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