diff options
Diffstat (limited to 'net/xfrm/xfrm_hash.h')
| -rw-r--r-- | net/xfrm/xfrm_hash.h | 199 |
1 files changed, 199 insertions, 0 deletions
diff --git a/net/xfrm/xfrm_hash.h b/net/xfrm/xfrm_hash.h new file mode 100644 index 000000000..d12bb906c --- /dev/null +++ b/net/xfrm/xfrm_hash.h @@ -0,0 +1,199 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +#ifndef _XFRM_HASH_H +#define _XFRM_HASH_H + +#include <linux/xfrm.h> +#include <linux/socket.h> +#include <linux/jhash.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 jhash2((__force u32 *)addr->a6, 4, 0); +} + +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 __xfrm6_addr_hash(daddr) ^ __xfrm6_addr_hash(saddr); +} + +static inline u32 __bits2mask32(__u8 bits) +{ + u32 mask32 = 0xffffffff; + + if (bits == 0) + mask32 = 0; + else if (bits < 32) + mask32 <<= (32 - bits); + + return mask32; +} + +static inline unsigned int __xfrm4_dpref_spref_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr, + __u8 dbits, + __u8 sbits) +{ + return jhash_2words(ntohl(daddr->a4) & __bits2mask32(dbits), + ntohl(saddr->a4) & __bits2mask32(sbits), + 0); +} + +static inline unsigned int __xfrm6_pref_hash(const xfrm_address_t *addr, + __u8 prefixlen) +{ + unsigned int pdw; + unsigned int pbi; + u32 initval = 0; + + pdw = prefixlen >> 5; /* num of whole u32 in prefix */ + pbi = prefixlen & 0x1f; /* num of bits in incomplete u32 in prefix */ + + if (pbi) { + __be32 mask; + + mask = htonl((0xffffffff) << (32 - pbi)); + + initval = (__force u32)(addr->a6[pdw] & mask); + } + + return jhash2((__force u32 *)addr->a6, pdw, initval); +} + +static inline unsigned int __xfrm6_dpref_spref_hash(const xfrm_address_t *daddr, + const xfrm_address_t *saddr, + __u8 dbits, + __u8 sbits) +{ + return __xfrm6_pref_hash(daddr, dbits) ^ + __xfrm6_pref_hash(saddr, sbits); +} + +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 int __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 +__xfrm_seq_hash(u32 seq, unsigned int hmask) +{ + unsigned int h = seq; + 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, + u8 dbits, u8 sbits) +{ + 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 < dbits || + sel->prefixlen_s < sbits) + return hmask + 1; + + h = __xfrm4_dpref_spref_hash(daddr, saddr, dbits, sbits); + break; + + case AF_INET6: + if (sel->prefixlen_d < dbits || + sel->prefixlen_s < sbits) + return hmask + 1; + + h = __xfrm6_dpref_spref_hash(daddr, saddr, dbits, sbits); + 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, + u8 dbits, u8 sbits) +{ + unsigned int h = 0; + + switch (family) { + case AF_INET: + h = __xfrm4_dpref_spref_hash(daddr, saddr, dbits, sbits); + break; + + case AF_INET6: + h = __xfrm6_dpref_spref_hash(daddr, saddr, dbits, sbits); + break; + } + h ^= (h >> 16); + return h & hmask; +} + +struct hlist_head *xfrm_hash_alloc(unsigned int sz); +void xfrm_hash_free(struct hlist_head *n, unsigned int sz); + +#endif /* _XFRM_HASH_H */ |