Remodel the Model

- The configuration and crypto model is now entirely independent
of Android classes other than Nullable and TextUtils.
- Model classes are immutable and use builders that enforce the
appropriate optional/required attributes.
- The Android config proxies (for Parcelable and databinding) are
moved to the Android side of the codebase, and are designed to be
safe for two-way databinding. This allows proper observability in
TunnelDetailFragment.
- Various robustness fixes and documentation updates to helper classes.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 20 insertions, 9 deletions

diff --git a/app/src/main/java/com/wireguard/config/InetAddresses.java b/app/src/main/java/com/wireguard/config/InetAddresses.java
index c50c5a0e..989598da 100644
--- a/app/src/main/java/com/wireguard/config/InetAddresses.java
+++ b/app/src/main/java/com/wireguard/config/InetAddresses.java
@@ -5,21 +5,22 @@
 
 package com.wireguard.config;
 
-import android.support.annotation.Nullable;
-
-import com.wireguard.android.Application;
-import com.wireguard.android.R;
-
 import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
+import java.net.Inet4Address;
+import java.net.Inet6Address;
 import java.net.InetAddress;
 
+/**
+ * Utility methods for creating instances of {@link InetAddress}.
+ */
 public final class InetAddresses {
     private static final Method PARSER_METHOD;
 
     static {
         try {
             // This method is only present on Android.
+            // noinspection JavaReflectionMemberAccess
             PARSER_METHOD = InetAddress.class.getMethod("parseNumericAddress", String.class);
         } catch (final NoSuchMethodException e) {
             throw new RuntimeException(e);
@@ -30,13 +31,23 @@ public final class InetAddresses {
         // Prevent instantiation.
     }
 
-    public static InetAddress parse(@Nullable final String address) {
-        if (address == null || address.isEmpty())
-            throw new IllegalArgumentException(Application.get().getString(R.string.tunnel_error_empty_inetaddress));
+    /**
+     * Parses a numeric IPv4 or IPv6 address without performing any DNS lookups.
+     *
+     * @param address a string representing the IP address
+     * @return an instance of {@link Inet4Address} or {@link Inet6Address}, as appropriate
+     */
+    public static InetAddress parse(final String address) {
+        if (address.isEmpty())
+            throw new IllegalArgumentException("Empty address");
         try {
             return (InetAddress) PARSER_METHOD.invoke(null, address);
         } catch (final IllegalAccessException | InvocationTargetException e) {
-            throw new RuntimeException(e.getCause() == null ? e : e.getCause());
+            final Throwable cause = e.getCause();
+            // Re-throw parsing exceptions with the original type, as callers might try to catch
+            // them. On the other hand, callers cannot be expected to handle reflection failures.
+            throw cause instanceof IllegalArgumentException ?
+                    (IllegalArgumentException) cause : new RuntimeException(e);
         }
     }
 }