From 863e9ca2c640ce7a94acf81cff7408edc6f64e01 Mon Sep 17 00:00:00 2001 From: Andrew Bartlett Date: Sat, 4 Jan 2003 08:48:15 +0000 Subject: Merge from HEAD - mimir's new gencache based namecache code. Andrew Bartlett (This used to be commit f79324f730c400342f445c931b0d75ff756d7cc7) --- source3/libsmb/namecache.c | 323 +++++++++++++++++++++------------------------ 1 file changed, 153 insertions(+), 170 deletions(-) (limited to 'source3/libsmb/namecache.c') diff --git a/source3/libsmb/namecache.c b/source3/libsmb/namecache.c index 724e0237d2..40777011a1 100644 --- a/source3/libsmb/namecache.c +++ b/source3/libsmb/namecache.c @@ -1,9 +1,10 @@ /* Unix SMB/CIFS implementation. - NetBIOS name cache module. - - Copyright (C) Tim Potter, 2002 + NetBIOS name cache module on top of gencache mechanism. + + Copyright (C) Tim Potter 2002 + Copyright (C) Rafal Szczesniak 2002 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -22,242 +23,224 @@ #include "includes.h" -static BOOL done_namecache_init; -static BOOL enable_namecache; -static TDB_CONTEXT *namecache_tdb; +#define NBTKEY_FMT "NBT/%s#%02X" -struct nc_value { - time_t expiry; /* When entry expires */ - int count; /* Number of addresses */ - struct in_addr ip_list[1]; /* Address list */ -}; -/* Initialise namecache system */ +/** + * Initialise namecache system. Function calls gencache + * initialisation function to perform necessary actions + * + * @return true upon successful initialisation of the cache or + * false on failure + **/ BOOL namecache_enable(void) { - /* Check if we have been here before, or name caching disabled - by setting the name cache timeout to zero. */ - - if (done_namecache_init) - return False; - - done_namecache_init = True; + /* + * Check if name caching disabled by setting the name cache + * timeout to zero. + */ if (lp_name_cache_timeout() == 0) { - DEBUG(5, ("namecache_init: disabling netbios name cache\n")); + DEBUG(5, ("namecache_enable: disabling netbios name cache\n")); return False; } - /* Open namecache tdb in read/write or readonly mode */ + /* Init namecache by calling gencache initialisation */ - namecache_tdb = tdb_open_log( - lock_path("namecache.tdb"), 0, - TDB_DEFAULT, O_RDWR | O_CREAT, 0644); - - if (!namecache_tdb) { - DEBUG(5, ("namecache_init: could not open %s\n", - lock_path("namecache.tdb"))); + if (!gencache_init()) { + DEBUG(2, ("namecache_enable: Couldn't initialise namecache on top of gencache.\n")); return False; } - DEBUG(5, ("namecache_init: enabling netbios namecache, timeout %d " + /* I leave it for now, though I don't think we really need this (mimir, 27.09.2002) */ + DEBUG(5, ("namecache_enable: enabling netbios namecache, timeout %d " "seconds\n", lp_name_cache_timeout())); - enable_namecache = True; - return True; } -/* Return a key for a name and name type. The caller must free - retval.dptr when finished. */ -static TDB_DATA namecache_key(const char *name, int name_type) +/** + * Shutdown namecache. Routine calls gencache close function + * to safely close gencache file. + * + * @return true upon successful shutdown of the cache or + * false on failure + **/ + +BOOL namecache_shutdown(void) { - TDB_DATA retval; - char *keystr; - - asprintf(&keystr, "%s#%02X", strupper_static(name), name_type); - - retval.dsize = strlen(keystr) + 1; - retval.dptr = keystr; - - return retval; + if (!gencache_shutdown()) { + DEBUG(2, ("namecache_shutdown: Couldn't close namecache on top of gencache.\n")); + return False; + } + + DEBUG(5, ("namecache_shutdown: netbios namecache closed successfully.\n")); + return True; } -/* Return a data value for an IP list. The caller must free - retval.dptr when finished. */ - -static TDB_DATA namecache_value(struct in_addr *ip_list, int num_names, - time_t expiry) -{ - TDB_DATA retval; - struct nc_value *value; - int size = sizeof(struct nc_value); - if (num_names > 0) - size += sizeof(struct in_addr) * (num_names-1); +/** + * Generates a key for netbios name lookups on basis of + * netbios name and type. + * The caller must free returned key string when finished. + * + * @param name netbios name string (case insensitive) + * @param name_type netbios type of the name being looked up + * + * @return string consisted of uppercased name and appended + * type number + */ - value = (struct nc_value *)malloc(size); - - memset(value, 0, size); - - value->expiry = expiry; - value->count = num_names; - - if (ip_list) - memcpy(value->ip_list, ip_list, sizeof(struct in_addr) * num_names); - - retval.dptr = (char *)value; - retval.dsize = size; +static char* namecache_key(const char *name, int name_type) +{ + char *keystr; + asprintf(&keystr, NBTKEY_FMT, strupper_static(name), name_type); - return retval; + return keystr; } -/* Store a name in the name cache */ -void namecache_store(const char *name, int name_type, - int num_names, struct in_addr *ip_list) +/** + * Store a name(s) in the name cache + * + * @param name netbios names array + * @param name_type integer netbios name type + * @param num_names number of names being stored + * @param ip_list array of in_addr structures containing + * ip addresses being stored + **/ + +BOOL namecache_store(const char *name, int name_type, + int num_names, struct in_addr *ip_list) { - TDB_DATA key, value; time_t expiry; + char *key, *value_string; int i; - if (!enable_namecache) - return; + /* + * we use gecache call to avoid annoying debug messages about + * initialised namecache again and again... + */ + if (!gencache_init()) return False; DEBUG(5, ("namecache_store: storing %d address%s for %s#%02x: ", - num_names, num_names == 1 ? "": "es", name, name_type)); + num_names, num_names == 1 ? "": "es", name, name_type)); for (i = 0; i < num_names; i++) DEBUGADD(5, ("%s%s", inet_ntoa(ip_list[i]), - i == (num_names - 1) ? "" : ", ")); + i == (num_names - 1) ? "" : ", ")); DEBUGADD(5, ("\n")); key = namecache_key(name, name_type); - /* Cache pdc location or dc lists for only a little while - otherwise if we lock on to a bad DC we can potentially be - out of action for the entire cache timeout time! */ + /* + * Cache pdc location or dc lists for only a little while + * otherwise if we lock on to a bad DC we can potentially be + * out of action for the entire cache timeout time! + */ - if (name_type != 0x1b || name_type != 0x1c) + if (name_type == 0x1b || name_type == 0x1c) expiry = time(NULL) + 10; else expiry = time(NULL) + lp_name_cache_timeout(); - value = namecache_value(ip_list, num_names, expiry); - - tdb_store(namecache_tdb, key, value, TDB_REPLACE); - - free(key.dptr); - free(value.dptr); + /* + * Generate string representation of ip addresses list + * First, store the number of ip addresses and then + * place each single ip + */ + ipstr_list_make(&value_string, ip_list, num_names); + + /* set the entry */ + return (gencache_set(key, value_string, expiry)); } -/* Look up a name in the name cache. Return a mallocated list of IP - addresses if the name is contained in the cache. */ + +/** + * Look up a name in the cache. + * + * @param name netbios name to look up for + * @param name_type netbios name type of @param name + * @param ip_list mallocated list of IP addresses if found in the cache, + * NULL otherwise + * @param num_names number of entries found + * + * @return true upon successful fetch or + * false if name isn't found in the cache or has expired + **/ BOOL namecache_fetch(const char *name, int name_type, struct in_addr **ip_list, - int *num_names) + int *num_names) { - TDB_DATA key, value; - struct nc_value *data = NULL; - time_t now; - int i; + char *key, *value; + time_t timeout; - *ip_list = NULL; *num_names = 0; - if (!enable_namecache) - return False; + /* exit now if null pointers were passed as they're required further */ + if (!ip_list || !num_names) return False; - /* Read value */ + if (!gencache_init()) + return False; + /* + * Use gencache interface - lookup the key + */ key = namecache_key(name, name_type); - value = tdb_fetch(namecache_tdb, key); - - if (!value.dptr) { - DEBUG(5, ("namecache_fetch: %s#%02x not found\n", - name, name_type)); - goto done; - } - - data = (struct nc_value *)value.dptr; - - /* Check expiry time */ - - now = time(NULL); - - if (now > data->expiry) { - - DEBUG(5, ("namecache_fetch: entry for %s#%02x expired\n", - name, name_type)); - - tdb_delete(namecache_tdb, key); - - value = tdb_null; - - goto done; - } - - if ((data->expiry - now) > lp_name_cache_timeout()) { - - /* Someone may have changed the system time on us */ - - DEBUG(5, ("namecache_fetch: entry for %s#%02x has bad expiry\n", - name, name_type)); - - tdb_delete(namecache_tdb, key); - - value = tdb_null; - - goto done; - } - - /* Extract and return namelist */ - - DEBUG(5, ("namecache_fetch: returning %d address%s for %s#%02x: ", - data->count, data->count == 1 ? "" : "es", name, name_type)); - - if (data->count) { - - *ip_list = (struct in_addr *)malloc( - sizeof(struct in_addr) * data->count); - - memcpy(*ip_list, data->ip_list, sizeof(struct in_addr) * data->count); - - *num_names = data->count; - - for (i = 0; i < *num_names; i++) - DEBUGADD(5, ("%s%s", inet_ntoa((*ip_list)[i]), - i == (*num_names - 1) ? "" : ", ")); - + if (!gencache_get(key, &value, &timeout)) { + DEBUG(5, ("no entry for %s#%02X found.\n", name, name_type)); + SAFE_FREE(key); + return False; + } else { + DEBUG(5, ("name %s#%02X found.\n", name, name_type)); } + + /* + * Split up the stored value into the list of IP adresses + */ + *num_names = ipstr_list_parse(value, ip_list); + + SAFE_FREE(key); + SAFE_FREE(value); + return *num_names > 0; /* true only if some ip has been fetched */ +} - DEBUGADD(5, ("\n")); -done: - SAFE_FREE(key.dptr); - SAFE_FREE(data); +/** + * Delete single namecache entry. Look at the + * gencache_iterate definition. + * + **/ - return value.dsize > 0; +static void flush_netbios_name(const char* key, const char *value, time_t timeout, void* dptr) +{ + gencache_del(key); + DEBUG(5, ("Deleting entry %s\n", key)); } -/* Flush all names from the name cache */ + +/** + * Flush all names from the name cache. + * It's done by gencache_iterate() + * + * @return True upon successful deletion or + * False in case of an error + **/ void namecache_flush(void) { - int result; - - if (!namecache_tdb) + if (!gencache_init()) return; - result = tdb_traverse(namecache_tdb, tdb_traverse_delete_fn, NULL); - - if (result == -1) - DEBUG(5, ("namecache_flush: error deleting cache entries\n")); - else - DEBUG(5, ("namecache_flush: deleted %d cache entr%s\n", - result, result == 1 ? "y" : "ies")); + /* + * iterate through each NBT cache's entry and flush it + * by flush_netbios_name function + */ + gencache_iterate(flush_netbios_name, NULL, "NBT/*"); + DEBUG(5, ("Namecache flushed\n")); } + -- cgit