v6 hole punch (#873)

Some devices have ipv6 but don't allow input connection, this patch add hole punching for these devices.

- **add v6 hole punch msg to udp tunnel**
- **send hole punch packet when do ipv6 direct connect**

easytier/src/peers/peer_manager.rs

@@ -389,6 +389,15 @@ impl PeerManager {
         });
     }
 
+    pub async fn add_direct_tunnel(
+        &self,
+        t: Box<dyn Tunnel>,
+    ) -> Result<(PeerId, PeerConnId), Error> {
+        let (peer_id, conn_id) = self.add_client_tunnel(t).await?;
+        self.add_directly_connected_conn(peer_id, conn_id);
+        Ok((peer_id, conn_id))
+    }
+
     #[tracing::instrument]
     pub async fn try_direct_connect<C>(
         &self,
@@ -401,9 +410,7 @@ impl PeerManager {
         let t = ns
             .run_async(|| async move { connector.connect().await })
             .await?;
-        let (peer_id, conn_id) = self.add_client_tunnel(t).await?;
-        self.add_directly_connected_conn(peer_id, conn_id);
-        Ok((peer_id, conn_id))
+        self.add_direct_tunnel(t).await
     }
 
     #[tracing::instrument]

easytier/src/peers/peer_rpc_service.rs

@@ -1,9 +1,15 @@
+use std::net::SocketAddr;
+
 use crate::{
     common::global_ctx::ArcGlobalCtx,
     proto::{
-        peer_rpc::{DirectConnectorRpc, GetIpListRequest, GetIpListResponse},
+        common::Void,
+        peer_rpc::{
+            DirectConnectorRpc, GetIpListRequest, GetIpListResponse, SendV6HolePunchPacketRequest,
+        },
         rpc_types::{self, controller::BaseController},
     },
+    tunnel::udp,
 };
 
 #[derive(Clone)]
@@ -30,8 +36,42 @@ impl DirectConnectorRpc for DirectConnectorManagerRpcServer {
             .chain(self.global_ctx.get_running_listeners().into_iter())
             .map(Into::into)
             .collect();
+        tracing::trace!(
+            "get_ip_list: public_ipv4: {:?}, public_ipv6: {:?}, listeners: {:?}",
+            ret.public_ipv4,
+            ret.public_ipv6,
+            ret.listeners
+        );
         Ok(ret)
     }
+
+    async fn send_v6_hole_punch_packet(
+        &self,
+        _: BaseController,
+        req: SendV6HolePunchPacketRequest,
+    ) -> rpc_types::error::Result<Void> {
+        let listener_port = req.listener_port as u16;
+        let SocketAddr::V6(connector_addr) = req
+            .connector_addr
+            .ok_or(anyhow::anyhow!("connector_addr is required"))?
+            .into()
+        else {
+            return Err(anyhow::anyhow!("connector_addr is not a v6 address").into());
+        };
+
+        tracing::info!(
+            "Sending v6 hole punch packet to {} from listener port {}",
+            connector_addr,
+            listener_port
+        );
+
+        // send 3 packets to the connector
+        for _ in 0..3 {
+            udp::send_v6_hole_punch_packet(listener_port, connector_addr).await?;
+            tokio::time::sleep(std::time::Duration::from_millis(30)).await;
+        }
+        Ok(Default::default())
+    }
 }
 
 impl DirectConnectorManagerRpcServer {