diff options
Diffstat (limited to 'library/timing.c')
-rw-r--r-- | library/timing.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/library/timing.c b/library/timing.c new file mode 100644 index 00000000000..58f1c1ec2eb --- /dev/null +++ b/library/timing.c @@ -0,0 +1,154 @@ +/* + * Portable interface to the CPU cycle counter + * + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#include "common.h" + +#if defined(MBEDTLS_TIMING_C) + +#include "mbedtls/timing.h" + +#if !defined(MBEDTLS_TIMING_ALT) + +#if !defined(unix) && !defined(__unix__) && !defined(__unix) && \ + !defined(__APPLE__) && !defined(_WIN32) && !defined(__QNXNTO__) && \ + !defined(__HAIKU__) && !defined(__midipix__) +#error "This module only works on Unix and Windows, see MBEDTLS_TIMING_C in mbedtls_config.h" +#endif + +#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) + +#include <windows.h> +#include <process.h> + +struct _hr_time { + LARGE_INTEGER start; +}; + +#else + +#include <unistd.h> +#include <sys/types.h> +#include <signal.h> +/* time.h should be included independently of MBEDTLS_HAVE_TIME. If the + * platform matches the ifdefs above, it will be used. */ +#include <time.h> +#include <sys/time.h> +struct _hr_time { + struct timeval start; +}; +#endif /* _WIN32 && !EFIX64 && !EFI32 */ + +/** + * \brief Return the elapsed time in milliseconds + * + * \warning May change without notice + * + * \param val points to a timer structure + * \param reset If 0, query the elapsed time. Otherwise (re)start the timer. + * + * \return Elapsed time since the previous reset in ms. When + * restarting, this is always 0. + * + * \note To initialize a timer, call this function with reset=1. + * + * Determining the elapsed time and resetting the timer is not + * atomic on all platforms, so after the sequence + * `{ get_timer(1); ...; time1 = get_timer(1); ...; time2 = + * get_timer(0) }` the value time1+time2 is only approximately + * the delay since the first reset. + */ +#if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32) + +unsigned long mbedtls_timing_get_timer(struct mbedtls_timing_hr_time *val, int reset) +{ + struct _hr_time *t = (struct _hr_time *) val; + + if (reset) { + QueryPerformanceCounter(&t->start); + return 0; + } else { + unsigned long delta; + LARGE_INTEGER now, hfreq; + QueryPerformanceCounter(&now); + QueryPerformanceFrequency(&hfreq); + delta = (unsigned long) ((now.QuadPart - t->start.QuadPart) * 1000ul + / hfreq.QuadPart); + return delta; + } +} + +#else /* _WIN32 && !EFIX64 && !EFI32 */ + +unsigned long mbedtls_timing_get_timer(struct mbedtls_timing_hr_time *val, int reset) +{ + struct _hr_time *t = (struct _hr_time *) val; + + if (reset) { + gettimeofday(&t->start, NULL); + return 0; + } else { + unsigned long delta; + struct timeval now; + gettimeofday(&now, NULL); + delta = (now.tv_sec - t->start.tv_sec) * 1000ul + + (now.tv_usec - t->start.tv_usec) / 1000; + return delta; + } +} + +#endif /* _WIN32 && !EFIX64 && !EFI32 */ + +/* + * Set delays to watch + */ +void mbedtls_timing_set_delay(void *data, uint32_t int_ms, uint32_t fin_ms) +{ + mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data; + + ctx->int_ms = int_ms; + ctx->fin_ms = fin_ms; + + if (fin_ms != 0) { + (void) mbedtls_timing_get_timer(&ctx->timer, 1); + } +} + +/* + * Get number of delays expired + */ +int mbedtls_timing_get_delay(void *data) +{ + mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data; + unsigned long elapsed_ms; + + if (ctx->fin_ms == 0) { + return -1; + } + + elapsed_ms = mbedtls_timing_get_timer(&ctx->timer, 0); + + if (elapsed_ms >= ctx->fin_ms) { + return 2; + } + + if (elapsed_ms >= ctx->int_ms) { + return 1; + } + + return 0; +} + +/* + * Get the final delay. + */ +uint32_t mbedtls_timing_get_final_delay( + const mbedtls_timing_delay_context *data) +{ + return data->fin_ms; +} +#endif /* !MBEDTLS_TIMING_ALT */ +#endif /* MBEDTLS_TIMING_C */ |