include/uboot_aes.h

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