mac_internal.h revision 182063
1/*- 2 * Copyright (c) 1999-2002, 2006 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 * All rights reserved. 8 * 9 * This software was developed by Robert Watson and Ilmar Habibulin for the 10 * TrustedBSD Project. 11 * 12 * This software was developed for the FreeBSD Project in part by Network 13 * Associates Laboratories, the Security Research Division of Network 14 * Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), 15 * as part of the DARPA CHATS research program. 16 * 17 * This software was developed by Robert N. M. Watson for the TrustedBSD 18 * Project under contract to nCircle Network Security, Inc. 19 * 20 * This software was enhanced by SPARTA ISSO under SPAWAR contract 21 * N66001-04-C-6019 ("SEFOS"). 22 * 23 * Redistribution and use in source and binary forms, with or without 24 * modification, are permitted provided that the following conditions 25 * are met: 26 * 1. Redistributions of source code must retain the above copyright 27 * notice, this list of conditions and the following disclaimer. 28 * 2. Redistributions in binary form must reproduce the above copyright 29 * notice, this list of conditions and the following disclaimer in the 30 * documentation and/or other materials provided with the distribution. 31 * 32 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 33 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 34 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 35 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 36 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 37 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 38 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 39 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 40 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 41 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 42 * SUCH DAMAGE. 43 * 44 * $FreeBSD: head/sys/security/mac/mac_internal.h 182063 2008-08-23 15:26:36Z rwatson $ 45 */ 46 47#ifndef _SECURITY_MAC_MAC_INTERNAL_H_ 48#define _SECURITY_MAC_MAC_INTERNAL_H_ 49 50#ifndef _KERNEL 51#error "no user-serviceable parts inside" 52#endif 53 54/* 55 * MAC Framework sysctl namespace. 56 */ 57#ifdef SYSCTL_DECL 58SYSCTL_DECL(_security_mac); 59#endif /* SYSCTL_DECL */ 60 61/* 62 * MAC Framework global types and typedefs. 63 */ 64LIST_HEAD(mac_policy_list_head, mac_policy_conf); 65#ifdef MALLOC_DECLARE 66MALLOC_DECLARE(M_MACTEMP); 67#endif 68 69/* 70 * MAC labels -- in-kernel storage format. 71 * 72 * In general, struct label pointers are embedded in kernel data structures 73 * representing objects that may be labeled (and protected). Struct label is 74 * opaque to both kernel services that invoke the MAC Framework and MAC 75 * policy modules. In particular, we do not wish to encode the layout of the 76 * label structure into any ABIs. Historically, the slot array contained 77 * unions of {long, void} but now contains uintptr_t. 78 */ 79#define MAC_MAX_SLOTS 4 80#define MAC_FLAG_INITIALIZED 0x0000001 /* Is initialized for use. */ 81struct label { 82 int l_flags; 83 intptr_t l_perpolicy[MAC_MAX_SLOTS]; 84}; 85 86/* 87 * MAC Framework global variables. 88 */ 89extern struct mac_policy_list_head mac_policy_list; 90extern struct mac_policy_list_head mac_static_policy_list; 91extern uint64_t mac_labeled; 92extern struct mtx mac_ifnet_mtx; 93 94/* 95 * MAC Framework infrastructure functions. 96 */ 97int mac_error_select(int error1, int error2); 98 99void mac_policy_grab_exclusive(void); 100void mac_policy_assert_exclusive(void); 101void mac_policy_release_exclusive(void); 102void mac_policy_list_busy(void); 103int mac_policy_list_conditional_busy(void); 104void mac_policy_list_unbusy(void); 105 106struct label *mac_labelzone_alloc(int flags); 107void mac_labelzone_free(struct label *label); 108void mac_labelzone_init(void); 109 110void mac_init_label(struct label *label); 111void mac_destroy_label(struct label *label); 112int mac_check_structmac_consistent(struct mac *mac); 113int mac_allocate_slot(void); 114 115#define MAC_IFNET_LOCK(ifp) mtx_lock(&mac_ifnet_mtx) 116#define MAC_IFNET_UNLOCK(ifp) mtx_unlock(&mac_ifnet_mtx) 117 118/* 119 * MAC Framework per-object type functions. It's not yet clear how the 120 * namespaces, etc, should work for these, so for now, sort by object type. 121 */ 122struct label *mac_cred_label_alloc(void); 123void mac_cred_label_free(struct label *label); 124struct label *mac_pipe_label_alloc(void); 125void mac_pipe_label_free(struct label *label); 126struct label *mac_socket_label_alloc(int flag); 127void mac_socket_label_free(struct label *label); 128struct label *mac_vnode_label_alloc(void); 129void mac_vnode_label_free(struct label *label); 130 131int mac_cred_check_relabel(struct ucred *cred, struct label *newlabel); 132int mac_cred_externalize_label(struct label *label, char *elements, 133 char *outbuf, size_t outbuflen); 134int mac_cred_internalize_label(struct label *label, char *string); 135void mac_cred_relabel(struct ucred *cred, struct label *newlabel); 136 137struct label *mac_mbuf_to_label(struct mbuf *m); 138 139void mac_pipe_copy_label(struct label *src, struct label *dest); 140int mac_pipe_externalize_label(struct label *label, char *elements, 141 char *outbuf, size_t outbuflen); 142int mac_pipe_internalize_label(struct label *label, char *string); 143 144int mac_socket_label_set(struct ucred *cred, struct socket *so, 145 struct label *label); 146void mac_socket_copy_label(struct label *src, struct label *dest); 147int mac_socket_externalize_label(struct label *label, char *elements, 148 char *outbuf, size_t outbuflen); 149int mac_socket_internalize_label(struct label *label, char *string); 150 151int mac_vnode_externalize_label(struct label *label, char *elements, 152 char *outbuf, size_t outbuflen); 153int mac_vnode_internalize_label(struct label *label, char *string); 154void mac_vnode_check_mmap_downgrade(struct ucred *cred, struct vnode *vp, 155 int *prot); 156int vn_setlabel(struct vnode *vp, struct label *intlabel, 157 struct ucred *cred); 158 159/* 160 * MAC_CHECK performs the designated check by walking the policy module list 161 * and checking with each as to how it feels about the request. Note that it 162 * returns its value via 'error' in the scope of the caller. 163 */ 164#define MAC_CHECK(check, args...) do { \ 165 struct mac_policy_conf *mpc; \ 166 int entrycount; \ 167 \ 168 error = 0; \ 169 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 170 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 171 error = mac_error_select( \ 172 mpc->mpc_ops->mpo_ ## check (args), \ 173 error); \ 174 } \ 175 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 176 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 177 if (mpc->mpc_ops->mpo_ ## check != NULL) \ 178 error = mac_error_select( \ 179 mpc->mpc_ops->mpo_ ## check (args), \ 180 error); \ 181 } \ 182 mac_policy_list_unbusy(); \ 183 } \ 184} while (0) 185 186/* 187 * MAC_GRANT performs the designated check by walking the policy module list 188 * and checking with each as to how it feels about the request. Unlike 189 * MAC_CHECK, it grants if any policies return '0', and otherwise returns 190 * EPERM. Note that it returns its value via 'error' in the scope of the 191 * caller. 192 */ 193#define MAC_GRANT(check, args...) do { \ 194 struct mac_policy_conf *mpc; \ 195 int entrycount; \ 196 \ 197 error = EPERM; \ 198 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 199 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 200 if (mpc->mpc_ops->mpo_ ## check(args) == 0) \ 201 error = 0; \ 202 } \ 203 } \ 204 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 205 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 206 if (mpc->mpc_ops->mpo_ ## check != NULL) { \ 207 if (mpc->mpc_ops->mpo_ ## check (args) \ 208 == 0) \ 209 error = 0; \ 210 } \ 211 } \ 212 mac_policy_list_unbusy(); \ 213 } \ 214} while (0) 215 216/* 217 * MAC_BOOLEAN performs the designated boolean composition by walking the 218 * module list, invoking each instance of the operation, and combining the 219 * results using the passed C operator. Note that it returns its value via 220 * 'result' in the scope of the caller, which should be initialized by the 221 * caller in a meaningful way to get a meaningful result. 222 */ 223#define MAC_BOOLEAN(operation, composition, args...) do { \ 224 struct mac_policy_conf *mpc; \ 225 int entrycount; \ 226 \ 227 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 228 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 229 result = result composition \ 230 mpc->mpc_ops->mpo_ ## operation (args); \ 231 } \ 232 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 233 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 234 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 235 result = result composition \ 236 mpc->mpc_ops->mpo_ ## operation \ 237 (args); \ 238 } \ 239 mac_policy_list_unbusy(); \ 240 } \ 241} while (0) 242 243/* 244 * MAC_EXTERNALIZE queries each policy to see if it can generate an 245 * externalized version of a label element by name. Policies declare whether 246 * they have matched a particular element name, parsed from the string by 247 * MAC_EXTERNALIZE, and an error is returned if any element is matched by no 248 * policy. 249 */ 250#define MAC_EXTERNALIZE(type, label, elementlist, outbuf, \ 251 outbuflen) do { \ 252 int claimed, first, ignorenotfound, savedlen; \ 253 char *element_name, *element_temp; \ 254 struct sbuf sb; \ 255 \ 256 error = 0; \ 257 first = 1; \ 258 sbuf_new(&sb, outbuf, outbuflen, SBUF_FIXEDLEN); \ 259 element_temp = elementlist; \ 260 while ((element_name = strsep(&element_temp, ",")) != NULL) { \ 261 if (element_name[0] == '?') { \ 262 element_name++; \ 263 ignorenotfound = 1; \ 264 } else \ 265 ignorenotfound = 0; \ 266 savedlen = sbuf_len(&sb); \ 267 if (first) \ 268 error = sbuf_printf(&sb, "%s/", element_name); \ 269 else \ 270 error = sbuf_printf(&sb, ",%s/", element_name); \ 271 if (error == -1) { \ 272 error = EINVAL; /* XXX: E2BIG? */ \ 273 break; \ 274 } \ 275 claimed = 0; \ 276 MAC_CHECK(type ## _externalize_label, label, \ 277 element_name, &sb, &claimed); \ 278 if (error) \ 279 break; \ 280 if (claimed == 0 && ignorenotfound) { \ 281 /* Revert last label name. */ \ 282 sbuf_setpos(&sb, savedlen); \ 283 } else if (claimed != 1) { \ 284 error = EINVAL; /* XXX: ENOLABEL? */ \ 285 break; \ 286 } else { \ 287 first = 0; \ 288 } \ 289 } \ 290 sbuf_finish(&sb); \ 291} while (0) 292 293/* 294 * MAC_INTERNALIZE presents parsed element names and data to each policy to 295 * see if any is willing to claim it and internalize the label data. If no 296 * policies match, an error is returned. 297 */ 298#define MAC_INTERNALIZE(type, label, instring) do { \ 299 char *element, *element_name, *element_data; \ 300 int claimed; \ 301 \ 302 error = 0; \ 303 element = instring; \ 304 while ((element_name = strsep(&element, ",")) != NULL) { \ 305 element_data = element_name; \ 306 element_name = strsep(&element_data, "/"); \ 307 if (element_data == NULL) { \ 308 error = EINVAL; \ 309 break; \ 310 } \ 311 claimed = 0; \ 312 MAC_CHECK(type ## _internalize_label, label, \ 313 element_name, element_data, &claimed); \ 314 if (error) \ 315 break; \ 316 if (claimed != 1) { \ 317 /* XXXMAC: Another error here? */ \ 318 error = EINVAL; \ 319 break; \ 320 } \ 321 } \ 322} while (0) 323 324/* 325 * MAC_PERFORM performs the designated operation by walking the policy module 326 * list and invoking that operation for each policy. 327 */ 328#define MAC_PERFORM(operation, args...) do { \ 329 struct mac_policy_conf *mpc; \ 330 int entrycount; \ 331 \ 332 LIST_FOREACH(mpc, &mac_static_policy_list, mpc_list) { \ 333 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 334 mpc->mpc_ops->mpo_ ## operation (args); \ 335 } \ 336 if ((entrycount = mac_policy_list_conditional_busy()) != 0) { \ 337 LIST_FOREACH(mpc, &mac_policy_list, mpc_list) { \ 338 if (mpc->mpc_ops->mpo_ ## operation != NULL) \ 339 mpc->mpc_ops->mpo_ ## operation (args); \ 340 } \ 341 mac_policy_list_unbusy(); \ 342 } \ 343} while (0) 344 345#endif /* !_SECURITY_MAC_MAC_INTERNAL_H_ */ 346