Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.213
1.213 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.212 2016/02/15 09:47:49 dtucker 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;
1.213 ! djm 130: u_char lock_pwhash[LOCK_SIZE];
! 131: u_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) {
1.209 djm 387: error("%s: cannot parse key blob: %s", __func__, ssh_err(r));
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) {
1.209 djm 400: error("%s: sshkey_sign: %s", __func__, ssh_err(r));
1.195 djm 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;
1.213 ! djm 663: char *passwd;
! 664: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 665: static u_int fail_count = 0;
666: size_t pwlen;
667:
668: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
669: fatal("%s: buffer error: %s", __func__, ssh_err(r));
670: if (pwlen == 0) {
671: debug("empty password not supported");
672: } else if (locked && !lock) {
673: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
674: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
675: fatal("bcrypt_pbkdf");
1.213 ! djm 676: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 677: debug("agent unlocked");
678: locked = 0;
679: fail_count = 0;
1.213 ! djm 680: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 681: success = 1;
682: } else {
683: /* delay in 0.1s increments up to 10s */
684: if (fail_count < 100)
685: fail_count++;
686: delay = 100000 * fail_count;
687: debug("unlock failed, delaying %0.1lf seconds",
688: (double)delay/1000000);
689: usleep(delay);
690: }
691: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 692: } else if (!locked && lock) {
1.203 dtucker 693: debug("agent locked");
1.88 markus 694: locked = 1;
1.203 dtucker 695: arc4random_buf(lock_salt, sizeof(lock_salt));
696: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 ! djm 697: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 698: fatal("bcrypt_pbkdf");
1.88 markus 699: success = 1;
700: }
1.203 dtucker 701: explicit_bzero(passwd, pwlen);
1.173 djm 702: free(passwd);
1.194 markus 703: send_status(e, success);
1.88 markus 704: }
705:
706: static void
707: no_identities(SocketEntry *e, u_int type)
708: {
1.194 markus 709: struct sshbuf *msg;
710: int r;
1.88 markus 711:
1.194 markus 712: if ((msg = sshbuf_new()) == NULL)
713: fatal("%s: sshbuf_new failed", __func__);
714: if ((r = sshbuf_put_u8(msg,
1.88 markus 715: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
1.194 markus 716: SSH_AGENT_RSA_IDENTITIES_ANSWER :
717: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
718: (r = sshbuf_put_u32(msg, 0)) != 0 ||
719: (r = sshbuf_put_stringb(e->output, msg)) != 0)
720: fatal("%s: buffer error: %s", __func__, ssh_err(r));
721: sshbuf_free(msg);
1.88 markus 722: }
1.59 markus 723:
1.163 markus 724: #ifdef ENABLE_PKCS11
1.59 markus 725: static void
1.158 djm 726: process_add_smartcard_key(SocketEntry *e)
1.59 markus 727: {
1.163 markus 728: char *provider = NULL, *pin;
1.194 markus 729: int r, i, version, count = 0, success = 0, confirm = 0;
730: u_int seconds;
1.174 dtucker 731: time_t death = 0;
1.194 markus 732: u_char type;
733: struct sshkey **keys = NULL, *k;
1.84 markus 734: Identity *id;
1.59 markus 735: Idtab *tab;
1.75 deraadt 736:
1.194 markus 737: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
738: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
739: fatal("%s: buffer error: %s", __func__, ssh_err(r));
740:
741: while (sshbuf_len(e->request)) {
742: if ((r = sshbuf_get_u8(e->request, &type)) != 0)
743: fatal("%s: buffer error: %s", __func__, ssh_err(r));
744: switch (type) {
1.110 djm 745: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 746: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
747: fatal("%s: buffer error: %s",
748: __func__, ssh_err(r));
749: death = monotime() + seconds;
1.110 djm 750: break;
751: case SSH_AGENT_CONSTRAIN_CONFIRM:
752: confirm = 1;
753: break;
754: default:
1.158 djm 755: error("process_add_smartcard_key: "
756: "Unknown constraint type %d", type);
757: goto send;
1.110 djm 758: }
759: }
760: if (lifetime && !death)
1.175 dtucker 761: death = monotime() + lifetime;
1.110 djm 762:
1.163 markus 763: count = pkcs11_add_provider(provider, pin, &keys);
764: for (i = 0; i < count; i++) {
1.84 markus 765: k = keys[i];
766: version = k->type == KEY_RSA1 ? 1 : 2;
767: tab = idtab_lookup(version);
768: if (lookup_identity(k, version) == NULL) {
1.163 markus 769: id = xcalloc(1, sizeof(Identity));
1.84 markus 770: id->key = k;
1.163 markus 771: id->provider = xstrdup(provider);
772: id->comment = xstrdup(provider); /* XXX */
1.110 djm 773: id->death = death;
774: id->confirm = confirm;
1.84 markus 775: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
776: tab->nentries++;
777: success = 1;
778: } else {
1.194 markus 779: sshkey_free(k);
1.84 markus 780: }
781: keys[i] = NULL;
1.59 markus 782: }
783: send:
1.173 djm 784: free(pin);
785: free(provider);
786: free(keys);
1.194 markus 787: send_status(e, success);
1.59 markus 788: }
789:
790: static void
791: process_remove_smartcard_key(SocketEntry *e)
792: {
1.163 markus 793: char *provider = NULL, *pin = NULL;
1.194 markus 794: int r, version, success = 0;
1.163 markus 795: Identity *id, *nxt;
1.84 markus 796: Idtab *tab;
1.59 markus 797:
1.194 markus 798: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
799: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
800: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.173 djm 801: free(pin);
1.59 markus 802:
1.163 markus 803: for (version = 1; version < 3; version++) {
804: tab = idtab_lookup(version);
805: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
806: nxt = TAILQ_NEXT(id, next);
1.181 djm 807: /* Skip file--based keys */
808: if (id->provider == NULL)
809: continue;
1.163 markus 810: if (!strcmp(provider, id->provider)) {
811: TAILQ_REMOVE(&tab->idlist, id, next);
812: free_identity(id);
813: tab->nentries--;
814: }
1.59 markus 815: }
816: }
1.163 markus 817: if (pkcs11_del_provider(provider) == 0)
818: success = 1;
819: else
820: error("process_remove_smartcard_key:"
821: " pkcs11_del_provider failed");
1.173 djm 822: free(provider);
1.194 markus 823: send_status(e, success);
1.59 markus 824: }
1.163 markus 825: #endif /* ENABLE_PKCS11 */
1.59 markus 826:
1.33 markus 827: /* dispatch incoming messages */
828:
1.55 itojun 829: static void
1.2 provos 830: process_message(SocketEntry *e)
1.1 deraadt 831: {
1.194 markus 832: u_int msg_len;
833: u_char type;
834: const u_char *cp;
835: int r;
1.89 markus 836:
1.194 markus 837: if (sshbuf_len(e->input) < 5)
1.21 markus 838: return; /* Incomplete message. */
1.194 markus 839: cp = sshbuf_ptr(e->input);
840: msg_len = PEEK_U32(cp);
1.21 markus 841: if (msg_len > 256 * 1024) {
1.101 stevesk 842: close_socket(e);
1.21 markus 843: return;
844: }
1.194 markus 845: if (sshbuf_len(e->input) < msg_len + 4)
1.21 markus 846: return;
1.87 markus 847:
848: /* move the current input to e->request */
1.194 markus 849: sshbuf_reset(e->request);
850: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
851: (r = sshbuf_get_u8(e->request, &type)) != 0)
852: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 853:
1.88 markus 854: /* check wheter agent is locked */
855: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 856: sshbuf_reset(e->request);
1.88 markus 857: switch (type) {
858: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
859: case SSH2_AGENTC_REQUEST_IDENTITIES:
860: /* send empty lists */
861: no_identities(e, type);
862: break;
863: default:
864: /* send a fail message for all other request types */
1.194 markus 865: send_status(e, 0);
1.88 markus 866: }
867: return;
868: }
869:
1.59 markus 870: debug("type %d", type);
1.21 markus 871: switch (type) {
1.88 markus 872: case SSH_AGENTC_LOCK:
873: case SSH_AGENTC_UNLOCK:
874: process_lock_agent(e, type == SSH_AGENTC_LOCK);
875: break;
1.185 markus 876: #ifdef WITH_SSH1
1.33 markus 877: /* ssh1 */
878: case SSH_AGENTC_RSA_CHALLENGE:
879: process_authentication_challenge1(e);
880: break;
1.21 markus 881: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 882: process_request_identities(e, 1);
1.21 markus 883: break;
884: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.94 markus 885: case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
1.33 markus 886: process_add_identity(e, 1);
1.21 markus 887: break;
888: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 889: process_remove_identity(e, 1);
1.21 markus 890: break;
1.199 djm 891: #endif
1.21 markus 892: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.199 djm 893: process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */
1.33 markus 894: break;
895: /* ssh2 */
896: case SSH2_AGENTC_SIGN_REQUEST:
897: process_sign_request2(e);
898: break;
899: case SSH2_AGENTC_REQUEST_IDENTITIES:
900: process_request_identities(e, 2);
901: break;
902: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 903: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.33 markus 904: process_add_identity(e, 2);
905: break;
906: case SSH2_AGENTC_REMOVE_IDENTITY:
907: process_remove_identity(e, 2);
908: break;
909: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
910: process_remove_all_identities(e, 2);
1.21 markus 911: break;
1.163 markus 912: #ifdef ENABLE_PKCS11
1.59 markus 913: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 914: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 915: process_add_smartcard_key(e);
1.75 deraadt 916: break;
1.59 markus 917: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
918: process_remove_smartcard_key(e);
1.75 deraadt 919: break;
1.163 markus 920: #endif /* ENABLE_PKCS11 */
1.21 markus 921: default:
922: /* Unknown message. Respond with failure. */
923: error("Unknown message %d", type);
1.194 markus 924: sshbuf_reset(e->request);
925: send_status(e, 0);
1.21 markus 926: break;
927: }
1.1 deraadt 928: }
929:
1.55 itojun 930: static void
1.73 stevesk 931: new_socket(sock_type type, int fd)
1.1 deraadt 932: {
1.112 markus 933: u_int i, old_alloc, new_alloc;
1.96 deraadt 934:
1.119 djm 935: set_nonblock(fd);
1.21 markus 936:
937: if (fd > max_fd)
938: max_fd = fd;
939:
940: for (i = 0; i < sockets_alloc; i++)
941: if (sockets[i].type == AUTH_UNUSED) {
942: sockets[i].fd = fd;
1.194 markus 943: if ((sockets[i].input = sshbuf_new()) == NULL)
944: fatal("%s: sshbuf_new failed", __func__);
945: if ((sockets[i].output = sshbuf_new()) == NULL)
946: fatal("%s: sshbuf_new failed", __func__);
947: if ((sockets[i].request = sshbuf_new()) == NULL)
948: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 949: sockets[i].type = type;
1.21 markus 950: return;
951: }
952: old_alloc = sockets_alloc;
1.112 markus 953: new_alloc = sockets_alloc + 10;
1.200 deraadt 954: sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 955: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 956: sockets[i].type = AUTH_UNUSED;
1.112 markus 957: sockets_alloc = new_alloc;
1.21 markus 958: sockets[old_alloc].fd = fd;
1.194 markus 959: if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
960: fatal("%s: sshbuf_new failed", __func__);
961: if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
962: fatal("%s: sshbuf_new failed", __func__);
963: if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
964: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 965: sockets[old_alloc].type = type;
1.1 deraadt 966: }
967:
1.55 itojun 968: static int
1.155 dtucker 969: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
970: struct timeval **tvpp)
1.1 deraadt 971: {
1.174 dtucker 972: u_int i, sz;
1.46 markus 973: int n = 0;
1.155 dtucker 974: static struct timeval tv;
1.174 dtucker 975: time_t deadline;
1.46 markus 976:
977: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 978: switch (sockets[i].type) {
979: case AUTH_SOCKET:
980: case AUTH_CONNECTION:
1.46 markus 981: n = MAX(n, sockets[i].fd);
1.21 markus 982: break;
983: case AUTH_UNUSED:
984: break;
985: default:
986: fatal("Unknown socket type %d", sockets[i].type);
987: break;
988: }
1.46 markus 989: }
990:
991: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 992: if (*fdrp == NULL || sz > *nallocp) {
1.173 djm 993: free(*fdrp);
994: free(*fdwp);
1.46 markus 995: *fdrp = xmalloc(sz);
996: *fdwp = xmalloc(sz);
1.66 markus 997: *nallocp = sz;
1.46 markus 998: }
1.66 markus 999: if (n < *fdl)
1000: debug("XXX shrink: %d < %d", n, *fdl);
1001: *fdl = n;
1.46 markus 1002: memset(*fdrp, 0, sz);
1003: memset(*fdwp, 0, sz);
1004:
1005: for (i = 0; i < sockets_alloc; i++) {
1006: switch (sockets[i].type) {
1007: case AUTH_SOCKET:
1008: case AUTH_CONNECTION:
1009: FD_SET(sockets[i].fd, *fdrp);
1.194 markus 1010: if (sshbuf_len(sockets[i].output) > 0)
1.46 markus 1011: FD_SET(sockets[i].fd, *fdwp);
1012: break;
1013: default:
1014: break;
1015: }
1016: }
1.155 dtucker 1017: deadline = reaper();
1018: if (parent_alive_interval != 0)
1019: deadline = (deadline == 0) ? parent_alive_interval :
1020: MIN(deadline, parent_alive_interval);
1021: if (deadline == 0) {
1022: *tvpp = NULL;
1023: } else {
1024: tv.tv_sec = deadline;
1025: tv.tv_usec = 0;
1026: *tvpp = &tv;
1027: }
1.46 markus 1028: return (1);
1.21 markus 1029: }
1030:
1.55 itojun 1031: static void
1.21 markus 1032: after_select(fd_set *readset, fd_set *writeset)
1033: {
1.96 deraadt 1034: struct sockaddr_un sunaddr;
1.26 markus 1035: socklen_t slen;
1.21 markus 1036: char buf[1024];
1.194 markus 1037: int len, sock, r;
1.162 djm 1038: u_int i, orig_alloc;
1.103 markus 1039: uid_t euid;
1040: gid_t egid;
1.21 markus 1041:
1.162 djm 1042: for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
1.21 markus 1043: switch (sockets[i].type) {
1044: case AUTH_UNUSED:
1045: break;
1046: case AUTH_SOCKET:
1047: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 1048: slen = sizeof(sunaddr);
1.46 markus 1049: sock = accept(sockets[i].fd,
1.131 deraadt 1050: (struct sockaddr *)&sunaddr, &slen);
1.21 markus 1051: if (sock < 0) {
1.81 stevesk 1052: error("accept from AUTH_SOCKET: %s",
1053: strerror(errno));
1.103 markus 1054: break;
1055: }
1056: if (getpeereid(sock, &euid, &egid) < 0) {
1057: error("getpeereid %d failed: %s",
1058: sock, strerror(errno));
1059: close(sock);
1060: break;
1061: }
1.105 markus 1062: if ((euid != 0) && (getuid() != euid)) {
1.103 markus 1063: error("uid mismatch: "
1.104 stevesk 1064: "peer euid %u != uid %u",
1065: (u_int) euid, (u_int) getuid());
1.103 markus 1066: close(sock);
1.21 markus 1067: break;
1068: }
1069: new_socket(AUTH_CONNECTION, sock);
1070: }
1071: break;
1072: case AUTH_CONNECTION:
1.194 markus 1073: if (sshbuf_len(sockets[i].output) > 0 &&
1.21 markus 1074: FD_ISSET(sockets[i].fd, writeset)) {
1.162 djm 1075: len = write(sockets[i].fd,
1.194 markus 1076: sshbuf_ptr(sockets[i].output),
1077: sshbuf_len(sockets[i].output));
1.162 djm 1078: if (len == -1 && (errno == EAGAIN ||
1079: errno == EINTR))
1080: continue;
1.21 markus 1081: if (len <= 0) {
1.101 stevesk 1082: close_socket(&sockets[i]);
1.21 markus 1083: break;
1084: }
1.194 markus 1085: if ((r = sshbuf_consume(sockets[i].output,
1086: len)) != 0)
1087: fatal("%s: buffer error: %s",
1088: __func__, ssh_err(r));
1.21 markus 1089: }
1090: if (FD_ISSET(sockets[i].fd, readset)) {
1.162 djm 1091: len = read(sockets[i].fd, buf, sizeof(buf));
1092: if (len == -1 && (errno == EAGAIN ||
1093: errno == EINTR))
1094: continue;
1.21 markus 1095: if (len <= 0) {
1.101 stevesk 1096: close_socket(&sockets[i]);
1.21 markus 1097: break;
1098: }
1.194 markus 1099: if ((r = sshbuf_put(sockets[i].input,
1100: buf, len)) != 0)
1101: fatal("%s: buffer error: %s",
1102: __func__, ssh_err(r));
1.190 dtucker 1103: explicit_bzero(buf, sizeof(buf));
1.21 markus 1104: process_message(&sockets[i]);
1105: }
1106: break;
1107: default:
1108: fatal("Unknown type %d", sockets[i].type);
1109: }
1.1 deraadt 1110: }
1111:
1.55 itojun 1112: static void
1.113 markus 1113: cleanup_socket(void)
1.15 markus 1114: {
1.187 djm 1115: if (cleanup_pid != 0 && getpid() != cleanup_pid)
1116: return;
1117: debug("%s: cleanup", __func__);
1.48 deraadt 1118: if (socket_name[0])
1119: unlink(socket_name);
1120: if (socket_dir[0])
1121: rmdir(socket_dir);
1.10 markus 1122: }
1123:
1.114 markus 1124: void
1.15 markus 1125: cleanup_exit(int i)
1126: {
1.113 markus 1127: cleanup_socket();
1128: _exit(i);
1.15 markus 1129: }
1130:
1.135 deraadt 1131: /*ARGSUSED*/
1.55 itojun 1132: static void
1.48 deraadt 1133: cleanup_handler(int sig)
1134: {
1.113 markus 1135: cleanup_socket();
1.163 markus 1136: #ifdef ENABLE_PKCS11
1137: pkcs11_terminate();
1138: #endif
1.48 deraadt 1139: _exit(2);
1.113 markus 1140: }
1141:
1.68 markus 1142: static void
1.155 dtucker 1143: check_parent_exists(void)
1.68 markus 1144: {
1.172 dtucker 1145: /*
1146: * If our parent has exited then getppid() will return (pid_t)1,
1147: * so testing for that should be safe.
1148: */
1149: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 1150: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1151: cleanup_socket();
1152: _exit(2);
1.68 markus 1153: }
1.48 deraadt 1154: }
1155:
1.55 itojun 1156: static void
1.50 itojun 1157: usage(void)
1.15 markus 1158: {
1.184 deraadt 1159: fprintf(stderr,
1.202 jmc 1160: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.193 jmc 1161: " [-t life] [command [arg ...]]\n"
1.184 deraadt 1162: " ssh-agent [-c | -s] -k\n");
1.21 markus 1163: exit(1);
1.15 markus 1164: }
1165:
1.2 provos 1166: int
1167: main(int ac, char **av)
1.1 deraadt 1168: {
1.201 djm 1169: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1170: int sock, fd, ch, result, saved_errno;
1.120 avsm 1171: u_int nalloc;
1.96 deraadt 1172: char *shell, *format, *pidstr, *agentsocket = NULL;
1173: fd_set *readsetp = NULL, *writesetp = NULL;
1.41 markus 1174: struct rlimit rlim;
1.96 deraadt 1175: extern int optind;
1.98 stevesk 1176: extern char *optarg;
1.21 markus 1177: pid_t pid;
1.96 deraadt 1178: char pidstrbuf[1 + 3 * sizeof pid];
1.155 dtucker 1179: struct timeval *tvp = NULL;
1.161 tobias 1180: size_t len;
1.189 djm 1181: mode_t prev_mask;
1.123 djm 1182:
1.212 dtucker 1183: ssh_malloc_init(); /* must be called before any mallocs */
1.123 djm 1184: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1185: sanitise_stdfd();
1.99 markus 1186:
1187: /* drop */
1188: setegid(getgid());
1189: setgid(getgid());
1.53 markus 1190:
1.185 markus 1191: #ifdef WITH_OPENSSL
1.170 djm 1192: OpenSSL_add_all_algorithms();
1.185 markus 1193: #endif
1.21 markus 1194:
1.201 djm 1195: while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) {
1.21 markus 1196: switch (ch) {
1.192 djm 1197: case 'E':
1198: fingerprint_hash = ssh_digest_alg_by_name(optarg);
1199: if (fingerprint_hash == -1)
1200: fatal("Invalid hash algorithm \"%s\"", optarg);
1201: break;
1.21 markus 1202: case 'c':
1203: if (s_flag)
1204: usage();
1205: c_flag++;
1206: break;
1207: case 'k':
1208: k_flag++;
1209: break;
1210: case 's':
1211: if (c_flag)
1212: usage();
1213: s_flag++;
1214: break;
1.57 markus 1215: case 'd':
1.201 djm 1216: if (d_flag || D_flag)
1.57 markus 1217: usage();
1218: d_flag++;
1219: break;
1.201 djm 1220: case 'D':
1221: if (d_flag || D_flag)
1222: usage();
1223: D_flag++;
1224: break;
1.86 markus 1225: case 'a':
1226: agentsocket = optarg;
1.106 marc 1227: break;
1228: case 't':
1229: if ((lifetime = convtime(optarg)) == -1) {
1230: fprintf(stderr, "Invalid lifetime\n");
1231: usage();
1232: }
1.86 markus 1233: break;
1.21 markus 1234: default:
1235: usage();
1236: }
1237: }
1238: ac -= optind;
1239: av += optind;
1240:
1.201 djm 1241: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 1242: usage();
1243:
1.85 markus 1244: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1245: shell = getenv("SHELL");
1.161 tobias 1246: if (shell != NULL && (len = strlen(shell)) > 2 &&
1247: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1248: c_flag = 1;
1249: }
1250: if (k_flag) {
1.136 deraadt 1251: const char *errstr = NULL;
1252:
1.21 markus 1253: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1254: if (pidstr == NULL) {
1255: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1256: SSH_AGENTPID_ENV_NAME);
1.21 markus 1257: exit(1);
1258: }
1.136 deraadt 1259: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1260: if (errstr) {
1261: fprintf(stderr,
1262: "%s=\"%s\", which is not a good PID: %s\n",
1263: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1264: exit(1);
1265: }
1266: if (kill(pid, SIGTERM) == -1) {
1267: perror("kill");
1268: exit(1);
1269: }
1270: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1271: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1272: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1273: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1274: exit(0);
1275: }
1276: parent_pid = getpid();
1277:
1.86 markus 1278: if (agentsocket == NULL) {
1279: /* Create private directory for agent socket */
1.171 djm 1280: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 1281: if (mkdtemp(socket_dir) == NULL) {
1282: perror("mkdtemp: private socket dir");
1283: exit(1);
1284: }
1.91 mpech 1285: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1286: (long)parent_pid);
1.86 markus 1287: } else {
1288: /* Try to use specified agent socket */
1289: socket_dir[0] = '\0';
1290: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1291: }
1292:
1.23 markus 1293: /*
1294: * Create socket early so it will exist before command gets run from
1295: * the parent.
1296: */
1.189 djm 1297: prev_mask = umask(0177);
1.188 millert 1298: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 1299: if (sock < 0) {
1.188 millert 1300: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 1301: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1302: cleanup_exit(1);
1303: }
1.189 djm 1304: umask(prev_mask);
1.46 markus 1305:
1.23 markus 1306: /*
1307: * Fork, and have the parent execute the command, if any, or present
1308: * the socket data. The child continues as the authentication agent.
1309: */
1.201 djm 1310: if (D_flag || d_flag) {
1311: log_init(__progname,
1312: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
1313: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 1314: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1315: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1316: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1317: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 1318: fflush(stdout);
1.57 markus 1319: goto skip;
1320: }
1.21 markus 1321: pid = fork();
1322: if (pid == -1) {
1323: perror("fork");
1.81 stevesk 1324: cleanup_exit(1);
1.21 markus 1325: }
1326: if (pid != 0) { /* Parent - execute the given command. */
1327: close(sock);
1.91 mpech 1328: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1329: if (ac == 0) {
1330: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1331: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1332: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1333: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1334: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1335: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1336: exit(0);
1337: }
1.36 deraadt 1338: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1339: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1340: perror("setenv");
1341: exit(1);
1342: }
1.21 markus 1343: execvp(av[0], av);
1344: perror(av[0]);
1345: exit(1);
1346: }
1.81 stevesk 1347: /* child */
1348: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1349:
1350: if (setsid() == -1) {
1.81 stevesk 1351: error("setsid: %s", strerror(errno));
1.67 stevesk 1352: cleanup_exit(1);
1353: }
1354:
1355: (void)chdir("/");
1.107 markus 1356: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1357: /* XXX might close listen socket */
1358: (void)dup2(fd, STDIN_FILENO);
1359: (void)dup2(fd, STDOUT_FILENO);
1360: (void)dup2(fd, STDERR_FILENO);
1361: if (fd > 2)
1362: close(fd);
1363: }
1.21 markus 1364:
1.41 markus 1365: /* deny core dumps, since memory contains unencrypted private keys */
1366: rlim.rlim_cur = rlim.rlim_max = 0;
1367: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1368: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1369: cleanup_exit(1);
1370: }
1.57 markus 1371:
1372: skip:
1.187 djm 1373:
1374: cleanup_pid = getpid();
1.163 markus 1375:
1376: #ifdef ENABLE_PKCS11
1377: pkcs11_init(0);
1378: #endif
1.21 markus 1379: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 1380: if (ac > 0)
1381: parent_alive_interval = 10;
1.33 markus 1382: idtab_init();
1.61 markus 1383: signal(SIGPIPE, SIG_IGN);
1.201 djm 1384: signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
1.48 deraadt 1385: signal(SIGHUP, cleanup_handler);
1386: signal(SIGTERM, cleanup_handler);
1.66 markus 1387: nalloc = 0;
1.205 djm 1388:
1.211 doug 1389: if (pledge("stdio cpath unix id proc exec", NULL) == -1)
1.205 djm 1390: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 1391:
1.21 markus 1392: while (1) {
1.155 dtucker 1393: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
1394: result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
1.154 dtucker 1395: saved_errno = errno;
1.155 dtucker 1396: if (parent_alive_interval != 0)
1397: check_parent_exists();
1398: (void) reaper(); /* remove expired keys */
1.154 dtucker 1399: if (result < 0) {
1400: if (saved_errno == EINTR)
1.21 markus 1401: continue;
1.154 dtucker 1402: fatal("select: %s", strerror(saved_errno));
1403: } else if (result > 0)
1404: after_select(readsetp, writesetp);
1.15 markus 1405: }
1.21 markus 1406: /* NOTREACHED */
1.1 deraadt 1407: }
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