Stream ciphers are completely broken and will be removed soon. New users must use AEAD ciphers.
This historic document is for educational purposes only.
Stream_encrypt is a function that takes a secret key, an initialization vector, a message, and produces a ciphertext with the same length as the message.
Stream_encrypt(key, IV, message) => ciphertext
Stream_decrypt is a function that takes a secret key, an initializaiton vector, a ciphertext, and produces the original message.
Stream_decrypt(key, IV, ciphertext) => message
The key can be input directly from user or generated from a password. The key derivation is following
EVP_BytesToKey(3) in OpenSSL. The detailed spec can be found here: https://wiki.openssl.org/index.php/Manual:EVP_BytesToKey(3)
A stream cipher encrypted TCP stream starts with a randomly generated initializaiton vector, followed by encrypted payload data.
A stream cipher encrypted UDP packet has the following structure
Each UDP packet is encrypted/decrypted independently with a randomly generated initialization vector.
Historic stream ciphers
|Name||Key Size||IV Length|