1 files changed, 127 insertions, 0 deletions
diff --git a/src/sync-notrack.c b/src/sync-notrack.c
new file mode 100644
index 0000000..2b5ae38
--- /dev/null
+++ b/src/sync-notrack.c
@@ -0,0 +1,127 @@
+/*
+ * (C) 2006-2007 by Pablo Neira Ayuso <pablo@netfilter.org>
+ * 
+ * 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 "conntrackd.h"
+#include "sync.h"
+#include "network.h"
+#include "us-conntrack.h"
+#include "alarm.h"
+
+static void refresher(struct alarm_list *a, void *data)
+{
+	struct us_conntrack *u = data;
+	char buf[8192];
+	int size;
+
+	if (nfct_get_attr_u32(u->ct, ATTR_STATUS) & IPS_DYING) {
+		
+		debug_ct(u->ct, "persistence destroy");
+
+		size = build_network_msg(NFCT_Q_DESTROY,
+					 STATE(subsys_event),
+					 u->ct,
+					 buf,
+					 sizeof(buf));
+
+		__cache_del(u->cache, u->ct);
+		mcast_send_netmsg(STATE_SYNC(mcast_client), buf);
+	} else {
+		
+		debug_ct(u->ct, "persistence update");
+
+		a->expires = random() % CONFIG(refresh) + 1;
+		size = build_network_msg(NFCT_Q_UPDATE,
+					 STATE(subsys_event),
+					 u->ct,
+					 buf, 
+					 sizeof(buf));
+		mcast_send_netmsg(STATE_SYNC(mcast_client), buf);
+	}
+}
+
+static void cache_notrack_add(struct us_conntrack *u, void *data)
+{
+	struct alarm_list *alarm = data;
+
+	init_alarm(alarm);
+	set_alarm_expiration(alarm, (random() % conf.refresh) + 1);
+	set_alarm_data(alarm, u);
+	set_alarm_function(alarm, refresher);
+	add_alarm(alarm);
+}
+
+static void cache_notrack_update(struct us_conntrack *u, void *data)
+{
+	struct alarm_list *alarm = data;
+	mod_alarm(alarm, (random() % conf.refresh) + 1);
+}
+
+static void cache_notrack_destroy(struct us_conntrack *u, void *data)
+{
+	struct alarm_list *alarm = data;
+	del_alarm(alarm);
+}
+
+static struct cache_extra cache_notrack_extra = {
+	.size 		= sizeof(struct alarm_list),
+	.add		= cache_notrack_add,
+	.update		= cache_notrack_update,
+	.destroy	= cache_notrack_destroy
+};
+
+static int notrack_pre_recv(const struct nlnetwork *net)
+{
+	unsigned int exp_seq;
+
+	/* 
+	 * Ignore error messages: Although this message type is not ever
+	 * generated in notrack mode, we don't want to crash the daemon 
+	 * if someone nuts mixes nack and notrack.
+	 */
+	if (net->flags & (NET_RESYNC | NET_NACK))
+		return 1;
+
+	/* 
+	 * Multicast sequence tracking: we keep track of multicast messages
+	 * although we don't do any explicit message recovery. So, why do
+	 * we do sequence tracking? Just to let know the sysadmin.
+	 *
+	 * Let t be 1 < t < RefreshTime. To ensure consistency, conntrackd
+	 * retransmit every t seconds a message with the state of a certain
+	 * entry even if such entry did not change. This mechanism also
+	 * provides passive resynchronization, in other words, there is
+	 * no facility to request a full synchronization from new nodes that
+	 * just joined the cluster, instead they just get resynchronized in
+	 * RefreshTime seconds at worst case.
+	 */
+	mcast_track_seq(net->seq, &exp_seq);
+
+	return 0;
+}
+
+static void notrack_post_send(const struct nlnetwork *n, struct us_conntrack *u)
+{
+}
+
+struct sync_mode notrack = {
+	.internal_cache_flags	= LIFETIME,
+	.external_cache_flags	= TIMER | LIFETIME,
+	.internal_cache_extra	= &cache_notrack_extra,
+	.pre_recv 		= notrack_pre_recv,
+	.post_send		= notrack_post_send,
+};