Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.304
1.304 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.303 2023/12/18 14:48:08 djm Exp $ */
1.1 deraadt 2: /*
1.22 deraadt 3: * Author: Tatu Ylonen <ylo@cs.hut.fi>
4: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5: * All rights reserved
6: * The authentication agent program.
1.33 markus 7: *
1.35 deraadt 8: * As far as I am concerned, the code I have written for this software
9: * can be used freely for any purpose. Any derived versions of this
10: * software must be clearly marked as such, and if the derived work is
11: * incompatible with the protocol description in the RFC file, it must be
12: * called by a name other than "ssh" or "Secure Shell".
13: *
1.56 markus 14: * Copyright (c) 2000, 2001 Markus Friedl. All rights reserved.
1.35 deraadt 15: *
16: * Redistribution and use in source and binary forms, with or without
17: * modification, are permitted provided that the following conditions
18: * are met:
19: * 1. Redistributions of source code must retain the above copyright
20: * notice, this list of conditions and the following disclaimer.
21: * 2. Redistributions in binary form must reproduce the above copyright
22: * notice, this list of conditions and the following disclaimer in the
23: * documentation and/or other materials provided with the distribution.
24: *
25: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.22 deraadt 35: */
1.1 deraadt 36:
1.151 deraadt 37: #include <sys/types.h>
1.153 djm 38: #include <sys/time.h>
1.78 provos 39: #include <sys/queue.h>
1.127 stevesk 40: #include <sys/resource.h>
1.141 stevesk 41: #include <sys/socket.h>
1.189 djm 42: #include <sys/stat.h>
1.128 stevesk 43: #include <sys/un.h>
1.238 djm 44: #include <sys/wait.h>
1.126 stevesk 45:
1.185 markus 46: #ifdef WITH_OPENSSL
1.146 stevesk 47: #include <openssl/evp.h>
1.185 markus 48: #endif
1.146 stevesk 49:
1.143 stevesk 50: #include <errno.h>
1.142 stevesk 51: #include <fcntl.h>
1.126 stevesk 52: #include <paths.h>
1.223 djm 53: #include <poll.h>
1.129 stevesk 54: #include <signal.h>
1.149 stevesk 55: #include <stdlib.h>
1.150 stevesk 56: #include <stdio.h>
1.146 stevesk 57: #include <string.h>
1.248 naddy 58: #include <stdarg.h>
1.196 deraadt 59: #include <limits.h>
1.145 stevesk 60: #include <time.h>
1.144 stevesk 61: #include <unistd.h>
1.203 dtucker 62: #include <util.h>
1.194 markus 63:
1.151 deraadt 64: #include "xmalloc.h"
1.1 deraadt 65: #include "ssh.h"
1.258 djm 66: #include "ssh2.h"
1.194 markus 67: #include "sshbuf.h"
68: #include "sshkey.h"
1.32 markus 69: #include "authfd.h"
1.47 markus 70: #include "log.h"
1.107 markus 71: #include "misc.h"
1.182 markus 72: #include "digest.h"
1.194 markus 73: #include "ssherr.h"
1.215 djm 74: #include "match.h"
1.238 djm 75: #include "msg.h"
76: #include "pathnames.h"
1.163 markus 77: #include "ssh-pkcs11.h"
1.251 djm 78: #include "sk-api.h"
1.281 djm 79: #include "myproposal.h"
1.59 markus 80:
1.262 djm 81: #ifndef DEFAULT_ALLOWED_PROVIDERS
82: # define DEFAULT_ALLOWED_PROVIDERS "/usr/lib*/*,/usr/local/lib*/*"
1.215 djm 83: #endif
84:
1.223 djm 85: /* Maximum accepted message length */
1.280 djm 86: #define AGENT_MAX_LEN (256*1024)
1.233 djm 87: /* Maximum bytes to read from client socket */
1.280 djm 88: #define AGENT_RBUF_LEN (4096)
89: /* Maximum number of recorded session IDs/hostkeys per connection */
90: #define AGENT_MAX_SESSION_IDS 16
91: /* Maximum size of session ID */
92: #define AGENT_MAX_SID_LEN 128
1.281 djm 93: /* Maximum number of destination constraints to accept on a key */
94: #define AGENT_MAX_DEST_CONSTRAINTS 1024
1.302 djm 95: /* Maximum number of associated certificate constraints to accept on a key */
96: #define AGENT_MAX_EXT_CERTS 1024
1.280 djm 97:
98: /* XXX store hostkey_sid in a refcounted tree */
1.223 djm 99:
1.73 stevesk 100: typedef enum {
1.275 djm 101: AUTH_UNUSED = 0,
102: AUTH_SOCKET = 1,
103: AUTH_CONNECTION = 2,
1.73 stevesk 104: } sock_type;
105:
1.280 djm 106: struct hostkey_sid {
107: struct sshkey *key;
108: struct sshbuf *sid;
109: int forwarded;
110: };
111:
1.274 djm 112: typedef struct socket_entry {
1.21 markus 113: int fd;
1.73 stevesk 114: sock_type type;
1.194 markus 115: struct sshbuf *input;
116: struct sshbuf *output;
117: struct sshbuf *request;
1.280 djm 118: size_t nsession_ids;
119: struct hostkey_sid *session_ids;
1.303 djm 120: int session_bind_attempted;
1.1 deraadt 121: } SocketEntry;
122:
1.45 markus 123: u_int sockets_alloc = 0;
1.1 deraadt 124: SocketEntry *sockets = NULL;
125:
1.78 provos 126: typedef struct identity {
127: TAILQ_ENTRY(identity) next;
1.194 markus 128: struct sshkey *key;
1.21 markus 129: char *comment;
1.163 markus 130: char *provider;
1.174 dtucker 131: time_t death;
1.107 markus 132: u_int confirm;
1.238 djm 133: char *sk_provider;
1.281 djm 134: struct dest_constraint *dest_constraints;
135: size_t ndest_constraints;
1.1 deraadt 136: } Identity;
137:
1.221 djm 138: struct idtable {
1.33 markus 139: int nentries;
1.78 provos 140: TAILQ_HEAD(idqueue, identity) idlist;
1.221 djm 141: };
1.33 markus 142:
1.221 djm 143: /* private key table */
144: struct idtable *idtab;
1.1 deraadt 145:
146: int max_fd = 0;
147:
1.11 markus 148: /* pid of shell == parent of agent */
1.29 deraadt 149: pid_t parent_pid = -1;
1.176 dtucker 150: time_t parent_alive_interval = 0;
1.10 markus 151:
1.187 djm 152: /* pid of process for which cleanup_socket is applicable */
153: pid_t cleanup_pid = 0;
154:
1.10 markus 155: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 156: char socket_name[PATH_MAX];
157: char socket_dir[PATH_MAX];
1.10 markus 158:
1.260 djm 159: /* Pattern-list of allowed PKCS#11/Security key paths */
160: static char *allowed_providers;
1.215 djm 161:
1.300 djm 162: /*
163: * Allows PKCS11 providers or SK keys that use non-internal providers to
164: * be added over a remote connection (identified by session-bind@openssh.com).
165: */
166: static int remote_add_provider;
167:
1.88 markus 168: /* locking */
1.203 dtucker 169: #define LOCK_SIZE 32
170: #define LOCK_SALT_SIZE 16
171: #define LOCK_ROUNDS 1
1.88 markus 172: int locked = 0;
1.213 djm 173: u_char lock_pwhash[LOCK_SIZE];
174: u_char lock_salt[LOCK_SALT_SIZE];
1.88 markus 175:
1.20 markus 176: extern char *__progname;
177:
1.174 dtucker 178: /* Default lifetime in seconds (0 == forever) */
1.268 dtucker 179: static int lifetime = 0;
1.106 marc 180:
1.192 djm 181: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
182:
1.258 djm 183: /* Refuse signing of non-SSH messages for web-origin FIDO keys */
184: static int restrict_websafe = 1;
185:
1.55 itojun 186: static void
1.101 stevesk 187: close_socket(SocketEntry *e)
188: {
1.280 djm 189: size_t i;
190:
1.101 stevesk 191: close(e->fd);
1.194 markus 192: sshbuf_free(e->input);
193: sshbuf_free(e->output);
194: sshbuf_free(e->request);
1.280 djm 195: for (i = 0; i < e->nsession_ids; i++) {
196: sshkey_free(e->session_ids[i].key);
197: sshbuf_free(e->session_ids[i].sid);
198: }
199: free(e->session_ids);
1.269 djm 200: memset(e, '\0', sizeof(*e));
201: e->fd = -1;
202: e->type = AUTH_UNUSED;
1.101 stevesk 203: }
204:
205: static void
1.33 markus 206: idtab_init(void)
1.1 deraadt 207: {
1.221 djm 208: idtab = xcalloc(1, sizeof(*idtab));
209: TAILQ_INIT(&idtab->idlist);
210: idtab->nentries = 0;
1.33 markus 211: }
212:
1.89 markus 213: static void
1.281 djm 214: free_dest_constraint_hop(struct dest_constraint_hop *dch)
215: {
216: u_int i;
217:
218: if (dch == NULL)
219: return;
220: free(dch->user);
221: free(dch->hostname);
222: for (i = 0; i < dch->nkeys; i++)
223: sshkey_free(dch->keys[i]);
224: free(dch->keys);
225: free(dch->key_is_ca);
226: }
227:
228: static void
229: free_dest_constraints(struct dest_constraint *dcs, size_t ndcs)
230: {
231: size_t i;
232:
233: for (i = 0; i < ndcs; i++) {
234: free_dest_constraint_hop(&dcs[i].from);
235: free_dest_constraint_hop(&dcs[i].to);
236: }
237: free(dcs);
238: }
239:
240: static void
1.301 djm 241: dup_dest_constraint_hop(const struct dest_constraint_hop *dch,
242: struct dest_constraint_hop *out)
243: {
244: u_int i;
245: int r;
246:
247: out->user = dch->user == NULL ? NULL : xstrdup(dch->user);
248: out->hostname = dch->hostname == NULL ? NULL : xstrdup(dch->hostname);
249: out->is_ca = dch->is_ca;
250: out->nkeys = dch->nkeys;
251: out->keys = out->nkeys == 0 ? NULL :
252: xcalloc(out->nkeys, sizeof(*out->keys));
253: out->key_is_ca = out->nkeys == 0 ? NULL :
254: xcalloc(out->nkeys, sizeof(*out->key_is_ca));
255: for (i = 0; i < dch->nkeys; i++) {
256: if (dch->keys[i] != NULL &&
257: (r = sshkey_from_private(dch->keys[i],
258: &(out->keys[i]))) != 0)
259: fatal_fr(r, "copy key");
260: out->key_is_ca[i] = dch->key_is_ca[i];
261: }
262: }
263:
264: static struct dest_constraint *
265: dup_dest_constraints(const struct dest_constraint *dcs, size_t ndcs)
266: {
267: size_t i;
268: struct dest_constraint *ret;
269:
270: if (ndcs == 0)
271: return NULL;
272: ret = xcalloc(ndcs, sizeof(*ret));
273: for (i = 0; i < ndcs; i++) {
274: dup_dest_constraint_hop(&dcs[i].from, &ret[i].from);
275: dup_dest_constraint_hop(&dcs[i].to, &ret[i].to);
276: }
277: return ret;
278: }
279:
280: #ifdef DEBUG_CONSTRAINTS
281: static void
282: dump_dest_constraint_hop(const struct dest_constraint_hop *dch)
283: {
284: u_int i;
285: char *fp;
286:
287: debug_f("user %s hostname %s is_ca %d nkeys %u",
288: dch->user == NULL ? "(null)" : dch->user,
289: dch->hostname == NULL ? "(null)" : dch->hostname,
290: dch->is_ca, dch->nkeys);
291: for (i = 0; i < dch->nkeys; i++) {
292: fp = NULL;
293: if (dch->keys[i] != NULL &&
294: (fp = sshkey_fingerprint(dch->keys[i],
295: SSH_FP_HASH_DEFAULT, SSH_FP_DEFAULT)) == NULL)
296: fatal_f("fingerprint failed");
297: debug_f("key %u/%u: %s%s%s key_is_ca %d", i, dch->nkeys,
298: dch->keys[i] == NULL ? "" : sshkey_ssh_name(dch->keys[i]),
299: dch->keys[i] == NULL ? "" : " ",
300: dch->keys[i] == NULL ? "none" : fp,
301: dch->key_is_ca[i]);
302: free(fp);
303: }
304: }
305: #endif /* DEBUG_CONSTRAINTS */
306:
307: static void
308: dump_dest_constraints(const char *context,
309: const struct dest_constraint *dcs, size_t ndcs)
310: {
311: #ifdef DEBUG_CONSTRAINTS
312: size_t i;
313:
314: debug_f("%s: %zu constraints", context, ndcs);
315: for (i = 0; i < ndcs; i++) {
316: debug_f("constraint %zu / %zu: from: ", i, ndcs);
317: dump_dest_constraint_hop(&dcs[i].from);
318: debug_f("constraint %zu / %zu: to: ", i, ndcs);
319: dump_dest_constraint_hop(&dcs[i].to);
320: }
321: debug_f("done for %s", context);
322: #endif /* DEBUG_CONSTRAINTS */
323: }
324:
325: static void
1.89 markus 326: free_identity(Identity *id)
327: {
1.194 markus 328: sshkey_free(id->key);
1.173 djm 329: free(id->provider);
330: free(id->comment);
1.238 djm 331: free(id->sk_provider);
1.281 djm 332: free_dest_constraints(id->dest_constraints, id->ndest_constraints);
1.173 djm 333: free(id);
1.89 markus 334: }
335:
1.281 djm 336: /*
337: * Match 'key' against the key/CA list in a destination constraint hop
338: * Returns 0 on success or -1 otherwise.
339: */
340: static int
341: match_key_hop(const char *tag, const struct sshkey *key,
342: const struct dest_constraint_hop *dch)
343: {
344: const char *reason = NULL;
1.286 dtucker 345: const char *hostname = dch->hostname ? dch->hostname : "(ORIGIN)";
1.281 djm 346: u_int i;
347: char *fp;
348:
349: if (key == NULL)
350: return -1;
351: /* XXX logspam */
352: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
353: SSH_FP_DEFAULT)) == NULL)
354: fatal_f("fingerprint failed");
355: debug3_f("%s: entering hostname %s, requested key %s %s, %u keys avail",
1.286 dtucker 356: tag, hostname, sshkey_type(key), fp, dch->nkeys);
1.281 djm 357: free(fp);
358: for (i = 0; i < dch->nkeys; i++) {
359: if (dch->keys[i] == NULL)
360: return -1;
361: /* XXX logspam */
362: if ((fp = sshkey_fingerprint(dch->keys[i], SSH_FP_HASH_DEFAULT,
363: SSH_FP_DEFAULT)) == NULL)
364: fatal_f("fingerprint failed");
365: debug3_f("%s: key %u: %s%s %s", tag, i,
366: dch->key_is_ca[i] ? "CA " : "",
367: sshkey_type(dch->keys[i]), fp);
368: free(fp);
369: if (!sshkey_is_cert(key)) {
370: /* plain key */
371: if (dch->key_is_ca[i] ||
372: !sshkey_equal(key, dch->keys[i]))
373: continue;
374: return 0;
375: }
376: /* certificate */
377: if (!dch->key_is_ca[i])
378: continue;
379: if (key->cert == NULL || key->cert->signature_key == NULL)
380: return -1; /* shouldn't happen */
381: if (!sshkey_equal(key->cert->signature_key, dch->keys[i]))
382: continue;
1.286 dtucker 383: if (sshkey_cert_check_host(key, hostname, 1,
1.281 djm 384: SSH_ALLOWED_CA_SIGALGS, &reason) != 0) {
385: debug_f("cert %s / hostname %s rejected: %s",
1.286 dtucker 386: key->cert->key_id, hostname, reason);
1.281 djm 387: continue;
388: }
389: return 0;
390: }
391: return -1;
392: }
393:
394: /* Check destination constraints on an identity against the hostkey/user */
395: static int
396: permitted_by_dest_constraints(const struct sshkey *fromkey,
397: const struct sshkey *tokey, Identity *id, const char *user,
398: const char **hostnamep)
399: {
400: size_t i;
401: struct dest_constraint *d;
402:
403: if (hostnamep != NULL)
404: *hostnamep = NULL;
405: for (i = 0; i < id->ndest_constraints; i++) {
406: d = id->dest_constraints + i;
407: /* XXX remove logspam */
408: debug2_f("constraint %zu %s%s%s (%u keys) > %s%s%s (%u keys)",
409: i, d->from.user ? d->from.user : "",
410: d->from.user ? "@" : "",
411: d->from.hostname ? d->from.hostname : "(ORIGIN)",
412: d->from.nkeys,
413: d->to.user ? d->to.user : "", d->to.user ? "@" : "",
414: d->to.hostname ? d->to.hostname : "(ANY)", d->to.nkeys);
415:
416: /* Match 'from' key */
417: if (fromkey == NULL) {
418: /* We are matching the first hop */
419: if (d->from.hostname != NULL || d->from.nkeys != 0)
420: continue;
421: } else if (match_key_hop("from", fromkey, &d->from) != 0)
422: continue;
423:
424: /* Match 'to' key */
425: if (tokey != NULL && match_key_hop("to", tokey, &d->to) != 0)
426: continue;
427:
428: /* Match user if specified */
429: if (d->to.user != NULL && user != NULL &&
430: !match_pattern(user, d->to.user))
431: continue;
432:
433: /* successfully matched this constraint */
434: if (hostnamep != NULL)
435: *hostnamep = d->to.hostname;
436: debug2_f("allowed for hostname %s",
437: d->to.hostname == NULL ? "*" : d->to.hostname);
438: return 0;
439: }
440: /* no match */
441: debug2_f("%s identity \"%s\" not permitted for this destination",
442: sshkey_type(id->key), id->comment);
443: return -1;
444: }
445:
446: /*
447: * Check whether hostkeys on a SocketEntry and the optionally specified user
448: * are permitted by the destination constraints on the Identity.
449: * Returns 0 on success or -1 otherwise.
450: */
451: static int
452: identity_permitted(Identity *id, SocketEntry *e, char *user,
453: const char **forward_hostnamep, const char **last_hostnamep)
454: {
455: size_t i;
456: const char **hp;
457: struct hostkey_sid *hks;
458: const struct sshkey *fromkey = NULL;
459: const char *test_user;
460: char *fp1, *fp2;
461:
462: /* XXX remove logspam */
463: debug3_f("entering: key %s comment \"%s\", %zu socket bindings, "
464: "%zu constraints", sshkey_type(id->key), id->comment,
465: e->nsession_ids, id->ndest_constraints);
466: if (id->ndest_constraints == 0)
467: return 0; /* unconstrained */
1.303 djm 468: if (e->session_bind_attempted && e->nsession_ids == 0) {
469: error_f("previous session bind failed on socket");
470: return -1;
471: }
1.281 djm 472: if (e->nsession_ids == 0)
473: return 0; /* local use */
474: /*
475: * Walk through the hops recorded by session_id and try to find a
476: * constraint that satisfies each.
477: */
478: for (i = 0; i < e->nsession_ids; i++) {
479: hks = e->session_ids + i;
480: if (hks->key == NULL)
481: fatal_f("internal error: no bound key");
482: /* XXX remove logspam */
483: fp1 = fp2 = NULL;
484: if (fromkey != NULL &&
485: (fp1 = sshkey_fingerprint(fromkey, SSH_FP_HASH_DEFAULT,
486: SSH_FP_DEFAULT)) == NULL)
487: fatal_f("fingerprint failed");
488: if ((fp2 = sshkey_fingerprint(hks->key, SSH_FP_HASH_DEFAULT,
489: SSH_FP_DEFAULT)) == NULL)
490: fatal_f("fingerprint failed");
491: debug3_f("socketentry fd=%d, entry %zu %s, "
492: "from hostkey %s %s to user %s hostkey %s %s",
493: e->fd, i, hks->forwarded ? "FORWARD" : "AUTH",
494: fromkey ? sshkey_type(fromkey) : "(ORIGIN)",
495: fromkey ? fp1 : "", user ? user : "(ANY)",
496: sshkey_type(hks->key), fp2);
497: free(fp1);
498: free(fp2);
499: /*
500: * Record the hostnames for the initial forwarding and
501: * the final destination.
502: */
503: hp = NULL;
504: if (i == e->nsession_ids - 1)
505: hp = last_hostnamep;
506: else if (i == 0)
507: hp = forward_hostnamep;
508: /* Special handling for final recorded binding */
509: test_user = NULL;
510: if (i == e->nsession_ids - 1) {
511: /* Can only check user at final hop */
512: test_user = user;
513: /*
514: * user is only presented for signature requests.
515: * If this is the case, make sure last binding is not
516: * for a forwarding.
517: */
518: if (hks->forwarded && user != NULL) {
519: error_f("tried to sign on forwarding hop");
520: return -1;
521: }
522: } else if (!hks->forwarded) {
523: error_f("tried to forward though signing bind");
524: return -1;
525: }
526: if (permitted_by_dest_constraints(fromkey, hks->key, id,
527: test_user, hp) != 0)
528: return -1;
529: fromkey = hks->key;
530: }
531: /*
532: * Another special case: if the last bound session ID was for a
533: * forwarding, and this function is not being called to check a sign
534: * request (i.e. no 'user' supplied), then only permit the key if
535: * there is a permission that would allow it to be used at another
536: * destination. This hides keys that are allowed to be used to
1.284 jsg 537: * authenticate *to* a host but not permitted for *use* beyond it.
1.281 djm 538: */
539: hks = &e->session_ids[e->nsession_ids - 1];
540: if (hks->forwarded && user == NULL &&
541: permitted_by_dest_constraints(hks->key, NULL, id,
542: NULL, NULL) != 0) {
543: debug3_f("key permitted at host but not after");
544: return -1;
545: }
546:
547: /* success */
548: return 0;
549: }
550:
1.303 djm 551: static int
552: socket_is_remote(SocketEntry *e)
553: {
554: return e->session_bind_attempted || (e->nsession_ids != 0);
555: }
556:
1.33 markus 557: /* return matching private key for given public key */
1.78 provos 558: static Identity *
1.221 djm 559: lookup_identity(struct sshkey *key)
1.33 markus 560: {
1.78 provos 561: Identity *id;
562:
1.221 djm 563: TAILQ_FOREACH(id, &idtab->idlist, next) {
1.194 markus 564: if (sshkey_equal(key, id->key))
1.78 provos 565: return (id);
1.33 markus 566: }
1.78 provos 567: return (NULL);
568: }
569:
1.107 markus 570: /* Check confirmation of keysign request */
571: static int
1.270 djm 572: confirm_key(Identity *id, const char *extra)
1.107 markus 573: {
1.122 djm 574: char *p;
1.107 markus 575: int ret = -1;
576:
1.194 markus 577: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 578: if (p != NULL &&
1.270 djm 579: ask_permission("Allow use of key %s?\nKey fingerprint %s.%s%s",
580: id->comment, p,
581: extra == NULL ? "" : "\n", extra == NULL ? "" : extra))
1.122 djm 582: ret = 0;
1.173 djm 583: free(p);
1.122 djm 584:
1.107 markus 585: return (ret);
586: }
587:
1.194 markus 588: static void
589: send_status(SocketEntry *e, int success)
590: {
591: int r;
592:
593: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
594: (r = sshbuf_put_u8(e->output, success ?
595: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
1.266 djm 596: fatal_fr(r, "compose");
1.194 markus 597: }
598:
1.33 markus 599: /* send list of supported public keys to 'client' */
1.55 itojun 600: static void
1.221 djm 601: process_request_identities(SocketEntry *e)
1.33 markus 602: {
1.96 deraadt 603: Identity *id;
1.281 djm 604: struct sshbuf *msg, *keys;
1.194 markus 605: int r;
1.301 djm 606: u_int i = 0, nentries = 0;
607: char *fp;
1.1 deraadt 608:
1.269 djm 609: debug2_f("entering");
610:
1.281 djm 611: if ((msg = sshbuf_new()) == NULL || (keys = sshbuf_new()) == NULL)
1.266 djm 612: fatal_f("sshbuf_new failed");
1.221 djm 613: TAILQ_FOREACH(id, &idtab->idlist, next) {
1.301 djm 614: if ((fp = sshkey_fingerprint(id->key, SSH_FP_HASH_DEFAULT,
615: SSH_FP_DEFAULT)) == NULL)
616: fatal_f("fingerprint failed");
617: debug_f("key %u / %u: %s %s", i++, idtab->nentries,
618: sshkey_ssh_name(id->key), fp);
619: dump_dest_constraints(__func__,
620: id->dest_constraints, id->ndest_constraints);
621: free(fp);
1.281 djm 622: /* identity not visible, don't include in response */
623: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
624: continue;
625: if ((r = sshkey_puts_opts(id->key, keys,
1.278 djm 626: SSHKEY_SERIALIZE_INFO)) != 0 ||
1.281 djm 627: (r = sshbuf_put_cstring(keys, id->comment)) != 0) {
1.266 djm 628: error_fr(r, "compose key/comment");
1.220 djm 629: continue;
1.33 markus 630: }
1.281 djm 631: nentries++;
1.21 markus 632: }
1.281 djm 633: debug2_f("replying with %u allowed of %u available keys",
634: nentries, idtab->nentries);
635: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
636: (r = sshbuf_put_u32(msg, nentries)) != 0 ||
637: (r = sshbuf_putb(msg, keys)) != 0)
638: fatal_fr(r, "compose");
1.194 markus 639: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 640: fatal_fr(r, "enqueue");
1.194 markus 641: sshbuf_free(msg);
1.281 djm 642: sshbuf_free(keys);
1.1 deraadt 643: }
644:
1.33 markus 645:
1.208 markus 646: static char *
647: agent_decode_alg(struct sshkey *key, u_int flags)
648: {
649: if (key->type == KEY_RSA) {
650: if (flags & SSH_AGENT_RSA_SHA2_256)
651: return "rsa-sha2-256";
652: else if (flags & SSH_AGENT_RSA_SHA2_512)
653: return "rsa-sha2-512";
1.235 djm 654: } else if (key->type == KEY_RSA_CERT) {
655: if (flags & SSH_AGENT_RSA_SHA2_256)
656: return "rsa-sha2-256-cert-v01@openssh.com";
657: else if (flags & SSH_AGENT_RSA_SHA2_512)
658: return "rsa-sha2-512-cert-v01@openssh.com";
1.208 markus 659: }
660: return NULL;
661: }
662:
1.258 djm 663: /*
1.270 djm 664: * Attempt to parse the contents of a buffer as a SSH publickey userauth
665: * request, checking its contents for consistency and matching the embedded
666: * key against the one that is being used for signing.
667: * Note: does not modify msg buffer.
1.282 djm 668: * Optionally extract the username, session ID and/or hostkey from the request.
1.258 djm 669: */
670: static int
1.270 djm 671: parse_userauth_request(struct sshbuf *msg, const struct sshkey *expected_key,
1.282 djm 672: char **userp, struct sshbuf **sess_idp, struct sshkey **hostkeyp)
1.258 djm 673: {
1.270 djm 674: struct sshbuf *b = NULL, *sess_id = NULL;
675: char *user = NULL, *service = NULL, *method = NULL, *pkalg = NULL;
1.258 djm 676: int r;
1.270 djm 677: u_char t, sig_follows;
1.282 djm 678: struct sshkey *mkey = NULL, *hostkey = NULL;
1.258 djm 679:
1.270 djm 680: if (userp != NULL)
681: *userp = NULL;
682: if (sess_idp != NULL)
683: *sess_idp = NULL;
1.282 djm 684: if (hostkeyp != NULL)
685: *hostkeyp = NULL;
1.270 djm 686: if ((b = sshbuf_fromb(msg)) == NULL)
687: fatal_f("sshbuf_fromb");
1.258 djm 688:
689: /* SSH userauth request */
1.270 djm 690: if ((r = sshbuf_froms(b, &sess_id)) != 0)
691: goto out;
692: if (sshbuf_len(sess_id) == 0) {
693: r = SSH_ERR_INVALID_FORMAT;
694: goto out;
695: }
696: if ((r = sshbuf_get_u8(b, &t)) != 0 || /* SSH2_MSG_USERAUTH_REQUEST */
697: (r = sshbuf_get_cstring(b, &user, NULL)) != 0 || /* server user */
698: (r = sshbuf_get_cstring(b, &service, NULL)) != 0 || /* service */
699: (r = sshbuf_get_cstring(b, &method, NULL)) != 0 || /* method */
700: (r = sshbuf_get_u8(b, &sig_follows)) != 0 || /* sig-follows */
701: (r = sshbuf_get_cstring(b, &pkalg, NULL)) != 0 || /* alg */
702: (r = sshkey_froms(b, &mkey)) != 0) /* key */
703: goto out;
704: if (t != SSH2_MSG_USERAUTH_REQUEST ||
705: sig_follows != 1 ||
706: strcmp(service, "ssh-connection") != 0 ||
707: !sshkey_equal(expected_key, mkey) ||
708: sshkey_type_from_name(pkalg) != expected_key->type) {
709: r = SSH_ERR_INVALID_FORMAT;
710: goto out;
711: }
1.282 djm 712: if (strcmp(method, "publickey-hostbound-v00@openssh.com") == 0) {
713: if ((r = sshkey_froms(b, &hostkey)) != 0)
714: goto out;
715: } else if (strcmp(method, "publickey") != 0) {
1.270 djm 716: r = SSH_ERR_INVALID_FORMAT;
717: goto out;
718: }
719: if (sshbuf_len(b) != 0) {
720: r = SSH_ERR_INVALID_FORMAT;
721: goto out;
722: }
723: /* success */
724: r = 0;
725: debug3_f("well formed userauth");
726: if (userp != NULL) {
727: *userp = user;
728: user = NULL;
729: }
730: if (sess_idp != NULL) {
731: *sess_idp = sess_id;
732: sess_id = NULL;
1.258 djm 733: }
1.282 djm 734: if (hostkeyp != NULL) {
735: *hostkeyp = hostkey;
736: hostkey = NULL;
737: }
1.270 djm 738: out:
739: sshbuf_free(b);
740: sshbuf_free(sess_id);
741: free(user);
742: free(service);
743: free(method);
744: free(pkalg);
1.258 djm 745: sshkey_free(mkey);
1.282 djm 746: sshkey_free(hostkey);
1.270 djm 747: return r;
748: }
749:
750: /*
751: * Attempt to parse the contents of a buffer as a SSHSIG signature request.
752: * Note: does not modify buffer.
753: */
754: static int
755: parse_sshsig_request(struct sshbuf *msg)
756: {
757: int r;
758: struct sshbuf *b;
759:
760: if ((b = sshbuf_fromb(msg)) == NULL)
761: fatal_f("sshbuf_fromb");
762:
763: if ((r = sshbuf_cmp(b, 0, "SSHSIG", 6)) != 0 ||
764: (r = sshbuf_consume(b, 6)) != 0 ||
765: (r = sshbuf_get_cstring(b, NULL, NULL)) != 0 || /* namespace */
766: (r = sshbuf_get_string_direct(b, NULL, NULL)) != 0 || /* reserved */
767: (r = sshbuf_get_cstring(b, NULL, NULL)) != 0 || /* hashalg */
768: (r = sshbuf_get_string_direct(b, NULL, NULL)) != 0) /* H(msg) */
769: goto out;
770: if (sshbuf_len(b) != 0) {
771: r = SSH_ERR_INVALID_FORMAT;
772: goto out;
773: }
774: /* success */
775: r = 0;
776: out:
1.258 djm 777: sshbuf_free(b);
1.270 djm 778: return r;
779: }
780:
781: /*
782: * This function inspects a message to be signed by a FIDO key that has a
783: * web-like application string (i.e. one that does not begin with "ssh:".
784: * It checks that the message is one of those expected for SSH operations
785: * (pubkey userauth, sshsig, CA key signing) to exclude signing challenges
786: * for the web.
787: */
788: static int
789: check_websafe_message_contents(struct sshkey *key, struct sshbuf *data)
790: {
1.282 djm 791: if (parse_userauth_request(data, key, NULL, NULL, NULL) == 0) {
1.270 djm 792: debug_f("signed data matches public key userauth request");
1.258 djm 793: return 1;
794: }
1.270 djm 795: if (parse_sshsig_request(data) == 0) {
796: debug_f("signed data matches SSHSIG signature request");
1.258 djm 797: return 1;
1.270 djm 798: }
1.258 djm 799:
1.270 djm 800: /* XXX check CA signature operation */
1.258 djm 801:
802: error("web-origin key attempting to sign non-SSH message");
803: return 0;
804: }
805:
1.280 djm 806: static int
807: buf_equal(const struct sshbuf *a, const struct sshbuf *b)
808: {
809: if (sshbuf_ptr(a) == NULL || sshbuf_ptr(b) == NULL)
810: return SSH_ERR_INVALID_ARGUMENT;
811: if (sshbuf_len(a) != sshbuf_len(b))
812: return SSH_ERR_INVALID_FORMAT;
813: if (timingsafe_bcmp(sshbuf_ptr(a), sshbuf_ptr(b), sshbuf_len(a)) != 0)
814: return SSH_ERR_INVALID_FORMAT;
815: return 0;
816: }
817:
1.33 markus 818: /* ssh2 only */
1.55 itojun 819: static void
1.33 markus 820: process_sign_request2(SocketEntry *e)
821: {
1.221 djm 822: u_char *signature = NULL;
1.281 djm 823: size_t slen = 0;
1.194 markus 824: u_int compat = 0, flags;
1.287 djm 825: int r, ok = -1, retried = 0;
826: char *fp = NULL, *pin = NULL, *prompt = NULL;
827: char *user = NULL, *sig_dest = NULL;
1.281 djm 828: const char *fwd_host = NULL, *dest_host = NULL;
1.280 djm 829: struct sshbuf *msg = NULL, *data = NULL, *sid = NULL;
1.283 djm 830: struct sshkey *key = NULL, *hostkey = NULL;
1.195 djm 831: struct identity *id;
1.251 djm 832: struct notifier_ctx *notifier = NULL;
1.194 markus 833:
1.270 djm 834: debug_f("entering");
835:
1.273 dtucker 836: if ((msg = sshbuf_new()) == NULL || (data = sshbuf_new()) == NULL)
1.266 djm 837: fatal_f("sshbuf_new failed");
1.221 djm 838: if ((r = sshkey_froms(e->request, &key)) != 0 ||
1.270 djm 839: (r = sshbuf_get_stringb(e->request, data)) != 0 ||
1.225 djm 840: (r = sshbuf_get_u32(e->request, &flags)) != 0) {
1.266 djm 841: error_fr(r, "parse");
1.225 djm 842: goto send;
843: }
844:
1.221 djm 845: if ((id = lookup_identity(key)) == NULL) {
1.266 djm 846: verbose_f("%s key not found", sshkey_type(key));
1.195 djm 847: goto send;
848: }
1.281 djm 849: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
850: SSH_FP_DEFAULT)) == NULL)
851: fatal_f("fingerprint failed");
852:
853: if (id->ndest_constraints != 0) {
854: if (e->nsession_ids == 0) {
855: logit_f("refusing use of destination-constrained key "
856: "to sign on unbound connection");
857: goto send;
858: }
1.283 djm 859: if (parse_userauth_request(data, key, &user, &sid,
860: &hostkey) != 0) {
1.281 djm 861: logit_f("refusing use of destination-constrained key "
862: "to sign an unidentified signature");
863: goto send;
864: }
865: /* XXX logspam */
866: debug_f("user=%s", user);
867: if (identity_permitted(id, e, user, &fwd_host, &dest_host) != 0)
868: goto send;
869: /* XXX display fwd_host/dest_host in askpass UI */
1.280 djm 870: /*
1.281 djm 871: * Ensure that the session ID is the most recent one
872: * registered on the socket - it should have been bound by
873: * ssh immediately before userauth.
1.280 djm 874: */
1.281 djm 875: if (buf_equal(sid,
876: e->session_ids[e->nsession_ids - 1].sid) != 0) {
877: error_f("unexpected session ID (%zu listed) on "
878: "signature request for target user %s with "
879: "key %s %s", e->nsession_ids, user,
880: sshkey_type(id->key), fp);
881: goto send;
1.280 djm 882: }
1.283 djm 883: /*
884: * Ensure that the hostkey embedded in the signature matches
885: * the one most recently bound to the socket. An exception is
886: * made for the initial forwarding hop.
887: */
888: if (e->nsession_ids > 1 && hostkey == NULL) {
889: error_f("refusing use of destination-constrained key: "
890: "no hostkey recorded in signature for forwarded "
891: "connection");
892: goto send;
893: }
894: if (hostkey != NULL && !sshkey_equal(hostkey,
895: e->session_ids[e->nsession_ids - 1].key)) {
896: error_f("refusing use of destination-constrained key: "
897: "mismatch between hostkey in request and most "
898: "recently bound session");
899: goto send;
900: }
1.281 djm 901: xasprintf(&sig_dest, "public key authentication request for "
902: "user \"%s\" to listed host", user);
1.280 djm 903: }
904: if (id->confirm && confirm_key(id, sig_dest) != 0) {
1.266 djm 905: verbose_f("user refused key");
1.195 djm 906: goto send;
907: }
1.258 djm 908: if (sshkey_is_sk(id->key)) {
1.292 djm 909: if (restrict_websafe &&
910: strncmp(id->key->sk_application, "ssh:", 4) != 0 &&
1.270 djm 911: !check_websafe_message_contents(key, data)) {
1.258 djm 912: /* error already logged */
913: goto send;
914: }
1.290 djm 915: if (id->key->sk_flags & SSH_SK_USER_PRESENCE_REQD) {
1.258 djm 916: notifier = notify_start(0,
1.280 djm 917: "Confirm user presence for key %s %s%s%s",
918: sshkey_type(id->key), fp,
919: sig_dest == NULL ? "" : "\n",
920: sig_dest == NULL ? "" : sig_dest);
1.258 djm 921: }
1.251 djm 922: }
1.287 djm 923: retry_pin:
1.251 djm 924: if ((r = sshkey_sign(id->key, &signature, &slen,
1.270 djm 925: sshbuf_ptr(data), sshbuf_len(data), agent_decode_alg(key, flags),
1.287 djm 926: id->sk_provider, pin, compat)) != 0) {
927: debug_fr(r, "sshkey_sign");
928: if (pin == NULL && !retried && sshkey_is_sk(id->key) &&
929: r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1.289 djm 930: notify_complete(notifier, NULL);
931: notifier = NULL;
1.287 djm 932: /* XXX include sig_dest */
933: xasprintf(&prompt, "Enter PIN%sfor %s key %s: ",
934: (id->key->sk_flags & SSH_SK_USER_PRESENCE_REQD) ?
935: " and confirm user presence " : " ",
936: sshkey_type(id->key), fp);
937: pin = read_passphrase(prompt, RP_USE_ASKPASS);
938: retried = 1;
939: goto retry_pin;
940: }
1.266 djm 941: error_fr(r, "sshkey_sign");
1.251 djm 942: goto send;
1.33 markus 943: }
1.195 djm 944: /* Success */
945: ok = 0;
1.299 djm 946: debug_f("good signature");
1.195 djm 947: send:
1.267 djm 948: notify_complete(notifier, "User presence confirmed");
1.270 djm 949:
1.33 markus 950: if (ok == 0) {
1.194 markus 951: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
952: (r = sshbuf_put_string(msg, signature, slen)) != 0)
1.266 djm 953: fatal_fr(r, "compose");
1.194 markus 954: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
1.266 djm 955: fatal_fr(r, "compose failure");
1.194 markus 956:
957: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 958: fatal_fr(r, "enqueue");
1.194 markus 959:
1.280 djm 960: sshbuf_free(sid);
1.270 djm 961: sshbuf_free(data);
1.194 markus 962: sshbuf_free(msg);
1.270 djm 963: sshkey_free(key);
1.283 djm 964: sshkey_free(hostkey);
1.270 djm 965: free(fp);
1.173 djm 966: free(signature);
1.280 djm 967: free(sig_dest);
968: free(user);
1.287 djm 969: free(prompt);
970: if (pin != NULL)
971: freezero(pin, strlen(pin));
1.1 deraadt 972: }
973:
1.33 markus 974: /* shared */
1.55 itojun 975: static void
1.221 djm 976: process_remove_identity(SocketEntry *e)
1.1 deraadt 977: {
1.194 markus 978: int r, success = 0;
979: struct sshkey *key = NULL;
1.221 djm 980: Identity *id;
1.21 markus 981:
1.269 djm 982: debug2_f("entering");
1.221 djm 983: if ((r = sshkey_froms(e->request, &key)) != 0) {
1.266 djm 984: error_fr(r, "parse key");
1.221 djm 985: goto done;
986: }
987: if ((id = lookup_identity(key)) == NULL) {
1.266 djm 988: debug_f("key not found");
1.221 djm 989: goto done;
990: }
1.281 djm 991: /* identity not visible, cannot be removed */
992: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
993: goto done; /* error already logged */
1.221 djm 994: /* We have this key, free it. */
995: if (idtab->nentries < 1)
1.266 djm 996: fatal_f("internal error: nentries %d", idtab->nentries);
1.221 djm 997: TAILQ_REMOVE(&idtab->idlist, id, next);
998: free_identity(id);
999: idtab->nentries--;
1000: success = 1;
1001: done:
1.276 djm 1002: sshkey_free(key);
1.194 markus 1003: send_status(e, success);
1.1 deraadt 1004: }
1005:
1.55 itojun 1006: static void
1.221 djm 1007: process_remove_all_identities(SocketEntry *e)
1.1 deraadt 1008: {
1.78 provos 1009: Identity *id;
1.21 markus 1010:
1.269 djm 1011: debug2_f("entering");
1.21 markus 1012: /* Loop over all identities and clear the keys. */
1.221 djm 1013: for (id = TAILQ_FIRST(&idtab->idlist); id;
1014: id = TAILQ_FIRST(&idtab->idlist)) {
1015: TAILQ_REMOVE(&idtab->idlist, id, next);
1.78 provos 1016: free_identity(id);
1.21 markus 1017: }
1018:
1019: /* Mark that there are no identities. */
1.221 djm 1020: idtab->nentries = 0;
1.21 markus 1021:
1022: /* Send success. */
1.194 markus 1023: send_status(e, 1);
1.1 deraadt 1024: }
1025:
1.155 dtucker 1026: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 1027: static time_t
1.89 markus 1028: reaper(void)
1029: {
1.175 dtucker 1030: time_t deadline = 0, now = monotime();
1.89 markus 1031: Identity *id, *nxt;
1032:
1.221 djm 1033: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
1034: nxt = TAILQ_NEXT(id, next);
1035: if (id->death == 0)
1036: continue;
1037: if (now >= id->death) {
1038: debug("expiring key '%s'", id->comment);
1039: TAILQ_REMOVE(&idtab->idlist, id, next);
1040: free_identity(id);
1041: idtab->nentries--;
1042: } else
1043: deadline = (deadline == 0) ? id->death :
1044: MINIMUM(deadline, id->death);
1.89 markus 1045: }
1.155 dtucker 1046: if (deadline == 0 || deadline <= now)
1047: return 0;
1048: else
1049: return (deadline - now);
1.89 markus 1050: }
1051:
1.271 djm 1052: static int
1.281 djm 1053: parse_dest_constraint_hop(struct sshbuf *b, struct dest_constraint_hop *dch)
1054: {
1055: u_char key_is_ca;
1056: size_t elen = 0;
1057: int r;
1058: struct sshkey *k = NULL;
1059: char *fp;
1060:
1061: memset(dch, '\0', sizeof(*dch));
1062: if ((r = sshbuf_get_cstring(b, &dch->user, NULL)) != 0 ||
1063: (r = sshbuf_get_cstring(b, &dch->hostname, NULL)) != 0 ||
1064: (r = sshbuf_get_string_direct(b, NULL, &elen)) != 0) {
1065: error_fr(r, "parse");
1066: goto out;
1067: }
1068: if (elen != 0) {
1069: error_f("unsupported extensions (len %zu)", elen);
1070: r = SSH_ERR_FEATURE_UNSUPPORTED;
1071: goto out;
1072: }
1073: if (*dch->hostname == '\0') {
1074: free(dch->hostname);
1075: dch->hostname = NULL;
1076: }
1077: if (*dch->user == '\0') {
1078: free(dch->user);
1079: dch->user = NULL;
1080: }
1081: while (sshbuf_len(b) != 0) {
1082: dch->keys = xrecallocarray(dch->keys, dch->nkeys,
1083: dch->nkeys + 1, sizeof(*dch->keys));
1084: dch->key_is_ca = xrecallocarray(dch->key_is_ca, dch->nkeys,
1085: dch->nkeys + 1, sizeof(*dch->key_is_ca));
1086: if ((r = sshkey_froms(b, &k)) != 0 ||
1087: (r = sshbuf_get_u8(b, &key_is_ca)) != 0)
1088: goto out;
1089: if ((fp = sshkey_fingerprint(k, SSH_FP_HASH_DEFAULT,
1090: SSH_FP_DEFAULT)) == NULL)
1091: fatal_f("fingerprint failed");
1092: debug3_f("%s%s%s: adding %skey %s %s",
1093: dch->user == NULL ? "" : dch->user,
1094: dch->user == NULL ? "" : "@",
1095: dch->hostname, key_is_ca ? "CA " : "", sshkey_type(k), fp);
1096: free(fp);
1097: dch->keys[dch->nkeys] = k;
1098: dch->key_is_ca[dch->nkeys] = key_is_ca != 0;
1099: dch->nkeys++;
1100: k = NULL; /* transferred */
1101: }
1102: /* success */
1103: r = 0;
1104: out:
1105: sshkey_free(k);
1106: return r;
1107: }
1108:
1109: static int
1110: parse_dest_constraint(struct sshbuf *m, struct dest_constraint *dc)
1111: {
1112: struct sshbuf *b = NULL, *frombuf = NULL, *tobuf = NULL;
1113: int r;
1114: size_t elen = 0;
1115:
1116: debug3_f("entering");
1117:
1118: memset(dc, '\0', sizeof(*dc));
1119: if ((r = sshbuf_froms(m, &b)) != 0 ||
1120: (r = sshbuf_froms(b, &frombuf)) != 0 ||
1121: (r = sshbuf_froms(b, &tobuf)) != 0 ||
1122: (r = sshbuf_get_string_direct(b, NULL, &elen)) != 0) {
1123: error_fr(r, "parse");
1124: goto out;
1125: }
1.297 jcs 1126: if ((r = parse_dest_constraint_hop(frombuf, &dc->from)) != 0 ||
1127: (r = parse_dest_constraint_hop(tobuf, &dc->to)) != 0)
1.281 djm 1128: goto out; /* already logged */
1129: if (elen != 0) {
1130: error_f("unsupported extensions (len %zu)", elen);
1131: r = SSH_ERR_FEATURE_UNSUPPORTED;
1132: goto out;
1133: }
1134: debug2_f("parsed %s (%u keys) > %s%s%s (%u keys)",
1135: dc->from.hostname ? dc->from.hostname : "(ORIGIN)", dc->from.nkeys,
1136: dc->to.user ? dc->to.user : "", dc->to.user ? "@" : "",
1137: dc->to.hostname ? dc->to.hostname : "(ANY)", dc->to.nkeys);
1138: /* check consistency */
1139: if ((dc->from.hostname == NULL) != (dc->from.nkeys == 0) ||
1140: dc->from.user != NULL) {
1141: error_f("inconsistent \"from\" specification");
1142: r = SSH_ERR_INVALID_FORMAT;
1143: goto out;
1144: }
1145: if (dc->to.hostname == NULL || dc->to.nkeys == 0) {
1146: error_f("incomplete \"to\" specification");
1147: r = SSH_ERR_INVALID_FORMAT;
1148: goto out;
1149: }
1150: /* success */
1151: r = 0;
1152: out:
1153: sshbuf_free(b);
1154: sshbuf_free(frombuf);
1155: sshbuf_free(tobuf);
1156: return r;
1157: }
1158:
1159: static int
1160: parse_key_constraint_extension(struct sshbuf *m, char **sk_providerp,
1.302 djm 1161: struct dest_constraint **dcsp, size_t *ndcsp, int *cert_onlyp,
1162: struct sshkey ***certs, size_t *ncerts)
1.277 djm 1163: {
1164: char *ext_name = NULL;
1165: int r;
1.281 djm 1166: struct sshbuf *b = NULL;
1.302 djm 1167: u_char v;
1168: struct sshkey *k;
1.277 djm 1169:
1170: if ((r = sshbuf_get_cstring(m, &ext_name, NULL)) != 0) {
1171: error_fr(r, "parse constraint extension");
1172: goto out;
1173: }
1174: debug_f("constraint ext %s", ext_name);
1175: if (strcmp(ext_name, "sk-provider@openssh.com") == 0) {
1176: if (sk_providerp == NULL) {
1177: error_f("%s not valid here", ext_name);
1178: r = SSH_ERR_INVALID_FORMAT;
1179: goto out;
1180: }
1181: if (*sk_providerp != NULL) {
1182: error_f("%s already set", ext_name);
1183: r = SSH_ERR_INVALID_FORMAT;
1184: goto out;
1185: }
1186: if ((r = sshbuf_get_cstring(m, sk_providerp, NULL)) != 0) {
1187: error_fr(r, "parse %s", ext_name);
1188: goto out;
1189: }
1.281 djm 1190: } else if (strcmp(ext_name,
1191: "restrict-destination-v00@openssh.com") == 0) {
1192: if (*dcsp != NULL) {
1193: error_f("%s already set", ext_name);
1194: goto out;
1195: }
1196: if ((r = sshbuf_froms(m, &b)) != 0) {
1197: error_fr(r, "parse %s outer", ext_name);
1198: goto out;
1199: }
1200: while (sshbuf_len(b) != 0) {
1201: if (*ndcsp >= AGENT_MAX_DEST_CONSTRAINTS) {
1202: error_f("too many %s constraints", ext_name);
1203: goto out;
1204: }
1205: *dcsp = xrecallocarray(*dcsp, *ndcsp, *ndcsp + 1,
1206: sizeof(**dcsp));
1207: if ((r = parse_dest_constraint(b,
1208: *dcsp + (*ndcsp)++)) != 0)
1209: goto out; /* error already logged */
1210: }
1.302 djm 1211: } else if (strcmp(ext_name,
1212: "associated-certs-v00@openssh.com") == 0) {
1213: if (certs == NULL || ncerts == NULL || cert_onlyp == NULL) {
1214: error_f("%s not valid here", ext_name);
1215: r = SSH_ERR_INVALID_FORMAT;
1216: goto out;
1217: }
1218: if (*certs != NULL) {
1219: error_f("%s already set", ext_name);
1220: goto out;
1221: }
1222: if ((r = sshbuf_get_u8(m, &v)) != 0 ||
1223: (r = sshbuf_froms(m, &b)) != 0) {
1224: error_fr(r, "parse %s", ext_name);
1225: goto out;
1226: }
1227: *cert_onlyp = v != 0;
1228: while (sshbuf_len(b) != 0) {
1229: if (*ncerts >= AGENT_MAX_EXT_CERTS) {
1230: error_f("too many %s constraints", ext_name);
1231: goto out;
1232: }
1233: *certs = xrecallocarray(*certs, *ncerts, *ncerts + 1,
1234: sizeof(**certs));
1235: if ((r = sshkey_froms(b, &k)) != 0) {
1236: error_fr(r, "parse key");
1237: goto out;
1238: }
1239: (*certs)[(*ncerts)++] = k;
1240: }
1.277 djm 1241: } else {
1242: error_f("unsupported constraint \"%s\"", ext_name);
1243: r = SSH_ERR_FEATURE_UNSUPPORTED;
1244: goto out;
1245: }
1246: /* success */
1247: r = 0;
1248: out:
1249: free(ext_name);
1.281 djm 1250: sshbuf_free(b);
1.277 djm 1251: return r;
1252: }
1253:
1254: static int
1.271 djm 1255: parse_key_constraints(struct sshbuf *m, struct sshkey *k, time_t *deathp,
1.281 djm 1256: u_int *secondsp, int *confirmp, char **sk_providerp,
1.302 djm 1257: struct dest_constraint **dcsp, size_t *ndcsp,
1258: int *cert_onlyp, size_t *ncerts, struct sshkey ***certs)
1.1 deraadt 1259: {
1.194 markus 1260: u_char ctype;
1.271 djm 1261: int r;
1262: u_int seconds, maxsign = 0;
1.33 markus 1263:
1.271 djm 1264: while (sshbuf_len(m)) {
1265: if ((r = sshbuf_get_u8(m, &ctype)) != 0) {
1.266 djm 1266: error_fr(r, "parse constraint type");
1.277 djm 1267: goto out;
1.194 markus 1268: }
1269: switch (ctype) {
1.94 markus 1270: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.271 djm 1271: if (*deathp != 0) {
1272: error_f("lifetime already set");
1.277 djm 1273: r = SSH_ERR_INVALID_FORMAT;
1274: goto out;
1.271 djm 1275: }
1276: if ((r = sshbuf_get_u32(m, &seconds)) != 0) {
1.266 djm 1277: error_fr(r, "parse lifetime constraint");
1.277 djm 1278: goto out;
1.194 markus 1279: }
1.271 djm 1280: *deathp = monotime() + seconds;
1281: *secondsp = seconds;
1.94 markus 1282: break;
1.107 markus 1283: case SSH_AGENT_CONSTRAIN_CONFIRM:
1.271 djm 1284: if (*confirmp != 0) {
1285: error_f("confirm already set");
1.277 djm 1286: r = SSH_ERR_INVALID_FORMAT;
1287: goto out;
1.271 djm 1288: }
1289: *confirmp = 1;
1.107 markus 1290: break;
1.228 markus 1291: case SSH_AGENT_CONSTRAIN_MAXSIGN:
1.271 djm 1292: if (k == NULL) {
1293: error_f("maxsign not valid here");
1.277 djm 1294: r = SSH_ERR_INVALID_FORMAT;
1295: goto out;
1.271 djm 1296: }
1297: if (maxsign != 0) {
1298: error_f("maxsign already set");
1.277 djm 1299: r = SSH_ERR_INVALID_FORMAT;
1300: goto out;
1.271 djm 1301: }
1302: if ((r = sshbuf_get_u32(m, &maxsign)) != 0) {
1.266 djm 1303: error_fr(r, "parse maxsign constraint");
1.277 djm 1304: goto out;
1.228 markus 1305: }
1306: if ((r = sshkey_enable_maxsign(k, maxsign)) != 0) {
1.266 djm 1307: error_fr(r, "enable maxsign");
1.277 djm 1308: goto out;
1.228 markus 1309: }
1310: break;
1.238 djm 1311: case SSH_AGENT_CONSTRAIN_EXTENSION:
1.277 djm 1312: if ((r = parse_key_constraint_extension(m,
1.302 djm 1313: sk_providerp, dcsp, ndcsp,
1314: cert_onlyp, certs, ncerts)) != 0)
1.277 djm 1315: goto out; /* error already logged */
1.238 djm 1316: break;
1.94 markus 1317: default:
1.266 djm 1318: error_f("Unknown constraint %d", ctype);
1.277 djm 1319: r = SSH_ERR_FEATURE_UNSUPPORTED;
1320: goto out;
1.94 markus 1321: }
1322: }
1.271 djm 1323: /* success */
1.277 djm 1324: r = 0;
1325: out:
1326: return r;
1.271 djm 1327: }
1328:
1329: static void
1330: process_add_identity(SocketEntry *e)
1331: {
1332: Identity *id;
1333: int success = 0, confirm = 0;
1.272 dtucker 1334: char *fp, *comment = NULL, *sk_provider = NULL;
1.271 djm 1335: char canonical_provider[PATH_MAX];
1336: time_t death = 0;
1337: u_int seconds = 0;
1.281 djm 1338: struct dest_constraint *dest_constraints = NULL;
1339: size_t ndest_constraints = 0;
1.271 djm 1340: struct sshkey *k = NULL;
1341: int r = SSH_ERR_INTERNAL_ERROR;
1342:
1343: debug2_f("entering");
1344: if ((r = sshkey_private_deserialize(e->request, &k)) != 0 ||
1345: k == NULL ||
1346: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
1347: error_fr(r, "parse");
1348: goto out;
1349: }
1350: if (parse_key_constraints(e->request, k, &death, &seconds, &confirm,
1.302 djm 1351: &sk_provider, &dest_constraints, &ndest_constraints,
1352: NULL, NULL, NULL) != 0) {
1.271 djm 1353: error_f("failed to parse constraints");
1354: sshbuf_reset(e->request);
1355: goto out;
1356: }
1.301 djm 1357: dump_dest_constraints(__func__, dest_constraints, ndest_constraints);
1.271 djm 1358:
1.238 djm 1359: if (sk_provider != NULL) {
1.240 markus 1360: if (!sshkey_is_sk(k)) {
1.255 naddy 1361: error("Cannot add provider: %s is not an "
1362: "authenticator-hosted key", sshkey_type(k));
1.271 djm 1363: goto out;
1.238 djm 1364: }
1.254 djm 1365: if (strcasecmp(sk_provider, "internal") == 0) {
1.266 djm 1366: debug_f("internal provider");
1.254 djm 1367: } else {
1.303 djm 1368: if (socket_is_remote(e) && !remote_add_provider) {
1.300 djm 1369: verbose("failed add of SK provider \"%.100s\": "
1370: "remote addition of providers is disabled",
1371: sk_provider);
1372: goto out;
1373: }
1.254 djm 1374: if (realpath(sk_provider, canonical_provider) == NULL) {
1375: verbose("failed provider \"%.100s\": "
1376: "realpath: %s", sk_provider,
1377: strerror(errno));
1.271 djm 1378: goto out;
1.254 djm 1379: }
1.238 djm 1380: free(sk_provider);
1.254 djm 1381: sk_provider = xstrdup(canonical_provider);
1382: if (match_pattern_list(sk_provider,
1.260 djm 1383: allowed_providers, 0) != 1) {
1.254 djm 1384: error("Refusing add key: "
1.260 djm 1385: "provider %s not allowed", sk_provider);
1.271 djm 1386: goto out;
1.254 djm 1387: }
1.238 djm 1388: }
1.242 markus 1389: }
1390: if ((r = sshkey_shield_private(k)) != 0) {
1.266 djm 1391: error_fr(r, "shield private");
1.271 djm 1392: goto out;
1.238 djm 1393: }
1.106 marc 1394: if (lifetime && !death)
1.175 dtucker 1395: death = monotime() + lifetime;
1.221 djm 1396: if ((id = lookup_identity(k)) == NULL) {
1.163 markus 1397: id = xcalloc(1, sizeof(Identity));
1.221 djm 1398: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
1.33 markus 1399: /* Increment the number of identities. */
1.221 djm 1400: idtab->nentries++;
1.33 markus 1401: } else {
1.281 djm 1402: /* identity not visible, do not update */
1403: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
1404: goto out; /* error already logged */
1.228 markus 1405: /* key state might have been updated */
1406: sshkey_free(id->key);
1.173 djm 1407: free(id->comment);
1.238 djm 1408: free(id->sk_provider);
1.281 djm 1409: free_dest_constraints(id->dest_constraints,
1410: id->ndest_constraints);
1.33 markus 1411: }
1.271 djm 1412: /* success */
1.228 markus 1413: id->key = k;
1.157 canacar 1414: id->comment = comment;
1415: id->death = death;
1416: id->confirm = confirm;
1.238 djm 1417: id->sk_provider = sk_provider;
1.281 djm 1418: id->dest_constraints = dest_constraints;
1419: id->ndest_constraints = ndest_constraints;
1.238 djm 1420:
1421: if ((fp = sshkey_fingerprint(k, SSH_FP_HASH_DEFAULT,
1422: SSH_FP_DEFAULT)) == NULL)
1.266 djm 1423: fatal_f("sshkey_fingerprint failed");
1424: debug_f("add %s %s \"%.100s\" (life: %u) (confirm: %u) "
1.281 djm 1425: "(provider: %s) (destination constraints: %zu)",
1426: sshkey_ssh_name(k), fp, comment, seconds, confirm,
1427: sk_provider == NULL ? "none" : sk_provider, ndest_constraints);
1.238 djm 1428: free(fp);
1.271 djm 1429: /* transferred */
1430: k = NULL;
1431: comment = NULL;
1432: sk_provider = NULL;
1.281 djm 1433: dest_constraints = NULL;
1434: ndest_constraints = 0;
1.271 djm 1435: success = 1;
1436: out:
1437: free(sk_provider);
1438: free(comment);
1439: sshkey_free(k);
1.281 djm 1440: free_dest_constraints(dest_constraints, ndest_constraints);
1.194 markus 1441: send_status(e, success);
1.1 deraadt 1442: }
1443:
1.88 markus 1444: /* XXX todo: encrypt sensitive data with passphrase */
1445: static void
1446: process_lock_agent(SocketEntry *e, int lock)
1447: {
1.203 dtucker 1448: int r, success = 0, delay;
1.213 djm 1449: char *passwd;
1450: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 1451: static u_int fail_count = 0;
1452: size_t pwlen;
1453:
1.269 djm 1454: debug2_f("entering");
1.226 djm 1455: /*
1456: * This is deliberately fatal: the user has requested that we lock,
1457: * but we can't parse their request properly. The only safe thing to
1458: * do is abort.
1459: */
1.203 dtucker 1460: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
1.266 djm 1461: fatal_fr(r, "parse");
1.203 dtucker 1462: if (pwlen == 0) {
1463: debug("empty password not supported");
1464: } else if (locked && !lock) {
1465: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1466: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
1467: fatal("bcrypt_pbkdf");
1.213 djm 1468: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 1469: debug("agent unlocked");
1470: locked = 0;
1471: fail_count = 0;
1.213 djm 1472: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 1473: success = 1;
1474: } else {
1475: /* delay in 0.1s increments up to 10s */
1476: if (fail_count < 100)
1477: fail_count++;
1478: delay = 100000 * fail_count;
1479: debug("unlock failed, delaying %0.1lf seconds",
1480: (double)delay/1000000);
1481: usleep(delay);
1482: }
1483: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 1484: } else if (!locked && lock) {
1.203 dtucker 1485: debug("agent locked");
1.88 markus 1486: locked = 1;
1.203 dtucker 1487: arc4random_buf(lock_salt, sizeof(lock_salt));
1488: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 djm 1489: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 1490: fatal("bcrypt_pbkdf");
1.88 markus 1491: success = 1;
1492: }
1.256 jsg 1493: freezero(passwd, pwlen);
1.194 markus 1494: send_status(e, success);
1.88 markus 1495: }
1496:
1497: static void
1.221 djm 1498: no_identities(SocketEntry *e)
1.88 markus 1499: {
1.194 markus 1500: struct sshbuf *msg;
1501: int r;
1.88 markus 1502:
1.194 markus 1503: if ((msg = sshbuf_new()) == NULL)
1.266 djm 1504: fatal_f("sshbuf_new failed");
1.221 djm 1505: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
1.194 markus 1506: (r = sshbuf_put_u32(msg, 0)) != 0 ||
1507: (r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 1508: fatal_fr(r, "compose");
1.194 markus 1509: sshbuf_free(msg);
1.88 markus 1510: }
1.59 markus 1511:
1.302 djm 1512: /* Add an identity to idlist; takes ownership of 'key' and 'comment' */
1513: static void
1514: add_p11_identity(struct sshkey *key, char *comment, const char *provider,
1.304 ! djm 1515: time_t death, u_int confirm, struct dest_constraint *dest_constraints,
1.302 djm 1516: size_t ndest_constraints)
1517: {
1518: Identity *id;
1519:
1520: if (lookup_identity(key) != NULL) {
1521: sshkey_free(key);
1522: free(comment);
1523: return;
1524: }
1525: id = xcalloc(1, sizeof(Identity));
1526: id->key = key;
1527: id->comment = comment;
1528: id->provider = xstrdup(provider);
1529: id->death = death;
1530: id->confirm = confirm;
1531: id->dest_constraints = dup_dest_constraints(dest_constraints,
1532: ndest_constraints);
1533: id->ndest_constraints = ndest_constraints;
1534: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
1535: idtab->nentries++;
1536: }
1537:
1.163 markus 1538: #ifdef ENABLE_PKCS11
1.59 markus 1539: static void
1.158 djm 1540: process_add_smartcard_key(SocketEntry *e)
1.59 markus 1541: {
1.226 djm 1542: char *provider = NULL, *pin = NULL, canonical_provider[PATH_MAX];
1.253 djm 1543: char **comments = NULL;
1.221 djm 1544: int r, i, count = 0, success = 0, confirm = 0;
1.271 djm 1545: u_int seconds = 0;
1.174 dtucker 1546: time_t death = 0;
1.194 markus 1547: struct sshkey **keys = NULL, *k;
1.281 djm 1548: struct dest_constraint *dest_constraints = NULL;
1.302 djm 1549: size_t j, ndest_constraints = 0, ncerts = 0;
1550: struct sshkey **certs = NULL;
1551: int cert_only = 0;
1.75 deraadt 1552:
1.269 djm 1553: debug2_f("entering");
1.194 markus 1554: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
1.226 djm 1555: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) {
1.266 djm 1556: error_fr(r, "parse");
1.226 djm 1557: goto send;
1558: }
1.271 djm 1559: if (parse_key_constraints(e->request, NULL, &death, &seconds, &confirm,
1.302 djm 1560: NULL, &dest_constraints, &ndest_constraints, &cert_only,
1561: &ncerts, &certs) != 0) {
1.271 djm 1562: error_f("failed to parse constraints");
1563: goto send;
1.110 djm 1564: }
1.301 djm 1565: dump_dest_constraints(__func__, dest_constraints, ndest_constraints);
1.303 djm 1566: if (socket_is_remote(e) && !remote_add_provider) {
1.300 djm 1567: verbose("failed PKCS#11 add of \"%.100s\": remote addition of "
1568: "providers is disabled", provider);
1569: goto send;
1570: }
1.215 djm 1571: if (realpath(provider, canonical_provider) == NULL) {
1572: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
1573: provider, strerror(errno));
1574: goto send;
1575: }
1.260 djm 1576: if (match_pattern_list(canonical_provider, allowed_providers, 0) != 1) {
1.215 djm 1577: verbose("refusing PKCS#11 add of \"%.100s\": "
1.260 djm 1578: "provider not allowed", canonical_provider);
1.215 djm 1579: goto send;
1580: }
1.266 djm 1581: debug_f("add %.100s", canonical_provider);
1.110 djm 1582: if (lifetime && !death)
1.175 dtucker 1583: death = monotime() + lifetime;
1.110 djm 1584:
1.253 djm 1585: count = pkcs11_add_provider(canonical_provider, pin, &keys, &comments);
1.163 markus 1586: for (i = 0; i < count; i++) {
1.302 djm 1587: if (comments[i] == NULL || comments[i][0] == '\0') {
1588: free(comments[i]);
1589: comments[i] = xstrdup(canonical_provider);
1590: }
1591: for (j = 0; j < ncerts; j++) {
1592: if (!sshkey_is_cert(certs[j]))
1593: continue;
1594: if (!sshkey_equal_public(keys[i], certs[j]))
1595: continue;
1596: if (pkcs11_make_cert(keys[i], certs[j], &k) != 0)
1597: continue;
1598: add_p11_identity(k, xstrdup(comments[i]),
1599: canonical_provider, death, confirm,
1600: dest_constraints, ndest_constraints);
1601: success = 1;
1602: }
1603: if (!cert_only && lookup_identity(keys[i]) == NULL) {
1604: add_p11_identity(keys[i], comments[i],
1605: canonical_provider, death, confirm,
1.301 djm 1606: dest_constraints, ndest_constraints);
1.302 djm 1607: keys[i] = NULL; /* transferred */
1608: comments[i] = NULL; /* transferred */
1.84 markus 1609: success = 1;
1610: }
1.271 djm 1611: /* XXX update constraints for existing keys */
1.253 djm 1612: sshkey_free(keys[i]);
1613: free(comments[i]);
1.59 markus 1614: }
1615: send:
1.173 djm 1616: free(pin);
1617: free(provider);
1618: free(keys);
1.253 djm 1619: free(comments);
1.281 djm 1620: free_dest_constraints(dest_constraints, ndest_constraints);
1.302 djm 1621: for (j = 0; j < ncerts; j++)
1622: sshkey_free(certs[j]);
1623: free(certs);
1.194 markus 1624: send_status(e, success);
1.59 markus 1625: }
1626:
1627: static void
1628: process_remove_smartcard_key(SocketEntry *e)
1629: {
1.217 djm 1630: char *provider = NULL, *pin = NULL, canonical_provider[PATH_MAX];
1.221 djm 1631: int r, success = 0;
1.163 markus 1632: Identity *id, *nxt;
1.59 markus 1633:
1.269 djm 1634: debug2_f("entering");
1.194 markus 1635: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
1.226 djm 1636: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) {
1.266 djm 1637: error_fr(r, "parse");
1.226 djm 1638: goto send;
1639: }
1.173 djm 1640: free(pin);
1.59 markus 1641:
1.217 djm 1642: if (realpath(provider, canonical_provider) == NULL) {
1643: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
1644: provider, strerror(errno));
1645: goto send;
1646: }
1647:
1.266 djm 1648: debug_f("remove %.100s", canonical_provider);
1.221 djm 1649: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
1650: nxt = TAILQ_NEXT(id, next);
1651: /* Skip file--based keys */
1652: if (id->provider == NULL)
1653: continue;
1654: if (!strcmp(canonical_provider, id->provider)) {
1655: TAILQ_REMOVE(&idtab->idlist, id, next);
1656: free_identity(id);
1657: idtab->nentries--;
1.59 markus 1658: }
1659: }
1.217 djm 1660: if (pkcs11_del_provider(canonical_provider) == 0)
1.163 markus 1661: success = 1;
1662: else
1.266 djm 1663: error_f("pkcs11_del_provider failed");
1.218 deraadt 1664: send:
1.173 djm 1665: free(provider);
1.194 markus 1666: send_status(e, success);
1.59 markus 1667: }
1.163 markus 1668: #endif /* ENABLE_PKCS11 */
1.59 markus 1669:
1.280 djm 1670: static int
1671: process_ext_session_bind(SocketEntry *e)
1672: {
1673: int r, sid_match, key_match;
1674: struct sshkey *key = NULL;
1675: struct sshbuf *sid = NULL, *sig = NULL;
1676: char *fp = NULL;
1677: size_t i;
1.281 djm 1678: u_char fwd = 0;
1.280 djm 1679:
1680: debug2_f("entering");
1.303 djm 1681: e->session_bind_attempted = 1;
1.280 djm 1682: if ((r = sshkey_froms(e->request, &key)) != 0 ||
1683: (r = sshbuf_froms(e->request, &sid)) != 0 ||
1684: (r = sshbuf_froms(e->request, &sig)) != 0 ||
1685: (r = sshbuf_get_u8(e->request, &fwd)) != 0) {
1686: error_fr(r, "parse");
1687: goto out;
1688: }
1689: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
1690: SSH_FP_DEFAULT)) == NULL)
1691: fatal_f("fingerprint failed");
1692: /* check signature with hostkey on session ID */
1693: if ((r = sshkey_verify(key, sshbuf_ptr(sig), sshbuf_len(sig),
1694: sshbuf_ptr(sid), sshbuf_len(sid), NULL, 0, NULL)) != 0) {
1695: error_fr(r, "sshkey_verify for %s %s", sshkey_type(key), fp);
1696: goto out;
1697: }
1698: /* check whether sid/key already recorded */
1699: for (i = 0; i < e->nsession_ids; i++) {
1.281 djm 1700: if (!e->session_ids[i].forwarded) {
1701: error_f("attempt to bind session ID to socket "
1702: "previously bound for authentication attempt");
1703: r = -1;
1704: goto out;
1705: }
1.280 djm 1706: sid_match = buf_equal(sid, e->session_ids[i].sid) == 0;
1707: key_match = sshkey_equal(key, e->session_ids[i].key);
1708: if (sid_match && key_match) {
1709: debug_f("session ID already recorded for %s %s",
1710: sshkey_type(key), fp);
1711: r = 0;
1712: goto out;
1713: } else if (sid_match) {
1714: error_f("session ID recorded against different key "
1715: "for %s %s", sshkey_type(key), fp);
1716: r = -1;
1717: goto out;
1718: }
1719: /*
1720: * new sid with previously-seen key can happen, e.g. multiple
1721: * connections to the same host.
1722: */
1723: }
1724: /* record new key/sid */
1725: if (e->nsession_ids >= AGENT_MAX_SESSION_IDS) {
1726: error_f("too many session IDs recorded");
1727: goto out;
1728: }
1729: e->session_ids = xrecallocarray(e->session_ids, e->nsession_ids,
1730: e->nsession_ids + 1, sizeof(*e->session_ids));
1731: i = e->nsession_ids++;
1732: debug_f("recorded %s %s (slot %zu of %d)", sshkey_type(key), fp, i,
1733: AGENT_MAX_SESSION_IDS);
1734: e->session_ids[i].key = key;
1735: e->session_ids[i].forwarded = fwd != 0;
1736: key = NULL; /* transferred */
1737: /* can't transfer sid; it's refcounted and scoped to request's life */
1738: if ((e->session_ids[i].sid = sshbuf_new()) == NULL)
1739: fatal_f("sshbuf_new");
1740: if ((r = sshbuf_putb(e->session_ids[i].sid, sid)) != 0)
1741: fatal_fr(r, "sshbuf_putb session ID");
1742: /* success */
1743: r = 0;
1744: out:
1.288 djm 1745: free(fp);
1.280 djm 1746: sshkey_free(key);
1747: sshbuf_free(sid);
1748: sshbuf_free(sig);
1749: return r == 0 ? 1 : 0;
1750: }
1751:
1752: static void
1753: process_extension(SocketEntry *e)
1754: {
1755: int r, success = 0;
1756: char *name;
1757:
1758: debug2_f("entering");
1759: if ((r = sshbuf_get_cstring(e->request, &name, NULL)) != 0) {
1760: error_fr(r, "parse");
1761: goto send;
1762: }
1763: if (strcmp(name, "session-bind@openssh.com") == 0)
1764: success = process_ext_session_bind(e);
1765: else
1766: debug_f("unsupported extension \"%s\"", name);
1.285 djm 1767: free(name);
1.280 djm 1768: send:
1769: send_status(e, success);
1770: }
1.264 djm 1771: /*
1772: * dispatch incoming message.
1773: * returns 1 on success, 0 for incomplete messages or -1 on error.
1774: */
1.223 djm 1775: static int
1776: process_message(u_int socknum)
1.1 deraadt 1777: {
1.194 markus 1778: u_int msg_len;
1779: u_char type;
1780: const u_char *cp;
1781: int r;
1.223 djm 1782: SocketEntry *e;
1783:
1.266 djm 1784: if (socknum >= sockets_alloc)
1785: fatal_f("sock %u >= allocated %u", socknum, sockets_alloc);
1.223 djm 1786: e = &sockets[socknum];
1.89 markus 1787:
1.194 markus 1788: if (sshbuf_len(e->input) < 5)
1.223 djm 1789: return 0; /* Incomplete message header. */
1.194 markus 1790: cp = sshbuf_ptr(e->input);
1791: msg_len = PEEK_U32(cp);
1.223 djm 1792: if (msg_len > AGENT_MAX_LEN) {
1.266 djm 1793: debug_f("socket %u (fd=%d) message too long %u > %u",
1794: socknum, e->fd, msg_len, AGENT_MAX_LEN);
1.223 djm 1795: return -1;
1.21 markus 1796: }
1.194 markus 1797: if (sshbuf_len(e->input) < msg_len + 4)
1.223 djm 1798: return 0; /* Incomplete message body. */
1.87 markus 1799:
1800: /* move the current input to e->request */
1.194 markus 1801: sshbuf_reset(e->request);
1802: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
1.223 djm 1803: (r = sshbuf_get_u8(e->request, &type)) != 0) {
1804: if (r == SSH_ERR_MESSAGE_INCOMPLETE ||
1805: r == SSH_ERR_STRING_TOO_LARGE) {
1.266 djm 1806: error_fr(r, "parse");
1.223 djm 1807: return -1;
1808: }
1.266 djm 1809: fatal_fr(r, "parse");
1.223 djm 1810: }
1811:
1.266 djm 1812: debug_f("socket %u (fd=%d) type %d", socknum, e->fd, type);
1.21 markus 1813:
1.230 djm 1814: /* check whether agent is locked */
1.88 markus 1815: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 1816: sshbuf_reset(e->request);
1.88 markus 1817: switch (type) {
1818: case SSH2_AGENTC_REQUEST_IDENTITIES:
1819: /* send empty lists */
1.221 djm 1820: no_identities(e);
1.88 markus 1821: break;
1822: default:
1823: /* send a fail message for all other request types */
1.194 markus 1824: send_status(e, 0);
1.88 markus 1825: }
1.264 djm 1826: return 1;
1.88 markus 1827: }
1828:
1.21 markus 1829: switch (type) {
1.88 markus 1830: case SSH_AGENTC_LOCK:
1831: case SSH_AGENTC_UNLOCK:
1832: process_lock_agent(e, type == SSH_AGENTC_LOCK);
1833: break;
1.21 markus 1834: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.221 djm 1835: process_remove_all_identities(e); /* safe for !WITH_SSH1 */
1.33 markus 1836: break;
1837: /* ssh2 */
1838: case SSH2_AGENTC_SIGN_REQUEST:
1839: process_sign_request2(e);
1840: break;
1841: case SSH2_AGENTC_REQUEST_IDENTITIES:
1.221 djm 1842: process_request_identities(e);
1.33 markus 1843: break;
1844: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 1845: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.221 djm 1846: process_add_identity(e);
1.33 markus 1847: break;
1848: case SSH2_AGENTC_REMOVE_IDENTITY:
1.221 djm 1849: process_remove_identity(e);
1.33 markus 1850: break;
1851: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
1.221 djm 1852: process_remove_all_identities(e);
1.21 markus 1853: break;
1.163 markus 1854: #ifdef ENABLE_PKCS11
1.59 markus 1855: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 1856: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 1857: process_add_smartcard_key(e);
1.75 deraadt 1858: break;
1.59 markus 1859: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
1860: process_remove_smartcard_key(e);
1.75 deraadt 1861: break;
1.163 markus 1862: #endif /* ENABLE_PKCS11 */
1.280 djm 1863: case SSH_AGENTC_EXTENSION:
1864: process_extension(e);
1865: break;
1.21 markus 1866: default:
1867: /* Unknown message. Respond with failure. */
1868: error("Unknown message %d", type);
1.194 markus 1869: sshbuf_reset(e->request);
1870: send_status(e, 0);
1.21 markus 1871: break;
1872: }
1.264 djm 1873: return 1;
1.1 deraadt 1874: }
1875:
1.55 itojun 1876: static void
1.73 stevesk 1877: new_socket(sock_type type, int fd)
1.1 deraadt 1878: {
1.112 markus 1879: u_int i, old_alloc, new_alloc;
1.96 deraadt 1880:
1.269 djm 1881: debug_f("type = %s", type == AUTH_CONNECTION ? "CONNECTION" :
1882: (type == AUTH_SOCKET ? "SOCKET" : "UNKNOWN"));
1.119 djm 1883: set_nonblock(fd);
1.21 markus 1884:
1885: if (fd > max_fd)
1886: max_fd = fd;
1887:
1888: for (i = 0; i < sockets_alloc; i++)
1889: if (sockets[i].type == AUTH_UNUSED) {
1890: sockets[i].fd = fd;
1.266 djm 1891: if ((sockets[i].input = sshbuf_new()) == NULL ||
1892: (sockets[i].output = sshbuf_new()) == NULL ||
1893: (sockets[i].request = sshbuf_new()) == NULL)
1894: fatal_f("sshbuf_new failed");
1.112 markus 1895: sockets[i].type = type;
1.21 markus 1896: return;
1897: }
1898: old_alloc = sockets_alloc;
1.112 markus 1899: new_alloc = sockets_alloc + 10;
1.269 djm 1900: sockets = xrecallocarray(sockets, old_alloc, new_alloc,
1901: sizeof(sockets[0]));
1.112 markus 1902: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 1903: sockets[i].type = AUTH_UNUSED;
1.112 markus 1904: sockets_alloc = new_alloc;
1.21 markus 1905: sockets[old_alloc].fd = fd;
1.266 djm 1906: if ((sockets[old_alloc].input = sshbuf_new()) == NULL ||
1907: (sockets[old_alloc].output = sshbuf_new()) == NULL ||
1908: (sockets[old_alloc].request = sshbuf_new()) == NULL)
1909: fatal_f("sshbuf_new failed");
1.112 markus 1910: sockets[old_alloc].type = type;
1.1 deraadt 1911: }
1912:
1.55 itojun 1913: static int
1.223 djm 1914: handle_socket_read(u_int socknum)
1.1 deraadt 1915: {
1.223 djm 1916: struct sockaddr_un sunaddr;
1917: socklen_t slen;
1918: uid_t euid;
1919: gid_t egid;
1920: int fd;
1921:
1922: slen = sizeof(sunaddr);
1923: fd = accept(sockets[socknum].fd, (struct sockaddr *)&sunaddr, &slen);
1.237 deraadt 1924: if (fd == -1) {
1.223 djm 1925: error("accept from AUTH_SOCKET: %s", strerror(errno));
1926: return -1;
1927: }
1.237 deraadt 1928: if (getpeereid(fd, &euid, &egid) == -1) {
1.223 djm 1929: error("getpeereid %d failed: %s", fd, strerror(errno));
1930: close(fd);
1931: return -1;
1932: }
1933: if ((euid != 0) && (getuid() != euid)) {
1934: error("uid mismatch: peer euid %u != uid %u",
1935: (u_int) euid, (u_int) getuid());
1936: close(fd);
1937: return -1;
1938: }
1939: new_socket(AUTH_CONNECTION, fd);
1940: return 0;
1941: }
1942:
1943: static int
1944: handle_conn_read(u_int socknum)
1945: {
1.233 djm 1946: char buf[AGENT_RBUF_LEN];
1.223 djm 1947: ssize_t len;
1948: int r;
1949:
1950: if ((len = read(sockets[socknum].fd, buf, sizeof(buf))) <= 0) {
1951: if (len == -1) {
1952: if (errno == EAGAIN || errno == EINTR)
1953: return 0;
1.266 djm 1954: error_f("read error on socket %u (fd %d): %s",
1955: socknum, sockets[socknum].fd, strerror(errno));
1.223 djm 1956: }
1957: return -1;
1958: }
1959: if ((r = sshbuf_put(sockets[socknum].input, buf, len)) != 0)
1.266 djm 1960: fatal_fr(r, "compose");
1.223 djm 1961: explicit_bzero(buf, sizeof(buf));
1.264 djm 1962: for (;;) {
1963: if ((r = process_message(socknum)) == -1)
1964: return -1;
1965: else if (r == 0)
1966: break;
1967: }
1.223 djm 1968: return 0;
1969: }
1970:
1971: static int
1972: handle_conn_write(u_int socknum)
1973: {
1974: ssize_t len;
1975: int r;
1976:
1977: if (sshbuf_len(sockets[socknum].output) == 0)
1978: return 0; /* shouldn't happen */
1979: if ((len = write(sockets[socknum].fd,
1980: sshbuf_ptr(sockets[socknum].output),
1981: sshbuf_len(sockets[socknum].output))) <= 0) {
1982: if (len == -1) {
1983: if (errno == EAGAIN || errno == EINTR)
1984: return 0;
1.266 djm 1985: error_f("read error on socket %u (fd %d): %s",
1986: socknum, sockets[socknum].fd, strerror(errno));
1.223 djm 1987: }
1988: return -1;
1989: }
1990: if ((r = sshbuf_consume(sockets[socknum].output, len)) != 0)
1.266 djm 1991: fatal_fr(r, "consume");
1.223 djm 1992: return 0;
1993: }
1994:
1995: static void
1.231 djm 1996: after_poll(struct pollfd *pfd, size_t npfd, u_int maxfds)
1.223 djm 1997: {
1998: size_t i;
1.231 djm 1999: u_int socknum, activefds = npfd;
1.223 djm 2000:
2001: for (i = 0; i < npfd; i++) {
2002: if (pfd[i].revents == 0)
2003: continue;
2004: /* Find sockets entry */
2005: for (socknum = 0; socknum < sockets_alloc; socknum++) {
2006: if (sockets[socknum].type != AUTH_SOCKET &&
2007: sockets[socknum].type != AUTH_CONNECTION)
2008: continue;
2009: if (pfd[i].fd == sockets[socknum].fd)
2010: break;
2011: }
2012: if (socknum >= sockets_alloc) {
1.266 djm 2013: error_f("no socket for fd %d", pfd[i].fd);
1.223 djm 2014: continue;
2015: }
2016: /* Process events */
2017: switch (sockets[socknum].type) {
2018: case AUTH_SOCKET:
1.231 djm 2019: if ((pfd[i].revents & (POLLIN|POLLERR)) == 0)
2020: break;
2021: if (npfd > maxfds) {
2022: debug3("out of fds (active %u >= limit %u); "
2023: "skipping accept", activefds, maxfds);
2024: break;
2025: }
2026: if (handle_socket_read(socknum) == 0)
2027: activefds++;
1.223 djm 2028: break;
2029: case AUTH_CONNECTION:
1.279 djm 2030: if ((pfd[i].revents & (POLLIN|POLLHUP|POLLERR)) != 0 &&
2031: handle_conn_read(socknum) != 0)
1.231 djm 2032: goto close_sock;
2033: if ((pfd[i].revents & (POLLOUT|POLLHUP)) != 0 &&
2034: handle_conn_write(socknum) != 0) {
2035: close_sock:
2036: if (activefds == 0)
2037: fatal("activefds == 0 at close_sock");
1.223 djm 2038: close_socket(&sockets[socknum]);
1.231 djm 2039: activefds--;
1.223 djm 2040: break;
2041: }
2042: break;
2043: default:
2044: break;
2045: }
2046: }
2047: }
2048:
2049: static int
1.231 djm 2050: prepare_poll(struct pollfd **pfdp, size_t *npfdp, int *timeoutp, u_int maxfds)
1.223 djm 2051: {
2052: struct pollfd *pfd = *pfdp;
2053: size_t i, j, npfd = 0;
1.174 dtucker 2054: time_t deadline;
1.233 djm 2055: int r;
1.46 markus 2056:
1.223 djm 2057: /* Count active sockets */
1.46 markus 2058: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 2059: switch (sockets[i].type) {
2060: case AUTH_SOCKET:
2061: case AUTH_CONNECTION:
1.223 djm 2062: npfd++;
1.21 markus 2063: break;
2064: case AUTH_UNUSED:
2065: break;
2066: default:
2067: fatal("Unknown socket type %d", sockets[i].type);
2068: break;
2069: }
1.46 markus 2070: }
1.223 djm 2071: if (npfd != *npfdp &&
2072: (pfd = recallocarray(pfd, *npfdp, npfd, sizeof(*pfd))) == NULL)
1.266 djm 2073: fatal_f("recallocarray failed");
1.223 djm 2074: *pfdp = pfd;
2075: *npfdp = npfd;
1.46 markus 2076:
1.223 djm 2077: for (i = j = 0; i < sockets_alloc; i++) {
1.46 markus 2078: switch (sockets[i].type) {
2079: case AUTH_SOCKET:
1.231 djm 2080: if (npfd > maxfds) {
2081: debug3("out of fds (active %zu >= limit %u); "
2082: "skipping arming listener", npfd, maxfds);
2083: break;
2084: }
2085: pfd[j].fd = sockets[i].fd;
2086: pfd[j].revents = 0;
2087: pfd[j].events = POLLIN;
2088: j++;
2089: break;
1.46 markus 2090: case AUTH_CONNECTION:
1.223 djm 2091: pfd[j].fd = sockets[i].fd;
2092: pfd[j].revents = 0;
1.233 djm 2093: /*
2094: * Only prepare to read if we can handle a full-size
2095: * input read buffer and enqueue a max size reply..
2096: */
2097: if ((r = sshbuf_check_reserve(sockets[i].input,
2098: AGENT_RBUF_LEN)) == 0 &&
2099: (r = sshbuf_check_reserve(sockets[i].output,
1.278 djm 2100: AGENT_MAX_LEN)) == 0)
1.233 djm 2101: pfd[j].events = POLLIN;
1.266 djm 2102: else if (r != SSH_ERR_NO_BUFFER_SPACE)
2103: fatal_fr(r, "reserve");
1.194 markus 2104: if (sshbuf_len(sockets[i].output) > 0)
1.223 djm 2105: pfd[j].events |= POLLOUT;
2106: j++;
1.46 markus 2107: break;
2108: default:
2109: break;
2110: }
2111: }
1.155 dtucker 2112: deadline = reaper();
2113: if (parent_alive_interval != 0)
2114: deadline = (deadline == 0) ? parent_alive_interval :
1.214 deraadt 2115: MINIMUM(deadline, parent_alive_interval);
1.155 dtucker 2116: if (deadline == 0) {
1.224 djm 2117: *timeoutp = -1; /* INFTIM */
1.155 dtucker 2118: } else {
1.223 djm 2119: if (deadline > INT_MAX / 1000)
2120: *timeoutp = INT_MAX / 1000;
2121: else
2122: *timeoutp = deadline * 1000;
1.155 dtucker 2123: }
1.46 markus 2124: return (1);
1.21 markus 2125: }
2126:
1.55 itojun 2127: static void
1.113 markus 2128: cleanup_socket(void)
1.15 markus 2129: {
1.187 djm 2130: if (cleanup_pid != 0 && getpid() != cleanup_pid)
2131: return;
1.266 djm 2132: debug_f("cleanup");
1.48 deraadt 2133: if (socket_name[0])
2134: unlink(socket_name);
2135: if (socket_dir[0])
2136: rmdir(socket_dir);
1.10 markus 2137: }
2138:
1.114 markus 2139: void
1.15 markus 2140: cleanup_exit(int i)
2141: {
1.113 markus 2142: cleanup_socket();
2143: _exit(i);
1.15 markus 2144: }
2145:
1.55 itojun 2146: static void
1.48 deraadt 2147: cleanup_handler(int sig)
2148: {
1.113 markus 2149: cleanup_socket();
1.163 markus 2150: #ifdef ENABLE_PKCS11
2151: pkcs11_terminate();
2152: #endif
1.48 deraadt 2153: _exit(2);
1.113 markus 2154: }
2155:
1.68 markus 2156: static void
1.155 dtucker 2157: check_parent_exists(void)
1.68 markus 2158: {
1.172 dtucker 2159: /*
2160: * If our parent has exited then getppid() will return (pid_t)1,
2161: * so testing for that should be safe.
2162: */
2163: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 2164: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 2165: cleanup_socket();
2166: _exit(2);
1.68 markus 2167: }
1.48 deraadt 2168: }
2169:
1.55 itojun 2170: static void
1.50 itojun 2171: usage(void)
1.15 markus 2172: {
1.184 deraadt 2173: fprintf(stderr,
1.250 jmc 2174: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.293 jmc 2175: " [-O option] [-P allowed_providers] [-t life]\n"
2176: " ssh-agent [-a bind_address] [-E fingerprint_hash] [-O option]\n"
2177: " [-P allowed_providers] [-t life] command [arg ...]\n"
1.250 jmc 2178: " ssh-agent [-c | -s] -k\n");
1.21 markus 2179: exit(1);
1.15 markus 2180: }
2181:
1.2 provos 2182: int
2183: main(int ac, char **av)
1.1 deraadt 2184: {
1.201 djm 2185: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.265 djm 2186: int sock, ch, result, saved_errno;
1.96 deraadt 2187: char *shell, *format, *pidstr, *agentsocket = NULL;
1.41 markus 2188: struct rlimit rlim;
1.96 deraadt 2189: extern int optind;
1.98 stevesk 2190: extern char *optarg;
1.21 markus 2191: pid_t pid;
1.96 deraadt 2192: char pidstrbuf[1 + 3 * sizeof pid];
1.161 tobias 2193: size_t len;
1.189 djm 2194: mode_t prev_mask;
1.224 djm 2195: int timeout = -1; /* INFTIM */
1.223 djm 2196: struct pollfd *pfd = NULL;
2197: size_t npfd = 0;
1.231 djm 2198: u_int maxfds;
1.123 djm 2199:
2200: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
2201: sanitise_stdfd();
1.99 markus 2202:
2203: /* drop */
1.298 dtucker 2204: (void)setegid(getgid());
2205: (void)setgid(getgid());
1.53 markus 2206:
1.231 djm 2207: if (getrlimit(RLIMIT_NOFILE, &rlim) == -1)
2208: fatal("%s: getrlimit: %s", __progname, strerror(errno));
2209:
1.185 markus 2210: #ifdef WITH_OPENSSL
1.170 djm 2211: OpenSSL_add_all_algorithms();
1.185 markus 2212: #endif
1.21 markus 2213:
1.258 djm 2214: while ((ch = getopt(ac, av, "cDdksE:a:O:P:t:")) != -1) {
1.21 markus 2215: switch (ch) {
1.192 djm 2216: case 'E':
2217: fingerprint_hash = ssh_digest_alg_by_name(optarg);
2218: if (fingerprint_hash == -1)
2219: fatal("Invalid hash algorithm \"%s\"", optarg);
2220: break;
1.21 markus 2221: case 'c':
2222: if (s_flag)
2223: usage();
2224: c_flag++;
2225: break;
2226: case 'k':
2227: k_flag++;
1.258 djm 2228: break;
2229: case 'O':
2230: if (strcmp(optarg, "no-restrict-websafe") == 0)
1.300 djm 2231: restrict_websafe = 0;
2232: else if (strcmp(optarg, "allow-remote-pkcs11") == 0)
2233: remote_add_provider = 1;
1.258 djm 2234: else
2235: fatal("Unknown -O option");
1.21 markus 2236: break;
1.215 djm 2237: case 'P':
1.260 djm 2238: if (allowed_providers != NULL)
1.215 djm 2239: fatal("-P option already specified");
1.260 djm 2240: allowed_providers = xstrdup(optarg);
1.215 djm 2241: break;
1.21 markus 2242: case 's':
2243: if (c_flag)
2244: usage();
2245: s_flag++;
2246: break;
1.57 markus 2247: case 'd':
1.201 djm 2248: if (d_flag || D_flag)
1.57 markus 2249: usage();
2250: d_flag++;
2251: break;
1.201 djm 2252: case 'D':
2253: if (d_flag || D_flag)
2254: usage();
2255: D_flag++;
2256: break;
1.86 markus 2257: case 'a':
2258: agentsocket = optarg;
1.106 marc 2259: break;
2260: case 't':
2261: if ((lifetime = convtime(optarg)) == -1) {
2262: fprintf(stderr, "Invalid lifetime\n");
2263: usage();
2264: }
1.86 markus 2265: break;
1.21 markus 2266: default:
2267: usage();
2268: }
2269: }
2270: ac -= optind;
2271: av += optind;
2272:
1.201 djm 2273: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 2274: usage();
2275:
1.260 djm 2276: if (allowed_providers == NULL)
1.262 djm 2277: allowed_providers = xstrdup(DEFAULT_ALLOWED_PROVIDERS);
1.215 djm 2278:
1.85 markus 2279: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 2280: shell = getenv("SHELL");
1.161 tobias 2281: if (shell != NULL && (len = strlen(shell)) > 2 &&
2282: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 2283: c_flag = 1;
2284: }
2285: if (k_flag) {
1.136 deraadt 2286: const char *errstr = NULL;
2287:
1.21 markus 2288: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
2289: if (pidstr == NULL) {
2290: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 2291: SSH_AGENTPID_ENV_NAME);
1.21 markus 2292: exit(1);
2293: }
1.136 deraadt 2294: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
2295: if (errstr) {
2296: fprintf(stderr,
2297: "%s=\"%s\", which is not a good PID: %s\n",
2298: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 2299: exit(1);
2300: }
2301: if (kill(pid, SIGTERM) == -1) {
2302: perror("kill");
2303: exit(1);
2304: }
2305: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 2306: printf(format, SSH_AUTHSOCKET_ENV_NAME);
2307: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 2308: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 2309: exit(0);
2310: }
1.231 djm 2311:
2312: /*
2313: * Minimum file descriptors:
2314: * stdio (3) + listener (1) + syslog (1 maybe) + connection (1) +
2315: * a few spare for libc / stack protectors / sanitisers, etc.
2316: */
2317: #define SSH_AGENT_MIN_FDS (3+1+1+1+4)
2318: if (rlim.rlim_cur < SSH_AGENT_MIN_FDS)
1.232 djm 2319: fatal("%s: file descriptor rlimit %lld too low (minimum %u)",
1.231 djm 2320: __progname, (long long)rlim.rlim_cur, SSH_AGENT_MIN_FDS);
2321: maxfds = rlim.rlim_cur - SSH_AGENT_MIN_FDS;
2322:
1.21 markus 2323: parent_pid = getpid();
2324:
1.86 markus 2325: if (agentsocket == NULL) {
2326: /* Create private directory for agent socket */
1.171 djm 2327: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 2328: if (mkdtemp(socket_dir) == NULL) {
2329: perror("mkdtemp: private socket dir");
2330: exit(1);
2331: }
1.91 mpech 2332: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
2333: (long)parent_pid);
1.86 markus 2334: } else {
2335: /* Try to use specified agent socket */
2336: socket_dir[0] = '\0';
2337: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 2338: }
2339:
1.23 markus 2340: /*
2341: * Create socket early so it will exist before command gets run from
2342: * the parent.
2343: */
1.189 djm 2344: prev_mask = umask(0177);
1.188 millert 2345: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 2346: if (sock < 0) {
1.188 millert 2347: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 2348: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 2349: cleanup_exit(1);
2350: }
1.189 djm 2351: umask(prev_mask);
1.46 markus 2352:
1.23 markus 2353: /*
2354: * Fork, and have the parent execute the command, if any, or present
2355: * the socket data. The child continues as the authentication agent.
2356: */
1.201 djm 2357: if (D_flag || d_flag) {
2358: log_init(__progname,
2359: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
2360: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 2361: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
2362: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
2363: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 2364: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 2365: fflush(stdout);
1.57 markus 2366: goto skip;
2367: }
1.21 markus 2368: pid = fork();
2369: if (pid == -1) {
2370: perror("fork");
1.81 stevesk 2371: cleanup_exit(1);
1.21 markus 2372: }
2373: if (pid != 0) { /* Parent - execute the given command. */
2374: close(sock);
1.91 mpech 2375: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 2376: if (ac == 0) {
2377: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
2378: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 2379: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 2380: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 2381: SSH_AGENTPID_ENV_NAME);
1.91 mpech 2382: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 2383: exit(0);
2384: }
1.36 deraadt 2385: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
2386: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
2387: perror("setenv");
2388: exit(1);
2389: }
1.21 markus 2390: execvp(av[0], av);
2391: perror(av[0]);
2392: exit(1);
2393: }
1.81 stevesk 2394: /* child */
2395: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 2396:
2397: if (setsid() == -1) {
1.81 stevesk 2398: error("setsid: %s", strerror(errno));
1.67 stevesk 2399: cleanup_exit(1);
2400: }
2401:
2402: (void)chdir("/");
1.265 djm 2403: if (stdfd_devnull(1, 1, 1) == -1)
1.266 djm 2404: error_f("stdfd_devnull failed");
1.21 markus 2405:
1.41 markus 2406: /* deny core dumps, since memory contains unencrypted private keys */
2407: rlim.rlim_cur = rlim.rlim_max = 0;
1.237 deraadt 2408: if (setrlimit(RLIMIT_CORE, &rlim) == -1) {
1.81 stevesk 2409: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 2410: cleanup_exit(1);
2411: }
1.57 markus 2412:
2413: skip:
1.187 djm 2414:
2415: cleanup_pid = getpid();
1.163 markus 2416:
2417: #ifdef ENABLE_PKCS11
2418: pkcs11_init(0);
2419: #endif
1.21 markus 2420: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 2421: if (ac > 0)
2422: parent_alive_interval = 10;
1.33 markus 2423: idtab_init();
1.252 dtucker 2424: ssh_signal(SIGPIPE, SIG_IGN);
2425: ssh_signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
2426: ssh_signal(SIGHUP, cleanup_handler);
2427: ssh_signal(SIGTERM, cleanup_handler);
1.205 djm 2428:
1.215 djm 2429: if (pledge("stdio rpath cpath unix id proc exec", NULL) == -1)
1.205 djm 2430: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 2431:
1.21 markus 2432: while (1) {
1.231 djm 2433: prepare_poll(&pfd, &npfd, &timeout, maxfds);
1.223 djm 2434: result = poll(pfd, npfd, timeout);
1.154 dtucker 2435: saved_errno = errno;
1.155 dtucker 2436: if (parent_alive_interval != 0)
2437: check_parent_exists();
2438: (void) reaper(); /* remove expired keys */
1.237 deraadt 2439: if (result == -1) {
1.154 dtucker 2440: if (saved_errno == EINTR)
1.21 markus 2441: continue;
1.223 djm 2442: fatal("poll: %s", strerror(saved_errno));
1.154 dtucker 2443: } else if (result > 0)
1.231 djm 2444: after_poll(pfd, npfd, maxfds);
1.15 markus 2445: }
1.21 markus 2446: /* NOTREACHED */
1.1 deraadt 2447: }
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