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+/*
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+ * Copyright(C) 2006 Cameron Rich
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+ *
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+ * This library is free software; you can redistribute it and/or modify
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+ * it under the terms of the GNU Lesser General Public License as published by
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+ * the Free Software Foundation; either version 2 of the License, or
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+ * (at your option) any later version.
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+ *
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+ * This library is distributed in the hope that it will be useful,
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+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
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+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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+ * GNU Lesser General Public License for more details.
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+ *
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+ * You should have received a copy of the GNU Lesser General Public License
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+ * along with this library; if not, write to the Free Software
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+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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+ */
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+
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+/**
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+ * AES implementation - this is a small code version. There are much faster
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+ * versions around but they are much larger in size (i.e. they use large
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+ * submix tables).
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+ */
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+
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+#include <string.h>
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+#include "crypto.h"
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+
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+/* all commented out in skeleton mode */
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+#ifndef CONFIG_SSL_SKELETON_MODE
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+
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+#define rot1(x) (((x) << 24) | ((x) >> 8))
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+#define rot2(x) (((x) << 16) | ((x) >> 16))
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+#define rot3(x) (((x) << 8) | ((x) >> 24))
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+
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+/*
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+ * This cute trick does 4 'mul by two' at once. Stolen from
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+ * Dr B. R. Gladman <brg@gladman.uk.net> but I'm sure the u-(u>>7) is
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+ * a standard graphics trick
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+ * The key to this is that we need to xor with 0x1b if the top bit is set.
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+ * a 1xxx xxxx 0xxx 0xxx First we mask the 7bit,
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+ * b 1000 0000 0000 0000 then we shift right by 7 putting the 7bit in 0bit,
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+ * c 0000 0001 0000 0000 we then subtract (c) from (b)
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+ * d 0111 1111 0000 0000 and now we and with our mask
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+ * e 0001 1011 0000 0000
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+ */
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+#define mt 0x80808080
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+#define ml 0x7f7f7f7f
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+#define mh 0xfefefefe
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+#define mm 0x1b1b1b1b
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+#define mul2(x,t) ((t)=((x)&mt), \
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+ ((((x)+(x))&mh)^(((t)-((t)>>7))&mm)))
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+
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+#define inv_mix_col(x,f2,f4,f8,f9) (\
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+ (f2)=mul2(x,f2), \
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+ (f4)=mul2(f2,f4), \
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+ (f8)=mul2(f4,f8), \
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+ (f9)=(x)^(f8), \
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+ (f8)=((f2)^(f4)^(f8)), \
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+ (f2)^=(f9), \
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+ (f4)^=(f9), \
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+ (f8)^=rot3(f2), \
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+ (f8)^=rot2(f4), \
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+ (f8)^rot1(f9))
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+
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+/* some macros to do endian independent byte extraction */
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+#define n2l(c,l) l=ntohl(*c); c++
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+#define l2n(l,c) *c++=htonl(l)
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+
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+/*
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+ * AES S-box
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+ */
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+static const uint8_t aes_sbox[256] =
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+{
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+ 0x63,0x7C,0x77,0x7B,0xF2,0x6B,0x6F,0xC5,
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+ 0x30,0x01,0x67,0x2B,0xFE,0xD7,0xAB,0x76,
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+ 0xCA,0x82,0xC9,0x7D,0xFA,0x59,0x47,0xF0,
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+ 0xAD,0xD4,0xA2,0xAF,0x9C,0xA4,0x72,0xC0,
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+ 0xB7,0xFD,0x93,0x26,0x36,0x3F,0xF7,0xCC,
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+ 0x34,0xA5,0xE5,0xF1,0x71,0xD8,0x31,0x15,
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+ 0x04,0xC7,0x23,0xC3,0x18,0x96,0x05,0x9A,
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+ 0x07,0x12,0x80,0xE2,0xEB,0x27,0xB2,0x75,
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+ 0x09,0x83,0x2C,0x1A,0x1B,0x6E,0x5A,0xA0,
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+ 0x52,0x3B,0xD6,0xB3,0x29,0xE3,0x2F,0x84,
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+ 0x53,0xD1,0x00,0xED,0x20,0xFC,0xB1,0x5B,
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+ 0x6A,0xCB,0xBE,0x39,0x4A,0x4C,0x58,0xCF,
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+ 0xD0,0xEF,0xAA,0xFB,0x43,0x4D,0x33,0x85,
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+ 0x45,0xF9,0x02,0x7F,0x50,0x3C,0x9F,0xA8,
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+ 0x51,0xA3,0x40,0x8F,0x92,0x9D,0x38,0xF5,
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+ 0xBC,0xB6,0xDA,0x21,0x10,0xFF,0xF3,0xD2,
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+ 0xCD,0x0C,0x13,0xEC,0x5F,0x97,0x44,0x17,
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+ 0xC4,0xA7,0x7E,0x3D,0x64,0x5D,0x19,0x73,
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+ 0x60,0x81,0x4F,0xDC,0x22,0x2A,0x90,0x88,
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+ 0x46,0xEE,0xB8,0x14,0xDE,0x5E,0x0B,0xDB,
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+ 0xE0,0x32,0x3A,0x0A,0x49,0x06,0x24,0x5C,
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+ 0xC2,0xD3,0xAC,0x62,0x91,0x95,0xE4,0x79,
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+ 0xE7,0xC8,0x37,0x6D,0x8D,0xD5,0x4E,0xA9,
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+ 0x6C,0x56,0xF4,0xEA,0x65,0x7A,0xAE,0x08,
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+ 0xBA,0x78,0x25,0x2E,0x1C,0xA6,0xB4,0xC6,
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+ 0xE8,0xDD,0x74,0x1F,0x4B,0xBD,0x8B,0x8A,
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+ 0x70,0x3E,0xB5,0x66,0x48,0x03,0xF6,0x0E,
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+ 0x61,0x35,0x57,0xB9,0x86,0xC1,0x1D,0x9E,
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+ 0xE1,0xF8,0x98,0x11,0x69,0xD9,0x8E,0x94,
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+ 0x9B,0x1E,0x87,0xE9,0xCE,0x55,0x28,0xDF,
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+ 0x8C,0xA1,0x89,0x0D,0xBF,0xE6,0x42,0x68,
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+ 0x41,0x99,0x2D,0x0F,0xB0,0x54,0xBB,0x16,
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+};
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+
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+/*
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+ * AES is-box
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+ */
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+static const uint8_t aes_isbox[256] =
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+{
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+ 0x52,0x09,0x6a,0xd5,0x30,0x36,0xa5,0x38,
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+ 0xbf,0x40,0xa3,0x9e,0x81,0xf3,0xd7,0xfb,
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+ 0x7c,0xe3,0x39,0x82,0x9b,0x2f,0xff,0x87,
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+ 0x34,0x8e,0x43,0x44,0xc4,0xde,0xe9,0xcb,
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+ 0x54,0x7b,0x94,0x32,0xa6,0xc2,0x23,0x3d,
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+ 0xee,0x4c,0x95,0x0b,0x42,0xfa,0xc3,0x4e,
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+ 0x08,0x2e,0xa1,0x66,0x28,0xd9,0x24,0xb2,
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+ 0x76,0x5b,0xa2,0x49,0x6d,0x8b,0xd1,0x25,
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+ 0x72,0xf8,0xf6,0x64,0x86,0x68,0x98,0x16,
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+ 0xd4,0xa4,0x5c,0xcc,0x5d,0x65,0xb6,0x92,
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+ 0x6c,0x70,0x48,0x50,0xfd,0xed,0xb9,0xda,
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+ 0x5e,0x15,0x46,0x57,0xa7,0x8d,0x9d,0x84,
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+ 0x90,0xd8,0xab,0x00,0x8c,0xbc,0xd3,0x0a,
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+ 0xf7,0xe4,0x58,0x05,0xb8,0xb3,0x45,0x06,
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+ 0xd0,0x2c,0x1e,0x8f,0xca,0x3f,0x0f,0x02,
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+ 0xc1,0xaf,0xbd,0x03,0x01,0x13,0x8a,0x6b,
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+ 0x3a,0x91,0x11,0x41,0x4f,0x67,0xdc,0xea,
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+ 0x97,0xf2,0xcf,0xce,0xf0,0xb4,0xe6,0x73,
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+ 0x96,0xac,0x74,0x22,0xe7,0xad,0x35,0x85,
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+ 0xe2,0xf9,0x37,0xe8,0x1c,0x75,0xdf,0x6e,
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+ 0x47,0xf1,0x1a,0x71,0x1d,0x29,0xc5,0x89,
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+ 0x6f,0xb7,0x62,0x0e,0xaa,0x18,0xbe,0x1b,
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+ 0xfc,0x56,0x3e,0x4b,0xc6,0xd2,0x79,0x20,
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+ 0x9a,0xdb,0xc0,0xfe,0x78,0xcd,0x5a,0xf4,
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+ 0x1f,0xdd,0xa8,0x33,0x88,0x07,0xc7,0x31,
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+ 0xb1,0x12,0x10,0x59,0x27,0x80,0xec,0x5f,
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+ 0x60,0x51,0x7f,0xa9,0x19,0xb5,0x4a,0x0d,
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+ 0x2d,0xe5,0x7a,0x9f,0x93,0xc9,0x9c,0xef,
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+ 0xa0,0xe0,0x3b,0x4d,0xae,0x2a,0xf5,0xb0,
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+ 0xc8,0xeb,0xbb,0x3c,0x83,0x53,0x99,0x61,
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+ 0x17,0x2b,0x04,0x7e,0xba,0x77,0xd6,0x26,
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+ 0xe1,0x69,0x14,0x63,0x55,0x21,0x0c,0x7d
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+};
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+
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+static const unsigned char Rcon[30]=
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+{
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+ 0x01,0x02,0x04,0x08,0x10,0x20,0x40,0x80,
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+ 0x1b,0x36,0x6c,0xd8,0xab,0x4d,0x9a,0x2f,
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+ 0x5e,0xbc,0x63,0xc6,0x97,0x35,0x6a,0xd4,
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+ 0xb3,0x7d,0xfa,0xef,0xc5,0x91,
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+};
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+
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+/* ----- static functions ----- */
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+static void AES_encrypt(const AES_CTX *ctx, uint32_t *data);
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+static void AES_decrypt(const AES_CTX *ctx, uint32_t *data);
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+
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+/* Perform doubling in Galois Field GF(2^8) using the irreducible polynomial
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+ x^8+x^4+x^3+x+1 */
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+static unsigned char AES_xtime(uint32_t x)
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+{
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+ return x = (x&0x80) ? (x<<1)^0x1b : x<<1;
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+}
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+
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+/**
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+ * Set up AES with the key/iv and cipher size.
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+ */
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+void AES_set_key(AES_CTX *ctx, const uint8_t *key,
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+ const uint8_t *iv, AES_MODE mode)
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+{
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+ int i, ii;
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+ uint32_t *W, tmp, tmp2;
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+ const unsigned char *ip;
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+ int words;
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+
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+ switch (mode)
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+ {
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+ case AES_MODE_128:
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+ i = 10;
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+ words = 4;
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+ break;
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+
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+ case AES_MODE_256:
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+ i = 14;
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+ words = 8;
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+ break;
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+
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+ default: /* fail silently */
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+ return;
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+ }
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+
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+ ctx->rounds = i;
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+ ctx->key_size = words;
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+ W = ctx->ks;
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+ for (i = 0; i < words; i+=2)
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+ {
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+ W[i+0]= ((uint32_t)key[ 0]<<24)|
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+ ((uint32_t)key[ 1]<<16)|
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+ ((uint32_t)key[ 2]<< 8)|
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+ ((uint32_t)key[ 3] );
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+ W[i+1]= ((uint32_t)key[ 4]<<24)|
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+ ((uint32_t)key[ 5]<<16)|
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+ ((uint32_t)key[ 6]<< 8)|
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+ ((uint32_t)key[ 7] );
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+ key += 8;
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+ }
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+
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+ ip = Rcon;
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+ ii = 4 * (ctx->rounds+1);
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+ for (i = words; i<ii; i++)
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+ {
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+ tmp = W[i-1];
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+
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+ if ((i % words) == 0)
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+ {
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+ tmp2 =(uint32_t)aes_sbox[(tmp )&0xff]<< 8;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>> 8)&0xff]<<16;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>>16)&0xff]<<24;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>>24) ];
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+ tmp=tmp2^(((unsigned int)*ip)<<24);
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+ ip++;
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+ }
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+
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+ if ((words == 8) && ((i % words) == 4))
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+ {
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+ tmp2 =(uint32_t)aes_sbox[(tmp )&0xff] ;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>> 8)&0xff]<< 8;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>>16)&0xff]<<16;
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+ tmp2|=(uint32_t)aes_sbox[(tmp>>24) ]<<24;
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+ tmp=tmp2;
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+ }
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+
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+ W[i]=W[i-words]^tmp;
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+ }
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+
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+ /* copy the iv across */
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+ memcpy(ctx->iv, iv, 16);
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+}
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+
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+/**
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+ * Change a key for decryption.
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+ */
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+void AES_convert_key(AES_CTX *ctx)
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+{
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+ int i;
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+ uint32_t *k,w,t1,t2,t3,t4;
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+
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+ k = ctx->ks;
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+ k += 4;
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+
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+ for (i=ctx->rounds*4; i>4; i--)
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+ {
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+ w= *k;
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+ w = inv_mix_col(w,t1,t2,t3,t4);
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+ *k++ =w;
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+ }
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+}
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+
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+/**
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261
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+ * Encrypt a byte sequence (with a block size 16) using the AES cipher.
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+ */
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263
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+void AES_cbc_encrypt(AES_CTX *ctx, const uint8_t *msg, uint8_t *out, int length)
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264
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+{
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265
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+ uint32_t tin0, tin1, tin2, tin3;
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+ uint32_t tout0, tout1, tout2, tout3;
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267
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+ uint32_t tin[4];
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+ uint32_t *iv = (uint32_t *)ctx->iv;
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+ uint32_t *msg_32 = (uint32_t *)msg;
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+ uint32_t *out_32 = (uint32_t *)out;
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+
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272
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+ n2l(iv, tout0);
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+ n2l(iv, tout1);
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+ n2l(iv, tout2);
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|
275
|
+ n2l(iv, tout3);
|
|
276
|
+ iv -= 4;
|
|
277
|
+
|
|
278
|
+ for (length -= 16; length >= 0; length -= 16)
|
|
279
|
+ {
|
|
280
|
+ n2l(msg_32, tin0);
|
|
281
|
+ n2l(msg_32, tin1);
|
|
282
|
+ n2l(msg_32, tin2);
|
|
283
|
+ n2l(msg_32, tin3);
|
|
284
|
+ tin[0] = tin0^tout0;
|
|
285
|
+ tin[1] = tin1^tout1;
|
|
286
|
+ tin[2] = tin2^tout2;
|
|
287
|
+ tin[3] = tin3^tout3;
|
|
288
|
+
|
|
289
|
+ AES_encrypt(ctx, tin);
|
|
290
|
+
|
|
291
|
+ tout0 = tin[0];
|
|
292
|
+ l2n(tout0, out_32);
|
|
293
|
+ tout1 = tin[1];
|
|
294
|
+ l2n(tout1, out_32);
|
|
295
|
+ tout2 = tin[2];
|
|
296
|
+ l2n(tout2, out_32);
|
|
297
|
+ tout3 = tin[3];
|
|
298
|
+ l2n(tout3, out_32);
|
|
299
|
+ }
|
|
300
|
+
|
|
301
|
+ l2n(tout0, iv);
|
|
302
|
+ l2n(tout1, iv);
|
|
303
|
+ l2n(tout2, iv);
|
|
304
|
+ l2n(tout3, iv);
|
|
305
|
+}
|
|
306
|
+
|
|
307
|
+/**
|
|
308
|
+ * Decrypt a byte sequence (with a block size 16) using the AES cipher.
|
|
309
|
+ */
|
|
310
|
+void AES_cbc_decrypt(AES_CTX *ctx, const uint8_t *msg, uint8_t *out, int length)
|
|
311
|
+{
|
|
312
|
+ uint32_t tin0, tin1, tin2, tin3;
|
|
313
|
+ uint32_t xor0,xor1,xor2,xor3;
|
|
314
|
+ uint32_t tout0,tout1,tout2,tout3;
|
|
315
|
+ uint32_t data[4];
|
|
316
|
+ uint32_t *iv = (uint32_t *)ctx->iv;
|
|
317
|
+ uint32_t *msg_32 = (uint32_t *)msg;
|
|
318
|
+ uint32_t *out_32 = (uint32_t *)out;
|
|
319
|
+
|
|
320
|
+ n2l(iv ,xor0);
|
|
321
|
+ n2l(iv, xor1);
|
|
322
|
+ n2l(iv, xor2);
|
|
323
|
+ n2l(iv, xor3);
|
|
324
|
+ iv -= 4;
|
|
325
|
+
|
|
326
|
+ for (length-=16; length >= 0; length -= 16)
|
|
327
|
+ {
|
|
328
|
+ n2l(msg_32, tin0);
|
|
329
|
+ n2l(msg_32, tin1);
|
|
330
|
+ n2l(msg_32, tin2);
|
|
331
|
+ n2l(msg_32, tin3);
|
|
332
|
+
|
|
333
|
+ data[0] = tin0;
|
|
334
|
+ data[1] = tin1;
|
|
335
|
+ data[2] = tin2;
|
|
336
|
+ data[3] = tin3;
|
|
337
|
+
|
|
338
|
+ AES_decrypt(ctx, data);
|
|
339
|
+
|
|
340
|
+ tout0 = data[0]^xor0;
|
|
341
|
+ tout1 = data[1]^xor1;
|
|
342
|
+ tout2 = data[2]^xor2;
|
|
343
|
+ tout3 = data[3]^xor3;
|
|
344
|
+
|
|
345
|
+ xor0 = tin0;
|
|
346
|
+ xor1 = tin1;
|
|
347
|
+ xor2 = tin2;
|
|
348
|
+ xor3 = tin3;
|
|
349
|
+
|
|
350
|
+ l2n(tout0, out_32);
|
|
351
|
+ l2n(tout1, out_32);
|
|
352
|
+ l2n(tout2, out_32);
|
|
353
|
+ l2n(tout3, out_32);
|
|
354
|
+ }
|
|
355
|
+
|
|
356
|
+ l2n(xor0, iv);
|
|
357
|
+ l2n(xor1, iv);
|
|
358
|
+ l2n(xor2, iv);
|
|
359
|
+ l2n(xor3, iv);
|
|
360
|
+}
|
|
361
|
+
|
|
362
|
+/**
|
|
363
|
+ * Encrypt a single block (16 bytes) of data
|
|
364
|
+ */
|
|
365
|
+static void AES_encrypt(const AES_CTX *ctx, uint32_t *data)
|
|
366
|
+{
|
|
367
|
+ /* To make this code smaller, generate the sbox entries on the fly.
|
|
368
|
+ * This will have a really heavy effect upon performance.
|
|
369
|
+ */
|
|
370
|
+ uint32_t tmp[4];
|
|
371
|
+ uint32_t tmp1, old_a0, a0, a1, a2, a3, row;
|
|
372
|
+ int curr_rnd;
|
|
373
|
+ int rounds = ctx->rounds;
|
|
374
|
+ const uint32_t *k = ctx->ks;
|
|
375
|
+
|
|
376
|
+ /* Pre-round key addition */
|
|
377
|
+ for (row = 0; row < 4; row++)
|
|
378
|
+ {
|
|
379
|
+ data[row] ^= *(k++);
|
|
380
|
+ }
|
|
381
|
+
|
|
382
|
+ /* Encrypt one block. */
|
|
383
|
+ for (curr_rnd = 0; curr_rnd < rounds; curr_rnd++)
|
|
384
|
+ {
|
|
385
|
+ /* Perform ByteSub and ShiftRow operations together */
|
|
386
|
+ for (row = 0; row < 4; row++)
|
|
387
|
+ {
|
|
388
|
+ a0 = (uint32_t)aes_sbox[(data[row%4]>>24)&0xFF];
|
|
389
|
+ a1 = (uint32_t)aes_sbox[(data[(row+1)%4]>>16)&0xFF];
|
|
390
|
+ a2 = (uint32_t)aes_sbox[(data[(row+2)%4]>>8)&0xFF];
|
|
391
|
+ a3 = (uint32_t)aes_sbox[(data[(row+3)%4])&0xFF];
|
|
392
|
+
|
|
393
|
+ /* Perform MixColumn iff not last round */
|
|
394
|
+ if (curr_rnd < (rounds - 1))
|
|
395
|
+ {
|
|
396
|
+ tmp1 = a0 ^ a1 ^ a2 ^ a3;
|
|
397
|
+ old_a0 = a0;
|
|
398
|
+
|
|
399
|
+ a0 ^= tmp1 ^ AES_xtime(a0 ^ a1);
|
|
400
|
+ a1 ^= tmp1 ^ AES_xtime(a1 ^ a2);
|
|
401
|
+ a2 ^= tmp1 ^ AES_xtime(a2 ^ a3);
|
|
402
|
+ a3 ^= tmp1 ^ AES_xtime(a3 ^ old_a0);
|
|
403
|
+
|
|
404
|
+ }
|
|
405
|
+
|
|
406
|
+ tmp[row] = ((a0 << 24) | (a1 << 16) | (a2 << 8) | a3);
|
|
407
|
+ }
|
|
408
|
+
|
|
409
|
+ /* KeyAddition - note that it is vital that this loop is separate from
|
|
410
|
+ the MixColumn operation, which must be atomic...*/
|
|
411
|
+ for (row = 0; row < 4; row++)
|
|
412
|
+ {
|
|
413
|
+ data[row] = tmp[row] ^ *(k++);
|
|
414
|
+ }
|
|
415
|
+ }
|
|
416
|
+}
|
|
417
|
+
|
|
418
|
+/**
|
|
419
|
+ * Decrypt a single block (16 bytes) of data
|
|
420
|
+ */
|
|
421
|
+static void AES_decrypt(const AES_CTX *ctx, uint32_t *data)
|
|
422
|
+{
|
|
423
|
+ uint32_t tmp[4];
|
|
424
|
+ uint32_t xt0,xt1,xt2,xt3,xt4,xt5,xt6;
|
|
425
|
+ uint32_t a0, a1, a2, a3, row;
|
|
426
|
+ int curr_rnd;
|
|
427
|
+ int rounds = ctx->rounds;
|
|
428
|
+ uint32_t *k = (uint32_t*)ctx->ks + ((rounds+1)*4);
|
|
429
|
+
|
|
430
|
+ /* pre-round key addition */
|
|
431
|
+ for (row=4; row > 0;row--)
|
|
432
|
+ {
|
|
433
|
+ data[row-1] ^= *(--k);
|
|
434
|
+ }
|
|
435
|
+
|
|
436
|
+ /* Decrypt one block */
|
|
437
|
+ for (curr_rnd=0; curr_rnd < rounds; curr_rnd++)
|
|
438
|
+ {
|
|
439
|
+ /* Perform ByteSub and ShiftRow operations together */
|
|
440
|
+ for (row = 4; row > 0; row--)
|
|
441
|
+ {
|
|
442
|
+ a0 = aes_isbox[(data[(row+3)%4]>>24)&0xFF];
|
|
443
|
+ a1 = aes_isbox[(data[(row+2)%4]>>16)&0xFF];
|
|
444
|
+ a2 = aes_isbox[(data[(row+1)%4]>>8)&0xFF];
|
|
445
|
+ a3 = aes_isbox[(data[row%4])&0xFF];
|
|
446
|
+
|
|
447
|
+ /* Perform MixColumn iff not last round */
|
|
448
|
+ if (curr_rnd<(rounds-1))
|
|
449
|
+ {
|
|
450
|
+ /* The MDS cofefficients (0x09, 0x0B, 0x0D, 0x0E)
|
|
451
|
+ are quite large compared to encryption; this
|
|
452
|
+ operation slows decryption down noticeably. */
|
|
453
|
+ xt0 = AES_xtime(a0^a1);
|
|
454
|
+ xt1 = AES_xtime(a1^a2);
|
|
455
|
+ xt2 = AES_xtime(a2^a3);
|
|
456
|
+ xt3 = AES_xtime(a3^a0);
|
|
457
|
+ xt4 = AES_xtime(xt0^xt1);
|
|
458
|
+ xt5 = AES_xtime(xt1^xt2);
|
|
459
|
+ xt6 = AES_xtime(xt4^xt5);
|
|
460
|
+
|
|
461
|
+ xt0 ^= a1^a2^a3^xt4^xt6;
|
|
462
|
+ xt1 ^= a0^a2^a3^xt5^xt6;
|
|
463
|
+ xt2 ^= a0^a1^a3^xt4^xt6;
|
|
464
|
+ xt3 ^= a0^a1^a2^xt5^xt6;
|
|
465
|
+ tmp[row-1] = ((xt0<<24)|(xt1<<16)|(xt2<<8)|xt3);
|
|
466
|
+ }
|
|
467
|
+ else
|
|
468
|
+ tmp[row-1] = ((a0<<24)|(a1<<16)|(a2<<8)|a3);
|
|
469
|
+ }
|
|
470
|
+
|
|
471
|
+ for (row = 4; row > 0; row--)
|
|
472
|
+ {
|
|
473
|
+ data[row-1] = tmp[row-1] ^ *(--k);
|
|
474
|
+ }
|
|
475
|
+ }
|
|
476
|
+}
|
|
477
|
+
|
|
478
|
+#endif
|