cannote receive the symmetric key...:(
hey everyone,
i am using a pub/priv key pair to exchange messages from a client to a server using certificates. There comes a time when i want to send a symmetric key from the server to the client and switch to symmetric encryption. This packet should contain the symmetric key signed and encrypted..
In my server i create a symmetric key as follows:
SecretKey symmetricKey=null;
try{
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(new SecureRandom());
symmetricKey = kg.generateKey();
}catch(Exception e){
System.out.println("Exception "+e);//fix it
}
in the message that should contain the symmetric key i do the following
pcktSymmetricKey.setSignature(sign((new String(symmetricKey.getEncoded())), myPrivateKey));
pcktSymmetricKey.setMsgEncrypted(encryptAsymmetric(symmetricKey.getEncoded(),clientPublicKey));
DatagramPacket sentPacket2 = serializeObject(pcktSymmetricKey);
socket.send(sentPacket2);
in the client side i declare a SecretKey using the following (and this may be the problem
SecretKey symmetricKey=null;
and then when i receive the packet i do the following :
pcktSymmetricKey=(MyPacketMessageEncrypted)deserializeObject(receivedUdpPacket);
byte[] decryptedMsg2=decryptAsymmetric(pcktSymmetricKey.getMsgEncrypted(), myPrivateKey);
boolean statusSignature2=checkSignature(pcktSymmetricKey, decryptedMsg2, serverPublicKey);
System.out.println("status of the signature of the symmetric key :"+statusSignature2);//this prints TRUE!
and the problem is here.. i cannot find a way to import the symmetric key that is now decrypted in the decryptedMsg2 in bytes and set it to the symmetricKey variable... i am trying to find a way to use the SecretKeyFactory but i cannot make it work.. how should i initialise the SecretKey or the SecretKeyFactory and how should i convert the bytes that hold the symmetric key to store it to a variable and use it later with symmetric cryptography..?
many thanks!!
