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 tcp_opt *tp, struct sk_buff *skb)
35 TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR;
36 tp->ecn_flags = TCP_ECN_OK;
40 static __inline__ void
41 TCP_ECN_make_synack(struct open_request *req, struct tcphdr *th)
47 static __inline__ void
48 TCP_ECN_send(struct sock *sk, struct tcp_opt *tp, struct sk_buff *skb, int tcp_header_len)
50 if (tp->ecn_flags & TCP_ECN_OK) {
51 /* Not-retransmitted data segment: set ECT and inject CWR. */
52 if (skb->len != tcp_header_len &&
53 !before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) {
55 if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) {
56 tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR;
60 /* ACK or retransmitted segment: clear ECT|CE */
61 INET_ECN_dontxmit(sk);
63 if (tp->ecn_flags & TCP_ECN_DEMAND_CWR)
70 static __inline__ void
71 TCP_ECN_accept_cwr(struct tcp_opt *tp, struct sk_buff *skb)
74 tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
77 static __inline__ void
78 TCP_ECN_withdraw_cwr(struct tcp_opt *tp)
80 tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR;
83 static __inline__ void
84 TCP_ECN_check_ce(struct tcp_opt *tp, struct sk_buff *skb)
86 if (tp->ecn_flags&TCP_ECN_OK) {
87 if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags))
88 tp->ecn_flags |= TCP_ECN_DEMAND_CWR;
89 /* Funny extension: if ECT is not set on a segment,
90 * it is surely retransmit. It is not in ECN RFC,
91 * but Linux follows this rule. */
92 else if (!INET_ECN_is_capable((TCP_SKB_CB(skb)->flags)))
93 tcp_enter_quickack_mode(tp);
97 static __inline__ void
98 TCP_ECN_rcv_synack(struct tcp_opt *tp, struct tcphdr *th)
100 if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || th->cwr))
101 tp->ecn_flags &= ~TCP_ECN_OK;
104 static __inline__ void
105 TCP_ECN_rcv_syn(struct tcp_opt *tp, struct tcphdr *th)
107 if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || !th->cwr))
108 tp->ecn_flags &= ~TCP_ECN_OK;
111 static __inline__ int
112 TCP_ECN_rcv_ecn_echo(struct tcp_opt *tp, struct tcphdr *th)
114 if (th->ece && !th->syn && (tp->ecn_flags&TCP_ECN_OK))
119 static __inline__ void
120 TCP_ECN_openreq_child(struct tcp_opt *tp, struct open_request *req)
122 tp->ecn_flags = req->ecn_ok ? TCP_ECN_OK : 0;
125 static __inline__ void
126 TCP_ECN_create_request(struct open_request *req, struct tcphdr *th)
128 if (sysctl_tcp_ecn && th->ece && th->cwr)