/*
 *  VIA PadLock support functions
 *
 *  Based on XySSL: Copyright (C) 2006-2008  Christophe Devine
 *
 *  Copyright (C) 2009  Paul Bakker <polarssl_maintainer at polarssl dot org>
 *
 *  All rights reserved.
 *
 *  Redistribution and use in source and binary forms, with or without
 *  modification, are permitted provided that the following conditions
 *  are met:
 *  
 *    * Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *    * Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *    * Neither the names of PolarSSL or XySSL nor the names of its contributors
 *      may be used to endorse or promote products derived from this software
 *      without specific prior written permission.
 *  
 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *  "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *  LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
 *  FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *  OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
 *  TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 *  PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/*
 *  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,
                       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],
                       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( 1 );

    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