nscd/nscd.h

   1 /* Copyright (c) 1998, 1999, 2000, 2001, 2003, 2004, 2005, 2006
   2    Free Software Foundation, Inc.
   3    This file is part of the GNU C Library.
   4    Contributed by Thorsten Kukuk <kukuk@suse.de>, 1998.
   5
   6    The GNU C Library is free software; you can redistribute it and/or
   7    modify it under the terms of the GNU Lesser General Public
   8    License as published by the Free Software Foundation; either
   9    version 2.1 of the License, or (at your option) any later version.
  10
  11    The GNU C Library is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14    Lesser General Public License for more details.
  15
  16    You should have received a copy of the GNU Lesser General Public
  17    License along with the GNU C Library; if not, write to the Free
  18    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
  19    02111-1307 USA.  */
  20
  21 #ifndef _NSCD_H
  22 #define _NSCD_H 1
  23
  24 #include <pthread.h>
  25 #include <stdbool.h>
  26 #include <time.h>
  27 #include <sys/uio.h>
  28
  29 /* The declarations for the request and response types are in the file
  30    "nscd-client.h", which should contain everything needed by client
  31    functions.  */
  32 #include "nscd-client.h"
  33
  34
  35 /* Handle databases.  */
  36 typedef enum
  37 {
  38   pwddb,
  39   grpdb,
  40   hstdb,
  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 /* Structure describing dynamic part of one database.  */
  58 struct database_dyn
  59 {
  60   pthread_rwlock_t lock;
  61
  62   int enabled;
  63   int check_file;
  64   int persistent;
  65   int shared;
  66   int propagate;
  67   size_t max_db_size;
  68   const char *filename;
  69   const char *db_filename;
  70   time_t file_mtime;
  71   size_t suggested_module;
  72
  73   unsigned long int postimeout; /* In seconds.  */
  74   unsigned long int negtimeout; /* In seconds.  */
  75
  76   int wr_fd;                    /* Writable file descriptor.  */
  77   int ro_fd;                    /* Unwritable file descriptor.  */
  78
  79   const struct iovec *disabled_iov;
  80
  81   struct database_pers_head *head;
  82   char *data;
  83   size_t memsize;
  84   pthread_mutex_t memlock;
  85   bool mmap_used;
  86   bool last_alloc_failed;
  87 };
  88
  89
  90 /* Paths of the file for the persistent storage.  */
  91 #define _PATH_NSCD_PASSWD_DB    "/var/db/nscd/passwd"
  92 #define _PATH_NSCD_GROUP_DB     "/var/db/nscd/group"
  93 #define _PATH_NSCD_HOSTS_DB     "/var/db/nscd/hosts"
  94
  95 /* Path used when not using persistent storage.  */
  96 #define _PATH_NSCD_XYZ_DB_TMP   "/var/run/nscd/dbXXXXXX"
  97
  98 /* Maximum alignment requirement we will encounter.  */
  99 #define BLOCK_ALIGN_LOG 3
 100 #define BLOCK_ALIGN (1 << BLOCK_ALIGN_LOG)
 101 #define BLOCK_ALIGN_M1 (BLOCK_ALIGN - 1)
 102
 103 /* Default value for the maximum size of the database files.  */
 104 #define DEFAULT_MAX_DB_SIZE     (32 * 1024 * 1024)
 105
 106 /* Number of bytes of data we initially reserve for each hash table bucket.  */
 107 #define DEFAULT_DATASIZE_PER_BUCKET 1024
 108
 109
 110 /* Global variables.  */
 111 extern struct database_dyn dbs[lastdb];
 112 extern const char *dbnames[lastdb];
 113 extern const char *serv2str[LASTREQ];
 114
 115 extern const struct iovec pwd_iov_disabled;
 116 extern const struct iovec grp_iov_disabled;
 117 extern const struct iovec hst_iov_disabled;
 118
 119
 120 /* Initial number of threads to run.  */
 121 extern int nthreads;
 122 /* Maximum number of threads to use.  */
 123 extern int max_nthreads;
 124
 125 /* User name to run server processes as.  */
 126 extern const char *server_user;
 127
 128 /* Name and UID of user who is allowed to request statistics.  */
 129 extern const char *stat_user;
 130 extern uid_t stat_uid;
 131
 132 /* Time the server was started.  */
 133 extern time_t start_time;
 134
 135 /* Number of times clients had to wait.  */
 136 extern unsigned long int client_queued;
 137
 138 /* Maximum needed alignment.  */
 139 extern const size_t block_align;
 140
 141 /* Number of times a value is reloaded without being used.  UINT_MAX
 142    means unlimited.  */
 143 extern unsigned int reload_count;
 144
 145 /* Pagesize minus one.  */
 146 extern uintptr_t pagesize_m1;
 147
 148 /* Nonzero if paranoia mode is enabled.  */
 149 extern int paranoia;
 150 /* Time after which the process restarts.  */
 151 extern time_t restart_time;
 152 /* How much time between restarts.  */
 153 extern time_t restart_interval;
 154 /* Old current working directory.  */
 155 extern const char *oldcwd;
 156 /* Old user and group ID.  */
 157 extern uid_t old_uid;
 158 extern gid_t old_gid;
 159
 160
 161 /* Prototypes for global functions.  */
 162
 163 /* nscd.c */
 164 extern void termination_handler (int signum) __attribute__ ((__noreturn__));
 165 extern int nscd_open_socket (void);
 166
 167 /* connections.c */
 168 extern void nscd_init (void);
 169 extern void close_sockets (void);
 170 extern void start_threads (void) __attribute__ ((__noreturn__));
 171
 172 /* nscd_conf.c */
 173 extern int nscd_parse_file (const char *fname,
 174                             struct database_dyn dbs[lastdb]);
 175
 176 /* nscd_stat.c */
 177 extern void send_stats (int fd, struct database_dyn dbs[lastdb]);
 178 extern int receive_print_stats (void) __attribute__ ((__noreturn__));
 179
 180 /* cache.c */
 181 extern struct datahead *cache_search (request_type, void *key, size_t len,
 182                                       struct database_dyn *table,
 183                                       uid_t owner);
 184 extern int cache_add (int type, const void *key, size_t len,
 185                       struct datahead *packet, bool first,
 186                       struct database_dyn *table, uid_t owner);
 187 extern void prune_cache (struct database_dyn *table, time_t now);
 188
 189 /* pwdcache.c */
 190 extern void addpwbyname (struct database_dyn *db, int fd, request_header *req,
 191                          void *key, uid_t uid);
 192 extern void addpwbyuid (struct database_dyn *db, int fd, request_header *req,
 193                         void *key, uid_t uid);
 194 extern void readdpwbyname (struct database_dyn *db, struct hashentry *he,
 195                            struct datahead *dh);
 196 extern void readdpwbyuid (struct database_dyn *db, struct hashentry *he,
 197                           struct datahead *dh);
 198
 199 /* grpcache.c */
 200 extern void addgrbyname (struct database_dyn *db, int fd, request_header *req,
 201                          void *key, uid_t uid);
 202 extern void addgrbygid (struct database_dyn *db, int fd, request_header *req,
 203                         void *key, uid_t uid);
 204 extern void readdgrbyname (struct database_dyn *db, struct hashentry *he,
 205                            struct datahead *dh);
 206 extern void readdgrbygid (struct database_dyn *db, struct hashentry *he,
 207                           struct datahead *dh);
 208
 209 /* hstcache.c */
 210 extern void addhstbyname (struct database_dyn *db, int fd, request_header *req,
 211                           void *key, uid_t uid);
 212 extern void addhstbyaddr (struct database_dyn *db, int fd, request_header *req,
 213                           void *key, uid_t uid);
 214 extern void addhstbynamev6 (struct database_dyn *db, int fd,
 215                             request_header *req, void *key, uid_t uid);
 216 extern void addhstbyaddrv6 (struct database_dyn *db, int fd,
 217                             request_header *req, void *key, uid_t uid);
 218 extern void readdhstbyname (struct database_dyn *db, struct hashentry *he,
 219                             struct datahead *dh);
 220 extern void readdhstbyaddr (struct database_dyn *db, struct hashentry *he,
 221                             struct datahead *dh);
 222 extern void readdhstbynamev6 (struct database_dyn *db, struct hashentry *he,
 223                               struct datahead *dh);
 224 extern void readdhstbyaddrv6 (struct database_dyn *db, struct hashentry *he,
 225                               struct datahead *dh);
 226
 227 /* aicache.c */
 228 extern void addhstai (struct database_dyn *db, int fd, request_header *req,
 229                       void *key, uid_t uid);
 230 extern void readdhstai (struct database_dyn *db, struct hashentry *he,
 231                         struct datahead *dh);
 232
 233
 234 /* initgrcache.c */
 235 extern void addinitgroups (struct database_dyn *db, int fd,
 236                            request_header *req, void *key, uid_t uid);
 237 extern void readdinitgroups (struct database_dyn *db, struct hashentry *he,
 238                              struct datahead *dh);
 239
 240 /* mem.c */
 241 extern void *mempool_alloc (struct database_dyn *db, size_t len);
 242 extern void gc (struct database_dyn *db);
 243
 244
 245 /* nscd_setup_thread.c */
 246 extern void setup_thread (struct database_dyn *db);
 247
 248
 249 /* Special version of TEMP_FAILURE_RETRY for functions returning error
 250    values.  */
 251 #define TEMP_FAILURE_RETRY_VAL(expression) \
 252   (__extension__                                                              \
 253     ({ long int __result;                                                     \
 254        do __result = (long int) (expression);                                 \
 255        while (__result == EINTR);                                             \
 256        __result; }))
 257
 258 #endif /* nscd.h */