5 #include <linux/skbuff.h>
7 #include <net/inet_sock.h>
8 #include <net/dsfield.h>
18 static inline int INET_ECN_is_ce(__u8 dsfield
)
20 return (dsfield
& INET_ECN_MASK
) == INET_ECN_CE
;
23 static inline int INET_ECN_is_not_ect(__u8 dsfield
)
25 return (dsfield
& INET_ECN_MASK
) == INET_ECN_NOT_ECT
;
28 static inline int INET_ECN_is_capable(__u8 dsfield
)
30 return (dsfield
& INET_ECN_ECT_0
);
33 static inline __u8
INET_ECN_encapsulate(__u8 outer
, __u8 inner
)
35 outer
&= ~INET_ECN_MASK
;
36 outer
|= !INET_ECN_is_ce(inner
) ? (inner
& INET_ECN_MASK
) :
41 #define INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= INET_ECN_ECT_0; } while (0)
42 #define INET_ECN_dontxmit(sk) \
43 do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
45 #define IP6_ECN_flow_init(label) do { \
46 (label) &= ~htonl(INET_ECN_MASK << 20); \
49 #define IP6_ECN_flow_xmit(sk, label) do { \
50 if (INET_ECN_is_capable(inet_sk(sk)->tos)) \
51 (label) |= htonl(INET_ECN_ECT_0 << 20); \
54 static inline int IP_ECN_set_ce(struct iphdr
*iph
)
56 u32 check
= (__force u32
)iph
->check
;
57 u32 ecn
= (iph
->tos
+ 1) & INET_ECN_MASK
;
60 * After the last operation we have (in binary):
61 * INET_ECN_NOT_ECT => 01
62 * INET_ECN_ECT_1 => 10
63 * INET_ECN_ECT_0 => 11
70 * The following gives us:
71 * INET_ECN_ECT_1 => check += htons(0xFFFD)
72 * INET_ECN_ECT_0 => check += htons(0xFFFE)
74 check
+= (__force u16
)htons(0xFFFB) + (__force u16
)htons(ecn
);
76 iph
->check
= (__force __sum16
)(check
+ (check
>=0xFFFF));
77 iph
->tos
|= INET_ECN_CE
;
81 static inline void IP_ECN_clear(struct iphdr
*iph
)
83 iph
->tos
&= ~INET_ECN_MASK
;
86 static inline void ipv4_copy_dscp(struct iphdr
*outer
, struct iphdr
*inner
)
88 u32 dscp
= ipv4_get_dsfield(outer
) & ~INET_ECN_MASK
;
89 ipv4_change_dsfield(inner
, INET_ECN_MASK
, dscp
);
94 static inline int IP6_ECN_set_ce(struct ipv6hdr
*iph
)
96 if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph
)))
98 *(__be32
*)iph
|= htonl(INET_ECN_CE
<< 20);
102 static inline void IP6_ECN_clear(struct ipv6hdr
*iph
)
104 *(__be32
*)iph
&= ~htonl(INET_ECN_MASK
<< 20);
107 static inline void ipv6_copy_dscp(struct ipv6hdr
*outer
, struct ipv6hdr
*inner
)
109 u32 dscp
= ipv6_get_dsfield(outer
) & ~INET_ECN_MASK
;
110 ipv6_change_dsfield(inner
, INET_ECN_MASK
, dscp
);
113 static inline int INET_ECN_set_ce(struct sk_buff
*skb
)
115 switch (skb
->protocol
) {
116 case __constant_htons(ETH_P_IP
):
117 if (skb_network_header(skb
) + sizeof(struct iphdr
) <=
119 return IP_ECN_set_ce(ip_hdr(skb
));
122 case __constant_htons(ETH_P_IPV6
):
123 if (skb_network_header(skb
) + sizeof(struct ipv6hdr
) <=
125 return IP6_ECN_set_ce(ipv6_hdr(skb
));