From 172d69e63c7f1e8300d0e1c1bbd8eb0f630faa15 Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Mon, 21 Jun 2010 11:48:45 +0000 Subject: syncookies: add support for ECN Allows use of ECN when syncookies are in effect by encoding ecn_ok into the syn-ack tcp timestamp. While at it, remove a uneeded #ifdef CONFIG_SYN_COOKIES. With CONFIG_SYN_COOKIES=nm want_cookie is ifdef'd to 0 and gcc removes the "if (0)". Signed-off-by: Florian Westphal Signed-off-by: David S. Miller --- net/ipv6/syncookies.c | 5 +++-- net/ipv6/tcp_ipv6.c | 2 +- 2 files changed, 4 insertions(+), 3 deletions(-) (limited to 'net/ipv6') diff --git a/net/ipv6/syncookies.c b/net/ipv6/syncookies.c index 84d818cfae17..09fd34f0dbf2 100644 --- a/net/ipv6/syncookies.c +++ b/net/ipv6/syncookies.c @@ -164,6 +164,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) int mss; struct dst_entry *dst; __u8 rcv_wscale; + bool ecn_ok; if (!sysctl_tcp_syncookies || !th->ack || th->rst) goto out; @@ -180,7 +181,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) memset(&tcp_opt, 0, sizeof(tcp_opt)); tcp_parse_options(skb, &tcp_opt, &hash_location, 0); - if (!cookie_check_timestamp(&tcp_opt)) + if (!cookie_check_timestamp(&tcp_opt, &ecn_ok)) goto out; ret = NULL; @@ -215,7 +216,7 @@ struct sock *cookie_v6_check(struct sock *sk, struct sk_buff *skb) req->expires = 0UL; req->retrans = 0; - ireq->ecn_ok = 0; + ireq->ecn_ok = ecn_ok; ireq->snd_wscale = tcp_opt.snd_wscale; ireq->sack_ok = tcp_opt.sack_ok; ireq->wscale_ok = tcp_opt.wscale_ok; diff --git a/net/ipv6/tcp_ipv6.c b/net/ipv6/tcp_ipv6.c index f87534569366..5ebc27ecebdc 100644 --- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -1269,7 +1269,7 @@ static int tcp_v6_conn_request(struct sock *sk, struct sk_buff *skb) treq = inet6_rsk(req); ipv6_addr_copy(&treq->rmt_addr, &ipv6_hdr(skb)->saddr); ipv6_addr_copy(&treq->loc_addr, &ipv6_hdr(skb)->daddr); - if (!want_cookie) + if (!want_cookie || tmp_opt.tstamp_ok) TCP_ECN_create_request(req, tcp_hdr(skb)); if (!isn) { -- cgit v1.2.3