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
|
/*
* Copyright 1998-2022 The OpenSSL Project Authors. All Rights Reserved.
*
* Licensed under the Apache License 2.0 (the "License"). You may not use
* this file except in compliance with the License. You can obtain a copy
* in the file LICENSE in the source distribution or at
* https://www.openssl.org/source/license.html
*/
#include "internal/e_os.h"
#include "crypto/cryptlib.h"
#if defined(__i386) || defined(__i386__) || defined(_M_IX86) || \
defined(__x86_64) || defined(__x86_64__) || \
defined(_M_AMD64) || defined(_M_X64)
extern unsigned int OPENSSL_ia32cap_P[4];
# if defined(OPENSSL_CPUID_OBJ)
/*
* Purpose of these minimalistic and character-type-agnostic subroutines
* is to break dependency on MSVCRT (on Windows) and locale. This makes
* OPENSSL_cpuid_setup safe to use as "constructor". "Character-type-
* agnostic" means that they work with either wide or 8-bit characters,
* exploiting the fact that first 127 characters can be simply casted
* between the sets, while the rest would be simply rejected by ossl_is*
* subroutines.
*/
# ifdef _WIN32
typedef WCHAR variant_char;
static variant_char *ossl_getenv(const char *name)
{
/*
* Since we pull only one environment variable, it's simpler to
* to just ignore |name| and use equivalent wide-char L-literal.
* As well as to ignore excessively long values...
*/
static WCHAR value[48];
DWORD len = GetEnvironmentVariableW(L"OPENSSL_ia32cap", value, 48);
return (len > 0 && len < 48) ? value : NULL;
}
# else
typedef char variant_char;
# define ossl_getenv getenv
# endif
# include "crypto/ctype.h"
static int todigit(variant_char c)
{
if (ossl_isdigit(c))
return c - '0';
else if (ossl_isxdigit(c))
return ossl_tolower(c) - 'a' + 10;
/* return largest base value to make caller terminate the loop */
return 16;
}
static uint64_t ossl_strtouint64(const variant_char *str)
{
uint64_t ret = 0;
unsigned int digit, base = 10;
if (*str == '0') {
base = 8, str++;
if (ossl_tolower(*str) == 'x')
base = 16, str++;
}
while ((digit = todigit(*str++)) < base)
ret = ret * base + digit;
return ret;
}
static variant_char *ossl_strchr(const variant_char *str, char srch)
{ variant_char c;
while ((c = *str)) {
if (c == srch)
return (variant_char *)str;
str++;
}
return NULL;
}
# define OPENSSL_CPUID_SETUP
typedef uint64_t IA32CAP;
void OPENSSL_cpuid_setup(void)
{
static int trigger = 0;
IA32CAP OPENSSL_ia32_cpuid(unsigned int *);
IA32CAP vec;
const variant_char *env;
if (trigger)
return;
trigger = 1;
if ((env = ossl_getenv("OPENSSL_ia32cap")) != NULL) {
int off = (env[0] == '~') ? 1 : 0;
vec = ossl_strtouint64(env + off);
if (off) {
IA32CAP mask = vec;
vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P) & ~mask;
if (mask & (1<<24)) {
/*
* User disables FXSR bit, mask even other capabilities
* that operate exclusively on XMM, so we don't have to
* double-check all the time. We mask PCLMULQDQ, AMD XOP,
* AES-NI and AVX. Formally speaking we don't have to
* do it in x86_64 case, but we can safely assume that
* x86_64 users won't actually flip this flag.
*/
vec &= ~((IA32CAP)(1<<1|1<<11|1<<25|1<<28) << 32);
}
} else if (env[0] == ':') {
vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P);
}
if ((env = ossl_strchr(env, ':')) != NULL) {
IA32CAP vecx;
env++;
off = (env[0] == '~') ? 1 : 0;
vecx = ossl_strtouint64(env + off);
if (off) {
OPENSSL_ia32cap_P[2] &= ~(unsigned int)vecx;
OPENSSL_ia32cap_P[3] &= ~(unsigned int)(vecx >> 32);
} else {
OPENSSL_ia32cap_P[2] = (unsigned int)vecx;
OPENSSL_ia32cap_P[3] = (unsigned int)(vecx >> 32);
}
} else {
OPENSSL_ia32cap_P[2] = 0;
OPENSSL_ia32cap_P[3] = 0;
}
} else {
vec = OPENSSL_ia32_cpuid(OPENSSL_ia32cap_P);
}
/*
* |(1<<10) sets a reserved bit to signal that variable
* was initialized already... This is to avoid interference
* with cpuid snippets in ELF .init segment.
*/
OPENSSL_ia32cap_P[0] = (unsigned int)vec | (1 << 10);
OPENSSL_ia32cap_P[1] = (unsigned int)(vec >> 32);
}
# else
unsigned int OPENSSL_ia32cap_P[4];
# endif
#endif
#ifndef OPENSSL_CPUID_OBJ
# ifndef OPENSSL_CPUID_SETUP
void OPENSSL_cpuid_setup(void)
{
}
# endif
/*
* The rest are functions that are defined in the same assembler files as
* the CPUID functionality.
*/
/*
* The volatile is used to to ensure that the compiler generates code that reads
* all values from the array and doesn't try to optimize this away. The standard
* doesn't actually require this behavior if the original data pointed to is
* not volatile, but compilers do this in practice anyway.
*
* There are also assembler versions of this function.
*/
# undef CRYPTO_memcmp
int CRYPTO_memcmp(const void * in_a, const void * in_b, size_t len)
{
size_t i;
const volatile unsigned char *a = in_a;
const volatile unsigned char *b = in_b;
unsigned char x = 0;
for (i = 0; i < len; i++)
x |= a[i] ^ b[i];
return x;
}
/*
* For systems that don't provide an instruction counter register or equivalent.
*/
uint32_t OPENSSL_rdtsc(void)
{
return 0;
}
size_t OPENSSL_instrument_bus(unsigned int *out, size_t cnt)
{
return 0;
}
size_t OPENSSL_instrument_bus2(unsigned int *out, size_t cnt, size_t max)
{
return 0;
}
#endif
|
