picnoir/Systemd
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity
Systemd/src/test/test-fs-util.c
Lennart Poettering 9e3fa6e827 fs-util: rework touch_file() so that it can touch socket file nodes 
Let's rework touch_file() so that it works correctly on sockets, fifos,
and device nodes: let's open an O_PATH file descriptor first and operate
based on that, if we can. This is usually the better option as it this
means we can open AF_UNIX nodes in the file system, and update their
timestamps and ownership correctly. It also means we can correctly touch
symlinks and block/character devices without triggering their drivers.

Moreover, by operating on an O_PATH fd we can make sure that we
operate on the same inode the whole time, and it can't be swapped out in
the middle.

While we are at it, rework the call so that we try to adjust as much as
we can before returning on error. This is a good idea as we call the
function quite often without checking its result, and hence it's best to
leave the files around in the most "correct" fashion possible.
2018-01-05 13:55:08 +01:00

489 lines
16 KiB
C
Raw Blame History

/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
Copyright 2010 Lennart Poettering
systemd is free software; you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version.
systemd is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/
#include <unistd.h>
#include "alloc-util.h"
#include "fd-util.h"
#include "fileio.h"
#include "fs-util.h"
#include "macro.h"
#include "mkdir.h"
#include "path-util.h"
#include "rm-rf.h"
#include "string-util.h"
#include "strv.h"
#include "util.h"
static void test_chase_symlinks(void) {
_cleanup_free_ char *result = NULL;
char temp[] = "/tmp/test-chase.XXXXXX";
const char *top, *p, *pslash, *q, *qslash;
int r;
assert_se(mkdtemp(temp));
top = strjoina(temp, "/top");
assert_se(mkdir(top, 0700) >= 0);
p = strjoina(top, "/dot");
assert_se(symlink(".", p) >= 0);
p = strjoina(top, "/dotdot");
assert_se(symlink("..", p) >= 0);
p = strjoina(top, "/dotdota");
assert_se(symlink("../a", p) >= 0);
p = strjoina(temp, "/a");
assert_se(symlink("b", p) >= 0);
p = strjoina(temp, "/b");
assert_se(symlink("/usr", p) >= 0);
p = strjoina(temp, "/start");
assert_se(symlink("top/dot/dotdota", p) >= 0);
/* Paths that use symlinks underneath the "root" */
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, "/usr"));
result = mfree(result);
pslash = strjoina(p, "/");
r = chase_symlinks(pslash, NULL, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, "/usr/"));
result = mfree(result);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r == -ENOENT);
r = chase_symlinks(pslash, temp, 0, &result);
assert_se(r == -ENOENT);
q = strjoina(temp, "/usr");
r = chase_symlinks(p, temp, CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(path_equal(result, q));
result = mfree(result);
qslash = strjoina(q, "/");
r = chase_symlinks(pslash, temp, CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(path_equal(result, qslash));
result = mfree(result);
assert_se(mkdir(q, 0700) >= 0);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, q));
result = mfree(result);
r = chase_symlinks(pslash, temp, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, qslash));
result = mfree(result);
p = strjoina(temp, "/slash");
assert_se(symlink("/", p) >= 0);
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, "/"));
result = mfree(result);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, temp));
result = mfree(result);
/* Paths that would "escape" outside of the "root" */
p = strjoina(temp, "/6dots");
assert_se(symlink("../../..", p) >= 0);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0 && path_equal(result, temp));
result = mfree(result);
p = strjoina(temp, "/6dotsusr");
assert_se(symlink("../../../usr", p) >= 0);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0 && path_equal(result, q));
result = mfree(result);
p = strjoina(temp, "/top/8dotsusr");
assert_se(symlink("../../../../usr", p) >= 0);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0 && path_equal(result, q));
result = mfree(result);
/* Paths that contain repeated slashes */
p = strjoina(temp, "/slashslash");
assert_se(symlink("///usr///", p) >= 0);
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, "/usr"));
result = mfree(result);
r = chase_symlinks(p, temp, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, q));
result = mfree(result);
/* Paths using . */
r = chase_symlinks("/etc/./.././", NULL, 0, &result);
assert_se(r > 0);
assert_se(path_equal(result, "/"));
result = mfree(result);
r = chase_symlinks("/etc/./.././", "/etc", 0, &result);
assert_se(r > 0 && path_equal(result, "/etc"));
result = mfree(result);
r = chase_symlinks("/../.././//../../etc", NULL, 0, &result);
assert_se(r > 0);
assert_se(streq(result, "/etc"));
result = mfree(result);
r = chase_symlinks("/../.././//../../test-chase.fsldajfl", NULL, CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(streq(result, "/test-chase.fsldajfl"));
result = mfree(result);
r = chase_symlinks("/../.././//../../etc", "/", CHASE_PREFIX_ROOT, &result);
assert_se(r > 0);
assert_se(streq(result, "/etc"));
result = mfree(result);
r = chase_symlinks("/../.././//../../test-chase.fsldajfl", "/", CHASE_PREFIX_ROOT|CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(streq(result, "/test-chase.fsldajfl"));
result = mfree(result);
r = chase_symlinks("/etc/machine-id/foo", NULL, 0, &result);
assert_se(r == -ENOTDIR);
result = mfree(result);
/* Path that loops back to self */
p = strjoina(temp, "/recursive-symlink");
assert_se(symlink("recursive-symlink", p) >= 0);
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r == -ELOOP);
/* Path which doesn't exist */
p = strjoina(temp, "/idontexist");
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r == -ENOENT);
r = chase_symlinks(p, NULL, CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(path_equal(result, p));
result = mfree(result);
p = strjoina(temp, "/idontexist/meneither");
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r == -ENOENT);
r = chase_symlinks(p, NULL, CHASE_NONEXISTENT, &result);
assert_se(r == 0);
assert_se(path_equal(result, p));
result = mfree(result);
/* Path which doesn't exist, but contains weird stuff */
p = strjoina(temp, "/idontexist/..");
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r == -ENOENT);
r = chase_symlinks(p, NULL, CHASE_NONEXISTENT, &result);
assert_se(r == -ENOENT);
p = strjoina(temp, "/target");
q = strjoina(temp, "/top");
assert_se(symlink(q, p) >= 0);
p = strjoina(temp, "/target/idontexist");
r = chase_symlinks(p, NULL, 0, &result);
assert_se(r == -ENOENT);
assert_se(rm_rf(temp, REMOVE_ROOT|REMOVE_PHYSICAL) >= 0);
}
static void test_unlink_noerrno(void) {
char name[] = "/tmp/test-close_nointr.XXXXXX";
int fd;
fd = mkostemp_safe(name);
assert_se(fd >= 0);
assert_se(close_nointr(fd) >= 0);
{
PROTECT_ERRNO;
errno = -42;
assert_se(unlink_noerrno(name) >= 0);
assert_se(errno == -42);
assert_se(unlink_noerrno(name) < 0);
assert_se(errno == -42);
}
}
static void test_readlink_and_make_absolute(void) {
char tempdir[] = "/tmp/test-readlink_and_make_absolute";
char name[] = "/tmp/test-readlink_and_make_absolute/original";
char name2[] = "test-readlink_and_make_absolute/original";
char name_alias[] = "/tmp/test-readlink_and_make_absolute-alias";
char *r = NULL;
_cleanup_free_ char *pwd = NULL;
assert_se(mkdir_safe(tempdir, 0755, getuid(), getgid(), false) >= 0);
assert_se(touch(name) >= 0);
assert_se(symlink(name, name_alias) >= 0);
assert_se(readlink_and_make_absolute(name_alias, &r) >= 0);
assert_se(streq(r, name));
free(r);
assert_se(unlink(name_alias) >= 0);
assert_se(pwd = get_current_dir_name());
assert_se(chdir(tempdir) >= 0);
assert_se(symlink(name2, name_alias) >= 0);
assert_se(readlink_and_make_absolute(name_alias, &r) >= 0);
assert_se(streq(r, name));
free(r);
assert_se(unlink(name_alias) >= 0);
assert_se(chdir(pwd) >= 0);
assert_se(rm_rf(tempdir, REMOVE_ROOT|REMOVE_PHYSICAL) >= 0);
}
static void test_get_files_in_directory(void) {
_cleanup_strv_free_ char **l = NULL, **t = NULL;
assert_se(get_files_in_directory("/tmp", &l) >= 0);
assert_se(get_files_in_directory(".", &t) >= 0);
assert_se(get_files_in_directory(".", NULL) >= 0);
}
static void test_var_tmp(void) {
_cleanup_free_ char *tmpdir_backup = NULL, *temp_backup = NULL, *tmp_backup = NULL;
const char *tmp_dir = NULL, *t;
t = getenv("TMPDIR");
if (t) {
tmpdir_backup = strdup(t);
assert_se(tmpdir_backup);
}
t = getenv("TEMP");
if (t) {
temp_backup = strdup(t);
assert_se(temp_backup);
}
t = getenv("TMP");
if (t) {
tmp_backup = strdup(t);
assert_se(tmp_backup);
}
assert_se(unsetenv("TMPDIR") >= 0);
assert_se(unsetenv("TEMP") >= 0);
assert_se(unsetenv("TMP") >= 0);
assert_se(var_tmp_dir(&tmp_dir) >= 0);
assert_se(streq(tmp_dir, "/var/tmp"));
assert_se(setenv("TMPDIR", "/tmp", true) >= 0);
assert_se(streq(getenv("TMPDIR"), "/tmp"));
assert_se(var_tmp_dir(&tmp_dir) >= 0);
assert_se(streq(tmp_dir, "/tmp"));
assert_se(setenv("TMPDIR", "/88_does_not_exist_88", true) >= 0);
assert_se(streq(getenv("TMPDIR"), "/88_does_not_exist_88"));
assert_se(var_tmp_dir(&tmp_dir) >= 0);
assert_se(streq(tmp_dir, "/var/tmp"));
if (tmpdir_backup) {
assert_se(setenv("TMPDIR", tmpdir_backup, true) >= 0);
assert_se(streq(getenv("TMPDIR"), tmpdir_backup));
}
if (temp_backup) {
assert_se(setenv("TEMP", temp_backup, true) >= 0);
assert_se(streq(getenv("TEMP"), temp_backup));
}
if (tmp_backup) {
assert_se(setenv("TMP", tmp_backup, true) >= 0);
assert_se(streq(getenv("TMP"), tmp_backup));
}
}
static void test_dot_or_dot_dot(void) {
assert_se(!dot_or_dot_dot(NULL));
assert_se(!dot_or_dot_dot(""));
assert_se(!dot_or_dot_dot("xxx"));
assert_se(dot_or_dot_dot("."));
assert_se(dot_or_dot_dot(".."));
assert_se(!dot_or_dot_dot(".foo"));
assert_se(!dot_or_dot_dot("..foo"));
}
static void test_access_fd(void) {
_cleanup_(rmdir_and_freep) char *p = NULL;
_cleanup_close_ int fd = -1;
assert_se(mkdtemp_malloc("/tmp/access-fd.XXXXXX", &p) >= 0);
fd = open(p, O_RDONLY|O_DIRECTORY|O_CLOEXEC);
assert_se(fd >= 0);
assert_se(access_fd(fd, R_OK) >= 0);
assert_se(access_fd(fd, F_OK) >= 0);
assert_se(access_fd(fd, W_OK) >= 0);
assert_se(fchmod(fd, 0000) >= 0);
assert_se(access_fd(fd, F_OK) >= 0);
if (geteuid() == 0) {
assert_se(access_fd(fd, R_OK) >= 0);
assert_se(access_fd(fd, W_OK) >= 0);
} else {
assert_se(access_fd(fd, R_OK) == -EACCES);
assert_se(access_fd(fd, W_OK) == -EACCES);
}
}
static void test_touch_file(void) {
uid_t test_uid, test_gid;
_cleanup_(rm_rf_physical_and_freep) char *p = NULL;
struct stat st;
const char *a;
usec_t test_mtime;
test_uid = geteuid() == 0 ? 65534 : getuid();
test_gid = geteuid() == 0 ? 65534 : getgid();
test_mtime = usec_sub_unsigned(now(CLOCK_REALTIME), USEC_PER_WEEK);
assert_se(mkdtemp_malloc("/dev/shm/touch-file-XXXXXX", &p) >= 0);
a = strjoina(p, "/regular");
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISREG(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
a = strjoina(p, "/dir");
assert_se(mkdir(a, 0775) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISDIR(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
a = strjoina(p, "/fifo");
assert_se(mkfifo(a, 0775) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISFIFO(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
a = strjoina(p, "/sock");
assert_se(mknod(a, 0775 | S_IFSOCK, 0) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISSOCK(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
if (geteuid() == 0) {
a = strjoina(p, "/cdev");
assert_se(mknod(a, 0775 | S_IFCHR, makedev(0, 0)) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISCHR(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
a = strjoina(p, "/bdev");
assert_se(mknod(a, 0775 | S_IFBLK, makedev(0, 0)) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISBLK(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
}
a = strjoina(p, "/lnk");
assert_se(symlink("target", a) >= 0);
assert_se(touch_file(a, false, test_mtime, test_uid, test_gid, 0640) >= 0);
assert_se(lstat(a, &st) >= 0);
assert_se(st.st_uid == test_uid);
assert_se(st.st_gid == test_gid);
assert_se(S_ISLNK(st.st_mode));
assert_se((st.st_mode & 0777) == 0640);
assert_se(timespec_load(&st.st_mtim) == test_mtime);
}
int main(int argc, char *argv[]) {
test_unlink_noerrno();
test_get_files_in_directory();
test_readlink_and_make_absolute();
test_var_tmp();
test_chase_symlinks();
test_dot_or_dot_dot();
test_access_fd();
test_touch_file();
return 0;
}
Reference in a new issue View git blame Copy permalink