1 /* 2 * Portable interface to the CPU cycle counter 3 * 4 * Copyright The Mbed TLS Contributors 5 * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later 6 */ 7 8 #include "common.h" 9 10 #if defined(MBEDTLS_TIMING_C) 11 12 #include "mbedtls/timing.h" 13 14 #if !defined(MBEDTLS_TIMING_ALT) 15 16 #if !defined(unix) && !defined(__unix__) && !defined(__unix) && \ 17 !defined(__APPLE__) && !defined(_WIN32) && !defined(__QNXNTO__) && \ 18 !defined(__HAIKU__) && !defined(__midipix__) 19 #error "This module only works on Unix and Windows, see MBEDTLS_TIMING_C in mbedtls_config.h" 20 #endif 21 22 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) 23 24 #include <windows.h> 25 #include <process.h> 26 27 struct _hr_time { 28 LARGE_INTEGER start; 29 }; 30 31 #else 32 33 #include <unistd.h> 34 #include <sys/types.h> 35 #include <signal.h> 36 /* time.h should be included independently of MBEDTLS_HAVE_TIME. If the 37 * platform matches the ifdefs above, it will be used. */ 38 #include <time.h> 39 #include <sys/time.h> 40 struct _hr_time { 41 struct timeval start; 42 }; 43 #endif /* _WIN32 && !EFIX64 && !EFI32 */ 44 45 /** 46 * \brief Return the elapsed time in milliseconds 47 * 48 * \warning May change without notice 49 * 50 * \param val points to a timer structure 51 * \param reset If 0, query the elapsed time. Otherwise (re)start the timer. 52 * 53 * \return Elapsed time since the previous reset in ms. When 54 * restarting, this is always 0. 55 * 56 * \note To initialize a timer, call this function with reset=1. 57 * 58 * Determining the elapsed time and resetting the timer is not 59 * atomic on all platforms, so after the sequence 60 * `{ get_timer(1); ...; time1 = get_timer(1); ...; time2 = 61 * get_timer(0) }` the value time1+time2 is only approximately 62 * the delay since the first reset. 63 */ 64 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) 65 66 unsigned long mbedtls_timing_get_timer(struct mbedtls_timing_hr_time *val, int reset) 67 { 68 struct _hr_time *t = (struct _hr_time *) val; 69 70 if (reset) { 71 QueryPerformanceCounter(&t->start); 72 return 0; 73 } else { 74 unsigned long delta; 75 LARGE_INTEGER now, hfreq; 76 QueryPerformanceCounter(&now); 77 QueryPerformanceFrequency(&hfreq); 78 delta = (unsigned long) ((now.QuadPart - t->start.QuadPart) * 1000ul 79 / hfreq.QuadPart); 80 return delta; 81 } 82 } 83 84 #else /* _WIN32 && !EFIX64 && !EFI32 */ 85 86 unsigned long mbedtls_timing_get_timer(struct mbedtls_timing_hr_time *val, int reset) 87 { 88 struct _hr_time *t = (struct _hr_time *) val; 89 90 if (reset) { 91 gettimeofday(&t->start, NULL); 92 return 0; 93 } else { 94 unsigned long delta; 95 struct timeval now; 96 gettimeofday(&now, NULL); 97 delta = (now.tv_sec - t->start.tv_sec) * 1000ul 98 + (now.tv_usec - t->start.tv_usec) / 1000; 99 return delta; 100 } 101 } 102 103 #endif /* _WIN32 && !EFIX64 && !EFI32 */ 104 105 /* 106 * Set delays to watch 107 */ 108 void mbedtls_timing_set_delay(void *data, uint32_t int_ms, uint32_t fin_ms) 109 { 110 mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data; 111 112 ctx->int_ms = int_ms; 113 ctx->fin_ms = fin_ms; 114 115 if (fin_ms != 0) { 116 (void) mbedtls_timing_get_timer(&ctx->timer, 1); 117 } 118 } 119 120 /* 121 * Get number of delays expired 122 */ 123 int mbedtls_timing_get_delay(void *data) 124 { 125 mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data; 126 unsigned long elapsed_ms; 127 128 if (ctx->fin_ms == 0) { 129 return -1; 130 } 131 132 elapsed_ms = mbedtls_timing_get_timer(&ctx->timer, 0); 133 134 if (elapsed_ms >= ctx->fin_ms) { 135 return 2; 136 } 137 138 if (elapsed_ms >= ctx->int_ms) { 139 return 1; 140 } 141 142 return 0; 143 } 144 145 /* 146 * Get the final delay. 147 */ 148 uint32_t mbedtls_timing_get_final_delay( 149 const mbedtls_timing_delay_context *data) 150 { 151 return data->fin_ms; 152 } 153 #endif /* !MBEDTLS_TIMING_ALT */ 154 #endif /* MBEDTLS_TIMING_C */ 155