From 5b1a5451d5aa3f440da071d303bc8064ae5571b9 Mon Sep 17 00:00:00 2001 From: Yen Lin Date: Thu, 5 Apr 2012 11:54:58 +0000 Subject: Add AES crypto library Add support for AES using an implementation from Karl Malbrain. This offers small code size (around 5KB on ARM) and supports 128-bit AES only. Signed-off-by: Yen Lin Signed-off-by: Simon Glass Signed-off-by: Tom Warren --- include/aes.h | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) create mode 100644 include/aes.h (limited to 'include/aes.h') diff --git a/include/aes.h b/include/aes.h new file mode 100644 index 0000000000..41b0db29c1 --- /dev/null +++ b/include/aes.h @@ -0,0 +1,70 @@ +/* + * Copyright (c) 2011 The Chromium OS Authors. + * (C) Copyright 2010 - 2011 NVIDIA Corporation + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#ifndef _AES_REF_H_ +#define _AES_REF_H_ + +/* + * AES encryption library, with small code size, supporting only 128-bit AES + * + * AES is a stream cipher which works a block at a time, with each block + * in this case being AES_KEY_LENGTH bytes. + */ + +enum { + AES_STATECOLS = 4, /* columns in the state & expanded key */ + AES_KEYCOLS = 4, /* columns in a key */ + AES_ROUNDS = 10, /* rounds in encryption */ + + AES_KEY_LENGTH = 128 / 8, + AES_EXPAND_KEY_LENGTH = 4 * AES_STATECOLS * (AES_ROUNDS + 1), +}; + +/** + * Expand a key into a key schedule, which is then used for the other + * operations. + * + * \param key Key, of length AES_KEY_LENGTH bytes + * \param expkey Buffer to place expanded key, AES_EXPAND_KEY_LENGTH + */ +void aes_expand_key(u8 *key, u8 *expkey); + +/** + * Encrypt a single block of data + * + * in Input data + * expkey Expanded key to use for encryption (from aes_expand_key()) + * out Output data + */ +void aes_encrypt(u8 *in, u8 *expkey, u8 *out); + +/** + * Decrypt a single block of data + * + * in Input data + * expkey Expanded key to use for decryption (from aes_expand_key()) + * out Output data + */ +void aes_decrypt(u8 *in, u8 *expkey, u8 *out); + +#endif /* _AES_REF_H_ */ -- cgit v1.2.1