nscd/nscd.h

   1 /* Copyright (c) 1998-2001, 2003-2009, 2011 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, write to the Free
  17    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  18    02111-1307 USA.  */
  19
  20 #ifndef _NSCD_H
  21 #define _NSCD_H 1
  22
  23 #include <pthread.h>
  24 #include <stdbool.h>
  25 #include <time.h>
  26 #include <sys/uio.h>
  27
  28 /* The declarations for the request and response types are in the file
  29    "nscd-client.h", which should contain everything needed by client
  30    functions.  */
  31 #include "nscd-client.h"
  32
  33
  34 /* Handle databases.  */
  35 typedef enum
  36 {
  37   pwddb,
  38   grpdb,
  39   hstdb,
  40   servdb,
  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
 120 /* Path used when not using persistent storage.  */
 121 #define _PATH_NSCD_XYZ_DB_TMP   "/var/run/nscd/dbXXXXXX"
 122
 123 /* Maximum alignment requirement we will encounter.  */
 124 #define BLOCK_ALIGN_LOG 3
 125 #define BLOCK_ALIGN (1 << BLOCK_ALIGN_LOG)
 126 #define BLOCK_ALIGN_M1 (BLOCK_ALIGN - 1)
 127
 128 /* Default value for the maximum size of the database files.  */
 129 #define DEFAULT_MAX_DB_SIZE     (32 * 1024 * 1024)
 130
 131 /* Number of bytes of data we initially reserve for each hash table bucket.  */
 132 #define DEFAULT_DATASIZE_PER_BUCKET 1024
 133
 134 /* Default module of hash table.  */
 135 #define DEFAULT_SUGGESTED_MODULE 211
 136
 137
 138 /* Number of seconds between two cache pruning runs if we do not have
 139    better information when it is really needed.  */
 140 #define CACHE_PRUNE_INTERVAL    15
 141
 142
 143 /* Global variables.  */
 144 extern struct database_dyn dbs[lastdb] attribute_hidden;
 145 extern const char *const dbnames[lastdb];
 146 extern const char *const serv2str[LASTREQ];
 147
 148 extern const struct iovec pwd_iov_disabled;
 149 extern const struct iovec grp_iov_disabled;
 150 extern const struct iovec hst_iov_disabled;
 151 extern const struct iovec serv_iov_disabled;
 152
 153
 154 /* Initial number of threads to run.  */
 155 extern int nthreads;
 156 /* Maximum number of threads to use.  */
 157 extern int max_nthreads;
 158
 159 /* Inotify descriptor.  */
 160 extern int inotify_fd;
 161
 162 /* User name to run server processes as.  */
 163 extern const char *server_user;
 164
 165 /* Name and UID of user who is allowed to request statistics.  */
 166 extern const char *stat_user;
 167 extern uid_t stat_uid;
 168
 169 /* Time the server was started.  */
 170 extern time_t start_time;
 171
 172 /* Number of times clients had to wait.  */
 173 extern unsigned long int client_queued;
 174
 175 /* Maximum needed alignment.  */
 176 extern const size_t block_align;
 177
 178 /* Number of times a value is reloaded without being used.  UINT_MAX
 179    means unlimited.  */
 180 extern unsigned int reload_count;
 181
 182 /* Pagesize minus one.  */
 183 extern uintptr_t pagesize_m1;
 184
 185 /* Nonzero if paranoia mode is enabled.  */
 186 extern int paranoia;
 187 /* Time after which the process restarts.  */
 188 extern time_t restart_time;
 189 /* How much time between restarts.  */
 190 extern time_t restart_interval;
 191 /* Old current working directory.  */
 192 extern const char *oldcwd;
 193 /* Old user and group ID.  */
 194 extern uid_t old_uid;
 195 extern gid_t old_gid;
 196
 197
 198 /* Prototypes for global functions.  */
 199
 200 /* nscd.c */
 201 extern void termination_handler (int signum) __attribute__ ((__noreturn__));
 202 extern int nscd_open_socket (void);
 203
 204 /* connections.c */
 205 extern void nscd_init (void);
 206 extern void register_traced_file (size_t dbidx, struct traced_file *finfo);
 207 extern void close_sockets (void);
 208 extern void start_threads (void) __attribute__ ((__noreturn__));
 209
 210 /* nscd_conf.c */
 211 extern int nscd_parse_file (const char *fname,
 212                             struct database_dyn dbs[lastdb]);
 213
 214 /* nscd_stat.c */
 215 extern void send_stats (int fd, struct database_dyn dbs[lastdb]);
 216 extern int receive_print_stats (void) __attribute__ ((__noreturn__));
 217
 218 /* cache.c */
 219 extern struct datahead *cache_search (request_type, void *key, size_t len,
 220                                       struct database_dyn *table,
 221                                       uid_t owner);
 222 extern int cache_add (int type, const void *key, size_t len,
 223                       struct datahead *packet, bool first,
 224                       struct database_dyn *table, uid_t owner,
 225                       bool prune_wakeup);
 226 extern time_t prune_cache (struct database_dyn *table, time_t now, int fd);
 227
 228 /* pwdcache.c */
 229 extern void addpwbyname (struct database_dyn *db, int fd, request_header *req,
 230                          void *key, uid_t uid);
 231 extern void addpwbyuid (struct database_dyn *db, int fd, request_header *req,
 232                         void *key, uid_t uid);
 233 extern time_t readdpwbyname (struct database_dyn *db, struct hashentry *he,
 234                              struct datahead *dh);
 235 extern time_t readdpwbyuid (struct database_dyn *db, struct hashentry *he,
 236                             struct datahead *dh);
 237
 238 /* grpcache.c */
 239 extern void addgrbyname (struct database_dyn *db, int fd, request_header *req,
 240                          void *key, uid_t uid);
 241 extern void addgrbygid (struct database_dyn *db, int fd, request_header *req,
 242                         void *key, uid_t uid);
 243 extern time_t readdgrbyname (struct database_dyn *db, struct hashentry *he,
 244                              struct datahead *dh);
 245 extern time_t readdgrbygid (struct database_dyn *db, struct hashentry *he,
 246                             struct datahead *dh);
 247
 248 /* hstcache.c */
 249 extern void addhstbyname (struct database_dyn *db, int fd, request_header *req,
 250                           void *key, uid_t uid);
 251 extern void addhstbyaddr (struct database_dyn *db, int fd, request_header *req,
 252                           void *key, uid_t uid);
 253 extern void addhstbynamev6 (struct database_dyn *db, int fd,
 254                             request_header *req, void *key, uid_t uid);
 255 extern void addhstbyaddrv6 (struct database_dyn *db, int fd,
 256                             request_header *req, void *key, uid_t uid);
 257 extern time_t readdhstbyname (struct database_dyn *db, struct hashentry *he,
 258                               struct datahead *dh);
 259 extern time_t readdhstbyaddr (struct database_dyn *db, struct hashentry *he,
 260                               struct datahead *dh);
 261 extern time_t readdhstbynamev6 (struct database_dyn *db, struct hashentry *he,
 262                                 struct datahead *dh);
 263 extern time_t readdhstbyaddrv6 (struct database_dyn *db, struct hashentry *he,
 264                                 struct datahead *dh);
 265
 266 /* aicache.c */
 267 extern void addhstai (struct database_dyn *db, int fd, request_header *req,
 268                       void *key, uid_t uid);
 269 extern time_t readdhstai (struct database_dyn *db, struct hashentry *he,
 270                           struct datahead *dh);
 271
 272
 273 /* initgrcache.c */
 274 extern void addinitgroups (struct database_dyn *db, int fd,
 275                            request_header *req, void *key, uid_t uid);
 276 extern time_t readdinitgroups (struct database_dyn *db, struct hashentry *he,
 277                                struct datahead *dh);
 278
 279 /* servicecache.c */
 280 extern void addservbyname (struct database_dyn *db, int fd,
 281                            request_header *req, void *key, uid_t uid);
 282 extern time_t readdservbyname (struct database_dyn *db, struct hashentry *he,
 283                                struct datahead *dh);
 284 extern void addservbyport (struct database_dyn *db, int fd,
 285                            request_header *req, void *key, uid_t uid);
 286 extern time_t readdservbyport (struct database_dyn *db, struct hashentry *he,
 287                                struct datahead *dh);
 288
 289 /* mem.c */
 290 extern void *mempool_alloc (struct database_dyn *db, size_t len,
 291                             int data_alloc);
 292 extern void gc (struct database_dyn *db);
 293
 294
 295 /* nscd_setup_thread.c */
 296 extern int setup_thread (struct database_dyn *db);
 297
 298
 299 /* Special version of TEMP_FAILURE_RETRY for functions returning error
 300    values.  */
 301 #define TEMP_FAILURE_RETRY_VAL(expression) \
 302   (__extension__                                                              \
 303     ({ long int __result;                                                     \
 304        do __result = (long int) (expression);                                 \
 305        while (__result == EINTR);                                             \
 306        __result; }))
 307
 308 #endif /* nscd.h */