5 #include <linux/skbuff.h>
6 #include <net/dsfield.h>
16 static inline int INET_ECN_is_ce(__u8 dsfield
)
18 return (dsfield
& INET_ECN_MASK
) == INET_ECN_CE
;
21 static inline int INET_ECN_is_not_ect(__u8 dsfield
)
23 return (dsfield
& INET_ECN_MASK
) == INET_ECN_NOT_ECT
;
26 static inline int INET_ECN_is_capable(__u8 dsfield
)
28 return (dsfield
& INET_ECN_ECT_0
);
31 static inline __u8
INET_ECN_encapsulate(__u8 outer
, __u8 inner
)
33 outer
&= ~INET_ECN_MASK
;
34 outer
|= !INET_ECN_is_ce(inner
) ? (inner
& INET_ECN_MASK
) :
39 #define INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= INET_ECN_ECT_0; } while (0)
40 #define INET_ECN_dontxmit(sk) \
41 do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
43 #define IP6_ECN_flow_init(label) do { \
44 (label) &= ~htonl(INET_ECN_MASK << 20); \
47 #define IP6_ECN_flow_xmit(sk, label) do { \
48 if (INET_ECN_is_capable(inet_sk(sk)->tos)) \
49 (label) |= __constant_htons(INET_ECN_ECT_0 << 4); \
52 static inline int IP_ECN_set_ce(struct iphdr
*iph
)
54 u32 check
= iph
->check
;
55 u32 ecn
= (iph
->tos
+ 1) & INET_ECN_MASK
;
58 * After the last operation we have (in binary):
59 * INET_ECN_NOT_ECT => 01
60 * INET_ECN_ECT_1 => 10
61 * INET_ECN_ECT_0 => 11
68 * The following gives us:
69 * INET_ECN_ECT_1 => check += htons(0xFFFD)
70 * INET_ECN_ECT_0 => check += htons(0xFFFE)
72 check
+= htons(0xFFFB) + htons(ecn
);
74 iph
->check
= check
+ (check
>=0xFFFF);
75 iph
->tos
|= INET_ECN_CE
;
79 static inline void IP_ECN_clear(struct iphdr
*iph
)
81 iph
->tos
&= ~INET_ECN_MASK
;
84 static inline void ipv4_copy_dscp(struct iphdr
*outer
, struct iphdr
*inner
)
86 u32 dscp
= ipv4_get_dsfield(outer
) & ~INET_ECN_MASK
;
87 ipv4_change_dsfield(inner
, INET_ECN_MASK
, dscp
);
92 static inline int IP6_ECN_set_ce(struct ipv6hdr
*iph
)
94 if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph
)))
96 *(u32
*)iph
|= htonl(INET_ECN_CE
<< 20);
100 static inline void IP6_ECN_clear(struct ipv6hdr
*iph
)
102 *(u32
*)iph
&= ~htonl(INET_ECN_MASK
<< 20);
105 static inline void ipv6_copy_dscp(struct ipv6hdr
*outer
, struct ipv6hdr
*inner
)
107 u32 dscp
= ipv6_get_dsfield(outer
) & ~INET_ECN_MASK
;
108 ipv6_change_dsfield(inner
, INET_ECN_MASK
, dscp
);
111 static inline int INET_ECN_set_ce(struct sk_buff
*skb
)
113 switch (skb
->protocol
) {
114 case __constant_htons(ETH_P_IP
):
115 if (skb
->nh
.raw
+ sizeof(struct iphdr
) <= skb
->tail
)
116 return IP_ECN_set_ce(skb
->nh
.iph
);
119 case __constant_htons(ETH_P_IPV6
):
120 if (skb
->nh
.raw
+ sizeof(struct ipv6hdr
) <= skb
->tail
)
121 return IP6_ECN_set_ce(skb
->nh
.ipv6h
);