1 /*
2  *  VIA PadLock support functions
3  *
4  *  Copyright The Mbed TLS Contributors
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 /*
20  *  This implementation is based on the VIA PadLock Programming Guide:
21  *
22  *  http://www.via.com.tw/en/downloads/whitepapers/initiatives/padlock/
23  *  programming_guide.pdf
24  */
25 
26 #include "common.h"
27 
28 #if defined(MBEDTLS_PADLOCK_C)
29 
30 #include "padlock.h"
31 
32 #include <string.h>
33 
34 #ifndef asm
35 #define asm __asm
36 #endif
37 
38 #if defined(MBEDTLS_HAVE_X86)
39 
40 /*
41  * PadLock detection routine
42  */
mbedtls_padlock_has_support(int feature)43 int mbedtls_padlock_has_support( int feature )
44 {
45     static int flags = -1;
46     int ebx = 0, edx = 0;
47 
48     if( flags == -1 )
49     {
50         asm( "movl  %%ebx, %0           \n\t"
51              "movl  $0xC0000000, %%eax  \n\t"
52              "cpuid                     \n\t"
53              "cmpl  $0xC0000001, %%eax  \n\t"
54              "movl  $0, %%edx           \n\t"
55              "jb    1f                  \n\t"
56              "movl  $0xC0000001, %%eax  \n\t"
57              "cpuid                     \n\t"
58              "1:                        \n\t"
59              "movl  %%edx, %1           \n\t"
60              "movl  %2, %%ebx           \n\t"
61              : "=m" (ebx), "=m" (edx)
62              :  "m" (ebx)
63              : "eax", "ecx", "edx" );
64 
65         flags = edx;
66     }
67 
68     return( flags & feature );
69 }
70 
71 /*
72  * PadLock AES-ECB block en(de)cryption
73  */
mbedtls_padlock_xcryptecb(mbedtls_aes_context * ctx,int mode,const unsigned char input[16],unsigned char output[16])74 int mbedtls_padlock_xcryptecb( mbedtls_aes_context *ctx,
75                        int mode,
76                        const unsigned char input[16],
77                        unsigned char output[16] )
78 {
79     int ebx = 0;
80     uint32_t *rk;
81     uint32_t *blk;
82     uint32_t *ctrl;
83     unsigned char buf[256];
84 
85     rk  = ctx->rk;
86     blk = MBEDTLS_PADLOCK_ALIGN16( buf );
87     memcpy( blk, input, 16 );
88 
89      ctrl = blk + 4;
90     *ctrl = 0x80 | ctx->nr | ( ( ctx->nr + ( mode^1 ) - 10 ) << 9 );
91 
92     asm( "pushfl                        \n\t"
93          "popfl                         \n\t"
94          "movl    %%ebx, %0             \n\t"
95          "movl    $1, %%ecx             \n\t"
96          "movl    %2, %%edx             \n\t"
97          "movl    %3, %%ebx             \n\t"
98          "movl    %4, %%esi             \n\t"
99          "movl    %4, %%edi             \n\t"
100          ".byte  0xf3,0x0f,0xa7,0xc8    \n\t"
101          "movl    %1, %%ebx             \n\t"
102          : "=m" (ebx)
103          :  "m" (ebx), "m" (ctrl), "m" (rk), "m" (blk)
104          : "memory", "ecx", "edx", "esi", "edi" );
105 
106     memcpy( output, blk, 16 );
107 
108     return( 0 );
109 }
110 
111 /*
112  * PadLock AES-CBC buffer en(de)cryption
113  */
mbedtls_padlock_xcryptcbc(mbedtls_aes_context * ctx,int mode,size_t length,unsigned char iv[16],const unsigned char * input,unsigned char * output)114 int mbedtls_padlock_xcryptcbc( mbedtls_aes_context *ctx,
115                        int mode,
116                        size_t length,
117                        unsigned char iv[16],
118                        const unsigned char *input,
119                        unsigned char *output )
120 {
121     int ebx = 0;
122     size_t count;
123     uint32_t *rk;
124     uint32_t *iw;
125     uint32_t *ctrl;
126     unsigned char buf[256];
127 
128     if( ( (long) input  & 15 ) != 0 ||
129         ( (long) output & 15 ) != 0 )
130         return( MBEDTLS_ERR_PADLOCK_DATA_MISALIGNED );
131 
132     rk = ctx->rk;
133     iw = MBEDTLS_PADLOCK_ALIGN16( buf );
134     memcpy( iw, iv, 16 );
135 
136      ctrl = iw + 4;
137     *ctrl = 0x80 | ctx->nr | ( ( ctx->nr + ( mode ^ 1 ) - 10 ) << 9 );
138 
139     count = ( length + 15 ) >> 4;
140 
141     asm( "pushfl                        \n\t"
142          "popfl                         \n\t"
143          "movl    %%ebx, %0             \n\t"
144          "movl    %2, %%ecx             \n\t"
145          "movl    %3, %%edx             \n\t"
146          "movl    %4, %%ebx             \n\t"
147          "movl    %5, %%esi             \n\t"
148          "movl    %6, %%edi             \n\t"
149          "movl    %7, %%eax             \n\t"
150          ".byte  0xf3,0x0f,0xa7,0xd0    \n\t"
151          "movl    %1, %%ebx             \n\t"
152          : "=m" (ebx)
153          :  "m" (ebx), "m" (count), "m" (ctrl),
154             "m"  (rk), "m" (input), "m" (output), "m" (iw)
155          : "memory", "eax", "ecx", "edx", "esi", "edi" );
156 
157     memcpy( iv, iw, 16 );
158 
159     return( 0 );
160 }
161 
162 #endif /* MBEDTLS_HAVE_X86 */
163 
164 #endif /* MBEDTLS_PADLOCK_C */
165