Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.54.2.1
1.54.2.1! jason 1: /* $OpenBSD: ssh-agent.c,v 1.72 2001/08/03 10:31:30 jakob 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: *
1.54.2.1! jason 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"
1.54.2.1! jason 39: RCSID("$OpenBSD: ssh-agent.c,v 1.72 2001/08/03 10:31:30 jakob 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:
1.54.2.1! jason 59: #ifdef SMARTCARD
! 60: #include <openssl/engine.h>
! 61: #include "scard.h"
! 62: #endif
! 63:
1.21 markus 64: typedef struct {
65: int fd;
66: enum {
67: AUTH_UNUSED, AUTH_SOCKET, AUTH_CONNECTION
68: } type;
69: Buffer input;
70: Buffer output;
1.1 deraadt 71: } SocketEntry;
72:
1.45 markus 73: u_int sockets_alloc = 0;
1.1 deraadt 74: SocketEntry *sockets = NULL;
75:
1.21 markus 76: typedef struct {
1.33 markus 77: Key *key;
1.21 markus 78: char *comment;
1.1 deraadt 79: } Identity;
80:
1.33 markus 81: typedef struct {
82: int nentries;
83: Identity *identities;
84: } Idtab;
85:
86: /* private key table, one per protocol version */
87: Idtab idtable[3];
1.1 deraadt 88:
89: int max_fd = 0;
90:
1.11 markus 91: /* pid of shell == parent of agent */
1.29 deraadt 92: pid_t parent_pid = -1;
1.10 markus 93:
94: /* pathname and directory for AUTH_SOCKET */
95: char socket_name[1024];
96: char socket_dir[1024];
97:
1.20 markus 98: extern char *__progname;
99:
1.54.2.1! jason 100: static void
1.33 markus 101: idtab_init(void)
1.1 deraadt 102: {
1.33 markus 103: int i;
104: for (i = 0; i <=2; i++){
105: idtable[i].identities = NULL;
106: idtable[i].nentries = 0;
107: }
108: }
109:
110: /* return private key table for requested protocol version */
1.54.2.1! jason 111: static Idtab *
1.33 markus 112: idtab_lookup(int version)
113: {
114: if (version < 1 || version > 2)
115: fatal("internal error, bad protocol version %d", version);
116: return &idtable[version];
117: }
118:
119: /* return matching private key for given public key */
1.54.2.1! jason 120: static Key *
1.33 markus 121: lookup_private_key(Key *key, int *idx, int version)
122: {
123: int i;
124: Idtab *tab = idtab_lookup(version);
125: for (i = 0; i < tab->nentries; i++) {
126: if (key_equal(key, tab->identities[i].key)) {
127: if (idx != NULL)
128: *idx = i;
129: return tab->identities[i].key;
130: }
131: }
132: return NULL;
133: }
134:
135: /* send list of supported public keys to 'client' */
1.54.2.1! jason 136: static void
1.33 markus 137: process_request_identities(SocketEntry *e, int version)
138: {
139: Idtab *tab = idtab_lookup(version);
1.21 markus 140: Buffer msg;
141: int i;
1.1 deraadt 142:
1.21 markus 143: buffer_init(&msg);
1.33 markus 144: buffer_put_char(&msg, (version == 1) ?
145: SSH_AGENT_RSA_IDENTITIES_ANSWER : SSH2_AGENT_IDENTITIES_ANSWER);
146: buffer_put_int(&msg, tab->nentries);
147: for (i = 0; i < tab->nentries; i++) {
148: Identity *id = &tab->identities[i];
1.39 markus 149: if (id->key->type == KEY_RSA1) {
1.33 markus 150: buffer_put_int(&msg, BN_num_bits(id->key->rsa->n));
151: buffer_put_bignum(&msg, id->key->rsa->e);
152: buffer_put_bignum(&msg, id->key->rsa->n);
153: } else {
1.45 markus 154: u_char *blob;
155: u_int blen;
1.39 markus 156: key_to_blob(id->key, &blob, &blen);
1.33 markus 157: buffer_put_string(&msg, blob, blen);
158: xfree(blob);
159: }
160: buffer_put_cstring(&msg, id->comment);
1.21 markus 161: }
162: buffer_put_int(&e->output, buffer_len(&msg));
163: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
164: buffer_free(&msg);
1.1 deraadt 165: }
166:
1.33 markus 167: /* ssh1 only */
1.54.2.1! jason 168: static void
1.33 markus 169: process_authentication_challenge1(SocketEntry *e)
1.1 deraadt 170: {
1.33 markus 171: Key *key, *private;
172: BIGNUM *challenge;
173: int i, len;
1.21 markus 174: Buffer msg;
175: MD5_CTX md;
1.45 markus 176: u_char buf[32], mdbuf[16], session_id[16];
177: u_int response_type;
1.21 markus 178:
179: buffer_init(&msg);
1.39 markus 180: key = key_new(KEY_RSA1);
1.21 markus 181: challenge = BN_new();
1.33 markus 182:
183: buffer_get_int(&e->input); /* ignored */
184: buffer_get_bignum(&e->input, key->rsa->e);
185: buffer_get_bignum(&e->input, key->rsa->n);
1.21 markus 186: buffer_get_bignum(&e->input, challenge);
187:
1.33 markus 188: /* Only protocol 1.1 is supported */
189: if (buffer_len(&e->input) == 0)
190: goto failure;
191: buffer_get(&e->input, (char *) session_id, 16);
192: response_type = buffer_get_int(&e->input);
193: if (response_type != 1)
194: goto failure;
195:
196: private = lookup_private_key(key, NULL, 1);
197: if (private != NULL) {
198: /* Decrypt the challenge using the private key. */
1.49 markus 199: if (rsa_private_decrypt(challenge, challenge, private->rsa) <= 0)
200: goto failure;
1.33 markus 201:
202: /* The response is MD5 of decrypted challenge plus session id. */
203: len = BN_num_bytes(challenge);
204: if (len <= 0 || len > 32) {
205: log("process_authentication_challenge: bad challenge length %d", len);
206: goto failure;
207: }
208: memset(buf, 0, 32);
209: BN_bn2bin(challenge, buf + 32 - len);
210: MD5_Init(&md);
211: MD5_Update(&md, buf, 32);
212: MD5_Update(&md, session_id, 16);
213: MD5_Final(mdbuf, &md);
214:
215: /* Send the response. */
216: buffer_put_char(&msg, SSH_AGENT_RSA_RESPONSE);
217: for (i = 0; i < 16; i++)
218: buffer_put_char(&msg, mdbuf[i]);
219: goto send;
220: }
1.21 markus 221:
1.33 markus 222: failure:
223: /* Unknown identity or protocol error. Send failure. */
1.21 markus 224: buffer_put_char(&msg, SSH_AGENT_FAILURE);
225: send:
226: buffer_put_int(&e->output, buffer_len(&msg));
1.33 markus 227: buffer_append(&e->output, buffer_ptr(&msg), buffer_len(&msg));
228: key_free(key);
229: BN_clear_free(challenge);
230: buffer_free(&msg);
231: }
232:
233: /* ssh2 only */
1.54.2.1! jason 234: static void
1.33 markus 235: process_sign_request2(SocketEntry *e)
236: {
237: extern int datafellows;
238: Key *key, *private;
1.45 markus 239: u_char *blob, *data, *signature = NULL;
240: u_int blen, dlen, slen = 0;
1.37 markus 241: int flags;
1.33 markus 242: Buffer msg;
243: int ok = -1;
244:
245: datafellows = 0;
1.43 markus 246:
1.33 markus 247: blob = buffer_get_string(&e->input, &blen);
248: data = buffer_get_string(&e->input, &dlen);
1.37 markus 249:
250: flags = buffer_get_int(&e->input);
251: if (flags & SSH_AGENT_OLD_SIGNATURE)
252: datafellows = SSH_BUG_SIGBLOB;
1.33 markus 253:
1.39 markus 254: key = key_from_blob(blob, blen);
1.33 markus 255: if (key != NULL) {
256: private = lookup_private_key(key, NULL, 2);
257: if (private != NULL)
1.39 markus 258: ok = key_sign(private, &signature, &slen, data, dlen);
1.33 markus 259: }
260: key_free(key);
261: buffer_init(&msg);
262: if (ok == 0) {
263: buffer_put_char(&msg, SSH2_AGENT_SIGN_RESPONSE);
264: buffer_put_string(&msg, signature, slen);
265: } else {
266: buffer_put_char(&msg, SSH_AGENT_FAILURE);
267: }
268: buffer_put_int(&e->output, buffer_len(&msg));
1.21 markus 269: buffer_append(&e->output, buffer_ptr(&msg),
1.33 markus 270: buffer_len(&msg));
1.21 markus 271: buffer_free(&msg);
1.33 markus 272: xfree(data);
273: xfree(blob);
274: if (signature != NULL)
275: xfree(signature);
1.1 deraadt 276: }
277:
1.33 markus 278: /* shared */
1.54.2.1! jason 279: static void
1.33 markus 280: process_remove_identity(SocketEntry *e, int version)
1.1 deraadt 281: {
1.33 markus 282: Key *key = NULL, *private;
1.45 markus 283: u_char *blob;
284: u_int blen;
285: u_int bits;
1.33 markus 286: int success = 0;
1.21 markus 287:
1.33 markus 288: switch(version){
289: case 1:
1.39 markus 290: key = key_new(KEY_RSA1);
1.33 markus 291: bits = buffer_get_int(&e->input);
292: buffer_get_bignum(&e->input, key->rsa->e);
293: buffer_get_bignum(&e->input, key->rsa->n);
294:
295: if (bits != key_size(key))
296: log("Warning: identity keysize mismatch: actual %d, announced %d",
1.46 markus 297: key_size(key), bits);
1.33 markus 298: break;
299: case 2:
300: blob = buffer_get_string(&e->input, &blen);
1.39 markus 301: key = key_from_blob(blob, blen);
1.33 markus 302: xfree(blob);
303: break;
304: }
305: if (key != NULL) {
306: int idx;
307: private = lookup_private_key(key, &idx, version);
308: if (private != NULL) {
1.23 markus 309: /*
310: * We have this key. Free the old key. Since we
311: * don\'t want to leave empty slots in the middle of
1.40 markus 312: * the array, we actually free the key there and move
313: * all the entries between the empty slot and the end
314: * of the array.
1.23 markus 315: */
1.33 markus 316: Idtab *tab = idtab_lookup(version);
317: key_free(tab->identities[idx].key);
318: xfree(tab->identities[idx].comment);
1.38 markus 319: if (tab->nentries < 1)
320: fatal("process_remove_identity: "
321: "internal error: tab->nentries %d",
322: tab->nentries);
1.40 markus 323: if (idx != tab->nentries - 1) {
324: int i;
325: for (i = idx; i < tab->nentries - 1; i++)
326: tab->identities[i] = tab->identities[i+1];
327: }
328: tab->identities[tab->nentries - 1].key = NULL;
329: tab->identities[tab->nentries - 1].comment = NULL;
1.33 markus 330: tab->nentries--;
331: success = 1;
1.21 markus 332: }
1.33 markus 333: key_free(key);
334: }
1.1 deraadt 335: buffer_put_int(&e->output, 1);
1.33 markus 336: buffer_put_char(&e->output,
337: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 338: }
339:
1.54.2.1! jason 340: static void
1.33 markus 341: process_remove_all_identities(SocketEntry *e, int version)
1.1 deraadt 342: {
1.45 markus 343: u_int i;
1.33 markus 344: Idtab *tab = idtab_lookup(version);
1.21 markus 345:
346: /* Loop over all identities and clear the keys. */
1.33 markus 347: for (i = 0; i < tab->nentries; i++) {
348: key_free(tab->identities[i].key);
349: xfree(tab->identities[i].comment);
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);
390: switch(type) {
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;
423: if (lookup_private_key(k, NULL, version) == NULL) {
424: if (tab->nentries == 0)
425: tab->identities = xmalloc(sizeof(Identity));
426: else
427: tab->identities = xrealloc(tab->identities,
428: (tab->nentries + 1) * sizeof(Identity));
429: tab->identities[tab->nentries].key = k;
430: tab->identities[tab->nentries].comment = comment;
431: /* Increment the number of identities. */
432: tab->nentries++;
433: } else {
434: key_free(k);
435: xfree(comment);
436: }
437: send:
1.1 deraadt 438: buffer_put_int(&e->output, 1);
1.33 markus 439: buffer_put_char(&e->output,
440: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
1.1 deraadt 441: }
442:
1.54.2.1! jason 443:
! 444: #ifdef SMARTCARD
! 445: static void
! 446: process_add_smartcard_key (SocketEntry *e)
! 447: {
! 448: Idtab *tab;
! 449: Key *n = NULL, *k = NULL;
! 450: char *sc_reader_id = NULL;
! 451: int success = 0;
! 452:
! 453: sc_reader_id = buffer_get_string(&e->input, NULL);
! 454: k = sc_get_key(sc_reader_id);
! 455: xfree(sc_reader_id);
! 456:
! 457: if (k == NULL) {
! 458: error("sc_get_pubkey failed");
! 459: goto send;
! 460: }
! 461: success = 1;
! 462:
! 463: tab = idtab_lookup(1);
! 464: k->type = KEY_RSA1;
! 465: if (lookup_private_key(k, NULL, 1) == NULL) {
! 466: if (tab->nentries == 0)
! 467: tab->identities = xmalloc(sizeof(Identity));
! 468: else
! 469: tab->identities = xrealloc(tab->identities,
! 470: (tab->nentries + 1) * sizeof(Identity));
! 471: n = key_new(KEY_RSA1);
! 472: BN_copy(n->rsa->n, k->rsa->n);
! 473: BN_copy(n->rsa->e, k->rsa->e);
! 474: RSA_set_method(n->rsa, sc_get_engine());
! 475: tab->identities[tab->nentries].key = n;
! 476: tab->identities[tab->nentries].comment =
! 477: xstrdup("rsa1 smartcard");
! 478: tab->nentries++;
! 479: }
! 480: k->type = KEY_RSA;
! 481: tab = idtab_lookup(2);
! 482: if (lookup_private_key(k, NULL, 2) == NULL) {
! 483: if (tab->nentries == 0)
! 484: tab->identities = xmalloc(sizeof(Identity));
! 485: else
! 486: tab->identities = xrealloc(tab->identities,
! 487: (tab->nentries + 1) * sizeof(Identity));
! 488: n = key_new(KEY_RSA);
! 489: BN_copy(n->rsa->n, k->rsa->n);
! 490: BN_copy(n->rsa->e, k->rsa->e);
! 491: RSA_set_method(n->rsa, sc_get_engine());
! 492: tab->identities[tab->nentries].key = n;
! 493: tab->identities[tab->nentries].comment =
! 494: xstrdup("rsa smartcard");
! 495: tab->nentries++;
! 496: }
! 497: key_free(k);
! 498: send:
! 499: buffer_put_int(&e->output, 1);
! 500: buffer_put_char(&e->output,
! 501: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
! 502: }
! 503:
! 504: static void
! 505: process_remove_smartcard_key(SocketEntry *e)
! 506: {
! 507: Key *k = NULL, *private;
! 508: int idx;
! 509: int success = 0;
! 510: char *sc_reader_id = NULL;
! 511:
! 512: sc_reader_id = buffer_get_string(&e->input, NULL);
! 513: k = sc_get_key(sc_reader_id);
! 514: xfree(sc_reader_id);
! 515:
! 516: if (k == NULL) {
! 517: error("sc_get_pubkey failed");
! 518: } else {
! 519: k->type = KEY_RSA1;
! 520: private = lookup_private_key(k, &idx, 1);
! 521: if (private != NULL) {
! 522: Idtab *tab = idtab_lookup(1);
! 523: key_free(tab->identities[idx].key);
! 524: xfree(tab->identities[idx].comment);
! 525: if (idx != tab->nentries)
! 526: tab->identities[idx] = tab->identities[tab->nentries];
! 527: tab->nentries--;
! 528: success = 1;
! 529: }
! 530: k->type = KEY_RSA;
! 531: private = lookup_private_key(k, &idx, 2);
! 532: if (private != NULL) {
! 533: Idtab *tab = idtab_lookup(2);
! 534: key_free(tab->identities[idx].key);
! 535: xfree(tab->identities[idx].comment);
! 536: if (idx != tab->nentries)
! 537: tab->identities[idx] = tab->identities[tab->nentries];
! 538: tab->nentries--;
! 539: success = 1;
! 540: }
! 541: key_free(k);
! 542: }
! 543:
! 544: buffer_put_int(&e->output, 1);
! 545: buffer_put_char(&e->output,
! 546: success ? SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE);
! 547: }
! 548: #endif /* SMARTCARD */
! 549:
1.33 markus 550: /* dispatch incoming messages */
551:
1.54.2.1! jason 552: static void
1.2 provos 553: process_message(SocketEntry *e)
1.1 deraadt 554: {
1.45 markus 555: u_int msg_len;
556: u_int type;
557: u_char *cp;
1.21 markus 558: if (buffer_len(&e->input) < 5)
559: return; /* Incomplete message. */
1.45 markus 560: cp = (u_char *) buffer_ptr(&e->input);
1.21 markus 561: msg_len = GET_32BIT(cp);
562: if (msg_len > 256 * 1024) {
563: shutdown(e->fd, SHUT_RDWR);
564: close(e->fd);
565: e->type = AUTH_UNUSED;
566: return;
567: }
568: if (buffer_len(&e->input) < msg_len + 4)
569: return;
570: buffer_consume(&e->input, 4);
571: type = buffer_get_char(&e->input);
572:
1.54.2.1! jason 573: debug("type %d", type);
1.21 markus 574: switch (type) {
1.33 markus 575: /* ssh1 */
576: case SSH_AGENTC_RSA_CHALLENGE:
577: process_authentication_challenge1(e);
578: break;
1.21 markus 579: case SSH_AGENTC_REQUEST_RSA_IDENTITIES:
1.33 markus 580: process_request_identities(e, 1);
1.21 markus 581: break;
582: case SSH_AGENTC_ADD_RSA_IDENTITY:
1.33 markus 583: process_add_identity(e, 1);
1.21 markus 584: break;
585: case SSH_AGENTC_REMOVE_RSA_IDENTITY:
1.33 markus 586: process_remove_identity(e, 1);
1.21 markus 587: break;
588: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.33 markus 589: process_remove_all_identities(e, 1);
590: break;
591: /* ssh2 */
592: case SSH2_AGENTC_SIGN_REQUEST:
593: process_sign_request2(e);
594: break;
595: case SSH2_AGENTC_REQUEST_IDENTITIES:
596: process_request_identities(e, 2);
597: break;
598: case SSH2_AGENTC_ADD_IDENTITY:
599: process_add_identity(e, 2);
600: break;
601: case SSH2_AGENTC_REMOVE_IDENTITY:
602: process_remove_identity(e, 2);
603: break;
604: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
605: process_remove_all_identities(e, 2);
1.21 markus 606: break;
1.54.2.1! jason 607: #ifdef SMARTCARD
! 608: case SSH_AGENTC_ADD_SMARTCARD_KEY:
! 609: process_add_smartcard_key(e);
! 610: break;
! 611: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
! 612: process_remove_smartcard_key(e);
! 613: break;
! 614: #endif /* SMARTCARD */
1.21 markus 615: default:
616: /* Unknown message. Respond with failure. */
617: error("Unknown message %d", type);
618: buffer_clear(&e->input);
619: buffer_put_int(&e->output, 1);
620: buffer_put_char(&e->output, SSH_AGENT_FAILURE);
621: break;
622: }
1.1 deraadt 623: }
624:
1.54.2.1! jason 625: static void
1.2 provos 626: new_socket(int type, int fd)
1.1 deraadt 627: {
1.45 markus 628: u_int i, old_alloc;
1.21 markus 629: if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
630: error("fcntl O_NONBLOCK: %s", strerror(errno));
631:
632: if (fd > max_fd)
633: max_fd = fd;
634:
635: for (i = 0; i < sockets_alloc; i++)
636: if (sockets[i].type == AUTH_UNUSED) {
637: sockets[i].fd = fd;
638: sockets[i].type = type;
639: buffer_init(&sockets[i].input);
640: buffer_init(&sockets[i].output);
641: return;
642: }
643: old_alloc = sockets_alloc;
644: sockets_alloc += 10;
645: if (sockets)
646: sockets = xrealloc(sockets, sockets_alloc * sizeof(sockets[0]));
647: else
648: sockets = xmalloc(sockets_alloc * sizeof(sockets[0]));
649: for (i = old_alloc; i < sockets_alloc; i++)
650: sockets[i].type = AUTH_UNUSED;
651: sockets[old_alloc].type = type;
652: sockets[old_alloc].fd = fd;
653: buffer_init(&sockets[old_alloc].input);
654: buffer_init(&sockets[old_alloc].output);
1.1 deraadt 655: }
656:
1.54.2.1! jason 657: static int
! 658: prepare_select(fd_set **fdrp, fd_set **fdwp, int *fdl, int *nallocp)
1.1 deraadt 659: {
1.46 markus 660: u_int i, sz;
661: int n = 0;
662:
663: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 664: switch (sockets[i].type) {
665: case AUTH_SOCKET:
666: case AUTH_CONNECTION:
1.46 markus 667: n = MAX(n, sockets[i].fd);
1.21 markus 668: break;
669: case AUTH_UNUSED:
670: break;
671: default:
672: fatal("Unknown socket type %d", sockets[i].type);
673: break;
674: }
1.46 markus 675: }
676:
677: sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1.54.2.1! jason 678: if (*fdrp == NULL || sz > *nallocp) {
1.46 markus 679: if (*fdrp)
1.54 stevesk 680: xfree(*fdrp);
1.46 markus 681: if (*fdwp)
1.54 stevesk 682: xfree(*fdwp);
1.46 markus 683: *fdrp = xmalloc(sz);
684: *fdwp = xmalloc(sz);
1.54.2.1! jason 685: *nallocp = sz;
1.46 markus 686: }
1.54.2.1! jason 687: if (n < *fdl)
! 688: debug("XXX shrink: %d < %d", n, *fdl);
! 689: *fdl = n;
1.46 markus 690: memset(*fdrp, 0, sz);
691: memset(*fdwp, 0, sz);
692:
693: for (i = 0; i < sockets_alloc; i++) {
694: switch (sockets[i].type) {
695: case AUTH_SOCKET:
696: case AUTH_CONNECTION:
697: FD_SET(sockets[i].fd, *fdrp);
698: if (buffer_len(&sockets[i].output) > 0)
699: FD_SET(sockets[i].fd, *fdwp);
700: break;
701: default:
702: break;
703: }
704: }
705: return (1);
1.21 markus 706: }
707:
1.54.2.1! jason 708: static void
1.21 markus 709: after_select(fd_set *readset, fd_set *writeset)
710: {
1.45 markus 711: u_int i;
1.21 markus 712: int len, sock;
1.26 markus 713: socklen_t slen;
1.21 markus 714: char buf[1024];
715: struct sockaddr_un sunaddr;
716:
717: for (i = 0; i < sockets_alloc; i++)
718: switch (sockets[i].type) {
719: case AUTH_UNUSED:
720: break;
721: case AUTH_SOCKET:
722: if (FD_ISSET(sockets[i].fd, readset)) {
1.26 markus 723: slen = sizeof(sunaddr);
1.46 markus 724: sock = accept(sockets[i].fd,
725: (struct sockaddr *) &sunaddr, &slen);
1.21 markus 726: if (sock < 0) {
727: perror("accept from AUTH_SOCKET");
728: break;
729: }
730: new_socket(AUTH_CONNECTION, sock);
731: }
732: break;
733: case AUTH_CONNECTION:
734: if (buffer_len(&sockets[i].output) > 0 &&
735: FD_ISSET(sockets[i].fd, writeset)) {
1.52 deraadt 736: do {
737: len = write(sockets[i].fd,
738: buffer_ptr(&sockets[i].output),
739: buffer_len(&sockets[i].output));
740: if (len == -1 && (errno == EAGAIN ||
741: errno == EINTR))
742: continue;
743: break;
744: } while (1);
1.21 markus 745: if (len <= 0) {
746: shutdown(sockets[i].fd, SHUT_RDWR);
747: close(sockets[i].fd);
748: sockets[i].type = AUTH_UNUSED;
1.30 djm 749: buffer_free(&sockets[i].input);
750: buffer_free(&sockets[i].output);
1.21 markus 751: break;
752: }
753: buffer_consume(&sockets[i].output, len);
754: }
755: if (FD_ISSET(sockets[i].fd, readset)) {
1.52 deraadt 756: do {
757: len = read(sockets[i].fd, buf, sizeof(buf));
758: if (len == -1 && (errno == EAGAIN ||
759: errno == EINTR))
760: continue;
761: break;
762: } while (1);
1.21 markus 763: if (len <= 0) {
764: shutdown(sockets[i].fd, SHUT_RDWR);
765: close(sockets[i].fd);
766: sockets[i].type = AUTH_UNUSED;
1.30 djm 767: buffer_free(&sockets[i].input);
768: buffer_free(&sockets[i].output);
1.21 markus 769: break;
770: }
771: buffer_append(&sockets[i].input, buf, len);
772: process_message(&sockets[i]);
773: }
774: break;
775: default:
776: fatal("Unknown type %d", sockets[i].type);
777: }
1.1 deraadt 778: }
779:
1.54.2.1! jason 780: static void
1.15 markus 781: cleanup_socket(void)
782: {
1.48 deraadt 783: if (socket_name[0])
784: unlink(socket_name);
785: if (socket_dir[0])
786: rmdir(socket_dir);
1.10 markus 787: }
788:
1.54.2.1! jason 789: static void
1.15 markus 790: cleanup_exit(int i)
791: {
1.21 markus 792: cleanup_socket();
793: exit(i);
1.15 markus 794: }
795:
1.54.2.1! jason 796: static void
1.48 deraadt 797: cleanup_handler(int sig)
798: {
799: cleanup_socket();
800: _exit(2);
801: }
802:
1.54.2.1! jason 803: static void
! 804: check_parent_exists(int sig)
! 805: {
! 806: int save_errno = errno;
! 807:
! 808: if (parent_pid != -1 && kill(parent_pid, 0) < 0) {
! 809: /* printf("Parent has died - Authentication agent exiting.\n"); */
! 810: cleanup_handler(sig); /* safe */
! 811: }
! 812: signal(SIGALRM, check_parent_exists);
! 813: alarm(10);
! 814: errno = save_errno;
! 815: }
! 816:
! 817: static void
1.50 itojun 818: usage(void)
1.15 markus 819: {
1.54.2.1! jason 820: fprintf(stderr, "Usage: %s [options] [command [args ...]]\n",
1.46 markus 821: __progname);
1.54.2.1! jason 822: fprintf(stderr, "Options:\n");
! 823: fprintf(stderr, " -c Generate C-shell commands on stdout.\n");
! 824: fprintf(stderr, " -s Generate Bourne shell commands on stdout.\n");
! 825: fprintf(stderr, " -k Kill the current agent.\n");
! 826: fprintf(stderr, " -d Debug mode.\n");
1.21 markus 827: exit(1);
1.15 markus 828: }
829:
1.2 provos 830: int
831: main(int ac, char **av)
1.1 deraadt 832: {
1.54.2.1! jason 833: int sock, c_flag = 0, d_flag = 0, k_flag = 0, s_flag = 0, ch, nalloc;
1.21 markus 834: struct sockaddr_un sunaddr;
1.41 markus 835: struct rlimit rlim;
1.21 markus 836: pid_t pid;
837: char *shell, *format, *pidstr, pidstrbuf[1 + 3 * sizeof pid];
1.43 markus 838: extern int optind;
1.46 markus 839: fd_set *readsetp = NULL, *writesetp = NULL;
1.53 markus 840:
841: SSLeay_add_all_algorithms();
1.21 markus 842:
1.54.2.1! jason 843: while ((ch = getopt(ac, av, "cdks")) != -1) {
1.21 markus 844: switch (ch) {
845: case 'c':
846: if (s_flag)
847: usage();
848: c_flag++;
849: break;
850: case 'k':
851: k_flag++;
852: break;
853: case 's':
854: if (c_flag)
855: usage();
856: s_flag++;
857: break;
1.54.2.1! jason 858: case 'd':
! 859: if (d_flag)
! 860: usage();
! 861: d_flag++;
! 862: break;
1.21 markus 863: default:
864: usage();
865: }
866: }
867: ac -= optind;
868: av += optind;
869:
1.54.2.1! jason 870: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag))
1.21 markus 871: usage();
872:
1.54.2.1! jason 873: if (ac == 0 && !c_flag && !k_flag && !s_flag && !d_flag) {
1.21 markus 874: shell = getenv("SHELL");
875: if (shell != NULL && strncmp(shell + strlen(shell) - 3, "csh", 3) == 0)
876: c_flag = 1;
877: }
878: if (k_flag) {
879: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
880: if (pidstr == NULL) {
881: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 882: SSH_AGENTPID_ENV_NAME);
1.21 markus 883: exit(1);
884: }
885: pid = atoi(pidstr);
1.46 markus 886: if (pid < 1) {
1.21 markus 887: fprintf(stderr, "%s=\"%s\", which is not a good PID\n",
1.46 markus 888: SSH_AGENTPID_ENV_NAME, pidstr);
1.21 markus 889: exit(1);
890: }
891: if (kill(pid, SIGTERM) == -1) {
892: perror("kill");
893: exit(1);
894: }
895: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
896: printf(format, SSH_AUTHSOCKET_ENV_NAME);
897: printf(format, SSH_AGENTPID_ENV_NAME);
898: printf("echo Agent pid %d killed;\n", pid);
899: exit(0);
900: }
901: parent_pid = getpid();
902:
903: /* Create private directory for agent socket */
904: strlcpy(socket_dir, "/tmp/ssh-XXXXXXXX", sizeof socket_dir);
905: if (mkdtemp(socket_dir) == NULL) {
906: perror("mkdtemp: private socket dir");
907: exit(1);
908: }
909: snprintf(socket_name, sizeof socket_name, "%s/agent.%d", socket_dir,
1.46 markus 910: parent_pid);
1.21 markus 911:
1.23 markus 912: /*
913: * Create socket early so it will exist before command gets run from
914: * the parent.
915: */
1.21 markus 916: sock = socket(AF_UNIX, SOCK_STREAM, 0);
917: if (sock < 0) {
918: perror("socket");
919: cleanup_exit(1);
920: }
921: memset(&sunaddr, 0, sizeof(sunaddr));
922: sunaddr.sun_family = AF_UNIX;
923: strlcpy(sunaddr.sun_path, socket_name, sizeof(sunaddr.sun_path));
924: if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0) {
925: perror("bind");
926: cleanup_exit(1);
927: }
928: if (listen(sock, 5) < 0) {
929: perror("listen");
930: cleanup_exit(1);
931: }
1.46 markus 932:
1.23 markus 933: /*
934: * Fork, and have the parent execute the command, if any, or present
935: * the socket data. The child continues as the authentication agent.
936: */
1.54.2.1! jason 937: if (d_flag) {
! 938: log_init(__progname, SYSLOG_LEVEL_DEBUG1, SYSLOG_FACILITY_AUTH, 1);
! 939: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
! 940: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
! 941: SSH_AUTHSOCKET_ENV_NAME);
! 942: printf("echo Agent pid %d;\n", parent_pid);
! 943: goto skip;
! 944: }
1.21 markus 945: pid = fork();
946: if (pid == -1) {
947: perror("fork");
948: exit(1);
949: }
950: if (pid != 0) { /* Parent - execute the given command. */
951: close(sock);
952: snprintf(pidstrbuf, sizeof pidstrbuf, "%d", pid);
953: if (ac == 0) {
954: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
955: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 956: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 957: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 958: SSH_AGENTPID_ENV_NAME);
1.21 markus 959: printf("echo Agent pid %d;\n", pid);
960: exit(0);
961: }
1.36 deraadt 962: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
963: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
964: perror("setenv");
965: exit(1);
966: }
1.21 markus 967: execvp(av[0], av);
968: perror(av[0]);
969: exit(1);
970: }
1.54.2.1! jason 971:
! 972: if (setsid() == -1) {
! 973: perror("setsid");
! 974: cleanup_exit(1);
! 975: }
! 976:
! 977: (void)chdir("/");
1.21 markus 978: close(0);
979: close(1);
980: close(2);
981:
1.41 markus 982: /* deny core dumps, since memory contains unencrypted private keys */
983: rlim.rlim_cur = rlim.rlim_max = 0;
984: if (setrlimit(RLIMIT_CORE, &rlim) < 0) {
985: perror("setrlimit rlimit_core failed");
986: cleanup_exit(1);
987: }
1.54.2.1! jason 988:
! 989: skip:
1.21 markus 990: if (atexit(cleanup_socket) < 0) {
991: perror("atexit");
992: cleanup_exit(1);
993: }
994: new_socket(AUTH_SOCKET, sock);
995: if (ac > 0) {
996: signal(SIGALRM, check_parent_exists);
997: alarm(10);
998: }
1.33 markus 999: idtab_init();
1.54.2.1! jason 1000: if (!d_flag)
! 1001: signal(SIGINT, SIG_IGN);
1.21 markus 1002: signal(SIGPIPE, SIG_IGN);
1.48 deraadt 1003: signal(SIGHUP, cleanup_handler);
1004: signal(SIGTERM, cleanup_handler);
1.54.2.1! jason 1005: nalloc = 0;
! 1006:
1.21 markus 1007: while (1) {
1.54.2.1! jason 1008: prepare_select(&readsetp, &writesetp, &max_fd, &nalloc);
1.46 markus 1009: if (select(max_fd + 1, readsetp, writesetp, NULL, NULL) < 0) {
1.21 markus 1010: if (errno == EINTR)
1011: continue;
1012: exit(1);
1013: }
1.46 markus 1014: after_select(readsetp, writesetp);
1.15 markus 1015: }
1.21 markus 1016: /* NOTREACHED */
1.1 deraadt 1017: }
![[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