Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.214
1.214 ! deraadt 1: /* $OpenBSD: ssh-agent.c,v 1.213 2016/05/02 08:49:03 djm Exp $ */
1.1 deraadt 2: /*
1.22 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * The authentication agent program.
1.33 markus 7: *
1.35 deraadt 8: * As far as I am concerned, the code I have written for this software
9: * can be used freely for any purpose. Any derived versions of this
10: * software must be clearly marked as such, and if the derived work is
11: * incompatible with the protocol description in the RFC file, it must be
12: * called by a name other than "ssh" or "Secure Shell".
13: *
1.56 markus 14: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.35 deraadt 15: *
16: * Redistribution and use in source and binary forms, with or without
17: * modification, are permitted provided that the following conditions
18: * are met:
19: * 1. Redistributions of source code must retain the above copyright
20: * notice, this list of conditions and the following disclaimer.
21: * 2. Redistributions in binary form must reproduce the above copyright
22: * notice, this list of conditions and the following disclaimer in the
23: * documentation and/or other materials provided with the distribution.
24: *
25: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.22 deraadt 35: */
1.1 deraadt 36:
1.151 deraadt 37: #include <sys/types.h>
1.153 djm 38: #include <sys/time.h>
1.78 provos 39: #include <sys/queue.h>
1.127 stevesk 40: #include <sys/resource.h>
1.141 stevesk 41: #include <sys/socket.h>
1.189 djm 42: #include <sys/stat.h>
1.128 stevesk 43: #include <sys/un.h>
1.126 stevesk 44:
1.185 markus 45: #ifdef WITH_OPENSSL
1.146 stevesk 46: #include <openssl/evp.h>
1.185 markus 47: #endif
1.146 stevesk 48:
1.143 stevesk 49: #include <errno.h>
1.142 stevesk 50: #include <fcntl.h>
1.126 stevesk 51: #include <paths.h>
1.129 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"
1.7 deraadt 72:
1.163 markus 73: #ifdef ENABLE_PKCS11
74: #include "ssh-pkcs11.h"
1.71 jakob 75: #endif
1.59 markus 76:
1.73 stevesk 77: typedef enum {
78: AUTH_UNUSED,
79: AUTH_SOCKET,
80: AUTH_CONNECTION
81: } sock_type;
82:
1.21 markus 83: typedef struct {
84: int fd;
1.73 stevesk 85: sock_type type;
1.194 markus 86: struct sshbuf *input;
87: struct sshbuf *output;
88: struct sshbuf *request;
1.1 deraadt 89: } SocketEntry;
90:
1.45 markus 91: u_int sockets_alloc = 0;
1.1 deraadt 92: SocketEntry *sockets = NULL;
93:
1.78 provos 94: typedef struct identity {
95: TAILQ_ENTRY(identity) next;
1.194 markus 96: struct sshkey *key;
1.21 markus 97: char *comment;
1.163 markus 98: char *provider;
1.174 dtucker 99: time_t death;
1.107 markus 100: u_int confirm;
1.1 deraadt 101: } Identity;
102:
1.33 markus 103: typedef struct {
104: int nentries;
1.78 provos 105: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 106: } Idtab;
107:
108: /* private key table, one per protocol version */
109: Idtab idtable[3];
1.1 deraadt 110:
111: int max_fd = 0;
112:
1.11 markus 113: /* pid of shell == parent of agent */
1.29 deraadt 114: pid_t parent_pid = -1;
1.176 dtucker 115: time_t parent_alive_interval = 0;
1.10 markus 116:
1.187 djm 117: /* pid of process for which cleanup_socket is applicable */
118: pid_t cleanup_pid = 0;
119:
1.10 markus 120: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 121: char socket_name[PATH_MAX];
122: char socket_dir[PATH_MAX];
1.10 markus 123:
1.88 markus 124: /* locking */
1.203 dtucker 125: #define LOCK_SIZE 32
126: #define LOCK_SALT_SIZE 16
127: #define LOCK_ROUNDS 1
1.88 markus 128: int locked = 0;
1.213 djm 129: u_char lock_pwhash[LOCK_SIZE];
130: u_char lock_salt[LOCK_SALT_SIZE];
1.88 markus 131:
1.20 markus 132: extern char *__progname;
133:
1.174 dtucker 134: /* Default lifetime in seconds (0 == forever) */
135: static long lifetime = 0;
1.106 marc 136:
1.192 djm 137: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
138:
1.55 itojun 139: static void
1.101 stevesk 140: close_socket(SocketEntry *e)
141: {
142: close(e->fd);
143: e->fd = -1;
144: e->type = AUTH_UNUSED;
1.194 markus 145: sshbuf_free(e->input);
146: sshbuf_free(e->output);
147: sshbuf_free(e->request);
1.101 stevesk 148: }
149:
150: static void
1.33 markus 151: idtab_init(void)
1.1 deraadt 152: {
1.33 markus 153: int i;
1.96 deraadt 154:
1.74 deraadt 155: for (i = 0; i <=2; i++) {
1.78 provos 156: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 157: idtable[i].nentries = 0;
158: }
159: }
160:
161: /* return private key table for requested protocol version */
1.55 itojun 162: static Idtab *
1.33 markus 163: idtab_lookup(int version)
164: {
165: if (version < 1 || version > 2)
166: fatal("internal error, bad protocol version %d", version);
167: return &idtable[version];
168: }
169:
1.89 markus 170: static void
171: free_identity(Identity *id)
172: {
1.194 markus 173: sshkey_free(id->key);
1.173 djm 174: free(id->provider);
175: free(id->comment);
176: free(id);
1.89 markus 177: }
178:
1.33 markus 179: /* return matching private key for given public key */
1.78 provos 180: static Identity *
1.194 markus 181: lookup_identity(struct sshkey *key, int version)
1.33 markus 182: {
1.78 provos 183: Identity *id;
184:
1.33 markus 185: Idtab *tab = idtab_lookup(version);
1.78 provos 186: TAILQ_FOREACH(id, &tab->idlist, next) {
1.194 markus 187: if (sshkey_equal(key, id->key))
1.78 provos 188: return (id);
1.33 markus 189: }
1.78 provos 190: return (NULL);
191: }
192:
1.107 markus 193: /* Check confirmation of keysign request */
194: static int
195: confirm_key(Identity *id)
196: {
1.122 djm 197: char *p;
1.107 markus 198: int ret = -1;
199:
1.194 markus 200: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 201: if (p != NULL &&
202: ask_permission("Allow use of key %s?\nKey fingerprint %s.",
1.122 djm 203: id->comment, p))
204: ret = 0;
1.173 djm 205: free(p);
1.122 djm 206:
1.107 markus 207: return (ret);
208: }
209:
1.194 markus 210: static void
211: send_status(SocketEntry *e, int success)
212: {
213: int r;
214:
215: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
216: (r = sshbuf_put_u8(e->output, success ?
217: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
218: fatal("%s: buffer error: %s", __func__, ssh_err(r));
219: }
220:
1.33 markus 221: /* send list of supported public keys to 'client' */
1.55 itojun 222: static void
1.33 markus 223: process_request_identities(SocketEntry *e, int version)
224: {
225: Idtab *tab = idtab_lookup(version);
1.96 deraadt 226: Identity *id;
1.194 markus 227: struct sshbuf *msg;
228: int r;
1.1 deraadt 229:
1.194 markus 230: if ((msg = sshbuf_new()) == NULL)
231: fatal("%s: sshbuf_new failed", __func__);
232: if ((r = sshbuf_put_u8(msg, (version == 1) ?
233: SSH_AGENT_RSA_IDENTITIES_ANSWER :
234: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
235: (r = sshbuf_put_u32(msg, tab->nentries)) != 0)
236: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.78 provos 237: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 238: if (id->key->type == KEY_RSA1) {
1.185 markus 239: #ifdef WITH_SSH1
1.194 markus 240: if ((r = sshbuf_put_u32(msg,
241: BN_num_bits(id->key->rsa->n))) != 0 ||
242: (r = sshbuf_put_bignum1(msg,
243: id->key->rsa->e)) != 0 ||
244: (r = sshbuf_put_bignum1(msg,
245: id->key->rsa->n)) != 0)
246: fatal("%s: buffer error: %s",
247: __func__, ssh_err(r));
1.185 markus 248: #endif
1.33 markus 249: } else {
1.45 markus 250: u_char *blob;
1.194 markus 251: size_t blen;
252:
253: if ((r = sshkey_to_blob(id->key, &blob, &blen)) != 0) {
254: error("%s: sshkey_to_blob: %s", __func__,
255: ssh_err(r));
256: continue;
257: }
258: if ((r = sshbuf_put_string(msg, blob, blen)) != 0)
259: fatal("%s: buffer error: %s",
260: __func__, ssh_err(r));
1.173 djm 261: free(blob);
1.33 markus 262: }
1.194 markus 263: if ((r = sshbuf_put_cstring(msg, id->comment)) != 0)
264: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 265: }
1.194 markus 266: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
267: fatal("%s: buffer error: %s", __func__, ssh_err(r));
268: sshbuf_free(msg);
1.1 deraadt 269: }
270:
1.185 markus 271: #ifdef WITH_SSH1
1.33 markus 272: /* ssh1 only */
1.55 itojun 273: static void
1.33 markus 274: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 275: {
1.96 deraadt 276: u_char buf[32], mdbuf[16], session_id[16];
277: u_int response_type;
278: BIGNUM *challenge;
1.78 provos 279: Identity *id;
1.194 markus 280: int r, len;
281: struct sshbuf *msg;
1.182 markus 282: struct ssh_digest_ctx *md;
1.194 markus 283: struct sshkey *key;
1.21 markus 284:
1.194 markus 285: if ((msg = sshbuf_new()) == NULL)
286: fatal("%s: sshbuf_new failed", __func__);
287: if ((key = sshkey_new(KEY_RSA1)) == NULL)
288: fatal("%s: sshkey_new failed", __func__);
1.76 markus 289: if ((challenge = BN_new()) == NULL)
1.194 markus 290: fatal("%s: BN_new failed", __func__);
1.33 markus 291:
1.194 markus 292: if ((r = sshbuf_get_u32(e->request, NULL)) != 0 || /* ignored */
293: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
294: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0 ||
295: (r = sshbuf_get_bignum1(e->request, challenge)))
296: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 297:
1.33 markus 298: /* Only protocol 1.1 is supported */
1.194 markus 299: if (sshbuf_len(e->request) == 0)
1.33 markus 300: goto failure;
1.194 markus 301: if ((r = sshbuf_get(e->request, session_id, sizeof(session_id))) != 0 ||
302: (r = sshbuf_get_u32(e->request, &response_type)) != 0)
303: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 304: if (response_type != 1)
305: goto failure;
306:
1.78 provos 307: id = lookup_identity(key, 1);
1.107 markus 308: if (id != NULL && (!id->confirm || confirm_key(id) == 0)) {
1.194 markus 309: struct sshkey *private = id->key;
1.33 markus 310: /* Decrypt the challenge using the private key. */
1.194 markus 311: if ((r = rsa_private_decrypt(challenge, challenge,
312: private->rsa) != 0)) {
313: fatal("%s: rsa_public_encrypt: %s", __func__,
314: ssh_err(r));
315: goto failure; /* XXX ? */
316: }
1.33 markus 317:
1.194 markus 318: /* The response is MD5 of decrypted challenge plus session id */
1.33 markus 319: len = BN_num_bytes(challenge);
320: if (len <= 0 || len > 32) {
1.194 markus 321: logit("%s: bad challenge length %d", __func__, len);
1.33 markus 322: goto failure;
323: }
324: memset(buf, 0, 32);
325: BN_bn2bin(challenge, buf + 32 - len);
1.182 markus 326: if ((md = ssh_digest_start(SSH_DIGEST_MD5)) == NULL ||
327: ssh_digest_update(md, buf, 32) < 0 ||
328: ssh_digest_update(md, session_id, 16) < 0 ||
329: ssh_digest_final(md, mdbuf, sizeof(mdbuf)) < 0)
330: fatal("%s: md5 failed", __func__);
331: ssh_digest_free(md);
1.33 markus 332:
333: /* Send the response. */
1.194 markus 334: if ((r = sshbuf_put_u8(msg, SSH_AGENT_RSA_RESPONSE)) != 0 ||
335: (r = sshbuf_put(msg, mdbuf, sizeof(mdbuf))) != 0)
336: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.33 markus 337: goto send;
338: }
1.21 markus 339:
1.194 markus 340: failure:
1.33 markus 341: /* Unknown identity or protocol error. Send failure. */
1.194 markus 342: if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
343: fatal("%s: buffer error: %s", __func__, ssh_err(r));
344: send:
345: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
346: fatal("%s: buffer error: %s", __func__, ssh_err(r));
347: sshkey_free(key);
1.33 markus 348: BN_clear_free(challenge);
1.194 markus 349: sshbuf_free(msg);
1.33 markus 350: }
1.185 markus 351: #endif
1.33 markus 352:
1.208 markus 353: static char *
354: agent_decode_alg(struct sshkey *key, u_int flags)
355: {
356: if (key->type == KEY_RSA) {
357: if (flags & SSH_AGENT_RSA_SHA2_256)
358: return "rsa-sha2-256";
359: else if (flags & SSH_AGENT_RSA_SHA2_512)
360: return "rsa-sha2-512";
361: }
362: return NULL;
363: }
364:
1.33 markus 365: /* ssh2 only */
1.55 itojun 366: static void
1.33 markus 367: process_sign_request2(SocketEntry *e)
368: {
1.45 markus 369: u_char *blob, *data, *signature = NULL;
1.194 markus 370: size_t blen, dlen, slen = 0;
371: u_int compat = 0, flags;
372: int r, ok = -1;
373: struct sshbuf *msg;
374: struct sshkey *key;
1.195 djm 375: struct identity *id;
1.194 markus 376:
1.195 djm 377: if ((msg = sshbuf_new()) == NULL)
378: fatal("%s: sshbuf_new failed", __func__);
1.194 markus 379: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0 ||
380: (r = sshbuf_get_string(e->request, &data, &dlen)) != 0 ||
381: (r = sshbuf_get_u32(e->request, &flags)) != 0)
382: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.37 markus 383: if (flags & SSH_AGENT_OLD_SIGNATURE)
1.194 markus 384: compat = SSH_BUG_SIGBLOB;
1.195 djm 385: if ((r = sshkey_from_blob(blob, blen, &key)) != 0) {
1.209 djm 386: error("%s: cannot parse key blob: %s", __func__, ssh_err(r));
1.195 djm 387: goto send;
388: }
389: if ((id = lookup_identity(key, 2)) == NULL) {
390: verbose("%s: %s key not found", __func__, sshkey_type(key));
391: goto send;
392: }
393: if (id->confirm && confirm_key(id) != 0) {
394: verbose("%s: user refused key", __func__);
395: goto send;
396: }
397: if ((r = sshkey_sign(id->key, &signature, &slen,
1.208 markus 398: data, dlen, agent_decode_alg(key, flags), compat)) != 0) {
1.209 djm 399: error("%s: sshkey_sign: %s", __func__, ssh_err(r));
1.195 djm 400: goto send;
1.33 markus 401: }
1.195 djm 402: /* Success */
403: ok = 0;
404: send:
405: sshkey_free(key);
1.33 markus 406: if (ok == 0) {
1.194 markus 407: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
408: (r = sshbuf_put_string(msg, signature, slen)) != 0)
409: fatal("%s: buffer error: %s", __func__, ssh_err(r));
410: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
411: fatal("%s: buffer error: %s", __func__, ssh_err(r));
412:
413: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
414: fatal("%s: buffer error: %s", __func__, ssh_err(r));
415:
416: sshbuf_free(msg);
1.173 djm 417: free(data);
418: free(blob);
419: free(signature);
1.1 deraadt 420: }
421:
1.33 markus 422: /* shared */
1.55 itojun 423: static void
1.33 markus 424: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 425: {
1.194 markus 426: size_t blen;
427: int r, success = 0;
428: struct sshkey *key = NULL;
1.45 markus 429: u_char *blob;
1.186 djm 430: #ifdef WITH_SSH1
431: u_int bits;
432: #endif /* WITH_SSH1 */
1.21 markus 433:
1.74 deraadt 434: switch (version) {
1.186 djm 435: #ifdef WITH_SSH1
1.33 markus 436: case 1:
1.194 markus 437: if ((key = sshkey_new(KEY_RSA1)) == NULL) {
438: error("%s: sshkey_new failed", __func__);
439: return;
440: }
441: if ((r = sshbuf_get_u32(e->request, &bits)) != 0 ||
442: (r = sshbuf_get_bignum1(e->request, key->rsa->e)) != 0 ||
443: (r = sshbuf_get_bignum1(e->request, key->rsa->n)) != 0)
444: fatal("%s: buffer error: %s", __func__, ssh_err(r));
445:
446: if (bits != sshkey_size(key))
447: logit("Warning: identity keysize mismatch: "
448: "actual %u, announced %u",
449: sshkey_size(key), bits);
1.33 markus 450: break;
1.186 djm 451: #endif /* WITH_SSH1 */
1.33 markus 452: case 2:
1.194 markus 453: if ((r = sshbuf_get_string(e->request, &blob, &blen)) != 0)
454: fatal("%s: buffer error: %s", __func__, ssh_err(r));
455: if ((r = sshkey_from_blob(blob, blen, &key)) != 0)
456: error("%s: sshkey_from_blob failed: %s",
457: __func__, ssh_err(r));
1.173 djm 458: free(blob);
1.33 markus 459: break;
460: }
461: if (key != NULL) {
1.78 provos 462: Identity *id = lookup_identity(key, version);
463: if (id != NULL) {
1.23 markus 464: /*
465: * We have this key. Free the old key. Since we
1.124 djm 466: * don't want to leave empty slots in the middle of
1.40 markus 467: * the array, we actually free the key there and move
468: * all the entries between the empty slot and the end
469: * of the array.
1.23 markus 470: */
1.33 markus 471: Idtab *tab = idtab_lookup(version);
1.38 markus 472: if (tab->nentries < 1)
473: fatal("process_remove_identity: "
474: "internal error: tab->nentries %d",
475: tab->nentries);
1.78 provos 476: TAILQ_REMOVE(&tab->idlist, id, next);
477: free_identity(id);
1.33 markus 478: tab->nentries--;
479: success = 1;
1.21 markus 480: }
1.194 markus 481: sshkey_free(key);
1.33 markus 482: }
1.194 markus 483: send_status(e, success);
1.1 deraadt 484: }
485:
1.55 itojun 486: static void
1.33 markus 487: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 488: {
1.33 markus 489: Idtab *tab = idtab_lookup(version);
1.78 provos 490: Identity *id;
1.21 markus 491:
492: /* Loop over all identities and clear the keys. */
1.78 provos 493: for (id = TAILQ_FIRST(&tab->idlist); id;
494: id = TAILQ_FIRST(&tab->idlist)) {
495: TAILQ_REMOVE(&tab->idlist, id, next);
496: free_identity(id);
1.21 markus 497: }
498:
499: /* Mark that there are no identities. */
1.33 markus 500: tab->nentries = 0;
1.21 markus 501:
502: /* Send success. */
1.194 markus 503: send_status(e, 1);
1.1 deraadt 504: }
505:
1.155 dtucker 506: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 507: static time_t
1.89 markus 508: reaper(void)
509: {
1.175 dtucker 510: time_t deadline = 0, now = monotime();
1.89 markus 511: Identity *id, *nxt;
512: int version;
1.96 deraadt 513: Idtab *tab;
1.89 markus 514:
515: for (version = 1; version < 3; version++) {
516: tab = idtab_lookup(version);
517: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
518: nxt = TAILQ_NEXT(id, next);
1.155 dtucker 519: if (id->death == 0)
520: continue;
521: if (now >= id->death) {
1.154 dtucker 522: debug("expiring key '%s'", id->comment);
1.89 markus 523: TAILQ_REMOVE(&tab->idlist, id, next);
524: free_identity(id);
525: tab->nentries--;
1.155 dtucker 526: } else
527: deadline = (deadline == 0) ? id->death :
1.214 ! deraadt 528: MINIMUM(deadline, id->death);
1.89 markus 529: }
530: }
1.155 dtucker 531: if (deadline == 0 || deadline <= now)
532: return 0;
533: else
534: return (deadline - now);
1.89 markus 535: }
536:
1.194 markus 537: /*
538: * XXX this and the corresponding serialisation function probably belongs
539: * in key.c
540: */
1.198 djm 541: #ifdef WITH_SSH1
1.194 markus 542: static int
543: agent_decode_rsa1(struct sshbuf *m, struct sshkey **kp)
544: {
545: struct sshkey *k = NULL;
546: int r = SSH_ERR_INTERNAL_ERROR;
547:
548: *kp = NULL;
549: if ((k = sshkey_new_private(KEY_RSA1)) == NULL)
550: return SSH_ERR_ALLOC_FAIL;
551:
552: if ((r = sshbuf_get_u32(m, NULL)) != 0 || /* ignored */
553: (r = sshbuf_get_bignum1(m, k->rsa->n)) != 0 ||
554: (r = sshbuf_get_bignum1(m, k->rsa->e)) != 0 ||
555: (r = sshbuf_get_bignum1(m, k->rsa->d)) != 0 ||
556: (r = sshbuf_get_bignum1(m, k->rsa->iqmp)) != 0 ||
557: /* SSH1 and SSL have p and q swapped */
558: (r = sshbuf_get_bignum1(m, k->rsa->q)) != 0 || /* p */
559: (r = sshbuf_get_bignum1(m, k->rsa->p)) != 0) /* q */
560: goto out;
561:
562: /* Generate additional parameters */
563: if ((r = rsa_generate_additional_parameters(k->rsa)) != 0)
564: goto out;
565: /* enable blinding */
566: if (RSA_blinding_on(k->rsa, NULL) != 1) {
567: r = SSH_ERR_LIBCRYPTO_ERROR;
568: goto out;
569: }
570:
571: r = 0; /* success */
572: out:
573: if (r == 0)
574: *kp = k;
575: else
576: sshkey_free(k);
577: return r;
578: }
1.198 djm 579: #endif /* WITH_SSH1 */
1.194 markus 580:
1.89 markus 581: static void
1.33 markus 582: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 583: {
1.96 deraadt 584: Idtab *tab = idtab_lookup(version);
1.157 canacar 585: Identity *id;
1.194 markus 586: int success = 0, confirm = 0;
587: u_int seconds;
588: char *comment = NULL;
1.174 dtucker 589: time_t death = 0;
1.194 markus 590: struct sshkey *k = NULL;
591: u_char ctype;
592: int r = SSH_ERR_INTERNAL_ERROR;
1.33 markus 593:
594: switch (version) {
1.186 djm 595: #ifdef WITH_SSH1
1.33 markus 596: case 1:
1.194 markus 597: r = agent_decode_rsa1(e->request, &k);
1.33 markus 598: break;
1.186 djm 599: #endif /* WITH_SSH1 */
1.33 markus 600: case 2:
1.194 markus 601: r = sshkey_private_deserialize(e->request, &k);
1.33 markus 602: break;
603: }
1.194 markus 604: if (r != 0 || k == NULL ||
605: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
606: error("%s: decode private key: %s", __func__, ssh_err(r));
607: goto err;
608: }
1.186 djm 609:
1.194 markus 610: while (sshbuf_len(e->request)) {
611: if ((r = sshbuf_get_u8(e->request, &ctype)) != 0) {
612: error("%s: buffer error: %s", __func__, ssh_err(r));
613: goto err;
614: }
615: switch (ctype) {
1.94 markus 616: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 617: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0) {
618: error("%s: bad lifetime constraint: %s",
619: __func__, ssh_err(r));
620: goto err;
621: }
622: death = monotime() + seconds;
1.94 markus 623: break;
1.107 markus 624: case SSH_AGENT_CONSTRAIN_CONFIRM:
625: confirm = 1;
626: break;
1.94 markus 627: default:
1.194 markus 628: error("%s: Unknown constraint %d", __func__, ctype);
629: err:
630: sshbuf_reset(e->request);
1.173 djm 631: free(comment);
1.194 markus 632: sshkey_free(k);
1.158 djm 633: goto send;
1.94 markus 634: }
635: }
1.194 markus 636:
1.158 djm 637: success = 1;
1.106 marc 638: if (lifetime && !death)
1.175 dtucker 639: death = monotime() + lifetime;
1.157 canacar 640: if ((id = lookup_identity(k, version)) == NULL) {
1.163 markus 641: id = xcalloc(1, sizeof(Identity));
1.78 provos 642: id->key = k;
643: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 644: /* Increment the number of identities. */
645: tab->nentries++;
646: } else {
1.194 markus 647: sshkey_free(k);
1.173 djm 648: free(id->comment);
1.33 markus 649: }
1.157 canacar 650: id->comment = comment;
651: id->death = death;
652: id->confirm = confirm;
1.33 markus 653: send:
1.194 markus 654: send_status(e, success);
1.1 deraadt 655: }
656:
1.88 markus 657: /* XXX todo: encrypt sensitive data with passphrase */
658: static void
659: process_lock_agent(SocketEntry *e, int lock)
660: {
1.203 dtucker 661: int r, success = 0, delay;
1.213 djm 662: char *passwd;
663: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 664: static u_int fail_count = 0;
665: size_t pwlen;
666:
667: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
668: fatal("%s: buffer error: %s", __func__, ssh_err(r));
669: if (pwlen == 0) {
670: debug("empty password not supported");
671: } else if (locked && !lock) {
672: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
673: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
674: fatal("bcrypt_pbkdf");
1.213 djm 675: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 676: debug("agent unlocked");
677: locked = 0;
678: fail_count = 0;
1.213 djm 679: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 680: success = 1;
681: } else {
682: /* delay in 0.1s increments up to 10s */
683: if (fail_count < 100)
684: fail_count++;
685: delay = 100000 * fail_count;
686: debug("unlock failed, delaying %0.1lf seconds",
687: (double)delay/1000000);
688: usleep(delay);
689: }
690: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 691: } else if (!locked && lock) {
1.203 dtucker 692: debug("agent locked");
1.88 markus 693: locked = 1;
1.203 dtucker 694: arc4random_buf(lock_salt, sizeof(lock_salt));
695: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 djm 696: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 697: fatal("bcrypt_pbkdf");
1.88 markus 698: success = 1;
699: }
1.203 dtucker 700: explicit_bzero(passwd, pwlen);
1.173 djm 701: free(passwd);
1.194 markus 702: send_status(e, success);
1.88 markus 703: }
704:
705: static void
706: no_identities(SocketEntry *e, u_int type)
707: {
1.194 markus 708: struct sshbuf *msg;
709: int r;
1.88 markus 710:
1.194 markus 711: if ((msg = sshbuf_new()) == NULL)
712: fatal("%s: sshbuf_new failed", __func__);
713: if ((r = sshbuf_put_u8(msg,
1.88 markus 714: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
1.194 markus 715: SSH_AGENT_RSA_IDENTITIES_ANSWER :
716: SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
717: (r = sshbuf_put_u32(msg, 0)) != 0 ||
718: (r = sshbuf_put_stringb(e->output, msg)) != 0)
719: fatal("%s: buffer error: %s", __func__, ssh_err(r));
720: sshbuf_free(msg);
1.88 markus 721: }
1.59 markus 722:
1.163 markus 723: #ifdef ENABLE_PKCS11
1.59 markus 724: static void
1.158 djm 725: process_add_smartcard_key(SocketEntry *e)
1.59 markus 726: {
1.163 markus 727: char *provider = NULL, *pin;
1.194 markus 728: int r, i, version, count = 0, success = 0, confirm = 0;
729: u_int seconds;
1.174 dtucker 730: time_t death = 0;
1.194 markus 731: u_char type;
732: struct sshkey **keys = NULL, *k;
1.84 markus 733: Identity *id;
1.59 markus 734: Idtab *tab;
1.75 deraadt 735:
1.194 markus 736: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
737: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
738: fatal("%s: buffer error: %s", __func__, ssh_err(r));
739:
740: while (sshbuf_len(e->request)) {
741: if ((r = sshbuf_get_u8(e->request, &type)) != 0)
742: fatal("%s: buffer error: %s", __func__, ssh_err(r));
743: switch (type) {
1.110 djm 744: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.194 markus 745: if ((r = sshbuf_get_u32(e->request, &seconds)) != 0)
746: fatal("%s: buffer error: %s",
747: __func__, ssh_err(r));
748: death = monotime() + seconds;
1.110 djm 749: break;
750: case SSH_AGENT_CONSTRAIN_CONFIRM:
751: confirm = 1;
752: break;
753: default:
1.158 djm 754: error("process_add_smartcard_key: "
755: "Unknown constraint type %d", type);
756: goto send;
1.110 djm 757: }
758: }
759: if (lifetime && !death)
1.175 dtucker 760: death = monotime() + lifetime;
1.110 djm 761:
1.163 markus 762: count = pkcs11_add_provider(provider, pin, &keys);
763: for (i = 0; i < count; i++) {
1.84 markus 764: k = keys[i];
765: version = k->type == KEY_RSA1 ? 1 : 2;
766: tab = idtab_lookup(version);
767: if (lookup_identity(k, version) == NULL) {
1.163 markus 768: id = xcalloc(1, sizeof(Identity));
1.84 markus 769: id->key = k;
1.163 markus 770: id->provider = xstrdup(provider);
771: id->comment = xstrdup(provider); /* XXX */
1.110 djm 772: id->death = death;
773: id->confirm = confirm;
1.84 markus 774: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
775: tab->nentries++;
776: success = 1;
777: } else {
1.194 markus 778: sshkey_free(k);
1.84 markus 779: }
780: keys[i] = NULL;
1.59 markus 781: }
782: send:
1.173 djm 783: free(pin);
784: free(provider);
785: free(keys);
1.194 markus 786: send_status(e, success);
1.59 markus 787: }
788:
789: static void
790: process_remove_smartcard_key(SocketEntry *e)
791: {
1.163 markus 792: char *provider = NULL, *pin = NULL;
1.194 markus 793: int r, version, success = 0;
1.163 markus 794: Identity *id, *nxt;
1.84 markus 795: Idtab *tab;
1.59 markus 796:
1.194 markus 797: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
798: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0)
799: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.173 djm 800: free(pin);
1.59 markus 801:
1.163 markus 802: for (version = 1; version < 3; version++) {
803: tab = idtab_lookup(version);
804: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
805: nxt = TAILQ_NEXT(id, next);
1.181 djm 806: /* Skip file--based keys */
807: if (id->provider == NULL)
808: continue;
1.163 markus 809: if (!strcmp(provider, id->provider)) {
810: TAILQ_REMOVE(&tab->idlist, id, next);
811: free_identity(id);
812: tab->nentries--;
813: }
1.59 markus 814: }
815: }
1.163 markus 816: if (pkcs11_del_provider(provider) == 0)
817: success = 1;
818: else
819: error("process_remove_smartcard_key:"
820: " pkcs11_del_provider failed");
1.173 djm 821: free(provider);
1.194 markus 822: send_status(e, success);
1.59 markus 823: }
1.163 markus 824: #endif /* ENABLE_PKCS11 */
1.59 markus 825:
1.33 markus 826: /* dispatch incoming messages */
827:
1.55 itojun 828: static void
1.2 provos 829: process_message(SocketEntry *e)
1.1 deraadt 830: {
1.194 markus 831: u_int msg_len;
832: u_char type;
833: const u_char *cp;
834: int r;
1.89 markus 835:
1.194 markus 836: if (sshbuf_len(e->input) < 5)
1.21 markus 837: return; /* Incomplete message. */
1.194 markus 838: cp = sshbuf_ptr(e->input);
839: msg_len = PEEK_U32(cp);
1.21 markus 840: if (msg_len > 256 * 1024) {
1.101 stevesk 841: close_socket(e);
1.21 markus 842: return;
843: }
1.194 markus 844: if (sshbuf_len(e->input) < msg_len + 4)
1.21 markus 845: return;
1.87 markus 846:
847: /* move the current input to e->request */
1.194 markus 848: sshbuf_reset(e->request);
849: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
850: (r = sshbuf_get_u8(e->request, &type)) != 0)
851: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.21 markus 852:
1.88 markus 853: /* check wheter agent is locked */
854: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 855: sshbuf_reset(e->request);
1.88 markus 856: switch (type) {
857: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
858: case SSH2_AGENTC_REQUEST_IDENTITIES:
859: /* send empty lists */
860: no_identities(e, type);
861: break;
862: default:
863: /* send a fail message for all other request types */
1.194 markus 864: send_status(e, 0);
1.88 markus 865: }
866: return;
867: }
868:
1.59 markus 869: debug("type %d", type);
1.21 markus 870: switch (type) {
1.88 markus 871: case SSH_AGENTC_LOCK:
872: case SSH_AGENTC_UNLOCK:
873: process_lock_agent(e, type == SSH_AGENTC_LOCK);
874: break;
1.185 markus 875: #ifdef WITH_SSH1
1.33 markus 876: /* ssh1 */
877: case SSH_AGENTC_RSA_CHALLENGE:
878: process_authentication_challenge1(e);
879: break;
1.21 markus 880: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 881: process_request_identities(e, 1);
1.21 markus 882: break;
883: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.94 markus 884: case SSH_AGENTC_ADD_RSA_ID_CONSTRAINED:
1.33 markus 885: process_add_identity(e, 1);
1.21 markus 886: break;
887: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 888: process_remove_identity(e, 1);
1.21 markus 889: break;
1.199 djm 890: #endif
1.21 markus 891: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.199 djm 892: process_remove_all_identities(e, 1); /* safe for !WITH_SSH1 */
1.33 markus 893: break;
894: /* ssh2 */
895: case SSH2_AGENTC_SIGN_REQUEST:
896: process_sign_request2(e);
897: break;
898: case SSH2_AGENTC_REQUEST_IDENTITIES:
899: process_request_identities(e, 2);
900: break;
901: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 902: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.33 markus 903: process_add_identity(e, 2);
904: break;
905: case SSH2_AGENTC_REMOVE_IDENTITY:
906: process_remove_identity(e, 2);
907: break;
908: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
909: process_remove_all_identities(e, 2);
1.21 markus 910: break;
1.163 markus 911: #ifdef ENABLE_PKCS11
1.59 markus 912: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 913: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 914: process_add_smartcard_key(e);
1.75 deraadt 915: break;
1.59 markus 916: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
917: process_remove_smartcard_key(e);
1.75 deraadt 918: break;
1.163 markus 919: #endif /* ENABLE_PKCS11 */
1.21 markus 920: default:
921: /* Unknown message. Respond with failure. */
922: error("Unknown message %d", type);
1.194 markus 923: sshbuf_reset(e->request);
924: send_status(e, 0);
1.21 markus 925: break;
926: }
1.1 deraadt 927: }
928:
1.55 itojun 929: static void
1.73 stevesk 930: new_socket(sock_type type, int fd)
1.1 deraadt 931: {
1.112 markus 932: u_int i, old_alloc, new_alloc;
1.96 deraadt 933:
1.119 djm 934: set_nonblock(fd);
1.21 markus 935:
936: if (fd > max_fd)
937: max_fd = fd;
938:
939: for (i = 0; i < sockets_alloc; i++)
940: if (sockets[i].type == AUTH_UNUSED) {
941: sockets[i].fd = fd;
1.194 markus 942: if ((sockets[i].input = sshbuf_new()) == NULL)
943: fatal("%s: sshbuf_new failed", __func__);
944: if ((sockets[i].output = sshbuf_new()) == NULL)
945: fatal("%s: sshbuf_new failed", __func__);
946: if ((sockets[i].request = sshbuf_new()) == NULL)
947: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 948: sockets[i].type = type;
1.21 markus 949: return;
950: }
951: old_alloc = sockets_alloc;
1.112 markus 952: new_alloc = sockets_alloc + 10;
1.200 deraadt 953: sockets = xreallocarray(sockets, new_alloc, sizeof(sockets[0]));
1.112 markus 954: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 955: sockets[i].type = AUTH_UNUSED;
1.112 markus 956: sockets_alloc = new_alloc;
1.21 markus 957: sockets[old_alloc].fd = fd;
1.194 markus 958: if ((sockets[old_alloc].input = sshbuf_new()) == NULL)
959: fatal("%s: sshbuf_new failed", __func__);
960: if ((sockets[old_alloc].output = sshbuf_new()) == NULL)
961: fatal("%s: sshbuf_new failed", __func__);
962: if ((sockets[old_alloc].request = sshbuf_new()) == NULL)
963: fatal("%s: sshbuf_new failed", __func__);
1.112 markus 964: sockets[old_alloc].type = type;
1.1 deraadt 965: }
966:
1.55 itojun 967: static int
1.155 dtucker 968: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, u_int *nallocp,
969: struct timeval **tvpp)
1.1 deraadt 970: {
1.174 dtucker 971: u_int i, sz;
1.46 markus 972: int n = 0;
1.155 dtucker 973: static struct timeval tv;
1.174 dtucker 974: time_t deadline;
1.46 markus 975:
976: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 977: switch (sockets[i].type) {
978: case AUTH_SOCKET:
979: case AUTH_CONNECTION:
1.214 ! deraadt 980: n = MAXIMUM(n, sockets[i].fd);
1.21 markus 981: break;
982: case AUTH_UNUSED:
983: break;
984: default:
985: fatal("Unknown socket type %d", sockets[i].type);
986: break;
987: }
1.46 markus 988: }
989:
990: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 991: if (*fdrp == NULL || sz > *nallocp) {
1.173 djm 992: free(*fdrp);
993: free(*fdwp);
1.46 markus 994: *fdrp = xmalloc(sz);
995: *fdwp = xmalloc(sz);
1.66 markus 996: *nallocp = sz;
1.46 markus 997: }
1.66 markus 998: if (n < *fdl)
999: debug("XXX shrink: %d < %d", n, *fdl);
1000: *fdl = n;
1.46 markus 1001: memset(*fdrp, 0, sz);
1002: memset(*fdwp, 0, sz);
1003:
1004: for (i = 0; i < sockets_alloc; i++) {
1005: switch (sockets[i].type) {
1006: case AUTH_SOCKET:
1007: case AUTH_CONNECTION:
1008: FD_SET(sockets[i].fd, *fdrp);
1.194 markus 1009: if (sshbuf_len(sockets[i].output) > 0)
1.46 markus 1010: FD_SET(sockets[i].fd, *fdwp);
1011: break;
1012: default:
1013: break;
1014: }
1015: }
1.155 dtucker 1016: deadline = reaper();
1017: if (parent_alive_interval != 0)
1018: deadline = (deadline == 0) ? parent_alive_interval :
1.214 ! deraadt 1019: MINIMUM(deadline, parent_alive_interval);
1.155 dtucker 1020: if (deadline == 0) {
1021: *tvpp = NULL;
1022: } else {
1023: tv.tv_sec = deadline;
1024: tv.tv_usec = 0;
1025: *tvpp = &tv;
1026: }
1.46 markus 1027: return (1);
1.21 markus 1028: }
1029:
1.55 itojun 1030: static void
1.21 markus 1031: after_select(fd_set *readset, fd_set *writeset)
1032: {
1.96 deraadt 1033: struct sockaddr_un sunaddr;
1.26 markus 1034: socklen_t slen;
1.21 markus 1035: char buf[1024];
1.194 markus 1036: int len, sock, r;
1.162 djm 1037: u_int i, orig_alloc;
1.103 markus 1038: uid_t euid;
1039: gid_t egid;
1.21 markus 1040:
1.162 djm 1041: for (i = 0, orig_alloc = sockets_alloc; i < orig_alloc; i++)
1.21 markus 1042: switch (sockets[i].type) {
1043: case AUTH_UNUSED:
1044: break;
1045: case AUTH_SOCKET:
1046: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 1047: slen = sizeof(sunaddr);
1.46 markus 1048: sock = accept(sockets[i].fd,
1.131 deraadt 1049: (struct sockaddr *)&sunaddr, &slen);
1.21 markus 1050: if (sock < 0) {
1.81 stevesk 1051: error("accept from AUTH_SOCKET: %s",
1052: strerror(errno));
1.103 markus 1053: break;
1054: }
1055: if (getpeereid(sock, &euid, &egid) < 0) {
1056: error("getpeereid %d failed: %s",
1057: sock, strerror(errno));
1058: close(sock);
1059: break;
1060: }
1.105 markus 1061: if ((euid != 0) && (getuid() != euid)) {
1.103 markus 1062: error("uid mismatch: "
1.104 stevesk 1063: "peer euid %u != uid %u",
1064: (u_int) euid, (u_int) getuid());
1.103 markus 1065: close(sock);
1.21 markus 1066: break;
1067: }
1068: new_socket(AUTH_CONNECTION, sock);
1069: }
1070: break;
1071: case AUTH_CONNECTION:
1.194 markus 1072: if (sshbuf_len(sockets[i].output) > 0 &&
1.21 markus 1073: FD_ISSET(sockets[i].fd, writeset)) {
1.162 djm 1074: len = write(sockets[i].fd,
1.194 markus 1075: sshbuf_ptr(sockets[i].output),
1076: sshbuf_len(sockets[i].output));
1.162 djm 1077: if (len == -1 && (errno == EAGAIN ||
1078: errno == EINTR))
1079: continue;
1.21 markus 1080: if (len <= 0) {
1.101 stevesk 1081: close_socket(&sockets[i]);
1.21 markus 1082: break;
1083: }
1.194 markus 1084: if ((r = sshbuf_consume(sockets[i].output,
1085: len)) != 0)
1086: fatal("%s: buffer error: %s",
1087: __func__, ssh_err(r));
1.21 markus 1088: }
1089: if (FD_ISSET(sockets[i].fd, readset)) {
1.162 djm 1090: len = read(sockets[i].fd, buf, sizeof(buf));
1091: if (len == -1 && (errno == EAGAIN ||
1092: errno == EINTR))
1093: continue;
1.21 markus 1094: if (len <= 0) {
1.101 stevesk 1095: close_socket(&sockets[i]);
1.21 markus 1096: break;
1097: }
1.194 markus 1098: if ((r = sshbuf_put(sockets[i].input,
1099: buf, len)) != 0)
1100: fatal("%s: buffer error: %s",
1101: __func__, ssh_err(r));
1.190 dtucker 1102: explicit_bzero(buf, sizeof(buf));
1.21 markus 1103: process_message(&sockets[i]);
1104: }
1105: break;
1106: default:
1107: fatal("Unknown type %d", sockets[i].type);
1108: }
1.1 deraadt 1109: }
1110:
1.55 itojun 1111: static void
1.113 markus 1112: cleanup_socket(void)
1.15 markus 1113: {
1.187 djm 1114: if (cleanup_pid != 0 && getpid() != cleanup_pid)
1115: return;
1116: debug("%s: cleanup", __func__);
1.48 deraadt 1117: if (socket_name[0])
1118: unlink(socket_name);
1119: if (socket_dir[0])
1120: rmdir(socket_dir);
1.10 markus 1121: }
1122:
1.114 markus 1123: void
1.15 markus 1124: cleanup_exit(int i)
1125: {
1.113 markus 1126: cleanup_socket();
1127: _exit(i);
1.15 markus 1128: }
1129:
1.135 deraadt 1130: /*ARGSUSED*/
1.55 itojun 1131: static void
1.48 deraadt 1132: cleanup_handler(int sig)
1133: {
1.113 markus 1134: cleanup_socket();
1.163 markus 1135: #ifdef ENABLE_PKCS11
1136: pkcs11_terminate();
1137: #endif
1.48 deraadt 1138: _exit(2);
1.113 markus 1139: }
1140:
1.68 markus 1141: static void
1.155 dtucker 1142: check_parent_exists(void)
1.68 markus 1143: {
1.172 dtucker 1144: /*
1145: * If our parent has exited then getppid() will return (pid_t)1,
1146: * so testing for that should be safe.
1147: */
1148: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 1149: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1150: cleanup_socket();
1151: _exit(2);
1.68 markus 1152: }
1.48 deraadt 1153: }
1154:
1.55 itojun 1155: static void
1.50 itojun 1156: usage(void)
1.15 markus 1157: {
1.184 deraadt 1158: fprintf(stderr,
1.202 jmc 1159: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.193 jmc 1160: " [-t life] [command [arg ...]]\n"
1.184 deraadt 1161: " ssh-agent [-c | -s] -k\n");
1.21 markus 1162: exit(1);
1.15 markus 1163: }
1164:
1.2 provos 1165: int
1166: main(int ac, char **av)
1.1 deraadt 1167: {
1.201 djm 1168: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.154 dtucker 1169: int sock, fd, ch, result, saved_errno;
1.120 avsm 1170: u_int nalloc;
1.96 deraadt 1171: char *shell, *format, *pidstr, *agentsocket = NULL;
1172: fd_set *readsetp = NULL, *writesetp = NULL;
1.41 markus 1173: struct rlimit rlim;
1.96 deraadt 1174: extern int optind;
1.98 stevesk 1175: extern char *optarg;
1.21 markus 1176: pid_t pid;
1.96 deraadt 1177: char pidstrbuf[1 + 3 * sizeof pid];
1.155 dtucker 1178: struct timeval *tvp = NULL;
1.161 tobias 1179: size_t len;
1.189 djm 1180: mode_t prev_mask;
1.123 djm 1181:
1.212 dtucker 1182: ssh_malloc_init(); /* must be called before any mallocs */
1.123 djm 1183: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
1184: sanitise_stdfd();
1.99 markus 1185:
1186: /* drop */
1187: setegid(getgid());
1188: setgid(getgid());
1.53 markus 1189:
1.185 markus 1190: #ifdef WITH_OPENSSL
1.170 djm 1191: OpenSSL_add_all_algorithms();
1.185 markus 1192: #endif
1.21 markus 1193:
1.201 djm 1194: while ((ch = getopt(ac, av, "cDdksE:a:t:")) != -1) {
1.21 markus 1195: switch (ch) {
1.192 djm 1196: case 'E':
1197: fingerprint_hash = ssh_digest_alg_by_name(optarg);
1198: if (fingerprint_hash == -1)
1199: fatal("Invalid hash algorithm \"%s\"", optarg);
1200: break;
1.21 markus 1201: case 'c':
1202: if (s_flag)
1203: usage();
1204: c_flag++;
1205: break;
1206: case 'k':
1207: k_flag++;
1208: break;
1209: case 's':
1210: if (c_flag)
1211: usage();
1212: s_flag++;
1213: break;
1.57 markus 1214: case 'd':
1.201 djm 1215: if (d_flag || D_flag)
1.57 markus 1216: usage();
1217: d_flag++;
1218: break;
1.201 djm 1219: case 'D':
1220: if (d_flag || D_flag)
1221: usage();
1222: D_flag++;
1223: break;
1.86 markus 1224: case 'a':
1225: agentsocket = optarg;
1.106 marc 1226: break;
1227: case 't':
1228: if ((lifetime = convtime(optarg)) == -1) {
1229: fprintf(stderr, "Invalid lifetime\n");
1230: usage();
1231: }
1.86 markus 1232: break;
1.21 markus 1233: default:
1234: usage();
1235: }
1236: }
1237: ac -= optind;
1238: av += optind;
1239:
1.201 djm 1240: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 1241: usage();
1242:
1.85 markus 1243: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1244: shell = getenv("SHELL");
1.161 tobias 1245: if (shell != NULL && (len = strlen(shell)) > 2 &&
1246: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 1247: c_flag = 1;
1248: }
1249: if (k_flag) {
1.136 deraadt 1250: const char *errstr = NULL;
1251:
1.21 markus 1252: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1253: if (pidstr == NULL) {
1254: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1255: SSH_AGENTPID_ENV_NAME);
1.21 markus 1256: exit(1);
1257: }
1.136 deraadt 1258: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
1259: if (errstr) {
1260: fprintf(stderr,
1261: "%s=\"%s\", which is not a good PID: %s\n",
1262: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 1263: exit(1);
1264: }
1265: if (kill(pid, SIGTERM) == -1) {
1266: perror("kill");
1267: exit(1);
1268: }
1269: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 1270: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1271: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1272: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1273: exit(0);
1274: }
1275: parent_pid = getpid();
1276:
1.86 markus 1277: if (agentsocket == NULL) {
1278: /* Create private directory for agent socket */
1.171 djm 1279: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 1280: if (mkdtemp(socket_dir) == NULL) {
1281: perror("mkdtemp: private socket dir");
1282: exit(1);
1283: }
1.91 mpech 1284: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1285: (long)parent_pid);
1.86 markus 1286: } else {
1287: /* Try to use specified agent socket */
1288: socket_dir[0] = '\0';
1289: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1290: }
1291:
1.23 markus 1292: /*
1293: * Create socket early so it will exist before command gets run from
1294: * the parent.
1295: */
1.189 djm 1296: prev_mask = umask(0177);
1.188 millert 1297: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 1298: if (sock < 0) {
1.188 millert 1299: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 1300: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 1301: cleanup_exit(1);
1302: }
1.189 djm 1303: umask(prev_mask);
1.46 markus 1304:
1.23 markus 1305: /*
1306: * Fork, and have the parent execute the command, if any, or present
1307: * the socket data. The child continues as the authentication agent.
1308: */
1.201 djm 1309: if (D_flag || d_flag) {
1310: log_init(__progname,
1311: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
1312: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 1313: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1314: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1315: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1316: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 1317: fflush(stdout);
1.57 markus 1318: goto skip;
1319: }
1.21 markus 1320: pid = fork();
1321: if (pid == -1) {
1322: perror("fork");
1.81 stevesk 1323: cleanup_exit(1);
1.21 markus 1324: }
1325: if (pid != 0) { /* Parent - execute the given command. */
1326: close(sock);
1.91 mpech 1327: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1328: if (ac == 0) {
1329: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1330: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1331: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1332: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1333: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1334: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1335: exit(0);
1336: }
1.36 deraadt 1337: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1338: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1339: perror("setenv");
1340: exit(1);
1341: }
1.21 markus 1342: execvp(av[0], av);
1343: perror(av[0]);
1344: exit(1);
1345: }
1.81 stevesk 1346: /* child */
1347: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1348:
1349: if (setsid() == -1) {
1.81 stevesk 1350: error("setsid: %s", strerror(errno));
1.67 stevesk 1351: cleanup_exit(1);
1352: }
1353:
1354: (void)chdir("/");
1.107 markus 1355: if ((fd = open(_PATH_DEVNULL, O_RDWR, 0)) != -1) {
1356: /* XXX might close listen socket */
1357: (void)dup2(fd, STDIN_FILENO);
1358: (void)dup2(fd, STDOUT_FILENO);
1359: (void)dup2(fd, STDERR_FILENO);
1360: if (fd > 2)
1361: close(fd);
1362: }
1.21 markus 1363:
1.41 markus 1364: /* deny core dumps, since memory contains unencrypted private keys */
1365: rlim.rlim_cur = rlim.rlim_max = 0;
1366: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1367: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1368: cleanup_exit(1);
1369: }
1.57 markus 1370:
1371: skip:
1.187 djm 1372:
1373: cleanup_pid = getpid();
1.163 markus 1374:
1375: #ifdef ENABLE_PKCS11
1376: pkcs11_init(0);
1377: #endif
1.21 markus 1378: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 1379: if (ac > 0)
1380: parent_alive_interval = 10;
1.33 markus 1381: idtab_init();
1.61 markus 1382: signal(SIGPIPE, SIG_IGN);
1.201 djm 1383: signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
1.48 deraadt 1384: signal(SIGHUP, cleanup_handler);
1385: signal(SIGTERM, cleanup_handler);
1.66 markus 1386: nalloc = 0;
1.205 djm 1387:
1.211 doug 1388: if (pledge("stdio cpath unix id proc exec", NULL) == -1)
1.205 djm 1389: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 1390:
1.21 markus 1391: while (1) {
1.155 dtucker 1392: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc, &tvp);
1393: result = select(max_fd + 1, readsetp, writesetp, NULL, tvp);
1.154 dtucker 1394: saved_errno = errno;
1.155 dtucker 1395: if (parent_alive_interval != 0)
1396: check_parent_exists();
1397: (void) reaper(); /* remove expired keys */
1.154 dtucker 1398: if (result < 0) {
1399: if (saved_errno == EINTR)
1.21 markus 1400: continue;
1.154 dtucker 1401: fatal("select: %s", strerror(saved_errno));
1402: } else if (result > 0)
1403: after_select(readsetp, writesetp);
1.15 markus 1404: }
1.21 markus 1405: /* NOTREACHED */
1.1 deraadt 1406: }