source: heimdal/trunk/lib/krb5/rd_req.c

Last change on this file was 1, checked in by Paul Smedley, 10 years ago

Initial commit of Heimdal 1.5.3
File size: 25.6 KB
Line 
1
2/*
3 * Copyright (c) 1997 - 2007 Kungliga Tekniska Högskolan
4 * (Royal Institute of Technology, Stockholm, Sweden).
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 *
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 *
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * 3. Neither the name of the Institute nor the names of its contributors
19 * may be used to endorse or promote products derived from this software
20 * without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
25 * ARE DISCLAIMED. IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32 * SUCH DAMAGE.
33 */
34
35#include "krb5_locl.h"
36
37static krb5_error_code
38decrypt_tkt_enc_part (krb5_context context,
39 krb5_keyblock *key,
40 EncryptedData *enc_part,
41 EncTicketPart *decr_part)
42{
43 krb5_error_code ret;
44 krb5_data plain;
45 size_t len;
46 krb5_crypto crypto;
47
48 ret = krb5_crypto_init(context, key, 0, &crypto);
49 if (ret)
50 return ret;
51 ret = krb5_decrypt_EncryptedData (context,
52 crypto,
53 KRB5_KU_TICKET,
54 enc_part,
55 &plain);
56 krb5_crypto_destroy(context, crypto);
57 if (ret)
58 return ret;
59
60 ret = decode_EncTicketPart(plain.data, plain.length, decr_part, &len);
61 if (ret)
62 krb5_set_error_message(context, ret,
63 N_("Failed to decode encrypted "
64 "ticket part", ""));
65 krb5_data_free (&plain);
66 return ret;
67}
68
69static krb5_error_code
70decrypt_authenticator (krb5_context context,
71 EncryptionKey *key,
72 EncryptedData *enc_part,
73 Authenticator *authenticator,
74 krb5_key_usage usage)
75{
76 krb5_error_code ret;
77 krb5_data plain;
78 size_t len;
79 krb5_crypto crypto;
80
81 ret = krb5_crypto_init(context, key, 0, &crypto);
82 if (ret)
83 return ret;
84 ret = krb5_decrypt_EncryptedData (context,
85 crypto,
86 usage /* KRB5_KU_AP_REQ_AUTH */,
87 enc_part,
88 &plain);
89 /* for backwards compatibility, also try the old usage */
90 if (ret && usage == KRB5_KU_TGS_REQ_AUTH)
91 ret = krb5_decrypt_EncryptedData (context,
92 crypto,
93 KRB5_KU_AP_REQ_AUTH,
94 enc_part,
95 &plain);
96 krb5_crypto_destroy(context, crypto);
97 if (ret)
98 return ret;
99
100 ret = decode_Authenticator(plain.data, plain.length,
101 authenticator, &len);
102 krb5_data_free (&plain);
103 return ret;
104}
105
106KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
107krb5_decode_ap_req(krb5_context context,
108 const krb5_data *inbuf,
109 krb5_ap_req *ap_req)
110{
111 krb5_error_code ret;
112 size_t len;
113 ret = decode_AP_REQ(inbuf->data, inbuf->length, ap_req, &len);
114 if (ret)
115 return ret;
116 if (ap_req->pvno != 5){
117 free_AP_REQ(ap_req);
118 krb5_clear_error_message (context);
119 return KRB5KRB_AP_ERR_BADVERSION;
120 }
121 if (ap_req->msg_type != krb_ap_req){
122 free_AP_REQ(ap_req);
123 krb5_clear_error_message (context);
124 return KRB5KRB_AP_ERR_MSG_TYPE;
125 }
126 if (ap_req->ticket.tkt_vno != 5){
127 free_AP_REQ(ap_req);
128 krb5_clear_error_message (context);
129 return KRB5KRB_AP_ERR_BADVERSION;
130 }
131 return 0;
132}
133
134static krb5_error_code
135check_transited(krb5_context context, Ticket *ticket, EncTicketPart *enc)
136{
137 char **realms;
138 unsigned int num_realms, n;
139 krb5_error_code ret;
140
141 /*
142 * Windows 2000 and 2003 uses this inside their TGT so it's normaly
143 * not seen by others, however, samba4 joined with a Windows AD as
144 * a Domain Controller gets exposed to this.
145 */
146 if(enc->transited.tr_type == 0 && enc->transited.contents.length == 0)
147 return 0;
148
149 if(enc->transited.tr_type != DOMAIN_X500_COMPRESS)
150 return KRB5KDC_ERR_TRTYPE_NOSUPP;
151
152 if(enc->transited.contents.length == 0)
153 return 0;
154
155 ret = krb5_domain_x500_decode(context, enc->transited.contents,
156 &realms, &num_realms,
157 enc->crealm,
158 ticket->realm);
159 if(ret)
160 return ret;
161 ret = krb5_check_transited(context, enc->crealm,
162 ticket->realm,
163 realms, num_realms, NULL);
164 for (n = 0; n < num_realms; n++)
165 free(realms[n]);
166 free(realms);
167 return ret;
168}
169
170static krb5_error_code
171find_etypelist(krb5_context context,
172 krb5_auth_context auth_context,
173 EtypeList *etypes)
174{
175 krb5_error_code ret;
176 krb5_authdata *ad;
177 krb5_authdata adIfRelevant;
178 unsigned i;
179
180 memset(&adIfRelevant, 0, sizeof(adIfRelevant));
181
182 etypes->len = 0;
183 etypes->val = NULL;
184
185 ad = auth_context->authenticator->authorization_data;
186 if (ad == NULL)
187 return 0;
188
189 for (i = 0; i < ad->len; i++) {
190 if (ad->val[i].ad_type == KRB5_AUTHDATA_IF_RELEVANT) {
191 ret = decode_AD_IF_RELEVANT(ad->val[i].ad_data.data,
192 ad->val[i].ad_data.length,
193 &adIfRelevant,
194 NULL);
195 if (ret)
196 return ret;
197
198 if (adIfRelevant.len == 1 &&
199 adIfRelevant.val[0].ad_type ==
200 KRB5_AUTHDATA_GSS_API_ETYPE_NEGOTIATION) {
201 break;
202 }
203 free_AD_IF_RELEVANT(&adIfRelevant);
204 adIfRelevant.len = 0;
205 }
206 }
207
208 if (adIfRelevant.len == 0)
209 return 0;
210
211 ret = decode_EtypeList(adIfRelevant.val[0].ad_data.data,
212 adIfRelevant.val[0].ad_data.length,
213 etypes,
214 NULL);
215 if (ret)
216 krb5_clear_error_message(context);
217
218 free_AD_IF_RELEVANT(&adIfRelevant);
219
220 return ret;
221}
222
223KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
224krb5_decrypt_ticket(krb5_context context,
225 Ticket *ticket,
226 krb5_keyblock *key,
227 EncTicketPart *out,
228 krb5_flags flags)
229{
230 EncTicketPart t;
231 krb5_error_code ret;
232 ret = decrypt_tkt_enc_part (context, key, &ticket->enc_part, &t);
233 if (ret)
234 return ret;
235
236 {
237 krb5_timestamp now;
238 time_t start = t.authtime;
239
240 krb5_timeofday (context, &now);
241 if(t.starttime)
242 start = *t.starttime;
243 if(start - now > context->max_skew
244 || (t.flags.invalid
245 && !(flags & KRB5_VERIFY_AP_REQ_IGNORE_INVALID))) {
246 free_EncTicketPart(&t);
247 krb5_clear_error_message (context);
248 return KRB5KRB_AP_ERR_TKT_NYV;
249 }
250 if(now - t.endtime > context->max_skew) {
251 free_EncTicketPart(&t);
252 krb5_clear_error_message (context);
253 return KRB5KRB_AP_ERR_TKT_EXPIRED;
254 }
255
256 if(!t.flags.transited_policy_checked) {
257 ret = check_transited(context, ticket, &t);
258 if(ret) {
259 free_EncTicketPart(&t);
260 return ret;
261 }
262 }
263 }
264
265 if(out)
266 *out = t;
267 else
268 free_EncTicketPart(&t);
269 return 0;
270}
271
272KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
273krb5_verify_authenticator_checksum(krb5_context context,
274 krb5_auth_context ac,
275 void *data,
276 size_t len)
277{
278 krb5_error_code ret;
279 krb5_keyblock *key;
280 krb5_authenticator authenticator;
281 krb5_crypto crypto;
282
283 ret = krb5_auth_con_getauthenticator (context,
284 ac,
285 &authenticator);
286 if(ret)
287 return ret;
288 if(authenticator->cksum == NULL) {
289 krb5_free_authenticator(context, &authenticator);
290 return -17;
291 }
292 ret = krb5_auth_con_getkey(context, ac, &key);
293 if(ret) {
294 krb5_free_authenticator(context, &authenticator);
295 return ret;
296 }
297 ret = krb5_crypto_init(context, key, 0, &crypto);
298 if(ret)
299 goto out;
300 ret = krb5_verify_checksum (context,
301 crypto,
302 KRB5_KU_AP_REQ_AUTH_CKSUM,
303 data,
304 len,
305 authenticator->cksum);
306 krb5_crypto_destroy(context, crypto);
307out:
308 krb5_free_authenticator(context, &authenticator);
309 krb5_free_keyblock(context, key);
310 return ret;
311}
312
313
314KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
315krb5_verify_ap_req(krb5_context context,
316 krb5_auth_context *auth_context,
317 krb5_ap_req *ap_req,
318 krb5_const_principal server,
319 krb5_keyblock *keyblock,
320 krb5_flags flags,
321 krb5_flags *ap_req_options,
322 krb5_ticket **ticket)
323{
324 return krb5_verify_ap_req2 (context,
325 auth_context,
326 ap_req,
327 server,
328 keyblock,
329 flags,
330 ap_req_options,
331 ticket,
332 KRB5_KU_AP_REQ_AUTH);
333}
334
335KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
336krb5_verify_ap_req2(krb5_context context,
337 krb5_auth_context *auth_context,
338 krb5_ap_req *ap_req,
339 krb5_const_principal server,
340 krb5_keyblock *keyblock,
341 krb5_flags flags,
342 krb5_flags *ap_req_options,
343 krb5_ticket **ticket,
344 krb5_key_usage usage)
345{
346 krb5_ticket *t;
347 krb5_auth_context ac;
348 krb5_error_code ret;
349 EtypeList etypes;
350
351 if (ticket)
352 *ticket = NULL;
353
354 if (auth_context && *auth_context) {
355 ac = *auth_context;
356 } else {
357 ret = krb5_auth_con_init (context, &ac);
358 if (ret)
359 return ret;
360 }
361
362 t = calloc(1, sizeof(*t));
363 if (t == NULL) {
364 ret = ENOMEM;
365 krb5_clear_error_message (context);
366 goto out;
367 }
368
369 if (ap_req->ap_options.use_session_key && ac->keyblock){
370 ret = krb5_decrypt_ticket(context, &ap_req->ticket,
371 ac->keyblock,
372 &t->ticket,
373 flags);
374 krb5_free_keyblock(context, ac->keyblock);
375 ac->keyblock = NULL;
376 }else
377 ret = krb5_decrypt_ticket(context, &ap_req->ticket,
378 keyblock,
379 &t->ticket,
380 flags);
381
382 if(ret)
383 goto out;
384
385 ret = _krb5_principalname2krb5_principal(context,
386 &t->server,
387 ap_req->ticket.sname,
388 ap_req->ticket.realm);
389 if (ret) goto out;
390 ret = _krb5_principalname2krb5_principal(context,
391 &t->client,
392 t->ticket.cname,
393 t->ticket.crealm);
394 if (ret) goto out;
395
396 ret = decrypt_authenticator (context,
397 &t->ticket.key,
398 &ap_req->authenticator,
399 ac->authenticator,
400 usage);
401 if (ret)
402 goto out;
403
404 {
405 krb5_principal p1, p2;
406 krb5_boolean res;
407
408 _krb5_principalname2krb5_principal(context,
409 &p1,
410 ac->authenticator->cname,
411 ac->authenticator->crealm);
412 _krb5_principalname2krb5_principal(context,
413 &p2,
414 t->ticket.cname,
415 t->ticket.crealm);
416 res = krb5_principal_compare (context, p1, p2);
417 krb5_free_principal (context, p1);
418 krb5_free_principal (context, p2);
419 if (!res) {
420 ret = KRB5KRB_AP_ERR_BADMATCH;
421 krb5_clear_error_message (context);
422 goto out;
423 }
424 }
425
426 /* check addresses */
427
428 if (t->ticket.caddr
429 && ac->remote_address
430 && !krb5_address_search (context,
431 ac->remote_address,
432 t->ticket.caddr)) {
433 ret = KRB5KRB_AP_ERR_BADADDR;
434 krb5_clear_error_message (context);
435 goto out;
436 }
437
438 /* check timestamp in authenticator */
439 {
440 krb5_timestamp now;
441
442 krb5_timeofday (context, &now);
443
444 if (abs(ac->authenticator->ctime - now) > context->max_skew) {
445 ret = KRB5KRB_AP_ERR_SKEW;
446 krb5_clear_error_message (context);
447 goto out;
448 }
449 }
450
451 if (ac->authenticator->seq_number)
452 krb5_auth_con_setremoteseqnumber(context, ac,
453 *ac->authenticator->seq_number);
454
455 /* XXX - Xor sequence numbers */
456
457 if (ac->authenticator->subkey) {
458 ret = krb5_auth_con_setremotesubkey(context, ac,
459 ac->authenticator->subkey);
460 if (ret)
461 goto out;
462 }
463
464 ret = find_etypelist(context, ac, &etypes);
465 if (ret)
466 goto out;
467
468 ac->keytype = ETYPE_NULL;
469
470 if (etypes.val) {
471 size_t i;
472
473 for (i = 0; i < etypes.len; i++) {
474 if (krb5_enctype_valid(context, etypes.val[i]) == 0) {
475 ac->keytype = etypes.val[i];
476 break;
477 }
478 }
479 }
480
481 /* save key */
482 ret = krb5_copy_keyblock(context, &t->ticket.key, &ac->keyblock);
483 if (ret) goto out;
484
485 if (ap_req_options) {
486 *ap_req_options = 0;
487 if (ac->keytype != ETYPE_NULL)
488 *ap_req_options |= AP_OPTS_USE_SUBKEY;
489 if (ap_req->ap_options.use_session_key)
490 *ap_req_options |= AP_OPTS_USE_SESSION_KEY;
491 if (ap_req->ap_options.mutual_required)
492 *ap_req_options |= AP_OPTS_MUTUAL_REQUIRED;
493 }
494
495 if(ticket)
496 *ticket = t;
497 else
498 krb5_free_ticket (context, t);
499 if (auth_context) {
500 if (*auth_context == NULL)
501 *auth_context = ac;
502 } else
503 krb5_auth_con_free (context, ac);
504 free_EtypeList(&etypes);
505 return 0;
506 out:
507 if (t)
508 krb5_free_ticket (context, t);
509 if (auth_context == NULL || *auth_context == NULL)
510 krb5_auth_con_free (context, ac);
511 return ret;
512}
513
514/*
515 *
516 */
517
518struct krb5_rd_req_in_ctx_data {
519 krb5_keytab keytab;
520 krb5_keyblock *keyblock;
521 krb5_boolean check_pac;
522};
523
524struct krb5_rd_req_out_ctx_data {
525 krb5_keyblock *keyblock;
526 krb5_flags ap_req_options;
527 krb5_ticket *ticket;
528 krb5_principal server;
529};
530
531/**
532 * Allocate a krb5_rd_req_in_ctx as an input parameter to
533 * krb5_rd_req_ctx(). The caller should free the context with
534 * krb5_rd_req_in_ctx_free() when done with the context.
535 *
536 * @param context Keberos 5 context.
537 * @param ctx in ctx to krb5_rd_req_ctx().
538 *
539 * @return Kerberos 5 error code, see krb5_get_error_message().
540 *
541 * @ingroup krb5_auth
542 */
543
544KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
545krb5_rd_req_in_ctx_alloc(krb5_context context, krb5_rd_req_in_ctx *ctx)
546{
547 *ctx = calloc(1, sizeof(**ctx));
548 if (*ctx == NULL) {
549 krb5_set_error_message(context, ENOMEM,
550 N_("malloc: out of memory", ""));
551 return ENOMEM;
552 }
553 (*ctx)->check_pac = (context->flags & KRB5_CTX_F_CHECK_PAC) ? 1 : 0;
554 return 0;
555}
556
557/**
558 * Set the keytab that krb5_rd_req_ctx() will use.
559 *
560 * @param context Keberos 5 context.
561 * @param in in ctx to krb5_rd_req_ctx().
562 * @param keytab keytab that krb5_rd_req_ctx() will use, only copy the
563 * pointer, so the caller must free they keytab after
564 * krb5_rd_req_in_ctx_free() is called.
565 *
566 * @return Kerberos 5 error code, see krb5_get_error_message().
567 *
568 * @ingroup krb5_auth
569 */
570
571KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
572krb5_rd_req_in_set_keytab(krb5_context context,
573 krb5_rd_req_in_ctx in,
574 krb5_keytab keytab)
575{
576 in->keytab = keytab;
577 return 0;
578}
579
580/**
581 * Set if krb5_rq_red() is going to check the Windows PAC or not
582 *
583 * @param context Keberos 5 context.
584 * @param in krb5_rd_req_in_ctx to check the option on.
585 * @param flag flag to select if to check the pac (TRUE) or not (FALSE).
586 *
587 * @return Kerberos 5 error code, see krb5_get_error_message().
588 *
589 * @ingroup krb5_auth
590 */
591
592KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
593krb5_rd_req_in_set_pac_check(krb5_context context,
594 krb5_rd_req_in_ctx in,
595 krb5_boolean flag)
596{
597 in->check_pac = flag;
598 return 0;
599}
600
601
602KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
603krb5_rd_req_in_set_keyblock(krb5_context context,
604 krb5_rd_req_in_ctx in,
605 krb5_keyblock *keyblock)
606{
607 in->keyblock = keyblock; /* XXX should make copy */
608 return 0;
609}
610
611KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
612krb5_rd_req_out_get_ap_req_options(krb5_context context,
613 krb5_rd_req_out_ctx out,
614 krb5_flags *ap_req_options)
615{
616 *ap_req_options = out->ap_req_options;
617 return 0;
618}
619
620KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
621krb5_rd_req_out_get_ticket(krb5_context context,
622 krb5_rd_req_out_ctx out,
623 krb5_ticket **ticket)
624{
625 return krb5_copy_ticket(context, out->ticket, ticket);
626}
627
628KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
629krb5_rd_req_out_get_keyblock(krb5_context context,
630 krb5_rd_req_out_ctx out,
631 krb5_keyblock **keyblock)
632{
633 return krb5_copy_keyblock(context, out->keyblock, keyblock);
634}
635
636/**
637 * Get the principal that was used in the request from the
638 * client. Might not match whats in the ticket if krb5_rd_req_ctx()
639 * searched in the keytab for a matching key.
640 *
641 * @param context a Kerberos 5 context.
642 * @param out a krb5_rd_req_out_ctx from krb5_rd_req_ctx().
643 * @param principal return principal, free with krb5_free_principal().
644 *
645 * @ingroup krb5_auth
646 */
647
648KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
649krb5_rd_req_out_get_server(krb5_context context,
650 krb5_rd_req_out_ctx out,
651 krb5_principal *principal)
652{
653 return krb5_copy_principal(context, out->server, principal);
654}
655
656KRB5_LIB_FUNCTION void KRB5_LIB_CALL
657krb5_rd_req_in_ctx_free(krb5_context context, krb5_rd_req_in_ctx ctx)
658{
659 free(ctx);
660}
661
662/**
663 * Free the krb5_rd_req_out_ctx.
664 *
665 * @param context Keberos 5 context.
666 * @param ctx krb5_rd_req_out_ctx context to free.
667 *
668 * @ingroup krb5_auth
669 */
670
671KRB5_LIB_FUNCTION void KRB5_LIB_CALL
672krb5_rd_req_out_ctx_free(krb5_context context, krb5_rd_req_out_ctx ctx)
673{
674 if (ctx->ticket)
675 krb5_free_ticket(context, ctx->ticket);
676 if (ctx->keyblock)
677 krb5_free_keyblock(context, ctx->keyblock);
678 if (ctx->server)
679 krb5_free_principal(context, ctx->server);
680 free(ctx);
681}
682
683/*
684 *
685 */
686
687KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
688krb5_rd_req(krb5_context context,
689 krb5_auth_context *auth_context,
690 const krb5_data *inbuf,
691 krb5_const_principal server,
692 krb5_keytab keytab,
693 krb5_flags *ap_req_options,
694 krb5_ticket **ticket)
695{
696 krb5_error_code ret;
697 krb5_rd_req_in_ctx in;
698 krb5_rd_req_out_ctx out;
699
700 ret = krb5_rd_req_in_ctx_alloc(context, &in);
701 if (ret)
702 return ret;
703
704 ret = krb5_rd_req_in_set_keytab(context, in, keytab);
705 if (ret) {
706 krb5_rd_req_in_ctx_free(context, in);
707 return ret;
708 }
709
710 ret = krb5_rd_req_ctx(context, auth_context, inbuf, server, in, &out);
711 krb5_rd_req_in_ctx_free(context, in);
712 if (ret)
713 return ret;
714
715 if (ap_req_options)
716 *ap_req_options = out->ap_req_options;
717 if (ticket) {
718 ret = krb5_copy_ticket(context, out->ticket, ticket);
719 if (ret)
720 goto out;
721 }
722
723out:
724 krb5_rd_req_out_ctx_free(context, out);
725 return ret;
726}
727
728/*
729 *
730 */
731
732KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
733krb5_rd_req_with_keyblock(krb5_context context,
734 krb5_auth_context *auth_context,
735 const krb5_data *inbuf,
736 krb5_const_principal server,
737 krb5_keyblock *keyblock,
738 krb5_flags *ap_req_options,
739 krb5_ticket **ticket)
740{
741 krb5_error_code ret;
742 krb5_rd_req_in_ctx in;
743 krb5_rd_req_out_ctx out;
744
745 ret = krb5_rd_req_in_ctx_alloc(context, &in);
746 if (ret)
747 return ret;
748
749 ret = krb5_rd_req_in_set_keyblock(context, in, keyblock);
750 if (ret) {
751 krb5_rd_req_in_ctx_free(context, in);
752 return ret;
753 }
754
755 ret = krb5_rd_req_ctx(context, auth_context, inbuf, server, in, &out);
756 krb5_rd_req_in_ctx_free(context, in);
757 if (ret)
758 return ret;
759
760 if (ap_req_options)
761 *ap_req_options = out->ap_req_options;
762 if (ticket) {
763 ret = krb5_copy_ticket(context, out->ticket, ticket);
764 if (ret)
765 goto out;
766 }
767
768out:
769 krb5_rd_req_out_ctx_free(context, out);
770 return ret;
771}
772
773/*
774 *
775 */
776
777static krb5_error_code
778get_key_from_keytab(krb5_context context,
779 krb5_ap_req *ap_req,
780 krb5_const_principal server,
781 krb5_keytab keytab,
782 krb5_keyblock **out_key)
783{
784 krb5_keytab_entry entry;
785 krb5_error_code ret;
786 int kvno;
787 krb5_keytab real_keytab;
788
789 if(keytab == NULL)
790 krb5_kt_default(context, &real_keytab);
791 else
792 real_keytab = keytab;
793
794 if (ap_req->ticket.enc_part.kvno)
795 kvno = *ap_req->ticket.enc_part.kvno;
796 else
797 kvno = 0;
798
799 ret = krb5_kt_get_entry (context,
800 real_keytab,
801 server,
802 kvno,
803 ap_req->ticket.enc_part.etype,
804 &entry);
805 if(ret)
806 goto out;
807 ret = krb5_copy_keyblock(context, &entry.keyblock, out_key);
808 krb5_kt_free_entry (context, &entry);
809out:
810 if(keytab == NULL)
811 krb5_kt_close(context, real_keytab);
812
813 return ret;
814}
815
816/**
817 * The core server function that verify application authentication
818 * requests from clients.
819 *
820 * @param context Keberos 5 context.
821 * @param auth_context the authentication context, can be NULL, then
822 * default values for the authentication context will used.
823 * @param inbuf the (AP-REQ) authentication buffer
824 *
825 * @param server the server with authenticate as, if NULL the function
826 * will try to find any available credential in the keytab
827 * that will verify the reply. The function will prefer the
828 * server the server client specified in the AP-REQ, but if
829 * there is no mach, it will try all keytab entries for a
830 * match. This have serious performance issues for larger keytabs.
831 *
832 * @param inctx control the behavior of the function, if NULL, the
833 * default behavior is used.
834 * @param outctx the return outctx, free with krb5_rd_req_out_ctx_free().
835 * @return Kerberos 5 error code, see krb5_get_error_message().
836 *
837 * @ingroup krb5_auth
838 */
839
840KRB5_LIB_FUNCTION krb5_error_code KRB5_LIB_CALL
841krb5_rd_req_ctx(krb5_context context,
842 krb5_auth_context *auth_context,
843 const krb5_data *inbuf,
844 krb5_const_principal server,
845 krb5_rd_req_in_ctx inctx,
846 krb5_rd_req_out_ctx *outctx)
847{
848 krb5_error_code ret;
849 krb5_ap_req ap_req;
850 krb5_rd_req_out_ctx o = NULL;
851 krb5_keytab id = NULL, keytab = NULL;
852 krb5_principal service = NULL;
853
854 *outctx = NULL;
855
856 o = calloc(1, sizeof(*o));
857 if (o == NULL) {
858 krb5_set_error_message(context, ENOMEM,
859 N_("malloc: out of memory", ""));
860 return ENOMEM;
861 }
862
863 if (*auth_context == NULL) {
864 ret = krb5_auth_con_init(context, auth_context);
865 if (ret)
866 goto out;
867 }
868
869 ret = krb5_decode_ap_req(context, inbuf, &ap_req);
870 if(ret)
871 goto out;
872
873 /* Save that principal that was in the request */
874 ret = _krb5_principalname2krb5_principal(context,
875 &o->server,
876 ap_req.ticket.sname,
877 ap_req.ticket.realm);
878 if (ret)
879 goto out;
880
881 if (ap_req.ap_options.use_session_key &&
882 (*auth_context)->keyblock == NULL) {
883 ret = KRB5KRB_AP_ERR_NOKEY;
884 krb5_set_error_message(context, ret,
885 N_("krb5_rd_req: user to user auth "
886 "without session key given", ""));
887 goto out;
888 }
889
890 if (inctx && inctx->keytab)
891 id = inctx->keytab;
892
893 if((*auth_context)->keyblock){
894 ret = krb5_copy_keyblock(context,
895 (*auth_context)->keyblock,
896 &o->keyblock);
897 if (ret)
898 goto out;
899 } else if(inctx && inctx->keyblock){
900 ret = krb5_copy_keyblock(context,
901 inctx->keyblock,
902 &o->keyblock);
903 if (ret)
904 goto out;
905 } else {
906
907 if(id == NULL) {
908 krb5_kt_default(context, &keytab);
909 id = keytab;
910 }
911 if (id == NULL)
912 goto out;
913
914 if (server == NULL) {
915 ret = _krb5_principalname2krb5_principal(context,
916 &service,
917 ap_req.ticket.sname,
918 ap_req.ticket.realm);
919 if (ret)
920 goto out;
921 server = service;
922 }
923
924 ret = get_key_from_keytab(context,
925 &ap_req,
926 server,
927 id,
928 &o->keyblock);
929 if (ret) {
930 /* If caller specified a server, fail. */
931 if (service == NULL && (context->flags & KRB5_CTX_F_RD_REQ_IGNORE) == 0)
932 goto out;
933 /* Otherwise, fall back to iterating over the keytab. This
934 * have serious performace issues for larger keytab.
935 */
936 o->keyblock = NULL;
937 }
938 }
939
940 if (o->keyblock) {
941 /*
942 * We got an exact keymatch, use that.
943 */
944
945 ret = krb5_verify_ap_req2(context,
946 auth_context,
947 &ap_req,
948 server,
949 o->keyblock,
950 0,
951 &o->ap_req_options,
952 &o->ticket,
953 KRB5_KU_AP_REQ_AUTH);
954
955 if (ret)
956 goto out;
957
958 } else {
959 /*
960 * Interate over keytab to find a key that can decrypt the request.
961 */
962
963 krb5_keytab_entry entry;
964 krb5_kt_cursor cursor;
965 int done = 0, kvno = 0;
966
967 memset(&cursor, 0, sizeof(cursor));
968
969 if (ap_req.ticket.enc_part.kvno)
970 kvno = *ap_req.ticket.enc_part.kvno;
971
972 ret = krb5_kt_start_seq_get(context, id, &cursor);
973 if (ret)
974 goto out;
975
976 done = 0;
977 while (!done) {
978 krb5_principal p;
979
980 ret = krb5_kt_next_entry(context, id, &entry, &cursor);
981 if (ret) {
982 _krb5_kt_principal_not_found(context, ret, id, o->server,
983 ap_req.ticket.enc_part.etype,
984 kvno);
985 goto out;
986 }
987
988 if (entry.keyblock.keytype != ap_req.ticket.enc_part.etype) {
989 krb5_kt_free_entry (context, &entry);
990 continue;
991 }
992
993 ret = krb5_verify_ap_req2(context,
994 auth_context,
995 &ap_req,
996 server,
997 &entry.keyblock,
998 0,
999 &o->ap_req_options,
1000 &o->ticket,
1001 KRB5_KU_AP_REQ_AUTH);
1002 if (ret) {
1003 krb5_kt_free_entry (context, &entry);
1004 continue;
1005 }
1006
1007 /*
1008 * Found a match, save the keyblock for PAC processing,
1009 * and update the service principal in the ticket to match
1010 * whatever is in the keytab.
1011 */
1012
1013 ret = krb5_copy_keyblock(context,
1014 &entry.keyblock,
1015 &o->keyblock);
1016 if (ret) {
1017 krb5_kt_free_entry (context, &entry);
1018 goto out;
1019 }
1020
1021 ret = krb5_copy_principal(context, entry.principal, &p);
1022 if (ret) {
1023 krb5_kt_free_entry (context, &entry);
1024 goto out;
1025 }
1026 krb5_free_principal(context, o->ticket->server);
1027 o->ticket->server = p;
1028
1029 krb5_kt_free_entry (context, &entry);
1030
1031 done = 1;
1032 }
1033 krb5_kt_end_seq_get (context, id, &cursor);
1034 }
1035
1036 /* If there is a PAC, verify its server signature */
1037 if (inctx == NULL || inctx->check_pac) {
1038 krb5_pac pac;
1039 krb5_data data;
1040
1041 ret = krb5_ticket_get_authorization_data_type(context,
1042 o->ticket,
1043 KRB5_AUTHDATA_WIN2K_PAC,
1044 &data);
1045 if (ret == 0) {
1046 ret = krb5_pac_parse(context, data.data, data.length, &pac);
1047 krb5_data_free(&data);
1048 if (ret)
1049 goto out;
1050
1051 ret = krb5_pac_verify(context,
1052 pac,
1053 o->ticket->ticket.authtime,
1054 o->ticket->client,
1055 o->keyblock,
1056 NULL);
1057 krb5_pac_free(context, pac);
1058 if (ret)
1059 goto out;
1060 } else
1061 ret = 0;
1062 }
1063out:
1064
1065 if (ret || outctx == NULL) {
1066 krb5_rd_req_out_ctx_free(context, o);
1067 } else
1068 *outctx = o;
1069
1070 free_AP_REQ(&ap_req);
1071
1072 if (service)
1073 krb5_free_principal(context, service);
1074
1075 if (keytab)
1076 krb5_kt_close(context, keytab);
1077
1078 return ret;
1079}
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