mptcp: consolidate synack processing.
Currently the MPTCP code uses 2 hooks to process syn-ack
packets, mptcp_rcv_synsent() and the sk_rx_dst_set()
callback.
We can drop the first, moving the relevant code into the
latter, reducing the hooking into the TCP code. This is
also needed by the next patch.
v1 -> v2:
- use local tcp sock ptr instead of casting the sk variable
several times - DaveM
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/mptcp/subflow.c b/net/mptcp/subflow.c
index 71256f0..84f6408 100644
--- a/net/mptcp/subflow.c
+++ b/net/mptcp/subflow.c
@@ -222,6 +222,7 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
{
struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(sk);
struct sock *parent = subflow->conn;
+ struct tcp_sock *tp = tcp_sk(sk);
subflow->icsk_af_ops->sk_rx_dst_set(sk, skb);
@@ -230,14 +231,35 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
parent->sk_state_change(parent);
}
- if (subflow->conn_finished || !tcp_sk(sk)->is_mptcp)
+ /* be sure no special action on any packet other than syn-ack */
+ if (subflow->conn_finished)
+ return;
+
+ subflow->conn_finished = 1;
+
+ if (subflow->request_mptcp && tp->rx_opt.mptcp.mp_capable) {
+ subflow->mp_capable = 1;
+ subflow->can_ack = 1;
+ subflow->remote_key = tp->rx_opt.mptcp.sndr_key;
+ pr_debug("subflow=%p, remote_key=%llu", subflow,
+ subflow->remote_key);
+ } else if (subflow->request_join && tp->rx_opt.mptcp.mp_join) {
+ subflow->mp_join = 1;
+ subflow->thmac = tp->rx_opt.mptcp.thmac;
+ subflow->remote_nonce = tp->rx_opt.mptcp.nonce;
+ pr_debug("subflow=%p, thmac=%llu, remote_nonce=%u", subflow,
+ subflow->thmac, subflow->remote_nonce);
+ } else if (subflow->request_mptcp) {
+ tp->is_mptcp = 0;
+ }
+
+ if (!tp->is_mptcp)
return;
if (subflow->mp_capable) {
pr_debug("subflow=%p, remote_key=%llu", mptcp_subflow_ctx(sk),
subflow->remote_key);
mptcp_finish_connect(sk);
- subflow->conn_finished = 1;
if (skb) {
pr_debug("synack seq=%u", TCP_SKB_CB(skb)->seq);
@@ -264,7 +286,6 @@ static void subflow_finish_connect(struct sock *sk, const struct sk_buff *skb)
if (!mptcp_finish_join(sk))
goto do_reset;
- subflow->conn_finished = 1;
MPTCP_INC_STATS(sock_net(sk), MPTCP_MIB_JOINSYNACKRX);
} else {
do_reset: