Peer: prefer v4 endpoints to v6

This works around DNS64 XLAT changeovers. Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2018-10-01 17:13:14 +02:00
parent 49a9475c4a
commit c23d58bc27
2 changed files with 79 additions and 33 deletions
@@ -0,0 +1,71 @@
+/*
+ * Copyright © 2017-2018 WireGuard LLC. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package com.wireguard.config;
+
+import android.annotation.SuppressLint;
+
+import com.wireguard.android.Application;
+import com.wireguard.android.R;
+
+import java.net.Inet4Address;
+import java.net.InetAddress;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.net.UnknownHostException;
+
+import javax.annotation.Nullable;
+
+public class InetEndpoint {
+    private final String host;
+    private final int port;
+    @Nullable private InetAddress resolvedHost;
+
+    public InetEndpoint(@Nullable final String endpoint) {
+        if (endpoint.indexOf('/') != -1 || endpoint.indexOf('?') != -1 || endpoint.indexOf('#') != -1)
+            throw new IllegalArgumentException(Application.get().getString(R.string.tunnel_error_forbidden_endpoint_chars));
+        final URI uri;
+        try {
+            uri = new URI("wg://" + endpoint);
+        } catch (final URISyntaxException e) {
+            throw new IllegalArgumentException(e);
+        }
+        host = uri.getHost();
+        port = uri.getPort();
+    }
+
+    public String getHost() {
+        return host;
+    }
+
+    public int getPort() {
+        return port;
+    }
+
+    @SuppressLint("DefaultLocale")
+    public String getResolvedEndpoint() throws UnknownHostException {
+        if (resolvedHost == null) {
+            final InetAddress[] candidates = InetAddress.getAllByName(host);
+            if (candidates.length == 0)
+                throw new UnknownHostException(host);
+            for (final InetAddress addr : candidates) {
+                if (addr instanceof Inet4Address) {
+                    resolvedHost = addr;
+                    break;
+                }
+            }
+            if (resolvedHost == null)
+                resolvedHost = candidates[0];
+        }
+        return String.format(resolvedHost instanceof Inet4Address ?
+                "[%s]:%d" : "%s:%d", resolvedHost.getHostAddress(), port);
+    }
+
+    @SuppressLint("DefaultLocale")
+    public String getEndpoint() {
+        return String.format(host.contains(":") && !host.contains("[") ?
+                "[%s]:%d" : "%s:%d", host, port);
+    }
+}