Annotation of src/usr.bin/ssh/ssh.c, Revision 1.486
1.486 ! dtucker 1: /* $OpenBSD: ssh.c,v 1.485 2018/07/16 11:05:41 dtucker 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"
1.225 dtucker 97: #include "uidswap.h"
1.278 stevesk 98: #include "version.h"
1.412 djm 99: #include "ssherr.h"
1.420 djm 100: #include "myproposal.h"
1.49 markus 101:
1.333 markus 102: #ifdef ENABLE_PKCS11
103: #include "ssh-pkcs11.h"
1.137 jakob 104: #endif
1.127 markus 105:
1.49 markus 106: extern char *__progname;
1.1 deraadt 107:
1.316 djm 108: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 109: int debug_flag = 0;
110:
1.359 djm 111: /* Flag indicating whether a tty should be requested */
1.1 deraadt 112: int tty_flag = 0;
113:
1.45 markus 114: /* don't exec a shell */
115: int no_shell_flag = 0;
116:
1.33 markus 117: /*
118: * Flag indicating that nothing should be read from stdin. This can be set
119: * on the command line.
120: */
1.1 deraadt 121: int stdin_null_flag = 0;
122:
1.33 markus 123: /*
1.344 djm 124: * Flag indicating that the current process should be backgrounded and
125: * a new slave launched in the foreground for ControlPersist.
126: */
127: int need_controlpersist_detach = 0;
128:
129: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 130: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 131:
132: /*
1.33 markus 133: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 134: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 135: * background.
136: */
1.1 deraadt 137: int fork_after_authentication_flag = 0;
138:
1.33 markus 139: /*
140: * General data structure for command line options and options configurable
141: * in configuration files. See readconf.h.
142: */
1.1 deraadt 143: Options options;
144:
1.139 markus 145: /* optional user configfile */
146: char *config = NULL;
147:
1.33 markus 148: /*
149: * Name of the host we are connecting to. This is the name given on the
150: * command line, or the HostName specified for the user-supplied name in a
151: * configuration file.
152: */
1.1 deraadt 153: char *host;
154:
1.466 djm 155: /* Various strings used to to percent_expand() arguments */
156: static char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
157: static char uidstr[32], *host_arg, *conn_hash_hex;
158:
1.22 provos 159: /* socket address the host resolves to */
1.37 markus 160: struct sockaddr_storage hostaddr;
1.1 deraadt 161:
1.112 markus 162: /* Private host keys. */
1.173 markus 163: Sensitive sensitive_data;
1.1 deraadt 164:
1.10 dugsong 165: /* Original real UID. */
166: uid_t original_real_uid;
1.177 markus 167: uid_t original_effective_uid;
1.1 deraadt 168:
1.45 markus 169: /* command to be executed */
1.482 markus 170: struct sshbuf *command;
1.45 markus 171:
1.85 djm 172: /* Should we execute a command or invoke a subsystem? */
173: int subsystem_flag = 0;
174:
1.170 markus 175: /* # of replies received for global requests */
1.315 djm 176: static int remote_forward_confirms_received = 0;
1.170 markus 177:
1.313 djm 178: /* mux.c */
179: extern int muxserver_sock;
180: extern u_int muxclient_command;
181:
1.1 deraadt 182: /* Prints a help message to the user. This function never returns. */
183:
1.126 itojun 184: static void
1.93 itojun 185: usage(void)
1.1 deraadt 186: {
1.208 markus 187: fprintf(stderr,
1.474 djm 188: "usage: ssh [-46AaCfGgKkMNnqsTtVvXxYy] [-B bind_interface]\n"
189: " [-b bind_address] [-c cipher_spec] [-D [bind_address:]port]\n"
190: " [-E log_file] [-e escape_char] [-F configfile] [-I pkcs11]\n"
191: " [-i identity_file] [-J [user@]host[:port]] [-L address]\n"
192: " [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port]\n"
193: " [-Q query_option] [-R address] [-S ctl_path] [-W host:port]\n"
194: " [-w local_tun[:remote_tun]] destination [command]\n"
1.208 markus 195: );
1.257 dtucker 196: exit(255);
1.1 deraadt 197: }
198:
1.466 djm 199: static int ssh_session2(struct ssh *, struct passwd *);
200: static void load_public_identity_files(struct passwd *);
1.352 djm 201: static void main_sigchld_handler(int);
1.312 djm 202:
1.361 djm 203: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
204: static void
205: tilde_expand_paths(char **paths, u_int num_paths)
206: {
207: u_int i;
208: char *cp;
209:
210: for (i = 0; i < num_paths; i++) {
211: cp = tilde_expand_filename(paths[i], original_real_uid);
1.378 djm 212: free(paths[i]);
1.361 djm 213: paths[i] = cp;
214: }
215: }
216:
1.400 djm 217: /*
218: * Attempt to resolve a host name / port to a set of addresses and
219: * optionally return any CNAMEs encountered along the way.
220: * Returns NULL on failure.
221: * NB. this function must operate with a options having undefined members.
222: */
1.385 djm 223: static struct addrinfo *
1.400 djm 224: resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
1.385 djm 225: {
226: char strport[NI_MAXSERV];
227: struct addrinfo hints, *res;
228: int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1;
229:
1.400 djm 230: if (port <= 0)
231: port = default_ssh_port();
232:
1.427 djm 233: snprintf(strport, sizeof strport, "%d", port);
1.398 tedu 234: memset(&hints, 0, sizeof(hints));
1.400 djm 235: hints.ai_family = options.address_family == -1 ?
236: AF_UNSPEC : options.address_family;
1.385 djm 237: hints.ai_socktype = SOCK_STREAM;
238: if (cname != NULL)
239: hints.ai_flags = AI_CANONNAME;
240: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
241: if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
242: loglevel = SYSLOG_LEVEL_ERROR;
243: do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
244: __progname, name, ssh_gai_strerror(gaierr));
245: return NULL;
246: }
247: if (cname != NULL && res->ai_canonname != NULL) {
248: if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
249: error("%s: host \"%s\" cname \"%s\" too long (max %lu)",
250: __func__, name, res->ai_canonname, (u_long)clen);
251: if (clen > 0)
252: *cname = '\0';
253: }
254: }
255: return res;
256: }
257:
1.470 djm 258: /* Returns non-zero if name can only be an address and not a hostname */
259: static int
260: is_addr_fast(const char *name)
261: {
262: return (strchr(name, '%') != NULL || strchr(name, ':') != NULL ||
263: strspn(name, "0123456789.") == strlen(name));
264: }
265:
266: /* Returns non-zero if name represents a valid, single address */
267: static int
268: is_addr(const char *name)
269: {
270: char strport[NI_MAXSERV];
271: struct addrinfo hints, *res;
272:
273: if (is_addr_fast(name))
274: return 1;
275:
276: snprintf(strport, sizeof strport, "%u", default_ssh_port());
277: memset(&hints, 0, sizeof(hints));
278: hints.ai_family = options.address_family == -1 ?
279: AF_UNSPEC : options.address_family;
280: hints.ai_socktype = SOCK_STREAM;
281: hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
282: if (getaddrinfo(name, strport, &hints, &res) != 0)
283: return 0;
284: if (res == NULL || res->ai_next != NULL) {
285: freeaddrinfo(res);
286: return 0;
287: }
288: freeaddrinfo(res);
289: return 1;
290: }
291:
1.385 djm 292: /*
1.413 djm 293: * Attempt to resolve a numeric host address / port to a single address.
294: * Returns a canonical address string.
295: * Returns NULL on failure.
296: * NB. this function must operate with a options having undefined members.
297: */
298: static struct addrinfo *
299: resolve_addr(const char *name, int port, char *caddr, size_t clen)
300: {
301: char addr[NI_MAXHOST], strport[NI_MAXSERV];
302: struct addrinfo hints, *res;
303: int gaierr;
304:
305: if (port <= 0)
306: port = default_ssh_port();
307: snprintf(strport, sizeof strport, "%u", port);
308: memset(&hints, 0, sizeof(hints));
309: hints.ai_family = options.address_family == -1 ?
310: AF_UNSPEC : options.address_family;
311: hints.ai_socktype = SOCK_STREAM;
312: hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
313: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
314: debug2("%s: could not resolve name %.100s as address: %s",
315: __func__, name, ssh_gai_strerror(gaierr));
316: return NULL;
317: }
318: if (res == NULL) {
319: debug("%s: getaddrinfo %.100s returned no addresses",
320: __func__, name);
321: return NULL;
322: }
323: if (res->ai_next != NULL) {
324: debug("%s: getaddrinfo %.100s returned multiple addresses",
325: __func__, name);
326: goto fail;
327: }
328: if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
329: addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
330: debug("%s: Could not format address for name %.100s: %s",
331: __func__, name, ssh_gai_strerror(gaierr));
332: goto fail;
333: }
334: if (strlcpy(caddr, addr, clen) >= clen) {
335: error("%s: host \"%s\" addr \"%s\" too long (max %lu)",
336: __func__, name, addr, (u_long)clen);
337: if (clen > 0)
338: *caddr = '\0';
339: fail:
340: freeaddrinfo(res);
341: return NULL;
342: }
343: return res;
344: }
345:
346: /*
1.385 djm 347: * Check whether the cname is a permitted replacement for the hostname
348: * and perform the replacement if it is.
1.400 djm 349: * NB. this function must operate with a options having undefined members.
1.385 djm 350: */
351: static int
1.443 djm 352: check_follow_cname(int direct, char **namep, const char *cname)
1.385 djm 353: {
354: int i;
355: struct allowed_cname *rule;
356:
357: if (*cname == '\0' || options.num_permitted_cnames == 0 ||
358: strcmp(*namep, cname) == 0)
359: return 0;
1.386 djm 360: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
1.385 djm 361: return 0;
362: /*
1.386 djm 363: * Don't attempt to canonicalize names that will be interpreted by
1.443 djm 364: * a proxy or jump host unless the user specifically requests so.
1.385 djm 365: */
1.443 djm 366: if (!direct &&
1.386 djm 367: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
1.385 djm 368: return 0;
369: debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname);
370: for (i = 0; i < options.num_permitted_cnames; i++) {
371: rule = options.permitted_cnames + i;
1.418 djm 372: if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
373: match_pattern_list(cname, rule->target_list, 1) != 1)
1.385 djm 374: continue;
1.386 djm 375: verbose("Canonicalized DNS aliased hostname "
1.385 djm 376: "\"%s\" => \"%s\"", *namep, cname);
377: free(*namep);
378: *namep = xstrdup(cname);
379: return 1;
380: }
381: return 0;
382: }
383:
384: /*
385: * Attempt to resolve the supplied hostname after applying the user's
1.387 djm 386: * canonicalization rules. Returns the address list for the host or NULL
387: * if no name was found after canonicalization.
1.400 djm 388: * NB. this function must operate with a options having undefined members.
1.385 djm 389: */
390: static struct addrinfo *
1.400 djm 391: resolve_canonicalize(char **hostp, int port)
1.385 djm 392: {
1.443 djm 393: int i, direct, ndots;
1.413 djm 394: char *cp, *fullhost, newname[NI_MAXHOST];
1.385 djm 395: struct addrinfo *addrs;
396:
397: /*
1.470 djm 398: * Attempt to canonicalise addresses, regardless of
399: * whether hostname canonicalisation was requested
1.385 djm 400: */
1.413 djm 401: if ((addrs = resolve_addr(*hostp, port,
402: newname, sizeof(newname))) != NULL) {
403: debug2("%s: hostname %.100s is address", __func__, *hostp);
404: if (strcasecmp(*hostp, newname) != 0) {
405: debug2("%s: canonicalised address \"%s\" => \"%s\"",
406: __func__, *hostp, newname);
407: free(*hostp);
408: *hostp = xstrdup(newname);
409: }
410: return addrs;
411: }
412:
1.470 djm 413: /*
414: * If this looks like an address but didn't parse as one, it might
415: * be an address with an invalid interface scope. Skip further
416: * attempts at canonicalisation.
417: */
418: if (is_addr_fast(*hostp)) {
419: debug("%s: hostname %.100s is an unrecognised address",
420: __func__, *hostp);
421: return NULL;
422: }
423:
424: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
425: return NULL;
426:
427: /*
428: * Don't attempt to canonicalize names that will be interpreted by
429: * a proxy unless the user specifically requests so.
430: */
431: direct = option_clear_or_none(options.proxy_command) &&
432: options.jump_host == NULL;
433: if (!direct &&
434: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
435: return NULL;
436:
1.428 djm 437: /* If domain name is anchored, then resolve it now */
438: if ((*hostp)[strlen(*hostp) - 1] == '.') {
439: debug3("%s: name is fully qualified", __func__);
440: fullhost = xstrdup(*hostp);
441: if ((addrs = resolve_host(fullhost, port, 0,
442: newname, sizeof(newname))) != NULL)
443: goto found;
444: free(fullhost);
445: goto notfound;
446: }
447:
1.387 djm 448: /* Don't apply canonicalization to sufficiently-qualified hostnames */
1.385 djm 449: ndots = 0;
450: for (cp = *hostp; *cp != '\0'; cp++) {
451: if (*cp == '.')
452: ndots++;
453: }
1.386 djm 454: if (ndots > options.canonicalize_max_dots) {
455: debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)",
456: __func__, *hostp, options.canonicalize_max_dots);
1.385 djm 457: return NULL;
458: }
459: /* Attempt each supplied suffix */
460: for (i = 0; i < options.num_canonical_domains; i++) {
1.413 djm 461: *newname = '\0';
1.385 djm 462: xasprintf(&fullhost, "%s.%s.", *hostp,
463: options.canonical_domains[i]);
1.400 djm 464: debug3("%s: attempting \"%s\" => \"%s\"", __func__,
465: *hostp, fullhost);
466: if ((addrs = resolve_host(fullhost, port, 0,
1.413 djm 467: newname, sizeof(newname))) == NULL) {
1.385 djm 468: free(fullhost);
469: continue;
470: }
1.428 djm 471: found:
1.385 djm 472: /* Remove trailing '.' */
473: fullhost[strlen(fullhost) - 1] = '\0';
474: /* Follow CNAME if requested */
1.443 djm 475: if (!check_follow_cname(direct, &fullhost, newname)) {
1.386 djm 476: debug("Canonicalized hostname \"%s\" => \"%s\"",
1.385 djm 477: *hostp, fullhost);
478: }
479: free(*hostp);
480: *hostp = fullhost;
481: return addrs;
482: }
1.428 djm 483: notfound:
1.386 djm 484: if (!options.canonicalize_fallback_local)
1.400 djm 485: fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
486: debug2("%s: host %s not found in any suffix", __func__, *hostp);
1.385 djm 487: return NULL;
488: }
489:
1.32 deraadt 490: /*
1.483 markus 491: * Check the result of hostkey loading, ignoring some errors and
492: * fatal()ing for others.
493: */
494: static void
495: check_load(int r, const char *path, const char *message)
496: {
497: switch (r) {
498: case 0:
499: break;
500: case SSH_ERR_INTERNAL_ERROR:
501: case SSH_ERR_ALLOC_FAIL:
502: fatal("load %s \"%s\": %s", message, path, ssh_err(r));
503: case SSH_ERR_SYSTEM_ERROR:
504: /* Ignore missing files */
505: if (errno == ENOENT)
506: break;
507: /* FALLTHROUGH */
508: default:
509: error("load %s \"%s\": %s", message, path, ssh_err(r));
510: break;
511: }
512: }
513:
514: /*
1.400 djm 515: * Read per-user configuration file. Ignore the system wide config
516: * file if the user specifies a config file on the command line.
517: */
518: static void
1.466 djm 519: process_config_files(const char *host_name, struct passwd *pw, int post_canon)
1.400 djm 520: {
1.414 deraadt 521: char buf[PATH_MAX];
1.400 djm 522: int r;
523:
524: if (config != NULL) {
525: if (strcasecmp(config, "none") != 0 &&
1.466 djm 526: !read_config_file(config, pw, host, host_name, &options,
1.408 djm 527: SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0)))
1.400 djm 528: fatal("Can't open user config file %.100s: "
529: "%.100s", config, strerror(errno));
530: } else {
531: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
532: _PATH_SSH_USER_CONFFILE);
533: if (r > 0 && (size_t)r < sizeof(buf))
1.466 djm 534: (void)read_config_file(buf, pw, host, host_name,
1.408 djm 535: &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
536: (post_canon ? SSHCONF_POSTCANON : 0));
1.400 djm 537:
538: /* Read systemwide configuration file after user config. */
1.408 djm 539: (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
1.466 djm 540: host, host_name, &options,
1.408 djm 541: post_canon ? SSHCONF_POSTCANON : 0);
542: }
543: }
544:
545: /* Rewrite the port number in an addrinfo list of addresses */
546: static void
547: set_addrinfo_port(struct addrinfo *addrs, int port)
548: {
549: struct addrinfo *addr;
550:
551: for (addr = addrs; addr != NULL; addr = addr->ai_next) {
552: switch (addr->ai_family) {
553: case AF_INET:
554: ((struct sockaddr_in *)addr->ai_addr)->
555: sin_port = htons(port);
556: break;
557: case AF_INET6:
558: ((struct sockaddr_in6 *)addr->ai_addr)->
559: sin6_port = htons(port);
560: break;
561: }
1.400 djm 562: }
563: }
564:
565: /*
1.32 deraadt 566: * Main program for the ssh client.
567: */
1.2 provos 568: int
569: main(int ac, char **av)
1.1 deraadt 570: {
1.437 djm 571: struct ssh *ssh = NULL;
1.462 djm 572: int i, r, opt, exit_status, use_syslog, direct, timeout_ms;
1.470 djm 573: int was_addr, config_test = 0, opt_terminated = 0;
1.466 djm 574: char *p, *cp, *line, *argv0, buf[PATH_MAX], *logfile;
575: char cname[NI_MAXHOST];
1.31 markus 576: struct stat st;
1.98 markus 577: struct passwd *pw;
1.144 stevesk 578: extern int optind, optreset;
579: extern char *optarg;
1.406 millert 580: struct Forward fwd;
1.385 djm 581: struct addrinfo *addrs = NULL;
1.405 djm 582: struct ssh_digest_ctx *md;
583: u_char conn_hash[SSH_DIGEST_MAX_LENGTH];
1.250 djm 584:
1.436 dtucker 585: ssh_malloc_init(); /* must be called before any mallocs */
1.250 djm 586: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
587: sanitise_stdfd();
1.31 markus 588:
1.33 markus 589: /*
1.346 djm 590: * Discard other fds that are hanging around. These can cause problem
591: * with backgrounded ssh processes started by ControlPersist.
592: */
593: closefrom(STDERR_FILENO + 1);
594:
595: /*
1.33 markus 596: * Save the original real uid. It will be needed later (uid-swapping
597: * may clobber the real uid).
598: */
1.31 markus 599: original_real_uid = getuid();
600: original_effective_uid = geteuid();
601:
1.184 stevesk 602: /*
603: * Use uid-swapping to give up root privileges for the duration of
604: * option processing. We will re-instantiate the rights when we are
605: * ready to create the privileged port, and will permanently drop
606: * them when the port has been created (actually, when the connection
607: * has been made, as we may need to create the port several times).
608: */
609: PRIV_END;
610:
1.31 markus 611: /* If we are installed setuid root be careful to not drop core. */
612: if (original_real_uid != original_effective_uid) {
613: struct rlimit rlim;
614: rlim.rlim_cur = rlim.rlim_max = 0;
615: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
616: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 617: }
1.107 markus 618: /* Get user data. */
619: pw = getpwuid(original_real_uid);
620: if (!pw) {
1.380 djm 621: logit("No user exists for uid %lu", (u_long)original_real_uid);
1.257 dtucker 622: exit(255);
1.107 markus 623: }
624: /* Take a copy of the returned structure. */
625: pw = pwcopy(pw);
1.31 markus 626:
1.33 markus 627: /*
628: * Set our umask to something reasonable, as some files are created
629: * with the default umask. This will make them world-readable but
630: * writable only by the owner, which is ok for all files for which we
631: * don't set the modes explicitly.
632: */
1.31 markus 633: umask(022);
1.445 djm 634:
635: setlocale(LC_CTYPE, "");
1.31 markus 636:
1.316 djm 637: /*
638: * Initialize option structure to indicate that no values have been
639: * set.
640: */
1.31 markus 641: initialize_options(&options);
642:
1.463 djm 643: /*
644: * Prepare main ssh transport/connection structures
645: */
646: if ((ssh = ssh_alloc_session_state()) == NULL)
647: fatal("Couldn't allocate session state");
648: channel_init_channels(ssh);
649: active_state = ssh; /* XXX legacy API compat */
650:
1.31 markus 651: /* Parse command-line arguments. */
652: host = NULL;
1.320 djm 653: use_syslog = 0;
1.375 dtucker 654: logfile = NULL;
1.325 markus 655: argv0 = av[0];
1.31 markus 656:
1.266 djm 657: again:
1.316 djm 658: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.474 djm 659: "AB:CD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
1.31 markus 660: switch (opt) {
1.91 jakob 661: case '1':
1.454 djm 662: fatal("SSH protocol v.1 is no longer supported");
1.91 jakob 663: break;
1.47 markus 664: case '2':
1.454 djm 665: /* Ignored */
1.47 markus 666: break;
1.37 markus 667: case '4':
1.196 djm 668: options.address_family = AF_INET;
1.37 markus 669: break;
670: case '6':
1.196 djm 671: options.address_family = AF_INET6;
1.37 markus 672: break;
1.31 markus 673: case 'n':
674: stdin_null_flag = 1;
675: break;
676: case 'f':
677: fork_after_authentication_flag = 1;
678: stdin_null_flag = 1;
679: break;
680: case 'x':
681: options.forward_x11 = 0;
682: break;
683: case 'X':
684: options.forward_x11 = 1;
685: break;
1.320 djm 686: case 'y':
687: use_syslog = 1;
688: break;
1.375 dtucker 689: case 'E':
1.422 dtucker 690: logfile = optarg;
1.375 dtucker 691: break;
1.408 djm 692: case 'G':
693: config_test = 1;
694: break;
1.202 markus 695: case 'Y':
696: options.forward_x11 = 1;
697: options.forward_x11_trusted = 1;
698: break;
1.31 markus 699: case 'g':
1.406 millert 700: options.fwd_opts.gateway_ports = 1;
1.31 markus 701: break;
1.229 djm 702: case 'O':
1.441 dtucker 703: if (options.stdio_forward_host != NULL)
1.332 djm 704: fatal("Cannot specify multiplexing "
705: "command with -W");
706: else if (muxclient_command != 0)
707: fatal("Multiplexing command already specified");
1.229 djm 708: if (strcmp(optarg, "check") == 0)
1.312 djm 709: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 710: else if (strcmp(optarg, "forward") == 0)
711: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 712: else if (strcmp(optarg, "exit") == 0)
1.312 djm 713: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 714: else if (strcmp(optarg, "stop") == 0)
715: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 716: else if (strcmp(optarg, "cancel") == 0)
717: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.447 markus 718: else if (strcmp(optarg, "proxy") == 0)
719: muxclient_command = SSHMUX_COMMAND_PROXY;
1.229 djm 720: else
721: fatal("Invalid multiplex command.");
722: break;
1.183 stevesk 723: case 'P': /* deprecated */
1.31 markus 724: options.use_privileged_port = 0;
1.376 djm 725: break;
1.394 deraadt 726: case 'Q':
1.376 djm 727: cp = NULL;
1.394 deraadt 728: if (strcmp(optarg, "cipher") == 0)
1.393 djm 729: cp = cipher_alg_list('\n', 0);
1.394 deraadt 730: else if (strcmp(optarg, "cipher-auth") == 0)
1.393 djm 731: cp = cipher_alg_list('\n', 1);
1.394 deraadt 732: else if (strcmp(optarg, "mac") == 0)
1.392 dtucker 733: cp = mac_alg_list('\n');
1.394 deraadt 734: else if (strcmp(optarg, "kex") == 0)
1.392 dtucker 735: cp = kex_alg_list('\n');
1.394 deraadt 736: else if (strcmp(optarg, "key") == 0)
1.451 djm 737: cp = sshkey_alg_list(0, 0, 0, '\n');
1.396 markus 738: else if (strcmp(optarg, "key-cert") == 0)
1.451 djm 739: cp = sshkey_alg_list(1, 0, 0, '\n');
1.396 markus 740: else if (strcmp(optarg, "key-plain") == 0)
1.451 djm 741: cp = sshkey_alg_list(0, 1, 0, '\n');
1.416 djm 742: else if (strcmp(optarg, "protocol-version") == 0) {
743: cp = xstrdup("2");
744: }
1.376 djm 745: if (cp == NULL)
746: fatal("Unsupported query \"%s\"", optarg);
747: printf("%s\n", cp);
748: free(cp);
749: exit(0);
1.31 markus 750: break;
751: case 'a':
752: options.forward_agent = 0;
1.53 markus 753: break;
754: case 'A':
755: options.forward_agent = 1;
1.31 markus 756: break;
757: case 'k':
1.204 dtucker 758: options.gss_deleg_creds = 0;
1.297 djm 759: break;
760: case 'K':
761: options.gss_authentication = 1;
762: options.gss_deleg_creds = 1;
1.31 markus 763: break;
764: case 'i':
1.429 dtucker 765: p = tilde_expand_filename(optarg, original_real_uid);
766: if (stat(p, &st) < 0)
1.128 fgsch 767: fprintf(stderr, "Warning: Identity file %s "
1.429 dtucker 768: "not accessible: %s.\n", p,
1.231 otto 769: strerror(errno));
1.429 dtucker 770: else
771: add_identity_file(&options, NULL, p, 1);
772: free(p);
1.31 markus 773: break;
1.127 markus 774: case 'I':
1.333 markus 775: #ifdef ENABLE_PKCS11
1.422 dtucker 776: free(options.pkcs11_provider);
1.333 markus 777: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 778: #else
1.333 markus 779: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 780: #endif
1.127 markus 781: break;
1.443 djm 782: case 'J':
783: if (options.jump_host != NULL)
784: fatal("Only a single -J option permitted");
785: if (options.proxy_command != NULL)
786: fatal("Cannot specify -J with ProxyCommand");
787: if (parse_jump(optarg, &options, 1) == -1)
788: fatal("Invalid -J argument");
789: options.proxy_command = xstrdup("none");
790: break;
1.31 markus 791: case 't':
1.359 djm 792: if (options.request_tty == REQUEST_TTY_YES)
793: options.request_tty = REQUEST_TTY_FORCE;
794: else
795: options.request_tty = REQUEST_TTY_YES;
1.31 markus 796: break;
797: case 'v':
1.197 markus 798: if (debug_flag == 0) {
1.66 markus 799: debug_flag = 1;
800: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 801: } else {
1.443 djm 802: if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
803: debug_flag++;
1.197 markus 804: options.log_level++;
1.443 djm 805: }
1.197 markus 806: }
1.375 dtucker 807: break;
1.31 markus 808: case 'V':
1.209 markus 809: fprintf(stderr, "%s, %s\n",
1.402 markus 810: SSH_VERSION,
811: #ifdef WITH_OPENSSL
812: SSLeay_version(SSLEAY_VERSION)
813: #else
814: "without OpenSSL"
815: #endif
816: );
1.31 markus 817: if (opt == 'V')
818: exit(0);
819: break;
1.255 reyk 820: case 'w':
1.256 reyk 821: if (options.tun_open == -1)
822: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 823: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 824: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 825: fprintf(stderr,
826: "Bad tun device '%s'\n", optarg);
1.257 dtucker 827: exit(255);
1.255 reyk 828: }
829: break;
1.331 dtucker 830: case 'W':
1.441 dtucker 831: if (options.stdio_forward_host != NULL)
1.332 djm 832: fatal("stdio forward already specified");
833: if (muxclient_command != 0)
834: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 835: if (parse_forward(&fwd, optarg, 1, 0)) {
1.441 dtucker 836: options.stdio_forward_host = fwd.listen_host;
837: options.stdio_forward_port = fwd.listen_port;
1.378 djm 838: free(fwd.connect_host);
1.331 dtucker 839: } else {
840: fprintf(stderr,
841: "Bad stdio forwarding specification '%s'\n",
842: optarg);
843: exit(255);
844: }
1.359 djm 845: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 846: no_shell_flag = 1;
847: break;
1.31 markus 848: case 'q':
849: options.log_level = SYSLOG_LEVEL_QUIET;
850: break;
851: case 'e':
852: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 853: (u_char) optarg[1] >= 64 &&
854: (u_char) optarg[1] < 128)
1.78 markus 855: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 856: else if (strlen(optarg) == 1)
1.78 markus 857: options.escape_char = (u_char) optarg[0];
1.31 markus 858: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 859: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 860: else {
1.128 fgsch 861: fprintf(stderr, "Bad escape character '%s'.\n",
862: optarg);
1.257 dtucker 863: exit(255);
1.31 markus 864: }
865: break;
866: case 'c':
1.456 djm 867: if (!ciphers_valid(*optarg == '+' ?
1.420 djm 868: optarg + 1 : optarg)) {
869: fprintf(stderr, "Unknown cipher type '%s'\n",
870: optarg);
871: exit(255);
1.95 markus 872: }
1.456 djm 873: free(options.ciphers);
874: options.ciphers = xstrdup(optarg);
1.95 markus 875: break;
876: case 'm':
1.422 dtucker 877: if (mac_valid(optarg)) {
878: free(options.macs);
1.95 markus 879: options.macs = xstrdup(optarg);
1.422 dtucker 880: } else {
1.128 fgsch 881: fprintf(stderr, "Unknown mac type '%s'\n",
882: optarg);
1.257 dtucker 883: exit(255);
1.31 markus 884: }
885: break;
1.214 djm 886: case 'M':
1.242 djm 887: if (options.control_master == SSHCTL_MASTER_YES)
888: options.control_master = SSHCTL_MASTER_ASK;
889: else
890: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 891: break;
1.31 markus 892: case 'p':
1.465 millert 893: if (options.port == -1) {
894: options.port = a2port(optarg);
895: if (options.port <= 0) {
896: fprintf(stderr, "Bad port '%s'\n",
897: optarg);
898: exit(255);
899: }
1.109 markus 900: }
1.31 markus 901: break;
902: case 'l':
1.465 millert 903: if (options.user == NULL)
904: options.user = optarg;
1.31 markus 905: break;
1.141 stevesk 906:
907: case 'L':
1.324 djm 908: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 909: add_local_forward(&options, &fwd);
910: else {
1.128 fgsch 911: fprintf(stderr,
1.232 djm 912: "Bad local forwarding specification '%s'\n",
1.128 fgsch 913: optarg);
1.257 dtucker 914: exit(255);
1.31 markus 915: }
1.232 djm 916: break;
917:
918: case 'R':
1.464 markus 919: if (parse_forward(&fwd, optarg, 0, 1) ||
920: parse_forward(&fwd, optarg, 1, 1)) {
1.232 djm 921: add_remote_forward(&options, &fwd);
922: } else {
1.128 fgsch 923: fprintf(stderr,
1.232 djm 924: "Bad remote forwarding specification "
925: "'%s'\n", optarg);
1.257 dtucker 926: exit(255);
1.31 markus 927: }
928: break;
1.108 markus 929:
930: case 'D':
1.324 djm 931: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 932: add_local_forward(&options, &fwd);
1.232 djm 933: } else {
1.322 stevesk 934: fprintf(stderr,
935: "Bad dynamic forwarding specification "
936: "'%s'\n", optarg);
1.257 dtucker 937: exit(255);
1.109 markus 938: }
1.108 markus 939: break;
940:
1.31 markus 941: case 'C':
942: options.compression = 1;
943: break;
1.45 markus 944: case 'N':
945: no_shell_flag = 1;
1.359 djm 946: options.request_tty = REQUEST_TTY_NO;
1.45 markus 947: break;
948: case 'T':
1.359 djm 949: options.request_tty = REQUEST_TTY_NO;
1.45 markus 950: break;
1.31 markus 951: case 'o':
1.205 markus 952: line = xstrdup(optarg);
1.408 djm 953: if (process_config_line(&options, pw,
954: host ? host : "", host ? host : "", line,
955: "command-line", 0, NULL, SSHCONF_USERCONF) != 0)
1.257 dtucker 956: exit(255);
1.378 djm 957: free(line);
1.31 markus 958: break;
1.85 djm 959: case 's':
960: subsystem_flag = 1;
1.117 markus 961: break;
1.214 djm 962: case 'S':
1.431 mmcc 963: free(options.control_path);
1.214 djm 964: options.control_path = xstrdup(optarg);
965: break;
1.117 markus 966: case 'b':
967: options.bind_address = optarg;
1.474 djm 968: break;
969: case 'B':
970: options.bind_interface = optarg;
1.85 djm 971: break;
1.139 markus 972: case 'F':
973: config = optarg;
974: break;
1.31 markus 975: default:
976: usage();
1.1 deraadt 977: }
1.31 markus 978: }
979:
1.462 djm 980: if (optind > 1 && strcmp(av[optind - 1], "--") == 0)
981: opt_terminated = 1;
982:
1.128 fgsch 983: ac -= optind;
984: av += optind;
985:
1.329 guenther 986: if (ac > 0 && !host) {
1.465 millert 987: int tport;
988: char *tuser;
989: switch (parse_ssh_uri(*av, &tuser, &host, &tport)) {
990: case -1:
991: usage();
992: break;
993: case 0:
994: if (options.user == NULL) {
995: options.user = tuser;
996: tuser = NULL;
997: }
998: free(tuser);
999: if (options.port == -1 && tport != -1)
1000: options.port = tport;
1001: break;
1002: default:
1.128 fgsch 1003: p = xstrdup(*av);
1.188 markus 1004: cp = strrchr(p, '@');
1.465 millert 1005: if (cp != NULL) {
1006: if (cp == p)
1007: usage();
1008: if (options.user == NULL) {
1009: options.user = p;
1010: p = NULL;
1011: }
1012: *cp++ = '\0';
1013: host = xstrdup(cp);
1014: free(p);
1015: } else
1016: host = p;
1017: break;
1018: }
1.462 djm 1019: if (ac > 1 && !opt_terminated) {
1.189 millert 1020: optind = optreset = 1;
1.128 fgsch 1021: goto again;
1022: }
1.189 millert 1023: ac--, av++;
1.128 fgsch 1024: }
1025:
1.31 markus 1026: /* Check that we got a host name. */
1027: if (!host)
1028: usage();
1029:
1.385 djm 1030: host_arg = xstrdup(host);
1031:
1.402 markus 1032: #ifdef WITH_OPENSSL
1.350 djm 1033: OpenSSL_add_all_algorithms();
1.72 markus 1034: ERR_load_crypto_strings();
1.402 markus 1035: #endif
1.31 markus 1036:
1037: /* Initialize the command to execute on remote host. */
1.482 markus 1038: if ((command = sshbuf_new()) == NULL)
1039: fatal("sshbuf_new failed");
1.1 deraadt 1040:
1.33 markus 1041: /*
1042: * Save the command to execute on the remote host in a buffer. There
1043: * is no limit on the length of the command, except by the maximum
1044: * packet size. Also sets the tty flag if there is no command.
1045: */
1.128 fgsch 1046: if (!ac) {
1.31 markus 1047: /* No command specified - execute shell on a tty. */
1.85 djm 1048: if (subsystem_flag) {
1.128 fgsch 1049: fprintf(stderr,
1050: "You must specify a subsystem to invoke.\n");
1.85 djm 1051: usage();
1052: }
1.31 markus 1053: } else {
1.128 fgsch 1054: /* A command has been specified. Store it into the buffer. */
1055: for (i = 0; i < ac; i++) {
1.482 markus 1056: if ((r = sshbuf_putf(command, "%s%s",
1057: i ? " " : "", av[i])) != 0)
1058: fatal("%s: buffer error: %s",
1059: __func__, ssh_err(r));
1.31 markus 1060: }
1061: }
1062:
1.101 markus 1063: /*
1064: * Initialize "log" output. Since we are the client all output
1.375 dtucker 1065: * goes to stderr unless otherwise specified by -y or -E.
1.101 markus 1066: */
1.375 dtucker 1067: if (use_syslog && logfile != NULL)
1068: fatal("Can't specify both -y and -E");
1.422 dtucker 1069: if (logfile != NULL)
1.375 dtucker 1070: log_redirect_stderr_to(logfile);
1.325 markus 1071: log_init(argv0,
1.468 djm 1072: options.log_level == SYSLOG_LEVEL_NOT_SET ?
1.452 dtucker 1073: SYSLOG_LEVEL_INFO : options.log_level,
1.468 djm 1074: options.log_facility == SYSLOG_FACILITY_NOT_SET ?
1.452 dtucker 1075: SYSLOG_FACILITY_USER : options.log_facility,
1076: !use_syslog);
1.375 dtucker 1077:
1078: if (debug_flag)
1.402 markus 1079: logit("%s, %s", SSH_VERSION,
1080: #ifdef WITH_OPENSSL
1081: SSLeay_version(SSLEAY_VERSION)
1082: #else
1083: "without OpenSSL"
1084: #endif
1085: );
1.31 markus 1086:
1.400 djm 1087: /* Parse the configuration files */
1.408 djm 1088: process_config_files(host_arg, pw, 0);
1.400 djm 1089:
1090: /* Hostname canonicalisation needs a few options filled. */
1091: fill_default_options_for_canonicalization(&options);
1092:
1093: /* If the user has replaced the hostname then take it into use now */
1094: if (options.hostname != NULL) {
1095: /* NB. Please keep in sync with readconf.c:match_cfg_line() */
1096: cp = percent_expand(options.hostname,
1097: "h", host, (char *)NULL);
1098: free(host);
1099: host = cp;
1.408 djm 1100: free(options.hostname);
1101: options.hostname = xstrdup(host);
1.400 djm 1102: }
1103:
1.470 djm 1104: /* Don't lowercase addresses, they will be explicitly canonicalised */
1105: if ((was_addr = is_addr(host)) == 0)
1106: lowercase(host);
1107:
1108: /*
1109: * Try to canonicalize if requested by configuration or the
1110: * hostname is an address.
1111: */
1112: if (options.canonicalize_hostname != SSH_CANONICALISE_NO || was_addr)
1.400 djm 1113: addrs = resolve_canonicalize(&host, options.port);
1114:
1.139 markus 1115: /*
1.401 djm 1116: * If CanonicalizePermittedCNAMEs have been specified but
1117: * other canonicalization did not happen (by not being requested
1118: * or by failing with fallback) then the hostname may still be changed
1.468 djm 1119: * as a result of CNAME following.
1.401 djm 1120: *
1121: * Try to resolve the bare hostname name using the system resolver's
1122: * usual search rules and then apply the CNAME follow rules.
1123: *
1124: * Skip the lookup if a ProxyCommand is being used unless the user
1125: * has specifically requested canonicalisation for this case via
1126: * CanonicalizeHostname=always
1.139 markus 1127: */
1.443 djm 1128: direct = option_clear_or_none(options.proxy_command) &&
1129: options.jump_host == NULL;
1130: if (addrs == NULL && options.num_permitted_cnames != 0 && (direct ||
1131: options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
1.403 djm 1132: if ((addrs = resolve_host(host, options.port,
1133: option_clear_or_none(options.proxy_command),
1134: cname, sizeof(cname))) == NULL) {
1135: /* Don't fatal proxied host names not in the DNS */
1136: if (option_clear_or_none(options.proxy_command))
1137: cleanup_exit(255); /* logged in resolve_host */
1138: } else
1.443 djm 1139: check_follow_cname(direct, &host, cname);
1.400 djm 1140: }
1.139 markus 1141:
1.400 djm 1142: /*
1.408 djm 1143: * If canonicalisation is enabled then re-parse the configuration
1144: * files as new stanzas may match.
1.400 djm 1145: */
1.408 djm 1146: if (options.canonicalize_hostname != 0) {
1147: debug("Re-reading configuration after hostname "
1148: "canonicalisation");
1149: free(options.hostname);
1150: options.hostname = xstrdup(host);
1151: process_config_files(host_arg, pw, 1);
1152: /*
1153: * Address resolution happens early with canonicalisation
1154: * enabled and the port number may have changed since, so
1155: * reset it in address list
1156: */
1157: if (addrs != NULL && options.port > 0)
1158: set_addrinfo_port(addrs, options.port);
1.139 markus 1159: }
1.31 markus 1160:
1161: /* Fill configuration defaults. */
1162: fill_default_options(&options);
1.443 djm 1163:
1164: /*
1165: * If ProxyJump option specified, then construct a ProxyCommand now.
1166: */
1167: if (options.jump_host != NULL) {
1168: char port_s[8];
1.478 djm 1169: const char *sshbin = argv0;
1170:
1171: /*
1172: * Try to use SSH indicated by argv[0], but fall back to
1173: * "ssh" if it appears unavailable.
1174: */
1175: if (strchr(argv0, '/') != NULL && access(argv0, X_OK) != 0)
1176: sshbin = "ssh";
1.443 djm 1177:
1178: /* Consistency check */
1179: if (options.proxy_command != NULL)
1180: fatal("inconsistent options: ProxyCommand+ProxyJump");
1181: /* Never use FD passing for ProxyJump */
1182: options.proxy_use_fdpass = 0;
1183: snprintf(port_s, sizeof(port_s), "%d", options.jump_port);
1184: xasprintf(&options.proxy_command,
1.478 djm 1185: "%s%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s",
1186: sshbin,
1.443 djm 1187: /* Optional "-l user" argument if jump_user set */
1188: options.jump_user == NULL ? "" : " -l ",
1189: options.jump_user == NULL ? "" : options.jump_user,
1190: /* Optional "-p port" argument if jump_port set */
1191: options.jump_port <= 0 ? "" : " -p ",
1192: options.jump_port <= 0 ? "" : port_s,
1193: /* Optional additional jump hosts ",..." */
1194: options.jump_extra == NULL ? "" : " -J ",
1195: options.jump_extra == NULL ? "" : options.jump_extra,
1196: /* Optional "-F" argumment if -F specified */
1197: config == NULL ? "" : " -F ",
1198: config == NULL ? "" : config,
1199: /* Optional "-v" arguments if -v set */
1200: debug_flag ? " -" : "",
1201: debug_flag, "vvv",
1202: /* Mandatory hostname */
1203: options.jump_host);
1204: debug("Setting implicit ProxyCommand from ProxyJump: %s",
1205: options.proxy_command);
1206: }
1.31 markus 1207:
1.400 djm 1208: if (options.port == 0)
1209: options.port = default_ssh_port();
1.463 djm 1210: channel_set_af(ssh, options.address_family);
1.196 djm 1211:
1.383 djm 1212: /* Tidy and check options */
1213: if (options.host_key_alias != NULL)
1214: lowercase(options.host_key_alias);
1215: if (options.proxy_command != NULL &&
1216: strcmp(options.proxy_command, "-") == 0 &&
1217: options.proxy_use_fdpass)
1218: fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
1.415 djm 1219: if (options.control_persist &&
1220: options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1221: debug("UpdateHostKeys=ask is incompatible with ControlPersist; "
1222: "disabling");
1223: options.update_hostkeys = 0;
1224: }
1.430 djm 1225: if (options.connection_attempts <= 0)
1226: fatal("Invalid number of ConnectionAttempts");
1227:
1.388 djm 1228: if (original_effective_uid != 0)
1229: options.use_privileged_port = 0;
1.383 djm 1230:
1.482 markus 1231: if (sshbuf_len(command) != 0 && options.remote_command != NULL)
1.461 bluhm 1232: fatal("Cannot execute command-line and remote command.");
1233:
1234: /* Cannot fork to background if no command. */
1.482 markus 1235: if (fork_after_authentication_flag && sshbuf_len(command) == 0 &&
1.461 bluhm 1236: options.remote_command == NULL && !no_shell_flag)
1237: fatal("Cannot fork into background without a command "
1238: "to execute.");
1239:
1.31 markus 1240: /* reinit */
1.452 dtucker 1241: log_init(argv0, options.log_level, options.log_facility, !use_syslog);
1.370 djm 1242:
1243: if (options.request_tty == REQUEST_TTY_YES ||
1244: options.request_tty == REQUEST_TTY_FORCE)
1245: tty_flag = 1;
1246:
1247: /* Allocate a tty by default if no command specified. */
1.482 markus 1248: if (sshbuf_len(command) == 0 && options.remote_command == NULL)
1.370 djm 1249: tty_flag = options.request_tty != REQUEST_TTY_NO;
1250:
1251: /* Force no tty */
1.447 markus 1252: if (options.request_tty == REQUEST_TTY_NO ||
1253: (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY))
1.370 djm 1254: tty_flag = 0;
1255: /* Do not allocate a tty if stdin is not a tty. */
1256: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
1257: options.request_tty != REQUEST_TTY_FORCE) {
1258: if (tty_flag)
1259: logit("Pseudo-terminal will not be allocated because "
1260: "stdin is not a terminal.");
1261: tty_flag = 0;
1262: }
1.31 markus 1263:
1264: if (options.user == NULL)
1265: options.user = xstrdup(pw->pw_name);
1.343 djm 1266:
1.466 djm 1267: /* Set up strings used to percent_expand() arguments */
1.358 djm 1268: if (gethostname(thishost, sizeof(thishost)) == -1)
1269: fatal("gethostname: %s", strerror(errno));
1270: strlcpy(shorthost, thishost, sizeof(shorthost));
1271: shorthost[strcspn(thishost, ".")] = '\0';
1272: snprintf(portstr, sizeof(portstr), "%d", options.port);
1.479 djm 1273: snprintf(uidstr, sizeof(uidstr), "%llu",
1274: (unsigned long long)pw->pw_uid);
1.358 djm 1275:
1.405 djm 1276: if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL ||
1277: ssh_digest_update(md, thishost, strlen(thishost)) < 0 ||
1278: ssh_digest_update(md, host, strlen(host)) < 0 ||
1279: ssh_digest_update(md, portstr, strlen(portstr)) < 0 ||
1280: ssh_digest_update(md, options.user, strlen(options.user)) < 0 ||
1281: ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0)
1282: fatal("%s: mux digest failed", __func__);
1283: ssh_digest_free(md);
1284: conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
1285:
1.466 djm 1286: /*
1287: * Expand tokens in arguments. NB. LocalCommand is expanded later,
1288: * after port-forwarding is set up, so it may pick up any local
1289: * tunnel interface name allocated.
1290: */
1.461 bluhm 1291: if (options.remote_command != NULL) {
1292: debug3("expanding RemoteCommand: %s", options.remote_command);
1293: cp = options.remote_command;
1294: options.remote_command = percent_expand(cp,
1295: "C", conn_hash_hex,
1296: "L", shorthost,
1297: "d", pw->pw_dir,
1298: "h", host,
1.479 djm 1299: "i", uidstr,
1.461 bluhm 1300: "l", thishost,
1301: "n", host_arg,
1302: "p", portstr,
1303: "r", options.user,
1304: "u", pw->pw_name,
1305: (char *)NULL);
1306: debug3("expanded RemoteCommand: %s", options.remote_command);
1307: free(cp);
1.482 markus 1308: if ((r = sshbuf_put(command, options.remote_command,
1309: strlen(options.remote_command))) != 0)
1310: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.304 dtucker 1311: }
1.31 markus 1312:
1.214 djm 1313: if (options.control_path != NULL) {
1.241 djm 1314: cp = tilde_expand_filename(options.control_path,
1315: original_real_uid);
1.378 djm 1316: free(options.control_path);
1.405 djm 1317: options.control_path = percent_expand(cp,
1318: "C", conn_hash_hex,
1319: "L", shorthost,
1320: "h", host,
1.479 djm 1321: "i", uidstr,
1.405 djm 1322: "l", thishost,
1323: "n", host_arg,
1324: "p", portstr,
1325: "r", options.user,
1326: "u", pw->pw_name,
1.423 djm 1327: "i", uidstr,
1.358 djm 1328: (char *)NULL);
1.378 djm 1329: free(cp);
1.214 djm 1330: }
1.408 djm 1331:
1332: if (config_test) {
1333: dump_client_config(&options, host);
1334: exit(0);
1335: }
1.405 djm 1336:
1.312 djm 1337: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 1338: fatal("No ControlPath specified for \"-O\" command");
1.447 markus 1339: if (options.control_path != NULL) {
1340: int sock;
1341: if ((sock = muxclient(options.control_path)) >= 0) {
1.463 djm 1342: ssh_packet_set_connection(ssh, sock, sock);
1.447 markus 1343: packet_set_mux();
1344: goto skip_connect;
1345: }
1346: }
1.401 djm 1347:
1348: /*
1349: * If hostname canonicalisation was not enabled, then we may not
1350: * have yet resolved the hostname. Do so now.
1351: */
1352: if (addrs == NULL && options.proxy_command == NULL) {
1.421 djm 1353: debug2("resolving \"%s\" port %d", host, options.port);
1.401 djm 1354: if ((addrs = resolve_host(host, options.port, 1,
1355: cname, sizeof(cname))) == NULL)
1356: cleanup_exit(255); /* resolve_host logs the error */
1357: }
1.214 djm 1358:
1.303 djm 1359: timeout_ms = options.connection_timeout * 1000;
1360:
1.77 markus 1361: /* Open a connection to the remote host. */
1.463 djm 1362: if (ssh_connect(ssh, host, addrs, &hostaddr, options.port,
1.385 djm 1363: options.address_family, options.connection_attempts,
1364: &timeout_ms, options.tcp_keep_alive,
1.388 djm 1365: options.use_privileged_port) != 0)
1.257 dtucker 1366: exit(255);
1.31 markus 1367:
1.391 djm 1368: if (addrs != NULL)
1369: freeaddrinfo(addrs);
1370:
1.385 djm 1371: packet_set_timeout(options.server_alive_interval,
1372: options.server_alive_count_max);
1373:
1.437 djm 1374: ssh = active_state; /* XXX */
1375:
1.303 djm 1376: if (timeout_ms > 0)
1377: debug3("timeout: %d ms remain after connect", timeout_ms);
1378:
1.33 markus 1379: /*
1.485 dtucker 1380: * If we successfully made the connection and we have hostbased auth
1381: * enabled, load the public keys so we can later use the ssh-keysign
1382: * helper to sign challenges.
1.33 markus 1383: */
1.112 markus 1384: sensitive_data.nkeys = 0;
1385: sensitive_data.keys = NULL;
1.457 djm 1386: if (options.hostbased_authentication) {
1.486 ! dtucker 1387: sensitive_data.nkeys = 10;
1.274 deraadt 1388: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.483 markus 1389: sizeof(struct sshkey));
1390:
1391: /* XXX check errors? */
1.486 ! dtucker 1392: #define L_PUBKEY(p,o) do { \
! 1393: if ((o) >= sensitive_data.nkeys) \
! 1394: fatal("%s pubkey out of array bounds", __func__); \
1.483 markus 1395: check_load(sshkey_load_public(p, &(sensitive_data.keys[o]), NULL), \
1.486 ! dtucker 1396: p, "pubkey"); \
! 1397: } while (0)
! 1398: #define L_CERT(p,o) do { \
! 1399: if ((o) >= sensitive_data.nkeys) \
! 1400: fatal("%s cert out of array bounds", __func__); \
! 1401: check_load(sshkey_load_cert(p, &(sensitive_data.keys[o])), p, "cert"); \
! 1402: } while (0)
1.177 markus 1403:
1.485 dtucker 1404: if (options.hostbased_authentication == 1) {
1.486 ! dtucker 1405: L_CERT(_PATH_HOST_ECDSA_KEY_FILE, 0);
! 1406: L_CERT(_PATH_HOST_ED25519_KEY_FILE, 1);
! 1407: L_CERT(_PATH_HOST_RSA_KEY_FILE, 2);
! 1408: L_CERT(_PATH_HOST_DSA_KEY_FILE, 3);
! 1409: L_PUBKEY(_PATH_HOST_ECDSA_KEY_FILE, 4);
! 1410: L_PUBKEY(_PATH_HOST_ED25519_KEY_FILE, 5);
! 1411: L_PUBKEY(_PATH_HOST_RSA_KEY_FILE, 6);
! 1412: L_PUBKEY(_PATH_HOST_DSA_KEY_FILE, 7);
! 1413: L_CERT(_PATH_HOST_XMSS_KEY_FILE, 8);
! 1414: L_PUBKEY(_PATH_HOST_XMSS_KEY_FILE, 9);
1.173 markus 1415: }
1.31 markus 1416: }
1.33 markus 1417: /*
1418: * Get rid of any extra privileges that we may have. We will no
1419: * longer need them. Also, extra privileges could make it very hard
1420: * to read identity files and other non-world-readable files from the
1421: * user's home directory if it happens to be on a NFS volume where
1422: * root is mapped to nobody.
1423: */
1.225 dtucker 1424: if (original_effective_uid == 0) {
1425: PRIV_START;
1426: permanently_set_uid(pw);
1427: }
1.31 markus 1428:
1.33 markus 1429: /*
1430: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 1431: * directory if it doesn't already exist.
1.33 markus 1432: */
1.367 djm 1433: if (config == NULL) {
1434: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1435: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1436: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
1437: if (mkdir(buf, 0700) < 0)
1438: error("Could not create directory '%.200s'.",
1439: buf);
1440: }
1.31 markus 1441:
1.104 markus 1442: /* load options.identity_files */
1.466 djm 1443: load_public_identity_files(pw);
1.439 markus 1444:
1.476 djm 1445: /* optionally set the SSH_AUTHSOCKET_ENV_NAME variable */
1.440 markus 1446: if (options.identity_agent &&
1447: strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) {
1.439 markus 1448: if (strcmp(options.identity_agent, "none") == 0) {
1449: unsetenv(SSH_AUTHSOCKET_ENV_NAME);
1450: } else {
1451: p = tilde_expand_filename(options.identity_agent,
1452: original_real_uid);
1.479 djm 1453: cp = percent_expand(p,
1454: "d", pw->pw_dir,
1455: "h", host,
1456: "i", uidstr,
1457: "l", thishost,
1458: "r", options.user,
1459: "u", pw->pw_name,
1460: (char *)NULL);
1.439 markus 1461: setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1);
1462: free(cp);
1463: free(p);
1464: }
1465: }
1.104 markus 1466:
1467: /* Expand ~ in known host file names. */
1.361 djm 1468: tilde_expand_paths(options.system_hostfiles,
1469: options.num_system_hostfiles);
1470: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 1471:
1472: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 1473: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 1474:
1.316 djm 1475: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 1476: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 1477: options.port, pw, timeout_ms);
1.339 djm 1478:
1479: if (packet_connection_is_on_socket()) {
1480: verbose("Authenticated to %s ([%s]:%d).", host,
1.437 djm 1481: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.339 djm 1482: } else {
1483: verbose("Authenticated to %s (via proxy).", host);
1484: }
1.31 markus 1485:
1.112 markus 1486: /* We no longer need the private host keys. Clear them now. */
1487: if (sensitive_data.nkeys != 0) {
1488: for (i = 0; i < sensitive_data.nkeys; i++) {
1489: if (sensitive_data.keys[i] != NULL) {
1490: /* Destroys contents safely */
1491: debug3("clear hostkey %d", i);
1.483 markus 1492: sshkey_free(sensitive_data.keys[i]);
1.112 markus 1493: sensitive_data.keys[i] = NULL;
1494: }
1495: }
1.378 djm 1496: free(sensitive_data.keys);
1.134 markus 1497: }
1498: for (i = 0; i < options.num_identity_files; i++) {
1.378 djm 1499: free(options.identity_files[i]);
1500: options.identity_files[i] = NULL;
1.134 markus 1501: if (options.identity_keys[i]) {
1.483 markus 1502: sshkey_free(options.identity_keys[i]);
1.134 markus 1503: options.identity_keys[i] = NULL;
1504: }
1.112 markus 1505: }
1.426 djm 1506: for (i = 0; i < options.num_certificate_files; i++) {
1507: free(options.certificate_files[i]);
1508: options.certificate_files[i] = NULL;
1509: }
1.31 markus 1510:
1.447 markus 1511: skip_connect:
1.466 djm 1512: exit_status = ssh_session2(ssh, pw);
1.45 markus 1513: packet_close();
1.186 djm 1514:
1.312 djm 1515: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 1516: unlink(options.control_path);
1517:
1.353 djm 1518: /* Kill ProxyCommand if it is running. */
1519: ssh_kill_proxy_command();
1.186 djm 1520:
1.45 markus 1521: return exit_status;
1522: }
1523:
1.344 djm 1524: static void
1525: control_persist_detach(void)
1526: {
1527: pid_t pid;
1.438 djm 1528: int devnull, keep_stderr;
1.344 djm 1529:
1530: debug("%s: backgrounding master process", __func__);
1531:
1.473 djm 1532: /*
1533: * master (current process) into the background, and make the
1534: * foreground process a client of the backgrounded master.
1535: */
1.344 djm 1536: switch ((pid = fork())) {
1537: case -1:
1538: fatal("%s: fork: %s", __func__, strerror(errno));
1539: case 0:
1540: /* Child: master process continues mainloop */
1.473 djm 1541: break;
1542: default:
1.344 djm 1543: /* Parent: set up mux slave to connect to backgrounded master */
1544: debug2("%s: background process is %ld", __func__, (long)pid);
1545: stdin_null_flag = ostdin_null_flag;
1.359 djm 1546: options.request_tty = orequest_tty;
1.344 djm 1547: tty_flag = otty_flag;
1.473 djm 1548: close(muxserver_sock);
1549: muxserver_sock = -1;
1.351 markus 1550: options.control_master = SSHCTL_MASTER_NO;
1.473 djm 1551: muxclient(options.control_path);
1.344 djm 1552: /* muxclient() doesn't return on success. */
1.473 djm 1553: fatal("Failed to connect to new control master");
1554: }
1.346 djm 1555: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1556: error("%s: open(\"/dev/null\"): %s", __func__,
1557: strerror(errno));
1558: } else {
1.438 djm 1559: keep_stderr = log_is_on_stderr() && debug_flag;
1.346 djm 1560: if (dup2(devnull, STDIN_FILENO) == -1 ||
1.438 djm 1561: dup2(devnull, STDOUT_FILENO) == -1 ||
1562: (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1))
1.346 djm 1563: error("%s: dup2: %s", __func__, strerror(errno));
1564: if (devnull > STDERR_FILENO)
1565: close(devnull);
1566: }
1.381 djm 1567: daemon(1, 1);
1.362 djm 1568: setproctitle("%s [mux]", options.control_path);
1.344 djm 1569: }
1570:
1571: /* Do fork() after authentication. Used by "ssh -f" */
1572: static void
1573: fork_postauth(void)
1574: {
1575: if (need_controlpersist_detach)
1576: control_persist_detach();
1577: debug("forking to background");
1578: fork_after_authentication_flag = 0;
1579: if (daemon(1, 1) < 0)
1580: fatal("daemon() failed: %.200s", strerror(errno));
1581: }
1582:
1.315 djm 1583: /* Callback for remote forward global requests */
1584: static void
1.463 djm 1585: ssh_confirm_remote_forward(struct ssh *ssh, int type, u_int32_t seq, void *ctxt)
1.315 djm 1586: {
1.406 millert 1587: struct Forward *rfwd = (struct Forward *)ctxt;
1.315 djm 1588:
1.324 djm 1589: /* XXX verbose() on failure? */
1.404 markus 1590: debug("remote forward %s for: listen %s%s%d, connect %s:%d",
1.315 djm 1591: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1.406 millert 1592: rfwd->listen_path ? rfwd->listen_path :
1593: rfwd->listen_host ? rfwd->listen_host : "",
1594: (rfwd->listen_path || rfwd->listen_host) ? ":" : "",
1595: rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
1596: rfwd->connect_host, rfwd->connect_port);
1597: if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
1.366 markus 1598: if (type == SSH2_MSG_REQUEST_SUCCESS) {
1599: rfwd->allocated_port = packet_get_int();
1600: logit("Allocated port %u for remote forward to %s:%d",
1601: rfwd->allocated_port,
1602: rfwd->connect_host, rfwd->connect_port);
1.480 djm 1603: channel_update_permission(ssh,
1.463 djm 1604: rfwd->handle, rfwd->allocated_port);
1.366 markus 1605: } else {
1.480 djm 1606: channel_update_permission(ssh, rfwd->handle, -1);
1.366 markus 1607: }
1.324 djm 1608: }
1.468 djm 1609:
1.315 djm 1610: if (type == SSH2_MSG_REQUEST_FAILURE) {
1.406 millert 1611: if (options.exit_on_forward_failure) {
1612: if (rfwd->listen_path != NULL)
1613: fatal("Error: remote port forwarding failed "
1614: "for listen path %s", rfwd->listen_path);
1615: else
1616: fatal("Error: remote port forwarding failed "
1617: "for listen port %d", rfwd->listen_port);
1618: } else {
1619: if (rfwd->listen_path != NULL)
1620: logit("Warning: remote port forwarding failed "
1621: "for listen path %s", rfwd->listen_path);
1622: else
1623: logit("Warning: remote port forwarding failed "
1624: "for listen port %d", rfwd->listen_port);
1625: }
1.315 djm 1626: }
1.318 djm 1627: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 1628: debug("All remote forwarding requests processed");
1.344 djm 1629: if (fork_after_authentication_flag)
1630: fork_postauth();
1.318 djm 1631: }
1.315 djm 1632: }
1633:
1.126 itojun 1634: static void
1.463 djm 1635: client_cleanup_stdio_fwd(struct ssh *ssh, int id, void *arg)
1.331 dtucker 1636: {
1637: debug("stdio forwarding: done");
1638: cleanup_exit(0);
1639: }
1640:
1.368 djm 1641: static void
1.463 djm 1642: ssh_stdio_confirm(struct ssh *ssh, int id, int success, void *arg)
1.407 djm 1643: {
1644: if (!success)
1645: fatal("stdio forwarding failed");
1646: }
1647:
1648: static void
1.463 djm 1649: ssh_init_stdio_forwarding(struct ssh *ssh)
1.331 dtucker 1650: {
1651: Channel *c;
1.332 djm 1652: int in, out;
1.331 dtucker 1653:
1.441 dtucker 1654: if (options.stdio_forward_host == NULL)
1.368 djm 1655: return;
1656:
1.441 dtucker 1657: debug3("%s: %s:%d", __func__, options.stdio_forward_host,
1658: options.stdio_forward_port);
1.332 djm 1659:
1.368 djm 1660: if ((in = dup(STDIN_FILENO)) < 0 ||
1661: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1662: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.463 djm 1663: if ((c = channel_connect_stdio_fwd(ssh, options.stdio_forward_host,
1.441 dtucker 1664: options.stdio_forward_port, in, out)) == NULL)
1.368 djm 1665: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.463 djm 1666: channel_register_cleanup(ssh, c->self, client_cleanup_stdio_fwd, 0);
1667: channel_register_open_confirm(ssh, c->self, ssh_stdio_confirm, NULL);
1.331 dtucker 1668: }
1669:
1670: static void
1.466 djm 1671: ssh_init_forwarding(struct ssh *ssh, char **ifname)
1.70 markus 1672: {
1.86 markus 1673: int success = 0;
1.70 markus 1674: int i;
1.331 dtucker 1675:
1.70 markus 1676: /* Initiate local TCP/IP port forwardings. */
1677: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1678: debug("Local connections to %.200s:%d forwarded to remote "
1679: "address %.200s:%d",
1.406 millert 1680: (options.local_forwards[i].listen_path != NULL) ?
1681: options.local_forwards[i].listen_path :
1.234 deraadt 1682: (options.local_forwards[i].listen_host == NULL) ?
1.406 millert 1683: (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1684: options.local_forwards[i].listen_host,
1685: options.local_forwards[i].listen_port,
1.406 millert 1686: (options.local_forwards[i].connect_path != NULL) ?
1687: options.local_forwards[i].connect_path :
1.232 djm 1688: options.local_forwards[i].connect_host,
1689: options.local_forwards[i].connect_port);
1.463 djm 1690: success += channel_setup_local_fwd_listener(ssh,
1.406 millert 1691: &options.local_forwards[i], &options.fwd_opts);
1.70 markus 1692: }
1.283 markus 1693: if (i > 0 && success != i && options.exit_on_forward_failure)
1694: fatal("Could not request local forwarding.");
1.86 markus 1695: if (i > 0 && success == 0)
1696: error("Could not request local forwarding.");
1.70 markus 1697:
1698: /* Initiate remote TCP/IP port forwardings. */
1699: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1700: debug("Remote connections from %.200s:%d forwarded to "
1701: "local address %.200s:%d",
1.406 millert 1702: (options.remote_forwards[i].listen_path != NULL) ?
1703: options.remote_forwards[i].listen_path :
1.248 djm 1704: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1705: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1706: options.remote_forwards[i].listen_port,
1.406 millert 1707: (options.remote_forwards[i].connect_path != NULL) ?
1708: options.remote_forwards[i].connect_path :
1.232 djm 1709: options.remote_forwards[i].connect_host,
1710: options.remote_forwards[i].connect_port);
1.366 markus 1711: options.remote_forwards[i].handle =
1.463 djm 1712: channel_request_remote_forwarding(ssh,
1.406 millert 1713: &options.remote_forwards[i]);
1.366 markus 1714: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1715: if (options.exit_on_forward_failure)
1716: fatal("Could not request remote forwarding.");
1717: else
1718: logit("Warning: Could not request remote "
1719: "forwarding.");
1.366 markus 1720: } else {
1.463 djm 1721: client_register_global_confirm(
1722: ssh_confirm_remote_forward,
1.366 markus 1723: &options.remote_forwards[i]);
1.283 markus 1724: }
1.70 markus 1725: }
1.301 djm 1726:
1727: /* Initiate tunnel forwarding. */
1728: if (options.tun_open != SSH_TUNMODE_NO) {
1.466 djm 1729: if ((*ifname = client_request_tun_fwd(ssh,
1730: options.tun_open, options.tun_local,
1731: options.tun_remote)) == NULL) {
1.301 djm 1732: if (options.exit_on_forward_failure)
1733: fatal("Could not request tunnel forwarding.");
1734: else
1735: error("Could not request tunnel forwarding.");
1736: }
1.468 djm 1737: }
1.70 markus 1738: }
1739:
1.126 itojun 1740: static void
1.70 markus 1741: check_agent_present(void)
1742: {
1.412 djm 1743: int r;
1744:
1.70 markus 1745: if (options.forward_agent) {
1.254 djm 1746: /* Clear agent forwarding if we don't have an agent. */
1.412 djm 1747: if ((r = ssh_get_authentication_socket(NULL)) != 0) {
1.70 markus 1748: options.forward_agent = 0;
1.412 djm 1749: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1750: debug("ssh_get_authentication_socket: %s",
1751: ssh_err(r));
1752: }
1.70 markus 1753: }
1754: }
1755:
1.214 djm 1756: static void
1.463 djm 1757: ssh_session2_setup(struct ssh *ssh, int id, int success, void *arg)
1.214 djm 1758: {
1.215 djm 1759: extern char **environ;
1.243 djm 1760: const char *display;
1761: int interactive = tty_flag;
1.433 djm 1762: char *proto = NULL, *data = NULL;
1.337 djm 1763:
1764: if (!success)
1765: return; /* No need for error message, channels code sens one */
1.215 djm 1766:
1.248 djm 1767: display = getenv("DISPLAY");
1.417 djm 1768: if (display == NULL && options.forward_x11)
1769: debug("X11 forwarding requested but DISPLAY not set");
1.463 djm 1770: if (options.forward_x11 && client_x11_get_proto(ssh, display,
1.433 djm 1771: options.xauth_location, options.forward_x11_trusted,
1772: options.forward_x11_timeout, &proto, &data) == 0) {
1.50 markus 1773: /* Request forwarding with authentication spoofing. */
1.316 djm 1774: debug("Requesting X11 forwarding with authentication "
1775: "spoofing.");
1.463 djm 1776: x11_request_forwarding_with_spoofing(ssh, id, display, proto,
1.363 djm 1777: data, 1);
1.463 djm 1778: client_expect_confirm(ssh, id, "X11 forwarding", CONFIRM_WARN);
1.363 djm 1779: /* XXX exit_on_forward_failure */
1.80 markus 1780: interactive = 1;
1.50 markus 1781: }
1782:
1.70 markus 1783: check_agent_present();
1784: if (options.forward_agent) {
1785: debug("Requesting authentication agent forwarding.");
1.463 djm 1786: channel_request_start(ssh, id, "auth-agent-req@openssh.com", 0);
1.70 markus 1787: packet_send();
1.212 djm 1788: }
1.369 dtucker 1789:
1790: /* Tell the packet module whether this is an interactive session. */
1791: packet_set_interactive(interactive,
1792: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1793:
1.463 djm 1794: client_session2_setup(ssh, id, tty_flag, subsystem_flag, getenv("TERM"),
1.482 markus 1795: NULL, fileno(stdin), command, environ);
1.45 markus 1796: }
1797:
1.143 markus 1798: /* open new channel for a session */
1.126 itojun 1799: static int
1.463 djm 1800: ssh_session2_open(struct ssh *ssh)
1.45 markus 1801: {
1.118 markus 1802: Channel *c;
1803: int window, packetmax, in, out, err;
1.60 markus 1804:
1.62 markus 1805: if (stdin_null_flag) {
1.93 itojun 1806: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1807: } else {
1808: in = dup(STDIN_FILENO);
1809: }
1.60 markus 1810: out = dup(STDOUT_FILENO);
1811: err = dup(STDERR_FILENO);
1.45 markus 1812:
1813: if (in < 0 || out < 0 || err < 0)
1.62 markus 1814: fatal("dup() in/out/err failed");
1.45 markus 1815:
1.69 markus 1816: /* enable nonblocking unless tty */
1817: if (!isatty(in))
1818: set_nonblock(in);
1819: if (!isatty(out))
1820: set_nonblock(out);
1821: if (!isatty(err))
1822: set_nonblock(err);
1823:
1.65 markus 1824: window = CHAN_SES_WINDOW_DEFAULT;
1825: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1826: if (tty_flag) {
1827: window >>= 1;
1828: packetmax >>= 1;
1.45 markus 1829: }
1.463 djm 1830: c = channel_new(ssh,
1.45 markus 1831: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1832: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1833: "client-session", /*nonblock*/0);
1.45 markus 1834:
1.463 djm 1835: debug3("%s: channel_new: %d", __func__, c->self);
1.106 markus 1836:
1.463 djm 1837: channel_send_open(ssh, c->self);
1.143 markus 1838: if (!no_shell_flag)
1.463 djm 1839: channel_register_open_confirm(ssh, c->self,
1.310 djm 1840: ssh_session2_setup, NULL);
1.106 markus 1841:
1.118 markus 1842: return c->self;
1.106 markus 1843: }
1844:
1.126 itojun 1845: static int
1.466 djm 1846: ssh_session2(struct ssh *ssh, struct passwd *pw)
1.106 markus 1847: {
1.467 djm 1848: int devnull, id = -1;
1.466 djm 1849: char *cp, *tun_fwd_ifname = NULL;
1.106 markus 1850:
1851: /* XXX should be pre-session */
1.368 djm 1852: if (!options.control_persist)
1.463 djm 1853: ssh_init_stdio_forwarding(ssh);
1.466 djm 1854:
1855: ssh_init_forwarding(ssh, &tun_fwd_ifname);
1856:
1857: if (options.local_command != NULL) {
1858: debug3("expanding LocalCommand: %s", options.local_command);
1859: cp = options.local_command;
1860: options.local_command = percent_expand(cp,
1861: "C", conn_hash_hex,
1862: "L", shorthost,
1863: "d", pw->pw_dir,
1864: "h", host,
1.479 djm 1865: "i", uidstr,
1.466 djm 1866: "l", thishost,
1867: "n", host_arg,
1868: "p", portstr,
1869: "r", options.user,
1870: "u", pw->pw_name,
1871: "T", tun_fwd_ifname == NULL ? "NONE" : tun_fwd_ifname,
1872: (char *)NULL);
1873: debug3("expanded LocalCommand: %s", options.local_command);
1874: free(cp);
1875: }
1.106 markus 1876:
1.344 djm 1877: /* Start listening for multiplex clients */
1.447 markus 1878: if (!packet_get_mux())
1.463 djm 1879: muxserver_listen(ssh);
1.344 djm 1880:
1.473 djm 1881: /*
1.368 djm 1882: * If we are in control persist mode and have a working mux listen
1883: * socket, then prepare to background ourselves and have a foreground
1884: * client attach as a control slave.
1885: * NB. we must save copies of the flags that we override for
1.344 djm 1886: * the backgrounding, since we defer attachment of the slave until
1887: * after the connection is fully established (in particular,
1888: * async rfwd replies have been received for ExitOnForwardFailure).
1889: */
1.473 djm 1890: if (options.control_persist && muxserver_sock != -1) {
1.344 djm 1891: ostdin_null_flag = stdin_null_flag;
1892: ono_shell_flag = no_shell_flag;
1.359 djm 1893: orequest_tty = options.request_tty;
1.344 djm 1894: otty_flag = tty_flag;
1.473 djm 1895: stdin_null_flag = 1;
1896: no_shell_flag = 1;
1897: tty_flag = 0;
1.344 djm 1898: if (!fork_after_authentication_flag)
1899: need_controlpersist_detach = 1;
1900: fork_after_authentication_flag = 1;
1.473 djm 1901: }
1.368 djm 1902: /*
1903: * ControlPersist mux listen socket setup failed, attempt the
1904: * stdio forward setup that we skipped earlier.
1905: */
1906: if (options.control_persist && muxserver_sock == -1)
1.463 djm 1907: ssh_init_stdio_forwarding(ssh);
1.344 djm 1908:
1.471 djm 1909: if (!no_shell_flag)
1.463 djm 1910: id = ssh_session2_open(ssh);
1.379 djm 1911: else {
1912: packet_set_interactive(
1913: options.control_master == SSHCTL_MASTER_NO,
1914: options.ip_qos_interactive, options.ip_qos_bulk);
1915: }
1.314 djm 1916:
1917: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1918: if (options.control_master == SSHCTL_MASTER_NO &&
1919: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1920: debug("Requesting no-more-sessions@openssh.com");
1921: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1922: packet_put_cstring("no-more-sessions@openssh.com");
1923: packet_put_char(0);
1924: packet_send();
1925: }
1.255 reyk 1926:
1927: /* Execute a local command */
1928: if (options.local_command != NULL &&
1929: options.permit_local_command)
1930: ssh_local_cmd(options.local_command);
1.467 djm 1931:
1932: /*
1933: * stdout is now owned by the session channel; clobber it here
1934: * so future channel closes are propagated to the local fd.
1935: * NB. this can only happen after LocalCommand has completed,
1936: * as it may want to write to stdout.
1937: */
1.469 djm 1938: if (!need_controlpersist_detach) {
1939: if ((devnull = open(_PATH_DEVNULL, O_WRONLY)) == -1)
1940: error("%s: open %s: %s", __func__,
1941: _PATH_DEVNULL, strerror(errno));
1942: if (dup2(devnull, STDOUT_FILENO) < 0)
1943: fatal("%s: dup2() stdout failed", __func__);
1944: if (devnull > STDERR_FILENO)
1945: close(devnull);
1946: }
1.301 djm 1947:
1.342 djm 1948: /*
1949: * If requested and we are not interested in replies to remote
1950: * forwarding requests, then let ssh continue in the background.
1951: */
1.344 djm 1952: if (fork_after_authentication_flag) {
1953: if (options.exit_on_forward_failure &&
1954: options.num_remote_forwards > 0) {
1955: debug("deferring postauth fork until remote forward "
1956: "confirmation received");
1957: } else
1958: fork_postauth();
1.318 djm 1959: }
1.31 markus 1960:
1.463 djm 1961: return client_loop(ssh, tty_flag, tty_flag ?
1.119 stevesk 1962: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1963: }
1964:
1.426 djm 1965: /* Loads all IdentityFile and CertificateFile keys */
1.126 itojun 1966: static void
1.466 djm 1967: load_public_identity_files(struct passwd *pw)
1.104 markus 1968: {
1.466 djm 1969: char *filename, *cp;
1.460 markus 1970: struct sshkey *public;
1.426 djm 1971: int i;
1972: u_int n_ids, n_certs;
1.335 djm 1973: char *identity_files[SSH_MAX_IDENTITY_FILES];
1.460 markus 1974: struct sshkey *identity_keys[SSH_MAX_IDENTITY_FILES];
1.484 djm 1975: int identity_file_userprovided[SSH_MAX_IDENTITY_FILES];
1.426 djm 1976: char *certificate_files[SSH_MAX_CERTIFICATE_FILES];
1977: struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
1.484 djm 1978: int certificate_file_userprovided[SSH_MAX_CERTIFICATE_FILES];
1.333 markus 1979: #ifdef ENABLE_PKCS11
1.460 markus 1980: struct sshkey **keys;
1.333 markus 1981: int nkeys;
1.335 djm 1982: #endif /* PKCS11 */
1.104 markus 1983:
1.426 djm 1984: n_ids = n_certs = 0;
1.398 tedu 1985: memset(identity_files, 0, sizeof(identity_files));
1986: memset(identity_keys, 0, sizeof(identity_keys));
1.484 djm 1987: memset(identity_file_userprovided, 0,
1988: sizeof(identity_file_userprovided));
1.426 djm 1989: memset(certificate_files, 0, sizeof(certificate_files));
1990: memset(certificates, 0, sizeof(certificates));
1.484 djm 1991: memset(certificate_file_userprovided, 0,
1992: sizeof(certificate_file_userprovided));
1.335 djm 1993:
1994: #ifdef ENABLE_PKCS11
1.333 markus 1995: if (options.pkcs11_provider != NULL &&
1.167 markus 1996: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 1997: (pkcs11_init(!options.batch_mode) == 0) &&
1998: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
1999: &keys)) > 0) {
2000: for (i = 0; i < nkeys; i++) {
1.335 djm 2001: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
1.483 markus 2002: sshkey_free(keys[i]);
1.335 djm 2003: continue;
2004: }
2005: identity_keys[n_ids] = keys[i];
2006: identity_files[n_ids] =
1.333 markus 2007: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 2008: n_ids++;
1.167 markus 2009: }
1.378 djm 2010: free(keys);
1.127 markus 2011: }
1.333 markus 2012: #endif /* ENABLE_PKCS11 */
1.275 djm 2013: if ((pw = getpwuid(original_real_uid)) == NULL)
2014: fatal("load_public_identity_files: getpwuid failed");
1.335 djm 2015: for (i = 0; i < options.num_identity_files; i++) {
1.373 djm 2016: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
2017: strcasecmp(options.identity_files[i], "none") == 0) {
1.378 djm 2018: free(options.identity_files[i]);
1.426 djm 2019: options.identity_files[i] = NULL;
1.335 djm 2020: continue;
2021: }
1.275 djm 2022: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 2023: original_real_uid);
1.466 djm 2024: filename = percent_expand(cp, "d", pw->pw_dir,
2025: "u", pw->pw_name, "l", thishost, "h", host,
1.275 djm 2026: "r", options.user, (char *)NULL);
1.378 djm 2027: free(cp);
1.483 markus 2028: check_load(sshkey_load_public(filename, &public, NULL),
2029: filename, "pubkey");
1.131 millert 2030: debug("identity file %s type %d", filename,
2031: public ? public->type : -1);
1.378 djm 2032: free(options.identity_files[i]);
1.335 djm 2033: identity_files[n_ids] = filename;
2034: identity_keys[n_ids] = public;
1.484 djm 2035: identity_file_userprovided[n_ids] =
2036: options.identity_file_userprovided[i];
1.335 djm 2037: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
2038: continue;
2039:
1.426 djm 2040: /*
2041: * If no certificates have been explicitly listed then try
2042: * to add the default certificate variant too.
2043: */
2044: if (options.num_certificate_files != 0)
2045: continue;
1.335 djm 2046: xasprintf(&cp, "%s-cert", filename);
1.483 markus 2047: check_load(sshkey_load_public(cp, &public, NULL),
2048: filename, "pubkey");
1.335 djm 2049: debug("identity file %s type %d", cp,
2050: public ? public->type : -1);
2051: if (public == NULL) {
1.378 djm 2052: free(cp);
1.335 djm 2053: continue;
2054: }
1.483 markus 2055: if (!sshkey_is_cert(public)) {
1.335 djm 2056: debug("%s: key %s type %s is not a certificate",
1.483 markus 2057: __func__, cp, sshkey_type(public));
2058: sshkey_free(public);
1.378 djm 2059: free(cp);
1.335 djm 2060: continue;
2061: }
1.448 djm 2062: /* NB. leave filename pointing to private key */
2063: identity_files[n_ids] = xstrdup(filename);
1.335 djm 2064: identity_keys[n_ids] = public;
1.484 djm 2065: identity_file_userprovided[n_ids] =
2066: options.identity_file_userprovided[i];
1.335 djm 2067: n_ids++;
2068: }
1.426 djm 2069:
2070: if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES)
2071: fatal("%s: too many certificates", __func__);
2072: for (i = 0; i < options.num_certificate_files; i++) {
2073: cp = tilde_expand_filename(options.certificate_files[i],
2074: original_real_uid);
1.479 djm 2075: filename = percent_expand(cp,
2076: "d", pw->pw_dir,
2077: "h", host,
1.481 djm 2078: "i", uidstr,
1.479 djm 2079: "l", thishost,
2080: "r", options.user,
2081: "u", pw->pw_name,
2082: (char *)NULL);
1.426 djm 2083: free(cp);
2084:
1.483 markus 2085: check_load(sshkey_load_public(filename, &public, NULL),
2086: filename, "certificate");
1.426 djm 2087: debug("certificate file %s type %d", filename,
2088: public ? public->type : -1);
2089: free(options.certificate_files[i]);
2090: options.certificate_files[i] = NULL;
2091: if (public == NULL) {
2092: free(filename);
2093: continue;
2094: }
1.483 markus 2095: if (!sshkey_is_cert(public)) {
1.426 djm 2096: debug("%s: key %s type %s is not a certificate",
1.483 markus 2097: __func__, filename, sshkey_type(public));
2098: sshkey_free(public);
1.426 djm 2099: free(filename);
2100: continue;
2101: }
2102: certificate_files[n_certs] = filename;
2103: certificates[n_certs] = public;
1.484 djm 2104: certificate_file_userprovided[n_certs] =
2105: options.certificate_file_userprovided[i];
1.426 djm 2106: ++n_certs;
2107: }
2108:
1.335 djm 2109: options.num_identity_files = n_ids;
2110: memcpy(options.identity_files, identity_files, sizeof(identity_files));
2111: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
1.484 djm 2112: memcpy(options.identity_file_userprovided,
2113: identity_file_userprovided, sizeof(identity_file_userprovided));
1.426 djm 2114:
2115: options.num_certificate_files = n_certs;
2116: memcpy(options.certificate_files,
2117: certificate_files, sizeof(certificate_files));
2118: memcpy(options.certificates, certificates, sizeof(certificates));
1.484 djm 2119: memcpy(options.certificate_file_userprovided,
2120: certificate_file_userprovided,
2121: sizeof(certificate_file_userprovided));
1.214 djm 2122: }
1.352 djm 2123:
2124: static void
2125: main_sigchld_handler(int sig)
2126: {
2127: int save_errno = errno;
2128: pid_t pid;
2129: int status;
2130:
2131: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
2132: (pid < 0 && errno == EINTR))
2133: ;
2134: errno = save_errno;
2135: }
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