Don't strip scopeId when resolving ipv6 address (#12019)

Motivation:

Due a bug we did strip the scopeId of the ipv6 address string when using the DnsNameResolver. This could later then result to things like "No Route to host" exceptions.

Modifications:

- Add new method to NetUtil which will create the InetAddress for an string that contains an ip while still preserve the scopeId.
- Use this new method
- Add unit tests.

Result:

Fixes #11563

common/src/main/java/io/netty/util/NetUtil.java

@@ -277,6 +277,59 @@ public static byte[] createByteArrayFromIpAddressString(String ipAddressString)
         return null;
     }
 
+    /**
+     * Creates an {@link InetAddress} based on an ipAddressString or might return null if it can't be parsed.
+     * No error handling is performed here.
+     */
+    public static InetAddress createInetAddressFromIpAddressString(String ipAddressString) {
+        if (isValidIpV4Address(ipAddressString)) {
+            byte[] bytes = validIpV4ToBytes(ipAddressString);
+            try {
+                return InetAddress.getByAddress(bytes);
+            } catch (UnknownHostException e) {
+                // Should never happen!
+                throw new IllegalStateException(e);
+            }
+        }
+
+        if (isValidIpV6Address(ipAddressString)) {
+            if (ipAddressString.charAt(0) == '[') {
+                ipAddressString = ipAddressString.substring(1, ipAddressString.length() - 1);
+            }
+
+            int percentPos = ipAddressString.indexOf('%');
+            if (percentPos >= 0) {
+                try {
+                    int scopeId = Integer.parseInt(ipAddressString.substring(percentPos + 1));
+                    ipAddressString = ipAddressString.substring(0, percentPos);
+                    byte[] bytes = getIPv6ByName(ipAddressString, true);
+                    if (bytes == null) {
+                        return null;
+                    }
+                    try {
+                        return Inet6Address.getByAddress(null, bytes, scopeId);
+                    } catch (UnknownHostException e) {
+                        // Should never happen!
+                        throw new IllegalStateException(e);
+                    }
+                } catch (NumberFormatException e) {
+                    return null;
+                }
+            }
+            byte[] bytes = getIPv6ByName(ipAddressString, true);
+            if (bytes == null) {
+                return null;
+            }
+            try {
+                return InetAddress.getByAddress(bytes);
+            } catch (UnknownHostException e) {
+                // Should never happen!
+                throw new IllegalStateException(e);
+            }
+        }
+        return null;
+    }
+
     private static int decimalDigit(String str, int pos) {
         return str.charAt(pos) - '0';
     }

resolver-dns/src/main/java/io/netty/resolver/dns/DnsNameResolver.java

@@ -902,10 +902,10 @@ protected void doResolve(String inetHost,
             promise.setSuccess(loopbackAddress());
             return;
         }
-        final byte[] bytes = NetUtil.createByteArrayFromIpAddressString(inetHost);
-        if (bytes != null) {
+        final InetAddress address = NetUtil.createInetAddressFromIpAddressString(inetHost);
+        if (address != null) {
             // The inetHost is actually an ipaddress.
-            promise.setSuccess(InetAddress.getByAddress(bytes));
+            promise.setSuccess(address);
             return;
         }
 
@@ -1004,10 +1004,10 @@ protected void doResolveAll(String inetHost,
             promise.setSuccess(Collections.singletonList(loopbackAddress()));
             return;
         }
-        final byte[] bytes = NetUtil.createByteArrayFromIpAddressString(inetHost);
-        if (bytes != null) {
+        final InetAddress address = NetUtil.createInetAddressFromIpAddressString(inetHost);
+        if (address != null) {
             // The unresolvedAddress was created via a String that contains an ipaddress.
-            promise.setSuccess(Collections.singletonList(InetAddress.getByAddress(bytes)));
+            promise.setSuccess(Collections.singletonList(address));
             return;
         }
 

resolver-dns/src/test/java/io/netty/resolver/dns/DnsNameResolverTest.java

@@ -76,6 +76,7 @@
 import java.io.InputStream;
 import java.net.DatagramSocket;
 import java.net.Inet4Address;
+import java.net.Inet6Address;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.net.ServerSocket;
@@ -3470,4 +3471,96 @@ private static void assertNotEmptyAndRelease(Future<List<DnsRecord>> recordsFutu
             ReferenceCountUtil.release(record);
         }
     }
+
+    @Test
+    public void testResolveIpv6WithScopeId() throws Exception {
+        testResolveIpv6WithScopeId0(false);
+    }
+
+    @Test
+    public void testResolveAllIpv6WithScopeId() throws Exception {
+        testResolveIpv6WithScopeId0(true);
+    }
+
+    private void testResolveIpv6WithScopeId0(boolean resolveAll) throws Exception {
+        DnsNameResolver resolver = newResolver().build();
+        String address = "fe80:0:0:0:1c31:d1d1:4824:72a9";
+        int scopeId = 15;
+        String addressString = address + '%' + scopeId;
+        byte[] bytes =  NetUtil.createByteArrayFromIpAddressString(address);
+        Inet6Address inet6Address = Inet6Address.getByAddress(null, bytes, scopeId);
+        try {
+            final InetAddress addr;
+            if (resolveAll) {
+                List<InetAddress> addressList = resolver.resolveAll(addressString).getNow();
+                assertEquals(1, addressList.size());
+                addr = addressList.get(0);
+            } else {
+                addr = resolver.resolve(addressString).getNow();
+            }
+            assertEquals(inet6Address, addr);
+        } finally {
+            resolver.close();
+        }
+    }
+
+    @Test
+    public void testResolveIpv6WithoutScopeId() throws Exception {
+        testResolveIpv6WithoutScopeId0(false);
+    }
+
+    @Test
+    public void testResolveAllIpv6WithoutScopeId() throws Exception {
+        testResolveIpv6WithoutScopeId0(true);
+    }
+
+    private void testResolveIpv6WithoutScopeId0(boolean resolveAll) throws Exception {
+        DnsNameResolver resolver = newResolver().build();
+        String addressString = "fe80:0:0:0:1c31:d1d1:4824:72a9";
+        byte[] bytes =  NetUtil.createByteArrayFromIpAddressString(addressString);
+        Inet6Address inet6Address = (Inet6Address) InetAddress.getByAddress(bytes);
+        try {
+            final InetAddress addr;
+            if (resolveAll) {
+                List<InetAddress> addressList = resolver.resolveAll(addressString).getNow();
+                assertEquals(1, addressList.size());
+                addr = addressList.get(0);
+            } else {
+                addr = resolver.resolve(addressString).getNow();
+            }
+            assertEquals(inet6Address, addr);
+        } finally {
+            resolver.close();
+        }
+    }
+
+    @Test
+    public void testResolveIp4() throws Exception {
+        testResolveIp4(false);
+    }
+
+    @Test
+    public void testResolveAllIp4() throws Exception {
+        testResolveIp4(true);
+    }
+
+    private void testResolveIp4(boolean resolveAll) throws Exception {
+        DnsNameResolver resolver = newResolver().build();
+        String addressString = "10.0.0.1";
+        byte[] bytes =  NetUtil.createByteArrayFromIpAddressString(addressString);
+        InetAddress inetAddress = InetAddress.getByAddress(bytes);
+        try {
+            final InetAddress addr;
+            if (resolveAll) {
+                List<InetAddress> addressList = resolver.resolveAll(addressString).getNow();
+                assertEquals(1, addressList.size());
+                addr = addressList.get(0);
+            } else {
+                addr = resolver.resolve(addressString).getNow();
+            }
+            assertEquals(inetAddress, addr);
+        } finally {
+            resolver.close();
+        }
+    }
 }