Commit cc4f9d62 authored by Florian Westphal's avatar Florian Westphal Committed by Pablo Neira Ayuso
Browse files

netfilter: conntrack: move synack init code to helper 



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: default avatarFlorian Westphal <fw@strlen.de>
Acked-by: default avatarJozsef Kadlecsik <kadlec@netfilter.org>
Signed-off-by: default avatarPablo Neira Ayuso <pablo@netfilter.org>
parent a9e8503d

net/netfilter/nf_conntrack_proto_tcp.c

+29 −18
Original line number Diff line number Diff line
@@ -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;