Annotation of src/usr.bin/ssh/ssh.c, Revision 1.454
1.454 ! djm 1: /* $OpenBSD: ssh.c,v 1.453 2017/04/30 23:10:43 djm Exp $ */
1.1 deraadt 2: /*
1.32 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * Ssh client program. This program can be used to log into a remote machine.
7: * The software supports strong authentication, encryption, and forwarding
8: * of X11, TCP/IP, and authentication connections.
9: *
1.64 deraadt 10: * As far as I am concerned, the code I have written for this software
11: * can be used freely for any purpose. Any derived versions of this
12: * software must be clearly marked as such, and if the derived work is
13: * incompatible with the protocol description in the RFC file, it must be
14: * called by a name other than "ssh" or "Secure Shell".
15: *
16: * Copyright (c) 1999 Niels Provos. All rights reserved.
1.202 markus 17: * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved.
1.64 deraadt 18: *
19: * Modified to work with SSL by Niels Provos <provos@citi.umich.edu>
20: * in Canada (German citizen).
21: *
22: * Redistribution and use in source and binary forms, with or without
23: * modification, are permitted provided that the following conditions
24: * are met:
25: * 1. Redistributions of source code must retain the above copyright
26: * notice, this list of conditions and the following disclaimer.
27: * 2. Redistributions in binary form must reproduce the above copyright
28: * notice, this list of conditions and the following disclaimer in the
29: * documentation and/or other materials provided with the distribution.
30: *
31: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
32: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
34: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
35: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
36: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
37: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
38: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
39: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
40: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 deraadt 41: */
1.1 deraadt 42:
1.293 deraadt 43: #include <sys/types.h>
1.312 djm 44: #include <sys/ioctl.h>
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 "ssh1.h"
75: #include "ssh2.h"
1.341 djm 76: #include "canohost.h"
1.84 markus 77: #include "compat.h"
78: #include "cipher.h"
1.405 djm 79: #include "digest.h"
1.1 deraadt 80: #include "packet.h"
81: #include "buffer.h"
1.123 markus 82: #include "channels.h"
1.49 markus 83: #include "key.h"
1.58 markus 84: #include "authfd.h"
1.49 markus 85: #include "authfile.h"
1.83 markus 86: #include "pathnames.h"
1.214 djm 87: #include "dispatch.h"
1.81 markus 88: #include "clientloop.h"
1.84 markus 89: #include "log.h"
1.406 millert 90: #include "misc.h"
1.84 markus 91: #include "readconf.h"
92: #include "sshconnect.h"
1.95 markus 93: #include "kex.h"
94: #include "mac.h"
1.213 deraadt 95: #include "sshpty.h"
1.212 djm 96: #include "match.h"
1.214 djm 97: #include "msg.h"
1.225 dtucker 98: #include "uidswap.h"
1.278 stevesk 99: #include "version.h"
1.412 djm 100: #include "ssherr.h"
1.420 djm 101: #include "myproposal.h"
1.49 markus 102:
1.333 markus 103: #ifdef ENABLE_PKCS11
104: #include "ssh-pkcs11.h"
1.137 jakob 105: #endif
1.127 markus 106:
1.49 markus 107: extern char *__progname;
1.1 deraadt 108:
1.316 djm 109: /* Flag indicating whether debug mode is on. May be set on the command line. */
1.1 deraadt 110: int debug_flag = 0;
111:
1.359 djm 112: /* Flag indicating whether a tty should be requested */
1.1 deraadt 113: int tty_flag = 0;
114:
1.45 markus 115: /* don't exec a shell */
116: int no_shell_flag = 0;
117:
1.33 markus 118: /*
119: * Flag indicating that nothing should be read from stdin. This can be set
120: * on the command line.
121: */
1.1 deraadt 122: int stdin_null_flag = 0;
123:
1.33 markus 124: /*
1.344 djm 125: * Flag indicating that the current process should be backgrounded and
126: * a new slave launched in the foreground for ControlPersist.
127: */
128: int need_controlpersist_detach = 0;
129:
130: /* Copies of flags for ControlPersist foreground slave */
1.359 djm 131: int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty;
1.344 djm 132:
133: /*
1.33 markus 134: * Flag indicating that ssh should fork after authentication. This is useful
1.172 deraadt 135: * so that the passphrase can be entered manually, and then ssh goes to the
1.33 markus 136: * background.
137: */
1.1 deraadt 138: int fork_after_authentication_flag = 0;
139:
1.33 markus 140: /*
141: * General data structure for command line options and options configurable
142: * in configuration files. See readconf.h.
143: */
1.1 deraadt 144: Options options;
145:
1.139 markus 146: /* optional user configfile */
147: char *config = NULL;
148:
1.33 markus 149: /*
150: * Name of the host we are connecting to. This is the name given on the
151: * command line, or the HostName specified for the user-supplied name in a
152: * configuration file.
153: */
1.1 deraadt 154: char *host;
155:
1.22 provos 156: /* socket address the host resolves to */
1.37 markus 157: struct sockaddr_storage hostaddr;
1.1 deraadt 158:
1.112 markus 159: /* Private host keys. */
1.173 markus 160: Sensitive sensitive_data;
1.1 deraadt 161:
1.10 dugsong 162: /* Original real UID. */
163: uid_t original_real_uid;
1.177 markus 164: uid_t original_effective_uid;
1.1 deraadt 165:
1.45 markus 166: /* command to be executed */
167: Buffer command;
168:
1.85 djm 169: /* Should we execute a command or invoke a subsystem? */
170: int subsystem_flag = 0;
171:
1.170 markus 172: /* # of replies received for global requests */
1.315 djm 173: static int remote_forward_confirms_received = 0;
1.170 markus 174:
1.313 djm 175: /* mux.c */
176: extern int muxserver_sock;
177: extern u_int muxclient_command;
178:
1.1 deraadt 179: /* Prints a help message to the user. This function never returns. */
180:
1.126 itojun 181: static void
1.93 itojun 182: usage(void)
1.1 deraadt 183: {
1.208 markus 184: fprintf(stderr,
1.409 jmc 185: "usage: ssh [-1246AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n"
1.375 dtucker 186: " [-D [bind_address:]port] [-E log_file] [-e escape_char]\n"
1.444 jmc 187: " [-F configfile] [-I pkcs11] [-i identity_file]\n"
188: " [-J [user@]host[:port]] [-L address] [-l login_name] [-m mac_spec]\n"
189: " [-O ctl_cmd] [-o option] [-p port] [-Q query_option] [-R address]\n"
190: " [-S ctl_path] [-W host:port] [-w local_tun[:remote_tun]]\n"
191: " [user@]hostname [command]\n"
1.208 markus 192: );
1.257 dtucker 193: exit(255);
1.1 deraadt 194: }
195:
1.126 itojun 196: static int ssh_session(void);
197: static int ssh_session2(void);
198: static void load_public_identity_files(void);
1.352 djm 199: static void main_sigchld_handler(int);
1.312 djm 200:
1.361 djm 201: /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */
202: static void
203: tilde_expand_paths(char **paths, u_int num_paths)
204: {
205: u_int i;
206: char *cp;
207:
208: for (i = 0; i < num_paths; i++) {
209: cp = tilde_expand_filename(paths[i], original_real_uid);
1.378 djm 210: free(paths[i]);
1.361 djm 211: paths[i] = cp;
212: }
213: }
214:
1.400 djm 215: /*
216: * Attempt to resolve a host name / port to a set of addresses and
217: * optionally return any CNAMEs encountered along the way.
218: * Returns NULL on failure.
219: * NB. this function must operate with a options having undefined members.
220: */
1.385 djm 221: static struct addrinfo *
1.400 djm 222: resolve_host(const char *name, int port, int logerr, char *cname, size_t clen)
1.385 djm 223: {
224: char strport[NI_MAXSERV];
225: struct addrinfo hints, *res;
226: int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1;
227:
1.400 djm 228: if (port <= 0)
229: port = default_ssh_port();
230:
1.427 djm 231: snprintf(strport, sizeof strport, "%d", port);
1.398 tedu 232: memset(&hints, 0, sizeof(hints));
1.400 djm 233: hints.ai_family = options.address_family == -1 ?
234: AF_UNSPEC : options.address_family;
1.385 djm 235: hints.ai_socktype = SOCK_STREAM;
236: if (cname != NULL)
237: hints.ai_flags = AI_CANONNAME;
238: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
239: if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA))
240: loglevel = SYSLOG_LEVEL_ERROR;
241: do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s",
242: __progname, name, ssh_gai_strerror(gaierr));
243: return NULL;
244: }
245: if (cname != NULL && res->ai_canonname != NULL) {
246: if (strlcpy(cname, res->ai_canonname, clen) >= clen) {
247: error("%s: host \"%s\" cname \"%s\" too long (max %lu)",
248: __func__, name, res->ai_canonname, (u_long)clen);
249: if (clen > 0)
250: *cname = '\0';
251: }
252: }
253: return res;
254: }
255:
256: /*
1.413 djm 257: * Attempt to resolve a numeric host address / port to a single address.
258: * Returns a canonical address string.
259: * Returns NULL on failure.
260: * NB. this function must operate with a options having undefined members.
261: */
262: static struct addrinfo *
263: resolve_addr(const char *name, int port, char *caddr, size_t clen)
264: {
265: char addr[NI_MAXHOST], strport[NI_MAXSERV];
266: struct addrinfo hints, *res;
267: int gaierr;
268:
269: if (port <= 0)
270: port = default_ssh_port();
271: snprintf(strport, sizeof strport, "%u", port);
272: memset(&hints, 0, sizeof(hints));
273: hints.ai_family = options.address_family == -1 ?
274: AF_UNSPEC : options.address_family;
275: hints.ai_socktype = SOCK_STREAM;
276: hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV;
277: if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) {
278: debug2("%s: could not resolve name %.100s as address: %s",
279: __func__, name, ssh_gai_strerror(gaierr));
280: return NULL;
281: }
282: if (res == NULL) {
283: debug("%s: getaddrinfo %.100s returned no addresses",
284: __func__, name);
285: return NULL;
286: }
287: if (res->ai_next != NULL) {
288: debug("%s: getaddrinfo %.100s returned multiple addresses",
289: __func__, name);
290: goto fail;
291: }
292: if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen,
293: addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) {
294: debug("%s: Could not format address for name %.100s: %s",
295: __func__, name, ssh_gai_strerror(gaierr));
296: goto fail;
297: }
298: if (strlcpy(caddr, addr, clen) >= clen) {
299: error("%s: host \"%s\" addr \"%s\" too long (max %lu)",
300: __func__, name, addr, (u_long)clen);
301: if (clen > 0)
302: *caddr = '\0';
303: fail:
304: freeaddrinfo(res);
305: return NULL;
306: }
307: return res;
308: }
309:
310: /*
1.385 djm 311: * Check whether the cname is a permitted replacement for the hostname
312: * and perform the replacement if it is.
1.400 djm 313: * NB. this function must operate with a options having undefined members.
1.385 djm 314: */
315: static int
1.443 djm 316: check_follow_cname(int direct, char **namep, const char *cname)
1.385 djm 317: {
318: int i;
319: struct allowed_cname *rule;
320:
321: if (*cname == '\0' || options.num_permitted_cnames == 0 ||
322: strcmp(*namep, cname) == 0)
323: return 0;
1.386 djm 324: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
1.385 djm 325: return 0;
326: /*
1.386 djm 327: * Don't attempt to canonicalize names that will be interpreted by
1.443 djm 328: * a proxy or jump host unless the user specifically requests so.
1.385 djm 329: */
1.443 djm 330: if (!direct &&
1.386 djm 331: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
1.385 djm 332: return 0;
333: debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname);
334: for (i = 0; i < options.num_permitted_cnames; i++) {
335: rule = options.permitted_cnames + i;
1.418 djm 336: if (match_pattern_list(*namep, rule->source_list, 1) != 1 ||
337: match_pattern_list(cname, rule->target_list, 1) != 1)
1.385 djm 338: continue;
1.386 djm 339: verbose("Canonicalized DNS aliased hostname "
1.385 djm 340: "\"%s\" => \"%s\"", *namep, cname);
341: free(*namep);
342: *namep = xstrdup(cname);
343: return 1;
344: }
345: return 0;
346: }
347:
348: /*
349: * Attempt to resolve the supplied hostname after applying the user's
1.387 djm 350: * canonicalization rules. Returns the address list for the host or NULL
351: * if no name was found after canonicalization.
1.400 djm 352: * NB. this function must operate with a options having undefined members.
1.385 djm 353: */
354: static struct addrinfo *
1.400 djm 355: resolve_canonicalize(char **hostp, int port)
1.385 djm 356: {
1.443 djm 357: int i, direct, ndots;
1.413 djm 358: char *cp, *fullhost, newname[NI_MAXHOST];
1.385 djm 359: struct addrinfo *addrs;
360:
1.386 djm 361: if (options.canonicalize_hostname == SSH_CANONICALISE_NO)
1.385 djm 362: return NULL;
1.400 djm 363:
1.385 djm 364: /*
1.386 djm 365: * Don't attempt to canonicalize names that will be interpreted by
1.385 djm 366: * a proxy unless the user specifically requests so.
367: */
1.443 djm 368: direct = option_clear_or_none(options.proxy_command) &&
369: options.jump_host == NULL;
370: if (!direct &&
1.386 djm 371: options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS)
1.385 djm 372: return NULL;
1.400 djm 373:
1.413 djm 374: /* Try numeric hostnames first */
375: if ((addrs = resolve_addr(*hostp, port,
376: newname, sizeof(newname))) != NULL) {
377: debug2("%s: hostname %.100s is address", __func__, *hostp);
378: if (strcasecmp(*hostp, newname) != 0) {
379: debug2("%s: canonicalised address \"%s\" => \"%s\"",
380: __func__, *hostp, newname);
381: free(*hostp);
382: *hostp = xstrdup(newname);
383: }
384: return addrs;
385: }
386:
1.428 djm 387: /* If domain name is anchored, then resolve it now */
388: if ((*hostp)[strlen(*hostp) - 1] == '.') {
389: debug3("%s: name is fully qualified", __func__);
390: fullhost = xstrdup(*hostp);
391: if ((addrs = resolve_host(fullhost, port, 0,
392: newname, sizeof(newname))) != NULL)
393: goto found;
394: free(fullhost);
395: goto notfound;
396: }
397:
1.387 djm 398: /* Don't apply canonicalization to sufficiently-qualified hostnames */
1.385 djm 399: ndots = 0;
400: for (cp = *hostp; *cp != '\0'; cp++) {
401: if (*cp == '.')
402: ndots++;
403: }
1.386 djm 404: if (ndots > options.canonicalize_max_dots) {
405: debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)",
406: __func__, *hostp, options.canonicalize_max_dots);
1.385 djm 407: return NULL;
408: }
409: /* Attempt each supplied suffix */
410: for (i = 0; i < options.num_canonical_domains; i++) {
1.413 djm 411: *newname = '\0';
1.385 djm 412: xasprintf(&fullhost, "%s.%s.", *hostp,
413: options.canonical_domains[i]);
1.400 djm 414: debug3("%s: attempting \"%s\" => \"%s\"", __func__,
415: *hostp, fullhost);
416: if ((addrs = resolve_host(fullhost, port, 0,
1.413 djm 417: newname, sizeof(newname))) == NULL) {
1.385 djm 418: free(fullhost);
419: continue;
420: }
1.428 djm 421: found:
1.385 djm 422: /* Remove trailing '.' */
423: fullhost[strlen(fullhost) - 1] = '\0';
424: /* Follow CNAME if requested */
1.443 djm 425: if (!check_follow_cname(direct, &fullhost, newname)) {
1.386 djm 426: debug("Canonicalized hostname \"%s\" => \"%s\"",
1.385 djm 427: *hostp, fullhost);
428: }
429: free(*hostp);
430: *hostp = fullhost;
431: return addrs;
432: }
1.428 djm 433: notfound:
1.386 djm 434: if (!options.canonicalize_fallback_local)
1.400 djm 435: fatal("%s: Could not resolve host \"%s\"", __progname, *hostp);
436: debug2("%s: host %s not found in any suffix", __func__, *hostp);
1.385 djm 437: return NULL;
438: }
439:
1.32 deraadt 440: /*
1.400 djm 441: * Read per-user configuration file. Ignore the system wide config
442: * file if the user specifies a config file on the command line.
443: */
444: static void
1.408 djm 445: process_config_files(const char *host_arg, struct passwd *pw, int post_canon)
1.400 djm 446: {
1.414 deraadt 447: char buf[PATH_MAX];
1.400 djm 448: int r;
449:
450: if (config != NULL) {
451: if (strcasecmp(config, "none") != 0 &&
1.408 djm 452: !read_config_file(config, pw, host, host_arg, &options,
453: SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0)))
1.400 djm 454: fatal("Can't open user config file %.100s: "
455: "%.100s", config, strerror(errno));
456: } else {
457: r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir,
458: _PATH_SSH_USER_CONFFILE);
459: if (r > 0 && (size_t)r < sizeof(buf))
1.408 djm 460: (void)read_config_file(buf, pw, host, host_arg,
461: &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF |
462: (post_canon ? SSHCONF_POSTCANON : 0));
1.400 djm 463:
464: /* Read systemwide configuration file after user config. */
1.408 djm 465: (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw,
466: host, host_arg, &options,
467: post_canon ? SSHCONF_POSTCANON : 0);
468: }
469: }
470:
471: /* Rewrite the port number in an addrinfo list of addresses */
472: static void
473: set_addrinfo_port(struct addrinfo *addrs, int port)
474: {
475: struct addrinfo *addr;
476:
477: for (addr = addrs; addr != NULL; addr = addr->ai_next) {
478: switch (addr->ai_family) {
479: case AF_INET:
480: ((struct sockaddr_in *)addr->ai_addr)->
481: sin_port = htons(port);
482: break;
483: case AF_INET6:
484: ((struct sockaddr_in6 *)addr->ai_addr)->
485: sin6_port = htons(port);
486: break;
487: }
1.400 djm 488: }
489: }
490:
491: /*
1.32 deraadt 492: * Main program for the ssh client.
493: */
1.2 provos 494: int
495: main(int ac, char **av)
1.1 deraadt 496: {
1.437 djm 497: struct ssh *ssh = NULL;
1.443 djm 498: int i, r, opt, exit_status, use_syslog, direct, config_test = 0;
1.414 deraadt 499: char *p, *cp, *line, *argv0, buf[PATH_MAX], *host_arg, *logfile;
1.358 djm 500: char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV];
1.423 djm 501: char cname[NI_MAXHOST], uidstr[32], *conn_hash_hex;
1.31 markus 502: struct stat st;
1.98 markus 503: struct passwd *pw;
1.382 djm 504: int timeout_ms;
1.144 stevesk 505: extern int optind, optreset;
506: extern char *optarg;
1.406 millert 507: struct Forward fwd;
1.385 djm 508: struct addrinfo *addrs = NULL;
1.405 djm 509: struct ssh_digest_ctx *md;
510: u_char conn_hash[SSH_DIGEST_MAX_LENGTH];
1.250 djm 511:
1.436 dtucker 512: ssh_malloc_init(); /* must be called before any mallocs */
1.250 djm 513: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
514: sanitise_stdfd();
1.31 markus 515:
1.33 markus 516: /*
1.346 djm 517: * Discard other fds that are hanging around. These can cause problem
518: * with backgrounded ssh processes started by ControlPersist.
519: */
520: closefrom(STDERR_FILENO + 1);
521:
522: /*
1.33 markus 523: * Save the original real uid. It will be needed later (uid-swapping
524: * may clobber the real uid).
525: */
1.31 markus 526: original_real_uid = getuid();
527: original_effective_uid = geteuid();
528:
1.184 stevesk 529: /*
530: * Use uid-swapping to give up root privileges for the duration of
531: * option processing. We will re-instantiate the rights when we are
532: * ready to create the privileged port, and will permanently drop
533: * them when the port has been created (actually, when the connection
534: * has been made, as we may need to create the port several times).
535: */
536: PRIV_END;
537:
1.31 markus 538: /* If we are installed setuid root be careful to not drop core. */
539: if (original_real_uid != original_effective_uid) {
540: struct rlimit rlim;
541: rlim.rlim_cur = rlim.rlim_max = 0;
542: if (setrlimit(RLIMIT_CORE, &rlim) < 0)
543: fatal("setrlimit failed: %.100s", strerror(errno));
1.1 deraadt 544: }
1.107 markus 545: /* Get user data. */
546: pw = getpwuid(original_real_uid);
547: if (!pw) {
1.380 djm 548: logit("No user exists for uid %lu", (u_long)original_real_uid);
1.257 dtucker 549: exit(255);
1.107 markus 550: }
551: /* Take a copy of the returned structure. */
552: pw = pwcopy(pw);
1.31 markus 553:
1.33 markus 554: /*
555: * Set our umask to something reasonable, as some files are created
556: * with the default umask. This will make them world-readable but
557: * writable only by the owner, which is ok for all files for which we
558: * don't set the modes explicitly.
559: */
1.31 markus 560: umask(022);
1.445 djm 561:
562: setlocale(LC_CTYPE, "");
1.31 markus 563:
1.316 djm 564: /*
565: * Initialize option structure to indicate that no values have been
566: * set.
567: */
1.31 markus 568: initialize_options(&options);
569:
570: /* Parse command-line arguments. */
571: host = NULL;
1.320 djm 572: use_syslog = 0;
1.375 dtucker 573: logfile = NULL;
1.325 markus 574: argv0 = av[0];
1.31 markus 575:
1.266 djm 576: again:
1.316 djm 577: while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx"
1.443 djm 578: "ACD:E:F:GI:J:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) {
1.31 markus 579: switch (opt) {
1.91 jakob 580: case '1':
1.454 ! djm 581: fatal("SSH protocol v.1 is no longer supported");
1.91 jakob 582: break;
1.47 markus 583: case '2':
1.454 ! djm 584: /* Ignored */
1.47 markus 585: break;
1.37 markus 586: case '4':
1.196 djm 587: options.address_family = AF_INET;
1.37 markus 588: break;
589: case '6':
1.196 djm 590: options.address_family = AF_INET6;
1.37 markus 591: break;
1.31 markus 592: case 'n':
593: stdin_null_flag = 1;
594: break;
595: case 'f':
596: fork_after_authentication_flag = 1;
597: stdin_null_flag = 1;
598: break;
599: case 'x':
600: options.forward_x11 = 0;
601: break;
602: case 'X':
603: options.forward_x11 = 1;
604: break;
1.320 djm 605: case 'y':
606: use_syslog = 1;
607: break;
1.375 dtucker 608: case 'E':
1.422 dtucker 609: logfile = optarg;
1.375 dtucker 610: break;
1.408 djm 611: case 'G':
612: config_test = 1;
613: break;
1.202 markus 614: case 'Y':
615: options.forward_x11 = 1;
616: options.forward_x11_trusted = 1;
617: break;
1.31 markus 618: case 'g':
1.406 millert 619: options.fwd_opts.gateway_ports = 1;
1.31 markus 620: break;
1.229 djm 621: case 'O':
1.441 dtucker 622: if (options.stdio_forward_host != NULL)
1.332 djm 623: fatal("Cannot specify multiplexing "
624: "command with -W");
625: else if (muxclient_command != 0)
626: fatal("Multiplexing command already specified");
1.229 djm 627: if (strcmp(optarg, "check") == 0)
1.312 djm 628: muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
1.338 markus 629: else if (strcmp(optarg, "forward") == 0)
630: muxclient_command = SSHMUX_COMMAND_FORWARD;
1.229 djm 631: else if (strcmp(optarg, "exit") == 0)
1.312 djm 632: muxclient_command = SSHMUX_COMMAND_TERMINATE;
1.357 djm 633: else if (strcmp(optarg, "stop") == 0)
634: muxclient_command = SSHMUX_COMMAND_STOP;
1.365 djm 635: else if (strcmp(optarg, "cancel") == 0)
636: muxclient_command = SSHMUX_COMMAND_CANCEL_FWD;
1.447 markus 637: else if (strcmp(optarg, "proxy") == 0)
638: muxclient_command = SSHMUX_COMMAND_PROXY;
1.229 djm 639: else
640: fatal("Invalid multiplex command.");
641: break;
1.183 stevesk 642: case 'P': /* deprecated */
1.31 markus 643: options.use_privileged_port = 0;
1.376 djm 644: break;
1.394 deraadt 645: case 'Q':
1.376 djm 646: cp = NULL;
1.394 deraadt 647: if (strcmp(optarg, "cipher") == 0)
1.393 djm 648: cp = cipher_alg_list('\n', 0);
1.394 deraadt 649: else if (strcmp(optarg, "cipher-auth") == 0)
1.393 djm 650: cp = cipher_alg_list('\n', 1);
1.394 deraadt 651: else if (strcmp(optarg, "mac") == 0)
1.392 dtucker 652: cp = mac_alg_list('\n');
1.394 deraadt 653: else if (strcmp(optarg, "kex") == 0)
1.392 dtucker 654: cp = kex_alg_list('\n');
1.394 deraadt 655: else if (strcmp(optarg, "key") == 0)
1.451 djm 656: cp = sshkey_alg_list(0, 0, 0, '\n');
1.396 markus 657: else if (strcmp(optarg, "key-cert") == 0)
1.451 djm 658: cp = sshkey_alg_list(1, 0, 0, '\n');
1.396 markus 659: else if (strcmp(optarg, "key-plain") == 0)
1.451 djm 660: cp = sshkey_alg_list(0, 1, 0, '\n');
1.416 djm 661: else if (strcmp(optarg, "protocol-version") == 0) {
662: cp = xstrdup("2");
663: }
1.376 djm 664: if (cp == NULL)
665: fatal("Unsupported query \"%s\"", optarg);
666: printf("%s\n", cp);
667: free(cp);
668: exit(0);
1.31 markus 669: break;
670: case 'a':
671: options.forward_agent = 0;
1.53 markus 672: break;
673: case 'A':
674: options.forward_agent = 1;
1.31 markus 675: break;
676: case 'k':
1.204 dtucker 677: options.gss_deleg_creds = 0;
1.297 djm 678: break;
679: case 'K':
680: options.gss_authentication = 1;
681: options.gss_deleg_creds = 1;
1.31 markus 682: break;
683: case 'i':
1.429 dtucker 684: p = tilde_expand_filename(optarg, original_real_uid);
685: if (stat(p, &st) < 0)
1.128 fgsch 686: fprintf(stderr, "Warning: Identity file %s "
1.429 dtucker 687: "not accessible: %s.\n", p,
1.231 otto 688: strerror(errno));
1.429 dtucker 689: else
690: add_identity_file(&options, NULL, p, 1);
691: free(p);
1.31 markus 692: break;
1.127 markus 693: case 'I':
1.333 markus 694: #ifdef ENABLE_PKCS11
1.422 dtucker 695: free(options.pkcs11_provider);
1.333 markus 696: options.pkcs11_provider = xstrdup(optarg);
1.137 jakob 697: #else
1.333 markus 698: fprintf(stderr, "no support for PKCS#11.\n");
1.137 jakob 699: #endif
1.127 markus 700: break;
1.443 djm 701: case 'J':
702: if (options.jump_host != NULL)
703: fatal("Only a single -J option permitted");
704: if (options.proxy_command != NULL)
705: fatal("Cannot specify -J with ProxyCommand");
706: if (parse_jump(optarg, &options, 1) == -1)
707: fatal("Invalid -J argument");
708: options.proxy_command = xstrdup("none");
709: break;
1.31 markus 710: case 't':
1.359 djm 711: if (options.request_tty == REQUEST_TTY_YES)
712: options.request_tty = REQUEST_TTY_FORCE;
713: else
714: options.request_tty = REQUEST_TTY_YES;
1.31 markus 715: break;
716: case 'v':
1.197 markus 717: if (debug_flag == 0) {
1.66 markus 718: debug_flag = 1;
719: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.197 markus 720: } else {
1.443 djm 721: if (options.log_level < SYSLOG_LEVEL_DEBUG3) {
722: debug_flag++;
1.197 markus 723: options.log_level++;
1.443 djm 724: }
1.197 markus 725: }
1.375 dtucker 726: break;
1.31 markus 727: case 'V':
1.209 markus 728: fprintf(stderr, "%s, %s\n",
1.402 markus 729: SSH_VERSION,
730: #ifdef WITH_OPENSSL
731: SSLeay_version(SSLEAY_VERSION)
732: #else
733: "without OpenSSL"
734: #endif
735: );
1.31 markus 736: if (opt == 'V')
737: exit(0);
738: break;
1.255 reyk 739: case 'w':
1.256 reyk 740: if (options.tun_open == -1)
741: options.tun_open = SSH_TUNMODE_DEFAULT;
1.255 reyk 742: options.tun_local = a2tun(optarg, &options.tun_remote);
1.256 reyk 743: if (options.tun_local == SSH_TUNID_ERR) {
1.316 djm 744: fprintf(stderr,
745: "Bad tun device '%s'\n", optarg);
1.257 dtucker 746: exit(255);
1.255 reyk 747: }
748: break;
1.331 dtucker 749: case 'W':
1.441 dtucker 750: if (options.stdio_forward_host != NULL)
1.332 djm 751: fatal("stdio forward already specified");
752: if (muxclient_command != 0)
753: fatal("Cannot specify stdio forward with -O");
1.331 dtucker 754: if (parse_forward(&fwd, optarg, 1, 0)) {
1.441 dtucker 755: options.stdio_forward_host = fwd.listen_host;
756: options.stdio_forward_port = fwd.listen_port;
1.378 djm 757: free(fwd.connect_host);
1.331 dtucker 758: } else {
759: fprintf(stderr,
760: "Bad stdio forwarding specification '%s'\n",
761: optarg);
762: exit(255);
763: }
1.359 djm 764: options.request_tty = REQUEST_TTY_NO;
1.331 dtucker 765: no_shell_flag = 1;
766: break;
1.31 markus 767: case 'q':
768: options.log_level = SYSLOG_LEVEL_QUIET;
769: break;
770: case 'e':
771: if (optarg[0] == '^' && optarg[2] == 0 &&
1.128 fgsch 772: (u_char) optarg[1] >= 64 &&
773: (u_char) optarg[1] < 128)
1.78 markus 774: options.escape_char = (u_char) optarg[1] & 31;
1.31 markus 775: else if (strlen(optarg) == 1)
1.78 markus 776: options.escape_char = (u_char) optarg[0];
1.31 markus 777: else if (strcmp(optarg, "none") == 0)
1.119 stevesk 778: options.escape_char = SSH_ESCAPECHAR_NONE;
1.31 markus 779: else {
1.128 fgsch 780: fprintf(stderr, "Bad escape character '%s'.\n",
781: optarg);
1.257 dtucker 782: exit(255);
1.31 markus 783: }
784: break;
785: case 'c':
1.420 djm 786: if (ciphers_valid(*optarg == '+' ?
787: optarg + 1 : optarg)) {
1.49 markus 788: /* SSH2 only */
1.422 dtucker 789: free(options.ciphers);
1.49 markus 790: options.ciphers = xstrdup(optarg);
1.224 markus 791: options.cipher = SSH_CIPHER_INVALID;
1.420 djm 792: break;
793: }
794: /* SSH1 only */
795: options.cipher = cipher_number(optarg);
796: if (options.cipher == -1) {
797: fprintf(stderr, "Unknown cipher type '%s'\n",
798: optarg);
799: exit(255);
1.95 markus 800: }
1.420 djm 801: if (options.cipher == SSH_CIPHER_3DES)
802: options.ciphers = xstrdup("3des-cbc");
803: else if (options.cipher == SSH_CIPHER_BLOWFISH)
804: options.ciphers = xstrdup("blowfish-cbc");
805: else
806: options.ciphers = xstrdup(KEX_CLIENT_ENCRYPT);
1.95 markus 807: break;
808: case 'm':
1.422 dtucker 809: if (mac_valid(optarg)) {
810: free(options.macs);
1.95 markus 811: options.macs = xstrdup(optarg);
1.422 dtucker 812: } else {
1.128 fgsch 813: fprintf(stderr, "Unknown mac type '%s'\n",
814: optarg);
1.257 dtucker 815: exit(255);
1.31 markus 816: }
817: break;
1.214 djm 818: case 'M':
1.242 djm 819: if (options.control_master == SSHCTL_MASTER_YES)
820: options.control_master = SSHCTL_MASTER_ASK;
821: else
822: options.control_master = SSHCTL_MASTER_YES;
1.214 djm 823: break;
1.31 markus 824: case 'p':
1.113 stevesk 825: options.port = a2port(optarg);
1.323 djm 826: if (options.port <= 0) {
1.109 markus 827: fprintf(stderr, "Bad port '%s'\n", optarg);
1.257 dtucker 828: exit(255);
1.109 markus 829: }
1.31 markus 830: break;
831: case 'l':
832: options.user = optarg;
833: break;
1.141 stevesk 834:
835: case 'L':
1.324 djm 836: if (parse_forward(&fwd, optarg, 0, 0))
1.232 djm 837: add_local_forward(&options, &fwd);
838: else {
1.128 fgsch 839: fprintf(stderr,
1.232 djm 840: "Bad local forwarding specification '%s'\n",
1.128 fgsch 841: optarg);
1.257 dtucker 842: exit(255);
1.31 markus 843: }
1.232 djm 844: break;
845:
846: case 'R':
1.324 djm 847: if (parse_forward(&fwd, optarg, 0, 1)) {
1.232 djm 848: add_remote_forward(&options, &fwd);
849: } else {
1.128 fgsch 850: fprintf(stderr,
1.232 djm 851: "Bad remote forwarding specification "
852: "'%s'\n", optarg);
1.257 dtucker 853: exit(255);
1.31 markus 854: }
855: break;
1.108 markus 856:
857: case 'D':
1.324 djm 858: if (parse_forward(&fwd, optarg, 1, 0)) {
1.322 stevesk 859: add_local_forward(&options, &fwd);
1.232 djm 860: } else {
1.322 stevesk 861: fprintf(stderr,
862: "Bad dynamic forwarding specification "
863: "'%s'\n", optarg);
1.257 dtucker 864: exit(255);
1.109 markus 865: }
1.108 markus 866: break;
867:
1.31 markus 868: case 'C':
869: options.compression = 1;
870: break;
1.45 markus 871: case 'N':
872: no_shell_flag = 1;
1.359 djm 873: options.request_tty = REQUEST_TTY_NO;
1.45 markus 874: break;
875: case 'T':
1.359 djm 876: options.request_tty = REQUEST_TTY_NO;
1.45 markus 877: break;
1.31 markus 878: case 'o':
1.205 markus 879: line = xstrdup(optarg);
1.408 djm 880: if (process_config_line(&options, pw,
881: host ? host : "", host ? host : "", line,
882: "command-line", 0, NULL, SSHCONF_USERCONF) != 0)
1.257 dtucker 883: exit(255);
1.378 djm 884: free(line);
1.31 markus 885: break;
1.85 djm 886: case 's':
887: subsystem_flag = 1;
1.117 markus 888: break;
1.214 djm 889: case 'S':
1.431 mmcc 890: free(options.control_path);
1.214 djm 891: options.control_path = xstrdup(optarg);
892: break;
1.117 markus 893: case 'b':
894: options.bind_address = optarg;
1.85 djm 895: break;
1.139 markus 896: case 'F':
897: config = optarg;
898: break;
1.31 markus 899: default:
900: usage();
1.1 deraadt 901: }
1.31 markus 902: }
903:
1.128 fgsch 904: ac -= optind;
905: av += optind;
906:
1.329 guenther 907: if (ac > 0 && !host) {
1.188 markus 908: if (strrchr(*av, '@')) {
1.128 fgsch 909: p = xstrdup(*av);
1.188 markus 910: cp = strrchr(p, '@');
1.128 fgsch 911: if (cp == NULL || cp == p)
912: usage();
913: options.user = p;
914: *cp = '\0';
1.385 djm 915: host = xstrdup(++cp);
1.128 fgsch 916: } else
1.385 djm 917: host = xstrdup(*av);
1.189 millert 918: if (ac > 1) {
919: optind = optreset = 1;
1.128 fgsch 920: goto again;
921: }
1.189 millert 922: ac--, av++;
1.128 fgsch 923: }
924:
1.31 markus 925: /* Check that we got a host name. */
926: if (!host)
927: usage();
928:
1.385 djm 929: host_arg = xstrdup(host);
930:
1.402 markus 931: #ifdef WITH_OPENSSL
1.350 djm 932: OpenSSL_add_all_algorithms();
1.72 markus 933: ERR_load_crypto_strings();
1.402 markus 934: #endif
1.31 markus 935:
936: /* Initialize the command to execute on remote host. */
937: buffer_init(&command);
1.1 deraadt 938:
1.33 markus 939: /*
940: * Save the command to execute on the remote host in a buffer. There
941: * is no limit on the length of the command, except by the maximum
942: * packet size. Also sets the tty flag if there is no command.
943: */
1.128 fgsch 944: if (!ac) {
1.31 markus 945: /* No command specified - execute shell on a tty. */
1.85 djm 946: if (subsystem_flag) {
1.128 fgsch 947: fprintf(stderr,
948: "You must specify a subsystem to invoke.\n");
1.85 djm 949: usage();
950: }
1.31 markus 951: } else {
1.128 fgsch 952: /* A command has been specified. Store it into the buffer. */
953: for (i = 0; i < ac; i++) {
954: if (i)
1.31 markus 955: buffer_append(&command, " ", 1);
956: buffer_append(&command, av[i], strlen(av[i]));
957: }
958: }
959:
960: /* Cannot fork to background if no command. */
1.316 djm 961: if (fork_after_authentication_flag && buffer_len(&command) == 0 &&
962: !no_shell_flag)
963: fatal("Cannot fork into background without a command "
964: "to execute.");
1.31 markus 965:
1.101 markus 966: /*
967: * Initialize "log" output. Since we are the client all output
1.375 dtucker 968: * goes to stderr unless otherwise specified by -y or -E.
1.101 markus 969: */
1.375 dtucker 970: if (use_syslog && logfile != NULL)
971: fatal("Can't specify both -y and -E");
1.422 dtucker 972: if (logfile != NULL)
1.375 dtucker 973: log_redirect_stderr_to(logfile);
1.325 markus 974: log_init(argv0,
1.452 dtucker 975: options.log_level == SYSLOG_LEVEL_NOT_SET ?
976: SYSLOG_LEVEL_INFO : options.log_level,
977: options.log_facility == SYSLOG_FACILITY_NOT_SET ?
978: SYSLOG_FACILITY_USER : options.log_facility,
979: !use_syslog);
1.375 dtucker 980:
981: if (debug_flag)
1.402 markus 982: logit("%s, %s", SSH_VERSION,
983: #ifdef WITH_OPENSSL
984: SSLeay_version(SSLEAY_VERSION)
985: #else
986: "without OpenSSL"
987: #endif
988: );
1.31 markus 989:
1.400 djm 990: /* Parse the configuration files */
1.408 djm 991: process_config_files(host_arg, pw, 0);
1.400 djm 992:
993: /* Hostname canonicalisation needs a few options filled. */
994: fill_default_options_for_canonicalization(&options);
995:
996: /* If the user has replaced the hostname then take it into use now */
997: if (options.hostname != NULL) {
998: /* NB. Please keep in sync with readconf.c:match_cfg_line() */
999: cp = percent_expand(options.hostname,
1000: "h", host, (char *)NULL);
1001: free(host);
1002: host = cp;
1.408 djm 1003: free(options.hostname);
1004: options.hostname = xstrdup(host);
1.400 djm 1005: }
1006:
1007: /* If canonicalization requested then try to apply it */
1008: lowercase(host);
1009: if (options.canonicalize_hostname != SSH_CANONICALISE_NO)
1010: addrs = resolve_canonicalize(&host, options.port);
1011:
1.139 markus 1012: /*
1.401 djm 1013: * If CanonicalizePermittedCNAMEs have been specified but
1014: * other canonicalization did not happen (by not being requested
1015: * or by failing with fallback) then the hostname may still be changed
1016: * as a result of CNAME following.
1017: *
1018: * Try to resolve the bare hostname name using the system resolver's
1019: * usual search rules and then apply the CNAME follow rules.
1020: *
1021: * Skip the lookup if a ProxyCommand is being used unless the user
1022: * has specifically requested canonicalisation for this case via
1023: * CanonicalizeHostname=always
1.139 markus 1024: */
1.443 djm 1025: direct = option_clear_or_none(options.proxy_command) &&
1026: options.jump_host == NULL;
1027: if (addrs == NULL && options.num_permitted_cnames != 0 && (direct ||
1028: options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) {
1.403 djm 1029: if ((addrs = resolve_host(host, options.port,
1030: option_clear_or_none(options.proxy_command),
1031: cname, sizeof(cname))) == NULL) {
1032: /* Don't fatal proxied host names not in the DNS */
1033: if (option_clear_or_none(options.proxy_command))
1034: cleanup_exit(255); /* logged in resolve_host */
1035: } else
1.443 djm 1036: check_follow_cname(direct, &host, cname);
1.400 djm 1037: }
1.139 markus 1038:
1.400 djm 1039: /*
1.408 djm 1040: * If canonicalisation is enabled then re-parse the configuration
1041: * files as new stanzas may match.
1.400 djm 1042: */
1.408 djm 1043: if (options.canonicalize_hostname != 0) {
1044: debug("Re-reading configuration after hostname "
1045: "canonicalisation");
1046: free(options.hostname);
1047: options.hostname = xstrdup(host);
1048: process_config_files(host_arg, pw, 1);
1049: /*
1050: * Address resolution happens early with canonicalisation
1051: * enabled and the port number may have changed since, so
1052: * reset it in address list
1053: */
1054: if (addrs != NULL && options.port > 0)
1055: set_addrinfo_port(addrs, options.port);
1.139 markus 1056: }
1.31 markus 1057:
1058: /* Fill configuration defaults. */
1059: fill_default_options(&options);
1.443 djm 1060:
1061: /*
1062: * If ProxyJump option specified, then construct a ProxyCommand now.
1063: */
1064: if (options.jump_host != NULL) {
1065: char port_s[8];
1066:
1067: /* Consistency check */
1068: if (options.proxy_command != NULL)
1069: fatal("inconsistent options: ProxyCommand+ProxyJump");
1070: /* Never use FD passing for ProxyJump */
1071: options.proxy_use_fdpass = 0;
1072: snprintf(port_s, sizeof(port_s), "%d", options.jump_port);
1073: xasprintf(&options.proxy_command,
1.450 djm 1074: "ssh%s%s%s%s%s%s%s%s%s%.*s -W '[%%h]:%%p' %s",
1.443 djm 1075: /* Optional "-l user" argument if jump_user set */
1076: options.jump_user == NULL ? "" : " -l ",
1077: options.jump_user == NULL ? "" : options.jump_user,
1078: /* Optional "-p port" argument if jump_port set */
1079: options.jump_port <= 0 ? "" : " -p ",
1080: options.jump_port <= 0 ? "" : port_s,
1081: /* Optional additional jump hosts ",..." */
1082: options.jump_extra == NULL ? "" : " -J ",
1083: options.jump_extra == NULL ? "" : options.jump_extra,
1084: /* Optional "-F" argumment if -F specified */
1085: config == NULL ? "" : " -F ",
1086: config == NULL ? "" : config,
1087: /* Optional "-v" arguments if -v set */
1088: debug_flag ? " -" : "",
1089: debug_flag, "vvv",
1090: /* Mandatory hostname */
1091: options.jump_host);
1092: debug("Setting implicit ProxyCommand from ProxyJump: %s",
1093: options.proxy_command);
1094: }
1.31 markus 1095:
1.400 djm 1096: if (options.port == 0)
1097: options.port = default_ssh_port();
1.196 djm 1098: channel_set_af(options.address_family);
1099:
1.383 djm 1100: /* Tidy and check options */
1101: if (options.host_key_alias != NULL)
1102: lowercase(options.host_key_alias);
1103: if (options.proxy_command != NULL &&
1104: strcmp(options.proxy_command, "-") == 0 &&
1105: options.proxy_use_fdpass)
1106: fatal("ProxyCommand=- and ProxyUseFDPass are incompatible");
1.415 djm 1107: if (options.control_persist &&
1108: options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) {
1109: debug("UpdateHostKeys=ask is incompatible with ControlPersist; "
1110: "disabling");
1111: options.update_hostkeys = 0;
1112: }
1.430 djm 1113: if (options.connection_attempts <= 0)
1114: fatal("Invalid number of ConnectionAttempts");
1115:
1.388 djm 1116: if (original_effective_uid != 0)
1117: options.use_privileged_port = 0;
1.383 djm 1118:
1.31 markus 1119: /* reinit */
1.452 dtucker 1120: log_init(argv0, options.log_level, options.log_facility, !use_syslog);
1.370 djm 1121:
1122: if (options.request_tty == REQUEST_TTY_YES ||
1123: options.request_tty == REQUEST_TTY_FORCE)
1124: tty_flag = 1;
1125:
1126: /* Allocate a tty by default if no command specified. */
1127: if (buffer_len(&command) == 0)
1128: tty_flag = options.request_tty != REQUEST_TTY_NO;
1129:
1130: /* Force no tty */
1.447 markus 1131: if (options.request_tty == REQUEST_TTY_NO ||
1132: (muxclient_command && muxclient_command != SSHMUX_COMMAND_PROXY))
1.370 djm 1133: tty_flag = 0;
1134: /* Do not allocate a tty if stdin is not a tty. */
1135: if ((!isatty(fileno(stdin)) || stdin_null_flag) &&
1136: options.request_tty != REQUEST_TTY_FORCE) {
1137: if (tty_flag)
1138: logit("Pseudo-terminal will not be allocated because "
1139: "stdin is not a terminal.");
1140: tty_flag = 0;
1141: }
1.31 markus 1142:
1143: if (options.user == NULL)
1144: options.user = xstrdup(pw->pw_name);
1.343 djm 1145:
1.358 djm 1146: if (gethostname(thishost, sizeof(thishost)) == -1)
1147: fatal("gethostname: %s", strerror(errno));
1148: strlcpy(shorthost, thishost, sizeof(shorthost));
1149: shorthost[strcspn(thishost, ".")] = '\0';
1150: snprintf(portstr, sizeof(portstr), "%d", options.port);
1.423 djm 1151: snprintf(uidstr, sizeof(uidstr), "%d", pw->pw_uid);
1.358 djm 1152:
1.405 djm 1153: if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL ||
1154: ssh_digest_update(md, thishost, strlen(thishost)) < 0 ||
1155: ssh_digest_update(md, host, strlen(host)) < 0 ||
1156: ssh_digest_update(md, portstr, strlen(portstr)) < 0 ||
1157: ssh_digest_update(md, options.user, strlen(options.user)) < 0 ||
1158: ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0)
1159: fatal("%s: mux digest failed", __func__);
1160: ssh_digest_free(md);
1161: conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1));
1162:
1.317 dtucker 1163: if (options.local_command != NULL) {
1164: debug3("expanding LocalCommand: %s", options.local_command);
1165: cp = options.local_command;
1.405 djm 1166: options.local_command = percent_expand(cp,
1167: "C", conn_hash_hex,
1168: "L", shorthost,
1169: "d", pw->pw_dir,
1170: "h", host,
1171: "l", thishost,
1172: "n", host_arg,
1173: "p", portstr,
1174: "r", options.user,
1175: "u", pw->pw_name,
1.358 djm 1176: (char *)NULL);
1.317 dtucker 1177: debug3("expanded LocalCommand: %s", options.local_command);
1.378 djm 1178: free(cp);
1.304 dtucker 1179: }
1.31 markus 1180:
1.214 djm 1181: if (options.control_path != NULL) {
1.241 djm 1182: cp = tilde_expand_filename(options.control_path,
1183: original_real_uid);
1.378 djm 1184: free(options.control_path);
1.405 djm 1185: options.control_path = percent_expand(cp,
1186: "C", conn_hash_hex,
1187: "L", shorthost,
1188: "h", host,
1189: "l", thishost,
1190: "n", host_arg,
1191: "p", portstr,
1192: "r", options.user,
1193: "u", pw->pw_name,
1.423 djm 1194: "i", uidstr,
1.358 djm 1195: (char *)NULL);
1.378 djm 1196: free(cp);
1.214 djm 1197: }
1.405 djm 1198: free(conn_hash_hex);
1.408 djm 1199:
1200: if (config_test) {
1201: dump_client_config(&options, host);
1202: exit(0);
1203: }
1.405 djm 1204:
1.312 djm 1205: if (muxclient_command != 0 && options.control_path == NULL)
1.240 djm 1206: fatal("No ControlPath specified for \"-O\" command");
1.447 markus 1207: if (options.control_path != NULL) {
1208: int sock;
1209: if ((sock = muxclient(options.control_path)) >= 0) {
1210: packet_set_connection(sock, sock);
1211: ssh = active_state; /* XXX */
1212: enable_compat20(); /* XXX */
1213: packet_set_mux();
1214: goto skip_connect;
1215: }
1216: }
1.401 djm 1217:
1218: /*
1219: * If hostname canonicalisation was not enabled, then we may not
1220: * have yet resolved the hostname. Do so now.
1221: */
1222: if (addrs == NULL && options.proxy_command == NULL) {
1.421 djm 1223: debug2("resolving \"%s\" port %d", host, options.port);
1.401 djm 1224: if ((addrs = resolve_host(host, options.port, 1,
1225: cname, sizeof(cname))) == NULL)
1226: cleanup_exit(255); /* resolve_host logs the error */
1227: }
1.214 djm 1228:
1.303 djm 1229: timeout_ms = options.connection_timeout * 1000;
1230:
1.77 markus 1231: /* Open a connection to the remote host. */
1.385 djm 1232: if (ssh_connect(host, addrs, &hostaddr, options.port,
1233: options.address_family, options.connection_attempts,
1234: &timeout_ms, options.tcp_keep_alive,
1.388 djm 1235: options.use_privileged_port) != 0)
1.257 dtucker 1236: exit(255);
1.31 markus 1237:
1.391 djm 1238: if (addrs != NULL)
1239: freeaddrinfo(addrs);
1240:
1.385 djm 1241: packet_set_timeout(options.server_alive_interval,
1242: options.server_alive_count_max);
1243:
1.437 djm 1244: ssh = active_state; /* XXX */
1245:
1.303 djm 1246: if (timeout_ms > 0)
1247: debug3("timeout: %d ms remain after connect", timeout_ms);
1248:
1.33 markus 1249: /*
1250: * If we successfully made the connection, load the host private key
1251: * in case we will need it later for combined rsa-rhosts
1252: * authentication. This must be done before releasing extra
1253: * privileges, because the file is only readable by root.
1.174 markus 1254: * If we cannot access the private keys, load the public keys
1255: * instead and try to execute the ssh-keysign helper instead.
1.33 markus 1256: */
1.112 markus 1257: sensitive_data.nkeys = 0;
1258: sensitive_data.keys = NULL;
1.173 markus 1259: sensitive_data.external_keysign = 0;
1.178 markus 1260: if (options.rhosts_rsa_authentication ||
1261: options.hostbased_authentication) {
1.397 djm 1262: sensitive_data.nkeys = 9;
1.274 deraadt 1263: sensitive_data.keys = xcalloc(sensitive_data.nkeys,
1.180 deraadt 1264: sizeof(Key));
1.177 markus 1265:
1266: PRIV_START;
1.411 djm 1267: sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA,
1.349 djm 1268: _PATH_HOST_ECDSA_KEY_FILE, "", NULL);
1.411 djm 1269: sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519,
1270: _PATH_HOST_ED25519_KEY_FILE, "", NULL);
1.349 djm 1271: sensitive_data.keys[3] = key_load_private_cert(KEY_RSA,
1.345 djm 1272: _PATH_HOST_RSA_KEY_FILE, "", NULL);
1.411 djm 1273: sensitive_data.keys[4] = key_load_private_cert(KEY_DSA,
1274: _PATH_HOST_DSA_KEY_FILE, "", NULL);
1275: sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA,
1.349 djm 1276: _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL);
1.411 djm 1277: sensitive_data.keys[6] = key_load_private_type(KEY_ED25519,
1278: _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL);
1.397 djm 1279: sensitive_data.keys[7] = key_load_private_type(KEY_RSA,
1.276 dtucker 1280: _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL);
1.411 djm 1281: sensitive_data.keys[8] = key_load_private_type(KEY_DSA,
1282: _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL);
1.177 markus 1283: PRIV_END;
1.173 markus 1284:
1.181 markus 1285: if (options.hostbased_authentication == 1 &&
1286: sensitive_data.keys[0] == NULL &&
1.349 djm 1287: sensitive_data.keys[5] == NULL &&
1.396 markus 1288: sensitive_data.keys[6] == NULL &&
1.397 djm 1289: sensitive_data.keys[7] == NULL &&
1290: sensitive_data.keys[8] == NULL) {
1.345 djm 1291: sensitive_data.keys[1] = key_load_cert(
1.411 djm 1292: _PATH_HOST_ECDSA_KEY_FILE);
1.345 djm 1293: sensitive_data.keys[2] = key_load_cert(
1.411 djm 1294: _PATH_HOST_ED25519_KEY_FILE);
1.349 djm 1295: sensitive_data.keys[3] = key_load_cert(
1.345 djm 1296: _PATH_HOST_RSA_KEY_FILE);
1.397 djm 1297: sensitive_data.keys[4] = key_load_cert(
1.411 djm 1298: _PATH_HOST_DSA_KEY_FILE);
1.397 djm 1299: sensitive_data.keys[5] = key_load_public(
1.411 djm 1300: _PATH_HOST_ECDSA_KEY_FILE, NULL);
1.397 djm 1301: sensitive_data.keys[6] = key_load_public(
1.411 djm 1302: _PATH_HOST_ED25519_KEY_FILE, NULL);
1.397 djm 1303: sensitive_data.keys[7] = key_load_public(
1.173 markus 1304: _PATH_HOST_RSA_KEY_FILE, NULL);
1.397 djm 1305: sensitive_data.keys[8] = key_load_public(
1.411 djm 1306: _PATH_HOST_DSA_KEY_FILE, NULL);
1.173 markus 1307: sensitive_data.external_keysign = 1;
1308: }
1.31 markus 1309: }
1.33 markus 1310: /*
1311: * Get rid of any extra privileges that we may have. We will no
1312: * longer need them. Also, extra privileges could make it very hard
1313: * to read identity files and other non-world-readable files from the
1314: * user's home directory if it happens to be on a NFS volume where
1315: * root is mapped to nobody.
1316: */
1.225 dtucker 1317: if (original_effective_uid == 0) {
1318: PRIV_START;
1319: permanently_set_uid(pw);
1320: }
1.31 markus 1321:
1.33 markus 1322: /*
1323: * Now that we are back to our own permissions, create ~/.ssh
1.254 djm 1324: * directory if it doesn't already exist.
1.33 markus 1325: */
1.367 djm 1326: if (config == NULL) {
1327: r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir,
1328: strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR);
1329: if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0)
1330: if (mkdir(buf, 0700) < 0)
1331: error("Could not create directory '%.200s'.",
1332: buf);
1333: }
1.31 markus 1334:
1.104 markus 1335: /* load options.identity_files */
1336: load_public_identity_files();
1.439 markus 1337:
1338: /* optionally set the SSH_AUTHSOCKET_ENV_NAME varibale */
1.440 markus 1339: if (options.identity_agent &&
1340: strcmp(options.identity_agent, SSH_AUTHSOCKET_ENV_NAME) != 0) {
1.439 markus 1341: if (strcmp(options.identity_agent, "none") == 0) {
1342: unsetenv(SSH_AUTHSOCKET_ENV_NAME);
1343: } else {
1344: p = tilde_expand_filename(options.identity_agent,
1345: original_real_uid);
1346: cp = percent_expand(p, "d", pw->pw_dir,
1347: "u", pw->pw_name, "l", thishost, "h", host,
1348: "r", options.user, (char *)NULL);
1349: setenv(SSH_AUTHSOCKET_ENV_NAME, cp, 1);
1350: free(cp);
1351: free(p);
1352: }
1353: }
1.104 markus 1354:
1355: /* Expand ~ in known host file names. */
1.361 djm 1356: tilde_expand_paths(options.system_hostfiles,
1357: options.num_system_hostfiles);
1358: tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles);
1.149 markus 1359:
1360: signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */
1.352 djm 1361: signal(SIGCHLD, main_sigchld_handler);
1.31 markus 1362:
1.316 djm 1363: /* Log into the remote system. Never returns if the login fails. */
1.303 djm 1364: ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr,
1.355 djm 1365: options.port, pw, timeout_ms);
1.339 djm 1366:
1367: if (packet_connection_is_on_socket()) {
1368: verbose("Authenticated to %s ([%s]:%d).", host,
1.437 djm 1369: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh));
1.339 djm 1370: } else {
1371: verbose("Authenticated to %s (via proxy).", host);
1372: }
1.31 markus 1373:
1.112 markus 1374: /* We no longer need the private host keys. Clear them now. */
1375: if (sensitive_data.nkeys != 0) {
1376: for (i = 0; i < sensitive_data.nkeys; i++) {
1377: if (sensitive_data.keys[i] != NULL) {
1378: /* Destroys contents safely */
1379: debug3("clear hostkey %d", i);
1380: key_free(sensitive_data.keys[i]);
1381: sensitive_data.keys[i] = NULL;
1382: }
1383: }
1.378 djm 1384: free(sensitive_data.keys);
1.134 markus 1385: }
1386: for (i = 0; i < options.num_identity_files; i++) {
1.378 djm 1387: free(options.identity_files[i]);
1388: options.identity_files[i] = NULL;
1.134 markus 1389: if (options.identity_keys[i]) {
1390: key_free(options.identity_keys[i]);
1391: options.identity_keys[i] = NULL;
1392: }
1.112 markus 1393: }
1.426 djm 1394: for (i = 0; i < options.num_certificate_files; i++) {
1395: free(options.certificate_files[i]);
1396: options.certificate_files[i] = NULL;
1397: }
1.31 markus 1398:
1.447 markus 1399: skip_connect:
1.45 markus 1400: exit_status = compat20 ? ssh_session2() : ssh_session();
1401: packet_close();
1.186 djm 1402:
1.312 djm 1403: if (options.control_path != NULL && muxserver_sock != -1)
1.214 djm 1404: unlink(options.control_path);
1405:
1.353 djm 1406: /* Kill ProxyCommand if it is running. */
1407: ssh_kill_proxy_command();
1.186 djm 1408:
1.45 markus 1409: return exit_status;
1410: }
1411:
1.344 djm 1412: static void
1413: control_persist_detach(void)
1414: {
1415: pid_t pid;
1.438 djm 1416: int devnull, keep_stderr;
1.344 djm 1417:
1418: debug("%s: backgrounding master process", __func__);
1419:
1420: /*
1421: * master (current process) into the background, and make the
1422: * foreground process a client of the backgrounded master.
1423: */
1424: switch ((pid = fork())) {
1425: case -1:
1426: fatal("%s: fork: %s", __func__, strerror(errno));
1427: case 0:
1428: /* Child: master process continues mainloop */
1429: break;
1430: default:
1431: /* Parent: set up mux slave to connect to backgrounded master */
1432: debug2("%s: background process is %ld", __func__, (long)pid);
1433: stdin_null_flag = ostdin_null_flag;
1.359 djm 1434: options.request_tty = orequest_tty;
1.344 djm 1435: tty_flag = otty_flag;
1436: close(muxserver_sock);
1437: muxserver_sock = -1;
1.351 markus 1438: options.control_master = SSHCTL_MASTER_NO;
1.344 djm 1439: muxclient(options.control_path);
1440: /* muxclient() doesn't return on success. */
1441: fatal("Failed to connect to new control master");
1442: }
1.346 djm 1443: if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) {
1444: error("%s: open(\"/dev/null\"): %s", __func__,
1445: strerror(errno));
1446: } else {
1.438 djm 1447: keep_stderr = log_is_on_stderr() && debug_flag;
1.346 djm 1448: if (dup2(devnull, STDIN_FILENO) == -1 ||
1.438 djm 1449: dup2(devnull, STDOUT_FILENO) == -1 ||
1450: (!keep_stderr && dup2(devnull, STDERR_FILENO) == -1))
1.346 djm 1451: error("%s: dup2: %s", __func__, strerror(errno));
1452: if (devnull > STDERR_FILENO)
1453: close(devnull);
1454: }
1.381 djm 1455: daemon(1, 1);
1.362 djm 1456: setproctitle("%s [mux]", options.control_path);
1.344 djm 1457: }
1458:
1459: /* Do fork() after authentication. Used by "ssh -f" */
1460: static void
1461: fork_postauth(void)
1462: {
1463: if (need_controlpersist_detach)
1464: control_persist_detach();
1465: debug("forking to background");
1466: fork_after_authentication_flag = 0;
1467: if (daemon(1, 1) < 0)
1468: fatal("daemon() failed: %.200s", strerror(errno));
1469: }
1470:
1.315 djm 1471: /* Callback for remote forward global requests */
1472: static void
1473: ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt)
1474: {
1.406 millert 1475: struct Forward *rfwd = (struct Forward *)ctxt;
1.315 djm 1476:
1.324 djm 1477: /* XXX verbose() on failure? */
1.404 markus 1478: debug("remote forward %s for: listen %s%s%d, connect %s:%d",
1.315 djm 1479: type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure",
1.406 millert 1480: rfwd->listen_path ? rfwd->listen_path :
1481: rfwd->listen_host ? rfwd->listen_host : "",
1482: (rfwd->listen_path || rfwd->listen_host) ? ":" : "",
1483: rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path :
1484: rfwd->connect_host, rfwd->connect_port);
1485: if (rfwd->listen_path == NULL && rfwd->listen_port == 0) {
1.366 markus 1486: if (type == SSH2_MSG_REQUEST_SUCCESS) {
1487: rfwd->allocated_port = packet_get_int();
1488: logit("Allocated port %u for remote forward to %s:%d",
1489: rfwd->allocated_port,
1490: rfwd->connect_host, rfwd->connect_port);
1491: channel_update_permitted_opens(rfwd->handle,
1492: rfwd->allocated_port);
1493: } else {
1494: channel_update_permitted_opens(rfwd->handle, -1);
1495: }
1.324 djm 1496: }
1497:
1.315 djm 1498: if (type == SSH2_MSG_REQUEST_FAILURE) {
1.406 millert 1499: if (options.exit_on_forward_failure) {
1500: if (rfwd->listen_path != NULL)
1501: fatal("Error: remote port forwarding failed "
1502: "for listen path %s", rfwd->listen_path);
1503: else
1504: fatal("Error: remote port forwarding failed "
1505: "for listen port %d", rfwd->listen_port);
1506: } else {
1507: if (rfwd->listen_path != NULL)
1508: logit("Warning: remote port forwarding failed "
1509: "for listen path %s", rfwd->listen_path);
1510: else
1511: logit("Warning: remote port forwarding failed "
1512: "for listen port %d", rfwd->listen_port);
1513: }
1.315 djm 1514: }
1.318 djm 1515: if (++remote_forward_confirms_received == options.num_remote_forwards) {
1.315 djm 1516: debug("All remote forwarding requests processed");
1.344 djm 1517: if (fork_after_authentication_flag)
1518: fork_postauth();
1.318 djm 1519: }
1.315 djm 1520: }
1521:
1.126 itojun 1522: static void
1.331 dtucker 1523: client_cleanup_stdio_fwd(int id, void *arg)
1524: {
1525: debug("stdio forwarding: done");
1526: cleanup_exit(0);
1527: }
1528:
1.368 djm 1529: static void
1.407 djm 1530: ssh_stdio_confirm(int id, int success, void *arg)
1531: {
1532: if (!success)
1533: fatal("stdio forwarding failed");
1534: }
1535:
1536: static void
1.368 djm 1537: ssh_init_stdio_forwarding(void)
1.331 dtucker 1538: {
1539: Channel *c;
1.332 djm 1540: int in, out;
1.331 dtucker 1541:
1.441 dtucker 1542: if (options.stdio_forward_host == NULL)
1.368 djm 1543: return;
1.384 djm 1544: if (!compat20)
1.368 djm 1545: fatal("stdio forwarding require Protocol 2");
1546:
1.441 dtucker 1547: debug3("%s: %s:%d", __func__, options.stdio_forward_host,
1548: options.stdio_forward_port);
1.332 djm 1549:
1.368 djm 1550: if ((in = dup(STDIN_FILENO)) < 0 ||
1551: (out = dup(STDOUT_FILENO)) < 0)
1.332 djm 1552: fatal("channel_connect_stdio_fwd: dup() in/out failed");
1.441 dtucker 1553: if ((c = channel_connect_stdio_fwd(options.stdio_forward_host,
1554: options.stdio_forward_port, in, out)) == NULL)
1.368 djm 1555: fatal("%s: channel_connect_stdio_fwd failed", __func__);
1.331 dtucker 1556: channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0);
1.407 djm 1557: channel_register_open_confirm(c->self, ssh_stdio_confirm, NULL);
1.331 dtucker 1558: }
1559:
1560: static void
1.70 markus 1561: ssh_init_forwarding(void)
1562: {
1.86 markus 1563: int success = 0;
1.70 markus 1564: int i;
1.331 dtucker 1565:
1.70 markus 1566: /* Initiate local TCP/IP port forwardings. */
1567: for (i = 0; i < options.num_local_forwards; i++) {
1.232 djm 1568: debug("Local connections to %.200s:%d forwarded to remote "
1569: "address %.200s:%d",
1.406 millert 1570: (options.local_forwards[i].listen_path != NULL) ?
1571: options.local_forwards[i].listen_path :
1.234 deraadt 1572: (options.local_forwards[i].listen_host == NULL) ?
1.406 millert 1573: (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") :
1.232 djm 1574: options.local_forwards[i].listen_host,
1575: options.local_forwards[i].listen_port,
1.406 millert 1576: (options.local_forwards[i].connect_path != NULL) ?
1577: options.local_forwards[i].connect_path :
1.232 djm 1578: options.local_forwards[i].connect_host,
1579: options.local_forwards[i].connect_port);
1.158 markus 1580: success += channel_setup_local_fwd_listener(
1.406 millert 1581: &options.local_forwards[i], &options.fwd_opts);
1.70 markus 1582: }
1.283 markus 1583: if (i > 0 && success != i && options.exit_on_forward_failure)
1584: fatal("Could not request local forwarding.");
1.86 markus 1585: if (i > 0 && success == 0)
1586: error("Could not request local forwarding.");
1.70 markus 1587:
1588: /* Initiate remote TCP/IP port forwardings. */
1589: for (i = 0; i < options.num_remote_forwards; i++) {
1.232 djm 1590: debug("Remote connections from %.200s:%d forwarded to "
1591: "local address %.200s:%d",
1.406 millert 1592: (options.remote_forwards[i].listen_path != NULL) ?
1593: options.remote_forwards[i].listen_path :
1.248 djm 1594: (options.remote_forwards[i].listen_host == NULL) ?
1.253 djm 1595: "LOCALHOST" : options.remote_forwards[i].listen_host,
1.232 djm 1596: options.remote_forwards[i].listen_port,
1.406 millert 1597: (options.remote_forwards[i].connect_path != NULL) ?
1598: options.remote_forwards[i].connect_path :
1.232 djm 1599: options.remote_forwards[i].connect_host,
1600: options.remote_forwards[i].connect_port);
1.366 markus 1601: options.remote_forwards[i].handle =
1602: channel_request_remote_forwarding(
1.406 millert 1603: &options.remote_forwards[i]);
1.366 markus 1604: if (options.remote_forwards[i].handle < 0) {
1.283 markus 1605: if (options.exit_on_forward_failure)
1606: fatal("Could not request remote forwarding.");
1607: else
1608: logit("Warning: Could not request remote "
1609: "forwarding.");
1.366 markus 1610: } else {
1611: client_register_global_confirm(ssh_confirm_remote_forward,
1612: &options.remote_forwards[i]);
1.283 markus 1613: }
1.70 markus 1614: }
1.301 djm 1615:
1616: /* Initiate tunnel forwarding. */
1617: if (options.tun_open != SSH_TUNMODE_NO) {
1618: if (client_request_tun_fwd(options.tun_open,
1619: options.tun_local, options.tun_remote) == -1) {
1620: if (options.exit_on_forward_failure)
1621: fatal("Could not request tunnel forwarding.");
1622: else
1623: error("Could not request tunnel forwarding.");
1624: }
1625: }
1.70 markus 1626: }
1627:
1.126 itojun 1628: static void
1.70 markus 1629: check_agent_present(void)
1630: {
1.412 djm 1631: int r;
1632:
1.70 markus 1633: if (options.forward_agent) {
1.254 djm 1634: /* Clear agent forwarding if we don't have an agent. */
1.412 djm 1635: if ((r = ssh_get_authentication_socket(NULL)) != 0) {
1.70 markus 1636: options.forward_agent = 0;
1.412 djm 1637: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1638: debug("ssh_get_authentication_socket: %s",
1639: ssh_err(r));
1640: }
1.70 markus 1641: }
1642: }
1643:
1.126 itojun 1644: static int
1.45 markus 1645: ssh_session(void)
1646: {
1647: int type;
1648: int interactive = 0;
1649: int have_tty = 0;
1650: struct winsize ws;
1651: char *cp;
1.243 djm 1652: const char *display;
1.433 djm 1653: char *proto = NULL, *data = NULL;
1.45 markus 1654:
1.31 markus 1655: /* Enable compression if requested. */
1656: if (options.compression) {
1.316 djm 1657: debug("Requesting compression at level %d.",
1658: options.compression_level);
1.31 markus 1659:
1.316 djm 1660: if (options.compression_level < 1 ||
1661: options.compression_level > 9)
1662: fatal("Compression level must be from 1 (fast) to "
1663: "9 (slow, best).");
1.31 markus 1664:
1665: /* Send the request. */
1666: packet_start(SSH_CMSG_REQUEST_COMPRESSION);
1667: packet_put_int(options.compression_level);
1668: packet_send();
1669: packet_write_wait();
1.156 markus 1670: type = packet_read();
1.31 markus 1671: if (type == SSH_SMSG_SUCCESS)
1672: packet_start_compression(options.compression_level);
1673: else if (type == SSH_SMSG_FAILURE)
1.191 itojun 1674: logit("Warning: Remote host refused compression.");
1.31 markus 1675: else
1.316 djm 1676: packet_disconnect("Protocol error waiting for "
1677: "compression response.");
1.31 markus 1678: }
1679: /* Allocate a pseudo tty if appropriate. */
1680: if (tty_flag) {
1681: debug("Requesting pty.");
1682:
1683: /* Start the packet. */
1684: packet_start(SSH_CMSG_REQUEST_PTY);
1685:
1686: /* Store TERM in the packet. There is no limit on the
1687: length of the string. */
1688: cp = getenv("TERM");
1689: if (!cp)
1690: cp = "";
1.124 markus 1691: packet_put_cstring(cp);
1.31 markus 1692:
1693: /* Store window size in the packet. */
1694: if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
1695: memset(&ws, 0, sizeof(ws));
1.269 deraadt 1696: packet_put_int((u_int)ws.ws_row);
1697: packet_put_int((u_int)ws.ws_col);
1698: packet_put_int((u_int)ws.ws_xpixel);
1699: packet_put_int((u_int)ws.ws_ypixel);
1.31 markus 1700:
1701: /* Store tty modes in the packet. */
1.115 stevesk 1702: tty_make_modes(fileno(stdin), NULL);
1.31 markus 1703:
1704: /* Send the packet, and wait for it to leave. */
1705: packet_send();
1706: packet_write_wait();
1707:
1708: /* Read response from the server. */
1.156 markus 1709: type = packet_read();
1.43 markus 1710: if (type == SSH_SMSG_SUCCESS) {
1.31 markus 1711: interactive = 1;
1.45 markus 1712: have_tty = 1;
1.43 markus 1713: } else if (type == SSH_SMSG_FAILURE)
1.316 djm 1714: logit("Warning: Remote host failed or refused to "
1715: "allocate a pseudo tty.");
1.31 markus 1716: else
1.316 djm 1717: packet_disconnect("Protocol error waiting for pty "
1718: "request response.");
1.31 markus 1719: }
1720: /* Request X11 forwarding if enabled and DISPLAY is set. */
1.243 djm 1721: display = getenv("DISPLAY");
1.417 djm 1722: if (display == NULL && options.forward_x11)
1723: debug("X11 forwarding requested but DISPLAY not set");
1.433 djm 1724: if (options.forward_x11 && client_x11_get_proto(display,
1725: options.xauth_location, options.forward_x11_trusted,
1726: options.forward_x11_timeout, &proto, &data) == 0) {
1.50 markus 1727: /* Request forwarding with authentication spoofing. */
1.316 djm 1728: debug("Requesting X11 forwarding with authentication "
1729: "spoofing.");
1.363 djm 1730: x11_request_forwarding_with_spoofing(0, display, proto,
1731: data, 0);
1.31 markus 1732: /* Read response from the server. */
1.156 markus 1733: type = packet_read();
1.31 markus 1734: if (type == SSH_SMSG_SUCCESS) {
1735: interactive = 1;
1.50 markus 1736: } else if (type == SSH_SMSG_FAILURE) {
1.191 itojun 1737: logit("Warning: Remote host denied X11 forwarding.");
1.50 markus 1738: } else {
1.316 djm 1739: packet_disconnect("Protocol error waiting for X11 "
1740: "forwarding");
1.50 markus 1741: }
1.31 markus 1742: }
1743: /* Tell the packet module whether this is an interactive session. */
1.354 djm 1744: packet_set_interactive(interactive,
1745: options.ip_qos_interactive, options.ip_qos_bulk);
1.31 markus 1746:
1747: /* Request authentication agent forwarding if appropriate. */
1.70 markus 1748: check_agent_present();
1749:
1.31 markus 1750: if (options.forward_agent) {
1751: debug("Requesting authentication agent forwarding.");
1752: auth_request_forwarding();
1753:
1754: /* Read response from the server. */
1.156 markus 1755: type = packet_read();
1.155 markus 1756: packet_check_eom();
1.31 markus 1757: if (type != SSH_SMSG_SUCCESS)
1.191 itojun 1758: logit("Warning: Remote host denied authentication agent forwarding.");
1.31 markus 1759: }
1760:
1.70 markus 1761: /* Initiate port forwardings. */
1.368 djm 1762: ssh_init_stdio_forwarding();
1.70 markus 1763: ssh_init_forwarding();
1.305 dtucker 1764:
1765: /* Execute a local command */
1766: if (options.local_command != NULL &&
1767: options.permit_local_command)
1768: ssh_local_cmd(options.local_command);
1.34 markus 1769:
1.318 djm 1770: /*
1771: * If requested and we are not interested in replies to remote
1772: * forwarding requests, then let ssh continue in the background.
1773: */
1.344 djm 1774: if (fork_after_authentication_flag) {
1775: if (options.exit_on_forward_failure &&
1776: options.num_remote_forwards > 0) {
1777: debug("deferring postauth fork until remote forward "
1778: "confirmation received");
1779: } else
1780: fork_postauth();
1.318 djm 1781: }
1.31 markus 1782:
1.33 markus 1783: /*
1784: * If a command was specified on the command line, execute the
1785: * command now. Otherwise request the server to start a shell.
1786: */
1.31 markus 1787: if (buffer_len(&command) > 0) {
1788: int len = buffer_len(&command);
1789: if (len > 900)
1790: len = 900;
1.316 djm 1791: debug("Sending command: %.*s", len,
1792: (u_char *)buffer_ptr(&command));
1.31 markus 1793: packet_start(SSH_CMSG_EXEC_CMD);
1794: packet_put_string(buffer_ptr(&command), buffer_len(&command));
1795: packet_send();
1796: packet_write_wait();
1797: } else {
1798: debug("Requesting shell.");
1799: packet_start(SSH_CMSG_EXEC_SHELL);
1800: packet_send();
1801: packet_write_wait();
1802: }
1803:
1804: /* Enter the interactive session. */
1.119 stevesk 1805: return client_loop(have_tty, tty_flag ?
1806: options.escape_char : SSH_ESCAPECHAR_NONE, 0);
1.89 markus 1807: }
1808:
1.214 djm 1809: /* request pty/x11/agent/tcpfwd/shell for channel */
1810: static void
1.337 djm 1811: ssh_session2_setup(int id, int success, void *arg)
1.214 djm 1812: {
1.215 djm 1813: extern char **environ;
1.243 djm 1814: const char *display;
1815: int interactive = tty_flag;
1.433 djm 1816: char *proto = NULL, *data = NULL;
1.337 djm 1817:
1818: if (!success)
1819: return; /* No need for error message, channels code sens one */
1.215 djm 1820:
1.248 djm 1821: display = getenv("DISPLAY");
1.417 djm 1822: if (display == NULL && options.forward_x11)
1823: debug("X11 forwarding requested but DISPLAY not set");
1.433 djm 1824: if (options.forward_x11 && client_x11_get_proto(display,
1825: options.xauth_location, options.forward_x11_trusted,
1826: options.forward_x11_timeout, &proto, &data) == 0) {
1.50 markus 1827: /* Request forwarding with authentication spoofing. */
1.316 djm 1828: debug("Requesting X11 forwarding with authentication "
1829: "spoofing.");
1.363 djm 1830: x11_request_forwarding_with_spoofing(id, display, proto,
1831: data, 1);
1832: client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN);
1833: /* XXX exit_on_forward_failure */
1.80 markus 1834: interactive = 1;
1.50 markus 1835: }
1836:
1.70 markus 1837: check_agent_present();
1838: if (options.forward_agent) {
1839: debug("Requesting authentication agent forwarding.");
1840: channel_request_start(id, "auth-agent-req@openssh.com", 0);
1841: packet_send();
1.212 djm 1842: }
1.369 dtucker 1843:
1844: /* Tell the packet module whether this is an interactive session. */
1845: packet_set_interactive(interactive,
1846: options.ip_qos_interactive, options.ip_qos_bulk);
1.212 djm 1847:
1.214 djm 1848: client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"),
1.311 djm 1849: NULL, fileno(stdin), &command, environ);
1.45 markus 1850: }
1851:
1.143 markus 1852: /* open new channel for a session */
1.126 itojun 1853: static int
1.143 markus 1854: ssh_session2_open(void)
1.45 markus 1855: {
1.118 markus 1856: Channel *c;
1857: int window, packetmax, in, out, err;
1.60 markus 1858:
1.62 markus 1859: if (stdin_null_flag) {
1.93 itojun 1860: in = open(_PATH_DEVNULL, O_RDONLY);
1.62 markus 1861: } else {
1862: in = dup(STDIN_FILENO);
1863: }
1.60 markus 1864: out = dup(STDOUT_FILENO);
1865: err = dup(STDERR_FILENO);
1.45 markus 1866:
1867: if (in < 0 || out < 0 || err < 0)
1.62 markus 1868: fatal("dup() in/out/err failed");
1.45 markus 1869:
1.69 markus 1870: /* enable nonblocking unless tty */
1871: if (!isatty(in))
1872: set_nonblock(in);
1873: if (!isatty(out))
1874: set_nonblock(out);
1875: if (!isatty(err))
1876: set_nonblock(err);
1877:
1.65 markus 1878: window = CHAN_SES_WINDOW_DEFAULT;
1879: packetmax = CHAN_SES_PACKET_DEFAULT;
1.164 markus 1880: if (tty_flag) {
1881: window >>= 1;
1882: packetmax >>= 1;
1.45 markus 1883: }
1.118 markus 1884: c = channel_new(
1.45 markus 1885: "session", SSH_CHANNEL_OPENING, in, out, err,
1.65 markus 1886: window, packetmax, CHAN_EXTENDED_WRITE,
1.192 markus 1887: "client-session", /*nonblock*/0);
1.45 markus 1888:
1.143 markus 1889: debug3("ssh_session2_open: channel_new: %d", c->self);
1.106 markus 1890:
1.122 markus 1891: channel_send_open(c->self);
1.143 markus 1892: if (!no_shell_flag)
1.310 djm 1893: channel_register_open_confirm(c->self,
1894: ssh_session2_setup, NULL);
1.106 markus 1895:
1.118 markus 1896: return c->self;
1.106 markus 1897: }
1898:
1.126 itojun 1899: static int
1.106 markus 1900: ssh_session2(void)
1901: {
1.143 markus 1902: int id = -1;
1.106 markus 1903:
1904: /* XXX should be pre-session */
1.368 djm 1905: if (!options.control_persist)
1906: ssh_init_stdio_forwarding();
1.106 markus 1907: ssh_init_forwarding();
1908:
1.344 djm 1909: /* Start listening for multiplex clients */
1.447 markus 1910: if (!packet_get_mux())
1911: muxserver_listen();
1.344 djm 1912:
1913: /*
1.368 djm 1914: * If we are in control persist mode and have a working mux listen
1915: * socket, then prepare to background ourselves and have a foreground
1916: * client attach as a control slave.
1917: * NB. we must save copies of the flags that we override for
1.344 djm 1918: * the backgrounding, since we defer attachment of the slave until
1919: * after the connection is fully established (in particular,
1920: * async rfwd replies have been received for ExitOnForwardFailure).
1921: */
1922: if (options.control_persist && muxserver_sock != -1) {
1923: ostdin_null_flag = stdin_null_flag;
1924: ono_shell_flag = no_shell_flag;
1.359 djm 1925: orequest_tty = options.request_tty;
1.344 djm 1926: otty_flag = tty_flag;
1927: stdin_null_flag = 1;
1928: no_shell_flag = 1;
1929: tty_flag = 0;
1930: if (!fork_after_authentication_flag)
1931: need_controlpersist_detach = 1;
1932: fork_after_authentication_flag = 1;
1933: }
1.368 djm 1934: /*
1935: * ControlPersist mux listen socket setup failed, attempt the
1936: * stdio forward setup that we skipped earlier.
1937: */
1938: if (options.control_persist && muxserver_sock == -1)
1939: ssh_init_stdio_forwarding();
1.344 djm 1940:
1.143 markus 1941: if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN))
1942: id = ssh_session2_open();
1.379 djm 1943: else {
1944: packet_set_interactive(
1945: options.control_master == SSHCTL_MASTER_NO,
1946: options.ip_qos_interactive, options.ip_qos_bulk);
1947: }
1.314 djm 1948:
1949: /* If we don't expect to open a new session, then disallow it */
1.319 markus 1950: if (options.control_master == SSHCTL_MASTER_NO &&
1951: (datafellows & SSH_NEW_OPENSSH)) {
1.314 djm 1952: debug("Requesting no-more-sessions@openssh.com");
1953: packet_start(SSH2_MSG_GLOBAL_REQUEST);
1954: packet_put_cstring("no-more-sessions@openssh.com");
1955: packet_put_char(0);
1956: packet_send();
1957: }
1.255 reyk 1958:
1959: /* Execute a local command */
1960: if (options.local_command != NULL &&
1961: options.permit_local_command)
1962: ssh_local_cmd(options.local_command);
1.301 djm 1963:
1.342 djm 1964: /*
1965: * If requested and we are not interested in replies to remote
1966: * forwarding requests, then let ssh continue in the background.
1967: */
1.344 djm 1968: if (fork_after_authentication_flag) {
1969: if (options.exit_on_forward_failure &&
1970: options.num_remote_forwards > 0) {
1971: debug("deferring postauth fork until remote forward "
1972: "confirmation received");
1973: } else
1974: fork_postauth();
1.318 djm 1975: }
1.31 markus 1976:
1.119 stevesk 1977: return client_loop(tty_flag, tty_flag ?
1978: options.escape_char : SSH_ESCAPECHAR_NONE, id);
1.72 markus 1979: }
1980:
1.426 djm 1981: /* Loads all IdentityFile and CertificateFile keys */
1.126 itojun 1982: static void
1.104 markus 1983: load_public_identity_files(void)
1984: {
1.275 djm 1985: char *filename, *cp, thishost[NI_MAXHOST];
1.306 deraadt 1986: char *pwdir = NULL, *pwname = NULL;
1.104 markus 1987: Key *public;
1.275 djm 1988: struct passwd *pw;
1.426 djm 1989: int i;
1990: u_int n_ids, n_certs;
1.335 djm 1991: char *identity_files[SSH_MAX_IDENTITY_FILES];
1992: Key *identity_keys[SSH_MAX_IDENTITY_FILES];
1.426 djm 1993: char *certificate_files[SSH_MAX_CERTIFICATE_FILES];
1994: struct sshkey *certificates[SSH_MAX_CERTIFICATE_FILES];
1.333 markus 1995: #ifdef ENABLE_PKCS11
1.167 markus 1996: Key **keys;
1.333 markus 1997: int nkeys;
1.335 djm 1998: #endif /* PKCS11 */
1.104 markus 1999:
1.426 djm 2000: n_ids = n_certs = 0;
1.398 tedu 2001: memset(identity_files, 0, sizeof(identity_files));
2002: memset(identity_keys, 0, sizeof(identity_keys));
1.426 djm 2003: memset(certificate_files, 0, sizeof(certificate_files));
2004: memset(certificates, 0, sizeof(certificates));
1.335 djm 2005:
2006: #ifdef ENABLE_PKCS11
1.333 markus 2007: if (options.pkcs11_provider != NULL &&
1.167 markus 2008: options.num_identity_files < SSH_MAX_IDENTITY_FILES &&
1.333 markus 2009: (pkcs11_init(!options.batch_mode) == 0) &&
2010: (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL,
2011: &keys)) > 0) {
2012: for (i = 0; i < nkeys; i++) {
1.335 djm 2013: if (n_ids >= SSH_MAX_IDENTITY_FILES) {
2014: key_free(keys[i]);
2015: continue;
2016: }
2017: identity_keys[n_ids] = keys[i];
2018: identity_files[n_ids] =
1.333 markus 2019: xstrdup(options.pkcs11_provider); /* XXX */
1.335 djm 2020: n_ids++;
1.167 markus 2021: }
1.378 djm 2022: free(keys);
1.127 markus 2023: }
1.333 markus 2024: #endif /* ENABLE_PKCS11 */
1.275 djm 2025: if ((pw = getpwuid(original_real_uid)) == NULL)
2026: fatal("load_public_identity_files: getpwuid failed");
1.307 dtucker 2027: pwname = xstrdup(pw->pw_name);
2028: pwdir = xstrdup(pw->pw_dir);
1.275 djm 2029: if (gethostname(thishost, sizeof(thishost)) == -1)
2030: fatal("load_public_identity_files: gethostname: %s",
2031: strerror(errno));
1.335 djm 2032: for (i = 0; i < options.num_identity_files; i++) {
1.373 djm 2033: if (n_ids >= SSH_MAX_IDENTITY_FILES ||
2034: strcasecmp(options.identity_files[i], "none") == 0) {
1.378 djm 2035: free(options.identity_files[i]);
1.426 djm 2036: options.identity_files[i] = NULL;
1.335 djm 2037: continue;
2038: }
1.275 djm 2039: cp = tilde_expand_filename(options.identity_files[i],
1.131 millert 2040: original_real_uid);
1.306 deraadt 2041: filename = percent_expand(cp, "d", pwdir,
2042: "u", pwname, "l", thishost, "h", host,
1.275 djm 2043: "r", options.user, (char *)NULL);
1.378 djm 2044: free(cp);
1.131 millert 2045: public = key_load_public(filename, NULL);
2046: debug("identity file %s type %d", filename,
2047: public ? public->type : -1);
1.378 djm 2048: free(options.identity_files[i]);
1.335 djm 2049: identity_files[n_ids] = filename;
2050: identity_keys[n_ids] = public;
2051:
2052: if (++n_ids >= SSH_MAX_IDENTITY_FILES)
2053: continue;
2054:
1.426 djm 2055: /*
2056: * If no certificates have been explicitly listed then try
2057: * to add the default certificate variant too.
2058: */
2059: if (options.num_certificate_files != 0)
2060: continue;
1.335 djm 2061: xasprintf(&cp, "%s-cert", filename);
2062: public = key_load_public(cp, NULL);
2063: debug("identity file %s type %d", cp,
2064: public ? public->type : -1);
2065: if (public == NULL) {
1.378 djm 2066: free(cp);
1.335 djm 2067: continue;
2068: }
2069: if (!key_is_cert(public)) {
2070: debug("%s: key %s type %s is not a certificate",
2071: __func__, cp, key_type(public));
2072: key_free(public);
1.378 djm 2073: free(cp);
1.335 djm 2074: continue;
2075: }
1.448 djm 2076: /* NB. leave filename pointing to private key */
2077: identity_files[n_ids] = xstrdup(filename);
1.335 djm 2078: identity_keys[n_ids] = public;
2079: n_ids++;
2080: }
1.426 djm 2081:
2082: if (options.num_certificate_files > SSH_MAX_CERTIFICATE_FILES)
2083: fatal("%s: too many certificates", __func__);
2084: for (i = 0; i < options.num_certificate_files; i++) {
2085: cp = tilde_expand_filename(options.certificate_files[i],
2086: original_real_uid);
2087: filename = percent_expand(cp, "d", pwdir,
2088: "u", pwname, "l", thishost, "h", host,
2089: "r", options.user, (char *)NULL);
2090: free(cp);
2091:
2092: public = key_load_public(filename, NULL);
2093: debug("certificate file %s type %d", filename,
2094: public ? public->type : -1);
2095: free(options.certificate_files[i]);
2096: options.certificate_files[i] = NULL;
2097: if (public == NULL) {
2098: free(filename);
2099: continue;
2100: }
2101: if (!key_is_cert(public)) {
2102: debug("%s: key %s type %s is not a certificate",
2103: __func__, filename, key_type(public));
2104: key_free(public);
2105: free(filename);
2106: continue;
2107: }
2108: certificate_files[n_certs] = filename;
2109: certificates[n_certs] = public;
2110: ++n_certs;
2111: }
2112:
1.335 djm 2113: options.num_identity_files = n_ids;
2114: memcpy(options.identity_files, identity_files, sizeof(identity_files));
2115: memcpy(options.identity_keys, identity_keys, sizeof(identity_keys));
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));
1.335 djm 2121:
1.398 tedu 2122: explicit_bzero(pwname, strlen(pwname));
1.378 djm 2123: free(pwname);
1.398 tedu 2124: explicit_bzero(pwdir, strlen(pwdir));
1.378 djm 2125: free(pwdir);
1.214 djm 2126: }
1.352 djm 2127:
2128: static void
2129: main_sigchld_handler(int sig)
2130: {
2131: int save_errno = errno;
2132: pid_t pid;
2133: int status;
2134:
2135: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
2136: (pid < 0 && errno == EINTR))
2137: ;
2138:
2139: signal(sig, main_sigchld_handler);
2140: errno = save_errno;
2141: }