Hi all,
I think that the chunkmap field in struct xt_sctp_info is
too large: we have 256 chunk types and it's a bitfield,
so the table should be 256 bits (8 uint32_t) instead
of 64 uint32_t.
I updated the size of the table, and I did some cosmetic
changes in SCTP_CHUNKMAP_* macros (use a mask instead of
a modulo).
netfilter/xt_sctp.h | 30 ++++++++++++++++--------------
netfilter_ipv4/ipt_sctp.h | 30 ++++++++++++++++--------------
2 files changed, 32 insertions(+), 28 deletions(-)
Can someone have a look at it ? Please CC me for any replies
as I'm not on the list.
Thanks,
Olivier
diff -r ce4087e26684 include/linux/netfilter/xt_sctp.h
--- a/include/linux/netfilter/xt_sctp.h Wed Jan 28 20:01:08 2009 +0000
+++ b/include/linux/netfilter/xt_sctp.h Fri Jan 30 16:25:55 2009 +0100
@@ -15,11 +15,13 @@
#define XT_NUM_SCTP_FLAGS 4
+#define sizeof_bits(type) (sizeof(type) * 8)
+
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 */
+ u_int32_t chunkmap[256 / sizeof_bits(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 */
@@ -33,24 +35,24 @@
u_int32_t invflags;
};
-#define bytes(type) (sizeof(type) * 8)
+#define SCTP_MODULO(chunktype, type) (chunktype & (sizeof_bits(type)-1))
-#define SCTP_CHUNKMAP_SET(chunkmap, type) \
- do { \
- (chunkmap)[type / bytes(u_int32_t)] |= \
- 1 << (type % bytes(u_int32_t)); \
+#define SCTP_CHUNKMAP_SET(chunkmap, chunktype) \
+ do { \
+ chunkmap[chunktype / sizeof_bits(u_int32_t)] |= \
+ 1 << SCTP_MODULO(chunktype, u_int32_t); \
} while (0)
-#define SCTP_CHUNKMAP_CLEAR(chunkmap, type) \
- do { \
- (chunkmap)[type / bytes(u_int32_t)] &= \
- ~(1 << (type % bytes(u_int32_t))); \
+#define SCTP_CHUNKMAP_CLEAR(chunkmap, chunktype) \
+ do { \
+ chunkmap[chunktype / sizeof_bits(u_int32_t)] &= \
+ ~(1 << SCTP_MODULO(chunktype, 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_IS_SET(chunkmap, chunktype) \
+({ \
+ (chunkmap[chunktype / sizeof_bits(u_int32_t)] & \
+ (1 << SCTP_MODULO(chunktype, u_int32_t))) ? 1 : 0; \
})
#define SCTP_CHUNKMAP_RESET(chunkmap) \
diff -r ce4087e26684 include/linux/netfilter_ipv4/ipt_sctp.h
--- a/include/linux/netfilter_ipv4/ipt_sctp.h Wed Jan 28 20:01:08 2009 +0000
+++ b/include/linux/netfilter_ipv4/ipt_sctp.h Fri Jan 30 16:25:55 2009 +0100
@@ -16,11 +16,13 @@
#define IPT_NUM_SCTP_FLAGS 4
+#define sizeof_bits(type) (sizeof(type) * 8)
+
struct ipt_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 */
+ u_int32_t chunkmap[256 / sizeof_bits(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 */
@@ -34,24 +36,24 @@
u_int32_t invflags;
};
-#define bytes(type) (sizeof(type) * 8)
+#define SCTP_MODULO(chunktype, type) (chunktype & (sizeof_bits(type)-1))
-#define SCTP_CHUNKMAP_SET(chunkmap, type) \
- do { \
- chunkmap[type / bytes(u_int32_t)] |= \
- 1 << (type % bytes(u_int32_t)); \
+#define SCTP_CHUNKMAP_SET(chunkmap, chunktype) \
+ do { \
+ chunkmap[chunktype / sizeof_bits(u_int32_t)] |= \
+ 1 << SCTP_MODULO(chunktype, u_int32_t); \
} while (0)
-#define SCTP_CHUNKMAP_CLEAR(chunkmap, type) \
- do { \
- chunkmap[type / bytes(u_int32_t)] &= \
- ~(1 << (type % bytes(u_int32_t))); \
+#define SCTP_CHUNKMAP_CLEAR(chunkmap, chunktype) \
+ do { \
+ chunkmap[chunktype / sizeof_bits(u_int32_t)] &= \
+ ~(1 << SCTP_MODULO(chunktype, 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_IS_SET(chunkmap, chunktype) \
+({ \
+ (chunkmap[chunktype / sizeof_bits(u_int32_t)] & \
+ (1 << SCTP_MODULO(chunktype, u_int32_t))) ? 1 : 0; \
})
#define SCTP_CHUNKMAP_RESET(chunkmap) \
