Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1 | /* $OpenBSD: ssh.c,v 1.416 2015/03/03 06:48:58 djm Exp $ */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2 | /* |
| 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 | * |
| 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. |
| 17 | * Copyright (c) 2000, 2001, 2002, 2003 Markus Friedl. All rights reserved. |
| 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. |
| 41 | */ |
| 42 | |
| 43 | #include "includes.h" |
| 44 | |
| 45 | #include <sys/types.h> |
| 46 | #ifdef HAVE_SYS_STAT_H |
| 47 | # include <sys/stat.h> |
| 48 | #endif |
| 49 | #include <sys/resource.h> |
| 50 | #include <sys/ioctl.h> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 51 | #include <sys/socket.h> |
| 52 | #include <sys/wait.h> |
| 53 | |
| 54 | #include <ctype.h> |
| 55 | #include <errno.h> |
| 56 | #include <fcntl.h> |
| 57 | #include <netdb.h> |
| 58 | #ifdef HAVE_PATHS_H |
| 59 | #include <paths.h> |
| 60 | #endif |
| 61 | #include <pwd.h> |
| 62 | #include <signal.h> |
| 63 | #include <stdarg.h> |
| 64 | #include <stddef.h> |
| 65 | #include <stdio.h> |
| 66 | #include <stdlib.h> |
| 67 | #include <string.h> |
| 68 | #include <unistd.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 69 | #include <limits.h> |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 70 | |
| 71 | #include <netinet/in.h> |
| 72 | #include <arpa/inet.h> |
| 73 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 74 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 75 | #include <openssl/evp.h> |
| 76 | #include <openssl/err.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 77 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 78 | #include "openbsd-compat/openssl-compat.h" |
| 79 | #include "openbsd-compat/sys-queue.h" |
| 80 | |
| 81 | #include "xmalloc.h" |
| 82 | #include "ssh.h" |
| 83 | #include "ssh1.h" |
| 84 | #include "ssh2.h" |
| 85 | #include "canohost.h" |
| 86 | #include "compat.h" |
| 87 | #include "cipher.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 88 | #include "digest.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 89 | #include "packet.h" |
| 90 | #include "buffer.h" |
| 91 | #include "channels.h" |
| 92 | #include "key.h" |
| 93 | #include "authfd.h" |
| 94 | #include "authfile.h" |
| 95 | #include "pathnames.h" |
| 96 | #include "dispatch.h" |
| 97 | #include "clientloop.h" |
| 98 | #include "log.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 99 | #include "misc.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 100 | #include "readconf.h" |
| 101 | #include "sshconnect.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 102 | #include "kex.h" |
| 103 | #include "mac.h" |
| 104 | #include "sshpty.h" |
| 105 | #include "match.h" |
| 106 | #include "msg.h" |
| 107 | #include "uidswap.h" |
| 108 | #include "roaming.h" |
| 109 | #include "version.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 110 | #include "ssherr.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 111 | |
| 112 | #ifdef ENABLE_PKCS11 |
| 113 | #include "ssh-pkcs11.h" |
| 114 | #endif |
| 115 | |
| 116 | extern char *__progname; |
| 117 | |
| 118 | /* Saves a copy of argv for setproctitle emulation */ |
| 119 | #ifndef HAVE_SETPROCTITLE |
| 120 | static char **saved_av; |
| 121 | #endif |
| 122 | |
| 123 | /* Flag indicating whether debug mode is on. May be set on the command line. */ |
| 124 | int debug_flag = 0; |
| 125 | |
| 126 | /* Flag indicating whether a tty should be requested */ |
| 127 | int tty_flag = 0; |
| 128 | |
| 129 | /* don't exec a shell */ |
| 130 | int no_shell_flag = 0; |
| 131 | |
| 132 | /* |
| 133 | * Flag indicating that nothing should be read from stdin. This can be set |
| 134 | * on the command line. |
| 135 | */ |
| 136 | int stdin_null_flag = 0; |
| 137 | |
| 138 | /* |
| 139 | * Flag indicating that the current process should be backgrounded and |
| 140 | * a new slave launched in the foreground for ControlPersist. |
| 141 | */ |
| 142 | int need_controlpersist_detach = 0; |
| 143 | |
| 144 | /* Copies of flags for ControlPersist foreground slave */ |
| 145 | int ostdin_null_flag, ono_shell_flag, otty_flag, orequest_tty; |
| 146 | |
| 147 | /* |
| 148 | * Flag indicating that ssh should fork after authentication. This is useful |
| 149 | * so that the passphrase can be entered manually, and then ssh goes to the |
| 150 | * background. |
| 151 | */ |
| 152 | int fork_after_authentication_flag = 0; |
| 153 | |
| 154 | /* forward stdio to remote host and port */ |
| 155 | char *stdio_forward_host = NULL; |
| 156 | int stdio_forward_port = 0; |
| 157 | |
| 158 | /* |
| 159 | * General data structure for command line options and options configurable |
| 160 | * in configuration files. See readconf.h. |
| 161 | */ |
| 162 | Options options; |
| 163 | |
| 164 | /* optional user configfile */ |
| 165 | char *config = NULL; |
| 166 | |
| 167 | /* |
| 168 | * Name of the host we are connecting to. This is the name given on the |
| 169 | * command line, or the HostName specified for the user-supplied name in a |
| 170 | * configuration file. |
| 171 | */ |
| 172 | char *host; |
| 173 | |
| 174 | /* socket address the host resolves to */ |
| 175 | struct sockaddr_storage hostaddr; |
| 176 | |
| 177 | /* Private host keys. */ |
| 178 | Sensitive sensitive_data; |
| 179 | |
| 180 | /* Original real UID. */ |
| 181 | uid_t original_real_uid; |
| 182 | uid_t original_effective_uid; |
| 183 | |
| 184 | /* command to be executed */ |
| 185 | Buffer command; |
| 186 | |
| 187 | /* Should we execute a command or invoke a subsystem? */ |
| 188 | int subsystem_flag = 0; |
| 189 | |
| 190 | /* # of replies received for global requests */ |
| 191 | static int remote_forward_confirms_received = 0; |
| 192 | |
| 193 | /* mux.c */ |
| 194 | extern int muxserver_sock; |
| 195 | extern u_int muxclient_command; |
| 196 | |
| 197 | /* Prints a help message to the user. This function never returns. */ |
| 198 | |
| 199 | static void |
| 200 | usage(void) |
| 201 | { |
| 202 | fprintf(stderr, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 203 | "usage: ssh [-1246AaCfGgKkMNnqsTtVvXxYy] [-b bind_address] [-c cipher_spec]\n" |
| 204 | " [-D [bind_address:]port] [-E log_file] [-e escape_char]\n" |
| 205 | " [-F configfile] [-I pkcs11] [-i identity_file]\n" |
| 206 | " [-L [bind_address:]port:host:hostport] [-l login_name] [-m mac_spec]\n" |
| 207 | " [-O ctl_cmd] [-o option] [-p port]\n" |
| 208 | " [-Q cipher | cipher-auth | mac | kex | key]\n" |
| 209 | " [-R [bind_address:]port:host:hostport] [-S ctl_path] [-W host:port]\n" |
| 210 | " [-w local_tun[:remote_tun]] [user@]hostname [command]\n" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 211 | ); |
| 212 | exit(255); |
| 213 | } |
| 214 | |
| 215 | static int ssh_session(void); |
| 216 | static int ssh_session2(void); |
| 217 | static void load_public_identity_files(void); |
| 218 | static void main_sigchld_handler(int); |
| 219 | |
| 220 | /* from muxclient.c */ |
| 221 | void muxclient(const char *); |
| 222 | void muxserver_listen(void); |
| 223 | |
| 224 | /* ~/ expand a list of paths. NB. assumes path[n] is heap-allocated. */ |
| 225 | static void |
| 226 | tilde_expand_paths(char **paths, u_int num_paths) |
| 227 | { |
| 228 | u_int i; |
| 229 | char *cp; |
| 230 | |
| 231 | for (i = 0; i < num_paths; i++) { |
| 232 | cp = tilde_expand_filename(paths[i], original_real_uid); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 233 | free(paths[i]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 234 | paths[i] = cp; |
| 235 | } |
| 236 | } |
| 237 | |
| 238 | /* |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 239 | * Attempt to resolve a host name / port to a set of addresses and |
| 240 | * optionally return any CNAMEs encountered along the way. |
| 241 | * Returns NULL on failure. |
| 242 | * NB. this function must operate with a options having undefined members. |
| 243 | */ |
| 244 | static struct addrinfo * |
| 245 | resolve_host(const char *name, int port, int logerr, char *cname, size_t clen) |
| 246 | { |
| 247 | char strport[NI_MAXSERV]; |
| 248 | struct addrinfo hints, *res; |
| 249 | int gaierr, loglevel = SYSLOG_LEVEL_DEBUG1; |
| 250 | |
| 251 | if (port <= 0) |
| 252 | port = default_ssh_port(); |
| 253 | |
| 254 | snprintf(strport, sizeof strport, "%u", port); |
| 255 | memset(&hints, 0, sizeof(hints)); |
| 256 | hints.ai_family = options.address_family == -1 ? |
| 257 | AF_UNSPEC : options.address_family; |
| 258 | hints.ai_socktype = SOCK_STREAM; |
| 259 | if (cname != NULL) |
| 260 | hints.ai_flags = AI_CANONNAME; |
| 261 | if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { |
| 262 | if (logerr || (gaierr != EAI_NONAME && gaierr != EAI_NODATA)) |
| 263 | loglevel = SYSLOG_LEVEL_ERROR; |
| 264 | do_log2(loglevel, "%s: Could not resolve hostname %.100s: %s", |
| 265 | __progname, name, ssh_gai_strerror(gaierr)); |
| 266 | return NULL; |
| 267 | } |
| 268 | if (cname != NULL && res->ai_canonname != NULL) { |
| 269 | if (strlcpy(cname, res->ai_canonname, clen) >= clen) { |
| 270 | error("%s: host \"%s\" cname \"%s\" too long (max %lu)", |
| 271 | __func__, name, res->ai_canonname, (u_long)clen); |
| 272 | if (clen > 0) |
| 273 | *cname = '\0'; |
| 274 | } |
| 275 | } |
| 276 | return res; |
| 277 | } |
| 278 | |
| 279 | /* |
| 280 | * Attempt to resolve a numeric host address / port to a single address. |
| 281 | * Returns a canonical address string. |
| 282 | * Returns NULL on failure. |
| 283 | * NB. this function must operate with a options having undefined members. |
| 284 | */ |
| 285 | static struct addrinfo * |
| 286 | resolve_addr(const char *name, int port, char *caddr, size_t clen) |
| 287 | { |
| 288 | char addr[NI_MAXHOST], strport[NI_MAXSERV]; |
| 289 | struct addrinfo hints, *res; |
| 290 | int gaierr; |
| 291 | |
| 292 | if (port <= 0) |
| 293 | port = default_ssh_port(); |
| 294 | snprintf(strport, sizeof strport, "%u", port); |
| 295 | memset(&hints, 0, sizeof(hints)); |
| 296 | hints.ai_family = options.address_family == -1 ? |
| 297 | AF_UNSPEC : options.address_family; |
| 298 | hints.ai_socktype = SOCK_STREAM; |
| 299 | hints.ai_flags = AI_NUMERICHOST|AI_NUMERICSERV; |
| 300 | if ((gaierr = getaddrinfo(name, strport, &hints, &res)) != 0) { |
| 301 | debug2("%s: could not resolve name %.100s as address: %s", |
| 302 | __func__, name, ssh_gai_strerror(gaierr)); |
| 303 | return NULL; |
| 304 | } |
| 305 | if (res == NULL) { |
| 306 | debug("%s: getaddrinfo %.100s returned no addresses", |
| 307 | __func__, name); |
| 308 | return NULL; |
| 309 | } |
| 310 | if (res->ai_next != NULL) { |
| 311 | debug("%s: getaddrinfo %.100s returned multiple addresses", |
| 312 | __func__, name); |
| 313 | goto fail; |
| 314 | } |
| 315 | if ((gaierr = getnameinfo(res->ai_addr, res->ai_addrlen, |
| 316 | addr, sizeof(addr), NULL, 0, NI_NUMERICHOST)) != 0) { |
| 317 | debug("%s: Could not format address for name %.100s: %s", |
| 318 | __func__, name, ssh_gai_strerror(gaierr)); |
| 319 | goto fail; |
| 320 | } |
| 321 | if (strlcpy(caddr, addr, clen) >= clen) { |
| 322 | error("%s: host \"%s\" addr \"%s\" too long (max %lu)", |
| 323 | __func__, name, addr, (u_long)clen); |
| 324 | if (clen > 0) |
| 325 | *caddr = '\0'; |
| 326 | fail: |
| 327 | freeaddrinfo(res); |
| 328 | return NULL; |
| 329 | } |
| 330 | return res; |
| 331 | } |
| 332 | |
| 333 | /* |
| 334 | * Check whether the cname is a permitted replacement for the hostname |
| 335 | * and perform the replacement if it is. |
| 336 | * NB. this function must operate with a options having undefined members. |
| 337 | */ |
| 338 | static int |
| 339 | check_follow_cname(char **namep, const char *cname) |
| 340 | { |
| 341 | int i; |
| 342 | struct allowed_cname *rule; |
| 343 | |
| 344 | if (*cname == '\0' || options.num_permitted_cnames == 0 || |
| 345 | strcmp(*namep, cname) == 0) |
| 346 | return 0; |
| 347 | if (options.canonicalize_hostname == SSH_CANONICALISE_NO) |
| 348 | return 0; |
| 349 | /* |
| 350 | * Don't attempt to canonicalize names that will be interpreted by |
| 351 | * a proxy unless the user specifically requests so. |
| 352 | */ |
| 353 | if (!option_clear_or_none(options.proxy_command) && |
| 354 | options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) |
| 355 | return 0; |
| 356 | debug3("%s: check \"%s\" CNAME \"%s\"", __func__, *namep, cname); |
| 357 | for (i = 0; i < options.num_permitted_cnames; i++) { |
| 358 | rule = options.permitted_cnames + i; |
| 359 | if (match_pattern_list(*namep, rule->source_list, |
| 360 | strlen(rule->source_list), 1) != 1 || |
| 361 | match_pattern_list(cname, rule->target_list, |
| 362 | strlen(rule->target_list), 1) != 1) |
| 363 | continue; |
| 364 | verbose("Canonicalized DNS aliased hostname " |
| 365 | "\"%s\" => \"%s\"", *namep, cname); |
| 366 | free(*namep); |
| 367 | *namep = xstrdup(cname); |
| 368 | return 1; |
| 369 | } |
| 370 | return 0; |
| 371 | } |
| 372 | |
| 373 | /* |
| 374 | * Attempt to resolve the supplied hostname after applying the user's |
| 375 | * canonicalization rules. Returns the address list for the host or NULL |
| 376 | * if no name was found after canonicalization. |
| 377 | * NB. this function must operate with a options having undefined members. |
| 378 | */ |
| 379 | static struct addrinfo * |
| 380 | resolve_canonicalize(char **hostp, int port) |
| 381 | { |
| 382 | int i, ndots; |
| 383 | char *cp, *fullhost, newname[NI_MAXHOST]; |
| 384 | struct addrinfo *addrs; |
| 385 | |
| 386 | if (options.canonicalize_hostname == SSH_CANONICALISE_NO) |
| 387 | return NULL; |
| 388 | |
| 389 | /* |
| 390 | * Don't attempt to canonicalize names that will be interpreted by |
| 391 | * a proxy unless the user specifically requests so. |
| 392 | */ |
| 393 | if (!option_clear_or_none(options.proxy_command) && |
| 394 | options.canonicalize_hostname != SSH_CANONICALISE_ALWAYS) |
| 395 | return NULL; |
| 396 | |
| 397 | /* Try numeric hostnames first */ |
| 398 | if ((addrs = resolve_addr(*hostp, port, |
| 399 | newname, sizeof(newname))) != NULL) { |
| 400 | debug2("%s: hostname %.100s is address", __func__, *hostp); |
| 401 | if (strcasecmp(*hostp, newname) != 0) { |
| 402 | debug2("%s: canonicalised address \"%s\" => \"%s\"", |
| 403 | __func__, *hostp, newname); |
| 404 | free(*hostp); |
| 405 | *hostp = xstrdup(newname); |
| 406 | } |
| 407 | return addrs; |
| 408 | } |
| 409 | |
| 410 | /* Don't apply canonicalization to sufficiently-qualified hostnames */ |
| 411 | ndots = 0; |
| 412 | for (cp = *hostp; *cp != '\0'; cp++) { |
| 413 | if (*cp == '.') |
| 414 | ndots++; |
| 415 | } |
| 416 | if (ndots > options.canonicalize_max_dots) { |
| 417 | debug3("%s: not canonicalizing hostname \"%s\" (max dots %d)", |
| 418 | __func__, *hostp, options.canonicalize_max_dots); |
| 419 | return NULL; |
| 420 | } |
| 421 | /* Attempt each supplied suffix */ |
| 422 | for (i = 0; i < options.num_canonical_domains; i++) { |
| 423 | *newname = '\0'; |
| 424 | xasprintf(&fullhost, "%s.%s.", *hostp, |
| 425 | options.canonical_domains[i]); |
| 426 | debug3("%s: attempting \"%s\" => \"%s\"", __func__, |
| 427 | *hostp, fullhost); |
| 428 | if ((addrs = resolve_host(fullhost, port, 0, |
| 429 | newname, sizeof(newname))) == NULL) { |
| 430 | free(fullhost); |
| 431 | continue; |
| 432 | } |
| 433 | /* Remove trailing '.' */ |
| 434 | fullhost[strlen(fullhost) - 1] = '\0'; |
| 435 | /* Follow CNAME if requested */ |
| 436 | if (!check_follow_cname(&fullhost, newname)) { |
| 437 | debug("Canonicalized hostname \"%s\" => \"%s\"", |
| 438 | *hostp, fullhost); |
| 439 | } |
| 440 | free(*hostp); |
| 441 | *hostp = fullhost; |
| 442 | return addrs; |
| 443 | } |
| 444 | if (!options.canonicalize_fallback_local) |
| 445 | fatal("%s: Could not resolve host \"%s\"", __progname, *hostp); |
| 446 | debug2("%s: host %s not found in any suffix", __func__, *hostp); |
| 447 | return NULL; |
| 448 | } |
| 449 | |
| 450 | /* |
| 451 | * Read per-user configuration file. Ignore the system wide config |
| 452 | * file if the user specifies a config file on the command line. |
| 453 | */ |
| 454 | static void |
| 455 | process_config_files(const char *host_arg, struct passwd *pw, int post_canon) |
| 456 | { |
| 457 | char buf[PATH_MAX]; |
| 458 | int r; |
| 459 | |
| 460 | if (config != NULL) { |
| 461 | if (strcasecmp(config, "none") != 0 && |
| 462 | !read_config_file(config, pw, host, host_arg, &options, |
| 463 | SSHCONF_USERCONF | (post_canon ? SSHCONF_POSTCANON : 0))) |
| 464 | fatal("Can't open user config file %.100s: " |
| 465 | "%.100s", config, strerror(errno)); |
| 466 | } else { |
| 467 | r = snprintf(buf, sizeof buf, "%s/%s", pw->pw_dir, |
| 468 | _PATH_SSH_USER_CONFFILE); |
| 469 | if (r > 0 && (size_t)r < sizeof(buf)) |
| 470 | (void)read_config_file(buf, pw, host, host_arg, |
| 471 | &options, SSHCONF_CHECKPERM | SSHCONF_USERCONF | |
| 472 | (post_canon ? SSHCONF_POSTCANON : 0)); |
| 473 | |
| 474 | /* Read systemwide configuration file after user config. */ |
| 475 | (void)read_config_file(_PATH_HOST_CONFIG_FILE, pw, |
| 476 | host, host_arg, &options, |
| 477 | post_canon ? SSHCONF_POSTCANON : 0); |
| 478 | } |
| 479 | } |
| 480 | |
| 481 | /* Rewrite the port number in an addrinfo list of addresses */ |
| 482 | static void |
| 483 | set_addrinfo_port(struct addrinfo *addrs, int port) |
| 484 | { |
| 485 | struct addrinfo *addr; |
| 486 | |
| 487 | for (addr = addrs; addr != NULL; addr = addr->ai_next) { |
| 488 | switch (addr->ai_family) { |
| 489 | case AF_INET: |
| 490 | ((struct sockaddr_in *)addr->ai_addr)-> |
| 491 | sin_port = htons(port); |
| 492 | break; |
| 493 | case AF_INET6: |
| 494 | ((struct sockaddr_in6 *)addr->ai_addr)-> |
| 495 | sin6_port = htons(port); |
| 496 | break; |
| 497 | } |
| 498 | } |
| 499 | } |
| 500 | |
| 501 | /* |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 502 | * Main program for the ssh client. |
| 503 | */ |
| 504 | int |
| 505 | main(int ac, char **av) |
| 506 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 507 | int i, r, opt, exit_status, use_syslog, config_test = 0; |
| 508 | char *p, *cp, *line, *argv0, buf[PATH_MAX], *host_arg, *logfile; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 509 | char thishost[NI_MAXHOST], shorthost[NI_MAXHOST], portstr[NI_MAXSERV]; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 510 | char cname[NI_MAXHOST]; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 511 | struct stat st; |
| 512 | struct passwd *pw; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 513 | int timeout_ms; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 514 | extern int optind, optreset; |
| 515 | extern char *optarg; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 516 | struct Forward fwd; |
| 517 | struct addrinfo *addrs = NULL; |
| 518 | struct ssh_digest_ctx *md; |
| 519 | u_char conn_hash[SSH_DIGEST_MAX_LENGTH]; |
| 520 | char *conn_hash_hex; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 521 | |
| 522 | /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ |
| 523 | sanitise_stdfd(); |
| 524 | |
| 525 | __progname = ssh_get_progname(av[0]); |
| 526 | |
| 527 | #ifndef HAVE_SETPROCTITLE |
| 528 | /* Prepare for later setproctitle emulation */ |
| 529 | /* Save argv so it isn't clobbered by setproctitle() emulation */ |
| 530 | saved_av = xcalloc(ac + 1, sizeof(*saved_av)); |
| 531 | for (i = 0; i < ac; i++) |
| 532 | saved_av[i] = xstrdup(av[i]); |
| 533 | saved_av[i] = NULL; |
| 534 | compat_init_setproctitle(ac, av); |
| 535 | av = saved_av; |
| 536 | #endif |
| 537 | |
| 538 | /* |
| 539 | * Discard other fds that are hanging around. These can cause problem |
| 540 | * with backgrounded ssh processes started by ControlPersist. |
| 541 | */ |
| 542 | closefrom(STDERR_FILENO + 1); |
| 543 | |
| 544 | /* |
| 545 | * Save the original real uid. It will be needed later (uid-swapping |
| 546 | * may clobber the real uid). |
| 547 | */ |
| 548 | original_real_uid = getuid(); |
| 549 | original_effective_uid = geteuid(); |
| 550 | |
| 551 | /* |
| 552 | * Use uid-swapping to give up root privileges for the duration of |
| 553 | * option processing. We will re-instantiate the rights when we are |
| 554 | * ready to create the privileged port, and will permanently drop |
| 555 | * them when the port has been created (actually, when the connection |
| 556 | * has been made, as we may need to create the port several times). |
| 557 | */ |
| 558 | PRIV_END; |
| 559 | |
| 560 | #ifdef HAVE_SETRLIMIT |
| 561 | /* If we are installed setuid root be careful to not drop core. */ |
| 562 | if (original_real_uid != original_effective_uid) { |
| 563 | struct rlimit rlim; |
| 564 | rlim.rlim_cur = rlim.rlim_max = 0; |
| 565 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) |
| 566 | fatal("setrlimit failed: %.100s", strerror(errno)); |
| 567 | } |
| 568 | #endif |
| 569 | /* Get user data. */ |
| 570 | pw = getpwuid(original_real_uid); |
| 571 | if (!pw) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 572 | logit("No user exists for uid %lu", (u_long)original_real_uid); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 573 | exit(255); |
| 574 | } |
| 575 | /* Take a copy of the returned structure. */ |
| 576 | pw = pwcopy(pw); |
| 577 | |
| 578 | /* |
| 579 | * Set our umask to something reasonable, as some files are created |
| 580 | * with the default umask. This will make them world-readable but |
| 581 | * writable only by the owner, which is ok for all files for which we |
| 582 | * don't set the modes explicitly. |
| 583 | */ |
| 584 | umask(022); |
| 585 | |
| 586 | /* |
| 587 | * Initialize option structure to indicate that no values have been |
| 588 | * set. |
| 589 | */ |
| 590 | initialize_options(&options); |
| 591 | |
| 592 | /* Parse command-line arguments. */ |
| 593 | host = NULL; |
| 594 | use_syslog = 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 595 | logfile = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 596 | argv0 = av[0]; |
| 597 | |
| 598 | again: |
| 599 | while ((opt = getopt(ac, av, "1246ab:c:e:fgi:kl:m:no:p:qstvx" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 600 | "ACD:E:F:GI:KL:MNO:PQ:R:S:TVw:W:XYy")) != -1) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 601 | switch (opt) { |
| 602 | case '1': |
| 603 | options.protocol = SSH_PROTO_1; |
| 604 | break; |
| 605 | case '2': |
| 606 | options.protocol = SSH_PROTO_2; |
| 607 | break; |
| 608 | case '4': |
| 609 | options.address_family = AF_INET; |
| 610 | break; |
| 611 | case '6': |
| 612 | options.address_family = AF_INET6; |
| 613 | break; |
| 614 | case 'n': |
| 615 | stdin_null_flag = 1; |
| 616 | break; |
| 617 | case 'f': |
| 618 | fork_after_authentication_flag = 1; |
| 619 | stdin_null_flag = 1; |
| 620 | break; |
| 621 | case 'x': |
| 622 | options.forward_x11 = 0; |
| 623 | break; |
| 624 | case 'X': |
| 625 | options.forward_x11 = 1; |
| 626 | break; |
| 627 | case 'y': |
| 628 | use_syslog = 1; |
| 629 | break; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 630 | case 'E': |
| 631 | logfile = xstrdup(optarg); |
| 632 | break; |
| 633 | case 'G': |
| 634 | config_test = 1; |
| 635 | break; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 636 | case 'Y': |
| 637 | options.forward_x11 = 1; |
| 638 | options.forward_x11_trusted = 1; |
| 639 | break; |
| 640 | case 'g': |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 641 | options.fwd_opts.gateway_ports = 1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 642 | break; |
| 643 | case 'O': |
| 644 | if (stdio_forward_host != NULL) |
| 645 | fatal("Cannot specify multiplexing " |
| 646 | "command with -W"); |
| 647 | else if (muxclient_command != 0) |
| 648 | fatal("Multiplexing command already specified"); |
| 649 | if (strcmp(optarg, "check") == 0) |
| 650 | muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK; |
| 651 | else if (strcmp(optarg, "forward") == 0) |
| 652 | muxclient_command = SSHMUX_COMMAND_FORWARD; |
| 653 | else if (strcmp(optarg, "exit") == 0) |
| 654 | muxclient_command = SSHMUX_COMMAND_TERMINATE; |
| 655 | else if (strcmp(optarg, "stop") == 0) |
| 656 | muxclient_command = SSHMUX_COMMAND_STOP; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 657 | else if (strcmp(optarg, "cancel") == 0) |
| 658 | muxclient_command = SSHMUX_COMMAND_CANCEL_FWD; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 659 | else |
| 660 | fatal("Invalid multiplex command."); |
| 661 | break; |
| 662 | case 'P': /* deprecated */ |
| 663 | options.use_privileged_port = 0; |
| 664 | break; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 665 | case 'Q': |
| 666 | cp = NULL; |
| 667 | if (strcmp(optarg, "cipher") == 0) |
| 668 | cp = cipher_alg_list('\n', 0); |
| 669 | else if (strcmp(optarg, "cipher-auth") == 0) |
| 670 | cp = cipher_alg_list('\n', 1); |
| 671 | else if (strcmp(optarg, "mac") == 0) |
| 672 | cp = mac_alg_list('\n'); |
| 673 | else if (strcmp(optarg, "kex") == 0) |
| 674 | cp = kex_alg_list('\n'); |
| 675 | else if (strcmp(optarg, "key") == 0) |
| 676 | cp = key_alg_list(0, 0); |
| 677 | else if (strcmp(optarg, "key-cert") == 0) |
| 678 | cp = key_alg_list(1, 0); |
| 679 | else if (strcmp(optarg, "key-plain") == 0) |
| 680 | cp = key_alg_list(0, 1); |
| 681 | else if (strcmp(optarg, "protocol-version") == 0) { |
| 682 | #ifdef WITH_SSH1 |
| 683 | cp = xstrdup("1\n2"); |
| 684 | #else |
| 685 | cp = xstrdup("2"); |
| 686 | #endif |
| 687 | } |
| 688 | if (cp == NULL) |
| 689 | fatal("Unsupported query \"%s\"", optarg); |
| 690 | printf("%s\n", cp); |
| 691 | free(cp); |
| 692 | exit(0); |
| 693 | break; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 694 | case 'a': |
| 695 | options.forward_agent = 0; |
| 696 | break; |
| 697 | case 'A': |
| 698 | options.forward_agent = 1; |
| 699 | break; |
| 700 | case 'k': |
| 701 | options.gss_deleg_creds = 0; |
| 702 | break; |
| 703 | case 'K': |
| 704 | options.gss_authentication = 1; |
| 705 | options.gss_deleg_creds = 1; |
| 706 | break; |
| 707 | case 'i': |
| 708 | if (stat(optarg, &st) < 0) { |
| 709 | fprintf(stderr, "Warning: Identity file %s " |
| 710 | "not accessible: %s.\n", optarg, |
| 711 | strerror(errno)); |
| 712 | break; |
| 713 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 714 | add_identity_file(&options, NULL, optarg, 1); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 715 | break; |
| 716 | case 'I': |
| 717 | #ifdef ENABLE_PKCS11 |
| 718 | options.pkcs11_provider = xstrdup(optarg); |
| 719 | #else |
| 720 | fprintf(stderr, "no support for PKCS#11.\n"); |
| 721 | #endif |
| 722 | break; |
| 723 | case 't': |
| 724 | if (options.request_tty == REQUEST_TTY_YES) |
| 725 | options.request_tty = REQUEST_TTY_FORCE; |
| 726 | else |
| 727 | options.request_tty = REQUEST_TTY_YES; |
| 728 | break; |
| 729 | case 'v': |
| 730 | if (debug_flag == 0) { |
| 731 | debug_flag = 1; |
| 732 | options.log_level = SYSLOG_LEVEL_DEBUG1; |
| 733 | } else { |
| 734 | if (options.log_level < SYSLOG_LEVEL_DEBUG3) |
| 735 | options.log_level++; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 736 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 737 | break; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 738 | case 'V': |
| 739 | fprintf(stderr, "%s, %s\n", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 740 | SSH_RELEASE, |
| 741 | #ifdef WITH_OPENSSL |
| 742 | SSLeay_version(SSLEAY_VERSION) |
| 743 | #else |
| 744 | "without OpenSSL" |
| 745 | #endif |
| 746 | ); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 747 | if (opt == 'V') |
| 748 | exit(0); |
| 749 | break; |
| 750 | case 'w': |
| 751 | if (options.tun_open == -1) |
| 752 | options.tun_open = SSH_TUNMODE_DEFAULT; |
| 753 | options.tun_local = a2tun(optarg, &options.tun_remote); |
| 754 | if (options.tun_local == SSH_TUNID_ERR) { |
| 755 | fprintf(stderr, |
| 756 | "Bad tun device '%s'\n", optarg); |
| 757 | exit(255); |
| 758 | } |
| 759 | break; |
| 760 | case 'W': |
| 761 | if (stdio_forward_host != NULL) |
| 762 | fatal("stdio forward already specified"); |
| 763 | if (muxclient_command != 0) |
| 764 | fatal("Cannot specify stdio forward with -O"); |
| 765 | if (parse_forward(&fwd, optarg, 1, 0)) { |
| 766 | stdio_forward_host = fwd.listen_host; |
| 767 | stdio_forward_port = fwd.listen_port; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 768 | free(fwd.connect_host); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 769 | } else { |
| 770 | fprintf(stderr, |
| 771 | "Bad stdio forwarding specification '%s'\n", |
| 772 | optarg); |
| 773 | exit(255); |
| 774 | } |
| 775 | options.request_tty = REQUEST_TTY_NO; |
| 776 | no_shell_flag = 1; |
| 777 | options.clear_forwardings = 1; |
| 778 | options.exit_on_forward_failure = 1; |
| 779 | break; |
| 780 | case 'q': |
| 781 | options.log_level = SYSLOG_LEVEL_QUIET; |
| 782 | break; |
| 783 | case 'e': |
| 784 | if (optarg[0] == '^' && optarg[2] == 0 && |
| 785 | (u_char) optarg[1] >= 64 && |
| 786 | (u_char) optarg[1] < 128) |
| 787 | options.escape_char = (u_char) optarg[1] & 31; |
| 788 | else if (strlen(optarg) == 1) |
| 789 | options.escape_char = (u_char) optarg[0]; |
| 790 | else if (strcmp(optarg, "none") == 0) |
| 791 | options.escape_char = SSH_ESCAPECHAR_NONE; |
| 792 | else { |
| 793 | fprintf(stderr, "Bad escape character '%s'.\n", |
| 794 | optarg); |
| 795 | exit(255); |
| 796 | } |
| 797 | break; |
| 798 | case 'c': |
| 799 | if (ciphers_valid(optarg)) { |
| 800 | /* SSH2 only */ |
| 801 | options.ciphers = xstrdup(optarg); |
| 802 | options.cipher = SSH_CIPHER_INVALID; |
| 803 | } else { |
| 804 | /* SSH1 only */ |
| 805 | options.cipher = cipher_number(optarg); |
| 806 | if (options.cipher == -1) { |
| 807 | fprintf(stderr, |
| 808 | "Unknown cipher type '%s'\n", |
| 809 | optarg); |
| 810 | exit(255); |
| 811 | } |
| 812 | if (options.cipher == SSH_CIPHER_3DES) |
| 813 | options.ciphers = "3des-cbc"; |
| 814 | else if (options.cipher == SSH_CIPHER_BLOWFISH) |
| 815 | options.ciphers = "blowfish-cbc"; |
| 816 | else |
| 817 | options.ciphers = (char *)-1; |
| 818 | } |
| 819 | break; |
| 820 | case 'm': |
| 821 | if (mac_valid(optarg)) |
| 822 | options.macs = xstrdup(optarg); |
| 823 | else { |
| 824 | fprintf(stderr, "Unknown mac type '%s'\n", |
| 825 | optarg); |
| 826 | exit(255); |
| 827 | } |
| 828 | break; |
| 829 | case 'M': |
| 830 | if (options.control_master == SSHCTL_MASTER_YES) |
| 831 | options.control_master = SSHCTL_MASTER_ASK; |
| 832 | else |
| 833 | options.control_master = SSHCTL_MASTER_YES; |
| 834 | break; |
| 835 | case 'p': |
| 836 | options.port = a2port(optarg); |
| 837 | if (options.port <= 0) { |
| 838 | fprintf(stderr, "Bad port '%s'\n", optarg); |
| 839 | exit(255); |
| 840 | } |
| 841 | break; |
| 842 | case 'l': |
| 843 | options.user = optarg; |
| 844 | break; |
| 845 | |
| 846 | case 'L': |
| 847 | if (parse_forward(&fwd, optarg, 0, 0)) |
| 848 | add_local_forward(&options, &fwd); |
| 849 | else { |
| 850 | fprintf(stderr, |
| 851 | "Bad local forwarding specification '%s'\n", |
| 852 | optarg); |
| 853 | exit(255); |
| 854 | } |
| 855 | break; |
| 856 | |
| 857 | case 'R': |
| 858 | if (parse_forward(&fwd, optarg, 0, 1)) { |
| 859 | add_remote_forward(&options, &fwd); |
| 860 | } else { |
| 861 | fprintf(stderr, |
| 862 | "Bad remote forwarding specification " |
| 863 | "'%s'\n", optarg); |
| 864 | exit(255); |
| 865 | } |
| 866 | break; |
| 867 | |
| 868 | case 'D': |
| 869 | if (parse_forward(&fwd, optarg, 1, 0)) { |
| 870 | add_local_forward(&options, &fwd); |
| 871 | } else { |
| 872 | fprintf(stderr, |
| 873 | "Bad dynamic forwarding specification " |
| 874 | "'%s'\n", optarg); |
| 875 | exit(255); |
| 876 | } |
| 877 | break; |
| 878 | |
| 879 | case 'C': |
| 880 | options.compression = 1; |
| 881 | break; |
| 882 | case 'N': |
| 883 | no_shell_flag = 1; |
| 884 | options.request_tty = REQUEST_TTY_NO; |
| 885 | break; |
| 886 | case 'T': |
| 887 | options.request_tty = REQUEST_TTY_NO; |
| 888 | break; |
| 889 | case 'o': |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 890 | line = xstrdup(optarg); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 891 | if (process_config_line(&options, pw, |
| 892 | host ? host : "", host ? host : "", line, |
| 893 | "command-line", 0, NULL, SSHCONF_USERCONF) != 0) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 894 | exit(255); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 895 | free(line); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 896 | break; |
| 897 | case 's': |
| 898 | subsystem_flag = 1; |
| 899 | break; |
| 900 | case 'S': |
| 901 | if (options.control_path != NULL) |
| 902 | free(options.control_path); |
| 903 | options.control_path = xstrdup(optarg); |
| 904 | break; |
| 905 | case 'b': |
| 906 | options.bind_address = optarg; |
| 907 | break; |
| 908 | case 'F': |
| 909 | config = optarg; |
| 910 | break; |
| 911 | default: |
| 912 | usage(); |
| 913 | } |
| 914 | } |
| 915 | |
| 916 | ac -= optind; |
| 917 | av += optind; |
| 918 | |
| 919 | if (ac > 0 && !host) { |
| 920 | if (strrchr(*av, '@')) { |
| 921 | p = xstrdup(*av); |
| 922 | cp = strrchr(p, '@'); |
| 923 | if (cp == NULL || cp == p) |
| 924 | usage(); |
| 925 | options.user = p; |
| 926 | *cp = '\0'; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 927 | host = xstrdup(++cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 928 | } else |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 929 | host = xstrdup(*av); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 930 | if (ac > 1) { |
| 931 | optind = optreset = 1; |
| 932 | goto again; |
| 933 | } |
| 934 | ac--, av++; |
| 935 | } |
| 936 | |
| 937 | /* Check that we got a host name. */ |
| 938 | if (!host) |
| 939 | usage(); |
| 940 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 941 | host_arg = xstrdup(host); |
| 942 | |
| 943 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 944 | OpenSSL_add_all_algorithms(); |
| 945 | ERR_load_crypto_strings(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 946 | #endif |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 947 | |
| 948 | /* Initialize the command to execute on remote host. */ |
| 949 | buffer_init(&command); |
| 950 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 951 | /* |
| 952 | * Save the command to execute on the remote host in a buffer. There |
| 953 | * is no limit on the length of the command, except by the maximum |
| 954 | * packet size. Also sets the tty flag if there is no command. |
| 955 | */ |
| 956 | if (!ac) { |
| 957 | /* No command specified - execute shell on a tty. */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 958 | if (subsystem_flag) { |
| 959 | fprintf(stderr, |
| 960 | "You must specify a subsystem to invoke.\n"); |
| 961 | usage(); |
| 962 | } |
| 963 | } else { |
| 964 | /* A command has been specified. Store it into the buffer. */ |
| 965 | for (i = 0; i < ac; i++) { |
| 966 | if (i) |
| 967 | buffer_append(&command, " ", 1); |
| 968 | buffer_append(&command, av[i], strlen(av[i])); |
| 969 | } |
| 970 | } |
| 971 | |
| 972 | /* Cannot fork to background if no command. */ |
| 973 | if (fork_after_authentication_flag && buffer_len(&command) == 0 && |
| 974 | !no_shell_flag) |
| 975 | fatal("Cannot fork into background without a command " |
| 976 | "to execute."); |
| 977 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 978 | /* |
| 979 | * Initialize "log" output. Since we are the client all output |
| 980 | * goes to stderr unless otherwise specified by -y or -E. |
| 981 | */ |
| 982 | if (use_syslog && logfile != NULL) |
| 983 | fatal("Can't specify both -y and -E"); |
| 984 | if (logfile != NULL) { |
| 985 | log_redirect_stderr_to(logfile); |
| 986 | free(logfile); |
| 987 | } |
| 988 | log_init(argv0, |
| 989 | options.log_level == -1 ? SYSLOG_LEVEL_INFO : options.log_level, |
| 990 | SYSLOG_FACILITY_USER, !use_syslog); |
| 991 | |
| 992 | if (debug_flag) |
| 993 | logit("%s, %s", SSH_RELEASE, |
| 994 | #ifdef WITH_OPENSSL |
| 995 | SSLeay_version(SSLEAY_VERSION) |
| 996 | #else |
| 997 | "without OpenSSL" |
| 998 | #endif |
| 999 | ); |
| 1000 | |
| 1001 | /* Parse the configuration files */ |
| 1002 | process_config_files(host_arg, pw, 0); |
| 1003 | |
| 1004 | /* Hostname canonicalisation needs a few options filled. */ |
| 1005 | fill_default_options_for_canonicalization(&options); |
| 1006 | |
| 1007 | /* If the user has replaced the hostname then take it into use now */ |
| 1008 | if (options.hostname != NULL) { |
| 1009 | /* NB. Please keep in sync with readconf.c:match_cfg_line() */ |
| 1010 | cp = percent_expand(options.hostname, |
| 1011 | "h", host, (char *)NULL); |
| 1012 | free(host); |
| 1013 | host = cp; |
| 1014 | free(options.hostname); |
| 1015 | options.hostname = xstrdup(host); |
| 1016 | } |
| 1017 | |
| 1018 | /* If canonicalization requested then try to apply it */ |
| 1019 | lowercase(host); |
| 1020 | if (options.canonicalize_hostname != SSH_CANONICALISE_NO) |
| 1021 | addrs = resolve_canonicalize(&host, options.port); |
| 1022 | |
| 1023 | /* |
| 1024 | * If CanonicalizePermittedCNAMEs have been specified but |
| 1025 | * other canonicalization did not happen (by not being requested |
| 1026 | * or by failing with fallback) then the hostname may still be changed |
| 1027 | * as a result of CNAME following. |
| 1028 | * |
| 1029 | * Try to resolve the bare hostname name using the system resolver's |
| 1030 | * usual search rules and then apply the CNAME follow rules. |
| 1031 | * |
| 1032 | * Skip the lookup if a ProxyCommand is being used unless the user |
| 1033 | * has specifically requested canonicalisation for this case via |
| 1034 | * CanonicalizeHostname=always |
| 1035 | */ |
| 1036 | if (addrs == NULL && options.num_permitted_cnames != 0 && |
| 1037 | (option_clear_or_none(options.proxy_command) || |
| 1038 | options.canonicalize_hostname == SSH_CANONICALISE_ALWAYS)) { |
| 1039 | if ((addrs = resolve_host(host, options.port, |
| 1040 | option_clear_or_none(options.proxy_command), |
| 1041 | cname, sizeof(cname))) == NULL) { |
| 1042 | /* Don't fatal proxied host names not in the DNS */ |
| 1043 | if (option_clear_or_none(options.proxy_command)) |
| 1044 | cleanup_exit(255); /* logged in resolve_host */ |
| 1045 | } else |
| 1046 | check_follow_cname(&host, cname); |
| 1047 | } |
| 1048 | |
| 1049 | /* |
| 1050 | * If canonicalisation is enabled then re-parse the configuration |
| 1051 | * files as new stanzas may match. |
| 1052 | */ |
| 1053 | if (options.canonicalize_hostname != 0) { |
| 1054 | debug("Re-reading configuration after hostname " |
| 1055 | "canonicalisation"); |
| 1056 | free(options.hostname); |
| 1057 | options.hostname = xstrdup(host); |
| 1058 | process_config_files(host_arg, pw, 1); |
| 1059 | /* |
| 1060 | * Address resolution happens early with canonicalisation |
| 1061 | * enabled and the port number may have changed since, so |
| 1062 | * reset it in address list |
| 1063 | */ |
| 1064 | if (addrs != NULL && options.port > 0) |
| 1065 | set_addrinfo_port(addrs, options.port); |
| 1066 | } |
| 1067 | |
| 1068 | /* Fill configuration defaults. */ |
| 1069 | fill_default_options(&options); |
| 1070 | |
| 1071 | if (options.port == 0) |
| 1072 | options.port = default_ssh_port(); |
| 1073 | channel_set_af(options.address_family); |
| 1074 | |
| 1075 | /* Tidy and check options */ |
| 1076 | if (options.host_key_alias != NULL) |
| 1077 | lowercase(options.host_key_alias); |
| 1078 | if (options.proxy_command != NULL && |
| 1079 | strcmp(options.proxy_command, "-") == 0 && |
| 1080 | options.proxy_use_fdpass) |
| 1081 | fatal("ProxyCommand=- and ProxyUseFDPass are incompatible"); |
| 1082 | if (options.control_persist && |
| 1083 | options.update_hostkeys == SSH_UPDATE_HOSTKEYS_ASK) { |
| 1084 | debug("UpdateHostKeys=ask is incompatible with ControlPersist; " |
| 1085 | "disabling"); |
| 1086 | options.update_hostkeys = 0; |
| 1087 | } |
| 1088 | #ifndef HAVE_CYGWIN |
| 1089 | if (original_effective_uid != 0) |
| 1090 | options.use_privileged_port = 0; |
| 1091 | #endif |
| 1092 | |
| 1093 | /* reinit */ |
| 1094 | log_init(argv0, options.log_level, SYSLOG_FACILITY_USER, !use_syslog); |
| 1095 | |
| 1096 | if (options.request_tty == REQUEST_TTY_YES || |
| 1097 | options.request_tty == REQUEST_TTY_FORCE) |
| 1098 | tty_flag = 1; |
| 1099 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1100 | /* Allocate a tty by default if no command specified. */ |
| 1101 | if (buffer_len(&command) == 0) |
| 1102 | tty_flag = options.request_tty != REQUEST_TTY_NO; |
| 1103 | |
| 1104 | /* Force no tty */ |
| 1105 | if (options.request_tty == REQUEST_TTY_NO || muxclient_command != 0) |
| 1106 | tty_flag = 0; |
| 1107 | /* Do not allocate a tty if stdin is not a tty. */ |
| 1108 | if ((!isatty(fileno(stdin)) || stdin_null_flag) && |
| 1109 | options.request_tty != REQUEST_TTY_FORCE) { |
| 1110 | if (tty_flag) |
| 1111 | logit("Pseudo-terminal will not be allocated because " |
| 1112 | "stdin is not a terminal."); |
| 1113 | tty_flag = 0; |
| 1114 | } |
| 1115 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1116 | seed_rng(); |
| 1117 | |
| 1118 | if (options.user == NULL) |
| 1119 | options.user = xstrdup(pw->pw_name); |
| 1120 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1121 | if (gethostname(thishost, sizeof(thishost)) == -1) |
| 1122 | fatal("gethostname: %s", strerror(errno)); |
| 1123 | strlcpy(shorthost, thishost, sizeof(shorthost)); |
| 1124 | shorthost[strcspn(thishost, ".")] = '\0'; |
| 1125 | snprintf(portstr, sizeof(portstr), "%d", options.port); |
| 1126 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1127 | if ((md = ssh_digest_start(SSH_DIGEST_SHA1)) == NULL || |
| 1128 | ssh_digest_update(md, thishost, strlen(thishost)) < 0 || |
| 1129 | ssh_digest_update(md, host, strlen(host)) < 0 || |
| 1130 | ssh_digest_update(md, portstr, strlen(portstr)) < 0 || |
| 1131 | ssh_digest_update(md, options.user, strlen(options.user)) < 0 || |
| 1132 | ssh_digest_final(md, conn_hash, sizeof(conn_hash)) < 0) |
| 1133 | fatal("%s: mux digest failed", __func__); |
| 1134 | ssh_digest_free(md); |
| 1135 | conn_hash_hex = tohex(conn_hash, ssh_digest_bytes(SSH_DIGEST_SHA1)); |
| 1136 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1137 | if (options.local_command != NULL) { |
| 1138 | debug3("expanding LocalCommand: %s", options.local_command); |
| 1139 | cp = options.local_command; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1140 | options.local_command = percent_expand(cp, |
| 1141 | "C", conn_hash_hex, |
| 1142 | "L", shorthost, |
| 1143 | "d", pw->pw_dir, |
| 1144 | "h", host, |
| 1145 | "l", thishost, |
| 1146 | "n", host_arg, |
| 1147 | "p", portstr, |
| 1148 | "r", options.user, |
| 1149 | "u", pw->pw_name, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1150 | (char *)NULL); |
| 1151 | debug3("expanded LocalCommand: %s", options.local_command); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1152 | free(cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1153 | } |
| 1154 | |
| 1155 | if (options.control_path != NULL) { |
| 1156 | cp = tilde_expand_filename(options.control_path, |
| 1157 | original_real_uid); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1158 | free(options.control_path); |
| 1159 | options.control_path = percent_expand(cp, |
| 1160 | "C", conn_hash_hex, |
| 1161 | "L", shorthost, |
| 1162 | "h", host, |
| 1163 | "l", thishost, |
| 1164 | "n", host_arg, |
| 1165 | "p", portstr, |
| 1166 | "r", options.user, |
| 1167 | "u", pw->pw_name, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1168 | (char *)NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1169 | free(cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1170 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1171 | free(conn_hash_hex); |
| 1172 | |
| 1173 | if (config_test) { |
| 1174 | dump_client_config(&options, host); |
| 1175 | exit(0); |
| 1176 | } |
| 1177 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1178 | if (muxclient_command != 0 && options.control_path == NULL) |
| 1179 | fatal("No ControlPath specified for \"-O\" command"); |
| 1180 | if (options.control_path != NULL) |
| 1181 | muxclient(options.control_path); |
| 1182 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1183 | /* |
| 1184 | * If hostname canonicalisation was not enabled, then we may not |
| 1185 | * have yet resolved the hostname. Do so now. |
| 1186 | */ |
| 1187 | if (addrs == NULL && options.proxy_command == NULL) { |
| 1188 | if ((addrs = resolve_host(host, options.port, 1, |
| 1189 | cname, sizeof(cname))) == NULL) |
| 1190 | cleanup_exit(255); /* resolve_host logs the error */ |
| 1191 | } |
| 1192 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1193 | timeout_ms = options.connection_timeout * 1000; |
| 1194 | |
| 1195 | /* Open a connection to the remote host. */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1196 | if (ssh_connect(host, addrs, &hostaddr, options.port, |
| 1197 | options.address_family, options.connection_attempts, |
| 1198 | &timeout_ms, options.tcp_keep_alive, |
| 1199 | options.use_privileged_port) != 0) |
| 1200 | exit(255); |
| 1201 | |
| 1202 | if (addrs != NULL) |
| 1203 | freeaddrinfo(addrs); |
| 1204 | |
| 1205 | packet_set_timeout(options.server_alive_interval, |
| 1206 | options.server_alive_count_max); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1207 | |
| 1208 | if (timeout_ms > 0) |
| 1209 | debug3("timeout: %d ms remain after connect", timeout_ms); |
| 1210 | |
| 1211 | /* |
| 1212 | * If we successfully made the connection, load the host private key |
| 1213 | * in case we will need it later for combined rsa-rhosts |
| 1214 | * authentication. This must be done before releasing extra |
| 1215 | * privileges, because the file is only readable by root. |
| 1216 | * If we cannot access the private keys, load the public keys |
| 1217 | * instead and try to execute the ssh-keysign helper instead. |
| 1218 | */ |
| 1219 | sensitive_data.nkeys = 0; |
| 1220 | sensitive_data.keys = NULL; |
| 1221 | sensitive_data.external_keysign = 0; |
| 1222 | if (options.rhosts_rsa_authentication || |
| 1223 | options.hostbased_authentication) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1224 | sensitive_data.nkeys = 9; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1225 | sensitive_data.keys = xcalloc(sensitive_data.nkeys, |
| 1226 | sizeof(Key)); |
| 1227 | for (i = 0; i < sensitive_data.nkeys; i++) |
| 1228 | sensitive_data.keys[i] = NULL; |
| 1229 | |
| 1230 | PRIV_START; |
| 1231 | sensitive_data.keys[0] = key_load_private_type(KEY_RSA1, |
| 1232 | _PATH_HOST_KEY_FILE, "", NULL, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1233 | #ifdef OPENSSL_HAS_ECC |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1234 | sensitive_data.keys[1] = key_load_private_cert(KEY_ECDSA, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1235 | _PATH_HOST_ECDSA_KEY_FILE, "", NULL); |
| 1236 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1237 | sensitive_data.keys[2] = key_load_private_cert(KEY_ED25519, |
| 1238 | _PATH_HOST_ED25519_KEY_FILE, "", NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1239 | sensitive_data.keys[3] = key_load_private_cert(KEY_RSA, |
| 1240 | _PATH_HOST_RSA_KEY_FILE, "", NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1241 | sensitive_data.keys[4] = key_load_private_cert(KEY_DSA, |
| 1242 | _PATH_HOST_DSA_KEY_FILE, "", NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1243 | #ifdef OPENSSL_HAS_ECC |
| 1244 | sensitive_data.keys[5] = key_load_private_type(KEY_ECDSA, |
| 1245 | _PATH_HOST_ECDSA_KEY_FILE, "", NULL, NULL); |
| 1246 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1247 | sensitive_data.keys[6] = key_load_private_type(KEY_ED25519, |
| 1248 | _PATH_HOST_ED25519_KEY_FILE, "", NULL, NULL); |
| 1249 | sensitive_data.keys[7] = key_load_private_type(KEY_RSA, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1250 | _PATH_HOST_RSA_KEY_FILE, "", NULL, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1251 | sensitive_data.keys[8] = key_load_private_type(KEY_DSA, |
| 1252 | _PATH_HOST_DSA_KEY_FILE, "", NULL, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1253 | PRIV_END; |
| 1254 | |
| 1255 | if (options.hostbased_authentication == 1 && |
| 1256 | sensitive_data.keys[0] == NULL && |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1257 | sensitive_data.keys[5] == NULL && |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1258 | sensitive_data.keys[6] == NULL && |
| 1259 | sensitive_data.keys[7] == NULL && |
| 1260 | sensitive_data.keys[8] == NULL) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1261 | #ifdef OPENSSL_HAS_ECC |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1262 | sensitive_data.keys[1] = key_load_cert( |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1263 | _PATH_HOST_ECDSA_KEY_FILE); |
| 1264 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1265 | sensitive_data.keys[2] = key_load_cert( |
| 1266 | _PATH_HOST_ED25519_KEY_FILE); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1267 | sensitive_data.keys[3] = key_load_cert( |
| 1268 | _PATH_HOST_RSA_KEY_FILE); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1269 | sensitive_data.keys[4] = key_load_cert( |
| 1270 | _PATH_HOST_DSA_KEY_FILE); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1271 | #ifdef OPENSSL_HAS_ECC |
| 1272 | sensitive_data.keys[5] = key_load_public( |
| 1273 | _PATH_HOST_ECDSA_KEY_FILE, NULL); |
| 1274 | #endif |
| 1275 | sensitive_data.keys[6] = key_load_public( |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1276 | _PATH_HOST_ED25519_KEY_FILE, NULL); |
| 1277 | sensitive_data.keys[7] = key_load_public( |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1278 | _PATH_HOST_RSA_KEY_FILE, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1279 | sensitive_data.keys[8] = key_load_public( |
| 1280 | _PATH_HOST_DSA_KEY_FILE, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1281 | sensitive_data.external_keysign = 1; |
| 1282 | } |
| 1283 | } |
| 1284 | /* |
| 1285 | * Get rid of any extra privileges that we may have. We will no |
| 1286 | * longer need them. Also, extra privileges could make it very hard |
| 1287 | * to read identity files and other non-world-readable files from the |
| 1288 | * user's home directory if it happens to be on a NFS volume where |
| 1289 | * root is mapped to nobody. |
| 1290 | */ |
| 1291 | if (original_effective_uid == 0) { |
| 1292 | PRIV_START; |
| 1293 | permanently_set_uid(pw); |
| 1294 | } |
| 1295 | |
| 1296 | /* |
| 1297 | * Now that we are back to our own permissions, create ~/.ssh |
| 1298 | * directory if it doesn't already exist. |
| 1299 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1300 | if (config == NULL) { |
| 1301 | r = snprintf(buf, sizeof buf, "%s%s%s", pw->pw_dir, |
| 1302 | strcmp(pw->pw_dir, "/") ? "/" : "", _PATH_SSH_USER_DIR); |
| 1303 | if (r > 0 && (size_t)r < sizeof(buf) && stat(buf, &st) < 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1304 | #ifdef WITH_SELINUX |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1305 | ssh_selinux_setfscreatecon(buf); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1306 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1307 | if (mkdir(buf, 0700) < 0) |
| 1308 | error("Could not create directory '%.200s'.", |
| 1309 | buf); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1310 | #ifdef WITH_SELINUX |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1311 | ssh_selinux_setfscreatecon(NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1312 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1313 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1314 | } |
| 1315 | /* load options.identity_files */ |
| 1316 | load_public_identity_files(); |
| 1317 | |
| 1318 | /* Expand ~ in known host file names. */ |
| 1319 | tilde_expand_paths(options.system_hostfiles, |
| 1320 | options.num_system_hostfiles); |
| 1321 | tilde_expand_paths(options.user_hostfiles, options.num_user_hostfiles); |
| 1322 | |
| 1323 | signal(SIGPIPE, SIG_IGN); /* ignore SIGPIPE early */ |
| 1324 | signal(SIGCHLD, main_sigchld_handler); |
| 1325 | |
| 1326 | /* Log into the remote system. Never returns if the login fails. */ |
| 1327 | ssh_login(&sensitive_data, host, (struct sockaddr *)&hostaddr, |
| 1328 | options.port, pw, timeout_ms); |
| 1329 | |
| 1330 | if (packet_connection_is_on_socket()) { |
| 1331 | verbose("Authenticated to %s ([%s]:%d).", host, |
| 1332 | get_remote_ipaddr(), get_remote_port()); |
| 1333 | } else { |
| 1334 | verbose("Authenticated to %s (via proxy).", host); |
| 1335 | } |
| 1336 | |
| 1337 | /* We no longer need the private host keys. Clear them now. */ |
| 1338 | if (sensitive_data.nkeys != 0) { |
| 1339 | for (i = 0; i < sensitive_data.nkeys; i++) { |
| 1340 | if (sensitive_data.keys[i] != NULL) { |
| 1341 | /* Destroys contents safely */ |
| 1342 | debug3("clear hostkey %d", i); |
| 1343 | key_free(sensitive_data.keys[i]); |
| 1344 | sensitive_data.keys[i] = NULL; |
| 1345 | } |
| 1346 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1347 | free(sensitive_data.keys); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1348 | } |
| 1349 | for (i = 0; i < options.num_identity_files; i++) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1350 | free(options.identity_files[i]); |
| 1351 | options.identity_files[i] = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1352 | if (options.identity_keys[i]) { |
| 1353 | key_free(options.identity_keys[i]); |
| 1354 | options.identity_keys[i] = NULL; |
| 1355 | } |
| 1356 | } |
| 1357 | |
| 1358 | exit_status = compat20 ? ssh_session2() : ssh_session(); |
| 1359 | packet_close(); |
| 1360 | |
| 1361 | if (options.control_path != NULL && muxserver_sock != -1) |
| 1362 | unlink(options.control_path); |
| 1363 | |
| 1364 | /* Kill ProxyCommand if it is running. */ |
| 1365 | ssh_kill_proxy_command(); |
| 1366 | |
| 1367 | return exit_status; |
| 1368 | } |
| 1369 | |
| 1370 | static void |
| 1371 | control_persist_detach(void) |
| 1372 | { |
| 1373 | pid_t pid; |
| 1374 | int devnull; |
| 1375 | |
| 1376 | debug("%s: backgrounding master process", __func__); |
| 1377 | |
| 1378 | /* |
| 1379 | * master (current process) into the background, and make the |
| 1380 | * foreground process a client of the backgrounded master. |
| 1381 | */ |
| 1382 | switch ((pid = fork())) { |
| 1383 | case -1: |
| 1384 | fatal("%s: fork: %s", __func__, strerror(errno)); |
| 1385 | case 0: |
| 1386 | /* Child: master process continues mainloop */ |
| 1387 | break; |
| 1388 | default: |
| 1389 | /* Parent: set up mux slave to connect to backgrounded master */ |
| 1390 | debug2("%s: background process is %ld", __func__, (long)pid); |
| 1391 | stdin_null_flag = ostdin_null_flag; |
| 1392 | options.request_tty = orequest_tty; |
| 1393 | tty_flag = otty_flag; |
| 1394 | close(muxserver_sock); |
| 1395 | muxserver_sock = -1; |
| 1396 | options.control_master = SSHCTL_MASTER_NO; |
| 1397 | muxclient(options.control_path); |
| 1398 | /* muxclient() doesn't return on success. */ |
| 1399 | fatal("Failed to connect to new control master"); |
| 1400 | } |
| 1401 | if ((devnull = open(_PATH_DEVNULL, O_RDWR)) == -1) { |
| 1402 | error("%s: open(\"/dev/null\"): %s", __func__, |
| 1403 | strerror(errno)); |
| 1404 | } else { |
| 1405 | if (dup2(devnull, STDIN_FILENO) == -1 || |
| 1406 | dup2(devnull, STDOUT_FILENO) == -1) |
| 1407 | error("%s: dup2: %s", __func__, strerror(errno)); |
| 1408 | if (devnull > STDERR_FILENO) |
| 1409 | close(devnull); |
| 1410 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1411 | daemon(1, 1); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1412 | setproctitle("%s [mux]", options.control_path); |
| 1413 | } |
| 1414 | |
| 1415 | /* Do fork() after authentication. Used by "ssh -f" */ |
| 1416 | static void |
| 1417 | fork_postauth(void) |
| 1418 | { |
| 1419 | if (need_controlpersist_detach) |
| 1420 | control_persist_detach(); |
| 1421 | debug("forking to background"); |
| 1422 | fork_after_authentication_flag = 0; |
| 1423 | if (daemon(1, 1) < 0) |
| 1424 | fatal("daemon() failed: %.200s", strerror(errno)); |
| 1425 | } |
| 1426 | |
| 1427 | /* Callback for remote forward global requests */ |
| 1428 | static void |
| 1429 | ssh_confirm_remote_forward(int type, u_int32_t seq, void *ctxt) |
| 1430 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1431 | struct Forward *rfwd = (struct Forward *)ctxt; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1432 | |
| 1433 | /* XXX verbose() on failure? */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1434 | debug("remote forward %s for: listen %s%s%d, connect %s:%d", |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1435 | type == SSH2_MSG_REQUEST_SUCCESS ? "success" : "failure", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1436 | rfwd->listen_path ? rfwd->listen_path : |
| 1437 | rfwd->listen_host ? rfwd->listen_host : "", |
| 1438 | (rfwd->listen_path || rfwd->listen_host) ? ":" : "", |
| 1439 | rfwd->listen_port, rfwd->connect_path ? rfwd->connect_path : |
| 1440 | rfwd->connect_host, rfwd->connect_port); |
| 1441 | if (rfwd->listen_path == NULL && rfwd->listen_port == 0) { |
| 1442 | if (type == SSH2_MSG_REQUEST_SUCCESS) { |
| 1443 | rfwd->allocated_port = packet_get_int(); |
| 1444 | logit("Allocated port %u for remote forward to %s:%d", |
| 1445 | rfwd->allocated_port, |
| 1446 | rfwd->connect_host, rfwd->connect_port); |
| 1447 | channel_update_permitted_opens(rfwd->handle, |
| 1448 | rfwd->allocated_port); |
| 1449 | } else { |
| 1450 | channel_update_permitted_opens(rfwd->handle, -1); |
| 1451 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1452 | } |
| 1453 | |
| 1454 | if (type == SSH2_MSG_REQUEST_FAILURE) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1455 | if (options.exit_on_forward_failure) { |
| 1456 | if (rfwd->listen_path != NULL) |
| 1457 | fatal("Error: remote port forwarding failed " |
| 1458 | "for listen path %s", rfwd->listen_path); |
| 1459 | else |
| 1460 | fatal("Error: remote port forwarding failed " |
| 1461 | "for listen port %d", rfwd->listen_port); |
| 1462 | } else { |
| 1463 | if (rfwd->listen_path != NULL) |
| 1464 | logit("Warning: remote port forwarding failed " |
| 1465 | "for listen path %s", rfwd->listen_path); |
| 1466 | else |
| 1467 | logit("Warning: remote port forwarding failed " |
| 1468 | "for listen port %d", rfwd->listen_port); |
| 1469 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1470 | } |
| 1471 | if (++remote_forward_confirms_received == options.num_remote_forwards) { |
| 1472 | debug("All remote forwarding requests processed"); |
| 1473 | if (fork_after_authentication_flag) |
| 1474 | fork_postauth(); |
| 1475 | } |
| 1476 | } |
| 1477 | |
| 1478 | static void |
| 1479 | client_cleanup_stdio_fwd(int id, void *arg) |
| 1480 | { |
| 1481 | debug("stdio forwarding: done"); |
| 1482 | cleanup_exit(0); |
| 1483 | } |
| 1484 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1485 | static void |
| 1486 | ssh_stdio_confirm(int id, int success, void *arg) |
| 1487 | { |
| 1488 | if (!success) |
| 1489 | fatal("stdio forwarding failed"); |
| 1490 | } |
| 1491 | |
| 1492 | static void |
| 1493 | ssh_init_stdio_forwarding(void) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1494 | { |
| 1495 | Channel *c; |
| 1496 | int in, out; |
| 1497 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1498 | if (stdio_forward_host == NULL) |
| 1499 | return; |
| 1500 | if (!compat20) |
| 1501 | fatal("stdio forwarding require Protocol 2"); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1502 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1503 | debug3("%s: %s:%d", __func__, stdio_forward_host, stdio_forward_port); |
| 1504 | |
| 1505 | if ((in = dup(STDIN_FILENO)) < 0 || |
| 1506 | (out = dup(STDOUT_FILENO)) < 0) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1507 | fatal("channel_connect_stdio_fwd: dup() in/out failed"); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1508 | if ((c = channel_connect_stdio_fwd(stdio_forward_host, |
| 1509 | stdio_forward_port, in, out)) == NULL) |
| 1510 | fatal("%s: channel_connect_stdio_fwd failed", __func__); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1511 | channel_register_cleanup(c->self, client_cleanup_stdio_fwd, 0); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1512 | channel_register_open_confirm(c->self, ssh_stdio_confirm, NULL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1513 | } |
| 1514 | |
| 1515 | static void |
| 1516 | ssh_init_forwarding(void) |
| 1517 | { |
| 1518 | int success = 0; |
| 1519 | int i; |
| 1520 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1521 | /* Initiate local TCP/IP port forwardings. */ |
| 1522 | for (i = 0; i < options.num_local_forwards; i++) { |
| 1523 | debug("Local connections to %.200s:%d forwarded to remote " |
| 1524 | "address %.200s:%d", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1525 | (options.local_forwards[i].listen_path != NULL) ? |
| 1526 | options.local_forwards[i].listen_path : |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1527 | (options.local_forwards[i].listen_host == NULL) ? |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1528 | (options.fwd_opts.gateway_ports ? "*" : "LOCALHOST") : |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1529 | options.local_forwards[i].listen_host, |
| 1530 | options.local_forwards[i].listen_port, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1531 | (options.local_forwards[i].connect_path != NULL) ? |
| 1532 | options.local_forwards[i].connect_path : |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1533 | options.local_forwards[i].connect_host, |
| 1534 | options.local_forwards[i].connect_port); |
| 1535 | success += channel_setup_local_fwd_listener( |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1536 | &options.local_forwards[i], &options.fwd_opts); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1537 | } |
| 1538 | if (i > 0 && success != i && options.exit_on_forward_failure) |
| 1539 | fatal("Could not request local forwarding."); |
| 1540 | if (i > 0 && success == 0) |
| 1541 | error("Could not request local forwarding."); |
| 1542 | |
| 1543 | /* Initiate remote TCP/IP port forwardings. */ |
| 1544 | for (i = 0; i < options.num_remote_forwards; i++) { |
| 1545 | debug("Remote connections from %.200s:%d forwarded to " |
| 1546 | "local address %.200s:%d", |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1547 | (options.remote_forwards[i].listen_path != NULL) ? |
| 1548 | options.remote_forwards[i].listen_path : |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1549 | (options.remote_forwards[i].listen_host == NULL) ? |
| 1550 | "LOCALHOST" : options.remote_forwards[i].listen_host, |
| 1551 | options.remote_forwards[i].listen_port, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1552 | (options.remote_forwards[i].connect_path != NULL) ? |
| 1553 | options.remote_forwards[i].connect_path : |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1554 | options.remote_forwards[i].connect_host, |
| 1555 | options.remote_forwards[i].connect_port); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1556 | options.remote_forwards[i].handle = |
| 1557 | channel_request_remote_forwarding( |
| 1558 | &options.remote_forwards[i]); |
| 1559 | if (options.remote_forwards[i].handle < 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1560 | if (options.exit_on_forward_failure) |
| 1561 | fatal("Could not request remote forwarding."); |
| 1562 | else |
| 1563 | logit("Warning: Could not request remote " |
| 1564 | "forwarding."); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1565 | } else { |
| 1566 | client_register_global_confirm(ssh_confirm_remote_forward, |
| 1567 | &options.remote_forwards[i]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1568 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1569 | } |
| 1570 | |
| 1571 | /* Initiate tunnel forwarding. */ |
| 1572 | if (options.tun_open != SSH_TUNMODE_NO) { |
| 1573 | if (client_request_tun_fwd(options.tun_open, |
| 1574 | options.tun_local, options.tun_remote) == -1) { |
| 1575 | if (options.exit_on_forward_failure) |
| 1576 | fatal("Could not request tunnel forwarding."); |
| 1577 | else |
| 1578 | error("Could not request tunnel forwarding."); |
| 1579 | } |
| 1580 | } |
| 1581 | } |
| 1582 | |
| 1583 | static void |
| 1584 | check_agent_present(void) |
| 1585 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1586 | int r; |
| 1587 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1588 | if (options.forward_agent) { |
| 1589 | /* Clear agent forwarding if we don't have an agent. */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1590 | if ((r = ssh_get_authentication_socket(NULL)) != 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1591 | options.forward_agent = 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1592 | if (r != SSH_ERR_AGENT_NOT_PRESENT) |
| 1593 | debug("ssh_get_authentication_socket: %s", |
| 1594 | ssh_err(r)); |
| 1595 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1596 | } |
| 1597 | } |
| 1598 | |
| 1599 | static int |
| 1600 | ssh_session(void) |
| 1601 | { |
| 1602 | int type; |
| 1603 | int interactive = 0; |
| 1604 | int have_tty = 0; |
| 1605 | struct winsize ws; |
| 1606 | char *cp; |
| 1607 | const char *display; |
| 1608 | |
| 1609 | /* Enable compression if requested. */ |
| 1610 | if (options.compression) { |
| 1611 | debug("Requesting compression at level %d.", |
| 1612 | options.compression_level); |
| 1613 | |
| 1614 | if (options.compression_level < 1 || |
| 1615 | options.compression_level > 9) |
| 1616 | fatal("Compression level must be from 1 (fast) to " |
| 1617 | "9 (slow, best)."); |
| 1618 | |
| 1619 | /* Send the request. */ |
| 1620 | packet_start(SSH_CMSG_REQUEST_COMPRESSION); |
| 1621 | packet_put_int(options.compression_level); |
| 1622 | packet_send(); |
| 1623 | packet_write_wait(); |
| 1624 | type = packet_read(); |
| 1625 | if (type == SSH_SMSG_SUCCESS) |
| 1626 | packet_start_compression(options.compression_level); |
| 1627 | else if (type == SSH_SMSG_FAILURE) |
| 1628 | logit("Warning: Remote host refused compression."); |
| 1629 | else |
| 1630 | packet_disconnect("Protocol error waiting for " |
| 1631 | "compression response."); |
| 1632 | } |
| 1633 | /* Allocate a pseudo tty if appropriate. */ |
| 1634 | if (tty_flag) { |
| 1635 | debug("Requesting pty."); |
| 1636 | |
| 1637 | /* Start the packet. */ |
| 1638 | packet_start(SSH_CMSG_REQUEST_PTY); |
| 1639 | |
| 1640 | /* Store TERM in the packet. There is no limit on the |
| 1641 | length of the string. */ |
| 1642 | cp = getenv("TERM"); |
| 1643 | if (!cp) |
| 1644 | cp = ""; |
| 1645 | packet_put_cstring(cp); |
| 1646 | |
| 1647 | /* Store window size in the packet. */ |
| 1648 | if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0) |
| 1649 | memset(&ws, 0, sizeof(ws)); |
| 1650 | packet_put_int((u_int)ws.ws_row); |
| 1651 | packet_put_int((u_int)ws.ws_col); |
| 1652 | packet_put_int((u_int)ws.ws_xpixel); |
| 1653 | packet_put_int((u_int)ws.ws_ypixel); |
| 1654 | |
| 1655 | /* Store tty modes in the packet. */ |
| 1656 | tty_make_modes(fileno(stdin), NULL); |
| 1657 | |
| 1658 | /* Send the packet, and wait for it to leave. */ |
| 1659 | packet_send(); |
| 1660 | packet_write_wait(); |
| 1661 | |
| 1662 | /* Read response from the server. */ |
| 1663 | type = packet_read(); |
| 1664 | if (type == SSH_SMSG_SUCCESS) { |
| 1665 | interactive = 1; |
| 1666 | have_tty = 1; |
| 1667 | } else if (type == SSH_SMSG_FAILURE) |
| 1668 | logit("Warning: Remote host failed or refused to " |
| 1669 | "allocate a pseudo tty."); |
| 1670 | else |
| 1671 | packet_disconnect("Protocol error waiting for pty " |
| 1672 | "request response."); |
| 1673 | } |
| 1674 | /* Request X11 forwarding if enabled and DISPLAY is set. */ |
| 1675 | display = getenv("DISPLAY"); |
| 1676 | if (options.forward_x11 && display != NULL) { |
| 1677 | char *proto, *data; |
| 1678 | /* Get reasonable local authentication information. */ |
| 1679 | client_x11_get_proto(display, options.xauth_location, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1680 | options.forward_x11_trusted, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1681 | options.forward_x11_timeout, |
| 1682 | &proto, &data); |
| 1683 | /* Request forwarding with authentication spoofing. */ |
| 1684 | debug("Requesting X11 forwarding with authentication " |
| 1685 | "spoofing."); |
| 1686 | x11_request_forwarding_with_spoofing(0, display, proto, |
| 1687 | data, 0); |
| 1688 | /* Read response from the server. */ |
| 1689 | type = packet_read(); |
| 1690 | if (type == SSH_SMSG_SUCCESS) { |
| 1691 | interactive = 1; |
| 1692 | } else if (type == SSH_SMSG_FAILURE) { |
| 1693 | logit("Warning: Remote host denied X11 forwarding."); |
| 1694 | } else { |
| 1695 | packet_disconnect("Protocol error waiting for X11 " |
| 1696 | "forwarding"); |
| 1697 | } |
| 1698 | } |
| 1699 | /* Tell the packet module whether this is an interactive session. */ |
| 1700 | packet_set_interactive(interactive, |
| 1701 | options.ip_qos_interactive, options.ip_qos_bulk); |
| 1702 | |
| 1703 | /* Request authentication agent forwarding if appropriate. */ |
| 1704 | check_agent_present(); |
| 1705 | |
| 1706 | if (options.forward_agent) { |
| 1707 | debug("Requesting authentication agent forwarding."); |
| 1708 | auth_request_forwarding(); |
| 1709 | |
| 1710 | /* Read response from the server. */ |
| 1711 | type = packet_read(); |
| 1712 | packet_check_eom(); |
| 1713 | if (type != SSH_SMSG_SUCCESS) |
| 1714 | logit("Warning: Remote host denied authentication agent forwarding."); |
| 1715 | } |
| 1716 | |
| 1717 | /* Initiate port forwardings. */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1718 | ssh_init_stdio_forwarding(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1719 | ssh_init_forwarding(); |
| 1720 | |
| 1721 | /* Execute a local command */ |
| 1722 | if (options.local_command != NULL && |
| 1723 | options.permit_local_command) |
| 1724 | ssh_local_cmd(options.local_command); |
| 1725 | |
| 1726 | /* |
| 1727 | * If requested and we are not interested in replies to remote |
| 1728 | * forwarding requests, then let ssh continue in the background. |
| 1729 | */ |
| 1730 | if (fork_after_authentication_flag) { |
| 1731 | if (options.exit_on_forward_failure && |
| 1732 | options.num_remote_forwards > 0) { |
| 1733 | debug("deferring postauth fork until remote forward " |
| 1734 | "confirmation received"); |
| 1735 | } else |
| 1736 | fork_postauth(); |
| 1737 | } |
| 1738 | |
| 1739 | /* |
| 1740 | * If a command was specified on the command line, execute the |
| 1741 | * command now. Otherwise request the server to start a shell. |
| 1742 | */ |
| 1743 | if (buffer_len(&command) > 0) { |
| 1744 | int len = buffer_len(&command); |
| 1745 | if (len > 900) |
| 1746 | len = 900; |
| 1747 | debug("Sending command: %.*s", len, |
| 1748 | (u_char *)buffer_ptr(&command)); |
| 1749 | packet_start(SSH_CMSG_EXEC_CMD); |
| 1750 | packet_put_string(buffer_ptr(&command), buffer_len(&command)); |
| 1751 | packet_send(); |
| 1752 | packet_write_wait(); |
| 1753 | } else { |
| 1754 | debug("Requesting shell."); |
| 1755 | packet_start(SSH_CMSG_EXEC_SHELL); |
| 1756 | packet_send(); |
| 1757 | packet_write_wait(); |
| 1758 | } |
| 1759 | |
| 1760 | /* Enter the interactive session. */ |
| 1761 | return client_loop(have_tty, tty_flag ? |
| 1762 | options.escape_char : SSH_ESCAPECHAR_NONE, 0); |
| 1763 | } |
| 1764 | |
| 1765 | /* request pty/x11/agent/tcpfwd/shell for channel */ |
| 1766 | static void |
| 1767 | ssh_session2_setup(int id, int success, void *arg) |
| 1768 | { |
| 1769 | extern char **environ; |
| 1770 | const char *display; |
| 1771 | int interactive = tty_flag; |
| 1772 | |
| 1773 | if (!success) |
| 1774 | return; /* No need for error message, channels code sens one */ |
| 1775 | |
| 1776 | display = getenv("DISPLAY"); |
| 1777 | if (options.forward_x11 && display != NULL) { |
| 1778 | char *proto, *data; |
| 1779 | /* Get reasonable local authentication information. */ |
| 1780 | client_x11_get_proto(display, options.xauth_location, |
| 1781 | options.forward_x11_trusted, |
| 1782 | options.forward_x11_timeout, &proto, &data); |
| 1783 | /* Request forwarding with authentication spoofing. */ |
| 1784 | debug("Requesting X11 forwarding with authentication " |
| 1785 | "spoofing."); |
| 1786 | x11_request_forwarding_with_spoofing(id, display, proto, |
| 1787 | data, 1); |
| 1788 | client_expect_confirm(id, "X11 forwarding", CONFIRM_WARN); |
| 1789 | /* XXX exit_on_forward_failure */ |
| 1790 | interactive = 1; |
| 1791 | } |
| 1792 | |
| 1793 | check_agent_present(); |
| 1794 | if (options.forward_agent) { |
| 1795 | debug("Requesting authentication agent forwarding."); |
| 1796 | channel_request_start(id, "auth-agent-req@openssh.com", 0); |
| 1797 | packet_send(); |
| 1798 | } |
| 1799 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1800 | /* Tell the packet module whether this is an interactive session. */ |
| 1801 | packet_set_interactive(interactive, |
| 1802 | options.ip_qos_interactive, options.ip_qos_bulk); |
| 1803 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1804 | client_session2_setup(id, tty_flag, subsystem_flag, getenv("TERM"), |
| 1805 | NULL, fileno(stdin), &command, environ); |
| 1806 | } |
| 1807 | |
| 1808 | /* open new channel for a session */ |
| 1809 | static int |
| 1810 | ssh_session2_open(void) |
| 1811 | { |
| 1812 | Channel *c; |
| 1813 | int window, packetmax, in, out, err; |
| 1814 | |
| 1815 | if (stdin_null_flag) { |
| 1816 | in = open(_PATH_DEVNULL, O_RDONLY); |
| 1817 | } else { |
| 1818 | in = dup(STDIN_FILENO); |
| 1819 | } |
| 1820 | out = dup(STDOUT_FILENO); |
| 1821 | err = dup(STDERR_FILENO); |
| 1822 | |
| 1823 | if (in < 0 || out < 0 || err < 0) |
| 1824 | fatal("dup() in/out/err failed"); |
| 1825 | |
| 1826 | /* enable nonblocking unless tty */ |
| 1827 | if (!isatty(in)) |
| 1828 | set_nonblock(in); |
| 1829 | if (!isatty(out)) |
| 1830 | set_nonblock(out); |
| 1831 | if (!isatty(err)) |
| 1832 | set_nonblock(err); |
| 1833 | |
| 1834 | window = CHAN_SES_WINDOW_DEFAULT; |
| 1835 | packetmax = CHAN_SES_PACKET_DEFAULT; |
| 1836 | if (tty_flag) { |
| 1837 | window >>= 1; |
| 1838 | packetmax >>= 1; |
| 1839 | } |
| 1840 | c = channel_new( |
| 1841 | "session", SSH_CHANNEL_OPENING, in, out, err, |
| 1842 | window, packetmax, CHAN_EXTENDED_WRITE, |
| 1843 | "client-session", /*nonblock*/0); |
| 1844 | |
| 1845 | debug3("ssh_session2_open: channel_new: %d", c->self); |
| 1846 | |
| 1847 | channel_send_open(c->self); |
| 1848 | if (!no_shell_flag) |
| 1849 | channel_register_open_confirm(c->self, |
| 1850 | ssh_session2_setup, NULL); |
| 1851 | |
| 1852 | return c->self; |
| 1853 | } |
| 1854 | |
| 1855 | static int |
| 1856 | ssh_session2(void) |
| 1857 | { |
| 1858 | int id = -1; |
| 1859 | |
| 1860 | /* XXX should be pre-session */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1861 | if (!options.control_persist) |
| 1862 | ssh_init_stdio_forwarding(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1863 | ssh_init_forwarding(); |
| 1864 | |
| 1865 | /* Start listening for multiplex clients */ |
| 1866 | muxserver_listen(); |
| 1867 | |
| 1868 | /* |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1869 | * If we are in control persist mode and have a working mux listen |
| 1870 | * socket, then prepare to background ourselves and have a foreground |
| 1871 | * client attach as a control slave. |
| 1872 | * NB. we must save copies of the flags that we override for |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1873 | * the backgrounding, since we defer attachment of the slave until |
| 1874 | * after the connection is fully established (in particular, |
| 1875 | * async rfwd replies have been received for ExitOnForwardFailure). |
| 1876 | */ |
| 1877 | if (options.control_persist && muxserver_sock != -1) { |
| 1878 | ostdin_null_flag = stdin_null_flag; |
| 1879 | ono_shell_flag = no_shell_flag; |
| 1880 | orequest_tty = options.request_tty; |
| 1881 | otty_flag = tty_flag; |
| 1882 | stdin_null_flag = 1; |
| 1883 | no_shell_flag = 1; |
| 1884 | tty_flag = 0; |
| 1885 | if (!fork_after_authentication_flag) |
| 1886 | need_controlpersist_detach = 1; |
| 1887 | fork_after_authentication_flag = 1; |
| 1888 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1889 | /* |
| 1890 | * ControlPersist mux listen socket setup failed, attempt the |
| 1891 | * stdio forward setup that we skipped earlier. |
| 1892 | */ |
| 1893 | if (options.control_persist && muxserver_sock == -1) |
| 1894 | ssh_init_stdio_forwarding(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1895 | |
| 1896 | if (!no_shell_flag || (datafellows & SSH_BUG_DUMMYCHAN)) |
| 1897 | id = ssh_session2_open(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1898 | else { |
| 1899 | packet_set_interactive( |
| 1900 | options.control_master == SSHCTL_MASTER_NO, |
| 1901 | options.ip_qos_interactive, options.ip_qos_bulk); |
| 1902 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1903 | |
| 1904 | /* If we don't expect to open a new session, then disallow it */ |
| 1905 | if (options.control_master == SSHCTL_MASTER_NO && |
| 1906 | (datafellows & SSH_NEW_OPENSSH)) { |
| 1907 | debug("Requesting no-more-sessions@openssh.com"); |
| 1908 | packet_start(SSH2_MSG_GLOBAL_REQUEST); |
| 1909 | packet_put_cstring("no-more-sessions@openssh.com"); |
| 1910 | packet_put_char(0); |
| 1911 | packet_send(); |
| 1912 | } |
| 1913 | |
| 1914 | /* Execute a local command */ |
| 1915 | if (options.local_command != NULL && |
| 1916 | options.permit_local_command) |
| 1917 | ssh_local_cmd(options.local_command); |
| 1918 | |
| 1919 | /* |
| 1920 | * If requested and we are not interested in replies to remote |
| 1921 | * forwarding requests, then let ssh continue in the background. |
| 1922 | */ |
| 1923 | if (fork_after_authentication_flag) { |
| 1924 | if (options.exit_on_forward_failure && |
| 1925 | options.num_remote_forwards > 0) { |
| 1926 | debug("deferring postauth fork until remote forward " |
| 1927 | "confirmation received"); |
| 1928 | } else |
| 1929 | fork_postauth(); |
| 1930 | } |
| 1931 | |
| 1932 | if (options.use_roaming) |
| 1933 | request_roaming(); |
| 1934 | |
| 1935 | return client_loop(tty_flag, tty_flag ? |
| 1936 | options.escape_char : SSH_ESCAPECHAR_NONE, id); |
| 1937 | } |
| 1938 | |
| 1939 | static void |
| 1940 | load_public_identity_files(void) |
| 1941 | { |
| 1942 | char *filename, *cp, thishost[NI_MAXHOST]; |
| 1943 | char *pwdir = NULL, *pwname = NULL; |
| 1944 | int i = 0; |
| 1945 | Key *public; |
| 1946 | struct passwd *pw; |
| 1947 | u_int n_ids; |
| 1948 | char *identity_files[SSH_MAX_IDENTITY_FILES]; |
| 1949 | Key *identity_keys[SSH_MAX_IDENTITY_FILES]; |
| 1950 | #ifdef ENABLE_PKCS11 |
| 1951 | Key **keys; |
| 1952 | int nkeys; |
| 1953 | #endif /* PKCS11 */ |
| 1954 | |
| 1955 | n_ids = 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1956 | memset(identity_files, 0, sizeof(identity_files)); |
| 1957 | memset(identity_keys, 0, sizeof(identity_keys)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1958 | |
| 1959 | #ifdef ENABLE_PKCS11 |
| 1960 | if (options.pkcs11_provider != NULL && |
| 1961 | options.num_identity_files < SSH_MAX_IDENTITY_FILES && |
| 1962 | (pkcs11_init(!options.batch_mode) == 0) && |
| 1963 | (nkeys = pkcs11_add_provider(options.pkcs11_provider, NULL, |
| 1964 | &keys)) > 0) { |
| 1965 | for (i = 0; i < nkeys; i++) { |
| 1966 | if (n_ids >= SSH_MAX_IDENTITY_FILES) { |
| 1967 | key_free(keys[i]); |
| 1968 | continue; |
| 1969 | } |
| 1970 | identity_keys[n_ids] = keys[i]; |
| 1971 | identity_files[n_ids] = |
| 1972 | xstrdup(options.pkcs11_provider); /* XXX */ |
| 1973 | n_ids++; |
| 1974 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1975 | free(keys); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1976 | } |
| 1977 | #endif /* ENABLE_PKCS11 */ |
| 1978 | if ((pw = getpwuid(original_real_uid)) == NULL) |
| 1979 | fatal("load_public_identity_files: getpwuid failed"); |
| 1980 | pwname = xstrdup(pw->pw_name); |
| 1981 | pwdir = xstrdup(pw->pw_dir); |
| 1982 | if (gethostname(thishost, sizeof(thishost)) == -1) |
| 1983 | fatal("load_public_identity_files: gethostname: %s", |
| 1984 | strerror(errno)); |
| 1985 | for (i = 0; i < options.num_identity_files; i++) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1986 | if (n_ids >= SSH_MAX_IDENTITY_FILES || |
| 1987 | strcasecmp(options.identity_files[i], "none") == 0) { |
| 1988 | free(options.identity_files[i]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1989 | continue; |
| 1990 | } |
| 1991 | cp = tilde_expand_filename(options.identity_files[i], |
| 1992 | original_real_uid); |
| 1993 | filename = percent_expand(cp, "d", pwdir, |
| 1994 | "u", pwname, "l", thishost, "h", host, |
| 1995 | "r", options.user, (char *)NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 1996 | free(cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1997 | public = key_load_public(filename, NULL); |
| 1998 | debug("identity file %s type %d", filename, |
| 1999 | public ? public->type : -1); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 2000 | free(options.identity_files[i]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2001 | identity_files[n_ids] = filename; |
| 2002 | identity_keys[n_ids] = public; |
| 2003 | |
| 2004 | if (++n_ids >= SSH_MAX_IDENTITY_FILES) |
| 2005 | continue; |
| 2006 | |
| 2007 | /* Try to add the certificate variant too */ |
| 2008 | xasprintf(&cp, "%s-cert", filename); |
| 2009 | public = key_load_public(cp, NULL); |
| 2010 | debug("identity file %s type %d", cp, |
| 2011 | public ? public->type : -1); |
| 2012 | if (public == NULL) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 2013 | free(cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2014 | continue; |
| 2015 | } |
| 2016 | if (!key_is_cert(public)) { |
| 2017 | debug("%s: key %s type %s is not a certificate", |
| 2018 | __func__, cp, key_type(public)); |
| 2019 | key_free(public); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 2020 | free(cp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2021 | continue; |
| 2022 | } |
| 2023 | identity_keys[n_ids] = public; |
| 2024 | /* point to the original path, most likely the private key */ |
| 2025 | identity_files[n_ids] = xstrdup(filename); |
| 2026 | n_ids++; |
| 2027 | } |
| 2028 | options.num_identity_files = n_ids; |
| 2029 | memcpy(options.identity_files, identity_files, sizeof(identity_files)); |
| 2030 | memcpy(options.identity_keys, identity_keys, sizeof(identity_keys)); |
| 2031 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame^] | 2032 | explicit_bzero(pwname, strlen(pwname)); |
| 2033 | free(pwname); |
| 2034 | explicit_bzero(pwdir, strlen(pwdir)); |
| 2035 | free(pwdir); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2036 | } |
| 2037 | |
| 2038 | static void |
| 2039 | main_sigchld_handler(int sig) |
| 2040 | { |
| 2041 | int save_errno = errno; |
| 2042 | pid_t pid; |
| 2043 | int status; |
| 2044 | |
| 2045 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || |
| 2046 | (pid < 0 && errno == EINTR)) |
| 2047 | ; |
| 2048 | |
| 2049 | signal(sig, main_sigchld_handler); |
| 2050 | errno = save_errno; |
| 2051 | } |