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 */ 38 struct 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 47 bool 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 94 int raw_openat2(int dfd, const char *path, void *how, size_t size); 95 int sys_openat2(int dfd, const char *path, struct open_how *how); 96 int sys_openat(int dfd, const char *path, struct open_how *how); 97 int sys_renameat2(int olddirfd, const char *oldpath, 98 int newdirfd, const char *newpath, unsigned int flags); 99 100 int touchat(int dfd, const char *path); 101 char *fdreadlink(int fd); 102 bool fdequal(int fd, int dfd, const char *path); 103 104 extern bool openat2_supported; 105 106 #endif /* __RESOLVEAT_H__ */ 107