security/apparmor/include/policy.h

   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 "label.h"
  33 #include "net.h"
  34 #include "perms.h"
  35 #include "resource.h"
  36
  37
  38 struct aa_ns;
  39
  40 extern int unprivileged_userns_apparmor_policy;
  41
  42 extern const char *const aa_profile_mode_names[];
  43 #define APPARMOR_MODE_NAMES_MAX_INDEX 4
  44
  45 #define PROFILE_MODE(_profile, _mode)           \
  46         ((aa_g_profile_mode == (_mode)) ||      \
  47          ((_profile)->mode == (_mode)))
  48
  49 #define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
  50
  51 #define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
  52
  53 #define PROFILE_IS_HAT(_profile) ((_profile)->label.flags & FLAG_HAT)
  54
  55 #define profile_is_stale(_profile) (label_is_stale(&(_profile)->label))
  56
  57 #define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
  58
  59 /*
  60  * FIXME: currently need a clean way to replace and remove profiles as a
  61  * set.  It should be done at the namespace level.
  62  * Either, with a set of profiles loaded at the namespace level or via
  63  * a mark and remove marked interface.
  64  */
  65 enum profile_mode {
  66         APPARMOR_ENFORCE,       /* enforce access rules */
  67         APPARMOR_COMPLAIN,      /* allow and log access violations */
  68         APPARMOR_KILL,          /* kill task on access violation */
  69         APPARMOR_UNCONFINED,    /* profile set to unconfined */
  70 };
  71
  72
  73 /* struct aa_policydb - match engine for a policy
  74  * dfa: dfa pattern match
  75  * start: set of start states for the different classes of data
  76  */
  77 struct aa_policydb {
  78         /* Generic policy DFA specific rule types will be subsections of it */
  79         struct aa_dfa *dfa;
  80         unsigned int start[AA_CLASS_LAST + 1];
  81
  82 };
  83
  84 /* struct aa_data - generic data structure
  85  * key: name for retrieving this data
  86  * size: size of data in bytes
  87  * data: binary data
  88  * head: reserved for rhashtable
  89  */
  90 struct aa_data {
  91         char *key;
  92         u32 size;
  93         char *data;
  94         struct rhash_head head;
  95 };
  96
  97
  98 /* struct aa_profile - basic confinement data
  99  * @base - base components of the profile (name, refcount, lists, lock ...)
 100  * @label - label this profile is an extension of
 101  * @parent: parent of profile
 102  * @ns: namespace the profile is in
 103  * @rename: optional profile name that this profile renamed
 104  * @attach: human readable attachment string
 105  * @xmatch: optional extended matching for unconfined executables names
 106  * @xmatch_len: xmatch prefix len, used to determine xmatch priority
 107  * @audit: the auditing mode of the profile
 108  * @mode: the enforcement mode of the profile
 109  * @path_flags: flags controlling path generation behavior
 110  * @disconnected: what to prepend if attach_disconnected is specified
 111  * @size: the memory consumed by this profiles rules
 112  * @policy: general match rules governing policy
 113  * @file: The set of rules governing basic file access and domain transitions
 114  * @caps: capabilities for the profile
 115  * @net: network controls for the profile
 116  * @rlimits: rlimits for the profile
 117  *
 118  * @dents: dentries for the profiles file entries in apparmorfs
 119  * @dirname: name of the profile dir in apparmorfs
 120  * @data: hashtable for free-form policy aa_data
 121  *
 122  * The AppArmor profile contains the basic confinement data.  Each profile
 123  * has a name, and exists in a namespace.  The @name and @exec_match are
 124  * used to determine profile attachment against unconfined tasks.  All other
 125  * attachments are determined by profile X transition rules.
 126  *
 127  * Profiles have a hierarchy where hats and children profiles keep
 128  * a reference to their parent.
 129  *
 130  * Profile names can not begin with a : and can not contain the \0
 131  * character.  If a profile name begins with / it will be considered when
 132  * determining profile attachment on "unconfined" tasks.
 133  */
 134 struct aa_profile {
 135         struct aa_policy base;
 136         struct aa_profile __rcu *parent;
 137
 138         struct aa_ns *ns;
 139         const char *rename;
 140
 141         const char *attach;
 142         struct aa_dfa *xmatch;
 143         int xmatch_len;
 144         enum audit_mode audit;
 145         long mode;
 146         u32 path_flags;
 147         const char *disconnected;
 148         int size;
 149
 150         struct aa_policydb policy;
 151         struct aa_file_rules file;
 152         struct aa_caps caps;
 153         struct aa_net net;
 154         struct aa_rlimit rlimits;
 155
 156         struct aa_loaddata *rawdata;
 157         unsigned char *hash;
 158         char *dirname;
 159         struct dentry *dents[AAFS_PROF_SIZEOF];
 160         struct rhashtable *data;
 161         struct aa_label label;
 162 };
 163
 164 extern enum profile_mode aa_g_profile_mode;
 165
 166 #define AA_MAY_LOAD_POLICY      AA_MAY_APPEND
 167 #define AA_MAY_REPLACE_POLICY   AA_MAY_WRITE
 168 #define AA_MAY_REMOVE_POLICY    AA_MAY_DELETE
 169
 170 #define profiles_ns(P) ((P)->ns)
 171 #define name_is_shared(A, B) ((A)->hname && (A)->hname == (B)->hname)
 172
 173 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
 174
 175
 176 void aa_free_proxy_kref(struct kref *kref);
 177 struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
 178                                     gfp_t gfp);
 179 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
 180                                        const char *base, gfp_t gfp);
 181 void aa_free_profile(struct aa_profile *profile);
 182 void aa_free_profile_kref(struct kref *kref);
 183 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
 184 struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
 185                                       size_t n);
 186 struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name);
 187 struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
 188                                         const char *fqname, size_t n);
 189 struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
 190
 191 ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
 192                             u32 mask, struct aa_loaddata *udata);
 193 ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
 194                            char *name, size_t size);
 195 void __aa_profile_list_release(struct list_head *head);
 196
 197 #define PROF_ADD 1
 198 #define PROF_REPLACE 0
 199
 200 #define profile_unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
 201
 202 /**
 203  * aa_get_newest_profile - simple wrapper fn to wrap the label version
 204  * @p: profile (NOT NULL)
 205  *
 206  * Returns refcount to newest version of the profile (maybe @p)
 207  *
 208  * Requires: @p must be held with a valid refcount
 209  */
 210 static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
 211 {
 212         return labels_profile(aa_get_newest_label(&p->label));
 213 }
 214
 215 #define PROFILE_MEDIATES(P, T)  ((P)->policy.start[(T)])
 216 /* safe version of POLICY_MEDIATES for full range input */
 217 static inline unsigned int PROFILE_MEDIATES_SAFE(struct aa_profile *profile,
 218                                                  unsigned char class)
 219 {
 220         if (profile->policy.dfa)
 221                 return aa_dfa_match_len(profile->policy.dfa,
 222                                         profile->policy.start[0], &class, 1);
 223         return 0;
 224 }
 225
 226 static inline unsigned int PROFILE_MEDIATES_AF(struct aa_profile *profile,
 227                                                u16 AF) {
 228         unsigned int state = PROFILE_MEDIATES(profile, AA_CLASS_NET);
 229         u16 be_af = cpu_to_be16(AF);
 230
 231         if (!state)
 232                 return 0;
 233         return aa_dfa_match_len(profile->policy.dfa, state, (char *) &be_af, 2);
 234 }
 235
 236 /**
 237  * aa_get_profile - increment refcount on profile @p
 238  * @p: profile  (MAYBE NULL)
 239  *
 240  * Returns: pointer to @p if @p is NULL will return NULL
 241  * Requires: @p must be held with valid refcount when called
 242  */
 243 static inline struct aa_profile *aa_get_profile(struct aa_profile *p)
 244 {
 245         if (p)
 246                 kref_get(&(p->label.count));
 247
 248         return p;
 249 }
 250
 251 /**
 252  * aa_get_profile_not0 - increment refcount on profile @p found via lookup
 253  * @p: profile  (MAYBE NULL)
 254  *
 255  * Returns: pointer to @p if @p is NULL will return NULL
 256  * Requires: @p must be held with valid refcount when called
 257  */
 258 static inline struct aa_profile *aa_get_profile_not0(struct aa_profile *p)
 259 {
 260         if (p && kref_get_unless_zero(&p->label.count))
 261                 return p;
 262
 263         return NULL;
 264 }
 265
 266 /**
 267  * aa_get_profile_rcu - increment a refcount profile that can be replaced
 268  * @p: pointer to profile that can be replaced (NOT NULL)
 269  *
 270  * Returns: pointer to a refcounted profile.
 271  *     else NULL if no profile
 272  */
 273 static inline struct aa_profile *aa_get_profile_rcu(struct aa_profile __rcu **p)
 274 {
 275         struct aa_profile *c;
 276
 277         rcu_read_lock();
 278         do {
 279                 c = rcu_dereference(*p);
 280         } while (c && !kref_get_unless_zero(&c->label.count));
 281         rcu_read_unlock();
 282
 283         return c;
 284 }
 285
 286 /**
 287  * aa_put_profile - decrement refcount on profile @p
 288  * @p: profile  (MAYBE NULL)
 289  */
 290 static inline void aa_put_profile(struct aa_profile *p)
 291 {
 292         if (p)
 293                 kref_put(&p->label.count, aa_label_kref);
 294 }
 295
 296 static inline int AUDIT_MODE(struct aa_profile *profile)
 297 {
 298         if (aa_g_audit != AUDIT_NORMAL)
 299                 return aa_g_audit;
 300
 301         return profile->audit;
 302 }
 303
 304 bool policy_view_capable(struct aa_ns *ns);
 305 bool policy_admin_capable(struct aa_ns *ns);
 306 int aa_may_manage_policy(struct aa_label *label, struct aa_ns *ns,
 307                          u32 mask);
 308
 309 #endif /* __AA_POLICY_H */