[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, 107 insertions, 0 deletions

diff --git a/include/linux/netfilter/xt_sctp.h b/include/linux/netfilter/xt_sctp.h
new file mode 100644
index 0000000000000..b157897e77921
--- /dev/null
+++ b/include/linux/netfilter/xt_sctp.h
@@ -0,0 +1,107 @@
+#ifndef _XT_SCTP_H_
+#define _XT_SCTP_H_
+
+#define XT_SCTP_SRC_PORTS	        0x01
+#define XT_SCTP_DEST_PORTS	        0x02
+#define XT_SCTP_CHUNK_TYPES		0x04
+
+#define XT_SCTP_VALID_FLAGS		0x07
+
+#define ELEMCOUNT(x) (sizeof(x)/sizeof(x[0]))
+
+
+struct xt_sctp_flag_info {
+	u_int8_t chunktype;
+	u_int8_t flag;
+	u_int8_t flag_mask;
+};
+
+#define XT_NUM_SCTP_FLAGS	4
+
+struct xt_sctp_info {
+	u_int16_t dpts[2];  /* Min, Max */
+	u_int16_t spts[2];  /* Min, Max */
+
+	u_int32_t chunkmap[256 / sizeof (u_int32_t)];  /* Bit mask of chunks to be matched according to RFC 2960 */
+
+#define SCTP_CHUNK_MATCH_ANY   0x01  /* Match if any of the chunk types are present */
+#define SCTP_CHUNK_MATCH_ALL   0x02  /* Match if all of the chunk types are present */
+#define SCTP_CHUNK_MATCH_ONLY  0x04  /* Match if these are the only chunk types present */
+
+	u_int32_t chunk_match_type;
+	struct xt_sctp_flag_info flag_info[XT_NUM_SCTP_FLAGS];
+	int flag_count;
+
+	u_int32_t flags;
+	u_int32_t invflags;
+};
+
+#define bytes(type) (sizeof(type) * 8)
+
+#define SCTP_CHUNKMAP_SET(chunkmap, type) 		\
+	do { 						\
+		chunkmap[type / bytes(u_int32_t)] |= 	\
+			1 << (type % bytes(u_int32_t));	\
+	} while (0)
+
+#define SCTP_CHUNKMAP_CLEAR(chunkmap, type)		 	\
+	do {							\
+		chunkmap[type / bytes(u_int32_t)] &= 		\
+			~(1 << (type % bytes(u_int32_t)));	\
+	} while (0)
+
+#define SCTP_CHUNKMAP_IS_SET(chunkmap, type) 			\
+({								\
+	(chunkmap[type / bytes (u_int32_t)] & 			\
+		(1 << (type % bytes (u_int32_t)))) ? 1: 0;	\
+})
+
+#define SCTP_CHUNKMAP_RESET(chunkmap) 				\
+	do {							\
+		int i; 						\
+		for (i = 0; i < ELEMCOUNT(chunkmap); i++)	\
+			chunkmap[i] = 0;			\
+	} while (0)
+
+#define SCTP_CHUNKMAP_SET_ALL(chunkmap) 			\
+	do {							\
+		int i; 						\
+		for (i = 0; i < ELEMCOUNT(chunkmap); i++) 	\
+			chunkmap[i] = ~0;			\
+	} while (0)
+
+#define SCTP_CHUNKMAP_COPY(destmap, srcmap) 			\
+	do {							\
+		int i; 						\
+		for (i = 0; i < ELEMCOUNT(chunkmap); i++) 	\
+			destmap[i] = srcmap[i];			\
+	} while (0)
+
+#define SCTP_CHUNKMAP_IS_CLEAR(chunkmap) 		\
+({							\
+	int i; 						\
+	int flag = 1;					\
+	for (i = 0; i < ELEMCOUNT(chunkmap); i++) {	\
+		if (chunkmap[i]) {			\
+			flag = 0;			\
+			break;				\
+		}					\
+	}						\
+        flag;						\
+})
+
+#define SCTP_CHUNKMAP_IS_ALL_SET(chunkmap) 		\
+({							\
+	int i; 						\
+	int flag = 1;					\
+	for (i = 0; i < ELEMCOUNT(chunkmap); i++) {	\
+		if (chunkmap[i] != ~0) {		\
+			flag = 0;			\
+				break;			\
+		}					\
+	}						\
+        flag;						\
+})
+
+#endif /* _XT_SCTP_H_ */
+