mbedtls/library/padlock.c
2010-03-21 17:37:16 +00:00

161 lines
4.5 KiB
C

/*
* VIA PadLock support functions
*
* Copyright (C) 2006-2010, Paul Bakker <polarssl_maintainer at polarssl.org>
* All rights reserved.
*
* 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.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/*
* This implementation is based on the VIA PadLock Programming Guide:
*
* http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
* programming_guide.pdf
*/
#include "polarssl/config.h"
#if defined(POLARSSL_PADLOCK_C)
#include "polarssl/aes.h"
#include "polarssl/padlock.h"
#if defined(POLARSSL_HAVE_X86)
#include <string.h>
/*
* PadLock detection routine
*/
int padlock_supports( int feature )
{
static int flags = -1;
int ebx, edx;
if( flags == -1 )
{
asm( "movl %%ebx, %0 \n" \
"movl $0xC0000000, %%eax \n" \
"cpuid \n" \
"cmpl $0xC0000001, %%eax \n" \
"movl $0, %%edx \n" \
"jb unsupported \n" \
"movl $0xC0000001, %%eax \n" \
"cpuid \n" \
"unsupported: \n" \
"movl %%edx, %1 \n" \
"movl %2, %%ebx \n"
: "=m" (ebx), "=m" (edx)
: "m" (ebx)
: "eax", "ecx", "edx" );
flags = edx;
}
return( flags & feature );
}
/*
* PadLock AES-ECB block en(de)cryption
*/
int padlock_xcryptecb( aes_context *ctx,
int mode,
const unsigned char input[16],
unsigned char output[16] )
{
int ebx;
unsigned long *rk;
unsigned long *blk;
unsigned long *ctrl;
unsigned char buf[256];
rk = ctx->rk;
blk = PADLOCK_ALIGN16( buf );
memcpy( blk, input, 16 );
ctrl = blk + 4;
*ctrl = 0x80 | ctx->nr | ( ( ctx->nr + ( mode^1 ) - 10 ) << 9 );
asm( "pushfl; popfl \n" \
"movl %%ebx, %0 \n" \
"movl $1, %%ecx \n" \
"movl %2, %%edx \n" \
"movl %3, %%ebx \n" \
"movl %4, %%esi \n" \
"movl %4, %%edi \n" \
".byte 0xf3,0x0f,0xa7,0xc8\n" \
"movl %1, %%ebx \n"
: "=m" (ebx)
: "m" (ebx), "m" (ctrl), "m" (rk), "m" (blk)
: "ecx", "edx", "esi", "edi" );
memcpy( output, blk, 16 );
return( 0 );
}
/*
* PadLock AES-CBC buffer en(de)cryption
*/
int padlock_xcryptcbc( aes_context *ctx,
int mode,
int length,
unsigned char iv[16],
const unsigned char *input,
unsigned char *output )
{
int ebx, count;
unsigned long *rk;
unsigned long *iw;
unsigned long *ctrl;
unsigned char buf[256];
if( ( (long) input & 15 ) != 0 ||
( (long) output & 15 ) != 0 )
return( POLARSSL_ERR_PADLOCK_DATA_MISALIGNED );
rk = ctx->rk;
iw = PADLOCK_ALIGN16( buf );
memcpy( iw, iv, 16 );
ctrl = iw + 4;
*ctrl = 0x80 | ctx->nr | ( ( ctx->nr + (mode^1) - 10 ) << 9 );
count = (length + 15) >> 4;
asm( "pushfl; popfl \n" \
"movl %%ebx, %0 \n" \
"movl %2, %%ecx \n" \
"movl %3, %%edx \n" \
"movl %4, %%ebx \n" \
"movl %5, %%esi \n" \
"movl %6, %%edi \n" \
"movl %7, %%eax \n" \
".byte 0xf3,0x0f,0xa7,0xd0\n" \
"movl %1, %%ebx \n"
: "=m" (ebx)
: "m" (ebx), "m" (count), "m" (ctrl),
"m" (rk), "m" (input), "m" (output), "m" (iw)
: "eax", "ecx", "edx", "esi", "edi" );
memcpy( iv, iw, 16 );
return( 0 );
}
#endif
#endif