1 /* $OpenBSD: sshconnect2.c,v 1.367 2023/08/01 08:15:04 dtucker 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, host);
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 *s, *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 ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
253 fatal_f("kex_names_cat");
255 if (use_known_hosts_order)
256 hkalgs = order_hostkeyalgs(host, hostaddr, port, cinfo);
258 kex_proposal_populate_entries(ssh, myproposal, s, options.ciphers,
259 options.macs, compression_alg_list(options.compression),
260 hkalgs ? hkalgs : options.hostkeyalgorithms);
264 /* start key exchange */
265 if ((r = kex_setup(ssh, myproposal)) != 0)
266 fatal_r(r, "kex_setup");
268 ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
269 ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
270 ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
271 ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
272 ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
273 ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
274 ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
275 # ifdef OPENSSL_HAS_ECC
276 ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
279 ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
280 ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
281 ssh->kex->verify_host_key=&verify_host_key_callback;
283 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
285 /* remove ext-info from the KEX proposals for rekeying */
286 free(myproposal[PROPOSAL_KEX_ALGS]);
287 myproposal[PROPOSAL_KEX_ALGS] =
288 compat_kex_proposal(ssh, options.kex_algorithms);
289 if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
290 fatal_r(r, "kex_prop2buf");
293 /* send 1st encrypted/maced/compressed message */
294 if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
295 (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
296 (r = sshpkt_send(ssh)) != 0 ||
297 (r = ssh_packet_write_wait(ssh)) != 0)
298 fatal_fr(r, "send packet");
300 kex_proposal_free_entries(myproposal);
307 typedef struct cauthctxt Authctxt;
308 typedef struct cauthmethod Authmethod;
309 typedef struct identity Identity;
310 typedef struct idlist Idlist;
313 TAILQ_ENTRY(identity) next;
314 int agent_fd; /* >=0 if agent supports key */
315 struct sshkey *key; /* public/private key */
316 char *filename; /* comment for agent-only keys */
318 int isprivate; /* key points to the private key */
321 TAILQ_HEAD(idlist, identity);
324 const char *server_user;
325 const char *local_user;
328 struct cauthmethod *method;
329 sig_atomic_t success;
333 gss_OID_set gss_supported_mechs;
340 Sensitive *sensitive;
341 char *oktypes, *ktypes;
342 const char *active_ktype;
343 /* kbd-interactive */
353 char *name; /* string to compare against server's list */
354 int (*userauth)(struct ssh *ssh);
355 void (*cleanup)(struct ssh *ssh);
356 int *enabled; /* flag in option struct that enables method */
357 int *batch_flag; /* flag in option struct that disables method */
360 static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
361 static int input_userauth_success(int, u_int32_t, struct ssh *);
362 static int input_userauth_failure(int, u_int32_t, struct ssh *);
363 static int input_userauth_banner(int, u_int32_t, struct ssh *);
364 static int input_userauth_error(int, u_int32_t, struct ssh *);
365 static int input_userauth_info_req(int, u_int32_t, struct ssh *);
366 static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
367 static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
369 static int userauth_none(struct ssh *);
370 static int userauth_pubkey(struct ssh *);
371 static int userauth_passwd(struct ssh *);
372 static int userauth_kbdint(struct ssh *);
373 static int userauth_hostbased(struct ssh *);
376 static int userauth_gssapi(struct ssh *);
377 static void userauth_gssapi_cleanup(struct ssh *);
378 static int input_gssapi_response(int type, u_int32_t, struct ssh *);
379 static int input_gssapi_token(int type, u_int32_t, struct ssh *);
380 static int input_gssapi_error(int, u_int32_t, struct ssh *);
381 static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
384 void userauth(struct ssh *, char *);
386 static void pubkey_cleanup(struct ssh *);
387 static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
388 static void pubkey_prepare(struct ssh *, Authctxt *);
389 static void pubkey_reset(Authctxt *);
390 static struct sshkey *load_identity_file(Identity *);
392 static Authmethod *authmethod_get(char *authlist);
393 static Authmethod *authmethod_lookup(const char *name);
394 static char *authmethods_get(void);
396 Authmethod authmethods[] = {
400 userauth_gssapi_cleanup,
401 &options.gss_authentication,
407 &options.hostbased_authentication,
412 &options.pubkey_authentication,
414 {"keyboard-interactive",
417 &options.kbd_interactive_authentication,
418 &options.batch_mode},
422 &options.password_authentication,
423 &options.batch_mode},
429 {NULL, NULL, NULL, NULL, NULL}
433 ssh_userauth2(struct ssh *ssh, const char *local_user,
434 const char *server_user, char *host, Sensitive *sensitive)
439 if (options.preferred_authentications == NULL)
440 options.preferred_authentications = authmethods_get();
442 /* setup authentication context */
443 memset(&authctxt, 0, sizeof(authctxt));
444 authctxt.server_user = server_user;
445 authctxt.local_user = local_user;
446 authctxt.host = host;
447 authctxt.service = "ssh-connection"; /* service name */
448 authctxt.success = 0;
449 authctxt.method = authmethod_lookup("none");
450 authctxt.authlist = NULL;
451 authctxt.methoddata = NULL;
452 authctxt.sensitive = sensitive;
453 authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
454 authctxt.info_req_seen = 0;
455 authctxt.attempt_kbdint = 0;
456 authctxt.attempt_passwd = 0;
458 authctxt.gss_supported_mechs = NULL;
459 authctxt.mech_tried = 0;
461 authctxt.agent_fd = -1;
462 pubkey_prepare(ssh, &authctxt);
463 if (authctxt.method == NULL) {
464 fatal_f("internal error: cannot send userauth none request");
467 if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
468 (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
469 (r = sshpkt_send(ssh)) != 0)
470 fatal_fr(r, "send packet");
472 ssh->authctxt = &authctxt;
473 ssh_dispatch_init(ssh, &input_userauth_error);
474 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, kex_input_ext_info);
475 ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
476 ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
478 ssh->authctxt = NULL;
480 ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
482 if (!authctxt.success)
483 fatal("Authentication failed.");
484 if (ssh_packet_connection_is_on_socket(ssh)) {
485 verbose("Authenticated to %s ([%s]:%d) using \"%s\".", host,
486 ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
487 authctxt.method->name);
489 verbose("Authenticated to %s (via proxy) using \"%s\".", host,
490 authctxt.method->name);
495 input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
499 if (ssh_packet_remaining(ssh) > 0) {
502 if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
504 debug2("service_accept: %s", reply);
507 debug2("buggy server: service_accept w/o service");
509 if ((r = sshpkt_get_end(ssh)) != 0)
511 debug("SSH2_MSG_SERVICE_ACCEPT received");
513 /* initial userauth request */
516 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
517 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
518 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
519 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
526 userauth(struct ssh *ssh, char *authlist)
528 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
530 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
531 authctxt->method->cleanup(ssh);
533 free(authctxt->methoddata);
534 authctxt->methoddata = NULL;
535 if (authlist == NULL) {
536 authlist = authctxt->authlist;
538 free(authctxt->authlist);
539 authctxt->authlist = authlist;
542 Authmethod *method = authmethod_get(authlist);
544 fatal("%s@%s: Permission denied (%s).",
545 authctxt->server_user, authctxt->host, authlist);
546 authctxt->method = method;
548 /* reset the per method handler */
549 ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
550 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
552 /* and try new method */
553 if (method->userauth(ssh) != 0) {
554 debug2("we sent a %s packet, wait for reply", method->name);
557 debug2("we did not send a packet, disable method");
558 method->enabled = NULL;
564 input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
566 fatal_f("bad message during authentication: type %d", type);
571 input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
577 debug3_f("entering");
578 if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
579 (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
581 if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
582 fmprintf(stderr, "%s", msg);
590 input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
592 Authctxt *authctxt = ssh->authctxt;
594 if (authctxt == NULL)
595 fatal_f("no authentication context");
596 free(authctxt->authlist);
597 authctxt->authlist = NULL;
598 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
599 authctxt->method->cleanup(ssh);
600 free(authctxt->methoddata);
601 authctxt->methoddata = NULL;
602 authctxt->success = 1; /* break out */
603 ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, dispatch_protocol_error);
609 input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
611 Authctxt *authctxt = ssh->authctxt;
613 if (authctxt == NULL)
614 fatal_f("no authentication context");
616 fatal("Unexpected authentication success during %s.",
617 authctxt->method->name);
623 input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
625 Authctxt *authctxt = ssh->authctxt;
626 char *authlist = NULL;
629 if (authctxt == NULL)
630 fatal("input_userauth_failure: no authentication context");
632 if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
633 sshpkt_get_u8(ssh, &partial) != 0 ||
634 sshpkt_get_end(ssh) != 0)
638 verbose("Authenticated using \"%s\" with partial success.",
639 authctxt->method->name);
641 pubkey_reset(authctxt);
643 debug("Authentications that can continue: %s", authlist);
645 userauth(ssh, authlist);
653 * Format an identity for logging including filename, key type, fingerprint
654 * and location (agent, etc.). Caller must free.
657 format_identity(Identity *id)
659 char *fp = NULL, *ret = NULL;
660 const char *note = "";
662 if (id->key != NULL) {
663 fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
667 if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
669 else if (sshkey_is_sk(id->key))
670 note = " authenticator";
672 xasprintf(&ret, "%s %s%s%s%s%s%s",
674 id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
676 id->userprovided ? " explicit" : "", note,
677 id->agent_fd != -1 ? " agent" : "");
683 input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
685 Authctxt *authctxt = ssh->authctxt;
686 struct sshkey *key = NULL;
688 int pktype, found = 0, sent = 0;
690 char *pkalg = NULL, *fp = NULL, *ident = NULL;
691 u_char *pkblob = NULL;
694 if (authctxt == NULL)
695 fatal("input_userauth_pk_ok: no authentication context");
697 if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
698 (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
699 (r = sshpkt_get_end(ssh)) != 0)
702 if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
703 debug_f("server sent unknown pkalg %s", pkalg);
706 if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
707 debug_r(r, "no key from blob. pkalg %s", pkalg);
710 if (key->type != pktype) {
711 error("input_userauth_pk_ok: type mismatch "
712 "for decoded key (received %d, expected %d)",
718 * search keys in the reverse order, because last candidate has been
719 * moved to the end of the queue. this also avoids confusion by
722 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
723 if (sshkey_equal(key, id->key)) {
728 if (!found || id == NULL) {
729 fp = sshkey_fingerprint(key, options.fingerprint_hash,
731 error_f("server replied with unknown key: %s %s",
732 sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
735 ident = format_identity(id);
736 debug("Server accepts key: %s", ident);
737 sent = sign_and_send_pubkey(ssh, id);
746 /* try another method if we did not send a packet */
747 if (r == 0 && sent == 0)
754 userauth_gssapi(struct ssh *ssh)
756 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
757 Gssctxt *gssctxt = NULL;
762 /* Try one GSSAPI method at a time, rather than sending them all at
765 if (authctxt->gss_supported_mechs == NULL)
766 gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
768 /* Check to see whether the mechanism is usable before we offer it */
769 while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
771 mech = &authctxt->gss_supported_mechs->
772 elements[authctxt->mech_tried];
773 /* My DER encoding requires length<128 */
774 if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
775 mech, authctxt->host)) {
776 ok = 1; /* Mechanism works */
778 authctxt->mech_tried++;
782 if (!ok || mech == NULL)
785 authctxt->methoddata=(void *)gssctxt;
787 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
788 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
789 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
790 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
791 (r = sshpkt_put_u32(ssh, 1)) != 0 ||
792 (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
793 (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
794 (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
795 (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
796 (r = sshpkt_send(ssh)) != 0)
797 fatal_fr(r, "send packet");
799 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
800 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
801 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
802 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
804 authctxt->mech_tried++; /* Move along to next candidate */
810 userauth_gssapi_cleanup(struct ssh *ssh)
812 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
813 Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
815 ssh_gssapi_delete_ctx(&gssctxt);
816 authctxt->methoddata = NULL;
818 free(authctxt->gss_supported_mechs);
819 authctxt->gss_supported_mechs = NULL;
823 process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
825 Authctxt *authctxt = ssh->authctxt;
826 Gssctxt *gssctxt = authctxt->methoddata;
827 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
828 gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
829 gss_buffer_desc gssbuf;
830 OM_uint32 status, ms, flags;
833 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
834 recv_tok, &send_tok, &flags);
836 if (send_tok.length > 0) {
837 u_char type = GSS_ERROR(status) ?
838 SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
839 SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
841 if ((r = sshpkt_start(ssh, type)) != 0 ||
842 (r = sshpkt_put_string(ssh, send_tok.value,
843 send_tok.length)) != 0 ||
844 (r = sshpkt_send(ssh)) != 0)
845 fatal_fr(r, "send %u packet", type);
847 gss_release_buffer(&ms, &send_tok);
850 if (status == GSS_S_COMPLETE) {
851 /* send either complete or MIC, depending on mechanism */
852 if (!(flags & GSS_C_INTEG_FLAG)) {
853 if ((r = sshpkt_start(ssh,
854 SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
855 (r = sshpkt_send(ssh)) != 0)
856 fatal_fr(r, "send completion");
860 if ((b = sshbuf_new()) == NULL)
861 fatal_f("sshbuf_new failed");
862 ssh_gssapi_buildmic(b, authctxt->server_user,
863 authctxt->service, "gssapi-with-mic",
864 ssh->kex->session_id);
866 if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
867 fatal_f("sshbuf_mutable_ptr failed");
868 gssbuf.length = sshbuf_len(b);
870 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
872 if (!GSS_ERROR(status)) {
873 if ((r = sshpkt_start(ssh,
874 SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
875 (r = sshpkt_put_string(ssh, mic.value,
877 (r = sshpkt_send(ssh)) != 0)
878 fatal_fr(r, "send MIC");
882 gss_release_buffer(&ms, &mic);
890 input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
892 Authctxt *authctxt = ssh->authctxt;
898 if (authctxt == NULL)
899 fatal("input_gssapi_response: no authentication context");
900 gssctxt = authctxt->methoddata;
903 if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
907 oidv[0] != SSH_GSS_OIDTYPE ||
908 oidv[1] != oidlen - 2) {
909 debug("Badly encoded mechanism OID received");
914 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
915 fatal("Server returned different OID than expected");
917 if ((r = sshpkt_get_end(ssh)) != 0)
920 if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
921 /* Start again with next method on list */
922 debug("Trying to start again");
934 input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
936 Authctxt *authctxt = ssh->authctxt;
937 gss_buffer_desc recv_tok;
943 if (authctxt == NULL)
944 fatal("input_gssapi_response: no authentication context");
946 if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
947 (r = sshpkt_get_end(ssh)) != 0)
951 recv_tok.length = len;
952 status = process_gssapi_token(ssh, &recv_tok);
954 /* Start again with the next method in the list */
955 if (GSS_ERROR(status)) {
966 input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
968 Authctxt *authctxt = ssh->authctxt;
970 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
971 gss_buffer_desc recv_tok;
977 if (authctxt == NULL)
978 fatal("input_gssapi_response: no authentication context");
979 gssctxt = authctxt->methoddata;
981 if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
982 (r = sshpkt_get_end(ssh)) != 0) {
987 /* Stick it into GSSAPI and see what it says */
989 recv_tok.length = len;
990 (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
991 &recv_tok, &send_tok, NULL);
993 gss_release_buffer(&ms, &send_tok);
995 /* Server will be returning a failed packet after this one */
1000 input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1006 if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1007 (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1008 (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1009 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1011 r = sshpkt_get_end(ssh);
1012 debug("Server GSSAPI Error:\n%s", msg);
1021 userauth_none(struct ssh *ssh)
1023 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1026 /* initial userauth request */
1027 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1028 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1029 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1030 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1031 (r = sshpkt_send(ssh)) != 0)
1032 fatal_fr(r, "send packet");
1037 userauth_passwd(struct ssh *ssh)
1039 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1040 char *password, *prompt = NULL;
1041 const char *host = options.host_key_alias ? options.host_key_alias :
1045 if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1048 if (authctxt->attempt_passwd != 1)
1049 error("Permission denied, please try again.");
1051 xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1052 password = read_passphrase(prompt, 0);
1053 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1054 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1055 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1056 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1057 (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1058 (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1059 (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1060 (r = sshpkt_send(ssh)) != 0)
1061 fatal_fr(r, "send packet");
1064 if (password != NULL)
1065 freezero(password, strlen(password));
1067 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1068 &input_userauth_passwd_changereq);
1074 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1077 input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1079 Authctxt *authctxt = ssh->authctxt;
1080 char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1085 debug2("input_userauth_passwd_changereq");
1087 if (authctxt == NULL)
1088 fatal("input_userauth_passwd_changereq: "
1089 "no authentication context");
1090 host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1092 if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1093 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1095 if (strlen(info) > 0)
1097 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1098 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1099 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1100 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1101 (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1104 snprintf(prompt, sizeof(prompt),
1105 "Enter %.30s@%.128s's old password: ",
1106 authctxt->server_user, host);
1107 password = read_passphrase(prompt, 0);
1108 if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1111 freezero(password, strlen(password));
1113 while (password == NULL) {
1114 snprintf(prompt, sizeof(prompt),
1115 "Enter %.30s@%.128s's new password: ",
1116 authctxt->server_user, host);
1117 password = read_passphrase(prompt, RP_ALLOW_EOF);
1118 if (password == NULL) {
1123 snprintf(prompt, sizeof(prompt),
1124 "Retype %.30s@%.128s's new password: ",
1125 authctxt->server_user, host);
1126 retype = read_passphrase(prompt, 0);
1127 if (strcmp(password, retype) != 0) {
1128 freezero(password, strlen(password));
1129 logit("Mismatch; try again, EOF to quit.");
1132 freezero(retype, strlen(retype));
1134 if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1135 (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1136 (r = sshpkt_send(ssh)) != 0)
1139 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1140 &input_userauth_passwd_changereq);
1144 freezero(password, strlen(password));
1151 * Select an algorithm for publickey signatures.
1152 * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1154 * Call with ssh==NULL to ignore server-sig-algs extension list and
1155 * only attempt with the key's base signature type.
1158 key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1160 char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1161 const char *server_sig_algs;
1164 * The signature algorithm will only differ from the key algorithm
1165 * for RSA keys/certs and when the server advertises support for
1166 * newer (SHA2) algorithms.
1168 if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1169 (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1170 (key->type == KEY_RSA_CERT && (ssh->compat & SSH_BUG_SIGTYPE))) {
1171 /* Filter base key signature alg against our configuration */
1172 return match_list(sshkey_ssh_name(key),
1173 options.pubkey_accepted_algos, NULL);
1177 * Workaround OpenSSH 7.4 bug: this version supports RSA/SHA-2 but
1178 * fails to advertise it via SSH2_MSG_EXT_INFO.
1180 server_sig_algs = ssh->kex->server_sig_algs;
1181 if (key->type == KEY_RSA && (ssh->compat & SSH_BUG_SIGTYPE74))
1182 server_sig_algs = "rsa-sha2-256,rsa-sha2-512";
1185 * For RSA keys/certs, since these might have a different sig type:
1186 * find the first entry in PubkeyAcceptedAlgorithms of the right type
1187 * that also appears in the supported signature algorithms list from
1190 oallowed = allowed = xstrdup(options.pubkey_accepted_algos);
1191 while ((cp = strsep(&allowed, ",")) != NULL) {
1192 if (sshkey_type_from_name(cp) != key->type)
1194 tmp = match_list(sshkey_sigalg_by_name(cp),
1195 server_sig_algs, NULL);
1207 identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1208 const u_char *data, size_t datalen, u_int compat, const char *alg)
1210 struct sshkey *sign_key = NULL, *prv = NULL;
1211 int is_agent = 0, retried = 0, r = SSH_ERR_INTERNAL_ERROR;
1212 struct notifier_ctx *notifier = NULL;
1213 char *fp = NULL, *pin = NULL, *prompt = NULL;
1218 /* The agent supports this key. */
1219 if (id->key != NULL && id->agent_fd != -1) {
1220 return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1221 data, datalen, alg, compat);
1225 * We have already loaded the private key or the private key is
1226 * stored in external hardware.
1228 if (id->key != NULL &&
1229 (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1233 /* Load the private key from the file. */
1234 if ((prv = load_identity_file(id)) == NULL)
1235 return SSH_ERR_KEY_NOT_FOUND;
1236 if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1237 error_f("private key %s contents do not match public",
1239 r = SSH_ERR_KEY_NOT_FOUND;
1245 /* Prompt for touch for non-agent FIDO keys that request UP */
1246 if (!is_agent && sshkey_is_sk(sign_key) &&
1247 (sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1248 /* XXX should batch mode just skip these? */
1249 if ((fp = sshkey_fingerprint(sign_key,
1250 options.fingerprint_hash, SSH_FP_DEFAULT)) == NULL)
1251 fatal_f("fingerprint failed");
1252 notifier = notify_start(options.batch_mode,
1253 "Confirm user presence for key %s %s",
1254 sshkey_type(sign_key), fp);
1257 if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1258 alg, options.sk_provider, pin, compat)) != 0) {
1259 debug_fr(r, "sshkey_sign");
1260 if (!retried && pin == NULL && !is_agent &&
1261 sshkey_is_sk(sign_key) &&
1262 r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1263 notify_complete(notifier, NULL);
1265 xasprintf(&prompt, "Enter PIN for %s key %s: ",
1266 sshkey_type(sign_key), id->filename);
1267 pin = read_passphrase(prompt, 0);
1275 * PKCS#11 tokens may not support all signature algorithms,
1276 * so check what we get back.
1278 if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1279 debug_fr(r, "sshkey_check_sigtype");
1287 freezero(pin, strlen(pin));
1288 notify_complete(notifier, r == 0 ? "User presence confirmed" : NULL);
1294 id_filename_matches(Identity *id, Identity *private_id)
1296 static const char * const suffixes[] = { ".pub", "-cert.pub", NULL };
1297 size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1300 if (strcmp(id->filename, private_id->filename) == 0)
1302 for (i = 0; suffixes[i]; i++) {
1303 slen = strlen(suffixes[i]);
1304 if (len > slen && plen == len - slen &&
1305 strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1306 memcmp(id->filename, private_id->filename, plen) == 0)
1313 sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1315 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1316 struct sshbuf *b = NULL;
1317 Identity *private_id, *sign_id = NULL;
1318 u_char *signature = NULL;
1319 size_t slen = 0, skip = 0;
1320 int r, fallback_sigtype, sent = 0;
1321 char *alg = NULL, *fp = NULL;
1322 const char *loc = "", *method = "publickey";
1325 /* prefer host-bound pubkey signatures if supported by server */
1326 if ((ssh->kex->flags & KEX_HAS_PUBKEY_HOSTBOUND) != 0 &&
1327 (options.pubkey_authentication & SSH_PUBKEY_AUTH_HBOUND) != 0) {
1329 method = "publickey-hostbound-v00@openssh.com";
1332 if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1333 SSH_FP_DEFAULT)) == NULL)
1336 debug3_f("using %s with %s %s", method, sshkey_type(id->key), fp);
1339 * If the key is an certificate, try to find a matching private key
1340 * and use it to complete the signature.
1341 * If no such private key exists, fall back to trying the certificate
1342 * key itself in case it has a private half already loaded.
1343 * This will try to set sign_id to the private key that will perform
1346 if (sshkey_is_cert(id->key)) {
1347 TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1348 if (sshkey_equal_public(id->key, private_id->key) &&
1349 id->key->type != private_id->key->type) {
1350 sign_id = private_id;
1355 * Exact key matches are preferred, but also allow
1356 * filename matches for non-PKCS#11/agent keys that
1357 * didn't load public keys. This supports the case
1358 * of keeping just a private key file and public
1359 * certificate on disk.
1361 if (sign_id == NULL &&
1362 !id->isprivate && id->agent_fd == -1 &&
1363 (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1364 TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1365 if (private_id->key == NULL &&
1366 id_filename_matches(id, private_id)) {
1367 sign_id = private_id;
1372 if (sign_id != NULL) {
1373 debug2_f("using private key \"%s\"%s for "
1374 "certificate", sign_id->filename,
1375 sign_id->agent_fd != -1 ? " from agent" : "");
1377 debug_f("no separate private key for certificate "
1378 "\"%s\"", id->filename);
1383 * If the above didn't select another identity to do the signing
1384 * then default to the one we started with.
1386 if (sign_id == NULL)
1389 /* assemble and sign data */
1390 for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1394 if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1395 id->key)) == NULL) {
1396 error_f("no mutual signature supported");
1399 debug3_f("signing using %s %s", alg, fp);
1402 if ((b = sshbuf_new()) == NULL)
1403 fatal_f("sshbuf_new failed");
1404 if (ssh->compat & SSH_OLD_SESSIONID) {
1405 if ((r = sshbuf_putb(b, ssh->kex->session_id)) != 0)
1406 fatal_fr(r, "sshbuf_putb");
1408 if ((r = sshbuf_put_stringb(b,
1409 ssh->kex->session_id)) != 0)
1410 fatal_fr(r, "sshbuf_put_stringb");
1412 skip = sshbuf_len(b);
1413 if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1414 (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1415 (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1416 (r = sshbuf_put_cstring(b, method)) != 0 ||
1417 (r = sshbuf_put_u8(b, 1)) != 0 ||
1418 (r = sshbuf_put_cstring(b, alg)) != 0 ||
1419 (r = sshkey_puts(id->key, b)) != 0) {
1420 fatal_fr(r, "assemble signed data");
1423 if (ssh->kex->initial_hostkey == NULL) {
1424 fatal_f("internal error: initial hostkey "
1427 if ((r = sshkey_puts(ssh->kex->initial_hostkey, b)) != 0)
1428 fatal_fr(r, "assemble %s hostkey", method);
1430 /* generate signature */
1431 r = identity_sign(sign_id, &signature, &slen,
1432 sshbuf_ptr(b), sshbuf_len(b), ssh->compat, alg);
1435 else if (r == SSH_ERR_KEY_NOT_FOUND)
1436 goto out; /* soft failure */
1437 else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1438 !fallback_sigtype) {
1439 if (sign_id->agent_fd != -1)
1441 else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1443 logit("%skey %s %s returned incorrect signature type",
1444 loc, sshkey_type(id->key), fp);
1447 error_fr(r, "signing failed for %s \"%s\"%s",
1448 sshkey_type(sign_id->key), sign_id->filename,
1449 id->agent_fd != -1 ? " from agent" : "");
1452 if (slen == 0 || signature == NULL) /* shouldn't happen */
1453 fatal_f("no signature");
1455 /* append signature */
1456 if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1457 fatal_fr(r, "append signature");
1460 sshbuf_dump(b, stderr);
1462 /* skip session id and packet type */
1463 if ((r = sshbuf_consume(b, skip + 1)) != 0)
1464 fatal_fr(r, "consume");
1466 /* put remaining data from buffer into packet */
1467 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1468 (r = sshpkt_putb(ssh, b)) != 0 ||
1469 (r = sshpkt_send(ssh)) != 0)
1470 fatal_fr(r, "enqueue request");
1479 freezero(signature, slen);
1484 send_pubkey_test(struct ssh *ssh, Identity *id)
1486 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1487 u_char *blob = NULL;
1493 if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1494 debug_f("no mutual signature algorithm");
1498 if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1499 /* we cannot handle this key */
1500 debug3_f("cannot handle key");
1503 /* register callback for USERAUTH_PK_OK message */
1504 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1506 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1507 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1508 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1509 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1510 (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1511 (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1512 (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1513 (r = sshpkt_send(ssh)) != 0)
1514 fatal_fr(r, "send packet");
1523 static struct sshkey *
1524 load_identity_file(Identity *id)
1526 struct sshkey *private = NULL;
1527 char prompt[300], *passphrase, *comment;
1531 if (stat(id->filename, &st) == -1) {
1532 do_log2(id->userprovided ?
1533 SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1534 "no such identity: %s: %s", id->filename, strerror(errno));
1537 snprintf(prompt, sizeof prompt,
1538 "Enter passphrase for key '%.100s': ", id->filename);
1539 for (i = 0; i <= options.number_of_password_prompts; i++) {
1543 passphrase = read_passphrase(prompt, 0);
1544 if (*passphrase == '\0') {
1545 debug2("no passphrase given, try next key");
1550 switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1551 passphrase, &private, &comment))) {
1554 case SSH_ERR_KEY_WRONG_PASSPHRASE:
1555 if (options.batch_mode) {
1560 debug2("bad passphrase given, try again...");
1562 case SSH_ERR_SYSTEM_ERROR:
1563 if (errno == ENOENT) {
1564 debug2_r(r, "Load key \"%s\"", id->filename);
1570 error_r(r, "Load key \"%s\"", id->filename);
1574 if (private != NULL && sshkey_is_sk(private) &&
1575 options.sk_provider == NULL) {
1576 debug("key \"%s\" is an authenticator-hosted key, "
1577 "but no provider specified", id->filename);
1578 sshkey_free(private);
1582 if (!quit && (r = sshkey_check_rsa_length(private,
1583 options.required_rsa_size)) != 0) {
1584 debug_fr(r, "Skipping key %s", id->filename);
1585 sshkey_free(private);
1589 if (!quit && private != NULL && id->agent_fd == -1 &&
1590 !(id->key && id->isprivate))
1591 maybe_add_key_to_agent(id->filename, private, comment,
1594 freezero(passphrase, strlen(passphrase));
1596 if (private != NULL || quit)
1603 key_type_allowed_by_config(struct sshkey *key)
1605 if (match_pattern_list(sshkey_ssh_name(key),
1606 options.pubkey_accepted_algos, 0) == 1)
1609 /* RSA keys/certs might be allowed by alternate signature types */
1610 switch (key->type) {
1612 if (match_pattern_list("rsa-sha2-512",
1613 options.pubkey_accepted_algos, 0) == 1)
1615 if (match_pattern_list("rsa-sha2-256",
1616 options.pubkey_accepted_algos, 0) == 1)
1620 if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1621 options.pubkey_accepted_algos, 0) == 1)
1623 if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1624 options.pubkey_accepted_algos, 0) == 1)
1631 /* obtain a list of keys from the agent */
1633 get_agent_identities(struct ssh *ssh, int *agent_fdp,
1634 struct ssh_identitylist **idlistp)
1637 struct ssh_identitylist *idlist;
1639 if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1640 if (r != SSH_ERR_AGENT_NOT_PRESENT)
1641 debug_fr(r, "ssh_get_authentication_socket");
1644 if ((r = ssh_agent_bind_hostkey(agent_fd, ssh->kex->initial_hostkey,
1645 ssh->kex->session_id, ssh->kex->initial_sig, 0)) == 0)
1646 debug_f("bound agent to hostkey");
1648 debug2_fr(r, "ssh_agent_bind_hostkey");
1650 if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1651 debug_fr(r, "ssh_fetch_identitylist");
1656 *agent_fdp = agent_fd;
1658 debug_f("agent returned %zu keys", idlist->nkeys);
1663 * try keys in the following order:
1664 * 1. certificates listed in the config file
1665 * 2. other input certificates
1666 * 3. agent keys that are found in the config file
1667 * 4. other agent keys
1668 * 5. keys that are only listed in the config file
1671 pubkey_prepare(struct ssh *ssh, Authctxt *authctxt)
1673 struct identity *id, *id2, *tmp;
1674 struct idlist agent, files, *preferred;
1676 int agent_fd = -1, i, r, found;
1678 struct ssh_identitylist *idlist;
1681 TAILQ_INIT(&agent); /* keys from the agent */
1682 TAILQ_INIT(&files); /* keys from the config file */
1683 preferred = &authctxt->keys;
1684 TAILQ_INIT(preferred); /* preferred order of keys */
1686 /* list of keys stored in the filesystem and PKCS#11 */
1687 for (i = 0; i < options.num_identity_files; i++) {
1688 key = options.identity_keys[i];
1689 if (key && key->cert &&
1690 key->cert->type != SSH2_CERT_TYPE_USER) {
1691 debug_f("ignoring certificate %s: not a user "
1692 "certificate", options.identity_files[i]);
1695 if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1696 debug_f("ignoring authenticator-hosted key %s as no "
1697 "SecurityKeyProvider has been specified",
1698 options.identity_files[i]);
1701 options.identity_keys[i] = NULL;
1702 id = xcalloc(1, sizeof(*id));
1705 id->filename = xstrdup(options.identity_files[i]);
1706 id->userprovided = options.identity_file_userprovided[i];
1707 TAILQ_INSERT_TAIL(&files, id, next);
1709 /* list of certificates specified by user */
1710 for (i = 0; i < options.num_certificate_files; i++) {
1711 key = options.certificates[i];
1712 if (!sshkey_is_cert(key) || key->cert == NULL ||
1713 key->cert->type != SSH2_CERT_TYPE_USER) {
1714 debug_f("ignoring certificate %s: not a user "
1715 "certificate", options.identity_files[i]);
1718 if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1719 debug_f("ignoring authenticator-hosted key "
1720 "certificate %s as no "
1721 "SecurityKeyProvider has been specified",
1722 options.identity_files[i]);
1725 id = xcalloc(1, sizeof(*id));
1728 id->filename = xstrdup(options.certificate_files[i]);
1729 id->userprovided = options.certificate_file_userprovided[i];
1730 TAILQ_INSERT_TAIL(preferred, id, next);
1732 /* list of keys supported by the agent */
1733 if ((r = get_agent_identities(ssh, &agent_fd, &idlist)) == 0) {
1734 for (j = 0; j < idlist->nkeys; j++) {
1735 if ((r = sshkey_check_rsa_length(idlist->keys[j],
1736 options.required_rsa_size)) != 0) {
1737 debug_fr(r, "ignoring %s agent key",
1738 sshkey_ssh_name(idlist->keys[j]));
1742 TAILQ_FOREACH(id, &files, next) {
1744 * agent keys from the config file are
1747 if (sshkey_equal(idlist->keys[j], id->key)) {
1748 TAILQ_REMOVE(&files, id, next);
1749 TAILQ_INSERT_TAIL(preferred, id, next);
1750 id->agent_fd = agent_fd;
1755 if (!found && !options.identities_only) {
1756 id = xcalloc(1, sizeof(*id));
1757 /* XXX "steals" key/comment from idlist */
1758 id->key = idlist->keys[j];
1759 id->filename = idlist->comments[j];
1760 idlist->keys[j] = NULL;
1761 idlist->comments[j] = NULL;
1762 id->agent_fd = agent_fd;
1763 TAILQ_INSERT_TAIL(&agent, id, next);
1766 ssh_free_identitylist(idlist);
1767 /* append remaining agent keys */
1768 TAILQ_CONCAT(preferred, &agent, next);
1769 authctxt->agent_fd = agent_fd;
1771 /* Prefer PKCS11 keys that are explicitly listed */
1772 TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1773 if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1776 TAILQ_FOREACH(id2, &files, next) {
1777 if (id2->key == NULL ||
1778 (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1780 if (sshkey_equal(id->key, id2->key)) {
1781 TAILQ_REMOVE(&files, id, next);
1782 TAILQ_INSERT_TAIL(preferred, id, next);
1787 /* If IdentitiesOnly set and key not found then don't use it */
1788 if (!found && options.identities_only) {
1789 TAILQ_REMOVE(&files, id, next);
1790 freezero(id, sizeof(*id));
1793 /* append remaining keys from the config file */
1794 TAILQ_CONCAT(preferred, &files, next);
1795 /* finally, filter by PubkeyAcceptedAlgorithms */
1796 TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1797 if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1798 debug("Skipping %s key %s - "
1799 "corresponding algo not in PubkeyAcceptedAlgorithms",
1800 sshkey_ssh_name(id->key), id->filename);
1801 TAILQ_REMOVE(preferred, id, next);
1802 sshkey_free(id->key);
1804 memset(id, 0, sizeof(*id));
1808 /* List the keys we plan on using */
1809 TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1810 ident = format_identity(id);
1811 debug("Will attempt key: %s", ident);
1818 pubkey_cleanup(struct ssh *ssh)
1820 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1823 if (authctxt->agent_fd != -1) {
1824 ssh_close_authentication_socket(authctxt->agent_fd);
1825 authctxt->agent_fd = -1;
1827 for (id = TAILQ_FIRST(&authctxt->keys); id;
1828 id = TAILQ_FIRST(&authctxt->keys)) {
1829 TAILQ_REMOVE(&authctxt->keys, id, next);
1830 sshkey_free(id->key);
1837 pubkey_reset(Authctxt *authctxt)
1841 TAILQ_FOREACH(id, &authctxt->keys, next)
1846 userauth_pubkey(struct ssh *ssh)
1848 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1853 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1856 /* move key to the end of the queue */
1857 TAILQ_REMOVE(&authctxt->keys, id, next);
1858 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1860 * send a test message if we have the public key. for
1861 * encrypted keys we cannot do this and have to load the
1862 * private key instead
1864 if (id->key != NULL) {
1865 ident = format_identity(id);
1866 debug("Offering public key: %s", ident);
1868 sent = send_pubkey_test(ssh, id);
1870 debug("Trying private key: %s", id->filename);
1871 id->key = load_identity_file(id);
1872 if (id->key != NULL) {
1873 if (id->key != NULL) {
1875 sent = sign_and_send_pubkey(ssh, id);
1877 sshkey_free(id->key);
1889 * Send userauth request message specifying keyboard-interactive method.
1892 userauth_kbdint(struct ssh *ssh)
1894 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1897 if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1899 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1900 if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1901 debug3("userauth_kbdint: disable: no info_req_seen");
1902 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1906 debug2("userauth_kbdint");
1907 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1908 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1909 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1910 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1911 (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1912 (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1913 options.kbd_interactive_devices : "")) != 0 ||
1914 (r = sshpkt_send(ssh)) != 0)
1915 fatal_fr(r, "send packet");
1917 ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1922 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1925 input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1927 Authctxt *authctxt = ssh->authctxt;
1928 char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1929 char *display_prompt = NULL, *response = NULL;
1931 u_int num_prompts, i;
1934 debug2_f("entering");
1936 if (authctxt == NULL)
1937 fatal_f("no authentication context");
1939 authctxt->info_req_seen = 1;
1941 if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1942 (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1943 (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1945 if (strlen(name) > 0)
1947 if (strlen(inst) > 0)
1950 if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1953 * Begin to build info response packet based on prompts requested.
1954 * We commit to providing the correct number of responses, so if
1955 * further on we run into a problem that prevents this, we have to
1956 * be sure and clean this up and send a correct error response.
1958 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1959 (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1962 debug2_f("num_prompts %d", num_prompts);
1963 for (i = 0; i < num_prompts; i++) {
1964 if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1965 (r = sshpkt_get_u8(ssh, &echo)) != 0)
1967 if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1968 authctxt->server_user, options.host_key_alias ?
1969 options.host_key_alias : authctxt->host, prompt) == -1)
1970 fatal_f("asmprintf failed");
1971 response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1972 if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1974 freezero(response, strlen(response));
1976 free(display_prompt);
1977 display_prompt = response = prompt = NULL;
1979 /* done with parsing incoming message. */
1980 if ((r = sshpkt_get_end(ssh)) != 0 ||
1981 (r = sshpkt_add_padding(ssh, 64)) != 0)
1983 r = sshpkt_send(ssh);
1986 freezero(response, strlen(response));
1988 free(display_prompt);
1996 ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1997 const u_char *data, size_t datalen)
2002 int r, to[2], from[2], status;
2003 int sock = ssh_packet_get_connection_in(ssh);
2004 u_char rversion = 0, version = 2;
2005 void (*osigchld)(int);
2010 if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
2011 error_f("not installed: %s", strerror(errno));
2014 if (fflush(stdout) != 0) {
2015 error_f("fflush: %s", strerror(errno));
2018 if (pipe(to) == -1) {
2019 error_f("pipe: %s", strerror(errno));
2022 if (pipe(from) == -1) {
2023 error_f("pipe: %s", strerror(errno));
2026 if ((pid = fork()) == -1) {
2027 error_f("fork: %s", strerror(errno));
2030 osigchld = ssh_signal(SIGCHLD, SIG_DFL);
2033 if (dup2(from[1], STDOUT_FILENO) == -1)
2034 fatal_f("dup2: %s", strerror(errno));
2036 if (dup2(to[0], STDIN_FILENO) == -1)
2037 fatal_f("dup2: %s", strerror(errno));
2041 if (dup2(sock, STDERR_FILENO + 1) == -1)
2042 fatal_f("dup2: %s", strerror(errno));
2043 sock = STDERR_FILENO + 1;
2044 if (fcntl(sock, F_SETFD, 0) == -1) /* keep the socket on exec */
2045 debug3_f("fcntl F_SETFD: %s", strerror(errno));
2046 closefrom(sock + 1);
2048 debug3_f("[child] pid=%ld, exec %s",
2049 (long)getpid(), _PATH_SSH_KEY_SIGN);
2050 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
2051 fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
2056 sock = STDERR_FILENO + 1;
2058 if ((b = sshbuf_new()) == NULL)
2059 fatal_f("sshbuf_new failed");
2060 /* send # of sock, data to be signed */
2061 if ((r = sshbuf_put_u32(b, sock)) != 0 ||
2062 (r = sshbuf_put_string(b, data, datalen)) != 0)
2063 fatal_fr(r, "buffer error");
2064 if (ssh_msg_send(to[1], version, b) == -1)
2065 fatal_f("couldn't send request");
2067 r = ssh_msg_recv(from[0], b);
2071 error_f("no reply");
2076 while (waitpid(pid, &status, 0) == -1) {
2077 if (errno != EINTR) {
2078 error_f("waitpid %ld: %s", (long)pid, strerror(errno));
2082 if (!WIFEXITED(status)) {
2083 error_f("exited abnormally");
2086 if (WEXITSTATUS(status) != 0) {
2087 error_f("exited with status %d", WEXITSTATUS(status));
2090 if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
2091 error_fr(r, "buffer error");
2094 if (rversion != version) {
2095 error_f("bad version");
2098 if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
2099 error_fr(r, "buffer error");
2101 ssh_signal(SIGCHLD, osigchld);
2105 ssh_signal(SIGCHLD, osigchld);
2112 userauth_hostbased(struct ssh *ssh)
2114 Authctxt *authctxt = (Authctxt *)ssh->authctxt;
2115 struct sshkey *private = NULL;
2116 struct sshbuf *b = NULL;
2117 u_char *sig = NULL, *keyblob = NULL;
2118 char *fp = NULL, *chost = NULL, *lname = NULL;
2119 size_t siglen = 0, keylen = 0;
2120 int i, r, success = 0;
2122 if (authctxt->ktypes == NULL) {
2123 authctxt->oktypes = xstrdup(options.hostbased_accepted_algos);
2124 authctxt->ktypes = authctxt->oktypes;
2128 * Work through each listed type pattern in HostbasedAcceptedAlgorithms,
2129 * trying each hostkey that matches the type in turn.
2132 if (authctxt->active_ktype == NULL)
2133 authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2134 if (authctxt->active_ktype == NULL ||
2135 *authctxt->active_ktype == '\0')
2137 debug3_f("trying key type %s", authctxt->active_ktype);
2139 /* check for a useful key */
2141 for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2142 if (authctxt->sensitive->keys[i] == NULL ||
2143 authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2145 if (!sshkey_match_keyname_to_sigalgs(
2146 sshkey_ssh_name(authctxt->sensitive->keys[i]),
2147 authctxt->active_ktype))
2149 /* we take and free the key */
2150 private = authctxt->sensitive->keys[i];
2151 authctxt->sensitive->keys[i] = NULL;
2155 if (private != NULL)
2157 /* No more keys of this type; advance */
2158 authctxt->active_ktype = NULL;
2160 if (private == NULL) {
2161 free(authctxt->oktypes);
2162 authctxt->oktypes = authctxt->ktypes = NULL;
2163 authctxt->active_ktype = NULL;
2164 debug("No more client hostkeys for hostbased authentication.");
2168 if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2169 SSH_FP_DEFAULT)) == NULL) {
2170 error_f("sshkey_fingerprint failed");
2173 debug_f("trying hostkey %s %s using sigalg %s",
2174 sshkey_ssh_name(private), fp, authctxt->active_ktype);
2176 /* figure out a name for the client host */
2177 lname = get_local_name(ssh_packet_get_connection_in(ssh));
2178 if (lname == NULL) {
2179 error_f("cannot get local ipaddr/name");
2183 /* XXX sshbuf_put_stringf? */
2184 xasprintf(&chost, "%s.", lname);
2185 debug2_f("chost %s", chost);
2187 /* construct data */
2188 if ((b = sshbuf_new()) == NULL) {
2189 error_f("sshbuf_new failed");
2192 if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
2193 error_fr(r, "sshkey_to_blob");
2196 if ((r = sshbuf_put_stringb(b, ssh->kex->session_id)) != 0 ||
2197 (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2198 (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
2199 (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
2200 (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
2201 (r = sshbuf_put_cstring(b, authctxt->active_ktype)) != 0 ||
2202 (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2203 (r = sshbuf_put_cstring(b, chost)) != 0 ||
2204 (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
2205 error_fr(r, "buffer error");
2210 sshbuf_dump(b, stderr);
2212 if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2213 sshbuf_ptr(b), sshbuf_len(b))) != 0) {
2214 error("sign using hostkey %s %s failed",
2215 sshkey_ssh_name(private), fp);
2218 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2219 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2220 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2221 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
2222 (r = sshpkt_put_cstring(ssh, authctxt->active_ktype)) != 0 ||
2223 (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2224 (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2225 (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2226 (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2227 (r = sshpkt_send(ssh)) != 0) {
2228 error_fr(r, "packet error");
2235 freezero(sig, siglen);
2240 sshkey_free(private);
2246 /* find auth method */
2249 * given auth method name, if configurable options permit this method fill
2250 * in auth_ident field and return true, otherwise return false.
2253 authmethod_is_enabled(Authmethod *method)
2257 /* return false if options indicate this method is disabled */
2258 if (method->enabled == NULL || *method->enabled == 0)
2260 /* return false if batch mode is enabled but method needs interactive mode */
2261 if (method->batch_flag != NULL && *method->batch_flag != 0)
2267 authmethod_lookup(const char *name)
2269 Authmethod *method = NULL;
2271 for (method = authmethods; method->name != NULL; method++)
2272 if (strcmp(name, method->name) == 0)
2274 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2278 /* XXX internal state */
2279 static Authmethod *current = NULL;
2280 static char *supported = NULL;
2281 static char *preferred = NULL;
2284 * Given the authentication method list sent by the server, return the
2285 * next method we should try. If the server initially sends a nil list,
2286 * use a built-in default list.
2289 authmethod_get(char *authlist)
2294 /* Use a suitable default if we're passed a nil list. */
2295 if (authlist == NULL || strlen(authlist) == 0)
2296 authlist = options.preferred_authentications;
2298 if (supported == NULL || strcmp(authlist, supported) != 0) {
2299 debug3("start over, passed a different list %s", authlist);
2301 supported = xstrdup(authlist);
2302 preferred = options.preferred_authentications;
2303 debug3("preferred %s", preferred);
2305 } else if (current != NULL && authmethod_is_enabled(current))
2309 if ((name = match_list(preferred, supported, &next)) == NULL) {
2310 debug("No more authentication methods to try.");
2315 debug3("authmethod_lookup %s", name);
2316 debug3("remaining preferred: %s", preferred);
2317 if ((current = authmethod_lookup(name)) != NULL &&
2318 authmethod_is_enabled(current)) {
2319 debug3("authmethod_is_enabled %s", name);
2320 debug("Next authentication method: %s", name);
2329 authmethods_get(void)
2331 Authmethod *method = NULL;
2336 if ((b = sshbuf_new()) == NULL)
2337 fatal_f("sshbuf_new failed");
2338 for (method = authmethods; method->name != NULL; method++) {
2339 if (authmethod_is_enabled(method)) {
2340 if ((r = sshbuf_putf(b, "%s%s",
2341 sshbuf_len(b) ? "," : "", method->name)) != 0)
2342 fatal_fr(r, "buffer error");
2345 if ((list = sshbuf_dup_string(b)) == NULL)
2346 fatal_f("sshbuf_dup_string failed");