Add ability to configure “own” addresses (#185)

* Add ability to configure “own” addresses

This configuration option permits the declaration of external or public
addresses instead of attempting to learn them from port forwarding or
interfaces. This is useful in situations where it isn’t possible to
accurately obtain the correct external addresses that peers should use.

* Update args and use better parse listen address

Add the --advertise_addresses control argument to accompany the new
configuration option. Also parse the listen address/port to extract the
port to advertise with advertise_addresses instead of assuming it is
just a port.

src/cloud.rs

@@ -29,7 +29,7 @@ use crate::{
         AddrList, NodeInfo, PeerInfo, MESSAGE_TYPE_CLOSE, MESSAGE_TYPE_DATA, MESSAGE_TYPE_KEEPALIVE,
         MESSAGE_TYPE_NODE_INFO,
     },
-    net::{mapped_addr, Socket},
+    net::{mapped_addr, parse_listen, Socket},
     payload::Protocol,
     poll::{WaitImpl, WaitResult},
     port_forwarding::PortForwarding,
@@ -222,11 +222,26 @@ impl<D: Device, P: Protocol, S: Socket, TS: TimeSource> GenericCloud<D, P, S, TS
 
     pub fn reset_own_addresses(&mut self) -> io::Result<()> {
         self.own_addresses.clear();
+        if self.config.advertise_addresses.len() > 0 &&
+            !self.config.listen.starts_with("ws://") {
+                // Force advertised addresses based on configuration instead
+                // of discovery. Note: Disables port forwarding
+                // Because the listen config may contain a color (aka
+                // both address and port are specified) we parse it and
+                // then extract just the port.
+                let sockaddr = parse_listen(&self.config.listen);
+                let port = sockaddr.port();
+                for address in &self.config.advertise_addresses {
+                    let sockaddr = try_fail!(SocketAddr::from_str(&format!("{}:{}", address, port)), "Invalid IP Address or port {}");
+                    self.own_addresses.push(sockaddr);
+                }
+            } else {
                 self.own_addresses.push(self.socket.address().map(mapped_addr)?);
                 if let Some(ref pfw) = self.port_forwarding {
                     self.own_addresses.push(pfw.get_internal_ip().into());
                     self.own_addresses.push(pfw.get_external_ip().into());
                 }
+            }
         debug!("Own addresses: {:?}", self.own_addresses);
         // TODO: detect address changes and call event
         Ok(())

src/config.rs

@@ -19,6 +19,7 @@ pub struct Config {
     pub fix_rp_filter: bool,
 
     pub ip: Option<String>,
+    pub advertise_addresses: Vec<String>,
     pub ifup: Option<String>,
     pub ifdown: Option<String>,
 
@@ -56,6 +57,7 @@ impl Default for Config {
             device_path: None,
             fix_rp_filter: false,
             ip: None,
+            advertise_addresses: vec![],
             ifup: None,
             ifdown: None,
             crypto: CryptoConfig::default(),
@@ -105,6 +107,9 @@ impl Config {
         if let Some(val) = file.ip {
             self.ip = Some(val);
         }
+        if let Some(mut val) = file.advertise_addresses {
+            self.advertise_addresses.append(&mut val);
+        }
         if let Some(val) = file.ifup {
             self.ifup = Some(val);
         }
@@ -212,6 +217,7 @@ impl Config {
         if let Some(val) = args.ifup {
             self.ifup = Some(val);
         }
+        self.advertise_addresses.append(&mut args.advertise_addresses);
         if let Some(val) = args.ifdown {
             self.ifdown = Some(val);
         }
@@ -318,6 +324,7 @@ impl Config {
             ifup: self.ifup,
             ifdown: self.ifdown,
             ip: self.ip,
+            advertise_addresses: Some(self.advertise_addresses),
             keepalive: self.keepalive,
             listen: Some(self.listen),
             mode: Some(self.mode),
@@ -467,6 +474,10 @@ pub struct Args {
     #[structopt(long)]
     pub ip: Option<String>,
 
+    /// A list of IP Addresses to advertise as our external address(s)
+    #[structopt(long = "advertise_addresses", use_delimiter = true)]
+    pub advertise_addresses: Vec<String>,
+
     /// A command to setup the network interface
     #[structopt(long)]
     pub ifup: Option<String>,
@@ -606,6 +617,7 @@ pub struct ConfigFile {
     pub device: Option<ConfigFileDevice>,
 
     pub ip: Option<String>,
+    pub advertise_addresses: Option<Vec<String>>,
     pub ifup: Option<String>,
     pub ifdown: Option<String>,
 
@@ -638,6 +650,9 @@ device:
   name: vpncloud%d
   path: /dev/net/tun
 ip: 10.0.1.1/16
+advertise-addresses:
+  - 192.168.0.1
+  - 192.168.1.1
 ifup: ifconfig $IFNAME 10.0.1.1/16 mtu 1400 up
 ifdown: 'true'
 peers:
@@ -673,6 +688,7 @@ statsd:
                 fix_rp_filter: None
             }),
             ip: Some("10.0.1.1/16".to_string()),
+            advertise_addresses: Some(vec!["192.168.0.1".to_string(), "192.168.1.1".to_string()]),
             ifup: Some("ifconfig $IFNAME 10.0.1.1/16 mtu 1400 up".to_string()),
             ifdown: Some("true".to_string()),
             crypto: CryptoConfig::default(),
@@ -721,6 +737,7 @@ fn config_merge() {
             fix_rp_filter: None,
         }),
         ip: None,
+        advertise_addresses: Some(vec![]),
         ifup: Some("ifconfig $IFNAME 10.0.1.1/16 mtu 1400 up".to_string()),
         ifdown: Some("true".to_string()),
         crypto: CryptoConfig::default(),
@@ -757,6 +774,7 @@ fn config_merge() {
             device_name: "vpncloud%d".to_string(),
             device_path: None,
             ip: None,
+            advertise_addresses: vec![],
             ifup: Some("ifconfig $IFNAME 10.0.1.1/16 mtu 1400 up".to_string()),
             ifdown: Some("true".to_string()),
             listen: "3210".to_string(),
@@ -816,6 +834,8 @@ fn config_merge() {
             device_path: Some("/dev/null".to_string()),
             fix_rp_filter: false,
             ip: None,
+            advertise_addresses: vec![],
+
             ifup: Some("ifconfig $IFNAME 10.0.1.2/16 mtu 1400 up".to_string()),
             ifdown: Some("ifconfig $IFNAME down".to_string()),
             crypto: CryptoConfig { password: Some("anothersecret".to_string()), ..CryptoConfig::default() },

src/oldconfig.rs

@@ -109,6 +109,7 @@ impl OldConfigFile {
             ifdown: self.ifdown,
             ifup: self.ifup,
             ip: None,
+            advertise_addresses: None,
             keepalive: self.keepalive,
             listen: self.listen.or(self.port.map(|p| format!("{}", p))),
             mode: self.mode,