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 d78726718ec40126c93624310ce627ddbd210816..3055804894a1331243833379631c1d2e6a138238 100644 --- a/drivers/net/ovpn/peer.c +++ b/drivers/net/ovpn/peer.c @@ -508,6 +508,51 @@ static void ovpn_peer_remove(struct ovpn_peer *peer, schedule_work(&peer->remove_work); }
+/** + * 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) { + case htons(ETH_P_IP): + if (unlikely(bind->local.ipv4.s_addr != ip_hdr(skb)->daddr)) { + net_dbg_ratelimited("%s: learning local IPv4 for peer %d (%pI4 -> %pI4)\n", + netdev_name(peer->ovpn->dev), + peer->id, &bind->local.ipv4.s_addr, + &ip_hdr(skb)->daddr); + bind->local.ipv4.s_addr = ip_hdr(skb)->daddr; + } + break; + case htons(ETH_P_IPV6): + if (unlikely(!ipv6_addr_equal(&bind->local.ipv6, + &ipv6_hdr(skb)->daddr))) { + net_dbg_ratelimited("%s: learning local IPv6 for peer %d (%pI6c -> %pI6c\n", + netdev_name(peer->ovpn->dev), + 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 c69774877c84f0f335fc7ab8fc5da0c555c0794c..ebe7ef12ff9b63d4eabefcfed1e89454aa2f96a4 100644 --- a/drivers/net/ovpn/peer.h +++ b/drivers/net/ovpn/peer.h @@ -154,4 +154,7 @@ bool ovpn_peer_check_by_src(struct ovpn_priv *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_ */