mac_internal.h revision 191731
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 191731 2009-05-01 21:05:40Z 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/* 59 * MAC Framework sysctl namespace. 60 */ 61#ifdef SYSCTL_DECL 62SYSCTL_DECL(_security_mac); 63#endif /* SYSCTL_DECL */ 64 65/* 66 * MAC Framework SDT DTrace probe namespace, macros for declaring entry 67 * point probes, macros for invoking them. 68 */ 69#ifdef SDT_PROVIDER_DECLARE 70SDT_PROVIDER_DECLARE(mac); /* MAC Framework-level events. */ 71SDT_PROVIDER_DECLARE(mac_framework); /* Entry points to MAC. */ 72 73#define MAC_CHECK_PROBE_DEFINE4(name, arg0, arg1, arg2, arg3) \ 74 SDT_PROBE_DEFINE5(mac_framework, kernel, name, mac_check_err, \ 75 "int", arg0, arg1, arg2, arg3); \ 76 SDT_PROBE_DEFINE5(mac_framework, kernel, name, mac_check_ok, \ 77 "int", arg0, arg1, arg2, arg3); 78 79#define MAC_CHECK_PROBE_DEFINE3(name, arg0, arg1, arg2) \ 80 SDT_PROBE_DEFINE4(mac_framework, kernel, name, mac_check_err, \ 81 "int", arg0, arg1, arg2); \ 82 SDT_PROBE_DEFINE4(mac_framework, kernel, name, mac_check_ok, \ 83 "int", arg0, arg1, arg2); 84 85#define MAC_CHECK_PROBE_DEFINE2(name, arg0, arg1) \ 86 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_check_err, \ 87 "int", arg0, arg1); \ 88 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_check_ok, \ 89 "int", arg0, arg1); 90 91#define MAC_CHECK_PROBE_DEFINE1(name, arg0) \ 92 SDT_PROBE_DEFINE2(mac_framework, kernel, name, mac_check_err, \ 93 "int", arg0); \ 94 SDT_PROBE_DEFINE2(mac_framework, kernel, name, mac_check_ok, \ 95 "int", arg0); 96 97#define MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, arg3) do { \ 98 if (error) { \ 99 SDT_PROBE(mac_framework, kernel, name, mac_check_err, \ 100 error, arg0, arg1, arg2, arg3); \ 101 } else { \ 102 SDT_PROBE(mac_framework, kernel, name, mac_check_ok, \ 103 0, arg0, arg1, arg2, arg3); \ 104 } \ 105} while (0) 106 107#define MAC_CHECK_PROBE3(name, error, arg0, arg1, arg2) \ 108 MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, 0) 109#define MAC_CHECK_PROBE2(name, error, arg0, arg1) \ 110 MAC_CHECK_PROBE3(name, error, arg0, arg1, 0) 111#define MAC_CHECK_PROBE1(name, error, arg0) \ 112 MAC_CHECK_PROBE2(name, error, arg0, 0) 113#endif 114 115#define MAC_GRANT_PROBE_DEFINE2(name, arg0, arg1) \ 116 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_grant_err, \ 117 "int", arg0, arg1); \ 118 SDT_PROBE_DEFINE3(mac_framework, kernel, name, mac_grant_ok, \ 119 "INT", arg0, arg1); 120 121#define MAC_GRANT_PROBE2(name, error, arg0, arg1) do { \ 122 if (error) { \ 123 SDT_PROBE(mac_framework, kernel, name, mac_grant_err, \ 124 error, arg0, arg1, 0, 0); \ 125 } else { \ 126 SDT_PROBE(mac_framework, kernel, name, mac_grant_ok, \ 127 error, arg0, arg1, 0, 0); \ 128 } \ 129} while (0) 130 131/* 132 * MAC Framework global types and typedefs. 133 */ 134LIST_HEAD(mac_policy_list_head, mac_policy_conf); 135#ifdef MALLOC_DECLARE 136MALLOC_DECLARE(M_MACTEMP); 137#endif 138 139/* 140 * MAC labels -- in-kernel storage format. 141 * 142 * In general, struct label pointers are embedded in kernel data structures 143 * representing objects that may be labeled (and protected). Struct label is 144 * opaque to both kernel services that invoke the MAC Framework and MAC 145 * policy modules. In particular, we do not wish to encode the layout of the 146 * label structure into any ABIs. Historically, the slot array contained 147 * unions of {long, void} but now contains uintptr_t. 148 */ 149#define MAC_MAX_SLOTS 4 150#define MAC_FLAG_INITIALIZED 0x0000001 /* Is initialized for use. */ 151struct label { 152 int l_flags; 153 intptr_t l_perpolicy[MAC_MAX_SLOTS]; 154}; 155 156 157/* 158 * Flags for mac_labeled, a bitmask of object types need across the union of 159 * all policies currently registered with the MAC Framework, used to key 160 * whether or not labels are allocated and constructors for the type are 161 * invoked. 162 */ 163#define MPC_OBJECT_CRED 0x0000000000000001 164#define MPC_OBJECT_PROC 0x0000000000000002 165#define MPC_OBJECT_VNODE 0x0000000000000004 166#define MPC_OBJECT_INPCB 0x0000000000000008 167#define MPC_OBJECT_SOCKET 0x0000000000000010 168#define MPC_OBJECT_DEVFS 0x0000000000000020 169#define MPC_OBJECT_MBUF 0x0000000000000040 170#define MPC_OBJECT_IPQ 0x0000000000000080 171#define MPC_OBJECT_IFNET 0x0000000000000100 172#define MPC_OBJECT_BPFDESC 0x0000000000000200 173#define MPC_OBJECT_PIPE 0x0000000000000400 174#define MPC_OBJECT_MOUNT 0x0000000000000800 175#define MPC_OBJECT_POSIXSEM 0x0000000000001000 176#define MPC_OBJECT_POSIXSHM 0x0000000000002000 177#define MPC_OBJECT_SYSVMSG 0x0000000000004000 178#define MPC_OBJECT_SYSVMSQ 0x0000000000008000 179#define MPC_OBJECT_SYSVSEM 0x0000000000010000 180#define MPC_OBJECT_SYSVSHM 0x0000000000020000 181#define MPC_OBJECT_SYNCACHE 0x0000000000040000 182#define MPC_OBJECT_IP6Q 0x0000000000080000 183 184/* 185 * MAC Framework global variables. 186 */ 187extern struct mac_policy_list_head mac_policy_list; 188extern struct mac_policy_list_head mac_static_policy_list; 189extern uint64_t mac_labeled; 190extern struct mtx mac_ifnet_mtx; 191 192/* 193 * MAC Framework infrastructure functions. 194 */ 195int mac_error_select(int error1, int error2); 196 197void mac_policy_slock_nosleep(void); 198void mac_policy_slock_sleep(void); 199void mac_policy_sunlock_nosleep(void); 200void mac_policy_sunlock_sleep(void); 201 202struct label *mac_labelzone_alloc(int flags); 203void mac_labelzone_free(struct label *label); 204void mac_labelzone_init(void); 205 206void mac_init_label(struct label *label); 207void mac_destroy_label(struct label *label); 208int mac_check_structmac_consistent(struct mac *mac); 209int mac_allocate_slot(void); 210 211#define MAC_IFNET_LOCK(ifp) mtx_lock(&mac_ifnet_mtx) 212#define MAC_IFNET_UNLOCK(ifp) mtx_unlock(&mac_ifnet_mtx) 213 214/* 215 * MAC Framework per-object type functions. It's not yet clear how the 216 * namespaces, etc, should work for these, so for now, sort by object type. 217 */ 218struct label *mac_cred_label_alloc(void); 219void mac_cred_label_free(struct label *label); 220struct label *mac_pipe_label_alloc(void); 221void mac_pipe_label_free(struct label *label); 222struct label *mac_socket_label_alloc(int flag); 223void mac_socket_label_free(struct label *label); 224struct label *mac_vnode_label_alloc(void); 225void mac_vnode_label_free(struct label *label); 226 227int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 228int mac_cred_externalize_label(struct label *label, char *elements, 229 char *outbuf, size_t outbuflen); 230int mac_cred_internalize_label(struct label *label, char *string); 231void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 232 233struct label *mac_mbuf_to_label(struct mbuf *m); 234 235void mac_pipe_copy_label(struct label *src, struct label *dest); 236int mac_pipe_externalize_label(struct label *label, char *elements, 237 char *outbuf, size_t outbuflen); 238int mac_pipe_internalize_label(struct label *label, char *string); 239 240int mac_socket_label_set(struct ucred *cred, struct socket *so, 241 struct label *label); 242void mac_socket_copy_label(struct label *src, struct label *dest); 243int mac_socket_externalize_label(struct label *label, char *elements, 244 char *outbuf, size_t outbuflen); 245int mac_socket_internalize_label(struct label *label, char *string); 246 247int mac_vnode_externalize_label(struct label *label, char *elements, 248 char *outbuf, size_t outbuflen); 249int mac_vnode_internalize_label(struct label *label, char *string); 250void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 251 int *prot); 252int vn_setlabel(struct vnode *vp, struct label *intlabel, 253 struct ucred *cred); 254 255/* 256 * MAC Framework composition macros invoke all registered MAC policies for a 257 * specific entry point. They come in two forms: one which permits policies 258 * to sleep/block, and another that does not. 259 * 260 * MAC_POLICY_CHECK performs the designated check by walking the policy 261 * module list and checking with each as to how it feels about the request. 262 * Note that it returns its value via 'error' in the scope of the caller. 263 */ 264#define MAC_POLICY_CHECK(check, args...) do { \ 265 struct mac_policy_conf *mpc; \ 266 \ 267 error = 0; \ 268 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 269 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 270 error = mac_error_select( \ 271 mpc->mpc_ops->mpo_ ## check (args), \ 272 error); \ 273 } \ 274 if (!LIST_EMPTY(&mac_policy_list)) { \ 275 mac_policy_slock_sleep(); \ 276 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 277 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 278 error = mac_error_select( \ 279 mpc->mpc_ops->mpo_ ## check (args), \ 280 error); \ 281 } \ 282 mac_policy_sunlock_sleep(); \ 283 } \ 284} while (0) 285 286#define MAC_POLICY_CHECK_NOSLEEP(check, args...) do { \ 287 struct mac_policy_conf *mpc; \ 288 \ 289 error = 0; \ 290 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 291 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 292 error = mac_error_select( \ 293 mpc->mpc_ops->mpo_ ## check (args), \ 294 error); \ 295 } \ 296 if (!LIST_EMPTY(&mac_policy_list)) { \ 297 mac_policy_slock_nosleep(); \ 298 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 299 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 300 error = mac_error_select( \ 301 mpc->mpc_ops->mpo_ ## check (args), \ 302 error); \ 303 } \ 304 mac_policy_sunlock_nosleep(); \ 305 } \ 306} while (0) 307 308/* 309 * MAC_POLICY_GRANT performs the designated check by walking the policy 310 * module list and checking with each as to how it feels about the request. 311 * Unlike MAC_POLICY_CHECK, it grants if any policies return '0', and 312 * otherwise returns EPERM. Note that it returns its value via 'error' in 313 * the scope of the caller. 314 */ 315#define MAC_POLICY_GRANT_NOSLEEP(check, args...) do { \ 316 struct mac_policy_conf *mpc; \ 317 \ 318 error = EPERM; \ 319 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 320 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 321 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 322 error = 0; \ 323 } \ 324 } \ 325 if (!LIST_EMPTY(&mac_policy_list)) { \ 326 mac_policy_slock_nosleep(); \ 327 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 328 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 329 if (mpc->mpc_ops->mpo_ ## check (args) \ 330 == 0) \ 331 error = 0; \ 332 } \ 333 } \ 334 mac_policy_sunlock_nosleep(); \ 335 } \ 336} while (0) 337 338/* 339 * MAC_POLICY_BOOLEAN performs the designated boolean composition by walking 340 * the module list, invoking each instance of the operation, and combining 341 * the results using the passed C operator. Note that it returns its value 342 * via 'result' in the scope of the caller, which should be initialized by 343 * the caller in a meaningful way to get a meaningful result. 344 */ 345#define MAC_POLICY_BOOLEAN(operation, composition, args...) do { \ 346 struct mac_policy_conf *mpc; \ 347 \ 348 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 349 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 350 result = result composition \ 351 mpc->mpc_ops->mpo_ ## operation (args); \ 352 } \ 353 if (!LIST_EMPTY(&mac_policy_list)) { \ 354 mac_policy_slock_sleep(); \ 355 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 356 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 357 result = result composition \ 358 mpc->mpc_ops->mpo_ ## operation \ 359 (args); \ 360 } \ 361 mac_policy_sunlock_sleep(); \ 362 } \ 363} while (0) 364 365#define MAC_POLICY_BOOLEAN_NOSLEEP(operation, composition, args...) do {\ 366 struct mac_policy_conf *mpc; \ 367 \ 368 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 369 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 370 result = result composition \ 371 mpc->mpc_ops->mpo_ ## operation (args); \ 372 } \ 373 if (!LIST_EMPTY(&mac_policy_list)) { \ 374 mac_policy_slock_nosleep(); \ 375 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 376 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 377 result = result composition \ 378 mpc->mpc_ops->mpo_ ## operation \ 379 (args); \ 380 } \ 381 mac_policy_sunlock_nosleep(); \ 382 } \ 383} while (0) 384 385/* 386 * MAC_POLICY_EXTERNALIZE queries each policy to see if it can generate an 387 * externalized version of a label element by name. Policies declare whether 388 * they have matched a particular element name, parsed from the string by 389 * MAC_POLICY_EXTERNALIZE, and an error is returned if any element is matched 390 * by no policy. 391 */ 392#define MAC_POLICY_EXTERNALIZE(type, label, elementlist, outbuf, \ 393 outbuflen) do { \ 394 int claimed, first, ignorenotfound, savedlen; \ 395 char *element_name, *element_temp; \ 396 struct sbuf sb; \ 397 \ 398 error = 0; \ 399 first = 1; \ 400 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 401 element_temp = elementlist; \ 402 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 403 if (element_name[0] == '?') { \ 404 element_name++; \ 405 ignorenotfound = 1; \ 406 } else \ 407 ignorenotfound = 0; \ 408 savedlen = sbuf_len(&sb); \ 409 if (first) \ 410 error = sbuf_printf(&sb, "%s/", element_name); \ 411 else \ 412 error = sbuf_printf(&sb, ",%s/", element_name); \ 413 if (error == -1) { \ 414 error = EINVAL; /* XXX: E2BIG? */ \ 415 break; \ 416 } \ 417 claimed = 0; \ 418 MAC_POLICY_CHECK(type ## _externalize_label, label, \ 419 element_name, &sb, &claimed); \ 420 if (error) \ 421 break; \ 422 if (claimed == 0 && ignorenotfound) { \ 423 /* Revert last label name. */ \ 424 sbuf_setpos(&sb, savedlen); \ 425 } else if (claimed != 1) { \ 426 error = EINVAL; /* XXX: ENOLABEL? */ \ 427 break; \ 428 } else { \ 429 first = 0; \ 430 } \ 431 } \ 432 sbuf_finish(&sb); \ 433} while (0) 434 435/* 436 * MAC_POLICY_INTERNALIZE presents parsed element names and data to each 437 * policy to see if any is willing to claim it and internalize the label 438 * data. If no policies match, an error is returned. 439 */ 440#define MAC_POLICY_INTERNALIZE(type, label, instring) do { \ 441 char *element, *element_name, *element_data; \ 442 int claimed; \ 443 \ 444 error = 0; \ 445 element = instring; \ 446 while ((element_name = strsep(&element, ",")) != NULL) { \ 447 element_data = element_name; \ 448 element_name = strsep(&element_data, "/"); \ 449 if (element_data == NULL) { \ 450 error = EINVAL; \ 451 break; \ 452 } \ 453 claimed = 0; \ 454 MAC_POLICY_CHECK(type ## _internalize_label, label, \ 455 element_name, element_data, &claimed); \ 456 if (error) \ 457 break; \ 458 if (claimed != 1) { \ 459 /* XXXMAC: Another error here? */ \ 460 error = EINVAL; \ 461 break; \ 462 } \ 463 } \ 464} while (0) 465 466/* 467 * MAC_POLICY_PERFORM performs the designated operation by walking the policy 468 * module list and invoking that operation for each policy. 469 */ 470#define MAC_POLICY_PERFORM(operation, args...) do { \ 471 struct mac_policy_conf *mpc; \ 472 \ 473 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 474 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 475 mpc->mpc_ops->mpo_ ## operation (args); \ 476 } \ 477 if (!LIST_EMPTY(&mac_policy_list)) { \ 478 mac_policy_slock_sleep(); \ 479 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 480 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 481 mpc->mpc_ops->mpo_ ## operation (args); \ 482 } \ 483 mac_policy_sunlock_sleep(); \ 484 } \ 485} while (0) 486 487#define MAC_POLICY_PERFORM_NOSLEEP(operation, args...) do { \ 488 struct mac_policy_conf *mpc; \ 489 \ 490 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 491 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 492 mpc->mpc_ops->mpo_ ## operation (args); \ 493 } \ 494 if (!LIST_EMPTY(&mac_policy_list)) { \ 495 mac_policy_slock_nosleep(); \ 496 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 497 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 498 mpc->mpc_ops->mpo_ ## operation (args); \ 499 } \ 500 mac_policy_sunlock_nosleep(); \ 501 } \ 502} while (0) 503 504#endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 505