1 /*
2 * Portable interface to the CPU cycle counter
3 *
4 * Copyright The Mbed TLS Contributors
5 * SPDX-License-Identifier: Apache-2.0
6 *
7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
8 * not use this file except in compliance with the License.
9 * You may obtain a copy of the License at
10 *
11 * http://www.apache.org/licenses/LICENSE-2.0
12 *
13 * Unless required by applicable law or agreed to in writing, software
14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16 * See the License for the specific language governing permissions and
17 * limitations under the License.
18 */
19
20 #include "common.h"
21
22 #if defined(MBEDTLS_TIMING_C)
23
24 #include "mbedtls/timing.h"
25
26 #if !defined(MBEDTLS_TIMING_ALT)
27
28 #if !defined(unix) && !defined(__unix__) && !defined(__unix) && \
29 !defined(__APPLE__) && !defined(_WIN32) && !defined(__QNXNTO__) && \
30 !defined(__HAIKU__) && !defined(__midipix__)
31 #error "This module only works on Unix and Windows, see MBEDTLS_TIMING_C in mbedtls_config.h"
32 #endif
33
34 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
35
36 #include <windows.h>
37 #include <process.h>
38
39 struct _hr_time
40 {
41 LARGE_INTEGER start;
42 };
43
44 #else
45
46 #include <unistd.h>
47 #include <sys/types.h>
48 #include <signal.h>
49 /* time.h should be included independently of MBEDTLS_HAVE_TIME. If the
50 * platform matches the ifdefs above, it will be used. */
51 #include <time.h>
52 #include <sys/time.h>
53 struct _hr_time
54 {
55 struct timeval start;
56 };
57 #endif /* _WIN32 && !EFIX64 && !EFI32 */
58
59 /**
60 * \brief Return the elapsed time in milliseconds
61 *
62 * \warning May change without notice
63 *
64 * \param val points to a timer structure
65 * \param reset If 0, query the elapsed time. Otherwise (re)start the timer.
66 *
67 * \return Elapsed time since the previous reset in ms. When
68 * restarting, this is always 0.
69 *
70 * \note To initialize a timer, call this function with reset=1.
71 *
72 * Determining the elapsed time and resetting the timer is not
73 * atomic on all platforms, so after the sequence
74 * `{ get_timer(1); ...; time1 = get_timer(1); ...; time2 =
75 * get_timer(0) }` the value time1+time2 is only approximately
76 * the delay since the first reset.
77 */
78 #if defined(_WIN32) && !defined(EFIX64) && !defined(EFI32)
79
mbedtls_timing_get_timer(struct mbedtls_timing_hr_time * val,int reset)80 unsigned long mbedtls_timing_get_timer( struct mbedtls_timing_hr_time *val, int reset )
81 {
82 struct _hr_time *t = (struct _hr_time *) val;
83
84 if( reset )
85 {
86 QueryPerformanceCounter( &t->start );
87 return( 0 );
88 }
89 else
90 {
91 unsigned long delta;
92 LARGE_INTEGER now, hfreq;
93 QueryPerformanceCounter( &now );
94 QueryPerformanceFrequency( &hfreq );
95 delta = (unsigned long)( ( now.QuadPart - t->start.QuadPart ) * 1000ul
96 / hfreq.QuadPart );
97 return( delta );
98 }
99 }
100
101 #else /* _WIN32 && !EFIX64 && !EFI32 */
102
mbedtls_timing_get_timer(struct mbedtls_timing_hr_time * val,int reset)103 unsigned long mbedtls_timing_get_timer( struct mbedtls_timing_hr_time *val, int reset )
104 {
105 struct _hr_time *t = (struct _hr_time *) val;
106
107 if( reset )
108 {
109 gettimeofday( &t->start, NULL );
110 return( 0 );
111 }
112 else
113 {
114 unsigned long delta;
115 struct timeval now;
116 gettimeofday( &now, NULL );
117 delta = ( now.tv_sec - t->start.tv_sec ) * 1000ul
118 + ( now.tv_usec - t->start.tv_usec ) / 1000;
119 return( delta );
120 }
121 }
122
123 #endif /* _WIN32 && !EFIX64 && !EFI32 */
124
125 /*
126 * Set delays to watch
127 */
mbedtls_timing_set_delay(void * data,uint32_t int_ms,uint32_t fin_ms)128 void mbedtls_timing_set_delay( void *data, uint32_t int_ms, uint32_t fin_ms )
129 {
130 mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data;
131
132 ctx->int_ms = int_ms;
133 ctx->fin_ms = fin_ms;
134
135 if( fin_ms != 0 )
136 (void) mbedtls_timing_get_timer( &ctx->timer, 1 );
137 }
138
139 /*
140 * Get number of delays expired
141 */
mbedtls_timing_get_delay(void * data)142 int mbedtls_timing_get_delay( void *data )
143 {
144 mbedtls_timing_delay_context *ctx = (mbedtls_timing_delay_context *) data;
145 unsigned long elapsed_ms;
146
147 if( ctx->fin_ms == 0 )
148 return( -1 );
149
150 elapsed_ms = mbedtls_timing_get_timer( &ctx->timer, 0 );
151
152 if( elapsed_ms >= ctx->fin_ms )
153 return( 2 );
154
155 if( elapsed_ms >= ctx->int_ms )
156 return( 1 );
157
158 return( 0 );
159 }
160
161 /*
162 * Get the final delay.
163 */
mbedtls_timing_get_final_delay(const mbedtls_timing_delay_context * data)164 uint32_t mbedtls_timing_get_final_delay(
165 const mbedtls_timing_delay_context *data )
166 {
167 return( data->fin_ms );
168 }
169 #endif /* !MBEDTLS_TIMING_ALT */
170 #endif /* MBEDTLS_TIMING_C */
171
