1 | /*
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2 | * Portable interface to the CPU cycle counter
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3 | *
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4 | * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
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5 | * SPDX-License-Identifier: Apache-2.0
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6 | *
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7 | * Licensed under the Apache License, Version 2.0 (the "License"); you may
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8 | * not use this file except in compliance with the License.
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9 | * You may obtain a copy of the License at
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10 | *
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11 | * http://www.apache.org/licenses/LICENSE-2.0
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12 | *
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13 | * Unless required by applicable law or agreed to in writing, software
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14 | * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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15 | * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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16 | * See the License for the specific language governing permissions and
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17 | * limitations under the License.
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18 | *
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19 | * This file is part of mbed TLS (https://tls.mbed.org)
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20 | */
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21 |
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22 | #if !defined(MBEDTLS_CONFIG_FILE)
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23 | #include "mbedtls/config.h"
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24 | #else
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25 | #include MBEDTLS_CONFIG_FILE
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26 | #endif
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27 |
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28 | #if defined(MBEDTLS_SELF_TEST) && defined(MBEDTLS_PLATFORM_C)
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29 | #include "mbedtls/platform.h"
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30 | #else
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31 | #include <stdio.h>
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32 | #define mbedtls_printf printf
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33 | #endif
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34 |
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35 | #if defined(MBEDTLS_TIMING_C)
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36 |
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37 | #include "mbedtls/timing.h"
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38 |
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39 | #if !defined(MBEDTLS_TIMING_ALT)
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40 |
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41 | #if !defined(unix) && !defined(__unix__) && !defined(__unix) && \
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42 | !defined(__APPLE__) && !defined(_WIN32) && !defined(__QNXNTO__) && \
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43 | !defined(__HAIKU__)
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44 | #error "This module only works on Unix and Windows, see MBEDTLS_TIMING_C in config.h"
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45 | #endif
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46 |
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47 | #ifndef asm
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48 | #define asm __asm
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49 | #endif
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50 |
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51 | #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
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52 |
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53 | #include <windows.h>
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54 | #include <winbase.h>
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55 | #include <process.h>
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56 |
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57 | struct _hr_time
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58 | {
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59 | LARGE_INTEGER start;
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60 | };
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61 |
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62 | #else
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63 |
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64 | #include <unistd.h>
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65 | #include <sys/types.h>
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66 | #include <sys/time.h>
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67 | #include <signal.h>
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68 | #include <time.h>
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69 |
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70 | struct _hr_time
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71 | {
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72 | struct timeval start;
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73 | };
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74 |
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75 | #endif /* _WIN32 && !EFIX64 && !EFI32 */
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76 |
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77 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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78 | ( defined(_MSC_VER) && defined(_M_IX86) ) || defined(__WATCOMC__)
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79 |
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80 | #define HAVE_HARDCLOCK
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81 |
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82 | unsigned long mbedtls_timing_hardclock( void )
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83 | {
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84 | unsigned long tsc;
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85 | __asm rdtsc
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86 | __asm mov [tsc], eax
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87 | return( tsc );
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88 | }
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89 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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90 | ( _MSC_VER && _M_IX86 ) || __WATCOMC__ */
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91 |
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92 | /* some versions of mingw-64 have 32-bit longs even on x84_64 */
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93 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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94 | defined(__GNUC__) && ( defined(__i386__) || ( \
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95 | ( defined(__amd64__) || defined( __x86_64__) ) && __SIZEOF_LONG__ == 4 ) )
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96 |
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97 | #define HAVE_HARDCLOCK
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98 |
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99 | unsigned long mbedtls_timing_hardclock( void )
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100 | {
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101 | unsigned long lo, hi;
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102 | asm volatile( "rdtsc" : "=a" (lo), "=d" (hi) );
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103 | return( lo );
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104 | }
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105 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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106 | __GNUC__ && __i386__ */
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107 |
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108 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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109 | defined(__GNUC__) && ( defined(__amd64__) || defined(__x86_64__) )
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110 |
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111 | #define HAVE_HARDCLOCK
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112 |
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113 | unsigned long mbedtls_timing_hardclock( void )
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114 | {
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115 | unsigned long lo, hi;
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116 | asm volatile( "rdtsc" : "=a" (lo), "=d" (hi) );
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117 | return( lo | ( hi << 32 ) );
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118 | }
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119 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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120 | __GNUC__ && ( __amd64__ || __x86_64__ ) */
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121 |
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122 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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123 | defined(__GNUC__) && ( defined(__powerpc__) || defined(__ppc__) )
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124 |
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125 | #define HAVE_HARDCLOCK
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126 |
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127 | unsigned long mbedtls_timing_hardclock( void )
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128 | {
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129 | unsigned long tbl, tbu0, tbu1;
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130 |
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131 | do
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132 | {
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133 | asm volatile( "mftbu %0" : "=r" (tbu0) );
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134 | asm volatile( "mftb %0" : "=r" (tbl ) );
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135 | asm volatile( "mftbu %0" : "=r" (tbu1) );
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136 | }
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137 | while( tbu0 != tbu1 );
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138 |
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139 | return( tbl );
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140 | }
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141 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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142 | __GNUC__ && ( __powerpc__ || __ppc__ ) */
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143 |
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144 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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145 | defined(__GNUC__) && defined(__sparc64__)
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146 |
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147 | #if defined(__OpenBSD__)
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148 | #warning OpenBSD does not allow access to tick register using software version instead
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149 | #else
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150 | #define HAVE_HARDCLOCK
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151 |
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152 | unsigned long mbedtls_timing_hardclock( void )
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153 | {
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154 | unsigned long tick;
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155 | asm volatile( "rdpr %%tick, %0;" : "=&r" (tick) );
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156 | return( tick );
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157 | }
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158 | #endif /* __OpenBSD__ */
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159 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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160 | __GNUC__ && __sparc64__ */
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161 |
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162 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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163 | defined(__GNUC__) && defined(__sparc__) && !defined(__sparc64__)
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164 |
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165 | #define HAVE_HARDCLOCK
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166 |
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167 | unsigned long mbedtls_timing_hardclock( void )
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168 | {
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169 | unsigned long tick;
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170 | asm volatile( ".byte 0x83, 0x41, 0x00, 0x00" );
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171 | asm volatile( "mov %%g1, %0" : "=r" (tick) );
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172 | return( tick );
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173 | }
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174 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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175 | __GNUC__ && __sparc__ && !__sparc64__ */
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176 |
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177 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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178 | defined(__GNUC__) && defined(__alpha__)
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179 |
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180 | #define HAVE_HARDCLOCK
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181 |
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182 | unsigned long mbedtls_timing_hardclock( void )
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183 | {
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184 | unsigned long cc;
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185 | asm volatile( "rpcc %0" : "=r" (cc) );
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186 | return( cc & 0xFFFFFFFF );
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187 | }
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188 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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189 | __GNUC__ && __alpha__ */
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190 |
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191 | #if !defined(HAVE_HARDCLOCK) && defined(MBEDTLS_HAVE_ASM) && \
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192 | defined(__GNUC__) && defined(__ia64__)
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193 |
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194 | #define HAVE_HARDCLOCK
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195 |
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196 | unsigned long mbedtls_timing_hardclock( void )
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197 | {
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198 | unsigned long itc;
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199 | asm volatile( "mov %0 = ar.itc" : "=r" (itc) );
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200 | return( itc );
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201 | }
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202 | #endif /* !HAVE_HARDCLOCK && MBEDTLS_HAVE_ASM &&
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203 | __GNUC__ && __ia64__ */
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204 |
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205 | #if !defined(HAVE_HARDCLOCK) && defined(_MSC_VER) && \
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206 | !defined(EFIX64) && !defined(EFI32)
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207 |
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208 | #define HAVE_HARDCLOCK
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209 |
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210 | unsigned long mbedtls_timing_hardclock( void )
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211 | {
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212 | LARGE_INTEGER offset;
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213 |
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214 | QueryPerformanceCounter( &offset );
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215 |
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216 | return( (unsigned long)( offset.QuadPart ) );
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217 | }
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218 | #endif /* !HAVE_HARDCLOCK && _MSC_VER && !EFIX64 && !EFI32 */
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219 |
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220 | #if !defined(HAVE_HARDCLOCK)
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221 |
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222 | #define HAVE_HARDCLOCK
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223 |
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224 | static int hardclock_init = 0;
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225 | static struct timeval tv_init;
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226 |
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227 | unsigned long mbedtls_timing_hardclock( void )
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228 | {
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229 | struct timeval tv_cur;
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230 |
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231 | if( hardclock_init == 0 )
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232 | {
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233 | gettimeofday( &tv_init, NULL );
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234 | hardclock_init = 1;
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235 | }
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236 |
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237 | gettimeofday( &tv_cur, NULL );
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238 | return( ( tv_cur.tv_sec - tv_init.tv_sec ) * 1000000
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239 | + ( tv_cur.tv_usec - tv_init.tv_usec ) );
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240 | }
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241 | #endif /* !HAVE_HARDCLOCK */
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242 |
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243 | volatile int mbedtls_timing_alarmed = 0;
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244 |
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245 | #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
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246 |
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247 | unsigned long mbedtls_timing_get_timer( struct mbedtls_timing_hr_time *val, int reset )
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248 | {
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249 | struct _hr_time *t = (struct _hr_time *) val;
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250 |
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251 | if( reset )
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252 | {
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253 | QueryPerformanceCounter( &t->start );
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254 | return( 0 );
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255 | }
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256 | else
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257 | {
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258 | unsigned long delta;
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259 | LARGE_INTEGER now, hfreq;
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260 | QueryPerformanceCounter( &now );
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261 | QueryPerformanceFrequency( &hfreq );
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262 | delta = (unsigned long)( ( now.QuadPart - t->start.QuadPart ) * 1000ul
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263 | / hfreq.QuadPart );
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264 | return( delta );
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265 | }
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266 | }
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267 |
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268 | /* It's OK to use a global because alarm() is supposed to be global anyway */
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269 | static DWORD alarmMs;
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270 |
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271 | static void TimerProc( void *TimerContext )
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272 | {
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273 | (void) TimerContext;
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274 | Sleep( alarmMs );
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275 | mbedtls_timing_alarmed = 1;
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276 | /* _endthread will be called implicitly on return
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277 | * That ensures execution of thread funcition's epilogue */
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278 | }
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279 |
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280 | void mbedtls_set_alarm( int seconds )
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281 | {
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282 | if( seconds == 0 )
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283 | {
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284 | /* No need to create a thread for this simple case.
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285 | * Also, this shorcut is more reliable at least on MinGW32 */
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286 | mbedtls_timing_alarmed = 1;
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287 | return;
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288 | }
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289 |
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290 | mbedtls_timing_alarmed = 0;
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291 | alarmMs = seconds * 1000;
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292 | (void) _beginthread( TimerProc, 0, NULL );
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293 | }
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294 |
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295 | #else /* _WIN32 && !EFIX64 && !EFI32 */
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296 |
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297 | unsigned long mbedtls_timing_get_timer( struct mbedtls_timing_hr_time *val, int reset )
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298 | {
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299 | struct _hr_time *t = (struct _hr_time *) val;
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300 |
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301 | if( reset )
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302 | {
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303 | gettimeofday( &t->start, NULL );
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304 | return( 0 );
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305 | }
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306 | else
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307 | {
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308 | unsigned long delta;
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309 | struct timeval now;
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310 | gettimeofday( &now, NULL );
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311 | delta = ( now.tv_sec - t->start.tv_sec ) * 1000ul
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312 | + ( now.tv_usec - t->start.tv_usec ) / 1000;
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313 | return( delta );
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314 | }
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315 | }
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316 |
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317 | static void sighandler( int signum )
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318 | {
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319 | mbedtls_timing_alarmed = 1;
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320 | signal( signum, sighandler );
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321 | }
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322 |
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323 | void mbedtls_set_alarm( int seconds )
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324 | {
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325 | mbedtls_timing_alarmed = 0;
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326 | signal( SIGALRM, sighandler );
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327 | alarm( seconds );
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328 | if( seconds == 0 )
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329 | {
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330 | /* alarm(0) cancelled any previous pending alarm, but the
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331 | handler won't fire, so raise the flag straight away. */
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332 | mbedtls_timing_alarmed = 1;
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333 | }
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334 | }
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335 |
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336 | #endif /* _WIN32 && !EFIX64 && !EFI32 */
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337 |
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338 | /*
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339 | * Set delays to watch
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340 | */
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341 | void mbedtls_timing_set_delay( void *data, uint32_t int_ms, uint32_t fin_ms )
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342 | {
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343 | mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data;
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344 |
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345 | ctx->int_ms = int_ms;
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346 | ctx->fin_ms = fin_ms;
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347 |
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348 | if( fin_ms != 0 )
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349 | (void) mbedtls_timing_get_timer( &ctx->timer, 1 );
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350 | }
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351 |
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352 | /*
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353 | * Get number of delays expired
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354 | */
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355 | int mbedtls_timing_get_delay( void *data )
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356 | {
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357 | mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data;
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358 | unsigned long elapsed_ms;
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359 |
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360 | if( ctx->fin_ms == 0 )
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361 | return( -1 );
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362 |
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363 | elapsed_ms = mbedtls_timing_get_timer( &ctx->timer, 0 );
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364 |
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365 | if( elapsed_ms >= ctx->fin_ms )
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366 | return( 2 );
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367 |
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368 | if( elapsed_ms >= ctx->int_ms )
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369 | return( 1 );
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370 |
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371 | return( 0 );
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372 | }
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373 |
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374 | #endif /* !MBEDTLS_TIMING_ALT */
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375 |
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376 | #if defined(MBEDTLS_SELF_TEST)
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377 |
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378 | /*
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379 | * Busy-waits for the given number of milliseconds.
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380 | * Used for testing mbedtls_timing_hardclock.
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381 | */
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382 | static void busy_msleep( unsigned long msec )
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383 | {
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384 | struct mbedtls_timing_hr_time hires;
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385 | unsigned long i = 0; /* for busy-waiting */
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386 | volatile unsigned long j; /* to prevent optimisation */
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387 |
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388 | (void) mbedtls_timing_get_timer( &hires, 1 );
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389 |
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390 | while( mbedtls_timing_get_timer( &hires, 0 ) < msec )
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391 | i++;
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392 |
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393 | j = i;
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394 | (void) j;
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395 | }
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396 |
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397 | #define FAIL do \
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398 | { \
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399 | if( verbose != 0 ) \
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400 | { \
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401 | mbedtls_printf( "failed at line %d\n", __LINE__ ); \
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402 | mbedtls_printf( " cycles=%lu ratio=%lu millisecs=%lu secs=%lu hardfail=%d a=%lu b=%lu\n", \
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403 | cycles, ratio, millisecs, secs, hardfail, \
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404 | (unsigned long) a, (unsigned long) b ); \
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405 | mbedtls_printf( " elapsed(hires)=%lu elapsed(ctx)=%lu status(ctx)=%d\n", \
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406 | mbedtls_timing_get_timer( &hires, 0 ), \
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407 | mbedtls_timing_get_timer( &ctx.timer, 0 ), \
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408 | mbedtls_timing_get_delay( &ctx ) ); \
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409 | } \
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410 | return( 1 ); \
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411 | } while( 0 )
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412 |
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413 | /*
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414 | * Checkup routine
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415 | *
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416 | * Warning: this is work in progress, some tests may not be reliable enough
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417 | * yet! False positives may happen.
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418 | */
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419 | int mbedtls_timing_self_test( int verbose )
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420 | {
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421 | unsigned long cycles = 0, ratio = 0;
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422 | unsigned long millisecs = 0, secs = 0;
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423 | int hardfail = 0;
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424 | struct mbedtls_timing_hr_time hires;
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425 | uint32_t a = 0, b = 0;
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426 | mbedtls_timing_delay_context ctx;
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427 |
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428 | if( verbose != 0 )
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429 | mbedtls_printf( " TIMING tests note: will take some time!\n" );
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430 |
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431 | if( verbose != 0 )
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432 | mbedtls_printf( " TIMING test #1 (set_alarm / get_timer): " );
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433 |
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434 | {
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435 | secs = 1;
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436 |
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437 | (void) mbedtls_timing_get_timer( &hires, 1 );
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438 |
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439 | mbedtls_set_alarm( (int) secs );
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440 | while( !mbedtls_timing_alarmed )
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441 | ;
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442 |
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443 | millisecs = mbedtls_timing_get_timer( &hires, 0 );
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444 |
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445 | /* For some reason on Windows it looks like alarm has an extra delay
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446 | * (maybe related to creating a new thread). Allow some room here. */
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447 | if( millisecs < 800 * secs || millisecs > 1200 * secs + 300 )
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448 | FAIL;
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449 | }
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450 |
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451 | if( verbose != 0 )
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452 | mbedtls_printf( "passed\n" );
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453 |
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454 | if( verbose != 0 )
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455 | mbedtls_printf( " TIMING test #2 (set/get_delay ): " );
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456 |
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457 | {
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458 | a = 800;
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459 | b = 400;
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460 | mbedtls_timing_set_delay( &ctx, a, a + b ); /* T = 0 */
|
---|
461 |
|
---|
462 | busy_msleep( a - a / 4 ); /* T = a - a/4 */
|
---|
463 | if( mbedtls_timing_get_delay( &ctx ) != 0 )
|
---|
464 | FAIL;
|
---|
465 |
|
---|
466 | busy_msleep( a / 4 + b / 4 ); /* T = a + b/4 */
|
---|
467 | if( mbedtls_timing_get_delay( &ctx ) != 1 )
|
---|
468 | FAIL;
|
---|
469 |
|
---|
470 | busy_msleep( b ); /* T = a + b + b/4 */
|
---|
471 | if( mbedtls_timing_get_delay( &ctx ) != 2 )
|
---|
472 | FAIL;
|
---|
473 | }
|
---|
474 |
|
---|
475 | mbedtls_timing_set_delay( &ctx, 0, 0 );
|
---|
476 | busy_msleep( 200 );
|
---|
477 | if( mbedtls_timing_get_delay( &ctx ) != -1 )
|
---|
478 | FAIL;
|
---|
479 |
|
---|
480 | if( verbose != 0 )
|
---|
481 | mbedtls_printf( "passed\n" );
|
---|
482 |
|
---|
483 | if( verbose != 0 )
|
---|
484 | mbedtls_printf( " TIMING test #3 (hardclock / get_timer): " );
|
---|
485 |
|
---|
486 | /*
|
---|
487 | * Allow one failure for possible counter wrapping.
|
---|
488 | * On a 4Ghz 32-bit machine the cycle counter wraps about once per second;
|
---|
489 | * since the whole test is about 10ms, it shouldn't happen twice in a row.
|
---|
490 | */
|
---|
491 |
|
---|
492 | hard_test:
|
---|
493 | if( hardfail > 1 )
|
---|
494 | {
|
---|
495 | if( verbose != 0 )
|
---|
496 | mbedtls_printf( "failed (ignored)\n" );
|
---|
497 |
|
---|
498 | goto hard_test_done;
|
---|
499 | }
|
---|
500 |
|
---|
501 | /* Get a reference ratio cycles/ms */
|
---|
502 | millisecs = 1;
|
---|
503 | cycles = mbedtls_timing_hardclock();
|
---|
504 | busy_msleep( millisecs );
|
---|
505 | cycles = mbedtls_timing_hardclock() - cycles;
|
---|
506 | ratio = cycles / millisecs;
|
---|
507 |
|
---|
508 | /* Check that the ratio is mostly constant */
|
---|
509 | for( millisecs = 2; millisecs <= 4; millisecs++ )
|
---|
510 | {
|
---|
511 | cycles = mbedtls_timing_hardclock();
|
---|
512 | busy_msleep( millisecs );
|
---|
513 | cycles = mbedtls_timing_hardclock() - cycles;
|
---|
514 |
|
---|
515 | /* Allow variation up to 20% */
|
---|
516 | if( cycles / millisecs < ratio - ratio / 5 ||
|
---|
517 | cycles / millisecs > ratio + ratio / 5 )
|
---|
518 | {
|
---|
519 | hardfail++;
|
---|
520 | goto hard_test;
|
---|
521 | }
|
---|
522 | }
|
---|
523 |
|
---|
524 | if( verbose != 0 )
|
---|
525 | mbedtls_printf( "passed\n" );
|
---|
526 |
|
---|
527 | hard_test_done:
|
---|
528 |
|
---|
529 | if( verbose != 0 )
|
---|
530 | mbedtls_printf( "\n" );
|
---|
531 |
|
---|
532 | return( 0 );
|
---|
533 | }
|
---|
534 |
|
---|
535 | #endif /* MBEDTLS_SELF_TEST */
|
---|
536 |
|
---|
537 | #endif /* MBEDTLS_TIMING_C */
|
---|