cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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vdso_test_gettimeofday.c (1594B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * vdso_test_gettimeofday.c: Sample code to test parse_vdso.c and
      4 *                           vDSO gettimeofday()
      5 * Copyright (c) 2014 Andy Lutomirski
      6 *
      7 * Compile with:
      8 * gcc -std=gnu99 vdso_test_gettimeofday.c parse_vdso_gettimeofday.c
      9 *
     10 * Tested on x86, 32-bit and 64-bit.  It may work on other architectures, too.
     11 */
     12
     13#include <stdint.h>
     14#include <elf.h>
     15#include <stdio.h>
     16#include <sys/auxv.h>
     17#include <sys/time.h>
     18
     19#include "../kselftest.h"
     20#include "parse_vdso.h"
     21
     22/*
     23 * ARM64's vDSO exports its gettimeofday() implementation with a different
     24 * name and version from other architectures, so we need to handle it as
     25 * a special case.
     26 */
     27#if defined(__aarch64__)
     28const char *version = "LINUX_2.6.39";
     29const char *name = "__kernel_gettimeofday";
     30#else
     31const char *version = "LINUX_2.6";
     32const char *name = "__vdso_gettimeofday";
     33#endif
     34
     35int main(int argc, char **argv)
     36{
     37	unsigned long sysinfo_ehdr = getauxval(AT_SYSINFO_EHDR);
     38	if (!sysinfo_ehdr) {
     39		printf("AT_SYSINFO_EHDR is not present!\n");
     40		return KSFT_SKIP;
     41	}
     42
     43	vdso_init_from_sysinfo_ehdr(getauxval(AT_SYSINFO_EHDR));
     44
     45	/* Find gettimeofday. */
     46	typedef long (*gtod_t)(struct timeval *tv, struct timezone *tz);
     47	gtod_t gtod = (gtod_t)vdso_sym(version, name);
     48
     49	if (!gtod) {
     50		printf("Could not find %s\n", name);
     51		return KSFT_SKIP;
     52	}
     53
     54	struct timeval tv;
     55	long ret = gtod(&tv, 0);
     56
     57	if (ret == 0) {
     58		printf("The time is %lld.%06lld\n",
     59		       (long long)tv.tv_sec, (long long)tv.tv_usec);
     60	} else {
     61		printf("%s failed\n", name);
     62		return KSFT_FAIL;
     63	}
     64
     65	return 0;
     66}