public bool ChallengeResponse(CipheredChallenge response)
{
Console.WriteLine("Got ciphered challenge (" + response.Signature
+ ") response from " + response.Sender);
UserEntry pendingUser = null;
foreach (UserEntry e in waitingChallenge.Keys)
{
if (e.NodeId.Equals(response.Sender))
{
pendingUser = e;
break;
}
}
if (pendingUser == null)
return false;
RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
rsa.FromXmlString(pendingUser.PubKey); // load pending user's pubkey
try
{
if (rsa.VerifyData(waitingChallenge[pendingUser].Challenge, "SHA1", response.Signature))
{
Console.WriteLine("Received response matched challenge. " +
"(Verified with " + response.Sender + " public key)");
if (!IsRegistered(pendingUser.NodeId))
userDB.AddFirst(pendingUser);
else
// update timeout of user ( not implemented )
userDB.AddFirst(pendingUser);
waitingChallenge.Remove(pendingUser);
return true;
}
}
catch (CryptographicException ce)
{
Console.WriteLine("Could not confirm challenge for user: "******"\n"
+ ce.Message);
waitingChallenge.Remove(pendingUser);
return false;
}
return false;
}
public bool Register(UserEntry entryData)
{
RemoteAsyncUserRegisterDelegate registerDelegate =
new RemoteAsyncUserRegisterDelegate(pki.Register);
byte[] challenge = registerDelegate(entryData);
if (challenge == null)
return false; // wasn't allowed to register
// cipher challenge with private key
CipheredChallenge cc = new CipheredChallenge();
cc.Signature = rsa.SignData(challenge, "SHA1");
cc.Sender = entryData.NodeId;
// send to pki
RemoteAsyncUserRegisterChallengeResponseDelegate responseDelegate =
new RemoteAsyncUserRegisterChallengeResponseDelegate(pki.ChallengeResponse);
bool result = responseDelegate(cc);
return result;
}