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 *profile_mode_names[]; 33 #define APPARMOR_NAMES_MAX_INDEX 3 34 35 #define COMPLAIN_MODE(_profile) \ 36 ((aa_g_profile_mode == APPARMOR_COMPLAIN) || \ 37 ((_profile)->mode == APPARMOR_COMPLAIN)) 38 39 #define KILL_MODE(_profile) \ 40 ((aa_g_profile_mode == APPARMOR_KILL) || \ 41 ((_profile)->mode == 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 * 109 * An aa_namespace defines the set profiles that are searched to determine 110 * which profile to attach to a task. Profiles can not be shared between 111 * aa_namespaces and profile names within a namespace are guaranteed to be 112 * unique. When profiles in separate namespaces have the same name they 113 * are NOT considered to be equivalent. 114 * 115 * Namespaces are hierarchical and only namespaces and profiles below the 116 * current namespace are visible. 117 * 118 * Namespace names must be unique and can not contain the characters :/\0 119 * 120 * FIXME TODO: add vserver support of namespaces (can it all be done in 121 * userspace?) 122 */ 123 struct aa_namespace { 124 struct aa_policy base; 125 struct aa_namespace *parent; 126 rwlock_t lock; 127 struct aa_ns_acct acct; 128 struct aa_profile *unconfined; 129 struct list_head sub_ns; 130 }; 131 132 /* struct aa_profile - basic confinement data 133 * @base - base components of the profile (name, refcount, lists, lock ...) 134 * @parent: parent of profile 135 * @ns: namespace the profile is in 136 * @replacedby: is set to the profile that replaced this profile 137 * @rename: optional profile name that this profile renamed 138 * @xmatch: optional extended matching for unconfined executables names 139 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 140 * @sid: the unique security id number of this profile 141 * @audit: the auditing mode of the profile 142 * @mode: the enforcement mode of the profile 143 * @flags: flags controlling profile behavior 144 * @path_flags: flags controlling path generation behavior 145 * @size: the memory consumed by this profiles rules 146 * @file: The set of rules governing basic file access and domain transitions 147 * @caps: capabilities for the profile 148 * @rlimits: rlimits for the profile 149 * 150 * The AppArmor profile contains the basic confinement data. Each profile 151 * has a name, and exists in a namespace. The @name and @exec_match are 152 * used to determine profile attachment against unconfined tasks. All other 153 * attachments are determined by profile X transition rules. 154 * 155 * The @replacedby field is write protected by the profile lock. Reads 156 * are assumed to be atomic, and are done without locking. 157 * 158 * Profiles have a hierarchy where hats and children profiles keep 159 * a reference to their parent. 160 * 161 * Profile names can not begin with a : and can not contain the \0 162 * character. If a profile name begins with / it will be considered when 163 * determining profile attachment on "unconfined" tasks. 164 */ 165 struct aa_profile { 166 struct aa_policy base; 167 struct aa_profile *parent; 168 169 struct aa_namespace *ns; 170 struct aa_profile *replacedby; 171 const char *rename; 172 173 struct aa_dfa *xmatch; 174 int xmatch_len; 175 u32 sid; 176 enum audit_mode audit; 177 enum profile_mode mode; 178 u32 flags; 179 u32 path_flags; 180 int size; 181 182 struct aa_file_rules file; 183 struct aa_caps caps; 184 struct aa_rlimit rlimits; 185 }; 186 187 extern struct aa_namespace *root_ns; 188 extern enum profile_mode aa_g_profile_mode; 189 190 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 191 192 bool aa_ns_visible(struct aa_namespace *curr, struct aa_namespace *view); 193 const char *aa_ns_name(struct aa_namespace *parent, struct aa_namespace *child); 194 int aa_alloc_root_ns(void); 195 void aa_free_root_ns(void); 196 void aa_free_namespace_kref(struct kref *kref); 197 198 struct aa_namespace *aa_find_namespace(struct aa_namespace *root, 199 const char *name); 200 201 static inline struct aa_policy *aa_get_common(struct aa_policy *c) 202 { 203 if (c) 204 kref_get(&c->count); 205 206 return c; 207 } 208 209 /** 210 * aa_get_namespace - increment references count on @ns 211 * @ns: namespace to increment reference count of (MAYBE NULL) 212 * 213 * Returns: pointer to @ns, if @ns is NULL returns NULL 214 * Requires: @ns must be held with valid refcount when called 215 */ 216 static inline struct aa_namespace *aa_get_namespace(struct aa_namespace *ns) 217 { 218 if (ns) 219 kref_get(&(ns->base.count)); 220 221 return ns; 222 } 223 224 /** 225 * aa_put_namespace - decrement refcount on @ns 226 * @ns: namespace to put reference of 227 * 228 * Decrement reference count of @ns and if no longer in use free it 229 */ 230 static inline void aa_put_namespace(struct aa_namespace *ns) 231 { 232 if (ns) 233 kref_put(&ns->base.count, aa_free_namespace_kref); 234 } 235 236 struct aa_profile *aa_alloc_profile(const char *name); 237 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, int hat); 238 void aa_free_profile_kref(struct kref *kref); 239 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 240 struct aa_profile *aa_lookup_profile(struct aa_namespace *ns, const char *name); 241 struct aa_profile *aa_match_profile(struct aa_namespace *ns, const char *name); 242 243 ssize_t aa_replace_profiles(void *udata, size_t size, bool noreplace); 244 ssize_t aa_remove_profiles(char *name, size_t size); 245 246 #define PROF_ADD 1 247 #define PROF_REPLACE 0 248 249 #define unconfined(X) ((X)->flags & PFLAG_UNCONFINED) 250 251 /** 252 * aa_newest_version - find the newest version of @profile 253 * @profile: the profile to check for newer versions of (NOT NULL) 254 * 255 * Returns: newest version of @profile, if @profile is the newest version 256 * return @profile. 257 * 258 * NOTE: the profile returned is not refcounted, The refcount on @profile 259 * must be held until the caller decides what to do with the returned newest 260 * version. 261 */ 262 static inline struct aa_profile *aa_newest_version(struct aa_profile *profile) 263 { 264 while (profile->replacedby) 265 profile = profile->replacedby; 266 267 return profile; 268 } 269 270 /** 271 * aa_get_profile - increment refcount on profile @p 272 * @p: profile (MAYBE NULL) 273 * 274 * Returns: pointer to @p if @p is NULL will return NULL 275 * Requires: @p must be held with valid refcount when called 276 */ 277 static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 278 { 279 if (p) 280 kref_get(&(p->base.count)); 281 282 return p; 283 } 284 285 /** 286 * aa_put_profile - decrement refcount on profile @p 287 * @p: profile (MAYBE NULL) 288 */ 289 static inline void aa_put_profile(struct aa_profile *p) 290 { 291 if (p) 292 kref_put(&p->base.count, aa_free_profile_kref); 293 } 294 295 static inline int AUDIT_MODE(struct aa_profile *profile) 296 { 297 if (aa_g_audit != AUDIT_NORMAL) 298 return aa_g_audit; 299 300 return profile->audit; 301 } 302 303 bool aa_may_manage_policy(int op); 304 305 #endif /* __AA_POLICY_H */ 306