PrivateKeyFile: Add validateKeyPairs()

Router: Validate router key pairs read in from file

core/java/src/net/i2p/data/PrivateKeyFile.java

@@ -53,7 +53,7 @@ public class PrivateKeyFile {
     
     protected final File file;
     private final I2PClient client;
-    private Destination dest;
+    protected Destination dest;
     protected PrivateKey privKey;
     protected SigningPrivateKey signingPrivKey; 
 
@@ -455,6 +455,23 @@ public class PrivateKeyFile {
         }
     }
 
+    /**
+     *  Verify that the PublicKey matches the PrivateKey, and
+     *  the SigningPublicKey matches the SigningPrivateKey.
+     *
+     *  @return success
+     *  @since 0.9.16
+     */
+    public boolean validateKeyPairs() {
+        try {
+            if (!dest.getPublicKey().equals(KeyGenerator.getPublicKey(privKey)))
+                return false;
+            return dest.getSigningPublicKey().equals(KeyGenerator.getSigningPublicKey(signingPrivKey));
+        } catch (IllegalArgumentException iae) {
+            return false;
+        }
+    }
+
     @Override
     public String toString() {
         StringBuilder s = new StringBuilder(128);