Masked version of the Gimli authenticated encryption algorithm. More...

#include "aead-common.h"

Data Structures
union	gimli24_hash_state_t
	State information for GIMLI-24-HASH incremental modes. More...

Macros
#define	GIMLI24_KEY_SIZE 32
	Size of the key for GIMLI-24.

#define	GIMLI24_NONCE_SIZE 16
	Size of the nonce for GIMLI-24.

#define	GIMLI24_TAG_SIZE 16
	Size of the authentication tag for GIMLI-24.

#define	GIMLI24_HASH_SIZE 32
	Size of the hash output for GIMLI-24.

Functions
int	gimli24_aead_encrypt (unsigned char c, unsigned long long clen, const unsigned char m, unsigned long long mlen, const unsigned char ad, unsigned long long adlen, const unsigned char nsec, const unsigned char npub, const unsigned char *k)
	Encrypts and authenticates a packet with GIMLI-24 using the full AEAD mode. More...

int	gimli24_aead_decrypt (unsigned char m, unsigned long long mlen, unsigned char nsec, const unsigned char c, unsigned long long clen, const unsigned char ad, unsigned long long adlen, const unsigned char npub, const unsigned char *k)
	Decrypts and authenticates a packet with GIMLI-24 using the full AEAD mode. More...

int	gimli24_hash (unsigned char out, const unsigned char in, unsigned long long inlen)
	Hashes a block of input data with GIMLI-24 to generate a hash value. More...

void	gimli24_hash_init (gimli24_hash_state_t *state)
	Initializes the state for a GIMLI-24-HASH hashing operation. More...

void	gimli24_hash_absorb (gimli24_hash_state_t state, const unsigned char in, unsigned long long inlen)
	Aborbs more input data into a GIMLI-24-HASH state. More...

void	gimli24_hash_squeeze (gimli24_hash_state_t state, unsigned char out, unsigned long long outlen)
	Squeezes output data from an GIMLI-24-HASH state. More...

void	gimli24_hash_finalize (gimli24_hash_state_t state, unsigned char out)
	Returns the final hash value from a GIMLI-24-HASH hashing operation. More...

Variables
aead_cipher_t const	gimli24_cipher
	Meta-information block for the GIMLI-24 cipher.

aead_hash_algorithm_t const	gimli24_hash_algorithm
	Meta-information block for the GIMLI-24-HASH algorithm. More...

Detailed Description

Masked version of the Gimli authenticated encryption algorithm.

Gimli authenticated encryption algorithm.

This algorithm is experimental and is not one of the NIST competition submissions. It uses a masked version of the GIMLI24 permutation to absorb the key and nonce in the first block, and then switches to the regular GIMLI24 permutation for the associated data and plaintext.

The theory (as yet unproven) is that this construction will provide some protection for the key against power analysis side channels. Please let me know what I've done wrong if this theory is incorrect.

References: https://gimli.cr.yp.to/

GIMLI-24-CIPHER has a 256-bit key, a 128-bit nonce, and a 128-bit tag. It is the spiritual successor to the widely used ChaCha20 and has a similar design.

This library also includes an implementation of the hash algorithm GIMLI-24-HASH in both regular hashing and XOF modes.

References: https://gimli.cr.yp.to/

Function Documentation

int gimli24_aead_decrypt	(	unsigned char *	m,
		unsigned long long *	mlen,
		unsigned char *	nsec,
		const unsigned char *	c,
		unsigned long long	clen,
		const unsigned char *	ad,
		unsigned long long	adlen,
		const unsigned char *	npub,
		const unsigned char *	k
	)

Decrypts and authenticates a packet with GIMLI-24 using the full AEAD mode.

Parameters

m	Buffer to receive the plaintext message on output.
mlen	Receives the length of the plaintext message on output.
nsec	Secret nonce - not used by this algorithm.
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 16 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 16 bytes in length.
k	Points to the 32 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: gimli24_aead_encrypt()

int gimli24_aead_encrypt	(	unsigned char *	c,
		unsigned long long *	clen,
		const unsigned char *	m,
		unsigned long long	mlen,
		const unsigned char *	ad,
		unsigned long long	adlen,
		const unsigned char *	nsec,
		const unsigned char *	npub,
		const unsigned char *	k
	)

Encrypts and authenticates a packet with GIMLI-24 using the full AEAD mode.

Parameters

c	Buffer to receive the output.
clen	On exit, set to the length of the output which includes the ciphertext and the 16 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.
nsec	Secret nonce - not used by this algorithm.
npub	Points to the public nonce for the packet which must be 16 bytes in length.
k	Points to the 32 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: gimli24_aead_decrypt()

int gimli24_hash	(	unsigned char *	out,
		const unsigned char *	in,
		unsigned long long	inlen
	)

Hashes a block of input data with GIMLI-24 to generate a hash value.

Parameters

out	Buffer to receive the hash output which must be at least GIMLI24_HASH_SIZE bytes in length.
in	Points to the input data to be hashed.
inlen	Length of the input data in bytes.

Returns: Returns zero on success or -1 if there was an error in the parameters.

void gimli24_hash_absorb	(	gimli24_hash_state_t *	state,
		const unsigned char *	in,
		unsigned long long	inlen
	)

Aborbs more input data into a GIMLI-24-HASH state.

Parameters

state	Hash state to be updated.
in	Points to the input data to be absorbed into the state.
inlen	Length of the input data to be absorbed into the state.

See Also: gimli24_hash_init(), gimli24_hash_squeeze()

void gimli24_hash_finalize	(	gimli24_hash_state_t *	state,
		unsigned char *	out
	)

Returns the final hash value from a GIMLI-24-HASH hashing operation.

Parameters

state	Hash state to be finalized.
out	Points to the output buffer to receive the hash value.

Note: This is a wrapper around gimli24_hash_squeeze() for a fixed length of GIMLI24_HASH_SIZE bytes.

See Also: gimli24_hash_init(), gimli24_hash_absorb()

void gimli24_hash_init ( gimli24_hash_state_t * state )

Initializes the state for a GIMLI-24-HASH hashing operation.

Parameters

state Hash state to be initialized.

See Also: gimli24_hash_absorb(), gimli24_hash_squeeze(), gimli24_hash()

void gimli24_hash_squeeze	(	gimli24_hash_state_t *	state,
		unsigned char *	out,
		unsigned long long	outlen
	)

Squeezes output data from an GIMLI-24-HASH state.

Parameters

state	Hash state to squeeze the output data from.
out	Points to the output buffer to receive the squeezed data.
outlen	Number of bytes of data to squeeze out of the state.

See Also: gimli24_hash_init(), gimli24_hash_absorb()

Variable Documentation

aead_hash_algorithm_t const gimli24_hash_algorithm

Meta-information block for the GIMLI-24-HASH algorithm.

This meta-information block can also be used in XOF mode.

Data Structures

Macros

Functions

Variables

Detailed Description

Function Documentation

Variable Documentation