xref: /titanic_52/usr/src/lib/rpcsec_gss/rpcsec_gss.c (revision 47911a7d5f24c2fc37e7b5bcc696fe32e750c16c)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"
28 
29 
30 /*
31  * Copyright 1993 OpenVision Technologies, Inc., All Rights Reserved.
32  *
33  * $Header:
34  * /afs/gza.com/product/secure/rel-eng/src/1.1/rpc/RCS/auth_gssapi.c,v
35  * 1.14 1995/03/22 22:07:55 jik Exp $
36  */
37 
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <strings.h>
41 #include <errno.h>
42 #include <pthread.h>
43 #include <thread.h>
44 #include <syslog.h>
45 #include <gssapi/gssapi.h>
46 #include <rpc/rpc.h>
47 #include <rpc/rpcsec_defs.h>
48 
49 static void 	rpc_gss_nextverf();
50 static bool_t 	rpc_gss_marshall();
51 static bool_t	rpc_gss_validate();
52 static bool_t	rpc_gss_refresh();
53 static void	rpc_gss_destroy();
54 static void	rpc_gss_destroy_pvt();
55 static bool_t	rpc_gss_seccreate_pvt();
56 static bool_t	validate_seqwin();
57 
58 /*
59  * Globals that should have header files but don't.
60  */
61 extern bool_t	xdr_opaque_auth(XDR *, struct opaque_auth *);
62 extern int	_thr_main(void);
63 extern void	*_pthread_getspecific(pthread_key_t key);
64 typedef void	(*PFrV) (void *);
65 extern int	_thr_keycreate_once(thread_key_t *pkey, PFrV destructor);
66 extern int	_thr_setspecific(unsigned int key, void *value);
67 
68 
69 static struct auth_ops rpc_gss_ops = {
70 	rpc_gss_nextverf,
71 	rpc_gss_marshall,
72 	rpc_gss_validate,
73 	rpc_gss_refresh,
74 	rpc_gss_destroy
75 };
76 
77 /*
78  * Private data for RPCSEC_GSS.
79  */
80 typedef struct _rpc_gss_data {
81 	bool_t			established;	/* TRUE when established */
82 	CLIENT			*clnt;		/* associated client handle */
83 	uint_t			version;	/* RPCSEC version */
84 	gss_ctx_id_t		context;	/* GSS context id */
85 	gss_buffer_desc		ctx_handle;	/* RPCSEC context handle */
86 	uint_t			seq_num;	/* last sequence number rcvd */
87 	gss_cred_id_t		my_cred;	/* GSS credentials */
88 	OM_uint32		qop;		/* requested QOP */
89 	rpc_gss_service_t	service;	/* requested service */
90 	uint_t			gss_proc;	/* GSS control procedure */
91 	gss_name_t		target_name;	/* target server */
92 	int			req_flags;	/* GSS request bits */
93 	gss_OID			mech_type;	/* GSS mechanism */
94 	OM_uint32		time_req;	/* requested cred lifetime */
95 	bool_t			invalid;	/* can't use this any more */
96 	OM_uint32		seq_window;	/* server sequence window */
97 	struct opaque_auth	*verifier;  /* rpc reply verifier saved for */
98 					    /* validating the sequence window */
99 	gss_channel_bindings_t	icb;
100 } rpc_gss_data;
101 #define	AUTH_PRIVATE(auth) ((rpc_gss_data *)auth->ah_private)
102 
103 /*
104  * Create a context.
105  */
106 AUTH *
107 __rpc_gss_seccreate(clnt, server_name, mech, service, qop, options_req,
108 								options_ret)
109 	CLIENT			*clnt;		/* associated client handle */
110 	char			*server_name;	/* target server */
111 	char			*mech;		/* security mechanism */
112 	rpc_gss_service_t	service;	/* security service */
113 	char			*qop;		/* requested QOP */
114 	rpc_gss_options_req_t	*options_req;	/* requested options */
115 	rpc_gss_options_ret_t	*options_ret;	/* returned options */
116 {
117 	OM_uint32		gssstat;
118 	OM_uint32		minor_stat;
119 	gss_name_t		target_name;
120 	gss_OID			mech_type;
121 	OM_uint32		ret_flags;
122 	OM_uint32		time_rec;
123 	gss_buffer_desc		input_name;
124 	AUTH			*auth = NULL;
125 	rpc_gss_data		*ap = NULL;
126 	OM_uint32		qop_num;
127 
128 	/*
129 	 * convert ascii strings to GSS values
130 	 */
131 	if (!__rpc_gss_qop_to_num(qop, mech, &qop_num)) {
132 		return (NULL);
133 	}
134 
135 	if (!__rpc_gss_mech_to_oid(mech, &mech_type)) {
136 		return (NULL);
137 	}
138 
139 	/*
140 	 * convert name to GSS internal type
141 	 */
142 	input_name.value = server_name;
143 	input_name.length = strlen(server_name);
144 	gssstat = gss_import_name(&minor_stat, &input_name,
145 				(gss_OID)GSS_C_NT_HOSTBASED_SERVICE,
146 				&target_name);
147 	if (gssstat != GSS_S_COMPLETE) {
148 		rpc_gss_err.rpc_gss_error = RPC_GSS_ER_SYSTEMERROR;
149 		rpc_gss_err.system_error = ENOMEM;
150 		return (NULL);
151 	}
152 
153 	/*
154 	 * Create AUTH handle.  Save the necessary interface information
155 	 * so that the client can refresh the handle later if needed.
156 	 */
157 	if ((auth = (AUTH *) malloc(sizeof (*auth))) != NULL)
158 		ap = (rpc_gss_data *) malloc(sizeof (*ap));
159 	if (auth == NULL || ap == NULL) {
160 		rpc_gss_err.rpc_gss_error = RPC_GSS_ER_SYSTEMERROR;
161 		rpc_gss_err.system_error = ENOMEM;
162 		if (auth != NULL)
163 			free((char *)auth);
164 		(void) gss_release_name(&minor_stat, &target_name);
165 		return (NULL);
166 	}
167 
168 	memset((char *)ap, 0, sizeof (*ap));
169 	ap->clnt = clnt;
170 	ap->version = RPCSEC_GSS_VERSION;
171 	if (options_req != NULL) {
172 		ap->my_cred = options_req->my_cred;
173 		ap->req_flags = options_req->req_flags;
174 		ap->time_req = options_req->time_req;
175 		ap->icb = options_req->input_channel_bindings;
176 	} else {
177 		ap->my_cred = GSS_C_NO_CREDENTIAL;
178 		ap->req_flags = GSS_C_MUTUAL_FLAG;
179 		ap->time_req = 0;
180 		ap->icb = NULL;
181 	}
182 	if ((ap->service = service) == rpc_gss_svc_default)
183 		ap->service = rpc_gss_svc_integrity;
184 	ap->qop = qop_num;
185 	ap->target_name = target_name;
186 	ap->mech_type = mech_type;
187 
188 	/*
189 	 * Now invoke the real interface that sets up the context from
190 	 * the information stashed away in the private data.
191 	 */
192 	if (!rpc_gss_seccreate_pvt(&gssstat, &minor_stat, auth, ap,
193 				&mech_type, &ret_flags, &time_rec)) {
194 		if (ap->target_name)
195 			(void) gss_release_name(&minor_stat, &ap->target_name);
196 		free((char *)ap);
197 		free((char *)auth);
198 		return (NULL);
199 	}
200 
201 	/*
202 	 * Make sure that the requested service is supported.  In all
203 	 * cases, integrity service must be available.
204 	 */
205 	if ((ap->service == rpc_gss_svc_privacy &&
206 					!(ret_flags & GSS_C_CONF_FLAG)) ||
207 			!(ret_flags & GSS_C_INTEG_FLAG)) {
208 		rpc_gss_destroy(auth);
209 		rpc_gss_err.rpc_gss_error = RPC_GSS_ER_SYSTEMERROR;
210 		rpc_gss_err.system_error = EPROTONOSUPPORT;
211 		return (NULL);
212 	}
213 
214 	/*
215 	 * return option values if requested
216 	 */
217 	if (options_ret != NULL) {
218 		char	*s;
219 
220 		options_ret->major_status = gssstat;
221 		options_ret->minor_status = minor_stat;
222 		options_ret->rpcsec_version = ap->version;
223 		options_ret->ret_flags = ret_flags;
224 		options_ret->time_ret = time_rec;
225 		options_ret->gss_context = ap->context;
226 		if ((s = __rpc_gss_oid_to_mech(mech_type)) != NULL)
227 			strcpy(options_ret->actual_mechanism, s);
228 		else
229 			options_ret->actual_mechanism[0] = '\0';
230 	}
231 	return (auth);
232 }
233 
234 /*
235  * Private interface to create a context.  This is the interface
236  * that's invoked when the context has to be refreshed.
237  */
238 static bool_t
239 rpc_gss_seccreate_pvt(gssstat, minor_stat, auth, ap, actual_mech_type,
240 						ret_flags, time_rec)
241 	OM_uint32		*gssstat;
242 	OM_uint32		*minor_stat;
243 	AUTH			*auth;
244 	rpc_gss_data		*ap;
245 	gss_OID			*actual_mech_type;
246 	OM_uint32		*ret_flags;
247 	OM_uint32		*time_rec;
248 {
249 	CLIENT			*clnt = ap->clnt;
250 	AUTH			*save_auth;
251 	enum clnt_stat		callstat;
252 	rpc_gss_init_arg	call_arg;
253 	rpc_gss_init_res	call_res;
254 	gss_buffer_desc		*input_token_p, input_token;
255 	bool_t			free_results = FALSE;
256 
257 	/*
258 	 * initialize error
259 	 */
260 	memset(&rpc_createerr, 0, sizeof (rpc_createerr));
261 
262 	/*
263 	 * (re)initialize AUTH handle and private data.
264 	 */
265 	memset((char *)auth, 0, sizeof (*auth));
266 	auth->ah_ops = &rpc_gss_ops;
267 	auth->ah_private = (caddr_t)ap;
268 	auth->ah_cred.oa_flavor = RPCSEC_GSS;
269 
270 	ap->established = FALSE;
271 	ap->ctx_handle.length = 0;
272 	ap->ctx_handle.value = NULL;
273 	ap->context = GSS_C_NO_CONTEXT;
274 	ap->seq_num = 0;
275 	ap->gss_proc = RPCSEC_GSS_INIT;
276 
277 	/*
278 	 * should not change clnt->cl_auth at this time, so save
279 	 * old handle
280 	 */
281 	save_auth = clnt->cl_auth;
282 	clnt->cl_auth = auth;
283 
284 	/*
285 	 * set state for starting context setup
286 	 */
287 	input_token_p = GSS_C_NO_BUFFER;
288 
289 next_token:
290 	*gssstat = gss_init_sec_context(minor_stat,
291 					ap->my_cred,
292 					&ap->context,
293 					ap->target_name,
294 					ap->mech_type,
295 					ap->req_flags,
296 					ap->time_req,
297 					NULL,
298 					input_token_p,
299 					actual_mech_type,
300 					&call_arg,
301 					ret_flags,
302 					time_rec);
303 
304 	if (input_token_p != GSS_C_NO_BUFFER) {
305 		OM_uint32 minor_stat2;
306 
307 		(void) gss_release_buffer(&minor_stat2, input_token_p);
308 		input_token_p = GSS_C_NO_BUFFER;
309 	}
310 
311 	if (*gssstat != GSS_S_COMPLETE && *gssstat != GSS_S_CONTINUE_NEEDED) {
312 
313 		goto cleanup;
314 	}
315 
316 	/*
317 	 * if we got a token, pass it on
318 	 */
319 	if (call_arg.length != 0) {
320 		struct timeval timeout = {30, 0};
321 
322 		memset((char *)&call_res, 0, sizeof (call_res));
323 		callstat = clnt_call(clnt, NULLPROC,
324 				__xdr_rpc_gss_init_arg, (caddr_t)&call_arg,
325 				__xdr_rpc_gss_init_res, (caddr_t)&call_res,
326 				timeout);
327 		(void) gss_release_buffer(minor_stat, &call_arg);
328 
329 		if (callstat != RPC_SUCCESS) {
330 			goto cleanup;
331 		}
332 		/*
333 		 * we have results - note that these need to be freed
334 		 */
335 		free_results = TRUE;
336 
337 		if (call_res.gss_major != GSS_S_COMPLETE &&
338 			call_res.gss_major != GSS_S_CONTINUE_NEEDED)
339 			goto cleanup;
340 
341 		ap->gss_proc = RPCSEC_GSS_CONTINUE_INIT;
342 
343 		/*
344 		 * check for ctx_handle
345 		 */
346 		if (ap->ctx_handle.length == 0) {
347 			if (call_res.ctx_handle.length == 0)
348 				goto cleanup;
349 			GSS_DUP_BUFFER(ap->ctx_handle,
350 				call_res.ctx_handle);
351 		} else if (!GSS_BUFFERS_EQUAL(ap->ctx_handle,
352 						call_res.ctx_handle))
353 			goto cleanup;
354 
355 		/*
356 		 * check for token
357 		 */
358 		if (call_res.token.length != 0) {
359 			if (*gssstat == GSS_S_COMPLETE)
360 				goto cleanup;
361 			GSS_DUP_BUFFER(input_token, call_res.token);
362 			input_token_p = &input_token;
363 
364 		} else if (*gssstat != GSS_S_COMPLETE)
365 			goto cleanup;
366 
367 		/* save the sequence window value; validate later */
368 		ap->seq_window = call_res.seq_window;
369 		xdr_free(__xdr_rpc_gss_init_res, (caddr_t)&call_res);
370 		free_results = FALSE;
371 	}
372 
373 	/*
374 	 * results were okay.. continue if necessary
375 	 */
376 	if (*gssstat == GSS_S_CONTINUE_NEEDED)
377 		goto next_token;
378 
379 	/*
380 	 * Validate the sequence window - RFC 2203 section 5.2.3.1
381 	 */
382 	if (!validate_seqwin(ap)) {
383 		goto cleanup;
384 	}
385 
386 	/*
387 	 * Done!  Security context creation is successful.
388 	 * Ready for exchanging data.
389 	 */
390 	ap->established = TRUE;
391 	ap->seq_num = 1;
392 	ap->gss_proc = RPCSEC_GSS_DATA;
393 	ap->invalid = FALSE;
394 
395 	clnt->cl_auth = save_auth;	/* restore cl_auth */
396 	return (TRUE);
397 
398 cleanup:
399 	if (ap->context != GSS_C_NO_CONTEXT)
400 		rpc_gss_destroy_pvt(auth);
401 	if (free_results)
402 		xdr_free(__xdr_rpc_gss_init_res, (caddr_t)&call_res);
403 	clnt->cl_auth = save_auth;	/* restore cl_auth */
404 
405 /*
406  *	if (rpc_createerr.cf_stat == 0)
407  *		rpc_createerr.cf_stat = RPC_AUTHERROR;
408  */
409 	if (rpc_createerr.cf_stat == 0) {
410 		rpc_gss_err.rpc_gss_error = RPC_GSS_ER_SYSTEMERROR;
411 		rpc_gss_err.system_error = RPC_AUTHERROR;
412 	}
413 
414 	return (FALSE);
415 }
416 
417 /*
418  * Set service defaults.
419  */
420 bool_t
421 __rpc_gss_set_defaults(auth, service, qop)
422 	AUTH			*auth;
423 	rpc_gss_service_t	service;
424 	char			*qop;
425 {
426 	/*LINTED*/
427 	rpc_gss_data		*ap = AUTH_PRIVATE(auth);
428 	char			*mech;
429 	OM_uint32		qop_num;
430 
431 	switch (service) {
432 	case rpc_gss_svc_integrity:
433 	case rpc_gss_svc_privacy:
434 	case rpc_gss_svc_none:
435 		break;
436 	case rpc_gss_svc_default:
437 		service = rpc_gss_svc_integrity;
438 		break;
439 	default:
440 		return (FALSE);
441 	}
442 
443 	if ((mech = __rpc_gss_oid_to_mech(ap->mech_type)) == NULL)
444 		return (FALSE);
445 
446 	if (!__rpc_gss_qop_to_num(qop, mech, &qop_num))
447 		return (FALSE);
448 
449 	ap->qop = qop_num;
450 	ap->service = service;
451 	return (TRUE);
452 }
453 
454 /*
455  * Marshall credentials.
456  */
457 static bool_t
458 marshall_creds(ap, xdrs)
459 	rpc_gss_data		*ap;
460 	XDR			*xdrs;
461 {
462 	rpc_gss_creds		ag_creds;
463 	char			cred_buf[MAX_AUTH_BYTES];
464 	struct opaque_auth	creds;
465 	XDR			cred_xdrs;
466 
467 	ag_creds.version = ap->version;
468 	ag_creds.gss_proc = ap->gss_proc;
469 	ag_creds.seq_num = ap->seq_num;
470 	ag_creds.service = ap->service;
471 
472 	/*
473 	 * If context has not been set up yet, use NULL handle.
474 	 */
475 	if (ap->ctx_handle.length > 0)
476 		ag_creds.ctx_handle = ap->ctx_handle;
477 	else {
478 		ag_creds.ctx_handle.length = 0;
479 		ag_creds.ctx_handle.value = NULL;
480 	}
481 
482 	xdrmem_create(&cred_xdrs, (caddr_t)cred_buf, MAX_AUTH_BYTES,
483 								XDR_ENCODE);
484 	if (!__xdr_rpc_gss_creds(&cred_xdrs, &ag_creds)) {
485 		XDR_DESTROY(&cred_xdrs);
486 		return (FALSE);
487 	}
488 
489 	creds.oa_flavor = RPCSEC_GSS;
490 	creds.oa_base = cred_buf;
491 	creds.oa_length = xdr_getpos(&cred_xdrs);
492 	XDR_DESTROY(&cred_xdrs);
493 
494 	if (!xdr_opaque_auth(xdrs, &creds))
495 		return (FALSE);
496 
497 	return (TRUE);
498 }
499 
500 /*
501  * Marshall verifier.  The verifier is the checksum of the RPC header
502  * up to and including the credential field.  The XDR handle that's
503  * passed in has the header up to and including the credential field
504  * encoded.  A pointer to the transmit buffer is also passed in.
505  */
506 static bool_t
507 marshall_verf(ap, xdrs, buf)
508 	rpc_gss_data		*ap;
509 	XDR			*xdrs;	/* send XDR */
510 	char			*buf;	/* pointer of send buffer */
511 {
512 	struct opaque_auth	verf;
513 	OM_uint32		major, minor;
514 	gss_buffer_desc		in_buf, out_buf;
515 	bool_t			ret = FALSE;
516 
517 	/*
518 	 * If context is not established yet, use NULL verifier.
519 	 */
520 	if (!ap->established) {
521 		verf.oa_flavor = AUTH_NONE;
522 		verf.oa_base = NULL;
523 		verf.oa_length = 0;
524 		return (xdr_opaque_auth(xdrs, &verf));
525 	}
526 
527 	verf.oa_flavor = RPCSEC_GSS;
528 	in_buf.length = xdr_getpos(xdrs);
529 	in_buf.value = buf;
530 	if ((major = gss_sign(&minor, ap->context, ap->qop, &in_buf,
531 					&out_buf)) != GSS_S_COMPLETE) {
532 		if (major == GSS_S_CONTEXT_EXPIRED) {
533 			ap->invalid = TRUE;
534 		}
535 		return (FALSE);
536 	}
537 	verf.oa_base = out_buf.value;
538 	verf.oa_length = out_buf.length;
539 	ret = xdr_opaque_auth(xdrs, &verf);
540 	(void) gss_release_buffer(&minor, &out_buf);
541 
542 	return (ret);
543 }
544 
545 /*
546  * Function: rpc_gss_nextverf.  Not used.
547  */
548 static void
549 rpc_gss_nextverf()
550 {
551 }
552 
553 /*
554  * Function: rpc_gss_marshall - not used.
555  */
556 static bool_t
557 rpc_gss_marshall(auth, xdrs)
558 	AUTH		*auth;
559 	XDR		*xdrs;
560 {
561 	if (!xdr_opaque_auth(xdrs, &auth->ah_cred) ||
562 				!xdr_opaque_auth(xdrs, &auth->ah_verf))
563 		return (FALSE);
564 	return (TRUE);
565 }
566 
567 /*
568  * Validate sequence window upon a successful RPCSEC_GSS INIT session.
569  * The sequence window sent back by the server should be verifiable by
570  * the verifier which is a checksum of the sequence window.
571  */
572 static bool_t
573 validate_seqwin(rpc_gss_data *ap)
574 {
575 	uint_t			seq_win_net;
576 	OM_uint32		major = 0, minor = 0;
577 	gss_buffer_desc		msg_buf, tok_buf;
578 	int			qop_state = 0;
579 
580 	seq_win_net = (uint_t)htonl(ap->seq_window);
581 	msg_buf.length = sizeof (seq_win_net);
582 	msg_buf.value = (char *)&seq_win_net;
583 	tok_buf.length = ap->verifier->oa_length;
584 	tok_buf.value = ap->verifier->oa_base;
585 	major = gss_verify(&minor, ap->context, &msg_buf, &tok_buf, &qop_state);
586 	if (major != GSS_S_COMPLETE)
587 	    return (FALSE);
588 	return (TRUE);
589 }
590 
591 /*
592  * Validate RPC response verifier from server.  The response verifier
593  * is the checksum of the request sequence number.
594  */
595 static bool_t
596 rpc_gss_validate(auth, verf)
597 	AUTH			*auth;
598 	struct opaque_auth	*verf;
599 {
600 	/*LINTED*/
601 	rpc_gss_data		*ap = AUTH_PRIVATE(auth);
602 	uint_t			seq_num_net;
603 	OM_uint32		major, minor;
604 	gss_buffer_desc		msg_buf, tok_buf;
605 	int			qop_state;
606 
607 	/*
608 	 * If context is not established yet, save the verifier for
609 	 * validating the sequence window later at the end of context
610 	 * creation session.
611 	 */
612 	if (!ap->established) {
613 	    if (ap->verifier == NULL) {
614 		ap->verifier = malloc(sizeof (struct opaque_auth));
615 		memset(ap->verifier, 0, sizeof (struct opaque_auth));
616 		if (verf->oa_length > 0)
617 		    ap->verifier->oa_base = malloc(verf->oa_length);
618 	    } else {
619 		if (ap->verifier->oa_length > 0)
620 		    free(ap->verifier->oa_base);
621 		if (verf->oa_length > 0)
622 		    ap->verifier->oa_base = malloc(verf->oa_length);
623 	    }
624 	    ap->verifier->oa_length = verf->oa_length;
625 	    bcopy(verf->oa_base, ap->verifier->oa_base, verf->oa_length);
626 	    return (TRUE);
627 	}
628 
629 	seq_num_net = (uint_t)htonl(ap->seq_num);
630 	msg_buf.length = sizeof (seq_num_net);
631 	msg_buf.value = (char *)&seq_num_net;
632 	tok_buf.length = verf->oa_length;
633 	tok_buf.value = verf->oa_base;
634 	major = gss_verify(&minor, ap->context, &msg_buf, &tok_buf, &qop_state);
635 	if (major != GSS_S_COMPLETE)
636 		return (FALSE);
637 	return (TRUE);
638 }
639 
640 /*
641  * Refresh client context.  This is necessary sometimes because the
642  * server will ocassionally destroy contexts based on LRU method, or
643  * because of expired credentials.
644  */
645 static bool_t
646 rpc_gss_refresh(auth, msg)
647 	AUTH		*auth;
648 	struct rpc_msg	*msg;
649 {
650 	/*LINTED*/
651 	rpc_gss_data	*ap = AUTH_PRIVATE(auth);
652 	OM_uint32	gssstat, minor_stat;
653 
654 	/*
655 	 * The context needs to be recreated only when the error status
656 	 * returned from the server is one of the following:
657 	 *	RPCSEC_GSS_NOCRED and RPCSEC_GSS_FAILED
658 	 * The existing context should not be destroyed unless the above
659 	 * error status codes are received or if the context has not
660 	 * been set up.
661 	 */
662 
663 	if (msg->rjcted_rply.rj_why == RPCSEC_GSS_NOCRED ||
664 			msg->rjcted_rply.rj_why == RPCSEC_GSS_FAILED ||
665 							!ap->established) {
666 		/*
667 		 * Destroy the context if necessary.  Use the same memory
668 		 * for the new context since we've already passed a pointer
669 		 * to it to the user.
670 		 */
671 		if (ap->context != GSS_C_NO_CONTEXT) {
672 			(void) gss_delete_sec_context(&minor_stat, &ap->context,
673 								NULL);
674 			ap->context = GSS_C_NO_CONTEXT;
675 		}
676 		if (ap->ctx_handle.length != 0) {
677 			(void) gss_release_buffer(&minor_stat,
678 							&ap->ctx_handle);
679 			ap->ctx_handle.length = 0;
680 			ap->ctx_handle.value = NULL;
681 		}
682 
683 		/*
684 		 * If the context was not already established, don't try to
685 		 * recreate it.
686 		 */
687 		if (!ap->established) {
688 			ap->invalid = TRUE;
689 			return (FALSE);
690 		}
691 
692 		/*
693 		 * Recreate context.
694 		 */
695 		if (rpc_gss_seccreate_pvt(&gssstat, &minor_stat, auth, ap,
696 		    (gss_OID *)0, (OM_uint32 *)0, (OM_uint32 *)0))
697 			return (TRUE);
698 		else {
699 			ap->invalid = TRUE;
700 			return (FALSE);
701 		}
702 	}
703 	return (FALSE);
704 }
705 
706 /*
707  * Destroy a context.
708  */
709 static void
710 rpc_gss_destroy(auth)
711 	AUTH		*auth;
712 {
713 	/*LINTED*/
714 	rpc_gss_data	*ap = AUTH_PRIVATE(auth);
715 
716 	rpc_gss_destroy_pvt(auth);
717 	free((char *)ap);
718 	free(auth);
719 }
720 
721 /*
722  * Private interface to destroy a context without freeing up
723  * the memory used by it.  We need to do this when a refresh
724  * fails, for example, so the user will still have a handle.
725  */
726 static void
727 rpc_gss_destroy_pvt(auth)
728 	AUTH		*auth;
729 {
730 	struct timeval	timeout;
731 	OM_uint32	minor_stat;
732 	/*LINTED*/
733 	rpc_gss_data	*ap = AUTH_PRIVATE(auth);
734 
735 	/*
736 	 * If we have a server context id, inform server that we are
737 	 * destroying the context.
738 	 */
739 	if (ap->ctx_handle.length != 0) {
740 		ap->gss_proc = RPCSEC_GSS_DESTROY;
741 		timeout.tv_sec = 1;
742 		timeout.tv_usec = 0;
743 		(void) clnt_call(ap->clnt, NULLPROC, xdr_void, NULL,
744 						xdr_void, NULL, timeout);
745 
746 		(void) gss_release_buffer(&minor_stat, &ap->ctx_handle);
747 		ap->ctx_handle.length = 0;
748 		ap->ctx_handle.value = NULL;
749 	}
750 
751 	/*
752 	 * Destroy local GSS context.
753 	 */
754 	if (ap->context != GSS_C_NO_CONTEXT) {
755 		(void) gss_delete_sec_context(&minor_stat, &ap->context, NULL);
756 		ap->context = GSS_C_NO_CONTEXT;
757 	}
758 
759 	/*
760 	 * Looks like we need to release default credentials if we use it.
761 	 * Non-default creds need to be released by user.
762 	 */
763 	if (ap->my_cred == GSS_C_NO_CREDENTIAL)
764 		(void) gss_release_cred(&minor_stat, &ap->my_cred);
765 
766 	/*
767 	 * Release any internal name structures.
768 	 */
769 	if (ap->target_name != NULL) {
770 		(void) gss_release_name(&minor_stat, &ap->target_name);
771 		ap->target_name = NULL;
772 	}
773 
774 	/*
775 	 * Free the verifier saved for sequence window checking.
776 	 */
777 	if (ap->verifier != NULL) {
778 	    if (ap->verifier->oa_length > 0)
779 		free(ap->verifier->oa_base);
780 	    free(ap->verifier);
781 	    ap->verifier = NULL;
782 	}
783 }
784 
785 /*
786  * Wrap client side data.  The encoded header is passed in through
787  * buf and buflen.  The header is up to but not including the
788  * credential field.
789  */
790 bool_t
791 __rpc_gss_wrap(auth, buf, buflen, out_xdrs, xdr_func, xdr_ptr)
792 	AUTH			*auth;
793 	char			*buf;		/* encoded header */
794 	uint_t			buflen;		/* encoded header length */
795 	XDR			*out_xdrs;
796 	bool_t			(*xdr_func)();
797 	caddr_t			xdr_ptr;
798 {
799 	/*LINTED*/
800 	rpc_gss_data		*ap = AUTH_PRIVATE(auth);
801 	XDR			xdrs;
802 	char			tmp_buf[512];
803 
804 
805 	/*
806 	 * Reject an invalid context.
807 	 */
808 	if (ap->invalid)
809 		return (FALSE);
810 
811 	/*
812 	 * If context is established, bump up sequence number.
813 	 */
814 	if (ap->established)
815 		ap->seq_num++;
816 
817 	/*
818 	 * Create the header in a temporary XDR context and buffer
819 	 * before putting it out.
820 	 */
821 	xdrmem_create(&xdrs, tmp_buf, sizeof (tmp_buf), XDR_ENCODE);
822 	if (!XDR_PUTBYTES(&xdrs, buf, buflen))
823 		return (FALSE);
824 
825 	/*
826 	 * create cred field
827 	 */
828 	if (!marshall_creds(ap, &xdrs))
829 		return (FALSE);
830 
831 	/*
832 	 * create verifier
833 	 */
834 	if (!marshall_verf(ap, &xdrs, tmp_buf))
835 		return (FALSE);
836 
837 	/*
838 	 * write out header and destroy temp structures
839 	 */
840 	if (!XDR_PUTBYTES(out_xdrs, tmp_buf, XDR_GETPOS(&xdrs)))
841 		return (FALSE);
842 	XDR_DESTROY(&xdrs);
843 
844 	/*
845 	 * If context is not established, or if neither integrity
846 	 * nor privacy is used, just XDR encode data.
847 	 */
848 	if (!ap->established || ap->service == rpc_gss_svc_none)
849 		return ((*xdr_func)(out_xdrs, xdr_ptr));
850 
851 	return (__rpc_gss_wrap_data(ap->service, ap->qop, ap->context,
852 				ap->seq_num, out_xdrs, xdr_func, xdr_ptr));
853 }
854 
855 /*
856  * Unwrap received data.
857  */
858 bool_t
859 __rpc_gss_unwrap(auth, in_xdrs, xdr_func, xdr_ptr)
860 	AUTH			*auth;
861 	XDR			*in_xdrs;
862 	bool_t			(*xdr_func)();
863 	caddr_t			xdr_ptr;
864 {
865 	/*LINTED*/
866 	rpc_gss_data		*ap = AUTH_PRIVATE(auth);
867 
868 	/*
869 	 * If context is not established, of if neither integrity
870 	 * nor privacy is used, just XDR encode data.
871 	 */
872 	if (!ap->established || ap->service == rpc_gss_svc_none)
873 		return ((*xdr_func)(in_xdrs, xdr_ptr));
874 
875 	return (__rpc_gss_unwrap_data(ap->service,
876 				ap->context,
877 				ap->seq_num,
878 				ap->qop,
879 				in_xdrs, xdr_func, xdr_ptr));
880 }
881 
882 int
883 __rpc_gss_max_data_length(auth, max_tp_unit_len)
884 	AUTH		*auth;
885 	int		max_tp_unit_len;
886 {
887 	/*LINTED*/
888 	rpc_gss_data		*ap = AUTH_PRIVATE(auth);
889 
890 	if (!ap->established || max_tp_unit_len <= 0)
891 		return (0);
892 
893 	return (__find_max_data_length(ap->service,
894 			ap->context,
895 			ap->qop,
896 			max_tp_unit_len));
897 }
898 
899 void
900 __rpc_gss_get_error(rpc_gss_error_t *error)
901 {
902 	*error = rpc_gss_err;
903 }
904 
905 #undef  rpc_gss_err
906 
907 rpc_gss_error_t	rpc_gss_err;
908 
909 rpc_gss_error_t *
910 __rpc_gss_err()
911 {
912 	static thread_key_t rpc_gss_err_key = THR_ONCE_KEY;
913 	rpc_gss_error_t *tsd;
914 
915 	if (_thr_main())
916 		return (&rpc_gss_err);
917 	if (_thr_keycreate_once(&rpc_gss_err_key, free) != 0)
918 		return (&rpc_gss_err);
919 	tsd = _pthread_getspecific(rpc_gss_err_key);
920 	if (tsd == NULL) {
921 		tsd = (rpc_gss_error_t *)calloc(1, sizeof (rpc_gss_error_t));
922 		if (_thr_setspecific(rpc_gss_err_key, tsd) != 0) {
923 			if (tsd)
924 				free(tsd);
925 			return (&rpc_gss_err);
926 		}
927 	}
928 	return (tsd);
929 }
930