Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.90
1.1 deraadt 1: /*
1.22 deraadt 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: * The authentication agent program.
1.33 markus 6: *
1.35 deraadt 7: * As far as I am concerned, the code I have written for this software
8: * can be used freely for any purpose. Any derived versions of this
9: * software must be clearly marked as such, and if the derived work is
10: * incompatible with the protocol description in the RFC file, it must be
11: * called by a name other than "ssh" or "Secure Shell".
12: *
1.56 markus 13: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.35 deraadt 14: *
15: * Redistribution and use in source and binary forms, with or without
16: * modification, are permitted provided that the following conditions
17: * are met:
18: * 1. Redistributions of source code must retain the above copyright
19: * notice, this list of conditions and the following disclaimer.
20: * 2. Redistributions in binary form must reproduce the above copyright
21: * notice, this list of conditions and the following disclaimer in the
22: * documentation and/or other materials provided with the distribution.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.22 deraadt 34: */
1.1 deraadt 35:
36: #include "includes.h"
1.78 provos 37: #include <sys/queue.h>
1.90 ! markus 38: RCSID("$OpenBSD: ssh-agent.c,v 1.89 2002/06/05 21:55:44 markus Exp $");
1.47 markus 39:
40: #include <openssl/evp.h>
41: #include <openssl/md5.h>
1.1 deraadt 42:
43: #include "ssh.h"
44: #include "rsa.h"
45: #include "buffer.h"
46: #include "bufaux.h"
47: #include "xmalloc.h"
48: #include "getput.h"
1.32 markus 49: #include "key.h"
50: #include "authfd.h"
1.37 markus 51: #include "compat.h"
1.47 markus 52: #include "log.h"
1.7 deraadt 53:
1.59 markus 54: #ifdef SMARTCARD
55: #include "scard.h"
1.71 jakob 56: #endif
1.59 markus 57:
1.73 stevesk 58: typedef enum {
59: AUTH_UNUSED,
60: AUTH_SOCKET,
61: AUTH_CONNECTION
62: } sock_type;
63:
1.21 markus 64: typedef struct {
65: int fd;
1.73 stevesk 66: sock_type type;
1.21 markus 67: Buffer input;
68: Buffer output;
1.87 markus 69: Buffer request;
1.1 deraadt 70: } SocketEntry;
71:
1.45 markus 72: u_int sockets_alloc = 0;
1.1 deraadt 73: SocketEntry *sockets = NULL;
74:
1.78 provos 75: typedef struct identity {
76: TAILQ_ENTRY(identity) next;
1.33 markus 77: Key *key;
1.21 markus 78: char *comment;
1.89 markus 79: u_int death;
1.1 deraadt 80: } Identity;
81:
1.33 markus 82: typedef struct {
83: int nentries;
1.78 provos 84: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 85: } Idtab;
86:
87: /* private key table, one per protocol version */
88: Idtab idtable[3];
1.1 deraadt 89:
90: int max_fd = 0;
91:
1.11 markus 92: /* pid of shell == parent of agent */
1.29 deraadt 93: pid_t parent_pid = -1;
1.10 markus 94:
95: /* pathname and directory for AUTH_SOCKET */
96: char socket_name[1024];
97: char socket_dir[1024];
98:
1.88 markus 99: /* locking */
100: int locked = 0;
101: char *lock_passwd = NULL;
102:
1.20 markus 103: extern char *__progname;
104:
1.55 itojun 105: static void
1.33 markus 106: idtab_init(void)
1.1 deraadt 107: {
1.33 markus 108: int i;
1.74 deraadt 109: for (i = 0; i <=2; i++) {
1.78 provos 110: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 111: idtable[i].nentries = 0;
112: }
113: }
114:
115: /* return private key table for requested protocol version */
1.55 itojun 116: static Idtab *
1.33 markus 117: idtab_lookup(int version)
118: {
119: if (version < 1 || version > 2)
120: fatal("internal error, bad protocol version %d", version);
121: return &idtable[version];
122: }
123:
1.89 markus 124: static void
125: free_identity(Identity *id)
126: {
127: key_free(id->key);
128: xfree(id->comment);
129: xfree(id);
130: }
131:
1.33 markus 132: /* return matching private key for given public key */
1.78 provos 133: static Identity *
134: lookup_identity(Key *key, int version)
1.33 markus 135: {
1.78 provos 136: Identity *id;
137:
1.33 markus 138: Idtab *tab = idtab_lookup(version);
1.78 provos 139: TAILQ_FOREACH(id, &tab->idlist, next) {
140: if (key_equal(key, id->key))
141: return (id);
1.33 markus 142: }
1.78 provos 143: return (NULL);
144: }
145:
1.33 markus 146: /* send list of supported public keys to 'client' */
1.55 itojun 147: static void
1.33 markus 148: process_request_identities(SocketEntry *e, int version)
149: {
150: Idtab *tab = idtab_lookup(version);
1.21 markus 151: Buffer msg;
1.78 provos 152: Identity *id;
1.1 deraadt 153:
1.21 markus 154: buffer_init(&msg);
1.33 markus 155: buffer_put_char(&msg, (version == 1) ?
156: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
157: buffer_put_int(&msg, tab->nentries);
1.78 provos 158: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 159: if (id->key->type == KEY_RSA1) {
1.33 markus 160: buffer_put_int(&msg, BN_num_bits(id->key->rsa->n));
161: buffer_put_bignum(&msg, id->key->rsa->e);
162: buffer_put_bignum(&msg, id->key->rsa->n);
163: } else {
1.45 markus 164: u_char *blob;
165: u_int blen;
1.39 markus 166: key_to_blob(id->key, &blob, &blen);
1.33 markus 167: buffer_put_string(&msg, blob, blen);
168: xfree(blob);
169: }
170: buffer_put_cstring(&msg, id->comment);
1.21 markus 171: }
172: buffer_put_int(&e->output, buffer_len(&msg));
173: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
174: buffer_free(&msg);
1.1 deraadt 175: }
176:
1.33 markus 177: /* ssh1 only */
1.55 itojun 178: static void
1.33 markus 179: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 180: {
1.78 provos 181: Identity *id;
182: Key *key;
1.33 markus 183: BIGNUM *challenge;
184: int i, len;
1.21 markus 185: Buffer msg;
186: MD5_CTX md;
1.45 markus 187: u_char buf[32], mdbuf[16], session_id[16];
188: u_int response_type;
1.21 markus 189:
190: buffer_init(&msg);
1.39 markus 191: key = key_new(KEY_RSA1);
1.76 markus 192: if ((challenge = BN_new()) == NULL)
193: fatal("process_authentication_challenge1: BN_new failed");
1.33 markus 194:
1.87 markus 195: buffer_get_int(&e->request); /* ignored */
196: buffer_get_bignum(&e->request, key->rsa->e);
197: buffer_get_bignum(&e->request, key->rsa->n);
198: buffer_get_bignum(&e->request, challenge);
1.21 markus 199:
1.33 markus 200: /* Only protocol 1.1 is supported */
1.87 markus 201: if (buffer_len(&e->request) == 0)
1.33 markus 202: goto failure;
1.87 markus 203: buffer_get(&e->request, session_id, 16);
204: response_type = buffer_get_int(&e->request);
1.33 markus 205: if (response_type != 1)
206: goto failure;
207:
1.78 provos 208: id = lookup_identity(key, 1);
209: if (id != NULL) {
210: Key *private = id->key;
1.33 markus 211: /* Decrypt the challenge using the private key. */
1.49 markus 212: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
213: goto failure;
1.33 markus 214:
215: /* The response is MD5 of decrypted challenge plus session id. */
216: len = BN_num_bytes(challenge);
217: if (len <= 0 || len > 32) {
218: log("process_authentication_challenge: bad challenge length %d", len);
219: goto failure;
220: }
221: memset(buf, 0, 32);
222: BN_bn2bin(challenge, buf + 32 - len);
223: MD5_Init(&md);
224: MD5_Update(&md, buf, 32);
225: MD5_Update(&md, session_id, 16);
226: MD5_Final(mdbuf, &md);
227:
228: /* Send the response. */
229: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
230: for (i = 0; i < 16; i++)
231: buffer_put_char(&msg, mdbuf[i]);
232: goto send;
233: }
1.21 markus 234:
1.33 markus 235: failure:
236: /* Unknown identity or protocol error. Send failure. */
1.21 markus 237: buffer_put_char(&msg, SSH_AGENT_FAILURE);
238: send:
239: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 240: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
241: key_free(key);
242: BN_clear_free(challenge);
243: buffer_free(&msg);
244: }
245:
246: /* ssh2 only */
1.55 itojun 247: static void
1.33 markus 248: process_sign_request2(SocketEntry *e)
249: {
250: extern int datafellows;
1.78 provos 251: Key *key;
1.45 markus 252: u_char *blob, *data, *signature = NULL;
253: u_int blen, dlen, slen = 0;
1.37 markus 254: int flags;
1.33 markus 255: Buffer msg;
256: int ok = -1;
257:
258: datafellows = 0;
1.43 markus 259:
1.87 markus 260: blob = buffer_get_string(&e->request, &blen);
261: data = buffer_get_string(&e->request, &dlen);
1.37 markus 262:
1.87 markus 263: flags = buffer_get_int(&e->request);
1.37 markus 264: if (flags & SSH_AGENT_OLD_SIGNATURE)
265: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 266:
1.39 markus 267: key = key_from_blob(blob, blen);
1.33 markus 268: if (key != NULL) {
1.78 provos 269: Identity *id = lookup_identity(key, 2);
270: if (id != NULL)
271: ok = key_sign(id->key, &signature, &slen, data, dlen);
1.33 markus 272: }
273: key_free(key);
274: buffer_init(&msg);
275: if (ok == 0) {
276: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
277: buffer_put_string(&msg, signature, slen);
278: } else {
279: buffer_put_char(&msg, SSH_AGENT_FAILURE);
280: }
281: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 282: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 283: buffer_len(&msg));
1.21 markus 284: buffer_free(&msg);
1.33 markus 285: xfree(data);
286: xfree(blob);
287: if (signature != NULL)
288: xfree(signature);
1.1 deraadt 289: }
290:
1.33 markus 291: /* shared */
1.55 itojun 292: static void
1.33 markus 293: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 294: {
1.78 provos 295: Key *key = NULL;
1.45 markus 296: u_char *blob;
297: u_int blen;
298: u_int bits;
1.33 markus 299: int success = 0;
1.21 markus 300:
1.74 deraadt 301: switch (version) {
1.33 markus 302: case 1:
1.39 markus 303: key = key_new(KEY_RSA1);
1.87 markus 304: bits = buffer_get_int(&e->request);
305: buffer_get_bignum(&e->request, key->rsa->e);
306: buffer_get_bignum(&e->request, key->rsa->n);
1.33 markus 307:
308: if (bits != key_size(key))
309: log("Warning: identity keysize mismatch: actual %d, announced %d",
1.46 markus 310: key_size(key), bits);
1.33 markus 311: break;
312: case 2:
1.87 markus 313: blob = buffer_get_string(&e->request, &blen);
1.39 markus 314: key = key_from_blob(blob, blen);
1.33 markus 315: xfree(blob);
316: break;
317: }
318: if (key != NULL) {
1.78 provos 319: Identity *id = lookup_identity(key, version);
320: if (id != NULL) {
1.23 markus 321: /*
322: * We have this key. Free the old key. Since we
323: * don\'t want to leave empty slots in the middle of
1.40 markus 324: * the array, we actually free the key there and move
325: * all the entries between the empty slot and the end
326: * of the array.
1.23 markus 327: */
1.33 markus 328: Idtab *tab = idtab_lookup(version);
1.38 markus 329: if (tab->nentries < 1)
330: fatal("process_remove_identity: "
331: "internal error: tab->nentries %d",
332: tab->nentries);
1.78 provos 333: TAILQ_REMOVE(&tab->idlist, id, next);
334: free_identity(id);
1.33 markus 335: tab->nentries--;
336: success = 1;
1.21 markus 337: }
1.33 markus 338: key_free(key);
339: }
1.1 deraadt 340: buffer_put_int(&e->output, 1);
1.33 markus 341: buffer_put_char(&e->output,
342: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 343: }
344:
1.55 itojun 345: static void
1.33 markus 346: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 347: {
1.33 markus 348: Idtab *tab = idtab_lookup(version);
1.78 provos 349: Identity *id;
1.21 markus 350:
351: /* Loop over all identities and clear the keys. */
1.78 provos 352: for (id = TAILQ_FIRST(&tab->idlist); id;
353: id = TAILQ_FIRST(&tab->idlist)) {
354: TAILQ_REMOVE(&tab->idlist, id, next);
355: free_identity(id);
1.21 markus 356: }
357:
358: /* Mark that there are no identities. */
1.33 markus 359: tab->nentries = 0;
1.21 markus 360:
361: /* Send success. */
362: buffer_put_int(&e->output, 1);
363: buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
364: return;
1.1 deraadt 365: }
366:
1.55 itojun 367: static void
1.89 markus 368: reaper(void)
369: {
370: Idtab *tab;
371: Identity *id, *nxt;
372: int version;
373: u_int now = time(NULL);
374:
375: for (version = 1; version < 3; version++) {
376: tab = idtab_lookup(version);
377: for (id = TAILQ_FIRST(&tab->idlist); id; id = nxt) {
378: nxt = TAILQ_NEXT(id, next);
379: if (id->death != 0 && now >= id->death) {
380: TAILQ_REMOVE(&tab->idlist, id, next);
381: free_identity(id);
382: tab->nentries--;
383: }
384: }
385: }
386: }
387:
388: static void
1.33 markus 389: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 390: {
1.33 markus 391: Key *k = NULL;
1.39 markus 392: char *type_name;
1.33 markus 393: char *comment;
1.39 markus 394: int type, success = 0;
1.33 markus 395: Idtab *tab = idtab_lookup(version);
396:
397: switch (version) {
398: case 1:
1.39 markus 399: k = key_new_private(KEY_RSA1);
1.87 markus 400: buffer_get_int(&e->request); /* ignored */
401: buffer_get_bignum(&e->request, k->rsa->n);
402: buffer_get_bignum(&e->request, k->rsa->e);
403: buffer_get_bignum(&e->request, k->rsa->d);
404: buffer_get_bignum(&e->request, k->rsa->iqmp);
1.33 markus 405:
406: /* SSH and SSL have p and q swapped */
1.87 markus 407: buffer_get_bignum(&e->request, k->rsa->q); /* p */
408: buffer_get_bignum(&e->request, k->rsa->p); /* q */
1.33 markus 409:
410: /* Generate additional parameters */
1.60 markus 411: rsa_generate_additional_parameters(k->rsa);
1.33 markus 412: break;
413: case 2:
1.87 markus 414: type_name = buffer_get_string(&e->request, NULL);
1.46 markus 415: type = key_type_from_name(type_name);
1.39 markus 416: xfree(type_name);
1.74 deraadt 417: switch (type) {
1.39 markus 418: case KEY_DSA:
419: k = key_new_private(type);
1.87 markus 420: buffer_get_bignum2(&e->request, k->dsa->p);
421: buffer_get_bignum2(&e->request, k->dsa->q);
422: buffer_get_bignum2(&e->request, k->dsa->g);
423: buffer_get_bignum2(&e->request, k->dsa->pub_key);
424: buffer_get_bignum2(&e->request, k->dsa->priv_key);
1.39 markus 425: break;
426: case KEY_RSA:
427: k = key_new_private(type);
1.87 markus 428: buffer_get_bignum2(&e->request, k->rsa->n);
429: buffer_get_bignum2(&e->request, k->rsa->e);
430: buffer_get_bignum2(&e->request, k->rsa->d);
431: buffer_get_bignum2(&e->request, k->rsa->iqmp);
432: buffer_get_bignum2(&e->request, k->rsa->p);
433: buffer_get_bignum2(&e->request, k->rsa->q);
1.39 markus 434:
435: /* Generate additional parameters */
1.60 markus 436: rsa_generate_additional_parameters(k->rsa);
1.39 markus 437: break;
438: default:
1.87 markus 439: buffer_clear(&e->request);
1.33 markus 440: goto send;
1.21 markus 441: }
1.33 markus 442: break;
443: }
1.87 markus 444: comment = buffer_get_string(&e->request, NULL);
1.33 markus 445: if (k == NULL) {
446: xfree(comment);
447: goto send;
448: }
449: success = 1;
1.78 provos 450: if (lookup_identity(k, version) == NULL) {
451: Identity *id = xmalloc(sizeof(Identity));
452: id->key = k;
453: id->comment = comment;
1.89 markus 454: id->death = 0;
1.78 provos 455: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 456: /* Increment the number of identities. */
457: tab->nentries++;
458: } else {
459: key_free(k);
460: xfree(comment);
461: }
462: send:
1.1 deraadt 463: buffer_put_int(&e->output, 1);
1.33 markus 464: buffer_put_char(&e->output,
465: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 466: }
467:
1.89 markus 468: static void
469: process_lifetime_identity(SocketEntry *e, int version)
470: {
471: Key *key = NULL;
472: u_char *blob;
473: u_int blen, bits, death;
474: int success = 0;
475:
476: death = time(NULL) + buffer_get_int(&e->request);
477:
478: switch (version) {
479: case 1:
480: key = key_new(KEY_RSA1);
481: bits = buffer_get_int(&e->request);
482: buffer_get_bignum(&e->request, key->rsa->e);
483: buffer_get_bignum(&e->request, key->rsa->n);
484:
485: break;
486: case 2:
487: blob = buffer_get_string(&e->request, &blen);
488: key = key_from_blob(blob, blen);
489: xfree(blob);
490: break;
491: }
492: if (key != NULL) {
493: Identity *id = lookup_identity(key, version);
494: if (id != NULL && id->death == 0) {
495: id->death = death;
496: success = 1;
497: }
498: key_free(key);
499: }
500: buffer_put_int(&e->output, 1);
501: buffer_put_char(&e->output,
502: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
503: }
504:
1.88 markus 505: /* XXX todo: encrypt sensitive data with passphrase */
506: static void
507: process_lock_agent(SocketEntry *e, int lock)
508: {
509: char *passwd;
510: int success = 0;
511:
512: passwd = buffer_get_string(&e->request, NULL);
513: if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
514: locked = 0;
515: memset(lock_passwd, 0, strlen(lock_passwd));
516: xfree(lock_passwd);
517: lock_passwd = NULL;
518: success = 1;
519: } else if (!locked && lock) {
520: locked = 1;
521: lock_passwd = xstrdup(passwd);
522: success = 1;
523: }
524: memset(passwd, 0, strlen(passwd));
525: xfree(passwd);
526:
527: buffer_put_int(&e->output, 1);
528: buffer_put_char(&e->output,
529: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
530: return;
531: }
532:
533: static void
534: no_identities(SocketEntry *e, u_int type)
535: {
536: Buffer msg;
537:
538: buffer_init(&msg);
539: buffer_put_char(&msg,
540: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
541: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
542: buffer_put_int(&msg, 0);
543: buffer_put_int(&e->output, buffer_len(&msg));
544: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
545: buffer_free(&msg);
546: }
1.59 markus 547:
548: #ifdef SMARTCARD
549: static void
550: process_add_smartcard_key (SocketEntry *e)
551: {
1.84 markus 552: Identity *id;
1.59 markus 553: Idtab *tab;
1.84 markus 554: Key **keys, *k;
1.83 rees 555: char *sc_reader_id = NULL, *pin;
1.84 markus 556: int i, version, success = 0;
1.75 deraadt 557:
1.87 markus 558: sc_reader_id = buffer_get_string(&e->request, NULL);
559: pin = buffer_get_string(&e->request, NULL);
1.84 markus 560: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 561: xfree(sc_reader_id);
1.83 rees 562: xfree(pin);
1.59 markus 563:
1.84 markus 564: if (keys == NULL || keys[0] == NULL) {
565: error("sc_get_keys failed");
1.59 markus 566: goto send;
567: }
1.84 markus 568: for (i = 0; keys[i] != NULL; i++) {
569: k = keys[i];
570: version = k->type == KEY_RSA1 ? 1 : 2;
571: tab = idtab_lookup(version);
572: if (lookup_identity(k, version) == NULL) {
573: id = xmalloc(sizeof(Identity));
574: id->key = k;
575: id->comment = xstrdup("smartcard key");
1.89 markus 576: id->death = 0;
1.84 markus 577: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
578: tab->nentries++;
579: success = 1;
580: } else {
581: key_free(k);
582: }
583: keys[i] = NULL;
1.59 markus 584: }
1.84 markus 585: xfree(keys);
1.59 markus 586: send:
587: buffer_put_int(&e->output, 1);
588: buffer_put_char(&e->output,
589: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
590: }
591:
592: static void
593: process_remove_smartcard_key(SocketEntry *e)
594: {
1.84 markus 595: Identity *id;
596: Idtab *tab;
597: Key **keys, *k = NULL;
1.83 rees 598: char *sc_reader_id = NULL, *pin;
1.84 markus 599: int i, version, success = 0;
1.59 markus 600:
1.87 markus 601: sc_reader_id = buffer_get_string(&e->request, NULL);
602: pin = buffer_get_string(&e->request, NULL);
1.84 markus 603: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 604: xfree(sc_reader_id);
1.83 rees 605: xfree(pin);
1.59 markus 606:
1.84 markus 607: if (keys == NULL || keys[0] == NULL) {
608: error("sc_get_keys failed");
609: goto send;
610: }
611: for (i = 0; keys[i] != NULL; i++) {
612: k = keys[i];
613: version = k->type == KEY_RSA1 ? 1 : 2;
614: if ((id = lookup_identity(k, version)) != NULL) {
615: tab = idtab_lookup(version);
1.90 ! markus 616: TAILQ_REMOVE(&tab->idlist, id, next);
1.59 markus 617: tab->nentries--;
1.78 provos 618: free_identity(id);
1.59 markus 619: success = 1;
620: }
621: key_free(k);
1.84 markus 622: keys[i] = NULL;
1.59 markus 623: }
1.84 markus 624: xfree(keys);
625: send:
1.59 markus 626: buffer_put_int(&e->output, 1);
627: buffer_put_char(&e->output,
628: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
629: }
1.70 jakob 630: #endif /* SMARTCARD */
1.59 markus 631:
1.33 markus 632: /* dispatch incoming messages */
633:
1.55 itojun 634: static void
1.2 provos 635: process_message(SocketEntry *e)
1.1 deraadt 636: {
1.45 markus 637: u_int msg_len;
638: u_int type;
639: u_char *cp;
1.89 markus 640:
641: /* kill dead keys */
642: reaper();
643:
1.21 markus 644: if (buffer_len(&e->input) < 5)
645: return; /* Incomplete message. */
1.77 stevesk 646: cp = buffer_ptr(&e->input);
1.21 markus 647: msg_len = GET_32BIT(cp);
648: if (msg_len > 256 * 1024) {
649: shutdown(e->fd, SHUT_RDWR);
650: close(e->fd);
651: e->type = AUTH_UNUSED;
1.87 markus 652: buffer_free(&e->input);
653: buffer_free(&e->output);
654: buffer_free(&e->request);
1.21 markus 655: return;
656: }
657: if (buffer_len(&e->input) < msg_len + 4)
658: return;
1.87 markus 659:
660: /* move the current input to e->request */
1.21 markus 661: buffer_consume(&e->input, 4);
1.87 markus 662: buffer_clear(&e->request);
663: buffer_append(&e->request, buffer_ptr(&e->input), msg_len);
664: buffer_consume(&e->input, msg_len);
665: type = buffer_get_char(&e->request);
1.21 markus 666:
1.88 markus 667: /* check wheter agent is locked */
668: if (locked && type != SSH_AGENTC_UNLOCK) {
669: buffer_clear(&e->request);
670: switch (type) {
671: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
672: case SSH2_AGENTC_REQUEST_IDENTITIES:
673: /* send empty lists */
674: no_identities(e, type);
675: break;
676: default:
677: /* send a fail message for all other request types */
678: buffer_put_int(&e->output, 1);
679: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
680: }
681: return;
682: }
683:
1.59 markus 684: debug("type %d", type);
1.21 markus 685: switch (type) {
1.88 markus 686: case SSH_AGENTC_LOCK:
687: case SSH_AGENTC_UNLOCK:
688: process_lock_agent(e, type == SSH_AGENTC_LOCK);
689: break;
1.33 markus 690: /* ssh1 */
691: case SSH_AGENTC_RSA_CHALLENGE:
692: process_authentication_challenge1(e);
693: break;
1.21 markus 694: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 695: process_request_identities(e, 1);
1.21 markus 696: break;
697: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 698: process_add_identity(e, 1);
1.21 markus 699: break;
700: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 701: process_remove_identity(e, 1);
1.21 markus 702: break;
703: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 704: process_remove_all_identities(e, 1);
705: break;
1.89 markus 706: case SSH_AGENTC_LIFETIME_IDENTITY1:
707: process_lifetime_identity(e, 1);
708: break;
1.33 markus 709: /* ssh2 */
710: case SSH2_AGENTC_SIGN_REQUEST:
711: process_sign_request2(e);
712: break;
713: case SSH2_AGENTC_REQUEST_IDENTITIES:
714: process_request_identities(e, 2);
715: break;
716: case SSH2_AGENTC_ADD_IDENTITY:
717: process_add_identity(e, 2);
718: break;
719: case SSH2_AGENTC_REMOVE_IDENTITY:
720: process_remove_identity(e, 2);
721: break;
722: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
723: process_remove_all_identities(e, 2);
1.89 markus 724: break;
725: case SSH_AGENTC_LIFETIME_IDENTITY:
726: process_lifetime_identity(e, 2);
1.21 markus 727: break;
1.59 markus 728: #ifdef SMARTCARD
729: case SSH_AGENTC_ADD_SMARTCARD_KEY:
730: process_add_smartcard_key(e);
1.75 deraadt 731: break;
1.59 markus 732: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
733: process_remove_smartcard_key(e);
1.75 deraadt 734: break;
1.70 jakob 735: #endif /* SMARTCARD */
1.21 markus 736: default:
737: /* Unknown message. Respond with failure. */
738: error("Unknown message %d", type);
1.87 markus 739: buffer_clear(&e->request);
1.21 markus 740: buffer_put_int(&e->output, 1);
741: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
742: break;
743: }
1.1 deraadt 744: }
745:
1.55 itojun 746: static void
1.73 stevesk 747: new_socket(sock_type type, int fd)
1.1 deraadt 748: {
1.45 markus 749: u_int i, old_alloc;
1.21 markus 750: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
751: error("fcntl O_NONBLOCK: %s", strerror(errno));
752:
753: if (fd > max_fd)
754: max_fd = fd;
755:
756: for (i = 0; i < sockets_alloc; i++)
757: if (sockets[i].type == AUTH_UNUSED) {
758: sockets[i].fd = fd;
759: sockets[i].type = type;
760: buffer_init(&sockets[i].input);
761: buffer_init(&sockets[i].output);
1.87 markus 762: buffer_init(&sockets[i].request);
1.21 markus 763: return;
764: }
765: old_alloc = sockets_alloc;
766: sockets_alloc += 10;
767: if (sockets)
768: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
769: else
770: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
771: for (i = old_alloc; i < sockets_alloc; i++)
772: sockets[i].type = AUTH_UNUSED;
773: sockets[old_alloc].type = type;
774: sockets[old_alloc].fd = fd;
775: buffer_init(&sockets[old_alloc].input);
776: buffer_init(&sockets[old_alloc].output);
1.87 markus 777: buffer_init(&sockets[old_alloc].request);
1.1 deraadt 778: }
779:
1.55 itojun 780: static int
1.66 markus 781: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 782: {
1.46 markus 783: u_int i, sz;
784: int n = 0;
785:
786: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 787: switch (sockets[i].type) {
788: case AUTH_SOCKET:
789: case AUTH_CONNECTION:
1.46 markus 790: n = MAX(n, sockets[i].fd);
1.21 markus 791: break;
792: case AUTH_UNUSED:
793: break;
794: default:
795: fatal("Unknown socket type %d", sockets[i].type);
796: break;
797: }
1.46 markus 798: }
799:
800: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 801: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 802: if (*fdrp)
1.54 stevesk 803: xfree(*fdrp);
1.46 markus 804: if (*fdwp)
1.54 stevesk 805: xfree(*fdwp);
1.46 markus 806: *fdrp = xmalloc(sz);
807: *fdwp = xmalloc(sz);
1.66 markus 808: *nallocp = sz;
1.46 markus 809: }
1.66 markus 810: if (n < *fdl)
811: debug("XXX shrink: %d < %d", n, *fdl);
812: *fdl = n;
1.46 markus 813: memset(*fdrp, 0, sz);
814: memset(*fdwp, 0, sz);
815:
816: for (i = 0; i < sockets_alloc; i++) {
817: switch (sockets[i].type) {
818: case AUTH_SOCKET:
819: case AUTH_CONNECTION:
820: FD_SET(sockets[i].fd, *fdrp);
821: if (buffer_len(&sockets[i].output) > 0)
822: FD_SET(sockets[i].fd, *fdwp);
823: break;
824: default:
825: break;
826: }
827: }
828: return (1);
1.21 markus 829: }
830:
1.55 itojun 831: static void
1.21 markus 832: after_select(fd_set *readset, fd_set *writeset)
833: {
1.45 markus 834: u_int i;
1.21 markus 835: int len, sock;
1.26 markus 836: socklen_t slen;
1.21 markus 837: char buf[1024];
838: struct sockaddr_un sunaddr;
839:
840: for (i = 0; i < sockets_alloc; i++)
841: switch (sockets[i].type) {
842: case AUTH_UNUSED:
843: break;
844: case AUTH_SOCKET:
845: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 846: slen = sizeof(sunaddr);
1.46 markus 847: sock = accept(sockets[i].fd,
848: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 849: if (sock < 0) {
1.81 stevesk 850: error("accept from AUTH_SOCKET: %s",
851: strerror(errno));
1.21 markus 852: break;
853: }
854: new_socket(AUTH_CONNECTION, sock);
855: }
856: break;
857: case AUTH_CONNECTION:
858: if (buffer_len(&sockets[i].output) > 0 &&
859: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 860: do {
861: len = write(sockets[i].fd,
862: buffer_ptr(&sockets[i].output),
863: buffer_len(&sockets[i].output));
864: if (len == -1 && (errno == EAGAIN ||
865: errno == EINTR))
866: continue;
867: break;
868: } while (1);
1.21 markus 869: if (len <= 0) {
870: shutdown(sockets[i].fd, SHUT_RDWR);
871: close(sockets[i].fd);
872: sockets[i].type = AUTH_UNUSED;
1.30 djm 873: buffer_free(&sockets[i].input);
874: buffer_free(&sockets[i].output);
1.87 markus 875: buffer_free(&sockets[i].request);
1.21 markus 876: break;
877: }
878: buffer_consume(&sockets[i].output, len);
879: }
880: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 881: do {
882: len = read(sockets[i].fd, buf, sizeof(buf));
883: if (len == -1 && (errno == EAGAIN ||
884: errno == EINTR))
885: continue;
886: break;
887: } while (1);
1.21 markus 888: if (len <= 0) {
889: shutdown(sockets[i].fd, SHUT_RDWR);
890: close(sockets[i].fd);
891: sockets[i].type = AUTH_UNUSED;
1.30 djm 892: buffer_free(&sockets[i].input);
893: buffer_free(&sockets[i].output);
1.87 markus 894: buffer_free(&sockets[i].request);
1.21 markus 895: break;
896: }
897: buffer_append(&sockets[i].input, buf, len);
898: process_message(&sockets[i]);
899: }
900: break;
901: default:
902: fatal("Unknown type %d", sockets[i].type);
903: }
1.1 deraadt 904: }
905:
1.55 itojun 906: static void
1.81 stevesk 907: cleanup_socket(void *p)
1.15 markus 908: {
1.48 deraadt 909: if (socket_name[0])
910: unlink(socket_name);
911: if (socket_dir[0])
912: rmdir(socket_dir);
1.10 markus 913: }
914:
1.55 itojun 915: static void
1.15 markus 916: cleanup_exit(int i)
917: {
1.81 stevesk 918: cleanup_socket(NULL);
1.21 markus 919: exit(i);
1.15 markus 920: }
921:
1.55 itojun 922: static void
1.48 deraadt 923: cleanup_handler(int sig)
924: {
1.81 stevesk 925: cleanup_socket(NULL);
1.48 deraadt 926: _exit(2);
1.68 markus 927: }
928:
929: static void
930: check_parent_exists(int sig)
931: {
932: int save_errno = errno;
933:
934: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
935: /* printf("Parent has died - Authentication agent exiting.\n"); */
936: cleanup_handler(sig); /* safe */
937: }
938: signal(SIGALRM, check_parent_exists);
939: alarm(10);
940: errno = save_errno;
1.48 deraadt 941: }
942:
1.55 itojun 943: static void
1.50 itojun 944: usage(void)
1.15 markus 945: {
1.72 jakob 946: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 947: __progname);
1.72 jakob 948: fprintf(stderr, "Options:\n");
949: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
950: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
951: fprintf(stderr, " -k Kill the current agent.\n");
952: fprintf(stderr, " -d Debug mode.\n");
1.86 markus 953: fprintf(stderr, " -a socket Bind agent socket to given name.\n");
1.21 markus 954: exit(1);
1.15 markus 955: }
956:
1.2 provos 957: int
958: main(int ac, char **av)
1.1 deraadt 959: {
1.66 markus 960: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 961: struct sockaddr_un sunaddr;
1.41 markus 962: struct rlimit rlim;
1.21 markus 963: pid_t pid;
964: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.86 markus 965: char *agentsocket = NULL;
1.43 markus 966: extern int optind;
1.46 markus 967: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 968:
969: SSLeay_add_all_algorithms();
1.21 markus 970:
1.86 markus 971: while ((ch = getopt(ac, av, "cdksa:")) != -1) {
1.21 markus 972: switch (ch) {
973: case 'c':
974: if (s_flag)
975: usage();
976: c_flag++;
977: break;
978: case 'k':
979: k_flag++;
980: break;
981: case 's':
982: if (c_flag)
983: usage();
984: s_flag++;
985: break;
1.57 markus 986: case 'd':
987: if (d_flag)
988: usage();
989: d_flag++;
990: break;
1.86 markus 991: case 'a':
992: agentsocket = optarg;
993: break;
1.21 markus 994: default:
995: usage();
996: }
997: }
998: ac -= optind;
999: av += optind;
1000:
1.57 markus 1001: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 1002: usage();
1003:
1.85 markus 1004: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1005: shell = getenv("SHELL");
1006: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
1007: c_flag = 1;
1008: }
1009: if (k_flag) {
1010: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1011: if (pidstr == NULL) {
1012: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1013: SSH_AGENTPID_ENV_NAME);
1.21 markus 1014: exit(1);
1015: }
1016: pid = atoi(pidstr);
1.46 markus 1017: if (pid < 1) {
1.21 markus 1018: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 1019: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 1020: exit(1);
1021: }
1022: if (kill(pid, SIGTERM) == -1) {
1023: perror("kill");
1024: exit(1);
1025: }
1026: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1027: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1028: printf(format, SSH_AGENTPID_ENV_NAME);
1029: printf("echo Agent pid %d killed;\n", pid);
1030: exit(0);
1031: }
1032: parent_pid = getpid();
1033:
1.86 markus 1034: if (agentsocket == NULL) {
1035: /* Create private directory for agent socket */
1036: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
1037: if (mkdtemp(socket_dir) == NULL) {
1038: perror("mkdtemp: private socket dir");
1039: exit(1);
1040: }
1041: snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
1042: parent_pid);
1043: } else {
1044: /* Try to use specified agent socket */
1045: socket_dir[0] = '\0';
1046: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1047: }
1048:
1.23 markus 1049: /*
1050: * Create socket early so it will exist before command gets run from
1051: * the parent.
1052: */
1.21 markus 1053: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1054: if (sock < 0) {
1055: perror("socket");
1056: cleanup_exit(1);
1057: }
1058: memset(&sunaddr, 0, sizeof(sunaddr));
1059: sunaddr.sun_family = AF_UNIX;
1060: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
1061: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
1062: perror("bind");
1063: cleanup_exit(1);
1064: }
1065: if (listen(sock, 5) < 0) {
1066: perror("listen");
1067: cleanup_exit(1);
1068: }
1.46 markus 1069:
1.23 markus 1070: /*
1071: * Fork, and have the parent execute the command, if any, or present
1072: * the socket data. The child continues as the authentication agent.
1073: */
1.57 markus 1074: if (d_flag) {
1075: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
1076: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1077: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1078: SSH_AUTHSOCKET_ENV_NAME);
1079: printf("echo Agent pid %d;\n", parent_pid);
1080: goto skip;
1081: }
1.21 markus 1082: pid = fork();
1083: if (pid == -1) {
1084: perror("fork");
1.81 stevesk 1085: cleanup_exit(1);
1.21 markus 1086: }
1087: if (pid != 0) { /* Parent - execute the given command. */
1088: close(sock);
1089: snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
1090: if (ac == 0) {
1091: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1092: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1093: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1094: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1095: SSH_AGENTPID_ENV_NAME);
1.21 markus 1096: printf("echo Agent pid %d;\n", pid);
1097: exit(0);
1098: }
1.36 deraadt 1099: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1100: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1101: perror("setenv");
1102: exit(1);
1103: }
1.21 markus 1104: execvp(av[0], av);
1105: perror(av[0]);
1106: exit(1);
1107: }
1.81 stevesk 1108: /* child */
1109: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1110:
1111: if (setsid() == -1) {
1.81 stevesk 1112: error("setsid: %s", strerror(errno));
1.67 stevesk 1113: cleanup_exit(1);
1114: }
1115:
1116: (void)chdir("/");
1.21 markus 1117: close(0);
1118: close(1);
1119: close(2);
1120:
1.41 markus 1121: /* deny core dumps, since memory contains unencrypted private keys */
1122: rlim.rlim_cur = rlim.rlim_max = 0;
1123: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1124: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1125: cleanup_exit(1);
1126: }
1.57 markus 1127:
1128: skip:
1.81 stevesk 1129: fatal_add_cleanup(cleanup_socket, NULL);
1.21 markus 1130: new_socket(AUTH_SOCKET, sock);
1131: if (ac > 0) {
1132: signal(SIGALRM, check_parent_exists);
1133: alarm(10);
1134: }
1.33 markus 1135: idtab_init();
1.61 markus 1136: if (!d_flag)
1.57 markus 1137: signal(SIGINT, SIG_IGN);
1.61 markus 1138: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1139: signal(SIGHUP, cleanup_handler);
1140: signal(SIGTERM, cleanup_handler);
1.66 markus 1141: nalloc = 0;
1142:
1.21 markus 1143: while (1) {
1.66 markus 1144: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 1145: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 1146: if (errno == EINTR)
1147: continue;
1.81 stevesk 1148: fatal("select: %s", strerror(errno));
1.21 markus 1149: }
1.46 markus 1150: after_select(readsetp, writesetp);
1.15 markus 1151: }
1.21 markus 1152: /* NOTREACHED */
1.1 deraadt 1153: }
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