SAM: Fix checkPrivateDestination() for key certs (ticket #1318)

apps/sam/java/src/net/i2p/sam/SAMUtils.java

@@ -79,15 +79,26 @@ class SAMUtils {
     }
     
     public static class InvalidDestinationException extends Exception {
-    	static final long serialVersionUID = 0x1 ;
+    	private static final long serialVersionUID = 0x1;
     }
+
+
+    /**
+     * Check whether a base64-encoded {dest,privkey,signingprivkey} is valid
+     *
+     * @param dest The base64-encoded destination and keys to be checked (same format as PrivateKeyFile)
+     *
+     * @throws InvalidDestination if invalid
+     */
     public static void checkPrivateDestination(String dest) throws InvalidDestinationException {
     	ByteArrayInputStream destKeyStream = new ByteArrayInputStream(Base64.decode(dest));
 
     	try {
-    		new Destination().readBytes(destKeyStream);
+    		Destination d = new Destination();
+    		d.readBytes(destKeyStream);
     		new PrivateKey().readBytes(destKeyStream);
-    		new SigningPrivateKey().readBytes(destKeyStream);
+    		SigningPrivateKey spk = new SigningPrivateKey(d.getSigningPublicKey().getType());
+    		spk.readBytes(destKeyStream);
     	} catch (Exception e) {
     		throw new InvalidDestinationException();
     	}