Annotation of src/usr.bin/ssh/sshd.c, Revision 1.565
1.565 ! dtucker 1: /* $OpenBSD: sshd.c,v 1.564 2020/10/18 11:32:02 djm Exp $ */
1.86 markus 2: /*
1.65 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
1.126 deraadt 6: * This program is the ssh daemon. It listens for connections from clients,
7: * and performs authentication, executes use commands or shell, and forwards
1.65 deraadt 8: * information to/from the application to the user client over an encrypted
1.126 deraadt 9: * connection. This can also handle forwarding of X11, TCP/IP, and
10: * authentication agent connections.
1.98 markus 11: *
1.126 deraadt 12: * As far as I am concerned, the code I have written for this software
13: * can be used freely for any purpose. Any derived versions of this
14: * software must be clearly marked as such, and if the derived work is
15: * incompatible with the protocol description in the RFC file, it must be
16: * called by a name other than "ssh" or "Secure Shell".
17: *
18: * SSH2 implementation:
1.231 provos 19: * Privilege Separation:
1.126 deraadt 20: *
1.231 provos 21: * Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved.
22: * Copyright (c) 2002 Niels Provos. All rights reserved.
1.126 deraadt 23: *
24: * Redistribution and use in source and binary forms, with or without
25: * modification, are permitted provided that the following conditions
26: * are met:
27: * 1. Redistributions of source code must retain the above copyright
28: * notice, this list of conditions and the following disclaimer.
29: * 2. Redistributions in binary form must reproduce the above copyright
30: * notice, this list of conditions and the following disclaimer in the
31: * documentation and/or other materials provided with the distribution.
32: *
33: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
34: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
35: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
36: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
37: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
38: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
39: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
40: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
41: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
42: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.65 deraadt 43: */
1.1 deraadt 44:
1.343 deraadt 45: #include <sys/types.h>
1.320 stevesk 46: #include <sys/ioctl.h>
1.321 stevesk 47: #include <sys/wait.h>
1.343 deraadt 48: #include <sys/tree.h>
1.323 stevesk 49: #include <sys/stat.h>
1.334 stevesk 50: #include <sys/socket.h>
1.340 stevesk 51: #include <sys/time.h>
1.357 djm 52: #include <sys/queue.h>
1.319 stevesk 53:
1.336 stevesk 54: #include <errno.h>
1.335 stevesk 55: #include <fcntl.h>
1.338 stevesk 56: #include <netdb.h>
1.319 stevesk 57: #include <paths.h>
1.333 stevesk 58: #include <pwd.h>
1.322 stevesk 59: #include <signal.h>
1.342 stevesk 60: #include <stdio.h>
1.341 stevesk 61: #include <stdlib.h>
1.339 stevesk 62: #include <string.h>
1.541 naddy 63: #include <stdarg.h>
1.344 dtucker 64: #include <unistd.h>
1.438 deraadt 65: #include <limits.h>
1.1 deraadt 66:
1.426 markus 67: #ifdef WITH_OPENSSL
1.155 markus 68: #include <openssl/bn.h>
1.426 markus 69: #endif
1.155 markus 70:
1.343 deraadt 71: #include "xmalloc.h"
1.155 markus 72: #include "ssh.h"
73: #include "ssh2.h"
1.171 djm 74: #include "sshpty.h"
1.1 deraadt 75: #include "packet.h"
1.155 markus 76: #include "log.h"
1.511 markus 77: #include "sshbuf.h"
1.428 millert 78: #include "misc.h"
1.454 markus 79: #include "match.h"
1.1 deraadt 80: #include "servconf.h"
81: #include "uidswap.h"
1.33 markus 82: #include "compat.h"
1.155 markus 83: #include "cipher.h"
1.415 markus 84: #include "digest.h"
1.512 markus 85: #include "sshkey.h"
1.98 markus 86: #include "kex.h"
87: #include "myproposal.h"
1.108 markus 88: #include "authfile.h"
1.154 markus 89: #include "pathnames.h"
1.155 markus 90: #include "atomicio.h"
91: #include "canohost.h"
1.343 deraadt 92: #include "hostfile.h"
1.155 markus 93: #include "auth.h"
1.404 markus 94: #include "authfd.h"
1.294 djm 95: #include "msg.h"
1.186 markus 96: #include "dispatch.h"
1.206 stevesk 97: #include "channels.h"
1.230 provos 98: #include "session.h"
1.231 provos 99: #include "monitor.h"
1.343 deraadt 100: #ifdef GSSAPI
101: #include "ssh-gss.h"
102: #endif
1.231 provos 103: #include "monitor_wrap.h"
1.385 djm 104: #include "ssh-sandbox.h"
1.506 djm 105: #include "auth-options.h"
1.332 stevesk 106: #include "version.h"
1.432 djm 107: #include "ssherr.h"
1.542 djm 108: #include "sk-api.h"
1.522 djm 109:
1.296 djm 110: /* Re-exec fds */
111: #define REEXEC_DEVCRYPTO_RESERVED_FD (STDERR_FILENO + 1)
112: #define REEXEC_STARTUP_PIPE_FD (STDERR_FILENO + 2)
113: #define REEXEC_CONFIG_PASS_FD (STDERR_FILENO + 3)
114: #define REEXEC_MIN_FREE_FD (STDERR_FILENO + 4)
115:
1.138 markus 116: extern char *__progname;
117:
1.1 deraadt 118: /* Server configuration options. */
119: ServerOptions options;
120:
121: /* Name of the server configuration file. */
1.154 markus 122: char *config_file_name = _PATH_SERVER_CONFIG_FILE;
1.1 deraadt 123:
1.105 markus 124: /*
1.65 deraadt 125: * Debug mode flag. This can be set on the command line. If debug
126: * mode is enabled, extra debugging output will be sent to the system
127: * log, the daemon will not go to background, and will exit after processing
128: * the first connection.
129: */
1.1 deraadt 130: int debug_flag = 0;
131:
1.499 djm 132: /*
133: * Indicating that the daemon should only test the configuration and keys.
134: * If test_flag > 1 ("-T" flag), then sshd will also dump the effective
135: * configuration, optionally using connection information provided by the
136: * "-C" flag.
137: */
1.521 djm 138: static int test_flag = 0;
1.203 stevesk 139:
1.1 deraadt 140: /* Flag indicating that the daemon is being started from inetd. */
1.521 djm 141: static int inetd_flag = 0;
1.1 deraadt 142:
1.135 markus 143: /* Flag indicating that sshd should not detach and become a daemon. */
1.521 djm 144: static int no_daemon_flag = 0;
1.135 markus 145:
1.47 markus 146: /* debug goes to stderr unless inetd_flag is set */
1.521 djm 147: static int log_stderr = 0;
1.47 markus 148:
1.1 deraadt 149: /* Saved arguments to main(). */
1.521 djm 150: static char **saved_argv;
1.1 deraadt 151:
1.294 djm 152: /* re-exec */
1.521 djm 153: static int rexeced_flag = 0;
154: static int rexec_flag = 1;
155: static int rexec_argc = 0;
156: static char **rexec_argv;
1.294 djm 157:
1.66 markus 158: /*
1.75 markus 159: * The sockets that the server is listening; this is used in the SIGHUP
160: * signal handler.
1.66 markus 161: */
1.75 markus 162: #define MAX_LISTEN_SOCKS 16
1.521 djm 163: static int listen_socks[MAX_LISTEN_SOCKS];
164: static int num_listen_socks = 0;
1.1 deraadt 165:
1.404 markus 166: /* Daemon's agent connection */
1.432 djm 167: int auth_sock = -1;
1.521 djm 168: static int have_agent = 0;
1.404 markus 169:
1.66 markus 170: /*
171: * Any really sensitive data in the application is contained in this
172: * structure. The idea is that this structure could be locked into memory so
173: * that the pages do not get written into swap. However, there are some
174: * problems. The private key contains BIGNUMs, and we do not (in principle)
175: * have access to the internals of them, and locking just the structure is
176: * not very useful. Currently, memory locking is not implemented.
177: */
1.64 markus 178: struct {
1.488 markus 179: struct sshkey **host_keys; /* all private host keys */
180: struct sshkey **host_pubkeys; /* all public host keys */
181: struct sshkey **host_certificates; /* all public host certificates */
182: int have_ssh2_key;
1.1 deraadt 183: } sensitive_data;
184:
1.199 markus 185: /* This is set to true when a signal is received. */
1.212 markus 186: static volatile sig_atomic_t received_sighup = 0;
187: static volatile sig_atomic_t received_sigterm = 0;
1.1 deraadt 188:
1.96 markus 189: /* session identifier, used by RSA-auth */
1.140 markus 190: u_char session_id[16];
1.96 markus 191:
1.108 markus 192: /* same for ssh2 */
1.140 markus 193: u_char *session_id2 = NULL;
1.269 markus 194: u_int session_id2_len = 0;
1.108 markus 195:
1.125 markus 196: /* record remote hostname or ip */
1.438 deraadt 197: u_int utmp_len = HOST_NAME_MAX+1;
1.125 markus 198:
1.533 djm 199: /*
200: * startup_pipes/flags are used for tracking children of the listening sshd
201: * process early in their lifespans. This tracking is needed for three things:
202: *
203: * 1) Implementing the MaxStartups limit of concurrent unauthenticated
204: * connections.
205: * 2) Avoiding a race condition for SIGHUP processing, where child processes
206: * may have listen_socks open that could collide with main listener process
207: * after it restarts.
208: * 3) Ensuring that rexec'd sshd processes have received their initial state
209: * from the parent listen process before handling SIGHUP.
210: *
211: * Child processes signal that they have completed closure of the listen_socks
212: * and (if applicable) received their rexec state by sending a char over their
213: * sock. Child processes signal that authentication has completed by closing
214: * the sock (or by exiting).
215: */
1.521 djm 216: static int *startup_pipes = NULL;
1.533 djm 217: static int *startup_flags = NULL; /* Indicates child closed listener */
218: static int startup_pipe = -1; /* in child */
1.211 markus 219:
1.231 provos 220: /* variables used for privilege separation */
1.337 dtucker 221: int use_privsep = -1;
1.285 dtucker 222: struct monitor *pmonitor = NULL;
1.386 djm 223: int privsep_is_preauth = 1;
1.231 provos 224:
1.527 djm 225: /* global connection state and authentication contexts */
1.278 markus 226: Authctxt *the_authctxt = NULL;
1.527 djm 227: struct ssh *the_active_state;
1.278 markus 228:
1.506 djm 229: /* global key/cert auth options. XXX move to permanent ssh->authctxt? */
230: struct sshauthopt *auth_opts = NULL;
231:
1.337 dtucker 232: /* sshd_config buffer */
1.511 markus 233: struct sshbuf *cfg;
1.337 dtucker 234:
1.546 djm 235: /* Included files from the configuration file */
236: struct include_list includes = TAILQ_HEAD_INITIALIZER(includes);
237:
1.299 dtucker 238: /* message to be displayed after login */
1.510 markus 239: struct sshbuf *loginmsg;
1.299 dtucker 240:
1.1 deraadt 241: /* Prototypes for various functions defined later in this file. */
1.200 itojun 242: void destroy_sensitive_data(void);
1.231 provos 243: void demote_sensitive_data(void);
1.525 djm 244: static void do_ssh2_kex(struct ssh *);
1.129 provos 245:
1.545 djm 246: static char *listener_proctitle;
247:
1.87 markus 248: /*
1.75 markus 249: * Close all listening sockets
250: */
1.200 itojun 251: static void
1.75 markus 252: close_listen_socks(void)
253: {
254: int i;
1.250 deraadt 255:
1.75 markus 256: for (i = 0; i < num_listen_socks; i++)
257: close(listen_socks[i]);
258: num_listen_socks = -1;
259: }
260:
1.211 markus 261: static void
262: close_startup_pipes(void)
263: {
264: int i;
1.250 deraadt 265:
1.211 markus 266: if (startup_pipes)
267: for (i = 0; i < options.max_startups; i++)
268: if (startup_pipes[i] != -1)
269: close(startup_pipes[i]);
270: }
271:
1.75 markus 272: /*
1.65 deraadt 273: * Signal handler for SIGHUP. Sshd execs itself when it receives SIGHUP;
274: * the effect is to reread the configuration file (and to regenerate
275: * the server key).
276: */
1.327 deraadt 277:
278: /*ARGSUSED*/
1.200 itojun 279: static void
1.64 markus 280: sighup_handler(int sig)
1.1 deraadt 281: {
1.64 markus 282: received_sighup = 1;
1.1 deraadt 283: }
284:
1.65 deraadt 285: /*
286: * Called from the main program after receiving SIGHUP.
287: * Restarts the server.
288: */
1.200 itojun 289: static void
1.165 itojun 290: sighup_restart(void)
1.1 deraadt 291: {
1.264 itojun 292: logit("Received SIGHUP; restarting.");
1.479 dtucker 293: if (options.pid_file != NULL)
294: unlink(options.pid_file);
1.75 markus 295: close_listen_socks();
1.211 markus 296: close_startup_pipes();
1.544 dtucker 297: ssh_signal(SIGHUP, SIG_IGN); /* will be restored after exec */
1.64 markus 298: execv(saved_argv[0], saved_argv);
1.264 itojun 299: logit("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0],
1.250 deraadt 300: strerror(errno));
1.64 markus 301: exit(1);
1.1 deraadt 302: }
303:
1.65 deraadt 304: /*
305: * Generic signal handler for terminating signals in the master daemon.
306: */
1.327 deraadt 307: /*ARGSUSED*/
1.200 itojun 308: static void
1.64 markus 309: sigterm_handler(int sig)
1.1 deraadt 310: {
1.199 markus 311: received_sigterm = sig;
1.1 deraadt 312: }
313:
1.65 deraadt 314: /*
315: * SIGCHLD handler. This is called whenever a child dies. This will then
1.199 markus 316: * reap any zombies left by exited children.
1.65 deraadt 317: */
1.327 deraadt 318: /*ARGSUSED*/
1.200 itojun 319: static void
1.64 markus 320: main_sigchld_handler(int sig)
1.1 deraadt 321: {
1.250 deraadt 322: int save_errno = errno;
1.239 markus 323: pid_t pid;
1.64 markus 324: int status;
1.60 deraadt 325:
1.544 dtucker 326: debug("main_sigchld_handler: %s", strsignal(sig));
327:
1.239 markus 328: while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
1.537 deraadt 329: (pid == -1 && errno == EINTR))
1.64 markus 330: ;
331: errno = save_errno;
1.1 deraadt 332: }
333:
1.65 deraadt 334: /*
335: * Signal handler for the alarm after the login grace period has expired.
336: */
1.327 deraadt 337: /*ARGSUSED*/
1.200 itojun 338: static void
1.64 markus 339: grace_alarm_handler(int sig)
1.1 deraadt 340: {
1.285 dtucker 341: if (use_privsep && pmonitor != NULL && pmonitor->m_pid > 0)
342: kill(pmonitor->m_pid, SIGALRM);
1.394 djm 343:
344: /*
345: * Try to kill any processes that we have spawned, E.g. authorized
346: * keys command helpers.
347: */
348: if (getpgid(0) == getpid()) {
1.544 dtucker 349: ssh_signal(SIGTERM, SIG_IGN);
1.416 djm 350: kill(0, SIGTERM);
1.394 djm 351: }
1.285 dtucker 352:
1.527 djm 353: /* XXX pre-format ipaddr/port so we don't need to access active_state */
1.64 markus 354: /* Log error and exit. */
1.466 djm 355: sigdie("Timeout before authentication for %s port %d",
1.527 djm 356: ssh_remote_ipaddr(the_active_state),
357: ssh_remote_port(the_active_state));
1.62 markus 358: }
359:
1.134 markus 360: /* Destroy the host and server keys. They will no longer be needed. */
1.108 markus 361: void
362: destroy_sensitive_data(void)
363: {
1.493 djm 364: u_int i;
1.134 markus 365:
1.217 deraadt 366: for (i = 0; i < options.num_host_key_files; i++) {
1.134 markus 367: if (sensitive_data.host_keys[i]) {
1.512 markus 368: sshkey_free(sensitive_data.host_keys[i]);
1.134 markus 369: sensitive_data.host_keys[i] = NULL;
370: }
1.373 djm 371: if (sensitive_data.host_certificates[i]) {
1.512 markus 372: sshkey_free(sensitive_data.host_certificates[i]);
1.373 djm 373: sensitive_data.host_certificates[i] = NULL;
374: }
1.134 markus 375: }
376: }
377:
1.231 provos 378: /* Demote private to public keys for network child */
379: void
380: demote_sensitive_data(void)
381: {
1.488 markus 382: struct sshkey *tmp;
1.493 djm 383: u_int i;
1.512 markus 384: int r;
1.231 provos 385:
386: for (i = 0; i < options.num_host_key_files; i++) {
387: if (sensitive_data.host_keys[i]) {
1.515 djm 388: if ((r = sshkey_from_private(
389: sensitive_data.host_keys[i], &tmp)) != 0)
1.564 djm 390: fatal_r(r, "could not demote host %s key",
391: sshkey_type(sensitive_data.host_keys[i]));
1.512 markus 392: sshkey_free(sensitive_data.host_keys[i]);
1.231 provos 393: sensitive_data.host_keys[i] = tmp;
394: }
1.373 djm 395: /* Certs do not need demotion */
1.231 provos 396: }
397: }
398:
1.233 markus 399: static void
1.231 provos 400: privsep_preauth_child(void)
401: {
1.253 deraadt 402: gid_t gidset[1];
1.250 deraadt 403: struct passwd *pw;
1.231 provos 404:
405: /* Enable challenge-response authentication for privilege separation */
406: privsep_challenge_enable();
1.419 djm 407:
1.420 markus 408: #ifdef GSSAPI
1.419 djm 409: /* Cache supported mechanism OIDs for later use */
1.516 djm 410: ssh_gssapi_prepare_supported_oids();
1.420 markus 411: #endif
1.231 provos 412:
413: /* Demote the private keys to public keys. */
414: demote_sensitive_data();
415:
1.460 djm 416: /* Demote the child */
417: if (getuid() == 0 || geteuid() == 0) {
418: if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL)
419: fatal("Privilege separation user %s does not exist",
420: SSH_PRIVSEP_USER);
1.500 djm 421: pw = pwcopy(pw); /* Ensure mutable */
1.460 djm 422: endpwent();
1.500 djm 423: freezero(pw->pw_passwd, strlen(pw->pw_passwd));
1.460 djm 424:
425: /* Change our root directory */
426: if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1)
427: fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR,
428: strerror(errno));
429: if (chdir("/") == -1)
430: fatal("chdir(\"/\"): %s", strerror(errno));
431:
432: /*
433: * Drop our privileges
434: * NB. Can't use setusercontext() after chroot.
435: */
436: debug3("privsep user:group %u:%u", (u_int)pw->pw_uid,
437: (u_int)pw->pw_gid);
438: gidset[0] = pw->pw_gid;
1.537 deraadt 439: if (setgroups(1, gidset) == -1)
1.460 djm 440: fatal("setgroups: %.100s", strerror(errno));
441: permanently_set_uid(pw);
442: }
1.231 provos 443: }
444:
1.278 markus 445: static int
1.525 djm 446: privsep_preauth(struct ssh *ssh)
1.237 markus 447: {
1.432 djm 448: int status, r;
1.237 markus 449: pid_t pid;
1.384 djm 450: struct ssh_sandbox *box = NULL;
1.237 markus 451:
452: /* Set up unprivileged child process to deal with network data */
1.242 mouring 453: pmonitor = monitor_init();
1.237 markus 454: /* Store a pointer to the kex for later rekeying */
1.525 djm 455: pmonitor->m_pkex = &ssh->kex;
1.237 markus 456:
1.393 djm 457: if (use_privsep == PRIVSEP_ON)
1.384 djm 458: box = ssh_sandbox_init();
1.237 markus 459: pid = fork();
460: if (pid == -1) {
461: fatal("fork of unprivileged child failed");
462: } else if (pid != 0) {
1.245 mpech 463: debug2("Network child is on pid %ld", (long)pid);
1.237 markus 464:
1.392 markus 465: pmonitor->m_pid = pid;
1.432 djm 466: if (have_agent) {
467: r = ssh_get_authentication_socket(&auth_sock);
468: if (r != 0) {
1.564 djm 469: error_r(r, "Could not get agent socket");
1.432 djm 470: have_agent = 0;
471: }
472: }
1.384 djm 473: if (box != NULL)
474: ssh_sandbox_parent_preauth(box, pid);
1.526 djm 475: monitor_child_preauth(ssh, pmonitor);
1.237 markus 476:
477: /* Wait for the child's exit status */
1.537 deraadt 478: while (waitpid(pid, &status, 0) == -1) {
1.386 djm 479: if (errno == EINTR)
480: continue;
481: pmonitor->m_pid = -1;
1.564 djm 482: fatal_f("waitpid: %s", strerror(errno));
1.384 djm 483: }
1.386 djm 484: privsep_is_preauth = 0;
485: pmonitor->m_pid = -1;
1.384 djm 486: if (WIFEXITED(status)) {
487: if (WEXITSTATUS(status) != 0)
1.564 djm 488: fatal_f("preauth child exited with status %d",
489: WEXITSTATUS(status));
1.384 djm 490: } else if (WIFSIGNALED(status))
1.564 djm 491: fatal_f("preauth child terminated by signal %d",
492: WTERMSIG(status));
1.384 djm 493: if (box != NULL)
494: ssh_sandbox_parent_finish(box);
495: return 1;
1.237 markus 496: } else {
497: /* child */
1.383 djm 498: close(pmonitor->m_sendfd);
499: close(pmonitor->m_log_recvfd);
1.237 markus 500:
1.383 djm 501: /* Arrange for logging to be sent to the monitor */
502: set_log_handler(mm_log_handler, pmonitor);
1.237 markus 503:
1.460 djm 504: privsep_preauth_child();
1.238 stevesk 505: setproctitle("%s", "[net]");
1.384 djm 506: if (box != NULL)
507: ssh_sandbox_child(box);
508:
509: return 0;
1.237 markus 510: }
511: }
512:
1.233 markus 513: static void
1.525 djm 514: privsep_postauth(struct ssh *ssh, Authctxt *authctxt)
1.231 provos 515: {
1.474 djm 516: if (authctxt->pw->pw_uid == 0) {
1.231 provos 517: /* File descriptor passing is broken or root login */
518: use_privsep = 0;
1.315 djm 519: goto skip;
1.231 provos 520: }
1.234 markus 521:
1.231 provos 522: /* New socket pair */
1.242 mouring 523: monitor_reinit(pmonitor);
1.231 provos 524:
1.242 mouring 525: pmonitor->m_pid = fork();
526: if (pmonitor->m_pid == -1)
1.231 provos 527: fatal("fork of unprivileged child failed");
1.242 mouring 528: else if (pmonitor->m_pid != 0) {
1.364 markus 529: verbose("User child is on pid %ld", (long)pmonitor->m_pid);
1.510 markus 530: sshbuf_reset(loginmsg);
1.526 djm 531: monitor_clear_keystate(ssh, pmonitor);
532: monitor_child_postauth(ssh, pmonitor);
1.231 provos 533:
534: /* NEVERREACHED */
535: exit(0);
536: }
537:
1.383 djm 538: /* child */
539:
1.242 mouring 540: close(pmonitor->m_sendfd);
1.383 djm 541: pmonitor->m_sendfd = -1;
1.231 provos 542:
543: /* Demote the private keys to public keys. */
544: demote_sensitive_data();
1.354 djm 545:
1.231 provos 546: /* Drop privileges */
547: do_setusercontext(authctxt->pw);
548:
1.315 djm 549: skip:
1.231 provos 550: /* It is safe now to apply the key state */
1.526 djm 551: monitor_apply_keystate(ssh, pmonitor);
1.312 markus 552:
553: /*
554: * Tell the packet layer that authentication was successful, since
555: * this information is not part of the key state.
556: */
1.525 djm 557: ssh_packet_set_authenticated(ssh);
1.231 provos 558: }
559:
1.509 djm 560: static void
561: append_hostkey_type(struct sshbuf *b, const char *s)
562: {
563: int r;
564:
565: if (match_pattern_list(s, options.hostkeyalgorithms, 0) != 1) {
1.564 djm 566: debug3_f("%s key not permitted by HostkeyAlgorithms", s);
1.509 djm 567: return;
568: }
569: if ((r = sshbuf_putf(b, "%s%s", sshbuf_len(b) > 0 ? "," : "", s)) != 0)
1.564 djm 570: fatal_fr(r, "sshbuf_putf");
1.509 djm 571: }
572:
1.200 itojun 573: static char *
1.134 markus 574: list_hostkey_types(void)
575: {
1.509 djm 576: struct sshbuf *b;
577: struct sshkey *key;
1.281 jakob 578: char *ret;
1.493 djm 579: u_int i;
1.223 markus 580:
1.509 djm 581: if ((b = sshbuf_new()) == NULL)
1.564 djm 582: fatal_f("sshbuf_new failed");
1.217 deraadt 583: for (i = 0; i < options.num_host_key_files; i++) {
1.373 djm 584: key = sensitive_data.host_keys[i];
1.443 djm 585: if (key == NULL)
1.404 markus 586: key = sensitive_data.host_pubkeys[i];
1.472 markus 587: if (key == NULL)
1.134 markus 588: continue;
1.214 deraadt 589: switch (key->type) {
1.134 markus 590: case KEY_RSA:
1.509 djm 591: /* for RSA we also support SHA2 signatures */
592: append_hostkey_type(b, "rsa-sha2-512");
593: append_hostkey_type(b, "rsa-sha2-256");
594: /* FALLTHROUGH */
1.134 markus 595: case KEY_DSA:
1.378 djm 596: case KEY_ECDSA:
1.412 markus 597: case KEY_ED25519:
1.542 djm 598: case KEY_ECDSA_SK:
599: case KEY_ED25519_SK:
1.505 markus 600: case KEY_XMSS:
1.509 djm 601: append_hostkey_type(b, sshkey_ssh_name(key));
1.134 markus 602: break;
603: }
1.373 djm 604: /* If the private key has a cert peer, then list that too */
605: key = sensitive_data.host_certificates[i];
606: if (key == NULL)
607: continue;
608: switch (key->type) {
609: case KEY_RSA_CERT:
1.509 djm 610: /* for RSA we also support SHA2 signatures */
611: append_hostkey_type(b,
612: "rsa-sha2-512-cert-v01@openssh.com");
613: append_hostkey_type(b,
614: "rsa-sha2-256-cert-v01@openssh.com");
615: /* FALLTHROUGH */
1.373 djm 616: case KEY_DSA_CERT:
1.378 djm 617: case KEY_ECDSA_CERT:
1.412 markus 618: case KEY_ED25519_CERT:
1.542 djm 619: case KEY_ECDSA_SK_CERT:
620: case KEY_ED25519_SK_CERT:
1.505 markus 621: case KEY_XMSS_CERT:
1.509 djm 622: append_hostkey_type(b, sshkey_ssh_name(key));
1.373 djm 623: break;
624: }
1.134 markus 625: }
1.509 djm 626: if ((ret = sshbuf_dup_string(b)) == NULL)
1.564 djm 627: fatal_f("sshbuf_dup_string failed");
1.509 djm 628: sshbuf_free(b);
1.564 djm 629: debug_f("%s", ret);
1.281 jakob 630: return ret;
1.134 markus 631: }
632:
1.488 markus 633: static struct sshkey *
1.440 djm 634: get_hostkey_by_type(int type, int nid, int need_private, struct ssh *ssh)
1.134 markus 635: {
1.493 djm 636: u_int i;
1.488 markus 637: struct sshkey *key;
1.250 deraadt 638:
1.217 deraadt 639: for (i = 0; i < options.num_host_key_files; i++) {
1.375 djm 640: switch (type) {
641: case KEY_RSA_CERT:
642: case KEY_DSA_CERT:
1.378 djm 643: case KEY_ECDSA_CERT:
1.412 markus 644: case KEY_ED25519_CERT:
1.542 djm 645: case KEY_ECDSA_SK_CERT:
646: case KEY_ED25519_SK_CERT:
1.505 markus 647: case KEY_XMSS_CERT:
1.373 djm 648: key = sensitive_data.host_certificates[i];
1.375 djm 649: break;
650: default:
1.373 djm 651: key = sensitive_data.host_keys[i];
1.404 markus 652: if (key == NULL && !need_private)
653: key = sensitive_data.host_pubkeys[i];
1.375 djm 654: break;
655: }
1.542 djm 656: if (key == NULL || key->type != type)
657: continue;
658: switch (type) {
659: case KEY_ECDSA:
660: case KEY_ECDSA_SK:
661: case KEY_ECDSA_CERT:
662: case KEY_ECDSA_SK_CERT:
663: if (key->ecdsa_nid != nid)
664: continue;
665: /* FALLTHROUGH */
666: default:
1.373 djm 667: return need_private ?
668: sensitive_data.host_keys[i] : key;
1.542 djm 669: }
1.134 markus 670: }
671: return NULL;
1.96 markus 672: }
673:
1.488 markus 674: struct sshkey *
1.440 djm 675: get_hostkey_public_by_type(int type, int nid, struct ssh *ssh)
1.373 djm 676: {
1.440 djm 677: return get_hostkey_by_type(type, nid, 0, ssh);
1.373 djm 678: }
679:
1.488 markus 680: struct sshkey *
1.440 djm 681: get_hostkey_private_by_type(int type, int nid, struct ssh *ssh)
1.373 djm 682: {
1.440 djm 683: return get_hostkey_by_type(type, nid, 1, ssh);
1.373 djm 684: }
685:
1.488 markus 686: struct sshkey *
1.231 provos 687: get_hostkey_by_index(int ind)
688: {
1.493 djm 689: if (ind < 0 || (u_int)ind >= options.num_host_key_files)
1.231 provos 690: return (NULL);
691: return (sensitive_data.host_keys[ind]);
692: }
693:
1.488 markus 694: struct sshkey *
1.435 markus 695: get_hostkey_public_by_index(int ind, struct ssh *ssh)
1.404 markus 696: {
1.493 djm 697: if (ind < 0 || (u_int)ind >= options.num_host_key_files)
1.404 markus 698: return (NULL);
699: return (sensitive_data.host_pubkeys[ind]);
700: }
701:
1.231 provos 702: int
1.488 markus 703: get_hostkey_index(struct sshkey *key, int compare, struct ssh *ssh)
1.231 provos 704: {
1.493 djm 705: u_int i;
1.250 deraadt 706:
1.231 provos 707: for (i = 0; i < options.num_host_key_files; i++) {
1.512 markus 708: if (sshkey_is_cert(key)) {
1.442 djm 709: if (key == sensitive_data.host_certificates[i] ||
710: (compare && sensitive_data.host_certificates[i] &&
711: sshkey_equal(key,
712: sensitive_data.host_certificates[i])))
1.373 djm 713: return (i);
714: } else {
1.442 djm 715: if (key == sensitive_data.host_keys[i] ||
716: (compare && sensitive_data.host_keys[i] &&
717: sshkey_equal(key, sensitive_data.host_keys[i])))
1.373 djm 718: return (i);
1.442 djm 719: if (key == sensitive_data.host_pubkeys[i] ||
720: (compare && sensitive_data.host_pubkeys[i] &&
721: sshkey_equal(key, sensitive_data.host_pubkeys[i])))
1.404 markus 722: return (i);
1.373 djm 723: }
1.231 provos 724: }
725: return (-1);
726: }
727:
1.439 djm 728: /* Inform the client of all hostkeys */
729: static void
730: notify_hostkeys(struct ssh *ssh)
731: {
732: struct sshbuf *buf;
733: struct sshkey *key;
1.493 djm 734: u_int i, nkeys;
735: int r;
1.439 djm 736: char *fp;
1.446 dtucker 737:
738: /* Some clients cannot cope with the hostkeys message, skip those. */
1.527 djm 739: if (ssh->compat & SSH_BUG_HOSTKEYS)
1.446 dtucker 740: return;
1.439 djm 741:
742: if ((buf = sshbuf_new()) == NULL)
1.564 djm 743: fatal_f("sshbuf_new");
1.439 djm 744: for (i = nkeys = 0; i < options.num_host_key_files; i++) {
745: key = get_hostkey_public_by_index(i, ssh);
746: if (key == NULL || key->type == KEY_UNSPEC ||
1.472 markus 747: sshkey_is_cert(key))
1.439 djm 748: continue;
749: fp = sshkey_fingerprint(key, options.fingerprint_hash,
750: SSH_FP_DEFAULT);
1.564 djm 751: debug3_f("key %d: %s %s", i, sshkey_ssh_name(key), fp);
1.439 djm 752: free(fp);
1.442 djm 753: if (nkeys == 0) {
1.525 djm 754: /*
755: * Start building the request when we find the
756: * first usable key.
757: */
758: if ((r = sshpkt_start(ssh, SSH2_MSG_GLOBAL_REQUEST)) != 0 ||
759: (r = sshpkt_put_cstring(ssh, "hostkeys-00@openssh.com")) != 0 ||
760: (r = sshpkt_put_u8(ssh, 0)) != 0) /* want reply */
761: sshpkt_fatal(ssh, r, "%s: start request", __func__);
1.442 djm 762: }
1.525 djm 763: /* Append the key to the request */
1.442 djm 764: sshbuf_reset(buf);
765: if ((r = sshkey_putb(key, buf)) != 0)
1.564 djm 766: fatal_fr(r, "couldn't put hostkey %d", i);
1.525 djm 767: if ((r = sshpkt_put_stringb(ssh, buf)) != 0)
768: sshpkt_fatal(ssh, r, "%s: append key", __func__);
1.439 djm 769: nkeys++;
770: }
1.564 djm 771: debug3_f("sent %u hostkeys", nkeys);
1.439 djm 772: if (nkeys == 0)
1.564 djm 773: fatal_f("no hostkeys");
1.525 djm 774: if ((r = sshpkt_send(ssh)) != 0)
775: sshpkt_fatal(ssh, r, "%s: send", __func__);
1.442 djm 776: sshbuf_free(buf);
1.439 djm 777: }
778:
1.124 markus 779: /*
780: * returns 1 if connection should be dropped, 0 otherwise.
781: * dropping starts at connection #max_startups_begin with a probability
782: * of (max_startups_rate/100). the probability increases linearly until
783: * all connections are dropped for startups > max_startups
784: */
1.200 itojun 785: static int
1.555 djm 786: should_drop_connection(int startups)
1.124 markus 787: {
1.303 mickey 788: int p, r;
1.124 markus 789:
790: if (startups < options.max_startups_begin)
791: return 0;
792: if (startups >= options.max_startups)
793: return 1;
794: if (options.max_startups_rate == 100)
795: return 1;
796:
797: p = 100 - options.max_startups_rate;
798: p *= startups - options.max_startups_begin;
1.303 mickey 799: p /= options.max_startups - options.max_startups_begin;
1.124 markus 800: p += options.max_startups_rate;
1.356 djm 801: r = arc4random_uniform(100);
1.124 markus 802:
1.564 djm 803: debug_f("p %d, r %d", p, r);
1.124 markus 804: return (r < p) ? 1 : 0;
805: }
806:
1.555 djm 807: /*
808: * Check whether connection should be accepted by MaxStartups.
809: * Returns 0 if the connection is accepted. If the connection is refused,
810: * returns 1 and attempts to send notification to client.
811: * Logs when the MaxStartups condition is entered or exited, and periodically
812: * while in that state.
813: */
814: static int
815: drop_connection(int sock, int startups)
816: {
817: char *laddr, *raddr;
818: const char msg[] = "Exceeded MaxStartups\r\n";
819: static time_t last_drop, first_drop;
820: static u_int ndropped;
821: LogLevel drop_level = SYSLOG_LEVEL_VERBOSE;
822: time_t now;
823:
824: now = monotime();
825: if (!should_drop_connection(startups)) {
826: if (last_drop != 0 &&
827: startups < options.max_startups_begin - 1) {
828: /* XXX maybe need better hysteresis here */
829: logit("exited MaxStartups throttling after %s, "
830: "%u connections dropped",
831: fmt_timeframe(now - first_drop), ndropped);
832: last_drop = 0;
833: }
834: return 0;
835: }
836:
837: #define SSHD_MAXSTARTUPS_LOG_INTERVAL (5 * 60)
838: if (last_drop == 0) {
839: error("beginning MaxStartups throttling");
840: drop_level = SYSLOG_LEVEL_INFO;
841: first_drop = now;
842: ndropped = 0;
843: } else if (last_drop + SSHD_MAXSTARTUPS_LOG_INTERVAL < now) {
844: /* Periodic logs */
845: error("in MaxStartups throttling for %s, "
846: "%u connections dropped",
847: fmt_timeframe(now - first_drop), ndropped + 1);
848: drop_level = SYSLOG_LEVEL_INFO;
849: }
850: last_drop = now;
851: ndropped++;
852:
853: laddr = get_local_ipaddr(sock);
854: raddr = get_peer_ipaddr(sock);
855: do_log2(drop_level, "drop connection #%d from [%s]:%d on [%s]:%d "
856: "past MaxStartups", startups, raddr, get_peer_port(sock),
857: laddr, get_local_port(sock));
858: free(laddr);
859: free(raddr);
860: /* best-effort notification to client */
861: (void)write(sock, msg, sizeof(msg) - 1);
862: return 1;
863: }
864:
1.215 markus 865: static void
866: usage(void)
867: {
1.565 ! dtucker 868: fprintf(stderr, "%s, %s\n", SSH_VERSION, SSH_OPENSSL_VERSION);
1.289 markus 869: fprintf(stderr,
1.473 naddy 870: "usage: sshd [-46DdeiqTt] [-C connection_spec] [-c host_cert_file]\n"
1.399 dtucker 871: " [-E log_file] [-f config_file] [-g login_grace_time]\n"
1.473 naddy 872: " [-h host_key_file] [-o option] [-p port] [-u len]\n"
1.289 markus 873: );
1.215 markus 874: exit(1);
875: }
876:
1.294 djm 877: static void
1.467 djm 878: send_rexec_state(int fd, struct sshbuf *conf)
1.294 djm 879: {
1.546 djm 880: struct sshbuf *m = NULL, *inc = NULL;
881: struct include_item *item = NULL;
1.467 djm 882: int r;
1.294 djm 883:
1.564 djm 884: debug3_f("entering fd = %d config len %zu", fd,
1.467 djm 885: sshbuf_len(conf));
1.294 djm 886:
1.546 djm 887: if ((m = sshbuf_new()) == NULL || (inc = sshbuf_new()) == NULL)
1.564 djm 888: fatal_f("sshbuf_new failed");
1.546 djm 889:
890: /* pack includes into a string */
891: TAILQ_FOREACH(item, &includes, entry) {
892: if ((r = sshbuf_put_cstring(inc, item->selector)) != 0 ||
893: (r = sshbuf_put_cstring(inc, item->filename)) != 0 ||
1.547 djm 894: (r = sshbuf_put_stringb(inc, item->contents)) != 0)
1.564 djm 895: fatal_fr(r, "compose includes");
1.546 djm 896: }
897:
1.294 djm 898: /*
899: * Protocol from reexec master to child:
900: * string configuration
1.546 djm 901: * string included_files[] {
902: * string selector
903: * string filename
904: * string contents
905: * }
1.294 djm 906: */
1.546 djm 907: if ((r = sshbuf_put_stringb(m, conf)) != 0 ||
908: (r = sshbuf_put_stringb(m, inc)) != 0)
1.564 djm 909: fatal_fr(r, "compose config");
1.467 djm 910: if (ssh_msg_send(fd, 0, m) == -1)
1.564 djm 911: error_f("ssh_msg_send failed");
1.294 djm 912:
1.467 djm 913: sshbuf_free(m);
1.546 djm 914: sshbuf_free(inc);
1.294 djm 915:
1.564 djm 916: debug3_f("done");
1.294 djm 917: }
918:
919: static void
1.511 markus 920: recv_rexec_state(int fd, struct sshbuf *conf)
1.294 djm 921: {
1.546 djm 922: struct sshbuf *m, *inc;
1.511 markus 923: u_char *cp, ver;
924: size_t len;
925: int r;
1.546 djm 926: struct include_item *item;
1.294 djm 927:
1.564 djm 928: debug3_f("entering fd = %d", fd);
1.294 djm 929:
1.546 djm 930: if ((m = sshbuf_new()) == NULL || (inc = sshbuf_new()) == NULL)
1.564 djm 931: fatal_f("sshbuf_new failed");
1.511 markus 932: if (ssh_msg_recv(fd, m) == -1)
1.564 djm 933: fatal_f("ssh_msg_recv failed");
1.511 markus 934: if ((r = sshbuf_get_u8(m, &ver)) != 0)
1.564 djm 935: fatal_fr(r, "parse version");
1.511 markus 936: if (ver != 0)
1.564 djm 937: fatal_f("rexec version mismatch");
1.546 djm 938: if ((r = sshbuf_get_string(m, &cp, &len)) != 0 ||
939: (r = sshbuf_get_stringb(m, inc)) != 0)
1.564 djm 940: fatal_fr(r, "parse config");
1.546 djm 941:
1.511 markus 942: if (conf != NULL && (r = sshbuf_put(conf, cp, len)))
1.564 djm 943: fatal_fr(r, "sshbuf_put");
1.294 djm 944:
1.546 djm 945: while (sshbuf_len(inc) != 0) {
946: item = xcalloc(1, sizeof(*item));
947: if ((item->contents = sshbuf_new()) == NULL)
1.564 djm 948: fatal_f("sshbuf_new failed");
1.546 djm 949: if ((r = sshbuf_get_cstring(inc, &item->selector, NULL)) != 0 ||
950: (r = sshbuf_get_cstring(inc, &item->filename, NULL)) != 0 ||
951: (r = sshbuf_get_stringb(inc, item->contents)) != 0)
1.564 djm 952: fatal_fr(r, "parse includes");
1.546 djm 953: TAILQ_INSERT_TAIL(&includes, item, entry);
954: }
955:
1.402 djm 956: free(cp);
1.511 markus 957: sshbuf_free(m);
1.294 djm 958:
1.564 djm 959: debug3_f("done");
1.294 djm 960: }
961:
1.345 djm 962: /* Accept a connection from inetd */
963: static void
964: server_accept_inetd(int *sock_in, int *sock_out)
965: {
966: if (rexeced_flag) {
967: close(REEXEC_CONFIG_PASS_FD);
968: *sock_in = *sock_out = dup(STDIN_FILENO);
969: } else {
970: *sock_in = dup(STDIN_FILENO);
971: *sock_out = dup(STDOUT_FILENO);
972: }
973: /*
974: * We intentionally do not close the descriptors 0, 1, and 2
975: * as our code for setting the descriptors won't work if
976: * ttyfd happens to be one of those.
977: */
1.562 djm 978: if (stdfd_devnull(1, 1, !log_stderr) == -1)
1.564 djm 979: error_f("stdfd_devnull failed");
1.345 djm 980: debug("inetd sockets after dupping: %d, %d", *sock_in, *sock_out);
981: }
982:
983: /*
984: * Listen for TCP connections
985: */
986: static void
1.494 djm 987: listen_on_addrs(struct listenaddr *la)
1.345 djm 988: {
1.494 djm 989: int ret, listen_sock;
1.345 djm 990: struct addrinfo *ai;
991: char ntop[NI_MAXHOST], strport[NI_MAXSERV];
992:
1.494 djm 993: for (ai = la->addrs; ai; ai = ai->ai_next) {
1.345 djm 994: if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
995: continue;
996: if (num_listen_socks >= MAX_LISTEN_SOCKS)
997: fatal("Too many listen sockets. "
998: "Enlarge MAX_LISTEN_SOCKS");
999: if ((ret = getnameinfo(ai->ai_addr, ai->ai_addrlen,
1000: ntop, sizeof(ntop), strport, sizeof(strport),
1001: NI_NUMERICHOST|NI_NUMERICSERV)) != 0) {
1002: error("getnameinfo failed: %.100s",
1.352 dtucker 1003: ssh_gai_strerror(ret));
1.345 djm 1004: continue;
1005: }
1006: /* Create socket for listening. */
1.370 dtucker 1007: listen_sock = socket(ai->ai_family, ai->ai_socktype,
1008: ai->ai_protocol);
1.537 deraadt 1009: if (listen_sock == -1) {
1.345 djm 1010: /* kernel may not support ipv6 */
1011: verbose("socket: %.100s", strerror(errno));
1012: continue;
1013: }
1014: if (set_nonblock(listen_sock) == -1) {
1.483 djm 1015: close(listen_sock);
1016: continue;
1017: }
1018: if (fcntl(listen_sock, F_SETFD, FD_CLOEXEC) == -1) {
1019: verbose("socket: CLOEXEC: %s", strerror(errno));
1.345 djm 1020: close(listen_sock);
1021: continue;
1022: }
1.494 djm 1023: /* Socket options */
1024: set_reuseaddr(listen_sock);
1025: if (la->rdomain != NULL &&
1026: set_rdomain(listen_sock, la->rdomain) == -1) {
1027: close(listen_sock);
1028: continue;
1029: }
1.345 djm 1030:
1031: debug("Bind to port %s on %s.", strport, ntop);
1032:
1033: /* Bind the socket to the desired port. */
1.537 deraadt 1034: if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) == -1) {
1.345 djm 1035: error("Bind to port %s on %s failed: %.200s.",
1036: strport, ntop, strerror(errno));
1037: close(listen_sock);
1038: continue;
1039: }
1040: listen_socks[num_listen_socks] = listen_sock;
1041: num_listen_socks++;
1042:
1043: /* Start listening on the port. */
1.537 deraadt 1044: if (listen(listen_sock, SSH_LISTEN_BACKLOG) == -1)
1.345 djm 1045: fatal("listen on [%s]:%s: %.100s",
1046: ntop, strport, strerror(errno));
1.494 djm 1047: logit("Server listening on %s port %s%s%s.",
1048: ntop, strport,
1049: la->rdomain == NULL ? "" : " rdomain ",
1050: la->rdomain == NULL ? "" : la->rdomain);
1.345 djm 1051: }
1.494 djm 1052: }
1053:
1054: static void
1055: server_listen(void)
1056: {
1057: u_int i;
1058:
1059: for (i = 0; i < options.num_listen_addrs; i++) {
1060: listen_on_addrs(&options.listen_addrs[i]);
1061: freeaddrinfo(options.listen_addrs[i].addrs);
1062: free(options.listen_addrs[i].rdomain);
1063: memset(&options.listen_addrs[i], 0,
1064: sizeof(options.listen_addrs[i]));
1065: }
1066: free(options.listen_addrs);
1067: options.listen_addrs = NULL;
1068: options.num_listen_addrs = 0;
1.345 djm 1069:
1070: if (!num_listen_socks)
1071: fatal("Cannot bind any address.");
1072: }
1073:
1074: /*
1075: * The main TCP accept loop. Note that, for the non-debug case, returns
1076: * from this function are in a forked subprocess.
1077: */
1078: static void
1079: server_accept_loop(int *sock_in, int *sock_out, int *newsock, int *config_s)
1080: {
1081: fd_set *fdset;
1082: int i, j, ret, maxfd;
1.543 djm 1083: int ostartups = -1, startups = 0, listening = 0, lameduck = 0;
1.345 djm 1084: int startup_p[2] = { -1 , -1 };
1.533 djm 1085: char c = 0;
1.345 djm 1086: struct sockaddr_storage from;
1087: socklen_t fromlen;
1088: pid_t pid;
1089:
1090: /* setup fd set for accept */
1091: fdset = NULL;
1092: maxfd = 0;
1093: for (i = 0; i < num_listen_socks; i++)
1094: if (listen_socks[i] > maxfd)
1095: maxfd = listen_socks[i];
1.550 djm 1096: /* pipes connected to unauthenticated child sshd processes */
1.345 djm 1097: startup_pipes = xcalloc(options.max_startups, sizeof(int));
1.533 djm 1098: startup_flags = xcalloc(options.max_startups, sizeof(int));
1.345 djm 1099: for (i = 0; i < options.max_startups; i++)
1100: startup_pipes[i] = -1;
1101:
1102: /*
1103: * Stay listening for connections until the system crashes or
1104: * the daemon is killed with a signal.
1105: */
1106: for (;;) {
1.543 djm 1107: if (ostartups != startups) {
1.545 djm 1108: setproctitle("%s [listener] %d of %d-%d startups",
1109: listener_proctitle, startups,
1110: options.max_startups_begin, options.max_startups);
1.543 djm 1111: ostartups = startups;
1112: }
1.533 djm 1113: if (received_sighup) {
1114: if (!lameduck) {
1115: debug("Received SIGHUP; waiting for children");
1116: close_listen_socks();
1117: lameduck = 1;
1118: }
1119: if (listening <= 0)
1120: sighup_restart();
1121: }
1.462 mmcc 1122: free(fdset);
1.458 deraadt 1123: fdset = xcalloc(howmany(maxfd + 1, NFDBITS),
1.345 djm 1124: sizeof(fd_mask));
1125:
1126: for (i = 0; i < num_listen_socks; i++)
1127: FD_SET(listen_socks[i], fdset);
1128: for (i = 0; i < options.max_startups; i++)
1129: if (startup_pipes[i] != -1)
1130: FD_SET(startup_pipes[i], fdset);
1131:
1132: /* Wait in select until there is a connection. */
1133: ret = select(maxfd+1, fdset, NULL, NULL, NULL);
1.537 deraadt 1134: if (ret == -1 && errno != EINTR)
1.345 djm 1135: error("select: %.100s", strerror(errno));
1136: if (received_sigterm) {
1137: logit("Received signal %d; terminating.",
1138: (int) received_sigterm);
1139: close_listen_socks();
1.430 djm 1140: if (options.pid_file != NULL)
1141: unlink(options.pid_file);
1.382 djm 1142: exit(received_sigterm == SIGTERM ? 0 : 255);
1.345 djm 1143: }
1.537 deraadt 1144: if (ret == -1)
1.345 djm 1145: continue;
1146:
1.533 djm 1147: for (i = 0; i < options.max_startups; i++) {
1148: if (startup_pipes[i] == -1 ||
1149: !FD_ISSET(startup_pipes[i], fdset))
1150: continue;
1151: switch (read(startup_pipes[i], &c, sizeof(c))) {
1152: case -1:
1153: if (errno == EINTR || errno == EAGAIN)
1154: continue;
1155: if (errno != EPIPE) {
1.564 djm 1156: error_f("startup pipe %d (fd=%d): "
1157: "read %s", i, startup_pipes[i],
1158: strerror(errno));
1.533 djm 1159: }
1160: /* FALLTHROUGH */
1161: case 0:
1162: /* child exited or completed auth */
1.345 djm 1163: close(startup_pipes[i]);
1164: startup_pipes[i] = -1;
1165: startups--;
1.533 djm 1166: if (startup_flags[i])
1167: listening--;
1168: break;
1169: case 1:
1170: /* child has finished preliminaries */
1171: if (startup_flags[i]) {
1172: listening--;
1173: startup_flags[i] = 0;
1174: }
1175: break;
1.345 djm 1176: }
1.533 djm 1177: }
1.345 djm 1178: for (i = 0; i < num_listen_socks; i++) {
1179: if (!FD_ISSET(listen_socks[i], fdset))
1180: continue;
1181: fromlen = sizeof(from);
1182: *newsock = accept(listen_socks[i],
1183: (struct sockaddr *)&from, &fromlen);
1.537 deraadt 1184: if (*newsock == -1) {
1.398 markus 1185: if (errno != EINTR && errno != EWOULDBLOCK &&
1186: errno != ECONNABORTED)
1.389 djm 1187: error("accept: %.100s",
1188: strerror(errno));
1189: if (errno == EMFILE || errno == ENFILE)
1190: usleep(100 * 1000);
1.345 djm 1191: continue;
1192: }
1.555 djm 1193: if (unset_nonblock(*newsock) == -1 ||
1194: drop_connection(*newsock, startups) ||
1195: pipe(startup_p) == -1) {
1.345 djm 1196: close(*newsock);
1197: continue;
1198: }
1199:
1200: if (rexec_flag && socketpair(AF_UNIX,
1201: SOCK_STREAM, 0, config_s) == -1) {
1202: error("reexec socketpair: %s",
1203: strerror(errno));
1204: close(*newsock);
1205: close(startup_p[0]);
1206: close(startup_p[1]);
1207: continue;
1208: }
1209:
1210: for (j = 0; j < options.max_startups; j++)
1211: if (startup_pipes[j] == -1) {
1212: startup_pipes[j] = startup_p[0];
1213: if (maxfd < startup_p[0])
1214: maxfd = startup_p[0];
1215: startups++;
1.533 djm 1216: startup_flags[j] = 1;
1.345 djm 1217: break;
1218: }
1219:
1220: /*
1221: * Got connection. Fork a child to handle it, unless
1222: * we are in debugging mode.
1223: */
1224: if (debug_flag) {
1225: /*
1226: * In debugging mode. Close the listening
1227: * socket, and start processing the
1228: * connection without forking.
1229: */
1230: debug("Server will not fork when running in debugging mode.");
1231: close_listen_socks();
1232: *sock_in = *newsock;
1233: *sock_out = *newsock;
1234: close(startup_p[0]);
1235: close(startup_p[1]);
1236: startup_pipe = -1;
1237: pid = getpid();
1238: if (rexec_flag) {
1.511 markus 1239: send_rexec_state(config_s[0], cfg);
1.345 djm 1240: close(config_s[0]);
1241: }
1.533 djm 1242: return;
1.345 djm 1243: }
1244:
1245: /*
1246: * Normal production daemon. Fork, and have
1247: * the child process the connection. The
1248: * parent continues listening.
1249: */
1.533 djm 1250: listening++;
1.345 djm 1251: if ((pid = fork()) == 0) {
1252: /*
1253: * Child. Close the listening and
1254: * max_startup sockets. Start using
1255: * the accepted socket. Reinitialize
1256: * logging (since our pid has changed).
1.533 djm 1257: * We return from this function to handle
1.345 djm 1258: * the connection.
1259: */
1260: startup_pipe = startup_p[1];
1261: close_startup_pipes();
1262: close_listen_socks();
1263: *sock_in = *newsock;
1264: *sock_out = *newsock;
1265: log_init(__progname,
1266: options.log_level,
1267: options.log_facility,
1268: log_stderr);
1269: if (rexec_flag)
1270: close(config_s[0]);
1.533 djm 1271: else {
1272: /*
1273: * Signal parent that the preliminaries
1274: * for this child are complete. For the
1275: * re-exec case, this happens after the
1276: * child has received the rexec state
1277: * from the server.
1278: */
1279: (void)atomicio(vwrite, startup_pipe,
1280: "\0", 1);
1281: }
1282: return;
1.345 djm 1283: }
1284:
1285: /* Parent. Stay in the loop. */
1.537 deraadt 1286: if (pid == -1)
1.345 djm 1287: error("fork: %.100s", strerror(errno));
1288: else
1289: debug("Forked child %ld.", (long)pid);
1290:
1291: close(startup_p[1]);
1292:
1293: if (rexec_flag) {
1.554 markus 1294: close(config_s[1]);
1.511 markus 1295: send_rexec_state(config_s[0], cfg);
1.345 djm 1296: close(config_s[0]);
1297: }
1298: close(*newsock);
1299: }
1300: }
1301: }
1302:
1.466 djm 1303: /*
1304: * If IP options are supported, make sure there are none (log and
1305: * return an error if any are found). Basically we are worried about
1306: * source routing; it can be used to pretend you are somebody
1307: * (ip-address) you are not. That itself may be "almost acceptable"
1.507 djm 1308: * under certain circumstances, but rhosts authentication is useless
1.466 djm 1309: * if source routing is accepted. Notice also that if we just dropped
1310: * source routing here, the other side could use IP spoofing to do
1311: * rest of the interaction and could still bypass security. So we
1312: * exit here if we detect any IP options.
1313: */
1314: static void
1315: check_ip_options(struct ssh *ssh)
1316: {
1317: int sock_in = ssh_packet_get_connection_in(ssh);
1318: struct sockaddr_storage from;
1319: u_char opts[200];
1.475 djm 1320: socklen_t i, option_size = sizeof(opts), fromlen = sizeof(from);
1.466 djm 1321: char text[sizeof(opts) * 3 + 1];
1322:
1323: memset(&from, 0, sizeof(from));
1324: if (getpeername(sock_in, (struct sockaddr *)&from,
1.537 deraadt 1325: &fromlen) == -1)
1.466 djm 1326: return;
1327: if (from.ss_family != AF_INET)
1328: return;
1329: /* XXX IPv6 options? */
1330:
1331: if (getsockopt(sock_in, IPPROTO_IP, IP_OPTIONS, opts,
1332: &option_size) >= 0 && option_size != 0) {
1333: text[0] = '\0';
1334: for (i = 0; i < option_size; i++)
1335: snprintf(text + i*3, sizeof(text) - i*3,
1336: " %2.2x", opts[i]);
1337: fatal("Connection from %.100s port %d with IP opts: %.800s",
1338: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh), text);
1339: }
1340: return;
1341: }
1.345 djm 1342:
1.495 djm 1343: /* Set the routing domain for this process */
1344: static void
1345: set_process_rdomain(struct ssh *ssh, const char *name)
1346: {
1347: int rtable, ortable = getrtable();
1348: const char *errstr;
1349:
1350: if (name == NULL)
1351: return; /* default */
1352:
1353: if (strcmp(name, "%D") == 0) {
1354: /* "expands" to routing domain of connection */
1355: if ((name = ssh_packet_rdomain_in(ssh)) == NULL)
1356: return;
1357: }
1358:
1359: rtable = (int)strtonum(name, 0, 255, &errstr);
1360: if (errstr != NULL) /* Shouldn't happen */
1361: fatal("Invalid routing domain \"%s\": %s", name, errstr);
1362: if (rtable != ortable && setrtable(rtable) != 0)
1363: fatal("Unable to set routing domain %d: %s",
1364: rtable, strerror(errno));
1.564 djm 1365: debug_f("set routing domain %d (was %d)", rtable, ortable);
1.495 djm 1366: }
1367:
1.508 dtucker 1368: static void
1369: accumulate_host_timing_secret(struct sshbuf *server_cfg,
1.536 djm 1370: struct sshkey *key)
1.508 dtucker 1371: {
1372: static struct ssh_digest_ctx *ctx;
1373: u_char *hash;
1374: size_t len;
1375: struct sshbuf *buf;
1376: int r;
1377:
1378: if (ctx == NULL && (ctx = ssh_digest_start(SSH_DIGEST_SHA512)) == NULL)
1.564 djm 1379: fatal_f("ssh_digest_start");
1.508 dtucker 1380: if (key == NULL) { /* finalize */
1381: /* add server config in case we are using agent for host keys */
1382: if (ssh_digest_update(ctx, sshbuf_ptr(server_cfg),
1383: sshbuf_len(server_cfg)) != 0)
1.564 djm 1384: fatal_f("ssh_digest_update");
1.508 dtucker 1385: len = ssh_digest_bytes(SSH_DIGEST_SHA512);
1386: hash = xmalloc(len);
1387: if (ssh_digest_final(ctx, hash, len) != 0)
1.564 djm 1388: fatal_f("ssh_digest_final");
1.508 dtucker 1389: options.timing_secret = PEEK_U64(hash);
1390: freezero(hash, len);
1391: ssh_digest_free(ctx);
1392: ctx = NULL;
1393: return;
1394: }
1395: if ((buf = sshbuf_new()) == NULL)
1.564 djm 1396: fatal_f("could not allocate buffer");
1.508 dtucker 1397: if ((r = sshkey_private_serialize(key, buf)) != 0)
1.564 djm 1398: fatal_fr(r, "decode key");
1.508 dtucker 1399: if (ssh_digest_update(ctx, sshbuf_ptr(buf), sshbuf_len(buf)) != 0)
1.564 djm 1400: fatal_f("ssh_digest_update");
1.508 dtucker 1401: sshbuf_reset(buf);
1402: sshbuf_free(buf);
1403: }
1404:
1.545 djm 1405: static char *
1406: prepare_proctitle(int ac, char **av)
1407: {
1408: char *ret = NULL;
1409: int i;
1410:
1411: for (i = 0; i < ac; i++)
1412: xextendf(&ret, " ", "%s", av[i]);
1413: return ret;
1414: }
1415:
1.65 deraadt 1416: /*
1417: * Main program for the daemon.
1418: */
1.2 provos 1419: int
1420: main(int ac, char **av)
1.1 deraadt 1421: {
1.466 djm 1422: struct ssh *ssh = NULL;
1.64 markus 1423: extern char *optarg;
1424: extern int optind;
1.493 djm 1425: int r, opt, on = 1, already_daemon, remote_port;
1.297 avsm 1426: int sock_in = -1, sock_out = -1, newsock = -1;
1.496 djm 1427: const char *remote_ip, *rdomain;
1.447 dtucker 1428: char *fp, *line, *laddr, *logfile = NULL;
1.345 djm 1429: int config_s[2] = { -1 , -1 };
1.493 djm 1430: u_int i, j;
1.364 markus 1431: u_int64_t ibytes, obytes;
1.362 dtucker 1432: mode_t new_umask;
1.488 markus 1433: struct sshkey *key;
1434: struct sshkey *pubkey;
1.404 markus 1435: int keytype;
1.230 provos 1436: Authctxt *authctxt;
1.498 dtucker 1437: struct connection_info *connection_info = NULL;
1.64 markus 1438:
1.138 markus 1439: /* Save argv. */
1.64 markus 1440: saved_argv = av;
1.294 djm 1441: rexec_argc = ac;
1.313 djm 1442:
1443: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1444: sanitise_stdfd();
1.64 markus 1445:
1446: /* Initialize configuration options to their default values. */
1447: initialize_server_options(&options);
1448:
1449: /* Parse command-line arguments. */
1.450 djm 1450: while ((opt = getopt(ac, av,
1451: "C:E:b:c:f:g:h:k:o:p:u:46DQRTdeiqrt")) != -1) {
1.64 markus 1452: switch (opt) {
1.75 markus 1453: case '4':
1.305 djm 1454: options.address_family = AF_INET;
1.75 markus 1455: break;
1456: case '6':
1.305 djm 1457: options.address_family = AF_INET6;
1.75 markus 1458: break;
1.64 markus 1459: case 'f':
1460: config_file_name = optarg;
1461: break;
1.373 djm 1462: case 'c':
1.493 djm 1463: servconf_add_hostcert("[command-line]", 0,
1464: &options, optarg);
1.373 djm 1465: break;
1.64 markus 1466: case 'd':
1.273 markus 1467: if (debug_flag == 0) {
1.127 markus 1468: debug_flag = 1;
1469: options.log_level = SYSLOG_LEVEL_DEBUG1;
1.273 markus 1470: } else if (options.log_level < SYSLOG_LEVEL_DEBUG3)
1.127 markus 1471: options.log_level++;
1.64 markus 1472: break;
1.135 markus 1473: case 'D':
1474: no_daemon_flag = 1;
1.192 lebel 1475: break;
1.399 dtucker 1476: case 'E':
1.459 dtucker 1477: logfile = optarg;
1.399 dtucker 1478: /* FALLTHROUGH */
1.192 lebel 1479: case 'e':
1480: log_stderr = 1;
1.135 markus 1481: break;
1.64 markus 1482: case 'i':
1483: inetd_flag = 1;
1484: break;
1.294 djm 1485: case 'r':
1486: rexec_flag = 0;
1487: break;
1488: case 'R':
1489: rexeced_flag = 1;
1490: inetd_flag = 1;
1491: break;
1.64 markus 1492: case 'Q':
1.158 markus 1493: /* ignored */
1.64 markus 1494: break;
1495: case 'q':
1496: options.log_level = SYSLOG_LEVEL_QUIET;
1497: break;
1498: case 'b':
1.473 naddy 1499: /* protocol 1, ignored */
1.64 markus 1500: break;
1501: case 'p':
1.75 markus 1502: options.ports_from_cmdline = 1;
1.127 markus 1503: if (options.num_ports >= MAX_PORTS) {
1504: fprintf(stderr, "too many ports.\n");
1505: exit(1);
1506: }
1.193 stevesk 1507: options.ports[options.num_ports++] = a2port(optarg);
1.366 djm 1508: if (options.ports[options.num_ports-1] <= 0) {
1.193 stevesk 1509: fprintf(stderr, "Bad port number.\n");
1510: exit(1);
1511: }
1.64 markus 1512: break;
1513: case 'g':
1.197 stevesk 1514: if ((options.login_grace_time = convtime(optarg)) == -1) {
1515: fprintf(stderr, "Invalid login grace time.\n");
1516: exit(1);
1517: }
1.64 markus 1518: break;
1519: case 'k':
1.473 naddy 1520: /* protocol 1, ignored */
1.64 markus 1521: break;
1522: case 'h':
1.493 djm 1523: servconf_add_hostkey("[command-line]", 0,
1.519 djm 1524: &options, optarg, 1);
1.64 markus 1525: break;
1.203 stevesk 1526: case 't':
1527: test_flag = 1;
1528: break;
1.358 dtucker 1529: case 'T':
1530: test_flag = 2;
1531: break;
1532: case 'C':
1.523 djm 1533: connection_info = get_connection_info(ssh, 0, 0);
1.391 dtucker 1534: if (parse_server_match_testspec(connection_info,
1535: optarg) == -1)
1536: exit(1);
1.358 dtucker 1537: break;
1.125 markus 1538: case 'u':
1.438 deraadt 1539: utmp_len = (u_int)strtonum(optarg, 0, HOST_NAME_MAX+1+1, NULL);
1540: if (utmp_len > HOST_NAME_MAX+1) {
1.257 stevesk 1541: fprintf(stderr, "Invalid utmp length.\n");
1542: exit(1);
1543: }
1.125 markus 1544: break;
1.215 markus 1545: case 'o':
1.283 markus 1546: line = xstrdup(optarg);
1547: if (process_server_config_line(&options, line,
1.546 djm 1548: "command-line", 0, NULL, NULL, &includes) != 0)
1.217 deraadt 1549: exit(1);
1.402 djm 1550: free(line);
1.215 markus 1551: break;
1.64 markus 1552: case '?':
1553: default:
1.215 markus 1554: usage();
1555: break;
1.64 markus 1556: }
1557: }
1.294 djm 1558: if (rexeced_flag || inetd_flag)
1559: rexec_flag = 0;
1.518 djm 1560: if (!test_flag && rexec_flag && !path_absolute(av[0]))
1.294 djm 1561: fatal("sshd re-exec requires execution with an absolute path");
1562: if (rexeced_flag)
1.296 djm 1563: closefrom(REEXEC_MIN_FREE_FD);
1564: else
1565: closefrom(REEXEC_DEVCRYPTO_RESERVED_FD);
1.294 djm 1566:
1.426 markus 1567: #ifdef WITH_OPENSSL
1.379 djm 1568: OpenSSL_add_all_algorithms();
1.426 markus 1569: #endif
1.64 markus 1570:
1.399 dtucker 1571: /* If requested, redirect the logs to the specified logfile. */
1.459 dtucker 1572: if (logfile != NULL)
1.399 dtucker 1573: log_redirect_stderr_to(logfile);
1.75 markus 1574: /*
1575: * Force logging to stderr until we have loaded the private host
1576: * key (unless started from inetd)
1577: */
1.138 markus 1578: log_init(__progname,
1.224 markus 1579: options.log_level == SYSLOG_LEVEL_NOT_SET ?
1580: SYSLOG_LEVEL_INFO : options.log_level,
1581: options.log_facility == SYSLOG_FACILITY_NOT_SET ?
1582: SYSLOG_FACILITY_AUTH : options.log_facility,
1.548 djm 1583: log_stderr || !inetd_flag || debug_flag);
1.75 markus 1584:
1.294 djm 1585: sensitive_data.have_ssh2_key = 0;
1586:
1.358 dtucker 1587: /*
1.498 dtucker 1588: * If we're not doing an extended test do not silently ignore connection
1589: * test params.
1.358 dtucker 1590: */
1.498 dtucker 1591: if (test_flag < 2 && connection_info != NULL)
1.358 dtucker 1592: fatal("Config test connection parameter (-C) provided without "
1593: "test mode (-T)");
1594:
1.294 djm 1595: /* Fetch our configuration */
1.511 markus 1596: if ((cfg = sshbuf_new()) == NULL)
1.564 djm 1597: fatal_f("sshbuf_new failed");
1.533 djm 1598: if (rexeced_flag) {
1.560 markus 1599: setproctitle("%s", "[rexeced]");
1.511 markus 1600: recv_rexec_state(REEXEC_CONFIG_PASS_FD, cfg);
1.533 djm 1601: if (!debug_flag) {
1602: startup_pipe = dup(REEXEC_STARTUP_PIPE_FD);
1603: close(REEXEC_STARTUP_PIPE_FD);
1604: /*
1605: * Signal parent that this child is at a point where
1606: * they can go away if they have a SIGHUP pending.
1607: */
1608: (void)atomicio(vwrite, startup_pipe, "\0", 1);
1609: }
1.549 djm 1610: } else if (strcasecmp(config_file_name, "none") != 0)
1.511 markus 1611: load_server_config(config_file_name, cfg);
1.294 djm 1612:
1.337 dtucker 1613: parse_server_config(&options, rexeced_flag ? "rexec" : config_file_name,
1.546 djm 1614: cfg, &includes, NULL);
1.64 markus 1615:
1616: /* Fill in default values for those options not explicitly set. */
1617: fill_default_server_options(&options);
1.350 dtucker 1618:
1619: /* challenge-response is implemented via keyboard interactive */
1620: if (options.challenge_response_authentication)
1621: options.kbd_interactive_authentication = 1;
1.395 djm 1622:
1623: /* Check that options are sensible */
1624: if (options.authorized_keys_command_user == NULL &&
1625: (options.authorized_keys_command != NULL &&
1626: strcasecmp(options.authorized_keys_command, "none") != 0))
1627: fatal("AuthorizedKeysCommand set without "
1628: "AuthorizedKeysCommandUser");
1.449 djm 1629: if (options.authorized_principals_command_user == NULL &&
1630: (options.authorized_principals_command != NULL &&
1631: strcasecmp(options.authorized_principals_command, "none") != 0))
1632: fatal("AuthorizedPrincipalsCommand set without "
1633: "AuthorizedPrincipalsCommandUser");
1.396 djm 1634:
1635: /*
1636: * Check whether there is any path through configured auth methods.
1637: * Unfortunately it is not possible to verify this generally before
1638: * daemonisation in the presence of Match block, but this catches
1639: * and warns for trivial misconfigurations that could break login.
1640: */
1641: if (options.num_auth_methods != 0) {
1.493 djm 1642: for (i = 0; i < options.num_auth_methods; i++) {
1643: if (auth2_methods_valid(options.auth_methods[i],
1.396 djm 1644: 1) == 0)
1645: break;
1646: }
1.493 djm 1647: if (i >= options.num_auth_methods)
1.396 djm 1648: fatal("AuthenticationMethods cannot be satisfied by "
1649: "enabled authentication methods");
1650: }
1.305 djm 1651:
1.64 markus 1652: /* Check that there are no remaining arguments. */
1653: if (optind < ac) {
1654: fprintf(stderr, "Extra argument %s.\n", av[optind]);
1655: exit(1);
1656: }
1657:
1.565 ! dtucker 1658: debug("sshd version %s, %s", SSH_VERSION, SSH_OPENSSL_VERSION);
1.64 markus 1659:
1.404 markus 1660: /* load host keys */
1.329 djm 1661: sensitive_data.host_keys = xcalloc(options.num_host_key_files,
1.488 markus 1662: sizeof(struct sshkey *));
1.404 markus 1663: sensitive_data.host_pubkeys = xcalloc(options.num_host_key_files,
1.488 markus 1664: sizeof(struct sshkey *));
1.404 markus 1665:
1666: if (options.host_key_agent) {
1667: if (strcmp(options.host_key_agent, SSH_AUTHSOCKET_ENV_NAME))
1668: setenv(SSH_AUTHSOCKET_ENV_NAME,
1669: options.host_key_agent, 1);
1.433 djm 1670: if ((r = ssh_get_authentication_socket(NULL)) == 0)
1671: have_agent = 1;
1672: else
1.564 djm 1673: error_r(r, "Could not connect to agent \"%s\"",
1674: options.host_key_agent);
1.404 markus 1675: }
1.134 markus 1676:
1.217 deraadt 1677: for (i = 0; i < options.num_host_key_files; i++) {
1.519 djm 1678: int ll = options.host_key_file_userprovided[i] ?
1679: SYSLOG_LEVEL_ERROR : SYSLOG_LEVEL_DEBUG1;
1680:
1.430 djm 1681: if (options.host_key_files[i] == NULL)
1682: continue;
1.512 markus 1683: if ((r = sshkey_load_private(options.host_key_files[i], "",
1684: &key, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
1.564 djm 1685: do_log2_r(r, ll, "Unable to load host key \"%s\"",
1686: options.host_key_files[i]);
1.542 djm 1687: if (sshkey_is_sk(key) &&
1688: key->sk_flags & SSH_SK_USER_PRESENCE_REQD) {
1689: debug("host key %s requires user presence, ignoring",
1690: options.host_key_files[i]);
1691: key->sk_flags &= ~SSH_SK_USER_PRESENCE_REQD;
1692: }
1693: if (r == 0 && key != NULL &&
1694: (r = sshkey_shield_private(key)) != 0) {
1.564 djm 1695: do_log2_r(r, ll, "Unable to shield host key \"%s\"",
1696: options.host_key_files[i]);
1.536 djm 1697: sshkey_free(key);
1698: key = NULL;
1699: }
1.512 markus 1700: if ((r = sshkey_load_public(options.host_key_files[i],
1701: &pubkey, NULL)) != 0 && r != SSH_ERR_SYSTEM_ERROR)
1.564 djm 1702: do_log2_r(r, ll, "Unable to load host key \"%s\"",
1703: options.host_key_files[i]);
1.557 djm 1704: if (pubkey != NULL && key != NULL) {
1705: if (!sshkey_equal(pubkey, key)) {
1706: error("Public key for %s does not match "
1707: "private key", options.host_key_files[i]);
1708: sshkey_free(pubkey);
1709: pubkey = NULL;
1710: }
1711: }
1712: if (pubkey == NULL && key != NULL) {
1.515 djm 1713: if ((r = sshkey_from_private(key, &pubkey)) != 0)
1.564 djm 1714: fatal_r(r, "Could not demote key: \"%s\"",
1715: options.host_key_files[i]);
1.557 djm 1716: }
1.179 markus 1717: sensitive_data.host_keys[i] = key;
1.404 markus 1718: sensitive_data.host_pubkeys[i] = pubkey;
1719:
1.472 markus 1720: if (key == NULL && pubkey != NULL && have_agent) {
1.443 djm 1721: debug("will rely on agent for hostkey %s",
1722: options.host_key_files[i]);
1.404 markus 1723: keytype = pubkey->type;
1724: } else if (key != NULL) {
1725: keytype = key->type;
1.511 markus 1726: accumulate_host_timing_secret(cfg, key);
1.404 markus 1727: } else {
1.519 djm 1728: do_log2(ll, "Unable to load host key: %s",
1.195 markus 1729: options.host_key_files[i]);
1.179 markus 1730: sensitive_data.host_keys[i] = NULL;
1.404 markus 1731: sensitive_data.host_pubkeys[i] = NULL;
1.134 markus 1732: continue;
1733: }
1.404 markus 1734:
1735: switch (keytype) {
1.134 markus 1736: case KEY_RSA:
1737: case KEY_DSA:
1.378 djm 1738: case KEY_ECDSA:
1.412 markus 1739: case KEY_ED25519:
1.542 djm 1740: case KEY_ECDSA_SK:
1741: case KEY_ED25519_SK:
1.505 markus 1742: case KEY_XMSS:
1.441 djm 1743: if (have_agent || key != NULL)
1744: sensitive_data.have_ssh2_key = 1;
1.134 markus 1745: break;
1746: }
1.441 djm 1747: if ((fp = sshkey_fingerprint(pubkey, options.fingerprint_hash,
1748: SSH_FP_DEFAULT)) == NULL)
1749: fatal("sshkey_fingerprint failed");
1750: debug("%s host key #%d: %s %s",
1.472 markus 1751: key ? "private" : "agent", i, sshkey_ssh_name(pubkey), fp);
1.441 djm 1752: free(fp);
1.134 markus 1753: }
1.511 markus 1754: accumulate_host_timing_secret(cfg, NULL);
1.472 markus 1755: if (!sensitive_data.have_ssh2_key) {
1.264 itojun 1756: logit("sshd: no hostkeys available -- exiting.");
1.64 markus 1757: exit(1);
1758: }
1759:
1.373 djm 1760: /*
1761: * Load certificates. They are stored in an array at identical
1762: * indices to the public keys that they relate to.
1763: */
1764: sensitive_data.host_certificates = xcalloc(options.num_host_key_files,
1.488 markus 1765: sizeof(struct sshkey *));
1.373 djm 1766: for (i = 0; i < options.num_host_key_files; i++)
1767: sensitive_data.host_certificates[i] = NULL;
1768:
1769: for (i = 0; i < options.num_host_cert_files; i++) {
1.430 djm 1770: if (options.host_cert_files[i] == NULL)
1771: continue;
1.512 markus 1772: if ((r = sshkey_load_public(options.host_cert_files[i],
1773: &key, NULL)) != 0) {
1.564 djm 1774: error_r(r, "Could not load host certificate \"%s\"",
1775: options.host_cert_files[i]);
1.373 djm 1776: continue;
1777: }
1.512 markus 1778: if (!sshkey_is_cert(key)) {
1.373 djm 1779: error("Certificate file is not a certificate: %s",
1780: options.host_cert_files[i]);
1.512 markus 1781: sshkey_free(key);
1.373 djm 1782: continue;
1783: }
1784: /* Find matching private key */
1785: for (j = 0; j < options.num_host_key_files; j++) {
1.512 markus 1786: if (sshkey_equal_public(key,
1.373 djm 1787: sensitive_data.host_keys[j])) {
1788: sensitive_data.host_certificates[j] = key;
1789: break;
1790: }
1791: }
1792: if (j >= options.num_host_key_files) {
1793: error("No matching private key for certificate: %s",
1794: options.host_cert_files[i]);
1.512 markus 1795: sshkey_free(key);
1.373 djm 1796: continue;
1797: }
1798: sensitive_data.host_certificates[j] = key;
1.493 djm 1799: debug("host certificate: #%u type %d %s", j, key->type,
1.512 markus 1800: sshkey_type(key));
1.373 djm 1801: }
1.426 markus 1802:
1.244 markus 1803: if (use_privsep) {
1804: struct stat st;
1805:
1.327 deraadt 1806: if (getpwnam(SSH_PRIVSEP_USER) == NULL)
1.244 markus 1807: fatal("Privilege separation user %s does not exist",
1808: SSH_PRIVSEP_USER);
1.500 djm 1809: endpwent();
1.244 markus 1810: if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) ||
1811: (S_ISDIR(st.st_mode) == 0))
1812: fatal("Missing privilege separation directory: %s",
1.247 stevesk 1813: _PATH_PRIVSEP_CHROOT_DIR);
1814: if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)
1.262 markus 1815: fatal("%s must be owned by root and not group or "
1816: "world-writable.", _PATH_PRIVSEP_CHROOT_DIR);
1.358 dtucker 1817: }
1818:
1819: if (test_flag > 1) {
1.499 djm 1820: /*
1821: * If no connection info was provided by -C then use
1822: * use a blank one that will cause no predicate to match.
1823: */
1824: if (connection_info == NULL)
1.523 djm 1825: connection_info = get_connection_info(ssh, 0, 0);
1.534 dtucker 1826: connection_info->test = 1;
1.546 djm 1827: parse_server_match_config(&options, &includes, connection_info);
1.358 dtucker 1828: dump_config(&options);
1.108 markus 1829: }
1.203 stevesk 1830:
1831: /* Configuration looks good, so exit if in test mode. */
1832: if (test_flag)
1833: exit(0);
1.108 markus 1834:
1.294 djm 1835: if (rexec_flag) {
1.493 djm 1836: if (rexec_argc < 0)
1837: fatal("rexec_argc %d < 0", rexec_argc);
1.329 djm 1838: rexec_argv = xcalloc(rexec_argc + 2, sizeof(char *));
1.493 djm 1839: for (i = 0; i < (u_int)rexec_argc; i++) {
1.294 djm 1840: debug("rexec_argv[%d]='%s'", i, saved_argv[i]);
1841: rexec_argv[i] = saved_argv[i];
1842: }
1843: rexec_argv[rexec_argc] = "-R";
1844: rexec_argv[rexec_argc + 1] = NULL;
1845: }
1.545 djm 1846: listener_proctitle = prepare_proctitle(ac, av);
1.362 dtucker 1847:
1848: /* Ensure that umask disallows at least group and world write */
1849: new_umask = umask(0077) | 0022;
1850: (void) umask(new_umask);
1.294 djm 1851:
1.108 markus 1852: /* Initialize the log (it is reinitialized below in case we forked). */
1.306 dtucker 1853: if (debug_flag && (!inetd_flag || rexeced_flag))
1.64 markus 1854: log_stderr = 1;
1.563 djm 1855: log_init(__progname, options.log_level,
1856: options.log_facility, log_stderr);
1857: for (i = 0; i < options.num_log_verbose; i++)
1858: log_verbose_add(options.log_verbose[i]);
1.64 markus 1859:
1.108 markus 1860: /*
1.478 dtucker 1861: * If not in debugging mode, not started from inetd and not already
1862: * daemonized (eg re-exec via SIGHUP), disconnect from the controlling
1863: * terminal, and fork. The original process exits.
1.108 markus 1864: */
1.478 dtucker 1865: already_daemon = daemonized();
1866: if (!(debug_flag || inetd_flag || no_daemon_flag || already_daemon)) {
1.345 djm 1867:
1.537 deraadt 1868: if (daemon(0, 0) == -1)
1.64 markus 1869: fatal("daemon() failed: %.200s", strerror(errno));
1870:
1.477 dtucker 1871: disconnect_controlling_tty();
1.64 markus 1872: }
1873: /* Reinitialize the log (because of the fork above). */
1.138 markus 1874: log_init(__progname, options.log_level, options.log_facility, log_stderr);
1.64 markus 1875:
1876: /* Chdir to the root directory so that the current disk can be
1877: unmounted if desired. */
1.401 dtucker 1878: if (chdir("/") == -1)
1879: error("chdir(\"/\"): %s", strerror(errno));
1.217 deraadt 1880:
1.178 markus 1881: /* ignore SIGPIPE */
1.544 dtucker 1882: ssh_signal(SIGPIPE, SIG_IGN);
1.64 markus 1883:
1.345 djm 1884: /* Get a connection, either from inetd or a listening TCP socket */
1.64 markus 1885: if (inetd_flag) {
1.345 djm 1886: server_accept_inetd(&sock_in, &sock_out);
1.64 markus 1887: } else {
1.345 djm 1888: server_listen();
1.75 markus 1889:
1.544 dtucker 1890: ssh_signal(SIGHUP, sighup_handler);
1891: ssh_signal(SIGCHLD, main_sigchld_handler);
1892: ssh_signal(SIGTERM, sigterm_handler);
1893: ssh_signal(SIGQUIT, sigterm_handler);
1.201 markus 1894:
1.345 djm 1895: /*
1896: * Write out the pid file after the sigterm handler
1897: * is setup and the listen sockets are bound
1898: */
1.479 dtucker 1899: if (options.pid_file != NULL && !debug_flag) {
1.345 djm 1900: FILE *f = fopen(options.pid_file, "w");
1.201 markus 1901:
1.270 djm 1902: if (f == NULL) {
1903: error("Couldn't create pid file \"%s\": %s",
1904: options.pid_file, strerror(errno));
1905: } else {
1.245 mpech 1906: fprintf(f, "%ld\n", (long) getpid());
1.64 markus 1907: fclose(f);
1908: }
1909: }
1910:
1.345 djm 1911: /* Accept a connection and return in a forked child */
1912: server_accept_loop(&sock_in, &sock_out,
1913: &newsock, config_s);
1.1 deraadt 1914: }
1915:
1.64 markus 1916: /* This is the child processing a new connection. */
1.288 markus 1917: setproctitle("%s", "[accepted]");
1.294 djm 1918:
1.300 markus 1919: /*
1920: * Create a new session and process group since the 4.4BSD
1921: * setlogin() affects the entire process group. We don't
1922: * want the child to be able to affect the parent.
1923: */
1.537 deraadt 1924: if (!debug_flag && !inetd_flag && setsid() == -1)
1.300 markus 1925: error("setsid: %.100s", strerror(errno));
1926:
1.294 djm 1927: if (rexec_flag) {
1.296 djm 1928: debug("rexec start in %d out %d newsock %d pipe %d sock %d",
1929: sock_in, sock_out, newsock, startup_pipe, config_s[0]);
1.294 djm 1930: dup2(newsock, STDIN_FILENO);
1931: dup2(STDIN_FILENO, STDOUT_FILENO);
1932: if (startup_pipe == -1)
1.296 djm 1933: close(REEXEC_STARTUP_PIPE_FD);
1.407 djm 1934: else if (startup_pipe != REEXEC_STARTUP_PIPE_FD) {
1.296 djm 1935: dup2(startup_pipe, REEXEC_STARTUP_PIPE_FD);
1.407 djm 1936: close(startup_pipe);
1937: startup_pipe = REEXEC_STARTUP_PIPE_FD;
1938: }
1.294 djm 1939:
1.296 djm 1940: dup2(config_s[1], REEXEC_CONFIG_PASS_FD);
1.294 djm 1941: close(config_s[1]);
1.296 djm 1942:
1.559 markus 1943: ssh_signal(SIGHUP, SIG_IGN); /* avoid reset to SIG_DFL */
1.294 djm 1944: execv(rexec_argv[0], rexec_argv);
1945:
1946: /* Reexec has failed, fall back and continue */
1947: error("rexec of %s failed: %s", rexec_argv[0], strerror(errno));
1.296 djm 1948: recv_rexec_state(REEXEC_CONFIG_PASS_FD, NULL);
1.294 djm 1949: log_init(__progname, options.log_level,
1950: options.log_facility, log_stderr);
1951:
1952: /* Clean up fds */
1.296 djm 1953: close(REEXEC_CONFIG_PASS_FD);
1954: newsock = sock_out = sock_in = dup(STDIN_FILENO);
1.562 djm 1955: if (stdfd_devnull(1, 1, 0) == -1)
1.564 djm 1956: error_f("stdfd_devnull failed");
1.296 djm 1957: debug("rexec cleanup in %d out %d newsock %d pipe %d sock %d",
1958: sock_in, sock_out, newsock, startup_pipe, config_s[0]);
1.294 djm 1959: }
1.372 djm 1960:
1961: /* Executed child processes don't need these. */
1962: fcntl(sock_out, F_SETFD, FD_CLOEXEC);
1963: fcntl(sock_in, F_SETFD, FD_CLOEXEC);
1.64 markus 1964:
1.551 dtucker 1965: /* We will not restart on SIGHUP since it no longer makes sense. */
1.544 dtucker 1966: ssh_signal(SIGALRM, SIG_DFL);
1967: ssh_signal(SIGHUP, SIG_DFL);
1968: ssh_signal(SIGTERM, SIG_DFL);
1969: ssh_signal(SIGQUIT, SIG_DFL);
1970: ssh_signal(SIGCHLD, SIG_DFL);
1.150 markus 1971:
1.66 markus 1972: /*
1973: * Register our connection. This turns encryption off because we do
1974: * not have a key.
1975: */
1.525 djm 1976: if ((ssh = ssh_packet_set_connection(NULL, sock_in, sock_out)) == NULL)
1977: fatal("Unable to create connection");
1.527 djm 1978: the_active_state = ssh;
1.525 djm 1979: ssh_packet_set_server(ssh);
1.492 djm 1980:
1.466 djm 1981: check_ip_options(ssh);
1.309 djm 1982:
1.492 djm 1983: /* Prepare the channels layer */
1984: channel_init_channels(ssh);
1985: channel_set_af(ssh, options.address_family);
1986: process_permitopen(ssh, &options);
1987:
1.309 djm 1988: /* Set SO_KEEPALIVE if requested. */
1.525 djm 1989: if (options.tcp_keep_alive && ssh_packet_connection_is_on_socket(ssh) &&
1.537 deraadt 1990: setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof(on)) == -1)
1.309 djm 1991: error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno));
1.1 deraadt 1992:
1.466 djm 1993: if ((remote_port = ssh_remote_port(ssh)) < 0) {
1994: debug("ssh_remote_port failed");
1.310 markus 1995: cleanup_exit(255);
1996: }
1.316 dtucker 1997:
1998: /*
1.331 markus 1999: * The rest of the code depends on the fact that
1.466 djm 2000: * ssh_remote_ipaddr() caches the remote ip, even if
1.331 markus 2001: * the socket goes away.
2002: */
1.466 djm 2003: remote_ip = ssh_remote_ipaddr(ssh);
1.209 markus 2004:
1.496 djm 2005: rdomain = ssh_packet_rdomain_in(ssh);
2006:
1.64 markus 2007: /* Log the connection. */
1.447 dtucker 2008: laddr = get_local_ipaddr(sock_in);
1.497 djm 2009: verbose("Connection from %s port %d on %s port %d%s%s%s",
1.496 djm 2010: remote_ip, remote_port, laddr, ssh_local_port(ssh),
1.497 djm 2011: rdomain == NULL ? "" : " rdomain \"",
2012: rdomain == NULL ? "" : rdomain,
2013: rdomain == NULL ? "" : "\"");
1.447 dtucker 2014: free(laddr);
1.1 deraadt 2015:
1.66 markus 2016: /*
1.317 djm 2017: * We don't want to listen forever unless the other side
1.66 markus 2018: * successfully authenticates itself. So we set up an alarm which is
2019: * cleared after successful authentication. A limit of zero
1.317 djm 2020: * indicates no limit. Note that we don't set the alarm in debugging
1.66 markus 2021: * mode; it is just annoying to have the server exit just when you
2022: * are about to discover the bug.
2023: */
1.544 dtucker 2024: ssh_signal(SIGALRM, grace_alarm_handler);
1.64 markus 2025: if (!debug_flag)
2026: alarm(options.login_grace_time);
2027:
1.552 djm 2028: if ((r = kex_exchange_identification(ssh, -1,
2029: options.version_addendum)) != 0)
2030: sshpkt_fatal(ssh, r, "banner exchange");
1.520 djm 2031:
1.525 djm 2032: ssh_packet_set_nonblocking(ssh);
1.1 deraadt 2033:
1.278 markus 2034: /* allocate authentication context */
1.329 djm 2035: authctxt = xcalloc(1, sizeof(*authctxt));
1.525 djm 2036: ssh->authctxt = authctxt;
1.278 markus 2037:
2038: /* XXX global for cleanup, access from other modules */
2039: the_authctxt = authctxt;
1.506 djm 2040:
2041: /* Set default key authentication options */
2042: if ((auth_opts = sshauthopt_new_with_keys_defaults()) == NULL)
2043: fatal("allocation failed");
1.278 markus 2044:
1.307 otto 2045: /* prepare buffer to collect messages to display to user after login */
1.510 markus 2046: if ((loginmsg = sshbuf_new()) == NULL)
1.564 djm 2047: fatal_f("sshbuf_new failed");
1.374 dtucker 2048: auth_debug_reset();
1.307 otto 2049:
1.404 markus 2050: if (use_privsep) {
1.525 djm 2051: if (privsep_preauth(ssh) == 1)
1.237 markus 2052: goto authenticated;
1.472 markus 2053: } else if (have_agent) {
1.432 djm 2054: if ((r = ssh_get_authentication_socket(&auth_sock)) != 0) {
1.564 djm 2055: error_r(r, "Unable to get agent socket");
1.433 djm 2056: have_agent = 0;
1.432 djm 2057: }
2058: }
1.231 provos 2059:
1.77 markus 2060: /* perform the key exchange */
2061: /* authenticate user and start session */
1.525 djm 2062: do_ssh2_kex(ssh);
1.524 djm 2063: do_authentication2(ssh);
1.472 markus 2064:
1.237 markus 2065: /*
2066: * If we use privilege separation, the unprivileged child transfers
2067: * the current keystate and exits
2068: */
2069: if (use_privsep) {
1.527 djm 2070: mm_send_keystate(ssh, pmonitor);
1.525 djm 2071: ssh_packet_clear_keys(ssh);
1.231 provos 2072: exit(0);
1.237 markus 2073: }
1.231 provos 2074:
2075: authenticated:
1.318 djm 2076: /*
2077: * Cancel the alarm we set to limit the time taken for
2078: * authentication.
2079: */
2080: alarm(0);
1.544 dtucker 2081: ssh_signal(SIGALRM, SIG_DFL);
1.347 markus 2082: authctxt->authenticated = 1;
1.318 djm 2083: if (startup_pipe != -1) {
2084: close(startup_pipe);
2085: startup_pipe = -1;
2086: }
1.495 djm 2087:
2088: if (options.routing_domain != NULL)
2089: set_process_rdomain(ssh, options.routing_domain);
1.318 djm 2090:
1.234 markus 2091: /*
1.231 provos 2092: * In privilege separation, we fork another child and prepare
2093: * file descriptor passing.
2094: */
2095: if (use_privsep) {
1.525 djm 2096: privsep_postauth(ssh, authctxt);
1.237 markus 2097: /* the monitor process [priv] will not return */
1.231 provos 2098: }
1.360 dtucker 2099:
1.525 djm 2100: ssh_packet_set_timeout(ssh, options.client_alive_interval,
1.360 dtucker 2101: options.client_alive_count_max);
1.439 djm 2102:
2103: /* Try to send all our hostkeys to the client */
1.492 djm 2104: notify_hostkeys(ssh);
1.230 provos 2105:
1.278 markus 2106: /* Start session. */
1.492 djm 2107: do_authenticated(ssh, authctxt);
1.230 provos 2108:
1.64 markus 2109: /* The connection has been terminated. */
1.525 djm 2110: ssh_packet_get_bytes(ssh, &ibytes, &obytes);
1.381 djm 2111: verbose("Transferred: sent %llu, received %llu bytes",
2112: (unsigned long long)obytes, (unsigned long long)ibytes);
1.364 markus 2113:
2114: verbose("Closing connection to %.500s port %d", remote_ip, remote_port);
1.525 djm 2115: ssh_packet_close(ssh);
1.231 provos 2116:
2117: if (use_privsep)
2118: mm_terminate();
2119:
1.64 markus 2120: exit(0);
1.1 deraadt 2121: }
1.98 markus 2122:
1.435 markus 2123: int
1.527 djm 2124: sshd_hostkey_sign(struct ssh *ssh, struct sshkey *privkey,
2125: struct sshkey *pubkey, u_char **signature, size_t *slenp,
2126: const u_char *data, size_t dlen, const char *alg)
1.404 markus 2127: {
1.432 djm 2128: int r;
2129:
1.527 djm 2130: if (use_privsep) {
2131: if (privkey) {
2132: if (mm_sshkey_sign(ssh, privkey, signature, slenp,
1.561 djm 2133: data, dlen, alg, options.sk_provider, NULL,
1.542 djm 2134: ssh->compat) < 0)
1.564 djm 2135: fatal_f("privkey sign failed");
1.527 djm 2136: } else {
2137: if (mm_sshkey_sign(ssh, pubkey, signature, slenp,
1.561 djm 2138: data, dlen, alg, options.sk_provider, NULL,
1.542 djm 2139: ssh->compat) < 0)
1.564 djm 2140: fatal_f("pubkey sign failed");
1.527 djm 2141: }
1.404 markus 2142: } else {
1.527 djm 2143: if (privkey) {
2144: if (sshkey_sign(privkey, signature, slenp, data, dlen,
1.561 djm 2145: alg, options.sk_provider, NULL, ssh->compat) < 0)
1.564 djm 2146: fatal_f("privkey sign failed");
1.527 djm 2147: } else {
2148: if ((r = ssh_agent_sign(auth_sock, pubkey,
2149: signature, slenp, data, dlen, alg,
2150: ssh->compat)) != 0) {
1.564 djm 2151: fatal_fr(r, "agent sign failed");
1.527 djm 2152: }
2153: }
1.404 markus 2154: }
1.435 markus 2155: return 0;
1.404 markus 2156: }
2157:
1.452 djm 2158: /* SSH2 key exchange */
1.200 itojun 2159: static void
1.525 djm 2160: do_ssh2_kex(struct ssh *ssh)
1.98 markus 2161: {
1.422 markus 2162: char *myproposal[PROPOSAL_MAX] = { KEX_SERVER };
1.435 markus 2163: struct kex *kex;
1.437 markus 2164: int r;
1.102 markus 2165:
1.457 djm 2166: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
1.514 djm 2167: options.kex_algorithms);
1.457 djm 2168: myproposal[PROPOSAL_ENC_ALGS_CTOS] = compat_cipher_proposal(
1.514 djm 2169: options.ciphers);
1.457 djm 2170: myproposal[PROPOSAL_ENC_ALGS_STOC] = compat_cipher_proposal(
1.514 djm 2171: options.ciphers);
1.457 djm 2172: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
2173: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
2174:
1.312 markus 2175: if (options.compression == COMP_NONE) {
1.246 markus 2176: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.470 dtucker 2177: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
1.102 markus 2178: }
1.400 dtucker 2179:
2180: if (options.rekey_limit || options.rekey_interval)
1.525 djm 2181: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.481 dtucker 2182: options.rekey_interval);
1.327 deraadt 2183:
1.413 djm 2184: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = compat_pkalg_proposal(
1.514 djm 2185: list_hostkey_types());
1.134 markus 2186:
1.189 markus 2187: /* start key exchange */
1.525 djm 2188: if ((r = kex_setup(ssh, myproposal)) != 0)
1.564 djm 2189: fatal_r(r, "kex_setup");
1.525 djm 2190: kex = ssh->kex;
1.426 markus 2191: #ifdef WITH_OPENSSL
1.532 djm 2192: kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server;
2193: kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server;
2194: kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server;
2195: kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server;
2196: kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server;
1.263 markus 2197: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.324 djm 2198: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.532 djm 2199: kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
1.426 markus 2200: #endif
1.532 djm 2201: kex->kex[KEX_C25519_SHA256] = kex_gen_server;
2202: kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_server;
1.373 djm 2203: kex->load_host_public_key=&get_hostkey_public_by_type;
2204: kex->load_host_private_key=&get_hostkey_private_by_type;
1.231 provos 2205: kex->host_key_index=&get_hostkey_index;
1.404 markus 2206: kex->sign = sshd_hostkey_sign;
1.189 markus 2207:
1.525 djm 2208: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &kex->done);
1.187 markus 2209:
2210: session_id2 = kex->session_id;
2211: session_id2_len = kex->session_id_len;
1.129 provos 2212:
2213: #ifdef DEBUG_KEXDH
2214: /* send 1st encrypted/maced/compressed message */
1.553 djm 2215: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
2216: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
2217: (r = sshpkt_send(ssh)) != 0 ||
2218: (r = ssh_packet_write_wait(ssh)) != 0)
1.564 djm 2219: fatal_fr(r, "send test");
1.129 provos 2220: #endif
1.186 markus 2221: debug("KEX done");
1.278 markus 2222: }
2223:
2224: /* server specific fatal cleanup */
2225: void
2226: cleanup_exit(int i)
2227: {
1.527 djm 2228: if (the_active_state != NULL && the_authctxt != NULL) {
2229: do_cleanup(the_active_state, the_authctxt);
1.423 djm 2230: if (use_privsep && privsep_is_preauth &&
2231: pmonitor != NULL && pmonitor->m_pid > 1) {
1.386 djm 2232: debug("Killing privsep child %d", pmonitor->m_pid);
2233: if (kill(pmonitor->m_pid, SIGKILL) != 0 &&
1.564 djm 2234: errno != ESRCH) {
2235: error_f("kill(%d): %s", pmonitor->m_pid,
2236: strerror(errno));
2237: }
1.386 djm 2238: }
2239: }
1.278 markus 2240: _exit(i);
1.1 deraadt 2241: }
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