1: /* Copyright (c) 1998, 1999, 2000, 2003, 2004, 2005, 2006, 2007
    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: /* This file defines everything that client code should need to
   22:    know to talk to the nscd daemon.  */
   23: 
   24: #ifndef _NSCD_CLIENT_H
   25: #define _NSCD_CLIENT_H  1
   26: 
   27: #include <stdbool.h>
   28: #include <stdint.h>
   29: #include <sys/types.h>
   30: #include <atomic.h>
   31: #include <nscd-types.h>
   32: #include <sys/uio.h>
   33: 
   34: 
   35: /* Version number of the daemon interface */
   36: #define NSCD_VERSION 2
   37: 
   38: /* Path of the file where the PID of the running system is stored.  */
   39: #define _PATH_NSCDPID    "/var/run/nscd/nscd.pid"
   40: 
   41: /* Path for the Unix domain socket.  */
   42: #define _PATH_NSCDSOCKET "/var/run/nscd/socket"
   43: 
   44: /* Path for the configuration file.  */
   45: #define _PATH_NSCDCONF   "/etc/nscd.conf"
   46: 
   47: /* Maximu allowed length for the key.  */
   48: #define MAXKEYLEN 1024
   49: 
   50: 
   51: /* Available services.  */
   52: typedef enum
   53: {
   54:   GETPWBYNAME,
   55:   GETPWBYUID,
   56:   GETGRBYNAME,
   57:   GETGRBYGID,
   58:   GETHOSTBYNAME,
   59:   GETHOSTBYNAMEv6,
   60:   GETHOSTBYADDR,
   61:   GETHOSTBYADDRv6,
   62:   SHUTDOWN,             /* Shut the server down.  */
   63:   GETSTAT,              /* Get the server statistic.  */
   64:   INVALIDATE,           /* Invalidate one special cache.  */
   65:   GETFDPW,
   66:   GETFDGR,
   67:   GETFDHST,
   68:   GETAI,
   69:   INITGROUPS,
   70:   GETSERVBYNAME,
   71:   GETSERVBYPORT,
   72:   GETFDSERV,
   73:   LASTREQ
   74: } request_type;
   75: 
   76: 
   77: /* Header common to all requests */
   78: typedef struct
   79: {
   80:   int32_t version;      /* Version number of the daemon interface.  */
   81:   request_type type;    /* Service requested.  */
   82:   int32_t key_len;      /* Key length.  */
   83: } request_header;
   84: 
   85: 
   86: /* Structure sent in reply to password query.  Note that this struct is
   87:    sent also if the service is disabled or there is no record found.  */
   88: typedef struct
   89: {
   90:   int32_t version;
   91:   int32_t found;
   92:   nscd_ssize_t pw_name_len;
   93:   nscd_ssize_t pw_passwd_len;
   94:   uid_t pw_uid;
   95:   gid_t pw_gid;
   96:   nscd_ssize_t pw_gecos_len;
   97:   nscd_ssize_t pw_dir_len;
   98:   nscd_ssize_t pw_shell_len;
   99: } pw_response_header;
  100: 
  101: 
  102: /* Structure sent in reply to group query.  Note that this struct is
  103:    sent also if the service is disabled or there is no record found.  */
  104: typedef struct
  105: {
  106:   int32_t version;
  107:   int32_t found;
  108:   nscd_ssize_t gr_name_len;
  109:   nscd_ssize_t gr_passwd_len;
  110:   gid_t gr_gid;
  111:   nscd_ssize_t gr_mem_cnt;
  112: } gr_response_header;
  113: 
  114: 
  115: /* Structure sent in reply to host query.  Note that this struct is
  116:    sent also if the service is disabled or there is no record found.  */
  117: typedef struct
  118: {
  119:   int32_t version;
  120:   int32_t found;
  121:   nscd_ssize_t h_name_len;
  122:   nscd_ssize_t h_aliases_cnt;
  123:   int32_t h_addrtype;
  124:   int32_t h_length;
  125:   nscd_ssize_t h_addr_list_cnt;
  126:   int32_t error;
  127: } hst_response_header;
  128: 
  129: 
  130: /* Structure sent in reply to addrinfo query.  Note that this struct is
  131:    sent also if the service is disabled or there is no record found.  */
  132: typedef struct
  133: {
  134:   int32_t version;
  135:   int32_t found;
  136:   nscd_ssize_t naddrs;
  137:   nscd_ssize_t addrslen;
  138:   nscd_ssize_t canonlen;
  139:   int32_t error;
  140: } ai_response_header;
  141: 
  142: /* Structure filled in by __nscd_getai.  */
  143: struct nscd_ai_result
  144: {
  145:   int naddrs;
  146:   char *canon;
  147:   uint8_t *family;
  148:   char *addrs;
  149: };
  150: 
  151: /* Structure sent in reply to initgroups query.  Note that this struct is
  152:    sent also if the service is disabled or there is no record found.  */
  153: typedef struct
  154: {
  155:   int32_t version;
  156:   int32_t found;
  157:   nscd_ssize_t ngrps;
  158: } initgr_response_header;
  159: 
  160: 
  161: /* Structure sent in reply to services query.  Note that this struct is
  162:    sent also if the service is disabled or there is no record found.  */
  163: typedef struct
  164: {
  165:   int32_t version;
  166:   int32_t found;
  167:   nscd_ssize_t s_name_len;
  168:   nscd_ssize_t s_proto_len;
  169:   nscd_ssize_t s_aliases_cnt;
  170:   int32_t s_port;
  171: } serv_response_header;
  172: 
  173: 
  174: /* Type for offsets in data part of database.  */
  175: typedef uint32_t ref_t;
  176: /* Value for invalid/no reference.  */
  177: #define ENDREF  UINT32_MAX
  178: 
  179: /* Timestamp type.  */
  180: typedef uint64_t nscd_time_t;
  181: 
  182: /* Alignment requirement of the beginning of the data region.  */
  183: #define ALIGN 16
  184: 
  185: 
  186: /* Head of record in data part of database.  */
  187: struct datahead
  188: {
  189:   nscd_ssize_t allocsize;       /* Allocated Bytes.  */
  190:   nscd_ssize_t recsize;         /* Size of the record.  */
  191:   nscd_time_t timeout;          /* Time when this entry becomes invalid.  */
  192:   uint8_t notfound;             /* Nonzero if data has not been found.  */
  193:   uint8_t nreloads;             /* Reloads without use.  */
  194:   uint8_t usable;               /* False if the entry must be ignored.  */
  195:   uint64_t :40;                 /* Alignment.  */
  196: 
  197:   /* We need to have the following element aligned for the response
  198:      header data types and their use in the 'struct dataset' types
  199:      defined in the XXXcache.c files.  */
  200:   union
  201:   {
  202:     pw_response_header pwdata;
  203:     gr_response_header grdata;
  204:     hst_response_header hstdata;
  205:     ai_response_header aidata;
  206:     initgr_response_header initgrdata;
  207:     serv_response_header servdata;
  208:     nscd_ssize_t align1;
  209:     nscd_time_t align2;
  210:   } data[0];
  211: };
  212: 
  213: 
  214: /* Structure for one hash table entry.  */
  215: struct hashentry
  216: {
  217:   request_type type:8;          /* Which type of dataset.  */
  218:   bool first;                   /* True if this was the original key.  */
  219:   nscd_ssize_t len;             /* Length of key.  */
  220:   ref_t key;                    /* Pointer to key.  */
  221:   int32_t owner;                /* If secure table, this is the owner.  */
  222:   ref_t next;                   /* Next entry in this hash bucket list.  */
  223:   ref_t packet;                 /* Records for the result.  */
  224:   union
  225:   {
  226:     struct hashentry *dellist;  /* Next record to be deleted.  This can be a
  227:                                    pointer since only nscd uses this field.  */
  228:     ref_t *prevp;               /* Pointer to field containing forward
  229:                                    reference.  */
  230:   };
  231: };
  232: 
  233: 
  234: /* Current persistent database version.  */
  235: #define DB_VERSION      1
  236: 
  237: /* Maximum time allowed between updates of the timestamp.  */
  238: #define MAPPING_TIMEOUT (5 * 60)
  239: 
  240: 
  241: /* Header of persistent database file.  */
  242: struct database_pers_head
  243: {
  244:   int32_t version;
  245:   int32_t header_size;
  246:   volatile int32_t gc_cycle;
  247:   volatile int32_t nscd_certainly_running;
  248:   volatile nscd_time_t timestamp;
  249: 
  250:   nscd_ssize_t module;
  251:   nscd_ssize_t data_size;
  252: 
  253:   nscd_ssize_t first_free;      /* Offset of first free byte in data area.  */
  254: 
  255:   nscd_ssize_t nentries;
  256:   nscd_ssize_t maxnentries;
  257:   nscd_ssize_t maxnsearched;
  258: 
  259:   uint64_t poshit;
  260:   uint64_t neghit;
  261:   uint64_t posmiss;
  262:   uint64_t negmiss;
  263: 
  264:   uint64_t rdlockdelayed;
  265:   uint64_t wrlockdelayed;
  266: 
  267:   uint64_t addfailed;
  268: 
  269:   ref_t array[0];
  270: };
  271: 
  272: 
  273: /* Mapped database record.  */
  274: struct mapped_database
  275: {
  276:   const struct database_pers_head *head;
  277:   const char *data;
  278:   size_t mapsize;
  279:   int counter;          /* > 0 indicates it is usable.  */
  280:   size_t datasize;
  281: };
  282: #define NO_MAPPING ((struct mapped_database *) -1l)
  283: 
  284: struct locked_map_ptr
  285: {
  286:   int lock;
  287:   struct mapped_database *mapped;
  288: };
  289: #define libc_locked_map_ptr(class, name) class struct locked_map_ptr name
  290: 
  291: 
  292: /* Open socket connection to nscd server.  */
  293: extern int __nscd_open_socket (const char *key, size_t keylen,
  294:                                request_type type, void *response,
  295:                                size_t responselen) attribute_hidden;
  296: 
  297: /* Get reference of mapping.  */
  298: extern struct mapped_database *__nscd_get_map_ref (request_type type,
  299:                                                    const char *name,
  300:                                                    volatile struct locked_map_ptr *mapptr,
  301:                                                    int *gc_cyclep);
  302: 
  303: /* Unmap database.  */
  304: extern void __nscd_unmap (struct mapped_database *mapped);
  305: 
  306: /* Drop reference of mapping.  */
  307: static inline int __nscd_drop_map_ref (struct mapped_database *map,
  308:                                        int *gc_cycle)
  309: {
  310:   if (map != NO_MAPPING)
  311:     {
  312:       int now_cycle = map->head->gc_cycle;
  313:       if (__builtin_expect (now_cycle != *gc_cycle, 0))
  314:         {
  315:           /* We might have read inconsistent data.  */
  316:           *gc_cycle = now_cycle;
  317:           return -1;
  318:         }
  319: 
  320:       if (atomic_decrement_val (&map->counter) == 0)
  321:         __nscd_unmap (map);
  322:     }
  323: 
  324:   return 0;
  325: }
  326: 
  327: 
  328: /* Search the mapped database.  */
  329: extern struct datahead *__nscd_cache_search (request_type type,
  330:                                              const char *key,
  331:                                              size_t keylen,
  332:                                              const struct mapped_database *mapped);
  333: 
  334: /* Wrappers around read, readv and write that only read/write less than LEN
  335:    bytes on error or EOF.  */
  336: extern ssize_t __readall (int fd, void *buf, size_t len)
  337:   attribute_hidden;
  338: extern ssize_t __readvall (int fd, const struct iovec *iov, int iovcnt)
  339:   attribute_hidden;
  340: extern ssize_t writeall (int fd, const void *buf, size_t len)
  341:   attribute_hidden;
  342: extern ssize_t sendfileall (int tofd, int fromfd, off_t off, size_t len)
  343:   attribute_hidden;
  344: 
  345: #endif /* nscd.h */