1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * AppArmor security module 4 * 5 * This file contains AppArmor basic path manipulation function definitions. 6 * 7 * Copyright (C) 1998-2008 Novell/SUSE 8 * Copyright 2009-2010 Canonical Ltd. 9 */ 10 11 #ifndef __AA_PATH_H 12 #define __AA_PATH_H 13 14 15 enum path_flags { 16 PATH_IS_DIR = 0x1, /* path is a directory */ 17 PATH_CONNECT_PATH = 0x4, /* connect disconnected paths to / */ 18 PATH_CHROOT_REL = 0x8, /* do path lookup relative to chroot */ 19 PATH_CHROOT_NSCONNECT = 0x10, /* connect paths that are at ns root */ 20 21 PATH_DELEGATE_DELETED = 0x08000, /* delegate deleted files */ 22 PATH_MEDIATE_DELETED = 0x10000, /* mediate deleted paths */ 23 }; 24 25 int aa_path_name(const struct path *path, int flags, char *buffer, 26 const char **name, const char **info, 27 const char *disconnected); 28 29 #define MAX_PATH_BUFFERS 2 30 31 /* Per cpu buffers used during mediation */ 32 /* preallocated buffers to use during path lookups */ 33 struct aa_buffers { 34 char *buf[MAX_PATH_BUFFERS]; 35 }; 36 37 #include <linux/percpu.h> 38 #include <linux/preempt.h> 39 40 DECLARE_PER_CPU(struct aa_buffers, aa_buffers); 41 42 #define ASSIGN(FN, A, X, N) ((X) = FN(A, N)) 43 #define EVAL1(FN, A, X) ASSIGN(FN, A, X, 0) /*X = FN(0)*/ 44 #define EVAL2(FN, A, X, Y...) \ 45 do { ASSIGN(FN, A, X, 1); EVAL1(FN, A, Y); } while (0) 46 #define EVAL(FN, A, X...) CONCATENATE(EVAL, COUNT_ARGS(X))(FN, A, X) 47 48 #define for_each_cpu_buffer(I) for ((I) = 0; (I) < MAX_PATH_BUFFERS; (I)++) 49 50 #ifdef CONFIG_DEBUG_PREEMPT 51 #define AA_BUG_PREEMPT_ENABLED(X) AA_BUG(preempt_count() <= 0, X) 52 #else 53 #define AA_BUG_PREEMPT_ENABLED(X) /* nop */ 54 #endif 55 56 #define __get_buffer(C, N) ({ \ 57 AA_BUG_PREEMPT_ENABLED("__get_buffer without preempt disabled"); \ 58 (C)->buf[(N)]; }) 59 60 #define __get_buffers(C, X...) EVAL(__get_buffer, C, X) 61 62 #define __put_buffers(X, Y...) ((void)&(X)) 63 64 #define get_buffers(X...) \ 65 do { \ 66 struct aa_buffers *__cpu_var = get_cpu_ptr(&aa_buffers); \ 67 __get_buffers(__cpu_var, X); \ 68 } while (0) 69 70 #define put_buffers(X, Y...) \ 71 do { \ 72 __put_buffers(X, Y); \ 73 put_cpu_ptr(&aa_buffers); \ 74 } while (0) 75 76 #endif /* __AA_PATH_H */ 77