padlock.c

00001 /*
00002  *  VIA PadLock support functions
00003  *
00004  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
00005  *  SPDX-License-Identifier: Apache-2.0
00006  *
00007  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
00008  *  not use this file except in compliance with the License.
00009  *  You may obtain a copy of the License at
00010  *
00011  *  http://www.apache.org/licenses/LICENSE-2.0
00012  *
00013  *  Unless required by applicable law or agreed to in writing, software
00014  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
00015  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
00016  *  See the License for the specific language governing permissions and
00017  *  limitations under the License.
00018  *
00019  *  This file is part of mbed TLS (https://tls.mbed.org)
00020  */
00021 /*
00022  *  This implementation is based on the VIA PadLock Programming Guide:
00023  *
00024  *  http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
00025  *  programming_guide.pdf
00026  */
00027 
00028 #if !defined(MBEDTLS_CONFIG_FILE)
00029 #include "mbedtls/config.h"
00030 #else
00031 #include MBEDTLS_CONFIG_FILE
00032 #endif
00033 
00034 #if defined(MBEDTLS_PADLOCK_C)
00035 
00036 #include "mbedtls/padlock.h"
00037 
00038 #include <string.h>
00039 
00040 #ifndef asm
00041 #define asm __asm
00042 #endif
00043 
00044 #if defined(MBEDTLS_HAVE_X86)
00045 
00046 /*
00047  * PadLock detection routine
00048  */
00049 int mbedtls_padlock_has_support( int feature )
00050 {
00051     static int flags = -1;
00052     int ebx = 0, edx = 0;
00053 
00054     if( flags == -1 )
00055     {
00056         asm( "movl  %%ebx, %0           \n\t"
00057              "movl  $0xC0000000, %%eax  \n\t"
00058              "cpuid                     \n\t"
00059              "cmpl  $0xC0000001, %%eax  \n\t"
00060              "movl  $0, %%edx           \n\t"
00061              "jb    unsupported         \n\t"
00062              "movl  $0xC0000001, %%eax  \n\t"
00063              "cpuid                     \n\t"
00064              "unsupported:              \n\t"
00065              "movl  %%edx, %1           \n\t"
00066              "movl  %2, %%ebx           \n\t"
00067              : "=m" (ebx), "=m" (edx)
00068              :  "m" (ebx)
00069              : "eax", "ecx", "edx" );
00070 
00071         flags = edx;
00072     }
00073 
00074     return( flags & feature );
00075 }
00076 
00077 /*
00078  * PadLock AES-ECB block en(de)cryption
00079  */
00080 int mbedtls_padlock_xcryptecb( mbedtls_aes_context *ctx,
00081                        int mode,
00082                        const unsigned char input[16],
00083                        unsigned char output[16] )
00084 {
00085     int ebx = 0;
00086     uint32_t *rk;
00087     uint32_t *blk;
00088     uint32_t *ctrl;
00089     unsigned char buf[256];
00090 
00091     rk  = ctx->rk ;
00092     blk = MBEDTLS_PADLOCK_ALIGN16( buf );
00093     memcpy( blk, input, 16 );
00094 
00095      ctrl = blk + 4;
00096     *ctrl = 0x80 | ctx->nr  | ( ( ctx->nr  + ( mode^1 ) - 10 ) << 9 );
00097 
00098     asm( "pushfl                        \n\t"
00099          "popfl                         \n\t"
00100          "movl    %%ebx, %0             \n\t"
00101          "movl    $1, %%ecx             \n\t"
00102          "movl    %2, %%edx             \n\t"
00103          "movl    %3, %%ebx             \n\t"
00104          "movl    %4, %%esi             \n\t"
00105          "movl    %4, %%edi             \n\t"
00106          ".byte  0xf3,0x0f,0xa7,0xc8    \n\t"
00107          "movl    %1, %%ebx             \n\t"
00108          : "=m" (ebx)
00109          :  "m" (ebx), "m" (ctrl), "m" (rk), "m" (blk)
00110          : "memory", "ecx", "edx", "esi", "edi" );
00111 
00112     memcpy( output, blk, 16 );
00113 
00114     return( 0 );
00115 }
00116 
00117 /*
00118  * PadLock AES-CBC buffer en(de)cryption
00119  */
00120 int mbedtls_padlock_xcryptcbc( mbedtls_aes_context *ctx,
00121                        int mode,
00122                        size_t length,
00123                        unsigned char iv[16],
00124                        const unsigned char *input,
00125                        unsigned char *output )
00126 {
00127     int ebx = 0;
00128     size_t count;
00129     uint32_t *rk;
00130     uint32_t *iw;
00131     uint32_t *ctrl;
00132     unsigned char buf[256];
00133 
00134     if( ( (long) input  & 15 ) != 0 ||
00135         ( (long) output & 15 ) != 0 )
00136         return( MBEDTLS_ERR_PADLOCK_DATA_MISALIGNED );
00137 
00138     rk = ctx->rk ;
00139     iw = MBEDTLS_PADLOCK_ALIGN16( buf );
00140     memcpy( iw, iv, 16 );
00141 
00142      ctrl = iw + 4;
00143     *ctrl = 0x80 | ctx->nr  | ( ( ctx->nr  + ( mode ^ 1 ) - 10 ) << 9 );
00144 
00145     count = ( length + 15 ) >> 4;
00146 
00147     asm( "pushfl                        \n\t"
00148          "popfl                         \n\t"
00149          "movl    %%ebx, %0             \n\t"
00150          "movl    %2, %%ecx             \n\t"
00151          "movl    %3, %%edx             \n\t"
00152          "movl    %4, %%ebx             \n\t"
00153          "movl    %5, %%esi             \n\t"
00154          "movl    %6, %%edi             \n\t"
00155          "movl    %7, %%eax             \n\t"
00156          ".byte  0xf3,0x0f,0xa7,0xd0    \n\t"
00157          "movl    %1, %%ebx             \n\t"
00158          : "=m" (ebx)
00159          :  "m" (ebx), "m" (count), "m" (ctrl),
00160             "m"  (rk), "m" (input), "m" (output), "m" (iw)
00161          : "memory", "eax", "ecx", "edx", "esi", "edi" );
00162 
00163     memcpy( iv, iw, 16 );
00164 
00165     return( 0 );
00166 }
00167 
00168 #endif /* MBEDTLS_HAVE_X86 */
00169 
00170 #endif /* MBEDTLS_PADLOCK_C */