security/mac_internal.h

   1 /*
   2  * Copyright (c) 2007 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 /*-
  30  * Copyright (c) 1999, 2000, 2001, 2002 Robert N. M. Watson
  31  * Copyright (c) 2001 Ilmar S. Habibulin
  32  * Copyright (c) 2001, 2002, 2003, 2004 Networks Associates Technology, Inc.
  33  * Copyright (c) 2005 SPARTA, Inc.
  34  * All rights reserved.
  35  *
  36  * This software was developed by Robert Watson and Ilmar Habibulin for the
  37  * TrustedBSD Project.
  38  *
  39  * This software was developed for the FreeBSD Project in part by Network
  40  * Associates Laboratories, the Security Research Division of Network
  41  * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"),
  42  * as part of the DARPA CHATS research program.
  43  *
  44  * Redistribution and use in source and binary forms, with or without
  45  * modification, are permitted provided that the following conditions
  46  * are met:
  47  * 1. Redistributions of source code must retain the above copyright
  48  *    notice, this list of conditions and the following disclaimer.
  49  * 2. Redistributions in binary form must reproduce the above copyright
  50  *    notice, this list of conditions and the following disclaimer in the
  51  *    documentation and/or other materials provided with the distribution.
  52  *
  53  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  54  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  55  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  56  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  57  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  58  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  59  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  60  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  61  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  62  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  63  * SUCH DAMAGE.
  64  *
  65  */
  66
  67 #ifndef _SECURITY_MAC_INTERNAL_H_
  68 #define _SECURITY_MAC_INTERNAL_H_
  69
  70 #ifndef PRIVATE
  71 #warning "MAC policy is not KPI, see Technical Q&A QA1574, this header will be removed in next version"
  72 #endif
  73
  74 #include <string.h>
  75 #include <sys/param.h>
  76 #include <sys/queue.h>
  77 #include <security/mac.h>
  78 #include <security/mac_framework.h>
  79 #include <security/mac_policy.h>
  80 #include <security/mac_data.h>
  81 #include <sys/sysctl.h>
  82 #include <kern/locks.h>
  83 #include <sys/kernel.h>
  84 #include <sys/lock.h>
  85 #include <sys/malloc.h>
  86 #include <sys/sbuf.h>
  87 #include <sys/proc.h>
  88 #include <sys/systm.h>
  89 #include <sys/socket.h>
  90 #include <sys/socketvar.h>
  91 #include <sys/vnode.h>
  92
  93 /*
  94  * MAC Framework sysctl namespace.
  95  */
  96
  97 SYSCTL_DECL(_security);
  98 SYSCTL_DECL(_security_mac);
  99
 100 extern int mac_late;
 101
 102 struct mac_policy_list_element {
 103         struct mac_policy_conf *mpc;
 104 };
 105
 106 struct mac_policy_list {
 107         u_int                           numloaded;
 108         u_int                           max;
 109         u_int                           maxindex;
 110         u_int                           staticmax;
 111         u_int                           chunks;
 112         u_int                           freehint;
 113         struct mac_policy_list_element  *entries;
 114 };
 115
 116 typedef struct mac_policy_list mac_policy_list_t;
 117
 118
 119 /*
 120  * Policy that has registered with the framework for a specific
 121  * label namespace name.
 122  */
 123 struct mac_label_listener {
 124         mac_policy_handle_t             mll_handle;
 125         LIST_ENTRY(mac_label_listener)  mll_list;
 126 };
 127
 128 LIST_HEAD(mac_label_listeners_t, mac_label_listener);
 129
 130 /*
 131  * Type of list used to manage label namespace names.
 132  */
 133 struct mac_label_element {
 134         char                            mle_name[MAC_MAX_LABEL_ELEMENT_NAME];
 135         struct mac_label_listeners_t    mle_listeners;
 136         LIST_ENTRY(mac_label_element)   mle_list;
 137 };
 138
 139 LIST_HEAD(mac_label_element_list_t, mac_label_element);
 140
 141 /*
 142  * MAC Framework global variables.
 143  */
 144
 145 extern struct mac_label_element_list_t mac_label_element_list;
 146 extern struct mac_label_element_list_t mac_static_label_element_list;
 147
 148 extern struct mac_policy_list mac_policy_list;
 149
 150 /*
 151  * global flags to control whether a MACF subsystem is configured
 152  * at all in the system.
 153  */
 154 extern unsigned int mac_device_enforce;
 155 extern unsigned int mac_pipe_enforce;
 156 extern unsigned int mac_posixsem_enforce;
 157 extern unsigned int mac_posixshm_enforce;
 158 extern unsigned int mac_proc_enforce;
 159 extern unsigned int mac_socket_enforce;
 160 extern unsigned int mac_system_enforce;
 161 extern unsigned int mac_sysvmsg_enforce;
 162 extern unsigned int mac_sysvsem_enforce;
 163 extern unsigned int mac_sysvshm_enforce;
 164 extern unsigned int mac_vm_enforce;
 165 extern unsigned int mac_vnode_enforce;
 166
 167 extern unsigned int mac_label_vnodes;
 168 extern unsigned int mac_vnode_label_count;
 169
 170 static bool mac_proc_check_enforce(proc_t p);
 171
 172 static __inline__ bool
 173 mac_proc_check_enforce(proc_t p)
 174 {
 175 #if CONFIG_MACF
 176         // Don't apply policies to the kernel itself.
 177         return p != kernproc;
 178 #else
 179 #pragma unused(p)
 180         return false;
 181 #endif // CONFIG_MACF
 182 }
 183
 184 static bool mac_cred_check_enforce(kauth_cred_t cred);
 185
 186 static __inline__ bool
 187 mac_cred_check_enforce(kauth_cred_t cred)
 188 {
 189 #if CONFIG_MACF
 190         return cred != proc_ucred(kernproc);
 191 #else
 192 #pragma unused(p)
 193         return false;
 194 #endif // CONFIG_MACF
 195 }
 196
 197 /*
 198  * MAC Framework infrastructure functions.
 199  */
 200
 201 int mac_error_select(int error1, int error2);
 202
 203 void  mac_policy_list_busy(void);
 204 int   mac_policy_list_conditional_busy(void);
 205 void  mac_policy_list_unbusy(void);
 206
 207 void           mac_labelzone_init(void);
 208 struct label  *mac_labelzone_alloc(int flags);
 209 void           mac_labelzone_free(struct label *label);
 210
 211 void  mac_label_init(struct label *label);
 212 void  mac_label_destroy(struct label *label);
 213 #if KERNEL
 214 int   mac_check_structmac_consistent(struct user_mac *mac);
 215 #else
 216 int   mac_check_structmac_consistent(struct mac *mac);
 217 #endif
 218
 219 int mac_cred_label_externalize(struct label *, char *e, char *out, size_t olen, int flags);
 220 int mac_vnode_label_externalize(struct label *, char *e, char *out, size_t olen, int flags);
 221
 222 int mac_cred_label_internalize(struct label *label, char *string);
 223 int mac_vnode_label_internalize(struct label *label, char *string);
 224
 225 /*
 226  * MAC_CHECK performs the designated check by walking the policy
 227  * module list and checking with each as to how it feels about the
 228  * request.  Note that it returns its value via 'error' in the scope
 229  * of the caller.
 230  */
 231 #define MAC_CHECK(check, args...) do {                                  \
 232         struct mac_policy_conf *mpc;                                    \
 233         u_int i;                                                        \
 234                                                                         \
 235         error = 0;                                                      \
 236         for (i = 0; i < mac_policy_list.staticmax; i++) {               \
 237                 mpc = mac_policy_list.entries[i].mpc;                   \
 238                 if (mpc == NULL)                                        \
 239                         continue;                                       \
 240                                                                         \
 241                 if (mpc->mpc_ops->mpo_ ## check != NULL)                \
 242                         error = mac_error_select(                       \
 243                             mpc->mpc_ops->mpo_ ## check (args),         \
 244                             error);                                     \
 245         }                                                               \
 246         if (mac_policy_list_conditional_busy() != 0) {                  \
 247                 for (; i <= mac_policy_list.maxindex; i++) {            \
 248                         mpc = mac_policy_list.entries[i].mpc;           \
 249                         if (mpc == NULL)                                \
 250                                 continue;                               \
 251                                                                         \
 252                         if (mpc->mpc_ops->mpo_ ## check != NULL)        \
 253                                 error = mac_error_select(               \
 254                                     mpc->mpc_ops->mpo_ ## check (args), \
 255                                     error);                             \
 256                 }                                                       \
 257                 mac_policy_list_unbusy();                               \
 258         }                                                               \
 259 } while (0)
 260
 261 /*
 262  * MAC_GRANT performs the designated check by walking the policy
 263  * module list and checking with each as to how it feels about the
 264  * request.  Unlike MAC_CHECK, it grants if any policies return '0',
 265  * and otherwise returns EPERM.  Note that it returns its value via
 266  * 'error' in the scope of the caller.
 267  */
 268 #define MAC_GRANT(check, args...) do {                                  \
 269         struct mac_policy_conf *mpc;                                    \
 270         u_int i;                                                        \
 271                                                                         \
 272         error = EPERM;                                                  \
 273         for (i = 0; i < mac_policy_list.staticmax; i++) {               \
 274                 mpc = mac_policy_list.entries[i].mpc;                   \
 275                 if (mpc == NULL)                                        \
 276                         continue;                                       \
 277                                                                         \
 278                 if (mpc->mpc_ops->mpo_ ## check != NULL) {              \
 279                         if (mpc->mpc_ops->mpo_ ## check (args) == 0)    \
 280                                 error = 0;                              \
 281                 }                                                       \
 282         }                                                               \
 283         if (mac_policy_list_conditional_busy() != 0) {                  \
 284                 for (; i <= mac_policy_list.maxindex; i++) {            \
 285                         mpc = mac_policy_list.entries[i].mpc;           \
 286                         if (mpc == NULL)                                \
 287                                 continue;                               \
 288                                                                         \
 289                         if (mpc->mpc_ops->mpo_ ## check != NULL) {      \
 290                                 if (mpc->mpc_ops->mpo_ ## check (args)  \
 291                                     == 0)                               \
 292                                         error = 0;                      \
 293                         }                                               \
 294                 }                                                       \
 295                 mac_policy_list_unbusy();                               \
 296         }                                                               \
 297 } while (0)
 298
 299 /*
 300  * MAC_BOOLEAN performs the designated boolean composition by walking
 301  * the module list, invoking each instance of the operation, and
 302  * combining the results using the passed C operator.  Note that it
 303  * returns its value via 'result' in the scope of the caller, which
 304  * should be initialized by the caller in a meaningful way to get
 305  * a meaningful result.
 306  */
 307 #define MAC_BOOLEAN(operation, composition, args...) do {               \
 308         struct mac_policy_conf *mpc;                                    \
 309         u_int i;                                                        \
 310                                                                         \
 311         for (i = 0; i < mac_policy_list.staticmax; i++) {               \
 312                 mpc = mac_policy_list.entries[i].mpc;                   \
 313                 if (mpc == NULL)                                        \
 314                         continue;                                       \
 315                                                                         \
 316                 if (mpc->mpc_ops->mpo_ ## operation != NULL)            \
 317                         result = result composition                     \
 318                             mpc->mpc_ops->mpo_ ## operation             \
 319                             (args);                                     \
 320         }                                                               \
 321         if (mac_policy_list_conditional_busy() != 0) {                  \
 322                 for (; i <= mac_policy_list.maxindex; i++) {            \
 323                         mpc = mac_policy_list.entries[i].mpc;           \
 324                         if (mpc == NULL)                                \
 325                                 continue;                               \
 326                                                                         \
 327                         if (mpc->mpc_ops->mpo_ ## operation != NULL)    \
 328                                 result = result composition             \
 329                                     mpc->mpc_ops->mpo_ ## operation     \
 330                                     (args);                             \
 331                 }                                                       \
 332                 mac_policy_list_unbusy();                               \
 333         }                                                               \
 334 } while (0)
 335
 336 #define MAC_INTERNALIZE(obj, label, instring)                           \
 337         mac_internalize(offsetof(struct mac_policy_ops, mpo_ ## obj ## _label_internalize), label, instring)
 338
 339 #define MAC_EXTERNALIZE(obj, label, elementlist, outbuf, outbuflen)     \
 340         mac_externalize(offsetof(struct mac_policy_ops, mpo_ ## obj ## _label_externalize), label, elementlist, outbuf, outbuflen)
 341
 342 #define MAC_EXTERNALIZE_AUDIT(obj, label, outbuf, outbuflen)    \
 343         mac_externalize(offsetof(struct mac_policy_ops, mpo_ ## obj ## _label_externalize_audit), label, "*", outbuf, outbuflen)
 344
 345 /*
 346  * MAC_PERFORM performs the designated operation by walking the policy
 347  * module list and invoking that operation for each policy.
 348  */
 349 #define MAC_PERFORM(operation, args...) do {                            \
 350         struct mac_policy_conf *mpc;                                    \
 351         u_int i;                                                        \
 352                                                                         \
 353         for (i = 0; i < mac_policy_list.staticmax; i++) {               \
 354                 mpc = mac_policy_list.entries[i].mpc;                   \
 355                 if (mpc == NULL)                                        \
 356                         continue;                                       \
 357                                                                         \
 358                 if (mpc->mpc_ops->mpo_ ## operation != NULL)            \
 359                         mpc->mpc_ops->mpo_ ## operation (args);         \
 360         }                                                               \
 361         if (mac_policy_list_conditional_busy() != 0) {                  \
 362                 for (; i <= mac_policy_list.maxindex; i++) {            \
 363                         mpc = mac_policy_list.entries[i].mpc;           \
 364                         if (mpc == NULL)                                \
 365                                 continue;                               \
 366                                                                         \
 367                         if (mpc->mpc_ops->mpo_ ## operation != NULL)    \
 368                                 mpc->mpc_ops->mpo_ ## operation (args); \
 369                 }                                                       \
 370                 mac_policy_list_unbusy();                               \
 371         }                                                               \
 372 } while (0)
 373
 374 struct __mac_get_pid_args;
 375 struct __mac_get_proc_args;
 376 struct __mac_set_proc_args;
 377 struct __mac_get_lcid_args;
 378 struct __mac_get_fd_args;
 379 struct __mac_get_file_args;
 380 struct __mac_get_link_args;
 381 struct __mac_set_fd_args;
 382 struct __mac_set_file_args;
 383 struct __mac_syscall_args;
 384
 385 void mac_policy_addto_labellist(const mac_policy_handle_t, int);
 386 void mac_policy_removefrom_labellist(const mac_policy_handle_t);
 387
 388 int mac_externalize(size_t mpo_externalize_off, struct label *label,
 389     const char *elementlist, char *outbuf, size_t outbuflen);
 390 int mac_internalize(size_t mpo_internalize_off, struct label *label,
 391     char *elementlist);
 392 #endif  /* !_SECURITY_MAC_INTERNAL_H_ */