I'm currently working on crypto tools to encrypt/decrypt 4 blocks of messages using Triple-DES with 2 keys. So, I've reached the final cipher text, but now I have to do the reverse and get the plaintext message. However I'm sort of confused with the decryption process.
For the Encryption, I encrypted using K1, decrypted used K2 and encrypted again using K1, then I XOR-ed the result with the 2nd block of plaintext message and so on, until I reached the last one. Now I want to decrypt and I'm sort of confused on where the XOR-ing comes in.