[NETFILTER] x_tables: Abstraction layer for {ip,ip6,arp}_tables

This monster-patch tries to do the best job for unifying the data
structures and backend interfaces for the three evil clones ip_tables,
ip6_tables and arp_tables.  In an ideal world we would never have
allowed this kind of copy+paste programming... but well, our world
isn't (yet?) ideal.

o introduce a new x_tables module
o {ip,arp,ip6}_tables depend on this x_tables module
o registration functions for tables, matches and targets are only
  wrappers around x_tables provided functions
o all matches/targets that are used from ip_tables and ip6_tables
  are now implemented as xt_FOOBAR.c files and provide module aliases
  to ipt_FOOBAR and ip6t_FOOBAR
o header files for xt_matches are in include/linux/netfilter/,
  include/linux/netfilter_{ipv4,ipv6} contains compatibility wrappers
  around the xt_FOOBAR.h headers

Based on this patchset we're going to further unify the code,
gradually getting rid of all the layer 3 specific assumptions.

Signed-off-by: Harald Welte <laforge@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 36 insertions, 0 deletions

diff --git a/include/linux/netfilter/xt_tcpudp.h b/include/linux/netfilter/xt_tcpudp.h
new file mode 100644
index 00000000000000..78bc65f11adf1b
--- /dev/null
+++ b/include/linux/netfilter/xt_tcpudp.h
@@ -0,0 +1,36 @@
+#ifndef _XT_TCPUDP_H
+#define _XT_TCPUDP_H
+
+/* TCP matching stuff */
+struct xt_tcp
+{
+	u_int16_t spts[2];			/* Source port range. */
+	u_int16_t dpts[2];			/* Destination port range. */
+	u_int8_t option;			/* TCP Option iff non-zero*/
+	u_int8_t flg_mask;			/* TCP flags mask byte */
+	u_int8_t flg_cmp;			/* TCP flags compare byte */
+	u_int8_t invflags;			/* Inverse flags */
+};
+
+/* Values for "inv" field in struct ipt_tcp. */
+#define XT_TCP_INV_SRCPT	0x01	/* Invert the sense of source ports. */
+#define XT_TCP_INV_DSTPT	0x02	/* Invert the sense of dest ports. */
+#define XT_TCP_INV_FLAGS	0x04	/* Invert the sense of TCP flags. */
+#define XT_TCP_INV_OPTION	0x08	/* Invert the sense of option test. */
+#define XT_TCP_INV_MASK		0x0F	/* All possible flags. */
+
+/* UDP matching stuff */
+struct xt_udp
+{
+	u_int16_t spts[2];			/* Source port range. */
+	u_int16_t dpts[2];			/* Destination port range. */
+	u_int8_t invflags;			/* Inverse flags */
+};
+
+/* Values for "invflags" field in struct ipt_udp. */
+#define XT_UDP_INV_SRCPT	0x01	/* Invert the sense of source ports. */
+#define XT_UDP_INV_DSTPT	0x02	/* Invert the sense of dest ports. */
+#define XT_UDP_INV_MASK	0x03	/* All possible flags. */
+
+
+#endif