1 /* 2 * Implementation of the security services. 3 * 4 * Authors : Stephen Smalley, <sds@tycho.nsa.gov> 5 * James Morris <jmorris@redhat.com> 6 * 7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> 8 * 9 * Support for enhanced MLS infrastructure. 10 * Support for context based audit filters. 11 * 12 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> 13 * 14 * Added conditional policy language extensions 15 * 16 * Updated: Hewlett-Packard <paul@paul-moore.com> 17 * 18 * Added support for NetLabel 19 * Added support for the policy capability bitmap 20 * 21 * Updated: Chad Sellers <csellers@tresys.com> 22 * 23 * Added validation of kernel classes and permissions 24 * 25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com> 26 * 27 * Added support for bounds domain and audit messaged on masked permissions 28 * 29 * Updated: Guido Trentalancia <guido@trentalancia.com> 30 * 31 * Added support for runtime switching of the policy type 32 * 33 * Copyright (C) 2008, 2009 NEC Corporation 34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. 36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC 37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> 38 * This program is free software; you can redistribute it and/or modify 39 * it under the terms of the GNU General Public License as published by 40 * the Free Software Foundation, version 2. 41 */ 42 #include <linux/kernel.h> 43 #include <linux/slab.h> 44 #include <linux/string.h> 45 #include <linux/spinlock.h> 46 #include <linux/rcupdate.h> 47 #include <linux/errno.h> 48 #include <linux/in.h> 49 #include <linux/sched.h> 50 #include <linux/audit.h> 51 #include <linux/mutex.h> 52 #include <linux/selinux.h> 53 #include <linux/flex_array.h> 54 #include <linux/vmalloc.h> 55 #include <net/netlabel.h> 56 57 #include "flask.h" 58 #include "avc.h" 59 #include "avc_ss.h" 60 #include "security.h" 61 #include "context.h" 62 #include "policydb.h" 63 #include "sidtab.h" 64 #include "services.h" 65 #include "conditional.h" 66 #include "mls.h" 67 #include "objsec.h" 68 #include "netlabel.h" 69 #include "xfrm.h" 70 #include "ebitmap.h" 71 #include "audit.h" 72 73 /* Policy capability names */ 74 char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = { 75 "network_peer_controls", 76 "open_perms", 77 "extended_socket_class", 78 "always_check_network", 79 "cgroup_seclabel", 80 "nnp_nosuid_transition" 81 }; 82 83 static struct selinux_ss selinux_ss; 84 85 void selinux_ss_init(struct selinux_ss **ss) 86 { 87 rwlock_init(&selinux_ss.policy_rwlock); 88 mutex_init(&selinux_ss.status_lock); 89 *ss = &selinux_ss; 90 } 91 92 /* Forward declaration. */ 93 static int context_struct_to_string(struct policydb *policydb, 94 struct context *context, 95 char **scontext, 96 u32 *scontext_len); 97 98 static void context_struct_compute_av(struct policydb *policydb, 99 struct context *scontext, 100 struct context *tcontext, 101 u16 tclass, 102 struct av_decision *avd, 103 struct extended_perms *xperms); 104 105 static int selinux_set_mapping(struct policydb *pol, 106 struct security_class_mapping *map, 107 struct selinux_map *out_map) 108 { 109 u16 i, j; 110 unsigned k; 111 bool print_unknown_handle = false; 112 113 /* Find number of classes in the input mapping */ 114 if (!map) 115 return -EINVAL; 116 i = 0; 117 while (map[i].name) 118 i++; 119 120 /* Allocate space for the class records, plus one for class zero */ 121 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC); 122 if (!out_map->mapping) 123 return -ENOMEM; 124 125 /* Store the raw class and permission values */ 126 j = 0; 127 while (map[j].name) { 128 struct security_class_mapping *p_in = map + (j++); 129 struct selinux_mapping *p_out = out_map->mapping + j; 130 131 /* An empty class string skips ahead */ 132 if (!strcmp(p_in->name, "")) { 133 p_out->num_perms = 0; 134 continue; 135 } 136 137 p_out->value = string_to_security_class(pol, p_in->name); 138 if (!p_out->value) { 139 printk(KERN_INFO 140 "SELinux: Class %s not defined in policy.\n", 141 p_in->name); 142 if (pol->reject_unknown) 143 goto err; 144 p_out->num_perms = 0; 145 print_unknown_handle = true; 146 continue; 147 } 148 149 k = 0; 150 while (p_in->perms[k]) { 151 /* An empty permission string skips ahead */ 152 if (!*p_in->perms[k]) { 153 k++; 154 continue; 155 } 156 p_out->perms[k] = string_to_av_perm(pol, p_out->value, 157 p_in->perms[k]); 158 if (!p_out->perms[k]) { 159 printk(KERN_INFO 160 "SELinux: Permission %s in class %s not defined in policy.\n", 161 p_in->perms[k], p_in->name); 162 if (pol->reject_unknown) 163 goto err; 164 print_unknown_handle = true; 165 } 166 167 k++; 168 } 169 p_out->num_perms = k; 170 } 171 172 if (print_unknown_handle) 173 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n", 174 pol->allow_unknown ? "allowed" : "denied"); 175 176 out_map->size = i; 177 return 0; 178 err: 179 kfree(out_map->mapping); 180 out_map->mapping = NULL; 181 return -EINVAL; 182 } 183 184 /* 185 * Get real, policy values from mapped values 186 */ 187 188 static u16 unmap_class(struct selinux_map *map, u16 tclass) 189 { 190 if (tclass < map->size) 191 return map->mapping[tclass].value; 192 193 return tclass; 194 } 195 196 /* 197 * Get kernel value for class from its policy value 198 */ 199 static u16 map_class(struct selinux_map *map, u16 pol_value) 200 { 201 u16 i; 202 203 for (i = 1; i < map->size; i++) { 204 if (map->mapping[i].value == pol_value) 205 return i; 206 } 207 208 return SECCLASS_NULL; 209 } 210 211 static void map_decision(struct selinux_map *map, 212 u16 tclass, struct av_decision *avd, 213 int allow_unknown) 214 { 215 if (tclass < map->size) { 216 struct selinux_mapping *mapping = &map->mapping[tclass]; 217 unsigned int i, n = mapping->num_perms; 218 u32 result; 219 220 for (i = 0, result = 0; i < n; i++) { 221 if (avd->allowed & mapping->perms[i]) 222 result |= 1<<i; 223 if (allow_unknown && !mapping->perms[i]) 224 result |= 1<<i; 225 } 226 avd->allowed = result; 227 228 for (i = 0, result = 0; i < n; i++) 229 if (avd->auditallow & mapping->perms[i]) 230 result |= 1<<i; 231 avd->auditallow = result; 232 233 for (i = 0, result = 0; i < n; i++) { 234 if (avd->auditdeny & mapping->perms[i]) 235 result |= 1<<i; 236 if (!allow_unknown && !mapping->perms[i]) 237 result |= 1<<i; 238 } 239 /* 240 * In case the kernel has a bug and requests a permission 241 * between num_perms and the maximum permission number, we 242 * should audit that denial 243 */ 244 for (; i < (sizeof(u32)*8); i++) 245 result |= 1<<i; 246 avd->auditdeny = result; 247 } 248 } 249 250 int security_mls_enabled(struct selinux_state *state) 251 { 252 struct policydb *p = &state->ss->policydb; 253 254 return p->mls_enabled; 255 } 256 257 /* 258 * Return the boolean value of a constraint expression 259 * when it is applied to the specified source and target 260 * security contexts. 261 * 262 * xcontext is a special beast... It is used by the validatetrans rules 263 * only. For these rules, scontext is the context before the transition, 264 * tcontext is the context after the transition, and xcontext is the context 265 * of the process performing the transition. All other callers of 266 * constraint_expr_eval should pass in NULL for xcontext. 267 */ 268 static int constraint_expr_eval(struct policydb *policydb, 269 struct context *scontext, 270 struct context *tcontext, 271 struct context *xcontext, 272 struct constraint_expr *cexpr) 273 { 274 u32 val1, val2; 275 struct context *c; 276 struct role_datum *r1, *r2; 277 struct mls_level *l1, *l2; 278 struct constraint_expr *e; 279 int s[CEXPR_MAXDEPTH]; 280 int sp = -1; 281 282 for (e = cexpr; e; e = e->next) { 283 switch (e->expr_type) { 284 case CEXPR_NOT: 285 BUG_ON(sp < 0); 286 s[sp] = !s[sp]; 287 break; 288 case CEXPR_AND: 289 BUG_ON(sp < 1); 290 sp--; 291 s[sp] &= s[sp + 1]; 292 break; 293 case CEXPR_OR: 294 BUG_ON(sp < 1); 295 sp--; 296 s[sp] |= s[sp + 1]; 297 break; 298 case CEXPR_ATTR: 299 if (sp == (CEXPR_MAXDEPTH - 1)) 300 return 0; 301 switch (e->attr) { 302 case CEXPR_USER: 303 val1 = scontext->user; 304 val2 = tcontext->user; 305 break; 306 case CEXPR_TYPE: 307 val1 = scontext->type; 308 val2 = tcontext->type; 309 break; 310 case CEXPR_ROLE: 311 val1 = scontext->role; 312 val2 = tcontext->role; 313 r1 = policydb->role_val_to_struct[val1 - 1]; 314 r2 = policydb->role_val_to_struct[val2 - 1]; 315 switch (e->op) { 316 case CEXPR_DOM: 317 s[++sp] = ebitmap_get_bit(&r1->dominates, 318 val2 - 1); 319 continue; 320 case CEXPR_DOMBY: 321 s[++sp] = ebitmap_get_bit(&r2->dominates, 322 val1 - 1); 323 continue; 324 case CEXPR_INCOMP: 325 s[++sp] = (!ebitmap_get_bit(&r1->dominates, 326 val2 - 1) && 327 !ebitmap_get_bit(&r2->dominates, 328 val1 - 1)); 329 continue; 330 default: 331 break; 332 } 333 break; 334 case CEXPR_L1L2: 335 l1 = &(scontext->range.level[0]); 336 l2 = &(tcontext->range.level[0]); 337 goto mls_ops; 338 case CEXPR_L1H2: 339 l1 = &(scontext->range.level[0]); 340 l2 = &(tcontext->range.level[1]); 341 goto mls_ops; 342 case CEXPR_H1L2: 343 l1 = &(scontext->range.level[1]); 344 l2 = &(tcontext->range.level[0]); 345 goto mls_ops; 346 case CEXPR_H1H2: 347 l1 = &(scontext->range.level[1]); 348 l2 = &(tcontext->range.level[1]); 349 goto mls_ops; 350 case CEXPR_L1H1: 351 l1 = &(scontext->range.level[0]); 352 l2 = &(scontext->range.level[1]); 353 goto mls_ops; 354 case CEXPR_L2H2: 355 l1 = &(tcontext->range.level[0]); 356 l2 = &(tcontext->range.level[1]); 357 goto mls_ops; 358 mls_ops: 359 switch (e->op) { 360 case CEXPR_EQ: 361 s[++sp] = mls_level_eq(l1, l2); 362 continue; 363 case CEXPR_NEQ: 364 s[++sp] = !mls_level_eq(l1, l2); 365 continue; 366 case CEXPR_DOM: 367 s[++sp] = mls_level_dom(l1, l2); 368 continue; 369 case CEXPR_DOMBY: 370 s[++sp] = mls_level_dom(l2, l1); 371 continue; 372 case CEXPR_INCOMP: 373 s[++sp] = mls_level_incomp(l2, l1); 374 continue; 375 default: 376 BUG(); 377 return 0; 378 } 379 break; 380 default: 381 BUG(); 382 return 0; 383 } 384 385 switch (e->op) { 386 case CEXPR_EQ: 387 s[++sp] = (val1 == val2); 388 break; 389 case CEXPR_NEQ: 390 s[++sp] = (val1 != val2); 391 break; 392 default: 393 BUG(); 394 return 0; 395 } 396 break; 397 case CEXPR_NAMES: 398 if (sp == (CEXPR_MAXDEPTH-1)) 399 return 0; 400 c = scontext; 401 if (e->attr & CEXPR_TARGET) 402 c = tcontext; 403 else if (e->attr & CEXPR_XTARGET) { 404 c = xcontext; 405 if (!c) { 406 BUG(); 407 return 0; 408 } 409 } 410 if (e->attr & CEXPR_USER) 411 val1 = c->user; 412 else if (e->attr & CEXPR_ROLE) 413 val1 = c->role; 414 else if (e->attr & CEXPR_TYPE) 415 val1 = c->type; 416 else { 417 BUG(); 418 return 0; 419 } 420 421 switch (e->op) { 422 case CEXPR_EQ: 423 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); 424 break; 425 case CEXPR_NEQ: 426 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); 427 break; 428 default: 429 BUG(); 430 return 0; 431 } 432 break; 433 default: 434 BUG(); 435 return 0; 436 } 437 } 438 439 BUG_ON(sp != 0); 440 return s[0]; 441 } 442 443 /* 444 * security_dump_masked_av - dumps masked permissions during 445 * security_compute_av due to RBAC, MLS/Constraint and Type bounds. 446 */ 447 static int dump_masked_av_helper(void *k, void *d, void *args) 448 { 449 struct perm_datum *pdatum = d; 450 char **permission_names = args; 451 452 BUG_ON(pdatum->value < 1 || pdatum->value > 32); 453 454 permission_names[pdatum->value - 1] = (char *)k; 455 456 return 0; 457 } 458 459 static void security_dump_masked_av(struct policydb *policydb, 460 struct context *scontext, 461 struct context *tcontext, 462 u16 tclass, 463 u32 permissions, 464 const char *reason) 465 { 466 struct common_datum *common_dat; 467 struct class_datum *tclass_dat; 468 struct audit_buffer *ab; 469 char *tclass_name; 470 char *scontext_name = NULL; 471 char *tcontext_name = NULL; 472 char *permission_names[32]; 473 int index; 474 u32 length; 475 bool need_comma = false; 476 477 if (!permissions) 478 return; 479 480 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1); 481 tclass_dat = policydb->class_val_to_struct[tclass - 1]; 482 common_dat = tclass_dat->comdatum; 483 484 /* init permission_names */ 485 if (common_dat && 486 hashtab_map(common_dat->permissions.table, 487 dump_masked_av_helper, permission_names) < 0) 488 goto out; 489 490 if (hashtab_map(tclass_dat->permissions.table, 491 dump_masked_av_helper, permission_names) < 0) 492 goto out; 493 494 /* get scontext/tcontext in text form */ 495 if (context_struct_to_string(policydb, scontext, 496 &scontext_name, &length) < 0) 497 goto out; 498 499 if (context_struct_to_string(policydb, tcontext, 500 &tcontext_name, &length) < 0) 501 goto out; 502 503 /* audit a message */ 504 ab = audit_log_start(audit_context(), 505 GFP_ATOMIC, AUDIT_SELINUX_ERR); 506 if (!ab) 507 goto out; 508 509 audit_log_format(ab, "op=security_compute_av reason=%s " 510 "scontext=%s tcontext=%s tclass=%s perms=", 511 reason, scontext_name, tcontext_name, tclass_name); 512 513 for (index = 0; index < 32; index++) { 514 u32 mask = (1 << index); 515 516 if ((mask & permissions) == 0) 517 continue; 518 519 audit_log_format(ab, "%s%s", 520 need_comma ? "," : "", 521 permission_names[index] 522 ? permission_names[index] : "????"); 523 need_comma = true; 524 } 525 audit_log_end(ab); 526 out: 527 /* release scontext/tcontext */ 528 kfree(tcontext_name); 529 kfree(scontext_name); 530 531 return; 532 } 533 534 /* 535 * security_boundary_permission - drops violated permissions 536 * on boundary constraint. 537 */ 538 static void type_attribute_bounds_av(struct policydb *policydb, 539 struct context *scontext, 540 struct context *tcontext, 541 u16 tclass, 542 struct av_decision *avd) 543 { 544 struct context lo_scontext; 545 struct context lo_tcontext, *tcontextp = tcontext; 546 struct av_decision lo_avd; 547 struct type_datum *source; 548 struct type_datum *target; 549 u32 masked = 0; 550 551 source = flex_array_get_ptr(policydb->type_val_to_struct_array, 552 scontext->type - 1); 553 BUG_ON(!source); 554 555 if (!source->bounds) 556 return; 557 558 target = flex_array_get_ptr(policydb->type_val_to_struct_array, 559 tcontext->type - 1); 560 BUG_ON(!target); 561 562 memset(&lo_avd, 0, sizeof(lo_avd)); 563 564 memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); 565 lo_scontext.type = source->bounds; 566 567 if (target->bounds) { 568 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); 569 lo_tcontext.type = target->bounds; 570 tcontextp = &lo_tcontext; 571 } 572 573 context_struct_compute_av(policydb, &lo_scontext, 574 tcontextp, 575 tclass, 576 &lo_avd, 577 NULL); 578 579 masked = ~lo_avd.allowed & avd->allowed; 580 581 if (likely(!masked)) 582 return; /* no masked permission */ 583 584 /* mask violated permissions */ 585 avd->allowed &= ~masked; 586 587 /* audit masked permissions */ 588 security_dump_masked_av(policydb, scontext, tcontext, 589 tclass, masked, "bounds"); 590 } 591 592 /* 593 * flag which drivers have permissions 594 * only looking for ioctl based extended permssions 595 */ 596 void services_compute_xperms_drivers( 597 struct extended_perms *xperms, 598 struct avtab_node *node) 599 { 600 unsigned int i; 601 602 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 603 /* if one or more driver has all permissions allowed */ 604 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++) 605 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i]; 606 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 607 /* if allowing permissions within a driver */ 608 security_xperm_set(xperms->drivers.p, 609 node->datum.u.xperms->driver); 610 } 611 612 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */ 613 if (node->key.specified & AVTAB_XPERMS_ALLOWED) 614 xperms->len = 1; 615 } 616 617 /* 618 * Compute access vectors and extended permissions based on a context 619 * structure pair for the permissions in a particular class. 620 */ 621 static void context_struct_compute_av(struct policydb *policydb, 622 struct context *scontext, 623 struct context *tcontext, 624 u16 tclass, 625 struct av_decision *avd, 626 struct extended_perms *xperms) 627 { 628 struct constraint_node *constraint; 629 struct role_allow *ra; 630 struct avtab_key avkey; 631 struct avtab_node *node; 632 struct class_datum *tclass_datum; 633 struct ebitmap *sattr, *tattr; 634 struct ebitmap_node *snode, *tnode; 635 unsigned int i, j; 636 637 avd->allowed = 0; 638 avd->auditallow = 0; 639 avd->auditdeny = 0xffffffff; 640 if (xperms) { 641 memset(&xperms->drivers, 0, sizeof(xperms->drivers)); 642 xperms->len = 0; 643 } 644 645 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { 646 if (printk_ratelimit()) 647 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); 648 return; 649 } 650 651 tclass_datum = policydb->class_val_to_struct[tclass - 1]; 652 653 /* 654 * If a specific type enforcement rule was defined for 655 * this permission check, then use it. 656 */ 657 avkey.target_class = tclass; 658 avkey.specified = AVTAB_AV | AVTAB_XPERMS; 659 sattr = flex_array_get(policydb->type_attr_map_array, 660 scontext->type - 1); 661 BUG_ON(!sattr); 662 tattr = flex_array_get(policydb->type_attr_map_array, 663 tcontext->type - 1); 664 BUG_ON(!tattr); 665 ebitmap_for_each_positive_bit(sattr, snode, i) { 666 ebitmap_for_each_positive_bit(tattr, tnode, j) { 667 avkey.source_type = i + 1; 668 avkey.target_type = j + 1; 669 for (node = avtab_search_node(&policydb->te_avtab, 670 &avkey); 671 node; 672 node = avtab_search_node_next(node, avkey.specified)) { 673 if (node->key.specified == AVTAB_ALLOWED) 674 avd->allowed |= node->datum.u.data; 675 else if (node->key.specified == AVTAB_AUDITALLOW) 676 avd->auditallow |= node->datum.u.data; 677 else if (node->key.specified == AVTAB_AUDITDENY) 678 avd->auditdeny &= node->datum.u.data; 679 else if (xperms && (node->key.specified & AVTAB_XPERMS)) 680 services_compute_xperms_drivers(xperms, node); 681 } 682 683 /* Check conditional av table for additional permissions */ 684 cond_compute_av(&policydb->te_cond_avtab, &avkey, 685 avd, xperms); 686 687 } 688 } 689 690 /* 691 * Remove any permissions prohibited by a constraint (this includes 692 * the MLS policy). 693 */ 694 constraint = tclass_datum->constraints; 695 while (constraint) { 696 if ((constraint->permissions & (avd->allowed)) && 697 !constraint_expr_eval(policydb, scontext, tcontext, NULL, 698 constraint->expr)) { 699 avd->allowed &= ~(constraint->permissions); 700 } 701 constraint = constraint->next; 702 } 703 704 /* 705 * If checking process transition permission and the 706 * role is changing, then check the (current_role, new_role) 707 * pair. 708 */ 709 if (tclass == policydb->process_class && 710 (avd->allowed & policydb->process_trans_perms) && 711 scontext->role != tcontext->role) { 712 for (ra = policydb->role_allow; ra; ra = ra->next) { 713 if (scontext->role == ra->role && 714 tcontext->role == ra->new_role) 715 break; 716 } 717 if (!ra) 718 avd->allowed &= ~policydb->process_trans_perms; 719 } 720 721 /* 722 * If the given source and target types have boundary 723 * constraint, lazy checks have to mask any violated 724 * permission and notice it to userspace via audit. 725 */ 726 type_attribute_bounds_av(policydb, scontext, tcontext, 727 tclass, avd); 728 } 729 730 static int security_validtrans_handle_fail(struct selinux_state *state, 731 struct context *ocontext, 732 struct context *ncontext, 733 struct context *tcontext, 734 u16 tclass) 735 { 736 struct policydb *p = &state->ss->policydb; 737 char *o = NULL, *n = NULL, *t = NULL; 738 u32 olen, nlen, tlen; 739 740 if (context_struct_to_string(p, ocontext, &o, &olen)) 741 goto out; 742 if (context_struct_to_string(p, ncontext, &n, &nlen)) 743 goto out; 744 if (context_struct_to_string(p, tcontext, &t, &tlen)) 745 goto out; 746 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, 747 "op=security_validate_transition seresult=denied" 748 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", 749 o, n, t, sym_name(p, SYM_CLASSES, tclass-1)); 750 out: 751 kfree(o); 752 kfree(n); 753 kfree(t); 754 755 if (!enforcing_enabled(state)) 756 return 0; 757 return -EPERM; 758 } 759 760 static int security_compute_validatetrans(struct selinux_state *state, 761 u32 oldsid, u32 newsid, u32 tasksid, 762 u16 orig_tclass, bool user) 763 { 764 struct policydb *policydb; 765 struct sidtab *sidtab; 766 struct context *ocontext; 767 struct context *ncontext; 768 struct context *tcontext; 769 struct class_datum *tclass_datum; 770 struct constraint_node *constraint; 771 u16 tclass; 772 int rc = 0; 773 774 775 if (!state->initialized) 776 return 0; 777 778 read_lock(&state->ss->policy_rwlock); 779 780 policydb = &state->ss->policydb; 781 sidtab = &state->ss->sidtab; 782 783 if (!user) 784 tclass = unmap_class(&state->ss->map, orig_tclass); 785 else 786 tclass = orig_tclass; 787 788 if (!tclass || tclass > policydb->p_classes.nprim) { 789 rc = -EINVAL; 790 goto out; 791 } 792 tclass_datum = policydb->class_val_to_struct[tclass - 1]; 793 794 ocontext = sidtab_search(sidtab, oldsid); 795 if (!ocontext) { 796 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 797 __func__, oldsid); 798 rc = -EINVAL; 799 goto out; 800 } 801 802 ncontext = sidtab_search(sidtab, newsid); 803 if (!ncontext) { 804 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 805 __func__, newsid); 806 rc = -EINVAL; 807 goto out; 808 } 809 810 tcontext = sidtab_search(sidtab, tasksid); 811 if (!tcontext) { 812 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 813 __func__, tasksid); 814 rc = -EINVAL; 815 goto out; 816 } 817 818 constraint = tclass_datum->validatetrans; 819 while (constraint) { 820 if (!constraint_expr_eval(policydb, ocontext, ncontext, 821 tcontext, constraint->expr)) { 822 if (user) 823 rc = -EPERM; 824 else 825 rc = security_validtrans_handle_fail(state, 826 ocontext, 827 ncontext, 828 tcontext, 829 tclass); 830 goto out; 831 } 832 constraint = constraint->next; 833 } 834 835 out: 836 read_unlock(&state->ss->policy_rwlock); 837 return rc; 838 } 839 840 int security_validate_transition_user(struct selinux_state *state, 841 u32 oldsid, u32 newsid, u32 tasksid, 842 u16 tclass) 843 { 844 return security_compute_validatetrans(state, oldsid, newsid, tasksid, 845 tclass, true); 846 } 847 848 int security_validate_transition(struct selinux_state *state, 849 u32 oldsid, u32 newsid, u32 tasksid, 850 u16 orig_tclass) 851 { 852 return security_compute_validatetrans(state, oldsid, newsid, tasksid, 853 orig_tclass, false); 854 } 855 856 /* 857 * security_bounded_transition - check whether the given 858 * transition is directed to bounded, or not. 859 * It returns 0, if @newsid is bounded by @oldsid. 860 * Otherwise, it returns error code. 861 * 862 * @oldsid : current security identifier 863 * @newsid : destinated security identifier 864 */ 865 int security_bounded_transition(struct selinux_state *state, 866 u32 old_sid, u32 new_sid) 867 { 868 struct policydb *policydb; 869 struct sidtab *sidtab; 870 struct context *old_context, *new_context; 871 struct type_datum *type; 872 int index; 873 int rc; 874 875 if (!state->initialized) 876 return 0; 877 878 read_lock(&state->ss->policy_rwlock); 879 880 policydb = &state->ss->policydb; 881 sidtab = &state->ss->sidtab; 882 883 rc = -EINVAL; 884 old_context = sidtab_search(sidtab, old_sid); 885 if (!old_context) { 886 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 887 __func__, old_sid); 888 goto out; 889 } 890 891 rc = -EINVAL; 892 new_context = sidtab_search(sidtab, new_sid); 893 if (!new_context) { 894 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 895 __func__, new_sid); 896 goto out; 897 } 898 899 rc = 0; 900 /* type/domain unchanged */ 901 if (old_context->type == new_context->type) 902 goto out; 903 904 index = new_context->type; 905 while (true) { 906 type = flex_array_get_ptr(policydb->type_val_to_struct_array, 907 index - 1); 908 BUG_ON(!type); 909 910 /* not bounded anymore */ 911 rc = -EPERM; 912 if (!type->bounds) 913 break; 914 915 /* @newsid is bounded by @oldsid */ 916 rc = 0; 917 if (type->bounds == old_context->type) 918 break; 919 920 index = type->bounds; 921 } 922 923 if (rc) { 924 char *old_name = NULL; 925 char *new_name = NULL; 926 u32 length; 927 928 if (!context_struct_to_string(policydb, old_context, 929 &old_name, &length) && 930 !context_struct_to_string(policydb, new_context, 931 &new_name, &length)) { 932 audit_log(audit_context(), 933 GFP_ATOMIC, AUDIT_SELINUX_ERR, 934 "op=security_bounded_transition " 935 "seresult=denied " 936 "oldcontext=%s newcontext=%s", 937 old_name, new_name); 938 } 939 kfree(new_name); 940 kfree(old_name); 941 } 942 out: 943 read_unlock(&state->ss->policy_rwlock); 944 945 return rc; 946 } 947 948 static void avd_init(struct selinux_state *state, struct av_decision *avd) 949 { 950 avd->allowed = 0; 951 avd->auditallow = 0; 952 avd->auditdeny = 0xffffffff; 953 avd->seqno = state->ss->latest_granting; 954 avd->flags = 0; 955 } 956 957 void services_compute_xperms_decision(struct extended_perms_decision *xpermd, 958 struct avtab_node *node) 959 { 960 unsigned int i; 961 962 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 963 if (xpermd->driver != node->datum.u.xperms->driver) 964 return; 965 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 966 if (!security_xperm_test(node->datum.u.xperms->perms.p, 967 xpermd->driver)) 968 return; 969 } else { 970 BUG(); 971 } 972 973 if (node->key.specified == AVTAB_XPERMS_ALLOWED) { 974 xpermd->used |= XPERMS_ALLOWED; 975 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 976 memset(xpermd->allowed->p, 0xff, 977 sizeof(xpermd->allowed->p)); 978 } 979 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 980 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++) 981 xpermd->allowed->p[i] |= 982 node->datum.u.xperms->perms.p[i]; 983 } 984 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) { 985 xpermd->used |= XPERMS_AUDITALLOW; 986 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 987 memset(xpermd->auditallow->p, 0xff, 988 sizeof(xpermd->auditallow->p)); 989 } 990 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 991 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++) 992 xpermd->auditallow->p[i] |= 993 node->datum.u.xperms->perms.p[i]; 994 } 995 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) { 996 xpermd->used |= XPERMS_DONTAUDIT; 997 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 998 memset(xpermd->dontaudit->p, 0xff, 999 sizeof(xpermd->dontaudit->p)); 1000 } 1001 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 1002 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++) 1003 xpermd->dontaudit->p[i] |= 1004 node->datum.u.xperms->perms.p[i]; 1005 } 1006 } else { 1007 BUG(); 1008 } 1009 } 1010 1011 void security_compute_xperms_decision(struct selinux_state *state, 1012 u32 ssid, 1013 u32 tsid, 1014 u16 orig_tclass, 1015 u8 driver, 1016 struct extended_perms_decision *xpermd) 1017 { 1018 struct policydb *policydb; 1019 struct sidtab *sidtab; 1020 u16 tclass; 1021 struct context *scontext, *tcontext; 1022 struct avtab_key avkey; 1023 struct avtab_node *node; 1024 struct ebitmap *sattr, *tattr; 1025 struct ebitmap_node *snode, *tnode; 1026 unsigned int i, j; 1027 1028 xpermd->driver = driver; 1029 xpermd->used = 0; 1030 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p)); 1031 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); 1032 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); 1033 1034 read_lock(&state->ss->policy_rwlock); 1035 if (!state->initialized) 1036 goto allow; 1037 1038 policydb = &state->ss->policydb; 1039 sidtab = &state->ss->sidtab; 1040 1041 scontext = sidtab_search(sidtab, ssid); 1042 if (!scontext) { 1043 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1044 __func__, ssid); 1045 goto out; 1046 } 1047 1048 tcontext = sidtab_search(sidtab, tsid); 1049 if (!tcontext) { 1050 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1051 __func__, tsid); 1052 goto out; 1053 } 1054 1055 tclass = unmap_class(&state->ss->map, orig_tclass); 1056 if (unlikely(orig_tclass && !tclass)) { 1057 if (policydb->allow_unknown) 1058 goto allow; 1059 goto out; 1060 } 1061 1062 1063 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { 1064 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass); 1065 goto out; 1066 } 1067 1068 avkey.target_class = tclass; 1069 avkey.specified = AVTAB_XPERMS; 1070 sattr = flex_array_get(policydb->type_attr_map_array, 1071 scontext->type - 1); 1072 BUG_ON(!sattr); 1073 tattr = flex_array_get(policydb->type_attr_map_array, 1074 tcontext->type - 1); 1075 BUG_ON(!tattr); 1076 ebitmap_for_each_positive_bit(sattr, snode, i) { 1077 ebitmap_for_each_positive_bit(tattr, tnode, j) { 1078 avkey.source_type = i + 1; 1079 avkey.target_type = j + 1; 1080 for (node = avtab_search_node(&policydb->te_avtab, 1081 &avkey); 1082 node; 1083 node = avtab_search_node_next(node, avkey.specified)) 1084 services_compute_xperms_decision(xpermd, node); 1085 1086 cond_compute_xperms(&policydb->te_cond_avtab, 1087 &avkey, xpermd); 1088 } 1089 } 1090 out: 1091 read_unlock(&state->ss->policy_rwlock); 1092 return; 1093 allow: 1094 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); 1095 goto out; 1096 } 1097 1098 /** 1099 * security_compute_av - Compute access vector decisions. 1100 * @ssid: source security identifier 1101 * @tsid: target security identifier 1102 * @tclass: target security class 1103 * @avd: access vector decisions 1104 * @xperms: extended permissions 1105 * 1106 * Compute a set of access vector decisions based on the 1107 * SID pair (@ssid, @tsid) for the permissions in @tclass. 1108 */ 1109 void security_compute_av(struct selinux_state *state, 1110 u32 ssid, 1111 u32 tsid, 1112 u16 orig_tclass, 1113 struct av_decision *avd, 1114 struct extended_perms *xperms) 1115 { 1116 struct policydb *policydb; 1117 struct sidtab *sidtab; 1118 u16 tclass; 1119 struct context *scontext = NULL, *tcontext = NULL; 1120 1121 read_lock(&state->ss->policy_rwlock); 1122 avd_init(state, avd); 1123 xperms->len = 0; 1124 if (!state->initialized) 1125 goto allow; 1126 1127 policydb = &state->ss->policydb; 1128 sidtab = &state->ss->sidtab; 1129 1130 scontext = sidtab_search(sidtab, ssid); 1131 if (!scontext) { 1132 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1133 __func__, ssid); 1134 goto out; 1135 } 1136 1137 /* permissive domain? */ 1138 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type)) 1139 avd->flags |= AVD_FLAGS_PERMISSIVE; 1140 1141 tcontext = sidtab_search(sidtab, tsid); 1142 if (!tcontext) { 1143 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1144 __func__, tsid); 1145 goto out; 1146 } 1147 1148 tclass = unmap_class(&state->ss->map, orig_tclass); 1149 if (unlikely(orig_tclass && !tclass)) { 1150 if (policydb->allow_unknown) 1151 goto allow; 1152 goto out; 1153 } 1154 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, 1155 xperms); 1156 map_decision(&state->ss->map, orig_tclass, avd, 1157 policydb->allow_unknown); 1158 out: 1159 read_unlock(&state->ss->policy_rwlock); 1160 return; 1161 allow: 1162 avd->allowed = 0xffffffff; 1163 goto out; 1164 } 1165 1166 void security_compute_av_user(struct selinux_state *state, 1167 u32 ssid, 1168 u32 tsid, 1169 u16 tclass, 1170 struct av_decision *avd) 1171 { 1172 struct policydb *policydb; 1173 struct sidtab *sidtab; 1174 struct context *scontext = NULL, *tcontext = NULL; 1175 1176 read_lock(&state->ss->policy_rwlock); 1177 avd_init(state, avd); 1178 if (!state->initialized) 1179 goto allow; 1180 1181 policydb = &state->ss->policydb; 1182 sidtab = &state->ss->sidtab; 1183 1184 scontext = sidtab_search(sidtab, ssid); 1185 if (!scontext) { 1186 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1187 __func__, ssid); 1188 goto out; 1189 } 1190 1191 /* permissive domain? */ 1192 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type)) 1193 avd->flags |= AVD_FLAGS_PERMISSIVE; 1194 1195 tcontext = sidtab_search(sidtab, tsid); 1196 if (!tcontext) { 1197 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1198 __func__, tsid); 1199 goto out; 1200 } 1201 1202 if (unlikely(!tclass)) { 1203 if (policydb->allow_unknown) 1204 goto allow; 1205 goto out; 1206 } 1207 1208 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, 1209 NULL); 1210 out: 1211 read_unlock(&state->ss->policy_rwlock); 1212 return; 1213 allow: 1214 avd->allowed = 0xffffffff; 1215 goto out; 1216 } 1217 1218 /* 1219 * Write the security context string representation of 1220 * the context structure `context' into a dynamically 1221 * allocated string of the correct size. Set `*scontext' 1222 * to point to this string and set `*scontext_len' to 1223 * the length of the string. 1224 */ 1225 static int context_struct_to_string(struct policydb *p, 1226 struct context *context, 1227 char **scontext, u32 *scontext_len) 1228 { 1229 char *scontextp; 1230 1231 if (scontext) 1232 *scontext = NULL; 1233 *scontext_len = 0; 1234 1235 if (context->len) { 1236 *scontext_len = context->len; 1237 if (scontext) { 1238 *scontext = kstrdup(context->str, GFP_ATOMIC); 1239 if (!(*scontext)) 1240 return -ENOMEM; 1241 } 1242 return 0; 1243 } 1244 1245 /* Compute the size of the context. */ 1246 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1; 1247 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1; 1248 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1; 1249 *scontext_len += mls_compute_context_len(p, context); 1250 1251 if (!scontext) 1252 return 0; 1253 1254 /* Allocate space for the context; caller must free this space. */ 1255 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1256 if (!scontextp) 1257 return -ENOMEM; 1258 *scontext = scontextp; 1259 1260 /* 1261 * Copy the user name, role name and type name into the context. 1262 */ 1263 scontextp += sprintf(scontextp, "%s:%s:%s", 1264 sym_name(p, SYM_USERS, context->user - 1), 1265 sym_name(p, SYM_ROLES, context->role - 1), 1266 sym_name(p, SYM_TYPES, context->type - 1)); 1267 1268 mls_sid_to_context(p, context, &scontextp); 1269 1270 *scontextp = 0; 1271 1272 return 0; 1273 } 1274 1275 #include "initial_sid_to_string.h" 1276 1277 const char *security_get_initial_sid_context(u32 sid) 1278 { 1279 if (unlikely(sid > SECINITSID_NUM)) 1280 return NULL; 1281 return initial_sid_to_string[sid]; 1282 } 1283 1284 static int security_sid_to_context_core(struct selinux_state *state, 1285 u32 sid, char **scontext, 1286 u32 *scontext_len, int force) 1287 { 1288 struct policydb *policydb; 1289 struct sidtab *sidtab; 1290 struct context *context; 1291 int rc = 0; 1292 1293 if (scontext) 1294 *scontext = NULL; 1295 *scontext_len = 0; 1296 1297 if (!state->initialized) { 1298 if (sid <= SECINITSID_NUM) { 1299 char *scontextp; 1300 1301 *scontext_len = strlen(initial_sid_to_string[sid]) + 1; 1302 if (!scontext) 1303 goto out; 1304 scontextp = kmemdup(initial_sid_to_string[sid], 1305 *scontext_len, GFP_ATOMIC); 1306 if (!scontextp) { 1307 rc = -ENOMEM; 1308 goto out; 1309 } 1310 *scontext = scontextp; 1311 goto out; 1312 } 1313 printk(KERN_ERR "SELinux: %s: called before initial " 1314 "load_policy on unknown SID %d\n", __func__, sid); 1315 rc = -EINVAL; 1316 goto out; 1317 } 1318 read_lock(&state->ss->policy_rwlock); 1319 policydb = &state->ss->policydb; 1320 sidtab = &state->ss->sidtab; 1321 if (force) 1322 context = sidtab_search_force(sidtab, sid); 1323 else 1324 context = sidtab_search(sidtab, sid); 1325 if (!context) { 1326 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1327 __func__, sid); 1328 rc = -EINVAL; 1329 goto out_unlock; 1330 } 1331 rc = context_struct_to_string(policydb, context, scontext, 1332 scontext_len); 1333 out_unlock: 1334 read_unlock(&state->ss->policy_rwlock); 1335 out: 1336 return rc; 1337 1338 } 1339 1340 /** 1341 * security_sid_to_context - Obtain a context for a given SID. 1342 * @sid: security identifier, SID 1343 * @scontext: security context 1344 * @scontext_len: length in bytes 1345 * 1346 * Write the string representation of the context associated with @sid 1347 * into a dynamically allocated string of the correct size. Set @scontext 1348 * to point to this string and set @scontext_len to the length of the string. 1349 */ 1350 int security_sid_to_context(struct selinux_state *state, 1351 u32 sid, char **scontext, u32 *scontext_len) 1352 { 1353 return security_sid_to_context_core(state, sid, scontext, 1354 scontext_len, 0); 1355 } 1356 1357 int security_sid_to_context_force(struct selinux_state *state, u32 sid, 1358 char **scontext, u32 *scontext_len) 1359 { 1360 return security_sid_to_context_core(state, sid, scontext, 1361 scontext_len, 1); 1362 } 1363 1364 /* 1365 * Caveat: Mutates scontext. 1366 */ 1367 static int string_to_context_struct(struct policydb *pol, 1368 struct sidtab *sidtabp, 1369 char *scontext, 1370 u32 scontext_len, 1371 struct context *ctx, 1372 u32 def_sid) 1373 { 1374 struct role_datum *role; 1375 struct type_datum *typdatum; 1376 struct user_datum *usrdatum; 1377 char *scontextp, *p, oldc; 1378 int rc = 0; 1379 1380 context_init(ctx); 1381 1382 /* Parse the security context. */ 1383 1384 rc = -EINVAL; 1385 scontextp = (char *) scontext; 1386 1387 /* Extract the user. */ 1388 p = scontextp; 1389 while (*p && *p != ':') 1390 p++; 1391 1392 if (*p == 0) 1393 goto out; 1394 1395 *p++ = 0; 1396 1397 usrdatum = hashtab_search(pol->p_users.table, scontextp); 1398 if (!usrdatum) 1399 goto out; 1400 1401 ctx->user = usrdatum->value; 1402 1403 /* Extract role. */ 1404 scontextp = p; 1405 while (*p && *p != ':') 1406 p++; 1407 1408 if (*p == 0) 1409 goto out; 1410 1411 *p++ = 0; 1412 1413 role = hashtab_search(pol->p_roles.table, scontextp); 1414 if (!role) 1415 goto out; 1416 ctx->role = role->value; 1417 1418 /* Extract type. */ 1419 scontextp = p; 1420 while (*p && *p != ':') 1421 p++; 1422 oldc = *p; 1423 *p++ = 0; 1424 1425 typdatum = hashtab_search(pol->p_types.table, scontextp); 1426 if (!typdatum || typdatum->attribute) 1427 goto out; 1428 1429 ctx->type = typdatum->value; 1430 1431 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid); 1432 if (rc) 1433 goto out; 1434 1435 rc = -EINVAL; 1436 if ((p - scontext) < scontext_len) 1437 goto out; 1438 1439 /* Check the validity of the new context. */ 1440 if (!policydb_context_isvalid(pol, ctx)) 1441 goto out; 1442 rc = 0; 1443 out: 1444 if (rc) 1445 context_destroy(ctx); 1446 return rc; 1447 } 1448 1449 static int security_context_to_sid_core(struct selinux_state *state, 1450 const char *scontext, u32 scontext_len, 1451 u32 *sid, u32 def_sid, gfp_t gfp_flags, 1452 int force) 1453 { 1454 struct policydb *policydb; 1455 struct sidtab *sidtab; 1456 char *scontext2, *str = NULL; 1457 struct context context; 1458 int rc = 0; 1459 1460 /* An empty security context is never valid. */ 1461 if (!scontext_len) 1462 return -EINVAL; 1463 1464 /* Copy the string to allow changes and ensure a NUL terminator */ 1465 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags); 1466 if (!scontext2) 1467 return -ENOMEM; 1468 1469 if (!state->initialized) { 1470 int i; 1471 1472 for (i = 1; i < SECINITSID_NUM; i++) { 1473 if (!strcmp(initial_sid_to_string[i], scontext2)) { 1474 *sid = i; 1475 goto out; 1476 } 1477 } 1478 *sid = SECINITSID_KERNEL; 1479 goto out; 1480 } 1481 *sid = SECSID_NULL; 1482 1483 if (force) { 1484 /* Save another copy for storing in uninterpreted form */ 1485 rc = -ENOMEM; 1486 str = kstrdup(scontext2, gfp_flags); 1487 if (!str) 1488 goto out; 1489 } 1490 read_lock(&state->ss->policy_rwlock); 1491 policydb = &state->ss->policydb; 1492 sidtab = &state->ss->sidtab; 1493 rc = string_to_context_struct(policydb, sidtab, scontext2, 1494 scontext_len, &context, def_sid); 1495 if (rc == -EINVAL && force) { 1496 context.str = str; 1497 context.len = strlen(str) + 1; 1498 str = NULL; 1499 } else if (rc) 1500 goto out_unlock; 1501 rc = sidtab_context_to_sid(sidtab, &context, sid); 1502 context_destroy(&context); 1503 out_unlock: 1504 read_unlock(&state->ss->policy_rwlock); 1505 out: 1506 kfree(scontext2); 1507 kfree(str); 1508 return rc; 1509 } 1510 1511 /** 1512 * security_context_to_sid - Obtain a SID for a given security context. 1513 * @scontext: security context 1514 * @scontext_len: length in bytes 1515 * @sid: security identifier, SID 1516 * @gfp: context for the allocation 1517 * 1518 * Obtains a SID associated with the security context that 1519 * has the string representation specified by @scontext. 1520 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1521 * memory is available, or 0 on success. 1522 */ 1523 int security_context_to_sid(struct selinux_state *state, 1524 const char *scontext, u32 scontext_len, u32 *sid, 1525 gfp_t gfp) 1526 { 1527 return security_context_to_sid_core(state, scontext, scontext_len, 1528 sid, SECSID_NULL, gfp, 0); 1529 } 1530 1531 int security_context_str_to_sid(struct selinux_state *state, 1532 const char *scontext, u32 *sid, gfp_t gfp) 1533 { 1534 return security_context_to_sid(state, scontext, strlen(scontext), 1535 sid, gfp); 1536 } 1537 1538 /** 1539 * security_context_to_sid_default - Obtain a SID for a given security context, 1540 * falling back to specified default if needed. 1541 * 1542 * @scontext: security context 1543 * @scontext_len: length in bytes 1544 * @sid: security identifier, SID 1545 * @def_sid: default SID to assign on error 1546 * 1547 * Obtains a SID associated with the security context that 1548 * has the string representation specified by @scontext. 1549 * The default SID is passed to the MLS layer to be used to allow 1550 * kernel labeling of the MLS field if the MLS field is not present 1551 * (for upgrading to MLS without full relabel). 1552 * Implicitly forces adding of the context even if it cannot be mapped yet. 1553 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1554 * memory is available, or 0 on success. 1555 */ 1556 int security_context_to_sid_default(struct selinux_state *state, 1557 const char *scontext, u32 scontext_len, 1558 u32 *sid, u32 def_sid, gfp_t gfp_flags) 1559 { 1560 return security_context_to_sid_core(state, scontext, scontext_len, 1561 sid, def_sid, gfp_flags, 1); 1562 } 1563 1564 int security_context_to_sid_force(struct selinux_state *state, 1565 const char *scontext, u32 scontext_len, 1566 u32 *sid) 1567 { 1568 return security_context_to_sid_core(state, scontext, scontext_len, 1569 sid, SECSID_NULL, GFP_KERNEL, 1); 1570 } 1571 1572 static int compute_sid_handle_invalid_context( 1573 struct selinux_state *state, 1574 struct context *scontext, 1575 struct context *tcontext, 1576 u16 tclass, 1577 struct context *newcontext) 1578 { 1579 struct policydb *policydb = &state->ss->policydb; 1580 char *s = NULL, *t = NULL, *n = NULL; 1581 u32 slen, tlen, nlen; 1582 1583 if (context_struct_to_string(policydb, scontext, &s, &slen)) 1584 goto out; 1585 if (context_struct_to_string(policydb, tcontext, &t, &tlen)) 1586 goto out; 1587 if (context_struct_to_string(policydb, newcontext, &n, &nlen)) 1588 goto out; 1589 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, 1590 "op=security_compute_sid invalid_context=%s" 1591 " scontext=%s" 1592 " tcontext=%s" 1593 " tclass=%s", 1594 n, s, t, sym_name(policydb, SYM_CLASSES, tclass-1)); 1595 out: 1596 kfree(s); 1597 kfree(t); 1598 kfree(n); 1599 if (!enforcing_enabled(state)) 1600 return 0; 1601 return -EACCES; 1602 } 1603 1604 static void filename_compute_type(struct policydb *policydb, 1605 struct context *newcontext, 1606 u32 stype, u32 ttype, u16 tclass, 1607 const char *objname) 1608 { 1609 struct filename_trans ft; 1610 struct filename_trans_datum *otype; 1611 1612 /* 1613 * Most filename trans rules are going to live in specific directories 1614 * like /dev or /var/run. This bitmap will quickly skip rule searches 1615 * if the ttype does not contain any rules. 1616 */ 1617 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype)) 1618 return; 1619 1620 ft.stype = stype; 1621 ft.ttype = ttype; 1622 ft.tclass = tclass; 1623 ft.name = objname; 1624 1625 otype = hashtab_search(policydb->filename_trans, &ft); 1626 if (otype) 1627 newcontext->type = otype->otype; 1628 } 1629 1630 static int security_compute_sid(struct selinux_state *state, 1631 u32 ssid, 1632 u32 tsid, 1633 u16 orig_tclass, 1634 u32 specified, 1635 const char *objname, 1636 u32 *out_sid, 1637 bool kern) 1638 { 1639 struct policydb *policydb; 1640 struct sidtab *sidtab; 1641 struct class_datum *cladatum = NULL; 1642 struct context *scontext = NULL, *tcontext = NULL, newcontext; 1643 struct role_trans *roletr = NULL; 1644 struct avtab_key avkey; 1645 struct avtab_datum *avdatum; 1646 struct avtab_node *node; 1647 u16 tclass; 1648 int rc = 0; 1649 bool sock; 1650 1651 if (!state->initialized) { 1652 switch (orig_tclass) { 1653 case SECCLASS_PROCESS: /* kernel value */ 1654 *out_sid = ssid; 1655 break; 1656 default: 1657 *out_sid = tsid; 1658 break; 1659 } 1660 goto out; 1661 } 1662 1663 context_init(&newcontext); 1664 1665 read_lock(&state->ss->policy_rwlock); 1666 1667 if (kern) { 1668 tclass = unmap_class(&state->ss->map, orig_tclass); 1669 sock = security_is_socket_class(orig_tclass); 1670 } else { 1671 tclass = orig_tclass; 1672 sock = security_is_socket_class(map_class(&state->ss->map, 1673 tclass)); 1674 } 1675 1676 policydb = &state->ss->policydb; 1677 sidtab = &state->ss->sidtab; 1678 1679 scontext = sidtab_search(sidtab, ssid); 1680 if (!scontext) { 1681 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1682 __func__, ssid); 1683 rc = -EINVAL; 1684 goto out_unlock; 1685 } 1686 tcontext = sidtab_search(sidtab, tsid); 1687 if (!tcontext) { 1688 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1689 __func__, tsid); 1690 rc = -EINVAL; 1691 goto out_unlock; 1692 } 1693 1694 if (tclass && tclass <= policydb->p_classes.nprim) 1695 cladatum = policydb->class_val_to_struct[tclass - 1]; 1696 1697 /* Set the user identity. */ 1698 switch (specified) { 1699 case AVTAB_TRANSITION: 1700 case AVTAB_CHANGE: 1701 if (cladatum && cladatum->default_user == DEFAULT_TARGET) { 1702 newcontext.user = tcontext->user; 1703 } else { 1704 /* notice this gets both DEFAULT_SOURCE and unset */ 1705 /* Use the process user identity. */ 1706 newcontext.user = scontext->user; 1707 } 1708 break; 1709 case AVTAB_MEMBER: 1710 /* Use the related object owner. */ 1711 newcontext.user = tcontext->user; 1712 break; 1713 } 1714 1715 /* Set the role to default values. */ 1716 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) { 1717 newcontext.role = scontext->role; 1718 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { 1719 newcontext.role = tcontext->role; 1720 } else { 1721 if ((tclass == policydb->process_class) || (sock == true)) 1722 newcontext.role = scontext->role; 1723 else 1724 newcontext.role = OBJECT_R_VAL; 1725 } 1726 1727 /* Set the type to default values. */ 1728 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) { 1729 newcontext.type = scontext->type; 1730 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { 1731 newcontext.type = tcontext->type; 1732 } else { 1733 if ((tclass == policydb->process_class) || (sock == true)) { 1734 /* Use the type of process. */ 1735 newcontext.type = scontext->type; 1736 } else { 1737 /* Use the type of the related object. */ 1738 newcontext.type = tcontext->type; 1739 } 1740 } 1741 1742 /* Look for a type transition/member/change rule. */ 1743 avkey.source_type = scontext->type; 1744 avkey.target_type = tcontext->type; 1745 avkey.target_class = tclass; 1746 avkey.specified = specified; 1747 avdatum = avtab_search(&policydb->te_avtab, &avkey); 1748 1749 /* If no permanent rule, also check for enabled conditional rules */ 1750 if (!avdatum) { 1751 node = avtab_search_node(&policydb->te_cond_avtab, &avkey); 1752 for (; node; node = avtab_search_node_next(node, specified)) { 1753 if (node->key.specified & AVTAB_ENABLED) { 1754 avdatum = &node->datum; 1755 break; 1756 } 1757 } 1758 } 1759 1760 if (avdatum) { 1761 /* Use the type from the type transition/member/change rule. */ 1762 newcontext.type = avdatum->u.data; 1763 } 1764 1765 /* if we have a objname this is a file trans check so check those rules */ 1766 if (objname) 1767 filename_compute_type(policydb, &newcontext, scontext->type, 1768 tcontext->type, tclass, objname); 1769 1770 /* Check for class-specific changes. */ 1771 if (specified & AVTAB_TRANSITION) { 1772 /* Look for a role transition rule. */ 1773 for (roletr = policydb->role_tr; roletr; 1774 roletr = roletr->next) { 1775 if ((roletr->role == scontext->role) && 1776 (roletr->type == tcontext->type) && 1777 (roletr->tclass == tclass)) { 1778 /* Use the role transition rule. */ 1779 newcontext.role = roletr->new_role; 1780 break; 1781 } 1782 } 1783 } 1784 1785 /* Set the MLS attributes. 1786 This is done last because it may allocate memory. */ 1787 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified, 1788 &newcontext, sock); 1789 if (rc) 1790 goto out_unlock; 1791 1792 /* Check the validity of the context. */ 1793 if (!policydb_context_isvalid(policydb, &newcontext)) { 1794 rc = compute_sid_handle_invalid_context(state, scontext, 1795 tcontext, 1796 tclass, 1797 &newcontext); 1798 if (rc) 1799 goto out_unlock; 1800 } 1801 /* Obtain the sid for the context. */ 1802 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid); 1803 out_unlock: 1804 read_unlock(&state->ss->policy_rwlock); 1805 context_destroy(&newcontext); 1806 out: 1807 return rc; 1808 } 1809 1810 /** 1811 * security_transition_sid - Compute the SID for a new subject/object. 1812 * @ssid: source security identifier 1813 * @tsid: target security identifier 1814 * @tclass: target security class 1815 * @out_sid: security identifier for new subject/object 1816 * 1817 * Compute a SID to use for labeling a new subject or object in the 1818 * class @tclass based on a SID pair (@ssid, @tsid). 1819 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1820 * if insufficient memory is available, or %0 if the new SID was 1821 * computed successfully. 1822 */ 1823 int security_transition_sid(struct selinux_state *state, 1824 u32 ssid, u32 tsid, u16 tclass, 1825 const struct qstr *qstr, u32 *out_sid) 1826 { 1827 return security_compute_sid(state, ssid, tsid, tclass, 1828 AVTAB_TRANSITION, 1829 qstr ? qstr->name : NULL, out_sid, true); 1830 } 1831 1832 int security_transition_sid_user(struct selinux_state *state, 1833 u32 ssid, u32 tsid, u16 tclass, 1834 const char *objname, u32 *out_sid) 1835 { 1836 return security_compute_sid(state, ssid, tsid, tclass, 1837 AVTAB_TRANSITION, 1838 objname, out_sid, false); 1839 } 1840 1841 /** 1842 * security_member_sid - Compute the SID for member selection. 1843 * @ssid: source security identifier 1844 * @tsid: target security identifier 1845 * @tclass: target security class 1846 * @out_sid: security identifier for selected member 1847 * 1848 * Compute a SID to use when selecting a member of a polyinstantiated 1849 * object of class @tclass based on a SID pair (@ssid, @tsid). 1850 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1851 * if insufficient memory is available, or %0 if the SID was 1852 * computed successfully. 1853 */ 1854 int security_member_sid(struct selinux_state *state, 1855 u32 ssid, 1856 u32 tsid, 1857 u16 tclass, 1858 u32 *out_sid) 1859 { 1860 return security_compute_sid(state, ssid, tsid, tclass, 1861 AVTAB_MEMBER, NULL, 1862 out_sid, false); 1863 } 1864 1865 /** 1866 * security_change_sid - Compute the SID for object relabeling. 1867 * @ssid: source security identifier 1868 * @tsid: target security identifier 1869 * @tclass: target security class 1870 * @out_sid: security identifier for selected member 1871 * 1872 * Compute a SID to use for relabeling an object of class @tclass 1873 * based on a SID pair (@ssid, @tsid). 1874 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1875 * if insufficient memory is available, or %0 if the SID was 1876 * computed successfully. 1877 */ 1878 int security_change_sid(struct selinux_state *state, 1879 u32 ssid, 1880 u32 tsid, 1881 u16 tclass, 1882 u32 *out_sid) 1883 { 1884 return security_compute_sid(state, 1885 ssid, tsid, tclass, AVTAB_CHANGE, NULL, 1886 out_sid, false); 1887 } 1888 1889 /* Clone the SID into the new SID table. */ 1890 static int clone_sid(u32 sid, 1891 struct context *context, 1892 void *arg) 1893 { 1894 struct sidtab *s = arg; 1895 1896 if (sid > SECINITSID_NUM) 1897 return sidtab_insert(s, sid, context); 1898 else 1899 return 0; 1900 } 1901 1902 static inline int convert_context_handle_invalid_context( 1903 struct selinux_state *state, 1904 struct context *context) 1905 { 1906 struct policydb *policydb = &state->ss->policydb; 1907 char *s; 1908 u32 len; 1909 1910 if (enforcing_enabled(state)) 1911 return -EINVAL; 1912 1913 if (!context_struct_to_string(policydb, context, &s, &len)) { 1914 printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s); 1915 kfree(s); 1916 } 1917 return 0; 1918 } 1919 1920 struct convert_context_args { 1921 struct selinux_state *state; 1922 struct policydb *oldp; 1923 struct policydb *newp; 1924 }; 1925 1926 /* 1927 * Convert the values in the security context 1928 * structure `c' from the values specified 1929 * in the policy `p->oldp' to the values specified 1930 * in the policy `p->newp'. Verify that the 1931 * context is valid under the new policy. 1932 */ 1933 static int convert_context(u32 key, 1934 struct context *c, 1935 void *p) 1936 { 1937 struct convert_context_args *args; 1938 struct context oldc; 1939 struct ocontext *oc; 1940 struct mls_range *range; 1941 struct role_datum *role; 1942 struct type_datum *typdatum; 1943 struct user_datum *usrdatum; 1944 char *s; 1945 u32 len; 1946 int rc = 0; 1947 1948 if (key <= SECINITSID_NUM) 1949 goto out; 1950 1951 args = p; 1952 1953 if (c->str) { 1954 struct context ctx; 1955 1956 rc = -ENOMEM; 1957 s = kstrdup(c->str, GFP_KERNEL); 1958 if (!s) 1959 goto out; 1960 1961 rc = string_to_context_struct(args->newp, NULL, s, 1962 c->len, &ctx, SECSID_NULL); 1963 kfree(s); 1964 if (!rc) { 1965 printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n", 1966 c->str); 1967 /* Replace string with mapped representation. */ 1968 kfree(c->str); 1969 memcpy(c, &ctx, sizeof(*c)); 1970 goto out; 1971 } else if (rc == -EINVAL) { 1972 /* Retain string representation for later mapping. */ 1973 rc = 0; 1974 goto out; 1975 } else { 1976 /* Other error condition, e.g. ENOMEM. */ 1977 printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n", 1978 c->str, -rc); 1979 goto out; 1980 } 1981 } 1982 1983 rc = context_cpy(&oldc, c); 1984 if (rc) 1985 goto out; 1986 1987 /* Convert the user. */ 1988 rc = -EINVAL; 1989 usrdatum = hashtab_search(args->newp->p_users.table, 1990 sym_name(args->oldp, SYM_USERS, c->user - 1)); 1991 if (!usrdatum) 1992 goto bad; 1993 c->user = usrdatum->value; 1994 1995 /* Convert the role. */ 1996 rc = -EINVAL; 1997 role = hashtab_search(args->newp->p_roles.table, 1998 sym_name(args->oldp, SYM_ROLES, c->role - 1)); 1999 if (!role) 2000 goto bad; 2001 c->role = role->value; 2002 2003 /* Convert the type. */ 2004 rc = -EINVAL; 2005 typdatum = hashtab_search(args->newp->p_types.table, 2006 sym_name(args->oldp, SYM_TYPES, c->type - 1)); 2007 if (!typdatum) 2008 goto bad; 2009 c->type = typdatum->value; 2010 2011 /* Convert the MLS fields if dealing with MLS policies */ 2012 if (args->oldp->mls_enabled && args->newp->mls_enabled) { 2013 rc = mls_convert_context(args->oldp, args->newp, c); 2014 if (rc) 2015 goto bad; 2016 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { 2017 /* 2018 * Switching between MLS and non-MLS policy: 2019 * free any storage used by the MLS fields in the 2020 * context for all existing entries in the sidtab. 2021 */ 2022 mls_context_destroy(c); 2023 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { 2024 /* 2025 * Switching between non-MLS and MLS policy: 2026 * ensure that the MLS fields of the context for all 2027 * existing entries in the sidtab are filled in with a 2028 * suitable default value, likely taken from one of the 2029 * initial SIDs. 2030 */ 2031 oc = args->newp->ocontexts[OCON_ISID]; 2032 while (oc && oc->sid[0] != SECINITSID_UNLABELED) 2033 oc = oc->next; 2034 rc = -EINVAL; 2035 if (!oc) { 2036 printk(KERN_ERR "SELinux: unable to look up" 2037 " the initial SIDs list\n"); 2038 goto bad; 2039 } 2040 range = &oc->context[0].range; 2041 rc = mls_range_set(c, range); 2042 if (rc) 2043 goto bad; 2044 } 2045 2046 /* Check the validity of the new context. */ 2047 if (!policydb_context_isvalid(args->newp, c)) { 2048 rc = convert_context_handle_invalid_context(args->state, 2049 &oldc); 2050 if (rc) 2051 goto bad; 2052 } 2053 2054 context_destroy(&oldc); 2055 2056 rc = 0; 2057 out: 2058 return rc; 2059 bad: 2060 /* Map old representation to string and save it. */ 2061 rc = context_struct_to_string(args->oldp, &oldc, &s, &len); 2062 if (rc) 2063 return rc; 2064 context_destroy(&oldc); 2065 context_destroy(c); 2066 c->str = s; 2067 c->len = len; 2068 printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n", 2069 c->str); 2070 rc = 0; 2071 goto out; 2072 } 2073 2074 static void security_load_policycaps(struct selinux_state *state) 2075 { 2076 struct policydb *p = &state->ss->policydb; 2077 unsigned int i; 2078 struct ebitmap_node *node; 2079 2080 for (i = 0; i < ARRAY_SIZE(state->policycap); i++) 2081 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i); 2082 2083 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) 2084 pr_info("SELinux: policy capability %s=%d\n", 2085 selinux_policycap_names[i], 2086 ebitmap_get_bit(&p->policycaps, i)); 2087 2088 ebitmap_for_each_positive_bit(&p->policycaps, node, i) { 2089 if (i >= ARRAY_SIZE(selinux_policycap_names)) 2090 pr_info("SELinux: unknown policy capability %u\n", 2091 i); 2092 } 2093 } 2094 2095 static int security_preserve_bools(struct selinux_state *state, 2096 struct policydb *newpolicydb); 2097 2098 /** 2099 * security_load_policy - Load a security policy configuration. 2100 * @data: binary policy data 2101 * @len: length of data in bytes 2102 * 2103 * Load a new set of security policy configuration data, 2104 * validate it and convert the SID table as necessary. 2105 * This function will flush the access vector cache after 2106 * loading the new policy. 2107 */ 2108 int security_load_policy(struct selinux_state *state, void *data, size_t len) 2109 { 2110 struct policydb *policydb; 2111 struct sidtab *sidtab; 2112 struct policydb *oldpolicydb, *newpolicydb; 2113 struct sidtab oldsidtab, newsidtab; 2114 struct selinux_mapping *oldmapping; 2115 struct selinux_map newmap; 2116 struct convert_context_args args; 2117 u32 seqno; 2118 int rc = 0; 2119 struct policy_file file = { data, len }, *fp = &file; 2120 2121 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL); 2122 if (!oldpolicydb) { 2123 rc = -ENOMEM; 2124 goto out; 2125 } 2126 newpolicydb = oldpolicydb + 1; 2127 2128 policydb = &state->ss->policydb; 2129 sidtab = &state->ss->sidtab; 2130 2131 if (!state->initialized) { 2132 rc = policydb_read(policydb, fp); 2133 if (rc) 2134 goto out; 2135 2136 policydb->len = len; 2137 rc = selinux_set_mapping(policydb, secclass_map, 2138 &state->ss->map); 2139 if (rc) { 2140 policydb_destroy(policydb); 2141 goto out; 2142 } 2143 2144 rc = policydb_load_isids(policydb, sidtab); 2145 if (rc) { 2146 policydb_destroy(policydb); 2147 goto out; 2148 } 2149 2150 security_load_policycaps(state); 2151 state->initialized = 1; 2152 seqno = ++state->ss->latest_granting; 2153 selinux_complete_init(); 2154 avc_ss_reset(state->avc, seqno); 2155 selnl_notify_policyload(seqno); 2156 selinux_status_update_policyload(state, seqno); 2157 selinux_netlbl_cache_invalidate(); 2158 selinux_xfrm_notify_policyload(); 2159 goto out; 2160 } 2161 2162 #if 0 2163 sidtab_hash_eval(sidtab, "sids"); 2164 #endif 2165 2166 rc = policydb_read(newpolicydb, fp); 2167 if (rc) 2168 goto out; 2169 2170 newpolicydb->len = len; 2171 /* If switching between different policy types, log MLS status */ 2172 if (policydb->mls_enabled && !newpolicydb->mls_enabled) 2173 printk(KERN_INFO "SELinux: Disabling MLS support...\n"); 2174 else if (!policydb->mls_enabled && newpolicydb->mls_enabled) 2175 printk(KERN_INFO "SELinux: Enabling MLS support...\n"); 2176 2177 rc = policydb_load_isids(newpolicydb, &newsidtab); 2178 if (rc) { 2179 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); 2180 policydb_destroy(newpolicydb); 2181 goto out; 2182 } 2183 2184 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap); 2185 if (rc) 2186 goto err; 2187 2188 rc = security_preserve_bools(state, newpolicydb); 2189 if (rc) { 2190 printk(KERN_ERR "SELinux: unable to preserve booleans\n"); 2191 goto err; 2192 } 2193 2194 /* Clone the SID table. */ 2195 sidtab_shutdown(sidtab); 2196 2197 rc = sidtab_map(sidtab, clone_sid, &newsidtab); 2198 if (rc) 2199 goto err; 2200 2201 /* 2202 * Convert the internal representations of contexts 2203 * in the new SID table. 2204 */ 2205 args.state = state; 2206 args.oldp = policydb; 2207 args.newp = newpolicydb; 2208 rc = sidtab_map(&newsidtab, convert_context, &args); 2209 if (rc) { 2210 printk(KERN_ERR "SELinux: unable to convert the internal" 2211 " representation of contexts in the new SID" 2212 " table\n"); 2213 goto err; 2214 } 2215 2216 /* Save the old policydb and SID table to free later. */ 2217 memcpy(oldpolicydb, policydb, sizeof(*policydb)); 2218 sidtab_set(&oldsidtab, sidtab); 2219 2220 /* Install the new policydb and SID table. */ 2221 write_lock_irq(&state->ss->policy_rwlock); 2222 memcpy(policydb, newpolicydb, sizeof(*policydb)); 2223 sidtab_set(sidtab, &newsidtab); 2224 security_load_policycaps(state); 2225 oldmapping = state->ss->map.mapping; 2226 state->ss->map.mapping = newmap.mapping; 2227 state->ss->map.size = newmap.size; 2228 seqno = ++state->ss->latest_granting; 2229 write_unlock_irq(&state->ss->policy_rwlock); 2230 2231 /* Free the old policydb and SID table. */ 2232 policydb_destroy(oldpolicydb); 2233 sidtab_destroy(&oldsidtab); 2234 kfree(oldmapping); 2235 2236 avc_ss_reset(state->avc, seqno); 2237 selnl_notify_policyload(seqno); 2238 selinux_status_update_policyload(state, seqno); 2239 selinux_netlbl_cache_invalidate(); 2240 selinux_xfrm_notify_policyload(); 2241 2242 rc = 0; 2243 goto out; 2244 2245 err: 2246 kfree(newmap.mapping); 2247 sidtab_destroy(&newsidtab); 2248 policydb_destroy(newpolicydb); 2249 2250 out: 2251 kfree(oldpolicydb); 2252 return rc; 2253 } 2254 2255 size_t security_policydb_len(struct selinux_state *state) 2256 { 2257 struct policydb *p = &state->ss->policydb; 2258 size_t len; 2259 2260 read_lock(&state->ss->policy_rwlock); 2261 len = p->len; 2262 read_unlock(&state->ss->policy_rwlock); 2263 2264 return len; 2265 } 2266 2267 /** 2268 * security_port_sid - Obtain the SID for a port. 2269 * @protocol: protocol number 2270 * @port: port number 2271 * @out_sid: security identifier 2272 */ 2273 int security_port_sid(struct selinux_state *state, 2274 u8 protocol, u16 port, u32 *out_sid) 2275 { 2276 struct policydb *policydb; 2277 struct sidtab *sidtab; 2278 struct ocontext *c; 2279 int rc = 0; 2280 2281 read_lock(&state->ss->policy_rwlock); 2282 2283 policydb = &state->ss->policydb; 2284 sidtab = &state->ss->sidtab; 2285 2286 c = policydb->ocontexts[OCON_PORT]; 2287 while (c) { 2288 if (c->u.port.protocol == protocol && 2289 c->u.port.low_port <= port && 2290 c->u.port.high_port >= port) 2291 break; 2292 c = c->next; 2293 } 2294 2295 if (c) { 2296 if (!c->sid[0]) { 2297 rc = sidtab_context_to_sid(sidtab, 2298 &c->context[0], 2299 &c->sid[0]); 2300 if (rc) 2301 goto out; 2302 } 2303 *out_sid = c->sid[0]; 2304 } else { 2305 *out_sid = SECINITSID_PORT; 2306 } 2307 2308 out: 2309 read_unlock(&state->ss->policy_rwlock); 2310 return rc; 2311 } 2312 2313 /** 2314 * security_pkey_sid - Obtain the SID for a pkey. 2315 * @subnet_prefix: Subnet Prefix 2316 * @pkey_num: pkey number 2317 * @out_sid: security identifier 2318 */ 2319 int security_ib_pkey_sid(struct selinux_state *state, 2320 u64 subnet_prefix, u16 pkey_num, u32 *out_sid) 2321 { 2322 struct policydb *policydb; 2323 struct sidtab *sidtab; 2324 struct ocontext *c; 2325 int rc = 0; 2326 2327 read_lock(&state->ss->policy_rwlock); 2328 2329 policydb = &state->ss->policydb; 2330 sidtab = &state->ss->sidtab; 2331 2332 c = policydb->ocontexts[OCON_IBPKEY]; 2333 while (c) { 2334 if (c->u.ibpkey.low_pkey <= pkey_num && 2335 c->u.ibpkey.high_pkey >= pkey_num && 2336 c->u.ibpkey.subnet_prefix == subnet_prefix) 2337 break; 2338 2339 c = c->next; 2340 } 2341 2342 if (c) { 2343 if (!c->sid[0]) { 2344 rc = sidtab_context_to_sid(sidtab, 2345 &c->context[0], 2346 &c->sid[0]); 2347 if (rc) 2348 goto out; 2349 } 2350 *out_sid = c->sid[0]; 2351 } else 2352 *out_sid = SECINITSID_UNLABELED; 2353 2354 out: 2355 read_unlock(&state->ss->policy_rwlock); 2356 return rc; 2357 } 2358 2359 /** 2360 * security_ib_endport_sid - Obtain the SID for a subnet management interface. 2361 * @dev_name: device name 2362 * @port: port number 2363 * @out_sid: security identifier 2364 */ 2365 int security_ib_endport_sid(struct selinux_state *state, 2366 const char *dev_name, u8 port_num, u32 *out_sid) 2367 { 2368 struct policydb *policydb; 2369 struct sidtab *sidtab; 2370 struct ocontext *c; 2371 int rc = 0; 2372 2373 read_lock(&state->ss->policy_rwlock); 2374 2375 policydb = &state->ss->policydb; 2376 sidtab = &state->ss->sidtab; 2377 2378 c = policydb->ocontexts[OCON_IBENDPORT]; 2379 while (c) { 2380 if (c->u.ibendport.port == port_num && 2381 !strncmp(c->u.ibendport.dev_name, 2382 dev_name, 2383 IB_DEVICE_NAME_MAX)) 2384 break; 2385 2386 c = c->next; 2387 } 2388 2389 if (c) { 2390 if (!c->sid[0]) { 2391 rc = sidtab_context_to_sid(sidtab, 2392 &c->context[0], 2393 &c->sid[0]); 2394 if (rc) 2395 goto out; 2396 } 2397 *out_sid = c->sid[0]; 2398 } else 2399 *out_sid = SECINITSID_UNLABELED; 2400 2401 out: 2402 read_unlock(&state->ss->policy_rwlock); 2403 return rc; 2404 } 2405 2406 /** 2407 * security_netif_sid - Obtain the SID for a network interface. 2408 * @name: interface name 2409 * @if_sid: interface SID 2410 */ 2411 int security_netif_sid(struct selinux_state *state, 2412 char *name, u32 *if_sid) 2413 { 2414 struct policydb *policydb; 2415 struct sidtab *sidtab; 2416 int rc = 0; 2417 struct ocontext *c; 2418 2419 read_lock(&state->ss->policy_rwlock); 2420 2421 policydb = &state->ss->policydb; 2422 sidtab = &state->ss->sidtab; 2423 2424 c = policydb->ocontexts[OCON_NETIF]; 2425 while (c) { 2426 if (strcmp(name, c->u.name) == 0) 2427 break; 2428 c = c->next; 2429 } 2430 2431 if (c) { 2432 if (!c->sid[0] || !c->sid[1]) { 2433 rc = sidtab_context_to_sid(sidtab, 2434 &c->context[0], 2435 &c->sid[0]); 2436 if (rc) 2437 goto out; 2438 rc = sidtab_context_to_sid(sidtab, 2439 &c->context[1], 2440 &c->sid[1]); 2441 if (rc) 2442 goto out; 2443 } 2444 *if_sid = c->sid[0]; 2445 } else 2446 *if_sid = SECINITSID_NETIF; 2447 2448 out: 2449 read_unlock(&state->ss->policy_rwlock); 2450 return rc; 2451 } 2452 2453 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) 2454 { 2455 int i, fail = 0; 2456 2457 for (i = 0; i < 4; i++) 2458 if (addr[i] != (input[i] & mask[i])) { 2459 fail = 1; 2460 break; 2461 } 2462 2463 return !fail; 2464 } 2465 2466 /** 2467 * security_node_sid - Obtain the SID for a node (host). 2468 * @domain: communication domain aka address family 2469 * @addrp: address 2470 * @addrlen: address length in bytes 2471 * @out_sid: security identifier 2472 */ 2473 int security_node_sid(struct selinux_state *state, 2474 u16 domain, 2475 void *addrp, 2476 u32 addrlen, 2477 u32 *out_sid) 2478 { 2479 struct policydb *policydb; 2480 struct sidtab *sidtab; 2481 int rc; 2482 struct ocontext *c; 2483 2484 read_lock(&state->ss->policy_rwlock); 2485 2486 policydb = &state->ss->policydb; 2487 sidtab = &state->ss->sidtab; 2488 2489 switch (domain) { 2490 case AF_INET: { 2491 u32 addr; 2492 2493 rc = -EINVAL; 2494 if (addrlen != sizeof(u32)) 2495 goto out; 2496 2497 addr = *((u32 *)addrp); 2498 2499 c = policydb->ocontexts[OCON_NODE]; 2500 while (c) { 2501 if (c->u.node.addr == (addr & c->u.node.mask)) 2502 break; 2503 c = c->next; 2504 } 2505 break; 2506 } 2507 2508 case AF_INET6: 2509 rc = -EINVAL; 2510 if (addrlen != sizeof(u64) * 2) 2511 goto out; 2512 c = policydb->ocontexts[OCON_NODE6]; 2513 while (c) { 2514 if (match_ipv6_addrmask(addrp, c->u.node6.addr, 2515 c->u.node6.mask)) 2516 break; 2517 c = c->next; 2518 } 2519 break; 2520 2521 default: 2522 rc = 0; 2523 *out_sid = SECINITSID_NODE; 2524 goto out; 2525 } 2526 2527 if (c) { 2528 if (!c->sid[0]) { 2529 rc = sidtab_context_to_sid(sidtab, 2530 &c->context[0], 2531 &c->sid[0]); 2532 if (rc) 2533 goto out; 2534 } 2535 *out_sid = c->sid[0]; 2536 } else { 2537 *out_sid = SECINITSID_NODE; 2538 } 2539 2540 rc = 0; 2541 out: 2542 read_unlock(&state->ss->policy_rwlock); 2543 return rc; 2544 } 2545 2546 #define SIDS_NEL 25 2547 2548 /** 2549 * security_get_user_sids - Obtain reachable SIDs for a user. 2550 * @fromsid: starting SID 2551 * @username: username 2552 * @sids: array of reachable SIDs for user 2553 * @nel: number of elements in @sids 2554 * 2555 * Generate the set of SIDs for legal security contexts 2556 * for a given user that can be reached by @fromsid. 2557 * Set *@sids to point to a dynamically allocated 2558 * array containing the set of SIDs. Set *@nel to the 2559 * number of elements in the array. 2560 */ 2561 2562 int security_get_user_sids(struct selinux_state *state, 2563 u32 fromsid, 2564 char *username, 2565 u32 **sids, 2566 u32 *nel) 2567 { 2568 struct policydb *policydb; 2569 struct sidtab *sidtab; 2570 struct context *fromcon, usercon; 2571 u32 *mysids = NULL, *mysids2, sid; 2572 u32 mynel = 0, maxnel = SIDS_NEL; 2573 struct user_datum *user; 2574 struct role_datum *role; 2575 struct ebitmap_node *rnode, *tnode; 2576 int rc = 0, i, j; 2577 2578 *sids = NULL; 2579 *nel = 0; 2580 2581 if (!state->initialized) 2582 goto out; 2583 2584 read_lock(&state->ss->policy_rwlock); 2585 2586 policydb = &state->ss->policydb; 2587 sidtab = &state->ss->sidtab; 2588 2589 context_init(&usercon); 2590 2591 rc = -EINVAL; 2592 fromcon = sidtab_search(sidtab, fromsid); 2593 if (!fromcon) 2594 goto out_unlock; 2595 2596 rc = -EINVAL; 2597 user = hashtab_search(policydb->p_users.table, username); 2598 if (!user) 2599 goto out_unlock; 2600 2601 usercon.user = user->value; 2602 2603 rc = -ENOMEM; 2604 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); 2605 if (!mysids) 2606 goto out_unlock; 2607 2608 ebitmap_for_each_positive_bit(&user->roles, rnode, i) { 2609 role = policydb->role_val_to_struct[i]; 2610 usercon.role = i + 1; 2611 ebitmap_for_each_positive_bit(&role->types, tnode, j) { 2612 usercon.type = j + 1; 2613 2614 if (mls_setup_user_range(policydb, fromcon, user, 2615 &usercon)) 2616 continue; 2617 2618 rc = sidtab_context_to_sid(sidtab, &usercon, &sid); 2619 if (rc) 2620 goto out_unlock; 2621 if (mynel < maxnel) { 2622 mysids[mynel++] = sid; 2623 } else { 2624 rc = -ENOMEM; 2625 maxnel += SIDS_NEL; 2626 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); 2627 if (!mysids2) 2628 goto out_unlock; 2629 memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); 2630 kfree(mysids); 2631 mysids = mysids2; 2632 mysids[mynel++] = sid; 2633 } 2634 } 2635 } 2636 rc = 0; 2637 out_unlock: 2638 read_unlock(&state->ss->policy_rwlock); 2639 if (rc || !mynel) { 2640 kfree(mysids); 2641 goto out; 2642 } 2643 2644 rc = -ENOMEM; 2645 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); 2646 if (!mysids2) { 2647 kfree(mysids); 2648 goto out; 2649 } 2650 for (i = 0, j = 0; i < mynel; i++) { 2651 struct av_decision dummy_avd; 2652 rc = avc_has_perm_noaudit(state, 2653 fromsid, mysids[i], 2654 SECCLASS_PROCESS, /* kernel value */ 2655 PROCESS__TRANSITION, AVC_STRICT, 2656 &dummy_avd); 2657 if (!rc) 2658 mysids2[j++] = mysids[i]; 2659 cond_resched(); 2660 } 2661 rc = 0; 2662 kfree(mysids); 2663 *sids = mysids2; 2664 *nel = j; 2665 out: 2666 return rc; 2667 } 2668 2669 /** 2670 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem 2671 * @fstype: filesystem type 2672 * @path: path from root of mount 2673 * @sclass: file security class 2674 * @sid: SID for path 2675 * 2676 * Obtain a SID to use for a file in a filesystem that 2677 * cannot support xattr or use a fixed labeling behavior like 2678 * transition SIDs or task SIDs. 2679 * 2680 * The caller must acquire the policy_rwlock before calling this function. 2681 */ 2682 static inline int __security_genfs_sid(struct selinux_state *state, 2683 const char *fstype, 2684 char *path, 2685 u16 orig_sclass, 2686 u32 *sid) 2687 { 2688 struct policydb *policydb = &state->ss->policydb; 2689 struct sidtab *sidtab = &state->ss->sidtab; 2690 int len; 2691 u16 sclass; 2692 struct genfs *genfs; 2693 struct ocontext *c; 2694 int rc, cmp = 0; 2695 2696 while (path[0] == '/' && path[1] == '/') 2697 path++; 2698 2699 sclass = unmap_class(&state->ss->map, orig_sclass); 2700 *sid = SECINITSID_UNLABELED; 2701 2702 for (genfs = policydb->genfs; genfs; genfs = genfs->next) { 2703 cmp = strcmp(fstype, genfs->fstype); 2704 if (cmp <= 0) 2705 break; 2706 } 2707 2708 rc = -ENOENT; 2709 if (!genfs || cmp) 2710 goto out; 2711 2712 for (c = genfs->head; c; c = c->next) { 2713 len = strlen(c->u.name); 2714 if ((!c->v.sclass || sclass == c->v.sclass) && 2715 (strncmp(c->u.name, path, len) == 0)) 2716 break; 2717 } 2718 2719 rc = -ENOENT; 2720 if (!c) 2721 goto out; 2722 2723 if (!c->sid[0]) { 2724 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]); 2725 if (rc) 2726 goto out; 2727 } 2728 2729 *sid = c->sid[0]; 2730 rc = 0; 2731 out: 2732 return rc; 2733 } 2734 2735 /** 2736 * security_genfs_sid - Obtain a SID for a file in a filesystem 2737 * @fstype: filesystem type 2738 * @path: path from root of mount 2739 * @sclass: file security class 2740 * @sid: SID for path 2741 * 2742 * Acquire policy_rwlock before calling __security_genfs_sid() and release 2743 * it afterward. 2744 */ 2745 int security_genfs_sid(struct selinux_state *state, 2746 const char *fstype, 2747 char *path, 2748 u16 orig_sclass, 2749 u32 *sid) 2750 { 2751 int retval; 2752 2753 read_lock(&state->ss->policy_rwlock); 2754 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid); 2755 read_unlock(&state->ss->policy_rwlock); 2756 return retval; 2757 } 2758 2759 /** 2760 * security_fs_use - Determine how to handle labeling for a filesystem. 2761 * @sb: superblock in question 2762 */ 2763 int security_fs_use(struct selinux_state *state, struct super_block *sb) 2764 { 2765 struct policydb *policydb; 2766 struct sidtab *sidtab; 2767 int rc = 0; 2768 struct ocontext *c; 2769 struct superblock_security_struct *sbsec = sb->s_security; 2770 const char *fstype = sb->s_type->name; 2771 2772 read_lock(&state->ss->policy_rwlock); 2773 2774 policydb = &state->ss->policydb; 2775 sidtab = &state->ss->sidtab; 2776 2777 c = policydb->ocontexts[OCON_FSUSE]; 2778 while (c) { 2779 if (strcmp(fstype, c->u.name) == 0) 2780 break; 2781 c = c->next; 2782 } 2783 2784 if (c) { 2785 sbsec->behavior = c->v.behavior; 2786 if (!c->sid[0]) { 2787 rc = sidtab_context_to_sid(sidtab, &c->context[0], 2788 &c->sid[0]); 2789 if (rc) 2790 goto out; 2791 } 2792 sbsec->sid = c->sid[0]; 2793 } else { 2794 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR, 2795 &sbsec->sid); 2796 if (rc) { 2797 sbsec->behavior = SECURITY_FS_USE_NONE; 2798 rc = 0; 2799 } else { 2800 sbsec->behavior = SECURITY_FS_USE_GENFS; 2801 } 2802 } 2803 2804 out: 2805 read_unlock(&state->ss->policy_rwlock); 2806 return rc; 2807 } 2808 2809 int security_get_bools(struct selinux_state *state, 2810 int *len, char ***names, int **values) 2811 { 2812 struct policydb *policydb; 2813 int i, rc; 2814 2815 if (!state->initialized) { 2816 *len = 0; 2817 *names = NULL; 2818 *values = NULL; 2819 return 0; 2820 } 2821 2822 read_lock(&state->ss->policy_rwlock); 2823 2824 policydb = &state->ss->policydb; 2825 2826 *names = NULL; 2827 *values = NULL; 2828 2829 rc = 0; 2830 *len = policydb->p_bools.nprim; 2831 if (!*len) 2832 goto out; 2833 2834 rc = -ENOMEM; 2835 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); 2836 if (!*names) 2837 goto err; 2838 2839 rc = -ENOMEM; 2840 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); 2841 if (!*values) 2842 goto err; 2843 2844 for (i = 0; i < *len; i++) { 2845 (*values)[i] = policydb->bool_val_to_struct[i]->state; 2846 2847 rc = -ENOMEM; 2848 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i), 2849 GFP_ATOMIC); 2850 if (!(*names)[i]) 2851 goto err; 2852 } 2853 rc = 0; 2854 out: 2855 read_unlock(&state->ss->policy_rwlock); 2856 return rc; 2857 err: 2858 if (*names) { 2859 for (i = 0; i < *len; i++) 2860 kfree((*names)[i]); 2861 } 2862 kfree(*values); 2863 goto out; 2864 } 2865 2866 2867 int security_set_bools(struct selinux_state *state, int len, int *values) 2868 { 2869 struct policydb *policydb; 2870 int i, rc; 2871 int lenp, seqno = 0; 2872 struct cond_node *cur; 2873 2874 write_lock_irq(&state->ss->policy_rwlock); 2875 2876 policydb = &state->ss->policydb; 2877 2878 rc = -EFAULT; 2879 lenp = policydb->p_bools.nprim; 2880 if (len != lenp) 2881 goto out; 2882 2883 for (i = 0; i < len; i++) { 2884 if (!!values[i] != policydb->bool_val_to_struct[i]->state) { 2885 audit_log(audit_context(), GFP_ATOMIC, 2886 AUDIT_MAC_CONFIG_CHANGE, 2887 "bool=%s val=%d old_val=%d auid=%u ses=%u", 2888 sym_name(policydb, SYM_BOOLS, i), 2889 !!values[i], 2890 policydb->bool_val_to_struct[i]->state, 2891 from_kuid(&init_user_ns, audit_get_loginuid(current)), 2892 audit_get_sessionid(current)); 2893 } 2894 if (values[i]) 2895 policydb->bool_val_to_struct[i]->state = 1; 2896 else 2897 policydb->bool_val_to_struct[i]->state = 0; 2898 } 2899 2900 for (cur = policydb->cond_list; cur; cur = cur->next) { 2901 rc = evaluate_cond_node(policydb, cur); 2902 if (rc) 2903 goto out; 2904 } 2905 2906 seqno = ++state->ss->latest_granting; 2907 rc = 0; 2908 out: 2909 write_unlock_irq(&state->ss->policy_rwlock); 2910 if (!rc) { 2911 avc_ss_reset(state->avc, seqno); 2912 selnl_notify_policyload(seqno); 2913 selinux_status_update_policyload(state, seqno); 2914 selinux_xfrm_notify_policyload(); 2915 } 2916 return rc; 2917 } 2918 2919 int security_get_bool_value(struct selinux_state *state, 2920 int index) 2921 { 2922 struct policydb *policydb; 2923 int rc; 2924 int len; 2925 2926 read_lock(&state->ss->policy_rwlock); 2927 2928 policydb = &state->ss->policydb; 2929 2930 rc = -EFAULT; 2931 len = policydb->p_bools.nprim; 2932 if (index >= len) 2933 goto out; 2934 2935 rc = policydb->bool_val_to_struct[index]->state; 2936 out: 2937 read_unlock(&state->ss->policy_rwlock); 2938 return rc; 2939 } 2940 2941 static int security_preserve_bools(struct selinux_state *state, 2942 struct policydb *policydb) 2943 { 2944 int rc, nbools = 0, *bvalues = NULL, i; 2945 char **bnames = NULL; 2946 struct cond_bool_datum *booldatum; 2947 struct cond_node *cur; 2948 2949 rc = security_get_bools(state, &nbools, &bnames, &bvalues); 2950 if (rc) 2951 goto out; 2952 for (i = 0; i < nbools; i++) { 2953 booldatum = hashtab_search(policydb->p_bools.table, bnames[i]); 2954 if (booldatum) 2955 booldatum->state = bvalues[i]; 2956 } 2957 for (cur = policydb->cond_list; cur; cur = cur->next) { 2958 rc = evaluate_cond_node(policydb, cur); 2959 if (rc) 2960 goto out; 2961 } 2962 2963 out: 2964 if (bnames) { 2965 for (i = 0; i < nbools; i++) 2966 kfree(bnames[i]); 2967 } 2968 kfree(bnames); 2969 kfree(bvalues); 2970 return rc; 2971 } 2972 2973 /* 2974 * security_sid_mls_copy() - computes a new sid based on the given 2975 * sid and the mls portion of mls_sid. 2976 */ 2977 int security_sid_mls_copy(struct selinux_state *state, 2978 u32 sid, u32 mls_sid, u32 *new_sid) 2979 { 2980 struct policydb *policydb = &state->ss->policydb; 2981 struct sidtab *sidtab = &state->ss->sidtab; 2982 struct context *context1; 2983 struct context *context2; 2984 struct context newcon; 2985 char *s; 2986 u32 len; 2987 int rc; 2988 2989 rc = 0; 2990 if (!state->initialized || !policydb->mls_enabled) { 2991 *new_sid = sid; 2992 goto out; 2993 } 2994 2995 context_init(&newcon); 2996 2997 read_lock(&state->ss->policy_rwlock); 2998 2999 rc = -EINVAL; 3000 context1 = sidtab_search(sidtab, sid); 3001 if (!context1) { 3002 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 3003 __func__, sid); 3004 goto out_unlock; 3005 } 3006 3007 rc = -EINVAL; 3008 context2 = sidtab_search(sidtab, mls_sid); 3009 if (!context2) { 3010 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 3011 __func__, mls_sid); 3012 goto out_unlock; 3013 } 3014 3015 newcon.user = context1->user; 3016 newcon.role = context1->role; 3017 newcon.type = context1->type; 3018 rc = mls_context_cpy(&newcon, context2); 3019 if (rc) 3020 goto out_unlock; 3021 3022 /* Check the validity of the new context. */ 3023 if (!policydb_context_isvalid(policydb, &newcon)) { 3024 rc = convert_context_handle_invalid_context(state, &newcon); 3025 if (rc) { 3026 if (!context_struct_to_string(policydb, &newcon, &s, 3027 &len)) { 3028 audit_log(audit_context(), 3029 GFP_ATOMIC, AUDIT_SELINUX_ERR, 3030 "op=security_sid_mls_copy " 3031 "invalid_context=%s", s); 3032 kfree(s); 3033 } 3034 goto out_unlock; 3035 } 3036 } 3037 3038 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid); 3039 out_unlock: 3040 read_unlock(&state->ss->policy_rwlock); 3041 context_destroy(&newcon); 3042 out: 3043 return rc; 3044 } 3045 3046 /** 3047 * security_net_peersid_resolve - Compare and resolve two network peer SIDs 3048 * @nlbl_sid: NetLabel SID 3049 * @nlbl_type: NetLabel labeling protocol type 3050 * @xfrm_sid: XFRM SID 3051 * 3052 * Description: 3053 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be 3054 * resolved into a single SID it is returned via @peer_sid and the function 3055 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function 3056 * returns a negative value. A table summarizing the behavior is below: 3057 * 3058 * | function return | @sid 3059 * ------------------------------+-----------------+----------------- 3060 * no peer labels | 0 | SECSID_NULL 3061 * single peer label | 0 | <peer_label> 3062 * multiple, consistent labels | 0 | <peer_label> 3063 * multiple, inconsistent labels | -<errno> | SECSID_NULL 3064 * 3065 */ 3066 int security_net_peersid_resolve(struct selinux_state *state, 3067 u32 nlbl_sid, u32 nlbl_type, 3068 u32 xfrm_sid, 3069 u32 *peer_sid) 3070 { 3071 struct policydb *policydb = &state->ss->policydb; 3072 struct sidtab *sidtab = &state->ss->sidtab; 3073 int rc; 3074 struct context *nlbl_ctx; 3075 struct context *xfrm_ctx; 3076 3077 *peer_sid = SECSID_NULL; 3078 3079 /* handle the common (which also happens to be the set of easy) cases 3080 * right away, these two if statements catch everything involving a 3081 * single or absent peer SID/label */ 3082 if (xfrm_sid == SECSID_NULL) { 3083 *peer_sid = nlbl_sid; 3084 return 0; 3085 } 3086 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label 3087 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label 3088 * is present */ 3089 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { 3090 *peer_sid = xfrm_sid; 3091 return 0; 3092 } 3093 3094 /* 3095 * We don't need to check initialized here since the only way both 3096 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the 3097 * security server was initialized and state->initialized was true. 3098 */ 3099 if (!policydb->mls_enabled) 3100 return 0; 3101 3102 read_lock(&state->ss->policy_rwlock); 3103 3104 rc = -EINVAL; 3105 nlbl_ctx = sidtab_search(sidtab, nlbl_sid); 3106 if (!nlbl_ctx) { 3107 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 3108 __func__, nlbl_sid); 3109 goto out; 3110 } 3111 rc = -EINVAL; 3112 xfrm_ctx = sidtab_search(sidtab, xfrm_sid); 3113 if (!xfrm_ctx) { 3114 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 3115 __func__, xfrm_sid); 3116 goto out; 3117 } 3118 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); 3119 if (rc) 3120 goto out; 3121 3122 /* at present NetLabel SIDs/labels really only carry MLS 3123 * information so if the MLS portion of the NetLabel SID 3124 * matches the MLS portion of the labeled XFRM SID/label 3125 * then pass along the XFRM SID as it is the most 3126 * expressive */ 3127 *peer_sid = xfrm_sid; 3128 out: 3129 read_unlock(&state->ss->policy_rwlock); 3130 return rc; 3131 } 3132 3133 static int get_classes_callback(void *k, void *d, void *args) 3134 { 3135 struct class_datum *datum = d; 3136 char *name = k, **classes = args; 3137 int value = datum->value - 1; 3138 3139 classes[value] = kstrdup(name, GFP_ATOMIC); 3140 if (!classes[value]) 3141 return -ENOMEM; 3142 3143 return 0; 3144 } 3145 3146 int security_get_classes(struct selinux_state *state, 3147 char ***classes, int *nclasses) 3148 { 3149 struct policydb *policydb = &state->ss->policydb; 3150 int rc; 3151 3152 if (!state->initialized) { 3153 *nclasses = 0; 3154 *classes = NULL; 3155 return 0; 3156 } 3157 3158 read_lock(&state->ss->policy_rwlock); 3159 3160 rc = -ENOMEM; 3161 *nclasses = policydb->p_classes.nprim; 3162 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); 3163 if (!*classes) 3164 goto out; 3165 3166 rc = hashtab_map(policydb->p_classes.table, get_classes_callback, 3167 *classes); 3168 if (rc) { 3169 int i; 3170 for (i = 0; i < *nclasses; i++) 3171 kfree((*classes)[i]); 3172 kfree(*classes); 3173 } 3174 3175 out: 3176 read_unlock(&state->ss->policy_rwlock); 3177 return rc; 3178 } 3179 3180 static int get_permissions_callback(void *k, void *d, void *args) 3181 { 3182 struct perm_datum *datum = d; 3183 char *name = k, **perms = args; 3184 int value = datum->value - 1; 3185 3186 perms[value] = kstrdup(name, GFP_ATOMIC); 3187 if (!perms[value]) 3188 return -ENOMEM; 3189 3190 return 0; 3191 } 3192 3193 int security_get_permissions(struct selinux_state *state, 3194 char *class, char ***perms, int *nperms) 3195 { 3196 struct policydb *policydb = &state->ss->policydb; 3197 int rc, i; 3198 struct class_datum *match; 3199 3200 read_lock(&state->ss->policy_rwlock); 3201 3202 rc = -EINVAL; 3203 match = hashtab_search(policydb->p_classes.table, class); 3204 if (!match) { 3205 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n", 3206 __func__, class); 3207 goto out; 3208 } 3209 3210 rc = -ENOMEM; 3211 *nperms = match->permissions.nprim; 3212 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); 3213 if (!*perms) 3214 goto out; 3215 3216 if (match->comdatum) { 3217 rc = hashtab_map(match->comdatum->permissions.table, 3218 get_permissions_callback, *perms); 3219 if (rc) 3220 goto err; 3221 } 3222 3223 rc = hashtab_map(match->permissions.table, get_permissions_callback, 3224 *perms); 3225 if (rc) 3226 goto err; 3227 3228 out: 3229 read_unlock(&state->ss->policy_rwlock); 3230 return rc; 3231 3232 err: 3233 read_unlock(&state->ss->policy_rwlock); 3234 for (i = 0; i < *nperms; i++) 3235 kfree((*perms)[i]); 3236 kfree(*perms); 3237 return rc; 3238 } 3239 3240 int security_get_reject_unknown(struct selinux_state *state) 3241 { 3242 return state->ss->policydb.reject_unknown; 3243 } 3244 3245 int security_get_allow_unknown(struct selinux_state *state) 3246 { 3247 return state->ss->policydb.allow_unknown; 3248 } 3249 3250 /** 3251 * security_policycap_supported - Check for a specific policy capability 3252 * @req_cap: capability 3253 * 3254 * Description: 3255 * This function queries the currently loaded policy to see if it supports the 3256 * capability specified by @req_cap. Returns true (1) if the capability is 3257 * supported, false (0) if it isn't supported. 3258 * 3259 */ 3260 int security_policycap_supported(struct selinux_state *state, 3261 unsigned int req_cap) 3262 { 3263 struct policydb *policydb = &state->ss->policydb; 3264 int rc; 3265 3266 read_lock(&state->ss->policy_rwlock); 3267 rc = ebitmap_get_bit(&policydb->policycaps, req_cap); 3268 read_unlock(&state->ss->policy_rwlock); 3269 3270 return rc; 3271 } 3272 3273 struct selinux_audit_rule { 3274 u32 au_seqno; 3275 struct context au_ctxt; 3276 }; 3277 3278 void selinux_audit_rule_free(void *vrule) 3279 { 3280 struct selinux_audit_rule *rule = vrule; 3281 3282 if (rule) { 3283 context_destroy(&rule->au_ctxt); 3284 kfree(rule); 3285 } 3286 } 3287 3288 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 3289 { 3290 struct selinux_state *state = &selinux_state; 3291 struct policydb *policydb = &state->ss->policydb; 3292 struct selinux_audit_rule *tmprule; 3293 struct role_datum *roledatum; 3294 struct type_datum *typedatum; 3295 struct user_datum *userdatum; 3296 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; 3297 int rc = 0; 3298 3299 *rule = NULL; 3300 3301 if (!state->initialized) 3302 return -EOPNOTSUPP; 3303 3304 switch (field) { 3305 case AUDIT_SUBJ_USER: 3306 case AUDIT_SUBJ_ROLE: 3307 case AUDIT_SUBJ_TYPE: 3308 case AUDIT_OBJ_USER: 3309 case AUDIT_OBJ_ROLE: 3310 case AUDIT_OBJ_TYPE: 3311 /* only 'equals' and 'not equals' fit user, role, and type */ 3312 if (op != Audit_equal && op != Audit_not_equal) 3313 return -EINVAL; 3314 break; 3315 case AUDIT_SUBJ_SEN: 3316 case AUDIT_SUBJ_CLR: 3317 case AUDIT_OBJ_LEV_LOW: 3318 case AUDIT_OBJ_LEV_HIGH: 3319 /* we do not allow a range, indicated by the presence of '-' */ 3320 if (strchr(rulestr, '-')) 3321 return -EINVAL; 3322 break; 3323 default: 3324 /* only the above fields are valid */ 3325 return -EINVAL; 3326 } 3327 3328 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); 3329 if (!tmprule) 3330 return -ENOMEM; 3331 3332 context_init(&tmprule->au_ctxt); 3333 3334 read_lock(&state->ss->policy_rwlock); 3335 3336 tmprule->au_seqno = state->ss->latest_granting; 3337 3338 switch (field) { 3339 case AUDIT_SUBJ_USER: 3340 case AUDIT_OBJ_USER: 3341 rc = -EINVAL; 3342 userdatum = hashtab_search(policydb->p_users.table, rulestr); 3343 if (!userdatum) 3344 goto out; 3345 tmprule->au_ctxt.user = userdatum->value; 3346 break; 3347 case AUDIT_SUBJ_ROLE: 3348 case AUDIT_OBJ_ROLE: 3349 rc = -EINVAL; 3350 roledatum = hashtab_search(policydb->p_roles.table, rulestr); 3351 if (!roledatum) 3352 goto out; 3353 tmprule->au_ctxt.role = roledatum->value; 3354 break; 3355 case AUDIT_SUBJ_TYPE: 3356 case AUDIT_OBJ_TYPE: 3357 rc = -EINVAL; 3358 typedatum = hashtab_search(policydb->p_types.table, rulestr); 3359 if (!typedatum) 3360 goto out; 3361 tmprule->au_ctxt.type = typedatum->value; 3362 break; 3363 case AUDIT_SUBJ_SEN: 3364 case AUDIT_SUBJ_CLR: 3365 case AUDIT_OBJ_LEV_LOW: 3366 case AUDIT_OBJ_LEV_HIGH: 3367 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt, 3368 GFP_ATOMIC); 3369 if (rc) 3370 goto out; 3371 break; 3372 } 3373 rc = 0; 3374 out: 3375 read_unlock(&state->ss->policy_rwlock); 3376 3377 if (rc) { 3378 selinux_audit_rule_free(tmprule); 3379 tmprule = NULL; 3380 } 3381 3382 *rule = tmprule; 3383 3384 return rc; 3385 } 3386 3387 /* Check to see if the rule contains any selinux fields */ 3388 int selinux_audit_rule_known(struct audit_krule *rule) 3389 { 3390 int i; 3391 3392 for (i = 0; i < rule->field_count; i++) { 3393 struct audit_field *f = &rule->fields[i]; 3394 switch (f->type) { 3395 case AUDIT_SUBJ_USER: 3396 case AUDIT_SUBJ_ROLE: 3397 case AUDIT_SUBJ_TYPE: 3398 case AUDIT_SUBJ_SEN: 3399 case AUDIT_SUBJ_CLR: 3400 case AUDIT_OBJ_USER: 3401 case AUDIT_OBJ_ROLE: 3402 case AUDIT_OBJ_TYPE: 3403 case AUDIT_OBJ_LEV_LOW: 3404 case AUDIT_OBJ_LEV_HIGH: 3405 return 1; 3406 } 3407 } 3408 3409 return 0; 3410 } 3411 3412 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, 3413 struct audit_context *actx) 3414 { 3415 struct selinux_state *state = &selinux_state; 3416 struct context *ctxt; 3417 struct mls_level *level; 3418 struct selinux_audit_rule *rule = vrule; 3419 int match = 0; 3420 3421 if (unlikely(!rule)) { 3422 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n"); 3423 return -ENOENT; 3424 } 3425 3426 read_lock(&state->ss->policy_rwlock); 3427 3428 if (rule->au_seqno < state->ss->latest_granting) { 3429 match = -ESTALE; 3430 goto out; 3431 } 3432 3433 ctxt = sidtab_search(&state->ss->sidtab, sid); 3434 if (unlikely(!ctxt)) { 3435 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", 3436 sid); 3437 match = -ENOENT; 3438 goto out; 3439 } 3440 3441 /* a field/op pair that is not caught here will simply fall through 3442 without a match */ 3443 switch (field) { 3444 case AUDIT_SUBJ_USER: 3445 case AUDIT_OBJ_USER: 3446 switch (op) { 3447 case Audit_equal: 3448 match = (ctxt->user == rule->au_ctxt.user); 3449 break; 3450 case Audit_not_equal: 3451 match = (ctxt->user != rule->au_ctxt.user); 3452 break; 3453 } 3454 break; 3455 case AUDIT_SUBJ_ROLE: 3456 case AUDIT_OBJ_ROLE: 3457 switch (op) { 3458 case Audit_equal: 3459 match = (ctxt->role == rule->au_ctxt.role); 3460 break; 3461 case Audit_not_equal: 3462 match = (ctxt->role != rule->au_ctxt.role); 3463 break; 3464 } 3465 break; 3466 case AUDIT_SUBJ_TYPE: 3467 case AUDIT_OBJ_TYPE: 3468 switch (op) { 3469 case Audit_equal: 3470 match = (ctxt->type == rule->au_ctxt.type); 3471 break; 3472 case Audit_not_equal: 3473 match = (ctxt->type != rule->au_ctxt.type); 3474 break; 3475 } 3476 break; 3477 case AUDIT_SUBJ_SEN: 3478 case AUDIT_SUBJ_CLR: 3479 case AUDIT_OBJ_LEV_LOW: 3480 case AUDIT_OBJ_LEV_HIGH: 3481 level = ((field == AUDIT_SUBJ_SEN || 3482 field == AUDIT_OBJ_LEV_LOW) ? 3483 &ctxt->range.level[0] : &ctxt->range.level[1]); 3484 switch (op) { 3485 case Audit_equal: 3486 match = mls_level_eq(&rule->au_ctxt.range.level[0], 3487 level); 3488 break; 3489 case Audit_not_equal: 3490 match = !mls_level_eq(&rule->au_ctxt.range.level[0], 3491 level); 3492 break; 3493 case Audit_lt: 3494 match = (mls_level_dom(&rule->au_ctxt.range.level[0], 3495 level) && 3496 !mls_level_eq(&rule->au_ctxt.range.level[0], 3497 level)); 3498 break; 3499 case Audit_le: 3500 match = mls_level_dom(&rule->au_ctxt.range.level[0], 3501 level); 3502 break; 3503 case Audit_gt: 3504 match = (mls_level_dom(level, 3505 &rule->au_ctxt.range.level[0]) && 3506 !mls_level_eq(level, 3507 &rule->au_ctxt.range.level[0])); 3508 break; 3509 case Audit_ge: 3510 match = mls_level_dom(level, 3511 &rule->au_ctxt.range.level[0]); 3512 break; 3513 } 3514 } 3515 3516 out: 3517 read_unlock(&state->ss->policy_rwlock); 3518 return match; 3519 } 3520 3521 static int (*aurule_callback)(void) = audit_update_lsm_rules; 3522 3523 static int aurule_avc_callback(u32 event) 3524 { 3525 int err = 0; 3526 3527 if (event == AVC_CALLBACK_RESET && aurule_callback) 3528 err = aurule_callback(); 3529 return err; 3530 } 3531 3532 static int __init aurule_init(void) 3533 { 3534 int err; 3535 3536 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET); 3537 if (err) 3538 panic("avc_add_callback() failed, error %d\n", err); 3539 3540 return err; 3541 } 3542 __initcall(aurule_init); 3543 3544 #ifdef CONFIG_NETLABEL 3545 /** 3546 * security_netlbl_cache_add - Add an entry to the NetLabel cache 3547 * @secattr: the NetLabel packet security attributes 3548 * @sid: the SELinux SID 3549 * 3550 * Description: 3551 * Attempt to cache the context in @ctx, which was derived from the packet in 3552 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has 3553 * already been initialized. 3554 * 3555 */ 3556 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, 3557 u32 sid) 3558 { 3559 u32 *sid_cache; 3560 3561 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); 3562 if (sid_cache == NULL) 3563 return; 3564 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); 3565 if (secattr->cache == NULL) { 3566 kfree(sid_cache); 3567 return; 3568 } 3569 3570 *sid_cache = sid; 3571 secattr->cache->free = kfree; 3572 secattr->cache->data = sid_cache; 3573 secattr->flags |= NETLBL_SECATTR_CACHE; 3574 } 3575 3576 /** 3577 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID 3578 * @secattr: the NetLabel packet security attributes 3579 * @sid: the SELinux SID 3580 * 3581 * Description: 3582 * Convert the given NetLabel security attributes in @secattr into a 3583 * SELinux SID. If the @secattr field does not contain a full SELinux 3584 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the 3585 * 'cache' field of @secattr is set and the CACHE flag is set; this is to 3586 * allow the @secattr to be used by NetLabel to cache the secattr to SID 3587 * conversion for future lookups. Returns zero on success, negative values on 3588 * failure. 3589 * 3590 */ 3591 int security_netlbl_secattr_to_sid(struct selinux_state *state, 3592 struct netlbl_lsm_secattr *secattr, 3593 u32 *sid) 3594 { 3595 struct policydb *policydb = &state->ss->policydb; 3596 struct sidtab *sidtab = &state->ss->sidtab; 3597 int rc; 3598 struct context *ctx; 3599 struct context ctx_new; 3600 3601 if (!state->initialized) { 3602 *sid = SECSID_NULL; 3603 return 0; 3604 } 3605 3606 read_lock(&state->ss->policy_rwlock); 3607 3608 if (secattr->flags & NETLBL_SECATTR_CACHE) 3609 *sid = *(u32 *)secattr->cache->data; 3610 else if (secattr->flags & NETLBL_SECATTR_SECID) 3611 *sid = secattr->attr.secid; 3612 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { 3613 rc = -EIDRM; 3614 ctx = sidtab_search(sidtab, SECINITSID_NETMSG); 3615 if (ctx == NULL) 3616 goto out; 3617 3618 context_init(&ctx_new); 3619 ctx_new.user = ctx->user; 3620 ctx_new.role = ctx->role; 3621 ctx_new.type = ctx->type; 3622 mls_import_netlbl_lvl(policydb, &ctx_new, secattr); 3623 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { 3624 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr); 3625 if (rc) 3626 goto out; 3627 } 3628 rc = -EIDRM; 3629 if (!mls_context_isvalid(policydb, &ctx_new)) 3630 goto out_free; 3631 3632 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid); 3633 if (rc) 3634 goto out_free; 3635 3636 security_netlbl_cache_add(secattr, *sid); 3637 3638 ebitmap_destroy(&ctx_new.range.level[0].cat); 3639 } else 3640 *sid = SECSID_NULL; 3641 3642 read_unlock(&state->ss->policy_rwlock); 3643 return 0; 3644 out_free: 3645 ebitmap_destroy(&ctx_new.range.level[0].cat); 3646 out: 3647 read_unlock(&state->ss->policy_rwlock); 3648 return rc; 3649 } 3650 3651 /** 3652 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr 3653 * @sid: the SELinux SID 3654 * @secattr: the NetLabel packet security attributes 3655 * 3656 * Description: 3657 * Convert the given SELinux SID in @sid into a NetLabel security attribute. 3658 * Returns zero on success, negative values on failure. 3659 * 3660 */ 3661 int security_netlbl_sid_to_secattr(struct selinux_state *state, 3662 u32 sid, struct netlbl_lsm_secattr *secattr) 3663 { 3664 struct policydb *policydb = &state->ss->policydb; 3665 int rc; 3666 struct context *ctx; 3667 3668 if (!state->initialized) 3669 return 0; 3670 3671 read_lock(&state->ss->policy_rwlock); 3672 3673 rc = -ENOENT; 3674 ctx = sidtab_search(&state->ss->sidtab, sid); 3675 if (ctx == NULL) 3676 goto out; 3677 3678 rc = -ENOMEM; 3679 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1), 3680 GFP_ATOMIC); 3681 if (secattr->domain == NULL) 3682 goto out; 3683 3684 secattr->attr.secid = sid; 3685 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; 3686 mls_export_netlbl_lvl(policydb, ctx, secattr); 3687 rc = mls_export_netlbl_cat(policydb, ctx, secattr); 3688 out: 3689 read_unlock(&state->ss->policy_rwlock); 3690 return rc; 3691 } 3692 #endif /* CONFIG_NETLABEL */ 3693 3694 /** 3695 * security_read_policy - read the policy. 3696 * @data: binary policy data 3697 * @len: length of data in bytes 3698 * 3699 */ 3700 int security_read_policy(struct selinux_state *state, 3701 void **data, size_t *len) 3702 { 3703 struct policydb *policydb = &state->ss->policydb; 3704 int rc; 3705 struct policy_file fp; 3706 3707 if (!state->initialized) 3708 return -EINVAL; 3709 3710 *len = security_policydb_len(state); 3711 3712 *data = vmalloc_user(*len); 3713 if (!*data) 3714 return -ENOMEM; 3715 3716 fp.data = *data; 3717 fp.len = *len; 3718 3719 read_lock(&state->ss->policy_rwlock); 3720 rc = policydb_write(policydb, &fp); 3721 read_unlock(&state->ss->policy_rwlock); 3722 3723 if (rc) 3724 return rc; 3725 3726 *len = (unsigned long)fp.data - (unsigned long)*data; 3727 return 0; 3728 3729 } 3730