#ifndef _NET_TCP_ECN_H_ #define _NET_TCP_ECN_H_ 1 #include <net/inet_ecn.h> #include <net/request_sock.h> #define TCP_HP_BITS (~(TCP_RESERVED_BITS|TCP_FLAG_PSH)) #define TCP_ECN_OK 1 #define TCP_ECN_QUEUE_CWR 2 #define TCP_ECN_DEMAND_CWR 4 static inline void TCP_ECN_queue_cwr(struct tcp_sock *tp) { if (tp->ecn_flags&TCP_ECN_OK) tp->ecn_flags |= TCP_ECN_QUEUE_CWR; } /* Output functions */ static inline void TCP_ECN_send_synack(struct tcp_sock *tp, struct sk_buff *skb) { TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_CWR; if (!(tp->ecn_flags&TCP_ECN_OK)) TCP_SKB_CB(skb)->flags &= ~TCPCB_FLAG_ECE; } static inline void TCP_ECN_send_syn(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb) { tp->ecn_flags = 0; if (sysctl_tcp_ecn) { TCP_SKB_CB(skb)->flags |= TCPCB_FLAG_ECE|TCPCB_FLAG_CWR; tp->ecn_flags = TCP_ECN_OK; } } static __inline__ void TCP_ECN_make_synack(struct request_sock *req, struct tcphdr *th) { if (inet_rsk(req)->ecn_ok) th->ece = 1; } static inline void TCP_ECN_send(struct sock *sk, struct tcp_sock *tp, struct sk_buff *skb, int tcp_header_len) { if (tp->ecn_flags & TCP_ECN_OK) { /* Not-retransmitted data segment: set ECT and inject CWR. */ if (skb->len != tcp_header_len && !before(TCP_SKB_CB(skb)->seq, tp->snd_nxt)) { INET_ECN_xmit(sk); if (tp->ecn_flags&TCP_ECN_QUEUE_CWR) { tp->ecn_flags &= ~TCP_ECN_QUEUE_CWR; skb->h.th->cwr = 1; skb_shinfo(skb)->gso_type |= SKB_GSO_TCP_ECN; } } else { /* ACK or retransmitted segment: clear ECT|CE */ INET_ECN_dontxmit(sk); } if (tp->ecn_flags & TCP_ECN_DEMAND_CWR) skb->h.th->ece = 1; } } /* Input functions */ static inline void TCP_ECN_accept_cwr(struct tcp_sock *tp, struct sk_buff *skb) { if (skb->h.th->cwr) tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR; } static inline void TCP_ECN_withdraw_cwr(struct tcp_sock *tp) { tp->ecn_flags &= ~TCP_ECN_DEMAND_CWR; } static inline void TCP_ECN_check_ce(struct tcp_sock *tp, struct sk_buff *skb) { if (tp->ecn_flags&TCP_ECN_OK) { if (INET_ECN_is_ce(TCP_SKB_CB(skb)->flags)) tp->ecn_flags |= TCP_ECN_DEMAND_CWR; /* Funny extension: if ECT is not set on a segment, * it is surely retransmit. It is not in ECN RFC, * but Linux follows this rule. */ else if (INET_ECN_is_not_ect((TCP_SKB_CB(skb)->flags))) tcp_enter_quickack_mode((struct sock *)tp); } } static inline void TCP_ECN_rcv_synack(struct tcp_sock *tp, struct tcphdr *th) { if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || th->cwr)) tp->ecn_flags &= ~TCP_ECN_OK; } static inline void TCP_ECN_rcv_syn(struct tcp_sock *tp, struct tcphdr *th) { if ((tp->ecn_flags&TCP_ECN_OK) && (!th->ece || !th->cwr)) tp->ecn_flags &= ~TCP_ECN_OK; } static inline int TCP_ECN_rcv_ecn_echo(struct tcp_sock *tp, struct tcphdr *th) { if (th->ece && !th->syn && (tp->ecn_flags&TCP_ECN_OK)) return 1; return 0; } static inline void TCP_ECN_openreq_child(struct tcp_sock *tp, struct request_sock *req) { tp->ecn_flags = inet_rsk(req)->ecn_ok ? TCP_ECN_OK : 0; } static __inline__ void TCP_ECN_create_request(struct request_sock *req, struct tcphdr *th) { if (sysctl_tcp_ecn && th->ece && th->cwr) inet_rsk(req)->ecn_ok = 1; } #endif