diff options
Diffstat (limited to '')
| -rw-r--r-- | net/netfilter/nf_conntrack_proto_tcp.c | 40 |
1 files changed, 15 insertions, 25 deletions
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c index 626b0011dd89..6fccdcf43e08 100644 --- a/net/netfilter/nf_conntrack_proto_tcp.c +++ b/net/netfilter/nf_conntrack_proto_tcp.c @@ -60,12 +60,9 @@ static DEFINE_RWLOCK(tcp_lock); If it's non-zero, we mark only out of window RST segments as INVALID. */ int nf_ct_tcp_be_liberal __read_mostly = 0; -/* When connection is picked up from the middle, how many packets are required - to pass in each direction when we assume we are in sync - if any side uses - window scaling, we lost the game. - If it is set to zero, we disable picking up already established +/* If it is set to zero, we disable picking up already established connections. */ -int nf_ct_tcp_loose __read_mostly = 3; +int nf_ct_tcp_loose __read_mostly = 1; /* Max number of the retransmitted packets without receiving an (acceptable) ACK from the destination. If this number is reached, a shorter timer @@ -650,11 +647,10 @@ static int tcp_in_window(struct ip_ct_tcp *state, before(sack, receiver->td_end + 1), after(ack, receiver->td_end - MAXACKWINDOW(sender))); - if (sender->loose || receiver->loose || - (before(seq, sender->td_maxend + 1) && - after(end, sender->td_end - receiver->td_maxwin - 1) && - before(sack, receiver->td_end + 1) && - after(ack, receiver->td_end - MAXACKWINDOW(sender)))) { + if (before(seq, sender->td_maxend + 1) && + after(end, sender->td_end - receiver->td_maxwin - 1) && + before(sack, receiver->td_end + 1) && + after(ack, receiver->td_end - MAXACKWINDOW(sender))) { /* * Take into account window scaling (RFC 1323). */ @@ -699,15 +695,13 @@ static int tcp_in_window(struct ip_ct_tcp *state, state->retrans = 0; } } - /* - * Close the window of disabled window tracking :-) - */ - if (sender->loose) - sender->loose--; - res = 1; } else { - if (LOG_INVALID(IPPROTO_TCP)) + res = 0; + if (sender->flags & IP_CT_TCP_FLAG_BE_LIBERAL || + nf_ct_tcp_be_liberal) + res = 1; + if (!res && LOG_INVALID(IPPROTO_TCP)) nf_log_packet(pf, 0, skb, NULL, NULL, NULL, "nf_ct_tcp: %s ", before(seq, sender->td_maxend + 1) ? @@ -718,8 +712,6 @@ static int tcp_in_window(struct ip_ct_tcp *state, : "ACK is over the upper bound (ACKed data not seen yet)" : "SEQ is under the lower bound (already ACKed data retransmitted)" : "SEQ is over the upper bound (over the window of the receiver)"); - - res = nf_ct_tcp_be_liberal; } DEBUGP("tcp_in_window: res=%i sender end=%u maxend=%u maxwin=%u " @@ -1063,8 +1055,6 @@ static int tcp_new(struct nf_conn *conntrack, tcp_options(skb, dataoff, th, &conntrack->proto.tcp.seen[0]); conntrack->proto.tcp.seen[1].flags = 0; - conntrack->proto.tcp.seen[0].loose = - conntrack->proto.tcp.seen[1].loose = 0; } else if (nf_ct_tcp_loose == 0) { /* Don't try to pick up connections. */ return 0; @@ -1085,11 +1075,11 @@ static int tcp_new(struct nf_conn *conntrack, conntrack->proto.tcp.seen[0].td_maxwin; conntrack->proto.tcp.seen[0].td_scale = 0; - /* We assume SACK. Should we assume window scaling too? */ + /* We assume SACK and liberal window checking to handle + * window scaling */ conntrack->proto.tcp.seen[0].flags = - conntrack->proto.tcp.seen[1].flags = IP_CT_TCP_FLAG_SACK_PERM; - conntrack->proto.tcp.seen[0].loose = - conntrack->proto.tcp.seen[1].loose = nf_ct_tcp_loose; + conntrack->proto.tcp.seen[1].flags = IP_CT_TCP_FLAG_SACK_PERM | + IP_CT_TCP_FLAG_BE_LIBERAL; } conntrack->proto.tcp.seen[1].td_end = 0; |