xref: /freebsd/crypto/heimdal/lib/gssapi/krb5/init_sec_context.c (revision 62cfcf62f627e5093fb37026a6d8c98e4d2ef04c)
1 /*
2  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
3  * (Royal Institute of Technology, Stockholm, Sweden).
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  *
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  *
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * 3. Neither the name of the Institute nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #include "gsskrb5_locl.h"
35 
36 /*
37  * copy the addresses from `input_chan_bindings' (if any) to
38  * the auth context `ac'
39  */
40 
41 static OM_uint32
42 set_addresses (krb5_context context,
43 	       krb5_auth_context ac,
44 	       const gss_channel_bindings_t input_chan_bindings)
45 {
46     /* Port numbers are expected to be in application_data.value,
47      * initator's port first */
48 
49     krb5_address initiator_addr, acceptor_addr;
50     krb5_error_code kret;
51 
52     if (input_chan_bindings == GSS_C_NO_CHANNEL_BINDINGS
53 	|| input_chan_bindings->application_data.length !=
54 	2 * sizeof(ac->local_port))
55 	return 0;
56 
57     memset(&initiator_addr, 0, sizeof(initiator_addr));
58     memset(&acceptor_addr, 0, sizeof(acceptor_addr));
59 
60     ac->local_port =
61 	*(int16_t *) input_chan_bindings->application_data.value;
62 
63     ac->remote_port =
64 	*((int16_t *) input_chan_bindings->application_data.value + 1);
65 
66     kret = _gsskrb5i_address_to_krb5addr(context,
67 					 input_chan_bindings->acceptor_addrtype,
68 					 &input_chan_bindings->acceptor_address,
69 					 ac->remote_port,
70 					 &acceptor_addr);
71     if (kret)
72 	return kret;
73 
74     kret = _gsskrb5i_address_to_krb5addr(context,
75 					 input_chan_bindings->initiator_addrtype,
76 					 &input_chan_bindings->initiator_address,
77 					 ac->local_port,
78 					 &initiator_addr);
79     if (kret) {
80 	krb5_free_address (context, &acceptor_addr);
81 	return kret;
82     }
83 
84     kret = krb5_auth_con_setaddrs(context,
85 				  ac,
86 				  &initiator_addr,  /* local address */
87 				  &acceptor_addr);  /* remote address */
88 
89     krb5_free_address (context, &initiator_addr);
90     krb5_free_address (context, &acceptor_addr);
91 
92 #if 0
93     free(input_chan_bindings->application_data.value);
94     input_chan_bindings->application_data.value = NULL;
95     input_chan_bindings->application_data.length = 0;
96 #endif
97 
98     return kret;
99 }
100 
101 OM_uint32
102 _gsskrb5_create_ctx(
103         OM_uint32 * minor_status,
104 	gss_ctx_id_t * context_handle,
105 	krb5_context context,
106  	const gss_channel_bindings_t input_chan_bindings,
107  	enum gss_ctx_id_t_state state)
108 {
109     krb5_error_code kret;
110     gsskrb5_ctx ctx;
111 
112     *context_handle = NULL;
113 
114     ctx = malloc(sizeof(*ctx));
115     if (ctx == NULL) {
116 	*minor_status = ENOMEM;
117 	return GSS_S_FAILURE;
118     }
119     ctx->auth_context		= NULL;
120     ctx->deleg_auth_context	= NULL;
121     ctx->source			= NULL;
122     ctx->target			= NULL;
123     ctx->kcred			= NULL;
124     ctx->ccache			= NULL;
125     ctx->state			= state;
126     ctx->flags			= 0;
127     ctx->more_flags		= 0;
128     ctx->service_keyblock	= NULL;
129     ctx->ticket			= NULL;
130     krb5_data_zero(&ctx->fwd_data);
131     ctx->lifetime		= GSS_C_INDEFINITE;
132     ctx->order			= NULL;
133     ctx->crypto			= NULL;
134     HEIMDAL_MUTEX_init(&ctx->ctx_id_mutex);
135 
136     kret = krb5_auth_con_init (context, &ctx->auth_context);
137     if (kret) {
138 	*minor_status = kret;
139 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
140 	return GSS_S_FAILURE;
141     }
142 
143     kret = krb5_auth_con_init (context, &ctx->deleg_auth_context);
144     if (kret) {
145 	*minor_status = kret;
146 	krb5_auth_con_free(context, ctx->auth_context);
147 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
148 	return GSS_S_FAILURE;
149     }
150 
151     kret = set_addresses(context, ctx->auth_context, input_chan_bindings);
152     if (kret) {
153 	*minor_status = kret;
154 
155 	krb5_auth_con_free(context, ctx->auth_context);
156 	krb5_auth_con_free(context, ctx->deleg_auth_context);
157 
158 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
159 
160 	return GSS_S_BAD_BINDINGS;
161     }
162 
163     kret = set_addresses(context, ctx->deleg_auth_context, input_chan_bindings);
164     if (kret) {
165 	*minor_status = kret;
166 
167 	krb5_auth_con_free(context, ctx->auth_context);
168 	krb5_auth_con_free(context, ctx->deleg_auth_context);
169 
170 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
171 
172 	return GSS_S_BAD_BINDINGS;
173     }
174 
175     /*
176      * We need a sequence number
177      */
178 
179     krb5_auth_con_addflags(context,
180 			   ctx->auth_context,
181 			   KRB5_AUTH_CONTEXT_DO_SEQUENCE |
182 			   KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED,
183 			   NULL);
184 
185     /*
186      * We need a sequence number
187      */
188 
189     krb5_auth_con_addflags(context,
190 			   ctx->deleg_auth_context,
191 			   KRB5_AUTH_CONTEXT_DO_SEQUENCE |
192 			   KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED,
193 			   NULL);
194 
195     *context_handle = (gss_ctx_id_t)ctx;
196 
197     return GSS_S_COMPLETE;
198 }
199 
200 
201 static OM_uint32
202 gsskrb5_get_creds(
203         OM_uint32 * minor_status,
204 	krb5_context context,
205 	krb5_ccache ccache,
206 	gsskrb5_ctx ctx,
207 	const gss_name_t target_name,
208 	int use_dns,
209 	OM_uint32 time_req,
210 	OM_uint32 * time_rec)
211 {
212     OM_uint32 ret;
213     krb5_error_code kret;
214     krb5_creds this_cred;
215     OM_uint32 lifetime_rec;
216 
217     if (ctx->target) {
218 	krb5_free_principal(context, ctx->target);
219 	ctx->target = NULL;
220     }
221     if (ctx->kcred) {
222 	krb5_free_creds(context, ctx->kcred);
223 	ctx->kcred = NULL;
224     }
225 
226     ret = _gsskrb5_canon_name(minor_status, context, use_dns,
227 			      ctx->source, target_name, &ctx->target);
228     if (ret)
229 	return ret;
230 
231     memset(&this_cred, 0, sizeof(this_cred));
232     this_cred.client = ctx->source;
233     this_cred.server = ctx->target;
234 
235     if (time_req && time_req != GSS_C_INDEFINITE) {
236 	krb5_timestamp ts;
237 
238 	krb5_timeofday (context, &ts);
239 	this_cred.times.endtime = ts + time_req;
240     } else {
241 	this_cred.times.endtime   = 0;
242     }
243 
244     this_cred.session.keytype = KEYTYPE_NULL;
245 
246     kret = krb5_get_credentials(context,
247 				0,
248 				ccache,
249 				&this_cred,
250 				&ctx->kcred);
251     if (kret) {
252 	*minor_status = kret;
253 	return GSS_S_FAILURE;
254     }
255 
256     ctx->lifetime = ctx->kcred->times.endtime;
257 
258     ret = _gsskrb5_lifetime_left(minor_status, context,
259 				 ctx->lifetime, &lifetime_rec);
260     if (ret) return ret;
261 
262     if (lifetime_rec == 0) {
263 	*minor_status = 0;
264 	return GSS_S_CONTEXT_EXPIRED;
265     }
266 
267     if (time_rec) *time_rec = lifetime_rec;
268 
269     return GSS_S_COMPLETE;
270 }
271 
272 static OM_uint32
273 gsskrb5_initiator_ready(
274 	OM_uint32 * minor_status,
275 	gsskrb5_ctx ctx,
276 	krb5_context context)
277 {
278     OM_uint32 ret;
279     int32_t seq_number;
280     int is_cfx = 0;
281     OM_uint32 flags = ctx->flags;
282 
283     krb5_free_creds(context, ctx->kcred);
284     ctx->kcred = NULL;
285 
286     if (ctx->more_flags & CLOSE_CCACHE)
287 	krb5_cc_close(context, ctx->ccache);
288     ctx->ccache = NULL;
289 
290     krb5_auth_con_getremoteseqnumber (context, ctx->auth_context, &seq_number);
291 
292     _gsskrb5i_is_cfx(context, ctx, 0);
293     is_cfx = (ctx->more_flags & IS_CFX);
294 
295     ret = _gssapi_msg_order_create(minor_status,
296 				   &ctx->order,
297 				   _gssapi_msg_order_f(flags),
298 				   seq_number, 0, is_cfx);
299     if (ret) return ret;
300 
301     ctx->state	= INITIATOR_READY;
302     ctx->more_flags	|= OPEN;
303 
304     return GSS_S_COMPLETE;
305 }
306 
307 /*
308  * handle delegated creds in init-sec-context
309  */
310 
311 static void
312 do_delegation (krb5_context context,
313 	       krb5_auth_context ac,
314 	       krb5_ccache ccache,
315 	       krb5_creds *cred,
316 	       krb5_const_principal name,
317 	       krb5_data *fwd_data,
318 	       uint32_t flagmask,
319 	       uint32_t *flags)
320 {
321     krb5_creds creds;
322     KDCOptions fwd_flags;
323     krb5_error_code kret;
324 
325     memset (&creds, 0, sizeof(creds));
326     krb5_data_zero (fwd_data);
327 
328     kret = krb5_cc_get_principal(context, ccache, &creds.client);
329     if (kret)
330 	goto out;
331 
332     kret = krb5_make_principal(context,
333 			       &creds.server,
334 			       creds.client->realm,
335 			       KRB5_TGS_NAME,
336 			       creds.client->realm,
337 			       NULL);
338     if (kret)
339 	goto out;
340 
341     creds.times.endtime = 0;
342 
343     memset(&fwd_flags, 0, sizeof(fwd_flags));
344     fwd_flags.forwarded = 1;
345     fwd_flags.forwardable = 1;
346 
347     if ( /*target_name->name.name_type != KRB5_NT_SRV_HST ||*/
348 	name->name.name_string.len < 2)
349 	goto out;
350 
351     kret = krb5_get_forwarded_creds(context,
352 				    ac,
353 				    ccache,
354 				    KDCOptions2int(fwd_flags),
355 				    name->name.name_string.val[1],
356 				    &creds,
357 				    fwd_data);
358 
359  out:
360     if (kret)
361 	*flags &= ~flagmask;
362     else
363 	*flags |= flagmask;
364 
365     if (creds.client)
366 	krb5_free_principal(context, creds.client);
367     if (creds.server)
368 	krb5_free_principal(context, creds.server);
369 }
370 
371 /*
372  * first stage of init-sec-context
373  */
374 
375 static OM_uint32
376 init_auth
377 (OM_uint32 * minor_status,
378  gsskrb5_cred cred,
379  gsskrb5_ctx ctx,
380  krb5_context context,
381  gss_name_t name,
382  const gss_OID mech_type,
383  OM_uint32 req_flags,
384  OM_uint32 time_req,
385  const gss_buffer_t input_token,
386  gss_OID * actual_mech_type,
387  gss_buffer_t output_token,
388  OM_uint32 * ret_flags,
389  OM_uint32 * time_rec
390     )
391 {
392     OM_uint32 ret = GSS_S_FAILURE;
393     krb5_error_code kret;
394     krb5_data outbuf;
395     krb5_data fwd_data;
396     OM_uint32 lifetime_rec;
397     int allow_dns = 1;
398 
399     krb5_data_zero(&outbuf);
400     krb5_data_zero(&fwd_data);
401 
402     *minor_status = 0;
403 
404     if (actual_mech_type)
405 	*actual_mech_type = GSS_KRB5_MECHANISM;
406 
407     if (cred == NULL) {
408 	kret = krb5_cc_default (context, &ctx->ccache);
409 	if (kret) {
410 	    *minor_status = kret;
411 	    ret = GSS_S_FAILURE;
412 	    goto failure;
413 	}
414 	ctx->more_flags |= CLOSE_CCACHE;
415     } else
416 	ctx->ccache = cred->ccache;
417 
418     kret = krb5_cc_get_principal (context, ctx->ccache, &ctx->source);
419     if (kret) {
420 	*minor_status = kret;
421 	ret = GSS_S_FAILURE;
422 	goto failure;
423     }
424 
425     /*
426      * This is hideous glue for (NFS) clients that wants to limit the
427      * available enctypes to what it can support (encryption in
428      * kernel). If there is no enctypes selected for this credential,
429      * reset it to the default set of enctypes.
430      */
431     {
432 	krb5_enctype *enctypes = NULL;
433 
434 	if (cred && cred->enctypes)
435 	    enctypes = cred->enctypes;
436 	krb5_set_default_in_tkt_etypes(context, enctypes);
437     }
438 
439     /* canon name if needed for client + target realm */
440     kret = krb5_cc_get_config(context, ctx->ccache, NULL,
441 			      "realm-config", &outbuf);
442     if (kret == 0) {
443 	/* XXX 2 is no server canon */
444 	if (outbuf.length < 1 || ((((unsigned char *)outbuf.data)[0]) & 2))
445 	    allow_dns = 0;
446 	krb5_data_free(&outbuf);
447     }
448 
449     /*
450      * First we try w/o dns, hope that the KDC have register alias
451      * (and referrals if cross realm) for this principal. If that
452      * fails and if we are allowed to using this realm try again with
453      * DNS canonicalizion.
454      */
455     ret = gsskrb5_get_creds(minor_status, context, ctx->ccache,
456 			    ctx, name, 0, time_req,
457 			    time_rec);
458     if (ret && allow_dns)
459 	ret = gsskrb5_get_creds(minor_status, context, ctx->ccache,
460 				ctx, name, 1, time_req,
461 				time_rec);
462     if (ret)
463 	goto failure;
464 
465     ctx->lifetime = ctx->kcred->times.endtime;
466 
467     ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
468     if (ret)
469 	goto failure;
470 
471     ret = _gsskrb5_lifetime_left(minor_status,
472 				 context,
473 				 ctx->lifetime,
474 				 &lifetime_rec);
475     if (ret)
476 	goto failure;
477 
478     if (lifetime_rec == 0) {
479 	*minor_status = 0;
480 	ret = GSS_S_CONTEXT_EXPIRED;
481 	goto failure;
482     }
483 
484     krb5_auth_con_setkey(context,
485 			 ctx->auth_context,
486 			 &ctx->kcred->session);
487 
488     kret = krb5_auth_con_generatelocalsubkey(context,
489 					     ctx->auth_context,
490 					     &ctx->kcred->session);
491     if(kret) {
492 	*minor_status = kret;
493 	ret = GSS_S_FAILURE;
494 	goto failure;
495     }
496 
497     return GSS_S_COMPLETE;
498 
499 failure:
500     if (ctx->ccache && (ctx->more_flags & CLOSE_CCACHE))
501 	krb5_cc_close(context, ctx->ccache);
502     ctx->ccache = NULL;
503 
504     return ret;
505 
506 }
507 
508 static OM_uint32
509 init_auth_restart
510 (OM_uint32 * minor_status,
511  gsskrb5_cred cred,
512  gsskrb5_ctx ctx,
513  krb5_context context,
514  OM_uint32 req_flags,
515  const gss_channel_bindings_t input_chan_bindings,
516  const gss_buffer_t input_token,
517  gss_OID * actual_mech_type,
518  gss_buffer_t output_token,
519  OM_uint32 * ret_flags,
520  OM_uint32 * time_rec
521     )
522 {
523     OM_uint32 ret = GSS_S_FAILURE;
524     krb5_error_code kret;
525     krb5_flags ap_options;
526     krb5_data outbuf;
527     uint32_t flags;
528     krb5_data authenticator;
529     Checksum cksum;
530     krb5_enctype enctype;
531     krb5_data fwd_data, timedata;
532     int32_t offset = 0, oldoffset = 0;
533     uint32_t flagmask;
534 
535     krb5_data_zero(&outbuf);
536     krb5_data_zero(&fwd_data);
537 
538     *minor_status = 0;
539 
540     /*
541      * If the credential doesn't have ok-as-delegate, check if there
542      * is a realm setting and use that.
543      */
544     if (!ctx->kcred->flags.b.ok_as_delegate) {
545 	krb5_data data;
546 
547 	ret = krb5_cc_get_config(context, ctx->ccache, NULL,
548 				 "realm-config", &data);
549 	if (ret == 0) {
550 	    /* XXX 1 is use ok-as-delegate */
551 	    if (data.length < 1 || ((((unsigned char *)data.data)[0]) & 1) == 0)
552 		req_flags &= ~(GSS_C_DELEG_FLAG|GSS_C_DELEG_POLICY_FLAG);
553 	    krb5_data_free(&data);
554 	}
555     }
556 
557     flagmask = 0;
558 
559     /* if we used GSS_C_DELEG_POLICY_FLAG, trust KDC */
560     if ((req_flags & GSS_C_DELEG_POLICY_FLAG)
561 	&& ctx->kcred->flags.b.ok_as_delegate)
562 	flagmask |= GSS_C_DELEG_FLAG | GSS_C_DELEG_POLICY_FLAG;
563     /* if there still is a GSS_C_DELEG_FLAG, use that */
564     if (req_flags & GSS_C_DELEG_FLAG)
565 	flagmask |= GSS_C_DELEG_FLAG;
566 
567 
568     flags = 0;
569     ap_options = 0;
570     if (flagmask & GSS_C_DELEG_FLAG) {
571 	do_delegation (context,
572 		       ctx->deleg_auth_context,
573 		       ctx->ccache, ctx->kcred, ctx->target,
574 		       &fwd_data, flagmask, &flags);
575     }
576 
577     if (req_flags & GSS_C_MUTUAL_FLAG) {
578 	flags |= GSS_C_MUTUAL_FLAG;
579 	ap_options |= AP_OPTS_MUTUAL_REQUIRED;
580     }
581 
582     if (req_flags & GSS_C_REPLAY_FLAG)
583 	flags |= GSS_C_REPLAY_FLAG;
584     if (req_flags & GSS_C_SEQUENCE_FLAG)
585 	flags |= GSS_C_SEQUENCE_FLAG;
586 #if 0
587     if (req_flags & GSS_C_ANON_FLAG)
588 	;                               /* XXX */
589 #endif
590     if (req_flags & GSS_C_DCE_STYLE) {
591 	/* GSS_C_DCE_STYLE implies GSS_C_MUTUAL_FLAG */
592 	flags |= GSS_C_DCE_STYLE | GSS_C_MUTUAL_FLAG;
593 	ap_options |= AP_OPTS_MUTUAL_REQUIRED;
594     }
595     if (req_flags & GSS_C_IDENTIFY_FLAG)
596 	flags |= GSS_C_IDENTIFY_FLAG;
597     if (req_flags & GSS_C_EXTENDED_ERROR_FLAG)
598 	flags |= GSS_C_EXTENDED_ERROR_FLAG;
599 
600     if (req_flags & GSS_C_CONF_FLAG) {
601 	flags |= GSS_C_CONF_FLAG;
602     }
603     if (req_flags & GSS_C_INTEG_FLAG) {
604 	flags |= GSS_C_INTEG_FLAG;
605     }
606     if (cred == NULL || !(cred->cred_flags & GSS_CF_NO_CI_FLAGS)) {
607 	flags |= GSS_C_CONF_FLAG;
608 	flags |= GSS_C_INTEG_FLAG;
609     }
610     flags |= GSS_C_TRANS_FLAG;
611 
612     if (ret_flags)
613 	*ret_flags = flags;
614     ctx->flags = flags;
615     ctx->more_flags |= LOCAL;
616 
617     ret = _gsskrb5_create_8003_checksum (minor_status,
618 					 input_chan_bindings,
619 					 flags,
620 					 &fwd_data,
621 					 &cksum);
622     krb5_data_free (&fwd_data);
623     if (ret)
624 	goto failure;
625 
626     enctype = ctx->auth_context->keyblock->keytype;
627 
628     ret = krb5_cc_get_config(context, ctx->ccache, ctx->target,
629 			     "time-offset", &timedata);
630     if (ret == 0) {
631 	if (timedata.length == 4) {
632 	    const u_char *p = timedata.data;
633 	    offset = (p[0] <<24) | (p[1] << 16) | (p[2] << 8) | (p[3] << 0);
634 	}
635 	krb5_data_free(&timedata);
636     }
637 
638     if (offset) {
639 	krb5_get_kdc_sec_offset (context, &oldoffset, NULL);
640 	krb5_set_kdc_sec_offset (context, offset, -1);
641     }
642 
643     kret = _krb5_build_authenticator(context,
644 				     ctx->auth_context,
645 				     enctype,
646 				     ctx->kcred,
647 				     &cksum,
648 				     &authenticator,
649 				     KRB5_KU_AP_REQ_AUTH);
650 
651     if (kret) {
652 	if (offset)
653 	    krb5_set_kdc_sec_offset (context, oldoffset, -1);
654 	*minor_status = kret;
655 	ret = GSS_S_FAILURE;
656 	goto failure;
657     }
658 
659     kret = krb5_build_ap_req (context,
660 			      enctype,
661 			      ctx->kcred,
662 			      ap_options,
663 			      authenticator,
664 			      &outbuf);
665     if (offset)
666 	krb5_set_kdc_sec_offset (context, oldoffset, -1);
667     if (kret) {
668 	*minor_status = kret;
669 	ret = GSS_S_FAILURE;
670 	goto failure;
671     }
672 
673     if (flags & GSS_C_DCE_STYLE) {
674 	output_token->value = outbuf.data;
675 	output_token->length = outbuf.length;
676     } else {
677         ret = _gsskrb5_encapsulate (minor_status, &outbuf, output_token,
678 				    (u_char *)(intptr_t)"\x01\x00",
679 				    GSS_KRB5_MECHANISM);
680 	krb5_data_free (&outbuf);
681 	if (ret)
682 	    goto failure;
683     }
684 
685     free_Checksum(&cksum);
686 
687     if (flags & GSS_C_MUTUAL_FLAG) {
688 	ctx->state = INITIATOR_WAIT_FOR_MUTAL;
689 	return GSS_S_CONTINUE_NEEDED;
690     }
691 
692     return gsskrb5_initiator_ready(minor_status, ctx, context);
693 failure:
694     if (ctx->ccache && (ctx->more_flags & CLOSE_CCACHE))
695 	krb5_cc_close(context, ctx->ccache);
696     ctx->ccache = NULL;
697 
698     return ret;
699 }
700 
701 static krb5_error_code
702 handle_error_packet(krb5_context context,
703 		    gsskrb5_ctx ctx,
704 		    krb5_data indata)
705 {
706     krb5_error_code kret;
707     KRB_ERROR error;
708 
709     kret = krb5_rd_error(context, &indata, &error);
710     if (kret == 0) {
711 	kret = krb5_error_from_rd_error(context, &error, NULL);
712 
713 	/* save the time skrew for this host */
714 	if (kret == KRB5KRB_AP_ERR_SKEW) {
715 	    krb5_data timedata;
716 	    unsigned char p[4];
717 	    int32_t t = error.stime - time(NULL);
718 
719 	    p[0] = (t >> 24) & 0xFF;
720 	    p[1] = (t >> 16) & 0xFF;
721 	    p[2] = (t >> 8)  & 0xFF;
722 	    p[3] = (t >> 0)  & 0xFF;
723 
724 	    timedata.data = p;
725 	    timedata.length = sizeof(p);
726 
727 	    krb5_cc_set_config(context, ctx->ccache, ctx->target,
728 			       "time-offset", &timedata);
729 
730 	    if ((ctx->more_flags & RETRIED) == 0)
731 		 ctx->state = INITIATOR_RESTART;
732 	    ctx->more_flags |= RETRIED;
733 	}
734 	free_KRB_ERROR (&error);
735     }
736     return kret;
737 }
738 
739 
740 static OM_uint32
741 repl_mutual
742 (OM_uint32 * minor_status,
743  gsskrb5_ctx ctx,
744  krb5_context context,
745  const gss_OID mech_type,
746  OM_uint32 req_flags,
747  OM_uint32 time_req,
748  const gss_channel_bindings_t input_chan_bindings,
749  const gss_buffer_t input_token,
750  gss_OID * actual_mech_type,
751  gss_buffer_t output_token,
752  OM_uint32 * ret_flags,
753  OM_uint32 * time_rec
754     )
755 {
756     OM_uint32 ret;
757     krb5_error_code kret;
758     krb5_data indata;
759     krb5_ap_rep_enc_part *repl;
760 
761     output_token->length = 0;
762     output_token->value = NULL;
763 
764     if (actual_mech_type)
765 	*actual_mech_type = GSS_KRB5_MECHANISM;
766 
767     if (IS_DCE_STYLE(ctx)) {
768 	/* There is no OID wrapping. */
769 	indata.length	= input_token->length;
770 	indata.data	= input_token->value;
771 	kret = krb5_rd_rep(context,
772 			   ctx->auth_context,
773 			   &indata,
774 			   &repl);
775 	if (kret) {
776 	    ret = _gsskrb5_decapsulate(minor_status,
777 				       input_token,
778 				       &indata,
779 				       "\x03\x00",
780 				       GSS_KRB5_MECHANISM);
781 	    if (ret == GSS_S_COMPLETE) {
782 		*minor_status = handle_error_packet(context, ctx, indata);
783 	    } else {
784 		*minor_status = kret;
785 	    }
786 	    return GSS_S_FAILURE;
787 	}
788     } else {
789 	ret = _gsskrb5_decapsulate (minor_status,
790 				    input_token,
791 				    &indata,
792 				    "\x02\x00",
793 				    GSS_KRB5_MECHANISM);
794 	if (ret == GSS_S_DEFECTIVE_TOKEN) {
795 	    /* check if there is an error token sent instead */
796 	    ret = _gsskrb5_decapsulate (minor_status,
797 					input_token,
798 					&indata,
799 					"\x03\x00",
800 					GSS_KRB5_MECHANISM);
801 	    if (ret == GSS_S_COMPLETE) {
802 		*minor_status = handle_error_packet(context, ctx, indata);
803 		return GSS_S_FAILURE;
804 	    }
805 	}
806 	kret = krb5_rd_rep (context,
807 			    ctx->auth_context,
808 			    &indata,
809 			    &repl);
810 	if (kret) {
811 	    *minor_status = kret;
812 	    return GSS_S_FAILURE;
813 	}
814     }
815 
816     krb5_free_ap_rep_enc_part (context,
817 			       repl);
818 
819     *minor_status = 0;
820     if (time_rec) {
821 	ret = _gsskrb5_lifetime_left(minor_status,
822 				     context,
823 				     ctx->lifetime,
824 				     time_rec);
825     } else {
826 	ret = GSS_S_COMPLETE;
827     }
828     if (ret_flags)
829 	*ret_flags = ctx->flags;
830 
831     if (req_flags & GSS_C_DCE_STYLE) {
832 	int32_t local_seq, remote_seq;
833 	krb5_data outbuf;
834 
835 	/*
836 	 * So DCE_STYLE is strange. The client echos the seq number
837 	 * that the server used in the server's mk_rep in its own
838 	 * mk_rep(). After when done, it resets to it's own seq number
839 	 * for the gss_wrap calls.
840 	 */
841 
842 	krb5_auth_con_getremoteseqnumber(context, ctx->auth_context, &remote_seq);
843 	krb5_auth_con_getlocalseqnumber(context, ctx->auth_context, &local_seq);
844 	krb5_auth_con_setlocalseqnumber(context, ctx->auth_context, remote_seq);
845 
846 	kret = krb5_mk_rep(context, ctx->auth_context, &outbuf);
847 	if (kret) {
848 	    *minor_status = kret;
849 	    return GSS_S_FAILURE;
850 	}
851 
852 	/* reset local seq number */
853 	krb5_auth_con_setlocalseqnumber(context, ctx->auth_context, local_seq);
854 
855 	output_token->length = outbuf.length;
856 	output_token->value  = outbuf.data;
857     }
858 
859     return gsskrb5_initiator_ready(minor_status, ctx, context);
860 }
861 
862 /*
863  * gss_init_sec_context
864  */
865 
866 OM_uint32 GSSAPI_CALLCONV _gsskrb5_init_sec_context
867 (OM_uint32 * minor_status,
868  const gss_cred_id_t cred_handle,
869  gss_ctx_id_t * context_handle,
870  const gss_name_t target_name,
871  const gss_OID mech_type,
872  OM_uint32 req_flags,
873  OM_uint32 time_req,
874  const gss_channel_bindings_t input_chan_bindings,
875  const gss_buffer_t input_token,
876  gss_OID * actual_mech_type,
877  gss_buffer_t output_token,
878  OM_uint32 * ret_flags,
879  OM_uint32 * time_rec
880     )
881 {
882     krb5_context context;
883     gsskrb5_cred cred = (gsskrb5_cred)cred_handle;
884     gsskrb5_ctx ctx;
885     OM_uint32 ret;
886 
887     GSSAPI_KRB5_INIT (&context);
888 
889     output_token->length = 0;
890     output_token->value  = NULL;
891 
892     if (context_handle == NULL) {
893 	*minor_status = 0;
894 	return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
895     }
896 
897     if (ret_flags)
898 	*ret_flags = 0;
899     if (time_rec)
900 	*time_rec = 0;
901 
902     if (target_name == GSS_C_NO_NAME) {
903 	if (actual_mech_type)
904 	    *actual_mech_type = GSS_C_NO_OID;
905 	*minor_status = 0;
906 	return GSS_S_BAD_NAME;
907     }
908 
909     if (mech_type != GSS_C_NO_OID &&
910 	!gss_oid_equal(mech_type, GSS_KRB5_MECHANISM))
911 	return GSS_S_BAD_MECH;
912 
913     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
914 	OM_uint32 ret1;
915 
916 	if (*context_handle != GSS_C_NO_CONTEXT) {
917 	    *minor_status = 0;
918 	    return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
919 	}
920 
921 	ret1 = _gsskrb5_create_ctx(minor_status,
922 				  context_handle,
923 				  context,
924 				  input_chan_bindings,
925 				  INITIATOR_START);
926 	if (ret1)
927 	    return ret1;
928     }
929 
930     if (*context_handle == GSS_C_NO_CONTEXT) {
931 	*minor_status = 0;
932 	return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
933     }
934 
935     ctx = (gsskrb5_ctx) *context_handle;
936 
937     HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
938 
939  again:
940     switch (ctx->state) {
941     case INITIATOR_START:
942 	ret = init_auth(minor_status,
943 			cred,
944 			ctx,
945 			context,
946 			target_name,
947 			mech_type,
948 			req_flags,
949 			time_req,
950 			input_token,
951 			actual_mech_type,
952 			output_token,
953 			ret_flags,
954 			time_rec);
955 	if (ret != GSS_S_COMPLETE)
956 	    break;
957 	/* FALL THOUGH */
958     case INITIATOR_RESTART:
959 	ret = init_auth_restart(minor_status,
960 				cred,
961 				ctx,
962 				context,
963 				req_flags,
964 				input_chan_bindings,
965 				input_token,
966 				actual_mech_type,
967 				output_token,
968 				ret_flags,
969 				time_rec);
970 	break;
971     case INITIATOR_WAIT_FOR_MUTAL:
972 	ret = repl_mutual(minor_status,
973 			  ctx,
974 			  context,
975 			  mech_type,
976 			  req_flags,
977 			  time_req,
978 			  input_chan_bindings,
979 			  input_token,
980 			  actual_mech_type,
981 			  output_token,
982 			  ret_flags,
983 			  time_rec);
984 	if (ctx->state == INITIATOR_RESTART)
985 	    goto again;
986 	break;
987     case INITIATOR_READY:
988 	/*
989 	 * If we get there, the caller have called
990 	 * gss_init_sec_context() one time too many.
991 	 */
992 	_gsskrb5_set_status(EINVAL, "init_sec_context "
993 			    "called one time too many");
994 	*minor_status = EINVAL;
995 	ret = GSS_S_BAD_STATUS;
996 	break;
997     default:
998 	_gsskrb5_set_status(EINVAL, "init_sec_context "
999 			    "invalid state %d for client",
1000 			    (int)ctx->state);
1001 	*minor_status = EINVAL;
1002 	ret = GSS_S_BAD_STATUS;
1003 	break;
1004     }
1005     HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
1006 
1007     /* destroy context in case of error */
1008     if (GSS_ERROR(ret)) {
1009 	OM_uint32 min2;
1010 	_gsskrb5_delete_sec_context(&min2, context_handle, GSS_C_NO_BUFFER);
1011     }
1012 
1013     return ret;
1014 
1015 }
1016