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   pthread_mutex_t prunelock;
  62
  63   int enabled;
  64   int check_file;
  65   int persistent;
  66   int shared;
  67   int propagate;
  68   const char filename[12];
  69   const char *db_filename;
  70   time_t file_mtime;
  71   size_t suggested_module;
  72   size_t max_db_size;
  73
  74   unsigned long int postimeout; /* In seconds.  */
  75   unsigned long int negtimeout; /* In seconds.  */
  76
  77   int wr_fd;                    /* Writable file descriptor.  */
  78   int ro_fd;                    /* Unwritable file descriptor.  */
  79
  80   const struct iovec *disabled_iov;
  81
  82   struct database_pers_head *head;
  83   char *data;
  84   size_t memsize;
  85   pthread_mutex_t memlock;
  86   bool mmap_used;
  87   bool last_alloc_failed;
  88 };
  89
  90
  91 /* Paths of the file for the persistent storage.  */
  92 #define _PATH_NSCD_PASSWD_DB    "/var/db/nscd/passwd"
  93 #define _PATH_NSCD_GROUP_DB     "/var/db/nscd/group"
  94 #define _PATH_NSCD_HOSTS_DB     "/var/db/nscd/hosts"
  95
  96 /* Path used when not using persistent storage.  */
  97 #define _PATH_NSCD_XYZ_DB_TMP   "/var/run/nscd/dbXXXXXX"
  98
  99 /* Maximum alignment requirement we will encounter.  */
 100 #define BLOCK_ALIGN_LOG 3
 101 #define BLOCK_ALIGN (1 << BLOCK_ALIGN_LOG)
 102 #define BLOCK_ALIGN_M1 (BLOCK_ALIGN - 1)
 103
 104 /* Default value for the maximum size of the database files.  */
 105 #define DEFAULT_MAX_DB_SIZE     (32 * 1024 * 1024)
 106
 107 /* Number of bytes of data we initially reserve for each hash table bucket.  */
 108 #define DEFAULT_DATASIZE_PER_BUCKET 1024
 109
 110
 111 /* Global variables.  */
 112 extern struct database_dyn dbs[lastdb];
 113 extern const char *dbnames[lastdb];
 114 extern const char *serv2str[LASTREQ];
 115
 116 extern const struct iovec pwd_iov_disabled;
 117 extern const struct iovec grp_iov_disabled;
 118 extern const struct iovec hst_iov_disabled;
 119
 120
 121 /* Initial number of threads to run.  */
 122 extern int nthreads;
 123 /* Maximum number of threads to use.  */
 124 extern int max_nthreads;
 125
 126 /* User name to run server processes as.  */
 127 extern const char *server_user;
 128
 129 /* Name and UID of user who is allowed to request statistics.  */
 130 extern const char *stat_user;
 131 extern uid_t stat_uid;
 132
 133 /* Time the server was started.  */
 134 extern time_t start_time;
 135
 136 /* Number of times clients had to wait.  */
 137 extern unsigned long int client_queued;
 138
 139 /* Maximum needed alignment.  */
 140 extern const size_t block_align;
 141
 142 /* Number of times a value is reloaded without being used.  UINT_MAX
 143    means unlimited.  */
 144 extern unsigned int reload_count;
 145
 146 /* Pagesize minus one.  */
 147 extern uintptr_t pagesize_m1;
 148
 149 /* Nonzero if paranoia mode is enabled.  */
 150 extern int paranoia;
 151 /* Time after which the process restarts.  */
 152 extern time_t restart_time;
 153 /* How much time between restarts.  */
 154 extern time_t restart_interval;
 155 /* Old current working directory.  */
 156 extern const char *oldcwd;
 157 /* Old user and group ID.  */
 158 extern uid_t old_uid;
 159 extern gid_t old_gid;
 160
 161
 162 /* Prototypes for global functions.  */
 163
 164 /* nscd.c */
 165 extern void termination_handler (int signum) __attribute__ ((__noreturn__));
 166 extern int nscd_open_socket (void);
 167
 168 /* connections.c */
 169 extern void nscd_init (void);
 170 extern void close_sockets (void);
 171 extern void start_threads (void) __attribute__ ((__noreturn__));
 172
 173 /* nscd_conf.c */
 174 extern int nscd_parse_file (const char *fname,
 175                             struct database_dyn dbs[lastdb]);
 176
 177 /* nscd_stat.c */
 178 extern void send_stats (int fd, struct database_dyn dbs[lastdb]);
 179 extern int receive_print_stats (void) __attribute__ ((__noreturn__));
 180
 181 /* cache.c */
 182 extern struct datahead *cache_search (request_type, void *key, size_t len,
 183                                       struct database_dyn *table,
 184                                       uid_t owner);
 185 extern int cache_add (int type, const void *key, size_t len,
 186                       struct datahead *packet, bool first,
 187                       struct database_dyn *table, uid_t owner);
 188 extern void prune_cache (struct database_dyn *table, time_t now, int fd);
 189
 190 /* pwdcache.c */
 191 extern void addpwbyname (struct database_dyn *db, int fd, request_header *req,
 192                          void *key, uid_t uid);
 193 extern void addpwbyuid (struct database_dyn *db, int fd, request_header *req,
 194                         void *key, uid_t uid);
 195 extern void readdpwbyname (struct database_dyn *db, struct hashentry *he,
 196                            struct datahead *dh);
 197 extern void readdpwbyuid (struct database_dyn *db, struct hashentry *he,
 198                           struct datahead *dh);
 199
 200 /* grpcache.c */
 201 extern void addgrbyname (struct database_dyn *db, int fd, request_header *req,
 202                          void *key, uid_t uid);
 203 extern void addgrbygid (struct database_dyn *db, int fd, request_header *req,
 204                         void *key, uid_t uid);
 205 extern void readdgrbyname (struct database_dyn *db, struct hashentry *he,
 206                            struct datahead *dh);
 207 extern void readdgrbygid (struct database_dyn *db, struct hashentry *he,
 208                           struct datahead *dh);
 209
 210 /* hstcache.c */
 211 extern void addhstbyname (struct database_dyn *db, int fd, request_header *req,
 212                           void *key, uid_t uid);
 213 extern void addhstbyaddr (struct database_dyn *db, int fd, request_header *req,
 214                           void *key, uid_t uid);
 215 extern void addhstbynamev6 (struct database_dyn *db, int fd,
 216                             request_header *req, void *key, uid_t uid);
 217 extern void addhstbyaddrv6 (struct database_dyn *db, int fd,
 218                             request_header *req, void *key, uid_t uid);
 219 extern void readdhstbyname (struct database_dyn *db, struct hashentry *he,
 220                             struct datahead *dh);
 221 extern void readdhstbyaddr (struct database_dyn *db, struct hashentry *he,
 222                             struct datahead *dh);
 223 extern void readdhstbynamev6 (struct database_dyn *db, struct hashentry *he,
 224                               struct datahead *dh);
 225 extern void readdhstbyaddrv6 (struct database_dyn *db, struct hashentry *he,
 226                               struct datahead *dh);
 227
 228 /* aicache.c */
 229 extern void addhstai (struct database_dyn *db, int fd, request_header *req,
 230                       void *key, uid_t uid);
 231 extern void readdhstai (struct database_dyn *db, struct hashentry *he,
 232                         struct datahead *dh);
 233
 234
 235 /* initgrcache.c */
 236 extern void addinitgroups (struct database_dyn *db, int fd,
 237                            request_header *req, void *key, uid_t uid);
 238 extern void readdinitgroups (struct database_dyn *db, struct hashentry *he,
 239                              struct datahead *dh);
 240
 241 /* mem.c */
 242 extern void *mempool_alloc (struct database_dyn *db, size_t len);
 243 extern void gc (struct database_dyn *db);
 244
 245
 246 /* nscd_setup_thread.c */
 247 extern void setup_thread (struct database_dyn *db);
 248
 249
 250 /* Special version of TEMP_FAILURE_RETRY for functions returning error
 251    values.  */
 252 #define TEMP_FAILURE_RETRY_VAL(expression) \
 253   (__extension__                                                              \
 254     ({ long int __result;                                                     \
 255        do __result = (long int) (expression);                                 \
 256        while (__result == EINTR);                                             \
 257        __result; }))
 258
 259 #endif /* nscd.h */