nscd/nscd.h

   1 /* Copyright (c) 1998-2001, 2003-2009, 2011, 2012 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998.
   4
   5    The GNU C Library is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU Lesser General Public
   7    License as published by the Free Software Foundation; either
   8    version 2.1 of the License, or (at your option) any later version.
   9
  10    The GNU C Library is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13    Lesser General Public License for more details.
  14
  15    You should have received a copy of the GNU Lesser General Public
  16    License along with the GNU C Library; if not, see
  17    <http://www.gnu.org/licenses/>.  */
  18
  19 #ifndef _NSCD_H
  20 #define _NSCD_H 1
  21
  22 #include <pthread.h>
  23 #include <stdbool.h>
  24 #include <time.h>
  25 #include <sys/uio.h>
  26
  27 /* The declarations for the request and response types are in the file
  28    "nscd-client.h", which should contain everything needed by client
  29    functions.  */
  30 #include "nscd-client.h"
  31
  32
  33 /* Handle databases.  */
  34 typedef enum
  35 {
  36   pwddb,
  37   grpdb,
  38   hstdb,
  39   servdb,
  40   netgrdb,
  41   lastdb
  42 } dbtype;
  43
  44
  45 /* Default limit on the number of times a value gets reloaded without
  46    being used in the meantime.  NSCD does not throw a value out as
  47    soon as it times out.  It tries to reload the value from the
  48    server.  Only if the value has not been used for so many rounds it
  49    is removed.  */
  50 #define DEFAULT_RELOAD_LIMIT 5
  51
  52
  53 /* Time before restarting the process in paranoia mode.  */
  54 #define RESTART_INTERVAL (60 * 60)
  55
  56
  57 /* Stack size for worker threads.  */
  58 #define NSCD_THREAD_STACKSIZE 1024 * 1024 * (sizeof (void *) / 4)
  59
  60 /* Maximum size of stack frames we allow the thread to use.  We use
  61    80% of the thread stack size.  */
  62 #define MAX_STACK_USE ((8 * NSCD_THREAD_STACKSIZE) / 10)
  63
  64
  65 /* Registered filename used to fill database.  */
  66 struct traced_file
  67 {
  68   time_t mtime;
  69   struct traced_file *next;
  70   int call_res_init;
  71   int inotify_descr;
  72   char fname[];
  73 };
  74
  75
  76 /* Structure describing dynamic part of one database.  */
  77 struct database_dyn
  78 {
  79   pthread_rwlock_t lock;
  80   pthread_cond_t prune_cond;
  81   pthread_mutex_t prune_lock;
  82   pthread_mutex_t prune_run_lock;
  83   time_t wakeup_time;
  84
  85   int enabled;
  86   int check_file;
  87   int clear_cache;
  88   int persistent;
  89   int shared;
  90   int propagate;
  91   struct traced_file *traced_files;
  92   const char *db_filename;
  93   time_t file_mtime;
  94   size_t suggested_module;
  95   size_t max_db_size;
  96
  97   unsigned long int postimeout; /* In seconds.  */
  98   unsigned long int negtimeout; /* In seconds.  */
  99
 100   int wr_fd;                    /* Writable file descriptor.  */
 101   int ro_fd;                    /* Unwritable file descriptor.  */
 102
 103   const struct iovec *disabled_iov;
 104
 105   struct database_pers_head *head;
 106   char *data;
 107   size_t memsize;
 108   pthread_mutex_t memlock;
 109   bool mmap_used;
 110   bool last_alloc_failed;
 111 };
 112
 113
 114 /* Paths of the file for the persistent storage.  */
 115 #define _PATH_NSCD_PASSWD_DB    "/var/db/nscd/passwd"
 116 #define _PATH_NSCD_GROUP_DB     "/var/db/nscd/group"
 117 #define _PATH_NSCD_HOSTS_DB     "/var/db/nscd/hosts"
 118 #define _PATH_NSCD_SERVICES_DB  "/var/db/nscd/services"
 119 #define _PATH_NSCD_NETGROUP_DB  "/var/db/nscd/netgroup"
 120
 121 /* Path used when not using persistent storage.  */
 122 #define _PATH_NSCD_XYZ_DB_TMP   "/var/run/nscd/dbXXXXXX"
 123
 124 /* Maximum alignment requirement we will encounter.  */
 125 #define BLOCK_ALIGN_LOG 3
 126 #define BLOCK_ALIGN (1 << BLOCK_ALIGN_LOG)
 127 #define BLOCK_ALIGN_M1 (BLOCK_ALIGN - 1)
 128
 129 /* Default value for the maximum size of the database files.  */
 130 #define DEFAULT_MAX_DB_SIZE     (32 * 1024 * 1024)
 131
 132 /* Number of bytes of data we initially reserve for each hash table bucket.  */
 133 #define DEFAULT_DATASIZE_PER_BUCKET 1024
 134
 135 /* Default module of hash table.  */
 136 #define DEFAULT_SUGGESTED_MODULE 211
 137
 138
 139 /* Number of seconds between two cache pruning runs if we do not have
 140    better information when it is really needed.  */
 141 #define CACHE_PRUNE_INTERVAL    15
 142
 143
 144 /* Global variables.  */
 145 extern struct database_dyn dbs[lastdb] attribute_hidden;
 146 extern const char *const dbnames[lastdb];
 147 extern const char *const serv2str[LASTREQ];
 148
 149 extern const struct iovec pwd_iov_disabled;
 150 extern const struct iovec grp_iov_disabled;
 151 extern const struct iovec hst_iov_disabled;
 152 extern const struct iovec serv_iov_disabled;
 153 extern const struct iovec netgroup_iov_disabled;
 154
 155
 156 /* Initial number of threads to run.  */
 157 extern int nthreads;
 158 /* Maximum number of threads to use.  */
 159 extern int max_nthreads;
 160
 161 /* Inotify descriptor.  */
 162 extern int inotify_fd;
 163
 164 /* User name to run server processes as.  */
 165 extern const char *server_user;
 166
 167 /* Name and UID of user who is allowed to request statistics.  */
 168 extern const char *stat_user;
 169 extern uid_t stat_uid;
 170
 171 /* Time the server was started.  */
 172 extern time_t start_time;
 173
 174 /* Number of times clients had to wait.  */
 175 extern unsigned long int client_queued;
 176
 177 /* Maximum needed alignment.  */
 178 extern const size_t block_align;
 179
 180 /* Number of times a value is reloaded without being used.  UINT_MAX
 181    means unlimited.  */
 182 extern unsigned int reload_count;
 183
 184 /* Pagesize minus one.  */
 185 extern uintptr_t pagesize_m1;
 186
 187 /* Nonzero if paranoia mode is enabled.  */
 188 extern int paranoia;
 189 /* Time after which the process restarts.  */
 190 extern time_t restart_time;
 191 /* How much time between restarts.  */
 192 extern time_t restart_interval;
 193 /* Old current working directory.  */
 194 extern const char *oldcwd;
 195 /* Old user and group ID.  */
 196 extern uid_t old_uid;
 197 extern gid_t old_gid;
 198
 199
 200 /* Prototypes for global functions.  */
 201
 202 /* Wrapper functions with error checking for standard functions.  */
 203 extern void *xmalloc (size_t n)
 204   __attribute_malloc__ __attribute_alloc_size (1);
 205 extern void *xcalloc (size_t n, size_t s)
 206   __attribute_malloc__ __attribute_alloc_size (1, 2);
 207 extern void *xrealloc (void *o, size_t n)
 208   __attribute_malloc__ __attribute_alloc_size (2);
 209
 210 /* nscd.c */
 211 extern void termination_handler (int signum) __attribute__ ((__noreturn__));
 212 extern int nscd_open_socket (void);
 213
 214 /* connections.c */
 215 extern void nscd_init (void);
 216 extern void register_traced_file (size_t dbidx, struct traced_file *finfo);
 217 extern void close_sockets (void);
 218 extern void start_threads (void) __attribute__ ((__noreturn__));
 219
 220 /* nscd_conf.c */
 221 extern int nscd_parse_file (const char *fname,
 222                             struct database_dyn dbs[lastdb]);
 223
 224 /* nscd_stat.c */
 225 extern void send_stats (int fd, struct database_dyn dbs[lastdb]);
 226 extern int receive_print_stats (void) __attribute__ ((__noreturn__));
 227
 228 /* cache.c */
 229 extern struct datahead *cache_search (request_type, const void *key,
 230                                       size_t len, struct database_dyn *table,
 231                                       uid_t owner);
 232 extern int cache_add (int type, const void *key, size_t len,
 233                       struct datahead *packet, bool first,
 234                       struct database_dyn *table, uid_t owner,
 235                       bool prune_wakeup);
 236 extern time_t prune_cache (struct database_dyn *table, time_t now, int fd);
 237
 238 /* pwdcache.c */
 239 extern void addpwbyname (struct database_dyn *db, int fd, request_header *req,
 240                          void *key, uid_t uid);
 241 extern void addpwbyuid (struct database_dyn *db, int fd, request_header *req,
 242                         void *key, uid_t uid);
 243 extern time_t readdpwbyname (struct database_dyn *db, struct hashentry *he,
 244                              struct datahead *dh);
 245 extern time_t readdpwbyuid (struct database_dyn *db, struct hashentry *he,
 246                             struct datahead *dh);
 247
 248 /* grpcache.c */
 249 extern void addgrbyname (struct database_dyn *db, int fd, request_header *req,
 250                          void *key, uid_t uid);
 251 extern void addgrbygid (struct database_dyn *db, int fd, request_header *req,
 252                         void *key, uid_t uid);
 253 extern time_t readdgrbyname (struct database_dyn *db, struct hashentry *he,
 254                              struct datahead *dh);
 255 extern time_t readdgrbygid (struct database_dyn *db, struct hashentry *he,
 256                             struct datahead *dh);
 257
 258 /* hstcache.c */
 259 extern void addhstbyname (struct database_dyn *db, int fd, request_header *req,
 260                           void *key, uid_t uid);
 261 extern void addhstbyaddr (struct database_dyn *db, int fd, request_header *req,
 262                           void *key, uid_t uid);
 263 extern void addhstbynamev6 (struct database_dyn *db, int fd,
 264                             request_header *req, void *key, uid_t uid);
 265 extern void addhstbyaddrv6 (struct database_dyn *db, int fd,
 266                             request_header *req, void *key, uid_t uid);
 267 extern time_t readdhstbyname (struct database_dyn *db, struct hashentry *he,
 268                               struct datahead *dh);
 269 extern time_t readdhstbyaddr (struct database_dyn *db, struct hashentry *he,
 270                               struct datahead *dh);
 271 extern time_t readdhstbynamev6 (struct database_dyn *db, struct hashentry *he,
 272                                 struct datahead *dh);
 273 extern time_t readdhstbyaddrv6 (struct database_dyn *db, struct hashentry *he,
 274                                 struct datahead *dh);
 275
 276 /* aicache.c */
 277 extern void addhstai (struct database_dyn *db, int fd, request_header *req,
 278                       void *key, uid_t uid);
 279 extern time_t readdhstai (struct database_dyn *db, struct hashentry *he,
 280                           struct datahead *dh);
 281
 282
 283 /* initgrcache.c */
 284 extern void addinitgroups (struct database_dyn *db, int fd,
 285                            request_header *req, void *key, uid_t uid);
 286 extern time_t readdinitgroups (struct database_dyn *db, struct hashentry *he,
 287                                struct datahead *dh);
 288
 289 /* servicecache.c */
 290 extern void addservbyname (struct database_dyn *db, int fd,
 291                            request_header *req, void *key, uid_t uid);
 292 extern time_t readdservbyname (struct database_dyn *db, struct hashentry *he,
 293                                struct datahead *dh);
 294 extern void addservbyport (struct database_dyn *db, int fd,
 295                            request_header *req, void *key, uid_t uid);
 296 extern time_t readdservbyport (struct database_dyn *db, struct hashentry *he,
 297                                struct datahead *dh);
 298
 299 /* netgroupcache.c */
 300 extern void addinnetgr (struct database_dyn *db, int fd, request_header *req,
 301                         void *key, uid_t uid);
 302 extern time_t readdinnetgr (struct database_dyn *db, struct hashentry *he,
 303                             struct datahead *dh);
 304 extern void addgetnetgrent (struct database_dyn *db, int fd,
 305                             request_header *req, void *key, uid_t uid);
 306 extern time_t readdgetnetgrent (struct database_dyn *db, struct hashentry *he,
 307                                 struct datahead *dh);
 308
 309 /* mem.c */
 310 extern void *mempool_alloc (struct database_dyn *db, size_t len,
 311                             int data_alloc);
 312 extern void gc (struct database_dyn *db);
 313
 314
 315 /* nscd_setup_thread.c */
 316 extern int setup_thread (struct database_dyn *db);
 317
 318
 319 /* Special version of TEMP_FAILURE_RETRY for functions returning error
 320    values.  */
 321 #define TEMP_FAILURE_RETRY_VAL(expression) \
 322   (__extension__                                                              \
 323     ({ long int __result;                                                     \
 324        do __result = (long int) (expression);                                 \
 325        while (__result == EINTR);                                             \
 326        __result; }))
 327
 328 #endif /* nscd.h */