1 /* $OpenBSD: sshconnect2.c,v 1.372 2024/01/08 00:34:34 djm Exp $ */
3 * Copyright (c) 2000 Markus Friedl. All rights reserved.
4 * Copyright (c) 2008 Damien Miller. All rights reserved.
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 #include <sys/types.h>
30 #include <sys/socket.h>
44 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS)
48 #include "openbsd-compat/sys-queue.h"
59 #include "sshconnect.h"
70 #include "pathnames.h"
83 extern char *client_version_string;
84 extern char *server_version_string;
85 extern Options options;
91 static char *xxx_host;
92 static struct sockaddr *xxx_hostaddr;
93 static const struct ssh_conn_info *xxx_conn_info;
96 verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
100 if ((r = sshkey_check_rsa_length(hostkey,
101 options.required_rsa_size)) != 0)
102 fatal_r(r, "Bad server host key");
103 if (verify_host_key(xxx_host, xxx_hostaddr, hostkey,
104 xxx_conn_info) == -1)
105 fatal("Host key verification failed.");
109 /* Returns the first item from a comma-separated algorithm list */
111 first_alg(const char *algs)
116 if ((cp = strchr(ret, ',')) != NULL)
122 order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port,
123 const struct ssh_conn_info *cinfo)
125 char *oavail = NULL, *avail = NULL, *first = NULL, *last = NULL;
126 char *alg = NULL, *hostname = NULL, *ret = NULL, *best = NULL;
128 struct hostkeys *hostkeys = NULL;
132 /* Find all hostkeys for this hostname */
133 get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
134 hostkeys = init_hostkeys();
135 for (i = 0; i < options.num_user_hostfiles; i++)
136 load_hostkeys(hostkeys, hostname, options.user_hostfiles[i], 0);
137 for (i = 0; i < options.num_system_hostfiles; i++) {
138 load_hostkeys(hostkeys, hostname,
139 options.system_hostfiles[i], 0);
141 if (options.known_hosts_command != NULL) {
142 load_hostkeys_command(hostkeys, options.known_hosts_command,
143 "ORDER", cinfo, NULL, hostname);
146 * If a plain public key exists that matches the type of the best
147 * preference HostkeyAlgorithms, then use the whole list as is.
148 * Note that we ignore whether the best preference algorithm is a
149 * certificate type, as sshconnect.c will downgrade certs to
150 * plain keys if necessary.
152 best = first_alg(options.hostkeyalgorithms);
153 if (lookup_key_in_hostkeys_by_type(hostkeys,
154 sshkey_type_plain(sshkey_type_from_name(best)),
155 sshkey_ecdsa_nid_from_name(best), NULL)) {
156 debug3_f("have matching best-preference key type %s, "
157 "using HostkeyAlgorithms verbatim", best);
158 ret = xstrdup(options.hostkeyalgorithms);
163 * Otherwise, prefer the host key algorithms that match known keys
164 * while keeping the ordering of HostkeyAlgorithms as much as possible.
166 oavail = avail = xstrdup(options.hostkeyalgorithms);
167 maxlen = strlen(avail) + 1;
168 first = xmalloc(maxlen);
169 last = xmalloc(maxlen);
170 *first = *last = '\0';
172 #define ALG_APPEND(to, from) \
175 strlcat(to, ",", maxlen); \
176 strlcat(to, from, maxlen); \
179 while ((alg = strsep(&avail, ",")) && *alg != '\0') {
180 if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
181 fatal_f("unknown alg %s", alg);
183 * If we have a @cert-authority marker in known_hosts then
184 * prefer all certificate algorithms.
186 if (sshkey_type_is_cert(ktype) &&
187 lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
188 ALG_APPEND(first, alg);
191 /* If the key appears in known_hosts then prefer it */
192 if (lookup_key_in_hostkeys_by_type(hostkeys,
193 sshkey_type_plain(ktype),
194 sshkey_ecdsa_nid_from_name(alg), NULL)) {
195 ALG_APPEND(first, alg);
198 /* Otherwise, put it last */
199 ALG_APPEND(last, alg);
202 xasprintf(&ret, "%s%s%s", first,
203 (*first == '\0' || *last == '\0') ? "" : ",", last);
205 debug3_f("prefer hostkeyalgs: %s", first);
207 debug3_f("no algorithms matched; accept original");
214 free_hostkeys(hostkeys);
220 ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port,
221 const struct ssh_conn_info *cinfo)
223 char *myproposal[PROPOSAL_MAX];
224 char *all_key, *hkalgs = NULL;
225 int r, use_known_hosts_order = 0;
228 xxx_hostaddr = hostaddr;
229 xxx_conn_info = cinfo;
231 if (options.rekey_limit || options.rekey_interval)
232 ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
233 options.rekey_interval);
236 * If the user has not specified HostkeyAlgorithms, or has only
237 * appended or removed algorithms from that list then prefer algorithms
238 * that are in the list that are supported by known_hosts keys.
240 if (options.hostkeyalgorithms == NULL ||
241 options.hostkeyalgorithms[0] == '-' ||
242 options.hostkeyalgorithms[0] == '+')
243 use_known_hosts_order = 1;
245 /* Expand or fill in HostkeyAlgorithms */
246 all_key = sshkey_alg_list(0, 0, 1, ',');
247 if ((r = kex_assemble_names(&options.hostkeyalgorithms,
248 kex_default_pk_alg(), all_key)) != 0)
249 fatal_fr(r, "kex_assemble_namelist");
252 if (use_known_hosts_order)
253 hkalgs = order_hostkeyalgs(host, hostaddr, port, cinfo);
255 kex_proposal_populate_entries(ssh, myproposal,
256 options.kex_algorithms, options.ciphers, options.macs,
257 compression_alg_list(options.compression),
258 hkalgs ? hkalgs : options.hostkeyalgorithms);
262 /* start key exchange */
263 if ((r = kex_setup(ssh, myproposal)) != 0)
264 fatal_r(r, "kex_setup");
266 ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
267 ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
268 ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
269 ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
270 ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
271 ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
272 ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
273 # ifdef OPENSSL_HAS_ECC
274 ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
277 ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
278 ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
279 ssh->kex->verify_host_key=&verify_host_key_callback;
281 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
282 kex_proposal_free_entries(myproposal);
285 /* send 1st encrypted/maced/compressed message */
286 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
287 (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
288 (r = sshpkt_send(ssh)) != 0 ||
289 (r = ssh_packet_write_wait(ssh)) != 0)
290 fatal_fr(r, "send packet");
298 typedef struct cauthctxt Authctxt;
299 typedef struct cauthmethod Authmethod;
300 typedef struct identity Identity;
301 typedef struct idlist Idlist;
304 TAILQ_ENTRY(identity) next;
305 int agent_fd; /* >=0 if agent supports key */
306 struct sshkey *key; /* public/private key */
307 char *filename; /* comment for agent-only keys */
309 int isprivate; /* key points to the private key */
312 TAILQ_HEAD(idlist, identity);
315 const char *server_user;
316 const char *local_user;
319 struct cauthmethod *method;
320 sig_atomic_t success;
324 gss_OID_set gss_supported_mechs;
331 Sensitive *sensitive;
332 char *oktypes, *ktypes;
333 const char *active_ktype;
334 /* kbd-interactive */
344 char *name; /* string to compare against server's list */
345 int (*userauth)(struct ssh *ssh);
346 void (*cleanup)(struct ssh *ssh);
347 int *enabled; /* flag in option struct that enables method */
348 int *batch_flag; /* flag in option struct that disables method */
351 static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
352 static int input_userauth_success(int, u_int32_t, struct ssh *);
353 static int input_userauth_failure(int, u_int32_t, struct ssh *);
354 static int input_userauth_banner(int, u_int32_t, struct ssh *);
355 static int input_userauth_error(int, u_int32_t, struct ssh *);
356 static int input_userauth_info_req(int, u_int32_t, struct ssh *);
357 static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
358 static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
360 static int userauth_none(struct ssh *);
361 static int userauth_pubkey(struct ssh *);
362 static int userauth_passwd(struct ssh *);
363 static int userauth_kbdint(struct ssh *);
364 static int userauth_hostbased(struct ssh *);
367 static int userauth_gssapi(struct ssh *);
368 static void userauth_gssapi_cleanup(struct ssh *);
369 static int input_gssapi_response(int type, u_int32_t, struct ssh *);
370 static int input_gssapi_token(int type, u_int32_t, struct ssh *);
371 static int input_gssapi_error(int, u_int32_t, struct ssh *);
372 static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
375 void userauth(struct ssh *, char *);
377 static void pubkey_cleanup(struct ssh *);
378 static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
379 static void pubkey_prepare(struct ssh *, Authctxt *);
380 static void pubkey_reset(Authctxt *);
381 static struct sshkey *load_identity_file(Identity *);
383 static Authmethod *authmethod_get(char *authlist);
384 static Authmethod *authmethod_lookup(const char *name);
385 static char *authmethods_get(void);
387 Authmethod authmethods[] = {
391 userauth_gssapi_cleanup,
392 &options.gss_authentication,
398 &options.hostbased_authentication,
403 &options.pubkey_authentication,
405 {"keyboard-interactive",
408 &options.kbd_interactive_authentication,
409 &options.batch_mode},
413 &options.password_authentication,
414 &options.batch_mode},
420 {NULL, NULL, NULL, NULL, NULL}
424 ssh_userauth2(struct ssh *ssh, const char *local_user,
425 const char *server_user, char *host, Sensitive *sensitive)
430 if (options.preferred_authentications == NULL)
431 options.preferred_authentications = authmethods_get();
433 /* setup authentication context */
434 memset(&authctxt, 0, sizeof(authctxt));
435 authctxt.server_user = server_user;
436 authctxt.local_user = local_user;
437 authctxt.host = host;
438 authctxt.service = "ssh-connection"; /* service name */
439 authctxt.success = 0;
440 authctxt.method = authmethod_lookup("none");
441 authctxt.authlist = NULL;
442 authctxt.methoddata = NULL;
443 authctxt.sensitive = sensitive;
444 authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
445 authctxt.info_req_seen = 0;
446 authctxt.attempt_kbdint = 0;
447 authctxt.attempt_passwd = 0;
449 authctxt.gss_supported_mechs = NULL;
450 authctxt.mech_tried = 0;
452 authctxt.agent_fd = -1;
453 if (authctxt.method == NULL)
454 fatal_f("internal error: cannot send userauth none request");
456 if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
457 (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
458 (r = sshpkt_send(ssh)) != 0)
459 fatal_fr(r, "send packet");
461 ssh->authctxt = &authctxt;
462 ssh_dispatch_init(ssh, &input_userauth_error);
463 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, kex_input_ext_info);
464 ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
465 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
468 if (authctxt.gss_supported_mechs != NULL) {
471 gss_release_oid_set(&ms, &authctxt.gss_supported_mechs);
472 authctxt.gss_supported_mechs = NULL;
475 ssh->authctxt = NULL;
477 ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
479 if (!authctxt.success)
480 fatal("Authentication failed.");
481 if (ssh_packet_connection_is_on_socket(ssh)) {
482 verbose("Authenticated to %s ([%s]:%d) using \"%s\".", host,
483 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
484 authctxt.method->name);
486 verbose("Authenticated to %s (via proxy) using \"%s\".", host,
487 authctxt.method->name);
492 input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
496 if (ssh_packet_remaining(ssh) > 0) {
499 if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
501 debug2("service_accept: %s", reply);
504 debug2("buggy server: service_accept w/o service");
506 if ((r = sshpkt_get_end(ssh)) != 0)
508 debug("SSH2_MSG_SERVICE_ACCEPT received");
510 /* initial userauth request */
513 /* accept EXT_INFO at any time during userauth */
514 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, ssh->kex->ext_info_s ?
515 &kex_input_ext_info : &input_userauth_error);
516 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
517 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
518 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
525 userauth(struct ssh *ssh, char *authlist)
527 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
529 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
530 authctxt->method->cleanup(ssh);
532 free(authctxt->methoddata);
533 authctxt->methoddata = NULL;
534 if (authlist == NULL) {
535 authlist = authctxt->authlist;
537 free(authctxt->authlist);
538 authctxt->authlist = authlist;
541 Authmethod *method = authmethod_get(authlist);
543 fatal("%s@%s: Permission denied (%s).",
544 authctxt->server_user, authctxt->host, authlist);
545 authctxt->method = method;
547 /* reset the per method handler */
548 ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
549 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
551 /* and try new method */
552 if (method->userauth(ssh) != 0) {
553 debug2("we sent a %s packet, wait for reply", method->name);
556 debug2("we did not send a packet, disable method");
557 method->enabled = NULL;
563 input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
565 fatal_f("bad message during authentication: type %d", type);
570 input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
576 debug3_f("entering");
577 if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
578 (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
580 if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
581 fmprintf(stderr, "%s", msg);
589 input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
591 Authctxt *authctxt = ssh->authctxt;
593 if (authctxt == NULL)
594 fatal_f("no authentication context");
595 free(authctxt->authlist);
596 authctxt->authlist = NULL;
597 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
598 authctxt->method->cleanup(ssh);
599 free(authctxt->methoddata);
600 authctxt->methoddata = NULL;
601 authctxt->success = 1; /* break out */
602 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, dispatch_protocol_error);
608 input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
610 Authctxt *authctxt = ssh->authctxt;
612 if (authctxt == NULL)
613 fatal_f("no authentication context");
615 fatal("Unexpected authentication success during %s.",
616 authctxt->method->name);
622 input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
624 Authctxt *authctxt = ssh->authctxt;
625 char *authlist = NULL;
628 if (authctxt == NULL)
629 fatal("input_userauth_failure: no authentication context");
631 if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
632 sshpkt_get_u8(ssh, &partial) != 0 ||
633 sshpkt_get_end(ssh) != 0)
637 verbose("Authenticated using \"%s\" with partial success.",
638 authctxt->method->name);
640 pubkey_reset(authctxt);
642 debug("Authentications that can continue: %s", authlist);
644 userauth(ssh, authlist);
652 * Format an identity for logging including filename, key type, fingerprint
653 * and location (agent, etc.). Caller must free.
656 format_identity(Identity *id)
658 char *fp = NULL, *ret = NULL;
659 const char *note = "";
661 if (id->key != NULL) {
662 fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
666 if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
668 else if (sshkey_is_sk(id->key))
669 note = " authenticator";
671 xasprintf(&ret, "%s %s%s%s%s%s%s",
673 id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
675 id->userprovided ? " explicit" : "", note,
676 id->agent_fd != -1 ? " agent" : "");
682 input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
684 Authctxt *authctxt = ssh->authctxt;
685 struct sshkey *key = NULL;
687 int pktype, found = 0, sent = 0;
689 char *pkalg = NULL, *fp = NULL, *ident = NULL;
690 u_char *pkblob = NULL;
693 if (authctxt == NULL)
694 fatal("input_userauth_pk_ok: no authentication context");
696 if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
697 (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
698 (r = sshpkt_get_end(ssh)) != 0)
701 if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
702 debug_f("server sent unknown pkalg %s", pkalg);
705 if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
706 debug_r(r, "no key from blob. pkalg %s", pkalg);
709 if (key->type != pktype) {
710 error("input_userauth_pk_ok: type mismatch "
711 "for decoded key (received %d, expected %d)",
717 * search keys in the reverse order, because last candidate has been
718 * moved to the end of the queue. this also avoids confusion by
721 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
722 if (sshkey_equal(key, id->key)) {
727 if (!found || id == NULL) {
728 fp = sshkey_fingerprint(key, options.fingerprint_hash,
730 error_f("server replied with unknown key: %s %s",
731 sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
734 ident = format_identity(id);
735 debug("Server accepts key: %s", ident);
736 sent = sign_and_send_pubkey(ssh, id);
745 /* try another method if we did not send a packet */
746 if (r == 0 && sent == 0)
753 userauth_gssapi(struct ssh *ssh)
755 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
756 Gssctxt *gssctxt = NULL;
761 /* Try one GSSAPI method at a time, rather than sending them all at
764 if (authctxt->gss_supported_mechs == NULL)
765 gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
767 /* Check to see whether the mechanism is usable before we offer it */
768 while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
770 mech = &authctxt->gss_supported_mechs->
771 elements[authctxt->mech_tried];
772 /* My DER encoding requires length<128 */
773 if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
774 mech, authctxt->host)) {
775 ok = 1; /* Mechanism works */
777 authctxt->mech_tried++;
781 if (!ok || mech == NULL)
784 authctxt->methoddata=(void *)gssctxt;
786 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
787 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
788 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
789 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
790 (r = sshpkt_put_u32(ssh, 1)) != 0 ||
791 (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
792 (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
793 (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
794 (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
795 (r = sshpkt_send(ssh)) != 0)
796 fatal_fr(r, "send packet");
798 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
799 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
800 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
801 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
803 authctxt->mech_tried++; /* Move along to next candidate */
809 userauth_gssapi_cleanup(struct ssh *ssh)
811 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
812 Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
814 ssh_gssapi_delete_ctx(&gssctxt);
815 authctxt->methoddata = NULL;
819 process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
821 Authctxt *authctxt = ssh->authctxt;
822 Gssctxt *gssctxt = authctxt->methoddata;
823 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
824 gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
825 gss_buffer_desc gssbuf;
826 OM_uint32 status, ms, flags;
829 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
830 recv_tok, &send_tok, &flags);
832 if (send_tok.length > 0) {
833 u_char type = GSS_ERROR(status) ?
834 SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
835 SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
837 if ((r = sshpkt_start(ssh, type)) != 0 ||
838 (r = sshpkt_put_string(ssh, send_tok.value,
839 send_tok.length)) != 0 ||
840 (r = sshpkt_send(ssh)) != 0)
841 fatal_fr(r, "send %u packet", type);
843 gss_release_buffer(&ms, &send_tok);
846 if (status == GSS_S_COMPLETE) {
847 /* send either complete or MIC, depending on mechanism */
848 if (!(flags & GSS_C_INTEG_FLAG)) {
849 if ((r = sshpkt_start(ssh,
850 SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
851 (r = sshpkt_send(ssh)) != 0)
852 fatal_fr(r, "send completion");
856 if ((b = sshbuf_new()) == NULL)
857 fatal_f("sshbuf_new failed");
858 ssh_gssapi_buildmic(b, authctxt->server_user,
859 authctxt->service, "gssapi-with-mic",
860 ssh->kex->session_id);
862 if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
863 fatal_f("sshbuf_mutable_ptr failed");
864 gssbuf.length = sshbuf_len(b);
866 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
868 if (!GSS_ERROR(status)) {
869 if ((r = sshpkt_start(ssh,
870 SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
871 (r = sshpkt_put_string(ssh, mic.value,
873 (r = sshpkt_send(ssh)) != 0)
874 fatal_fr(r, "send MIC");
878 gss_release_buffer(&ms, &mic);
886 input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
888 Authctxt *authctxt = ssh->authctxt;
894 if (authctxt == NULL)
895 fatal("input_gssapi_response: no authentication context");
896 gssctxt = authctxt->methoddata;
899 if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
903 oidv[0] != SSH_GSS_OIDTYPE ||
904 oidv[1] != oidlen - 2) {
905 debug("Badly encoded mechanism OID received");
910 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
911 fatal("Server returned different OID than expected");
913 if ((r = sshpkt_get_end(ssh)) != 0)
916 if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
917 /* Start again with next method on list */
918 debug("Trying to start again");
930 input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
932 Authctxt *authctxt = ssh->authctxt;
933 gss_buffer_desc recv_tok;
939 if (authctxt == NULL)
940 fatal("input_gssapi_response: no authentication context");
942 if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
943 (r = sshpkt_get_end(ssh)) != 0)
947 recv_tok.length = len;
948 status = process_gssapi_token(ssh, &recv_tok);
950 /* Start again with the next method in the list */
951 if (GSS_ERROR(status)) {
962 input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
964 Authctxt *authctxt = ssh->authctxt;
966 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
967 gss_buffer_desc recv_tok;
973 if (authctxt == NULL)
974 fatal("input_gssapi_response: no authentication context");
975 gssctxt = authctxt->methoddata;
977 if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
978 (r = sshpkt_get_end(ssh)) != 0) {
983 /* Stick it into GSSAPI and see what it says */
985 recv_tok.length = len;
986 (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
987 &recv_tok, &send_tok, NULL);
989 gss_release_buffer(&ms, &send_tok);
991 /* Server will be returning a failed packet after this one */
996 input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1002 if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1003 (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1004 (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1005 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1007 r = sshpkt_get_end(ssh);
1008 debug("Server GSSAPI Error:\n%s", msg);
1017 userauth_none(struct ssh *ssh)
1019 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1022 /* initial userauth request */
1023 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1024 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1025 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1026 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1027 (r = sshpkt_send(ssh)) != 0)
1028 fatal_fr(r, "send packet");
1033 userauth_passwd(struct ssh *ssh)
1035 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1036 char *password, *prompt = NULL;
1037 const char *host = options.host_key_alias ? options.host_key_alias :
1041 if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1044 if (authctxt->attempt_passwd != 1)
1045 error("Permission denied, please try again.");
1047 xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1048 password = read_passphrase(prompt, 0);
1049 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1050 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1051 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1052 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1053 (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1054 (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1055 (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1056 (r = sshpkt_send(ssh)) != 0)
1057 fatal_fr(r, "send packet");
1060 if (password != NULL)
1061 freezero(password, strlen(password));
1063 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1064 &input_userauth_passwd_changereq);
1070 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1073 input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1075 Authctxt *authctxt = ssh->authctxt;
1076 char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1081 debug2("input_userauth_passwd_changereq");
1083 if (authctxt == NULL)
1084 fatal("input_userauth_passwd_changereq: "
1085 "no authentication context");
1086 host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1088 if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1089 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1091 if (strlen(info) > 0)
1093 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1094 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1095 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1096 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1097 (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1100 snprintf(prompt, sizeof(prompt),
1101 "Enter %.30s@%.128s's old password: ",
1102 authctxt->server_user, host);
1103 password = read_passphrase(prompt, 0);
1104 if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1107 freezero(password, strlen(password));
1109 while (password == NULL) {
1110 snprintf(prompt, sizeof(prompt),
1111 "Enter %.30s@%.128s's new password: ",
1112 authctxt->server_user, host);
1113 password = read_passphrase(prompt, RP_ALLOW_EOF);
1114 if (password == NULL) {
1119 snprintf(prompt, sizeof(prompt),
1120 "Retype %.30s@%.128s's new password: ",
1121 authctxt->server_user, host);
1122 retype = read_passphrase(prompt, 0);
1123 if (strcmp(password, retype) != 0) {
1124 freezero(password, strlen(password));
1125 logit("Mismatch; try again, EOF to quit.");
1128 freezero(retype, strlen(retype));
1130 if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1131 (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1132 (r = sshpkt_send(ssh)) != 0)
1135 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1136 &input_userauth_passwd_changereq);
1140 freezero(password, strlen(password));
1147 * Select an algorithm for publickey signatures.
1148 * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1150 * Call with ssh==NULL to ignore server-sig-algs extension list and
1151 * only attempt with the key's base signature type.
1154 key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1156 char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1157 const char *server_sig_algs;
1160 * The signature algorithm will only differ from the key algorithm
1161 * for RSA keys/certs and when the server advertises support for
1162 * newer (SHA2) algorithms.
1164 if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1165 (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1166 (key->type == KEY_RSA_CERT && (ssh->compat & SSH_BUG_SIGTYPE))) {
1167 /* Filter base key signature alg against our configuration */
1168 return match_list(sshkey_ssh_name(key),
1169 options.pubkey_accepted_algos, NULL);
1173 * Workaround OpenSSH 7.4 bug: this version supports RSA/SHA-2 but
1174 * fails to advertise it via SSH2_MSG_EXT_INFO.
1176 server_sig_algs = ssh->kex->server_sig_algs;
1177 if (key->type == KEY_RSA && (ssh->compat & SSH_BUG_SIGTYPE74))
1178 server_sig_algs = "rsa-sha2-256,rsa-sha2-512";
1181 * For RSA keys/certs, since these might have a different sig type:
1182 * find the first entry in PubkeyAcceptedAlgorithms of the right type
1183 * that also appears in the supported signature algorithms list from
1186 oallowed = allowed = xstrdup(options.pubkey_accepted_algos);
1187 while ((cp = strsep(&allowed, ",")) != NULL) {
1188 if (sshkey_type_from_name(cp) != key->type)
1190 tmp = match_list(sshkey_sigalg_by_name(cp),
1191 server_sig_algs, NULL);
1203 identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1204 const u_char *data, size_t datalen, u_int compat, const char *alg)
1206 struct sshkey *sign_key = NULL, *prv = NULL;
1207 int is_agent = 0, retried = 0, r = SSH_ERR_INTERNAL_ERROR;
1208 struct notifier_ctx *notifier = NULL;
1209 char *fp = NULL, *pin = NULL, *prompt = NULL;
1214 /* The agent supports this key. */
1215 if (id->key != NULL && id->agent_fd != -1) {
1216 return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1217 data, datalen, alg, compat);
1221 * We have already loaded the private key or the private key is
1222 * stored in external hardware.
1224 if (id->key != NULL &&
1225 (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1229 /* Load the private key from the file. */
1230 if ((prv = load_identity_file(id)) == NULL)
1231 return SSH_ERR_KEY_NOT_FOUND;
1232 if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1233 error_f("private key %s contents do not match public",
1235 r = SSH_ERR_KEY_NOT_FOUND;
1241 /* Prompt for touch for non-agent FIDO keys that request UP */
1242 if (!is_agent && sshkey_is_sk(sign_key) &&
1243 (sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1244 /* XXX should batch mode just skip these? */
1245 if ((fp = sshkey_fingerprint(sign_key,
1246 options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
1247 fatal_f("fingerprint failed");
1248 notifier = notify_start(options.batch_mode,
1249 "Confirm user presence for key %s %s",
1250 sshkey_type(sign_key), fp);
1253 if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1254 alg, options.sk_provider, pin, compat)) != 0) {
1255 debug_fr(r, "sshkey_sign");
1256 if (!retried && pin == NULL && !is_agent &&
1257 sshkey_is_sk(sign_key) &&
1258 r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1259 notify_complete(notifier, NULL);
1261 xasprintf(&prompt, "Enter PIN for %s key %s: ",
1262 sshkey_type(sign_key), id->filename);
1263 pin = read_passphrase(prompt, 0);
1271 * PKCS#11 tokens may not support all signature algorithms,
1272 * so check what we get back.
1274 if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1275 debug_fr(r, "sshkey_check_sigtype");
1283 freezero(pin, strlen(pin));
1284 notify_complete(notifier, r == 0 ? "User presence confirmed" : NULL);
1290 id_filename_matches(Identity *id, Identity *private_id)
1292 static const char * const suffixes[] = { ".pub", "-cert.pub", NULL };
1293 size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1296 if (strcmp(id->filename, private_id->filename) == 0)
1298 for (i = 0; suffixes[i]; i++) {
1299 slen = strlen(suffixes[i]);
1300 if (len > slen && plen == len - slen &&
1301 strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1302 memcmp(id->filename, private_id->filename, plen) == 0)
1309 sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1311 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1312 struct sshbuf *b = NULL;
1313 Identity *private_id, *sign_id = NULL;
1314 u_char *signature = NULL;
1315 size_t slen = 0, skip = 0;
1316 int r, fallback_sigtype, sent = 0;
1317 char *alg = NULL, *fp = NULL;
1318 const char *loc = "", *method = "publickey";
1321 /* prefer host-bound pubkey signatures if supported by server */
1322 if ((ssh->kex->flags & KEX_HAS_PUBKEY_HOSTBOUND) != 0 &&
1323 (options.pubkey_authentication & SSH_PUBKEY_AUTH_HBOUND) != 0) {
1325 method = "publickey-hostbound-v00@openssh.com";
1328 if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1329 SSH_FP_DEFAULT)) == NULL)
1332 debug3_f("using %s with %s %s", method, sshkey_type(id->key), fp);
1335 * If the key is an certificate, try to find a matching private key
1336 * and use it to complete the signature.
1337 * If no such private key exists, fall back to trying the certificate
1338 * key itself in case it has a private half already loaded.
1339 * This will try to set sign_id to the private key that will perform
1342 if (sshkey_is_cert(id->key)) {
1343 TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1344 if (sshkey_equal_public(id->key, private_id->key) &&
1345 id->key->type != private_id->key->type) {
1346 sign_id = private_id;
1351 * Exact key matches are preferred, but also allow
1352 * filename matches for non-PKCS#11/agent keys that
1353 * didn't load public keys. This supports the case
1354 * of keeping just a private key file and public
1355 * certificate on disk.
1357 if (sign_id == NULL &&
1358 !id->isprivate && id->agent_fd == -1 &&
1359 (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1360 TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1361 if (private_id->key == NULL &&
1362 id_filename_matches(id, private_id)) {
1363 sign_id = private_id;
1368 if (sign_id != NULL) {
1369 debug2_f("using private key \"%s\"%s for "
1370 "certificate", sign_id->filename,
1371 sign_id->agent_fd != -1 ? " from agent" : "");
1373 debug_f("no separate private key for certificate "
1374 "\"%s\"", id->filename);
1379 * If the above didn't select another identity to do the signing
1380 * then default to the one we started with.
1382 if (sign_id == NULL)
1385 /* assemble and sign data */
1386 for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1390 if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1391 id->key)) == NULL) {
1392 error_f("no mutual signature supported");
1395 debug3_f("signing using %s %s", alg, fp);
1398 if ((b = sshbuf_new()) == NULL)
1399 fatal_f("sshbuf_new failed");
1400 if (ssh->compat & SSH_OLD_SESSIONID) {
1401 if ((r = sshbuf_putb(b, ssh->kex->session_id)) != 0)
1402 fatal_fr(r, "sshbuf_putb");
1404 if ((r = sshbuf_put_stringb(b,
1405 ssh->kex->session_id)) != 0)
1406 fatal_fr(r, "sshbuf_put_stringb");
1408 skip = sshbuf_len(b);
1409 if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1410 (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1411 (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1412 (r = sshbuf_put_cstring(b, method)) != 0 ||
1413 (r = sshbuf_put_u8(b, 1)) != 0 ||
1414 (r = sshbuf_put_cstring(b, alg)) != 0 ||
1415 (r = sshkey_puts(id->key, b)) != 0) {
1416 fatal_fr(r, "assemble signed data");
1419 if (ssh->kex->initial_hostkey == NULL) {
1420 fatal_f("internal error: initial hostkey "
1423 if ((r = sshkey_puts(ssh->kex->initial_hostkey, b)) != 0)
1424 fatal_fr(r, "assemble %s hostkey", method);
1426 /* generate signature */
1427 r = identity_sign(sign_id, &signature, &slen,
1428 sshbuf_ptr(b), sshbuf_len(b), ssh->compat, alg);
1431 else if (r == SSH_ERR_KEY_NOT_FOUND)
1432 goto out; /* soft failure */
1433 else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1434 !fallback_sigtype) {
1435 if (sign_id->agent_fd != -1)
1437 else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1439 logit("%skey %s %s returned incorrect signature type",
1440 loc, sshkey_type(id->key), fp);
1443 error_fr(r, "signing failed for %s \"%s\"%s",
1444 sshkey_type(sign_id->key), sign_id->filename,
1445 id->agent_fd != -1 ? " from agent" : "");
1448 if (slen == 0 || signature == NULL) /* shouldn't happen */
1449 fatal_f("no signature");
1451 /* append signature */
1452 if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1453 fatal_fr(r, "append signature");
1456 sshbuf_dump(b, stderr);
1458 /* skip session id and packet type */
1459 if ((r = sshbuf_consume(b, skip + 1)) != 0)
1460 fatal_fr(r, "consume");
1462 /* put remaining data from buffer into packet */
1463 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1464 (r = sshpkt_putb(ssh, b)) != 0 ||
1465 (r = sshpkt_send(ssh)) != 0)
1466 fatal_fr(r, "enqueue request");
1475 freezero(signature, slen);
1480 send_pubkey_test(struct ssh *ssh, Identity *id)
1482 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1483 u_char *blob = NULL;
1489 if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1490 debug_f("no mutual signature algorithm");
1494 if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1495 /* we cannot handle this key */
1496 debug3_f("cannot handle key");
1499 /* register callback for USERAUTH_PK_OK message */
1500 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1502 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1503 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1504 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1505 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1506 (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1507 (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1508 (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1509 (r = sshpkt_send(ssh)) != 0)
1510 fatal_fr(r, "send packet");
1519 static struct sshkey *
1520 load_identity_file(Identity *id)
1522 struct sshkey *private = NULL;
1523 char prompt[300], *passphrase, *comment;
1527 if (stat(id->filename, &st) == -1) {
1528 do_log2(id->userprovided ?
1529 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1530 "no such identity: %s: %s", id->filename, strerror(errno));
1533 snprintf(prompt, sizeof prompt,
1534 "Enter passphrase for key '%.100s': ", id->filename);
1535 for (i = 0; i <= options.number_of_password_prompts; i++) {
1539 passphrase = read_passphrase(prompt, 0);
1540 if (*passphrase == '\0') {
1541 debug2("no passphrase given, try next key");
1546 switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1547 passphrase, &private, &comment))) {
1550 case SSH_ERR_KEY_WRONG_PASSPHRASE:
1551 if (options.batch_mode) {
1556 debug2("bad passphrase given, try again...");
1558 case SSH_ERR_SYSTEM_ERROR:
1559 if (errno == ENOENT) {
1560 debug2_r(r, "Load key \"%s\"", id->filename);
1566 error_r(r, "Load key \"%s\"", id->filename);
1570 if (private != NULL && sshkey_is_sk(private) &&
1571 options.sk_provider == NULL) {
1572 debug("key \"%s\" is an authenticator-hosted key, "
1573 "but no provider specified", id->filename);
1574 sshkey_free(private);
1578 if (!quit && (r = sshkey_check_rsa_length(private,
1579 options.required_rsa_size)) != 0) {
1580 debug_fr(r, "Skipping key %s", id->filename);
1581 sshkey_free(private);
1585 if (!quit && private != NULL && id->agent_fd == -1 &&
1586 !(id->key && id->isprivate))
1587 maybe_add_key_to_agent(id->filename, private, comment,
1590 freezero(passphrase, strlen(passphrase));
1592 if (private != NULL || quit)
1599 key_type_allowed_by_config(struct sshkey *key)
1601 if (match_pattern_list(sshkey_ssh_name(key),
1602 options.pubkey_accepted_algos, 0) == 1)
1605 /* RSA keys/certs might be allowed by alternate signature types */
1606 switch (key->type) {
1608 if (match_pattern_list("rsa-sha2-512",
1609 options.pubkey_accepted_algos, 0) == 1)
1611 if (match_pattern_list("rsa-sha2-256",
1612 options.pubkey_accepted_algos, 0) == 1)
1616 if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1617 options.pubkey_accepted_algos, 0) == 1)
1619 if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1620 options.pubkey_accepted_algos, 0) == 1)
1627 /* obtain a list of keys from the agent */
1629 get_agent_identities(struct ssh *ssh, int *agent_fdp,
1630 struct ssh_identitylist **idlistp)
1633 struct ssh_identitylist *idlist;
1635 if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1636 if (r != SSH_ERR_AGENT_NOT_PRESENT)
1637 debug_fr(r, "ssh_get_authentication_socket");
1640 if ((r = ssh_agent_bind_hostkey(agent_fd, ssh->kex->initial_hostkey,
1641 ssh->kex->session_id, ssh->kex->initial_sig, 0)) == 0)
1642 debug_f("bound agent to hostkey");
1644 debug2_fr(r, "ssh_agent_bind_hostkey");
1646 if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1647 debug_fr(r, "ssh_fetch_identitylist");
1652 *agent_fdp = agent_fd;
1654 debug_f("agent returned %zu keys", idlist->nkeys);
1659 * try keys in the following order:
1660 * 1. certificates listed in the config file
1661 * 2. other input certificates
1662 * 3. agent keys that are found in the config file
1663 * 4. other agent keys
1664 * 5. keys that are only listed in the config file
1667 pubkey_prepare(struct ssh *ssh, Authctxt *authctxt)
1669 struct identity *id, *id2, *tmp;
1670 struct idlist agent, files, *preferred;
1672 int disallowed, agent_fd = -1, i, r, found;
1674 struct ssh_identitylist *idlist;
1677 TAILQ_INIT(&agent); /* keys from the agent */
1678 TAILQ_INIT(&files); /* keys from the config file */
1679 preferred = &authctxt->keys;
1680 TAILQ_INIT(preferred); /* preferred order of keys */
1682 /* list of keys stored in the filesystem and PKCS#11 */
1683 for (i = 0; i < options.num_identity_files; i++) {
1684 key = options.identity_keys[i];
1685 if (key && key->cert &&
1686 key->cert->type != SSH2_CERT_TYPE_USER) {
1687 debug_f("ignoring certificate %s: not a user "
1688 "certificate", options.identity_files[i]);
1691 if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1692 debug_f("ignoring authenticator-hosted key %s as no "
1693 "SecurityKeyProvider has been specified",
1694 options.identity_files[i]);
1697 options.identity_keys[i] = NULL;
1698 id = xcalloc(1, sizeof(*id));
1701 id->filename = xstrdup(options.identity_files[i]);
1702 id->userprovided = options.identity_file_userprovided[i];
1703 TAILQ_INSERT_TAIL(&files, id, next);
1705 /* list of certificates specified by user */
1706 for (i = 0; i < options.num_certificate_files; i++) {
1707 key = options.certificates[i];
1708 if (!sshkey_is_cert(key) || key->cert == NULL ||
1709 key->cert->type != SSH2_CERT_TYPE_USER) {
1710 debug_f("ignoring certificate %s: not a user "
1711 "certificate", options.identity_files[i]);
1714 if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1715 debug_f("ignoring authenticator-hosted key "
1716 "certificate %s as no "
1717 "SecurityKeyProvider has been specified",
1718 options.identity_files[i]);
1721 id = xcalloc(1, sizeof(*id));
1724 id->filename = xstrdup(options.certificate_files[i]);
1725 id->userprovided = options.certificate_file_userprovided[i];
1726 TAILQ_INSERT_TAIL(preferred, id, next);
1728 /* list of keys supported by the agent */
1729 if ((r = get_agent_identities(ssh, &agent_fd, &idlist)) == 0) {
1730 for (j = 0; j < idlist->nkeys; j++) {
1731 if ((r = sshkey_check_rsa_length(idlist->keys[j],
1732 options.required_rsa_size)) != 0) {
1733 debug_fr(r, "ignoring %s agent key",
1734 sshkey_ssh_name(idlist->keys[j]));
1738 TAILQ_FOREACH(id, &files, next) {
1740 * agent keys from the config file are
1743 if (sshkey_equal(idlist->keys[j], id->key)) {
1744 TAILQ_REMOVE(&files, id, next);
1745 TAILQ_INSERT_TAIL(preferred, id, next);
1746 id->agent_fd = agent_fd;
1751 if (!found && !options.identities_only) {
1752 id = xcalloc(1, sizeof(*id));
1753 /* XXX "steals" key/comment from idlist */
1754 id->key = idlist->keys[j];
1755 id->filename = idlist->comments[j];
1756 idlist->keys[j] = NULL;
1757 idlist->comments[j] = NULL;
1758 id->agent_fd = agent_fd;
1759 TAILQ_INSERT_TAIL(&agent, id, next);
1762 ssh_free_identitylist(idlist);
1763 /* append remaining agent keys */
1764 TAILQ_CONCAT(preferred, &agent, next);
1765 authctxt->agent_fd = agent_fd;
1767 /* Prefer PKCS11 keys that are explicitly listed */
1768 TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1769 if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1772 TAILQ_FOREACH(id2, &files, next) {
1773 if (id2->key == NULL ||
1774 (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1776 if (sshkey_equal(id->key, id2->key)) {
1777 TAILQ_REMOVE(&files, id, next);
1778 TAILQ_INSERT_TAIL(preferred, id, next);
1783 /* If IdentitiesOnly set and key not found then don't use it */
1784 if (!found && options.identities_only) {
1785 TAILQ_REMOVE(&files, id, next);
1786 freezero(id, sizeof(*id));
1789 /* append remaining keys from the config file */
1790 TAILQ_CONCAT(preferred, &files, next);
1791 /* finally, filter by PubkeyAcceptedAlgorithms */
1792 TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1795 if (id->key == NULL)
1797 if (!key_type_allowed_by_config(id->key)) {
1798 debug("Skipping %s key %s - corresponding algorithm "
1799 "not in PubkeyAcceptedAlgorithms",
1800 sshkey_ssh_name(id->key), id->filename);
1802 } else if (ssh->kex->server_sig_algs != NULL &&
1803 (cp = key_sig_algorithm(ssh, id->key)) == NULL) {
1804 debug("Skipping %s key %s - corresponding algorithm "
1805 "not supported by server",
1806 sshkey_ssh_name(id->key), id->filename);
1813 TAILQ_REMOVE(preferred, id, next);
1814 sshkey_free(id->key);
1816 memset(id, 0, sizeof(*id));
1818 /* List the keys we plan on using */
1819 TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1820 ident = format_identity(id);
1821 debug("Will attempt key: %s", ident);
1828 pubkey_cleanup(struct ssh *ssh)
1830 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1833 if (authctxt->agent_fd != -1) {
1834 ssh_close_authentication_socket(authctxt->agent_fd);
1835 authctxt->agent_fd = -1;
1837 for (id = TAILQ_FIRST(&authctxt->keys); id;
1838 id = TAILQ_FIRST(&authctxt->keys)) {
1839 TAILQ_REMOVE(&authctxt->keys, id, next);
1840 sshkey_free(id->key);
1847 pubkey_reset(Authctxt *authctxt)
1851 TAILQ_FOREACH(id, &authctxt->keys, next)
1856 userauth_pubkey(struct ssh *ssh)
1858 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1862 static int prepared;
1865 pubkey_prepare(ssh, authctxt);
1869 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1872 /* move key to the end of the queue */
1873 TAILQ_REMOVE(&authctxt->keys, id, next);
1874 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1876 * send a test message if we have the public key. for
1877 * encrypted keys we cannot do this and have to load the
1878 * private key instead
1880 if (id->key != NULL) {
1881 ident = format_identity(id);
1882 debug("Offering public key: %s", ident);
1884 sent = send_pubkey_test(ssh, id);
1886 debug("Trying private key: %s", id->filename);
1887 id->key = load_identity_file(id);
1888 if (id->key != NULL) {
1889 if (id->key != NULL) {
1891 sent = sign_and_send_pubkey(ssh, id);
1893 sshkey_free(id->key);
1905 * Send userauth request message specifying keyboard-interactive method.
1908 userauth_kbdint(struct ssh *ssh)
1910 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1913 if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1915 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1916 if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1917 debug3("userauth_kbdint: disable: no info_req_seen");
1918 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1922 debug2("userauth_kbdint");
1923 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1924 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1925 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1926 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1927 (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1928 (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1929 options.kbd_interactive_devices : "")) != 0 ||
1930 (r = sshpkt_send(ssh)) != 0)
1931 fatal_fr(r, "send packet");
1933 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1938 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1941 input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1943 Authctxt *authctxt = ssh->authctxt;
1944 char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1945 char *display_prompt = NULL, *response = NULL;
1947 u_int num_prompts, i;
1950 debug2_f("entering");
1952 if (authctxt == NULL)
1953 fatal_f("no authentication context");
1955 authctxt->info_req_seen = 1;
1957 if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1958 (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1959 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1961 if (strlen(name) > 0)
1963 if (strlen(inst) > 0)
1966 if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1969 * Begin to build info response packet based on prompts requested.
1970 * We commit to providing the correct number of responses, so if
1971 * further on we run into a problem that prevents this, we have to
1972 * be sure and clean this up and send a correct error response.
1974 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1975 (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1978 debug2_f("num_prompts %d", num_prompts);
1979 for (i = 0; i < num_prompts; i++) {
1980 if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1981 (r = sshpkt_get_u8(ssh, &echo)) != 0)
1983 if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1984 authctxt->server_user, options.host_key_alias ?
1985 options.host_key_alias : authctxt->host, prompt) == -1)
1986 fatal_f("asmprintf failed");
1987 response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1988 if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1990 freezero(response, strlen(response));
1992 free(display_prompt);
1993 display_prompt = response = prompt = NULL;
1995 /* done with parsing incoming message. */
1996 if ((r = sshpkt_get_end(ssh)) != 0 ||
1997 (r = sshpkt_add_padding(ssh, 64)) != 0)
1999 r = sshpkt_send(ssh);
2002 freezero(response, strlen(response));
2004 free(display_prompt);
2012 ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
2013 const u_char *data, size_t datalen)
2018 int r, to[2], from[2], status;
2019 int sock = ssh_packet_get_connection_in(ssh);
2020 u_char rversion = 0, version = 2;
2021 void (*osigchld)(int);
2026 if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
2027 error_f("not installed: %s", strerror(errno));
2030 if (fflush(stdout) != 0) {
2031 error_f("fflush: %s", strerror(errno));
2034 if (pipe(to) == -1) {
2035 error_f("pipe: %s", strerror(errno));
2038 if (pipe(from) == -1) {
2039 error_f("pipe: %s", strerror(errno));
2042 if ((pid = fork()) == -1) {
2043 error_f("fork: %s", strerror(errno));
2046 osigchld = ssh_signal(SIGCHLD, SIG_DFL);
2049 if (dup2(from[1], STDOUT_FILENO) == -1)
2050 fatal_f("dup2: %s", strerror(errno));
2052 if (dup2(to[0], STDIN_FILENO) == -1)
2053 fatal_f("dup2: %s", strerror(errno));
2057 if (dup2(sock, STDERR_FILENO + 1) == -1)
2058 fatal_f("dup2: %s", strerror(errno));
2059 sock = STDERR_FILENO + 1;
2060 if (fcntl(sock, F_SETFD, 0) == -1) /* keep the socket on exec */
2061 debug3_f("fcntl F_SETFD: %s", strerror(errno));
2062 closefrom(sock + 1);
2064 debug3_f("[child] pid=%ld, exec %s",
2065 (long)getpid(), _PATH_SSH_KEY_SIGN);
2066 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
2067 fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
2072 sock = STDERR_FILENO + 1;
2074 if ((b = sshbuf_new()) == NULL)
2075 fatal_f("sshbuf_new failed");
2076 /* send # of sock, data to be signed */
2077 if ((r = sshbuf_put_u32(b, sock)) != 0 ||
2078 (r = sshbuf_put_string(b, data, datalen)) != 0)
2079 fatal_fr(r, "buffer error");
2080 if (ssh_msg_send(to[1], version, b) == -1)
2081 fatal_f("couldn't send request");
2083 r = ssh_msg_recv(from[0], b);
2087 error_f("no reply");
2092 while (waitpid(pid, &status, 0) == -1) {
2093 if (errno != EINTR) {
2094 error_f("waitpid %ld: %s", (long)pid, strerror(errno));
2098 if (!WIFEXITED(status)) {
2099 error_f("exited abnormally");
2102 if (WEXITSTATUS(status) != 0) {
2103 error_f("exited with status %d", WEXITSTATUS(status));
2106 if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
2107 error_fr(r, "buffer error");
2110 if (rversion != version) {
2111 error_f("bad version");
2114 if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
2115 error_fr(r, "buffer error");
2117 ssh_signal(SIGCHLD, osigchld);
2121 ssh_signal(SIGCHLD, osigchld);
2128 userauth_hostbased(struct ssh *ssh)
2130 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
2131 struct sshkey *private = NULL;
2132 struct sshbuf *b = NULL;
2133 u_char *sig = NULL, *keyblob = NULL;
2134 char *fp = NULL, *chost = NULL, *lname = NULL;
2135 size_t siglen = 0, keylen = 0;
2136 int i, r, success = 0;
2138 if (authctxt->ktypes == NULL) {
2139 authctxt->oktypes = xstrdup(options.hostbased_accepted_algos);
2140 authctxt->ktypes = authctxt->oktypes;
2144 * Work through each listed type pattern in HostbasedAcceptedAlgorithms,
2145 * trying each hostkey that matches the type in turn.
2148 if (authctxt->active_ktype == NULL)
2149 authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2150 if (authctxt->active_ktype == NULL ||
2151 *authctxt->active_ktype == '\0')
2153 debug3_f("trying key type %s", authctxt->active_ktype);
2155 /* check for a useful key */
2157 for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2158 if (authctxt->sensitive->keys[i] == NULL ||
2159 authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2161 if (!sshkey_match_keyname_to_sigalgs(
2162 sshkey_ssh_name(authctxt->sensitive->keys[i]),
2163 authctxt->active_ktype))
2165 /* we take and free the key */
2166 private = authctxt->sensitive->keys[i];
2167 authctxt->sensitive->keys[i] = NULL;
2171 if (private != NULL)
2173 /* No more keys of this type; advance */
2174 authctxt->active_ktype = NULL;
2176 if (private == NULL) {
2177 free(authctxt->oktypes);
2178 authctxt->oktypes = authctxt->ktypes = NULL;
2179 authctxt->active_ktype = NULL;
2180 debug("No more client hostkeys for hostbased authentication.");
2184 if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2185 SSH_FP_DEFAULT)) == NULL) {
2186 error_f("sshkey_fingerprint failed");
2189 debug_f("trying hostkey %s %s using sigalg %s",
2190 sshkey_ssh_name(private), fp, authctxt->active_ktype);
2192 /* figure out a name for the client host */
2193 lname = get_local_name(ssh_packet_get_connection_in(ssh));
2194 if (lname == NULL) {
2195 error_f("cannot get local ipaddr/name");
2199 /* XXX sshbuf_put_stringf? */
2200 xasprintf(&chost, "%s.", lname);
2201 debug2_f("chost %s", chost);
2203 /* construct data */
2204 if ((b = sshbuf_new()) == NULL) {
2205 error_f("sshbuf_new failed");
2208 if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
2209 error_fr(r, "sshkey_to_blob");
2212 if ((r = sshbuf_put_stringb(b, ssh->kex->session_id)) != 0 ||
2213 (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2214 (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
2215 (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
2216 (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
2217 (r = sshbuf_put_cstring(b, authctxt->active_ktype)) != 0 ||
2218 (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2219 (r = sshbuf_put_cstring(b, chost)) != 0 ||
2220 (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
2221 error_fr(r, "buffer error");
2226 sshbuf_dump(b, stderr);
2228 if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2229 sshbuf_ptr(b), sshbuf_len(b))) != 0) {
2230 error("sign using hostkey %s %s failed",
2231 sshkey_ssh_name(private), fp);
2234 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2235 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2236 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2237 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
2238 (r = sshpkt_put_cstring(ssh, authctxt->active_ktype)) != 0 ||
2239 (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2240 (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2241 (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2242 (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2243 (r = sshpkt_send(ssh)) != 0) {
2244 error_fr(r, "packet error");
2251 freezero(sig, siglen);
2256 sshkey_free(private);
2262 /* find auth method */
2265 * given auth method name, if configurable options permit this method fill
2266 * in auth_ident field and return true, otherwise return false.
2269 authmethod_is_enabled(Authmethod *method)
2273 /* return false if options indicate this method is disabled */
2274 if (method->enabled == NULL || *method->enabled == 0)
2276 /* return false if batch mode is enabled but method needs interactive mode */
2277 if (method->batch_flag != NULL && *method->batch_flag != 0)
2283 authmethod_lookup(const char *name)
2285 Authmethod *method = NULL;
2287 for (method = authmethods; method->name != NULL; method++)
2288 if (strcmp(name, method->name) == 0)
2290 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2294 /* XXX internal state */
2295 static Authmethod *current = NULL;
2296 static char *supported = NULL;
2297 static char *preferred = NULL;
2300 * Given the authentication method list sent by the server, return the
2301 * next method we should try. If the server initially sends a nil list,
2302 * use a built-in default list.
2305 authmethod_get(char *authlist)
2310 /* Use a suitable default if we're passed a nil list. */
2311 if (authlist == NULL || strlen(authlist) == 0)
2312 authlist = options.preferred_authentications;
2314 if (supported == NULL || strcmp(authlist, supported) != 0) {
2315 debug3("start over, passed a different list %s", authlist);
2317 supported = xstrdup(authlist);
2318 preferred = options.preferred_authentications;
2319 debug3("preferred %s", preferred);
2321 } else if (current != NULL && authmethod_is_enabled(current))
2325 if ((name = match_list(preferred, supported, &next)) == NULL) {
2326 debug("No more authentication methods to try.");
2331 debug3("authmethod_lookup %s", name);
2332 debug3("remaining preferred: %s", preferred);
2333 if ((current = authmethod_lookup(name)) != NULL &&
2334 authmethod_is_enabled(current)) {
2335 debug3("authmethod_is_enabled %s", name);
2336 debug("Next authentication method: %s", name);
2345 authmethods_get(void)
2347 Authmethod *method = NULL;
2352 if ((b = sshbuf_new()) == NULL)
2353 fatal_f("sshbuf_new failed");
2354 for (method = authmethods; method->name != NULL; method++) {
2355 if (authmethod_is_enabled(method)) {
2356 if ((r = sshbuf_putf(b, "%s%s",
2357 sshbuf_len(b) ? "," : "", method->name)) != 0)
2358 fatal_fr(r, "buffer error");
2361 if ((list = sshbuf_dup_string(b)) == NULL)
2362 fatal_f("sshbuf_dup_string failed");