1 #ifndef _NET_TCP_ECN_H_
2 #define _NET_TCP_ECN_H_ 1
4 #include <net/inet_ecn.h>
6 #define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH))
9 #define TCP_ECN_QUEUE_CWR 2
10 #define TCP_ECN_DEMAND_CWR 4
12 static __inline__ void
13 TCP_ECN_queue_cwr(struct tcp_opt *tp)
15 if (tp->ecn_flags&TCP_ECN_OK)
16 tp->ecn_flags |= TCP_ECN_QUEUE_CWR;
20 /* Output functions */
22 static __inline__ void
23 TCP_ECN_send_synack(struct tcp_opt *tp, struct sk_buff *skb)
25 TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR;
26 if (!(tp->ecn_flags&TCP_ECN_OK))
27 TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE;
30 static __inline__ void
31 TCP_ECN_send_syn(struct sock *sk, struct tcp_opt *tp, struct sk_buff *skb)
34 if (sysctl_tcp_ecn && !(sk->sk_route_caps & NETIF_F_TSO)) {
35 TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR;
36 tp->ecn_flags = TCP_ECN_OK;
37 sk->sk_no_largesend = 1;
41 static __inline__ void
42 TCP_ECN_make_synack(struct open_request *req, struct tcphdr *th)
48 static __inline__ void
49 TCP_ECN_send(struct sock *sk, struct tcp_opt *tp, struct sk_buff *skb, int tcp_header_len)
51 if (tp->ecn_flags & TCP_ECN_OK) {
52 /* Not-retransmitted data segment: set ECT and inject CWR. */
53 if (skb->len != tcp_header_len &&
54 !before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) {
56 if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
57 tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
61 /* ACK or retransmitted segment: clear ECT|CE */
62 INET_ECN_dontxmit(sk);
64 if (tp->ecn_flags & TCP_ECN_DEMAND_CWR)
71 static __inline__ void
72 TCP_ECN_accept_cwr(struct tcp_opt *tp, struct sk_buff *skb)
75 tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
78 static __inline__ void
79 TCP_ECN_withdraw_cwr(struct tcp_opt *tp)
81 tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
84 static __inline__ void
85 TCP_ECN_check_ce(struct tcp_opt *tp, struct sk_buff *skb)
87 if (tp->ecn_flags&TCP_ECN_OK) {
88 if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags))
89 tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
90 /* Funny extension: if ECT is not set on a segment,
91 * it is surely retransmit. It is not in ECN RFC,
92 * but Linux follows this rule. */
93 else if (!INET_ECN_is_capable((TCP_SKB_CB(skb)->flags)))
94 tcp_enter_quickack_mode(tp);
98 static __inline__ void
99 TCP_ECN_rcv_synack(struct tcp_opt *tp, struct tcphdr *th)
101 if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || th->cwr))
102 tp->ecn_flags &= ~TCP_ECN_OK;
105 static __inline__ void
106 TCP_ECN_rcv_syn(struct tcp_opt *tp, struct tcphdr *th)
108 if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || !th->cwr))
109 tp->ecn_flags &= ~TCP_ECN_OK;
112 static __inline__ int
113 TCP_ECN_rcv_ecn_echo(struct tcp_opt *tp, struct tcphdr *th)
115 if (th->ece && !th->syn && (tp->ecn_flags&TCP_ECN_OK))
120 static __inline__ void
121 TCP_ECN_openreq_child(struct tcp_opt *tp, struct open_request *req)
123 tp->ecn_flags = req->ecn_ok ? TCP_ECN_OK : 0;
126 static __inline__ void
127 TCP_ECN_create_request(struct open_request *req, struct tcphdr *th)
129 if (sysctl_tcp_ecn && th->ece && th->cwr)