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3c0ef626 | 1 | /* |
2 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
3 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
4 | * All rights reserved | |
5 | * This program is the ssh daemon. It listens for connections from clients, | |
6 | * and performs authentication, executes use commands or shell, and forwards | |
7 | * information to/from the application to the user client over an encrypted | |
8 | * connection. This can also handle forwarding of X11, TCP/IP, and | |
9 | * authentication agent connections. | |
10 | * | |
11 | * As far as I am concerned, the code I have written for this software | |
12 | * can be used freely for any purpose. Any derived versions of this | |
13 | * software must be clearly marked as such, and if the derived work is | |
14 | * incompatible with the protocol description in the RFC file, it must be | |
15 | * called by a name other than "ssh" or "Secure Shell". | |
16 | * | |
17 | * SSH2 implementation: | |
510132b6 | 18 | * Privilege Separation: |
3c0ef626 | 19 | * |
510132b6 | 20 | * Copyright (c) 2000, 2001, 2002 Markus Friedl. All rights reserved. |
21 | * Copyright (c) 2002 Niels Provos. All rights reserved. | |
3c0ef626 | 22 | * |
23 | * Redistribution and use in source and binary forms, with or without | |
24 | * modification, are permitted provided that the following conditions | |
25 | * are met: | |
26 | * 1. Redistributions of source code must retain the above copyright | |
27 | * notice, this list of conditions and the following disclaimer. | |
28 | * 2. Redistributions in binary form must reproduce the above copyright | |
29 | * notice, this list of conditions and the following disclaimer in the | |
30 | * documentation and/or other materials provided with the distribution. | |
31 | * | |
32 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
33 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
34 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
35 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
36 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
37 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
38 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
39 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
40 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
41 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
42 | */ | |
43 | ||
44 | #include "includes.h" | |
2ce0bfe4 | 45 | RCSID("$OpenBSD: sshd.c,v 1.312 2005/07/25 11:59:40 markus Exp $"); |
3c0ef626 | 46 | |
47 | #include <openssl/dh.h> | |
48 | #include <openssl/bn.h> | |
1e608e42 | 49 | #include <openssl/md5.h> |
510132b6 | 50 | #include <openssl/rand.h> |
51 | #ifdef HAVE_SECUREWARE | |
52 | #include <sys/security.h> | |
53 | #include <prot.h> | |
54 | #endif | |
3c0ef626 | 55 | |
56 | #include "ssh.h" | |
57 | #include "ssh1.h" | |
58 | #include "ssh2.h" | |
59 | #include "xmalloc.h" | |
60 | #include "rsa.h" | |
61 | #include "sshpty.h" | |
62 | #include "packet.h" | |
3c0ef626 | 63 | #include "log.h" |
64 | #include "servconf.h" | |
65 | #include "uidswap.h" | |
66 | #include "compat.h" | |
67 | #include "buffer.h" | |
7e82606e | 68 | #include "bufaux.h" |
3c0ef626 | 69 | #include "cipher.h" |
70 | #include "kex.h" | |
71 | #include "key.h" | |
72 | #include "dh.h" | |
73 | #include "myproposal.h" | |
74 | #include "authfile.h" | |
75 | #include "pathnames.h" | |
76 | #include "atomicio.h" | |
77 | #include "canohost.h" | |
78 | #include "auth.h" | |
79 | #include "misc.h" | |
7e82606e | 80 | #include "msg.h" |
3c0ef626 | 81 | #include "dispatch.h" |
82 | #include "channels.h" | |
510132b6 | 83 | #include "session.h" |
84 | #include "monitor_mm.h" | |
85 | #include "monitor.h" | |
86 | #include "monitor_wrap.h" | |
87 | #include "monitor_fdpass.h" | |
3c0ef626 | 88 | |
5598e598 | 89 | #ifdef GSSAPI |
90 | #include "ssh-gss.h" | |
91 | #endif | |
92 | ||
0b582e46 | 93 | #ifdef GSSAPI |
94 | #include <openssl/md5.h> | |
95 | #include "bufaux.h" | |
96 | #endif /* GSSAPI */ | |
0b582e46 | 97 | |
3c0ef626 | 98 | #ifdef LIBWRAP |
99 | #include <tcpd.h> | |
100 | #include <syslog.h> | |
101 | int allow_severity = LOG_INFO; | |
102 | int deny_severity = LOG_WARNING; | |
103 | #endif /* LIBWRAP */ | |
104 | ||
105 | #ifndef O_NOCTTY | |
106 | #define O_NOCTTY 0 | |
107 | #endif | |
108 | ||
7e82606e | 109 | /* Re-exec fds */ |
110 | #define REEXEC_DEVCRYPTO_RESERVED_FD (STDERR_FILENO + 1) | |
111 | #define REEXEC_STARTUP_PIPE_FD (STDERR_FILENO + 2) | |
112 | #define REEXEC_CONFIG_PASS_FD (STDERR_FILENO + 3) | |
113 | #define REEXEC_MIN_FREE_FD (STDERR_FILENO + 4) | |
114 | ||
3c0ef626 | 115 | extern char *__progname; |
3c0ef626 | 116 | |
117 | /* Server configuration options. */ | |
118 | ServerOptions options; | |
119 | ||
120 | /* Name of the server configuration file. */ | |
121 | char *config_file_name = _PATH_SERVER_CONFIG_FILE; | |
122 | ||
3c0ef626 | 123 | /* |
124 | * Debug mode flag. This can be set on the command line. If debug | |
125 | * mode is enabled, extra debugging output will be sent to the system | |
126 | * log, the daemon will not go to background, and will exit after processing | |
127 | * the first connection. | |
128 | */ | |
129 | int debug_flag = 0; | |
130 | ||
131 | /* Flag indicating that the daemon should only test the configuration and keys. */ | |
132 | int test_flag = 0; | |
133 | ||
134 | /* Flag indicating that the daemon is being started from inetd. */ | |
135 | int inetd_flag = 0; | |
136 | ||
137 | /* Flag indicating that sshd should not detach and become a daemon. */ | |
138 | int no_daemon_flag = 0; | |
139 | ||
140 | /* debug goes to stderr unless inetd_flag is set */ | |
141 | int log_stderr = 0; | |
142 | ||
143 | /* Saved arguments to main(). */ | |
144 | char **saved_argv; | |
145 | int saved_argc; | |
146 | ||
7e82606e | 147 | /* re-exec */ |
148 | int rexeced_flag = 0; | |
149 | int rexec_flag = 1; | |
150 | int rexec_argc = 0; | |
151 | char **rexec_argv; | |
152 | ||
3c0ef626 | 153 | /* |
154 | * The sockets that the server is listening; this is used in the SIGHUP | |
155 | * signal handler. | |
156 | */ | |
157 | #define MAX_LISTEN_SOCKS 16 | |
158 | int listen_socks[MAX_LISTEN_SOCKS]; | |
159 | int num_listen_socks = 0; | |
160 | ||
161 | /* | |
162 | * the client's version string, passed by sshd2 in compat mode. if != NULL, | |
163 | * sshd will skip the version-number exchange | |
164 | */ | |
165 | char *client_version_string = NULL; | |
166 | char *server_version_string = NULL; | |
167 | ||
168 | /* for rekeying XXX fixme */ | |
169 | Kex *xxx_kex; | |
170 | ||
171 | /* | |
172 | * Any really sensitive data in the application is contained in this | |
173 | * structure. The idea is that this structure could be locked into memory so | |
174 | * that the pages do not get written into swap. However, there are some | |
175 | * problems. The private key contains BIGNUMs, and we do not (in principle) | |
176 | * have access to the internals of them, and locking just the structure is | |
177 | * not very useful. Currently, memory locking is not implemented. | |
178 | */ | |
179 | struct { | |
180 | Key *server_key; /* ephemeral server key */ | |
181 | Key *ssh1_host_key; /* ssh1 host key */ | |
182 | Key **host_keys; /* all private host keys */ | |
183 | int have_ssh1_key; | |
184 | int have_ssh2_key; | |
185 | u_char ssh1_cookie[SSH_SESSION_KEY_LENGTH]; | |
186 | } sensitive_data; | |
187 | ||
188 | /* | |
189 | * Flag indicating whether the RSA server key needs to be regenerated. | |
190 | * Is set in the SIGALRM handler and cleared when the key is regenerated. | |
191 | */ | |
1e608e42 | 192 | static volatile sig_atomic_t key_do_regen = 0; |
3c0ef626 | 193 | |
194 | /* This is set to true when a signal is received. */ | |
1e608e42 | 195 | static volatile sig_atomic_t received_sighup = 0; |
196 | static volatile sig_atomic_t received_sigterm = 0; | |
3c0ef626 | 197 | |
198 | /* session identifier, used by RSA-auth */ | |
199 | u_char session_id[16]; | |
200 | ||
201 | /* same for ssh2 */ | |
202 | u_char *session_id2 = NULL; | |
7cac2b65 | 203 | u_int session_id2_len = 0; |
3c0ef626 | 204 | |
205 | /* record remote hostname or ip */ | |
206 | u_int utmp_len = MAXHOSTNAMELEN; | |
207 | ||
1e608e42 | 208 | /* options.max_startup sized array of fd ints */ |
209 | int *startup_pipes = NULL; | |
210 | int startup_pipe; /* in child */ | |
211 | ||
510132b6 | 212 | /* variables used for privilege separation */ |
bfe49944 | 213 | int use_privsep; |
540d72c3 | 214 | struct monitor *pmonitor = NULL; |
510132b6 | 215 | |
540d72c3 | 216 | /* global authentication context */ |
217 | Authctxt *the_authctxt = NULL; | |
218 | ||
7e82606e | 219 | /* message to be displayed after login */ |
220 | Buffer loginmsg; | |
221 | ||
3c0ef626 | 222 | /* Prototypes for various functions defined later in this file. */ |
223 | void destroy_sensitive_data(void); | |
510132b6 | 224 | void demote_sensitive_data(void); |
3c0ef626 | 225 | |
226 | static void do_ssh1_kex(void); | |
227 | static void do_ssh2_kex(void); | |
228 | ||
229 | /* | |
230 | * Close all listening sockets | |
231 | */ | |
232 | static void | |
233 | close_listen_socks(void) | |
234 | { | |
235 | int i; | |
276b07a3 | 236 | |
3c0ef626 | 237 | for (i = 0; i < num_listen_socks; i++) |
238 | close(listen_socks[i]); | |
239 | num_listen_socks = -1; | |
240 | } | |
241 | ||
1e608e42 | 242 | static void |
243 | close_startup_pipes(void) | |
244 | { | |
245 | int i; | |
276b07a3 | 246 | |
1e608e42 | 247 | if (startup_pipes) |
248 | for (i = 0; i < options.max_startups; i++) | |
249 | if (startup_pipes[i] != -1) | |
250 | close(startup_pipes[i]); | |
251 | } | |
252 | ||
3c0ef626 | 253 | /* |
254 | * Signal handler for SIGHUP. Sshd execs itself when it receives SIGHUP; | |
255 | * the effect is to reread the configuration file (and to regenerate | |
256 | * the server key). | |
257 | */ | |
258 | static void | |
259 | sighup_handler(int sig) | |
260 | { | |
1e608e42 | 261 | int save_errno = errno; |
262 | ||
3c0ef626 | 263 | received_sighup = 1; |
264 | signal(SIGHUP, sighup_handler); | |
1e608e42 | 265 | errno = save_errno; |
3c0ef626 | 266 | } |
267 | ||
268 | /* | |
269 | * Called from the main program after receiving SIGHUP. | |
270 | * Restarts the server. | |
271 | */ | |
272 | static void | |
273 | sighup_restart(void) | |
274 | { | |
7cac2b65 | 275 | logit("Received SIGHUP; restarting."); |
3c0ef626 | 276 | close_listen_socks(); |
1e608e42 | 277 | close_startup_pipes(); |
3c0ef626 | 278 | execv(saved_argv[0], saved_argv); |
7cac2b65 | 279 | logit("RESTART FAILED: av[0]='%.100s', error: %.100s.", saved_argv[0], |
276b07a3 | 280 | strerror(errno)); |
3c0ef626 | 281 | exit(1); |
282 | } | |
283 | ||
284 | /* | |
285 | * Generic signal handler for terminating signals in the master daemon. | |
286 | */ | |
287 | static void | |
288 | sigterm_handler(int sig) | |
289 | { | |
290 | received_sigterm = sig; | |
291 | } | |
292 | ||
293 | /* | |
294 | * SIGCHLD handler. This is called whenever a child dies. This will then | |
295 | * reap any zombies left by exited children. | |
296 | */ | |
297 | static void | |
298 | main_sigchld_handler(int sig) | |
299 | { | |
300 | int save_errno = errno; | |
276b07a3 | 301 | pid_t pid; |
3c0ef626 | 302 | int status; |
303 | ||
510132b6 | 304 | while ((pid = waitpid(-1, &status, WNOHANG)) > 0 || |
305 | (pid < 0 && errno == EINTR)) | |
3c0ef626 | 306 | ; |
307 | ||
308 | signal(SIGCHLD, main_sigchld_handler); | |
309 | errno = save_errno; | |
310 | } | |
311 | ||
312 | /* | |
313 | * Signal handler for the alarm after the login grace period has expired. | |
314 | */ | |
315 | static void | |
316 | grace_alarm_handler(int sig) | |
317 | { | |
318 | /* XXX no idea how fix this signal handler */ | |
319 | ||
540d72c3 | 320 | if (use_privsep && pmonitor != NULL && pmonitor->m_pid > 0) |
321 | kill(pmonitor->m_pid, SIGALRM); | |
322 | ||
3c0ef626 | 323 | /* Log error and exit. */ |
d03f4262 | 324 | fatal("Timeout before authentication for %s", get_remote_ipaddr()); |
3c0ef626 | 325 | } |
326 | ||
327 | /* | |
328 | * Signal handler for the key regeneration alarm. Note that this | |
329 | * alarm only occurs in the daemon waiting for connections, and it does not | |
330 | * do anything with the private key or random state before forking. | |
331 | * Thus there should be no concurrency control/asynchronous execution | |
332 | * problems. | |
333 | */ | |
334 | static void | |
335 | generate_ephemeral_server_key(void) | |
336 | { | |
d03f4262 | 337 | u_int32_t rnd = 0; |
3c0ef626 | 338 | int i; |
339 | ||
340 | verbose("Generating %s%d bit RSA key.", | |
341 | sensitive_data.server_key ? "new " : "", options.server_key_bits); | |
342 | if (sensitive_data.server_key != NULL) | |
343 | key_free(sensitive_data.server_key); | |
344 | sensitive_data.server_key = key_generate(KEY_RSA1, | |
345 | options.server_key_bits); | |
346 | verbose("RSA key generation complete."); | |
347 | ||
348 | for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) { | |
349 | if (i % 4 == 0) | |
d03f4262 | 350 | rnd = arc4random(); |
351 | sensitive_data.ssh1_cookie[i] = rnd & 0xff; | |
352 | rnd >>= 8; | |
3c0ef626 | 353 | } |
354 | arc4random_stir(); | |
355 | } | |
356 | ||
357 | static void | |
358 | key_regeneration_alarm(int sig) | |
359 | { | |
360 | int save_errno = errno; | |
276b07a3 | 361 | |
3c0ef626 | 362 | signal(SIGALRM, SIG_DFL); |
363 | errno = save_errno; | |
364 | key_do_regen = 1; | |
365 | } | |
366 | ||
367 | static void | |
368 | sshd_exchange_identification(int sock_in, int sock_out) | |
369 | { | |
2ce0bfe4 | 370 | u_int i; |
371 | int mismatch; | |
3c0ef626 | 372 | int remote_major, remote_minor; |
373 | int major, minor; | |
374 | char *s; | |
375 | char buf[256]; /* Must not be larger than remote_version. */ | |
376 | char remote_version[256]; /* Must be at least as big as buf. */ | |
377 | ||
378 | if ((options.protocol & SSH_PROTO_1) && | |
379 | (options.protocol & SSH_PROTO_2)) { | |
380 | major = PROTOCOL_MAJOR_1; | |
381 | minor = 99; | |
382 | } else if (options.protocol & SSH_PROTO_2) { | |
383 | major = PROTOCOL_MAJOR_2; | |
384 | minor = PROTOCOL_MINOR_2; | |
385 | } else { | |
386 | major = PROTOCOL_MAJOR_1; | |
387 | minor = PROTOCOL_MINOR_1; | |
388 | } | |
389 | snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n", major, minor, SSH_VERSION); | |
390 | server_version_string = xstrdup(buf); | |
391 | ||
7cac2b65 | 392 | /* Send our protocol version identification. */ |
393 | if (atomicio(vwrite, sock_out, server_version_string, | |
394 | strlen(server_version_string)) | |
395 | != strlen(server_version_string)) { | |
396 | logit("Could not write ident string to %s", get_remote_ipaddr()); | |
540d72c3 | 397 | cleanup_exit(255); |
7cac2b65 | 398 | } |
399 | ||
400 | /* Read other sides version identification. */ | |
401 | memset(buf, 0, sizeof(buf)); | |
402 | for (i = 0; i < sizeof(buf) - 1; i++) { | |
403 | if (atomicio(read, sock_in, &buf[i], 1) != 1) { | |
404 | logit("Did not receive identification string from %s", | |
405 | get_remote_ipaddr()); | |
540d72c3 | 406 | cleanup_exit(255); |
3c0ef626 | 407 | } |
7cac2b65 | 408 | if (buf[i] == '\r') { |
409 | buf[i] = 0; | |
410 | /* Kludge for F-Secure Macintosh < 1.0.2 */ | |
411 | if (i == 12 && | |
412 | strncmp(buf, "SSH-1.5-W1.0", 12) == 0) | |
3c0ef626 | 413 | break; |
7cac2b65 | 414 | continue; |
415 | } | |
416 | if (buf[i] == '\n') { | |
417 | buf[i] = 0; | |
418 | break; | |
3c0ef626 | 419 | } |
3c0ef626 | 420 | } |
7cac2b65 | 421 | buf[sizeof(buf) - 1] = 0; |
422 | client_version_string = xstrdup(buf); | |
3c0ef626 | 423 | |
424 | /* | |
425 | * Check that the versions match. In future this might accept | |
426 | * several versions and set appropriate flags to handle them. | |
427 | */ | |
428 | if (sscanf(client_version_string, "SSH-%d.%d-%[^\n]\n", | |
429 | &remote_major, &remote_minor, remote_version) != 3) { | |
430 | s = "Protocol mismatch.\n"; | |
7cac2b65 | 431 | (void) atomicio(vwrite, sock_out, s, strlen(s)); |
3c0ef626 | 432 | close(sock_in); |
433 | close(sock_out); | |
7cac2b65 | 434 | logit("Bad protocol version identification '%.100s' from %s", |
3c0ef626 | 435 | client_version_string, get_remote_ipaddr()); |
540d72c3 | 436 | cleanup_exit(255); |
3c0ef626 | 437 | } |
438 | debug("Client protocol version %d.%d; client software version %.100s", | |
1e608e42 | 439 | remote_major, remote_minor, remote_version); |
3c0ef626 | 440 | |
441 | compat_datafellows(remote_version); | |
442 | ||
d03f4262 | 443 | if (datafellows & SSH_BUG_PROBE) { |
7cac2b65 | 444 | logit("probed from %s with %s. Don't panic.", |
d03f4262 | 445 | get_remote_ipaddr(), client_version_string); |
540d72c3 | 446 | cleanup_exit(255); |
d03f4262 | 447 | } |
448 | ||
3c0ef626 | 449 | if (datafellows & SSH_BUG_SCANNER) { |
7cac2b65 | 450 | logit("scanned from %s with %s. Don't panic.", |
3c0ef626 | 451 | get_remote_ipaddr(), client_version_string); |
540d72c3 | 452 | cleanup_exit(255); |
3c0ef626 | 453 | } |
454 | ||
455 | mismatch = 0; | |
1e608e42 | 456 | switch (remote_major) { |
3c0ef626 | 457 | case 1: |
458 | if (remote_minor == 99) { | |
459 | if (options.protocol & SSH_PROTO_2) | |
460 | enable_compat20(); | |
461 | else | |
462 | mismatch = 1; | |
463 | break; | |
464 | } | |
465 | if (!(options.protocol & SSH_PROTO_1)) { | |
466 | mismatch = 1; | |
467 | break; | |
468 | } | |
469 | if (remote_minor < 3) { | |
470 | packet_disconnect("Your ssh version is too old and " | |
471 | "is no longer supported. Please install a newer version."); | |
472 | } else if (remote_minor == 3) { | |
473 | /* note that this disables agent-forwarding */ | |
474 | enable_compat13(); | |
475 | } | |
476 | break; | |
477 | case 2: | |
478 | if (options.protocol & SSH_PROTO_2) { | |
479 | enable_compat20(); | |
480 | break; | |
481 | } | |
482 | /* FALLTHROUGH */ | |
483 | default: | |
484 | mismatch = 1; | |
485 | break; | |
486 | } | |
487 | chop(server_version_string); | |
488 | debug("Local version string %.200s", server_version_string); | |
489 | ||
490 | if (mismatch) { | |
491 | s = "Protocol major versions differ.\n"; | |
7cac2b65 | 492 | (void) atomicio(vwrite, sock_out, s, strlen(s)); |
3c0ef626 | 493 | close(sock_in); |
494 | close(sock_out); | |
7cac2b65 | 495 | logit("Protocol major versions differ for %s: %.200s vs. %.200s", |
3c0ef626 | 496 | get_remote_ipaddr(), |
497 | server_version_string, client_version_string); | |
540d72c3 | 498 | cleanup_exit(255); |
3c0ef626 | 499 | } |
500 | } | |
501 | ||
3c0ef626 | 502 | /* Destroy the host and server keys. They will no longer be needed. */ |
503 | void | |
504 | destroy_sensitive_data(void) | |
505 | { | |
506 | int i; | |
507 | ||
508 | if (sensitive_data.server_key) { | |
509 | key_free(sensitive_data.server_key); | |
510 | sensitive_data.server_key = NULL; | |
511 | } | |
1e608e42 | 512 | for (i = 0; i < options.num_host_key_files; i++) { |
3c0ef626 | 513 | if (sensitive_data.host_keys[i]) { |
514 | key_free(sensitive_data.host_keys[i]); | |
515 | sensitive_data.host_keys[i] = NULL; | |
516 | } | |
517 | } | |
518 | sensitive_data.ssh1_host_key = NULL; | |
519 | memset(sensitive_data.ssh1_cookie, 0, SSH_SESSION_KEY_LENGTH); | |
520 | } | |
521 | ||
510132b6 | 522 | /* Demote private to public keys for network child */ |
523 | void | |
524 | demote_sensitive_data(void) | |
525 | { | |
526 | Key *tmp; | |
527 | int i; | |
528 | ||
529 | if (sensitive_data.server_key) { | |
530 | tmp = key_demote(sensitive_data.server_key); | |
531 | key_free(sensitive_data.server_key); | |
532 | sensitive_data.server_key = tmp; | |
533 | } | |
534 | ||
535 | for (i = 0; i < options.num_host_key_files; i++) { | |
536 | if (sensitive_data.host_keys[i]) { | |
537 | tmp = key_demote(sensitive_data.host_keys[i]); | |
538 | key_free(sensitive_data.host_keys[i]); | |
539 | sensitive_data.host_keys[i] = tmp; | |
540 | if (tmp->type == KEY_RSA1) | |
541 | sensitive_data.ssh1_host_key = tmp; | |
542 | } | |
543 | } | |
544 | ||
545 | /* We do not clear ssh1_host key and cookie. XXX - Okay Niels? */ | |
546 | } | |
547 | ||
548 | static void | |
549 | privsep_preauth_child(void) | |
550 | { | |
d03f4262 | 551 | u_int32_t rnd[256]; |
552 | gid_t gidset[1]; | |
510132b6 | 553 | struct passwd *pw; |
276b07a3 | 554 | int i; |
510132b6 | 555 | |
556 | /* Enable challenge-response authentication for privilege separation */ | |
557 | privsep_challenge_enable(); | |
558 | ||
559 | for (i = 0; i < 256; i++) | |
d03f4262 | 560 | rnd[i] = arc4random(); |
561 | RAND_seed(rnd, sizeof(rnd)); | |
510132b6 | 562 | |
563 | /* Demote the private keys to public keys. */ | |
564 | demote_sensitive_data(); | |
565 | ||
566 | if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) | |
567 | fatal("Privilege separation user %s does not exist", | |
568 | SSH_PRIVSEP_USER); | |
569 | memset(pw->pw_passwd, 0, strlen(pw->pw_passwd)); | |
570 | endpwent(); | |
571 | ||
d03f4262 | 572 | /* Change our root directory */ |
510132b6 | 573 | if (chroot(_PATH_PRIVSEP_CHROOT_DIR) == -1) |
574 | fatal("chroot(\"%s\"): %s", _PATH_PRIVSEP_CHROOT_DIR, | |
575 | strerror(errno)); | |
576 | if (chdir("/") == -1) | |
577 | fatal("chdir(\"/\"): %s", strerror(errno)); | |
578 | ||
579 | /* Drop our privileges */ | |
580 | debug3("privsep user:group %u:%u", (u_int)pw->pw_uid, | |
581 | (u_int)pw->pw_gid); | |
276b07a3 | 582 | #if 0 |
12a403af | 583 | /* XXX not ready, too heavy after chroot */ |
510132b6 | 584 | do_setusercontext(pw); |
276b07a3 | 585 | #else |
586 | gidset[0] = pw->pw_gid; | |
276b07a3 | 587 | if (setgroups(1, gidset) < 0) |
588 | fatal("setgroups: %.100s", strerror(errno)); | |
589 | permanently_set_uid(pw); | |
590 | #endif | |
510132b6 | 591 | } |
592 | ||
540d72c3 | 593 | static int |
594 | privsep_preauth(Authctxt *authctxt) | |
510132b6 | 595 | { |
510132b6 | 596 | int status; |
597 | pid_t pid; | |
598 | ||
599 | /* Set up unprivileged child process to deal with network data */ | |
600 | pmonitor = monitor_init(); | |
601 | /* Store a pointer to the kex for later rekeying */ | |
602 | pmonitor->m_pkex = &xxx_kex; | |
603 | ||
604 | pid = fork(); | |
605 | if (pid == -1) { | |
606 | fatal("fork of unprivileged child failed"); | |
607 | } else if (pid != 0) { | |
44a053a3 | 608 | debug2("Network child is on pid %ld", (long)pid); |
510132b6 | 609 | |
610 | close(pmonitor->m_recvfd); | |
540d72c3 | 611 | pmonitor->m_pid = pid; |
612 | monitor_child_preauth(authctxt, pmonitor); | |
510132b6 | 613 | close(pmonitor->m_sendfd); |
614 | ||
615 | /* Sync memory */ | |
616 | monitor_sync(pmonitor); | |
617 | ||
618 | /* Wait for the child's exit status */ | |
619 | while (waitpid(pid, &status, 0) < 0) | |
620 | if (errno != EINTR) | |
621 | break; | |
540d72c3 | 622 | return (1); |
510132b6 | 623 | } else { |
624 | /* child */ | |
625 | ||
626 | close(pmonitor->m_sendfd); | |
627 | ||
628 | /* Demote the child */ | |
629 | if (getuid() == 0 || geteuid() == 0) | |
630 | privsep_preauth_child(); | |
631 | setproctitle("%s", "[net]"); | |
632 | } | |
540d72c3 | 633 | return (0); |
510132b6 | 634 | } |
635 | ||
636 | static void | |
637 | privsep_postauth(Authctxt *authctxt) | |
638 | { | |
d03f4262 | 639 | #ifdef DISABLE_FD_PASSING |
276b07a3 | 640 | if (1) { |
641 | #else | |
510132b6 | 642 | if (authctxt->pw->pw_uid == 0 || options.use_login) { |
276b07a3 | 643 | #endif |
510132b6 | 644 | /* File descriptor passing is broken or root login */ |
645 | monitor_apply_keystate(pmonitor); | |
646 | use_privsep = 0; | |
647 | return; | |
648 | } | |
649 | ||
650 | /* Authentication complete */ | |
651 | alarm(0); | |
652 | if (startup_pipe != -1) { | |
653 | close(startup_pipe); | |
654 | startup_pipe = -1; | |
655 | } | |
656 | ||
657 | /* New socket pair */ | |
658 | monitor_reinit(pmonitor); | |
659 | ||
660 | pmonitor->m_pid = fork(); | |
661 | if (pmonitor->m_pid == -1) | |
662 | fatal("fork of unprivileged child failed"); | |
663 | else if (pmonitor->m_pid != 0) { | |
44a053a3 | 664 | debug2("User child is on pid %ld", (long)pmonitor->m_pid); |
510132b6 | 665 | close(pmonitor->m_recvfd); |
7e82606e | 666 | buffer_clear(&loginmsg); |
510132b6 | 667 | monitor_child_postauth(pmonitor); |
668 | ||
669 | /* NEVERREACHED */ | |
670 | exit(0); | |
671 | } | |
672 | ||
673 | close(pmonitor->m_sendfd); | |
674 | ||
675 | /* Demote the private keys to public keys. */ | |
676 | demote_sensitive_data(); | |
677 | ||
678 | /* Drop privileges */ | |
679 | do_setusercontext(authctxt->pw); | |
680 | ||
681 | /* It is safe now to apply the key state */ | |
682 | monitor_apply_keystate(pmonitor); | |
2ce0bfe4 | 683 | |
684 | /* | |
685 | * Tell the packet layer that authentication was successful, since | |
686 | * this information is not part of the key state. | |
687 | */ | |
688 | packet_set_authenticated(); | |
510132b6 | 689 | } |
690 | ||
3c0ef626 | 691 | static char * |
692 | list_hostkey_types(void) | |
693 | { | |
1e608e42 | 694 | Buffer b; |
540d72c3 | 695 | const char *p; |
696 | char *ret; | |
3c0ef626 | 697 | int i; |
1e608e42 | 698 | |
699 | buffer_init(&b); | |
700 | for (i = 0; i < options.num_host_key_files; i++) { | |
3c0ef626 | 701 | Key *key = sensitive_data.host_keys[i]; |
702 | if (key == NULL) | |
703 | continue; | |
1e608e42 | 704 | switch (key->type) { |
3c0ef626 | 705 | case KEY_RSA: |
706 | case KEY_DSA: | |
1e608e42 | 707 | if (buffer_len(&b) > 0) |
708 | buffer_append(&b, ",", 1); | |
709 | p = key_ssh_name(key); | |
710 | buffer_append(&b, p, strlen(p)); | |
3c0ef626 | 711 | break; |
712 | } | |
713 | } | |
1e608e42 | 714 | buffer_append(&b, "\0", 1); |
540d72c3 | 715 | ret = xstrdup(buffer_ptr(&b)); |
1e608e42 | 716 | buffer_free(&b); |
540d72c3 | 717 | debug("list_hostkey_types: %s", ret); |
718 | return ret; | |
3c0ef626 | 719 | } |
720 | ||
510132b6 | 721 | Key * |
3c0ef626 | 722 | get_hostkey_by_type(int type) |
723 | { | |
724 | int i; | |
276b07a3 | 725 | |
1e608e42 | 726 | for (i = 0; i < options.num_host_key_files; i++) { |
3c0ef626 | 727 | Key *key = sensitive_data.host_keys[i]; |
728 | if (key != NULL && key->type == type) | |
729 | return key; | |
730 | } | |
731 | return NULL; | |
732 | } | |
733 | ||
510132b6 | 734 | Key * |
735 | get_hostkey_by_index(int ind) | |
736 | { | |
737 | if (ind < 0 || ind >= options.num_host_key_files) | |
738 | return (NULL); | |
739 | return (sensitive_data.host_keys[ind]); | |
740 | } | |
741 | ||
742 | int | |
743 | get_hostkey_index(Key *key) | |
744 | { | |
745 | int i; | |
276b07a3 | 746 | |
510132b6 | 747 | for (i = 0; i < options.num_host_key_files; i++) { |
748 | if (key == sensitive_data.host_keys[i]) | |
749 | return (i); | |
750 | } | |
751 | return (-1); | |
752 | } | |
753 | ||
3c0ef626 | 754 | /* |
755 | * returns 1 if connection should be dropped, 0 otherwise. | |
756 | * dropping starts at connection #max_startups_begin with a probability | |
757 | * of (max_startups_rate/100). the probability increases linearly until | |
758 | * all connections are dropped for startups > max_startups | |
759 | */ | |
760 | static int | |
761 | drop_connection(int startups) | |
762 | { | |
dfddba3d | 763 | int p, r; |
3c0ef626 | 764 | |
765 | if (startups < options.max_startups_begin) | |
766 | return 0; | |
767 | if (startups >= options.max_startups) | |
768 | return 1; | |
769 | if (options.max_startups_rate == 100) | |
770 | return 1; | |
771 | ||
772 | p = 100 - options.max_startups_rate; | |
773 | p *= startups - options.max_startups_begin; | |
dfddba3d | 774 | p /= options.max_startups - options.max_startups_begin; |
3c0ef626 | 775 | p += options.max_startups_rate; |
dfddba3d | 776 | r = arc4random() % 100; |
3c0ef626 | 777 | |
dfddba3d | 778 | debug("drop_connection: p %d, r %d", p, r); |
3c0ef626 | 779 | return (r < p) ? 1 : 0; |
780 | } | |
781 | ||
1e608e42 | 782 | static void |
783 | usage(void) | |
784 | { | |
12a403af | 785 | fprintf(stderr, "%s, %s\n", |
dfddba3d | 786 | SSH_RELEASE, SSLeay_version(SSLEAY_VERSION)); |
12a403af | 787 | fprintf(stderr, |
788 | "usage: sshd [-46Ddeiqt] [-b bits] [-f config_file] [-g login_grace_time]\n" | |
789 | " [-h host_key_file] [-k key_gen_time] [-o option] [-p port] [-u len]\n" | |
790 | ); | |
1e608e42 | 791 | exit(1); |
792 | } | |
3c0ef626 | 793 | |
7e82606e | 794 | static void |
795 | send_rexec_state(int fd, Buffer *conf) | |
796 | { | |
797 | Buffer m; | |
798 | ||
799 | debug3("%s: entering fd = %d config len %d", __func__, fd, | |
800 | buffer_len(conf)); | |
801 | ||
802 | /* | |
803 | * Protocol from reexec master to child: | |
804 | * string configuration | |
805 | * u_int ephemeral_key_follows | |
806 | * bignum e (only if ephemeral_key_follows == 1) | |
807 | * bignum n " | |
808 | * bignum d " | |
809 | * bignum iqmp " | |
810 | * bignum p " | |
811 | * bignum q " | |
812 | */ | |
813 | buffer_init(&m); | |
814 | buffer_put_cstring(&m, buffer_ptr(conf)); | |
815 | ||
816 | if (sensitive_data.server_key != NULL && | |
817 | sensitive_data.server_key->type == KEY_RSA1) { | |
818 | buffer_put_int(&m, 1); | |
819 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->e); | |
820 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->n); | |
821 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->d); | |
822 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->iqmp); | |
823 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->p); | |
824 | buffer_put_bignum(&m, sensitive_data.server_key->rsa->q); | |
825 | } else | |
826 | buffer_put_int(&m, 0); | |
827 | ||
828 | if (ssh_msg_send(fd, 0, &m) == -1) | |
829 | fatal("%s: ssh_msg_send failed", __func__); | |
830 | ||
831 | buffer_free(&m); | |
832 | ||
833 | debug3("%s: done", __func__); | |
834 | } | |
835 | ||
836 | static void | |
837 | recv_rexec_state(int fd, Buffer *conf) | |
838 | { | |
839 | Buffer m; | |
840 | char *cp; | |
841 | u_int len; | |
842 | ||
843 | debug3("%s: entering fd = %d", __func__, fd); | |
844 | ||
845 | buffer_init(&m); | |
846 | ||
847 | if (ssh_msg_recv(fd, &m) == -1) | |
848 | fatal("%s: ssh_msg_recv failed", __func__); | |
849 | if (buffer_get_char(&m) != 0) | |
850 | fatal("%s: rexec version mismatch", __func__); | |
851 | ||
852 | cp = buffer_get_string(&m, &len); | |
853 | if (conf != NULL) | |
854 | buffer_append(conf, cp, len + 1); | |
855 | xfree(cp); | |
856 | ||
857 | if (buffer_get_int(&m)) { | |
858 | if (sensitive_data.server_key != NULL) | |
859 | key_free(sensitive_data.server_key); | |
860 | sensitive_data.server_key = key_new_private(KEY_RSA1); | |
861 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->e); | |
862 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->n); | |
863 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->d); | |
864 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->iqmp); | |
865 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->p); | |
866 | buffer_get_bignum(&m, sensitive_data.server_key->rsa->q); | |
867 | rsa_generate_additional_parameters( | |
868 | sensitive_data.server_key->rsa); | |
869 | } | |
870 | buffer_free(&m); | |
871 | ||
872 | debug3("%s: done", __func__); | |
873 | } | |
874 | ||
3c0ef626 | 875 | /* |
876 | * Main program for the daemon. | |
877 | */ | |
878 | int | |
879 | main(int ac, char **av) | |
880 | { | |
881 | extern char *optarg; | |
882 | extern int optind; | |
7e82606e | 883 | int opt, j, i, fdsetsz, on = 1; |
884 | int sock_in = -1, sock_out = -1, newsock = -1; | |
3c0ef626 | 885 | pid_t pid; |
886 | socklen_t fromlen; | |
887 | fd_set *fdset; | |
888 | struct sockaddr_storage from; | |
889 | const char *remote_ip; | |
890 | int remote_port; | |
891 | FILE *f; | |
3c0ef626 | 892 | struct addrinfo *ai; |
893 | char ntop[NI_MAXHOST], strport[NI_MAXSERV]; | |
540d72c3 | 894 | char *line; |
3c0ef626 | 895 | int listen_sock, maxfd; |
dfddba3d | 896 | int startup_p[2] = { -1 , -1 }, config_s[2] = { -1 , -1 }; |
3c0ef626 | 897 | int startups = 0; |
898 | Key *key; | |
540d72c3 | 899 | Authctxt *authctxt; |
3c0ef626 | 900 | int ret, key_used = 0; |
7e82606e | 901 | Buffer cfg; |
3c0ef626 | 902 | |
510132b6 | 903 | #ifdef HAVE_SECUREWARE |
904 | (void)set_auth_parameters(ac, av); | |
905 | #endif | |
7cac2b65 | 906 | __progname = ssh_get_progname(av[0]); |
3c0ef626 | 907 | init_rng(); |
908 | ||
bfe49944 | 909 | /* Save argv. Duplicate so setproctitle emulation doesn't clobber it */ |
3c0ef626 | 910 | saved_argc = ac; |
7e82606e | 911 | rexec_argc = ac; |
7cac2b65 | 912 | saved_argv = xmalloc(sizeof(*saved_argv) * (ac + 1)); |
bfe49944 | 913 | for (i = 0; i < ac; i++) |
914 | saved_argv[i] = xstrdup(av[i]); | |
7cac2b65 | 915 | saved_argv[i] = NULL; |
bfe49944 | 916 | |
917 | #ifndef HAVE_SETPROCTITLE | |
918 | /* Prepare for later setproctitle emulation */ | |
919 | compat_init_setproctitle(ac, av); | |
7cac2b65 | 920 | av = saved_argv; |
bfe49944 | 921 | #endif |
3c0ef626 | 922 | |
12a403af | 923 | if (geteuid() == 0 && setgroups(0, NULL) == -1) |
924 | debug("setgroups(): %.200s", strerror(errno)); | |
925 | ||
3c0ef626 | 926 | /* Initialize configuration options to their default values. */ |
927 | initialize_server_options(&options); | |
928 | ||
929 | /* Parse command-line arguments. */ | |
7e82606e | 930 | while ((opt = getopt(ac, av, "f:p:b:k:h:g:u:o:dDeiqrtQR46")) != -1) { |
3c0ef626 | 931 | switch (opt) { |
932 | case '4': | |
dfddba3d | 933 | options.address_family = AF_INET; |
3c0ef626 | 934 | break; |
935 | case '6': | |
dfddba3d | 936 | options.address_family = AF_INET6; |
3c0ef626 | 937 | break; |
938 | case 'f': | |
939 | config_file_name = optarg; | |
940 | break; | |
941 | case 'd': | |
7cac2b65 | 942 | if (debug_flag == 0) { |
3c0ef626 | 943 | debug_flag = 1; |
944 | options.log_level = SYSLOG_LEVEL_DEBUG1; | |
7cac2b65 | 945 | } else if (options.log_level < SYSLOG_LEVEL_DEBUG3) |
3c0ef626 | 946 | options.log_level++; |
3c0ef626 | 947 | break; |
948 | case 'D': | |
949 | no_daemon_flag = 1; | |
950 | break; | |
951 | case 'e': | |
952 | log_stderr = 1; | |
953 | break; | |
954 | case 'i': | |
955 | inetd_flag = 1; | |
956 | break; | |
7e82606e | 957 | case 'r': |
958 | rexec_flag = 0; | |
959 | break; | |
960 | case 'R': | |
961 | rexeced_flag = 1; | |
962 | inetd_flag = 1; | |
963 | break; | |
3c0ef626 | 964 | case 'Q': |
965 | /* ignored */ | |
966 | break; | |
967 | case 'q': | |
968 | options.log_level = SYSLOG_LEVEL_QUIET; | |
969 | break; | |
970 | case 'b': | |
971 | options.server_key_bits = atoi(optarg); | |
972 | break; | |
973 | case 'p': | |
974 | options.ports_from_cmdline = 1; | |
975 | if (options.num_ports >= MAX_PORTS) { | |
976 | fprintf(stderr, "too many ports.\n"); | |
977 | exit(1); | |
978 | } | |
979 | options.ports[options.num_ports++] = a2port(optarg); | |
980 | if (options.ports[options.num_ports-1] == 0) { | |
981 | fprintf(stderr, "Bad port number.\n"); | |
982 | exit(1); | |
983 | } | |
984 | break; | |
985 | case 'g': | |
986 | if ((options.login_grace_time = convtime(optarg)) == -1) { | |
987 | fprintf(stderr, "Invalid login grace time.\n"); | |
988 | exit(1); | |
989 | } | |
990 | break; | |
991 | case 'k': | |
992 | if ((options.key_regeneration_time = convtime(optarg)) == -1) { | |
993 | fprintf(stderr, "Invalid key regeneration interval.\n"); | |
994 | exit(1); | |
995 | } | |
996 | break; | |
997 | case 'h': | |
998 | if (options.num_host_key_files >= MAX_HOSTKEYS) { | |
999 | fprintf(stderr, "too many host keys.\n"); | |
1000 | exit(1); | |
1001 | } | |
1002 | options.host_key_files[options.num_host_key_files++] = optarg; | |
1003 | break; | |
3c0ef626 | 1004 | case 't': |
1005 | test_flag = 1; | |
1006 | break; | |
1007 | case 'u': | |
1008 | utmp_len = atoi(optarg); | |
d03f4262 | 1009 | if (utmp_len > MAXHOSTNAMELEN) { |
1010 | fprintf(stderr, "Invalid utmp length.\n"); | |
1011 | exit(1); | |
1012 | } | |
3c0ef626 | 1013 | break; |
1e608e42 | 1014 | case 'o': |
540d72c3 | 1015 | line = xstrdup(optarg); |
1016 | if (process_server_config_line(&options, line, | |
1e608e42 | 1017 | "command-line", 0) != 0) |
1018 | exit(1); | |
540d72c3 | 1019 | xfree(line); |
1e608e42 | 1020 | break; |
3c0ef626 | 1021 | case '?': |
1022 | default: | |
1e608e42 | 1023 | usage(); |
1024 | break; | |
3c0ef626 | 1025 | } |
1026 | } | |
7e82606e | 1027 | if (rexeced_flag || inetd_flag) |
1028 | rexec_flag = 0; | |
1029 | if (rexec_flag && (av[0] == NULL || *av[0] != '/')) | |
1030 | fatal("sshd re-exec requires execution with an absolute path"); | |
1031 | if (rexeced_flag) | |
1032 | closefrom(REEXEC_MIN_FREE_FD); | |
1033 | else | |
1034 | closefrom(REEXEC_DEVCRYPTO_RESERVED_FD); | |
1035 | ||
3c0ef626 | 1036 | SSLeay_add_all_algorithms(); |
3c0ef626 | 1037 | |
1038 | /* | |
1039 | * Force logging to stderr until we have loaded the private host | |
1040 | * key (unless started from inetd) | |
1041 | */ | |
1042 | log_init(__progname, | |
1e608e42 | 1043 | options.log_level == SYSLOG_LEVEL_NOT_SET ? |
1044 | SYSLOG_LEVEL_INFO : options.log_level, | |
1045 | options.log_facility == SYSLOG_FACILITY_NOT_SET ? | |
1046 | SYSLOG_FACILITY_AUTH : options.log_facility, | |
bfe49944 | 1047 | log_stderr || !inetd_flag); |
3c0ef626 | 1048 | |
12a403af | 1049 | /* |
1050 | * Unset KRB5CCNAME, otherwise the user's session may inherit it from | |
1051 | * root's environment | |
2ce0bfe4 | 1052 | */ |
dfddba3d | 1053 | if (getenv("KRB5CCNAME") != NULL) |
1054 | unsetenv("KRB5CCNAME"); | |
1055 | ||
d03f4262 | 1056 | #ifdef _UNICOS |
7e82606e | 1057 | /* Cray can define user privs drop all privs now! |
3c0ef626 | 1058 | * Not needed on PRIV_SU systems! |
1059 | */ | |
1060 | drop_cray_privs(); | |
1061 | #endif | |
1062 | ||
1063 | seed_rng(); | |
1064 | ||
7e82606e | 1065 | sensitive_data.server_key = NULL; |
1066 | sensitive_data.ssh1_host_key = NULL; | |
1067 | sensitive_data.have_ssh1_key = 0; | |
1068 | sensitive_data.have_ssh2_key = 0; | |
1069 | ||
1070 | /* Fetch our configuration */ | |
1071 | buffer_init(&cfg); | |
1072 | if (rexeced_flag) | |
1073 | recv_rexec_state(REEXEC_CONFIG_PASS_FD, &cfg); | |
1074 | else | |
1075 | load_server_config(config_file_name, &cfg); | |
1076 | ||
1077 | parse_server_config(&options, | |
1078 | rexeced_flag ? "rexec" : config_file_name, &cfg); | |
1079 | ||
1080 | if (!rexec_flag) | |
1081 | buffer_free(&cfg); | |
3c0ef626 | 1082 | |
1083 | /* Fill in default values for those options not explicitly set. */ | |
1084 | fill_default_server_options(&options); | |
1085 | ||
dfddba3d | 1086 | /* set default channel AF */ |
1087 | channel_set_af(options.address_family); | |
1088 | ||
3c0ef626 | 1089 | /* Check that there are no remaining arguments. */ |
1090 | if (optind < ac) { | |
1091 | fprintf(stderr, "Extra argument %s.\n", av[optind]); | |
1092 | exit(1); | |
1093 | } | |
1094 | ||
dfddba3d | 1095 | debug("sshd version %.100s", SSH_RELEASE); |
3c0ef626 | 1096 | |
1097 | /* load private host keys */ | |
d03f4262 | 1098 | sensitive_data.host_keys = xmalloc(options.num_host_key_files * |
1099 | sizeof(Key *)); | |
1e608e42 | 1100 | for (i = 0; i < options.num_host_key_files; i++) |
3c0ef626 | 1101 | sensitive_data.host_keys[i] = NULL; |
3c0ef626 | 1102 | |
1e608e42 | 1103 | for (i = 0; i < options.num_host_key_files; i++) { |
3c0ef626 | 1104 | key = key_load_private(options.host_key_files[i], "", NULL); |
1105 | sensitive_data.host_keys[i] = key; | |
1106 | if (key == NULL) { | |
1107 | error("Could not load host key: %s", | |
1108 | options.host_key_files[i]); | |
1109 | sensitive_data.host_keys[i] = NULL; | |
1110 | continue; | |
1111 | } | |
1e608e42 | 1112 | switch (key->type) { |
3c0ef626 | 1113 | case KEY_RSA1: |
1114 | sensitive_data.ssh1_host_key = key; | |
1115 | sensitive_data.have_ssh1_key = 1; | |
1116 | break; | |
1117 | case KEY_RSA: | |
1118 | case KEY_DSA: | |
1119 | sensitive_data.have_ssh2_key = 1; | |
1120 | break; | |
1121 | } | |
1122 | debug("private host key: #%d type %d %s", i, key->type, | |
1123 | key_type(key)); | |
1124 | } | |
1125 | if ((options.protocol & SSH_PROTO_1) && !sensitive_data.have_ssh1_key) { | |
7cac2b65 | 1126 | logit("Disabling protocol version 1. Could not load host key"); |
3c0ef626 | 1127 | options.protocol &= ~SSH_PROTO_1; |
1128 | } | |
5598e598 | 1129 | #ifndef GSSAPI |
1130 | /* The GSSAPI key exchange can run without a host key */ | |
3c0ef626 | 1131 | if ((options.protocol & SSH_PROTO_2) && !sensitive_data.have_ssh2_key) { |
7cac2b65 | 1132 | logit("Disabling protocol version 2. Could not load host key"); |
3c0ef626 | 1133 | options.protocol &= ~SSH_PROTO_2; |
1134 | } | |
5598e598 | 1135 | #endif |
3c0ef626 | 1136 | if (!(options.protocol & (SSH_PROTO_1|SSH_PROTO_2))) { |
7cac2b65 | 1137 | logit("sshd: no hostkeys available -- exiting."); |
3c0ef626 | 1138 | exit(1); |
1139 | } | |
1140 | ||
1141 | /* Check certain values for sanity. */ | |
1142 | if (options.protocol & SSH_PROTO_1) { | |
1143 | if (options.server_key_bits < 512 || | |
1144 | options.server_key_bits > 32768) { | |
1145 | fprintf(stderr, "Bad server key size.\n"); | |
1146 | exit(1); | |
1147 | } | |
1148 | /* | |
1149 | * Check that server and host key lengths differ sufficiently. This | |
1150 | * is necessary to make double encryption work with rsaref. Oh, I | |
1151 | * hate software patents. I dont know if this can go? Niels | |
1152 | */ | |
1153 | if (options.server_key_bits > | |
276b07a3 | 1154 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) - |
1155 | SSH_KEY_BITS_RESERVED && options.server_key_bits < | |
1156 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + | |
1157 | SSH_KEY_BITS_RESERVED) { | |
3c0ef626 | 1158 | options.server_key_bits = |
276b07a3 | 1159 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + |
1160 | SSH_KEY_BITS_RESERVED; | |
3c0ef626 | 1161 | debug("Forcing server key to %d bits to make it differ from host key.", |
1162 | options.server_key_bits); | |
1163 | } | |
1164 | } | |
1165 | ||
44a053a3 | 1166 | if (use_privsep) { |
1167 | struct passwd *pw; | |
1168 | struct stat st; | |
1169 | ||
1170 | if ((pw = getpwnam(SSH_PRIVSEP_USER)) == NULL) | |
1171 | fatal("Privilege separation user %s does not exist", | |
1172 | SSH_PRIVSEP_USER); | |
1173 | if ((stat(_PATH_PRIVSEP_CHROOT_DIR, &st) == -1) || | |
1174 | (S_ISDIR(st.st_mode) == 0)) | |
1175 | fatal("Missing privilege separation directory: %s", | |
1176 | _PATH_PRIVSEP_CHROOT_DIR); | |
d03f4262 | 1177 | |
1178 | #ifdef HAVE_CYGWIN | |
1179 | if (check_ntsec(_PATH_PRIVSEP_CHROOT_DIR) && | |
1180 | (st.st_uid != getuid () || | |
1181 | (st.st_mode & (S_IWGRP|S_IWOTH)) != 0)) | |
1182 | #else | |
276b07a3 | 1183 | if (st.st_uid != 0 || (st.st_mode & (S_IWGRP|S_IWOTH)) != 0) |
d03f4262 | 1184 | #endif |
bfe49944 | 1185 | fatal("%s must be owned by root and not group or " |
1186 | "world-writable.", _PATH_PRIVSEP_CHROOT_DIR); | |
44a053a3 | 1187 | } |
1188 | ||
3c0ef626 | 1189 | /* Configuration looks good, so exit if in test mode. */ |
1190 | if (test_flag) | |
1191 | exit(0); | |
1192 | ||
510132b6 | 1193 | /* |
1194 | * Clear out any supplemental groups we may have inherited. This | |
1195 | * prevents inadvertent creation of files with bad modes (in the | |
540d72c3 | 1196 | * portable version at least, it's certainly possible for PAM |
1197 | * to create a file, and we can't control the code in every | |
510132b6 | 1198 | * module which might be used). |
1199 | */ | |
1200 | if (setgroups(0, NULL) < 0) | |
1201 | debug("setgroups() failed: %.200s", strerror(errno)); | |
3c0ef626 | 1202 | |
7e82606e | 1203 | if (rexec_flag) { |
1204 | rexec_argv = xmalloc(sizeof(char *) * (rexec_argc + 2)); | |
1205 | for (i = 0; i < rexec_argc; i++) { | |
1206 | debug("rexec_argv[%d]='%s'", i, saved_argv[i]); | |
1207 | rexec_argv[i] = saved_argv[i]; | |
1208 | } | |
1209 | rexec_argv[rexec_argc] = "-R"; | |
1210 | rexec_argv[rexec_argc + 1] = NULL; | |
1211 | } | |
1212 | ||
3c0ef626 | 1213 | /* Initialize the log (it is reinitialized below in case we forked). */ |
dfddba3d | 1214 | if (debug_flag && (!inetd_flag || rexeced_flag)) |
3c0ef626 | 1215 | log_stderr = 1; |
1216 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
1217 | ||
1218 | /* | |
1219 | * If not in debugging mode, and not started from inetd, disconnect | |
1220 | * from the controlling terminal, and fork. The original process | |
1221 | * exits. | |
1222 | */ | |
1223 | if (!(debug_flag || inetd_flag || no_daemon_flag)) { | |
1224 | #ifdef TIOCNOTTY | |
1225 | int fd; | |
1226 | #endif /* TIOCNOTTY */ | |
1227 | if (daemon(0, 0) < 0) | |
1228 | fatal("daemon() failed: %.200s", strerror(errno)); | |
1229 | ||
1230 | /* Disconnect from the controlling tty. */ | |
1231 | #ifdef TIOCNOTTY | |
1232 | fd = open(_PATH_TTY, O_RDWR | O_NOCTTY); | |
1233 | if (fd >= 0) { | |
1234 | (void) ioctl(fd, TIOCNOTTY, NULL); | |
1235 | close(fd); | |
1236 | } | |
1237 | #endif /* TIOCNOTTY */ | |
1238 | } | |
1239 | /* Reinitialize the log (because of the fork above). */ | |
1240 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
1241 | ||
1242 | /* Initialize the random number generator. */ | |
1243 | arc4random_stir(); | |
1244 | ||
1245 | /* Chdir to the root directory so that the current disk can be | |
1246 | unmounted if desired. */ | |
1247 | chdir("/"); | |
1e608e42 | 1248 | |
3c0ef626 | 1249 | /* ignore SIGPIPE */ |
1250 | signal(SIGPIPE, SIG_IGN); | |
1251 | ||
1252 | /* Start listening for a socket, unless started from inetd. */ | |
1253 | if (inetd_flag) { | |
7e82606e | 1254 | int fd; |
1255 | ||
3c0ef626 | 1256 | startup_pipe = -1; |
7e82606e | 1257 | if (rexeced_flag) { |
1258 | close(REEXEC_CONFIG_PASS_FD); | |
1259 | sock_in = sock_out = dup(STDIN_FILENO); | |
1260 | if (!debug_flag) { | |
1261 | startup_pipe = dup(REEXEC_STARTUP_PIPE_FD); | |
1262 | close(REEXEC_STARTUP_PIPE_FD); | |
1263 | } | |
1264 | } else { | |
1265 | sock_in = dup(STDIN_FILENO); | |
1266 | sock_out = dup(STDOUT_FILENO); | |
1267 | } | |
3c0ef626 | 1268 | /* |
1269 | * We intentionally do not close the descriptors 0, 1, and 2 | |
7e82606e | 1270 | * as our code for setting the descriptors won't work if |
3c0ef626 | 1271 | * ttyfd happens to be one of those. |
1272 | */ | |
7e82606e | 1273 | if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { |
1274 | dup2(fd, STDIN_FILENO); | |
1275 | dup2(fd, STDOUT_FILENO); | |
1276 | if (fd > STDOUT_FILENO) | |
1277 | close(fd); | |
1278 | } | |
3c0ef626 | 1279 | debug("inetd sockets after dupping: %d, %d", sock_in, sock_out); |
7e82606e | 1280 | if ((options.protocol & SSH_PROTO_1) && |
1281 | sensitive_data.server_key == NULL) | |
3c0ef626 | 1282 | generate_ephemeral_server_key(); |
1283 | } else { | |
1284 | for (ai = options.listen_addrs; ai; ai = ai->ai_next) { | |
1285 | if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6) | |
1286 | continue; | |
1287 | if (num_listen_socks >= MAX_LISTEN_SOCKS) | |
1288 | fatal("Too many listen sockets. " | |
1289 | "Enlarge MAX_LISTEN_SOCKS"); | |
dfddba3d | 1290 | if ((ret = getnameinfo(ai->ai_addr, ai->ai_addrlen, |
3c0ef626 | 1291 | ntop, sizeof(ntop), strport, sizeof(strport), |
dfddba3d | 1292 | NI_NUMERICHOST|NI_NUMERICSERV)) != 0) { |
1293 | error("getnameinfo failed: %.100s", | |
1294 | (ret != EAI_SYSTEM) ? gai_strerror(ret) : | |
1295 | strerror(errno)); | |
3c0ef626 | 1296 | continue; |
1297 | } | |
1298 | /* Create socket for listening. */ | |
7cac2b65 | 1299 | listen_sock = socket(ai->ai_family, ai->ai_socktype, |
1300 | ai->ai_protocol); | |
3c0ef626 | 1301 | if (listen_sock < 0) { |
1302 | /* kernel may not support ipv6 */ | |
1303 | verbose("socket: %.100s", strerror(errno)); | |
1304 | continue; | |
1305 | } | |
7e82606e | 1306 | if (set_nonblock(listen_sock) == -1) { |
3c0ef626 | 1307 | close(listen_sock); |
1308 | continue; | |
1309 | } | |
1310 | /* | |
d03f4262 | 1311 | * Set socket options. |
1312 | * Allow local port reuse in TIME_WAIT. | |
3c0ef626 | 1313 | */ |
d03f4262 | 1314 | if (setsockopt(listen_sock, SOL_SOCKET, SO_REUSEADDR, |
1315 | &on, sizeof(on)) == -1) | |
1316 | error("setsockopt SO_REUSEADDR: %s", strerror(errno)); | |
3c0ef626 | 1317 | |
1318 | debug("Bind to port %s on %s.", strport, ntop); | |
1319 | ||
1320 | /* Bind the socket to the desired port. */ | |
1321 | if (bind(listen_sock, ai->ai_addr, ai->ai_addrlen) < 0) { | |
1322 | if (!ai->ai_next) | |
1323 | error("Bind to port %s on %s failed: %.200s.", | |
1324 | strport, ntop, strerror(errno)); | |
1325 | close(listen_sock); | |
1326 | continue; | |
1327 | } | |
1328 | listen_socks[num_listen_socks] = listen_sock; | |
1329 | num_listen_socks++; | |
1330 | ||
1331 | /* Start listening on the port. */ | |
7cac2b65 | 1332 | logit("Server listening on %s port %s.", ntop, strport); |
540d72c3 | 1333 | if (listen(listen_sock, SSH_LISTEN_BACKLOG) < 0) |
3c0ef626 | 1334 | fatal("listen: %.100s", strerror(errno)); |
1335 | ||
1336 | } | |
1337 | freeaddrinfo(options.listen_addrs); | |
1338 | ||
1339 | if (!num_listen_socks) | |
1340 | fatal("Cannot bind any address."); | |
1341 | ||
1342 | if (options.protocol & SSH_PROTO_1) | |
1343 | generate_ephemeral_server_key(); | |
1344 | ||
1345 | /* | |
1346 | * Arrange to restart on SIGHUP. The handler needs | |
1347 | * listen_sock. | |
1348 | */ | |
1349 | signal(SIGHUP, sighup_handler); | |
1350 | ||
1351 | signal(SIGTERM, sigterm_handler); | |
1352 | signal(SIGQUIT, sigterm_handler); | |
1353 | ||
1354 | /* Arrange SIGCHLD to be caught. */ | |
1355 | signal(SIGCHLD, main_sigchld_handler); | |
1356 | ||
1357 | /* Write out the pid file after the sigterm handler is setup */ | |
1358 | if (!debug_flag) { | |
1359 | /* | |
1360 | * Record our pid in /var/run/sshd.pid to make it | |
1361 | * easier to kill the correct sshd. We don't want to | |
1362 | * do this before the bind above because the bind will | |
1363 | * fail if there already is a daemon, and this will | |
1364 | * overwrite any old pid in the file. | |
1365 | */ | |
1366 | f = fopen(options.pid_file, "wb"); | |
7cac2b65 | 1367 | if (f == NULL) { |
1368 | error("Couldn't create pid file \"%s\": %s", | |
1369 | options.pid_file, strerror(errno)); | |
1370 | } else { | |
44a053a3 | 1371 | fprintf(f, "%ld\n", (long) getpid()); |
3c0ef626 | 1372 | fclose(f); |
1373 | } | |
1374 | } | |
1375 | ||
1376 | /* setup fd set for listen */ | |
1377 | fdset = NULL; | |
1378 | maxfd = 0; | |
1379 | for (i = 0; i < num_listen_socks; i++) | |
1380 | if (listen_socks[i] > maxfd) | |
1381 | maxfd = listen_socks[i]; | |
1382 | /* pipes connected to unauthenticated childs */ | |
1383 | startup_pipes = xmalloc(options.max_startups * sizeof(int)); | |
1384 | for (i = 0; i < options.max_startups; i++) | |
1385 | startup_pipes[i] = -1; | |
1386 | ||
1387 | /* | |
1388 | * Stay listening for connections until the system crashes or | |
1389 | * the daemon is killed with a signal. | |
1390 | */ | |
1391 | for (;;) { | |
1392 | if (received_sighup) | |
1393 | sighup_restart(); | |
1394 | if (fdset != NULL) | |
1395 | xfree(fdset); | |
1396 | fdsetsz = howmany(maxfd+1, NFDBITS) * sizeof(fd_mask); | |
1397 | fdset = (fd_set *)xmalloc(fdsetsz); | |
1398 | memset(fdset, 0, fdsetsz); | |
1399 | ||
1400 | for (i = 0; i < num_listen_socks; i++) | |
1401 | FD_SET(listen_socks[i], fdset); | |
1402 | for (i = 0; i < options.max_startups; i++) | |
1403 | if (startup_pipes[i] != -1) | |
1404 | FD_SET(startup_pipes[i], fdset); | |
1405 | ||
1406 | /* Wait in select until there is a connection. */ | |
1407 | ret = select(maxfd+1, fdset, NULL, NULL, NULL); | |
1408 | if (ret < 0 && errno != EINTR) | |
1409 | error("select: %.100s", strerror(errno)); | |
1410 | if (received_sigterm) { | |
7cac2b65 | 1411 | logit("Received signal %d; terminating.", |
1e608e42 | 1412 | (int) received_sigterm); |
3c0ef626 | 1413 | close_listen_socks(); |
1414 | unlink(options.pid_file); | |
1415 | exit(255); | |
1416 | } | |
1417 | if (key_used && key_do_regen) { | |
1418 | generate_ephemeral_server_key(); | |
1419 | key_used = 0; | |
1420 | key_do_regen = 0; | |
1421 | } | |
1422 | if (ret < 0) | |
1423 | continue; | |
1424 | ||
1425 | for (i = 0; i < options.max_startups; i++) | |
1426 | if (startup_pipes[i] != -1 && | |
1427 | FD_ISSET(startup_pipes[i], fdset)) { | |
1428 | /* | |
1429 | * the read end of the pipe is ready | |
1430 | * if the child has closed the pipe | |
1431 | * after successful authentication | |
1432 | * or if the child has died | |
1433 | */ | |
1434 | close(startup_pipes[i]); | |
1435 | startup_pipes[i] = -1; | |
1436 | startups--; | |
1437 | } | |
1438 | for (i = 0; i < num_listen_socks; i++) { | |
1439 | if (!FD_ISSET(listen_socks[i], fdset)) | |
1440 | continue; | |
1441 | fromlen = sizeof(from); | |
1442 | newsock = accept(listen_socks[i], (struct sockaddr *)&from, | |
1443 | &fromlen); | |
1444 | if (newsock < 0) { | |
1445 | if (errno != EINTR && errno != EWOULDBLOCK) | |
1446 | error("accept: %.100s", strerror(errno)); | |
1447 | continue; | |
1448 | } | |
7e82606e | 1449 | if (unset_nonblock(newsock) == -1) { |
1e608e42 | 1450 | close(newsock); |
3c0ef626 | 1451 | continue; |
1452 | } | |
1453 | if (drop_connection(startups) == 1) { | |
1454 | debug("drop connection #%d", startups); | |
1455 | close(newsock); | |
1456 | continue; | |
1457 | } | |
1458 | if (pipe(startup_p) == -1) { | |
1459 | close(newsock); | |
1460 | continue; | |
1461 | } | |
1462 | ||
7e82606e | 1463 | if (rexec_flag && socketpair(AF_UNIX, |
1464 | SOCK_STREAM, 0, config_s) == -1) { | |
1465 | error("reexec socketpair: %s", | |
1466 | strerror(errno)); | |
1467 | close(newsock); | |
1468 | close(startup_p[0]); | |
1469 | close(startup_p[1]); | |
1470 | continue; | |
1471 | } | |
1472 | ||
3c0ef626 | 1473 | for (j = 0; j < options.max_startups; j++) |
1474 | if (startup_pipes[j] == -1) { | |
1475 | startup_pipes[j] = startup_p[0]; | |
1476 | if (maxfd < startup_p[0]) | |
1477 | maxfd = startup_p[0]; | |
1478 | startups++; | |
1479 | break; | |
1480 | } | |
1481 | ||
1482 | /* | |
1483 | * Got connection. Fork a child to handle it, unless | |
1484 | * we are in debugging mode. | |
1485 | */ | |
1486 | if (debug_flag) { | |
1487 | /* | |
1488 | * In debugging mode. Close the listening | |
1489 | * socket, and start processing the | |
1490 | * connection without forking. | |
1491 | */ | |
1492 | debug("Server will not fork when running in debugging mode."); | |
1493 | close_listen_socks(); | |
1494 | sock_in = newsock; | |
1495 | sock_out = newsock; | |
7e82606e | 1496 | close(startup_p[0]); |
1497 | close(startup_p[1]); | |
3c0ef626 | 1498 | startup_pipe = -1; |
1499 | pid = getpid(); | |
7e82606e | 1500 | if (rexec_flag) { |
1501 | send_rexec_state(config_s[0], | |
1502 | &cfg); | |
1503 | close(config_s[0]); | |
1504 | } | |
3c0ef626 | 1505 | break; |
1506 | } else { | |
1507 | /* | |
1508 | * Normal production daemon. Fork, and have | |
1509 | * the child process the connection. The | |
1510 | * parent continues listening. | |
1511 | */ | |
1512 | if ((pid = fork()) == 0) { | |
1513 | /* | |
1514 | * Child. Close the listening and max_startup | |
1515 | * sockets. Start using the accepted socket. | |
1516 | * Reinitialize logging (since our pid has | |
1517 | * changed). We break out of the loop to handle | |
1518 | * the connection. | |
1519 | */ | |
1520 | startup_pipe = startup_p[1]; | |
1e608e42 | 1521 | close_startup_pipes(); |
3c0ef626 | 1522 | close_listen_socks(); |
1523 | sock_in = newsock; | |
1524 | sock_out = newsock; | |
1525 | log_init(__progname, options.log_level, options.log_facility, log_stderr); | |
dfddba3d | 1526 | if (rexec_flag) |
1527 | close(config_s[0]); | |
3c0ef626 | 1528 | break; |
1529 | } | |
1530 | } | |
1531 | ||
1532 | /* Parent. Stay in the loop. */ | |
1533 | if (pid < 0) | |
1534 | error("fork: %.100s", strerror(errno)); | |
1535 | else | |
44a053a3 | 1536 | debug("Forked child %ld.", (long)pid); |
3c0ef626 | 1537 | |
1538 | close(startup_p[1]); | |
1539 | ||
7e82606e | 1540 | if (rexec_flag) { |
1541 | send_rexec_state(config_s[0], &cfg); | |
1542 | close(config_s[0]); | |
1543 | close(config_s[1]); | |
1544 | } | |
1545 | ||
3c0ef626 | 1546 | /* Mark that the key has been used (it was "given" to the child). */ |
1547 | if ((options.protocol & SSH_PROTO_1) && | |
1548 | key_used == 0) { | |
1549 | /* Schedule server key regeneration alarm. */ | |
1550 | signal(SIGALRM, key_regeneration_alarm); | |
1551 | alarm(options.key_regeneration_time); | |
1552 | key_used = 1; | |
1553 | } | |
1554 | ||
1555 | arc4random_stir(); | |
1556 | ||
1557 | /* Close the new socket (the child is now taking care of it). */ | |
1558 | close(newsock); | |
1559 | } | |
1560 | /* child process check (or debug mode) */ | |
1561 | if (num_listen_socks < 0) | |
1562 | break; | |
1563 | } | |
1564 | } | |
1565 | ||
1566 | /* This is the child processing a new connection. */ | |
12a403af | 1567 | setproctitle("%s", "[accepted]"); |
3c0ef626 | 1568 | |
510132b6 | 1569 | /* |
1570 | * Create a new session and process group since the 4.4BSD | |
1571 | * setlogin() affects the entire process group. We don't | |
1572 | * want the child to be able to affect the parent. | |
1573 | */ | |
7cac2b65 | 1574 | #if !defined(SSHD_ACQUIRES_CTTY) |
bfe49944 | 1575 | /* |
7cac2b65 | 1576 | * If setsid is called, on some platforms sshd will later acquire a |
1577 | * controlling terminal which will result in "could not set | |
1578 | * controlling tty" errors. | |
bfe49944 | 1579 | */ |
276b07a3 | 1580 | if (!debug_flag && !inetd_flag && setsid() < 0) |
510132b6 | 1581 | error("setsid: %.100s", strerror(errno)); |
1582 | #endif | |
1583 | ||
7e82606e | 1584 | if (rexec_flag) { |
1585 | int fd; | |
1586 | ||
1587 | debug("rexec start in %d out %d newsock %d pipe %d sock %d", | |
1588 | sock_in, sock_out, newsock, startup_pipe, config_s[0]); | |
1589 | dup2(newsock, STDIN_FILENO); | |
1590 | dup2(STDIN_FILENO, STDOUT_FILENO); | |
1591 | if (startup_pipe == -1) | |
1592 | close(REEXEC_STARTUP_PIPE_FD); | |
1593 | else | |
1594 | dup2(startup_pipe, REEXEC_STARTUP_PIPE_FD); | |
1595 | ||
1596 | dup2(config_s[1], REEXEC_CONFIG_PASS_FD); | |
1597 | close(config_s[1]); | |
1598 | if (startup_pipe != -1) | |
1599 | close(startup_pipe); | |
1600 | ||
1601 | execv(rexec_argv[0], rexec_argv); | |
1602 | ||
1603 | /* Reexec has failed, fall back and continue */ | |
1604 | error("rexec of %s failed: %s", rexec_argv[0], strerror(errno)); | |
1605 | recv_rexec_state(REEXEC_CONFIG_PASS_FD, NULL); | |
1606 | log_init(__progname, options.log_level, | |
1607 | options.log_facility, log_stderr); | |
1608 | ||
1609 | /* Clean up fds */ | |
1610 | startup_pipe = REEXEC_STARTUP_PIPE_FD; | |
1611 | close(config_s[1]); | |
1612 | close(REEXEC_CONFIG_PASS_FD); | |
1613 | newsock = sock_out = sock_in = dup(STDIN_FILENO); | |
1614 | if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { | |
1615 | dup2(fd, STDIN_FILENO); | |
1616 | dup2(fd, STDOUT_FILENO); | |
1617 | if (fd > STDERR_FILENO) | |
1618 | close(fd); | |
1619 | } | |
1620 | debug("rexec cleanup in %d out %d newsock %d pipe %d sock %d", | |
1621 | sock_in, sock_out, newsock, startup_pipe, config_s[0]); | |
1622 | } | |
1623 | ||
3c0ef626 | 1624 | /* |
1625 | * Disable the key regeneration alarm. We will not regenerate the | |
1626 | * key since we are no longer in a position to give it to anyone. We | |
1627 | * will not restart on SIGHUP since it no longer makes sense. | |
1628 | */ | |
1629 | alarm(0); | |
1630 | signal(SIGALRM, SIG_DFL); | |
1631 | signal(SIGHUP, SIG_DFL); | |
1632 | signal(SIGTERM, SIG_DFL); | |
1633 | signal(SIGQUIT, SIG_DFL); | |
1634 | signal(SIGCHLD, SIG_DFL); | |
1635 | signal(SIGINT, SIG_DFL); | |
1636 | ||
3c0ef626 | 1637 | /* |
1638 | * Register our connection. This turns encryption off because we do | |
1639 | * not have a key. | |
1640 | */ | |
1641 | packet_set_connection(sock_in, sock_out); | |
2ce0bfe4 | 1642 | packet_set_server(); |
3c0ef626 | 1643 | |
2ce0bfe4 | 1644 | /* Set SO_KEEPALIVE if requested. */ |
1645 | if (options.tcp_keep_alive && packet_connection_is_on_socket() && | |
1646 | setsockopt(sock_in, SOL_SOCKET, SO_KEEPALIVE, &on, sizeof(on)) < 0) | |
1647 | error("setsockopt SO_KEEPALIVE: %.100s", strerror(errno)); | |
1648 | ||
1649 | if ((remote_port = get_remote_port()) < 0) { | |
1650 | debug("get_remote_port failed"); | |
1651 | cleanup_exit(255); | |
1652 | } | |
3c0ef626 | 1653 | remote_ip = get_remote_ipaddr(); |
1654 | ||
dfddba3d | 1655 | #ifdef SSH_AUDIT_EVENTS |
1656 | audit_connection_from(remote_ip, remote_port); | |
1657 | #endif | |
3c0ef626 | 1658 | #ifdef LIBWRAP |
1659 | /* Check whether logins are denied from this host. */ | |
7e82606e | 1660 | if (packet_connection_is_on_socket()) { |
3c0ef626 | 1661 | struct request_info req; |
1662 | ||
1663 | request_init(&req, RQ_DAEMON, __progname, RQ_FILE, sock_in, 0); | |
1664 | fromhost(&req); | |
1665 | ||
1666 | if (!hosts_access(&req)) { | |
1667 | debug("Connection refused by tcp wrapper"); | |
1668 | refuse(&req); | |
1669 | /* NOTREACHED */ | |
1670 | fatal("libwrap refuse returns"); | |
1671 | } | |
1672 | } | |
1673 | #endif /* LIBWRAP */ | |
1674 | ||
1675 | /* Log the connection. */ | |
1676 | verbose("Connection from %.500s port %d", remote_ip, remote_port); | |
1677 | ||
1678 | /* | |
1679 | * We don\'t want to listen forever unless the other side | |
1680 | * successfully authenticates itself. So we set up an alarm which is | |
1681 | * cleared after successful authentication. A limit of zero | |
1682 | * indicates no limit. Note that we don\'t set the alarm in debugging | |
1683 | * mode; it is just annoying to have the server exit just when you | |
1684 | * are about to discover the bug. | |
1685 | */ | |
1686 | signal(SIGALRM, grace_alarm_handler); | |
1687 | if (!debug_flag) | |
1688 | alarm(options.login_grace_time); | |
1689 | ||
1690 | sshd_exchange_identification(sock_in, sock_out); | |
7cac2b65 | 1691 | #if defined(AFS_KRB5) |
3c0ef626 | 1692 | /* If machine has AFS, set process authentication group. */ |
1693 | if (k_hasafs()) { | |
1694 | k_setpag(); | |
1695 | k_unlog(); | |
1696 | } | |
62eb343a | 1697 | #endif /* AFS || AFS_KRB5 */ |
3c0ef626 | 1698 | |
1699 | packet_set_nonblocking(); | |
1700 | ||
540d72c3 | 1701 | /* allocate authentication context */ |
1702 | authctxt = xmalloc(sizeof(*authctxt)); | |
1703 | memset(authctxt, 0, sizeof(*authctxt)); | |
1704 | ||
8b32eddc | 1705 | authctxt->loginmsg = &loginmsg; |
1706 | ||
540d72c3 | 1707 | /* XXX global for cleanup, access from other modules */ |
1708 | the_authctxt = authctxt; | |
1709 | ||
dfddba3d | 1710 | /* prepare buffer to collect messages to display to user after login */ |
1711 | buffer_init(&loginmsg); | |
1712 | ||
510132b6 | 1713 | if (use_privsep) |
540d72c3 | 1714 | if (privsep_preauth(authctxt) == 1) |
510132b6 | 1715 | goto authenticated; |
1716 | ||
3c0ef626 | 1717 | /* perform the key exchange */ |
1718 | /* authenticate user and start session */ | |
1719 | if (compat20) { | |
1720 | do_ssh2_kex(); | |
540d72c3 | 1721 | do_authentication2(authctxt); |
3c0ef626 | 1722 | } else { |
1723 | do_ssh1_kex(); | |
540d72c3 | 1724 | do_authentication(authctxt); |
510132b6 | 1725 | } |
1726 | /* | |
1727 | * If we use privilege separation, the unprivileged child transfers | |
1728 | * the current keystate and exits | |
1729 | */ | |
1730 | if (use_privsep) { | |
1731 | mm_send_keystate(pmonitor); | |
1732 | exit(0); | |
3c0ef626 | 1733 | } |
510132b6 | 1734 | |
1735 | authenticated: | |
dfddba3d | 1736 | #ifdef SSH_AUDIT_EVENTS |
1737 | audit_event(SSH_AUTH_SUCCESS); | |
1738 | #endif | |
1739 | ||
510132b6 | 1740 | /* |
1741 | * In privilege separation, we fork another child and prepare | |
1742 | * file descriptor passing. | |
1743 | */ | |
1744 | if (use_privsep) { | |
1745 | privsep_postauth(authctxt); | |
1746 | /* the monitor process [priv] will not return */ | |
1747 | if (!compat20) | |
1748 | destroy_sensitive_data(); | |
1749 | } | |
1750 | ||
540d72c3 | 1751 | /* Start session. */ |
510132b6 | 1752 | do_authenticated(authctxt); |
1753 | ||
3c0ef626 | 1754 | /* The connection has been terminated. */ |
1755 | verbose("Closing connection to %.100s", remote_ip); | |
1756 | ||
1757 | #ifdef USE_PAM | |
7cac2b65 | 1758 | if (options.use_pam) |
1759 | finish_pam(); | |
3c0ef626 | 1760 | #endif /* USE_PAM */ |
1761 | ||
dfddba3d | 1762 | #ifdef SSH_AUDIT_EVENTS |
1763 | PRIVSEP(audit_event(SSH_CONNECTION_CLOSE)); | |
1764 | #endif | |
1765 | ||
3c0ef626 | 1766 | packet_close(); |
510132b6 | 1767 | |
1768 | if (use_privsep) | |
1769 | mm_terminate(); | |
1770 | ||
3c0ef626 | 1771 | exit(0); |
1772 | } | |
1773 | ||
510132b6 | 1774 | /* |
1775 | * Decrypt session_key_int using our private server key and private host key | |
1776 | * (key with larger modulus first). | |
1777 | */ | |
1778 | int | |
1779 | ssh1_session_key(BIGNUM *session_key_int) | |
1780 | { | |
1781 | int rsafail = 0; | |
1782 | ||
1783 | if (BN_cmp(sensitive_data.server_key->rsa->n, sensitive_data.ssh1_host_key->rsa->n) > 0) { | |
1784 | /* Server key has bigger modulus. */ | |
1785 | if (BN_num_bits(sensitive_data.server_key->rsa->n) < | |
1786 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) + SSH_KEY_BITS_RESERVED) { | |
1787 | fatal("do_connection: %s: server_key %d < host_key %d + SSH_KEY_BITS_RESERVED %d", | |
1788 | get_remote_ipaddr(), | |
1789 | BN_num_bits(sensitive_data.server_key->rsa->n), | |
1790 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n), | |
1791 | SSH_KEY_BITS_RESERVED); | |
1792 | } | |
1793 | if (rsa_private_decrypt(session_key_int, session_key_int, | |
1794 | sensitive_data.server_key->rsa) <= 0) | |
1795 | rsafail++; | |
1796 | if (rsa_private_decrypt(session_key_int, session_key_int, | |
1797 | sensitive_data.ssh1_host_key->rsa) <= 0) | |
1798 | rsafail++; | |
1799 | } else { | |
1800 | /* Host key has bigger modulus (or they are equal). */ | |
1801 | if (BN_num_bits(sensitive_data.ssh1_host_key->rsa->n) < | |
1802 | BN_num_bits(sensitive_data.server_key->rsa->n) + SSH_KEY_BITS_RESERVED) { | |
1803 | fatal("do_connection: %s: host_key %d < server_key %d + SSH_KEY_BITS_RESERVED %d", | |
1804 | get_remote_ipaddr(), | |
1805 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n), | |
1806 | BN_num_bits(sensitive_data.server_key->rsa->n), | |
1807 | SSH_KEY_BITS_RESERVED); | |
1808 | } | |
1809 | if (rsa_private_decrypt(session_key_int, session_key_int, | |
1810 | sensitive_data.ssh1_host_key->rsa) < 0) | |
1811 | rsafail++; | |
1812 | if (rsa_private_decrypt(session_key_int, session_key_int, | |
1813 | sensitive_data.server_key->rsa) < 0) | |
1814 | rsafail++; | |
1815 | } | |
1816 | return (rsafail); | |
1817 | } | |
3c0ef626 | 1818 | /* |
1819 | * SSH1 key exchange | |
1820 | */ | |
1821 | static void | |
1822 | do_ssh1_kex(void) | |
1823 | { | |
1824 | int i, len; | |
3c0ef626 | 1825 | int rsafail = 0; |
1826 | BIGNUM *session_key_int; | |
1827 | u_char session_key[SSH_SESSION_KEY_LENGTH]; | |
1828 | u_char cookie[8]; | |
1829 | u_int cipher_type, auth_mask, protocol_flags; | |
d03f4262 | 1830 | u_int32_t rnd = 0; |
3c0ef626 | 1831 | |
1832 | /* | |
1833 | * Generate check bytes that the client must send back in the user | |
1834 | * packet in order for it to be accepted; this is used to defy ip | |
1835 | * spoofing attacks. Note that this only works against somebody | |
1836 | * doing IP spoofing from a remote machine; any machine on the local | |
1837 | * network can still see outgoing packets and catch the random | |
1838 | * cookie. This only affects rhosts authentication, and this is one | |
1839 | * of the reasons why it is inherently insecure. | |
1840 | */ | |
1841 | for (i = 0; i < 8; i++) { | |
1842 | if (i % 4 == 0) | |
d03f4262 | 1843 | rnd = arc4random(); |
1844 | cookie[i] = rnd & 0xff; | |
1845 | rnd >>= 8; | |
3c0ef626 | 1846 | } |
1847 | ||
1848 | /* | |
1849 | * Send our public key. We include in the packet 64 bits of random | |
1850 | * data that must be matched in the reply in order to prevent IP | |
1851 | * spoofing. | |
1852 | */ | |
1853 | packet_start(SSH_SMSG_PUBLIC_KEY); | |
1854 | for (i = 0; i < 8; i++) | |
1855 | packet_put_char(cookie[i]); | |
1856 | ||
1857 | /* Store our public server RSA key. */ | |
1858 | packet_put_int(BN_num_bits(sensitive_data.server_key->rsa->n)); | |
1859 | packet_put_bignum(sensitive_data.server_key->rsa->e); | |
1860 | packet_put_bignum(sensitive_data.server_key->rsa->n); | |
1861 | ||
1862 | /* Store our public host RSA key. */ | |
1863 | packet_put_int(BN_num_bits(sensitive_data.ssh1_host_key->rsa->n)); | |
1864 | packet_put_bignum(sensitive_data.ssh1_host_key->rsa->e); | |
1865 | packet_put_bignum(sensitive_data.ssh1_host_key->rsa->n); | |
1866 | ||
1867 | /* Put protocol flags. */ | |
1868 | packet_put_int(SSH_PROTOFLAG_HOST_IN_FWD_OPEN); | |
1869 | ||
1870 | /* Declare which ciphers we support. */ | |
1871 | packet_put_int(cipher_mask_ssh1(0)); | |
1872 | ||
1873 | /* Declare supported authentication types. */ | |
1874 | auth_mask = 0; | |
3c0ef626 | 1875 | if (options.rhosts_rsa_authentication) |
1876 | auth_mask |= 1 << SSH_AUTH_RHOSTS_RSA; | |
1877 | if (options.rsa_authentication) | |
1878 | auth_mask |= 1 << SSH_AUTH_RSA; | |
b59afbfe | 1879 | if (options.challenge_response_authentication == 1) |
1880 | auth_mask |= 1 << SSH_AUTH_TIS; | |
3c0ef626 | 1881 | if (options.password_authentication) |
1882 | auth_mask |= 1 << SSH_AUTH_PASSWORD; | |
1883 | packet_put_int(auth_mask); | |
1884 | ||
1885 | /* Send the packet and wait for it to be sent. */ | |
1886 | packet_send(); | |
1887 | packet_write_wait(); | |
1888 | ||
1889 | debug("Sent %d bit server key and %d bit host key.", | |
1890 | BN_num_bits(sensitive_data.server_key->rsa->n), | |
1891 | BN_num_bits(sensitive_data.ssh1_host_key->rsa->n)); | |
1892 | ||
1893 | /* Read clients reply (cipher type and session key). */ | |
1e608e42 | 1894 | packet_read_expect(SSH_CMSG_SESSION_KEY); |
3c0ef626 | 1895 | |
1896 | /* Get cipher type and check whether we accept this. */ | |
1897 | cipher_type = packet_get_char(); | |
1898 | ||
1899 | if (!(cipher_mask_ssh1(0) & (1 << cipher_type))) | |
1900 | packet_disconnect("Warning: client selects unsupported cipher."); | |
1901 | ||
1902 | /* Get check bytes from the packet. These must match those we | |
1903 | sent earlier with the public key packet. */ | |
1904 | for (i = 0; i < 8; i++) | |
1905 | if (cookie[i] != packet_get_char()) | |
1906 | packet_disconnect("IP Spoofing check bytes do not match."); | |
1907 | ||
1908 | debug("Encryption type: %.200s", cipher_name(cipher_type)); | |
1909 | ||
1910 | /* Get the encrypted integer. */ | |
1e608e42 | 1911 | if ((session_key_int = BN_new()) == NULL) |
1912 | fatal("do_ssh1_kex: BN_new failed"); | |
1913 | packet_get_bignum(session_key_int); | |
3c0ef626 | 1914 | |
1915 | protocol_flags = packet_get_int(); | |
1916 | packet_set_protocol_flags(protocol_flags); | |
1e608e42 | 1917 | packet_check_eom(); |
3c0ef626 | 1918 | |
510132b6 | 1919 | /* Decrypt session_key_int using host/server keys */ |
1920 | rsafail = PRIVSEP(ssh1_session_key(session_key_int)); | |
1921 | ||
3c0ef626 | 1922 | /* |
1923 | * Extract session key from the decrypted integer. The key is in the | |
1924 | * least significant 256 bits of the integer; the first byte of the | |
1925 | * key is in the highest bits. | |
1926 | */ | |
1927 | if (!rsafail) { | |
1928 | BN_mask_bits(session_key_int, sizeof(session_key) * 8); | |
1929 | len = BN_num_bytes(session_key_int); | |
2ce0bfe4 | 1930 | if (len < 0 || (u_int)len > sizeof(session_key)) { |
3c0ef626 | 1931 | error("do_connection: bad session key len from %s: " |
1932 | "session_key_int %d > sizeof(session_key) %lu", | |
1933 | get_remote_ipaddr(), len, (u_long)sizeof(session_key)); | |
1934 | rsafail++; | |
1935 | } else { | |
1936 | memset(session_key, 0, sizeof(session_key)); | |
1937 | BN_bn2bin(session_key_int, | |
1938 | session_key + sizeof(session_key) - len); | |
1939 | ||
7e82606e | 1940 | derive_ssh1_session_id( |
3c0ef626 | 1941 | sensitive_data.ssh1_host_key->rsa->n, |
7e82606e | 1942 | sensitive_data.server_key->rsa->n, |
1943 | cookie, session_id); | |
3c0ef626 | 1944 | /* |
1945 | * Xor the first 16 bytes of the session key with the | |
1946 | * session id. | |
1947 | */ | |
1948 | for (i = 0; i < 16; i++) | |
1949 | session_key[i] ^= session_id[i]; | |
1950 | } | |
1951 | } | |
1952 | if (rsafail) { | |
1953 | int bytes = BN_num_bytes(session_key_int); | |
1e608e42 | 1954 | u_char *buf = xmalloc(bytes); |
3c0ef626 | 1955 | MD5_CTX md; |
1956 | ||
7cac2b65 | 1957 | logit("do_connection: generating a fake encryption key"); |
3c0ef626 | 1958 | BN_bn2bin(session_key_int, buf); |
1959 | MD5_Init(&md); | |
1960 | MD5_Update(&md, buf, bytes); | |
1961 | MD5_Update(&md, sensitive_data.ssh1_cookie, SSH_SESSION_KEY_LENGTH); | |
1962 | MD5_Final(session_key, &md); | |
1963 | MD5_Init(&md); | |
1964 | MD5_Update(&md, session_key, 16); | |
1965 | MD5_Update(&md, buf, bytes); | |
1966 | MD5_Update(&md, sensitive_data.ssh1_cookie, SSH_SESSION_KEY_LENGTH); | |
1967 | MD5_Final(session_key + 16, &md); | |
1968 | memset(buf, 0, bytes); | |
1969 | xfree(buf); | |
1970 | for (i = 0; i < 16; i++) | |
1971 | session_id[i] = session_key[i] ^ session_key[i + 16]; | |
1972 | } | |
510132b6 | 1973 | /* Destroy the private and public keys. No longer. */ |
3c0ef626 | 1974 | destroy_sensitive_data(); |
1975 | ||
510132b6 | 1976 | if (use_privsep) |
1977 | mm_ssh1_session_id(session_id); | |
1978 | ||
3c0ef626 | 1979 | /* Destroy the decrypted integer. It is no longer needed. */ |
1980 | BN_clear_free(session_key_int); | |
1981 | ||
1982 | /* Set the session key. From this on all communications will be encrypted. */ | |
1983 | packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, cipher_type); | |
1984 | ||
1985 | /* Destroy our copy of the session key. It is no longer needed. */ | |
1986 | memset(session_key, 0, sizeof(session_key)); | |
1987 | ||
1988 | debug("Received session key; encryption turned on."); | |
1989 | ||
44a053a3 | 1990 | /* Send an acknowledgment packet. Note that this packet is sent encrypted. */ |
3c0ef626 | 1991 | packet_start(SSH_SMSG_SUCCESS); |
1992 | packet_send(); | |
1993 | packet_write_wait(); | |
1994 | } | |
1995 | ||
1996 | /* | |
1997 | * SSH2 key exchange: diffie-hellman-group1-sha1 | |
1998 | */ | |
1999 | static void | |
2000 | do_ssh2_kex(void) | |
2001 | { | |
2002 | Kex *kex; | |
2003 | ||
2004 | if (options.ciphers != NULL) { | |
2005 | myproposal[PROPOSAL_ENC_ALGS_CTOS] = | |
2006 | myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers; | |
2007 | } | |
2008 | myproposal[PROPOSAL_ENC_ALGS_CTOS] = | |
2009 | compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]); | |
2010 | myproposal[PROPOSAL_ENC_ALGS_STOC] = | |
2011 | compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]); | |
2012 | ||
2013 | if (options.macs != NULL) { | |
2014 | myproposal[PROPOSAL_MAC_ALGS_CTOS] = | |
2015 | myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs; | |
2016 | } | |
2ce0bfe4 | 2017 | if (options.compression == COMP_NONE) { |
44a053a3 | 2018 | myproposal[PROPOSAL_COMP_ALGS_CTOS] = |
2019 | myproposal[PROPOSAL_COMP_ALGS_STOC] = "none"; | |
2ce0bfe4 | 2020 | } else if (options.compression == COMP_DELAYED) { |
2021 | myproposal[PROPOSAL_COMP_ALGS_CTOS] = | |
2022 | myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com"; | |
44a053a3 | 2023 | } |
2ce0bfe4 | 2024 | |
3c0ef626 | 2025 | myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = list_hostkey_types(); |
2026 | ||
5598e598 | 2027 | #ifdef GSSAPI |
2028 | { | |
2029 | char *orig; | |
2030 | char *gss = NULL; | |
2031 | char *newstr = NULL; | |
2032 | orig = myproposal[PROPOSAL_KEX_ALGS]; | |
2033 | ||
2034 | /* If we don't have a host key, then all of the algorithms | |
2035 | * currently in myproposal are useless */ | |
2036 | if (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])==0) | |
2037 | orig= NULL; | |
2038 | ||
2039 | if (options.gss_keyex) | |
23987cb8 | 2040 | gss = ssh_gssapi_server_mechanisms(); |
5598e598 | 2041 | else |
2042 | gss = NULL; | |
2043 | ||
2044 | if (gss && orig) { | |
2045 | int len = strlen(orig) + strlen(gss) +2; | |
2046 | newstr=xmalloc(len); | |
2047 | snprintf(newstr,len,"%s,%s",gss,orig); | |
2048 | } else if (gss) { | |
2049 | newstr=gss; | |
2050 | } else if (orig) { | |
2051 | newstr=orig; | |
2052 | } | |
2053 | /* If we've got GSSAPI mechanisms, then we've also got the 'null' | |
2054 | host key algorithm, but we're not allowed to advertise it, unless | |
2055 | its the only host key algorithm we're supporting */ | |
2056 | if (gss && (strlen(myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS])) == 0) { | |
2057 | myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS]="null"; | |
2058 | } | |
2059 | if (newstr) | |
2060 | myproposal[PROPOSAL_KEX_ALGS]=newstr; | |
2061 | else | |
2062 | fatal("No supported key exchange algorithms"); | |
2063 | } | |
2064 | #endif | |
2065 | ||
3c0ef626 | 2066 | /* start key exchange */ |
2067 | kex = kex_setup(myproposal); | |
bfe49944 | 2068 | kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server; |
7e82606e | 2069 | kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server; |
bfe49944 | 2070 | kex->kex[KEX_DH_GEX_SHA1] = kexgex_server; |
2071 | #ifdef GSSAPI | |
2072 | kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_server; | |
2073 | #endif | |
3c0ef626 | 2074 | kex->server = 1; |
2075 | kex->client_version_string=client_version_string; | |
2076 | kex->server_version_string=server_version_string; | |
2077 | kex->load_host_key=&get_hostkey_by_type; | |
510132b6 | 2078 | kex->host_key_index=&get_hostkey_index; |
3c0ef626 | 2079 | |
2080 | xxx_kex = kex; | |
2081 | ||
2082 | dispatch_run(DISPATCH_BLOCK, &kex->done, kex); | |
2083 | ||
2084 | session_id2 = kex->session_id; | |
2085 | session_id2_len = kex->session_id_len; | |
2086 | ||
2087 | #ifdef DEBUG_KEXDH | |
2088 | /* send 1st encrypted/maced/compressed message */ | |
2089 | packet_start(SSH2_MSG_IGNORE); | |
2090 | packet_put_cstring("markus"); | |
2091 | packet_send(); | |
2092 | packet_write_wait(); | |
2093 | #endif | |
2094 | debug("KEX done"); | |
2095 | } | |
540d72c3 | 2096 | |
2097 | /* server specific fatal cleanup */ | |
2098 | void | |
2099 | cleanup_exit(int i) | |
2100 | { | |
2101 | if (the_authctxt) | |
2102 | do_cleanup(the_authctxt); | |
dfddba3d | 2103 | #ifdef SSH_AUDIT_EVENTS |
2104 | /* done after do_cleanup so it can cancel the PAM auth 'thread' */ | |
2105 | if (!use_privsep || mm_is_monitor()) | |
2106 | audit_event(SSH_CONNECTION_ABANDON); | |
2107 | #endif | |
540d72c3 | 2108 | _exit(i); |
2109 | } |