Contiki-NG
ccm.c
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1 /*
2  * Original file:
3  * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
4  * All rights reserved.
5  *
6  * Port to Contiki:
7  * Copyright (c) 2013, ADVANSEE - http://www.advansee.com/
8  * All rights reserved.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  * notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  * notice, this list of conditions and the following disclaimer in the
17  * documentation and/or other materials provided with the distribution.
18  *
19  * 3. Neither the name of the copyright holder nor the names of its
20  * contributors may be used to endorse or promote products derived
21  * from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
25  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
26  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
27  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
28  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
30  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
32  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
33  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
34  * OF THE POSSIBILITY OF SUCH DAMAGE.
35  */
36 /**
37  * \addtogroup cc2538-ccm
38  * @{
39  *
40  * \file
41  * Implementation of the cc2538 AES-CCM driver
42  */
43 #include "contiki.h"
44 #include "sys/cc.h"
45 #include "dev/rom-util.h"
46 #include "dev/ccm.h"
47 
48 #include <stdbool.h>
49 #include <stdint.h>
50 /*---------------------------------------------------------------------------*/
51 static uint8_t
52 ccm_auth_crypt_start(uint8_t encrypt, uint8_t len_len, uint8_t key_area,
53  const void *nonce, const void *adata, uint16_t adata_len,
54  const void *data_in, void *data_out, uint16_t data_len,
55  uint8_t mic_len, struct process *process)
56 {
57  uint32_t ctrl;
58  uint32_t iv[AES_IV_LEN / sizeof(uint32_t)];
59 
60  /* Program AES-CCM authentication/crypto operation */
61  ctrl = AES_AES_CTRL_SAVE_CONTEXT | /* Save context */
62  (((MAX(mic_len, 2) - 2) >> 1) << AES_AES_CTRL_CCM_M_S) | /* M */
63  ((len_len - 1) << AES_AES_CTRL_CCM_L_S) | /* L */
64  AES_AES_CTRL_CCM | /* CCM */
65  AES_AES_CTRL_CTR_WIDTH_128 | /* CTR width 128 */
66  AES_AES_CTRL_CTR | /* CTR */
67  (encrypt ? AES_AES_CTRL_DIRECTION_ENCRYPT : 0); /* En/decryption */
68 
69  /* Prepare the crypto initialization vector
70  * Flags: L' = L - 1 */
71  ((uint8_t *)iv)[0] = len_len - 1;
72  /* Nonce */
73  rom_util_memcpy(&((uint8_t *)iv)[CCM_FLAGS_LEN], nonce,
74  CCM_NONCE_LEN_LEN - len_len);
75  /* Initialize counter to 0 */
76  rom_util_memset(&((uint8_t *)iv)[AES_IV_LEN - len_len], 0, len_len);
77 
78  return aes_auth_crypt_start(ctrl, key_area, iv, adata, adata_len,
79  data_in, data_out, data_len, process);
80 }
81 /*---------------------------------------------------------------------------*/
82 static uint8_t
83 ccm_auth_crypt_get_result(const void *cdata, uint16_t cdata_len,
84  void *mic, uint8_t mic_len)
85 {
86  uint32_t tag[AES_TAG_LEN / sizeof(uint32_t)];
87  uint16_t data_len;
88  uint8_t ret;
89 
90  ret = aes_auth_crypt_get_result(NULL, tag);
91  if(ret != CRYPTO_SUCCESS) {
92  return ret;
93  }
94 
95  if(cdata != NULL) {
96  /* Check MIC */
97  data_len = cdata_len - mic_len;
98  if(rom_util_memcmp(tag, &((const uint8_t *)cdata)[data_len], mic_len)) {
99  ret = AES_AUTHENTICATION_FAILED;
100  }
101  }
102 
103  /* Copy tag to MIC */
104  rom_util_memcpy(mic, tag, mic_len);
105 
106  return ret;
107 }
108 /*---------------------------------------------------------------------------*/
109 uint8_t
110 ccm_auth_encrypt_start(uint8_t len_len, uint8_t key_area, const void *nonce,
111  const void *adata, uint16_t adata_len, const void *pdata,
112  uint16_t pdata_len, void *cdata, uint8_t mic_len,
113  struct process *process)
114 {
115  return ccm_auth_crypt_start(true, len_len, key_area, nonce, adata, adata_len,
116  pdata, cdata, pdata_len, mic_len, process);
117 }
118 /*---------------------------------------------------------------------------*/
119 uint8_t
120 ccm_auth_encrypt_get_result(void *mic, uint8_t mic_len)
121 {
122  return ccm_auth_crypt_get_result(NULL, 0, mic, mic_len);
123 }
124 /*---------------------------------------------------------------------------*/
125 uint8_t
126 ccm_auth_decrypt_start(uint8_t len_len, uint8_t key_area, const void *nonce,
127  const void *adata, uint16_t adata_len, const void *cdata,
128  uint16_t cdata_len, void *pdata, uint8_t mic_len,
129  struct process *process)
130 {
131  uint16_t data_len = cdata_len - mic_len;
132 
133  return ccm_auth_crypt_start(false, len_len, key_area, nonce, adata, adata_len,
134  cdata, pdata, data_len, mic_len, process);
135 }
136 /*---------------------------------------------------------------------------*/
137 uint8_t
138 ccm_auth_decrypt_get_result(const void *cdata, uint16_t cdata_len,
139  void *mic, uint8_t mic_len)
140 __attribute__ ((alias("ccm_auth_crypt_get_result")));
141 
142 /** @} */
#define AES_AES_CTRL_SAVE_CONTEXT
Auth.
Definition: aes.h:273
#define AES_AES_CTRL_CCM
AES-CCM mode.
Definition: aes.h:279
#define AES_AES_CTRL_CCM_L_S
CCM length field width shift.
Definition: aes.h:278
uint8_t aes_auth_crypt_get_result(void *iv, void *tag)
Gets the result of the AES authentication/crypto operation.
Definition: aes.c:275
uint8_t ccm_auth_encrypt_get_result(void *mic, uint8_t mic_len)
Gets the result of the CCM authentication and encryption operation.
Definition: ccm.c:120
#define AES_AES_CTRL_DIRECTION_ENCRYPT
Encrypt.
Definition: aes.h:297
uint8_t ccm_auth_decrypt_get_result(const void *cdata, uint16_t cdata_len, void *mic, uint8_t mic_len)
Gets the result of the CCM authentication checking and decryption operation.
uint8_t ccm_auth_decrypt_start(uint8_t len_len, uint8_t key_area, const void *nonce, const void *adata, uint16_t adata_len, const void *cdata, uint16_t cdata_len, void *pdata, uint8_t mic_len, struct process *process)
Starts a CCM authentication checking and decryption operation.
Definition: ccm.c:126
uint8_t aes_auth_crypt_start(uint32_t ctrl, uint8_t key_area, const void *iv, const void *adata, uint16_t adata_len, const void *data_in, void *data_out, uint16_t data_len, struct process *process)
Starts an AES authentication/crypto operation.
Definition: aes.c:156
#define AES_AES_CTRL_CCM_M_S
CCM auth.
Definition: aes.h:276
Header file for the cc2538 ROM utility function library driver.
#define AES_AES_CTRL_CTR
AES-CTR mode.
Definition: aes.h:290
Default definitions of C compiler quirk work-arounds.
uint8_t ccm_auth_encrypt_start(uint8_t len_len, uint8_t key_area, const void *nonce, const void *adata, uint16_t adata_len, const void *pdata, uint16_t pdata_len, void *cdata, uint8_t mic_len, struct process *process)
Starts a CCM authentication and encryption operation.
Definition: ccm.c:110
Header file for the cc2538 AES-CCM driver.
#define AES_AES_CTRL_CTR_WIDTH_128
CTR counter width: 128 bits.
Definition: aes.h:285