1/* $OpenBSD: sshd-session.c,v 1.3 2024/06/06 17:15:25 djm Exp $ */ 2/* 3 * SSH2 implementation: 4 * Privilege Separation: 5 * 6 * Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved. 7 * Copyright (c) 2002 Niels Provos. All rights reserved. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30#include <sys/types.h> 31#include <sys/ioctl.h> 32#include <sys/wait.h> 33#include <sys/tree.h> 34#include <sys/stat.h> 35#include <sys/socket.h> 36#include <sys/time.h> 37#include <sys/queue.h> 38 39#include <errno.h> 40#include <fcntl.h> 41#include <netdb.h> 42#include <paths.h> 43#include <pwd.h> 44#include <signal.h> 45#include <stdio.h> 46#include <stdlib.h> 47#include <string.h> 48#include <stdarg.h> 49#include <unistd.h> 50#include <limits.h> 51 52#ifdef WITH_OPENSSL 53#include <openssl/bn.h> 54#include <openssl/evp.h> 55#endif 56 57#include "xmalloc.h" 58#include "ssh.h" 59#include "ssh2.h" 60#include "sshpty.h" 61#include "packet.h" 62#include "log.h" 63#include "sshbuf.h" 64#include "misc.h" 65#include "match.h" 66#include "servconf.h" 67#include "uidswap.h" 68#include "compat.h" 69#include "cipher.h" 70#include "digest.h" 71#include "sshkey.h" 72#include "kex.h" 73#include "authfile.h" 74#include "pathnames.h" 75#include "atomicio.h" 76#include "canohost.h" 77#include "hostfile.h" 78#include "auth.h" 79#include "authfd.h" 80#include "msg.h" 81#include "dispatch.h" 82#include "channels.h" 83#include "session.h" 84#include "monitor.h" 85#ifdef GSSAPI 86#include "ssh-gss.h" 87#endif 88#include "monitor_wrap.h" 89#include "ssh-sandbox.h" 90#include "auth-options.h" 91#include "version.h" 92#include "ssherr.h" 93#include "sk-api.h" 94#include "srclimit.h" 95#include "dh.h" 96 97/* Re-exec fds */ 98#define REEXEC_DEVCRYPTO_RESERVED_FD (STDERR_FILENO + 1) 99#define REEXEC_STARTUP_PIPE_FD (STDERR_FILENO + 2) 100#define REEXEC_CONFIG_PASS_FD (STDERR_FILENO + 3) 101#define REEXEC_MIN_FREE_FD (STDERR_FILENO + 4) 102 103extern char *__progname; 104 105/* Server configuration options. */ 106ServerOptions options; 107 108/* Name of the server configuration file. */ 109char *config_file_name = _PATH_SERVER_CONFIG_FILE; 110 111/* 112 * Debug mode flag. This can be set on the command line. If debug 113 * mode is enabled, extra debugging output will be sent to the system 114 * log, the daemon will not go to background, and will exit after processing 115 * the first connection. 116 */ 117int debug_flag = 0; 118 119/* Flag indicating that the daemon is being started from inetd. */ 120static int inetd_flag = 0; 121 122/* debug goes to stderr unless inetd_flag is set */ 123static int log_stderr = 0; 124 125/* Saved arguments to main(). */ 126static char **saved_argv; 127 128/* Daemon's agent connection */ 129int auth_sock = -1; 130static int have_agent = 0; 131 132/* 133 * Any really sensitive data in the application is contained in this 134 * structure. The idea is that this structure could be locked into memory so 135 * that the pages do not get written into swap. However, there are some 136 * problems. The private key contains BIGNUMs, and we do not (in principle) 137 * have access to the internals of them, and locking just the structure is 138 * not very useful. Currently, memory locking is not implemented. 139 */ 140struct { 141 u_int num_hostkeys; 142 struct sshkey **host_keys; /* all private host keys */ 143 struct sshkey **host_pubkeys; /* all public host keys */ 144 struct sshkey **host_certificates; /* all public host certificates */ 145} sensitive_data; 146 147/* record remote hostname or ip */ 148u_int utmp_len = HOST_NAME_MAX+1; 149 150static int startup_pipe = -1; /* in child */ 151 152/* variables used for privilege separation */ 153struct monitor *pmonitor = NULL; 154int privsep_is_preauth = 1; 155 156/* global connection state and authentication contexts */ 157Authctxt *the_authctxt = NULL; 158struct ssh *the_active_state; 159 160/* global key/cert auth options. XXX move to permanent ssh->authctxt? */ 161struct sshauthopt *auth_opts = NULL; 162 163/* sshd_config buffer */ 164struct sshbuf *cfg; 165 166/* Included files from the configuration file */ 167struct include_list includes = TAILQ_HEAD_INITIALIZER(includes); 168 169/* message to be displayed after login */ 170struct sshbuf *loginmsg; 171 172/* Prototypes for various functions defined later in this file. */ 173void destroy_sensitive_data(void); 174void demote_sensitive_data(void); 175static void do_ssh2_kex(struct ssh *); 176 177/* 178 * Signal handler for the alarm after the login grace period has expired. 179 */ 180static void 181grace_alarm_handler(int sig) 182{ 183 /* 184 * Try to kill any processes that we have spawned, E.g. authorized 185 * keys command helpers or privsep children. 186 */ 187 if (getpgid(0) == getpid()) { 188 ssh_signal(SIGTERM, SIG_IGN); 189 kill(0, SIGTERM); 190 } 191 _exit(EXIT_LOGIN_GRACE); 192} 193 194/* Destroy the host and server keys. They will no longer be needed. */ 195void 196destroy_sensitive_data(void) 197{ 198 u_int i; 199 200 for (i = 0; i < options.num_host_key_files; i++) { 201 if (sensitive_data.host_keys[i]) { 202 sshkey_free(sensitive_data.host_keys[i]); 203 sensitive_data.host_keys[i] = NULL; 204 } 205 if (sensitive_data.host_certificates[i]) { 206 sshkey_free(sensitive_data.host_certificates[i]); 207 sensitive_data.host_certificates[i] = NULL; 208 } 209 } 210} 211 212/* Demote private to public keys for network child */ 213void 214demote_sensitive_data(void) 215{ 216 struct sshkey *tmp; 217 u_int i; 218 int r; 219 220 for (i = 0; i < options.num_host_key_files; i++) { 221 if (sensitive_data.host_keys[i]) { 222 if ((r = sshkey_from_private( 223 sensitive_data.host_keys[i], &tmp)) != 0) 224 fatal_r(r, "could not demote host %s key", 225 sshkey_type(sensitive_data.host_keys[i])); 226 sshkey_free(sensitive_data.host_keys[i]); 227 sensitive_data.host_keys[i] = tmp; 228 } 229 /* Certs do not need demotion */ 230 } 231} 232 233static void 234privsep_preauth_child(void) 235{ 236 gid_t gidset[1]; 237 struct passwd *pw; 238 239 /* Enable challenge-response authentication for privilege separation */ 240 privsep_challenge_enable(); 241 242#ifdef GSSAPI 243 /* Cache supported mechanism OIDs for later use */ 244 ssh_gssapi_prepare_supported_oids(); 245#endif 246 247 /* Demote the private keys to public keys. */ 248 demote_sensitive_data(); 249 250 /* Demote the child */ 251 if (getuid() == 0 || geteuid() == 0) { 252 if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) 253 fatal("Privilege separation user %s does not exist", 254 SSH_PRIVSEP_USER); 255 pw = pwcopy(pw); /* Ensure mutable */ 256 endpwent(); 257 freezero(pw->pw_passwd, strlen(pw->pw_passwd)); 258 259 /* Change our root directory */ 260 if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1) 261 fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR, 262 strerror(errno)); 263 if (chdir("/") == -1) 264 fatal("chdir(\"/\"): %s", strerror(errno)); 265 266 /* 267 * Drop our privileges 268 * NB. Can't use setusercontext() after chroot. 269 */ 270 debug3("privsep user:group %u:%u", (u_int)pw->pw_uid, 271 (u_int)pw->pw_gid); 272 gidset[0] = pw->pw_gid; 273 if (setgroups(1, gidset) == -1) 274 fatal("setgroups: %.100s", strerror(errno)); 275 permanently_set_uid(pw); 276 } 277} 278 279static int 280privsep_preauth(struct ssh *ssh) 281{ 282 int status, r; 283 pid_t pid; 284 struct ssh_sandbox *box = NULL; 285 286 /* Set up unprivileged child process to deal with network data */ 287 pmonitor = monitor_init(); 288 /* Store a pointer to the kex for later rekeying */ 289 pmonitor->m_pkex = &ssh->kex; 290 291 box = ssh_sandbox_init(); 292 pid = fork(); 293 if (pid == -1) { 294 fatal("fork of unprivileged child failed"); 295 } else if (pid != 0) { 296 debug2("Network child is on pid %ld", (long)pid); 297 298 pmonitor->m_pid = pid; 299 if (have_agent) { 300 r = ssh_get_authentication_socket(&auth_sock); 301 if (r != 0) { 302 error_r(r, "Could not get agent socket"); 303 have_agent = 0; 304 } 305 } 306 if (box != NULL) 307 ssh_sandbox_parent_preauth(box, pid); 308 monitor_child_preauth(ssh, pmonitor); 309 310 /* Wait for the child's exit status */ 311 while (waitpid(pid, &status, 0) == -1) { 312 if (errno == EINTR) 313 continue; 314 pmonitor->m_pid = -1; 315 fatal_f("waitpid: %s", strerror(errno)); 316 } 317 privsep_is_preauth = 0; 318 pmonitor->m_pid = -1; 319 if (WIFEXITED(status)) { 320 if (WEXITSTATUS(status) != 0) 321 fatal_f("preauth child exited with status %d", 322 WEXITSTATUS(status)); 323 } else if (WIFSIGNALED(status)) 324 fatal_f("preauth child terminated by signal %d", 325 WTERMSIG(status)); 326 if (box != NULL) 327 ssh_sandbox_parent_finish(box); 328 return 1; 329 } else { 330 /* child */ 331 close(pmonitor->m_sendfd); 332 close(pmonitor->m_log_recvfd); 333 334 /* Arrange for logging to be sent to the monitor */ 335 set_log_handler(mm_log_handler, pmonitor); 336 337 privsep_preauth_child(); 338 setproctitle("%s", "[net]"); 339 if (box != NULL) 340 ssh_sandbox_child(box); 341 342 return 0; 343 } 344} 345 346static void 347privsep_postauth(struct ssh *ssh, Authctxt *authctxt) 348{ 349 /* New socket pair */ 350 monitor_reinit(pmonitor); 351 352 pmonitor->m_pid = fork(); 353 if (pmonitor->m_pid == -1) 354 fatal("fork of unprivileged child failed"); 355 else if (pmonitor->m_pid != 0) { 356 verbose("User child is on pid %ld", (long)pmonitor->m_pid); 357 sshbuf_reset(loginmsg); 358 monitor_clear_keystate(ssh, pmonitor); 359 monitor_child_postauth(ssh, pmonitor); 360 361 /* NEVERREACHED */ 362 exit(0); 363 } 364 365 /* child */ 366 367 close(pmonitor->m_sendfd); 368 pmonitor->m_sendfd = -1; 369 370 /* Demote the private keys to public keys. */ 371 demote_sensitive_data(); 372 373 /* Drop privileges */ 374 do_setusercontext(authctxt->pw); 375 376 /* It is safe now to apply the key state */ 377 monitor_apply_keystate(ssh, pmonitor); 378 379 /* 380 * Tell the packet layer that authentication was successful, since 381 * this information is not part of the key state. 382 */ 383 ssh_packet_set_authenticated(ssh); 384} 385 386static void 387append_hostkey_type(struct sshbuf *b, const char *s) 388{ 389 int r; 390 391 if (match_pattern_list(s, options.hostkeyalgorithms, 0) != 1) { 392 debug3_f("%s key not permitted by HostkeyAlgorithms", s); 393 return; 394 } 395 if ((r = sshbuf_putf(b, "%s%s", sshbuf_len(b) > 0 ? "," : "", s)) != 0) 396 fatal_fr(r, "sshbuf_putf"); 397} 398 399static char * 400list_hostkey_types(void) 401{ 402 struct sshbuf *b; 403 struct sshkey *key; 404 char *ret; 405 u_int i; 406 407 if ((b = sshbuf_new()) == NULL) 408 fatal_f("sshbuf_new failed"); 409 for (i = 0; i < options.num_host_key_files; i++) { 410 key = sensitive_data.host_keys[i]; 411 if (key == NULL) 412 key = sensitive_data.host_pubkeys[i]; 413 if (key == NULL) 414 continue; 415 switch (key->type) { 416 case KEY_RSA: 417 /* for RSA we also support SHA2 signatures */ 418 append_hostkey_type(b, "rsa-sha2-512"); 419 append_hostkey_type(b, "rsa-sha2-256"); 420 /* FALLTHROUGH */ 421 case KEY_DSA: 422 case KEY_ECDSA: 423 case KEY_ED25519: 424 case KEY_ECDSA_SK: 425 case KEY_ED25519_SK: 426 case KEY_XMSS: 427 append_hostkey_type(b, sshkey_ssh_name(key)); 428 break; 429 } 430 /* If the private key has a cert peer, then list that too */ 431 key = sensitive_data.host_certificates[i]; 432 if (key == NULL) 433 continue; 434 switch (key->type) { 435 case KEY_RSA_CERT: 436 /* for RSA we also support SHA2 signatures */ 437 append_hostkey_type(b, 438 "rsa-sha2-512-cert-v01@openssh.com"); 439 append_hostkey_type(b, 440 "rsa-sha2-256-cert-v01@openssh.com"); 441 /* FALLTHROUGH */ 442 case KEY_DSA_CERT: 443 case KEY_ECDSA_CERT: 444 case KEY_ED25519_CERT: 445 case KEY_ECDSA_SK_CERT: 446 case KEY_ED25519_SK_CERT: 447 case KEY_XMSS_CERT: 448 append_hostkey_type(b, sshkey_ssh_name(key)); 449 break; 450 } 451 } 452 if ((ret = sshbuf_dup_string(b)) == NULL) 453 fatal_f("sshbuf_dup_string failed"); 454 sshbuf_free(b); 455 debug_f("%s", ret); 456 return ret; 457} 458 459static struct sshkey * 460get_hostkey_by_type(int type, int nid, int need_private, struct ssh *ssh) 461{ 462 u_int i; 463 struct sshkey *key; 464 465 for (i = 0; i < options.num_host_key_files; i++) { 466 switch (type) { 467 case KEY_RSA_CERT: 468 case KEY_DSA_CERT: 469 case KEY_ECDSA_CERT: 470 case KEY_ED25519_CERT: 471 case KEY_ECDSA_SK_CERT: 472 case KEY_ED25519_SK_CERT: 473 case KEY_XMSS_CERT: 474 key = sensitive_data.host_certificates[i]; 475 break; 476 default: 477 key = sensitive_data.host_keys[i]; 478 if (key == NULL && !need_private) 479 key = sensitive_data.host_pubkeys[i]; 480 break; 481 } 482 if (key == NULL || key->type != type) 483 continue; 484 switch (type) { 485 case KEY_ECDSA: 486 case KEY_ECDSA_SK: 487 case KEY_ECDSA_CERT: 488 case KEY_ECDSA_SK_CERT: 489 if (key->ecdsa_nid != nid) 490 continue; 491 /* FALLTHROUGH */ 492 default: 493 return need_private ? 494 sensitive_data.host_keys[i] : key; 495 } 496 } 497 return NULL; 498} 499 500struct sshkey * 501get_hostkey_public_by_type(int type, int nid, struct ssh *ssh) 502{ 503 return get_hostkey_by_type(type, nid, 0, ssh); 504} 505 506struct sshkey * 507get_hostkey_private_by_type(int type, int nid, struct ssh *ssh) 508{ 509 return get_hostkey_by_type(type, nid, 1, ssh); 510} 511 512struct sshkey * 513get_hostkey_by_index(int ind) 514{ 515 if (ind < 0 || (u_int)ind >= options.num_host_key_files) 516 return (NULL); 517 return (sensitive_data.host_keys[ind]); 518} 519 520struct sshkey * 521get_hostkey_public_by_index(int ind, struct ssh *ssh) 522{ 523 if (ind < 0 || (u_int)ind >= options.num_host_key_files) 524 return (NULL); 525 return (sensitive_data.host_pubkeys[ind]); 526} 527 528int 529get_hostkey_index(struct sshkey *key, int compare, struct ssh *ssh) 530{ 531 u_int i; 532 533 for (i = 0; i < options.num_host_key_files; i++) { 534 if (sshkey_is_cert(key)) { 535 if (key == sensitive_data.host_certificates[i] || 536 (compare && sensitive_data.host_certificates[i] && 537 sshkey_equal(key, 538 sensitive_data.host_certificates[i]))) 539 return (i); 540 } else { 541 if (key == sensitive_data.host_keys[i] || 542 (compare && sensitive_data.host_keys[i] && 543 sshkey_equal(key, sensitive_data.host_keys[i]))) 544 return (i); 545 if (key == sensitive_data.host_pubkeys[i] || 546 (compare && sensitive_data.host_pubkeys[i] && 547 sshkey_equal(key, sensitive_data.host_pubkeys[i]))) 548 return (i); 549 } 550 } 551 return (-1); 552} 553 554/* Inform the client of all hostkeys */ 555static void 556notify_hostkeys(struct ssh *ssh) 557{ 558 struct sshbuf *buf; 559 struct sshkey *key; 560 u_int i, nkeys; 561 int r; 562 char *fp; 563 564 /* Some clients cannot cope with the hostkeys message, skip those. */ 565 if (ssh->compat & SSH_BUG_HOSTKEYS) 566 return; 567 568 if ((buf = sshbuf_new()) == NULL) 569 fatal_f("sshbuf_new"); 570 for (i = nkeys = 0; i < options.num_host_key_files; i++) { 571 key = get_hostkey_public_by_index(i, ssh); 572 if (key == NULL || key->type == KEY_UNSPEC || 573 sshkey_is_cert(key)) 574 continue; 575 fp = sshkey_fingerprint(key, options.fingerprint_hash, 576 SSH_FP_DEFAULT); 577 debug3_f("key %d: %s %s", i, sshkey_ssh_name(key), fp); 578 free(fp); 579 if (nkeys == 0) { 580 /* 581 * Start building the request when we find the 582 * first usable key. 583 */ 584 if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 || 585 (r = sshpkt_put_cstring(ssh, "hostkeys-00@openssh.com")) != 0 || 586 (r = sshpkt_put_u8(ssh, 0)) != 0) /* want reply */ 587 sshpkt_fatal(ssh, r, "%s: start request", __func__); 588 } 589 /* Append the key to the request */ 590 sshbuf_reset(buf); 591 if ((r = sshkey_putb(key, buf)) != 0) 592 fatal_fr(r, "couldn't put hostkey %d", i); 593 if ((r = sshpkt_put_stringb(ssh, buf)) != 0) 594 sshpkt_fatal(ssh, r, "%s: append key", __func__); 595 nkeys++; 596 } 597 debug3_f("sent %u hostkeys", nkeys); 598 if (nkeys == 0) 599 fatal_f("no hostkeys"); 600 if ((r = sshpkt_send(ssh)) != 0) 601 sshpkt_fatal(ssh, r, "%s: send", __func__); 602 sshbuf_free(buf); 603} 604 605static void 606usage(void) 607{ 608 fprintf(stderr, "%s, %s\n", SSH_VERSION, SSH_OPENSSL_VERSION); 609 fprintf(stderr, 610"usage: sshd [-46DdeGiqTtV] [-C connection_spec] [-c host_cert_file]\n" 611" [-E log_file] [-f config_file] [-g login_grace_time]\n" 612" [-h host_key_file] [-o option] [-p port] [-u len]\n" 613 ); 614 exit(1); 615} 616 617static void 618parse_hostkeys(struct sshbuf *hostkeys) 619{ 620 int r; 621 u_int num_keys = 0; 622 struct sshkey *k; 623 struct sshbuf *kbuf; 624 const u_char *cp; 625 size_t len; 626 627 while (sshbuf_len(hostkeys) != 0) { 628 if (num_keys > 2048) 629 fatal_f("too many hostkeys"); 630 sensitive_data.host_keys = xrecallocarray( 631 sensitive_data.host_keys, num_keys, num_keys + 1, 632 sizeof(*sensitive_data.host_pubkeys)); 633 sensitive_data.host_pubkeys = xrecallocarray( 634 sensitive_data.host_pubkeys, num_keys, num_keys + 1, 635 sizeof(*sensitive_data.host_pubkeys)); 636 sensitive_data.host_certificates = xrecallocarray( 637 sensitive_data.host_certificates, num_keys, num_keys + 1, 638 sizeof(*sensitive_data.host_certificates)); 639 /* private key */ 640 k = NULL; 641 if ((r = sshbuf_froms(hostkeys, &kbuf)) != 0) 642 fatal_fr(r, "extract privkey"); 643 if (sshbuf_len(kbuf) != 0 && 644 (r = sshkey_private_deserialize(kbuf, &k)) != 0) 645 fatal_fr(r, "parse pubkey"); 646 sensitive_data.host_keys[num_keys] = k; 647 sshbuf_free(kbuf); 648 if (k) 649 debug2_f("privkey %u: %s", num_keys, sshkey_ssh_name(k)); 650 /* public key */ 651 k = NULL; 652 if ((r = sshbuf_get_string_direct(hostkeys, &cp, &len)) != 0) 653 fatal_fr(r, "extract pubkey"); 654 if (len != 0 && (r = sshkey_from_blob(cp, len, &k)) != 0) 655 fatal_fr(r, "parse pubkey"); 656 sensitive_data.host_pubkeys[num_keys] = k; 657 if (k) 658 debug2_f("pubkey %u: %s", num_keys, sshkey_ssh_name(k)); 659 /* certificate */ 660 k = NULL; 661 if ((r = sshbuf_get_string_direct(hostkeys, &cp, &len)) != 0) 662 fatal_fr(r, "extract pubkey"); 663 if (len != 0 && (r = sshkey_from_blob(cp, len, &k)) != 0) 664 fatal_fr(r, "parse pubkey"); 665 sensitive_data.host_certificates[num_keys] = k; 666 if (k) 667 debug2_f("cert %u: %s", num_keys, sshkey_ssh_name(k)); 668 num_keys++; 669 } 670 sensitive_data.num_hostkeys = num_keys; 671} 672 673static void 674recv_rexec_state(int fd, struct sshbuf *conf, uint64_t *timing_secretp) 675{ 676 struct sshbuf *m, *inc, *hostkeys; 677 u_char *cp, ver; 678 size_t len; 679 int r; 680 struct include_item *item; 681 682 debug3_f("entering fd = %d", fd); 683 684 if ((m = sshbuf_new()) == NULL || (inc = sshbuf_new()) == NULL) 685 fatal_f("sshbuf_new failed"); 686 if (ssh_msg_recv(fd, m) == -1) 687 fatal_f("ssh_msg_recv failed"); 688 if ((r = sshbuf_get_u8(m, &ver)) != 0) 689 fatal_fr(r, "parse version"); 690 if (ver != 0) 691 fatal_f("rexec version mismatch"); 692 if ((r = sshbuf_get_string(m, &cp, &len)) != 0 || /* XXX _direct */ 693 (r = sshbuf_get_u64(m, timing_secretp)) != 0 || 694 (r = sshbuf_froms(m, &hostkeys)) != 0 || 695 (r = sshbuf_get_stringb(m, inc)) != 0) 696 fatal_fr(r, "parse config"); 697 698 if (conf != NULL && (r = sshbuf_put(conf, cp, len))) 699 fatal_fr(r, "sshbuf_put"); 700 701 while (sshbuf_len(inc) != 0) { 702 item = xcalloc(1, sizeof(*item)); 703 if ((item->contents = sshbuf_new()) == NULL) 704 fatal_f("sshbuf_new failed"); 705 if ((r = sshbuf_get_cstring(inc, &item->selector, NULL)) != 0 || 706 (r = sshbuf_get_cstring(inc, &item->filename, NULL)) != 0 || 707 (r = sshbuf_get_stringb(inc, item->contents)) != 0) 708 fatal_fr(r, "parse includes"); 709 TAILQ_INSERT_TAIL(&includes, item, entry); 710 } 711 712 parse_hostkeys(hostkeys); 713 714 free(cp); 715 sshbuf_free(m); 716 sshbuf_free(hostkeys); 717 sshbuf_free(inc); 718 719 debug3_f("done"); 720} 721 722/* 723 * If IP options are supported, make sure there are none (log and 724 * return an error if any are found). Basically we are worried about 725 * source routing; it can be used to pretend you are somebody 726 * (ip-address) you are not. That itself may be "almost acceptable" 727 * under certain circumstances, but rhosts authentication is useless 728 * if source routing is accepted. Notice also that if we just dropped 729 * source routing here, the other side could use IP spoofing to do 730 * rest of the interaction and could still bypass security. So we 731 * exit here if we detect any IP options. 732 */ 733static void 734check_ip_options(struct ssh *ssh) 735{ 736 int sock_in = ssh_packet_get_connection_in(ssh); 737 struct sockaddr_storage from; 738 u_char opts[200]; 739 socklen_t i, option_size = sizeof(opts), fromlen = sizeof(from); 740 char text[sizeof(opts) * 3 + 1]; 741 742 memset(&from, 0, sizeof(from)); 743 if (getpeername(sock_in, (struct sockaddr *)&from, 744 &fromlen) == -1) 745 return; 746 if (from.ss_family != AF_INET) 747 return; 748 /* XXX IPv6 options? */ 749 750 if (getsockopt(sock_in, IPPROTO_IP, IP_OPTIONS, opts, 751 &option_size) >= 0 && option_size != 0) { 752 text[0] = '\0'; 753 for (i = 0; i < option_size; i++) 754 snprintf(text + i*3, sizeof(text) - i*3, 755 " %2.2x", opts[i]); 756 fatal("Connection from %.100s port %d with IP opts: %.800s", 757 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), text); 758 } 759 return; 760} 761 762/* Set the routing domain for this process */ 763static void 764set_process_rdomain(struct ssh *ssh, const char *name) 765{ 766 int rtable, ortable = getrtable(); 767 const char *errstr; 768 769 if (name == NULL) 770 return; /* default */ 771 772 if (strcmp(name, "%D") == 0) { 773 /* "expands" to routing domain of connection */ 774 if ((name = ssh_packet_rdomain_in(ssh)) == NULL) 775 return; 776 } 777 778 rtable = (int)strtonum(name, 0, 255, &errstr); 779 if (errstr != NULL) /* Shouldn't happen */ 780 fatal("Invalid routing domain \"%s\": %s", name, errstr); 781 if (rtable != ortable && setrtable(rtable) != 0) 782 fatal("Unable to set routing domain %d: %s", 783 rtable, strerror(errno)); 784 debug_f("set routing domain %d (was %d)", rtable, ortable); 785} 786 787/* 788 * Main program for the daemon. 789 */ 790int 791main(int ac, char **av) 792{ 793 struct ssh *ssh = NULL; 794 extern char *optarg; 795 extern int optind; 796 int r, opt, on = 1, remote_port; 797 int sock_in = -1, sock_out = -1, rexeced_flag = 0, have_key = 0; 798 const char *remote_ip, *rdomain; 799 char *line, *laddr, *logfile = NULL; 800 u_int i; 801 u_int64_t ibytes, obytes; 802 mode_t new_umask; 803 Authctxt *authctxt; 804 struct connection_info *connection_info = NULL; 805 sigset_t sigmask; 806 uint64_t timing_secret = 0; 807 808 sigemptyset(&sigmask); 809 sigprocmask(SIG_SETMASK, &sigmask, NULL); 810 811 /* Save argv. */ 812 saved_argv = av; 813 814 /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ 815 sanitise_stdfd(); 816 817 /* Initialize configuration options to their default values. */ 818 initialize_server_options(&options); 819 820 /* Parse command-line arguments. */ 821 while ((opt = getopt(ac, av, 822 "C:E:b:c:f:g:h:k:o:p:u:46DGQRTdeiqrtV")) != -1) { 823 switch (opt) { 824 case '4': 825 options.address_family = AF_INET; 826 break; 827 case '6': 828 options.address_family = AF_INET6; 829 break; 830 case 'f': 831 config_file_name = optarg; 832 break; 833 case 'c': 834 servconf_add_hostcert("[command-line]", 0, 835 &options, optarg); 836 break; 837 case 'd': 838 if (debug_flag == 0) { 839 debug_flag = 1; 840 options.log_level = SYSLOG_LEVEL_DEBUG1; 841 } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) 842 options.log_level++; 843 break; 844 case 'D': 845 /* ignore */ 846 break; 847 case 'E': 848 logfile = optarg; 849 /* FALLTHROUGH */ 850 case 'e': 851 log_stderr = 1; 852 break; 853 case 'i': 854 inetd_flag = 1; 855 break; 856 case 'r': 857 /* ignore */ 858 break; 859 case 'R': 860 rexeced_flag = 1; 861 break; 862 case 'Q': 863 /* ignored */ 864 break; 865 case 'q': 866 options.log_level = SYSLOG_LEVEL_QUIET; 867 break; 868 case 'b': 869 /* protocol 1, ignored */ 870 break; 871 case 'p': 872 options.ports_from_cmdline = 1; 873 if (options.num_ports >= MAX_PORTS) { 874 fprintf(stderr, "too many ports.\n"); 875 exit(1); 876 } 877 options.ports[options.num_ports++] = a2port(optarg); 878 if (options.ports[options.num_ports-1] <= 0) { 879 fprintf(stderr, "Bad port number.\n"); 880 exit(1); 881 } 882 break; 883 case 'g': 884 if ((options.login_grace_time = convtime(optarg)) == -1) { 885 fprintf(stderr, "Invalid login grace time.\n"); 886 exit(1); 887 } 888 break; 889 case 'k': 890 /* protocol 1, ignored */ 891 break; 892 case 'h': 893 servconf_add_hostkey("[command-line]", 0, 894 &options, optarg, 1); 895 break; 896 case 't': 897 case 'T': 898 case 'G': 899 fatal("test/dump modes not supported"); 900 break; 901 case 'C': 902 connection_info = server_get_connection_info(ssh, 0, 0); 903 if (parse_server_match_testspec(connection_info, 904 optarg) == -1) 905 exit(1); 906 break; 907 case 'u': 908 utmp_len = (u_int)strtonum(optarg, 0, HOST_NAME_MAX+1+1, NULL); 909 if (utmp_len > HOST_NAME_MAX+1) { 910 fprintf(stderr, "Invalid utmp length.\n"); 911 exit(1); 912 } 913 break; 914 case 'o': 915 line = xstrdup(optarg); 916 if (process_server_config_line(&options, line, 917 "command-line", 0, NULL, NULL, &includes) != 0) 918 exit(1); 919 free(line); 920 break; 921 case 'V': 922 fprintf(stderr, "%s, %s\n", 923 SSH_VERSION, SSH_OPENSSL_VERSION); 924 exit(0); 925 default: 926 usage(); 927 break; 928 } 929 } 930 931 /* Check that there are no remaining arguments. */ 932 if (optind < ac) { 933 fprintf(stderr, "Extra argument %s.\n", av[optind]); 934 exit(1); 935 } 936 937 debug("sshd version %s, %s", SSH_VERSION, SSH_OPENSSL_VERSION); 938 939 if (!rexeced_flag) 940 fatal("sshd-session should not be executed directly"); 941 942 closefrom(REEXEC_MIN_FREE_FD); 943 944#ifdef WITH_OPENSSL 945 OpenSSL_add_all_algorithms(); 946#endif 947 948 /* If requested, redirect the logs to the specified logfile. */ 949 if (logfile != NULL) { 950 char *cp, pid_s[32]; 951 952 snprintf(pid_s, sizeof(pid_s), "%ld", (unsigned long)getpid()); 953 cp = percent_expand(logfile, 954 "p", pid_s, 955 "P", "sshd-session", 956 (char *)NULL); 957 log_redirect_stderr_to(cp); 958 free(cp); 959 } 960 961 /* 962 * Force logging to stderr until we have loaded the private host 963 * key (unless started from inetd) 964 */ 965 log_init(__progname, 966 options.log_level == SYSLOG_LEVEL_NOT_SET ? 967 SYSLOG_LEVEL_INFO : options.log_level, 968 options.log_facility == SYSLOG_FACILITY_NOT_SET ? 969 SYSLOG_FACILITY_AUTH : options.log_facility, 970 log_stderr || !inetd_flag || debug_flag); 971 972 debug("sshd version %s, %s", SSH_VERSION, SSH_OPENSSL_VERSION); 973 974 /* Fetch our configuration */ 975 if ((cfg = sshbuf_new()) == NULL) 976 fatal("sshbuf_new config buf failed"); 977 setproctitle("%s", "[rexeced]"); 978 recv_rexec_state(REEXEC_CONFIG_PASS_FD, cfg, &timing_secret); 979 close(REEXEC_CONFIG_PASS_FD); 980 parse_server_config(&options, "rexec", cfg, &includes, NULL, 1); 981 /* Fill in default values for those options not explicitly set. */ 982 fill_default_server_options(&options); 983 options.timing_secret = timing_secret; 984 985 if (!debug_flag) { 986 startup_pipe = dup(REEXEC_STARTUP_PIPE_FD); 987 close(REEXEC_STARTUP_PIPE_FD); 988 /* 989 * Signal parent that this child is at a point where 990 * they can go away if they have a SIGHUP pending. 991 */ 992 (void)atomicio(vwrite, startup_pipe, "\0", 1); 993 } 994 995 /* Check that options are sensible */ 996 if (options.authorized_keys_command_user == NULL && 997 (options.authorized_keys_command != NULL && 998 strcasecmp(options.authorized_keys_command, "none") != 0)) 999 fatal("AuthorizedKeysCommand set without " 1000 "AuthorizedKeysCommandUser"); 1001 if (options.authorized_principals_command_user == NULL && 1002 (options.authorized_principals_command != NULL && 1003 strcasecmp(options.authorized_principals_command, "none") != 0)) 1004 fatal("AuthorizedPrincipalsCommand set without " 1005 "AuthorizedPrincipalsCommandUser"); 1006 1007 /* 1008 * Check whether there is any path through configured auth methods. 1009 * Unfortunately it is not possible to verify this generally before 1010 * daemonisation in the presence of Match block, but this catches 1011 * and warns for trivial misconfigurations that could break login. 1012 */ 1013 if (options.num_auth_methods != 0) { 1014 for (i = 0; i < options.num_auth_methods; i++) { 1015 if (auth2_methods_valid(options.auth_methods[i], 1016 1) == 0) 1017 break; 1018 } 1019 if (i >= options.num_auth_methods) 1020 fatal("AuthenticationMethods cannot be satisfied by " 1021 "enabled authentication methods"); 1022 } 1023 1024#ifdef WITH_OPENSSL 1025 if (options.moduli_file != NULL) 1026 dh_set_moduli_file(options.moduli_file); 1027#endif 1028 1029 if (options.host_key_agent) { 1030 if (strcmp(options.host_key_agent, SSH_AUTHSOCKET_ENV_NAME)) 1031 setenv(SSH_AUTHSOCKET_ENV_NAME, 1032 options.host_key_agent, 1); 1033 if ((r = ssh_get_authentication_socket(NULL)) == 0) 1034 have_agent = 1; 1035 else 1036 error_r(r, "Could not connect to agent \"%s\"", 1037 options.host_key_agent); 1038 } 1039 1040 if (options.num_host_key_files != sensitive_data.num_hostkeys) { 1041 fatal("internal error: hostkeys confused (config %u recvd %u)", 1042 options.num_host_key_files, sensitive_data.num_hostkeys); 1043 } 1044 1045 for (i = 0; i < options.num_host_key_files; i++) { 1046 if (sensitive_data.host_keys[i] != NULL || 1047 (have_agent && sensitive_data.host_pubkeys[i] != NULL)) { 1048 have_key = 1; 1049 break; 1050 } 1051 } 1052 if (!have_key) 1053 fatal("internal error: monitor received no hostkeys"); 1054 1055 /* Ensure that umask disallows at least group and world write */ 1056 new_umask = umask(0077) | 0022; 1057 (void) umask(new_umask); 1058 1059 /* Initialize the log (it is reinitialized below in case we forked). */ 1060 if (debug_flag) 1061 log_stderr = 1; 1062 log_init(__progname, options.log_level, 1063 options.log_facility, log_stderr); 1064 for (i = 0; i < options.num_log_verbose; i++) 1065 log_verbose_add(options.log_verbose[i]); 1066 1067 /* Reinitialize the log (because of the fork above). */ 1068 log_init(__progname, options.log_level, options.log_facility, log_stderr); 1069 1070 /* 1071 * Chdir to the root directory so that the current disk can be 1072 * unmounted if desired. 1073 */ 1074 if (chdir("/") == -1) 1075 error("chdir(\"/\"): %s", strerror(errno)); 1076 1077 /* ignore SIGPIPE */ 1078 ssh_signal(SIGPIPE, SIG_IGN); 1079 1080 /* Get a connection, either from inetd or rexec */ 1081 if (inetd_flag) { 1082 /* 1083 * NB. must be different fd numbers for the !socket case, 1084 * as packet_connection_is_on_socket() depends on this. 1085 */ 1086 sock_in = dup(STDIN_FILENO); 1087 sock_out = dup(STDOUT_FILENO); 1088 } else { 1089 /* rexec case; accept()ed socket in ancestor listener */ 1090 sock_in = sock_out = dup(STDIN_FILENO); 1091 } 1092 1093 /* 1094 * We intentionally do not close the descriptors 0, 1, and 2 1095 * as our code for setting the descriptors won't work if 1096 * ttyfd happens to be one of those. 1097 */ 1098 if (stdfd_devnull(1, 1, !log_stderr) == -1) 1099 error("stdfd_devnull failed"); 1100 debug("network sockets: %d, %d", sock_in, sock_out); 1101 1102 /* This is the child processing a new connection. */ 1103 setproctitle("%s", "[accepted]"); 1104 1105 /* Executed child processes don't need these. */ 1106 fcntl(sock_out, F_SETFD, FD_CLOEXEC); 1107 fcntl(sock_in, F_SETFD, FD_CLOEXEC); 1108 1109 /* We will not restart on SIGHUP since it no longer makes sense. */ 1110 ssh_signal(SIGALRM, SIG_DFL); 1111 ssh_signal(SIGHUP, SIG_DFL); 1112 ssh_signal(SIGTERM, SIG_DFL); 1113 ssh_signal(SIGQUIT, SIG_DFL); 1114 ssh_signal(SIGCHLD, SIG_DFL); 1115 1116 /* 1117 * Register our connection. This turns encryption off because we do 1118 * not have a key. 1119 */ 1120 if ((ssh = ssh_packet_set_connection(NULL, sock_in, sock_out)) == NULL) 1121 fatal("Unable to create connection"); 1122 the_active_state = ssh; 1123 ssh_packet_set_server(ssh); 1124 1125 check_ip_options(ssh); 1126 1127 /* Prepare the channels layer */ 1128 channel_init_channels(ssh); 1129 channel_set_af(ssh, options.address_family); 1130 server_process_channel_timeouts(ssh); 1131 server_process_permitopen(ssh); 1132 1133 /* Set SO_KEEPALIVE if requested. */ 1134 if (options.tcp_keep_alive && ssh_packet_connection_is_on_socket(ssh) && 1135 setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof(on)) == -1) 1136 error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); 1137 1138 if ((remote_port = ssh_remote_port(ssh)) < 0) { 1139 debug("ssh_remote_port failed"); 1140 cleanup_exit(255); 1141 } 1142 1143 /* 1144 * The rest of the code depends on the fact that 1145 * ssh_remote_ipaddr() caches the remote ip, even if 1146 * the socket goes away. 1147 */ 1148 remote_ip = ssh_remote_ipaddr(ssh); 1149 1150 rdomain = ssh_packet_rdomain_in(ssh); 1151 1152 /* Log the connection. */ 1153 laddr = get_local_ipaddr(sock_in); 1154 verbose("Connection from %s port %d on %s port %d%s%s%s", 1155 remote_ip, remote_port, laddr, ssh_local_port(ssh), 1156 rdomain == NULL ? "" : " rdomain \"", 1157 rdomain == NULL ? "" : rdomain, 1158 rdomain == NULL ? "" : "\""); 1159 free(laddr); 1160 1161 /* 1162 * We don't want to listen forever unless the other side 1163 * successfully authenticates itself. So we set up an alarm which is 1164 * cleared after successful authentication. A limit of zero 1165 * indicates no limit. Note that we don't set the alarm in debugging 1166 * mode; it is just annoying to have the server exit just when you 1167 * are about to discover the bug. 1168 */ 1169 ssh_signal(SIGALRM, grace_alarm_handler); 1170 if (!debug_flag) 1171 alarm(options.login_grace_time); 1172 1173 if ((r = kex_exchange_identification(ssh, -1, 1174 options.version_addendum)) != 0) 1175 sshpkt_fatal(ssh, r, "banner exchange"); 1176 1177 ssh_packet_set_nonblocking(ssh); 1178 1179 /* allocate authentication context */ 1180 authctxt = xcalloc(1, sizeof(*authctxt)); 1181 ssh->authctxt = authctxt; 1182 1183 /* XXX global for cleanup, access from other modules */ 1184 the_authctxt = authctxt; 1185 1186 /* Set default key authentication options */ 1187 if ((auth_opts = sshauthopt_new_with_keys_defaults()) == NULL) 1188 fatal("allocation failed"); 1189 1190 /* prepare buffer to collect messages to display to user after login */ 1191 if ((loginmsg = sshbuf_new()) == NULL) 1192 fatal("sshbuf_new loginmsg failed"); 1193 auth_debug_reset(); 1194 1195 if (privsep_preauth(ssh) == 1) 1196 goto authenticated; 1197 1198 /* perform the key exchange */ 1199 /* authenticate user and start session */ 1200 do_ssh2_kex(ssh); 1201 do_authentication2(ssh); 1202 1203 /* 1204 * The unprivileged child now transfers the current keystate and exits. 1205 */ 1206 mm_send_keystate(ssh, pmonitor); 1207 ssh_packet_clear_keys(ssh); 1208 exit(0); 1209 1210 authenticated: 1211 /* 1212 * Cancel the alarm we set to limit the time taken for 1213 * authentication. 1214 */ 1215 alarm(0); 1216 ssh_signal(SIGALRM, SIG_DFL); 1217 authctxt->authenticated = 1; 1218 if (startup_pipe != -1) { 1219 /* signal listener that authentication completed successfully */ 1220 (void)atomicio(vwrite, startup_pipe, "\001", 1); 1221 close(startup_pipe); 1222 startup_pipe = -1; 1223 } 1224 1225 if (options.routing_domain != NULL) 1226 set_process_rdomain(ssh, options.routing_domain); 1227 1228 /* 1229 * In privilege separation, we fork another child and prepare 1230 * file descriptor passing. 1231 */ 1232 privsep_postauth(ssh, authctxt); 1233 /* the monitor process [priv] will not return */ 1234 1235 ssh_packet_set_timeout(ssh, options.client_alive_interval, 1236 options.client_alive_count_max); 1237 1238 /* Try to send all our hostkeys to the client */ 1239 notify_hostkeys(ssh); 1240 1241 /* Start session. */ 1242 do_authenticated(ssh, authctxt); 1243 1244 /* The connection has been terminated. */ 1245 ssh_packet_get_bytes(ssh, &ibytes, &obytes); 1246 verbose("Transferred: sent %llu, received %llu bytes", 1247 (unsigned long long)obytes, (unsigned long long)ibytes); 1248 1249 verbose("Closing connection to %.500s port %d", remote_ip, remote_port); 1250 ssh_packet_close(ssh); 1251 1252 mm_terminate(); 1253 1254 exit(0); 1255} 1256 1257int 1258sshd_hostkey_sign(struct ssh *ssh, struct sshkey *privkey, 1259 struct sshkey *pubkey, u_char **signature, size_t *slenp, 1260 const u_char *data, size_t dlen, const char *alg) 1261{ 1262 if (privkey) { 1263 if (mm_sshkey_sign(ssh, privkey, signature, slenp, 1264 data, dlen, alg, options.sk_provider, NULL, 1265 ssh->compat) < 0) 1266 fatal_f("privkey sign failed"); 1267 } else { 1268 if (mm_sshkey_sign(ssh, pubkey, signature, slenp, 1269 data, dlen, alg, options.sk_provider, NULL, 1270 ssh->compat) < 0) 1271 fatal_f("pubkey sign failed"); 1272 } 1273 return 0; 1274} 1275 1276/* SSH2 key exchange */ 1277static void 1278do_ssh2_kex(struct ssh *ssh) 1279{ 1280 char *hkalgs = NULL, *myproposal[PROPOSAL_MAX]; 1281 const char *compression = NULL; 1282 struct kex *kex; 1283 int r; 1284 1285 if (options.rekey_limit || options.rekey_interval) 1286 ssh_packet_set_rekey_limits(ssh, options.rekey_limit, 1287 options.rekey_interval); 1288 1289 if (options.compression == COMP_NONE) 1290 compression = "none"; 1291 hkalgs = list_hostkey_types(); 1292 1293 kex_proposal_populate_entries(ssh, myproposal, options.kex_algorithms, 1294 options.ciphers, options.macs, compression, hkalgs); 1295 1296 free(hkalgs); 1297 1298 /* start key exchange */ 1299 if ((r = kex_setup(ssh, myproposal)) != 0) 1300 fatal_r(r, "kex_setup"); 1301 kex_set_server_sig_algs(ssh, options.pubkey_accepted_algos); 1302 kex = ssh->kex; 1303 1304#ifdef WITH_OPENSSL 1305 kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server; 1306 kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server; 1307 kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server; 1308 kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server; 1309 kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server; 1310 kex->kex[KEX_DH_GEX_SHA1] = kexgex_server; 1311 kex->kex[KEX_DH_GEX_SHA256] = kexgex_server; 1312 kex->kex[KEX_ECDH_SHA2] = kex_gen_server; 1313#endif 1314 kex->kex[KEX_C25519_SHA256] = kex_gen_server; 1315 kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server; 1316 kex->load_host_public_key=&get_hostkey_public_by_type; 1317 kex->load_host_private_key=&get_hostkey_private_by_type; 1318 kex->host_key_index=&get_hostkey_index; 1319 kex->sign = sshd_hostkey_sign; 1320 1321 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &kex->done); 1322 kex_proposal_free_entries(myproposal); 1323 1324#ifdef DEBUG_KEXDH 1325 /* send 1st encrypted/maced/compressed message */ 1326 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 || 1327 (r = sshpkt_put_cstring(ssh, "markus")) != 0 || 1328 (r = sshpkt_send(ssh)) != 0 || 1329 (r = ssh_packet_write_wait(ssh)) != 0) 1330 fatal_fr(r, "send test"); 1331#endif 1332 debug("KEX done"); 1333} 1334 1335/* server specific fatal cleanup */ 1336void 1337cleanup_exit(int i) 1338{ 1339 extern int auth_attempted; /* monitor.c */ 1340 1341 if (the_active_state != NULL && the_authctxt != NULL) { 1342 do_cleanup(the_active_state, the_authctxt); 1343 if (privsep_is_preauth && 1344 pmonitor != NULL && pmonitor->m_pid > 1) { 1345 debug("Killing privsep child %d", pmonitor->m_pid); 1346 if (kill(pmonitor->m_pid, SIGKILL) != 0 && 1347 errno != ESRCH) { 1348 error_f("kill(%d): %s", pmonitor->m_pid, 1349 strerror(errno)); 1350 } 1351 } 1352 } 1353 /* Override default fatal exit value when auth was attempted */ 1354 if (i == 255 && auth_attempted) 1355 _exit(EXIT_AUTH_ATTEMPTED); 1356 _exit(i); 1357} 1358