mac_internal.h revision 192881
1/*- 2 * Copyright (c) 1999-2002, 2006, 2009 Robert N. M. Watson 3 * Copyright (c) 2001 Ilmar S. Habibulin 4 * Copyright (c) 2001-2004 Networks Associates Technology, Inc. 5 * Copyright (c) 2006 nCircle Network Security, Inc. 6 * Copyright (c) 2006 SPARTA, Inc. 7 * Copyright (c) 2009 Apple, Inc. 8 * All rights reserved. 9 * 10 * This software was developed by Robert Watson and Ilmar Habibulin for the 11 * TrustedBSD Project. 12 * 13 * This software was developed for the FreeBSD Project in part by Network 14 * Associates Laboratories, the Security Research Division of Network 15 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), 16 * as part of the DARPA CHATS research program. 17 * 18 * This software was developed by Robert N. M. Watson for the TrustedBSD 19 * Project under contract to nCircle Network Security, Inc. 20 * 21 * This software was enhanced by SPARTA ISSO under SPAWAR contract 22 * N66001-04-C-6019 ("SEFOS"). 23 * 24 * This software was developed at the University of Cambridge Computer 25 * Laboratory with support from a grant from Google, Inc. 26 * 27 * Redistribution and use in source and binary forms, with or without 28 * modification, are permitted provided that the following conditions 29 * are met: 30 * 1. Redistributions of source code must retain the above copyright 31 * notice, this list of conditions and the following disclaimer. 32 * 2. Redistributions in binary form must reproduce the above copyright 33 * notice, this list of conditions and the following disclaimer in the 34 * documentation and/or other materials provided with the distribution. 35 * 36 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 37 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 39 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 40 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 41 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 42 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 43 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 44 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 45 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 46 * SUCH DAMAGE. 47 * 48 * $FreeBSD: head/sys/security/mac/mac_internal.h 192881 2009-05-27 09:41:58Z rwatson $ 49 */ 50 51#ifndef _SECURITY_MAC_MAC_INTERNAL_H_ 52#define _SECURITY_MAC_MAC_INTERNAL_H_ 53 54#ifndef _KERNEL 55#error "no user-serviceable parts inside" 56#endif 57 58#include <sys/lock.h> 59#include <sys/rmlock.h> 60 61/* 62 * MAC Framework sysctl namespace. 63 */ 64#ifdef SYSCTL_DECL 65SYSCTL_DECL(_security_mac); 66#endif /* SYSCTL_DECL */ 67 68/* 69 * MAC Framework SDT DTrace probe namespace, macros for declaring entry 70 * point probes, macros for invoking them. 71 */ 72#ifdef SDT_PROVIDER_DECLARE 73SDT_PROVIDER_DECLARE(mac); /* MAC Framework-level events. */ 74SDT_PROVIDER_DECLARE(mac_framework); /* Entry points to MAC. */ 75 76#define MAC_CHECK_PROBE_DEFINE4(name, arg0, arg1, arg2, arg3) \ 77 SDT_PROBE_DEFINE5(mac_framework, kernel, name, mac_check_err, \ 78 "int", arg0, arg1, arg2, arg3); \ 79 SDT_PROBE_DEFINE5(mac_framework, kernel, name, mac_check_ok, \ 80 "int", arg0, arg1, arg2, arg3); 81 82#define MAC_CHECK_PROBE_DEFINE3(name, arg0, arg1, arg2) \ 83 SDT_PROBE_DEFINE4(mac_framework, kernel, name, mac_check_err, \ 84 "int", arg0, arg1, arg2); \ 85 SDT_PROBE_DEFINE4(mac_framework, kernel, name, mac_check_ok, \ 86 "int", arg0, arg1, arg2); 87 88#define MAC_CHECK_PROBE_DEFINE2(name, arg0, arg1) \ 89 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_check_err, \ 90 "int", arg0, arg1); \ 91 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_check_ok, \ 92 "int", arg0, arg1); 93 94#define MAC_CHECK_PROBE_DEFINE1(name, arg0) \ 95 SDT_PROBE_DEFINE2(mac_framework, kernel, name, mac_check_err, \ 96 "int", arg0); \ 97 SDT_PROBE_DEFINE2(mac_framework, kernel, name, mac_check_ok, \ 98 "int", arg0); 99 100#define MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, arg3) do { \ 101 if (error) { \ 102 SDT_PROBE(mac_framework, kernel, name, mac_check_err, \ 103 error, arg0, arg1, arg2, arg3); \ 104 } else { \ 105 SDT_PROBE(mac_framework, kernel, name, mac_check_ok, \ 106 0, arg0, arg1, arg2, arg3); \ 107 } \ 108} while (0) 109 110#define MAC_CHECK_PROBE3(name, error, arg0, arg1, arg2) \ 111 MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, 0) 112#define MAC_CHECK_PROBE2(name, error, arg0, arg1) \ 113 MAC_CHECK_PROBE3(name, error, arg0, arg1, 0) 114#define MAC_CHECK_PROBE1(name, error, arg0) \ 115 MAC_CHECK_PROBE2(name, error, arg0, 0) 116#endif 117 118#define MAC_GRANT_PROBE_DEFINE2(name, arg0, arg1) \ 119 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_grant_err, \ 120 "int", arg0, arg1); \ 121 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_grant_ok, \ 122 "INT", arg0, arg1); 123 124#define MAC_GRANT_PROBE2(name, error, arg0, arg1) do { \ 125 if (error) { \ 126 SDT_PROBE(mac_framework, kernel, name, mac_grant_err, \ 127 error, arg0, arg1, 0, 0); \ 128 } else { \ 129 SDT_PROBE(mac_framework, kernel, name, mac_grant_ok, \ 130 error, arg0, arg1, 0, 0); \ 131 } \ 132} while (0) 133 134/* 135 * MAC Framework global types and typedefs. 136 */ 137LIST_HEAD(mac_policy_list_head, mac_policy_conf); 138#ifdef MALLOC_DECLARE 139MALLOC_DECLARE(M_MACTEMP); 140#endif 141 142/* 143 * MAC labels -- in-kernel storage format. 144 * 145 * In general, struct label pointers are embedded in kernel data structures 146 * representing objects that may be labeled (and protected). Struct label is 147 * opaque to both kernel services that invoke the MAC Framework and MAC 148 * policy modules. In particular, we do not wish to encode the layout of the 149 * label structure into any ABIs. Historically, the slot array contained 150 * unions of {long, void} but now contains uintptr_t. 151 */ 152#define MAC_MAX_SLOTS 4 153#define MAC_FLAG_INITIALIZED 0x0000001 /* Is initialized for use. */ 154struct label { 155 int l_flags; 156 intptr_t l_perpolicy[MAC_MAX_SLOTS]; 157}; 158 159 160/* 161 * Flags for mac_labeled, a bitmask of object types need across the union of 162 * all policies currently registered with the MAC Framework, used to key 163 * whether or not labels are allocated and constructors for the type are 164 * invoked. 165 */ 166#define MPC_OBJECT_CRED 0x0000000000000001 167#define MPC_OBJECT_PROC 0x0000000000000002 168#define MPC_OBJECT_VNODE 0x0000000000000004 169#define MPC_OBJECT_INPCB 0x0000000000000008 170#define MPC_OBJECT_SOCKET 0x0000000000000010 171#define MPC_OBJECT_DEVFS 0x0000000000000020 172#define MPC_OBJECT_MBUF 0x0000000000000040 173#define MPC_OBJECT_IPQ 0x0000000000000080 174#define MPC_OBJECT_IFNET 0x0000000000000100 175#define MPC_OBJECT_BPFDESC 0x0000000000000200 176#define MPC_OBJECT_PIPE 0x0000000000000400 177#define MPC_OBJECT_MOUNT 0x0000000000000800 178#define MPC_OBJECT_POSIXSEM 0x0000000000001000 179#define MPC_OBJECT_POSIXSHM 0x0000000000002000 180#define MPC_OBJECT_SYSVMSG 0x0000000000004000 181#define MPC_OBJECT_SYSVMSQ 0x0000000000008000 182#define MPC_OBJECT_SYSVSEM 0x0000000000010000 183#define MPC_OBJECT_SYSVSHM 0x0000000000020000 184#define MPC_OBJECT_SYNCACHE 0x0000000000040000 185#define MPC_OBJECT_IP6Q 0x0000000000080000 186 187/* 188 * MAC Framework global variables. 189 */ 190extern struct mac_policy_list_head mac_policy_list; 191extern struct mac_policy_list_head mac_static_policy_list; 192extern uint64_t mac_labeled; 193extern struct mtx mac_ifnet_mtx; 194 195/* 196 * MAC Framework infrastructure functions. 197 */ 198int mac_error_select(int error1, int error2); 199 200void mac_policy_slock_nosleep(struct rm_priotracker *tracker); 201void mac_policy_slock_sleep(void); 202void mac_policy_sunlock_nosleep(struct rm_priotracker *tracker); 203void mac_policy_sunlock_sleep(void); 204 205struct label *mac_labelzone_alloc(int flags); 206void mac_labelzone_free(struct label *label); 207void mac_labelzone_init(void); 208 209void mac_init_label(struct label *label); 210void mac_destroy_label(struct label *label); 211int mac_check_structmac_consistent(struct mac *mac); 212int mac_allocate_slot(void); 213 214#define MAC_IFNET_LOCK(ifp) mtx_lock(&mac_ifnet_mtx) 215#define MAC_IFNET_UNLOCK(ifp) mtx_unlock(&mac_ifnet_mtx) 216 217/* 218 * MAC Framework per-object type functions. It's not yet clear how the 219 * namespaces, etc, should work for these, so for now, sort by object type. 220 */ 221struct label *mac_cred_label_alloc(void); 222void mac_cred_label_free(struct label *label); 223struct label *mac_pipe_label_alloc(void); 224void mac_pipe_label_free(struct label *label); 225struct label *mac_socket_label_alloc(int flag); 226void mac_socket_label_free(struct label *label); 227struct label *mac_vnode_label_alloc(void); 228void mac_vnode_label_free(struct label *label); 229 230int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 231int mac_cred_externalize_label(struct label *label, char *elements, 232 char *outbuf, size_t outbuflen); 233int mac_cred_internalize_label(struct label *label, char *string); 234void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 235 236struct label *mac_mbuf_to_label(struct mbuf *m); 237 238void mac_pipe_copy_label(struct label *src, struct label *dest); 239int mac_pipe_externalize_label(struct label *label, char *elements, 240 char *outbuf, size_t outbuflen); 241int mac_pipe_internalize_label(struct label *label, char *string); 242 243int mac_socket_label_set(struct ucred *cred, struct socket *so, 244 struct label *label); 245void mac_socket_copy_label(struct label *src, struct label *dest); 246int mac_socket_externalize_label(struct label *label, char *elements, 247 char *outbuf, size_t outbuflen); 248int mac_socket_internalize_label(struct label *label, char *string); 249 250int mac_vnode_externalize_label(struct label *label, char *elements, 251 char *outbuf, size_t outbuflen); 252int mac_vnode_internalize_label(struct label *label, char *string); 253void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 254 int *prot); 255int vn_setlabel(struct vnode *vp, struct label *intlabel, 256 struct ucred *cred); 257 258/* 259 * MAC Framework composition macros invoke all registered MAC policies for a 260 * specific entry point. They come in two forms: one which permits policies 261 * to sleep/block, and another that does not. 262 * 263 * MAC_POLICY_CHECK performs the designated check by walking the policy 264 * module list and checking with each as to how it feels about the request. 265 * Note that it returns its value via 'error' in the scope of the caller. 266 */ 267#define MAC_POLICY_CHECK(check, args...) do { \ 268 struct mac_policy_conf *mpc; \ 269 \ 270 error = 0; \ 271 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 272 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 273 error = mac_error_select( \ 274 mpc->mpc_ops->mpo_ ## check (args), \ 275 error); \ 276 } \ 277 if (!LIST_EMPTY(&mac_policy_list)) { \ 278 mac_policy_slock_sleep(); \ 279 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 280 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 281 error = mac_error_select( \ 282 mpc->mpc_ops->mpo_ ## check (args), \ 283 error); \ 284 } \ 285 mac_policy_sunlock_sleep(); \ 286 } \ 287} while (0) 288 289#define MAC_POLICY_CHECK_NOSLEEP(check, args...) do { \ 290 struct mac_policy_conf *mpc; \ 291 \ 292 error = 0; \ 293 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 294 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 295 error = mac_error_select( \ 296 mpc->mpc_ops->mpo_ ## check (args), \ 297 error); \ 298 } \ 299 if (!LIST_EMPTY(&mac_policy_list)) { \ 300 struct rm_priotracker tracker; \ 301 \ 302 mac_policy_slock_nosleep(&tracker); \ 303 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 304 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 305 error = mac_error_select( \ 306 mpc->mpc_ops->mpo_ ## check (args), \ 307 error); \ 308 } \ 309 mac_policy_sunlock_nosleep(&tracker); \ 310 } \ 311} while (0) 312 313/* 314 * MAC_POLICY_GRANT performs the designated check by walking the policy 315 * module list and checking with each as to how it feels about the request. 316 * Unlike MAC_POLICY_CHECK, it grants if any policies return '0', and 317 * otherwise returns EPERM. Note that it returns its value via 'error' in 318 * the scope of the caller. 319 */ 320#define MAC_POLICY_GRANT_NOSLEEP(check, args...) do { \ 321 struct mac_policy_conf *mpc; \ 322 \ 323 error = EPERM; \ 324 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 325 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 326 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 327 error = 0; \ 328 } \ 329 } \ 330 if (!LIST_EMPTY(&mac_policy_list)) { \ 331 struct rm_priotracker tracker; \ 332 \ 333 mac_policy_slock_nosleep(&tracker); \ 334 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 335 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 336 if (mpc->mpc_ops->mpo_ ## check (args) \ 337 == 0) \ 338 error = 0; \ 339 } \ 340 } \ 341 mac_policy_sunlock_nosleep(&tracker); \ 342 } \ 343} while (0) 344 345/* 346 * MAC_POLICY_BOOLEAN performs the designated boolean composition by walking 347 * the module list, invoking each instance of the operation, and combining 348 * the results using the passed C operator. Note that it returns its value 349 * via 'result' in the scope of the caller, which should be initialized by 350 * the caller in a meaningful way to get a meaningful result. 351 */ 352#define MAC_POLICY_BOOLEAN(operation, composition, args...) do { \ 353 struct mac_policy_conf *mpc; \ 354 \ 355 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 356 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 357 result = result composition \ 358 mpc->mpc_ops->mpo_ ## operation (args); \ 359 } \ 360 if (!LIST_EMPTY(&mac_policy_list)) { \ 361 mac_policy_slock_sleep(); \ 362 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 363 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 364 result = result composition \ 365 mpc->mpc_ops->mpo_ ## operation \ 366 (args); \ 367 } \ 368 mac_policy_sunlock_sleep(); \ 369 } \ 370} while (0) 371 372#define MAC_POLICY_BOOLEAN_NOSLEEP(operation, composition, args...) do {\ 373 struct mac_policy_conf *mpc; \ 374 \ 375 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 376 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 377 result = result composition \ 378 mpc->mpc_ops->mpo_ ## operation (args); \ 379 } \ 380 if (!LIST_EMPTY(&mac_policy_list)) { \ 381 struct rm_priotracker tracker; \ 382 \ 383 mac_policy_slock_nosleep(&tracker); \ 384 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 385 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 386 result = result composition \ 387 mpc->mpc_ops->mpo_ ## operation \ 388 (args); \ 389 } \ 390 mac_policy_sunlock_nosleep(&tracker); \ 391 } \ 392} while (0) 393 394/* 395 * MAC_POLICY_EXTERNALIZE queries each policy to see if it can generate an 396 * externalized version of a label element by name. Policies declare whether 397 * they have matched a particular element name, parsed from the string by 398 * MAC_POLICY_EXTERNALIZE, and an error is returned if any element is matched 399 * by no policy. 400 */ 401#define MAC_POLICY_EXTERNALIZE(type, label, elementlist, outbuf, \ 402 outbuflen) do { \ 403 int claimed, first, ignorenotfound, savedlen; \ 404 char *element_name, *element_temp; \ 405 struct sbuf sb; \ 406 \ 407 error = 0; \ 408 first = 1; \ 409 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 410 element_temp = elementlist; \ 411 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 412 if (element_name[0] == '?') { \ 413 element_name++; \ 414 ignorenotfound = 1; \ 415 } else \ 416 ignorenotfound = 0; \ 417 savedlen = sbuf_len(&sb); \ 418 if (first) \ 419 error = sbuf_printf(&sb, "%s/", element_name); \ 420 else \ 421 error = sbuf_printf(&sb, ",%s/", element_name); \ 422 if (error == -1) { \ 423 error = EINVAL; /* XXX: E2BIG? */ \ 424 break; \ 425 } \ 426 claimed = 0; \ 427 MAC_POLICY_CHECK(type ## _externalize_label, label, \ 428 element_name, &sb, &claimed); \ 429 if (error) \ 430 break; \ 431 if (claimed == 0 && ignorenotfound) { \ 432 /* Revert last label name. */ \ 433 sbuf_setpos(&sb, savedlen); \ 434 } else if (claimed != 1) { \ 435 error = EINVAL; /* XXX: ENOLABEL? */ \ 436 break; \ 437 } else { \ 438 first = 0; \ 439 } \ 440 } \ 441 sbuf_finish(&sb); \ 442} while (0) 443 444/* 445 * MAC_POLICY_INTERNALIZE presents parsed element names and data to each 446 * policy to see if any is willing to claim it and internalize the label 447 * data. If no policies match, an error is returned. 448 */ 449#define MAC_POLICY_INTERNALIZE(type, label, instring) do { \ 450 char *element, *element_name, *element_data; \ 451 int claimed; \ 452 \ 453 error = 0; \ 454 element = instring; \ 455 while ((element_name = strsep(&element, ",")) != NULL) { \ 456 element_data = element_name; \ 457 element_name = strsep(&element_data, "/"); \ 458 if (element_data == NULL) { \ 459 error = EINVAL; \ 460 break; \ 461 } \ 462 claimed = 0; \ 463 MAC_POLICY_CHECK(type ## _internalize_label, label, \ 464 element_name, element_data, &claimed); \ 465 if (error) \ 466 break; \ 467 if (claimed != 1) { \ 468 /* XXXMAC: Another error here? */ \ 469 error = EINVAL; \ 470 break; \ 471 } \ 472 } \ 473} while (0) 474 475/* 476 * MAC_POLICY_PERFORM performs the designated operation by walking the policy 477 * module list and invoking that operation for each policy. 478 */ 479#define MAC_POLICY_PERFORM(operation, args...) do { \ 480 struct mac_policy_conf *mpc; \ 481 \ 482 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 483 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 484 mpc->mpc_ops->mpo_ ## operation (args); \ 485 } \ 486 if (!LIST_EMPTY(&mac_policy_list)) { \ 487 mac_policy_slock_sleep(); \ 488 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 489 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 490 mpc->mpc_ops->mpo_ ## operation (args); \ 491 } \ 492 mac_policy_sunlock_sleep(); \ 493 } \ 494} while (0) 495 496#define MAC_POLICY_PERFORM_NOSLEEP(operation, args...) do { \ 497 struct mac_policy_conf *mpc; \ 498 \ 499 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 500 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 501 mpc->mpc_ops->mpo_ ## operation (args); \ 502 } \ 503 if (!LIST_EMPTY(&mac_policy_list)) { \ 504 struct rm_priotracker tracker; \ 505 \ 506 mac_policy_slock_nosleep(&tracker); \ 507 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 508 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 509 mpc->mpc_ops->mpo_ ## operation (args); \ 510 } \ 511 mac_policy_sunlock_nosleep(&tracker); \ 512 } \ 513} while (0) 514 515#endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 516