]>
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" | |
e54b3d7c | 37 | #include "openbsd-compat/sys-queue.h" |
1c14df9e | 38 | RCSID("$OpenBSD: ssh-agent.c,v 1.108 2003/03/13 11:44:50 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" | |
c95ad3d1 | 53 | #include "pathnames.h" |
1c14df9e | 54 | #include "readpass.h" |
55 | #include "misc.h" | |
3c0ef626 | 56 | |
57 | #ifdef SMARTCARD | |
3c0ef626 | 58 | #include "scard.h" |
59 | #endif | |
60 | ||
e9a17296 | 61 | typedef enum { |
62 | AUTH_UNUSED, | |
63 | AUTH_SOCKET, | |
64 | AUTH_CONNECTION | |
65 | } sock_type; | |
66 | ||
3c0ef626 | 67 | typedef struct { |
68 | int fd; | |
e9a17296 | 69 | sock_type type; |
3c0ef626 | 70 | Buffer input; |
71 | Buffer output; | |
ff2d7a98 | 72 | Buffer request; |
3c0ef626 | 73 | } SocketEntry; |
74 | ||
75 | u_int sockets_alloc = 0; | |
76 | SocketEntry *sockets = NULL; | |
77 | ||
e9a17296 | 78 | typedef struct identity { |
79 | TAILQ_ENTRY(identity) next; | |
3c0ef626 | 80 | Key *key; |
81 | char *comment; | |
ff2d7a98 | 82 | u_int death; |
1c14df9e | 83 | u_int confirm; |
3c0ef626 | 84 | } Identity; |
85 | ||
86 | typedef struct { | |
87 | int nentries; | |
e9a17296 | 88 | TAILQ_HEAD(idqueue, identity) idlist; |
3c0ef626 | 89 | } Idtab; |
90 | ||
91 | /* private key table, one per protocol version */ | |
92 | Idtab idtable[3]; | |
93 | ||
94 | int max_fd = 0; | |
95 | ||
96 | /* pid of shell == parent of agent */ | |
97 | pid_t parent_pid = -1; | |
98 | ||
99 | /* pathname and directory for AUTH_SOCKET */ | |
100 | char socket_name[1024]; | |
101 | char socket_dir[1024]; | |
102 | ||
ff2d7a98 | 103 | /* locking */ |
104 | int locked = 0; | |
105 | char *lock_passwd = NULL; | |
106 | ||
3c0ef626 | 107 | #ifdef HAVE___PROGNAME |
108 | extern char *__progname; | |
109 | #else | |
110 | char *__progname; | |
111 | #endif | |
112 | ||
1c14df9e | 113 | /* Default lifetime (0 == forever) */ |
114 | static int lifetime = 0; | |
115 | ||
e54b3d7c | 116 | static void |
117 | close_socket(SocketEntry *e) | |
118 | { | |
119 | close(e->fd); | |
120 | e->fd = -1; | |
121 | e->type = AUTH_UNUSED; | |
122 | buffer_free(&e->input); | |
123 | buffer_free(&e->output); | |
124 | buffer_free(&e->request); | |
125 | } | |
126 | ||
3c0ef626 | 127 | static void |
128 | idtab_init(void) | |
129 | { | |
130 | int i; | |
ff2d7a98 | 131 | |
e9a17296 | 132 | for (i = 0; i <=2; i++) { |
133 | TAILQ_INIT(&idtable[i].idlist); | |
3c0ef626 | 134 | idtable[i].nentries = 0; |
135 | } | |
136 | } | |
137 | ||
138 | /* return private key table for requested protocol version */ | |
139 | static Idtab * | |
140 | idtab_lookup(int version) | |
141 | { | |
142 | if (version < 1 || version > 2) | |
143 | fatal("internal error, bad protocol version %d", version); | |
144 | return &idtable[version]; | |
145 | } | |
146 | ||
ff2d7a98 | 147 | static void |
148 | free_identity(Identity *id) | |
149 | { | |
150 | key_free(id->key); | |
151 | xfree(id->comment); | |
152 | xfree(id); | |
153 | } | |
154 | ||
3c0ef626 | 155 | /* return matching private key for given public key */ |
e9a17296 | 156 | static Identity * |
157 | lookup_identity(Key *key, int version) | |
3c0ef626 | 158 | { |
e9a17296 | 159 | Identity *id; |
160 | ||
3c0ef626 | 161 | Idtab *tab = idtab_lookup(version); |
e9a17296 | 162 | TAILQ_FOREACH(id, &tab->idlist, next) { |
163 | if (key_equal(key, id->key)) | |
164 | return (id); | |
3c0ef626 | 165 | } |
e9a17296 | 166 | return (NULL); |
167 | } | |
168 | ||
1c14df9e | 169 | /* Check confirmation of keysign request */ |
170 | static int | |
171 | confirm_key(Identity *id) | |
172 | { | |
173 | char *p, prompt[1024]; | |
174 | int ret = -1; | |
175 | ||
176 | p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX); | |
177 | snprintf(prompt, sizeof(prompt), "Allow use of key %s?\n" | |
178 | "Key fingerprint %s.", id->comment, p); | |
179 | xfree(p); | |
180 | p = read_passphrase(prompt, RP_ALLOW_EOF); | |
181 | if (p != NULL) { | |
182 | /* | |
183 | * Accept empty responses and responses consisting | |
184 | * of the word "yes" as affirmative. | |
185 | */ | |
186 | if (*p == '\0' || *p == '\n' || strcasecmp(p, "yes") == 0) | |
187 | ret = 0; | |
188 | xfree(p); | |
189 | } | |
190 | return (ret); | |
191 | } | |
192 | ||
3c0ef626 | 193 | /* send list of supported public keys to 'client' */ |
194 | static void | |
195 | process_request_identities(SocketEntry *e, int version) | |
196 | { | |
197 | Idtab *tab = idtab_lookup(version); | |
e9a17296 | 198 | Identity *id; |
ff2d7a98 | 199 | Buffer msg; |
3c0ef626 | 200 | |
201 | buffer_init(&msg); | |
202 | buffer_put_char(&msg, (version == 1) ? | |
203 | SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); | |
204 | buffer_put_int(&msg, tab->nentries); | |
e9a17296 | 205 | TAILQ_FOREACH(id, &tab->idlist, next) { |
3c0ef626 | 206 | if (id->key->type == KEY_RSA1) { |
207 | buffer_put_int(&msg, BN_num_bits(id->key->rsa->n)); | |
208 | buffer_put_bignum(&msg, id->key->rsa->e); | |
209 | buffer_put_bignum(&msg, id->key->rsa->n); | |
210 | } else { | |
211 | u_char *blob; | |
212 | u_int blen; | |
213 | key_to_blob(id->key, &blob, &blen); | |
214 | buffer_put_string(&msg, blob, blen); | |
215 | xfree(blob); | |
216 | } | |
217 | buffer_put_cstring(&msg, id->comment); | |
218 | } | |
219 | buffer_put_int(&e->output, buffer_len(&msg)); | |
220 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
221 | buffer_free(&msg); | |
222 | } | |
223 | ||
224 | /* ssh1 only */ | |
225 | static void | |
226 | process_authentication_challenge1(SocketEntry *e) | |
227 | { | |
ff2d7a98 | 228 | u_char buf[32], mdbuf[16], session_id[16]; |
229 | u_int response_type; | |
3c0ef626 | 230 | BIGNUM *challenge; |
ff2d7a98 | 231 | Identity *id; |
3c0ef626 | 232 | int i, len; |
233 | Buffer msg; | |
234 | MD5_CTX md; | |
ff2d7a98 | 235 | Key *key; |
3c0ef626 | 236 | |
237 | buffer_init(&msg); | |
238 | key = key_new(KEY_RSA1); | |
e9a17296 | 239 | if ((challenge = BN_new()) == NULL) |
240 | fatal("process_authentication_challenge1: BN_new failed"); | |
3c0ef626 | 241 | |
ff2d7a98 | 242 | (void) buffer_get_int(&e->request); /* ignored */ |
243 | buffer_get_bignum(&e->request, key->rsa->e); | |
244 | buffer_get_bignum(&e->request, key->rsa->n); | |
245 | buffer_get_bignum(&e->request, challenge); | |
3c0ef626 | 246 | |
247 | /* Only protocol 1.1 is supported */ | |
ff2d7a98 | 248 | if (buffer_len(&e->request) == 0) |
3c0ef626 | 249 | goto failure; |
ff2d7a98 | 250 | buffer_get(&e->request, session_id, 16); |
251 | response_type = buffer_get_int(&e->request); | |
3c0ef626 | 252 | if (response_type != 1) |
253 | goto failure; | |
254 | ||
e9a17296 | 255 | id = lookup_identity(key, 1); |
1c14df9e | 256 | if (id != NULL && (!id->confirm || confirm_key(id) == 0)) { |
e9a17296 | 257 | Key *private = id->key; |
3c0ef626 | 258 | /* Decrypt the challenge using the private key. */ |
259 | if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0) | |
260 | goto failure; | |
261 | ||
262 | /* The response is MD5 of decrypted challenge plus session id. */ | |
263 | len = BN_num_bytes(challenge); | |
264 | if (len <= 0 || len > 32) { | |
265 | log("process_authentication_challenge: bad challenge length %d", len); | |
266 | goto failure; | |
267 | } | |
268 | memset(buf, 0, 32); | |
269 | BN_bn2bin(challenge, buf + 32 - len); | |
270 | MD5_Init(&md); | |
271 | MD5_Update(&md, buf, 32); | |
272 | MD5_Update(&md, session_id, 16); | |
273 | MD5_Final(mdbuf, &md); | |
274 | ||
275 | /* Send the response. */ | |
276 | buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE); | |
277 | for (i = 0; i < 16; i++) | |
278 | buffer_put_char(&msg, mdbuf[i]); | |
279 | goto send; | |
280 | } | |
281 | ||
282 | failure: | |
283 | /* Unknown identity or protocol error. Send failure. */ | |
284 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
285 | send: | |
286 | buffer_put_int(&e->output, buffer_len(&msg)); | |
287 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
288 | key_free(key); | |
289 | BN_clear_free(challenge); | |
290 | buffer_free(&msg); | |
291 | } | |
292 | ||
293 | /* ssh2 only */ | |
294 | static void | |
295 | process_sign_request2(SocketEntry *e) | |
296 | { | |
3c0ef626 | 297 | u_char *blob, *data, *signature = NULL; |
298 | u_int blen, dlen, slen = 0; | |
ff2d7a98 | 299 | extern int datafellows; |
300 | int ok = -1, flags; | |
3c0ef626 | 301 | Buffer msg; |
ff2d7a98 | 302 | Key *key; |
3c0ef626 | 303 | |
304 | datafellows = 0; | |
305 | ||
ff2d7a98 | 306 | blob = buffer_get_string(&e->request, &blen); |
307 | data = buffer_get_string(&e->request, &dlen); | |
3c0ef626 | 308 | |
ff2d7a98 | 309 | flags = buffer_get_int(&e->request); |
3c0ef626 | 310 | if (flags & SSH_AGENT_OLD_SIGNATURE) |
311 | datafellows = SSH_BUG_SIGBLOB; | |
312 | ||
313 | key = key_from_blob(blob, blen); | |
314 | if (key != NULL) { | |
e9a17296 | 315 | Identity *id = lookup_identity(key, 2); |
1c14df9e | 316 | if (id != NULL && (!id->confirm || confirm_key(id) == 0)) |
e9a17296 | 317 | ok = key_sign(id->key, &signature, &slen, data, dlen); |
3c0ef626 | 318 | } |
319 | key_free(key); | |
320 | buffer_init(&msg); | |
321 | if (ok == 0) { | |
322 | buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE); | |
323 | buffer_put_string(&msg, signature, slen); | |
324 | } else { | |
325 | buffer_put_char(&msg, SSH_AGENT_FAILURE); | |
326 | } | |
327 | buffer_put_int(&e->output, buffer_len(&msg)); | |
328 | buffer_append(&e->output, buffer_ptr(&msg), | |
329 | buffer_len(&msg)); | |
330 | buffer_free(&msg); | |
331 | xfree(data); | |
332 | xfree(blob); | |
333 | if (signature != NULL) | |
334 | xfree(signature); | |
335 | } | |
336 | ||
337 | /* shared */ | |
338 | static void | |
339 | process_remove_identity(SocketEntry *e, int version) | |
340 | { | |
ff2d7a98 | 341 | u_int blen, bits; |
342 | int success = 0; | |
e9a17296 | 343 | Key *key = NULL; |
3c0ef626 | 344 | u_char *blob; |
3c0ef626 | 345 | |
e9a17296 | 346 | switch (version) { |
3c0ef626 | 347 | case 1: |
348 | key = key_new(KEY_RSA1); | |
ff2d7a98 | 349 | bits = buffer_get_int(&e->request); |
350 | buffer_get_bignum(&e->request, key->rsa->e); | |
351 | buffer_get_bignum(&e->request, key->rsa->n); | |
3c0ef626 | 352 | |
353 | if (bits != key_size(key)) | |
ff2d7a98 | 354 | log("Warning: identity keysize mismatch: actual %u, announced %u", |
3c0ef626 | 355 | key_size(key), bits); |
356 | break; | |
357 | case 2: | |
ff2d7a98 | 358 | blob = buffer_get_string(&e->request, &blen); |
3c0ef626 | 359 | key = key_from_blob(blob, blen); |
360 | xfree(blob); | |
361 | break; | |
362 | } | |
363 | if (key != NULL) { | |
e9a17296 | 364 | Identity *id = lookup_identity(key, version); |
365 | if (id != NULL) { | |
3c0ef626 | 366 | /* |
367 | * We have this key. Free the old key. Since we | |
368 | * don\'t want to leave empty slots in the middle of | |
369 | * the array, we actually free the key there and move | |
370 | * all the entries between the empty slot and the end | |
371 | * of the array. | |
372 | */ | |
373 | Idtab *tab = idtab_lookup(version); | |
3c0ef626 | 374 | if (tab->nentries < 1) |
375 | fatal("process_remove_identity: " | |
376 | "internal error: tab->nentries %d", | |
377 | tab->nentries); | |
e9a17296 | 378 | TAILQ_REMOVE(&tab->idlist, id, next); |
379 | free_identity(id); | |
3c0ef626 | 380 | tab->nentries--; |
381 | success = 1; | |
382 | } | |
383 | key_free(key); | |
384 | } | |
385 | buffer_put_int(&e->output, 1); | |
386 | buffer_put_char(&e->output, | |
387 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
388 | } | |
389 | ||
390 | static void | |
391 | process_remove_all_identities(SocketEntry *e, int version) | |
392 | { | |
3c0ef626 | 393 | Idtab *tab = idtab_lookup(version); |
e9a17296 | 394 | Identity *id; |
3c0ef626 | 395 | |
396 | /* Loop over all identities and clear the keys. */ | |
e9a17296 | 397 | for (id = TAILQ_FIRST(&tab->idlist); id; |
398 | id = TAILQ_FIRST(&tab->idlist)) { | |
399 | TAILQ_REMOVE(&tab->idlist, id, next); | |
400 | free_identity(id); | |
3c0ef626 | 401 | } |
402 | ||
403 | /* Mark that there are no identities. */ | |
404 | tab->nentries = 0; | |
405 | ||
406 | /* Send success. */ | |
407 | buffer_put_int(&e->output, 1); | |
408 | buffer_put_char(&e->output, SSH_AGENT_SUCCESS); | |
ff2d7a98 | 409 | } |
410 | ||
411 | static void | |
412 | reaper(void) | |
413 | { | |
414 | u_int now = time(NULL); | |
415 | Identity *id, *nxt; | |
416 | int version; | |
417 | Idtab *tab; | |
418 | ||
419 | for (version = 1; version < 3; version++) { | |
420 | tab = idtab_lookup(version); | |
421 | for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) { | |
422 | nxt = TAILQ_NEXT(id, next); | |
423 | if (id->death != 0 && now >= id->death) { | |
424 | TAILQ_REMOVE(&tab->idlist, id, next); | |
425 | free_identity(id); | |
426 | tab->nentries--; | |
427 | } | |
428 | } | |
429 | } | |
3c0ef626 | 430 | } |
431 | ||
432 | static void | |
433 | process_add_identity(SocketEntry *e, int version) | |
434 | { | |
3c0ef626 | 435 | Idtab *tab = idtab_lookup(version); |
1c14df9e | 436 | int type, success = 0, death = 0, confirm = 0; |
ff2d7a98 | 437 | char *type_name, *comment; |
438 | Key *k = NULL; | |
3c0ef626 | 439 | |
440 | switch (version) { | |
441 | case 1: | |
442 | k = key_new_private(KEY_RSA1); | |
ff2d7a98 | 443 | (void) buffer_get_int(&e->request); /* ignored */ |
444 | buffer_get_bignum(&e->request, k->rsa->n); | |
445 | buffer_get_bignum(&e->request, k->rsa->e); | |
446 | buffer_get_bignum(&e->request, k->rsa->d); | |
447 | buffer_get_bignum(&e->request, k->rsa->iqmp); | |
3c0ef626 | 448 | |
449 | /* SSH and SSL have p and q swapped */ | |
ff2d7a98 | 450 | buffer_get_bignum(&e->request, k->rsa->q); /* p */ |
451 | buffer_get_bignum(&e->request, k->rsa->p); /* q */ | |
3c0ef626 | 452 | |
453 | /* Generate additional parameters */ | |
454 | rsa_generate_additional_parameters(k->rsa); | |
455 | break; | |
456 | case 2: | |
ff2d7a98 | 457 | type_name = buffer_get_string(&e->request, NULL); |
3c0ef626 | 458 | type = key_type_from_name(type_name); |
459 | xfree(type_name); | |
e9a17296 | 460 | switch (type) { |
3c0ef626 | 461 | case KEY_DSA: |
462 | k = key_new_private(type); | |
ff2d7a98 | 463 | buffer_get_bignum2(&e->request, k->dsa->p); |
464 | buffer_get_bignum2(&e->request, k->dsa->q); | |
465 | buffer_get_bignum2(&e->request, k->dsa->g); | |
466 | buffer_get_bignum2(&e->request, k->dsa->pub_key); | |
467 | buffer_get_bignum2(&e->request, k->dsa->priv_key); | |
3c0ef626 | 468 | break; |
469 | case KEY_RSA: | |
470 | k = key_new_private(type); | |
ff2d7a98 | 471 | buffer_get_bignum2(&e->request, k->rsa->n); |
472 | buffer_get_bignum2(&e->request, k->rsa->e); | |
473 | buffer_get_bignum2(&e->request, k->rsa->d); | |
474 | buffer_get_bignum2(&e->request, k->rsa->iqmp); | |
475 | buffer_get_bignum2(&e->request, k->rsa->p); | |
476 | buffer_get_bignum2(&e->request, k->rsa->q); | |
3c0ef626 | 477 | |
478 | /* Generate additional parameters */ | |
479 | rsa_generate_additional_parameters(k->rsa); | |
480 | break; | |
481 | default: | |
ff2d7a98 | 482 | buffer_clear(&e->request); |
3c0ef626 | 483 | goto send; |
484 | } | |
485 | break; | |
486 | } | |
1c14df9e | 487 | /* enable blinding */ |
488 | switch (k->type) { | |
489 | case KEY_RSA: | |
490 | case KEY_RSA1: | |
491 | if (RSA_blinding_on(k->rsa, NULL) != 1) { | |
492 | error("process_add_identity: RSA_blinding_on failed"); | |
493 | key_free(k); | |
494 | goto send; | |
495 | } | |
496 | break; | |
497 | } | |
ff2d7a98 | 498 | comment = buffer_get_string(&e->request, NULL); |
3c0ef626 | 499 | if (k == NULL) { |
500 | xfree(comment); | |
501 | goto send; | |
502 | } | |
503 | success = 1; | |
ff2d7a98 | 504 | while (buffer_len(&e->request)) { |
505 | switch (buffer_get_char(&e->request)) { | |
506 | case SSH_AGENT_CONSTRAIN_LIFETIME: | |
507 | death = time(NULL) + buffer_get_int(&e->request); | |
508 | break; | |
1c14df9e | 509 | case SSH_AGENT_CONSTRAIN_CONFIRM: |
510 | confirm = 1; | |
511 | break; | |
ff2d7a98 | 512 | default: |
513 | break; | |
514 | } | |
515 | } | |
1c14df9e | 516 | if (lifetime && !death) |
517 | death = time(NULL) + lifetime; | |
e9a17296 | 518 | if (lookup_identity(k, version) == NULL) { |
519 | Identity *id = xmalloc(sizeof(Identity)); | |
520 | id->key = k; | |
521 | id->comment = comment; | |
ff2d7a98 | 522 | id->death = death; |
1c14df9e | 523 | id->confirm = confirm; |
e9a17296 | 524 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); |
3c0ef626 | 525 | /* Increment the number of identities. */ |
526 | tab->nentries++; | |
527 | } else { | |
528 | key_free(k); | |
529 | xfree(comment); | |
530 | } | |
531 | send: | |
532 | buffer_put_int(&e->output, 1); | |
533 | buffer_put_char(&e->output, | |
534 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
535 | } | |
536 | ||
ff2d7a98 | 537 | /* XXX todo: encrypt sensitive data with passphrase */ |
538 | static void | |
539 | process_lock_agent(SocketEntry *e, int lock) | |
540 | { | |
541 | int success = 0; | |
542 | char *passwd; | |
543 | ||
544 | passwd = buffer_get_string(&e->request, NULL); | |
545 | if (locked && !lock && strcmp(passwd, lock_passwd) == 0) { | |
546 | locked = 0; | |
547 | memset(lock_passwd, 0, strlen(lock_passwd)); | |
548 | xfree(lock_passwd); | |
549 | lock_passwd = NULL; | |
550 | success = 1; | |
551 | } else if (!locked && lock) { | |
552 | locked = 1; | |
553 | lock_passwd = xstrdup(passwd); | |
554 | success = 1; | |
555 | } | |
556 | memset(passwd, 0, strlen(passwd)); | |
557 | xfree(passwd); | |
558 | ||
559 | buffer_put_int(&e->output, 1); | |
560 | buffer_put_char(&e->output, | |
561 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
562 | } | |
563 | ||
564 | static void | |
565 | no_identities(SocketEntry *e, u_int type) | |
566 | { | |
567 | Buffer msg; | |
568 | ||
569 | buffer_init(&msg); | |
570 | buffer_put_char(&msg, | |
571 | (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ? | |
572 | SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER); | |
573 | buffer_put_int(&msg, 0); | |
574 | buffer_put_int(&e->output, buffer_len(&msg)); | |
575 | buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg)); | |
576 | buffer_free(&msg); | |
577 | } | |
3c0ef626 | 578 | |
579 | #ifdef SMARTCARD | |
580 | static void | |
581 | process_add_smartcard_key (SocketEntry *e) | |
582 | { | |
2980ea68 | 583 | char *sc_reader_id = NULL, *pin; |
584 | int i, version, success = 0; | |
ff2d7a98 | 585 | Key **keys, *k; |
586 | Identity *id; | |
587 | Idtab *tab; | |
e9a17296 | 588 | |
ff2d7a98 | 589 | sc_reader_id = buffer_get_string(&e->request, NULL); |
590 | pin = buffer_get_string(&e->request, NULL); | |
2980ea68 | 591 | keys = sc_get_keys(sc_reader_id, pin); |
3c0ef626 | 592 | xfree(sc_reader_id); |
2980ea68 | 593 | xfree(pin); |
3c0ef626 | 594 | |
2980ea68 | 595 | if (keys == NULL || keys[0] == NULL) { |
596 | error("sc_get_keys failed"); | |
3c0ef626 | 597 | goto send; |
598 | } | |
2980ea68 | 599 | for (i = 0; keys[i] != NULL; i++) { |
600 | k = keys[i]; | |
601 | version = k->type == KEY_RSA1 ? 1 : 2; | |
602 | tab = idtab_lookup(version); | |
603 | if (lookup_identity(k, version) == NULL) { | |
604 | id = xmalloc(sizeof(Identity)); | |
605 | id->key = k; | |
606 | id->comment = xstrdup("smartcard key"); | |
ff2d7a98 | 607 | id->death = 0; |
1c14df9e | 608 | id->confirm = 0; |
2980ea68 | 609 | TAILQ_INSERT_TAIL(&tab->idlist, id, next); |
610 | tab->nentries++; | |
611 | success = 1; | |
612 | } else { | |
613 | key_free(k); | |
614 | } | |
615 | keys[i] = NULL; | |
3c0ef626 | 616 | } |
2980ea68 | 617 | xfree(keys); |
3c0ef626 | 618 | send: |
619 | buffer_put_int(&e->output, 1); | |
620 | buffer_put_char(&e->output, | |
621 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
622 | } | |
623 | ||
624 | static void | |
625 | process_remove_smartcard_key(SocketEntry *e) | |
626 | { | |
2980ea68 | 627 | char *sc_reader_id = NULL, *pin; |
628 | int i, version, success = 0; | |
ff2d7a98 | 629 | Key **keys, *k = NULL; |
630 | Identity *id; | |
631 | Idtab *tab; | |
3c0ef626 | 632 | |
ff2d7a98 | 633 | sc_reader_id = buffer_get_string(&e->request, NULL); |
634 | pin = buffer_get_string(&e->request, NULL); | |
2980ea68 | 635 | keys = sc_get_keys(sc_reader_id, pin); |
3c0ef626 | 636 | xfree(sc_reader_id); |
2980ea68 | 637 | xfree(pin); |
3c0ef626 | 638 | |
2980ea68 | 639 | if (keys == NULL || keys[0] == NULL) { |
640 | error("sc_get_keys failed"); | |
641 | goto send; | |
642 | } | |
643 | for (i = 0; keys[i] != NULL; i++) { | |
644 | k = keys[i]; | |
645 | version = k->type == KEY_RSA1 ? 1 : 2; | |
646 | if ((id = lookup_identity(k, version)) != NULL) { | |
647 | tab = idtab_lookup(version); | |
ff2d7a98 | 648 | TAILQ_REMOVE(&tab->idlist, id, next); |
3c0ef626 | 649 | tab->nentries--; |
e9a17296 | 650 | free_identity(id); |
3c0ef626 | 651 | success = 1; |
652 | } | |
653 | key_free(k); | |
2980ea68 | 654 | keys[i] = NULL; |
3c0ef626 | 655 | } |
2980ea68 | 656 | xfree(keys); |
657 | send: | |
3c0ef626 | 658 | buffer_put_int(&e->output, 1); |
659 | buffer_put_char(&e->output, | |
660 | success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE); | |
661 | } | |
662 | #endif /* SMARTCARD */ | |
663 | ||
664 | /* dispatch incoming messages */ | |
665 | ||
666 | static void | |
667 | process_message(SocketEntry *e) | |
668 | { | |
ff2d7a98 | 669 | u_int msg_len, type; |
3c0ef626 | 670 | u_char *cp; |
ff2d7a98 | 671 | |
672 | /* kill dead keys */ | |
673 | reaper(); | |
674 | ||
3c0ef626 | 675 | if (buffer_len(&e->input) < 5) |
676 | return; /* Incomplete message. */ | |
e9a17296 | 677 | cp = buffer_ptr(&e->input); |
3c0ef626 | 678 | msg_len = GET_32BIT(cp); |
679 | if (msg_len > 256 * 1024) { | |
e54b3d7c | 680 | close_socket(e); |
3c0ef626 | 681 | return; |
682 | } | |
683 | if (buffer_len(&e->input) < msg_len + 4) | |
684 | return; | |
ff2d7a98 | 685 | |
686 | /* move the current input to e->request */ | |
3c0ef626 | 687 | buffer_consume(&e->input, 4); |
ff2d7a98 | 688 | buffer_clear(&e->request); |
689 | buffer_append(&e->request, buffer_ptr(&e->input), msg_len); | |
690 | buffer_consume(&e->input, msg_len); | |
691 | type = buffer_get_char(&e->request); | |
692 | ||
693 | /* check wheter agent is locked */ | |
694 | if (locked && type != SSH_AGENTC_UNLOCK) { | |
695 | buffer_clear(&e->request); | |
696 | switch (type) { | |
697 | case SSH_AGENTC_REQUEST_RSA_IDENTITIES: | |
698 | case SSH2_AGENTC_REQUEST_IDENTITIES: | |
699 | /* send empty lists */ | |
700 | no_identities(e, type); | |
701 | break; | |
702 | default: | |
703 | /* send a fail message for all other request types */ | |
704 | buffer_put_int(&e->output, 1); | |
705 | buffer_put_char(&e->output, SSH_AGENT_FAILURE); | |
706 | } | |
707 | return; | |
708 | } | |
3c0ef626 | 709 | |
710 | debug("type %d", type); | |
711 | switch (type) { | |
ff2d7a98 | 712 | case SSH_AGENTC_LOCK: |
713 | case SSH_AGENTC_UNLOCK: | |
714 | process_lock_agent(e, type == SSH_AGENTC_LOCK); | |
715 | break; | |
3c0ef626 | 716 | /* ssh1 */ |
717 | case SSH_AGENTC_RSA_CHALLENGE: | |
718 | process_authentication_challenge1(e); | |
719 | break; | |
720 | case SSH_AGENTC_REQUEST_RSA_IDENTITIES: | |
721 | process_request_identities(e, 1); | |
722 | break; | |
723 | case SSH_AGENTC_ADD_RSA_IDENTITY: | |
ff2d7a98 | 724 | case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED: |
3c0ef626 | 725 | process_add_identity(e, 1); |
726 | break; | |
727 | case SSH_AGENTC_REMOVE_RSA_IDENTITY: | |
728 | process_remove_identity(e, 1); | |
729 | break; | |
730 | case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES: | |
731 | process_remove_all_identities(e, 1); | |
732 | break; | |
733 | /* ssh2 */ | |
734 | case SSH2_AGENTC_SIGN_REQUEST: | |
735 | process_sign_request2(e); | |
736 | break; | |
737 | case SSH2_AGENTC_REQUEST_IDENTITIES: | |
738 | process_request_identities(e, 2); | |
739 | break; | |
740 | case SSH2_AGENTC_ADD_IDENTITY: | |
ff2d7a98 | 741 | case SSH2_AGENTC_ADD_ID_CONSTRAINED: |
3c0ef626 | 742 | process_add_identity(e, 2); |
743 | break; | |
744 | case SSH2_AGENTC_REMOVE_IDENTITY: | |
745 | process_remove_identity(e, 2); | |
746 | break; | |
747 | case SSH2_AGENTC_REMOVE_ALL_IDENTITIES: | |
748 | process_remove_all_identities(e, 2); | |
749 | break; | |
750 | #ifdef SMARTCARD | |
751 | case SSH_AGENTC_ADD_SMARTCARD_KEY: | |
752 | process_add_smartcard_key(e); | |
e9a17296 | 753 | break; |
3c0ef626 | 754 | case SSH_AGENTC_REMOVE_SMARTCARD_KEY: |
755 | process_remove_smartcard_key(e); | |
e9a17296 | 756 | break; |
3c0ef626 | 757 | #endif /* SMARTCARD */ |
758 | default: | |
759 | /* Unknown message. Respond with failure. */ | |
760 | error("Unknown message %d", type); | |
ff2d7a98 | 761 | buffer_clear(&e->request); |
3c0ef626 | 762 | buffer_put_int(&e->output, 1); |
763 | buffer_put_char(&e->output, SSH_AGENT_FAILURE); | |
764 | break; | |
765 | } | |
766 | } | |
767 | ||
768 | static void | |
e9a17296 | 769 | new_socket(sock_type type, int fd) |
3c0ef626 | 770 | { |
771 | u_int i, old_alloc; | |
ff2d7a98 | 772 | |
3c0ef626 | 773 | if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0) |
774 | error("fcntl O_NONBLOCK: %s", strerror(errno)); | |
775 | ||
776 | if (fd > max_fd) | |
777 | max_fd = fd; | |
778 | ||
779 | for (i = 0; i < sockets_alloc; i++) | |
780 | if (sockets[i].type == AUTH_UNUSED) { | |
781 | sockets[i].fd = fd; | |
782 | sockets[i].type = type; | |
783 | buffer_init(&sockets[i].input); | |
784 | buffer_init(&sockets[i].output); | |
ff2d7a98 | 785 | buffer_init(&sockets[i].request); |
3c0ef626 | 786 | return; |
787 | } | |
788 | old_alloc = sockets_alloc; | |
789 | sockets_alloc += 10; | |
790 | if (sockets) | |
791 | sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0])); | |
792 | else | |
793 | sockets = xmalloc(sockets_alloc * sizeof(sockets[0])); | |
794 | for (i = old_alloc; i < sockets_alloc; i++) | |
795 | sockets[i].type = AUTH_UNUSED; | |
796 | sockets[old_alloc].type = type; | |
797 | sockets[old_alloc].fd = fd; | |
798 | buffer_init(&sockets[old_alloc].input); | |
799 | buffer_init(&sockets[old_alloc].output); | |
ff2d7a98 | 800 | buffer_init(&sockets[old_alloc].request); |
3c0ef626 | 801 | } |
802 | ||
803 | static int | |
804 | prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp) | |
805 | { | |
806 | u_int i, sz; | |
807 | int n = 0; | |
808 | ||
809 | for (i = 0; i < sockets_alloc; i++) { | |
810 | switch (sockets[i].type) { | |
811 | case AUTH_SOCKET: | |
812 | case AUTH_CONNECTION: | |
813 | n = MAX(n, sockets[i].fd); | |
814 | break; | |
815 | case AUTH_UNUSED: | |
816 | break; | |
817 | default: | |
818 | fatal("Unknown socket type %d", sockets[i].type); | |
819 | break; | |
820 | } | |
821 | } | |
822 | ||
823 | sz = howmany(n+1, NFDBITS) * sizeof(fd_mask); | |
824 | if (*fdrp == NULL || sz > *nallocp) { | |
825 | if (*fdrp) | |
826 | xfree(*fdrp); | |
827 | if (*fdwp) | |
828 | xfree(*fdwp); | |
829 | *fdrp = xmalloc(sz); | |
830 | *fdwp = xmalloc(sz); | |
831 | *nallocp = sz; | |
832 | } | |
833 | if (n < *fdl) | |
834 | debug("XXX shrink: %d < %d", n, *fdl); | |
835 | *fdl = n; | |
836 | memset(*fdrp, 0, sz); | |
837 | memset(*fdwp, 0, sz); | |
838 | ||
839 | for (i = 0; i < sockets_alloc; i++) { | |
840 | switch (sockets[i].type) { | |
841 | case AUTH_SOCKET: | |
842 | case AUTH_CONNECTION: | |
843 | FD_SET(sockets[i].fd, *fdrp); | |
844 | if (buffer_len(&sockets[i].output) > 0) | |
845 | FD_SET(sockets[i].fd, *fdwp); | |
846 | break; | |
847 | default: | |
848 | break; | |
849 | } | |
850 | } | |
851 | return (1); | |
852 | } | |
853 | ||
854 | static void | |
855 | after_select(fd_set *readset, fd_set *writeset) | |
856 | { | |
ff2d7a98 | 857 | struct sockaddr_un sunaddr; |
3c0ef626 | 858 | socklen_t slen; |
859 | char buf[1024]; | |
ff2d7a98 | 860 | int len, sock; |
861 | u_int i; | |
e54b3d7c | 862 | uid_t euid; |
863 | gid_t egid; | |
3c0ef626 | 864 | |
865 | for (i = 0; i < sockets_alloc; i++) | |
866 | switch (sockets[i].type) { | |
867 | case AUTH_UNUSED: | |
868 | break; | |
869 | case AUTH_SOCKET: | |
870 | if (FD_ISSET(sockets[i].fd, readset)) { | |
871 | slen = sizeof(sunaddr); | |
872 | sock = accept(sockets[i].fd, | |
873 | (struct sockaddr *) &sunaddr, &slen); | |
874 | if (sock < 0) { | |
e9a17296 | 875 | error("accept from AUTH_SOCKET: %s", |
876 | strerror(errno)); | |
3c0ef626 | 877 | break; |
878 | } | |
e54b3d7c | 879 | if (getpeereid(sock, &euid, &egid) < 0) { |
880 | error("getpeereid %d failed: %s", | |
881 | sock, strerror(errno)); | |
882 | close(sock); | |
883 | break; | |
884 | } | |
885 | if ((euid != 0) && (getuid() != euid)) { | |
886 | error("uid mismatch: " | |
887 | "peer euid %u != uid %u", | |
888 | (u_int) euid, (u_int) getuid()); | |
889 | close(sock); | |
890 | break; | |
891 | } | |
3c0ef626 | 892 | new_socket(AUTH_CONNECTION, sock); |
893 | } | |
894 | break; | |
895 | case AUTH_CONNECTION: | |
896 | if (buffer_len(&sockets[i].output) > 0 && | |
897 | FD_ISSET(sockets[i].fd, writeset)) { | |
898 | do { | |
899 | len = write(sockets[i].fd, | |
900 | buffer_ptr(&sockets[i].output), | |
901 | buffer_len(&sockets[i].output)); | |
902 | if (len == -1 && (errno == EAGAIN || | |
903 | errno == EINTR)) | |
904 | continue; | |
905 | break; | |
906 | } while (1); | |
907 | if (len <= 0) { | |
e54b3d7c | 908 | close_socket(&sockets[i]); |
3c0ef626 | 909 | break; |
910 | } | |
911 | buffer_consume(&sockets[i].output, len); | |
912 | } | |
913 | if (FD_ISSET(sockets[i].fd, readset)) { | |
914 | do { | |
915 | len = read(sockets[i].fd, buf, sizeof(buf)); | |
916 | if (len == -1 && (errno == EAGAIN || | |
917 | errno == EINTR)) | |
918 | continue; | |
919 | break; | |
920 | } while (1); | |
921 | if (len <= 0) { | |
e54b3d7c | 922 | close_socket(&sockets[i]); |
3c0ef626 | 923 | break; |
924 | } | |
925 | buffer_append(&sockets[i].input, buf, len); | |
926 | process_message(&sockets[i]); | |
927 | } | |
928 | break; | |
929 | default: | |
930 | fatal("Unknown type %d", sockets[i].type); | |
931 | } | |
932 | } | |
933 | ||
934 | static void | |
e9a17296 | 935 | cleanup_socket(void *p) |
3c0ef626 | 936 | { |
937 | if (socket_name[0]) | |
938 | unlink(socket_name); | |
939 | if (socket_dir[0]) | |
940 | rmdir(socket_dir); | |
941 | } | |
942 | ||
943 | static void | |
944 | cleanup_exit(int i) | |
945 | { | |
e9a17296 | 946 | cleanup_socket(NULL); |
3c0ef626 | 947 | exit(i); |
948 | } | |
949 | ||
950 | static void | |
951 | cleanup_handler(int sig) | |
952 | { | |
e9a17296 | 953 | cleanup_socket(NULL); |
3c0ef626 | 954 | _exit(2); |
955 | } | |
956 | ||
957 | static void | |
958 | check_parent_exists(int sig) | |
959 | { | |
960 | int save_errno = errno; | |
961 | ||
962 | if (parent_pid != -1 && kill(parent_pid, 0) < 0) { | |
963 | /* printf("Parent has died - Authentication agent exiting.\n"); */ | |
964 | cleanup_handler(sig); /* safe */ | |
965 | } | |
966 | signal(SIGALRM, check_parent_exists); | |
967 | alarm(10); | |
968 | errno = save_errno; | |
969 | } | |
970 | ||
971 | static void | |
972 | usage(void) | |
973 | { | |
974 | fprintf(stderr, "Usage: %s [options] [command [args ...]]\n", | |
975 | __progname); | |
976 | fprintf(stderr, "Options:\n"); | |
977 | fprintf(stderr, " -c Generate C-shell commands on stdout.\n"); | |
978 | fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n"); | |
979 | fprintf(stderr, " -k Kill the current agent.\n"); | |
980 | fprintf(stderr, " -d Debug mode.\n"); | |
ff2d7a98 | 981 | fprintf(stderr, " -a socket Bind agent socket to given name.\n"); |
1c14df9e | 982 | fprintf(stderr, " -t life Default identity lifetime (seconds).\n"); |
3c0ef626 | 983 | exit(1); |
984 | } | |
985 | ||
986 | int | |
987 | main(int ac, char **av) | |
988 | { | |
1c14df9e | 989 | int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0; |
990 | int sock, fd, ch, nalloc; | |
ff2d7a98 | 991 | char *shell, *format, *pidstr, *agentsocket = NULL; |
992 | fd_set *readsetp = NULL, *writesetp = NULL; | |
3c0ef626 | 993 | struct sockaddr_un sunaddr; |
994 | #ifdef HAVE_SETRLIMIT | |
995 | struct rlimit rlim; | |
996 | #endif | |
997 | #ifdef HAVE_CYGWIN | |
998 | int prev_mask; | |
999 | #endif | |
3c0ef626 | 1000 | extern int optind; |
ff2d7a98 | 1001 | extern char *optarg; |
1002 | pid_t pid; | |
1003 | char pidstrbuf[1 + 3 * sizeof pid]; | |
3c0ef626 | 1004 | |
e54b3d7c | 1005 | /* drop */ |
1006 | setegid(getgid()); | |
1007 | setgid(getgid()); | |
1008 | ||
3c0ef626 | 1009 | SSLeay_add_all_algorithms(); |
1010 | ||
1011 | __progname = get_progname(av[0]); | |
1265699a | 1012 | init_pathnames(); |
3c0ef626 | 1013 | init_rng(); |
1014 | seed_rng(); | |
1015 | ||
1c14df9e | 1016 | while ((ch = getopt(ac, av, "cdksa:t:")) != -1) { |
3c0ef626 | 1017 | switch (ch) { |
1018 | case 'c': | |
1019 | if (s_flag) | |
1020 | usage(); | |
1021 | c_flag++; | |
1022 | break; | |
1023 | case 'k': | |
1024 | k_flag++; | |
1025 | break; | |
1026 | case 's': | |
1027 | if (c_flag) | |
1028 | usage(); | |
1029 | s_flag++; | |
1030 | break; | |
1031 | case 'd': | |
1032 | if (d_flag) | |
1033 | usage(); | |
1034 | d_flag++; | |
1035 | break; | |
ff2d7a98 | 1036 | case 'a': |
1037 | agentsocket = optarg; | |
1038 | break; | |
1c14df9e | 1039 | case 't': |
1040 | if ((lifetime = convtime(optarg)) == -1) { | |
1041 | fprintf(stderr, "Invalid lifetime\n"); | |
1042 | usage(); | |
1043 | } | |
1044 | break; | |
3c0ef626 | 1045 | default: |
1046 | usage(); | |
1047 | } | |
1048 | } | |
1049 | ac -= optind; | |
1050 | av += optind; | |
1051 | ||
1052 | if (ac > 0 && (c_flag || k_flag || s_flag || d_flag)) | |
1053 | usage(); | |
1054 | ||
2980ea68 | 1055 | if (ac == 0 && !c_flag && !s_flag) { |
3c0ef626 | 1056 | shell = getenv("SHELL"); |
1057 | if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0) | |
1058 | c_flag = 1; | |
1059 | } | |
1060 | if (k_flag) { | |
1061 | pidstr = getenv(SSH_AGENTPID_ENV_NAME); | |
1062 | if (pidstr == NULL) { | |
1063 | fprintf(stderr, "%s not set, cannot kill agent\n", | |
1064 | SSH_AGENTPID_ENV_NAME); | |
1065 | exit(1); | |
1066 | } | |
1067 | pid = atoi(pidstr); | |
1068 | if (pid < 1) { | |
1069 | fprintf(stderr, "%s=\"%s\", which is not a good PID\n", | |
1070 | SSH_AGENTPID_ENV_NAME, pidstr); | |
1071 | exit(1); | |
1072 | } | |
1073 | if (kill(pid, SIGTERM) == -1) { | |
1074 | perror("kill"); | |
1075 | exit(1); | |
1076 | } | |
1077 | format = c_flag ? "unsetenv %s;\n" : "unset %s;\n"; | |
1078 | printf(format, SSH_AUTHSOCKET_ENV_NAME); | |
1079 | printf(format, SSH_AGENTPID_ENV_NAME); | |
ff2d7a98 | 1080 | printf("echo Agent pid %ld killed;\n", (long)pid); |
3c0ef626 | 1081 | exit(0); |
1082 | } | |
1083 | parent_pid = getpid(); | |
1084 | ||
ff2d7a98 | 1085 | if (agentsocket == NULL) { |
1086 | /* Create private directory for agent socket */ | |
1087 | strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir); | |
1088 | if (mkdtemp(socket_dir) == NULL) { | |
1089 | perror("mkdtemp: private socket dir"); | |
1090 | exit(1); | |
1091 | } | |
1092 | snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir, | |
1093 | (long)parent_pid); | |
1094 | } else { | |
1095 | /* Try to use specified agent socket */ | |
1096 | socket_dir[0] = '\0'; | |
1097 | strlcpy(socket_name, agentsocket, sizeof socket_name); | |
3c0ef626 | 1098 | } |
3c0ef626 | 1099 | |
1100 | /* | |
1101 | * Create socket early so it will exist before command gets run from | |
1102 | * the parent. | |
1103 | */ | |
1104 | sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
1105 | if (sock < 0) { | |
1106 | perror("socket"); | |
1107 | cleanup_exit(1); | |
1108 | } | |
1109 | memset(&sunaddr, 0, sizeof(sunaddr)); | |
1110 | sunaddr.sun_family = AF_UNIX; | |
1111 | strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path)); | |
1112 | #ifdef HAVE_CYGWIN | |
1113 | prev_mask = umask(0177); | |
1114 | #endif | |
1115 | if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) { | |
1116 | perror("bind"); | |
1117 | #ifdef HAVE_CYGWIN | |
1118 | umask(prev_mask); | |
1119 | #endif | |
1120 | cleanup_exit(1); | |
1121 | } | |
1122 | #ifdef HAVE_CYGWIN | |
1123 | umask(prev_mask); | |
1124 | #endif | |
e54b3d7c | 1125 | if (listen(sock, 128) < 0) { |
3c0ef626 | 1126 | perror("listen"); |
1127 | cleanup_exit(1); | |
1128 | } | |
1129 | ||
1130 | /* | |
1131 | * Fork, and have the parent execute the command, if any, or present | |
1132 | * the socket data. The child continues as the authentication agent. | |
1133 | */ | |
1134 | if (d_flag) { | |
1135 | log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1); | |
1136 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
1137 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
1138 | SSH_AUTHSOCKET_ENV_NAME); | |
ff2d7a98 | 1139 | printf("echo Agent pid %ld;\n", (long)parent_pid); |
3c0ef626 | 1140 | goto skip; |
1141 | } | |
1142 | pid = fork(); | |
1143 | if (pid == -1) { | |
1144 | perror("fork"); | |
e9a17296 | 1145 | cleanup_exit(1); |
3c0ef626 | 1146 | } |
1147 | if (pid != 0) { /* Parent - execute the given command. */ | |
1148 | close(sock); | |
ff2d7a98 | 1149 | snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid); |
3c0ef626 | 1150 | if (ac == 0) { |
1151 | format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n"; | |
1152 | printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name, | |
1153 | SSH_AUTHSOCKET_ENV_NAME); | |
1154 | printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf, | |
1155 | SSH_AGENTPID_ENV_NAME); | |
ff2d7a98 | 1156 | printf("echo Agent pid %ld;\n", (long)pid); |
3c0ef626 | 1157 | exit(0); |
1158 | } | |
1159 | if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 || | |
1160 | setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) { | |
1161 | perror("setenv"); | |
1162 | exit(1); | |
1163 | } | |
1164 | execvp(av[0], av); | |
1165 | perror(av[0]); | |
1166 | exit(1); | |
1167 | } | |
e9a17296 | 1168 | /* child */ |
1169 | log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0); | |
3c0ef626 | 1170 | |
1171 | if (setsid() == -1) { | |
e9a17296 | 1172 | error("setsid: %s", strerror(errno)); |
3c0ef626 | 1173 | cleanup_exit(1); |
1174 | } | |
1175 | ||
1176 | (void)chdir("/"); | |
1c14df9e | 1177 | if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) { |
1178 | /* XXX might close listen socket */ | |
1179 | (void)dup2(fd, STDIN_FILENO); | |
1180 | (void)dup2(fd, STDOUT_FILENO); | |
1181 | (void)dup2(fd, STDERR_FILENO); | |
1182 | if (fd > 2) | |
1183 | close(fd); | |
1184 | } | |
3c0ef626 | 1185 | |
1186 | #ifdef HAVE_SETRLIMIT | |
1187 | /* deny core dumps, since memory contains unencrypted private keys */ | |
1188 | rlim.rlim_cur = rlim.rlim_max = 0; | |
1189 | if (setrlimit(RLIMIT_CORE, &rlim) < 0) { | |
e9a17296 | 1190 | error("setrlimit RLIMIT_CORE: %s", strerror(errno)); |
3c0ef626 | 1191 | cleanup_exit(1); |
1192 | } | |
1193 | #endif | |
1194 | ||
1195 | skip: | |
e9a17296 | 1196 | fatal_add_cleanup(cleanup_socket, NULL); |
3c0ef626 | 1197 | new_socket(AUTH_SOCKET, sock); |
1198 | if (ac > 0) { | |
1199 | signal(SIGALRM, check_parent_exists); | |
1200 | alarm(10); | |
1201 | } | |
1202 | idtab_init(); | |
1203 | if (!d_flag) | |
1204 | signal(SIGINT, SIG_IGN); | |
1205 | signal(SIGPIPE, SIG_IGN); | |
1206 | signal(SIGHUP, cleanup_handler); | |
1207 | signal(SIGTERM, cleanup_handler); | |
1208 | nalloc = 0; | |
1209 | ||
1210 | while (1) { | |
1211 | prepare_select(&readsetp, &writesetp, &max_fd, &nalloc); | |
1212 | if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) { | |
1213 | if (errno == EINTR) | |
1214 | continue; | |
e9a17296 | 1215 | fatal("select: %s", strerror(errno)); |
3c0ef626 | 1216 | } |
1217 | after_select(readsetp, writesetp); | |
1218 | } | |
1219 | /* NOTREACHED */ | |
1220 | } |