Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.215
1.215 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.214 2016/09/12 01:22:38 deraadt 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>
1.129 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>
1.196 deraadt 56: #include <limits.h>
1.145 stevesk 57: #include <time.h>
1.144 stevesk 58: #include <unistd.h>
1.203 dtucker 59: #include <util.h>
1.194 markus 60:
1.151 deraadt 61: #include "xmalloc.h"
1.1 deraadt 62: #include "ssh.h"
63: #include "rsa.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
! 79: # define DEFAULT_PKCS11_WHITELIST "/usr/lib/*,/usr/local/lib/*"
! 80: #endif
! 81:
1.73 stevesk 82: typedef enum {
83: AUTH_UNUSED,
84: AUTH_SOCKET,
85: AUTH_CONNECTION
86: } sock_type;
87:
1.21 markus 88: typedef struct {
89: int fd;
1.73 stevesk 90: sock_type type;
1.194 markus 91: struct sshbuf *input;
92: struct sshbuf *output;
93: struct sshbuf *request;
1.1 deraadt 94: } SocketEntry;
95:
1.45 markus 96: u_int sockets_alloc = 0;
1.1 deraadt 97: SocketEntry *sockets = NULL;
98:
1.78 provos 99: typedef struct identity {
100: TAILQ_ENTRY(identity) next;
1.194 markus 101: struct sshkey *key;
1.21 markus 102: char *comment;
1.163 markus 103: char *provider;
1.174 dtucker 104: time_t death;
1.107 markus 105: u_int confirm;
1.1 deraadt 106: } Identity;
107:
1.33 markus 108: typedef struct {
109: int nentries;
1.78 provos 110: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 111: } Idtab;
112:
113: /* private key table, one per protocol version */
114: Idtab idtable[3];
1.1 deraadt 115:
116: int max_fd = 0;
117:
1.11 markus 118: /* pid of shell == parent of agent */
1.29 deraadt 119: pid_t parent_pid = -1;
1.176 dtucker 120: time_t parent_alive_interval = 0;
1.10 markus 121:
1.187 djm 122: /* pid of process for which cleanup_socket is applicable */
123: pid_t cleanup_pid = 0;
124:
1.10 markus 125: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 126: char socket_name[PATH_MAX];
127: char socket_dir[PATH_MAX];
1.10 markus 128:
1.215 ! djm 129: /* PKCS#11 path whitelist */
! 130: static char *pkcs11_whitelist;
! 131:
1.88 markus 132: /* locking */
1.203 dtucker 133: #define LOCK_SIZE 32
134: #define LOCK_SALT_SIZE 16
135: #define LOCK_ROUNDS 1
1.88 markus 136: int locked = 0;
1.213 djm 137: u_char lock_pwhash[LOCK_SIZE];
138: u_char lock_salt[LOCK_SALT_SIZE];
1.88 markus 139:
1.20 markus 140: extern char *__progname;
141:
1.174 dtucker 142: /* Default lifetime in seconds (0 == forever) */
143: static long lifetime = 0;
1.106 marc 144:
1.192 djm 145: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
146:
1.55 itojun 147: static void
1.101 stevesk 148: close_socket(SocketEntry *e)
149: {
150: close(e->fd);
151: e->fd = -1;
152: e->type = AUTH_UNUSED;
1.194 markus 153: sshbuf_free(e->input);
154: sshbuf_free(e->output);
155: sshbuf_free(e->request);
1.101 stevesk 156: }
157:
158: static void
1.33 markus 159: idtab_init(void)
1.1 deraadt 160: {
1.33 markus 161: int i;
1.96 deraadt 162:
1.74 deraadt 163: for (i = 0; i <=2; i++) {
1.78 provos 164: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 165: idtable[i].nentries = 0;
166: }
167: }
168:
169: /* return private key table for requested protocol version */
1.55 itojun 170: static Idtab *
1.33 markus 171: idtab_lookup(int version)
172: {
173: if (version < 1 || version > 2)
174: fatal("internal error, bad protocol version %d", version);
175: return &idtable[version];
176: }
177:
1.89 markus 178: static void
179: free_identity(Identity *id)
180: {
1.194 markus 181: sshkey_free(id->key);
1.173 djm 182: free(id->provider);
183: free(id->comment);
184: free(id);
1.89 markus 185: }
186:
1.33 markus 187: /* return matching private key for given public key */
1.78 provos 188: static Identity *
1.194 markus 189: lookup_identity(struct sshkey *key, int version)
1.33 markus 190: {
1.78 provos 191: Identity *id;
192:
1.33 markus 193: Idtab *tab = idtab_lookup(version);
1.78 provos 194: TAILQ_FOREACH(id, &tab->idlist, next) {
1.194 markus 195: if (sshkey_equal(key, id->key))
1.78 provos 196: return (id);
1.33 markus 197: }
1.78 provos 198: return (NULL);
199: }
200:
1.107 markus 201: /* Check confirmation of keysign request */
202: static int
203: confirm_key(Identity *id)
204: {
1.122 djm 205: char *p;
1.107 markus 206: int ret = -1;
207:
1.194 markus 208: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 209: if (p != NULL &&
210: ask_permission("Allow use of key %s?\nKey fingerprint %s.",
1.122 djm 211: id->comment, p))
212: ret = 0;
1.173 djm 213: free(p);
1.122 djm 214:
1.107 markus 215: return (ret);
216: }
217:
1.194 markus 218: static void
219: send_status(SocketEntry *e, int success)
220: {
221: int r;
222:
223: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
224: (r = sshbuf_put_u8(e->output, success ?
225: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
226: fatal("%s: buffer error: %s", __func__, ssh_err(r));
227: }
228:
1.33 markus 229: /* send list of supported public keys to 'client' */
1.55 itojun 230: static void
1.33 markus 231: process_request_identities(SocketEntry *e, int version)
232: {
233: Idtab *tab = idtab_lookup(version);
1.96 deraadt 234: Identity *id;
1.194 markus 235: struct sshbuf *msg;
236: int r;
1.1 deraadt 237:
1.194 markus 238: if ((msg = sshbuf_new()) == NULL)
239: fatal("%s: sshbuf_new failed", __func__);
240: if ((r = sshbuf_put_u8(msg, (version == 1) ?
241: SSH_AGENT_RSA_IDENTITIES_ANSWER :
242: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
243: (r = sshbuf_put_u32(msg, tab->nentries)) != 0)
244: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.78 provos 245: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 246: if (id->key->type == KEY_RSA1) {
1.185 markus 247: #ifdef WITH_SSH1
1.194 markus 248: if ((r = sshbuf_put_u32(msg,
249: BN_num_bits(id->key->rsa->n))) != 0 ||
250: (r = sshbuf_put_bignum1(msg,
251: id->key->rsa->e)) != 0 ||
252: (r = sshbuf_put_bignum1(msg,
253: id->key->rsa->n)) != 0)
254: fatal("%s: buffer error: %s",
255: __func__, ssh_err(r));
1.185 markus 256: #endif
1.33 markus 257: } else {
1.45 markus 258: u_char *blob;
1.194 markus 259: size_t blen;
260:
261: if ((r = sshkey_to_blob(id->key, &blob, &blen)) != 0) {
262: error("%s: sshkey_to_blob: %s", __func__,
263: ssh_err(r));
264: continue;
265: }
266: if ((r = sshbuf_put_string(msg, blob, blen)) != 0)
267: fatal("%s: buffer error: %s",
268: __func__, ssh_err(r));
1.173 djm 269: free(blob);
1.33 markus 270: }
1.194 markus 271: if ((r = sshbuf_put_cstring(msg, id->comment)) != 0)
272: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 273: }
1.194 markus 274: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
275: fatal("%s: buffer error: %s", __func__, ssh_err(r));
276: sshbuf_free(msg);
1.1 deraadt 277: }
278:
1.185 markus 279: #ifdef WITH_SSH1
1.33 markus 280: /* ssh1 only */
1.55 itojun 281: static void
1.33 markus 282: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 283: {
1.96 deraadt 284: u_char buf[32], mdbuf[16], session_id[16];
285: u_int response_type;
286: BIGNUM *challenge;
1.78 provos 287: Identity *id;
1.194 markus 288: int r, len;
289: struct sshbuf *msg;
1.182 markus 290: struct ssh_digest_ctx *md;
1.194 markus 291: struct sshkey *key;
1.21 markus 292:
1.194 markus 293: if ((msg = sshbuf_new()) == NULL)
294: fatal("%s: sshbuf_new failed", __func__);
295: if ((key = sshkey_new(KEY_RSA1)) == NULL)
296: fatal("%s: sshkey_new failed", __func__);
1.76 markus 297: if ((challenge = BN_new()) == NULL)
1.194 markus 298: fatal("%s: BN_new failed", __func__);
1.33 markus 299:
1.194 markus 300: if ((r = sshbuf_get_u32(e->request, NULL)) != 0 || /* ignored */
301: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
302: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0 ||
303: (r = sshbuf_get_bignum1(e->request, challenge)))
304: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 305:
1.33 markus 306: /* Only protocol 1.1 is supported */
1.194 markus 307: if (sshbuf_len(e->request) == 0)
1.33 markus 308: goto failure;
1.194 markus 309: if ((r = sshbuf_get(e->request, session_id, sizeof(session_id))) != 0 ||
310: (r = sshbuf_get_u32(e->request, &response_type)) != 0)
311: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 312: if (response_type != 1)
313: goto failure;
314:
1.78 provos 315: id = lookup_identity(key, 1);
1.107 markus 316: if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
1.194 markus 317: struct sshkey *private = id->key;
1.33 markus 318: /* Decrypt the challenge using the private key. */
1.194 markus 319: if ((r = rsa_private_decrypt(challenge, challenge,
320: private->rsa) != 0)) {
321: fatal("%s: rsa_public_encrypt: %s", __func__,
322: ssh_err(r));
323: goto failure; /* XXX ? */
324: }
1.33 markus 325:
1.194 markus 326: /* The response is MD5 of decrypted challenge plus session id */
1.33 markus 327: len = BN_num_bytes(challenge);
328: if (len <= 0 || len > 32) {
1.194 markus 329: logit("%s: bad challenge length %d", __func__, len);
1.33 markus 330: goto failure;
331: }
332: memset(buf, 0, 32);
333: BN_bn2bin(challenge, buf + 32 - len);
1.182 markus 334: if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
335: ssh_digest_update(md, buf, 32) < 0 ||
336: ssh_digest_update(md, session_id, 16) < 0 ||
337: ssh_digest_final(md, mdbuf, sizeof(mdbuf)) < 0)
338: fatal("%s: md5 failed", __func__);
339: ssh_digest_free(md);
1.33 markus 340:
341: /* Send the response. */
1.194 markus 342: if ((r = sshbuf_put_u8(msg, SSH_AGENT_RSA_RESPONSE)) != 0 ||
343: (r = sshbuf_put(msg, mdbuf, sizeof(mdbuf))) != 0)
344: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 345: goto send;
346: }
1.21 markus 347:
1.194 markus 348: failure:
1.33 markus 349: /* Unknown identity or protocol error. Send failure. */
1.194 markus 350: if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
351: fatal("%s: buffer error: %s", __func__, ssh_err(r));
352: send:
353: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
354: fatal("%s: buffer error: %s", __func__, ssh_err(r));
355: sshkey_free(key);
1.33 markus 356: BN_clear_free(challenge);
1.194 markus 357: sshbuf_free(msg);
1.33 markus 358: }
1.185 markus 359: #endif
1.33 markus 360:
1.208 markus 361: static char *
362: agent_decode_alg(struct sshkey *key, u_int flags)
363: {
364: if (key->type == KEY_RSA) {
365: if (flags & SSH_AGENT_RSA_SHA2_256)
366: return "rsa-sha2-256";
367: else if (flags & SSH_AGENT_RSA_SHA2_512)
368: return "rsa-sha2-512";
369: }
370: return NULL;
371: }
372:
1.33 markus 373: /* ssh2 only */
1.55 itojun 374: static void
1.33 markus 375: process_sign_request2(SocketEntry *e)
376: {
1.45 markus 377: u_char *blob, *data, *signature = NULL;
1.194 markus 378: size_t blen, dlen, slen = 0;
379: u_int compat = 0, flags;
380: int r, ok = -1;
381: struct sshbuf *msg;
382: struct sshkey *key;
1.195 djm 383: struct identity *id;
1.194 markus 384:
1.195 djm 385: if ((msg = sshbuf_new()) == NULL)
386: fatal("%s: sshbuf_new failed", __func__);
1.194 markus 387: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0 ||
388: (r = sshbuf_get_string(e->request, &data, &dlen)) != 0 ||
389: (r = sshbuf_get_u32(e->request, &flags)) != 0)
390: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.37 markus 391: if (flags & SSH_AGENT_OLD_SIGNATURE)
1.194 markus 392: compat = SSH_BUG_SIGBLOB;
1.195 djm 393: if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
1.209 djm 394: error("%s: cannot parse key blob: %s", __func__, ssh_err(r));
1.195 djm 395: goto send;
396: }
397: if ((id = lookup_identity(key, 2)) == NULL) {
398: verbose("%s: %s key not found", __func__, sshkey_type(key));
399: goto send;
400: }
401: if (id->confirm && confirm_key(id) != 0) {
402: verbose("%s: user refused key", __func__);
403: goto send;
404: }
405: if ((r = sshkey_sign(id->key, &signature, &slen,
1.208 markus 406: data, dlen, agent_decode_alg(key, flags), compat)) != 0) {
1.209 djm 407: error("%s: sshkey_sign: %s", __func__, ssh_err(r));
1.195 djm 408: goto send;
1.33 markus 409: }
1.195 djm 410: /* Success */
411: ok = 0;
412: send:
413: sshkey_free(key);
1.33 markus 414: if (ok == 0) {
1.194 markus 415: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
416: (r = sshbuf_put_string(msg, signature, slen)) != 0)
417: fatal("%s: buffer error: %s", __func__, ssh_err(r));
418: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
419: fatal("%s: buffer error: %s", __func__, ssh_err(r));
420:
421: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
422: fatal("%s: buffer error: %s", __func__, ssh_err(r));
423:
424: sshbuf_free(msg);
1.173 djm 425: free(data);
426: free(blob);
427: free(signature);
1.1 deraadt 428: }
429:
1.33 markus 430: /* shared */
1.55 itojun 431: static void
1.33 markus 432: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 433: {
1.194 markus 434: size_t blen;
435: int r, success = 0;
436: struct sshkey *key = NULL;
1.45 markus 437: u_char *blob;
1.186 djm 438: #ifdef WITH_SSH1
439: u_int bits;
440: #endif /* WITH_SSH1 */
1.21 markus 441:
1.74 deraadt 442: switch (version) {
1.186 djm 443: #ifdef WITH_SSH1
1.33 markus 444: case 1:
1.194 markus 445: if ((key = sshkey_new(KEY_RSA1)) == NULL) {
446: error("%s: sshkey_new failed", __func__);
447: return;
448: }
449: if ((r = sshbuf_get_u32(e->request, &bits)) != 0 ||
450: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
451: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0)
452: fatal("%s: buffer error: %s", __func__, ssh_err(r));
453:
454: if (bits != sshkey_size(key))
455: logit("Warning: identity keysize mismatch: "
456: "actual %u, announced %u",
457: sshkey_size(key), bits);
1.33 markus 458: break;
1.186 djm 459: #endif /* WITH_SSH1 */
1.33 markus 460: case 2:
1.194 markus 461: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0)
462: fatal("%s: buffer error: %s", __func__, ssh_err(r));
463: if ((r = sshkey_from_blob(blob, blen, &key)) != 0)
464: error("%s: sshkey_from_blob failed: %s",
465: __func__, ssh_err(r));
1.173 djm 466: free(blob);
1.33 markus 467: break;
468: }
469: if (key != NULL) {
1.78 provos 470: Identity *id = lookup_identity(key, version);
471: if (id != NULL) {
1.23 markus 472: /*
473: * We have this key. Free the old key. Since we
1.124 djm 474: * don't want to leave empty slots in the middle of
1.40 markus 475: * the array, we actually free the key there and move
476: * all the entries between the empty slot and the end
477: * of the array.
1.23 markus 478: */
1.33 markus 479: Idtab *tab = idtab_lookup(version);
1.38 markus 480: if (tab->nentries < 1)
481: fatal("process_remove_identity: "
482: "internal error: tab->nentries %d",
483: tab->nentries);
1.78 provos 484: TAILQ_REMOVE(&tab->idlist, id, next);
485: free_identity(id);
1.33 markus 486: tab->nentries--;
487: success = 1;
1.21 markus 488: }
1.194 markus 489: sshkey_free(key);
1.33 markus 490: }
1.194 markus 491: send_status(e, success);
1.1 deraadt 492: }
493:
1.55 itojun 494: static void
1.33 markus 495: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 496: {
1.33 markus 497: Idtab *tab = idtab_lookup(version);
1.78 provos 498: Identity *id;
1.21 markus 499:
500: /* Loop over all identities and clear the keys. */
1.78 provos 501: for (id = TAILQ_FIRST(&tab->idlist); id;
502: id = TAILQ_FIRST(&tab->idlist)) {
503: TAILQ_REMOVE(&tab->idlist, id, next);
504: free_identity(id);
1.21 markus 505: }
506:
507: /* Mark that there are no identities. */
1.33 markus 508: tab->nentries = 0;
1.21 markus 509:
510: /* Send success. */
1.194 markus 511: send_status(e, 1);
1.1 deraadt 512: }
513:
1.155 dtucker 514: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 515: static time_t
1.89 markus 516: reaper(void)
517: {
1.175 dtucker 518: time_t deadline = 0, now = monotime();
1.89 markus 519: Identity *id, *nxt;
520: int version;
1.96 deraadt 521: Idtab *tab;
1.89 markus 522:
523: for (version = 1; version < 3; version++) {
524: tab = idtab_lookup(version);
525: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
526: nxt = TAILQ_NEXT(id, next);
1.155 dtucker 527: if (id->death == 0)
528: continue;
529: if (now >= id->death) {
1.154 dtucker 530: debug("expiring key '%s'", id->comment);
1.89 markus 531: TAILQ_REMOVE(&tab->idlist, id, next);
532: free_identity(id);
533: tab->nentries--;
1.155 dtucker 534: } else
535: deadline = (deadline == 0) ? id->death :
1.214 deraadt 536: MINIMUM(deadline, id->death);
1.89 markus 537: }
538: }
1.155 dtucker 539: if (deadline == 0 || deadline <= now)
540: return 0;
541: else
542: return (deadline - now);
1.89 markus 543: }
544:
1.194 markus 545: /*
546: * XXX this and the corresponding serialisation function probably belongs
547: * in key.c
548: */
1.198 djm 549: #ifdef WITH_SSH1
1.194 markus 550: static int
551: agent_decode_rsa1(struct sshbuf *m, struct sshkey **kp)
552: {
553: struct sshkey *k = NULL;
554: int r = SSH_ERR_INTERNAL_ERROR;
555:
556: *kp = NULL;
557: if ((k = sshkey_new_private(KEY_RSA1)) == NULL)
558: return SSH_ERR_ALLOC_FAIL;
559:
560: if ((r = sshbuf_get_u32(m, NULL)) != 0 || /* ignored */
561: (r = sshbuf_get_bignum1(m, k->rsa->n)) != 0 ||
562: (r = sshbuf_get_bignum1(m, k->rsa->e)) != 0 ||
563: (r = sshbuf_get_bignum1(m, k->rsa->d)) != 0 ||
564: (r = sshbuf_get_bignum1(m, k->rsa->iqmp)) != 0 ||
565: /* SSH1 and SSL have p and q swapped */
566: (r = sshbuf_get_bignum1(m, k->rsa->q)) != 0 || /* p */
567: (r = sshbuf_get_bignum1(m, k->rsa->p)) != 0) /* q */
568: goto out;
569:
570: /* Generate additional parameters */
571: if ((r = rsa_generate_additional_parameters(k->rsa)) != 0)
572: goto out;
573: /* enable blinding */
574: if (RSA_blinding_on(k->rsa, NULL) != 1) {
575: r = SSH_ERR_LIBCRYPTO_ERROR;
576: goto out;
577: }
578:
579: r = 0; /* success */
580: out:
581: if (r == 0)
582: *kp = k;
583: else
584: sshkey_free(k);
585: return r;
586: }
1.198 djm 587: #endif /* WITH_SSH1 */
1.194 markus 588:
1.89 markus 589: static void
1.33 markus 590: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 591: {
1.96 deraadt 592: Idtab *tab = idtab_lookup(version);
1.157 canacar 593: Identity *id;
1.194 markus 594: int success = 0, confirm = 0;
595: u_int seconds;
596: char *comment = NULL;
1.174 dtucker 597: time_t death = 0;
1.194 markus 598: struct sshkey *k = NULL;
599: u_char ctype;
600: int r = SSH_ERR_INTERNAL_ERROR;
1.33 markus 601:
602: switch (version) {
1.186 djm 603: #ifdef WITH_SSH1
1.33 markus 604: case 1:
1.194 markus 605: r = agent_decode_rsa1(e->request, &k);
1.33 markus 606: break;
1.186 djm 607: #endif /* WITH_SSH1 */
1.33 markus 608: case 2:
1.194 markus 609: r = sshkey_private_deserialize(e->request, &k);
1.33 markus 610: break;
611: }
1.194 markus 612: if (r != 0 || k == NULL ||
613: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
614: error("%s: decode private key: %s", __func__, ssh_err(r));
615: goto err;
616: }
1.186 djm 617:
1.194 markus 618: while (sshbuf_len(e->request)) {
619: if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) {
620: error("%s: buffer error: %s", __func__, ssh_err(r));
621: goto err;
622: }
623: switch (ctype) {
1.94 markus 624: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 625: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) {
626: error("%s: bad lifetime constraint: %s",
627: __func__, ssh_err(r));
628: goto err;
629: }
630: death = monotime() + seconds;
1.94 markus 631: break;
1.107 markus 632: case SSH_AGENT_CONSTRAIN_CONFIRM:
633: confirm = 1;
634: break;
1.94 markus 635: default:
1.194 markus 636: error("%s: Unknown constraint %d", __func__, ctype);
637: err:
638: sshbuf_reset(e->request);
1.173 djm 639: free(comment);
1.194 markus 640: sshkey_free(k);
1.158 djm 641: goto send;
1.94 markus 642: }
643: }
1.194 markus 644:
1.158 djm 645: success = 1;
1.106 marc 646: if (lifetime && !death)
1.175 dtucker 647: death = monotime() + lifetime;
1.157 canacar 648: if ((id = lookup_identity(k, version)) == NULL) {
1.163 markus 649: id = xcalloc(1, sizeof(Identity));
1.78 provos 650: id->key = k;
651: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 652: /* Increment the number of identities. */
653: tab->nentries++;
654: } else {
1.194 markus 655: sshkey_free(k);
1.173 djm 656: free(id->comment);
1.33 markus 657: }
1.157 canacar 658: id->comment = comment;
659: id->death = death;
660: id->confirm = confirm;
1.33 markus 661: send:
1.194 markus 662: send_status(e, success);
1.1 deraadt 663: }
664:
1.88 markus 665: /* XXX todo: encrypt sensitive data with passphrase */
666: static void
667: process_lock_agent(SocketEntry *e, int lock)
668: {
1.203 dtucker 669: int r, success = 0, delay;
1.213 djm 670: char *passwd;
671: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 672: static u_int fail_count = 0;
673: size_t pwlen;
674:
675: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
676: fatal("%s: buffer error: %s", __func__, ssh_err(r));
677: if (pwlen == 0) {
678: debug("empty password not supported");
679: } else if (locked && !lock) {
680: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
681: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
682: fatal("bcrypt_pbkdf");
1.213 djm 683: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 684: debug("agent unlocked");
685: locked = 0;
686: fail_count = 0;
1.213 djm 687: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 688: success = 1;
689: } else {
690: /* delay in 0.1s increments up to 10s */
691: if (fail_count < 100)
692: fail_count++;
693: delay = 100000 * fail_count;
694: debug("unlock failed, delaying %0.1lf seconds",
695: (double)delay/1000000);
696: usleep(delay);
697: }
698: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 699: } else if (!locked && lock) {
1.203 dtucker 700: debug("agent locked");
1.88 markus 701: locked = 1;
1.203 dtucker 702: arc4random_buf(lock_salt, sizeof(lock_salt));
703: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 djm 704: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 705: fatal("bcrypt_pbkdf");
1.88 markus 706: success = 1;
707: }
1.203 dtucker 708: explicit_bzero(passwd, pwlen);
1.173 djm 709: free(passwd);
1.194 markus 710: send_status(e, success);
1.88 markus 711: }
712:
713: static void
714: no_identities(SocketEntry *e, u_int type)
715: {
1.194 markus 716: struct sshbuf *msg;
717: int r;
1.88 markus 718:
1.194 markus 719: if ((msg = sshbuf_new()) == NULL)
720: fatal("%s: sshbuf_new failed", __func__);
721: if ((r = sshbuf_put_u8(msg,
1.88 markus 722: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
1.194 markus 723: SSH_AGENT_RSA_IDENTITIES_ANSWER :
724: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
725: (r = sshbuf_put_u32(msg, 0)) != 0 ||
726: (r = sshbuf_put_stringb(e->output, msg)) != 0)
727: fatal("%s: buffer error: %s", __func__, ssh_err(r));
728: sshbuf_free(msg);
1.88 markus 729: }
1.59 markus 730:
1.163 markus 731: #ifdef ENABLE_PKCS11
1.59 markus 732: static void
1.158 djm 733: process_add_smartcard_key(SocketEntry *e)
1.59 markus 734: {
1.215 ! djm 735: char *provider = NULL, *pin, canonical_provider[PATH_MAX];
1.194 markus 736: int r, i, version, count = 0, success = 0, confirm = 0;
737: u_int seconds;
1.174 dtucker 738: time_t death = 0;
1.194 markus 739: u_char type;
740: struct sshkey **keys = NULL, *k;
1.84 markus 741: Identity *id;
1.59 markus 742: Idtab *tab;
1.75 deraadt 743:
1.194 markus 744: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
745: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
746: fatal("%s: buffer error: %s", __func__, ssh_err(r));
747:
748: while (sshbuf_len(e->request)) {
749: if ((r = sshbuf_get_u8(e->request, &type)) != 0)
750: fatal("%s: buffer error: %s", __func__, ssh_err(r));
751: switch (type) {
1.110 djm 752: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 753: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
754: fatal("%s: buffer error: %s",
755: __func__, ssh_err(r));
756: death = monotime() + seconds;
1.110 djm 757: break;
758: case SSH_AGENT_CONSTRAIN_CONFIRM:
759: confirm = 1;
760: break;
761: default:
1.158 djm 762: error("process_add_smartcard_key: "
763: "Unknown constraint type %d", type);
764: goto send;
1.110 djm 765: }
766: }
1.215 ! djm 767: if (realpath(provider, canonical_provider) == NULL) {
! 768: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
! 769: provider, strerror(errno));
! 770: goto send;
! 771: }
! 772: if (match_pattern_list(canonical_provider, pkcs11_whitelist, 0) != 1) {
! 773: verbose("refusing PKCS#11 add of \"%.100s\": "
! 774: "provider not whitelisted", canonical_provider);
! 775: goto send;
! 776: }
! 777: debug("%s: add %.100s", __func__, canonical_provider);
1.110 djm 778: if (lifetime && !death)
1.175 dtucker 779: death = monotime() + lifetime;
1.110 djm 780:
1.215 ! djm 781: count = pkcs11_add_provider(canonical_provider, pin, &keys);
1.163 markus 782: for (i = 0; i < count; i++) {
1.84 markus 783: k = keys[i];
784: version = k->type == KEY_RSA1 ? 1 : 2;
785: tab = idtab_lookup(version);
786: if (lookup_identity(k, version) == NULL) {
1.163 markus 787: id = xcalloc(1, sizeof(Identity));
1.84 markus 788: id->key = k;
1.215 ! djm 789: id->provider = xstrdup(canonical_provider);
! 790: id->comment = xstrdup(canonical_provider); /* XXX */
1.110 djm 791: id->death = death;
792: id->confirm = confirm;
1.84 markus 793: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
794: tab->nentries++;
795: success = 1;
796: } else {
1.194 markus 797: sshkey_free(k);
1.84 markus 798: }
799: keys[i] = NULL;
1.59 markus 800: }
801: send:
1.173 djm 802: free(pin);
803: free(provider);
804: free(keys);
1.194 markus 805: send_status(e, success);
1.59 markus 806: }
807:
808: static void
809: process_remove_smartcard_key(SocketEntry *e)
810: {
1.163 markus 811: char *provider = NULL, *pin = NULL;
1.194 markus 812: int r, version, success = 0;
1.163 markus 813: Identity *id, *nxt;
1.84 markus 814: Idtab *tab;
1.59 markus 815:
1.194 markus 816: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
817: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
818: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.173 djm 819: free(pin);
1.59 markus 820:
1.163 markus 821: for (version = 1; version < 3; version++) {
822: tab = idtab_lookup(version);
823: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
824: nxt = TAILQ_NEXT(id, next);
1.181 djm 825: /* Skip file--based keys */
826: if (id->provider == NULL)
827: continue;
1.163 markus 828: if (!strcmp(provider, id->provider)) {
829: TAILQ_REMOVE(&tab->idlist, id, next);
830: free_identity(id);
831: tab->nentries--;
832: }
1.59 markus 833: }
834: }
1.163 markus 835: if (pkcs11_del_provider(provider) == 0)
836: success = 1;
837: else
838: error("process_remove_smartcard_key:"
839: " pkcs11_del_provider failed");
1.173 djm 840: free(provider);
1.194 markus 841: send_status(e, success);
1.59 markus 842: }
1.163 markus 843: #endif /* ENABLE_PKCS11 */
1.59 markus 844:
1.33 markus 845: /* dispatch incoming messages */
846:
1.55 itojun 847: static void
1.2 provos 848: process_message(SocketEntry *e)
1.1 deraadt 849: {
1.194 markus 850: u_int msg_len;
851: u_char type;
852: const u_char *cp;
853: int r;
1.89 markus 854:
1.194 markus 855: if (sshbuf_len(e->input) < 5)
1.21 markus 856: return; /* Incomplete message. */
1.194 markus 857: cp = sshbuf_ptr(e->input);
858: msg_len = PEEK_U32(cp);
1.21 markus 859: if (msg_len > 256 * 1024) {
1.101 stevesk 860: close_socket(e);
1.21 markus 861: return;
862: }
1.194 markus 863: if (sshbuf_len(e->input) < msg_len + 4)
1.21 markus 864: return;
1.87 markus 865:
866: /* move the current input to e->request */
1.194 markus 867: sshbuf_reset(e->request);
868: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
869: (r = sshbuf_get_u8(e->request, &type)) != 0)
870: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 871:
1.88 markus 872: /* check wheter agent is locked */
873: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 874: sshbuf_reset(e->request);
1.88 markus 875: switch (type) {
876: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
877: case SSH2_AGENTC_REQUEST_IDENTITIES:
878: /* send empty lists */
879: no_identities(e, type);
880: break;
881: default:
882: /* send a fail message for all other request types */
1.194 markus 883: send_status(e, 0);
1.88 markus 884: }
885: return;
886: }
887:
1.59 markus 888: debug("type %d", type);
1.21 markus 889: switch (type) {
1.88 markus 890: case SSH_AGENTC_LOCK:
891: case SSH_AGENTC_UNLOCK:
892: process_lock_agent(e, type == SSH_AGENTC_LOCK);
893: break;
1.185 markus 894: #ifdef WITH_SSH1
1.33 markus 895: /* ssh1 */
896: case SSH_AGENTC_RSA_CHALLENGE:
897: process_authentication_challenge1(e);
898: break;
1.21 markus 899: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 900: process_request_identities(e, 1);
1.21 markus 901: break;
902: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.94 markus 903: case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
1.33 markus 904: process_add_identity(e, 1);
1.21 markus 905: break;
906: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 907: process_remove_identity(e, 1);
1.21 markus 908: break;
1.199 djm 909: #endif
1.21 markus 910: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.199 djm 911: process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */
1.33 markus 912: break;
913: /* ssh2 */
914: case SSH2_AGENTC_SIGN_REQUEST:
915: process_sign_request2(e);
916: break;
917: case SSH2_AGENTC_REQUEST_IDENTITIES:
918: process_request_identities(e, 2);
919: break;
920: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 921: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.33 markus 922: process_add_identity(e, 2);
923: break;
924: case SSH2_AGENTC_REMOVE_IDENTITY:
925: process_remove_identity(e, 2);
926: break;
927: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
928: process_remove_all_identities(e, 2);
1.21 markus 929: break;
1.163 markus 930: #ifdef ENABLE_PKCS11
1.59 markus 931: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 932: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 933: process_add_smartcard_key(e);
1.75 deraadt 934: break;
1.59 markus 935: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
936: process_remove_smartcard_key(e);
1.75 deraadt 937: break;
1.163 markus 938: #endif /* ENABLE_PKCS11 */
1.21 markus 939: default:
940: /* Unknown message. Respond with failure. */
941: error("Unknown message %d", type);
1.194 markus 942: sshbuf_reset(e->request);
943: send_status(e, 0);
1.21 markus 944: break;
945: }
1.1 deraadt 946: }
947:
1.55 itojun 948: static void
1.73 stevesk 949: new_socket(sock_type type, int fd)
1.1 deraadt 950: {
1.112 markus 951: u_int i, old_alloc, new_alloc;
1.96 deraadt 952:
1.119 djm 953: set_nonblock(fd);
1.21 markus 954:
955: if (fd > max_fd)
956: max_fd = fd;
957:
958: for (i = 0; i < sockets_alloc; i++)
959: if (sockets[i].type == AUTH_UNUSED) {
960: sockets[i].fd = fd;
1.194 markus 961: if ((sockets[i].input = sshbuf_new()) == NULL)
962: fatal("%s: sshbuf_new failed", __func__);
963: if ((sockets[i].output = sshbuf_new()) == NULL)
964: fatal("%s: sshbuf_new failed", __func__);
965: if ((sockets[i].request = sshbuf_new()) == NULL)
966: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 967: sockets[i].type = type;
1.21 markus 968: return;
969: }
970: old_alloc = sockets_alloc;
1.112 markus 971: new_alloc = sockets_alloc + 10;
1.200 deraadt 972: sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 973: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 974: sockets[i].type = AUTH_UNUSED;
1.112 markus 975: sockets_alloc = new_alloc;
1.21 markus 976: sockets[old_alloc].fd = fd;
1.194 markus 977: if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
978: fatal("%s: sshbuf_new failed", __func__);
979: if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
980: fatal("%s: sshbuf_new failed", __func__);
981: if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
982: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 983: sockets[old_alloc].type = type;
1.1 deraadt 984: }
985:
1.55 itojun 986: static int
1.155 dtucker 987: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
988: struct timeval **tvpp)
1.1 deraadt 989: {
1.174 dtucker 990: u_int i, sz;
1.46 markus 991: int n = 0;
1.155 dtucker 992: static struct timeval tv;
1.174 dtucker 993: time_t deadline;
1.46 markus 994:
995: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 996: switch (sockets[i].type) {
997: case AUTH_SOCKET:
998: case AUTH_CONNECTION:
1.214 deraadt 999: n = MAXIMUM(n, sockets[i].fd);
1.21 markus 1000: break;
1001: case AUTH_UNUSED:
1002: break;
1003: default:
1004: fatal("Unknown socket type %d", sockets[i].type);
1005: break;
1006: }
1.46 markus 1007: }
1008:
1009: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 1010: if (*fdrp == NULL || sz > *nallocp) {
1.173 djm 1011: free(*fdrp);
1012: free(*fdwp);
1.46 markus 1013: *fdrp = xmalloc(sz);
1014: *fdwp = xmalloc(sz);
1.66 markus 1015: *nallocp = sz;
1.46 markus 1016: }
1.66 markus 1017: if (n < *fdl)
1018: debug("XXX shrink: %d < %d", n, *fdl);
1019: *fdl = n;
1.46 markus 1020: memset(*fdrp, 0, sz);
1021: memset(*fdwp, 0, sz);
1022:
1023: for (i = 0; i < sockets_alloc; i++) {
1024: switch (sockets[i].type) {
1025: case AUTH_SOCKET:
1026: case AUTH_CONNECTION:
1027: FD_SET(sockets[i].fd, *fdrp);
1.194 markus 1028: if (sshbuf_len(sockets[i].output) > 0)
1.46 markus 1029: FD_SET(sockets[i].fd, *fdwp);
1030: break;
1031: default:
1032: break;
1033: }
1034: }
1.155 dtucker 1035: deadline = reaper();
1036: if (parent_alive_interval != 0)
1037: deadline = (deadline == 0) ? parent_alive_interval :
1.214 deraadt 1038: MINIMUM(deadline, parent_alive_interval);
1.155 dtucker 1039: if (deadline == 0) {
1040: *tvpp = NULL;
1041: } else {
1042: tv.tv_sec = deadline;
1043: tv.tv_usec = 0;
1044: *tvpp = &tv;
1045: }
1.46 markus 1046: return (1);
1.21 markus 1047: }
1048:
1.55 itojun 1049: static void
1.21 markus 1050: after_select(fd_set *readset, fd_set *writeset)
1051: {
1.96 deraadt 1052: struct sockaddr_un sunaddr;
1.26 markus 1053: socklen_t slen;
1.21 markus 1054: char buf[1024];
1.194 markus 1055: int len, sock, r;
1.162 djm 1056: u_int i, orig_alloc;
1.103 markus 1057: uid_t euid;
1058: gid_t egid;
1.21 markus 1059:
1.162 djm 1060: for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
1.21 markus 1061: switch (sockets[i].type) {
1062: case AUTH_UNUSED:
1063: break;
1064: case AUTH_SOCKET:
1065: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 1066: slen = sizeof(sunaddr);
1.46 markus 1067: sock = accept(sockets[i].fd,
1.131 deraadt 1068: (struct sockaddr *)&sunaddr, &slen);
1.21 markus 1069: if (sock < 0) {
1.81 stevesk 1070: error("accept from AUTH_SOCKET: %s",
1071: strerror(errno));
1.103 markus 1072: break;
1073: }
1074: if (getpeereid(sock, &euid, &egid) < 0) {
1075: error("getpeereid %d failed: %s",
1076: sock, strerror(errno));
1077: close(sock);
1078: break;
1079: }
1.105 markus 1080: if ((euid != 0) && (getuid() != euid)) {
1.103 markus 1081: error("uid mismatch: "
1.104 stevesk 1082: "peer euid %u != uid %u",
1083: (u_int) euid, (u_int) getuid());
1.103 markus 1084: close(sock);
1.21 markus 1085: break;
1086: }
1087: new_socket(AUTH_CONNECTION, sock);
1088: }
1089: break;
1090: case AUTH_CONNECTION:
1.194 markus 1091: if (sshbuf_len(sockets[i].output) > 0 &&
1.21 markus 1092: FD_ISSET(sockets[i].fd, writeset)) {
1.162 djm 1093: len = write(sockets[i].fd,
1.194 markus 1094: sshbuf_ptr(sockets[i].output),
1095: sshbuf_len(sockets[i].output));
1.162 djm 1096: if (len == -1 && (errno == EAGAIN ||
1097: errno == EINTR))
1098: continue;
1.21 markus 1099: if (len <= 0) {
1.101 stevesk 1100: close_socket(&sockets[i]);
1.21 markus 1101: break;
1102: }
1.194 markus 1103: if ((r = sshbuf_consume(sockets[i].output,
1104: len)) != 0)
1105: fatal("%s: buffer error: %s",
1106: __func__, ssh_err(r));
1.21 markus 1107: }
1108: if (FD_ISSET(sockets[i].fd, readset)) {
1.162 djm 1109: len = read(sockets[i].fd, buf, sizeof(buf));
1110: if (len == -1 && (errno == EAGAIN ||
1111: errno == EINTR))
1112: continue;
1.21 markus 1113: if (len <= 0) {
1.101 stevesk 1114: close_socket(&sockets[i]);
1.21 markus 1115: break;
1116: }
1.194 markus 1117: if ((r = sshbuf_put(sockets[i].input,
1118: buf, len)) != 0)
1119: fatal("%s: buffer error: %s",
1120: __func__, ssh_err(r));
1.190 dtucker 1121: explicit_bzero(buf, sizeof(buf));
1.21 markus 1122: process_message(&sockets[i]);
1123: }
1124: break;
1125: default:
1126: fatal("Unknown type %d", sockets[i].type);
1127: }
1.1 deraadt 1128: }
1129:
1.55 itojun 1130: static void
1.113 markus 1131: cleanup_socket(void)
1.15 markus 1132: {
1.187 djm 1133: if (cleanup_pid != 0 && getpid() != cleanup_pid)
1134: return;
1135: debug("%s: cleanup", __func__);
1.48 deraadt 1136: if (socket_name[0])
1137: unlink(socket_name);
1138: if (socket_dir[0])
1139: rmdir(socket_dir);
1.10 markus 1140: }
1141:
1.114 markus 1142: void
1.15 markus 1143: cleanup_exit(int i)
1144: {
1.113 markus 1145: cleanup_socket();
1146: _exit(i);
1.15 markus 1147: }
1148:
1.135 deraadt 1149: /*ARGSUSED*/
1.55 itojun 1150: static void
1.48 deraadt 1151: cleanup_handler(int sig)
1152: {
1.113 markus 1153: cleanup_socket();
1.163 markus 1154: #ifdef ENABLE_PKCS11
1155: pkcs11_terminate();
1156: #endif
1.48 deraadt 1157: _exit(2);
1.113 markus 1158: }
1159:
1.68 markus 1160: static void
1.155 dtucker 1161: check_parent_exists(void)
1.68 markus 1162: {
1.172 dtucker 1163: /*
1164: * If our parent has exited then getppid() will return (pid_t)1,
1165: * so testing for that should be safe.
1166: */
1167: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 1168: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1169: cleanup_socket();
1170: _exit(2);
1.68 markus 1171: }
1.48 deraadt 1172: }
1173:
1.55 itojun 1174: static void
1.50 itojun 1175: usage(void)
1.15 markus 1176: {
1.184 deraadt 1177: fprintf(stderr,
1.202 jmc 1178: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.215 ! djm 1179: " [-P pkcs11_whitelist] [-t life] [command [arg ...]]\n"
1.184 deraadt 1180: " ssh-agent [-c | -s] -k\n");
1.21 markus 1181: exit(1);
1.15 markus 1182: }
1183:
1.2 provos 1184: int
1185: main(int ac, char **av)
1.1 deraadt 1186: {
1.201 djm 1187: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1188: int sock, fd, ch, result, saved_errno;
1.120 avsm 1189: u_int nalloc;
1.96 deraadt 1190: char *shell, *format, *pidstr, *agentsocket = NULL;
1191: fd_set *readsetp = NULL, *writesetp = NULL;
1.41 markus 1192: struct rlimit rlim;
1.96 deraadt 1193: extern int optind;
1.98 stevesk 1194: extern char *optarg;
1.21 markus 1195: pid_t pid;
1.96 deraadt 1196: char pidstrbuf[1 + 3 * sizeof pid];
1.155 dtucker 1197: struct timeval *tvp = NULL;
1.161 tobias 1198: size_t len;
1.189 djm 1199: mode_t prev_mask;
1.123 djm 1200:
1.212 dtucker 1201: ssh_malloc_init(); /* must be called before any mallocs */
1.123 djm 1202: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1203: sanitise_stdfd();
1.99 markus 1204:
1205: /* drop */
1206: setegid(getgid());
1207: setgid(getgid());
1.53 markus 1208:
1.185 markus 1209: #ifdef WITH_OPENSSL
1.170 djm 1210: OpenSSL_add_all_algorithms();
1.185 markus 1211: #endif
1.21 markus 1212:
1.215 ! djm 1213: while ((ch = getopt(ac, av, "cDdksE:a:P:t:")) != -1) {
1.21 markus 1214: switch (ch) {
1.192 djm 1215: case 'E':
1216: fingerprint_hash = ssh_digest_alg_by_name(optarg);
1217: if (fingerprint_hash == -1)
1218: fatal("Invalid hash algorithm \"%s\"", optarg);
1219: break;
1.21 markus 1220: case 'c':
1221: if (s_flag)
1222: usage();
1223: c_flag++;
1224: break;
1225: case 'k':
1226: k_flag++;
1227: break;
1.215 ! djm 1228: case 'P':
! 1229: if (pkcs11_whitelist != NULL)
! 1230: fatal("-P option already specified");
! 1231: pkcs11_whitelist = xstrdup(optarg);
! 1232: break;
1.21 markus 1233: case 's':
1234: if (c_flag)
1235: usage();
1236: s_flag++;
1237: break;
1.57 markus 1238: case 'd':
1.201 djm 1239: if (d_flag || D_flag)
1.57 markus 1240: usage();
1241: d_flag++;
1242: break;
1.201 djm 1243: case 'D':
1244: if (d_flag || D_flag)
1245: usage();
1246: D_flag++;
1247: break;
1.86 markus 1248: case 'a':
1249: agentsocket = optarg;
1.106 marc 1250: break;
1251: case 't':
1252: if ((lifetime = convtime(optarg)) == -1) {
1253: fprintf(stderr, "Invalid lifetime\n");
1254: usage();
1255: }
1.86 markus 1256: break;
1.21 markus 1257: default:
1258: usage();
1259: }
1260: }
1261: ac -= optind;
1262: av += optind;
1263:
1.201 djm 1264: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 1265: usage();
1266:
1.215 ! djm 1267: if (pkcs11_whitelist == NULL)
! 1268: pkcs11_whitelist = xstrdup(DEFAULT_PKCS11_WHITELIST);
! 1269:
1.85 markus 1270: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1271: shell = getenv("SHELL");
1.161 tobias 1272: if (shell != NULL && (len = strlen(shell)) > 2 &&
1273: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1274: c_flag = 1;
1275: }
1276: if (k_flag) {
1.136 deraadt 1277: const char *errstr = NULL;
1278:
1.21 markus 1279: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1280: if (pidstr == NULL) {
1281: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1282: SSH_AGENTPID_ENV_NAME);
1.21 markus 1283: exit(1);
1284: }
1.136 deraadt 1285: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1286: if (errstr) {
1287: fprintf(stderr,
1288: "%s=\"%s\", which is not a good PID: %s\n",
1289: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1290: exit(1);
1291: }
1292: if (kill(pid, SIGTERM) == -1) {
1293: perror("kill");
1294: exit(1);
1295: }
1296: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1297: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1298: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1299: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1300: exit(0);
1301: }
1302: parent_pid = getpid();
1303:
1.86 markus 1304: if (agentsocket == NULL) {
1305: /* Create private directory for agent socket */
1.171 djm 1306: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 1307: if (mkdtemp(socket_dir) == NULL) {
1308: perror("mkdtemp: private socket dir");
1309: exit(1);
1310: }
1.91 mpech 1311: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1312: (long)parent_pid);
1.86 markus 1313: } else {
1314: /* Try to use specified agent socket */
1315: socket_dir[0] = '\0';
1316: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1317: }
1318:
1.23 markus 1319: /*
1320: * Create socket early so it will exist before command gets run from
1321: * the parent.
1322: */
1.189 djm 1323: prev_mask = umask(0177);
1.188 millert 1324: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 1325: if (sock < 0) {
1.188 millert 1326: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 1327: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1328: cleanup_exit(1);
1329: }
1.189 djm 1330: umask(prev_mask);
1.46 markus 1331:
1.23 markus 1332: /*
1333: * Fork, and have the parent execute the command, if any, or present
1334: * the socket data. The child continues as the authentication agent.
1335: */
1.201 djm 1336: if (D_flag || d_flag) {
1337: log_init(__progname,
1338: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
1339: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 1340: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1341: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1342: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1343: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 1344: fflush(stdout);
1.57 markus 1345: goto skip;
1346: }
1.21 markus 1347: pid = fork();
1348: if (pid == -1) {
1349: perror("fork");
1.81 stevesk 1350: cleanup_exit(1);
1.21 markus 1351: }
1352: if (pid != 0) { /* Parent - execute the given command. */
1353: close(sock);
1.91 mpech 1354: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1355: if (ac == 0) {
1356: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1357: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1358: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1359: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1360: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1361: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1362: exit(0);
1363: }
1.36 deraadt 1364: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1365: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1366: perror("setenv");
1367: exit(1);
1368: }
1.21 markus 1369: execvp(av[0], av);
1370: perror(av[0]);
1371: exit(1);
1372: }
1.81 stevesk 1373: /* child */
1374: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1375:
1376: if (setsid() == -1) {
1.81 stevesk 1377: error("setsid: %s", strerror(errno));
1.67 stevesk 1378: cleanup_exit(1);
1379: }
1380:
1381: (void)chdir("/");
1.107 markus 1382: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1383: /* XXX might close listen socket */
1384: (void)dup2(fd, STDIN_FILENO);
1385: (void)dup2(fd, STDOUT_FILENO);
1386: (void)dup2(fd, STDERR_FILENO);
1387: if (fd > 2)
1388: close(fd);
1389: }
1.21 markus 1390:
1.41 markus 1391: /* deny core dumps, since memory contains unencrypted private keys */
1392: rlim.rlim_cur = rlim.rlim_max = 0;
1393: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1394: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1395: cleanup_exit(1);
1396: }
1.57 markus 1397:
1398: skip:
1.187 djm 1399:
1400: cleanup_pid = getpid();
1.163 markus 1401:
1402: #ifdef ENABLE_PKCS11
1403: pkcs11_init(0);
1404: #endif
1.21 markus 1405: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 1406: if (ac > 0)
1407: parent_alive_interval = 10;
1.33 markus 1408: idtab_init();
1.61 markus 1409: signal(SIGPIPE, SIG_IGN);
1.201 djm 1410: signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
1.48 deraadt 1411: signal(SIGHUP, cleanup_handler);
1412: signal(SIGTERM, cleanup_handler);
1.66 markus 1413: nalloc = 0;
1.205 djm 1414:
1.215 ! djm 1415: if (pledge("stdio rpath cpath unix id proc exec", NULL) == -1)
1.205 djm 1416: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 1417:
1.21 markus 1418: while (1) {
1.155 dtucker 1419: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
1420: result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
1.154 dtucker 1421: saved_errno = errno;
1.155 dtucker 1422: if (parent_alive_interval != 0)
1423: check_parent_exists();
1424: (void) reaper(); /* remove expired keys */
1.154 dtucker 1425: if (result < 0) {
1426: if (saved_errno == EINTR)
1.21 markus 1427: continue;
1.154 dtucker 1428: fatal("select: %s", strerror(saved_errno));
1429: } else if (result > 0)
1430: after_select(readsetp, writesetp);
1.15 markus 1431: }
1.21 markus 1432: /* NOTREACHED */
1.1 deraadt 1433: }
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