mptcp: Add mptcp_close_state() helper

This will be used to transition to the appropriate state on close and
determine if a DATA_FIN needs to be sent for that state transition.

Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Mat Martineau 2020-07-28 15:12:04 -07:00 committed by David S. Miller
parent 3721b9b646
commit 6920b85158
1 changed files with 27 additions and 0 deletions

View File

@ -1498,6 +1498,33 @@ static void mptcp_subflow_shutdown(struct sock *ssk, int how)
release_sock(ssk);
}
static const unsigned char new_state[16] = {
/* current state: new state: action: */
[0 /* (Invalid) */] = TCP_CLOSE,
[TCP_ESTABLISHED] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
[TCP_SYN_SENT] = TCP_CLOSE,
[TCP_SYN_RECV] = TCP_FIN_WAIT1 | TCP_ACTION_FIN,
[TCP_FIN_WAIT1] = TCP_FIN_WAIT1,
[TCP_FIN_WAIT2] = TCP_FIN_WAIT2,
[TCP_TIME_WAIT] = TCP_CLOSE, /* should not happen ! */
[TCP_CLOSE] = TCP_CLOSE,
[TCP_CLOSE_WAIT] = TCP_LAST_ACK | TCP_ACTION_FIN,
[TCP_LAST_ACK] = TCP_LAST_ACK,
[TCP_LISTEN] = TCP_CLOSE,
[TCP_CLOSING] = TCP_CLOSING,
[TCP_NEW_SYN_RECV] = TCP_CLOSE, /* should not happen ! */
};
static int mptcp_close_state(struct sock *sk)
{
int next = (int)new_state[sk->sk_state];
int ns = next & TCP_STATE_MASK;
inet_sk_state_store(sk, ns);
return next & TCP_ACTION_FIN;
}
static void mptcp_close(struct sock *sk, long timeout)
{
struct mptcp_subflow_context *subflow, *tmp;