]>
Commit | Line | Data |
---|---|---|
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 | * The authentication agent program. | |
6 | * | |
7 | * As far as I am concerned, the code I have written for this software | |
8 | * can be used freely for any purpose. Any derived versions of this | |
9 | * software must be clearly marked as such, and if the derived work is | |
10 | * incompatible with the protocol description in the RFC file, it must be | |
11 | * called by a name other than "ssh" or "Secure Shell". | |
12 | * | |
13 | * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved. | |
14 | * | |
15 | * Redistribution and use in source and binary forms, with or without | |
16 | * modification, are permitted provided that the following conditions | |
17 | * are met: | |
18 | * 1. Redistributions of source code must retain the above copyright | |
19 | * notice, this list of conditions and the following disclaimer. | |
20 | * 2. Redistributions in binary form must reproduce the above copyright | |
21 | * notice, this list of conditions and the following disclaimer in the | |
22 | * documentation and/or other materials provided with the distribution. | |
23 | * | |
24 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR | |
25 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES | |
26 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. | |
27 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, | |
28 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT | |
29 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | |
30 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | |
31 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | |
32 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF | |
33 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |
34 | */ | |
35 | ||
36 | #include "includes.h" | |
e9a17296 | 37 | #include "openbsd-compat/fake-queue.h" |
700318f3 | 38 | RCSID("$OpenBSD: ssh-agent.c,v 1.85 2002/04/02 11:49:39 markus Exp $"); |
3c0ef626 | 39 | |
40 | #include <openssl/evp.h> | |
41 | #include <openssl/md5.h> | |
42 | ||
43 | #include "ssh.h" | |
44 | #include "rsa.h" | |
45 | #include "buffer.h" | |
46 | #include "bufaux.h" | |
47 | #include "xmalloc.h" | |
3c0ef626 | 48 | #include "getput.h" |
3c0ef626 | 49 | #include "key.h" |
50 | #include "authfd.h" | |
3c0ef626 | 51 | #include "compat.h" |
52 | #include "log.h" | |
53 | ||
54 | #ifdef SMARTCARD | |
3c0ef626 | 55 | #include "scard.h" |
56 | #endif | |
57 | ||
e9a17296 | 58 | typedef enum { |
59 | AUTH_UNUSED, | |
60 | AUTH_SOCKET, | |
61 | AUTH_CONNECTION | |
62 | } sock_type; | |
63 | ||
3c0ef626 | 64 | typedef struct { |
65 | int fd; | |
e9a17296 | 66 | sock_type type; |
3c0ef626 | 67 | Buffer input; |
68 | Buffer output; | |
69 | } SocketEntry; | |
70 | ||
71 | u_int sockets_alloc = 0; | |
72 | SocketEntry *sockets = NULL; | |
73 | ||
e9a17296 | 74 | typedef struct identity { |
75 | TAILQ_ENTRY(identity) next; | |
3c0ef626 | 76 | Key *key; |
77 | char *comment; | |
78 | } Identity; | |
79 | ||
80 | typedef struct { | |
81 | int nentries; | |
e9a17296 | 82 | TAILQ_HEAD(idqueue, identity) idlist; |
3c0ef626 | 83 | } Idtab; |
84 | ||
85 | /* private key table, one per protocol version */ | |
86 | Idtab idtable[3]; | |
87 | ||
88 | int max_fd = 0; | |
89 | ||
90 | /* pid of shell == parent of agent */ | |
91 | pid_t parent_pid = -1; | |
92 | ||
93 | /* pathname and directory for AUTH_SOCKET */ | |
94 | char socket_name[1024]; | |
95 | char socket_dir[1024]; | |
96 | ||
97 | #ifdef HAVE___PROGNAME | |
98 | extern char *__progname; | |
99 | #else | |
100 | char *__progname; | |
101 | #endif | |
102 | ||
103 | static void | |
104 | idtab_init(void) | |
105 | { | |
106 | int i; | |
e9a17296 | 107 | for (i = 0; i <=2; i++) { |
108 | TAILQ_INIT(&idtable[i].idlist); | |
3c0ef626 | 109 | idtable[i].nentries = 0; |
110 | } | |
111 | } | |
112 | ||
113 | /* return private key table for requested protocol version */ | |
114 | static Idtab * | |
115 | idtab_lookup(int version) | |
116 | { | |
117 | if (version < 1 || version > 2) | |
118 | fatal("internal error, bad protocol version %d", version); | |
119 | return &idtable[version]; | |
120 | } | |
121 | ||
122 | /* return matching private key for given public key */ | |
e9a17296 | 123 | static Identity * |
124 | lookup_identity(Key *key, int version) | |
3c0ef626 | 125 | { |
e9a17296 | 126 | Identity *id; |
127 | ||
3c0ef626 | 128 | Idtab *tab = idtab_lookup(version); |
e9a17296 | 129 | TAILQ_FOREACH(id, &tab->idlist, next) { |
130 | if (key_equal(key, id->key)) | |
131 | return (id); | |
3c0ef626 | 132 | } |
e9a17296 | 133 | return (NULL); |
134 | } | |
135 | ||
136 | static void | |
137 | free_identity(Identity *id) | |
138 | { | |
139 | key_free(id->key); | |
140 | xfree(id->comment); | |
141 | xfree(id); | |
3c0ef626 | 142 | } |
143 | ||
144 | /* send list of supported public keys to 'client' */ | |
145 | static void | |
146 | process_request_identities(SocketEntry *e, int version) | |
147 | { | |
148 | Idtab *tab = idtab_lookup(version); | |
149 | Buffer msg; | |
e9a17296 | 150 | Identity *id; |
3c0ef626 | 151 | |
152 | buffer_init(&msg); | |
153 | buffer_put_char(&msg, (version == 1) ? | |
154 | SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); | |
155 | buffer_put_int(&msg, tab->nentries); | |
e9a17296 | 156 | TAILQ_FOREACH(id, &tab->idlist, next) { |
3c0ef626 | 157 | if (id->key->type == KEY_RSA1) { |
158 | buffer_put_int(&msg, BN_num_bits(id->key->rsa->n)); | |
159 | buffer_put_bignum(&msg, id->key->rsa->e); | |
160 | buffer_put_bignum(&msg, id->key->rsa->n); | |
161 | } else { | |
162 | u_char *blob; | |
163 | u_int blen; | |
164 | key_to_blob(id->key, &blob, &blen); | |
165 | buffer_put_string(&msg, blob, blen); | |
166 | xfree(blob); | |
167 | } | |
168 | buffer_put_cstring(&msg, id->comment); | |
169 | } | |
170 | buffer_put_int(&e->output, buffer_len(&msg)); | |
171 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
172 | buffer_free(&msg); | |
173 | } | |
174 | ||
175 | /* ssh1 only */ | |
176 | static void | |
177 | process_authentication_challenge1(SocketEntry *e) | |
178 | { | |
e9a17296 | 179 | Identity *id; |
180 | Key *key; | |
3c0ef626 | 181 | BIGNUM *challenge; |
182 | int i, len; | |
183 | Buffer msg; | |
184 | MD5_CTX md; | |
185 | u_char buf[32], mdbuf[16], session_id[16]; | |
186 | u_int response_type; | |
187 | ||
188 | buffer_init(&msg); | |
189 | key = key_new(KEY_RSA1); | |
e9a17296 | 190 | if ((challenge = BN_new()) == NULL) |
191 | fatal("process_authentication_challenge1: BN_new failed"); | |
3c0ef626 | 192 | |
193 | buffer_get_int(&e->input); /* ignored */ | |
194 | buffer_get_bignum(&e->input, key->rsa->e); | |
195 | buffer_get_bignum(&e->input, key->rsa->n); | |
196 | buffer_get_bignum(&e->input, challenge); | |
197 | ||
198 | /* Only protocol 1.1 is supported */ | |
199 | if (buffer_len(&e->input) == 0) | |
200 | goto failure; | |
e9a17296 | 201 | buffer_get(&e->input, session_id, 16); |
3c0ef626 | 202 | response_type = buffer_get_int(&e->input); |
203 | if (response_type != 1) | |
204 | goto failure; | |
205 | ||
e9a17296 | 206 | id = lookup_identity(key, 1); |
207 | if (id != NULL) { | |
208 | Key *private = id->key; | |
3c0ef626 | 209 | /* Decrypt the challenge using the private key. */ |
210 | if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0) | |
211 | goto failure; | |
212 | ||
213 | /* The response is MD5 of decrypted challenge plus session id. */ | |
214 | len = BN_num_bytes(challenge); | |
215 | if (len <= 0 || len > 32) { | |
216 | log("process_authentication_challenge: bad challenge length %d", len); | |
217 | goto failure; | |
218 | } | |
219 | memset(buf, 0, 32); | |
220 | BN_bn2bin(challenge, buf + 32 - len); | |
221 | MD5_Init(&md); | |
222 | MD5_Update(&md, buf, 32); | |
223 | MD5_Update(&md, session_id, 16); | |
224 | MD5_Final(mdbuf, &md); | |
225 | ||
226 | /* Send the response. */ | |
227 | buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE); | |
228 | for (i = 0; i < 16; i++) | |
229 | buffer_put_char(&msg, mdbuf[i]); | |
230 | goto send; | |
231 | } | |
232 | ||
233 | failure: | |
234 | /* Unknown identity or protocol error. Send failure. */ | |
235 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
236 | send: | |
237 | buffer_put_int(&e->output, buffer_len(&msg)); | |
238 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
239 | key_free(key); | |
240 | BN_clear_free(challenge); | |
241 | buffer_free(&msg); | |
242 | } | |
243 | ||
244 | /* ssh2 only */ | |
245 | static void | |
246 | process_sign_request2(SocketEntry *e) | |
247 | { | |
248 | extern int datafellows; | |
e9a17296 | 249 | Key *key; |
3c0ef626 | 250 | u_char *blob, *data, *signature = NULL; |
251 | u_int blen, dlen, slen = 0; | |
252 | int flags; | |
253 | Buffer msg; | |
254 | int ok = -1; | |
255 | ||
256 | datafellows = 0; | |
257 | ||
258 | blob = buffer_get_string(&e->input, &blen); | |
259 | data = buffer_get_string(&e->input, &dlen); | |
260 | ||
261 | flags = buffer_get_int(&e->input); | |
262 | if (flags & SSH_AGENT_OLD_SIGNATURE) | |
263 | datafellows = SSH_BUG_SIGBLOB; | |
264 | ||
265 | key = key_from_blob(blob, blen); | |
266 | if (key != NULL) { | |
e9a17296 | 267 | Identity *id = lookup_identity(key, 2); |
268 | if (id != NULL) | |
269 | ok = key_sign(id->key, &signature, &slen, data, dlen); | |
3c0ef626 | 270 | } |
271 | key_free(key); | |
272 | buffer_init(&msg); | |
273 | if (ok == 0) { | |
274 | buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE); | |
275 | buffer_put_string(&msg, signature, slen); | |
276 | } else { | |
277 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
278 | } | |
279 | buffer_put_int(&e->output, buffer_len(&msg)); | |
280 | buffer_append(&e->output, buffer_ptr(&msg), | |
281 | buffer_len(&msg)); | |
282 | buffer_free(&msg); | |
283 | xfree(data); | |
284 | xfree(blob); | |
285 | if (signature != NULL) | |
286 | xfree(signature); | |
287 | } | |
288 | ||
289 | /* shared */ | |
290 | static void | |
291 | process_remove_identity(SocketEntry *e, int version) | |
292 | { | |
e9a17296 | 293 | Key *key = NULL; |
3c0ef626 | 294 | u_char *blob; |
295 | u_int blen; | |
296 | u_int bits; | |
297 | int success = 0; | |
298 | ||
e9a17296 | 299 | switch (version) { |
3c0ef626 | 300 | case 1: |
301 | key = key_new(KEY_RSA1); | |
302 | bits = buffer_get_int(&e->input); | |
303 | buffer_get_bignum(&e->input, key->rsa->e); | |
304 | buffer_get_bignum(&e->input, key->rsa->n); | |
305 | ||
306 | if (bits != key_size(key)) | |
307 | log("Warning: identity keysize mismatch: actual %d, announced %d", | |
308 | key_size(key), bits); | |
309 | break; | |
310 | case 2: | |
311 | blob = buffer_get_string(&e->input, &blen); | |
312 | key = key_from_blob(blob, blen); | |
313 | xfree(blob); | |
314 | break; | |
315 | } | |
316 | if (key != NULL) { | |
e9a17296 | 317 | Identity *id = lookup_identity(key, version); |
318 | if (id != NULL) { | |
3c0ef626 | 319 | /* |
320 | * We have this key. Free the old key. Since we | |
321 | * don\'t want to leave empty slots in the middle of | |
322 | * the array, we actually free the key there and move | |
323 | * all the entries between the empty slot and the end | |
324 | * of the array. | |
325 | */ | |
326 | Idtab *tab = idtab_lookup(version); | |
3c0ef626 | 327 | if (tab->nentries < 1) |
328 | fatal("process_remove_identity: " | |
329 | "internal error: tab->nentries %d", | |
330 | tab->nentries); | |
e9a17296 | 331 | TAILQ_REMOVE(&tab->idlist, id, next); |
332 | free_identity(id); | |
3c0ef626 | 333 | tab->nentries--; |
334 | success = 1; | |
335 | } | |
336 | key_free(key); | |
337 | } | |
338 | buffer_put_int(&e->output, 1); | |
339 | buffer_put_char(&e->output, | |
340 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
341 | } | |
342 | ||
343 | static void | |
344 | process_remove_all_identities(SocketEntry *e, int version) | |
345 | { | |
3c0ef626 | 346 | Idtab *tab = idtab_lookup(version); |
e9a17296 | 347 | Identity *id; |
3c0ef626 | 348 | |
349 | /* Loop over all identities and clear the keys. */ | |
e9a17296 | 350 | for (id = TAILQ_FIRST(&tab->idlist); id; |
351 | id = TAILQ_FIRST(&tab->idlist)) { | |
352 | TAILQ_REMOVE(&tab->idlist, id, next); | |
353 | free_identity(id); | |
3c0ef626 | 354 | } |
355 | ||
356 | /* Mark that there are no identities. */ | |
357 | tab->nentries = 0; | |
358 | ||
359 | /* Send success. */ | |
360 | buffer_put_int(&e->output, 1); | |
361 | buffer_put_char(&e->output, SSH_AGENT_SUCCESS); | |
362 | return; | |
363 | } | |
364 | ||
365 | static void | |
366 | process_add_identity(SocketEntry *e, int version) | |
367 | { | |
368 | Key *k = NULL; | |
369 | char *type_name; | |
370 | char *comment; | |
371 | int type, success = 0; | |
372 | Idtab *tab = idtab_lookup(version); | |
373 | ||
374 | switch (version) { | |
375 | case 1: | |
376 | k = key_new_private(KEY_RSA1); | |
377 | buffer_get_int(&e->input); /* ignored */ | |
378 | buffer_get_bignum(&e->input, k->rsa->n); | |
379 | buffer_get_bignum(&e->input, k->rsa->e); | |
380 | buffer_get_bignum(&e->input, k->rsa->d); | |
381 | buffer_get_bignum(&e->input, k->rsa->iqmp); | |
382 | ||
383 | /* SSH and SSL have p and q swapped */ | |
384 | buffer_get_bignum(&e->input, k->rsa->q); /* p */ | |
385 | buffer_get_bignum(&e->input, k->rsa->p); /* q */ | |
386 | ||
387 | /* Generate additional parameters */ | |
388 | rsa_generate_additional_parameters(k->rsa); | |
389 | break; | |
390 | case 2: | |
391 | type_name = buffer_get_string(&e->input, NULL); | |
392 | type = key_type_from_name(type_name); | |
393 | xfree(type_name); | |
e9a17296 | 394 | switch (type) { |
3c0ef626 | 395 | case KEY_DSA: |
396 | k = key_new_private(type); | |
397 | buffer_get_bignum2(&e->input, k->dsa->p); | |
398 | buffer_get_bignum2(&e->input, k->dsa->q); | |
399 | buffer_get_bignum2(&e->input, k->dsa->g); | |
400 | buffer_get_bignum2(&e->input, k->dsa->pub_key); | |
401 | buffer_get_bignum2(&e->input, k->dsa->priv_key); | |
402 | break; | |
403 | case KEY_RSA: | |
404 | k = key_new_private(type); | |
405 | buffer_get_bignum2(&e->input, k->rsa->n); | |
406 | buffer_get_bignum2(&e->input, k->rsa->e); | |
407 | buffer_get_bignum2(&e->input, k->rsa->d); | |
408 | buffer_get_bignum2(&e->input, k->rsa->iqmp); | |
409 | buffer_get_bignum2(&e->input, k->rsa->p); | |
410 | buffer_get_bignum2(&e->input, k->rsa->q); | |
411 | ||
412 | /* Generate additional parameters */ | |
413 | rsa_generate_additional_parameters(k->rsa); | |
414 | break; | |
415 | default: | |
416 | buffer_clear(&e->input); | |
417 | goto send; | |
418 | } | |
419 | break; | |
420 | } | |
421 | comment = buffer_get_string(&e->input, NULL); | |
422 | if (k == NULL) { | |
423 | xfree(comment); | |
424 | goto send; | |
425 | } | |
426 | success = 1; | |
e9a17296 | 427 | if (lookup_identity(k, version) == NULL) { |
428 | Identity *id = xmalloc(sizeof(Identity)); | |
429 | id->key = k; | |
430 | id->comment = comment; | |
431 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); | |
3c0ef626 | 432 | /* Increment the number of identities. */ |
433 | tab->nentries++; | |
434 | } else { | |
435 | key_free(k); | |
436 | xfree(comment); | |
437 | } | |
438 | send: | |
439 | buffer_put_int(&e->output, 1); | |
440 | buffer_put_char(&e->output, | |
441 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
442 | } | |
443 | ||
444 | ||
445 | #ifdef SMARTCARD | |
446 | static void | |
447 | process_add_smartcard_key (SocketEntry *e) | |
448 | { | |
700318f3 | 449 | Identity *id; |
3c0ef626 | 450 | Idtab *tab; |
700318f3 | 451 | Key **keys, *k; |
452 | char *sc_reader_id = NULL, *pin; | |
453 | int i, version, success = 0; | |
e9a17296 | 454 | |
3c0ef626 | 455 | sc_reader_id = buffer_get_string(&e->input, NULL); |
700318f3 | 456 | pin = buffer_get_string(&e->input, NULL); |
457 | keys = sc_get_keys(sc_reader_id, pin); | |
3c0ef626 | 458 | xfree(sc_reader_id); |
700318f3 | 459 | xfree(pin); |
3c0ef626 | 460 | |
700318f3 | 461 | if (keys == NULL || keys[0] == NULL) { |
462 | error("sc_get_keys failed"); | |
3c0ef626 | 463 | goto send; |
464 | } | |
700318f3 | 465 | for (i = 0; keys[i] != NULL; i++) { |
466 | k = keys[i]; | |
467 | version = k->type == KEY_RSA1 ? 1 : 2; | |
468 | tab = idtab_lookup(version); | |
469 | if (lookup_identity(k, version) == NULL) { | |
470 | id = xmalloc(sizeof(Identity)); | |
471 | id->key = k; | |
472 | id->comment = xstrdup("smartcard key"); | |
473 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); | |
474 | tab->nentries++; | |
475 | success = 1; | |
476 | } else { | |
477 | key_free(k); | |
478 | } | |
479 | keys[i] = NULL; | |
3c0ef626 | 480 | } |
700318f3 | 481 | xfree(keys); |
3c0ef626 | 482 | send: |
483 | buffer_put_int(&e->output, 1); | |
484 | buffer_put_char(&e->output, | |
485 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
486 | } | |
487 | ||
488 | static void | |
489 | process_remove_smartcard_key(SocketEntry *e) | |
490 | { | |
700318f3 | 491 | Identity *id; |
492 | Idtab *tab; | |
493 | Key **keys, *k = NULL; | |
494 | char *sc_reader_id = NULL, *pin; | |
495 | int i, version, success = 0; | |
3c0ef626 | 496 | |
497 | sc_reader_id = buffer_get_string(&e->input, NULL); | |
700318f3 | 498 | pin = buffer_get_string(&e->input, NULL); |
499 | keys = sc_get_keys(sc_reader_id, pin); | |
3c0ef626 | 500 | xfree(sc_reader_id); |
700318f3 | 501 | xfree(pin); |
3c0ef626 | 502 | |
700318f3 | 503 | if (keys == NULL || keys[0] == NULL) { |
504 | error("sc_get_keys failed"); | |
505 | goto send; | |
506 | } | |
507 | for (i = 0; keys[i] != NULL; i++) { | |
508 | k = keys[i]; | |
509 | version = k->type == KEY_RSA1 ? 1 : 2; | |
510 | if ((id = lookup_identity(k, version)) != NULL) { | |
511 | tab = idtab_lookup(version); | |
512 | TAILQ_REMOVE(&tab->idlist, id, next); | |
3c0ef626 | 513 | tab->nentries--; |
e9a17296 | 514 | free_identity(id); |
3c0ef626 | 515 | success = 1; |
516 | } | |
517 | key_free(k); | |
700318f3 | 518 | keys[i] = NULL; |
3c0ef626 | 519 | } |
700318f3 | 520 | xfree(keys); |
521 | send: | |
3c0ef626 | 522 | buffer_put_int(&e->output, 1); |
523 | buffer_put_char(&e->output, | |
524 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
525 | } | |
526 | #endif /* SMARTCARD */ | |
527 | ||
528 | /* dispatch incoming messages */ | |
529 | ||
530 | static void | |
531 | process_message(SocketEntry *e) | |
532 | { | |
533 | u_int msg_len; | |
534 | u_int type; | |
535 | u_char *cp; | |
536 | if (buffer_len(&e->input) < 5) | |
537 | return; /* Incomplete message. */ | |
e9a17296 | 538 | cp = buffer_ptr(&e->input); |
3c0ef626 | 539 | msg_len = GET_32BIT(cp); |
540 | if (msg_len > 256 * 1024) { | |
541 | shutdown(e->fd, SHUT_RDWR); | |
542 | close(e->fd); | |
543 | e->type = AUTH_UNUSED; | |
544 | return; | |
545 | } | |
546 | if (buffer_len(&e->input) < msg_len + 4) | |
547 | return; | |
548 | buffer_consume(&e->input, 4); | |
549 | type = buffer_get_char(&e->input); | |
550 | ||
551 | debug("type %d", type); | |
552 | switch (type) { | |
553 | /* ssh1 */ | |
554 | case SSH_AGENTC_RSA_CHALLENGE: | |
555 | process_authentication_challenge1(e); | |
556 | break; | |
557 | case SSH_AGENTC_REQUEST_RSA_IDENTITIES: | |
558 | process_request_identities(e, 1); | |
559 | break; | |
560 | case SSH_AGENTC_ADD_RSA_IDENTITY: | |
561 | process_add_identity(e, 1); | |
562 | break; | |
563 | case SSH_AGENTC_REMOVE_RSA_IDENTITY: | |
564 | process_remove_identity(e, 1); | |
565 | break; | |
566 | case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: | |
567 | process_remove_all_identities(e, 1); | |
568 | break; | |
569 | /* ssh2 */ | |
570 | case SSH2_AGENTC_SIGN_REQUEST: | |
571 | process_sign_request2(e); | |
572 | break; | |
573 | case SSH2_AGENTC_REQUEST_IDENTITIES: | |
574 | process_request_identities(e, 2); | |
575 | break; | |
576 | case SSH2_AGENTC_ADD_IDENTITY: | |
577 | process_add_identity(e, 2); | |
578 | break; | |
579 | case SSH2_AGENTC_REMOVE_IDENTITY: | |
580 | process_remove_identity(e, 2); | |
581 | break; | |
582 | case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: | |
583 | process_remove_all_identities(e, 2); | |
584 | break; | |
585 | #ifdef SMARTCARD | |
586 | case SSH_AGENTC_ADD_SMARTCARD_KEY: | |
587 | process_add_smartcard_key(e); | |
e9a17296 | 588 | break; |
3c0ef626 | 589 | case SSH_AGENTC_REMOVE_SMARTCARD_KEY: |
590 | process_remove_smartcard_key(e); | |
e9a17296 | 591 | break; |
3c0ef626 | 592 | #endif /* SMARTCARD */ |
593 | default: | |
594 | /* Unknown message. Respond with failure. */ | |
595 | error("Unknown message %d", type); | |
596 | buffer_clear(&e->input); | |
597 | buffer_put_int(&e->output, 1); | |
598 | buffer_put_char(&e->output, SSH_AGENT_FAILURE); | |
599 | break; | |
600 | } | |
601 | } | |
602 | ||
603 | static void | |
e9a17296 | 604 | new_socket(sock_type type, int fd) |
3c0ef626 | 605 | { |
606 | u_int i, old_alloc; | |
607 | if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) | |
608 | error("fcntl O_NONBLOCK: %s", strerror(errno)); | |
609 | ||
610 | if (fd > max_fd) | |
611 | max_fd = fd; | |
612 | ||
613 | for (i = 0; i < sockets_alloc; i++) | |
614 | if (sockets[i].type == AUTH_UNUSED) { | |
615 | sockets[i].fd = fd; | |
616 | sockets[i].type = type; | |
617 | buffer_init(&sockets[i].input); | |
618 | buffer_init(&sockets[i].output); | |
619 | return; | |
620 | } | |
621 | old_alloc = sockets_alloc; | |
622 | sockets_alloc += 10; | |
623 | if (sockets) | |
624 | sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0])); | |
625 | else | |
626 | sockets = xmalloc(sockets_alloc * sizeof(sockets[0])); | |
627 | for (i = old_alloc; i < sockets_alloc; i++) | |
628 | sockets[i].type = AUTH_UNUSED; | |
629 | sockets[old_alloc].type = type; | |
630 | sockets[old_alloc].fd = fd; | |
631 | buffer_init(&sockets[old_alloc].input); | |
632 | buffer_init(&sockets[old_alloc].output); | |
633 | } | |
634 | ||
635 | static int | |
636 | prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp) | |
637 | { | |
638 | u_int i, sz; | |
639 | int n = 0; | |
640 | ||
641 | for (i = 0; i < sockets_alloc; i++) { | |
642 | switch (sockets[i].type) { | |
643 | case AUTH_SOCKET: | |
644 | case AUTH_CONNECTION: | |
645 | n = MAX(n, sockets[i].fd); | |
646 | break; | |
647 | case AUTH_UNUSED: | |
648 | break; | |
649 | default: | |
650 | fatal("Unknown socket type %d", sockets[i].type); | |
651 | break; | |
652 | } | |
653 | } | |
654 | ||
655 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
656 | if (*fdrp == NULL || sz > *nallocp) { | |
657 | if (*fdrp) | |
658 | xfree(*fdrp); | |
659 | if (*fdwp) | |
660 | xfree(*fdwp); | |
661 | *fdrp = xmalloc(sz); | |
662 | *fdwp = xmalloc(sz); | |
663 | *nallocp = sz; | |
664 | } | |
665 | if (n < *fdl) | |
666 | debug("XXX shrink: %d < %d", n, *fdl); | |
667 | *fdl = n; | |
668 | memset(*fdrp, 0, sz); | |
669 | memset(*fdwp, 0, sz); | |
670 | ||
671 | for (i = 0; i < sockets_alloc; i++) { | |
672 | switch (sockets[i].type) { | |
673 | case AUTH_SOCKET: | |
674 | case AUTH_CONNECTION: | |
675 | FD_SET(sockets[i].fd, *fdrp); | |
676 | if (buffer_len(&sockets[i].output) > 0) | |
677 | FD_SET(sockets[i].fd, *fdwp); | |
678 | break; | |
679 | default: | |
680 | break; | |
681 | } | |
682 | } | |
683 | return (1); | |
684 | } | |
685 | ||
686 | static void | |
687 | after_select(fd_set *readset, fd_set *writeset) | |
688 | { | |
689 | u_int i; | |
690 | int len, sock; | |
691 | socklen_t slen; | |
692 | char buf[1024]; | |
693 | struct sockaddr_un sunaddr; | |
694 | ||
695 | for (i = 0; i < sockets_alloc; i++) | |
696 | switch (sockets[i].type) { | |
697 | case AUTH_UNUSED: | |
698 | break; | |
699 | case AUTH_SOCKET: | |
700 | if (FD_ISSET(sockets[i].fd, readset)) { | |
701 | slen = sizeof(sunaddr); | |
702 | sock = accept(sockets[i].fd, | |
703 | (struct sockaddr *) &sunaddr, &slen); | |
704 | if (sock < 0) { | |
e9a17296 | 705 | error("accept from AUTH_SOCKET: %s", |
706 | strerror(errno)); | |
3c0ef626 | 707 | break; |
708 | } | |
709 | new_socket(AUTH_CONNECTION, sock); | |
710 | } | |
711 | break; | |
712 | case AUTH_CONNECTION: | |
713 | if (buffer_len(&sockets[i].output) > 0 && | |
714 | FD_ISSET(sockets[i].fd, writeset)) { | |
715 | do { | |
716 | len = write(sockets[i].fd, | |
717 | buffer_ptr(&sockets[i].output), | |
718 | buffer_len(&sockets[i].output)); | |
719 | if (len == -1 && (errno == EAGAIN || | |
720 | errno == EINTR)) | |
721 | continue; | |
722 | break; | |
723 | } while (1); | |
724 | if (len <= 0) { | |
725 | shutdown(sockets[i].fd, SHUT_RDWR); | |
726 | close(sockets[i].fd); | |
727 | sockets[i].type = AUTH_UNUSED; | |
728 | buffer_free(&sockets[i].input); | |
729 | buffer_free(&sockets[i].output); | |
730 | break; | |
731 | } | |
732 | buffer_consume(&sockets[i].output, len); | |
733 | } | |
734 | if (FD_ISSET(sockets[i].fd, readset)) { | |
735 | do { | |
736 | len = read(sockets[i].fd, buf, sizeof(buf)); | |
737 | if (len == -1 && (errno == EAGAIN || | |
738 | errno == EINTR)) | |
739 | continue; | |
740 | break; | |
741 | } while (1); | |
742 | if (len <= 0) { | |
743 | shutdown(sockets[i].fd, SHUT_RDWR); | |
744 | close(sockets[i].fd); | |
745 | sockets[i].type = AUTH_UNUSED; | |
746 | buffer_free(&sockets[i].input); | |
747 | buffer_free(&sockets[i].output); | |
748 | break; | |
749 | } | |
750 | buffer_append(&sockets[i].input, buf, len); | |
751 | process_message(&sockets[i]); | |
752 | } | |
753 | break; | |
754 | default: | |
755 | fatal("Unknown type %d", sockets[i].type); | |
756 | } | |
757 | } | |
758 | ||
759 | static void | |
e9a17296 | 760 | cleanup_socket(void *p) |
3c0ef626 | 761 | { |
762 | if (socket_name[0]) | |
763 | unlink(socket_name); | |
764 | if (socket_dir[0]) | |
765 | rmdir(socket_dir); | |
766 | } | |
767 | ||
768 | static void | |
769 | cleanup_exit(int i) | |
770 | { | |
e9a17296 | 771 | cleanup_socket(NULL); |
3c0ef626 | 772 | exit(i); |
773 | } | |
774 | ||
775 | static void | |
776 | cleanup_handler(int sig) | |
777 | { | |
e9a17296 | 778 | cleanup_socket(NULL); |
3c0ef626 | 779 | _exit(2); |
780 | } | |
781 | ||
782 | static void | |
783 | check_parent_exists(int sig) | |
784 | { | |
785 | int save_errno = errno; | |
786 | ||
787 | if (parent_pid != -1 && kill(parent_pid, 0) < 0) { | |
788 | /* printf("Parent has died - Authentication agent exiting.\n"); */ | |
789 | cleanup_handler(sig); /* safe */ | |
790 | } | |
791 | signal(SIGALRM, check_parent_exists); | |
792 | alarm(10); | |
793 | errno = save_errno; | |
794 | } | |
795 | ||
796 | static void | |
797 | usage(void) | |
798 | { | |
799 | fprintf(stderr, "Usage: %s [options] [command [args ...]]\n", | |
800 | __progname); | |
801 | fprintf(stderr, "Options:\n"); | |
802 | fprintf(stderr, " -c Generate C-shell commands on stdout.\n"); | |
803 | fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n"); | |
804 | fprintf(stderr, " -k Kill the current agent.\n"); | |
805 | fprintf(stderr, " -d Debug mode.\n"); | |
806 | exit(1); | |
807 | } | |
808 | ||
809 | int | |
810 | main(int ac, char **av) | |
811 | { | |
812 | int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc; | |
813 | struct sockaddr_un sunaddr; | |
814 | #ifdef HAVE_SETRLIMIT | |
815 | struct rlimit rlim; | |
816 | #endif | |
817 | #ifdef HAVE_CYGWIN | |
818 | int prev_mask; | |
819 | #endif | |
820 | pid_t pid; | |
821 | char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid]; | |
822 | extern int optind; | |
823 | fd_set *readsetp = NULL, *writesetp = NULL; | |
824 | ||
825 | SSLeay_add_all_algorithms(); | |
826 | ||
827 | __progname = get_progname(av[0]); | |
828 | init_rng(); | |
829 | seed_rng(); | |
830 | ||
831 | #ifdef __GNU_LIBRARY__ | |
832 | while ((ch = getopt(ac, av, "+cdks")) != -1) { | |
833 | #else /* __GNU_LIBRARY__ */ | |
834 | while ((ch = getopt(ac, av, "cdks")) != -1) { | |
835 | #endif /* __GNU_LIBRARY__ */ | |
836 | switch (ch) { | |
837 | case 'c': | |
838 | if (s_flag) | |
839 | usage(); | |
840 | c_flag++; | |
841 | break; | |
842 | case 'k': | |
843 | k_flag++; | |
844 | break; | |
845 | case 's': | |
846 | if (c_flag) | |
847 | usage(); | |
848 | s_flag++; | |
849 | break; | |
850 | case 'd': | |
851 | if (d_flag) | |
852 | usage(); | |
853 | d_flag++; | |
854 | break; | |
855 | default: | |
856 | usage(); | |
857 | } | |
858 | } | |
859 | ac -= optind; | |
860 | av += optind; | |
861 | ||
862 | if (ac > 0 && (c_flag || k_flag || s_flag || d_flag)) | |
863 | usage(); | |
864 | ||
700318f3 | 865 | if (ac == 0 && !c_flag && !s_flag) { |
3c0ef626 | 866 | shell = getenv("SHELL"); |
867 | if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0) | |
868 | c_flag = 1; | |
869 | } | |
870 | if (k_flag) { | |
871 | pidstr = getenv(SSH_AGENTPID_ENV_NAME); | |
872 | if (pidstr == NULL) { | |
873 | fprintf(stderr, "%s not set, cannot kill agent\n", | |
874 | SSH_AGENTPID_ENV_NAME); | |
875 | exit(1); | |
876 | } | |
877 | pid = atoi(pidstr); | |
878 | if (pid < 1) { | |
879 | fprintf(stderr, "%s=\"%s\", which is not a good PID\n", | |
880 | SSH_AGENTPID_ENV_NAME, pidstr); | |
881 | exit(1); | |
882 | } | |
883 | if (kill(pid, SIGTERM) == -1) { | |
884 | perror("kill"); | |
885 | exit(1); | |
886 | } | |
887 | format = c_flag ? "unsetenv %s;\n" : "unset %s;\n"; | |
888 | printf(format, SSH_AUTHSOCKET_ENV_NAME); | |
889 | printf(format, SSH_AGENTPID_ENV_NAME); | |
890 | printf("echo Agent pid %d killed;\n", pid); | |
891 | exit(0); | |
892 | } | |
893 | parent_pid = getpid(); | |
894 | ||
895 | /* Create private directory for agent socket */ | |
896 | strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir); | |
897 | if (mkdtemp(socket_dir) == NULL) { | |
898 | perror("mkdtemp: private socket dir"); | |
899 | exit(1); | |
900 | } | |
901 | snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir, | |
902 | parent_pid); | |
903 | ||
904 | /* | |
905 | * Create socket early so it will exist before command gets run from | |
906 | * the parent. | |
907 | */ | |
908 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
909 | if (sock < 0) { | |
910 | perror("socket"); | |
911 | cleanup_exit(1); | |
912 | } | |
913 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
914 | sunaddr.sun_family = AF_UNIX; | |
915 | strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path)); | |
916 | #ifdef HAVE_CYGWIN | |
917 | prev_mask = umask(0177); | |
918 | #endif | |
919 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) { | |
920 | perror("bind"); | |
921 | #ifdef HAVE_CYGWIN | |
922 | umask(prev_mask); | |
923 | #endif | |
924 | cleanup_exit(1); | |
925 | } | |
926 | #ifdef HAVE_CYGWIN | |
927 | umask(prev_mask); | |
928 | #endif | |
929 | if (listen(sock, 5) < 0) { | |
930 | perror("listen"); | |
931 | cleanup_exit(1); | |
932 | } | |
933 | ||
934 | /* | |
935 | * Fork, and have the parent execute the command, if any, or present | |
936 | * the socket data. The child continues as the authentication agent. | |
937 | */ | |
938 | if (d_flag) { | |
939 | log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1); | |
940 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
941 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
942 | SSH_AUTHSOCKET_ENV_NAME); | |
943 | printf("echo Agent pid %d;\n", parent_pid); | |
944 | goto skip; | |
945 | } | |
946 | pid = fork(); | |
947 | if (pid == -1) { | |
948 | perror("fork"); | |
e9a17296 | 949 | cleanup_exit(1); |
3c0ef626 | 950 | } |
951 | if (pid != 0) { /* Parent - execute the given command. */ | |
952 | close(sock); | |
953 | snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid); | |
954 | if (ac == 0) { | |
955 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
956 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
957 | SSH_AUTHSOCKET_ENV_NAME); | |
958 | printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, | |
959 | SSH_AGENTPID_ENV_NAME); | |
960 | printf("echo Agent pid %d;\n", pid); | |
961 | exit(0); | |
962 | } | |
963 | if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || | |
964 | setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { | |
965 | perror("setenv"); | |
966 | exit(1); | |
967 | } | |
968 | execvp(av[0], av); | |
969 | perror(av[0]); | |
970 | exit(1); | |
971 | } | |
e9a17296 | 972 | /* child */ |
973 | log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0); | |
3c0ef626 | 974 | |
975 | if (setsid() == -1) { | |
e9a17296 | 976 | error("setsid: %s", strerror(errno)); |
3c0ef626 | 977 | cleanup_exit(1); |
978 | } | |
979 | ||
980 | (void)chdir("/"); | |
981 | close(0); | |
982 | close(1); | |
983 | close(2); | |
984 | ||
985 | #ifdef HAVE_SETRLIMIT | |
986 | /* deny core dumps, since memory contains unencrypted private keys */ | |
987 | rlim.rlim_cur = rlim.rlim_max = 0; | |
988 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) { | |
e9a17296 | 989 | error("setrlimit RLIMIT_CORE: %s", strerror(errno)); |
3c0ef626 | 990 | cleanup_exit(1); |
991 | } | |
992 | #endif | |
993 | ||
994 | skip: | |
e9a17296 | 995 | fatal_add_cleanup(cleanup_socket, NULL); |
3c0ef626 | 996 | new_socket(AUTH_SOCKET, sock); |
997 | if (ac > 0) { | |
998 | signal(SIGALRM, check_parent_exists); | |
999 | alarm(10); | |
1000 | } | |
1001 | idtab_init(); | |
1002 | if (!d_flag) | |
1003 | signal(SIGINT, SIG_IGN); | |
1004 | signal(SIGPIPE, SIG_IGN); | |
1005 | signal(SIGHUP, cleanup_handler); | |
1006 | signal(SIGTERM, cleanup_handler); | |
1007 | nalloc = 0; | |
1008 | ||
1009 | while (1) { | |
1010 | prepare_select(&readsetp, &writesetp, &max_fd, &nalloc); | |
1011 | if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) { | |
1012 | if (errno == EINTR) | |
1013 | continue; | |
e9a17296 | 1014 | fatal("select: %s", strerror(errno)); |
3c0ef626 | 1015 | } |
1016 | after_select(readsetp, writesetp); | |
1017 | } | |
1018 | /* NOTREACHED */ | |
1019 | } |