From e9bee485ae74ed17468abad6a91f2fa8ff1dc61d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marcel=20M=C3=A4rtens?= <marcel.cochem@googlemail.com>
Date: Sat, 29 Jan 2022 18:18:30 +0100
Subject: [PATCH] Add a test for the new gameserver IPv6 IPv4 behavior

---
 network/tests/helper.rs      |  8 ++++----
 network/tests/integration.rs | 37 ++++++++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/network/tests/helper.rs b/network/tests/helper.rs
index b22df211b4..517e8ea3a9 100644
--- a/network/tests/helper.rs
+++ b/network/tests/helper.rs
@@ -1,6 +1,6 @@
 use lazy_static::*;
 use std::{
-    net::SocketAddr,
+    net::{Ipv4Addr, SocketAddr},
     sync::{
         atomic::{AtomicU16, AtomicU64, Ordering},
         Arc,
@@ -89,8 +89,8 @@ pub fn tcp() -> (ListenAddr, ConnectAddr) {
     }
     let port = PORTS.fetch_add(1, Ordering::Relaxed);
     (
-        ListenAddr::Tcp(SocketAddr::from(([127, 0, 0, 1], port))),
-        ConnectAddr::Tcp(SocketAddr::from(([127, 0, 0, 1], port))),
+        ListenAddr::Tcp(SocketAddr::from((Ipv4Addr::LOCALHOST, port))),
+        ConnectAddr::Tcp(SocketAddr::from((Ipv4Addr::LOCALHOST, port))),
     )
 }
 
@@ -117,7 +117,7 @@ pub fn quic() -> (ListenAddr, ConnectAddr) {
     let server_config = quinn::ServerConfig::with_single_cert(vec![cert], key)
         .expect("Server Config Cert/Key failed");
     let client_config = quinn::ClientConfig::with_root_certificates(root_store);
-    use std::net::{IpAddr, Ipv4Addr};
+    use std::net::IpAddr;
     (
         ListenAddr::Quic(
             SocketAddr::new(IpAddr::V4(Ipv4Addr::LOCALHOST), port),
diff --git a/network/tests/integration.rs b/network/tests/integration.rs
index d49c7a49ef..0ee4e76b7f 100644
--- a/network/tests/integration.rs
+++ b/network/tests/integration.rs
@@ -262,3 +262,40 @@ fn multiple_try_recv() {
     assert_eq!(s1_b.try_recv::<String>(), Err(StreamError::StreamClosed));
     drop((_n_a, _n_b, _p_a, _p_b)); //clean teardown
 }
+
+/// If we listen on a IPv6 UNSPECIFIED address, on linux it will automatically
+/// listen on the respective IPv4 address. This must not be as we should behave
+/// similar under windows and linux.
+#[test]
+fn listen_on_ipv6_doesnt_block_ipv4() {
+    let (_, _) = helper::setup(false, 0);
+    let tcpv4 = tcp();
+    let port = if let ListenAddr::Tcp(x) = tcpv4.0 {
+        x.port()
+    } else {
+        unreachable!()
+    };
+    let tcpv6 = (
+        ListenAddr::Tcp(std::net::SocketAddr::from((
+            std::net::Ipv6Addr::UNSPECIFIED,
+            port,
+        ))),
+        ConnectAddr::Tcp(std::net::SocketAddr::from((
+            std::net::Ipv6Addr::UNSPECIFIED,
+            port,
+        ))),
+    );
+
+    let (_r, _n_a, _p_a, mut s1_a, _n_b, _p_b, mut s1_b) = network_participant_stream(tcpv6);
+    std::thread::sleep(SLEEP_EXTERNAL);
+    let (_r2, _n_a2, _p_a2, mut s1_a2, _n_b2, _p_b2, mut s1_b2) = network_participant_stream(tcpv4);
+
+    s1_a.send(42u32).unwrap();
+    s1_a2.send(1337u32).unwrap();
+    std::thread::sleep(SLEEP_EXTERNAL);
+    assert_eq!(s1_b.try_recv::<u32>(), Ok(Some(42u32)));
+    assert_eq!(s1_b2.try_recv::<u32>(), Ok(Some(1337u32)));
+
+    drop((s1_a, s1_b, _n_a, _n_b, _p_a, _p_b));
+    drop((s1_a2, s1_b2, _n_a2, _n_b2, _p_a2, _p_b2)); //clean teardown
+}