1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
|
/* hwf-x86.c - Detect hardware features - x86 part
* Copyright (C) 2007, 2011, 2012 Free Software Foundation, Inc.
* Copyright (C) 2012 Jussi Kivilinna
*
* This file is part of Libgcrypt.
*
* Libgcrypt is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* Libgcrypt 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <stdarg.h>
#include <unistd.h>
#include "g10lib.h"
#include "hwf-common.h"
#if !defined (__i386__) && !defined (__x86_64__)
# error Module build for wrong CPU.
#endif
/* We use the next macro to decide whether we can test for certain
features. */
#undef HAS_X86_CPUID
#if defined (__i386__) && SIZEOF_UNSIGNED_LONG == 4 && defined (__GNUC__)
# define HAS_X86_CPUID 1
static int
is_cpuid_available(void)
{
int has_cpuid = 0;
/* Detect the CPUID feature by testing some undefined behaviour (16
vs 32 bit pushf/popf). */
asm volatile
("pushf\n\t" /* Copy flags to EAX. */
"popl %%eax\n\t"
"movl %%eax, %%ecx\n\t" /* Save flags into ECX. */
"xorl $0x200000, %%eax\n\t" /* Toggle ID bit and copy it to the flags. */
"pushl %%eax\n\t"
"popf\n\t"
"pushf\n\t" /* Copy changed flags again to EAX. */
"popl %%eax\n\t"
"pushl %%ecx\n\t" /* Restore flags from ECX. */
"popf\n\t"
"xorl %%eax, %%ecx\n\t" /* Compare flags against saved flags. */
"jz .Lno_cpuid%=\n\t" /* Toggling did not work, thus no CPUID. */
"movl $1, %0\n" /* Worked. true -> HAS_CPUID. */
".Lno_cpuid%=:\n\t"
: "+r" (has_cpuid)
:
: "%eax", "%ecx", "cc"
);
return has_cpuid;
}
static void
get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
unsigned int regs[4];
asm volatile
("pushl %%ebx\n\t" /* Save GOT register. */
"cpuid\n\t"
"movl %%ebx, %1\n\t"
"popl %%ebx\n\t" /* Restore GOT register. */
: "=a" (regs[0]), "=r" (regs[1]), "=c" (regs[2]), "=d" (regs[3])
: "0" (in)
: "cc"
);
if (eax)
*eax = regs[0];
if (ebx)
*ebx = regs[1];
if (ecx)
*ecx = regs[2];
if (edx)
*edx = regs[3];
}
#endif /* i386 && GNUC */
#if defined (__x86_64__) && defined (__GNUC__)
# define HAS_X86_CPUID 1
static int
is_cpuid_available(void)
{
return 1;
}
static void
get_cpuid(unsigned int in, unsigned int *eax, unsigned int *ebx,
unsigned int *ecx, unsigned int *edx)
{
unsigned int regs[4];
asm volatile
("cpuid\n\t"
: "=a" (regs[0]), "=b" (regs[1]), "=c" (regs[2]), "=d" (regs[3])
: "0" (in)
: "cc"
);
if (eax)
*eax = regs[0];
if (ebx)
*ebx = regs[1];
if (ecx)
*ecx = regs[2];
if (edx)
*edx = regs[3];
}
#endif /* x86-64 && GNUC */
#ifdef HAS_X86_CPUID
static unsigned int
detect_x86_gnuc (void)
{
char vendor_id[12+1];
unsigned int features;
unsigned int result = 0;
if (!is_cpuid_available())
return 0;
get_cpuid(0, NULL,
(unsigned int *)&vendor_id[0],
(unsigned int *)&vendor_id[8],
(unsigned int *)&vendor_id[4]);
vendor_id[12] = 0;
if (0)
; /* Just to make "else if" and ifdef macros look pretty. */
#ifdef ENABLE_PADLOCK_SUPPORT
else if (!strcmp (vendor_id, "CentaurHauls"))
{
/* This is a VIA CPU. Check what PadLock features we have. */
/* Check for extended centaur (EAX). */
get_cpuid(0xC0000000, &features, NULL, NULL, NULL);
/* Has extended centaur features? */
if (features > 0xC0000000)
{
/* Ask for the extended feature flags (EDX). */
get_cpuid(0xC0000001, NULL, NULL, NULL, &features);
/* Test bits 2 and 3 to see whether the RNG exists and is enabled. */
if ((features & 0x0C) == 0x0C)
result |= HWF_PADLOCK_RNG;
/* Test bits 6 and 7 to see whether the ACE exists and is enabled. */
if ((features & 0xC0) == 0xC0)
result |= HWF_PADLOCK_AES;
/* Test bits 10 and 11 to see whether the PHE exists and is
enabled. */
if ((features & 0xC00) == 0xC00)
result |= HWF_PADLOCK_SHA;
/* Test bits 12 and 13 to see whether the MONTMUL exists and is
enabled. */
if ((features & 0x3000) == 0x3000)
result |= HWF_PADLOCK_MMUL;
}
}
#endif /*ENABLE_PADLOCK_SUPPORT*/
else if (!strcmp (vendor_id, "GenuineIntel"))
{
/* This is an Intel CPU. */
}
else if (!strcmp (vendor_id, "AuthenticAMD"))
{
/* This is an AMD CPU. */
}
/* Detect Intel features, that might also be supported by other
vendors. */
/* Get CPU info and Intel feature flags (ECX). */
get_cpuid(1, NULL, NULL, &features, NULL);
#ifdef ENABLE_AESNI_SUPPORT
/* Test bit 25 for AES-NI. */
if (features & 0x02000000)
result |= HWF_INTEL_AESNI;
#endif /*ENABLE_AESNI_SUPPORT*/
#ifdef ENABLE_AVX_SUPPORT
/* Test bit 28 for AVX. */
if (features & 0x10000000)
result |= HWF_INTEL_AVX;
#endif /*ENABLE_AVX_SUPPORT*/
#ifdef ENABLE_DRNG_SUPPORT
/* Test bit 30 for RDRAND. */
if (features & 0x40000000)
result |= HWF_INTEL_RDRAND;
#endif /*ENABLE_DRNG_SUPPORT*/
return result;
}
#endif /* HAS_X86_CPUID */
unsigned int
_gcry_hwf_detect_x86 (void)
{
#if defined (HAS_X86_CPUID)
return detect_x86_gnuc ();
#else
return 0;
#endif
}
|
