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/*
* AppArmor security module
*
* This file contains AppArmor policy definitions.
*
* Copyright (C) 1998-2008 Novell/SUSE
* Copyright 2009-2010 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_POLICY_H
#define __AA_POLICY_H
#include <linux/capability.h>
#include <linux/cred.h>
#include <linux/kref.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/socket.h>
#include "apparmor.h"
#include "audit.h"
#include "capability.h"
#include "domain.h"
#include "file.h"
#include "resource.h"
extern const char *const aa_profile_mode_names[];
#define APPARMOR_MODE_NAMES_MAX_INDEX 4
#define PROFILE_MODE(_profile, _mode) \
((aa_g_profile_mode == (_mode)) || \
((_profile)->mode == (_mode)))
#define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
#define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
#define PROFILE_IS_HAT(_profile) ((_profile)->flags & PFLAG_HAT)
#define PROFILE_INVALID(_profile) ((_profile)->flags & PFLAG_INVALID)
#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
/*
* FIXME: currently need a clean way to replace and remove profiles as a
* set. It should be done at the namespace level.
* Either, with a set of profiles loaded at the namespace level or via
* a mark and remove marked interface.
*/
enum profile_mode {
APPARMOR_ENFORCE, /* enforce access rules */
APPARMOR_COMPLAIN, /* allow and log access violations */
APPARMOR_KILL, /* kill task on access violation */
APPARMOR_UNCONFINED, /* profile set to unconfined */
};
enum profile_flags {
PFLAG_HAT = 1, /* profile is a hat */
PFLAG_NULL = 4, /* profile is null learning profile */
PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */
PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */
PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */
PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */
PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */
PFLAG_INVALID = 0x200, /* profile replaced/removed */
PFLAG_NS_COUNT = 0x400, /* carries NS ref count */
/* These flags must correspond with PATH_flags */
PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */
};
struct aa_profile;
/* struct aa_policy - common part of both namespaces and profiles
* @name: name of the object
* @hname - The hierarchical name
* @list: list policy object is on
* @profiles: head of the profiles list contained in the object
*/
struct aa_policy {
char *name;
char *hname;
struct list_head list;
struct list_head profiles;
};
/* struct aa_ns_acct - accounting of profiles in namespace
* @max_size: maximum space allowed for all profiles in namespace
* @max_count: maximum number of profiles that can be in this namespace
* @size: current size of profiles
* @count: current count of profiles (includes null profiles)
*/
struct aa_ns_acct {
int max_size;
int max_count;
int size;
int count;
};
/* struct aa_namespace - namespace for a set of profiles
* @base: common policy
* @parent: parent of namespace
* @lock: lock for modifying the object
* @acct: accounting for the namespace
* @unconfined: special unconfined profile for the namespace
* @sub_ns: list of namespaces under the current namespace.
* @uniq_null: uniq value used for null learning profiles
* @uniq_id: a unique id count for the profiles in the namespace
* @dents: dentries for the namespaces file entries in apparmorfs
*
* An aa_namespace defines the set profiles that are searched to determine
* which profile to attach to a task. Profiles can not be shared between
* aa_namespaces and profile names within a namespace are guaranteed to be
* unique. When profiles in separate namespaces have the same name they
* are NOT considered to be equivalent.
*
* Namespaces are hierarchical and only namespaces and profiles below the
* current namespace are visible.
*
* Namespace names must be unique and can not contain the characters :/\0
*
* FIXME TODO: add vserver support of namespaces (can it all be done in
* userspace?)
*/
struct aa_namespace {
struct aa_policy base;
struct aa_namespace *parent;
struct mutex lock;
struct aa_ns_acct acct;
struct aa_profile *unconfined;
struct list_head sub_ns;
atomic_t uniq_null;
long uniq_id;
struct dentry *dents[AAFS_NS_SIZEOF];
};
/* struct aa_policydb - match engine for a policy
* dfa: dfa pattern match
* start: set of start states for the different classes of data
*/
struct aa_policydb {
/* Generic policy DFA specific rule types will be subsections of it */
struct aa_dfa *dfa;
unsigned int start[AA_CLASS_LAST + 1];
};
struct aa_replacedby {
struct kref count;
struct aa_profile __rcu *profile;
};
/* struct aa_profile - basic confinement data
* @base - base components of the profile (name, refcount, lists, lock ...)
* @count: reference count of the obj
* @rcu: rcu head used when removing from @list
* @parent: parent of profile
* @ns: namespace the profile is in
* @replacedby: is set to the profile that replaced this profile
* @rename: optional profile name that this profile renamed
* @attach: human readable attachment string
* @xmatch: optional extended matching for unconfined executables names
* @xmatch_len: xmatch prefix len, used to determine xmatch priority
* @audit: the auditing mode of the profile
* @mode: the enforcement mode of the profile
* @flags: flags controlling profile behavior
* @path_flags: flags controlling path generation behavior
* @size: the memory consumed by this profiles rules
* @policy: general match rules governing policy
* @file: The set of rules governing basic file access and domain transitions
* @caps: capabilities for the profile
* @rlimits: rlimits for the profile
*
* @dents: dentries for the profiles file entries in apparmorfs
* @dirname: name of the profile dir in apparmorfs
*
* The AppArmor profile contains the basic confinement data. Each profile
* has a name, and exists in a namespace. The @name and @exec_match are
* used to determine profile attachment against unconfined tasks. All other
* attachments are determined by profile X transition rules.
*
* The @replacedby struct is write protected by the profile lock.
*
* Profiles have a hierarchy where hats and children profiles keep
* a reference to their parent.
*
* Profile names can not begin with a : and can not contain the \0
* character. If a profile name begins with / it will be considered when
* determining profile attachment on "unconfined" tasks.
*/
struct aa_profile {
struct aa_policy base;
struct kref count;
struct rcu_head rcu;
struct aa_profile __rcu *parent;
struct aa_namespace *ns;
struct aa_replacedby *replacedby;
const char *rename;
const char *attach;
struct aa_dfa *xmatch;
int xmatch_len;
enum audit_mode audit;
long mode;
long flags;
u32 path_flags;
int size;
struct aa_policydb policy;
struct aa_file_rules file;
struct aa_caps caps;
struct aa_rlimit rlimits;
unsigned char *hash;
char *dirname;
struct dentry *dents[AAFS_PROF_SIZEOF];
};
extern struct aa_namespace *root_ns;
extern enum profile_mode aa_g_profile_mode;
void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view);
const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child);
int aa_alloc_root_ns(void);
void aa_free_root_ns(void);
void aa_free_namespace_kref(struct kref *kref);
struct aa_namespace *aa_find_namespace(struct aa_namespace *root,
const char *name);
void aa_free_replacedby_kref(struct kref *kref);
struct aa_profile *aa_alloc_profile(const char *name);
struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat);
void aa_free_profile(struct aa_profile *profile);
void aa_free_profile_kref(struct kref *kref);
struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name);
struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name);
ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace);
ssize_t aa_remove_profiles(char *name, size_t size);
#define PROF_ADD 1
#define PROF_REPLACE 0
#define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
static inline struct aa_profile *aa_deref_parent(struct aa_profile *p)
{
return rcu_dereference_protected(p->parent,
mutex_is_locked(&p->ns->lock));
}
/**
* aa_get_profile - increment refcount on profile @p
* @p: profile (MAYBE NULL)
*
* Returns: pointer to @p if @p is NULL will return NULL
* Requires: @p must be held with valid refcount when called
*/
static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
{
if (p)
kref_get(&(p->count));
return p;
}
/**
* aa_get_profile_not0 - increment refcount on profile @p found via lookup
* @p: profile (MAYBE NULL)
*
* Returns: pointer to @p if @p is NULL will return NULL
* Requires: @p must be held with valid refcount when called
*/
static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
{
if (p && kref_get_not0(&p->count))
return p;
return NULL;
}
/**
* aa_get_profile_rcu - increment a refcount profile that can be replaced
* @p: pointer to profile that can be replaced (NOT NULL)
*
* Returns: pointer to a refcounted profile.
* else NULL if no profile
*/
static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
{
struct aa_profile *c;
rcu_read_lock();
do {
c = rcu_dereference(*p);
} while (c && !kref_get_not0(&c->count));
rcu_read_unlock();
return c;
}
/**
* aa_get_newest_profile - find the newest version of @profile
* @profile: the profile to check for newer versions of
*
* Returns: refcounted newest version of @profile taking into account
* replacement, renames and removals
* return @profile.
*/
static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
{
if (!p)
return NULL;
if (PROFILE_INVALID(p))
return aa_get_profile_rcu(&p->replacedby->profile);
return aa_get_profile(p);
}
/**
* aa_put_profile - decrement refcount on profile @p
* @p: profile (MAYBE NULL)
*/
static inline void aa_put_profile(struct aa_profile *p)
{
if (p)
kref_put(&p->count, aa_free_profile_kref);
}
static inline struct aa_replacedby *aa_get_replacedby(struct aa_replacedby *p)
{
if (p)
kref_get(&(p->count));
return p;
}
static inline void aa_put_replacedby(struct aa_replacedby *p)
{
if (p)
kref_put(&p->count, aa_free_replacedby_kref);
}
/* requires profile list write lock held */
static inline void __aa_update_replacedby(struct aa_profile *orig,
struct aa_profile *new)
{
struct aa_profile *tmp = rcu_dereference(orig->replacedby->profile);
rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new));
orig->flags |= PFLAG_INVALID;
aa_put_profile(tmp);
}
/**
* aa_get_namespace - increment references count on @ns
* @ns: namespace to increment reference count of (MAYBE NULL)
*
* Returns: pointer to @ns, if @ns is NULL returns NULL
* Requires: @ns must be held with valid refcount when called
*/
static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns)
{
if (ns)
aa_get_profile(ns->unconfined);
return ns;
}
/**
* aa_put_namespace - decrement refcount on @ns
* @ns: namespace to put reference of
*
* Decrement reference count of @ns and if no longer in use free it
*/
static inline void aa_put_namespace(struct aa_namespace *ns)
{
if (ns)
aa_put_profile(ns->unconfined);
}
static inline int AUDIT_MODE(struct aa_profile *profile)
{
if (aa_g_audit != AUDIT_NORMAL)
return aa_g_audit;
return profile->audit;
}
bool aa_may_manage_policy(int op);
#endif /* __AA_POLICY_H */