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 *ctr)
 Increment counter block. More...
 

Detailed Description

Galois/Counter Mode (GCM)

License

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

Copyright (C) 2010-2024 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
2.4.4

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]contextPointer to the GCM context
[in]ivInitialization vector
[in]ivLenLength of the initialization vector
[in]aAdditional authenticated data
[in]aLenLength of the additional data
[in]cCiphertext to be decrypted
[out]pPlaintext resulting from the decryption
[in]lengthTotal number of data bytes to be decrypted
[in]tAuthentication tag
[in]tLenLength of the authentication tag
Returns
Error code

Make sure the GCM context is valid

Make sure the GCM context is valid

Definition at line 361 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]contextPointer to the GCM context
[in]ivInitialization vector
[in]ivLenLength of the initialization vector
[in]aAdditional authenticated data
[in]aLenLength of the additional data
[in]pPlaintext to be encrypted
[out]cCiphertext resulting from the encryption
[in]lengthTotal number of data bytes to be encrypted
[out]tAuthentication tag
[in]tLenLength of the authentication tag
Returns
Error code

Definition at line 214 of file gcm.c.

◆ gcmIncCounter()

void gcmIncCounter ( uint8_t *  ctr)

Increment counter block.

Parameters
[in,out]ctrPointer to the counter block

Definition at line 614 of file gcm.c.

◆ gcmInit()

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

Initialize GCM context.

Parameters
[in]contextPointer to the GCM context
[in]cipherAlgoCipher algorithm
[in]cipherContextPointer 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]contextPointer to the GCM context
[in,out]x16-byte block to be multiplied by H

Definition at line 508 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]xBlock resulting from the XOR operation
[in]aFirst block
[in]bSecond block
[in]nSize of the block

Definition at line 597 of file gcm.c.