Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.162
1.162 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.161 2009/03/23 19:38:04 tobias Exp $ */
1.1 deraadt 2: /*
1.22 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * The authentication agent program.
1.33 markus 7: *
1.35 deraadt 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: *
1.56 markus 14: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.35 deraadt 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.
1.22 deraadt 35: */
1.1 deraadt 36:
1.151 deraadt 37: #include <sys/types.h>
1.153 djm 38: #include <sys/time.h>
1.78 provos 39: #include <sys/queue.h>
1.127 stevesk 40: #include <sys/resource.h>
1.128 stevesk 41: #include <sys/types.h>
1.141 stevesk 42: #include <sys/socket.h>
1.128 stevesk 43: #include <sys/un.h>
1.148 stevesk 44: #include <sys/param.h>
1.126 stevesk 45:
1.146 stevesk 46: #include <openssl/evp.h>
47: #include <openssl/md5.h>
48:
1.143 stevesk 49: #include <errno.h>
1.142 stevesk 50: #include <fcntl.h>
1.126 stevesk 51: #include <paths.h>
1.129 stevesk 52: #include <signal.h>
1.149 stevesk 53: #include <stdlib.h>
1.150 stevesk 54: #include <stdio.h>
1.146 stevesk 55: #include <string.h>
1.145 stevesk 56: #include <time.h>
1.144 stevesk 57: #include <unistd.h>
1.1 deraadt 58:
1.151 deraadt 59: #include "xmalloc.h"
1.1 deraadt 60: #include "ssh.h"
61: #include "rsa.h"
62: #include "buffer.h"
1.32 markus 63: #include "key.h"
64: #include "authfd.h"
1.37 markus 65: #include "compat.h"
1.47 markus 66: #include "log.h"
1.107 markus 67: #include "misc.h"
1.7 deraadt 68:
1.59 markus 69: #ifdef SMARTCARD
70: #include "scard.h"
1.71 jakob 71: #endif
1.59 markus 72:
1.73 stevesk 73: typedef enum {
74: AUTH_UNUSED,
75: AUTH_SOCKET,
76: AUTH_CONNECTION
77: } sock_type;
78:
1.21 markus 79: typedef struct {
80: int fd;
1.73 stevesk 81: sock_type type;
1.21 markus 82: Buffer input;
83: Buffer output;
1.87 markus 84: Buffer request;
1.1 deraadt 85: } SocketEntry;
86:
1.45 markus 87: u_int sockets_alloc = 0;
1.1 deraadt 88: SocketEntry *sockets = NULL;
89:
1.78 provos 90: typedef struct identity {
91: TAILQ_ENTRY(identity) next;
1.33 markus 92: Key *key;
1.21 markus 93: char *comment;
1.89 markus 94: u_int death;
1.107 markus 95: u_int confirm;
1.1 deraadt 96: } Identity;
97:
1.33 markus 98: typedef struct {
99: int nentries;
1.78 provos 100: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 101: } Idtab;
102:
103: /* private key table, one per protocol version */
104: Idtab idtable[3];
1.1 deraadt 105:
106: int max_fd = 0;
107:
1.11 markus 108: /* pid of shell == parent of agent */
1.29 deraadt 109: pid_t parent_pid = -1;
1.155 dtucker 110: u_int parent_alive_interval = 0;
1.10 markus 111:
112: /* pathname and directory for AUTH_SOCKET */
1.132 djm 113: char socket_name[MAXPATHLEN];
114: char socket_dir[MAXPATHLEN];
1.10 markus 115:
1.88 markus 116: /* locking */
117: int locked = 0;
118: char *lock_passwd = NULL;
119:
1.20 markus 120: extern char *__progname;
121:
1.106 marc 122: /* Default lifetime (0 == forever) */
123: static int lifetime = 0;
124:
1.55 itojun 125: static void
1.101 stevesk 126: close_socket(SocketEntry *e)
127: {
128: close(e->fd);
129: e->fd = -1;
130: e->type = AUTH_UNUSED;
131: buffer_free(&e->input);
132: buffer_free(&e->output);
133: buffer_free(&e->request);
134: }
135:
136: static void
1.33 markus 137: idtab_init(void)
1.1 deraadt 138: {
1.33 markus 139: int i;
1.96 deraadt 140:
1.74 deraadt 141: for (i = 0; i <=2; i++) {
1.78 provos 142: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 143: idtable[i].nentries = 0;
144: }
145: }
146:
147: /* return private key table for requested protocol version */
1.55 itojun 148: static Idtab *
1.33 markus 149: idtab_lookup(int version)
150: {
151: if (version < 1 || version > 2)
152: fatal("internal error, bad protocol version %d", version);
153: return &idtable[version];
154: }
155:
1.89 markus 156: static void
157: free_identity(Identity *id)
158: {
159: key_free(id->key);
160: xfree(id->comment);
161: xfree(id);
162: }
163:
1.33 markus 164: /* return matching private key for given public key */
1.78 provos 165: static Identity *
166: lookup_identity(Key *key, int version)
1.33 markus 167: {
1.78 provos 168: Identity *id;
169:
1.33 markus 170: Idtab *tab = idtab_lookup(version);
1.78 provos 171: TAILQ_FOREACH(id, &tab->idlist, next) {
172: if (key_equal(key, id->key))
173: return (id);
1.33 markus 174: }
1.78 provos 175: return (NULL);
176: }
177:
1.107 markus 178: /* Check confirmation of keysign request */
179: static int
180: confirm_key(Identity *id)
181: {
1.122 djm 182: char *p;
1.107 markus 183: int ret = -1;
184:
185: p = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
1.122 djm 186: if (ask_permission("Allow use of key %s?\nKey fingerprint %s.",
187: id->comment, p))
188: ret = 0;
1.107 markus 189: xfree(p);
1.122 djm 190:
1.107 markus 191: return (ret);
192: }
193:
1.33 markus 194: /* send list of supported public keys to 'client' */
1.55 itojun 195: static void
1.33 markus 196: process_request_identities(SocketEntry *e, int version)
197: {
198: Idtab *tab = idtab_lookup(version);
1.96 deraadt 199: Identity *id;
1.21 markus 200: Buffer msg;
1.1 deraadt 201:
1.21 markus 202: buffer_init(&msg);
1.33 markus 203: buffer_put_char(&msg, (version == 1) ?
204: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
205: buffer_put_int(&msg, tab->nentries);
1.78 provos 206: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 207: if (id->key->type == KEY_RSA1) {
1.33 markus 208: buffer_put_int(&msg, BN_num_bits(id->key->rsa->n));
209: buffer_put_bignum(&msg, id->key->rsa->e);
210: buffer_put_bignum(&msg, id->key->rsa->n);
211: } else {
1.45 markus 212: u_char *blob;
213: u_int blen;
1.39 markus 214: key_to_blob(id->key, &blob, &blen);
1.33 markus 215: buffer_put_string(&msg, blob, blen);
216: xfree(blob);
217: }
218: buffer_put_cstring(&msg, id->comment);
1.21 markus 219: }
220: buffer_put_int(&e->output, buffer_len(&msg));
221: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
222: buffer_free(&msg);
1.1 deraadt 223: }
224:
1.33 markus 225: /* ssh1 only */
1.55 itojun 226: static void
1.33 markus 227: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 228: {
1.96 deraadt 229: u_char buf[32], mdbuf[16], session_id[16];
230: u_int response_type;
231: BIGNUM *challenge;
1.78 provos 232: Identity *id;
1.33 markus 233: int i, len;
1.21 markus 234: Buffer msg;
235: MD5_CTX md;
1.96 deraadt 236: Key *key;
1.21 markus 237:
238: buffer_init(&msg);
1.39 markus 239: key = key_new(KEY_RSA1);
1.76 markus 240: if ((challenge = BN_new()) == NULL)
241: fatal("process_authentication_challenge1: BN_new failed");
1.33 markus 242:
1.97 markus 243: (void) buffer_get_int(&e->request); /* ignored */
1.87 markus 244: buffer_get_bignum(&e->request, key->rsa->e);
245: buffer_get_bignum(&e->request, key->rsa->n);
246: buffer_get_bignum(&e->request, challenge);
1.21 markus 247:
1.33 markus 248: /* Only protocol 1.1 is supported */
1.87 markus 249: if (buffer_len(&e->request) == 0)
1.33 markus 250: goto failure;
1.87 markus 251: buffer_get(&e->request, session_id, 16);
252: response_type = buffer_get_int(&e->request);
1.33 markus 253: if (response_type != 1)
254: goto failure;
255:
1.78 provos 256: id = lookup_identity(key, 1);
1.107 markus 257: if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
1.78 provos 258: Key *private = id->key;
1.33 markus 259: /* Decrypt the challenge using the private key. */
1.49 markus 260: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
261: goto failure;
1.33 markus 262:
263: /* The response is MD5 of decrypted challenge plus session id. */
264: len = BN_num_bytes(challenge);
265: if (len <= 0 || len > 32) {
1.109 itojun 266: logit("process_authentication_challenge: bad challenge length %d", len);
1.33 markus 267: goto failure;
268: }
269: memset(buf, 0, 32);
270: BN_bn2bin(challenge, buf + 32 - len);
271: MD5_Init(&md);
272: MD5_Update(&md, buf, 32);
273: MD5_Update(&md, session_id, 16);
274: MD5_Final(mdbuf, &md);
275:
276: /* Send the response. */
277: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
278: for (i = 0; i < 16; i++)
279: buffer_put_char(&msg, mdbuf[i]);
280: goto send;
281: }
1.21 markus 282:
1.33 markus 283: failure:
284: /* Unknown identity or protocol error. Send failure. */
1.21 markus 285: buffer_put_char(&msg, SSH_AGENT_FAILURE);
286: send:
287: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 288: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
289: key_free(key);
290: BN_clear_free(challenge);
291: buffer_free(&msg);
292: }
293:
294: /* ssh2 only */
1.55 itojun 295: static void
1.33 markus 296: process_sign_request2(SocketEntry *e)
297: {
1.45 markus 298: u_char *blob, *data, *signature = NULL;
299: u_int blen, dlen, slen = 0;
1.96 deraadt 300: extern int datafellows;
1.159 djm 301: int odatafellows;
1.96 deraadt 302: int ok = -1, flags;
1.33 markus 303: Buffer msg;
1.96 deraadt 304: Key *key;
1.33 markus 305:
306: datafellows = 0;
1.43 markus 307:
1.87 markus 308: blob = buffer_get_string(&e->request, &blen);
309: data = buffer_get_string(&e->request, &dlen);
1.37 markus 310:
1.87 markus 311: flags = buffer_get_int(&e->request);
1.159 djm 312: odatafellows = datafellows;
1.37 markus 313: if (flags & SSH_AGENT_OLD_SIGNATURE)
314: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 315:
1.39 markus 316: key = key_from_blob(blob, blen);
1.33 markus 317: if (key != NULL) {
1.78 provos 318: Identity *id = lookup_identity(key, 2);
1.107 markus 319: if (id != NULL && (!id->confirm || confirm_key(id) == 0))
1.78 provos 320: ok = key_sign(id->key, &signature, &slen, data, dlen);
1.138 markus 321: key_free(key);
1.33 markus 322: }
323: buffer_init(&msg);
324: if (ok == 0) {
325: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
326: buffer_put_string(&msg, signature, slen);
327: } else {
328: buffer_put_char(&msg, SSH_AGENT_FAILURE);
329: }
330: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 331: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 332: buffer_len(&msg));
1.21 markus 333: buffer_free(&msg);
1.33 markus 334: xfree(data);
335: xfree(blob);
336: if (signature != NULL)
337: xfree(signature);
1.159 djm 338: datafellows = odatafellows;
1.1 deraadt 339: }
340:
1.33 markus 341: /* shared */
1.55 itojun 342: static void
1.33 markus 343: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 344: {
1.96 deraadt 345: u_int blen, bits;
346: int success = 0;
1.78 provos 347: Key *key = NULL;
1.45 markus 348: u_char *blob;
1.21 markus 349:
1.74 deraadt 350: switch (version) {
1.33 markus 351: case 1:
1.39 markus 352: key = key_new(KEY_RSA1);
1.87 markus 353: bits = buffer_get_int(&e->request);
354: buffer_get_bignum(&e->request, key->rsa->e);
355: buffer_get_bignum(&e->request, key->rsa->n);
1.33 markus 356:
357: if (bits != key_size(key))
1.109 itojun 358: logit("Warning: identity keysize mismatch: actual %u, announced %u",
1.46 markus 359: key_size(key), bits);
1.33 markus 360: break;
361: case 2:
1.87 markus 362: blob = buffer_get_string(&e->request, &blen);
1.39 markus 363: key = key_from_blob(blob, blen);
1.33 markus 364: xfree(blob);
365: break;
366: }
367: if (key != NULL) {
1.78 provos 368: Identity *id = lookup_identity(key, version);
369: if (id != NULL) {
1.23 markus 370: /*
371: * We have this key. Free the old key. Since we
1.124 djm 372: * don't want to leave empty slots in the middle of
1.40 markus 373: * the array, we actually free the key there and move
374: * all the entries between the empty slot and the end
375: * of the array.
1.23 markus 376: */
1.33 markus 377: Idtab *tab = idtab_lookup(version);
1.38 markus 378: if (tab->nentries < 1)
379: fatal("process_remove_identity: "
380: "internal error: tab->nentries %d",
381: tab->nentries);
1.78 provos 382: TAILQ_REMOVE(&tab->idlist, id, next);
383: free_identity(id);
1.33 markus 384: tab->nentries--;
385: success = 1;
1.21 markus 386: }
1.33 markus 387: key_free(key);
388: }
1.1 deraadt 389: buffer_put_int(&e->output, 1);
1.33 markus 390: buffer_put_char(&e->output,
391: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 392: }
393:
1.55 itojun 394: static void
1.33 markus 395: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 396: {
1.33 markus 397: Idtab *tab = idtab_lookup(version);
1.78 provos 398: Identity *id;
1.21 markus 399:
400: /* Loop over all identities and clear the keys. */
1.78 provos 401: for (id = TAILQ_FIRST(&tab->idlist); id;
402: id = TAILQ_FIRST(&tab->idlist)) {
403: TAILQ_REMOVE(&tab->idlist, id, next);
404: free_identity(id);
1.21 markus 405: }
406:
407: /* Mark that there are no identities. */
1.33 markus 408: tab->nentries = 0;
1.21 markus 409:
410: /* Send success. */
411: buffer_put_int(&e->output, 1);
412: buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
1.1 deraadt 413: }
414:
1.155 dtucker 415: /* removes expired keys and returns number of seconds until the next expiry */
416: static u_int
1.89 markus 417: reaper(void)
418: {
1.155 dtucker 419: u_int deadline = 0, now = time(NULL);
1.89 markus 420: Identity *id, *nxt;
421: int version;
1.96 deraadt 422: Idtab *tab;
1.89 markus 423:
424: for (version = 1; version < 3; version++) {
425: tab = idtab_lookup(version);
426: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
427: nxt = TAILQ_NEXT(id, next);
1.155 dtucker 428: if (id->death == 0)
429: continue;
430: if (now >= id->death) {
1.154 dtucker 431: debug("expiring key '%s'", id->comment);
1.89 markus 432: TAILQ_REMOVE(&tab->idlist, id, next);
433: free_identity(id);
434: tab->nentries--;
1.155 dtucker 435: } else
436: deadline = (deadline == 0) ? id->death :
437: MIN(deadline, id->death);
1.89 markus 438: }
439: }
1.155 dtucker 440: if (deadline == 0 || deadline <= now)
441: return 0;
442: else
443: return (deadline - now);
1.89 markus 444: }
445:
446: static void
1.33 markus 447: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 448: {
1.96 deraadt 449: Idtab *tab = idtab_lookup(version);
1.157 canacar 450: Identity *id;
1.107 markus 451: int type, success = 0, death = 0, confirm = 0;
1.96 deraadt 452: char *type_name, *comment;
1.33 markus 453: Key *k = NULL;
454:
455: switch (version) {
456: case 1:
1.39 markus 457: k = key_new_private(KEY_RSA1);
1.97 markus 458: (void) buffer_get_int(&e->request); /* ignored */
1.87 markus 459: buffer_get_bignum(&e->request, k->rsa->n);
460: buffer_get_bignum(&e->request, k->rsa->e);
461: buffer_get_bignum(&e->request, k->rsa->d);
462: buffer_get_bignum(&e->request, k->rsa->iqmp);
1.33 markus 463:
464: /* SSH and SSL have p and q swapped */
1.87 markus 465: buffer_get_bignum(&e->request, k->rsa->q); /* p */
466: buffer_get_bignum(&e->request, k->rsa->p); /* q */
1.33 markus 467:
468: /* Generate additional parameters */
1.60 markus 469: rsa_generate_additional_parameters(k->rsa);
1.33 markus 470: break;
471: case 2:
1.87 markus 472: type_name = buffer_get_string(&e->request, NULL);
1.46 markus 473: type = key_type_from_name(type_name);
1.39 markus 474: xfree(type_name);
1.74 deraadt 475: switch (type) {
1.39 markus 476: case KEY_DSA:
477: k = key_new_private(type);
1.87 markus 478: buffer_get_bignum2(&e->request, k->dsa->p);
479: buffer_get_bignum2(&e->request, k->dsa->q);
480: buffer_get_bignum2(&e->request, k->dsa->g);
481: buffer_get_bignum2(&e->request, k->dsa->pub_key);
482: buffer_get_bignum2(&e->request, k->dsa->priv_key);
1.39 markus 483: break;
484: case KEY_RSA:
485: k = key_new_private(type);
1.87 markus 486: buffer_get_bignum2(&e->request, k->rsa->n);
487: buffer_get_bignum2(&e->request, k->rsa->e);
488: buffer_get_bignum2(&e->request, k->rsa->d);
489: buffer_get_bignum2(&e->request, k->rsa->iqmp);
490: buffer_get_bignum2(&e->request, k->rsa->p);
491: buffer_get_bignum2(&e->request, k->rsa->q);
1.39 markus 492:
493: /* Generate additional parameters */
1.60 markus 494: rsa_generate_additional_parameters(k->rsa);
1.39 markus 495: break;
496: default:
1.87 markus 497: buffer_clear(&e->request);
1.108 markus 498: goto send;
499: }
500: break;
501: }
502: /* enable blinding */
503: switch (k->type) {
504: case KEY_RSA:
505: case KEY_RSA1:
506: if (RSA_blinding_on(k->rsa, NULL) != 1) {
507: error("process_add_identity: RSA_blinding_on failed");
508: key_free(k);
1.33 markus 509: goto send;
1.21 markus 510: }
1.33 markus 511: break;
512: }
1.87 markus 513: comment = buffer_get_string(&e->request, NULL);
1.33 markus 514: if (k == NULL) {
515: xfree(comment);
516: goto send;
517: }
1.94 markus 518: while (buffer_len(&e->request)) {
1.158 djm 519: switch ((type = buffer_get_char(&e->request))) {
1.94 markus 520: case SSH_AGENT_CONSTRAIN_LIFETIME:
521: death = time(NULL) + buffer_get_int(&e->request);
522: break;
1.107 markus 523: case SSH_AGENT_CONSTRAIN_CONFIRM:
524: confirm = 1;
525: break;
1.94 markus 526: default:
1.158 djm 527: error("process_add_identity: "
528: "Unknown constraint type %d", type);
529: xfree(comment);
530: key_free(k);
531: goto send;
1.94 markus 532: }
533: }
1.158 djm 534: success = 1;
1.106 marc 535: if (lifetime && !death)
536: death = time(NULL) + lifetime;
1.157 canacar 537: if ((id = lookup_identity(k, version)) == NULL) {
538: id = xmalloc(sizeof(Identity));
1.78 provos 539: id->key = k;
540: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 541: /* Increment the number of identities. */
542: tab->nentries++;
543: } else {
544: key_free(k);
1.157 canacar 545: xfree(id->comment);
1.33 markus 546: }
1.157 canacar 547: id->comment = comment;
548: id->death = death;
549: id->confirm = confirm;
1.33 markus 550: send:
1.1 deraadt 551: buffer_put_int(&e->output, 1);
1.33 markus 552: buffer_put_char(&e->output,
553: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 554: }
555:
1.88 markus 556: /* XXX todo: encrypt sensitive data with passphrase */
557: static void
558: process_lock_agent(SocketEntry *e, int lock)
559: {
1.96 deraadt 560: int success = 0;
1.88 markus 561: char *passwd;
562:
563: passwd = buffer_get_string(&e->request, NULL);
564: if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
565: locked = 0;
566: memset(lock_passwd, 0, strlen(lock_passwd));
567: xfree(lock_passwd);
568: lock_passwd = NULL;
569: success = 1;
570: } else if (!locked && lock) {
571: locked = 1;
572: lock_passwd = xstrdup(passwd);
573: success = 1;
574: }
575: memset(passwd, 0, strlen(passwd));
576: xfree(passwd);
1.95 deraadt 577:
1.88 markus 578: buffer_put_int(&e->output, 1);
579: buffer_put_char(&e->output,
580: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
581: }
582:
583: static void
584: no_identities(SocketEntry *e, u_int type)
585: {
586: Buffer msg;
587:
588: buffer_init(&msg);
589: buffer_put_char(&msg,
590: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
591: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
592: buffer_put_int(&msg, 0);
593: buffer_put_int(&e->output, buffer_len(&msg));
594: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
595: buffer_free(&msg);
596: }
1.59 markus 597:
598: #ifdef SMARTCARD
599: static void
1.158 djm 600: process_add_smartcard_key(SocketEntry *e)
1.59 markus 601: {
1.96 deraadt 602: char *sc_reader_id = NULL, *pin;
1.158 djm 603: int i, type, version, success = 0, death = 0, confirm = 0;
1.96 deraadt 604: Key **keys, *k;
1.84 markus 605: Identity *id;
1.59 markus 606: Idtab *tab;
1.75 deraadt 607:
1.87 markus 608: sc_reader_id = buffer_get_string(&e->request, NULL);
609: pin = buffer_get_string(&e->request, NULL);
1.110 djm 610:
611: while (buffer_len(&e->request)) {
1.158 djm 612: switch ((type = buffer_get_char(&e->request))) {
1.110 djm 613: case SSH_AGENT_CONSTRAIN_LIFETIME:
614: death = time(NULL) + buffer_get_int(&e->request);
615: break;
616: case SSH_AGENT_CONSTRAIN_CONFIRM:
617: confirm = 1;
618: break;
619: default:
1.158 djm 620: error("process_add_smartcard_key: "
621: "Unknown constraint type %d", type);
622: xfree(sc_reader_id);
623: xfree(pin);
624: goto send;
1.110 djm 625: }
626: }
627: if (lifetime && !death)
628: death = time(NULL) + lifetime;
629:
1.84 markus 630: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 631: xfree(sc_reader_id);
1.83 rees 632: xfree(pin);
1.59 markus 633:
1.84 markus 634: if (keys == NULL || keys[0] == NULL) {
635: error("sc_get_keys failed");
1.59 markus 636: goto send;
637: }
1.84 markus 638: for (i = 0; keys[i] != NULL; i++) {
639: k = keys[i];
640: version = k->type == KEY_RSA1 ? 1 : 2;
641: tab = idtab_lookup(version);
642: if (lookup_identity(k, version) == NULL) {
643: id = xmalloc(sizeof(Identity));
644: id->key = k;
1.111 markus 645: id->comment = sc_get_key_label(k);
1.110 djm 646: id->death = death;
647: id->confirm = confirm;
1.84 markus 648: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
649: tab->nentries++;
650: success = 1;
651: } else {
652: key_free(k);
653: }
654: keys[i] = NULL;
1.59 markus 655: }
1.84 markus 656: xfree(keys);
1.59 markus 657: send:
658: buffer_put_int(&e->output, 1);
659: buffer_put_char(&e->output,
660: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
661: }
662:
663: static void
664: process_remove_smartcard_key(SocketEntry *e)
665: {
1.96 deraadt 666: char *sc_reader_id = NULL, *pin;
667: int i, version, success = 0;
668: Key **keys, *k = NULL;
1.84 markus 669: Identity *id;
670: Idtab *tab;
1.59 markus 671:
1.87 markus 672: sc_reader_id = buffer_get_string(&e->request, NULL);
673: pin = buffer_get_string(&e->request, NULL);
1.84 markus 674: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 675: xfree(sc_reader_id);
1.83 rees 676: xfree(pin);
1.59 markus 677:
1.84 markus 678: if (keys == NULL || keys[0] == NULL) {
679: error("sc_get_keys failed");
680: goto send;
681: }
682: for (i = 0; keys[i] != NULL; i++) {
683: k = keys[i];
684: version = k->type == KEY_RSA1 ? 1 : 2;
685: if ((id = lookup_identity(k, version)) != NULL) {
686: tab = idtab_lookup(version);
1.90 markus 687: TAILQ_REMOVE(&tab->idlist, id, next);
1.59 markus 688: tab->nentries--;
1.78 provos 689: free_identity(id);
1.59 markus 690: success = 1;
691: }
692: key_free(k);
1.84 markus 693: keys[i] = NULL;
1.59 markus 694: }
1.84 markus 695: xfree(keys);
696: send:
1.59 markus 697: buffer_put_int(&e->output, 1);
698: buffer_put_char(&e->output,
699: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
700: }
1.70 jakob 701: #endif /* SMARTCARD */
1.59 markus 702:
1.33 markus 703: /* dispatch incoming messages */
704:
1.55 itojun 705: static void
1.2 provos 706: process_message(SocketEntry *e)
1.1 deraadt 707: {
1.96 deraadt 708: u_int msg_len, type;
1.45 markus 709: u_char *cp;
1.89 markus 710:
1.21 markus 711: if (buffer_len(&e->input) < 5)
712: return; /* Incomplete message. */
1.77 stevesk 713: cp = buffer_ptr(&e->input);
1.137 djm 714: msg_len = get_u32(cp);
1.21 markus 715: if (msg_len > 256 * 1024) {
1.101 stevesk 716: close_socket(e);
1.21 markus 717: return;
718: }
719: if (buffer_len(&e->input) < msg_len + 4)
720: return;
1.87 markus 721:
722: /* move the current input to e->request */
1.21 markus 723: buffer_consume(&e->input, 4);
1.87 markus 724: buffer_clear(&e->request);
725: buffer_append(&e->request, buffer_ptr(&e->input), msg_len);
726: buffer_consume(&e->input, msg_len);
727: type = buffer_get_char(&e->request);
1.21 markus 728:
1.88 markus 729: /* check wheter agent is locked */
730: if (locked && type != SSH_AGENTC_UNLOCK) {
731: buffer_clear(&e->request);
732: switch (type) {
733: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
734: case SSH2_AGENTC_REQUEST_IDENTITIES:
735: /* send empty lists */
736: no_identities(e, type);
737: break;
738: default:
739: /* send a fail message for all other request types */
740: buffer_put_int(&e->output, 1);
741: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
742: }
743: return;
744: }
745:
1.59 markus 746: debug("type %d", type);
1.21 markus 747: switch (type) {
1.88 markus 748: case SSH_AGENTC_LOCK:
749: case SSH_AGENTC_UNLOCK:
750: process_lock_agent(e, type == SSH_AGENTC_LOCK);
751: break;
1.33 markus 752: /* ssh1 */
753: case SSH_AGENTC_RSA_CHALLENGE:
754: process_authentication_challenge1(e);
755: break;
1.21 markus 756: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 757: process_request_identities(e, 1);
1.21 markus 758: break;
759: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.94 markus 760: case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
1.33 markus 761: process_add_identity(e, 1);
1.21 markus 762: break;
763: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 764: process_remove_identity(e, 1);
1.21 markus 765: break;
766: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 767: process_remove_all_identities(e, 1);
768: break;
769: /* ssh2 */
770: case SSH2_AGENTC_SIGN_REQUEST:
771: process_sign_request2(e);
772: break;
773: case SSH2_AGENTC_REQUEST_IDENTITIES:
774: process_request_identities(e, 2);
775: break;
776: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 777: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.33 markus 778: process_add_identity(e, 2);
779: break;
780: case SSH2_AGENTC_REMOVE_IDENTITY:
781: process_remove_identity(e, 2);
782: break;
783: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
784: process_remove_all_identities(e, 2);
1.21 markus 785: break;
1.59 markus 786: #ifdef SMARTCARD
787: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 788: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 789: process_add_smartcard_key(e);
1.75 deraadt 790: break;
1.59 markus 791: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
792: process_remove_smartcard_key(e);
1.75 deraadt 793: break;
1.70 jakob 794: #endif /* SMARTCARD */
1.21 markus 795: default:
796: /* Unknown message. Respond with failure. */
797: error("Unknown message %d", type);
1.87 markus 798: buffer_clear(&e->request);
1.21 markus 799: buffer_put_int(&e->output, 1);
800: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
801: break;
802: }
1.1 deraadt 803: }
804:
1.55 itojun 805: static void
1.73 stevesk 806: new_socket(sock_type type, int fd)
1.1 deraadt 807: {
1.112 markus 808: u_int i, old_alloc, new_alloc;
1.96 deraadt 809:
1.119 djm 810: set_nonblock(fd);
1.21 markus 811:
812: if (fd > max_fd)
813: max_fd = fd;
814:
815: for (i = 0; i < sockets_alloc; i++)
816: if (sockets[i].type == AUTH_UNUSED) {
817: sockets[i].fd = fd;
818: buffer_init(&sockets[i].input);
819: buffer_init(&sockets[i].output);
1.87 markus 820: buffer_init(&sockets[i].request);
1.112 markus 821: sockets[i].type = type;
1.21 markus 822: return;
823: }
824: old_alloc = sockets_alloc;
1.112 markus 825: new_alloc = sockets_alloc + 10;
1.133 djm 826: sockets = xrealloc(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 827: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 828: sockets[i].type = AUTH_UNUSED;
1.112 markus 829: sockets_alloc = new_alloc;
1.21 markus 830: sockets[old_alloc].fd = fd;
831: buffer_init(&sockets[old_alloc].input);
832: buffer_init(&sockets[old_alloc].output);
1.87 markus 833: buffer_init(&sockets[old_alloc].request);
1.112 markus 834: sockets[old_alloc].type = type;
1.1 deraadt 835: }
836:
1.55 itojun 837: static int
1.155 dtucker 838: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
839: struct timeval **tvpp)
1.1 deraadt 840: {
1.155 dtucker 841: u_int i, sz, deadline;
1.46 markus 842: int n = 0;
1.155 dtucker 843: static struct timeval tv;
1.46 markus 844:
845: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 846: switch (sockets[i].type) {
847: case AUTH_SOCKET:
848: case AUTH_CONNECTION:
1.46 markus 849: n = MAX(n, sockets[i].fd);
1.21 markus 850: break;
851: case AUTH_UNUSED:
852: break;
853: default:
854: fatal("Unknown socket type %d", sockets[i].type);
855: break;
856: }
1.46 markus 857: }
858:
859: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 860: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 861: if (*fdrp)
1.54 stevesk 862: xfree(*fdrp);
1.46 markus 863: if (*fdwp)
1.54 stevesk 864: xfree(*fdwp);
1.46 markus 865: *fdrp = xmalloc(sz);
866: *fdwp = xmalloc(sz);
1.66 markus 867: *nallocp = sz;
1.46 markus 868: }
1.66 markus 869: if (n < *fdl)
870: debug("XXX shrink: %d < %d", n, *fdl);
871: *fdl = n;
1.46 markus 872: memset(*fdrp, 0, sz);
873: memset(*fdwp, 0, sz);
874:
875: for (i = 0; i < sockets_alloc; i++) {
876: switch (sockets[i].type) {
877: case AUTH_SOCKET:
878: case AUTH_CONNECTION:
879: FD_SET(sockets[i].fd, *fdrp);
880: if (buffer_len(&sockets[i].output) > 0)
881: FD_SET(sockets[i].fd, *fdwp);
882: break;
883: default:
884: break;
885: }
886: }
1.155 dtucker 887: deadline = reaper();
888: if (parent_alive_interval != 0)
889: deadline = (deadline == 0) ? parent_alive_interval :
890: MIN(deadline, parent_alive_interval);
891: if (deadline == 0) {
892: *tvpp = NULL;
893: } else {
894: tv.tv_sec = deadline;
895: tv.tv_usec = 0;
896: *tvpp = &tv;
897: }
1.46 markus 898: return (1);
1.21 markus 899: }
900:
1.55 itojun 901: static void
1.21 markus 902: after_select(fd_set *readset, fd_set *writeset)
903: {
1.96 deraadt 904: struct sockaddr_un sunaddr;
1.26 markus 905: socklen_t slen;
1.21 markus 906: char buf[1024];
1.96 deraadt 907: int len, sock;
1.162 ! djm 908: u_int i, orig_alloc;
1.103 markus 909: uid_t euid;
910: gid_t egid;
1.21 markus 911:
1.162 ! djm 912: for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
1.21 markus 913: switch (sockets[i].type) {
914: case AUTH_UNUSED:
915: break;
916: case AUTH_SOCKET:
917: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 918: slen = sizeof(sunaddr);
1.46 markus 919: sock = accept(sockets[i].fd,
1.131 deraadt 920: (struct sockaddr *)&sunaddr, &slen);
1.21 markus 921: if (sock < 0) {
1.81 stevesk 922: error("accept from AUTH_SOCKET: %s",
923: strerror(errno));
1.103 markus 924: break;
925: }
926: if (getpeereid(sock, &euid, &egid) < 0) {
927: error("getpeereid %d failed: %s",
928: sock, strerror(errno));
929: close(sock);
930: break;
931: }
1.105 markus 932: if ((euid != 0) && (getuid() != euid)) {
1.103 markus 933: error("uid mismatch: "
1.104 stevesk 934: "peer euid %u != uid %u",
935: (u_int) euid, (u_int) getuid());
1.103 markus 936: close(sock);
1.21 markus 937: break;
938: }
939: new_socket(AUTH_CONNECTION, sock);
940: }
941: break;
942: case AUTH_CONNECTION:
943: if (buffer_len(&sockets[i].output) > 0 &&
944: FD_ISSET(sockets[i].fd, writeset)) {
1.162 ! djm 945: len = write(sockets[i].fd,
! 946: buffer_ptr(&sockets[i].output),
! 947: buffer_len(&sockets[i].output));
! 948: if (len == -1 && (errno == EAGAIN ||
! 949: errno == EINTR))
! 950: continue;
1.21 markus 951: if (len <= 0) {
1.101 stevesk 952: close_socket(&sockets[i]);
1.21 markus 953: break;
954: }
955: buffer_consume(&sockets[i].output, len);
956: }
957: if (FD_ISSET(sockets[i].fd, readset)) {
1.162 ! djm 958: len = read(sockets[i].fd, buf, sizeof(buf));
! 959: if (len == -1 && (errno == EAGAIN ||
! 960: errno == EINTR))
! 961: continue;
1.21 markus 962: if (len <= 0) {
1.101 stevesk 963: close_socket(&sockets[i]);
1.21 markus 964: break;
965: }
966: buffer_append(&sockets[i].input, buf, len);
967: process_message(&sockets[i]);
968: }
969: break;
970: default:
971: fatal("Unknown type %d", sockets[i].type);
972: }
1.1 deraadt 973: }
974:
1.55 itojun 975: static void
1.113 markus 976: cleanup_socket(void)
1.15 markus 977: {
1.48 deraadt 978: if (socket_name[0])
979: unlink(socket_name);
980: if (socket_dir[0])
981: rmdir(socket_dir);
1.10 markus 982: }
983:
1.114 markus 984: void
1.15 markus 985: cleanup_exit(int i)
986: {
1.113 markus 987: cleanup_socket();
988: _exit(i);
1.15 markus 989: }
990:
1.135 deraadt 991: /*ARGSUSED*/
1.55 itojun 992: static void
1.48 deraadt 993: cleanup_handler(int sig)
994: {
1.113 markus 995: cleanup_socket();
1.48 deraadt 996: _exit(2);
1.113 markus 997: }
998:
1.68 markus 999: static void
1.155 dtucker 1000: check_parent_exists(void)
1.68 markus 1001: {
1002: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
1003: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1004: cleanup_socket();
1005: _exit(2);
1.68 markus 1006: }
1.48 deraadt 1007: }
1008:
1.55 itojun 1009: static void
1.50 itojun 1010: usage(void)
1.15 markus 1011: {
1.156 sobrado 1012: fprintf(stderr, "usage: %s [options] [command [arg ...]]\n",
1.46 markus 1013: __progname);
1.72 jakob 1014: fprintf(stderr, "Options:\n");
1015: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
1016: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
1017: fprintf(stderr, " -k Kill the current agent.\n");
1018: fprintf(stderr, " -d Debug mode.\n");
1.86 markus 1019: fprintf(stderr, " -a socket Bind agent socket to given name.\n");
1.106 marc 1020: fprintf(stderr, " -t life Default identity lifetime (seconds).\n");
1.21 markus 1021: exit(1);
1.15 markus 1022: }
1023:
1.2 provos 1024: int
1025: main(int ac, char **av)
1.1 deraadt 1026: {
1.107 markus 1027: int c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1028: int sock, fd, ch, result, saved_errno;
1.120 avsm 1029: u_int nalloc;
1.96 deraadt 1030: char *shell, *format, *pidstr, *agentsocket = NULL;
1031: fd_set *readsetp = NULL, *writesetp = NULL;
1.21 markus 1032: struct sockaddr_un sunaddr;
1.41 markus 1033: struct rlimit rlim;
1.96 deraadt 1034: extern int optind;
1.98 stevesk 1035: extern char *optarg;
1.21 markus 1036: pid_t pid;
1.96 deraadt 1037: char pidstrbuf[1 + 3 * sizeof pid];
1.155 dtucker 1038: struct timeval *tvp = NULL;
1.161 tobias 1039: size_t len;
1.123 djm 1040:
1041: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1042: sanitise_stdfd();
1.99 markus 1043:
1044: /* drop */
1045: setegid(getgid());
1046: setgid(getgid());
1.53 markus 1047:
1048: SSLeay_add_all_algorithms();
1.21 markus 1049:
1.106 marc 1050: while ((ch = getopt(ac, av, "cdksa:t:")) != -1) {
1.21 markus 1051: switch (ch) {
1052: case 'c':
1053: if (s_flag)
1054: usage();
1055: c_flag++;
1056: break;
1057: case 'k':
1058: k_flag++;
1059: break;
1060: case 's':
1061: if (c_flag)
1062: usage();
1063: s_flag++;
1064: break;
1.57 markus 1065: case 'd':
1066: if (d_flag)
1067: usage();
1068: d_flag++;
1069: break;
1.86 markus 1070: case 'a':
1071: agentsocket = optarg;
1.106 marc 1072: break;
1073: case 't':
1074: if ((lifetime = convtime(optarg)) == -1) {
1075: fprintf(stderr, "Invalid lifetime\n");
1076: usage();
1077: }
1.86 markus 1078: break;
1.21 markus 1079: default:
1080: usage();
1081: }
1082: }
1083: ac -= optind;
1084: av += optind;
1085:
1.57 markus 1086: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 1087: usage();
1088:
1.85 markus 1089: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1090: shell = getenv("SHELL");
1.161 tobias 1091: if (shell != NULL && (len = strlen(shell)) > 2 &&
1092: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1093: c_flag = 1;
1094: }
1095: if (k_flag) {
1.136 deraadt 1096: const char *errstr = NULL;
1097:
1.21 markus 1098: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1099: if (pidstr == NULL) {
1100: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1101: SSH_AGENTPID_ENV_NAME);
1.21 markus 1102: exit(1);
1103: }
1.136 deraadt 1104: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1105: if (errstr) {
1106: fprintf(stderr,
1107: "%s=\"%s\", which is not a good PID: %s\n",
1108: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1109: exit(1);
1110: }
1111: if (kill(pid, SIGTERM) == -1) {
1112: perror("kill");
1113: exit(1);
1114: }
1115: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1116: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1117: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1118: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1119: exit(0);
1120: }
1121: parent_pid = getpid();
1122:
1.86 markus 1123: if (agentsocket == NULL) {
1124: /* Create private directory for agent socket */
1.115 markus 1125: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXXXX", sizeof socket_dir);
1.86 markus 1126: if (mkdtemp(socket_dir) == NULL) {
1127: perror("mkdtemp: private socket dir");
1128: exit(1);
1129: }
1.91 mpech 1130: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1131: (long)parent_pid);
1.86 markus 1132: } else {
1133: /* Try to use specified agent socket */
1134: socket_dir[0] = '\0';
1135: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1136: }
1137:
1.23 markus 1138: /*
1139: * Create socket early so it will exist before command gets run from
1140: * the parent.
1141: */
1.21 markus 1142: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1143: if (sock < 0) {
1144: perror("socket");
1.121 djm 1145: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1146: cleanup_exit(1);
1147: }
1148: memset(&sunaddr, 0, sizeof(sunaddr));
1149: sunaddr.sun_family = AF_UNIX;
1150: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
1.131 deraadt 1151: if (bind(sock, (struct sockaddr *)&sunaddr, sizeof(sunaddr)) < 0) {
1.21 markus 1152: perror("bind");
1.121 djm 1153: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1154: cleanup_exit(1);
1155: }
1.117 markus 1156: if (listen(sock, SSH_LISTEN_BACKLOG) < 0) {
1.21 markus 1157: perror("listen");
1158: cleanup_exit(1);
1159: }
1.46 markus 1160:
1.23 markus 1161: /*
1162: * Fork, and have the parent execute the command, if any, or present
1163: * the socket data. The child continues as the authentication agent.
1164: */
1.57 markus 1165: if (d_flag) {
1166: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
1167: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1168: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1169: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1170: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.57 markus 1171: goto skip;
1172: }
1.21 markus 1173: pid = fork();
1174: if (pid == -1) {
1175: perror("fork");
1.81 stevesk 1176: cleanup_exit(1);
1.21 markus 1177: }
1178: if (pid != 0) { /* Parent - execute the given command. */
1179: close(sock);
1.91 mpech 1180: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1181: if (ac == 0) {
1182: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1183: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1184: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1185: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1186: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1187: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1188: exit(0);
1189: }
1.36 deraadt 1190: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1191: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1192: perror("setenv");
1193: exit(1);
1194: }
1.21 markus 1195: execvp(av[0], av);
1196: perror(av[0]);
1197: exit(1);
1198: }
1.81 stevesk 1199: /* child */
1200: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1201:
1202: if (setsid() == -1) {
1.81 stevesk 1203: error("setsid: %s", strerror(errno));
1.67 stevesk 1204: cleanup_exit(1);
1205: }
1206:
1207: (void)chdir("/");
1.107 markus 1208: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1209: /* XXX might close listen socket */
1210: (void)dup2(fd, STDIN_FILENO);
1211: (void)dup2(fd, STDOUT_FILENO);
1212: (void)dup2(fd, STDERR_FILENO);
1213: if (fd > 2)
1214: close(fd);
1215: }
1.21 markus 1216:
1.41 markus 1217: /* deny core dumps, since memory contains unencrypted private keys */
1218: rlim.rlim_cur = rlim.rlim_max = 0;
1219: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1220: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1221: cleanup_exit(1);
1222: }
1.57 markus 1223:
1224: skip:
1.21 markus 1225: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 1226: if (ac > 0)
1227: parent_alive_interval = 10;
1.33 markus 1228: idtab_init();
1.61 markus 1229: if (!d_flag)
1.57 markus 1230: signal(SIGINT, SIG_IGN);
1.61 markus 1231: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1232: signal(SIGHUP, cleanup_handler);
1233: signal(SIGTERM, cleanup_handler);
1.66 markus 1234: nalloc = 0;
1235:
1.21 markus 1236: while (1) {
1.155 dtucker 1237: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
1238: result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
1.154 dtucker 1239: saved_errno = errno;
1.155 dtucker 1240: if (parent_alive_interval != 0)
1241: check_parent_exists();
1242: (void) reaper(); /* remove expired keys */
1.154 dtucker 1243: if (result < 0) {
1244: if (saved_errno == EINTR)
1.21 markus 1245: continue;
1.154 dtucker 1246: fatal("select: %s", strerror(saved_errno));
1247: } else if (result > 0)
1248: after_select(readsetp, writesetp);
1.15 markus 1249: }
1.21 markus 1250: /* NOTREACHED */
1.1 deraadt 1251: }
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