grain-aead.h File Reference

Grain-128AEAD authenticated encryption algorithm. More...

#include <stddef.h>

Go to the source code of this file.

Macros
#define	GRAIN128_KEY_SIZE   16
	Size of the key for Grain-128AEAD.
#define	GRAIN128_TAG_SIZE   8
	Size of the authentication tag for Grain-128AEAD.
#define	GRAIN128_NONCE_SIZE   12
	Size of the nonce for Grain-128AEAD.

Functions
int	grain128_aead_encrypt (unsigned char *c, size_t *clen, const unsigned char *m, size_t mlen, const unsigned char *ad, size_t adlen, const unsigned char *npub, const unsigned char *k)
	Encrypts and authenticates a packet with Grain-128AEAD. More...
int	grain128_aead_decrypt (unsigned char *m, size_t *mlen, const unsigned char *c, size_t clen, const unsigned char *ad, size_t adlen, const unsigned char *npub, const unsigned char *k)
	Decrypts and authenticates a packet with Grain-128AEAD. More...

Detailed Description

Grain-128AEAD authenticated encryption algorithm.

Grain-128AEAD is an authenticated encryption algorithm based around a combination of a 128-bit linear feedback shift register (LFSR) and a 128-bit non-linear feedback shift register (NFSR). It is a member of the Grain family of stream ciphers.

References: https://grain-128aead.github.io/

Function Documentation

int grain128_aead_decrypt	(	unsigned char *	m,
		size_t *	mlen,
		const unsigned char *	c,
		size_t	clen,
		const unsigned char *	ad,
		size_t	adlen,
		const unsigned char *	npub,
		const unsigned char *	k
	)

Decrypts and authenticates a packet with Grain-128AEAD.

Parameters

m	Buffer to receive the plaintext message on output.
mlen	Receives the length of the plaintext message on output.
c	Buffer that contains the ciphertext and authentication tag to decrypt.
clen	Length of the input data in bytes, which includes the ciphertext and the 8 byte authentication tag.
ad	Buffer that contains associated data to authenticate along with the packet but which does not need to be encrypted.
adlen	Length of the associated data in bytes.
npub	Points to the public nonce for the packet which must be 12 bytes in length.
k	Points to the 16 bytes of the key to use to decrypt the packet.

Returns

0 on success, -1 if the authentication tag was incorrect, or some other negative number if there was an error in the parameters.

See Also

grain128_aead_encrypt()

int grain128_aead_encrypt	(	unsigned char *	c,
		size_t *	clen,
		const unsigned char *	m,
		size_t	mlen,
		const unsigned char *	ad,
		size_t	adlen,
		const unsigned char *	npub,
		const unsigned char *	k
	)

Encrypts and authenticates a packet with Grain-128AEAD.

Parameters

c	Buffer to receive the output.
clen	On exit, set to the length of the output which includes the ciphertext and the 8 byte authentication tag.
m	Buffer that contains the plaintext message to encrypt.
mlen	Length of the plaintext message in bytes.
ad	Buffer that contains associated data to authenticate along with the packet but which does not need to be encrypted.
adlen	Length of the associated data in bytes.
npub	Points to the public nonce for the packet which must be 12 bytes in length.
k	Points to the 16 bytes of the key to use to encrypt the packet.

Returns

0 on success, or a negative value if there was an error in the parameters.

See Also

grain128_aead_decrypt()