LXR linux/security/apparmor/include/policy

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 * AppArmor security module
   4 *
   5 * This file contains AppArmor policy definitions.
   6 *
   7 * Copyright (C) 1998-2008 Novell/SUSE
   8 * Copyright 2009-2017 Canonical Ltd.
   9 */
  10
  11#ifndef __AA_NAMESPACE_H
  12#define __AA_NAMESPACE_H
  13
  14#include <linux/kref.h>
  15
  16#include "apparmor.h"
  17#include "apparmorfs.h"
  18#include "label.h"
  19#include "policy.h"
  20
  21
  22/* struct aa_ns_acct - accounting of profiles in namespace
  23 * @max_size: maximum space allowed for all profiles in namespace
  24 * @max_count: maximum number of profiles that can be in this namespace
  25 * @size: current size of profiles
  26 * @count: current count of profiles (includes null profiles)
  27 */
  28struct aa_ns_acct {
  29        int max_size;
  30        int max_count;
  31        int size;
  32        int count;
  33};
  34
  35/* struct aa_ns - namespace for a set of profiles
  36 * @base: common policy
  37 * @parent: parent of namespace
  38 * @lock: lock for modifying the object
  39 * @acct: accounting for the namespace
  40 * @unconfined: special unconfined profile for the namespace
  41 * @sub_ns: list of namespaces under the current namespace.
  42 * @uniq_null: uniq value used for null learning profiles
  43 * @uniq_id: a unique id count for the profiles in the namespace
  44 * @level: level of ns within the tree hierarchy
  45 * @dents: dentries for the namespaces file entries in apparmorfs
  46 *
  47 * An aa_ns defines the set profiles that are searched to determine which
  48 * profile to attach to a task.  Profiles can not be shared between aa_ns
  49 * and profile names within a namespace are guaranteed to be unique.  When
  50 * profiles in separate namespaces have the same name they are NOT considered
  51 * to be equivalent.
  52 *
  53 * Namespaces are hierarchical and only namespaces and profiles below the
  54 * current namespace are visible.
  55 *
  56 * Namespace names must be unique and can not contain the characters :/\0
  57 */
  58struct aa_ns {
  59        struct aa_policy base;
  60        struct aa_ns *parent;
  61        struct mutex lock;
  62        struct aa_ns_acct acct;
  63        struct aa_profile *unconfined;
  64        struct list_head sub_ns;
  65        atomic_t uniq_null;
  66        long uniq_id;
  67        int level;
  68        long revision;
  69        wait_queue_head_t wait;
  70
  71        struct aa_labelset labels;
  72        struct list_head rawdata_list;
  73
  74        struct dentry *dents[AAFS_NS_SIZEOF];
  75};
  76
  77extern struct aa_ns *root_ns;
  78
  79extern const char *aa_hidden_ns_name;
  80
  81#define ns_unconfined(NS) (&(NS)->unconfined->label)
  82
  83bool aa_ns_visible(struct aa_ns *curr, struct aa_ns *view, bool subns);
  84const char *aa_ns_name(struct aa_ns *parent, struct aa_ns *child, bool subns);
  85void aa_free_ns(struct aa_ns *ns);
  86int aa_alloc_root_ns(void);
  87void aa_free_root_ns(void);
  88void aa_free_ns_kref(struct kref *kref);
  89
  90struct aa_ns *aa_find_ns(struct aa_ns *root, const char *name);
  91struct aa_ns *aa_findn_ns(struct aa_ns *root, const char *name, size_t n);
  92struct aa_ns *__aa_lookupn_ns(struct aa_ns *view, const char *hname, size_t n);
  93struct aa_ns *aa_lookupn_ns(struct aa_ns *view, const char *name, size_t n);
  94struct aa_ns *__aa_find_or_create_ns(struct aa_ns *parent, const char *name,
  95                                     struct dentry *dir);
  96struct aa_ns *aa_prepare_ns(struct aa_ns *root, const char *name);
  97void __aa_remove_ns(struct aa_ns *ns);
  98
  99static inline struct aa_profile *aa_deref_parent(struct aa_profile *p)
 100{
 101        return rcu_dereference_protected(p->parent,
 102                                         mutex_is_locked(&p->ns->lock));
 103}
 104
 105/**
 106 * aa_get_ns - increment references count on @ns
 107 * @ns: namespace to increment reference count of (MAYBE NULL)
 108 *
 109 * Returns: pointer to @ns, if @ns is NULL returns NULL
 110 * Requires: @ns must be held with valid refcount when called
 111 */
 112static inline struct aa_ns *aa_get_ns(struct aa_ns *ns)
 113{
 114        if (ns)
 115                aa_get_profile(ns->unconfined);
 116
 117        return ns;
 118}
 119
 120/**
 121 * aa_put_ns - decrement refcount on @ns
 122 * @ns: namespace to put reference of
 123 *
 124 * Decrement reference count of @ns and if no longer in use free it
 125 */
 126static inline void aa_put_ns(struct aa_ns *ns)
 127{
 128        if (ns)
 129                aa_put_profile(ns->unconfined);
 130}
 131
 132/**
 133 * __aa_findn_ns - find a namespace on a list by @name
 134 * @head: list to search for namespace on  (NOT NULL)
 135 * @name: name of namespace to look for  (NOT NULL)
 136 * @n: length of @name
 137 * Returns: unrefcounted namespace
 138 *
 139 * Requires: rcu_read_lock be held
 140 */
 141static inline struct aa_ns *__aa_findn_ns(struct list_head *head,
 142                                          const char *name, size_t n)
 143{
 144        return (struct aa_ns *)__policy_strn_find(head, name, n);
 145}
 146
 147static inline struct aa_ns *__aa_find_ns(struct list_head *head,
 148                                         const char *name)
 149{
 150        return __aa_findn_ns(head, name, strlen(name));
 151}
 152
 153static inline struct aa_ns *__aa_lookup_ns(struct aa_ns *base,
 154                                           const char *hname)
 155{
 156        return __aa_lookupn_ns(base, hname, strlen(hname));
 157}
 158
 159static inline struct aa_ns *aa_lookup_ns(struct aa_ns *view, const char *name)
 160{
 161        return aa_lookupn_ns(view, name, strlen(name));
 162}
 163
 164#endif /* AA_NAMESPACE_H */
 165