Configure custom DNS servers in tun provider

2 files changed, 29 insertions, 1 deletions

diff --git a/talpid-core/src/tunnel/tun_provider/android/mod.rs b/talpid-core/src/tunnel/tun_provider/android/mod.rs
index 7aa54d8d03..4c136ef189 100644
--- a/talpid-core/src/tunnel/tun_provider/android/mod.rs
+++ b/talpid-core/src/tunnel/tun_provider/android/mod.rs
@@ -60,11 +60,16 @@ pub struct AndroidTunProvider {
     object: GlobalRef,
     last_tun_config: TunConfig,
     allow_lan: bool,
+    custom_dns_servers: Option<Vec<IpAddr>>,
 }
 
 impl AndroidTunProvider {
     /// Create a new AndroidTunProvider interfacing with Android's VpnService.
-    pub fn new(context: AndroidContext, allow_lan: bool) -> Self {
+    pub fn new(
+        context: AndroidContext,
+        allow_lan: bool,
+        custom_dns_servers: Option<Vec<IpAddr>>,
+    ) -> Self {
         let env = JnixEnv::from(
             context
                 .jvm
@@ -79,6 +84,7 @@ impl AndroidTunProvider {
             object: context.vpn_service,
             last_tun_config: TunConfig::default(),
             allow_lan,
+            custom_dns_servers,
         }
     }
 
@@ -91,6 +97,15 @@ impl AndroidTunProvider {
         Ok(())
     }
 
+    pub fn set_custom_dns_servers(&mut self, servers: Option<Vec<IpAddr>>) -> Result<(), Error> {
+        if self.custom_dns_servers != servers {
+            self.custom_dns_servers = servers;
+            self.recreate_tun_if_open()?;
+        }
+
+        Ok(())
+    }
+
     /// Retrieve a tunnel device with the provided configuration.
     pub fn get_tun(&mut self, config: TunConfig) -> Result<VpnServiceTun, Error> {
         let tun_fd = self.get_tun_fd(config.clone())?;
@@ -213,6 +228,11 @@ impl AndroidTunProvider {
     }
 
     fn prepare_tun_config(&self, config: &mut TunConfig) {
+        self.prepare_tun_config_for_allow_lan(config);
+        self.prepare_tun_config_for_custom_dns(config);
+    }
+
+    fn prepare_tun_config_for_allow_lan(&self, config: &mut TunConfig) {
         if self.allow_lan {
             let (required_ipv4_routes, required_ipv6_routes) = config
                 .required_routes
@@ -253,6 +273,12 @@ impl AndroidTunProvider {
         }
     }
 
+    fn prepare_tun_config_for_custom_dns(&self, config: &mut TunConfig) {
+        if let Some(custom_dns_servers) = self.custom_dns_servers.clone() {
+            config.dns_servers = custom_dns_servers;
+        }
+    }
+
     fn call_method(
         &self,
         name: &'static str,
diff --git a/talpid-core/src/tunnel_state_machine/mod.rs b/talpid-core/src/tunnel_state_machine/mod.rs
index 79f3ca7021..cfe7ec3306 100644
--- a/talpid-core/src/tunnel_state_machine/mod.rs
+++ b/talpid-core/src/tunnel_state_machine/mod.rs
@@ -100,6 +100,8 @@ pub async fn spawn(
         android_context,
         #[cfg(target_os = "android")]
         allow_lan,
+        #[cfg(target_os = "android")]
+        custom_dns.clone(),
     );
 
     let runtime = tokio::runtime::Handle::current();