xref: /freebsd/usr.sbin/gssd/gssd.c (revision 646a7fea0c8a60ce2795ffc1bdf58e0fd0f7d624)
1 /*-
2  * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
3  * Authors: Doug Rabson <dfr@rabson.org>
4  * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
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  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  */
27 
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30 
31 #include <sys/param.h>
32 #include <sys/stat.h>
33 #include <sys/linker.h>
34 #include <sys/module.h>
35 #include <sys/queue.h>
36 #include <sys/syslog.h>
37 #include <ctype.h>
38 #include <dirent.h>
39 #include <err.h>
40 #ifndef WITHOUT_KERBEROS
41 #include <krb5.h>
42 #endif
43 #include <pwd.h>
44 #include <stdio.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 #include <gssapi/gssapi.h>
49 #include <rpc/rpc.h>
50 #include <rpc/rpc_com.h>
51 
52 #include "gssd.h"
53 
54 #ifndef _PATH_GSS_MECH
55 #define _PATH_GSS_MECH	"/etc/gss/mech"
56 #endif
57 #ifndef _PATH_GSSDSOCK
58 #define _PATH_GSSDSOCK	"/var/run/gssd.sock"
59 #endif
60 
61 struct gss_resource {
62 	LIST_ENTRY(gss_resource) gr_link;
63 	uint64_t	gr_id;	/* indentifier exported to kernel */
64 	void*		gr_res;	/* GSS-API resource pointer */
65 };
66 LIST_HEAD(gss_resource_list, gss_resource) gss_resources;
67 int gss_resource_count;
68 uint32_t gss_next_id;
69 uint32_t gss_start_time;
70 int debug_level;
71 static char ccfile_dirlist[PATH_MAX + 1], ccfile_substring[NAME_MAX + 1];
72 static char pref_realm[1024];
73 
74 static void gssd_load_mech(void);
75 static int find_ccache_file(const char *, uid_t, char *);
76 static int is_a_valid_tgt_cache(const char *, uid_t, int *, time_t *);
77 
78 extern void gssd_1(struct svc_req *rqstp, SVCXPRT *transp);
79 extern int gssd_syscall(char *path);
80 
81 int
82 main(int argc, char **argv)
83 {
84 	/*
85 	 * We provide an RPC service on a local-domain socket. The
86 	 * kernel's GSS-API code will pass what it can't handle
87 	 * directly to us.
88 	 */
89 	struct sockaddr_un sun;
90 	int fd, oldmask, ch, debug;
91 	SVCXPRT *xprt;
92 
93 	/*
94 	 * Initialize the credential cache file name substring and the
95 	 * search directory list.
96 	 */
97 	strlcpy(ccfile_substring, "krb5cc_", sizeof(ccfile_substring));
98 	ccfile_dirlist[0] = '\0';
99 	pref_realm[0] = '\0';
100 	debug = 0;
101 	while ((ch = getopt(argc, argv, "ds:c:r:")) != -1) {
102 		switch (ch) {
103 		case 'd':
104 			debug_level++;
105 			break;
106 		case 's':
107 #ifndef WITHOUT_KERBEROS
108 			/*
109 			 * Set the directory search list. This enables use of
110 			 * find_ccache_file() to search the directories for a
111 			 * suitable credentials cache file.
112 			 */
113 			strlcpy(ccfile_dirlist, optarg, sizeof(ccfile_dirlist));
114 #else
115 			errx(1, "This option not available when built"
116 			    " without MK_KERBEROS\n");
117 #endif
118 			break;
119 		case 'c':
120 			/*
121 			 * Specify a non-default credential cache file
122 			 * substring.
123 			 */
124 			strlcpy(ccfile_substring, optarg,
125 			    sizeof(ccfile_substring));
126 			break;
127 		case 'r':
128 			/*
129 			 * Set the preferred realm for the credential cache tgt.
130 			 */
131 			strlcpy(pref_realm, optarg, sizeof(pref_realm));
132 			break;
133 		default:
134 			fprintf(stderr,
135 			    "usage: %s [-d] [-s dir-list] [-c file-substring]"
136 			    " [-r preferred-realm]\n", argv[0]);
137 			exit(1);
138 			break;
139 		}
140 	}
141 
142 	gssd_load_mech();
143 
144 	if (!debug_level)
145 		daemon(0, 0);
146 
147 	memset(&sun, 0, sizeof sun);
148 	sun.sun_family = AF_LOCAL;
149 	unlink(_PATH_GSSDSOCK);
150 	strcpy(sun.sun_path, _PATH_GSSDSOCK);
151 	sun.sun_len = SUN_LEN(&sun);
152 	fd = socket(AF_LOCAL, SOCK_STREAM, 0);
153 	if (!fd) {
154 		if (debug_level == 0) {
155 			syslog(LOG_ERR, "Can't create local gssd socket");
156 			exit(1);
157 		}
158 		err(1, "Can't create local gssd socket");
159 	}
160 	oldmask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
161 	if (bind(fd, (struct sockaddr *) &sun, sun.sun_len) < 0) {
162 		if (debug_level == 0) {
163 			syslog(LOG_ERR, "Can't bind local gssd socket");
164 			exit(1);
165 		}
166 		err(1, "Can't bind local gssd socket");
167 	}
168 	umask(oldmask);
169 	if (listen(fd, SOMAXCONN) < 0) {
170 		if (debug_level == 0) {
171 			syslog(LOG_ERR, "Can't listen on local gssd socket");
172 			exit(1);
173 		}
174 		err(1, "Can't listen on local gssd socket");
175 	}
176 	xprt = svc_vc_create(fd, RPC_MAXDATASIZE, RPC_MAXDATASIZE);
177 	if (!xprt) {
178 		if (debug_level == 0) {
179 			syslog(LOG_ERR,
180 			    "Can't create transport for local gssd socket");
181 			exit(1);
182 		}
183 		err(1, "Can't create transport for local gssd socket");
184 	}
185 	if (!svc_reg(xprt, GSSD, GSSDVERS, gssd_1, NULL)) {
186 		if (debug_level == 0) {
187 			syslog(LOG_ERR,
188 			    "Can't register service for local gssd socket");
189 			exit(1);
190 		}
191 		err(1, "Can't register service for local gssd socket");
192 	}
193 
194 	LIST_INIT(&gss_resources);
195 	gss_next_id = 1;
196 	gss_start_time = time(0);
197 
198 	gssd_syscall(_PATH_GSSDSOCK);
199 	svc_run();
200 
201 	return (0);
202 }
203 
204 static void
205 gssd_load_mech(void)
206 {
207 	FILE		*fp;
208 	char		buf[256];
209 	char		*p;
210 	char		*name, *oid, *lib, *kobj;
211 
212 	fp = fopen(_PATH_GSS_MECH, "r");
213 	if (!fp)
214 		return;
215 
216 	while (fgets(buf, sizeof(buf), fp)) {
217 		if (*buf == '#')
218 			continue;
219 		p = buf;
220 		name = strsep(&p, "\t\n ");
221 		if (p) while (isspace(*p)) p++;
222 		oid = strsep(&p, "\t\n ");
223 		if (p) while (isspace(*p)) p++;
224 		lib = strsep(&p, "\t\n ");
225 		if (p) while (isspace(*p)) p++;
226 		kobj = strsep(&p, "\t\n ");
227 		if (!name || !oid || !lib || !kobj)
228 			continue;
229 
230 		if (strcmp(kobj, "-")) {
231 			/*
232 			 * Attempt to load the kernel module if its
233 			 * not already present.
234 			 */
235 			if (modfind(kobj) < 0) {
236 				if (kldload(kobj) < 0) {
237 					fprintf(stderr,
238 			"%s: can't find or load kernel module %s for %s\n",
239 					    getprogname(), kobj, name);
240 				}
241 			}
242 		}
243 	}
244 	fclose(fp);
245 }
246 
247 static void *
248 gssd_find_resource(uint64_t id)
249 {
250 	struct gss_resource *gr;
251 
252 	if (!id)
253 		return (NULL);
254 
255 	LIST_FOREACH(gr, &gss_resources, gr_link)
256 		if (gr->gr_id == id)
257 			return (gr->gr_res);
258 
259 	return (NULL);
260 }
261 
262 static uint64_t
263 gssd_make_resource(void *res)
264 {
265 	struct gss_resource *gr;
266 
267 	if (!res)
268 		return (0);
269 
270 	gr = malloc(sizeof(struct gss_resource));
271 	if (!gr)
272 		return (0);
273 	gr->gr_id = (gss_next_id++) + ((uint64_t) gss_start_time << 32);
274 	gr->gr_res = res;
275 	LIST_INSERT_HEAD(&gss_resources, gr, gr_link);
276 	gss_resource_count++;
277 	if (debug_level > 1)
278 		printf("%d resources allocated\n", gss_resource_count);
279 
280 	return (gr->gr_id);
281 }
282 
283 static void
284 gssd_delete_resource(uint64_t id)
285 {
286 	struct gss_resource *gr;
287 
288 	LIST_FOREACH(gr, &gss_resources, gr_link) {
289 		if (gr->gr_id == id) {
290 			LIST_REMOVE(gr, gr_link);
291 			free(gr);
292 			gss_resource_count--;
293 			if (debug_level > 1)
294 				printf("%d resources allocated\n",
295 				    gss_resource_count);
296 			return;
297 		}
298 	}
299 }
300 
301 bool_t
302 gssd_null_1_svc(void *argp, void *result, struct svc_req *rqstp)
303 {
304 
305 	return (TRUE);
306 }
307 
308 bool_t
309 gssd_init_sec_context_1_svc(init_sec_context_args *argp, init_sec_context_res *result, struct svc_req *rqstp)
310 {
311 	gss_cred_id_t cred = GSS_C_NO_CREDENTIAL;
312 	gss_ctx_id_t ctx = GSS_C_NO_CONTEXT;
313 	gss_name_t name = GSS_C_NO_NAME;
314 	char ccname[PATH_MAX + 5 + 1], *cp, *cp2;
315 	int gotone;
316 
317 	memset(result, 0, sizeof(*result));
318 	if (ccfile_dirlist[0] != '\0' && argp->cred == 0) {
319 		/*
320 		 * For the "-s" case and no credentials provided as an
321 		 * argument, search the directory list for an appropriate
322 		 * credential cache file. If the search fails, return failure.
323 		 */
324 		gotone = 0;
325 		cp = ccfile_dirlist;
326 		do {
327 			cp2 = strchr(cp, ':');
328 			if (cp2 != NULL)
329 				*cp2 = '\0';
330 			gotone = find_ccache_file(cp, argp->uid, ccname);
331 			if (gotone != 0)
332 				break;
333 			if (cp2 != NULL)
334 				*cp2++ = ':';
335 			cp = cp2;
336 		} while (cp != NULL && *cp != '\0');
337 		if (gotone == 0) {
338 			result->major_status = GSS_S_CREDENTIALS_EXPIRED;
339 			return (TRUE);
340 		}
341 	} else {
342 		/*
343 		 * If there wasn't a "-s" option or the credentials have
344 		 * been provided as an argument, do it the old way.
345 		 * When credentials are provided, the uid should be root.
346 		 */
347 		if (argp->cred != 0 && argp->uid != 0) {
348 			if (debug_level == 0)
349 				syslog(LOG_ERR, "gss_init_sec_context:"
350 				    " cred for non-root");
351 			else
352 				fprintf(stderr, "gss_init_sec_context:"
353 				    " cred for non-root\n");
354 		}
355 		snprintf(ccname, sizeof(ccname), "FILE:/tmp/krb5cc_%d",
356 		    (int) argp->uid);
357 	}
358 	setenv("KRB5CCNAME", ccname, TRUE);
359 
360 	if (argp->cred) {
361 		cred = gssd_find_resource(argp->cred);
362 		if (!cred) {
363 			result->major_status = GSS_S_CREDENTIALS_EXPIRED;
364 			return (TRUE);
365 		}
366 	}
367 	if (argp->ctx) {
368 		ctx = gssd_find_resource(argp->ctx);
369 		if (!ctx) {
370 			result->major_status = GSS_S_CONTEXT_EXPIRED;
371 			return (TRUE);
372 		}
373 	}
374 	if (argp->name) {
375 		name = gssd_find_resource(argp->name);
376 		if (!name) {
377 			result->major_status = GSS_S_BAD_NAME;
378 			return (TRUE);
379 		}
380 	}
381 
382 	result->major_status = gss_init_sec_context(&result->minor_status,
383 	    cred, &ctx, name, argp->mech_type,
384 	    argp->req_flags, argp->time_req, argp->input_chan_bindings,
385 	    &argp->input_token, &result->actual_mech_type,
386 	    &result->output_token, &result->ret_flags, &result->time_rec);
387 
388 	if (result->major_status == GSS_S_COMPLETE
389 	    || result->major_status == GSS_S_CONTINUE_NEEDED) {
390 		if (argp->ctx)
391 			result->ctx = argp->ctx;
392 		else
393 			result->ctx = gssd_make_resource(ctx);
394 	}
395 
396 	return (TRUE);
397 }
398 
399 bool_t
400 gssd_accept_sec_context_1_svc(accept_sec_context_args *argp, accept_sec_context_res *result, struct svc_req *rqstp)
401 {
402 	gss_ctx_id_t ctx = GSS_C_NO_CONTEXT;
403 	gss_cred_id_t cred = GSS_C_NO_CREDENTIAL;
404 	gss_name_t src_name;
405 	gss_cred_id_t delegated_cred_handle;
406 
407 	memset(result, 0, sizeof(*result));
408 	if (argp->ctx) {
409 		ctx = gssd_find_resource(argp->ctx);
410 		if (!ctx) {
411 			result->major_status = GSS_S_CONTEXT_EXPIRED;
412 			return (TRUE);
413 		}
414 	}
415 	if (argp->cred) {
416 		cred = gssd_find_resource(argp->cred);
417 		if (!cred) {
418 			result->major_status = GSS_S_CREDENTIALS_EXPIRED;
419 			return (TRUE);
420 		}
421 	}
422 
423 	memset(result, 0, sizeof(*result));
424 	result->major_status = gss_accept_sec_context(&result->minor_status,
425 	    &ctx, cred, &argp->input_token, argp->input_chan_bindings,
426 	    &src_name, &result->mech_type, &result->output_token,
427 	    &result->ret_flags, &result->time_rec,
428 	    &delegated_cred_handle);
429 
430 	if (result->major_status == GSS_S_COMPLETE
431 	    || result->major_status == GSS_S_CONTINUE_NEEDED) {
432 		if (argp->ctx)
433 			result->ctx = argp->ctx;
434 		else
435 			result->ctx = gssd_make_resource(ctx);
436 		result->src_name = gssd_make_resource(src_name);
437 		result->delegated_cred_handle =
438 			gssd_make_resource(delegated_cred_handle);
439 	}
440 
441 	return (TRUE);
442 }
443 
444 bool_t
445 gssd_delete_sec_context_1_svc(delete_sec_context_args *argp, delete_sec_context_res *result, struct svc_req *rqstp)
446 {
447 	gss_ctx_id_t ctx = gssd_find_resource(argp->ctx);
448 
449 	if (ctx) {
450 		result->major_status = gss_delete_sec_context(
451 			&result->minor_status, &ctx, &result->output_token);
452 		gssd_delete_resource(argp->ctx);
453 	} else {
454 		result->major_status = GSS_S_COMPLETE;
455 		result->minor_status = 0;
456 	}
457 
458 	return (TRUE);
459 }
460 
461 bool_t
462 gssd_export_sec_context_1_svc(export_sec_context_args *argp, export_sec_context_res *result, struct svc_req *rqstp)
463 {
464 	gss_ctx_id_t ctx = gssd_find_resource(argp->ctx);
465 
466 	if (ctx) {
467 		result->major_status = gss_export_sec_context(
468 			&result->minor_status, &ctx,
469 			&result->interprocess_token);
470 		result->format = KGSS_HEIMDAL_1_1;
471 		gssd_delete_resource(argp->ctx);
472 	} else {
473 		result->major_status = GSS_S_FAILURE;
474 		result->minor_status = 0;
475 		result->interprocess_token.length = 0;
476 		result->interprocess_token.value = NULL;
477 	}
478 
479 	return (TRUE);
480 }
481 
482 bool_t
483 gssd_import_name_1_svc(import_name_args *argp, import_name_res *result, struct svc_req *rqstp)
484 {
485 	gss_name_t name;
486 
487 	result->major_status = gss_import_name(&result->minor_status,
488 	    &argp->input_name_buffer, argp->input_name_type, &name);
489 
490 	if (result->major_status == GSS_S_COMPLETE)
491 		result->output_name = gssd_make_resource(name);
492 	else
493 		result->output_name = 0;
494 
495 	return (TRUE);
496 }
497 
498 bool_t
499 gssd_canonicalize_name_1_svc(canonicalize_name_args *argp, canonicalize_name_res *result, struct svc_req *rqstp)
500 {
501 	gss_name_t name = gssd_find_resource(argp->input_name);
502 	gss_name_t output_name;
503 
504 	memset(result, 0, sizeof(*result));
505 	if (!name) {
506 		result->major_status = GSS_S_BAD_NAME;
507 		return (TRUE);
508 	}
509 
510 	result->major_status = gss_canonicalize_name(&result->minor_status,
511 	    name, argp->mech_type, &output_name);
512 
513 	if (result->major_status == GSS_S_COMPLETE)
514 		result->output_name = gssd_make_resource(output_name);
515 	else
516 		result->output_name = 0;
517 
518 	return (TRUE);
519 }
520 
521 bool_t
522 gssd_export_name_1_svc(export_name_args *argp, export_name_res *result, struct svc_req *rqstp)
523 {
524 	gss_name_t name = gssd_find_resource(argp->input_name);
525 
526 	memset(result, 0, sizeof(*result));
527 	if (!name) {
528 		result->major_status = GSS_S_BAD_NAME;
529 		return (TRUE);
530 	}
531 
532 	result->major_status = gss_export_name(&result->minor_status,
533 	    name, &result->exported_name);
534 
535 	return (TRUE);
536 }
537 
538 bool_t
539 gssd_release_name_1_svc(release_name_args *argp, release_name_res *result, struct svc_req *rqstp)
540 {
541 	gss_name_t name = gssd_find_resource(argp->input_name);
542 
543 	if (name) {
544 		result->major_status = gss_release_name(&result->minor_status,
545 		    &name);
546 		gssd_delete_resource(argp->input_name);
547 	} else {
548 		result->major_status = GSS_S_COMPLETE;
549 		result->minor_status = 0;
550 	}
551 
552 	return (TRUE);
553 }
554 
555 bool_t
556 gssd_pname_to_uid_1_svc(pname_to_uid_args *argp, pname_to_uid_res *result, struct svc_req *rqstp)
557 {
558 	gss_name_t name = gssd_find_resource(argp->pname);
559 	uid_t uid;
560 	char buf[128];
561 	struct passwd pwd, *pw;
562 
563 	memset(result, 0, sizeof(*result));
564 	if (name) {
565 		result->major_status =
566 			gss_pname_to_uid(&result->minor_status,
567 			    name, argp->mech, &uid);
568 		if (result->major_status == GSS_S_COMPLETE) {
569 			result->uid = uid;
570 			getpwuid_r(uid, &pwd, buf, sizeof(buf), &pw);
571 			if (pw) {
572 				int len = NGRPS;
573 				int groups[NGRPS];
574 				result->gid = pw->pw_gid;
575 				getgrouplist(pw->pw_name, pw->pw_gid,
576 				    groups, &len);
577 				result->gidlist.gidlist_len = len;
578 				result->gidlist.gidlist_val =
579 					mem_alloc(len * sizeof(int));
580 				memcpy(result->gidlist.gidlist_val, groups,
581 				    len * sizeof(int));
582 			} else {
583 				result->gid = 65534;
584 				result->gidlist.gidlist_len = 0;
585 				result->gidlist.gidlist_val = NULL;
586 			}
587 		}
588 	} else {
589 		result->major_status = GSS_S_BAD_NAME;
590 		result->minor_status = 0;
591 	}
592 
593 	return (TRUE);
594 }
595 
596 bool_t
597 gssd_acquire_cred_1_svc(acquire_cred_args *argp, acquire_cred_res *result, struct svc_req *rqstp)
598 {
599 	gss_name_t desired_name = GSS_C_NO_NAME;
600 	gss_cred_id_t cred;
601 	char ccname[PATH_MAX + 5 + 1], *cp, *cp2;
602 	int gotone;
603 
604 	memset(result, 0, sizeof(*result));
605 	if (ccfile_dirlist[0] != '\0' && argp->desired_name == 0) {
606 		/*
607 		 * For the "-s" case and no name provided as an
608 		 * argument, search the directory list for an appropriate
609 		 * credential cache file. If the search fails, return failure.
610 		 */
611 		gotone = 0;
612 		cp = ccfile_dirlist;
613 		do {
614 			cp2 = strchr(cp, ':');
615 			if (cp2 != NULL)
616 				*cp2 = '\0';
617 			gotone = find_ccache_file(cp, argp->uid, ccname);
618 			if (gotone != 0)
619 				break;
620 			if (cp2 != NULL)
621 				*cp2++ = ':';
622 			cp = cp2;
623 		} while (cp != NULL && *cp != '\0');
624 		if (gotone == 0) {
625 			result->major_status = GSS_S_CREDENTIALS_EXPIRED;
626 			return (TRUE);
627 		}
628 	} else {
629 		/*
630 		 * If there wasn't a "-s" option or the name has
631 		 * been provided as an argument, do it the old way.
632 		 * When a name is provided, it will normally exist in the
633 		 * default keytab file and the uid will be root.
634 		 */
635 		if (argp->desired_name != 0 && argp->uid != 0) {
636 			if (debug_level == 0)
637 				syslog(LOG_ERR, "gss_acquire_cred:"
638 				    " principal_name for non-root");
639 			else
640 				fprintf(stderr, "gss_acquire_cred:"
641 				    " principal_name for non-root\n");
642 		}
643 		snprintf(ccname, sizeof(ccname), "FILE:/tmp/krb5cc_%d",
644 		    (int) argp->uid);
645 	}
646 	setenv("KRB5CCNAME", ccname, TRUE);
647 
648 	if (argp->desired_name) {
649 		desired_name = gssd_find_resource(argp->desired_name);
650 		if (!desired_name) {
651 			result->major_status = GSS_S_BAD_NAME;
652 			return (TRUE);
653 		}
654 	}
655 
656 	result->major_status = gss_acquire_cred(&result->minor_status,
657 	    desired_name, argp->time_req, argp->desired_mechs,
658 	    argp->cred_usage, &cred, &result->actual_mechs, &result->time_rec);
659 
660 	if (result->major_status == GSS_S_COMPLETE)
661 		result->output_cred = gssd_make_resource(cred);
662 	else
663 		result->output_cred = 0;
664 
665 	return (TRUE);
666 }
667 
668 bool_t
669 gssd_set_cred_option_1_svc(set_cred_option_args *argp, set_cred_option_res *result, struct svc_req *rqstp)
670 {
671 	gss_cred_id_t cred = gssd_find_resource(argp->cred);
672 
673 	memset(result, 0, sizeof(*result));
674 	if (!cred) {
675 		result->major_status = GSS_S_CREDENTIALS_EXPIRED;
676 		return (TRUE);
677 	}
678 
679 	result->major_status = gss_set_cred_option(&result->minor_status,
680 	    &cred, argp->option_name, &argp->option_value);
681 
682 	return (TRUE);
683 }
684 
685 bool_t
686 gssd_release_cred_1_svc(release_cred_args *argp, release_cred_res *result, struct svc_req *rqstp)
687 {
688 	gss_cred_id_t cred = gssd_find_resource(argp->cred);
689 
690 	if (cred) {
691 		result->major_status = gss_release_cred(&result->minor_status,
692 		    &cred);
693 		gssd_delete_resource(argp->cred);
694 	} else {
695 		result->major_status = GSS_S_COMPLETE;
696 		result->minor_status = 0;
697 	}
698 
699 	return (TRUE);
700 }
701 
702 bool_t
703 gssd_display_status_1_svc(display_status_args *argp, display_status_res *result, struct svc_req *rqstp)
704 {
705 
706 	result->message_context = argp->message_context;
707 	result->major_status = gss_display_status(&result->minor_status,
708 	    argp->status_value, argp->status_type, argp->mech_type,
709 	    &result->message_context, &result->status_string);
710 
711 	return (TRUE);
712 }
713 
714 int
715 gssd_1_freeresult(SVCXPRT *transp, xdrproc_t xdr_result, caddr_t result)
716 {
717 	/*
718 	 * We don't use XDR to free the results - anything which was
719 	 * allocated came from GSS-API. We use xdr_result to figure
720 	 * out what to do.
721 	 */
722 	OM_uint32 junk;
723 
724 	if (xdr_result == (xdrproc_t) xdr_init_sec_context_res) {
725 		init_sec_context_res *p = (init_sec_context_res *) result;
726 		gss_release_buffer(&junk, &p->output_token);
727 	} else if (xdr_result == (xdrproc_t) xdr_accept_sec_context_res) {
728 		accept_sec_context_res *p = (accept_sec_context_res *) result;
729 		gss_release_buffer(&junk, &p->output_token);
730 	} else if (xdr_result == (xdrproc_t) xdr_delete_sec_context_res) {
731 		delete_sec_context_res *p = (delete_sec_context_res *) result;
732 		gss_release_buffer(&junk, &p->output_token);
733 	} else if (xdr_result == (xdrproc_t) xdr_export_sec_context_res) {
734 		export_sec_context_res *p = (export_sec_context_res *) result;
735 		if (p->interprocess_token.length)
736 			memset(p->interprocess_token.value, 0,
737 			    p->interprocess_token.length);
738 		gss_release_buffer(&junk, &p->interprocess_token);
739 	} else if (xdr_result == (xdrproc_t) xdr_export_name_res) {
740 		export_name_res *p = (export_name_res *) result;
741 		gss_release_buffer(&junk, &p->exported_name);
742 	} else if (xdr_result == (xdrproc_t) xdr_acquire_cred_res) {
743 		acquire_cred_res *p = (acquire_cred_res *) result;
744 		gss_release_oid_set(&junk, &p->actual_mechs);
745 	} else if (xdr_result == (xdrproc_t) xdr_pname_to_uid_res) {
746 		pname_to_uid_res *p = (pname_to_uid_res *) result;
747 		if (p->gidlist.gidlist_val)
748 			free(p->gidlist.gidlist_val);
749 	} else if (xdr_result == (xdrproc_t) xdr_display_status_res) {
750 		display_status_res *p = (display_status_res *) result;
751 		gss_release_buffer(&junk, &p->status_string);
752 	}
753 
754 	return (TRUE);
755 }
756 
757 /*
758  * Search a directory for the most likely candidate to be used as the
759  * credential cache for a uid. If successful, return 1 and fill the
760  * file's path id into "rpath". Otherwise, return 0.
761  */
762 static int
763 find_ccache_file(const char *dirpath, uid_t uid, char *rpath)
764 {
765 	DIR *dirp;
766 	struct dirent *dp;
767 	struct stat sb;
768 	time_t exptime, oexptime;
769 	int gotone, len, rating, orating;
770 	char namepath[PATH_MAX + 5 + 1];
771 	char retpath[PATH_MAX + 5 + 1];
772 
773 	dirp = opendir(dirpath);
774 	if (dirp == NULL)
775 		return (0);
776 	gotone = 0;
777 	orating = 0;
778 	oexptime = 0;
779 	while ((dp = readdir(dirp)) != NULL) {
780 		len = snprintf(namepath, sizeof(namepath), "%s/%s", dirpath,
781 		    dp->d_name);
782 		if (len < sizeof(namepath) &&
783 		    strstr(dp->d_name, ccfile_substring) != NULL &&
784 		    lstat(namepath, &sb) >= 0 &&
785 		    sb.st_uid == uid &&
786 		    S_ISREG(sb.st_mode)) {
787 			len = snprintf(namepath, sizeof(namepath), "FILE:%s/%s",
788 			    dirpath, dp->d_name);
789 			if (len < sizeof(namepath) &&
790 			    is_a_valid_tgt_cache(namepath, uid, &rating,
791 			    &exptime) != 0) {
792 				if (gotone == 0 || rating > orating ||
793 				    (rating == orating && exptime > oexptime)) {
794 					orating = rating;
795 					oexptime = exptime;
796 					strcpy(retpath, namepath);
797 					gotone = 1;
798 				}
799 			}
800 		}
801 	}
802 	closedir(dirp);
803 	if (gotone != 0) {
804 		strcpy(rpath, retpath);
805 		return (1);
806 	}
807 	return (0);
808 }
809 
810 /*
811  * Try to determine if the file is a valid tgt cache file.
812  * Check that the file has a valid tgt for a principal.
813  * If it does, return 1, otherwise return 0.
814  * It also returns a "rating" and the expiry time for the TGT, when found.
815  * This "rating" is higher based on heuristics that make it more
816  * likely to be the correct credential cache file to use. It can
817  * be used by the caller, along with expiry time, to select from
818  * multiple credential cache files.
819  */
820 static int
821 is_a_valid_tgt_cache(const char *filepath, uid_t uid, int *retrating,
822     time_t *retexptime)
823 {
824 #ifndef WITHOUT_KERBEROS
825 	krb5_context context;
826 	krb5_principal princ;
827 	krb5_ccache ccache;
828 	krb5_error_code retval;
829 	krb5_cc_cursor curse;
830 	krb5_creds krbcred;
831 	int gotone, orating, rating, ret;
832 	struct passwd *pw;
833 	char *cp, *cp2, *pname;
834 	time_t exptime;
835 
836 	/* Find a likely name for the uid principal. */
837 	pw = getpwuid(uid);
838 
839 	/*
840 	 * Do a bunch of krb5 library stuff to try and determine if
841 	 * this file is a credentials cache with an appropriate TGT
842 	 * in it.
843 	 */
844 	retval = krb5_init_context(&context);
845 	if (retval != 0)
846 		return (0);
847 	retval = krb5_cc_resolve(context, filepath, &ccache);
848 	if (retval != 0) {
849 		krb5_free_context(context);
850 		return (0);
851 	}
852 	ret = 0;
853 	orating = 0;
854 	exptime = 0;
855 	retval = krb5_cc_start_seq_get(context, ccache, &curse);
856 	if (retval == 0) {
857 		while ((retval = krb5_cc_next_cred(context, ccache, &curse,
858 		    &krbcred)) == 0) {
859 			gotone = 0;
860 			rating = 0;
861 			retval = krb5_unparse_name(context, krbcred.server,
862 			    &pname);
863 			if (retval == 0) {
864 				cp = strchr(pname, '/');
865 				if (cp != NULL) {
866 					*cp++ = '\0';
867 					if (strcmp(pname, "krbtgt") == 0 &&
868 					    krbcred.times.endtime > time(NULL)
869 					    ) {
870 						gotone = 1;
871 						/*
872 						 * Test to see if this is a
873 						 * tgt for cross-realm auth.
874 						 * Rate it higher, if it is not.
875 						 */
876 						cp2 = strchr(cp, '@');
877 						if (cp2 != NULL) {
878 							*cp2++ = '\0';
879 							if (strcmp(cp, cp2) ==
880 							    0)
881 								rating++;
882 						}
883 					}
884 				}
885 				free(pname);
886 			}
887 			if (gotone != 0) {
888 				retval = krb5_unparse_name(context,
889 				    krbcred.client, &pname);
890 				if (retval == 0) {
891 					cp = strchr(pname, '@');
892 					if (cp != NULL) {
893 						*cp++ = '\0';
894 						if (pw != NULL && strcmp(pname,
895 						    pw->pw_name) == 0)
896 							rating++;
897 						if (strchr(pname, '/') == NULL)
898 							rating++;
899 						if (pref_realm[0] != '\0' &&
900 						    strcmp(cp, pref_realm) == 0)
901 							rating++;
902 					}
903 				}
904 				free(pname);
905 				if (rating > orating) {
906 					orating = rating;
907 					exptime = krbcred.times.endtime;
908 				} else if (rating == orating &&
909 				    krbcred.times.endtime > exptime)
910 					exptime = krbcred.times.endtime;
911 				ret = 1;
912 			}
913 			krb5_free_cred_contents(context, &krbcred);
914 		}
915 		krb5_cc_end_seq_get(context, ccache, &curse);
916 	}
917 	krb5_cc_close(context, ccache);
918 	krb5_free_context(context);
919 	if (ret != 0) {
920 		*retrating = orating;
921 		*retexptime = exptime;
922 	}
923 	return (ret);
924 #else /* WITHOUT_KERBEROS */
925 	return (0);
926 #endif /* !WITHOUT_KERBEROS */
927 }
928 
929