diff options
| author | Patrick McHardy <kaber@trash.net> | 2008-07-31 11:38:01 +0400 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2008-07-31 11:38:01 +0400 |
| commit | ae375044d31075a31de5a839e07ded7f67b660aa (patch) | |
| tree | 13f49a97aa48fa8f19cbe7055e0b5e4df3abc462 | |
| parent | a97a6f10771b90235b33c13a6db9279237a08422 (diff) | |
| download | linux-ae375044d31075a31de5a839e07ded7f67b660aa.tar.xz | |
netfilter: nf_conntrack_tcp: decrease timeouts while data in unacknowledged
In order to time out dead connections quicker, keep track of outstanding data
and cap the timeout.
Suggested by Herbert Xu.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/netfilter/nf_conntrack_tcp.h | 3 | ||||
| -rw-r--r-- | net/netfilter/nf_conntrack_proto_tcp.c | 29 |
2 files changed, 27 insertions, 5 deletions
diff --git a/include/linux/netfilter/nf_conntrack_tcp.h b/include/linux/netfilter/nf_conntrack_tcp.h index 22ce29995f13..a049df4f2236 100644 --- a/include/linux/netfilter/nf_conntrack_tcp.h +++ b/include/linux/netfilter/nf_conntrack_tcp.h @@ -30,6 +30,9 @@ enum tcp_conntrack { /* Be liberal in window checking */ #define IP_CT_TCP_FLAG_BE_LIBERAL 0x08 +/* Has unacknowledged data */ +#define IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED 0x10 + struct nf_ct_tcp_flags { u_int8_t flags; u_int8_t mask; diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index 420a10d8eb1e..6f61261888ef 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -67,7 +67,8 @@ static const char *const tcp_conntrack_names[] = { /* RFC1122 says the R2 limit should be at least 100 seconds. Linux uses 15 packets as limit, which corresponds to ~13-30min depending on RTO. */ -static unsigned int nf_ct_tcp_timeout_max_retrans __read_mostly = 5 MINS; +static unsigned int nf_ct_tcp_timeout_max_retrans __read_mostly = 5 MINS; +static unsigned int nf_ct_tcp_timeout_unacknowledged __read_mostly = 5 MINS; static unsigned int tcp_timeouts[TCP_CONNTRACK_MAX] __read_mostly = { [TCP_CONNTRACK_SYN_SENT] = 2 MINS, @@ -625,8 +626,10 @@ static bool tcp_in_window(const struct nf_conn *ct, swin = win + (sack - ack); if (sender->td_maxwin < swin) sender->td_maxwin = swin; - if (after(end, sender->td_end)) + if (after(end, sender->td_end)) { sender->td_end = end; + sender->flags |= IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED; + } /* * Update receiver data. */ @@ -637,6 +640,8 @@ static bool tcp_in_window(const struct nf_conn *ct, if (win == 0) receiver->td_maxend++; } + if (ack == receiver->td_end) + receiver->flags &= ~IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED; /* * Check retransmissions. @@ -951,9 +956,16 @@ static int tcp_packet(struct nf_conn *ct, if (old_state != new_state && new_state == TCP_CONNTRACK_FIN_WAIT) ct->proto.tcp.seen[dir].flags |= IP_CT_TCP_FLAG_CLOSE_INIT; - timeout = ct->proto.tcp.retrans >= nf_ct_tcp_max_retrans - && tcp_timeouts[new_state] > nf_ct_tcp_timeout_max_retrans - ? nf_ct_tcp_timeout_max_retrans : tcp_timeouts[new_state]; + + if (ct->proto.tcp.retrans >= nf_ct_tcp_max_retrans && + tcp_timeouts[new_state] > nf_ct_tcp_timeout_max_retrans) + timeout = nf_ct_tcp_timeout_max_retrans; + else if ((ct->proto.tcp.seen[0].flags | ct->proto.tcp.seen[1].flags) & + IP_CT_TCP_FLAG_DATA_UNACKNOWLEDGED && + tcp_timeouts[new_state] > nf_ct_tcp_timeout_unacknowledged) + timeout = nf_ct_tcp_timeout_unacknowledged; + else + timeout = tcp_timeouts[new_state]; write_unlock_bh(&tcp_lock); nf_conntrack_event_cache(IPCT_PROTOINFO_VOLATILE, skb); @@ -1236,6 +1248,13 @@ static struct ctl_table tcp_sysctl_table[] = { .proc_handler = &proc_dointvec_jiffies, }, { + .procname = "nf_conntrack_tcp_timeout_unacknowledged", + .data = &nf_ct_tcp_timeout_unacknowledged, + .maxlen = sizeof(unsigned int), + .mode = 0644, + .proc_handler = &proc_dointvec_jiffies, + }, + { .ctl_name = NET_NF_CONNTRACK_TCP_LOOSE, .procname = "nf_conntrack_tcp_loose", .data = &nf_ct_tcp_loose, |