xref: /illumos-gate/usr/src/cmd/nscd/cache.h (revision 150d2c5288c645a1c1a7d2bee61199a3729406c7)
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  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
23  * Use is subject to license terms.
24  */
25 
26 #ifndef _NSCD_H
27 #define	_NSCD_H
28 
29 #pragma ident	"%Z%%M%	%I%	%E% SMI"
30 
31 /*
32  * This is a private header file.  Applications should not directly include
33  * this file.
34  */
35 
36 #ifdef	__cplusplus
37 extern "C" {
38 #endif
39 
40 #include <sys/avl.h>
41 #include <thread.h>
42 #include <synch.h>
43 #include <nss_dbdefs.h>
44 #include "getxby_door.h"
45 #include "nscd_common.h"
46 #include "nscd_config.h"
47 
48 /*
49  * OR'D in by server to call self for updates
50  */
51 #define	UPDATEBIT	(1<<30)
52 #define	MASKUPDATEBIT(a) ((~UPDATEBIT)&(a))
53 
54 /*
55  * debug levels
56  */
57 #define	DBG_OFF		0
58 #define	DBG_CANT_FIND	2
59 #define	DBG_NETLOOKUPS	4
60 #define	DBG_ALL		6
61 
62 /*
63  * Max size name we allow to be passed to avoid
64  * buffer overflow problems
65  */
66 #define	NSCDMAXNAMELEN	255
67 
68 /*
69  * cached entry status
70  */
71 #define	ST_UPDATE_PENDING	0x1
72 #define	ST_LOOKUP_PENDING	0x2
73 #define	ST_PENDING		(ST_LOOKUP_PENDING | ST_UPDATE_PENDING)
74 #define	ST_NEW_ENTRY		0x4
75 #define	ST_DISCARD		0x8
76 
77 /*
78  * Cache eviction start and stop levels
79  */
80 #define	_NSC_EVICTION_START_LEVEL	90
81 #define	_NSC_EVICTION_SAFE_LEVEL	80
82 
83 /*
84  * other internal constants
85  */
86 #define	_NSC_MAX_DB		2
87 #define	_NSC_PUBLIC_ACCESS	-1
88 #define	_NSC_FILE_CHECK_TIME	0	/* check always for backwards compat */
89 
90 /*
91  * Macros used for logging purposes
92  */
93 #define	yes_no(flag)	(flag == nscd_true)?"yes":"no"
94 #define	check_null(str)	(str)?str:"<null>"
95 
96 /*
97  * Macros used by compare routines
98  */
99 #define	_NSC_INT_KEY_CMP(n1, n2) \
100 	(n1 > n2)?1:((n1 == n2)?0:-1)
101 
102 #define	_NSC_GET_HITRATE(sp) \
103 	sp->hitrate = sp->pos_misses + sp->neg_misses + \
104 		sp->pos_hits + sp->neg_hits; \
105 	if (sp->hitrate > 0.0) \
106 		sp->hitrate = (100.0 * \
107 			((double)sp->pos_hits + \
108 			(double)sp->neg_hits)) / sp->hitrate;
109 
110 /*
111  * nsc_lookup action
112  */
113 typedef enum {
114 	_NSC_NSLOOKUP = 0,
115 	_NSC_WAIT,
116 	_NSC_USECACHED
117 } nsc_action_t;
118 
119 /*
120  * Structure to handle waiting for pending name service requests
121  */
122 typedef struct waiter {
123 	cond_t		w_waitcv;
124 	uint8_t		*w_key;
125 	struct waiter	*w_next, *w_prev;
126 } waiter_t;
127 
128 /*
129  *  What each entry in the nameserver cache looks like.
130  */
131 
132 typedef struct nsc_entry_stat {
133 	uint_t		hits;		/* number of hits */
134 	uint8_t		status;		/* activity status */
135 	time_t		timestamp;	/* expiry time */
136 	int 		refcount;	/* reference count */
137 } nsc_entry_stat_t;
138 
139 typedef struct nsc_entry {
140 	avl_node_t		avl_link;	/* libavl requirement */
141 	struct nsc_entry 	*qnext;		/* next on pqueue */
142 	struct nsc_entry 	*qprev;		/* prev on pqueue */
143 	nsc_entry_stat_t	stats;		/* entry's statistics */
144 	nss_XbyY_key_t		key;		/* entry's key */
145 	void			*buffer;	/* data buffer */
146 	size_t			bufsize;	/* data buffer length */
147 } nsc_entry_t;
148 
149 typedef struct nsc_keephot {
150 	void	*ptr;
151 	uint_t	num;
152 } nsc_keephot_t;
153 
154 /*
155  * Macros used by hash table
156  *
157  * _NSC_HTSIZE_PRIMES are prime numbers that are used as hash table
158  * sizes when hash table type is nsc_ht_prime. For hash tables of
159  * type nsc_ht_power2, the size is automatically calculated.
160  * Number of primes listed below is _NSC_HTSIZE_NUM_SLOTS + 1.
161  * Each number (except the first) is a prime closest to a
162  * power of 2 in increasing order. Ex: 509 is the closest prime to
163  * 512 (2**9), 1021 is closest to 1024 (2**10), and so on.
164  * The first prime is chosen as 211 for historical reasons.
165  */
166 #define	_NSC_INIT_HTSIZE_PRIME	211
167 #define	_NSC_INIT_HTSIZE_POWER2	256
168 #define	_NSC_INIT_HTSIZE_SLOT_VALUE	2896
169 #define	_NSC_HTSIZE_NUM_SLOTS	10
170 #define	_NSC_HTSIZE_PRIMES	211, 509, 1021, 2053, 4099, 8191, \
171 				16381, 32771, 65537, 131071, 262147
172 
173 #define	_NSC_DB_CES_KEY(ptr) \
174 		((ptr)->db_type == nsc_key_ces)
175 #define	_NSC_DB_CIS_KEY(ptr) \
176 		((ptr)->db_type == nsc_key_cis)
177 #define	_NSC_DB_STR_KEY(ptr) \
178 		_NSC_DB_CES_KEY(ptr) || _NSC_DB_CIS_KEY(ptr)
179 #define	_NSC_DB_INT_KEY(ptr) \
180 		((ptr)->db_type == nsc_key_int)
181 
182 /*
183  * cache backend param group (global)
184  */
185 #define	NSCD_CFG_GROUP_INFO_GLOBAL_CACHE	{1, 0x0001}
186 typedef struct nscd_cfg_global_cache {
187 	nscd_cfg_group_info_t	gi;	/* config requirement */
188 	nscd_bool_t	enable;
189 } nscd_cfg_global_cache_t;
190 
191 #define	NSCD_CFG_GLOBAL_CACHE_DEFAULTS \
192 	{ NSCD_CFG_GROUP_INFO_GLOBAL_CACHE, nscd_true }
193 
194 /*
195  * cache backend param group (per database)
196  */
197 #define	NSCD_CFG_GROUP_INFO_CACHE	{12, 0x0fff}
198 typedef struct nscd_cfg_cache {
199 	nscd_cfg_group_info_t	gi;	/* config requirement */
200 	nscd_bool_t	enable;		/* if false return NOSERVER */
201 	nscd_bool_t	per_user;	/* if true per user access */
202 	nscd_bool_t	avoid_ns;	/* if true avoid name service */
203 	nscd_bool_t	check_files;	/* if true check file */
204 	int		check_interval;	/* check interval */
205 	int		pos_ttl;	/* time to live for +ve entries */
206 	int		neg_ttl;	/* time to live for -ve entries */
207 	int		keephot;	/* keep hot count */
208 	int		hint_size;	/* size to return for a GETHINTS */
209 	ulong_t		maxentries;	/* maximum entries allowed */
210 	int		suggestedsize;	/* obsolete */
211 	nscd_bool_t	old_data_ok;	/* obsolete */
212 } nscd_cfg_cache_t;
213 
214 #define	NSCD_CFG_CACHE_DEFAULTS \
215 	{ \
216 		NSCD_CFG_GROUP_INFO_CACHE, \
217 		nscd_true, nscd_false, nscd_false, nscd_true, \
218 		_NSC_FILE_CHECK_TIME, 600, 10, 0, 1 << 11, 0, \
219 		0,  nscd_false \
220 	}
221 
222 /*
223  * cache backend stat group (per database)
224  */
225 #define	NSCD_CFG_STAT_GROUP_INFO_CACHE	{9, 0x01ff}
226 typedef struct nscd_cfg_stat_cache {
227 	nscd_cfg_group_info_t	gi;	/* config requirement */
228 	ulong_t	pos_hits;		/* hits on +ve entries */
229 	ulong_t	neg_hits;		/* hits on -ve entries */
230 	ulong_t	pos_misses;		/* misses on +ve entries */
231 	ulong_t	neg_misses;		/* misses on -ve entries */
232 	ulong_t	entries;		/* count of cache entries */
233 	ulong_t	drop_count;		/* cache queries dropped */
234 	ulong_t	wait_count;		/* cache queries queued */
235 	ulong_t	invalidate_count;	/* count for cache invalidation */
236 	double	hitrate;		/* computed from other fields */
237 } nscd_cfg_stat_cache_t;
238 
239 typedef struct nsc_db {
240 	/*
241 	 * Data
242 	 */
243 	avl_tree_t	tree;
244 	nsc_entry_t	**htable;
245 	nsc_entry_t	*qhead;
246 	nsc_entry_t	*qtail;
247 	nsc_entry_t	*reap_node;
248 	int 		callnumber;
249 	int		dbop;
250 	char 		*name;
251 	mutex_t		db_mutex;
252 	int		htsize;
253 	enum hash_type {
254 		nsc_ht_default = 0,
255 		nsc_ht_prime = 1,
256 		nsc_ht_power2 = 2
257 	} hash_type;
258 	enum db_type {
259 		nsc_key_ces = 0,
260 		nsc_key_cis = 1,
261 		nsc_key_int = 2,
262 		nsc_key_other = 3
263 	} db_type;
264 	/*
265 	 * Methods
266 	 */
267 	uint_t (*gethash)(nss_XbyY_key_t *, int);
268 	int (*compar)(const void *, const void *);
269 	void (*getlogstr)(char *, char *, size_t, nss_XbyY_args_t *);
270 	/*
271 	 * Config
272 	 */
273 	nscd_cfg_cache_t	cfg;
274 	time_t			cfg_mtime;
275 } nsc_db_t;
276 
277 
278 typedef struct nsc_ctx {
279 	char 		*dbname;		/* cache name */
280 	nscd_cfg_stat_cache_t	stats;		/* statistics */
281 	nscd_cfg_cache_t	cfg;		/* configs */
282 	time_t		cfg_mtime;		/* config last modified time */
283 	rwlock_t	cfg_rwlp;		/* config rwlock */
284 	mutex_t		stats_mutex;		/* stats mutex */
285 	mutex_t		file_mutex;		/* file mutex */
286 	time_t		file_mtime;		/* file last modified time */
287 	time_t		file_chktime; 		/* file last checked time */
288 	off_t		file_size;		/* file size at last check */
289 	ino_t		file_ino;		/* file inode at last check */
290 	const char 	*file_name;		/* filename for check_files */
291 	int		db_count;		/* number of caches */
292 	nsc_db_t 	*nsc_db[_NSC_MAX_DB];	/* caches */
293 	waiter_t	wait;			/* lookup wait CV */
294 	sema_t		throttle_sema;		/* throttle lookups */
295 	sema_t		revalidate_sema;	/* revalidation threads */
296 	nscd_bool_t	revalidate_on;		/* reval. thread started */
297 	nscd_bool_t	reaper_on;		/* reaper thread started */
298 } nsc_ctx_t;
299 
300 typedef struct nsc_lookup_args {
301 	nsc_ctx_t	*ctx;
302 	nsc_db_t	*nscdb;
303 	void		*buffer;
304 	size_t		bufsize;
305 } nsc_lookup_args_t;
306 
307 #define	CACHE_CTX_COUNT	20
308 
309 /* Context initialization */
310 extern void passwd_init_ctx(nsc_ctx_t *);
311 extern void group_init_ctx(nsc_ctx_t *);
312 extern void host_init_ctx(nsc_ctx_t *);
313 extern void ipnode_init_ctx(nsc_ctx_t *);
314 extern void exec_init_ctx(nsc_ctx_t *);
315 extern void prof_init_ctx(nsc_ctx_t *);
316 extern void user_init_ctx(nsc_ctx_t *);
317 extern void ether_init_ctx(nsc_ctx_t *);
318 extern void rpc_init_ctx(nsc_ctx_t *);
319 extern void proto_init_ctx(nsc_ctx_t *);
320 extern void net_init_ctx(nsc_ctx_t *);
321 extern void bootp_init_ctx(nsc_ctx_t *);
322 extern void auuser_init_ctx(nsc_ctx_t *);
323 extern void auth_init_ctx(nsc_ctx_t *);
324 extern void serv_init_ctx(nsc_ctx_t *);
325 extern void netmask_init_ctx(nsc_ctx_t *);
326 extern void printer_init_ctx(nsc_ctx_t *);
327 extern void project_init_ctx(nsc_ctx_t *);
328 extern void tnrhtp_init_ctx(nsc_ctx_t *);
329 extern void tnrhdb_init_ctx(nsc_ctx_t *);
330 
331 /* Functions used to throttle threads */
332 extern int nscd_wait(waiter_t *, mutex_t *, uint8_t *);
333 extern int nscd_signal(waiter_t *, uint8_t *);
334 
335 /* Cache creation and initialization */
336 extern nscd_rc_t init_cache();
337 extern nsc_db_t *make_cache(enum db_type, int, char *,
338 	int (*compar) (const void *, const void *),
339 	void (*getlogstr)(char *, char *, size_t, nss_XbyY_args_t *),
340 	uint_t (*gethash)(nss_XbyY_key_t *, int),
341 	enum hash_type, int);
342 
343 /* Cache backend lookup */
344 extern void nsc_lookup(nsc_lookup_args_t *, int);
345 
346 /* Cache backend info */
347 extern void nsc_info(nsc_ctx_t *, char *, nscd_cfg_cache_t cfg[],
348 		nscd_cfg_stat_cache_t stats[]);
349 #ifdef NSCD_DEBUG
350 extern int nsc_dump(char *, int);
351 #endif	/* NSCD_DEBUG */
352 
353 /* Cache invalidate */
354 extern void nsc_invalidate(nsc_ctx_t *, char *, nsc_ctx_t **);
355 
356 /* Keep hot functions */
357 extern nsc_keephot_t *maken(int);
358 extern void *insertn(nsc_keephot_t *, uint_t, void *);
359 
360 /* hash related routines */
361 extern uint_t cis_gethash(const char *, int);
362 extern uint_t ces_gethash(const char *, int);
363 extern uint_t db_gethash(const void *, int, int);
364 
365 extern void leave(int n);
366 extern int get_cache_idx(char *);
367 
368 #ifdef	__cplusplus
369 }
370 #endif
371 
372 #endif	/* _NSCD_H */
373