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 = hashtab_search(pol->p_users.table, 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 = hashtab_search(pol->p_roles.table, 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 = hashtab_search(pol->p_types.table, 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 int context_add_hash(struct policydb *policydb, 1494 struct context *context) 1495 { 1496 int rc; 1497 char *str; 1498 int len; 1499 1500 if (context->str) { 1501 context->hash = context_compute_hash(context->str); 1502 } else { 1503 rc = context_struct_to_string(policydb, context, 1504 &str, &len); 1505 if (rc) 1506 return rc; 1507 context->hash = context_compute_hash(str); 1508 kfree(str); 1509 } 1510 return 0; 1511 } 1512 1513 static int context_struct_to_sid(struct selinux_state *state, 1514 struct context *context, u32 *sid) 1515 { 1516 int rc; 1517 struct sidtab *sidtab = state->ss->sidtab; 1518 struct policydb *policydb = &state->ss->policydb; 1519 1520 if (!context->hash) { 1521 rc = context_add_hash(policydb, context); 1522 if (rc) 1523 return rc; 1524 } 1525 1526 return sidtab_context_to_sid(sidtab, context, sid); 1527 } 1528 1529 static int security_context_to_sid_core(struct selinux_state *state, 1530 const char *scontext, u32 scontext_len, 1531 u32 *sid, u32 def_sid, gfp_t gfp_flags, 1532 int force) 1533 { 1534 struct policydb *policydb; 1535 struct sidtab *sidtab; 1536 char *scontext2, *str = NULL; 1537 struct context context; 1538 int rc = 0; 1539 1540 /* An empty security context is never valid. */ 1541 if (!scontext_len) 1542 return -EINVAL; 1543 1544 /* Copy the string to allow changes and ensure a NUL terminator */ 1545 scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags); 1546 if (!scontext2) 1547 return -ENOMEM; 1548 1549 if (!selinux_initialized(state)) { 1550 int i; 1551 1552 for (i = 1; i < SECINITSID_NUM; i++) { 1553 const char *s = initial_sid_to_string[i]; 1554 1555 if (s && !strcmp(s, scontext2)) { 1556 *sid = i; 1557 goto out; 1558 } 1559 } 1560 *sid = SECINITSID_KERNEL; 1561 goto out; 1562 } 1563 *sid = SECSID_NULL; 1564 1565 if (force) { 1566 /* Save another copy for storing in uninterpreted form */ 1567 rc = -ENOMEM; 1568 str = kstrdup(scontext2, gfp_flags); 1569 if (!str) 1570 goto out; 1571 } 1572 read_lock(&state->ss->policy_rwlock); 1573 policydb = &state->ss->policydb; 1574 sidtab = state->ss->sidtab; 1575 rc = string_to_context_struct(policydb, sidtab, scontext2, 1576 &context, def_sid); 1577 if (rc == -EINVAL && force) { 1578 context.str = str; 1579 context.len = strlen(str) + 1; 1580 str = NULL; 1581 } else if (rc) 1582 goto out_unlock; 1583 rc = context_struct_to_sid(state, &context, sid); 1584 context_destroy(&context); 1585 out_unlock: 1586 read_unlock(&state->ss->policy_rwlock); 1587 out: 1588 kfree(scontext2); 1589 kfree(str); 1590 return rc; 1591 } 1592 1593 /** 1594 * security_context_to_sid - Obtain a SID for a given security context. 1595 * @scontext: security context 1596 * @scontext_len: length in bytes 1597 * @sid: security identifier, SID 1598 * @gfp: context for the allocation 1599 * 1600 * Obtains a SID associated with the security context that 1601 * has the string representation specified by @scontext. 1602 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1603 * memory is available, or 0 on success. 1604 */ 1605 int security_context_to_sid(struct selinux_state *state, 1606 const char *scontext, u32 scontext_len, u32 *sid, 1607 gfp_t gfp) 1608 { 1609 return security_context_to_sid_core(state, scontext, scontext_len, 1610 sid, SECSID_NULL, gfp, 0); 1611 } 1612 1613 int security_context_str_to_sid(struct selinux_state *state, 1614 const char *scontext, u32 *sid, gfp_t gfp) 1615 { 1616 return security_context_to_sid(state, scontext, strlen(scontext), 1617 sid, gfp); 1618 } 1619 1620 /** 1621 * security_context_to_sid_default - Obtain a SID for a given security context, 1622 * falling back to specified default if needed. 1623 * 1624 * @scontext: security context 1625 * @scontext_len: length in bytes 1626 * @sid: security identifier, SID 1627 * @def_sid: default SID to assign on error 1628 * 1629 * Obtains a SID associated with the security context that 1630 * has the string representation specified by @scontext. 1631 * The default SID is passed to the MLS layer to be used to allow 1632 * kernel labeling of the MLS field if the MLS field is not present 1633 * (for upgrading to MLS without full relabel). 1634 * Implicitly forces adding of the context even if it cannot be mapped yet. 1635 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1636 * memory is available, or 0 on success. 1637 */ 1638 int security_context_to_sid_default(struct selinux_state *state, 1639 const char *scontext, u32 scontext_len, 1640 u32 *sid, u32 def_sid, gfp_t gfp_flags) 1641 { 1642 return security_context_to_sid_core(state, scontext, scontext_len, 1643 sid, def_sid, gfp_flags, 1); 1644 } 1645 1646 int security_context_to_sid_force(struct selinux_state *state, 1647 const char *scontext, u32 scontext_len, 1648 u32 *sid) 1649 { 1650 return security_context_to_sid_core(state, scontext, scontext_len, 1651 sid, SECSID_NULL, GFP_KERNEL, 1); 1652 } 1653 1654 static int compute_sid_handle_invalid_context( 1655 struct selinux_state *state, 1656 struct sidtab_entry *sentry, 1657 struct sidtab_entry *tentry, 1658 u16 tclass, 1659 struct context *newcontext) 1660 { 1661 struct policydb *policydb = &state->ss->policydb; 1662 struct sidtab *sidtab = state->ss->sidtab; 1663 char *s = NULL, *t = NULL, *n = NULL; 1664 u32 slen, tlen, nlen; 1665 struct audit_buffer *ab; 1666 1667 if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen)) 1668 goto out; 1669 if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen)) 1670 goto out; 1671 if (context_struct_to_string(policydb, newcontext, &n, &nlen)) 1672 goto out; 1673 ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); 1674 audit_log_format(ab, 1675 "op=security_compute_sid invalid_context="); 1676 /* no need to record the NUL with untrusted strings */ 1677 audit_log_n_untrustedstring(ab, n, nlen - 1); 1678 audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s", 1679 s, t, sym_name(policydb, SYM_CLASSES, tclass-1)); 1680 audit_log_end(ab); 1681 out: 1682 kfree(s); 1683 kfree(t); 1684 kfree(n); 1685 if (!enforcing_enabled(state)) 1686 return 0; 1687 return -EACCES; 1688 } 1689 1690 static void filename_compute_type(struct policydb *policydb, 1691 struct context *newcontext, 1692 u32 stype, u32 ttype, u16 tclass, 1693 const char *objname) 1694 { 1695 struct filename_trans_key ft; 1696 struct filename_trans_datum *datum; 1697 1698 /* 1699 * Most filename trans rules are going to live in specific directories 1700 * like /dev or /var/run. This bitmap will quickly skip rule searches 1701 * if the ttype does not contain any rules. 1702 */ 1703 if (!ebitmap_get_bit(&policydb->filename_trans_ttypes, ttype)) 1704 return; 1705 1706 ft.ttype = ttype; 1707 ft.tclass = tclass; 1708 ft.name = objname; 1709 1710 datum = hashtab_search(policydb->filename_trans, &ft); 1711 while (datum) { 1712 if (ebitmap_get_bit(&datum->stypes, stype - 1)) { 1713 newcontext->type = datum->otype; 1714 return; 1715 } 1716 datum = datum->next; 1717 } 1718 } 1719 1720 static int security_compute_sid(struct selinux_state *state, 1721 u32 ssid, 1722 u32 tsid, 1723 u16 orig_tclass, 1724 u32 specified, 1725 const char *objname, 1726 u32 *out_sid, 1727 bool kern) 1728 { 1729 struct policydb *policydb; 1730 struct sidtab *sidtab; 1731 struct class_datum *cladatum = NULL; 1732 struct context *scontext, *tcontext, newcontext; 1733 struct sidtab_entry *sentry, *tentry; 1734 struct role_trans *roletr = NULL; 1735 struct avtab_key avkey; 1736 struct avtab_datum *avdatum; 1737 struct avtab_node *node; 1738 u16 tclass; 1739 int rc = 0; 1740 bool sock; 1741 1742 if (!selinux_initialized(state)) { 1743 switch (orig_tclass) { 1744 case SECCLASS_PROCESS: /* kernel value */ 1745 *out_sid = ssid; 1746 break; 1747 default: 1748 *out_sid = tsid; 1749 break; 1750 } 1751 goto out; 1752 } 1753 1754 context_init(&newcontext); 1755 1756 read_lock(&state->ss->policy_rwlock); 1757 1758 if (kern) { 1759 tclass = unmap_class(&state->ss->map, orig_tclass); 1760 sock = security_is_socket_class(orig_tclass); 1761 } else { 1762 tclass = orig_tclass; 1763 sock = security_is_socket_class(map_class(&state->ss->map, 1764 tclass)); 1765 } 1766 1767 policydb = &state->ss->policydb; 1768 sidtab = state->ss->sidtab; 1769 1770 sentry = sidtab_search_entry(sidtab, ssid); 1771 if (!sentry) { 1772 pr_err("SELinux: %s: unrecognized SID %d\n", 1773 __func__, ssid); 1774 rc = -EINVAL; 1775 goto out_unlock; 1776 } 1777 tentry = sidtab_search_entry(sidtab, tsid); 1778 if (!tentry) { 1779 pr_err("SELinux: %s: unrecognized SID %d\n", 1780 __func__, tsid); 1781 rc = -EINVAL; 1782 goto out_unlock; 1783 } 1784 1785 scontext = &sentry->context; 1786 tcontext = &tentry->context; 1787 1788 if (tclass && tclass <= policydb->p_classes.nprim) 1789 cladatum = policydb->class_val_to_struct[tclass - 1]; 1790 1791 /* Set the user identity. */ 1792 switch (specified) { 1793 case AVTAB_TRANSITION: 1794 case AVTAB_CHANGE: 1795 if (cladatum && cladatum->default_user == DEFAULT_TARGET) { 1796 newcontext.user = tcontext->user; 1797 } else { 1798 /* notice this gets both DEFAULT_SOURCE and unset */ 1799 /* Use the process user identity. */ 1800 newcontext.user = scontext->user; 1801 } 1802 break; 1803 case AVTAB_MEMBER: 1804 /* Use the related object owner. */ 1805 newcontext.user = tcontext->user; 1806 break; 1807 } 1808 1809 /* Set the role to default values. */ 1810 if (cladatum && cladatum->default_role == DEFAULT_SOURCE) { 1811 newcontext.role = scontext->role; 1812 } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { 1813 newcontext.role = tcontext->role; 1814 } else { 1815 if ((tclass == policydb->process_class) || (sock == true)) 1816 newcontext.role = scontext->role; 1817 else 1818 newcontext.role = OBJECT_R_VAL; 1819 } 1820 1821 /* Set the type to default values. */ 1822 if (cladatum && cladatum->default_type == DEFAULT_SOURCE) { 1823 newcontext.type = scontext->type; 1824 } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { 1825 newcontext.type = tcontext->type; 1826 } else { 1827 if ((tclass == policydb->process_class) || (sock == true)) { 1828 /* Use the type of process. */ 1829 newcontext.type = scontext->type; 1830 } else { 1831 /* Use the type of the related object. */ 1832 newcontext.type = tcontext->type; 1833 } 1834 } 1835 1836 /* Look for a type transition/member/change rule. */ 1837 avkey.source_type = scontext->type; 1838 avkey.target_type = tcontext->type; 1839 avkey.target_class = tclass; 1840 avkey.specified = specified; 1841 avdatum = avtab_search(&policydb->te_avtab, &avkey); 1842 1843 /* If no permanent rule, also check for enabled conditional rules */ 1844 if (!avdatum) { 1845 node = avtab_search_node(&policydb->te_cond_avtab, &avkey); 1846 for (; node; node = avtab_search_node_next(node, specified)) { 1847 if (node->key.specified & AVTAB_ENABLED) { 1848 avdatum = &node->datum; 1849 break; 1850 } 1851 } 1852 } 1853 1854 if (avdatum) { 1855 /* Use the type from the type transition/member/change rule. */ 1856 newcontext.type = avdatum->u.data; 1857 } 1858 1859 /* if we have a objname this is a file trans check so check those rules */ 1860 if (objname) 1861 filename_compute_type(policydb, &newcontext, scontext->type, 1862 tcontext->type, tclass, objname); 1863 1864 /* Check for class-specific changes. */ 1865 if (specified & AVTAB_TRANSITION) { 1866 /* Look for a role transition rule. */ 1867 for (roletr = policydb->role_tr; roletr; 1868 roletr = roletr->next) { 1869 if ((roletr->role == scontext->role) && 1870 (roletr->type == tcontext->type) && 1871 (roletr->tclass == tclass)) { 1872 /* Use the role transition rule. */ 1873 newcontext.role = roletr->new_role; 1874 break; 1875 } 1876 } 1877 } 1878 1879 /* Set the MLS attributes. 1880 This is done last because it may allocate memory. */ 1881 rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified, 1882 &newcontext, sock); 1883 if (rc) 1884 goto out_unlock; 1885 1886 /* Check the validity of the context. */ 1887 if (!policydb_context_isvalid(policydb, &newcontext)) { 1888 rc = compute_sid_handle_invalid_context(state, sentry, tentry, 1889 tclass, &newcontext); 1890 if (rc) 1891 goto out_unlock; 1892 } 1893 /* Obtain the sid for the context. */ 1894 rc = context_struct_to_sid(state, &newcontext, out_sid); 1895 out_unlock: 1896 read_unlock(&state->ss->policy_rwlock); 1897 context_destroy(&newcontext); 1898 out: 1899 return rc; 1900 } 1901 1902 /** 1903 * security_transition_sid - Compute the SID for a new subject/object. 1904 * @ssid: source security identifier 1905 * @tsid: target security identifier 1906 * @tclass: target security class 1907 * @out_sid: security identifier for new subject/object 1908 * 1909 * Compute a SID to use for labeling a new subject or object in the 1910 * class @tclass based on a SID pair (@ssid, @tsid). 1911 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1912 * if insufficient memory is available, or %0 if the new SID was 1913 * computed successfully. 1914 */ 1915 int security_transition_sid(struct selinux_state *state, 1916 u32 ssid, u32 tsid, u16 tclass, 1917 const struct qstr *qstr, u32 *out_sid) 1918 { 1919 return security_compute_sid(state, ssid, tsid, tclass, 1920 AVTAB_TRANSITION, 1921 qstr ? qstr->name : NULL, out_sid, true); 1922 } 1923 1924 int security_transition_sid_user(struct selinux_state *state, 1925 u32 ssid, u32 tsid, u16 tclass, 1926 const char *objname, u32 *out_sid) 1927 { 1928 return security_compute_sid(state, ssid, tsid, tclass, 1929 AVTAB_TRANSITION, 1930 objname, out_sid, false); 1931 } 1932 1933 /** 1934 * security_member_sid - Compute the SID for member selection. 1935 * @ssid: source security identifier 1936 * @tsid: target security identifier 1937 * @tclass: target security class 1938 * @out_sid: security identifier for selected member 1939 * 1940 * Compute a SID to use when selecting a member of a polyinstantiated 1941 * object of class @tclass based on a SID pair (@ssid, @tsid). 1942 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1943 * if insufficient memory is available, or %0 if the SID was 1944 * computed successfully. 1945 */ 1946 int security_member_sid(struct selinux_state *state, 1947 u32 ssid, 1948 u32 tsid, 1949 u16 tclass, 1950 u32 *out_sid) 1951 { 1952 return security_compute_sid(state, ssid, tsid, tclass, 1953 AVTAB_MEMBER, NULL, 1954 out_sid, false); 1955 } 1956 1957 /** 1958 * security_change_sid - Compute the SID for object relabeling. 1959 * @ssid: source security identifier 1960 * @tsid: target security identifier 1961 * @tclass: target security class 1962 * @out_sid: security identifier for selected member 1963 * 1964 * Compute a SID to use for relabeling an object of class @tclass 1965 * based on a SID pair (@ssid, @tsid). 1966 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1967 * if insufficient memory is available, or %0 if the SID was 1968 * computed successfully. 1969 */ 1970 int security_change_sid(struct selinux_state *state, 1971 u32 ssid, 1972 u32 tsid, 1973 u16 tclass, 1974 u32 *out_sid) 1975 { 1976 return security_compute_sid(state, 1977 ssid, tsid, tclass, AVTAB_CHANGE, NULL, 1978 out_sid, false); 1979 } 1980 1981 static inline int convert_context_handle_invalid_context( 1982 struct selinux_state *state, 1983 struct context *context) 1984 { 1985 struct policydb *policydb = &state->ss->policydb; 1986 char *s; 1987 u32 len; 1988 1989 if (enforcing_enabled(state)) 1990 return -EINVAL; 1991 1992 if (!context_struct_to_string(policydb, context, &s, &len)) { 1993 pr_warn("SELinux: Context %s would be invalid if enforcing\n", 1994 s); 1995 kfree(s); 1996 } 1997 return 0; 1998 } 1999 2000 struct convert_context_args { 2001 struct selinux_state *state; 2002 struct policydb *oldp; 2003 struct policydb *newp; 2004 }; 2005 2006 /* 2007 * Convert the values in the security context 2008 * structure `oldc' from the values specified 2009 * in the policy `p->oldp' to the values specified 2010 * in the policy `p->newp', storing the new context 2011 * in `newc'. Verify that the context is valid 2012 * under the new policy. 2013 */ 2014 static int convert_context(struct context *oldc, struct context *newc, void *p) 2015 { 2016 struct convert_context_args *args; 2017 struct ocontext *oc; 2018 struct role_datum *role; 2019 struct type_datum *typdatum; 2020 struct user_datum *usrdatum; 2021 char *s; 2022 u32 len; 2023 int rc; 2024 2025 args = p; 2026 2027 if (oldc->str) { 2028 s = kstrdup(oldc->str, GFP_KERNEL); 2029 if (!s) 2030 return -ENOMEM; 2031 2032 rc = string_to_context_struct(args->newp, NULL, s, 2033 newc, SECSID_NULL); 2034 if (rc == -EINVAL) { 2035 /* 2036 * Retain string representation for later mapping. 2037 * 2038 * IMPORTANT: We need to copy the contents of oldc->str 2039 * back into s again because string_to_context_struct() 2040 * may have garbled it. 2041 */ 2042 memcpy(s, oldc->str, oldc->len); 2043 context_init(newc); 2044 newc->str = s; 2045 newc->len = oldc->len; 2046 newc->hash = oldc->hash; 2047 return 0; 2048 } 2049 kfree(s); 2050 if (rc) { 2051 /* Other error condition, e.g. ENOMEM. */ 2052 pr_err("SELinux: Unable to map context %s, rc = %d.\n", 2053 oldc->str, -rc); 2054 return rc; 2055 } 2056 pr_info("SELinux: Context %s became valid (mapped).\n", 2057 oldc->str); 2058 return 0; 2059 } 2060 2061 context_init(newc); 2062 2063 /* Convert the user. */ 2064 rc = -EINVAL; 2065 usrdatum = hashtab_search(args->newp->p_users.table, 2066 sym_name(args->oldp, 2067 SYM_USERS, oldc->user - 1)); 2068 if (!usrdatum) 2069 goto bad; 2070 newc->user = usrdatum->value; 2071 2072 /* Convert the role. */ 2073 rc = -EINVAL; 2074 role = hashtab_search(args->newp->p_roles.table, 2075 sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); 2076 if (!role) 2077 goto bad; 2078 newc->role = role->value; 2079 2080 /* Convert the type. */ 2081 rc = -EINVAL; 2082 typdatum = hashtab_search(args->newp->p_types.table, 2083 sym_name(args->oldp, 2084 SYM_TYPES, oldc->type - 1)); 2085 if (!typdatum) 2086 goto bad; 2087 newc->type = typdatum->value; 2088 2089 /* Convert the MLS fields if dealing with MLS policies */ 2090 if (args->oldp->mls_enabled && args->newp->mls_enabled) { 2091 rc = mls_convert_context(args->oldp, args->newp, oldc, newc); 2092 if (rc) 2093 goto bad; 2094 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { 2095 /* 2096 * Switching between non-MLS and MLS policy: 2097 * ensure that the MLS fields of the context for all 2098 * existing entries in the sidtab are filled in with a 2099 * suitable default value, likely taken from one of the 2100 * initial SIDs. 2101 */ 2102 oc = args->newp->ocontexts[OCON_ISID]; 2103 while (oc && oc->sid[0] != SECINITSID_UNLABELED) 2104 oc = oc->next; 2105 rc = -EINVAL; 2106 if (!oc) { 2107 pr_err("SELinux: unable to look up" 2108 " the initial SIDs list\n"); 2109 goto bad; 2110 } 2111 rc = mls_range_set(newc, &oc->context[0].range); 2112 if (rc) 2113 goto bad; 2114 } 2115 2116 /* Check the validity of the new context. */ 2117 if (!policydb_context_isvalid(args->newp, newc)) { 2118 rc = convert_context_handle_invalid_context(args->state, oldc); 2119 if (rc) 2120 goto bad; 2121 } 2122 2123 rc = context_add_hash(args->newp, newc); 2124 if (rc) 2125 goto bad; 2126 2127 return 0; 2128 bad: 2129 /* Map old representation to string and save it. */ 2130 rc = context_struct_to_string(args->oldp, oldc, &s, &len); 2131 if (rc) 2132 return rc; 2133 context_destroy(newc); 2134 newc->str = s; 2135 newc->len = len; 2136 newc->hash = context_compute_hash(s); 2137 pr_info("SELinux: Context %s became invalid (unmapped).\n", 2138 newc->str); 2139 return 0; 2140 } 2141 2142 static void security_load_policycaps(struct selinux_state *state) 2143 { 2144 struct policydb *p = &state->ss->policydb; 2145 unsigned int i; 2146 struct ebitmap_node *node; 2147 2148 for (i = 0; i < ARRAY_SIZE(state->policycap); i++) 2149 state->policycap[i] = ebitmap_get_bit(&p->policycaps, i); 2150 2151 for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) 2152 pr_info("SELinux: policy capability %s=%d\n", 2153 selinux_policycap_names[i], 2154 ebitmap_get_bit(&p->policycaps, i)); 2155 2156 ebitmap_for_each_positive_bit(&p->policycaps, node, i) { 2157 if (i >= ARRAY_SIZE(selinux_policycap_names)) 2158 pr_info("SELinux: unknown policy capability %u\n", 2159 i); 2160 } 2161 } 2162 2163 static int security_preserve_bools(struct selinux_state *state, 2164 struct policydb *newpolicydb); 2165 2166 /** 2167 * security_load_policy - Load a security policy configuration. 2168 * @data: binary policy data 2169 * @len: length of data in bytes 2170 * 2171 * Load a new set of security policy configuration data, 2172 * validate it and convert the SID table as necessary. 2173 * This function will flush the access vector cache after 2174 * loading the new policy. 2175 */ 2176 int security_load_policy(struct selinux_state *state, void *data, size_t len) 2177 { 2178 struct policydb *policydb; 2179 struct sidtab *oldsidtab, *newsidtab; 2180 struct policydb *oldpolicydb, *newpolicydb; 2181 struct selinux_mapping *oldmapping; 2182 struct selinux_map newmap; 2183 struct sidtab_convert_params convert_params; 2184 struct convert_context_args args; 2185 u32 seqno; 2186 int rc = 0; 2187 struct policy_file file = { data, len }, *fp = &file; 2188 2189 policydb = &state->ss->policydb; 2190 2191 newsidtab = kmalloc(sizeof(*newsidtab), GFP_KERNEL); 2192 if (!newsidtab) 2193 return -ENOMEM; 2194 2195 if (!selinux_initialized(state)) { 2196 rc = policydb_read(policydb, fp); 2197 if (rc) { 2198 kfree(newsidtab); 2199 return rc; 2200 } 2201 2202 policydb->len = len; 2203 rc = selinux_set_mapping(policydb, secclass_map, 2204 &state->ss->map); 2205 if (rc) { 2206 kfree(newsidtab); 2207 policydb_destroy(policydb); 2208 return rc; 2209 } 2210 2211 rc = policydb_load_isids(policydb, newsidtab); 2212 if (rc) { 2213 kfree(newsidtab); 2214 policydb_destroy(policydb); 2215 return rc; 2216 } 2217 2218 state->ss->sidtab = newsidtab; 2219 security_load_policycaps(state); 2220 selinux_mark_initialized(state); 2221 seqno = ++state->ss->latest_granting; 2222 selinux_complete_init(); 2223 avc_ss_reset(state->avc, seqno); 2224 selnl_notify_policyload(seqno); 2225 selinux_status_update_policyload(state, seqno); 2226 selinux_netlbl_cache_invalidate(); 2227 selinux_xfrm_notify_policyload(); 2228 return 0; 2229 } 2230 2231 oldpolicydb = kcalloc(2, sizeof(*oldpolicydb), GFP_KERNEL); 2232 if (!oldpolicydb) { 2233 kfree(newsidtab); 2234 return -ENOMEM; 2235 } 2236 newpolicydb = oldpolicydb + 1; 2237 2238 rc = policydb_read(newpolicydb, fp); 2239 if (rc) { 2240 kfree(newsidtab); 2241 goto out; 2242 } 2243 2244 newpolicydb->len = len; 2245 /* If switching between different policy types, log MLS status */ 2246 if (policydb->mls_enabled && !newpolicydb->mls_enabled) 2247 pr_info("SELinux: Disabling MLS support...\n"); 2248 else if (!policydb->mls_enabled && newpolicydb->mls_enabled) 2249 pr_info("SELinux: Enabling MLS support...\n"); 2250 2251 rc = policydb_load_isids(newpolicydb, newsidtab); 2252 if (rc) { 2253 pr_err("SELinux: unable to load the initial SIDs\n"); 2254 policydb_destroy(newpolicydb); 2255 kfree(newsidtab); 2256 goto out; 2257 } 2258 2259 rc = selinux_set_mapping(newpolicydb, secclass_map, &newmap); 2260 if (rc) 2261 goto err; 2262 2263 rc = security_preserve_bools(state, newpolicydb); 2264 if (rc) { 2265 pr_err("SELinux: unable to preserve booleans\n"); 2266 goto err; 2267 } 2268 2269 oldsidtab = state->ss->sidtab; 2270 2271 /* 2272 * Convert the internal representations of contexts 2273 * in the new SID table. 2274 */ 2275 args.state = state; 2276 args.oldp = policydb; 2277 args.newp = newpolicydb; 2278 2279 convert_params.func = convert_context; 2280 convert_params.args = &args; 2281 convert_params.target = newsidtab; 2282 2283 rc = sidtab_convert(oldsidtab, &convert_params); 2284 if (rc) { 2285 pr_err("SELinux: unable to convert the internal" 2286 " representation of contexts in the new SID" 2287 " table\n"); 2288 goto err; 2289 } 2290 2291 /* Save the old policydb and SID table to free later. */ 2292 memcpy(oldpolicydb, policydb, sizeof(*policydb)); 2293 2294 /* Install the new policydb and SID table. */ 2295 write_lock_irq(&state->ss->policy_rwlock); 2296 memcpy(policydb, newpolicydb, sizeof(*policydb)); 2297 state->ss->sidtab = newsidtab; 2298 security_load_policycaps(state); 2299 oldmapping = state->ss->map.mapping; 2300 state->ss->map.mapping = newmap.mapping; 2301 state->ss->map.size = newmap.size; 2302 seqno = ++state->ss->latest_granting; 2303 write_unlock_irq(&state->ss->policy_rwlock); 2304 2305 /* Free the old policydb and SID table. */ 2306 policydb_destroy(oldpolicydb); 2307 sidtab_destroy(oldsidtab); 2308 kfree(oldsidtab); 2309 kfree(oldmapping); 2310 2311 avc_ss_reset(state->avc, seqno); 2312 selnl_notify_policyload(seqno); 2313 selinux_status_update_policyload(state, seqno); 2314 selinux_netlbl_cache_invalidate(); 2315 selinux_xfrm_notify_policyload(); 2316 2317 rc = 0; 2318 goto out; 2319 2320 err: 2321 kfree(newmap.mapping); 2322 sidtab_destroy(newsidtab); 2323 kfree(newsidtab); 2324 policydb_destroy(newpolicydb); 2325 2326 out: 2327 kfree(oldpolicydb); 2328 return rc; 2329 } 2330 2331 size_t security_policydb_len(struct selinux_state *state) 2332 { 2333 struct policydb *p = &state->ss->policydb; 2334 size_t len; 2335 2336 read_lock(&state->ss->policy_rwlock); 2337 len = p->len; 2338 read_unlock(&state->ss->policy_rwlock); 2339 2340 return len; 2341 } 2342 2343 /** 2344 * security_port_sid - Obtain the SID for a port. 2345 * @protocol: protocol number 2346 * @port: port number 2347 * @out_sid: security identifier 2348 */ 2349 int security_port_sid(struct selinux_state *state, 2350 u8 protocol, u16 port, u32 *out_sid) 2351 { 2352 struct policydb *policydb; 2353 struct ocontext *c; 2354 int rc = 0; 2355 2356 read_lock(&state->ss->policy_rwlock); 2357 2358 policydb = &state->ss->policydb; 2359 2360 c = policydb->ocontexts[OCON_PORT]; 2361 while (c) { 2362 if (c->u.port.protocol == protocol && 2363 c->u.port.low_port <= port && 2364 c->u.port.high_port >= port) 2365 break; 2366 c = c->next; 2367 } 2368 2369 if (c) { 2370 if (!c->sid[0]) { 2371 rc = context_struct_to_sid(state, &c->context[0], 2372 &c->sid[0]); 2373 if (rc) 2374 goto out; 2375 } 2376 *out_sid = c->sid[0]; 2377 } else { 2378 *out_sid = SECINITSID_PORT; 2379 } 2380 2381 out: 2382 read_unlock(&state->ss->policy_rwlock); 2383 return rc; 2384 } 2385 2386 /** 2387 * security_pkey_sid - Obtain the SID for a pkey. 2388 * @subnet_prefix: Subnet Prefix 2389 * @pkey_num: pkey number 2390 * @out_sid: security identifier 2391 */ 2392 int security_ib_pkey_sid(struct selinux_state *state, 2393 u64 subnet_prefix, u16 pkey_num, u32 *out_sid) 2394 { 2395 struct policydb *policydb; 2396 struct ocontext *c; 2397 int rc = 0; 2398 2399 read_lock(&state->ss->policy_rwlock); 2400 2401 policydb = &state->ss->policydb; 2402 2403 c = policydb->ocontexts[OCON_IBPKEY]; 2404 while (c) { 2405 if (c->u.ibpkey.low_pkey <= pkey_num && 2406 c->u.ibpkey.high_pkey >= pkey_num && 2407 c->u.ibpkey.subnet_prefix == subnet_prefix) 2408 break; 2409 2410 c = c->next; 2411 } 2412 2413 if (c) { 2414 if (!c->sid[0]) { 2415 rc = context_struct_to_sid(state, 2416 &c->context[0], 2417 &c->sid[0]); 2418 if (rc) 2419 goto out; 2420 } 2421 *out_sid = c->sid[0]; 2422 } else 2423 *out_sid = SECINITSID_UNLABELED; 2424 2425 out: 2426 read_unlock(&state->ss->policy_rwlock); 2427 return rc; 2428 } 2429 2430 /** 2431 * security_ib_endport_sid - Obtain the SID for a subnet management interface. 2432 * @dev_name: device name 2433 * @port: port number 2434 * @out_sid: security identifier 2435 */ 2436 int security_ib_endport_sid(struct selinux_state *state, 2437 const char *dev_name, u8 port_num, u32 *out_sid) 2438 { 2439 struct policydb *policydb; 2440 struct ocontext *c; 2441 int rc = 0; 2442 2443 read_lock(&state->ss->policy_rwlock); 2444 2445 policydb = &state->ss->policydb; 2446 2447 c = policydb->ocontexts[OCON_IBENDPORT]; 2448 while (c) { 2449 if (c->u.ibendport.port == port_num && 2450 !strncmp(c->u.ibendport.dev_name, 2451 dev_name, 2452 IB_DEVICE_NAME_MAX)) 2453 break; 2454 2455 c = c->next; 2456 } 2457 2458 if (c) { 2459 if (!c->sid[0]) { 2460 rc = context_struct_to_sid(state, &c->context[0], 2461 &c->sid[0]); 2462 if (rc) 2463 goto out; 2464 } 2465 *out_sid = c->sid[0]; 2466 } else 2467 *out_sid = SECINITSID_UNLABELED; 2468 2469 out: 2470 read_unlock(&state->ss->policy_rwlock); 2471 return rc; 2472 } 2473 2474 /** 2475 * security_netif_sid - Obtain the SID for a network interface. 2476 * @name: interface name 2477 * @if_sid: interface SID 2478 */ 2479 int security_netif_sid(struct selinux_state *state, 2480 char *name, u32 *if_sid) 2481 { 2482 struct policydb *policydb; 2483 int rc = 0; 2484 struct ocontext *c; 2485 2486 read_lock(&state->ss->policy_rwlock); 2487 2488 policydb = &state->ss->policydb; 2489 2490 c = policydb->ocontexts[OCON_NETIF]; 2491 while (c) { 2492 if (strcmp(name, c->u.name) == 0) 2493 break; 2494 c = c->next; 2495 } 2496 2497 if (c) { 2498 if (!c->sid[0] || !c->sid[1]) { 2499 rc = context_struct_to_sid(state, &c->context[0], 2500 &c->sid[0]); 2501 if (rc) 2502 goto out; 2503 rc = context_struct_to_sid(state, &c->context[1], 2504 &c->sid[1]); 2505 if (rc) 2506 goto out; 2507 } 2508 *if_sid = c->sid[0]; 2509 } else 2510 *if_sid = SECINITSID_NETIF; 2511 2512 out: 2513 read_unlock(&state->ss->policy_rwlock); 2514 return rc; 2515 } 2516 2517 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) 2518 { 2519 int i, fail = 0; 2520 2521 for (i = 0; i < 4; i++) 2522 if (addr[i] != (input[i] & mask[i])) { 2523 fail = 1; 2524 break; 2525 } 2526 2527 return !fail; 2528 } 2529 2530 /** 2531 * security_node_sid - Obtain the SID for a node (host). 2532 * @domain: communication domain aka address family 2533 * @addrp: address 2534 * @addrlen: address length in bytes 2535 * @out_sid: security identifier 2536 */ 2537 int security_node_sid(struct selinux_state *state, 2538 u16 domain, 2539 void *addrp, 2540 u32 addrlen, 2541 u32 *out_sid) 2542 { 2543 struct policydb *policydb; 2544 int rc; 2545 struct ocontext *c; 2546 2547 read_lock(&state->ss->policy_rwlock); 2548 2549 policydb = &state->ss->policydb; 2550 2551 switch (domain) { 2552 case AF_INET: { 2553 u32 addr; 2554 2555 rc = -EINVAL; 2556 if (addrlen != sizeof(u32)) 2557 goto out; 2558 2559 addr = *((u32 *)addrp); 2560 2561 c = policydb->ocontexts[OCON_NODE]; 2562 while (c) { 2563 if (c->u.node.addr == (addr & c->u.node.mask)) 2564 break; 2565 c = c->next; 2566 } 2567 break; 2568 } 2569 2570 case AF_INET6: 2571 rc = -EINVAL; 2572 if (addrlen != sizeof(u64) * 2) 2573 goto out; 2574 c = policydb->ocontexts[OCON_NODE6]; 2575 while (c) { 2576 if (match_ipv6_addrmask(addrp, c->u.node6.addr, 2577 c->u.node6.mask)) 2578 break; 2579 c = c->next; 2580 } 2581 break; 2582 2583 default: 2584 rc = 0; 2585 *out_sid = SECINITSID_NODE; 2586 goto out; 2587 } 2588 2589 if (c) { 2590 if (!c->sid[0]) { 2591 rc = context_struct_to_sid(state, 2592 &c->context[0], 2593 &c->sid[0]); 2594 if (rc) 2595 goto out; 2596 } 2597 *out_sid = c->sid[0]; 2598 } else { 2599 *out_sid = SECINITSID_NODE; 2600 } 2601 2602 rc = 0; 2603 out: 2604 read_unlock(&state->ss->policy_rwlock); 2605 return rc; 2606 } 2607 2608 #define SIDS_NEL 25 2609 2610 /** 2611 * security_get_user_sids - Obtain reachable SIDs for a user. 2612 * @fromsid: starting SID 2613 * @username: username 2614 * @sids: array of reachable SIDs for user 2615 * @nel: number of elements in @sids 2616 * 2617 * Generate the set of SIDs for legal security contexts 2618 * for a given user that can be reached by @fromsid. 2619 * Set *@sids to point to a dynamically allocated 2620 * array containing the set of SIDs. Set *@nel to the 2621 * number of elements in the array. 2622 */ 2623 2624 int security_get_user_sids(struct selinux_state *state, 2625 u32 fromsid, 2626 char *username, 2627 u32 **sids, 2628 u32 *nel) 2629 { 2630 struct policydb *policydb; 2631 struct sidtab *sidtab; 2632 struct context *fromcon, usercon; 2633 u32 *mysids = NULL, *mysids2, sid; 2634 u32 mynel = 0, maxnel = SIDS_NEL; 2635 struct user_datum *user; 2636 struct role_datum *role; 2637 struct ebitmap_node *rnode, *tnode; 2638 int rc = 0, i, j; 2639 2640 *sids = NULL; 2641 *nel = 0; 2642 2643 if (!selinux_initialized(state)) 2644 goto out; 2645 2646 read_lock(&state->ss->policy_rwlock); 2647 2648 policydb = &state->ss->policydb; 2649 sidtab = state->ss->sidtab; 2650 2651 context_init(&usercon); 2652 2653 rc = -EINVAL; 2654 fromcon = sidtab_search(sidtab, fromsid); 2655 if (!fromcon) 2656 goto out_unlock; 2657 2658 rc = -EINVAL; 2659 user = hashtab_search(policydb->p_users.table, username); 2660 if (!user) 2661 goto out_unlock; 2662 2663 usercon.user = user->value; 2664 2665 rc = -ENOMEM; 2666 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); 2667 if (!mysids) 2668 goto out_unlock; 2669 2670 ebitmap_for_each_positive_bit(&user->roles, rnode, i) { 2671 role = policydb->role_val_to_struct[i]; 2672 usercon.role = i + 1; 2673 ebitmap_for_each_positive_bit(&role->types, tnode, j) { 2674 usercon.type = j + 1; 2675 /* 2676 * The same context struct is reused here so the hash 2677 * must be reset. 2678 */ 2679 usercon.hash = 0; 2680 2681 if (mls_setup_user_range(policydb, fromcon, user, 2682 &usercon)) 2683 continue; 2684 2685 rc = context_struct_to_sid(state, &usercon, &sid); 2686 if (rc) 2687 goto out_unlock; 2688 if (mynel < maxnel) { 2689 mysids[mynel++] = sid; 2690 } else { 2691 rc = -ENOMEM; 2692 maxnel += SIDS_NEL; 2693 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); 2694 if (!mysids2) 2695 goto out_unlock; 2696 memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); 2697 kfree(mysids); 2698 mysids = mysids2; 2699 mysids[mynel++] = sid; 2700 } 2701 } 2702 } 2703 rc = 0; 2704 out_unlock: 2705 read_unlock(&state->ss->policy_rwlock); 2706 if (rc || !mynel) { 2707 kfree(mysids); 2708 goto out; 2709 } 2710 2711 rc = -ENOMEM; 2712 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); 2713 if (!mysids2) { 2714 kfree(mysids); 2715 goto out; 2716 } 2717 for (i = 0, j = 0; i < mynel; i++) { 2718 struct av_decision dummy_avd; 2719 rc = avc_has_perm_noaudit(state, 2720 fromsid, mysids[i], 2721 SECCLASS_PROCESS, /* kernel value */ 2722 PROCESS__TRANSITION, AVC_STRICT, 2723 &dummy_avd); 2724 if (!rc) 2725 mysids2[j++] = mysids[i]; 2726 cond_resched(); 2727 } 2728 rc = 0; 2729 kfree(mysids); 2730 *sids = mysids2; 2731 *nel = j; 2732 out: 2733 return rc; 2734 } 2735 2736 /** 2737 * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem 2738 * @fstype: filesystem type 2739 * @path: path from root of mount 2740 * @sclass: file security class 2741 * @sid: SID for path 2742 * 2743 * Obtain a SID to use for a file in a filesystem that 2744 * cannot support xattr or use a fixed labeling behavior like 2745 * transition SIDs or task SIDs. 2746 * 2747 * The caller must acquire the policy_rwlock before calling this function. 2748 */ 2749 static inline int __security_genfs_sid(struct selinux_state *state, 2750 const char *fstype, 2751 char *path, 2752 u16 orig_sclass, 2753 u32 *sid) 2754 { 2755 struct policydb *policydb = &state->ss->policydb; 2756 int len; 2757 u16 sclass; 2758 struct genfs *genfs; 2759 struct ocontext *c; 2760 int rc, cmp = 0; 2761 2762 while (path[0] == '/' && path[1] == '/') 2763 path++; 2764 2765 sclass = unmap_class(&state->ss->map, orig_sclass); 2766 *sid = SECINITSID_UNLABELED; 2767 2768 for (genfs = policydb->genfs; genfs; genfs = genfs->next) { 2769 cmp = strcmp(fstype, genfs->fstype); 2770 if (cmp <= 0) 2771 break; 2772 } 2773 2774 rc = -ENOENT; 2775 if (!genfs || cmp) 2776 goto out; 2777 2778 for (c = genfs->head; c; c = c->next) { 2779 len = strlen(c->u.name); 2780 if ((!c->v.sclass || sclass == c->v.sclass) && 2781 (strncmp(c->u.name, path, len) == 0)) 2782 break; 2783 } 2784 2785 rc = -ENOENT; 2786 if (!c) 2787 goto out; 2788 2789 if (!c->sid[0]) { 2790 rc = context_struct_to_sid(state, &c->context[0], &c->sid[0]); 2791 if (rc) 2792 goto out; 2793 } 2794 2795 *sid = c->sid[0]; 2796 rc = 0; 2797 out: 2798 return rc; 2799 } 2800 2801 /** 2802 * security_genfs_sid - Obtain a SID for a file in a filesystem 2803 * @fstype: filesystem type 2804 * @path: path from root of mount 2805 * @sclass: file security class 2806 * @sid: SID for path 2807 * 2808 * Acquire policy_rwlock before calling __security_genfs_sid() and release 2809 * it afterward. 2810 */ 2811 int security_genfs_sid(struct selinux_state *state, 2812 const char *fstype, 2813 char *path, 2814 u16 orig_sclass, 2815 u32 *sid) 2816 { 2817 int retval; 2818 2819 read_lock(&state->ss->policy_rwlock); 2820 retval = __security_genfs_sid(state, fstype, path, orig_sclass, sid); 2821 read_unlock(&state->ss->policy_rwlock); 2822 return retval; 2823 } 2824 2825 /** 2826 * security_fs_use - Determine how to handle labeling for a filesystem. 2827 * @sb: superblock in question 2828 */ 2829 int security_fs_use(struct selinux_state *state, struct super_block *sb) 2830 { 2831 struct policydb *policydb; 2832 int rc = 0; 2833 struct ocontext *c; 2834 struct superblock_security_struct *sbsec = sb->s_security; 2835 const char *fstype = sb->s_type->name; 2836 2837 read_lock(&state->ss->policy_rwlock); 2838 2839 policydb = &state->ss->policydb; 2840 2841 c = policydb->ocontexts[OCON_FSUSE]; 2842 while (c) { 2843 if (strcmp(fstype, c->u.name) == 0) 2844 break; 2845 c = c->next; 2846 } 2847 2848 if (c) { 2849 sbsec->behavior = c->v.behavior; 2850 if (!c->sid[0]) { 2851 rc = context_struct_to_sid(state, &c->context[0], 2852 &c->sid[0]); 2853 if (rc) 2854 goto out; 2855 } 2856 sbsec->sid = c->sid[0]; 2857 } else { 2858 rc = __security_genfs_sid(state, fstype, "/", SECCLASS_DIR, 2859 &sbsec->sid); 2860 if (rc) { 2861 sbsec->behavior = SECURITY_FS_USE_NONE; 2862 rc = 0; 2863 } else { 2864 sbsec->behavior = SECURITY_FS_USE_GENFS; 2865 } 2866 } 2867 2868 out: 2869 read_unlock(&state->ss->policy_rwlock); 2870 return rc; 2871 } 2872 2873 int security_get_bools(struct selinux_state *state, 2874 u32 *len, char ***names, int **values) 2875 { 2876 struct policydb *policydb; 2877 u32 i; 2878 int rc; 2879 2880 if (!selinux_initialized(state)) { 2881 *len = 0; 2882 *names = NULL; 2883 *values = NULL; 2884 return 0; 2885 } 2886 2887 read_lock(&state->ss->policy_rwlock); 2888 2889 policydb = &state->ss->policydb; 2890 2891 *names = NULL; 2892 *values = NULL; 2893 2894 rc = 0; 2895 *len = policydb->p_bools.nprim; 2896 if (!*len) 2897 goto out; 2898 2899 rc = -ENOMEM; 2900 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); 2901 if (!*names) 2902 goto err; 2903 2904 rc = -ENOMEM; 2905 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); 2906 if (!*values) 2907 goto err; 2908 2909 for (i = 0; i < *len; i++) { 2910 (*values)[i] = policydb->bool_val_to_struct[i]->state; 2911 2912 rc = -ENOMEM; 2913 (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i), 2914 GFP_ATOMIC); 2915 if (!(*names)[i]) 2916 goto err; 2917 } 2918 rc = 0; 2919 out: 2920 read_unlock(&state->ss->policy_rwlock); 2921 return rc; 2922 err: 2923 if (*names) { 2924 for (i = 0; i < *len; i++) 2925 kfree((*names)[i]); 2926 } 2927 kfree(*values); 2928 goto out; 2929 } 2930 2931 2932 int security_set_bools(struct selinux_state *state, u32 len, int *values) 2933 { 2934 struct policydb *policydb; 2935 int rc; 2936 u32 i, lenp, seqno = 0; 2937 2938 write_lock_irq(&state->ss->policy_rwlock); 2939 2940 policydb = &state->ss->policydb; 2941 2942 rc = -EFAULT; 2943 lenp = policydb->p_bools.nprim; 2944 if (len != lenp) 2945 goto out; 2946 2947 for (i = 0; i < len; i++) { 2948 if (!!values[i] != policydb->bool_val_to_struct[i]->state) { 2949 audit_log(audit_context(), GFP_ATOMIC, 2950 AUDIT_MAC_CONFIG_CHANGE, 2951 "bool=%s val=%d old_val=%d auid=%u ses=%u", 2952 sym_name(policydb, SYM_BOOLS, i), 2953 !!values[i], 2954 policydb->bool_val_to_struct[i]->state, 2955 from_kuid(&init_user_ns, audit_get_loginuid(current)), 2956 audit_get_sessionid(current)); 2957 } 2958 if (values[i]) 2959 policydb->bool_val_to_struct[i]->state = 1; 2960 else 2961 policydb->bool_val_to_struct[i]->state = 0; 2962 } 2963 2964 evaluate_cond_nodes(policydb); 2965 2966 seqno = ++state->ss->latest_granting; 2967 rc = 0; 2968 out: 2969 write_unlock_irq(&state->ss->policy_rwlock); 2970 if (!rc) { 2971 avc_ss_reset(state->avc, seqno); 2972 selnl_notify_policyload(seqno); 2973 selinux_status_update_policyload(state, seqno); 2974 selinux_xfrm_notify_policyload(); 2975 } 2976 return rc; 2977 } 2978 2979 int security_get_bool_value(struct selinux_state *state, 2980 u32 index) 2981 { 2982 struct policydb *policydb; 2983 int rc; 2984 u32 len; 2985 2986 read_lock(&state->ss->policy_rwlock); 2987 2988 policydb = &state->ss->policydb; 2989 2990 rc = -EFAULT; 2991 len = policydb->p_bools.nprim; 2992 if (index >= len) 2993 goto out; 2994 2995 rc = policydb->bool_val_to_struct[index]->state; 2996 out: 2997 read_unlock(&state->ss->policy_rwlock); 2998 return rc; 2999 } 3000 3001 static int security_preserve_bools(struct selinux_state *state, 3002 struct policydb *policydb) 3003 { 3004 int rc, *bvalues = NULL; 3005 char **bnames = NULL; 3006 struct cond_bool_datum *booldatum; 3007 u32 i, nbools = 0; 3008 3009 rc = security_get_bools(state, &nbools, &bnames, &bvalues); 3010 if (rc) 3011 goto out; 3012 for (i = 0; i < nbools; i++) { 3013 booldatum = hashtab_search(policydb->p_bools.table, bnames[i]); 3014 if (booldatum) 3015 booldatum->state = bvalues[i]; 3016 } 3017 evaluate_cond_nodes(policydb); 3018 3019 out: 3020 if (bnames) { 3021 for (i = 0; i < nbools; i++) 3022 kfree(bnames[i]); 3023 } 3024 kfree(bnames); 3025 kfree(bvalues); 3026 return rc; 3027 } 3028 3029 /* 3030 * security_sid_mls_copy() - computes a new sid based on the given 3031 * sid and the mls portion of mls_sid. 3032 */ 3033 int security_sid_mls_copy(struct selinux_state *state, 3034 u32 sid, u32 mls_sid, u32 *new_sid) 3035 { 3036 struct policydb *policydb = &state->ss->policydb; 3037 struct sidtab *sidtab = state->ss->sidtab; 3038 struct context *context1; 3039 struct context *context2; 3040 struct context newcon; 3041 char *s; 3042 u32 len; 3043 int rc; 3044 3045 rc = 0; 3046 if (!selinux_initialized(state) || !policydb->mls_enabled) { 3047 *new_sid = sid; 3048 goto out; 3049 } 3050 3051 context_init(&newcon); 3052 3053 read_lock(&state->ss->policy_rwlock); 3054 3055 rc = -EINVAL; 3056 context1 = sidtab_search(sidtab, sid); 3057 if (!context1) { 3058 pr_err("SELinux: %s: unrecognized SID %d\n", 3059 __func__, sid); 3060 goto out_unlock; 3061 } 3062 3063 rc = -EINVAL; 3064 context2 = sidtab_search(sidtab, mls_sid); 3065 if (!context2) { 3066 pr_err("SELinux: %s: unrecognized SID %d\n", 3067 __func__, mls_sid); 3068 goto out_unlock; 3069 } 3070 3071 newcon.user = context1->user; 3072 newcon.role = context1->role; 3073 newcon.type = context1->type; 3074 rc = mls_context_cpy(&newcon, context2); 3075 if (rc) 3076 goto out_unlock; 3077 3078 /* Check the validity of the new context. */ 3079 if (!policydb_context_isvalid(policydb, &newcon)) { 3080 rc = convert_context_handle_invalid_context(state, &newcon); 3081 if (rc) { 3082 if (!context_struct_to_string(policydb, &newcon, &s, 3083 &len)) { 3084 struct audit_buffer *ab; 3085 3086 ab = audit_log_start(audit_context(), 3087 GFP_ATOMIC, 3088 AUDIT_SELINUX_ERR); 3089 audit_log_format(ab, 3090 "op=security_sid_mls_copy invalid_context="); 3091 /* don't record NUL with untrusted strings */ 3092 audit_log_n_untrustedstring(ab, s, len - 1); 3093 audit_log_end(ab); 3094 kfree(s); 3095 } 3096 goto out_unlock; 3097 } 3098 } 3099 rc = context_struct_to_sid(state, &newcon, new_sid); 3100 out_unlock: 3101 read_unlock(&state->ss->policy_rwlock); 3102 context_destroy(&newcon); 3103 out: 3104 return rc; 3105 } 3106 3107 /** 3108 * security_net_peersid_resolve - Compare and resolve two network peer SIDs 3109 * @nlbl_sid: NetLabel SID 3110 * @nlbl_type: NetLabel labeling protocol type 3111 * @xfrm_sid: XFRM SID 3112 * 3113 * Description: 3114 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be 3115 * resolved into a single SID it is returned via @peer_sid and the function 3116 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function 3117 * returns a negative value. A table summarizing the behavior is below: 3118 * 3119 * | function return | @sid 3120 * ------------------------------+-----------------+----------------- 3121 * no peer labels | 0 | SECSID_NULL 3122 * single peer label | 0 | <peer_label> 3123 * multiple, consistent labels | 0 | <peer_label> 3124 * multiple, inconsistent labels | -<errno> | SECSID_NULL 3125 * 3126 */ 3127 int security_net_peersid_resolve(struct selinux_state *state, 3128 u32 nlbl_sid, u32 nlbl_type, 3129 u32 xfrm_sid, 3130 u32 *peer_sid) 3131 { 3132 struct policydb *policydb = &state->ss->policydb; 3133 struct sidtab *sidtab = state->ss->sidtab; 3134 int rc; 3135 struct context *nlbl_ctx; 3136 struct context *xfrm_ctx; 3137 3138 *peer_sid = SECSID_NULL; 3139 3140 /* handle the common (which also happens to be the set of easy) cases 3141 * right away, these two if statements catch everything involving a 3142 * single or absent peer SID/label */ 3143 if (xfrm_sid == SECSID_NULL) { 3144 *peer_sid = nlbl_sid; 3145 return 0; 3146 } 3147 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label 3148 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label 3149 * is present */ 3150 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { 3151 *peer_sid = xfrm_sid; 3152 return 0; 3153 } 3154 3155 /* 3156 * We don't need to check initialized here since the only way both 3157 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the 3158 * security server was initialized and state->initialized was true. 3159 */ 3160 if (!policydb->mls_enabled) 3161 return 0; 3162 3163 read_lock(&state->ss->policy_rwlock); 3164 3165 rc = -EINVAL; 3166 nlbl_ctx = sidtab_search(sidtab, nlbl_sid); 3167 if (!nlbl_ctx) { 3168 pr_err("SELinux: %s: unrecognized SID %d\n", 3169 __func__, nlbl_sid); 3170 goto out; 3171 } 3172 rc = -EINVAL; 3173 xfrm_ctx = sidtab_search(sidtab, xfrm_sid); 3174 if (!xfrm_ctx) { 3175 pr_err("SELinux: %s: unrecognized SID %d\n", 3176 __func__, xfrm_sid); 3177 goto out; 3178 } 3179 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); 3180 if (rc) 3181 goto out; 3182 3183 /* at present NetLabel SIDs/labels really only carry MLS 3184 * information so if the MLS portion of the NetLabel SID 3185 * matches the MLS portion of the labeled XFRM SID/label 3186 * then pass along the XFRM SID as it is the most 3187 * expressive */ 3188 *peer_sid = xfrm_sid; 3189 out: 3190 read_unlock(&state->ss->policy_rwlock); 3191 return rc; 3192 } 3193 3194 static int get_classes_callback(void *k, void *d, void *args) 3195 { 3196 struct class_datum *datum = d; 3197 char *name = k, **classes = args; 3198 int value = datum->value - 1; 3199 3200 classes[value] = kstrdup(name, GFP_ATOMIC); 3201 if (!classes[value]) 3202 return -ENOMEM; 3203 3204 return 0; 3205 } 3206 3207 int security_get_classes(struct selinux_state *state, 3208 char ***classes, int *nclasses) 3209 { 3210 struct policydb *policydb = &state->ss->policydb; 3211 int rc; 3212 3213 if (!selinux_initialized(state)) { 3214 *nclasses = 0; 3215 *classes = NULL; 3216 return 0; 3217 } 3218 3219 read_lock(&state->ss->policy_rwlock); 3220 3221 rc = -ENOMEM; 3222 *nclasses = policydb->p_classes.nprim; 3223 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); 3224 if (!*classes) 3225 goto out; 3226 3227 rc = hashtab_map(policydb->p_classes.table, get_classes_callback, 3228 *classes); 3229 if (rc) { 3230 int i; 3231 for (i = 0; i < *nclasses; i++) 3232 kfree((*classes)[i]); 3233 kfree(*classes); 3234 } 3235 3236 out: 3237 read_unlock(&state->ss->policy_rwlock); 3238 return rc; 3239 } 3240 3241 static int get_permissions_callback(void *k, void *d, void *args) 3242 { 3243 struct perm_datum *datum = d; 3244 char *name = k, **perms = args; 3245 int value = datum->value - 1; 3246 3247 perms[value] = kstrdup(name, GFP_ATOMIC); 3248 if (!perms[value]) 3249 return -ENOMEM; 3250 3251 return 0; 3252 } 3253 3254 int security_get_permissions(struct selinux_state *state, 3255 char *class, char ***perms, int *nperms) 3256 { 3257 struct policydb *policydb = &state->ss->policydb; 3258 int rc, i; 3259 struct class_datum *match; 3260 3261 read_lock(&state->ss->policy_rwlock); 3262 3263 rc = -EINVAL; 3264 match = hashtab_search(policydb->p_classes.table, class); 3265 if (!match) { 3266 pr_err("SELinux: %s: unrecognized class %s\n", 3267 __func__, class); 3268 goto out; 3269 } 3270 3271 rc = -ENOMEM; 3272 *nperms = match->permissions.nprim; 3273 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); 3274 if (!*perms) 3275 goto out; 3276 3277 if (match->comdatum) { 3278 rc = hashtab_map(match->comdatum->permissions.table, 3279 get_permissions_callback, *perms); 3280 if (rc) 3281 goto err; 3282 } 3283 3284 rc = hashtab_map(match->permissions.table, get_permissions_callback, 3285 *perms); 3286 if (rc) 3287 goto err; 3288 3289 out: 3290 read_unlock(&state->ss->policy_rwlock); 3291 return rc; 3292 3293 err: 3294 read_unlock(&state->ss->policy_rwlock); 3295 for (i = 0; i < *nperms; i++) 3296 kfree((*perms)[i]); 3297 kfree(*perms); 3298 return rc; 3299 } 3300 3301 int security_get_reject_unknown(struct selinux_state *state) 3302 { 3303 return state->ss->policydb.reject_unknown; 3304 } 3305 3306 int security_get_allow_unknown(struct selinux_state *state) 3307 { 3308 return state->ss->policydb.allow_unknown; 3309 } 3310 3311 /** 3312 * security_policycap_supported - Check for a specific policy capability 3313 * @req_cap: capability 3314 * 3315 * Description: 3316 * This function queries the currently loaded policy to see if it supports the 3317 * capability specified by @req_cap. Returns true (1) if the capability is 3318 * supported, false (0) if it isn't supported. 3319 * 3320 */ 3321 int security_policycap_supported(struct selinux_state *state, 3322 unsigned int req_cap) 3323 { 3324 struct policydb *policydb = &state->ss->policydb; 3325 int rc; 3326 3327 read_lock(&state->ss->policy_rwlock); 3328 rc = ebitmap_get_bit(&policydb->policycaps, req_cap); 3329 read_unlock(&state->ss->policy_rwlock); 3330 3331 return rc; 3332 } 3333 3334 struct selinux_audit_rule { 3335 u32 au_seqno; 3336 struct context au_ctxt; 3337 }; 3338 3339 void selinux_audit_rule_free(void *vrule) 3340 { 3341 struct selinux_audit_rule *rule = vrule; 3342 3343 if (rule) { 3344 context_destroy(&rule->au_ctxt); 3345 kfree(rule); 3346 } 3347 } 3348 3349 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 3350 { 3351 struct selinux_state *state = &selinux_state; 3352 struct policydb *policydb = &state->ss->policydb; 3353 struct selinux_audit_rule *tmprule; 3354 struct role_datum *roledatum; 3355 struct type_datum *typedatum; 3356 struct user_datum *userdatum; 3357 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; 3358 int rc = 0; 3359 3360 *rule = NULL; 3361 3362 if (!selinux_initialized(state)) 3363 return -EOPNOTSUPP; 3364 3365 switch (field) { 3366 case AUDIT_SUBJ_USER: 3367 case AUDIT_SUBJ_ROLE: 3368 case AUDIT_SUBJ_TYPE: 3369 case AUDIT_OBJ_USER: 3370 case AUDIT_OBJ_ROLE: 3371 case AUDIT_OBJ_TYPE: 3372 /* only 'equals' and 'not equals' fit user, role, and type */ 3373 if (op != Audit_equal && op != Audit_not_equal) 3374 return -EINVAL; 3375 break; 3376 case AUDIT_SUBJ_SEN: 3377 case AUDIT_SUBJ_CLR: 3378 case AUDIT_OBJ_LEV_LOW: 3379 case AUDIT_OBJ_LEV_HIGH: 3380 /* we do not allow a range, indicated by the presence of '-' */ 3381 if (strchr(rulestr, '-')) 3382 return -EINVAL; 3383 break; 3384 default: 3385 /* only the above fields are valid */ 3386 return -EINVAL; 3387 } 3388 3389 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); 3390 if (!tmprule) 3391 return -ENOMEM; 3392 3393 context_init(&tmprule->au_ctxt); 3394 3395 read_lock(&state->ss->policy_rwlock); 3396 3397 tmprule->au_seqno = state->ss->latest_granting; 3398 3399 switch (field) { 3400 case AUDIT_SUBJ_USER: 3401 case AUDIT_OBJ_USER: 3402 rc = -EINVAL; 3403 userdatum = hashtab_search(policydb->p_users.table, rulestr); 3404 if (!userdatum) 3405 goto out; 3406 tmprule->au_ctxt.user = userdatum->value; 3407 break; 3408 case AUDIT_SUBJ_ROLE: 3409 case AUDIT_OBJ_ROLE: 3410 rc = -EINVAL; 3411 roledatum = hashtab_search(policydb->p_roles.table, rulestr); 3412 if (!roledatum) 3413 goto out; 3414 tmprule->au_ctxt.role = roledatum->value; 3415 break; 3416 case AUDIT_SUBJ_TYPE: 3417 case AUDIT_OBJ_TYPE: 3418 rc = -EINVAL; 3419 typedatum = hashtab_search(policydb->p_types.table, rulestr); 3420 if (!typedatum) 3421 goto out; 3422 tmprule->au_ctxt.type = typedatum->value; 3423 break; 3424 case AUDIT_SUBJ_SEN: 3425 case AUDIT_SUBJ_CLR: 3426 case AUDIT_OBJ_LEV_LOW: 3427 case AUDIT_OBJ_LEV_HIGH: 3428 rc = mls_from_string(policydb, rulestr, &tmprule->au_ctxt, 3429 GFP_ATOMIC); 3430 if (rc) 3431 goto out; 3432 break; 3433 } 3434 rc = 0; 3435 out: 3436 read_unlock(&state->ss->policy_rwlock); 3437 3438 if (rc) { 3439 selinux_audit_rule_free(tmprule); 3440 tmprule = NULL; 3441 } 3442 3443 *rule = tmprule; 3444 3445 return rc; 3446 } 3447 3448 /* Check to see if the rule contains any selinux fields */ 3449 int selinux_audit_rule_known(struct audit_krule *rule) 3450 { 3451 int i; 3452 3453 for (i = 0; i < rule->field_count; i++) { 3454 struct audit_field *f = &rule->fields[i]; 3455 switch (f->type) { 3456 case AUDIT_SUBJ_USER: 3457 case AUDIT_SUBJ_ROLE: 3458 case AUDIT_SUBJ_TYPE: 3459 case AUDIT_SUBJ_SEN: 3460 case AUDIT_SUBJ_CLR: 3461 case AUDIT_OBJ_USER: 3462 case AUDIT_OBJ_ROLE: 3463 case AUDIT_OBJ_TYPE: 3464 case AUDIT_OBJ_LEV_LOW: 3465 case AUDIT_OBJ_LEV_HIGH: 3466 return 1; 3467 } 3468 } 3469 3470 return 0; 3471 } 3472 3473 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule) 3474 { 3475 struct selinux_state *state = &selinux_state; 3476 struct context *ctxt; 3477 struct mls_level *level; 3478 struct selinux_audit_rule *rule = vrule; 3479 int match = 0; 3480 3481 if (unlikely(!rule)) { 3482 WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n"); 3483 return -ENOENT; 3484 } 3485 3486 read_lock(&state->ss->policy_rwlock); 3487 3488 if (rule->au_seqno < state->ss->latest_granting) { 3489 match = -ESTALE; 3490 goto out; 3491 } 3492 3493 ctxt = sidtab_search(state->ss->sidtab, sid); 3494 if (unlikely(!ctxt)) { 3495 WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", 3496 sid); 3497 match = -ENOENT; 3498 goto out; 3499 } 3500 3501 /* a field/op pair that is not caught here will simply fall through 3502 without a match */ 3503 switch (field) { 3504 case AUDIT_SUBJ_USER: 3505 case AUDIT_OBJ_USER: 3506 switch (op) { 3507 case Audit_equal: 3508 match = (ctxt->user == rule->au_ctxt.user); 3509 break; 3510 case Audit_not_equal: 3511 match = (ctxt->user != rule->au_ctxt.user); 3512 break; 3513 } 3514 break; 3515 case AUDIT_SUBJ_ROLE: 3516 case AUDIT_OBJ_ROLE: 3517 switch (op) { 3518 case Audit_equal: 3519 match = (ctxt->role == rule->au_ctxt.role); 3520 break; 3521 case Audit_not_equal: 3522 match = (ctxt->role != rule->au_ctxt.role); 3523 break; 3524 } 3525 break; 3526 case AUDIT_SUBJ_TYPE: 3527 case AUDIT_OBJ_TYPE: 3528 switch (op) { 3529 case Audit_equal: 3530 match = (ctxt->type == rule->au_ctxt.type); 3531 break; 3532 case Audit_not_equal: 3533 match = (ctxt->type != rule->au_ctxt.type); 3534 break; 3535 } 3536 break; 3537 case AUDIT_SUBJ_SEN: 3538 case AUDIT_SUBJ_CLR: 3539 case AUDIT_OBJ_LEV_LOW: 3540 case AUDIT_OBJ_LEV_HIGH: 3541 level = ((field == AUDIT_SUBJ_SEN || 3542 field == AUDIT_OBJ_LEV_LOW) ? 3543 &ctxt->range.level[0] : &ctxt->range.level[1]); 3544 switch (op) { 3545 case Audit_equal: 3546 match = mls_level_eq(&rule->au_ctxt.range.level[0], 3547 level); 3548 break; 3549 case Audit_not_equal: 3550 match = !mls_level_eq(&rule->au_ctxt.range.level[0], 3551 level); 3552 break; 3553 case Audit_lt: 3554 match = (mls_level_dom(&rule->au_ctxt.range.level[0], 3555 level) && 3556 !mls_level_eq(&rule->au_ctxt.range.level[0], 3557 level)); 3558 break; 3559 case Audit_le: 3560 match = mls_level_dom(&rule->au_ctxt.range.level[0], 3561 level); 3562 break; 3563 case Audit_gt: 3564 match = (mls_level_dom(level, 3565 &rule->au_ctxt.range.level[0]) && 3566 !mls_level_eq(level, 3567 &rule->au_ctxt.range.level[0])); 3568 break; 3569 case Audit_ge: 3570 match = mls_level_dom(level, 3571 &rule->au_ctxt.range.level[0]); 3572 break; 3573 } 3574 } 3575 3576 out: 3577 read_unlock(&state->ss->policy_rwlock); 3578 return match; 3579 } 3580 3581 static int (*aurule_callback)(void) = audit_update_lsm_rules; 3582 3583 static int aurule_avc_callback(u32 event) 3584 { 3585 int err = 0; 3586 3587 if (event == AVC_CALLBACK_RESET && aurule_callback) 3588 err = aurule_callback(); 3589 return err; 3590 } 3591 3592 static int __init aurule_init(void) 3593 { 3594 int err; 3595 3596 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET); 3597 if (err) 3598 panic("avc_add_callback() failed, error %d\n", err); 3599 3600 return err; 3601 } 3602 __initcall(aurule_init); 3603 3604 #ifdef CONFIG_NETLABEL 3605 /** 3606 * security_netlbl_cache_add - Add an entry to the NetLabel cache 3607 * @secattr: the NetLabel packet security attributes 3608 * @sid: the SELinux SID 3609 * 3610 * Description: 3611 * Attempt to cache the context in @ctx, which was derived from the packet in 3612 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has 3613 * already been initialized. 3614 * 3615 */ 3616 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, 3617 u32 sid) 3618 { 3619 u32 *sid_cache; 3620 3621 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); 3622 if (sid_cache == NULL) 3623 return; 3624 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); 3625 if (secattr->cache == NULL) { 3626 kfree(sid_cache); 3627 return; 3628 } 3629 3630 *sid_cache = sid; 3631 secattr->cache->free = kfree; 3632 secattr->cache->data = sid_cache; 3633 secattr->flags |= NETLBL_SECATTR_CACHE; 3634 } 3635 3636 /** 3637 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID 3638 * @secattr: the NetLabel packet security attributes 3639 * @sid: the SELinux SID 3640 * 3641 * Description: 3642 * Convert the given NetLabel security attributes in @secattr into a 3643 * SELinux SID. If the @secattr field does not contain a full SELinux 3644 * SID/context then use SECINITSID_NETMSG as the foundation. If possible the 3645 * 'cache' field of @secattr is set and the CACHE flag is set; this is to 3646 * allow the @secattr to be used by NetLabel to cache the secattr to SID 3647 * conversion for future lookups. Returns zero on success, negative values on 3648 * failure. 3649 * 3650 */ 3651 int security_netlbl_secattr_to_sid(struct selinux_state *state, 3652 struct netlbl_lsm_secattr *secattr, 3653 u32 *sid) 3654 { 3655 struct policydb *policydb = &state->ss->policydb; 3656 struct sidtab *sidtab = state->ss->sidtab; 3657 int rc; 3658 struct context *ctx; 3659 struct context ctx_new; 3660 3661 if (!selinux_initialized(state)) { 3662 *sid = SECSID_NULL; 3663 return 0; 3664 } 3665 3666 read_lock(&state->ss->policy_rwlock); 3667 3668 if (secattr->flags & NETLBL_SECATTR_CACHE) 3669 *sid = *(u32 *)secattr->cache->data; 3670 else if (secattr->flags & NETLBL_SECATTR_SECID) 3671 *sid = secattr->attr.secid; 3672 else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { 3673 rc = -EIDRM; 3674 ctx = sidtab_search(sidtab, SECINITSID_NETMSG); 3675 if (ctx == NULL) 3676 goto out; 3677 3678 context_init(&ctx_new); 3679 ctx_new.user = ctx->user; 3680 ctx_new.role = ctx->role; 3681 ctx_new.type = ctx->type; 3682 mls_import_netlbl_lvl(policydb, &ctx_new, secattr); 3683 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { 3684 rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr); 3685 if (rc) 3686 goto out; 3687 } 3688 rc = -EIDRM; 3689 if (!mls_context_isvalid(policydb, &ctx_new)) 3690 goto out_free; 3691 3692 rc = context_struct_to_sid(state, &ctx_new, sid); 3693 if (rc) 3694 goto out_free; 3695 3696 security_netlbl_cache_add(secattr, *sid); 3697 3698 ebitmap_destroy(&ctx_new.range.level[0].cat); 3699 } else 3700 *sid = SECSID_NULL; 3701 3702 read_unlock(&state->ss->policy_rwlock); 3703 return 0; 3704 out_free: 3705 ebitmap_destroy(&ctx_new.range.level[0].cat); 3706 out: 3707 read_unlock(&state->ss->policy_rwlock); 3708 return rc; 3709 } 3710 3711 /** 3712 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr 3713 * @sid: the SELinux SID 3714 * @secattr: the NetLabel packet security attributes 3715 * 3716 * Description: 3717 * Convert the given SELinux SID in @sid into a NetLabel security attribute. 3718 * Returns zero on success, negative values on failure. 3719 * 3720 */ 3721 int security_netlbl_sid_to_secattr(struct selinux_state *state, 3722 u32 sid, struct netlbl_lsm_secattr *secattr) 3723 { 3724 struct policydb *policydb = &state->ss->policydb; 3725 int rc; 3726 struct context *ctx; 3727 3728 if (!selinux_initialized(state)) 3729 return 0; 3730 3731 read_lock(&state->ss->policy_rwlock); 3732 3733 rc = -ENOENT; 3734 ctx = sidtab_search(state->ss->sidtab, sid); 3735 if (ctx == NULL) 3736 goto out; 3737 3738 rc = -ENOMEM; 3739 secattr->domain = kstrdup(sym_name(policydb, SYM_TYPES, ctx->type - 1), 3740 GFP_ATOMIC); 3741 if (secattr->domain == NULL) 3742 goto out; 3743 3744 secattr->attr.secid = sid; 3745 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; 3746 mls_export_netlbl_lvl(policydb, ctx, secattr); 3747 rc = mls_export_netlbl_cat(policydb, ctx, secattr); 3748 out: 3749 read_unlock(&state->ss->policy_rwlock); 3750 return rc; 3751 } 3752 #endif /* CONFIG_NETLABEL */ 3753 3754 /** 3755 * security_read_policy - read the policy. 3756 * @data: binary policy data 3757 * @len: length of data in bytes 3758 * 3759 */ 3760 int security_read_policy(struct selinux_state *state, 3761 void **data, size_t *len) 3762 { 3763 struct policydb *policydb = &state->ss->policydb; 3764 int rc; 3765 struct policy_file fp; 3766 3767 if (!selinux_initialized(state)) 3768 return -EINVAL; 3769 3770 *len = security_policydb_len(state); 3771 3772 *data = vmalloc_user(*len); 3773 if (!*data) 3774 return -ENOMEM; 3775 3776 fp.data = *data; 3777 fp.len = *len; 3778 3779 read_lock(&state->ss->policy_rwlock); 3780 rc = policydb_write(policydb, &fp); 3781 read_unlock(&state->ss->policy_rwlock); 3782 3783 if (rc) 3784 return rc; 3785 3786 *len = (unsigned long)fp.data - (unsigned long)*data; 3787 return 0; 3788 3789 } 3790