1 /* $OpenBSD: sshconnect2.c,v 1.171 2009/03/05 07:18:19 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>
42 #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H)
46 #include "openbsd-compat/sys-queue.h"
57 #include "myproposal.h"
58 #include "sshconnect.h"
69 #include "pathnames.h"
79 extern char *client_version_string;
80 extern char *server_version_string;
81 extern Options options;
84 /* tty_flag is set in ssh.c. use this in ssh_userauth2 */
85 /* if it is set then prevent the switch to the null cipher */
89 /* tty_flag is set in ssh.c. use this in ssh_userauth2 */
90 /* if it is set then prevent the switch to the null cipher */
94 /* tty_flag is set in ssh.c. use this in ssh_userauth2 */
95 /* if it is set then prevent the switch to the null cipher */
103 u_char *session_id2 = NULL;
104 u_int session_id2_len = 0;
107 struct sockaddr *xxx_hostaddr;
112 verify_host_key_callback(Key *hostkey)
114 if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
115 fatal("Host key verification failed.");
120 ssh_kex2(char *host, struct sockaddr *hostaddr)
125 char *orig = NULL, *gss = NULL;
126 char *gss_host = NULL;
130 xxx_hostaddr = hostaddr;
133 if (options.gss_keyex) {
134 /* Add the GSSAPI mechanisms currently supported on this
135 * client to the key exchange algorithm proposal */
136 orig = myproposal[PROPOSAL_KEX_ALGS];
138 if (options.gss_trust_dns)
139 gss_host = (char *)get_canonical_hostname(1);
143 gss = ssh_gssapi_client_mechanisms(gss_host, options.gss_client_identity);
145 debug("Offering GSSAPI proposal: %s", gss);
146 xasprintf(&myproposal[PROPOSAL_KEX_ALGS],
152 if (options.ciphers == (char *)-1) {
153 logit("No valid ciphers for protocol version 2 given, using defaults.");
154 options.ciphers = NULL;
156 if (options.ciphers != NULL) {
157 myproposal[PROPOSAL_ENC_ALGS_CTOS] =
158 myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
160 myproposal[PROPOSAL_ENC_ALGS_CTOS] =
161 compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
162 myproposal[PROPOSAL_ENC_ALGS_STOC] =
163 compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
164 if (options.compression) {
165 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
166 myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
168 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
169 myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
171 if (options.macs != NULL) {
172 myproposal[PROPOSAL_MAC_ALGS_CTOS] =
173 myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
175 if (options.hostkeyalgorithms != NULL)
176 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
177 options.hostkeyalgorithms;
180 /* If we've got GSSAPI algorithms, then we also support the
181 * 'null' hostkey, as a last resort */
182 if (options.gss_keyex && gss) {
183 orig = myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS];
184 xasprintf(&myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS],
190 if (options.rekey_limit)
191 packet_set_rekey_limit((u_int32_t)options.rekey_limit);
193 /* start key exchange */
194 kex = kex_setup(myproposal);
195 kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
196 kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
197 kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
198 kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
200 if (options.gss_keyex) {
201 kex->kex[KEX_GSS_GRP1_SHA1] = kexgss_client;
202 kex->kex[KEX_GSS_GRP14_SHA1] = kexgss_client;
203 kex->kex[KEX_GSS_GEX_SHA1] = kexgss_client;
206 kex->client_version_string=client_version_string;
207 kex->server_version_string=server_version_string;
208 kex->verify_host_key=&verify_host_key_callback;
211 if (options.gss_keyex) {
212 kex->gss_deleg_creds = options.gss_deleg_creds;
213 kex->gss_trust_dns = options.gss_trust_dns;
214 kex->gss_client = options.gss_client_identity;
215 kex->gss_host = gss_host;
221 dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
223 session_id2 = kex->session_id;
224 session_id2_len = kex->session_id_len;
227 /* send 1st encrypted/maced/compressed message */
228 packet_start(SSH2_MSG_IGNORE);
229 packet_put_cstring("markus");
239 typedef struct Authctxt Authctxt;
240 typedef struct Authmethod Authmethod;
241 typedef struct identity Identity;
242 typedef struct idlist Idlist;
245 TAILQ_ENTRY(identity) next;
246 AuthenticationConnection *ac; /* set if agent supports key */
247 Key *key; /* public/private key */
248 char *filename; /* comment for agent-only keys */
250 int isprivate; /* key points to the private key */
252 TAILQ_HEAD(idlist, identity);
255 const char *server_user;
256 const char *local_user;
264 AuthenticationConnection *agent;
266 Sensitive *sensitive;
267 /* kbd-interactive */
273 char *name; /* string to compare against server's list */
274 int (*userauth)(Authctxt *authctxt);
275 void (*cleanup)(Authctxt *authctxt);
276 int *enabled; /* flag in option struct that enables method */
277 int *batch_flag; /* flag in option struct that disables method */
280 void input_userauth_success(int, u_int32_t, void *);
281 void input_userauth_failure(int, u_int32_t, void *);
282 void input_userauth_banner(int, u_int32_t, void *);
283 void input_userauth_error(int, u_int32_t, void *);
284 void input_userauth_info_req(int, u_int32_t, void *);
285 void input_userauth_pk_ok(int, u_int32_t, void *);
286 void input_userauth_passwd_changereq(int, u_int32_t, void *);
287 void input_userauth_jpake_server_step1(int, u_int32_t, void *);
288 void input_userauth_jpake_server_step2(int, u_int32_t, void *);
289 void input_userauth_jpake_server_confirm(int, u_int32_t, void *);
291 int userauth_none(Authctxt *);
292 int userauth_pubkey(Authctxt *);
293 int userauth_passwd(Authctxt *);
294 int userauth_kbdint(Authctxt *);
295 int userauth_hostbased(Authctxt *);
296 int userauth_jpake(Authctxt *);
298 void userauth_jpake_cleanup(Authctxt *);
301 int userauth_external(Authctxt *authctxt);
302 int userauth_gssapi(Authctxt *authctxt);
303 int userauth_gssapi_with_mic(Authctxt *authctxt);
304 int userauth_gssapi_without_mic(Authctxt *authctxt);
305 void input_gssapi_response(int type, u_int32_t, void *);
306 void input_gssapi_token(int type, u_int32_t, void *);
307 void input_gssapi_hash(int type, u_int32_t, void *);
308 void input_gssapi_error(int, u_int32_t, void *);
309 void input_gssapi_errtok(int, u_int32_t, void *);
310 int userauth_gsskeyex(Authctxt *authctxt);
313 void userauth(Authctxt *, char *);
315 static int sign_and_send_pubkey(Authctxt *, Identity *);
316 static void pubkey_prepare(Authctxt *);
317 static void pubkey_cleanup(Authctxt *);
318 static Key *load_identity_file(char *);
320 static Authmethod *authmethod_get(char *authlist);
321 static Authmethod *authmethod_lookup(const char *name);
322 static char *authmethods_get(void);
324 Authmethod authmethods[] = {
329 &options.gss_authentication,
334 &options.gss_authentication,
339 &options.gss_authentication,
344 &options.gss_authentication,
350 &options.hostbased_authentication,
355 &options.pubkey_authentication,
358 {"jpake-01@openssh.com",
360 userauth_jpake_cleanup,
361 &options.zero_knowledge_password_authentication,
362 &options.batch_mode},
364 {"keyboard-interactive",
367 &options.kbd_interactive_authentication,
368 &options.batch_mode},
372 &options.password_authentication,
373 &options.batch_mode},
379 {NULL, NULL, NULL, NULL, NULL}
383 ssh_userauth2(const char *local_user, const char *server_user, char *host,
384 Sensitive *sensitive)
389 if (options.challenge_response_authentication)
390 options.kbd_interactive_authentication = 1;
392 packet_start(SSH2_MSG_SERVICE_REQUEST);
393 packet_put_cstring("ssh-userauth");
395 debug("SSH2_MSG_SERVICE_REQUEST sent");
397 type = packet_read();
398 if (type != SSH2_MSG_SERVICE_ACCEPT)
399 fatal("Server denied authentication request: %d", type);
400 if (packet_remaining() > 0) {
401 char *reply = packet_get_string(NULL);
402 debug2("service_accept: %s", reply);
405 debug2("buggy server: service_accept w/o service");
408 debug("SSH2_MSG_SERVICE_ACCEPT received");
410 if (options.preferred_authentications == NULL)
411 options.preferred_authentications = authmethods_get();
413 /* setup authentication context */
414 memset(&authctxt, 0, sizeof(authctxt));
415 pubkey_prepare(&authctxt);
416 authctxt.server_user = server_user;
417 authctxt.local_user = local_user;
418 authctxt.host = host;
419 authctxt.service = "ssh-connection"; /* service name */
420 authctxt.success = 0;
421 authctxt.method = authmethod_lookup("none");
422 authctxt.authlist = NULL;
423 authctxt.methoddata = NULL;
424 authctxt.sensitive = sensitive;
425 authctxt.info_req_seen = 0;
426 if (authctxt.method == NULL)
427 fatal("ssh_userauth2: internal error: cannot send userauth none request");
429 /* initial userauth request */
430 userauth_none(&authctxt);
432 dispatch_init(&input_userauth_error);
433 dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
434 dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
435 dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
436 dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
438 pubkey_cleanup(&authctxt);
439 dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
441 /* if the user wants to use the none cipher do it */
442 /* post authentication and only if the right conditions are met */
443 /* both of the NONE commands must be true and there must be no */
445 if ((options.none_switch == 1) && (options.none_enabled == 1))
447 if (!tty_flag) /* no null on tty sessions */
449 debug("Requesting none rekeying...");
450 myproposal[PROPOSAL_ENC_ALGS_STOC] = "none";
451 myproposal[PROPOSAL_ENC_ALGS_CTOS] = "none";
452 kex_prop2buf(&xxx_kex->my,myproposal);
453 packet_request_rekeying();
454 fprintf(stderr, "WARNING: ENABLED NONE CIPHER\n");
458 /* requested NONE cipher when in a tty */
459 debug("Cannot switch to NONE cipher with tty allocated");
460 fprintf(stderr, "NONE cipher switch disabled when a TTY is allocated\n");
463 debug("Authentication succeeded (%s).", authctxt.method->name);
467 userauth(Authctxt *authctxt, char *authlist)
469 if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
470 authctxt->method->cleanup(authctxt);
472 if (authctxt->methoddata) {
473 xfree(authctxt->methoddata);
474 authctxt->methoddata = NULL;
476 if (authlist == NULL) {
477 authlist = authctxt->authlist;
479 if (authctxt->authlist)
480 xfree(authctxt->authlist);
481 authctxt->authlist = authlist;
484 Authmethod *method = authmethod_get(authlist);
486 fatal("Permission denied (%s).", authlist);
487 authctxt->method = method;
489 /* reset the per method handler */
490 dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
491 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
493 /* and try new method */
494 if (method->userauth(authctxt) != 0) {
495 debug2("we sent a %s packet, wait for reply", method->name);
498 debug2("we did not send a packet, disable method");
499 method->enabled = NULL;
506 input_userauth_error(int type, u_int32_t seq, void *ctxt)
508 fatal("input_userauth_error: bad message during authentication: "
514 input_userauth_banner(int type, u_int32_t seq, void *ctxt)
516 char *msg, *raw, *lang;
519 debug3("input_userauth_banner");
520 raw = packet_get_string(&len);
521 lang = packet_get_string(NULL);
522 if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
525 msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
526 strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL);
527 fprintf(stderr, "%s", msg);
536 input_userauth_success(int type, u_int32_t seq, void *ctxt)
538 Authctxt *authctxt = ctxt;
539 if (authctxt == NULL)
540 fatal("input_userauth_success: no authentication context");
541 if (authctxt->authlist) {
542 xfree(authctxt->authlist);
543 authctxt->authlist = NULL;
545 if (authctxt->methoddata) {
546 xfree(authctxt->methoddata);
547 authctxt->methoddata = NULL;
549 authctxt->success = 1; /* break out */
554 input_userauth_failure(int type, u_int32_t seq, void *ctxt)
556 Authctxt *authctxt = ctxt;
557 char *authlist = NULL;
560 if (authctxt == NULL)
561 fatal("input_userauth_failure: no authentication context");
563 authlist = packet_get_string(NULL);
564 partial = packet_get_char();
568 logit("Authenticated with partial success.");
569 debug("Authentications that can continue: %s", authlist);
571 userauth(authctxt, authlist);
576 input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
578 Authctxt *authctxt = ctxt;
582 int pktype, sent = 0;
587 if (authctxt == NULL)
588 fatal("input_userauth_pk_ok: no authentication context");
589 if (datafellows & SSH_BUG_PKOK) {
590 /* this is similar to SSH_BUG_PKAUTH */
591 debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
592 pkblob = packet_get_string(&blen);
594 buffer_append(&b, pkblob, blen);
595 pkalg = buffer_get_string(&b, &alen);
598 pkalg = packet_get_string(&alen);
599 pkblob = packet_get_string(&blen);
603 debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
605 if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
606 debug("unknown pkalg %s", pkalg);
609 if ((key = key_from_blob(pkblob, blen)) == NULL) {
610 debug("no key from blob. pkalg %s", pkalg);
613 if (key->type != pktype) {
614 error("input_userauth_pk_ok: type mismatch "
615 "for decoded key (received %d, expected %d)",
619 fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
620 debug2("input_userauth_pk_ok: fp %s", fp);
624 * search keys in the reverse order, because last candidate has been
625 * moved to the end of the queue. this also avoids confusion by
628 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
629 if (key_equal(key, id->key)) {
630 sent = sign_and_send_pubkey(authctxt, id);
640 /* try another method if we did not send a packet */
642 userauth(authctxt, NULL);
647 userauth_gssapi(Authctxt *authctxt)
649 Gssctxt *gssctxt = NULL;
650 static gss_OID_set gss_supported = NULL;
651 static u_int mech = 0;
654 char *gss_host = NULL;
656 if (!options.gss_authentication) {
657 verbose("GSSAPI authentication disabled.");
661 if (options.gss_trust_dns)
662 gss_host = (char *)get_canonical_hostname(1);
664 gss_host = (char *)authctxt->host;
666 /* Try one GSSAPI method at a time, rather than sending them all at
669 if (gss_supported == NULL)
670 if (GSS_ERROR(gss_indicate_mechs(&min, &gss_supported))) {
671 gss_supported = NULL;
675 /* Check to see if the mechanism is usable before we offer it */
676 while (mech < gss_supported->count && !ok) {
677 /* My DER encoding requires length<128 */
678 if (gss_supported->elements[mech].length < 128 &&
679 ssh_gssapi_check_mechanism(&gssctxt,
680 &gss_supported->elements[mech], gss_host,
681 options.gss_client_identity)) {
682 ok = 1; /* Mechanism works */
691 authctxt->methoddata=(void *)gssctxt;
693 packet_start(SSH2_MSG_USERAUTH_REQUEST);
694 packet_put_cstring(authctxt->server_user);
695 packet_put_cstring(authctxt->service);
696 packet_put_cstring(authctxt->method->name);
700 packet_put_int((gss_supported->elements[mech].length) + 2);
701 packet_put_char(SSH_GSS_OIDTYPE);
702 packet_put_char(gss_supported->elements[mech].length);
703 packet_put_raw(gss_supported->elements[mech].elements,
704 gss_supported->elements[mech].length);
708 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
709 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
710 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
711 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
713 mech++; /* Move along to next candidate */
719 process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
721 Authctxt *authctxt = ctxt;
722 Gssctxt *gssctxt = authctxt->methoddata;
723 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
724 gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
725 gss_buffer_desc gssbuf;
726 OM_uint32 status, ms, flags;
729 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
730 recv_tok, &send_tok, &flags);
732 if (send_tok.length > 0) {
733 if (GSS_ERROR(status))
734 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
736 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
738 packet_put_string(send_tok.value, send_tok.length);
740 gss_release_buffer(&ms, &send_tok);
743 if (status == GSS_S_COMPLETE) {
744 /* send either complete or MIC, depending on mechanism */
745 if (strcmp(authctxt->method->name,"gssapi")==0 ||
746 (!(flags & GSS_C_INTEG_FLAG))) {
747 packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
750 ssh_gssapi_buildmic(&b, authctxt->server_user,
751 authctxt->service, "gssapi-with-mic");
753 gssbuf.value = buffer_ptr(&b);
754 gssbuf.length = buffer_len(&b);
756 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
758 if (!GSS_ERROR(status)) {
759 packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
760 packet_put_string(mic.value, mic.length);
766 gss_release_buffer(&ms, &mic);
775 input_gssapi_response(int type, u_int32_t plen, void *ctxt)
777 Authctxt *authctxt = ctxt;
782 if (authctxt == NULL)
783 fatal("input_gssapi_response: no authentication context");
784 gssctxt = authctxt->methoddata;
787 oidv = packet_get_string(&oidlen);
790 oidv[0] != SSH_GSS_OIDTYPE ||
791 oidv[1] != oidlen - 2) {
793 debug("Badly encoded mechanism OID received");
794 userauth(authctxt, NULL);
798 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
799 fatal("Server returned different OID than expected");
805 if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
806 /* Start again with next method on list */
807 debug("Trying to start again");
808 userauth(authctxt, NULL);
815 input_gssapi_token(int type, u_int32_t plen, void *ctxt)
817 Authctxt *authctxt = ctxt;
818 gss_buffer_desc recv_tok;
822 if (authctxt == NULL)
823 fatal("input_gssapi_response: no authentication context");
825 recv_tok.value = packet_get_string(&slen);
826 recv_tok.length = slen; /* safe typecast */
830 status = process_gssapi_token(ctxt, &recv_tok);
832 xfree(recv_tok.value);
834 if (GSS_ERROR(status)) {
835 /* Start again with the next method in the list */
836 userauth(authctxt, NULL);
843 input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
845 Authctxt *authctxt = ctxt;
847 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
848 gss_buffer_desc recv_tok;
849 OM_uint32 status, ms;
852 if (authctxt == NULL)
853 fatal("input_gssapi_response: no authentication context");
854 gssctxt = authctxt->methoddata;
856 recv_tok.value = packet_get_string(&len);
857 recv_tok.length = len;
861 /* Stick it into GSSAPI and see what it says */
862 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
863 &recv_tok, &send_tok, NULL);
865 xfree(recv_tok.value);
866 gss_release_buffer(&ms, &send_tok);
868 /* Server will be returning a failed packet after this one */
873 input_gssapi_error(int type, u_int32_t plen, void *ctxt)
879 maj=packet_get_int();
880 min=packet_get_int();
881 msg=packet_get_string(NULL);
882 lang=packet_get_string(NULL);
886 debug("Server GSSAPI Error:\n%s", msg);
893 const gss_OID_desc * const gss_mech_globus_gssapi_openssl;
894 #define is_gsi_oid(oid) \
895 (oid->length == gss_mech_globus_gssapi_openssl->length && \
896 (memcmp(oid->elements, gss_mech_globus_gssapi_openssl->elements, \
901 userauth_external(Authctxt *authctxt)
903 static int attempt = 0;
908 /* The client MUST NOT try this method if initial key exchange
909 was not performed using a GSSAPI-based key exchange
911 if (gss_kex_context == NULL) {
912 debug2("gsskex not performed, skipping external-keyx");
916 debug2("userauth_external");
917 packet_start(SSH2_MSG_USERAUTH_REQUEST);
919 if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
920 packet_put_cstring("");
923 packet_put_cstring(authctxt->server_user);
927 packet_put_cstring(authctxt->service);
928 packet_put_cstring(authctxt->method->name);
934 userauth_gsskeyex(Authctxt *authctxt)
937 gss_buffer_desc gssbuf;
938 gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
941 static int attempt = 0;
945 if (gss_kex_context == NULL) {
946 debug("No valid Key exchange context");
951 if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
952 ssh_gssapi_buildmic(&b, "", authctxt->service, "gssapi-keyex");
955 ssh_gssapi_buildmic(&b, authctxt->server_user, authctxt->service,
961 gssbuf.value = buffer_ptr(&b);
962 gssbuf.length = buffer_len(&b);
964 if (GSS_ERROR(ssh_gssapi_sign(gss_kex_context, &gssbuf, &mic))) {
969 packet_start(SSH2_MSG_USERAUTH_REQUEST);
971 if (options.implicit && is_gsi_oid(gss_kex_context->oid)) {
972 packet_put_cstring("");
975 packet_put_cstring(authctxt->server_user);
979 packet_put_cstring(authctxt->service);
980 packet_put_cstring(authctxt->method->name);
981 packet_put_string(mic.value, mic.length);
985 gss_release_buffer(&ms, &mic);
993 userauth_none(Authctxt *authctxt)
995 /* initial userauth request */
996 packet_start(SSH2_MSG_USERAUTH_REQUEST);
997 packet_put_cstring(authctxt->server_user);
998 packet_put_cstring(authctxt->service);
999 packet_put_cstring(authctxt->method->name);
1005 userauth_passwd(Authctxt *authctxt)
1007 static int attempt = 0;
1011 if (attempt++ >= options.number_of_password_prompts)
1015 error("Permission denied, please try again.");
1017 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1018 authctxt->server_user, authctxt->host);
1019 password = read_passphrase(prompt, 0);
1020 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1021 packet_put_cstring(authctxt->server_user);
1022 packet_put_cstring(authctxt->service);
1023 packet_put_cstring(authctxt->method->name);
1025 packet_put_cstring(password);
1026 memset(password, 0, strlen(password));
1028 packet_add_padding(64);
1031 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1032 &input_userauth_passwd_changereq);
1038 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1042 input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1044 Authctxt *authctxt = ctxt;
1045 char *info, *lang, *password = NULL, *retype = NULL;
1048 debug2("input_userauth_passwd_changereq");
1050 if (authctxt == NULL)
1051 fatal("input_userauth_passwd_changereq: "
1052 "no authentication context");
1054 info = packet_get_string(NULL);
1055 lang = packet_get_string(NULL);
1056 if (strlen(info) > 0)
1060 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1061 packet_put_cstring(authctxt->server_user);
1062 packet_put_cstring(authctxt->service);
1063 packet_put_cstring(authctxt->method->name);
1064 packet_put_char(1); /* additional info */
1065 snprintf(prompt, sizeof(prompt),
1066 "Enter %.30s@%.128s's old password: ",
1067 authctxt->server_user, authctxt->host);
1068 password = read_passphrase(prompt, 0);
1069 packet_put_cstring(password);
1070 memset(password, 0, strlen(password));
1073 while (password == NULL) {
1074 snprintf(prompt, sizeof(prompt),
1075 "Enter %.30s@%.128s's new password: ",
1076 authctxt->server_user, authctxt->host);
1077 password = read_passphrase(prompt, RP_ALLOW_EOF);
1078 if (password == NULL) {
1082 snprintf(prompt, sizeof(prompt),
1083 "Retype %.30s@%.128s's new password: ",
1084 authctxt->server_user, authctxt->host);
1085 retype = read_passphrase(prompt, 0);
1086 if (strcmp(password, retype) != 0) {
1087 memset(password, 0, strlen(password));
1089 logit("Mismatch; try again, EOF to quit.");
1092 memset(retype, 0, strlen(retype));
1095 packet_put_cstring(password);
1096 memset(password, 0, strlen(password));
1098 packet_add_padding(64);
1101 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1102 &input_userauth_passwd_changereq);
1107 pw_encrypt(const char *password, const char *crypt_scheme, const char *salt)
1109 /* OpenBSD crypt(3) handles all of these */
1110 if (strcmp(crypt_scheme, "crypt") == 0 ||
1111 strcmp(crypt_scheme, "bcrypt") == 0 ||
1112 strcmp(crypt_scheme, "md5crypt") == 0 ||
1113 strcmp(crypt_scheme, "crypt-extended") == 0)
1114 return xstrdup(crypt(password, salt));
1115 error("%s: unsupported password encryption scheme \"%.100s\"",
1116 __func__, crypt_scheme);
1121 jpake_password_to_secret(Authctxt *authctxt, const char *crypt_scheme,
1124 char prompt[256], *password, *crypted;
1129 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password (JPAKE): ",
1130 authctxt->server_user, authctxt->host);
1131 password = read_passphrase(prompt, 0);
1133 if ((crypted = pw_encrypt(password, crypt_scheme, salt)) == NULL) {
1134 logit("Disabling %s authentication", authctxt->method->name);
1135 authctxt->method->enabled = NULL;
1136 /* Continue with an empty password to fail gracefully */
1137 crypted = xstrdup("");
1141 debug3("%s: salt = %s", __func__, salt);
1142 debug3("%s: scheme = %s", __func__, crypt_scheme);
1143 debug3("%s: crypted = %s", __func__, crypted);
1146 if (hash_buffer(crypted, strlen(crypted), EVP_sha256(),
1147 &secret, &secret_len) != 0)
1148 fatal("%s: hash_buffer", __func__);
1150 bzero(password, strlen(password));
1151 bzero(crypted, strlen(crypted));
1155 if ((ret = BN_bin2bn(secret, secret_len, NULL)) == NULL)
1156 fatal("%s: BN_bin2bn (secret)", __func__);
1157 bzero(secret, secret_len);
1165 input_userauth_jpake_server_step1(int type, u_int32_t seq, void *ctxt)
1167 Authctxt *authctxt = ctxt;
1168 struct jpake_ctx *pctx = authctxt->methoddata;
1169 u_char *x3_proof, *x4_proof, *x2_s_proof;
1170 u_int x3_proof_len, x4_proof_len, x2_s_proof_len;
1171 char *crypt_scheme, *salt;
1173 /* Disable this message */
1174 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1, NULL);
1176 if ((pctx->g_x3 = BN_new()) == NULL ||
1177 (pctx->g_x4 = BN_new()) == NULL)
1178 fatal("%s: BN_new", __func__);
1180 /* Fetch step 1 values */
1181 crypt_scheme = packet_get_string(NULL);
1182 salt = packet_get_string(NULL);
1183 pctx->server_id = packet_get_string(&pctx->server_id_len);
1184 packet_get_bignum2(pctx->g_x3);
1185 packet_get_bignum2(pctx->g_x4);
1186 x3_proof = packet_get_string(&x3_proof_len);
1187 x4_proof = packet_get_string(&x4_proof_len);
1190 JPAKE_DEBUG_CTX((pctx, "step 1 received in %s", __func__));
1192 /* Obtain password and derive secret */
1193 pctx->s = jpake_password_to_secret(authctxt, crypt_scheme, salt);
1194 bzero(crypt_scheme, strlen(crypt_scheme));
1195 bzero(salt, strlen(salt));
1196 xfree(crypt_scheme);
1198 JPAKE_DEBUG_BN((pctx->s, "%s: s = ", __func__));
1200 /* Calculate step 2 values */
1201 jpake_step2(pctx->grp, pctx->s, pctx->g_x1,
1202 pctx->g_x3, pctx->g_x4, pctx->x2,
1203 pctx->server_id, pctx->server_id_len,
1204 pctx->client_id, pctx->client_id_len,
1205 x3_proof, x3_proof_len,
1206 x4_proof, x4_proof_len,
1208 &x2_s_proof, &x2_s_proof_len);
1210 bzero(x3_proof, x3_proof_len);
1211 bzero(x4_proof, x4_proof_len);
1215 JPAKE_DEBUG_CTX((pctx, "step 2 sending in %s", __func__));
1217 /* Send values for step 2 */
1218 packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP2);
1219 packet_put_bignum2(pctx->a);
1220 packet_put_string(x2_s_proof, x2_s_proof_len);
1223 bzero(x2_s_proof, x2_s_proof_len);
1226 /* Expect step 2 packet from peer */
1227 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2,
1228 input_userauth_jpake_server_step2);
1233 input_userauth_jpake_server_step2(int type, u_int32_t seq, void *ctxt)
1235 Authctxt *authctxt = ctxt;
1236 struct jpake_ctx *pctx = authctxt->methoddata;
1238 u_int x4_s_proof_len;
1240 /* Disable this message */
1241 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2, NULL);
1243 if ((pctx->b = BN_new()) == NULL)
1244 fatal("%s: BN_new", __func__);
1246 /* Fetch step 2 values */
1247 packet_get_bignum2(pctx->b);
1248 x4_s_proof = packet_get_string(&x4_s_proof_len);
1251 JPAKE_DEBUG_CTX((pctx, "step 2 received in %s", __func__));
1253 /* Derive shared key and calculate confirmation hash */
1254 jpake_key_confirm(pctx->grp, pctx->s, pctx->b,
1255 pctx->x2, pctx->g_x1, pctx->g_x2, pctx->g_x3, pctx->g_x4,
1256 pctx->client_id, pctx->client_id_len,
1257 pctx->server_id, pctx->server_id_len,
1258 session_id2, session_id2_len,
1259 x4_s_proof, x4_s_proof_len,
1261 &pctx->h_k_cid_sessid, &pctx->h_k_cid_sessid_len);
1263 bzero(x4_s_proof, x4_s_proof_len);
1266 JPAKE_DEBUG_CTX((pctx, "confirm sending in %s", __func__));
1268 /* Send key confirmation proof */
1269 packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_CONFIRM);
1270 packet_put_string(pctx->h_k_cid_sessid, pctx->h_k_cid_sessid_len);
1273 /* Expect confirmation from peer */
1274 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM,
1275 input_userauth_jpake_server_confirm);
1280 input_userauth_jpake_server_confirm(int type, u_int32_t seq, void *ctxt)
1282 Authctxt *authctxt = ctxt;
1283 struct jpake_ctx *pctx = authctxt->methoddata;
1285 /* Disable this message */
1286 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM, NULL);
1288 pctx->h_k_sid_sessid = packet_get_string(&pctx->h_k_sid_sessid_len);
1291 JPAKE_DEBUG_CTX((pctx, "confirm received in %s", __func__));
1293 /* Verify expected confirmation hash */
1294 if (jpake_check_confirm(pctx->k,
1295 pctx->server_id, pctx->server_id_len,
1296 session_id2, session_id2_len,
1297 pctx->h_k_sid_sessid, pctx->h_k_sid_sessid_len) == 1)
1298 debug("%s: %s success", __func__, authctxt->method->name);
1300 debug("%s: confirmation mismatch", __func__);
1301 /* XXX stash this so if auth succeeds then we can warn/kill */
1304 userauth_jpake_cleanup(authctxt);
1309 identity_sign(Identity *id, u_char **sigp, u_int *lenp,
1310 u_char *data, u_int datalen)
1315 /* the agent supports this key */
1317 return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
1320 * we have already loaded the private key or
1321 * the private key is stored in external hardware
1323 if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
1324 return (key_sign(id->key, sigp, lenp, data, datalen));
1325 /* load the private key from the file */
1326 if ((prv = load_identity_file(id->filename)) == NULL)
1328 ret = key_sign(prv, sigp, lenp, data, datalen);
1334 sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1337 u_char *blob, *signature;
1338 u_int bloblen, slen;
1343 debug3("sign_and_send_pubkey");
1345 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1346 /* we cannot handle this key */
1347 debug3("sign_and_send_pubkey: cannot handle key");
1350 /* data to be signed */
1352 if (datafellows & SSH_OLD_SESSIONID) {
1353 buffer_append(&b, session_id2, session_id2_len);
1354 skip = session_id2_len;
1356 buffer_put_string(&b, session_id2, session_id2_len);
1357 skip = buffer_len(&b);
1359 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1360 buffer_put_cstring(&b, authctxt->server_user);
1361 buffer_put_cstring(&b,
1362 datafellows & SSH_BUG_PKSERVICE ?
1365 if (datafellows & SSH_BUG_PKAUTH) {
1366 buffer_put_char(&b, have_sig);
1368 buffer_put_cstring(&b, authctxt->method->name);
1369 buffer_put_char(&b, have_sig);
1370 buffer_put_cstring(&b, key_ssh_name(id->key));
1372 buffer_put_string(&b, blob, bloblen);
1374 /* generate signature */
1375 ret = identity_sign(id, &signature, &slen,
1376 buffer_ptr(&b), buffer_len(&b));
1385 if (datafellows & SSH_BUG_PKSERVICE) {
1387 buffer_append(&b, session_id2, session_id2_len);
1388 skip = session_id2_len;
1389 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1390 buffer_put_cstring(&b, authctxt->server_user);
1391 buffer_put_cstring(&b, authctxt->service);
1392 buffer_put_cstring(&b, authctxt->method->name);
1393 buffer_put_char(&b, have_sig);
1394 if (!(datafellows & SSH_BUG_PKAUTH))
1395 buffer_put_cstring(&b, key_ssh_name(id->key));
1396 buffer_put_string(&b, blob, bloblen);
1400 /* append signature */
1401 buffer_put_string(&b, signature, slen);
1404 /* skip session id and packet type */
1405 if (buffer_len(&b) < skip + 1)
1406 fatal("userauth_pubkey: internal error");
1407 buffer_consume(&b, skip + 1);
1409 /* put remaining data from buffer into packet */
1410 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1411 packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1419 send_pubkey_test(Authctxt *authctxt, Identity *id)
1422 u_int bloblen, have_sig = 0;
1424 debug3("send_pubkey_test");
1426 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1427 /* we cannot handle this key */
1428 debug3("send_pubkey_test: cannot handle key");
1431 /* register callback for USERAUTH_PK_OK message */
1432 dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1434 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1435 packet_put_cstring(authctxt->server_user);
1436 packet_put_cstring(authctxt->service);
1437 packet_put_cstring(authctxt->method->name);
1438 packet_put_char(have_sig);
1439 if (!(datafellows & SSH_BUG_PKAUTH))
1440 packet_put_cstring(key_ssh_name(id->key));
1441 packet_put_string(blob, bloblen);
1448 load_identity_file(char *filename)
1451 char prompt[300], *passphrase;
1452 int perm_ok, quit, i;
1455 if (stat(filename, &st) < 0) {
1456 debug3("no such identity: %s", filename);
1459 private = key_load_private_type(KEY_UNSPEC, filename, "", NULL, &perm_ok);
1462 if (private == NULL) {
1463 if (options.batch_mode)
1465 snprintf(prompt, sizeof prompt,
1466 "Enter passphrase for key '%.100s': ", filename);
1467 for (i = 0; i < options.number_of_password_prompts; i++) {
1468 passphrase = read_passphrase(prompt, 0);
1469 if (strcmp(passphrase, "") != 0) {
1470 private = key_load_private_type(KEY_UNSPEC,
1471 filename, passphrase, NULL, NULL);
1474 debug2("no passphrase given, try next key");
1477 memset(passphrase, 0, strlen(passphrase));
1479 if (private != NULL || quit)
1481 debug2("bad passphrase given, try again...");
1488 * try keys in the following order:
1489 * 1. agent keys that are found in the config file
1490 * 2. other agent keys
1491 * 3. keys that are only listed in the config file
1494 pubkey_prepare(Authctxt *authctxt)
1497 Idlist agent, files, *preferred;
1499 AuthenticationConnection *ac;
1503 TAILQ_INIT(&agent); /* keys from the agent */
1504 TAILQ_INIT(&files); /* keys from the config file */
1505 preferred = &authctxt->keys;
1506 TAILQ_INIT(preferred); /* preferred order of keys */
1508 /* list of keys stored in the filesystem */
1509 for (i = 0; i < options.num_identity_files; i++) {
1510 key = options.identity_keys[i];
1511 if (key && key->type == KEY_RSA1)
1513 options.identity_keys[i] = NULL;
1514 id = xcalloc(1, sizeof(*id));
1516 id->filename = xstrdup(options.identity_files[i]);
1517 TAILQ_INSERT_TAIL(&files, id, next);
1519 /* list of keys supported by the agent */
1520 if ((ac = ssh_get_authentication_connection())) {
1521 for (key = ssh_get_first_identity(ac, &comment, 2);
1523 key = ssh_get_next_identity(ac, &comment, 2)) {
1525 TAILQ_FOREACH(id, &files, next) {
1526 /* agent keys from the config file are preferred */
1527 if (key_equal(key, id->key)) {
1530 TAILQ_REMOVE(&files, id, next);
1531 TAILQ_INSERT_TAIL(preferred, id, next);
1537 if (!found && !options.identities_only) {
1538 id = xcalloc(1, sizeof(*id));
1540 id->filename = comment;
1542 TAILQ_INSERT_TAIL(&agent, id, next);
1545 /* append remaining agent keys */
1546 for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1547 TAILQ_REMOVE(&agent, id, next);
1548 TAILQ_INSERT_TAIL(preferred, id, next);
1550 authctxt->agent = ac;
1552 /* append remaining keys from the config file */
1553 for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1554 TAILQ_REMOVE(&files, id, next);
1555 TAILQ_INSERT_TAIL(preferred, id, next);
1557 TAILQ_FOREACH(id, preferred, next) {
1558 debug2("key: %s (%p)", id->filename, id->key);
1563 pubkey_cleanup(Authctxt *authctxt)
1567 if (authctxt->agent != NULL)
1568 ssh_close_authentication_connection(authctxt->agent);
1569 for (id = TAILQ_FIRST(&authctxt->keys); id;
1570 id = TAILQ_FIRST(&authctxt->keys)) {
1571 TAILQ_REMOVE(&authctxt->keys, id, next);
1575 xfree(id->filename);
1581 userauth_pubkey(Authctxt *authctxt)
1586 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1589 /* move key to the end of the queue */
1590 TAILQ_REMOVE(&authctxt->keys, id, next);
1591 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1593 * send a test message if we have the public key. for
1594 * encrypted keys we cannot do this and have to load the
1595 * private key instead
1597 if (id->key && id->key->type != KEY_RSA1) {
1598 debug("Offering public key: %s", id->filename);
1599 sent = send_pubkey_test(authctxt, id);
1600 } else if (id->key == NULL) {
1601 debug("Trying private key: %s", id->filename);
1602 id->key = load_identity_file(id->filename);
1603 if (id->key != NULL) {
1605 sent = sign_and_send_pubkey(authctxt, id);
1617 * Send userauth request message specifying keyboard-interactive method.
1620 userauth_kbdint(Authctxt *authctxt)
1622 static int attempt = 0;
1624 if (attempt++ >= options.number_of_password_prompts)
1626 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1627 if (attempt > 1 && !authctxt->info_req_seen) {
1628 debug3("userauth_kbdint: disable: no info_req_seen");
1629 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1633 debug2("userauth_kbdint");
1634 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1635 packet_put_cstring(authctxt->server_user);
1636 packet_put_cstring(authctxt->service);
1637 packet_put_cstring(authctxt->method->name);
1638 packet_put_cstring(""); /* lang */
1639 packet_put_cstring(options.kbd_interactive_devices ?
1640 options.kbd_interactive_devices : "");
1643 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1648 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1651 input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1653 Authctxt *authctxt = ctxt;
1654 char *name, *inst, *lang, *prompt, *response;
1655 u_int num_prompts, i;
1658 debug2("input_userauth_info_req");
1660 if (authctxt == NULL)
1661 fatal("input_userauth_info_req: no authentication context");
1663 authctxt->info_req_seen = 1;
1665 name = packet_get_string(NULL);
1666 inst = packet_get_string(NULL);
1667 lang = packet_get_string(NULL);
1668 if (strlen(name) > 0)
1670 if (strlen(inst) > 0)
1676 num_prompts = packet_get_int();
1678 * Begin to build info response packet based on prompts requested.
1679 * We commit to providing the correct number of responses, so if
1680 * further on we run into a problem that prevents this, we have to
1681 * be sure and clean this up and send a correct error response.
1683 packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1684 packet_put_int(num_prompts);
1686 debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1687 for (i = 0; i < num_prompts; i++) {
1688 prompt = packet_get_string(NULL);
1689 echo = packet_get_char();
1691 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1693 packet_put_cstring(response);
1694 memset(response, 0, strlen(response));
1698 packet_check_eom(); /* done with parsing incoming message. */
1700 packet_add_padding(64);
1705 ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1706 u_char *data, u_int datalen)
1711 int to[2], from[2], status, version = 2;
1713 debug2("ssh_keysign called");
1715 if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1716 error("ssh_keysign: no installed: %s", strerror(errno));
1719 if (fflush(stdout) != 0)
1720 error("ssh_keysign: fflush: %s", strerror(errno));
1722 error("ssh_keysign: pipe: %s", strerror(errno));
1725 if (pipe(from) < 0) {
1726 error("ssh_keysign: pipe: %s", strerror(errno));
1729 if ((pid = fork()) < 0) {
1730 error("ssh_keysign: fork: %s", strerror(errno));
1734 permanently_drop_suid(getuid());
1736 if (dup2(from[1], STDOUT_FILENO) < 0)
1737 fatal("ssh_keysign: dup2: %s", strerror(errno));
1739 if (dup2(to[0], STDIN_FILENO) < 0)
1740 fatal("ssh_keysign: dup2: %s", strerror(errno));
1743 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1744 fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1751 buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1752 buffer_put_string(&b, data, datalen);
1753 if (ssh_msg_send(to[1], version, &b) == -1)
1754 fatal("ssh_keysign: couldn't send request");
1756 if (ssh_msg_recv(from[0], &b) < 0) {
1757 error("ssh_keysign: no reply");
1764 while (waitpid(pid, &status, 0) < 0)
1768 if (buffer_get_char(&b) != version) {
1769 error("ssh_keysign: bad version");
1773 *sigp = buffer_get_string(&b, lenp);
1780 userauth_hostbased(Authctxt *authctxt)
1782 Key *private = NULL;
1783 Sensitive *sensitive = authctxt->sensitive;
1785 u_char *signature, *blob;
1786 char *chost, *pkalg, *p, myname[NI_MAXHOST];
1787 const char *service;
1789 int ok, i, len, found = 0;
1791 /* check for a useful key */
1792 for (i = 0; i < sensitive->nkeys; i++) {
1793 private = sensitive->keys[i];
1794 if (private && private->type != KEY_RSA1) {
1796 /* we take and free the key */
1797 sensitive->keys[i] = NULL;
1802 debug("No more client hostkeys for hostbased authentication.");
1805 if (key_to_blob(private, &blob, &blen) == 0) {
1809 /* figure out a name for the client host */
1811 if (packet_connection_is_on_socket())
1812 p = get_local_name(packet_get_connection_in());
1814 if (gethostname(myname, sizeof(myname)) == -1) {
1815 verbose("userauth_hostbased: gethostname: %s",
1818 p = xstrdup(myname);
1821 error("userauth_hostbased: cannot get local ipaddr/name");
1826 len = strlen(p) + 2;
1827 xasprintf(&chost, "%s.", p);
1828 debug2("userauth_hostbased: chost %s", chost);
1831 service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1833 pkalg = xstrdup(key_ssh_name(private));
1835 /* construct data */
1836 buffer_put_string(&b, session_id2, session_id2_len);
1837 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1838 buffer_put_cstring(&b, authctxt->server_user);
1839 buffer_put_cstring(&b, service);
1840 buffer_put_cstring(&b, authctxt->method->name);
1841 buffer_put_cstring(&b, pkalg);
1842 buffer_put_string(&b, blob, blen);
1843 buffer_put_cstring(&b, chost);
1844 buffer_put_cstring(&b, authctxt->local_user);
1848 if (sensitive->external_keysign)
1849 ok = ssh_keysign(private, &signature, &slen,
1850 buffer_ptr(&b), buffer_len(&b));
1852 ok = key_sign(private, &signature, &slen,
1853 buffer_ptr(&b), buffer_len(&b));
1857 error("key_sign failed");
1863 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1864 packet_put_cstring(authctxt->server_user);
1865 packet_put_cstring(authctxt->service);
1866 packet_put_cstring(authctxt->method->name);
1867 packet_put_cstring(pkalg);
1868 packet_put_string(blob, blen);
1869 packet_put_cstring(chost);
1870 packet_put_cstring(authctxt->local_user);
1871 packet_put_string(signature, slen);
1872 memset(signature, 's', slen);
1884 userauth_jpake(Authctxt *authctxt)
1886 struct jpake_ctx *pctx;
1887 u_char *x1_proof, *x2_proof;
1888 u_int x1_proof_len, x2_proof_len;
1889 static int attempt = 0; /* XXX share with userauth_password's? */
1891 if (attempt++ >= options.number_of_password_prompts)
1894 error("Permission denied, please try again.");
1896 if (authctxt->methoddata != NULL)
1897 fatal("%s: authctxt->methoddata already set (%p)",
1898 __func__, authctxt->methoddata);
1900 authctxt->methoddata = pctx = jpake_new();
1903 * Send request immediately, to get the protocol going while
1904 * we do the initial computations.
1906 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1907 packet_put_cstring(authctxt->server_user);
1908 packet_put_cstring(authctxt->service);
1909 packet_put_cstring(authctxt->method->name);
1911 packet_write_wait();
1913 jpake_step1(pctx->grp,
1914 &pctx->client_id, &pctx->client_id_len,
1915 &pctx->x1, &pctx->x2, &pctx->g_x1, &pctx->g_x2,
1916 &x1_proof, &x1_proof_len,
1917 &x2_proof, &x2_proof_len);
1919 JPAKE_DEBUG_CTX((pctx, "step 1 sending in %s", __func__));
1921 packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP1);
1922 packet_put_string(pctx->client_id, pctx->client_id_len);
1923 packet_put_bignum2(pctx->g_x1);
1924 packet_put_bignum2(pctx->g_x2);
1925 packet_put_string(x1_proof, x1_proof_len);
1926 packet_put_string(x2_proof, x2_proof_len);
1929 bzero(x1_proof, x1_proof_len);
1930 bzero(x2_proof, x2_proof_len);
1934 /* Expect step 1 packet from peer */
1935 dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1,
1936 input_userauth_jpake_server_step1);
1942 userauth_jpake_cleanup(Authctxt *authctxt)
1944 debug3("%s: clean up", __func__);
1945 if (authctxt->methoddata != NULL) {
1946 jpake_free(authctxt->methoddata);
1947 authctxt->methoddata = NULL;
1952 /* find auth method */
1955 * given auth method name, if configurable options permit this method fill
1956 * in auth_ident field and return true, otherwise return false.
1959 authmethod_is_enabled(Authmethod *method)
1963 /* return false if options indicate this method is disabled */
1964 if (method->enabled == NULL || *method->enabled == 0)
1966 /* return false if batch mode is enabled but method needs interactive mode */
1967 if (method->batch_flag != NULL && *method->batch_flag != 0)
1973 authmethod_lookup(const char *name)
1975 Authmethod *method = NULL;
1977 for (method = authmethods; method->name != NULL; method++)
1978 if (strcmp(name, method->name) == 0)
1980 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1984 /* XXX internal state */
1985 static Authmethod *current = NULL;
1986 static char *supported = NULL;
1987 static char *preferred = NULL;
1990 * Given the authentication method list sent by the server, return the
1991 * next method we should try. If the server initially sends a nil list,
1992 * use a built-in default list.
1995 authmethod_get(char *authlist)
2000 /* Use a suitable default if we're passed a nil list. */
2001 if (authlist == NULL || strlen(authlist) == 0)
2002 authlist = options.preferred_authentications;
2004 if (supported == NULL || strcmp(authlist, supported) != 0) {
2005 debug3("start over, passed a different list %s", authlist);
2006 if (supported != NULL)
2008 supported = xstrdup(authlist);
2009 preferred = options.preferred_authentications;
2010 debug3("preferred %s", preferred);
2012 } else if (current != NULL && authmethod_is_enabled(current))
2016 if ((name = match_list(preferred, supported, &next)) == NULL) {
2017 debug("No more authentication methods to try.");
2022 debug3("authmethod_lookup %s", name);
2023 debug3("remaining preferred: %s", preferred);
2024 if ((current = authmethod_lookup(name)) != NULL &&
2025 authmethod_is_enabled(current)) {
2026 debug3("authmethod_is_enabled %s", name);
2027 debug("Next authentication method: %s", name);
2034 authmethods_get(void)
2036 Authmethod *method = NULL;
2041 for (method = authmethods; method->name != NULL; method++) {
2042 if (authmethod_is_enabled(method)) {
2043 if (buffer_len(&b) > 0)
2044 buffer_append(&b, ",", 1);
2045 buffer_append(&b, method->name, strlen(method->name));
2048 buffer_append(&b, "\0", 1);
2049 list = xstrdup(buffer_ptr(&b));