Having waited for *way* too long, this is mimir's namecache and trusted domain

cache code.

This uses gencache, mimir's new caching code that stores at text-based cache
of various data.

Mimir has done a *lot* of work on this patch, and it is finally time to
get it in CVS.

Andrew Bartlett
(This used to be commit 47f3bfe9564e7f3aff60cefaefd599e0abb30a31)

1 files changed, 215 insertions, 0 deletions

diff --git a/source3/libsmb/trustdom_cache.c b/source3/libsmb/trustdom_cache.c
new file mode 100644
index 0000000000..cddbb2daa6
--- /dev/null
+++ b/source3/libsmb/trustdom_cache.c
@@ -0,0 +1,215 @@
+/* 
+   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"
+
+
+/**
+ * @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;
+	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;
+
+	/*
+	 * 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) {
+		return (gencache_set(alt_key, sid_string, timeout)
+		        && gencache_set(key, sid_string, timeout));
+	}
+		 
+	return gencache_set(key, sid_string, timeout);
+}
+
+
+/**
+ * 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, *value;
+	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 (!gencache_get(key, &value, &timeout)) {
+		DEBUG(5, ("no entry for trusted domain %s found.\n", name));
+		return False;
+	} else {
+		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;
+		return False;
+	}
+	
+	return True;
+}
+
+
+/**
+ * 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"));
+}
+