Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.225
1.225 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.224 2017/07/24 04:34:28 djm 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>
1.141 stevesk 41: #include <sys/socket.h>
1.189 djm 42: #include <sys/stat.h>
1.128 stevesk 43: #include <sys/un.h>
1.126 stevesk 44:
1.185 markus 45: #ifdef WITH_OPENSSL
1.146 stevesk 46: #include <openssl/evp.h>
1.185 markus 47: #endif
1.146 stevesk 48:
1.143 stevesk 49: #include <errno.h>
1.142 stevesk 50: #include <fcntl.h>
1.126 stevesk 51: #include <paths.h>
1.223 djm 52: #include <poll.h>
1.129 stevesk 53: #include <signal.h>
1.149 stevesk 54: #include <stdlib.h>
1.150 stevesk 55: #include <stdio.h>
1.146 stevesk 56: #include <string.h>
1.196 deraadt 57: #include <limits.h>
1.145 stevesk 58: #include <time.h>
1.144 stevesk 59: #include <unistd.h>
1.203 dtucker 60: #include <util.h>
1.194 markus 61:
1.151 deraadt 62: #include "xmalloc.h"
1.1 deraadt 63: #include "ssh.h"
1.194 markus 64: #include "sshbuf.h"
65: #include "sshkey.h"
1.32 markus 66: #include "authfd.h"
1.37 markus 67: #include "compat.h"
1.47 markus 68: #include "log.h"
1.107 markus 69: #include "misc.h"
1.182 markus 70: #include "digest.h"
1.194 markus 71: #include "ssherr.h"
1.215 djm 72: #include "match.h"
1.7 deraadt 73:
1.163 markus 74: #ifdef ENABLE_PKCS11
75: #include "ssh-pkcs11.h"
1.71 jakob 76: #endif
1.59 markus 77:
1.215 djm 78: #ifndef DEFAULT_PKCS11_WHITELIST
1.216 djm 79: # define DEFAULT_PKCS11_WHITELIST "/usr/lib*/*,/usr/local/lib*/*"
1.215 djm 80: #endif
81:
1.223 djm 82: /* Maximum accepted message length */
83: #define AGENT_MAX_LEN (256*1024)
84:
1.73 stevesk 85: typedef enum {
86: AUTH_UNUSED,
87: AUTH_SOCKET,
88: AUTH_CONNECTION
89: } sock_type;
90:
1.21 markus 91: typedef struct {
92: int fd;
1.73 stevesk 93: sock_type type;
1.194 markus 94: struct sshbuf *input;
95: struct sshbuf *output;
96: struct sshbuf *request;
1.1 deraadt 97: } SocketEntry;
98:
1.45 markus 99: u_int sockets_alloc = 0;
1.1 deraadt 100: SocketEntry *sockets = NULL;
101:
1.78 provos 102: typedef struct identity {
103: TAILQ_ENTRY(identity) next;
1.194 markus 104: struct sshkey *key;
1.21 markus 105: char *comment;
1.163 markus 106: char *provider;
1.174 dtucker 107: time_t death;
1.107 markus 108: u_int confirm;
1.1 deraadt 109: } Identity;
110:
1.221 djm 111: struct idtable {
1.33 markus 112: int nentries;
1.78 provos 113: TAILQ_HEAD(idqueue, identity) idlist;
1.221 djm 114: };
1.33 markus 115:
1.221 djm 116: /* private key table */
117: struct idtable *idtab;
1.1 deraadt 118:
119: int max_fd = 0;
120:
1.11 markus 121: /* pid of shell == parent of agent */
1.29 deraadt 122: pid_t parent_pid = -1;
1.176 dtucker 123: time_t parent_alive_interval = 0;
1.10 markus 124:
1.187 djm 125: /* pid of process for which cleanup_socket is applicable */
126: pid_t cleanup_pid = 0;
127:
1.10 markus 128: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 129: char socket_name[PATH_MAX];
130: char socket_dir[PATH_MAX];
1.10 markus 131:
1.215 djm 132: /* PKCS#11 path whitelist */
133: static char *pkcs11_whitelist;
134:
1.88 markus 135: /* locking */
1.203 dtucker 136: #define LOCK_SIZE 32
137: #define LOCK_SALT_SIZE 16
138: #define LOCK_ROUNDS 1
1.88 markus 139: int locked = 0;
1.213 djm 140: u_char lock_pwhash[LOCK_SIZE];
141: u_char lock_salt[LOCK_SALT_SIZE];
1.88 markus 142:
1.20 markus 143: extern char *__progname;
144:
1.174 dtucker 145: /* Default lifetime in seconds (0 == forever) */
146: static long lifetime = 0;
1.106 marc 147:
1.192 djm 148: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
149:
1.55 itojun 150: static void
1.101 stevesk 151: close_socket(SocketEntry *e)
152: {
153: close(e->fd);
154: e->fd = -1;
155: e->type = AUTH_UNUSED;
1.194 markus 156: sshbuf_free(e->input);
157: sshbuf_free(e->output);
158: sshbuf_free(e->request);
1.101 stevesk 159: }
160:
161: static void
1.33 markus 162: idtab_init(void)
1.1 deraadt 163: {
1.221 djm 164: idtab = xcalloc(1, sizeof(*idtab));
165: TAILQ_INIT(&idtab->idlist);
166: idtab->nentries = 0;
1.33 markus 167: }
168:
1.89 markus 169: static void
170: free_identity(Identity *id)
171: {
1.194 markus 172: sshkey_free(id->key);
1.173 djm 173: free(id->provider);
174: free(id->comment);
175: free(id);
1.89 markus 176: }
177:
1.33 markus 178: /* return matching private key for given public key */
1.78 provos 179: static Identity *
1.221 djm 180: lookup_identity(struct sshkey *key)
1.33 markus 181: {
1.78 provos 182: Identity *id;
183:
1.221 djm 184: TAILQ_FOREACH(id, &idtab->idlist, next) {
1.194 markus 185: if (sshkey_equal(key, id->key))
1.78 provos 186: return (id);
1.33 markus 187: }
1.78 provos 188: return (NULL);
189: }
190:
1.107 markus 191: /* Check confirmation of keysign request */
192: static int
193: confirm_key(Identity *id)
194: {
1.122 djm 195: char *p;
1.107 markus 196: int ret = -1;
197:
1.194 markus 198: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 199: if (p != NULL &&
200: ask_permission("Allow use of key %s?\nKey fingerprint %s.",
1.122 djm 201: id->comment, p))
202: ret = 0;
1.173 djm 203: free(p);
1.122 djm 204:
1.107 markus 205: return (ret);
206: }
207:
1.194 markus 208: static void
209: send_status(SocketEntry *e, int success)
210: {
211: int r;
212:
213: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
214: (r = sshbuf_put_u8(e->output, success ?
215: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
216: fatal("%s: buffer error: %s", __func__, ssh_err(r));
217: }
218:
1.33 markus 219: /* send list of supported public keys to 'client' */
1.55 itojun 220: static void
1.221 djm 221: process_request_identities(SocketEntry *e)
1.33 markus 222: {
1.96 deraadt 223: Identity *id;
1.194 markus 224: struct sshbuf *msg;
225: int r;
1.1 deraadt 226:
1.194 markus 227: if ((msg = sshbuf_new()) == NULL)
228: fatal("%s: sshbuf_new failed", __func__);
1.221 djm 229: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
230: (r = sshbuf_put_u32(msg, idtab->nentries)) != 0)
231: fatal("%s: buffer error: %s", __func__, ssh_err(r));
232: TAILQ_FOREACH(id, &idtab->idlist, next) {
233: if ((r = sshkey_puts(id->key, msg)) != 0 ||
234: (r = sshbuf_put_cstring(msg, id->comment)) != 0) {
235: error("%s: put key/comment: %s", __func__,
1.220 djm 236: ssh_err(r));
237: continue;
1.33 markus 238: }
1.21 markus 239: }
1.194 markus 240: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
241: fatal("%s: buffer error: %s", __func__, ssh_err(r));
242: sshbuf_free(msg);
1.1 deraadt 243: }
244:
1.33 markus 245:
1.208 markus 246: static char *
247: agent_decode_alg(struct sshkey *key, u_int flags)
248: {
249: if (key->type == KEY_RSA) {
250: if (flags & SSH_AGENT_RSA_SHA2_256)
251: return "rsa-sha2-256";
252: else if (flags & SSH_AGENT_RSA_SHA2_512)
253: return "rsa-sha2-512";
254: }
255: return NULL;
256: }
257:
1.33 markus 258: /* ssh2 only */
1.55 itojun 259: static void
1.33 markus 260: process_sign_request2(SocketEntry *e)
261: {
1.221 djm 262: const u_char *data;
263: u_char *signature = NULL;
264: size_t dlen, slen = 0;
1.194 markus 265: u_int compat = 0, flags;
266: int r, ok = -1;
267: struct sshbuf *msg;
1.221 djm 268: struct sshkey *key = NULL;
1.195 djm 269: struct identity *id;
1.194 markus 270:
1.195 djm 271: if ((msg = sshbuf_new()) == NULL)
272: fatal("%s: sshbuf_new failed", __func__);
1.221 djm 273: if ((r = sshkey_froms(e->request, &key)) != 0 ||
274: (r = sshbuf_get_string_direct(e->request, &data, &dlen)) != 0 ||
1.225 ! djm 275: (r = sshbuf_get_u32(e->request, &flags)) != 0) {
! 276: error("%s: couldn't parse request: %s", __func__, ssh_err(r));
! 277: goto send;
! 278: }
! 279:
1.37 markus 280: if (flags & SSH_AGENT_OLD_SIGNATURE)
1.194 markus 281: compat = SSH_BUG_SIGBLOB;
1.221 djm 282: if ((id = lookup_identity(key)) == NULL) {
1.195 djm 283: verbose("%s: %s key not found", __func__, sshkey_type(key));
284: goto send;
285: }
286: if (id->confirm && confirm_key(id) != 0) {
287: verbose("%s: user refused key", __func__);
288: goto send;
289: }
290: if ((r = sshkey_sign(id->key, &signature, &slen,
1.208 markus 291: data, dlen, agent_decode_alg(key, flags), compat)) != 0) {
1.209 djm 292: error("%s: sshkey_sign: %s", __func__, ssh_err(r));
1.195 djm 293: goto send;
1.33 markus 294: }
1.195 djm 295: /* Success */
296: ok = 0;
297: send:
298: sshkey_free(key);
1.33 markus 299: if (ok == 0) {
1.194 markus 300: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
301: (r = sshbuf_put_string(msg, signature, slen)) != 0)
302: fatal("%s: buffer error: %s", __func__, ssh_err(r));
303: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
304: fatal("%s: buffer error: %s", __func__, ssh_err(r));
305:
306: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
307: fatal("%s: buffer error: %s", __func__, ssh_err(r));
308:
309: sshbuf_free(msg);
1.173 djm 310: free(signature);
1.1 deraadt 311: }
312:
1.33 markus 313: /* shared */
1.55 itojun 314: static void
1.221 djm 315: process_remove_identity(SocketEntry *e)
1.1 deraadt 316: {
1.194 markus 317: int r, success = 0;
318: struct sshkey *key = NULL;
1.221 djm 319: Identity *id;
1.21 markus 320:
1.221 djm 321: if ((r = sshkey_froms(e->request, &key)) != 0) {
322: error("%s: get key: %s", __func__, ssh_err(r));
323: goto done;
324: }
325: if ((id = lookup_identity(key)) == NULL) {
326: debug("%s: key not found", __func__);
327: goto done;
328: }
329: /* We have this key, free it. */
330: if (idtab->nentries < 1)
331: fatal("%s: internal error: nentries %d",
332: __func__, idtab->nentries);
333: TAILQ_REMOVE(&idtab->idlist, id, next);
334: free_identity(id);
335: idtab->nentries--;
336: sshkey_free(key);
337: success = 1;
338: done:
1.194 markus 339: send_status(e, success);
1.1 deraadt 340: }
341:
1.55 itojun 342: static void
1.221 djm 343: process_remove_all_identities(SocketEntry *e)
1.1 deraadt 344: {
1.78 provos 345: Identity *id;
1.21 markus 346:
347: /* Loop over all identities and clear the keys. */
1.221 djm 348: for (id = TAILQ_FIRST(&idtab->idlist); id;
349: id = TAILQ_FIRST(&idtab->idlist)) {
350: TAILQ_REMOVE(&idtab->idlist, id, next);
1.78 provos 351: free_identity(id);
1.21 markus 352: }
353:
354: /* Mark that there are no identities. */
1.221 djm 355: idtab->nentries = 0;
1.21 markus 356:
357: /* Send success. */
1.194 markus 358: send_status(e, 1);
1.1 deraadt 359: }
360:
1.155 dtucker 361: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 362: static time_t
1.89 markus 363: reaper(void)
364: {
1.175 dtucker 365: time_t deadline = 0, now = monotime();
1.89 markus 366: Identity *id, *nxt;
367:
1.221 djm 368: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
369: nxt = TAILQ_NEXT(id, next);
370: if (id->death == 0)
371: continue;
372: if (now >= id->death) {
373: debug("expiring key '%s'", id->comment);
374: TAILQ_REMOVE(&idtab->idlist, id, next);
375: free_identity(id);
376: idtab->nentries--;
377: } else
378: deadline = (deadline == 0) ? id->death :
379: MINIMUM(deadline, id->death);
1.89 markus 380: }
1.155 dtucker 381: if (deadline == 0 || deadline <= now)
382: return 0;
383: else
384: return (deadline - now);
1.89 markus 385: }
386:
387: static void
1.221 djm 388: process_add_identity(SocketEntry *e)
1.1 deraadt 389: {
1.157 canacar 390: Identity *id;
1.194 markus 391: int success = 0, confirm = 0;
392: u_int seconds;
393: char *comment = NULL;
1.174 dtucker 394: time_t death = 0;
1.194 markus 395: struct sshkey *k = NULL;
396: u_char ctype;
397: int r = SSH_ERR_INTERNAL_ERROR;
1.33 markus 398:
1.221 djm 399: if ((r = sshkey_private_deserialize(e->request, &k)) != 0 ||
400: k == NULL ||
1.194 markus 401: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
402: error("%s: decode private key: %s", __func__, ssh_err(r));
403: goto err;
404: }
1.186 djm 405:
1.194 markus 406: while (sshbuf_len(e->request)) {
407: if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) {
408: error("%s: buffer error: %s", __func__, ssh_err(r));
409: goto err;
410: }
411: switch (ctype) {
1.94 markus 412: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 413: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) {
414: error("%s: bad lifetime constraint: %s",
415: __func__, ssh_err(r));
416: goto err;
417: }
418: death = monotime() + seconds;
1.94 markus 419: break;
1.107 markus 420: case SSH_AGENT_CONSTRAIN_CONFIRM:
421: confirm = 1;
422: break;
1.94 markus 423: default:
1.194 markus 424: error("%s: Unknown constraint %d", __func__, ctype);
425: err:
426: sshbuf_reset(e->request);
1.173 djm 427: free(comment);
1.194 markus 428: sshkey_free(k);
1.158 djm 429: goto send;
1.94 markus 430: }
431: }
1.194 markus 432:
1.158 djm 433: success = 1;
1.106 marc 434: if (lifetime && !death)
1.175 dtucker 435: death = monotime() + lifetime;
1.221 djm 436: if ((id = lookup_identity(k)) == NULL) {
1.163 markus 437: id = xcalloc(1, sizeof(Identity));
1.78 provos 438: id->key = k;
1.221 djm 439: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
1.33 markus 440: /* Increment the number of identities. */
1.221 djm 441: idtab->nentries++;
1.33 markus 442: } else {
1.194 markus 443: sshkey_free(k);
1.173 djm 444: free(id->comment);
1.33 markus 445: }
1.157 canacar 446: id->comment = comment;
447: id->death = death;
448: id->confirm = confirm;
1.33 markus 449: send:
1.194 markus 450: send_status(e, success);
1.1 deraadt 451: }
452:
1.88 markus 453: /* XXX todo: encrypt sensitive data with passphrase */
454: static void
455: process_lock_agent(SocketEntry *e, int lock)
456: {
1.203 dtucker 457: int r, success = 0, delay;
1.213 djm 458: char *passwd;
459: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 460: static u_int fail_count = 0;
461: size_t pwlen;
462:
463: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
464: fatal("%s: buffer error: %s", __func__, ssh_err(r));
465: if (pwlen == 0) {
466: debug("empty password not supported");
467: } else if (locked && !lock) {
468: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
469: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
470: fatal("bcrypt_pbkdf");
1.213 djm 471: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 472: debug("agent unlocked");
473: locked = 0;
474: fail_count = 0;
1.213 djm 475: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 476: success = 1;
477: } else {
478: /* delay in 0.1s increments up to 10s */
479: if (fail_count < 100)
480: fail_count++;
481: delay = 100000 * fail_count;
482: debug("unlock failed, delaying %0.1lf seconds",
483: (double)delay/1000000);
484: usleep(delay);
485: }
486: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 487: } else if (!locked && lock) {
1.203 dtucker 488: debug("agent locked");
1.88 markus 489: locked = 1;
1.203 dtucker 490: arc4random_buf(lock_salt, sizeof(lock_salt));
491: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 djm 492: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 493: fatal("bcrypt_pbkdf");
1.88 markus 494: success = 1;
495: }
1.203 dtucker 496: explicit_bzero(passwd, pwlen);
1.173 djm 497: free(passwd);
1.194 markus 498: send_status(e, success);
1.88 markus 499: }
500:
501: static void
1.221 djm 502: no_identities(SocketEntry *e)
1.88 markus 503: {
1.194 markus 504: struct sshbuf *msg;
505: int r;
1.88 markus 506:
1.194 markus 507: if ((msg = sshbuf_new()) == NULL)
508: fatal("%s: sshbuf_new failed", __func__);
1.221 djm 509: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
1.194 markus 510: (r = sshbuf_put_u32(msg, 0)) != 0 ||
511: (r = sshbuf_put_stringb(e->output, msg)) != 0)
512: fatal("%s: buffer error: %s", __func__, ssh_err(r));
513: sshbuf_free(msg);
1.88 markus 514: }
1.59 markus 515:
1.163 markus 516: #ifdef ENABLE_PKCS11
1.59 markus 517: static void
1.158 djm 518: process_add_smartcard_key(SocketEntry *e)
1.59 markus 519: {
1.215 djm 520: char *provider = NULL, *pin, canonical_provider[PATH_MAX];
1.221 djm 521: int r, i, count = 0, success = 0, confirm = 0;
1.194 markus 522: u_int seconds;
1.174 dtucker 523: time_t death = 0;
1.194 markus 524: u_char type;
525: struct sshkey **keys = NULL, *k;
1.84 markus 526: Identity *id;
1.75 deraadt 527:
1.194 markus 528: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
529: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
530: fatal("%s: buffer error: %s", __func__, ssh_err(r));
531:
532: while (sshbuf_len(e->request)) {
533: if ((r = sshbuf_get_u8(e->request, &type)) != 0)
534: fatal("%s: buffer error: %s", __func__, ssh_err(r));
535: switch (type) {
1.110 djm 536: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 537: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
538: fatal("%s: buffer error: %s",
539: __func__, ssh_err(r));
540: death = monotime() + seconds;
1.110 djm 541: break;
542: case SSH_AGENT_CONSTRAIN_CONFIRM:
543: confirm = 1;
544: break;
545: default:
1.221 djm 546: error("%s: Unknown constraint type %d", __func__, type);
1.158 djm 547: goto send;
1.110 djm 548: }
549: }
1.215 djm 550: if (realpath(provider, canonical_provider) == NULL) {
551: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
552: provider, strerror(errno));
553: goto send;
554: }
555: if (match_pattern_list(canonical_provider, pkcs11_whitelist, 0) != 1) {
556: verbose("refusing PKCS#11 add of \"%.100s\": "
557: "provider not whitelisted", canonical_provider);
558: goto send;
559: }
560: debug("%s: add %.100s", __func__, canonical_provider);
1.110 djm 561: if (lifetime && !death)
1.175 dtucker 562: death = monotime() + lifetime;
1.110 djm 563:
1.215 djm 564: count = pkcs11_add_provider(canonical_provider, pin, &keys);
1.163 markus 565: for (i = 0; i < count; i++) {
1.84 markus 566: k = keys[i];
1.221 djm 567: if (lookup_identity(k) == NULL) {
1.163 markus 568: id = xcalloc(1, sizeof(Identity));
1.84 markus 569: id->key = k;
1.215 djm 570: id->provider = xstrdup(canonical_provider);
571: id->comment = xstrdup(canonical_provider); /* XXX */
1.110 djm 572: id->death = death;
573: id->confirm = confirm;
1.221 djm 574: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
575: idtab->nentries++;
1.84 markus 576: success = 1;
577: } else {
1.194 markus 578: sshkey_free(k);
1.84 markus 579: }
580: keys[i] = NULL;
1.59 markus 581: }
582: send:
1.173 djm 583: free(pin);
584: free(provider);
585: free(keys);
1.194 markus 586: send_status(e, success);
1.59 markus 587: }
588:
589: static void
590: process_remove_smartcard_key(SocketEntry *e)
591: {
1.217 djm 592: char *provider = NULL, *pin = NULL, canonical_provider[PATH_MAX];
1.221 djm 593: int r, success = 0;
1.163 markus 594: Identity *id, *nxt;
1.59 markus 595:
1.194 markus 596: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
597: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
598: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.173 djm 599: free(pin);
1.59 markus 600:
1.217 djm 601: if (realpath(provider, canonical_provider) == NULL) {
602: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
603: provider, strerror(errno));
604: goto send;
605: }
606:
607: debug("%s: remove %.100s", __func__, canonical_provider);
1.221 djm 608: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
609: nxt = TAILQ_NEXT(id, next);
610: /* Skip file--based keys */
611: if (id->provider == NULL)
612: continue;
613: if (!strcmp(canonical_provider, id->provider)) {
614: TAILQ_REMOVE(&idtab->idlist, id, next);
615: free_identity(id);
616: idtab->nentries--;
1.59 markus 617: }
618: }
1.217 djm 619: if (pkcs11_del_provider(canonical_provider) == 0)
1.163 markus 620: success = 1;
621: else
1.221 djm 622: error("%s: pkcs11_del_provider failed", __func__);
1.218 deraadt 623: send:
1.173 djm 624: free(provider);
1.194 markus 625: send_status(e, success);
1.59 markus 626: }
1.163 markus 627: #endif /* ENABLE_PKCS11 */
1.59 markus 628:
1.33 markus 629: /* dispatch incoming messages */
630:
1.223 djm 631: static int
632: process_message(u_int socknum)
1.1 deraadt 633: {
1.194 markus 634: u_int msg_len;
635: u_char type;
636: const u_char *cp;
637: int r;
1.223 djm 638: SocketEntry *e;
639:
640: if (socknum >= sockets_alloc) {
641: fatal("%s: socket number %u >= allocated %u",
642: __func__, socknum, sockets_alloc);
643: }
644: e = &sockets[socknum];
1.89 markus 645:
1.194 markus 646: if (sshbuf_len(e->input) < 5)
1.223 djm 647: return 0; /* Incomplete message header. */
1.194 markus 648: cp = sshbuf_ptr(e->input);
649: msg_len = PEEK_U32(cp);
1.223 djm 650: if (msg_len > AGENT_MAX_LEN) {
651: debug("%s: socket %u (fd=%d) message too long %u > %u",
652: __func__, socknum, e->fd, msg_len, AGENT_MAX_LEN);
653: return -1;
1.21 markus 654: }
1.194 markus 655: if (sshbuf_len(e->input) < msg_len + 4)
1.223 djm 656: return 0; /* Incomplete message body. */
1.87 markus 657:
658: /* move the current input to e->request */
1.194 markus 659: sshbuf_reset(e->request);
660: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
1.223 djm 661: (r = sshbuf_get_u8(e->request, &type)) != 0) {
662: if (r == SSH_ERR_MESSAGE_INCOMPLETE ||
663: r == SSH_ERR_STRING_TOO_LARGE) {
664: debug("%s: buffer error: %s", __func__, ssh_err(r));
665: return -1;
666: }
1.194 markus 667: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.223 djm 668: }
669:
670: debug("%s: socket %u (fd=%d) type %d", __func__, socknum, e->fd, type);
1.21 markus 671:
1.88 markus 672: /* check wheter agent is locked */
673: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 674: sshbuf_reset(e->request);
1.88 markus 675: switch (type) {
676: case SSH2_AGENTC_REQUEST_IDENTITIES:
677: /* send empty lists */
1.221 djm 678: no_identities(e);
1.88 markus 679: break;
680: default:
681: /* send a fail message for all other request types */
1.194 markus 682: send_status(e, 0);
1.88 markus 683: }
1.223 djm 684: return 0;
1.88 markus 685: }
686:
1.21 markus 687: switch (type) {
1.88 markus 688: case SSH_AGENTC_LOCK:
689: case SSH_AGENTC_UNLOCK:
690: process_lock_agent(e, type == SSH_AGENTC_LOCK);
691: break;
1.21 markus 692: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.221 djm 693: process_remove_all_identities(e); /* safe for !WITH_SSH1 */
1.33 markus 694: break;
695: /* ssh2 */
696: case SSH2_AGENTC_SIGN_REQUEST:
697: process_sign_request2(e);
698: break;
699: case SSH2_AGENTC_REQUEST_IDENTITIES:
1.221 djm 700: process_request_identities(e);
1.33 markus 701: break;
702: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 703: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.221 djm 704: process_add_identity(e);
1.33 markus 705: break;
706: case SSH2_AGENTC_REMOVE_IDENTITY:
1.221 djm 707: process_remove_identity(e);
1.33 markus 708: break;
709: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
1.221 djm 710: process_remove_all_identities(e);
1.21 markus 711: break;
1.163 markus 712: #ifdef ENABLE_PKCS11
1.59 markus 713: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 714: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 715: process_add_smartcard_key(e);
1.75 deraadt 716: break;
1.59 markus 717: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
718: process_remove_smartcard_key(e);
1.75 deraadt 719: break;
1.163 markus 720: #endif /* ENABLE_PKCS11 */
1.21 markus 721: default:
722: /* Unknown message. Respond with failure. */
723: error("Unknown message %d", type);
1.194 markus 724: sshbuf_reset(e->request);
725: send_status(e, 0);
1.21 markus 726: break;
727: }
1.223 djm 728: return 0;
1.1 deraadt 729: }
730:
1.55 itojun 731: static void
1.73 stevesk 732: new_socket(sock_type type, int fd)
1.1 deraadt 733: {
1.112 markus 734: u_int i, old_alloc, new_alloc;
1.96 deraadt 735:
1.119 djm 736: set_nonblock(fd);
1.21 markus 737:
738: if (fd > max_fd)
739: max_fd = fd;
740:
741: for (i = 0; i < sockets_alloc; i++)
742: if (sockets[i].type == AUTH_UNUSED) {
743: sockets[i].fd = fd;
1.194 markus 744: if ((sockets[i].input = sshbuf_new()) == NULL)
745: fatal("%s: sshbuf_new failed", __func__);
746: if ((sockets[i].output = sshbuf_new()) == NULL)
747: fatal("%s: sshbuf_new failed", __func__);
748: if ((sockets[i].request = sshbuf_new()) == NULL)
749: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 750: sockets[i].type = type;
1.21 markus 751: return;
752: }
753: old_alloc = sockets_alloc;
1.112 markus 754: new_alloc = sockets_alloc + 10;
1.200 deraadt 755: sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 756: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 757: sockets[i].type = AUTH_UNUSED;
1.112 markus 758: sockets_alloc = new_alloc;
1.21 markus 759: sockets[old_alloc].fd = fd;
1.194 markus 760: if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
761: fatal("%s: sshbuf_new failed", __func__);
762: if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
763: fatal("%s: sshbuf_new failed", __func__);
764: if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
765: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 766: sockets[old_alloc].type = type;
1.1 deraadt 767: }
768:
1.55 itojun 769: static int
1.223 djm 770: handle_socket_read(u_int socknum)
1.1 deraadt 771: {
1.223 djm 772: struct sockaddr_un sunaddr;
773: socklen_t slen;
774: uid_t euid;
775: gid_t egid;
776: int fd;
777:
778: slen = sizeof(sunaddr);
779: fd = accept(sockets[socknum].fd, (struct sockaddr *)&sunaddr, &slen);
780: if (fd < 0) {
781: error("accept from AUTH_SOCKET: %s", strerror(errno));
782: return -1;
783: }
784: if (getpeereid(fd, &euid, &egid) < 0) {
785: error("getpeereid %d failed: %s", fd, strerror(errno));
786: close(fd);
787: return -1;
788: }
789: if ((euid != 0) && (getuid() != euid)) {
790: error("uid mismatch: peer euid %u != uid %u",
791: (u_int) euid, (u_int) getuid());
792: close(fd);
793: return -1;
794: }
795: new_socket(AUTH_CONNECTION, fd);
796: return 0;
797: }
798:
799: static int
800: handle_conn_read(u_int socknum)
801: {
802: char buf[1024];
803: ssize_t len;
804: int r;
805:
806: if ((len = read(sockets[socknum].fd, buf, sizeof(buf))) <= 0) {
807: if (len == -1) {
808: if (errno == EAGAIN || errno == EINTR)
809: return 0;
810: error("%s: read error on socket %u (fd %d): %s",
811: __func__, socknum, sockets[socknum].fd,
812: strerror(errno));
813: }
814: return -1;
815: }
816: if ((r = sshbuf_put(sockets[socknum].input, buf, len)) != 0)
817: fatal("%s: buffer error: %s", __func__, ssh_err(r));
818: explicit_bzero(buf, sizeof(buf));
819: process_message(socknum);
820: return 0;
821: }
822:
823: static int
824: handle_conn_write(u_int socknum)
825: {
826: ssize_t len;
827: int r;
828:
829: if (sshbuf_len(sockets[socknum].output) == 0)
830: return 0; /* shouldn't happen */
831: if ((len = write(sockets[socknum].fd,
832: sshbuf_ptr(sockets[socknum].output),
833: sshbuf_len(sockets[socknum].output))) <= 0) {
834: if (len == -1) {
835: if (errno == EAGAIN || errno == EINTR)
836: return 0;
837: error("%s: read error on socket %u (fd %d): %s",
838: __func__, socknum, sockets[socknum].fd,
839: strerror(errno));
840: }
841: return -1;
842: }
843: if ((r = sshbuf_consume(sockets[socknum].output, len)) != 0)
844: fatal("%s: buffer error: %s", __func__, ssh_err(r));
845: return 0;
846: }
847:
848: static void
849: after_poll(struct pollfd *pfd, size_t npfd)
850: {
851: size_t i;
852: u_int socknum;
853:
854: for (i = 0; i < npfd; i++) {
855: if (pfd[i].revents == 0)
856: continue;
857: /* Find sockets entry */
858: for (socknum = 0; socknum < sockets_alloc; socknum++) {
859: if (sockets[socknum].type != AUTH_SOCKET &&
860: sockets[socknum].type != AUTH_CONNECTION)
861: continue;
862: if (pfd[i].fd == sockets[socknum].fd)
863: break;
864: }
865: if (socknum >= sockets_alloc) {
866: error("%s: no socket for fd %d", __func__, pfd[i].fd);
867: continue;
868: }
869: /* Process events */
870: switch (sockets[socknum].type) {
871: case AUTH_SOCKET:
872: if ((pfd[i].revents & (POLLIN|POLLERR)) != 0 &&
873: handle_socket_read(socknum) != 0)
874: close_socket(&sockets[socknum]);
875: break;
876: case AUTH_CONNECTION:
877: if ((pfd[i].revents & (POLLIN|POLLERR)) != 0 &&
878: handle_conn_read(socknum) != 0) {
879: close_socket(&sockets[socknum]);
880: break;
881: }
882: if ((pfd[i].revents & (POLLOUT|POLLHUP)) != 0 &&
883: handle_conn_write(socknum) != 0)
884: close_socket(&sockets[socknum]);
885: break;
886: default:
887: break;
888: }
889: }
890: }
891:
892: static int
893: prepare_poll(struct pollfd **pfdp, size_t *npfdp, int *timeoutp)
894: {
895: struct pollfd *pfd = *pfdp;
896: size_t i, j, npfd = 0;
1.174 dtucker 897: time_t deadline;
1.46 markus 898:
1.223 djm 899: /* Count active sockets */
1.46 markus 900: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 901: switch (sockets[i].type) {
902: case AUTH_SOCKET:
903: case AUTH_CONNECTION:
1.223 djm 904: npfd++;
1.21 markus 905: break;
906: case AUTH_UNUSED:
907: break;
908: default:
909: fatal("Unknown socket type %d", sockets[i].type);
910: break;
911: }
1.46 markus 912: }
1.223 djm 913: if (npfd != *npfdp &&
914: (pfd = recallocarray(pfd, *npfdp, npfd, sizeof(*pfd))) == NULL)
915: fatal("%s: recallocarray failed", __func__);
916: *pfdp = pfd;
917: *npfdp = npfd;
1.46 markus 918:
1.223 djm 919: for (i = j = 0; i < sockets_alloc; i++) {
1.46 markus 920: switch (sockets[i].type) {
921: case AUTH_SOCKET:
922: case AUTH_CONNECTION:
1.223 djm 923: pfd[j].fd = sockets[i].fd;
924: pfd[j].revents = 0;
925: /* XXX backoff when input buffer full */
926: pfd[j].events = POLLIN;
1.194 markus 927: if (sshbuf_len(sockets[i].output) > 0)
1.223 djm 928: pfd[j].events |= POLLOUT;
929: j++;
1.46 markus 930: break;
931: default:
932: break;
933: }
934: }
1.155 dtucker 935: deadline = reaper();
936: if (parent_alive_interval != 0)
937: deadline = (deadline == 0) ? parent_alive_interval :
1.214 deraadt 938: MINIMUM(deadline, parent_alive_interval);
1.155 dtucker 939: if (deadline == 0) {
1.224 djm 940: *timeoutp = -1; /* INFTIM */
1.155 dtucker 941: } else {
1.223 djm 942: if (deadline > INT_MAX / 1000)
943: *timeoutp = INT_MAX / 1000;
944: else
945: *timeoutp = deadline * 1000;
1.155 dtucker 946: }
1.46 markus 947: return (1);
1.21 markus 948: }
949:
1.55 itojun 950: static void
1.113 markus 951: cleanup_socket(void)
1.15 markus 952: {
1.187 djm 953: if (cleanup_pid != 0 && getpid() != cleanup_pid)
954: return;
955: debug("%s: cleanup", __func__);
1.48 deraadt 956: if (socket_name[0])
957: unlink(socket_name);
958: if (socket_dir[0])
959: rmdir(socket_dir);
1.10 markus 960: }
961:
1.114 markus 962: void
1.15 markus 963: cleanup_exit(int i)
964: {
1.113 markus 965: cleanup_socket();
966: _exit(i);
1.15 markus 967: }
968:
1.135 deraadt 969: /*ARGSUSED*/
1.55 itojun 970: static void
1.48 deraadt 971: cleanup_handler(int sig)
972: {
1.113 markus 973: cleanup_socket();
1.163 markus 974: #ifdef ENABLE_PKCS11
975: pkcs11_terminate();
976: #endif
1.48 deraadt 977: _exit(2);
1.113 markus 978: }
979:
1.68 markus 980: static void
1.155 dtucker 981: check_parent_exists(void)
1.68 markus 982: {
1.172 dtucker 983: /*
984: * If our parent has exited then getppid() will return (pid_t)1,
985: * so testing for that should be safe.
986: */
987: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 988: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 989: cleanup_socket();
990: _exit(2);
1.68 markus 991: }
1.48 deraadt 992: }
993:
1.55 itojun 994: static void
1.50 itojun 995: usage(void)
1.15 markus 996: {
1.184 deraadt 997: fprintf(stderr,
1.202 jmc 998: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.215 djm 999: " [-P pkcs11_whitelist] [-t life] [command [arg ...]]\n"
1.184 deraadt 1000: " ssh-agent [-c | -s] -k\n");
1.21 markus 1001: exit(1);
1.15 markus 1002: }
1003:
1.2 provos 1004: int
1005: main(int ac, char **av)
1.1 deraadt 1006: {
1.201 djm 1007: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1008: int sock, fd, ch, result, saved_errno;
1.96 deraadt 1009: char *shell, *format, *pidstr, *agentsocket = NULL;
1.41 markus 1010: struct rlimit rlim;
1.96 deraadt 1011: extern int optind;
1.98 stevesk 1012: extern char *optarg;
1.21 markus 1013: pid_t pid;
1.96 deraadt 1014: char pidstrbuf[1 + 3 * sizeof pid];
1.161 tobias 1015: size_t len;
1.189 djm 1016: mode_t prev_mask;
1.224 djm 1017: int timeout = -1; /* INFTIM */
1.223 djm 1018: struct pollfd *pfd = NULL;
1019: size_t npfd = 0;
1.123 djm 1020:
1.212 dtucker 1021: ssh_malloc_init(); /* must be called before any mallocs */
1.123 djm 1022: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1023: sanitise_stdfd();
1.99 markus 1024:
1025: /* drop */
1026: setegid(getgid());
1027: setgid(getgid());
1.53 markus 1028:
1.185 markus 1029: #ifdef WITH_OPENSSL
1.170 djm 1030: OpenSSL_add_all_algorithms();
1.185 markus 1031: #endif
1.21 markus 1032:
1.215 djm 1033: while ((ch = getopt(ac, av, "cDdksE:a:P:t:")) != -1) {
1.21 markus 1034: switch (ch) {
1.192 djm 1035: case 'E':
1036: fingerprint_hash = ssh_digest_alg_by_name(optarg);
1037: if (fingerprint_hash == -1)
1038: fatal("Invalid hash algorithm \"%s\"", optarg);
1039: break;
1.21 markus 1040: case 'c':
1041: if (s_flag)
1042: usage();
1043: c_flag++;
1044: break;
1045: case 'k':
1046: k_flag++;
1047: break;
1.215 djm 1048: case 'P':
1049: if (pkcs11_whitelist != NULL)
1050: fatal("-P option already specified");
1051: pkcs11_whitelist = xstrdup(optarg);
1052: break;
1.21 markus 1053: case 's':
1054: if (c_flag)
1055: usage();
1056: s_flag++;
1057: break;
1.57 markus 1058: case 'd':
1.201 djm 1059: if (d_flag || D_flag)
1.57 markus 1060: usage();
1061: d_flag++;
1062: break;
1.201 djm 1063: case 'D':
1064: if (d_flag || D_flag)
1065: usage();
1066: D_flag++;
1067: break;
1.86 markus 1068: case 'a':
1069: agentsocket = optarg;
1.106 marc 1070: break;
1071: case 't':
1072: if ((lifetime = convtime(optarg)) == -1) {
1073: fprintf(stderr, "Invalid lifetime\n");
1074: usage();
1075: }
1.86 markus 1076: break;
1.21 markus 1077: default:
1078: usage();
1079: }
1080: }
1081: ac -= optind;
1082: av += optind;
1083:
1.201 djm 1084: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 1085: usage();
1086:
1.215 djm 1087: if (pkcs11_whitelist == NULL)
1088: pkcs11_whitelist = xstrdup(DEFAULT_PKCS11_WHITELIST);
1089:
1.85 markus 1090: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1091: shell = getenv("SHELL");
1.161 tobias 1092: if (shell != NULL && (len = strlen(shell)) > 2 &&
1093: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1094: c_flag = 1;
1095: }
1096: if (k_flag) {
1.136 deraadt 1097: const char *errstr = NULL;
1098:
1.21 markus 1099: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1100: if (pidstr == NULL) {
1101: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1102: SSH_AGENTPID_ENV_NAME);
1.21 markus 1103: exit(1);
1104: }
1.136 deraadt 1105: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1106: if (errstr) {
1107: fprintf(stderr,
1108: "%s=\"%s\", which is not a good PID: %s\n",
1109: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1110: exit(1);
1111: }
1112: if (kill(pid, SIGTERM) == -1) {
1113: perror("kill");
1114: exit(1);
1115: }
1116: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1117: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1118: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1119: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1120: exit(0);
1121: }
1122: parent_pid = getpid();
1123:
1.86 markus 1124: if (agentsocket == NULL) {
1125: /* Create private directory for agent socket */
1.171 djm 1126: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 1127: if (mkdtemp(socket_dir) == NULL) {
1128: perror("mkdtemp: private socket dir");
1129: exit(1);
1130: }
1.91 mpech 1131: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1132: (long)parent_pid);
1.86 markus 1133: } else {
1134: /* Try to use specified agent socket */
1135: socket_dir[0] = '\0';
1136: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1137: }
1138:
1.23 markus 1139: /*
1140: * Create socket early so it will exist before command gets run from
1141: * the parent.
1142: */
1.189 djm 1143: prev_mask = umask(0177);
1.188 millert 1144: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 1145: if (sock < 0) {
1.188 millert 1146: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 1147: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1148: cleanup_exit(1);
1149: }
1.189 djm 1150: umask(prev_mask);
1.46 markus 1151:
1.23 markus 1152: /*
1153: * Fork, and have the parent execute the command, if any, or present
1154: * the socket data. The child continues as the authentication agent.
1155: */
1.201 djm 1156: if (D_flag || d_flag) {
1157: log_init(__progname,
1158: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
1159: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 1160: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1161: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1162: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1163: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 1164: fflush(stdout);
1.57 markus 1165: goto skip;
1166: }
1.21 markus 1167: pid = fork();
1168: if (pid == -1) {
1169: perror("fork");
1.81 stevesk 1170: cleanup_exit(1);
1.21 markus 1171: }
1172: if (pid != 0) { /* Parent - execute the given command. */
1173: close(sock);
1.91 mpech 1174: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1175: if (ac == 0) {
1176: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1177: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1178: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1179: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1180: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1181: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1182: exit(0);
1183: }
1.36 deraadt 1184: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1185: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1186: perror("setenv");
1187: exit(1);
1188: }
1.21 markus 1189: execvp(av[0], av);
1190: perror(av[0]);
1191: exit(1);
1192: }
1.81 stevesk 1193: /* child */
1194: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1195:
1196: if (setsid() == -1) {
1.81 stevesk 1197: error("setsid: %s", strerror(errno));
1.67 stevesk 1198: cleanup_exit(1);
1199: }
1200:
1201: (void)chdir("/");
1.107 markus 1202: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1203: /* XXX might close listen socket */
1204: (void)dup2(fd, STDIN_FILENO);
1205: (void)dup2(fd, STDOUT_FILENO);
1206: (void)dup2(fd, STDERR_FILENO);
1207: if (fd > 2)
1208: close(fd);
1209: }
1.21 markus 1210:
1.41 markus 1211: /* deny core dumps, since memory contains unencrypted private keys */
1212: rlim.rlim_cur = rlim.rlim_max = 0;
1213: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1214: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1215: cleanup_exit(1);
1216: }
1.57 markus 1217:
1218: skip:
1.187 djm 1219:
1220: cleanup_pid = getpid();
1.163 markus 1221:
1222: #ifdef ENABLE_PKCS11
1223: pkcs11_init(0);
1224: #endif
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: signal(SIGPIPE, SIG_IGN);
1.201 djm 1230: signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
1.48 deraadt 1231: signal(SIGHUP, cleanup_handler);
1232: signal(SIGTERM, cleanup_handler);
1.205 djm 1233:
1.215 djm 1234: if (pledge("stdio rpath cpath unix id proc exec", NULL) == -1)
1.205 djm 1235: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 1236:
1.21 markus 1237: while (1) {
1.223 djm 1238: prepare_poll(&pfd, &npfd, &timeout);
1239: result = poll(pfd, npfd, timeout);
1.154 dtucker 1240: saved_errno = errno;
1.155 dtucker 1241: if (parent_alive_interval != 0)
1242: check_parent_exists();
1243: (void) reaper(); /* remove expired keys */
1.154 dtucker 1244: if (result < 0) {
1245: if (saved_errno == EINTR)
1.21 markus 1246: continue;
1.223 djm 1247: fatal("poll: %s", strerror(saved_errno));
1.154 dtucker 1248: } else if (result > 0)
1.223 djm 1249: after_poll(pfd, npfd);
1.15 markus 1250: }
1.21 markus 1251: /* NOTREACHED */
1.1 deraadt 1252: }
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