Annotation of src/usr.bin/ssh/ssh-agent.c, Revision 1.288
1.288 ! djm 1: /* $OpenBSD: ssh-agent.c,v 1.287 2022/01/14 03:43:48 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"
1.37 markus 70: #include "compat.h"
1.47 markus 71: #include "log.h"
1.107 markus 72: #include "misc.h"
1.182 markus 73: #include "digest.h"
1.194 markus 74: #include "ssherr.h"
1.215 djm 75: #include "match.h"
1.238 djm 76: #include "msg.h"
1.244 djm 77: #include "ssherr.h"
1.238 djm 78: #include "pathnames.h"
1.163 markus 79: #include "ssh-pkcs11.h"
1.251 djm 80: #include "sk-api.h"
1.281 djm 81: #include "myproposal.h"
1.59 markus 82:
1.262 djm 83: #ifndef DEFAULT_ALLOWED_PROVIDERS
84: # define DEFAULT_ALLOWED_PROVIDERS "/usr/lib*/*,/usr/local/lib*/*"
1.215 djm 85: #endif
86:
1.223 djm 87: /* Maximum accepted message length */
1.280 djm 88: #define AGENT_MAX_LEN (256*1024)
1.233 djm 89: /* Maximum bytes to read from client socket */
1.280 djm 90: #define AGENT_RBUF_LEN (4096)
91: /* Maximum number of recorded session IDs/hostkeys per connection */
92: #define AGENT_MAX_SESSION_IDS 16
93: /* Maximum size of session ID */
94: #define AGENT_MAX_SID_LEN 128
1.281 djm 95: /* Maximum number of destination constraints to accept on a key */
96: #define AGENT_MAX_DEST_CONSTRAINTS 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;
1.1 deraadt 120: } SocketEntry;
121:
1.45 markus 122: u_int sockets_alloc = 0;
1.1 deraadt 123: SocketEntry *sockets = NULL;
124:
1.78 provos 125: typedef struct identity {
126: TAILQ_ENTRY(identity) next;
1.194 markus 127: struct sshkey *key;
1.21 markus 128: char *comment;
1.163 markus 129: char *provider;
1.174 dtucker 130: time_t death;
1.107 markus 131: u_int confirm;
1.238 djm 132: char *sk_provider;
1.281 djm 133: struct dest_constraint *dest_constraints;
134: size_t ndest_constraints;
1.1 deraadt 135: } Identity;
136:
1.221 djm 137: struct idtable {
1.33 markus 138: int nentries;
1.78 provos 139: TAILQ_HEAD(idqueue, identity) idlist;
1.221 djm 140: };
1.33 markus 141:
1.221 djm 142: /* private key table */
143: struct idtable *idtab;
1.1 deraadt 144:
145: int max_fd = 0;
146:
1.11 markus 147: /* pid of shell == parent of agent */
1.29 deraadt 148: pid_t parent_pid = -1;
1.176 dtucker 149: time_t parent_alive_interval = 0;
1.10 markus 150:
1.187 djm 151: /* pid of process for which cleanup_socket is applicable */
152: pid_t cleanup_pid = 0;
153:
1.10 markus 154: /* pathname and directory for AUTH_SOCKET */
1.196 deraadt 155: char socket_name[PATH_MAX];
156: char socket_dir[PATH_MAX];
1.10 markus 157:
1.260 djm 158: /* Pattern-list of allowed PKCS#11/Security key paths */
159: static char *allowed_providers;
1.215 djm 160:
1.88 markus 161: /* locking */
1.203 dtucker 162: #define LOCK_SIZE 32
163: #define LOCK_SALT_SIZE 16
164: #define LOCK_ROUNDS 1
1.88 markus 165: int locked = 0;
1.213 djm 166: u_char lock_pwhash[LOCK_SIZE];
167: u_char lock_salt[LOCK_SALT_SIZE];
1.88 markus 168:
1.20 markus 169: extern char *__progname;
170:
1.174 dtucker 171: /* Default lifetime in seconds (0 == forever) */
1.268 dtucker 172: static int lifetime = 0;
1.106 marc 173:
1.192 djm 174: static int fingerprint_hash = SSH_FP_HASH_DEFAULT;
175:
1.258 djm 176: /* Refuse signing of non-SSH messages for web-origin FIDO keys */
177: static int restrict_websafe = 1;
178:
1.55 itojun 179: static void
1.101 stevesk 180: close_socket(SocketEntry *e)
181: {
1.280 djm 182: size_t i;
183:
1.101 stevesk 184: close(e->fd);
1.194 markus 185: sshbuf_free(e->input);
186: sshbuf_free(e->output);
187: sshbuf_free(e->request);
1.280 djm 188: for (i = 0; i < e->nsession_ids; i++) {
189: sshkey_free(e->session_ids[i].key);
190: sshbuf_free(e->session_ids[i].sid);
191: }
192: free(e->session_ids);
1.269 djm 193: memset(e, '\0', sizeof(*e));
194: e->fd = -1;
195: e->type = AUTH_UNUSED;
1.101 stevesk 196: }
197:
198: static void
1.33 markus 199: idtab_init(void)
1.1 deraadt 200: {
1.221 djm 201: idtab = xcalloc(1, sizeof(*idtab));
202: TAILQ_INIT(&idtab->idlist);
203: idtab->nentries = 0;
1.33 markus 204: }
205:
1.89 markus 206: static void
1.281 djm 207: free_dest_constraint_hop(struct dest_constraint_hop *dch)
208: {
209: u_int i;
210:
211: if (dch == NULL)
212: return;
213: free(dch->user);
214: free(dch->hostname);
215: for (i = 0; i < dch->nkeys; i++)
216: sshkey_free(dch->keys[i]);
217: free(dch->keys);
218: free(dch->key_is_ca);
219: }
220:
221: static void
222: free_dest_constraints(struct dest_constraint *dcs, size_t ndcs)
223: {
224: size_t i;
225:
226: for (i = 0; i < ndcs; i++) {
227: free_dest_constraint_hop(&dcs[i].from);
228: free_dest_constraint_hop(&dcs[i].to);
229: }
230: free(dcs);
231: }
232:
233: static void
1.89 markus 234: free_identity(Identity *id)
235: {
1.194 markus 236: sshkey_free(id->key);
1.173 djm 237: free(id->provider);
238: free(id->comment);
1.238 djm 239: free(id->sk_provider);
1.281 djm 240: free_dest_constraints(id->dest_constraints, id->ndest_constraints);
1.173 djm 241: free(id);
1.89 markus 242: }
243:
1.281 djm 244: /*
245: * Match 'key' against the key/CA list in a destination constraint hop
246: * Returns 0 on success or -1 otherwise.
247: */
248: static int
249: match_key_hop(const char *tag, const struct sshkey *key,
250: const struct dest_constraint_hop *dch)
251: {
252: const char *reason = NULL;
1.286 dtucker 253: const char *hostname = dch->hostname ? dch->hostname : "(ORIGIN)";
1.281 djm 254: u_int i;
255: char *fp;
256:
257: if (key == NULL)
258: return -1;
259: /* XXX logspam */
260: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
261: SSH_FP_DEFAULT)) == NULL)
262: fatal_f("fingerprint failed");
263: debug3_f("%s: entering hostname %s, requested key %s %s, %u keys avail",
1.286 dtucker 264: tag, hostname, sshkey_type(key), fp, dch->nkeys);
1.281 djm 265: free(fp);
266: for (i = 0; i < dch->nkeys; i++) {
267: if (dch->keys[i] == NULL)
268: return -1;
269: /* XXX logspam */
270: if ((fp = sshkey_fingerprint(dch->keys[i], SSH_FP_HASH_DEFAULT,
271: SSH_FP_DEFAULT)) == NULL)
272: fatal_f("fingerprint failed");
273: debug3_f("%s: key %u: %s%s %s", tag, i,
274: dch->key_is_ca[i] ? "CA " : "",
275: sshkey_type(dch->keys[i]), fp);
276: free(fp);
277: if (!sshkey_is_cert(key)) {
278: /* plain key */
279: if (dch->key_is_ca[i] ||
280: !sshkey_equal(key, dch->keys[i]))
281: continue;
282: return 0;
283: }
284: /* certificate */
285: if (!dch->key_is_ca[i])
286: continue;
287: if (key->cert == NULL || key->cert->signature_key == NULL)
288: return -1; /* shouldn't happen */
289: if (!sshkey_equal(key->cert->signature_key, dch->keys[i]))
290: continue;
1.286 dtucker 291: if (sshkey_cert_check_host(key, hostname, 1,
1.281 djm 292: SSH_ALLOWED_CA_SIGALGS, &reason) != 0) {
293: debug_f("cert %s / hostname %s rejected: %s",
1.286 dtucker 294: key->cert->key_id, hostname, reason);
1.281 djm 295: continue;
296: }
297: return 0;
298: }
299: return -1;
300: }
301:
302: /* Check destination constraints on an identity against the hostkey/user */
303: static int
304: permitted_by_dest_constraints(const struct sshkey *fromkey,
305: const struct sshkey *tokey, Identity *id, const char *user,
306: const char **hostnamep)
307: {
308: size_t i;
309: struct dest_constraint *d;
310:
311: if (hostnamep != NULL)
312: *hostnamep = NULL;
313: for (i = 0; i < id->ndest_constraints; i++) {
314: d = id->dest_constraints + i;
315: /* XXX remove logspam */
316: debug2_f("constraint %zu %s%s%s (%u keys) > %s%s%s (%u keys)",
317: i, d->from.user ? d->from.user : "",
318: d->from.user ? "@" : "",
319: d->from.hostname ? d->from.hostname : "(ORIGIN)",
320: d->from.nkeys,
321: d->to.user ? d->to.user : "", d->to.user ? "@" : "",
322: d->to.hostname ? d->to.hostname : "(ANY)", d->to.nkeys);
323:
324: /* Match 'from' key */
325: if (fromkey == NULL) {
326: /* We are matching the first hop */
327: if (d->from.hostname != NULL || d->from.nkeys != 0)
328: continue;
329: } else if (match_key_hop("from", fromkey, &d->from) != 0)
330: continue;
331:
332: /* Match 'to' key */
333: if (tokey != NULL && match_key_hop("to", tokey, &d->to) != 0)
334: continue;
335:
336: /* Match user if specified */
337: if (d->to.user != NULL && user != NULL &&
338: !match_pattern(user, d->to.user))
339: continue;
340:
341: /* successfully matched this constraint */
342: if (hostnamep != NULL)
343: *hostnamep = d->to.hostname;
344: debug2_f("allowed for hostname %s",
345: d->to.hostname == NULL ? "*" : d->to.hostname);
346: return 0;
347: }
348: /* no match */
349: debug2_f("%s identity \"%s\" not permitted for this destination",
350: sshkey_type(id->key), id->comment);
351: return -1;
352: }
353:
354: /*
355: * Check whether hostkeys on a SocketEntry and the optionally specified user
356: * are permitted by the destination constraints on the Identity.
357: * Returns 0 on success or -1 otherwise.
358: */
359: static int
360: identity_permitted(Identity *id, SocketEntry *e, char *user,
361: const char **forward_hostnamep, const char **last_hostnamep)
362: {
363: size_t i;
364: const char **hp;
365: struct hostkey_sid *hks;
366: const struct sshkey *fromkey = NULL;
367: const char *test_user;
368: char *fp1, *fp2;
369:
370: /* XXX remove logspam */
371: debug3_f("entering: key %s comment \"%s\", %zu socket bindings, "
372: "%zu constraints", sshkey_type(id->key), id->comment,
373: e->nsession_ids, id->ndest_constraints);
374: if (id->ndest_constraints == 0)
375: return 0; /* unconstrained */
376: if (e->nsession_ids == 0)
377: return 0; /* local use */
378: /*
379: * Walk through the hops recorded by session_id and try to find a
380: * constraint that satisfies each.
381: */
382: for (i = 0; i < e->nsession_ids; i++) {
383: hks = e->session_ids + i;
384: if (hks->key == NULL)
385: fatal_f("internal error: no bound key");
386: /* XXX remove logspam */
387: fp1 = fp2 = NULL;
388: if (fromkey != NULL &&
389: (fp1 = sshkey_fingerprint(fromkey, SSH_FP_HASH_DEFAULT,
390: SSH_FP_DEFAULT)) == NULL)
391: fatal_f("fingerprint failed");
392: if ((fp2 = sshkey_fingerprint(hks->key, SSH_FP_HASH_DEFAULT,
393: SSH_FP_DEFAULT)) == NULL)
394: fatal_f("fingerprint failed");
395: debug3_f("socketentry fd=%d, entry %zu %s, "
396: "from hostkey %s %s to user %s hostkey %s %s",
397: e->fd, i, hks->forwarded ? "FORWARD" : "AUTH",
398: fromkey ? sshkey_type(fromkey) : "(ORIGIN)",
399: fromkey ? fp1 : "", user ? user : "(ANY)",
400: sshkey_type(hks->key), fp2);
401: free(fp1);
402: free(fp2);
403: /*
404: * Record the hostnames for the initial forwarding and
405: * the final destination.
406: */
407: hp = NULL;
408: if (i == e->nsession_ids - 1)
409: hp = last_hostnamep;
410: else if (i == 0)
411: hp = forward_hostnamep;
412: /* Special handling for final recorded binding */
413: test_user = NULL;
414: if (i == e->nsession_ids - 1) {
415: /* Can only check user at final hop */
416: test_user = user;
417: /*
418: * user is only presented for signature requests.
419: * If this is the case, make sure last binding is not
420: * for a forwarding.
421: */
422: if (hks->forwarded && user != NULL) {
423: error_f("tried to sign on forwarding hop");
424: return -1;
425: }
426: } else if (!hks->forwarded) {
427: error_f("tried to forward though signing bind");
428: return -1;
429: }
430: if (permitted_by_dest_constraints(fromkey, hks->key, id,
431: test_user, hp) != 0)
432: return -1;
433: fromkey = hks->key;
434: }
435: /*
436: * Another special case: if the last bound session ID was for a
437: * forwarding, and this function is not being called to check a sign
438: * request (i.e. no 'user' supplied), then only permit the key if
439: * there is a permission that would allow it to be used at another
440: * destination. This hides keys that are allowed to be used to
1.284 jsg 441: * authenticate *to* a host but not permitted for *use* beyond it.
1.281 djm 442: */
443: hks = &e->session_ids[e->nsession_ids - 1];
444: if (hks->forwarded && user == NULL &&
445: permitted_by_dest_constraints(hks->key, NULL, id,
446: NULL, NULL) != 0) {
447: debug3_f("key permitted at host but not after");
448: return -1;
449: }
450:
451: /* success */
452: return 0;
453: }
454:
1.33 markus 455: /* return matching private key for given public key */
1.78 provos 456: static Identity *
1.221 djm 457: lookup_identity(struct sshkey *key)
1.33 markus 458: {
1.78 provos 459: Identity *id;
460:
1.221 djm 461: TAILQ_FOREACH(id, &idtab->idlist, next) {
1.194 markus 462: if (sshkey_equal(key, id->key))
1.78 provos 463: return (id);
1.33 markus 464: }
1.78 provos 465: return (NULL);
466: }
467:
1.107 markus 468: /* Check confirmation of keysign request */
469: static int
1.270 djm 470: confirm_key(Identity *id, const char *extra)
1.107 markus 471: {
1.122 djm 472: char *p;
1.107 markus 473: int ret = -1;
474:
1.194 markus 475: p = sshkey_fingerprint(id->key, fingerprint_hash, SSH_FP_DEFAULT);
1.197 djm 476: if (p != NULL &&
1.270 djm 477: ask_permission("Allow use of key %s?\nKey fingerprint %s.%s%s",
478: id->comment, p,
479: extra == NULL ? "" : "\n", extra == NULL ? "" : extra))
1.122 djm 480: ret = 0;
1.173 djm 481: free(p);
1.122 djm 482:
1.107 markus 483: return (ret);
484: }
485:
1.194 markus 486: static void
487: send_status(SocketEntry *e, int success)
488: {
489: int r;
490:
491: if ((r = sshbuf_put_u32(e->output, 1)) != 0 ||
492: (r = sshbuf_put_u8(e->output, success ?
493: SSH_AGENT_SUCCESS : SSH_AGENT_FAILURE)) != 0)
1.266 djm 494: fatal_fr(r, "compose");
1.194 markus 495: }
496:
1.33 markus 497: /* send list of supported public keys to 'client' */
1.55 itojun 498: static void
1.221 djm 499: process_request_identities(SocketEntry *e)
1.33 markus 500: {
1.96 deraadt 501: Identity *id;
1.281 djm 502: struct sshbuf *msg, *keys;
1.194 markus 503: int r;
1.281 djm 504: u_int nentries = 0;
1.1 deraadt 505:
1.269 djm 506: debug2_f("entering");
507:
1.281 djm 508: if ((msg = sshbuf_new()) == NULL || (keys = sshbuf_new()) == NULL)
1.266 djm 509: fatal_f("sshbuf_new failed");
1.221 djm 510: TAILQ_FOREACH(id, &idtab->idlist, next) {
1.281 djm 511: /* identity not visible, don't include in response */
512: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
513: continue;
514: if ((r = sshkey_puts_opts(id->key, keys,
1.278 djm 515: SSHKEY_SERIALIZE_INFO)) != 0 ||
1.281 djm 516: (r = sshbuf_put_cstring(keys, id->comment)) != 0) {
1.266 djm 517: error_fr(r, "compose key/comment");
1.220 djm 518: continue;
1.33 markus 519: }
1.281 djm 520: nentries++;
1.21 markus 521: }
1.281 djm 522: debug2_f("replying with %u allowed of %u available keys",
523: nentries, idtab->nentries);
524: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
525: (r = sshbuf_put_u32(msg, nentries)) != 0 ||
526: (r = sshbuf_putb(msg, keys)) != 0)
527: fatal_fr(r, "compose");
1.194 markus 528: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 529: fatal_fr(r, "enqueue");
1.194 markus 530: sshbuf_free(msg);
1.281 djm 531: sshbuf_free(keys);
1.1 deraadt 532: }
533:
1.33 markus 534:
1.208 markus 535: static char *
536: agent_decode_alg(struct sshkey *key, u_int flags)
537: {
538: if (key->type == KEY_RSA) {
539: if (flags & SSH_AGENT_RSA_SHA2_256)
540: return "rsa-sha2-256";
541: else if (flags & SSH_AGENT_RSA_SHA2_512)
542: return "rsa-sha2-512";
1.235 djm 543: } else if (key->type == KEY_RSA_CERT) {
544: if (flags & SSH_AGENT_RSA_SHA2_256)
545: return "rsa-sha2-256-cert-v01@openssh.com";
546: else if (flags & SSH_AGENT_RSA_SHA2_512)
547: return "rsa-sha2-512-cert-v01@openssh.com";
1.208 markus 548: }
549: return NULL;
550: }
551:
1.258 djm 552: /*
1.270 djm 553: * Attempt to parse the contents of a buffer as a SSH publickey userauth
554: * request, checking its contents for consistency and matching the embedded
555: * key against the one that is being used for signing.
556: * Note: does not modify msg buffer.
1.282 djm 557: * Optionally extract the username, session ID and/or hostkey from the request.
1.258 djm 558: */
559: static int
1.270 djm 560: parse_userauth_request(struct sshbuf *msg, const struct sshkey *expected_key,
1.282 djm 561: char **userp, struct sshbuf **sess_idp, struct sshkey **hostkeyp)
1.258 djm 562: {
1.270 djm 563: struct sshbuf *b = NULL, *sess_id = NULL;
564: char *user = NULL, *service = NULL, *method = NULL, *pkalg = NULL;
1.258 djm 565: int r;
1.270 djm 566: u_char t, sig_follows;
1.282 djm 567: struct sshkey *mkey = NULL, *hostkey = NULL;
1.258 djm 568:
1.270 djm 569: if (userp != NULL)
570: *userp = NULL;
571: if (sess_idp != NULL)
572: *sess_idp = NULL;
1.282 djm 573: if (hostkeyp != NULL)
574: *hostkeyp = NULL;
1.270 djm 575: if ((b = sshbuf_fromb(msg)) == NULL)
576: fatal_f("sshbuf_fromb");
1.258 djm 577:
578: /* SSH userauth request */
1.270 djm 579: if ((r = sshbuf_froms(b, &sess_id)) != 0)
580: goto out;
581: if (sshbuf_len(sess_id) == 0) {
582: r = SSH_ERR_INVALID_FORMAT;
583: goto out;
584: }
585: if ((r = sshbuf_get_u8(b, &t)) != 0 || /* SSH2_MSG_USERAUTH_REQUEST */
586: (r = sshbuf_get_cstring(b, &user, NULL)) != 0 || /* server user */
587: (r = sshbuf_get_cstring(b, &service, NULL)) != 0 || /* service */
588: (r = sshbuf_get_cstring(b, &method, NULL)) != 0 || /* method */
589: (r = sshbuf_get_u8(b, &sig_follows)) != 0 || /* sig-follows */
590: (r = sshbuf_get_cstring(b, &pkalg, NULL)) != 0 || /* alg */
591: (r = sshkey_froms(b, &mkey)) != 0) /* key */
592: goto out;
593: if (t != SSH2_MSG_USERAUTH_REQUEST ||
594: sig_follows != 1 ||
595: strcmp(service, "ssh-connection") != 0 ||
596: !sshkey_equal(expected_key, mkey) ||
597: sshkey_type_from_name(pkalg) != expected_key->type) {
598: r = SSH_ERR_INVALID_FORMAT;
599: goto out;
600: }
1.282 djm 601: if (strcmp(method, "publickey-hostbound-v00@openssh.com") == 0) {
602: if ((r = sshkey_froms(b, &hostkey)) != 0)
603: goto out;
604: } else if (strcmp(method, "publickey") != 0) {
1.270 djm 605: r = SSH_ERR_INVALID_FORMAT;
606: goto out;
607: }
608: if (sshbuf_len(b) != 0) {
609: r = SSH_ERR_INVALID_FORMAT;
610: goto out;
611: }
612: /* success */
613: r = 0;
614: debug3_f("well formed userauth");
615: if (userp != NULL) {
616: *userp = user;
617: user = NULL;
618: }
619: if (sess_idp != NULL) {
620: *sess_idp = sess_id;
621: sess_id = NULL;
1.258 djm 622: }
1.282 djm 623: if (hostkeyp != NULL) {
624: *hostkeyp = hostkey;
625: hostkey = NULL;
626: }
1.270 djm 627: out:
628: sshbuf_free(b);
629: sshbuf_free(sess_id);
630: free(user);
631: free(service);
632: free(method);
633: free(pkalg);
1.258 djm 634: sshkey_free(mkey);
1.282 djm 635: sshkey_free(hostkey);
1.270 djm 636: return r;
637: }
638:
639: /*
640: * Attempt to parse the contents of a buffer as a SSHSIG signature request.
641: * Note: does not modify buffer.
642: */
643: static int
644: parse_sshsig_request(struct sshbuf *msg)
645: {
646: int r;
647: struct sshbuf *b;
648:
649: if ((b = sshbuf_fromb(msg)) == NULL)
650: fatal_f("sshbuf_fromb");
651:
652: if ((r = sshbuf_cmp(b, 0, "SSHSIG", 6)) != 0 ||
653: (r = sshbuf_consume(b, 6)) != 0 ||
654: (r = sshbuf_get_cstring(b, NULL, NULL)) != 0 || /* namespace */
655: (r = sshbuf_get_string_direct(b, NULL, NULL)) != 0 || /* reserved */
656: (r = sshbuf_get_cstring(b, NULL, NULL)) != 0 || /* hashalg */
657: (r = sshbuf_get_string_direct(b, NULL, NULL)) != 0) /* H(msg) */
658: goto out;
659: if (sshbuf_len(b) != 0) {
660: r = SSH_ERR_INVALID_FORMAT;
661: goto out;
662: }
663: /* success */
664: r = 0;
665: out:
1.258 djm 666: sshbuf_free(b);
1.270 djm 667: return r;
668: }
669:
670: /*
671: * This function inspects a message to be signed by a FIDO key that has a
672: * web-like application string (i.e. one that does not begin with "ssh:".
673: * It checks that the message is one of those expected for SSH operations
674: * (pubkey userauth, sshsig, CA key signing) to exclude signing challenges
675: * for the web.
676: */
677: static int
678: check_websafe_message_contents(struct sshkey *key, struct sshbuf *data)
679: {
1.282 djm 680: if (parse_userauth_request(data, key, NULL, NULL, NULL) == 0) {
1.270 djm 681: debug_f("signed data matches public key userauth request");
1.258 djm 682: return 1;
683: }
1.270 djm 684: if (parse_sshsig_request(data) == 0) {
685: debug_f("signed data matches SSHSIG signature request");
1.258 djm 686: return 1;
1.270 djm 687: }
1.258 djm 688:
1.270 djm 689: /* XXX check CA signature operation */
1.258 djm 690:
691: error("web-origin key attempting to sign non-SSH message");
692: return 0;
693: }
694:
1.280 djm 695: static int
696: buf_equal(const struct sshbuf *a, const struct sshbuf *b)
697: {
698: if (sshbuf_ptr(a) == NULL || sshbuf_ptr(b) == NULL)
699: return SSH_ERR_INVALID_ARGUMENT;
700: if (sshbuf_len(a) != sshbuf_len(b))
701: return SSH_ERR_INVALID_FORMAT;
702: if (timingsafe_bcmp(sshbuf_ptr(a), sshbuf_ptr(b), sshbuf_len(a)) != 0)
703: return SSH_ERR_INVALID_FORMAT;
704: return 0;
705: }
706:
1.33 markus 707: /* ssh2 only */
1.55 itojun 708: static void
1.33 markus 709: process_sign_request2(SocketEntry *e)
710: {
1.221 djm 711: u_char *signature = NULL;
1.281 djm 712: size_t slen = 0;
1.194 markus 713: u_int compat = 0, flags;
1.287 djm 714: int r, ok = -1, retried = 0;
715: char *fp = NULL, *pin = NULL, *prompt = NULL;
716: char *user = NULL, *sig_dest = NULL;
1.281 djm 717: const char *fwd_host = NULL, *dest_host = NULL;
1.280 djm 718: struct sshbuf *msg = NULL, *data = NULL, *sid = NULL;
1.283 djm 719: struct sshkey *key = NULL, *hostkey = NULL;
1.195 djm 720: struct identity *id;
1.251 djm 721: struct notifier_ctx *notifier = NULL;
1.194 markus 722:
1.270 djm 723: debug_f("entering");
724:
1.273 dtucker 725: if ((msg = sshbuf_new()) == NULL || (data = sshbuf_new()) == NULL)
1.266 djm 726: fatal_f("sshbuf_new failed");
1.221 djm 727: if ((r = sshkey_froms(e->request, &key)) != 0 ||
1.270 djm 728: (r = sshbuf_get_stringb(e->request, data)) != 0 ||
1.225 djm 729: (r = sshbuf_get_u32(e->request, &flags)) != 0) {
1.266 djm 730: error_fr(r, "parse");
1.225 djm 731: goto send;
732: }
733:
1.221 djm 734: if ((id = lookup_identity(key)) == NULL) {
1.266 djm 735: verbose_f("%s key not found", sshkey_type(key));
1.195 djm 736: goto send;
737: }
1.281 djm 738: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
739: SSH_FP_DEFAULT)) == NULL)
740: fatal_f("fingerprint failed");
741:
742: if (id->ndest_constraints != 0) {
743: if (e->nsession_ids == 0) {
744: logit_f("refusing use of destination-constrained key "
745: "to sign on unbound connection");
746: goto send;
747: }
1.283 djm 748: if (parse_userauth_request(data, key, &user, &sid,
749: &hostkey) != 0) {
1.281 djm 750: logit_f("refusing use of destination-constrained key "
751: "to sign an unidentified signature");
752: goto send;
753: }
754: /* XXX logspam */
755: debug_f("user=%s", user);
756: if (identity_permitted(id, e, user, &fwd_host, &dest_host) != 0)
757: goto send;
758: /* XXX display fwd_host/dest_host in askpass UI */
1.280 djm 759: /*
1.281 djm 760: * Ensure that the session ID is the most recent one
761: * registered on the socket - it should have been bound by
762: * ssh immediately before userauth.
1.280 djm 763: */
1.281 djm 764: if (buf_equal(sid,
765: e->session_ids[e->nsession_ids - 1].sid) != 0) {
766: error_f("unexpected session ID (%zu listed) on "
767: "signature request for target user %s with "
768: "key %s %s", e->nsession_ids, user,
769: sshkey_type(id->key), fp);
770: goto send;
1.280 djm 771: }
1.283 djm 772: /*
773: * Ensure that the hostkey embedded in the signature matches
774: * the one most recently bound to the socket. An exception is
775: * made for the initial forwarding hop.
776: */
777: if (e->nsession_ids > 1 && hostkey == NULL) {
778: error_f("refusing use of destination-constrained key: "
779: "no hostkey recorded in signature for forwarded "
780: "connection");
781: goto send;
782: }
783: if (hostkey != NULL && !sshkey_equal(hostkey,
784: e->session_ids[e->nsession_ids - 1].key)) {
785: error_f("refusing use of destination-constrained key: "
786: "mismatch between hostkey in request and most "
787: "recently bound session");
788: goto send;
789: }
1.281 djm 790: xasprintf(&sig_dest, "public key authentication request for "
791: "user \"%s\" to listed host", user);
1.280 djm 792: }
793: if (id->confirm && confirm_key(id, sig_dest) != 0) {
1.266 djm 794: verbose_f("user refused key");
1.195 djm 795: goto send;
796: }
1.258 djm 797: if (sshkey_is_sk(id->key)) {
798: if (strncmp(id->key->sk_application, "ssh:", 4) != 0 &&
1.270 djm 799: !check_websafe_message_contents(key, data)) {
1.258 djm 800: /* error already logged */
801: goto send;
802: }
1.287 djm 803: if ((id->key->sk_flags & SSH_SK_USER_VERIFICATION_REQD)) {
804: /* XXX include sig_dest */
805: xasprintf(&prompt, "Enter PIN%sfor %s key %s: ",
806: (id->key->sk_flags & SSH_SK_USER_PRESENCE_REQD) ?
807: " and confirm user presence " : " ",
808: sshkey_type(id->key), fp);
809: pin = read_passphrase(prompt, RP_USE_ASKPASS);
810: free(prompt);
811: prompt = NULL;
812: } else if ((id->key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1.258 djm 813: notifier = notify_start(0,
1.280 djm 814: "Confirm user presence for key %s %s%s%s",
815: sshkey_type(id->key), fp,
816: sig_dest == NULL ? "" : "\n",
817: sig_dest == NULL ? "" : sig_dest);
1.258 djm 818: }
1.251 djm 819: }
1.287 djm 820: retry_pin:
1.251 djm 821: if ((r = sshkey_sign(id->key, &signature, &slen,
1.270 djm 822: sshbuf_ptr(data), sshbuf_len(data), agent_decode_alg(key, flags),
1.287 djm 823: id->sk_provider, pin, compat)) != 0) {
824: debug_fr(r, "sshkey_sign");
825: if (pin == NULL && !retried && sshkey_is_sk(id->key) &&
826: r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
827: if (notifier) {
828: notify_complete(notifier, NULL);
829: notifier = NULL;
830: }
831: /* XXX include sig_dest */
832: xasprintf(&prompt, "Enter PIN%sfor %s key %s: ",
833: (id->key->sk_flags & SSH_SK_USER_PRESENCE_REQD) ?
834: " and confirm user presence " : " ",
835: sshkey_type(id->key), fp);
836: pin = read_passphrase(prompt, RP_USE_ASKPASS);
837: retried = 1;
838: goto retry_pin;
839: }
1.266 djm 840: error_fr(r, "sshkey_sign");
1.251 djm 841: goto send;
1.33 markus 842: }
1.195 djm 843: /* Success */
844: ok = 0;
845: send:
1.267 djm 846: notify_complete(notifier, "User presence confirmed");
1.270 djm 847:
1.33 markus 848: if (ok == 0) {
1.194 markus 849: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_SIGN_RESPONSE)) != 0 ||
850: (r = sshbuf_put_string(msg, signature, slen)) != 0)
1.266 djm 851: fatal_fr(r, "compose");
1.194 markus 852: } else if ((r = sshbuf_put_u8(msg, SSH_AGENT_FAILURE)) != 0)
1.266 djm 853: fatal_fr(r, "compose failure");
1.194 markus 854:
855: if ((r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 856: fatal_fr(r, "enqueue");
1.194 markus 857:
1.280 djm 858: sshbuf_free(sid);
1.270 djm 859: sshbuf_free(data);
1.194 markus 860: sshbuf_free(msg);
1.270 djm 861: sshkey_free(key);
1.283 djm 862: sshkey_free(hostkey);
1.270 djm 863: free(fp);
1.173 djm 864: free(signature);
1.280 djm 865: free(sig_dest);
866: free(user);
1.287 djm 867: free(prompt);
868: if (pin != NULL)
869: freezero(pin, strlen(pin));
1.1 deraadt 870: }
871:
1.33 markus 872: /* shared */
1.55 itojun 873: static void
1.221 djm 874: process_remove_identity(SocketEntry *e)
1.1 deraadt 875: {
1.194 markus 876: int r, success = 0;
877: struct sshkey *key = NULL;
1.221 djm 878: Identity *id;
1.21 markus 879:
1.269 djm 880: debug2_f("entering");
1.221 djm 881: if ((r = sshkey_froms(e->request, &key)) != 0) {
1.266 djm 882: error_fr(r, "parse key");
1.221 djm 883: goto done;
884: }
885: if ((id = lookup_identity(key)) == NULL) {
1.266 djm 886: debug_f("key not found");
1.221 djm 887: goto done;
888: }
1.281 djm 889: /* identity not visible, cannot be removed */
890: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
891: goto done; /* error already logged */
1.221 djm 892: /* We have this key, free it. */
893: if (idtab->nentries < 1)
1.266 djm 894: fatal_f("internal error: nentries %d", idtab->nentries);
1.221 djm 895: TAILQ_REMOVE(&idtab->idlist, id, next);
896: free_identity(id);
897: idtab->nentries--;
898: success = 1;
899: done:
1.276 djm 900: sshkey_free(key);
1.194 markus 901: send_status(e, success);
1.1 deraadt 902: }
903:
1.55 itojun 904: static void
1.221 djm 905: process_remove_all_identities(SocketEntry *e)
1.1 deraadt 906: {
1.78 provos 907: Identity *id;
1.21 markus 908:
1.269 djm 909: debug2_f("entering");
1.21 markus 910: /* Loop over all identities and clear the keys. */
1.221 djm 911: for (id = TAILQ_FIRST(&idtab->idlist); id;
912: id = TAILQ_FIRST(&idtab->idlist)) {
913: TAILQ_REMOVE(&idtab->idlist, id, next);
1.78 provos 914: free_identity(id);
1.21 markus 915: }
916:
917: /* Mark that there are no identities. */
1.221 djm 918: idtab->nentries = 0;
1.21 markus 919:
920: /* Send success. */
1.194 markus 921: send_status(e, 1);
1.1 deraadt 922: }
923:
1.155 dtucker 924: /* removes expired keys and returns number of seconds until the next expiry */
1.174 dtucker 925: static time_t
1.89 markus 926: reaper(void)
927: {
1.175 dtucker 928: time_t deadline = 0, now = monotime();
1.89 markus 929: Identity *id, *nxt;
930:
1.221 djm 931: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
932: nxt = TAILQ_NEXT(id, next);
933: if (id->death == 0)
934: continue;
935: if (now >= id->death) {
936: debug("expiring key '%s'", id->comment);
937: TAILQ_REMOVE(&idtab->idlist, id, next);
938: free_identity(id);
939: idtab->nentries--;
940: } else
941: deadline = (deadline == 0) ? id->death :
942: MINIMUM(deadline, id->death);
1.89 markus 943: }
1.155 dtucker 944: if (deadline == 0 || deadline <= now)
945: return 0;
946: else
947: return (deadline - now);
1.89 markus 948: }
949:
1.271 djm 950: static int
1.281 djm 951: parse_dest_constraint_hop(struct sshbuf *b, struct dest_constraint_hop *dch)
952: {
953: u_char key_is_ca;
954: size_t elen = 0;
955: int r;
956: struct sshkey *k = NULL;
957: char *fp;
958:
959: memset(dch, '\0', sizeof(*dch));
960: if ((r = sshbuf_get_cstring(b, &dch->user, NULL)) != 0 ||
961: (r = sshbuf_get_cstring(b, &dch->hostname, NULL)) != 0 ||
962: (r = sshbuf_get_string_direct(b, NULL, &elen)) != 0) {
963: error_fr(r, "parse");
964: goto out;
965: }
966: if (elen != 0) {
967: error_f("unsupported extensions (len %zu)", elen);
968: r = SSH_ERR_FEATURE_UNSUPPORTED;
969: goto out;
970: }
971: if (*dch->hostname == '\0') {
972: free(dch->hostname);
973: dch->hostname = NULL;
974: }
975: if (*dch->user == '\0') {
976: free(dch->user);
977: dch->user = NULL;
978: }
979: while (sshbuf_len(b) != 0) {
980: dch->keys = xrecallocarray(dch->keys, dch->nkeys,
981: dch->nkeys + 1, sizeof(*dch->keys));
982: dch->key_is_ca = xrecallocarray(dch->key_is_ca, dch->nkeys,
983: dch->nkeys + 1, sizeof(*dch->key_is_ca));
984: if ((r = sshkey_froms(b, &k)) != 0 ||
985: (r = sshbuf_get_u8(b, &key_is_ca)) != 0)
986: goto out;
987: if ((fp = sshkey_fingerprint(k, SSH_FP_HASH_DEFAULT,
988: SSH_FP_DEFAULT)) == NULL)
989: fatal_f("fingerprint failed");
990: debug3_f("%s%s%s: adding %skey %s %s",
991: dch->user == NULL ? "" : dch->user,
992: dch->user == NULL ? "" : "@",
993: dch->hostname, key_is_ca ? "CA " : "", sshkey_type(k), fp);
994: free(fp);
995: dch->keys[dch->nkeys] = k;
996: dch->key_is_ca[dch->nkeys] = key_is_ca != 0;
997: dch->nkeys++;
998: k = NULL; /* transferred */
999: }
1000: /* success */
1001: r = 0;
1002: out:
1003: sshkey_free(k);
1004: return r;
1005: }
1006:
1007: static int
1008: parse_dest_constraint(struct sshbuf *m, struct dest_constraint *dc)
1009: {
1010: struct sshbuf *b = NULL, *frombuf = NULL, *tobuf = NULL;
1011: int r;
1012: size_t elen = 0;
1013:
1014: debug3_f("entering");
1015:
1016: memset(dc, '\0', sizeof(*dc));
1017: if ((r = sshbuf_froms(m, &b)) != 0 ||
1018: (r = sshbuf_froms(b, &frombuf)) != 0 ||
1019: (r = sshbuf_froms(b, &tobuf)) != 0 ||
1020: (r = sshbuf_get_string_direct(b, NULL, &elen)) != 0) {
1021: error_fr(r, "parse");
1022: goto out;
1023: }
1024: if ((r = parse_dest_constraint_hop(frombuf, &dc->from) != 0) ||
1025: (r = parse_dest_constraint_hop(tobuf, &dc->to) != 0))
1026: goto out; /* already logged */
1027: if (elen != 0) {
1028: error_f("unsupported extensions (len %zu)", elen);
1029: r = SSH_ERR_FEATURE_UNSUPPORTED;
1030: goto out;
1031: }
1032: debug2_f("parsed %s (%u keys) > %s%s%s (%u keys)",
1033: dc->from.hostname ? dc->from.hostname : "(ORIGIN)", dc->from.nkeys,
1034: dc->to.user ? dc->to.user : "", dc->to.user ? "@" : "",
1035: dc->to.hostname ? dc->to.hostname : "(ANY)", dc->to.nkeys);
1036: /* check consistency */
1037: if ((dc->from.hostname == NULL) != (dc->from.nkeys == 0) ||
1038: dc->from.user != NULL) {
1039: error_f("inconsistent \"from\" specification");
1040: r = SSH_ERR_INVALID_FORMAT;
1041: goto out;
1042: }
1043: if (dc->to.hostname == NULL || dc->to.nkeys == 0) {
1044: error_f("incomplete \"to\" specification");
1045: r = SSH_ERR_INVALID_FORMAT;
1046: goto out;
1047: }
1048: /* success */
1049: r = 0;
1050: out:
1051: sshbuf_free(b);
1052: sshbuf_free(frombuf);
1053: sshbuf_free(tobuf);
1054: return r;
1055: }
1056:
1057: static int
1058: parse_key_constraint_extension(struct sshbuf *m, char **sk_providerp,
1059: struct dest_constraint **dcsp, size_t *ndcsp)
1.277 djm 1060: {
1061: char *ext_name = NULL;
1062: int r;
1.281 djm 1063: struct sshbuf *b = NULL;
1.277 djm 1064:
1065: if ((r = sshbuf_get_cstring(m, &ext_name, NULL)) != 0) {
1066: error_fr(r, "parse constraint extension");
1067: goto out;
1068: }
1069: debug_f("constraint ext %s", ext_name);
1070: if (strcmp(ext_name, "sk-provider@openssh.com") == 0) {
1071: if (sk_providerp == NULL) {
1072: error_f("%s not valid here", ext_name);
1073: r = SSH_ERR_INVALID_FORMAT;
1074: goto out;
1075: }
1076: if (*sk_providerp != NULL) {
1077: error_f("%s already set", ext_name);
1078: r = SSH_ERR_INVALID_FORMAT;
1079: goto out;
1080: }
1081: if ((r = sshbuf_get_cstring(m, sk_providerp, NULL)) != 0) {
1082: error_fr(r, "parse %s", ext_name);
1083: goto out;
1084: }
1.281 djm 1085: } else if (strcmp(ext_name,
1086: "restrict-destination-v00@openssh.com") == 0) {
1087: if (*dcsp != NULL) {
1088: error_f("%s already set", ext_name);
1089: goto out;
1090: }
1091: if ((r = sshbuf_froms(m, &b)) != 0) {
1092: error_fr(r, "parse %s outer", ext_name);
1093: goto out;
1094: }
1095: while (sshbuf_len(b) != 0) {
1096: if (*ndcsp >= AGENT_MAX_DEST_CONSTRAINTS) {
1097: error_f("too many %s constraints", ext_name);
1098: goto out;
1099: }
1100: *dcsp = xrecallocarray(*dcsp, *ndcsp, *ndcsp + 1,
1101: sizeof(**dcsp));
1102: if ((r = parse_dest_constraint(b,
1103: *dcsp + (*ndcsp)++)) != 0)
1104: goto out; /* error already logged */
1105: }
1.277 djm 1106: } else {
1107: error_f("unsupported constraint \"%s\"", ext_name);
1108: r = SSH_ERR_FEATURE_UNSUPPORTED;
1109: goto out;
1110: }
1111: /* success */
1112: r = 0;
1113: out:
1114: free(ext_name);
1.281 djm 1115: sshbuf_free(b);
1.277 djm 1116: return r;
1117: }
1118:
1119: static int
1.271 djm 1120: parse_key_constraints(struct sshbuf *m, struct sshkey *k, time_t *deathp,
1.281 djm 1121: u_int *secondsp, int *confirmp, char **sk_providerp,
1122: struct dest_constraint **dcsp, size_t *ndcsp)
1.1 deraadt 1123: {
1.194 markus 1124: u_char ctype;
1.271 djm 1125: int r;
1126: u_int seconds, maxsign = 0;
1.33 markus 1127:
1.271 djm 1128: while (sshbuf_len(m)) {
1129: if ((r = sshbuf_get_u8(m, &ctype)) != 0) {
1.266 djm 1130: error_fr(r, "parse constraint type");
1.277 djm 1131: goto out;
1.194 markus 1132: }
1133: switch (ctype) {
1.94 markus 1134: case SSH_AGENT_CONSTRAIN_LIFETIME:
1.271 djm 1135: if (*deathp != 0) {
1136: error_f("lifetime already set");
1.277 djm 1137: r = SSH_ERR_INVALID_FORMAT;
1138: goto out;
1.271 djm 1139: }
1140: if ((r = sshbuf_get_u32(m, &seconds)) != 0) {
1.266 djm 1141: error_fr(r, "parse lifetime constraint");
1.277 djm 1142: goto out;
1.194 markus 1143: }
1.271 djm 1144: *deathp = monotime() + seconds;
1145: *secondsp = seconds;
1.94 markus 1146: break;
1.107 markus 1147: case SSH_AGENT_CONSTRAIN_CONFIRM:
1.271 djm 1148: if (*confirmp != 0) {
1149: error_f("confirm already set");
1.277 djm 1150: r = SSH_ERR_INVALID_FORMAT;
1151: goto out;
1.271 djm 1152: }
1153: *confirmp = 1;
1.107 markus 1154: break;
1.228 markus 1155: case SSH_AGENT_CONSTRAIN_MAXSIGN:
1.271 djm 1156: if (k == NULL) {
1157: error_f("maxsign not valid here");
1.277 djm 1158: r = SSH_ERR_INVALID_FORMAT;
1159: goto out;
1.271 djm 1160: }
1161: if (maxsign != 0) {
1162: error_f("maxsign already set");
1.277 djm 1163: r = SSH_ERR_INVALID_FORMAT;
1164: goto out;
1.271 djm 1165: }
1166: if ((r = sshbuf_get_u32(m, &maxsign)) != 0) {
1.266 djm 1167: error_fr(r, "parse maxsign constraint");
1.277 djm 1168: goto out;
1.228 markus 1169: }
1170: if ((r = sshkey_enable_maxsign(k, maxsign)) != 0) {
1.266 djm 1171: error_fr(r, "enable maxsign");
1.277 djm 1172: goto out;
1.228 markus 1173: }
1174: break;
1.238 djm 1175: case SSH_AGENT_CONSTRAIN_EXTENSION:
1.277 djm 1176: if ((r = parse_key_constraint_extension(m,
1.281 djm 1177: sk_providerp, dcsp, ndcsp)) != 0)
1.277 djm 1178: goto out; /* error already logged */
1.238 djm 1179: break;
1.94 markus 1180: default:
1.266 djm 1181: error_f("Unknown constraint %d", ctype);
1.277 djm 1182: r = SSH_ERR_FEATURE_UNSUPPORTED;
1183: goto out;
1.94 markus 1184: }
1185: }
1.271 djm 1186: /* success */
1.277 djm 1187: r = 0;
1188: out:
1189: return r;
1.271 djm 1190: }
1191:
1192: static void
1193: process_add_identity(SocketEntry *e)
1194: {
1195: Identity *id;
1196: int success = 0, confirm = 0;
1.272 dtucker 1197: char *fp, *comment = NULL, *sk_provider = NULL;
1.271 djm 1198: char canonical_provider[PATH_MAX];
1199: time_t death = 0;
1200: u_int seconds = 0;
1.281 djm 1201: struct dest_constraint *dest_constraints = NULL;
1202: size_t ndest_constraints = 0;
1.271 djm 1203: struct sshkey *k = NULL;
1204: int r = SSH_ERR_INTERNAL_ERROR;
1205:
1206: debug2_f("entering");
1207: if ((r = sshkey_private_deserialize(e->request, &k)) != 0 ||
1208: k == NULL ||
1209: (r = sshbuf_get_cstring(e->request, &comment, NULL)) != 0) {
1210: error_fr(r, "parse");
1211: goto out;
1212: }
1213: if (parse_key_constraints(e->request, k, &death, &seconds, &confirm,
1.281 djm 1214: &sk_provider, &dest_constraints, &ndest_constraints) != 0) {
1.271 djm 1215: error_f("failed to parse constraints");
1216: sshbuf_reset(e->request);
1217: goto out;
1218: }
1219:
1.238 djm 1220: if (sk_provider != NULL) {
1.240 markus 1221: if (!sshkey_is_sk(k)) {
1.255 naddy 1222: error("Cannot add provider: %s is not an "
1223: "authenticator-hosted key", sshkey_type(k));
1.271 djm 1224: goto out;
1.238 djm 1225: }
1.254 djm 1226: if (strcasecmp(sk_provider, "internal") == 0) {
1.266 djm 1227: debug_f("internal provider");
1.254 djm 1228: } else {
1229: if (realpath(sk_provider, canonical_provider) == NULL) {
1230: verbose("failed provider \"%.100s\": "
1231: "realpath: %s", sk_provider,
1232: strerror(errno));
1.271 djm 1233: goto out;
1.254 djm 1234: }
1.238 djm 1235: free(sk_provider);
1.254 djm 1236: sk_provider = xstrdup(canonical_provider);
1237: if (match_pattern_list(sk_provider,
1.260 djm 1238: allowed_providers, 0) != 1) {
1.254 djm 1239: error("Refusing add key: "
1.260 djm 1240: "provider %s not allowed", sk_provider);
1.271 djm 1241: goto out;
1.254 djm 1242: }
1.238 djm 1243: }
1.242 markus 1244: }
1245: if ((r = sshkey_shield_private(k)) != 0) {
1.266 djm 1246: error_fr(r, "shield private");
1.271 djm 1247: goto out;
1.238 djm 1248: }
1.106 marc 1249: if (lifetime && !death)
1.175 dtucker 1250: death = monotime() + lifetime;
1.221 djm 1251: if ((id = lookup_identity(k)) == NULL) {
1.163 markus 1252: id = xcalloc(1, sizeof(Identity));
1.221 djm 1253: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
1.33 markus 1254: /* Increment the number of identities. */
1.221 djm 1255: idtab->nentries++;
1.33 markus 1256: } else {
1.281 djm 1257: /* identity not visible, do not update */
1258: if (identity_permitted(id, e, NULL, NULL, NULL) != 0)
1259: goto out; /* error already logged */
1.228 markus 1260: /* key state might have been updated */
1261: sshkey_free(id->key);
1.173 djm 1262: free(id->comment);
1.238 djm 1263: free(id->sk_provider);
1.281 djm 1264: free_dest_constraints(id->dest_constraints,
1265: id->ndest_constraints);
1.33 markus 1266: }
1.271 djm 1267: /* success */
1.228 markus 1268: id->key = k;
1.157 canacar 1269: id->comment = comment;
1270: id->death = death;
1271: id->confirm = confirm;
1.238 djm 1272: id->sk_provider = sk_provider;
1.281 djm 1273: id->dest_constraints = dest_constraints;
1274: id->ndest_constraints = ndest_constraints;
1.238 djm 1275:
1276: if ((fp = sshkey_fingerprint(k, SSH_FP_HASH_DEFAULT,
1277: SSH_FP_DEFAULT)) == NULL)
1.266 djm 1278: fatal_f("sshkey_fingerprint failed");
1279: debug_f("add %s %s \"%.100s\" (life: %u) (confirm: %u) "
1.281 djm 1280: "(provider: %s) (destination constraints: %zu)",
1281: sshkey_ssh_name(k), fp, comment, seconds, confirm,
1282: sk_provider == NULL ? "none" : sk_provider, ndest_constraints);
1.238 djm 1283: free(fp);
1.271 djm 1284: /* transferred */
1285: k = NULL;
1286: comment = NULL;
1287: sk_provider = NULL;
1.281 djm 1288: dest_constraints = NULL;
1289: ndest_constraints = 0;
1.271 djm 1290: success = 1;
1291: out:
1292: free(sk_provider);
1293: free(comment);
1294: sshkey_free(k);
1.281 djm 1295: free_dest_constraints(dest_constraints, ndest_constraints);
1.194 markus 1296: send_status(e, success);
1.1 deraadt 1297: }
1298:
1.88 markus 1299: /* XXX todo: encrypt sensitive data with passphrase */
1300: static void
1301: process_lock_agent(SocketEntry *e, int lock)
1302: {
1.203 dtucker 1303: int r, success = 0, delay;
1.213 djm 1304: char *passwd;
1305: u_char passwdhash[LOCK_SIZE];
1.203 dtucker 1306: static u_int fail_count = 0;
1307: size_t pwlen;
1308:
1.269 djm 1309: debug2_f("entering");
1.226 djm 1310: /*
1311: * This is deliberately fatal: the user has requested that we lock,
1312: * but we can't parse their request properly. The only safe thing to
1313: * do is abort.
1314: */
1.203 dtucker 1315: if ((r = sshbuf_get_cstring(e->request, &passwd, &pwlen)) != 0)
1.266 djm 1316: fatal_fr(r, "parse");
1.203 dtucker 1317: if (pwlen == 0) {
1318: debug("empty password not supported");
1319: } else if (locked && !lock) {
1320: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1321: passwdhash, sizeof(passwdhash), LOCK_ROUNDS) < 0)
1322: fatal("bcrypt_pbkdf");
1.213 djm 1323: if (timingsafe_bcmp(passwdhash, lock_pwhash, LOCK_SIZE) == 0) {
1.203 dtucker 1324: debug("agent unlocked");
1325: locked = 0;
1326: fail_count = 0;
1.213 djm 1327: explicit_bzero(lock_pwhash, sizeof(lock_pwhash));
1.203 dtucker 1328: success = 1;
1329: } else {
1330: /* delay in 0.1s increments up to 10s */
1331: if (fail_count < 100)
1332: fail_count++;
1333: delay = 100000 * fail_count;
1334: debug("unlock failed, delaying %0.1lf seconds",
1335: (double)delay/1000000);
1336: usleep(delay);
1337: }
1338: explicit_bzero(passwdhash, sizeof(passwdhash));
1.88 markus 1339: } else if (!locked && lock) {
1.203 dtucker 1340: debug("agent locked");
1.88 markus 1341: locked = 1;
1.203 dtucker 1342: arc4random_buf(lock_salt, sizeof(lock_salt));
1343: if (bcrypt_pbkdf(passwd, pwlen, lock_salt, sizeof(lock_salt),
1.213 djm 1344: lock_pwhash, sizeof(lock_pwhash), LOCK_ROUNDS) < 0)
1.203 dtucker 1345: fatal("bcrypt_pbkdf");
1.88 markus 1346: success = 1;
1347: }
1.256 jsg 1348: freezero(passwd, pwlen);
1.194 markus 1349: send_status(e, success);
1.88 markus 1350: }
1351:
1352: static void
1.221 djm 1353: no_identities(SocketEntry *e)
1.88 markus 1354: {
1.194 markus 1355: struct sshbuf *msg;
1356: int r;
1.88 markus 1357:
1.194 markus 1358: if ((msg = sshbuf_new()) == NULL)
1.266 djm 1359: fatal_f("sshbuf_new failed");
1.221 djm 1360: if ((r = sshbuf_put_u8(msg, SSH2_AGENT_IDENTITIES_ANSWER)) != 0 ||
1.194 markus 1361: (r = sshbuf_put_u32(msg, 0)) != 0 ||
1362: (r = sshbuf_put_stringb(e->output, msg)) != 0)
1.266 djm 1363: fatal_fr(r, "compose");
1.194 markus 1364: sshbuf_free(msg);
1.88 markus 1365: }
1.59 markus 1366:
1.163 markus 1367: #ifdef ENABLE_PKCS11
1.59 markus 1368: static void
1.158 djm 1369: process_add_smartcard_key(SocketEntry *e)
1.59 markus 1370: {
1.226 djm 1371: char *provider = NULL, *pin = NULL, canonical_provider[PATH_MAX];
1.253 djm 1372: char **comments = NULL;
1.221 djm 1373: int r, i, count = 0, success = 0, confirm = 0;
1.271 djm 1374: u_int seconds = 0;
1.174 dtucker 1375: time_t death = 0;
1.194 markus 1376: struct sshkey **keys = NULL, *k;
1.84 markus 1377: Identity *id;
1.281 djm 1378: struct dest_constraint *dest_constraints = NULL;
1379: size_t ndest_constraints = 0;
1.75 deraadt 1380:
1.269 djm 1381: debug2_f("entering");
1.194 markus 1382: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
1.226 djm 1383: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) {
1.266 djm 1384: error_fr(r, "parse");
1.226 djm 1385: goto send;
1386: }
1.271 djm 1387: if (parse_key_constraints(e->request, NULL, &death, &seconds, &confirm,
1.281 djm 1388: NULL, &dest_constraints, &ndest_constraints) != 0) {
1.271 djm 1389: error_f("failed to parse constraints");
1390: goto send;
1.110 djm 1391: }
1.215 djm 1392: if (realpath(provider, canonical_provider) == NULL) {
1393: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
1394: provider, strerror(errno));
1395: goto send;
1396: }
1.260 djm 1397: if (match_pattern_list(canonical_provider, allowed_providers, 0) != 1) {
1.215 djm 1398: verbose("refusing PKCS#11 add of \"%.100s\": "
1.260 djm 1399: "provider not allowed", canonical_provider);
1.215 djm 1400: goto send;
1401: }
1.266 djm 1402: debug_f("add %.100s", canonical_provider);
1.110 djm 1403: if (lifetime && !death)
1.175 dtucker 1404: death = monotime() + lifetime;
1.110 djm 1405:
1.253 djm 1406: count = pkcs11_add_provider(canonical_provider, pin, &keys, &comments);
1.163 markus 1407: for (i = 0; i < count; i++) {
1.84 markus 1408: k = keys[i];
1.221 djm 1409: if (lookup_identity(k) == NULL) {
1.163 markus 1410: id = xcalloc(1, sizeof(Identity));
1.84 markus 1411: id->key = k;
1.253 djm 1412: keys[i] = NULL; /* transferred */
1.215 djm 1413: id->provider = xstrdup(canonical_provider);
1.253 djm 1414: if (*comments[i] != '\0') {
1415: id->comment = comments[i];
1416: comments[i] = NULL; /* transferred */
1417: } else {
1418: id->comment = xstrdup(canonical_provider);
1419: }
1.110 djm 1420: id->death = death;
1421: id->confirm = confirm;
1.281 djm 1422: id->dest_constraints = dest_constraints;
1423: id->ndest_constraints = ndest_constraints;
1424: dest_constraints = NULL; /* transferred */
1425: ndest_constraints = 0;
1.221 djm 1426: TAILQ_INSERT_TAIL(&idtab->idlist, id, next);
1427: idtab->nentries++;
1.84 markus 1428: success = 1;
1429: }
1.271 djm 1430: /* XXX update constraints for existing keys */
1.253 djm 1431: sshkey_free(keys[i]);
1432: free(comments[i]);
1.59 markus 1433: }
1434: send:
1.173 djm 1435: free(pin);
1436: free(provider);
1437: free(keys);
1.253 djm 1438: free(comments);
1.281 djm 1439: free_dest_constraints(dest_constraints, ndest_constraints);
1.194 markus 1440: send_status(e, success);
1.59 markus 1441: }
1442:
1443: static void
1444: process_remove_smartcard_key(SocketEntry *e)
1445: {
1.217 djm 1446: char *provider = NULL, *pin = NULL, canonical_provider[PATH_MAX];
1.221 djm 1447: int r, success = 0;
1.163 markus 1448: Identity *id, *nxt;
1.59 markus 1449:
1.269 djm 1450: debug2_f("entering");
1.194 markus 1451: if ((r = sshbuf_get_cstring(e->request, &provider, NULL)) != 0 ||
1.226 djm 1452: (r = sshbuf_get_cstring(e->request, &pin, NULL)) != 0) {
1.266 djm 1453: error_fr(r, "parse");
1.226 djm 1454: goto send;
1455: }
1.173 djm 1456: free(pin);
1.59 markus 1457:
1.217 djm 1458: if (realpath(provider, canonical_provider) == NULL) {
1459: verbose("failed PKCS#11 add of \"%.100s\": realpath: %s",
1460: provider, strerror(errno));
1461: goto send;
1462: }
1463:
1.266 djm 1464: debug_f("remove %.100s", canonical_provider);
1.221 djm 1465: for (id = TAILQ_FIRST(&idtab->idlist); id; id = nxt) {
1466: nxt = TAILQ_NEXT(id, next);
1467: /* Skip file--based keys */
1468: if (id->provider == NULL)
1469: continue;
1470: if (!strcmp(canonical_provider, id->provider)) {
1471: TAILQ_REMOVE(&idtab->idlist, id, next);
1472: free_identity(id);
1473: idtab->nentries--;
1.59 markus 1474: }
1475: }
1.217 djm 1476: if (pkcs11_del_provider(canonical_provider) == 0)
1.163 markus 1477: success = 1;
1478: else
1.266 djm 1479: error_f("pkcs11_del_provider failed");
1.218 deraadt 1480: send:
1.173 djm 1481: free(provider);
1.194 markus 1482: send_status(e, success);
1.59 markus 1483: }
1.163 markus 1484: #endif /* ENABLE_PKCS11 */
1.59 markus 1485:
1.280 djm 1486: static int
1487: process_ext_session_bind(SocketEntry *e)
1488: {
1489: int r, sid_match, key_match;
1490: struct sshkey *key = NULL;
1491: struct sshbuf *sid = NULL, *sig = NULL;
1492: char *fp = NULL;
1493: size_t i;
1.281 djm 1494: u_char fwd = 0;
1.280 djm 1495:
1496: debug2_f("entering");
1497: if ((r = sshkey_froms(e->request, &key)) != 0 ||
1498: (r = sshbuf_froms(e->request, &sid)) != 0 ||
1499: (r = sshbuf_froms(e->request, &sig)) != 0 ||
1500: (r = sshbuf_get_u8(e->request, &fwd)) != 0) {
1501: error_fr(r, "parse");
1502: goto out;
1503: }
1504: if ((fp = sshkey_fingerprint(key, SSH_FP_HASH_DEFAULT,
1505: SSH_FP_DEFAULT)) == NULL)
1506: fatal_f("fingerprint failed");
1507: /* check signature with hostkey on session ID */
1508: if ((r = sshkey_verify(key, sshbuf_ptr(sig), sshbuf_len(sig),
1509: sshbuf_ptr(sid), sshbuf_len(sid), NULL, 0, NULL)) != 0) {
1510: error_fr(r, "sshkey_verify for %s %s", sshkey_type(key), fp);
1511: goto out;
1512: }
1513: /* check whether sid/key already recorded */
1514: for (i = 0; i < e->nsession_ids; i++) {
1.281 djm 1515: if (!e->session_ids[i].forwarded) {
1516: error_f("attempt to bind session ID to socket "
1517: "previously bound for authentication attempt");
1518: r = -1;
1519: goto out;
1520: }
1.280 djm 1521: sid_match = buf_equal(sid, e->session_ids[i].sid) == 0;
1522: key_match = sshkey_equal(key, e->session_ids[i].key);
1523: if (sid_match && key_match) {
1524: debug_f("session ID already recorded for %s %s",
1525: sshkey_type(key), fp);
1526: r = 0;
1527: goto out;
1528: } else if (sid_match) {
1529: error_f("session ID recorded against different key "
1530: "for %s %s", sshkey_type(key), fp);
1531: r = -1;
1532: goto out;
1533: }
1534: /*
1535: * new sid with previously-seen key can happen, e.g. multiple
1536: * connections to the same host.
1537: */
1538: }
1539: /* record new key/sid */
1540: if (e->nsession_ids >= AGENT_MAX_SESSION_IDS) {
1541: error_f("too many session IDs recorded");
1542: goto out;
1543: }
1544: e->session_ids = xrecallocarray(e->session_ids, e->nsession_ids,
1545: e->nsession_ids + 1, sizeof(*e->session_ids));
1546: i = e->nsession_ids++;
1547: debug_f("recorded %s %s (slot %zu of %d)", sshkey_type(key), fp, i,
1548: AGENT_MAX_SESSION_IDS);
1549: e->session_ids[i].key = key;
1550: e->session_ids[i].forwarded = fwd != 0;
1551: key = NULL; /* transferred */
1552: /* can't transfer sid; it's refcounted and scoped to request's life */
1553: if ((e->session_ids[i].sid = sshbuf_new()) == NULL)
1554: fatal_f("sshbuf_new");
1555: if ((r = sshbuf_putb(e->session_ids[i].sid, sid)) != 0)
1556: fatal_fr(r, "sshbuf_putb session ID");
1557: /* success */
1558: r = 0;
1559: out:
1.288 ! djm 1560: free(fp);
1.280 djm 1561: sshkey_free(key);
1562: sshbuf_free(sid);
1563: sshbuf_free(sig);
1564: return r == 0 ? 1 : 0;
1565: }
1566:
1567: static void
1568: process_extension(SocketEntry *e)
1569: {
1570: int r, success = 0;
1571: char *name;
1572:
1573: debug2_f("entering");
1574: if ((r = sshbuf_get_cstring(e->request, &name, NULL)) != 0) {
1575: error_fr(r, "parse");
1576: goto send;
1577: }
1578: if (strcmp(name, "session-bind@openssh.com") == 0)
1579: success = process_ext_session_bind(e);
1580: else
1581: debug_f("unsupported extension \"%s\"", name);
1.285 djm 1582: free(name);
1.280 djm 1583: send:
1584: send_status(e, success);
1585: }
1.264 djm 1586: /*
1587: * dispatch incoming message.
1588: * returns 1 on success, 0 for incomplete messages or -1 on error.
1589: */
1.223 djm 1590: static int
1591: process_message(u_int socknum)
1.1 deraadt 1592: {
1.194 markus 1593: u_int msg_len;
1594: u_char type;
1595: const u_char *cp;
1596: int r;
1.223 djm 1597: SocketEntry *e;
1598:
1.266 djm 1599: if (socknum >= sockets_alloc)
1600: fatal_f("sock %u >= allocated %u", socknum, sockets_alloc);
1.223 djm 1601: e = &sockets[socknum];
1.89 markus 1602:
1.194 markus 1603: if (sshbuf_len(e->input) < 5)
1.223 djm 1604: return 0; /* Incomplete message header. */
1.194 markus 1605: cp = sshbuf_ptr(e->input);
1606: msg_len = PEEK_U32(cp);
1.223 djm 1607: if (msg_len > AGENT_MAX_LEN) {
1.266 djm 1608: debug_f("socket %u (fd=%d) message too long %u > %u",
1609: socknum, e->fd, msg_len, AGENT_MAX_LEN);
1.223 djm 1610: return -1;
1.21 markus 1611: }
1.194 markus 1612: if (sshbuf_len(e->input) < msg_len + 4)
1.223 djm 1613: return 0; /* Incomplete message body. */
1.87 markus 1614:
1615: /* move the current input to e->request */
1.194 markus 1616: sshbuf_reset(e->request);
1617: if ((r = sshbuf_get_stringb(e->input, e->request)) != 0 ||
1.223 djm 1618: (r = sshbuf_get_u8(e->request, &type)) != 0) {
1619: if (r == SSH_ERR_MESSAGE_INCOMPLETE ||
1620: r == SSH_ERR_STRING_TOO_LARGE) {
1.266 djm 1621: error_fr(r, "parse");
1.223 djm 1622: return -1;
1623: }
1.266 djm 1624: fatal_fr(r, "parse");
1.223 djm 1625: }
1626:
1.266 djm 1627: debug_f("socket %u (fd=%d) type %d", socknum, e->fd, type);
1.21 markus 1628:
1.230 djm 1629: /* check whether agent is locked */
1.88 markus 1630: if (locked && type != SSH_AGENTC_UNLOCK) {
1.194 markus 1631: sshbuf_reset(e->request);
1.88 markus 1632: switch (type) {
1633: case SSH2_AGENTC_REQUEST_IDENTITIES:
1634: /* send empty lists */
1.221 djm 1635: no_identities(e);
1.88 markus 1636: break;
1637: default:
1638: /* send a fail message for all other request types */
1.194 markus 1639: send_status(e, 0);
1.88 markus 1640: }
1.264 djm 1641: return 1;
1.88 markus 1642: }
1643:
1.21 markus 1644: switch (type) {
1.88 markus 1645: case SSH_AGENTC_LOCK:
1646: case SSH_AGENTC_UNLOCK:
1647: process_lock_agent(e, type == SSH_AGENTC_LOCK);
1648: break;
1.21 markus 1649: case SSH_AGENTC_REMOVE_ALL_RSA_IDENTITIES:
1.221 djm 1650: process_remove_all_identities(e); /* safe for !WITH_SSH1 */
1.33 markus 1651: break;
1652: /* ssh2 */
1653: case SSH2_AGENTC_SIGN_REQUEST:
1654: process_sign_request2(e);
1655: break;
1656: case SSH2_AGENTC_REQUEST_IDENTITIES:
1.221 djm 1657: process_request_identities(e);
1.33 markus 1658: break;
1659: case SSH2_AGENTC_ADD_IDENTITY:
1.94 markus 1660: case SSH2_AGENTC_ADD_ID_CONSTRAINED:
1.221 djm 1661: process_add_identity(e);
1.33 markus 1662: break;
1663: case SSH2_AGENTC_REMOVE_IDENTITY:
1.221 djm 1664: process_remove_identity(e);
1.33 markus 1665: break;
1666: case SSH2_AGENTC_REMOVE_ALL_IDENTITIES:
1.221 djm 1667: process_remove_all_identities(e);
1.21 markus 1668: break;
1.163 markus 1669: #ifdef ENABLE_PKCS11
1.59 markus 1670: case SSH_AGENTC_ADD_SMARTCARD_KEY:
1.110 djm 1671: case SSH_AGENTC_ADD_SMARTCARD_KEY_CONSTRAINED:
1.59 markus 1672: process_add_smartcard_key(e);
1.75 deraadt 1673: break;
1.59 markus 1674: case SSH_AGENTC_REMOVE_SMARTCARD_KEY:
1675: process_remove_smartcard_key(e);
1.75 deraadt 1676: break;
1.163 markus 1677: #endif /* ENABLE_PKCS11 */
1.280 djm 1678: case SSH_AGENTC_EXTENSION:
1679: process_extension(e);
1680: break;
1.21 markus 1681: default:
1682: /* Unknown message. Respond with failure. */
1683: error("Unknown message %d", type);
1.194 markus 1684: sshbuf_reset(e->request);
1685: send_status(e, 0);
1.21 markus 1686: break;
1687: }
1.264 djm 1688: return 1;
1.1 deraadt 1689: }
1690:
1.55 itojun 1691: static void
1.73 stevesk 1692: new_socket(sock_type type, int fd)
1.1 deraadt 1693: {
1.112 markus 1694: u_int i, old_alloc, new_alloc;
1.96 deraadt 1695:
1.269 djm 1696: debug_f("type = %s", type == AUTH_CONNECTION ? "CONNECTION" :
1697: (type == AUTH_SOCKET ? "SOCKET" : "UNKNOWN"));
1.119 djm 1698: set_nonblock(fd);
1.21 markus 1699:
1700: if (fd > max_fd)
1701: max_fd = fd;
1702:
1703: for (i = 0; i < sockets_alloc; i++)
1704: if (sockets[i].type == AUTH_UNUSED) {
1705: sockets[i].fd = fd;
1.266 djm 1706: if ((sockets[i].input = sshbuf_new()) == NULL ||
1707: (sockets[i].output = sshbuf_new()) == NULL ||
1708: (sockets[i].request = sshbuf_new()) == NULL)
1709: fatal_f("sshbuf_new failed");
1.112 markus 1710: sockets[i].type = type;
1.21 markus 1711: return;
1712: }
1713: old_alloc = sockets_alloc;
1.112 markus 1714: new_alloc = sockets_alloc + 10;
1.269 djm 1715: sockets = xrecallocarray(sockets, old_alloc, new_alloc,
1716: sizeof(sockets[0]));
1.112 markus 1717: for (i = old_alloc; i < new_alloc; i++)
1.21 markus 1718: sockets[i].type = AUTH_UNUSED;
1.112 markus 1719: sockets_alloc = new_alloc;
1.21 markus 1720: sockets[old_alloc].fd = fd;
1.266 djm 1721: if ((sockets[old_alloc].input = sshbuf_new()) == NULL ||
1722: (sockets[old_alloc].output = sshbuf_new()) == NULL ||
1723: (sockets[old_alloc].request = sshbuf_new()) == NULL)
1724: fatal_f("sshbuf_new failed");
1.112 markus 1725: sockets[old_alloc].type = type;
1.1 deraadt 1726: }
1727:
1.55 itojun 1728: static int
1.223 djm 1729: handle_socket_read(u_int socknum)
1.1 deraadt 1730: {
1.223 djm 1731: struct sockaddr_un sunaddr;
1732: socklen_t slen;
1733: uid_t euid;
1734: gid_t egid;
1735: int fd;
1736:
1737: slen = sizeof(sunaddr);
1738: fd = accept(sockets[socknum].fd, (struct sockaddr *)&sunaddr, &slen);
1.237 deraadt 1739: if (fd == -1) {
1.223 djm 1740: error("accept from AUTH_SOCKET: %s", strerror(errno));
1741: return -1;
1742: }
1.237 deraadt 1743: if (getpeereid(fd, &euid, &egid) == -1) {
1.223 djm 1744: error("getpeereid %d failed: %s", fd, strerror(errno));
1745: close(fd);
1746: return -1;
1747: }
1748: if ((euid != 0) && (getuid() != euid)) {
1749: error("uid mismatch: peer euid %u != uid %u",
1750: (u_int) euid, (u_int) getuid());
1751: close(fd);
1752: return -1;
1753: }
1754: new_socket(AUTH_CONNECTION, fd);
1755: return 0;
1756: }
1757:
1758: static int
1759: handle_conn_read(u_int socknum)
1760: {
1.233 djm 1761: char buf[AGENT_RBUF_LEN];
1.223 djm 1762: ssize_t len;
1763: int r;
1764:
1765: if ((len = read(sockets[socknum].fd, buf, sizeof(buf))) <= 0) {
1766: if (len == -1) {
1767: if (errno == EAGAIN || errno == EINTR)
1768: return 0;
1.266 djm 1769: error_f("read error on socket %u (fd %d): %s",
1770: socknum, sockets[socknum].fd, strerror(errno));
1.223 djm 1771: }
1772: return -1;
1773: }
1774: if ((r = sshbuf_put(sockets[socknum].input, buf, len)) != 0)
1.266 djm 1775: fatal_fr(r, "compose");
1.223 djm 1776: explicit_bzero(buf, sizeof(buf));
1.264 djm 1777: for (;;) {
1778: if ((r = process_message(socknum)) == -1)
1779: return -1;
1780: else if (r == 0)
1781: break;
1782: }
1.223 djm 1783: return 0;
1784: }
1785:
1786: static int
1787: handle_conn_write(u_int socknum)
1788: {
1789: ssize_t len;
1790: int r;
1791:
1792: if (sshbuf_len(sockets[socknum].output) == 0)
1793: return 0; /* shouldn't happen */
1794: if ((len = write(sockets[socknum].fd,
1795: sshbuf_ptr(sockets[socknum].output),
1796: sshbuf_len(sockets[socknum].output))) <= 0) {
1797: if (len == -1) {
1798: if (errno == EAGAIN || errno == EINTR)
1799: return 0;
1.266 djm 1800: error_f("read error on socket %u (fd %d): %s",
1801: socknum, sockets[socknum].fd, strerror(errno));
1.223 djm 1802: }
1803: return -1;
1804: }
1805: if ((r = sshbuf_consume(sockets[socknum].output, len)) != 0)
1.266 djm 1806: fatal_fr(r, "consume");
1.223 djm 1807: return 0;
1808: }
1809:
1810: static void
1.231 djm 1811: after_poll(struct pollfd *pfd, size_t npfd, u_int maxfds)
1.223 djm 1812: {
1813: size_t i;
1.231 djm 1814: u_int socknum, activefds = npfd;
1.223 djm 1815:
1816: for (i = 0; i < npfd; i++) {
1817: if (pfd[i].revents == 0)
1818: continue;
1819: /* Find sockets entry */
1820: for (socknum = 0; socknum < sockets_alloc; socknum++) {
1821: if (sockets[socknum].type != AUTH_SOCKET &&
1822: sockets[socknum].type != AUTH_CONNECTION)
1823: continue;
1824: if (pfd[i].fd == sockets[socknum].fd)
1825: break;
1826: }
1827: if (socknum >= sockets_alloc) {
1.266 djm 1828: error_f("no socket for fd %d", pfd[i].fd);
1.223 djm 1829: continue;
1830: }
1831: /* Process events */
1832: switch (sockets[socknum].type) {
1833: case AUTH_SOCKET:
1.231 djm 1834: if ((pfd[i].revents & (POLLIN|POLLERR)) == 0)
1835: break;
1836: if (npfd > maxfds) {
1837: debug3("out of fds (active %u >= limit %u); "
1838: "skipping accept", activefds, maxfds);
1839: break;
1840: }
1841: if (handle_socket_read(socknum) == 0)
1842: activefds++;
1.223 djm 1843: break;
1844: case AUTH_CONNECTION:
1.279 djm 1845: if ((pfd[i].revents & (POLLIN|POLLHUP|POLLERR)) != 0 &&
1846: handle_conn_read(socknum) != 0)
1.231 djm 1847: goto close_sock;
1848: if ((pfd[i].revents & (POLLOUT|POLLHUP)) != 0 &&
1849: handle_conn_write(socknum) != 0) {
1850: close_sock:
1851: if (activefds == 0)
1852: fatal("activefds == 0 at close_sock");
1.223 djm 1853: close_socket(&sockets[socknum]);
1.231 djm 1854: activefds--;
1.223 djm 1855: break;
1856: }
1857: break;
1858: default:
1859: break;
1860: }
1861: }
1862: }
1863:
1864: static int
1.231 djm 1865: prepare_poll(struct pollfd **pfdp, size_t *npfdp, int *timeoutp, u_int maxfds)
1.223 djm 1866: {
1867: struct pollfd *pfd = *pfdp;
1868: size_t i, j, npfd = 0;
1.174 dtucker 1869: time_t deadline;
1.233 djm 1870: int r;
1.46 markus 1871:
1.223 djm 1872: /* Count active sockets */
1.46 markus 1873: for (i = 0; i < sockets_alloc; i++) {
1.21 markus 1874: switch (sockets[i].type) {
1875: case AUTH_SOCKET:
1876: case AUTH_CONNECTION:
1.223 djm 1877: npfd++;
1.21 markus 1878: break;
1879: case AUTH_UNUSED:
1880: break;
1881: default:
1882: fatal("Unknown socket type %d", sockets[i].type);
1883: break;
1884: }
1.46 markus 1885: }
1.223 djm 1886: if (npfd != *npfdp &&
1887: (pfd = recallocarray(pfd, *npfdp, npfd, sizeof(*pfd))) == NULL)
1.266 djm 1888: fatal_f("recallocarray failed");
1.223 djm 1889: *pfdp = pfd;
1890: *npfdp = npfd;
1.46 markus 1891:
1.223 djm 1892: for (i = j = 0; i < sockets_alloc; i++) {
1.46 markus 1893: switch (sockets[i].type) {
1894: case AUTH_SOCKET:
1.231 djm 1895: if (npfd > maxfds) {
1896: debug3("out of fds (active %zu >= limit %u); "
1897: "skipping arming listener", npfd, maxfds);
1898: break;
1899: }
1900: pfd[j].fd = sockets[i].fd;
1901: pfd[j].revents = 0;
1902: pfd[j].events = POLLIN;
1903: j++;
1904: break;
1.46 markus 1905: case AUTH_CONNECTION:
1.223 djm 1906: pfd[j].fd = sockets[i].fd;
1907: pfd[j].revents = 0;
1.233 djm 1908: /*
1909: * Only prepare to read if we can handle a full-size
1910: * input read buffer and enqueue a max size reply..
1911: */
1912: if ((r = sshbuf_check_reserve(sockets[i].input,
1913: AGENT_RBUF_LEN)) == 0 &&
1914: (r = sshbuf_check_reserve(sockets[i].output,
1.278 djm 1915: AGENT_MAX_LEN)) == 0)
1.233 djm 1916: pfd[j].events = POLLIN;
1.266 djm 1917: else if (r != SSH_ERR_NO_BUFFER_SPACE)
1918: fatal_fr(r, "reserve");
1.194 markus 1919: if (sshbuf_len(sockets[i].output) > 0)
1.223 djm 1920: pfd[j].events |= POLLOUT;
1921: j++;
1.46 markus 1922: break;
1923: default:
1924: break;
1925: }
1926: }
1.155 dtucker 1927: deadline = reaper();
1928: if (parent_alive_interval != 0)
1929: deadline = (deadline == 0) ? parent_alive_interval :
1.214 deraadt 1930: MINIMUM(deadline, parent_alive_interval);
1.155 dtucker 1931: if (deadline == 0) {
1.224 djm 1932: *timeoutp = -1; /* INFTIM */
1.155 dtucker 1933: } else {
1.223 djm 1934: if (deadline > INT_MAX / 1000)
1935: *timeoutp = INT_MAX / 1000;
1936: else
1937: *timeoutp = deadline * 1000;
1.155 dtucker 1938: }
1.46 markus 1939: return (1);
1.21 markus 1940: }
1941:
1.55 itojun 1942: static void
1.113 markus 1943: cleanup_socket(void)
1.15 markus 1944: {
1.187 djm 1945: if (cleanup_pid != 0 && getpid() != cleanup_pid)
1946: return;
1.266 djm 1947: debug_f("cleanup");
1.48 deraadt 1948: if (socket_name[0])
1949: unlink(socket_name);
1950: if (socket_dir[0])
1951: rmdir(socket_dir);
1.10 markus 1952: }
1953:
1.114 markus 1954: void
1.15 markus 1955: cleanup_exit(int i)
1956: {
1.113 markus 1957: cleanup_socket();
1958: _exit(i);
1.15 markus 1959: }
1960:
1.135 deraadt 1961: /*ARGSUSED*/
1.55 itojun 1962: static void
1.48 deraadt 1963: cleanup_handler(int sig)
1964: {
1.113 markus 1965: cleanup_socket();
1.163 markus 1966: #ifdef ENABLE_PKCS11
1967: pkcs11_terminate();
1968: #endif
1.48 deraadt 1969: _exit(2);
1.113 markus 1970: }
1971:
1.68 markus 1972: static void
1.155 dtucker 1973: check_parent_exists(void)
1.68 markus 1974: {
1.172 dtucker 1975: /*
1976: * If our parent has exited then getppid() will return (pid_t)1,
1977: * so testing for that should be safe.
1978: */
1979: if (parent_pid != -1 && getppid() != parent_pid) {
1.68 markus 1980: /* printf("Parent has died - Authentication agent exiting.\n"); */
1.155 dtucker 1981: cleanup_socket();
1982: _exit(2);
1.68 markus 1983: }
1.48 deraadt 1984: }
1985:
1.55 itojun 1986: static void
1.50 itojun 1987: usage(void)
1.15 markus 1988: {
1.184 deraadt 1989: fprintf(stderr,
1.250 jmc 1990: "usage: ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash]\n"
1.261 jmc 1991: " [-P allowed_providers] [-t life]\n"
1.260 djm 1992: " ssh-agent [-a bind_address] [-E fingerprint_hash] [-P allowed_providers]\n"
1.259 dtucker 1993: " [-t life] command [arg ...]\n"
1.250 jmc 1994: " ssh-agent [-c | -s] -k\n");
1.21 markus 1995: exit(1);
1.15 markus 1996: }
1997:
1.2 provos 1998: int
1999: main(int ac, char **av)
1.1 deraadt 2000: {
1.201 djm 2001: int c_flag = 0, d_flag = 0, D_flag = 0, k_flag = 0, s_flag = 0;
1.265 djm 2002: int sock, ch, result, saved_errno;
1.96 deraadt 2003: char *shell, *format, *pidstr, *agentsocket = NULL;
1.41 markus 2004: struct rlimit rlim;
1.96 deraadt 2005: extern int optind;
1.98 stevesk 2006: extern char *optarg;
1.21 markus 2007: pid_t pid;
1.96 deraadt 2008: char pidstrbuf[1 + 3 * sizeof pid];
1.161 tobias 2009: size_t len;
1.189 djm 2010: mode_t prev_mask;
1.224 djm 2011: int timeout = -1; /* INFTIM */
1.223 djm 2012: struct pollfd *pfd = NULL;
2013: size_t npfd = 0;
1.231 djm 2014: u_int maxfds;
1.123 djm 2015:
2016: /* Ensure that fds 0, 1 and 2 are open or directed to /dev/null */
2017: sanitise_stdfd();
1.99 markus 2018:
2019: /* drop */
2020: setegid(getgid());
2021: setgid(getgid());
1.53 markus 2022:
1.231 djm 2023: if (getrlimit(RLIMIT_NOFILE, &rlim) == -1)
2024: fatal("%s: getrlimit: %s", __progname, strerror(errno));
2025:
1.185 markus 2026: #ifdef WITH_OPENSSL
1.170 djm 2027: OpenSSL_add_all_algorithms();
1.185 markus 2028: #endif
1.21 markus 2029:
1.258 djm 2030: while ((ch = getopt(ac, av, "cDdksE:a:O:P:t:")) != -1) {
1.21 markus 2031: switch (ch) {
1.192 djm 2032: case 'E':
2033: fingerprint_hash = ssh_digest_alg_by_name(optarg);
2034: if (fingerprint_hash == -1)
2035: fatal("Invalid hash algorithm \"%s\"", optarg);
2036: break;
1.21 markus 2037: case 'c':
2038: if (s_flag)
2039: usage();
2040: c_flag++;
2041: break;
2042: case 'k':
2043: k_flag++;
1.258 djm 2044: break;
2045: case 'O':
2046: if (strcmp(optarg, "no-restrict-websafe") == 0)
2047: restrict_websafe = 0;
2048: else
2049: fatal("Unknown -O option");
1.21 markus 2050: break;
1.215 djm 2051: case 'P':
1.260 djm 2052: if (allowed_providers != NULL)
1.215 djm 2053: fatal("-P option already specified");
1.260 djm 2054: allowed_providers = xstrdup(optarg);
1.215 djm 2055: break;
1.21 markus 2056: case 's':
2057: if (c_flag)
2058: usage();
2059: s_flag++;
2060: break;
1.57 markus 2061: case 'd':
1.201 djm 2062: if (d_flag || D_flag)
1.57 markus 2063: usage();
2064: d_flag++;
2065: break;
1.201 djm 2066: case 'D':
2067: if (d_flag || D_flag)
2068: usage();
2069: D_flag++;
2070: break;
1.86 markus 2071: case 'a':
2072: agentsocket = optarg;
1.106 marc 2073: break;
2074: case 't':
2075: if ((lifetime = convtime(optarg)) == -1) {
2076: fprintf(stderr, "Invalid lifetime\n");
2077: usage();
2078: }
1.86 markus 2079: break;
1.21 markus 2080: default:
2081: usage();
2082: }
2083: }
2084: ac -= optind;
2085: av += optind;
2086:
1.201 djm 2087: if (ac > 0 && (c_flag || k_flag || s_flag || d_flag || D_flag))
1.21 markus 2088: usage();
2089:
1.260 djm 2090: if (allowed_providers == NULL)
1.262 djm 2091: allowed_providers = xstrdup(DEFAULT_ALLOWED_PROVIDERS);
1.215 djm 2092:
1.85 markus 2093: if (ac == 0 && !c_flag && !s_flag) {
1.21 markus 2094: shell = getenv("SHELL");
1.161 tobias 2095: if (shell != NULL && (len = strlen(shell)) > 2 &&
2096: strncmp(shell + len - 3, "csh", 3) == 0)
1.21 markus 2097: c_flag = 1;
2098: }
2099: if (k_flag) {
1.136 deraadt 2100: const char *errstr = NULL;
2101:
1.21 markus 2102: pidstr = getenv(SSH_AGENTPID_ENV_NAME);
2103: if (pidstr == NULL) {
2104: fprintf(stderr, "%s not set, cannot kill agent\n",
1.46 markus 2105: SSH_AGENTPID_ENV_NAME);
1.21 markus 2106: exit(1);
2107: }
1.136 deraadt 2108: pid = (int)strtonum(pidstr, 2, INT_MAX, &errstr);
2109: if (errstr) {
2110: fprintf(stderr,
2111: "%s=\"%s\", which is not a good PID: %s\n",
2112: SSH_AGENTPID_ENV_NAME, pidstr, errstr);
1.21 markus 2113: exit(1);
2114: }
2115: if (kill(pid, SIGTERM) == -1) {
2116: perror("kill");
2117: exit(1);
2118: }
2119: format = c_flag ? "unsetenv %s;\n" : "unset %s;\n";
1.140 djm 2120: printf(format, SSH_AUTHSOCKET_ENV_NAME);
2121: printf(format, SSH_AGENTPID_ENV_NAME);
1.91 mpech 2122: printf("echo Agent pid %ld killed;\n", (long)pid);
1.21 markus 2123: exit(0);
2124: }
1.231 djm 2125:
2126: /*
2127: * Minimum file descriptors:
2128: * stdio (3) + listener (1) + syslog (1 maybe) + connection (1) +
2129: * a few spare for libc / stack protectors / sanitisers, etc.
2130: */
2131: #define SSH_AGENT_MIN_FDS (3+1+1+1+4)
2132: if (rlim.rlim_cur < SSH_AGENT_MIN_FDS)
1.232 djm 2133: fatal("%s: file descriptor rlimit %lld too low (minimum %u)",
1.231 djm 2134: __progname, (long long)rlim.rlim_cur, SSH_AGENT_MIN_FDS);
2135: maxfds = rlim.rlim_cur - SSH_AGENT_MIN_FDS;
2136:
1.21 markus 2137: parent_pid = getpid();
2138:
1.86 markus 2139: if (agentsocket == NULL) {
2140: /* Create private directory for agent socket */
1.171 djm 2141: mktemp_proto(socket_dir, sizeof(socket_dir));
1.86 markus 2142: if (mkdtemp(socket_dir) == NULL) {
2143: perror("mkdtemp: private socket dir");
2144: exit(1);
2145: }
1.91 mpech 2146: snprintf(socket_name, sizeof socket_name, "%s/agent.%ld", socket_dir,
2147: (long)parent_pid);
1.86 markus 2148: } else {
2149: /* Try to use specified agent socket */
2150: socket_dir[0] = '\0';
2151: strlcpy(socket_name, agentsocket, sizeof socket_name);
1.21 markus 2152: }
2153:
1.23 markus 2154: /*
2155: * Create socket early so it will exist before command gets run from
2156: * the parent.
2157: */
1.189 djm 2158: prev_mask = umask(0177);
1.188 millert 2159: sock = unix_listener(socket_name, SSH_LISTEN_BACKLOG, 0);
1.21 markus 2160: if (sock < 0) {
1.188 millert 2161: /* XXX - unix_listener() calls error() not perror() */
1.121 djm 2162: *socket_name = '\0'; /* Don't unlink any existing file */
1.21 markus 2163: cleanup_exit(1);
2164: }
1.189 djm 2165: umask(prev_mask);
1.46 markus 2166:
1.23 markus 2167: /*
2168: * Fork, and have the parent execute the command, if any, or present
2169: * the socket data. The child continues as the authentication agent.
2170: */
1.201 djm 2171: if (D_flag || d_flag) {
2172: log_init(__progname,
2173: d_flag ? SYSLOG_LEVEL_DEBUG3 : SYSLOG_LEVEL_INFO,
2174: SYSLOG_FACILITY_AUTH, 1);
1.57 markus 2175: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
2176: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
2177: SSH_AUTHSOCKET_ENV_NAME);
1.91 mpech 2178: printf("echo Agent pid %ld;\n", (long)parent_pid);
1.210 dtucker 2179: fflush(stdout);
1.57 markus 2180: goto skip;
2181: }
1.21 markus 2182: pid = fork();
2183: if (pid == -1) {
2184: perror("fork");
1.81 stevesk 2185: cleanup_exit(1);
1.21 markus 2186: }
2187: if (pid != 0) { /* Parent - execute the given command. */
2188: close(sock);
1.91 mpech 2189: snprintf(pidstrbuf, sizeof pidstrbuf, "%ld", (long)pid);
1.21 markus 2190: if (ac == 0) {
2191: format = c_flag ? "setenv %s %s;\n" : "%s=%s; export %s;\n";
2192: printf(format, SSH_AUTHSOCKET_ENV_NAME, socket_name,
1.46 markus 2193: SSH_AUTHSOCKET_ENV_NAME);
1.21 markus 2194: printf(format, SSH_AGENTPID_ENV_NAME, pidstrbuf,
1.46 markus 2195: SSH_AGENTPID_ENV_NAME);
1.91 mpech 2196: printf("echo Agent pid %ld;\n", (long)pid);
1.21 markus 2197: exit(0);
2198: }
1.36 deraadt 2199: if (setenv(SSH_AUTHSOCKET_ENV_NAME, socket_name, 1) == -1 ||
2200: setenv(SSH_AGENTPID_ENV_NAME, pidstrbuf, 1) == -1) {
2201: perror("setenv");
2202: exit(1);
2203: }
1.21 markus 2204: execvp(av[0], av);
2205: perror(av[0]);
2206: exit(1);
2207: }
1.81 stevesk 2208: /* child */
2209: log_init(__progname, SYSLOG_LEVEL_INFO, SYSLOG_FACILITY_AUTH, 0);
1.67 stevesk 2210:
2211: if (setsid() == -1) {
1.81 stevesk 2212: error("setsid: %s", strerror(errno));
1.67 stevesk 2213: cleanup_exit(1);
2214: }
2215:
2216: (void)chdir("/");
1.265 djm 2217: if (stdfd_devnull(1, 1, 1) == -1)
1.266 djm 2218: error_f("stdfd_devnull failed");
1.21 markus 2219:
1.41 markus 2220: /* deny core dumps, since memory contains unencrypted private keys */
2221: rlim.rlim_cur = rlim.rlim_max = 0;
1.237 deraadt 2222: if (setrlimit(RLIMIT_CORE, &rlim) == -1) {
1.81 stevesk 2223: error("setrlimit RLIMIT_CORE: %s", strerror(errno));
1.21 markus 2224: cleanup_exit(1);
2225: }
1.57 markus 2226:
2227: skip:
1.187 djm 2228:
2229: cleanup_pid = getpid();
1.163 markus 2230:
2231: #ifdef ENABLE_PKCS11
2232: pkcs11_init(0);
2233: #endif
1.21 markus 2234: new_socket(AUTH_SOCKET, sock);
1.155 dtucker 2235: if (ac > 0)
2236: parent_alive_interval = 10;
1.33 markus 2237: idtab_init();
1.252 dtucker 2238: ssh_signal(SIGPIPE, SIG_IGN);
2239: ssh_signal(SIGINT, (d_flag | D_flag) ? cleanup_handler : SIG_IGN);
2240: ssh_signal(SIGHUP, cleanup_handler);
2241: ssh_signal(SIGTERM, cleanup_handler);
1.205 djm 2242:
1.215 djm 2243: if (pledge("stdio rpath cpath unix id proc exec", NULL) == -1)
1.205 djm 2244: fatal("%s: pledge: %s", __progname, strerror(errno));
1.66 markus 2245:
1.21 markus 2246: while (1) {
1.231 djm 2247: prepare_poll(&pfd, &npfd, &timeout, maxfds);
1.223 djm 2248: result = poll(pfd, npfd, timeout);
1.154 dtucker 2249: saved_errno = errno;
1.155 dtucker 2250: if (parent_alive_interval != 0)
2251: check_parent_exists();
2252: (void) reaper(); /* remove expired keys */
1.237 deraadt 2253: if (result == -1) {
1.154 dtucker 2254: if (saved_errno == EINTR)
1.21 markus 2255: continue;
1.223 djm 2256: fatal("poll: %s", strerror(saved_errno));
1.154 dtucker 2257: } else if (result > 0)
1.231 djm 2258: after_poll(pfd, npfd, maxfds);
1.15 markus 2259: }
1.21 markus 2260: /* NOTREACHED */
1.1 deraadt 2261: }
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