# OFB

OFB mode works by using an initialization vector (IV) and a secret key to generate a keystream. The keystream is then XORed with the plaintext to produce the ciphertext. The IV is a random value that is used to initialize the encryption process. It is important that the IV is unique and unpredictable to ensure the security of the encryption.

The encryption process in OFB mode is iterative. The encryption function takes the IV and the secret key as inputs and generates a block of keystream. This keystream block is then XORed with the plaintext block to produce the ciphertext block. The same process is repeated for each subsequent plaintext block, using the previous keystream block as the input for the encryption function.

<figure><img src="https://github.com/Hakumarachi/theCTFRecipe/blob/master/.gitbook/assets/Schema_ofb.png" alt=""><figcaption></figcaption></figure>


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