services.c revision 845ca30fe9691f1bab7cfbf30b6d11c944eb4abd
1/* 2 * Implementation of the security services. 3 * 4 * Authors : Stephen Smalley, <sds@epoch.ncsc.mil> 5 * James Morris <jmorris@redhat.com> 6 * 7 * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> 8 * 9 * Support for enhanced MLS infrastructure. 10 * Support for context based audit filters. 11 * 12 * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> 13 * 14 * Added conditional policy language extensions 15 * 16 * Updated: Hewlett-Packard <paul.moore@hp.com> 17 * 18 * Added support for NetLabel 19 * Added support for the policy capability bitmap 20 * 21 * Updated: Chad Sellers <csellers@tresys.com> 22 * 23 * Added validation of kernel classes and permissions 24 * 25 * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com> 26 * 27 * Added support for bounds domain and audit messaged on masked permissions 28 * 29 * Updated: Guido Trentalancia <guido@trentalancia.com> 30 * 31 * Added support for runtime switching of the policy type 32 * 33 * Copyright (C) 2008, 2009 NEC Corporation 34 * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. 35 * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. 36 * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC 37 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> 38 * This program is free software; you can redistribute it and/or modify 39 * it under the terms of the GNU General Public License as published by 40 * the Free Software Foundation, version 2. 41 */ 42#include <linux/kernel.h> 43#include <linux/slab.h> 44#include <linux/string.h> 45#include <linux/spinlock.h> 46#include <linux/rcupdate.h> 47#include <linux/errno.h> 48#include <linux/in.h> 49#include <linux/sched.h> 50#include <linux/audit.h> 51#include <linux/mutex.h> 52#include <linux/selinux.h> 53#include <linux/flex_array.h> 54#include <net/netlabel.h> 55 56#include "flask.h" 57#include "avc.h" 58#include "avc_ss.h" 59#include "security.h" 60#include "context.h" 61#include "policydb.h" 62#include "sidtab.h" 63#include "services.h" 64#include "conditional.h" 65#include "mls.h" 66#include "objsec.h" 67#include "netlabel.h" 68#include "xfrm.h" 69#include "ebitmap.h" 70#include "audit.h" 71 72extern void selnl_notify_policyload(u32 seqno); 73 74int selinux_policycap_netpeer; 75int selinux_policycap_openperm; 76 77static DEFINE_RWLOCK(policy_rwlock); 78 79static struct sidtab sidtab; 80struct policydb policydb; 81int ss_initialized; 82 83/* 84 * The largest sequence number that has been used when 85 * providing an access decision to the access vector cache. 86 * The sequence number only changes when a policy change 87 * occurs. 88 */ 89static u32 latest_granting; 90 91/* Forward declaration. */ 92static int context_struct_to_string(struct context *context, char **scontext, 93 u32 *scontext_len); 94 95static void context_struct_compute_av(struct context *scontext, 96 struct context *tcontext, 97 u16 tclass, 98 struct av_decision *avd); 99 100struct selinux_mapping { 101 u16 value; /* policy value */ 102 unsigned num_perms; 103 u32 perms[sizeof(u32) * 8]; 104}; 105 106static struct selinux_mapping *current_mapping; 107static u16 current_mapping_size; 108 109static int selinux_set_mapping(struct policydb *pol, 110 struct security_class_mapping *map, 111 struct selinux_mapping **out_map_p, 112 u16 *out_map_size) 113{ 114 struct selinux_mapping *out_map = NULL; 115 size_t size = sizeof(struct selinux_mapping); 116 u16 i, j; 117 unsigned k; 118 bool print_unknown_handle = false; 119 120 /* Find number of classes in the input mapping */ 121 if (!map) 122 return -EINVAL; 123 i = 0; 124 while (map[i].name) 125 i++; 126 127 /* Allocate space for the class records, plus one for class zero */ 128 out_map = kcalloc(++i, size, GFP_ATOMIC); 129 if (!out_map) 130 return -ENOMEM; 131 132 /* Store the raw class and permission values */ 133 j = 0; 134 while (map[j].name) { 135 struct security_class_mapping *p_in = map + (j++); 136 struct selinux_mapping *p_out = out_map + j; 137 138 /* An empty class string skips ahead */ 139 if (!strcmp(p_in->name, "")) { 140 p_out->num_perms = 0; 141 continue; 142 } 143 144 p_out->value = string_to_security_class(pol, p_in->name); 145 if (!p_out->value) { 146 printk(KERN_INFO 147 "SELinux: Class %s not defined in policy.\n", 148 p_in->name); 149 if (pol->reject_unknown) 150 goto err; 151 p_out->num_perms = 0; 152 print_unknown_handle = true; 153 continue; 154 } 155 156 k = 0; 157 while (p_in->perms && p_in->perms[k]) { 158 /* An empty permission string skips ahead */ 159 if (!*p_in->perms[k]) { 160 k++; 161 continue; 162 } 163 p_out->perms[k] = string_to_av_perm(pol, p_out->value, 164 p_in->perms[k]); 165 if (!p_out->perms[k]) { 166 printk(KERN_INFO 167 "SELinux: Permission %s in class %s not defined in policy.\n", 168 p_in->perms[k], p_in->name); 169 if (pol->reject_unknown) 170 goto err; 171 print_unknown_handle = true; 172 } 173 174 k++; 175 } 176 p_out->num_perms = k; 177 } 178 179 if (print_unknown_handle) 180 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n", 181 pol->allow_unknown ? "allowed" : "denied"); 182 183 *out_map_p = out_map; 184 *out_map_size = i; 185 return 0; 186err: 187 kfree(out_map); 188 return -EINVAL; 189} 190 191/* 192 * Get real, policy values from mapped values 193 */ 194 195static u16 unmap_class(u16 tclass) 196{ 197 if (tclass < current_mapping_size) 198 return current_mapping[tclass].value; 199 200 return tclass; 201} 202 203static void map_decision(u16 tclass, struct av_decision *avd, 204 int allow_unknown) 205{ 206 if (tclass < current_mapping_size) { 207 unsigned i, n = current_mapping[tclass].num_perms; 208 u32 result; 209 210 for (i = 0, result = 0; i < n; i++) { 211 if (avd->allowed & current_mapping[tclass].perms[i]) 212 result |= 1<<i; 213 if (allow_unknown && !current_mapping[tclass].perms[i]) 214 result |= 1<<i; 215 } 216 avd->allowed = result; 217 218 for (i = 0, result = 0; i < n; i++) 219 if (avd->auditallow & current_mapping[tclass].perms[i]) 220 result |= 1<<i; 221 avd->auditallow = result; 222 223 for (i = 0, result = 0; i < n; i++) { 224 if (avd->auditdeny & current_mapping[tclass].perms[i]) 225 result |= 1<<i; 226 if (!allow_unknown && !current_mapping[tclass].perms[i]) 227 result |= 1<<i; 228 } 229 /* 230 * In case the kernel has a bug and requests a permission 231 * between num_perms and the maximum permission number, we 232 * should audit that denial 233 */ 234 for (; i < (sizeof(u32)*8); i++) 235 result |= 1<<i; 236 avd->auditdeny = result; 237 } 238} 239 240int security_mls_enabled(void) 241{ 242 return policydb.mls_enabled; 243} 244 245/* 246 * Return the boolean value of a constraint expression 247 * when it is applied to the specified source and target 248 * security contexts. 249 * 250 * xcontext is a special beast... It is used by the validatetrans rules 251 * only. For these rules, scontext is the context before the transition, 252 * tcontext is the context after the transition, and xcontext is the context 253 * of the process performing the transition. All other callers of 254 * constraint_expr_eval should pass in NULL for xcontext. 255 */ 256static int constraint_expr_eval(struct context *scontext, 257 struct context *tcontext, 258 struct context *xcontext, 259 struct constraint_expr *cexpr) 260{ 261 u32 val1, val2; 262 struct context *c; 263 struct role_datum *r1, *r2; 264 struct mls_level *l1, *l2; 265 struct constraint_expr *e; 266 int s[CEXPR_MAXDEPTH]; 267 int sp = -1; 268 269 for (e = cexpr; e; e = e->next) { 270 switch (e->expr_type) { 271 case CEXPR_NOT: 272 BUG_ON(sp < 0); 273 s[sp] = !s[sp]; 274 break; 275 case CEXPR_AND: 276 BUG_ON(sp < 1); 277 sp--; 278 s[sp] &= s[sp + 1]; 279 break; 280 case CEXPR_OR: 281 BUG_ON(sp < 1); 282 sp--; 283 s[sp] |= s[sp + 1]; 284 break; 285 case CEXPR_ATTR: 286 if (sp == (CEXPR_MAXDEPTH - 1)) 287 return 0; 288 switch (e->attr) { 289 case CEXPR_USER: 290 val1 = scontext->user; 291 val2 = tcontext->user; 292 break; 293 case CEXPR_TYPE: 294 val1 = scontext->type; 295 val2 = tcontext->type; 296 break; 297 case CEXPR_ROLE: 298 val1 = scontext->role; 299 val2 = tcontext->role; 300 r1 = policydb.role_val_to_struct[val1 - 1]; 301 r2 = policydb.role_val_to_struct[val2 - 1]; 302 switch (e->op) { 303 case CEXPR_DOM: 304 s[++sp] = ebitmap_get_bit(&r1->dominates, 305 val2 - 1); 306 continue; 307 case CEXPR_DOMBY: 308 s[++sp] = ebitmap_get_bit(&r2->dominates, 309 val1 - 1); 310 continue; 311 case CEXPR_INCOMP: 312 s[++sp] = (!ebitmap_get_bit(&r1->dominates, 313 val2 - 1) && 314 !ebitmap_get_bit(&r2->dominates, 315 val1 - 1)); 316 continue; 317 default: 318 break; 319 } 320 break; 321 case CEXPR_L1L2: 322 l1 = &(scontext->range.level[0]); 323 l2 = &(tcontext->range.level[0]); 324 goto mls_ops; 325 case CEXPR_L1H2: 326 l1 = &(scontext->range.level[0]); 327 l2 = &(tcontext->range.level[1]); 328 goto mls_ops; 329 case CEXPR_H1L2: 330 l1 = &(scontext->range.level[1]); 331 l2 = &(tcontext->range.level[0]); 332 goto mls_ops; 333 case CEXPR_H1H2: 334 l1 = &(scontext->range.level[1]); 335 l2 = &(tcontext->range.level[1]); 336 goto mls_ops; 337 case CEXPR_L1H1: 338 l1 = &(scontext->range.level[0]); 339 l2 = &(scontext->range.level[1]); 340 goto mls_ops; 341 case CEXPR_L2H2: 342 l1 = &(tcontext->range.level[0]); 343 l2 = &(tcontext->range.level[1]); 344 goto mls_ops; 345mls_ops: 346 switch (e->op) { 347 case CEXPR_EQ: 348 s[++sp] = mls_level_eq(l1, l2); 349 continue; 350 case CEXPR_NEQ: 351 s[++sp] = !mls_level_eq(l1, l2); 352 continue; 353 case CEXPR_DOM: 354 s[++sp] = mls_level_dom(l1, l2); 355 continue; 356 case CEXPR_DOMBY: 357 s[++sp] = mls_level_dom(l2, l1); 358 continue; 359 case CEXPR_INCOMP: 360 s[++sp] = mls_level_incomp(l2, l1); 361 continue; 362 default: 363 BUG(); 364 return 0; 365 } 366 break; 367 default: 368 BUG(); 369 return 0; 370 } 371 372 switch (e->op) { 373 case CEXPR_EQ: 374 s[++sp] = (val1 == val2); 375 break; 376 case CEXPR_NEQ: 377 s[++sp] = (val1 != val2); 378 break; 379 default: 380 BUG(); 381 return 0; 382 } 383 break; 384 case CEXPR_NAMES: 385 if (sp == (CEXPR_MAXDEPTH-1)) 386 return 0; 387 c = scontext; 388 if (e->attr & CEXPR_TARGET) 389 c = tcontext; 390 else if (e->attr & CEXPR_XTARGET) { 391 c = xcontext; 392 if (!c) { 393 BUG(); 394 return 0; 395 } 396 } 397 if (e->attr & CEXPR_USER) 398 val1 = c->user; 399 else if (e->attr & CEXPR_ROLE) 400 val1 = c->role; 401 else if (e->attr & CEXPR_TYPE) 402 val1 = c->type; 403 else { 404 BUG(); 405 return 0; 406 } 407 408 switch (e->op) { 409 case CEXPR_EQ: 410 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); 411 break; 412 case CEXPR_NEQ: 413 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); 414 break; 415 default: 416 BUG(); 417 return 0; 418 } 419 break; 420 default: 421 BUG(); 422 return 0; 423 } 424 } 425 426 BUG_ON(sp != 0); 427 return s[0]; 428} 429 430/* 431 * security_dump_masked_av - dumps masked permissions during 432 * security_compute_av due to RBAC, MLS/Constraint and Type bounds. 433 */ 434static int dump_masked_av_helper(void *k, void *d, void *args) 435{ 436 struct perm_datum *pdatum = d; 437 char **permission_names = args; 438 439 BUG_ON(pdatum->value < 1 || pdatum->value > 32); 440 441 permission_names[pdatum->value - 1] = (char *)k; 442 443 return 0; 444} 445 446static void security_dump_masked_av(struct context *scontext, 447 struct context *tcontext, 448 u16 tclass, 449 u32 permissions, 450 const char *reason) 451{ 452 struct common_datum *common_dat; 453 struct class_datum *tclass_dat; 454 struct audit_buffer *ab; 455 char *tclass_name; 456 char *scontext_name = NULL; 457 char *tcontext_name = NULL; 458 char *permission_names[32]; 459 int index; 460 u32 length; 461 bool need_comma = false; 462 463 if (!permissions) 464 return; 465 466 tclass_name = policydb.p_class_val_to_name[tclass - 1]; 467 tclass_dat = policydb.class_val_to_struct[tclass - 1]; 468 common_dat = tclass_dat->comdatum; 469 470 /* init permission_names */ 471 if (common_dat && 472 hashtab_map(common_dat->permissions.table, 473 dump_masked_av_helper, permission_names) < 0) 474 goto out; 475 476 if (hashtab_map(tclass_dat->permissions.table, 477 dump_masked_av_helper, permission_names) < 0) 478 goto out; 479 480 /* get scontext/tcontext in text form */ 481 if (context_struct_to_string(scontext, 482 &scontext_name, &length) < 0) 483 goto out; 484 485 if (context_struct_to_string(tcontext, 486 &tcontext_name, &length) < 0) 487 goto out; 488 489 /* audit a message */ 490 ab = audit_log_start(current->audit_context, 491 GFP_ATOMIC, AUDIT_SELINUX_ERR); 492 if (!ab) 493 goto out; 494 495 audit_log_format(ab, "op=security_compute_av reason=%s " 496 "scontext=%s tcontext=%s tclass=%s perms=", 497 reason, scontext_name, tcontext_name, tclass_name); 498 499 for (index = 0; index < 32; index++) { 500 u32 mask = (1 << index); 501 502 if ((mask & permissions) == 0) 503 continue; 504 505 audit_log_format(ab, "%s%s", 506 need_comma ? "," : "", 507 permission_names[index] 508 ? permission_names[index] : "????"); 509 need_comma = true; 510 } 511 audit_log_end(ab); 512out: 513 /* release scontext/tcontext */ 514 kfree(tcontext_name); 515 kfree(scontext_name); 516 517 return; 518} 519 520/* 521 * security_boundary_permission - drops violated permissions 522 * on boundary constraint. 523 */ 524static void type_attribute_bounds_av(struct context *scontext, 525 struct context *tcontext, 526 u16 tclass, 527 struct av_decision *avd) 528{ 529 struct context lo_scontext; 530 struct context lo_tcontext; 531 struct av_decision lo_avd; 532 struct type_datum *source 533 = policydb.type_val_to_struct[scontext->type - 1]; 534 struct type_datum *target 535 = policydb.type_val_to_struct[tcontext->type - 1]; 536 u32 masked = 0; 537 538 if (source->bounds) { 539 memset(&lo_avd, 0, sizeof(lo_avd)); 540 541 memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); 542 lo_scontext.type = source->bounds; 543 544 context_struct_compute_av(&lo_scontext, 545 tcontext, 546 tclass, 547 &lo_avd); 548 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 549 return; /* no masked permission */ 550 masked = ~lo_avd.allowed & avd->allowed; 551 } 552 553 if (target->bounds) { 554 memset(&lo_avd, 0, sizeof(lo_avd)); 555 556 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); 557 lo_tcontext.type = target->bounds; 558 559 context_struct_compute_av(scontext, 560 &lo_tcontext, 561 tclass, 562 &lo_avd); 563 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 564 return; /* no masked permission */ 565 masked = ~lo_avd.allowed & avd->allowed; 566 } 567 568 if (source->bounds && target->bounds) { 569 memset(&lo_avd, 0, sizeof(lo_avd)); 570 /* 571 * lo_scontext and lo_tcontext are already 572 * set up. 573 */ 574 575 context_struct_compute_av(&lo_scontext, 576 &lo_tcontext, 577 tclass, 578 &lo_avd); 579 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 580 return; /* no masked permission */ 581 masked = ~lo_avd.allowed & avd->allowed; 582 } 583 584 if (masked) { 585 /* mask violated permissions */ 586 avd->allowed &= ~masked; 587 588 /* audit masked permissions */ 589 security_dump_masked_av(scontext, tcontext, 590 tclass, masked, "bounds"); 591 } 592} 593 594/* 595 * Compute access vectors based on a context structure pair for 596 * the permissions in a particular class. 597 */ 598static void context_struct_compute_av(struct context *scontext, 599 struct context *tcontext, 600 u16 tclass, 601 struct av_decision *avd) 602{ 603 struct constraint_node *constraint; 604 struct role_allow *ra; 605 struct avtab_key avkey; 606 struct avtab_node *node; 607 struct class_datum *tclass_datum; 608 struct ebitmap *sattr, *tattr; 609 struct ebitmap_node *snode, *tnode; 610 unsigned int i, j; 611 612 avd->allowed = 0; 613 avd->auditallow = 0; 614 avd->auditdeny = 0xffffffff; 615 616 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { 617 if (printk_ratelimit()) 618 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); 619 return; 620 } 621 622 tclass_datum = policydb.class_val_to_struct[tclass - 1]; 623 624 /* 625 * If a specific type enforcement rule was defined for 626 * this permission check, then use it. 627 */ 628 avkey.target_class = tclass; 629 avkey.specified = AVTAB_AV; 630 sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1); 631 BUG_ON(!sattr); 632 tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1); 633 BUG_ON(!tattr); 634 ebitmap_for_each_positive_bit(sattr, snode, i) { 635 ebitmap_for_each_positive_bit(tattr, tnode, j) { 636 avkey.source_type = i + 1; 637 avkey.target_type = j + 1; 638 for (node = avtab_search_node(&policydb.te_avtab, &avkey); 639 node; 640 node = avtab_search_node_next(node, avkey.specified)) { 641 if (node->key.specified == AVTAB_ALLOWED) 642 avd->allowed |= node->datum.data; 643 else if (node->key.specified == AVTAB_AUDITALLOW) 644 avd->auditallow |= node->datum.data; 645 else if (node->key.specified == AVTAB_AUDITDENY) 646 avd->auditdeny &= node->datum.data; 647 } 648 649 /* Check conditional av table for additional permissions */ 650 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); 651 652 } 653 } 654 655 /* 656 * Remove any permissions prohibited by a constraint (this includes 657 * the MLS policy). 658 */ 659 constraint = tclass_datum->constraints; 660 while (constraint) { 661 if ((constraint->permissions & (avd->allowed)) && 662 !constraint_expr_eval(scontext, tcontext, NULL, 663 constraint->expr)) { 664 avd->allowed &= ~(constraint->permissions); 665 } 666 constraint = constraint->next; 667 } 668 669 /* 670 * If checking process transition permission and the 671 * role is changing, then check the (current_role, new_role) 672 * pair. 673 */ 674 if (tclass == policydb.process_class && 675 (avd->allowed & policydb.process_trans_perms) && 676 scontext->role != tcontext->role) { 677 for (ra = policydb.role_allow; ra; ra = ra->next) { 678 if (scontext->role == ra->role && 679 tcontext->role == ra->new_role) 680 break; 681 } 682 if (!ra) 683 avd->allowed &= ~policydb.process_trans_perms; 684 } 685 686 /* 687 * If the given source and target types have boundary 688 * constraint, lazy checks have to mask any violated 689 * permission and notice it to userspace via audit. 690 */ 691 type_attribute_bounds_av(scontext, tcontext, 692 tclass, avd); 693} 694 695static int security_validtrans_handle_fail(struct context *ocontext, 696 struct context *ncontext, 697 struct context *tcontext, 698 u16 tclass) 699{ 700 char *o = NULL, *n = NULL, *t = NULL; 701 u32 olen, nlen, tlen; 702 703 if (context_struct_to_string(ocontext, &o, &olen) < 0) 704 goto out; 705 if (context_struct_to_string(ncontext, &n, &nlen) < 0) 706 goto out; 707 if (context_struct_to_string(tcontext, &t, &tlen) < 0) 708 goto out; 709 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 710 "security_validate_transition: denied for" 711 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", 712 o, n, t, policydb.p_class_val_to_name[tclass-1]); 713out: 714 kfree(o); 715 kfree(n); 716 kfree(t); 717 718 if (!selinux_enforcing) 719 return 0; 720 return -EPERM; 721} 722 723int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, 724 u16 orig_tclass) 725{ 726 struct context *ocontext; 727 struct context *ncontext; 728 struct context *tcontext; 729 struct class_datum *tclass_datum; 730 struct constraint_node *constraint; 731 u16 tclass; 732 int rc = 0; 733 734 if (!ss_initialized) 735 return 0; 736 737 read_lock(&policy_rwlock); 738 739 tclass = unmap_class(orig_tclass); 740 741 if (!tclass || tclass > policydb.p_classes.nprim) { 742 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n", 743 __func__, tclass); 744 rc = -EINVAL; 745 goto out; 746 } 747 tclass_datum = policydb.class_val_to_struct[tclass - 1]; 748 749 ocontext = sidtab_search(&sidtab, oldsid); 750 if (!ocontext) { 751 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 752 __func__, oldsid); 753 rc = -EINVAL; 754 goto out; 755 } 756 757 ncontext = sidtab_search(&sidtab, newsid); 758 if (!ncontext) { 759 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 760 __func__, newsid); 761 rc = -EINVAL; 762 goto out; 763 } 764 765 tcontext = sidtab_search(&sidtab, tasksid); 766 if (!tcontext) { 767 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 768 __func__, tasksid); 769 rc = -EINVAL; 770 goto out; 771 } 772 773 constraint = tclass_datum->validatetrans; 774 while (constraint) { 775 if (!constraint_expr_eval(ocontext, ncontext, tcontext, 776 constraint->expr)) { 777 rc = security_validtrans_handle_fail(ocontext, ncontext, 778 tcontext, tclass); 779 goto out; 780 } 781 constraint = constraint->next; 782 } 783 784out: 785 read_unlock(&policy_rwlock); 786 return rc; 787} 788 789/* 790 * security_bounded_transition - check whether the given 791 * transition is directed to bounded, or not. 792 * It returns 0, if @newsid is bounded by @oldsid. 793 * Otherwise, it returns error code. 794 * 795 * @oldsid : current security identifier 796 * @newsid : destinated security identifier 797 */ 798int security_bounded_transition(u32 old_sid, u32 new_sid) 799{ 800 struct context *old_context, *new_context; 801 struct type_datum *type; 802 int index; 803 int rc = -EINVAL; 804 805 read_lock(&policy_rwlock); 806 807 old_context = sidtab_search(&sidtab, old_sid); 808 if (!old_context) { 809 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 810 __func__, old_sid); 811 goto out; 812 } 813 814 new_context = sidtab_search(&sidtab, new_sid); 815 if (!new_context) { 816 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 817 __func__, new_sid); 818 goto out; 819 } 820 821 /* type/domain unchanged */ 822 if (old_context->type == new_context->type) { 823 rc = 0; 824 goto out; 825 } 826 827 index = new_context->type; 828 while (true) { 829 type = policydb.type_val_to_struct[index - 1]; 830 BUG_ON(!type); 831 832 /* not bounded anymore */ 833 if (!type->bounds) { 834 rc = -EPERM; 835 break; 836 } 837 838 /* @newsid is bounded by @oldsid */ 839 if (type->bounds == old_context->type) { 840 rc = 0; 841 break; 842 } 843 index = type->bounds; 844 } 845 846 if (rc) { 847 char *old_name = NULL; 848 char *new_name = NULL; 849 u32 length; 850 851 if (!context_struct_to_string(old_context, 852 &old_name, &length) && 853 !context_struct_to_string(new_context, 854 &new_name, &length)) { 855 audit_log(current->audit_context, 856 GFP_ATOMIC, AUDIT_SELINUX_ERR, 857 "op=security_bounded_transition " 858 "result=denied " 859 "oldcontext=%s newcontext=%s", 860 old_name, new_name); 861 } 862 kfree(new_name); 863 kfree(old_name); 864 } 865out: 866 read_unlock(&policy_rwlock); 867 868 return rc; 869} 870 871static void avd_init(struct av_decision *avd) 872{ 873 avd->allowed = 0; 874 avd->auditallow = 0; 875 avd->auditdeny = 0xffffffff; 876 avd->seqno = latest_granting; 877 avd->flags = 0; 878} 879 880 881/** 882 * security_compute_av - Compute access vector decisions. 883 * @ssid: source security identifier 884 * @tsid: target security identifier 885 * @tclass: target security class 886 * @avd: access vector decisions 887 * 888 * Compute a set of access vector decisions based on the 889 * SID pair (@ssid, @tsid) for the permissions in @tclass. 890 */ 891void security_compute_av(u32 ssid, 892 u32 tsid, 893 u16 orig_tclass, 894 struct av_decision *avd) 895{ 896 u16 tclass; 897 struct context *scontext = NULL, *tcontext = NULL; 898 899 read_lock(&policy_rwlock); 900 avd_init(avd); 901 if (!ss_initialized) 902 goto allow; 903 904 scontext = sidtab_search(&sidtab, ssid); 905 if (!scontext) { 906 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 907 __func__, ssid); 908 goto out; 909 } 910 911 /* permissive domain? */ 912 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) 913 avd->flags |= AVD_FLAGS_PERMISSIVE; 914 915 tcontext = sidtab_search(&sidtab, tsid); 916 if (!tcontext) { 917 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 918 __func__, tsid); 919 goto out; 920 } 921 922 tclass = unmap_class(orig_tclass); 923 if (unlikely(orig_tclass && !tclass)) { 924 if (policydb.allow_unknown) 925 goto allow; 926 goto out; 927 } 928 context_struct_compute_av(scontext, tcontext, tclass, avd); 929 map_decision(orig_tclass, avd, policydb.allow_unknown); 930out: 931 read_unlock(&policy_rwlock); 932 return; 933allow: 934 avd->allowed = 0xffffffff; 935 goto out; 936} 937 938void security_compute_av_user(u32 ssid, 939 u32 tsid, 940 u16 tclass, 941 struct av_decision *avd) 942{ 943 struct context *scontext = NULL, *tcontext = NULL; 944 945 read_lock(&policy_rwlock); 946 avd_init(avd); 947 if (!ss_initialized) 948 goto allow; 949 950 scontext = sidtab_search(&sidtab, ssid); 951 if (!scontext) { 952 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 953 __func__, ssid); 954 goto out; 955 } 956 957 /* permissive domain? */ 958 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) 959 avd->flags |= AVD_FLAGS_PERMISSIVE; 960 961 tcontext = sidtab_search(&sidtab, tsid); 962 if (!tcontext) { 963 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 964 __func__, tsid); 965 goto out; 966 } 967 968 if (unlikely(!tclass)) { 969 if (policydb.allow_unknown) 970 goto allow; 971 goto out; 972 } 973 974 context_struct_compute_av(scontext, tcontext, tclass, avd); 975 out: 976 read_unlock(&policy_rwlock); 977 return; 978allow: 979 avd->allowed = 0xffffffff; 980 goto out; 981} 982 983/* 984 * Write the security context string representation of 985 * the context structure `context' into a dynamically 986 * allocated string of the correct size. Set `*scontext' 987 * to point to this string and set `*scontext_len' to 988 * the length of the string. 989 */ 990static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len) 991{ 992 char *scontextp; 993 994 if (scontext) 995 *scontext = NULL; 996 *scontext_len = 0; 997 998 if (context->len) { 999 *scontext_len = context->len; 1000 *scontext = kstrdup(context->str, GFP_ATOMIC); 1001 if (!(*scontext)) 1002 return -ENOMEM; 1003 return 0; 1004 } 1005 1006 /* Compute the size of the context. */ 1007 *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1; 1008 *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1; 1009 *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1; 1010 *scontext_len += mls_compute_context_len(context); 1011 1012 if (!scontext) 1013 return 0; 1014 1015 /* Allocate space for the context; caller must free this space. */ 1016 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1017 if (!scontextp) 1018 return -ENOMEM; 1019 *scontext = scontextp; 1020 1021 /* 1022 * Copy the user name, role name and type name into the context. 1023 */ 1024 sprintf(scontextp, "%s:%s:%s", 1025 policydb.p_user_val_to_name[context->user - 1], 1026 policydb.p_role_val_to_name[context->role - 1], 1027 policydb.p_type_val_to_name[context->type - 1]); 1028 scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1029 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) + 1030 1 + strlen(policydb.p_type_val_to_name[context->type - 1]); 1031 1032 mls_sid_to_context(context, &scontextp); 1033 1034 *scontextp = 0; 1035 1036 return 0; 1037} 1038 1039#include "initial_sid_to_string.h" 1040 1041const char *security_get_initial_sid_context(u32 sid) 1042{ 1043 if (unlikely(sid > SECINITSID_NUM)) 1044 return NULL; 1045 return initial_sid_to_string[sid]; 1046} 1047 1048static int security_sid_to_context_core(u32 sid, char **scontext, 1049 u32 *scontext_len, int force) 1050{ 1051 struct context *context; 1052 int rc = 0; 1053 1054 if (scontext) 1055 *scontext = NULL; 1056 *scontext_len = 0; 1057 1058 if (!ss_initialized) { 1059 if (sid <= SECINITSID_NUM) { 1060 char *scontextp; 1061 1062 *scontext_len = strlen(initial_sid_to_string[sid]) + 1; 1063 if (!scontext) 1064 goto out; 1065 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1066 if (!scontextp) { 1067 rc = -ENOMEM; 1068 goto out; 1069 } 1070 strcpy(scontextp, initial_sid_to_string[sid]); 1071 *scontext = scontextp; 1072 goto out; 1073 } 1074 printk(KERN_ERR "SELinux: %s: called before initial " 1075 "load_policy on unknown SID %d\n", __func__, sid); 1076 rc = -EINVAL; 1077 goto out; 1078 } 1079 read_lock(&policy_rwlock); 1080 if (force) 1081 context = sidtab_search_force(&sidtab, sid); 1082 else 1083 context = sidtab_search(&sidtab, sid); 1084 if (!context) { 1085 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1086 __func__, sid); 1087 rc = -EINVAL; 1088 goto out_unlock; 1089 } 1090 rc = context_struct_to_string(context, scontext, scontext_len); 1091out_unlock: 1092 read_unlock(&policy_rwlock); 1093out: 1094 return rc; 1095 1096} 1097 1098/** 1099 * security_sid_to_context - Obtain a context for a given SID. 1100 * @sid: security identifier, SID 1101 * @scontext: security context 1102 * @scontext_len: length in bytes 1103 * 1104 * Write the string representation of the context associated with @sid 1105 * into a dynamically allocated string of the correct size. Set @scontext 1106 * to point to this string and set @scontext_len to the length of the string. 1107 */ 1108int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) 1109{ 1110 return security_sid_to_context_core(sid, scontext, scontext_len, 0); 1111} 1112 1113int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len) 1114{ 1115 return security_sid_to_context_core(sid, scontext, scontext_len, 1); 1116} 1117 1118/* 1119 * Caveat: Mutates scontext. 1120 */ 1121static int string_to_context_struct(struct policydb *pol, 1122 struct sidtab *sidtabp, 1123 char *scontext, 1124 u32 scontext_len, 1125 struct context *ctx, 1126 u32 def_sid) 1127{ 1128 struct role_datum *role; 1129 struct type_datum *typdatum; 1130 struct user_datum *usrdatum; 1131 char *scontextp, *p, oldc; 1132 int rc = 0; 1133 1134 context_init(ctx); 1135 1136 /* Parse the security context. */ 1137 1138 rc = -EINVAL; 1139 scontextp = (char *) scontext; 1140 1141 /* Extract the user. */ 1142 p = scontextp; 1143 while (*p && *p != ':') 1144 p++; 1145 1146 if (*p == 0) 1147 goto out; 1148 1149 *p++ = 0; 1150 1151 usrdatum = hashtab_search(pol->p_users.table, scontextp); 1152 if (!usrdatum) 1153 goto out; 1154 1155 ctx->user = usrdatum->value; 1156 1157 /* Extract role. */ 1158 scontextp = p; 1159 while (*p && *p != ':') 1160 p++; 1161 1162 if (*p == 0) 1163 goto out; 1164 1165 *p++ = 0; 1166 1167 role = hashtab_search(pol->p_roles.table, scontextp); 1168 if (!role) 1169 goto out; 1170 ctx->role = role->value; 1171 1172 /* Extract type. */ 1173 scontextp = p; 1174 while (*p && *p != ':') 1175 p++; 1176 oldc = *p; 1177 *p++ = 0; 1178 1179 typdatum = hashtab_search(pol->p_types.table, scontextp); 1180 if (!typdatum || typdatum->attribute) 1181 goto out; 1182 1183 ctx->type = typdatum->value; 1184 1185 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid); 1186 if (rc) 1187 goto out; 1188 1189 if ((p - scontext) < scontext_len) { 1190 rc = -EINVAL; 1191 goto out; 1192 } 1193 1194 /* Check the validity of the new context. */ 1195 if (!policydb_context_isvalid(pol, ctx)) { 1196 rc = -EINVAL; 1197 goto out; 1198 } 1199 rc = 0; 1200out: 1201 if (rc) 1202 context_destroy(ctx); 1203 return rc; 1204} 1205 1206static int security_context_to_sid_core(const char *scontext, u32 scontext_len, 1207 u32 *sid, u32 def_sid, gfp_t gfp_flags, 1208 int force) 1209{ 1210 char *scontext2, *str = NULL; 1211 struct context context; 1212 int rc = 0; 1213 1214 if (!ss_initialized) { 1215 int i; 1216 1217 for (i = 1; i < SECINITSID_NUM; i++) { 1218 if (!strcmp(initial_sid_to_string[i], scontext)) { 1219 *sid = i; 1220 return 0; 1221 } 1222 } 1223 *sid = SECINITSID_KERNEL; 1224 return 0; 1225 } 1226 *sid = SECSID_NULL; 1227 1228 /* Copy the string so that we can modify the copy as we parse it. */ 1229 scontext2 = kmalloc(scontext_len + 1, gfp_flags); 1230 if (!scontext2) 1231 return -ENOMEM; 1232 memcpy(scontext2, scontext, scontext_len); 1233 scontext2[scontext_len] = 0; 1234 1235 if (force) { 1236 /* Save another copy for storing in uninterpreted form */ 1237 str = kstrdup(scontext2, gfp_flags); 1238 if (!str) { 1239 kfree(scontext2); 1240 return -ENOMEM; 1241 } 1242 } 1243 1244 read_lock(&policy_rwlock); 1245 rc = string_to_context_struct(&policydb, &sidtab, 1246 scontext2, scontext_len, 1247 &context, def_sid); 1248 if (rc == -EINVAL && force) { 1249 context.str = str; 1250 context.len = scontext_len; 1251 str = NULL; 1252 } else if (rc) 1253 goto out; 1254 rc = sidtab_context_to_sid(&sidtab, &context, sid); 1255 context_destroy(&context); 1256out: 1257 read_unlock(&policy_rwlock); 1258 kfree(scontext2); 1259 kfree(str); 1260 return rc; 1261} 1262 1263/** 1264 * security_context_to_sid - Obtain a SID for a given security context. 1265 * @scontext: security context 1266 * @scontext_len: length in bytes 1267 * @sid: security identifier, SID 1268 * 1269 * Obtains a SID associated with the security context that 1270 * has the string representation specified by @scontext. 1271 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1272 * memory is available, or 0 on success. 1273 */ 1274int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid) 1275{ 1276 return security_context_to_sid_core(scontext, scontext_len, 1277 sid, SECSID_NULL, GFP_KERNEL, 0); 1278} 1279 1280/** 1281 * security_context_to_sid_default - Obtain a SID for a given security context, 1282 * falling back to specified default if needed. 1283 * 1284 * @scontext: security context 1285 * @scontext_len: length in bytes 1286 * @sid: security identifier, SID 1287 * @def_sid: default SID to assign on error 1288 * 1289 * Obtains a SID associated with the security context that 1290 * has the string representation specified by @scontext. 1291 * The default SID is passed to the MLS layer to be used to allow 1292 * kernel labeling of the MLS field if the MLS field is not present 1293 * (for upgrading to MLS without full relabel). 1294 * Implicitly forces adding of the context even if it cannot be mapped yet. 1295 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1296 * memory is available, or 0 on success. 1297 */ 1298int security_context_to_sid_default(const char *scontext, u32 scontext_len, 1299 u32 *sid, u32 def_sid, gfp_t gfp_flags) 1300{ 1301 return security_context_to_sid_core(scontext, scontext_len, 1302 sid, def_sid, gfp_flags, 1); 1303} 1304 1305int security_context_to_sid_force(const char *scontext, u32 scontext_len, 1306 u32 *sid) 1307{ 1308 return security_context_to_sid_core(scontext, scontext_len, 1309 sid, SECSID_NULL, GFP_KERNEL, 1); 1310} 1311 1312static int compute_sid_handle_invalid_context( 1313 struct context *scontext, 1314 struct context *tcontext, 1315 u16 tclass, 1316 struct context *newcontext) 1317{ 1318 char *s = NULL, *t = NULL, *n = NULL; 1319 u32 slen, tlen, nlen; 1320 1321 if (context_struct_to_string(scontext, &s, &slen) < 0) 1322 goto out; 1323 if (context_struct_to_string(tcontext, &t, &tlen) < 0) 1324 goto out; 1325 if (context_struct_to_string(newcontext, &n, &nlen) < 0) 1326 goto out; 1327 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 1328 "security_compute_sid: invalid context %s" 1329 " for scontext=%s" 1330 " tcontext=%s" 1331 " tclass=%s", 1332 n, s, t, policydb.p_class_val_to_name[tclass-1]); 1333out: 1334 kfree(s); 1335 kfree(t); 1336 kfree(n); 1337 if (!selinux_enforcing) 1338 return 0; 1339 return -EACCES; 1340} 1341 1342static int security_compute_sid(u32 ssid, 1343 u32 tsid, 1344 u16 orig_tclass, 1345 u32 specified, 1346 u32 *out_sid, 1347 bool kern) 1348{ 1349 struct context *scontext = NULL, *tcontext = NULL, newcontext; 1350 struct role_trans *roletr = NULL; 1351 struct avtab_key avkey; 1352 struct avtab_datum *avdatum; 1353 struct avtab_node *node; 1354 u16 tclass; 1355 int rc = 0; 1356 1357 if (!ss_initialized) { 1358 switch (orig_tclass) { 1359 case SECCLASS_PROCESS: /* kernel value */ 1360 *out_sid = ssid; 1361 break; 1362 default: 1363 *out_sid = tsid; 1364 break; 1365 } 1366 goto out; 1367 } 1368 1369 context_init(&newcontext); 1370 1371 read_lock(&policy_rwlock); 1372 1373 if (kern) 1374 tclass = unmap_class(orig_tclass); 1375 else 1376 tclass = orig_tclass; 1377 1378 scontext = sidtab_search(&sidtab, ssid); 1379 if (!scontext) { 1380 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1381 __func__, ssid); 1382 rc = -EINVAL; 1383 goto out_unlock; 1384 } 1385 tcontext = sidtab_search(&sidtab, tsid); 1386 if (!tcontext) { 1387 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1388 __func__, tsid); 1389 rc = -EINVAL; 1390 goto out_unlock; 1391 } 1392 1393 /* Set the user identity. */ 1394 switch (specified) { 1395 case AVTAB_TRANSITION: 1396 case AVTAB_CHANGE: 1397 /* Use the process user identity. */ 1398 newcontext.user = scontext->user; 1399 break; 1400 case AVTAB_MEMBER: 1401 /* Use the related object owner. */ 1402 newcontext.user = tcontext->user; 1403 break; 1404 } 1405 1406 /* Set the role and type to default values. */ 1407 if (tclass == policydb.process_class) { 1408 /* Use the current role and type of process. */ 1409 newcontext.role = scontext->role; 1410 newcontext.type = scontext->type; 1411 } else { 1412 /* Use the well-defined object role. */ 1413 newcontext.role = OBJECT_R_VAL; 1414 /* Use the type of the related object. */ 1415 newcontext.type = tcontext->type; 1416 } 1417 1418 /* Look for a type transition/member/change rule. */ 1419 avkey.source_type = scontext->type; 1420 avkey.target_type = tcontext->type; 1421 avkey.target_class = tclass; 1422 avkey.specified = specified; 1423 avdatum = avtab_search(&policydb.te_avtab, &avkey); 1424 1425 /* If no permanent rule, also check for enabled conditional rules */ 1426 if (!avdatum) { 1427 node = avtab_search_node(&policydb.te_cond_avtab, &avkey); 1428 for (; node; node = avtab_search_node_next(node, specified)) { 1429 if (node->key.specified & AVTAB_ENABLED) { 1430 avdatum = &node->datum; 1431 break; 1432 } 1433 } 1434 } 1435 1436 if (avdatum) { 1437 /* Use the type from the type transition/member/change rule. */ 1438 newcontext.type = avdatum->data; 1439 } 1440 1441 /* Check for class-specific changes. */ 1442 if (tclass == policydb.process_class) { 1443 if (specified & AVTAB_TRANSITION) { 1444 /* Look for a role transition rule. */ 1445 for (roletr = policydb.role_tr; roletr; 1446 roletr = roletr->next) { 1447 if (roletr->role == scontext->role && 1448 roletr->type == tcontext->type) { 1449 /* Use the role transition rule. */ 1450 newcontext.role = roletr->new_role; 1451 break; 1452 } 1453 } 1454 } 1455 } 1456 1457 /* Set the MLS attributes. 1458 This is done last because it may allocate memory. */ 1459 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext); 1460 if (rc) 1461 goto out_unlock; 1462 1463 /* Check the validity of the context. */ 1464 if (!policydb_context_isvalid(&policydb, &newcontext)) { 1465 rc = compute_sid_handle_invalid_context(scontext, 1466 tcontext, 1467 tclass, 1468 &newcontext); 1469 if (rc) 1470 goto out_unlock; 1471 } 1472 /* Obtain the sid for the context. */ 1473 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid); 1474out_unlock: 1475 read_unlock(&policy_rwlock); 1476 context_destroy(&newcontext); 1477out: 1478 return rc; 1479} 1480 1481/** 1482 * security_transition_sid - Compute the SID for a new subject/object. 1483 * @ssid: source security identifier 1484 * @tsid: target security identifier 1485 * @tclass: target security class 1486 * @out_sid: security identifier for new subject/object 1487 * 1488 * Compute a SID to use for labeling a new subject or object in the 1489 * class @tclass based on a SID pair (@ssid, @tsid). 1490 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1491 * if insufficient memory is available, or %0 if the new SID was 1492 * computed successfully. 1493 */ 1494int security_transition_sid(u32 ssid, 1495 u32 tsid, 1496 u16 tclass, 1497 u32 *out_sid) 1498{ 1499 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, 1500 out_sid, true); 1501} 1502 1503int security_transition_sid_user(u32 ssid, 1504 u32 tsid, 1505 u16 tclass, 1506 u32 *out_sid) 1507{ 1508 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, 1509 out_sid, false); 1510} 1511 1512/** 1513 * security_member_sid - Compute the SID for member selection. 1514 * @ssid: source security identifier 1515 * @tsid: target security identifier 1516 * @tclass: target security class 1517 * @out_sid: security identifier for selected member 1518 * 1519 * Compute a SID to use when selecting a member of a polyinstantiated 1520 * object of class @tclass based on a SID pair (@ssid, @tsid). 1521 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1522 * if insufficient memory is available, or %0 if the SID was 1523 * computed successfully. 1524 */ 1525int security_member_sid(u32 ssid, 1526 u32 tsid, 1527 u16 tclass, 1528 u32 *out_sid) 1529{ 1530 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid, 1531 false); 1532} 1533 1534/** 1535 * security_change_sid - Compute the SID for object relabeling. 1536 * @ssid: source security identifier 1537 * @tsid: target security identifier 1538 * @tclass: target security class 1539 * @out_sid: security identifier for selected member 1540 * 1541 * Compute a SID to use for relabeling an object of class @tclass 1542 * based on a SID pair (@ssid, @tsid). 1543 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1544 * if insufficient memory is available, or %0 if the SID was 1545 * computed successfully. 1546 */ 1547int security_change_sid(u32 ssid, 1548 u32 tsid, 1549 u16 tclass, 1550 u32 *out_sid) 1551{ 1552 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid, 1553 false); 1554} 1555 1556/* Clone the SID into the new SID table. */ 1557static int clone_sid(u32 sid, 1558 struct context *context, 1559 void *arg) 1560{ 1561 struct sidtab *s = arg; 1562 1563 if (sid > SECINITSID_NUM) 1564 return sidtab_insert(s, sid, context); 1565 else 1566 return 0; 1567} 1568 1569static inline int convert_context_handle_invalid_context(struct context *context) 1570{ 1571 int rc = 0; 1572 1573 if (selinux_enforcing) { 1574 rc = -EINVAL; 1575 } else { 1576 char *s; 1577 u32 len; 1578 1579 if (!context_struct_to_string(context, &s, &len)) { 1580 printk(KERN_WARNING 1581 "SELinux: Context %s would be invalid if enforcing\n", 1582 s); 1583 kfree(s); 1584 } 1585 } 1586 return rc; 1587} 1588 1589struct convert_context_args { 1590 struct policydb *oldp; 1591 struct policydb *newp; 1592}; 1593 1594/* 1595 * Convert the values in the security context 1596 * structure `c' from the values specified 1597 * in the policy `p->oldp' to the values specified 1598 * in the policy `p->newp'. Verify that the 1599 * context is valid under the new policy. 1600 */ 1601static int convert_context(u32 key, 1602 struct context *c, 1603 void *p) 1604{ 1605 struct convert_context_args *args; 1606 struct context oldc; 1607 struct ocontext *oc; 1608 struct mls_range *range; 1609 struct role_datum *role; 1610 struct type_datum *typdatum; 1611 struct user_datum *usrdatum; 1612 char *s; 1613 u32 len; 1614 int rc = 0; 1615 1616 if (key <= SECINITSID_NUM) 1617 goto out; 1618 1619 args = p; 1620 1621 if (c->str) { 1622 struct context ctx; 1623 s = kstrdup(c->str, GFP_KERNEL); 1624 if (!s) { 1625 rc = -ENOMEM; 1626 goto out; 1627 } 1628 rc = string_to_context_struct(args->newp, NULL, s, 1629 c->len, &ctx, SECSID_NULL); 1630 kfree(s); 1631 if (!rc) { 1632 printk(KERN_INFO 1633 "SELinux: Context %s became valid (mapped).\n", 1634 c->str); 1635 /* Replace string with mapped representation. */ 1636 kfree(c->str); 1637 memcpy(c, &ctx, sizeof(*c)); 1638 goto out; 1639 } else if (rc == -EINVAL) { 1640 /* Retain string representation for later mapping. */ 1641 rc = 0; 1642 goto out; 1643 } else { 1644 /* Other error condition, e.g. ENOMEM. */ 1645 printk(KERN_ERR 1646 "SELinux: Unable to map context %s, rc = %d.\n", 1647 c->str, -rc); 1648 goto out; 1649 } 1650 } 1651 1652 rc = context_cpy(&oldc, c); 1653 if (rc) 1654 goto out; 1655 1656 rc = -EINVAL; 1657 1658 /* Convert the user. */ 1659 usrdatum = hashtab_search(args->newp->p_users.table, 1660 args->oldp->p_user_val_to_name[c->user - 1]); 1661 if (!usrdatum) 1662 goto bad; 1663 c->user = usrdatum->value; 1664 1665 /* Convert the role. */ 1666 role = hashtab_search(args->newp->p_roles.table, 1667 args->oldp->p_role_val_to_name[c->role - 1]); 1668 if (!role) 1669 goto bad; 1670 c->role = role->value; 1671 1672 /* Convert the type. */ 1673 typdatum = hashtab_search(args->newp->p_types.table, 1674 args->oldp->p_type_val_to_name[c->type - 1]); 1675 if (!typdatum) 1676 goto bad; 1677 c->type = typdatum->value; 1678 1679 /* Convert the MLS fields if dealing with MLS policies */ 1680 if (args->oldp->mls_enabled && args->newp->mls_enabled) { 1681 rc = mls_convert_context(args->oldp, args->newp, c); 1682 if (rc) 1683 goto bad; 1684 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { 1685 /* 1686 * Switching between MLS and non-MLS policy: 1687 * free any storage used by the MLS fields in the 1688 * context for all existing entries in the sidtab. 1689 */ 1690 mls_context_destroy(c); 1691 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { 1692 /* 1693 * Switching between non-MLS and MLS policy: 1694 * ensure that the MLS fields of the context for all 1695 * existing entries in the sidtab are filled in with a 1696 * suitable default value, likely taken from one of the 1697 * initial SIDs. 1698 */ 1699 oc = args->newp->ocontexts[OCON_ISID]; 1700 while (oc && oc->sid[0] != SECINITSID_UNLABELED) 1701 oc = oc->next; 1702 if (!oc) { 1703 printk(KERN_ERR "SELinux: unable to look up" 1704 " the initial SIDs list\n"); 1705 goto bad; 1706 } 1707 range = &oc->context[0].range; 1708 rc = mls_range_set(c, range); 1709 if (rc) 1710 goto bad; 1711 } 1712 1713 /* Check the validity of the new context. */ 1714 if (!policydb_context_isvalid(args->newp, c)) { 1715 rc = convert_context_handle_invalid_context(&oldc); 1716 if (rc) 1717 goto bad; 1718 } 1719 1720 context_destroy(&oldc); 1721 rc = 0; 1722out: 1723 return rc; 1724bad: 1725 /* Map old representation to string and save it. */ 1726 if (context_struct_to_string(&oldc, &s, &len)) 1727 return -ENOMEM; 1728 context_destroy(&oldc); 1729 context_destroy(c); 1730 c->str = s; 1731 c->len = len; 1732 printk(KERN_INFO 1733 "SELinux: Context %s became invalid (unmapped).\n", 1734 c->str); 1735 rc = 0; 1736 goto out; 1737} 1738 1739static void security_load_policycaps(void) 1740{ 1741 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps, 1742 POLICYDB_CAPABILITY_NETPEER); 1743 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps, 1744 POLICYDB_CAPABILITY_OPENPERM); 1745} 1746 1747extern void selinux_complete_init(void); 1748static int security_preserve_bools(struct policydb *p); 1749 1750/** 1751 * security_load_policy - Load a security policy configuration. 1752 * @data: binary policy data 1753 * @len: length of data in bytes 1754 * 1755 * Load a new set of security policy configuration data, 1756 * validate it and convert the SID table as necessary. 1757 * This function will flush the access vector cache after 1758 * loading the new policy. 1759 */ 1760int security_load_policy(void *data, size_t len) 1761{ 1762 struct policydb oldpolicydb, newpolicydb; 1763 struct sidtab oldsidtab, newsidtab; 1764 struct selinux_mapping *oldmap, *map = NULL; 1765 struct convert_context_args args; 1766 u32 seqno; 1767 u16 map_size; 1768 int rc = 0; 1769 struct policy_file file = { data, len }, *fp = &file; 1770 1771 if (!ss_initialized) { 1772 avtab_cache_init(); 1773 rc = policydb_read(&policydb, fp); 1774 if (rc) { 1775 avtab_cache_destroy(); 1776 return rc; 1777 } 1778 1779 policydb.len = len; 1780 rc = selinux_set_mapping(&policydb, secclass_map, 1781 ¤t_mapping, 1782 ¤t_mapping_size); 1783 if (rc) { 1784 policydb_destroy(&policydb); 1785 avtab_cache_destroy(); 1786 return rc; 1787 } 1788 1789 rc = policydb_load_isids(&policydb, &sidtab); 1790 if (rc) { 1791 policydb_destroy(&policydb); 1792 avtab_cache_destroy(); 1793 return rc; 1794 } 1795 1796 security_load_policycaps(); 1797 ss_initialized = 1; 1798 seqno = ++latest_granting; 1799 selinux_complete_init(); 1800 avc_ss_reset(seqno); 1801 selnl_notify_policyload(seqno); 1802 selinux_status_update_policyload(seqno); 1803 selinux_netlbl_cache_invalidate(); 1804 selinux_xfrm_notify_policyload(); 1805 return 0; 1806 } 1807 1808#if 0 1809 sidtab_hash_eval(&sidtab, "sids"); 1810#endif 1811 1812 rc = policydb_read(&newpolicydb, fp); 1813 if (rc) 1814 return rc; 1815 1816 newpolicydb.len = len; 1817 /* If switching between different policy types, log MLS status */ 1818 if (policydb.mls_enabled && !newpolicydb.mls_enabled) 1819 printk(KERN_INFO "SELinux: Disabling MLS support...\n"); 1820 else if (!policydb.mls_enabled && newpolicydb.mls_enabled) 1821 printk(KERN_INFO "SELinux: Enabling MLS support...\n"); 1822 1823 rc = policydb_load_isids(&newpolicydb, &newsidtab); 1824 if (rc) { 1825 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); 1826 policydb_destroy(&newpolicydb); 1827 return rc; 1828 } 1829 1830 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size); 1831 if (rc) 1832 goto err; 1833 1834 rc = security_preserve_bools(&newpolicydb); 1835 if (rc) { 1836 printk(KERN_ERR "SELinux: unable to preserve booleans\n"); 1837 goto err; 1838 } 1839 1840 /* Clone the SID table. */ 1841 sidtab_shutdown(&sidtab); 1842 1843 rc = sidtab_map(&sidtab, clone_sid, &newsidtab); 1844 if (rc) 1845 goto err; 1846 1847 /* 1848 * Convert the internal representations of contexts 1849 * in the new SID table. 1850 */ 1851 args.oldp = &policydb; 1852 args.newp = &newpolicydb; 1853 rc = sidtab_map(&newsidtab, convert_context, &args); 1854 if (rc) { 1855 printk(KERN_ERR "SELinux: unable to convert the internal" 1856 " representation of contexts in the new SID" 1857 " table\n"); 1858 goto err; 1859 } 1860 1861 /* Save the old policydb and SID table to free later. */ 1862 memcpy(&oldpolicydb, &policydb, sizeof policydb); 1863 sidtab_set(&oldsidtab, &sidtab); 1864 1865 /* Install the new policydb and SID table. */ 1866 write_lock_irq(&policy_rwlock); 1867 memcpy(&policydb, &newpolicydb, sizeof policydb); 1868 sidtab_set(&sidtab, &newsidtab); 1869 security_load_policycaps(); 1870 oldmap = current_mapping; 1871 current_mapping = map; 1872 current_mapping_size = map_size; 1873 seqno = ++latest_granting; 1874 write_unlock_irq(&policy_rwlock); 1875 1876 /* Free the old policydb and SID table. */ 1877 policydb_destroy(&oldpolicydb); 1878 sidtab_destroy(&oldsidtab); 1879 kfree(oldmap); 1880 1881 avc_ss_reset(seqno); 1882 selnl_notify_policyload(seqno); 1883 selinux_status_update_policyload(seqno); 1884 selinux_netlbl_cache_invalidate(); 1885 selinux_xfrm_notify_policyload(); 1886 1887 return 0; 1888 1889err: 1890 kfree(map); 1891 sidtab_destroy(&newsidtab); 1892 policydb_destroy(&newpolicydb); 1893 return rc; 1894 1895} 1896 1897size_t security_policydb_len(void) 1898{ 1899 size_t len; 1900 1901 read_lock(&policy_rwlock); 1902 len = policydb.len; 1903 read_unlock(&policy_rwlock); 1904 1905 return len; 1906} 1907 1908/** 1909 * security_port_sid - Obtain the SID for a port. 1910 * @protocol: protocol number 1911 * @port: port number 1912 * @out_sid: security identifier 1913 */ 1914int security_port_sid(u8 protocol, u16 port, u32 *out_sid) 1915{ 1916 struct ocontext *c; 1917 int rc = 0; 1918 1919 read_lock(&policy_rwlock); 1920 1921 c = policydb.ocontexts[OCON_PORT]; 1922 while (c) { 1923 if (c->u.port.protocol == protocol && 1924 c->u.port.low_port <= port && 1925 c->u.port.high_port >= port) 1926 break; 1927 c = c->next; 1928 } 1929 1930 if (c) { 1931 if (!c->sid[0]) { 1932 rc = sidtab_context_to_sid(&sidtab, 1933 &c->context[0], 1934 &c->sid[0]); 1935 if (rc) 1936 goto out; 1937 } 1938 *out_sid = c->sid[0]; 1939 } else { 1940 *out_sid = SECINITSID_PORT; 1941 } 1942 1943out: 1944 read_unlock(&policy_rwlock); 1945 return rc; 1946} 1947 1948/** 1949 * security_netif_sid - Obtain the SID for a network interface. 1950 * @name: interface name 1951 * @if_sid: interface SID 1952 */ 1953int security_netif_sid(char *name, u32 *if_sid) 1954{ 1955 int rc = 0; 1956 struct ocontext *c; 1957 1958 read_lock(&policy_rwlock); 1959 1960 c = policydb.ocontexts[OCON_NETIF]; 1961 while (c) { 1962 if (strcmp(name, c->u.name) == 0) 1963 break; 1964 c = c->next; 1965 } 1966 1967 if (c) { 1968 if (!c->sid[0] || !c->sid[1]) { 1969 rc = sidtab_context_to_sid(&sidtab, 1970 &c->context[0], 1971 &c->sid[0]); 1972 if (rc) 1973 goto out; 1974 rc = sidtab_context_to_sid(&sidtab, 1975 &c->context[1], 1976 &c->sid[1]); 1977 if (rc) 1978 goto out; 1979 } 1980 *if_sid = c->sid[0]; 1981 } else 1982 *if_sid = SECINITSID_NETIF; 1983 1984out: 1985 read_unlock(&policy_rwlock); 1986 return rc; 1987} 1988 1989static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) 1990{ 1991 int i, fail = 0; 1992 1993 for (i = 0; i < 4; i++) 1994 if (addr[i] != (input[i] & mask[i])) { 1995 fail = 1; 1996 break; 1997 } 1998 1999 return !fail; 2000} 2001 2002/** 2003 * security_node_sid - Obtain the SID for a node (host). 2004 * @domain: communication domain aka address family 2005 * @addrp: address 2006 * @addrlen: address length in bytes 2007 * @out_sid: security identifier 2008 */ 2009int security_node_sid(u16 domain, 2010 void *addrp, 2011 u32 addrlen, 2012 u32 *out_sid) 2013{ 2014 int rc = 0; 2015 struct ocontext *c; 2016 2017 read_lock(&policy_rwlock); 2018 2019 switch (domain) { 2020 case AF_INET: { 2021 u32 addr; 2022 2023 if (addrlen != sizeof(u32)) { 2024 rc = -EINVAL; 2025 goto out; 2026 } 2027 2028 addr = *((u32 *)addrp); 2029 2030 c = policydb.ocontexts[OCON_NODE]; 2031 while (c) { 2032 if (c->u.node.addr == (addr & c->u.node.mask)) 2033 break; 2034 c = c->next; 2035 } 2036 break; 2037 } 2038 2039 case AF_INET6: 2040 if (addrlen != sizeof(u64) * 2) { 2041 rc = -EINVAL; 2042 goto out; 2043 } 2044 c = policydb.ocontexts[OCON_NODE6]; 2045 while (c) { 2046 if (match_ipv6_addrmask(addrp, c->u.node6.addr, 2047 c->u.node6.mask)) 2048 break; 2049 c = c->next; 2050 } 2051 break; 2052 2053 default: 2054 *out_sid = SECINITSID_NODE; 2055 goto out; 2056 } 2057 2058 if (c) { 2059 if (!c->sid[0]) { 2060 rc = sidtab_context_to_sid(&sidtab, 2061 &c->context[0], 2062 &c->sid[0]); 2063 if (rc) 2064 goto out; 2065 } 2066 *out_sid = c->sid[0]; 2067 } else { 2068 *out_sid = SECINITSID_NODE; 2069 } 2070 2071out: 2072 read_unlock(&policy_rwlock); 2073 return rc; 2074} 2075 2076#define SIDS_NEL 25 2077 2078/** 2079 * security_get_user_sids - Obtain reachable SIDs for a user. 2080 * @fromsid: starting SID 2081 * @username: username 2082 * @sids: array of reachable SIDs for user 2083 * @nel: number of elements in @sids 2084 * 2085 * Generate the set of SIDs for legal security contexts 2086 * for a given user that can be reached by @fromsid. 2087 * Set *@sids to point to a dynamically allocated 2088 * array containing the set of SIDs. Set *@nel to the 2089 * number of elements in the array. 2090 */ 2091 2092int security_get_user_sids(u32 fromsid, 2093 char *username, 2094 u32 **sids, 2095 u32 *nel) 2096{ 2097 struct context *fromcon, usercon; 2098 u32 *mysids = NULL, *mysids2, sid; 2099 u32 mynel = 0, maxnel = SIDS_NEL; 2100 struct user_datum *user; 2101 struct role_datum *role; 2102 struct ebitmap_node *rnode, *tnode; 2103 int rc = 0, i, j; 2104 2105 *sids = NULL; 2106 *nel = 0; 2107 2108 if (!ss_initialized) 2109 goto out; 2110 2111 read_lock(&policy_rwlock); 2112 2113 context_init(&usercon); 2114 2115 fromcon = sidtab_search(&sidtab, fromsid); 2116 if (!fromcon) { 2117 rc = -EINVAL; 2118 goto out_unlock; 2119 } 2120 2121 user = hashtab_search(policydb.p_users.table, username); 2122 if (!user) { 2123 rc = -EINVAL; 2124 goto out_unlock; 2125 } 2126 usercon.user = user->value; 2127 2128 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); 2129 if (!mysids) { 2130 rc = -ENOMEM; 2131 goto out_unlock; 2132 } 2133 2134 ebitmap_for_each_positive_bit(&user->roles, rnode, i) { 2135 role = policydb.role_val_to_struct[i]; 2136 usercon.role = i + 1; 2137 ebitmap_for_each_positive_bit(&role->types, tnode, j) { 2138 usercon.type = j + 1; 2139 2140 if (mls_setup_user_range(fromcon, user, &usercon)) 2141 continue; 2142 2143 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); 2144 if (rc) 2145 goto out_unlock; 2146 if (mynel < maxnel) { 2147 mysids[mynel++] = sid; 2148 } else { 2149 maxnel += SIDS_NEL; 2150 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); 2151 if (!mysids2) { 2152 rc = -ENOMEM; 2153 goto out_unlock; 2154 } 2155 memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); 2156 kfree(mysids); 2157 mysids = mysids2; 2158 mysids[mynel++] = sid; 2159 } 2160 } 2161 } 2162 2163out_unlock: 2164 read_unlock(&policy_rwlock); 2165 if (rc || !mynel) { 2166 kfree(mysids); 2167 goto out; 2168 } 2169 2170 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); 2171 if (!mysids2) { 2172 rc = -ENOMEM; 2173 kfree(mysids); 2174 goto out; 2175 } 2176 for (i = 0, j = 0; i < mynel; i++) { 2177 rc = avc_has_perm_noaudit(fromsid, mysids[i], 2178 SECCLASS_PROCESS, /* kernel value */ 2179 PROCESS__TRANSITION, AVC_STRICT, 2180 NULL); 2181 if (!rc) 2182 mysids2[j++] = mysids[i]; 2183 cond_resched(); 2184 } 2185 rc = 0; 2186 kfree(mysids); 2187 *sids = mysids2; 2188 *nel = j; 2189out: 2190 return rc; 2191} 2192 2193/** 2194 * security_genfs_sid - Obtain a SID for a file in a filesystem 2195 * @fstype: filesystem type 2196 * @path: path from root of mount 2197 * @sclass: file security class 2198 * @sid: SID for path 2199 * 2200 * Obtain a SID to use for a file in a filesystem that 2201 * cannot support xattr or use a fixed labeling behavior like 2202 * transition SIDs or task SIDs. 2203 */ 2204int security_genfs_sid(const char *fstype, 2205 char *path, 2206 u16 orig_sclass, 2207 u32 *sid) 2208{ 2209 int len; 2210 u16 sclass; 2211 struct genfs *genfs; 2212 struct ocontext *c; 2213 int rc = 0, cmp = 0; 2214 2215 while (path[0] == '/' && path[1] == '/') 2216 path++; 2217 2218 read_lock(&policy_rwlock); 2219 2220 sclass = unmap_class(orig_sclass); 2221 2222 for (genfs = policydb.genfs; genfs; genfs = genfs->next) { 2223 cmp = strcmp(fstype, genfs->fstype); 2224 if (cmp <= 0) 2225 break; 2226 } 2227 2228 if (!genfs || cmp) { 2229 *sid = SECINITSID_UNLABELED; 2230 rc = -ENOENT; 2231 goto out; 2232 } 2233 2234 for (c = genfs->head; c; c = c->next) { 2235 len = strlen(c->u.name); 2236 if ((!c->v.sclass || sclass == c->v.sclass) && 2237 (strncmp(c->u.name, path, len) == 0)) 2238 break; 2239 } 2240 2241 if (!c) { 2242 *sid = SECINITSID_UNLABELED; 2243 rc = -ENOENT; 2244 goto out; 2245 } 2246 2247 if (!c->sid[0]) { 2248 rc = sidtab_context_to_sid(&sidtab, 2249 &c->context[0], 2250 &c->sid[0]); 2251 if (rc) 2252 goto out; 2253 } 2254 2255 *sid = c->sid[0]; 2256out: 2257 read_unlock(&policy_rwlock); 2258 return rc; 2259} 2260 2261/** 2262 * security_fs_use - Determine how to handle labeling for a filesystem. 2263 * @fstype: filesystem type 2264 * @behavior: labeling behavior 2265 * @sid: SID for filesystem (superblock) 2266 */ 2267int security_fs_use( 2268 const char *fstype, 2269 unsigned int *behavior, 2270 u32 *sid) 2271{ 2272 int rc = 0; 2273 struct ocontext *c; 2274 2275 read_lock(&policy_rwlock); 2276 2277 c = policydb.ocontexts[OCON_FSUSE]; 2278 while (c) { 2279 if (strcmp(fstype, c->u.name) == 0) 2280 break; 2281 c = c->next; 2282 } 2283 2284 if (c) { 2285 *behavior = c->v.behavior; 2286 if (!c->sid[0]) { 2287 rc = sidtab_context_to_sid(&sidtab, 2288 &c->context[0], 2289 &c->sid[0]); 2290 if (rc) 2291 goto out; 2292 } 2293 *sid = c->sid[0]; 2294 } else { 2295 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid); 2296 if (rc) { 2297 *behavior = SECURITY_FS_USE_NONE; 2298 rc = 0; 2299 } else { 2300 *behavior = SECURITY_FS_USE_GENFS; 2301 } 2302 } 2303 2304out: 2305 read_unlock(&policy_rwlock); 2306 return rc; 2307} 2308 2309int security_get_bools(int *len, char ***names, int **values) 2310{ 2311 int i, rc = -ENOMEM; 2312 2313 read_lock(&policy_rwlock); 2314 *names = NULL; 2315 *values = NULL; 2316 2317 *len = policydb.p_bools.nprim; 2318 if (!*len) { 2319 rc = 0; 2320 goto out; 2321 } 2322 2323 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); 2324 if (!*names) 2325 goto err; 2326 2327 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); 2328 if (!*values) 2329 goto err; 2330 2331 for (i = 0; i < *len; i++) { 2332 size_t name_len; 2333 (*values)[i] = policydb.bool_val_to_struct[i]->state; 2334 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1; 2335 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC); 2336 if (!(*names)[i]) 2337 goto err; 2338 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len); 2339 (*names)[i][name_len - 1] = 0; 2340 } 2341 rc = 0; 2342out: 2343 read_unlock(&policy_rwlock); 2344 return rc; 2345err: 2346 if (*names) { 2347 for (i = 0; i < *len; i++) 2348 kfree((*names)[i]); 2349 } 2350 kfree(*values); 2351 goto out; 2352} 2353 2354 2355int security_set_bools(int len, int *values) 2356{ 2357 int i, rc = 0; 2358 int lenp, seqno = 0; 2359 struct cond_node *cur; 2360 2361 write_lock_irq(&policy_rwlock); 2362 2363 lenp = policydb.p_bools.nprim; 2364 if (len != lenp) { 2365 rc = -EFAULT; 2366 goto out; 2367 } 2368 2369 for (i = 0; i < len; i++) { 2370 if (!!values[i] != policydb.bool_val_to_struct[i]->state) { 2371 audit_log(current->audit_context, GFP_ATOMIC, 2372 AUDIT_MAC_CONFIG_CHANGE, 2373 "bool=%s val=%d old_val=%d auid=%u ses=%u", 2374 policydb.p_bool_val_to_name[i], 2375 !!values[i], 2376 policydb.bool_val_to_struct[i]->state, 2377 audit_get_loginuid(current), 2378 audit_get_sessionid(current)); 2379 } 2380 if (values[i]) 2381 policydb.bool_val_to_struct[i]->state = 1; 2382 else 2383 policydb.bool_val_to_struct[i]->state = 0; 2384 } 2385 2386 for (cur = policydb.cond_list; cur; cur = cur->next) { 2387 rc = evaluate_cond_node(&policydb, cur); 2388 if (rc) 2389 goto out; 2390 } 2391 2392 seqno = ++latest_granting; 2393 2394out: 2395 write_unlock_irq(&policy_rwlock); 2396 if (!rc) { 2397 avc_ss_reset(seqno); 2398 selnl_notify_policyload(seqno); 2399 selinux_status_update_policyload(seqno); 2400 selinux_xfrm_notify_policyload(); 2401 } 2402 return rc; 2403} 2404 2405int security_get_bool_value(int bool) 2406{ 2407 int rc = 0; 2408 int len; 2409 2410 read_lock(&policy_rwlock); 2411 2412 len = policydb.p_bools.nprim; 2413 if (bool >= len) { 2414 rc = -EFAULT; 2415 goto out; 2416 } 2417 2418 rc = policydb.bool_val_to_struct[bool]->state; 2419out: 2420 read_unlock(&policy_rwlock); 2421 return rc; 2422} 2423 2424static int security_preserve_bools(struct policydb *p) 2425{ 2426 int rc, nbools = 0, *bvalues = NULL, i; 2427 char **bnames = NULL; 2428 struct cond_bool_datum *booldatum; 2429 struct cond_node *cur; 2430 2431 rc = security_get_bools(&nbools, &bnames, &bvalues); 2432 if (rc) 2433 goto out; 2434 for (i = 0; i < nbools; i++) { 2435 booldatum = hashtab_search(p->p_bools.table, bnames[i]); 2436 if (booldatum) 2437 booldatum->state = bvalues[i]; 2438 } 2439 for (cur = p->cond_list; cur; cur = cur->next) { 2440 rc = evaluate_cond_node(p, cur); 2441 if (rc) 2442 goto out; 2443 } 2444 2445out: 2446 if (bnames) { 2447 for (i = 0; i < nbools; i++) 2448 kfree(bnames[i]); 2449 } 2450 kfree(bnames); 2451 kfree(bvalues); 2452 return rc; 2453} 2454 2455/* 2456 * security_sid_mls_copy() - computes a new sid based on the given 2457 * sid and the mls portion of mls_sid. 2458 */ 2459int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid) 2460{ 2461 struct context *context1; 2462 struct context *context2; 2463 struct context newcon; 2464 char *s; 2465 u32 len; 2466 int rc = 0; 2467 2468 if (!ss_initialized || !policydb.mls_enabled) { 2469 *new_sid = sid; 2470 goto out; 2471 } 2472 2473 context_init(&newcon); 2474 2475 read_lock(&policy_rwlock); 2476 context1 = sidtab_search(&sidtab, sid); 2477 if (!context1) { 2478 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2479 __func__, sid); 2480 rc = -EINVAL; 2481 goto out_unlock; 2482 } 2483 2484 context2 = sidtab_search(&sidtab, mls_sid); 2485 if (!context2) { 2486 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2487 __func__, mls_sid); 2488 rc = -EINVAL; 2489 goto out_unlock; 2490 } 2491 2492 newcon.user = context1->user; 2493 newcon.role = context1->role; 2494 newcon.type = context1->type; 2495 rc = mls_context_cpy(&newcon, context2); 2496 if (rc) 2497 goto out_unlock; 2498 2499 /* Check the validity of the new context. */ 2500 if (!policydb_context_isvalid(&policydb, &newcon)) { 2501 rc = convert_context_handle_invalid_context(&newcon); 2502 if (rc) 2503 goto bad; 2504 } 2505 2506 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid); 2507 goto out_unlock; 2508 2509bad: 2510 if (!context_struct_to_string(&newcon, &s, &len)) { 2511 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2512 "security_sid_mls_copy: invalid context %s", s); 2513 kfree(s); 2514 } 2515 2516out_unlock: 2517 read_unlock(&policy_rwlock); 2518 context_destroy(&newcon); 2519out: 2520 return rc; 2521} 2522 2523/** 2524 * security_net_peersid_resolve - Compare and resolve two network peer SIDs 2525 * @nlbl_sid: NetLabel SID 2526 * @nlbl_type: NetLabel labeling protocol type 2527 * @xfrm_sid: XFRM SID 2528 * 2529 * Description: 2530 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be 2531 * resolved into a single SID it is returned via @peer_sid and the function 2532 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function 2533 * returns a negative value. A table summarizing the behavior is below: 2534 * 2535 * | function return | @sid 2536 * ------------------------------+-----------------+----------------- 2537 * no peer labels | 0 | SECSID_NULL 2538 * single peer label | 0 | <peer_label> 2539 * multiple, consistent labels | 0 | <peer_label> 2540 * multiple, inconsistent labels | -<errno> | SECSID_NULL 2541 * 2542 */ 2543int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type, 2544 u32 xfrm_sid, 2545 u32 *peer_sid) 2546{ 2547 int rc; 2548 struct context *nlbl_ctx; 2549 struct context *xfrm_ctx; 2550 2551 /* handle the common (which also happens to be the set of easy) cases 2552 * right away, these two if statements catch everything involving a 2553 * single or absent peer SID/label */ 2554 if (xfrm_sid == SECSID_NULL) { 2555 *peer_sid = nlbl_sid; 2556 return 0; 2557 } 2558 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label 2559 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label 2560 * is present */ 2561 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { 2562 *peer_sid = xfrm_sid; 2563 return 0; 2564 } 2565 2566 /* we don't need to check ss_initialized here since the only way both 2567 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the 2568 * security server was initialized and ss_initialized was true */ 2569 if (!policydb.mls_enabled) { 2570 *peer_sid = SECSID_NULL; 2571 return 0; 2572 } 2573 2574 read_lock(&policy_rwlock); 2575 2576 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid); 2577 if (!nlbl_ctx) { 2578 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2579 __func__, nlbl_sid); 2580 rc = -EINVAL; 2581 goto out_slowpath; 2582 } 2583 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid); 2584 if (!xfrm_ctx) { 2585 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2586 __func__, xfrm_sid); 2587 rc = -EINVAL; 2588 goto out_slowpath; 2589 } 2590 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); 2591 2592out_slowpath: 2593 read_unlock(&policy_rwlock); 2594 if (rc == 0) 2595 /* at present NetLabel SIDs/labels really only carry MLS 2596 * information so if the MLS portion of the NetLabel SID 2597 * matches the MLS portion of the labeled XFRM SID/label 2598 * then pass along the XFRM SID as it is the most 2599 * expressive */ 2600 *peer_sid = xfrm_sid; 2601 else 2602 *peer_sid = SECSID_NULL; 2603 return rc; 2604} 2605 2606static int get_classes_callback(void *k, void *d, void *args) 2607{ 2608 struct class_datum *datum = d; 2609 char *name = k, **classes = args; 2610 int value = datum->value - 1; 2611 2612 classes[value] = kstrdup(name, GFP_ATOMIC); 2613 if (!classes[value]) 2614 return -ENOMEM; 2615 2616 return 0; 2617} 2618 2619int security_get_classes(char ***classes, int *nclasses) 2620{ 2621 int rc = -ENOMEM; 2622 2623 read_lock(&policy_rwlock); 2624 2625 *nclasses = policydb.p_classes.nprim; 2626 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); 2627 if (!*classes) 2628 goto out; 2629 2630 rc = hashtab_map(policydb.p_classes.table, get_classes_callback, 2631 *classes); 2632 if (rc < 0) { 2633 int i; 2634 for (i = 0; i < *nclasses; i++) 2635 kfree((*classes)[i]); 2636 kfree(*classes); 2637 } 2638 2639out: 2640 read_unlock(&policy_rwlock); 2641 return rc; 2642} 2643 2644static int get_permissions_callback(void *k, void *d, void *args) 2645{ 2646 struct perm_datum *datum = d; 2647 char *name = k, **perms = args; 2648 int value = datum->value - 1; 2649 2650 perms[value] = kstrdup(name, GFP_ATOMIC); 2651 if (!perms[value]) 2652 return -ENOMEM; 2653 2654 return 0; 2655} 2656 2657int security_get_permissions(char *class, char ***perms, int *nperms) 2658{ 2659 int rc = -ENOMEM, i; 2660 struct class_datum *match; 2661 2662 read_lock(&policy_rwlock); 2663 2664 match = hashtab_search(policydb.p_classes.table, class); 2665 if (!match) { 2666 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n", 2667 __func__, class); 2668 rc = -EINVAL; 2669 goto out; 2670 } 2671 2672 *nperms = match->permissions.nprim; 2673 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); 2674 if (!*perms) 2675 goto out; 2676 2677 if (match->comdatum) { 2678 rc = hashtab_map(match->comdatum->permissions.table, 2679 get_permissions_callback, *perms); 2680 if (rc < 0) 2681 goto err; 2682 } 2683 2684 rc = hashtab_map(match->permissions.table, get_permissions_callback, 2685 *perms); 2686 if (rc < 0) 2687 goto err; 2688 2689out: 2690 read_unlock(&policy_rwlock); 2691 return rc; 2692 2693err: 2694 read_unlock(&policy_rwlock); 2695 for (i = 0; i < *nperms; i++) 2696 kfree((*perms)[i]); 2697 kfree(*perms); 2698 return rc; 2699} 2700 2701int security_get_reject_unknown(void) 2702{ 2703 return policydb.reject_unknown; 2704} 2705 2706int security_get_allow_unknown(void) 2707{ 2708 return policydb.allow_unknown; 2709} 2710 2711/** 2712 * security_policycap_supported - Check for a specific policy capability 2713 * @req_cap: capability 2714 * 2715 * Description: 2716 * This function queries the currently loaded policy to see if it supports the 2717 * capability specified by @req_cap. Returns true (1) if the capability is 2718 * supported, false (0) if it isn't supported. 2719 * 2720 */ 2721int security_policycap_supported(unsigned int req_cap) 2722{ 2723 int rc; 2724 2725 read_lock(&policy_rwlock); 2726 rc = ebitmap_get_bit(&policydb.policycaps, req_cap); 2727 read_unlock(&policy_rwlock); 2728 2729 return rc; 2730} 2731 2732struct selinux_audit_rule { 2733 u32 au_seqno; 2734 struct context au_ctxt; 2735}; 2736 2737void selinux_audit_rule_free(void *vrule) 2738{ 2739 struct selinux_audit_rule *rule = vrule; 2740 2741 if (rule) { 2742 context_destroy(&rule->au_ctxt); 2743 kfree(rule); 2744 } 2745} 2746 2747int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 2748{ 2749 struct selinux_audit_rule *tmprule; 2750 struct role_datum *roledatum; 2751 struct type_datum *typedatum; 2752 struct user_datum *userdatum; 2753 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; 2754 int rc = 0; 2755 2756 *rule = NULL; 2757 2758 if (!ss_initialized) 2759 return -EOPNOTSUPP; 2760 2761 switch (field) { 2762 case AUDIT_SUBJ_USER: 2763 case AUDIT_SUBJ_ROLE: 2764 case AUDIT_SUBJ_TYPE: 2765 case AUDIT_OBJ_USER: 2766 case AUDIT_OBJ_ROLE: 2767 case AUDIT_OBJ_TYPE: 2768 /* only 'equals' and 'not equals' fit user, role, and type */ 2769 if (op != Audit_equal && op != Audit_not_equal) 2770 return -EINVAL; 2771 break; 2772 case AUDIT_SUBJ_SEN: 2773 case AUDIT_SUBJ_CLR: 2774 case AUDIT_OBJ_LEV_LOW: 2775 case AUDIT_OBJ_LEV_HIGH: 2776 /* we do not allow a range, indicated by the presense of '-' */ 2777 if (strchr(rulestr, '-')) 2778 return -EINVAL; 2779 break; 2780 default: 2781 /* only the above fields are valid */ 2782 return -EINVAL; 2783 } 2784 2785 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); 2786 if (!tmprule) 2787 return -ENOMEM; 2788 2789 context_init(&tmprule->au_ctxt); 2790 2791 read_lock(&policy_rwlock); 2792 2793 tmprule->au_seqno = latest_granting; 2794 2795 switch (field) { 2796 case AUDIT_SUBJ_USER: 2797 case AUDIT_OBJ_USER: 2798 userdatum = hashtab_search(policydb.p_users.table, rulestr); 2799 if (!userdatum) 2800 rc = -EINVAL; 2801 else 2802 tmprule->au_ctxt.user = userdatum->value; 2803 break; 2804 case AUDIT_SUBJ_ROLE: 2805 case AUDIT_OBJ_ROLE: 2806 roledatum = hashtab_search(policydb.p_roles.table, rulestr); 2807 if (!roledatum) 2808 rc = -EINVAL; 2809 else 2810 tmprule->au_ctxt.role = roledatum->value; 2811 break; 2812 case AUDIT_SUBJ_TYPE: 2813 case AUDIT_OBJ_TYPE: 2814 typedatum = hashtab_search(policydb.p_types.table, rulestr); 2815 if (!typedatum) 2816 rc = -EINVAL; 2817 else 2818 tmprule->au_ctxt.type = typedatum->value; 2819 break; 2820 case AUDIT_SUBJ_SEN: 2821 case AUDIT_SUBJ_CLR: 2822 case AUDIT_OBJ_LEV_LOW: 2823 case AUDIT_OBJ_LEV_HIGH: 2824 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC); 2825 break; 2826 } 2827 2828 read_unlock(&policy_rwlock); 2829 2830 if (rc) { 2831 selinux_audit_rule_free(tmprule); 2832 tmprule = NULL; 2833 } 2834 2835 *rule = tmprule; 2836 2837 return rc; 2838} 2839 2840/* Check to see if the rule contains any selinux fields */ 2841int selinux_audit_rule_known(struct audit_krule *rule) 2842{ 2843 int i; 2844 2845 for (i = 0; i < rule->field_count; i++) { 2846 struct audit_field *f = &rule->fields[i]; 2847 switch (f->type) { 2848 case AUDIT_SUBJ_USER: 2849 case AUDIT_SUBJ_ROLE: 2850 case AUDIT_SUBJ_TYPE: 2851 case AUDIT_SUBJ_SEN: 2852 case AUDIT_SUBJ_CLR: 2853 case AUDIT_OBJ_USER: 2854 case AUDIT_OBJ_ROLE: 2855 case AUDIT_OBJ_TYPE: 2856 case AUDIT_OBJ_LEV_LOW: 2857 case AUDIT_OBJ_LEV_HIGH: 2858 return 1; 2859 } 2860 } 2861 2862 return 0; 2863} 2864 2865int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, 2866 struct audit_context *actx) 2867{ 2868 struct context *ctxt; 2869 struct mls_level *level; 2870 struct selinux_audit_rule *rule = vrule; 2871 int match = 0; 2872 2873 if (!rule) { 2874 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2875 "selinux_audit_rule_match: missing rule\n"); 2876 return -ENOENT; 2877 } 2878 2879 read_lock(&policy_rwlock); 2880 2881 if (rule->au_seqno < latest_granting) { 2882 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2883 "selinux_audit_rule_match: stale rule\n"); 2884 match = -ESTALE; 2885 goto out; 2886 } 2887 2888 ctxt = sidtab_search(&sidtab, sid); 2889 if (!ctxt) { 2890 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2891 "selinux_audit_rule_match: unrecognized SID %d\n", 2892 sid); 2893 match = -ENOENT; 2894 goto out; 2895 } 2896 2897 /* a field/op pair that is not caught here will simply fall through 2898 without a match */ 2899 switch (field) { 2900 case AUDIT_SUBJ_USER: 2901 case AUDIT_OBJ_USER: 2902 switch (op) { 2903 case Audit_equal: 2904 match = (ctxt->user == rule->au_ctxt.user); 2905 break; 2906 case Audit_not_equal: 2907 match = (ctxt->user != rule->au_ctxt.user); 2908 break; 2909 } 2910 break; 2911 case AUDIT_SUBJ_ROLE: 2912 case AUDIT_OBJ_ROLE: 2913 switch (op) { 2914 case Audit_equal: 2915 match = (ctxt->role == rule->au_ctxt.role); 2916 break; 2917 case Audit_not_equal: 2918 match = (ctxt->role != rule->au_ctxt.role); 2919 break; 2920 } 2921 break; 2922 case AUDIT_SUBJ_TYPE: 2923 case AUDIT_OBJ_TYPE: 2924 switch (op) { 2925 case Audit_equal: 2926 match = (ctxt->type == rule->au_ctxt.type); 2927 break; 2928 case Audit_not_equal: 2929 match = (ctxt->type != rule->au_ctxt.type); 2930 break; 2931 } 2932 break; 2933 case AUDIT_SUBJ_SEN: 2934 case AUDIT_SUBJ_CLR: 2935 case AUDIT_OBJ_LEV_LOW: 2936 case AUDIT_OBJ_LEV_HIGH: 2937 level = ((field == AUDIT_SUBJ_SEN || 2938 field == AUDIT_OBJ_LEV_LOW) ? 2939 &ctxt->range.level[0] : &ctxt->range.level[1]); 2940 switch (op) { 2941 case Audit_equal: 2942 match = mls_level_eq(&rule->au_ctxt.range.level[0], 2943 level); 2944 break; 2945 case Audit_not_equal: 2946 match = !mls_level_eq(&rule->au_ctxt.range.level[0], 2947 level); 2948 break; 2949 case Audit_lt: 2950 match = (mls_level_dom(&rule->au_ctxt.range.level[0], 2951 level) && 2952 !mls_level_eq(&rule->au_ctxt.range.level[0], 2953 level)); 2954 break; 2955 case Audit_le: 2956 match = mls_level_dom(&rule->au_ctxt.range.level[0], 2957 level); 2958 break; 2959 case Audit_gt: 2960 match = (mls_level_dom(level, 2961 &rule->au_ctxt.range.level[0]) && 2962 !mls_level_eq(level, 2963 &rule->au_ctxt.range.level[0])); 2964 break; 2965 case Audit_ge: 2966 match = mls_level_dom(level, 2967 &rule->au_ctxt.range.level[0]); 2968 break; 2969 } 2970 } 2971 2972out: 2973 read_unlock(&policy_rwlock); 2974 return match; 2975} 2976 2977static int (*aurule_callback)(void) = audit_update_lsm_rules; 2978 2979static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid, 2980 u16 class, u32 perms, u32 *retained) 2981{ 2982 int err = 0; 2983 2984 if (event == AVC_CALLBACK_RESET && aurule_callback) 2985 err = aurule_callback(); 2986 return err; 2987} 2988 2989static int __init aurule_init(void) 2990{ 2991 int err; 2992 2993 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET, 2994 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0); 2995 if (err) 2996 panic("avc_add_callback() failed, error %d\n", err); 2997 2998 return err; 2999} 3000__initcall(aurule_init); 3001 3002#ifdef CONFIG_NETLABEL 3003/** 3004 * security_netlbl_cache_add - Add an entry to the NetLabel cache 3005 * @secattr: the NetLabel packet security attributes 3006 * @sid: the SELinux SID 3007 * 3008 * Description: 3009 * Attempt to cache the context in @ctx, which was derived from the packet in 3010 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has 3011 * already been initialized. 3012 * 3013 */ 3014static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, 3015 u32 sid) 3016{ 3017 u32 *sid_cache; 3018 3019 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); 3020 if (sid_cache == NULL) 3021 return; 3022 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); 3023 if (secattr->cache == NULL) { 3024 kfree(sid_cache); 3025 return; 3026 } 3027 3028 *sid_cache = sid; 3029 secattr->cache->free = kfree; 3030 secattr->cache->data = sid_cache; 3031 secattr->flags |= NETLBL_SECATTR_CACHE; 3032} 3033 3034/** 3035 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID 3036 * @secattr: the NetLabel packet security attributes 3037 * @sid: the SELinux SID 3038 * 3039 * Description: 3040 * Convert the given NetLabel security attributes in @secattr into a 3041 * SELinux SID. If the @secattr field does not contain a full SELinux 3042 * SID/context then use SECINITSID_NETMSG as the foundation. If possibile the 3043 * 'cache' field of @secattr is set and the CACHE flag is set; this is to 3044 * allow the @secattr to be used by NetLabel to cache the secattr to SID 3045 * conversion for future lookups. Returns zero on success, negative values on 3046 * failure. 3047 * 3048 */ 3049int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, 3050 u32 *sid) 3051{ 3052 int rc = -EIDRM; 3053 struct context *ctx; 3054 struct context ctx_new; 3055 3056 if (!ss_initialized) { 3057 *sid = SECSID_NULL; 3058 return 0; 3059 } 3060 3061 read_lock(&policy_rwlock); 3062 3063 if (secattr->flags & NETLBL_SECATTR_CACHE) { 3064 *sid = *(u32 *)secattr->cache->data; 3065 rc = 0; 3066 } else if (secattr->flags & NETLBL_SECATTR_SECID) { 3067 *sid = secattr->attr.secid; 3068 rc = 0; 3069 } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { 3070 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG); 3071 if (ctx == NULL) 3072 goto netlbl_secattr_to_sid_return; 3073 3074 context_init(&ctx_new); 3075 ctx_new.user = ctx->user; 3076 ctx_new.role = ctx->role; 3077 ctx_new.type = ctx->type; 3078 mls_import_netlbl_lvl(&ctx_new, secattr); 3079 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { 3080 if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat, 3081 secattr->attr.mls.cat) != 0) 3082 goto netlbl_secattr_to_sid_return; 3083 memcpy(&ctx_new.range.level[1].cat, 3084 &ctx_new.range.level[0].cat, 3085 sizeof(ctx_new.range.level[0].cat)); 3086 } 3087 if (mls_context_isvalid(&policydb, &ctx_new) != 1) 3088 goto netlbl_secattr_to_sid_return_cleanup; 3089 3090 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); 3091 if (rc != 0) 3092 goto netlbl_secattr_to_sid_return_cleanup; 3093 3094 security_netlbl_cache_add(secattr, *sid); 3095 3096 ebitmap_destroy(&ctx_new.range.level[0].cat); 3097 } else { 3098 *sid = SECSID_NULL; 3099 rc = 0; 3100 } 3101 3102netlbl_secattr_to_sid_return: 3103 read_unlock(&policy_rwlock); 3104 return rc; 3105netlbl_secattr_to_sid_return_cleanup: 3106 ebitmap_destroy(&ctx_new.range.level[0].cat); 3107 goto netlbl_secattr_to_sid_return; 3108} 3109 3110/** 3111 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr 3112 * @sid: the SELinux SID 3113 * @secattr: the NetLabel packet security attributes 3114 * 3115 * Description: 3116 * Convert the given SELinux SID in @sid into a NetLabel security attribute. 3117 * Returns zero on success, negative values on failure. 3118 * 3119 */ 3120int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr) 3121{ 3122 int rc; 3123 struct context *ctx; 3124 3125 if (!ss_initialized) 3126 return 0; 3127 3128 read_lock(&policy_rwlock); 3129 ctx = sidtab_search(&sidtab, sid); 3130 if (ctx == NULL) { 3131 rc = -ENOENT; 3132 goto netlbl_sid_to_secattr_failure; 3133 } 3134 secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1], 3135 GFP_ATOMIC); 3136 if (secattr->domain == NULL) { 3137 rc = -ENOMEM; 3138 goto netlbl_sid_to_secattr_failure; 3139 } 3140 secattr->attr.secid = sid; 3141 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; 3142 mls_export_netlbl_lvl(ctx, secattr); 3143 rc = mls_export_netlbl_cat(ctx, secattr); 3144 if (rc != 0) 3145 goto netlbl_sid_to_secattr_failure; 3146 read_unlock(&policy_rwlock); 3147 3148 return 0; 3149 3150netlbl_sid_to_secattr_failure: 3151 read_unlock(&policy_rwlock); 3152 return rc; 3153} 3154#endif /* CONFIG_NETLABEL */ 3155 3156/** 3157 * security_read_policy - read the policy. 3158 * @data: binary policy data 3159 * @len: length of data in bytes 3160 * 3161 */ 3162int security_read_policy(void **data, ssize_t *len) 3163{ 3164 int rc; 3165 struct policy_file fp; 3166 3167 if (!ss_initialized) 3168 return -EINVAL; 3169 3170 *len = security_policydb_len(); 3171 3172 *data = vmalloc_user(*len); 3173 if (!*data) 3174 return -ENOMEM; 3175 3176 fp.data = *data; 3177 fp.len = *len; 3178 3179 read_lock(&policy_rwlock); 3180 rc = policydb_write(&policydb, &fp); 3181 read_unlock(&policy_rwlock); 3182 3183 if (rc) 3184 return rc; 3185 3186 *len = (unsigned long)fp.data - (unsigned long)*data; 3187 return 0; 3188 3189} 3190