policy.h revision 01e2b670aa898a39259bc85c78e3d74820f4d3b6
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 on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2) 46 47/* 48 * FIXME: currently need a clean way to replace and remove profiles as a 49 * set. It should be done at the namespace level. 50 * Either, with a set of profiles loaded at the namespace level or via 51 * a mark and remove marked interface. 52 */ 53enum profile_mode { 54 APPARMOR_ENFORCE, /* enforce access rules */ 55 APPARMOR_COMPLAIN, /* allow and log access violations */ 56 APPARMOR_KILL, /* kill task on access violation */ 57}; 58 59enum profile_flags { 60 PFLAG_HAT = 1, /* profile is a hat */ 61 PFLAG_UNCONFINED = 2, /* profile is an unconfined profile */ 62 PFLAG_NULL = 4, /* profile is null learning profile */ 63 PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */ 64 PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */ 65 PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */ 66 PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */ 67 PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */ 68 69 /* These flags must correspond with PATH_flags */ 70 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ 71}; 72 73struct aa_profile; 74 75/* struct aa_policy - common part of both namespaces and profiles 76 * @name: name of the object 77 * @hname - The hierarchical name 78 * @count: reference count of the obj 79 * @list: list policy object is on 80 * @rcu: rcu head used when removing from @list 81 * @profiles: head of the profiles list contained in the object 82 */ 83struct aa_policy { 84 char *name; 85 char *hname; 86 struct kref count; 87 struct list_head list; 88 struct list_head profiles; 89 struct rcu_head rcu; 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}; 148 149/* struct aa_profile - basic confinement data 150 * @base - base components of the profile (name, refcount, lists, lock ...) 151 * @parent: parent of profile 152 * @ns: namespace the profile is in 153 * @replacedby: is set to the profile that replaced this profile 154 * @rename: optional profile name that this profile renamed 155 * @xmatch: optional extended matching for unconfined executables names 156 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 157 * @audit: the auditing mode of the profile 158 * @mode: the enforcement mode of the profile 159 * @flags: flags controlling profile behavior 160 * @path_flags: flags controlling path generation behavior 161 * @size: the memory consumed by this profiles rules 162 * @policy: general match rules governing policy 163 * @file: The set of rules governing basic file access and domain transitions 164 * @caps: capabilities for the profile 165 * @rlimits: rlimits for the profile 166 * 167 * The AppArmor profile contains the basic confinement data. Each profile 168 * has a name, and exists in a namespace. The @name and @exec_match are 169 * used to determine profile attachment against unconfined tasks. All other 170 * attachments are determined by profile X transition rules. 171 * 172 * The @replacedby field is write protected by the profile lock. Reads 173 * are assumed to be atomic. 174 * 175 * Profiles have a hierarchy where hats and children profiles keep 176 * a reference to their parent. 177 * 178 * Profile names can not begin with a : and can not contain the \0 179 * character. If a profile name begins with / it will be considered when 180 * determining profile attachment on "unconfined" tasks. 181 */ 182struct aa_profile { 183 struct aa_policy base; 184 struct aa_profile __rcu *parent; 185 186 struct aa_namespace *ns; 187 struct aa_profile *replacedby; 188 const char *rename; 189 190 struct aa_dfa *xmatch; 191 int xmatch_len; 192 enum audit_mode audit; 193 enum profile_mode mode; 194 u32 flags; 195 u32 path_flags; 196 int size; 197 198 struct aa_policydb policy; 199 struct aa_file_rules file; 200 struct aa_caps caps; 201 struct aa_rlimit rlimits; 202}; 203 204extern struct aa_namespace *root_ns; 205extern enum profile_mode aa_g_profile_mode; 206 207void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 208 209bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view); 210const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child); 211int aa_alloc_root_ns(void); 212void aa_free_root_ns(void); 213void aa_free_namespace_kref(struct kref *kref); 214 215struct aa_namespace *aa_find_namespace(struct aa_namespace *root, 216 const char *name); 217 218static inline struct aa_policy *aa_get_common(struct aa_policy *c) 219{ 220 if (c) 221 kref_get(&c->count); 222 223 return c; 224} 225 226/** 227 * aa_get_namespace - increment references count on @ns 228 * @ns: namespace to increment reference count of (MAYBE NULL) 229 * 230 * Returns: pointer to @ns, if @ns is NULL returns NULL 231 * Requires: @ns must be held with valid refcount when called 232 */ 233static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) 234{ 235 if (ns) 236 kref_get(&(ns->base.count)); 237 238 return ns; 239} 240 241/** 242 * aa_put_namespace - decrement refcount on @ns 243 * @ns: namespace to put reference of 244 * 245 * Decrement reference count of @ns and if no longer in use free it 246 */ 247static inline void aa_put_namespace(struct aa_namespace *ns) 248{ 249 if (ns) 250 kref_put(&ns->base.count, aa_free_namespace_kref); 251} 252 253struct aa_profile *aa_alloc_profile(const char *name); 254struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); 255void aa_free_profile_kref(struct kref *kref); 256struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 257struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); 258struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name); 259 260ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace); 261ssize_t aa_remove_profiles(char *name, size_t size); 262 263#define PROF_ADD 1 264#define PROF_REPLACE 0 265 266#define unconfined(X) ((X)->flags & PFLAG_UNCONFINED) 267 268/** 269 * aa_newest_version - find the newest version of @profile 270 * @profile: the profile to check for newer versions of (NOT NULL) 271 * 272 * Returns: newest version of @profile, if @profile is the newest version 273 * return @profile. 274 * 275 * NOTE: the profile returned is not refcounted, The refcount on @profile 276 * must be held until the caller decides what to do with the returned newest 277 * version. 278 */ 279static inline struct aa_profile *aa_newest_version(struct aa_profile *profile) 280{ 281 while (profile->replacedby) 282 profile = profile->replacedby; 283 284 return profile; 285} 286 287/** 288 * aa_get_profile - increment refcount on profile @p 289 * @p: profile (MAYBE NULL) 290 * 291 * Returns: pointer to @p if @p is NULL will return NULL 292 * Requires: @p must be held with valid refcount when called 293 */ 294static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 295{ 296 if (p) 297 kref_get(&(p->base.count)); 298 299 return p; 300} 301 302/** 303 * aa_get_profile_not0 - increment refcount on profile @p found via lookup 304 * @p: profile (MAYBE NULL) 305 * 306 * Returns: pointer to @p if @p is NULL will return NULL 307 * Requires: @p must be held with valid refcount when called 308 */ 309static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) 310{ 311 if (p && kref_get_not0(&p->base.count)) 312 return p; 313 314 return NULL; 315} 316 317/** 318 * aa_get_profile_rcu - increment a refcount profile that can be replaced 319 * @p: pointer to profile that can be replaced (NOT NULL) 320 * 321 * Returns: pointer to a refcounted profile. 322 * else NULL if no profile 323 */ 324static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) 325{ 326 struct aa_profile *c; 327 328 rcu_read_lock(); 329 do { 330 c = rcu_dereference(*p); 331 } while (c && !kref_get_not0(&c->base.count)); 332 rcu_read_unlock(); 333 334 return c; 335} 336 337/** 338 * aa_put_profile - decrement refcount on profile @p 339 * @p: profile (MAYBE NULL) 340 */ 341static inline void aa_put_profile(struct aa_profile *p) 342{ 343 if (p) 344 kref_put(&p->base.count, aa_free_profile_kref); 345} 346 347static inline int AUDIT_MODE(struct aa_profile *profile) 348{ 349 if (aa_g_audit != AUDIT_NORMAL) 350 return aa_g_audit; 351 352 return profile->audit; 353} 354 355bool aa_may_manage_policy(int op); 356 357#endif /* __AA_POLICY_H */ 358