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/*
* Copyright (c) 2020-2021, the SerenityOS developers.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/String.h>
#include <LibCore/File.h>
#include <LibTest/TestCase.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
TEST_CASE(test_change_file_contents)
{
char path[] = "/tmp/suid.XXXXXX";
auto fd = mkstemp(path);
EXPECT(fd != -1);
ftruncate(fd, 0);
EXPECT(fchmod(fd, 06755) != -1);
char buffer[8] {};
write(fd, buffer, sizeof(buffer));
struct stat s;
EXPECT(fstat(fd, &s) != -1);
close(fd);
unlink(path);
EXPECT(!(s.st_mode & S_ISUID));
EXPECT(!(s.st_mode & S_ISGID));
}
TEST_CASE(test_change_file_ownership)
{
char path[] = "/tmp/suid.XXXXXX";
auto fd = mkstemp(path);
EXPECT(fd != -1);
ftruncate(fd, 0);
EXPECT(fchmod(fd, 06755) != -1);
fchown(fd, getuid(), getgid());
struct stat s;
EXPECT(fstat(fd, &s) != -1);
close(fd);
unlink(path);
EXPECT(!(s.st_mode & S_ISUID));
EXPECT(!(s.st_mode & S_ISGID));
}
TEST_CASE(test_change_file_permissions)
{
char path[] = "/tmp/suid.XXXXXX";
auto fd = mkstemp(path);
EXPECT(fd != -1);
ftruncate(fd, 0);
EXPECT(fchmod(fd, 06755) != -1);
fchmod(fd, 0755);
struct stat s;
EXPECT(fstat(fd, &s) != -1);
close(fd);
unlink(path);
EXPECT(!(s.st_mode & S_ISUID));
EXPECT(!(s.st_mode & S_ISGID));
}
TEST_CASE(test_change_file_location)
{
char path[] = "/tmp/suid.XXXXXX";
auto fd = mkstemp(path);
EXPECT(fd != -1);
ftruncate(fd, 0);
EXPECT(fchmod(fd, 06755) != -1);
auto suid_path_or_error = Core::File::read_link(String::formatted("/proc/{}/fd/{}", getpid(), fd));
EXPECT(!suid_path_or_error.is_error());
auto suid_path = suid_path_or_error.release_value();
EXPECT(suid_path.characters());
auto new_path = String::formatted("{}.renamed", suid_path);
rename(suid_path.characters(), new_path.characters());
struct stat s;
EXPECT(lstat(new_path.characters(), &s) != -1);
close(fd);
unlink(path);
// Renamed file should retain set-uid/set-gid permissions
EXPECT(s.st_mode & S_ISUID);
EXPECT(s.st_mode & S_ISGID);
unlink(new_path.characters());
}
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