H = sha1.digest();
Signature signature = Factory.Named.Util.create(trans.getConfig().getSignatureFactories(),
KeyType.fromKey(hostKey).toString());
signature.init(hostKey, null);
signature.update(H, 0, H.length);
if (!signature.verify(sig))
throw new TransportException(DisconnectReason.KEY_EXCHANGE_FAILED,
"KeyExchange signature verification failed");
return true;
}