xref: /onnv-gate/usr/src/cmd/fs.d/nfs/mountd/netgroup.c (revision 0:68f95e015346)
1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate  * CDDL HEADER START
3*0Sstevel@tonic-gate  *
4*0Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate  * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate  * (the "License").  You may not use this file except in compliance
7*0Sstevel@tonic-gate  * with the License.
8*0Sstevel@tonic-gate  *
9*0Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate  * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate  * and limitations under the License.
13*0Sstevel@tonic-gate  *
14*0Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate  *
20*0Sstevel@tonic-gate  * CDDL HEADER END
21*0Sstevel@tonic-gate  */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate  * netgroup.c
24*0Sstevel@tonic-gate  *
25*0Sstevel@tonic-gate  * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
26*0Sstevel@tonic-gate  * Use is subject to license terms.
27*0Sstevel@tonic-gate  */
28*0Sstevel@tonic-gate 
29*0Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
30*0Sstevel@tonic-gate 
31*0Sstevel@tonic-gate #include <stdio.h>
32*0Sstevel@tonic-gate #include <stdlib.h>
33*0Sstevel@tonic-gate #include <sys/types.h>
34*0Sstevel@tonic-gate #include <string.h>
35*0Sstevel@tonic-gate #include <syslog.h>
36*0Sstevel@tonic-gate #include <sys/param.h>
37*0Sstevel@tonic-gate #include <rpc/rpc.h>
38*0Sstevel@tonic-gate #include <sys/stat.h>
39*0Sstevel@tonic-gate #include <netconfig.h>
40*0Sstevel@tonic-gate #include <netdir.h>
41*0Sstevel@tonic-gate #include <sys/file.h>
42*0Sstevel@tonic-gate #include <sys/time.h>
43*0Sstevel@tonic-gate #include <sys/errno.h>
44*0Sstevel@tonic-gate #include <sys/resource.h>
45*0Sstevel@tonic-gate #include <rpcsvc/mount.h>
46*0Sstevel@tonic-gate #include <sys/pathconf.h>
47*0Sstevel@tonic-gate #include <sys/systeminfo.h>
48*0Sstevel@tonic-gate #include <sys/utsname.h>
49*0Sstevel@tonic-gate #include <signal.h>
50*0Sstevel@tonic-gate #include <locale.h>
51*0Sstevel@tonic-gate #include <unistd.h>
52*0Sstevel@tonic-gate #include <thread.h>
53*0Sstevel@tonic-gate #include "../lib/sharetab.h"
54*0Sstevel@tonic-gate #include "mountd.h"
55*0Sstevel@tonic-gate 
56*0Sstevel@tonic-gate struct cache_entry {
57*0Sstevel@tonic-gate 	char	*cache_host;
58*0Sstevel@tonic-gate 	time_t	cache_time;
59*0Sstevel@tonic-gate 	int	cache_belong;
60*0Sstevel@tonic-gate 	char	**cache_grl;
61*0Sstevel@tonic-gate 	int	cache_grc;
62*0Sstevel@tonic-gate 	struct cache_entry *cache_next;
63*0Sstevel@tonic-gate };
64*0Sstevel@tonic-gate 
65*0Sstevel@tonic-gate static struct cache_entry *cache_head;
66*0Sstevel@tonic-gate 
67*0Sstevel@tonic-gate #define	VALID_TIME	60  /* seconds */
68*0Sstevel@tonic-gate 
69*0Sstevel@tonic-gate static rwlock_t cache_lock;	/* protect the cache chain */
70*0Sstevel@tonic-gate 
71*0Sstevel@tonic-gate static void cache_free(struct cache_entry *entry);
72*0Sstevel@tonic-gate static int cache_check(char *host, char **grl, int grc, int *belong);
73*0Sstevel@tonic-gate static void cache_enter(char *host, char **grl, int grc, int belong);
74*0Sstevel@tonic-gate 
75*0Sstevel@tonic-gate 
76*0Sstevel@tonic-gate void
77*0Sstevel@tonic-gate netgroup_init()
78*0Sstevel@tonic-gate {
79*0Sstevel@tonic-gate 	(void) rwlock_init(&cache_lock, USYNC_THREAD, NULL);
80*0Sstevel@tonic-gate }
81*0Sstevel@tonic-gate 
82*0Sstevel@tonic-gate /*
83*0Sstevel@tonic-gate  * Check whether any of the hostnames in clnames are
84*0Sstevel@tonic-gate  * members (or non-members) of the netgroups in glist.
85*0Sstevel@tonic-gate  * Since the innetgr lookup is rather expensive, the
86*0Sstevel@tonic-gate  * result is cached. The cached entry is valid only
87*0Sstevel@tonic-gate  * for VALID_TIME seconds.  This works well because
88*0Sstevel@tonic-gate  * typically these lookups occur in clusters when
89*0Sstevel@tonic-gate  * a client is mounting.
90*0Sstevel@tonic-gate  *
91*0Sstevel@tonic-gate  * Note that this routine establishes a host membership
92*0Sstevel@tonic-gate  * in a list of netgroups - we've no idea just which
93*0Sstevel@tonic-gate  * netgroup in the list it is a member of.
94*0Sstevel@tonic-gate  *
95*0Sstevel@tonic-gate  * glist is a character array containing grc strings
96*0Sstevel@tonic-gate  * representing netgroup names (optionally prefixed
97*0Sstevel@tonic-gate  * with '-'). Each string is ended with '\0'  and
98*0Sstevel@tonic-gate  * followed immediately by the next string.
99*0Sstevel@tonic-gate  */
100*0Sstevel@tonic-gate int
101*0Sstevel@tonic-gate netgroup_check(struct nd_hostservlist *clnames, char  *glist, int grc)
102*0Sstevel@tonic-gate {
103*0Sstevel@tonic-gate 	char **grl;
104*0Sstevel@tonic-gate 	char *gr;
105*0Sstevel@tonic-gate 	int nhosts = clnames->h_cnt;
106*0Sstevel@tonic-gate 	char *host0, *host;
107*0Sstevel@tonic-gate 	int i, j, n;
108*0Sstevel@tonic-gate 	int response;
109*0Sstevel@tonic-gate 	int belong = 0;
110*0Sstevel@tonic-gate 	static char *domain;
111*0Sstevel@tonic-gate 
112*0Sstevel@tonic-gate 	if (domain == NULL) {
113*0Sstevel@tonic-gate 		int	ssize;
114*0Sstevel@tonic-gate 
115*0Sstevel@tonic-gate 		domain = exmalloc(SYS_NMLN);
116*0Sstevel@tonic-gate 		ssize = sysinfo(SI_SRPC_DOMAIN, domain, SYS_NMLN);
117*0Sstevel@tonic-gate 		if (ssize > SYS_NMLN) {
118*0Sstevel@tonic-gate 			free(domain);
119*0Sstevel@tonic-gate 			domain = exmalloc(ssize);
120*0Sstevel@tonic-gate 			ssize = sysinfo(SI_SRPC_DOMAIN, domain, ssize);
121*0Sstevel@tonic-gate 		}
122*0Sstevel@tonic-gate 		/* Check for error in syscall or NULL domain name */
123*0Sstevel@tonic-gate 		if (ssize <= 1) {
124*0Sstevel@tonic-gate 			syslog(LOG_ERR, "No default domain set");
125*0Sstevel@tonic-gate 			return (0);
126*0Sstevel@tonic-gate 		}
127*0Sstevel@tonic-gate 	}
128*0Sstevel@tonic-gate 
129*0Sstevel@tonic-gate 	grl = calloc(grc, sizeof (char *));
130*0Sstevel@tonic-gate 	if (grl == NULL)
131*0Sstevel@tonic-gate 		return (0);
132*0Sstevel@tonic-gate 
133*0Sstevel@tonic-gate 	for (i = 0, gr = glist; i < grc && !belong; ) {
134*0Sstevel@tonic-gate 		/*
135*0Sstevel@tonic-gate 		 * If the netgroup name has a '-' prepended
136*0Sstevel@tonic-gate 		 * then a match of this name implies a failure
137*0Sstevel@tonic-gate 		 * instead of success.
138*0Sstevel@tonic-gate 		 */
139*0Sstevel@tonic-gate 		response = (*gr != '-') ? 1 : 0;
140*0Sstevel@tonic-gate 
141*0Sstevel@tonic-gate 		/*
142*0Sstevel@tonic-gate 		 * Subsequent names with or without a '-' (but no mix)
143*0Sstevel@tonic-gate 		 * can be grouped together for a single check.
144*0Sstevel@tonic-gate 		 */
145*0Sstevel@tonic-gate 		for (n = 0; i < grc; i++, n++, gr += strlen(gr) + 1) {
146*0Sstevel@tonic-gate 			if (response && *gr == '-' || !response && *gr != '-')
147*0Sstevel@tonic-gate 				break;
148*0Sstevel@tonic-gate 
149*0Sstevel@tonic-gate 			grl[n] = response ? gr : gr + 1;
150*0Sstevel@tonic-gate 		}
151*0Sstevel@tonic-gate 
152*0Sstevel@tonic-gate 		host0 = clnames->h_hostservs[0].h_host;
153*0Sstevel@tonic-gate 
154*0Sstevel@tonic-gate 		/*
155*0Sstevel@tonic-gate 		 * If not in cache check the netgroup for each
156*0Sstevel@tonic-gate 		 * of the hosts names (usually just one).
157*0Sstevel@tonic-gate 		 * Enter the result into the cache.
158*0Sstevel@tonic-gate 		 */
159*0Sstevel@tonic-gate 		if (!cache_check(host0, grl, n, &belong)) {
160*0Sstevel@tonic-gate 			for (j = 0; j < nhosts && !belong; j++) {
161*0Sstevel@tonic-gate 				host = clnames->h_hostservs[j].h_host;
162*0Sstevel@tonic-gate 
163*0Sstevel@tonic-gate 				if (__multi_innetgr(n, grl,
164*0Sstevel@tonic-gate 					1, &host,
165*0Sstevel@tonic-gate 					0, NULL,
166*0Sstevel@tonic-gate 					1, &domain))
167*0Sstevel@tonic-gate 					belong = 1;
168*0Sstevel@tonic-gate 			}
169*0Sstevel@tonic-gate 
170*0Sstevel@tonic-gate 			cache_enter(host0, grl, n, belong);
171*0Sstevel@tonic-gate 		}
172*0Sstevel@tonic-gate 	}
173*0Sstevel@tonic-gate 
174*0Sstevel@tonic-gate 	free(grl);
175*0Sstevel@tonic-gate 	return (belong ? response : 0);
176*0Sstevel@tonic-gate }
177*0Sstevel@tonic-gate 
178*0Sstevel@tonic-gate /*
179*0Sstevel@tonic-gate  * Free a cache entry and all entries
180*0Sstevel@tonic-gate  * further down the chain since they
181*0Sstevel@tonic-gate  * will also be expired.
182*0Sstevel@tonic-gate  */
183*0Sstevel@tonic-gate static void
184*0Sstevel@tonic-gate cache_free(struct cache_entry *entry)
185*0Sstevel@tonic-gate {
186*0Sstevel@tonic-gate 	struct cache_entry *ce, *next;
187*0Sstevel@tonic-gate 	int i;
188*0Sstevel@tonic-gate 
189*0Sstevel@tonic-gate 	for (ce = entry; ce; ce = next) {
190*0Sstevel@tonic-gate 		if (ce->cache_host)
191*0Sstevel@tonic-gate 			free(ce->cache_host);
192*0Sstevel@tonic-gate 		for (i = 0; i < ce->cache_grc; i++)
193*0Sstevel@tonic-gate 			if (ce->cache_grl[i])
194*0Sstevel@tonic-gate 				free(ce->cache_grl[i]);
195*0Sstevel@tonic-gate 		if (ce->cache_grl)
196*0Sstevel@tonic-gate 			free(ce->cache_grl);
197*0Sstevel@tonic-gate 		next = ce->cache_next;
198*0Sstevel@tonic-gate 		free(ce);
199*0Sstevel@tonic-gate 	}
200*0Sstevel@tonic-gate }
201*0Sstevel@tonic-gate 
202*0Sstevel@tonic-gate /*
203*0Sstevel@tonic-gate  * Search the entries in the cache chain looking
204*0Sstevel@tonic-gate  * for an entry with a matching hostname and group
205*0Sstevel@tonic-gate  * list.  If a match is found then return the "belong"
206*0Sstevel@tonic-gate  * value which may be 1 or 0 depending on whether the
207*0Sstevel@tonic-gate  * client is a member of the list or not.  This is
208*0Sstevel@tonic-gate  * both a positive and negative cache.
209*0Sstevel@tonic-gate  *
210*0Sstevel@tonic-gate  * Cache entries have a validity of VALID_TIME seconds.
211*0Sstevel@tonic-gate  * If we find an expired entry then blow away the entry
212*0Sstevel@tonic-gate  * and the rest of the chain since entries further down
213*0Sstevel@tonic-gate  * the chain will be expired too because we always add
214*0Sstevel@tonic-gate  * new entries to the head of the chain.
215*0Sstevel@tonic-gate  */
216*0Sstevel@tonic-gate static int
217*0Sstevel@tonic-gate cache_check(char *host, char **grl, int grc, int *belong)
218*0Sstevel@tonic-gate {
219*0Sstevel@tonic-gate 	struct cache_entry *ce, *prev;
220*0Sstevel@tonic-gate 	time_t timenow = time(NULL);
221*0Sstevel@tonic-gate 	int i;
222*0Sstevel@tonic-gate 
223*0Sstevel@tonic-gate 	(void) rw_rdlock(&cache_lock);
224*0Sstevel@tonic-gate 
225*0Sstevel@tonic-gate 	for (ce = cache_head; ce; ce = ce->cache_next) {
226*0Sstevel@tonic-gate 
227*0Sstevel@tonic-gate 		/*
228*0Sstevel@tonic-gate 		 * If we find a stale entry, there can't
229*0Sstevel@tonic-gate 		 * be any valid entries from here on.
230*0Sstevel@tonic-gate 		 * Acquire a write lock, search the chain again
231*0Sstevel@tonic-gate 		 * and delete the stale entry and all following
232*0Sstevel@tonic-gate 		 * entries.
233*0Sstevel@tonic-gate 		 */
234*0Sstevel@tonic-gate 		if (timenow > ce->cache_time) {
235*0Sstevel@tonic-gate 			(void) rw_unlock(&cache_lock);
236*0Sstevel@tonic-gate 			(void) rw_wrlock(&cache_lock);
237*0Sstevel@tonic-gate 
238*0Sstevel@tonic-gate 			for (prev = NULL, ce = cache_head; ce;
239*0Sstevel@tonic-gate 			    prev = ce, ce = ce->cache_next)
240*0Sstevel@tonic-gate 				if (timenow > ce->cache_time)
241*0Sstevel@tonic-gate 					break;
242*0Sstevel@tonic-gate 
243*0Sstevel@tonic-gate 			if (ce != NULL) {
244*0Sstevel@tonic-gate 				if (prev)
245*0Sstevel@tonic-gate 					prev->cache_next = NULL;
246*0Sstevel@tonic-gate 				else
247*0Sstevel@tonic-gate 					cache_head = NULL;
248*0Sstevel@tonic-gate 
249*0Sstevel@tonic-gate 				cache_free(ce);
250*0Sstevel@tonic-gate 			}
251*0Sstevel@tonic-gate 			(void) rw_unlock(&cache_lock);
252*0Sstevel@tonic-gate 
253*0Sstevel@tonic-gate 			return (0);
254*0Sstevel@tonic-gate 		}
255*0Sstevel@tonic-gate 		if (ce->cache_grc != grc)
256*0Sstevel@tonic-gate 			continue;	/* no match */
257*0Sstevel@tonic-gate 
258*0Sstevel@tonic-gate 		if (strcasecmp(host, ce->cache_host) != 0)
259*0Sstevel@tonic-gate 			continue;	/* no match */
260*0Sstevel@tonic-gate 
261*0Sstevel@tonic-gate 		for (i = 0; i < grc; i++)
262*0Sstevel@tonic-gate 			if (strcasecmp(ce->cache_grl[i], grl[i]) != 0)
263*0Sstevel@tonic-gate 				break;	/* no match */
264*0Sstevel@tonic-gate 		if (i < grc)
265*0Sstevel@tonic-gate 			continue;
266*0Sstevel@tonic-gate 
267*0Sstevel@tonic-gate 		*belong = ce->cache_belong;
268*0Sstevel@tonic-gate 		(void) rw_unlock(&cache_lock);
269*0Sstevel@tonic-gate 
270*0Sstevel@tonic-gate 		return (1);
271*0Sstevel@tonic-gate 	}
272*0Sstevel@tonic-gate 
273*0Sstevel@tonic-gate 	(void) rw_unlock(&cache_lock);
274*0Sstevel@tonic-gate 
275*0Sstevel@tonic-gate 	return (0);
276*0Sstevel@tonic-gate }
277*0Sstevel@tonic-gate 
278*0Sstevel@tonic-gate /*
279*0Sstevel@tonic-gate  * Put a new entry in the cache chain by
280*0Sstevel@tonic-gate  * prepending it to the front.
281*0Sstevel@tonic-gate  * If there isn't enough memory then just give up.
282*0Sstevel@tonic-gate  */
283*0Sstevel@tonic-gate static void
284*0Sstevel@tonic-gate cache_enter(char *host, char **grl, int grc, int belong)
285*0Sstevel@tonic-gate {
286*0Sstevel@tonic-gate 	struct cache_entry *entry;
287*0Sstevel@tonic-gate 	int i;
288*0Sstevel@tonic-gate 
289*0Sstevel@tonic-gate 	entry = malloc(sizeof (*entry));
290*0Sstevel@tonic-gate 	if (entry == NULL)
291*0Sstevel@tonic-gate 		return;
292*0Sstevel@tonic-gate 
293*0Sstevel@tonic-gate 	(void) memset((caddr_t)entry, 0, sizeof (*entry));
294*0Sstevel@tonic-gate 	entry->cache_host = strdup(host);
295*0Sstevel@tonic-gate 	if (entry->cache_host == NULL) {
296*0Sstevel@tonic-gate 		cache_free(entry);
297*0Sstevel@tonic-gate 		return;
298*0Sstevel@tonic-gate 	}
299*0Sstevel@tonic-gate 
300*0Sstevel@tonic-gate 	entry->cache_time = time(NULL) + VALID_TIME;
301*0Sstevel@tonic-gate 	entry->cache_belong = belong;
302*0Sstevel@tonic-gate 	entry->cache_grl = malloc(grc * sizeof (char *));
303*0Sstevel@tonic-gate 	if (entry->cache_grl == NULL) {
304*0Sstevel@tonic-gate 		cache_free(entry);
305*0Sstevel@tonic-gate 		return;
306*0Sstevel@tonic-gate 	}
307*0Sstevel@tonic-gate 
308*0Sstevel@tonic-gate 	for (i = 0; i < grc; i++) {
309*0Sstevel@tonic-gate 		entry->cache_grl[i] = strdup(grl[i]);
310*0Sstevel@tonic-gate 		if (entry->cache_grl[i] == NULL) {
311*0Sstevel@tonic-gate 			entry->cache_grc = i;
312*0Sstevel@tonic-gate 			cache_free(entry);
313*0Sstevel@tonic-gate 			return;
314*0Sstevel@tonic-gate 		}
315*0Sstevel@tonic-gate 	}
316*0Sstevel@tonic-gate 
317*0Sstevel@tonic-gate 	entry->cache_grc = grc;
318*0Sstevel@tonic-gate 
319*0Sstevel@tonic-gate 	(void) rw_wrlock(&cache_lock);
320*0Sstevel@tonic-gate 	entry->cache_next = cache_head;
321*0Sstevel@tonic-gate 	cache_head = entry;
322*0Sstevel@tonic-gate 	(void) rw_unlock(&cache_lock);
323*0Sstevel@tonic-gate }
324*0Sstevel@tonic-gate 
325*0Sstevel@tonic-gate /*
326*0Sstevel@tonic-gate  * Full cache flush
327*0Sstevel@tonic-gate  */
328*0Sstevel@tonic-gate void
329*0Sstevel@tonic-gate netgrp_cache_flush(void)
330*0Sstevel@tonic-gate {
331*0Sstevel@tonic-gate 	(void) rw_wrlock(&cache_lock);
332*0Sstevel@tonic-gate 	cache_free(cache_head);
333*0Sstevel@tonic-gate 	cache_head = NULL;
334*0Sstevel@tonic-gate 	(void) rw_unlock(&cache_lock);
335*0Sstevel@tonic-gate }
336