gcm.h
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1 /**
2  * @file gcm.h
3  * @brief Galois/Counter Mode (GCM)
4  *
5  * @section License
6  *
7  * Copyright (C) 2010-2018 Oryx Embedded SARL. All rights reserved.
8  *
9  * This file is part of CycloneCrypto Open.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License
13  * as published by the Free Software Foundation; either version 2
14  * of the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software Foundation,
23  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
24  *
25  * @author Oryx Embedded SARL (www.oryx-embedded.com)
26  * @version 1.9.0
27  **/
28 
29 #ifndef _GCM_H
30 #define _GCM_H
31 
32 //Dependencies
33 #include "core/crypto.h"
34 
35 //C++ guard
36 #ifdef __cplusplus
37  extern "C" {
38 #endif
39 
40 
41 /**
42  * @brief GCM context
43  **/
44 
45 typedef struct
46 {
47  const CipherAlgo *cipherAlgo; ///<Cipher algorithm
48  void *cipherContext; ///<Cipher algorithm context
49  uint32_t m[16][4]; ///<Precalculated table
50 } GcmContext;
51 
52 
53 //GCM related functions
54 error_t gcmInit(GcmContext *context, const CipherAlgo *cipherAlgo,
55  void *cipherContext);
56 
57 error_t gcmEncrypt(GcmContext *context, const uint8_t *iv,
58  size_t ivLen, const uint8_t *a, size_t aLen, const uint8_t *p,
59  uint8_t *c, size_t length, uint8_t *t, size_t tLen);
60 
61 error_t gcmDecrypt(GcmContext *context, const uint8_t *iv,
62  size_t ivLen, const uint8_t *a, size_t aLen, const uint8_t *c,
63  uint8_t *p, size_t length, const uint8_t *t, size_t tLen);
64 
65 void gcmMul(GcmContext *context, uint8_t *x);
66 void gcmXorBlock(uint8_t *x, const uint8_t *a, const uint8_t *b, size_t n);
67 void gcmIncCounter(uint8_t *x);
68 
69 //C++ guard
70 #ifdef __cplusplus
71  }
72 #endif
73 
74 #endif
void gcmMul(GcmContext *context, uint8_t *x)
Multiplication operation in GF(2^128)
Definition: gcm.c:482
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.
Definition: gcm.c:335
uint8_t c
Definition: ndp.h:510
void gcmXorBlock(uint8_t *x, const uint8_t *a, const uint8_t *b, size_t n)
XOR operation.
Definition: gcm.c:551
void gcmIncCounter(uint8_t *x)
Increment counter block.
Definition: gcm.c:568
uint8_t p
Definition: ndp.h:295
General definitions for cryptographic algorithms.
Common interface for encryption algorithms.
Definition: crypto.h:1073
uint8_t m
Definition: ndp.h:299
uint8_t a
Definition: ndp.h:407
error_t gcmInit(GcmContext *context, const CipherAlgo *cipherAlgo, void *cipherContext)
Initialize GCM context.
Definition: gcm.c:76
GCM context.
Definition: gcm.h:45
const CipherAlgo * cipherAlgo
Cipher algorithm.
Definition: gcm.h:47
void * cipherContext
Cipher algorithm context.
Definition: gcm.h:48
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.
Definition: gcm.c:188
error_t
Error codes.
Definition: error.h:40
uint8_t length
Definition: dtls_misc.h:140
uint8_t n
uint8_t b[6]
Definition: dtls_misc.h:130