2 * AppArmor security module
4 * This file contains AppArmor basic path manipulation function definitions.
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
20 PATH_IS_DIR = 0x1, /* path is a directory */
21 PATH_CONNECT_PATH = 0x4, /* connect disconnected paths to / */
22 PATH_CHROOT_REL = 0x8, /* do path lookup relative to chroot */
23 PATH_CHROOT_NSCONNECT = 0x10, /* connect paths that are at ns root */
25 PATH_DELEGATE_DELETED = 0x08000, /* delegate deleted files */
26 PATH_MEDIATE_DELETED = 0x10000, /* mediate deleted paths */
29 int aa_path_name(const struct path *path, int flags, char **buffer,
30 const char **name, const char **info);
32 #define MAX_PATH_BUFFERS 2
34 /* Per cpu buffers used during mediation */
35 /* preallocated buffers to use during path lookups */
37 char *buf[MAX_PATH_BUFFERS];
40 #include <linux/percpu.h>
41 #include <linux/preempt.h>
43 DECLARE_PER_CPU(struct aa_buffers, aa_buffers);
45 #define COUNT_ARGS(X...) COUNT_ARGS_HELPER(, ##X, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0)
46 #define COUNT_ARGS_HELPER(_0, _1, _2, _3, _4, _5, _6, _7, _8, _9, n, X...) n
47 #define CONCAT(X, Y) X ## Y
48 #define CONCAT_AFTER(X, Y) CONCAT(X, Y)
50 #define ASSIGN(FN, X, N) ((X) = FN(N))
51 #define EVAL1(FN, X) ASSIGN(FN, X, 0) /*X = FN(0)*/
52 #define EVAL2(FN, X, Y...) do { ASSIGN(FN, X, 1); EVAL1(FN, Y); } while (0)
53 #define EVAL(FN, X...) CONCAT_AFTER(EVAL, COUNT_ARGS(X))(FN, X)
55 #define for_each_cpu_buffer(I) for ((I) = 0; (I) < MAX_PATH_BUFFERS; (I)++)
57 #ifdef CONFIG_DEBUG_PREEMPT
58 #define AA_BUG_PREEMPT_ENABLED(X) AA_BUG(preempt_count() <= 0, X)
60 #define AA_BUG_PREEMPT_ENABLED(X) /* nop */
63 #define __get_buffer(N) ({ \
64 struct aa_buffers *__cpu_var; \
65 AA_BUG_PREEMPT_ENABLED("__get_buffer without preempt disabled"); \
66 __cpu_var = this_cpu_ptr(&aa_buffers); \
67 __cpu_var->buf[(N)]; })
69 #define __get_buffers(X...) EVAL(__get_buffer, X)
71 #define __put_buffers(X, Y...) ((void)&(X))
73 #define get_buffers(X...) \
79 #define put_buffers(X, Y...) \
81 __put_buffers(X, Y); \
85 #endif /* __AA_PATH_H */