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 /* 165 * Flags for mac_labeled, a bitmask of object types need across the union of 166 * all policies currently registered with the MAC Framework, used to key 167 * whether or not labels are allocated and constructors for the type are 168 * invoked. 169 */ 170 #define MPC_OBJECT_CRED 0x0000000000000001 171 #define MPC_OBJECT_PROC 0x0000000000000002 172 #define MPC_OBJECT_VNODE 0x0000000000000004 173 #define MPC_OBJECT_INPCB 0x0000000000000008 174 #define MPC_OBJECT_SOCKET 0x0000000000000010 175 #define MPC_OBJECT_DEVFS 0x0000000000000020 176 #define MPC_OBJECT_MBUF 0x0000000000000040 177 #define MPC_OBJECT_IPQ 0x0000000000000080 178 #define MPC_OBJECT_IFNET 0x0000000000000100 179 #define MPC_OBJECT_BPFDESC 0x0000000000000200 180 #define MPC_OBJECT_PIPE 0x0000000000000400 181 #define MPC_OBJECT_MOUNT 0x0000000000000800 182 #define MPC_OBJECT_POSIXSEM 0x0000000000001000 183 #define MPC_OBJECT_POSIXSHM 0x0000000000002000 184 #define MPC_OBJECT_SYSVMSG 0x0000000000004000 185 #define MPC_OBJECT_SYSVMSQ 0x0000000000008000 186 #define MPC_OBJECT_SYSVSEM 0x0000000000010000 187 #define MPC_OBJECT_SYSVSHM 0x0000000000020000 188 #define MPC_OBJECT_SYNCACHE 0x0000000000040000 189 #define MPC_OBJECT_IP6Q 0x0000000000080000 190 191 /* 192 * MAC Framework global variables. 193 */ 194 extern struct mac_policy_list_head mac_policy_list; 195 extern struct mac_policy_list_head mac_static_policy_list; 196 extern u_int mac_policy_count; 197 extern uint64_t mac_labeled; 198 extern struct mtx mac_ifnet_mtx; 199 200 /* 201 * MAC Framework infrastructure functions. 202 */ 203 int mac_error_select(int error1, int error2); 204 205 void mac_policy_slock_nosleep(struct rm_priotracker *tracker); 206 void mac_policy_slock_sleep(void); 207 void mac_policy_sunlock_nosleep(struct rm_priotracker *tracker); 208 void mac_policy_sunlock_sleep(void); 209 210 struct label *mac_labelzone_alloc(int flags); 211 void mac_labelzone_free(struct label *label); 212 void mac_labelzone_init(void); 213 214 void mac_init_label(struct label *label); 215 void mac_destroy_label(struct label *label); 216 int mac_check_structmac_consistent(struct mac *mac); 217 int mac_allocate_slot(void); 218 219 /* 220 * Lock ifnets to protect labels only if ifnet labels are in use. 221 */ 222 #define MAC_IFNET_LOCK(ifp, locked) do { \ 223 if (mac_labeled & MPC_OBJECT_IFNET) { \ 224 mtx_lock(&mac_ifnet_mtx); \ 225 locked = 1; \ 226 } else { \ 227 locked = 0; \ 228 } \ 229 } while (0) 230 231 #define MAC_IFNET_UNLOCK(ifp, locked) do { \ 232 if (locked) { \ 233 mtx_unlock(&mac_ifnet_mtx); \ 234 locked = 0; \ 235 } \ 236 } while (0) 237 238 /* 239 * MAC Framework per-object type functions. It's not yet clear how the 240 * namespaces, etc, should work for these, so for now, sort by object type. 241 */ 242 struct label *mac_cred_label_alloc(void); 243 void mac_cred_label_free(struct label *label); 244 struct label *mac_pipe_label_alloc(void); 245 void mac_pipe_label_free(struct label *label); 246 struct label *mac_socket_label_alloc(int flag); 247 void mac_socket_label_free(struct label *label); 248 struct label *mac_vnode_label_alloc(void); 249 void mac_vnode_label_free(struct label *label); 250 251 int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 252 int mac_cred_externalize_label(struct label *label, char *elements, 253 char *outbuf, size_t outbuflen); 254 int mac_cred_internalize_label(struct label *label, char *string); 255 void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 256 257 struct label *mac_mbuf_to_label(struct mbuf *m); 258 259 void mac_pipe_copy_label(struct label *src, struct label *dest); 260 int mac_pipe_externalize_label(struct label *label, char *elements, 261 char *outbuf, size_t outbuflen); 262 int mac_pipe_internalize_label(struct label *label, char *string); 263 264 int mac_socket_label_set(struct ucred *cred, struct socket *so, 265 struct label *label); 266 void mac_socket_copy_label(struct label *src, struct label *dest); 267 int mac_socket_externalize_label(struct label *label, char *elements, 268 char *outbuf, size_t outbuflen); 269 int mac_socket_internalize_label(struct label *label, char *string); 270 271 int mac_vnode_externalize_label(struct label *label, char *elements, 272 char *outbuf, size_t outbuflen); 273 int mac_vnode_internalize_label(struct label *label, char *string); 274 void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 275 int *prot); 276 int vn_setlabel(struct vnode *vp, struct label *intlabel, 277 struct ucred *cred); 278 279 /* 280 * MAC Framework composition macros invoke all registered MAC policies for a 281 * specific entry point. They come in two forms: one which permits policies 282 * to sleep/block, and another that does not. 283 * 284 * MAC_POLICY_CHECK performs the designated check by walking the policy 285 * module list and checking with each as to how it feels about the request. 286 * Note that it returns its value via 'error' in the scope of the caller. 287 */ 288 #define MAC_POLICY_CHECK(check, args...) do { \ 289 struct mac_policy_conf *mpc; \ 290 \ 291 error = 0; \ 292 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 293 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 294 error = mac_error_select( \ 295 mpc->mpc_ops->mpo_ ## check (args), \ 296 error); \ 297 } \ 298 if (!LIST_EMPTY(&mac_policy_list)) { \ 299 mac_policy_slock_sleep(); \ 300 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 301 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 302 error = mac_error_select( \ 303 mpc->mpc_ops->mpo_ ## check (args), \ 304 error); \ 305 } \ 306 mac_policy_sunlock_sleep(); \ 307 } \ 308 } while (0) 309 310 #define MAC_POLICY_CHECK_NOSLEEP(check, args...) do { \ 311 struct mac_policy_conf *mpc; \ 312 \ 313 error = 0; \ 314 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 315 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 316 error = mac_error_select( \ 317 mpc->mpc_ops->mpo_ ## check (args), \ 318 error); \ 319 } \ 320 if (!LIST_EMPTY(&mac_policy_list)) { \ 321 struct rm_priotracker tracker; \ 322 \ 323 mac_policy_slock_nosleep(&tracker); \ 324 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 325 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 326 error = mac_error_select( \ 327 mpc->mpc_ops->mpo_ ## check (args), \ 328 error); \ 329 } \ 330 mac_policy_sunlock_nosleep(&tracker); \ 331 } \ 332 } while (0) 333 334 /* 335 * MAC_POLICY_GRANT performs the designated check by walking the policy 336 * module list and checking with each as to how it feels about the request. 337 * Unlike MAC_POLICY_CHECK, it grants if any policies return '0', and 338 * otherwise returns EPERM. Note that it returns its value via 'error' in 339 * the scope of the caller. 340 */ 341 #define MAC_POLICY_GRANT_NOSLEEP(check, args...) do { \ 342 struct mac_policy_conf *mpc; \ 343 \ 344 error = EPERM; \ 345 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 346 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 347 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 348 error = 0; \ 349 } \ 350 } \ 351 if (!LIST_EMPTY(&mac_policy_list)) { \ 352 struct rm_priotracker tracker; \ 353 \ 354 mac_policy_slock_nosleep(&tracker); \ 355 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 356 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 357 if (mpc->mpc_ops->mpo_ ## check (args) \ 358 == 0) \ 359 error = 0; \ 360 } \ 361 } \ 362 mac_policy_sunlock_nosleep(&tracker); \ 363 } \ 364 } while (0) 365 366 /* 367 * MAC_POLICY_BOOLEAN performs the designated boolean composition by walking 368 * the module list, invoking each instance of the operation, and combining 369 * the results using the passed C operator. Note that it returns its value 370 * via 'result' in the scope of the caller, which should be initialized by 371 * the caller in a meaningful way to get a meaningful result. 372 */ 373 #define MAC_POLICY_BOOLEAN(operation, composition, args...) do { \ 374 struct mac_policy_conf *mpc; \ 375 \ 376 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 377 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 378 result = result composition \ 379 mpc->mpc_ops->mpo_ ## operation (args); \ 380 } \ 381 if (!LIST_EMPTY(&mac_policy_list)) { \ 382 mac_policy_slock_sleep(); \ 383 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 384 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 385 result = result composition \ 386 mpc->mpc_ops->mpo_ ## operation \ 387 (args); \ 388 } \ 389 mac_policy_sunlock_sleep(); \ 390 } \ 391 } while (0) 392 393 #define MAC_POLICY_BOOLEAN_NOSLEEP(operation, composition, args...) do {\ 394 struct mac_policy_conf *mpc; \ 395 \ 396 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 397 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 398 result = result composition \ 399 mpc->mpc_ops->mpo_ ## operation (args); \ 400 } \ 401 if (!LIST_EMPTY(&mac_policy_list)) { \ 402 struct rm_priotracker tracker; \ 403 \ 404 mac_policy_slock_nosleep(&tracker); \ 405 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 406 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 407 result = result composition \ 408 mpc->mpc_ops->mpo_ ## operation \ 409 (args); \ 410 } \ 411 mac_policy_sunlock_nosleep(&tracker); \ 412 } \ 413 } while (0) 414 415 /* 416 * MAC_POLICY_EXTERNALIZE queries each policy to see if it can generate an 417 * externalized version of a label element by name. Policies declare whether 418 * they have matched a particular element name, parsed from the string by 419 * MAC_POLICY_EXTERNALIZE, and an error is returned if any element is matched 420 * by no policy. 421 */ 422 #define MAC_POLICY_EXTERNALIZE(type, label, elementlist, outbuf, \ 423 outbuflen) do { \ 424 int claimed, first, ignorenotfound, savedlen; \ 425 char *element_name, *element_temp; \ 426 struct sbuf sb; \ 427 \ 428 error = 0; \ 429 first = 1; \ 430 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 431 element_temp = elementlist; \ 432 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 433 if (element_name[0] == '?') { \ 434 element_name++; \ 435 ignorenotfound = 1; \ 436 } else \ 437 ignorenotfound = 0; \ 438 savedlen = sbuf_len(&sb); \ 439 if (first) \ 440 error = sbuf_printf(&sb, "%s/", element_name); \ 441 else \ 442 error = sbuf_printf(&sb, ",%s/", element_name); \ 443 if (error == -1) { \ 444 error = EINVAL; /* XXX: E2BIG? */ \ 445 break; \ 446 } \ 447 claimed = 0; \ 448 MAC_POLICY_CHECK(type ## _externalize_label, label, \ 449 element_name, &sb, &claimed); \ 450 if (error) \ 451 break; \ 452 if (claimed == 0 && ignorenotfound) { \ 453 /* Revert last label name. */ \ 454 sbuf_setpos(&sb, savedlen); \ 455 } else if (claimed != 1) { \ 456 error = EINVAL; /* XXX: ENOLABEL? */ \ 457 break; \ 458 } else { \ 459 first = 0; \ 460 } \ 461 } \ 462 sbuf_finish(&sb); \ 463 } while (0) 464 465 /* 466 * MAC_POLICY_INTERNALIZE presents parsed element names and data to each 467 * policy to see if any is willing to claim it and internalize the label 468 * data. If no policies match, an error is returned. 469 */ 470 #define MAC_POLICY_INTERNALIZE(type, label, instring) do { \ 471 char *element, *element_name, *element_data; \ 472 int claimed; \ 473 \ 474 error = 0; \ 475 element = instring; \ 476 while ((element_name = strsep(&element, ",")) != NULL) { \ 477 element_data = element_name; \ 478 element_name = strsep(&element_data, "/"); \ 479 if (element_data == NULL) { \ 480 error = EINVAL; \ 481 break; \ 482 } \ 483 claimed = 0; \ 484 MAC_POLICY_CHECK(type ## _internalize_label, label, \ 485 element_name, element_data, &claimed); \ 486 if (error) \ 487 break; \ 488 if (claimed != 1) { \ 489 /* XXXMAC: Another error here? */ \ 490 error = EINVAL; \ 491 break; \ 492 } \ 493 } \ 494 } while (0) 495 496 /* 497 * MAC_POLICY_PERFORM performs the designated operation by walking the policy 498 * module list and invoking that operation for each policy. 499 */ 500 #define MAC_POLICY_PERFORM(operation, args...) do { \ 501 struct mac_policy_conf *mpc; \ 502 \ 503 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 504 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 505 mpc->mpc_ops->mpo_ ## operation (args); \ 506 } \ 507 if (!LIST_EMPTY(&mac_policy_list)) { \ 508 mac_policy_slock_sleep(); \ 509 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 510 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 511 mpc->mpc_ops->mpo_ ## operation (args); \ 512 } \ 513 mac_policy_sunlock_sleep(); \ 514 } \ 515 } while (0) 516 517 #define MAC_POLICY_PERFORM_NOSLEEP(operation, args...) do { \ 518 struct mac_policy_conf *mpc; \ 519 \ 520 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 521 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 522 mpc->mpc_ops->mpo_ ## operation (args); \ 523 } \ 524 if (!LIST_EMPTY(&mac_policy_list)) { \ 525 struct rm_priotracker tracker; \ 526 \ 527 mac_policy_slock_nosleep(&tracker); \ 528 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 529 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 530 mpc->mpc_ops->mpo_ ## operation (args); \ 531 } \ 532 mac_policy_sunlock_nosleep(&tracker); \ 533 } \ 534 } while (0) 535 536 #endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 537