auth/gensec: make sure there's only one pending gensec_update_send() per context
[vlendec/samba-autobuild/.git] / auth / gensec / gensec.c
1 /*
2    Unix SMB/CIFS implementation.
3
4    Generic Authentication Interface
5
6    Copyright (C) Andrew Tridgell 2003
7    Copyright (C) Andrew Bartlett <abartlet@samba.org> 2004-2006
8
9    This program is free software; you can redistribute it and/or modify
10    it under the terms of the GNU General Public License as published by
11    the Free Software Foundation; either version 3 of the License, or
12    (at your option) any later version.
13
14    This program is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17    GNU General Public License for more details.
18
19    You should have received a copy of the GNU General Public License
20    along with this program.  If not, see <http://www.gnu.org/licenses/>.
21 */
22
23 #include "includes.h"
24 #include "system/network.h"
25 #define TEVENT_DEPRECATED 1
26 #include <tevent.h>
27 #include "lib/tsocket/tsocket.h"
28 #include "lib/util/tevent_ntstatus.h"
29 #include "auth/gensec/gensec.h"
30 #include "auth/gensec/gensec_internal.h"
31 #include "librpc/gen_ndr/dcerpc.h"
32 #include "auth/common_auth.h"
33
34 _PRIVATE_ NTSTATUS gensec_may_reset_crypto(struct gensec_security *gensec_security,
35                                            bool full_reset)
36 {
37         if (!gensec_security->ops->may_reset_crypto) {
38                 return NT_STATUS_OK;
39         }
40
41         return gensec_security->ops->may_reset_crypto(gensec_security, full_reset);
42 }
43
44 /*
45   wrappers for the gensec function pointers
46 */
47 _PUBLIC_ NTSTATUS gensec_unseal_packet(struct gensec_security *gensec_security,
48                               uint8_t *data, size_t length,
49                               const uint8_t *whole_pdu, size_t pdu_length,
50                               const DATA_BLOB *sig)
51 {
52         if (!gensec_security->ops->unseal_packet) {
53                 return NT_STATUS_NOT_IMPLEMENTED;
54         }
55         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
56                 return NT_STATUS_INVALID_PARAMETER;
57         }
58         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
59                 return NT_STATUS_INVALID_PARAMETER;
60         }
61         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_DCE_STYLE)) {
62                 return NT_STATUS_INVALID_PARAMETER;
63         }
64
65         return gensec_security->ops->unseal_packet(gensec_security,
66                                                    data, length,
67                                                    whole_pdu, pdu_length,
68                                                    sig);
69 }
70
71 _PUBLIC_ NTSTATUS gensec_check_packet(struct gensec_security *gensec_security,
72                              const uint8_t *data, size_t length,
73                              const uint8_t *whole_pdu, size_t pdu_length,
74                              const DATA_BLOB *sig)
75 {
76         if (!gensec_security->ops->check_packet) {
77                 return NT_STATUS_NOT_IMPLEMENTED;
78         }
79         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
80                 return NT_STATUS_INVALID_PARAMETER;
81         }
82
83         return gensec_security->ops->check_packet(gensec_security, data, length, whole_pdu, pdu_length, sig);
84 }
85
86 _PUBLIC_ NTSTATUS gensec_seal_packet(struct gensec_security *gensec_security,
87                             TALLOC_CTX *mem_ctx,
88                             uint8_t *data, size_t length,
89                             const uint8_t *whole_pdu, size_t pdu_length,
90                             DATA_BLOB *sig)
91 {
92         if (!gensec_security->ops->seal_packet) {
93                 return NT_STATUS_NOT_IMPLEMENTED;
94         }
95         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
96                 return NT_STATUS_INVALID_PARAMETER;
97         }
98         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
99                 return NT_STATUS_INVALID_PARAMETER;
100         }
101         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_DCE_STYLE)) {
102                 return NT_STATUS_INVALID_PARAMETER;
103         }
104
105         return gensec_security->ops->seal_packet(gensec_security, mem_ctx, data, length, whole_pdu, pdu_length, sig);
106 }
107
108 _PUBLIC_ NTSTATUS gensec_sign_packet(struct gensec_security *gensec_security,
109                             TALLOC_CTX *mem_ctx,
110                             const uint8_t *data, size_t length,
111                             const uint8_t *whole_pdu, size_t pdu_length,
112                             DATA_BLOB *sig)
113 {
114         if (!gensec_security->ops->sign_packet) {
115                 return NT_STATUS_NOT_IMPLEMENTED;
116         }
117         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
118                 return NT_STATUS_INVALID_PARAMETER;
119         }
120
121         return gensec_security->ops->sign_packet(gensec_security, mem_ctx, data, length, whole_pdu, pdu_length, sig);
122 }
123
124 _PUBLIC_ size_t gensec_sig_size(struct gensec_security *gensec_security, size_t data_size)
125 {
126         if (!gensec_security->ops->sig_size) {
127                 return 0;
128         }
129         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
130                 return 0;
131         }
132         if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
133                 if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_DCE_STYLE)) {
134                         return 0;
135                 }
136         }
137
138         return gensec_security->ops->sig_size(gensec_security, data_size);
139 }
140
141 _PUBLIC_ size_t gensec_max_wrapped_size(struct gensec_security *gensec_security)
142 {
143         if (!gensec_security->ops->max_wrapped_size) {
144                 return (1 << 17);
145         }
146
147         return gensec_security->ops->max_wrapped_size(gensec_security);
148 }
149
150 _PUBLIC_ size_t gensec_max_input_size(struct gensec_security *gensec_security)
151 {
152         if (!gensec_security->ops->max_input_size) {
153                 return (1 << 17) - gensec_sig_size(gensec_security, 1 << 17);
154         }
155
156         return gensec_security->ops->max_input_size(gensec_security);
157 }
158
159 _PUBLIC_ NTSTATUS gensec_wrap(struct gensec_security *gensec_security,
160                      TALLOC_CTX *mem_ctx,
161                      const DATA_BLOB *in,
162                      DATA_BLOB *out)
163 {
164         if (!gensec_security->ops->wrap) {
165                 return NT_STATUS_NOT_IMPLEMENTED;
166         }
167         return gensec_security->ops->wrap(gensec_security, mem_ctx, in, out);
168 }
169
170 _PUBLIC_ NTSTATUS gensec_unwrap(struct gensec_security *gensec_security,
171                        TALLOC_CTX *mem_ctx,
172                        const DATA_BLOB *in,
173                        DATA_BLOB *out)
174 {
175         if (!gensec_security->ops->unwrap) {
176                 return NT_STATUS_NOT_IMPLEMENTED;
177         }
178         return gensec_security->ops->unwrap(gensec_security, mem_ctx, in, out);
179 }
180
181 _PUBLIC_ NTSTATUS gensec_session_key(struct gensec_security *gensec_security,
182                                      TALLOC_CTX *mem_ctx,
183                                      DATA_BLOB *session_key)
184 {
185         if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SESSION_KEY)) {
186                 return NT_STATUS_NO_USER_SESSION_KEY;
187         }
188
189         if (!gensec_security->ops->session_key) {
190                 return NT_STATUS_NOT_IMPLEMENTED;
191         }
192
193         return gensec_security->ops->session_key(gensec_security, mem_ctx, session_key);
194 }
195
196 const char *gensec_final_auth_type(struct gensec_security *gensec_security)
197 {
198         if (!gensec_security->ops->final_auth_type) {
199                 return gensec_security->ops->name;
200         }
201
202         return gensec_security->ops->final_auth_type(gensec_security);
203 }
204
205 /*
206  * Log details of a successful GENSEC authorization to a service.
207  *
208  * Only successful authorizations are logged, as only these call gensec_session_info()
209  *
210  * The service may later refuse authorization due to an ACL.
211  *
212  */
213 static void log_successful_gensec_authz_event(struct gensec_security *gensec_security,
214                                               struct auth_session_info *session_info)
215 {
216         const struct tsocket_address *remote
217                 = gensec_get_remote_address(gensec_security);
218         const struct tsocket_address *local
219                 = gensec_get_local_address(gensec_security);
220         const char *service_description
221                 = gensec_get_target_service_description(gensec_security);
222         const char *final_auth_type
223                 = gensec_final_auth_type(gensec_security);
224         const char *transport_protection = NULL;
225         if (gensec_security->want_features & GENSEC_FEATURE_SMB_TRANSPORT) {
226                 transport_protection = AUTHZ_TRANSPORT_PROTECTION_SMB;
227         } else if (gensec_security->want_features & GENSEC_FEATURE_LDAPS_TRANSPORT) {
228                 transport_protection = AUTHZ_TRANSPORT_PROTECTION_TLS;
229         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
230                 transport_protection = AUTHZ_TRANSPORT_PROTECTION_SEAL;
231         } else if (gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
232                 transport_protection = AUTHZ_TRANSPORT_PROTECTION_SIGN;
233         } else {
234                 transport_protection = AUTHZ_TRANSPORT_PROTECTION_NONE;
235         }
236         log_successful_authz_event(gensec_security->auth_context->msg_ctx,
237                                    gensec_security->auth_context->lp_ctx,
238                                    remote, local,
239                                    service_description,
240                                    final_auth_type,
241                                    transport_protection,
242                                    session_info);
243 }
244
245
246 /**
247  * Return the credentials of a logged on user, including session keys
248  * etc.
249  *
250  * Only valid after a successful authentication
251  *
252  * May only be called once per authentication.  This will also make an
253  * authorization log entry, as it is already called by all the
254  * callers.
255  *
256  */
257
258 _PUBLIC_ NTSTATUS gensec_session_info(struct gensec_security *gensec_security,
259                                       TALLOC_CTX *mem_ctx,
260                                       struct auth_session_info **session_info)
261 {
262         NTSTATUS status;
263         if (!gensec_security->ops->session_info) {
264                 return NT_STATUS_NOT_IMPLEMENTED;
265         }
266         status = gensec_security->ops->session_info(gensec_security, mem_ctx, session_info);
267
268         if (NT_STATUS_IS_OK(status) && !gensec_security->subcontext
269             && (gensec_security->want_features & GENSEC_FEATURE_NO_AUTHZ_LOG) == 0) {
270                 log_successful_gensec_authz_event(gensec_security, *session_info);
271         }
272
273         return status;
274 }
275
276 _PUBLIC_ void gensec_set_max_update_size(struct gensec_security *gensec_security,
277                                 uint32_t max_update_size)
278 {
279         gensec_security->max_update_size = max_update_size;
280 }
281
282 _PUBLIC_ size_t gensec_max_update_size(struct gensec_security *gensec_security)
283 {
284         if (gensec_security->max_update_size == 0) {
285                 return UINT32_MAX;
286         }
287
288         return gensec_security->max_update_size;
289 }
290
291 static NTSTATUS gensec_verify_features(struct gensec_security *gensec_security)
292 {
293         /*
294          * gensec_want_feature(GENSEC_FEATURE_SIGN)
295          * and
296          * gensec_want_feature(GENSEC_FEATURE_SEAL)
297          * require these flags to be available.
298          */
299         if (gensec_security->want_features & GENSEC_FEATURE_SIGN) {
300                 if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
301                         DEBUG(0,("Did not manage to negotiate mandatory feature "
302                                  "SIGN\n"));
303                         return NT_STATUS_ACCESS_DENIED;
304                 }
305         }
306         if (gensec_security->want_features & GENSEC_FEATURE_SEAL) {
307                 if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SEAL)) {
308                         DEBUG(0,("Did not manage to negotiate mandatory feature "
309                                  "SEAL\n"));
310                         return NT_STATUS_ACCESS_DENIED;
311                 }
312                 if (!gensec_have_feature(gensec_security, GENSEC_FEATURE_SIGN)) {
313                         DEBUG(0,("Did not manage to negotiate mandatory feature "
314                                  "SIGN for SEAL\n"));
315                         return NT_STATUS_ACCESS_DENIED;
316                 }
317         }
318
319         return NT_STATUS_OK;
320 }
321
322 _PUBLIC_ NTSTATUS gensec_update_ev(struct gensec_security *gensec_security,
323                                    TALLOC_CTX *out_mem_ctx,
324                                    struct tevent_context *ev,
325                                    const DATA_BLOB in, DATA_BLOB *out)
326 {
327         NTSTATUS status;
328         const struct gensec_security_ops *ops = gensec_security->ops;
329         TALLOC_CTX *frame = NULL;
330         struct tevent_req *subreq = NULL;
331         bool ok;
332
333         if (gensec_security->child_security != NULL) {
334                 return NT_STATUS_INVALID_PARAMETER;
335         }
336
337         frame = talloc_stackframe();
338
339         if (ev == NULL) {
340                 ev = samba_tevent_context_init(frame);
341                 if (ev == NULL) {
342                         status = NT_STATUS_NO_MEMORY;
343                         goto fail;
344                 }
345
346                 /*
347                  * TODO: remove this hack once the backends
348                  * are fixed.
349                  */
350                 tevent_loop_allow_nesting(ev);
351         }
352
353         subreq = ops->update_send(frame, ev, gensec_security, in);
354         if (subreq == NULL) {
355                 status = NT_STATUS_NO_MEMORY;
356                 goto fail;
357         }
358         ok = tevent_req_poll_ntstatus(subreq, ev, &status);
359         if (!ok) {
360                 goto fail;
361         }
362         status = ops->update_recv(subreq, out_mem_ctx, out);
363         if (!NT_STATUS_IS_OK(status)) {
364                 goto fail;
365         }
366
367         /*
368          * Because callers using the
369          * gensec_start_mech_by_auth_type() never call
370          * gensec_want_feature(), it isn't sensible for them
371          * to have to call gensec_have_feature() manually, and
372          * these are not points of negotiation, but are
373          * asserted by the client
374          */
375         status = gensec_verify_features(gensec_security);
376  fail:
377         TALLOC_FREE(frame);
378         return status;
379 }
380
381 /**
382  * Next state function for the GENSEC state machine
383  *
384  * @param gensec_security GENSEC State
385  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
386  * @param in The request, as a DATA_BLOB
387  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
388  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
389  *                or NT_STATUS_OK if the user is authenticated.
390  */
391
392 _PUBLIC_ NTSTATUS gensec_update(struct gensec_security *gensec_security,
393                                 TALLOC_CTX *out_mem_ctx,
394                                 const DATA_BLOB in, DATA_BLOB *out)
395 {
396         return gensec_update_ev(gensec_security, out_mem_ctx, NULL, in, out);
397 }
398
399 struct gensec_update_state {
400         const struct gensec_security_ops *ops;
401         struct gensec_security *gensec_security;
402         NTSTATUS status;
403         DATA_BLOB out;
404 };
405
406 static void gensec_update_cleanup(struct tevent_req *req,
407                                   enum tevent_req_state req_state);
408 static void gensec_update_done(struct tevent_req *subreq);
409
410 /**
411  * Next state function for the GENSEC state machine async version
412  *
413  * @param mem_ctx The memory context for the request
414  * @param ev The event context for the request
415  * @param gensec_security GENSEC State
416  * @param in The request, as a DATA_BLOB
417  *
418  * @return The request handle or NULL on no memory failure
419  */
420
421 _PUBLIC_ struct tevent_req *gensec_update_send(TALLOC_CTX *mem_ctx,
422                                                struct tevent_context *ev,
423                                                struct gensec_security *gensec_security,
424                                                const DATA_BLOB in)
425 {
426         struct tevent_req *req = NULL;
427         struct gensec_update_state *state = NULL;
428         struct tevent_req *subreq = NULL;
429
430         req = tevent_req_create(mem_ctx, &state,
431                                 struct gensec_update_state);
432         if (req == NULL) {
433                 return NULL;
434         }
435         state->ops = gensec_security->ops;
436         state->gensec_security = gensec_security;
437
438         if (gensec_security->update_busy_ptr != NULL) {
439                 tevent_req_nterror(req, NT_STATUS_INTERNAL_ERROR);
440                 return tevent_req_post(req, ev);
441         }
442
443         if (gensec_security->child_security != NULL) {
444                 tevent_req_nterror(req, NT_STATUS_INVALID_PARAMETER);
445                 return tevent_req_post(req, ev);
446         }
447
448         gensec_security->update_busy_ptr = &state->gensec_security;
449         tevent_req_set_cleanup_fn(req, gensec_update_cleanup);
450
451         subreq = state->ops->update_send(state, ev, gensec_security, in);
452         if (tevent_req_nomem(subreq, req)) {
453                 return tevent_req_post(req, ev);
454         }
455         tevent_req_set_callback(subreq, gensec_update_done, req);
456
457         return req;
458 }
459
460 static void gensec_update_cleanup(struct tevent_req *req,
461                                   enum tevent_req_state req_state)
462 {
463         struct gensec_update_state *state =
464                 tevent_req_data(req,
465                 struct gensec_update_state);
466
467         if (state->gensec_security == NULL) {
468                 return;
469         }
470
471         if (state->gensec_security->update_busy_ptr == &state->gensec_security) {
472                 state->gensec_security->update_busy_ptr = NULL;
473         }
474
475         state->gensec_security = NULL;
476 }
477
478 static void gensec_update_done(struct tevent_req *subreq)
479 {
480         struct tevent_req *req =
481                 tevent_req_callback_data(subreq,
482                 struct tevent_req);
483         struct gensec_update_state *state =
484                 tevent_req_data(req,
485                 struct gensec_update_state);
486         NTSTATUS status;
487
488         status = state->ops->update_recv(subreq, state, &state->out);
489         TALLOC_FREE(subreq);
490         state->status = status;
491         if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
492                 tevent_req_done(req);
493                 return;
494         }
495         if (tevent_req_nterror(req, status)) {
496                 return;
497         }
498
499         /*
500          * Because callers using the
501          * gensec_start_mech_by_authtype() never call
502          * gensec_want_feature(), it isn't sensible for them
503          * to have to call gensec_have_feature() manually, and
504          * these are not points of negotiation, but are
505          * asserted by the client
506          */
507         status = gensec_verify_features(state->gensec_security);
508         if (tevent_req_nterror(req, status)) {
509                 return;
510         }
511
512         tevent_req_done(req);
513 }
514
515 /**
516  * Next state function for the GENSEC state machine
517  *
518  * @param req request state
519  * @param out_mem_ctx The TALLOC_CTX for *out to be allocated on
520  * @param out The reply, as an talloc()ed DATA_BLOB, on *out_mem_ctx
521  * @return Error, MORE_PROCESSING_REQUIRED if a reply is sent,
522  *                or NT_STATUS_OK if the user is authenticated.
523  */
524 _PUBLIC_ NTSTATUS gensec_update_recv(struct tevent_req *req,
525                                      TALLOC_CTX *out_mem_ctx,
526                                      DATA_BLOB *out)
527 {
528         struct gensec_update_state *state =
529                 tevent_req_data(req, struct gensec_update_state);
530         NTSTATUS status;
531
532         *out = data_blob_null;
533
534         if (tevent_req_is_nterror(req, &status)) {
535                 tevent_req_received(req);
536                 return status;
537         }
538
539         *out = state->out;
540         talloc_steal(out_mem_ctx, out->data);
541         status = state->status;
542         tevent_req_received(req);
543         return status;
544 }
545
546 /**
547  * Set the requirement for a certain feature on the connection
548  *
549  */
550
551 _PUBLIC_ void gensec_want_feature(struct gensec_security *gensec_security,
552                          uint32_t feature)
553 {
554         if (!gensec_security->ops || !gensec_security->ops->want_feature) {
555                 gensec_security->want_features |= feature;
556                 return;
557         }
558         gensec_security->ops->want_feature(gensec_security, feature);
559 }
560
561 /**
562  * Check the requirement for a certain feature on the connection
563  *
564  */
565
566 _PUBLIC_ bool gensec_have_feature(struct gensec_security *gensec_security,
567                          uint32_t feature)
568 {
569         if (!gensec_security->ops || !gensec_security->ops->have_feature) {
570                 return false;
571         }
572
573         /* We might 'have' features that we don't 'want', because the
574          * other end demanded them, or we can't neotiate them off */
575         return gensec_security->ops->have_feature(gensec_security, feature);
576 }
577
578 _PUBLIC_ NTTIME gensec_expire_time(struct gensec_security *gensec_security)
579 {
580         if (!gensec_security->ops->expire_time) {
581                 return GENSEC_EXPIRE_TIME_INFINITY;
582         }
583
584         return gensec_security->ops->expire_time(gensec_security);
585 }
586 /**
587  * Return the credentials structure associated with a GENSEC context
588  *
589  */
590
591 _PUBLIC_ struct cli_credentials *gensec_get_credentials(struct gensec_security *gensec_security)
592 {
593         if (!gensec_security) {
594                 return NULL;
595         }
596         return gensec_security->credentials;
597 }
598
599 /**
600  * Set the target service (such as 'http' or 'host') on a GENSEC context - ensures it is talloc()ed
601  *
602  * This is used for Kerberos service principal name resolution.
603  */
604
605 _PUBLIC_ NTSTATUS gensec_set_target_service(struct gensec_security *gensec_security, const char *service)
606 {
607         gensec_security->target.service = talloc_strdup(gensec_security, service);
608         if (!gensec_security->target.service) {
609                 return NT_STATUS_NO_MEMORY;
610         }
611         return NT_STATUS_OK;
612 }
613
614 _PUBLIC_ const char *gensec_get_target_service(struct gensec_security *gensec_security)
615 {
616         if (gensec_security->target.service) {
617                 return gensec_security->target.service;
618         }
619
620         return "host";
621 }
622
623 /**
624  * Set the target service (such as 'samr') on an GENSEC context - ensures it is talloc()ed.
625  *
626  * This is not the Kerberos service principal, instead this is a
627  * constant value that can be logged as part of authentication and
628  * authorization logging
629  */
630 _PUBLIC_ NTSTATUS gensec_set_target_service_description(struct gensec_security *gensec_security,
631                                                         const char *service)
632 {
633         gensec_security->target.service_description = talloc_strdup(gensec_security, service);
634         if (!gensec_security->target.service_description) {
635                 return NT_STATUS_NO_MEMORY;
636         }
637         return NT_STATUS_OK;
638 }
639
640 _PUBLIC_ const char *gensec_get_target_service_description(struct gensec_security *gensec_security)
641 {
642         if (gensec_security->target.service_description) {
643                 return gensec_security->target.service_description;
644         } else if (gensec_security->target.service) {
645                 return gensec_security->target.service;
646         }
647
648         return NULL;
649 }
650
651 /**
652  * Set the target hostname (suitable for kerberos resolutation) on a GENSEC context - ensures it is talloc()ed
653  *
654  */
655
656 _PUBLIC_ NTSTATUS gensec_set_target_hostname(struct gensec_security *gensec_security, const char *hostname)
657 {
658         gensec_security->target.hostname = talloc_strdup(gensec_security, hostname);
659         if (hostname && !gensec_security->target.hostname) {
660                 return NT_STATUS_NO_MEMORY;
661         }
662         return NT_STATUS_OK;
663 }
664
665 _PUBLIC_ const char *gensec_get_target_hostname(struct gensec_security *gensec_security)
666 {
667         /* We allow the target hostname to be overridden for testing purposes */
668         if (gensec_security->settings->target_hostname) {
669                 return gensec_security->settings->target_hostname;
670         }
671
672         if (gensec_security->target.hostname) {
673                 return gensec_security->target.hostname;
674         }
675
676         /* We could add use the 'set sockaddr' call, and do a reverse
677          * lookup, but this would be both insecure (compromising the
678          * way kerberos works) and add DNS timeouts */
679         return NULL;
680 }
681
682 /**
683  * Set (and copy) local and peer socket addresses onto a socket
684  * context on the GENSEC context.
685  *
686  * This is so that kerberos can include these addresses in
687  * cryptographic tokens, to avoid certain attacks.
688  */
689
690 /**
691  * @brief Set the local gensec address.
692  *
693  * @param  gensec_security   The gensec security context to use.
694  *
695  * @param  remote       The local address to set.
696  *
697  * @return              On success NT_STATUS_OK is returned or an NT_STATUS
698  *                      error.
699  */
700 _PUBLIC_ NTSTATUS gensec_set_local_address(struct gensec_security *gensec_security,
701                 const struct tsocket_address *local)
702 {
703         TALLOC_FREE(gensec_security->local_addr);
704
705         if (local == NULL) {
706                 return NT_STATUS_OK;
707         }
708
709         gensec_security->local_addr = tsocket_address_copy(local, gensec_security);
710         if (gensec_security->local_addr == NULL) {
711                 return NT_STATUS_NO_MEMORY;
712         }
713
714         return NT_STATUS_OK;
715 }
716
717 /**
718  * @brief Set the remote gensec address.
719  *
720  * @param  gensec_security   The gensec security context to use.
721  *
722  * @param  remote       The remote address to set.
723  *
724  * @return              On success NT_STATUS_OK is returned or an NT_STATUS
725  *                      error.
726  */
727 _PUBLIC_ NTSTATUS gensec_set_remote_address(struct gensec_security *gensec_security,
728                 const struct tsocket_address *remote)
729 {
730         TALLOC_FREE(gensec_security->remote_addr);
731
732         if (remote == NULL) {
733                 return NT_STATUS_OK;
734         }
735
736         gensec_security->remote_addr = tsocket_address_copy(remote, gensec_security);
737         if (gensec_security->remote_addr == NULL) {
738                 return NT_STATUS_NO_MEMORY;
739         }
740
741         return NT_STATUS_OK;
742 }
743
744 /**
745  * @brief Get the local address from a gensec security context.
746  *
747  * @param  gensec_security   The security context to get the address from.
748  *
749  * @return              The address as tsocket_address which could be NULL if
750  *                      no address is set.
751  */
752 _PUBLIC_ const struct tsocket_address *gensec_get_local_address(struct gensec_security *gensec_security)
753 {
754         if (gensec_security == NULL) {
755                 return NULL;
756         }
757         return gensec_security->local_addr;
758 }
759
760 /**
761  * @brief Get the remote address from a gensec security context.
762  *
763  * @param  gensec_security   The security context to get the address from.
764  *
765  * @return              The address as tsocket_address which could be NULL if
766  *                      no address is set.
767  */
768 _PUBLIC_ const struct tsocket_address *gensec_get_remote_address(struct gensec_security *gensec_security)
769 {
770         if (gensec_security == NULL) {
771                 return NULL;
772         }
773         return gensec_security->remote_addr;
774 }
775
776 /**
777  * Set the target principal (assuming it it known, say from the SPNEGO reply)
778  *  - ensures it is talloc()ed
779  *
780  */
781
782 _PUBLIC_ NTSTATUS gensec_set_target_principal(struct gensec_security *gensec_security, const char *principal)
783 {
784         gensec_security->target.principal = talloc_strdup(gensec_security, principal);
785         if (!gensec_security->target.principal) {
786                 return NT_STATUS_NO_MEMORY;
787         }
788         return NT_STATUS_OK;
789 }
790
791 _PUBLIC_ const char *gensec_get_target_principal(struct gensec_security *gensec_security)
792 {
793         if (gensec_security->target.principal) {
794                 return gensec_security->target.principal;
795         }
796
797         return NULL;
798 }