Configure IP addresses without tun crate (i.e. do not use netsh)

| Variant          | Average (10 runs) | Speedup         |
|------------------|-------------------|-----------------|
| with netsh (main)| 3.824 s           | -               |
| without netsh    | 0.512 s           | ~7.5x faster    |

Variation within each variant was small (<= ~150 ms).

Test conditions:
- Relay: Sweden (any relay)
- Settings: No PQ, no obfuscation
- 10 iterations per variant, 10 s wait between attempts

1 files changed, 3 insertions, 14 deletions

diff --git a/talpid-tunnel/src/tun_provider/windows.rs b/talpid-tunnel/src/tun_provider/windows.rs
index 4be38b0877..e2b6ae3e1a 100644
--- a/talpid-tunnel/src/tun_provider/windows.rs
+++ b/talpid-tunnel/src/tun_provider/windows.rs
@@ -50,13 +50,6 @@ impl WindowsTunProvider {
 
     /// Open a tunnel using the current tunnel config.
     pub fn open_tun(&mut self) -> Result<WindowsTun, Error> {
-        let (first_addr, remaining_addrs) = self
-            .config
-            .addresses
-            .split_first()
-            .map(|(first, rest)| (Some(first), rest))
-            .unwrap_or((None, &[]));
-
         let mut tunnel_device = {
             let mut builder = TunnelDeviceBuilder::default();
 
@@ -65,12 +58,6 @@ impl WindowsTunProvider {
             // routes the highest possible priority.
             builder.config.metric(1);
 
-            // TODO: have tun either not use netsh or not set any default address at all
-            // TODO: tun can only set a single address
-            if let Some(addr) = first_addr {
-                builder.config.address(*addr);
-            }
-
             /// Tunnel adapter name
             const ADAPTER_NAME: &str = "Mullvad";
             /// Tunnel adapter GUID.
@@ -93,7 +80,9 @@ impl WindowsTunProvider {
             builder.create()?
         };
 
-        for ip in remaining_addrs {
+        // TODO: `tun` currently cannot handle IPv6 without using netsh,
+        // so we add IPs ourselves.
+        for ip in &self.config.addresses {
             tunnel_device.set_ip(*ip)?;
         }