Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.77
1.77 ! stevesk 1: /* $OpenBSD: ssh-agent.c,v 1.76 2001/12/27 18:22:16 markus Exp $ */
1.15 markus 2:
1.1 deraadt 3: /*
1.22 deraadt 4: * Author: Tatu Ylonen <ylo@cs.hut.fi>
5: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6: * All rights reserved
7: * The authentication agent program.
1.33 markus 8: *
1.35 deraadt 9: * As far as I am concerned, the code I have written for this software
10: * can be used freely for any purpose. Any derived versions of this
11: * software must be clearly marked as such, and if the derived work is
12: * incompatible with the protocol description in the RFC file, it must be
13: * called by a name other than "ssh" or "Secure Shell".
14: *
1.56 markus 15: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.35 deraadt 16: *
17: * Redistribution and use in source and binary forms, with or without
18: * modification, are permitted provided that the following conditions
19: * are met:
20: * 1. Redistributions of source code must retain the above copyright
21: * notice, this list of conditions and the following disclaimer.
22: * 2. Redistributions in binary form must reproduce the above copyright
23: * notice, this list of conditions and the following disclaimer in the
24: * documentation and/or other materials provided with the distribution.
25: *
26: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.22 deraadt 36: */
1.1 deraadt 37:
38: #include "includes.h"
1.77 ! stevesk 39: RCSID("$OpenBSD: ssh-agent.c,v 1.76 2001/12/27 18:22:16 markus Exp $");
1.47 markus 40:
41: #include <openssl/evp.h>
42: #include <openssl/md5.h>
1.1 deraadt 43:
44: #include "ssh.h"
45: #include "rsa.h"
46: #include "buffer.h"
47: #include "bufaux.h"
48: #include "xmalloc.h"
49: #include "packet.h"
50: #include "getput.h"
51: #include "mpaux.h"
1.32 markus 52: #include "key.h"
53: #include "authfd.h"
1.47 markus 54: #include "cipher.h"
1.33 markus 55: #include "kex.h"
1.37 markus 56: #include "compat.h"
1.47 markus 57: #include "log.h"
1.7 deraadt 58:
1.59 markus 59: #ifdef SMARTCARD
60: #include <openssl/engine.h>
61: #include "scard.h"
1.71 jakob 62: #endif
1.59 markus 63:
1.73 stevesk 64: typedef enum {
65: AUTH_UNUSED,
66: AUTH_SOCKET,
67: AUTH_CONNECTION
68: } sock_type;
69:
1.21 markus 70: typedef struct {
71: int fd;
1.73 stevesk 72: sock_type type;
1.21 markus 73: Buffer input;
74: Buffer output;
1.1 deraadt 75: } SocketEntry;
76:
1.45 markus 77: u_int sockets_alloc = 0;
1.1 deraadt 78: SocketEntry *sockets = NULL;
79:
1.21 markus 80: typedef struct {
1.33 markus 81: Key *key;
1.21 markus 82: char *comment;
1.1 deraadt 83: } Identity;
84:
1.33 markus 85: typedef struct {
86: int nentries;
87: Identity *identities;
88: } Idtab;
89:
90: /* private key table, one per protocol version */
91: Idtab idtable[3];
1.1 deraadt 92:
93: int max_fd = 0;
94:
1.11 markus 95: /* pid of shell == parent of agent */
1.29 deraadt 96: pid_t parent_pid = -1;
1.10 markus 97:
98: /* pathname and directory for AUTH_SOCKET */
99: char socket_name[1024];
100: char socket_dir[1024];
101:
1.20 markus 102: extern char *__progname;
103:
1.55 itojun 104: static void
1.33 markus 105: idtab_init(void)
1.1 deraadt 106: {
1.33 markus 107: int i;
1.74 deraadt 108: for (i = 0; i <=2; i++) {
1.33 markus 109: idtable[i].identities = NULL;
110: idtable[i].nentries = 0;
111: }
112: }
113:
114: /* return private key table for requested protocol version */
1.55 itojun 115: static Idtab *
1.33 markus 116: idtab_lookup(int version)
117: {
118: if (version < 1 || version > 2)
119: fatal("internal error, bad protocol version %d", version);
120: return &idtable[version];
121: }
122:
123: /* return matching private key for given public key */
1.55 itojun 124: static Key *
1.33 markus 125: lookup_private_key(Key *key, int *idx, int version)
126: {
127: int i;
128: Idtab *tab = idtab_lookup(version);
129: for (i = 0; i < tab->nentries; i++) {
130: if (key_equal(key, tab->identities[i].key)) {
131: if (idx != NULL)
132: *idx = i;
133: return tab->identities[i].key;
134: }
135: }
136: return NULL;
137: }
138:
139: /* send list of supported public keys to 'client' */
1.55 itojun 140: static void
1.33 markus 141: process_request_identities(SocketEntry *e, int version)
142: {
143: Idtab *tab = idtab_lookup(version);
1.21 markus 144: Buffer msg;
145: int i;
1.1 deraadt 146:
1.21 markus 147: buffer_init(&msg);
1.33 markus 148: buffer_put_char(&msg, (version == 1) ?
149: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
150: buffer_put_int(&msg, tab->nentries);
151: for (i = 0; i < tab->nentries; i++) {
152: Identity *id = &tab->identities[i];
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 */
1.55 itojun 172: static void
1.33 markus 173: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 174: {
1.33 markus 175: Key *key, *private;
176: BIGNUM *challenge;
177: int i, len;
1.21 markus 178: Buffer msg;
179: MD5_CTX md;
1.45 markus 180: u_char buf[32], mdbuf[16], session_id[16];
181: u_int response_type;
1.21 markus 182:
183: buffer_init(&msg);
1.39 markus 184: key = key_new(KEY_RSA1);
1.76 markus 185: if ((challenge = BN_new()) == NULL)
186: fatal("process_authentication_challenge1: BN_new failed");
1.33 markus 187:
188: buffer_get_int(&e->input); /* ignored */
189: buffer_get_bignum(&e->input, key->rsa->e);
190: buffer_get_bignum(&e->input, key->rsa->n);
1.21 markus 191: buffer_get_bignum(&e->input, challenge);
192:
1.33 markus 193: /* Only protocol 1.1 is supported */
194: if (buffer_len(&e->input) == 0)
195: goto failure;
196: buffer_get(&e->input, (char *) session_id, 16);
197: response_type = buffer_get_int(&e->input);
198: if (response_type != 1)
199: goto failure;
200:
201: private = lookup_private_key(key, NULL, 1);
202: if (private != NULL) {
203: /* Decrypt the challenge using the private key. */
1.49 markus 204: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
205: goto failure;
1.33 markus 206:
207: /* The response is MD5 of decrypted challenge plus session id. */
208: len = BN_num_bytes(challenge);
209: if (len <= 0 || len > 32) {
210: log("process_authentication_challenge: bad challenge length %d", len);
211: goto failure;
212: }
213: memset(buf, 0, 32);
214: BN_bn2bin(challenge, buf + 32 - len);
215: MD5_Init(&md);
216: MD5_Update(&md, buf, 32);
217: MD5_Update(&md, session_id, 16);
218: MD5_Final(mdbuf, &md);
219:
220: /* Send the response. */
221: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
222: for (i = 0; i < 16; i++)
223: buffer_put_char(&msg, mdbuf[i]);
224: goto send;
225: }
1.21 markus 226:
1.33 markus 227: failure:
228: /* Unknown identity or protocol error. Send failure. */
1.21 markus 229: buffer_put_char(&msg, SSH_AGENT_FAILURE);
230: send:
231: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 232: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
233: key_free(key);
234: BN_clear_free(challenge);
235: buffer_free(&msg);
236: }
237:
238: /* ssh2 only */
1.55 itojun 239: static void
1.33 markus 240: process_sign_request2(SocketEntry *e)
241: {
242: extern int datafellows;
243: Key *key, *private;
1.45 markus 244: u_char *blob, *data, *signature = NULL;
245: u_int blen, dlen, slen = 0;
1.37 markus 246: int flags;
1.33 markus 247: Buffer msg;
248: int ok = -1;
249:
250: datafellows = 0;
1.43 markus 251:
1.33 markus 252: blob = buffer_get_string(&e->input, &blen);
253: data = buffer_get_string(&e->input, &dlen);
1.37 markus 254:
255: flags = buffer_get_int(&e->input);
256: if (flags & SSH_AGENT_OLD_SIGNATURE)
257: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 258:
1.39 markus 259: key = key_from_blob(blob, blen);
1.33 markus 260: if (key != NULL) {
261: private = lookup_private_key(key, NULL, 2);
262: if (private != NULL)
1.39 markus 263: ok = key_sign(private, &signature, &slen, data, dlen);
1.33 markus 264: }
265: key_free(key);
266: buffer_init(&msg);
267: if (ok == 0) {
268: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
269: buffer_put_string(&msg, signature, slen);
270: } else {
271: buffer_put_char(&msg, SSH_AGENT_FAILURE);
272: }
273: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 274: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 275: buffer_len(&msg));
1.21 markus 276: buffer_free(&msg);
1.33 markus 277: xfree(data);
278: xfree(blob);
279: if (signature != NULL)
280: xfree(signature);
1.1 deraadt 281: }
282:
1.33 markus 283: /* shared */
1.55 itojun 284: static void
1.33 markus 285: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 286: {
1.33 markus 287: Key *key = NULL, *private;
1.45 markus 288: u_char *blob;
289: u_int blen;
290: u_int bits;
1.33 markus 291: int success = 0;
1.21 markus 292:
1.74 deraadt 293: switch (version) {
1.33 markus 294: case 1:
1.39 markus 295: key = key_new(KEY_RSA1);
1.33 markus 296: bits = buffer_get_int(&e->input);
297: buffer_get_bignum(&e->input, key->rsa->e);
298: buffer_get_bignum(&e->input, key->rsa->n);
299:
300: if (bits != key_size(key))
301: log("Warning: identity keysize mismatch: actual %d, announced %d",
1.46 markus 302: key_size(key), bits);
1.33 markus 303: break;
304: case 2:
305: blob = buffer_get_string(&e->input, &blen);
1.39 markus 306: key = key_from_blob(blob, blen);
1.33 markus 307: xfree(blob);
308: break;
309: }
310: if (key != NULL) {
311: int idx;
312: private = lookup_private_key(key, &idx, version);
313: if (private != NULL) {
1.23 markus 314: /*
315: * We have this key. Free the old key. Since we
316: * don\'t want to leave empty slots in the middle of
1.40 markus 317: * the array, we actually free the key there and move
318: * all the entries between the empty slot and the end
319: * of the array.
1.23 markus 320: */
1.33 markus 321: Idtab *tab = idtab_lookup(version);
322: key_free(tab->identities[idx].key);
323: xfree(tab->identities[idx].comment);
1.38 markus 324: if (tab->nentries < 1)
325: fatal("process_remove_identity: "
326: "internal error: tab->nentries %d",
327: tab->nentries);
1.40 markus 328: if (idx != tab->nentries - 1) {
329: int i;
330: for (i = idx; i < tab->nentries - 1; i++)
331: tab->identities[i] = tab->identities[i+1];
332: }
333: tab->identities[tab->nentries - 1].key = NULL;
334: tab->identities[tab->nentries - 1].comment = NULL;
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: {
1.45 markus 348: u_int i;
1.33 markus 349: Idtab *tab = idtab_lookup(version);
1.21 markus 350:
351: /* Loop over all identities and clear the keys. */
1.33 markus 352: for (i = 0; i < tab->nentries; i++) {
353: key_free(tab->identities[i].key);
354: xfree(tab->identities[i].comment);
1.21 markus 355: }
356:
357: /* Mark that there are no identities. */
1.33 markus 358: tab->nentries = 0;
1.21 markus 359:
360: /* Send success. */
361: buffer_put_int(&e->output, 1);
362: buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
363: return;
1.1 deraadt 364: }
365:
1.55 itojun 366: static void
1.33 markus 367: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 368: {
1.33 markus 369: Key *k = NULL;
1.39 markus 370: char *type_name;
1.33 markus 371: char *comment;
1.39 markus 372: int type, success = 0;
1.33 markus 373: Idtab *tab = idtab_lookup(version);
374:
375: switch (version) {
376: case 1:
1.39 markus 377: k = key_new_private(KEY_RSA1);
1.46 markus 378: buffer_get_int(&e->input); /* ignored */
1.39 markus 379: buffer_get_bignum(&e->input, k->rsa->n);
380: buffer_get_bignum(&e->input, k->rsa->e);
381: buffer_get_bignum(&e->input, k->rsa->d);
382: buffer_get_bignum(&e->input, k->rsa->iqmp);
1.33 markus 383:
384: /* SSH and SSL have p and q swapped */
1.39 markus 385: buffer_get_bignum(&e->input, k->rsa->q); /* p */
386: buffer_get_bignum(&e->input, k->rsa->p); /* q */
1.33 markus 387:
388: /* Generate additional parameters */
1.60 markus 389: rsa_generate_additional_parameters(k->rsa);
1.33 markus 390: break;
391: case 2:
1.39 markus 392: type_name = buffer_get_string(&e->input, NULL);
1.46 markus 393: type = key_type_from_name(type_name);
1.39 markus 394: xfree(type_name);
1.74 deraadt 395: switch (type) {
1.39 markus 396: case KEY_DSA:
397: k = key_new_private(type);
398: buffer_get_bignum2(&e->input, k->dsa->p);
399: buffer_get_bignum2(&e->input, k->dsa->q);
400: buffer_get_bignum2(&e->input, k->dsa->g);
401: buffer_get_bignum2(&e->input, k->dsa->pub_key);
402: buffer_get_bignum2(&e->input, k->dsa->priv_key);
403: break;
404: case KEY_RSA:
405: k = key_new_private(type);
406: buffer_get_bignum2(&e->input, k->rsa->n);
407: buffer_get_bignum2(&e->input, k->rsa->e);
408: buffer_get_bignum2(&e->input, k->rsa->d);
409: buffer_get_bignum2(&e->input, k->rsa->iqmp);
410: buffer_get_bignum2(&e->input, k->rsa->p);
411: buffer_get_bignum2(&e->input, k->rsa->q);
412:
413: /* Generate additional parameters */
1.60 markus 414: rsa_generate_additional_parameters(k->rsa);
1.39 markus 415: break;
416: default:
1.33 markus 417: buffer_clear(&e->input);
418: goto send;
1.21 markus 419: }
1.33 markus 420: break;
421: }
422: comment = buffer_get_string(&e->input, NULL);
423: if (k == NULL) {
424: xfree(comment);
425: goto send;
426: }
427: success = 1;
428: if (lookup_private_key(k, NULL, version) == NULL) {
429: if (tab->nentries == 0)
430: tab->identities = xmalloc(sizeof(Identity));
431: else
432: tab->identities = xrealloc(tab->identities,
433: (tab->nentries + 1) * sizeof(Identity));
434: tab->identities[tab->nentries].key = k;
435: tab->identities[tab->nentries].comment = comment;
436: /* Increment the number of identities. */
437: tab->nentries++;
438: } else {
439: key_free(k);
440: xfree(comment);
441: }
442: send:
1.1 deraadt 443: buffer_put_int(&e->output, 1);
1.33 markus 444: buffer_put_char(&e->output,
445: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 446: }
447:
1.59 markus 448:
449: #ifdef SMARTCARD
450: static void
451: process_add_smartcard_key (SocketEntry *e)
452: {
453: Idtab *tab;
454: Key *n = NULL, *k = NULL;
1.69 markus 455: char *sc_reader_id = NULL;
1.59 markus 456: int success = 0;
1.75 deraadt 457:
1.69 markus 458: sc_reader_id = buffer_get_string(&e->input, NULL);
459: k = sc_get_key(sc_reader_id);
460: xfree(sc_reader_id);
1.59 markus 461:
462: if (k == NULL) {
463: error("sc_get_pubkey failed");
464: goto send;
465: }
466: success = 1;
467:
468: tab = idtab_lookup(1);
1.64 markus 469: k->type = KEY_RSA1;
1.59 markus 470: if (lookup_private_key(k, NULL, 1) == NULL) {
471: if (tab->nentries == 0)
472: tab->identities = xmalloc(sizeof(Identity));
473: else
474: tab->identities = xrealloc(tab->identities,
475: (tab->nentries + 1) * sizeof(Identity));
476: n = key_new(KEY_RSA1);
477: BN_copy(n->rsa->n, k->rsa->n);
478: BN_copy(n->rsa->e, k->rsa->e);
479: RSA_set_method(n->rsa, sc_get_engine());
480: tab->identities[tab->nentries].key = n;
481: tab->identities[tab->nentries].comment =
482: xstrdup("rsa1 smartcard");
483: tab->nentries++;
484: }
1.64 markus 485: k->type = KEY_RSA;
1.59 markus 486: tab = idtab_lookup(2);
487: if (lookup_private_key(k, NULL, 2) == NULL) {
488: if (tab->nentries == 0)
489: tab->identities = xmalloc(sizeof(Identity));
490: else
491: tab->identities = xrealloc(tab->identities,
492: (tab->nentries + 1) * sizeof(Identity));
493: n = key_new(KEY_RSA);
494: BN_copy(n->rsa->n, k->rsa->n);
495: BN_copy(n->rsa->e, k->rsa->e);
496: RSA_set_method(n->rsa, sc_get_engine());
497: tab->identities[tab->nentries].key = n;
498: tab->identities[tab->nentries].comment =
499: xstrdup("rsa smartcard");
500: tab->nentries++;
501: }
502: key_free(k);
503: send:
504: buffer_put_int(&e->output, 1);
505: buffer_put_char(&e->output,
506: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
507: }
508:
509: static void
510: process_remove_smartcard_key(SocketEntry *e)
511: {
512: Key *k = NULL, *private;
513: int idx;
514: int success = 0;
1.69 markus 515: char *sc_reader_id = NULL;
1.59 markus 516:
1.69 markus 517: sc_reader_id = buffer_get_string(&e->input, NULL);
518: k = sc_get_key(sc_reader_id);
519: xfree(sc_reader_id);
1.59 markus 520:
1.69 markus 521: if (k == NULL) {
1.59 markus 522: error("sc_get_pubkey failed");
523: } else {
1.63 markus 524: k->type = KEY_RSA1;
1.59 markus 525: private = lookup_private_key(k, &idx, 1);
526: if (private != NULL) {
527: Idtab *tab = idtab_lookup(1);
528: key_free(tab->identities[idx].key);
529: xfree(tab->identities[idx].comment);
530: if (idx != tab->nentries)
531: tab->identities[idx] = tab->identities[tab->nentries];
532: tab->nentries--;
533: success = 1;
534: }
1.63 markus 535: k->type = KEY_RSA;
1.59 markus 536: private = lookup_private_key(k, &idx, 2);
537: if (private != NULL) {
538: Idtab *tab = idtab_lookup(2);
539: key_free(tab->identities[idx].key);
540: xfree(tab->identities[idx].comment);
541: if (idx != tab->nentries)
542: tab->identities[idx] = tab->identities[tab->nentries];
543: tab->nentries--;
544: success = 1;
545: }
546: key_free(k);
547: }
548:
549: buffer_put_int(&e->output, 1);
550: buffer_put_char(&e->output,
551: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
552: }
1.70 jakob 553: #endif /* SMARTCARD */
1.59 markus 554:
1.33 markus 555: /* dispatch incoming messages */
556:
1.55 itojun 557: static void
1.2 provos 558: process_message(SocketEntry *e)
1.1 deraadt 559: {
1.45 markus 560: u_int msg_len;
561: u_int type;
562: u_char *cp;
1.21 markus 563: if (buffer_len(&e->input) < 5)
564: return; /* Incomplete message. */
1.77 ! stevesk 565: cp = buffer_ptr(&e->input);
1.21 markus 566: msg_len = GET_32BIT(cp);
567: if (msg_len > 256 * 1024) {
568: shutdown(e->fd, SHUT_RDWR);
569: close(e->fd);
570: e->type = AUTH_UNUSED;
571: return;
572: }
573: if (buffer_len(&e->input) < msg_len + 4)
574: return;
575: buffer_consume(&e->input, 4);
576: type = buffer_get_char(&e->input);
577:
1.59 markus 578: debug("type %d", type);
1.21 markus 579: switch (type) {
1.33 markus 580: /* ssh1 */
581: case SSH_AGENTC_RSA_CHALLENGE:
582: process_authentication_challenge1(e);
583: break;
1.21 markus 584: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 585: process_request_identities(e, 1);
1.21 markus 586: break;
587: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 588: process_add_identity(e, 1);
1.21 markus 589: break;
590: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 591: process_remove_identity(e, 1);
1.21 markus 592: break;
593: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 594: process_remove_all_identities(e, 1);
595: break;
596: /* ssh2 */
597: case SSH2_AGENTC_SIGN_REQUEST:
598: process_sign_request2(e);
599: break;
600: case SSH2_AGENTC_REQUEST_IDENTITIES:
601: process_request_identities(e, 2);
602: break;
603: case SSH2_AGENTC_ADD_IDENTITY:
604: process_add_identity(e, 2);
605: break;
606: case SSH2_AGENTC_REMOVE_IDENTITY:
607: process_remove_identity(e, 2);
608: break;
609: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
610: process_remove_all_identities(e, 2);
1.21 markus 611: break;
1.59 markus 612: #ifdef SMARTCARD
613: case SSH_AGENTC_ADD_SMARTCARD_KEY:
614: process_add_smartcard_key(e);
1.75 deraadt 615: break;
1.59 markus 616: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
617: process_remove_smartcard_key(e);
1.75 deraadt 618: break;
1.70 jakob 619: #endif /* SMARTCARD */
1.21 markus 620: default:
621: /* Unknown message. Respond with failure. */
622: error("Unknown message %d", type);
623: buffer_clear(&e->input);
624: buffer_put_int(&e->output, 1);
625: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
626: break;
627: }
1.1 deraadt 628: }
629:
1.55 itojun 630: static void
1.73 stevesk 631: new_socket(sock_type type, int fd)
1.1 deraadt 632: {
1.45 markus 633: u_int i, old_alloc;
1.21 markus 634: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
635: error("fcntl O_NONBLOCK: %s", strerror(errno));
636:
637: if (fd > max_fd)
638: max_fd = fd;
639:
640: for (i = 0; i < sockets_alloc; i++)
641: if (sockets[i].type == AUTH_UNUSED) {
642: sockets[i].fd = fd;
643: sockets[i].type = type;
644: buffer_init(&sockets[i].input);
645: buffer_init(&sockets[i].output);
646: return;
647: }
648: old_alloc = sockets_alloc;
649: sockets_alloc += 10;
650: if (sockets)
651: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
652: else
653: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
654: for (i = old_alloc; i < sockets_alloc; i++)
655: sockets[i].type = AUTH_UNUSED;
656: sockets[old_alloc].type = type;
657: sockets[old_alloc].fd = fd;
658: buffer_init(&sockets[old_alloc].input);
659: buffer_init(&sockets[old_alloc].output);
1.1 deraadt 660: }
661:
1.55 itojun 662: static int
1.66 markus 663: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 664: {
1.46 markus 665: u_int i, sz;
666: int n = 0;
667:
668: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 669: switch (sockets[i].type) {
670: case AUTH_SOCKET:
671: case AUTH_CONNECTION:
1.46 markus 672: n = MAX(n, sockets[i].fd);
1.21 markus 673: break;
674: case AUTH_UNUSED:
675: break;
676: default:
677: fatal("Unknown socket type %d", sockets[i].type);
678: break;
679: }
1.46 markus 680: }
681:
682: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 683: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 684: if (*fdrp)
1.54 stevesk 685: xfree(*fdrp);
1.46 markus 686: if (*fdwp)
1.54 stevesk 687: xfree(*fdwp);
1.46 markus 688: *fdrp = xmalloc(sz);
689: *fdwp = xmalloc(sz);
1.66 markus 690: *nallocp = sz;
1.46 markus 691: }
1.66 markus 692: if (n < *fdl)
693: debug("XXX shrink: %d < %d", n, *fdl);
694: *fdl = n;
1.46 markus 695: memset(*fdrp, 0, sz);
696: memset(*fdwp, 0, sz);
697:
698: for (i = 0; i < sockets_alloc; i++) {
699: switch (sockets[i].type) {
700: case AUTH_SOCKET:
701: case AUTH_CONNECTION:
702: FD_SET(sockets[i].fd, *fdrp);
703: if (buffer_len(&sockets[i].output) > 0)
704: FD_SET(sockets[i].fd, *fdwp);
705: break;
706: default:
707: break;
708: }
709: }
710: return (1);
1.21 markus 711: }
712:
1.55 itojun 713: static void
1.21 markus 714: after_select(fd_set *readset, fd_set *writeset)
715: {
1.45 markus 716: u_int i;
1.21 markus 717: int len, sock;
1.26 markus 718: socklen_t slen;
1.21 markus 719: char buf[1024];
720: struct sockaddr_un sunaddr;
721:
722: for (i = 0; i < sockets_alloc; i++)
723: switch (sockets[i].type) {
724: case AUTH_UNUSED:
725: break;
726: case AUTH_SOCKET:
727: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 728: slen = sizeof(sunaddr);
1.46 markus 729: sock = accept(sockets[i].fd,
730: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 731: if (sock < 0) {
732: perror("accept from AUTH_SOCKET");
733: break;
734: }
735: new_socket(AUTH_CONNECTION, sock);
736: }
737: break;
738: case AUTH_CONNECTION:
739: if (buffer_len(&sockets[i].output) > 0 &&
740: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 741: do {
742: len = write(sockets[i].fd,
743: buffer_ptr(&sockets[i].output),
744: buffer_len(&sockets[i].output));
745: if (len == -1 && (errno == EAGAIN ||
746: errno == EINTR))
747: continue;
748: break;
749: } while (1);
1.21 markus 750: if (len <= 0) {
751: shutdown(sockets[i].fd, SHUT_RDWR);
752: close(sockets[i].fd);
753: sockets[i].type = AUTH_UNUSED;
1.30 djm 754: buffer_free(&sockets[i].input);
755: buffer_free(&sockets[i].output);
1.21 markus 756: break;
757: }
758: buffer_consume(&sockets[i].output, len);
759: }
760: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 761: do {
762: len = read(sockets[i].fd, buf, sizeof(buf));
763: if (len == -1 && (errno == EAGAIN ||
764: errno == EINTR))
765: continue;
766: break;
767: } while (1);
1.21 markus 768: if (len <= 0) {
769: shutdown(sockets[i].fd, SHUT_RDWR);
770: close(sockets[i].fd);
771: sockets[i].type = AUTH_UNUSED;
1.30 djm 772: buffer_free(&sockets[i].input);
773: buffer_free(&sockets[i].output);
1.21 markus 774: break;
775: }
776: buffer_append(&sockets[i].input, buf, len);
777: process_message(&sockets[i]);
778: }
779: break;
780: default:
781: fatal("Unknown type %d", sockets[i].type);
782: }
1.1 deraadt 783: }
784:
1.55 itojun 785: static void
1.15 markus 786: cleanup_socket(void)
787: {
1.48 deraadt 788: if (socket_name[0])
789: unlink(socket_name);
790: if (socket_dir[0])
791: rmdir(socket_dir);
1.10 markus 792: }
793:
1.55 itojun 794: static void
1.15 markus 795: cleanup_exit(int i)
796: {
1.21 markus 797: cleanup_socket();
798: exit(i);
1.15 markus 799: }
800:
1.55 itojun 801: static void
1.48 deraadt 802: cleanup_handler(int sig)
803: {
804: cleanup_socket();
805: _exit(2);
1.68 markus 806: }
807:
808: static void
809: check_parent_exists(int sig)
810: {
811: int save_errno = errno;
812:
813: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
814: /* printf("Parent has died - Authentication agent exiting.\n"); */
815: cleanup_handler(sig); /* safe */
816: }
817: signal(SIGALRM, check_parent_exists);
818: alarm(10);
819: errno = save_errno;
1.48 deraadt 820: }
821:
1.55 itojun 822: static void
1.50 itojun 823: usage(void)
1.15 markus 824: {
1.72 jakob 825: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 826: __progname);
1.72 jakob 827: fprintf(stderr, "Options:\n");
828: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
829: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
830: fprintf(stderr, " -k Kill the current agent.\n");
831: fprintf(stderr, " -d Debug mode.\n");
1.21 markus 832: exit(1);
1.15 markus 833: }
834:
1.2 provos 835: int
836: main(int ac, char **av)
1.1 deraadt 837: {
1.66 markus 838: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 839: struct sockaddr_un sunaddr;
1.41 markus 840: struct rlimit rlim;
1.21 markus 841: pid_t pid;
842: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.43 markus 843: extern int optind;
1.46 markus 844: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 845:
846: SSLeay_add_all_algorithms();
1.21 markus 847:
1.57 markus 848: while ((ch = getopt(ac, av, "cdks")) != -1) {
1.21 markus 849: switch (ch) {
850: case 'c':
851: if (s_flag)
852: usage();
853: c_flag++;
854: break;
855: case 'k':
856: k_flag++;
857: break;
858: case 's':
859: if (c_flag)
860: usage();
861: s_flag++;
862: break;
1.57 markus 863: case 'd':
864: if (d_flag)
865: usage();
866: d_flag++;
867: break;
1.21 markus 868: default:
869: usage();
870: }
871: }
872: ac -= optind;
873: av += optind;
874:
1.57 markus 875: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 876: usage();
877:
1.57 markus 878: if (ac == 0 && !c_flag && !k_flag && !s_flag && !d_flag) {
1.21 markus 879: shell = getenv("SHELL");
880: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
881: c_flag = 1;
882: }
883: if (k_flag) {
884: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
885: if (pidstr == NULL) {
886: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 887: SSH_AGENTPID_ENV_NAME);
1.21 markus 888: exit(1);
889: }
890: pid = atoi(pidstr);
1.46 markus 891: if (pid < 1) {
1.21 markus 892: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 893: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 894: exit(1);
895: }
896: if (kill(pid, SIGTERM) == -1) {
897: perror("kill");
898: exit(1);
899: }
900: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
901: printf(format, SSH_AUTHSOCKET_ENV_NAME);
902: printf(format, SSH_AGENTPID_ENV_NAME);
903: printf("echo Agent pid %d killed;\n", pid);
904: exit(0);
905: }
906: parent_pid = getpid();
907:
908: /* Create private directory for agent socket */
909: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
910: if (mkdtemp(socket_dir) == NULL) {
911: perror("mkdtemp: private socket dir");
912: exit(1);
913: }
914: snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
1.46 markus 915: parent_pid);
1.21 markus 916:
1.23 markus 917: /*
918: * Create socket early so it will exist before command gets run from
919: * the parent.
920: */
1.21 markus 921: sock = socket(AF_UNIX, SOCK_STREAM, 0);
922: if (sock < 0) {
923: perror("socket");
924: cleanup_exit(1);
925: }
926: memset(&sunaddr, 0, sizeof(sunaddr));
927: sunaddr.sun_family = AF_UNIX;
928: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
929: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
930: perror("bind");
931: cleanup_exit(1);
932: }
933: if (listen(sock, 5) < 0) {
934: perror("listen");
935: cleanup_exit(1);
936: }
1.46 markus 937:
1.23 markus 938: /*
939: * Fork, and have the parent execute the command, if any, or present
940: * the socket data. The child continues as the authentication agent.
941: */
1.57 markus 942: if (d_flag) {
943: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
944: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
945: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
946: SSH_AUTHSOCKET_ENV_NAME);
947: printf("echo Agent pid %d;\n", parent_pid);
948: goto skip;
949: }
1.21 markus 950: pid = fork();
951: if (pid == -1) {
952: perror("fork");
953: exit(1);
954: }
955: if (pid != 0) { /* Parent - execute the given command. */
956: close(sock);
957: snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
958: if (ac == 0) {
959: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
960: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 961: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 962: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 963: SSH_AGENTPID_ENV_NAME);
1.21 markus 964: printf("echo Agent pid %d;\n", pid);
965: exit(0);
966: }
1.36 deraadt 967: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
968: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
969: perror("setenv");
970: exit(1);
971: }
1.21 markus 972: execvp(av[0], av);
973: perror(av[0]);
974: exit(1);
975: }
1.67 stevesk 976:
977: if (setsid() == -1) {
978: perror("setsid");
979: cleanup_exit(1);
980: }
981:
982: (void)chdir("/");
1.21 markus 983: close(0);
984: close(1);
985: close(2);
986:
1.41 markus 987: /* deny core dumps, since memory contains unencrypted private keys */
988: rlim.rlim_cur = rlim.rlim_max = 0;
989: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
990: perror("setrlimit rlimit_core failed");
1.21 markus 991: cleanup_exit(1);
992: }
1.57 markus 993:
994: skip:
1.21 markus 995: if (atexit(cleanup_socket) < 0) {
996: perror("atexit");
997: cleanup_exit(1);
998: }
999: new_socket(AUTH_SOCKET, sock);
1000: if (ac > 0) {
1001: signal(SIGALRM, check_parent_exists);
1002: alarm(10);
1003: }
1.33 markus 1004: idtab_init();
1.61 markus 1005: if (!d_flag)
1.57 markus 1006: signal(SIGINT, SIG_IGN);
1.61 markus 1007: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1008: signal(SIGHUP, cleanup_handler);
1009: signal(SIGTERM, cleanup_handler);
1.66 markus 1010: nalloc = 0;
1011:
1.21 markus 1012: while (1) {
1.66 markus 1013: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 1014: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 1015: if (errno == EINTR)
1016: continue;
1017: exit(1);
1018: }
1.46 markus 1019: after_select(readsetp, writesetp);
1.15 markus 1020: }
1.21 markus 1021: /* NOTREACHED */
1.1 deraadt 1022: }
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