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fa0f0f45 | 1 | /* $OpenBSD: ssh-agent.c,v 1.155 2007/03/19 12:16:42 dtucker Exp $ */ |
3c0ef626 | 2 | /* |
3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> | |
4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland | |
5 | * All rights reserved | |
6 | * The authentication agent program. | |
7 | * | |
8 | * As far as I am concerned, the code I have written for this software | |
9 | * can be used freely for any purpose. Any derived versions of this | |
10 | * software must be clearly marked as such, and if the derived work is | |
11 | * incompatible with the protocol description in the RFC file, it must be | |
12 | * called by a name other than "ssh" or "Secure Shell". | |
13 | * | |
14 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
15 | * | |
16 | * Redistribution and use in source and binary forms, with or without | |
17 | * modification, are permitted provided that the following conditions | |
18 | * are met: | |
19 | * 1. Redistributions of source code must retain the above copyright | |
20 | * notice, this list of conditions and the following disclaimer. | |
21 | * 2. Redistributions in binary form must reproduce the above copyright | |
22 | * notice, this list of conditions and the following disclaimer in the | |
23 | * documentation and/or other materials provided with the distribution. | |
24 | * | |
25 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
26 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
27 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
28 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
29 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
30 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
31 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
32 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
33 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
34 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
35 | */ | |
36 | ||
37 | #include "includes.h" | |
30460aeb | 38 | |
39 | #include <sys/types.h> | |
40 | #include <sys/param.h> | |
41 | #include <sys/resource.h> | |
42 | #include <sys/stat.h> | |
43 | #include <sys/socket.h> | |
44 | #ifdef HAVE_SYS_TIME_H | |
45 | # include <sys/time.h> | |
46 | #endif | |
47 | #ifdef HAVE_SYS_UN_H | |
48 | # include <sys/un.h> | |
49 | #endif | |
d03f4262 | 50 | #include "openbsd-compat/sys-queue.h" |
3c0ef626 | 51 | |
52 | #include <openssl/evp.h> | |
53 | #include <openssl/md5.h> | |
54 | ||
30460aeb | 55 | #include <errno.h> |
56 | #include <fcntl.h> | |
57 | #ifdef HAVE_PATHS_H | |
58 | # include <paths.h> | |
59 | #endif | |
60 | #include <signal.h> | |
61 | #include <stdarg.h> | |
62 | #include <stdio.h> | |
63 | #include <stdlib.h> | |
64 | #include <time.h> | |
65 | #include <string.h> | |
66 | #include <unistd.h> | |
67 | ||
68 | #include "xmalloc.h" | |
3c0ef626 | 69 | #include "ssh.h" |
70 | #include "rsa.h" | |
71 | #include "buffer.h" | |
3c0ef626 | 72 | #include "key.h" |
73 | #include "authfd.h" | |
3c0ef626 | 74 | #include "compat.h" |
75 | #include "log.h" | |
bfe49944 | 76 | #include "misc.h" |
3c0ef626 | 77 | |
78 | #ifdef SMARTCARD | |
3c0ef626 | 79 | #include "scard.h" |
80 | #endif | |
81 | ||
12a403af | 82 | #if defined(HAVE_SYS_PRCTL_H) |
83 | #include <sys/prctl.h> /* For prctl() and PR_SET_DUMPABLE */ | |
84 | #endif | |
85 | ||
df84fde0 | 86 | typedef enum { |
87 | AUTH_UNUSED, | |
88 | AUTH_SOCKET, | |
89 | AUTH_CONNECTION | |
90 | } sock_type; | |
91 | ||
3c0ef626 | 92 | typedef struct { |
93 | int fd; | |
df84fde0 | 94 | sock_type type; |
3c0ef626 | 95 | Buffer input; |
96 | Buffer output; | |
df84fde0 | 97 | Buffer request; |
3c0ef626 | 98 | } SocketEntry; |
99 | ||
100 | u_int sockets_alloc = 0; | |
101 | SocketEntry *sockets = NULL; | |
102 | ||
df84fde0 | 103 | typedef struct identity { |
104 | TAILQ_ENTRY(identity) next; | |
3c0ef626 | 105 | Key *key; |
106 | char *comment; | |
df84fde0 | 107 | u_int death; |
bfe49944 | 108 | u_int confirm; |
3c0ef626 | 109 | } Identity; |
110 | ||
111 | typedef struct { | |
112 | int nentries; | |
df84fde0 | 113 | TAILQ_HEAD(idqueue, identity) idlist; |
3c0ef626 | 114 | } Idtab; |
115 | ||
116 | /* private key table, one per protocol version */ | |
117 | Idtab idtable[3]; | |
118 | ||
119 | int max_fd = 0; | |
120 | ||
121 | /* pid of shell == parent of agent */ | |
122 | pid_t parent_pid = -1; | |
fa0f0f45 | 123 | u_int parent_alive_interval = 0; |
3c0ef626 | 124 | |
125 | /* pathname and directory for AUTH_SOCKET */ | |
30460aeb | 126 | char socket_name[MAXPATHLEN]; |
127 | char socket_dir[MAXPATHLEN]; | |
3c0ef626 | 128 | |
df84fde0 | 129 | /* locking */ |
130 | int locked = 0; | |
131 | char *lock_passwd = NULL; | |
132 | ||
3c0ef626 | 133 | extern char *__progname; |
3c0ef626 | 134 | |
bfe49944 | 135 | /* Default lifetime (0 == forever) */ |
136 | static int lifetime = 0; | |
137 | ||
d03f4262 | 138 | static void |
139 | close_socket(SocketEntry *e) | |
140 | { | |
141 | close(e->fd); | |
142 | e->fd = -1; | |
143 | e->type = AUTH_UNUSED; | |
144 | buffer_free(&e->input); | |
145 | buffer_free(&e->output); | |
146 | buffer_free(&e->request); | |
147 | } | |
148 | ||
3c0ef626 | 149 | static void |
150 | idtab_init(void) | |
151 | { | |
152 | int i; | |
276b07a3 | 153 | |
df84fde0 | 154 | for (i = 0; i <=2; i++) { |
155 | TAILQ_INIT(&idtable[i].idlist); | |
3c0ef626 | 156 | idtable[i].nentries = 0; |
157 | } | |
158 | } | |
159 | ||
160 | /* return private key table for requested protocol version */ | |
161 | static Idtab * | |
162 | idtab_lookup(int version) | |
163 | { | |
164 | if (version < 1 || version > 2) | |
165 | fatal("internal error, bad protocol version %d", version); | |
166 | return &idtable[version]; | |
167 | } | |
168 | ||
df84fde0 | 169 | static void |
170 | free_identity(Identity *id) | |
171 | { | |
172 | key_free(id->key); | |
173 | xfree(id->comment); | |
174 | xfree(id); | |
175 | } | |
176 | ||
3c0ef626 | 177 | /* return matching private key for given public key */ |
df84fde0 | 178 | static Identity * |
179 | lookup_identity(Key *key, int version) | |
3c0ef626 | 180 | { |
df84fde0 | 181 | Identity *id; |
182 | ||
3c0ef626 | 183 | Idtab *tab = idtab_lookup(version); |
df84fde0 | 184 | TAILQ_FOREACH(id, &tab->idlist, next) { |
185 | if (key_equal(key, id->key)) | |
186 | return (id); | |
3c0ef626 | 187 | } |
df84fde0 | 188 | return (NULL); |
3c0ef626 | 189 | } |
190 | ||
bfe49944 | 191 | /* Check confirmation of keysign request */ |
192 | static int | |
193 | confirm_key(Identity *id) | |
194 | { | |
dfddba3d | 195 | char *p; |
bfe49944 | 196 | int ret = -1; |
197 | ||
198 | p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX); | |
dfddba3d | 199 | if (ask_permission("Allow use of key %s?\nKey fingerprint %s.", |
200 | id->comment, p)) | |
201 | ret = 0; | |
bfe49944 | 202 | xfree(p); |
dfddba3d | 203 | |
bfe49944 | 204 | return (ret); |
205 | } | |
206 | ||
3c0ef626 | 207 | /* send list of supported public keys to 'client' */ |
208 | static void | |
209 | process_request_identities(SocketEntry *e, int version) | |
210 | { | |
211 | Idtab *tab = idtab_lookup(version); | |
df84fde0 | 212 | Identity *id; |
276b07a3 | 213 | Buffer msg; |
3c0ef626 | 214 | |
215 | buffer_init(&msg); | |
216 | buffer_put_char(&msg, (version == 1) ? | |
217 | SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); | |
218 | buffer_put_int(&msg, tab->nentries); | |
df84fde0 | 219 | TAILQ_FOREACH(id, &tab->idlist, next) { |
3c0ef626 | 220 | if (id->key->type == KEY_RSA1) { |
221 | buffer_put_int(&msg, BN_num_bits(id->key->rsa->n)); | |
222 | buffer_put_bignum(&msg, id->key->rsa->e); | |
223 | buffer_put_bignum(&msg, id->key->rsa->n); | |
224 | } else { | |
225 | u_char *blob; | |
226 | u_int blen; | |
227 | key_to_blob(id->key, &blob, &blen); | |
228 | buffer_put_string(&msg, blob, blen); | |
229 | xfree(blob); | |
230 | } | |
231 | buffer_put_cstring(&msg, id->comment); | |
232 | } | |
233 | buffer_put_int(&e->output, buffer_len(&msg)); | |
234 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
235 | buffer_free(&msg); | |
236 | } | |
237 | ||
238 | /* ssh1 only */ | |
239 | static void | |
240 | process_authentication_challenge1(SocketEntry *e) | |
241 | { | |
276b07a3 | 242 | u_char buf[32], mdbuf[16], session_id[16]; |
243 | u_int response_type; | |
3c0ef626 | 244 | BIGNUM *challenge; |
276b07a3 | 245 | Identity *id; |
3c0ef626 | 246 | int i, len; |
247 | Buffer msg; | |
248 | MD5_CTX md; | |
276b07a3 | 249 | Key *key; |
3c0ef626 | 250 | |
251 | buffer_init(&msg); | |
252 | key = key_new(KEY_RSA1); | |
df84fde0 | 253 | if ((challenge = BN_new()) == NULL) |
254 | fatal("process_authentication_challenge1: BN_new failed"); | |
3c0ef626 | 255 | |
276b07a3 | 256 | (void) buffer_get_int(&e->request); /* ignored */ |
df84fde0 | 257 | buffer_get_bignum(&e->request, key->rsa->e); |
258 | buffer_get_bignum(&e->request, key->rsa->n); | |
259 | buffer_get_bignum(&e->request, challenge); | |
3c0ef626 | 260 | |
261 | /* Only protocol 1.1 is supported */ | |
df84fde0 | 262 | if (buffer_len(&e->request) == 0) |
3c0ef626 | 263 | goto failure; |
df84fde0 | 264 | buffer_get(&e->request, session_id, 16); |
265 | response_type = buffer_get_int(&e->request); | |
3c0ef626 | 266 | if (response_type != 1) |
267 | goto failure; | |
268 | ||
df84fde0 | 269 | id = lookup_identity(key, 1); |
bfe49944 | 270 | if (id != NULL && (!id->confirm || confirm_key(id) == 0)) { |
df84fde0 | 271 | Key *private = id->key; |
3c0ef626 | 272 | /* Decrypt the challenge using the private key. */ |
273 | if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0) | |
274 | goto failure; | |
275 | ||
276 | /* The response is MD5 of decrypted challenge plus session id. */ | |
277 | len = BN_num_bytes(challenge); | |
278 | if (len <= 0 || len > 32) { | |
7cac2b65 | 279 | logit("process_authentication_challenge: bad challenge length %d", len); |
3c0ef626 | 280 | goto failure; |
281 | } | |
282 | memset(buf, 0, 32); | |
283 | BN_bn2bin(challenge, buf + 32 - len); | |
284 | MD5_Init(&md); | |
285 | MD5_Update(&md, buf, 32); | |
286 | MD5_Update(&md, session_id, 16); | |
287 | MD5_Final(mdbuf, &md); | |
288 | ||
289 | /* Send the response. */ | |
290 | buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE); | |
291 | for (i = 0; i < 16; i++) | |
292 | buffer_put_char(&msg, mdbuf[i]); | |
293 | goto send; | |
294 | } | |
295 | ||
296 | failure: | |
297 | /* Unknown identity or protocol error. Send failure. */ | |
298 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
299 | send: | |
300 | buffer_put_int(&e->output, buffer_len(&msg)); | |
301 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
302 | key_free(key); | |
303 | BN_clear_free(challenge); | |
304 | buffer_free(&msg); | |
305 | } | |
306 | ||
307 | /* ssh2 only */ | |
308 | static void | |
309 | process_sign_request2(SocketEntry *e) | |
310 | { | |
3c0ef626 | 311 | u_char *blob, *data, *signature = NULL; |
312 | u_int blen, dlen, slen = 0; | |
276b07a3 | 313 | extern int datafellows; |
314 | int ok = -1, flags; | |
3c0ef626 | 315 | Buffer msg; |
276b07a3 | 316 | Key *key; |
3c0ef626 | 317 | |
318 | datafellows = 0; | |
319 | ||
df84fde0 | 320 | blob = buffer_get_string(&e->request, &blen); |
321 | data = buffer_get_string(&e->request, &dlen); | |
3c0ef626 | 322 | |
df84fde0 | 323 | flags = buffer_get_int(&e->request); |
3c0ef626 | 324 | if (flags & SSH_AGENT_OLD_SIGNATURE) |
325 | datafellows = SSH_BUG_SIGBLOB; | |
326 | ||
327 | key = key_from_blob(blob, blen); | |
328 | if (key != NULL) { | |
df84fde0 | 329 | Identity *id = lookup_identity(key, 2); |
bfe49944 | 330 | if (id != NULL && (!id->confirm || confirm_key(id) == 0)) |
df84fde0 | 331 | ok = key_sign(id->key, &signature, &slen, data, dlen); |
30460aeb | 332 | key_free(key); |
3c0ef626 | 333 | } |
3c0ef626 | 334 | buffer_init(&msg); |
335 | if (ok == 0) { | |
336 | buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE); | |
337 | buffer_put_string(&msg, signature, slen); | |
338 | } else { | |
339 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
340 | } | |
341 | buffer_put_int(&e->output, buffer_len(&msg)); | |
342 | buffer_append(&e->output, buffer_ptr(&msg), | |
343 | buffer_len(&msg)); | |
344 | buffer_free(&msg); | |
345 | xfree(data); | |
346 | xfree(blob); | |
347 | if (signature != NULL) | |
348 | xfree(signature); | |
349 | } | |
350 | ||
351 | /* shared */ | |
352 | static void | |
353 | process_remove_identity(SocketEntry *e, int version) | |
354 | { | |
276b07a3 | 355 | u_int blen, bits; |
356 | int success = 0; | |
df84fde0 | 357 | Key *key = NULL; |
3c0ef626 | 358 | u_char *blob; |
3c0ef626 | 359 | |
df84fde0 | 360 | switch (version) { |
3c0ef626 | 361 | case 1: |
362 | key = key_new(KEY_RSA1); | |
df84fde0 | 363 | bits = buffer_get_int(&e->request); |
364 | buffer_get_bignum(&e->request, key->rsa->e); | |
365 | buffer_get_bignum(&e->request, key->rsa->n); | |
3c0ef626 | 366 | |
367 | if (bits != key_size(key)) | |
7cac2b65 | 368 | logit("Warning: identity keysize mismatch: actual %u, announced %u", |
3c0ef626 | 369 | key_size(key), bits); |
370 | break; | |
371 | case 2: | |
df84fde0 | 372 | blob = buffer_get_string(&e->request, &blen); |
3c0ef626 | 373 | key = key_from_blob(blob, blen); |
374 | xfree(blob); | |
375 | break; | |
376 | } | |
377 | if (key != NULL) { | |
df84fde0 | 378 | Identity *id = lookup_identity(key, version); |
379 | if (id != NULL) { | |
3c0ef626 | 380 | /* |
381 | * We have this key. Free the old key. Since we | |
08822d99 | 382 | * don't want to leave empty slots in the middle of |
3c0ef626 | 383 | * the array, we actually free the key there and move |
384 | * all the entries between the empty slot and the end | |
385 | * of the array. | |
386 | */ | |
387 | Idtab *tab = idtab_lookup(version); | |
3c0ef626 | 388 | if (tab->nentries < 1) |
389 | fatal("process_remove_identity: " | |
390 | "internal error: tab->nentries %d", | |
391 | tab->nentries); | |
df84fde0 | 392 | TAILQ_REMOVE(&tab->idlist, id, next); |
393 | free_identity(id); | |
3c0ef626 | 394 | tab->nentries--; |
395 | success = 1; | |
396 | } | |
397 | key_free(key); | |
398 | } | |
399 | buffer_put_int(&e->output, 1); | |
400 | buffer_put_char(&e->output, | |
401 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
402 | } | |
403 | ||
404 | static void | |
405 | process_remove_all_identities(SocketEntry *e, int version) | |
406 | { | |
3c0ef626 | 407 | Idtab *tab = idtab_lookup(version); |
df84fde0 | 408 | Identity *id; |
3c0ef626 | 409 | |
410 | /* Loop over all identities and clear the keys. */ | |
df84fde0 | 411 | for (id = TAILQ_FIRST(&tab->idlist); id; |
412 | id = TAILQ_FIRST(&tab->idlist)) { | |
413 | TAILQ_REMOVE(&tab->idlist, id, next); | |
414 | free_identity(id); | |
3c0ef626 | 415 | } |
416 | ||
417 | /* Mark that there are no identities. */ | |
418 | tab->nentries = 0; | |
419 | ||
420 | /* Send success. */ | |
421 | buffer_put_int(&e->output, 1); | |
422 | buffer_put_char(&e->output, SSH_AGENT_SUCCESS); | |
df84fde0 | 423 | } |
424 | ||
fa0f0f45 | 425 | /* removes expired keys and returns number of seconds until the next expiry */ |
426 | static u_int | |
df84fde0 | 427 | reaper(void) |
428 | { | |
fa0f0f45 | 429 | u_int deadline = 0, now = time(NULL); |
df84fde0 | 430 | Identity *id, *nxt; |
431 | int version; | |
276b07a3 | 432 | Idtab *tab; |
df84fde0 | 433 | |
434 | for (version = 1; version < 3; version++) { | |
435 | tab = idtab_lookup(version); | |
436 | for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { | |
437 | nxt = TAILQ_NEXT(id, next); | |
fa0f0f45 | 438 | if (id->death == 0) |
439 | continue; | |
440 | if (now >= id->death) { | |
0b90ac93 | 441 | debug("expiring key '%s'", id->comment); |
df84fde0 | 442 | TAILQ_REMOVE(&tab->idlist, id, next); |
443 | free_identity(id); | |
444 | tab->nentries--; | |
fa0f0f45 | 445 | } else |
446 | deadline = (deadline == 0) ? id->death : | |
447 | MIN(deadline, id->death); | |
df84fde0 | 448 | } |
449 | } | |
fa0f0f45 | 450 | if (deadline == 0 || deadline <= now) |
451 | return 0; | |
452 | else | |
453 | return (deadline - now); | |
3c0ef626 | 454 | } |
455 | ||
456 | static void | |
457 | process_add_identity(SocketEntry *e, int version) | |
458 | { | |
3c0ef626 | 459 | Idtab *tab = idtab_lookup(version); |
bfe49944 | 460 | int type, success = 0, death = 0, confirm = 0; |
276b07a3 | 461 | char *type_name, *comment; |
462 | Key *k = NULL; | |
3c0ef626 | 463 | |
464 | switch (version) { | |
465 | case 1: | |
466 | k = key_new_private(KEY_RSA1); | |
276b07a3 | 467 | (void) buffer_get_int(&e->request); /* ignored */ |
df84fde0 | 468 | buffer_get_bignum(&e->request, k->rsa->n); |
469 | buffer_get_bignum(&e->request, k->rsa->e); | |
470 | buffer_get_bignum(&e->request, k->rsa->d); | |
471 | buffer_get_bignum(&e->request, k->rsa->iqmp); | |
3c0ef626 | 472 | |
473 | /* SSH and SSL have p and q swapped */ | |
df84fde0 | 474 | buffer_get_bignum(&e->request, k->rsa->q); /* p */ |
475 | buffer_get_bignum(&e->request, k->rsa->p); /* q */ | |
3c0ef626 | 476 | |
477 | /* Generate additional parameters */ | |
478 | rsa_generate_additional_parameters(k->rsa); | |
479 | break; | |
480 | case 2: | |
df84fde0 | 481 | type_name = buffer_get_string(&e->request, NULL); |
3c0ef626 | 482 | type = key_type_from_name(type_name); |
483 | xfree(type_name); | |
df84fde0 | 484 | switch (type) { |
3c0ef626 | 485 | case KEY_DSA: |
486 | k = key_new_private(type); | |
df84fde0 | 487 | buffer_get_bignum2(&e->request, k->dsa->p); |
488 | buffer_get_bignum2(&e->request, k->dsa->q); | |
489 | buffer_get_bignum2(&e->request, k->dsa->g); | |
490 | buffer_get_bignum2(&e->request, k->dsa->pub_key); | |
491 | buffer_get_bignum2(&e->request, k->dsa->priv_key); | |
3c0ef626 | 492 | break; |
493 | case KEY_RSA: | |
494 | k = key_new_private(type); | |
df84fde0 | 495 | buffer_get_bignum2(&e->request, k->rsa->n); |
496 | buffer_get_bignum2(&e->request, k->rsa->e); | |
497 | buffer_get_bignum2(&e->request, k->rsa->d); | |
498 | buffer_get_bignum2(&e->request, k->rsa->iqmp); | |
499 | buffer_get_bignum2(&e->request, k->rsa->p); | |
500 | buffer_get_bignum2(&e->request, k->rsa->q); | |
3c0ef626 | 501 | |
502 | /* Generate additional parameters */ | |
503 | rsa_generate_additional_parameters(k->rsa); | |
504 | break; | |
505 | default: | |
df84fde0 | 506 | buffer_clear(&e->request); |
3c0ef626 | 507 | goto send; |
508 | } | |
509 | break; | |
510 | } | |
bfe49944 | 511 | /* enable blinding */ |
512 | switch (k->type) { | |
513 | case KEY_RSA: | |
514 | case KEY_RSA1: | |
515 | if (RSA_blinding_on(k->rsa, NULL) != 1) { | |
516 | error("process_add_identity: RSA_blinding_on failed"); | |
517 | key_free(k); | |
518 | goto send; | |
519 | } | |
520 | break; | |
521 | } | |
df84fde0 | 522 | comment = buffer_get_string(&e->request, NULL); |
3c0ef626 | 523 | if (k == NULL) { |
524 | xfree(comment); | |
525 | goto send; | |
526 | } | |
527 | success = 1; | |
df84fde0 | 528 | while (buffer_len(&e->request)) { |
529 | switch (buffer_get_char(&e->request)) { | |
530 | case SSH_AGENT_CONSTRAIN_LIFETIME: | |
531 | death = time(NULL) + buffer_get_int(&e->request); | |
532 | break; | |
bfe49944 | 533 | case SSH_AGENT_CONSTRAIN_CONFIRM: |
534 | confirm = 1; | |
535 | break; | |
df84fde0 | 536 | default: |
537 | break; | |
538 | } | |
539 | } | |
bfe49944 | 540 | if (lifetime && !death) |
541 | death = time(NULL) + lifetime; | |
df84fde0 | 542 | if (lookup_identity(k, version) == NULL) { |
543 | Identity *id = xmalloc(sizeof(Identity)); | |
544 | id->key = k; | |
545 | id->comment = comment; | |
546 | id->death = death; | |
bfe49944 | 547 | id->confirm = confirm; |
df84fde0 | 548 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); |
3c0ef626 | 549 | /* Increment the number of identities. */ |
550 | tab->nentries++; | |
551 | } else { | |
552 | key_free(k); | |
553 | xfree(comment); | |
554 | } | |
555 | send: | |
556 | buffer_put_int(&e->output, 1); | |
557 | buffer_put_char(&e->output, | |
558 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
559 | } | |
560 | ||
df84fde0 | 561 | /* XXX todo: encrypt sensitive data with passphrase */ |
562 | static void | |
563 | process_lock_agent(SocketEntry *e, int lock) | |
564 | { | |
df84fde0 | 565 | int success = 0; |
276b07a3 | 566 | char *passwd; |
df84fde0 | 567 | |
568 | passwd = buffer_get_string(&e->request, NULL); | |
569 | if (locked && !lock && strcmp(passwd, lock_passwd) == 0) { | |
570 | locked = 0; | |
571 | memset(lock_passwd, 0, strlen(lock_passwd)); | |
572 | xfree(lock_passwd); | |
573 | lock_passwd = NULL; | |
574 | success = 1; | |
575 | } else if (!locked && lock) { | |
576 | locked = 1; | |
577 | lock_passwd = xstrdup(passwd); | |
578 | success = 1; | |
579 | } | |
580 | memset(passwd, 0, strlen(passwd)); | |
581 | xfree(passwd); | |
582 | ||
583 | buffer_put_int(&e->output, 1); | |
584 | buffer_put_char(&e->output, | |
585 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
586 | } | |
587 | ||
588 | static void | |
589 | no_identities(SocketEntry *e, u_int type) | |
590 | { | |
591 | Buffer msg; | |
592 | ||
593 | buffer_init(&msg); | |
594 | buffer_put_char(&msg, | |
595 | (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ? | |
596 | SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); | |
597 | buffer_put_int(&msg, 0); | |
598 | buffer_put_int(&e->output, buffer_len(&msg)); | |
599 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
600 | buffer_free(&msg); | |
601 | } | |
3c0ef626 | 602 | |
603 | #ifdef SMARTCARD | |
604 | static void | |
605 | process_add_smartcard_key (SocketEntry *e) | |
606 | { | |
df84fde0 | 607 | char *sc_reader_id = NULL, *pin; |
7cac2b65 | 608 | int i, version, success = 0, death = 0, confirm = 0; |
276b07a3 | 609 | Key **keys, *k; |
610 | Identity *id; | |
611 | Idtab *tab; | |
df84fde0 | 612 | |
613 | sc_reader_id = buffer_get_string(&e->request, NULL); | |
614 | pin = buffer_get_string(&e->request, NULL); | |
7cac2b65 | 615 | |
616 | while (buffer_len(&e->request)) { | |
617 | switch (buffer_get_char(&e->request)) { | |
618 | case SSH_AGENT_CONSTRAIN_LIFETIME: | |
619 | death = time(NULL) + buffer_get_int(&e->request); | |
620 | break; | |
621 | case SSH_AGENT_CONSTRAIN_CONFIRM: | |
622 | confirm = 1; | |
623 | break; | |
624 | default: | |
625 | break; | |
626 | } | |
627 | } | |
628 | if (lifetime && !death) | |
629 | death = time(NULL) + lifetime; | |
630 | ||
df84fde0 | 631 | keys = sc_get_keys(sc_reader_id, pin); |
3c0ef626 | 632 | xfree(sc_reader_id); |
df84fde0 | 633 | xfree(pin); |
3c0ef626 | 634 | |
df84fde0 | 635 | if (keys == NULL || keys[0] == NULL) { |
636 | error("sc_get_keys failed"); | |
3c0ef626 | 637 | goto send; |
638 | } | |
df84fde0 | 639 | for (i = 0; keys[i] != NULL; i++) { |
640 | k = keys[i]; | |
641 | version = k->type == KEY_RSA1 ? 1 : 2; | |
642 | tab = idtab_lookup(version); | |
643 | if (lookup_identity(k, version) == NULL) { | |
644 | id = xmalloc(sizeof(Identity)); | |
645 | id->key = k; | |
7cac2b65 | 646 | id->comment = sc_get_key_label(k); |
647 | id->death = death; | |
648 | id->confirm = confirm; | |
df84fde0 | 649 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); |
650 | tab->nentries++; | |
651 | success = 1; | |
652 | } else { | |
653 | key_free(k); | |
654 | } | |
655 | keys[i] = NULL; | |
3c0ef626 | 656 | } |
df84fde0 | 657 | xfree(keys); |
3c0ef626 | 658 | send: |
659 | buffer_put_int(&e->output, 1); | |
660 | buffer_put_char(&e->output, | |
661 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
662 | } | |
663 | ||
664 | static void | |
665 | process_remove_smartcard_key(SocketEntry *e) | |
666 | { | |
df84fde0 | 667 | char *sc_reader_id = NULL, *pin; |
668 | int i, version, success = 0; | |
276b07a3 | 669 | Key **keys, *k = NULL; |
670 | Identity *id; | |
671 | Idtab *tab; | |
3c0ef626 | 672 | |
df84fde0 | 673 | sc_reader_id = buffer_get_string(&e->request, NULL); |
674 | pin = buffer_get_string(&e->request, NULL); | |
675 | keys = sc_get_keys(sc_reader_id, pin); | |
3c0ef626 | 676 | xfree(sc_reader_id); |
df84fde0 | 677 | xfree(pin); |
3c0ef626 | 678 | |
df84fde0 | 679 | if (keys == NULL || keys[0] == NULL) { |
680 | error("sc_get_keys failed"); | |
681 | goto send; | |
682 | } | |
683 | for (i = 0; keys[i] != NULL; i++) { | |
684 | k = keys[i]; | |
685 | version = k->type == KEY_RSA1 ? 1 : 2; | |
686 | if ((id = lookup_identity(k, version)) != NULL) { | |
687 | tab = idtab_lookup(version); | |
688 | TAILQ_REMOVE(&tab->idlist, id, next); | |
3c0ef626 | 689 | tab->nentries--; |
df84fde0 | 690 | free_identity(id); |
3c0ef626 | 691 | success = 1; |
692 | } | |
693 | key_free(k); | |
df84fde0 | 694 | keys[i] = NULL; |
3c0ef626 | 695 | } |
df84fde0 | 696 | xfree(keys); |
697 | send: | |
3c0ef626 | 698 | buffer_put_int(&e->output, 1); |
699 | buffer_put_char(&e->output, | |
700 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
701 | } | |
702 | #endif /* SMARTCARD */ | |
703 | ||
704 | /* dispatch incoming messages */ | |
705 | ||
706 | static void | |
707 | process_message(SocketEntry *e) | |
708 | { | |
276b07a3 | 709 | u_int msg_len, type; |
3c0ef626 | 710 | u_char *cp; |
df84fde0 | 711 | |
3c0ef626 | 712 | if (buffer_len(&e->input) < 5) |
713 | return; /* Incomplete message. */ | |
df84fde0 | 714 | cp = buffer_ptr(&e->input); |
30460aeb | 715 | msg_len = get_u32(cp); |
3c0ef626 | 716 | if (msg_len > 256 * 1024) { |
d03f4262 | 717 | close_socket(e); |
3c0ef626 | 718 | return; |
719 | } | |
720 | if (buffer_len(&e->input) < msg_len + 4) | |
721 | return; | |
df84fde0 | 722 | |
723 | /* move the current input to e->request */ | |
3c0ef626 | 724 | buffer_consume(&e->input, 4); |
df84fde0 | 725 | buffer_clear(&e->request); |
726 | buffer_append(&e->request, buffer_ptr(&e->input), msg_len); | |
727 | buffer_consume(&e->input, msg_len); | |
728 | type = buffer_get_char(&e->request); | |
729 | ||
730 | /* check wheter agent is locked */ | |
731 | if (locked && type != SSH_AGENTC_UNLOCK) { | |
732 | buffer_clear(&e->request); | |
733 | switch (type) { | |
734 | case SSH_AGENTC_REQUEST_RSA_IDENTITIES: | |
735 | case SSH2_AGENTC_REQUEST_IDENTITIES: | |
736 | /* send empty lists */ | |
737 | no_identities(e, type); | |
738 | break; | |
739 | default: | |
740 | /* send a fail message for all other request types */ | |
741 | buffer_put_int(&e->output, 1); | |
742 | buffer_put_char(&e->output, SSH_AGENT_FAILURE); | |
743 | } | |
744 | return; | |
745 | } | |
3c0ef626 | 746 | |
747 | debug("type %d", type); | |
748 | switch (type) { | |
df84fde0 | 749 | case SSH_AGENTC_LOCK: |
750 | case SSH_AGENTC_UNLOCK: | |
751 | process_lock_agent(e, type == SSH_AGENTC_LOCK); | |
752 | break; | |
3c0ef626 | 753 | /* ssh1 */ |
754 | case SSH_AGENTC_RSA_CHALLENGE: | |
755 | process_authentication_challenge1(e); | |
756 | break; | |
757 | case SSH_AGENTC_REQUEST_RSA_IDENTITIES: | |
758 | process_request_identities(e, 1); | |
759 | break; | |
760 | case SSH_AGENTC_ADD_RSA_IDENTITY: | |
df84fde0 | 761 | case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED: |
3c0ef626 | 762 | process_add_identity(e, 1); |
763 | break; | |
764 | case SSH_AGENTC_REMOVE_RSA_IDENTITY: | |
765 | process_remove_identity(e, 1); | |
766 | break; | |
767 | case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: | |
768 | process_remove_all_identities(e, 1); | |
769 | break; | |
770 | /* ssh2 */ | |
771 | case SSH2_AGENTC_SIGN_REQUEST: | |
772 | process_sign_request2(e); | |
773 | break; | |
774 | case SSH2_AGENTC_REQUEST_IDENTITIES: | |
775 | process_request_identities(e, 2); | |
776 | break; | |
777 | case SSH2_AGENTC_ADD_IDENTITY: | |
df84fde0 | 778 | case SSH2_AGENTC_ADD_ID_CONSTRAINED: |
3c0ef626 | 779 | process_add_identity(e, 2); |
780 | break; | |
781 | case SSH2_AGENTC_REMOVE_IDENTITY: | |
782 | process_remove_identity(e, 2); | |
783 | break; | |
784 | case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: | |
785 | process_remove_all_identities(e, 2); | |
786 | break; | |
787 | #ifdef SMARTCARD | |
788 | case SSH_AGENTC_ADD_SMARTCARD_KEY: | |
7cac2b65 | 789 | case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED: |
3c0ef626 | 790 | process_add_smartcard_key(e); |
df84fde0 | 791 | break; |
3c0ef626 | 792 | case SSH_AGENTC_REMOVE_SMARTCARD_KEY: |
793 | process_remove_smartcard_key(e); | |
df84fde0 | 794 | break; |
3c0ef626 | 795 | #endif /* SMARTCARD */ |
796 | default: | |
797 | /* Unknown message. Respond with failure. */ | |
798 | error("Unknown message %d", type); | |
df84fde0 | 799 | buffer_clear(&e->request); |
3c0ef626 | 800 | buffer_put_int(&e->output, 1); |
801 | buffer_put_char(&e->output, SSH_AGENT_FAILURE); | |
802 | break; | |
803 | } | |
804 | } | |
805 | ||
806 | static void | |
df84fde0 | 807 | new_socket(sock_type type, int fd) |
3c0ef626 | 808 | { |
29d88157 | 809 | u_int i, old_alloc, new_alloc; |
276b07a3 | 810 | |
7e82606e | 811 | set_nonblock(fd); |
3c0ef626 | 812 | |
813 | if (fd > max_fd) | |
814 | max_fd = fd; | |
815 | ||
816 | for (i = 0; i < sockets_alloc; i++) | |
817 | if (sockets[i].type == AUTH_UNUSED) { | |
818 | sockets[i].fd = fd; | |
3c0ef626 | 819 | buffer_init(&sockets[i].input); |
820 | buffer_init(&sockets[i].output); | |
df84fde0 | 821 | buffer_init(&sockets[i].request); |
29d88157 | 822 | sockets[i].type = type; |
3c0ef626 | 823 | return; |
824 | } | |
825 | old_alloc = sockets_alloc; | |
29d88157 | 826 | new_alloc = sockets_alloc + 10; |
30460aeb | 827 | sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0])); |
29d88157 | 828 | for (i = old_alloc; i < new_alloc; i++) |
3c0ef626 | 829 | sockets[i].type = AUTH_UNUSED; |
29d88157 | 830 | sockets_alloc = new_alloc; |
3c0ef626 | 831 | sockets[old_alloc].fd = fd; |
832 | buffer_init(&sockets[old_alloc].input); | |
833 | buffer_init(&sockets[old_alloc].output); | |
df84fde0 | 834 | buffer_init(&sockets[old_alloc].request); |
29d88157 | 835 | sockets[old_alloc].type = type; |
3c0ef626 | 836 | } |
837 | ||
838 | static int | |
fa0f0f45 | 839 | prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp, |
840 | struct timeval **tvpp) | |
3c0ef626 | 841 | { |
fa0f0f45 | 842 | u_int i, sz, deadline; |
3c0ef626 | 843 | int n = 0; |
fa0f0f45 | 844 | static struct timeval tv; |
3c0ef626 | 845 | |
846 | for (i = 0; i < sockets_alloc; i++) { | |
847 | switch (sockets[i].type) { | |
848 | case AUTH_SOCKET: | |
849 | case AUTH_CONNECTION: | |
850 | n = MAX(n, sockets[i].fd); | |
851 | break; | |
852 | case AUTH_UNUSED: | |
853 | break; | |
854 | default: | |
855 | fatal("Unknown socket type %d", sockets[i].type); | |
856 | break; | |
857 | } | |
858 | } | |
859 | ||
860 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
861 | if (*fdrp == NULL || sz > *nallocp) { | |
862 | if (*fdrp) | |
863 | xfree(*fdrp); | |
864 | if (*fdwp) | |
865 | xfree(*fdwp); | |
866 | *fdrp = xmalloc(sz); | |
867 | *fdwp = xmalloc(sz); | |
868 | *nallocp = sz; | |
869 | } | |
870 | if (n < *fdl) | |
871 | debug("XXX shrink: %d < %d", n, *fdl); | |
872 | *fdl = n; | |
873 | memset(*fdrp, 0, sz); | |
874 | memset(*fdwp, 0, sz); | |
875 | ||
876 | for (i = 0; i < sockets_alloc; i++) { | |
877 | switch (sockets[i].type) { | |
878 | case AUTH_SOCKET: | |
879 | case AUTH_CONNECTION: | |
880 | FD_SET(sockets[i].fd, *fdrp); | |
881 | if (buffer_len(&sockets[i].output) > 0) | |
882 | FD_SET(sockets[i].fd, *fdwp); | |
883 | break; | |
884 | default: | |
885 | break; | |
886 | } | |
887 | } | |
fa0f0f45 | 888 | deadline = reaper(); |
889 | if (parent_alive_interval != 0) | |
890 | deadline = (deadline == 0) ? parent_alive_interval : | |
891 | MIN(deadline, parent_alive_interval); | |
892 | if (deadline == 0) { | |
893 | *tvpp = NULL; | |
894 | } else { | |
895 | tv.tv_sec = deadline; | |
896 | tv.tv_usec = 0; | |
897 | *tvpp = &tv; | |
898 | } | |
3c0ef626 | 899 | return (1); |
900 | } | |
901 | ||
902 | static void | |
903 | after_select(fd_set *readset, fd_set *writeset) | |
904 | { | |
276b07a3 | 905 | struct sockaddr_un sunaddr; |
3c0ef626 | 906 | socklen_t slen; |
907 | char buf[1024]; | |
276b07a3 | 908 | int len, sock; |
909 | u_int i; | |
d03f4262 | 910 | uid_t euid; |
911 | gid_t egid; | |
3c0ef626 | 912 | |
913 | for (i = 0; i < sockets_alloc; i++) | |
914 | switch (sockets[i].type) { | |
915 | case AUTH_UNUSED: | |
916 | break; | |
917 | case AUTH_SOCKET: | |
918 | if (FD_ISSET(sockets[i].fd, readset)) { | |
919 | slen = sizeof(sunaddr); | |
920 | sock = accept(sockets[i].fd, | |
30460aeb | 921 | (struct sockaddr *)&sunaddr, &slen); |
3c0ef626 | 922 | if (sock < 0) { |
df84fde0 | 923 | error("accept from AUTH_SOCKET: %s", |
924 | strerror(errno)); | |
3c0ef626 | 925 | break; |
926 | } | |
d03f4262 | 927 | if (getpeereid(sock, &euid, &egid) < 0) { |
928 | error("getpeereid %d failed: %s", | |
929 | sock, strerror(errno)); | |
930 | close(sock); | |
931 | break; | |
932 | } | |
933 | if ((euid != 0) && (getuid() != euid)) { | |
934 | error("uid mismatch: " | |
935 | "peer euid %u != uid %u", | |
936 | (u_int) euid, (u_int) getuid()); | |
937 | close(sock); | |
938 | break; | |
939 | } | |
3c0ef626 | 940 | new_socket(AUTH_CONNECTION, sock); |
941 | } | |
942 | break; | |
943 | case AUTH_CONNECTION: | |
944 | if (buffer_len(&sockets[i].output) > 0 && | |
945 | FD_ISSET(sockets[i].fd, writeset)) { | |
946 | do { | |
947 | len = write(sockets[i].fd, | |
948 | buffer_ptr(&sockets[i].output), | |
949 | buffer_len(&sockets[i].output)); | |
950 | if (len == -1 && (errno == EAGAIN || | |
951 | errno == EINTR)) | |
952 | continue; | |
953 | break; | |
954 | } while (1); | |
955 | if (len <= 0) { | |
d03f4262 | 956 | close_socket(&sockets[i]); |
3c0ef626 | 957 | break; |
958 | } | |
959 | buffer_consume(&sockets[i].output, len); | |
960 | } | |
961 | if (FD_ISSET(sockets[i].fd, readset)) { | |
962 | do { | |
963 | len = read(sockets[i].fd, buf, sizeof(buf)); | |
964 | if (len == -1 && (errno == EAGAIN || | |
965 | errno == EINTR)) | |
966 | continue; | |
967 | break; | |
968 | } while (1); | |
969 | if (len <= 0) { | |
d03f4262 | 970 | close_socket(&sockets[i]); |
3c0ef626 | 971 | break; |
972 | } | |
973 | buffer_append(&sockets[i].input, buf, len); | |
974 | process_message(&sockets[i]); | |
975 | } | |
976 | break; | |
977 | default: | |
978 | fatal("Unknown type %d", sockets[i].type); | |
979 | } | |
980 | } | |
981 | ||
982 | static void | |
540d72c3 | 983 | cleanup_socket(void) |
3c0ef626 | 984 | { |
985 | if (socket_name[0]) | |
986 | unlink(socket_name); | |
987 | if (socket_dir[0]) | |
988 | rmdir(socket_dir); | |
989 | } | |
990 | ||
540d72c3 | 991 | void |
3c0ef626 | 992 | cleanup_exit(int i) |
993 | { | |
540d72c3 | 994 | cleanup_socket(); |
995 | _exit(i); | |
3c0ef626 | 996 | } |
997 | ||
30460aeb | 998 | /*ARGSUSED*/ |
3c0ef626 | 999 | static void |
1000 | cleanup_handler(int sig) | |
1001 | { | |
540d72c3 | 1002 | cleanup_socket(); |
3c0ef626 | 1003 | _exit(2); |
1004 | } | |
1005 | ||
1006 | static void | |
fa0f0f45 | 1007 | check_parent_exists(void) |
3c0ef626 | 1008 | { |
3c0ef626 | 1009 | if (parent_pid != -1 && kill(parent_pid, 0) < 0) { |
1010 | /* printf("Parent has died - Authentication agent exiting.\n"); */ | |
fa0f0f45 | 1011 | cleanup_socket(); |
1012 | _exit(2); | |
3c0ef626 | 1013 | } |
3c0ef626 | 1014 | } |
1015 | ||
1016 | static void | |
1017 | usage(void) | |
1018 | { | |
1019 | fprintf(stderr, "Usage: %s [options] [command [args ...]]\n", | |
1020 | __progname); | |
1021 | fprintf(stderr, "Options:\n"); | |
1022 | fprintf(stderr, " -c Generate C-shell commands on stdout.\n"); | |
1023 | fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n"); | |
1024 | fprintf(stderr, " -k Kill the current agent.\n"); | |
1025 | fprintf(stderr, " -d Debug mode.\n"); | |
df84fde0 | 1026 | fprintf(stderr, " -a socket Bind agent socket to given name.\n"); |
bfe49944 | 1027 | fprintf(stderr, " -t life Default identity lifetime (seconds).\n"); |
3c0ef626 | 1028 | exit(1); |
1029 | } | |
1030 | ||
1031 | int | |
1032 | main(int ac, char **av) | |
1033 | { | |
bfe49944 | 1034 | int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0; |
0b90ac93 | 1035 | int sock, fd, ch, result, saved_errno; |
7e82606e | 1036 | u_int nalloc; |
276b07a3 | 1037 | char *shell, *format, *pidstr, *agentsocket = NULL; |
1038 | fd_set *readsetp = NULL, *writesetp = NULL; | |
3c0ef626 | 1039 | struct sockaddr_un sunaddr; |
1040 | #ifdef HAVE_SETRLIMIT | |
1041 | struct rlimit rlim; | |
1042 | #endif | |
3c0ef626 | 1043 | int prev_mask; |
3c0ef626 | 1044 | extern int optind; |
276b07a3 | 1045 | extern char *optarg; |
1046 | pid_t pid; | |
1047 | char pidstrbuf[1 + 3 * sizeof pid]; | |
fa0f0f45 | 1048 | struct timeval *tvp = NULL; |
3c0ef626 | 1049 | |
08822d99 | 1050 | /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */ |
1051 | sanitise_stdfd(); | |
1052 | ||
d03f4262 | 1053 | /* drop */ |
1054 | setegid(getgid()); | |
1055 | setgid(getgid()); | |
1056 | ||
12a403af | 1057 | #if defined(HAVE_PRCTL) && defined(PR_SET_DUMPABLE) |
1058 | /* Disable ptrace on Linux without sgid bit */ | |
1059 | prctl(PR_SET_DUMPABLE, 0); | |
1060 | #endif | |
1061 | ||
3c0ef626 | 1062 | SSLeay_add_all_algorithms(); |
1063 | ||
7cac2b65 | 1064 | __progname = ssh_get_progname(av[0]); |
3c0ef626 | 1065 | init_rng(); |
1066 | seed_rng(); | |
1067 | ||
bfe49944 | 1068 | while ((ch = getopt(ac, av, "cdksa:t:")) != -1) { |
3c0ef626 | 1069 | switch (ch) { |
1070 | case 'c': | |
1071 | if (s_flag) | |
1072 | usage(); | |
1073 | c_flag++; | |
1074 | break; | |
1075 | case 'k': | |
1076 | k_flag++; | |
1077 | break; | |
1078 | case 's': | |
1079 | if (c_flag) | |
1080 | usage(); | |
1081 | s_flag++; | |
1082 | break; | |
1083 | case 'd': | |
1084 | if (d_flag) | |
1085 | usage(); | |
1086 | d_flag++; | |
1087 | break; | |
df84fde0 | 1088 | case 'a': |
1089 | agentsocket = optarg; | |
1090 | break; | |
bfe49944 | 1091 | case 't': |
1092 | if ((lifetime = convtime(optarg)) == -1) { | |
1093 | fprintf(stderr, "Invalid lifetime\n"); | |
1094 | usage(); | |
1095 | } | |
1096 | break; | |
3c0ef626 | 1097 | default: |
1098 | usage(); | |
1099 | } | |
1100 | } | |
1101 | ac -= optind; | |
1102 | av += optind; | |
1103 | ||
1104 | if (ac > 0 && (c_flag || k_flag || s_flag || d_flag)) | |
1105 | usage(); | |
1106 | ||
df84fde0 | 1107 | if (ac == 0 && !c_flag && !s_flag) { |
3c0ef626 | 1108 | shell = getenv("SHELL"); |
30460aeb | 1109 | if (shell != NULL && |
1110 | strncmp(shell + strlen(shell) - 3, "csh", 3) == 0) | |
3c0ef626 | 1111 | c_flag = 1; |
1112 | } | |
1113 | if (k_flag) { | |
30460aeb | 1114 | const char *errstr = NULL; |
1115 | ||
3c0ef626 | 1116 | pidstr = getenv(SSH_AGENTPID_ENV_NAME); |
1117 | if (pidstr == NULL) { | |
1118 | fprintf(stderr, "%s not set, cannot kill agent\n", | |
1119 | SSH_AGENTPID_ENV_NAME); | |
1120 | exit(1); | |
1121 | } | |
30460aeb | 1122 | pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr); |
1123 | if (errstr) { | |
1124 | fprintf(stderr, | |
1125 | "%s=\"%s\", which is not a good PID: %s\n", | |
1126 | SSH_AGENTPID_ENV_NAME, pidstr, errstr); | |
3c0ef626 | 1127 | exit(1); |
1128 | } | |
1129 | if (kill(pid, SIGTERM) == -1) { | |
1130 | perror("kill"); | |
1131 | exit(1); | |
1132 | } | |
1133 | format = c_flag ? "unsetenv %s;\n" : "unset %s;\n"; | |
1134 | printf(format, SSH_AUTHSOCKET_ENV_NAME); | |
1135 | printf(format, SSH_AGENTPID_ENV_NAME); | |
df84fde0 | 1136 | printf("echo Agent pid %ld killed;\n", (long)pid); |
3c0ef626 | 1137 | exit(0); |
1138 | } | |
1139 | parent_pid = getpid(); | |
1140 | ||
df84fde0 | 1141 | if (agentsocket == NULL) { |
1142 | /* Create private directory for agent socket */ | |
540d72c3 | 1143 | strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", sizeof socket_dir); |
df84fde0 | 1144 | if (mkdtemp(socket_dir) == NULL) { |
1145 | perror("mkdtemp: private socket dir"); | |
1146 | exit(1); | |
1147 | } | |
1148 | snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir, | |
1149 | (long)parent_pid); | |
1150 | } else { | |
1151 | /* Try to use specified agent socket */ | |
1152 | socket_dir[0] = '\0'; | |
1153 | strlcpy(socket_name, agentsocket, sizeof socket_name); | |
3c0ef626 | 1154 | } |
3c0ef626 | 1155 | |
1156 | /* | |
1157 | * Create socket early so it will exist before command gets run from | |
1158 | * the parent. | |
1159 | */ | |
1160 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
1161 | if (sock < 0) { | |
1162 | perror("socket"); | |
dfddba3d | 1163 | *socket_name = '\0'; /* Don't unlink any existing file */ |
3c0ef626 | 1164 | cleanup_exit(1); |
1165 | } | |
1166 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
1167 | sunaddr.sun_family = AF_UNIX; | |
1168 | strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path)); | |
3c0ef626 | 1169 | prev_mask = umask(0177); |
30460aeb | 1170 | if (bind(sock, (struct sockaddr *) &sunaddr, sizeof(sunaddr)) < 0) { |
3c0ef626 | 1171 | perror("bind"); |
dfddba3d | 1172 | *socket_name = '\0'; /* Don't unlink any existing file */ |
3c0ef626 | 1173 | umask(prev_mask); |
3c0ef626 | 1174 | cleanup_exit(1); |
1175 | } | |
3c0ef626 | 1176 | umask(prev_mask); |
540d72c3 | 1177 | if (listen(sock, SSH_LISTEN_BACKLOG) < 0) { |
3c0ef626 | 1178 | perror("listen"); |
1179 | cleanup_exit(1); | |
1180 | } | |
1181 | ||
1182 | /* | |
1183 | * Fork, and have the parent execute the command, if any, or present | |
1184 | * the socket data. The child continues as the authentication agent. | |
1185 | */ | |
1186 | if (d_flag) { | |
1187 | log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1); | |
1188 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
1189 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
1190 | SSH_AUTHSOCKET_ENV_NAME); | |
df84fde0 | 1191 | printf("echo Agent pid %ld;\n", (long)parent_pid); |
3c0ef626 | 1192 | goto skip; |
1193 | } | |
1194 | pid = fork(); | |
1195 | if (pid == -1) { | |
1196 | perror("fork"); | |
df84fde0 | 1197 | cleanup_exit(1); |
3c0ef626 | 1198 | } |
1199 | if (pid != 0) { /* Parent - execute the given command. */ | |
1200 | close(sock); | |
df84fde0 | 1201 | snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid); |
3c0ef626 | 1202 | if (ac == 0) { |
1203 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
1204 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
1205 | SSH_AUTHSOCKET_ENV_NAME); | |
1206 | printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, | |
1207 | SSH_AGENTPID_ENV_NAME); | |
df84fde0 | 1208 | printf("echo Agent pid %ld;\n", (long)pid); |
3c0ef626 | 1209 | exit(0); |
1210 | } | |
1211 | if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || | |
1212 | setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { | |
1213 | perror("setenv"); | |
1214 | exit(1); | |
1215 | } | |
1216 | execvp(av[0], av); | |
1217 | perror(av[0]); | |
1218 | exit(1); | |
1219 | } | |
df84fde0 | 1220 | /* child */ |
1221 | log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0); | |
3c0ef626 | 1222 | |
1223 | if (setsid() == -1) { | |
df84fde0 | 1224 | error("setsid: %s", strerror(errno)); |
3c0ef626 | 1225 | cleanup_exit(1); |
1226 | } | |
1227 | ||
1228 | (void)chdir("/"); | |
bfe49944 | 1229 | if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { |
1230 | /* XXX might close listen socket */ | |
1231 | (void)dup2(fd, STDIN_FILENO); | |
1232 | (void)dup2(fd, STDOUT_FILENO); | |
1233 | (void)dup2(fd, STDERR_FILENO); | |
1234 | if (fd > 2) | |
1235 | close(fd); | |
1236 | } | |
3c0ef626 | 1237 | |
1238 | #ifdef HAVE_SETRLIMIT | |
1239 | /* deny core dumps, since memory contains unencrypted private keys */ | |
1240 | rlim.rlim_cur = rlim.rlim_max = 0; | |
1241 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) { | |
df84fde0 | 1242 | error("setrlimit RLIMIT_CORE: %s", strerror(errno)); |
3c0ef626 | 1243 | cleanup_exit(1); |
1244 | } | |
1245 | #endif | |
1246 | ||
1247 | skip: | |
3c0ef626 | 1248 | new_socket(AUTH_SOCKET, sock); |
fa0f0f45 | 1249 | if (ac > 0) |
1250 | parent_alive_interval = 10; | |
3c0ef626 | 1251 | idtab_init(); |
1252 | if (!d_flag) | |
1253 | signal(SIGINT, SIG_IGN); | |
1254 | signal(SIGPIPE, SIG_IGN); | |
1255 | signal(SIGHUP, cleanup_handler); | |
1256 | signal(SIGTERM, cleanup_handler); | |
1257 | nalloc = 0; | |
1258 | ||
1259 | while (1) { | |
fa0f0f45 | 1260 | prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp); |
1261 | result = select(max_fd + 1, readsetp, writesetp, NULL, tvp); | |
0b90ac93 | 1262 | saved_errno = errno; |
fa0f0f45 | 1263 | if (parent_alive_interval != 0) |
1264 | check_parent_exists(); | |
1265 | (void) reaper(); /* remove expired keys */ | |
0b90ac93 | 1266 | if (result < 0) { |
1267 | if (saved_errno == EINTR) | |
3c0ef626 | 1268 | continue; |
0b90ac93 | 1269 | fatal("select: %s", strerror(saved_errno)); |
1270 | } else if (result > 0) | |
1271 | after_select(readsetp, writesetp); | |
3c0ef626 | 1272 | } |
1273 | /* NOTREACHED */ | |
1274 | } |