[v4,mptcp-next,2/5] mptcp: local addresses fullmesh

Commit Message

Geliang Tang July 26, 2021, 11:08 a.m. UTC

From: Geliang Tang <[e-mail]>

In mptcp_pm_nl_add_addr_received(), fill a temporary allocate array of
all local address corresponding to the fullmesh endpoint. If such array
is empty, keep the current behavior.

Elsewhere loop on such array and create a subflow for each local address
towards the given remote address

Suggested-by: Paolo Abeni <[e-mail]>
Signed-off-by: Geliang Tang <[e-mail]>
---
 net/mptcp/pm_netlink.c | 59 ++++++++++++++++++++++++++++++++++++++----
 1 file changed, 54 insertions(+), 5 deletions(-)

Patch

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 2a09d28d98be..10f09a96952b 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -540,13 +540,61 @@  static void mptcp_pm_nl_subflow_established(struct mptcp_sock *msk)
 	mptcp_pm_create_subflow_or_signal_addr(msk);
 }
 
+static unsigned int fill_local_addresses_vec(struct mptcp_sock *msk,
+					     struct mptcp_addr_info *remote,
+					     struct mptcp_pm_addr_entry *entries)
+{
+	struct mptcp_pm_addr_entry local, *entry;
+	struct sock *sk = (struct sock *)msk;
+	struct pm_nl_pernet *pernet;
+	unsigned int subflows_max;
+	int i = 0;
+
+	pernet = net_generic(sock_net(sk), pm_nl_pernet_id);
+	subflows_max = mptcp_pm_get_subflows_max(msk);
+
+	rcu_read_lock();
+	__mptcp_flush_join_list(msk);
+	list_for_each_entry_rcu(entry, &pernet->local_addr_list, list) {
+		if (!(entry->flags & MPTCP_PM_ADDR_FLAG_FULLMESH))
+			continue;
+
+		if (entry->addr.family != sk->sk_family) {
+#if IS_ENABLED(CONFIG_MPTCP_IPV6)
+			if ((entry->addr.family == AF_INET &&
+			     !ipv6_addr_v4mapped(&sk->sk_v6_daddr)) ||
+			    (sk->sk_family == AF_INET &&
+			     !ipv6_addr_v4mapped(&entry->addr.addr6)))
+#endif
+				continue;
+		}
+
+		if (!lookup_subflow_by_addrs(&msk->conn_list, &entry->addr, remote) &&
+		    msk->pm.subflows < subflows_max) {
+			msk->pm.subflows++;
+			entries[i++] = *entry;
+		}
+	}
+	rcu_read_unlock();
+
+	if (!i) {
+		memset(&local, 0, sizeof(local));
+		local.addr.family = remote->family;
+
+		entries[i++] = local;
+	}
+
+	return i;
+}
+
 static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 {
+	struct mptcp_pm_addr_entry entries[MPTCP_PM_ADDR_MAX];
 	struct sock *sk = (struct sock *)msk;
 	unsigned int add_addr_accept_max;
 	struct mptcp_addr_info remote;
-	struct mptcp_addr_info local;
 	unsigned int subflows_max;
+	int i, nr;
 
 	add_addr_accept_max = mptcp_pm_get_add_addr_accept_max(msk);
 	subflows_max = mptcp_pm_get_subflows_max(msk);
@@ -570,11 +618,12 @@  static void mptcp_pm_nl_add_addr_received(struct mptcp_sock *msk)
 	remote = msk->pm.remote;
 	if (!remote.port)
 		remote.port = sk->sk_dport;
-	memset(&local, 0, sizeof(local));
-	local.family = remote.family;
-
+	nr = fill_local_addresses_vec(msk, &remote, entries);
 	spin_unlock_bh(&msk->pm.lock);
-	__mptcp_subflow_connect(sk, &local, &remote, 0, 0);
+	for (i = 0; i < nr; i++) {
+		__mptcp_subflow_connect(sk, &entries[i].addr, &remote,
+					entries[i].flags, entries[i].ifindex);
+	}
 	spin_lock_bh(&msk->pm.lock);
 
 add_addr_echo: