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/rhashtable.h> 22 #include <linux/sched.h> 23 #include <linux/slab.h> 24 #include <linux/socket.h> 25 26 #include "apparmor.h" 27 #include "audit.h" 28 #include "capability.h" 29 #include "domain.h" 30 #include "file.h" 31 #include "lib.h" 32 #include "resource.h" 33 34 35 struct aa_ns; 36 37 extern int unprivileged_userns_apparmor_policy; 38 39 extern const char *const aa_profile_mode_names[]; 40 #define APPARMOR_MODE_NAMES_MAX_INDEX 4 41 42 #define PROFILE_MODE(_profile, _mode) \ 43 ((aa_g_profile_mode == (_mode)) || \ 44 ((_profile)->mode == (_mode))) 45 46 #define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN) 47 48 #define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL) 49 50 #define PROFILE_IS_HAT(_profile) ((_profile)->flags & PFLAG_HAT) 51 52 #define profile_is_stale(_profile) ((_profile)->flags & PFLAG_STALE) 53 54 #define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2) 55 56 /* 57 * FIXME: currently need a clean way to replace and remove profiles as a 58 * set. It should be done at the namespace level. 59 * Either, with a set of profiles loaded at the namespace level or via 60 * a mark and remove marked interface. 61 */ 62 enum profile_mode { 63 APPARMOR_ENFORCE, /* enforce access rules */ 64 APPARMOR_COMPLAIN, /* allow and log access violations */ 65 APPARMOR_KILL, /* kill task on access violation */ 66 APPARMOR_UNCONFINED, /* profile set to unconfined */ 67 }; 68 69 enum profile_flags { 70 PFLAG_HAT = 1, /* profile is a hat */ 71 PFLAG_NULL = 4, /* profile is null learning profile */ 72 PFLAG_IX_ON_NAME_ERROR = 8, /* fallback to ix on name lookup fail */ 73 PFLAG_IMMUTABLE = 0x10, /* don't allow changes/replacement */ 74 PFLAG_USER_DEFINED = 0x20, /* user based profile - lower privs */ 75 PFLAG_NO_LIST_REF = 0x40, /* list doesn't keep profile ref */ 76 PFLAG_OLD_NULL_TRANS = 0x100, /* use // as the null transition */ 77 PFLAG_STALE = 0x200, /* profile replaced/removed */ 78 PFLAG_NS_COUNT = 0x400, /* carries NS ref count */ 79 80 /* These flags must correspond with PATH_flags */ 81 PFLAG_MEDIATE_DELETED = 0x10000, /* mediate instead delegate deleted */ 82 }; 83 84 struct aa_profile; 85 86 /* struct aa_policydb - match engine for a policy 87 * dfa: dfa pattern match 88 * start: set of start states for the different classes of data 89 */ 90 struct aa_policydb { 91 /* Generic policy DFA specific rule types will be subsections of it */ 92 struct aa_dfa *dfa; 93 unsigned int start[AA_CLASS_LAST + 1]; 94 95 }; 96 97 struct aa_proxy { 98 struct kref count; 99 struct aa_profile __rcu *profile; 100 }; 101 102 /* struct aa_data - generic data structure 103 * key: name for retrieving this data 104 * size: size of data in bytes 105 * data: binary data 106 * head: reserved for rhashtable 107 */ 108 struct aa_data { 109 char *key; 110 u32 size; 111 char *data; 112 struct rhash_head head; 113 }; 114 115 116 /* struct aa_profile - basic confinement data 117 * @base - base components of the profile (name, refcount, lists, lock ...) 118 * @count: reference count of the obj 119 * @rcu: rcu head used when removing from @list 120 * @parent: parent of profile 121 * @ns: namespace the profile is in 122 * @proxy: is set to the profile that replaced this profile 123 * @rename: optional profile name that this profile renamed 124 * @attach: human readable attachment string 125 * @xmatch: optional extended matching for unconfined executables names 126 * @xmatch_len: xmatch prefix len, used to determine xmatch priority 127 * @audit: the auditing mode of the profile 128 * @mode: the enforcement mode of the profile 129 * @flags: flags controlling profile behavior 130 * @path_flags: flags controlling path generation behavior 131 * @size: the memory consumed by this profiles rules 132 * @policy: general match rules governing policy 133 * @file: The set of rules governing basic file access and domain transitions 134 * @caps: capabilities for the profile 135 * @rlimits: rlimits for the profile 136 * 137 * @dents: dentries for the profiles file entries in apparmorfs 138 * @dirname: name of the profile dir in apparmorfs 139 * @data: hashtable for free-form policy aa_data 140 * 141 * The AppArmor profile contains the basic confinement data. Each profile 142 * has a name, and exists in a namespace. The @name and @exec_match are 143 * used to determine profile attachment against unconfined tasks. All other 144 * attachments are determined by profile X transition rules. 145 * 146 * The @proxy struct is write protected by the profile lock. 147 * 148 * Profiles have a hierarchy where hats and children profiles keep 149 * a reference to their parent. 150 * 151 * Profile names can not begin with a : and can not contain the \0 152 * character. If a profile name begins with / it will be considered when 153 * determining profile attachment on "unconfined" tasks. 154 */ 155 struct aa_profile { 156 struct aa_policy base; 157 struct kref count; 158 struct rcu_head rcu; 159 struct aa_profile __rcu *parent; 160 161 struct aa_ns *ns; 162 struct aa_proxy *proxy; 163 const char *rename; 164 165 const char *attach; 166 struct aa_dfa *xmatch; 167 int xmatch_len; 168 enum audit_mode audit; 169 long mode; 170 long flags; 171 u32 path_flags; 172 int size; 173 174 struct aa_policydb policy; 175 struct aa_file_rules file; 176 struct aa_caps caps; 177 struct aa_rlimit rlimits; 178 179 struct aa_loaddata *rawdata; 180 unsigned char *hash; 181 char *dirname; 182 struct dentry *dents[AAFS_PROF_SIZEOF]; 183 struct rhashtable *data; 184 }; 185 186 extern enum profile_mode aa_g_profile_mode; 187 188 void __aa_update_proxy(struct aa_profile *orig, struct aa_profile *new); 189 190 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile); 191 192 193 void aa_free_proxy_kref(struct kref *kref); 194 struct aa_profile *aa_alloc_profile(const char *name, gfp_t gfp); 195 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat, 196 const char *base, gfp_t gfp); 197 void aa_free_profile(struct aa_profile *profile); 198 void aa_free_profile_kref(struct kref *kref); 199 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name); 200 struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname, 201 size_t n); 202 struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name); 203 struct aa_profile *aa_fqlookupn_profile(struct aa_profile *base, 204 const char *fqname, size_t n); 205 struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name); 206 207 ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile, 208 bool noreplace, struct aa_loaddata *udata); 209 ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_profile *profile, 210 char *name, size_t size); 211 void __aa_profile_list_release(struct list_head *head); 212 213 #define PROF_ADD 1 214 #define PROF_REPLACE 0 215 216 #define unconfined(X) ((X)->mode == APPARMOR_UNCONFINED) 217 218 219 /** 220 * aa_get_profile - increment refcount on profile @p 221 * @p: profile (MAYBE NULL) 222 * 223 * Returns: pointer to @p if @p is NULL will return NULL 224 * Requires: @p must be held with valid refcount when called 225 */ 226 static inline struct aa_profile *aa_get_profile(struct aa_profile *p) 227 { 228 if (p) 229 kref_get(&(p->count)); 230 231 return p; 232 } 233 234 /** 235 * aa_get_profile_not0 - increment refcount on profile @p found via lookup 236 * @p: profile (MAYBE NULL) 237 * 238 * Returns: pointer to @p if @p is NULL will return NULL 239 * Requires: @p must be held with valid refcount when called 240 */ 241 static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p) 242 { 243 if (p && kref_get_unless_zero(&p->count)) 244 return p; 245 246 return NULL; 247 } 248 249 /** 250 * aa_get_profile_rcu - increment a refcount profile that can be replaced 251 * @p: pointer to profile that can be replaced (NOT NULL) 252 * 253 * Returns: pointer to a refcounted profile. 254 * else NULL if no profile 255 */ 256 static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p) 257 { 258 struct aa_profile *c; 259 260 rcu_read_lock(); 261 do { 262 c = rcu_dereference(*p); 263 } while (c && !kref_get_unless_zero(&c->count)); 264 rcu_read_unlock(); 265 266 return c; 267 } 268 269 /** 270 * aa_get_newest_profile - find the newest version of @profile 271 * @profile: the profile to check for newer versions of 272 * 273 * Returns: refcounted newest version of @profile taking into account 274 * replacement, renames and removals 275 * return @profile. 276 */ 277 static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p) 278 { 279 if (!p) 280 return NULL; 281 282 if (profile_is_stale(p)) 283 return aa_get_profile_rcu(&p->proxy->profile); 284 285 return aa_get_profile(p); 286 } 287 288 /** 289 * aa_put_profile - decrement refcount on profile @p 290 * @p: profile (MAYBE NULL) 291 */ 292 static inline void aa_put_profile(struct aa_profile *p) 293 { 294 if (p) 295 kref_put(&p->count, aa_free_profile_kref); 296 } 297 298 static inline struct aa_proxy *aa_get_proxy(struct aa_proxy *p) 299 { 300 if (p) 301 kref_get(&(p->count)); 302 303 return p; 304 } 305 306 static inline void aa_put_proxy(struct aa_proxy *p) 307 { 308 if (p) 309 kref_put(&p->count, aa_free_proxy_kref); 310 } 311 312 static inline int AUDIT_MODE(struct aa_profile *profile) 313 { 314 if (aa_g_audit != AUDIT_NORMAL) 315 return aa_g_audit; 316 317 return profile->audit; 318 } 319 320 bool policy_view_capable(struct aa_ns *ns); 321 bool policy_admin_capable(struct aa_ns *ns); 322 int aa_may_manage_policy(struct aa_profile *profile, struct aa_ns *ns, 323 const char *op); 324 325 #endif /* __AA_POLICY_H */ 326