mac_internal.h revision 189503
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 189503 2009-03-08 00:50:37Z 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_grab_exclusive(void); 198void mac_policy_assert_exclusive(void); 199void mac_policy_release_exclusive(void); 200void mac_policy_list_busy(void); 201int mac_policy_list_conditional_busy(void); 202void mac_policy_list_unbusy(void); 203 204struct label *mac_labelzone_alloc(int flags); 205void mac_labelzone_free(struct label *label); 206void mac_labelzone_init(void); 207 208void mac_init_label(struct label *label); 209void mac_destroy_label(struct label *label); 210int mac_check_structmac_consistent(struct mac *mac); 211int mac_allocate_slot(void); 212 213#define MAC_IFNET_LOCK(ifp) mtx_lock(&mac_ifnet_mtx) 214#define MAC_IFNET_UNLOCK(ifp) mtx_unlock(&mac_ifnet_mtx) 215 216/* 217 * MAC Framework per-object type functions. It's not yet clear how the 218 * namespaces, etc, should work for these, so for now, sort by object type. 219 */ 220struct label *mac_cred_label_alloc(void); 221void mac_cred_label_free(struct label *label); 222struct label *mac_pipe_label_alloc(void); 223void mac_pipe_label_free(struct label *label); 224struct label *mac_socket_label_alloc(int flag); 225void mac_socket_label_free(struct label *label); 226struct label *mac_vnode_label_alloc(void); 227void mac_vnode_label_free(struct label *label); 228 229int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 230int mac_cred_externalize_label(struct label *label, char *elements, 231 char *outbuf, size_t outbuflen); 232int mac_cred_internalize_label(struct label *label, char *string); 233void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 234 235struct label *mac_mbuf_to_label(struct mbuf *m); 236 237void mac_pipe_copy_label(struct label *src, struct label *dest); 238int mac_pipe_externalize_label(struct label *label, char *elements, 239 char *outbuf, size_t outbuflen); 240int mac_pipe_internalize_label(struct label *label, char *string); 241 242int mac_socket_label_set(struct ucred *cred, struct socket *so, 243 struct label *label); 244void mac_socket_copy_label(struct label *src, struct label *dest); 245int mac_socket_externalize_label(struct label *label, char *elements, 246 char *outbuf, size_t outbuflen); 247int mac_socket_internalize_label(struct label *label, char *string); 248 249int mac_vnode_externalize_label(struct label *label, char *elements, 250 char *outbuf, size_t outbuflen); 251int mac_vnode_internalize_label(struct label *label, char *string); 252void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 253 int *prot); 254int vn_setlabel(struct vnode *vp, struct label *intlabel, 255 struct ucred *cred); 256 257/* 258 * MAC_CHECK performs the designated check by walking the policy module list 259 * and checking with each as to how it feels about the request. Note that it 260 * returns its value via 'error' in the scope of the caller. 261 */ 262#define MAC_CHECK(check, args...) do { \ 263 struct mac_policy_conf *mpc; \ 264 int entrycount; \ 265 \ 266 error = 0; \ 267 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 268 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 269 error = mac_error_select( \ 270 mpc->mpc_ops->mpo_ ## check (args), \ 271 error); \ 272 } \ 273 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 274 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 275 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 276 error = mac_error_select( \ 277 mpc->mpc_ops->mpo_ ## check (args), \ 278 error); \ 279 } \ 280 mac_policy_list_unbusy(); \ 281 } \ 282} while (0) 283 284/* 285 * MAC_GRANT performs the designated check by walking the policy module list 286 * and checking with each as to how it feels about the request. Unlike 287 * MAC_CHECK, it grants if any policies return '0', and otherwise returns 288 * EPERM. Note that it returns its value via 'error' in the scope of the 289 * caller. 290 */ 291#define MAC_GRANT(check, args...) do { \ 292 struct mac_policy_conf *mpc; \ 293 int entrycount; \ 294 \ 295 error = EPERM; \ 296 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 297 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 298 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 299 error = 0; \ 300 } \ 301 } \ 302 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 303 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 304 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 305 if (mpc->mpc_ops->mpo_ ## check (args) \ 306 == 0) \ 307 error = 0; \ 308 } \ 309 } \ 310 mac_policy_list_unbusy(); \ 311 } \ 312} while (0) 313 314/* 315 * MAC_BOOLEAN performs the designated boolean composition by walking the 316 * module list, invoking each instance of the operation, and combining the 317 * results using the passed C operator. Note that it returns its value via 318 * 'result' in the scope of the caller, which should be initialized by the 319 * caller in a meaningful way to get a meaningful result. 320 */ 321#define MAC_BOOLEAN(operation, composition, args...) do { \ 322 struct mac_policy_conf *mpc; \ 323 int entrycount; \ 324 \ 325 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 326 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 327 result = result composition \ 328 mpc->mpc_ops->mpo_ ## operation (args); \ 329 } \ 330 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 331 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 332 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 333 result = result composition \ 334 mpc->mpc_ops->mpo_ ## operation \ 335 (args); \ 336 } \ 337 mac_policy_list_unbusy(); \ 338 } \ 339} while (0) 340 341/* 342 * MAC_EXTERNALIZE queries each policy to see if it can generate an 343 * externalized version of a label element by name. Policies declare whether 344 * they have matched a particular element name, parsed from the string by 345 * MAC_EXTERNALIZE, and an error is returned if any element is matched by no 346 * policy. 347 */ 348#define MAC_EXTERNALIZE(type, label, elementlist, outbuf, \ 349 outbuflen) do { \ 350 int claimed, first, ignorenotfound, savedlen; \ 351 char *element_name, *element_temp; \ 352 struct sbuf sb; \ 353 \ 354 error = 0; \ 355 first = 1; \ 356 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 357 element_temp = elementlist; \ 358 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 359 if (element_name[0] == '?') { \ 360 element_name++; \ 361 ignorenotfound = 1; \ 362 } else \ 363 ignorenotfound = 0; \ 364 savedlen = sbuf_len(&sb); \ 365 if (first) \ 366 error = sbuf_printf(&sb, "%s/", element_name); \ 367 else \ 368 error = sbuf_printf(&sb, ",%s/", element_name); \ 369 if (error == -1) { \ 370 error = EINVAL; /* XXX: E2BIG? */ \ 371 break; \ 372 } \ 373 claimed = 0; \ 374 MAC_CHECK(type ## _externalize_label, label, \ 375 element_name, &sb, &claimed); \ 376 if (error) \ 377 break; \ 378 if (claimed == 0 && ignorenotfound) { \ 379 /* Revert last label name. */ \ 380 sbuf_setpos(&sb, savedlen); \ 381 } else if (claimed != 1) { \ 382 error = EINVAL; /* XXX: ENOLABEL? */ \ 383 break; \ 384 } else { \ 385 first = 0; \ 386 } \ 387 } \ 388 sbuf_finish(&sb); \ 389} while (0) 390 391/* 392 * MAC_INTERNALIZE presents parsed element names and data to each policy to 393 * see if any is willing to claim it and internalize the label data. If no 394 * policies match, an error is returned. 395 */ 396#define MAC_INTERNALIZE(type, label, instring) do { \ 397 char *element, *element_name, *element_data; \ 398 int claimed; \ 399 \ 400 error = 0; \ 401 element = instring; \ 402 while ((element_name = strsep(&element, ",")) != NULL) { \ 403 element_data = element_name; \ 404 element_name = strsep(&element_data, "/"); \ 405 if (element_data == NULL) { \ 406 error = EINVAL; \ 407 break; \ 408 } \ 409 claimed = 0; \ 410 MAC_CHECK(type ## _internalize_label, label, \ 411 element_name, element_data, &claimed); \ 412 if (error) \ 413 break; \ 414 if (claimed != 1) { \ 415 /* XXXMAC: Another error here? */ \ 416 error = EINVAL; \ 417 break; \ 418 } \ 419 } \ 420} while (0) 421 422/* 423 * MAC_PERFORM performs the designated operation by walking the policy module 424 * list and invoking that operation for each policy. 425 */ 426#define MAC_PERFORM(operation, args...) do { \ 427 struct mac_policy_conf *mpc; \ 428 int entrycount; \ 429 \ 430 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 431 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 432 mpc->mpc_ops->mpo_ ## operation (args); \ 433 } \ 434 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 435 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 436 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 437 mpc->mpc_ops->mpo_ ## operation (args); \ 438 } \ 439 mac_policy_list_unbusy(); \ 440 } \ 441} while (0) 442 443#endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 444