Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.54.2.3
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: *
1.54.2.1 jason 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"
1.54.2.2 miod 37: #include <sys/queue.h>
1.54.2.3! miod 38: RCSID("$OpenBSD: ssh-agent.c,v 1.85 2002/04/02 11:49:39 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:
1.54.2.1 jason 54: #ifdef SMARTCARD
55: #include "scard.h"
56: #endif
57:
1.54.2.2 miod 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;
1.54.2.2 miod 66: sock_type type;
1.21 markus 67: Buffer input;
68: Buffer output;
1.1 deraadt 69: } SocketEntry;
70:
1.45 markus 71: u_int sockets_alloc = 0;
1.1 deraadt 72: SocketEntry *sockets = NULL;
73:
1.54.2.2 miod 74: typedef struct identity {
75: TAILQ_ENTRY(identity) next;
1.33 markus 76: Key *key;
1.21 markus 77: char *comment;
1.1 deraadt 78: } Identity;
79:
1.33 markus 80: typedef struct {
81: int nentries;
1.54.2.2 miod 82: TAILQ_HEAD(idqueue, identity) idlist;
1.33 markus 83: } Idtab;
84:
85: /* private key table, one per protocol version */
86: Idtab idtable[3];
1.1 deraadt 87:
88: int max_fd = 0;
89:
1.11 markus 90: /* pid of shell == parent of agent */
1.29 deraadt 91: pid_t parent_pid = -1;
1.10 markus 92:
93: /* pathname and directory for AUTH_SOCKET */
94: char socket_name[1024];
95: char socket_dir[1024];
96:
1.20 markus 97: extern char *__progname;
98:
1.54.2.1 jason 99: static void
1.33 markus 100: idtab_init(void)
1.1 deraadt 101: {
1.33 markus 102: int i;
1.54.2.2 miod 103: for (i = 0; i <=2; i++) {
104: TAILQ_INIT(&idtable[i].idlist);
1.33 markus 105: idtable[i].nentries = 0;
106: }
107: }
108:
109: /* return private key table for requested protocol version */
1.54.2.1 jason 110: static Idtab *
1.33 markus 111: idtab_lookup(int version)
112: {
113: if (version < 1 || version > 2)
114: fatal("internal error, bad protocol version %d", version);
115: return &idtable[version];
116: }
117:
118: /* return matching private key for given public key */
1.54.2.2 miod 119: static Identity *
120: lookup_identity(Key *key, int version)
1.33 markus 121: {
1.54.2.2 miod 122: Identity *id;
123:
1.33 markus 124: Idtab *tab = idtab_lookup(version);
1.54.2.2 miod 125: TAILQ_FOREACH(id, &tab->idlist, next) {
126: if (key_equal(key, id->key))
127: return (id);
1.33 markus 128: }
1.54.2.2 miod 129: return (NULL);
130: }
131:
132: static void
133: free_identity(Identity *id)
134: {
135: key_free(id->key);
136: xfree(id->comment);
137: xfree(id);
1.33 markus 138: }
139:
140: /* send list of supported public keys to 'client' */
1.54.2.1 jason 141: static void
1.33 markus 142: process_request_identities(SocketEntry *e, int version)
143: {
144: Idtab *tab = idtab_lookup(version);
1.21 markus 145: Buffer msg;
1.54.2.2 miod 146: Identity *id;
1.1 deraadt 147:
1.21 markus 148: buffer_init(&msg);
1.33 markus 149: buffer_put_char(&msg, (version == 1) ?
150: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
151: buffer_put_int(&msg, tab->nentries);
1.54.2.2 miod 152: TAILQ_FOREACH(id, &tab->idlist, next) {
1.39 markus 153: if (id->key->type == KEY_RSA1) {
1.33 markus 154: buffer_put_int(&msg, BN_num_bits(id->key->rsa->n));
155: buffer_put_bignum(&msg, id->key->rsa->e);
156: buffer_put_bignum(&msg, id->key->rsa->n);
157: } else {
1.45 markus 158: u_char *blob;
159: u_int blen;
1.39 markus 160: key_to_blob(id->key, &blob, &blen);
1.33 markus 161: buffer_put_string(&msg, blob, blen);
162: xfree(blob);
163: }
164: buffer_put_cstring(&msg, id->comment);
1.21 markus 165: }
166: buffer_put_int(&e->output, buffer_len(&msg));
167: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
168: buffer_free(&msg);
1.1 deraadt 169: }
170:
1.33 markus 171: /* ssh1 only */
1.54.2.1 jason 172: static void
1.33 markus 173: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 174: {
1.54.2.2 miod 175: Identity *id;
176: Key *key;
1.33 markus 177: BIGNUM *challenge;
178: int i, len;
1.21 markus 179: Buffer msg;
180: MD5_CTX md;
1.45 markus 181: u_char buf[32], mdbuf[16], session_id[16];
182: u_int response_type;
1.21 markus 183:
184: buffer_init(&msg);
1.39 markus 185: key = key_new(KEY_RSA1);
1.54.2.2 miod 186: if ((challenge = BN_new()) == NULL)
187: fatal("process_authentication_challenge1: BN_new failed");
1.33 markus 188:
189: buffer_get_int(&e->input); /* ignored */
190: buffer_get_bignum(&e->input, key->rsa->e);
191: buffer_get_bignum(&e->input, key->rsa->n);
1.21 markus 192: buffer_get_bignum(&e->input, challenge);
193:
1.33 markus 194: /* Only protocol 1.1 is supported */
195: if (buffer_len(&e->input) == 0)
196: goto failure;
1.54.2.2 miod 197: buffer_get(&e->input, session_id, 16);
1.33 markus 198: response_type = buffer_get_int(&e->input);
199: if (response_type != 1)
200: goto failure;
201:
1.54.2.2 miod 202: id = lookup_identity(key, 1);
203: if (id != NULL) {
204: Key *private = id->key;
1.33 markus 205: /* Decrypt the challenge using the private key. */
1.49 markus 206: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
207: goto failure;
1.33 markus 208:
209: /* The response is MD5 of decrypted challenge plus session id. */
210: len = BN_num_bytes(challenge);
211: if (len <= 0 || len > 32) {
212: log("process_authentication_challenge: bad challenge length %d", len);
213: goto failure;
214: }
215: memset(buf, 0, 32);
216: BN_bn2bin(challenge, buf + 32 - len);
217: MD5_Init(&md);
218: MD5_Update(&md, buf, 32);
219: MD5_Update(&md, session_id, 16);
220: MD5_Final(mdbuf, &md);
221:
222: /* Send the response. */
223: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
224: for (i = 0; i < 16; i++)
225: buffer_put_char(&msg, mdbuf[i]);
226: goto send;
227: }
1.21 markus 228:
1.33 markus 229: failure:
230: /* Unknown identity or protocol error. Send failure. */
1.21 markus 231: buffer_put_char(&msg, SSH_AGENT_FAILURE);
232: send:
233: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 234: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
235: key_free(key);
236: BN_clear_free(challenge);
237: buffer_free(&msg);
238: }
239:
240: /* ssh2 only */
1.54.2.1 jason 241: static void
1.33 markus 242: process_sign_request2(SocketEntry *e)
243: {
244: extern int datafellows;
1.54.2.2 miod 245: Key *key;
1.45 markus 246: u_char *blob, *data, *signature = NULL;
247: u_int blen, dlen, slen = 0;
1.37 markus 248: int flags;
1.33 markus 249: Buffer msg;
250: int ok = -1;
251:
252: datafellows = 0;
1.43 markus 253:
1.33 markus 254: blob = buffer_get_string(&e->input, &blen);
255: data = buffer_get_string(&e->input, &dlen);
1.37 markus 256:
257: flags = buffer_get_int(&e->input);
258: if (flags & SSH_AGENT_OLD_SIGNATURE)
259: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 260:
1.39 markus 261: key = key_from_blob(blob, blen);
1.33 markus 262: if (key != NULL) {
1.54.2.2 miod 263: Identity *id = lookup_identity(key, 2);
264: if (id != NULL)
265: ok = key_sign(id->key, &signature, &slen, data, dlen);
1.33 markus 266: }
267: key_free(key);
268: buffer_init(&msg);
269: if (ok == 0) {
270: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
271: buffer_put_string(&msg, signature, slen);
272: } else {
273: buffer_put_char(&msg, SSH_AGENT_FAILURE);
274: }
275: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 276: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 277: buffer_len(&msg));
1.21 markus 278: buffer_free(&msg);
1.33 markus 279: xfree(data);
280: xfree(blob);
281: if (signature != NULL)
282: xfree(signature);
1.1 deraadt 283: }
284:
1.33 markus 285: /* shared */
1.54.2.1 jason 286: static void
1.33 markus 287: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 288: {
1.54.2.2 miod 289: Key *key = NULL;
1.45 markus 290: u_char *blob;
291: u_int blen;
292: u_int bits;
1.33 markus 293: int success = 0;
1.21 markus 294:
1.54.2.2 miod 295: switch (version) {
1.33 markus 296: case 1:
1.39 markus 297: key = key_new(KEY_RSA1);
1.33 markus 298: bits = buffer_get_int(&e->input);
299: buffer_get_bignum(&e->input, key->rsa->e);
300: buffer_get_bignum(&e->input, key->rsa->n);
301:
302: if (bits != key_size(key))
303: log("Warning: identity keysize mismatch: actual %d, announced %d",
1.46 markus 304: key_size(key), bits);
1.33 markus 305: break;
306: case 2:
307: blob = buffer_get_string(&e->input, &blen);
1.39 markus 308: key = key_from_blob(blob, blen);
1.33 markus 309: xfree(blob);
310: break;
311: }
312: if (key != NULL) {
1.54.2.2 miod 313: Identity *id = lookup_identity(key, version);
314: if (id != NULL) {
1.23 markus 315: /*
316: * We have this key. Free the old key. Since we
317: * don\'t want to leave empty slots in the middle of
1.40 markus 318: * the array, we actually free the key there and move
319: * all the entries between the empty slot and the end
320: * of the array.
1.23 markus 321: */
1.33 markus 322: Idtab *tab = idtab_lookup(version);
1.38 markus 323: if (tab->nentries < 1)
324: fatal("process_remove_identity: "
325: "internal error: tab->nentries %d",
326: tab->nentries);
1.54.2.2 miod 327: TAILQ_REMOVE(&tab->idlist, id, next);
328: free_identity(id);
1.33 markus 329: tab->nentries--;
330: success = 1;
1.21 markus 331: }
1.33 markus 332: key_free(key);
333: }
1.1 deraadt 334: buffer_put_int(&e->output, 1);
1.33 markus 335: buffer_put_char(&e->output,
336: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 337: }
338:
1.54.2.1 jason 339: static void
1.33 markus 340: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 341: {
1.33 markus 342: Idtab *tab = idtab_lookup(version);
1.54.2.2 miod 343: Identity *id;
1.21 markus 344:
345: /* Loop over all identities and clear the keys. */
1.54.2.2 miod 346: for (id = TAILQ_FIRST(&tab->idlist); id;
347: id = TAILQ_FIRST(&tab->idlist)) {
348: TAILQ_REMOVE(&tab->idlist, id, next);
349: free_identity(id);
1.21 markus 350: }
351:
352: /* Mark that there are no identities. */
1.33 markus 353: tab->nentries = 0;
1.21 markus 354:
355: /* Send success. */
356: buffer_put_int(&e->output, 1);
357: buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
358: return;
1.1 deraadt 359: }
360:
1.54.2.1 jason 361: static void
1.33 markus 362: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 363: {
1.33 markus 364: Key *k = NULL;
1.39 markus 365: char *type_name;
1.33 markus 366: char *comment;
1.39 markus 367: int type, success = 0;
1.33 markus 368: Idtab *tab = idtab_lookup(version);
369:
370: switch (version) {
371: case 1:
1.39 markus 372: k = key_new_private(KEY_RSA1);
1.46 markus 373: buffer_get_int(&e->input); /* ignored */
1.39 markus 374: buffer_get_bignum(&e->input, k->rsa->n);
375: buffer_get_bignum(&e->input, k->rsa->e);
376: buffer_get_bignum(&e->input, k->rsa->d);
377: buffer_get_bignum(&e->input, k->rsa->iqmp);
1.33 markus 378:
379: /* SSH and SSL have p and q swapped */
1.39 markus 380: buffer_get_bignum(&e->input, k->rsa->q); /* p */
381: buffer_get_bignum(&e->input, k->rsa->p); /* q */
1.33 markus 382:
383: /* Generate additional parameters */
1.54.2.1 jason 384: rsa_generate_additional_parameters(k->rsa);
1.33 markus 385: break;
386: case 2:
1.39 markus 387: type_name = buffer_get_string(&e->input, NULL);
1.46 markus 388: type = key_type_from_name(type_name);
1.39 markus 389: xfree(type_name);
1.54.2.2 miod 390: switch (type) {
1.39 markus 391: case KEY_DSA:
392: k = key_new_private(type);
393: buffer_get_bignum2(&e->input, k->dsa->p);
394: buffer_get_bignum2(&e->input, k->dsa->q);
395: buffer_get_bignum2(&e->input, k->dsa->g);
396: buffer_get_bignum2(&e->input, k->dsa->pub_key);
397: buffer_get_bignum2(&e->input, k->dsa->priv_key);
398: break;
399: case KEY_RSA:
400: k = key_new_private(type);
401: buffer_get_bignum2(&e->input, k->rsa->n);
402: buffer_get_bignum2(&e->input, k->rsa->e);
403: buffer_get_bignum2(&e->input, k->rsa->d);
404: buffer_get_bignum2(&e->input, k->rsa->iqmp);
405: buffer_get_bignum2(&e->input, k->rsa->p);
406: buffer_get_bignum2(&e->input, k->rsa->q);
407:
408: /* Generate additional parameters */
1.54.2.1 jason 409: rsa_generate_additional_parameters(k->rsa);
1.39 markus 410: break;
411: default:
1.33 markus 412: buffer_clear(&e->input);
413: goto send;
1.21 markus 414: }
1.33 markus 415: break;
416: }
417: comment = buffer_get_string(&e->input, NULL);
418: if (k == NULL) {
419: xfree(comment);
420: goto send;
421: }
422: success = 1;
1.54.2.2 miod 423: if (lookup_identity(k, version) == NULL) {
424: Identity *id = xmalloc(sizeof(Identity));
425: id->key = k;
426: id->comment = comment;
427: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
1.33 markus 428: /* Increment the number of identities. */
429: tab->nentries++;
430: } else {
431: key_free(k);
432: xfree(comment);
433: }
434: send:
1.1 deraadt 435: buffer_put_int(&e->output, 1);
1.33 markus 436: buffer_put_char(&e->output,
437: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 438: }
439:
1.54.2.1 jason 440:
441: #ifdef SMARTCARD
442: static void
443: process_add_smartcard_key (SocketEntry *e)
444: {
1.54.2.3! miod 445: Identity *id;
1.54.2.1 jason 446: Idtab *tab;
1.54.2.3! miod 447: Key **keys, *k;
! 448: char *sc_reader_id = NULL, *pin;
! 449: int i, version, success = 0;
1.54.2.2 miod 450:
1.54.2.1 jason 451: sc_reader_id = buffer_get_string(&e->input, NULL);
1.54.2.3! miod 452: pin = buffer_get_string(&e->input, NULL);
! 453: keys = sc_get_keys(sc_reader_id, pin);
1.54.2.1 jason 454: xfree(sc_reader_id);
1.54.2.3! miod 455: xfree(pin);
1.54.2.1 jason 456:
1.54.2.3! miod 457: if (keys == NULL || keys[0] == NULL) {
! 458: error("sc_get_keys failed");
1.54.2.1 jason 459: goto send;
460: }
1.54.2.3! miod 461: for (i = 0; keys[i] != NULL; i++) {
! 462: k = keys[i];
! 463: version = k->type == KEY_RSA1 ? 1 : 2;
! 464: tab = idtab_lookup(version);
! 465: if (lookup_identity(k, version) == NULL) {
! 466: id = xmalloc(sizeof(Identity));
! 467: id->key = k;
! 468: id->comment = xstrdup("smartcard key");
! 469: TAILQ_INSERT_TAIL(&tab->idlist, id, next);
! 470: tab->nentries++;
! 471: success = 1;
! 472: } else {
! 473: key_free(k);
! 474: }
! 475: keys[i] = NULL;
1.54.2.1 jason 476: }
1.54.2.3! miod 477: xfree(keys);
1.54.2.1 jason 478: send:
479: buffer_put_int(&e->output, 1);
480: buffer_put_char(&e->output,
481: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
482: }
483:
484: static void
485: process_remove_smartcard_key(SocketEntry *e)
486: {
1.54.2.3! miod 487: Identity *id;
! 488: Idtab *tab;
! 489: Key **keys, *k = NULL;
! 490: char *sc_reader_id = NULL, *pin;
! 491: int i, version, success = 0;
1.54.2.1 jason 492:
493: sc_reader_id = buffer_get_string(&e->input, NULL);
1.54.2.3! miod 494: pin = buffer_get_string(&e->input, NULL);
! 495: keys = sc_get_keys(sc_reader_id, pin);
1.54.2.1 jason 496: xfree(sc_reader_id);
1.54.2.3! miod 497: xfree(pin);
1.54.2.1 jason 498:
1.54.2.3! miod 499: if (keys == NULL || keys[0] == NULL) {
! 500: error("sc_get_keys failed");
! 501: goto send;
! 502: }
! 503: for (i = 0; keys[i] != NULL; i++) {
! 504: k = keys[i];
! 505: version = k->type == KEY_RSA1 ? 1 : 2;
! 506: if ((id = lookup_identity(k, version)) != NULL) {
! 507: tab = idtab_lookup(version);
! 508: TAILQ_REMOVE(&tab->idlist, id, next);
1.54.2.1 jason 509: tab->nentries--;
1.54.2.2 miod 510: free_identity(id);
1.54.2.1 jason 511: success = 1;
512: }
513: key_free(k);
1.54.2.3! miod 514: keys[i] = NULL;
1.54.2.1 jason 515: }
1.54.2.3! miod 516: xfree(keys);
! 517: send:
1.54.2.1 jason 518: buffer_put_int(&e->output, 1);
519: buffer_put_char(&e->output,
520: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
521: }
522: #endif /* SMARTCARD */
523:
1.33 markus 524: /* dispatch incoming messages */
525:
1.54.2.1 jason 526: static void
1.2 provos 527: process_message(SocketEntry *e)
1.1 deraadt 528: {
1.45 markus 529: u_int msg_len;
530: u_int type;
531: u_char *cp;
1.21 markus 532: if (buffer_len(&e->input) < 5)
533: return; /* Incomplete message. */
1.54.2.2 miod 534: cp = buffer_ptr(&e->input);
1.21 markus 535: msg_len = GET_32BIT(cp);
536: if (msg_len > 256 * 1024) {
537: shutdown(e->fd, SHUT_RDWR);
538: close(e->fd);
539: e->type = AUTH_UNUSED;
540: return;
541: }
542: if (buffer_len(&e->input) < msg_len + 4)
543: return;
544: buffer_consume(&e->input, 4);
545: type = buffer_get_char(&e->input);
546:
1.54.2.1 jason 547: debug("type %d", type);
1.21 markus 548: switch (type) {
1.33 markus 549: /* ssh1 */
550: case SSH_AGENTC_RSA_CHALLENGE:
551: process_authentication_challenge1(e);
552: break;
1.21 markus 553: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 554: process_request_identities(e, 1);
1.21 markus 555: break;
556: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 557: process_add_identity(e, 1);
1.21 markus 558: break;
559: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 560: process_remove_identity(e, 1);
1.21 markus 561: break;
562: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 563: process_remove_all_identities(e, 1);
564: break;
565: /* ssh2 */
566: case SSH2_AGENTC_SIGN_REQUEST:
567: process_sign_request2(e);
568: break;
569: case SSH2_AGENTC_REQUEST_IDENTITIES:
570: process_request_identities(e, 2);
571: break;
572: case SSH2_AGENTC_ADD_IDENTITY:
573: process_add_identity(e, 2);
574: break;
575: case SSH2_AGENTC_REMOVE_IDENTITY:
576: process_remove_identity(e, 2);
577: break;
578: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
579: process_remove_all_identities(e, 2);
1.21 markus 580: break;
1.54.2.1 jason 581: #ifdef SMARTCARD
582: case SSH_AGENTC_ADD_SMARTCARD_KEY:
583: process_add_smartcard_key(e);
1.54.2.2 miod 584: break;
1.54.2.1 jason 585: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
586: process_remove_smartcard_key(e);
1.54.2.2 miod 587: break;
1.54.2.1 jason 588: #endif /* SMARTCARD */
1.21 markus 589: default:
590: /* Unknown message. Respond with failure. */
591: error("Unknown message %d", type);
592: buffer_clear(&e->input);
593: buffer_put_int(&e->output, 1);
594: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
595: break;
596: }
1.1 deraadt 597: }
598:
1.54.2.1 jason 599: static void
1.54.2.2 miod 600: new_socket(sock_type type, int fd)
1.1 deraadt 601: {
1.45 markus 602: u_int i, old_alloc;
1.21 markus 603: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
604: error("fcntl O_NONBLOCK: %s", strerror(errno));
605:
606: if (fd > max_fd)
607: max_fd = fd;
608:
609: for (i = 0; i < sockets_alloc; i++)
610: if (sockets[i].type == AUTH_UNUSED) {
611: sockets[i].fd = fd;
612: sockets[i].type = type;
613: buffer_init(&sockets[i].input);
614: buffer_init(&sockets[i].output);
615: return;
616: }
617: old_alloc = sockets_alloc;
618: sockets_alloc += 10;
619: if (sockets)
620: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
621: else
622: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
623: for (i = old_alloc; i < sockets_alloc; i++)
624: sockets[i].type = AUTH_UNUSED;
625: sockets[old_alloc].type = type;
626: sockets[old_alloc].fd = fd;
627: buffer_init(&sockets[old_alloc].input);
628: buffer_init(&sockets[old_alloc].output);
1.1 deraadt 629: }
630:
1.54.2.1 jason 631: static int
632: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 633: {
1.46 markus 634: u_int i, sz;
635: int n = 0;
636:
637: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 638: switch (sockets[i].type) {
639: case AUTH_SOCKET:
640: case AUTH_CONNECTION:
1.46 markus 641: n = MAX(n, sockets[i].fd);
1.21 markus 642: break;
643: case AUTH_UNUSED:
644: break;
645: default:
646: fatal("Unknown socket type %d", sockets[i].type);
647: break;
648: }
1.46 markus 649: }
650:
651: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.54.2.1 jason 652: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 653: if (*fdrp)
1.54 stevesk 654: xfree(*fdrp);
1.46 markus 655: if (*fdwp)
1.54 stevesk 656: xfree(*fdwp);
1.46 markus 657: *fdrp = xmalloc(sz);
658: *fdwp = xmalloc(sz);
1.54.2.1 jason 659: *nallocp = sz;
1.46 markus 660: }
1.54.2.1 jason 661: if (n < *fdl)
662: debug("XXX shrink: %d < %d", n, *fdl);
663: *fdl = n;
1.46 markus 664: memset(*fdrp, 0, sz);
665: memset(*fdwp, 0, sz);
666:
667: for (i = 0; i < sockets_alloc; i++) {
668: switch (sockets[i].type) {
669: case AUTH_SOCKET:
670: case AUTH_CONNECTION:
671: FD_SET(sockets[i].fd, *fdrp);
672: if (buffer_len(&sockets[i].output) > 0)
673: FD_SET(sockets[i].fd, *fdwp);
674: break;
675: default:
676: break;
677: }
678: }
679: return (1);
1.21 markus 680: }
681:
1.54.2.1 jason 682: static void
1.21 markus 683: after_select(fd_set *readset, fd_set *writeset)
684: {
1.45 markus 685: u_int i;
1.21 markus 686: int len, sock;
1.26 markus 687: socklen_t slen;
1.21 markus 688: char buf[1024];
689: struct sockaddr_un sunaddr;
690:
691: for (i = 0; i < sockets_alloc; i++)
692: switch (sockets[i].type) {
693: case AUTH_UNUSED:
694: break;
695: case AUTH_SOCKET:
696: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 697: slen = sizeof(sunaddr);
1.46 markus 698: sock = accept(sockets[i].fd,
699: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 700: if (sock < 0) {
1.54.2.2 miod 701: error("accept from AUTH_SOCKET: %s",
702: strerror(errno));
1.21 markus 703: break;
704: }
705: new_socket(AUTH_CONNECTION, sock);
706: }
707: break;
708: case AUTH_CONNECTION:
709: if (buffer_len(&sockets[i].output) > 0 &&
710: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 711: do {
712: len = write(sockets[i].fd,
713: buffer_ptr(&sockets[i].output),
714: buffer_len(&sockets[i].output));
715: if (len == -1 && (errno == EAGAIN ||
716: errno == EINTR))
717: continue;
718: break;
719: } while (1);
1.21 markus 720: if (len <= 0) {
721: shutdown(sockets[i].fd, SHUT_RDWR);
722: close(sockets[i].fd);
723: sockets[i].type = AUTH_UNUSED;
1.30 djm 724: buffer_free(&sockets[i].input);
725: buffer_free(&sockets[i].output);
1.21 markus 726: break;
727: }
728: buffer_consume(&sockets[i].output, len);
729: }
730: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 731: do {
732: len = read(sockets[i].fd, buf, sizeof(buf));
733: if (len == -1 && (errno == EAGAIN ||
734: errno == EINTR))
735: continue;
736: break;
737: } while (1);
1.21 markus 738: if (len <= 0) {
739: shutdown(sockets[i].fd, SHUT_RDWR);
740: close(sockets[i].fd);
741: sockets[i].type = AUTH_UNUSED;
1.30 djm 742: buffer_free(&sockets[i].input);
743: buffer_free(&sockets[i].output);
1.21 markus 744: break;
745: }
746: buffer_append(&sockets[i].input, buf, len);
747: process_message(&sockets[i]);
748: }
749: break;
750: default:
751: fatal("Unknown type %d", sockets[i].type);
752: }
1.1 deraadt 753: }
754:
1.54.2.1 jason 755: static void
1.54.2.2 miod 756: cleanup_socket(void *p)
1.15 markus 757: {
1.48 deraadt 758: if (socket_name[0])
759: unlink(socket_name);
760: if (socket_dir[0])
761: rmdir(socket_dir);
1.10 markus 762: }
763:
1.54.2.1 jason 764: static void
1.15 markus 765: cleanup_exit(int i)
766: {
1.54.2.2 miod 767: cleanup_socket(NULL);
1.21 markus 768: exit(i);
1.15 markus 769: }
770:
1.54.2.1 jason 771: static void
1.48 deraadt 772: cleanup_handler(int sig)
773: {
1.54.2.2 miod 774: cleanup_socket(NULL);
1.48 deraadt 775: _exit(2);
776: }
777:
1.54.2.1 jason 778: static void
779: check_parent_exists(int sig)
780: {
781: int save_errno = errno;
782:
783: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
784: /* printf("Parent has died - Authentication agent exiting.\n"); */
785: cleanup_handler(sig); /* safe */
786: }
787: signal(SIGALRM, check_parent_exists);
788: alarm(10);
789: errno = save_errno;
790: }
791:
792: static void
1.50 itojun 793: usage(void)
1.15 markus 794: {
1.54.2.1 jason 795: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 796: __progname);
1.54.2.1 jason 797: fprintf(stderr, "Options:\n");
798: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
799: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
800: fprintf(stderr, " -k Kill the current agent.\n");
801: fprintf(stderr, " -d Debug mode.\n");
1.21 markus 802: exit(1);
1.15 markus 803: }
804:
1.2 provos 805: int
806: main(int ac, char **av)
1.1 deraadt 807: {
1.54.2.1 jason 808: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 809: struct sockaddr_un sunaddr;
1.41 markus 810: struct rlimit rlim;
1.21 markus 811: pid_t pid;
812: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.43 markus 813: extern int optind;
1.46 markus 814: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 815:
816: SSLeay_add_all_algorithms();
1.21 markus 817:
1.54.2.1 jason 818: while ((ch = getopt(ac, av, "cdks")) != -1) {
1.21 markus 819: switch (ch) {
820: case 'c':
821: if (s_flag)
822: usage();
823: c_flag++;
824: break;
825: case 'k':
826: k_flag++;
827: break;
828: case 's':
829: if (c_flag)
830: usage();
831: s_flag++;
832: break;
1.54.2.1 jason 833: case 'd':
834: if (d_flag)
835: usage();
836: d_flag++;
837: break;
1.21 markus 838: default:
839: usage();
840: }
841: }
842: ac -= optind;
843: av += optind;
844:
1.54.2.1 jason 845: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 846: usage();
847:
1.54.2.3! miod 848: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 849: shell = getenv("SHELL");
850: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
851: c_flag = 1;
852: }
853: if (k_flag) {
854: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
855: if (pidstr == NULL) {
856: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 857: SSH_AGENTPID_ENV_NAME);
1.21 markus 858: exit(1);
859: }
860: pid = atoi(pidstr);
1.46 markus 861: if (pid < 1) {
1.21 markus 862: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 863: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 864: exit(1);
865: }
866: if (kill(pid, SIGTERM) == -1) {
867: perror("kill");
868: exit(1);
869: }
870: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
871: printf(format, SSH_AUTHSOCKET_ENV_NAME);
872: printf(format, SSH_AGENTPID_ENV_NAME);
873: printf("echo Agent pid %d killed;\n", pid);
874: exit(0);
875: }
876: parent_pid = getpid();
877:
878: /* Create private directory for agent socket */
879: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
880: if (mkdtemp(socket_dir) == NULL) {
881: perror("mkdtemp: private socket dir");
882: exit(1);
883: }
884: snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
1.46 markus 885: parent_pid);
1.21 markus 886:
1.23 markus 887: /*
888: * Create socket early so it will exist before command gets run from
889: * the parent.
890: */
1.21 markus 891: sock = socket(AF_UNIX, SOCK_STREAM, 0);
892: if (sock < 0) {
893: perror("socket");
894: cleanup_exit(1);
895: }
896: memset(&sunaddr, 0, sizeof(sunaddr));
897: sunaddr.sun_family = AF_UNIX;
898: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
899: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
900: perror("bind");
901: cleanup_exit(1);
902: }
903: if (listen(sock, 5) < 0) {
904: perror("listen");
905: cleanup_exit(1);
906: }
1.46 markus 907:
1.23 markus 908: /*
909: * Fork, and have the parent execute the command, if any, or present
910: * the socket data. The child continues as the authentication agent.
911: */
1.54.2.1 jason 912: if (d_flag) {
913: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
914: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
915: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
916: SSH_AUTHSOCKET_ENV_NAME);
917: printf("echo Agent pid %d;\n", parent_pid);
918: goto skip;
919: }
1.21 markus 920: pid = fork();
921: if (pid == -1) {
922: perror("fork");
1.54.2.2 miod 923: cleanup_exit(1);
1.21 markus 924: }
925: if (pid != 0) { /* Parent - execute the given command. */
926: close(sock);
927: snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
928: if (ac == 0) {
929: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
930: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 931: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 932: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 933: SSH_AGENTPID_ENV_NAME);
1.21 markus 934: printf("echo Agent pid %d;\n", pid);
935: exit(0);
936: }
1.36 deraadt 937: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
938: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
939: perror("setenv");
940: exit(1);
941: }
1.21 markus 942: execvp(av[0], av);
943: perror(av[0]);
944: exit(1);
945: }
1.54.2.2 miod 946: /* child */
947: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.54.2.1 jason 948:
949: if (setsid() == -1) {
1.54.2.2 miod 950: error("setsid: %s", strerror(errno));
1.54.2.1 jason 951: cleanup_exit(1);
952: }
953:
954: (void)chdir("/");
1.21 markus 955: close(0);
956: close(1);
957: close(2);
958:
1.41 markus 959: /* deny core dumps, since memory contains unencrypted private keys */
960: rlim.rlim_cur = rlim.rlim_max = 0;
961: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
1.54.2.2 miod 962: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.41 markus 963: cleanup_exit(1);
964: }
1.54.2.1 jason 965:
966: skip:
1.54.2.2 miod 967: fatal_add_cleanup(cleanup_socket, NULL);
1.21 markus 968: new_socket(AUTH_SOCKET, sock);
969: if (ac > 0) {
970: signal(SIGALRM, check_parent_exists);
971: alarm(10);
972: }
1.33 markus 973: idtab_init();
1.54.2.1 jason 974: if (!d_flag)
975: signal(SIGINT, SIG_IGN);
1.21 markus 976: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 977: signal(SIGHUP, cleanup_handler);
978: signal(SIGTERM, cleanup_handler);
1.54.2.1 jason 979: nalloc = 0;
980:
1.21 markus 981: while (1) {
1.54.2.1 jason 982: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 983: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 984: if (errno == EINTR)
985: continue;
1.54.2.2 miod 986: fatal("select: %s", strerror(errno));
1.21 markus 987: }
1.46 markus 988: after_select(readsetp, writesetp);
1.15 markus 989: }
1.21 markus 990: /* NOTREACHED */
1.1 deraadt 991: }
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