1  /*
 2   * (c) 2015-2017 Marcos Del Sol Vives
 3   * (c) 2016      javiMaD
 4   *
 5   * SPDX-License-Identifier: MIT
 6   */
 7  
 8  #ifndef HAVE_NFC3D_DRBG_H
 9  #define HAVE_NFC3D_DRBG_H
10  
11  #include "nfc3d/crypto.h"
12  #include <stdbool.h>
13  #include <stdint.h>
14  
15  #define NFC3D_DRBG_MAX_SEED_SIZE 480 /* Hardcoded max size in 3DS NFC module */
16  #define NFC3D_DRBG_OUTPUT_SIZE 32    /* Every iteration generates 32 bytes */
17  
18  typedef struct
19  {
20  	nrf_crypto_hmac_context_t hmacCtx;
21  	bool used;
22  	uint16_t iteration;
23  
24  	uint8_t buffer[sizeof(uint16_t) + NFC3D_DRBG_MAX_SEED_SIZE];
25  	size_t bufferSize;
26  
27  	const uint8_t* hmacKey;
28  	size_t hmacKeySize;
29  } nfc3d_drbg_ctx;
30  
31  void nfc3d_drbg_init(nfc3d_drbg_ctx* ctx, const uint8_t* hmacKey, size_t hmacKeySize, const uint8_t* seed, size_t seedSize);
32  void nfc3d_drbg_step(nfc3d_drbg_ctx* ctx, uint8_t* output);
33  void nfc3d_drbg_cleanup(nfc3d_drbg_ctx* ctx);
34  void nfc3d_drbg_generate_bytes(const uint8_t* hmacKey, size_t hmacKeySize, const uint8_t* seed, size_t seedSize, uint8_t* output, size_t outputSize);
35  
36  #endif