]> git.dujemihanovic.xyz Git - u-boot.git/commitdiff
Add AES crypto library
authorYen Lin <yelin@nvidia.com>
Thu, 5 Apr 2012 11:54:58 +0000 (11:54 +0000)
committerAlbert ARIBAUD <albert.u.boot@aribaud.net>
Tue, 15 May 2012 06:31:37 +0000 (08:31 +0200)
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 <yelin@nvidia.com>
Signed-off-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Tom Warren <twarren@nvidia.com>
include/aes.h [new file with mode: 0644]
lib/Makefile
lib/aes.c [new file with mode: 0644]

diff --git a/include/aes.h b/include/aes.h
new file mode 100644 (file)
index 0000000..41b0db2
--- /dev/null
@@ -0,0 +1,70 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2010 - 2011 NVIDIA Corporation <www.nvidia.com>
+ *
+ * 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_ */
index a0fec60a136a07388f4cf4d9b8c216b211c02881..1e8478f0312e1a4f9d81513a2ad9ec06272a70cf 100644 (file)
@@ -28,6 +28,7 @@ LIB   = $(obj)libgeneric.o
 ifndef CONFIG_SPL_BUILD
 COBJS-$(CONFIG_ADDR_MAP) += addr_map.o
 COBJS-$(CONFIG_BCH) += bch.o
+COBJS-$(CONFIG_AES) += aes.o
 COBJS-$(CONFIG_BZIP2) += bzlib.o
 COBJS-$(CONFIG_BZIP2) += bzlib_crctable.o
 COBJS-$(CONFIG_BZIP2) += bzlib_decompress.o
diff --git a/lib/aes.c b/lib/aes.c
new file mode 100644 (file)
index 0000000..7da9edb
--- /dev/null
+++ b/lib/aes.c
@@ -0,0 +1,598 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * (C) Copyright 2011 NVIDIA Corporation www.nvidia.com
+ *
+ * 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
+ */
+
+/*
+ * advanced encryption standard
+ * author: karl malbrain, malbrain@yahoo.com
+ *
+ * This work, including the source code, documentation
+ * and related data, is placed into the public domain.
+ *
+ * The orginal author is Karl Malbrain.
+ *
+ * THIS SOFTWARE IS PROVIDED AS-IS WITHOUT WARRANTY
+ * OF ANY KIND, NOT EVEN THE IMPLIED WARRANTY OF
+ * MERCHANTABILITY. THE AUTHOR OF THIS SOFTWARE,
+ * ASSUMES _NO_ RESPONSIBILITY FOR ANY CONSEQUENCE
+ * RESULTING FROM THE USE, MODIFICATION, OR
+ * REDISTRIBUTION OF THIS SOFTWARE.
+*/
+
+#include <common.h>
+#include "aes.h"
+
+/* forward s-box */
+static const u8 sbox[256] = {
+       0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5,
+       0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76,
+       0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0,
+       0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0,
+       0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc,
+       0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15,
+       0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a,
+       0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75,
+       0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0,
+       0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84,
+       0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b,
+       0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf,
+       0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85,
+       0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8,
+       0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5,
+       0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2,
+       0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17,
+       0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73,
+       0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88,
+       0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb,
+       0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c,
+       0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79,
+       0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9,
+       0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08,
+       0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6,
+       0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a,
+       0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e,
+       0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e,
+       0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94,
+       0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf,
+       0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68,
+       0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16
+};
+
+/* inverse s-box */
+static const u8 inv_sbox[256] = {
+       0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38,
+       0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb,
+       0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87,
+       0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb,
+       0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d,
+       0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e,
+       0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2,
+       0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25,
+       0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16,
+       0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92,
+       0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda,
+       0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84,
+       0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a,
+       0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06,
+       0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02,
+       0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b,
+       0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea,
+       0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73,
+       0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85,
+       0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e,
+       0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89,
+       0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b,
+       0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20,
+       0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4,
+       0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31,
+       0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f,
+       0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d,
+       0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef,
+       0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0,
+       0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61,
+       0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26,
+       0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d
+};
+
+/* combined Xtimes2[Sbox[]] */
+static const u8 x2_sbox[256] = {
+       0xc6, 0xf8, 0xee, 0xf6, 0xff, 0xd6, 0xde, 0x91,
+       0x60, 0x02, 0xce, 0x56, 0xe7, 0xb5, 0x4d, 0xec,
+       0x8f, 0x1f, 0x89, 0xfa, 0xef, 0xb2, 0x8e, 0xfb,
+       0x41, 0xb3, 0x5f, 0x45, 0x23, 0x53, 0xe4, 0x9b,
+       0x75, 0xe1, 0x3d, 0x4c, 0x6c, 0x7e, 0xf5, 0x83,
+       0x68, 0x51, 0xd1, 0xf9, 0xe2, 0xab, 0x62, 0x2a,
+       0x08, 0x95, 0x46, 0x9d, 0x30, 0x37, 0x0a, 0x2f,
+       0x0e, 0x24, 0x1b, 0xdf, 0xcd, 0x4e, 0x7f, 0xea,
+       0x12, 0x1d, 0x58, 0x34, 0x36, 0xdc, 0xb4, 0x5b,
+       0xa4, 0x76, 0xb7, 0x7d, 0x52, 0xdd, 0x5e, 0x13,
+       0xa6, 0xb9, 0x00, 0xc1, 0x40, 0xe3, 0x79, 0xb6,
+       0xd4, 0x8d, 0x67, 0x72, 0x94, 0x98, 0xb0, 0x85,
+       0xbb, 0xc5, 0x4f, 0xed, 0x86, 0x9a, 0x66, 0x11,
+       0x8a, 0xe9, 0x04, 0xfe, 0xa0, 0x78, 0x25, 0x4b,
+       0xa2, 0x5d, 0x80, 0x05, 0x3f, 0x21, 0x70, 0xf1,
+       0x63, 0x77, 0xaf, 0x42, 0x20, 0xe5, 0xfd, 0xbf,
+       0x81, 0x18, 0x26, 0xc3, 0xbe, 0x35, 0x88, 0x2e,
+       0x93, 0x55, 0xfc, 0x7a, 0xc8, 0xba, 0x32, 0xe6,
+       0xc0, 0x19, 0x9e, 0xa3, 0x44, 0x54, 0x3b, 0x0b,
+       0x8c, 0xc7, 0x6b, 0x28, 0xa7, 0xbc, 0x16, 0xad,
+       0xdb, 0x64, 0x74, 0x14, 0x92, 0x0c, 0x48, 0xb8,
+       0x9f, 0xbd, 0x43, 0xc4, 0x39, 0x31, 0xd3, 0xf2,
+       0xd5, 0x8b, 0x6e, 0xda, 0x01, 0xb1, 0x9c, 0x49,
+       0xd8, 0xac, 0xf3, 0xcf, 0xca, 0xf4, 0x47, 0x10,
+       0x6f, 0xf0, 0x4a, 0x5c, 0x38, 0x57, 0x73, 0x97,
+       0xcb, 0xa1, 0xe8, 0x3e, 0x96, 0x61, 0x0d, 0x0f,
+       0xe0, 0x7c, 0x71, 0xcc, 0x90, 0x06, 0xf7, 0x1c,
+       0xc2, 0x6a, 0xae, 0x69, 0x17, 0x99, 0x3a, 0x27,
+       0xd9, 0xeb, 0x2b, 0x22, 0xd2, 0xa9, 0x07, 0x33,
+       0x2d, 0x3c, 0x15, 0xc9, 0x87, 0xaa, 0x50, 0xa5,
+       0x03, 0x59, 0x09, 0x1a, 0x65, 0xd7, 0x84, 0xd0,
+       0x82, 0x29, 0x5a, 0x1e, 0x7b, 0xa8, 0x6d, 0x2c
+};
+
+/* combined Xtimes3[Sbox[]] */
+static const u8 x3_sbox[256] = {
+       0xa5, 0x84, 0x99, 0x8d, 0x0d, 0xbd, 0xb1, 0x54,
+       0x50, 0x03, 0xa9, 0x7d, 0x19, 0x62, 0xe6, 0x9a,
+       0x45, 0x9d, 0x40, 0x87, 0x15, 0xeb, 0xc9, 0x0b,
+       0xec, 0x67, 0xfd, 0xea, 0xbf, 0xf7, 0x96, 0x5b,
+       0xc2, 0x1c, 0xae, 0x6a, 0x5a, 0x41, 0x02, 0x4f,
+       0x5c, 0xf4, 0x34, 0x08, 0x93, 0x73, 0x53, 0x3f,
+       0x0c, 0x52, 0x65, 0x5e, 0x28, 0xa1, 0x0f, 0xb5,
+       0x09, 0x36, 0x9b, 0x3d, 0x26, 0x69, 0xcd, 0x9f,
+       0x1b, 0x9e, 0x74, 0x2e, 0x2d, 0xb2, 0xee, 0xfb,
+       0xf6, 0x4d, 0x61, 0xce, 0x7b, 0x3e, 0x71, 0x97,
+       0xf5, 0x68, 0x00, 0x2c, 0x60, 0x1f, 0xc8, 0xed,
+       0xbe, 0x46, 0xd9, 0x4b, 0xde, 0xd4, 0xe8, 0x4a,
+       0x6b, 0x2a, 0xe5, 0x16, 0xc5, 0xd7, 0x55, 0x94,
+       0xcf, 0x10, 0x06, 0x81, 0xf0, 0x44, 0xba, 0xe3,
+       0xf3, 0xfe, 0xc0, 0x8a, 0xad, 0xbc, 0x48, 0x04,
+       0xdf, 0xc1, 0x75, 0x63, 0x30, 0x1a, 0x0e, 0x6d,
+       0x4c, 0x14, 0x35, 0x2f, 0xe1, 0xa2, 0xcc, 0x39,
+       0x57, 0xf2, 0x82, 0x47, 0xac, 0xe7, 0x2b, 0x95,
+       0xa0, 0x98, 0xd1, 0x7f, 0x66, 0x7e, 0xab, 0x83,
+       0xca, 0x29, 0xd3, 0x3c, 0x79, 0xe2, 0x1d, 0x76,
+       0x3b, 0x56, 0x4e, 0x1e, 0xdb, 0x0a, 0x6c, 0xe4,
+       0x5d, 0x6e, 0xef, 0xa6, 0xa8, 0xa4, 0x37, 0x8b,
+       0x32, 0x43, 0x59, 0xb7, 0x8c, 0x64, 0xd2, 0xe0,
+       0xb4, 0xfa, 0x07, 0x25, 0xaf, 0x8e, 0xe9, 0x18,
+       0xd5, 0x88, 0x6f, 0x72, 0x24, 0xf1, 0xc7, 0x51,
+       0x23, 0x7c, 0x9c, 0x21, 0xdd, 0xdc, 0x86, 0x85,
+       0x90, 0x42, 0xc4, 0xaa, 0xd8, 0x05, 0x01, 0x12,
+       0xa3, 0x5f, 0xf9, 0xd0, 0x91, 0x58, 0x27, 0xb9,
+       0x38, 0x13, 0xb3, 0x33, 0xbb, 0x70, 0x89, 0xa7,
+       0xb6, 0x22, 0x92, 0x20, 0x49, 0xff, 0x78, 0x7a,
+       0x8f, 0xf8, 0x80, 0x17, 0xda, 0x31, 0xc6, 0xb8,
+       0xc3, 0xb0, 0x77, 0x11, 0xcb, 0xfc, 0xd6, 0x3a
+};
+
+/*
+ * modular multiplication tables based on:
+ *
+ * Xtime2[x] = (x & 0x80 ? 0x1b : 0) ^ (x + x)
+ * Xtime3[x] = x^Xtime2[x];
+ */
+static const u8 x_time_9[256] = {
+       0x00, 0x09, 0x12, 0x1b, 0x24, 0x2d, 0x36, 0x3f,
+       0x48, 0x41, 0x5a, 0x53, 0x6c, 0x65, 0x7e, 0x77,
+       0x90, 0x99, 0x82, 0x8b, 0xb4, 0xbd, 0xa6, 0xaf,
+       0xd8, 0xd1, 0xca, 0xc3, 0xfc, 0xf5, 0xee, 0xe7,
+       0x3b, 0x32, 0x29, 0x20, 0x1f, 0x16, 0x0d, 0x04,
+       0x73, 0x7a, 0x61, 0x68, 0x57, 0x5e, 0x45, 0x4c,
+       0xab, 0xa2, 0xb9, 0xb0, 0x8f, 0x86, 0x9d, 0x94,
+       0xe3, 0xea, 0xf1, 0xf8, 0xc7, 0xce, 0xd5, 0xdc,
+       0x76, 0x7f, 0x64, 0x6d, 0x52, 0x5b, 0x40, 0x49,
+       0x3e, 0x37, 0x2c, 0x25, 0x1a, 0x13, 0x08, 0x01,
+       0xe6, 0xef, 0xf4, 0xfd, 0xc2, 0xcb, 0xd0, 0xd9,
+       0xae, 0xa7, 0xbc, 0xb5, 0x8a, 0x83, 0x98, 0x91,
+       0x4d, 0x44, 0x5f, 0x56, 0x69, 0x60, 0x7b, 0x72,
+       0x05, 0x0c, 0x17, 0x1e, 0x21, 0x28, 0x33, 0x3a,
+       0xdd, 0xd4, 0xcf, 0xc6, 0xf9, 0xf0, 0xeb, 0xe2,
+       0x95, 0x9c, 0x87, 0x8e, 0xb1, 0xb8, 0xa3, 0xaa,
+       0xec, 0xe5, 0xfe, 0xf7, 0xc8, 0xc1, 0xda, 0xd3,
+       0xa4, 0xad, 0xb6, 0xbf, 0x80, 0x89, 0x92, 0x9b,
+       0x7c, 0x75, 0x6e, 0x67, 0x58, 0x51, 0x4a, 0x43,
+       0x34, 0x3d, 0x26, 0x2f, 0x10, 0x19, 0x02, 0x0b,
+       0xd7, 0xde, 0xc5, 0xcc, 0xf3, 0xfa, 0xe1, 0xe8,
+       0x9f, 0x96, 0x8d, 0x84, 0xbb, 0xb2, 0xa9, 0xa0,
+       0x47, 0x4e, 0x55, 0x5c, 0x63, 0x6a, 0x71, 0x78,
+       0x0f, 0x06, 0x1d, 0x14, 0x2b, 0x22, 0x39, 0x30,
+       0x9a, 0x93, 0x88, 0x81, 0xbe, 0xb7, 0xac, 0xa5,
+       0xd2, 0xdb, 0xc0, 0xc9, 0xf6, 0xff, 0xe4, 0xed,
+       0x0a, 0x03, 0x18, 0x11, 0x2e, 0x27, 0x3c, 0x35,
+       0x42, 0x4b, 0x50, 0x59, 0x66, 0x6f, 0x74, 0x7d,
+       0xa1, 0xa8, 0xb3, 0xba, 0x85, 0x8c, 0x97, 0x9e,
+       0xe9, 0xe0, 0xfb, 0xf2, 0xcd, 0xc4, 0xdf, 0xd6,
+       0x31, 0x38, 0x23, 0x2a, 0x15, 0x1c, 0x07, 0x0e,
+       0x79, 0x70, 0x6b, 0x62, 0x5d, 0x54, 0x4f, 0x46
+};
+
+static const u8 x_time_b[256] = {
+       0x00, 0x0b, 0x16, 0x1d, 0x2c, 0x27, 0x3a, 0x31,
+       0x58, 0x53, 0x4e, 0x45, 0x74, 0x7f, 0x62, 0x69,
+       0xb0, 0xbb, 0xa6, 0xad, 0x9c, 0x97, 0x8a, 0x81,
+       0xe8, 0xe3, 0xfe, 0xf5, 0xc4, 0xcf, 0xd2, 0xd9,
+       0x7b, 0x70, 0x6d, 0x66, 0x57, 0x5c, 0x41, 0x4a,
+       0x23, 0x28, 0x35, 0x3e, 0x0f, 0x04, 0x19, 0x12,
+       0xcb, 0xc0, 0xdd, 0xd6, 0xe7, 0xec, 0xf1, 0xfa,
+       0x93, 0x98, 0x85, 0x8e, 0xbf, 0xb4, 0xa9, 0xa2,
+       0xf6, 0xfd, 0xe0, 0xeb, 0xda, 0xd1, 0xcc, 0xc7,
+       0xae, 0xa5, 0xb8, 0xb3, 0x82, 0x89, 0x94, 0x9f,
+       0x46, 0x4d, 0x50, 0x5b, 0x6a, 0x61, 0x7c, 0x77,
+       0x1e, 0x15, 0x08, 0x03, 0x32, 0x39, 0x24, 0x2f,
+       0x8d, 0x86, 0x9b, 0x90, 0xa1, 0xaa, 0xb7, 0xbc,
+       0xd5, 0xde, 0xc3, 0xc8, 0xf9, 0xf2, 0xef, 0xe4,
+       0x3d, 0x36, 0x2b, 0x20, 0x11, 0x1a, 0x07, 0x0c,
+       0x65, 0x6e, 0x73, 0x78, 0x49, 0x42, 0x5f, 0x54,
+       0xf7, 0xfc, 0xe1, 0xea, 0xdb, 0xd0, 0xcd, 0xc6,
+       0xaf, 0xa4, 0xb9, 0xb2, 0x83, 0x88, 0x95, 0x9e,
+       0x47, 0x4c, 0x51, 0x5a, 0x6b, 0x60, 0x7d, 0x76,
+       0x1f, 0x14, 0x09, 0x02, 0x33, 0x38, 0x25, 0x2e,
+       0x8c, 0x87, 0x9a, 0x91, 0xa0, 0xab, 0xb6, 0xbd,
+       0xd4, 0xdf, 0xc2, 0xc9, 0xf8, 0xf3, 0xee, 0xe5,
+       0x3c, 0x37, 0x2a, 0x21, 0x10, 0x1b, 0x06, 0x0d,
+       0x64, 0x6f, 0x72, 0x79, 0x48, 0x43, 0x5e, 0x55,
+       0x01, 0x0a, 0x17, 0x1c, 0x2d, 0x26, 0x3b, 0x30,
+       0x59, 0x52, 0x4f, 0x44, 0x75, 0x7e, 0x63, 0x68,
+       0xb1, 0xba, 0xa7, 0xac, 0x9d, 0x96, 0x8b, 0x80,
+       0xe9, 0xe2, 0xff, 0xf4, 0xc5, 0xce, 0xd3, 0xd8,
+       0x7a, 0x71, 0x6c, 0x67, 0x56, 0x5d, 0x40, 0x4b,
+       0x22, 0x29, 0x34, 0x3f, 0x0e, 0x05, 0x18, 0x13,
+       0xca, 0xc1, 0xdc, 0xd7, 0xe6, 0xed, 0xf0, 0xfb,
+       0x92, 0x99, 0x84, 0x8f, 0xbe, 0xb5, 0xa8, 0xa3
+};
+
+static const u8 x_time_d[256] = {
+       0x00, 0x0d, 0x1a, 0x17, 0x34, 0x39, 0x2e, 0x23,
+       0x68, 0x65, 0x72, 0x7f, 0x5c, 0x51, 0x46, 0x4b,
+       0xd0, 0xdd, 0xca, 0xc7, 0xe4, 0xe9, 0xfe, 0xf3,
+       0xb8, 0xb5, 0xa2, 0xaf, 0x8c, 0x81, 0x96, 0x9b,
+       0xbb, 0xb6, 0xa1, 0xac, 0x8f, 0x82, 0x95, 0x98,
+       0xd3, 0xde, 0xc9, 0xc4, 0xe7, 0xea, 0xfd, 0xf0,
+       0x6b, 0x66, 0x71, 0x7c, 0x5f, 0x52, 0x45, 0x48,
+       0x03, 0x0e, 0x19, 0x14, 0x37, 0x3a, 0x2d, 0x20,
+       0x6d, 0x60, 0x77, 0x7a, 0x59, 0x54, 0x43, 0x4e,
+       0x05, 0x08, 0x1f, 0x12, 0x31, 0x3c, 0x2b, 0x26,
+       0xbd, 0xb0, 0xa7, 0xaa, 0x89, 0x84, 0x93, 0x9e,
+       0xd5, 0xd8, 0xcf, 0xc2, 0xe1, 0xec, 0xfb, 0xf6,
+       0xd6, 0xdb, 0xcc, 0xc1, 0xe2, 0xef, 0xf8, 0xf5,
+       0xbe, 0xb3, 0xa4, 0xa9, 0x8a, 0x87, 0x90, 0x9d,
+       0x06, 0x0b, 0x1c, 0x11, 0x32, 0x3f, 0x28, 0x25,
+       0x6e, 0x63, 0x74, 0x79, 0x5a, 0x57, 0x40, 0x4d,
+       0xda, 0xd7, 0xc0, 0xcd, 0xee, 0xe3, 0xf4, 0xf9,
+       0xb2, 0xbf, 0xa8, 0xa5, 0x86, 0x8b, 0x9c, 0x91,
+       0x0a, 0x07, 0x10, 0x1d, 0x3e, 0x33, 0x24, 0x29,
+       0x62, 0x6f, 0x78, 0x75, 0x56, 0x5b, 0x4c, 0x41,
+       0x61, 0x6c, 0x7b, 0x76, 0x55, 0x58, 0x4f, 0x42,
+       0x09, 0x04, 0x13, 0x1e, 0x3d, 0x30, 0x27, 0x2a,
+       0xb1, 0xbc, 0xab, 0xa6, 0x85, 0x88, 0x9f, 0x92,
+       0xd9, 0xd4, 0xc3, 0xce, 0xed, 0xe0, 0xf7, 0xfa,
+       0xb7, 0xba, 0xad, 0xa0, 0x83, 0x8e, 0x99, 0x94,
+       0xdf, 0xd2, 0xc5, 0xc8, 0xeb, 0xe6, 0xf1, 0xfc,
+       0x67, 0x6a, 0x7d, 0x70, 0x53, 0x5e, 0x49, 0x44,
+       0x0f, 0x02, 0x15, 0x18, 0x3b, 0x36, 0x21, 0x2c,
+       0x0c, 0x01, 0x16, 0x1b, 0x38, 0x35, 0x22, 0x2f,
+       0x64, 0x69, 0x7e, 0x73, 0x50, 0x5d, 0x4a, 0x47,
+       0xdc, 0xd1, 0xc6, 0xcb, 0xe8, 0xe5, 0xf2, 0xff,
+       0xb4, 0xb9, 0xae, 0xa3, 0x80, 0x8d, 0x9a, 0x97
+};
+
+static const u8 x_time_e[256] = {
+       0x00, 0x0e, 0x1c, 0x12, 0x38, 0x36, 0x24, 0x2a,
+       0x70, 0x7e, 0x6c, 0x62, 0x48, 0x46, 0x54, 0x5a,
+       0xe0, 0xee, 0xfc, 0xf2, 0xd8, 0xd6, 0xc4, 0xca,
+       0x90, 0x9e, 0x8c, 0x82, 0xa8, 0xa6, 0xb4, 0xba,
+       0xdb, 0xd5, 0xc7, 0xc9, 0xe3, 0xed, 0xff, 0xf1,
+       0xab, 0xa5, 0xb7, 0xb9, 0x93, 0x9d, 0x8f, 0x81,
+       0x3b, 0x35, 0x27, 0x29, 0x03, 0x0d, 0x1f, 0x11,
+       0x4b, 0x45, 0x57, 0x59, 0x73, 0x7d, 0x6f, 0x61,
+       0xad, 0xa3, 0xb1, 0xbf, 0x95, 0x9b, 0x89, 0x87,
+       0xdd, 0xd3, 0xc1, 0xcf, 0xe5, 0xeb, 0xf9, 0xf7,
+       0x4d, 0x43, 0x51, 0x5f, 0x75, 0x7b, 0x69, 0x67,
+       0x3d, 0x33, 0x21, 0x2f, 0x05, 0x0b, 0x19, 0x17,
+       0x76, 0x78, 0x6a, 0x64, 0x4e, 0x40, 0x52, 0x5c,
+       0x06, 0x08, 0x1a, 0x14, 0x3e, 0x30, 0x22, 0x2c,
+       0x96, 0x98, 0x8a, 0x84, 0xae, 0xa0, 0xb2, 0xbc,
+       0xe6, 0xe8, 0xfa, 0xf4, 0xde, 0xd0, 0xc2, 0xcc,
+       0x41, 0x4f, 0x5d, 0x53, 0x79, 0x77, 0x65, 0x6b,
+       0x31, 0x3f, 0x2d, 0x23, 0x09, 0x07, 0x15, 0x1b,
+       0xa1, 0xaf, 0xbd, 0xb3, 0x99, 0x97, 0x85, 0x8b,
+       0xd1, 0xdf, 0xcd, 0xc3, 0xe9, 0xe7, 0xf5, 0xfb,
+       0x9a, 0x94, 0x86, 0x88, 0xa2, 0xac, 0xbe, 0xb0,
+       0xea, 0xe4, 0xf6, 0xf8, 0xd2, 0xdc, 0xce, 0xc0,
+       0x7a, 0x74, 0x66, 0x68, 0x42, 0x4c, 0x5e, 0x50,
+       0x0a, 0x04, 0x16, 0x18, 0x32, 0x3c, 0x2e, 0x20,
+       0xec, 0xe2, 0xf0, 0xfe, 0xd4, 0xda, 0xc8, 0xc6,
+       0x9c, 0x92, 0x80, 0x8e, 0xa4, 0xaa, 0xb8, 0xb6,
+       0x0c, 0x02, 0x10, 0x1e, 0x34, 0x3a, 0x28, 0x26,
+       0x7c, 0x72, 0x60, 0x6e, 0x44, 0x4a, 0x58, 0x56,
+       0x37, 0x39, 0x2b, 0x25, 0x0f, 0x01, 0x13, 0x1d,
+       0x47, 0x49, 0x5b, 0x55, 0x7f, 0x71, 0x63, 0x6d,
+       0xd7, 0xd9, 0xcb, 0xc5, 0xef, 0xe1, 0xf3, 0xfd,
+       0xa7, 0xa9, 0xbb, 0xb5, 0x9f, 0x91, 0x83, 0x8d
+};
+
+/*
+ * Exchanges columns in each of 4 rows
+ * row0 - unchanged, row1- shifted left 1,
+ * row2 - shifted left 2 and row3 - shifted left 3
+ */
+static void shift_rows(u8 *state)
+{
+       u8 tmp;
+
+       /* just substitute row 0 */
+       state[0] = sbox[state[0]];
+       state[4] = sbox[state[4]];
+       state[8] = sbox[state[8]];
+       state[12] = sbox[state[12]];
+
+       /* rotate row 1 */
+       tmp = sbox[state[1]];
+       state[1] = sbox[state[5]];
+       state[5] = sbox[state[9]];
+       state[9] = sbox[state[13]];
+       state[13] = tmp;
+
+       /* rotate row 2 */
+       tmp = sbox[state[2]];
+       state[2] = sbox[state[10]];
+       state[10] = tmp;
+       tmp = sbox[state[6]];
+       state[6] = sbox[state[14]];
+       state[14] = tmp;
+
+       /* rotate row 3 */
+       tmp = sbox[state[15]];
+       state[15] = sbox[state[11]];
+       state[11] = sbox[state[7]];
+       state[7] = sbox[state[3]];
+       state[3] = tmp;
+}
+
+/*
+ * restores columns in each of 4 rows
+ * row0 - unchanged, row1- shifted right 1,
+ * row2 - shifted right 2 and row3 - shifted right 3
+ */
+static void inv_shift_rows(u8 *state)
+{
+       u8 tmp;
+
+       /* restore row 0 */
+       state[0] = inv_sbox[state[0]];
+       state[4] = inv_sbox[state[4]];
+       state[8] = inv_sbox[state[8]];
+       state[12] = inv_sbox[state[12]];
+
+       /* restore row 1 */
+       tmp = inv_sbox[state[13]];
+       state[13] = inv_sbox[state[9]];
+       state[9] = inv_sbox[state[5]];
+       state[5] = inv_sbox[state[1]];
+       state[1] = tmp;
+
+       /* restore row 2 */
+       tmp = inv_sbox[state[2]];
+       state[2] = inv_sbox[state[10]];
+       state[10] = tmp;
+       tmp = inv_sbox[state[6]];
+       state[6] = inv_sbox[state[14]];
+       state[14] = tmp;
+
+       /* restore row 3 */
+       tmp = inv_sbox[state[3]];
+       state[3] = inv_sbox[state[7]];
+       state[7] = inv_sbox[state[11]];
+       state[11] = inv_sbox[state[15]];
+       state[15] = tmp;
+}
+
+/* recombine and mix each row in a column */
+static void mix_sub_columns(u8 *state)
+{
+       u8 tmp[4 * AES_STATECOLS];
+
+       /* mixing column 0 */
+       tmp[0] = x2_sbox[state[0]] ^ x3_sbox[state[5]] ^
+                sbox[state[10]] ^ sbox[state[15]];
+       tmp[1] = sbox[state[0]] ^ x2_sbox[state[5]] ^
+                x3_sbox[state[10]] ^ sbox[state[15]];
+       tmp[2] = sbox[state[0]] ^ sbox[state[5]] ^
+                x2_sbox[state[10]] ^ x3_sbox[state[15]];
+       tmp[3] = x3_sbox[state[0]] ^ sbox[state[5]] ^
+                sbox[state[10]] ^ x2_sbox[state[15]];
+
+       /* mixing column 1 */
+       tmp[4] = x2_sbox[state[4]] ^ x3_sbox[state[9]] ^
+                sbox[state[14]] ^ sbox[state[3]];
+       tmp[5] = sbox[state[4]] ^ x2_sbox[state[9]] ^
+                x3_sbox[state[14]] ^ sbox[state[3]];
+       tmp[6] = sbox[state[4]] ^ sbox[state[9]] ^
+                x2_sbox[state[14]] ^ x3_sbox[state[3]];
+       tmp[7] = x3_sbox[state[4]] ^ sbox[state[9]] ^
+                sbox[state[14]] ^ x2_sbox[state[3]];
+
+       /* mixing column 2 */
+       tmp[8] = x2_sbox[state[8]] ^ x3_sbox[state[13]] ^
+                sbox[state[2]] ^ sbox[state[7]];
+       tmp[9] = sbox[state[8]] ^ x2_sbox[state[13]] ^
+                x3_sbox[state[2]] ^ sbox[state[7]];
+       tmp[10] = sbox[state[8]] ^ sbox[state[13]] ^
+                 x2_sbox[state[2]] ^ x3_sbox[state[7]];
+       tmp[11] = x3_sbox[state[8]] ^ sbox[state[13]] ^
+                 sbox[state[2]] ^ x2_sbox[state[7]];
+
+       /* mixing column 3 */
+       tmp[12] = x2_sbox[state[12]] ^ x3_sbox[state[1]] ^
+                 sbox[state[6]] ^ sbox[state[11]];
+       tmp[13] = sbox[state[12]] ^ x2_sbox[state[1]] ^
+                 x3_sbox[state[6]] ^ sbox[state[11]];
+       tmp[14] = sbox[state[12]] ^ sbox[state[1]] ^
+                 x2_sbox[state[6]] ^ x3_sbox[state[11]];
+       tmp[15] = x3_sbox[state[12]] ^ sbox[state[1]] ^
+                 sbox[state[6]] ^ x2_sbox[state[11]];
+
+       memcpy(state, tmp, sizeof(tmp));
+}
+
+/* restore and un-mix each row in a column */
+static void inv_mix_sub_columns(u8 *state)
+{
+       u8 tmp[4 * AES_STATECOLS];
+       int  i;
+
+       /* restore column 0 */
+       tmp[0] = x_time_e[state[0]] ^ x_time_b[state[1]] ^
+                x_time_d[state[2]] ^ x_time_9[state[3]];
+       tmp[5] = x_time_9[state[0]] ^ x_time_e[state[1]] ^
+                x_time_b[state[2]] ^ x_time_d[state[3]];
+       tmp[10] = x_time_d[state[0]] ^ x_time_9[state[1]] ^
+                 x_time_e[state[2]] ^ x_time_b[state[3]];
+       tmp[15] = x_time_b[state[0]] ^ x_time_d[state[1]] ^
+                 x_time_9[state[2]] ^ x_time_e[state[3]];
+
+       /* restore column 1 */
+       tmp[4] = x_time_e[state[4]] ^ x_time_b[state[5]] ^
+                x_time_d[state[6]] ^ x_time_9[state[7]];
+       tmp[9] = x_time_9[state[4]] ^ x_time_e[state[5]] ^
+                x_time_b[state[6]] ^ x_time_d[state[7]];
+       tmp[14] = x_time_d[state[4]] ^ x_time_9[state[5]] ^
+                 x_time_e[state[6]] ^ x_time_b[state[7]];
+       tmp[3] = x_time_b[state[4]] ^ x_time_d[state[5]] ^
+                x_time_9[state[6]] ^ x_time_e[state[7]];
+
+       /* restore column 2 */
+       tmp[8] = x_time_e[state[8]] ^ x_time_b[state[9]] ^
+                x_time_d[state[10]] ^ x_time_9[state[11]];
+       tmp[13] = x_time_9[state[8]] ^ x_time_e[state[9]] ^
+                 x_time_b[state[10]] ^ x_time_d[state[11]];
+       tmp[2] = x_time_d[state[8]] ^ x_time_9[state[9]] ^
+                x_time_e[state[10]] ^ x_time_b[state[11]];
+       tmp[7] = x_time_b[state[8]] ^ x_time_d[state[9]] ^
+                x_time_9[state[10]] ^ x_time_e[state[11]];
+
+       /* restore column 3 */
+       tmp[12] = x_time_e[state[12]] ^ x_time_b[state[13]] ^
+                 x_time_d[state[14]] ^ x_time_9[state[15]];
+       tmp[1] = x_time_9[state[12]] ^ x_time_e[state[13]] ^
+                x_time_b[state[14]] ^ x_time_d[state[15]];
+       tmp[6] = x_time_d[state[12]] ^ x_time_9[state[13]] ^
+                x_time_e[state[14]] ^ x_time_b[state[15]];
+       tmp[11] = x_time_b[state[12]] ^ x_time_d[state[13]] ^
+                 x_time_9[state[14]] ^ x_time_e[state[15]];
+
+       for (i = 0; i < 4 * AES_STATECOLS; i++)
+               state[i] = inv_sbox[tmp[i]];
+}
+
+/*
+ * encrypt/decrypt columns of the key
+ * n.b. you can replace this with byte-wise xor if you wish.
+ */
+static void add_round_key(u32 *state, u32 *key)
+{
+       int idx;
+
+       for (idx = 0; idx < 4; idx++)
+               state[idx] ^= key[idx];
+}
+
+static u8 rcon[11] = {
+       0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36
+};
+
+/* produce AES_STATECOLS bytes for each round */
+void aes_expand_key(u8 *key, u8 *expkey)
+{
+       u8 tmp0, tmp1, tmp2, tmp3, tmp4;
+       u32 idx;
+
+       memcpy(expkey, key, AES_KEYCOLS * 4);
+
+       for (idx = AES_KEYCOLS; idx < AES_STATECOLS * (AES_ROUNDS + 1); idx++) {
+               tmp0 = expkey[4*idx - 4];
+               tmp1 = expkey[4*idx - 3];
+               tmp2 = expkey[4*idx - 2];
+               tmp3 = expkey[4*idx - 1];
+               if (!(idx % AES_KEYCOLS)) {
+                       tmp4 = tmp3;
+                       tmp3 = sbox[tmp0];
+                       tmp0 = sbox[tmp1] ^ rcon[idx / AES_KEYCOLS];
+                       tmp1 = sbox[tmp2];
+                       tmp2 = sbox[tmp4];
+               } else if ((AES_KEYCOLS > 6) && (idx % AES_KEYCOLS == 4)) {
+                       tmp0 = sbox[tmp0];
+                       tmp1 = sbox[tmp1];
+                       tmp2 = sbox[tmp2];
+                       tmp3 = sbox[tmp3];
+               }
+
+               expkey[4*idx+0] = expkey[4*idx - 4*AES_KEYCOLS + 0] ^ tmp0;
+               expkey[4*idx+1] = expkey[4*idx - 4*AES_KEYCOLS + 1] ^ tmp1;
+               expkey[4*idx+2] = expkey[4*idx - 4*AES_KEYCOLS + 2] ^ tmp2;
+               expkey[4*idx+3] = expkey[4*idx - 4*AES_KEYCOLS + 3] ^ tmp3;
+       }
+}
+
+/* encrypt one 128 bit block */
+void aes_encrypt(u8 *in, u8 *expkey, u8 *out)
+{
+       u8 state[AES_STATECOLS * 4];
+       u32 round;
+
+       memcpy(state, in, AES_STATECOLS * 4);
+       add_round_key((u32 *)state, (u32 *)expkey);
+
+       for (round = 1; round < AES_ROUNDS + 1; round++) {
+               if (round < AES_ROUNDS)
+                       mix_sub_columns(state);
+               else
+                       shift_rows(state);
+
+               add_round_key((u32 *)state,
+                             (u32 *)expkey + round * AES_STATECOLS);
+       }
+
+       memcpy(out, state, sizeof(state));
+}
+
+void aes_decrypt(u8 *in, u8 *expkey, u8 *out)
+{
+       u8 state[AES_STATECOLS * 4];
+       int round;
+
+       memcpy(state, in, sizeof(state));
+
+       add_round_key((u32 *)state,
+                     (u32 *)expkey + AES_ROUNDS * AES_STATECOLS);
+       inv_shift_rows(state);
+
+       for (round = AES_ROUNDS; round--; ) {
+               add_round_key((u32 *)state,
+                             (u32 *)expkey + round * AES_STATECOLS);
+               if (round)
+                       inv_mix_sub_columns(state);
+       }
+
+       memcpy(out, state, sizeof(state));
+}