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/*	$NetBSD: t_ifunc.c,v 1.9 2019/07/09 16:24:01 maya Exp $	*/

/*
 * Copyright (c) 2014 The NetBSD Foundation, Inc.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND
 * CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
 * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/types.h>

#include <atf-c.h>
#include <dlfcn.h>
#include <util.h>

#include "h_macros.h"

#if defined( __arm__) || defined(__i386__) || defined(__x86_64__) || defined(__powerpc__) || defined(__sparc__)
#define	LINKER_SUPPORT 1
#else
#define	LINKER_SUPPORT 0
#endif

ATF_TC(rtld_ifunc);

ATF_TC_HEAD(rtld_ifunc, tc)
{
	atf_tc_set_md_var(tc, "descr", "ifunc functions are resolved");
}

ATF_TC_BODY(rtld_ifunc, tc)
{
	const char *envstr[] = {
	    "0", "1"
	};
	long long expected_result[] = {
	    0xdeadbeefll, 0xbeefdeadll
	};
	void *handle;
	long long (*sym)(void);
	long long result;
	const char *error;
	size_t i;

	if (!LINKER_SUPPORT)
		atf_tc_skip("Missing linker support for ifunc relocations");

	for (i = 0; i < __arraycount(envstr); ++i) {
		setenv("USE_IFUNC2", envstr[i], 1);

		handle = dlopen("libh_helper_ifunc_dso.so", RTLD_LAZY);
		error = dlerror();
		ATF_CHECK(error == NULL);
		ATF_CHECK(handle != NULL);

		sym = dlsym(handle, "ifunc");
		error = dlerror();
		ATF_CHECK(error == NULL);
		ATF_CHECK(sym != NULL);

		result = (*sym)();
		ATF_CHECK(result == expected_result[i]);

		dlclose(handle);
		error = dlerror();
		ATF_CHECK(error == NULL);

		char *command;
		easprintf(&command, "%s/h_ifunc %lld",
		    atf_tc_get_config_var(tc, "srcdir"), expected_result[i]);
		if (system(command) != EXIT_SUCCESS)
			atf_tc_fail("Test failed; see output for details");
		free(command);
	}
}

ATF_TC(rtld_hidden_ifunc);

ATF_TC_HEAD(rtld_hidden_ifunc, tc)
{
	atf_tc_set_md_var(tc, "descr", "hidden ifunc functions are resolved");
}

ATF_TC_BODY(rtld_hidden_ifunc, tc)
{
	const char *envstr[] = {
	    "0", "1"
	};
	long long expected_result[] = {
	    0xdeadbeefll, 0xbeefdeadll
	};
	void *handle;
	long long (*sym)(void);
	long long (*(*sym2)(void))(void);
	long long result;
	const char *error;
	size_t i;

	if (!LINKER_SUPPORT)
		atf_tc_skip("Missing linker support for ifunc relocations");

	for (i = 0; i < __arraycount(envstr); ++i) {
		setenv("USE_IFUNC2", envstr[i], 1);

		handle = dlopen("libh_helper_ifunc_dso.so", RTLD_LAZY);
		error = dlerror();
		ATF_CHECK(error == NULL);
		ATF_CHECK(handle != NULL);

		sym = dlsym(handle, "ifunc_plt");
		error = dlerror();
		ATF_CHECK(error == NULL);
		ATF_CHECK(sym != NULL);

		result = (*sym)();
		ATF_CHECK(result == expected_result[!i]);

		sym2 = dlsym(handle, "ifunc_indirect");
		error = dlerror();
		ATF_CHECK(error == NULL);
		ATF_CHECK(sym2 != NULL);

		sym = (*sym2)();
		result = (*sym)();
		ATF_CHECK(result == expected_result[!i]);

		dlclose(handle);
		error = dlerror();
		ATF_CHECK(error == NULL);

		char *command;
		easprintf(&command, "%s/h_ifunc %lld",
		    atf_tc_get_config_var(tc, "srcdir"), expected_result[i]);
		if (system(command) != EXIT_SUCCESS)
			atf_tc_fail("Test failed; see output for details");
		free(command);
	}
}

ATF_TC(rtld_main_ifunc);
ATF_TC_HEAD(rtld_main_ifunc, tc)
{
	atf_tc_set_md_var(tc, "descr",
	    "ifunc functions are resolved in the executable");
}

#if LINKER_SUPPORT
static long long
ifunc_helper(void)
{
	return 0xdeadbeefll;
}

static __attribute__((used))
long long (*resolve_ifunc(void))(void)
{
	return ifunc_helper;
}
__hidden_ifunc(ifunc, resolve_ifunc);
#endif
long long ifunc(void);

ATF_TC_BODY(rtld_main_ifunc, tc)
{
	if (!LINKER_SUPPORT)
		atf_tc_skip("Missing linker support for ifunc relocations");
	ATF_CHECK(ifunc() == 0xdeadbeefll);
}

ATF_TP_ADD_TCS(tp)
{
	ATF_TP_ADD_TC(tp, rtld_ifunc);
	ATF_TP_ADD_TC(tp, rtld_hidden_ifunc);
	ATF_TP_ADD_TC(tp, rtld_main_ifunc);
	return atf_no_error();
}