From 44e36b42a8378be1dcf7e6f8a1cb2710a8903387 Mon Sep 17 00:00:00 2001 From: "David S. Miller" Date: Thu, 24 Aug 2006 04:50:50 -0700 Subject: [XFRM]: Extract common hashing code into xfrm_hash.[ch] Signed-off-by: David S. Miller --- net/xfrm/xfrm_hash.h | 128 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 128 insertions(+) create mode 100644 net/xfrm/xfrm_hash.h (limited to 'net/xfrm/xfrm_hash.h') diff --git a/net/xfrm/xfrm_hash.h b/net/xfrm/xfrm_hash.h new file mode 100644 index 00000000000..d3abb0b7dc6 --- /dev/null +++ b/net/xfrm/xfrm_hash.h @@ -0,0 +1,128 @@ +#ifndef _XFRM_HASH_H +#define _XFRM_HASH_H + +#include +#include + +static inline unsigned int __xfrm4_addr_hash(xfrm_address_t *addr) +{ + return ntohl(addr->a4); +} + +static inline unsigned int __xfrm6_addr_hash(xfrm_address_t *addr) +{ + return ntohl(addr->a6[2] ^ addr->a6[3]); +} + +static inline unsigned int __xfrm4_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr) +{ + return ntohl(daddr->a4 ^ saddr->a4); +} + +static inline unsigned int __xfrm6_daddr_saddr_hash(xfrm_address_t *daddr, 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(xfrm_address_t *daddr, 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(xfrm_address_t *saddr, + unsigned short family, + unsigned int hmask) +{ + unsigned int h = family; + switch (family) { + case AF_INET: + h ^= __xfrm4_addr_hash(saddr); + break; + case AF_INET6: + h ^= __xfrm6_addr_hash(saddr); + break; + }; + return (h ^ (h >> 16)) & hmask; +} + +static inline unsigned int +__xfrm_spi_hash(xfrm_address_t *daddr, u32 spi, u8 proto, unsigned short family, + unsigned int hmask) +{ + unsigned int h = 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(struct xfrm_selector *sel, unsigned short family, unsigned int hmask) +{ + xfrm_address_t *daddr = &sel->daddr; + 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(xfrm_address_t *daddr, 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 */ -- cgit v1.2.3