572 lines
13 KiB
C
572 lines
13 KiB
C
/*
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* FIPS-197 compliant AES implementation
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*
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* Copyright (C) 2006-2007 Christophe Devine
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* * Redistributions of source code _must_ retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form may or may not reproduce the above
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* copyright notice, this list of conditions and the following
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* disclaimer in the documentation and/or other materials provided
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* with the distribution.
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* * Neither the name of XySSL nor the names of its contributors may be
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* used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
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* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
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* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
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* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
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* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
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* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* The AES block cipher was designed by Vincent Rijmen and Joan Daemen.
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*
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* http://csrc.nist.gov/encryption/aes/rijndael/Rijndael.pdf
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* http://csrc.nist.gov/publications/fips/fips197/fips-197.pdf
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*/
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#include "mupdf/fitz.h"
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#include <string.h>
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#define aes_context fz_aes
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/* AES block cipher implementation from XYSSL */
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/*
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* 32-bit integer manipulation macros (little endian)
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*/
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#ifndef GET_ULONG_LE
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#define GET_ULONG_LE(n,b,i) \
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{ \
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(n) = ( (unsigned long) (b)[(i)] ) \
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| ( (unsigned long) (b)[(i) + 1] << 8 ) \
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| ( (unsigned long) (b)[(i) + 2] << 16 ) \
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| ( (unsigned long) (b)[(i) + 3] << 24 ); \
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}
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#endif
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#ifndef PUT_ULONG_LE
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#define PUT_ULONG_LE(n,b,i) \
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{ \
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(b)[(i) ] = (unsigned char) ( (n) ); \
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(b)[(i) + 1] = (unsigned char) ( (n) >> 8 ); \
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(b)[(i) + 2] = (unsigned char) ( (n) >> 16 ); \
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(b)[(i) + 3] = (unsigned char) ( (n) >> 24 ); \
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}
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#endif
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/*
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* Forward S-box & tables
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*/
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static unsigned char FSb[256];
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static unsigned long FT0[256];
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static unsigned long FT1[256];
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static unsigned long FT2[256];
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static unsigned long FT3[256];
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/*
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* Reverse S-box & tables
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*/
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static unsigned char RSb[256];
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static unsigned long RT0[256];
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static unsigned long RT1[256];
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static unsigned long RT2[256];
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static unsigned long RT3[256];
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/*
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* Round constants
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*/
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static unsigned long RCON[10];
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/*
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* Tables generation code
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*/
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#define ROTL8(x) ( ( x << 8 ) & 0xFFFFFFFF ) | ( x >> 24 )
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#define XTIME(x) ( ( x << 1 ) ^ ( ( x & 0x80 ) ? 0x1B : 0x00 ) )
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#define MUL(x,y) ( ( x && y ) ? pow[(log[x]+log[y]) % 255] : 0 )
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static int aes_init_done = 0;
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static void aes_gen_tables( void )
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{
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int i, x, y, z;
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int pow[256];
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int log[256];
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/*
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* compute pow and log tables over GF(2^8)
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*/
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for( i = 0, x = 1; i < 256; i++ )
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{
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pow[i] = x;
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log[x] = i;
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x = ( x ^ XTIME( x ) ) & 0xFF;
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}
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/*
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* calculate the round constants
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*/
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for( i = 0, x = 1; i < 10; i++ )
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{
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RCON[i] = (unsigned long) x;
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x = XTIME( x ) & 0xFF;
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}
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/*
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* generate the forward and reverse S-boxes
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*/
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FSb[0x00] = 0x63;
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RSb[0x63] = 0x00;
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for( i = 1; i < 256; i++ )
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{
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x = pow[255 - log[i]];
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y = x; y = ( (y << 1) | (y >> 7) ) & 0xFF;
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x ^= y; y = ( (y << 1) | (y >> 7) ) & 0xFF;
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x ^= y; y = ( (y << 1) | (y >> 7) ) & 0xFF;
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x ^= y; y = ( (y << 1) | (y >> 7) ) & 0xFF;
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x ^= y ^ 0x63;
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FSb[i] = (unsigned char) x;
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RSb[x] = (unsigned char) i;
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}
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/*
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* generate the forward and reverse tables
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*/
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for( i = 0; i < 256; i++ )
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{
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x = FSb[i];
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y = XTIME( x ) & 0xFF;
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z = ( y ^ x ) & 0xFF;
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FT0[i] = ( (unsigned long) y ) ^
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( (unsigned long) x << 8 ) ^
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( (unsigned long) x << 16 ) ^
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( (unsigned long) z << 24 );
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FT1[i] = ROTL8( FT0[i] );
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FT2[i] = ROTL8( FT1[i] );
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FT3[i] = ROTL8( FT2[i] );
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x = RSb[i];
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RT0[i] = ( (unsigned long) MUL( 0x0E, x ) ) ^
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( (unsigned long) MUL( 0x09, x ) << 8 ) ^
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( (unsigned long) MUL( 0x0D, x ) << 16 ) ^
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( (unsigned long) MUL( 0x0B, x ) << 24 );
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RT1[i] = ROTL8( RT0[i] );
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RT2[i] = ROTL8( RT1[i] );
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RT3[i] = ROTL8( RT2[i] );
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}
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}
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/*
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* AES key schedule (encryption)
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*/
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int fz_aes_setkey_enc( aes_context *ctx, const unsigned char *key, int keysize )
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{
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int i;
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unsigned long *RK;
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#if !defined(XYSSL_AES_ROM_TABLES)
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if( aes_init_done == 0 )
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{
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aes_gen_tables();
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aes_init_done = 1;
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}
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#endif
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switch( keysize )
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{
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case 128: ctx->nr = 10; break;
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case 192: ctx->nr = 12; break;
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case 256: ctx->nr = 14; break;
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default : return 1;
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}
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#if defined(PADLOCK_ALIGN16)
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ctx->rk = RK = PADLOCK_ALIGN16( ctx->buf );
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#else
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ctx->rk = RK = ctx->buf;
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#endif
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for( i = 0; i < (keysize >> 5); i++ )
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{
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GET_ULONG_LE( RK[i], key, i << 2 );
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}
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switch( ctx->nr )
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{
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case 10:
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for( i = 0; i < 10; i++, RK += 4 )
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{
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RK[4] = RK[0] ^ RCON[i] ^
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( FSb[ ( RK[3] >> 8 ) & 0xFF ] ) ^
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( FSb[ ( RK[3] >> 16 ) & 0xFF ] << 8 ) ^
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( FSb[ ( RK[3] >> 24 ) & 0xFF ] << 16 ) ^
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( FSb[ ( RK[3] ) & 0xFF ] << 24 );
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RK[5] = RK[1] ^ RK[4];
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RK[6] = RK[2] ^ RK[5];
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RK[7] = RK[3] ^ RK[6];
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}
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break;
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case 12:
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for( i = 0; i < 8; i++, RK += 6 )
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{
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RK[6] = RK[0] ^ RCON[i] ^
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( FSb[ ( RK[5] >> 8 ) & 0xFF ] ) ^
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( FSb[ ( RK[5] >> 16 ) & 0xFF ] << 8 ) ^
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( FSb[ ( RK[5] >> 24 ) & 0xFF ] << 16 ) ^
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( FSb[ ( RK[5] ) & 0xFF ] << 24 );
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RK[7] = RK[1] ^ RK[6];
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RK[8] = RK[2] ^ RK[7];
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RK[9] = RK[3] ^ RK[8];
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RK[10] = RK[4] ^ RK[9];
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RK[11] = RK[5] ^ RK[10];
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}
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break;
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case 14:
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for( i = 0; i < 7; i++, RK += 8 )
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{
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RK[8] = RK[0] ^ RCON[i] ^
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( FSb[ ( RK[7] >> 8 ) & 0xFF ] ) ^
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( FSb[ ( RK[7] >> 16 ) & 0xFF ] << 8 ) ^
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( FSb[ ( RK[7] >> 24 ) & 0xFF ] << 16 ) ^
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( FSb[ ( RK[7] ) & 0xFF ] << 24 );
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RK[9] = RK[1] ^ RK[8];
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RK[10] = RK[2] ^ RK[9];
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RK[11] = RK[3] ^ RK[10];
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RK[12] = RK[4] ^
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( FSb[ ( RK[11] ) & 0xFF ] ) ^
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( FSb[ ( RK[11] >> 8 ) & 0xFF ] << 8 ) ^
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( FSb[ ( RK[11] >> 16 ) & 0xFF ] << 16 ) ^
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( FSb[ ( RK[11] >> 24 ) & 0xFF ] << 24 );
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RK[13] = RK[5] ^ RK[12];
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RK[14] = RK[6] ^ RK[13];
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RK[15] = RK[7] ^ RK[14];
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}
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break;
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default:
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break;
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}
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return 0;
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}
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/*
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* AES key schedule (decryption)
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*/
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int fz_aes_setkey_dec(aes_context *ctx, const unsigned char *key, int keysize)
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{
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int i, j;
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aes_context cty;
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unsigned long *RK;
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unsigned long *SK;
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switch( keysize )
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{
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case 128: ctx->nr = 10; break;
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case 192: ctx->nr = 12; break;
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case 256: ctx->nr = 14; break;
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default: return 1;
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}
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#if defined(PADLOCK_ALIGN16)
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ctx->rk = RK = PADLOCK_ALIGN16( ctx->buf );
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#else
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ctx->rk = RK = ctx->buf;
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#endif
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i = fz_aes_setkey_enc( &cty, key, keysize );
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if (i)
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return i;
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SK = cty.rk + cty.nr * 4;
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*RK++ = *SK++;
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*RK++ = *SK++;
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*RK++ = *SK++;
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*RK++ = *SK++;
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for( i = ctx->nr - 1, SK -= 8; i > 0; i--, SK -= 8 )
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{
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for( j = 0; j < 4; j++, SK++ )
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{
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*RK++ = RT0[ FSb[ ( *SK ) & 0xFF ] ] ^
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RT1[ FSb[ ( *SK >> 8 ) & 0xFF ] ] ^
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RT2[ FSb[ ( *SK >> 16 ) & 0xFF ] ] ^
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RT3[ FSb[ ( *SK >> 24 ) & 0xFF ] ];
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}
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}
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*RK++ = *SK++;
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*RK++ = *SK++;
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*RK++ = *SK++;
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*RK = *SK;
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memset( &cty, 0, sizeof( aes_context ) );
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return 0;
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}
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#define AES_FROUND(X0,X1,X2,X3,Y0,Y1,Y2,Y3) \
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{ \
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X0 = *RK++ ^ FT0[ ( Y0 ) & 0xFF ] ^ \
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FT1[ ( Y1 >> 8 ) & 0xFF ] ^ \
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FT2[ ( Y2 >> 16 ) & 0xFF ] ^ \
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FT3[ ( Y3 >> 24 ) & 0xFF ]; \
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\
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X1 = *RK++ ^ FT0[ ( Y1 ) & 0xFF ] ^ \
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FT1[ ( Y2 >> 8 ) & 0xFF ] ^ \
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FT2[ ( Y3 >> 16 ) & 0xFF ] ^ \
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FT3[ ( Y0 >> 24 ) & 0xFF ]; \
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\
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X2 = *RK++ ^ FT0[ ( Y2 ) & 0xFF ] ^ \
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FT1[ ( Y3 >> 8 ) & 0xFF ] ^ \
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FT2[ ( Y0 >> 16 ) & 0xFF ] ^ \
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FT3[ ( Y1 >> 24 ) & 0xFF ]; \
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\
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X3 = *RK++ ^ FT0[ ( Y3 ) & 0xFF ] ^ \
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FT1[ ( Y0 >> 8 ) & 0xFF ] ^ \
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FT2[ ( Y1 >> 16 ) & 0xFF ] ^ \
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FT3[ ( Y2 >> 24 ) & 0xFF ]; \
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}
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#define AES_RROUND(X0,X1,X2,X3,Y0,Y1,Y2,Y3) \
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{ \
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X0 = *RK++ ^ RT0[ ( Y0 ) & 0xFF ] ^ \
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RT1[ ( Y3 >> 8 ) & 0xFF ] ^ \
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RT2[ ( Y2 >> 16 ) & 0xFF ] ^ \
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RT3[ ( Y1 >> 24 ) & 0xFF ]; \
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\
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X1 = *RK++ ^ RT0[ ( Y1 ) & 0xFF ] ^ \
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RT1[ ( Y0 >> 8 ) & 0xFF ] ^ \
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RT2[ ( Y3 >> 16 ) & 0xFF ] ^ \
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RT3[ ( Y2 >> 24 ) & 0xFF ]; \
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\
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X2 = *RK++ ^ RT0[ ( Y2 ) & 0xFF ] ^ \
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RT1[ ( Y1 >> 8 ) & 0xFF ] ^ \
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RT2[ ( Y0 >> 16 ) & 0xFF ] ^ \
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RT3[ ( Y3 >> 24 ) & 0xFF ]; \
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\
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X3 = *RK++ ^ RT0[ ( Y3 ) & 0xFF ] ^ \
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RT1[ ( Y2 >> 8 ) & 0xFF ] ^ \
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RT2[ ( Y1 >> 16 ) & 0xFF ] ^ \
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RT3[ ( Y0 >> 24 ) & 0xFF ]; \
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}
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/*
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* AES-ECB block encryption/decryption
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*/
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void fz_aes_crypt_ecb( aes_context *ctx,
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int mode,
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const unsigned char input[16],
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unsigned char output[16] )
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{
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int i;
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unsigned long *RK, X0, X1, X2, X3, Y0, Y1, Y2, Y3;
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#if defined(XYSSL_PADLOCK_C) && defined(XYSSL_HAVE_X86)
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if( padlock_supports( PADLOCK_ACE ) )
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{
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if( padlock_xcryptecb( ctx, mode, input, output ) == 0 )
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return;
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}
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#endif
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RK = ctx->rk;
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GET_ULONG_LE( X0, input, 0 ); X0 ^= *RK++;
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GET_ULONG_LE( X1, input, 4 ); X1 ^= *RK++;
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GET_ULONG_LE( X2, input, 8 ); X2 ^= *RK++;
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GET_ULONG_LE( X3, input, 12 ); X3 ^= *RK++;
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if( mode == FZ_AES_DECRYPT )
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{
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for( i = (ctx->nr >> 1) - 1; i > 0; i-- )
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{
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AES_RROUND( Y0, Y1, Y2, Y3, X0, X1, X2, X3 );
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AES_RROUND( X0, X1, X2, X3, Y0, Y1, Y2, Y3 );
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}
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AES_RROUND( Y0, Y1, Y2, Y3, X0, X1, X2, X3 );
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X0 = *RK++ ^ ( RSb[ ( Y0 ) & 0xFF ] ) ^
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( RSb[ ( Y3 >> 8 ) & 0xFF ] << 8 ) ^
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( RSb[ ( Y2 >> 16 ) & 0xFF ] << 16 ) ^
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( RSb[ ( Y1 >> 24 ) & 0xFF ] << 24 );
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X1 = *RK++ ^ ( RSb[ ( Y1 ) & 0xFF ] ) ^
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( RSb[ ( Y0 >>8 ) & 0xFF ] << 8 ) ^
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( RSb[ ( Y3 >> 16 ) & 0xFF ] << 16 ) ^
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( RSb[ ( Y2 >> 24 ) & 0xFF ] << 24 );
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X2 = *RK++ ^ ( RSb[ ( Y2 ) & 0xFF ] ) ^
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( RSb[ ( Y1 >> 8 ) & 0xFF ] << 8 ) ^
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( RSb[ ( Y0 >> 16 ) & 0xFF ] << 16 ) ^
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( RSb[ ( Y3 >> 24 ) & 0xFF ] << 24 );
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X3 = *RK ^ ( RSb[ ( Y3 ) & 0xFF ] ) ^
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( RSb[ ( Y2 >> 8 ) & 0xFF ] << 8 ) ^
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( RSb[ ( Y1 >> 16 ) & 0xFF ] << 16 ) ^
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( RSb[ ( Y0 >> 24 ) & 0xFF ] << 24 );
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}
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else /* FZ_AES_ENCRYPT */
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{
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for( i = (ctx->nr >> 1) - 1; i > 0; i-- )
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{
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AES_FROUND( Y0, Y1, Y2, Y3, X0, X1, X2, X3 );
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AES_FROUND( X0, X1, X2, X3, Y0, Y1, Y2, Y3 );
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}
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AES_FROUND( Y0, Y1, Y2, Y3, X0, X1, X2, X3 );
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X0 = *RK++ ^ ( FSb[ ( Y0 ) & 0xFF ] ) ^
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( FSb[ ( Y1 >> 8 ) & 0xFF ] << 8 ) ^
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( FSb[ ( Y2 >> 16 ) & 0xFF ] << 16 ) ^
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( FSb[ ( Y3 >> 24 ) & 0xFF ] << 24 );
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X1 = *RK++ ^ ( FSb[ ( Y1 ) & 0xFF ] ) ^
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( FSb[ ( Y2 >> 8 ) & 0xFF ] << 8 ) ^
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( FSb[ ( Y3 >> 16 ) & 0xFF ] << 16 ) ^
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( FSb[ ( Y0 >> 24 ) & 0xFF ] << 24 );
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X2 = *RK++ ^ ( FSb[ ( Y2 ) & 0xFF ] ) ^
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( FSb[ ( Y3 >> 8 ) & 0xFF ] << 8 ) ^
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( FSb[ ( Y0 >> 16 ) & 0xFF ] << 16 ) ^
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( FSb[ ( Y1 >> 24 ) & 0xFF ] << 24 );
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X3 = *RK ^ ( FSb[ ( Y3 ) & 0xFF ] ) ^
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( FSb[ ( Y0 >> 8 ) & 0xFF ] << 8 ) ^
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( FSb[ ( Y1 >> 16 ) & 0xFF ] << 16 ) ^
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( FSb[ ( Y2 >> 24 ) & 0xFF ] << 24 );
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}
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PUT_ULONG_LE( X0, output, 0 );
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PUT_ULONG_LE( X1, output, 4 );
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PUT_ULONG_LE( X2, output, 8 );
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PUT_ULONG_LE( X3, output, 12 );
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}
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/*
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* AES-CBC buffer encryption/decryption
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*/
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void fz_aes_crypt_cbc( aes_context *ctx,
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int mode,
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size_t length,
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unsigned char iv[16],
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const unsigned char *input,
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unsigned char *output )
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{
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int i;
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unsigned char temp[16];
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|
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#if defined(XYSSL_PADLOCK_C) && defined(XYSSL_HAVE_X86)
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if( padlock_supports( PADLOCK_ACE ) )
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{
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if( padlock_xcryptcbc( ctx, mode, length, iv, input, output ) == 0 )
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return;
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}
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#endif
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|
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if( mode == FZ_AES_DECRYPT )
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{
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while( length > 0 )
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{
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memcpy( temp, input, 16 );
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fz_aes_crypt_ecb( ctx, mode, input, output );
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|
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for( i = 0; i < 16; i++ )
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output[i] = (unsigned char)( output[i] ^ iv[i] );
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memcpy( iv, temp, 16 );
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|
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input += 16;
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output += 16;
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length -= 16;
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}
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}
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else
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{
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while( length > 0 )
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{
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for( i = 0; i < 16; i++ )
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output[i] = (unsigned char)( input[i] ^ iv[i] );
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|
|
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fz_aes_crypt_ecb( ctx, mode, output, output );
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memcpy( iv, output, 16 );
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|
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input += 16;
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output += 16;
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length -= 16;
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}
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}
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}
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|
|
|
/*
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* AES-CFB buffer encryption/decryption
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|
*/
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|
void fz_aes_crypt_cfb( aes_context *ctx,
|
|
int mode,
|
|
int length,
|
|
int *iv_off,
|
|
unsigned char iv[16],
|
|
const unsigned char *input,
|
|
unsigned char *output )
|
|
{
|
|
int c, n = *iv_off;
|
|
|
|
if( mode == FZ_AES_DECRYPT )
|
|
{
|
|
while( length-- )
|
|
{
|
|
if( n == 0 )
|
|
fz_aes_crypt_ecb( ctx, FZ_AES_ENCRYPT, iv, iv );
|
|
|
|
c = *input++;
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|
*output++ = (unsigned char)( c ^ iv[n] );
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|
iv[n] = (unsigned char) c;
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|
|
|
n = (n + 1) & 0x0F;
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|
}
|
|
}
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|
else
|
|
{
|
|
while( length-- )
|
|
{
|
|
if( n == 0 )
|
|
fz_aes_crypt_ecb( ctx, FZ_AES_ENCRYPT, iv, iv );
|
|
|
|
iv[n] = *output++ = (unsigned char)( iv[n] ^ *input++ );
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|
|
|
n = (n + 1) & 0x0F;
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|
}
|
|
}
|
|
|
|
*iv_off = n;
|
|
}
|