Crypto.Saltine.Core.AEAD

Secret-key authenticated encryption with additional data (AEAD): Crypto.Saltine.Core.AEAD

The aead function encrypts and authenticates a message ByteString and additional authenticated data ByteString using a secret key and a nonce. The aeadOpen function verifies and decrypts a ciphertext ByteString using a secret key and a nonce. If the ciphertext fails validation, aeadOpen returns Nothing.

The Crypto.Saltine.Core.AEAD module is designed to meet the standard notions of privacy and authenticity for a secret-key authenticated-encryption scheme using nonces. For formal definitions see, e.g., Bellare and Namprempre, "Authenticated encryption: relations among notions and analysis of the generic composition paradigm," Lecture Notes in Computer Science 1976 (2000), 531–545, http://www-cse.ucsd.edu/~mihir/papers/oem.html.

Note that the length is not hidden. Note also that it is the caller's responsibility to ensure the uniqueness of nonces—for example, by using nonce 1 for the first message, nonce 2 for the second message, etc. Nonces are long enough that randomly generated nonces have negligible risk of collision.

Documentation

data Key

An opaque secretbox cryptographic key.

Instances

Eq Key

Defined in Crypto.Saltine.Core.AEAD

Methods

(==) :: Key -> Key -> Bool

(/=) :: Key -> Key -> Bool

Ord Key

Defined in Crypto.Saltine.Core.AEAD

Methods

compare :: Key -> Key -> Ordering

(<) :: Key -> Key -> Bool

(<=) :: Key -> Key -> Bool

(>) :: Key -> Key -> Bool

(>=) :: Key -> Key -> Bool

max :: Key -> Key -> Key

min :: Key -> Key -> Key

IsEncoding Key

Defined in Crypto.Saltine.Core.AEAD

Methods

encode :: Key -> ByteString

decode :: ByteString -> Maybe Key

encoded :: (Choice p, Applicative f) => p Key (f Key) -> p ByteString (f ByteString)

data Nonce

An opaque secretbox nonce.

Instances

Eq Nonce

Defined in Crypto.Saltine.Core.AEAD

Methods

(==) :: Nonce -> Nonce -> Bool

(/=) :: Nonce -> Nonce -> Bool

Ord Nonce

Defined in Crypto.Saltine.Core.AEAD

Methods

compare :: Nonce -> Nonce -> Ordering

(<) :: Nonce -> Nonce -> Bool

(<=) :: Nonce -> Nonce -> Bool

(>) :: Nonce -> Nonce -> Bool

(>=) :: Nonce -> Nonce -> Bool

max :: Nonce -> Nonce -> Nonce

min :: Nonce -> Nonce -> Nonce

IsNonce Nonce

Defined in Crypto.Saltine.Core.AEAD

Methods

zero :: Nonce

nudge :: Nonce -> Nonce

IsEncoding Nonce

Defined in Crypto.Saltine.Core.AEAD

Methods

encode :: Nonce -> ByteString

decode :: ByteString -> Maybe Nonce

encoded :: (Choice p, Applicative f) => p Nonce (f Nonce) -> p ByteString (f ByteString)

aead

Arguments

:: Key

-> Nonce

-> ByteString

Message

-> ByteString

AAD

-> ByteString

Ciphertext

Encrypts a message. It is infeasible for an attacker to decrypt the message so long as the Nonce is never repeated.

aeadOpen

Arguments

:: Key

-> Nonce

-> ByteString

Ciphertext

-> ByteString

AAD

-> Maybe ByteString

Message

Decrypts a message. Returns Nothing if the keys and message do not match.

aeadDetached

Arguments

:: Key

-> Nonce

-> ByteString

Message

-> ByteString

AAD

-> (ByteString, ByteString)

Tag, Ciphertext

Encrypts a message. It is infeasible for an attacker to decrypt the message so long as the Nonce is never repeated.

aeadOpenDetached

Arguments

:: Key

-> Nonce

-> ByteString

Tag

-> ByteString

Ciphertext

-> ByteString

AAD

-> Maybe ByteString

Message

Decrypts a message. Returns Nothing if the keys and message do not match.

newKey :: IO Key

Creates a random key of the correct size for secretbox.

newNonce :: IO Nonce

Creates a random nonce of the correct size for secretbox.