[PATCH net 3/6] netfilter: conntrack: move synack init code to helper
From: Pablo Neira Ayuso <pablo@netfilter.org>
Date: 2022-02-04 15:19:21
Also in:
netfilter-devel
Subsystem:
netfilter, networking [general], the rest · Maintainers:
Pablo Neira Ayuso, Florian Westphal, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
From: Florian Westphal <fw@strlen.de> It seems more readable to use a common helper in the followup fix rather than copypaste or goto. No functional change intended. The function is only called for syn-ack or syn in repy direction in case of simultaneous open. Signed-off-by: Florian Westphal <fw@strlen.de> Acked-by: Jozsef Kadlecsik <redacted> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org> --- net/netfilter/nf_conntrack_proto_tcp.c | 47 ++++++++++++++++---------- 1 file changed, 29 insertions(+), 18 deletions(-)
diff --git a/net/netfilter/nf_conntrack_proto_tcp.c b/net/netfilter/nf_conntrack_proto_tcp.c
index af5115e127cf..88c89e97d8a2 100644
--- a/net/netfilter/nf_conntrack_proto_tcp.c
+++ b/net/netfilter/nf_conntrack_proto_tcp.c@@ -446,6 +446,32 @@ static void tcp_sack(const struct sk_buff *skb, unsigned int dataoff, } } +static void tcp_init_sender(struct ip_ct_tcp_state *sender, + struct ip_ct_tcp_state *receiver, + const struct sk_buff *skb, + unsigned int dataoff, + const struct tcphdr *tcph, + u32 end, u32 win) +{ + /* SYN-ACK in reply to a SYN + * or SYN from reply direction in simultaneous open. + */ + sender->td_end = + sender->td_maxend = end; + sender->td_maxwin = (win == 0 ? 1 : win); + + tcp_options(skb, dataoff, tcph, sender); + /* RFC 1323: + * Both sides must send the Window Scale option + * to enable window scaling in either direction. + */ + if (!(sender->flags & IP_CT_TCP_FLAG_WINDOW_SCALE && + receiver->flags & IP_CT_TCP_FLAG_WINDOW_SCALE)) { + sender->td_scale = 0; + receiver->td_scale = 0; + } +} + static bool tcp_in_window(struct nf_conn *ct, enum ip_conntrack_dir dir, unsigned int index,
@@ -499,24 +525,9 @@ static bool tcp_in_window(struct nf_conn *ct, * Initialize sender data. */ if (tcph->syn) { - /* - * SYN-ACK in reply to a SYN - * or SYN from reply direction in simultaneous open. - */ - sender->td_end = - sender->td_maxend = end; - sender->td_maxwin = (win == 0 ? 1 : win); - - tcp_options(skb, dataoff, tcph, sender); - /* - * RFC 1323: - * Both sides must send the Window Scale option - * to enable window scaling in either direction. - */ - if (!(sender->flags & IP_CT_TCP_FLAG_WINDOW_SCALE - && receiver->flags & IP_CT_TCP_FLAG_WINDOW_SCALE)) - sender->td_scale = - receiver->td_scale = 0; + tcp_init_sender(sender, receiver, + skb, dataoff, tcph, + end, win); if (!tcph->ack) /* Simultaneous open */ return true;
--
2.30.2