1 /* $OpenBSD: sshconnect2.c,v 1.226 2015/07/30 00:01:34 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>
43 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS)
47 #include "openbsd-compat/sys-queue.h"
58 #include "myproposal.h"
59 #include "sshconnect.h"
70 #include "pathnames.h"
80 extern char *client_version_string;
81 extern char *server_version_string;
82 extern Options options;
88 u_char *session_id2 = NULL;
89 u_int session_id2_len = 0;
92 struct sockaddr *xxx_hostaddr;
95 verify_host_key_callback(Key *hostkey, struct ssh *ssh)
97 if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
98 fatal("Host key verification failed.");
103 order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
105 char *oavail, *avail, *first, *last, *alg, *hostname, *ret;
107 struct hostkeys *hostkeys;
111 /* Find all hostkeys for this hostname */
112 get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
113 hostkeys = init_hostkeys();
114 for (i = 0; i < options.num_user_hostfiles; i++)
115 load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
116 for (i = 0; i < options.num_system_hostfiles; i++)
117 load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
119 oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
120 maxlen = strlen(avail) + 1;
121 first = xmalloc(maxlen);
122 last = xmalloc(maxlen);
123 *first = *last = '\0';
125 #define ALG_APPEND(to, from) \
128 strlcat(to, ",", maxlen); \
129 strlcat(to, from, maxlen); \
132 while ((alg = strsep(&avail, ",")) && *alg != '\0') {
133 if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
134 fatal("%s: unknown alg %s", __func__, alg);
135 if (lookup_key_in_hostkeys_by_type(hostkeys,
136 sshkey_type_plain(ktype), NULL))
137 ALG_APPEND(first, alg);
139 ALG_APPEND(last, alg);
142 xasprintf(&ret, "%s%s%s", first,
143 (*first == '\0' || *last == '\0') ? "" : ",", last);
145 debug3("%s: prefer hostkeyalgs: %s", __func__, first);
151 free_hostkeys(hostkeys);
157 ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
159 char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
164 xxx_hostaddr = hostaddr;
166 myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
167 options.kex_algorithms);
168 myproposal[PROPOSAL_ENC_ALGS_CTOS] =
169 compat_cipher_proposal(options.ciphers);
170 myproposal[PROPOSAL_ENC_ALGS_STOC] =
171 compat_cipher_proposal(options.ciphers);
172 if (options.compression) {
173 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
174 myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
176 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
177 myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
179 myproposal[PROPOSAL_MAC_ALGS_CTOS] =
180 myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
181 if (options.hostkeyalgorithms != NULL) {
182 if (kex_assemble_names(KEX_DEFAULT_PK_ALG,
183 &options.hostkeyalgorithms) != 0)
184 fatal("%s: kex_assemble_namelist", __func__);
185 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
186 compat_pkalg_proposal(options.hostkeyalgorithms);
188 /* Enforce default */
189 options.hostkeyalgorithms = xstrdup(KEX_DEFAULT_PK_ALG);
190 /* Prefer algorithms that we already have keys for */
191 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
192 compat_pkalg_proposal(
193 order_hostkeyalgs(host, hostaddr, port));
196 if (options.rekey_limit || options.rekey_interval)
197 packet_set_rekey_limits((u_int32_t)options.rekey_limit,
198 (time_t)options.rekey_interval);
200 /* start key exchange */
201 if ((r = kex_setup(active_state, myproposal)) != 0)
202 fatal("kex_setup: %s", ssh_err(r));
203 kex = active_state->kex;
205 kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
206 kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
207 kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
208 kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
209 # ifdef OPENSSL_HAS_ECC
210 kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
213 kex->kex[KEX_C25519_SHA256] = kexc25519_client;
214 kex->client_version_string=client_version_string;
215 kex->server_version_string=server_version_string;
216 kex->verify_host_key=&verify_host_key_callback;
218 dispatch_run(DISPATCH_BLOCK, &kex->done, active_state);
220 if (options.use_roaming && !kex->roaming) {
221 debug("Roaming not allowed by server");
222 options.use_roaming = 0;
225 session_id2 = kex->session_id;
226 session_id2_len = kex->session_id_len;
229 /* send 1st encrypted/maced/compressed message */
230 packet_start(SSH2_MSG_IGNORE);
231 packet_put_cstring("markus");
241 typedef struct cauthctxt Authctxt;
242 typedef struct cauthmethod Authmethod;
243 typedef struct identity Identity;
244 typedef struct idlist Idlist;
247 TAILQ_ENTRY(identity) next;
248 int agent_fd; /* >=0 if agent supports key */
249 struct sshkey *key; /* public/private key */
250 char *filename; /* comment for agent-only keys */
252 int isprivate; /* key points to the private key */
255 TAILQ_HEAD(idlist, identity);
258 const char *server_user;
259 const char *local_user;
262 struct cauthmethod *method;
263 sig_atomic_t success;
270 Sensitive *sensitive;
271 char *oktypes, *ktypes;
272 const char *active_ktype;
273 /* kbd-interactive */
280 char *name; /* string to compare against server's list */
281 int (*userauth)(Authctxt *authctxt);
282 void (*cleanup)(Authctxt *authctxt);
283 int *enabled; /* flag in option struct that enables method */
284 int *batch_flag; /* flag in option struct that disables method */
287 int input_userauth_success(int, u_int32_t, void *);
288 int input_userauth_success_unexpected(int, u_int32_t, void *);
289 int input_userauth_failure(int, u_int32_t, void *);
290 int input_userauth_banner(int, u_int32_t, void *);
291 int input_userauth_error(int, u_int32_t, void *);
292 int input_userauth_info_req(int, u_int32_t, void *);
293 int input_userauth_pk_ok(int, u_int32_t, void *);
294 int input_userauth_passwd_changereq(int, u_int32_t, void *);
296 int userauth_none(Authctxt *);
297 int userauth_pubkey(Authctxt *);
298 int userauth_passwd(Authctxt *);
299 int userauth_kbdint(Authctxt *);
300 int userauth_hostbased(Authctxt *);
303 int userauth_gssapi(Authctxt *authctxt);
304 int input_gssapi_response(int type, u_int32_t, void *);
305 int input_gssapi_token(int type, u_int32_t, void *);
306 int input_gssapi_hash(int type, u_int32_t, void *);
307 int input_gssapi_error(int, u_int32_t, void *);
308 int input_gssapi_errtok(int, u_int32_t, void *);
311 void userauth(Authctxt *, char *);
313 static int sign_and_send_pubkey(Authctxt *, Identity *);
314 static void pubkey_prepare(Authctxt *);
315 static void pubkey_cleanup(Authctxt *);
316 static Key *load_identity_file(char *, int);
318 static Authmethod *authmethod_get(char *authlist);
319 static Authmethod *authmethod_lookup(const char *name);
320 static char *authmethods_get(void);
322 Authmethod authmethods[] = {
327 &options.gss_authentication,
333 &options.hostbased_authentication,
338 &options.pubkey_authentication,
340 {"keyboard-interactive",
343 &options.kbd_interactive_authentication,
344 &options.batch_mode},
348 &options.password_authentication,
349 &options.batch_mode},
355 {NULL, NULL, NULL, NULL, NULL}
359 ssh_userauth2(const char *local_user, const char *server_user, char *host,
360 Sensitive *sensitive)
365 if (options.challenge_response_authentication)
366 options.kbd_interactive_authentication = 1;
368 packet_start(SSH2_MSG_SERVICE_REQUEST);
369 packet_put_cstring("ssh-userauth");
371 debug("SSH2_MSG_SERVICE_REQUEST sent");
373 type = packet_read();
374 if (type != SSH2_MSG_SERVICE_ACCEPT)
375 fatal("Server denied authentication request: %d", type);
376 if (packet_remaining() > 0) {
377 char *reply = packet_get_string(NULL);
378 debug2("service_accept: %s", reply);
381 debug2("buggy server: service_accept w/o service");
384 debug("SSH2_MSG_SERVICE_ACCEPT received");
386 if (options.preferred_authentications == NULL)
387 options.preferred_authentications = authmethods_get();
389 /* setup authentication context */
390 memset(&authctxt, 0, sizeof(authctxt));
391 pubkey_prepare(&authctxt);
392 authctxt.server_user = server_user;
393 authctxt.local_user = local_user;
394 authctxt.host = host;
395 authctxt.service = "ssh-connection"; /* service name */
396 authctxt.success = 0;
397 authctxt.method = authmethod_lookup("none");
398 authctxt.authlist = NULL;
399 authctxt.methoddata = NULL;
400 authctxt.sensitive = sensitive;
401 authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
402 authctxt.info_req_seen = 0;
403 authctxt.agent_fd = -1;
404 if (authctxt.method == NULL)
405 fatal("ssh_userauth2: internal error: cannot send userauth none request");
407 /* initial userauth request */
408 userauth_none(&authctxt);
410 dispatch_init(&input_userauth_error);
411 dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
412 dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
413 dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
414 dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
416 pubkey_cleanup(&authctxt);
417 dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
419 debug("Authentication succeeded (%s).", authctxt.method->name);
423 userauth(Authctxt *authctxt, char *authlist)
425 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
426 authctxt->method->cleanup(authctxt);
428 free(authctxt->methoddata);
429 authctxt->methoddata = NULL;
430 if (authlist == NULL) {
431 authlist = authctxt->authlist;
433 free(authctxt->authlist);
434 authctxt->authlist = authlist;
437 Authmethod *method = authmethod_get(authlist);
439 fatal("Permission denied (%s).", authlist);
440 authctxt->method = method;
442 /* reset the per method handler */
443 dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
444 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
446 /* and try new method */
447 if (method->userauth(authctxt) != 0) {
448 debug2("we sent a %s packet, wait for reply", method->name);
451 debug2("we did not send a packet, disable method");
452 method->enabled = NULL;
459 input_userauth_error(int type, u_int32_t seq, void *ctxt)
461 fatal("input_userauth_error: bad message during authentication: "
468 input_userauth_banner(int type, u_int32_t seq, void *ctxt)
470 char *msg, *raw, *lang;
473 debug3("input_userauth_banner");
474 raw = packet_get_string(&len);
475 lang = packet_get_string(NULL);
476 if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
479 msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
480 strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH);
481 fprintf(stderr, "%s", msg);
491 input_userauth_success(int type, u_int32_t seq, void *ctxt)
493 Authctxt *authctxt = ctxt;
495 if (authctxt == NULL)
496 fatal("input_userauth_success: no authentication context");
497 free(authctxt->authlist);
498 authctxt->authlist = NULL;
499 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
500 authctxt->method->cleanup(authctxt);
501 free(authctxt->methoddata);
502 authctxt->methoddata = NULL;
503 authctxt->success = 1; /* break out */
508 input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
510 Authctxt *authctxt = ctxt;
512 if (authctxt == NULL)
513 fatal("%s: no authentication context", __func__);
515 fatal("Unexpected authentication success during %s.",
516 authctxt->method->name);
522 input_userauth_failure(int type, u_int32_t seq, void *ctxt)
524 Authctxt *authctxt = ctxt;
525 char *authlist = NULL;
528 if (authctxt == NULL)
529 fatal("input_userauth_failure: no authentication context");
531 authlist = packet_get_string(NULL);
532 partial = packet_get_char();
536 logit("Authenticated with partial success.");
538 pubkey_cleanup(authctxt);
539 pubkey_prepare(authctxt);
541 debug("Authentications that can continue: %s", authlist);
543 userauth(authctxt, authlist);
549 input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
551 Authctxt *authctxt = ctxt;
555 int pktype, sent = 0;
560 if (authctxt == NULL)
561 fatal("input_userauth_pk_ok: no authentication context");
562 if (datafellows & SSH_BUG_PKOK) {
563 /* this is similar to SSH_BUG_PKAUTH */
564 debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
565 pkblob = packet_get_string(&blen);
567 buffer_append(&b, pkblob, blen);
568 pkalg = buffer_get_string(&b, &alen);
571 pkalg = packet_get_string(&alen);
572 pkblob = packet_get_string(&blen);
576 debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
578 if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
579 debug("unknown pkalg %s", pkalg);
582 if ((key = key_from_blob(pkblob, blen)) == NULL) {
583 debug("no key from blob. pkalg %s", pkalg);
586 if (key->type != pktype) {
587 error("input_userauth_pk_ok: type mismatch "
588 "for decoded key (received %d, expected %d)",
592 if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
593 SSH_FP_DEFAULT)) == NULL)
595 debug2("input_userauth_pk_ok: fp %s", fp);
599 * search keys in the reverse order, because last candidate has been
600 * moved to the end of the queue. this also avoids confusion by
603 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
604 if (key_equal(key, id->key)) {
605 sent = sign_and_send_pubkey(authctxt, id);
615 /* try another method if we did not send a packet */
617 userauth(authctxt, NULL);
623 userauth_gssapi(Authctxt *authctxt)
625 Gssctxt *gssctxt = NULL;
626 static gss_OID_set gss_supported = NULL;
627 static u_int mech = 0;
631 /* Try one GSSAPI method at a time, rather than sending them all at
634 if (gss_supported == NULL)
635 gss_indicate_mechs(&min, &gss_supported);
637 /* Check to see if the mechanism is usable before we offer it */
638 while (mech < gss_supported->count && !ok) {
639 /* My DER encoding requires length<128 */
640 if (gss_supported->elements[mech].length < 128 &&
641 ssh_gssapi_check_mechanism(&gssctxt,
642 &gss_supported->elements[mech], authctxt->host)) {
643 ok = 1; /* Mechanism works */
652 authctxt->methoddata=(void *)gssctxt;
654 packet_start(SSH2_MSG_USERAUTH_REQUEST);
655 packet_put_cstring(authctxt->server_user);
656 packet_put_cstring(authctxt->service);
657 packet_put_cstring(authctxt->method->name);
661 packet_put_int((gss_supported->elements[mech].length) + 2);
662 packet_put_char(SSH_GSS_OIDTYPE);
663 packet_put_char(gss_supported->elements[mech].length);
664 packet_put_raw(gss_supported->elements[mech].elements,
665 gss_supported->elements[mech].length);
669 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
670 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
671 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
672 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
674 mech++; /* Move along to next candidate */
680 process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
682 Authctxt *authctxt = ctxt;
683 Gssctxt *gssctxt = authctxt->methoddata;
684 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
685 gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
686 gss_buffer_desc gssbuf;
687 OM_uint32 status, ms, flags;
690 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
691 recv_tok, &send_tok, &flags);
693 if (send_tok.length > 0) {
694 if (GSS_ERROR(status))
695 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
697 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
699 packet_put_string(send_tok.value, send_tok.length);
701 gss_release_buffer(&ms, &send_tok);
704 if (status == GSS_S_COMPLETE) {
705 /* send either complete or MIC, depending on mechanism */
706 if (!(flags & GSS_C_INTEG_FLAG)) {
707 packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
710 ssh_gssapi_buildmic(&b, authctxt->server_user,
711 authctxt->service, "gssapi-with-mic");
713 gssbuf.value = buffer_ptr(&b);
714 gssbuf.length = buffer_len(&b);
716 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
718 if (!GSS_ERROR(status)) {
719 packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
720 packet_put_string(mic.value, mic.length);
726 gss_release_buffer(&ms, &mic);
735 input_gssapi_response(int type, u_int32_t plen, void *ctxt)
737 Authctxt *authctxt = ctxt;
742 if (authctxt == NULL)
743 fatal("input_gssapi_response: no authentication context");
744 gssctxt = authctxt->methoddata;
747 oidv = packet_get_string(&oidlen);
750 oidv[0] != SSH_GSS_OIDTYPE ||
751 oidv[1] != oidlen - 2) {
753 debug("Badly encoded mechanism OID received");
754 userauth(authctxt, NULL);
758 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
759 fatal("Server returned different OID than expected");
765 if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
766 /* Start again with next method on list */
767 debug("Trying to start again");
768 userauth(authctxt, NULL);
776 input_gssapi_token(int type, u_int32_t plen, void *ctxt)
778 Authctxt *authctxt = ctxt;
779 gss_buffer_desc recv_tok;
783 if (authctxt == NULL)
784 fatal("input_gssapi_response: no authentication context");
786 recv_tok.value = packet_get_string(&slen);
787 recv_tok.length = slen; /* safe typecast */
791 status = process_gssapi_token(ctxt, &recv_tok);
793 free(recv_tok.value);
795 if (GSS_ERROR(status)) {
796 /* Start again with the next method in the list */
797 userauth(authctxt, NULL);
805 input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
807 Authctxt *authctxt = ctxt;
809 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
810 gss_buffer_desc recv_tok;
814 if (authctxt == NULL)
815 fatal("input_gssapi_response: no authentication context");
816 gssctxt = authctxt->methoddata;
818 recv_tok.value = packet_get_string(&len);
819 recv_tok.length = len;
823 /* Stick it into GSSAPI and see what it says */
824 (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
825 &recv_tok, &send_tok, NULL);
827 free(recv_tok.value);
828 gss_release_buffer(&ms, &send_tok);
830 /* Server will be returning a failed packet after this one */
836 input_gssapi_error(int type, u_int32_t plen, void *ctxt)
841 /* maj */(void)packet_get_int();
842 /* min */(void)packet_get_int();
843 msg=packet_get_string(NULL);
844 lang=packet_get_string(NULL);
848 debug("Server GSSAPI Error:\n%s", msg);
856 userauth_none(Authctxt *authctxt)
858 /* initial userauth request */
859 packet_start(SSH2_MSG_USERAUTH_REQUEST);
860 packet_put_cstring(authctxt->server_user);
861 packet_put_cstring(authctxt->service);
862 packet_put_cstring(authctxt->method->name);
868 userauth_passwd(Authctxt *authctxt)
870 static int attempt = 0;
873 const char *host = options.host_key_alias ? options.host_key_alias :
876 if (attempt++ >= options.number_of_password_prompts)
880 error("Permission denied, please try again.");
882 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
883 authctxt->server_user, host);
884 password = read_passphrase(prompt, 0);
885 packet_start(SSH2_MSG_USERAUTH_REQUEST);
886 packet_put_cstring(authctxt->server_user);
887 packet_put_cstring(authctxt->service);
888 packet_put_cstring(authctxt->method->name);
890 packet_put_cstring(password);
891 explicit_bzero(password, strlen(password));
893 packet_add_padding(64);
896 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
897 &input_userauth_passwd_changereq);
903 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
907 input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
909 Authctxt *authctxt = ctxt;
910 char *info, *lang, *password = NULL, *retype = NULL;
912 const char *host = options.host_key_alias ? options.host_key_alias :
915 debug2("input_userauth_passwd_changereq");
917 if (authctxt == NULL)
918 fatal("input_userauth_passwd_changereq: "
919 "no authentication context");
921 info = packet_get_string(NULL);
922 lang = packet_get_string(NULL);
923 if (strlen(info) > 0)
927 packet_start(SSH2_MSG_USERAUTH_REQUEST);
928 packet_put_cstring(authctxt->server_user);
929 packet_put_cstring(authctxt->service);
930 packet_put_cstring(authctxt->method->name);
931 packet_put_char(1); /* additional info */
932 snprintf(prompt, sizeof(prompt),
933 "Enter %.30s@%.128s's old password: ",
934 authctxt->server_user, host);
935 password = read_passphrase(prompt, 0);
936 packet_put_cstring(password);
937 explicit_bzero(password, strlen(password));
940 while (password == NULL) {
941 snprintf(prompt, sizeof(prompt),
942 "Enter %.30s@%.128s's new password: ",
943 authctxt->server_user, host);
944 password = read_passphrase(prompt, RP_ALLOW_EOF);
945 if (password == NULL) {
949 snprintf(prompt, sizeof(prompt),
950 "Retype %.30s@%.128s's new password: ",
951 authctxt->server_user, host);
952 retype = read_passphrase(prompt, 0);
953 if (strcmp(password, retype) != 0) {
954 explicit_bzero(password, strlen(password));
956 logit("Mismatch; try again, EOF to quit.");
959 explicit_bzero(retype, strlen(retype));
962 packet_put_cstring(password);
963 explicit_bzero(password, strlen(password));
965 packet_add_padding(64);
968 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
969 &input_userauth_passwd_changereq);
974 identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
975 const u_char *data, size_t datalen, u_int compat)
980 /* the agent supports this key */
982 return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
983 data, datalen, compat);
986 * we have already loaded the private key or
987 * the private key is stored in external hardware
989 if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))
990 return (sshkey_sign(id->key, sigp, lenp, data, datalen,
992 /* load the private key from the file */
993 if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
994 return (-1); /* XXX return decent error code */
995 ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat);
1001 sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1004 u_char *blob, *signature;
1012 if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1013 SSH_FP_DEFAULT)) == NULL)
1015 debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1018 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1019 /* we cannot handle this key */
1020 debug3("sign_and_send_pubkey: cannot handle key");
1023 /* data to be signed */
1025 if (datafellows & SSH_OLD_SESSIONID) {
1026 buffer_append(&b, session_id2, session_id2_len);
1027 skip = session_id2_len;
1029 buffer_put_string(&b, session_id2, session_id2_len);
1030 skip = buffer_len(&b);
1032 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1033 buffer_put_cstring(&b, authctxt->server_user);
1034 buffer_put_cstring(&b,
1035 datafellows & SSH_BUG_PKSERVICE ?
1038 if (datafellows & SSH_BUG_PKAUTH) {
1039 buffer_put_char(&b, have_sig);
1041 buffer_put_cstring(&b, authctxt->method->name);
1042 buffer_put_char(&b, have_sig);
1043 buffer_put_cstring(&b, key_ssh_name(id->key));
1045 buffer_put_string(&b, blob, bloblen);
1047 /* generate signature */
1048 ret = identity_sign(id, &signature, &slen,
1049 buffer_ptr(&b), buffer_len(&b), datafellows);
1058 if (datafellows & SSH_BUG_PKSERVICE) {
1060 buffer_append(&b, session_id2, session_id2_len);
1061 skip = session_id2_len;
1062 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1063 buffer_put_cstring(&b, authctxt->server_user);
1064 buffer_put_cstring(&b, authctxt->service);
1065 buffer_put_cstring(&b, authctxt->method->name);
1066 buffer_put_char(&b, have_sig);
1067 if (!(datafellows & SSH_BUG_PKAUTH))
1068 buffer_put_cstring(&b, key_ssh_name(id->key));
1069 buffer_put_string(&b, blob, bloblen);
1073 /* append signature */
1074 buffer_put_string(&b, signature, slen);
1077 /* skip session id and packet type */
1078 if (buffer_len(&b) < skip + 1)
1079 fatal("userauth_pubkey: internal error");
1080 buffer_consume(&b, skip + 1);
1082 /* put remaining data from buffer into packet */
1083 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1084 packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1092 send_pubkey_test(Authctxt *authctxt, Identity *id)
1095 u_int bloblen, have_sig = 0;
1097 debug3("send_pubkey_test");
1099 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1100 /* we cannot handle this key */
1101 debug3("send_pubkey_test: cannot handle key");
1104 /* register callback for USERAUTH_PK_OK message */
1105 dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1107 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1108 packet_put_cstring(authctxt->server_user);
1109 packet_put_cstring(authctxt->service);
1110 packet_put_cstring(authctxt->method->name);
1111 packet_put_char(have_sig);
1112 if (!(datafellows & SSH_BUG_PKAUTH))
1113 packet_put_cstring(key_ssh_name(id->key));
1114 packet_put_string(blob, bloblen);
1121 load_identity_file(char *filename, int userprovided)
1124 char prompt[300], *passphrase;
1125 int r, perm_ok = 0, quit = 0, i;
1128 if (stat(filename, &st) < 0) {
1129 (userprovided ? logit : debug3)("no such identity: %s: %s",
1130 filename, strerror(errno));
1133 snprintf(prompt, sizeof prompt,
1134 "Enter passphrase for key '%.100s': ", filename);
1135 for (i = 0; i <= options.number_of_password_prompts; i++) {
1139 passphrase = read_passphrase(prompt, 0);
1140 if (*passphrase == '\0') {
1141 debug2("no passphrase given, try next key");
1146 switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename,
1147 passphrase, &private, NULL, &perm_ok))) {
1150 case SSH_ERR_KEY_WRONG_PASSPHRASE:
1151 if (options.batch_mode) {
1156 debug2("bad passphrase given, try again...");
1158 case SSH_ERR_SYSTEM_ERROR:
1159 if (errno == ENOENT) {
1160 debug2("Load key \"%s\": %s",
1161 filename, ssh_err(r));
1167 error("Load key \"%s\": %s", filename, ssh_err(r));
1172 explicit_bzero(passphrase, strlen(passphrase));
1175 if (private != NULL || quit)
1182 * try keys in the following order:
1183 * 1. agent keys that are found in the config file
1184 * 2. other agent keys
1185 * 3. keys that are only listed in the config file
1188 pubkey_prepare(Authctxt *authctxt)
1190 struct identity *id, *id2, *tmp;
1191 struct idlist agent, files, *preferred;
1193 int agent_fd, i, r, found;
1195 struct ssh_identitylist *idlist;
1197 TAILQ_INIT(&agent); /* keys from the agent */
1198 TAILQ_INIT(&files); /* keys from the config file */
1199 preferred = &authctxt->keys;
1200 TAILQ_INIT(preferred); /* preferred order of keys */
1202 /* list of keys stored in the filesystem and PKCS#11 */
1203 for (i = 0; i < options.num_identity_files; i++) {
1204 key = options.identity_keys[i];
1205 if (key && key->type == KEY_RSA1)
1207 if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1209 options.identity_keys[i] = NULL;
1210 id = xcalloc(1, sizeof(*id));
1212 id->filename = xstrdup(options.identity_files[i]);
1213 id->userprovided = options.identity_file_userprovided[i];
1214 TAILQ_INSERT_TAIL(&files, id, next);
1216 /* Prefer PKCS11 keys that are explicitly listed */
1217 TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1218 if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1221 TAILQ_FOREACH(id2, &files, next) {
1222 if (id2->key == NULL ||
1223 (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1225 if (sshkey_equal(id->key, id2->key)) {
1226 TAILQ_REMOVE(&files, id, next);
1227 TAILQ_INSERT_TAIL(preferred, id, next);
1232 /* If IdentitiesOnly set and key not found then don't use it */
1233 if (!found && options.identities_only) {
1234 TAILQ_REMOVE(&files, id, next);
1235 explicit_bzero(id, sizeof(*id));
1239 /* list of keys supported by the agent */
1240 if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1241 if (r != SSH_ERR_AGENT_NOT_PRESENT)
1242 debug("%s: ssh_get_authentication_socket: %s",
1243 __func__, ssh_err(r));
1244 } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) {
1245 if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1246 debug("%s: ssh_fetch_identitylist: %s",
1247 __func__, ssh_err(r));
1249 for (j = 0; j < idlist->nkeys; j++) {
1251 TAILQ_FOREACH(id, &files, next) {
1253 * agent keys from the config file are
1256 if (sshkey_equal(idlist->keys[j], id->key)) {
1257 TAILQ_REMOVE(&files, id, next);
1258 TAILQ_INSERT_TAIL(preferred, id, next);
1259 id->agent_fd = agent_fd;
1264 if (!found && !options.identities_only) {
1265 id = xcalloc(1, sizeof(*id));
1266 /* XXX "steals" key/comment from idlist */
1267 id->key = idlist->keys[j];
1268 id->filename = idlist->comments[j];
1269 idlist->keys[j] = NULL;
1270 idlist->comments[j] = NULL;
1271 id->agent_fd = agent_fd;
1272 TAILQ_INSERT_TAIL(&agent, id, next);
1275 ssh_free_identitylist(idlist);
1276 /* append remaining agent keys */
1277 for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1278 TAILQ_REMOVE(&agent, id, next);
1279 TAILQ_INSERT_TAIL(preferred, id, next);
1281 authctxt->agent_fd = agent_fd;
1283 /* append remaining keys from the config file */
1284 for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1285 TAILQ_REMOVE(&files, id, next);
1286 TAILQ_INSERT_TAIL(preferred, id, next);
1288 TAILQ_FOREACH(id, preferred, next) {
1289 debug2("key: %s (%p),%s", id->filename, id->key,
1290 id->userprovided ? " explicit" : "");
1295 pubkey_cleanup(Authctxt *authctxt)
1299 if (authctxt->agent_fd != -1)
1300 ssh_close_authentication_socket(authctxt->agent_fd);
1301 for (id = TAILQ_FIRST(&authctxt->keys); id;
1302 id = TAILQ_FIRST(&authctxt->keys)) {
1303 TAILQ_REMOVE(&authctxt->keys, id, next);
1305 sshkey_free(id->key);
1312 try_identity(Identity *id)
1316 if (match_pattern_list(sshkey_ssh_name(id->key),
1317 options.pubkey_key_types, 0) != 1) {
1318 debug("Skipping %s key %s for not in PubkeyAcceptedKeyTypes",
1319 sshkey_ssh_name(id->key), id->filename);
1322 if (key_type_plain(id->key->type) == KEY_RSA &&
1323 (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1324 debug("Skipped %s key %s for RSA/MD5 server",
1325 key_type(id->key), id->filename);
1328 return (id->key->type != KEY_RSA1);
1332 userauth_pubkey(Authctxt *authctxt)
1337 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1340 /* move key to the end of the queue */
1341 TAILQ_REMOVE(&authctxt->keys, id, next);
1342 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1344 * send a test message if we have the public key. for
1345 * encrypted keys we cannot do this and have to load the
1346 * private key instead
1348 if (id->key != NULL) {
1349 if (try_identity(id)) {
1350 debug("Offering %s public key: %s",
1351 key_type(id->key), id->filename);
1352 sent = send_pubkey_test(authctxt, id);
1355 debug("Trying private key: %s", id->filename);
1356 id->key = load_identity_file(id->filename,
1358 if (id->key != NULL) {
1359 if (try_identity(id)) {
1361 sent = sign_and_send_pubkey(
1375 * Send userauth request message specifying keyboard-interactive method.
1378 userauth_kbdint(Authctxt *authctxt)
1380 static int attempt = 0;
1382 if (attempt++ >= options.number_of_password_prompts)
1384 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1385 if (attempt > 1 && !authctxt->info_req_seen) {
1386 debug3("userauth_kbdint: disable: no info_req_seen");
1387 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1391 debug2("userauth_kbdint");
1392 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1393 packet_put_cstring(authctxt->server_user);
1394 packet_put_cstring(authctxt->service);
1395 packet_put_cstring(authctxt->method->name);
1396 packet_put_cstring(""); /* lang */
1397 packet_put_cstring(options.kbd_interactive_devices ?
1398 options.kbd_interactive_devices : "");
1401 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1406 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1409 input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1411 Authctxt *authctxt = ctxt;
1412 char *name, *inst, *lang, *prompt, *response;
1413 u_int num_prompts, i;
1416 debug2("input_userauth_info_req");
1418 if (authctxt == NULL)
1419 fatal("input_userauth_info_req: no authentication context");
1421 authctxt->info_req_seen = 1;
1423 name = packet_get_string(NULL);
1424 inst = packet_get_string(NULL);
1425 lang = packet_get_string(NULL);
1426 if (strlen(name) > 0)
1428 if (strlen(inst) > 0)
1434 num_prompts = packet_get_int();
1436 * Begin to build info response packet based on prompts requested.
1437 * We commit to providing the correct number of responses, so if
1438 * further on we run into a problem that prevents this, we have to
1439 * be sure and clean this up and send a correct error response.
1441 packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1442 packet_put_int(num_prompts);
1444 debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1445 for (i = 0; i < num_prompts; i++) {
1446 prompt = packet_get_string(NULL);
1447 echo = packet_get_char();
1449 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1451 packet_put_cstring(response);
1452 explicit_bzero(response, strlen(response));
1456 packet_check_eom(); /* done with parsing incoming message. */
1458 packet_add_padding(64);
1464 ssh_keysign(struct sshkey *key, u_char **sigp, size_t *lenp,
1465 const u_char *data, size_t datalen)
1470 int i, r, to[2], from[2], status, sock = packet_get_connection_in();
1471 u_char rversion = 0, version = 2;
1472 void (*osigchld)(int);
1477 if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1478 error("%s: not installed: %s", __func__, strerror(errno));
1481 if (fflush(stdout) != 0) {
1482 error("%s: fflush: %s", __func__, strerror(errno));
1486 error("%s: pipe: %s", __func__, strerror(errno));
1489 if (pipe(from) < 0) {
1490 error("%s: pipe: %s", __func__, strerror(errno));
1493 if ((pid = fork()) < 0) {
1494 error("%s: fork: %s", __func__, strerror(errno));
1497 osigchld = signal(SIGCHLD, SIG_DFL);
1499 /* keep the socket on exec */
1500 fcntl(sock, F_SETFD, 0);
1501 permanently_drop_suid(getuid());
1503 if (dup2(from[1], STDOUT_FILENO) < 0)
1504 fatal("%s: dup2: %s", __func__, strerror(errno));
1506 if (dup2(to[0], STDIN_FILENO) < 0)
1507 fatal("%s: dup2: %s", __func__, strerror(errno));
1510 /* Close everything but stdio and the socket */
1511 for (i = STDERR_FILENO + 1; i < sock; i++)
1513 closefrom(sock + 1);
1514 debug3("%s: [child] pid=%ld, exec %s",
1515 __func__, (long)getpid(), _PATH_SSH_KEY_SIGN);
1516 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1517 fatal("%s: exec(%s): %s", __func__, _PATH_SSH_KEY_SIGN,
1523 if ((b = sshbuf_new()) == NULL)
1524 fatal("%s: sshbuf_new failed", __func__);
1525 /* send # of sock, data to be signed */
1526 if ((r = sshbuf_put_u32(b, sock) != 0) ||
1527 (r = sshbuf_put_string(b, data, datalen)) != 0)
1528 fatal("%s: buffer error: %s", __func__, ssh_err(r));
1529 if (ssh_msg_send(to[1], version, b) == -1)
1530 fatal("%s: couldn't send request", __func__);
1532 r = ssh_msg_recv(from[0], b);
1536 error("%s: no reply", __func__);
1541 while (waitpid(pid, &status, 0) < 0) {
1542 if (errno != EINTR) {
1543 error("%s: waitpid %ld: %s",
1544 __func__, (long)pid, strerror(errno));
1548 if (!WIFEXITED(status)) {
1549 error("%s: exited abnormally", __func__);
1552 if (WEXITSTATUS(status) != 0) {
1553 error("%s: exited with status %d",
1554 __func__, WEXITSTATUS(status));
1557 if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1558 error("%s: buffer error: %s", __func__, ssh_err(r));
1561 if (rversion != version) {
1562 error("%s: bad version", __func__);
1565 if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1566 error("%s: buffer error: %s", __func__, ssh_err(r));
1568 signal(SIGCHLD, osigchld);
1572 signal(SIGCHLD, osigchld);
1579 userauth_hostbased(Authctxt *authctxt)
1581 struct ssh *ssh = active_state;
1582 struct sshkey *private = NULL;
1583 struct sshbuf *b = NULL;
1584 const char *service;
1585 u_char *sig = NULL, *keyblob = NULL;
1586 char *fp = NULL, *chost = NULL, *lname = NULL;
1587 size_t siglen = 0, keylen = 0;
1588 int i, r, success = 0;
1590 if (authctxt->ktypes == NULL) {
1591 authctxt->oktypes = xstrdup(options.hostbased_key_types);
1592 authctxt->ktypes = authctxt->oktypes;
1596 * Work through each listed type pattern in HostbasedKeyTypes,
1597 * trying each hostkey that matches the type in turn.
1600 if (authctxt->active_ktype == NULL)
1601 authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
1602 if (authctxt->active_ktype == NULL ||
1603 *authctxt->active_ktype == '\0')
1605 debug3("%s: trying key type %s", __func__,
1606 authctxt->active_ktype);
1608 /* check for a useful key */
1610 for (i = 0; i < authctxt->sensitive->nkeys; i++) {
1611 if (authctxt->sensitive->keys[i] == NULL ||
1612 authctxt->sensitive->keys[i]->type == KEY_RSA1 ||
1613 authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
1615 if (match_pattern_list(
1616 sshkey_ssh_name(authctxt->sensitive->keys[i]),
1617 authctxt->active_ktype, 0) != 1)
1619 /* we take and free the key */
1620 private = authctxt->sensitive->keys[i];
1621 authctxt->sensitive->keys[i] = NULL;
1625 if (private != NULL)
1627 /* No more keys of this type; advance */
1628 authctxt->active_ktype = NULL;
1630 if (private == NULL) {
1631 free(authctxt->oktypes);
1632 authctxt->oktypes = authctxt->ktypes = NULL;
1633 authctxt->active_ktype = NULL;
1634 debug("No more client hostkeys for hostbased authentication.");
1638 if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
1639 SSH_FP_DEFAULT)) == NULL) {
1640 error("%s: sshkey_fingerprint failed", __func__);
1643 debug("%s: trying hostkey %s %s",
1644 __func__, sshkey_ssh_name(private), fp);
1646 /* figure out a name for the client host */
1647 if ((lname = get_local_name(packet_get_connection_in())) == NULL) {
1648 error("%s: cannot get local ipaddr/name", __func__);
1652 /* XXX sshbuf_put_stringf? */
1653 xasprintf(&chost, "%s.", lname);
1654 debug2("%s: chost %s", __func__, chost);
1656 service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1659 /* construct data */
1660 if ((b = sshbuf_new()) == NULL) {
1661 error("%s: sshbuf_new failed", __func__);
1664 if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1665 error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
1668 if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
1669 (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1670 (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1671 (r = sshbuf_put_cstring(b, service)) != 0 ||
1672 (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1673 (r = sshbuf_put_cstring(b, key_ssh_name(private))) != 0 ||
1674 (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
1675 (r = sshbuf_put_cstring(b, chost)) != 0 ||
1676 (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1677 error("%s: buffer error: %s", __func__, ssh_err(r));
1682 sshbuf_dump(b, stderr);
1684 if (authctxt->sensitive->external_keysign)
1685 r = ssh_keysign(private, &sig, &siglen,
1686 sshbuf_ptr(b), sshbuf_len(b));
1687 else if ((r = sshkey_sign(private, &sig, &siglen,
1688 sshbuf_ptr(b), sshbuf_len(b), datafellows)) != 0)
1689 debug("%s: sshkey_sign: %s", __func__, ssh_err(r));
1691 error("sign using hostkey %s %s failed",
1692 sshkey_ssh_name(private), fp);
1695 if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1696 (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1697 (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1698 (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1699 (r = sshpkt_put_cstring(ssh, key_ssh_name(private))) != 0 ||
1700 (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
1701 (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
1702 (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
1703 (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
1704 (r = sshpkt_send(ssh)) != 0) {
1705 error("%s: packet error: %s", __func__, ssh_err(r));
1712 explicit_bzero(sig, siglen);
1719 sshkey_free(private);
1725 /* find auth method */
1728 * given auth method name, if configurable options permit this method fill
1729 * in auth_ident field and return true, otherwise return false.
1732 authmethod_is_enabled(Authmethod *method)
1736 /* return false if options indicate this method is disabled */
1737 if (method->enabled == NULL || *method->enabled == 0)
1739 /* return false if batch mode is enabled but method needs interactive mode */
1740 if (method->batch_flag != NULL && *method->batch_flag != 0)
1746 authmethod_lookup(const char *name)
1748 Authmethod *method = NULL;
1750 for (method = authmethods; method->name != NULL; method++)
1751 if (strcmp(name, method->name) == 0)
1753 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1757 /* XXX internal state */
1758 static Authmethod *current = NULL;
1759 static char *supported = NULL;
1760 static char *preferred = NULL;
1763 * Given the authentication method list sent by the server, return the
1764 * next method we should try. If the server initially sends a nil list,
1765 * use a built-in default list.
1768 authmethod_get(char *authlist)
1773 /* Use a suitable default if we're passed a nil list. */
1774 if (authlist == NULL || strlen(authlist) == 0)
1775 authlist = options.preferred_authentications;
1777 if (supported == NULL || strcmp(authlist, supported) != 0) {
1778 debug3("start over, passed a different list %s", authlist);
1780 supported = xstrdup(authlist);
1781 preferred = options.preferred_authentications;
1782 debug3("preferred %s", preferred);
1784 } else if (current != NULL && authmethod_is_enabled(current))
1788 if ((name = match_list(preferred, supported, &next)) == NULL) {
1789 debug("No more authentication methods to try.");
1794 debug3("authmethod_lookup %s", name);
1795 debug3("remaining preferred: %s", preferred);
1796 if ((current = authmethod_lookup(name)) != NULL &&
1797 authmethod_is_enabled(current)) {
1798 debug3("authmethod_is_enabled %s", name);
1799 debug("Next authentication method: %s", name);
1808 authmethods_get(void)
1810 Authmethod *method = NULL;
1815 for (method = authmethods; method->name != NULL; method++) {
1816 if (authmethod_is_enabled(method)) {
1817 if (buffer_len(&b) > 0)
1818 buffer_append(&b, ",", 1);
1819 buffer_append(&b, method->name, strlen(method->name));
1822 buffer_append(&b, "\0", 1);
1823 list = xstrdup(buffer_ptr(&b));