file.h

  1/* SPDX-License-Identifier: GPL-2.0-only */
  2/*
  3 * AppArmor security module
  4 *
  5 * This file contains AppArmor file mediation function definitions.
  6 *
  7 * Copyright (C) 1998-2008 Novell/SUSE
  8 * Copyright 2009-2010 Canonical Ltd.
  9 */
 10
 11#ifndef __AA_FILE_H
 12#define __AA_FILE_H
 13
 14#include <linux/spinlock.h>
 15
 16#include "domain.h"
 17#include "match.h"
 18#include "perms.h"
 19
 20struct aa_policydb;
 21struct aa_profile;
 22struct path;
 23
 24#define mask_mode_t(X) (X & (MAY_EXEC | MAY_WRITE | MAY_READ | MAY_APPEND))
 25
 26#define AA_AUDIT_FILE_MASK	(MAY_READ | MAY_WRITE | MAY_EXEC | MAY_APPEND |\
 27				 AA_MAY_CREATE | AA_MAY_DELETE |	\
 28				 AA_MAY_GETATTR | AA_MAY_SETATTR | \
 29				 AA_MAY_CHMOD | AA_MAY_CHOWN | AA_MAY_LOCK | \
 30				 AA_EXEC_MMAP | AA_MAY_LINK)
 31
 32static inline struct aa_file_ctx *file_ctx(struct file *file)
 33{
 34	return file->f_security + apparmor_blob_sizes.lbs_file;
 35}
 36
 37/* struct aa_file_ctx - the AppArmor context the file was opened in
 38 * @lock: lock to update the ctx
 39 * @label: label currently cached on the ctx
 40 * @perms: the permission the file was opened with
 41 */
 42struct aa_file_ctx {
 43	spinlock_t lock;
 44	struct aa_label __rcu *label;
 45	u32 allow;
 46};
 47
 48/*
 49 * The xindex is broken into 3 parts
 50 * - index - an index into either the exec name table or the variable table
 51 * - exec type - which determines how the executable name and index are used
 52 * - flags - which modify how the destination name is applied
 53 */
 54#define AA_X_INDEX_MASK		AA_INDEX_MASK
 55
 56#define AA_X_TYPE_MASK		0x0c000000
 57#define AA_X_NONE		AA_INDEX_NONE
 58#define AA_X_NAME		0x04000000 /* use executable name px */
 59#define AA_X_TABLE		0x08000000 /* use a specified name ->n# */
 60
 61#define AA_X_UNSAFE		0x10000000
 62#define AA_X_CHILD		0x20000000
 63#define AA_X_INHERIT		0x40000000
 64#define AA_X_UNCONFINED		0x80000000
 65
 66/* need to make conditional which ones are being set */
 67struct path_cond {
 68	kuid_t uid;
 69	umode_t mode;
 70};
 71
 72#define COMBINED_PERM_MASK(X) ((X).allow | (X).audit | (X).quiet | (X).kill)
 73
 74int aa_audit_file(const struct cred *cred,
 75		  struct aa_profile *profile, struct aa_perms *perms,
 76		  const char *op, u32 request, const char *name,
 77		  const char *target, struct aa_label *tlabel, kuid_t ouid,
 78		  const char *info, int error);
 79
 80struct aa_perms *aa_lookup_condperms(kuid_t subj_uid,
 81				     struct aa_policydb *file_rules,
 82				     aa_state_t state, struct path_cond *cond);
 83aa_state_t aa_str_perms(struct aa_policydb *file_rules, aa_state_t start,
 84			const char *name, struct path_cond *cond,
 85			struct aa_perms *perms);
 86
 87int __aa_path_perm(const char *op, const struct cred *subj_cred,
 88		   struct aa_profile *profile, const char *name,
 89		   u32 request, struct path_cond *cond, int flags,
 90		   struct aa_perms *perms);
 91int aa_path_perm(const char *op, const struct cred *subj_cred,
 92		 struct aa_label *label, const struct path *path,
 93		 int flags, u32 request, struct path_cond *cond);
 94
 95int aa_path_link(const struct cred *subj_cred, struct aa_label *label,
 96		 struct dentry *old_dentry, const struct path *new_dir,
 97		 struct dentry *new_dentry);
 98
 99int aa_file_perm(const char *op, const struct cred *subj_cred,
100		 struct aa_label *label, struct file *file,
101		 u32 request, bool in_atomic);
102
103void aa_inherit_files(const struct cred *cred, struct files_struct *files);
104
105
106/**
107 * aa_map_file_to_perms - map file flags to AppArmor permissions
108 * @file: open file to map flags to AppArmor permissions
109 *
110 * Returns: apparmor permission set for the file
111 */
112static inline u32 aa_map_file_to_perms(struct file *file)
113{
114	int flags = file->f_flags;
115	u32 perms = 0;
116
117	if (file->f_mode & FMODE_WRITE)
118		perms |= MAY_WRITE;
119	if (file->f_mode & FMODE_READ)
120		perms |= MAY_READ;
121
122	if ((flags & O_APPEND) && (perms & MAY_WRITE))
123		perms = (perms & ~MAY_WRITE) | MAY_APPEND;
124	/* trunc implies write permission */
125	if (flags & O_TRUNC)
126		perms |= MAY_WRITE;
127	if (flags & O_CREAT)
128		perms |= AA_MAY_CREATE;
129
130	return perms;
131}
132
133#endif /* __AA_FILE_H */