security/apparmor/include/policy.h

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2 /*
   3  * AppArmor security module
   4  *
   5  * This file contains AppArmor policy definitions.
   6  *
   7  * Copyright (C) 1998-2008 Novell/SUSE
   8  * Copyright 2009-2010 Canonical Ltd.
   9  */
  10
  11 #ifndef __AA_POLICY_H
  12 #define __AA_POLICY_H
  13
  14 #include <linux/capability.h>
  15 #include <linux/cred.h>
  16 #include <linux/kref.h>
  17 #include <linux/rhashtable.h>
  18 #include <linux/sched.h>
  19 #include <linux/slab.h>
  20 #include <linux/socket.h>
  21
  22 #include "apparmor.h"
  23 #include "audit.h"
  24 #include "capability.h"
  25 #include "domain.h"
  26 #include "file.h"
  27 #include "lib.h"
  28 #include "label.h"
  29 #include "net.h"
  30 #include "perms.h"
  31 #include "resource.h"
  32
  33
  34 struct aa_ns;
  35
  36 extern int unprivileged_userns_apparmor_policy;
  37
  38 extern const char *const aa_profile_mode_names[];
  39 #define APPARMOR_MODE_NAMES_MAX_INDEX 4
  40
  41 #define PROFILE_MODE(_profile, _mode)           \
  42         ((aa_g_profile_mode == (_mode)) ||      \
  43          ((_profile)->mode == (_mode)))
  44
  45 #define COMPLAIN_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_COMPLAIN)
  46
  47 #define KILL_MODE(_profile) PROFILE_MODE((_profile), APPARMOR_KILL)
  48
  49 #define PROFILE_IS_HAT(_profile) ((_profile)->label.flags & FLAG_HAT)
  50
  51 #define profile_is_stale(_profile) (label_is_stale(&(_profile)->label))
  52
  53 #define on_list_rcu(X) (!list_empty(X) && (X)->prev != LIST_POISON2)
  54
  55 /*
  56  * FIXME: currently need a clean way to replace and remove profiles as a
  57  * set.  It should be done at the namespace level.
  58  * Either, with a set of profiles loaded at the namespace level or via
  59  * a mark and remove marked interface.
  60  */
  61 enum profile_mode {
  62         APPARMOR_ENFORCE,       /* enforce access rules */
  63         APPARMOR_COMPLAIN,      /* allow and log access violations */
  64         APPARMOR_KILL,          /* kill task on access violation */
  65         APPARMOR_UNCONFINED,    /* profile set to unconfined */
  66 };
  67
  68
  69 /* struct aa_policydb - match engine for a policy
  70  * dfa: dfa pattern match
  71  * start: set of start states for the different classes of data
  72  */
  73 struct aa_policydb {
  74         /* Generic policy DFA specific rule types will be subsections of it */
  75         struct aa_dfa *dfa;
  76         unsigned int start[AA_CLASS_LAST + 1];
  77
  78 };
  79
  80 /* struct aa_data - generic data structure
  81  * key: name for retrieving this data
  82  * size: size of data in bytes
  83  * data: binary data
  84  * head: reserved for rhashtable
  85  */
  86 struct aa_data {
  87         char *key;
  88         u32 size;
  89         char *data;
  90         struct rhash_head head;
  91 };
  92
  93
  94 /* struct aa_profile - basic confinement data
  95  * @base - base components of the profile (name, refcount, lists, lock ...)
  96  * @label - label this profile is an extension of
  97  * @parent: parent of profile
  98  * @ns: namespace the profile is in
  99  * @rename: optional profile name that this profile renamed
 100  * @attach: human readable attachment string
 101  * @xmatch: optional extended matching for unconfined executables names
 102  * @xmatch_len: xmatch prefix len, used to determine xmatch priority
 103  * @audit: the auditing mode of the profile
 104  * @mode: the enforcement mode of the profile
 105  * @path_flags: flags controlling path generation behavior
 106  * @disconnected: what to prepend if attach_disconnected is specified
 107  * @size: the memory consumed by this profiles rules
 108  * @policy: general match rules governing policy
 109  * @file: The set of rules governing basic file access and domain transitions
 110  * @caps: capabilities for the profile
 111  * @rlimits: rlimits for the profile
 112  *
 113  * @dents: dentries for the profiles file entries in apparmorfs
 114  * @dirname: name of the profile dir in apparmorfs
 115  * @data: hashtable for free-form policy aa_data
 116  *
 117  * The AppArmor profile contains the basic confinement data.  Each profile
 118  * has a name, and exists in a namespace.  The @name and @exec_match are
 119  * used to determine profile attachment against unconfined tasks.  All other
 120  * attachments are determined by profile X transition rules.
 121  *
 122  * Profiles have a hierarchy where hats and children profiles keep
 123  * a reference to their parent.
 124  *
 125  * Profile names can not begin with a : and can not contain the \0
 126  * character.  If a profile name begins with / it will be considered when
 127  * determining profile attachment on "unconfined" tasks.
 128  */
 129 struct aa_profile {
 130         struct aa_policy base;
 131         struct aa_profile __rcu *parent;
 132
 133         struct aa_ns *ns;
 134         const char *rename;
 135
 136         const char *attach;
 137         struct aa_dfa *xmatch;
 138         int xmatch_len;
 139         enum audit_mode audit;
 140         long mode;
 141         u32 path_flags;
 142         const char *disconnected;
 143         int size;
 144
 145         struct aa_policydb policy;
 146         struct aa_file_rules file;
 147         struct aa_caps caps;
 148
 149         int xattr_count;
 150         char **xattrs;
 151
 152         struct aa_rlimit rlimits;
 153
 154         int secmark_count;
 155         struct aa_secmark *secmark;
 156
 157         struct aa_loaddata *rawdata;
 158         unsigned char *hash;
 159         char *dirname;
 160         struct dentry *dents[AAFS_PROF_SIZEOF];
 161         struct rhashtable *data;
 162         struct aa_label label;
 163 };
 164
 165 extern enum profile_mode aa_g_profile_mode;
 166
 167 #define AA_MAY_LOAD_POLICY      AA_MAY_APPEND
 168 #define AA_MAY_REPLACE_POLICY   AA_MAY_WRITE
 169 #define AA_MAY_REMOVE_POLICY    AA_MAY_DELETE
 170
 171 #define profiles_ns(P) ((P)->ns)
 172 #define name_is_shared(A, B) ((A)->hname && (A)->hname == (B)->hname)
 173
 174 void aa_add_profile(struct aa_policy *common, struct aa_profile *profile);
 175
 176
 177 void aa_free_proxy_kref(struct kref *kref);
 178 struct aa_profile *aa_alloc_profile(const char *name, struct aa_proxy *proxy,
 179                                     gfp_t gfp);
 180 struct aa_profile *aa_new_null_profile(struct aa_profile *parent, bool hat,
 181                                        const char *base, gfp_t gfp);
 182 void aa_free_profile(struct aa_profile *profile);
 183 void aa_free_profile_kref(struct kref *kref);
 184 struct aa_profile *aa_find_child(struct aa_profile *parent, const char *name);
 185 struct aa_profile *aa_lookupn_profile(struct aa_ns *ns, const char *hname,
 186                                       size_t n);
 187 struct aa_profile *aa_lookup_profile(struct aa_ns *ns, const char *name);
 188 struct aa_profile *aa_fqlookupn_profile(struct aa_label *base,
 189                                         const char *fqname, size_t n);
 190 struct aa_profile *aa_match_profile(struct aa_ns *ns, const char *name);
 191
 192 ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_label *label,
 193                             u32 mask, struct aa_loaddata *udata);
 194 ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_label *label,
 195                            char *name, size_t size);
 196 void __aa_profile_list_release(struct list_head *head);
 197
 198 #define PROF_ADD 1
 199 #define PROF_REPLACE 0
 200
 201 #define profile_unconfined(X) ((X)->mode == APPARMOR_UNCONFINED)
 202
 203 /**
 204  * aa_get_newest_profile - simple wrapper fn to wrap the label version
 205  * @p: profile (NOT NULL)
 206  *
 207  * Returns refcount to newest version of the profile (maybe @p)
 208  *
 209  * Requires: @p must be held with a valid refcount
 210  */
 211 static inline struct aa_profile *aa_get_newest_profile(struct aa_profile *p)
 212 {
 213         return labels_profile(aa_get_newest_label(&p->label));
 214 }
 215
 216 static inline unsigned int PROFILE_MEDIATES(struct aa_profile *profile,
 217                                             unsigned char class)
 218 {
 219         if (class <= AA_CLASS_LAST)
 220                 return profile->policy.start[class];
 221         else
 222                 return aa_dfa_match_len(profile->policy.dfa,
 223                                         profile->policy.start[0], &class, 1);
 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         __be16 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 */