1 /*
2  *  VIA PadLock support functions
3  *
4  *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
5  *  SPDX-License-Identifier: Apache-2.0
6  *
7  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
8  *  not use this file except in compliance with the License.
9  *  You may obtain a copy of the License at
10  *
11  *  http://www.apache.org/licenses/LICENSE-2.0
12  *
13  *  Unless required by applicable law or agreed to in writing, software
14  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16  *  See the License for the specific language governing permissions and
17  *  limitations under the License.
18  *
19  *  This file is part of mbed TLS (https://tls.mbed.org)
20  */
21 /*
22  *  This implementation is based on the VIA PadLock Programming Guide:
23  *
24  *  http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
25  *  programming_guide.pdf
26  */
27 
28 #if !defined(MBEDTLS_CONFIG_FILE)
29 #include "mbedtls/config.h"
30 #else
31 #include MBEDTLS_CONFIG_FILE
32 #endif
33 
34 #if defined(MBEDTLS_PADLOCK_C)
35 
36 #include "mbedtls/padlock.h"
37 
38 #include <string.h>
39 
40 #ifndef asm
41 #define asm __asm
42 #endif
43 
44 #if defined(MBEDTLS_HAVE_X86)
45 
46 /*
47  * PadLock detection routine
48  */
mbedtls_padlock_has_support(int feature)49 int mbedtls_padlock_has_support( int feature )
50 {
51     static int flags = -1;
52     int ebx = 0, edx = 0;
53 
54     if( flags == -1 )
55     {
56         asm( "movl  %%ebx, %0           \n\t"
57              "movl  $0xC0000000, %%eax  \n\t"
58              "cpuid                     \n\t"
59              "cmpl  $0xC0000001, %%eax  \n\t"
60              "movl  $0, %%edx           \n\t"
61              "jb    unsupported         \n\t"
62              "movl  $0xC0000001, %%eax  \n\t"
63              "cpuid                     \n\t"
64              "unsupported:              \n\t"
65              "movl  %%edx, %1           \n\t"
66              "movl  %2, %%ebx           \n\t"
67              : "=m" (ebx), "=m" (edx)
68              :  "m" (ebx)
69              : "eax", "ecx", "edx" );
70 
71         flags = edx;
72     }
73 
74     return( flags & feature );
75 }
76 
77 /*
78  * PadLock AES-ECB block en(de)cryption
79  */
mbedtls_padlock_xcryptecb(mbedtls_aes_context * ctx,int mode,const unsigned char input[16],unsigned char output[16])80 int mbedtls_padlock_xcryptecb( mbedtls_aes_context *ctx,
81                        int mode,
82                        const unsigned char input[16],
83                        unsigned char output[16] )
84 {
85     int ebx = 0;
86     uint32_t *rk;
87     uint32_t *blk;
88     uint32_t *ctrl;
89     unsigned char buf[256];
90 
91     rk  = ctx->rk;
92     blk = MBEDTLS_PADLOCK_ALIGN16( buf );
93     memcpy( blk, input, 16 );
94 
95      ctrl = blk + 4;
96     *ctrl = 0x80 | ctx->nr | ( ( ctx->nr + ( mode^1 ) - 10 ) << 9 );
97 
98     asm( "pushfl                        \n\t"
99          "popfl                         \n\t"
100          "movl    %%ebx, %0             \n\t"
101          "movl    $1, %%ecx             \n\t"
102          "movl    %2, %%edx             \n\t"
103          "movl    %3, %%ebx             \n\t"
104          "movl    %4, %%esi             \n\t"
105          "movl    %4, %%edi             \n\t"
106          ".byte  0xf3,0x0f,0xa7,0xc8    \n\t"
107          "movl    %1, %%ebx             \n\t"
108          : "=m" (ebx)
109          :  "m" (ebx), "m" (ctrl), "m" (rk), "m" (blk)
110          : "memory", "ecx", "edx", "esi", "edi" );
111 
112     memcpy( output, blk, 16 );
113 
114     return( 0 );
115 }
116 
117 /*
118  * PadLock AES-CBC buffer en(de)cryption
119  */
mbedtls_padlock_xcryptcbc(mbedtls_aes_context * ctx,int mode,size_t length,unsigned char iv[16],const unsigned char * input,unsigned char * output)120 int mbedtls_padlock_xcryptcbc( mbedtls_aes_context *ctx,
121                        int mode,
122                        size_t length,
123                        unsigned char iv[16],
124                        const unsigned char *input,
125                        unsigned char *output )
126 {
127     int ebx = 0;
128     size_t count;
129     uint32_t *rk;
130     uint32_t *iw;
131     uint32_t *ctrl;
132     unsigned char buf[256];
133 
134     if( ( (long) input  & 15 ) != 0 ||
135         ( (long) output & 15 ) != 0 )
136         return( MBEDTLS_ERR_PADLOCK_DATA_MISALIGNED );
137 
138     rk = ctx->rk;
139     iw = MBEDTLS_PADLOCK_ALIGN16( buf );
140     memcpy( iw, iv, 16 );
141 
142      ctrl = iw + 4;
143     *ctrl = 0x80 | ctx->nr | ( ( ctx->nr + ( mode ^ 1 ) - 10 ) << 9 );
144 
145     count = ( length + 15 ) >> 4;
146 
147     asm( "pushfl                        \n\t"
148          "popfl                         \n\t"
149          "movl    %%ebx, %0             \n\t"
150          "movl    %2, %%ecx             \n\t"
151          "movl    %3, %%edx             \n\t"
152          "movl    %4, %%ebx             \n\t"
153          "movl    %5, %%esi             \n\t"
154          "movl    %6, %%edi             \n\t"
155          "movl    %7, %%eax             \n\t"
156          ".byte  0xf3,0x0f,0xa7,0xd0    \n\t"
157          "movl    %1, %%ebx             \n\t"
158          : "=m" (ebx)
159          :  "m" (ebx), "m" (count), "m" (ctrl),
160             "m"  (rk), "m" (input), "m" (output), "m" (iw)
161          : "memory", "eax", "ecx", "edx", "esi", "edi" );
162 
163     memcpy( iv, iw, 16 );
164 
165     return( 0 );
166 }
167 
168 #endif /* MBEDTLS_HAVE_X86 */
169 
170 #endif /* MBEDTLS_PADLOCK_C */
171