diff options
Diffstat (limited to 'net/ipv4/tcp_output.c')
| -rw-r--r-- | net/ipv4/tcp_output.c | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index b11025e8a49..3abe22e4b57 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -269,6 +269,56 @@ static u16 tcp_select_window(struct sock *sk) return new_win; } +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 sk_buff *skb) +{ + struct tcp_sock *tp = tcp_sk(sk); + + 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 sk_buff *skb, + int tcp_header_len) +{ + struct tcp_sock *tp = tcp_sk(sk); + + 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; + tcp_hdr(skb)->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) + tcp_hdr(skb)->ece = 1; + } +} + static void tcp_build_and_update_options(__be32 *ptr, struct tcp_sock *tp, __u32 tstamp, __u8 **md5_hash) { |