[PATCH net-next v6 18/25] ovpn: add support for updating local UDP endpoint
From: Antonio Quartulli <antonio@openvpn.net>
Date: 2024-08-27 12:06:59
Subsystem:
networking drivers, openvpn data channel offload, the rest · Maintainers:
Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Antonio Quartulli, Linus Torvalds
In case of UDP links, the local endpoint used to communicate with a given peer may change without a connection restart. Add support for learning the new address in case of change. Signed-off-by: Antonio Quartulli <antonio@openvpn.net> --- drivers/net/ovpn/peer.c | 45 +++++++++++++++++++++++++++++++++++++++++ drivers/net/ovpn/peer.h | 3 +++ 2 files changed, 48 insertions(+)
diff --git a/drivers/net/ovpn/peer.c b/drivers/net/ovpn/peer.c
index a3f4f3231f3b..63e3e83b4fa5 100644
--- a/drivers/net/ovpn/peer.c
+++ b/drivers/net/ovpn/peer.c@@ -416,6 +416,51 @@ struct ovpn_peer *ovpn_peer_get_by_id(struct ovpn_struct *ovpn, u32 peer_id) return peer; } +/** + * ovpn_peer_update_local_endpoint - update local endpoint for peer + * @peer: peer to update the endpoint for + * @skb: incoming packet to retrieve the destination address (local) from + */ +void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, + struct sk_buff *skb) +{ + struct ovpn_bind *bind; + + rcu_read_lock(); + bind = rcu_dereference(peer->bind); + if (unlikely(!bind)) + goto unlock; + + spin_lock_bh(&peer->lock); + switch (skb_protocol_to_family(skb)) { + case AF_INET: + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { + netdev_dbg(peer->ovpn->dev, + "%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", + __func__, peer->id, &bind->local.ipv4.s_addr, + &ip_hdr(skb)->daddr); + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; + } + break; + case AF_INET6: + if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, + &ipv6_hdr(skb)->daddr))) { + netdev_dbg(peer->ovpn->dev, + "%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", + __func__, peer->id, &bind->local.ipv6, + &ipv6_hdr(skb)->daddr); + bind->local.ipv6 = ipv6_hdr(skb)->daddr; + } + break; + default: + break; + } + spin_unlock_bh(&peer->lock); + +unlock: + rcu_read_unlock(); +} + /** * ovpn_peer_get_by_dst - Lookup peer to send skb to * @ovpn: the private data representing the current VPN session
diff --git a/drivers/net/ovpn/peer.h b/drivers/net/ovpn/peer.h
index b632fabf9524..2b1b0ad3d309 100644
--- a/drivers/net/ovpn/peer.h
+++ b/drivers/net/ovpn/peer.h@@ -159,4 +159,7 @@ bool ovpn_peer_check_by_src(struct ovpn_struct *ovpn, struct sk_buff *skb, void ovpn_peer_keepalive_set(struct ovpn_peer *peer, u32 interval, u32 timeout); void ovpn_peer_keepalive_work(struct work_struct *work); +void ovpn_peer_update_local_endpoint(struct ovpn_peer *peer, + struct sk_buff *skb); + #endif /* _NET_OVPN_OVPNPEER_H_ */
--
2.44.2