Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.75
1.75 ! deraadt 1: /* $OpenBSD: ssh-agent.c,v 1.74 2001/12/05 10:06:12 deraadt 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"
1.75 ! deraadt 39: RCSID("$OpenBSD: ssh-agent.c,v 1.74 2001/12/05 10:06:12 deraadt 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);
1.21 markus 185: challenge = BN_new();
1.33 markus 186:
187: buffer_get_int(&e->input); /* ignored */
188: buffer_get_bignum(&e->input, key->rsa->e);
189: buffer_get_bignum(&e->input, key->rsa->n);
1.21 markus 190: buffer_get_bignum(&e->input, challenge);
191:
1.33 markus 192: /* Only protocol 1.1 is supported */
193: if (buffer_len(&e->input) == 0)
194: goto failure;
195: buffer_get(&e->input, (char *) session_id, 16);
196: response_type = buffer_get_int(&e->input);
197: if (response_type != 1)
198: goto failure;
199:
200: private = lookup_private_key(key, NULL, 1);
201: if (private != NULL) {
202: /* Decrypt the challenge using the private key. */
1.49 markus 203: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
204: goto failure;
1.33 markus 205:
206: /* The response is MD5 of decrypted challenge plus session id. */
207: len = BN_num_bytes(challenge);
208: if (len <= 0 || len > 32) {
209: log("process_authentication_challenge: bad challenge length %d", len);
210: goto failure;
211: }
212: memset(buf, 0, 32);
213: BN_bn2bin(challenge, buf + 32 - len);
214: MD5_Init(&md);
215: MD5_Update(&md, buf, 32);
216: MD5_Update(&md, session_id, 16);
217: MD5_Final(mdbuf, &md);
218:
219: /* Send the response. */
220: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
221: for (i = 0; i < 16; i++)
222: buffer_put_char(&msg, mdbuf[i]);
223: goto send;
224: }
1.21 markus 225:
1.33 markus 226: failure:
227: /* Unknown identity or protocol error. Send failure. */
1.21 markus 228: buffer_put_char(&msg, SSH_AGENT_FAILURE);
229: send:
230: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 231: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
232: key_free(key);
233: BN_clear_free(challenge);
234: buffer_free(&msg);
235: }
236:
237: /* ssh2 only */
1.55 itojun 238: static void
1.33 markus 239: process_sign_request2(SocketEntry *e)
240: {
241: extern int datafellows;
242: Key *key, *private;
1.45 markus 243: u_char *blob, *data, *signature = NULL;
244: u_int blen, dlen, slen = 0;
1.37 markus 245: int flags;
1.33 markus 246: Buffer msg;
247: int ok = -1;
248:
249: datafellows = 0;
1.43 markus 250:
1.33 markus 251: blob = buffer_get_string(&e->input, &blen);
252: data = buffer_get_string(&e->input, &dlen);
1.37 markus 253:
254: flags = buffer_get_int(&e->input);
255: if (flags & SSH_AGENT_OLD_SIGNATURE)
256: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 257:
1.39 markus 258: key = key_from_blob(blob, blen);
1.33 markus 259: if (key != NULL) {
260: private = lookup_private_key(key, NULL, 2);
261: if (private != NULL)
1.39 markus 262: ok = key_sign(private, &signature, &slen, data, dlen);
1.33 markus 263: }
264: key_free(key);
265: buffer_init(&msg);
266: if (ok == 0) {
267: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
268: buffer_put_string(&msg, signature, slen);
269: } else {
270: buffer_put_char(&msg, SSH_AGENT_FAILURE);
271: }
272: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 273: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 274: buffer_len(&msg));
1.21 markus 275: buffer_free(&msg);
1.33 markus 276: xfree(data);
277: xfree(blob);
278: if (signature != NULL)
279: xfree(signature);
1.1 deraadt 280: }
281:
1.33 markus 282: /* shared */
1.55 itojun 283: static void
1.33 markus 284: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 285: {
1.33 markus 286: Key *key = NULL, *private;
1.45 markus 287: u_char *blob;
288: u_int blen;
289: u_int bits;
1.33 markus 290: int success = 0;
1.21 markus 291:
1.74 deraadt 292: switch (version) {
1.33 markus 293: case 1:
1.39 markus 294: key = key_new(KEY_RSA1);
1.33 markus 295: bits = buffer_get_int(&e->input);
296: buffer_get_bignum(&e->input, key->rsa->e);
297: buffer_get_bignum(&e->input, key->rsa->n);
298:
299: if (bits != key_size(key))
300: log("Warning: identity keysize mismatch: actual %d, announced %d",
1.46 markus 301: key_size(key), bits);
1.33 markus 302: break;
303: case 2:
304: blob = buffer_get_string(&e->input, &blen);
1.39 markus 305: key = key_from_blob(blob, blen);
1.33 markus 306: xfree(blob);
307: break;
308: }
309: if (key != NULL) {
310: int idx;
311: private = lookup_private_key(key, &idx, version);
312: if (private != NULL) {
1.23 markus 313: /*
314: * We have this key. Free the old key. Since we
315: * don\'t want to leave empty slots in the middle of
1.40 markus 316: * the array, we actually free the key there and move
317: * all the entries between the empty slot and the end
318: * of the array.
1.23 markus 319: */
1.33 markus 320: Idtab *tab = idtab_lookup(version);
321: key_free(tab->identities[idx].key);
322: xfree(tab->identities[idx].comment);
1.38 markus 323: if (tab->nentries < 1)
324: fatal("process_remove_identity: "
325: "internal error: tab->nentries %d",
326: tab->nentries);
1.40 markus 327: if (idx != tab->nentries - 1) {
328: int i;
329: for (i = idx; i < tab->nentries - 1; i++)
330: tab->identities[i] = tab->identities[i+1];
331: }
332: tab->identities[tab->nentries - 1].key = NULL;
333: tab->identities[tab->nentries - 1].comment = NULL;
1.33 markus 334: tab->nentries--;
335: success = 1;
1.21 markus 336: }
1.33 markus 337: key_free(key);
338: }
1.1 deraadt 339: buffer_put_int(&e->output, 1);
1.33 markus 340: buffer_put_char(&e->output,
341: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 342: }
343:
1.55 itojun 344: static void
1.33 markus 345: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 346: {
1.45 markus 347: u_int i;
1.33 markus 348: Idtab *tab = idtab_lookup(version);
1.21 markus 349:
350: /* Loop over all identities and clear the keys. */
1.33 markus 351: for (i = 0; i < tab->nentries; i++) {
352: key_free(tab->identities[i].key);
353: xfree(tab->identities[i].comment);
1.21 markus 354: }
355:
356: /* Mark that there are no identities. */
1.33 markus 357: tab->nentries = 0;
1.21 markus 358:
359: /* Send success. */
360: buffer_put_int(&e->output, 1);
361: buffer_put_char(&e->output, SSH_AGENT_SUCCESS);
362: return;
1.1 deraadt 363: }
364:
1.55 itojun 365: static void
1.33 markus 366: process_add_identity(SocketEntry *e, int version)
1.1 deraadt 367: {
1.33 markus 368: Key *k = NULL;
1.39 markus 369: char *type_name;
1.33 markus 370: char *comment;
1.39 markus 371: int type, success = 0;
1.33 markus 372: Idtab *tab = idtab_lookup(version);
373:
374: switch (version) {
375: case 1:
1.39 markus 376: k = key_new_private(KEY_RSA1);
1.46 markus 377: buffer_get_int(&e->input); /* ignored */
1.39 markus 378: buffer_get_bignum(&e->input, k->rsa->n);
379: buffer_get_bignum(&e->input, k->rsa->e);
380: buffer_get_bignum(&e->input, k->rsa->d);
381: buffer_get_bignum(&e->input, k->rsa->iqmp);
1.33 markus 382:
383: /* SSH and SSL have p and q swapped */
1.39 markus 384: buffer_get_bignum(&e->input, k->rsa->q); /* p */
385: buffer_get_bignum(&e->input, k->rsa->p); /* q */
1.33 markus 386:
387: /* Generate additional parameters */
1.60 markus 388: rsa_generate_additional_parameters(k->rsa);
1.33 markus 389: break;
390: case 2:
1.39 markus 391: type_name = buffer_get_string(&e->input, NULL);
1.46 markus 392: type = key_type_from_name(type_name);
1.39 markus 393: xfree(type_name);
1.74 deraadt 394: switch (type) {
1.39 markus 395: case KEY_DSA:
396: k = key_new_private(type);
397: buffer_get_bignum2(&e->input, k->dsa->p);
398: buffer_get_bignum2(&e->input, k->dsa->q);
399: buffer_get_bignum2(&e->input, k->dsa->g);
400: buffer_get_bignum2(&e->input, k->dsa->pub_key);
401: buffer_get_bignum2(&e->input, k->dsa->priv_key);
402: break;
403: case KEY_RSA:
404: k = key_new_private(type);
405: buffer_get_bignum2(&e->input, k->rsa->n);
406: buffer_get_bignum2(&e->input, k->rsa->e);
407: buffer_get_bignum2(&e->input, k->rsa->d);
408: buffer_get_bignum2(&e->input, k->rsa->iqmp);
409: buffer_get_bignum2(&e->input, k->rsa->p);
410: buffer_get_bignum2(&e->input, k->rsa->q);
411:
412: /* Generate additional parameters */
1.60 markus 413: rsa_generate_additional_parameters(k->rsa);
1.39 markus 414: break;
415: default:
1.33 markus 416: buffer_clear(&e->input);
417: goto send;
1.21 markus 418: }
1.33 markus 419: break;
420: }
421: comment = buffer_get_string(&e->input, NULL);
422: if (k == NULL) {
423: xfree(comment);
424: goto send;
425: }
426: success = 1;
427: if (lookup_private_key(k, NULL, version) == NULL) {
428: if (tab->nentries == 0)
429: tab->identities = xmalloc(sizeof(Identity));
430: else
431: tab->identities = xrealloc(tab->identities,
432: (tab->nentries + 1) * sizeof(Identity));
433: tab->identities[tab->nentries].key = k;
434: tab->identities[tab->nentries].comment = comment;
435: /* Increment the number of identities. */
436: tab->nentries++;
437: } else {
438: key_free(k);
439: xfree(comment);
440: }
441: send:
1.1 deraadt 442: buffer_put_int(&e->output, 1);
1.33 markus 443: buffer_put_char(&e->output,
444: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 445: }
446:
1.59 markus 447:
448: #ifdef SMARTCARD
449: static void
450: process_add_smartcard_key (SocketEntry *e)
451: {
452: Idtab *tab;
453: Key *n = NULL, *k = NULL;
1.69 markus 454: char *sc_reader_id = NULL;
1.59 markus 455: int success = 0;
1.75 ! deraadt 456:
1.69 markus 457: sc_reader_id = buffer_get_string(&e->input, NULL);
458: k = sc_get_key(sc_reader_id);
459: xfree(sc_reader_id);
1.59 markus 460:
461: if (k == NULL) {
462: error("sc_get_pubkey failed");
463: goto send;
464: }
465: success = 1;
466:
467: tab = idtab_lookup(1);
1.64 markus 468: k->type = KEY_RSA1;
1.59 markus 469: if (lookup_private_key(k, NULL, 1) == NULL) {
470: if (tab->nentries == 0)
471: tab->identities = xmalloc(sizeof(Identity));
472: else
473: tab->identities = xrealloc(tab->identities,
474: (tab->nentries + 1) * sizeof(Identity));
475: n = key_new(KEY_RSA1);
476: BN_copy(n->rsa->n, k->rsa->n);
477: BN_copy(n->rsa->e, k->rsa->e);
478: RSA_set_method(n->rsa, sc_get_engine());
479: tab->identities[tab->nentries].key = n;
480: tab->identities[tab->nentries].comment =
481: xstrdup("rsa1 smartcard");
482: tab->nentries++;
483: }
1.64 markus 484: k->type = KEY_RSA;
1.59 markus 485: tab = idtab_lookup(2);
486: if (lookup_private_key(k, NULL, 2) == NULL) {
487: if (tab->nentries == 0)
488: tab->identities = xmalloc(sizeof(Identity));
489: else
490: tab->identities = xrealloc(tab->identities,
491: (tab->nentries + 1) * sizeof(Identity));
492: n = key_new(KEY_RSA);
493: BN_copy(n->rsa->n, k->rsa->n);
494: BN_copy(n->rsa->e, k->rsa->e);
495: RSA_set_method(n->rsa, sc_get_engine());
496: tab->identities[tab->nentries].key = n;
497: tab->identities[tab->nentries].comment =
498: xstrdup("rsa smartcard");
499: tab->nentries++;
500: }
501: key_free(k);
502: send:
503: buffer_put_int(&e->output, 1);
504: buffer_put_char(&e->output,
505: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
506: }
507:
508: static void
509: process_remove_smartcard_key(SocketEntry *e)
510: {
511: Key *k = NULL, *private;
512: int idx;
513: int success = 0;
1.69 markus 514: char *sc_reader_id = NULL;
1.59 markus 515:
1.69 markus 516: sc_reader_id = buffer_get_string(&e->input, NULL);
517: k = sc_get_key(sc_reader_id);
518: xfree(sc_reader_id);
1.59 markus 519:
1.69 markus 520: if (k == NULL) {
1.59 markus 521: error("sc_get_pubkey failed");
522: } else {
1.63 markus 523: k->type = KEY_RSA1;
1.59 markus 524: private = lookup_private_key(k, &idx, 1);
525: if (private != NULL) {
526: Idtab *tab = idtab_lookup(1);
527: key_free(tab->identities[idx].key);
528: xfree(tab->identities[idx].comment);
529: if (idx != tab->nentries)
530: tab->identities[idx] = tab->identities[tab->nentries];
531: tab->nentries--;
532: success = 1;
533: }
1.63 markus 534: k->type = KEY_RSA;
1.59 markus 535: private = lookup_private_key(k, &idx, 2);
536: if (private != NULL) {
537: Idtab *tab = idtab_lookup(2);
538: key_free(tab->identities[idx].key);
539: xfree(tab->identities[idx].comment);
540: if (idx != tab->nentries)
541: tab->identities[idx] = tab->identities[tab->nentries];
542: tab->nentries--;
543: success = 1;
544: }
545: key_free(k);
546: }
547:
548: buffer_put_int(&e->output, 1);
549: buffer_put_char(&e->output,
550: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
551: }
1.70 jakob 552: #endif /* SMARTCARD */
1.59 markus 553:
1.33 markus 554: /* dispatch incoming messages */
555:
1.55 itojun 556: static void
1.2 provos 557: process_message(SocketEntry *e)
1.1 deraadt 558: {
1.45 markus 559: u_int msg_len;
560: u_int type;
561: u_char *cp;
1.21 markus 562: if (buffer_len(&e->input) < 5)
563: return; /* Incomplete message. */
1.45 markus 564: cp = (u_char *) buffer_ptr(&e->input);
1.21 markus 565: msg_len = GET_32BIT(cp);
566: if (msg_len > 256 * 1024) {
567: shutdown(e->fd, SHUT_RDWR);
568: close(e->fd);
569: e->type = AUTH_UNUSED;
570: return;
571: }
572: if (buffer_len(&e->input) < msg_len + 4)
573: return;
574: buffer_consume(&e->input, 4);
575: type = buffer_get_char(&e->input);
576:
1.59 markus 577: debug("type %d", type);
1.21 markus 578: switch (type) {
1.33 markus 579: /* ssh1 */
580: case SSH_AGENTC_RSA_CHALLENGE:
581: process_authentication_challenge1(e);
582: break;
1.21 markus 583: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 584: process_request_identities(e, 1);
1.21 markus 585: break;
586: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 587: process_add_identity(e, 1);
1.21 markus 588: break;
589: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 590: process_remove_identity(e, 1);
1.21 markus 591: break;
592: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 593: process_remove_all_identities(e, 1);
594: break;
595: /* ssh2 */
596: case SSH2_AGENTC_SIGN_REQUEST:
597: process_sign_request2(e);
598: break;
599: case SSH2_AGENTC_REQUEST_IDENTITIES:
600: process_request_identities(e, 2);
601: break;
602: case SSH2_AGENTC_ADD_IDENTITY:
603: process_add_identity(e, 2);
604: break;
605: case SSH2_AGENTC_REMOVE_IDENTITY:
606: process_remove_identity(e, 2);
607: break;
608: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
609: process_remove_all_identities(e, 2);
1.21 markus 610: break;
1.59 markus 611: #ifdef SMARTCARD
612: case SSH_AGENTC_ADD_SMARTCARD_KEY:
613: process_add_smartcard_key(e);
1.75 ! deraadt 614: break;
1.59 markus 615: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
616: process_remove_smartcard_key(e);
1.75 ! deraadt 617: break;
1.70 jakob 618: #endif /* SMARTCARD */
1.21 markus 619: default:
620: /* Unknown message. Respond with failure. */
621: error("Unknown message %d", type);
622: buffer_clear(&e->input);
623: buffer_put_int(&e->output, 1);
624: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
625: break;
626: }
1.1 deraadt 627: }
628:
1.55 itojun 629: static void
1.73 stevesk 630: new_socket(sock_type type, int fd)
1.1 deraadt 631: {
1.45 markus 632: u_int i, old_alloc;
1.21 markus 633: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
634: error("fcntl O_NONBLOCK: %s", strerror(errno));
635:
636: if (fd > max_fd)
637: max_fd = fd;
638:
639: for (i = 0; i < sockets_alloc; i++)
640: if (sockets[i].type == AUTH_UNUSED) {
641: sockets[i].fd = fd;
642: sockets[i].type = type;
643: buffer_init(&sockets[i].input);
644: buffer_init(&sockets[i].output);
645: return;
646: }
647: old_alloc = sockets_alloc;
648: sockets_alloc += 10;
649: if (sockets)
650: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
651: else
652: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
653: for (i = old_alloc; i < sockets_alloc; i++)
654: sockets[i].type = AUTH_UNUSED;
655: sockets[old_alloc].type = type;
656: sockets[old_alloc].fd = fd;
657: buffer_init(&sockets[old_alloc].input);
658: buffer_init(&sockets[old_alloc].output);
1.1 deraadt 659: }
660:
1.55 itojun 661: static int
1.66 markus 662: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 663: {
1.46 markus 664: u_int i, sz;
665: int n = 0;
666:
667: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 668: switch (sockets[i].type) {
669: case AUTH_SOCKET:
670: case AUTH_CONNECTION:
1.46 markus 671: n = MAX(n, sockets[i].fd);
1.21 markus 672: break;
673: case AUTH_UNUSED:
674: break;
675: default:
676: fatal("Unknown socket type %d", sockets[i].type);
677: break;
678: }
1.46 markus 679: }
680:
681: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.66 markus 682: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 683: if (*fdrp)
1.54 stevesk 684: xfree(*fdrp);
1.46 markus 685: if (*fdwp)
1.54 stevesk 686: xfree(*fdwp);
1.46 markus 687: *fdrp = xmalloc(sz);
688: *fdwp = xmalloc(sz);
1.66 markus 689: *nallocp = sz;
1.46 markus 690: }
1.66 markus 691: if (n < *fdl)
692: debug("XXX shrink: %d < %d", n, *fdl);
693: *fdl = n;
1.46 markus 694: memset(*fdrp, 0, sz);
695: memset(*fdwp, 0, sz);
696:
697: for (i = 0; i < sockets_alloc; i++) {
698: switch (sockets[i].type) {
699: case AUTH_SOCKET:
700: case AUTH_CONNECTION:
701: FD_SET(sockets[i].fd, *fdrp);
702: if (buffer_len(&sockets[i].output) > 0)
703: FD_SET(sockets[i].fd, *fdwp);
704: break;
705: default:
706: break;
707: }
708: }
709: return (1);
1.21 markus 710: }
711:
1.55 itojun 712: static void
1.21 markus 713: after_select(fd_set *readset, fd_set *writeset)
714: {
1.45 markus 715: u_int i;
1.21 markus 716: int len, sock;
1.26 markus 717: socklen_t slen;
1.21 markus 718: char buf[1024];
719: struct sockaddr_un sunaddr;
720:
721: for (i = 0; i < sockets_alloc; i++)
722: switch (sockets[i].type) {
723: case AUTH_UNUSED:
724: break;
725: case AUTH_SOCKET:
726: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 727: slen = sizeof(sunaddr);
1.46 markus 728: sock = accept(sockets[i].fd,
729: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 730: if (sock < 0) {
731: perror("accept from AUTH_SOCKET");
732: break;
733: }
734: new_socket(AUTH_CONNECTION, sock);
735: }
736: break;
737: case AUTH_CONNECTION:
738: if (buffer_len(&sockets[i].output) > 0 &&
739: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 740: do {
741: len = write(sockets[i].fd,
742: buffer_ptr(&sockets[i].output),
743: buffer_len(&sockets[i].output));
744: if (len == -1 && (errno == EAGAIN ||
745: errno == EINTR))
746: continue;
747: break;
748: } while (1);
1.21 markus 749: if (len <= 0) {
750: shutdown(sockets[i].fd, SHUT_RDWR);
751: close(sockets[i].fd);
752: sockets[i].type = AUTH_UNUSED;
1.30 djm 753: buffer_free(&sockets[i].input);
754: buffer_free(&sockets[i].output);
1.21 markus 755: break;
756: }
757: buffer_consume(&sockets[i].output, len);
758: }
759: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 760: do {
761: len = read(sockets[i].fd, buf, sizeof(buf));
762: if (len == -1 && (errno == EAGAIN ||
763: errno == EINTR))
764: continue;
765: break;
766: } while (1);
1.21 markus 767: if (len <= 0) {
768: shutdown(sockets[i].fd, SHUT_RDWR);
769: close(sockets[i].fd);
770: sockets[i].type = AUTH_UNUSED;
1.30 djm 771: buffer_free(&sockets[i].input);
772: buffer_free(&sockets[i].output);
1.21 markus 773: break;
774: }
775: buffer_append(&sockets[i].input, buf, len);
776: process_message(&sockets[i]);
777: }
778: break;
779: default:
780: fatal("Unknown type %d", sockets[i].type);
781: }
1.1 deraadt 782: }
783:
1.55 itojun 784: static void
1.15 markus 785: cleanup_socket(void)
786: {
1.48 deraadt 787: if (socket_name[0])
788: unlink(socket_name);
789: if (socket_dir[0])
790: rmdir(socket_dir);
1.10 markus 791: }
792:
1.55 itojun 793: static void
1.15 markus 794: cleanup_exit(int i)
795: {
1.21 markus 796: cleanup_socket();
797: exit(i);
1.15 markus 798: }
799:
1.55 itojun 800: static void
1.48 deraadt 801: cleanup_handler(int sig)
802: {
803: cleanup_socket();
804: _exit(2);
1.68 markus 805: }
806:
807: static void
808: check_parent_exists(int sig)
809: {
810: int save_errno = errno;
811:
812: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
813: /* printf("Parent has died - Authentication agent exiting.\n"); */
814: cleanup_handler(sig); /* safe */
815: }
816: signal(SIGALRM, check_parent_exists);
817: alarm(10);
818: errno = save_errno;
1.48 deraadt 819: }
820:
1.55 itojun 821: static void
1.50 itojun 822: usage(void)
1.15 markus 823: {
1.72 jakob 824: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 825: __progname);
1.72 jakob 826: fprintf(stderr, "Options:\n");
827: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
828: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
829: fprintf(stderr, " -k Kill the current agent.\n");
830: fprintf(stderr, " -d Debug mode.\n");
1.21 markus 831: exit(1);
1.15 markus 832: }
833:
1.2 provos 834: int
835: main(int ac, char **av)
1.1 deraadt 836: {
1.66 markus 837: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 838: struct sockaddr_un sunaddr;
1.41 markus 839: struct rlimit rlim;
1.21 markus 840: pid_t pid;
841: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.43 markus 842: extern int optind;
1.46 markus 843: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 844:
845: SSLeay_add_all_algorithms();
1.21 markus 846:
1.57 markus 847: while ((ch = getopt(ac, av, "cdks")) != -1) {
1.21 markus 848: switch (ch) {
849: case 'c':
850: if (s_flag)
851: usage();
852: c_flag++;
853: break;
854: case 'k':
855: k_flag++;
856: break;
857: case 's':
858: if (c_flag)
859: usage();
860: s_flag++;
861: break;
1.57 markus 862: case 'd':
863: if (d_flag)
864: usage();
865: d_flag++;
866: break;
1.21 markus 867: default:
868: usage();
869: }
870: }
871: ac -= optind;
872: av += optind;
873:
1.57 markus 874: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 875: usage();
876:
1.57 markus 877: if (ac == 0 && !c_flag && !k_flag && !s_flag && !d_flag) {
1.21 markus 878: shell = getenv("SHELL");
879: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
880: c_flag = 1;
881: }
882: if (k_flag) {
883: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
884: if (pidstr == NULL) {
885: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 886: SSH_AGENTPID_ENV_NAME);
1.21 markus 887: exit(1);
888: }
889: pid = atoi(pidstr);
1.46 markus 890: if (pid < 1) {
1.21 markus 891: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 892: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 893: exit(1);
894: }
895: if (kill(pid, SIGTERM) == -1) {
896: perror("kill");
897: exit(1);
898: }
899: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
900: printf(format, SSH_AUTHSOCKET_ENV_NAME);
901: printf(format, SSH_AGENTPID_ENV_NAME);
902: printf("echo Agent pid %d killed;\n", pid);
903: exit(0);
904: }
905: parent_pid = getpid();
906:
907: /* Create private directory for agent socket */
908: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
909: if (mkdtemp(socket_dir) == NULL) {
910: perror("mkdtemp: private socket dir");
911: exit(1);
912: }
913: snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
1.46 markus 914: parent_pid);
1.21 markus 915:
1.23 markus 916: /*
917: * Create socket early so it will exist before command gets run from
918: * the parent.
919: */
1.21 markus 920: sock = socket(AF_UNIX, SOCK_STREAM, 0);
921: if (sock < 0) {
922: perror("socket");
923: cleanup_exit(1);
924: }
925: memset(&sunaddr, 0, sizeof(sunaddr));
926: sunaddr.sun_family = AF_UNIX;
927: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
928: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
929: perror("bind");
930: cleanup_exit(1);
931: }
932: if (listen(sock, 5) < 0) {
933: perror("listen");
934: cleanup_exit(1);
935: }
1.46 markus 936:
1.23 markus 937: /*
938: * Fork, and have the parent execute the command, if any, or present
939: * the socket data. The child continues as the authentication agent.
940: */
1.57 markus 941: if (d_flag) {
942: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
943: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
944: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
945: SSH_AUTHSOCKET_ENV_NAME);
946: printf("echo Agent pid %d;\n", parent_pid);
947: goto skip;
948: }
1.21 markus 949: pid = fork();
950: if (pid == -1) {
951: perror("fork");
952: exit(1);
953: }
954: if (pid != 0) { /* Parent - execute the given command. */
955: close(sock);
956: snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
957: if (ac == 0) {
958: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
959: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 960: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 961: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 962: SSH_AGENTPID_ENV_NAME);
1.21 markus 963: printf("echo Agent pid %d;\n", pid);
964: exit(0);
965: }
1.36 deraadt 966: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
967: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
968: perror("setenv");
969: exit(1);
970: }
1.21 markus 971: execvp(av[0], av);
972: perror(av[0]);
973: exit(1);
974: }
1.67 stevesk 975:
976: if (setsid() == -1) {
977: perror("setsid");
978: cleanup_exit(1);
979: }
980:
981: (void)chdir("/");
1.21 markus 982: close(0);
983: close(1);
984: close(2);
985:
1.41 markus 986: /* deny core dumps, since memory contains unencrypted private keys */
987: rlim.rlim_cur = rlim.rlim_max = 0;
988: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
989: perror("setrlimit rlimit_core failed");
1.21 markus 990: cleanup_exit(1);
991: }
1.57 markus 992:
993: skip:
1.21 markus 994: if (atexit(cleanup_socket) < 0) {
995: perror("atexit");
996: cleanup_exit(1);
997: }
998: new_socket(AUTH_SOCKET, sock);
999: if (ac > 0) {
1000: signal(SIGALRM, check_parent_exists);
1001: alarm(10);
1002: }
1.33 markus 1003: idtab_init();
1.61 markus 1004: if (!d_flag)
1.57 markus 1005: signal(SIGINT, SIG_IGN);
1.61 markus 1006: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1007: signal(SIGHUP, cleanup_handler);
1008: signal(SIGTERM, cleanup_handler);
1.66 markus 1009: nalloc = 0;
1010:
1.21 markus 1011: while (1) {
1.66 markus 1012: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 1013: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 1014: if (errno == EINTR)
1015: continue;
1016: exit(1);
1017: }
1.46 markus 1018: after_select(readsetp, writesetp);
1.15 markus 1019: }
1.21 markus 1020: /* NOTREACHED */
1.1 deraadt 1021: }
![[BACK]](/icons/back.gif){kind=icon}
Return to ssh-agent.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh