src: add state polling support (oppossed to current event-driven)

This patch adds the clause PollSecs that changes the normal
behaviour of conntrackd. With PollSecs set to > 0, conntrackd
polls every N seconds the entries.

This is the opposed behaviour of an event-driven behaviour but may
be useful for those that have really strong limitations in terms of
CPU consumption and want to perform a relaxed replication.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

3 files changed, 36 insertions, 0 deletions

diff --git a/doc/sync/alarm/conntrackd.conf b/doc/sync/alarm/conntrackd.conf
index 528ff8f..3479a83 100644
--- a/doc/sync/alarm/conntrackd.conf
+++ b/doc/sync/alarm/conntrackd.conf
@@ -183,6 +183,18 @@ General {
 	#
 	SocketBufferSizeMaxGrowth 8388608
 
+	# 
+	# By default, the daemon receives state updates following an
+	# event-driven model. You can modify this behaviour by switching to
+	# polling mode with the PollSecs clause. This clause tells conntrackd
+	# to dump the states in the kernel every N seconds. With regards to
+	# synchronization mode, the polling mode can only guarantee that
+	# long-lifetime states are recovered. The main advantage of this method
+	# is the reduction in the state replication at the cost of reducing the
+	# chances of recovering connections.
+	#
+	# PollSecs 15
+
 	#
 	# The daemon prioritizes the handling of state-change events coming
 	# from the core. With this clause, you can set the maximum number of
diff --git a/doc/sync/ftfw/conntrackd.conf b/doc/sync/ftfw/conntrackd.conf
index 2e60f2c..77ef76c 100644
--- a/doc/sync/ftfw/conntrackd.conf
+++ b/doc/sync/ftfw/conntrackd.conf
@@ -191,6 +191,18 @@ General {
 	#
 	SocketBufferSizeMaxGrowth 8388608
 
+	# 
+	# By default, the daemon receives state updates following an
+	# event-driven model. You can modify this behaviour by switching to
+	# polling mode with the PollSecs clause. This clause tells conntrackd
+	# to dump the states in the kernel every N seconds. With regards to
+	# synchronization mode, the polling mode can only guarantee that
+	# long-lifetime states are recovered. The main advantage of this method
+	# is the reduction in the state replication at the cost of reducing the
+	# chances of recovering connections.
+	#
+	# PollSecs 15
+
 	#
 	# The daemon prioritizes the handling of state-change events coming
 	# from the core. With this clause, you can set the maximum number of
diff --git a/doc/sync/notrack/conntrackd.conf b/doc/sync/notrack/conntrackd.conf
index 7f8c8a3..5abf589 100644
--- a/doc/sync/notrack/conntrackd.conf
+++ b/doc/sync/notrack/conntrackd.conf
@@ -173,6 +173,18 @@ General {
 	#
 	SocketBufferSizeMaxGrowth 8388608
 
+	# 
+	# By default, the daemon receives state updates following an
+	# event-driven model. You can modify this behaviour by switching to
+	# polling mode with the PollSecs clause. This clause tells conntrackd
+	# to dump the states in the kernel every N seconds. With regards to
+	# synchronization mode, the polling mode can only guarantee that
+	# long-lifetime states are recovered. The main advantage of this method
+	# is the reduction in the state replication at the cost of reducing the
+	# chances of recovering connections.
+	#
+	# PollSecs 15
+
 	#
 	# The daemon prioritizes the handling of state-change events coming
 	# from the core. With this clause, you can set the maximum number of