IPv6 enabled

src/lib.rs

@@ -99,6 +99,7 @@ pub struct Options {
     virtual_dns: Option<virtdns::VirtualDns>,
     mtu: Option<usize>,
     dns_over_tcp: bool,
+    ipv6_enabled: bool,
 }
 
 impl Options {
@@ -118,6 +119,11 @@ impl Options {
         self
     }
 
+    pub fn with_ipv6(mut self) -> Self {
+        self.ipv6_enabled = true;
+        self
+    }
+
     pub fn with_mtu(mut self, mtu: usize) -> Self {
         self.mtu = Some(mtu);
         self

src/main.rs

@@ -29,6 +29,14 @@ struct Args {
     #[arg(short, long, value_name = "method", value_enum, default_value = "virtual")]
     dns: ArgDns,
 
+    /// Enable DNS over TCP
+    #[arg(long)]
+    dns_over_tcp: bool,
+
+    /// IPv6 enabled
+    #[arg(short = '6', long)]
+    ipv6_enabled: bool,
+
     /// Routing and system setup
     #[arg(short, long, value_name = "method", value_enum)]
     setup: Option<ArgSetup>,
@@ -40,10 +48,6 @@ struct Args {
     /// Verbosity level
     #[arg(short, long, value_name = "level", value_enum, default_value = "info")]
     verbosity: ArgVerbosity,
-
-    /// Enable DNS over TCP
-    #[arg(long)]
-    dns_over_tcp: bool,
 }
 
 #[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, clap::ValueEnum)]
@@ -87,6 +91,10 @@ fn main() -> ExitCode {
         options = options.with_dns_over_tcp();
     }
 
+    if args.ipv6_enabled {
+        options = options.with_ipv6();
+    }
+
     let interface = match args.tun_fd {
         None => NetworkInterface::Named(args.tun.clone()),
         Some(fd) => {

src/tun2proxy.rs

@@ -184,7 +184,6 @@ struct ConnectionState {
     udp_origin_dst: Option<SocketAddr>,
     udp_data_cache: LinkedList<Vec<u8>>,
     udp_over_tcp_expiry: Option<::std::time::Instant>,
-    is_tcp_dns: bool,
 }
 
 pub(crate) trait TcpProxy {
@@ -494,7 +493,6 @@ impl<'a> TunToProxy<'a> {
             let tcp_proxy_handler = manager.new_tcp_proxy(info, false)?;
             let server_addr = manager.get_server_addr();
             let mut state = self.create_new_tcp_connection_state(server_addr, origin_dst, tcp_proxy_handler, false)?;
-            state.is_tcp_dns = true;
             state.udp_origin_dst = Some(SocketAddr::try_from(original_info.dst.clone())?);
             self.connection_map.insert(info.clone(), state);
 
@@ -578,7 +576,9 @@ impl<'a> TunToProxy<'a> {
                 .tcp_proxy_handler
                 .consume_data(OutgoingDirection::ToClient, len + 2);
 
-            dns::remove_ipv6_entries(&mut message); // TODO: Configurable
+            if !self.options.ipv6_enabled {
+                dns::remove_ipv6_entries(&mut message);
+            }
 
             to_send.push_back(message.to_vec()?);
             if len + 2 == buf.len() {
@@ -778,7 +778,6 @@ impl<'a> TunToProxy<'a> {
             udp_origin_dst: None,
             udp_data_cache: LinkedList::new(),
             udp_over_tcp_expiry: None,
-            is_tcp_dns: false,
         };
         Ok(state)
     }
@@ -929,7 +928,9 @@ impl<'a> TunToProxy<'a> {
 
                 let buf = if info.dst.port() == DNS_PORT {
                     let mut message = dns::parse_data_to_dns_message(&buf[header.len()..], false)?;
-                    dns::remove_ipv6_entries(&mut message); // TODO: Configurable
+                    if !self.options.ipv6_enabled {
+                        dns::remove_ipv6_entries(&mut message);
+                    }
                     message.to_vec()?
                 } else {
                     buf[header.len()..].to_vec()