Is it recommended that I use an initialization vector to encrypt/decrypt my data? Will it make things more secure? Is it one of those things that need to be evaluated on a case by case basis?
To put this into actual context, the Win32 Cryptography function, CryptSetKeyParam allows for the setting of an initialization vector on a key prior to encrypting/decrypting. Other API's also allow for this.
What is generally recommended and why?
You need to use the same IV for encryption and decryption.
An initialization vector is used to avoid repetition during the data encryption process, making it impossible for hackers who use dictionary attack to decrypt the exchanged encrypted message by discovering a pattern.
AES algorithm requires two different parameters for encryption, a key and an initialization vector (IV).
Initialization vectors (IVs) are used to prevent a sequence of text that is identical to a previous sequence from producing the same exact ciphertext when encrypted. For example, packets have address fields that are generally fixed in location within the header of the packet.
An IV is essential when the same key might ever be used to encrypt more than one message.
The reason is because, under most encryption modes, two messages encrypted with the same key can be analyzed together. In a simple stream cipher, for instance, XORing two ciphertexts encrypted with the same key results in the XOR of the two messages, from which the plaintext can be easily extracted using traditional cryptanalysis techniques.
A weak IV is part of what made WEP breakable.
An IV basically mixes some unique, non-secret data into the key to prevent the same key ever being used twice.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With