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 *saddr,
  45                                        unsigned short family,
  46                                        unsigned int hmask)
  47 {
  48         unsigned int h = family;
  49         switch (family) {
  50         case AF_INET:
  51                 h ^= __xfrm4_addr_hash(saddr);
  52                 break;
  53         case AF_INET6:
  54                 h ^= __xfrm6_addr_hash(saddr);
  55                 break;
  56         };
  57         return (h ^ (h >> 16)) & hmask;
  58 }
  59
  60 static inline unsigned int
  61 __xfrm_spi_hash(xfrm_address_t *daddr, __be32 spi, u8 proto, unsigned short family,
  62                 unsigned int hmask)
  63 {
  64         unsigned int h = (__force u32)spi ^ proto;
  65         switch (family) {
  66         case AF_INET:
  67                 h ^= __xfrm4_addr_hash(daddr);
  68                 break;
  69         case AF_INET6:
  70                 h ^= __xfrm6_addr_hash(daddr);
  71                 break;
  72         }
  73         return (h ^ (h >> 10) ^ (h >> 20)) & hmask;
  74 }
  75
  76 static inline unsigned int __idx_hash(u32 index, unsigned int hmask)
  77 {
  78         return (index ^ (index >> 8)) & hmask;
  79 }
  80
  81 static inline unsigned int __sel_hash(struct xfrm_selector *sel, unsigned short family, unsigned int hmask)
  82 {
  83         xfrm_address_t *daddr = &sel->daddr;
  84         xfrm_address_t *saddr = &sel->saddr;
  85         unsigned int h = 0;
  86
  87         switch (family) {
  88         case AF_INET:
  89                 if (sel->prefixlen_d != 32 ||
  90                     sel->prefixlen_s != 32)
  91                         return hmask + 1;
  92
  93                 h = __xfrm4_daddr_saddr_hash(daddr, saddr);
  94                 break;
  95
  96         case AF_INET6:
  97                 if (sel->prefixlen_d != 128 ||
  98                     sel->prefixlen_s != 128)
  99                         return hmask + 1;
 100
 101                 h = __xfrm6_daddr_saddr_hash(daddr, saddr);
 102                 break;
 103         };
 104         h ^= (h >> 16);
 105         return h & hmask;
 106 }
 107
 108 static inline unsigned int __addr_hash(xfrm_address_t *daddr, xfrm_address_t *saddr, unsigned short family, unsigned int hmask)
 109 {
 110         unsigned int h = 0;
 111
 112         switch (family) {
 113         case AF_INET:
 114                 h = __xfrm4_daddr_saddr_hash(daddr, saddr);
 115                 break;
 116
 117         case AF_INET6:
 118                 h = __xfrm6_daddr_saddr_hash(daddr, saddr);
 119                 break;
 120         };
 121         h ^= (h >> 16);
 122         return h & hmask;
 123 }
 124
 125 extern struct hlist_head *xfrm_hash_alloc(unsigned int sz);
 126 extern void xfrm_hash_free(struct hlist_head *n, unsigned int sz);
 127
 128 #endif /* _XFRM_HASH_H */