policy.h revision 038165070aa55375d4bdd2f84b34a486feca63d6
1/* 2 * AppArmor security module 3 * 4 * This file contains AppArmor policy definitions. 5 * 6 * Copyright (C) 1998-2008 Novell/SUSE 7 * Copyright 2009-2010 Canonical Ltd. 8 * 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 12 * License. 13 */ 14 15#ifndef __AA_POLICY_H 16#define __AA_POLICY_H 17 18#include <linux/capability.h> 19#include <linux/cred.h> 20#include <linux/kref.h> 21#include <linux/sched.h> 22#include <linux/slab.h> 23#include <linux/socket.h> 24 25#include "apparmor.h" 26#include "audit.h" 27#include "capability.h" 28#include "domain.h" 29#include "file.h" 30#include "resource.h" 31 32extern const char *const profile_mode_names[]; 33#define APPARMOR_NAMES_MAX_INDEX 3 34 35#define PROFILE_MODE(_profile, _mode) \ 36 ((aa_g_profile_mode == (_mode)) || \ 37 ((_profile)->mode == (_mode))) 38 39#define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN) 40 41#define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL) 42 43#define PROFILE_IS_HAT(_profile) ((_profile)->flags & PFLAG_HAT) 44 45#define PROFILE_INVALID(_profile) ((_profile)->flags & PFLAG_INVALID) 46 47#define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2) 48 49/* 50 * FIXME: currently need a clean way to replace and remove profiles as a 51 * set. It should be done at the namespace level. 52 * Either, with a set of profiles loaded at the namespace level or via 53 * a mark and remove marked interface. 54 */ 55enum profile_mode { 56 APPARMOR_ENFORCE, /* enforce access rules */ 57 APPARMOR_COMPLAIN, /* allow and log access violations */ 58 APPARMOR_KILL, /* kill task on access violation */ 59 APPARMOR_UNCONFINED, /* profile set to unconfined */ 60}; 61 62enum profile_flags { 63 PFLAG_HAT = 1, /* profile is a hat */ 64 PFLAG_NULL = 4, /* profile is null learning profile */ 65 PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */ 66 PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */ 67 PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */ 68 PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */ 69 PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */ 70 PFLAG_INVALID = 0x200, /* profile replaced/removed */ 71 PFLAG_NS_COUNT = 0x400, /* carries NS ref count */ 72 73 /* These flags must correspond with PATH_flags */ 74 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ 75}; 76 77struct aa_profile; 78 79/* struct aa_policy - common part of both namespaces and profiles 80 * @name: name of the object 81 * @hname - The hierarchical name 82 * @list: list policy object is on 83 * @profiles: head of the profiles list contained in the object 84 */ 85struct aa_policy { 86 char *name; 87 char *hname; 88 struct list_head list; 89 struct list_head profiles; 90}; 91 92/* struct aa_ns_acct - accounting of profiles in namespace 93 * @max_size: maximum space allowed for all profiles in namespace 94 * @max_count: maximum number of profiles that can be in this namespace 95 * @size: current size of profiles 96 * @count: current count of profiles (includes null profiles) 97 */ 98struct aa_ns_acct { 99 int max_size; 100 int max_count; 101 int size; 102 int count; 103}; 104 105/* struct aa_namespace - namespace for a set of profiles 106 * @base: common policy 107 * @parent: parent of namespace 108 * @lock: lock for modifying the object 109 * @acct: accounting for the namespace 110 * @unconfined: special unconfined profile for the namespace 111 * @sub_ns: list of namespaces under the current namespace. 112 * @uniq_null: uniq value used for null learning profiles 113 * 114 * An aa_namespace defines the set profiles that are searched to determine 115 * which profile to attach to a task. Profiles can not be shared between 116 * aa_namespaces and profile names within a namespace are guaranteed to be 117 * unique. When profiles in separate namespaces have the same name they 118 * are NOT considered to be equivalent. 119 * 120 * Namespaces are hierarchical and only namespaces and profiles below the 121 * current namespace are visible. 122 * 123 * Namespace names must be unique and can not contain the characters :/\0 124 * 125 * FIXME TODO: add vserver support of namespaces (can it all be done in 126 * userspace?) 127 */ 128struct aa_namespace { 129 struct aa_policy base; 130 struct aa_namespace *parent; 131 struct mutex lock; 132 struct aa_ns_acct acct; 133 struct aa_profile *unconfined; 134 struct list_head sub_ns; 135 atomic_t uniq_null; 136}; 137 138/* struct aa_policydb - match engine for a policy 139 * dfa: dfa pattern match 140 * start: set of start states for the different classes of data 141 */ 142struct aa_policydb { 143 /* Generic policy DFA specific rule types will be subsections of it */ 144 struct aa_dfa *dfa; 145 unsigned int start[AA_CLASS_LAST + 1]; 146 147}; 148 149struct aa_replacedby { 150 struct kref count; 151 struct aa_profile __rcu *profile; 152}; 153 154 155/* struct aa_profile - basic confinement data 156 * @base - base components of the profile (name, refcount, lists, lock ...) 157 * @count: reference count of the obj 158 * @rcu: rcu head used when removing from @list 159 * @parent: parent of profile 160 * @ns: namespace the profile is in 161 * @replacedby: is set to the profile that replaced this profile 162 * @rename: optional profile name that this profile renamed 163 * @xmatch: optional extended matching for unconfined executables names 164 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 165 * @audit: the auditing mode of the profile 166 * @mode: the enforcement mode of the profile 167 * @flags: flags controlling profile behavior 168 * @path_flags: flags controlling path generation behavior 169 * @size: the memory consumed by this profiles rules 170 * @policy: general match rules governing policy 171 * @file: The set of rules governing basic file access and domain transitions 172 * @caps: capabilities for the profile 173 * @rlimits: rlimits for the profile 174 * 175 * The AppArmor profile contains the basic confinement data. Each profile 176 * has a name, and exists in a namespace. The @name and @exec_match are 177 * used to determine profile attachment against unconfined tasks. All other 178 * attachments are determined by profile X transition rules. 179 * 180 * The @replacedby struct is write protected by the profile lock. 181 * 182 * Profiles have a hierarchy where hats and children profiles keep 183 * a reference to their parent. 184 * 185 * Profile names can not begin with a : and can not contain the \0 186 * character. If a profile name begins with / it will be considered when 187 * determining profile attachment on "unconfined" tasks. 188 */ 189struct aa_profile { 190 struct aa_policy base; 191 struct kref count; 192 struct rcu_head rcu; 193 struct aa_profile __rcu *parent; 194 195 struct aa_namespace *ns; 196 struct aa_replacedby *replacedby; 197 const char *rename; 198 199 struct aa_dfa *xmatch; 200 int xmatch_len; 201 enum audit_mode audit; 202 long mode; 203 long flags; 204 u32 path_flags; 205 int size; 206 207 struct aa_policydb policy; 208 struct aa_file_rules file; 209 struct aa_caps caps; 210 struct aa_rlimit rlimits; 211}; 212 213extern struct aa_namespace *root_ns; 214extern enum profile_mode aa_g_profile_mode; 215 216void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 217 218bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view); 219const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child); 220int aa_alloc_root_ns(void); 221void aa_free_root_ns(void); 222void aa_free_namespace_kref(struct kref *kref); 223 224struct aa_namespace *aa_find_namespace(struct aa_namespace *root, 225 const char *name); 226 227 228void aa_free_replacedby_kref(struct kref *kref); 229struct aa_profile *aa_alloc_profile(const char *name); 230struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); 231void aa_free_profile(struct aa_profile *profile); 232void aa_free_profile_kref(struct kref *kref); 233struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 234struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); 235struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name); 236 237ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace); 238ssize_t aa_remove_profiles(char *name, size_t size); 239 240#define PROF_ADD 1 241#define PROF_REPLACE 0 242 243#define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED) 244 245 246/** 247 * aa_get_profile - increment refcount on profile @p 248 * @p: profile (MAYBE NULL) 249 * 250 * Returns: pointer to @p if @p is NULL will return NULL 251 * Requires: @p must be held with valid refcount when called 252 */ 253static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 254{ 255 if (p) 256 kref_get(&(p->count)); 257 258 return p; 259} 260 261/** 262 * aa_get_profile_not0 - increment refcount on profile @p found via lookup 263 * @p: profile (MAYBE NULL) 264 * 265 * Returns: pointer to @p if @p is NULL will return NULL 266 * Requires: @p must be held with valid refcount when called 267 */ 268static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) 269{ 270 if (p && kref_get_not0(&p->count)) 271 return p; 272 273 return NULL; 274} 275 276/** 277 * aa_get_profile_rcu - increment a refcount profile that can be replaced 278 * @p: pointer to profile that can be replaced (NOT NULL) 279 * 280 * Returns: pointer to a refcounted profile. 281 * else NULL if no profile 282 */ 283static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) 284{ 285 struct aa_profile *c; 286 287 rcu_read_lock(); 288 do { 289 c = rcu_dereference(*p); 290 } while (c && !kref_get_not0(&c->count)); 291 rcu_read_unlock(); 292 293 return c; 294} 295 296/** 297 * aa_get_newest_profile - find the newest version of @profile 298 * @profile: the profile to check for newer versions of 299 * 300 * Returns: refcounted newest version of @profile taking into account 301 * replacement, renames and removals 302 * return @profile. 303 */ 304static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p) 305{ 306 if (!p) 307 return NULL; 308 309 if (PROFILE_INVALID(p)) 310 return aa_get_profile_rcu(&p->replacedby->profile); 311 312 return aa_get_profile(p); 313} 314 315/** 316 * aa_put_profile - decrement refcount on profile @p 317 * @p: profile (MAYBE NULL) 318 */ 319static inline void aa_put_profile(struct aa_profile *p) 320{ 321 if (p) 322 kref_put(&p->count, aa_free_profile_kref); 323} 324 325static inline struct aa_replacedby *aa_get_replacedby(struct aa_replacedby *p) 326{ 327 if (p) 328 kref_get(&(p->count)); 329 330 return p; 331} 332 333static inline void aa_put_replacedby(struct aa_replacedby *p) 334{ 335 if (p) 336 kref_put(&p->count, aa_free_replacedby_kref); 337} 338 339/* requires profile list write lock held */ 340static inline void __aa_update_replacedby(struct aa_profile *orig, 341 struct aa_profile *new) 342{ 343 struct aa_profile *tmp = rcu_dereference(orig->replacedby->profile); 344 rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new)); 345 orig->flags |= PFLAG_INVALID; 346 aa_put_profile(tmp); 347} 348 349/** 350 * aa_get_namespace - increment references count on @ns 351 * @ns: namespace to increment reference count of (MAYBE NULL) 352 * 353 * Returns: pointer to @ns, if @ns is NULL returns NULL 354 * Requires: @ns must be held with valid refcount when called 355 */ 356static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) 357{ 358 if (ns) 359 aa_get_profile(ns->unconfined); 360 361 return ns; 362} 363 364/** 365 * aa_put_namespace - decrement refcount on @ns 366 * @ns: namespace to put reference of 367 * 368 * Decrement reference count of @ns and if no longer in use free it 369 */ 370static inline void aa_put_namespace(struct aa_namespace *ns) 371{ 372 if (ns) 373 aa_put_profile(ns->unconfined); 374} 375 376static inline int AUDIT_MODE(struct aa_profile *profile) 377{ 378 if (aa_g_audit != AUDIT_NORMAL) 379 return aa_g_audit; 380 381 return profile->audit; 382} 383 384bool aa_may_manage_policy(int op); 385 386#endif /* __AA_POLICY_H */ 387