diff mbox series

[net-next,2/5] mptcp: pm nl: support IPv4 mapped in v6 addresses

Message ID 20210125185904.6997-3-mathew.j.martineau@linux.intel.com (mailing list archive)
State Accepted
Commit 7b9b0f7e1230adde95be4958469d60c6fc06bc36
Delegated to: Netdev Maintainers
Headers show
Series MPTCP: IPv4-mapped IPv6 addressing for subflows | expand

Commit Message

Mat Martineau Jan. 25, 2021, 6:59 p.m. UTC 
From: Matthieu Baerts <matthieu.baerts@tessares.net>

On one side, we can allow the creation of subflows between v4 mapped in
v6 and v4 addresses. For that we look for v4mapped addresses between the
local address we want to select and the remote one.

On the other side, we also properly deal with received v4mapped
addresses, either announced ones or set via Netlink.

Fixes: 01cacb00b35c ("mptcp: add netlink-based PM")
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/122
Suggested-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Co-developed-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Geliang Tang <geliangtang@gmail.com>
Signed-off-by: Matthieu Baerts <matthieu.baerts@tessares.net>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
---
 net/mptcp/pm_netlink.c | 33 ++++++++++++++++++++++++---------
 1 file changed, 24 insertions(+), 9 deletions(-)
diff mbox series

Patch

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 9b1f6298bbdb..f0afff6ba015 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -60,15 +60,20 @@  static bool addresses_equal(const struct mptcp_addr_info *a,
 {
 	bool addr_equals = false;
 
-	if (a->family != b->family)
-		return false;
-
-	if (a->family == AF_INET)
-		addr_equals = a->addr.s_addr == b->addr.s_addr;
+	if (a->family == b->family) {
+		if (a->family == AF_INET)
+			addr_equals = a->addr.s_addr == b->addr.s_addr;
 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
-	else
-		addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
+		else
+			addr_equals = !ipv6_addr_cmp(&a->addr6, &b->addr6);
+	} else if (a->family == AF_INET) {
+		if (ipv6_addr_v4mapped(&b->addr6))
+			addr_equals = a->addr.s_addr == b->addr6.s6_addr32[3];
+	} else if (b->family == AF_INET) {
+		if (ipv6_addr_v4mapped(&a->addr6))
+			addr_equals = a->addr6.s6_addr32[3] == b->addr.s_addr;
 #endif
+	}
 
 	if (!addr_equals)
 		return false;
@@ -137,6 +142,7 @@  select_local_address(const struct pm_nl_pernet *pernet,
 		     struct mptcp_sock *msk)
 {
 	struct mptcp_pm_addr_entry *entry, *ret = NULL;
+	struct sock *sk = (struct sock *)msk;
 
 	rcu_read_lock();
 	__mptcp_flush_join_list(msk);
@@ -144,11 +150,20 @@  select_local_address(const struct pm_nl_pernet *pernet,
 		if (!(entry->addr.flags & MPTCP_PM_ADDR_FLAG_SUBFLOW))
 			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;
+		}
+
 		/* avoid any address already in use by subflows and
 		 * pending join
 		 */
-		if (entry->addr.family == ((struct sock *)msk)->sk_family &&
-		    !lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
+		if (!lookup_subflow_by_saddr(&msk->conn_list, &entry->addr)) {
 			ret = entry;
 			break;
 		}