include/net/inet_ecn.h

   1 #ifndef _INET_ECN_H_
   2 #define _INET_ECN_H_
   3
   4 #include <linux/config.h>
   5
   6 #ifdef CONFIG_INET_ECN
   7
   8 static inline int INET_ECN_is_ce(__u8 dsfield)
   9 {
  10         return (dsfield&3) == 3;
  11 }
  12
  13 static inline int INET_ECN_is_not_ce(__u8 dsfield)
  14 {
  15         return (dsfield&3) == 2;
  16 }
  17
  18 static inline int INET_ECN_is_capable(__u8 dsfield)
  19 {
  20         return (dsfield&2);
  21 }
  22
  23 static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
  24 {
  25         outer &= ~3;
  26         if (INET_ECN_is_capable(inner))
  27                 outer |= (inner & 3);
  28         return outer;
  29 }
  30
  31 #define INET_ECN_xmit(sk) do { (sk)->protinfo.af_inet.tos |= 2; } while (0)
  32 #define INET_ECN_dontxmit(sk) do { (sk)->protinfo.af_inet.tos &= ~3; } while (0)
  33
  34 #define IP6_ECN_flow_init(label) do {   \
  35       (label) &= ~htonl(3<<20);         \
  36     } while (0)
  37
  38 #define IP6_ECN_flow_xmit(sk, label) do {                       \
  39         if (INET_ECN_is_capable((sk)->protinfo.af_inet.tos))    \
  40                 (label) |= __constant_htons(2 << 4);            \
  41     } while (0)
  42
  43
  44 #else
  45 #define INET_ECN_is_ce(x...)            (0)
  46 #define INET_ECN_is_not_ce(x...)        (0)
  47 #define INET_ECN_is_capable(x...)       (0)
  48 #define INET_ECN_encapsulate(x, y)      (x)
  49 #define IP6_ECN_flow_init(x...)         do { } while (0)
  50 #define IP6_ECN_flow_xmit(x...)         do { } while (0)
  51 #define INET_ECN_xmit(x...)             do { } while (0)
  52 #define INET_ECN_dontxmit(x...)         do { } while (0)
  53 #endif
  54
  55 static inline void IP_ECN_set_ce(struct iphdr *iph)
  56 {
  57         u32 check = iph->check;
  58         check += __constant_htons(0xFFFE);
  59         iph->check = check + (check>=0xFFFF);
  60         iph->tos |= 1;
  61 }
  62
  63 struct ipv6hdr;
  64
  65 static inline void IP6_ECN_set_ce(struct ipv6hdr *iph)
  66 {
  67         *(u32*)iph |= htonl(1<<20);
  68 }
  69
  70 #define ip6_get_dsfield(iph) ((ntohs(*(u16*)(iph)) >> 4) & 0xFF)
  71
  72 #endif