[NETFILTER]: TCP conntrack: factorize out the PUSH flag
The PUSH flag is accepted with every other valid combination.
Let's get it out of the tcp_valid_flags table and reduce the
number of combinations we have to handle. This does not
significantly reduce the table size however (8 bytes).
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index 926e302..a136362 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c
@@ -764,27 +764,18 @@
#define TH_ECE 0x40
#define TH_CWR 0x80
-/* table of valid flag combinations - ECE and CWR are always valid */
-static u8 tcp_valid_flags[(TH_FIN|TH_SYN|TH_RST|TH_PUSH|TH_ACK|TH_URG) + 1] =
+/* table of valid flag combinations - PUSH, ECE and CWR are always valid */
+static u8 tcp_valid_flags[(TH_FIN|TH_SYN|TH_RST|TH_ACK|TH_URG) + 1] =
{
[TH_SYN] = 1,
- [TH_SYN|TH_PUSH] = 1,
[TH_SYN|TH_URG] = 1,
- [TH_SYN|TH_PUSH|TH_URG] = 1,
[TH_SYN|TH_ACK] = 1,
- [TH_SYN|TH_ACK|TH_PUSH] = 1,
[TH_RST] = 1,
- [TH_RST|TH_PUSH] = 1,
[TH_RST|TH_ACK] = 1,
- [TH_RST|TH_ACK|TH_PUSH] = 1,
[TH_FIN|TH_ACK] = 1,
- [TH_ACK] = 1,
- [TH_ACK|TH_PUSH] = 1,
- [TH_ACK|TH_URG] = 1,
- [TH_ACK|TH_URG|TH_PUSH] = 1,
- [TH_FIN|TH_ACK|TH_PUSH] = 1,
[TH_FIN|TH_ACK|TH_URG] = 1,
- [TH_FIN|TH_ACK|TH_URG|TH_PUSH] = 1,
+ [TH_ACK] = 1,
+ [TH_ACK|TH_URG] = 1,
};
/* Protect conntrack agaist broken packets. Code taken from ipt_unclean.c. */
@@ -831,7 +822,7 @@
}
/* Check TCP flags. */
- tcpflags = (((u_int8_t *)th)[13] & ~(TH_ECE|TH_CWR));
+ tcpflags = (((u_int8_t *)th)[13] & ~(TH_ECE|TH_CWR|TH_PUSH));
if (!tcp_valid_flags[tcpflags]) {
if (LOG_INVALID(IPPROTO_TCP))
nf_log_packet(pf, 0, skb, NULL, NULL, NULL,