path: root/security/apparmor/include/lib.h

/*
 * AppArmor security module
 *
 * This file contains AppArmor lib definitions
 *
 * 2017 Canonical Ltd.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation, version 2 of the
 * License.
 */

#ifndef __AA_LIB_H
#define __AA_LIB_H

#include <linux/slab.h>
#include <linux/fs.h>

#include "match.h"

/*
 * DEBUG remains global (no per profile flag) since it is mostly used in sysctl
 * which is not related to profile accesses.
 */

#define AA_DEBUG(fmt, args...)						\
	do {								\
		if (aa_g_debug)						\
			pr_debug_ratelimited("AppArmor: " fmt, ##args);	\
	} while (0)

#define AA_ERROR(fmt, args...)						\
	pr_err_ratelimited("AppArmor: " fmt, ##args)

/* Flag indicating whether initialization completed */
extern int apparmor_initialized __initdata;

/* fn's in lib */
char *aa_split_fqname(char *args, char **ns_name);
void aa_info_message(const char *str);
void *__aa_kvmalloc(size_t size, gfp_t flags);

static inline void *kvmalloc(size_t size)
{
	return __aa_kvmalloc(size, 0);
}

static inline void *kvzalloc(size_t size)
{
	return __aa_kvmalloc(size, __GFP_ZERO);
}

/* returns 0 if kref not incremented */
static inline int kref_get_not0(struct kref *kref)
{
	return atomic_inc_not_zero(&kref->refcount);
}

/**
 * aa_strneq - compare null terminated @str to a non null terminated substring
 * @str: a null terminated string
 * @sub: a substring, not necessarily null terminated
 * @len: length of @sub to compare
 *
 * The @str string must be full consumed for this to be considered a match
 */
static inline bool aa_strneq(const char *str, const char *sub, int len)
{
	return !strncmp(str, sub, len) && !str[len];
}

/**
 * aa_dfa_null_transition - step to next state after null character
 * @dfa: the dfa to match against
 * @start: the state of the dfa to start matching in
 *
 * aa_dfa_null_transition transitions to the next state after a null
 * character which is not used in standard matching and is only
 * used to separate pairs.
 */
static inline unsigned int aa_dfa_null_transition(struct aa_dfa *dfa,
						  unsigned int start)
{
	/* the null transition only needs the string's null terminator byte */
	return aa_dfa_next(dfa, start, 0);
}

static inline bool mediated_filesystem(struct dentry *dentry)
{
	return !(dentry->d_sb->s_flags & MS_NOUSER);
}

#endif /* AA_LIB_H */