diff options
Diffstat (limited to 'net/xfrm/xfrm_hash.h')
-rw-r--r-- | net/xfrm/xfrm_hash.h | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_hash.h b/net/xfrm/xfrm_hash.h new file mode 100644 index 00000000..7199d78b --- /dev/null +++ b/net/xfrm/xfrm_hash.h @@ -0,0 +1,136 @@ +#ifndef _XFRM_HASH_H +#define _XFRM_HASH_H + +#include <linux/xfrm.h> +#include <linux/socket.h> + +static inline unsigned int __xfrm4_addr_hash(const xfrm_address_t *addr) +{ + return ntohl(addr->a4); +} + +static inline unsigned int __xfrm6_addr_hash(const xfrm_address_t *addr) +{ + return ntohl(addr->a6[2] ^ addr->a6[3]); +} + +static inline unsigned int __xfrm4_daddr_saddr_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr) +{ + u32 sum = (__force u32)daddr->a4 + (__force u32)saddr->a4; + return ntohl((__force __be32)sum); +} + +static inline unsigned int __xfrm6_daddr_saddr_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr) +{ + return ntohl(daddr->a6[2] ^ daddr->a6[3] ^ + saddr->a6[2] ^ saddr->a6[3]); +} + +static inline unsigned int __xfrm_dst_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr, + u32 reqid, unsigned short family, + unsigned int hmask) +{ + unsigned int h = family ^ reqid; + switch (family) { + case AF_INET: + h ^= __xfrm4_daddr_saddr_hash(daddr, saddr); + break; + case AF_INET6: + h ^= __xfrm6_daddr_saddr_hash(daddr, saddr); + break; + } + return (h ^ (h >> 16)) & hmask; +} + +static inline unsigned __xfrm_src_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr, + unsigned short family, + unsigned int hmask) +{ + unsigned int h = family; + switch (family) { + case AF_INET: + h ^= __xfrm4_daddr_saddr_hash(daddr, saddr); + break; + case AF_INET6: + h ^= __xfrm6_daddr_saddr_hash(daddr, saddr); + break; + } + return (h ^ (h >> 16)) & hmask; +} + +static inline unsigned int +__xfrm_spi_hash(const xfrm_address_t *daddr, __be32 spi, u8 proto, + unsigned short family, unsigned int hmask) +{ + unsigned int h = (__force u32)spi ^ proto; + switch (family) { + case AF_INET: + h ^= __xfrm4_addr_hash(daddr); + break; + case AF_INET6: + h ^= __xfrm6_addr_hash(daddr); + break; + } + return (h ^ (h >> 10) ^ (h >> 20)) & hmask; +} + +static inline unsigned int __idx_hash(u32 index, unsigned int hmask) +{ + return (index ^ (index >> 8)) & hmask; +} + +static inline unsigned int __sel_hash(const struct xfrm_selector *sel, + unsigned short family, unsigned int hmask) +{ + const xfrm_address_t *daddr = &sel->daddr; + const xfrm_address_t *saddr = &sel->saddr; + unsigned int h = 0; + + switch (family) { + case AF_INET: + if (sel->prefixlen_d != 32 || + sel->prefixlen_s != 32) + return hmask + 1; + + h = __xfrm4_daddr_saddr_hash(daddr, saddr); + break; + + case AF_INET6: + if (sel->prefixlen_d != 128 || + sel->prefixlen_s != 128) + return hmask + 1; + + h = __xfrm6_daddr_saddr_hash(daddr, saddr); + break; + } + h ^= (h >> 16); + return h & hmask; +} + +static inline unsigned int __addr_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr, + unsigned short family, unsigned int hmask) +{ + unsigned int h = 0; + + switch (family) { + case AF_INET: + h = __xfrm4_daddr_saddr_hash(daddr, saddr); + break; + + case AF_INET6: + h = __xfrm6_daddr_saddr_hash(daddr, saddr); + break; + } + h ^= (h >> 16); + return h & hmask; +} + +extern struct hlist_head *xfrm_hash_alloc(unsigned int sz); +extern void xfrm_hash_free(struct hlist_head *n, unsigned int sz); + +#endif /* _XFRM_HASH_H */ |