-
Notifications
You must be signed in to change notification settings - Fork 364
/
do_tgs_req.c
1269 lines (1144 loc) · 48.3 KB
/
do_tgs_req.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/* -*- mode: c; c-basic-offset: 4; indent-tabs-mode: nil -*- */
/*
* kdc/do_tgs_req.c
*
* Copyright 1990,1991,2001,2007,2008,2009 by the Massachusetts Institute of Technology.
* All Rights Reserved.
*
* Export of this software from the United States of America may
* require a specific license from the United States Government.
* It is the responsibility of any person or organization contemplating
* export to obtain such a license before exporting.
*
* WITHIN THAT CONSTRAINT, permission to use, copy, modify, and
* distribute this software and its documentation for any purpose and
* without fee is hereby granted, provided that the above copyright
* notice appear in all copies and that both that copyright notice and
* this permission notice appear in supporting documentation, and that
* the name of M.I.T. not be used in advertising or publicity pertaining
* to distribution of the software without specific, written prior
* permission. Furthermore if you modify this software you must label
* your software as modified software and not distribute it in such a
* fashion that it might be confused with the original M.I.T. software.
* M.I.T. makes no representations about the suitability of
* this software for any purpose. It is provided "as is" without express
* or implied warranty.
*
*
* KDC Routines to deal with TGS_REQ's
*/
/*
* Copyright (c) 2006-2008, Novell, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * The copyright holder's name is not used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*/
#include "k5-int.h"
#include <syslog.h>
#ifdef HAVE_NETINET_IN_H
#include <sys/types.h>
#include <netinet/in.h>
#ifndef hpux
#include <arpa/inet.h>
#endif
#endif
#include "kdc_util.h"
#include "policy.h"
#include "extern.h"
#include "adm_proto.h"
#include <ctype.h>
static void
find_alternate_tgs(krb5_kdc_req *,krb5_db_entry *,
krb5_boolean *,int *);
static krb5_error_code
prepare_error_tgs(struct kdc_request_state *, krb5_kdc_req *,krb5_ticket *,int,
krb5_principal,krb5_data **,const char *, krb5_data *);
static krb5_int32
prep_reprocess_req(krb5_kdc_req *,krb5_principal *);
/*ARGSUSED*/
krb5_error_code
process_tgs_req(krb5_data *pkt, const krb5_fulladdr *from,
krb5_data **response)
{
krb5_keyblock * subkey = 0;
krb5_keyblock * tgskey = 0;
krb5_kdc_req *request = 0;
krb5_db_entry server;
krb5_kdc_rep reply;
krb5_enc_kdc_rep_part reply_encpart;
krb5_ticket ticket_reply, *header_ticket = 0;
int st_idx = 0;
krb5_enc_tkt_part enc_tkt_reply;
krb5_transited enc_tkt_transited;
int newtransited = 0;
krb5_error_code retval = 0;
krb5_keyblock encrypting_key;
int nprincs = 0;
krb5_boolean more;
krb5_timestamp kdc_time, authtime = 0;
krb5_keyblock session_key;
krb5_timestamp rtime;
krb5_keyblock *reply_key = NULL;
krb5_keyblock *mkey_ptr;
krb5_key_data *server_key;
char *cname = 0, *sname = 0, *altcname = 0;
krb5_last_req_entry *nolrarray[2], nolrentry;
krb5_enctype useenctype;
int errcode, errcode2;
register int i;
int firstpass = 1;
const char *status = 0;
krb5_enc_tkt_part *header_enc_tkt = NULL; /* TGT */
krb5_enc_tkt_part *subject_tkt = NULL; /* TGT or evidence ticket */
krb5_db_entry client, krbtgt;
int c_nprincs = 0, k_nprincs = 0;
krb5_pa_s4u_x509_user *s4u_x509_user = NULL; /* protocol transition request */
krb5_authdata **kdc_issued_auth_data = NULL; /* auth data issued by KDC */
unsigned int c_flags = 0, s_flags = 0; /* client/server KDB flags */
char *s4u_name = NULL;
krb5_boolean is_referral, db_ref_done = FALSE;
const char *emsg = NULL;
krb5_data *tgs_1 =NULL, *server_1 = NULL;
krb5_principal krbtgt_princ;
krb5_kvno ticket_kvno = 0;
struct kdc_request_state *state = NULL;
krb5_pa_data *pa_tgs_req; /*points into request*/
krb5_data scratch;
krb5_data e_data = empty_data(); /* backend-provided error data */
reply.padata = 0; /* For cleanup handler */
reply_encpart.enc_padata = 0;
e_data.data = NULL;
session_key.contents = NULL;
retval = decode_krb5_tgs_req(pkt, &request);
if (retval)
return retval;
if (request->msg_type != KRB5_TGS_REQ)
return KRB5_BADMSGTYPE;
/*
* setup_server_realm() sets up the global realm-specific data pointer.
*/
if ((retval = setup_server_realm(request->server))) {
krb5_free_kdc_req(kdc_context, request);
return retval;
}
errcode = kdc_process_tgs_req(request, from, pkt, &header_ticket,
&krbtgt, &k_nprincs, &tgskey,
&subkey, &pa_tgs_req);
if (header_ticket && header_ticket->enc_part2 &&
(errcode2 = krb5_unparse_name(kdc_context,
header_ticket->enc_part2->client,
&cname))) {
status = "UNPARSING CLIENT";
errcode = errcode2;
goto cleanup;
}
limit_string(cname);
if (errcode) {
status = "PROCESS_TGS";
goto cleanup;
}
if (!header_ticket) {
errcode = KRB5_NO_TKT_SUPPLIED; /* XXX? */
status="UNEXPECTED NULL in header_ticket";
goto cleanup;
}
errcode = kdc_make_rstate(&state);
if (errcode !=0) {
status = "making state";
goto cleanup;
}
scratch.length = pa_tgs_req->length;
scratch.data = (char *) pa_tgs_req->contents;
errcode = kdc_find_fast(&request, &scratch, subkey,
header_ticket->enc_part2->session, state);
if (errcode !=0) {
status = "kdc_find_fast";
goto cleanup;
}
/*
* Pointer to the encrypted part of the header ticket, which may be
* replaced to point to the encrypted part of the evidence ticket
* if constrained delegation is used. This simplifies the number of
* special cases for constrained delegation.
*/
header_enc_tkt = header_ticket->enc_part2;
/*
* We've already dealt with the AP_REQ authentication, so we can
* use header_ticket freely. The encrypted part (if any) has been
* decrypted with the session key.
*/
/* XXX make sure server here has the proper realm...taken from AP_REQ
header? */
if (isflagset(request->kdc_options, KDC_OPT_CANONICALIZE)) {
setflag(c_flags, KRB5_KDB_FLAG_CANONICALIZE);
setflag(s_flags, KRB5_KDB_FLAG_CANONICALIZE);
}
db_ref_done = FALSE;
ref_tgt_again:
nprincs = 1;
if ((errcode = krb5_unparse_name(kdc_context, request->server, &sname))) {
status = "UNPARSING SERVER";
goto cleanup;
}
limit_string(sname);
errcode = krb5_db_get_principal_ext(kdc_context,
request->server,
s_flags,
&server,
&nprincs,
&more);
if (errcode) {
status = "LOOKING_UP_SERVER";
nprincs = 0;
goto cleanup;
}
tgt_again:
if (more) {
status = "NON_UNIQUE_PRINCIPAL";
errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
goto cleanup;
} else if (nprincs != 1) {
/*
* might be a request for a TGT for some other realm; we
* should do our best to find such a TGS in this db
*/
if (firstpass ) {
if ( krb5_is_tgs_principal(request->server) == TRUE) {
/* Principal is a name of krb ticket service */
if (krb5_princ_size(kdc_context, request->server) == 2) {
server_1 = krb5_princ_component(kdc_context,
request->server, 1);
tgs_1 = krb5_princ_component(kdc_context, tgs_server, 1);
if (!tgs_1 || !data_eq(*server_1, *tgs_1)) {
krb5_db_free_principal(kdc_context, &server, nprincs);
find_alternate_tgs(request, &server, &more, &nprincs);
firstpass = 0;
goto tgt_again;
}
}
krb5_db_free_principal(kdc_context, &server, nprincs);
status = "UNKNOWN_SERVER";
errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto cleanup;
} else if ( db_ref_done == FALSE) {
retval = prep_reprocess_req(request, &krbtgt_princ);
if (!retval) {
krb5_free_principal(kdc_context, request->server);
retval = krb5_copy_principal(kdc_context, krbtgt_princ,
&(request->server));
if (!retval) {
db_ref_done = TRUE;
if (sname != NULL)
free(sname);
goto ref_tgt_again;
}
}
}
}
krb5_db_free_principal(kdc_context, &server, nprincs);
status = "UNKNOWN_SERVER";
errcode = KRB5KDC_ERR_S_PRINCIPAL_UNKNOWN;
goto cleanup;
}
if ((errcode = krb5_timeofday(kdc_context, &kdc_time))) {
status = "TIME_OF_DAY";
goto cleanup;
}
if ((retval = validate_tgs_request(request, server, header_ticket,
kdc_time, &status, &e_data))) {
if (!status)
status = "UNKNOWN_REASON";
errcode = retval + ERROR_TABLE_BASE_krb5;
goto cleanup;
}
if (!is_local_principal(header_enc_tkt->client))
setflag(c_flags, KRB5_KDB_FLAG_CROSS_REALM);
is_referral = krb5_is_tgs_principal(server.princ) &&
!krb5_principal_compare(kdc_context, tgs_server, server.princ);
/* Check for protocol transition */
errcode = kdc_process_s4u2self_req(kdc_context,
request,
header_enc_tkt->client,
&server,
subkey,
header_enc_tkt->session,
kdc_time,
&s4u_x509_user,
&client,
&c_nprincs,
&status);
if (errcode)
goto cleanup;
if (s4u_x509_user != NULL)
setflag(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION);
/*
* We pick the session keytype here....
*
* Some special care needs to be taken in the user-to-user
* case, since we don't know what keytypes the application server
* which is doing user-to-user authentication can support. We
* know that it at least must be able to support the encryption
* type of the session key in the TGT, since otherwise it won't be
* able to decrypt the U2U ticket! So we use that in preference
* to anything else.
*/
useenctype = 0;
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY |
KDC_OPT_CNAME_IN_ADDL_TKT)) {
krb5_keyblock * st_sealing_key;
krb5_kvno st_srv_kvno;
krb5_enctype etype;
krb5_db_entry st_client;
int st_nprincs = 0;
/*
* Get the key for the second ticket, and decrypt it.
*/
if ((errcode = kdc_get_server_key(request->second_ticket[st_idx],
c_flags,
TRUE, /* match_enctype */
&st_client,
&st_nprincs,
&st_sealing_key,
&st_srv_kvno))) {
status = "2ND_TKT_SERVER";
goto cleanup;
}
errcode = krb5_decrypt_tkt_part(kdc_context, st_sealing_key,
request->second_ticket[st_idx]);
krb5_free_keyblock(kdc_context, st_sealing_key);
if (errcode) {
status = "2ND_TKT_DECRYPT";
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
goto cleanup;
}
etype = request->second_ticket[st_idx]->enc_part2->session->enctype;
if (!krb5_c_valid_enctype(etype)) {
status = "BAD_ETYPE_IN_2ND_TKT";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
goto cleanup;
}
for (i = 0; i < request->nktypes; i++) {
if (request->ktype[i] == etype) {
useenctype = etype;
break;
}
}
if (isflagset(request->kdc_options, KDC_OPT_CNAME_IN_ADDL_TKT)) {
/* Do constrained delegation protocol and authorization checks */
errcode = kdc_process_s4u2proxy_req(kdc_context,
request,
request->second_ticket[st_idx]->enc_part2,
&st_client,
header_ticket->enc_part2->client,
request->server,
&status);
if (errcode)
goto cleanup;
setflag(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION);
assert(krb5_is_tgs_principal(header_ticket->server));
assert(c_nprincs == 0); /* assured by kdc_process_s4u2self_req() */
client = st_client;
c_nprincs = st_nprincs;
} else {
/* "client" is not used for user2user */
krb5_db_free_principal(kdc_context, &st_client, st_nprincs);
}
}
/*
* Select the keytype for the ticket session key.
*/
if ((useenctype == 0) &&
(useenctype = select_session_keytype(kdc_context, &server,
request->nktypes,
request->ktype)) == 0) {
/* unsupported ktype */
status = "BAD_ENCRYPTION_TYPE";
errcode = KRB5KDC_ERR_ETYPE_NOSUPP;
goto cleanup;
}
errcode = krb5_c_make_random_key(kdc_context, useenctype, &session_key);
if (errcode) {
/* random key failed */
status = "RANDOM_KEY_FAILED";
goto cleanup;
}
/*
* subject_tkt will refer to the evidence ticket (for constrained
* delegation) or the TGT. The distinction from header_enc_tkt is
* necessary because the TGS signature only protects some fields:
* the others could be forged by a malicious server.
*/
if (isflagset(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION))
subject_tkt = request->second_ticket[st_idx]->enc_part2;
else
subject_tkt = header_enc_tkt;
authtime = subject_tkt->times.authtime;
if (is_referral)
ticket_reply.server = server.princ;
else
ticket_reply.server = request->server; /* XXX careful for realm... */
enc_tkt_reply.flags = 0;
enc_tkt_reply.times.starttime = 0;
if (isflagset(server.attributes, KRB5_KDB_OK_AS_DELEGATE))
setflag(enc_tkt_reply.flags, TKT_FLG_OK_AS_DELEGATE);
/*
* Fix header_ticket's starttime; if it's zero, fill in the
* authtime's value.
*/
if (!(header_enc_tkt->times.starttime))
header_enc_tkt->times.starttime = authtime;
setflag(enc_tkt_reply.flags, TKT_FLG_ENC_PA_REP);
/* don't use new addresses unless forwarded, see below */
enc_tkt_reply.caddrs = header_enc_tkt->caddrs;
/* noaddrarray[0] = 0; */
reply_encpart.caddrs = 0;/* optional...don't put it in */
reply_encpart.enc_padata = NULL;
/*
* It should be noted that local policy may affect the
* processing of any of these flags. For example, some
* realms may refuse to issue renewable tickets
*/
if (isflagset(request->kdc_options, KDC_OPT_FORWARDABLE)) {
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION)) {
/*
* If S4U2Self principal is not forwardable, then mark ticket as
* unforwardable. This behaviour matches Windows, but it is
* different to the MIT AS-REQ path, which returns an error
* (KDC_ERR_POLICY) if forwardable tickets cannot be issued.
*
* Consider this block the S4U2Self equivalent to
* validate_forwardable().
*/
if (c_nprincs &&
isflagset(client.attributes, KRB5_KDB_DISALLOW_FORWARDABLE))
clear(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
/*
* Forwardable flag is propagated along referral path.
*/
else if (!isflagset(header_enc_tkt->flags, TKT_FLG_FORWARDABLE))
clear(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
/*
* OK_TO_AUTH_AS_DELEGATE must be set on the service requesting
* S4U2Self in order for forwardable tickets to be returned.
*/
else if (!is_referral &&
!isflagset(server.attributes,
KRB5_KDB_OK_TO_AUTH_AS_DELEGATE))
clear(enc_tkt_reply.flags, TKT_FLG_FORWARDABLE);
}
}
if (isflagset(request->kdc_options, KDC_OPT_FORWARDED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(header_enc_tkt->flags, TKT_FLG_FORWARDED))
setflag(enc_tkt_reply.flags, TKT_FLG_FORWARDED);
if (isflagset(request->kdc_options, KDC_OPT_PROXIABLE))
setflag(enc_tkt_reply.flags, TKT_FLG_PROXIABLE);
if (isflagset(request->kdc_options, KDC_OPT_PROXY)) {
setflag(enc_tkt_reply.flags, TKT_FLG_PROXY);
/* include new addresses in ticket & reply */
enc_tkt_reply.caddrs = request->addresses;
reply_encpart.caddrs = request->addresses;
}
if (isflagset(request->kdc_options, KDC_OPT_ALLOW_POSTDATE))
setflag(enc_tkt_reply.flags, TKT_FLG_MAY_POSTDATE);
if (isflagset(request->kdc_options, KDC_OPT_POSTDATED)) {
setflag(enc_tkt_reply.flags, TKT_FLG_POSTDATED);
setflag(enc_tkt_reply.flags, TKT_FLG_INVALID);
enc_tkt_reply.times.starttime = request->from;
} else
enc_tkt_reply.times.starttime = kdc_time;
if (isflagset(request->kdc_options, KDC_OPT_VALIDATE)) {
assert(isflagset(c_flags, KRB5_KDB_FLAGS_S4U) == 0);
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
clear(enc_tkt_reply.flags, TKT_FLG_INVALID);
}
if (isflagset(request->kdc_options, KDC_OPT_RENEW)) {
krb5_deltat old_life;
assert(isflagset(c_flags, KRB5_KDB_FLAGS_S4U) == 0);
/* BEWARE of allocation hanging off of ticket & enc_part2, it belongs
to the caller */
ticket_reply = *(header_ticket);
enc_tkt_reply = *(header_ticket->enc_part2);
old_life = enc_tkt_reply.times.endtime - enc_tkt_reply.times.starttime;
enc_tkt_reply.times.starttime = kdc_time;
enc_tkt_reply.times.endtime =
min(header_ticket->enc_part2->times.renew_till,
kdc_time + old_life);
} else {
/* not a renew request */
enc_tkt_reply.times.starttime = kdc_time;
kdc_get_ticket_endtime(kdc_context,
enc_tkt_reply.times.starttime,
header_enc_tkt->times.endtime,
request->till,
&client,
&server,
&enc_tkt_reply.times.endtime);
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE_OK) &&
(enc_tkt_reply.times.endtime < request->till) &&
isflagset(header_enc_tkt->flags, TKT_FLG_RENEWABLE)) {
setflag(request->kdc_options, KDC_OPT_RENEWABLE);
request->rtime =
min(request->till, header_enc_tkt->times.renew_till);
}
}
rtime = (request->rtime == 0) ? kdc_infinity : request->rtime;
if (isflagset(request->kdc_options, KDC_OPT_RENEWABLE)) {
/* already checked above in policy check to reject request for a
renewable ticket using a non-renewable ticket */
setflag(enc_tkt_reply.flags, TKT_FLG_RENEWABLE);
enc_tkt_reply.times.renew_till =
min(rtime,
min(header_enc_tkt->times.renew_till,
enc_tkt_reply.times.starttime +
min(server.max_renewable_life,
max_renewable_life_for_realm)));
} else {
enc_tkt_reply.times.renew_till = 0;
}
if (isflagset(header_enc_tkt->flags, TKT_FLG_ANONYMOUS))
setflag(enc_tkt_reply.flags, TKT_FLG_ANONYMOUS);
/*
* Set authtime to be the same as header or evidence ticket's
*/
enc_tkt_reply.times.authtime = authtime;
/*
* Propagate the preauthentication flags through to the returned ticket.
*/
if (isflagset(header_enc_tkt->flags, TKT_FLG_PRE_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_PRE_AUTH);
if (isflagset(header_enc_tkt->flags, TKT_FLG_HW_AUTH))
setflag(enc_tkt_reply.flags, TKT_FLG_HW_AUTH);
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION)) {
errcode = krb5_unparse_name(kdc_context, s4u_x509_user->user_id.user,
&s4u_name);
} else if (isflagset(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION)) {
errcode = krb5_unparse_name(kdc_context, subject_tkt->client,
&s4u_name);
} else {
errcode = 0;
}
if (errcode) {
status = "UNPARSING S4U CLIENT";
goto cleanup;
}
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
krb5_enc_tkt_part *t2enc = request->second_ticket[st_idx]->enc_part2;
encrypting_key = *(t2enc->session);
} else {
/*
* Find the server key
*/
if ((errcode = krb5_dbe_find_enctype(kdc_context, &server,
-1, /* ignore keytype */
-1, /* Ignore salttype */
0, /* Get highest kvno */
&server_key))) {
status = "FINDING_SERVER_KEY";
goto cleanup;
}
if ((errcode = krb5_dbe_find_mkey(kdc_context, master_keylist, &server,
&mkey_ptr))) {
krb5_keylist_node *tmp_mkey_list;
/* try refreshing master key list */
/* XXX it would nice if we had the mkvno here for optimization */
if (krb5_db_fetch_mkey_list(kdc_context, master_princ,
&master_keyblock, 0, &tmp_mkey_list) == 0) {
krb5_dbe_free_key_list(kdc_context, master_keylist);
master_keylist = tmp_mkey_list;
if ((errcode = krb5_dbe_find_mkey(kdc_context, master_keylist,
&server, &mkey_ptr))) {
status = "FINDING_MASTER_KEY";
goto cleanup;
}
} else {
status = "FINDING_MASTER_KEY";
goto cleanup;
}
}
/*
* Convert server.key into a real key
* (it may be encrypted in the database)
*/
if ((errcode = krb5_dbekd_decrypt_key_data(kdc_context,
mkey_ptr,
server_key, &encrypting_key,
NULL))) {
status = "DECRYPT_SERVER_KEY";
goto cleanup;
}
}
if (isflagset(c_flags, KRB5_KDB_FLAG_CONSTRAINED_DELEGATION)) {
/*
* Don't allow authorization data to be disabled if constrained
* delegation is requested. We don't want to deny the server
* the ability to validate that delegation was used.
*/
clear(server.attributes, KRB5_KDB_NO_AUTH_DATA_REQUIRED);
}
if (isflagset(server.attributes, KRB5_KDB_NO_AUTH_DATA_REQUIRED) == 0) {
/*
* If we are not doing protocol transition/constrained delegation
* try to lookup the client principal so plugins can add additional
* authorization information.
*
* Always validate authorization data for constrained delegation
* because we must validate the KDC signatures.
*/
if (!isflagset(c_flags, KRB5_KDB_FLAGS_S4U)) {
/* Generate authorization data so we can include it in ticket */
setflag(c_flags, KRB5_KDB_FLAG_INCLUDE_PAC);
/* Map principals from foreign (possibly non-AD) realms */
setflag(c_flags, KRB5_KDB_FLAG_MAP_PRINCIPALS);
assert(c_nprincs == 0); /* should not have been looked up already */
c_nprincs = 1;
errcode = krb5_db_get_principal_ext(kdc_context,
subject_tkt->client,
c_flags,
&client,
&c_nprincs,
&more);
/*
* We can ignore errors because the principal may be a
* valid cross-realm principal for which we have no local
* mapping. But we do want to check that at most one entry
* was returned.
*/
if (errcode == 0 && (more || c_nprincs > 1)) {
errcode = KRB5KDC_ERR_PRINCIPAL_NOT_UNIQUE;
goto cleanup;
} else if (errcode) {
c_nprincs = 0;
}
}
}
enc_tkt_reply.authorization_data = NULL;
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION) &&
!isflagset(c_flags, KRB5_KDB_FLAG_CROSS_REALM))
enc_tkt_reply.client = s4u_x509_user->user_id.user;
else
enc_tkt_reply.client = subject_tkt->client;
enc_tkt_reply.session = &session_key;
enc_tkt_reply.transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_reply.transited.tr_contents = empty_string; /* equivalent of "" */
errcode = handle_authdata(kdc_context,
c_flags,
(c_nprincs != 0) ? &client : NULL,
&server,
(k_nprincs != 0) ? &krbtgt : NULL,
subkey != NULL ? subkey :
header_ticket->enc_part2->session,
&encrypting_key, /* U2U or server key */
tgskey,
pkt,
request,
s4u_x509_user ?
s4u_x509_user->user_id.user : NULL,
subject_tkt,
&enc_tkt_reply);
if (errcode) {
krb5_klog_syslog(LOG_INFO, "TGS_REQ : handle_authdata (%d)", errcode);
status = "HANDLE_AUTHDATA";
goto cleanup;
}
/*
* Only add the realm of the presented tgt to the transited list if
* it is different than the local realm (cross-realm) and it is different
* than the realm of the client (since the realm of the client is already
* implicitly part of the transited list and should not be explicitly
* listed).
*/
/* realm compare is like strcmp, but knows how to deal with these args */
if (realm_compare(header_ticket->server, tgs_server) ||
realm_compare(header_ticket->server, enc_tkt_reply.client)) {
/* tgt issued by local realm or issued by realm of client */
enc_tkt_reply.transited = header_enc_tkt->transited;
} else {
/* tgt issued by some other realm and not the realm of the client */
/* assemble new transited field into allocated storage */
if (header_enc_tkt->transited.tr_type !=
KRB5_DOMAIN_X500_COMPRESS) {
status = "BAD_TRTYPE";
errcode = KRB5KDC_ERR_TRTYPE_NOSUPP;
goto cleanup;
}
enc_tkt_transited.tr_type = KRB5_DOMAIN_X500_COMPRESS;
enc_tkt_transited.magic = 0;
enc_tkt_transited.tr_contents.magic = 0;
enc_tkt_transited.tr_contents.data = 0;
enc_tkt_transited.tr_contents.length = 0;
enc_tkt_reply.transited = enc_tkt_transited;
if ((errcode =
add_to_transited(&header_enc_tkt->transited.tr_contents,
&enc_tkt_reply.transited.tr_contents,
header_ticket->server,
enc_tkt_reply.client,
request->server))) {
status = "ADD_TR_FAIL";
goto cleanup;
}
newtransited = 1;
}
if (isflagset(c_flags, KRB5_KDB_FLAG_CROSS_REALM)) {
errcode = validate_transit_path(kdc_context, header_enc_tkt->client,
&server,
(k_nprincs != 0) ? &krbtgt : NULL);
if (errcode) {
status = "NON_TRANSITIVE";
goto cleanup;
}
}
if (!isflagset (request->kdc_options, KDC_OPT_DISABLE_TRANSITED_CHECK)) {
unsigned int tlen;
char *tdots;
errcode = kdc_check_transited_list (kdc_context,
&enc_tkt_reply.transited.tr_contents,
krb5_princ_realm (kdc_context, header_enc_tkt->client),
krb5_princ_realm (kdc_context, request->server));
tlen = enc_tkt_reply.transited.tr_contents.length;
tdots = tlen > 125 ? "..." : "";
tlen = tlen > 125 ? 125 : tlen;
if (errcode == 0) {
setflag (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED);
} else if (errcode == KRB5KRB_AP_ERR_ILL_CR_TKT)
krb5_klog_syslog (LOG_INFO,
"bad realm transit path from '%s' to '%s' "
"via '%.*s%s'",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots);
else {
emsg = krb5_get_error_message(kdc_context, errcode);
krb5_klog_syslog (LOG_ERR,
"unexpected error checking transit from "
"'%s' to '%s' via '%.*s%s': %s",
cname ? cname : "<unknown client>",
sname ? sname : "<unknown server>",
tlen,
enc_tkt_reply.transited.tr_contents.data,
tdots, emsg);
krb5_free_error_message(kdc_context, emsg);
emsg = NULL;
}
} else
krb5_klog_syslog (LOG_INFO, "not checking transit path");
if (reject_bad_transit
&& !isflagset (enc_tkt_reply.flags, TKT_FLG_TRANSIT_POLICY_CHECKED)) {
errcode = KRB5KDC_ERR_POLICY;
status = "BAD_TRANSIT";
goto cleanup;
}
ticket_reply.enc_part2 = &enc_tkt_reply;
/*
* If we are doing user-to-user authentication, then make sure
* that the client for the second ticket matches the request
* server, and then encrypt the ticket using the session key of
* the second ticket.
*/
if (isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY)) {
/*
* Make sure the client for the second ticket matches
* requested server.
*/
krb5_enc_tkt_part *t2enc = request->second_ticket[st_idx]->enc_part2;
krb5_principal client2 = t2enc->client;
if (!krb5_principal_compare(kdc_context, request->server, client2)) {
if ((errcode = krb5_unparse_name(kdc_context, client2, &altcname)))
altcname = 0;
if (altcname != NULL)
limit_string(altcname);
errcode = KRB5KDC_ERR_SERVER_NOMATCH;
status = "2ND_TKT_MISMATCH";
goto cleanup;
}
ticket_kvno = 0;
ticket_reply.enc_part.enctype = t2enc->session->enctype;
st_idx++;
} else {
ticket_kvno = server_key->key_data_kvno;
}
errcode = krb5_encrypt_tkt_part(kdc_context, &encrypting_key,
&ticket_reply);
if (!isflagset(request->kdc_options, KDC_OPT_ENC_TKT_IN_SKEY))
krb5_free_keyblock_contents(kdc_context, &encrypting_key);
if (errcode) {
status = "TKT_ENCRYPT";
goto cleanup;
}
ticket_reply.enc_part.kvno = ticket_kvno;
/* Start assembling the response */
reply.msg_type = KRB5_TGS_REP;
if (isflagset(c_flags, KRB5_KDB_FLAG_PROTOCOL_TRANSITION) &&
find_pa_data(request->padata, KRB5_PADATA_S4U_X509_USER) != NULL) {
errcode = kdc_make_s4u2self_rep(kdc_context,
subkey,
header_ticket->enc_part2->session,
s4u_x509_user,
&reply,
&reply_encpart);
if (errcode) {
status = "KDC_RETURN_S4U2SELF_PADATA";
goto cleanup;
}
}
reply.client = enc_tkt_reply.client;
reply.enc_part.kvno = 0;/* We are using the session key */
reply.ticket = &ticket_reply;
reply_encpart.session = &session_key;
reply_encpart.nonce = request->nonce;
/* copy the time fields */
reply_encpart.times = enc_tkt_reply.times;
/* starttime is optional, and treated as authtime if not present.
so we can nuke it if it matches */
if (enc_tkt_reply.times.starttime == enc_tkt_reply.times.authtime)
enc_tkt_reply.times.starttime = 0;
nolrentry.lr_type = KRB5_LRQ_NONE;
nolrentry.value = 0;
nolrarray[0] = &nolrentry;
nolrarray[1] = 0;
reply_encpart.last_req = nolrarray; /* not available for TGS reqs */
reply_encpart.key_exp = 0;/* ditto */
reply_encpart.flags = enc_tkt_reply.flags;
reply_encpart.server = ticket_reply.server;
/* use the session key in the ticket, unless there's a subsession key
in the AP_REQ */
reply.enc_part.enctype = subkey ? subkey->enctype :
header_ticket->enc_part2->session->enctype;
errcode = kdc_fast_response_handle_padata(state, request, &reply,
subkey ? subkey->enctype : header_ticket->enc_part2->session->enctype);
if (errcode !=0 ) {
status = "Preparing FAST padata";
goto cleanup;
}
errcode =kdc_fast_handle_reply_key(state,
subkey?subkey:header_ticket->enc_part2->session, &reply_key);
if (errcode) {
status = "generating reply key";
goto cleanup;
}
errcode = return_enc_padata(kdc_context, pkt, request,
reply_key, &server, &reply_encpart,
is_referral &&
isflagset(s_flags,
KRB5_KDB_FLAG_CANONICALIZE));
if (errcode) {
status = "KDC_RETURN_ENC_PADATA";
goto cleanup;
}
errcode = krb5_encode_kdc_rep(kdc_context, KRB5_TGS_REP, &reply_encpart,
subkey ? 1 : 0,
reply_key,
&reply, response);
if (errcode) {
status = "ENCODE_KDC_REP";
} else {
status = "ISSUE";
}
memset(ticket_reply.enc_part.ciphertext.data, 0,
ticket_reply.enc_part.ciphertext.length);
free(ticket_reply.enc_part.ciphertext.data);
/* these parts are left on as a courtesy from krb5_encode_kdc_rep so we
can use them in raw form if needed. But, we don't... */
memset(reply.enc_part.ciphertext.data, 0,
reply.enc_part.ciphertext.length);
free(reply.enc_part.ciphertext.data);
cleanup:
assert(status != NULL);
if (reply_key)
krb5_free_keyblock(kdc_context, reply_key);
if (errcode)
emsg = krb5_get_error_message (kdc_context, errcode);
log_tgs_req(from, request, &reply, cname, sname, altcname, authtime,
c_flags, s4u_name, status, errcode, emsg);
if (errcode) {
krb5_free_error_message (kdc_context, emsg);
emsg = NULL;
}
if (errcode) {
int got_err = 0;
if (status == 0) {
status = krb5_get_error_message (kdc_context, errcode);
got_err = 1;
}