1 /*	$NetBSD: init_sec_context.c,v 1.5 2023/06/19 21:41:43 christos Exp $	*/
2 
3 /*
4  * Copyright (c) 1997 - 2008 Kungliga Tekniska Högskolan
5  * (Royal Institute of Technology, Stockholm, Sweden).
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  *
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  *
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the Institute nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #include "gsskrb5_locl.h"
37 
38 /*
39  * copy the addresses from `input_chan_bindings' (if any) to
40  * the auth context `ac'
41  */
42 
43 static OM_uint32
set_addresses(krb5_context context,krb5_auth_context ac,const gss_channel_bindings_t input_chan_bindings)44 set_addresses (krb5_context context,
45 	       krb5_auth_context ac,
46 	       const gss_channel_bindings_t input_chan_bindings)
47 {
48     /* Port numbers are expected to be in application_data.value,
49      * initator's port first */
50 
51     krb5_address initiator_addr, acceptor_addr;
52     krb5_error_code kret;
53 
54     if (input_chan_bindings == GSS_C_NO_CHANNEL_BINDINGS
55 	|| input_chan_bindings->application_data.length !=
56 	2 * sizeof(ac->local_port))
57 	return 0;
58 
59     memset(&initiator_addr, 0, sizeof(initiator_addr));
60     memset(&acceptor_addr, 0, sizeof(acceptor_addr));
61 
62     ac->local_port =
63 	*(int16_t *) input_chan_bindings->application_data.value;
64 
65     ac->remote_port =
66 	*((int16_t *) input_chan_bindings->application_data.value + 1);
67 
68     kret = _gsskrb5i_address_to_krb5addr(context,
69 					 input_chan_bindings->acceptor_addrtype,
70 					 &input_chan_bindings->acceptor_address,
71 					 ac->remote_port,
72 					 &acceptor_addr);
73     if (kret)
74 	return kret;
75 
76     kret = _gsskrb5i_address_to_krb5addr(context,
77 					 input_chan_bindings->initiator_addrtype,
78 					 &input_chan_bindings->initiator_address,
79 					 ac->local_port,
80 					 &initiator_addr);
81     if (kret) {
82 	krb5_free_address (context, &acceptor_addr);
83 	return kret;
84     }
85 
86     kret = krb5_auth_con_setaddrs(context,
87 				  ac,
88 				  &initiator_addr,  /* local address */
89 				  &acceptor_addr);  /* remote address */
90 
91     krb5_free_address (context, &initiator_addr);
92     krb5_free_address (context, &acceptor_addr);
93 
94 #if 0
95     free(input_chan_bindings->application_data.value);
96     input_chan_bindings->application_data.value = NULL;
97     input_chan_bindings->application_data.length = 0;
98 #endif
99 
100     return kret;
101 }
102 
103 OM_uint32
_gsskrb5_create_ctx(OM_uint32 * minor_status,gss_ctx_id_t * context_handle,krb5_context context,const gss_channel_bindings_t input_chan_bindings,enum gss_ctx_id_t_state state)104 _gsskrb5_create_ctx(
105         OM_uint32 * minor_status,
106 	gss_ctx_id_t * context_handle,
107 	krb5_context context,
108  	const gss_channel_bindings_t input_chan_bindings,
109  	enum gss_ctx_id_t_state state)
110 {
111     krb5_error_code kret;
112     gsskrb5_ctx ctx;
113 
114     *context_handle = NULL;
115 
116     ctx = malloc(sizeof(*ctx));
117     if (ctx == NULL) {
118 	*minor_status = ENOMEM;
119 	return GSS_S_FAILURE;
120     }
121     ctx->auth_context		= NULL;
122     ctx->deleg_auth_context	= NULL;
123     ctx->source			= NULL;
124     ctx->target			= NULL;
125     ctx->kcred			= NULL;
126     ctx->ccache			= NULL;
127     ctx->state			= state;
128     ctx->flags			= 0;
129     ctx->more_flags		= 0;
130     ctx->service_keyblock	= NULL;
131     ctx->ticket			= NULL;
132     krb5_data_zero(&ctx->fwd_data);
133     ctx->endtime		= 0;
134     ctx->order			= NULL;
135     ctx->crypto			= NULL;
136     HEIMDAL_MUTEX_init(&ctx->ctx_id_mutex);
137 
138     kret = krb5_auth_con_init (context, &ctx->auth_context);
139     if (kret) {
140 	*minor_status = kret;
141 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
142 	free(ctx);
143 	return GSS_S_FAILURE;
144     }
145 
146     kret = krb5_auth_con_init (context, &ctx->deleg_auth_context);
147     if (kret) {
148 	*minor_status = kret;
149 	krb5_auth_con_free(context, ctx->auth_context);
150 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
151 	free(ctx);
152 	return GSS_S_FAILURE;
153     }
154 
155     kret = set_addresses(context, ctx->auth_context, input_chan_bindings);
156     if (kret) {
157 	*minor_status = kret;
158 
159 	krb5_auth_con_free(context, ctx->auth_context);
160 	krb5_auth_con_free(context, ctx->deleg_auth_context);
161 
162 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
163 	free(ctx);
164 	return GSS_S_BAD_BINDINGS;
165     }
166 
167     kret = set_addresses(context, ctx->deleg_auth_context, input_chan_bindings);
168     if (kret) {
169 	*minor_status = kret;
170 
171 	krb5_auth_con_free(context, ctx->auth_context);
172 	krb5_auth_con_free(context, ctx->deleg_auth_context);
173 
174 	HEIMDAL_MUTEX_destroy(&ctx->ctx_id_mutex);
175 	free(ctx);
176 	return GSS_S_BAD_BINDINGS;
177     }
178 
179     /*
180      * We need a sequence number
181      */
182 
183     krb5_auth_con_addflags(context,
184 			   ctx->auth_context,
185 			   KRB5_AUTH_CONTEXT_DO_SEQUENCE |
186 			   KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED,
187 			   NULL);
188 
189     /*
190      * We need a sequence number
191      */
192 
193     krb5_auth_con_addflags(context,
194 			   ctx->deleg_auth_context,
195 			   KRB5_AUTH_CONTEXT_DO_SEQUENCE |
196 			   KRB5_AUTH_CONTEXT_CLEAR_FORWARDED_CRED,
197 			   NULL);
198 
199     *context_handle = (gss_ctx_id_t)ctx;
200 
201     return GSS_S_COMPLETE;
202 }
203 
204 
205 static OM_uint32
gsskrb5_get_creds(OM_uint32 * minor_status,krb5_context context,krb5_ccache ccache,gsskrb5_ctx ctx,gss_const_name_t target_name,OM_uint32 time_req,OM_uint32 * time_rec)206 gsskrb5_get_creds(
207         OM_uint32 * minor_status,
208 	krb5_context context,
209 	krb5_ccache ccache,
210 	gsskrb5_ctx ctx,
211 	gss_const_name_t target_name,
212 	OM_uint32 time_req,
213 	OM_uint32 * time_rec)
214 {
215     OM_uint32 ret;
216     krb5_error_code kret;
217     krb5_creds this_cred;
218     OM_uint32 lifetime_rec;
219 
220     if (ctx->target) {
221 	krb5_free_principal(context, ctx->target);
222 	ctx->target = NULL;
223     }
224     if (ctx->kcred) {
225 	krb5_free_creds(context, ctx->kcred);
226 	ctx->kcred = NULL;
227     }
228 
229     ret = _gsskrb5_canon_name(minor_status, context, target_name,
230                               &ctx->target);
231     if (ret)
232 	return ret;
233 
234     memset(&this_cred, 0, sizeof(this_cred));
235     this_cred.client = ctx->source;
236     this_cred.server = ctx->target;
237 
238     if (time_req && time_req != GSS_C_INDEFINITE) {
239 	krb5_timestamp ts;
240 
241 	krb5_timeofday (context, &ts);
242 	this_cred.times.endtime = ts + time_req;
243     } else {
244 	this_cred.times.endtime   = 0;
245     }
246 
247     this_cred.session.keytype = KEYTYPE_NULL;
248 
249     kret = krb5_get_credentials(context,
250 				0,
251 				ccache,
252 				&this_cred,
253 				&ctx->kcred);
254     if (kret) {
255 	*minor_status = kret;
256 	return GSS_S_FAILURE;
257     }
258 
259     ctx->endtime = ctx->kcred->times.endtime;
260 
261     ret = _gsskrb5_lifetime_left(minor_status, context,
262 				 ctx->endtime, &lifetime_rec);
263     if (ret) return ret;
264 
265     if (lifetime_rec == 0) {
266 	*minor_status = 0;
267 	return GSS_S_CONTEXT_EXPIRED;
268     }
269 
270     if (time_rec) *time_rec = lifetime_rec;
271 
272     return GSS_S_COMPLETE;
273 }
274 
275 static OM_uint32
gsskrb5_initiator_ready(OM_uint32 * minor_status,gsskrb5_ctx ctx,krb5_context context)276 gsskrb5_initiator_ready(
277 	OM_uint32 * minor_status,
278 	gsskrb5_ctx ctx,
279 	krb5_context context)
280 {
281     OM_uint32 ret;
282     int32_t seq_number;
283     int is_cfx = 0;
284     OM_uint32 flags = ctx->flags;
285 
286     krb5_free_creds(context, ctx->kcred);
287     ctx->kcred = NULL;
288 
289     if (ctx->more_flags & CLOSE_CCACHE)
290 	krb5_cc_close(context, ctx->ccache);
291     ctx->ccache = NULL;
292 
293     krb5_auth_con_getremoteseqnumber (context, ctx->auth_context, &seq_number);
294 
295     _gsskrb5i_is_cfx(context, ctx, 0);
296     is_cfx = (ctx->more_flags & IS_CFX);
297 
298     ret = _gssapi_msg_order_create(minor_status,
299 				   &ctx->order,
300 				   _gssapi_msg_order_f(flags),
301 				   seq_number, 0, is_cfx);
302     if (ret) return ret;
303 
304     ctx->state	= INITIATOR_READY;
305     ctx->more_flags	|= OPEN;
306 
307     return GSS_S_COMPLETE;
308 }
309 
310 /*
311  * handle delegated creds in init-sec-context
312  */
313 
314 static void
do_delegation(krb5_context context,krb5_auth_context ac,krb5_ccache ccache,krb5_creds * cred,krb5_const_principal name,krb5_data * fwd_data,uint32_t flagmask,uint32_t * flags)315 do_delegation (krb5_context context,
316 	       krb5_auth_context ac,
317 	       krb5_ccache ccache,
318 	       krb5_creds *cred,
319 	       krb5_const_principal name,
320 	       krb5_data *fwd_data,
321 	       uint32_t flagmask,
322 	       uint32_t *flags)
323 {
324     krb5_creds creds;
325     KDCOptions fwd_flags;
326     krb5_error_code kret;
327 
328     memset (&creds, 0, sizeof(creds));
329     krb5_data_zero (fwd_data);
330 
331     kret = krb5_cc_get_principal(context, ccache, &creds.client);
332     if (kret)
333 	goto out;
334 
335     kret = krb5_make_principal(context,
336 			       &creds.server,
337 			       creds.client->realm,
338 			       KRB5_TGS_NAME,
339 			       creds.client->realm,
340 			       NULL);
341     if (kret)
342 	goto out;
343 
344     creds.times.endtime = 0;
345 
346     memset(&fwd_flags, 0, sizeof(fwd_flags));
347     fwd_flags.forwarded = 1;
348     fwd_flags.forwardable = 1;
349 
350     if (name->name.name_string.len < 2)
351 	goto out;
352 
353     kret = krb5_get_forwarded_creds(context,
354 				    ac,
355 				    ccache,
356 				    KDCOptions2int(fwd_flags),
357 				    name->name.name_string.val[1],
358 				    &creds,
359 				    fwd_data);
360 
361  out:
362     if (kret)
363 	*flags &= ~flagmask;
364     else
365 	*flags |= flagmask;
366 
367     if (creds.client)
368 	krb5_free_principal(context, creds.client);
369     if (creds.server)
370 	krb5_free_principal(context, creds.server);
371 }
372 
373 /*
374  * first stage of init-sec-context
375  */
376 
377 static OM_uint32
init_auth(OM_uint32 * minor_status,gsskrb5_cred cred,gsskrb5_ctx ctx,krb5_context context,gss_const_name_t name,const gss_OID mech_type,OM_uint32 req_flags,OM_uint32 time_req,const gss_buffer_t input_token,gss_OID * actual_mech_type,gss_buffer_t output_token,OM_uint32 * ret_flags,OM_uint32 * time_rec)378 init_auth
379 (OM_uint32 * minor_status,
380  gsskrb5_cred cred,
381  gsskrb5_ctx ctx,
382  krb5_context context,
383  gss_const_name_t name,
384  const gss_OID mech_type,
385  OM_uint32 req_flags,
386  OM_uint32 time_req,
387  const gss_buffer_t input_token,
388  gss_OID * actual_mech_type,
389  gss_buffer_t output_token,
390  OM_uint32 * ret_flags,
391  OM_uint32 * time_rec
392     )
393 {
394     OM_uint32 ret = GSS_S_FAILURE;
395     krb5_error_code kret;
396     krb5_data fwd_data;
397     OM_uint32 lifetime_rec;
398 
399     krb5_data_zero(&fwd_data);
400 
401     *minor_status = 0;
402 
403     if (actual_mech_type)
404 	*actual_mech_type = GSS_KRB5_MECHANISM;
405 
406     if (cred == NULL) {
407 	kret = krb5_cc_default (context, &ctx->ccache);
408 	if (kret) {
409 	    *minor_status = kret;
410 	    ret = GSS_S_FAILURE;
411 	    goto failure;
412 	}
413 	ctx->more_flags |= CLOSE_CCACHE;
414     } else
415 	ctx->ccache = cred->ccache;
416 
417     kret = krb5_cc_get_principal (context, ctx->ccache, &ctx->source);
418     if (kret) {
419 	*minor_status = kret;
420 	ret = GSS_S_FAILURE;
421 	goto failure;
422     }
423 
424     /*
425      * This is hideous glue for (NFS) clients that wants to limit the
426      * available enctypes to what it can support (encryption in
427      * kernel).
428      */
429     if (cred && cred->enctypes)
430 	krb5_set_default_in_tkt_etypes(context, cred->enctypes);
431 
432     ret = gsskrb5_get_creds(minor_status, context, ctx->ccache,
433 			    ctx, name, time_req, time_rec);
434     if (ret)
435 	goto failure;
436 
437     ctx->endtime = ctx->kcred->times.endtime;
438 
439     ret = _gss_DES3_get_mic_compat(minor_status, ctx, context);
440     if (ret)
441 	goto failure;
442 
443     ret = _gsskrb5_lifetime_left(minor_status,
444 				 context,
445 				 ctx->endtime,
446 				 &lifetime_rec);
447     if (ret)
448 	goto failure;
449 
450     if (lifetime_rec == 0) {
451 	*minor_status = 0;
452 	ret = GSS_S_CONTEXT_EXPIRED;
453 	goto failure;
454     }
455 
456     krb5_auth_con_setkey(context,
457 			 ctx->auth_context,
458 			 &ctx->kcred->session);
459 
460     kret = krb5_auth_con_generatelocalsubkey(context,
461 					     ctx->auth_context,
462 					     &ctx->kcred->session);
463     if(kret) {
464 	*minor_status = kret;
465 	ret = GSS_S_FAILURE;
466 	goto failure;
467     }
468 
469     return GSS_S_COMPLETE;
470 
471 failure:
472     if (ctx->ccache && (ctx->more_flags & CLOSE_CCACHE))
473 	krb5_cc_close(context, ctx->ccache);
474     ctx->ccache = NULL;
475 
476     return ret;
477 
478 }
479 
480 static OM_uint32
init_auth_restart(OM_uint32 * minor_status,gsskrb5_cred cred,gsskrb5_ctx ctx,krb5_context context,OM_uint32 req_flags,const gss_channel_bindings_t input_chan_bindings,const gss_buffer_t input_token,gss_OID * actual_mech_type,gss_buffer_t output_token,OM_uint32 * ret_flags,OM_uint32 * time_rec)481 init_auth_restart
482 (OM_uint32 * minor_status,
483  gsskrb5_cred cred,
484  gsskrb5_ctx ctx,
485  krb5_context context,
486  OM_uint32 req_flags,
487  const gss_channel_bindings_t input_chan_bindings,
488  const gss_buffer_t input_token,
489  gss_OID * actual_mech_type,
490  gss_buffer_t output_token,
491  OM_uint32 * ret_flags,
492  OM_uint32 * time_rec
493     )
494 {
495     OM_uint32 ret = GSS_S_FAILURE;
496     krb5_error_code kret;
497     krb5_flags ap_options;
498     krb5_data outbuf;
499     uint32_t flags;
500     krb5_data authenticator;
501     Checksum cksum;
502     krb5_enctype enctype;
503     krb5_data fwd_data, timedata;
504     int32_t offset = 0, oldoffset = 0;
505     uint32_t flagmask;
506 
507     krb5_data_zero(&outbuf);
508     krb5_data_zero(&fwd_data);
509 
510     *minor_status = 0;
511 
512     /*
513      * If the credential doesn't have ok-as-delegate, check if there
514      * is a realm setting and use that.
515      */
516     if (!ctx->kcred->flags.b.ok_as_delegate) {
517 	krb5_data data;
518 
519 	ret = krb5_cc_get_config(context, ctx->ccache, NULL,
520 				 "realm-config", &data);
521 	if (ret == 0) {
522 	    /* XXX 1 is use ok-as-delegate */
523 	    if (data.length < 1 || ((((unsigned char *)data.data)[0]) & 1) == 0)
524 		req_flags &= ~(GSS_C_DELEG_FLAG|GSS_C_DELEG_POLICY_FLAG);
525 	    krb5_data_free(&data);
526 	}
527     }
528 
529     flagmask = 0;
530 
531     /* if we used GSS_C_DELEG_POLICY_FLAG, trust KDC */
532     if ((req_flags & GSS_C_DELEG_POLICY_FLAG)
533 	&& ctx->kcred->flags.b.ok_as_delegate)
534 	flagmask |= GSS_C_DELEG_FLAG | GSS_C_DELEG_POLICY_FLAG;
535     /* if there still is a GSS_C_DELEG_FLAG, use that */
536     if (req_flags & GSS_C_DELEG_FLAG)
537 	flagmask |= GSS_C_DELEG_FLAG;
538 
539 
540     flags = 0;
541     ap_options = 0;
542     if (flagmask & GSS_C_DELEG_FLAG) {
543 	do_delegation (context,
544 		       ctx->deleg_auth_context,
545 		       ctx->ccache, ctx->kcred, ctx->target,
546 		       &fwd_data, flagmask, &flags);
547     }
548 
549     if (req_flags & GSS_C_MUTUAL_FLAG) {
550 	flags |= GSS_C_MUTUAL_FLAG;
551 	ap_options |= AP_OPTS_MUTUAL_REQUIRED;
552     }
553 
554     if (req_flags & GSS_C_REPLAY_FLAG)
555 	flags |= GSS_C_REPLAY_FLAG;
556     if (req_flags & GSS_C_SEQUENCE_FLAG)
557 	flags |= GSS_C_SEQUENCE_FLAG;
558 #if 0
559     if (req_flags & GSS_C_ANON_FLAG)
560 	;                               /* XXX */
561 #endif
562     if (req_flags & GSS_C_DCE_STYLE) {
563 	/* GSS_C_DCE_STYLE implies GSS_C_MUTUAL_FLAG */
564 	flags |= GSS_C_DCE_STYLE | GSS_C_MUTUAL_FLAG;
565 	ap_options |= AP_OPTS_MUTUAL_REQUIRED;
566     }
567     if (req_flags & GSS_C_IDENTIFY_FLAG)
568 	flags |= GSS_C_IDENTIFY_FLAG;
569     if (req_flags & GSS_C_EXTENDED_ERROR_FLAG)
570 	flags |= GSS_C_EXTENDED_ERROR_FLAG;
571 
572     if (req_flags & GSS_C_CONF_FLAG) {
573 	flags |= GSS_C_CONF_FLAG;
574     }
575     if (req_flags & GSS_C_INTEG_FLAG) {
576 	flags |= GSS_C_INTEG_FLAG;
577     }
578     if (cred == NULL || !(cred->cred_flags & GSS_CF_NO_CI_FLAGS)) {
579 	flags |= GSS_C_CONF_FLAG;
580 	flags |= GSS_C_INTEG_FLAG;
581     }
582     flags |= GSS_C_TRANS_FLAG;
583 
584     if (ret_flags)
585 	*ret_flags = flags;
586     ctx->flags = flags;
587     ctx->more_flags |= LOCAL;
588 
589     ret = _gsskrb5_create_8003_checksum (minor_status,
590 					 input_chan_bindings,
591 					 flags,
592 					 &fwd_data,
593 					 &cksum);
594     krb5_data_free (&fwd_data);
595     if (ret)
596 	goto failure;
597 
598     enctype = ctx->auth_context->keyblock->keytype;
599 
600     ret = krb5_cc_get_config(context, ctx->ccache, ctx->target,
601 			     "time-offset", &timedata);
602     if (ret == 0) {
603 	if (timedata.length == 4) {
604 	    const u_char *p = timedata.data;
605             if (p[0] < 128) {
606                 offset = (p[0] <<24) | (p[1] << 16) | (p[2] << 8) | (p[3] << 0);
607             } else {
608                 /*
609                  * (p[0] << 24), if p[0] > 127 -> offset is negative, but *p is
610                  * positive, so this is overflow -- overflow we want, but UBSAN
611                  * flags it.
612                  *
613                  * NOTE: We assume the platform is a twos-complement platform.
614                  */
615                 offset = INT32_MIN;
616                 offset |= ((p[0] & 0x7f) <<24) | (p[1] << 16) | (p[2] << 8) | (p[3] << 0);
617             }
618 	}
619 	krb5_data_free(&timedata);
620     }
621 
622     if (offset) {
623 	krb5_get_kdc_sec_offset (context, &oldoffset, NULL);
624 	krb5_set_kdc_sec_offset (context, offset, -1);
625     }
626 
627     kret = _krb5_build_authenticator(context,
628 				     ctx->auth_context,
629 				     enctype,
630 				     ctx->kcred,
631 				     &cksum,
632 				     &authenticator,
633 				     KRB5_KU_AP_REQ_AUTH);
634 
635     if (kret) {
636 	if (offset)
637 	    krb5_set_kdc_sec_offset (context, oldoffset, -1);
638 	*minor_status = kret;
639 	ret = GSS_S_FAILURE;
640 	goto failure;
641     }
642 
643     kret = krb5_build_ap_req (context,
644 			      enctype,
645 			      ctx->kcred,
646 			      ap_options,
647 			      authenticator,
648 			      &outbuf);
649     if (offset)
650 	krb5_set_kdc_sec_offset (context, oldoffset, -1);
651     if (kret) {
652 	*minor_status = kret;
653 	ret = GSS_S_FAILURE;
654 	goto failure;
655     }
656 
657     if (flags & GSS_C_DCE_STYLE) {
658 	output_token->value = outbuf.data;
659 	output_token->length = outbuf.length;
660     } else {
661         ret = _gsskrb5_encapsulate (minor_status, &outbuf, output_token,
662 				    (u_char *)(intptr_t)"\x01\x00",
663 				    GSS_KRB5_MECHANISM);
664 	krb5_data_free (&outbuf);
665 	if (ret)
666 	    goto failure;
667     }
668 
669     free_Checksum(&cksum);
670 
671     if (flags & GSS_C_MUTUAL_FLAG) {
672 	ctx->state = INITIATOR_WAIT_FOR_MUTAL;
673 	return GSS_S_CONTINUE_NEEDED;
674     }
675 
676     return gsskrb5_initiator_ready(minor_status, ctx, context);
677 failure:
678     if (ctx->ccache && (ctx->more_flags & CLOSE_CCACHE))
679 	krb5_cc_close(context, ctx->ccache);
680     ctx->ccache = NULL;
681 
682     return ret;
683 }
684 
685 static krb5_error_code
handle_error_packet(krb5_context context,gsskrb5_ctx ctx,krb5_data indata)686 handle_error_packet(krb5_context context,
687 		    gsskrb5_ctx ctx,
688 		    krb5_data indata)
689 {
690     krb5_error_code kret;
691     KRB_ERROR error;
692 
693     kret = krb5_rd_error(context, &indata, &error);
694     if (kret == 0) {
695 	kret = krb5_error_from_rd_error(context, &error, NULL);
696 
697 	/* save the time skrew for this host */
698 	if (kret == KRB5KRB_AP_ERR_SKEW) {
699 	    krb5_data timedata;
700 	    unsigned char p[4];
701 	    int32_t t = error.stime - time(NULL);
702 
703 	    p[0] = (t >> 24) & 0xFF;
704 	    p[1] = (t >> 16) & 0xFF;
705 	    p[2] = (t >> 8)  & 0xFF;
706 	    p[3] = (t >> 0)  & 0xFF;
707 
708 	    timedata.data = p;
709 	    timedata.length = sizeof(p);
710 
711 	    krb5_cc_set_config(context, ctx->ccache, ctx->target,
712 			       "time-offset", &timedata);
713 
714 	    if ((ctx->more_flags & RETRIED) == 0)
715 		 ctx->state = INITIATOR_RESTART;
716 	    ctx->more_flags |= RETRIED;
717 	}
718 	free_KRB_ERROR (&error);
719     }
720     return kret;
721 }
722 
723 
724 static OM_uint32
repl_mutual(OM_uint32 * minor_status,gsskrb5_ctx ctx,krb5_context context,const gss_OID mech_type,OM_uint32 req_flags,OM_uint32 time_req,const gss_channel_bindings_t input_chan_bindings,const gss_buffer_t input_token,gss_OID * actual_mech_type,gss_buffer_t output_token,OM_uint32 * ret_flags,OM_uint32 * time_rec)725 repl_mutual
726 (OM_uint32 * minor_status,
727  gsskrb5_ctx ctx,
728  krb5_context context,
729  const gss_OID mech_type,
730  OM_uint32 req_flags,
731  OM_uint32 time_req,
732  const gss_channel_bindings_t input_chan_bindings,
733  const gss_buffer_t input_token,
734  gss_OID * actual_mech_type,
735  gss_buffer_t output_token,
736  OM_uint32 * ret_flags,
737  OM_uint32 * time_rec
738     )
739 {
740     OM_uint32 ret;
741     krb5_error_code kret;
742     krb5_data indata;
743     krb5_ap_rep_enc_part *repl;
744 
745     output_token->length = 0;
746     output_token->value = NULL;
747 
748     if (actual_mech_type)
749 	*actual_mech_type = GSS_KRB5_MECHANISM;
750 
751     if (IS_DCE_STYLE(ctx)) {
752 	/* There is no OID wrapping. */
753 	indata.length	= input_token->length;
754 	indata.data	= input_token->value;
755 	kret = krb5_rd_rep(context,
756 			   ctx->auth_context,
757 			   &indata,
758 			   &repl);
759 	if (kret) {
760 	    ret = _gsskrb5_decapsulate(minor_status,
761 				       input_token,
762 				       &indata,
763 				       "\x03\x00",
764 				       GSS_KRB5_MECHANISM);
765 	    if (ret == GSS_S_COMPLETE) {
766 		*minor_status = handle_error_packet(context, ctx, indata);
767 	    } else {
768 		*minor_status = kret;
769 	    }
770 	    return GSS_S_FAILURE;
771 	}
772     } else {
773 	ret = _gsskrb5_decapsulate (minor_status,
774 				    input_token,
775 				    &indata,
776 				    "\x02\x00",
777 				    GSS_KRB5_MECHANISM);
778 	if (ret == GSS_S_DEFECTIVE_TOKEN) {
779 	    /* check if there is an error token sent instead */
780 	    ret = _gsskrb5_decapsulate (minor_status,
781 					input_token,
782 					&indata,
783 					"\x03\x00",
784 					GSS_KRB5_MECHANISM);
785 	    if (ret == GSS_S_COMPLETE) {
786 		*minor_status = handle_error_packet(context, ctx, indata);
787 		return GSS_S_FAILURE;
788 	    }
789 	}
790 	kret = krb5_rd_rep (context,
791 			    ctx->auth_context,
792 			    &indata,
793 			    &repl);
794 	if (kret) {
795 	    *minor_status = kret;
796 	    return GSS_S_FAILURE;
797 	}
798     }
799 
800     krb5_free_ap_rep_enc_part (context,
801 			       repl);
802 
803     *minor_status = 0;
804     if (time_rec)
805         _gsskrb5_lifetime_left(minor_status,
806                                context,
807                                ctx->endtime,
808                                time_rec);
809     if (ret_flags)
810 	*ret_flags = ctx->flags;
811 
812     if (req_flags & GSS_C_DCE_STYLE) {
813 	int32_t local_seq, remote_seq;
814 	krb5_data outbuf;
815 
816 	/*
817 	 * So DCE_STYLE is strange. The client echos the seq number
818 	 * that the server used in the server's mk_rep in its own
819 	 * mk_rep(). After when done, it resets to it's own seq number
820 	 * for the gss_wrap calls.
821 	 */
822 
823 	krb5_auth_con_getremoteseqnumber(context, ctx->auth_context, &remote_seq);
824 	krb5_auth_con_getlocalseqnumber(context, ctx->auth_context, &local_seq);
825 	krb5_auth_con_setlocalseqnumber(context, ctx->auth_context, remote_seq);
826 
827 	kret = krb5_mk_rep(context, ctx->auth_context, &outbuf);
828 	if (kret) {
829 	    *minor_status = kret;
830 	    return GSS_S_FAILURE;
831 	}
832 
833 	/* reset local seq number */
834 	krb5_auth_con_setlocalseqnumber(context, ctx->auth_context, local_seq);
835 
836 	output_token->length = outbuf.length;
837 	output_token->value  = outbuf.data;
838     }
839 
840     return gsskrb5_initiator_ready(minor_status, ctx, context);
841 }
842 
843 /*
844  * gss_init_sec_context
845  */
846 
_gsskrb5_init_sec_context(OM_uint32 * minor_status,gss_const_cred_id_t cred_handle,gss_ctx_id_t * context_handle,gss_const_name_t target_name,const gss_OID mech_type,OM_uint32 req_flags,OM_uint32 time_req,const gss_channel_bindings_t input_chan_bindings,const gss_buffer_t input_token,gss_OID * actual_mech_type,gss_buffer_t output_token,OM_uint32 * ret_flags,OM_uint32 * time_rec)847 OM_uint32 GSSAPI_CALLCONV _gsskrb5_init_sec_context
848 (OM_uint32 * minor_status,
849  gss_const_cred_id_t cred_handle,
850  gss_ctx_id_t * context_handle,
851  gss_const_name_t target_name,
852  const gss_OID mech_type,
853  OM_uint32 req_flags,
854  OM_uint32 time_req,
855  const gss_channel_bindings_t input_chan_bindings,
856  const gss_buffer_t input_token,
857  gss_OID * actual_mech_type,
858  gss_buffer_t output_token,
859  OM_uint32 * ret_flags,
860  OM_uint32 * time_rec
861     )
862 {
863     krb5_context context;
864     gsskrb5_cred cred = (gsskrb5_cred)cred_handle;
865     gsskrb5_ctx ctx;
866     OM_uint32 ret;
867 
868     GSSAPI_KRB5_INIT (&context);
869 
870     output_token->length = 0;
871     output_token->value  = NULL;
872 
873     if (context_handle == NULL) {
874 	*minor_status = 0;
875 	return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
876     }
877 
878     if (ret_flags)
879 	*ret_flags = 0;
880     if (time_rec)
881 	*time_rec = 0;
882 
883     if (target_name == GSS_C_NO_NAME) {
884 	if (actual_mech_type)
885 	    *actual_mech_type = GSS_C_NO_OID;
886 	*minor_status = 0;
887 	return GSS_S_BAD_NAME;
888     }
889 
890     if (mech_type != GSS_C_NO_OID &&
891 	!gss_oid_equal(mech_type, GSS_KRB5_MECHANISM))
892 	return GSS_S_BAD_MECH;
893 
894     if (input_token == GSS_C_NO_BUFFER || input_token->length == 0) {
895 	OM_uint32 ret1;
896 
897 	if (*context_handle != GSS_C_NO_CONTEXT) {
898 	    *minor_status = 0;
899 	    return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
900 	}
901 
902 	ret1 = _gsskrb5_create_ctx(minor_status,
903 				  context_handle,
904 				  context,
905 				  input_chan_bindings,
906 				  INITIATOR_START);
907 	if (ret1)
908 	    return ret1;
909     }
910 
911     if (*context_handle == GSS_C_NO_CONTEXT) {
912 	*minor_status = 0;
913 	return GSS_S_FAILURE | GSS_S_CALL_BAD_STRUCTURE;
914     }
915 
916     ctx = (gsskrb5_ctx) *context_handle;
917 
918     HEIMDAL_MUTEX_lock(&ctx->ctx_id_mutex);
919 
920  again:
921     switch (ctx->state) {
922     case INITIATOR_START:
923 	ret = init_auth(minor_status,
924 			cred,
925 			ctx,
926 			context,
927 			target_name,
928 			mech_type,
929 			req_flags,
930 			time_req,
931 			input_token,
932 			actual_mech_type,
933 			output_token,
934 			ret_flags,
935 			time_rec);
936 	if (ret != GSS_S_COMPLETE)
937 	    break;
938 	/* FALLTHROUGH */
939     case INITIATOR_RESTART:
940 	ret = init_auth_restart(minor_status,
941 				cred,
942 				ctx,
943 				context,
944 				req_flags,
945 				input_chan_bindings,
946 				input_token,
947 				actual_mech_type,
948 				output_token,
949 				ret_flags,
950 				time_rec);
951 	break;
952     case INITIATOR_WAIT_FOR_MUTAL:
953 	ret = repl_mutual(minor_status,
954 			  ctx,
955 			  context,
956 			  mech_type,
957 			  req_flags,
958 			  time_req,
959 			  input_chan_bindings,
960 			  input_token,
961 			  actual_mech_type,
962 			  output_token,
963 			  ret_flags,
964 			  time_rec);
965 	if (ctx->state == INITIATOR_RESTART)
966 	    goto again;
967 	break;
968     case INITIATOR_READY:
969 	/*
970 	 * If we get there, the caller have called
971 	 * gss_init_sec_context() one time too many.
972 	 */
973 	_gsskrb5_set_status(EINVAL, "init_sec_context "
974 			    "called one time too many");
975 	*minor_status = EINVAL;
976 	ret = GSS_S_BAD_STATUS;
977 	break;
978     default:
979 	_gsskrb5_set_status(EINVAL, "init_sec_context "
980 			    "invalid state %d for client",
981 			    (int)ctx->state);
982 	*minor_status = EINVAL;
983 	ret = GSS_S_BAD_STATUS;
984 	break;
985     }
986     HEIMDAL_MUTEX_unlock(&ctx->ctx_id_mutex);
987 
988     /* destroy context in case of error */
989     if (GSS_ERROR(ret)) {
990 	OM_uint32 min2;
991 	_gsskrb5_delete_sec_context(&min2, context_handle, GSS_C_NO_BUFFER);
992     }
993 
994     return ret;
995 
996 }
997