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