1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Implementation of the security services. 4 * 5 * Authors : Stephen Smalley, <sds@tycho.nsa.gov> 6 * James Morris <jmorris@redhat.com> 7 * 8 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> 9 * 10 * Support for enhanced MLS infrastructure. 11 * Support for context based audit filters. 12 * 13 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> 14 * 15 * Added conditional policy language extensions 16 * 17 * Updated: Hewlett-Packard <paul@paul-moore.com> 18 * 19 * Added support for NetLabel 20 * Added support for the policy capability bitmap 21 * 22 * Updated: Chad Sellers <csellers@tresys.com> 23 * 24 * Added validation of kernel classes and permissions 25 * 26 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com> 27 * 28 * Added support for bounds domain and audit messaged on masked permissions 29 * 30 * Updated: Guido Trentalancia <guido@trentalancia.com> 31 * 32 * Added support for runtime switching of the policy type 33 * 34 * Copyright (C) 2008, 2009 NEC Corporation 35 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 36 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. 37 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC 38 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> 39 */ 40 #include <linux/kernel.h> 41 #include <linux/slab.h> 42 #include <linux/string.h> 43 #include <linux/spinlock.h> 44 #include <linux/rcupdate.h> 45 #include <linux/errno.h> 46 #include <linux/in.h> 47 #include <linux/sched.h> 48 #include <linux/audit.h> 49 #include <linux/vmalloc.h> 50 #include <net/netlabel.h> 51 52 #include "flask.h" 53 #include "avc.h" 54 #include "avc_ss.h" 55 #include "security.h" 56 #include "context.h" 57 #include "policydb.h" 58 #include "sidtab.h" 59 #include "services.h" 60 #include "conditional.h" 61 #include "mls.h" 62 #include "objsec.h" 63 #include "netlabel.h" 64 #include "xfrm.h" 65 #include "ebitmap.h" 66 #include "audit.h" 67 68 /* Policy capability names */ 69 const char *selinux_policycap_names[__POLICYDB_CAPABILITY_MAX] = { 70 "network_peer_controls", 71 "open_perms", 72 "extended_socket_class", 73 "always_check_network", 74 "cgroup_seclabel", 75 "nnp_nosuid_transition", 76 "genfs_seclabel_symlinks" 77 }; 78 79 static struct selinux_ss selinux_ss; 80 81 void selinux_ss_init(struct selinux_ss **ss) 82 { 83 rwlock_init(&selinux_ss.policy_rwlock); 84 *ss = &selinux_ss; 85 } 86 87 /* Forward declaration. */ 88 static int context_struct_to_string(struct policydb *policydb, 89 struct context *context, 90 char **scontext, 91 u32 *scontext_len); 92 93 static int sidtab_entry_to_string(struct policydb *policydb, 94 struct sidtab *sidtab, 95 struct sidtab_entry *entry, 96 char **scontext, 97 u32 *scontext_len); 98 99 static void context_struct_compute_av(struct policydb *policydb, 100 struct context *scontext, 101 struct context *tcontext, 102 u16 tclass, 103 struct av_decision *avd, 104 struct extended_perms *xperms); 105 106 static int selinux_set_mapping(struct policydb *pol, 107 struct security_class_mapping *map, 108 struct selinux_map *out_map) 109 { 110 u16 i, j; 111 unsigned k; 112 bool print_unknown_handle = false; 113 114 /* Find number of classes in the input mapping */ 115 if (!map) 116 return -EINVAL; 117 i = 0; 118 while (map[i].name) 119 i++; 120 121 /* Allocate space for the class records, plus one for class zero */ 122 out_map->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC); 123 if (!out_map->mapping) 124 return -ENOMEM; 125 126 /* Store the raw class and permission values */ 127 j = 0; 128 while (map[j].name) { 129 struct security_class_mapping *p_in = map + (j++); 130 struct selinux_mapping *p_out = out_map->mapping + j; 131 132 /* An empty class string skips ahead */ 133 if (!strcmp(p_in->name, "")) { 134 p_out->num_perms = 0; 135 continue; 136 } 137 138 p_out->value = string_to_security_class(pol, p_in->name); 139 if (!p_out->value) { 140 pr_info("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 pr_info("SELinux: Permission %s in class %s not defined in policy.\n", 160 p_in->perms[k], p_in->name); 161 if (pol->reject_unknown) 162 goto err; 163 print_unknown_handle = true; 164 } 165 166 k++; 167 } 168 p_out->num_perms = k; 169 } 170 171 if (print_unknown_handle) 172 pr_info("SELinux: the above unknown classes and permissions will be %s\n", 173 pol->allow_unknown ? "allowed" : "denied"); 174 175 out_map->size = i; 176 return 0; 177 err: 178 kfree(out_map->mapping); 179 out_map->mapping = NULL; 180 return -EINVAL; 181 } 182 183 /* 184 * Get real, policy values from mapped values 185 */ 186 187 static u16 unmap_class(struct selinux_map *map, u16 tclass) 188 { 189 if (tclass < map->size) 190 return map->mapping[tclass].value; 191 192 return tclass; 193 } 194 195 /* 196 * Get kernel value for class from its policy value 197 */ 198 static u16 map_class(struct selinux_map *map, u16 pol_value) 199 { 200 u16 i; 201 202 for (i = 1; i < map->size; i++) { 203 if (map->mapping[i].value == pol_value) 204 return i; 205 } 206 207 return SECCLASS_NULL; 208 } 209 210 static void map_decision(struct selinux_map *map, 211 u16 tclass, struct av_decision *avd, 212 int allow_unknown) 213 { 214 if (tclass < map->size) { 215 struct selinux_mapping *mapping = &map->mapping[tclass]; 216 unsigned int i, n = mapping->num_perms; 217 u32 result; 218 219 for (i = 0, result = 0; i < n; i++) { 220 if (avd->allowed & mapping->perms[i]) 221 result |= 1<<i; 222 if (allow_unknown && !mapping->perms[i]) 223 result |= 1<<i; 224 } 225 avd->allowed = result; 226 227 for (i = 0, result = 0; i < n; i++) 228 if (avd->auditallow & mapping->perms[i]) 229 result |= 1<<i; 230 avd->auditallow = result; 231 232 for (i = 0, result = 0; i < n; i++) { 233 if (avd->auditdeny & mapping->perms[i]) 234 result |= 1<<i; 235 if (!allow_unknown && !mapping->perms[i]) 236 result |= 1<<i; 237 } 238 /* 239 * In case the kernel has a bug and requests a permission 240 * between num_perms and the maximum permission number, we 241 * should audit that denial 242 */ 243 for (; i < (sizeof(u32)*8); i++) 244 result |= 1<<i; 245 avd->auditdeny = result; 246 } 247 } 248 249 int security_mls_enabled(struct selinux_state *state) 250 { 251 struct policydb *p = &state->ss->policydb; 252 253 return p->mls_enabled; 254 } 255 256 /* 257 * Return the boolean value of a constraint expression 258 * when it is applied to the specified source and target 259 * security contexts. 260 * 261 * xcontext is a special beast... It is used by the validatetrans rules 262 * only. For these rules, scontext is the context before the transition, 263 * tcontext is the context after the transition, and xcontext is the context 264 * of the process performing the transition. All other callers of 265 * constraint_expr_eval should pass in NULL for xcontext. 266 */ 267 static int constraint_expr_eval(struct policydb *policydb, 268 struct context *scontext, 269 struct context *tcontext, 270 struct context *xcontext, 271 struct constraint_expr *cexpr) 272 { 273 u32 val1, val2; 274 struct context *c; 275 struct role_datum *r1, *r2; 276 struct mls_level *l1, *l2; 277 struct constraint_expr *e; 278 int s[CEXPR_MAXDEPTH]; 279 int sp = -1; 280 281 for (e = cexpr; e; e = e->next) { 282 switch (e->expr_type) { 283 case CEXPR_NOT: 284 BUG_ON(sp < 0); 285 s[sp] = !s[sp]; 286 break; 287 case CEXPR_AND: 288 BUG_ON(sp < 1); 289 sp--; 290 s[sp] &= s[sp + 1]; 291 break; 292 case CEXPR_OR: 293 BUG_ON(sp < 1); 294 sp--; 295 s[sp] |= s[sp + 1]; 296 break; 297 case CEXPR_ATTR: 298 if (sp == (CEXPR_MAXDEPTH - 1)) 299 return 0; 300 switch (e->attr) { 301 case CEXPR_USER: 302 val1 = scontext->user; 303 val2 = tcontext->user; 304 break; 305 case CEXPR_TYPE: 306 val1 = scontext->type; 307 val2 = tcontext->type; 308 break; 309 case CEXPR_ROLE: 310 val1 = scontext->role; 311 val2 = tcontext->role; 312 r1 = policydb->role_val_to_struct[val1 - 1]; 313 r2 = policydb->role_val_to_struct[val2 - 1]; 314 switch (e->op) { 315 case CEXPR_DOM: 316 s[++sp] = ebitmap_get_bit(&r1->dominates, 317 val2 - 1); 318 continue; 319 case CEXPR_DOMBY: 320 s[++sp] = ebitmap_get_bit(&r2->dominates, 321 val1 - 1); 322 continue; 323 case CEXPR_INCOMP: 324 s[++sp] = (!ebitmap_get_bit(&r1->dominates, 325 val2 - 1) && 326 !ebitmap_get_bit(&r2->dominates, 327 val1 - 1)); 328 continue; 329 default: 330 break; 331 } 332 break; 333 case CEXPR_L1L2: 334 l1 = &(scontext->range.level[0]); 335 l2 = &(tcontext->range.level[0]); 336 goto mls_ops; 337 case CEXPR_L1H2: 338 l1 = &(scontext->range.level[0]); 339 l2 = &(tcontext->range.level[1]); 340 goto mls_ops; 341 case CEXPR_H1L2: 342 l1 = &(scontext->range.level[1]); 343 l2 = &(tcontext->range.level[0]); 344 goto mls_ops; 345 case CEXPR_H1H2: 346 l1 = &(scontext->range.level[1]); 347 l2 = &(tcontext->range.level[1]); 348 goto mls_ops; 349 case CEXPR_L1H1: 350 l1 = &(scontext->range.level[0]); 351 l2 = &(scontext->range.level[1]); 352 goto mls_ops; 353 case CEXPR_L2H2: 354 l1 = &(tcontext->range.level[0]); 355 l2 = &(tcontext->range.level[1]); 356 goto mls_ops; 357 mls_ops: 358 switch (e->op) { 359 case CEXPR_EQ: 360 s[++sp] = mls_level_eq(l1, l2); 361 continue; 362 case CEXPR_NEQ: 363 s[++sp] = !mls_level_eq(l1, l2); 364 continue; 365 case CEXPR_DOM: 366 s[++sp] = mls_level_dom(l1, l2); 367 continue; 368 case CEXPR_DOMBY: 369 s[++sp] = mls_level_dom(l2, l1); 370 continue; 371 case CEXPR_INCOMP: 372 s[++sp] = mls_level_incomp(l2, l1); 373 continue; 374 default: 375 BUG(); 376 return 0; 377 } 378 break; 379 default: 380 BUG(); 381 return 0; 382 } 383 384 switch (e->op) { 385 case CEXPR_EQ: 386 s[++sp] = (val1 == val2); 387 break; 388 case CEXPR_NEQ: 389 s[++sp] = (val1 != val2); 390 break; 391 default: 392 BUG(); 393 return 0; 394 } 395 break; 396 case CEXPR_NAMES: 397 if (sp == (CEXPR_MAXDEPTH-1)) 398 return 0; 399 c = scontext; 400 if (e->attr & CEXPR_TARGET) 401 c = tcontext; 402 else if (e->attr & CEXPR_XTARGET) { 403 c = xcontext; 404 if (!c) { 405 BUG(); 406 return 0; 407 } 408 } 409 if (e->attr & CEXPR_USER) 410 val1 = c->user; 411 else if (e->attr & CEXPR_ROLE) 412 val1 = c->role; 413 else if (e->attr & CEXPR_TYPE) 414 val1 = c->type; 415 else { 416 BUG(); 417 return 0; 418 } 419 420 switch (e->op) { 421 case CEXPR_EQ: 422 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); 423 break; 424 case CEXPR_NEQ: 425 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); 426 break; 427 default: 428 BUG(); 429 return 0; 430 } 431 break; 432 default: 433 BUG(); 434 return 0; 435 } 436 } 437 438 BUG_ON(sp != 0); 439 return s[0]; 440 } 441 442 /* 443 * security_dump_masked_av - dumps masked permissions during 444 * security_compute_av due to RBAC, MLS/Constraint and Type bounds. 445 */ 446 static int dump_masked_av_helper(void *k, void *d, void *args) 447 { 448 struct perm_datum *pdatum = d; 449 char **permission_names = args; 450 451 BUG_ON(pdatum->value < 1 || pdatum->value > 32); 452 453 permission_names[pdatum->value - 1] = (char *)k; 454 455 return 0; 456 } 457 458 static void security_dump_masked_av(struct policydb *policydb, 459 struct context *scontext, 460 struct context *tcontext, 461 u16 tclass, 462 u32 permissions, 463 const char *reason) 464 { 465 struct common_datum *common_dat; 466 struct class_datum *tclass_dat; 467 struct audit_buffer *ab; 468 char *tclass_name; 469 char *scontext_name = NULL; 470 char *tcontext_name = NULL; 471 char *permission_names[32]; 472 int index; 473 u32 length; 474 bool need_comma = false; 475 476 if (!permissions) 477 return; 478 479 tclass_name = sym_name(policydb, SYM_CLASSES, tclass - 1); 480 tclass_dat = policydb->class_val_to_struct[tclass - 1]; 481 common_dat = tclass_dat->comdatum; 482 483 /* init permission_names */ 484 if (common_dat && 485 hashtab_map(&common_dat->permissions.table, 486 dump_masked_av_helper, permission_names) < 0) 487 goto out; 488 489 if (hashtab_map(&tclass_dat->permissions.table, 490 dump_masked_av_helper, permission_names) < 0) 491 goto out; 492 493 /* get scontext/tcontext in text form */ 494 if (context_struct_to_string(policydb, scontext, 495 &scontext_name, &length) < 0) 496 goto out; 497 498 if (context_struct_to_string(policydb, tcontext, 499 &tcontext_name, &length) < 0) 500 goto out; 501 502 /* audit a message */ 503 ab = audit_log_start(audit_context(), 504 GFP_ATOMIC, AUDIT_SELINUX_ERR); 505 if (!ab) 506 goto out; 507 508 audit_log_format(ab, "op=security_compute_av reason=%s " 509 "scontext=%s tcontext=%s tclass=%s perms=", 510 reason, scontext_name, tcontext_name, tclass_name); 511 512 for (index = 0; index < 32; index++) { 513 u32 mask = (1 << index); 514 515 if ((mask & permissions) == 0) 516 continue; 517 518 audit_log_format(ab, "%s%s", 519 need_comma ? "," : "", 520 permission_names[index] 521 ? permission_names[index] : "????"); 522 need_comma = true; 523 } 524 audit_log_end(ab); 525 out: 526 /* release scontext/tcontext */ 527 kfree(tcontext_name); 528 kfree(scontext_name); 529 530 return; 531 } 532 533 /* 534 * security_boundary_permission - drops violated permissions 535 * on boundary constraint. 536 */ 537 static void type_attribute_bounds_av(struct policydb *policydb, 538 struct context *scontext, 539 struct context *tcontext, 540 u16 tclass, 541 struct av_decision *avd) 542 { 543 struct context lo_scontext; 544 struct context lo_tcontext, *tcontextp = tcontext; 545 struct av_decision lo_avd; 546 struct type_datum *source; 547 struct type_datum *target; 548 u32 masked = 0; 549 550 source = policydb->type_val_to_struct[scontext->type - 1]; 551 BUG_ON(!source); 552 553 if (!source->bounds) 554 return; 555 556 target = policydb->type_val_to_struct[tcontext->type - 1]; 557 BUG_ON(!target); 558 559 memset(&lo_avd, 0, sizeof(lo_avd)); 560 561 memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); 562 lo_scontext.type = source->bounds; 563 564 if (target->bounds) { 565 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); 566 lo_tcontext.type = target->bounds; 567 tcontextp = &lo_tcontext; 568 } 569 570 context_struct_compute_av(policydb, &lo_scontext, 571 tcontextp, 572 tclass, 573 &lo_avd, 574 NULL); 575 576 masked = ~lo_avd.allowed & avd->allowed; 577 578 if (likely(!masked)) 579 return; /* no masked permission */ 580 581 /* mask violated permissions */ 582 avd->allowed &= ~masked; 583 584 /* audit masked permissions */ 585 security_dump_masked_av(policydb, scontext, tcontext, 586 tclass, masked, "bounds"); 587 } 588 589 /* 590 * flag which drivers have permissions 591 * only looking for ioctl based extended permssions 592 */ 593 void services_compute_xperms_drivers( 594 struct extended_perms *xperms, 595 struct avtab_node *node) 596 { 597 unsigned int i; 598 599 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 600 /* if one or more driver has all permissions allowed */ 601 for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++) 602 xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i]; 603 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 604 /* if allowing permissions within a driver */ 605 security_xperm_set(xperms->drivers.p, 606 node->datum.u.xperms->driver); 607 } 608 609 /* If no ioctl commands are allowed, ignore auditallow and auditdeny */ 610 if (node->key.specified & AVTAB_XPERMS_ALLOWED) 611 xperms->len = 1; 612 } 613 614 /* 615 * Compute access vectors and extended permissions based on a context 616 * structure pair for the permissions in a particular class. 617 */ 618 static void context_struct_compute_av(struct policydb *policydb, 619 struct context *scontext, 620 struct context *tcontext, 621 u16 tclass, 622 struct av_decision *avd, 623 struct extended_perms *xperms) 624 { 625 struct constraint_node *constraint; 626 struct role_allow *ra; 627 struct avtab_key avkey; 628 struct avtab_node *node; 629 struct class_datum *tclass_datum; 630 struct ebitmap *sattr, *tattr; 631 struct ebitmap_node *snode, *tnode; 632 unsigned int i, j; 633 634 avd->allowed = 0; 635 avd->auditallow = 0; 636 avd->auditdeny = 0xffffffff; 637 if (xperms) { 638 memset(&xperms->drivers, 0, sizeof(xperms->drivers)); 639 xperms->len = 0; 640 } 641 642 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { 643 if (printk_ratelimit()) 644 pr_warn("SELinux: Invalid class %hu\n", tclass); 645 return; 646 } 647 648 tclass_datum = policydb->class_val_to_struct[tclass - 1]; 649 650 /* 651 * If a specific type enforcement rule was defined for 652 * this permission check, then use it. 653 */ 654 avkey.target_class = tclass; 655 avkey.specified = AVTAB_AV | AVTAB_XPERMS; 656 sattr = &policydb->type_attr_map_array[scontext->type - 1]; 657 tattr = &policydb->type_attr_map_array[tcontext->type - 1]; 658 ebitmap_for_each_positive_bit(sattr, snode, i) { 659 ebitmap_for_each_positive_bit(tattr, tnode, j) { 660 avkey.source_type = i + 1; 661 avkey.target_type = j + 1; 662 for (node = avtab_search_node(&policydb->te_avtab, 663 &avkey); 664 node; 665 node = avtab_search_node_next(node, avkey.specified)) { 666 if (node->key.specified == AVTAB_ALLOWED) 667 avd->allowed |= node->datum.u.data; 668 else if (node->key.specified == AVTAB_AUDITALLOW) 669 avd->auditallow |= node->datum.u.data; 670 else if (node->key.specified == AVTAB_AUDITDENY) 671 avd->auditdeny &= node->datum.u.data; 672 else if (xperms && (node->key.specified & AVTAB_XPERMS)) 673 services_compute_xperms_drivers(xperms, node); 674 } 675 676 /* Check conditional av table for additional permissions */ 677 cond_compute_av(&policydb->te_cond_avtab, &avkey, 678 avd, xperms); 679 680 } 681 } 682 683 /* 684 * Remove any permissions prohibited by a constraint (this includes 685 * the MLS policy). 686 */ 687 constraint = tclass_datum->constraints; 688 while (constraint) { 689 if ((constraint->permissions & (avd->allowed)) && 690 !constraint_expr_eval(policydb, scontext, tcontext, NULL, 691 constraint->expr)) { 692 avd->allowed &= ~(constraint->permissions); 693 } 694 constraint = constraint->next; 695 } 696 697 /* 698 * If checking process transition permission and the 699 * role is changing, then check the (current_role, new_role) 700 * pair. 701 */ 702 if (tclass == policydb->process_class && 703 (avd->allowed & policydb->process_trans_perms) && 704 scontext->role != tcontext->role) { 705 for (ra = policydb->role_allow; ra; ra = ra->next) { 706 if (scontext->role == ra->role && 707 tcontext->role == ra->new_role) 708 break; 709 } 710 if (!ra) 711 avd->allowed &= ~policydb->process_trans_perms; 712 } 713 714 /* 715 * If the given source and target types have boundary 716 * constraint, lazy checks have to mask any violated 717 * permission and notice it to userspace via audit. 718 */ 719 type_attribute_bounds_av(policydb, scontext, tcontext, 720 tclass, avd); 721 } 722 723 static int security_validtrans_handle_fail(struct selinux_state *state, 724 struct sidtab_entry *oentry, 725 struct sidtab_entry *nentry, 726 struct sidtab_entry *tentry, 727 u16 tclass) 728 { 729 struct policydb *p = &state->ss->policydb; 730 struct sidtab *sidtab = state->ss->sidtab; 731 char *o = NULL, *n = NULL, *t = NULL; 732 u32 olen, nlen, tlen; 733 734 if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen)) 735 goto out; 736 if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen)) 737 goto out; 738 if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen)) 739 goto out; 740 audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, 741 "op=security_validate_transition seresult=denied" 742 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", 743 o, n, t, sym_name(p, SYM_CLASSES, tclass-1)); 744 out: 745 kfree(o); 746 kfree(n); 747 kfree(t); 748 749 if (!enforcing_enabled(state)) 750 return 0; 751 return -EPERM; 752 } 753 754 static int security_compute_validatetrans(struct selinux_state *state, 755 u32 oldsid, u32 newsid, u32 tasksid, 756 u16 orig_tclass, bool user) 757 { 758 struct policydb *policydb; 759 struct sidtab *sidtab; 760 struct sidtab_entry *oentry; 761 struct sidtab_entry *nentry; 762 struct sidtab_entry *tentry; 763 struct class_datum *tclass_datum; 764 struct constraint_node *constraint; 765 u16 tclass; 766 int rc = 0; 767 768 769 if (!selinux_initialized(state)) 770 return 0; 771 772 read_lock(&state->ss->policy_rwlock); 773 774 policydb = &state->ss->policydb; 775 sidtab = state->ss->sidtab; 776 777 if (!user) 778 tclass = unmap_class(&state->ss->map, orig_tclass); 779 else 780 tclass = orig_tclass; 781 782 if (!tclass || tclass > policydb->p_classes.nprim) { 783 rc = -EINVAL; 784 goto out; 785 } 786 tclass_datum = policydb->class_val_to_struct[tclass - 1]; 787 788 oentry = sidtab_search_entry(sidtab, oldsid); 789 if (!oentry) { 790 pr_err("SELinux: %s: unrecognized SID %d\n", 791 __func__, oldsid); 792 rc = -EINVAL; 793 goto out; 794 } 795 796 nentry = sidtab_search_entry(sidtab, newsid); 797 if (!nentry) { 798 pr_err("SELinux: %s: unrecognized SID %d\n", 799 __func__, newsid); 800 rc = -EINVAL; 801 goto out; 802 } 803 804 tentry = sidtab_search_entry(sidtab, tasksid); 805 if (!tentry) { 806 pr_err("SELinux: %s: unrecognized SID %d\n", 807 __func__, tasksid); 808 rc = -EINVAL; 809 goto out; 810 } 811 812 constraint = tclass_datum->validatetrans; 813 while (constraint) { 814 if (!constraint_expr_eval(policydb, &oentry->context, 815 &nentry->context, &tentry->context, 816 constraint->expr)) { 817 if (user) 818 rc = -EPERM; 819 else 820 rc = security_validtrans_handle_fail(state, 821 oentry, 822 nentry, 823 tentry, 824 tclass); 825 goto out; 826 } 827 constraint = constraint->next; 828 } 829 830 out: 831 read_unlock(&state->ss->policy_rwlock); 832 return rc; 833 } 834 835 int security_validate_transition_user(struct selinux_state *state, 836 u32 oldsid, u32 newsid, u32 tasksid, 837 u16 tclass) 838 { 839 return security_compute_validatetrans(state, oldsid, newsid, tasksid, 840 tclass, true); 841 } 842 843 int security_validate_transition(struct selinux_state *state, 844 u32 oldsid, u32 newsid, u32 tasksid, 845 u16 orig_tclass) 846 { 847 return security_compute_validatetrans(state, oldsid, newsid, tasksid, 848 orig_tclass, false); 849 } 850 851 /* 852 * security_bounded_transition - check whether the given 853 * transition is directed to bounded, or not. 854 * It returns 0, if @newsid is bounded by @oldsid. 855 * Otherwise, it returns error code. 856 * 857 * @oldsid : current security identifier 858 * @newsid : destinated security identifier 859 */ 860 int security_bounded_transition(struct selinux_state *state, 861 u32 old_sid, u32 new_sid) 862 { 863 struct policydb *policydb; 864 struct sidtab *sidtab; 865 struct sidtab_entry *old_entry, *new_entry; 866 struct type_datum *type; 867 int index; 868 int rc; 869 870 if (!selinux_initialized(state)) 871 return 0; 872 873 read_lock(&state->ss->policy_rwlock); 874 875 policydb = &state->ss->policydb; 876 sidtab = state->ss->sidtab; 877 878 rc = -EINVAL; 879 old_entry = sidtab_search_entry(sidtab, old_sid); 880 if (!old_entry) { 881 pr_err("SELinux: %s: unrecognized SID %u\n", 882 __func__, old_sid); 883 goto out; 884 } 885 886 rc = -EINVAL; 887 new_entry = sidtab_search_entry(sidtab, new_sid); 888 if (!new_entry) { 889 pr_err("SELinux: %s: unrecognized SID %u\n", 890 __func__, new_sid); 891 goto out; 892 } 893 894 rc = 0; 895 /* type/domain unchanged */ 896 if (old_entry->context.type == new_entry->context.type) 897 goto out; 898 899 index = new_entry->context.type; 900 while (true) { 901 type = policydb->type_val_to_struct[index - 1]; 902 BUG_ON(!type); 903 904 /* not bounded anymore */ 905 rc = -EPERM; 906 if (!type->bounds) 907 break; 908 909 /* @newsid is bounded by @oldsid */ 910 rc = 0; 911 if (type->bounds == old_entry->context.type) 912 break; 913 914 index = type->bounds; 915 } 916 917 if (rc) { 918 char *old_name = NULL; 919 char *new_name = NULL; 920 u32 length; 921 922 if (!sidtab_entry_to_string(policydb, sidtab, old_entry, 923 &old_name, &length) && 924 !sidtab_entry_to_string(policydb, sidtab, new_entry, 925 &new_name, &length)) { 926 audit_log(audit_context(), 927 GFP_ATOMIC, AUDIT_SELINUX_ERR, 928 "op=security_bounded_transition " 929 "seresult=denied " 930 "oldcontext=%s newcontext=%s", 931 old_name, new_name); 932 } 933 kfree(new_name); 934 kfree(old_name); 935 } 936 out: 937 read_unlock(&state->ss->policy_rwlock); 938 939 return rc; 940 } 941 942 static void avd_init(struct selinux_state *state, struct av_decision *avd) 943 { 944 avd->allowed = 0; 945 avd->auditallow = 0; 946 avd->auditdeny = 0xffffffff; 947 avd->seqno = state->ss->latest_granting; 948 avd->flags = 0; 949 } 950 951 void services_compute_xperms_decision(struct extended_perms_decision *xpermd, 952 struct avtab_node *node) 953 { 954 unsigned int i; 955 956 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 957 if (xpermd->driver != node->datum.u.xperms->driver) 958 return; 959 } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 960 if (!security_xperm_test(node->datum.u.xperms->perms.p, 961 xpermd->driver)) 962 return; 963 } else { 964 BUG(); 965 } 966 967 if (node->key.specified == AVTAB_XPERMS_ALLOWED) { 968 xpermd->used |= XPERMS_ALLOWED; 969 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 970 memset(xpermd->allowed->p, 0xff, 971 sizeof(xpermd->allowed->p)); 972 } 973 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 974 for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++) 975 xpermd->allowed->p[i] |= 976 node->datum.u.xperms->perms.p[i]; 977 } 978 } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) { 979 xpermd->used |= XPERMS_AUDITALLOW; 980 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 981 memset(xpermd->auditallow->p, 0xff, 982 sizeof(xpermd->auditallow->p)); 983 } 984 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 985 for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++) 986 xpermd->auditallow->p[i] |= 987 node->datum.u.xperms->perms.p[i]; 988 } 989 } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) { 990 xpermd->used |= XPERMS_DONTAUDIT; 991 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { 992 memset(xpermd->dontaudit->p, 0xff, 993 sizeof(xpermd->dontaudit->p)); 994 } 995 if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { 996 for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++) 997 xpermd->dontaudit->p[i] |= 998 node->datum.u.xperms->perms.p[i]; 999 } 1000 } else { 1001 BUG(); 1002 } 1003 } 1004 1005 void security_compute_xperms_decision(struct selinux_state *state, 1006 u32 ssid, 1007 u32 tsid, 1008 u16 orig_tclass, 1009 u8 driver, 1010 struct extended_perms_decision *xpermd) 1011 { 1012 struct policydb *policydb; 1013 struct sidtab *sidtab; 1014 u16 tclass; 1015 struct context *scontext, *tcontext; 1016 struct avtab_key avkey; 1017 struct avtab_node *node; 1018 struct ebitmap *sattr, *tattr; 1019 struct ebitmap_node *snode, *tnode; 1020 unsigned int i, j; 1021 1022 xpermd->driver = driver; 1023 xpermd->used = 0; 1024 memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p)); 1025 memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); 1026 memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); 1027 1028 read_lock(&state->ss->policy_rwlock); 1029 if (!selinux_initialized(state)) 1030 goto allow; 1031 1032 policydb = &state->ss->policydb; 1033 sidtab = state->ss->sidtab; 1034 1035 scontext = sidtab_search(sidtab, ssid); 1036 if (!scontext) { 1037 pr_err("SELinux: %s: unrecognized SID %d\n", 1038 __func__, ssid); 1039 goto out; 1040 } 1041 1042 tcontext = sidtab_search(sidtab, tsid); 1043 if (!tcontext) { 1044 pr_err("SELinux: %s: unrecognized SID %d\n", 1045 __func__, tsid); 1046 goto out; 1047 } 1048 1049 tclass = unmap_class(&state->ss->map, orig_tclass); 1050 if (unlikely(orig_tclass && !tclass)) { 1051 if (policydb->allow_unknown) 1052 goto allow; 1053 goto out; 1054 } 1055 1056 1057 if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { 1058 pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass); 1059 goto out; 1060 } 1061 1062 avkey.target_class = tclass; 1063 avkey.specified = AVTAB_XPERMS; 1064 sattr = &policydb->type_attr_map_array[scontext->type - 1]; 1065 tattr = &policydb->type_attr_map_array[tcontext->type - 1]; 1066 ebitmap_for_each_positive_bit(sattr, snode, i) { 1067 ebitmap_for_each_positive_bit(tattr, tnode, j) { 1068 avkey.source_type = i + 1; 1069 avkey.target_type = j + 1; 1070 for (node = avtab_search_node(&policydb->te_avtab, 1071 &avkey); 1072 node; 1073 node = avtab_search_node_next(node, avkey.specified)) 1074 services_compute_xperms_decision(xpermd, node); 1075 1076 cond_compute_xperms(&policydb->te_cond_avtab, 1077 &avkey, xpermd); 1078 } 1079 } 1080 out: 1081 read_unlock(&state->ss->policy_rwlock); 1082 return; 1083 allow: 1084 memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); 1085 goto out; 1086 } 1087 1088 /** 1089 * security_compute_av - Compute access vector decisions. 1090 * @ssid: source security identifier 1091 * @tsid: target security identifier 1092 * @tclass: target security class 1093 * @avd: access vector decisions 1094 * @xperms: extended permissions 1095 * 1096 * Compute a set of access vector decisions based on the 1097 * SID pair (@ssid, @tsid) for the permissions in @tclass. 1098 */ 1099 void security_compute_av(struct selinux_state *state, 1100 u32 ssid, 1101 u32 tsid, 1102 u16 orig_tclass, 1103 struct av_decision *avd, 1104 struct extended_perms *xperms) 1105 { 1106 struct policydb *policydb; 1107 struct sidtab *sidtab; 1108 u16 tclass; 1109 struct context *scontext = NULL, *tcontext = NULL; 1110 1111 read_lock(&state->ss->policy_rwlock); 1112 avd_init(state, avd); 1113 xperms->len = 0; 1114 if (!selinux_initialized(state)) 1115 goto allow; 1116 1117 policydb = &state->ss->policydb; 1118 sidtab = state->ss->sidtab; 1119 1120 scontext = sidtab_search(sidtab, ssid); 1121 if (!scontext) { 1122 pr_err("SELinux: %s: unrecognized SID %d\n", 1123 __func__, ssid); 1124 goto out; 1125 } 1126 1127 /* permissive domain? */ 1128 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type)) 1129 avd->flags |= AVD_FLAGS_PERMISSIVE; 1130 1131 tcontext = sidtab_search(sidtab, tsid); 1132 if (!tcontext) { 1133 pr_err("SELinux: %s: unrecognized SID %d\n", 1134 __func__, tsid); 1135 goto out; 1136 } 1137 1138 tclass = unmap_class(&state->ss->map, orig_tclass); 1139 if (unlikely(orig_tclass && !tclass)) { 1140 if (policydb->allow_unknown) 1141 goto allow; 1142 goto out; 1143 } 1144 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, 1145 xperms); 1146 map_decision(&state->ss->map, orig_tclass, avd, 1147 policydb->allow_unknown); 1148 out: 1149 read_unlock(&state->ss->policy_rwlock); 1150 return; 1151 allow: 1152 avd->allowed = 0xffffffff; 1153 goto out; 1154 } 1155 1156 void security_compute_av_user(struct selinux_state *state, 1157 u32 ssid, 1158 u32 tsid, 1159 u16 tclass, 1160 struct av_decision *avd) 1161 { 1162 struct policydb *policydb; 1163 struct sidtab *sidtab; 1164 struct context *scontext = NULL, *tcontext = NULL; 1165 1166 read_lock(&state->ss->policy_rwlock); 1167 avd_init(state, avd); 1168 if (!selinux_initialized(state)) 1169 goto allow; 1170 1171 policydb = &state->ss->policydb; 1172 sidtab = state->ss->sidtab; 1173 1174 scontext = sidtab_search(sidtab, ssid); 1175 if (!scontext) { 1176 pr_err("SELinux: %s: unrecognized SID %d\n", 1177 __func__, ssid); 1178 goto out; 1179 } 1180 1181 /* permissive domain? */ 1182 if (ebitmap_get_bit(&policydb->permissive_map, scontext->type)) 1183 avd->flags |= AVD_FLAGS_PERMISSIVE; 1184 1185 tcontext = sidtab_search(sidtab, tsid); 1186 if (!tcontext) { 1187 pr_err("SELinux: %s: unrecognized SID %d\n", 1188 __func__, tsid); 1189 goto out; 1190 } 1191 1192 if (unlikely(!tclass)) { 1193 if (policydb->allow_unknown) 1194 goto allow; 1195 goto out; 1196 } 1197 1198 context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, 1199 NULL); 1200 out: 1201 read_unlock(&state->ss->policy_rwlock); 1202 return; 1203 allow: 1204 avd->allowed = 0xffffffff; 1205 goto out; 1206 } 1207 1208 /* 1209 * Write the security context string representation of 1210 * the context structure `context' into a dynamically 1211 * allocated string of the correct size. Set `*scontext' 1212 * to point to this string and set `*scontext_len' to 1213 * the length of the string. 1214 */ 1215 static int context_struct_to_string(struct policydb *p, 1216 struct context *context, 1217 char **scontext, u32 *scontext_len) 1218 { 1219 char *scontextp; 1220 1221 if (scontext) 1222 *scontext = NULL; 1223 *scontext_len = 0; 1224 1225 if (context->len) { 1226 *scontext_len = context->len; 1227 if (scontext) { 1228 *scontext = kstrdup(context->str, GFP_ATOMIC); 1229 if (!(*scontext)) 1230 return -ENOMEM; 1231 } 1232 return 0; 1233 } 1234 1235 /* Compute the size of the context. */ 1236 *scontext_len += strlen(sym_name(p, SYM_USERS, context->user - 1)) + 1; 1237 *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1; 1238 *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1; 1239 *scontext_len += mls_compute_context_len(p, context); 1240 1241 if (!scontext) 1242 return 0; 1243 1244 /* Allocate space for the context; caller must free this space. */ 1245 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1246 if (!scontextp) 1247 return -ENOMEM; 1248 *scontext = scontextp; 1249 1250 /* 1251 * Copy the user name, role name and type name into the context. 1252 */ 1253 scontextp += sprintf(scontextp, "%s:%s:%s", 1254 sym_name(p, SYM_USERS, context->user - 1), 1255 sym_name(p, SYM_ROLES, context->role - 1), 1256 sym_name(p, SYM_TYPES, context->type - 1)); 1257 1258 mls_sid_to_context(p, context, &scontextp); 1259 1260 *scontextp = 0; 1261 1262 return 0; 1263 } 1264 1265 static int sidtab_entry_to_string(struct policydb *p, 1266 struct sidtab *sidtab, 1267 struct sidtab_entry *entry, 1268 char **scontext, u32 *scontext_len) 1269 { 1270 int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len); 1271 1272 if (rc != -ENOENT) 1273 return rc; 1274 1275 rc = context_struct_to_string(p, &entry->context, scontext, 1276 scontext_len); 1277 if (!rc && scontext) 1278 sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len); 1279 return rc; 1280 } 1281 1282 #include "initial_sid_to_string.h" 1283 1284 int security_sidtab_hash_stats(struct selinux_state *state, char *page) 1285 { 1286 int rc; 1287 1288 if (!selinux_initialized(state)) { 1289 pr_err("SELinux: %s: called before initial load_policy\n", 1290 __func__); 1291 return -EINVAL; 1292 } 1293 1294 read_lock(&state->ss->policy_rwlock); 1295 rc = sidtab_hash_stats(state->ss->sidtab, page); 1296 read_unlock(&state->ss->policy_rwlock); 1297 1298 return rc; 1299 } 1300 1301 const char *security_get_initial_sid_context(u32 sid) 1302 { 1303 if (unlikely(sid > SECINITSID_NUM)) 1304 return NULL; 1305 return initial_sid_to_string[sid]; 1306 } 1307 1308 static int security_sid_to_context_core(struct selinux_state *state, 1309 u32 sid, char **scontext, 1310 u32 *scontext_len, int force, 1311 int only_invalid) 1312 { 1313 struct policydb *policydb; 1314 struct sidtab *sidtab; 1315 struct sidtab_entry *entry; 1316 int rc = 0; 1317 1318 if (scontext) 1319 *scontext = NULL; 1320 *scontext_len = 0; 1321 1322 if (!selinux_initialized(state)) { 1323 if (sid <= SECINITSID_NUM) { 1324 char *scontextp; 1325 const char *s = initial_sid_to_string[sid]; 1326 1327 if (!s) 1328 return -EINVAL; 1329 *scontext_len = strlen(s) + 1; 1330 if (!scontext) 1331 return 0; 1332 scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC); 1333 if (!scontextp) 1334 return -ENOMEM; 1335 *scontext = scontextp; 1336 return 0; 1337 } 1338 pr_err("SELinux: %s: called before initial " 1339 "load_policy on unknown SID %d\n", __func__, sid); 1340 return -EINVAL; 1341 } 1342 read_lock(&state->ss->policy_rwlock); 1343 policydb = &state->ss->policydb; 1344 sidtab = state->ss->sidtab; 1345 1346 if (force) 1347 entry = sidtab_search_entry_force(sidtab, sid); 1348 else 1349 entry = sidtab_search_entry(sidtab, sid); 1350 if (!entry) { 1351 pr_err("SELinux: %s: unrecognized SID %d\n", 1352 __func__, sid); 1353 rc = -EINVAL; 1354 goto out_unlock; 1355 } 1356 if (only_invalid && !entry->context.len) 1357 goto out_unlock; 1358 1359 rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext, 1360 scontext_len); 1361 1362 out_unlock: 1363 read_unlock(&state->ss->policy_rwlock); 1364 return rc; 1365 1366 } 1367 1368 /** 1369 * security_sid_to_context - Obtain a context for a given SID. 1370 * @sid: security identifier, SID 1371 * @scontext: security context 1372 * @scontext_len: length in bytes 1373 * 1374 * Write the string representation of the context associated with @sid 1375 * into a dynamically allocated string of the correct size. Set @scontext 1376 * to point to this string and set @scontext_len to the length of the string. 1377 */ 1378 int security_sid_to_context(struct selinux_state *state, 1379 u32 sid, char **scontext, u32 *scontext_len) 1380 { 1381 return security_sid_to_context_core(state, sid, scontext, 1382 scontext_len, 0, 0); 1383 } 1384 1385 int security_sid_to_context_force(struct selinux_state *state, u32 sid, 1386 char **scontext, u32 *scontext_len) 1387 { 1388 return security_sid_to_context_core(state, sid, scontext, 1389 scontext_len, 1, 0); 1390 } 1391 1392 /** 1393 * security_sid_to_context_inval - Obtain a context for a given SID if it 1394 * is invalid. 1395 * @sid: security identifier, SID 1396 * @scontext: security context 1397 * @scontext_len: length in bytes 1398 * 1399 * Write the string representation of the context associated with @sid 1400 * into a dynamically allocated string of the correct size, but only if the 1401 * context is invalid in the current policy. Set @scontext to point to 1402 * this string (or NULL if the context is valid) and set @scontext_len to 1403 * the length of the string (or 0 if the context is valid). 1404 */ 1405 int security_sid_to_context_inval(struct selinux_state *state, u32 sid, 1406 char **scontext, u32 *scontext_len) 1407 { 1408 return security_sid_to_context_core(state, sid, scontext, 1409 scontext_len, 1, 1); 1410 } 1411 1412 /* 1413 * Caveat: Mutates scontext. 1414 */ 1415 static int string_to_context_struct(struct policydb *pol, 1416 struct sidtab *sidtabp, 1417 char *scontext, 1418 struct context *ctx, 1419 u32 def_sid) 1420 { 1421 struct role_datum *role; 1422 struct type_datum *typdatum; 1423 struct user_datum *usrdatum; 1424 char *scontextp, *p, oldc; 1425 int rc = 0; 1426 1427 context_init(ctx); 1428 1429 /* Parse the security context. */ 1430 1431 rc = -EINVAL; 1432 scontextp = (char *) scontext; 1433 1434 /* Extract the user. */ 1435 p = scontextp; 1436 while (*p && *p != ':') 1437 p++; 1438 1439 if (*p == 0) 1440 goto out; 1441 1442 *p++ = 0; 1443 1444 usrdatum = symtab_search(&pol->p_users, scontextp); 1445 if (!usrdatum) 1446 goto out; 1447 1448 ctx->user = usrdatum->value; 1449 1450 /* Extract role. */ 1451 scontextp = p; 1452 while (*p && *p != ':') 1453 p++; 1454 1455 if (*p == 0) 1456 goto out; 1457 1458 *p++ = 0; 1459 1460 role = symtab_search(&pol->p_roles, scontextp); 1461 if (!role) 1462 goto out; 1463 ctx->role = role->value; 1464 1465 /* Extract type. */ 1466 scontextp = p; 1467 while (*p && *p != ':') 1468 p++; 1469 oldc = *p; 1470 *p++ = 0; 1471 1472 typdatum = symtab_search(&pol->p_types, scontextp); 1473 if (!typdatum || typdatum->attribute) 1474 goto out; 1475 1476 ctx->type = typdatum->value; 1477 1478 rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid); 1479 if (rc) 1480 goto out; 1481 1482 /* Check the validity of the new context. */ 1483 rc = -EINVAL; 1484 if (!policydb_context_isvalid(pol, ctx)) 1485 goto out; 1486 rc = 0; 1487 out: 1488 if (rc) 1489 context_destroy(ctx); 1490 return rc; 1491 } 1492 1493 static int security_context_to_sid_core(struct selinux_state *state, 1494 const char *scontext, u32 scontext_len, 1495 u32 *sid, u32 def_sid, gfp_t gfp_flags, 1496 int force) 1497 { 1498 struct policydb *policydb; 1499 struct sidtab *sidtab; 1500 char *scontext2, *str = NULL; 1501 struct context context; 1502 int rc = 0; 1503 1504 /* An empty security context is never valid. */ 1505 if (!scontext_len) 1506 return -EINVAL; 1507 1508 /* Copy the string to allow changes and ensure a NUL terminator */ 1509 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags); 1510 if (!scontext2) 1511 return -ENOMEM; 1512 1513 if (!selinux_initialized(state)) { 1514 int i; 1515 1516 for (i = 1; i < SECINITSID_NUM; i++) { 1517 const char *s = initial_sid_to_string[i]; 1518 1519 if (s && !strcmp(s, scontext2)) { 1520 *sid = i; 1521 goto out; 1522 } 1523 } 1524 *sid = SECINITSID_KERNEL; 1525 goto out; 1526 } 1527 *sid = SECSID_NULL; 1528 1529 if (force) { 1530 /* Save another copy for storing in uninterpreted form */ 1531 rc = -ENOMEM; 1532 str = kstrdup(scontext2, gfp_flags); 1533 if (!str) 1534 goto out; 1535 } 1536 read_lock(&state->ss->policy_rwlock); 1537 policydb = &state->ss->policydb; 1538 sidtab = state->ss->sidtab; 1539 rc = string_to_context_struct(policydb, sidtab, scontext2, 1540 &context, def_sid); 1541 if (rc == -EINVAL && force) { 1542 context.str = str; 1543 context.len = strlen(str) + 1; 1544 str = NULL; 1545 } else if (rc) 1546 goto out_unlock; 1547 rc = sidtab_context_to_sid(sidtab, &context, sid); 1548 context_destroy(&context); 1549 out_unlock: 1550 read_unlock(&state->ss->policy_rwlock); 1551 out: 1552 kfree(scontext2); 1553 kfree(str); 1554 return rc; 1555 } 1556 1557 /** 1558 * security_context_to_sid - Obtain a SID for a given security context. 1559 * @scontext: security context 1560 * @scontext_len: length in bytes 1561 * @sid: security identifier, SID 1562 * @gfp: context for the allocation 1563 * 1564 * Obtains a SID associated with the security context that 1565 * has the string representation specified by @scontext. 1566 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1567 * memory is available, or 0 on success. 1568 */ 1569 int security_context_to_sid(struct selinux_state *state, 1570 const char *scontext, u32 scontext_len, u32 *sid, 1571 gfp_t gfp) 1572 { 1573 return security_context_to_sid_core(state, scontext, scontext_len, 1574 sid, SECSID_NULL, gfp, 0); 1575 } 1576 1577 int security_context_str_to_sid(struct selinux_state *state, 1578 const char *scontext, u32 *sid, gfp_t gfp) 1579 { 1580 return security_context_to_sid(state, scontext, strlen(scontext), 1581 sid, gfp); 1582 } 1583 1584 /** 1585 * security_context_to_sid_default - Obtain a SID for a given security context, 1586 * falling back to specified default if needed. 1587 * 1588 * @scontext: security context 1589 * @scontext_len: length in bytes 1590 * @sid: security identifier, SID 1591 * @def_sid: default SID to assign on error 1592 * 1593 * Obtains a SID associated with the security context that 1594 * has the string representation specified by @scontext. 1595 * The default SID is passed to the MLS layer to be used to allow 1596 * kernel labeling of the MLS field if the MLS field is not present 1597 * (for upgrading to MLS without full relabel). 1598 * Implicitly forces adding of the context even if it cannot be mapped yet. 1599 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1600 * memory is available, or 0 on success. 1601 */ 1602 int security_context_to_sid_default(struct selinux_state *state, 1603 const char *scontext, u32 scontext_len, 1604 u32 *sid, u32 def_sid, gfp_t gfp_flags) 1605 { 1606 return security_context_to_sid_core(state, scontext, scontext_len, 1607 sid, def_sid, gfp_flags, 1); 1608 } 1609 1610 int security_context_to_sid_force(struct selinux_state *state, 1611 const char *scontext, u32 scontext_len, 1612 u32 *sid) 1613 { 1614 return security_context_to_sid_core(state, scontext, scontext_len, 1615 sid, SECSID_NULL, GFP_KERNEL, 1); 1616 } 1617 1618 static int compute_sid_handle_invalid_context( 1619 struct selinux_state *state, 1620 struct sidtab_entry *sentry, 1621 struct sidtab_entry *tentry, 1622 u16 tclass, 1623 struct context *newcontext) 1624 { 1625 struct policydb *policydb = &state->ss->policydb; 1626 struct sidtab *sidtab = state->ss->sidtab; 1627 char *s = NULL, *t = NULL, *n = NULL; 1628 u32 slen, tlen, nlen; 1629 struct audit_buffer *ab; 1630 1631 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen)) 1632 goto out; 1633 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen)) 1634 goto out; 1635 if (context_struct_to_string(policydb, newcontext, &n, &nlen)) 1636 goto out; 1637 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); 1638 audit_log_format(ab, 1639 "op=security_compute_sid invalid_context="); 1640 /* no need to record the NUL with untrusted strings */ 1641 audit_log_n_untrustedstring(ab, n, nlen - 1); 1642 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s", 1643 s, t, sym_name(policydb, SYM_CLASSES, tclass-1)); 1644 audit_log_end(ab); 1645 out: 1646 kfree(s); 1647 kfree(t); 1648 kfree(n); 1649 if (!enforcing_enabled(state)) 1650 return 0; 1651 return -EACCES; 1652 } 1653 1654 static void filename_compute_type(struct policydb *policydb, 1655 struct context *newcontext, 1656 u32 stype, u32 ttype, u16 tclass, 1657 const char *objname) 1658 { 1659 struct filename_trans_key ft; 1660 struct filename_trans_datum *datum; 1661 1662 /* 1663 * Most filename trans rules are going to live in specific directories 1664 * like /dev or /var/run. This bitmap will quickly skip rule searches 1665 * if the ttype does not contain any rules. 1666 */ 1667 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype)) 1668 return; 1669 1670 ft.ttype = ttype; 1671 ft.tclass = tclass; 1672 ft.name = objname; 1673 1674 datum = policydb_filenametr_search(policydb, &ft); 1675 while (datum) { 1676 if (ebitmap_get_bit(&datum->stypes, stype - 1)) { 1677 newcontext->type = datum->otype; 1678 return; 1679 } 1680 datum = datum->next; 1681 } 1682 } 1683 1684 static int security_compute_sid(struct selinux_state *state, 1685 u32 ssid, 1686 u32 tsid, 1687 u16 orig_tclass, 1688 u32 specified, 1689 const char *objname, 1690 u32 *out_sid, 1691 bool kern) 1692 { 1693 struct policydb *policydb; 1694 struct sidtab *sidtab; 1695 struct class_datum *cladatum = NULL; 1696 struct context *scontext, *tcontext, newcontext; 1697 struct sidtab_entry *sentry, *tentry; 1698 struct avtab_key avkey; 1699 struct avtab_datum *avdatum; 1700 struct avtab_node *node; 1701 u16 tclass; 1702 int rc = 0; 1703 bool sock; 1704 1705 if (!selinux_initialized(state)) { 1706 switch (orig_tclass) { 1707 case SECCLASS_PROCESS: /* kernel value */ 1708 *out_sid = ssid; 1709 break; 1710 default: 1711 *out_sid = tsid; 1712 break; 1713 } 1714 goto out; 1715 } 1716 1717 context_init(&newcontext); 1718 1719 read_lock(&state->ss->policy_rwlock); 1720 1721 if (kern) { 1722 tclass = unmap_class(&state->ss->map, orig_tclass); 1723 sock = security_is_socket_class(orig_tclass); 1724 } else { 1725 tclass = orig_tclass; 1726 sock = security_is_socket_class(map_class(&state->ss->map, 1727 tclass)); 1728 } 1729 1730 policydb = &state->ss->policydb; 1731 sidtab = state->ss->sidtab; 1732 1733 sentry = sidtab_search_entry(sidtab, ssid); 1734 if (!sentry) { 1735 pr_err("SELinux: %s: unrecognized SID %d\n", 1736 __func__, ssid); 1737 rc = -EINVAL; 1738 goto out_unlock; 1739 } 1740 tentry = sidtab_search_entry(sidtab, tsid); 1741 if (!tentry) { 1742 pr_err("SELinux: %s: unrecognized SID %d\n", 1743 __func__, tsid); 1744 rc = -EINVAL; 1745 goto out_unlock; 1746 } 1747 1748 scontext = &sentry->context; 1749 tcontext = &tentry->context; 1750 1751 if (tclass && tclass <= policydb->p_classes.nprim) 1752 cladatum = policydb->class_val_to_struct[tclass - 1]; 1753 1754 /* Set the user identity. */ 1755 switch (specified) { 1756 case AVTAB_TRANSITION: 1757 case AVTAB_CHANGE: 1758 if (cladatum && cladatum->default_user == DEFAULT_TARGET) { 1759 newcontext.user = tcontext->user; 1760 } else { 1761 /* notice this gets both DEFAULT_SOURCE and unset */ 1762 /* Use the process user identity. */ 1763 newcontext.user = scontext->user; 1764 } 1765 break; 1766 case AVTAB_MEMBER: 1767 /* Use the related object owner. */ 1768 newcontext.user = tcontext->user; 1769 break; 1770 } 1771 1772 /* Set the role to default values. */ 1773 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) { 1774 newcontext.role = scontext->role; 1775 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { 1776 newcontext.role = tcontext->role; 1777 } else { 1778 if ((tclass == policydb->process_class) || sock) 1779 newcontext.role = scontext->role; 1780 else 1781 newcontext.role = OBJECT_R_VAL; 1782 } 1783 1784 /* Set the type to default values. */ 1785 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) { 1786 newcontext.type = scontext->type; 1787 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { 1788 newcontext.type = tcontext->type; 1789 } else { 1790 if ((tclass == policydb->process_class) || sock) { 1791 /* Use the type of process. */ 1792 newcontext.type = scontext->type; 1793 } else { 1794 /* Use the type of the related object. */ 1795 newcontext.type = tcontext->type; 1796 } 1797 } 1798 1799 /* Look for a type transition/member/change rule. */ 1800 avkey.source_type = scontext->type; 1801 avkey.target_type = tcontext->type; 1802 avkey.target_class = tclass; 1803 avkey.specified = specified; 1804 avdatum = avtab_search(&policydb->te_avtab, &avkey); 1805 1806 /* If no permanent rule, also check for enabled conditional rules */ 1807 if (!avdatum) { 1808 node = avtab_search_node(&policydb->te_cond_avtab, &avkey); 1809 for (; node; node = avtab_search_node_next(node, specified)) { 1810 if (node->key.specified & AVTAB_ENABLED) { 1811 avdatum = &node->datum; 1812 break; 1813 } 1814 } 1815 } 1816 1817 if (avdatum) { 1818 /* Use the type from the type transition/member/change rule. */ 1819 newcontext.type = avdatum->u.data; 1820 } 1821 1822 /* if we have a objname this is a file trans check so check those rules */ 1823 if (objname) 1824 filename_compute_type(policydb, &newcontext, scontext->type, 1825 tcontext->type, tclass, objname); 1826 1827 /* Check for class-specific changes. */ 1828 if (specified & AVTAB_TRANSITION) { 1829 /* Look for a role transition rule. */ 1830 struct role_trans_datum *rtd; 1831 struct role_trans_key rtk = { 1832 .role = scontext->role, 1833 .type = tcontext->type, 1834 .tclass = tclass, 1835 }; 1836 1837 rtd = policydb_roletr_search(policydb, &rtk); 1838 if (rtd) 1839 newcontext.role = rtd->new_role; 1840 } 1841 1842 /* Set the MLS attributes. 1843 This is done last because it may allocate memory. */ 1844 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified, 1845 &newcontext, sock); 1846 if (rc) 1847 goto out_unlock; 1848 1849 /* Check the validity of the context. */ 1850 if (!policydb_context_isvalid(policydb, &newcontext)) { 1851 rc = compute_sid_handle_invalid_context(state, sentry, tentry, 1852 tclass, &newcontext); 1853 if (rc) 1854 goto out_unlock; 1855 } 1856 /* Obtain the sid for the context. */ 1857 rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid); 1858 out_unlock: 1859 read_unlock(&state->ss->policy_rwlock); 1860 context_destroy(&newcontext); 1861 out: 1862 return rc; 1863 } 1864 1865 /** 1866 * security_transition_sid - Compute the SID for a new subject/object. 1867 * @ssid: source security identifier 1868 * @tsid: target security identifier 1869 * @tclass: target security class 1870 * @out_sid: security identifier for new subject/object 1871 * 1872 * Compute a SID to use for labeling a new subject or object in the 1873 * class @tclass 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 new SID was 1876 * computed successfully. 1877 */ 1878 int security_transition_sid(struct selinux_state *state, 1879 u32 ssid, u32 tsid, u16 tclass, 1880 const struct qstr *qstr, u32 *out_sid) 1881 { 1882 return security_compute_sid(state, ssid, tsid, tclass, 1883 AVTAB_TRANSITION, 1884 qstr ? qstr->name : NULL, out_sid, true); 1885 } 1886 1887 int security_transition_sid_user(struct selinux_state *state, 1888 u32 ssid, u32 tsid, u16 tclass, 1889 const char *objname, u32 *out_sid) 1890 { 1891 return security_compute_sid(state, ssid, tsid, tclass, 1892 AVTAB_TRANSITION, 1893 objname, out_sid, false); 1894 } 1895 1896 /** 1897 * security_member_sid - Compute the SID for member selection. 1898 * @ssid: source security identifier 1899 * @tsid: target security identifier 1900 * @tclass: target security class 1901 * @out_sid: security identifier for selected member 1902 * 1903 * Compute a SID to use when selecting a member of a polyinstantiated 1904 * object of class @tclass based on a SID pair (@ssid, @tsid). 1905 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1906 * if insufficient memory is available, or %0 if the SID was 1907 * computed successfully. 1908 */ 1909 int security_member_sid(struct selinux_state *state, 1910 u32 ssid, 1911 u32 tsid, 1912 u16 tclass, 1913 u32 *out_sid) 1914 { 1915 return security_compute_sid(state, ssid, tsid, tclass, 1916 AVTAB_MEMBER, NULL, 1917 out_sid, false); 1918 } 1919 1920 /** 1921 * security_change_sid - Compute the SID for object relabeling. 1922 * @ssid: source security identifier 1923 * @tsid: target security identifier 1924 * @tclass: target security class 1925 * @out_sid: security identifier for selected member 1926 * 1927 * Compute a SID to use for relabeling an object of class @tclass 1928 * based on a SID pair (@ssid, @tsid). 1929 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1930 * if insufficient memory is available, or %0 if the SID was 1931 * computed successfully. 1932 */ 1933 int security_change_sid(struct selinux_state *state, 1934 u32 ssid, 1935 u32 tsid, 1936 u16 tclass, 1937 u32 *out_sid) 1938 { 1939 return security_compute_sid(state, 1940 ssid, tsid, tclass, AVTAB_CHANGE, NULL, 1941 out_sid, false); 1942 } 1943 1944 static inline int convert_context_handle_invalid_context( 1945 struct selinux_state *state, 1946 struct context *context) 1947 { 1948 struct policydb *policydb = &state->ss->policydb; 1949 char *s; 1950 u32 len; 1951 1952 if (enforcing_enabled(state)) 1953 return -EINVAL; 1954 1955 if (!context_struct_to_string(policydb, context, &s, &len)) { 1956 pr_warn("SELinux: Context %s would be invalid if enforcing\n", 1957 s); 1958 kfree(s); 1959 } 1960 return 0; 1961 } 1962 1963 struct convert_context_args { 1964 struct selinux_state *state; 1965 struct policydb *oldp; 1966 struct policydb *newp; 1967 }; 1968 1969 /* 1970 * Convert the values in the security context 1971 * structure `oldc' from the values specified 1972 * in the policy `p->oldp' to the values specified 1973 * in the policy `p->newp', storing the new context 1974 * in `newc'. Verify that the context is valid 1975 * under the new policy. 1976 */ 1977 static int convert_context(struct context *oldc, struct context *newc, void *p) 1978 { 1979 struct convert_context_args *args; 1980 struct ocontext *oc; 1981 struct role_datum *role; 1982 struct type_datum *typdatum; 1983 struct user_datum *usrdatum; 1984 char *s; 1985 u32 len; 1986 int rc; 1987 1988 args = p; 1989 1990 if (oldc->str) { 1991 s = kstrdup(oldc->str, GFP_KERNEL); 1992 if (!s) 1993 return -ENOMEM; 1994 1995 rc = string_to_context_struct(args->newp, NULL, s, 1996 newc, SECSID_NULL); 1997 if (rc == -EINVAL) { 1998 /* 1999 * Retain string representation for later mapping. 2000 * 2001 * IMPORTANT: We need to copy the contents of oldc->str 2002 * back into s again because string_to_context_struct() 2003 * may have garbled it. 2004 */ 2005 memcpy(s, oldc->str, oldc->len); 2006 context_init(newc); 2007 newc->str = s; 2008 newc->len = oldc->len; 2009 return 0; 2010 } 2011 kfree(s); 2012 if (rc) { 2013 /* Other error condition, e.g. ENOMEM. */ 2014 pr_err("SELinux: Unable to map context %s, rc = %d.\n", 2015 oldc->str, -rc); 2016 return rc; 2017 } 2018 pr_info("SELinux: Context %s became valid (mapped).\n", 2019 oldc->str); 2020 return 0; 2021 } 2022 2023 context_init(newc); 2024 2025 /* Convert the user. */ 2026 rc = -EINVAL; 2027 usrdatum = symtab_search(&args->newp->p_users, 2028 sym_name(args->oldp, 2029 SYM_USERS, oldc->user - 1)); 2030 if (!usrdatum) 2031 goto bad; 2032 newc->user = usrdatum->value; 2033 2034 /* Convert the role. */ 2035 rc = -EINVAL; 2036 role = symtab_search(&args->newp->p_roles, 2037 sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); 2038 if (!role) 2039 goto bad; 2040 newc->role = role->value; 2041 2042 /* Convert the type. */ 2043 rc = -EINVAL; 2044 typdatum = symtab_search(&args->newp->p_types, 2045 sym_name(args->oldp, 2046 SYM_TYPES, oldc->type - 1)); 2047 if (!typdatum) 2048 goto bad; 2049 newc->type = typdatum->value; 2050 2051 /* Convert the MLS fields if dealing with MLS policies */ 2052 if (args->oldp->mls_enabled && args->newp->mls_enabled) { 2053 rc = mls_convert_context(args->oldp, args->newp, oldc, newc); 2054 if (rc) 2055 goto bad; 2056 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { 2057 /* 2058 * Switching between non-MLS and MLS policy: 2059 * ensure that the MLS fields of the context for all 2060 * existing entries in the sidtab are filled in with a 2061 * suitable default value, likely taken from one of the 2062 * initial SIDs. 2063 */ 2064 oc = args->newp->ocontexts[OCON_ISID]; 2065 while (oc && oc->sid[0] != SECINITSID_UNLABELED) 2066 oc = oc->next; 2067 rc = -EINVAL; 2068 if (!oc) { 2069 pr_err("SELinux: unable to look up" 2070 " the initial SIDs list\n"); 2071 goto bad; 2072 } 2073 rc = mls_range_set(newc, &oc->context[0].range); 2074 if (rc) 2075 goto bad; 2076 } 2077 2078 /* Check the validity of the new context. */ 2079 if (!policydb_context_isvalid(args->newp, newc)) { 2080 rc = convert_context_handle_invalid_context(args->state, oldc); 2081 if (rc) 2082 goto bad; 2083 } 2084 2085 return 0; 2086 bad: 2087 /* Map old representation to string and save it. */ 2088 rc = context_struct_to_string(args->oldp, oldc, &s, &len); 2089 if (rc) 2090 return rc; 2091 context_destroy(newc); 2092 newc->str = s; 2093 newc->len = len; 2094 pr_info("SELinux: Context %s became invalid (unmapped).\n", 2095 newc->str); 2096 return 0; 2097 } 2098 2099 static void security_load_policycaps(struct selinux_state *state) 2100 { 2101 struct policydb *p = &state->ss->policydb; 2102 unsigned int i; 2103 struct ebitmap_node *node; 2104 2105 for (i = 0; i < ARRAY_SIZE(state->policycap); i++) 2106 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i); 2107 2108 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) 2109 pr_info("SELinux: policy capability %s=%d\n", 2110 selinux_policycap_names[i], 2111 ebitmap_get_bit(&p->policycaps, i)); 2112 2113 ebitmap_for_each_positive_bit(&p->policycaps, node, i) { 2114 if (i >= ARRAY_SIZE(selinux_policycap_names)) 2115 pr_info("SELinux: unknown policy capability %u\n", 2116 i); 2117 } 2118 } 2119 2120 static int security_preserve_bools(struct selinux_state *state, 2121 struct policydb *newpolicydb); 2122 2123 /** 2124 * security_load_policy - Load a security policy configuration. 2125 * @data: binary policy data 2126 * @len: length of data in bytes 2127 * 2128 * Load a new set of security policy configuration data, 2129 * validate it and convert the SID table as necessary. 2130 * This function will flush the access vector cache after 2131 * loading the new policy. 2132 */ 2133 int security_load_policy(struct selinux_state *state, void *data, size_t len) 2134 { 2135 struct policydb *policydb; 2136 struct sidtab *oldsidtab, *newsidtab; 2137 struct policydb *oldpolicydb, *newpolicydb; 2138 struct selinux_mapping *oldmapping; 2139 struct selinux_map newmap; 2140 struct sidtab_convert_params convert_params; 2141 struct convert_context_args args; 2142 u32 seqno; 2143 int rc = 0; 2144 struct policy_file file = { data, len }, *fp = &file; 2145 2146 policydb = &state->ss->policydb; 2147 2148 newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL); 2149 if (!newsidtab) 2150 return -ENOMEM; 2151 2152 if (!selinux_initialized(state)) { 2153 rc = policydb_read(policydb, fp); 2154 if (rc) { 2155 kfree(newsidtab); 2156 return rc; 2157 } 2158 2159 policydb->len = len; 2160 rc = selinux_set_mapping(policydb, secclass_map, 2161 &state->ss->map); 2162 if (rc) { 2163 kfree(newsidtab); 2164 policydb_destroy(policydb); 2165 return rc; 2166 } 2167 2168 rc = policydb_load_isids(policydb, newsidtab); 2169 if (rc) { 2170 kfree(newsidtab); 2171 policydb_destroy(policydb); 2172 return rc; 2173 } 2174 2175 state->ss->sidtab = newsidtab; 2176 security_load_policycaps(state); 2177 selinux_mark_initialized(state); 2178 seqno = ++state->ss->latest_granting; 2179 selinux_complete_init(); 2180 avc_ss_reset(state->avc, seqno); 2181 selnl_notify_policyload(seqno); 2182 selinux_status_update_policyload(state, seqno); 2183 selinux_netlbl_cache_invalidate(); 2184 selinux_xfrm_notify_policyload(); 2185 return 0; 2186 } 2187 2188 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL); 2189 if (!oldpolicydb) { 2190 kfree(newsidtab); 2191 return -ENOMEM; 2192 } 2193 newpolicydb = oldpolicydb + 1; 2194 2195 rc = policydb_read(newpolicydb, fp); 2196 if (rc) { 2197 kfree(newsidtab); 2198 goto out; 2199 } 2200 2201 newpolicydb->len = len; 2202 /* If switching between different policy types, log MLS status */ 2203 if (policydb->mls_enabled && !newpolicydb->mls_enabled) 2204 pr_info("SELinux: Disabling MLS support...\n"); 2205 else if (!policydb->mls_enabled && newpolicydb->mls_enabled) 2206 pr_info("SELinux: Enabling MLS support...\n"); 2207 2208 rc = policydb_load_isids(newpolicydb, newsidtab); 2209 if (rc) { 2210 pr_err("SELinux: unable to load the initial SIDs\n"); 2211 policydb_destroy(newpolicydb); 2212 kfree(newsidtab); 2213 goto out; 2214 } 2215 2216 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap); 2217 if (rc) 2218 goto err; 2219 2220 rc = security_preserve_bools(state, newpolicydb); 2221 if (rc) { 2222 pr_err("SELinux: unable to preserve booleans\n"); 2223 goto err; 2224 } 2225 2226 oldsidtab = state->ss->sidtab; 2227 2228 /* 2229 * Convert the internal representations of contexts 2230 * in the new SID table. 2231 */ 2232 args.state = state; 2233 args.oldp = policydb; 2234 args.newp = newpolicydb; 2235 2236 convert_params.func = convert_context; 2237 convert_params.args = &args; 2238 convert_params.target = newsidtab; 2239 2240 rc = sidtab_convert(oldsidtab, &convert_params); 2241 if (rc) { 2242 pr_err("SELinux: unable to convert the internal" 2243 " representation of contexts in the new SID" 2244 " table\n"); 2245 goto err; 2246 } 2247 2248 /* Save the old policydb and SID table to free later. */ 2249 memcpy(oldpolicydb, policydb, sizeof(*policydb)); 2250 2251 /* Install the new policydb and SID table. */ 2252 write_lock_irq(&state->ss->policy_rwlock); 2253 memcpy(policydb, newpolicydb, sizeof(*policydb)); 2254 state->ss->sidtab = newsidtab; 2255 security_load_policycaps(state); 2256 oldmapping = state->ss->map.mapping; 2257 state->ss->map.mapping = newmap.mapping; 2258 state->ss->map.size = newmap.size; 2259 seqno = ++state->ss->latest_granting; 2260 write_unlock_irq(&state->ss->policy_rwlock); 2261 2262 /* Free the old policydb and SID table. */ 2263 policydb_destroy(oldpolicydb); 2264 sidtab_destroy(oldsidtab); 2265 kfree(oldsidtab); 2266 kfree(oldmapping); 2267 2268 avc_ss_reset(state->avc, seqno); 2269 selnl_notify_policyload(seqno); 2270 selinux_status_update_policyload(state, seqno); 2271 selinux_netlbl_cache_invalidate(); 2272 selinux_xfrm_notify_policyload(); 2273 2274 rc = 0; 2275 goto out; 2276 2277 err: 2278 kfree(newmap.mapping); 2279 sidtab_destroy(newsidtab); 2280 kfree(newsidtab); 2281 policydb_destroy(newpolicydb); 2282 2283 out: 2284 kfree(oldpolicydb); 2285 return rc; 2286 } 2287 2288 size_t security_policydb_len(struct selinux_state *state) 2289 { 2290 struct policydb *p = &state->ss->policydb; 2291 size_t len; 2292 2293 read_lock(&state->ss->policy_rwlock); 2294 len = p->len; 2295 read_unlock(&state->ss->policy_rwlock); 2296 2297 return len; 2298 } 2299 2300 /** 2301 * security_port_sid - Obtain the SID for a port. 2302 * @protocol: protocol number 2303 * @port: port number 2304 * @out_sid: security identifier 2305 */ 2306 int security_port_sid(struct selinux_state *state, 2307 u8 protocol, u16 port, u32 *out_sid) 2308 { 2309 struct policydb *policydb; 2310 struct sidtab *sidtab; 2311 struct ocontext *c; 2312 int rc = 0; 2313 2314 read_lock(&state->ss->policy_rwlock); 2315 2316 policydb = &state->ss->policydb; 2317 sidtab = state->ss->sidtab; 2318 2319 c = policydb->ocontexts[OCON_PORT]; 2320 while (c) { 2321 if (c->u.port.protocol == protocol && 2322 c->u.port.low_port <= port && 2323 c->u.port.high_port >= port) 2324 break; 2325 c = c->next; 2326 } 2327 2328 if (c) { 2329 if (!c->sid[0]) { 2330 rc = sidtab_context_to_sid(sidtab, &c->context[0], 2331 &c->sid[0]); 2332 if (rc) 2333 goto out; 2334 } 2335 *out_sid = c->sid[0]; 2336 } else { 2337 *out_sid = SECINITSID_PORT; 2338 } 2339 2340 out: 2341 read_unlock(&state->ss->policy_rwlock); 2342 return rc; 2343 } 2344 2345 /** 2346 * security_pkey_sid - Obtain the SID for a pkey. 2347 * @subnet_prefix: Subnet Prefix 2348 * @pkey_num: pkey number 2349 * @out_sid: security identifier 2350 */ 2351 int security_ib_pkey_sid(struct selinux_state *state, 2352 u64 subnet_prefix, u16 pkey_num, u32 *out_sid) 2353 { 2354 struct policydb *policydb; 2355 struct sidtab *sidtab; 2356 struct ocontext *c; 2357 int rc = 0; 2358 2359 read_lock(&state->ss->policy_rwlock); 2360 2361 policydb = &state->ss->policydb; 2362 sidtab = state->ss->sidtab; 2363 2364 c = policydb->ocontexts[OCON_IBPKEY]; 2365 while (c) { 2366 if (c->u.ibpkey.low_pkey <= pkey_num && 2367 c->u.ibpkey.high_pkey >= pkey_num && 2368 c->u.ibpkey.subnet_prefix == subnet_prefix) 2369 break; 2370 2371 c = c->next; 2372 } 2373 2374 if (c) { 2375 if (!c->sid[0]) { 2376 rc = sidtab_context_to_sid(sidtab, 2377 &c->context[0], 2378 &c->sid[0]); 2379 if (rc) 2380 goto out; 2381 } 2382 *out_sid = c->sid[0]; 2383 } else 2384 *out_sid = SECINITSID_UNLABELED; 2385 2386 out: 2387 read_unlock(&state->ss->policy_rwlock); 2388 return rc; 2389 } 2390 2391 /** 2392 * security_ib_endport_sid - Obtain the SID for a subnet management interface. 2393 * @dev_name: device name 2394 * @port: port number 2395 * @out_sid: security identifier 2396 */ 2397 int security_ib_endport_sid(struct selinux_state *state, 2398 const char *dev_name, u8 port_num, u32 *out_sid) 2399 { 2400 struct policydb *policydb; 2401 struct sidtab *sidtab; 2402 struct ocontext *c; 2403 int rc = 0; 2404 2405 read_lock(&state->ss->policy_rwlock); 2406 2407 policydb = &state->ss->policydb; 2408 sidtab = state->ss->sidtab; 2409 2410 c = policydb->ocontexts[OCON_IBENDPORT]; 2411 while (c) { 2412 if (c->u.ibendport.port == port_num && 2413 !strncmp(c->u.ibendport.dev_name, 2414 dev_name, 2415 IB_DEVICE_NAME_MAX)) 2416 break; 2417 2418 c = c->next; 2419 } 2420 2421 if (c) { 2422 if (!c->sid[0]) { 2423 rc = sidtab_context_to_sid(sidtab, &c->context[0], 2424 &c->sid[0]); 2425 if (rc) 2426 goto out; 2427 } 2428 *out_sid = c->sid[0]; 2429 } else 2430 *out_sid = SECINITSID_UNLABELED; 2431 2432 out: 2433 read_unlock(&state->ss->policy_rwlock); 2434 return rc; 2435 } 2436 2437 /** 2438 * security_netif_sid - Obtain the SID for a network interface. 2439 * @name: interface name 2440 * @if_sid: interface SID 2441 */ 2442 int security_netif_sid(struct selinux_state *state, 2443 char *name, u32 *if_sid) 2444 { 2445 struct policydb *policydb; 2446 struct sidtab *sidtab; 2447 int rc = 0; 2448 struct ocontext *c; 2449 2450 read_lock(&state->ss->policy_rwlock); 2451 2452 policydb = &state->ss->policydb; 2453 sidtab = state->ss->sidtab; 2454 2455 c = policydb->ocontexts[OCON_NETIF]; 2456 while (c) { 2457 if (strcmp(name, c->u.name) == 0) 2458 break; 2459 c = c->next; 2460 } 2461 2462 if (c) { 2463 if (!c->sid[0] || !c->sid[1]) { 2464 rc = sidtab_context_to_sid(sidtab, &c->context[0], 2465 &c->sid[0]); 2466 if (rc) 2467 goto out; 2468 rc = sidtab_context_to_sid(sidtab, &c->context[1], 2469 &c->sid[1]); 2470 if (rc) 2471 goto out; 2472 } 2473 *if_sid = c->sid[0]; 2474 } else 2475 *if_sid = SECINITSID_NETIF; 2476 2477 out: 2478 read_unlock(&state->ss->policy_rwlock); 2479 return rc; 2480 } 2481 2482 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) 2483 { 2484 int i, fail = 0; 2485 2486 for (i = 0; i < 4; i++) 2487 if (addr[i] != (input[i] & mask[i])) { 2488 fail = 1; 2489 break; 2490 } 2491 2492 return !fail; 2493 } 2494 2495 /** 2496 * security_node_sid - Obtain the SID for a node (host). 2497 * @domain: communication domain aka address family 2498 * @addrp: address 2499 * @addrlen: address length in bytes 2500 * @out_sid: security identifier 2501 */ 2502 int security_node_sid(struct selinux_state *state, 2503 u16 domain, 2504 void *addrp, 2505 u32 addrlen, 2506 u32 *out_sid) 2507 { 2508 struct policydb *policydb; 2509 struct sidtab *sidtab; 2510 int rc; 2511 struct ocontext *c; 2512 2513 read_lock(&state->ss->policy_rwlock); 2514 2515 policydb = &state->ss->policydb; 2516 sidtab = state->ss->sidtab; 2517 2518 switch (domain) { 2519 case AF_INET: { 2520 u32 addr; 2521 2522 rc = -EINVAL; 2523 if (addrlen != sizeof(u32)) 2524 goto out; 2525 2526 addr = *((u32 *)addrp); 2527 2528 c = policydb->ocontexts[OCON_NODE]; 2529 while (c) { 2530 if (c->u.node.addr == (addr & c->u.node.mask)) 2531 break; 2532 c = c->next; 2533 } 2534 break; 2535 } 2536 2537 case AF_INET6: 2538 rc = -EINVAL; 2539 if (addrlen != sizeof(u64) * 2) 2540 goto out; 2541 c = policydb->ocontexts[OCON_NODE6]; 2542 while (c) { 2543 if (match_ipv6_addrmask(addrp, c->u.node6.addr, 2544 c->u.node6.mask)) 2545 break; 2546 c = c->next; 2547 } 2548 break; 2549 2550 default: 2551 rc = 0; 2552 *out_sid = SECINITSID_NODE; 2553 goto out; 2554 } 2555 2556 if (c) { 2557 if (!c->sid[0]) { 2558 rc = sidtab_context_to_sid(sidtab, 2559 &c->context[0], 2560 &c->sid[0]); 2561 if (rc) 2562 goto out; 2563 } 2564 *out_sid = c->sid[0]; 2565 } else { 2566 *out_sid = SECINITSID_NODE; 2567 } 2568 2569 rc = 0; 2570 out: 2571 read_unlock(&state->ss->policy_rwlock); 2572 return rc; 2573 } 2574 2575 #define SIDS_NEL 25 2576 2577 /** 2578 * security_get_user_sids - Obtain reachable SIDs for a user. 2579 * @fromsid: starting SID 2580 * @username: username 2581 * @sids: array of reachable SIDs for user 2582 * @nel: number of elements in @sids 2583 * 2584 * Generate the set of SIDs for legal security contexts 2585 * for a given user that can be reached by @fromsid. 2586 * Set *@sids to point to a dynamically allocated 2587 * array containing the set of SIDs. Set *@nel to the 2588 * number of elements in the array. 2589 */ 2590 2591 int security_get_user_sids(struct selinux_state *state, 2592 u32 fromsid, 2593 char *username, 2594 u32 **sids, 2595 u32 *nel) 2596 { 2597 struct policydb *policydb; 2598 struct sidtab *sidtab; 2599 struct context *fromcon, usercon; 2600 u32 *mysids = NULL, *mysids2, sid; 2601 u32 mynel = 0, maxnel = SIDS_NEL; 2602 struct user_datum *user; 2603 struct role_datum *role; 2604 struct ebitmap_node *rnode, *tnode; 2605 int rc = 0, i, j; 2606 2607 *sids = NULL; 2608 *nel = 0; 2609 2610 if (!selinux_initialized(state)) 2611 goto out; 2612 2613 read_lock(&state->ss->policy_rwlock); 2614 2615 policydb = &state->ss->policydb; 2616 sidtab = state->ss->sidtab; 2617 2618 context_init(&usercon); 2619 2620 rc = -EINVAL; 2621 fromcon = sidtab_search(sidtab, fromsid); 2622 if (!fromcon) 2623 goto out_unlock; 2624 2625 rc = -EINVAL; 2626 user = symtab_search(&policydb->p_users, username); 2627 if (!user) 2628 goto out_unlock; 2629 2630 usercon.user = user->value; 2631 2632 rc = -ENOMEM; 2633 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); 2634 if (!mysids) 2635 goto out_unlock; 2636 2637 ebitmap_for_each_positive_bit(&user->roles, rnode, i) { 2638 role = policydb->role_val_to_struct[i]; 2639 usercon.role = i + 1; 2640 ebitmap_for_each_positive_bit(&role->types, tnode, j) { 2641 usercon.type = j + 1; 2642 2643 if (mls_setup_user_range(policydb, fromcon, user, 2644 &usercon)) 2645 continue; 2646 2647 rc = sidtab_context_to_sid(sidtab, &usercon, &sid); 2648 if (rc) 2649 goto out_unlock; 2650 if (mynel < maxnel) { 2651 mysids[mynel++] = sid; 2652 } else { 2653 rc = -ENOMEM; 2654 maxnel += SIDS_NEL; 2655 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); 2656 if (!mysids2) 2657 goto out_unlock; 2658 memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); 2659 kfree(mysids); 2660 mysids = mysids2; 2661 mysids[mynel++] = sid; 2662 } 2663 } 2664 } 2665 rc = 0; 2666 out_unlock: 2667 read_unlock(&state->ss->policy_rwlock); 2668 if (rc || !mynel) { 2669 kfree(mysids); 2670 goto out; 2671 } 2672 2673 rc = -ENOMEM; 2674 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); 2675 if (!mysids2) { 2676 kfree(mysids); 2677 goto out; 2678 } 2679 for (i = 0, j = 0; i < mynel; i++) { 2680 struct av_decision dummy_avd; 2681 rc = avc_has_perm_noaudit(state, 2682 fromsid, mysids[i], 2683 SECCLASS_PROCESS, /* kernel value */ 2684 PROCESS__TRANSITION, AVC_STRICT, 2685 &dummy_avd); 2686 if (!rc) 2687 mysids2[j++] = mysids[i]; 2688 cond_resched(); 2689 } 2690 rc = 0; 2691 kfree(mysids); 2692 *sids = mysids2; 2693 *nel = j; 2694 out: 2695 return rc; 2696 } 2697 2698 /** 2699 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem 2700 * @fstype: filesystem type 2701 * @path: path from root of mount 2702 * @sclass: file security class 2703 * @sid: SID for path 2704 * 2705 * Obtain a SID to use for a file in a filesystem that 2706 * cannot support xattr or use a fixed labeling behavior like 2707 * transition SIDs or task SIDs. 2708 * 2709 * The caller must acquire the policy_rwlock before calling this function. 2710 */ 2711 static inline int __security_genfs_sid(struct selinux_state *state, 2712 const char *fstype, 2713 char *path, 2714 u16 orig_sclass, 2715 u32 *sid) 2716 { 2717 struct policydb *policydb = &state->ss->policydb; 2718 struct sidtab *sidtab = state->ss->sidtab; 2719 int len; 2720 u16 sclass; 2721 struct genfs *genfs; 2722 struct ocontext *c; 2723 int rc, cmp = 0; 2724 2725 while (path[0] == '/' && path[1] == '/') 2726 path++; 2727 2728 sclass = unmap_class(&state->ss->map, orig_sclass); 2729 *sid = SECINITSID_UNLABELED; 2730 2731 for (genfs = policydb->genfs; genfs; genfs = genfs->next) { 2732 cmp = strcmp(fstype, genfs->fstype); 2733 if (cmp <= 0) 2734 break; 2735 } 2736 2737 rc = -ENOENT; 2738 if (!genfs || cmp) 2739 goto out; 2740 2741 for (c = genfs->head; c; c = c->next) { 2742 len = strlen(c->u.name); 2743 if ((!c->v.sclass || sclass == c->v.sclass) && 2744 (strncmp(c->u.name, path, len) == 0)) 2745 break; 2746 } 2747 2748 rc = -ENOENT; 2749 if (!c) 2750 goto out; 2751 2752 if (!c->sid[0]) { 2753 rc = sidtab_context_to_sid(sidtab, &c->context[0], &c->sid[0]); 2754 if (rc) 2755 goto out; 2756 } 2757 2758 *sid = c->sid[0]; 2759 rc = 0; 2760 out: 2761 return rc; 2762 } 2763 2764 /** 2765 * security_genfs_sid - Obtain a SID for a file in a filesystem 2766 * @fstype: filesystem type 2767 * @path: path from root of mount 2768 * @sclass: file security class 2769 * @sid: SID for path 2770 * 2771 * Acquire policy_rwlock before calling __security_genfs_sid() and release 2772 * it afterward. 2773 */ 2774 int security_genfs_sid(struct selinux_state *state, 2775 const char *fstype, 2776 char *path, 2777 u16 orig_sclass, 2778 u32 *sid) 2779 { 2780 int retval; 2781 2782 read_lock(&state->ss->policy_rwlock); 2783 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid); 2784 read_unlock(&state->ss->policy_rwlock); 2785 return retval; 2786 } 2787 2788 /** 2789 * security_fs_use - Determine how to handle labeling for a filesystem. 2790 * @sb: superblock in question 2791 */ 2792 int security_fs_use(struct selinux_state *state, struct super_block *sb) 2793 { 2794 struct policydb *policydb; 2795 struct sidtab *sidtab; 2796 int rc = 0; 2797 struct ocontext *c; 2798 struct superblock_security_struct *sbsec = sb->s_security; 2799 const char *fstype = sb->s_type->name; 2800 2801 read_lock(&state->ss->policy_rwlock); 2802 2803 policydb = &state->ss->policydb; 2804 sidtab = state->ss->sidtab; 2805 2806 c = policydb->ocontexts[OCON_FSUSE]; 2807 while (c) { 2808 if (strcmp(fstype, c->u.name) == 0) 2809 break; 2810 c = c->next; 2811 } 2812 2813 if (c) { 2814 sbsec->behavior = c->v.behavior; 2815 if (!c->sid[0]) { 2816 rc = sidtab_context_to_sid(sidtab, &c->context[0], 2817 &c->sid[0]); 2818 if (rc) 2819 goto out; 2820 } 2821 sbsec->sid = c->sid[0]; 2822 } else { 2823 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR, 2824 &sbsec->sid); 2825 if (rc) { 2826 sbsec->behavior = SECURITY_FS_USE_NONE; 2827 rc = 0; 2828 } else { 2829 sbsec->behavior = SECURITY_FS_USE_GENFS; 2830 } 2831 } 2832 2833 out: 2834 read_unlock(&state->ss->policy_rwlock); 2835 return rc; 2836 } 2837 2838 int security_get_bools(struct selinux_state *state, 2839 u32 *len, char ***names, int **values) 2840 { 2841 struct policydb *policydb; 2842 u32 i; 2843 int rc; 2844 2845 if (!selinux_initialized(state)) { 2846 *len = 0; 2847 *names = NULL; 2848 *values = NULL; 2849 return 0; 2850 } 2851 2852 read_lock(&state->ss->policy_rwlock); 2853 2854 policydb = &state->ss->policydb; 2855 2856 *names = NULL; 2857 *values = NULL; 2858 2859 rc = 0; 2860 *len = policydb->p_bools.nprim; 2861 if (!*len) 2862 goto out; 2863 2864 rc = -ENOMEM; 2865 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); 2866 if (!*names) 2867 goto err; 2868 2869 rc = -ENOMEM; 2870 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); 2871 if (!*values) 2872 goto err; 2873 2874 for (i = 0; i < *len; i++) { 2875 (*values)[i] = policydb->bool_val_to_struct[i]->state; 2876 2877 rc = -ENOMEM; 2878 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i), 2879 GFP_ATOMIC); 2880 if (!(*names)[i]) 2881 goto err; 2882 } 2883 rc = 0; 2884 out: 2885 read_unlock(&state->ss->policy_rwlock); 2886 return rc; 2887 err: 2888 if (*names) { 2889 for (i = 0; i < *len; i++) 2890 kfree((*names)[i]); 2891 kfree(*names); 2892 } 2893 kfree(*values); 2894 *len = 0; 2895 *names = NULL; 2896 *values = NULL; 2897 goto out; 2898 } 2899 2900 2901 int security_set_bools(struct selinux_state *state, u32 len, int *values) 2902 { 2903 struct policydb *policydb; 2904 int rc; 2905 u32 i, lenp, seqno = 0; 2906 2907 write_lock_irq(&state->ss->policy_rwlock); 2908 2909 policydb = &state->ss->policydb; 2910 2911 rc = -EFAULT; 2912 lenp = policydb->p_bools.nprim; 2913 if (len != lenp) 2914 goto out; 2915 2916 for (i = 0; i < len; i++) { 2917 if (!!values[i] != policydb->bool_val_to_struct[i]->state) { 2918 audit_log(audit_context(), GFP_ATOMIC, 2919 AUDIT_MAC_CONFIG_CHANGE, 2920 "bool=%s val=%d old_val=%d auid=%u ses=%u", 2921 sym_name(policydb, SYM_BOOLS, i), 2922 !!values[i], 2923 policydb->bool_val_to_struct[i]->state, 2924 from_kuid(&init_user_ns, audit_get_loginuid(current)), 2925 audit_get_sessionid(current)); 2926 } 2927 if (values[i]) 2928 policydb->bool_val_to_struct[i]->state = 1; 2929 else 2930 policydb->bool_val_to_struct[i]->state = 0; 2931 } 2932 2933 evaluate_cond_nodes(policydb); 2934 2935 seqno = ++state->ss->latest_granting; 2936 rc = 0; 2937 out: 2938 write_unlock_irq(&state->ss->policy_rwlock); 2939 if (!rc) { 2940 avc_ss_reset(state->avc, seqno); 2941 selnl_notify_policyload(seqno); 2942 selinux_status_update_policyload(state, seqno); 2943 selinux_xfrm_notify_policyload(); 2944 } 2945 return rc; 2946 } 2947 2948 int security_get_bool_value(struct selinux_state *state, 2949 u32 index) 2950 { 2951 struct policydb *policydb; 2952 int rc; 2953 u32 len; 2954 2955 read_lock(&state->ss->policy_rwlock); 2956 2957 policydb = &state->ss->policydb; 2958 2959 rc = -EFAULT; 2960 len = policydb->p_bools.nprim; 2961 if (index >= len) 2962 goto out; 2963 2964 rc = policydb->bool_val_to_struct[index]->state; 2965 out: 2966 read_unlock(&state->ss->policy_rwlock); 2967 return rc; 2968 } 2969 2970 static int security_preserve_bools(struct selinux_state *state, 2971 struct policydb *policydb) 2972 { 2973 int rc, *bvalues = NULL; 2974 char **bnames = NULL; 2975 struct cond_bool_datum *booldatum; 2976 u32 i, nbools = 0; 2977 2978 rc = security_get_bools(state, &nbools, &bnames, &bvalues); 2979 if (rc) 2980 goto out; 2981 for (i = 0; i < nbools; i++) { 2982 booldatum = symtab_search(&policydb->p_bools, bnames[i]); 2983 if (booldatum) 2984 booldatum->state = bvalues[i]; 2985 } 2986 evaluate_cond_nodes(policydb); 2987 2988 out: 2989 if (bnames) { 2990 for (i = 0; i < nbools; i++) 2991 kfree(bnames[i]); 2992 } 2993 kfree(bnames); 2994 kfree(bvalues); 2995 return rc; 2996 } 2997 2998 /* 2999 * security_sid_mls_copy() - computes a new sid based on the given 3000 * sid and the mls portion of mls_sid. 3001 */ 3002 int security_sid_mls_copy(struct selinux_state *state, 3003 u32 sid, u32 mls_sid, u32 *new_sid) 3004 { 3005 struct policydb *policydb = &state->ss->policydb; 3006 struct sidtab *sidtab = state->ss->sidtab; 3007 struct context *context1; 3008 struct context *context2; 3009 struct context newcon; 3010 char *s; 3011 u32 len; 3012 int rc; 3013 3014 rc = 0; 3015 if (!selinux_initialized(state) || !policydb->mls_enabled) { 3016 *new_sid = sid; 3017 goto out; 3018 } 3019 3020 context_init(&newcon); 3021 3022 read_lock(&state->ss->policy_rwlock); 3023 3024 rc = -EINVAL; 3025 context1 = sidtab_search(sidtab, sid); 3026 if (!context1) { 3027 pr_err("SELinux: %s: unrecognized SID %d\n", 3028 __func__, sid); 3029 goto out_unlock; 3030 } 3031 3032 rc = -EINVAL; 3033 context2 = sidtab_search(sidtab, mls_sid); 3034 if (!context2) { 3035 pr_err("SELinux: %s: unrecognized SID %d\n", 3036 __func__, mls_sid); 3037 goto out_unlock; 3038 } 3039 3040 newcon.user = context1->user; 3041 newcon.role = context1->role; 3042 newcon.type = context1->type; 3043 rc = mls_context_cpy(&newcon, context2); 3044 if (rc) 3045 goto out_unlock; 3046 3047 /* Check the validity of the new context. */ 3048 if (!policydb_context_isvalid(policydb, &newcon)) { 3049 rc = convert_context_handle_invalid_context(state, &newcon); 3050 if (rc) { 3051 if (!context_struct_to_string(policydb, &newcon, &s, 3052 &len)) { 3053 struct audit_buffer *ab; 3054 3055 ab = audit_log_start(audit_context(), 3056 GFP_ATOMIC, 3057 AUDIT_SELINUX_ERR); 3058 audit_log_format(ab, 3059 "op=security_sid_mls_copy invalid_context="); 3060 /* don't record NUL with untrusted strings */ 3061 audit_log_n_untrustedstring(ab, s, len - 1); 3062 audit_log_end(ab); 3063 kfree(s); 3064 } 3065 goto out_unlock; 3066 } 3067 } 3068 rc = sidtab_context_to_sid(sidtab, &newcon, new_sid); 3069 out_unlock: 3070 read_unlock(&state->ss->policy_rwlock); 3071 context_destroy(&newcon); 3072 out: 3073 return rc; 3074 } 3075 3076 /** 3077 * security_net_peersid_resolve - Compare and resolve two network peer SIDs 3078 * @nlbl_sid: NetLabel SID 3079 * @nlbl_type: NetLabel labeling protocol type 3080 * @xfrm_sid: XFRM SID 3081 * 3082 * Description: 3083 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be 3084 * resolved into a single SID it is returned via @peer_sid and the function 3085 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function 3086 * returns a negative value. A table summarizing the behavior is below: 3087 * 3088 * | function return | @sid 3089 * ------------------------------+-----------------+----------------- 3090 * no peer labels | 0 | SECSID_NULL 3091 * single peer label | 0 | <peer_label> 3092 * multiple, consistent labels | 0 | <peer_label> 3093 * multiple, inconsistent labels | -<errno> | SECSID_NULL 3094 * 3095 */ 3096 int security_net_peersid_resolve(struct selinux_state *state, 3097 u32 nlbl_sid, u32 nlbl_type, 3098 u32 xfrm_sid, 3099 u32 *peer_sid) 3100 { 3101 struct policydb *policydb = &state->ss->policydb; 3102 struct sidtab *sidtab = state->ss->sidtab; 3103 int rc; 3104 struct context *nlbl_ctx; 3105 struct context *xfrm_ctx; 3106 3107 *peer_sid = SECSID_NULL; 3108 3109 /* handle the common (which also happens to be the set of easy) cases 3110 * right away, these two if statements catch everything involving a 3111 * single or absent peer SID/label */ 3112 if (xfrm_sid == SECSID_NULL) { 3113 *peer_sid = nlbl_sid; 3114 return 0; 3115 } 3116 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label 3117 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label 3118 * is present */ 3119 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { 3120 *peer_sid = xfrm_sid; 3121 return 0; 3122 } 3123 3124 /* 3125 * We don't need to check initialized here since the only way both 3126 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the 3127 * security server was initialized and state->initialized was true. 3128 */ 3129 if (!policydb->mls_enabled) 3130 return 0; 3131 3132 read_lock(&state->ss->policy_rwlock); 3133 3134 rc = -EINVAL; 3135 nlbl_ctx = sidtab_search(sidtab, nlbl_sid); 3136 if (!nlbl_ctx) { 3137 pr_err("SELinux: %s: unrecognized SID %d\n", 3138 __func__, nlbl_sid); 3139 goto out; 3140 } 3141 rc = -EINVAL; 3142 xfrm_ctx = sidtab_search(sidtab, xfrm_sid); 3143 if (!xfrm_ctx) { 3144 pr_err("SELinux: %s: unrecognized SID %d\n", 3145 __func__, xfrm_sid); 3146 goto out; 3147 } 3148 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); 3149 if (rc) 3150 goto out; 3151 3152 /* at present NetLabel SIDs/labels really only carry MLS 3153 * information so if the MLS portion of the NetLabel SID 3154 * matches the MLS portion of the labeled XFRM SID/label 3155 * then pass along the XFRM SID as it is the most 3156 * expressive */ 3157 *peer_sid = xfrm_sid; 3158 out: 3159 read_unlock(&state->ss->policy_rwlock); 3160 return rc; 3161 } 3162 3163 static int get_classes_callback(void *k, void *d, void *args) 3164 { 3165 struct class_datum *datum = d; 3166 char *name = k, **classes = args; 3167 int value = datum->value - 1; 3168 3169 classes[value] = kstrdup(name, GFP_ATOMIC); 3170 if (!classes[value]) 3171 return -ENOMEM; 3172 3173 return 0; 3174 } 3175 3176 int security_get_classes(struct selinux_state *state, 3177 char ***classes, int *nclasses) 3178 { 3179 struct policydb *policydb = &state->ss->policydb; 3180 int rc; 3181 3182 if (!selinux_initialized(state)) { 3183 *nclasses = 0; 3184 *classes = NULL; 3185 return 0; 3186 } 3187 3188 read_lock(&state->ss->policy_rwlock); 3189 3190 rc = -ENOMEM; 3191 *nclasses = policydb->p_classes.nprim; 3192 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); 3193 if (!*classes) 3194 goto out; 3195 3196 rc = hashtab_map(&policydb->p_classes.table, get_classes_callback, 3197 *classes); 3198 if (rc) { 3199 int i; 3200 for (i = 0; i < *nclasses; i++) 3201 kfree((*classes)[i]); 3202 kfree(*classes); 3203 } 3204 3205 out: 3206 read_unlock(&state->ss->policy_rwlock); 3207 return rc; 3208 } 3209 3210 static int get_permissions_callback(void *k, void *d, void *args) 3211 { 3212 struct perm_datum *datum = d; 3213 char *name = k, **perms = args; 3214 int value = datum->value - 1; 3215 3216 perms[value] = kstrdup(name, GFP_ATOMIC); 3217 if (!perms[value]) 3218 return -ENOMEM; 3219 3220 return 0; 3221 } 3222 3223 int security_get_permissions(struct selinux_state *state, 3224 char *class, char ***perms, int *nperms) 3225 { 3226 struct policydb *policydb = &state->ss->policydb; 3227 int rc, i; 3228 struct class_datum *match; 3229 3230 read_lock(&state->ss->policy_rwlock); 3231 3232 rc = -EINVAL; 3233 match = symtab_search(&policydb->p_classes, class); 3234 if (!match) { 3235 pr_err("SELinux: %s: unrecognized class %s\n", 3236 __func__, class); 3237 goto out; 3238 } 3239 3240 rc = -ENOMEM; 3241 *nperms = match->permissions.nprim; 3242 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); 3243 if (!*perms) 3244 goto out; 3245 3246 if (match->comdatum) { 3247 rc = hashtab_map(&match->comdatum->permissions.table, 3248 get_permissions_callback, *perms); 3249 if (rc) 3250 goto err; 3251 } 3252 3253 rc = hashtab_map(&match->permissions.table, get_permissions_callback, 3254 *perms); 3255 if (rc) 3256 goto err; 3257 3258 out: 3259 read_unlock(&state->ss->policy_rwlock); 3260 return rc; 3261 3262 err: 3263 read_unlock(&state->ss->policy_rwlock); 3264 for (i = 0; i < *nperms; i++) 3265 kfree((*perms)[i]); 3266 kfree(*perms); 3267 return rc; 3268 } 3269 3270 int security_get_reject_unknown(struct selinux_state *state) 3271 { 3272 return state->ss->policydb.reject_unknown; 3273 } 3274 3275 int security_get_allow_unknown(struct selinux_state *state) 3276 { 3277 return state->ss->policydb.allow_unknown; 3278 } 3279 3280 /** 3281 * security_policycap_supported - Check for a specific policy capability 3282 * @req_cap: capability 3283 * 3284 * Description: 3285 * This function queries the currently loaded policy to see if it supports the 3286 * capability specified by @req_cap. Returns true (1) if the capability is 3287 * supported, false (0) if it isn't supported. 3288 * 3289 */ 3290 int security_policycap_supported(struct selinux_state *state, 3291 unsigned int req_cap) 3292 { 3293 struct policydb *policydb = &state->ss->policydb; 3294 int rc; 3295 3296 read_lock(&state->ss->policy_rwlock); 3297 rc = ebitmap_get_bit(&policydb->policycaps, req_cap); 3298 read_unlock(&state->ss->policy_rwlock); 3299 3300 return rc; 3301 } 3302 3303 struct selinux_audit_rule { 3304 u32 au_seqno; 3305 struct context au_ctxt; 3306 }; 3307 3308 void selinux_audit_rule_free(void *vrule) 3309 { 3310 struct selinux_audit_rule *rule = vrule; 3311 3312 if (rule) { 3313 context_destroy(&rule->au_ctxt); 3314 kfree(rule); 3315 } 3316 } 3317 3318 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 3319 { 3320 struct selinux_state *state = &selinux_state; 3321 struct policydb *policydb = &state->ss->policydb; 3322 struct selinux_audit_rule *tmprule; 3323 struct role_datum *roledatum; 3324 struct type_datum *typedatum; 3325 struct user_datum *userdatum; 3326 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; 3327 int rc = 0; 3328 3329 *rule = NULL; 3330 3331 if (!selinux_initialized(state)) 3332 return -EOPNOTSUPP; 3333 3334 switch (field) { 3335 case AUDIT_SUBJ_USER: 3336 case AUDIT_SUBJ_ROLE: 3337 case AUDIT_SUBJ_TYPE: 3338 case AUDIT_OBJ_USER: 3339 case AUDIT_OBJ_ROLE: 3340 case AUDIT_OBJ_TYPE: 3341 /* only 'equals' and 'not equals' fit user, role, and type */ 3342 if (op != Audit_equal && op != Audit_not_equal) 3343 return -EINVAL; 3344 break; 3345 case AUDIT_SUBJ_SEN: 3346 case AUDIT_SUBJ_CLR: 3347 case AUDIT_OBJ_LEV_LOW: 3348 case AUDIT_OBJ_LEV_HIGH: 3349 /* we do not allow a range, indicated by the presence of '-' */ 3350 if (strchr(rulestr, '-')) 3351 return -EINVAL; 3352 break; 3353 default: 3354 /* only the above fields are valid */ 3355 return -EINVAL; 3356 } 3357 3358 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); 3359 if (!tmprule) 3360 return -ENOMEM; 3361 3362 context_init(&tmprule->au_ctxt); 3363 3364 read_lock(&state->ss->policy_rwlock); 3365 3366 tmprule->au_seqno = state->ss->latest_granting; 3367 3368 switch (field) { 3369 case AUDIT_SUBJ_USER: 3370 case AUDIT_OBJ_USER: 3371 rc = -EINVAL; 3372 userdatum = symtab_search(&policydb->p_users, rulestr); 3373 if (!userdatum) 3374 goto out; 3375 tmprule->au_ctxt.user = userdatum->value; 3376 break; 3377 case AUDIT_SUBJ_ROLE: 3378 case AUDIT_OBJ_ROLE: 3379 rc = -EINVAL; 3380 roledatum = symtab_search(&policydb->p_roles, rulestr); 3381 if (!roledatum) 3382 goto out; 3383 tmprule->au_ctxt.role = roledatum->value; 3384 break; 3385 case AUDIT_SUBJ_TYPE: 3386 case AUDIT_OBJ_TYPE: 3387 rc = -EINVAL; 3388 typedatum = symtab_search(&policydb->p_types, rulestr); 3389 if (!typedatum) 3390 goto out; 3391 tmprule->au_ctxt.type = typedatum->value; 3392 break; 3393 case AUDIT_SUBJ_SEN: 3394 case AUDIT_SUBJ_CLR: 3395 case AUDIT_OBJ_LEV_LOW: 3396 case AUDIT_OBJ_LEV_HIGH: 3397 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt, 3398 GFP_ATOMIC); 3399 if (rc) 3400 goto out; 3401 break; 3402 } 3403 rc = 0; 3404 out: 3405 read_unlock(&state->ss->policy_rwlock); 3406 3407 if (rc) { 3408 selinux_audit_rule_free(tmprule); 3409 tmprule = NULL; 3410 } 3411 3412 *rule = tmprule; 3413 3414 return rc; 3415 } 3416 3417 /* Check to see if the rule contains any selinux fields */ 3418 int selinux_audit_rule_known(struct audit_krule *rule) 3419 { 3420 int i; 3421 3422 for (i = 0; i < rule->field_count; i++) { 3423 struct audit_field *f = &rule->fields[i]; 3424 switch (f->type) { 3425 case AUDIT_SUBJ_USER: 3426 case AUDIT_SUBJ_ROLE: 3427 case AUDIT_SUBJ_TYPE: 3428 case AUDIT_SUBJ_SEN: 3429 case AUDIT_SUBJ_CLR: 3430 case AUDIT_OBJ_USER: 3431 case AUDIT_OBJ_ROLE: 3432 case AUDIT_OBJ_TYPE: 3433 case AUDIT_OBJ_LEV_LOW: 3434 case AUDIT_OBJ_LEV_HIGH: 3435 return 1; 3436 } 3437 } 3438 3439 return 0; 3440 } 3441 3442 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) 3443 { 3444 struct selinux_state *state = &selinux_state; 3445 struct context *ctxt; 3446 struct mls_level *level; 3447 struct selinux_audit_rule *rule = vrule; 3448 int match = 0; 3449 3450 if (unlikely(!rule)) { 3451 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n"); 3452 return -ENOENT; 3453 } 3454 3455 read_lock(&state->ss->policy_rwlock); 3456 3457 if (rule->au_seqno < state->ss->latest_granting) { 3458 match = -ESTALE; 3459 goto out; 3460 } 3461 3462 ctxt = sidtab_search(state->ss->sidtab, sid); 3463 if (unlikely(!ctxt)) { 3464 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", 3465 sid); 3466 match = -ENOENT; 3467 goto out; 3468 } 3469 3470 /* a field/op pair that is not caught here will simply fall through 3471 without a match */ 3472 switch (field) { 3473 case AUDIT_SUBJ_USER: 3474 case AUDIT_OBJ_USER: 3475 switch (op) { 3476 case Audit_equal: 3477 match = (ctxt->user == rule->au_ctxt.user); 3478 break; 3479 case Audit_not_equal: 3480 match = (ctxt->user != rule->au_ctxt.user); 3481 break; 3482 } 3483 break; 3484 case AUDIT_SUBJ_ROLE: 3485 case AUDIT_OBJ_ROLE: 3486 switch (op) { 3487 case Audit_equal: 3488 match = (ctxt->role == rule->au_ctxt.role); 3489 break; 3490 case Audit_not_equal: 3491 match = (ctxt->role != rule->au_ctxt.role); 3492 break; 3493 } 3494 break; 3495 case AUDIT_SUBJ_TYPE: 3496 case AUDIT_OBJ_TYPE: 3497 switch (op) { 3498 case Audit_equal: 3499 match = (ctxt->type == rule->au_ctxt.type); 3500 break; 3501 case Audit_not_equal: 3502 match = (ctxt->type != rule->au_ctxt.type); 3503 break; 3504 } 3505 break; 3506 case AUDIT_SUBJ_SEN: 3507 case AUDIT_SUBJ_CLR: 3508 case AUDIT_OBJ_LEV_LOW: 3509 case AUDIT_OBJ_LEV_HIGH: 3510 level = ((field == AUDIT_SUBJ_SEN || 3511 field == AUDIT_OBJ_LEV_LOW) ? 3512 &ctxt->range.level[0] : &ctxt->range.level[1]); 3513 switch (op) { 3514 case Audit_equal: 3515 match = mls_level_eq(&rule->au_ctxt.range.level[0], 3516 level); 3517 break; 3518 case Audit_not_equal: 3519 match = !mls_level_eq(&rule->au_ctxt.range.level[0], 3520 level); 3521 break; 3522 case Audit_lt: 3523 match = (mls_level_dom(&rule->au_ctxt.range.level[0], 3524 level) && 3525 !mls_level_eq(&rule->au_ctxt.range.level[0], 3526 level)); 3527 break; 3528 case Audit_le: 3529 match = mls_level_dom(&rule->au_ctxt.range.level[0], 3530 level); 3531 break; 3532 case Audit_gt: 3533 match = (mls_level_dom(level, 3534 &rule->au_ctxt.range.level[0]) && 3535 !mls_level_eq(level, 3536 &rule->au_ctxt.range.level[0])); 3537 break; 3538 case Audit_ge: 3539 match = mls_level_dom(level, 3540 &rule->au_ctxt.range.level[0]); 3541 break; 3542 } 3543 } 3544 3545 out: 3546 read_unlock(&state->ss->policy_rwlock); 3547 return match; 3548 } 3549 3550 static int (*aurule_callback)(void) = audit_update_lsm_rules; 3551 3552 static int aurule_avc_callback(u32 event) 3553 { 3554 int err = 0; 3555 3556 if (event == AVC_CALLBACK_RESET && aurule_callback) 3557 err = aurule_callback(); 3558 return err; 3559 } 3560 3561 static int __init aurule_init(void) 3562 { 3563 int err; 3564 3565 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET); 3566 if (err) 3567 panic("avc_add_callback() failed, error %d\n", err); 3568 3569 return err; 3570 } 3571 __initcall(aurule_init); 3572 3573 #ifdef CONFIG_NETLABEL 3574 /** 3575 * security_netlbl_cache_add - Add an entry to the NetLabel cache 3576 * @secattr: the NetLabel packet security attributes 3577 * @sid: the SELinux SID 3578 * 3579 * Description: 3580 * Attempt to cache the context in @ctx, which was derived from the packet in 3581 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has 3582 * already been initialized. 3583 * 3584 */ 3585 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, 3586 u32 sid) 3587 { 3588 u32 *sid_cache; 3589 3590 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); 3591 if (sid_cache == NULL) 3592 return; 3593 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); 3594 if (secattr->cache == NULL) { 3595 kfree(sid_cache); 3596 return; 3597 } 3598 3599 *sid_cache = sid; 3600 secattr->cache->free = kfree; 3601 secattr->cache->data = sid_cache; 3602 secattr->flags |= NETLBL_SECATTR_CACHE; 3603 } 3604 3605 /** 3606 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID 3607 * @secattr: the NetLabel packet security attributes 3608 * @sid: the SELinux SID 3609 * 3610 * Description: 3611 * Convert the given NetLabel security attributes in @secattr into a 3612 * SELinux SID. If the @secattr field does not contain a full SELinux 3613 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the 3614 * 'cache' field of @secattr is set and the CACHE flag is set; this is to 3615 * allow the @secattr to be used by NetLabel to cache the secattr to SID 3616 * conversion for future lookups. Returns zero on success, negative values on 3617 * failure. 3618 * 3619 */ 3620 int security_netlbl_secattr_to_sid(struct selinux_state *state, 3621 struct netlbl_lsm_secattr *secattr, 3622 u32 *sid) 3623 { 3624 struct policydb *policydb = &state->ss->policydb; 3625 struct sidtab *sidtab = state->ss->sidtab; 3626 int rc; 3627 struct context *ctx; 3628 struct context ctx_new; 3629 3630 if (!selinux_initialized(state)) { 3631 *sid = SECSID_NULL; 3632 return 0; 3633 } 3634 3635 read_lock(&state->ss->policy_rwlock); 3636 3637 if (secattr->flags & NETLBL_SECATTR_CACHE) 3638 *sid = *(u32 *)secattr->cache->data; 3639 else if (secattr->flags & NETLBL_SECATTR_SECID) 3640 *sid = secattr->attr.secid; 3641 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { 3642 rc = -EIDRM; 3643 ctx = sidtab_search(sidtab, SECINITSID_NETMSG); 3644 if (ctx == NULL) 3645 goto out; 3646 3647 context_init(&ctx_new); 3648 ctx_new.user = ctx->user; 3649 ctx_new.role = ctx->role; 3650 ctx_new.type = ctx->type; 3651 mls_import_netlbl_lvl(policydb, &ctx_new, secattr); 3652 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { 3653 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr); 3654 if (rc) 3655 goto out; 3656 } 3657 rc = -EIDRM; 3658 if (!mls_context_isvalid(policydb, &ctx_new)) 3659 goto out_free; 3660 3661 rc = sidtab_context_to_sid(sidtab, &ctx_new, sid); 3662 if (rc) 3663 goto out_free; 3664 3665 security_netlbl_cache_add(secattr, *sid); 3666 3667 ebitmap_destroy(&ctx_new.range.level[0].cat); 3668 } else 3669 *sid = SECSID_NULL; 3670 3671 read_unlock(&state->ss->policy_rwlock); 3672 return 0; 3673 out_free: 3674 ebitmap_destroy(&ctx_new.range.level[0].cat); 3675 out: 3676 read_unlock(&state->ss->policy_rwlock); 3677 return rc; 3678 } 3679 3680 /** 3681 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr 3682 * @sid: the SELinux SID 3683 * @secattr: the NetLabel packet security attributes 3684 * 3685 * Description: 3686 * Convert the given SELinux SID in @sid into a NetLabel security attribute. 3687 * Returns zero on success, negative values on failure. 3688 * 3689 */ 3690 int security_netlbl_sid_to_secattr(struct selinux_state *state, 3691 u32 sid, struct netlbl_lsm_secattr *secattr) 3692 { 3693 struct policydb *policydb = &state->ss->policydb; 3694 int rc; 3695 struct context *ctx; 3696 3697 if (!selinux_initialized(state)) 3698 return 0; 3699 3700 read_lock(&state->ss->policy_rwlock); 3701 3702 rc = -ENOENT; 3703 ctx = sidtab_search(state->ss->sidtab, sid); 3704 if (ctx == NULL) 3705 goto out; 3706 3707 rc = -ENOMEM; 3708 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1), 3709 GFP_ATOMIC); 3710 if (secattr->domain == NULL) 3711 goto out; 3712 3713 secattr->attr.secid = sid; 3714 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; 3715 mls_export_netlbl_lvl(policydb, ctx, secattr); 3716 rc = mls_export_netlbl_cat(policydb, ctx, secattr); 3717 out: 3718 read_unlock(&state->ss->policy_rwlock); 3719 return rc; 3720 } 3721 #endif /* CONFIG_NETLABEL */ 3722 3723 /** 3724 * security_read_policy - read the policy. 3725 * @data: binary policy data 3726 * @len: length of data in bytes 3727 * 3728 */ 3729 int security_read_policy(struct selinux_state *state, 3730 void **data, size_t *len) 3731 { 3732 struct policydb *policydb = &state->ss->policydb; 3733 int rc; 3734 struct policy_file fp; 3735 3736 if (!selinux_initialized(state)) 3737 return -EINVAL; 3738 3739 *len = security_policydb_len(state); 3740 3741 *data = vmalloc_user(*len); 3742 if (!*data) 3743 return -ENOMEM; 3744 3745 fp.data = *data; 3746 fp.len = *len; 3747 3748 read_lock(&state->ss->policy_rwlock); 3749 rc = policydb_write(policydb, &fp); 3750 read_unlock(&state->ss->policy_rwlock); 3751 3752 if (rc) 3753 return rc; 3754 3755 *len = (unsigned long)fp.data - (unsigned long)*data; 3756 return 0; 3757 3758 } 3759