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 32 extern 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 /* 46 * FIXME: currently need a clean way to replace and remove profiles as a 47 * set. It should be done at the namespace level. 48 * Either, with a set of profiles loaded at the namespace level or via 49 * a mark and remove marked interface. 50 */ 51 enum profile_mode { 52 APPARMOR_ENFORCE, /* enforce access rules */ 53 APPARMOR_COMPLAIN, /* allow and log access violations */ 54 APPARMOR_KILL, /* kill task on access violation */ 55 }; 56 57 enum profile_flags { 58 PFLAG_HAT = 1, /* profile is a hat */ 59 PFLAG_UNCONFINED = 2, /* profile is an unconfined profile */ 60 PFLAG_NULL = 4, /* profile is null learning profile */ 61 PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */ 62 PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */ 63 PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */ 64 PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */ 65 PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */ 66 67 /* These flags must correspond with PATH_flags */ 68 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ 69 }; 70 71 struct aa_profile; 72 73 /* struct aa_policy - common part of both namespaces and profiles 74 * @name: name of the object 75 * @hname - The hierarchical name 76 * @count: reference count of the obj 77 * @list: list policy object is on 78 * @profiles: head of the profiles list contained in the object 79 */ 80 struct aa_policy { 81 char *name; 82 char *hname; 83 struct kref count; 84 struct list_head list; 85 struct list_head profiles; 86 }; 87 88 /* struct aa_ns_acct - accounting of profiles in namespace 89 * @max_size: maximum space allowed for all profiles in namespace 90 * @max_count: maximum number of profiles that can be in this namespace 91 * @size: current size of profiles 92 * @count: current count of profiles (includes null profiles) 93 */ 94 struct aa_ns_acct { 95 int max_size; 96 int max_count; 97 int size; 98 int count; 99 }; 100 101 /* struct aa_namespace - namespace for a set of profiles 102 * @base: common policy 103 * @parent: parent of namespace 104 * @lock: lock for modifying the object 105 * @acct: accounting for the namespace 106 * @unconfined: special unconfined profile for the namespace 107 * @sub_ns: list of namespaces under the current namespace. 108 * @uniq_null: uniq value used for null learning profiles 109 * 110 * An aa_namespace defines the set profiles that are searched to determine 111 * which profile to attach to a task. Profiles can not be shared between 112 * aa_namespaces and profile names within a namespace are guaranteed to be 113 * unique. When profiles in separate namespaces have the same name they 114 * are NOT considered to be equivalent. 115 * 116 * Namespaces are hierarchical and only namespaces and profiles below the 117 * current namespace are visible. 118 * 119 * Namespace names must be unique and can not contain the characters :/\0 120 * 121 * FIXME TODO: add vserver support of namespaces (can it all be done in 122 * userspace?) 123 */ 124 struct aa_namespace { 125 struct aa_policy base; 126 struct aa_namespace *parent; 127 rwlock_t lock; 128 struct aa_ns_acct acct; 129 struct aa_profile *unconfined; 130 struct list_head sub_ns; 131 atomic_t uniq_null; 132 }; 133 134 /* struct aa_policydb - match engine for a policy 135 * dfa: dfa pattern match 136 * start: set of start states for the different classes of data 137 */ 138 struct aa_policydb { 139 /* Generic policy DFA specific rule types will be subsections of it */ 140 struct aa_dfa *dfa; 141 unsigned int start[AA_CLASS_LAST + 1]; 142 143 }; 144 145 /* struct aa_profile - basic confinement data 146 * @base - base components of the profile (name, refcount, lists, lock ...) 147 * @parent: parent of profile 148 * @ns: namespace the profile is in 149 * @replacedby: is set to the profile that replaced this profile 150 * @rename: optional profile name that this profile renamed 151 * @xmatch: optional extended matching for unconfined executables names 152 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 153 * @audit: the auditing mode of the profile 154 * @mode: the enforcement mode of the profile 155 * @flags: flags controlling profile behavior 156 * @path_flags: flags controlling path generation behavior 157 * @size: the memory consumed by this profiles rules 158 * @policy: general match rules governing policy 159 * @file: The set of rules governing basic file access and domain transitions 160 * @caps: capabilities for the profile 161 * @rlimits: rlimits for the profile 162 * 163 * The AppArmor profile contains the basic confinement data. Each profile 164 * has a name, and exists in a namespace. The @name and @exec_match are 165 * used to determine profile attachment against unconfined tasks. All other 166 * attachments are determined by profile X transition rules. 167 * 168 * The @replacedby field is write protected by the profile lock. Reads 169 * are assumed to be atomic, and are done without locking. 170 * 171 * Profiles have a hierarchy where hats and children profiles keep 172 * a reference to their parent. 173 * 174 * Profile names can not begin with a : and can not contain the \0 175 * character. If a profile name begins with / it will be considered when 176 * determining profile attachment on "unconfined" tasks. 177 */ 178 struct aa_profile { 179 struct aa_policy base; 180 struct aa_profile *parent; 181 182 struct aa_namespace *ns; 183 struct aa_profile *replacedby; 184 const char *rename; 185 186 struct aa_dfa *xmatch; 187 int xmatch_len; 188 enum audit_mode audit; 189 enum profile_mode mode; 190 u32 flags; 191 u32 path_flags; 192 int size; 193 194 struct aa_policydb policy; 195 struct aa_file_rules file; 196 struct aa_caps caps; 197 struct aa_rlimit rlimits; 198 }; 199 200 extern struct aa_namespace *root_ns; 201 extern enum profile_mode aa_g_profile_mode; 202 203 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 204 205 bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view); 206 const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child); 207 int aa_alloc_root_ns(void); 208 void aa_free_root_ns(void); 209 void aa_free_namespace_kref(struct kref *kref); 210 211 struct aa_namespace *aa_find_namespace(struct aa_namespace *root, 212 const char *name); 213 214 static inline struct aa_policy *aa_get_common(struct aa_policy *c) 215 { 216 if (c) 217 kref_get(&c->count); 218 219 return c; 220 } 221 222 /** 223 * aa_get_namespace - increment references count on @ns 224 * @ns: namespace to increment reference count of (MAYBE NULL) 225 * 226 * Returns: pointer to @ns, if @ns is NULL returns NULL 227 * Requires: @ns must be held with valid refcount when called 228 */ 229 static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) 230 { 231 if (ns) 232 kref_get(&(ns->base.count)); 233 234 return ns; 235 } 236 237 /** 238 * aa_put_namespace - decrement refcount on @ns 239 * @ns: namespace to put reference of 240 * 241 * Decrement reference count of @ns and if no longer in use free it 242 */ 243 static inline void aa_put_namespace(struct aa_namespace *ns) 244 { 245 if (ns) 246 kref_put(&ns->base.count, aa_free_namespace_kref); 247 } 248 249 struct aa_profile *aa_alloc_profile(const char *name); 250 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); 251 void aa_free_profile_kref(struct kref *kref); 252 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 253 struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); 254 struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name); 255 256 ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace); 257 ssize_t aa_remove_profiles(char *name, size_t size); 258 259 #define PROF_ADD 1 260 #define PROF_REPLACE 0 261 262 #define unconfined(X) ((X)->flags & PFLAG_UNCONFINED) 263 264 /** 265 * aa_newest_version - find the newest version of @profile 266 * @profile: the profile to check for newer versions of (NOT NULL) 267 * 268 * Returns: newest version of @profile, if @profile is the newest version 269 * return @profile. 270 * 271 * NOTE: the profile returned is not refcounted, The refcount on @profile 272 * must be held until the caller decides what to do with the returned newest 273 * version. 274 */ 275 static inline struct aa_profile *aa_newest_version(struct aa_profile *profile) 276 { 277 while (profile->replacedby) 278 profile = profile->replacedby; 279 280 return profile; 281 } 282 283 /** 284 * aa_get_profile - increment refcount on profile @p 285 * @p: profile (MAYBE NULL) 286 * 287 * Returns: pointer to @p if @p is NULL will return NULL 288 * Requires: @p must be held with valid refcount when called 289 */ 290 static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 291 { 292 if (p) 293 kref_get(&(p->base.count)); 294 295 return p; 296 } 297 298 /** 299 * aa_put_profile - decrement refcount on profile @p 300 * @p: profile (MAYBE NULL) 301 */ 302 static inline void aa_put_profile(struct aa_profile *p) 303 { 304 if (p) 305 kref_put(&p->base.count, aa_free_profile_kref); 306 } 307 308 static inline int AUDIT_MODE(struct aa_profile *profile) 309 { 310 if (aa_g_audit != AUDIT_NORMAL) 311 return aa_g_audit; 312 313 return profile->audit; 314 } 315 316 bool aa_may_manage_policy(int op); 317 318 #endif /* __AA_POLICY_H */ 319