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_ */ 111