policy.h revision 77b071b34045a0c65d0e1f85f3d47fd2b8b7a8a1
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}; 60 61enum profile_flags { 62 PFLAG_HAT = 1, /* profile is a hat */ 63 PFLAG_UNCONFINED = 2, /* profile is an unconfined profile */ 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 72 /* These flags must correspond with PATH_flags */ 73 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ 74}; 75 76struct aa_profile; 77 78/* struct aa_policy - common part of both namespaces and profiles 79 * @name: name of the object 80 * @hname - The hierarchical name 81 * @count: reference count of the obj 82 * @list: list policy object is on 83 * @rcu: rcu head used when removing from @list 84 * @profiles: head of the profiles list contained in the object 85 */ 86struct aa_policy { 87 char *name; 88 char *hname; 89 struct kref count; 90 struct list_head list; 91 struct list_head profiles; 92 struct rcu_head rcu; 93}; 94 95/* struct aa_ns_acct - accounting of profiles in namespace 96 * @max_size: maximum space allowed for all profiles in namespace 97 * @max_count: maximum number of profiles that can be in this namespace 98 * @size: current size of profiles 99 * @count: current count of profiles (includes null profiles) 100 */ 101struct aa_ns_acct { 102 int max_size; 103 int max_count; 104 int size; 105 int count; 106}; 107 108/* struct aa_namespace - namespace for a set of profiles 109 * @base: common policy 110 * @parent: parent of namespace 111 * @lock: lock for modifying the object 112 * @acct: accounting for the namespace 113 * @unconfined: special unconfined profile for the namespace 114 * @sub_ns: list of namespaces under the current namespace. 115 * @uniq_null: uniq value used for null learning profiles 116 * 117 * An aa_namespace defines the set profiles that are searched to determine 118 * which profile to attach to a task. Profiles can not be shared between 119 * aa_namespaces and profile names within a namespace are guaranteed to be 120 * unique. When profiles in separate namespaces have the same name they 121 * are NOT considered to be equivalent. 122 * 123 * Namespaces are hierarchical and only namespaces and profiles below the 124 * current namespace are visible. 125 * 126 * Namespace names must be unique and can not contain the characters :/\0 127 * 128 * FIXME TODO: add vserver support of namespaces (can it all be done in 129 * userspace?) 130 */ 131struct aa_namespace { 132 struct aa_policy base; 133 struct aa_namespace *parent; 134 struct mutex lock; 135 struct aa_ns_acct acct; 136 struct aa_profile *unconfined; 137 struct list_head sub_ns; 138 atomic_t uniq_null; 139}; 140 141/* struct aa_policydb - match engine for a policy 142 * dfa: dfa pattern match 143 * start: set of start states for the different classes of data 144 */ 145struct aa_policydb { 146 /* Generic policy DFA specific rule types will be subsections of it */ 147 struct aa_dfa *dfa; 148 unsigned int start[AA_CLASS_LAST + 1]; 149 150}; 151 152struct aa_replacedby { 153 struct kref count; 154 struct aa_profile __rcu *profile; 155}; 156 157 158/* struct aa_profile - basic confinement data 159 * @base - base components of the profile (name, refcount, lists, lock ...) 160 * @parent: parent of profile 161 * @ns: namespace the profile is in 162 * @replacedby: is set to the profile that replaced this profile 163 * @rename: optional profile name that this profile renamed 164 * @xmatch: optional extended matching for unconfined executables names 165 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 166 * @audit: the auditing mode of the profile 167 * @mode: the enforcement mode of the profile 168 * @flags: flags controlling profile behavior 169 * @path_flags: flags controlling path generation behavior 170 * @size: the memory consumed by this profiles rules 171 * @policy: general match rules governing policy 172 * @file: The set of rules governing basic file access and domain transitions 173 * @caps: capabilities for the profile 174 * @rlimits: rlimits for the profile 175 * 176 * The AppArmor profile contains the basic confinement data. Each profile 177 * has a name, and exists in a namespace. The @name and @exec_match are 178 * used to determine profile attachment against unconfined tasks. All other 179 * attachments are determined by profile X transition rules. 180 * 181 * The @replacedby struct is write protected by the profile lock. 182 * 183 * Profiles have a hierarchy where hats and children profiles keep 184 * a reference to their parent. 185 * 186 * Profile names can not begin with a : and can not contain the \0 187 * character. If a profile name begins with / it will be considered when 188 * determining profile attachment on "unconfined" tasks. 189 */ 190struct aa_profile { 191 struct aa_policy base; 192 struct aa_profile __rcu *parent; 193 194 struct aa_namespace *ns; 195 struct aa_replacedby *replacedby; 196 const char *rename; 197 198 struct aa_dfa *xmatch; 199 int xmatch_len; 200 enum audit_mode audit; 201 enum profile_mode mode; 202 long flags; 203 u32 path_flags; 204 int size; 205 206 struct aa_policydb policy; 207 struct aa_file_rules file; 208 struct aa_caps caps; 209 struct aa_rlimit rlimits; 210}; 211 212extern struct aa_namespace *root_ns; 213extern enum profile_mode aa_g_profile_mode; 214 215void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 216 217bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view); 218const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child); 219int aa_alloc_root_ns(void); 220void aa_free_root_ns(void); 221void aa_free_namespace_kref(struct kref *kref); 222 223struct aa_namespace *aa_find_namespace(struct aa_namespace *root, 224 const char *name); 225 226static inline struct aa_policy *aa_get_common(struct aa_policy *c) 227{ 228 if (c) 229 kref_get(&c->count); 230 231 return c; 232} 233 234/** 235 * aa_get_namespace - increment references count on @ns 236 * @ns: namespace to increment reference count of (MAYBE NULL) 237 * 238 * Returns: pointer to @ns, if @ns is NULL returns NULL 239 * Requires: @ns must be held with valid refcount when called 240 */ 241static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) 242{ 243 if (ns) 244 kref_get(&(ns->base.count)); 245 246 return ns; 247} 248 249/** 250 * aa_put_namespace - decrement refcount on @ns 251 * @ns: namespace to put reference of 252 * 253 * Decrement reference count of @ns and if no longer in use free it 254 */ 255static inline void aa_put_namespace(struct aa_namespace *ns) 256{ 257 if (ns) 258 kref_put(&ns->base.count, aa_free_namespace_kref); 259} 260 261void aa_free_replacedby_kref(struct kref *kref); 262struct aa_profile *aa_alloc_profile(const char *name); 263struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); 264void aa_free_profile_kref(struct kref *kref); 265struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 266struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); 267struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name); 268 269ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace); 270ssize_t aa_remove_profiles(char *name, size_t size); 271 272#define PROF_ADD 1 273#define PROF_REPLACE 0 274 275#define unconfined(X) ((X)->flags & PFLAG_UNCONFINED) 276 277 278/** 279 * aa_get_profile - increment refcount on profile @p 280 * @p: profile (MAYBE NULL) 281 * 282 * Returns: pointer to @p if @p is NULL will return NULL 283 * Requires: @p must be held with valid refcount when called 284 */ 285static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 286{ 287 if (p) 288 kref_get(&(p->base.count)); 289 290 return p; 291} 292 293/** 294 * aa_get_profile_not0 - increment refcount on profile @p found via lookup 295 * @p: profile (MAYBE NULL) 296 * 297 * Returns: pointer to @p if @p is NULL will return NULL 298 * Requires: @p must be held with valid refcount when called 299 */ 300static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) 301{ 302 if (p && kref_get_not0(&p->base.count)) 303 return p; 304 305 return NULL; 306} 307 308/** 309 * aa_get_profile_rcu - increment a refcount profile that can be replaced 310 * @p: pointer to profile that can be replaced (NOT NULL) 311 * 312 * Returns: pointer to a refcounted profile. 313 * else NULL if no profile 314 */ 315static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) 316{ 317 struct aa_profile *c; 318 319 rcu_read_lock(); 320 do { 321 c = rcu_dereference(*p); 322 } while (c && !kref_get_not0(&c->base.count)); 323 rcu_read_unlock(); 324 325 return c; 326} 327 328/** 329 * aa_get_newest_profile - find the newest version of @profile 330 * @profile: the profile to check for newer versions of 331 * 332 * Returns: refcounted newest version of @profile taking into account 333 * replacement, renames and removals 334 * return @profile. 335 */ 336static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p) 337{ 338 if (!p) 339 return NULL; 340 341 if (PROFILE_INVALID(p)) 342 return aa_get_profile_rcu(&p->replacedby->profile); 343 344 return aa_get_profile(p); 345} 346 347/** 348 * aa_put_profile - decrement refcount on profile @p 349 * @p: profile (MAYBE NULL) 350 */ 351static inline void aa_put_profile(struct aa_profile *p) 352{ 353 if (p) 354 kref_put(&p->base.count, aa_free_profile_kref); 355} 356 357static inline struct aa_replacedby *aa_get_replacedby(struct aa_replacedby *p) 358{ 359 if (p) 360 kref_get(&(p->count)); 361 362 return p; 363} 364 365static inline void aa_put_replacedby(struct aa_replacedby *p) 366{ 367 if (p) 368 kref_put(&p->count, aa_free_replacedby_kref); 369} 370 371/* requires profile list write lock held */ 372static inline void __aa_update_replacedby(struct aa_profile *orig, 373 struct aa_profile *new) 374{ 375 struct aa_profile *tmp = rcu_dereference(orig->replacedby->profile); 376 rcu_assign_pointer(orig->replacedby->profile, aa_get_profile(new)); 377 orig->flags |= PFLAG_INVALID; 378 aa_put_profile(tmp); 379} 380 381static inline int AUDIT_MODE(struct aa_profile *profile) 382{ 383 if (aa_g_audit != AUDIT_NORMAL) 384 return aa_g_audit; 385 386 return profile->audit; 387} 388 389bool aa_may_manage_policy(int op); 390 391#endif /* __AA_POLICY_H */ 392