LXR linux/tools/testing/selftests/openat2/helpers.h

   1// SPDX-License-Identifier: GPL-2.0-or-later
   2/*
   3 * Author: Aleksa Sarai <cyphar@cyphar.com>
   4 * Copyright (C) 2018-2019 SUSE LLC.
   5 */
   6
   7#ifndef __RESOLVEAT_H__
   8#define __RESOLVEAT_H__
   9
  10#define _GNU_SOURCE
  11#include <stdint.h>
  12#include <errno.h>
  13#include <linux/types.h>
  14#include "../kselftest.h"
  15
  16#define ARRAY_LEN(X) (sizeof (X) / sizeof (*(X)))
  17#define BUILD_BUG_ON(e) ((void)(sizeof(struct { int:(-!!(e)); })))
  18
  19#ifndef SYS_openat2
  20#ifndef __NR_openat2
  21#define __NR_openat2 437
  22#endif /* __NR_openat2 */
  23#define SYS_openat2 __NR_openat2
  24#endif /* SYS_openat2 */
  25
  26/*
  27 * Arguments for how openat2(2) should open the target path. If @resolve is
  28 * zero, then openat2(2) operates very similarly to openat(2).
  29 *
  30 * However, unlike openat(2), unknown bits in @flags result in -EINVAL rather
  31 * than being silently ignored. @mode must be zero unless one of {O_CREAT,
  32 * O_TMPFILE} are set.
  33 *
  34 * @flags: O_* flags.
  35 * @mode: O_CREAT/O_TMPFILE file mode.
  36 * @resolve: RESOLVE_* flags.
  37 */
  38struct open_how {
  39        __u64 flags;
  40        __u64 mode;
  41        __u64 resolve;
  42};
  43
  44#define OPEN_HOW_SIZE_VER0      24 /* sizeof first published struct */
  45#define OPEN_HOW_SIZE_LATEST    OPEN_HOW_SIZE_VER0
  46
  47bool needs_openat2(const struct open_how *how);
  48
  49#ifndef RESOLVE_IN_ROOT
  50/* how->resolve flags for openat2(2). */
  51#define RESOLVE_NO_XDEV         0x01 /* Block mount-point crossings
  52                                        (includes bind-mounts). */
  53#define RESOLVE_NO_MAGICLINKS   0x02 /* Block traversal through procfs-style
  54                                        "magic-links". */
  55#define RESOLVE_NO_SYMLINKS     0x04 /* Block traversal through all symlinks
  56                                        (implies OEXT_NO_MAGICLINKS) */
  57#define RESOLVE_BENEATH         0x08 /* Block "lexical" trickery like
  58                                        "..", symlinks, and absolute
  59                                        paths which escape the dirfd. */
  60#define RESOLVE_IN_ROOT         0x10 /* Make all jumps to "/" and ".."
  61                                        be scoped inside the dirfd
  62                                        (similar to chroot(2)). */
  63#endif /* RESOLVE_IN_ROOT */
  64
  65#define E_func(func, ...)                                               \
  66        do {                                                            \
  67                if (func(__VA_ARGS__) < 0)                              \
  68                        ksft_exit_fail_msg("%s:%d %s failed\n", \
  69                                           __FILE__, __LINE__, #func);\
  70        } while (0)
  71
  72#define E_asprintf(...)         E_func(asprintf,        __VA_ARGS__)
  73#define E_chmod(...)            E_func(chmod,           __VA_ARGS__)
  74#define E_dup2(...)             E_func(dup2,            __VA_ARGS__)
  75#define E_fchdir(...)           E_func(fchdir,          __VA_ARGS__)
  76#define E_fstatat(...)          E_func(fstatat,         __VA_ARGS__)
  77#define E_kill(...)             E_func(kill,            __VA_ARGS__)
  78#define E_mkdirat(...)          E_func(mkdirat,         __VA_ARGS__)
  79#define E_mount(...)            E_func(mount,           __VA_ARGS__)
  80#define E_prctl(...)            E_func(prctl,           __VA_ARGS__)
  81#define E_readlink(...)         E_func(readlink,        __VA_ARGS__)
  82#define E_setresuid(...)        E_func(setresuid,       __VA_ARGS__)
  83#define E_symlinkat(...)        E_func(symlinkat,       __VA_ARGS__)
  84#define E_touchat(...)          E_func(touchat,         __VA_ARGS__)
  85#define E_unshare(...)          E_func(unshare,         __VA_ARGS__)
  86
  87#define E_assert(expr, msg, ...)                                        \
  88        do {                                                            \
  89                if (!(expr))                                            \
  90                        ksft_exit_fail_msg("ASSERT(%s:%d) failed (%s): " msg "\n", \
  91                                           __FILE__, __LINE__, #expr, ##__VA_ARGS__); \
  92        } while (0)
  93
  94int raw_openat2(int dfd, const char *path, void *how, size_t size);
  95int sys_openat2(int dfd, const char *path, struct open_how *how);
  96int sys_openat(int dfd, const char *path, struct open_how *how);
  97int sys_renameat2(int olddirfd, const char *oldpath,
  98                  int newdirfd, const char *newpath, unsigned int flags);
  99
 100int touchat(int dfd, const char *path);
 101char *fdreadlink(int fd);
 102bool fdequal(int fd, int dfd, const char *path);
 103
 104extern bool openat2_supported;
 105
 106#endif /* __RESOLVEAT_H__ */
 107