Commit ffcacff8 authored by Poorva Sonparote's avatar Poorva Sonparote Committed by David S. Miller
Browse files

mptcp: Support for IP_TOS for MPTCP setsockopt() 

SOL_IP provides a way to configure network layer attributes in a
socket. This patch adds support for IP_TOS for setsockopt(.. ,SOL_IP, ..)

Support for SOL_IP is added in mptcp_setsockopt() and IP_TOS is handled in
a private function. The idea here is to take in the value passed for IP_TOS
and set it to the current subflow, open subflows as well new subflows that
might be created after the initial call to setsockopt(). This sync is done
using sync_socket_options(.., ssk) and setting the value of tos using
__ip_sock_set_tos(ssk,..).

The patch has been tested using the packetdrill script here -
https://github.com/multipath-tcp/mptcp_net-next/issues/220#issuecomment-947863717

Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/220


Signed-off-by: default avatarPoorva Sonparote <psonparo@redhat.com>
Signed-off-by: default avatarMat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 4f47d5d5

net/mptcp/sockopt.c

+40 −0
Original line number Diff line number Diff line
@@ -598,6 +598,42 @@ static int mptcp_setsockopt_sol_tcp_congestion(struct mptcp_sock *msk, sockptr_t 
	return ret;

}



static int mptcp_setsockopt_v4_set_tos(struct mptcp_sock *msk, int optname,

				       sockptr_t optval, unsigned int optlen)

{

	struct mptcp_subflow_context *subflow;

	struct sock *sk = (struct sock *)msk;

	int err, val;



	err = ip_setsockopt(sk, SOL_IP, optname, optval, optlen);



	if (err != 0)

		return err;



	lock_sock(sk);

	sockopt_seq_inc(msk);

	val = inet_sk(sk)->tos;

	mptcp_for_each_subflow(msk, subflow) {

		struct sock *ssk = mptcp_subflow_tcp_sock(subflow);



		__ip_sock_set_tos(ssk, val);

	}

	release_sock(sk);



	return err;

}



static int mptcp_setsockopt_v4(struct mptcp_sock *msk, int optname,

			       sockptr_t optval, unsigned int optlen)

{

	switch (optname) {

	case IP_TOS:

		return mptcp_setsockopt_v4_set_tos(msk, optname, optval, optlen);

	}



	return -EOPNOTSUPP;

}



static int mptcp_setsockopt_sol_tcp(struct mptcp_sock *msk, int optname,

				    sockptr_t optval, unsigned int optlen)

{
@@ -637,6 +673,9 @@ int mptcp_setsockopt(struct sock *sk, int level, int optname, 
	if (ssk)

		return tcp_setsockopt(ssk, level, optname, optval, optlen);



	if (level == SOL_IP)

		return mptcp_setsockopt_v4(msk, optname, optval, optlen);



	if (level == SOL_IPV6)

		return mptcp_setsockopt_v6(msk, optname, optval, optlen);
@@ -1003,6 +1042,7 @@ static void sync_socket_options(struct mptcp_sock *msk, struct sock *ssk) 
	ssk->sk_priority = sk->sk_priority;

	ssk->sk_bound_dev_if = sk->sk_bound_dev_if;

	ssk->sk_incoming_cpu = sk->sk_incoming_cpu;

	__ip_sock_set_tos(ssk, inet_sk(sk)->tos);



	if (sk->sk_userlocks & tx_rx_locks) {

		ssk->sk_userlocks |= sk->sk_userlocks & tx_rx_locks;