1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0-or-later 2*4882a593Smuzhiyun /* 3*4882a593Smuzhiyun * Author: Aleksa Sarai <cyphar@cyphar.com> 4*4882a593Smuzhiyun * Copyright (C) 2018-2019 SUSE LLC. 5*4882a593Smuzhiyun */ 6*4882a593Smuzhiyun 7*4882a593Smuzhiyun #ifndef __RESOLVEAT_H__ 8*4882a593Smuzhiyun #define __RESOLVEAT_H__ 9*4882a593Smuzhiyun 10*4882a593Smuzhiyun #define _GNU_SOURCE 11*4882a593Smuzhiyun #include <stdint.h> 12*4882a593Smuzhiyun #include <stdbool.h> 13*4882a593Smuzhiyun #include <errno.h> 14*4882a593Smuzhiyun #include <linux/types.h> 15*4882a593Smuzhiyun #include "../kselftest.h" 16*4882a593Smuzhiyun 17*4882a593Smuzhiyun #define ARRAY_LEN(X) (sizeof (X) / sizeof (*(X))) 18*4882a593Smuzhiyun #define BUILD_BUG_ON(e) ((void)(sizeof(struct { int:(-!!(e)); }))) 19*4882a593Smuzhiyun 20*4882a593Smuzhiyun #ifndef SYS_openat2 21*4882a593Smuzhiyun #ifndef __NR_openat2 22*4882a593Smuzhiyun #define __NR_openat2 437 23*4882a593Smuzhiyun #endif /* __NR_openat2 */ 24*4882a593Smuzhiyun #define SYS_openat2 __NR_openat2 25*4882a593Smuzhiyun #endif /* SYS_openat2 */ 26*4882a593Smuzhiyun 27*4882a593Smuzhiyun /* 28*4882a593Smuzhiyun * Arguments for how openat2(2) should open the target path. If @resolve is 29*4882a593Smuzhiyun * zero, then openat2(2) operates very similarly to openat(2). 30*4882a593Smuzhiyun * 31*4882a593Smuzhiyun * However, unlike openat(2), unknown bits in @flags result in -EINVAL rather 32*4882a593Smuzhiyun * than being silently ignored. @mode must be zero unless one of {O_CREAT, 33*4882a593Smuzhiyun * O_TMPFILE} are set. 34*4882a593Smuzhiyun * 35*4882a593Smuzhiyun * @flags: O_* flags. 36*4882a593Smuzhiyun * @mode: O_CREAT/O_TMPFILE file mode. 37*4882a593Smuzhiyun * @resolve: RESOLVE_* flags. 38*4882a593Smuzhiyun */ 39*4882a593Smuzhiyun struct open_how { 40*4882a593Smuzhiyun __u64 flags; 41*4882a593Smuzhiyun __u64 mode; 42*4882a593Smuzhiyun __u64 resolve; 43*4882a593Smuzhiyun }; 44*4882a593Smuzhiyun 45*4882a593Smuzhiyun #define OPEN_HOW_SIZE_VER0 24 /* sizeof first published struct */ 46*4882a593Smuzhiyun #define OPEN_HOW_SIZE_LATEST OPEN_HOW_SIZE_VER0 47*4882a593Smuzhiyun 48*4882a593Smuzhiyun bool needs_openat2(const struct open_how *how); 49*4882a593Smuzhiyun 50*4882a593Smuzhiyun #ifndef RESOLVE_IN_ROOT 51*4882a593Smuzhiyun /* how->resolve flags for openat2(2). */ 52*4882a593Smuzhiyun #define RESOLVE_NO_XDEV 0x01 /* Block mount-point crossings 53*4882a593Smuzhiyun (includes bind-mounts). */ 54*4882a593Smuzhiyun #define RESOLVE_NO_MAGICLINKS 0x02 /* Block traversal through procfs-style 55*4882a593Smuzhiyun "magic-links". */ 56*4882a593Smuzhiyun #define RESOLVE_NO_SYMLINKS 0x04 /* Block traversal through all symlinks 57*4882a593Smuzhiyun (implies OEXT_NO_MAGICLINKS) */ 58*4882a593Smuzhiyun #define RESOLVE_BENEATH 0x08 /* Block "lexical" trickery like 59*4882a593Smuzhiyun "..", symlinks, and absolute 60*4882a593Smuzhiyun paths which escape the dirfd. */ 61*4882a593Smuzhiyun #define RESOLVE_IN_ROOT 0x10 /* Make all jumps to "/" and ".." 62*4882a593Smuzhiyun be scoped inside the dirfd 63*4882a593Smuzhiyun (similar to chroot(2)). */ 64*4882a593Smuzhiyun #endif /* RESOLVE_IN_ROOT */ 65*4882a593Smuzhiyun 66*4882a593Smuzhiyun #define E_func(func, ...) \ 67*4882a593Smuzhiyun do { \ 68*4882a593Smuzhiyun errno = 0; \ 69*4882a593Smuzhiyun if (func(__VA_ARGS__) < 0) \ 70*4882a593Smuzhiyun ksft_exit_fail_msg("%s:%d %s failed - errno:%d\n", \ 71*4882a593Smuzhiyun __FILE__, __LINE__, #func, errno); \ 72*4882a593Smuzhiyun } while (0) 73*4882a593Smuzhiyun 74*4882a593Smuzhiyun #define E_asprintf(...) E_func(asprintf, __VA_ARGS__) 75*4882a593Smuzhiyun #define E_chmod(...) E_func(chmod, __VA_ARGS__) 76*4882a593Smuzhiyun #define E_dup2(...) E_func(dup2, __VA_ARGS__) 77*4882a593Smuzhiyun #define E_fchdir(...) E_func(fchdir, __VA_ARGS__) 78*4882a593Smuzhiyun #define E_fstatat(...) E_func(fstatat, __VA_ARGS__) 79*4882a593Smuzhiyun #define E_kill(...) E_func(kill, __VA_ARGS__) 80*4882a593Smuzhiyun #define E_mkdirat(...) E_func(mkdirat, __VA_ARGS__) 81*4882a593Smuzhiyun #define E_mount(...) E_func(mount, __VA_ARGS__) 82*4882a593Smuzhiyun #define E_prctl(...) E_func(prctl, __VA_ARGS__) 83*4882a593Smuzhiyun #define E_readlink(...) E_func(readlink, __VA_ARGS__) 84*4882a593Smuzhiyun #define E_setresuid(...) E_func(setresuid, __VA_ARGS__) 85*4882a593Smuzhiyun #define E_symlinkat(...) E_func(symlinkat, __VA_ARGS__) 86*4882a593Smuzhiyun #define E_touchat(...) E_func(touchat, __VA_ARGS__) 87*4882a593Smuzhiyun #define E_unshare(...) E_func(unshare, __VA_ARGS__) 88*4882a593Smuzhiyun 89*4882a593Smuzhiyun #define E_assert(expr, msg, ...) \ 90*4882a593Smuzhiyun do { \ 91*4882a593Smuzhiyun if (!(expr)) \ 92*4882a593Smuzhiyun ksft_exit_fail_msg("ASSERT(%s:%d) failed (%s): " msg "\n", \ 93*4882a593Smuzhiyun __FILE__, __LINE__, #expr, ##__VA_ARGS__); \ 94*4882a593Smuzhiyun } while (0) 95*4882a593Smuzhiyun 96*4882a593Smuzhiyun int raw_openat2(int dfd, const char *path, void *how, size_t size); 97*4882a593Smuzhiyun int sys_openat2(int dfd, const char *path, struct open_how *how); 98*4882a593Smuzhiyun int sys_openat(int dfd, const char *path, struct open_how *how); 99*4882a593Smuzhiyun int sys_renameat2(int olddirfd, const char *oldpath, 100*4882a593Smuzhiyun int newdirfd, const char *newpath, unsigned int flags); 101*4882a593Smuzhiyun 102*4882a593Smuzhiyun int touchat(int dfd, const char *path); 103*4882a593Smuzhiyun char *fdreadlink(int fd); 104*4882a593Smuzhiyun bool fdequal(int fd, int dfd, const char *path); 105*4882a593Smuzhiyun 106*4882a593Smuzhiyun extern bool openat2_supported; 107*4882a593Smuzhiyun 108*4882a593Smuzhiyun #endif /* __RESOLVEAT_H__ */ 109