net/xfrm/xfrm_hash.h

   1 #ifndef _XFRM_HASH_H
   2 #define _XFRM_HASH_H
   3
   4 #include <linux/xfrm.h>
   5 #include <linux/socket.h>
   6
   7 static inline unsigned int __xfrm4_addr_hash(xfrm_address_t *addr)
   8 {
   9         return ntohl(addr->a4);
  10 }
  11
  12 static inline unsigned int __xfrm6_addr_hash(xfrm_address_t *addr)
  13 {
  14         return ntohl(addr->a6[2] ^ addr->a6[3]);
  15 }
  16
  17 static inline unsigned int __xfrm4_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
  18 {
  19         return ntohl(daddr->a4 ^ saddr->a4);
  20 }
  21
  22 static inline unsigned int __xfrm6_daddr_saddr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr)
  23 {
  24         return ntohl(daddr->a6[2] ^ daddr->a6[3] ^
  25                      saddr->a6[2] ^ saddr->a6[3]);
  26 }
  27
  28 static inline unsigned int __xfrm_dst_hash(xfrm_address_t *daddr, xfrm_address_t *saddr,
  29                                            u32 reqid, unsigned short family,
  30                                            unsigned int hmask)
  31 {
  32         unsigned int h = family ^ reqid;
  33         switch (family) {
  34         case AF_INET:
  35                 h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
  36                 break;
  37         case AF_INET6:
  38                 h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
  39                 break;
  40         }
  41         return (h ^ (h >> 16)) & hmask;
  42 }
  43
  44 static inline unsigned __xfrm_src_hash(xfrm_address_t *daddr,
  45                                        xfrm_address_t *saddr,
  46                                        unsigned short family,
  47                                        unsigned int hmask)
  48 {
  49         unsigned int h = family;
  50         switch (family) {
  51         case AF_INET:
  52                 h ^= __xfrm4_daddr_saddr_hash(daddr, saddr);
  53                 break;
  54         case AF_INET6:
  55                 h ^= __xfrm6_daddr_saddr_hash(daddr, saddr);
  56                 break;
  57         };
  58         return (h ^ (h >> 16)) & hmask;
  59 }
  60
  61 static inline unsigned int
  62 __xfrm_spi_hash(xfrm_address_t *daddr, __be32 spi, u8 proto, unsigned short family,
  63                 unsigned int hmask)
  64 {
  65         unsigned int h = (__force u32)spi ^ proto;
  66         switch (family) {
  67         case AF_INET:
  68                 h ^= __xfrm4_addr_hash(daddr);
  69                 break;
  70         case AF_INET6:
  71                 h ^= __xfrm6_addr_hash(daddr);
  72                 break;
  73         }
  74         return (h ^ (h >> 10) ^ (h >> 20)) & hmask;
  75 }
  76
  77 static inline unsigned int __idx_hash(u32 index, unsigned int hmask)
  78 {
  79         return (index ^ (index >> 8)) & hmask;
  80 }
  81
  82 static inline unsigned int __sel_hash(struct xfrm_selector *sel, unsigned short family, unsigned int hmask)
  83 {
  84         xfrm_address_t *daddr = &sel->daddr;
  85         xfrm_address_t *saddr = &sel->saddr;
  86         unsigned int h = 0;
  87
  88         switch (family) {
  89         case AF_INET:
  90                 if (sel->prefixlen_d != 32 ||
  91                     sel->prefixlen_s != 32)
  92                         return hmask + 1;
  93
  94                 h = __xfrm4_daddr_saddr_hash(daddr, saddr);
  95                 break;
  96
  97         case AF_INET6:
  98                 if (sel->prefixlen_d != 128 ||
  99                     sel->prefixlen_s != 128)
 100                         return hmask + 1;
 101
 102                 h = __xfrm6_daddr_saddr_hash(daddr, saddr);
 103                 break;
 104         };
 105         h ^= (h >> 16);
 106         return h & hmask;
 107 }
 108
 109 static inline unsigned int __addr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, unsigned int hmask)
 110 {
 111         unsigned int h = 0;
 112
 113         switch (family) {
 114         case AF_INET:
 115                 h = __xfrm4_daddr_saddr_hash(daddr, saddr);
 116                 break;
 117
 118         case AF_INET6:
 119                 h = __xfrm6_daddr_saddr_hash(daddr, saddr);
 120                 break;
 121         };
 122         h ^= (h >> 16);
 123         return h & hmask;
 124 }
 125
 126 extern struct hlist_head *xfrm_hash_alloc(unsigned int sz);
 127 extern void xfrm_hash_free(struct hlist_head *n, unsigned int sz);
 128
 129 #endif /* _XFRM_HASH_H */