gcm.h File Reference

Galois/Counter Mode (GCM) More...

#include "core/crypto.h"

Go to the source code of this file.

Data Structures
struct	GcmContext
	GCM context. More...

Macros
#define	GCM_TABLE_W   4
#define	GCM_TABLE_N   16
#define	GCM_REVERSE_BITS(n)   reverseInt4(n)

Functions
error_t	gcmInit (GcmContext *context, const CipherAlgo *cipherAlgo, void *cipherContext)
	Initialize GCM context. More...
error_t	gcmEncrypt (GcmContext *context, const uint8_t *iv, size_t ivLen, const uint8_t *a, size_t aLen, const uint8_t *p, uint8_t *c, size_t length, uint8_t *t, size_t tLen)
	Authenticated encryption using GCM. More...
error_t	gcmDecrypt (GcmContext *context, const uint8_t *iv, size_t ivLen, const uint8_t *a, size_t aLen, const uint8_t *c, uint8_t *p, size_t length, const uint8_t *t, size_t tLen)
	Authenticated decryption using GCM. More...
void	gcmMul (GcmContext *context, uint8_t *x)
	Multiplication operation in GF(2^128) More...
void	gcmXorBlock (uint8_t *x, const uint8_t *a, const uint8_t *b, size_t n)
	XOR operation. More...
void	gcmIncCounter (uint8_t *x)
	Increment counter block. More...

Detailed Description

Galois/Counter Mode (GCM)

License

SPDX-License-Identifier: GPL-2.0-or-later

Copyright (C) 2010-2023 Oryx Embedded SARL. All rights reserved.

This file is part of CycloneCRYPTO Open.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.

Author

Oryx Embedded SARL (www.oryx-embedded.com)

Version

2.2.4

Definition in file gcm.h.

Macro Definition Documentation

GCM_REVERSE_BITS

#define GCM_REVERSE_BITS

(

n

)

reverseInt4(n)

Definition at line 47 of file gcm.h.

GCM_TABLE_N

#define GCM_TABLE_N   16

Definition at line 46 of file gcm.h.

GCM_TABLE_W

#define GCM_TABLE_W   4

Definition at line 39 of file gcm.h.

Function Documentation

gcmDecrypt()

error_t gcmDecrypt	(	GcmContext *	context,
		const uint8_t *	iv,
		size_t	ivLen,
		const uint8_t *	a,
		size_t	aLen,
		const uint8_t *	c,
		uint8_t *	p,
		size_t	length,
		const uint8_t *	t,
		size_t	tLen
	)

Authenticated decryption using GCM.

Parameters

[in]	context	Pointer to the GCM context
[in]	iv	Initialization vector
[in]	ivLen	Length of the initialization vector
[in]	a	Additional authenticated data
[in]	aLen	Length of the additional data
[in]	c	Ciphertext to be decrypted
[out]	p	Plaintext resulting from the decryption
[in]	length	Total number of data bytes to be decrypted
[in]	t	Authentication tag
[in]	tLen	Length of the authentication tag

Returns

Error code

Make sure the GCM context is valid

Make sure the GCM context is valid

Make sure the GCM context is valid

Definition at line 357 of file gcm.c.

gcmEncrypt()

error_t gcmEncrypt	(	GcmContext *	context,
		const uint8_t *	iv,
		size_t	ivLen,
		const uint8_t *	a,
		size_t	aLen,
		const uint8_t *	p,
		uint8_t *	c,
		size_t	length,
		uint8_t *	t,
		size_t	tLen
	)

Authenticated encryption using GCM.

Parameters

[in]	context	Pointer to the GCM context
[in]	iv	Initialization vector
[in]	ivLen	Length of the initialization vector
[in]	a	Additional authenticated data
[in]	aLen	Length of the additional data
[in]	p	Plaintext to be encrypted
[out]	c	Ciphertext resulting from the encryption
[in]	length	Total number of data bytes to be encrypted
[out]	t	Authentication tag
[in]	tLen	Length of the authentication tag

Returns

Error code

Definition at line 210 of file gcm.c.

gcmIncCounter()

void gcmIncCounter

(

uint8_t *

x

)

Increment counter block.

Parameters

[in,out]

x

Pointer to the counter block

Definition at line 610 of file gcm.c.

gcmInit()

error_t gcmInit	(	GcmContext *	context,
		const CipherAlgo *	cipherAlgo,
		void *	cipherContext
	)

Initialize GCM context.

Parameters

[in]	context	Pointer to the GCM context
[in]	cipherAlgo	Cipher algorithm
[in]	cipherContext	Pointer to the cipher algorithm context

Returns

Error code

Definition at line 99 of file gcm.c.

gcmMul()

void gcmMul	(	GcmContext *	context,
		uint8_t *	x
	)

Multiplication operation in GF(2^128)

Parameters

[in]	context	Pointer to the GCM context
[in,out]	x	16-byte block to be multiplied by H

Definition at line 504 of file gcm.c.

gcmXorBlock()

void gcmXorBlock	(	uint8_t *	x,
		const uint8_t *	a,
		const uint8_t *	b,
		size_t	n
	)

XOR operation.

Parameters

[out]	x	Block resulting from the XOR operation
[in]	a	First block
[in]	b	Second block
[in]	n	Size of the block

Definition at line 593 of file gcm.c.