--- /dev/null
+/*
+ Unix SMB/CIFS implementation.
+
+ Trusted domain names cache on top of gencache.
+
+ 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
+ the Free Software Foundation; either version 2 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "includes.h"
+
+#undef DBGC_CLASS
+#define DBGC_CLASS DBGC_ALL /* there's no proper class yet */
+
+#define TDOMKEY_FMT "TDOM/%s"
+#define TDOMTSKEY "TDOMCACHE/TIMESTAMP"
+
+
+/**
+ * @file trustdom_cache.c
+ *
+ * Implementation of trusted domain names cache useful when
+ * samba acts as domain member server. In such case, caching
+ * domain names currently trusted gives a performance gain
+ * because there's no need to query PDC each time we need
+ * list of trusted domains
+ **/
+
+
+/**
+ * Initialise trustdom name caching system. Call gencache
+ * initialisation routine to perform necessary activities.
+ *
+ * @return true upon successful cache initialisation or
+ * false if cache init failed
+ **/
+
+BOOL trustdom_cache_enable(void)
+{
+ /* Init trustdom cache by calling gencache initialisation */
+ if (!gencache_init()) {
+ DEBUG(2, ("trustdomcache_enable: Couldn't initialise trustdom cache on top of gencache.\n"));
+ return False;
+ }
+
+ return True;
+}
+
+
+/**
+ * Shutdown trustdom name caching system. Calls gencache
+ * shutdown function.
+ *
+ * @return true upon successful cache close or
+ * false if it failed
+ **/
+
+BOOL trustdom_cache_shutdown(void)
+{
+ /* Close trustdom cache by calling gencache shutdown */
+ if (!gencache_shutdown()) {
+ DEBUG(2, ("trustdomcache_shutdown: Couldn't shutdown trustdom cache on top of gencache.\n"));
+ return False;
+ }
+
+ return True;
+}
+
+
+/**
+ * Form up trustdom name key. It is based only
+ * on domain name now.
+ *
+ * @param name trusted domain name
+ * @return cache key for use in gencache mechanism
+ **/
+
+static char* trustdom_cache_key(const char* name)
+{
+ char* keystr = NULL;
+ asprintf(&keystr, TDOMKEY_FMT, strupper_static(name));
+
+ return keystr;
+}
+
+
+/**
+ * Store trusted domain in gencache as the domain name (key)
+ * and ip address of domain controller (value)
+ *
+ * @param name trusted domain name
+ * @param alt_name alternative trusted domain name (used in ADS domains)
+ * @param sid trusted domain's SID
+ * @param timeout cache entry expiration time
+ * @return true upon successful value storing or
+ * false if store attempt failed
+ **/
+
+BOOL trustdom_cache_store(char* name, char* alt_name, const DOM_SID *sid,
+ time_t timeout)
+{
+ char *key, *alt_key;
+ fstring sid_string;
+ BOOL ret;
+
+ /*
+ * we use gecache call to avoid annoying debug messages
+ * about initialised trustdom
+ */
+ if (!gencache_init())
+ return False;
+
+ DEBUG(5, ("trustdom_store: storing SID %s of domain %s\n",
+ sid_string_static(sid), name));
+
+ key = trustdom_cache_key(name);
+ alt_key = alt_name ? trustdom_cache_key(alt_name) : NULL;
+
+ /* Generate string representation domain SID */
+ sid_to_string(sid_string, sid);
+
+ /*
+ * try to put the names in the cache
+ */
+ if (alt_key) {
+ ret = gencache_set(alt_key, sid_string, timeout);
+ if ( ret ) {
+ ret = gencache_set(key, sid_string, timeout);
+ }
+ SAFE_FREE(alt_key);
+ SAFE_FREE(key);
+ return ret;
+ }
+
+ ret = gencache_set(key, sid_string, timeout);
+ SAFE_FREE(key);
+ return ret;
+}
+
+
+/**
+ * Fetch trusted domain's dc from the gencache.
+ * This routine can also be used to check whether given
+ * domain is currently trusted one.
+ *
+ * @param name trusted domain name
+ * @param sid trusted domain's SID to be returned
+ * @return true if entry is found or
+ * false if has expired/doesn't exist
+ **/
+
+BOOL trustdom_cache_fetch(const char* name, DOM_SID* sid)
+{
+ char *key = NULL, *value = NULL;
+ time_t timeout;
+
+ /* init the cache */
+ if (!gencache_init())
+ return False;
+
+ /* exit now if null pointers were passed as they're required further */
+ if (!sid)
+ return False;
+
+ /* prepare a key and get the value */
+ key = trustdom_cache_key(name);
+ if (!key)
+ return False;
+
+ if (!gencache_get(key, &value, &timeout)) {
+ DEBUG(5, ("no entry for trusted domain %s found.\n", name));
+ SAFE_FREE(key);
+ SAFE_FREE(value);
+ return False;
+ } else {
+ SAFE_FREE(key);
+ DEBUG(5, ("trusted domain %s found (%s)\n", name, value));
+ }
+
+ /* convert ip string representation into in_addr structure */
+ if(! string_to_sid(sid, value)) {
+ sid = NULL;
+ SAFE_FREE(value);
+ return False;
+ }
+
+ SAFE_FREE(value);
+ return True;
+}
+
+
+/*******************************************************************
+ fetch the timestamp from the last update
+*******************************************************************/
+
+uint32 trustdom_cache_fetch_timestamp( void )
+{
+ char *value = NULL;
+ time_t timeout;
+ uint32 timestamp;
+
+ /* init the cache */
+ if (!gencache_init())
+ return False;
+
+ if (!gencache_get(TDOMTSKEY, &value, &timeout)) {
+ DEBUG(5, ("no timestamp for trusted domain cache located.\n"));
+ SAFE_FREE(value);
+ return 0;
+ }
+
+ timestamp = atoi(value);
+
+ SAFE_FREE(value);
+ return timestamp;
+}
+
+/*******************************************************************
+ store the timestamp from the last update
+*******************************************************************/
+
+BOOL trustdom_cache_store_timestamp( uint32 t, time_t timeout )
+{
+ fstring value;
+
+ /* init the cache */
+ if (!gencache_init())
+ return False;
+
+ fstr_sprintf(value, "%d", t );
+
+ if (!gencache_set(TDOMTSKEY, value, timeout)) {
+ DEBUG(5, ("failed to set timestamp for trustdom_cache\n"));
+ return False;
+ }
+
+ return True;
+}
+
+
+/*******************************************************************
+ lock the timestamp entry in the trustdom_cache
+*******************************************************************/
+
+BOOL trustdom_cache_lock_timestamp( void )
+{
+ return gencache_lock_entry( TDOMTSKEY ) != -1;
+}
+
+/*******************************************************************
+ unlock the timestamp entry in the trustdom_cache
+*******************************************************************/
+
+void trustdom_cache_unlock_timestamp( void )
+{
+ gencache_unlock_entry( TDOMTSKEY );
+}
+
+/**
+ * Delete single trustdom entry. Look at the
+ * gencache_iterate definition.
+ *
+ **/
+
+static void flush_trustdom_name(const char* key, const char *value, time_t timeout, void* dptr)
+{
+ gencache_del(key);
+ DEBUG(5, ("Deleting entry %s\n", key));
+}
+
+
+/**
+ * Flush all the trusted domains entries from the cache.
+ **/
+
+void trustdom_cache_flush(void)
+{
+ if (!gencache_init())
+ return;
+
+ /*
+ * iterate through each TDOM cache's entry and flush it
+ * by flush_trustdom_name function
+ */
+ gencache_iterate(flush_trustdom_name, NULL, trustdom_cache_key("*"));
+ DEBUG(5, ("Trusted domains cache flushed\n"));
+}
+
+/********************************************************************
+ update the trustdom_cache if needed
+********************************************************************/
+#define TRUSTDOM_UPDATE_INTERVAL 600
+
+void update_trustdom_cache( void )
+{
+ char **domain_names;
+ DOM_SID *dom_sids;
+ uint32 num_domains;
+ uint32 last_check;
+ int time_diff;
+ TALLOC_CTX *mem_ctx = NULL;
+ time_t now = time(NULL);
+ int i;
+
+ /* get the timestamp. We have to initialise it if the last timestamp == 0 */
+
+ if ( (last_check = trustdom_cache_fetch_timestamp()) == 0 )
+ trustdom_cache_store_timestamp(0, now+TRUSTDOM_UPDATE_INTERVAL);
+
+ time_diff = (int) (now - last_check);
+
+ if ( (time_diff > 0) && (time_diff < TRUSTDOM_UPDATE_INTERVAL) ) {
+ DEBUG(10,("update_trustdom_cache: not time to update trustdom_cache yet\n"));
+ return;
+ }
+
+ /* lock the timestamp */
+ if ( !trustdom_cache_lock_timestamp() )
+ return;
+
+ if ( !(mem_ctx = talloc_init("update_trustdom_cache")) ) {
+ DEBUG(0,("update_trustdom_cache: talloc_init() failed!\n"));
+ goto done;
+ }
+
+ /* get the domains and store them */
+
+ if ( enumerate_domain_trusts(mem_ctx, lp_workgroup(), &domain_names,
+ &num_domains, &dom_sids) )
+ {
+ for ( i=0; i<num_domains; i++ ) {
+ trustdom_cache_store( domain_names[i], NULL, &dom_sids[i],
+ now+TRUSTDOM_UPDATE_INTERVAL);
+ }
+
+ trustdom_cache_store_timestamp( now, now+TRUSTDOM_UPDATE_INTERVAL );
+ }
+
+done:
+ /* unlock and we're done */
+ trustdom_cache_unlock_timestamp();
+
+ talloc_destroy( mem_ctx );
+
+ return;
+}
projects / samba / blobdiff