Thread: DH Key Exchange and Blowfish

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/ I have completely re-written this post to make my question clearer
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I am trying to write a test server for a client (I am only interested in the server mechanisms not client). I wasn't able to see the codes for the client, but i know client

- performs a DH exchange with server by first accepting server p, g, server public key
- after formulating it's client shared key, client returns server it's own public key for server to establish shared key.
- immediately client sends server a verification packet that is encrypted with blowfish using shared key as the blowfish key
- server has to decode this verification msg

I have set up my server to accommodate the above description, and having prior knowledge of what the decryption outcome(verification) would be, the result is not quite what i wanted. These are my codes used for DH exchange and blowfish, which part of it might have resulted in the unexpected decryption.

 
        //getting ready key objects
        KeyPairGenerator kpairGen = KeyPairGenerator.getInstance("DiffieHellman");
        DHParameterSpec dhparam = new DHParameterSpec(new BigInteger(P, 16), new BigInteger(G, 16));
        kpairGen.initialize(dhparam);
        KeyPair kpair = kpairGen.generateKeyPair();
        String ServerPrivateKey = ((DHPrivateKey) kpair.getPrivate()).getX().toString(16);
        String ServerPublicKey = ((DHPublicKey) kpair.getPublic()).getY().toString(16);
 
        //Send server p, g, public key to client
        ClientHandler.write( packetBuilder(P,G,ServerPublicKey) );
 
        //obtain client public key
        int byteRead = ClientHandler.read(packetBuffer);
        String ClientPublicKey = new String( trimPacket(packetBuffer,byteRead) );
 
        //Generate ServerClient SharedKey
        KeyAgreement agreement = KeyAgreement.getInstance("DiffieHellman");
        agreement.init(ServerPrivateKey);
        agreement.doPhase(ClientPublicKey, true);
        SecretKey sharedKey = agreement.generateSecret("Blowfish");
 
        //obtain client verification
        int byteRead = ClientHandler.read(packetBuffer);
        byte[] verification = trimPacket(packetBuffer,byteRead);
 
        //Decrypt the msg
        Cipher blowfish = Cipher.getInstance("Blowfish/CFB/NoPadding");
        blowfish.init(Cipher.DECRYPT_MODE, sharedKey, DecryptIV);
        byte[] result = blowfish.doFinal(p);
 
        //This result does not make any sense.

Also, after obtaining the result, i have initialized the cipher to encrypt mode and encrypted the decoded msg. The before decryption verification packet is same as the post encryption verification packet; there isn't anything wrong with the way blowfish is carried out. So what's wrong with my key?