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