Reducing published peer timeout to 5 min on NAT

CHANGELOG.md

@@ -4,6 +4,8 @@ This project follows [semantic versioning](http://semver.org).
 
 ### Unreleased
 
+- [added] Exchange peer timeout and adapt keepalive accordingly
+- [added] Reducing published peer timeout to 5 min when NAT is detected
 - [changed] Rust version 1.41.0
 - [changed] Updated dependencies
 

src/cloud.rs

@@ -227,6 +227,7 @@ pub struct GenericCloud<D: Device, P: Protocol, T: Table, S: Socket, TS: TimeSou
     device: D,
     crypto: Crypto,
     next_peerlist: Time,
+    peer_timeout_publish: u16,
     update_freq: u16,
     buffer_out: [u8; 64 * 1024],
     next_housekeep: Time,
@@ -255,15 +256,22 @@ impl<D: Device, P: Protocol, T: Table, S: Socket, TS: TimeSource> GenericCloud<D
             Err(err) => fail!("Failed to open ipv6 address ::{}: {}", config.port, err)
         };
         let now = TS::now();
+        let peer_timeout_publish = if S::detect_nat() {
+            info!("Private IP detected, setting published peer timeout to 300s");
+            300
+        } else {
+            config.peer_timeout as u16
+        };
         let mut res = GenericCloud {
             magic: config.get_magic(),
             node_id: random(),
-            peers: PeerList::new(config.peer_timeout as Duration),
+            peers: PeerList::new(config.peer_timeout),
             addresses,
             learning,
             broadcast,
             reconnect_peers: Vec::new(),
             own_addresses: Vec::new(),
+            peer_timeout_publish,
             table,
             socket4,
             socket6,
@@ -414,7 +422,7 @@ impl<D: Device, P: Protocol, T: Table, S: Socket, TS: TimeSource> GenericCloud<D
         // Send a message to each resolved address
         for a in resolve(&addr)? {
             // Ignore error this time
-            let mut msg = Message::Init(0, node_id, subnets.clone(), self.config.peer_timeout as u16);
+            let mut msg = Message::Init(0, node_id, subnets.clone(), self.peer_timeout_publish);
             self.send_msg(a, &mut msg).ok();
         }
         Ok(())
@@ -435,7 +443,7 @@ impl<D: Device, P: Protocol, T: Table, S: Socket, TS: TimeSource> GenericCloud<D
         debug!("Connecting to {:?}", addr);
         let subnets = self.addresses.clone();
         let node_id = self.node_id;
-        let mut msg = Message::Init(0, node_id, subnets.clone(), self.config.peer_timeout as u16);
+        let mut msg = Message::Init(0, node_id, subnets.clone(), self.peer_timeout_publish);
         self.send_msg(addr, &mut msg)
     }
 
@@ -725,7 +733,7 @@ impl<D: Device, P: Protocol, T: Table, S: Socket, TS: TimeSource> GenericCloud<D
                     let own_node_id = self.node_id;
                     self.send_msg(
                         peer,
-                        &mut Message::Init(stage + 1, own_node_id, own_addrs, self.config.peer_timeout as u16)
+                        &mut Message::Init(stage + 1, own_node_id, own_addrs, self.peer_timeout_publish)
                     )?;
                 }
                 // Send peers in any case

src/net.rs

@@ -5,6 +5,8 @@ use std::{
     os::unix::io::{AsRawFd, RawFd}
 };
 
+use super::util::get_internal_ip;
+
 use net2::UdpBuilder;
 
 
@@ -14,6 +16,7 @@ pub trait Socket: AsRawFd + Sized {
     fn receive(&mut self, buffer: &mut [u8]) -> Result<(usize, SocketAddr), io::Error>;
     fn send(&mut self, data: &[u8], addr: SocketAddr) -> Result<usize, io::Error>;
     fn address(&self) -> Result<SocketAddr, io::Error>;
+    fn detect_nat() -> bool;
 }
 
 impl Socket for UdpSocket {
@@ -42,6 +45,9 @@ impl Socket for UdpSocket {
     fn address(&self) -> Result<SocketAddr, io::Error> {
         self.local_addr()
     }
+    fn detect_nat() -> bool {
+        get_internal_ip().is_private()
+    }
 }
 
 
@@ -95,4 +101,7 @@ impl Socket for MockSocket {
     fn address(&self) -> Result<SocketAddr, io::Error> {
         Ok(self.address)
     }
+    fn detect_nat() -> bool {
+        false
+    }
 }

src/port_forwarding.rs

@@ -2,16 +2,13 @@
 // Copyright (C) 2015-2019  Dennis Schwerdel
 // This software is licensed under GPL-3 or newer (see LICENSE.md)
 
-use std::{
-    io,
-    net::{SocketAddr, SocketAddrV4, UdpSocket}
-};
+use std::{io, net::SocketAddrV4};
 
 use igd::*;
 
-use super::util::{SystemTimeSource, Time, TimeSource};
+use super::util::{get_internal_ip, SystemTimeSource, Time, TimeSource};
 
-const LEASE_TIME: u32 = 300;
+const LEASE_TIME: u32 = 1800;
 const DESCRIPTION: &str = "VpnCloud";
 
 
@@ -40,16 +37,7 @@ impl PortForwarding {
             }
         };
         info!("Port-forwarding: found router at {}", gateway.addr);
-        // Get the internal address (this trick gets the address by opening a UDP connection which
-        // does not really open anything but returns the correct address)
-        let dummy_sock = UdpSocket::bind("0.0.0.0:0").expect("Failed to bind");
-        dummy_sock.connect(gateway.addr).expect("Failed to connect");
-        let internal_addr;
-        if let SocketAddr::V4(addr) = dummy_sock.local_addr().expect("Failed to get local address") {
-            internal_addr = SocketAddrV4::new(*addr.ip(), port);
-        } else {
-            unreachable!()
-        }
+        let internal_addr = SocketAddrV4::new(get_internal_ip(), port);
         // Query the external address
         let external_ip = match gateway.get_external_ip() {
             Ok(ip) => ip,

src/util.rs

@@ -4,7 +4,7 @@
 
 use std::{
     fmt,
-    net::{SocketAddr, ToSocketAddrs},
+    net::{Ipv4Addr, SocketAddr, ToSocketAddrs, UdpSocket},
     sync::atomic::{AtomicIsize, Ordering}
 };
 
@@ -115,6 +115,18 @@ macro_rules! try_fail {
     } );
 }
 
+pub fn get_internal_ip() -> Ipv4Addr {
+    // Get the internal address (this trick gets the address by opening a UDP connection which
+    // does not really open anything but returns the correct address)
+    let dummy_sock = UdpSocket::bind("0.0.0.0:0").expect("Failed to bind");
+    dummy_sock.connect("8.8.8.8:53").expect("Failed to connect");
+    if let SocketAddr::V4(addr) = dummy_sock.local_addr().expect("Failed to get local address") {
+        *addr.ip()
+    } else {
+        unreachable!()
+    }
+}
+
 
 #[allow(unknown_lints, clippy::needless_pass_by_value)]
 pub fn resolve<Addr: ToSocketAddrs + fmt::Debug>(addr: Addr) -> Result<Vec<SocketAddr>, Error> {