include/uboot_aes.h

   1 /* SPDX-License-Identifier: GPL-2.0+ */
   2 /*
   3  * Copyright (c) 2011 The Chromium OS Authors.
   4  * (C) Copyright 2010 - 2011 NVIDIA Corporation <www.nvidia.com>
   5  */
   6
   7 #ifndef _AES_REF_H_
   8 #define _AES_REF_H_
   9
  10 #ifdef USE_HOSTCC
  11 /* Define compat stuff for use in fw_* tools. */
  12 typedef unsigned char u8;
  13 typedef unsigned int u32;
  14 #define debug(...) do {} while (0)
  15 #endif
  16
  17 /*
  18  * AES encryption library, with small code size, supporting only 128-bit AES
  19  *
  20  * AES is a stream cipher which works a block at a time, with each block
  21  * in this case being AES_BLOCK_LENGTH bytes.
  22  */
  23
  24 enum {
  25         AES_STATECOLS   = 4,    /* columns in the state & expanded key */
  26         AES128_KEYCOLS  = 4,    /* columns in a key for aes128 */
  27         AES192_KEYCOLS  = 6,    /* columns in a key for aes128 */
  28         AES256_KEYCOLS  = 8,    /* columns in a key for aes128 */
  29         AES128_ROUNDS   = 10,   /* rounds in encryption for aes128 */
  30         AES192_ROUNDS   = 12,   /* rounds in encryption for aes192 */
  31         AES256_ROUNDS   = 14,   /* rounds in encryption for aes256 */
  32         AES128_KEY_LENGTH       = 128 / 8,
  33         AES192_KEY_LENGTH       = 192 / 8,
  34         AES256_KEY_LENGTH       = 256 / 8,
  35         AES128_EXPAND_KEY_LENGTH = 4 * AES_STATECOLS * (AES128_ROUNDS + 1),
  36         AES192_EXPAND_KEY_LENGTH = 4 * AES_STATECOLS * (AES192_ROUNDS + 1),
  37         AES256_EXPAND_KEY_LENGTH = 4 * AES_STATECOLS * (AES256_ROUNDS + 1),
  38         AES_BLOCK_LENGTH        = 128 / 8,
  39 };
  40
  41 /**
  42  * aes_expand_key() - Expand the AES key
  43  *
  44  * Expand a key into a key schedule, which is then used for the other
  45  * operations.
  46  *
  47  * @key         Key
  48  * @key_size    Size of the key (in bits)
  49  * @expkey      Buffer to place expanded key, AES_EXPAND_KEY_LENGTH
  50  */
  51 void aes_expand_key(u8 *key, u32 key_size, u8 *expkey);
  52
  53 /**
  54  * aes_encrypt() - Encrypt single block of data with AES 128
  55  *
  56  * @key_size    Size of the aes key (in bits)
  57  * @in          Input data
  58  * @expkey      Expanded key to use for encryption (from aes_expand_key())
  59  * @out         Output data
  60  */
  61 void aes_encrypt(u32 key_size, u8 *in, u8 *expkey, u8 *out);
  62
  63 /**
  64  * aes_decrypt() - Decrypt single block of data with AES 128
  65  *
  66  * @key_size    Size of the aes key (in bits)
  67  * @in          Input data
  68  * @expkey      Expanded key to use for decryption (from aes_expand_key())
  69  * @out         Output data
  70  */
  71 void aes_decrypt(u32 key_size, u8 *in, u8 *expkey, u8 *out);
  72
  73 /**
  74  * Apply chain data to the destination using EOR
  75  *
  76  * Each array is of length AES_BLOCK_LENGTH.
  77  *
  78  * @cbc_chain_data      Chain data
  79  * @src                 Source data
  80  * @dst                 Destination data, which is modified here
  81  */
  82 void aes_apply_cbc_chain_data(u8 *cbc_chain_data, u8 *src, u8 *dst);
  83
  84 /**
  85  * aes_cbc_encrypt_blocks() - Encrypt multiple blocks of data with AES CBC.
  86  *
  87  * @key_size            Size of the aes key (in bits)
  88  * @key_exp             Expanded key to use
  89  * @iv                  Initialization vector
  90  * @src                 Source data to encrypt
  91  * @dst                 Destination buffer
  92  * @num_aes_blocks      Number of AES blocks to encrypt
  93  */
  94 void aes_cbc_encrypt_blocks(u32 key_size, u8 *key_exp, u8 *iv, u8 *src, u8 *dst,
  95                             u32 num_aes_blocks);
  96
  97 /**
  98  * Decrypt multiple blocks of data with AES CBC.
  99  *
 100  * @key_size            Size of the aes key (in bits)
 101  * @key_exp             Expanded key to use
 102  * @iv                  Initialization vector
 103  * @src                 Source data to decrypt
 104  * @dst                 Destination buffer
 105  * @num_aes_blocks      Number of AES blocks to decrypt
 106  */
 107 void aes_cbc_decrypt_blocks(u32 key_size, u8 *key_exp, u8 *iv, u8 *src, u8 *dst,
 108                             u32 num_aes_blocks);
 109
 110 #endif /* _AES_REF_H_ */