1 /*- 2 * Copyright (c) 1999-2002, 2006, 2009, 2019 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 * $FreeBSD$ 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 65 SYSCTL_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 73 SDT_PROVIDER_DECLARE(mac); /* MAC Framework-level events. */ 74 SDT_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, , name, mac__check__err, \ 78 "int", arg0, arg1, arg2, arg3); \ 79 SDT_PROBE_DEFINE5(mac_framework, , 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, , name, mac__check__err, \ 84 "int", arg0, arg1, arg2); \ 85 SDT_PROBE_DEFINE4(mac_framework, , 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, , name, mac__check__err, \ 90 "int", arg0, arg1); \ 91 SDT_PROBE_DEFINE3(mac_framework, , name, mac__check__ok, \ 92 "int", arg0, arg1); 93 94 #define MAC_CHECK_PROBE_DEFINE1(name, arg0) \ 95 SDT_PROBE_DEFINE2(mac_framework, , name, mac__check__err, \ 96 "int", arg0); \ 97 SDT_PROBE_DEFINE2(mac_framework, , name, mac__check__ok, \ 98 "int", arg0); 99 100 #define MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, arg3) do { \ 101 if (SDT_PROBES_ENABLED()) { \ 102 if (error) { \ 103 SDT_PROBE5(mac_framework, , name, mac__check__err,\ 104 error, arg0, arg1, arg2, arg3); \ 105 } else { \ 106 SDT_PROBE5(mac_framework, , name, mac__check__ok,\ 107 0, arg0, arg1, arg2, arg3); \ 108 } \ 109 } \ 110 } while (0) 111 112 #define MAC_CHECK_PROBE3(name, error, arg0, arg1, arg2) \ 113 MAC_CHECK_PROBE4(name, error, arg0, arg1, arg2, 0) 114 #define MAC_CHECK_PROBE2(name, error, arg0, arg1) \ 115 MAC_CHECK_PROBE3(name, error, arg0, arg1, 0) 116 #define MAC_CHECK_PROBE1(name, error, arg0) \ 117 MAC_CHECK_PROBE2(name, error, arg0, 0) 118 #endif 119 120 #define MAC_GRANT_PROBE_DEFINE2(name, arg0, arg1) \ 121 SDT_PROBE_DEFINE3(mac_framework, , name, mac__grant__err, \ 122 "int", arg0, arg1); \ 123 SDT_PROBE_DEFINE3(mac_framework, , name, mac__grant__ok, \ 124 "int", arg0, arg1); 125 126 #define MAC_GRANT_PROBE2(name, error, arg0, arg1) do { \ 127 if (SDT_PROBES_ENABLED()) { \ 128 if (error) { \ 129 SDT_PROBE3(mac_framework, , name, mac__grant__err,\ 130 error, arg0, arg1); \ 131 } else { \ 132 SDT_PROBE3(mac_framework, , name, mac__grant__ok,\ 133 error, arg0, arg1); \ 134 } \ 135 } \ 136 } while (0) 137 138 /* 139 * MAC Framework global types and typedefs. 140 */ 141 LIST_HEAD(mac_policy_list_head, mac_policy_conf); 142 #ifdef MALLOC_DECLARE 143 MALLOC_DECLARE(M_MACTEMP); 144 #endif 145 146 /* 147 * MAC labels -- in-kernel storage format. 148 * 149 * In general, struct label pointers are embedded in kernel data structures 150 * representing objects that may be labeled (and protected). Struct label is 151 * opaque to both kernel services that invoke the MAC Framework and MAC 152 * policy modules. In particular, we do not wish to encode the layout of the 153 * label structure into any ABIs. Historically, the slot array contained 154 * unions of {long, void} but now contains uintptr_t. 155 */ 156 #define MAC_MAX_SLOTS 4 157 #define MAC_FLAG_INITIALIZED 0x0000001 /* Is initialized for use. */ 158 struct label { 159 int l_flags; 160 intptr_t l_perpolicy[MAC_MAX_SLOTS]; 161 }; 162 163 /* 164 * Flags for mac_labeled, a bitmask of object types need across the union of 165 * all policies currently registered with the MAC Framework, used to key 166 * whether or not labels are allocated and constructors for the type are 167 * invoked. 168 */ 169 #define MPC_OBJECT_CRED 0x0000000000000001 170 #define MPC_OBJECT_PROC 0x0000000000000002 171 #define MPC_OBJECT_VNODE 0x0000000000000004 172 #define MPC_OBJECT_INPCB 0x0000000000000008 173 #define MPC_OBJECT_SOCKET 0x0000000000000010 174 #define MPC_OBJECT_DEVFS 0x0000000000000020 175 #define MPC_OBJECT_MBUF 0x0000000000000040 176 #define MPC_OBJECT_IPQ 0x0000000000000080 177 #define MPC_OBJECT_IFNET 0x0000000000000100 178 #define MPC_OBJECT_BPFDESC 0x0000000000000200 179 #define MPC_OBJECT_PIPE 0x0000000000000400 180 #define MPC_OBJECT_MOUNT 0x0000000000000800 181 #define MPC_OBJECT_POSIXSEM 0x0000000000001000 182 #define MPC_OBJECT_POSIXSHM 0x0000000000002000 183 #define MPC_OBJECT_SYSVMSG 0x0000000000004000 184 #define MPC_OBJECT_SYSVMSQ 0x0000000000008000 185 #define MPC_OBJECT_SYSVSEM 0x0000000000010000 186 #define MPC_OBJECT_SYSVSHM 0x0000000000020000 187 #define MPC_OBJECT_SYNCACHE 0x0000000000040000 188 #define MPC_OBJECT_IP6Q 0x0000000000080000 189 190 /* 191 * MAC Framework global variables. 192 */ 193 extern struct mac_policy_list_head mac_policy_list; 194 extern struct mac_policy_list_head mac_static_policy_list; 195 extern u_int mac_policy_count; 196 extern uint64_t mac_labeled; 197 extern struct mtx mac_ifnet_mtx; 198 199 /* 200 * MAC Framework infrastructure functions. 201 */ 202 int mac_error_select(int error1, int error2); 203 204 void mac_policy_slock_nosleep(struct rm_priotracker *tracker); 205 void mac_policy_slock_sleep(void); 206 void mac_policy_sunlock_nosleep(struct rm_priotracker *tracker); 207 void mac_policy_sunlock_sleep(void); 208 209 struct label *mac_labelzone_alloc(int flags); 210 void mac_labelzone_free(struct label *label); 211 void mac_labelzone_init(void); 212 213 void mac_init_label(struct label *label); 214 void mac_destroy_label(struct label *label); 215 int mac_check_structmac_consistent(struct mac *mac); 216 int mac_allocate_slot(void); 217 218 /* 219 * Lock ifnets to protect labels only if ifnet labels are in use. 220 */ 221 #define MAC_IFNET_LOCK(ifp, locked) do { \ 222 if (mac_labeled & MPC_OBJECT_IFNET) { \ 223 mtx_lock(&mac_ifnet_mtx); \ 224 locked = 1; \ 225 } else { \ 226 locked = 0; \ 227 } \ 228 } while (0) 229 230 #define MAC_IFNET_UNLOCK(ifp, locked) do { \ 231 if (locked) { \ 232 mtx_unlock(&mac_ifnet_mtx); \ 233 locked = 0; \ 234 } \ 235 } while (0) 236 237 /* 238 * MAC Framework per-object type functions. It's not yet clear how the 239 * namespaces, etc, should work for these, so for now, sort by object type. 240 */ 241 struct label *mac_cred_label_alloc(void); 242 void mac_cred_label_free(struct label *label); 243 struct label *mac_pipe_label_alloc(void); 244 void mac_pipe_label_free(struct label *label); 245 struct label *mac_socket_label_alloc(int flag); 246 void mac_socket_label_free(struct label *label); 247 struct label *mac_vnode_label_alloc(void); 248 void mac_vnode_label_free(struct label *label); 249 250 int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 251 int mac_cred_externalize_label(struct label *label, char *elements, 252 char *outbuf, size_t outbuflen); 253 int mac_cred_internalize_label(struct label *label, char *string); 254 void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 255 256 struct label *mac_mbuf_to_label(struct mbuf *m); 257 258 void mac_pipe_copy_label(struct label *src, struct label *dest); 259 int mac_pipe_externalize_label(struct label *label, char *elements, 260 char *outbuf, size_t outbuflen); 261 int mac_pipe_internalize_label(struct label *label, char *string); 262 263 int mac_socket_label_set(struct ucred *cred, struct socket *so, 264 struct label *label); 265 void mac_socket_copy_label(struct label *src, struct label *dest); 266 int mac_socket_externalize_label(struct label *label, char *elements, 267 char *outbuf, size_t outbuflen); 268 int mac_socket_internalize_label(struct label *label, char *string); 269 270 int mac_vnode_externalize_label(struct label *label, char *elements, 271 char *outbuf, size_t outbuflen); 272 int mac_vnode_internalize_label(struct label *label, char *string); 273 void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 274 int *prot); 275 int vn_setlabel(struct vnode *vp, struct label *intlabel, 276 struct ucred *cred); 277 278 /* 279 * MAC Framework composition macros invoke all registered MAC policies for a 280 * specific entry point. They come in two forms: one which permits policies 281 * to sleep/block, and another that does not. 282 * 283 * MAC_POLICY_CHECK performs the designated check by walking the policy 284 * module list and checking with each as to how it feels about the request. 285 * Note that it returns its value via 'error' in the scope of the caller. 286 */ 287 #define MAC_POLICY_CHECK(check, args...) do { \ 288 struct mac_policy_conf *mpc; \ 289 \ 290 error = 0; \ 291 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 292 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 293 error = mac_error_select( \ 294 mpc->mpc_ops->mpo_ ## check (args), \ 295 error); \ 296 } \ 297 if (!LIST_EMPTY(&mac_policy_list)) { \ 298 mac_policy_slock_sleep(); \ 299 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 300 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 301 error = mac_error_select( \ 302 mpc->mpc_ops->mpo_ ## check (args), \ 303 error); \ 304 } \ 305 mac_policy_sunlock_sleep(); \ 306 } \ 307 } while (0) 308 309 #define MAC_POLICY_CHECK_NOSLEEP(check, args...) do { \ 310 struct mac_policy_conf *mpc; \ 311 \ 312 error = 0; \ 313 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 314 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 315 error = mac_error_select( \ 316 mpc->mpc_ops->mpo_ ## check (args), \ 317 error); \ 318 } \ 319 if (!LIST_EMPTY(&mac_policy_list)) { \ 320 struct rm_priotracker tracker; \ 321 \ 322 mac_policy_slock_nosleep(&tracker); \ 323 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 324 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 325 error = mac_error_select( \ 326 mpc->mpc_ops->mpo_ ## check (args), \ 327 error); \ 328 } \ 329 mac_policy_sunlock_nosleep(&tracker); \ 330 } \ 331 } while (0) 332 333 /* 334 * MAC_POLICY_GRANT performs the designated check by walking the policy 335 * module list and checking with each as to how it feels about the request. 336 * Unlike MAC_POLICY_CHECK, it grants if any policies return '0', and 337 * otherwise returns EPERM. Note that it returns its value via 'error' in 338 * the scope of the caller. 339 */ 340 #define MAC_POLICY_GRANT_NOSLEEP(check, args...) do { \ 341 struct mac_policy_conf *mpc; \ 342 \ 343 error = EPERM; \ 344 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 345 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 346 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 347 error = 0; \ 348 } \ 349 } \ 350 if (!LIST_EMPTY(&mac_policy_list)) { \ 351 struct rm_priotracker tracker; \ 352 \ 353 mac_policy_slock_nosleep(&tracker); \ 354 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 355 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 356 if (mpc->mpc_ops->mpo_ ## check (args) \ 357 == 0) \ 358 error = 0; \ 359 } \ 360 } \ 361 mac_policy_sunlock_nosleep(&tracker); \ 362 } \ 363 } while (0) 364 365 /* 366 * MAC_POLICY_BOOLEAN performs the designated boolean composition by walking 367 * the module list, invoking each instance of the operation, and combining 368 * the results using the passed C operator. Note that it returns its value 369 * via 'result' in the scope of the caller, which should be initialized by 370 * the caller in a meaningful way to get a meaningful result. 371 */ 372 #define MAC_POLICY_BOOLEAN(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 mac_policy_slock_sleep(); \ 382 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 383 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 384 result = result composition \ 385 mpc->mpc_ops->mpo_ ## operation \ 386 (args); \ 387 } \ 388 mac_policy_sunlock_sleep(); \ 389 } \ 390 } while (0) 391 392 #define MAC_POLICY_BOOLEAN_NOSLEEP(operation, composition, args...) do {\ 393 struct mac_policy_conf *mpc; \ 394 \ 395 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 396 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 397 result = result composition \ 398 mpc->mpc_ops->mpo_ ## operation (args); \ 399 } \ 400 if (!LIST_EMPTY(&mac_policy_list)) { \ 401 struct rm_priotracker tracker; \ 402 \ 403 mac_policy_slock_nosleep(&tracker); \ 404 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 405 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 406 result = result composition \ 407 mpc->mpc_ops->mpo_ ## operation \ 408 (args); \ 409 } \ 410 mac_policy_sunlock_nosleep(&tracker); \ 411 } \ 412 } while (0) 413 414 /* 415 * MAC_POLICY_EXTERNALIZE queries each policy to see if it can generate an 416 * externalized version of a label element by name. Policies declare whether 417 * they have matched a particular element name, parsed from the string by 418 * MAC_POLICY_EXTERNALIZE, and an error is returned if any element is matched 419 * by no policy. 420 */ 421 #define MAC_POLICY_EXTERNALIZE(type, label, elementlist, outbuf, \ 422 outbuflen) do { \ 423 int claimed, first, ignorenotfound, savedlen; \ 424 char *element_name, *element_temp; \ 425 struct sbuf sb; \ 426 \ 427 error = 0; \ 428 first = 1; \ 429 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 430 element_temp = elementlist; \ 431 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 432 if (element_name[0] == '?') { \ 433 element_name++; \ 434 ignorenotfound = 1; \ 435 } else \ 436 ignorenotfound = 0; \ 437 savedlen = sbuf_len(&sb); \ 438 if (first) \ 439 error = sbuf_printf(&sb, "%s/", element_name); \ 440 else \ 441 error = sbuf_printf(&sb, ",%s/", element_name); \ 442 if (error == -1) { \ 443 error = EINVAL; /* XXX: E2BIG? */ \ 444 break; \ 445 } \ 446 claimed = 0; \ 447 MAC_POLICY_CHECK(type ## _externalize_label, label, \ 448 element_name, &sb, &claimed); \ 449 if (error) \ 450 break; \ 451 if (claimed == 0 && ignorenotfound) { \ 452 /* Revert last label name. */ \ 453 sbuf_setpos(&sb, savedlen); \ 454 } else if (claimed != 1) { \ 455 error = EINVAL; /* XXX: ENOLABEL? */ \ 456 break; \ 457 } else { \ 458 first = 0; \ 459 } \ 460 } \ 461 sbuf_finish(&sb); \ 462 } while (0) 463 464 /* 465 * MAC_POLICY_INTERNALIZE presents parsed element names and data to each 466 * policy to see if any is willing to claim it and internalize the label 467 * data. If no policies match, an error is returned. 468 */ 469 #define MAC_POLICY_INTERNALIZE(type, label, instring) do { \ 470 char *element, *element_name, *element_data; \ 471 int claimed; \ 472 \ 473 error = 0; \ 474 element = instring; \ 475 while ((element_name = strsep(&element, ",")) != NULL) { \ 476 element_data = element_name; \ 477 element_name = strsep(&element_data, "/"); \ 478 if (element_data == NULL) { \ 479 error = EINVAL; \ 480 break; \ 481 } \ 482 claimed = 0; \ 483 MAC_POLICY_CHECK(type ## _internalize_label, label, \ 484 element_name, element_data, &claimed); \ 485 if (error) \ 486 break; \ 487 if (claimed != 1) { \ 488 /* XXXMAC: Another error here? */ \ 489 error = EINVAL; \ 490 break; \ 491 } \ 492 } \ 493 } while (0) 494 495 /* 496 * MAC_POLICY_PERFORM performs the designated operation by walking the policy 497 * module list and invoking that operation for each policy. 498 */ 499 #define MAC_POLICY_PERFORM(operation, args...) do { \ 500 struct mac_policy_conf *mpc; \ 501 \ 502 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 503 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 504 mpc->mpc_ops->mpo_ ## operation (args); \ 505 } \ 506 if (!LIST_EMPTY(&mac_policy_list)) { \ 507 mac_policy_slock_sleep(); \ 508 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 509 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 510 mpc->mpc_ops->mpo_ ## operation (args); \ 511 } \ 512 mac_policy_sunlock_sleep(); \ 513 } \ 514 } while (0) 515 516 #define MAC_POLICY_PERFORM_NOSLEEP(operation, args...) do { \ 517 struct mac_policy_conf *mpc; \ 518 \ 519 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 520 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 521 mpc->mpc_ops->mpo_ ## operation (args); \ 522 } \ 523 if (!LIST_EMPTY(&mac_policy_list)) { \ 524 struct rm_priotracker tracker; \ 525 \ 526 mac_policy_slock_nosleep(&tracker); \ 527 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 528 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 529 mpc->mpc_ops->mpo_ ## operation (args); \ 530 } \ 531 mac_policy_sunlock_nosleep(&tracker); \ 532 } \ 533 } while (0) 534 535 #endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 536