Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.208
1.208 ! markus 1: /* $OpenBSD: ssh-agent.c,v 1.207 2015/12/02 08:30:50 doug 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:
1.196 deraadt 37: #include <sys/param.h> /* MIN MAX */
1.151 deraadt 38: #include <sys/types.h>
1.153 djm 39: #include <sys/time.h>
1.78 provos 40: #include <sys/queue.h>
1.127 stevesk 41: #include <sys/resource.h>
1.141 stevesk 42: #include <sys/socket.h>
1.189 djm 43: #include <sys/stat.h>
1.128 stevesk 44: #include <sys/un.h>
1.126 stevesk 45:
1.185 markus 46: #ifdef WITH_OPENSSL
1.146 stevesk 47: #include <openssl/evp.h>
1.185 markus 48: #endif
1.146 stevesk 49:
1.143 stevesk 50: #include <errno.h>
1.142 stevesk 51: #include <fcntl.h>
1.126 stevesk 52: #include <paths.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"
64: #include "rsa.h"
1.194 markus 65: #include "sshbuf.h"
66: #include "sshkey.h"
1.32 markus 67: #include "authfd.h"
1.37 markus 68: #include "compat.h"
1.47 markus 69: #include "log.h"
1.107 markus 70: #include "misc.h"
1.182 markus 71: #include "digest.h"
1.194 markus 72: #include "ssherr.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:
1.73 stevesk 78: typedef enum {
79: AUTH_UNUSED,
80: AUTH_SOCKET,
81: AUTH_CONNECTION
82: } sock_type;
83:
1.21 markus 84: typedef struct {
85: int fd;
1.73 stevesk 86: sock_type type;
1.194 markus 87: struct sshbuf *input;
88: struct sshbuf *output;
89: struct sshbuf *request;
1.1 deraadt 90: } SocketEntry;
91:
1.45 markus 92: u_int sockets_alloc = 0;
1.1 deraadt 93: SocketEntry *sockets = NULL;
94:
1.78 provos 95: typedef struct identity {
96: TAILQ_ENTRY(identity) next;
1.194 markus 97: struct sshkey *key;
1.21 markus 98: char *comment;
1.163 markus 99: char *provider;
1.174 dtucker 100: time_t death;
1.107 markus 101: u_int confirm;
1.1 deraadt 102: } Identity;
103:
1.33 markus 104: typedef struct {
105: int nentries;
1.78 provos 106: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 107: } Idtab;
108:
109: /* private key table, one per protocol version */
110: Idtab idtable[3];
1.1 deraadt 111:
112: int max_fd = 0;
113:
1.11 markus 114: /* pid of shell == parent of agent */
1.29 deraadt 115: pid_t parent_pid = -1;
1.176 dtucker 116: time_t parent_alive_interval = 0;
1.10 markus 117:
1.187 djm 118: /* pid of process for which cleanup_socket is applicable */
119: pid_t cleanup_pid = 0;
120:
1.10 markus 121: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 122: char socket_name[PATH_MAX];
123: char socket_dir[PATH_MAX];
1.10 markus 124:
1.88 markus 125: /* locking */
1.203 dtucker 126: #define LOCK_SIZE 32
127: #define LOCK_SALT_SIZE 16
128: #define LOCK_ROUNDS 1
1.88 markus 129: int locked = 0;
1.203 dtucker 130: char lock_passwd[LOCK_SIZE];
131: char lock_salt[LOCK_SALT_SIZE];
1.88 markus 132:
1.20 markus 133: extern char *__progname;
134:
1.174 dtucker 135: /* Default lifetime in seconds (0 == forever) */
136: static long lifetime = 0;
1.106 marc 137:
1.192 djm 138: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
139:
1.55 itojun 140: static void
1.101 stevesk 141: close_socket(SocketEntry *e)
142: {
143: close(e->fd);
144: e->fd = -1;
145: e->type = AUTH_UNUSED;
1.194 markus 146: sshbuf_free(e->input);
147: sshbuf_free(e->output);
148: sshbuf_free(e->request);
1.101 stevesk 149: }
150:
151: static void
1.33 markus 152: idtab_init(void)
1.1 deraadt 153: {
1.33 markus 154: int i;
1.96 deraadt 155:
1.74 deraadt 156: for (i = 0; i <=2; i++) {
1.78 provos 157: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 158: idtable[i].nentries = 0;
159: }
160: }
161:
162: /* return private key table for requested protocol version */
1.55 itojun 163: static Idtab *
1.33 markus 164: idtab_lookup(int version)
165: {
166: if (version < 1 || version > 2)
167: fatal("internal error, bad protocol version %d", version);
168: return &idtable[version];
169: }
170:
1.89 markus 171: static void
172: free_identity(Identity *id)
173: {
1.194 markus 174: sshkey_free(id->key);
1.173 djm 175: free(id->provider);
176: free(id->comment);
177: free(id);
1.89 markus 178: }
179:
1.33 markus 180: /* return matching private key for given public key */
1.78 provos 181: static Identity *
1.194 markus 182: lookup_identity(struct sshkey *key, int version)
1.33 markus 183: {
1.78 provos 184: Identity *id;
185:
1.33 markus 186: Idtab *tab = idtab_lookup(version);
1.78 provos 187: TAILQ_FOREACH(id, &tab->idlist, next) {
1.194 markus 188: if (sshkey_equal(key, id->key))
1.78 provos 189: return (id);
1.33 markus 190: }
1.78 provos 191: return (NULL);
192: }
193:
1.107 markus 194: /* Check confirmation of keysign request */
195: static int
196: confirm_key(Identity *id)
197: {
1.122 djm 198: char *p;
1.107 markus 199: int ret = -1;
200:
1.194 markus 201: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 202: if (p != NULL &&
203: ask_permission("Allow use of key %s?\nKey fingerprint %s.",
1.122 djm 204: id->comment, p))
205: ret = 0;
1.173 djm 206: free(p);
1.122 djm 207:
1.107 markus 208: return (ret);
209: }
210:
1.194 markus 211: static void
212: send_status(SocketEntry *e, int success)
213: {
214: int r;
215:
216: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
217: (r = sshbuf_put_u8(e->output, success ?
218: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
219: fatal("%s: buffer error: %s", __func__, ssh_err(r));
220: }
221:
1.33 markus 222: /* send list of supported public keys to 'client' */
1.55 itojun 223: static void
1.33 markus 224: process_request_identities(SocketEntry *e, int version)
225: {
226: Idtab *tab = idtab_lookup(version);
1.96 deraadt 227: Identity *id;
1.194 markus 228: struct sshbuf *msg;
229: int r;
1.1 deraadt 230:
1.194 markus 231: if ((msg = sshbuf_new()) == NULL)
232: fatal("%s: sshbuf_new failed", __func__);
233: if ((r = sshbuf_put_u8(msg, (version == 1) ?
234: SSH_AGENT_RSA_IDENTITIES_ANSWER :
235: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
236: (r = sshbuf_put_u32(msg, tab->nentries)) != 0)
237: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.78 provos 238: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 239: if (id->key->type == KEY_RSA1) {
1.185 markus 240: #ifdef WITH_SSH1
1.194 markus 241: if ((r = sshbuf_put_u32(msg,
242: BN_num_bits(id->key->rsa->n))) != 0 ||
243: (r = sshbuf_put_bignum1(msg,
244: id->key->rsa->e)) != 0 ||
245: (r = sshbuf_put_bignum1(msg,
246: id->key->rsa->n)) != 0)
247: fatal("%s: buffer error: %s",
248: __func__, ssh_err(r));
1.185 markus 249: #endif
1.33 markus 250: } else {
1.45 markus 251: u_char *blob;
1.194 markus 252: size_t blen;
253:
254: if ((r = sshkey_to_blob(id->key, &blob, &blen)) != 0) {
255: error("%s: sshkey_to_blob: %s", __func__,
256: ssh_err(r));
257: continue;
258: }
259: if ((r = sshbuf_put_string(msg, blob, blen)) != 0)
260: fatal("%s: buffer error: %s",
261: __func__, ssh_err(r));
1.173 djm 262: free(blob);
1.33 markus 263: }
1.194 markus 264: if ((r = sshbuf_put_cstring(msg, id->comment)) != 0)
265: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 266: }
1.194 markus 267: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
268: fatal("%s: buffer error: %s", __func__, ssh_err(r));
269: sshbuf_free(msg);
1.1 deraadt 270: }
271:
1.185 markus 272: #ifdef WITH_SSH1
1.33 markus 273: /* ssh1 only */
1.55 itojun 274: static void
1.33 markus 275: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 276: {
1.96 deraadt 277: u_char buf[32], mdbuf[16], session_id[16];
278: u_int response_type;
279: BIGNUM *challenge;
1.78 provos 280: Identity *id;
1.194 markus 281: int r, len;
282: struct sshbuf *msg;
1.182 markus 283: struct ssh_digest_ctx *md;
1.194 markus 284: struct sshkey *key;
1.21 markus 285:
1.194 markus 286: if ((msg = sshbuf_new()) == NULL)
287: fatal("%s: sshbuf_new failed", __func__);
288: if ((key = sshkey_new(KEY_RSA1)) == NULL)
289: fatal("%s: sshkey_new failed", __func__);
1.76 markus 290: if ((challenge = BN_new()) == NULL)
1.194 markus 291: fatal("%s: BN_new failed", __func__);
1.33 markus 292:
1.194 markus 293: if ((r = sshbuf_get_u32(e->request, NULL)) != 0 || /* ignored */
294: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
295: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0 ||
296: (r = sshbuf_get_bignum1(e->request, challenge)))
297: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 298:
1.33 markus 299: /* Only protocol 1.1 is supported */
1.194 markus 300: if (sshbuf_len(e->request) == 0)
1.33 markus 301: goto failure;
1.194 markus 302: if ((r = sshbuf_get(e->request, session_id, sizeof(session_id))) != 0 ||
303: (r = sshbuf_get_u32(e->request, &response_type)) != 0)
304: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 305: if (response_type != 1)
306: goto failure;
307:
1.78 provos 308: id = lookup_identity(key, 1);
1.107 markus 309: if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
1.194 markus 310: struct sshkey *private = id->key;
1.33 markus 311: /* Decrypt the challenge using the private key. */
1.194 markus 312: if ((r = rsa_private_decrypt(challenge, challenge,
313: private->rsa) != 0)) {
314: fatal("%s: rsa_public_encrypt: %s", __func__,
315: ssh_err(r));
316: goto failure; /* XXX ? */
317: }
1.33 markus 318:
1.194 markus 319: /* The response is MD5 of decrypted challenge plus session id */
1.33 markus 320: len = BN_num_bytes(challenge);
321: if (len <= 0 || len > 32) {
1.194 markus 322: logit("%s: bad challenge length %d", __func__, len);
1.33 markus 323: goto failure;
324: }
325: memset(buf, 0, 32);
326: BN_bn2bin(challenge, buf + 32 - len);
1.182 markus 327: if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
328: ssh_digest_update(md, buf, 32) < 0 ||
329: ssh_digest_update(md, session_id, 16) < 0 ||
330: ssh_digest_final(md, mdbuf, sizeof(mdbuf)) < 0)
331: fatal("%s: md5 failed", __func__);
332: ssh_digest_free(md);
1.33 markus 333:
334: /* Send the response. */
1.194 markus 335: if ((r = sshbuf_put_u8(msg, SSH_AGENT_RSA_RESPONSE)) != 0 ||
336: (r = sshbuf_put(msg, mdbuf, sizeof(mdbuf))) != 0)
337: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 338: goto send;
339: }
1.21 markus 340:
1.194 markus 341: failure:
1.33 markus 342: /* Unknown identity or protocol error. Send failure. */
1.194 markus 343: if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
344: fatal("%s: buffer error: %s", __func__, ssh_err(r));
345: send:
346: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
347: fatal("%s: buffer error: %s", __func__, ssh_err(r));
348: sshkey_free(key);
1.33 markus 349: BN_clear_free(challenge);
1.194 markus 350: sshbuf_free(msg);
1.33 markus 351: }
1.185 markus 352: #endif
1.33 markus 353:
1.208 ! markus 354: static char *
! 355: agent_decode_alg(struct sshkey *key, u_int flags)
! 356: {
! 357: if (key->type == KEY_RSA) {
! 358: if (flags & SSH_AGENT_RSA_SHA2_256)
! 359: return "rsa-sha2-256";
! 360: else if (flags & SSH_AGENT_RSA_SHA2_512)
! 361: return "rsa-sha2-512";
! 362: }
! 363: return NULL;
! 364: }
! 365:
1.33 markus 366: /* ssh2 only */
1.55 itojun 367: static void
1.33 markus 368: process_sign_request2(SocketEntry *e)
369: {
1.45 markus 370: u_char *blob, *data, *signature = NULL;
1.194 markus 371: size_t blen, dlen, slen = 0;
372: u_int compat = 0, flags;
373: int r, ok = -1;
374: struct sshbuf *msg;
375: struct sshkey *key;
1.195 djm 376: struct identity *id;
1.194 markus 377:
1.195 djm 378: if ((msg = sshbuf_new()) == NULL)
379: fatal("%s: sshbuf_new failed", __func__);
1.194 markus 380: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0 ||
381: (r = sshbuf_get_string(e->request, &data, &dlen)) != 0 ||
382: (r = sshbuf_get_u32(e->request, &flags)) != 0)
383: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.37 markus 384: if (flags & SSH_AGENT_OLD_SIGNATURE)
1.194 markus 385: compat = SSH_BUG_SIGBLOB;
1.195 djm 386: if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
1.194 markus 387: error("%s: cannot parse key blob: %s", __func__, ssh_err(ok));
1.195 djm 388: goto send;
389: }
390: if ((id = lookup_identity(key, 2)) == NULL) {
391: verbose("%s: %s key not found", __func__, sshkey_type(key));
392: goto send;
393: }
394: if (id->confirm && confirm_key(id) != 0) {
395: verbose("%s: user refused key", __func__);
396: goto send;
397: }
398: if ((r = sshkey_sign(id->key, &signature, &slen,
1.208 ! markus 399: data, dlen, agent_decode_alg(key, flags), compat)) != 0) {
1.195 djm 400: error("%s: sshkey_sign: %s", __func__, ssh_err(ok));
401: goto send;
1.33 markus 402: }
1.195 djm 403: /* Success */
404: ok = 0;
405: send:
406: sshkey_free(key);
1.33 markus 407: if (ok == 0) {
1.194 markus 408: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
409: (r = sshbuf_put_string(msg, signature, slen)) != 0)
410: fatal("%s: buffer error: %s", __func__, ssh_err(r));
411: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
412: fatal("%s: buffer error: %s", __func__, ssh_err(r));
413:
414: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
415: fatal("%s: buffer error: %s", __func__, ssh_err(r));
416:
417: sshbuf_free(msg);
1.173 djm 418: free(data);
419: free(blob);
420: free(signature);
1.1 deraadt 421: }
422:
1.33 markus 423: /* shared */
1.55 itojun 424: static void
1.33 markus 425: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 426: {
1.194 markus 427: size_t blen;
428: int r, success = 0;
429: struct sshkey *key = NULL;
1.45 markus 430: u_char *blob;
1.186 djm 431: #ifdef WITH_SSH1
432: u_int bits;
433: #endif /* WITH_SSH1 */
1.21 markus 434:
1.74 deraadt 435: switch (version) {
1.186 djm 436: #ifdef WITH_SSH1
1.33 markus 437: case 1:
1.194 markus 438: if ((key = sshkey_new(KEY_RSA1)) == NULL) {
439: error("%s: sshkey_new failed", __func__);
440: return;
441: }
442: if ((r = sshbuf_get_u32(e->request, &bits)) != 0 ||
443: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
444: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0)
445: fatal("%s: buffer error: %s", __func__, ssh_err(r));
446:
447: if (bits != sshkey_size(key))
448: logit("Warning: identity keysize mismatch: "
449: "actual %u, announced %u",
450: sshkey_size(key), bits);
1.33 markus 451: break;
1.186 djm 452: #endif /* WITH_SSH1 */
1.33 markus 453: case 2:
1.194 markus 454: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0)
455: fatal("%s: buffer error: %s", __func__, ssh_err(r));
456: if ((r = sshkey_from_blob(blob, blen, &key)) != 0)
457: error("%s: sshkey_from_blob failed: %s",
458: __func__, ssh_err(r));
1.173 djm 459: free(blob);
1.33 markus 460: break;
461: }
462: if (key != NULL) {
1.78 provos 463: Identity *id = lookup_identity(key, version);
464: if (id != NULL) {
1.23 markus 465: /*
466: * We have this key. Free the old key. Since we
1.124 djm 467: * don't want to leave empty slots in the middle of
1.40 markus 468: * the array, we actually free the key there and move
469: * all the entries between the empty slot and the end
470: * of the array.
1.23 markus 471: */
1.33 markus 472: Idtab *tab = idtab_lookup(version);
1.38 markus 473: if (tab->nentries < 1)
474: fatal("process_remove_identity: "
475: "internal error: tab->nentries %d",
476: tab->nentries);
1.78 provos 477: TAILQ_REMOVE(&tab->idlist, id, next);
478: free_identity(id);
1.33 markus 479: tab->nentries--;
480: success = 1;
1.21 markus 481: }
1.194 markus 482: sshkey_free(key);
1.33 markus 483: }
1.194 markus 484: send_status(e, success);
1.1 deraadt 485: }
486:
1.55 itojun 487: static void
1.33 markus 488: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 489: {
1.33 markus 490: Idtab *tab = idtab_lookup(version);
1.78 provos 491: Identity *id;
1.21 markus 492:
493: /* Loop over all identities and clear the keys. */
1.78 provos 494: for (id = TAILQ_FIRST(&tab->idlist); id;
495: id = TAILQ_FIRST(&tab->idlist)) {
496: TAILQ_REMOVE(&tab->idlist, id, next);
497: free_identity(id);
1.21 markus 498: }
499:
500: /* Mark that there are no identities. */
1.33 markus 501: tab->nentries = 0;
1.21 markus 502:
503: /* Send success. */
1.194 markus 504: send_status(e, 1);
1.1 deraadt 505: }
506:
1.155 dtucker 507: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 508: static time_t
1.89 markus 509: reaper(void)
510: {
1.175 dtucker 511: time_t deadline = 0, now = monotime();
1.89 markus 512: Identity *id, *nxt;
513: int version;
1.96 deraadt 514: Idtab *tab;
1.89 markus 515:
516: for (version = 1; version < 3; version++) {
517: tab = idtab_lookup(version);
518: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
519: nxt = TAILQ_NEXT(id, next);
1.155 dtucker 520: if (id->death == 0)
521: continue;
522: if (now >= id->death) {
1.154 dtucker 523: debug("expiring key '%s'", id->comment);
1.89 markus 524: TAILQ_REMOVE(&tab->idlist, id, next);
525: free_identity(id);
526: tab->nentries--;
1.155 dtucker 527: } else
528: deadline = (deadline == 0) ? id->death :
529: MIN(deadline, id->death);
1.89 markus 530: }
531: }
1.155 dtucker 532: if (deadline == 0 || deadline <= now)
533: return 0;
534: else
535: return (deadline - now);
1.89 markus 536: }
537:
1.194 markus 538: /*
539: * XXX this and the corresponding serialisation function probably belongs
540: * in key.c
541: */
1.198 djm 542: #ifdef WITH_SSH1
1.194 markus 543: static int
544: agent_decode_rsa1(struct sshbuf *m, struct sshkey **kp)
545: {
546: struct sshkey *k = NULL;
547: int r = SSH_ERR_INTERNAL_ERROR;
548:
549: *kp = NULL;
550: if ((k = sshkey_new_private(KEY_RSA1)) == NULL)
551: return SSH_ERR_ALLOC_FAIL;
552:
553: if ((r = sshbuf_get_u32(m, NULL)) != 0 || /* ignored */
554: (r = sshbuf_get_bignum1(m, k->rsa->n)) != 0 ||
555: (r = sshbuf_get_bignum1(m, k->rsa->e)) != 0 ||
556: (r = sshbuf_get_bignum1(m, k->rsa->d)) != 0 ||
557: (r = sshbuf_get_bignum1(m, k->rsa->iqmp)) != 0 ||
558: /* SSH1 and SSL have p and q swapped */
559: (r = sshbuf_get_bignum1(m, k->rsa->q)) != 0 || /* p */
560: (r = sshbuf_get_bignum1(m, k->rsa->p)) != 0) /* q */
561: goto out;
562:
563: /* Generate additional parameters */
564: if ((r = rsa_generate_additional_parameters(k->rsa)) != 0)
565: goto out;
566: /* enable blinding */
567: if (RSA_blinding_on(k->rsa, NULL) != 1) {
568: r = SSH_ERR_LIBCRYPTO_ERROR;
569: goto out;
570: }
571:
572: r = 0; /* success */
573: out:
574: if (r == 0)
575: *kp = k;
576: else
577: sshkey_free(k);
578: return r;
579: }
1.198 djm 580: #endif /* WITH_SSH1 */
1.194 markus 581:
1.89 markus 582: static void
1.33 markus 583: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 584: {
1.96 deraadt 585: Idtab *tab = idtab_lookup(version);
1.157 canacar 586: Identity *id;
1.194 markus 587: int success = 0, confirm = 0;
588: u_int seconds;
589: char *comment = NULL;
1.174 dtucker 590: time_t death = 0;
1.194 markus 591: struct sshkey *k = NULL;
592: u_char ctype;
593: int r = SSH_ERR_INTERNAL_ERROR;
1.33 markus 594:
595: switch (version) {
1.186 djm 596: #ifdef WITH_SSH1
1.33 markus 597: case 1:
1.194 markus 598: r = agent_decode_rsa1(e->request, &k);
1.33 markus 599: break;
1.186 djm 600: #endif /* WITH_SSH1 */
1.33 markus 601: case 2:
1.194 markus 602: r = sshkey_private_deserialize(e->request, &k);
1.33 markus 603: break;
604: }
1.194 markus 605: if (r != 0 || k == NULL ||
606: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
607: error("%s: decode private key: %s", __func__, ssh_err(r));
608: goto err;
609: }
1.186 djm 610:
1.194 markus 611: while (sshbuf_len(e->request)) {
612: if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) {
613: error("%s: buffer error: %s", __func__, ssh_err(r));
614: goto err;
615: }
616: switch (ctype) {
1.94 markus 617: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 618: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) {
619: error("%s: bad lifetime constraint: %s",
620: __func__, ssh_err(r));
621: goto err;
622: }
623: death = monotime() + seconds;
1.94 markus 624: break;
1.107 markus 625: case SSH_AGENT_CONSTRAIN_CONFIRM:
626: confirm = 1;
627: break;
1.94 markus 628: default:
1.194 markus 629: error("%s: Unknown constraint %d", __func__, ctype);
630: err:
631: sshbuf_reset(e->request);
1.173 djm 632: free(comment);
1.194 markus 633: sshkey_free(k);
1.158 djm 634: goto send;
1.94 markus 635: }
636: }
1.194 markus 637:
1.158 djm 638: success = 1;
1.106 marc 639: if (lifetime && !death)
1.175 dtucker 640: death = monotime() + lifetime;
1.157 canacar 641: if ((id = lookup_identity(k, version)) == NULL) {
1.163 markus 642: id = xcalloc(1, sizeof(Identity));
1.78 provos 643: id->key = k;
644: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 645: /* Increment the number of identities. */
646: tab->nentries++;
647: } else {
1.194 markus 648: sshkey_free(k);
1.173 djm 649: free(id->comment);
1.33 markus 650: }
1.157 canacar 651: id->comment = comment;
652: id->death = death;
653: id->confirm = confirm;
1.33 markus 654: send:
1.194 markus 655: send_status(e, success);
1.1 deraadt 656: }
657:
1.88 markus 658: /* XXX todo: encrypt sensitive data with passphrase */
659: static void
660: process_lock_agent(SocketEntry *e, int lock)
661: {
1.203 dtucker 662: int r, success = 0, delay;
663: char *passwd, passwdhash[LOCK_SIZE];
664: static u_int fail_count = 0;
665: size_t pwlen;
666:
667: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
668: fatal("%s: buffer error: %s", __func__, ssh_err(r));
669: if (pwlen == 0) {
670: debug("empty password not supported");
671: } else if (locked && !lock) {
672: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
673: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
674: fatal("bcrypt_pbkdf");
675: if (timingsafe_bcmp(passwdhash, lock_passwd, LOCK_SIZE) == 0) {
676: debug("agent unlocked");
677: locked = 0;
678: fail_count = 0;
679: explicit_bzero(lock_passwd, sizeof(lock_passwd));
680: success = 1;
681: } else {
682: /* delay in 0.1s increments up to 10s */
683: if (fail_count < 100)
684: fail_count++;
685: delay = 100000 * fail_count;
686: debug("unlock failed, delaying %0.1lf seconds",
687: (double)delay/1000000);
688: usleep(delay);
689: }
690: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 691: } else if (!locked && lock) {
1.203 dtucker 692: debug("agent locked");
1.88 markus 693: locked = 1;
1.203 dtucker 694: arc4random_buf(lock_salt, sizeof(lock_salt));
695: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
696: lock_passwd, sizeof(lock_passwd), LOCK_ROUNDS) < 0)
697: fatal("bcrypt_pbkdf");
1.88 markus 698: success = 1;
699: }
1.203 dtucker 700: explicit_bzero(passwd, pwlen);
1.173 djm 701: free(passwd);
1.194 markus 702: send_status(e, success);
1.88 markus 703: }
704:
705: static void
706: no_identities(SocketEntry *e, u_int type)
707: {
1.194 markus 708: struct sshbuf *msg;
709: int r;
1.88 markus 710:
1.194 markus 711: if ((msg = sshbuf_new()) == NULL)
712: fatal("%s: sshbuf_new failed", __func__);
713: if ((r = sshbuf_put_u8(msg,
1.88 markus 714: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
1.194 markus 715: SSH_AGENT_RSA_IDENTITIES_ANSWER :
716: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
717: (r = sshbuf_put_u32(msg, 0)) != 0 ||
718: (r = sshbuf_put_stringb(e->output, msg)) != 0)
719: fatal("%s: buffer error: %s", __func__, ssh_err(r));
720: sshbuf_free(msg);
1.88 markus 721: }
1.59 markus 722:
1.163 markus 723: #ifdef ENABLE_PKCS11
1.59 markus 724: static void
1.158 djm 725: process_add_smartcard_key(SocketEntry *e)
1.59 markus 726: {
1.163 markus 727: char *provider = NULL, *pin;
1.194 markus 728: int r, i, version, count = 0, success = 0, confirm = 0;
729: u_int seconds;
1.174 dtucker 730: time_t death = 0;
1.194 markus 731: u_char type;
732: struct sshkey **keys = NULL, *k;
1.84 markus 733: Identity *id;
1.59 markus 734: Idtab *tab;
1.75 deraadt 735:
1.194 markus 736: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
737: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
738: fatal("%s: buffer error: %s", __func__, ssh_err(r));
739:
740: while (sshbuf_len(e->request)) {
741: if ((r = sshbuf_get_u8(e->request, &type)) != 0)
742: fatal("%s: buffer error: %s", __func__, ssh_err(r));
743: switch (type) {
1.110 djm 744: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 745: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
746: fatal("%s: buffer error: %s",
747: __func__, ssh_err(r));
748: death = monotime() + seconds;
1.110 djm 749: break;
750: case SSH_AGENT_CONSTRAIN_CONFIRM:
751: confirm = 1;
752: break;
753: default:
1.158 djm 754: error("process_add_smartcard_key: "
755: "Unknown constraint type %d", type);
756: goto send;
1.110 djm 757: }
758: }
759: if (lifetime && !death)
1.175 dtucker 760: death = monotime() + lifetime;
1.110 djm 761:
1.163 markus 762: count = pkcs11_add_provider(provider, pin, &keys);
763: for (i = 0; i < count; i++) {
1.84 markus 764: k = keys[i];
765: version = k->type == KEY_RSA1 ? 1 : 2;
766: tab = idtab_lookup(version);
767: if (lookup_identity(k, version) == NULL) {
1.163 markus 768: id = xcalloc(1, sizeof(Identity));
1.84 markus 769: id->key = k;
1.163 markus 770: id->provider = xstrdup(provider);
771: id->comment = xstrdup(provider); /* XXX */
1.110 djm 772: id->death = death;
773: id->confirm = confirm;
1.84 markus 774: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
775: tab->nentries++;
776: success = 1;
777: } else {
1.194 markus 778: sshkey_free(k);
1.84 markus 779: }
780: keys[i] = NULL;
1.59 markus 781: }
782: send:
1.173 djm 783: free(pin);
784: free(provider);
785: free(keys);
1.194 markus 786: send_status(e, success);
1.59 markus 787: }
788:
789: static void
790: process_remove_smartcard_key(SocketEntry *e)
791: {
1.163 markus 792: char *provider = NULL, *pin = NULL;
1.194 markus 793: int r, version, success = 0;
1.163 markus 794: Identity *id, *nxt;
1.84 markus 795: Idtab *tab;
1.59 markus 796:
1.194 markus 797: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
798: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
799: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.173 djm 800: free(pin);
1.59 markus 801:
1.163 markus 802: for (version = 1; version < 3; version++) {
803: tab = idtab_lookup(version);
804: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
805: nxt = TAILQ_NEXT(id, next);
1.181 djm 806: /* Skip file--based keys */
807: if (id->provider == NULL)
808: continue;
1.163 markus 809: if (!strcmp(provider, id->provider)) {
810: TAILQ_REMOVE(&tab->idlist, id, next);
811: free_identity(id);
812: tab->nentries--;
813: }
1.59 markus 814: }
815: }
1.163 markus 816: if (pkcs11_del_provider(provider) == 0)
817: success = 1;
818: else
819: error("process_remove_smartcard_key:"
820: " pkcs11_del_provider failed");
1.173 djm 821: free(provider);
1.194 markus 822: send_status(e, success);
1.59 markus 823: }
1.163 markus 824: #endif /* ENABLE_PKCS11 */
1.59 markus 825:
1.33 markus 826: /* dispatch incoming messages */
827:
1.55 itojun 828: static void
1.2 provos 829: process_message(SocketEntry *e)
1.1 deraadt 830: {
1.194 markus 831: u_int msg_len;
832: u_char type;
833: const u_char *cp;
834: int r;
1.89 markus 835:
1.194 markus 836: if (sshbuf_len(e->input) < 5)
1.21 markus 837: return; /* Incomplete message. */
1.194 markus 838: cp = sshbuf_ptr(e->input);
839: msg_len = PEEK_U32(cp);
1.21 markus 840: if (msg_len > 256 * 1024) {
1.101 stevesk 841: close_socket(e);
1.21 markus 842: return;
843: }
1.194 markus 844: if (sshbuf_len(e->input) < msg_len + 4)
1.21 markus 845: return;
1.87 markus 846:
847: /* move the current input to e->request */
1.194 markus 848: sshbuf_reset(e->request);
849: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
850: (r = sshbuf_get_u8(e->request, &type)) != 0)
851: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 852:
1.88 markus 853: /* check wheter agent is locked */
854: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 855: sshbuf_reset(e->request);
1.88 markus 856: switch (type) {
857: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
858: case SSH2_AGENTC_REQUEST_IDENTITIES:
859: /* send empty lists */
860: no_identities(e, type);
861: break;
862: default:
863: /* send a fail message for all other request types */
1.194 markus 864: send_status(e, 0);
1.88 markus 865: }
866: return;
867: }
868:
1.59 markus 869: debug("type %d", type);
1.21 markus 870: switch (type) {
1.88 markus 871: case SSH_AGENTC_LOCK:
872: case SSH_AGENTC_UNLOCK:
873: process_lock_agent(e, type == SSH_AGENTC_LOCK);
874: break;
1.185 markus 875: #ifdef WITH_SSH1
1.33 markus 876: /* ssh1 */
877: case SSH_AGENTC_RSA_CHALLENGE:
878: process_authentication_challenge1(e);
879: break;
1.21 markus 880: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 881: process_request_identities(e, 1);
1.21 markus 882: break;
883: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.94 markus 884: case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
1.33 markus 885: process_add_identity(e, 1);
1.21 markus 886: break;
887: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 888: process_remove_identity(e, 1);
1.21 markus 889: break;
1.199 djm 890: #endif
1.21 markus 891: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.199 djm 892: process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */
1.33 markus 893: break;
894: /* ssh2 */
895: case SSH2_AGENTC_SIGN_REQUEST:
896: process_sign_request2(e);
897: break;
898: case SSH2_AGENTC_REQUEST_IDENTITIES:
899: process_request_identities(e, 2);
900: break;
901: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 902: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.33 markus 903: process_add_identity(e, 2);
904: break;
905: case SSH2_AGENTC_REMOVE_IDENTITY:
906: process_remove_identity(e, 2);
907: break;
908: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
909: process_remove_all_identities(e, 2);
1.21 markus 910: break;
1.163 markus 911: #ifdef ENABLE_PKCS11
1.59 markus 912: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 913: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 914: process_add_smartcard_key(e);
1.75 deraadt 915: break;
1.59 markus 916: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
917: process_remove_smartcard_key(e);
1.75 deraadt 918: break;
1.163 markus 919: #endif /* ENABLE_PKCS11 */
1.21 markus 920: default:
921: /* Unknown message. Respond with failure. */
922: error("Unknown message %d", type);
1.194 markus 923: sshbuf_reset(e->request);
924: send_status(e, 0);
1.21 markus 925: break;
926: }
1.1 deraadt 927: }
928:
1.55 itojun 929: static void
1.73 stevesk 930: new_socket(sock_type type, int fd)
1.1 deraadt 931: {
1.112 markus 932: u_int i, old_alloc, new_alloc;
1.96 deraadt 933:
1.119 djm 934: set_nonblock(fd);
1.21 markus 935:
936: if (fd > max_fd)
937: max_fd = fd;
938:
939: for (i = 0; i < sockets_alloc; i++)
940: if (sockets[i].type == AUTH_UNUSED) {
941: sockets[i].fd = fd;
1.194 markus 942: if ((sockets[i].input = sshbuf_new()) == NULL)
943: fatal("%s: sshbuf_new failed", __func__);
944: if ((sockets[i].output = sshbuf_new()) == NULL)
945: fatal("%s: sshbuf_new failed", __func__);
946: if ((sockets[i].request = sshbuf_new()) == NULL)
947: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 948: sockets[i].type = type;
1.21 markus 949: return;
950: }
951: old_alloc = sockets_alloc;
1.112 markus 952: new_alloc = sockets_alloc + 10;
1.200 deraadt 953: sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 954: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 955: sockets[i].type = AUTH_UNUSED;
1.112 markus 956: sockets_alloc = new_alloc;
1.21 markus 957: sockets[old_alloc].fd = fd;
1.194 markus 958: if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
959: fatal("%s: sshbuf_new failed", __func__);
960: if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
961: fatal("%s: sshbuf_new failed", __func__);
962: if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
963: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 964: sockets[old_alloc].type = type;
1.1 deraadt 965: }
966:
1.55 itojun 967: static int
1.155 dtucker 968: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
969: struct timeval **tvpp)
1.1 deraadt 970: {
1.174 dtucker 971: u_int i, sz;
1.46 markus 972: int n = 0;
1.155 dtucker 973: static struct timeval tv;
1.174 dtucker 974: time_t deadline;
1.46 markus 975:
976: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 977: switch (sockets[i].type) {
978: case AUTH_SOCKET:
979: case AUTH_CONNECTION:
1.46 markus 980: n = MAX(n, sockets[i].fd);
1.21 markus 981: break;
982: case AUTH_UNUSED:
983: break;
984: default:
985: fatal("Unknown socket type %d", sockets[i].type);
986: break;
987: }
1.46 markus 988: }
989:
990: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 991: if (*fdrp == NULL || sz > *nallocp) {
1.173 djm 992: free(*fdrp);
993: free(*fdwp);
1.46 markus 994: *fdrp = xmalloc(sz);
995: *fdwp = xmalloc(sz);
1.66 markus 996: *nallocp = sz;
1.46 markus 997: }
1.66 markus 998: if (n < *fdl)
999: debug("XXX shrink: %d < %d", n, *fdl);
1000: *fdl = n;
1.46 markus 1001: memset(*fdrp, 0, sz);
1002: memset(*fdwp, 0, sz);
1003:
1004: for (i = 0; i < sockets_alloc; i++) {
1005: switch (sockets[i].type) {
1006: case AUTH_SOCKET:
1007: case AUTH_CONNECTION:
1008: FD_SET(sockets[i].fd, *fdrp);
1.194 markus 1009: if (sshbuf_len(sockets[i].output) > 0)
1.46 markus 1010: FD_SET(sockets[i].fd, *fdwp);
1011: break;
1012: default:
1013: break;
1014: }
1015: }
1.155 dtucker 1016: deadline = reaper();
1017: if (parent_alive_interval != 0)
1018: deadline = (deadline == 0) ? parent_alive_interval :
1019: MIN(deadline, parent_alive_interval);
1020: if (deadline == 0) {
1021: *tvpp = NULL;
1022: } else {
1023: tv.tv_sec = deadline;
1024: tv.tv_usec = 0;
1025: *tvpp = &tv;
1026: }
1.46 markus 1027: return (1);
1.21 markus 1028: }
1029:
1.55 itojun 1030: static void
1.21 markus 1031: after_select(fd_set *readset, fd_set *writeset)
1032: {
1.96 deraadt 1033: struct sockaddr_un sunaddr;
1.26 markus 1034: socklen_t slen;
1.21 markus 1035: char buf[1024];
1.194 markus 1036: int len, sock, r;
1.162 djm 1037: u_int i, orig_alloc;
1.103 markus 1038: uid_t euid;
1039: gid_t egid;
1.21 markus 1040:
1.162 djm 1041: for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
1.21 markus 1042: switch (sockets[i].type) {
1043: case AUTH_UNUSED:
1044: break;
1045: case AUTH_SOCKET:
1046: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 1047: slen = sizeof(sunaddr);
1.46 markus 1048: sock = accept(sockets[i].fd,
1.131 deraadt 1049: (struct sockaddr *)&sunaddr, &slen);
1.21 markus 1050: if (sock < 0) {
1.81 stevesk 1051: error("accept from AUTH_SOCKET: %s",
1052: strerror(errno));
1.103 markus 1053: break;
1054: }
1055: if (getpeereid(sock, &euid, &egid) < 0) {
1056: error("getpeereid %d failed: %s",
1057: sock, strerror(errno));
1058: close(sock);
1059: break;
1060: }
1.105 markus 1061: if ((euid != 0) && (getuid() != euid)) {
1.103 markus 1062: error("uid mismatch: "
1.104 stevesk 1063: "peer euid %u != uid %u",
1064: (u_int) euid, (u_int) getuid());
1.103 markus 1065: close(sock);
1.21 markus 1066: break;
1067: }
1068: new_socket(AUTH_CONNECTION, sock);
1069: }
1070: break;
1071: case AUTH_CONNECTION:
1.194 markus 1072: if (sshbuf_len(sockets[i].output) > 0 &&
1.21 markus 1073: FD_ISSET(sockets[i].fd, writeset)) {
1.162 djm 1074: len = write(sockets[i].fd,
1.194 markus 1075: sshbuf_ptr(sockets[i].output),
1076: sshbuf_len(sockets[i].output));
1.162 djm 1077: if (len == -1 && (errno == EAGAIN ||
1078: errno == EINTR))
1079: continue;
1.21 markus 1080: if (len <= 0) {
1.101 stevesk 1081: close_socket(&sockets[i]);
1.21 markus 1082: break;
1083: }
1.194 markus 1084: if ((r = sshbuf_consume(sockets[i].output,
1085: len)) != 0)
1086: fatal("%s: buffer error: %s",
1087: __func__, ssh_err(r));
1.21 markus 1088: }
1089: if (FD_ISSET(sockets[i].fd, readset)) {
1.162 djm 1090: len = read(sockets[i].fd, buf, sizeof(buf));
1091: if (len == -1 && (errno == EAGAIN ||
1092: errno == EINTR))
1093: continue;
1.21 markus 1094: if (len <= 0) {
1.101 stevesk 1095: close_socket(&sockets[i]);
1.21 markus 1096: break;
1097: }
1.194 markus 1098: if ((r = sshbuf_put(sockets[i].input,
1099: buf, len)) != 0)
1100: fatal("%s: buffer error: %s",
1101: __func__, ssh_err(r));
1.190 dtucker 1102: explicit_bzero(buf, sizeof(buf));
1.21 markus 1103: process_message(&sockets[i]);
1104: }
1105: break;
1106: default:
1107: fatal("Unknown type %d", sockets[i].type);
1108: }
1.1 deraadt 1109: }
1110:
1.55 itojun 1111: static void
1.113 markus 1112: cleanup_socket(void)
1.15 markus 1113: {
1.187 djm 1114: if (cleanup_pid != 0 && getpid() != cleanup_pid)
1115: return;
1116: debug("%s: cleanup", __func__);
1.48 deraadt 1117: if (socket_name[0])
1118: unlink(socket_name);
1119: if (socket_dir[0])
1120: rmdir(socket_dir);
1.10 markus 1121: }
1122:
1.114 markus 1123: void
1.15 markus 1124: cleanup_exit(int i)
1125: {
1.113 markus 1126: cleanup_socket();
1127: _exit(i);
1.15 markus 1128: }
1129:
1.135 deraadt 1130: /*ARGSUSED*/
1.55 itojun 1131: static void
1.48 deraadt 1132: cleanup_handler(int sig)
1133: {
1.113 markus 1134: cleanup_socket();
1.163 markus 1135: #ifdef ENABLE_PKCS11
1136: pkcs11_terminate();
1137: #endif
1.48 deraadt 1138: _exit(2);
1.113 markus 1139: }
1140:
1.68 markus 1141: static void
1.155 dtucker 1142: check_parent_exists(void)
1.68 markus 1143: {
1.172 dtucker 1144: /*
1145: * If our parent has exited then getppid() will return (pid_t)1,
1146: * so testing for that should be safe.
1147: */
1148: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 1149: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1150: cleanup_socket();
1151: _exit(2);
1.68 markus 1152: }
1.48 deraadt 1153: }
1154:
1.55 itojun 1155: static void
1.50 itojun 1156: usage(void)
1.15 markus 1157: {
1.184 deraadt 1158: fprintf(stderr,
1.202 jmc 1159: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.193 jmc 1160: " [-t life] [command [arg ...]]\n"
1.184 deraadt 1161: " ssh-agent [-c | -s] -k\n");
1.21 markus 1162: exit(1);
1.15 markus 1163: }
1164:
1.2 provos 1165: int
1166: main(int ac, char **av)
1.1 deraadt 1167: {
1.201 djm 1168: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1169: int sock, fd, ch, result, saved_errno;
1.120 avsm 1170: u_int nalloc;
1.96 deraadt 1171: char *shell, *format, *pidstr, *agentsocket = NULL;
1172: fd_set *readsetp = NULL, *writesetp = NULL;
1.41 markus 1173: struct rlimit rlim;
1.96 deraadt 1174: extern int optind;
1.98 stevesk 1175: extern char *optarg;
1.21 markus 1176: pid_t pid;
1.96 deraadt 1177: char pidstrbuf[1 + 3 * sizeof pid];
1.155 dtucker 1178: struct timeval *tvp = NULL;
1.161 tobias 1179: size_t len;
1.189 djm 1180: mode_t prev_mask;
1.123 djm 1181:
1182: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1183: sanitise_stdfd();
1.99 markus 1184:
1185: /* drop */
1186: setegid(getgid());
1187: setgid(getgid());
1.53 markus 1188:
1.185 markus 1189: #ifdef WITH_OPENSSL
1.170 djm 1190: OpenSSL_add_all_algorithms();
1.185 markus 1191: #endif
1.21 markus 1192:
1.201 djm 1193: while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) {
1.21 markus 1194: switch (ch) {
1.192 djm 1195: case 'E':
1196: fingerprint_hash = ssh_digest_alg_by_name(optarg);
1197: if (fingerprint_hash == -1)
1198: fatal("Invalid hash algorithm \"%s\"", optarg);
1199: break;
1.21 markus 1200: case 'c':
1201: if (s_flag)
1202: usage();
1203: c_flag++;
1204: break;
1205: case 'k':
1206: k_flag++;
1207: break;
1208: case 's':
1209: if (c_flag)
1210: usage();
1211: s_flag++;
1212: break;
1.57 markus 1213: case 'd':
1.201 djm 1214: if (d_flag || D_flag)
1.57 markus 1215: usage();
1216: d_flag++;
1217: break;
1.201 djm 1218: case 'D':
1219: if (d_flag || D_flag)
1220: usage();
1221: D_flag++;
1222: break;
1.86 markus 1223: case 'a':
1224: agentsocket = optarg;
1.106 marc 1225: break;
1226: case 't':
1227: if ((lifetime = convtime(optarg)) == -1) {
1228: fprintf(stderr, "Invalid lifetime\n");
1229: usage();
1230: }
1.86 markus 1231: break;
1.21 markus 1232: default:
1233: usage();
1234: }
1235: }
1236: ac -= optind;
1237: av += optind;
1238:
1.201 djm 1239: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 1240: usage();
1241:
1.85 markus 1242: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1243: shell = getenv("SHELL");
1.161 tobias 1244: if (shell != NULL && (len = strlen(shell)) > 2 &&
1245: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1246: c_flag = 1;
1247: }
1248: if (k_flag) {
1.136 deraadt 1249: const char *errstr = NULL;
1250:
1.21 markus 1251: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1252: if (pidstr == NULL) {
1253: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1254: SSH_AGENTPID_ENV_NAME);
1.21 markus 1255: exit(1);
1256: }
1.136 deraadt 1257: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1258: if (errstr) {
1259: fprintf(stderr,
1260: "%s=\"%s\", which is not a good PID: %s\n",
1261: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1262: exit(1);
1263: }
1264: if (kill(pid, SIGTERM) == -1) {
1265: perror("kill");
1266: exit(1);
1267: }
1268: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1269: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1270: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1271: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1272: exit(0);
1273: }
1274: parent_pid = getpid();
1275:
1.86 markus 1276: if (agentsocket == NULL) {
1277: /* Create private directory for agent socket */
1.171 djm 1278: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 1279: if (mkdtemp(socket_dir) == NULL) {
1280: perror("mkdtemp: private socket dir");
1281: exit(1);
1282: }
1.91 mpech 1283: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1284: (long)parent_pid);
1.86 markus 1285: } else {
1286: /* Try to use specified agent socket */
1287: socket_dir[0] = '\0';
1288: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1289: }
1290:
1.23 markus 1291: /*
1292: * Create socket early so it will exist before command gets run from
1293: * the parent.
1294: */
1.189 djm 1295: prev_mask = umask(0177);
1.188 millert 1296: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 1297: if (sock < 0) {
1.188 millert 1298: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 1299: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1300: cleanup_exit(1);
1301: }
1.189 djm 1302: umask(prev_mask);
1.46 markus 1303:
1.23 markus 1304: /*
1305: * Fork, and have the parent execute the command, if any, or present
1306: * the socket data. The child continues as the authentication agent.
1307: */
1.201 djm 1308: if (D_flag || d_flag) {
1309: log_init(__progname,
1310: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
1311: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 1312: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1313: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1314: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1315: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.57 markus 1316: goto skip;
1317: }
1.21 markus 1318: pid = fork();
1319: if (pid == -1) {
1320: perror("fork");
1.81 stevesk 1321: cleanup_exit(1);
1.21 markus 1322: }
1323: if (pid != 0) { /* Parent - execute the given command. */
1324: close(sock);
1.91 mpech 1325: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1326: if (ac == 0) {
1327: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1328: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1329: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1330: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1331: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1332: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1333: exit(0);
1334: }
1.36 deraadt 1335: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1336: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1337: perror("setenv");
1338: exit(1);
1339: }
1.21 markus 1340: execvp(av[0], av);
1341: perror(av[0]);
1342: exit(1);
1343: }
1.81 stevesk 1344: /* child */
1345: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1346:
1347: if (setsid() == -1) {
1.81 stevesk 1348: error("setsid: %s", strerror(errno));
1.67 stevesk 1349: cleanup_exit(1);
1350: }
1351:
1352: (void)chdir("/");
1.107 markus 1353: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1354: /* XXX might close listen socket */
1355: (void)dup2(fd, STDIN_FILENO);
1356: (void)dup2(fd, STDOUT_FILENO);
1357: (void)dup2(fd, STDERR_FILENO);
1358: if (fd > 2)
1359: close(fd);
1360: }
1.21 markus 1361:
1.41 markus 1362: /* deny core dumps, since memory contains unencrypted private keys */
1363: rlim.rlim_cur = rlim.rlim_max = 0;
1364: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1365: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1366: cleanup_exit(1);
1367: }
1.57 markus 1368:
1369: skip:
1.187 djm 1370:
1371: cleanup_pid = getpid();
1.163 markus 1372:
1373: #ifdef ENABLE_PKCS11
1374: pkcs11_init(0);
1375: #endif
1.21 markus 1376: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 1377: if (ac > 0)
1378: parent_alive_interval = 10;
1.33 markus 1379: idtab_init();
1.61 markus 1380: signal(SIGPIPE, SIG_IGN);
1.201 djm 1381: signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
1.48 deraadt 1382: signal(SIGHUP, cleanup_handler);
1383: signal(SIGTERM, cleanup_handler);
1.66 markus 1384: nalloc = 0;
1.205 djm 1385:
1.207 doug 1386: if (pledge("stdio cpath unix exec proc", NULL) != 0)
1.205 djm 1387: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 1388:
1.21 markus 1389: while (1) {
1.155 dtucker 1390: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
1391: result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
1.154 dtucker 1392: saved_errno = errno;
1.155 dtucker 1393: if (parent_alive_interval != 0)
1394: check_parent_exists();
1395: (void) reaper(); /* remove expired keys */
1.154 dtucker 1396: if (result < 0) {
1397: if (saved_errno == EINTR)
1.21 markus 1398: continue;
1.154 dtucker 1399: fatal("select: %s", strerror(saved_errno));
1400: } else if (result > 0)
1401: after_select(readsetp, writesetp);
1.15 markus 1402: }
1.21 markus 1403: /* NOTREACHED */
1.1 deraadt 1404: }
![[BACK]](/icons/back.gif){kind=icon}
Return to ssh-agent.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh