[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, 18 insertions, 0 deletions

diff --git a/include/linux/netfilter/xt_string.h b/include/linux/netfilter/xt_string.h
new file mode 100644
index 0000000000000..3b3419f2637d0
--- /dev/null
+++ b/include/linux/netfilter/xt_string.h
@@ -0,0 +1,18 @@
+#ifndef _XT_STRING_H
+#define _XT_STRING_H
+
+#define XT_STRING_MAX_PATTERN_SIZE 128
+#define XT_STRING_MAX_ALGO_NAME_SIZE 16
+
+struct xt_string_info
+{
+	u_int16_t from_offset;
+	u_int16_t to_offset;
+	char	  algo[XT_STRING_MAX_ALGO_NAME_SIZE];
+	char 	  pattern[XT_STRING_MAX_PATTERN_SIZE];
+	u_int8_t  patlen;
+	u_int8_t  invert;
+	struct ts_config __attribute__((aligned(8))) *config;
+};
+
+#endif /*_XT_STRING_H*/