net,dgram: add ipv6Only option for net and dgram

For TCP servers, the dual-stack support is enable by default, i.e.
binding host "::" will also make "0.0.0.0" bound. This commit add
ipv6Only option in `net.Server.listen()` and `dgram.createSocket()`
methods which allows to disable dual-stack support. Support for
cluster module is also provided in this commit.

Fixes: https://github.com/nodejs/node/issues/17664

PR-URL: https://github.com/nodejs/node/pull/23798
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: James M Snell <jasnell@gmail.com>

1 files changed, 51 insertions, 0 deletions

diff --git a/test/parallel/test-cluster-dgram-ipv6only.js b/test/parallel/test-cluster-dgram-ipv6only.js
new file mode 100644
index 0000000000..0906baec92
--- /dev/null
+++ b/test/parallel/test-cluster-dgram-ipv6only.js
@@ -0,0 +1,51 @@
+'use strict';
+
+const common = require('../common');
+if (!common.hasIPv6)
+  common.skip('no IPv6 support');
+if (common.isWindows)
+  common.skip('dgram clustering is currently not supported on windows.');
+
+const assert = require('assert');
+const cluster = require('cluster');
+const dgram = require('dgram');
+
+// This test ensures that the `ipv6Only` option in `dgram.createSock()`
+// works as expected.
+if (cluster.isMaster) {
+  cluster.fork().on('exit', common.mustCall((code) => {
+    assert.strictEqual(code, 0);
+  }));
+} else {
+  let waiting = 2;
+  function close() {
+    if (--waiting === 0)
+      cluster.worker.disconnect();
+  }
+
+  const socket1 = dgram.createSocket({
+    type: 'udp6',
+    ipv6Only: true
+  });
+  const socket2 = dgram.createSocket({
+    type: 'udp4',
+  });
+  socket1.on('error', common.mustNotCall());
+  socket2.on('error', common.mustNotCall());
+
+  socket1.bind({
+    port: 0,
+    address: '::',
+  }, common.mustCall(() => {
+    const { port } = socket1.address();
+    socket2.bind({
+      port,
+      address: '0.0.0.0',
+    }, common.mustCall(() => {
+      process.nextTick(() => {
+        socket1.close(close);
+        socket2.close(close);
+      });
+    }));
+  }));
+}