
1120:
1.126 itojun 1121: static int
1.45 markus 1122: ssh_session(void)
1123: {
1124: int type;
1125: int interactive = 0;
1126: int have_tty = 0;
1127: struct winsize ws;
1128: char *cp;
1.243 djm 1129: const char *display;
1.45 markus 1130:
1.31 markus 1131: /* Enable compression if requested. */
1132: if (options.compression) {
1.316 djm 1133: debug("Requesting compression at level %d.",
1134: options.compression_level);
1.31 markus 1135:
1.316 djm 1136: if (options.compression_level < 1 ||
1137: options.compression_level > 9)
1138: fatal("Compression level must be from 1 (fast) to "
1139: "9 (slow, best).");
1.31 markus 1140:
1141: /* Send the request. */
1142: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1143: packet_put_int(options.compression_level);
1144: packet_send();
1145: packet_write_wait();
1.156 markus 1146: type = packet_read();
1.31 markus 1147: if (type == SSH_SMSG_SUCCESS)
1148: packet_start_compression(options.compression_level);
1149: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1150: logit("Warning: Remote host refused compression.");
1.31 markus 1151: else
1.316 djm 1152: packet_disconnect("Protocol error waiting for "
1153: "compression response.");
1.31 markus 1154: }
1155: /* Allocate a pseudo tty if appropriate. */
1156: if (tty_flag) {
1157: debug("Requesting pty.");
1158:
1159: /* Start the packet. */
1160: packet_start(SSH_CMSG_REQUEST_PTY);
1161:
1162: /* Store TERM in the packet. There is no limit on the
1163: length of the string. */
1164: cp = getenv("TERM");
1165: if (!cp)
1166: cp = "";
1.124 markus 1167: packet_put_cstring(cp);
1.31 markus 1168:
1169: /* Store window size in the packet. */
1170: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1171: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1172: packet_put_int((u_int)ws.ws_row);
1173: packet_put_int((u_int)ws.ws_col);
1174: packet_put_int((u_int)ws.ws_xpixel);
1175: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1176:
1177: /* Store tty modes in the packet. */
1.115 stevesk 1178: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1179:
1180: /* Send the packet, and wait for it to leave. */
1181: packet_send();
1182: packet_write_wait();
1183:
1184: /* Read response from the server. */
1.156 markus 1185: type = packet_read();
1.43 markus 1186: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1187: interactive = 1;
1.45 markus 1188: have_tty = 1;
1.43 markus 1189: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1190: logit("Warning: Remote host failed or refused to "
1191: "allocate a pseudo tty.");
1.31 markus 1192: else
1.316 djm 1193: packet_disconnect("Protocol error waiting for pty "
1194: "request response.");
1.31 markus 1195: }
1196: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1197: display = getenv("DISPLAY");
1198: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1199: char *proto, *data;
1.50 markus 1200: /* Get reasonable local authentication information. */
1.243 djm 1201: client_x11_get_proto(display, options.xauth_location,
1.384 ! djm 1202: options.forward_x11_trusted,
1.340 djm 1203: options.forward_x11_timeout,
1204: &proto, &data);
1.50 markus 1205: /* Request forwarding with authentication spoofing. */
1.316 djm 1206: debug("Requesting X11 forwarding with authentication "
1207: "spoofing.");
1.363 djm 1208: x11_request_forwarding_with_spoofing(0, display, proto,
1209: data, 0);
1.31 markus 1210: /* Read response from the server. */
1.156 markus 1211: type = packet_read();
1.31 markus 1212: if (type == SSH_SMSG_SUCCESS) {
1213: interactive = 1;
1.50 markus 1214: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1215: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1216: } else {
1.316 djm 1217: packet_disconnect("Protocol error waiting for X11 "
1218: "forwarding");
1.50 markus 1219: }
1.31 markus 1220: }
1221: /* Tell the packet module whether this is an interactive session. */
1.354 djm 1222: packet_set_interactive(interactive,
1223: options.ip_qos_interactive, options.ip_qos_bulk);
1.31 markus 1224:
1225: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1226: check_agent_present();
1227:
1.31 markus 1228: if (options.forward_agent) {
1229: debug("Requesting authentication agent forwarding.");
1230: auth_request_forwarding();
1231:
1232: /* Read response from the server. */
1.156 markus 1233: type = packet_read();
1.155 markus 1234: packet_check_eom();
1.31 markus 1235: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1236: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1237: }
1238:
1.70 markus 1239: /* Initiate port forwardings. */
1.368 djm 1240: ssh_init_stdio_forwarding();
1.70 markus 1241: ssh_init_forwarding();
1.305 dtucker 1242:
1243: /* Execute a local command */
1244: if (options.local_command != NULL &&
1245: options.permit_local_command)
1246: ssh_local_cmd(options.local_command);
1.34 markus 1247:
1.318 djm 1248: /*
1249: * If requested and we are not interested in replies to remote
1250: * forwarding requests, then let ssh continue in the background.
1251: */
1.344 djm 1252: if (fork_after_authentication_flag) {
1253: if (options.exit_on_forward_failure &&
1254: options.num_remote_forwards > 0) {
1255: debug("deferring postauth fork until remote forward "
1256: "confirmation received");
1257: } else
1258: fork_postauth();
1.318 djm 1259: }
1.31 markus 1260:
1.33 markus 1261: /*
1262: * If a command was specified on the command line, execute the
1263: * command now. Otherwise request the server to start a shell.
1264: */
1.31 markus 1265: if (buffer_len(&command) > 0) {
1266: int len = buffer_len(&command);
1267: if (len > 900)
1268: len = 900;
1.316 djm 1269: debug("Sending command: %.*s", len,
1270: (u_char *)buffer_ptr(&command));
1.31 markus 1271: packet_start(SSH_CMSG_EXEC_CMD);
1272: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1273: packet_send();
1274: packet_write_wait();
1275: } else {
1276: debug("Requesting shell.");
1277: packet_start(SSH_CMSG_EXEC_SHELL);
1278: packet_send();
1279: packet_write_wait();
1280: }
1281:
1282: /* Enter the interactive session. */
1.119 stevesk 1283: return client_loop(have_tty, tty_flag ?
1284: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1285: }
1286:
1.214 djm 1287: /* request pty/x11/agent/tcpfwd/shell for channel */
1288: static void
1.337 djm 1289: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1290: {
1.215 djm 1291: extern char **environ;
1.243 djm 1292: const char *display;
1293: int interactive = tty_flag;
1.337 djm 1294:
1295: if (!success)
1296: return; /* No need for error message, channels code sens one */
1.215 djm 1297:
1.248 djm 1298: display = getenv("DISPLAY");
1.243 djm 1299: if (options.forward_x11 && display != NULL) {
1.150 stevesk 1300: char *proto, *data;
1.50 markus 1301: /* Get reasonable local authentication information. */
1.243 djm 1302: client_x11_get_proto(display, options.xauth_location,
1.340 djm 1303: options.forward_x11_trusted,
1304: options.forward_x11_timeout, &proto, &data);
1.50 markus 1305: /* Request forwarding with authentication spoofing. */
1.316 djm 1306: debug("Requesting X11 forwarding with authentication "
1307: "spoofing.");
1.363 djm 1308: x11_request_forwarding_with_spoofing(id, display, proto,
1309: data, 1);
1310: client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
1311: /* XXX exit_on_forward_failure */
1.80 markus 1312: interactive = 1;
1.50 markus 1313: }
1314:
1.70 markus 1315: check_agent_present();
1316: if (options.forward_agent) {
1317: debug("Requesting authentication agent forwarding.");
1318: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1319: packet_send();
1.212 djm 1320: }
1.369 dtucker 1321:
1322: /* Tell the packet module whether this is an interactive session. */
1323: packet_set_interactive(interactive,
1324: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1325:
1.214 djm 1326: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1327: NULL, fileno(stdin), &command, environ);
1.45 markus 1328: }
1329:
1.143 markus 1330: /* open new channel for a session */
1.126 itojun 1331: static int
1.143 markus 1332: ssh_session2_open(void)
1.45 markus 1333: {
1.118 markus 1334: Channel *c;
1335: int window, packetmax, in, out, err;
1.60 markus 1336:
1.62 markus 1337: if (stdin_null_flag) {
1.93 itojun 1338: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1339: } else {
1340: in = dup(STDIN_FILENO);
1341: }
1.60 markus 1342: out = dup(STDOUT_FILENO);
1343: err = dup(STDERR_FILENO);
1.45 markus 1344:
1345: if (in < 0 || out < 0 || err < 0)
1.62 markus 1346: fatal("dup() in/out/err failed");
1.45 markus 1347:
1.69 markus 1348: /* enable nonblocking unless tty */
1349: if (!isatty(in))
1350: set_nonblock(in);
1351: if (!isatty(out))
1352: set_nonblock(out);
1353: if (!isatty(err))
1354: set_nonblock(err);
1355:
1.65 markus 1356: window = CHAN_SES_WINDOW_DEFAULT;
1357: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1358: if (tty_flag) {
1359: window >>= 1;
1360: packetmax >>= 1;
1.45 markus 1361: }
1.118 markus 1362: c = channel_new(
1.45 markus 1363: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1364: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1365: "client-session", /*nonblock*/0);
1.45 markus 1366:
1.143 markus 1367: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1368:
1.122 markus 1369: channel_send_open(c->self);
1.143 markus 1370: if (!no_shell_flag)
1.310 djm 1371: channel_register_open_confirm(c->self,
1372: ssh_session2_setup, NULL);
1.106 markus 1373:
1.118 markus 1374: return c->self;
1.106 markus 1375: }
1376:
1.126 itojun 1377: static int
1.106 markus 1378: ssh_session2(void)
1379: {
1.143 markus 1380: int id = -1;
1.106 markus 1381:
1382: /* XXX should be pre-session */
1.368 djm 1383: if (!options.control_persist)
1384: ssh_init_stdio_forwarding();
1.106 markus 1385: ssh_init_forwarding();
1386:
1.344 djm 1387: /* Start listening for multiplex clients */
1388: muxserver_listen();
1389:
1390: /*
1.368 djm 1391: * If we are in control persist mode and have a working mux listen
1392: * socket, then prepare to background ourselves and have a foreground
1393: * client attach as a control slave.
1394: * NB. we must save copies of the flags that we override for
1.344 djm 1395: * the backgrounding, since we defer attachment of the slave until
1396: * after the connection is fully established (in particular,
1397: * async rfwd replies have been received for ExitOnForwardFailure).
1398: */
1399: if (options.control_persist && muxserver_sock != -1) {
1400: ostdin_null_flag = stdin_null_flag;
1401: ono_shell_flag = no_shell_flag;
1.359 djm 1402: orequest_tty = options.request_tty;
1.344 djm 1403: otty_flag = tty_flag;
1404: stdin_null_flag = 1;
1405: no_shell_flag = 1;
1406: tty_flag = 0;
1407: if (!fork_after_authentication_flag)
1408: need_controlpersist_detach = 1;
1409: fork_after_authentication_flag = 1;
1410: }
1.368 djm 1411: /*
1412: * ControlPersist mux listen socket setup failed, attempt the
1413: * stdio forward setup that we skipped earlier.
1414: */
1415: if (options.control_persist && muxserver_sock == -1)
1416: ssh_init_stdio_forwarding();
1.344 djm 1417:
1.143 markus 1418: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1419: id = ssh_session2_open();
1.379 djm 1420: else {
1421: packet_set_interactive(
1422: options.control_master == SSHCTL_MASTER_NO,
1423: options.ip_qos_interactive, options.ip_qos_bulk);
1424: }
1.314 djm 1425:
1426: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1427: if (options.control_master == SSHCTL_MASTER_NO &&
1428: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1429: debug("Requesting no-more-sessions@openssh.com");
1430: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1431: packet_put_cstring("no-more-sessions@openssh.com");
1432: packet_put_char(0);
1433: packet_send();
1434: }
1.255 reyk 1435:
1436: /* Execute a local command */
1437: if (options.local_command != NULL &&
1438: options.permit_local_command)
1439: ssh_local_cmd(options.local_command);
1.301 djm 1440:
1.342 djm 1441: /*
1442: * If requested and we are not interested in replies to remote
1443: * forwarding requests, then let ssh continue in the background.
1444: */
1.344 djm 1445: if (fork_after_authentication_flag) {
1446: if (options.exit_on_forward_failure &&
1447: options.num_remote_forwards > 0) {
1448: debug("deferring postauth fork until remote forward "
1449: "confirmation received");
1450: } else
1451: fork_postauth();
1.318 djm 1452: }
1.327 andreas 1453:
1454: if (options.use_roaming)
1455: request_roaming();
1.31 markus 1456:
1.119 stevesk 1457: return client_loop(tty_flag, tty_flag ?
1458: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1459: }
1460:
1.126 itojun 1461: static void
1.104 markus 1462: load_public_identity_files(void)
1463: {
1.275 djm 1464: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1465: char *pwdir = NULL, *pwname = NULL;
1.167 markus 1466: int i = 0;
1.104 markus 1467: Key *public;
1.275 djm 1468: struct passwd *pw;
1.335 djm 1469: u_int n_ids;
1470: char *identity_files[SSH_MAX_IDENTITY_FILES];
1471: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.333 markus 1472: #ifdef ENABLE_PKCS11
1.167 markus 1473: Key **keys;
1.333 markus 1474: int nkeys;
1.335 djm 1475: #endif /* PKCS11 */
1.104 markus 1476:
1.335 djm 1477: n_ids = 0;
1478: bzero(identity_files, sizeof(identity_files));
1479: bzero(identity_keys, sizeof(identity_keys));
1480:
1481: #ifdef ENABLE_PKCS11
1.333 markus 1482: if (options.pkcs11_provider != NULL &&
1.167 markus 1483: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1484: (pkcs11_init(!options.batch_mode) == 0) &&
1485: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1486: &keys)) > 0) {
1487: for (i = 0; i < nkeys; i++) {
1.335 djm 1488: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1489: key_free(keys[i]);
1490: continue;
1491: }
1492: identity_keys[n_ids] = keys[i];
1493: identity_files[n_ids] =
1.333 markus 1494: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 1495: n_ids++;
1.167 markus 1496: }
1.378 djm 1497: free(keys);
1.127 markus 1498: }
1.333 markus 1499: #endif /* ENABLE_PKCS11 */
1.275 djm 1500: if ((pw = getpwuid(original_real_uid)) == NULL)
1501: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 1502: pwname = xstrdup(pw->pw_name);
1503: pwdir = xstrdup(pw->pw_dir);
1.275 djm 1504: if (gethostname(thishost, sizeof(thishost)) == -1)
1505: fatal("load_public_identity_files: gethostname: %s",
1506: strerror(errno));
1.335 djm 1507: for (i = 0; i < options.num_identity_files; i++) {
1.373 djm 1508: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
1509: strcasecmp(options.identity_files[i], "none") == 0) {
1.378 djm 1510: free(options.identity_files[i]);
1.335 djm 1511: continue;
1512: }
1.275 djm 1513: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 1514: original_real_uid);
1.306 deraadt 1515: filename = percent_expand(cp, "d", pwdir,
1516: "u", pwname, "l", thishost, "h", host,
1.275 djm 1517: "r", options.user, (char *)NULL);
1.378 djm 1518: free(cp);
1.131 millert 1519: public = key_load_public(filename, NULL);
1520: debug("identity file %s type %d", filename,
1521: public ? public->type : -1);
1.378 djm 1522: free(options.identity_files[i]);
1.335 djm 1523: identity_files[n_ids] = filename;
1524: identity_keys[n_ids] = public;
1525:
1526: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
1527: continue;
1528:
1529: /* Try to add the certificate variant too */
1530: xasprintf(&cp, "%s-cert", filename);
1531: public = key_load_public(cp, NULL);
1532: debug("identity file %s type %d", cp,
1533: public ? public->type : -1);
1534: if (public == NULL) {
1.378 djm 1535: free(cp);
1.335 djm 1536: continue;
1537: }
1538: if (!key_is_cert(public)) {
1539: debug("%s: key %s type %s is not a certificate",
1540: __func__, cp, key_type(public));
1541: key_free(public);
1.378 djm 1542: free(cp);
1.335 djm 1543: continue;
1544: }
1545: identity_keys[n_ids] = public;
1546: /* point to the original path, most likely the private key */
1547: identity_files[n_ids] = xstrdup(filename);
1548: n_ids++;
1549: }
1550: options.num_identity_files = n_ids;
1551: memcpy(options.identity_files, identity_files, sizeof(identity_files));
1552: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1553:
1.306 deraadt 1554: bzero(pwname, strlen(pwname));
1.378 djm 1555: free(pwname);
1.306 deraadt 1556: bzero(pwdir, strlen(pwdir));
1.378 djm 1557: free(pwdir);
1.214 djm 1558: }
1.352 djm 1559:
1560: static void
1561: main_sigchld_handler(int sig)
1562: {
1563: int save_errno = errno;
1564: pid_t pid;
1565: int status;
1566:
1567: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
1568: (pid < 0 && errno == EINTR))
1569: ;
1570:
1571: signal(sig, main_sigchld_handler);
1572: errno = save_errno;
1573: }
1574:
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