private void NegotiateAuthentication(string streamPassword, bool client)
{
int oldReadTimeout = baseStream.ReadTimeout;
baseStream.ReadTimeout = 5000;
RSACryptoServiceProvider localKeys;
RSACryptoServiceProvider remoteKey;
// Generate and send public key
{
localKeys = new RSACryptoServiceProvider();
byte[] publicBlob = localKeys.ExportCspBlob(false);
baseStream.Write(BitConverter.GetBytes(publicBlob.Length), 0, 4);
baseStream.Write(publicBlob, 0, publicBlob.Length);
}
// Receive remote public key
try
{
byte[] blobLen = new byte[4];
StreamHelper.ForceReadAll(baseStream, blobLen, 0, 4);
byte[] remoteBlob = new byte[BitConverter.ToInt32(blobLen, 0)];
StreamHelper.ForceReadAll(baseStream, remoteBlob, 0, remoteBlob.Length);
remoteKey = new RSACryptoServiceProvider();
remoteKey.ImportCspBlob(remoteBlob);
} catch (Exception) {
throw new EncryptedNetworkStreamException(EncryptedNetworkStreamException.Reason.NetworkError);
}
rsaStream = new RSAStream(baseStream, localKeys, remoteKey);
AesCryptoServiceProvider aesKey = new AesCryptoServiceProvider();
aesKey.KeySize = 256;
// Authenticate client/server
byte[] passwordHash = MD5.Create().ComputeHash(ASCIIEncoding.UTF8.GetBytes(streamPassword));
if (client)
{
// If we're the client, send the password hash (encrypted)
rsaStream.Write(passwordHash, 0, 16);
// Read AES key
byte[] lenBuffer = new byte[4];
StreamHelper.ForceReadAll(rsaStream, lenBuffer, 0, 4);
byte[] aesKeyBuffer = new Byte[BitConverter.ToInt32(lenBuffer, 0)];
StreamHelper.ForceReadAll(rsaStream, aesKeyBuffer, 0, aesKeyBuffer.Length);
StreamHelper.ForceReadAll(rsaStream, lenBuffer, 0, 4);
byte[] aesIVBuffer = new Byte[BitConverter.ToInt32(lenBuffer, 0)];
StreamHelper.ForceReadAll(rsaStream, aesIVBuffer, 0, aesIVBuffer.Length);
aesKey.Key = aesKeyBuffer;
aesKey.IV = aesIVBuffer;
} else {
// If we're the server, wait for them to send the password (encrypted)
byte[] receivedPasswordHash = new byte[16];
StreamHelper.ForceReadAll(rsaStream, receivedPasswordHash, 0, 16);
if (! passwordHash.SequenceEqual(receivedPasswordHash))
throw new EncryptedNetworkStreamException(EncryptedNetworkStreamException.Reason.InvalidAuthentication);
// Generate/send AES key
aesKey.GenerateKey();
aesKey.GenerateIV();
// Group length and key togeather to lower overhead
byte[] keyDataBuffer = SerializedArray.ToNetworkBytes(aesKey.Key);
rsaStream.Write(keyDataBuffer, 0, keyDataBuffer.Length);
byte[] keyIVBuffer = SerializedArray.ToNetworkBytes(aesKey.IV);
rsaStream.Write(keyIVBuffer, 0, keyIVBuffer.Length);
}
aesStream = new AESStream(baseStream, aesKey);
baseStream.ReadTimeout = oldReadTimeout;
}
private void NegotiateAuthentication(string streamPassword, bool client)
{
int oldReadTimeout = baseStream.ReadTimeout;
baseStream.ReadTimeout = 5000;
RSACryptoServiceProvider localKeys;
RSACryptoServiceProvider remoteKey;
// Generate and send public key
{
localKeys = new RSACryptoServiceProvider();
byte[] publicBlob = localKeys.ExportCspBlob(false);
baseStream.Write(BitConverter.GetBytes(publicBlob.Length), 0, 4);
baseStream.Write(publicBlob, 0, publicBlob.Length);
}
// Receive remote public key
try
{
byte[] blobLen = new byte[4];
StreamHelper.ForceReadAll(baseStream, blobLen, 0, 4);
byte[] remoteBlob = new byte[BitConverter.ToInt32(blobLen, 0)];
StreamHelper.ForceReadAll(baseStream, remoteBlob, 0, remoteBlob.Length);
remoteKey = new RSACryptoServiceProvider();
remoteKey.ImportCspBlob(remoteBlob);
} catch (Exception) {
throw new EncryptedNetworkStreamException(EncryptedNetworkStreamException.Reason.NetworkError);
}
rsaStream = new RSAStream(baseStream, localKeys, remoteKey);
AesCryptoServiceProvider aesKey = new AesCryptoServiceProvider();
aesKey.KeySize = 256;
// Authenticate client/server
byte[] passwordHash = MD5.Create().ComputeHash(ASCIIEncoding.UTF8.GetBytes(streamPassword));
if (client)
{
// If we're the client, send the password hash (encrypted)
rsaStream.Write(passwordHash, 0, 16);
// Read AES key
byte[] lenBuffer = new byte[4];
StreamHelper.ForceReadAll(rsaStream, lenBuffer, 0, 4);
byte[] aesKeyBuffer = new Byte[BitConverter.ToInt32(lenBuffer, 0)];
StreamHelper.ForceReadAll(rsaStream, aesKeyBuffer, 0, aesKeyBuffer.Length);
StreamHelper.ForceReadAll(rsaStream, lenBuffer, 0, 4);
byte[] aesIVBuffer = new Byte[BitConverter.ToInt32(lenBuffer, 0)];
StreamHelper.ForceReadAll(rsaStream, aesIVBuffer, 0, aesIVBuffer.Length);
aesKey.Key = aesKeyBuffer;
aesKey.IV = aesIVBuffer;
}
else
{
// If we're the server, wait for them to send the password (encrypted)
byte[] receivedPasswordHash = new byte[16];
StreamHelper.ForceReadAll(rsaStream, receivedPasswordHash, 0, 16);
if (!passwordHash.SequenceEqual(receivedPasswordHash))
{
throw new EncryptedNetworkStreamException(EncryptedNetworkStreamException.Reason.InvalidAuthentication);
}
// Generate/send AES key
aesKey.GenerateKey();
aesKey.GenerateIV();
// Group length and key togeather to lower overhead
byte[] keyDataBuffer = SerializedArray.ToNetworkBytes(aesKey.Key);
rsaStream.Write(keyDataBuffer, 0, keyDataBuffer.Length);
byte[] keyIVBuffer = SerializedArray.ToNetworkBytes(aesKey.IV);
rsaStream.Write(keyIVBuffer, 0, keyIVBuffer.Length);
}
aesStream = new AESStream(baseStream, aesKey);
baseStream.ReadTimeout = oldReadTimeout;
}
