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
mbedtls_timing_get_timer(struct mbedtls_timing_hr_time * val,int reset)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
mbedtls_timing_get_timer(struct mbedtls_timing_hr_time * val,int reset)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 */
mbedtls_timing_set_delay(void * data,uint32_t int_ms,uint32_t fin_ms)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 */
mbedtls_timing_get_delay(void * data)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 */
mbedtls_timing_get_final_delay(const mbedtls_timing_delay_context * data)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
