Annotation of src/usr.bin/ssh/ssh.c, Revision 1.503
1.503 ! jmc 1: /* $OpenBSD: ssh.c,v 1.502 2019/06/06 05:13:13 otto 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>
45: #include <sys/queue.h>
1.259 stevesk 46: #include <sys/resource.h>
1.280 stevesk 47: #include <sys/socket.h>
1.264 stevesk 48: #include <sys/stat.h>
1.312 djm 49: #include <sys/time.h>
1.352 djm 50: #include <sys/wait.h>
1.258 stevesk 51:
1.265 stevesk 52: #include <ctype.h>
1.285 stevesk 53: #include <errno.h>
1.281 stevesk 54: #include <fcntl.h>
1.286 stevesk 55: #include <netdb.h>
1.258 stevesk 56: #include <paths.h>
1.279 stevesk 57: #include <pwd.h>
1.263 stevesk 58: #include <signal.h>
1.287 stevesk 59: #include <stddef.h>
1.291 stevesk 60: #include <stdio.h>
1.290 stevesk 61: #include <stdlib.h>
1.289 stevesk 62: #include <string.h>
1.288 stevesk 63: #include <unistd.h>
1.414 deraadt 64: #include <limits.h>
1.445 djm 65: #include <locale.h>
1.49 markus 66:
1.402 markus 67: #ifdef WITH_OPENSSL
1.49 markus 68: #include <openssl/evp.h>
1.72 markus 69: #include <openssl/err.h>
1.402 markus 70: #endif
1.1 deraadt 71:
1.293 deraadt 72: #include "xmalloc.h"
1.84 markus 73: #include "ssh.h"
74: #include "ssh2.h"
1.341 djm 75: #include "canohost.h"
1.84 markus 76: #include "compat.h"
77: #include "cipher.h"
1.405 djm 78: #include "digest.h"
1.1 deraadt 79: #include "packet.h"
1.482 markus 80: #include "sshbuf.h"
1.123 markus 81: #include "channels.h"
1.483 markus 82: #include "sshkey.h"
1.58 markus 83: #include "authfd.h"
1.49 markus 84: #include "authfile.h"
1.83 markus 85: #include "pathnames.h"
1.214 djm 86: #include "dispatch.h"
1.81 markus 87: #include "clientloop.h"
1.84 markus 88: #include "log.h"
1.406 millert 89: #include "misc.h"
1.84 markus 90: #include "readconf.h"
91: #include "sshconnect.h"
1.95 markus 92: #include "kex.h"
93: #include "mac.h"
1.213 deraadt 94: #include "sshpty.h"
1.212 djm 95: #include "match.h"
1.214 djm 96: #include "msg.h"
1.278 stevesk 97: #include "version.h"
1.412 djm 98: #include "ssherr.h"
1.420 djm 99: #include "myproposal.h"
1.49 markus 100:
1.333 markus 101: #ifdef ENABLE_PKCS11
102: #include "ssh-pkcs11.h"
1.137 jakob 103: #endif
1.498 djm 104:
1.49 markus 105: extern char *__progname;
1.1 deraadt 106:
1.316 djm 107: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 108: int debug_flag = 0;
109:
1.359 djm 110: /* Flag indicating whether a tty should be requested */
1.1 deraadt 111: int tty_flag = 0;
112:
1.45 markus 113: /* don't exec a shell */
114: int no_shell_flag = 0;
115:
1.33 markus 116: /*
117: * Flag indicating that nothing should be read from stdin. This can be set
118: * on the command line.
119: */
1.1 deraadt 120: int stdin_null_flag = 0;
121:
1.33 markus 122: /*
1.344 djm 123: * Flag indicating that the current process should be backgrounded and
124: * a new slave launched in the foreground for ControlPersist.
125: */
126: int need_controlpersist_detach = 0;
127:
128: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 129: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 130:
131: /*
1.33 markus 132: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 133: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 134: * background.
135: */
1.1 deraadt 136: int fork_after_authentication_flag = 0;
137:
1.33 markus 138: /*
139: * General data structure for command line options and options configurable
140: * in configuration files. See readconf.h.
141: */
1.1 deraadt 142: Options options;
143:
1.139 markus 144: /* optional user configfile */
145: char *config = NULL;
146:
1.33 markus 147: /*
148: * Name of the host we are connecting to. This is the name given on the
1.503 ! jmc 149: * command line, or the Hostname specified for the user-supplied name in a
1.33 markus 150: * configuration file.
151: */
1.1 deraadt 152: char *host;
153:
1.466 djm 154: /* Various strings used to to percent_expand() arguments */
155: static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
156: static char uidstr[32], *host_arg, *conn_hash_hex;
157:
1.22 provos 158: /* socket address the host resolves to */
1.37 markus 159: struct sockaddr_storage hostaddr;
1.1 deraadt 160:
1.112 markus 161: /* Private host keys. */
1.173 markus 162: Sensitive sensitive_data;
1.1 deraadt 163:
1.45 markus 164: /* command to be executed */
1.482 markus 165: struct sshbuf *command;
1.45 markus 166:
1.85 djm 167: /* Should we execute a command or invoke a subsystem? */
168: int subsystem_flag = 0;
169:
1.170 markus 170: /* # of replies received for global requests */
1.315 djm 171: static int remote_forward_confirms_received = 0;
1.170 markus 172:
1.313 djm 173: /* mux.c */
174: extern int muxserver_sock;
175: extern u_int muxclient_command;
176:
1.1 deraadt 177: /* Prints a help message to the user. This function never returns. */
178:
1.126 itojun 179: static void
1.93 itojun 180: usage(void)
1.1 deraadt 181: {
1.208 markus 182: fprintf(stderr,
1.474 djm 183: "usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n"
184: " [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n"
185: " [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n"
186: " [-i identity_file] [-J [user@]host[:port]] [-L address]\n"
187: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
188: " [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n"
189: " [-w local_tun[:remote_tun]] destination [command]\n"
1.208 markus 190: );
1.257 dtucker 191: exit(255);
1.1 deraadt 192: }
193:
1.466 djm 194: static int ssh_session2(struct ssh *, struct passwd *);
195: static void load_public_identity_files(struct passwd *);
1.352 djm 196: static void main_sigchld_handler(int);
1.312 djm 197:
1.361 djm 198: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
199: static void
200: tilde_expand_paths(char **paths, u_int num_paths)
201: {
202: u_int i;
203: char *cp;
204:
205: for (i = 0; i < num_paths; i++) {
1.490 dtucker 206: cp = tilde_expand_filename(paths[i], getuid());
1.378 djm 207: free(paths[i]);
1.361 djm 208: paths[i] = cp;
209: }
210: }
211:
1.400 djm 212: /*
213: * Attempt to resolve a host name / port to a set of addresses and
214: * optionally return any CNAMEs encountered along the way.
215: * Returns NULL on failure.
216: * NB. this function must operate with a options having undefined members.
217: */
1.385 djm 218: static struct addrinfo *
1.400 djm 219: resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
1.385 djm 220: {
221: char strport[NI_MAXSERV];
222: struct addrinfo hints, *res;
1.501 dtucker 223: int gaierr;
224: LogLevel loglevel = SYSLOG_LEVEL_DEBUG1;
1.385 djm 225:
1.400 djm 226: if (port <= 0)
227: port = default_ssh_port();
228:
1.427 djm 229: snprintf(strport, sizeof strport, "%d", port);
1.398 tedu 230: memset(&hints, 0, sizeof(hints));
1.400 djm 231: hints.ai_family = options.address_family == -1 ?
232: AF_UNSPEC : options.address_family;
1.385 djm 233: hints.ai_socktype = SOCK_STREAM;
234: if (cname != NULL)
235: hints.ai_flags = AI_CANONNAME;
236: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
237: if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
238: loglevel = SYSLOG_LEVEL_ERROR;
239: do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
240: __progname, name, ssh_gai_strerror(gaierr));
241: return NULL;
242: }
243: if (cname != NULL && res->ai_canonname != NULL) {
244: if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
245: error("%s: host \"%s\" cname \"%s\" too long (max %lu)",
246: __func__, name, res->ai_canonname, (u_long)clen);
247: if (clen > 0)
248: *cname = '\0';
249: }
250: }
251: return res;
252: }
253:
1.470 djm 254: /* Returns non-zero if name can only be an address and not a hostname */
255: static int
256: is_addr_fast(const char *name)
257: {
258: return (strchr(name, '%') != NULL || strchr(name, ':') != NULL ||
259: strspn(name, "0123456789.") == strlen(name));
260: }
261:
262: /* Returns non-zero if name represents a valid, single address */
263: static int
264: is_addr(const char *name)
265: {
266: char strport[NI_MAXSERV];
267: struct addrinfo hints, *res;
268:
269: if (is_addr_fast(name))
270: return 1;
271:
272: snprintf(strport, sizeof strport, "%u", default_ssh_port());
273: memset(&hints, 0, sizeof(hints));
274: hints.ai_family = options.address_family == -1 ?
275: AF_UNSPEC : options.address_family;
276: hints.ai_socktype = SOCK_STREAM;
277: hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
278: if (getaddrinfo(name, strport, &hints, &res) != 0)
279: return 0;
280: if (res == NULL || res->ai_next != NULL) {
281: freeaddrinfo(res);
282: return 0;
283: }
284: freeaddrinfo(res);
285: return 1;
286: }
287:
1.385 djm 288: /*
1.413 djm 289: * Attempt to resolve a numeric host address / port to a single address.
290: * Returns a canonical address string.
291: * Returns NULL on failure.
292: * NB. this function must operate with a options having undefined members.
293: */
294: static struct addrinfo *
295: resolve_addr(const char *name, int port, char *caddr, size_t clen)
296: {
297: char addr[NI_MAXHOST], strport[NI_MAXSERV];
298: struct addrinfo hints, *res;
299: int gaierr;
300:
301: if (port <= 0)
302: port = default_ssh_port();
303: snprintf(strport, sizeof strport, "%u", port);
304: memset(&hints, 0, sizeof(hints));
305: hints.ai_family = options.address_family == -1 ?
306: AF_UNSPEC : options.address_family;
307: hints.ai_socktype = SOCK_STREAM;
308: hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
309: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
310: debug2("%s: could not resolve name %.100s as address: %s",
311: __func__, name, ssh_gai_strerror(gaierr));
312: return NULL;
313: }
314: if (res == NULL) {
315: debug("%s: getaddrinfo %.100s returned no addresses",
316: __func__, name);
317: return NULL;
318: }
319: if (res->ai_next != NULL) {
320: debug("%s: getaddrinfo %.100s returned multiple addresses",
321: __func__, name);
322: goto fail;
323: }
324: if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
325: addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
326: debug("%s: Could not format address for name %.100s: %s",
327: __func__, name, ssh_gai_strerror(gaierr));
328: goto fail;
329: }
330: if (strlcpy(caddr, addr, clen) >= clen) {
331: error("%s: host \"%s\" addr \"%s\" too long (max %lu)",
332: __func__, name, addr, (u_long)clen);
333: if (clen > 0)
334: *caddr = '\0';
335: fail:
336: freeaddrinfo(res);
337: return NULL;
338: }
339: return res;
340: }
341:
342: /*
1.385 djm 343: * Check whether the cname is a permitted replacement for the hostname
344: * and perform the replacement if it is.
1.400 djm 345: * NB. this function must operate with a options having undefined members.
1.385 djm 346: */
347: static int
1.443 djm 348: check_follow_cname(int direct, char **namep, const char *cname)
1.385 djm 349: {
350: int i;
351: struct allowed_cname *rule;
352:
353: if (*cname == '\0' || options.num_permitted_cnames == 0 ||
354: strcmp(*namep, cname) == 0)
355: return 0;
1.386 djm 356: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
1.385 djm 357: return 0;
358: /*
1.386 djm 359: * Don't attempt to canonicalize names that will be interpreted by
1.443 djm 360: * a proxy or jump host unless the user specifically requests so.
1.385 djm 361: */
1.443 djm 362: if (!direct &&
1.386 djm 363: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
1.385 djm 364: return 0;
365: debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname);
366: for (i = 0; i < options.num_permitted_cnames; i++) {
367: rule = options.permitted_cnames + i;
1.418 djm 368: if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
369: match_pattern_list(cname, rule->target_list, 1) != 1)
1.385 djm 370: continue;
1.386 djm 371: verbose("Canonicalized DNS aliased hostname "
1.385 djm 372: "\"%s\" => \"%s\"", *namep, cname);
373: free(*namep);
374: *namep = xstrdup(cname);
375: return 1;
376: }
377: return 0;
378: }
379:
380: /*
381: * Attempt to resolve the supplied hostname after applying the user's
1.387 djm 382: * canonicalization rules. Returns the address list for the host or NULL
383: * if no name was found after canonicalization.
1.400 djm 384: * NB. this function must operate with a options having undefined members.
1.385 djm 385: */
386: static struct addrinfo *
1.400 djm 387: resolve_canonicalize(char **hostp, int port)
1.385 djm 388: {
1.443 djm 389: int i, direct, ndots;
1.413 djm 390: char *cp, *fullhost, newname[NI_MAXHOST];
1.385 djm 391: struct addrinfo *addrs;
392:
393: /*
1.470 djm 394: * Attempt to canonicalise addresses, regardless of
395: * whether hostname canonicalisation was requested
1.385 djm 396: */
1.413 djm 397: if ((addrs = resolve_addr(*hostp, port,
398: newname, sizeof(newname))) != NULL) {
399: debug2("%s: hostname %.100s is address", __func__, *hostp);
400: if (strcasecmp(*hostp, newname) != 0) {
401: debug2("%s: canonicalised address \"%s\" => \"%s\"",
402: __func__, *hostp, newname);
403: free(*hostp);
404: *hostp = xstrdup(newname);
405: }
406: return addrs;
407: }
408:
1.470 djm 409: /*
410: * If this looks like an address but didn't parse as one, it might
411: * be an address with an invalid interface scope. Skip further
412: * attempts at canonicalisation.
413: */
414: if (is_addr_fast(*hostp)) {
415: debug("%s: hostname %.100s is an unrecognised address",
416: __func__, *hostp);
417: return NULL;
418: }
419:
420: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
421: return NULL;
422:
423: /*
424: * Don't attempt to canonicalize names that will be interpreted by
425: * a proxy unless the user specifically requests so.
426: */
427: direct = option_clear_or_none(options.proxy_command) &&
428: options.jump_host == NULL;
429: if (!direct &&
430: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
431: return NULL;
432:
1.428 djm 433: /* If domain name is anchored, then resolve it now */
434: if ((*hostp)[strlen(*hostp) - 1] == '.') {
435: debug3("%s: name is fully qualified", __func__);
436: fullhost = xstrdup(*hostp);
437: if ((addrs = resolve_host(fullhost, port, 0,
438: newname, sizeof(newname))) != NULL)
439: goto found;
440: free(fullhost);
441: goto notfound;
442: }
443:
1.387 djm 444: /* Don't apply canonicalization to sufficiently-qualified hostnames */
1.385 djm 445: ndots = 0;
446: for (cp = *hostp; *cp != '\0'; cp++) {
447: if (*cp == '.')
448: ndots++;
449: }
1.386 djm 450: if (ndots > options.canonicalize_max_dots) {
451: debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)",
452: __func__, *hostp, options.canonicalize_max_dots);
1.385 djm 453: return NULL;
454: }
455: /* Attempt each supplied suffix */
456: for (i = 0; i < options.num_canonical_domains; i++) {
1.413 djm 457: *newname = '\0';
1.385 djm 458: xasprintf(&fullhost, "%s.%s.", *hostp,
459: options.canonical_domains[i]);
1.400 djm 460: debug3("%s: attempting \"%s\" => \"%s\"", __func__,
461: *hostp, fullhost);
462: if ((addrs = resolve_host(fullhost, port, 0,
1.413 djm 463: newname, sizeof(newname))) == NULL) {
1.385 djm 464: free(fullhost);
465: continue;
466: }
1.428 djm 467: found:
1.385 djm 468: /* Remove trailing '.' */
469: fullhost[strlen(fullhost) - 1] = '\0';
470: /* Follow CNAME if requested */
1.443 djm 471: if (!check_follow_cname(direct, &fullhost, newname)) {
1.386 djm 472: debug("Canonicalized hostname \"%s\" => \"%s\"",
1.385 djm 473: *hostp, fullhost);
474: }
475: free(*hostp);
476: *hostp = fullhost;
477: return addrs;
478: }
1.428 djm 479: notfound:
1.386 djm 480: if (!options.canonicalize_fallback_local)
1.400 djm 481: fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
482: debug2("%s: host %s not found in any suffix", __func__, *hostp);
1.385 djm 483: return NULL;
484: }
485:
1.32 deraadt 486: /*
1.483 markus 487: * Check the result of hostkey loading, ignoring some errors and
488: * fatal()ing for others.
489: */
490: static void
491: check_load(int r, const char *path, const char *message)
492: {
493: switch (r) {
494: case 0:
495: break;
496: case SSH_ERR_INTERNAL_ERROR:
497: case SSH_ERR_ALLOC_FAIL:
498: fatal("load %s \"%s\": %s", message, path, ssh_err(r));
499: case SSH_ERR_SYSTEM_ERROR:
500: /* Ignore missing files */
501: if (errno == ENOENT)
502: break;
503: /* FALLTHROUGH */
504: default:
505: error("load %s \"%s\": %s", message, path, ssh_err(r));
506: break;
507: }
508: }
509:
510: /*
1.400 djm 511: * Read per-user configuration file. Ignore the system wide config
512: * file if the user specifies a config file on the command line.
513: */
514: static void
1.496 djm 515: process_config_files(const char *host_name, struct passwd *pw, int final_pass,
516: int *want_final_pass)
1.400 djm 517: {
1.414 deraadt 518: char buf[PATH_MAX];
1.400 djm 519: int r;
520:
521: if (config != NULL) {
522: if (strcasecmp(config, "none") != 0 &&
1.466 djm 523: !read_config_file(config, pw, host, host_name, &options,
1.496 djm 524: SSHCONF_USERCONF | (final_pass ? SSHCONF_FINAL : 0),
525: want_final_pass))
1.400 djm 526: fatal("Can't open user config file %.100s: "
527: "%.100s", config, strerror(errno));
528: } else {
529: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
530: _PATH_SSH_USER_CONFFILE);
531: if (r > 0 && (size_t)r < sizeof(buf))
1.466 djm 532: (void)read_config_file(buf, pw, host, host_name,
1.408 djm 533: &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
1.496 djm 534: (final_pass ? SSHCONF_FINAL : 0), want_final_pass);
1.400 djm 535:
536: /* Read systemwide configuration file after user config. */
1.408 djm 537: (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
1.466 djm 538: host, host_name, &options,
1.496 djm 539: final_pass ? SSHCONF_FINAL : 0, want_final_pass);
1.408 djm 540: }
541: }
542:
543: /* Rewrite the port number in an addrinfo list of addresses */
544: static void
545: set_addrinfo_port(struct addrinfo *addrs, int port)
546: {
547: struct addrinfo *addr;
548:
549: for (addr = addrs; addr != NULL; addr = addr->ai_next) {
550: switch (addr->ai_family) {
551: case AF_INET:
552: ((struct sockaddr_in *)addr->ai_addr)->
553: sin_port = htons(port);
554: break;
555: case AF_INET6:
556: ((struct sockaddr_in6 *)addr->ai_addr)->
557: sin6_port = htons(port);
558: break;
559: }
1.400 djm 560: }
561: }
562:
563: /*
1.32 deraadt 564: * Main program for the ssh client.
565: */
1.2 provos 566: int
567: main(int ac, char **av)
1.1 deraadt 568: {
1.437 djm 569: struct ssh *ssh = NULL;
1.462 djm 570: int i, r, opt, exit_status, use_syslog, direct, timeout_ms;
1.496 djm 571: int was_addr, config_test = 0, opt_terminated = 0, want_final_pass = 0;
1.466 djm 572: char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile;
573: char cname[NI_MAXHOST];
1.31 markus 574: struct stat st;
1.98 markus 575: struct passwd *pw;
1.144 stevesk 576: extern int optind, optreset;
577: extern char *optarg;
1.406 millert 578: struct Forward fwd;
1.385 djm 579: struct addrinfo *addrs = NULL;
1.405 djm 580: struct ssh_digest_ctx *md;
581: u_char conn_hash[SSH_DIGEST_MAX_LENGTH];
1.250 djm 582:
583: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
584: sanitise_stdfd();
1.31 markus 585:
1.33 markus 586: /*
1.346 djm 587: * Discard other fds that are hanging around. These can cause problem
588: * with backgrounded ssh processes started by ControlPersist.
589: */
590: closefrom(STDERR_FILENO + 1);
591:
1.487 dtucker 592: if (getuid() != geteuid())
593: fatal("ssh setuid not supported.");
594: if (getgid() != getegid())
595: fatal("ssh setgid not supported.");
1.184 stevesk 596:
1.107 markus 597: /* Get user data. */
1.490 dtucker 598: pw = getpwuid(getuid());
1.107 markus 599: if (!pw) {
1.490 dtucker 600: logit("No user exists for uid %lu", (u_long)getuid());
1.257 dtucker 601: exit(255);
1.107 markus 602: }
603: /* Take a copy of the returned structure. */
604: pw = pwcopy(pw);
1.31 markus 605:
1.33 markus 606: /*
607: * Set our umask to something reasonable, as some files are created
608: * with the default umask. This will make them world-readable but
609: * writable only by the owner, which is ok for all files for which we
610: * don't set the modes explicitly.
611: */
1.31 markus 612: umask(022);
1.445 djm 613:
614: setlocale(LC_CTYPE, "");
1.31 markus 615:
1.316 djm 616: /*
617: * Initialize option structure to indicate that no values have been
618: * set.
619: */
1.31 markus 620: initialize_options(&options);
621:
1.463 djm 622: /*
623: * Prepare main ssh transport/connection structures
624: */
625: if ((ssh = ssh_alloc_session_state()) == NULL)
626: fatal("Couldn't allocate session state");
627: channel_init_channels(ssh);
628:
1.31 markus 629: /* Parse command-line arguments. */
630: host = NULL;
1.320 djm 631: use_syslog = 0;
1.375 dtucker 632: logfile = NULL;
1.325 markus 633: argv0 = av[0];
1.31 markus 634:
1.266 djm 635: again:
1.316 djm 636: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.474 djm 637: "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
1.31 markus 638: switch (opt) {
1.91 jakob 639: case '1':
1.454 djm 640: fatal("SSH protocol v.1 is no longer supported");
1.91 jakob 641: break;
1.47 markus 642: case '2':
1.454 djm 643: /* Ignored */
1.47 markus 644: break;
1.37 markus 645: case '4':
1.196 djm 646: options.address_family = AF_INET;
1.37 markus 647: break;
648: case '6':
1.196 djm 649: options.address_family = AF_INET6;
1.37 markus 650: break;
1.31 markus 651: case 'n':
652: stdin_null_flag = 1;
653: break;
654: case 'f':
655: fork_after_authentication_flag = 1;
656: stdin_null_flag = 1;
657: break;
658: case 'x':
659: options.forward_x11 = 0;
660: break;
661: case 'X':
662: options.forward_x11 = 1;
663: break;
1.320 djm 664: case 'y':
665: use_syslog = 1;
666: break;
1.375 dtucker 667: case 'E':
1.422 dtucker 668: logfile = optarg;
1.375 dtucker 669: break;
1.408 djm 670: case 'G':
671: config_test = 1;
672: break;
1.202 markus 673: case 'Y':
674: options.forward_x11 = 1;
675: options.forward_x11_trusted = 1;
676: break;
1.31 markus 677: case 'g':
1.406 millert 678: options.fwd_opts.gateway_ports = 1;
1.31 markus 679: break;
1.229 djm 680: case 'O':
1.441 dtucker 681: if (options.stdio_forward_host != NULL)
1.332 djm 682: fatal("Cannot specify multiplexing "
683: "command with -W");
684: else if (muxclient_command != 0)
685: fatal("Multiplexing command already specified");
1.229 djm 686: if (strcmp(optarg, "check") == 0)
1.312 djm 687: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 688: else if (strcmp(optarg, "forward") == 0)
689: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 690: else if (strcmp(optarg, "exit") == 0)
1.312 djm 691: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 692: else if (strcmp(optarg, "stop") == 0)
693: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 694: else if (strcmp(optarg, "cancel") == 0)
695: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.447 markus 696: else if (strcmp(optarg, "proxy") == 0)
697: muxclient_command = SSHMUX_COMMAND_PROXY;
1.229 djm 698: else
699: fatal("Invalid multiplex command.");
700: break;
1.183 stevesk 701: case 'P': /* deprecated */
1.376 djm 702: break;
1.394 deraadt 703: case 'Q':
1.376 djm 704: cp = NULL;
1.394 deraadt 705: if (strcmp(optarg, "cipher") == 0)
1.393 djm 706: cp = cipher_alg_list('\n', 0);
1.394 deraadt 707: else if (strcmp(optarg, "cipher-auth") == 0)
1.393 djm 708: cp = cipher_alg_list('\n', 1);
1.394 deraadt 709: else if (strcmp(optarg, "mac") == 0)
1.392 dtucker 710: cp = mac_alg_list('\n');
1.394 deraadt 711: else if (strcmp(optarg, "kex") == 0)
1.392 dtucker 712: cp = kex_alg_list('\n');
1.394 deraadt 713: else if (strcmp(optarg, "key") == 0)
1.451 djm 714: cp = sshkey_alg_list(0, 0, 0, '\n');
1.396 markus 715: else if (strcmp(optarg, "key-cert") == 0)
1.451 djm 716: cp = sshkey_alg_list(1, 0, 0, '\n');
1.396 markus 717: else if (strcmp(optarg, "key-plain") == 0)
1.451 djm 718: cp = sshkey_alg_list(0, 1, 0, '\n');
1.491 djm 719: else if (strcmp(optarg, "sig") == 0)
1.492 djm 720: cp = sshkey_alg_list(0, 1, 1, '\n');
1.491 djm 721: else if (strcmp(optarg, "protocol-version") == 0)
1.416 djm 722: cp = xstrdup("2");
1.491 djm 723: else if (strcmp(optarg, "help") == 0) {
724: cp = xstrdup(
725: "cipher\ncipher-auth\nkex\nkey\n"
726: "key-cert\nkey-plain\nmac\n"
727: "protocol-version\nsig");
1.416 djm 728: }
1.376 djm 729: if (cp == NULL)
730: fatal("Unsupported query \"%s\"", optarg);
731: printf("%s\n", cp);
732: free(cp);
733: exit(0);
1.31 markus 734: break;
735: case 'a':
736: options.forward_agent = 0;
1.53 markus 737: break;
738: case 'A':
739: options.forward_agent = 1;
1.31 markus 740: break;
741: case 'k':
1.204 dtucker 742: options.gss_deleg_creds = 0;
1.297 djm 743: break;
744: case 'K':
745: options.gss_authentication = 1;
746: options.gss_deleg_creds = 1;
1.31 markus 747: break;
748: case 'i':
1.490 dtucker 749: p = tilde_expand_filename(optarg, getuid());
1.429 dtucker 750: if (stat(p, &st) < 0)
1.128 fgsch 751: fprintf(stderr, "Warning: Identity file %s "
1.429 dtucker 752: "not accessible: %s.\n", p,
1.231 otto 753: strerror(errno));
1.429 dtucker 754: else
755: add_identity_file(&options, NULL, p, 1);
756: free(p);
1.31 markus 757: break;
1.127 markus 758: case 'I':
1.333 markus 759: #ifdef ENABLE_PKCS11
1.422 dtucker 760: free(options.pkcs11_provider);
1.333 markus 761: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 762: #else
1.333 markus 763: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 764: #endif
1.127 markus 765: break;
1.443 djm 766: case 'J':
767: if (options.jump_host != NULL)
768: fatal("Only a single -J option permitted");
769: if (options.proxy_command != NULL)
770: fatal("Cannot specify -J with ProxyCommand");
771: if (parse_jump(optarg, &options, 1) == -1)
772: fatal("Invalid -J argument");
773: options.proxy_command = xstrdup("none");
774: break;
1.31 markus 775: case 't':
1.359 djm 776: if (options.request_tty == REQUEST_TTY_YES)
777: options.request_tty = REQUEST_TTY_FORCE;
778: else
779: options.request_tty = REQUEST_TTY_YES;
1.31 markus 780: break;
781: case 'v':
1.197 markus 782: if (debug_flag == 0) {
1.66 markus 783: debug_flag = 1;
784: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 785: } else {
1.443 djm 786: if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
787: debug_flag++;
1.197 markus 788: options.log_level++;
1.443 djm 789: }
1.197 markus 790: }
1.375 dtucker 791: break;
1.31 markus 792: case 'V':
1.209 markus 793: fprintf(stderr, "%s, %s\n",
1.402 markus 794: SSH_VERSION,
795: #ifdef WITH_OPENSSL
1.495 djm 796: OpenSSL_version(OPENSSL_VERSION)
1.402 markus 797: #else
798: "without OpenSSL"
799: #endif
800: );
1.31 markus 801: if (opt == 'V')
802: exit(0);
803: break;
1.255 reyk 804: case 'w':
1.256 reyk 805: if (options.tun_open == -1)
806: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 807: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 808: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 809: fprintf(stderr,
810: "Bad tun device '%s'\n", optarg);
1.257 dtucker 811: exit(255);
1.255 reyk 812: }
813: break;
1.331 dtucker 814: case 'W':
1.441 dtucker 815: if (options.stdio_forward_host != NULL)
1.332 djm 816: fatal("stdio forward already specified");
817: if (muxclient_command != 0)
818: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 819: if (parse_forward(&fwd, optarg, 1, 0)) {
1.441 dtucker 820: options.stdio_forward_host = fwd.listen_host;
821: options.stdio_forward_port = fwd.listen_port;
1.378 djm 822: free(fwd.connect_host);
1.331 dtucker 823: } else {
824: fprintf(stderr,
825: "Bad stdio forwarding specification '%s'\n",
826: optarg);
827: exit(255);
828: }
1.359 djm 829: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 830: no_shell_flag = 1;
831: break;
1.31 markus 832: case 'q':
833: options.log_level = SYSLOG_LEVEL_QUIET;
834: break;
835: case 'e':
836: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 837: (u_char) optarg[1] >= 64 &&
838: (u_char) optarg[1] < 128)
1.78 markus 839: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 840: else if (strlen(optarg) == 1)
1.78 markus 841: options.escape_char = (u_char) optarg[0];
1.31 markus 842: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 843: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 844: else {
1.128 fgsch 845: fprintf(stderr, "Bad escape character '%s'.\n",
846: optarg);
1.257 dtucker 847: exit(255);
1.31 markus 848: }
849: break;
850: case 'c':
1.456 djm 851: if (!ciphers_valid(*optarg == '+' ?
1.420 djm 852: optarg + 1 : optarg)) {
853: fprintf(stderr, "Unknown cipher type '%s'\n",
854: optarg);
855: exit(255);
1.95 markus 856: }
1.456 djm 857: free(options.ciphers);
858: options.ciphers = xstrdup(optarg);
1.95 markus 859: break;
860: case 'm':
1.422 dtucker 861: if (mac_valid(optarg)) {
862: free(options.macs);
1.95 markus 863: options.macs = xstrdup(optarg);
1.422 dtucker 864: } else {
1.128 fgsch 865: fprintf(stderr, "Unknown mac type '%s'\n",
866: optarg);
1.257 dtucker 867: exit(255);
1.31 markus 868: }
869: break;
1.214 djm 870: case 'M':
1.242 djm 871: if (options.control_master == SSHCTL_MASTER_YES)
872: options.control_master = SSHCTL_MASTER_ASK;
873: else
874: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 875: break;
1.31 markus 876: case 'p':
1.465 millert 877: if (options.port == -1) {
878: options.port = a2port(optarg);
879: if (options.port <= 0) {
880: fprintf(stderr, "Bad port '%s'\n",
881: optarg);
882: exit(255);
883: }
1.109 markus 884: }
1.31 markus 885: break;
886: case 'l':
1.465 millert 887: if (options.user == NULL)
888: options.user = optarg;
1.31 markus 889: break;
1.141 stevesk 890:
891: case 'L':
1.324 djm 892: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 893: add_local_forward(&options, &fwd);
894: else {
1.128 fgsch 895: fprintf(stderr,
1.232 djm 896: "Bad local forwarding specification '%s'\n",
1.128 fgsch 897: optarg);
1.257 dtucker 898: exit(255);
1.31 markus 899: }
1.232 djm 900: break;
901:
902: case 'R':
1.464 markus 903: if (parse_forward(&fwd, optarg, 0, 1) ||
904: parse_forward(&fwd, optarg, 1, 1)) {
1.232 djm 905: add_remote_forward(&options, &fwd);
906: } else {
1.128 fgsch 907: fprintf(stderr,
1.232 djm 908: "Bad remote forwarding specification "
909: "'%s'\n", optarg);
1.257 dtucker 910: exit(255);
1.31 markus 911: }
912: break;
1.108 markus 913:
914: case 'D':
1.324 djm 915: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 916: add_local_forward(&options, &fwd);
1.232 djm 917: } else {
1.322 stevesk 918: fprintf(stderr,
919: "Bad dynamic forwarding specification "
920: "'%s'\n", optarg);
1.257 dtucker 921: exit(255);
1.109 markus 922: }
1.108 markus 923: break;
924:
1.31 markus 925: case 'C':
926: options.compression = 1;
927: break;
1.45 markus 928: case 'N':
929: no_shell_flag = 1;
1.359 djm 930: options.request_tty = REQUEST_TTY_NO;
1.45 markus 931: break;
932: case 'T':
1.359 djm 933: options.request_tty = REQUEST_TTY_NO;
1.45 markus 934: break;
1.31 markus 935: case 'o':
1.205 markus 936: line = xstrdup(optarg);
1.408 djm 937: if (process_config_line(&options, pw,
938: host ? host : "", host ? host : "", line,
939: "command-line", 0, NULL, SSHCONF_USERCONF) != 0)
1.257 dtucker 940: exit(255);
1.378 djm 941: free(line);
1.31 markus 942: break;
1.85 djm 943: case 's':
944: subsystem_flag = 1;
1.117 markus 945: break;
1.214 djm 946: case 'S':
1.431 mmcc 947: free(options.control_path);
1.214 djm 948: options.control_path = xstrdup(optarg);
949: break;
1.117 markus 950: case 'b':
951: options.bind_address = optarg;
1.474 djm 952: break;
953: case 'B':
954: options.bind_interface = optarg;
1.85 djm 955: break;
1.139 markus 956: case 'F':
957: config = optarg;
958: break;
1.31 markus 959: default:
960: usage();
1.1 deraadt 961: }
1.31 markus 962: }
963:
1.462 djm 964: if (optind > 1 && strcmp(av[optind - 1], "--") == 0)
965: opt_terminated = 1;
966:
1.128 fgsch 967: ac -= optind;
968: av += optind;
969:
1.329 guenther 970: if (ac > 0 && !host) {
1.465 millert 971: int tport;
972: char *tuser;
973: switch (parse_ssh_uri(*av, &tuser, &host, &tport)) {
974: case -1:
975: usage();
976: break;
977: case 0:
978: if (options.user == NULL) {
979: options.user = tuser;
980: tuser = NULL;
981: }
982: free(tuser);
983: if (options.port == -1 && tport != -1)
984: options.port = tport;
985: break;
986: default:
1.128 fgsch 987: p = xstrdup(*av);
1.188 markus 988: cp = strrchr(p, '@');
1.465 millert 989: if (cp != NULL) {
990: if (cp == p)
991: usage();
992: if (options.user == NULL) {
993: options.user = p;
994: p = NULL;
995: }
996: *cp++ = '\0';
997: host = xstrdup(cp);
998: free(p);
999: } else
1000: host = p;
1001: break;
1002: }
1.462 djm 1003: if (ac > 1 && !opt_terminated) {
1.189 millert 1004: optind = optreset = 1;
1.128 fgsch 1005: goto again;
1006: }
1.189 millert 1007: ac--, av++;
1.128 fgsch 1008: }
1009:
1.31 markus 1010: /* Check that we got a host name. */
1011: if (!host)
1012: usage();
1013:
1.385 djm 1014: host_arg = xstrdup(host);
1015:
1.402 markus 1016: #ifdef WITH_OPENSSL
1.350 djm 1017: OpenSSL_add_all_algorithms();
1.72 markus 1018: ERR_load_crypto_strings();
1.402 markus 1019: #endif
1.31 markus 1020:
1021: /* Initialize the command to execute on remote host. */
1.482 markus 1022: if ((command = sshbuf_new()) == NULL)
1023: fatal("sshbuf_new failed");
1.1 deraadt 1024:
1.33 markus 1025: /*
1026: * Save the command to execute on the remote host in a buffer. There
1027: * is no limit on the length of the command, except by the maximum
1028: * packet size. Also sets the tty flag if there is no command.
1029: */
1.128 fgsch 1030: if (!ac) {
1.31 markus 1031: /* No command specified - execute shell on a tty. */
1.85 djm 1032: if (subsystem_flag) {
1.128 fgsch 1033: fprintf(stderr,
1034: "You must specify a subsystem to invoke.\n");
1.85 djm 1035: usage();
1036: }
1.31 markus 1037: } else {
1.128 fgsch 1038: /* A command has been specified. Store it into the buffer. */
1039: for (i = 0; i < ac; i++) {
1.482 markus 1040: if ((r = sshbuf_putf(command, "%s%s",
1041: i ? " " : "", av[i])) != 0)
1042: fatal("%s: buffer error: %s",
1043: __func__, ssh_err(r));
1.31 markus 1044: }
1045: }
1046:
1.101 markus 1047: /*
1048: * Initialize "log" output. Since we are the client all output
1.375 dtucker 1049: * goes to stderr unless otherwise specified by -y or -E.
1.101 markus 1050: */
1.375 dtucker 1051: if (use_syslog && logfile != NULL)
1052: fatal("Can't specify both -y and -E");
1.422 dtucker 1053: if (logfile != NULL)
1.375 dtucker 1054: log_redirect_stderr_to(logfile);
1.325 markus 1055: log_init(argv0,
1.468 djm 1056: options.log_level == SYSLOG_LEVEL_NOT_SET ?
1.452 dtucker 1057: SYSLOG_LEVEL_INFO : options.log_level,
1.468 djm 1058: options.log_facility == SYSLOG_FACILITY_NOT_SET ?
1.452 dtucker 1059: SYSLOG_FACILITY_USER : options.log_facility,
1060: !use_syslog);
1.375 dtucker 1061:
1062: if (debug_flag)
1.402 markus 1063: logit("%s, %s", SSH_VERSION,
1064: #ifdef WITH_OPENSSL
1.495 djm 1065: OpenSSL_version(OPENSSL_VERSION)
1.402 markus 1066: #else
1067: "without OpenSSL"
1068: #endif
1069: );
1.31 markus 1070:
1.400 djm 1071: /* Parse the configuration files */
1.496 djm 1072: process_config_files(host_arg, pw, 0, &want_final_pass);
1073: if (want_final_pass)
1074: debug("configuration requests final Match pass");
1.400 djm 1075:
1076: /* Hostname canonicalisation needs a few options filled. */
1077: fill_default_options_for_canonicalization(&options);
1078:
1079: /* If the user has replaced the hostname then take it into use now */
1080: if (options.hostname != NULL) {
1081: /* NB. Please keep in sync with readconf.c:match_cfg_line() */
1082: cp = percent_expand(options.hostname,
1083: "h", host, (char *)NULL);
1084: free(host);
1085: host = cp;
1.408 djm 1086: free(options.hostname);
1087: options.hostname = xstrdup(host);
1.400 djm 1088: }
1089:
1.470 djm 1090: /* Don't lowercase addresses, they will be explicitly canonicalised */
1091: if ((was_addr = is_addr(host)) == 0)
1092: lowercase(host);
1093:
1094: /*
1095: * Try to canonicalize if requested by configuration or the
1096: * hostname is an address.
1097: */
1098: if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr)
1.400 djm 1099: addrs = resolve_canonicalize(&host, options.port);
1100:
1.139 markus 1101: /*
1.401 djm 1102: * If CanonicalizePermittedCNAMEs have been specified but
1103: * other canonicalization did not happen (by not being requested
1104: * or by failing with fallback) then the hostname may still be changed
1.468 djm 1105: * as a result of CNAME following.
1.401 djm 1106: *
1107: * Try to resolve the bare hostname name using the system resolver's
1108: * usual search rules and then apply the CNAME follow rules.
1109: *
1110: * Skip the lookup if a ProxyCommand is being used unless the user
1111: * has specifically requested canonicalisation for this case via
1112: * CanonicalizeHostname=always
1.139 markus 1113: */
1.443 djm 1114: direct = option_clear_or_none(options.proxy_command) &&
1115: options.jump_host == NULL;
1116: if (addrs == NULL && options.num_permitted_cnames != 0 && (direct ||
1117: options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
1.403 djm 1118: if ((addrs = resolve_host(host, options.port,
1.493 djm 1119: direct, cname, sizeof(cname))) == NULL) {
1.403 djm 1120: /* Don't fatal proxied host names not in the DNS */
1.493 djm 1121: if (direct)
1.403 djm 1122: cleanup_exit(255); /* logged in resolve_host */
1123: } else
1.443 djm 1124: check_follow_cname(direct, &host, cname);
1.400 djm 1125: }
1.139 markus 1126:
1.400 djm 1127: /*
1.408 djm 1128: * If canonicalisation is enabled then re-parse the configuration
1129: * files as new stanzas may match.
1.400 djm 1130: */
1.496 djm 1131: if (options.canonicalize_hostname != 0 && !want_final_pass) {
1132: debug("hostname canonicalisation enabled, "
1133: "will re-parse configuration");
1134: want_final_pass = 1;
1135: }
1136:
1137: if (want_final_pass) {
1138: debug("re-parsing configuration");
1.408 djm 1139: free(options.hostname);
1140: options.hostname = xstrdup(host);
1.496 djm 1141: process_config_files(host_arg, pw, 1, NULL);
1.408 djm 1142: /*
1143: * Address resolution happens early with canonicalisation
1144: * enabled and the port number may have changed since, so
1145: * reset it in address list
1146: */
1147: if (addrs != NULL && options.port > 0)
1148: set_addrinfo_port(addrs, options.port);
1.139 markus 1149: }
1.31 markus 1150:
1151: /* Fill configuration defaults. */
1152: fill_default_options(&options);
1.443 djm 1153:
1154: /*
1155: * If ProxyJump option specified, then construct a ProxyCommand now.
1156: */
1157: if (options.jump_host != NULL) {
1158: char port_s[8];
1.478 djm 1159: const char *sshbin = argv0;
1160:
1161: /*
1162: * Try to use SSH indicated by argv[0], but fall back to
1163: * "ssh" if it appears unavailable.
1164: */
1165: if (strchr(argv0, '/') != NULL && access(argv0, X_OK) != 0)
1166: sshbin = "ssh";
1.443 djm 1167:
1168: /* Consistency check */
1169: if (options.proxy_command != NULL)
1170: fatal("inconsistent options: ProxyCommand+ProxyJump");
1171: /* Never use FD passing for ProxyJump */
1172: options.proxy_use_fdpass = 0;
1173: snprintf(port_s, sizeof(port_s), "%d", options.jump_port);
1174: xasprintf(&options.proxy_command,
1.478 djm 1175: "%s%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s",
1176: sshbin,
1.443 djm 1177: /* Optional "-l user" argument if jump_user set */
1178: options.jump_user == NULL ? "" : " -l ",
1179: options.jump_user == NULL ? "" : options.jump_user,
1180: /* Optional "-p port" argument if jump_port set */
1181: options.jump_port <= 0 ? "" : " -p ",
1182: options.jump_port <= 0 ? "" : port_s,
1183: /* Optional additional jump hosts ",..." */
1184: options.jump_extra == NULL ? "" : " -J ",
1185: options.jump_extra == NULL ? "" : options.jump_extra,
1186: /* Optional "-F" argumment if -F specified */
1187: config == NULL ? "" : " -F ",
1188: config == NULL ? "" : config,
1189: /* Optional "-v" arguments if -v set */
1190: debug_flag ? " -" : "",
1191: debug_flag, "vvv",
1192: /* Mandatory hostname */
1193: options.jump_host);
1194: debug("Setting implicit ProxyCommand from ProxyJump: %s",
1195: options.proxy_command);
1196: }
1.31 markus 1197:
1.400 djm 1198: if (options.port == 0)
1199: options.port = default_ssh_port();
1.463 djm 1200: channel_set_af(ssh, options.address_family);
1.196 djm 1201:
1.383 djm 1202: /* Tidy and check options */
1203: if (options.host_key_alias != NULL)
1204: lowercase(options.host_key_alias);
1205: if (options.proxy_command != NULL &&
1206: strcmp(options.proxy_command, "-") == 0 &&
1207: options.proxy_use_fdpass)
1208: fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
1.415 djm 1209: if (options.control_persist &&
1210: options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1211: debug("UpdateHostKeys=ask is incompatible with ControlPersist; "
1212: "disabling");
1213: options.update_hostkeys = 0;
1214: }
1.430 djm 1215: if (options.connection_attempts <= 0)
1216: fatal("Invalid number of ConnectionAttempts");
1217:
1.482 markus 1218: if (sshbuf_len(command) != 0 && options.remote_command != NULL)
1.461 bluhm 1219: fatal("Cannot execute command-line and remote command.");
1220:
1221: /* Cannot fork to background if no command. */
1.482 markus 1222: if (fork_after_authentication_flag && sshbuf_len(command) == 0 &&
1.461 bluhm 1223: options.remote_command == NULL && !no_shell_flag)
1224: fatal("Cannot fork into background without a command "
1225: "to execute.");
1226:
1.31 markus 1227: /* reinit */
1.452 dtucker 1228: log_init(argv0, options.log_level, options.log_facility, !use_syslog);
1.370 djm 1229:
1230: if (options.request_tty == REQUEST_TTY_YES ||
1231: options.request_tty == REQUEST_TTY_FORCE)
1232: tty_flag = 1;
1233:
1234: /* Allocate a tty by default if no command specified. */
1.482 markus 1235: if (sshbuf_len(command) == 0 && options.remote_command == NULL)
1.370 djm 1236: tty_flag = options.request_tty != REQUEST_TTY_NO;
1237:
1238: /* Force no tty */
1.447 markus 1239: if (options.request_tty == REQUEST_TTY_NO ||
1240: (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY))
1.370 djm 1241: tty_flag = 0;
1242: /* Do not allocate a tty if stdin is not a tty. */
1243: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
1244: options.request_tty != REQUEST_TTY_FORCE) {
1245: if (tty_flag)
1246: logit("Pseudo-terminal will not be allocated because "
1247: "stdin is not a terminal.");
1248: tty_flag = 0;
1249: }
1.31 markus 1250:
1251: if (options.user == NULL)
1252: options.user = xstrdup(pw->pw_name);
1.343 djm 1253:
1.466 djm 1254: /* Set up strings used to percent_expand() arguments */
1.358 djm 1255: if (gethostname(thishost, sizeof(thishost)) == -1)
1256: fatal("gethostname: %s", strerror(errno));
1257: strlcpy(shorthost, thishost, sizeof(shorthost));
1258: shorthost[strcspn(thishost, ".")] = '\0';
1259: snprintf(portstr, sizeof(portstr), "%d", options.port);
1.479 djm 1260: snprintf(uidstr, sizeof(uidstr), "%llu",
1261: (unsigned long long)pw->pw_uid);
1.358 djm 1262:
1.405 djm 1263: if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL ||
1264: ssh_digest_update(md, thishost, strlen(thishost)) < 0 ||
1265: ssh_digest_update(md, host, strlen(host)) < 0 ||
1266: ssh_digest_update(md, portstr, strlen(portstr)) < 0 ||
1267: ssh_digest_update(md, options.user, strlen(options.user)) < 0 ||
1268: ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0)
1269: fatal("%s: mux digest failed", __func__);
1270: ssh_digest_free(md);
1271: conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
1272:
1.466 djm 1273: /*
1274: * Expand tokens in arguments. NB. LocalCommand is expanded later,
1275: * after port-forwarding is set up, so it may pick up any local
1276: * tunnel interface name allocated.
1277: */
1.461 bluhm 1278: if (options.remote_command != NULL) {
1279: debug3("expanding RemoteCommand: %s", options.remote_command);
1280: cp = options.remote_command;
1281: options.remote_command = percent_expand(cp,
1282: "C", conn_hash_hex,
1283: "L", shorthost,
1284: "d", pw->pw_dir,
1285: "h", host,
1.479 djm 1286: "i", uidstr,
1.461 bluhm 1287: "l", thishost,
1288: "n", host_arg,
1289: "p", portstr,
1290: "r", options.user,
1291: "u", pw->pw_name,
1292: (char *)NULL);
1293: debug3("expanded RemoteCommand: %s", options.remote_command);
1294: free(cp);
1.482 markus 1295: if ((r = sshbuf_put(command, options.remote_command,
1296: strlen(options.remote_command))) != 0)
1297: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.304 dtucker 1298: }
1.31 markus 1299:
1.214 djm 1300: if (options.control_path != NULL) {
1.490 dtucker 1301: cp = tilde_expand_filename(options.control_path, getuid());
1.378 djm 1302: free(options.control_path);
1.405 djm 1303: options.control_path = percent_expand(cp,
1304: "C", conn_hash_hex,
1305: "L", shorthost,
1306: "h", host,
1.479 djm 1307: "i", uidstr,
1.405 djm 1308: "l", thishost,
1309: "n", host_arg,
1310: "p", portstr,
1311: "r", options.user,
1312: "u", pw->pw_name,
1.423 djm 1313: "i", uidstr,
1.358 djm 1314: (char *)NULL);
1.378 djm 1315: free(cp);
1.214 djm 1316: }
1.408 djm 1317:
1318: if (config_test) {
1319: dump_client_config(&options, host);
1320: exit(0);
1321: }
1.405 djm 1322:
1.312 djm 1323: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 1324: fatal("No ControlPath specified for \"-O\" command");
1.447 markus 1325: if (options.control_path != NULL) {
1326: int sock;
1327: if ((sock = muxclient(options.control_path)) >= 0) {
1.463 djm 1328: ssh_packet_set_connection(ssh, sock, sock);
1.499 djm 1329: ssh_packet_set_mux(ssh);
1.447 markus 1330: goto skip_connect;
1331: }
1332: }
1.401 djm 1333:
1334: /*
1335: * If hostname canonicalisation was not enabled, then we may not
1336: * have yet resolved the hostname. Do so now.
1337: */
1338: if (addrs == NULL && options.proxy_command == NULL) {
1.421 djm 1339: debug2("resolving \"%s\" port %d", host, options.port);
1.401 djm 1340: if ((addrs = resolve_host(host, options.port, 1,
1341: cname, sizeof(cname))) == NULL)
1342: cleanup_exit(255); /* resolve_host logs the error */
1343: }
1.214 djm 1344:
1.303 djm 1345: timeout_ms = options.connection_timeout * 1000;
1346:
1.77 markus 1347: /* Open a connection to the remote host. */
1.463 djm 1348: if (ssh_connect(ssh, host, addrs, &hostaddr, options.port,
1.385 djm 1349: options.address_family, options.connection_attempts,
1.488 dtucker 1350: &timeout_ms, options.tcp_keep_alive) != 0)
1.257 dtucker 1351: exit(255);
1.31 markus 1352:
1.391 djm 1353: if (addrs != NULL)
1354: freeaddrinfo(addrs);
1355:
1.499 djm 1356: ssh_packet_set_timeout(ssh, options.server_alive_interval,
1.385 djm 1357: options.server_alive_count_max);
1358:
1.303 djm 1359: if (timeout_ms > 0)
1360: debug3("timeout: %d ms remain after connect", timeout_ms);
1361:
1.33 markus 1362: /*
1.485 dtucker 1363: * If we successfully made the connection and we have hostbased auth
1364: * enabled, load the public keys so we can later use the ssh-keysign
1365: * helper to sign challenges.
1.33 markus 1366: */
1.112 markus 1367: sensitive_data.nkeys = 0;
1368: sensitive_data.keys = NULL;
1.457 djm 1369: if (options.hostbased_authentication) {
1.486 dtucker 1370: sensitive_data.nkeys = 10;
1.274 deraadt 1371: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.483 markus 1372: sizeof(struct sshkey));
1373:
1374: /* XXX check errors? */
1.486 dtucker 1375: #define L_PUBKEY(p,o) do { \
1376: if ((o) >= sensitive_data.nkeys) \
1377: fatal("%s pubkey out of array bounds", __func__); \
1.483 markus 1378: check_load(sshkey_load_public(p, &(sensitive_data.keys[o]), NULL), \
1.486 dtucker 1379: p, "pubkey"); \
1380: } while (0)
1381: #define L_CERT(p,o) do { \
1382: if ((o) >= sensitive_data.nkeys) \
1383: fatal("%s cert out of array bounds", __func__); \
1384: check_load(sshkey_load_cert(p, &(sensitive_data.keys[o])), p, "cert"); \
1385: } while (0)
1.177 markus 1386:
1.485 dtucker 1387: if (options.hostbased_authentication == 1) {
1.486 dtucker 1388: L_CERT(_PATH_HOST_ECDSA_KEY_FILE, 0);
1389: L_CERT(_PATH_HOST_ED25519_KEY_FILE, 1);
1390: L_CERT(_PATH_HOST_RSA_KEY_FILE, 2);
1391: L_CERT(_PATH_HOST_DSA_KEY_FILE, 3);
1392: L_PUBKEY(_PATH_HOST_ECDSA_KEY_FILE, 4);
1393: L_PUBKEY(_PATH_HOST_ED25519_KEY_FILE, 5);
1394: L_PUBKEY(_PATH_HOST_RSA_KEY_FILE, 6);
1395: L_PUBKEY(_PATH_HOST_DSA_KEY_FILE, 7);
1396: L_CERT(_PATH_HOST_XMSS_KEY_FILE, 8);
1397: L_PUBKEY(_PATH_HOST_XMSS_KEY_FILE, 9);
1.173 markus 1398: }
1.31 markus 1399: }
1400:
1.487 dtucker 1401: /* Create ~/.ssh * directory if it doesn't already exist. */
1.367 djm 1402: if (config == NULL) {
1403: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1404: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1405: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
1406: if (mkdir(buf, 0700) < 0)
1407: error("Could not create directory '%.200s'.",
1408: buf);
1409: }
1.31 markus 1410:
1.104 markus 1411: /* load options.identity_files */
1.466 djm 1412: load_public_identity_files(pw);
1.439 markus 1413:
1.476 djm 1414: /* optionally set the SSH_AUTHSOCKET_ENV_NAME variable */
1.440 markus 1415: if (options.identity_agent &&
1416: strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) {
1.439 markus 1417: if (strcmp(options.identity_agent, "none") == 0) {
1418: unsetenv(SSH_AUTHSOCKET_ENV_NAME);
1419: } else {
1420: p = tilde_expand_filename(options.identity_agent,
1.490 dtucker 1421: getuid());
1.479 djm 1422: cp = percent_expand(p,
1423: "d", pw->pw_dir,
1424: "h", host,
1425: "i", uidstr,
1426: "l", thishost,
1427: "r", options.user,
1428: "u", pw->pw_name,
1429: (char *)NULL);
1.494 djm 1430: free(p);
1431: /*
1432: * If identity_agent represents an environment variable
1433: * then recheck that it is valid (since processing with
1434: * percent_expand() may have changed it) and substitute
1435: * its value.
1436: */
1437: if (cp[0] == '$') {
1438: if (!valid_env_name(cp + 1)) {
1439: fatal("Invalid IdentityAgent "
1440: "environment variable name %s", cp);
1441: }
1442: if ((p = getenv(cp + 1)) == NULL)
1443: unsetenv(SSH_AUTHSOCKET_ENV_NAME);
1444: else
1445: setenv(SSH_AUTHSOCKET_ENV_NAME, p, 1);
1446: } else {
1447: /* identity_agent specifies a path directly */
1448: setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1);
1449: }
1.439 markus 1450: free(cp);
1451: }
1452: }
1.104 markus 1453:
1454: /* Expand ~ in known host file names. */
1.361 djm 1455: tilde_expand_paths(options.system_hostfiles,
1456: options.num_system_hostfiles);
1457: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 1458:
1459: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 1460: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 1461:
1.316 djm 1462: /* Log into the remote system. Never returns if the login fails. */
1.497 djm 1463: ssh_login(ssh, &sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 1464: options.port, pw, timeout_ms);
1.339 djm 1465:
1.499 djm 1466: if (ssh_packet_connection_is_on_socket(ssh)) {
1.339 djm 1467: verbose("Authenticated to %s ([%s]:%d).", host,
1.437 djm 1468: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.339 djm 1469: } else {
1470: verbose("Authenticated to %s (via proxy).", host);
1471: }
1.31 markus 1472:
1.112 markus 1473: /* We no longer need the private host keys. Clear them now. */
1474: if (sensitive_data.nkeys != 0) {
1475: for (i = 0; i < sensitive_data.nkeys; i++) {
1476: if (sensitive_data.keys[i] != NULL) {
1477: /* Destroys contents safely */
1478: debug3("clear hostkey %d", i);
1.483 markus 1479: sshkey_free(sensitive_data.keys[i]);
1.112 markus 1480: sensitive_data.keys[i] = NULL;
1481: }
1482: }
1.378 djm 1483: free(sensitive_data.keys);
1.134 markus 1484: }
1485: for (i = 0; i < options.num_identity_files; i++) {
1.378 djm 1486: free(options.identity_files[i]);
1487: options.identity_files[i] = NULL;
1.134 markus 1488: if (options.identity_keys[i]) {
1.483 markus 1489: sshkey_free(options.identity_keys[i]);
1.134 markus 1490: options.identity_keys[i] = NULL;
1491: }
1.112 markus 1492: }
1.426 djm 1493: for (i = 0; i < options.num_certificate_files; i++) {
1494: free(options.certificate_files[i]);
1495: options.certificate_files[i] = NULL;
1496: }
1.31 markus 1497:
1.447 markus 1498: skip_connect:
1.466 djm 1499: exit_status = ssh_session2(ssh, pw);
1.499 djm 1500: ssh_packet_close(ssh);
1.186 djm 1501:
1.312 djm 1502: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 1503: unlink(options.control_path);
1504:
1.353 djm 1505: /* Kill ProxyCommand if it is running. */
1506: ssh_kill_proxy_command();
1.186 djm 1507:
1.45 markus 1508: return exit_status;
1509: }
1510:
1.344 djm 1511: static void
1512: control_persist_detach(void)
1513: {
1514: pid_t pid;
1.438 djm 1515: int devnull, keep_stderr;
1.344 djm 1516:
1517: debug("%s: backgrounding master process", __func__);
1518:
1.473 djm 1519: /*
1520: * master (current process) into the background, and make the
1521: * foreground process a client of the backgrounded master.
1522: */
1.344 djm 1523: switch ((pid = fork())) {
1524: case -1:
1525: fatal("%s: fork: %s", __func__, strerror(errno));
1526: case 0:
1527: /* Child: master process continues mainloop */
1.473 djm 1528: break;
1529: default:
1.344 djm 1530: /* Parent: set up mux slave to connect to backgrounded master */
1531: debug2("%s: background process is %ld", __func__, (long)pid);
1532: stdin_null_flag = ostdin_null_flag;
1.359 djm 1533: options.request_tty = orequest_tty;
1.344 djm 1534: tty_flag = otty_flag;
1.473 djm 1535: close(muxserver_sock);
1536: muxserver_sock = -1;
1.351 markus 1537: options.control_master = SSHCTL_MASTER_NO;
1.473 djm 1538: muxclient(options.control_path);
1.344 djm 1539: /* muxclient() doesn't return on success. */
1.473 djm 1540: fatal("Failed to connect to new control master");
1541: }
1.346 djm 1542: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1543: error("%s: open(\"/dev/null\"): %s", __func__,
1544: strerror(errno));
1545: } else {
1.438 djm 1546: keep_stderr = log_is_on_stderr() && debug_flag;
1.346 djm 1547: if (dup2(devnull, STDIN_FILENO) == -1 ||
1.438 djm 1548: dup2(devnull, STDOUT_FILENO) == -1 ||
1549: (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1))
1.346 djm 1550: error("%s: dup2: %s", __func__, strerror(errno));
1551: if (devnull > STDERR_FILENO)
1552: close(devnull);
1553: }
1.381 djm 1554: daemon(1, 1);
1.362 djm 1555: setproctitle("%s [mux]", options.control_path);
1.344 djm 1556: }
1557:
1558: /* Do fork() after authentication. Used by "ssh -f" */
1559: static void
1560: fork_postauth(void)
1561: {
1562: if (need_controlpersist_detach)
1563: control_persist_detach();
1564: debug("forking to background");
1565: fork_after_authentication_flag = 0;
1566: if (daemon(1, 1) < 0)
1567: fatal("daemon() failed: %.200s", strerror(errno));
1568: }
1569:
1.315 djm 1570: /* Callback for remote forward global requests */
1571: static void
1.463 djm 1572: ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt)
1.315 djm 1573: {
1.406 millert 1574: struct Forward *rfwd = (struct Forward *)ctxt;
1.499 djm 1575: u_int port;
1576: int r;
1.315 djm 1577:
1.324 djm 1578: /* XXX verbose() on failure? */
1.404 markus 1579: debug("remote forward %s for: listen %s%s%d, connect %s:%d",
1.315 djm 1580: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1.406 millert 1581: rfwd->listen_path ? rfwd->listen_path :
1582: rfwd->listen_host ? rfwd->listen_host : "",
1583: (rfwd->listen_path || rfwd->listen_host) ? ":" : "",
1584: rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
1585: rfwd->connect_host, rfwd->connect_port);
1586: if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
1.366 markus 1587: if (type == SSH2_MSG_REQUEST_SUCCESS) {
1.499 djm 1588: if ((r = sshpkt_get_u32(ssh, &port)) != 0)
1589: fatal("%s: %s", __func__, ssh_err(r));
1590: if (port > 65535) {
1591: error("Invalid allocated port %u for remote "
1592: "forward to %s:%d", port,
1593: rfwd->connect_host, rfwd->connect_port);
1594: /* Ensure failure processing runs below */
1595: type = SSH2_MSG_REQUEST_FAILURE;
1596: channel_update_permission(ssh,
1597: rfwd->handle, -1);
1598: } else {
1599: rfwd->allocated_port = (int)port;
1600: logit("Allocated port %u for remote "
1601: "forward to %s:%d",
1602: rfwd->allocated_port, rfwd->connect_host,
1603: rfwd->connect_port);
1604: channel_update_permission(ssh,
1605: rfwd->handle, rfwd->allocated_port);
1606: }
1.366 markus 1607: } else {
1.480 djm 1608: channel_update_permission(ssh, rfwd->handle, -1);
1.366 markus 1609: }
1.324 djm 1610: }
1.468 djm 1611:
1.315 djm 1612: if (type == SSH2_MSG_REQUEST_FAILURE) {
1.406 millert 1613: if (options.exit_on_forward_failure) {
1614: if (rfwd->listen_path != NULL)
1615: fatal("Error: remote port forwarding failed "
1616: "for listen path %s", rfwd->listen_path);
1617: else
1618: fatal("Error: remote port forwarding failed "
1619: "for listen port %d", rfwd->listen_port);
1620: } else {
1621: if (rfwd->listen_path != NULL)
1622: logit("Warning: remote port forwarding failed "
1623: "for listen path %s", rfwd->listen_path);
1624: else
1625: logit("Warning: remote port forwarding failed "
1626: "for listen port %d", rfwd->listen_port);
1627: }
1.315 djm 1628: }
1.318 djm 1629: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 1630: debug("All remote forwarding requests processed");
1.344 djm 1631: if (fork_after_authentication_flag)
1632: fork_postauth();
1.318 djm 1633: }
1.315 djm 1634: }
1635:
1.126 itojun 1636: static void
1.463 djm 1637: client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg)
1.331 dtucker 1638: {
1639: debug("stdio forwarding: done");
1640: cleanup_exit(0);
1641: }
1642:
1.368 djm 1643: static void
1.463 djm 1644: ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg)
1.407 djm 1645: {
1646: if (!success)
1647: fatal("stdio forwarding failed");
1648: }
1649:
1650: static void
1.463 djm 1651: ssh_init_stdio_forwarding(struct ssh *ssh)
1.331 dtucker 1652: {
1653: Channel *c;
1.332 djm 1654: int in, out;
1.331 dtucker 1655:
1.441 dtucker 1656: if (options.stdio_forward_host == NULL)
1.368 djm 1657: return;
1658:
1.441 dtucker 1659: debug3("%s: %s:%d", __func__, options.stdio_forward_host,
1660: options.stdio_forward_port);
1.332 djm 1661:
1.368 djm 1662: if ((in = dup(STDIN_FILENO)) < 0 ||
1663: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1664: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.463 djm 1665: if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host,
1.441 dtucker 1666: options.stdio_forward_port, in, out)) == NULL)
1.368 djm 1667: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.463 djm 1668: channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0);
1669: channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL);
1.331 dtucker 1670: }
1671:
1672: static void
1.466 djm 1673: ssh_init_forwarding(struct ssh *ssh, char **ifname)
1.70 markus 1674: {
1.86 markus 1675: int success = 0;
1.70 markus 1676: int i;
1.331 dtucker 1677:
1.70 markus 1678: /* Initiate local TCP/IP port forwardings. */
1679: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1680: debug("Local connections to %.200s:%d forwarded to remote "
1681: "address %.200s:%d",
1.406 millert 1682: (options.local_forwards[i].listen_path != NULL) ?
1683: options.local_forwards[i].listen_path :
1.234 deraadt 1684: (options.local_forwards[i].listen_host == NULL) ?
1.406 millert 1685: (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1686: options.local_forwards[i].listen_host,
1687: options.local_forwards[i].listen_port,
1.406 millert 1688: (options.local_forwards[i].connect_path != NULL) ?
1689: options.local_forwards[i].connect_path :
1.232 djm 1690: options.local_forwards[i].connect_host,
1691: options.local_forwards[i].connect_port);
1.463 djm 1692: success += channel_setup_local_fwd_listener(ssh,
1.406 millert 1693: &options.local_forwards[i], &options.fwd_opts);
1.70 markus 1694: }
1.283 markus 1695: if (i > 0 && success != i && options.exit_on_forward_failure)
1696: fatal("Could not request local forwarding.");
1.86 markus 1697: if (i > 0 && success == 0)
1698: error("Could not request local forwarding.");
1.70 markus 1699:
1700: /* Initiate remote TCP/IP port forwardings. */
1701: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1702: debug("Remote connections from %.200s:%d forwarded to "
1703: "local address %.200s:%d",
1.406 millert 1704: (options.remote_forwards[i].listen_path != NULL) ?
1705: options.remote_forwards[i].listen_path :
1.248 djm 1706: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1707: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1708: options.remote_forwards[i].listen_port,
1.406 millert 1709: (options.remote_forwards[i].connect_path != NULL) ?
1710: options.remote_forwards[i].connect_path :
1.232 djm 1711: options.remote_forwards[i].connect_host,
1712: options.remote_forwards[i].connect_port);
1.366 markus 1713: options.remote_forwards[i].handle =
1.463 djm 1714: channel_request_remote_forwarding(ssh,
1.406 millert 1715: &options.remote_forwards[i]);
1.366 markus 1716: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1717: if (options.exit_on_forward_failure)
1718: fatal("Could not request remote forwarding.");
1719: else
1720: logit("Warning: Could not request remote "
1721: "forwarding.");
1.366 markus 1722: } else {
1.463 djm 1723: client_register_global_confirm(
1724: ssh_confirm_remote_forward,
1.366 markus 1725: &options.remote_forwards[i]);
1.283 markus 1726: }
1.70 markus 1727: }
1.301 djm 1728:
1729: /* Initiate tunnel forwarding. */
1730: if (options.tun_open != SSH_TUNMODE_NO) {
1.466 djm 1731: if ((*ifname = client_request_tun_fwd(ssh,
1732: options.tun_open, options.tun_local,
1733: options.tun_remote)) == NULL) {
1.301 djm 1734: if (options.exit_on_forward_failure)
1735: fatal("Could not request tunnel forwarding.");
1736: else
1737: error("Could not request tunnel forwarding.");
1738: }
1.468 djm 1739: }
1.70 markus 1740: }
1741:
1.126 itojun 1742: static void
1.70 markus 1743: check_agent_present(void)
1744: {
1.412 djm 1745: int r;
1746:
1.70 markus 1747: if (options.forward_agent) {
1.254 djm 1748: /* Clear agent forwarding if we don't have an agent. */
1.412 djm 1749: if ((r = ssh_get_authentication_socket(NULL)) != 0) {
1.70 markus 1750: options.forward_agent = 0;
1.412 djm 1751: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1752: debug("ssh_get_authentication_socket: %s",
1753: ssh_err(r));
1754: }
1.70 markus 1755: }
1756: }
1757:
1.214 djm 1758: static void
1.463 djm 1759: ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg)
1.214 djm 1760: {
1.215 djm 1761: extern char **environ;
1.243 djm 1762: const char *display;
1.499 djm 1763: int r, interactive = tty_flag;
1.433 djm 1764: char *proto = NULL, *data = NULL;
1.337 djm 1765:
1766: if (!success)
1767: return; /* No need for error message, channels code sens one */
1.215 djm 1768:
1.248 djm 1769: display = getenv("DISPLAY");
1.417 djm 1770: if (display == NULL && options.forward_x11)
1771: debug("X11 forwarding requested but DISPLAY not set");
1.463 djm 1772: if (options.forward_x11 && client_x11_get_proto(ssh, display,
1.433 djm 1773: options.xauth_location, options.forward_x11_trusted,
1774: options.forward_x11_timeout, &proto, &data) == 0) {
1.50 markus 1775: /* Request forwarding with authentication spoofing. */
1.316 djm 1776: debug("Requesting X11 forwarding with authentication "
1777: "spoofing.");
1.463 djm 1778: x11_request_forwarding_with_spoofing(ssh, id, display, proto,
1.363 djm 1779: data, 1);
1.463 djm 1780: client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN);
1.363 djm 1781: /* XXX exit_on_forward_failure */
1.80 markus 1782: interactive = 1;
1.50 markus 1783: }
1784:
1.70 markus 1785: check_agent_present();
1786: if (options.forward_agent) {
1787: debug("Requesting authentication agent forwarding.");
1.463 djm 1788: channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0);
1.499 djm 1789: if ((r = sshpkt_send(ssh)) != 0)
1790: fatal("%s: %s", __func__, ssh_err(r));
1.212 djm 1791: }
1.369 dtucker 1792:
1793: /* Tell the packet module whether this is an interactive session. */
1.499 djm 1794: ssh_packet_set_interactive(ssh, interactive,
1.369 dtucker 1795: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1796:
1.463 djm 1797: client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"),
1.482 markus 1798: NULL, fileno(stdin), command, environ);
1.45 markus 1799: }
1800:
1.143 markus 1801: /* open new channel for a session */
1.126 itojun 1802: static int
1.463 djm 1803: ssh_session2_open(struct ssh *ssh)
1.45 markus 1804: {
1.118 markus 1805: Channel *c;
1806: int window, packetmax, in, out, err;
1.60 markus 1807:
1.62 markus 1808: if (stdin_null_flag) {
1.93 itojun 1809: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1810: } else {
1811: in = dup(STDIN_FILENO);
1812: }
1.60 markus 1813: out = dup(STDOUT_FILENO);
1814: err = dup(STDERR_FILENO);
1.45 markus 1815:
1816: if (in < 0 || out < 0 || err < 0)
1.62 markus 1817: fatal("dup() in/out/err failed");
1.45 markus 1818:
1.69 markus 1819: /* enable nonblocking unless tty */
1820: if (!isatty(in))
1821: set_nonblock(in);
1822: if (!isatty(out))
1823: set_nonblock(out);
1824: if (!isatty(err))
1825: set_nonblock(err);
1826:
1.65 markus 1827: window = CHAN_SES_WINDOW_DEFAULT;
1828: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1829: if (tty_flag) {
1830: window >>= 1;
1831: packetmax >>= 1;
1.45 markus 1832: }
1.463 djm 1833: c = channel_new(ssh,
1.45 markus 1834: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1835: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1836: "client-session", /*nonblock*/0);
1.45 markus 1837:
1.463 djm 1838: debug3("%s: channel_new: %d", __func__, c->self);
1.106 markus 1839:
1.463 djm 1840: channel_send_open(ssh, c->self);
1.143 markus 1841: if (!no_shell_flag)
1.463 djm 1842: channel_register_open_confirm(ssh, c->self,
1.310 djm 1843: ssh_session2_setup, NULL);
1.106 markus 1844:
1.118 markus 1845: return c->self;
1.106 markus 1846: }
1847:
1.126 itojun 1848: static int
1.466 djm 1849: ssh_session2(struct ssh *ssh, struct passwd *pw)
1.106 markus 1850: {
1.499 djm 1851: int r, devnull, id = -1;
1.466 djm 1852: char *cp, *tun_fwd_ifname = NULL;
1.106 markus 1853:
1854: /* XXX should be pre-session */
1.368 djm 1855: if (!options.control_persist)
1.463 djm 1856: ssh_init_stdio_forwarding(ssh);
1.466 djm 1857:
1858: ssh_init_forwarding(ssh, &tun_fwd_ifname);
1859:
1860: if (options.local_command != NULL) {
1861: debug3("expanding LocalCommand: %s", options.local_command);
1862: cp = options.local_command;
1863: options.local_command = percent_expand(cp,
1864: "C", conn_hash_hex,
1865: "L", shorthost,
1866: "d", pw->pw_dir,
1867: "h", host,
1.479 djm 1868: "i", uidstr,
1.466 djm 1869: "l", thishost,
1870: "n", host_arg,
1871: "p", portstr,
1872: "r", options.user,
1873: "u", pw->pw_name,
1874: "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname,
1875: (char *)NULL);
1876: debug3("expanded LocalCommand: %s", options.local_command);
1877: free(cp);
1878: }
1.106 markus 1879:
1.344 djm 1880: /* Start listening for multiplex clients */
1.499 djm 1881: if (!ssh_packet_get_mux(ssh))
1.463 djm 1882: muxserver_listen(ssh);
1.344 djm 1883:
1.473 djm 1884: /*
1.368 djm 1885: * If we are in control persist mode and have a working mux listen
1886: * socket, then prepare to background ourselves and have a foreground
1887: * client attach as a control slave.
1888: * NB. we must save copies of the flags that we override for
1.344 djm 1889: * the backgrounding, since we defer attachment of the slave until
1890: * after the connection is fully established (in particular,
1891: * async rfwd replies have been received for ExitOnForwardFailure).
1892: */
1.473 djm 1893: if (options.control_persist && muxserver_sock != -1) {
1.344 djm 1894: ostdin_null_flag = stdin_null_flag;
1895: ono_shell_flag = no_shell_flag;
1.359 djm 1896: orequest_tty = options.request_tty;
1.344 djm 1897: otty_flag = tty_flag;
1.473 djm 1898: stdin_null_flag = 1;
1899: no_shell_flag = 1;
1900: tty_flag = 0;
1.344 djm 1901: if (!fork_after_authentication_flag)
1902: need_controlpersist_detach = 1;
1903: fork_after_authentication_flag = 1;
1.473 djm 1904: }
1.368 djm 1905: /*
1906: * ControlPersist mux listen socket setup failed, attempt the
1907: * stdio forward setup that we skipped earlier.
1908: */
1909: if (options.control_persist && muxserver_sock == -1)
1.463 djm 1910: ssh_init_stdio_forwarding(ssh);
1.344 djm 1911:
1.471 djm 1912: if (!no_shell_flag)
1.463 djm 1913: id = ssh_session2_open(ssh);
1.379 djm 1914: else {
1.499 djm 1915: ssh_packet_set_interactive(ssh,
1.379 djm 1916: options.control_master == SSHCTL_MASTER_NO,
1917: options.ip_qos_interactive, options.ip_qos_bulk);
1918: }
1.314 djm 1919:
1920: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1921: if (options.control_master == SSHCTL_MASTER_NO &&
1922: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1923: debug("Requesting no-more-sessions@openssh.com");
1.499 djm 1924: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
1925: (r = sshpkt_put_cstring(ssh,
1926: "no-more-sessions@openssh.com")) != 0 ||
1927: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1928: (r = sshpkt_send(ssh)) != 0)
1929: fatal("%s: %s", __func__, ssh_err(r));
1.314 djm 1930: }
1.255 reyk 1931:
1932: /* Execute a local command */
1933: if (options.local_command != NULL &&
1934: options.permit_local_command)
1935: ssh_local_cmd(options.local_command);
1.467 djm 1936:
1937: /*
1938: * stdout is now owned by the session channel; clobber it here
1939: * so future channel closes are propagated to the local fd.
1940: * NB. this can only happen after LocalCommand has completed,
1941: * as it may want to write to stdout.
1942: */
1.469 djm 1943: if (!need_controlpersist_detach) {
1944: if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1)
1945: error("%s: open %s: %s", __func__,
1946: _PATH_DEVNULL, strerror(errno));
1947: if (dup2(devnull, STDOUT_FILENO) < 0)
1948: fatal("%s: dup2() stdout failed", __func__);
1949: if (devnull > STDERR_FILENO)
1950: close(devnull);
1951: }
1.301 djm 1952:
1.342 djm 1953: /*
1954: * If requested and we are not interested in replies to remote
1955: * forwarding requests, then let ssh continue in the background.
1956: */
1.344 djm 1957: if (fork_after_authentication_flag) {
1958: if (options.exit_on_forward_failure &&
1959: options.num_remote_forwards > 0) {
1960: debug("deferring postauth fork until remote forward "
1961: "confirmation received");
1962: } else
1963: fork_postauth();
1.318 djm 1964: }
1.31 markus 1965:
1.463 djm 1966: return client_loop(ssh, tty_flag, tty_flag ?
1.119 stevesk 1967: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1968: }
1969:
1.426 djm 1970: /* Loads all IdentityFile and CertificateFile keys */
1.126 itojun 1971: static void
1.466 djm 1972: load_public_identity_files(struct passwd *pw)
1.104 markus 1973: {
1.466 djm 1974: char *filename, *cp;
1.460 markus 1975: struct sshkey *public;
1.426 djm 1976: int i;
1977: u_int n_ids, n_certs;
1.335 djm 1978: char *identity_files[SSH_MAX_IDENTITY_FILES];
1.460 markus 1979: struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
1.484 djm 1980: int identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
1.426 djm 1981: char *certificate_files[SSH_MAX_CERTIFICATE_FILES];
1982: struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
1.484 djm 1983: int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
1.333 markus 1984: #ifdef ENABLE_PKCS11
1.460 markus 1985: struct sshkey **keys;
1.333 markus 1986: int nkeys;
1.335 djm 1987: #endif /* PKCS11 */
1.104 markus 1988:
1.426 djm 1989: n_ids = n_certs = 0;
1.398 tedu 1990: memset(identity_files, 0, sizeof(identity_files));
1991: memset(identity_keys, 0, sizeof(identity_keys));
1.484 djm 1992: memset(identity_file_userprovided, 0,
1993: sizeof(identity_file_userprovided));
1.426 djm 1994: memset(certificate_files, 0, sizeof(certificate_files));
1995: memset(certificates, 0, sizeof(certificates));
1.484 djm 1996: memset(certificate_file_userprovided, 0,
1997: sizeof(certificate_file_userprovided));
1.335 djm 1998:
1999: #ifdef ENABLE_PKCS11
1.333 markus 2000: if (options.pkcs11_provider != NULL &&
1.167 markus 2001: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 2002: (pkcs11_init(!options.batch_mode) == 0) &&
2003: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
2004: &keys)) > 0) {
2005: for (i = 0; i < nkeys; i++) {
1.335 djm 2006: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1.483 markus 2007: sshkey_free(keys[i]);
1.335 djm 2008: continue;
2009: }
2010: identity_keys[n_ids] = keys[i];
2011: identity_files[n_ids] =
1.333 markus 2012: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 2013: n_ids++;
1.167 markus 2014: }
1.378 djm 2015: free(keys);
1.127 markus 2016: }
1.333 markus 2017: #endif /* ENABLE_PKCS11 */
1.335 djm 2018: for (i = 0; i < options.num_identity_files; i++) {
1.373 djm 2019: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
2020: strcasecmp(options.identity_files[i], "none") == 0) {
1.378 djm 2021: free(options.identity_files[i]);
1.426 djm 2022: options.identity_files[i] = NULL;
1.335 djm 2023: continue;
2024: }
1.490 dtucker 2025: cp = tilde_expand_filename(options.identity_files[i], getuid());
1.466 djm 2026: filename = percent_expand(cp, "d", pw->pw_dir,
2027: "u", pw->pw_name, "l", thishost, "h", host,
1.275 djm 2028: "r", options.user, (char *)NULL);
1.378 djm 2029: free(cp);
1.483 markus 2030: check_load(sshkey_load_public(filename, &public, NULL),
2031: filename, "pubkey");
1.131 millert 2032: debug("identity file %s type %d", filename,
2033: public ? public->type : -1);
1.378 djm 2034: free(options.identity_files[i]);
1.335 djm 2035: identity_files[n_ids] = filename;
2036: identity_keys[n_ids] = public;
1.484 djm 2037: identity_file_userprovided[n_ids] =
2038: options.identity_file_userprovided[i];
1.335 djm 2039: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
2040: continue;
2041:
1.426 djm 2042: /*
2043: * If no certificates have been explicitly listed then try
2044: * to add the default certificate variant too.
2045: */
2046: if (options.num_certificate_files != 0)
2047: continue;
1.335 djm 2048: xasprintf(&cp, "%s-cert", filename);
1.483 markus 2049: check_load(sshkey_load_public(cp, &public, NULL),
2050: filename, "pubkey");
1.335 djm 2051: debug("identity file %s type %d", cp,
2052: public ? public->type : -1);
2053: if (public == NULL) {
1.378 djm 2054: free(cp);
1.335 djm 2055: continue;
2056: }
1.483 markus 2057: if (!sshkey_is_cert(public)) {
1.335 djm 2058: debug("%s: key %s type %s is not a certificate",
1.483 markus 2059: __func__, cp, sshkey_type(public));
2060: sshkey_free(public);
1.378 djm 2061: free(cp);
1.335 djm 2062: continue;
2063: }
1.448 djm 2064: /* NB. leave filename pointing to private key */
2065: identity_files[n_ids] = xstrdup(filename);
1.335 djm 2066: identity_keys[n_ids] = public;
1.484 djm 2067: identity_file_userprovided[n_ids] =
2068: options.identity_file_userprovided[i];
1.335 djm 2069: n_ids++;
2070: }
1.426 djm 2071:
2072: if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES)
2073: fatal("%s: too many certificates", __func__);
2074: for (i = 0; i < options.num_certificate_files; i++) {
2075: cp = tilde_expand_filename(options.certificate_files[i],
1.490 dtucker 2076: getuid());
1.479 djm 2077: filename = percent_expand(cp,
2078: "d", pw->pw_dir,
2079: "h", host,
1.481 djm 2080: "i", uidstr,
1.479 djm 2081: "l", thishost,
2082: "r", options.user,
2083: "u", pw->pw_name,
2084: (char *)NULL);
1.426 djm 2085: free(cp);
2086:
1.483 markus 2087: check_load(sshkey_load_public(filename, &public, NULL),
2088: filename, "certificate");
1.426 djm 2089: debug("certificate file %s type %d", filename,
2090: public ? public->type : -1);
2091: free(options.certificate_files[i]);
2092: options.certificate_files[i] = NULL;
2093: if (public == NULL) {
2094: free(filename);
2095: continue;
2096: }
1.483 markus 2097: if (!sshkey_is_cert(public)) {
1.426 djm 2098: debug("%s: key %s type %s is not a certificate",
1.483 markus 2099: __func__, filename, sshkey_type(public));
2100: sshkey_free(public);
1.426 djm 2101: free(filename);
2102: continue;
2103: }
2104: certificate_files[n_certs] = filename;
2105: certificates[n_certs] = public;
1.484 djm 2106: certificate_file_userprovided[n_certs] =
2107: options.certificate_file_userprovided[i];
1.426 djm 2108: ++n_certs;
2109: }
2110:
1.335 djm 2111: options.num_identity_files = n_ids;
2112: memcpy(options.identity_files, identity_files, sizeof(identity_files));
2113: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1.484 djm 2114: memcpy(options.identity_file_userprovided,
2115: identity_file_userprovided, sizeof(identity_file_userprovided));
1.426 djm 2116:
2117: options.num_certificate_files = n_certs;
2118: memcpy(options.certificate_files,
2119: certificate_files, sizeof(certificate_files));
2120: memcpy(options.certificates, certificates, sizeof(certificates));
1.484 djm 2121: memcpy(options.certificate_file_userprovided,
2122: certificate_file_userprovided,
2123: sizeof(certificate_file_userprovided));
1.214 djm 2124: }
1.352 djm 2125:
2126: static void
2127: main_sigchld_handler(int sig)
2128: {
2129: int save_errno = errno;
2130: pid_t pid;
2131: int status;
2132:
2133: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
2134: (pid < 0 && errno == EINTR))
2135: ;
2136: errno = save_errno;
2137: }