Copyright	(c) 2013 Stefan Bühler
License	MIT-style (see the file COPYING)
Maintainer	stbuehler@web.de
Stability	experimental
Portability	portable
Safe Haskell	None
Language	Haskell98

Crypto.Nettle.ChaChaPoly1305

Contents

ChaCha-Poly1305

Description

This module exports the ChaCha-Poly1305 AEAD cipher supported by nettle: http://www.lysator.liu.se/~nisse/nettle/

Both ChaCha (the underlying cipher) and Poly1305 (the keyed hash) were designed by D. J. Bernstein.

Synopsis

ChaCha-Poly1305

chaChaPoly1305Encrypt Source #

Arguments

:: B.ByteString	`key` (must be 32 bytes)
-> B.ByteString	`nonce` (must be 12 bytes)
-> B.ByteString	`aad` additional data to be verified
-> B.ByteString	`plain` data to encrypt
-> (B.ByteString, B.ByteString)	returns (`cipher`, `tag`) ciphertext and verification tag

Encrypt plain text and create a verification tag for the encrypted text and some additional data. key and nonce must not be reused together. The returned tag is 16 bytes long, but may be shortened for verification (losing security).

chaChaPoly1305Decrypt :: B.ByteString -> B.ByteString -> B.ByteString -> B.ByteString -> B.ByteString -> Maybe B.ByteString Source #

Decrypt cipher text and verify a (possible shortened) tag for the encrypted text and some additional data. key and nonce must not be reused together.