1 files changed, 394 insertions, 0 deletions
diff --git a/source3/libsmb/namecache.c b/source3/libsmb/namecache.c
new file mode 100644
index 0000000000..ba706e5ee2
--- /dev/null
+++ b/source3/libsmb/namecache.c
@@ -0,0 +1,394 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   NetBIOS name cache module on top of gencache mechanism.
+
+   Copyright (C) Tim Potter         2002
+   Copyright (C) Rafal Szczesniak   2002
+   Copyright (C) Jeremy Allison     2007
+
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+
+#define NBTKEY_FMT  "NBT/%s#%02X"
+
+/**
+ * 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 name caching disabled by setting the name cache
+	 * timeout to zero.
+	 */
+
+	if (lp_name_cache_timeout() == 0) {
+		DEBUG(5, ("namecache_enable: disabling netbios name cache\n"));
+		return False;
+	}
+
+	/* Init namecache by calling gencache initialisation */
+
+	if (!gencache_init()) {
+		DEBUG(2, ("namecache_enable: "
+			"Couldn't initialise namecache on top of gencache.\n"));
+		return False;
+	}
+
+	/* 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()));
+
+	return True;
+}
+
+/**
+ * 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)
+{
+	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;
+}
+
+/**
+ * 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
+ */
+
+static char* namecache_key(const char *name,
+				int name_type)
+{
+	char *keystr;
+	asprintf_strupper_m(&keystr, NBTKEY_FMT, name, name_type);
+
+	return keystr;
+}
+
+/**
+ * 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 ip_service *ip_list)
+{
+	time_t expiry;
+	char *key, *value_string;
+	int i;
+	bool ret;
+
+	/*
+	 * we use gecache call to avoid annoying debug messages about
+	 * initialised namecache again and again...
+	 */
+	if (!gencache_init()) {
+		return False;
+	}
+
+	if (name_type > 255) {
+		return False; /* Don't store non-real name types. */
+	}
+
+	if ( DEBUGLEVEL >= 5 ) {
+		TALLOC_CTX *ctx = talloc_stackframe();
+		char *addr = NULL;
+
+		DEBUG(5, ("namecache_store: storing %d address%s for %s#%02x: ",
+			num_names, num_names == 1 ? "": "es", name, name_type));
+
+		for (i = 0; i < num_names; i++) {
+			addr = print_canonical_sockaddr(ctx,
+							&ip_list[i].ss);
+			if (!addr) {
+				continue;
+			}
+			DEBUGADD(5, ("%s%s", addr,
+				(i == (num_names - 1) ? "" : ",")));
+
+		}
+		DEBUGADD(5, ("\n"));
+		TALLOC_FREE(ctx);
+	}
+
+	key = namecache_key(name, name_type);
+	if (!key) {
+		return False;
+	}
+
+	expiry = time(NULL) + lp_name_cache_timeout();
+
+	/*
+	 * Generate string representation of ip addresses list
+	 * First, store the number of ip addresses and then
+	 * place each single ip
+	 */
+	if (!ipstr_list_make(&value_string, ip_list, num_names)) {
+		SAFE_FREE(key);
+		SAFE_FREE(value_string);
+		return false;
+	}
+
+	/* set the entry */
+	ret = gencache_set(key, value_string, expiry);
+	SAFE_FREE(key);
+	SAFE_FREE(value_string);
+	return ret;
+}
+
+/**
+ * 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 ip_service **ip_list,
+			int *num_names)
+{
+	char *key, *value;
+	time_t timeout;
+
+	/* exit now if null pointers were passed as they're required further */
+	if (!ip_list || !num_names) {
+		return False;
+	}
+
+	if (!gencache_init()) {
+		return False;
+	}
+
+	if (name_type > 255) {
+		return False; /* Don't fetch non-real name types. */
+	}
+
+	*num_names = 0;
+
+	/*
+	 * Use gencache interface - lookup the key
+	 */
+	key = namecache_key(name, name_type);
+	if (!key) {
+		return False;
+	}
+
+	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 */
+}
+
+/**
+ * Remove a namecache entry. Needed for site support.
+ *
+ **/
+
+bool namecache_delete(const char *name, int name_type)
+{
+	bool ret;
+	char *key;
+
+	if (!gencache_init())
+		return False;
+
+	if (name_type > 255) {
+		return False; /* Don't fetch non-real name types. */
+	}
+
+	key = namecache_key(name, name_type);
+	if (!key) {
+		return False;
+	}
+	ret = gencache_del(key);
+	SAFE_FREE(key);
+	return ret;
+}
+
+/**
+ * Delete single namecache entry. Look at the
+ * gencache_iterate definition.
+ *
+ **/
+
+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.
+ * It's done by gencache_iterate()
+ *
+ * @return true upon successful deletion or
+ *         false in case of an error
+ **/
+
+void namecache_flush(void)
+{
+	if (!gencache_init()) {
+		return;
+	}
+
+	/*
+	 * 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"));
+}
+
+/* Construct a name status record key. */
+
+static char *namecache_status_record_key(const char *name,
+				int name_type1,
+				int name_type2,
+				const struct sockaddr_storage *keyip)
+{
+	char addr[INET6_ADDRSTRLEN];
+	char *keystr;
+
+	print_sockaddr(addr, sizeof(addr), keyip);
+	asprintf_strupper_m(&keystr, "NBT/%s#%02X.%02X.%s", name,
+			    name_type1, name_type2, addr);
+	return keystr;
+}
+
+/* Store a name status record. */
+
+bool namecache_status_store(const char *keyname, int keyname_type,
+		int name_type, const struct sockaddr_storage *keyip,
+		const char *srvname)
+{
+	char *key;
+	time_t expiry;
+	bool ret;
+
+	if (!gencache_init()) {
+		return False;
+	}
+
+	key = namecache_status_record_key(keyname, keyname_type,
+			name_type, keyip);
+	if (!key)
+		return False;
+
+	expiry = time(NULL) + lp_name_cache_timeout();
+	ret = gencache_set(key, srvname, expiry);
+
+	if (ret) {
+		DEBUG(5, ("namecache_status_store: entry %s -> %s\n",
+					key, srvname ));
+	} else {
+		DEBUG(5, ("namecache_status_store: entry %s store failed.\n",
+					key ));
+	}
+
+	SAFE_FREE(key);
+	return ret;
+}
+
+/* Fetch a name status record. */
+
+bool namecache_status_fetch(const char *keyname,
+				int keyname_type,
+				int name_type,
+				const struct sockaddr_storage *keyip,
+				char *srvname_out)
+{
+	char *key = NULL;
+	char *value = NULL;
+	time_t timeout;
+
+	if (!gencache_init())
+		return False;
+
+	key = namecache_status_record_key(keyname, keyname_type,
+			name_type, keyip);
+	if (!key)
+		return False;
+
+	if (!gencache_get(key, &value, &timeout)) {
+		DEBUG(5, ("namecache_status_fetch: no entry for %s found.\n",
+					key));
+		SAFE_FREE(key);
+		return False;
+	} else {
+		DEBUG(5, ("namecache_status_fetch: key %s -> %s\n",
+					key, value ));
+	}
+
+	strlcpy(srvname_out, value, 16);
+	SAFE_FREE(key);
+	SAFE_FREE(value);
+	return True;
+}