internal-grain128.h File Reference

Internal implementation of the Grain-128 stream cipher. More...

#include "internal-util.h"

Go to the source code of this file.

Data Structures
struct	grain128_state_t
	Representation of the state of Grain-128. More...

Functions
void	grain128_core (grain128_state_t *state, uint32_t x, uint32_t x2)
	Performs 32 rounds of Grain-128 in parallel. More...
uint32_t	grain128_preoutput (const grain128_state_t *state)
	Generates 32 bits of pre-output data. More...
void	grain128_setup (grain128_state_t *state, const unsigned char *key, const unsigned char *nonce)
	Sets up the initial Grain-128 state with the key and nonce. More...
void	grain128_authenticate (grain128_state_t *state, const unsigned char *data, size_t len)
	Authenticates data with Grain-128. More...
void	grain128_encrypt (grain128_state_t *state, unsigned char *c, const unsigned char *m, size_t len)
	Encrypts and authenticates data with Grain-128. More...
void	grain128_decrypt (grain128_state_t *state, unsigned char *m, const unsigned char *c, size_t len)
	Decrypts and authenticates data with Grain-128. More...
void	grain128_compute_tag (grain128_state_t *state)
	Computes the final authentiation tag. More...

Detailed Description

Internal implementation of the Grain-128 stream cipher.

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

Function Documentation

void grain128_authenticate	(	grain128_state_t *	state,
		const unsigned char *	data,
		size_t	len
	)

Authenticates data with Grain-128.

Parameters

state	Grain-128 state.
data	Points to the data to be authenticated.
len	Length of the data to be authenticated.

void grain128_compute_tag

(

grain128_state_t *

state

)

Computes the final authentiation tag.

Parameters

state

Grain-128 state.

The final authentication tag is written to the first 8 bytes of state->ks.

void grain128_core	(	grain128_state_t *	state,
		uint32_t	x,
		uint32_t	x2
	)

Performs 32 rounds of Grain-128 in parallel.

Parameters

state	Grain-128 state.
x	32 bits of input to be incorporated into the LFSR state, or zero.
x2	Another 32 bits to be incorporated into the NFSR state, or zero.

void grain128_decrypt	(	grain128_state_t *	state,
		unsigned char *	m,
		const unsigned char *	c,
		size_t	len
	)

Decrypts and authenticates data with Grain-128.

Parameters

state	Grain-128 state.
m	Points to the plaintext output buffer.
c	Points to the ciphertext input buffer.
len	Length of the data to be decrypted.

void grain128_encrypt	(	grain128_state_t *	state,
		unsigned char *	c,
		const unsigned char *	m,
		size_t	len
	)

Encrypts and authenticates data with Grain-128.

Parameters

state	Grain-128 state.
c	Points to the ciphertext output buffer.
m	Points to the plaintext input buffer.
len	Length of the data to be encrypted.

uint32_t grain128_preoutput

(

const grain128_state_t *

state

)

Generates 32 bits of pre-output data.

Parameters

state

Grain-128 state.

Returns

The generated 32 bits of pre-output data.

void grain128_setup	(	grain128_state_t *	state,
		const unsigned char *	key,
		const unsigned char *	nonce
	)

Sets up the initial Grain-128 state with the key and nonce.

Parameters

state	Grain-128 state to be initialized.
key	Points to the 128-bit key.
nonce	Points to the 96-bit nonce.