Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.92
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>
1.92 ! markus 38: RCSID("$OpenBSD: ssh-agent.c,v 1.91 2002/06/11 05:46:20 mpech 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
1.92 ! markus 469: process_contrain_identity(SocketEntry *e, int version)
1.89 markus 470: {
471: Key *key = NULL;
472: u_char *blob;
1.92 ! markus 473: u_int blen, bits, death = 0;
1.89 markus 474: int success = 0;
475:
476: switch (version) {
477: case 1:
478: key = key_new(KEY_RSA1);
479: bits = buffer_get_int(&e->request);
480: buffer_get_bignum(&e->request, key->rsa->e);
481: buffer_get_bignum(&e->request, key->rsa->n);
482:
483: break;
484: case 2:
485: blob = buffer_get_string(&e->request, &blen);
486: key = key_from_blob(blob, blen);
487: xfree(blob);
488: break;
489: }
1.92 ! markus 490: while (buffer_len(&e->request)) {
! 491: switch (buffer_get_char(&e->request)) {
! 492: case SSH_AGENT_CONTRAIN_LIFETIME:
! 493: death = time(NULL) + buffer_get_int(&e->request);
! 494: break;
! 495: default:
! 496: break;
! 497: }
! 498: }
1.89 markus 499: if (key != NULL) {
500: Identity *id = lookup_identity(key, version);
1.92 ! markus 501: if (id != NULL && id->death == 0 && death != 0) {
1.89 markus 502: id->death = death;
503: success = 1;
504: }
505: key_free(key);
506: }
507: buffer_put_int(&e->output, 1);
508: buffer_put_char(&e->output,
509: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
510: }
511:
1.88 markus 512: /* XXX todo: encrypt sensitive data with passphrase */
513: static void
514: process_lock_agent(SocketEntry *e, int lock)
515: {
516: char *passwd;
517: int success = 0;
518:
519: passwd = buffer_get_string(&e->request, NULL);
520: if (locked && !lock && strcmp(passwd, lock_passwd) == 0) {
521: locked = 0;
522: memset(lock_passwd, 0, strlen(lock_passwd));
523: xfree(lock_passwd);
524: lock_passwd = NULL;
525: success = 1;
526: } else if (!locked && lock) {
527: locked = 1;
528: lock_passwd = xstrdup(passwd);
529: success = 1;
530: }
531: memset(passwd, 0, strlen(passwd));
532: xfree(passwd);
533:
534: buffer_put_int(&e->output, 1);
535: buffer_put_char(&e->output,
536: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
537: return;
538: }
539:
540: static void
541: no_identities(SocketEntry *e, u_int type)
542: {
543: Buffer msg;
544:
545: buffer_init(&msg);
546: buffer_put_char(&msg,
547: (type == SSH_AGENTC_REQUEST_RSA_IDENTITIES) ?
548: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
549: buffer_put_int(&msg, 0);
550: buffer_put_int(&e->output, buffer_len(&msg));
551: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
552: buffer_free(&msg);
553: }
1.59 markus 554:
555: #ifdef SMARTCARD
556: static void
557: process_add_smartcard_key (SocketEntry *e)
558: {
1.84 markus 559: Identity *id;
1.59 markus 560: Idtab *tab;
1.84 markus 561: Key **keys, *k;
1.83 rees 562: char *sc_reader_id = NULL, *pin;
1.84 markus 563: int i, version, success = 0;
1.75 deraadt 564:
1.87 markus 565: sc_reader_id = buffer_get_string(&e->request, NULL);
566: pin = buffer_get_string(&e->request, NULL);
1.84 markus 567: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 568: xfree(sc_reader_id);
1.83 rees 569: xfree(pin);
1.59 markus 570:
1.84 markus 571: if (keys == NULL || keys[0] == NULL) {
572: error("sc_get_keys failed");
1.59 markus 573: goto send;
574: }
1.84 markus 575: for (i = 0; keys[i] != NULL; i++) {
576: k = keys[i];
577: version = k->type == KEY_RSA1 ? 1 : 2;
578: tab = idtab_lookup(version);
579: if (lookup_identity(k, version) == NULL) {
580: id = xmalloc(sizeof(Identity));
581: id->key = k;
582: id->comment = xstrdup("smartcard key");
1.89 markus 583: id->death = 0;
1.84 markus 584: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
585: tab->nentries++;
586: success = 1;
587: } else {
588: key_free(k);
589: }
590: keys[i] = NULL;
1.59 markus 591: }
1.84 markus 592: xfree(keys);
1.59 markus 593: send:
594: buffer_put_int(&e->output, 1);
595: buffer_put_char(&e->output,
596: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
597: }
598:
599: static void
600: process_remove_smartcard_key(SocketEntry *e)
601: {
1.84 markus 602: Identity *id;
603: Idtab *tab;
604: Key **keys, *k = NULL;
1.83 rees 605: char *sc_reader_id = NULL, *pin;
1.84 markus 606: int i, version, success = 0;
1.59 markus 607:
1.87 markus 608: sc_reader_id = buffer_get_string(&e->request, NULL);
609: pin = buffer_get_string(&e->request, NULL);
1.84 markus 610: keys = sc_get_keys(sc_reader_id, pin);
1.69 markus 611: xfree(sc_reader_id);
1.83 rees 612: xfree(pin);
1.59 markus 613:
1.84 markus 614: if (keys == NULL || keys[0] == NULL) {
615: error("sc_get_keys failed");
616: goto send;
617: }
618: for (i = 0; keys[i] != NULL; i++) {
619: k = keys[i];
620: version = k->type == KEY_RSA1 ? 1 : 2;
621: if ((id = lookup_identity(k, version)) != NULL) {
622: tab = idtab_lookup(version);
1.90 markus 623: TAILQ_REMOVE(&tab->idlist, id, next);
1.59 markus 624: tab->nentries--;
1.78 provos 625: free_identity(id);
1.59 markus 626: success = 1;
627: }
628: key_free(k);
1.84 markus 629: keys[i] = NULL;
1.59 markus 630: }
1.84 markus 631: xfree(keys);
632: send:
1.59 markus 633: buffer_put_int(&e->output, 1);
634: buffer_put_char(&e->output,
635: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
636: }
1.70 jakob 637: #endif /* SMARTCARD */
1.59 markus 638:
1.33 markus 639: /* dispatch incoming messages */
640:
1.55 itojun 641: static void
1.2 provos 642: process_message(SocketEntry *e)
1.1 deraadt 643: {
1.45 markus 644: u_int msg_len;
645: u_int type;
646: u_char *cp;
1.89 markus 647:
648: /* kill dead keys */
649: reaper();
650:
1.21 markus 651: if (buffer_len(&e->input) < 5)
652: return; /* Incomplete message. */
1.77 stevesk 653: cp = buffer_ptr(&e->input);
1.21 markus 654: msg_len = GET_32BIT(cp);
655: if (msg_len > 256 * 1024) {
656: shutdown(e->fd, SHUT_RDWR);
657: close(e->fd);
658: e->type = AUTH_UNUSED;
1.87 markus 659: buffer_free(&e->input);
660: buffer_free(&e->output);
661: buffer_free(&e->request);
1.21 markus 662: return;
663: }
664: if (buffer_len(&e->input) < msg_len + 4)
665: return;
1.87 markus 666:
667: /* move the current input to e->request */
1.21 markus 668: buffer_consume(&e->input, 4);
1.87 markus 669: buffer_clear(&e->request);
670: buffer_append(&e->request, buffer_ptr(&e->input), msg_len);
671: buffer_consume(&e->input, msg_len);
672: type = buffer_get_char(&e->request);
1.21 markus 673:
1.88 markus 674: /* check wheter agent is locked */
675: if (locked && type != SSH_AGENTC_UNLOCK) {
676: buffer_clear(&e->request);
677: switch (type) {
678: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
679: case SSH2_AGENTC_REQUEST_IDENTITIES:
680: /* send empty lists */
681: no_identities(e, type);
682: break;
683: default:
684: /* send a fail message for all other request types */
685: buffer_put_int(&e->output, 1);
686: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
687: }
688: return;
689: }
690:
1.59 markus 691: debug("type %d", type);
1.21 markus 692: switch (type) {
1.88 markus 693: case SSH_AGENTC_LOCK:
694: case SSH_AGENTC_UNLOCK:
695: process_lock_agent(e, type == SSH_AGENTC_LOCK);
696: break;
1.33 markus 697: /* ssh1 */
698: case SSH_AGENTC_RSA_CHALLENGE:
699: process_authentication_challenge1(e);
700: break;
1.21 markus 701: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 702: process_request_identities(e, 1);
1.21 markus 703: break;
704: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 705: process_add_identity(e, 1);
1.21 markus 706: break;
707: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 708: process_remove_identity(e, 1);
1.21 markus 709: break;
710: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 711: process_remove_all_identities(e, 1);
712: break;
1.92 ! markus 713: case SSH_AGENTC_CONTRAIN_IDENTITY1:
! 714: process_contrain_identity(e, 1);
1.89 markus 715: break;
1.33 markus 716: /* ssh2 */
717: case SSH2_AGENTC_SIGN_REQUEST:
718: process_sign_request2(e);
719: break;
720: case SSH2_AGENTC_REQUEST_IDENTITIES:
721: process_request_identities(e, 2);
722: break;
723: case SSH2_AGENTC_ADD_IDENTITY:
724: process_add_identity(e, 2);
725: break;
726: case SSH2_AGENTC_REMOVE_IDENTITY:
727: process_remove_identity(e, 2);
728: break;
729: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
730: process_remove_all_identities(e, 2);
1.89 markus 731: break;
1.92 ! markus 732: case SSH_AGENTC_CONTRAIN_IDENTITY:
! 733: process_contrain_identity(e, 2);
1.21 markus 734: break;
1.59 markus 735: #ifdef SMARTCARD
736: case SSH_AGENTC_ADD_SMARTCARD_KEY:
737: process_add_smartcard_key(e);
1.75 deraadt 738: break;
1.59 markus 739: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
740: process_remove_smartcard_key(e);
1.75 deraadt 741: break;
1.70 jakob 742: #endif /* SMARTCARD */
1.21 markus 743: default:
744: /* Unknown message. Respond with failure. */
745: error("Unknown message %d", type);
1.87 markus 746: buffer_clear(&e->request);
1.21 markus 747: buffer_put_int(&e->output, 1);
748: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
749: break;
750: }
1.1 deraadt 751: }
752:
1.55 itojun 753: static void
1.73 stevesk 754: new_socket(sock_type type, int fd)
1.1 deraadt 755: {
1.45 markus 756: u_int i, old_alloc;
1.21 markus 757: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
758: error("fcntl O_NONBLOCK: %s", strerror(errno));
759:
760: if (fd > max_fd)
761: max_fd = fd;
762:
763: for (i = 0; i < sockets_alloc; i++)
764: if (sockets[i].type == AUTH_UNUSED) {
765: sockets[i].fd = fd;
766: sockets[i].type = type;
767: buffer_init(&sockets[i].input);
768: buffer_init(&sockets[i].output);
1.87 markus 769: buffer_init(&sockets[i].request);
1.21 markus 770: return;
771: }
772: old_alloc = sockets_alloc;
773: sockets_alloc += 10;
774: if (sockets)
775: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
776: else
777: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
778: for (i = old_alloc; i < sockets_alloc; i++)
779: sockets[i].type = AUTH_UNUSED;
780: sockets[old_alloc].type = type;
781: sockets[old_alloc].fd = fd;
782: buffer_init(&sockets[old_alloc].input);
783: buffer_init(&sockets[old_alloc].output);
1.87 markus 784: buffer_init(&sockets[old_alloc].request);
1.1 deraadt 785: }
786:
1.55 itojun 787: static int
1.66 markus 788: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 789: {
1.46 markus 790: u_int i, sz;
791: int n = 0;
792:
793: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 794: switch (sockets[i].type) {
795: case AUTH_SOCKET:
796: case AUTH_CONNECTION:
1.46 markus 797: n = MAX(n, sockets[i].fd);
1.21 markus 798: break;
799: case AUTH_UNUSED:
800: break;
801: default:
802: fatal("Unknown socket type %d", sockets[i].type);
803: break;
804: }
1.46 markus 805: }
806:
807: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 808: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 809: if (*fdrp)
1.54 stevesk 810: xfree(*fdrp);
1.46 markus 811: if (*fdwp)
1.54 stevesk 812: xfree(*fdwp);
1.46 markus 813: *fdrp = xmalloc(sz);
814: *fdwp = xmalloc(sz);
1.66 markus 815: *nallocp = sz;
1.46 markus 816: }
1.66 markus 817: if (n < *fdl)
818: debug("XXX shrink: %d < %d", n, *fdl);
819: *fdl = n;
1.46 markus 820: memset(*fdrp, 0, sz);
821: memset(*fdwp, 0, sz);
822:
823: for (i = 0; i < sockets_alloc; i++) {
824: switch (sockets[i].type) {
825: case AUTH_SOCKET:
826: case AUTH_CONNECTION:
827: FD_SET(sockets[i].fd, *fdrp);
828: if (buffer_len(&sockets[i].output) > 0)
829: FD_SET(sockets[i].fd, *fdwp);
830: break;
831: default:
832: break;
833: }
834: }
835: return (1);
1.21 markus 836: }
837:
1.55 itojun 838: static void
1.21 markus 839: after_select(fd_set *readset, fd_set *writeset)
840: {
1.45 markus 841: u_int i;
1.21 markus 842: int len, sock;
1.26 markus 843: socklen_t slen;
1.21 markus 844: char buf[1024];
845: struct sockaddr_un sunaddr;
846:
847: for (i = 0; i < sockets_alloc; i++)
848: switch (sockets[i].type) {
849: case AUTH_UNUSED:
850: break;
851: case AUTH_SOCKET:
852: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 853: slen = sizeof(sunaddr);
1.46 markus 854: sock = accept(sockets[i].fd,
855: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 856: if (sock < 0) {
1.81 stevesk 857: error("accept from AUTH_SOCKET: %s",
858: strerror(errno));
1.21 markus 859: break;
860: }
861: new_socket(AUTH_CONNECTION, sock);
862: }
863: break;
864: case AUTH_CONNECTION:
865: if (buffer_len(&sockets[i].output) > 0 &&
866: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 867: do {
868: len = write(sockets[i].fd,
869: buffer_ptr(&sockets[i].output),
870: buffer_len(&sockets[i].output));
871: if (len == -1 && (errno == EAGAIN ||
872: errno == EINTR))
873: continue;
874: break;
875: } while (1);
1.21 markus 876: if (len <= 0) {
877: shutdown(sockets[i].fd, SHUT_RDWR);
878: close(sockets[i].fd);
879: sockets[i].type = AUTH_UNUSED;
1.30 djm 880: buffer_free(&sockets[i].input);
881: buffer_free(&sockets[i].output);
1.87 markus 882: buffer_free(&sockets[i].request);
1.21 markus 883: break;
884: }
885: buffer_consume(&sockets[i].output, len);
886: }
887: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 888: do {
889: len = read(sockets[i].fd, buf, sizeof(buf));
890: if (len == -1 && (errno == EAGAIN ||
891: errno == EINTR))
892: continue;
893: break;
894: } while (1);
1.21 markus 895: if (len <= 0) {
896: shutdown(sockets[i].fd, SHUT_RDWR);
897: close(sockets[i].fd);
898: sockets[i].type = AUTH_UNUSED;
1.30 djm 899: buffer_free(&sockets[i].input);
900: buffer_free(&sockets[i].output);
1.87 markus 901: buffer_free(&sockets[i].request);
1.21 markus 902: break;
903: }
904: buffer_append(&sockets[i].input, buf, len);
905: process_message(&sockets[i]);
906: }
907: break;
908: default:
909: fatal("Unknown type %d", sockets[i].type);
910: }
1.1 deraadt 911: }
912:
1.55 itojun 913: static void
1.81 stevesk 914: cleanup_socket(void *p)
1.15 markus 915: {
1.48 deraadt 916: if (socket_name[0])
917: unlink(socket_name);
918: if (socket_dir[0])
919: rmdir(socket_dir);
1.10 markus 920: }
921:
1.55 itojun 922: static void
1.15 markus 923: cleanup_exit(int i)
924: {
1.81 stevesk 925: cleanup_socket(NULL);
1.21 markus 926: exit(i);
1.15 markus 927: }
928:
1.55 itojun 929: static void
1.48 deraadt 930: cleanup_handler(int sig)
931: {
1.81 stevesk 932: cleanup_socket(NULL);
1.48 deraadt 933: _exit(2);
1.68 markus 934: }
935:
936: static void
937: check_parent_exists(int sig)
938: {
939: int save_errno = errno;
940:
941: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
942: /* printf("Parent has died - Authentication agent exiting.\n"); */
943: cleanup_handler(sig); /* safe */
944: }
945: signal(SIGALRM, check_parent_exists);
946: alarm(10);
947: errno = save_errno;
1.48 deraadt 948: }
949:
1.55 itojun 950: static void
1.50 itojun 951: usage(void)
1.15 markus 952: {
1.72 jakob 953: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 954: __progname);
1.72 jakob 955: fprintf(stderr, "Options:\n");
956: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
957: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
958: fprintf(stderr, " -k Kill the current agent.\n");
959: fprintf(stderr, " -d Debug mode.\n");
1.86 markus 960: fprintf(stderr, " -a socket Bind agent socket to given name.\n");
1.21 markus 961: exit(1);
1.15 markus 962: }
963:
1.2 provos 964: int
965: main(int ac, char **av)
1.1 deraadt 966: {
1.66 markus 967: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 968: struct sockaddr_un sunaddr;
1.41 markus 969: struct rlimit rlim;
1.21 markus 970: pid_t pid;
971: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.86 markus 972: char *agentsocket = NULL;
1.43 markus 973: extern int optind;
1.46 markus 974: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 975:
976: SSLeay_add_all_algorithms();
1.21 markus 977:
1.86 markus 978: while ((ch = getopt(ac, av, "cdksa:")) != -1) {
1.21 markus 979: switch (ch) {
980: case 'c':
981: if (s_flag)
982: usage();
983: c_flag++;
984: break;
985: case 'k':
986: k_flag++;
987: break;
988: case 's':
989: if (c_flag)
990: usage();
991: s_flag++;
992: break;
1.57 markus 993: case 'd':
994: if (d_flag)
995: usage();
996: d_flag++;
997: break;
1.86 markus 998: case 'a':
999: agentsocket = optarg;
1000: break;
1.21 markus 1001: default:
1002: usage();
1003: }
1004: }
1005: ac -= optind;
1006: av += optind;
1007:
1.57 markus 1008: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 1009: usage();
1010:
1.85 markus 1011: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 1012: shell = getenv("SHELL");
1013: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
1014: c_flag = 1;
1015: }
1016: if (k_flag) {
1017: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
1018: if (pidstr == NULL) {
1019: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 1020: SSH_AGENTPID_ENV_NAME);
1.21 markus 1021: exit(1);
1022: }
1023: pid = atoi(pidstr);
1.46 markus 1024: if (pid < 1) {
1.21 markus 1025: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 1026: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 1027: exit(1);
1028: }
1029: if (kill(pid, SIGTERM) == -1) {
1030: perror("kill");
1031: exit(1);
1032: }
1033: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1034: printf(format, SSH_AUTHSOCKET_ENV_NAME);
1035: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 1036: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 1037: exit(0);
1038: }
1039: parent_pid = getpid();
1040:
1.86 markus 1041: if (agentsocket == NULL) {
1042: /* Create private directory for agent socket */
1043: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
1044: if (mkdtemp(socket_dir) == NULL) {
1045: perror("mkdtemp: private socket dir");
1046: exit(1);
1047: }
1.91 mpech 1048: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
1049: (long)parent_pid);
1.86 markus 1050: } else {
1051: /* Try to use specified agent socket */
1052: socket_dir[0] = '\0';
1053: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 1054: }
1055:
1.23 markus 1056: /*
1057: * Create socket early so it will exist before command gets run from
1058: * the parent.
1059: */
1.21 markus 1060: sock = socket(AF_UNIX, SOCK_STREAM, 0);
1061: if (sock < 0) {
1062: perror("socket");
1063: cleanup_exit(1);
1064: }
1065: memset(&sunaddr, 0, sizeof(sunaddr));
1066: sunaddr.sun_family = AF_UNIX;
1067: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
1068: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
1069: perror("bind");
1070: cleanup_exit(1);
1071: }
1072: if (listen(sock, 5) < 0) {
1073: perror("listen");
1074: cleanup_exit(1);
1075: }
1.46 markus 1076:
1.23 markus 1077: /*
1078: * Fork, and have the parent execute the command, if any, or present
1079: * the socket data. The child continues as the authentication agent.
1080: */
1.57 markus 1081: if (d_flag) {
1082: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
1083: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1084: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1085: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 1086: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.57 markus 1087: goto skip;
1088: }
1.21 markus 1089: pid = fork();
1090: if (pid == -1) {
1091: perror("fork");
1.81 stevesk 1092: cleanup_exit(1);
1.21 markus 1093: }
1094: if (pid != 0) { /* Parent - execute the given command. */
1095: close(sock);
1.91 mpech 1096: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 1097: if (ac == 0) {
1098: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
1099: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 1100: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 1101: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 1102: SSH_AGENTPID_ENV_NAME);
1.91 mpech 1103: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 1104: exit(0);
1105: }
1.36 deraadt 1106: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
1107: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
1108: perror("setenv");
1109: exit(1);
1110: }
1.21 markus 1111: execvp(av[0], av);
1112: perror(av[0]);
1113: exit(1);
1114: }
1.81 stevesk 1115: /* child */
1116: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 1117:
1118: if (setsid() == -1) {
1.81 stevesk 1119: error("setsid: %s", strerror(errno));
1.67 stevesk 1120: cleanup_exit(1);
1121: }
1122:
1123: (void)chdir("/");
1.21 markus 1124: close(0);
1125: close(1);
1126: close(2);
1127:
1.41 markus 1128: /* deny core dumps, since memory contains unencrypted private keys */
1129: rlim.rlim_cur = rlim.rlim_max = 0;
1130: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.81 stevesk 1131: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 1132: cleanup_exit(1);
1133: }
1.57 markus 1134:
1135: skip:
1.81 stevesk 1136: fatal_add_cleanup(cleanup_socket, NULL);
1.21 markus 1137: new_socket(AUTH_SOCKET, sock);
1138: if (ac > 0) {
1139: signal(SIGALRM, check_parent_exists);
1140: alarm(10);
1141: }
1.33 markus 1142: idtab_init();
1.61 markus 1143: if (!d_flag)
1.57 markus 1144: signal(SIGINT, SIG_IGN);
1.61 markus 1145: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1146: signal(SIGHUP, cleanup_handler);
1147: signal(SIGTERM, cleanup_handler);
1.66 markus 1148: nalloc = 0;
1149:
1.21 markus 1150: while (1) {
1.66 markus 1151: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 1152: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 1153: if (errno == EINTR)
1154: continue;
1.81 stevesk 1155: fatal("select: %s", strerror(errno));
1.21 markus 1156: }
1.46 markus 1157: after_select(readsetp, writesetp);
1.15 markus 1158: }
1.21 markus 1159: /* NOTREACHED */
1.1 deraadt 1160: }
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