git.zerfleddert.de Git - proxmark3-svn/blob - common/polarssl/libpcrypto.c

   1 //-----------------------------------------------------------------------------
   2 // Copyright (C) 2018 Merlok
   3 // Copyright (C) 2018 drHatson
   4 //
   5 // This code is licensed to you under the terms of the GNU GPL, version 2 or,
   6 // at your option, any later version. See the LICENSE.txt file for the text of
   7 // the license.
   8 //-----------------------------------------------------------------------------
   9 // crypto commands
  10 //-----------------------------------------------------------------------------
  11
  12 #include "polarssl/libpcrypto.h"
  13 #include <polarssl/aes.h>
  14 #include <polarssl/aes_cmac128.h>
  15
  16 // NIST Special Publication 800-38A \97 Recommendation for block cipher modes of operation: methods and techniques, 2001.
  17 int aes_encode(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *output, int length){
  18         uint8_t iiv[16] = {0};
  19         if (iv)
  20                 memcpy(iiv, iv, 16);
  21
  22         aes_context aes;
  23         aes_init(&aes);
  24         if (aes_setkey_enc(&aes, key, 128))
  25                 return 1;
  26         if (aes_crypt_cbc(&aes, AES_ENCRYPT, length, iiv, input, output))
  27                 return 2;
  28         aes_free(&aes);
  29
  30         return 0;
  31 }
  32
  33 int aes_decode(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *output, int length){
  34         uint8_t iiv[16] = {0};
  35         if (iv)
  36                 memcpy(iiv, iv, 16);
  37
  38         aes_context aes;
  39         aes_init(&aes);
  40         if (aes_setkey_dec(&aes, key, 128))
  41                 return 1;
  42         if (aes_crypt_cbc(&aes, AES_DECRYPT, length, iiv, input, output))
  43                 return 2;
  44         aes_free(&aes);
  45
  46         return 0;
  47 }
  48
  49 // NIST Special Publication 800-38B \97 Recommendation for block cipher modes of operation: The CMAC mode for authentication.
  50 // https://csrc.nist.gov/CSRC/media/Projects/Cryptographic-Standards-and-Guidelines/documents/examples/AES_CMAC.pdf
  51 int aes_cmac(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *mac, int length) {
  52         memset(mac, 0x00, 16);
  53         uint8_t iiv[16] = {0};
  54         if (iv)
  55                 memcpy(iiv, iv, 16);
  56
  57         //  NIST 800-38B
  58         aes_cmac128_context ctx;
  59         aes_cmac128_starts(&ctx, key);
  60         aes_cmac128_update(&ctx, input, length);
  61         aes_cmac128_final(&ctx, mac);
  62
  63         return 0;
  64 }
  65
  66 int aes_cmac8(uint8_t *iv, uint8_t *key, uint8_t *input, uint8_t *mac, int length) {
  67         uint8_t cmac[16] = {0};
  68         memset(mac, 0x00, 8);
  69
  70         int res = aes_cmac(iv, key, input, cmac, length);
  71         if (res)
  72                 return res;
  73
  74         for(int i = 0; i < 8; i++)
  75                 mac[i] = cmac[i * 2 + 1];
  76
  77         return 0;
  78 }