tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1#ifndef _INET_ECN_H_
2#define _INET_ECN_H_
3
4#include <linux/ip.h>
5#include <net/dsfield.h>
6
7enum {
8 INET_ECN_NOT_ECT = 0,
9 INET_ECN_ECT_1 = 1,
10 INET_ECN_ECT_0 = 2,
11 INET_ECN_CE = 3,
12 INET_ECN_MASK = 3,
13};
14
15static inline int INET_ECN_is_ce(__u8 dsfield)
16{
17 return (dsfield & INET_ECN_MASK) == INET_ECN_CE;
18}
19
20static inline int INET_ECN_is_not_ect(__u8 dsfield)
21{
22 return (dsfield & INET_ECN_MASK) == INET_ECN_NOT_ECT;
23}
24
25static inline int INET_ECN_is_capable(__u8 dsfield)
26{
27 return (dsfield & INET_ECN_ECT_0);
28}
29
30static inline __u8 INET_ECN_encapsulate(__u8 outer, __u8 inner)
31{
32 outer &= ~INET_ECN_MASK;
33 outer |= !INET_ECN_is_ce(inner) ? (inner & INET_ECN_MASK) :
34 INET_ECN_ECT_0;
35 return outer;
36}
37
38#define INET_ECN_xmit(sk) do { inet_sk(sk)->tos |= INET_ECN_ECT_0; } while (0)
39#define INET_ECN_dontxmit(sk) \
40 do { inet_sk(sk)->tos &= ~INET_ECN_MASK; } while (0)
41
42#define IP6_ECN_flow_init(label) do { \
43 (label) &= ~htonl(INET_ECN_MASK << 20); \
44 } while (0)
45
46#define IP6_ECN_flow_xmit(sk, label) do { \
47 if (INET_ECN_is_capable(inet_sk(sk)->tos)) \
48 (label) |= __constant_htons(INET_ECN_ECT_0 << 4); \
49 } while (0)
50
51static inline void IP_ECN_set_ce(struct iphdr *iph)
52{
53 u32 check = iph->check;
54 u32 ecn = (iph->tos + 1) & INET_ECN_MASK;
55
56 /*
57 * After the last operation we have (in binary):
58 * INET_ECN_NOT_ECT => 01
59 * INET_ECN_ECT_1 => 10
60 * INET_ECN_ECT_0 => 11
61 * INET_ECN_CE => 00
62 */
63 if (!(ecn & 2))
64 return;
65
66 /*
67 * The following gives us:
68 * INET_ECN_ECT_1 => check += htons(0xFFFD)
69 * INET_ECN_ECT_0 => check += htons(0xFFFE)
70 */
71 check += htons(0xFFFB) + htons(ecn);
72
73 iph->check = check + (check>=0xFFFF);
74 iph->tos |= INET_ECN_CE;
75}
76
77static inline void IP_ECN_clear(struct iphdr *iph)
78{
79 iph->tos &= ~INET_ECN_MASK;
80}
81
82static inline void ipv4_copy_dscp(struct iphdr *outer, struct iphdr *inner)
83{
84 u32 dscp = ipv4_get_dsfield(outer) & ~INET_ECN_MASK;
85 ipv4_change_dsfield(inner, INET_ECN_MASK, dscp);
86}
87
88struct ipv6hdr;
89
90static inline void IP6_ECN_set_ce(struct ipv6hdr *iph)
91{
92 if (INET_ECN_is_not_ect(ipv6_get_dsfield(iph)))
93 return;
94 *(u32*)iph |= htonl(INET_ECN_CE << 20);
95}
96
97static inline void IP6_ECN_clear(struct ipv6hdr *iph)
98{
99 *(u32*)iph &= ~htonl(INET_ECN_MASK << 20);
100}
101
102static inline void ipv6_copy_dscp(struct ipv6hdr *outer, struct ipv6hdr *inner)
103{
104 u32 dscp = ipv6_get_dsfield(outer) & ~INET_ECN_MASK;
105 ipv6_change_dsfield(inner, INET_ECN_MASK, dscp);
106}
107
108#endif