usr/src/cmd/nscd/cache.h

   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 (c) 1994, 2010, Oracle and/or its affiliates. All rights reserved.
  23  */
  24
  25 #ifndef _NSCD_H
  26 #define _NSCD_H
  27
  28 /*
  29  * This is a private header file.  Applications should not directly include
  30  * this file.
  31  */
  32
  33 #ifdef  __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 #include <sys/avl.h>
  38 #include <thread.h>
  39 #include <synch.h>
  40 #include <nss_dbdefs.h>
  41 #include "getxby_door.h"
  42 #include "nscd_common.h"
  43 #include "nscd_config.h"
  44
  45 /*
  46  * OR'D in by server to call self for updates
  47  */
  48 #define UPDATEBIT       (1<<30)
  49 #define MASKUPDATEBIT(a) ((~UPDATEBIT)&(a))
  50
  51 /*
  52  * debug levels
  53  */
  54 #define DBG_OFF         0
  55 #define DBG_CANT_FIND   2
  56 #define DBG_NETLOOKUPS  4
  57 #define DBG_ALL         6
  58
  59 /*
  60  * Max size name we allow to be passed to avoid
  61  * buffer overflow problems
  62  */
  63 #define NSCDMAXNAMELEN  255
  64
  65 /*
  66  * cached entry status
  67  */
  68 #define ST_UPDATE_PENDING       0x1
  69 #define ST_LOOKUP_PENDING       0x2
  70 #define ST_PENDING              (ST_LOOKUP_PENDING | ST_UPDATE_PENDING)
  71 #define ST_NEW_ENTRY            0x4
  72 #define ST_DISCARD              0x8
  73
  74 /*
  75  * Cache eviction start and stop levels
  76  */
  77 #define _NSC_EVICTION_START_LEVEL       90
  78 #define _NSC_EVICTION_SAFE_LEVEL        80
  79
  80 /*
  81  * other internal constants
  82  */
  83 #define _NSC_MAX_DB             3
  84 #define _NSC_PUBLIC_ACCESS      -1
  85 #define _NSC_FILE_CHECK_TIME    0       /* check always for backwards compat */
  86
  87 /*
  88  * Macros used for logging purposes
  89  */
  90 #define yes_no(flag)    (flag == nscd_true)?"yes":"no"
  91 #define check_null(str) (str)?str:"<null>"
  92
  93 /*
  94  * Macros used by compare routines
  95  */
  96 #define _NSC_INT_KEY_CMP(n1, n2) \
  97         (n1 > n2)?1:((n1 == n2)?0:-1)
  98
  99 #define _NSC_GET_HITRATE(sp) \
 100         sp->hitrate = sp->pos_misses + sp->neg_misses + \
 101                 sp->pos_hits + sp->neg_hits; \
 102         if (sp->hitrate > 0.0) \
 103                 sp->hitrate = (100.0 * \
 104                         ((double)sp->pos_hits + \
 105                         (double)sp->neg_hits)) / sp->hitrate;
 106
 107 /*
 108  * nsc_lookup action
 109  */
 110 typedef enum {
 111         _NSC_NSLOOKUP = 0,
 112         _NSC_WAIT,
 113         _NSC_USECACHED
 114 } nsc_action_t;
 115
 116 /*
 117  *  What each entry in the nameserver cache looks like.
 118  */
 119
 120 typedef struct nsc_entry_stat {
 121         uint_t          hits;           /* number of hits */
 122         uint8_t         status;         /* activity status */
 123         time_t          timestamp;      /* expiry time */
 124         int             refcount;       /* reference count */
 125 } nsc_entry_stat_t;
 126
 127 typedef struct nsc_entry {
 128         avl_node_t              avl_link;       /* libavl requirement */
 129         struct nsc_entry        *qnext;         /* next on pqueue */
 130         struct nsc_entry        *qprev;         /* prev on pqueue */
 131         nsc_entry_stat_t        stats;          /* entry's statistics */
 132         nss_XbyY_key_t          key;            /* entry's key */
 133         void                    *buffer;        /* data buffer */
 134         size_t                  bufsize;        /* data buffer length */
 135 } nsc_entry_t;
 136
 137 typedef struct nsc_keephot {
 138         void    *ptr;
 139         uint_t  num;
 140 } nsc_keephot_t;
 141
 142 /*
 143  * Structure to handle waiting for pending name service requests
 144  */
 145 typedef struct waiter {
 146         cond_t          w_waitcv;
 147         uint8_t         w_signaled;
 148         nsc_entry_t     *w_key;
 149         struct waiter   *w_next, *w_prev;
 150 } waiter_t;
 151
 152 /*
 153  * Macros used by hash table
 154  *
 155  * _NSC_HTSIZE_PRIMES are prime numbers that are used as hash table
 156  * sizes when hash table type is nsc_ht_prime. For hash tables of
 157  * type nsc_ht_power2, the size is automatically calculated.
 158  * Number of primes listed below is _NSC_HTSIZE_NUM_SLOTS + 1.
 159  * Each number (except the first) is a prime closest to a
 160  * power of 2 in increasing order. Ex: 509 is the closest prime to
 161  * 512 (2**9), 1021 is closest to 1024 (2**10), and so on.
 162  * The first prime is chosen as 211 for historical reasons.
 163  */
 164 #define _NSC_INIT_HTSIZE_PRIME  211
 165 #define _NSC_INIT_HTSIZE_POWER2 256
 166 #define _NSC_INIT_HTSIZE_SLOT_VALUE     2896
 167 #define _NSC_HTSIZE_NUM_SLOTS   10
 168 #define _NSC_HTSIZE_PRIMES      211, 509, 1021, 2053, 4099, 8191, \
 169                                 16381, 32771, 65537, 131071, 262147
 170
 171 #define _NSC_DB_CES_KEY(ptr) \
 172                 ((ptr)->db_type == nsc_key_ces)
 173 #define _NSC_DB_CIS_KEY(ptr) \
 174                 ((ptr)->db_type == nsc_key_cis)
 175 #define _NSC_DB_STR_KEY(ptr) \
 176                 _NSC_DB_CES_KEY(ptr) || _NSC_DB_CIS_KEY(ptr)
 177 #define _NSC_DB_INT_KEY(ptr) \
 178                 ((ptr)->db_type == nsc_key_int)
 179
 180 /*
 181  * cache backend param group (global)
 182  */
 183 #define NSCD_CFG_GROUP_INFO_GLOBAL_CACHE        {1, 0x0001}
 184 typedef struct nscd_cfg_global_cache {
 185         nscd_cfg_group_info_t   gi;     /* config requirement */
 186         nscd_bool_t     enable;
 187 } nscd_cfg_global_cache_t;
 188
 189 #define NSCD_CFG_GLOBAL_CACHE_DEFAULTS \
 190         { NSCD_CFG_GROUP_INFO_GLOBAL_CACHE, nscd_true }
 191
 192 /*
 193  * cache backend param group (per database)
 194  */
 195 #define NSCD_CFG_GROUP_INFO_CACHE       {12, 0x0fff}
 196 typedef struct nscd_cfg_cache {
 197         nscd_cfg_group_info_t   gi;     /* config requirement */
 198         nscd_bool_t     enable;         /* if false return NOSERVER */
 199         nscd_bool_t     per_user;       /* if true per user access */
 200         nscd_bool_t     avoid_ns;       /* if true avoid name service */
 201         nscd_bool_t     check_files;    /* if true check file */
 202         int             check_interval; /* check interval */
 203         int             pos_ttl;        /* time to live for +ve entries */
 204         int             neg_ttl;        /* time to live for -ve entries */
 205         int             keephot;        /* keep hot count */
 206         int             hint_size;      /* size to return for a GETHINTS */
 207         ulong_t         maxentries;     /* maximum entries allowed */
 208         int             suggestedsize;  /* obsolete */
 209         nscd_bool_t     old_data_ok;    /* obsolete */
 210 } nscd_cfg_cache_t;
 211
 212 #define NSCD_CFG_CACHE_DEFAULTS \
 213         { \
 214                 NSCD_CFG_GROUP_INFO_CACHE, \
 215                 nscd_true, nscd_false, nscd_false, nscd_true, \
 216                 _NSC_FILE_CHECK_TIME, 600, 10, 0, 1 << 11, 0, \
 217                 0,  nscd_false \
 218         }
 219
 220 /*
 221  * cache backend stat group (per database)
 222  */
 223 #define NSCD_CFG_STAT_GROUP_INFO_CACHE  {9, 0x01ff}
 224 typedef struct nscd_cfg_stat_cache {
 225         nscd_cfg_group_info_t   gi;     /* config requirement */
 226         ulong_t pos_hits;               /* hits on +ve entries */
 227         ulong_t neg_hits;               /* hits on -ve entries */
 228         ulong_t pos_misses;             /* misses on +ve entries */
 229         ulong_t neg_misses;             /* misses on -ve entries */
 230         ulong_t entries;                /* count of cache entries */
 231         ulong_t drop_count;             /* cache queries dropped */
 232         ulong_t wait_count;             /* cache queries queued */
 233         ulong_t invalidate_count;       /* count for cache invalidation */
 234         double  hitrate;                /* computed from other fields */
 235 } nscd_cfg_stat_cache_t;
 236
 237 typedef struct nsc_db {
 238         /*
 239          * Data
 240          */
 241         avl_tree_t      tree;
 242         nsc_entry_t     **htable;
 243         nsc_entry_t     *qhead;
 244         nsc_entry_t     *qtail;
 245         nsc_entry_t     *reap_node;
 246         int             callnumber;
 247         int             dbop;
 248         char            *name;
 249         mutex_t         db_mutex;
 250         waiter_t        db_wait;        /* lookup wait CV */
 251         int             htsize;
 252         enum hash_type {
 253                 nsc_ht_default = 0,
 254                 nsc_ht_prime = 1,
 255                 nsc_ht_power2 = 2
 256         } hash_type;
 257         enum db_type {
 258                 nsc_key_ces = 0,
 259                 nsc_key_cis = 1,
 260                 nsc_key_int = 2,
 261                 nsc_key_other = 3
 262         } db_type;
 263         /*
 264          * Methods
 265          */
 266         uint_t (*gethash)(nss_XbyY_key_t *, int);
 267         int (*compar)(const void *, const void *);
 268         void (*getlogstr)(char *, char *, size_t, nss_XbyY_args_t *);
 269         /*
 270          * Config
 271          */
 272         nscd_cfg_cache_t        cfg;
 273         time_t                  cfg_mtime;
 274 } nsc_db_t;
 275
 276
 277 typedef struct nsc_ctx {
 278         char            *dbname;                /* cache name */
 279         nscd_cfg_stat_cache_t   stats;          /* statistics */
 280         nscd_cfg_cache_t        cfg;            /* configs */
 281         time_t          cfg_mtime;              /* config last modified time */
 282         rwlock_t        cfg_rwlp;               /* config rwlock */
 283         mutex_t         stats_mutex;            /* stats mutex */
 284         mutex_t         file_mutex;             /* file mutex */
 285         time_t          file_mtime;             /* file last modified time */
 286         time_t          file_chktime;           /* file last checked time */
 287         off_t           file_size;              /* file size at last check */
 288         ino_t           file_ino;               /* file inode at last check */
 289         const char      *file_name;             /* filename for check_files */
 290         int             db_count;       /* number of caches, max _NSC_MAX_DB */
 291         nsc_db_t        *nsc_db[_NSC_MAX_DB];   /* caches */
 292         sema_t          throttle_sema;          /* throttle lookups */
 293         sema_t          revalidate_sema;        /* revalidation threads */
 294         nscd_bool_t     revalidate_on;          /* reval. thread started */
 295         nscd_bool_t     reaper_on;              /* reaper thread started */
 296 } nsc_ctx_t;
 297
 298 typedef struct nsc_lookup_args {
 299         nsc_ctx_t       *ctx;
 300         nsc_db_t        *nscdb;
 301         void            *buffer;
 302         size_t          bufsize;
 303 } nsc_lookup_args_t;
 304
 305 #define CACHE_CTX_COUNT 19
 306
 307 /* Context initialization */
 308 extern void passwd_init_ctx(nsc_ctx_t *);
 309 extern void group_init_ctx(nsc_ctx_t *);
 310 extern void host_init_ctx(nsc_ctx_t *);
 311 extern void ipnode_init_ctx(nsc_ctx_t *);
 312 extern void exec_init_ctx(nsc_ctx_t *);
 313 extern void prof_init_ctx(nsc_ctx_t *);
 314 extern void user_init_ctx(nsc_ctx_t *);
 315 extern void ether_init_ctx(nsc_ctx_t *);
 316 extern void rpc_init_ctx(nsc_ctx_t *);
 317 extern void proto_init_ctx(nsc_ctx_t *);
 318 extern void net_init_ctx(nsc_ctx_t *);
 319 extern void bootp_init_ctx(nsc_ctx_t *);
 320 extern void auth_init_ctx(nsc_ctx_t *);
 321 extern void serv_init_ctx(nsc_ctx_t *);
 322 extern void netmask_init_ctx(nsc_ctx_t *);
 323 extern void printer_init_ctx(nsc_ctx_t *);
 324 extern void project_init_ctx(nsc_ctx_t *);
 325 extern void tnrhtp_init_ctx(nsc_ctx_t *);
 326 extern void tnrhdb_init_ctx(nsc_ctx_t *);
 327
 328 /* Functions used to throttle threads */
 329 extern int nscd_wait(nsc_ctx_t *, nsc_db_t *, nsc_entry_t *);
 330 extern int nscd_signal(nsc_ctx_t *, nsc_db_t *, nsc_entry_t *);
 331
 332 /* Cache creation and initialization */
 333 extern nscd_rc_t init_cache();
 334 extern nsc_db_t *make_cache(enum db_type, int, char *,
 335         int (*compar) (const void *, const void *),
 336         void (*getlogstr)(char *, char *, size_t, nss_XbyY_args_t *),
 337         uint_t (*gethash)(nss_XbyY_key_t *, int),
 338         enum hash_type, int);
 339
 340 /* Cache backend lookup */
 341 extern void nsc_lookup(nsc_lookup_args_t *, int);
 342
 343 /* Cache backend info */
 344 extern void nsc_info(nsc_ctx_t *, char *, nscd_cfg_cache_t cfg[],
 345                 nscd_cfg_stat_cache_t stats[]);
 346 #ifdef NSCD_DEBUG
 347 extern int nsc_dump(char *, int);
 348 #endif  /* NSCD_DEBUG */
 349
 350 /* Cache invalidate */
 351 extern void nsc_invalidate(nsc_ctx_t *, char *, nsc_ctx_t **);
 352
 353 /* Keep hot functions */
 354 extern nsc_keephot_t *maken(int);
 355 extern void *insertn(nsc_keephot_t *, uint_t, void *);
 356
 357 /* hash related routines */
 358 extern uint_t cis_gethash(const char *, int);
 359 extern uint_t ces_gethash(const char *, int);
 360 extern uint_t db_gethash(const void *, int, int);
 361
 362 extern void leave(int n);
 363 extern int get_cache_idx(char *);
 364
 365 #ifdef  __cplusplus
 366 }
 367 #endif
 368
 369 #endif  /* _NSCD_H */