From dc87efdb1a5cd46134a9d490480160e303bc6eef Mon Sep 17 00:00:00 2001 From: Florian Westphal Date: Thu, 1 Apr 2021 16:19:44 -0700 Subject: mptcp: add mptcp reset option support The MPTCP reset option allows to carry a mptcp-specific error code that provides more information on the nature of a connection reset. Reset option data received gets stored in the subflow context so it can be sent to userspace via the 'subflow closed' netlink event. When a subflow is closed, the desired error code that should be sent to the peer is also placed in the subflow context structure. If a reset is sent before subflow establishment could complete, e.g. on HMAC failure during an MP_JOIN operation, the mptcp skb extension is used to store the reset information. Signed-off-by: Florian Westphal Signed-off-by: Mat Martineau Signed-off-by: David S. Miller --- net/mptcp/pm_netlink.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) (limited to 'net/mptcp/pm_netlink.c') diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c index cadafafa1049..51be6c34b339 100644 --- a/net/mptcp/pm_netlink.c +++ b/net/mptcp/pm_netlink.c @@ -1687,9 +1687,21 @@ static int mptcp_event_sub_closed(struct sk_buff *skb, const struct mptcp_sock *msk, const struct sock *ssk) { + const struct mptcp_subflow_context *sf; + if (mptcp_event_put_token_and_ssk(skb, msk, ssk)) return -EMSGSIZE; + sf = mptcp_subflow_ctx(ssk); + if (!sf->reset_seen) + return 0; + + if (nla_put_u32(skb, MPTCP_ATTR_RESET_REASON, sf->reset_reason)) + return -EMSGSIZE; + + if (nla_put_u32(skb, MPTCP_ATTR_RESET_FLAGS, sf->reset_transient)) + return -EMSGSIZE; + return 0; } -- cgit v1.2.3