[NETFILTER]: TCP conntrack: improve dead connection detection
Don't count window updates as retransmissions.
Signed-off-by: George Hansper <georgeh@anstat.com.au>
Signed-off-by: Patrick McHardy <kaber@trash.net>
diff --git a/include/linux/netfilter/nf_conntrack_tcp.h b/include/linux/netfilter/nf_conntrack_tcp.h
index b2feeff..6b01ba2 100644
--- a/include/linux/netfilter/nf_conntrack_tcp.h
+++ b/include/linux/netfilter/nf_conntrack_tcp.h
@@ -49,6 +49,7 @@
u_int32_t last_seq; /* Last sequence number seen in dir */
u_int32_t last_ack; /* Last sequence number seen in opposite dir */
u_int32_t last_end; /* Last seq + len */
+ u_int16_t last_win; /* Last window advertisement seen in dir */
};
#endif /* __KERNEL__ */
diff --git a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
index 75a7237..03ae9a0 100644
--- a/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
+++ b/net/ipv4/netfilter/ip_conntrack_proto_tcp.c
@@ -731,13 +731,15 @@
if (state->last_dir == dir
&& state->last_seq == seq
&& state->last_ack == ack
- && state->last_end == end)
+ && state->last_end == end
+ && state->last_win == win)
state->retrans++;
else {
state->last_dir = dir;
state->last_seq = seq;
state->last_ack = ack;
state->last_end = end;
+ state->last_win = win;
state->retrans = 0;
}
}
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index 9fc0ee6..238bbb5 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -688,13 +688,15 @@
if (state->last_dir == dir
&& state->last_seq == seq
&& state->last_ack == ack
- && state->last_end == end)
+ && state->last_end == end
+ && state->last_win == win)
state->retrans++;
else {
state->last_dir = dir;
state->last_seq = seq;
state->last_ack = ack;
state->last_end = end;
+ state->last_win = win;
state->retrans = 0;
}
}