diff options
Diffstat (limited to 'kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h')
| -rw-r--r-- | kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h | 55 |
1 files changed, 24 insertions, 31 deletions
diff --git a/kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h b/kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h index f98f5fb..307c1fe 100644 --- a/kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h +++ b/kernel/linux2.5/include/linux/netfilter_bridge/ebt_among.h @@ -4,9 +4,11 @@ #define EBT_AMONG_DST 0x01 #define EBT_AMONG_SRC 0x02 -/* Write-once-read-many hash table, used for checking if a given - * MAC address belongs to a set or not. It remembers up to 256 - * addresses. +/* Grzegorz Borowiak <grzes@gnu.univ.gda.pl> 2003 + * + * Write-once-read-many hash table, used for checking if a given + * MAC address belongs to a set or not and possibly for checking + * if it is related with a given IPv4 address. * * The hash value of an address is its last byte. * @@ -25,48 +27,39 @@ * if they are the same we compare 2 first. * * Yes, it is a memory overhead, but in 2003 AD, who cares? - * - * `next_ofs' contains a "serialized" pointer to the next tuple in - * the synonym list. It is a difference between address of the next - * tuple and address of the entire wormhash structure, in bytes - * or 0 if there is no next tuple. - * - * `table' contains begins of the synonym lists for - * - * This was introduced to make wormhash structure movable. As you may - * guess, once structure is passed to the kernel, the real pointers - * would become invalid. Also comparison would not work if they were - * built of absolute pointers. - * - * From the other side, using indices of the `pool' array would be - * slower. CPU would have to multiply index * size of tuple at each - * access to a tuple and add this to the address of the beginning - * of the `pool' array. - * - * Summary: - * - * The code is damn unreadable and unclear, but - and that's the - * point - effective. */ struct ebt_mac_wormhash_tuple { - int next_ofs; uint32_t cmp[2]; + uint32_t ip; }; struct ebt_mac_wormhash { - int table[256]; - struct ebt_mac_wormhash_tuple pool[256]; + int table[257]; + int poolsize; + struct ebt_mac_wormhash_tuple pool[0]; }; +#define ebt_mac_wormhash_size(x) ((x) ? sizeof(struct ebt_mac_wormhash) \ + + (x)->poolsize * sizeof(struct ebt_mac_wormhash_tuple) : 0) + struct ebt_among_info { - uint32_t bitmask; - struct ebt_mac_wormhash wh_dst; - struct ebt_mac_wormhash wh_src; + int wh_dst_ofs; + int wh_src_ofs; + int bitmask; }; + +#define EBT_AMONG_DST_NEG 0x1 +#define EBT_AMONG_SRC_NEG 0x2 + +#define ebt_among_wh_dst(x) ((x)->wh_dst_ofs ? \ + (struct ebt_mac_wormhash*)((char*)(x) + (x)->wh_dst_ofs) : NULL) +#define ebt_among_wh_src(x) ((x)->wh_src_ofs ? \ + (struct ebt_mac_wormhash*)((char*)(x) + (x)->wh_src_ofs) : NULL) + #define EBT_AMONG_MATCH "among" #endif |