services.c revision a200005038955057063fc8ea82129ebc785df41c
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 <net/netlabel.h> 54 55#include "flask.h" 56#include "avc.h" 57#include "avc_ss.h" 58#include "security.h" 59#include "context.h" 60#include "policydb.h" 61#include "sidtab.h" 62#include "services.h" 63#include "conditional.h" 64#include "mls.h" 65#include "objsec.h" 66#include "netlabel.h" 67#include "xfrm.h" 68#include "ebitmap.h" 69#include "audit.h" 70 71extern void selnl_notify_policyload(u32 seqno); 72 73int selinux_policycap_netpeer; 74int selinux_policycap_openperm; 75 76static DEFINE_RWLOCK(policy_rwlock); 77 78static struct sidtab sidtab; 79struct policydb policydb; 80int ss_initialized; 81 82/* 83 * The largest sequence number that has been used when 84 * providing an access decision to the access vector cache. 85 * The sequence number only changes when a policy change 86 * occurs. 87 */ 88static u32 latest_granting; 89 90/* Forward declaration. */ 91static int context_struct_to_string(struct context *context, char **scontext, 92 u32 *scontext_len); 93 94static void context_struct_compute_av(struct context *scontext, 95 struct context *tcontext, 96 u16 tclass, 97 struct av_decision *avd); 98 99struct selinux_mapping { 100 u16 value; /* policy value */ 101 unsigned num_perms; 102 u32 perms[sizeof(u32) * 8]; 103}; 104 105static struct selinux_mapping *current_mapping; 106static u16 current_mapping_size; 107 108static int selinux_set_mapping(struct policydb *pol, 109 struct security_class_mapping *map, 110 struct selinux_mapping **out_map_p, 111 u16 *out_map_size) 112{ 113 struct selinux_mapping *out_map = NULL; 114 size_t size = sizeof(struct selinux_mapping); 115 u16 i, j; 116 unsigned k; 117 bool print_unknown_handle = false; 118 119 /* Find number of classes in the input mapping */ 120 if (!map) 121 return -EINVAL; 122 i = 0; 123 while (map[i].name) 124 i++; 125 126 /* Allocate space for the class records, plus one for class zero */ 127 out_map = kcalloc(++i, size, GFP_ATOMIC); 128 if (!out_map) 129 return -ENOMEM; 130 131 /* Store the raw class and permission values */ 132 j = 0; 133 while (map[j].name) { 134 struct security_class_mapping *p_in = map + (j++); 135 struct selinux_mapping *p_out = out_map + j; 136 137 /* An empty class string skips ahead */ 138 if (!strcmp(p_in->name, "")) { 139 p_out->num_perms = 0; 140 continue; 141 } 142 143 p_out->value = string_to_security_class(pol, p_in->name); 144 if (!p_out->value) { 145 printk(KERN_INFO 146 "SELinux: Class %s not defined in policy.\n", 147 p_in->name); 148 if (pol->reject_unknown) 149 goto err; 150 p_out->num_perms = 0; 151 print_unknown_handle = true; 152 continue; 153 } 154 155 k = 0; 156 while (p_in->perms && p_in->perms[k]) { 157 /* An empty permission string skips ahead */ 158 if (!*p_in->perms[k]) { 159 k++; 160 continue; 161 } 162 p_out->perms[k] = string_to_av_perm(pol, p_out->value, 163 p_in->perms[k]); 164 if (!p_out->perms[k]) { 165 printk(KERN_INFO 166 "SELinux: Permission %s in class %s not defined in policy.\n", 167 p_in->perms[k], p_in->name); 168 if (pol->reject_unknown) 169 goto err; 170 print_unknown_handle = true; 171 } 172 173 k++; 174 } 175 p_out->num_perms = k; 176 } 177 178 if (print_unknown_handle) 179 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n", 180 pol->allow_unknown ? "allowed" : "denied"); 181 182 *out_map_p = out_map; 183 *out_map_size = i; 184 return 0; 185err: 186 kfree(out_map); 187 return -EINVAL; 188} 189 190/* 191 * Get real, policy values from mapped values 192 */ 193 194static u16 unmap_class(u16 tclass) 195{ 196 if (tclass < current_mapping_size) 197 return current_mapping[tclass].value; 198 199 return tclass; 200} 201 202static void map_decision(u16 tclass, struct av_decision *avd, 203 int allow_unknown) 204{ 205 if (tclass < current_mapping_size) { 206 unsigned i, n = current_mapping[tclass].num_perms; 207 u32 result; 208 209 for (i = 0, result = 0; i < n; i++) { 210 if (avd->allowed & current_mapping[tclass].perms[i]) 211 result |= 1<<i; 212 if (allow_unknown && !current_mapping[tclass].perms[i]) 213 result |= 1<<i; 214 } 215 avd->allowed = result; 216 217 for (i = 0, result = 0; i < n; i++) 218 if (avd->auditallow & current_mapping[tclass].perms[i]) 219 result |= 1<<i; 220 avd->auditallow = result; 221 222 for (i = 0, result = 0; i < n; i++) { 223 if (avd->auditdeny & current_mapping[tclass].perms[i]) 224 result |= 1<<i; 225 if (!allow_unknown && !current_mapping[tclass].perms[i]) 226 result |= 1<<i; 227 } 228 /* 229 * In case the kernel has a bug and requests a permission 230 * between num_perms and the maximum permission number, we 231 * should audit that denial 232 */ 233 for (; i < (sizeof(u32)*8); i++) 234 result |= 1<<i; 235 avd->auditdeny = result; 236 } 237} 238 239int security_mls_enabled(void) 240{ 241 return policydb.mls_enabled; 242} 243 244/* 245 * Return the boolean value of a constraint expression 246 * when it is applied to the specified source and target 247 * security contexts. 248 * 249 * xcontext is a special beast... It is used by the validatetrans rules 250 * only. For these rules, scontext is the context before the transition, 251 * tcontext is the context after the transition, and xcontext is the context 252 * of the process performing the transition. All other callers of 253 * constraint_expr_eval should pass in NULL for xcontext. 254 */ 255static int constraint_expr_eval(struct context *scontext, 256 struct context *tcontext, 257 struct context *xcontext, 258 struct constraint_expr *cexpr) 259{ 260 u32 val1, val2; 261 struct context *c; 262 struct role_datum *r1, *r2; 263 struct mls_level *l1, *l2; 264 struct constraint_expr *e; 265 int s[CEXPR_MAXDEPTH]; 266 int sp = -1; 267 268 for (e = cexpr; e; e = e->next) { 269 switch (e->expr_type) { 270 case CEXPR_NOT: 271 BUG_ON(sp < 0); 272 s[sp] = !s[sp]; 273 break; 274 case CEXPR_AND: 275 BUG_ON(sp < 1); 276 sp--; 277 s[sp] &= s[sp + 1]; 278 break; 279 case CEXPR_OR: 280 BUG_ON(sp < 1); 281 sp--; 282 s[sp] |= s[sp + 1]; 283 break; 284 case CEXPR_ATTR: 285 if (sp == (CEXPR_MAXDEPTH - 1)) 286 return 0; 287 switch (e->attr) { 288 case CEXPR_USER: 289 val1 = scontext->user; 290 val2 = tcontext->user; 291 break; 292 case CEXPR_TYPE: 293 val1 = scontext->type; 294 val2 = tcontext->type; 295 break; 296 case CEXPR_ROLE: 297 val1 = scontext->role; 298 val2 = tcontext->role; 299 r1 = policydb.role_val_to_struct[val1 - 1]; 300 r2 = policydb.role_val_to_struct[val2 - 1]; 301 switch (e->op) { 302 case CEXPR_DOM: 303 s[++sp] = ebitmap_get_bit(&r1->dominates, 304 val2 - 1); 305 continue; 306 case CEXPR_DOMBY: 307 s[++sp] = ebitmap_get_bit(&r2->dominates, 308 val1 - 1); 309 continue; 310 case CEXPR_INCOMP: 311 s[++sp] = (!ebitmap_get_bit(&r1->dominates, 312 val2 - 1) && 313 !ebitmap_get_bit(&r2->dominates, 314 val1 - 1)); 315 continue; 316 default: 317 break; 318 } 319 break; 320 case CEXPR_L1L2: 321 l1 = &(scontext->range.level[0]); 322 l2 = &(tcontext->range.level[0]); 323 goto mls_ops; 324 case CEXPR_L1H2: 325 l1 = &(scontext->range.level[0]); 326 l2 = &(tcontext->range.level[1]); 327 goto mls_ops; 328 case CEXPR_H1L2: 329 l1 = &(scontext->range.level[1]); 330 l2 = &(tcontext->range.level[0]); 331 goto mls_ops; 332 case CEXPR_H1H2: 333 l1 = &(scontext->range.level[1]); 334 l2 = &(tcontext->range.level[1]); 335 goto mls_ops; 336 case CEXPR_L1H1: 337 l1 = &(scontext->range.level[0]); 338 l2 = &(scontext->range.level[1]); 339 goto mls_ops; 340 case CEXPR_L2H2: 341 l1 = &(tcontext->range.level[0]); 342 l2 = &(tcontext->range.level[1]); 343 goto mls_ops; 344mls_ops: 345 switch (e->op) { 346 case CEXPR_EQ: 347 s[++sp] = mls_level_eq(l1, l2); 348 continue; 349 case CEXPR_NEQ: 350 s[++sp] = !mls_level_eq(l1, l2); 351 continue; 352 case CEXPR_DOM: 353 s[++sp] = mls_level_dom(l1, l2); 354 continue; 355 case CEXPR_DOMBY: 356 s[++sp] = mls_level_dom(l2, l1); 357 continue; 358 case CEXPR_INCOMP: 359 s[++sp] = mls_level_incomp(l2, l1); 360 continue; 361 default: 362 BUG(); 363 return 0; 364 } 365 break; 366 default: 367 BUG(); 368 return 0; 369 } 370 371 switch (e->op) { 372 case CEXPR_EQ: 373 s[++sp] = (val1 == val2); 374 break; 375 case CEXPR_NEQ: 376 s[++sp] = (val1 != val2); 377 break; 378 default: 379 BUG(); 380 return 0; 381 } 382 break; 383 case CEXPR_NAMES: 384 if (sp == (CEXPR_MAXDEPTH-1)) 385 return 0; 386 c = scontext; 387 if (e->attr & CEXPR_TARGET) 388 c = tcontext; 389 else if (e->attr & CEXPR_XTARGET) { 390 c = xcontext; 391 if (!c) { 392 BUG(); 393 return 0; 394 } 395 } 396 if (e->attr & CEXPR_USER) 397 val1 = c->user; 398 else if (e->attr & CEXPR_ROLE) 399 val1 = c->role; 400 else if (e->attr & CEXPR_TYPE) 401 val1 = c->type; 402 else { 403 BUG(); 404 return 0; 405 } 406 407 switch (e->op) { 408 case CEXPR_EQ: 409 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); 410 break; 411 case CEXPR_NEQ: 412 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); 413 break; 414 default: 415 BUG(); 416 return 0; 417 } 418 break; 419 default: 420 BUG(); 421 return 0; 422 } 423 } 424 425 BUG_ON(sp != 0); 426 return s[0]; 427} 428 429/* 430 * security_dump_masked_av - dumps masked permissions during 431 * security_compute_av due to RBAC, MLS/Constraint and Type bounds. 432 */ 433static int dump_masked_av_helper(void *k, void *d, void *args) 434{ 435 struct perm_datum *pdatum = d; 436 char **permission_names = args; 437 438 BUG_ON(pdatum->value < 1 || pdatum->value > 32); 439 440 permission_names[pdatum->value - 1] = (char *)k; 441 442 return 0; 443} 444 445static void security_dump_masked_av(struct context *scontext, 446 struct context *tcontext, 447 u16 tclass, 448 u32 permissions, 449 const char *reason) 450{ 451 struct common_datum *common_dat; 452 struct class_datum *tclass_dat; 453 struct audit_buffer *ab; 454 char *tclass_name; 455 char *scontext_name = NULL; 456 char *tcontext_name = NULL; 457 char *permission_names[32]; 458 int index; 459 u32 length; 460 bool need_comma = false; 461 462 if (!permissions) 463 return; 464 465 tclass_name = policydb.p_class_val_to_name[tclass - 1]; 466 tclass_dat = policydb.class_val_to_struct[tclass - 1]; 467 common_dat = tclass_dat->comdatum; 468 469 /* init permission_names */ 470 if (common_dat && 471 hashtab_map(common_dat->permissions.table, 472 dump_masked_av_helper, permission_names) < 0) 473 goto out; 474 475 if (hashtab_map(tclass_dat->permissions.table, 476 dump_masked_av_helper, permission_names) < 0) 477 goto out; 478 479 /* get scontext/tcontext in text form */ 480 if (context_struct_to_string(scontext, 481 &scontext_name, &length) < 0) 482 goto out; 483 484 if (context_struct_to_string(tcontext, 485 &tcontext_name, &length) < 0) 486 goto out; 487 488 /* audit a message */ 489 ab = audit_log_start(current->audit_context, 490 GFP_ATOMIC, AUDIT_SELINUX_ERR); 491 if (!ab) 492 goto out; 493 494 audit_log_format(ab, "op=security_compute_av reason=%s " 495 "scontext=%s tcontext=%s tclass=%s perms=", 496 reason, scontext_name, tcontext_name, tclass_name); 497 498 for (index = 0; index < 32; index++) { 499 u32 mask = (1 << index); 500 501 if ((mask & permissions) == 0) 502 continue; 503 504 audit_log_format(ab, "%s%s", 505 need_comma ? "," : "", 506 permission_names[index] 507 ? permission_names[index] : "????"); 508 need_comma = true; 509 } 510 audit_log_end(ab); 511out: 512 /* release scontext/tcontext */ 513 kfree(tcontext_name); 514 kfree(scontext_name); 515 516 return; 517} 518 519/* 520 * security_boundary_permission - drops violated permissions 521 * on boundary constraint. 522 */ 523static void type_attribute_bounds_av(struct context *scontext, 524 struct context *tcontext, 525 u16 tclass, 526 struct av_decision *avd) 527{ 528 struct context lo_scontext; 529 struct context lo_tcontext; 530 struct av_decision lo_avd; 531 struct type_datum *source 532 = policydb.type_val_to_struct[scontext->type - 1]; 533 struct type_datum *target 534 = policydb.type_val_to_struct[tcontext->type - 1]; 535 u32 masked = 0; 536 537 if (source->bounds) { 538 memset(&lo_avd, 0, sizeof(lo_avd)); 539 540 memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); 541 lo_scontext.type = source->bounds; 542 543 context_struct_compute_av(&lo_scontext, 544 tcontext, 545 tclass, 546 &lo_avd); 547 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 548 return; /* no masked permission */ 549 masked = ~lo_avd.allowed & avd->allowed; 550 } 551 552 if (target->bounds) { 553 memset(&lo_avd, 0, sizeof(lo_avd)); 554 555 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); 556 lo_tcontext.type = target->bounds; 557 558 context_struct_compute_av(scontext, 559 &lo_tcontext, 560 tclass, 561 &lo_avd); 562 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 563 return; /* no masked permission */ 564 masked = ~lo_avd.allowed & avd->allowed; 565 } 566 567 if (source->bounds && target->bounds) { 568 memset(&lo_avd, 0, sizeof(lo_avd)); 569 /* 570 * lo_scontext and lo_tcontext are already 571 * set up. 572 */ 573 574 context_struct_compute_av(&lo_scontext, 575 &lo_tcontext, 576 tclass, 577 &lo_avd); 578 if ((lo_avd.allowed & avd->allowed) == avd->allowed) 579 return; /* no masked permission */ 580 masked = ~lo_avd.allowed & avd->allowed; 581 } 582 583 if (masked) { 584 /* mask violated permissions */ 585 avd->allowed &= ~masked; 586 587 /* audit masked permissions */ 588 security_dump_masked_av(scontext, tcontext, 589 tclass, masked, "bounds"); 590 } 591} 592 593/* 594 * Compute access vectors based on a context structure pair for 595 * the permissions in a particular class. 596 */ 597static void context_struct_compute_av(struct context *scontext, 598 struct context *tcontext, 599 u16 tclass, 600 struct av_decision *avd) 601{ 602 struct constraint_node *constraint; 603 struct role_allow *ra; 604 struct avtab_key avkey; 605 struct avtab_node *node; 606 struct class_datum *tclass_datum; 607 struct ebitmap *sattr, *tattr; 608 struct ebitmap_node *snode, *tnode; 609 unsigned int i, j; 610 611 avd->allowed = 0; 612 avd->auditallow = 0; 613 avd->auditdeny = 0xffffffff; 614 615 if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { 616 if (printk_ratelimit()) 617 printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); 618 return; 619 } 620 621 tclass_datum = policydb.class_val_to_struct[tclass - 1]; 622 623 /* 624 * If a specific type enforcement rule was defined for 625 * this permission check, then use it. 626 */ 627 avkey.target_class = tclass; 628 avkey.specified = AVTAB_AV; 629 sattr = &policydb.type_attr_map[scontext->type - 1]; 630 tattr = &policydb.type_attr_map[tcontext->type - 1]; 631 ebitmap_for_each_positive_bit(sattr, snode, i) { 632 ebitmap_for_each_positive_bit(tattr, tnode, j) { 633 avkey.source_type = i + 1; 634 avkey.target_type = j + 1; 635 for (node = avtab_search_node(&policydb.te_avtab, &avkey); 636 node; 637 node = avtab_search_node_next(node, avkey.specified)) { 638 if (node->key.specified == AVTAB_ALLOWED) 639 avd->allowed |= node->datum.data; 640 else if (node->key.specified == AVTAB_AUDITALLOW) 641 avd->auditallow |= node->datum.data; 642 else if (node->key.specified == AVTAB_AUDITDENY) 643 avd->auditdeny &= node->datum.data; 644 } 645 646 /* Check conditional av table for additional permissions */ 647 cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); 648 649 } 650 } 651 652 /* 653 * Remove any permissions prohibited by a constraint (this includes 654 * the MLS policy). 655 */ 656 constraint = tclass_datum->constraints; 657 while (constraint) { 658 if ((constraint->permissions & (avd->allowed)) && 659 !constraint_expr_eval(scontext, tcontext, NULL, 660 constraint->expr)) { 661 avd->allowed &= ~(constraint->permissions); 662 } 663 constraint = constraint->next; 664 } 665 666 /* 667 * If checking process transition permission and the 668 * role is changing, then check the (current_role, new_role) 669 * pair. 670 */ 671 if (tclass == policydb.process_class && 672 (avd->allowed & policydb.process_trans_perms) && 673 scontext->role != tcontext->role) { 674 for (ra = policydb.role_allow; ra; ra = ra->next) { 675 if (scontext->role == ra->role && 676 tcontext->role == ra->new_role) 677 break; 678 } 679 if (!ra) 680 avd->allowed &= ~policydb.process_trans_perms; 681 } 682 683 /* 684 * If the given source and target types have boundary 685 * constraint, lazy checks have to mask any violated 686 * permission and notice it to userspace via audit. 687 */ 688 type_attribute_bounds_av(scontext, tcontext, 689 tclass, avd); 690} 691 692static int security_validtrans_handle_fail(struct context *ocontext, 693 struct context *ncontext, 694 struct context *tcontext, 695 u16 tclass) 696{ 697 char *o = NULL, *n = NULL, *t = NULL; 698 u32 olen, nlen, tlen; 699 700 if (context_struct_to_string(ocontext, &o, &olen) < 0) 701 goto out; 702 if (context_struct_to_string(ncontext, &n, &nlen) < 0) 703 goto out; 704 if (context_struct_to_string(tcontext, &t, &tlen) < 0) 705 goto out; 706 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 707 "security_validate_transition: denied for" 708 " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", 709 o, n, t, policydb.p_class_val_to_name[tclass-1]); 710out: 711 kfree(o); 712 kfree(n); 713 kfree(t); 714 715 if (!selinux_enforcing) 716 return 0; 717 return -EPERM; 718} 719 720int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, 721 u16 orig_tclass) 722{ 723 struct context *ocontext; 724 struct context *ncontext; 725 struct context *tcontext; 726 struct class_datum *tclass_datum; 727 struct constraint_node *constraint; 728 u16 tclass; 729 int rc = 0; 730 731 if (!ss_initialized) 732 return 0; 733 734 read_lock(&policy_rwlock); 735 736 tclass = unmap_class(orig_tclass); 737 738 if (!tclass || tclass > policydb.p_classes.nprim) { 739 printk(KERN_ERR "SELinux: %s: unrecognized class %d\n", 740 __func__, tclass); 741 rc = -EINVAL; 742 goto out; 743 } 744 tclass_datum = policydb.class_val_to_struct[tclass - 1]; 745 746 ocontext = sidtab_search(&sidtab, oldsid); 747 if (!ocontext) { 748 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 749 __func__, oldsid); 750 rc = -EINVAL; 751 goto out; 752 } 753 754 ncontext = sidtab_search(&sidtab, newsid); 755 if (!ncontext) { 756 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 757 __func__, newsid); 758 rc = -EINVAL; 759 goto out; 760 } 761 762 tcontext = sidtab_search(&sidtab, tasksid); 763 if (!tcontext) { 764 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 765 __func__, tasksid); 766 rc = -EINVAL; 767 goto out; 768 } 769 770 constraint = tclass_datum->validatetrans; 771 while (constraint) { 772 if (!constraint_expr_eval(ocontext, ncontext, tcontext, 773 constraint->expr)) { 774 rc = security_validtrans_handle_fail(ocontext, ncontext, 775 tcontext, tclass); 776 goto out; 777 } 778 constraint = constraint->next; 779 } 780 781out: 782 read_unlock(&policy_rwlock); 783 return rc; 784} 785 786/* 787 * security_bounded_transition - check whether the given 788 * transition is directed to bounded, or not. 789 * It returns 0, if @newsid is bounded by @oldsid. 790 * Otherwise, it returns error code. 791 * 792 * @oldsid : current security identifier 793 * @newsid : destinated security identifier 794 */ 795int security_bounded_transition(u32 old_sid, u32 new_sid) 796{ 797 struct context *old_context, *new_context; 798 struct type_datum *type; 799 int index; 800 int rc = -EINVAL; 801 802 read_lock(&policy_rwlock); 803 804 old_context = sidtab_search(&sidtab, old_sid); 805 if (!old_context) { 806 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 807 __func__, old_sid); 808 goto out; 809 } 810 811 new_context = sidtab_search(&sidtab, new_sid); 812 if (!new_context) { 813 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", 814 __func__, new_sid); 815 goto out; 816 } 817 818 /* type/domain unchanged */ 819 if (old_context->type == new_context->type) { 820 rc = 0; 821 goto out; 822 } 823 824 index = new_context->type; 825 while (true) { 826 type = policydb.type_val_to_struct[index - 1]; 827 BUG_ON(!type); 828 829 /* not bounded anymore */ 830 if (!type->bounds) { 831 rc = -EPERM; 832 break; 833 } 834 835 /* @newsid is bounded by @oldsid */ 836 if (type->bounds == old_context->type) { 837 rc = 0; 838 break; 839 } 840 index = type->bounds; 841 } 842 843 if (rc) { 844 char *old_name = NULL; 845 char *new_name = NULL; 846 u32 length; 847 848 if (!context_struct_to_string(old_context, 849 &old_name, &length) && 850 !context_struct_to_string(new_context, 851 &new_name, &length)) { 852 audit_log(current->audit_context, 853 GFP_ATOMIC, AUDIT_SELINUX_ERR, 854 "op=security_bounded_transition " 855 "result=denied " 856 "oldcontext=%s newcontext=%s", 857 old_name, new_name); 858 } 859 kfree(new_name); 860 kfree(old_name); 861 } 862out: 863 read_unlock(&policy_rwlock); 864 865 return rc; 866} 867 868static void avd_init(struct av_decision *avd) 869{ 870 avd->allowed = 0; 871 avd->auditallow = 0; 872 avd->auditdeny = 0xffffffff; 873 avd->seqno = latest_granting; 874 avd->flags = 0; 875} 876 877 878/** 879 * security_compute_av - Compute access vector decisions. 880 * @ssid: source security identifier 881 * @tsid: target security identifier 882 * @tclass: target security class 883 * @avd: access vector decisions 884 * 885 * Compute a set of access vector decisions based on the 886 * SID pair (@ssid, @tsid) for the permissions in @tclass. 887 */ 888void security_compute_av(u32 ssid, 889 u32 tsid, 890 u16 orig_tclass, 891 struct av_decision *avd) 892{ 893 u16 tclass; 894 struct context *scontext = NULL, *tcontext = NULL; 895 896 read_lock(&policy_rwlock); 897 avd_init(avd); 898 if (!ss_initialized) 899 goto allow; 900 901 scontext = sidtab_search(&sidtab, ssid); 902 if (!scontext) { 903 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 904 __func__, ssid); 905 goto out; 906 } 907 908 /* permissive domain? */ 909 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) 910 avd->flags |= AVD_FLAGS_PERMISSIVE; 911 912 tcontext = sidtab_search(&sidtab, tsid); 913 if (!tcontext) { 914 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 915 __func__, tsid); 916 goto out; 917 } 918 919 tclass = unmap_class(orig_tclass); 920 if (unlikely(orig_tclass && !tclass)) { 921 if (policydb.allow_unknown) 922 goto allow; 923 goto out; 924 } 925 context_struct_compute_av(scontext, tcontext, tclass, avd); 926 map_decision(orig_tclass, avd, policydb.allow_unknown); 927out: 928 read_unlock(&policy_rwlock); 929 return; 930allow: 931 avd->allowed = 0xffffffff; 932 goto out; 933} 934 935void security_compute_av_user(u32 ssid, 936 u32 tsid, 937 u16 tclass, 938 struct av_decision *avd) 939{ 940 struct context *scontext = NULL, *tcontext = NULL; 941 942 read_lock(&policy_rwlock); 943 avd_init(avd); 944 if (!ss_initialized) 945 goto allow; 946 947 scontext = sidtab_search(&sidtab, ssid); 948 if (!scontext) { 949 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 950 __func__, ssid); 951 goto out; 952 } 953 954 /* permissive domain? */ 955 if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) 956 avd->flags |= AVD_FLAGS_PERMISSIVE; 957 958 tcontext = sidtab_search(&sidtab, tsid); 959 if (!tcontext) { 960 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 961 __func__, tsid); 962 goto out; 963 } 964 965 if (unlikely(!tclass)) { 966 if (policydb.allow_unknown) 967 goto allow; 968 goto out; 969 } 970 971 context_struct_compute_av(scontext, tcontext, tclass, avd); 972 out: 973 read_unlock(&policy_rwlock); 974 return; 975allow: 976 avd->allowed = 0xffffffff; 977 goto out; 978} 979 980/* 981 * Write the security context string representation of 982 * the context structure `context' into a dynamically 983 * allocated string of the correct size. Set `*scontext' 984 * to point to this string and set `*scontext_len' to 985 * the length of the string. 986 */ 987static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len) 988{ 989 char *scontextp; 990 991 *scontext = NULL; 992 *scontext_len = 0; 993 994 if (context->len) { 995 *scontext_len = context->len; 996 *scontext = kstrdup(context->str, GFP_ATOMIC); 997 if (!(*scontext)) 998 return -ENOMEM; 999 return 0; 1000 } 1001 1002 /* Compute the size of the context. */ 1003 *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1; 1004 *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1; 1005 *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1; 1006 *scontext_len += mls_compute_context_len(context); 1007 1008 /* Allocate space for the context; caller must free this space. */ 1009 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1010 if (!scontextp) 1011 return -ENOMEM; 1012 *scontext = scontextp; 1013 1014 /* 1015 * Copy the user name, role name and type name into the context. 1016 */ 1017 sprintf(scontextp, "%s:%s:%s", 1018 policydb.p_user_val_to_name[context->user - 1], 1019 policydb.p_role_val_to_name[context->role - 1], 1020 policydb.p_type_val_to_name[context->type - 1]); 1021 scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1022 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) + 1023 1 + strlen(policydb.p_type_val_to_name[context->type - 1]); 1024 1025 mls_sid_to_context(context, &scontextp); 1026 1027 *scontextp = 0; 1028 1029 return 0; 1030} 1031 1032#include "initial_sid_to_string.h" 1033 1034const char *security_get_initial_sid_context(u32 sid) 1035{ 1036 if (unlikely(sid > SECINITSID_NUM)) 1037 return NULL; 1038 return initial_sid_to_string[sid]; 1039} 1040 1041static int security_sid_to_context_core(u32 sid, char **scontext, 1042 u32 *scontext_len, int force) 1043{ 1044 struct context *context; 1045 int rc = 0; 1046 1047 *scontext = NULL; 1048 *scontext_len = 0; 1049 1050 if (!ss_initialized) { 1051 if (sid <= SECINITSID_NUM) { 1052 char *scontextp; 1053 1054 *scontext_len = strlen(initial_sid_to_string[sid]) + 1; 1055 scontextp = kmalloc(*scontext_len, GFP_ATOMIC); 1056 if (!scontextp) { 1057 rc = -ENOMEM; 1058 goto out; 1059 } 1060 strcpy(scontextp, initial_sid_to_string[sid]); 1061 *scontext = scontextp; 1062 goto out; 1063 } 1064 printk(KERN_ERR "SELinux: %s: called before initial " 1065 "load_policy on unknown SID %d\n", __func__, sid); 1066 rc = -EINVAL; 1067 goto out; 1068 } 1069 read_lock(&policy_rwlock); 1070 if (force) 1071 context = sidtab_search_force(&sidtab, sid); 1072 else 1073 context = sidtab_search(&sidtab, sid); 1074 if (!context) { 1075 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1076 __func__, sid); 1077 rc = -EINVAL; 1078 goto out_unlock; 1079 } 1080 rc = context_struct_to_string(context, scontext, scontext_len); 1081out_unlock: 1082 read_unlock(&policy_rwlock); 1083out: 1084 return rc; 1085 1086} 1087 1088/** 1089 * security_sid_to_context - Obtain a context for a given SID. 1090 * @sid: security identifier, SID 1091 * @scontext: security context 1092 * @scontext_len: length in bytes 1093 * 1094 * Write the string representation of the context associated with @sid 1095 * into a dynamically allocated string of the correct size. Set @scontext 1096 * to point to this string and set @scontext_len to the length of the string. 1097 */ 1098int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) 1099{ 1100 return security_sid_to_context_core(sid, scontext, scontext_len, 0); 1101} 1102 1103int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len) 1104{ 1105 return security_sid_to_context_core(sid, scontext, scontext_len, 1); 1106} 1107 1108/* 1109 * Caveat: Mutates scontext. 1110 */ 1111static int string_to_context_struct(struct policydb *pol, 1112 struct sidtab *sidtabp, 1113 char *scontext, 1114 u32 scontext_len, 1115 struct context *ctx, 1116 u32 def_sid) 1117{ 1118 struct role_datum *role; 1119 struct type_datum *typdatum; 1120 struct user_datum *usrdatum; 1121 char *scontextp, *p, oldc; 1122 int rc = 0; 1123 1124 context_init(ctx); 1125 1126 /* Parse the security context. */ 1127 1128 rc = -EINVAL; 1129 scontextp = (char *) scontext; 1130 1131 /* Extract the user. */ 1132 p = scontextp; 1133 while (*p && *p != ':') 1134 p++; 1135 1136 if (*p == 0) 1137 goto out; 1138 1139 *p++ = 0; 1140 1141 usrdatum = hashtab_search(pol->p_users.table, scontextp); 1142 if (!usrdatum) 1143 goto out; 1144 1145 ctx->user = usrdatum->value; 1146 1147 /* Extract role. */ 1148 scontextp = p; 1149 while (*p && *p != ':') 1150 p++; 1151 1152 if (*p == 0) 1153 goto out; 1154 1155 *p++ = 0; 1156 1157 role = hashtab_search(pol->p_roles.table, scontextp); 1158 if (!role) 1159 goto out; 1160 ctx->role = role->value; 1161 1162 /* Extract type. */ 1163 scontextp = p; 1164 while (*p && *p != ':') 1165 p++; 1166 oldc = *p; 1167 *p++ = 0; 1168 1169 typdatum = hashtab_search(pol->p_types.table, scontextp); 1170 if (!typdatum || typdatum->attribute) 1171 goto out; 1172 1173 ctx->type = typdatum->value; 1174 1175 rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid); 1176 if (rc) 1177 goto out; 1178 1179 if ((p - scontext) < scontext_len) { 1180 rc = -EINVAL; 1181 goto out; 1182 } 1183 1184 /* Check the validity of the new context. */ 1185 if (!policydb_context_isvalid(pol, ctx)) { 1186 rc = -EINVAL; 1187 goto out; 1188 } 1189 rc = 0; 1190out: 1191 if (rc) 1192 context_destroy(ctx); 1193 return rc; 1194} 1195 1196static int security_context_to_sid_core(const char *scontext, u32 scontext_len, 1197 u32 *sid, u32 def_sid, gfp_t gfp_flags, 1198 int force) 1199{ 1200 char *scontext2, *str = NULL; 1201 struct context context; 1202 int rc = 0; 1203 1204 if (!ss_initialized) { 1205 int i; 1206 1207 for (i = 1; i < SECINITSID_NUM; i++) { 1208 if (!strcmp(initial_sid_to_string[i], scontext)) { 1209 *sid = i; 1210 return 0; 1211 } 1212 } 1213 *sid = SECINITSID_KERNEL; 1214 return 0; 1215 } 1216 *sid = SECSID_NULL; 1217 1218 /* Copy the string so that we can modify the copy as we parse it. */ 1219 scontext2 = kmalloc(scontext_len + 1, gfp_flags); 1220 if (!scontext2) 1221 return -ENOMEM; 1222 memcpy(scontext2, scontext, scontext_len); 1223 scontext2[scontext_len] = 0; 1224 1225 if (force) { 1226 /* Save another copy for storing in uninterpreted form */ 1227 str = kstrdup(scontext2, gfp_flags); 1228 if (!str) { 1229 kfree(scontext2); 1230 return -ENOMEM; 1231 } 1232 } 1233 1234 read_lock(&policy_rwlock); 1235 rc = string_to_context_struct(&policydb, &sidtab, 1236 scontext2, scontext_len, 1237 &context, def_sid); 1238 if (rc == -EINVAL && force) { 1239 context.str = str; 1240 context.len = scontext_len; 1241 str = NULL; 1242 } else if (rc) 1243 goto out; 1244 rc = sidtab_context_to_sid(&sidtab, &context, sid); 1245 context_destroy(&context); 1246out: 1247 read_unlock(&policy_rwlock); 1248 kfree(scontext2); 1249 kfree(str); 1250 return rc; 1251} 1252 1253/** 1254 * security_context_to_sid - Obtain a SID for a given security context. 1255 * @scontext: security context 1256 * @scontext_len: length in bytes 1257 * @sid: security identifier, SID 1258 * 1259 * Obtains a SID associated with the security context that 1260 * has the string representation specified by @scontext. 1261 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1262 * memory is available, or 0 on success. 1263 */ 1264int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid) 1265{ 1266 return security_context_to_sid_core(scontext, scontext_len, 1267 sid, SECSID_NULL, GFP_KERNEL, 0); 1268} 1269 1270/** 1271 * security_context_to_sid_default - Obtain a SID for a given security context, 1272 * falling back to specified default if needed. 1273 * 1274 * @scontext: security context 1275 * @scontext_len: length in bytes 1276 * @sid: security identifier, SID 1277 * @def_sid: default SID to assign on error 1278 * 1279 * Obtains a SID associated with the security context that 1280 * has the string representation specified by @scontext. 1281 * The default SID is passed to the MLS layer to be used to allow 1282 * kernel labeling of the MLS field if the MLS field is not present 1283 * (for upgrading to MLS without full relabel). 1284 * Implicitly forces adding of the context even if it cannot be mapped yet. 1285 * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient 1286 * memory is available, or 0 on success. 1287 */ 1288int security_context_to_sid_default(const char *scontext, u32 scontext_len, 1289 u32 *sid, u32 def_sid, gfp_t gfp_flags) 1290{ 1291 return security_context_to_sid_core(scontext, scontext_len, 1292 sid, def_sid, gfp_flags, 1); 1293} 1294 1295int security_context_to_sid_force(const char *scontext, u32 scontext_len, 1296 u32 *sid) 1297{ 1298 return security_context_to_sid_core(scontext, scontext_len, 1299 sid, SECSID_NULL, GFP_KERNEL, 1); 1300} 1301 1302static int compute_sid_handle_invalid_context( 1303 struct context *scontext, 1304 struct context *tcontext, 1305 u16 tclass, 1306 struct context *newcontext) 1307{ 1308 char *s = NULL, *t = NULL, *n = NULL; 1309 u32 slen, tlen, nlen; 1310 1311 if (context_struct_to_string(scontext, &s, &slen) < 0) 1312 goto out; 1313 if (context_struct_to_string(tcontext, &t, &tlen) < 0) 1314 goto out; 1315 if (context_struct_to_string(newcontext, &n, &nlen) < 0) 1316 goto out; 1317 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 1318 "security_compute_sid: invalid context %s" 1319 " for scontext=%s" 1320 " tcontext=%s" 1321 " tclass=%s", 1322 n, s, t, policydb.p_class_val_to_name[tclass-1]); 1323out: 1324 kfree(s); 1325 kfree(t); 1326 kfree(n); 1327 if (!selinux_enforcing) 1328 return 0; 1329 return -EACCES; 1330} 1331 1332static int security_compute_sid(u32 ssid, 1333 u32 tsid, 1334 u16 orig_tclass, 1335 u32 specified, 1336 u32 *out_sid, 1337 bool kern) 1338{ 1339 struct context *scontext = NULL, *tcontext = NULL, newcontext; 1340 struct role_trans *roletr = NULL; 1341 struct avtab_key avkey; 1342 struct avtab_datum *avdatum; 1343 struct avtab_node *node; 1344 u16 tclass; 1345 int rc = 0; 1346 1347 if (!ss_initialized) { 1348 switch (orig_tclass) { 1349 case SECCLASS_PROCESS: /* kernel value */ 1350 *out_sid = ssid; 1351 break; 1352 default: 1353 *out_sid = tsid; 1354 break; 1355 } 1356 goto out; 1357 } 1358 1359 context_init(&newcontext); 1360 1361 read_lock(&policy_rwlock); 1362 1363 if (kern) 1364 tclass = unmap_class(orig_tclass); 1365 else 1366 tclass = orig_tclass; 1367 1368 scontext = sidtab_search(&sidtab, ssid); 1369 if (!scontext) { 1370 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1371 __func__, ssid); 1372 rc = -EINVAL; 1373 goto out_unlock; 1374 } 1375 tcontext = sidtab_search(&sidtab, tsid); 1376 if (!tcontext) { 1377 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 1378 __func__, tsid); 1379 rc = -EINVAL; 1380 goto out_unlock; 1381 } 1382 1383 /* Set the user identity. */ 1384 switch (specified) { 1385 case AVTAB_TRANSITION: 1386 case AVTAB_CHANGE: 1387 /* Use the process user identity. */ 1388 newcontext.user = scontext->user; 1389 break; 1390 case AVTAB_MEMBER: 1391 /* Use the related object owner. */ 1392 newcontext.user = tcontext->user; 1393 break; 1394 } 1395 1396 /* Set the role and type to default values. */ 1397 if (tclass == policydb.process_class) { 1398 /* Use the current role and type of process. */ 1399 newcontext.role = scontext->role; 1400 newcontext.type = scontext->type; 1401 } else { 1402 /* Use the well-defined object role. */ 1403 newcontext.role = OBJECT_R_VAL; 1404 /* Use the type of the related object. */ 1405 newcontext.type = tcontext->type; 1406 } 1407 1408 /* Look for a type transition/member/change rule. */ 1409 avkey.source_type = scontext->type; 1410 avkey.target_type = tcontext->type; 1411 avkey.target_class = tclass; 1412 avkey.specified = specified; 1413 avdatum = avtab_search(&policydb.te_avtab, &avkey); 1414 1415 /* If no permanent rule, also check for enabled conditional rules */ 1416 if (!avdatum) { 1417 node = avtab_search_node(&policydb.te_cond_avtab, &avkey); 1418 for (; node; node = avtab_search_node_next(node, specified)) { 1419 if (node->key.specified & AVTAB_ENABLED) { 1420 avdatum = &node->datum; 1421 break; 1422 } 1423 } 1424 } 1425 1426 if (avdatum) { 1427 /* Use the type from the type transition/member/change rule. */ 1428 newcontext.type = avdatum->data; 1429 } 1430 1431 /* Check for class-specific changes. */ 1432 if (tclass == policydb.process_class) { 1433 if (specified & AVTAB_TRANSITION) { 1434 /* Look for a role transition rule. */ 1435 for (roletr = policydb.role_tr; roletr; 1436 roletr = roletr->next) { 1437 if (roletr->role == scontext->role && 1438 roletr->type == tcontext->type) { 1439 /* Use the role transition rule. */ 1440 newcontext.role = roletr->new_role; 1441 break; 1442 } 1443 } 1444 } 1445 } 1446 1447 /* Set the MLS attributes. 1448 This is done last because it may allocate memory. */ 1449 rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext); 1450 if (rc) 1451 goto out_unlock; 1452 1453 /* Check the validity of the context. */ 1454 if (!policydb_context_isvalid(&policydb, &newcontext)) { 1455 rc = compute_sid_handle_invalid_context(scontext, 1456 tcontext, 1457 tclass, 1458 &newcontext); 1459 if (rc) 1460 goto out_unlock; 1461 } 1462 /* Obtain the sid for the context. */ 1463 rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid); 1464out_unlock: 1465 read_unlock(&policy_rwlock); 1466 context_destroy(&newcontext); 1467out: 1468 return rc; 1469} 1470 1471/** 1472 * security_transition_sid - Compute the SID for a new subject/object. 1473 * @ssid: source security identifier 1474 * @tsid: target security identifier 1475 * @tclass: target security class 1476 * @out_sid: security identifier for new subject/object 1477 * 1478 * Compute a SID to use for labeling a new subject or object in the 1479 * class @tclass based on a SID pair (@ssid, @tsid). 1480 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1481 * if insufficient memory is available, or %0 if the new SID was 1482 * computed successfully. 1483 */ 1484int security_transition_sid(u32 ssid, 1485 u32 tsid, 1486 u16 tclass, 1487 u32 *out_sid) 1488{ 1489 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, 1490 out_sid, true); 1491} 1492 1493int security_transition_sid_user(u32 ssid, 1494 u32 tsid, 1495 u16 tclass, 1496 u32 *out_sid) 1497{ 1498 return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, 1499 out_sid, false); 1500} 1501 1502/** 1503 * security_member_sid - Compute the SID for member selection. 1504 * @ssid: source security identifier 1505 * @tsid: target security identifier 1506 * @tclass: target security class 1507 * @out_sid: security identifier for selected member 1508 * 1509 * Compute a SID to use when selecting a member of a polyinstantiated 1510 * object of class @tclass based on a SID pair (@ssid, @tsid). 1511 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1512 * if insufficient memory is available, or %0 if the SID was 1513 * computed successfully. 1514 */ 1515int security_member_sid(u32 ssid, 1516 u32 tsid, 1517 u16 tclass, 1518 u32 *out_sid) 1519{ 1520 return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid, 1521 false); 1522} 1523 1524/** 1525 * security_change_sid - Compute the SID for object relabeling. 1526 * @ssid: source security identifier 1527 * @tsid: target security identifier 1528 * @tclass: target security class 1529 * @out_sid: security identifier for selected member 1530 * 1531 * Compute a SID to use for relabeling an object of class @tclass 1532 * based on a SID pair (@ssid, @tsid). 1533 * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM 1534 * if insufficient memory is available, or %0 if the SID was 1535 * computed successfully. 1536 */ 1537int security_change_sid(u32 ssid, 1538 u32 tsid, 1539 u16 tclass, 1540 u32 *out_sid) 1541{ 1542 return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid, 1543 false); 1544} 1545 1546/* Clone the SID into the new SID table. */ 1547static int clone_sid(u32 sid, 1548 struct context *context, 1549 void *arg) 1550{ 1551 struct sidtab *s = arg; 1552 1553 if (sid > SECINITSID_NUM) 1554 return sidtab_insert(s, sid, context); 1555 else 1556 return 0; 1557} 1558 1559static inline int convert_context_handle_invalid_context(struct context *context) 1560{ 1561 int rc = 0; 1562 1563 if (selinux_enforcing) { 1564 rc = -EINVAL; 1565 } else { 1566 char *s; 1567 u32 len; 1568 1569 if (!context_struct_to_string(context, &s, &len)) { 1570 printk(KERN_WARNING 1571 "SELinux: Context %s would be invalid if enforcing\n", 1572 s); 1573 kfree(s); 1574 } 1575 } 1576 return rc; 1577} 1578 1579struct convert_context_args { 1580 struct policydb *oldp; 1581 struct policydb *newp; 1582}; 1583 1584/* 1585 * Convert the values in the security context 1586 * structure `c' from the values specified 1587 * in the policy `p->oldp' to the values specified 1588 * in the policy `p->newp'. Verify that the 1589 * context is valid under the new policy. 1590 */ 1591static int convert_context(u32 key, 1592 struct context *c, 1593 void *p) 1594{ 1595 struct convert_context_args *args; 1596 struct context oldc; 1597 struct ocontext *oc; 1598 struct mls_range *range; 1599 struct role_datum *role; 1600 struct type_datum *typdatum; 1601 struct user_datum *usrdatum; 1602 char *s; 1603 u32 len; 1604 int rc = 0; 1605 1606 if (key <= SECINITSID_NUM) 1607 goto out; 1608 1609 args = p; 1610 1611 if (c->str) { 1612 struct context ctx; 1613 s = kstrdup(c->str, GFP_KERNEL); 1614 if (!s) { 1615 rc = -ENOMEM; 1616 goto out; 1617 } 1618 rc = string_to_context_struct(args->newp, NULL, s, 1619 c->len, &ctx, SECSID_NULL); 1620 kfree(s); 1621 if (!rc) { 1622 printk(KERN_INFO 1623 "SELinux: Context %s became valid (mapped).\n", 1624 c->str); 1625 /* Replace string with mapped representation. */ 1626 kfree(c->str); 1627 memcpy(c, &ctx, sizeof(*c)); 1628 goto out; 1629 } else if (rc == -EINVAL) { 1630 /* Retain string representation for later mapping. */ 1631 rc = 0; 1632 goto out; 1633 } else { 1634 /* Other error condition, e.g. ENOMEM. */ 1635 printk(KERN_ERR 1636 "SELinux: Unable to map context %s, rc = %d.\n", 1637 c->str, -rc); 1638 goto out; 1639 } 1640 } 1641 1642 rc = context_cpy(&oldc, c); 1643 if (rc) 1644 goto out; 1645 1646 rc = -EINVAL; 1647 1648 /* Convert the user. */ 1649 usrdatum = hashtab_search(args->newp->p_users.table, 1650 args->oldp->p_user_val_to_name[c->user - 1]); 1651 if (!usrdatum) 1652 goto bad; 1653 c->user = usrdatum->value; 1654 1655 /* Convert the role. */ 1656 role = hashtab_search(args->newp->p_roles.table, 1657 args->oldp->p_role_val_to_name[c->role - 1]); 1658 if (!role) 1659 goto bad; 1660 c->role = role->value; 1661 1662 /* Convert the type. */ 1663 typdatum = hashtab_search(args->newp->p_types.table, 1664 args->oldp->p_type_val_to_name[c->type - 1]); 1665 if (!typdatum) 1666 goto bad; 1667 c->type = typdatum->value; 1668 1669 /* Convert the MLS fields if dealing with MLS policies */ 1670 if (args->oldp->mls_enabled && args->newp->mls_enabled) { 1671 rc = mls_convert_context(args->oldp, args->newp, c); 1672 if (rc) 1673 goto bad; 1674 } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { 1675 /* 1676 * Switching between MLS and non-MLS policy: 1677 * free any storage used by the MLS fields in the 1678 * context for all existing entries in the sidtab. 1679 */ 1680 mls_context_destroy(c); 1681 } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { 1682 /* 1683 * Switching between non-MLS and MLS policy: 1684 * ensure that the MLS fields of the context for all 1685 * existing entries in the sidtab are filled in with a 1686 * suitable default value, likely taken from one of the 1687 * initial SIDs. 1688 */ 1689 oc = args->newp->ocontexts[OCON_ISID]; 1690 while (oc && oc->sid[0] != SECINITSID_UNLABELED) 1691 oc = oc->next; 1692 if (!oc) { 1693 printk(KERN_ERR "SELinux: unable to look up" 1694 " the initial SIDs list\n"); 1695 goto bad; 1696 } 1697 range = &oc->context[0].range; 1698 rc = mls_range_set(c, range); 1699 if (rc) 1700 goto bad; 1701 } 1702 1703 /* Check the validity of the new context. */ 1704 if (!policydb_context_isvalid(args->newp, c)) { 1705 rc = convert_context_handle_invalid_context(&oldc); 1706 if (rc) 1707 goto bad; 1708 } 1709 1710 context_destroy(&oldc); 1711 rc = 0; 1712out: 1713 return rc; 1714bad: 1715 /* Map old representation to string and save it. */ 1716 if (context_struct_to_string(&oldc, &s, &len)) 1717 return -ENOMEM; 1718 context_destroy(&oldc); 1719 context_destroy(c); 1720 c->str = s; 1721 c->len = len; 1722 printk(KERN_INFO 1723 "SELinux: Context %s became invalid (unmapped).\n", 1724 c->str); 1725 rc = 0; 1726 goto out; 1727} 1728 1729static void security_load_policycaps(void) 1730{ 1731 selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps, 1732 POLICYDB_CAPABILITY_NETPEER); 1733 selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps, 1734 POLICYDB_CAPABILITY_OPENPERM); 1735} 1736 1737extern void selinux_complete_init(void); 1738static int security_preserve_bools(struct policydb *p); 1739 1740/** 1741 * security_load_policy - Load a security policy configuration. 1742 * @data: binary policy data 1743 * @len: length of data in bytes 1744 * 1745 * Load a new set of security policy configuration data, 1746 * validate it and convert the SID table as necessary. 1747 * This function will flush the access vector cache after 1748 * loading the new policy. 1749 */ 1750int security_load_policy(void *data, size_t len) 1751{ 1752 struct policydb oldpolicydb, newpolicydb; 1753 struct sidtab oldsidtab, newsidtab; 1754 struct selinux_mapping *oldmap, *map = NULL; 1755 struct convert_context_args args; 1756 u32 seqno; 1757 u16 map_size; 1758 int rc = 0; 1759 struct policy_file file = { data, len }, *fp = &file; 1760 1761 if (!ss_initialized) { 1762 avtab_cache_init(); 1763 rc = policydb_read(&policydb, fp); 1764 if (rc) { 1765 avtab_cache_destroy(); 1766 return rc; 1767 } 1768 1769 rc = selinux_set_mapping(&policydb, secclass_map, 1770 ¤t_mapping, 1771 ¤t_mapping_size); 1772 if (rc) { 1773 policydb_destroy(&policydb); 1774 avtab_cache_destroy(); 1775 return rc; 1776 } 1777 1778 rc = policydb_load_isids(&policydb, &sidtab); 1779 if (rc) { 1780 policydb_destroy(&policydb); 1781 avtab_cache_destroy(); 1782 return rc; 1783 } 1784 1785 security_load_policycaps(); 1786 ss_initialized = 1; 1787 seqno = ++latest_granting; 1788 selinux_complete_init(); 1789 avc_ss_reset(seqno); 1790 selnl_notify_policyload(seqno); 1791 selinux_netlbl_cache_invalidate(); 1792 selinux_xfrm_notify_policyload(); 1793 return 0; 1794 } 1795 1796#if 0 1797 sidtab_hash_eval(&sidtab, "sids"); 1798#endif 1799 1800 rc = policydb_read(&newpolicydb, fp); 1801 if (rc) 1802 return rc; 1803 1804 /* If switching between different policy types, log MLS status */ 1805 if (policydb.mls_enabled && !newpolicydb.mls_enabled) 1806 printk(KERN_INFO "SELinux: Disabling MLS support...\n"); 1807 else if (!policydb.mls_enabled && newpolicydb.mls_enabled) 1808 printk(KERN_INFO "SELinux: Enabling MLS support...\n"); 1809 1810 rc = policydb_load_isids(&newpolicydb, &newsidtab); 1811 if (rc) { 1812 printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); 1813 policydb_destroy(&newpolicydb); 1814 return rc; 1815 } 1816 1817 rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size); 1818 if (rc) 1819 goto err; 1820 1821 rc = security_preserve_bools(&newpolicydb); 1822 if (rc) { 1823 printk(KERN_ERR "SELinux: unable to preserve booleans\n"); 1824 goto err; 1825 } 1826 1827 /* Clone the SID table. */ 1828 sidtab_shutdown(&sidtab); 1829 1830 rc = sidtab_map(&sidtab, clone_sid, &newsidtab); 1831 if (rc) 1832 goto err; 1833 1834 /* 1835 * Convert the internal representations of contexts 1836 * in the new SID table. 1837 */ 1838 args.oldp = &policydb; 1839 args.newp = &newpolicydb; 1840 rc = sidtab_map(&newsidtab, convert_context, &args); 1841 if (rc) { 1842 printk(KERN_ERR "SELinux: unable to convert the internal" 1843 " representation of contexts in the new SID" 1844 " table\n"); 1845 goto err; 1846 } 1847 1848 /* Save the old policydb and SID table to free later. */ 1849 memcpy(&oldpolicydb, &policydb, sizeof policydb); 1850 sidtab_set(&oldsidtab, &sidtab); 1851 1852 /* Install the new policydb and SID table. */ 1853 write_lock_irq(&policy_rwlock); 1854 memcpy(&policydb, &newpolicydb, sizeof policydb); 1855 sidtab_set(&sidtab, &newsidtab); 1856 security_load_policycaps(); 1857 oldmap = current_mapping; 1858 current_mapping = map; 1859 current_mapping_size = map_size; 1860 seqno = ++latest_granting; 1861 write_unlock_irq(&policy_rwlock); 1862 1863 /* Free the old policydb and SID table. */ 1864 policydb_destroy(&oldpolicydb); 1865 sidtab_destroy(&oldsidtab); 1866 kfree(oldmap); 1867 1868 avc_ss_reset(seqno); 1869 selnl_notify_policyload(seqno); 1870 selinux_netlbl_cache_invalidate(); 1871 selinux_xfrm_notify_policyload(); 1872 1873 return 0; 1874 1875err: 1876 kfree(map); 1877 sidtab_destroy(&newsidtab); 1878 policydb_destroy(&newpolicydb); 1879 return rc; 1880 1881} 1882 1883/** 1884 * security_port_sid - Obtain the SID for a port. 1885 * @protocol: protocol number 1886 * @port: port number 1887 * @out_sid: security identifier 1888 */ 1889int security_port_sid(u8 protocol, u16 port, u32 *out_sid) 1890{ 1891 struct ocontext *c; 1892 int rc = 0; 1893 1894 read_lock(&policy_rwlock); 1895 1896 c = policydb.ocontexts[OCON_PORT]; 1897 while (c) { 1898 if (c->u.port.protocol == protocol && 1899 c->u.port.low_port <= port && 1900 c->u.port.high_port >= port) 1901 break; 1902 c = c->next; 1903 } 1904 1905 if (c) { 1906 if (!c->sid[0]) { 1907 rc = sidtab_context_to_sid(&sidtab, 1908 &c->context[0], 1909 &c->sid[0]); 1910 if (rc) 1911 goto out; 1912 } 1913 *out_sid = c->sid[0]; 1914 } else { 1915 *out_sid = SECINITSID_PORT; 1916 } 1917 1918out: 1919 read_unlock(&policy_rwlock); 1920 return rc; 1921} 1922 1923/** 1924 * security_netif_sid - Obtain the SID for a network interface. 1925 * @name: interface name 1926 * @if_sid: interface SID 1927 */ 1928int security_netif_sid(char *name, u32 *if_sid) 1929{ 1930 int rc = 0; 1931 struct ocontext *c; 1932 1933 read_lock(&policy_rwlock); 1934 1935 c = policydb.ocontexts[OCON_NETIF]; 1936 while (c) { 1937 if (strcmp(name, c->u.name) == 0) 1938 break; 1939 c = c->next; 1940 } 1941 1942 if (c) { 1943 if (!c->sid[0] || !c->sid[1]) { 1944 rc = sidtab_context_to_sid(&sidtab, 1945 &c->context[0], 1946 &c->sid[0]); 1947 if (rc) 1948 goto out; 1949 rc = sidtab_context_to_sid(&sidtab, 1950 &c->context[1], 1951 &c->sid[1]); 1952 if (rc) 1953 goto out; 1954 } 1955 *if_sid = c->sid[0]; 1956 } else 1957 *if_sid = SECINITSID_NETIF; 1958 1959out: 1960 read_unlock(&policy_rwlock); 1961 return rc; 1962} 1963 1964static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) 1965{ 1966 int i, fail = 0; 1967 1968 for (i = 0; i < 4; i++) 1969 if (addr[i] != (input[i] & mask[i])) { 1970 fail = 1; 1971 break; 1972 } 1973 1974 return !fail; 1975} 1976 1977/** 1978 * security_node_sid - Obtain the SID for a node (host). 1979 * @domain: communication domain aka address family 1980 * @addrp: address 1981 * @addrlen: address length in bytes 1982 * @out_sid: security identifier 1983 */ 1984int security_node_sid(u16 domain, 1985 void *addrp, 1986 u32 addrlen, 1987 u32 *out_sid) 1988{ 1989 int rc = 0; 1990 struct ocontext *c; 1991 1992 read_lock(&policy_rwlock); 1993 1994 switch (domain) { 1995 case AF_INET: { 1996 u32 addr; 1997 1998 if (addrlen != sizeof(u32)) { 1999 rc = -EINVAL; 2000 goto out; 2001 } 2002 2003 addr = *((u32 *)addrp); 2004 2005 c = policydb.ocontexts[OCON_NODE]; 2006 while (c) { 2007 if (c->u.node.addr == (addr & c->u.node.mask)) 2008 break; 2009 c = c->next; 2010 } 2011 break; 2012 } 2013 2014 case AF_INET6: 2015 if (addrlen != sizeof(u64) * 2) { 2016 rc = -EINVAL; 2017 goto out; 2018 } 2019 c = policydb.ocontexts[OCON_NODE6]; 2020 while (c) { 2021 if (match_ipv6_addrmask(addrp, c->u.node6.addr, 2022 c->u.node6.mask)) 2023 break; 2024 c = c->next; 2025 } 2026 break; 2027 2028 default: 2029 *out_sid = SECINITSID_NODE; 2030 goto out; 2031 } 2032 2033 if (c) { 2034 if (!c->sid[0]) { 2035 rc = sidtab_context_to_sid(&sidtab, 2036 &c->context[0], 2037 &c->sid[0]); 2038 if (rc) 2039 goto out; 2040 } 2041 *out_sid = c->sid[0]; 2042 } else { 2043 *out_sid = SECINITSID_NODE; 2044 } 2045 2046out: 2047 read_unlock(&policy_rwlock); 2048 return rc; 2049} 2050 2051#define SIDS_NEL 25 2052 2053/** 2054 * security_get_user_sids - Obtain reachable SIDs for a user. 2055 * @fromsid: starting SID 2056 * @username: username 2057 * @sids: array of reachable SIDs for user 2058 * @nel: number of elements in @sids 2059 * 2060 * Generate the set of SIDs for legal security contexts 2061 * for a given user that can be reached by @fromsid. 2062 * Set *@sids to point to a dynamically allocated 2063 * array containing the set of SIDs. Set *@nel to the 2064 * number of elements in the array. 2065 */ 2066 2067int security_get_user_sids(u32 fromsid, 2068 char *username, 2069 u32 **sids, 2070 u32 *nel) 2071{ 2072 struct context *fromcon, usercon; 2073 u32 *mysids = NULL, *mysids2, sid; 2074 u32 mynel = 0, maxnel = SIDS_NEL; 2075 struct user_datum *user; 2076 struct role_datum *role; 2077 struct ebitmap_node *rnode, *tnode; 2078 int rc = 0, i, j; 2079 2080 *sids = NULL; 2081 *nel = 0; 2082 2083 if (!ss_initialized) 2084 goto out; 2085 2086 read_lock(&policy_rwlock); 2087 2088 context_init(&usercon); 2089 2090 fromcon = sidtab_search(&sidtab, fromsid); 2091 if (!fromcon) { 2092 rc = -EINVAL; 2093 goto out_unlock; 2094 } 2095 2096 user = hashtab_search(policydb.p_users.table, username); 2097 if (!user) { 2098 rc = -EINVAL; 2099 goto out_unlock; 2100 } 2101 usercon.user = user->value; 2102 2103 mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); 2104 if (!mysids) { 2105 rc = -ENOMEM; 2106 goto out_unlock; 2107 } 2108 2109 ebitmap_for_each_positive_bit(&user->roles, rnode, i) { 2110 role = policydb.role_val_to_struct[i]; 2111 usercon.role = i + 1; 2112 ebitmap_for_each_positive_bit(&role->types, tnode, j) { 2113 usercon.type = j + 1; 2114 2115 if (mls_setup_user_range(fromcon, user, &usercon)) 2116 continue; 2117 2118 rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); 2119 if (rc) 2120 goto out_unlock; 2121 if (mynel < maxnel) { 2122 mysids[mynel++] = sid; 2123 } else { 2124 maxnel += SIDS_NEL; 2125 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); 2126 if (!mysids2) { 2127 rc = -ENOMEM; 2128 goto out_unlock; 2129 } 2130 memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); 2131 kfree(mysids); 2132 mysids = mysids2; 2133 mysids[mynel++] = sid; 2134 } 2135 } 2136 } 2137 2138out_unlock: 2139 read_unlock(&policy_rwlock); 2140 if (rc || !mynel) { 2141 kfree(mysids); 2142 goto out; 2143 } 2144 2145 mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); 2146 if (!mysids2) { 2147 rc = -ENOMEM; 2148 kfree(mysids); 2149 goto out; 2150 } 2151 for (i = 0, j = 0; i < mynel; i++) { 2152 rc = avc_has_perm_noaudit(fromsid, mysids[i], 2153 SECCLASS_PROCESS, /* kernel value */ 2154 PROCESS__TRANSITION, AVC_STRICT, 2155 NULL); 2156 if (!rc) 2157 mysids2[j++] = mysids[i]; 2158 cond_resched(); 2159 } 2160 rc = 0; 2161 kfree(mysids); 2162 *sids = mysids2; 2163 *nel = j; 2164out: 2165 return rc; 2166} 2167 2168/** 2169 * security_genfs_sid - Obtain a SID for a file in a filesystem 2170 * @fstype: filesystem type 2171 * @path: path from root of mount 2172 * @sclass: file security class 2173 * @sid: SID for path 2174 * 2175 * Obtain a SID to use for a file in a filesystem that 2176 * cannot support xattr or use a fixed labeling behavior like 2177 * transition SIDs or task SIDs. 2178 */ 2179int security_genfs_sid(const char *fstype, 2180 char *path, 2181 u16 orig_sclass, 2182 u32 *sid) 2183{ 2184 int len; 2185 u16 sclass; 2186 struct genfs *genfs; 2187 struct ocontext *c; 2188 int rc = 0, cmp = 0; 2189 2190 while (path[0] == '/' && path[1] == '/') 2191 path++; 2192 2193 read_lock(&policy_rwlock); 2194 2195 sclass = unmap_class(orig_sclass); 2196 2197 for (genfs = policydb.genfs; genfs; genfs = genfs->next) { 2198 cmp = strcmp(fstype, genfs->fstype); 2199 if (cmp <= 0) 2200 break; 2201 } 2202 2203 if (!genfs || cmp) { 2204 *sid = SECINITSID_UNLABELED; 2205 rc = -ENOENT; 2206 goto out; 2207 } 2208 2209 for (c = genfs->head; c; c = c->next) { 2210 len = strlen(c->u.name); 2211 if ((!c->v.sclass || sclass == c->v.sclass) && 2212 (strncmp(c->u.name, path, len) == 0)) 2213 break; 2214 } 2215 2216 if (!c) { 2217 *sid = SECINITSID_UNLABELED; 2218 rc = -ENOENT; 2219 goto out; 2220 } 2221 2222 if (!c->sid[0]) { 2223 rc = sidtab_context_to_sid(&sidtab, 2224 &c->context[0], 2225 &c->sid[0]); 2226 if (rc) 2227 goto out; 2228 } 2229 2230 *sid = c->sid[0]; 2231out: 2232 read_unlock(&policy_rwlock); 2233 return rc; 2234} 2235 2236/** 2237 * security_fs_use - Determine how to handle labeling for a filesystem. 2238 * @fstype: filesystem type 2239 * @behavior: labeling behavior 2240 * @sid: SID for filesystem (superblock) 2241 */ 2242int security_fs_use( 2243 const char *fstype, 2244 unsigned int *behavior, 2245 u32 *sid) 2246{ 2247 int rc = 0; 2248 struct ocontext *c; 2249 2250 read_lock(&policy_rwlock); 2251 2252 c = policydb.ocontexts[OCON_FSUSE]; 2253 while (c) { 2254 if (strcmp(fstype, c->u.name) == 0) 2255 break; 2256 c = c->next; 2257 } 2258 2259 if (c) { 2260 *behavior = c->v.behavior; 2261 if (!c->sid[0]) { 2262 rc = sidtab_context_to_sid(&sidtab, 2263 &c->context[0], 2264 &c->sid[0]); 2265 if (rc) 2266 goto out; 2267 } 2268 *sid = c->sid[0]; 2269 } else { 2270 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid); 2271 if (rc) { 2272 *behavior = SECURITY_FS_USE_NONE; 2273 rc = 0; 2274 } else { 2275 *behavior = SECURITY_FS_USE_GENFS; 2276 } 2277 } 2278 2279out: 2280 read_unlock(&policy_rwlock); 2281 return rc; 2282} 2283 2284int security_get_bools(int *len, char ***names, int **values) 2285{ 2286 int i, rc = -ENOMEM; 2287 2288 read_lock(&policy_rwlock); 2289 *names = NULL; 2290 *values = NULL; 2291 2292 *len = policydb.p_bools.nprim; 2293 if (!*len) { 2294 rc = 0; 2295 goto out; 2296 } 2297 2298 *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); 2299 if (!*names) 2300 goto err; 2301 2302 *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); 2303 if (!*values) 2304 goto err; 2305 2306 for (i = 0; i < *len; i++) { 2307 size_t name_len; 2308 (*values)[i] = policydb.bool_val_to_struct[i]->state; 2309 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1; 2310 (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC); 2311 if (!(*names)[i]) 2312 goto err; 2313 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len); 2314 (*names)[i][name_len - 1] = 0; 2315 } 2316 rc = 0; 2317out: 2318 read_unlock(&policy_rwlock); 2319 return rc; 2320err: 2321 if (*names) { 2322 for (i = 0; i < *len; i++) 2323 kfree((*names)[i]); 2324 } 2325 kfree(*values); 2326 goto out; 2327} 2328 2329 2330int security_set_bools(int len, int *values) 2331{ 2332 int i, rc = 0; 2333 int lenp, seqno = 0; 2334 struct cond_node *cur; 2335 2336 write_lock_irq(&policy_rwlock); 2337 2338 lenp = policydb.p_bools.nprim; 2339 if (len != lenp) { 2340 rc = -EFAULT; 2341 goto out; 2342 } 2343 2344 for (i = 0; i < len; i++) { 2345 if (!!values[i] != policydb.bool_val_to_struct[i]->state) { 2346 audit_log(current->audit_context, GFP_ATOMIC, 2347 AUDIT_MAC_CONFIG_CHANGE, 2348 "bool=%s val=%d old_val=%d auid=%u ses=%u", 2349 policydb.p_bool_val_to_name[i], 2350 !!values[i], 2351 policydb.bool_val_to_struct[i]->state, 2352 audit_get_loginuid(current), 2353 audit_get_sessionid(current)); 2354 } 2355 if (values[i]) 2356 policydb.bool_val_to_struct[i]->state = 1; 2357 else 2358 policydb.bool_val_to_struct[i]->state = 0; 2359 } 2360 2361 for (cur = policydb.cond_list; cur; cur = cur->next) { 2362 rc = evaluate_cond_node(&policydb, cur); 2363 if (rc) 2364 goto out; 2365 } 2366 2367 seqno = ++latest_granting; 2368 2369out: 2370 write_unlock_irq(&policy_rwlock); 2371 if (!rc) { 2372 avc_ss_reset(seqno); 2373 selnl_notify_policyload(seqno); 2374 selinux_xfrm_notify_policyload(); 2375 } 2376 return rc; 2377} 2378 2379int security_get_bool_value(int bool) 2380{ 2381 int rc = 0; 2382 int len; 2383 2384 read_lock(&policy_rwlock); 2385 2386 len = policydb.p_bools.nprim; 2387 if (bool >= len) { 2388 rc = -EFAULT; 2389 goto out; 2390 } 2391 2392 rc = policydb.bool_val_to_struct[bool]->state; 2393out: 2394 read_unlock(&policy_rwlock); 2395 return rc; 2396} 2397 2398static int security_preserve_bools(struct policydb *p) 2399{ 2400 int rc, nbools = 0, *bvalues = NULL, i; 2401 char **bnames = NULL; 2402 struct cond_bool_datum *booldatum; 2403 struct cond_node *cur; 2404 2405 rc = security_get_bools(&nbools, &bnames, &bvalues); 2406 if (rc) 2407 goto out; 2408 for (i = 0; i < nbools; i++) { 2409 booldatum = hashtab_search(p->p_bools.table, bnames[i]); 2410 if (booldatum) 2411 booldatum->state = bvalues[i]; 2412 } 2413 for (cur = p->cond_list; cur; cur = cur->next) { 2414 rc = evaluate_cond_node(p, cur); 2415 if (rc) 2416 goto out; 2417 } 2418 2419out: 2420 if (bnames) { 2421 for (i = 0; i < nbools; i++) 2422 kfree(bnames[i]); 2423 } 2424 kfree(bnames); 2425 kfree(bvalues); 2426 return rc; 2427} 2428 2429/* 2430 * security_sid_mls_copy() - computes a new sid based on the given 2431 * sid and the mls portion of mls_sid. 2432 */ 2433int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid) 2434{ 2435 struct context *context1; 2436 struct context *context2; 2437 struct context newcon; 2438 char *s; 2439 u32 len; 2440 int rc = 0; 2441 2442 if (!ss_initialized || !policydb.mls_enabled) { 2443 *new_sid = sid; 2444 goto out; 2445 } 2446 2447 context_init(&newcon); 2448 2449 read_lock(&policy_rwlock); 2450 context1 = sidtab_search(&sidtab, sid); 2451 if (!context1) { 2452 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2453 __func__, sid); 2454 rc = -EINVAL; 2455 goto out_unlock; 2456 } 2457 2458 context2 = sidtab_search(&sidtab, mls_sid); 2459 if (!context2) { 2460 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2461 __func__, mls_sid); 2462 rc = -EINVAL; 2463 goto out_unlock; 2464 } 2465 2466 newcon.user = context1->user; 2467 newcon.role = context1->role; 2468 newcon.type = context1->type; 2469 rc = mls_context_cpy(&newcon, context2); 2470 if (rc) 2471 goto out_unlock; 2472 2473 /* Check the validity of the new context. */ 2474 if (!policydb_context_isvalid(&policydb, &newcon)) { 2475 rc = convert_context_handle_invalid_context(&newcon); 2476 if (rc) 2477 goto bad; 2478 } 2479 2480 rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid); 2481 goto out_unlock; 2482 2483bad: 2484 if (!context_struct_to_string(&newcon, &s, &len)) { 2485 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2486 "security_sid_mls_copy: invalid context %s", s); 2487 kfree(s); 2488 } 2489 2490out_unlock: 2491 read_unlock(&policy_rwlock); 2492 context_destroy(&newcon); 2493out: 2494 return rc; 2495} 2496 2497/** 2498 * security_net_peersid_resolve - Compare and resolve two network peer SIDs 2499 * @nlbl_sid: NetLabel SID 2500 * @nlbl_type: NetLabel labeling protocol type 2501 * @xfrm_sid: XFRM SID 2502 * 2503 * Description: 2504 * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be 2505 * resolved into a single SID it is returned via @peer_sid and the function 2506 * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function 2507 * returns a negative value. A table summarizing the behavior is below: 2508 * 2509 * | function return | @sid 2510 * ------------------------------+-----------------+----------------- 2511 * no peer labels | 0 | SECSID_NULL 2512 * single peer label | 0 | <peer_label> 2513 * multiple, consistent labels | 0 | <peer_label> 2514 * multiple, inconsistent labels | -<errno> | SECSID_NULL 2515 * 2516 */ 2517int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type, 2518 u32 xfrm_sid, 2519 u32 *peer_sid) 2520{ 2521 int rc; 2522 struct context *nlbl_ctx; 2523 struct context *xfrm_ctx; 2524 2525 /* handle the common (which also happens to be the set of easy) cases 2526 * right away, these two if statements catch everything involving a 2527 * single or absent peer SID/label */ 2528 if (xfrm_sid == SECSID_NULL) { 2529 *peer_sid = nlbl_sid; 2530 return 0; 2531 } 2532 /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label 2533 * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label 2534 * is present */ 2535 if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { 2536 *peer_sid = xfrm_sid; 2537 return 0; 2538 } 2539 2540 /* we don't need to check ss_initialized here since the only way both 2541 * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the 2542 * security server was initialized and ss_initialized was true */ 2543 if (!policydb.mls_enabled) { 2544 *peer_sid = SECSID_NULL; 2545 return 0; 2546 } 2547 2548 read_lock(&policy_rwlock); 2549 2550 nlbl_ctx = sidtab_search(&sidtab, nlbl_sid); 2551 if (!nlbl_ctx) { 2552 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2553 __func__, nlbl_sid); 2554 rc = -EINVAL; 2555 goto out_slowpath; 2556 } 2557 xfrm_ctx = sidtab_search(&sidtab, xfrm_sid); 2558 if (!xfrm_ctx) { 2559 printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", 2560 __func__, xfrm_sid); 2561 rc = -EINVAL; 2562 goto out_slowpath; 2563 } 2564 rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); 2565 2566out_slowpath: 2567 read_unlock(&policy_rwlock); 2568 if (rc == 0) 2569 /* at present NetLabel SIDs/labels really only carry MLS 2570 * information so if the MLS portion of the NetLabel SID 2571 * matches the MLS portion of the labeled XFRM SID/label 2572 * then pass along the XFRM SID as it is the most 2573 * expressive */ 2574 *peer_sid = xfrm_sid; 2575 else 2576 *peer_sid = SECSID_NULL; 2577 return rc; 2578} 2579 2580static int get_classes_callback(void *k, void *d, void *args) 2581{ 2582 struct class_datum *datum = d; 2583 char *name = k, **classes = args; 2584 int value = datum->value - 1; 2585 2586 classes[value] = kstrdup(name, GFP_ATOMIC); 2587 if (!classes[value]) 2588 return -ENOMEM; 2589 2590 return 0; 2591} 2592 2593int security_get_classes(char ***classes, int *nclasses) 2594{ 2595 int rc = -ENOMEM; 2596 2597 read_lock(&policy_rwlock); 2598 2599 *nclasses = policydb.p_classes.nprim; 2600 *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); 2601 if (!*classes) 2602 goto out; 2603 2604 rc = hashtab_map(policydb.p_classes.table, get_classes_callback, 2605 *classes); 2606 if (rc < 0) { 2607 int i; 2608 for (i = 0; i < *nclasses; i++) 2609 kfree((*classes)[i]); 2610 kfree(*classes); 2611 } 2612 2613out: 2614 read_unlock(&policy_rwlock); 2615 return rc; 2616} 2617 2618static int get_permissions_callback(void *k, void *d, void *args) 2619{ 2620 struct perm_datum *datum = d; 2621 char *name = k, **perms = args; 2622 int value = datum->value - 1; 2623 2624 perms[value] = kstrdup(name, GFP_ATOMIC); 2625 if (!perms[value]) 2626 return -ENOMEM; 2627 2628 return 0; 2629} 2630 2631int security_get_permissions(char *class, char ***perms, int *nperms) 2632{ 2633 int rc = -ENOMEM, i; 2634 struct class_datum *match; 2635 2636 read_lock(&policy_rwlock); 2637 2638 match = hashtab_search(policydb.p_classes.table, class); 2639 if (!match) { 2640 printk(KERN_ERR "SELinux: %s: unrecognized class %s\n", 2641 __func__, class); 2642 rc = -EINVAL; 2643 goto out; 2644 } 2645 2646 *nperms = match->permissions.nprim; 2647 *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); 2648 if (!*perms) 2649 goto out; 2650 2651 if (match->comdatum) { 2652 rc = hashtab_map(match->comdatum->permissions.table, 2653 get_permissions_callback, *perms); 2654 if (rc < 0) 2655 goto err; 2656 } 2657 2658 rc = hashtab_map(match->permissions.table, get_permissions_callback, 2659 *perms); 2660 if (rc < 0) 2661 goto err; 2662 2663out: 2664 read_unlock(&policy_rwlock); 2665 return rc; 2666 2667err: 2668 read_unlock(&policy_rwlock); 2669 for (i = 0; i < *nperms; i++) 2670 kfree((*perms)[i]); 2671 kfree(*perms); 2672 return rc; 2673} 2674 2675int security_get_reject_unknown(void) 2676{ 2677 return policydb.reject_unknown; 2678} 2679 2680int security_get_allow_unknown(void) 2681{ 2682 return policydb.allow_unknown; 2683} 2684 2685/** 2686 * security_policycap_supported - Check for a specific policy capability 2687 * @req_cap: capability 2688 * 2689 * Description: 2690 * This function queries the currently loaded policy to see if it supports the 2691 * capability specified by @req_cap. Returns true (1) if the capability is 2692 * supported, false (0) if it isn't supported. 2693 * 2694 */ 2695int security_policycap_supported(unsigned int req_cap) 2696{ 2697 int rc; 2698 2699 read_lock(&policy_rwlock); 2700 rc = ebitmap_get_bit(&policydb.policycaps, req_cap); 2701 read_unlock(&policy_rwlock); 2702 2703 return rc; 2704} 2705 2706struct selinux_audit_rule { 2707 u32 au_seqno; 2708 struct context au_ctxt; 2709}; 2710 2711void selinux_audit_rule_free(void *vrule) 2712{ 2713 struct selinux_audit_rule *rule = vrule; 2714 2715 if (rule) { 2716 context_destroy(&rule->au_ctxt); 2717 kfree(rule); 2718 } 2719} 2720 2721int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) 2722{ 2723 struct selinux_audit_rule *tmprule; 2724 struct role_datum *roledatum; 2725 struct type_datum *typedatum; 2726 struct user_datum *userdatum; 2727 struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; 2728 int rc = 0; 2729 2730 *rule = NULL; 2731 2732 if (!ss_initialized) 2733 return -EOPNOTSUPP; 2734 2735 switch (field) { 2736 case AUDIT_SUBJ_USER: 2737 case AUDIT_SUBJ_ROLE: 2738 case AUDIT_SUBJ_TYPE: 2739 case AUDIT_OBJ_USER: 2740 case AUDIT_OBJ_ROLE: 2741 case AUDIT_OBJ_TYPE: 2742 /* only 'equals' and 'not equals' fit user, role, and type */ 2743 if (op != Audit_equal && op != Audit_not_equal) 2744 return -EINVAL; 2745 break; 2746 case AUDIT_SUBJ_SEN: 2747 case AUDIT_SUBJ_CLR: 2748 case AUDIT_OBJ_LEV_LOW: 2749 case AUDIT_OBJ_LEV_HIGH: 2750 /* we do not allow a range, indicated by the presense of '-' */ 2751 if (strchr(rulestr, '-')) 2752 return -EINVAL; 2753 break; 2754 default: 2755 /* only the above fields are valid */ 2756 return -EINVAL; 2757 } 2758 2759 tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); 2760 if (!tmprule) 2761 return -ENOMEM; 2762 2763 context_init(&tmprule->au_ctxt); 2764 2765 read_lock(&policy_rwlock); 2766 2767 tmprule->au_seqno = latest_granting; 2768 2769 switch (field) { 2770 case AUDIT_SUBJ_USER: 2771 case AUDIT_OBJ_USER: 2772 userdatum = hashtab_search(policydb.p_users.table, rulestr); 2773 if (!userdatum) 2774 rc = -EINVAL; 2775 else 2776 tmprule->au_ctxt.user = userdatum->value; 2777 break; 2778 case AUDIT_SUBJ_ROLE: 2779 case AUDIT_OBJ_ROLE: 2780 roledatum = hashtab_search(policydb.p_roles.table, rulestr); 2781 if (!roledatum) 2782 rc = -EINVAL; 2783 else 2784 tmprule->au_ctxt.role = roledatum->value; 2785 break; 2786 case AUDIT_SUBJ_TYPE: 2787 case AUDIT_OBJ_TYPE: 2788 typedatum = hashtab_search(policydb.p_types.table, rulestr); 2789 if (!typedatum) 2790 rc = -EINVAL; 2791 else 2792 tmprule->au_ctxt.type = typedatum->value; 2793 break; 2794 case AUDIT_SUBJ_SEN: 2795 case AUDIT_SUBJ_CLR: 2796 case AUDIT_OBJ_LEV_LOW: 2797 case AUDIT_OBJ_LEV_HIGH: 2798 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC); 2799 break; 2800 } 2801 2802 read_unlock(&policy_rwlock); 2803 2804 if (rc) { 2805 selinux_audit_rule_free(tmprule); 2806 tmprule = NULL; 2807 } 2808 2809 *rule = tmprule; 2810 2811 return rc; 2812} 2813 2814/* Check to see if the rule contains any selinux fields */ 2815int selinux_audit_rule_known(struct audit_krule *rule) 2816{ 2817 int i; 2818 2819 for (i = 0; i < rule->field_count; i++) { 2820 struct audit_field *f = &rule->fields[i]; 2821 switch (f->type) { 2822 case AUDIT_SUBJ_USER: 2823 case AUDIT_SUBJ_ROLE: 2824 case AUDIT_SUBJ_TYPE: 2825 case AUDIT_SUBJ_SEN: 2826 case AUDIT_SUBJ_CLR: 2827 case AUDIT_OBJ_USER: 2828 case AUDIT_OBJ_ROLE: 2829 case AUDIT_OBJ_TYPE: 2830 case AUDIT_OBJ_LEV_LOW: 2831 case AUDIT_OBJ_LEV_HIGH: 2832 return 1; 2833 } 2834 } 2835 2836 return 0; 2837} 2838 2839int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, 2840 struct audit_context *actx) 2841{ 2842 struct context *ctxt; 2843 struct mls_level *level; 2844 struct selinux_audit_rule *rule = vrule; 2845 int match = 0; 2846 2847 if (!rule) { 2848 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2849 "selinux_audit_rule_match: missing rule\n"); 2850 return -ENOENT; 2851 } 2852 2853 read_lock(&policy_rwlock); 2854 2855 if (rule->au_seqno < latest_granting) { 2856 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2857 "selinux_audit_rule_match: stale rule\n"); 2858 match = -ESTALE; 2859 goto out; 2860 } 2861 2862 ctxt = sidtab_search(&sidtab, sid); 2863 if (!ctxt) { 2864 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, 2865 "selinux_audit_rule_match: unrecognized SID %d\n", 2866 sid); 2867 match = -ENOENT; 2868 goto out; 2869 } 2870 2871 /* a field/op pair that is not caught here will simply fall through 2872 without a match */ 2873 switch (field) { 2874 case AUDIT_SUBJ_USER: 2875 case AUDIT_OBJ_USER: 2876 switch (op) { 2877 case Audit_equal: 2878 match = (ctxt->user == rule->au_ctxt.user); 2879 break; 2880 case Audit_not_equal: 2881 match = (ctxt->user != rule->au_ctxt.user); 2882 break; 2883 } 2884 break; 2885 case AUDIT_SUBJ_ROLE: 2886 case AUDIT_OBJ_ROLE: 2887 switch (op) { 2888 case Audit_equal: 2889 match = (ctxt->role == rule->au_ctxt.role); 2890 break; 2891 case Audit_not_equal: 2892 match = (ctxt->role != rule->au_ctxt.role); 2893 break; 2894 } 2895 break; 2896 case AUDIT_SUBJ_TYPE: 2897 case AUDIT_OBJ_TYPE: 2898 switch (op) { 2899 case Audit_equal: 2900 match = (ctxt->type == rule->au_ctxt.type); 2901 break; 2902 case Audit_not_equal: 2903 match = (ctxt->type != rule->au_ctxt.type); 2904 break; 2905 } 2906 break; 2907 case AUDIT_SUBJ_SEN: 2908 case AUDIT_SUBJ_CLR: 2909 case AUDIT_OBJ_LEV_LOW: 2910 case AUDIT_OBJ_LEV_HIGH: 2911 level = ((field == AUDIT_SUBJ_SEN || 2912 field == AUDIT_OBJ_LEV_LOW) ? 2913 &ctxt->range.level[0] : &ctxt->range.level[1]); 2914 switch (op) { 2915 case Audit_equal: 2916 match = mls_level_eq(&rule->au_ctxt.range.level[0], 2917 level); 2918 break; 2919 case Audit_not_equal: 2920 match = !mls_level_eq(&rule->au_ctxt.range.level[0], 2921 level); 2922 break; 2923 case Audit_lt: 2924 match = (mls_level_dom(&rule->au_ctxt.range.level[0], 2925 level) && 2926 !mls_level_eq(&rule->au_ctxt.range.level[0], 2927 level)); 2928 break; 2929 case Audit_le: 2930 match = mls_level_dom(&rule->au_ctxt.range.level[0], 2931 level); 2932 break; 2933 case Audit_gt: 2934 match = (mls_level_dom(level, 2935 &rule->au_ctxt.range.level[0]) && 2936 !mls_level_eq(level, 2937 &rule->au_ctxt.range.level[0])); 2938 break; 2939 case Audit_ge: 2940 match = mls_level_dom(level, 2941 &rule->au_ctxt.range.level[0]); 2942 break; 2943 } 2944 } 2945 2946out: 2947 read_unlock(&policy_rwlock); 2948 return match; 2949} 2950 2951static int (*aurule_callback)(void) = audit_update_lsm_rules; 2952 2953static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid, 2954 u16 class, u32 perms, u32 *retained) 2955{ 2956 int err = 0; 2957 2958 if (event == AVC_CALLBACK_RESET && aurule_callback) 2959 err = aurule_callback(); 2960 return err; 2961} 2962 2963static int __init aurule_init(void) 2964{ 2965 int err; 2966 2967 err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET, 2968 SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0); 2969 if (err) 2970 panic("avc_add_callback() failed, error %d\n", err); 2971 2972 return err; 2973} 2974__initcall(aurule_init); 2975 2976#ifdef CONFIG_NETLABEL 2977/** 2978 * security_netlbl_cache_add - Add an entry to the NetLabel cache 2979 * @secattr: the NetLabel packet security attributes 2980 * @sid: the SELinux SID 2981 * 2982 * Description: 2983 * Attempt to cache the context in @ctx, which was derived from the packet in 2984 * @skb, in the NetLabel subsystem cache. This function assumes @secattr has 2985 * already been initialized. 2986 * 2987 */ 2988static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, 2989 u32 sid) 2990{ 2991 u32 *sid_cache; 2992 2993 sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); 2994 if (sid_cache == NULL) 2995 return; 2996 secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); 2997 if (secattr->cache == NULL) { 2998 kfree(sid_cache); 2999 return; 3000 } 3001 3002 *sid_cache = sid; 3003 secattr->cache->free = kfree; 3004 secattr->cache->data = sid_cache; 3005 secattr->flags |= NETLBL_SECATTR_CACHE; 3006} 3007 3008/** 3009 * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID 3010 * @secattr: the NetLabel packet security attributes 3011 * @sid: the SELinux SID 3012 * 3013 * Description: 3014 * Convert the given NetLabel security attributes in @secattr into a 3015 * SELinux SID. If the @secattr field does not contain a full SELinux 3016 * SID/context then use SECINITSID_NETMSG as the foundation. If possibile the 3017 * 'cache' field of @secattr is set and the CACHE flag is set; this is to 3018 * allow the @secattr to be used by NetLabel to cache the secattr to SID 3019 * conversion for future lookups. Returns zero on success, negative values on 3020 * failure. 3021 * 3022 */ 3023int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, 3024 u32 *sid) 3025{ 3026 int rc = -EIDRM; 3027 struct context *ctx; 3028 struct context ctx_new; 3029 3030 if (!ss_initialized) { 3031 *sid = SECSID_NULL; 3032 return 0; 3033 } 3034 3035 read_lock(&policy_rwlock); 3036 3037 if (secattr->flags & NETLBL_SECATTR_CACHE) { 3038 *sid = *(u32 *)secattr->cache->data; 3039 rc = 0; 3040 } else if (secattr->flags & NETLBL_SECATTR_SECID) { 3041 *sid = secattr->attr.secid; 3042 rc = 0; 3043 } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { 3044 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG); 3045 if (ctx == NULL) 3046 goto netlbl_secattr_to_sid_return; 3047 3048 context_init(&ctx_new); 3049 ctx_new.user = ctx->user; 3050 ctx_new.role = ctx->role; 3051 ctx_new.type = ctx->type; 3052 mls_import_netlbl_lvl(&ctx_new, secattr); 3053 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { 3054 if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat, 3055 secattr->attr.mls.cat) != 0) 3056 goto netlbl_secattr_to_sid_return; 3057 memcpy(&ctx_new.range.level[1].cat, 3058 &ctx_new.range.level[0].cat, 3059 sizeof(ctx_new.range.level[0].cat)); 3060 } 3061 if (mls_context_isvalid(&policydb, &ctx_new) != 1) 3062 goto netlbl_secattr_to_sid_return_cleanup; 3063 3064 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); 3065 if (rc != 0) 3066 goto netlbl_secattr_to_sid_return_cleanup; 3067 3068 security_netlbl_cache_add(secattr, *sid); 3069 3070 ebitmap_destroy(&ctx_new.range.level[0].cat); 3071 } else { 3072 *sid = SECSID_NULL; 3073 rc = 0; 3074 } 3075 3076netlbl_secattr_to_sid_return: 3077 read_unlock(&policy_rwlock); 3078 return rc; 3079netlbl_secattr_to_sid_return_cleanup: 3080 ebitmap_destroy(&ctx_new.range.level[0].cat); 3081 goto netlbl_secattr_to_sid_return; 3082} 3083 3084/** 3085 * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr 3086 * @sid: the SELinux SID 3087 * @secattr: the NetLabel packet security attributes 3088 * 3089 * Description: 3090 * Convert the given SELinux SID in @sid into a NetLabel security attribute. 3091 * Returns zero on success, negative values on failure. 3092 * 3093 */ 3094int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr) 3095{ 3096 int rc; 3097 struct context *ctx; 3098 3099 if (!ss_initialized) 3100 return 0; 3101 3102 read_lock(&policy_rwlock); 3103 ctx = sidtab_search(&sidtab, sid); 3104 if (ctx == NULL) { 3105 rc = -ENOENT; 3106 goto netlbl_sid_to_secattr_failure; 3107 } 3108 secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1], 3109 GFP_ATOMIC); 3110 if (secattr->domain == NULL) { 3111 rc = -ENOMEM; 3112 goto netlbl_sid_to_secattr_failure; 3113 } 3114 secattr->attr.secid = sid; 3115 secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; 3116 mls_export_netlbl_lvl(ctx, secattr); 3117 rc = mls_export_netlbl_cat(ctx, secattr); 3118 if (rc != 0) 3119 goto netlbl_sid_to_secattr_failure; 3120 read_unlock(&policy_rwlock); 3121 3122 return 0; 3123 3124netlbl_sid_to_secattr_failure: 3125 read_unlock(&policy_rwlock); 3126 return rc; 3127} 3128#endif /* CONFIG_NETLABEL */ 3129