security/selinux/ss/services.c

   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  * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
  26  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
  27  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
  28  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
  29  *      This program is free software; you can redistribute it and/or modify
  30  *      it under the terms of the GNU General Public License as published by
  31  *      the Free Software Foundation, version 2.
  32  */
  33 #include <linux/kernel.h>
  34 #include <linux/slab.h>
  35 #include <linux/string.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/rcupdate.h>
  38 #include <linux/errno.h>
  39 #include <linux/in.h>
  40 #include <linux/sched.h>
  41 #include <linux/audit.h>
  42 #include <linux/mutex.h>
  43 #include <linux/selinux.h>
  44 #include <net/netlabel.h>
  45
  46 #include "flask.h"
  47 #include "avc.h"
  48 #include "avc_ss.h"
  49 #include "security.h"
  50 #include "context.h"
  51 #include "policydb.h"
  52 #include "sidtab.h"
  53 #include "services.h"
  54 #include "conditional.h"
  55 #include "mls.h"
  56 #include "objsec.h"
  57 #include "netlabel.h"
  58 #include "xfrm.h"
  59 #include "ebitmap.h"
  60 #include "audit.h"
  61
  62 extern void selnl_notify_policyload(u32 seqno);
  63 unsigned int policydb_loaded_version;
  64
  65 int selinux_policycap_netpeer;
  66 int selinux_policycap_openperm;
  67
  68 /*
  69  * This is declared in avc.c
  70  */
  71 extern const struct selinux_class_perm selinux_class_perm;
  72
  73 static DEFINE_RWLOCK(policy_rwlock);
  74 static DEFINE_MUTEX(load_mutex);
  75
  76 static struct sidtab sidtab;
  77 struct policydb policydb;
  78 int ss_initialized;
  79
  80 /*
  81  * The largest sequence number that has been used when
  82  * providing an access decision to the access vector cache.
  83  * The sequence number only changes when a policy change
  84  * occurs.
  85  */
  86 static u32 latest_granting;
  87
  88 /* Forward declaration. */
  89 static int context_struct_to_string(struct context *context, char **scontext,
  90                                     u32 *scontext_len);
  91
  92 /*
  93  * Return the boolean value of a constraint expression
  94  * when it is applied to the specified source and target
  95  * security contexts.
  96  *
  97  * xcontext is a special beast...  It is used by the validatetrans rules
  98  * only.  For these rules, scontext is the context before the transition,
  99  * tcontext is the context after the transition, and xcontext is the context
 100  * of the process performing the transition.  All other callers of
 101  * constraint_expr_eval should pass in NULL for xcontext.
 102  */
 103 static int constraint_expr_eval(struct context *scontext,
 104                                 struct context *tcontext,
 105                                 struct context *xcontext,
 106                                 struct constraint_expr *cexpr)
 107 {
 108         u32 val1, val2;
 109         struct context *c;
 110         struct role_datum *r1, *r2;
 111         struct mls_level *l1, *l2;
 112         struct constraint_expr *e;
 113         int s[CEXPR_MAXDEPTH];
 114         int sp = -1;
 115
 116         for (e = cexpr; e; e = e->next) {
 117                 switch (e->expr_type) {
 118                 case CEXPR_NOT:
 119                         BUG_ON(sp < 0);
 120                         s[sp] = !s[sp];
 121                         break;
 122                 case CEXPR_AND:
 123                         BUG_ON(sp < 1);
 124                         sp--;
 125                         s[sp] &= s[sp+1];
 126                         break;
 127                 case CEXPR_OR:
 128                         BUG_ON(sp < 1);
 129                         sp--;
 130                         s[sp] |= s[sp+1];
 131                         break;
 132                 case CEXPR_ATTR:
 133                         if (sp == (CEXPR_MAXDEPTH-1))
 134                                 return 0;
 135                         switch (e->attr) {
 136                         case CEXPR_USER:
 137                                 val1 = scontext->user;
 138                                 val2 = tcontext->user;
 139                                 break;
 140                         case CEXPR_TYPE:
 141                                 val1 = scontext->type;
 142                                 val2 = tcontext->type;
 143                                 break;
 144                         case CEXPR_ROLE:
 145                                 val1 = scontext->role;
 146                                 val2 = tcontext->role;
 147                                 r1 = policydb.role_val_to_struct[val1 - 1];
 148                                 r2 = policydb.role_val_to_struct[val2 - 1];
 149                                 switch (e->op) {
 150                                 case CEXPR_DOM:
 151                                         s[++sp] = ebitmap_get_bit(&r1->dominates,
 152                                                                   val2 - 1);
 153                                         continue;
 154                                 case CEXPR_DOMBY:
 155                                         s[++sp] = ebitmap_get_bit(&r2->dominates,
 156                                                                   val1 - 1);
 157                                         continue;
 158                                 case CEXPR_INCOMP:
 159                                         s[++sp] = (!ebitmap_get_bit(&r1->dominates,
 160                                                                     val2 - 1) &&
 161                                                    !ebitmap_get_bit(&r2->dominates,
 162                                                                     val1 - 1));
 163                                         continue;
 164                                 default:
 165                                         break;
 166                                 }
 167                                 break;
 168                         case CEXPR_L1L2:
 169                                 l1 = &(scontext->range.level[0]);
 170                                 l2 = &(tcontext->range.level[0]);
 171                                 goto mls_ops;
 172                         case CEXPR_L1H2:
 173                                 l1 = &(scontext->range.level[0]);
 174                                 l2 = &(tcontext->range.level[1]);
 175                                 goto mls_ops;
 176                         case CEXPR_H1L2:
 177                                 l1 = &(scontext->range.level[1]);
 178                                 l2 = &(tcontext->range.level[0]);
 179                                 goto mls_ops;
 180                         case CEXPR_H1H2:
 181                                 l1 = &(scontext->range.level[1]);
 182                                 l2 = &(tcontext->range.level[1]);
 183                                 goto mls_ops;
 184                         case CEXPR_L1H1:
 185                                 l1 = &(scontext->range.level[0]);
 186                                 l2 = &(scontext->range.level[1]);
 187                                 goto mls_ops;
 188                         case CEXPR_L2H2:
 189                                 l1 = &(tcontext->range.level[0]);
 190                                 l2 = &(tcontext->range.level[1]);
 191                                 goto mls_ops;
 192 mls_ops:
 193                         switch (e->op) {
 194                         case CEXPR_EQ:
 195                                 s[++sp] = mls_level_eq(l1, l2);
 196                                 continue;
 197                         case CEXPR_NEQ:
 198                                 s[++sp] = !mls_level_eq(l1, l2);
 199                                 continue;
 200                         case CEXPR_DOM:
 201                                 s[++sp] = mls_level_dom(l1, l2);
 202                                 continue;
 203                         case CEXPR_DOMBY:
 204                                 s[++sp] = mls_level_dom(l2, l1);
 205                                 continue;
 206                         case CEXPR_INCOMP:
 207                                 s[++sp] = mls_level_incomp(l2, l1);
 208                                 continue;
 209                         default:
 210                                 BUG();
 211                                 return 0;
 212                         }
 213                         break;
 214                         default:
 215                                 BUG();
 216                                 return 0;
 217                         }
 218
 219                         switch (e->op) {
 220                         case CEXPR_EQ:
 221                                 s[++sp] = (val1 == val2);
 222                                 break;
 223                         case CEXPR_NEQ:
 224                                 s[++sp] = (val1 != val2);
 225                                 break;
 226                         default:
 227                                 BUG();
 228                                 return 0;
 229                         }
 230                         break;
 231                 case CEXPR_NAMES:
 232                         if (sp == (CEXPR_MAXDEPTH-1))
 233                                 return 0;
 234                         c = scontext;
 235                         if (e->attr & CEXPR_TARGET)
 236                                 c = tcontext;
 237                         else if (e->attr & CEXPR_XTARGET) {
 238                                 c = xcontext;
 239                                 if (!c) {
 240                                         BUG();
 241                                         return 0;
 242                                 }
 243                         }
 244                         if (e->attr & CEXPR_USER)
 245                                 val1 = c->user;
 246                         else if (e->attr & CEXPR_ROLE)
 247                                 val1 = c->role;
 248                         else if (e->attr & CEXPR_TYPE)
 249                                 val1 = c->type;
 250                         else {
 251                                 BUG();
 252                                 return 0;
 253                         }
 254
 255                         switch (e->op) {
 256                         case CEXPR_EQ:
 257                                 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
 258                                 break;
 259                         case CEXPR_NEQ:
 260                                 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
 261                                 break;
 262                         default:
 263                                 BUG();
 264                                 return 0;
 265                         }
 266                         break;
 267                 default:
 268                         BUG();
 269                         return 0;
 270                 }
 271         }
 272
 273         BUG_ON(sp != 0);
 274         return s[0];
 275 }
 276
 277 /*
 278  * Compute access vectors based on a context structure pair for
 279  * the permissions in a particular class.
 280  */
 281 static int context_struct_compute_av(struct context *scontext,
 282                                      struct context *tcontext,
 283                                      u16 tclass,
 284                                      u32 requested,
 285                                      struct av_decision *avd)
 286 {
 287         struct constraint_node *constraint;
 288         struct role_allow *ra;
 289         struct avtab_key avkey;
 290         struct avtab_node *node;
 291         struct class_datum *tclass_datum;
 292         struct ebitmap *sattr, *tattr;
 293         struct ebitmap_node *snode, *tnode;
 294         const struct selinux_class_perm *kdefs = &selinux_class_perm;
 295         unsigned int i, j;
 296
 297         /*
 298          * Remap extended Netlink classes for old policy versions.
 299          * Do this here rather than socket_type_to_security_class()
 300          * in case a newer policy version is loaded, allowing sockets
 301          * to remain in the correct class.
 302          */
 303         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 304                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 305                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 306                         tclass = SECCLASS_NETLINK_SOCKET;
 307
 308         /*
 309          * Initialize the access vectors to the default values.
 310          */
 311         avd->allowed = 0;
 312         avd->decided = 0xffffffff;
 313         avd->auditallow = 0;
 314         avd->auditdeny = 0xffffffff;
 315         avd->seqno = latest_granting;
 316
 317         /*
 318          * Check for all the invalid cases.
 319          * - tclass 0
 320          * - tclass > policy and > kernel
 321          * - tclass > policy but is a userspace class
 322          * - tclass > policy but we do not allow unknowns
 323          */
 324         if (unlikely(!tclass))
 325                 goto inval_class;
 326         if (unlikely(tclass > policydb.p_classes.nprim))
 327                 if (tclass > kdefs->cts_len ||
 328                     !kdefs->class_to_string[tclass] ||
 329                     !policydb.allow_unknown)
 330                         goto inval_class;
 331
 332         /*
 333          * Kernel class and we allow unknown so pad the allow decision
 334          * the pad will be all 1 for unknown classes.
 335          */
 336         if (tclass <= kdefs->cts_len && policydb.allow_unknown)
 337                 avd->allowed = policydb.undefined_perms[tclass - 1];
 338
 339         /*
 340          * Not in policy. Since decision is completed (all 1 or all 0) return.
 341          */
 342         if (unlikely(tclass > policydb.p_classes.nprim))
 343                 return 0;
 344
 345         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 346
 347         /*
 348          * If a specific type enforcement rule was defined for
 349          * this permission check, then use it.
 350          */
 351         avkey.target_class = tclass;
 352         avkey.specified = AVTAB_AV;
 353         sattr = &policydb.type_attr_map[scontext->type - 1];
 354         tattr = &policydb.type_attr_map[tcontext->type - 1];
 355         ebitmap_for_each_positive_bit(sattr, snode, i) {
 356                 ebitmap_for_each_positive_bit(tattr, tnode, j) {
 357                         avkey.source_type = i + 1;
 358                         avkey.target_type = j + 1;
 359                         for (node = avtab_search_node(&policydb.te_avtab, &avkey);
 360                              node != NULL;
 361                              node = avtab_search_node_next(node, avkey.specified)) {
 362                                 if (node->key.specified == AVTAB_ALLOWED)
 363                                         avd->allowed |= node->datum.data;
 364                                 else if (node->key.specified == AVTAB_AUDITALLOW)
 365                                         avd->auditallow |= node->datum.data;
 366                                 else if (node->key.specified == AVTAB_AUDITDENY)
 367                                         avd->auditdeny &= node->datum.data;
 368                         }
 369
 370                         /* Check conditional av table for additional permissions */
 371                         cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
 372
 373                 }
 374         }
 375
 376         /*
 377          * Remove any permissions prohibited by a constraint (this includes
 378          * the MLS policy).
 379          */
 380         constraint = tclass_datum->constraints;
 381         while (constraint) {
 382                 if ((constraint->permissions & (avd->allowed)) &&
 383                     !constraint_expr_eval(scontext, tcontext, NULL,
 384                                           constraint->expr)) {
 385                         avd->allowed = (avd->allowed) & ~(constraint->permissions);
 386                 }
 387                 constraint = constraint->next;
 388         }
 389
 390         /*
 391          * If checking process transition permission and the
 392          * role is changing, then check the (current_role, new_role)
 393          * pair.
 394          */
 395         if (tclass == SECCLASS_PROCESS &&
 396             (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
 397             scontext->role != tcontext->role) {
 398                 for (ra = policydb.role_allow; ra; ra = ra->next) {
 399                         if (scontext->role == ra->role &&
 400                             tcontext->role == ra->new_role)
 401                                 break;
 402                 }
 403                 if (!ra)
 404                         avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
 405                                                         PROCESS__DYNTRANSITION);
 406         }
 407
 408         return 0;
 409
 410 inval_class:
 411         printk(KERN_ERR "SELinux: %s:  unrecognized class %d\n", __func__,
 412                 tclass);
 413         return -EINVAL;
 414 }
 415
 416 /*
 417  * Given a sid find if the type has the permissive flag set
 418  */
 419 int security_permissive_sid(u32 sid)
 420 {
 421         struct context *context;
 422         u32 type;
 423         int rc;
 424
 425         read_lock(&policy_rwlock);
 426
 427         context = sidtab_search(&sidtab, sid);
 428         BUG_ON(!context);
 429
 430         type = context->type;
 431         /*
 432          * we are intentionally using type here, not type-1, the 0th bit may
 433          * someday indicate that we are globally setting permissive in policy.
 434          */
 435         rc = ebitmap_get_bit(&policydb.permissive_map, type);
 436
 437         read_unlock(&policy_rwlock);
 438         return rc;
 439 }
 440
 441 static int security_validtrans_handle_fail(struct context *ocontext,
 442                                            struct context *ncontext,
 443                                            struct context *tcontext,
 444                                            u16 tclass)
 445 {
 446         char *o = NULL, *n = NULL, *t = NULL;
 447         u32 olen, nlen, tlen;
 448
 449         if (context_struct_to_string(ocontext, &o, &olen) < 0)
 450                 goto out;
 451         if (context_struct_to_string(ncontext, &n, &nlen) < 0)
 452                 goto out;
 453         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 454                 goto out;
 455         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 456                   "security_validate_transition:  denied for"
 457                   " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
 458                   o, n, t, policydb.p_class_val_to_name[tclass-1]);
 459 out:
 460         kfree(o);
 461         kfree(n);
 462         kfree(t);
 463
 464         if (!selinux_enforcing)
 465                 return 0;
 466         return -EPERM;
 467 }
 468
 469 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
 470                                  u16 tclass)
 471 {
 472         struct context *ocontext;
 473         struct context *ncontext;
 474         struct context *tcontext;
 475         struct class_datum *tclass_datum;
 476         struct constraint_node *constraint;
 477         int rc = 0;
 478
 479         if (!ss_initialized)
 480                 return 0;
 481
 482         read_lock(&policy_rwlock);
 483
 484         /*
 485          * Remap extended Netlink classes for old policy versions.
 486          * Do this here rather than socket_type_to_security_class()
 487          * in case a newer policy version is loaded, allowing sockets
 488          * to remain in the correct class.
 489          */
 490         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 491                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 492                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 493                         tclass = SECCLASS_NETLINK_SOCKET;
 494
 495         if (!tclass || tclass > policydb.p_classes.nprim) {
 496                 printk(KERN_ERR "SELinux: %s:  unrecognized class %d\n",
 497                         __func__, tclass);
 498                 rc = -EINVAL;
 499                 goto out;
 500         }
 501         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 502
 503         ocontext = sidtab_search(&sidtab, oldsid);
 504         if (!ocontext) {
 505                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 506                         __func__, oldsid);
 507                 rc = -EINVAL;
 508                 goto out;
 509         }
 510
 511         ncontext = sidtab_search(&sidtab, newsid);
 512         if (!ncontext) {
 513                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 514                         __func__, newsid);
 515                 rc = -EINVAL;
 516                 goto out;
 517         }
 518
 519         tcontext = sidtab_search(&sidtab, tasksid);
 520         if (!tcontext) {
 521                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 522                         __func__, tasksid);
 523                 rc = -EINVAL;
 524                 goto out;
 525         }
 526
 527         constraint = tclass_datum->validatetrans;
 528         while (constraint) {
 529                 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
 530                                           constraint->expr)) {
 531                         rc = security_validtrans_handle_fail(ocontext, ncontext,
 532                                                              tcontext, tclass);
 533                         goto out;
 534                 }
 535                 constraint = constraint->next;
 536         }
 537
 538 out:
 539         read_unlock(&policy_rwlock);
 540         return rc;
 541 }
 542
 543 /**
 544  * security_compute_av - Compute access vector decisions.
 545  * @ssid: source security identifier
 546  * @tsid: target security identifier
 547  * @tclass: target security class
 548  * @requested: requested permissions
 549  * @avd: access vector decisions
 550  *
 551  * Compute a set of access vector decisions based on the
 552  * SID pair (@ssid, @tsid) for the permissions in @tclass.
 553  * Return -%EINVAL if any of the parameters are invalid or %0
 554  * if the access vector decisions were computed successfully.
 555  */
 556 int security_compute_av(u32 ssid,
 557                         u32 tsid,
 558                         u16 tclass,
 559                         u32 requested,
 560                         struct av_decision *avd)
 561 {
 562         struct context *scontext = NULL, *tcontext = NULL;
 563         int rc = 0;
 564
 565         if (!ss_initialized) {
 566                 avd->allowed = 0xffffffff;
 567                 avd->decided = 0xffffffff;
 568                 avd->auditallow = 0;
 569                 avd->auditdeny = 0xffffffff;
 570                 avd->seqno = latest_granting;
 571                 return 0;
 572         }
 573
 574         read_lock(&policy_rwlock);
 575
 576         scontext = sidtab_search(&sidtab, ssid);
 577         if (!scontext) {
 578                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 579                        __func__, ssid);
 580                 rc = -EINVAL;
 581                 goto out;
 582         }
 583         tcontext = sidtab_search(&sidtab, tsid);
 584         if (!tcontext) {
 585                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 586                        __func__, tsid);
 587                 rc = -EINVAL;
 588                 goto out;
 589         }
 590
 591         rc = context_struct_compute_av(scontext, tcontext, tclass,
 592                                        requested, avd);
 593 out:
 594         read_unlock(&policy_rwlock);
 595         return rc;
 596 }
 597
 598 /*
 599  * Write the security context string representation of
 600  * the context structure `context' into a dynamically
 601  * allocated string of the correct size.  Set `*scontext'
 602  * to point to this string and set `*scontext_len' to
 603  * the length of the string.
 604  */
 605 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
 606 {
 607         char *scontextp;
 608
 609         *scontext = NULL;
 610         *scontext_len = 0;
 611
 612         if (context->len) {
 613                 *scontext_len = context->len;
 614                 *scontext = kstrdup(context->str, GFP_ATOMIC);
 615                 if (!(*scontext))
 616                         return -ENOMEM;
 617                 return 0;
 618         }
 619
 620         /* Compute the size of the context. */
 621         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
 622         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
 623         *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
 624         *scontext_len += mls_compute_context_len(context);
 625
 626         /* Allocate space for the context; caller must free this space. */
 627         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 628         if (!scontextp)
 629                 return -ENOMEM;
 630         *scontext = scontextp;
 631
 632         /*
 633          * Copy the user name, role name and type name into the context.
 634          */
 635         sprintf(scontextp, "%s:%s:%s",
 636                 policydb.p_user_val_to_name[context->user - 1],
 637                 policydb.p_role_val_to_name[context->role - 1],
 638                 policydb.p_type_val_to_name[context->type - 1]);
 639         scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
 640                      1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
 641                      1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
 642
 643         mls_sid_to_context(context, &scontextp);
 644
 645         *scontextp = 0;
 646
 647         return 0;
 648 }
 649
 650 #include "initial_sid_to_string.h"
 651
 652 const char *security_get_initial_sid_context(u32 sid)
 653 {
 654         if (unlikely(sid > SECINITSID_NUM))
 655                 return NULL;
 656         return initial_sid_to_string[sid];
 657 }
 658
 659 static int security_sid_to_context_core(u32 sid, char **scontext,
 660                                         u32 *scontext_len, int force)
 661 {
 662         struct context *context;
 663         int rc = 0;
 664
 665         *scontext = NULL;
 666         *scontext_len  = 0;
 667
 668         if (!ss_initialized) {
 669                 if (sid <= SECINITSID_NUM) {
 670                         char *scontextp;
 671
 672                         *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
 673                         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 674                         if (!scontextp) {
 675                                 rc = -ENOMEM;
 676                                 goto out;
 677                         }
 678                         strcpy(scontextp, initial_sid_to_string[sid]);
 679                         *scontext = scontextp;
 680                         goto out;
 681                 }
 682                 printk(KERN_ERR "SELinux: %s:  called before initial "
 683                        "load_policy on unknown SID %d\n", __func__, sid);
 684                 rc = -EINVAL;
 685                 goto out;
 686         }
 687         read_lock(&policy_rwlock);
 688         if (force)
 689                 context = sidtab_search_force(&sidtab, sid);
 690         else
 691                 context = sidtab_search(&sidtab, sid);
 692         if (!context) {
 693                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 694                         __func__, sid);
 695                 rc = -EINVAL;
 696                 goto out_unlock;
 697         }
 698         rc = context_struct_to_string(context, scontext, scontext_len);
 699 out_unlock:
 700         read_unlock(&policy_rwlock);
 701 out:
 702         return rc;
 703
 704 }
 705
 706 /**
 707  * security_sid_to_context - Obtain a context for a given SID.
 708  * @sid: security identifier, SID
 709  * @scontext: security context
 710  * @scontext_len: length in bytes
 711  *
 712  * Write the string representation of the context associated with @sid
 713  * into a dynamically allocated string of the correct size.  Set @scontext
 714  * to point to this string and set @scontext_len to the length of the string.
 715  */
 716 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
 717 {
 718         return security_sid_to_context_core(sid, scontext, scontext_len, 0);
 719 }
 720
 721 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
 722 {
 723         return security_sid_to_context_core(sid, scontext, scontext_len, 1);
 724 }
 725
 726 /*
 727  * Caveat:  Mutates scontext.
 728  */
 729 static int string_to_context_struct(struct policydb *pol,
 730                                     struct sidtab *sidtabp,
 731                                     char *scontext,
 732                                     u32 scontext_len,
 733                                     struct context *ctx,
 734                                     u32 def_sid)
 735 {
 736         struct role_datum *role;
 737         struct type_datum *typdatum;
 738         struct user_datum *usrdatum;
 739         char *scontextp, *p, oldc;
 740         int rc = 0;
 741
 742         context_init(ctx);
 743
 744         /* Parse the security context. */
 745
 746         rc = -EINVAL;
 747         scontextp = (char *) scontext;
 748
 749         /* Extract the user. */
 750         p = scontextp;
 751         while (*p && *p != ':')
 752                 p++;
 753
 754         if (*p == 0)
 755                 goto out;
 756
 757         *p++ = 0;
 758
 759         usrdatum = hashtab_search(pol->p_users.table, scontextp);
 760         if (!usrdatum)
 761                 goto out;
 762
 763         ctx->user = usrdatum->value;
 764
 765         /* Extract role. */
 766         scontextp = p;
 767         while (*p && *p != ':')
 768                 p++;
 769
 770         if (*p == 0)
 771                 goto out;
 772
 773         *p++ = 0;
 774
 775         role = hashtab_search(pol->p_roles.table, scontextp);
 776         if (!role)
 777                 goto out;
 778         ctx->role = role->value;
 779
 780         /* Extract type. */
 781         scontextp = p;
 782         while (*p && *p != ':')
 783                 p++;
 784         oldc = *p;
 785         *p++ = 0;
 786
 787         typdatum = hashtab_search(pol->p_types.table, scontextp);
 788         if (!typdatum)
 789                 goto out;
 790
 791         ctx->type = typdatum->value;
 792
 793         rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
 794         if (rc)
 795                 goto out;
 796
 797         if ((p - scontext) < scontext_len) {
 798                 rc = -EINVAL;
 799                 goto out;
 800         }
 801
 802         /* Check the validity of the new context. */
 803         if (!policydb_context_isvalid(pol, ctx)) {
 804                 rc = -EINVAL;
 805                 context_destroy(ctx);
 806                 goto out;
 807         }
 808         rc = 0;
 809 out:
 810         return rc;
 811 }
 812
 813 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
 814                                         u32 *sid, u32 def_sid, gfp_t gfp_flags,
 815                                         int force)
 816 {
 817         char *scontext2, *str = NULL;
 818         struct context context;
 819         int rc = 0;
 820
 821         if (!ss_initialized) {
 822                 int i;
 823
 824                 for (i = 1; i < SECINITSID_NUM; i++) {
 825                         if (!strcmp(initial_sid_to_string[i], scontext)) {
 826                                 *sid = i;
 827                                 return 0;
 828                         }
 829                 }
 830                 *sid = SECINITSID_KERNEL;
 831                 return 0;
 832         }
 833         *sid = SECSID_NULL;
 834
 835         /* Copy the string so that we can modify the copy as we parse it. */
 836         scontext2 = kmalloc(scontext_len+1, gfp_flags);
 837         if (!scontext2)
 838                 return -ENOMEM;
 839         memcpy(scontext2, scontext, scontext_len);
 840         scontext2[scontext_len] = 0;
 841
 842         if (force) {
 843                 /* Save another copy for storing in uninterpreted form */
 844                 str = kstrdup(scontext2, gfp_flags);
 845                 if (!str) {
 846                         kfree(scontext2);
 847                         return -ENOMEM;
 848                 }
 849         }
 850
 851         read_lock(&policy_rwlock);
 852         rc = string_to_context_struct(&policydb, &sidtab,
 853                                       scontext2, scontext_len,
 854                                       &context, def_sid);
 855         if (rc == -EINVAL && force) {
 856                 context.str = str;
 857                 context.len = scontext_len;
 858                 str = NULL;
 859         } else if (rc)
 860                 goto out;
 861         rc = sidtab_context_to_sid(&sidtab, &context, sid);
 862         if (rc)
 863                 context_destroy(&context);
 864 out:
 865         read_unlock(&policy_rwlock);
 866         kfree(scontext2);
 867         kfree(str);
 868         return rc;
 869 }
 870
 871 /**
 872  * security_context_to_sid - Obtain a SID for a given security context.
 873  * @scontext: security context
 874  * @scontext_len: length in bytes
 875  * @sid: security identifier, SID
 876  *
 877  * Obtains a SID associated with the security context that
 878  * has the string representation specified by @scontext.
 879  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 880  * memory is available, or 0 on success.
 881  */
 882 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
 883 {
 884         return security_context_to_sid_core(scontext, scontext_len,
 885                                             sid, SECSID_NULL, GFP_KERNEL, 0);
 886 }
 887
 888 /**
 889  * security_context_to_sid_default - Obtain a SID for a given security context,
 890  * falling back to specified default if needed.
 891  *
 892  * @scontext: security context
 893  * @scontext_len: length in bytes
 894  * @sid: security identifier, SID
 895  * @def_sid: default SID to assign on error
 896  *
 897  * Obtains a SID associated with the security context that
 898  * has the string representation specified by @scontext.
 899  * The default SID is passed to the MLS layer to be used to allow
 900  * kernel labeling of the MLS field if the MLS field is not present
 901  * (for upgrading to MLS without full relabel).
 902  * Implicitly forces adding of the context even if it cannot be mapped yet.
 903  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 904  * memory is available, or 0 on success.
 905  */
 906 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
 907                                     u32 *sid, u32 def_sid, gfp_t gfp_flags)
 908 {
 909         return security_context_to_sid_core(scontext, scontext_len,
 910                                             sid, def_sid, gfp_flags, 1);
 911 }
 912
 913 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
 914                                   u32 *sid)
 915 {
 916         return security_context_to_sid_core(scontext, scontext_len,
 917                                             sid, SECSID_NULL, GFP_KERNEL, 1);
 918 }
 919
 920 static int compute_sid_handle_invalid_context(
 921         struct context *scontext,
 922         struct context *tcontext,
 923         u16 tclass,
 924         struct context *newcontext)
 925 {
 926         char *s = NULL, *t = NULL, *n = NULL;
 927         u32 slen, tlen, nlen;
 928
 929         if (context_struct_to_string(scontext, &s, &slen) < 0)
 930                 goto out;
 931         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 932                 goto out;
 933         if (context_struct_to_string(newcontext, &n, &nlen) < 0)
 934                 goto out;
 935         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 936                   "security_compute_sid:  invalid context %s"
 937                   " for scontext=%s"
 938                   " tcontext=%s"
 939                   " tclass=%s",
 940                   n, s, t, policydb.p_class_val_to_name[tclass-1]);
 941 out:
 942         kfree(s);
 943         kfree(t);
 944         kfree(n);
 945         if (!selinux_enforcing)
 946                 return 0;
 947         return -EACCES;
 948 }
 949
 950 static int security_compute_sid(u32 ssid,
 951                                 u32 tsid,
 952                                 u16 tclass,
 953                                 u32 specified,
 954                                 u32 *out_sid)
 955 {
 956         struct context *scontext = NULL, *tcontext = NULL, newcontext;
 957         struct role_trans *roletr = NULL;
 958         struct avtab_key avkey;
 959         struct avtab_datum *avdatum;
 960         struct avtab_node *node;
 961         int rc = 0;
 962
 963         if (!ss_initialized) {
 964                 switch (tclass) {
 965                 case SECCLASS_PROCESS:
 966                         *out_sid = ssid;
 967                         break;
 968                 default:
 969                         *out_sid = tsid;
 970                         break;
 971                 }
 972                 goto out;
 973         }
 974
 975         context_init(&newcontext);
 976
 977         read_lock(&policy_rwlock);
 978
 979         scontext = sidtab_search(&sidtab, ssid);
 980         if (!scontext) {
 981                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 982                        __func__, ssid);
 983                 rc = -EINVAL;
 984                 goto out_unlock;
 985         }
 986         tcontext = sidtab_search(&sidtab, tsid);
 987         if (!tcontext) {
 988                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 989                        __func__, tsid);
 990                 rc = -EINVAL;
 991                 goto out_unlock;
 992         }
 993
 994         /* Set the user identity. */
 995         switch (specified) {
 996         case AVTAB_TRANSITION:
 997         case AVTAB_CHANGE:
 998                 /* Use the process user identity. */
 999                 newcontext.user = scontext->user;
1000                 break;
1001         case AVTAB_MEMBER:
1002                 /* Use the related object owner. */
1003                 newcontext.user = tcontext->user;
1004                 break;
1005         }
1006
1007         /* Set the role and type to default values. */
1008         switch (tclass) {
1009         case SECCLASS_PROCESS:
1010                 /* Use the current role and type of process. */
1011                 newcontext.role = scontext->role;
1012                 newcontext.type = scontext->type;
1013                 break;
1014         default:
1015                 /* Use the well-defined object role. */
1016                 newcontext.role = OBJECT_R_VAL;
1017                 /* Use the type of the related object. */
1018                 newcontext.type = tcontext->type;
1019         }
1020
1021         /* Look for a type transition/member/change rule. */
1022         avkey.source_type = scontext->type;
1023         avkey.target_type = tcontext->type;
1024         avkey.target_class = tclass;
1025         avkey.specified = specified;
1026         avdatum = avtab_search(&policydb.te_avtab, &avkey);
1027
1028         /* If no permanent rule, also check for enabled conditional rules */
1029         if (!avdatum) {
1030                 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1031                 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
1032                         if (node->key.specified & AVTAB_ENABLED) {
1033                                 avdatum = &node->datum;
1034                                 break;
1035                         }
1036                 }
1037         }
1038
1039         if (avdatum) {
1040                 /* Use the type from the type transition/member/change rule. */
1041                 newcontext.type = avdatum->data;
1042         }
1043
1044         /* Check for class-specific changes. */
1045         switch (tclass) {
1046         case SECCLASS_PROCESS:
1047                 if (specified & AVTAB_TRANSITION) {
1048                         /* Look for a role transition rule. */
1049                         for (roletr = policydb.role_tr; roletr;
1050                              roletr = roletr->next) {
1051                                 if (roletr->role == scontext->role &&
1052                                     roletr->type == tcontext->type) {
1053                                         /* Use the role transition rule. */
1054                                         newcontext.role = roletr->new_role;
1055                                         break;
1056                                 }
1057                         }
1058                 }
1059                 break;
1060         default:
1061                 break;
1062         }
1063
1064         /* Set the MLS attributes.
1065            This is done last because it may allocate memory. */
1066         rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
1067         if (rc)
1068                 goto out_unlock;
1069
1070         /* Check the validity of the context. */
1071         if (!policydb_context_isvalid(&policydb, &newcontext)) {
1072                 rc = compute_sid_handle_invalid_context(scontext,
1073                                                         tcontext,
1074                                                         tclass,
1075                                                         &newcontext);
1076                 if (rc)
1077                         goto out_unlock;
1078         }
1079         /* Obtain the sid for the context. */
1080         rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1081 out_unlock:
1082         read_unlock(&policy_rwlock);
1083         context_destroy(&newcontext);
1084 out:
1085         return rc;
1086 }
1087
1088 /**
1089  * security_transition_sid - Compute the SID for a new subject/object.
1090  * @ssid: source security identifier
1091  * @tsid: target security identifier
1092  * @tclass: target security class
1093  * @out_sid: security identifier for new subject/object
1094  *
1095  * Compute a SID to use for labeling a new subject or object in the
1096  * class @tclass based on a SID pair (@ssid, @tsid).
1097  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1098  * if insufficient memory is available, or %0 if the new SID was
1099  * computed successfully.
1100  */
1101 int security_transition_sid(u32 ssid,
1102                             u32 tsid,
1103                             u16 tclass,
1104                             u32 *out_sid)
1105 {
1106         return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
1107 }
1108
1109 /**
1110  * security_member_sid - Compute the SID for member selection.
1111  * @ssid: source security identifier
1112  * @tsid: target security identifier
1113  * @tclass: target security class
1114  * @out_sid: security identifier for selected member
1115  *
1116  * Compute a SID to use when selecting a member of a polyinstantiated
1117  * object of class @tclass based on a SID pair (@ssid, @tsid).
1118  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1119  * if insufficient memory is available, or %0 if the SID was
1120  * computed successfully.
1121  */
1122 int security_member_sid(u32 ssid,
1123                         u32 tsid,
1124                         u16 tclass,
1125                         u32 *out_sid)
1126 {
1127         return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
1128 }
1129
1130 /**
1131  * security_change_sid - Compute the SID for object relabeling.
1132  * @ssid: source security identifier
1133  * @tsid: target security identifier
1134  * @tclass: target security class
1135  * @out_sid: security identifier for selected member
1136  *
1137  * Compute a SID to use for relabeling an object of class @tclass
1138  * based on a SID pair (@ssid, @tsid).
1139  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1140  * if insufficient memory is available, or %0 if the SID was
1141  * computed successfully.
1142  */
1143 int security_change_sid(u32 ssid,
1144                         u32 tsid,
1145                         u16 tclass,
1146                         u32 *out_sid)
1147 {
1148         return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1149 }
1150
1151 /*
1152  * Verify that each kernel class that is defined in the
1153  * policy is correct
1154  */
1155 static int validate_classes(struct policydb *p)
1156 {
1157         int i, j;
1158         struct class_datum *cladatum;
1159         struct perm_datum *perdatum;
1160         u32 nprim, tmp, common_pts_len, perm_val, pol_val;
1161         u16 class_val;
1162         const struct selinux_class_perm *kdefs = &selinux_class_perm;
1163         const char *def_class, *def_perm, *pol_class;
1164         struct symtab *perms;
1165
1166         if (p->allow_unknown) {
1167                 u32 num_classes = kdefs->cts_len;
1168                 p->undefined_perms = kcalloc(num_classes, sizeof(u32), GFP_KERNEL);
1169                 if (!p->undefined_perms)
1170                         return -ENOMEM;
1171         }
1172
1173         for (i = 1; i < kdefs->cts_len; i++) {
1174                 def_class = kdefs->class_to_string[i];
1175                 if (!def_class)
1176                         continue;
1177                 if (i > p->p_classes.nprim) {
1178                         printk(KERN_INFO
1179                                "SELinux:  class %s not defined in policy\n",
1180                                def_class);
1181                         if (p->reject_unknown)
1182                                 return -EINVAL;
1183                         if (p->allow_unknown)
1184                                 p->undefined_perms[i-1] = ~0U;
1185                         continue;
1186                 }
1187                 pol_class = p->p_class_val_to_name[i-1];
1188                 if (strcmp(pol_class, def_class)) {
1189                         printk(KERN_ERR
1190                                "SELinux:  class %d is incorrect, found %s but should be %s\n",
1191                                i, pol_class, def_class);
1192                         return -EINVAL;
1193                 }
1194         }
1195         for (i = 0; i < kdefs->av_pts_len; i++) {
1196                 class_val = kdefs->av_perm_to_string[i].tclass;
1197                 perm_val = kdefs->av_perm_to_string[i].value;
1198                 def_perm = kdefs->av_perm_to_string[i].name;
1199                 if (class_val > p->p_classes.nprim)
1200                         continue;
1201                 pol_class = p->p_class_val_to_name[class_val-1];
1202                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1203                 BUG_ON(!cladatum);
1204                 perms = &cladatum->permissions;
1205                 nprim = 1 << (perms->nprim - 1);
1206                 if (perm_val > nprim) {
1207                         printk(KERN_INFO
1208                                "SELinux:  permission %s in class %s not defined in policy\n",
1209                                def_perm, pol_class);
1210                         if (p->reject_unknown)
1211                                 return -EINVAL;
1212                         if (p->allow_unknown)
1213                                 p->undefined_perms[class_val-1] |= perm_val;
1214                         continue;
1215                 }
1216                 perdatum = hashtab_search(perms->table, def_perm);
1217                 if (perdatum == NULL) {
1218                         printk(KERN_ERR
1219                                "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1220                                def_perm, pol_class);
1221                         return -EINVAL;
1222                 }
1223                 pol_val = 1 << (perdatum->value - 1);
1224                 if (pol_val != perm_val) {
1225                         printk(KERN_ERR
1226                                "SELinux:  permission %s in class %s has incorrect value\n",
1227                                def_perm, pol_class);
1228                         return -EINVAL;
1229                 }
1230         }
1231         for (i = 0; i < kdefs->av_inherit_len; i++) {
1232                 class_val = kdefs->av_inherit[i].tclass;
1233                 if (class_val > p->p_classes.nprim)
1234                         continue;
1235                 pol_class = p->p_class_val_to_name[class_val-1];
1236                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1237                 BUG_ON(!cladatum);
1238                 if (!cladatum->comdatum) {
1239                         printk(KERN_ERR
1240                                "SELinux:  class %s should have an inherits clause but does not\n",
1241                                pol_class);
1242                         return -EINVAL;
1243                 }
1244                 tmp = kdefs->av_inherit[i].common_base;
1245                 common_pts_len = 0;
1246                 while (!(tmp & 0x01)) {
1247                         common_pts_len++;
1248                         tmp >>= 1;
1249                 }
1250                 perms = &cladatum->comdatum->permissions;
1251                 for (j = 0; j < common_pts_len; j++) {
1252                         def_perm = kdefs->av_inherit[i].common_pts[j];
1253                         if (j >= perms->nprim) {
1254                                 printk(KERN_INFO
1255                                        "SELinux:  permission %s in class %s not defined in policy\n",
1256                                        def_perm, pol_class);
1257                                 if (p->reject_unknown)
1258                                         return -EINVAL;
1259                                 if (p->allow_unknown)
1260                                         p->undefined_perms[class_val-1] |= (1 << j);
1261                                 continue;
1262                         }
1263                         perdatum = hashtab_search(perms->table, def_perm);
1264                         if (perdatum == NULL) {
1265                                 printk(KERN_ERR
1266                                        "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1267                                        def_perm, pol_class);
1268                                 return -EINVAL;
1269                         }
1270                         if (perdatum->value != j + 1) {
1271                                 printk(KERN_ERR
1272                                        "SELinux:  permission %s in class %s has incorrect value\n",
1273                                        def_perm, pol_class);
1274                                 return -EINVAL;
1275                         }
1276                 }
1277         }
1278         return 0;
1279 }
1280
1281 /* Clone the SID into the new SID table. */
1282 static int clone_sid(u32 sid,
1283                      struct context *context,
1284                      void *arg)
1285 {
1286         struct sidtab *s = arg;
1287
1288         return sidtab_insert(s, sid, context);
1289 }
1290
1291 static inline int convert_context_handle_invalid_context(struct context *context)
1292 {
1293         int rc = 0;
1294
1295         if (selinux_enforcing) {
1296                 rc = -EINVAL;
1297         } else {
1298                 char *s;
1299                 u32 len;
1300
1301                 if (!context_struct_to_string(context, &s, &len)) {
1302                         printk(KERN_WARNING
1303                        "SELinux:  Context %s would be invalid if enforcing\n",
1304                                s);
1305                         kfree(s);
1306                 }
1307         }
1308         return rc;
1309 }
1310
1311 struct convert_context_args {
1312         struct policydb *oldp;
1313         struct policydb *newp;
1314 };
1315
1316 /*
1317  * Convert the values in the security context
1318  * structure `c' from the values specified
1319  * in the policy `p->oldp' to the values specified
1320  * in the policy `p->newp'.  Verify that the
1321  * context is valid under the new policy.
1322  */
1323 static int convert_context(u32 key,
1324                            struct context *c,
1325                            void *p)
1326 {
1327         struct convert_context_args *args;
1328         struct context oldc;
1329         struct role_datum *role;
1330         struct type_datum *typdatum;
1331         struct user_datum *usrdatum;
1332         char *s;
1333         u32 len;
1334         int rc;
1335
1336         args = p;
1337
1338         if (c->str) {
1339                 struct context ctx;
1340                 s = kstrdup(c->str, GFP_KERNEL);
1341                 if (!s) {
1342                         rc = -ENOMEM;
1343                         goto out;
1344                 }
1345                 rc = string_to_context_struct(args->newp, NULL, s,
1346                                               c->len, &ctx, SECSID_NULL);
1347                 kfree(s);
1348                 if (!rc) {
1349                         printk(KERN_INFO
1350                        "SELinux:  Context %s became valid (mapped).\n",
1351                                c->str);
1352                         /* Replace string with mapped representation. */
1353                         kfree(c->str);
1354                         memcpy(c, &ctx, sizeof(*c));
1355                         goto out;
1356                 } else if (rc == -EINVAL) {
1357                         /* Retain string representation for later mapping. */
1358                         rc = 0;
1359                         goto out;
1360                 } else {
1361                         /* Other error condition, e.g. ENOMEM. */
1362                         printk(KERN_ERR
1363                        "SELinux:   Unable to map context %s, rc = %d.\n",
1364                                c->str, -rc);
1365                         goto out;
1366                 }
1367         }
1368
1369         rc = context_cpy(&oldc, c);
1370         if (rc)
1371                 goto out;
1372
1373         rc = -EINVAL;
1374
1375         /* Convert the user. */
1376         usrdatum = hashtab_search(args->newp->p_users.table,
1377                                   args->oldp->p_user_val_to_name[c->user - 1]);
1378         if (!usrdatum)
1379                 goto bad;
1380         c->user = usrdatum->value;
1381
1382         /* Convert the role. */
1383         role = hashtab_search(args->newp->p_roles.table,
1384                               args->oldp->p_role_val_to_name[c->role - 1]);
1385         if (!role)
1386                 goto bad;
1387         c->role = role->value;
1388
1389         /* Convert the type. */
1390         typdatum = hashtab_search(args->newp->p_types.table,
1391                                   args->oldp->p_type_val_to_name[c->type - 1]);
1392         if (!typdatum)
1393                 goto bad;
1394         c->type = typdatum->value;
1395
1396         rc = mls_convert_context(args->oldp, args->newp, c);
1397         if (rc)
1398                 goto bad;
1399
1400         /* Check the validity of the new context. */
1401         if (!policydb_context_isvalid(args->newp, c)) {
1402                 rc = convert_context_handle_invalid_context(&oldc);
1403                 if (rc)
1404                         goto bad;
1405         }
1406
1407         context_destroy(&oldc);
1408         rc = 0;
1409 out:
1410         return rc;
1411 bad:
1412         /* Map old representation to string and save it. */
1413         if (context_struct_to_string(&oldc, &s, &len))
1414                 return -ENOMEM;
1415         context_destroy(&oldc);
1416         context_destroy(c);
1417         c->str = s;
1418         c->len = len;
1419         printk(KERN_INFO
1420                "SELinux:  Context %s became invalid (unmapped).\n",
1421                c->str);
1422         rc = 0;
1423         goto out;
1424 }
1425
1426 static void security_load_policycaps(void)
1427 {
1428         selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1429                                                   POLICYDB_CAPABILITY_NETPEER);
1430         selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1431                                                   POLICYDB_CAPABILITY_OPENPERM);
1432 }
1433
1434 extern void selinux_complete_init(void);
1435 static int security_preserve_bools(struct policydb *p);
1436
1437 /**
1438  * security_load_policy - Load a security policy configuration.
1439  * @data: binary policy data
1440  * @len: length of data in bytes
1441  *
1442  * Load a new set of security policy configuration data,
1443  * validate it and convert the SID table as necessary.
1444  * This function will flush the access vector cache after
1445  * loading the new policy.
1446  */
1447 int security_load_policy(void *data, size_t len)
1448 {
1449         struct policydb oldpolicydb, newpolicydb;
1450         struct sidtab oldsidtab, newsidtab;
1451         struct convert_context_args args;
1452         u32 seqno;
1453         int rc = 0;
1454         struct policy_file file = { data, len }, *fp = &file;
1455
1456         mutex_lock(&load_mutex);
1457
1458         if (!ss_initialized) {
1459                 avtab_cache_init();
1460                 if (policydb_read(&policydb, fp)) {
1461                         mutex_unlock(&load_mutex);
1462                         avtab_cache_destroy();
1463                         return -EINVAL;
1464                 }
1465                 if (policydb_load_isids(&policydb, &sidtab)) {
1466                         mutex_unlock(&load_mutex);
1467                         policydb_destroy(&policydb);
1468                         avtab_cache_destroy();
1469                         return -EINVAL;
1470                 }
1471                 /* Verify that the kernel defined classes are correct. */
1472                 if (validate_classes(&policydb)) {
1473                         printk(KERN_ERR
1474                                "SELinux:  the definition of a class is incorrect\n");
1475                         mutex_unlock(&load_mutex);
1476                         sidtab_destroy(&sidtab);
1477                         policydb_destroy(&policydb);
1478                         avtab_cache_destroy();
1479                         return -EINVAL;
1480                 }
1481                 security_load_policycaps();
1482                 policydb_loaded_version = policydb.policyvers;
1483                 ss_initialized = 1;
1484                 seqno = ++latest_granting;
1485                 mutex_unlock(&load_mutex);
1486                 selinux_complete_init();
1487                 avc_ss_reset(seqno);
1488                 selnl_notify_policyload(seqno);
1489                 selinux_netlbl_cache_invalidate();
1490                 selinux_xfrm_notify_policyload();
1491                 return 0;
1492         }
1493
1494 #if 0
1495         sidtab_hash_eval(&sidtab, "sids");
1496 #endif
1497
1498         if (policydb_read(&newpolicydb, fp)) {
1499                 mutex_unlock(&load_mutex);
1500                 return -EINVAL;
1501         }
1502
1503         if (sidtab_init(&newsidtab)) {
1504                 mutex_unlock(&load_mutex);
1505                 policydb_destroy(&newpolicydb);
1506                 return -ENOMEM;
1507         }
1508
1509         /* Verify that the kernel defined classes are correct. */
1510         if (validate_classes(&newpolicydb)) {
1511                 printk(KERN_ERR
1512                        "SELinux:  the definition of a class is incorrect\n");
1513                 rc = -EINVAL;
1514                 goto err;
1515         }
1516
1517         rc = security_preserve_bools(&newpolicydb);
1518         if (rc) {
1519                 printk(KERN_ERR "SELinux:  unable to preserve booleans\n");
1520                 goto err;
1521         }
1522
1523         /* Clone the SID table. */
1524         sidtab_shutdown(&sidtab);
1525         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1526                 rc = -ENOMEM;
1527                 goto err;
1528         }
1529
1530         /*
1531          * Convert the internal representations of contexts
1532          * in the new SID table.
1533          */
1534         args.oldp = &policydb;
1535         args.newp = &newpolicydb;
1536         rc = sidtab_map(&newsidtab, convert_context, &args);
1537         if (rc)
1538                 goto err;
1539
1540         /* Save the old policydb and SID table to free later. */
1541         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1542         sidtab_set(&oldsidtab, &sidtab);
1543
1544         /* Install the new policydb and SID table. */
1545         write_lock_irq(&policy_rwlock);
1546         memcpy(&policydb, &newpolicydb, sizeof policydb);
1547         sidtab_set(&sidtab, &newsidtab);
1548         security_load_policycaps();
1549         seqno = ++latest_granting;
1550         policydb_loaded_version = policydb.policyvers;
1551         write_unlock_irq(&policy_rwlock);
1552         mutex_unlock(&load_mutex);
1553
1554         /* Free the old policydb and SID table. */
1555         policydb_destroy(&oldpolicydb);
1556         sidtab_destroy(&oldsidtab);
1557
1558         avc_ss_reset(seqno);
1559         selnl_notify_policyload(seqno);
1560         selinux_netlbl_cache_invalidate();
1561         selinux_xfrm_notify_policyload();
1562
1563         return 0;
1564
1565 err:
1566         mutex_unlock(&load_mutex);
1567         sidtab_destroy(&newsidtab);
1568         policydb_destroy(&newpolicydb);
1569         return rc;
1570
1571 }
1572
1573 /**
1574  * security_port_sid - Obtain the SID for a port.
1575  * @protocol: protocol number
1576  * @port: port number
1577  * @out_sid: security identifier
1578  */
1579 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1580 {
1581         struct ocontext *c;
1582         int rc = 0;
1583
1584         read_lock(&policy_rwlock);
1585
1586         c = policydb.ocontexts[OCON_PORT];
1587         while (c) {
1588                 if (c->u.port.protocol == protocol &&
1589                     c->u.port.low_port <= port &&
1590                     c->u.port.high_port >= port)
1591                         break;
1592                 c = c->next;
1593         }
1594
1595         if (c) {
1596                 if (!c->sid[0]) {
1597                         rc = sidtab_context_to_sid(&sidtab,
1598                                                    &c->context[0],
1599                                                    &c->sid[0]);
1600                         if (rc)
1601                                 goto out;
1602                 }
1603                 *out_sid = c->sid[0];
1604         } else {
1605                 *out_sid = SECINITSID_PORT;
1606         }
1607
1608 out:
1609         read_unlock(&policy_rwlock);
1610         return rc;
1611 }
1612
1613 /**
1614  * security_netif_sid - Obtain the SID for a network interface.
1615  * @name: interface name
1616  * @if_sid: interface SID
1617  */
1618 int security_netif_sid(char *name, u32 *if_sid)
1619 {
1620         int rc = 0;
1621         struct ocontext *c;
1622
1623         read_lock(&policy_rwlock);
1624
1625         c = policydb.ocontexts[OCON_NETIF];
1626         while (c) {
1627                 if (strcmp(name, c->u.name) == 0)
1628                         break;
1629                 c = c->next;
1630         }
1631
1632         if (c) {
1633                 if (!c->sid[0] || !c->sid[1]) {
1634                         rc = sidtab_context_to_sid(&sidtab,
1635                                                   &c->context[0],
1636                                                   &c->sid[0]);
1637                         if (rc)
1638                                 goto out;
1639                         rc = sidtab_context_to_sid(&sidtab,
1640                                                    &c->context[1],
1641                                                    &c->sid[1]);
1642                         if (rc)
1643                                 goto out;
1644                 }
1645                 *if_sid = c->sid[0];
1646         } else
1647                 *if_sid = SECINITSID_NETIF;
1648
1649 out:
1650         read_unlock(&policy_rwlock);
1651         return rc;
1652 }
1653
1654 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1655 {
1656         int i, fail = 0;
1657
1658         for (i = 0; i < 4; i++)
1659                 if (addr[i] != (input[i] & mask[i])) {
1660                         fail = 1;
1661                         break;
1662                 }
1663
1664         return !fail;
1665 }
1666
1667 /**
1668  * security_node_sid - Obtain the SID for a node (host).
1669  * @domain: communication domain aka address family
1670  * @addrp: address
1671  * @addrlen: address length in bytes
1672  * @out_sid: security identifier
1673  */
1674 int security_node_sid(u16 domain,
1675                       void *addrp,
1676                       u32 addrlen,
1677                       u32 *out_sid)
1678 {
1679         int rc = 0;
1680         struct ocontext *c;
1681
1682         read_lock(&policy_rwlock);
1683
1684         switch (domain) {
1685         case AF_INET: {
1686                 u32 addr;
1687
1688                 if (addrlen != sizeof(u32)) {
1689                         rc = -EINVAL;
1690                         goto out;
1691                 }
1692
1693                 addr = *((u32 *)addrp);
1694
1695                 c = policydb.ocontexts[OCON_NODE];
1696                 while (c) {
1697                         if (c->u.node.addr == (addr & c->u.node.mask))
1698                                 break;
1699                         c = c->next;
1700                 }
1701                 break;
1702         }
1703
1704         case AF_INET6:
1705                 if (addrlen != sizeof(u64) * 2) {
1706                         rc = -EINVAL;
1707                         goto out;
1708                 }
1709                 c = policydb.ocontexts[OCON_NODE6];
1710                 while (c) {
1711                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1712                                                 c->u.node6.mask))
1713                                 break;
1714                         c = c->next;
1715                 }
1716                 break;
1717
1718         default:
1719                 *out_sid = SECINITSID_NODE;
1720                 goto out;
1721         }
1722
1723         if (c) {
1724                 if (!c->sid[0]) {
1725                         rc = sidtab_context_to_sid(&sidtab,
1726                                                    &c->context[0],
1727                                                    &c->sid[0]);
1728                         if (rc)
1729                                 goto out;
1730                 }
1731                 *out_sid = c->sid[0];
1732         } else {
1733                 *out_sid = SECINITSID_NODE;
1734         }
1735
1736 out:
1737         read_unlock(&policy_rwlock);
1738         return rc;
1739 }
1740
1741 #define SIDS_NEL 25
1742
1743 /**
1744  * security_get_user_sids - Obtain reachable SIDs for a user.
1745  * @fromsid: starting SID
1746  * @username: username
1747  * @sids: array of reachable SIDs for user
1748  * @nel: number of elements in @sids
1749  *
1750  * Generate the set of SIDs for legal security contexts
1751  * for a given user that can be reached by @fromsid.
1752  * Set *@sids to point to a dynamically allocated
1753  * array containing the set of SIDs.  Set *@nel to the
1754  * number of elements in the array.
1755  */
1756
1757 int security_get_user_sids(u32 fromsid,
1758                            char *username,
1759                            u32 **sids,
1760                            u32 *nel)
1761 {
1762         struct context *fromcon, usercon;
1763         u32 *mysids = NULL, *mysids2, sid;
1764         u32 mynel = 0, maxnel = SIDS_NEL;
1765         struct user_datum *user;
1766         struct role_datum *role;
1767         struct ebitmap_node *rnode, *tnode;
1768         int rc = 0, i, j;
1769
1770         *sids = NULL;
1771         *nel = 0;
1772
1773         if (!ss_initialized)
1774                 goto out;
1775
1776         read_lock(&policy_rwlock);
1777
1778         context_init(&usercon);
1779
1780         fromcon = sidtab_search(&sidtab, fromsid);
1781         if (!fromcon) {
1782                 rc = -EINVAL;
1783                 goto out_unlock;
1784         }
1785
1786         user = hashtab_search(policydb.p_users.table, username);
1787         if (!user) {
1788                 rc = -EINVAL;
1789                 goto out_unlock;
1790         }
1791         usercon.user = user->value;
1792
1793         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1794         if (!mysids) {
1795                 rc = -ENOMEM;
1796                 goto out_unlock;
1797         }
1798
1799         ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
1800                 role = policydb.role_val_to_struct[i];
1801                 usercon.role = i+1;
1802                 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
1803                         usercon.type = j+1;
1804
1805                         if (mls_setup_user_range(fromcon, user, &usercon))
1806                                 continue;
1807
1808                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1809                         if (rc)
1810                                 goto out_unlock;
1811                         if (mynel < maxnel) {
1812                                 mysids[mynel++] = sid;
1813                         } else {
1814                                 maxnel += SIDS_NEL;
1815                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1816                                 if (!mysids2) {
1817                                         rc = -ENOMEM;
1818                                         goto out_unlock;
1819                                 }
1820                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1821                                 kfree(mysids);
1822                                 mysids = mysids2;
1823                                 mysids[mynel++] = sid;
1824                         }
1825                 }
1826         }
1827
1828 out_unlock:
1829         read_unlock(&policy_rwlock);
1830         if (rc || !mynel) {
1831                 kfree(mysids);
1832                 goto out;
1833         }
1834
1835         mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
1836         if (!mysids2) {
1837                 rc = -ENOMEM;
1838                 kfree(mysids);
1839                 goto out;
1840         }
1841         for (i = 0, j = 0; i < mynel; i++) {
1842                 rc = avc_has_perm_noaudit(fromsid, mysids[i],
1843                                           SECCLASS_PROCESS,
1844                                           PROCESS__TRANSITION, AVC_STRICT,
1845                                           NULL);
1846                 if (!rc)
1847                         mysids2[j++] = mysids[i];
1848                 cond_resched();
1849         }
1850         rc = 0;
1851         kfree(mysids);
1852         *sids = mysids2;
1853         *nel = j;
1854 out:
1855         return rc;
1856 }
1857
1858 /**
1859  * security_genfs_sid - Obtain a SID for a file in a filesystem
1860  * @fstype: filesystem type
1861  * @path: path from root of mount
1862  * @sclass: file security class
1863  * @sid: SID for path
1864  *
1865  * Obtain a SID to use for a file in a filesystem that
1866  * cannot support xattr or use a fixed labeling behavior like
1867  * transition SIDs or task SIDs.
1868  */
1869 int security_genfs_sid(const char *fstype,
1870                        char *path,
1871                        u16 sclass,
1872                        u32 *sid)
1873 {
1874         int len;
1875         struct genfs *genfs;
1876         struct ocontext *c;
1877         int rc = 0, cmp = 0;
1878
1879         while (path[0] == '/' && path[1] == '/')
1880                 path++;
1881
1882         read_lock(&policy_rwlock);
1883
1884         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1885                 cmp = strcmp(fstype, genfs->fstype);
1886                 if (cmp <= 0)
1887                         break;
1888         }
1889
1890         if (!genfs || cmp) {
1891                 *sid = SECINITSID_UNLABELED;
1892                 rc = -ENOENT;
1893                 goto out;
1894         }
1895
1896         for (c = genfs->head; c; c = c->next) {
1897                 len = strlen(c->u.name);
1898                 if ((!c->v.sclass || sclass == c->v.sclass) &&
1899                     (strncmp(c->u.name, path, len) == 0))
1900                         break;
1901         }
1902
1903         if (!c) {
1904                 *sid = SECINITSID_UNLABELED;
1905                 rc = -ENOENT;
1906                 goto out;
1907         }
1908
1909         if (!c->sid[0]) {
1910                 rc = sidtab_context_to_sid(&sidtab,
1911                                            &c->context[0],
1912                                            &c->sid[0]);
1913                 if (rc)
1914                         goto out;
1915         }
1916
1917         *sid = c->sid[0];
1918 out:
1919         read_unlock(&policy_rwlock);
1920         return rc;
1921 }
1922
1923 /**
1924  * security_fs_use - Determine how to handle labeling for a filesystem.
1925  * @fstype: filesystem type
1926  * @behavior: labeling behavior
1927  * @sid: SID for filesystem (superblock)
1928  */
1929 int security_fs_use(
1930         const char *fstype,
1931         unsigned int *behavior,
1932         u32 *sid)
1933 {
1934         int rc = 0;
1935         struct ocontext *c;
1936
1937         read_lock(&policy_rwlock);
1938
1939         c = policydb.ocontexts[OCON_FSUSE];
1940         while (c) {
1941                 if (strcmp(fstype, c->u.name) == 0)
1942                         break;
1943                 c = c->next;
1944         }
1945
1946         if (c) {
1947                 *behavior = c->v.behavior;
1948                 if (!c->sid[0]) {
1949                         rc = sidtab_context_to_sid(&sidtab,
1950                                                    &c->context[0],
1951                                                    &c->sid[0]);
1952                         if (rc)
1953                                 goto out;
1954                 }
1955                 *sid = c->sid[0];
1956         } else {
1957                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1958                 if (rc) {
1959                         *behavior = SECURITY_FS_USE_NONE;
1960                         rc = 0;
1961                 } else {
1962                         *behavior = SECURITY_FS_USE_GENFS;
1963                 }
1964         }
1965
1966 out:
1967         read_unlock(&policy_rwlock);
1968         return rc;
1969 }
1970
1971 int security_get_bools(int *len, char ***names, int **values)
1972 {
1973         int i, rc = -ENOMEM;
1974
1975         read_lock(&policy_rwlock);
1976         *names = NULL;
1977         *values = NULL;
1978
1979         *len = policydb.p_bools.nprim;
1980         if (!*len) {
1981                 rc = 0;
1982                 goto out;
1983         }
1984
1985        *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
1986         if (!*names)
1987                 goto err;
1988
1989        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
1990         if (!*values)
1991                 goto err;
1992
1993         for (i = 0; i < *len; i++) {
1994                 size_t name_len;
1995                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1996                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1997                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1998                 if (!(*names)[i])
1999                         goto err;
2000                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
2001                 (*names)[i][name_len - 1] = 0;
2002         }
2003         rc = 0;
2004 out:
2005         read_unlock(&policy_rwlock);
2006         return rc;
2007 err:
2008         if (*names) {
2009                 for (i = 0; i < *len; i++)
2010                         kfree((*names)[i]);
2011         }
2012         kfree(*values);
2013         goto out;
2014 }
2015
2016
2017 int security_set_bools(int len, int *values)
2018 {
2019         int i, rc = 0;
2020         int lenp, seqno = 0;
2021         struct cond_node *cur;
2022
2023         write_lock_irq(&policy_rwlock);
2024
2025         lenp = policydb.p_bools.nprim;
2026         if (len != lenp) {
2027                 rc = -EFAULT;
2028                 goto out;
2029         }
2030
2031         for (i = 0; i < len; i++) {
2032                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2033                         audit_log(current->audit_context, GFP_ATOMIC,
2034                                 AUDIT_MAC_CONFIG_CHANGE,
2035                                 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2036                                 policydb.p_bool_val_to_name[i],
2037                                 !!values[i],
2038                                 policydb.bool_val_to_struct[i]->state,
2039                                 audit_get_loginuid(current),
2040                                 audit_get_sessionid(current));
2041                 }
2042                 if (values[i])
2043                         policydb.bool_val_to_struct[i]->state = 1;
2044                 else
2045                         policydb.bool_val_to_struct[i]->state = 0;
2046         }
2047
2048         for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
2049                 rc = evaluate_cond_node(&policydb, cur);
2050                 if (rc)
2051                         goto out;
2052         }
2053
2054         seqno = ++latest_granting;
2055
2056 out:
2057         write_unlock_irq(&policy_rwlock);
2058         if (!rc) {
2059                 avc_ss_reset(seqno);
2060                 selnl_notify_policyload(seqno);
2061                 selinux_xfrm_notify_policyload();
2062         }
2063         return rc;
2064 }
2065
2066 int security_get_bool_value(int bool)
2067 {
2068         int rc = 0;
2069         int len;
2070
2071         read_lock(&policy_rwlock);
2072
2073         len = policydb.p_bools.nprim;
2074         if (bool >= len) {
2075                 rc = -EFAULT;
2076                 goto out;
2077         }
2078
2079         rc = policydb.bool_val_to_struct[bool]->state;
2080 out:
2081         read_unlock(&policy_rwlock);
2082         return rc;
2083 }
2084
2085 static int security_preserve_bools(struct policydb *p)
2086 {
2087         int rc, nbools = 0, *bvalues = NULL, i;
2088         char **bnames = NULL;
2089         struct cond_bool_datum *booldatum;
2090         struct cond_node *cur;
2091
2092         rc = security_get_bools(&nbools, &bnames, &bvalues);
2093         if (rc)
2094                 goto out;
2095         for (i = 0; i < nbools; i++) {
2096                 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2097                 if (booldatum)
2098                         booldatum->state = bvalues[i];
2099         }
2100         for (cur = p->cond_list; cur != NULL; cur = cur->next) {
2101                 rc = evaluate_cond_node(p, cur);
2102                 if (rc)
2103                         goto out;
2104         }
2105
2106 out:
2107         if (bnames) {
2108                 for (i = 0; i < nbools; i++)
2109                         kfree(bnames[i]);
2110         }
2111         kfree(bnames);
2112         kfree(bvalues);
2113         return rc;
2114 }
2115
2116 /*
2117  * security_sid_mls_copy() - computes a new sid based on the given
2118  * sid and the mls portion of mls_sid.
2119  */
2120 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2121 {
2122         struct context *context1;
2123         struct context *context2;
2124         struct context newcon;
2125         char *s;
2126         u32 len;
2127         int rc = 0;
2128
2129         if (!ss_initialized || !selinux_mls_enabled) {
2130                 *new_sid = sid;
2131                 goto out;
2132         }
2133
2134         context_init(&newcon);
2135
2136         read_lock(&policy_rwlock);
2137         context1 = sidtab_search(&sidtab, sid);
2138         if (!context1) {
2139                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2140                         __func__, sid);
2141                 rc = -EINVAL;
2142                 goto out_unlock;
2143         }
2144
2145         context2 = sidtab_search(&sidtab, mls_sid);
2146         if (!context2) {
2147                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2148                         __func__, mls_sid);
2149                 rc = -EINVAL;
2150                 goto out_unlock;
2151         }
2152
2153         newcon.user = context1->user;
2154         newcon.role = context1->role;
2155         newcon.type = context1->type;
2156         rc = mls_context_cpy(&newcon, context2);
2157         if (rc)
2158                 goto out_unlock;
2159
2160         /* Check the validity of the new context. */
2161         if (!policydb_context_isvalid(&policydb, &newcon)) {
2162                 rc = convert_context_handle_invalid_context(&newcon);
2163                 if (rc)
2164                         goto bad;
2165         }
2166
2167         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2168         goto out_unlock;
2169
2170 bad:
2171         if (!context_struct_to_string(&newcon, &s, &len)) {
2172                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2173                           "security_sid_mls_copy: invalid context %s", s);
2174                 kfree(s);
2175         }
2176
2177 out_unlock:
2178         read_unlock(&policy_rwlock);
2179         context_destroy(&newcon);
2180 out:
2181         return rc;
2182 }
2183
2184 /**
2185  * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2186  * @nlbl_sid: NetLabel SID
2187  * @nlbl_type: NetLabel labeling protocol type
2188  * @xfrm_sid: XFRM SID
2189  *
2190  * Description:
2191  * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2192  * resolved into a single SID it is returned via @peer_sid and the function
2193  * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
2194  * returns a negative value.  A table summarizing the behavior is below:
2195  *
2196  *                                 | function return |      @sid
2197  *   ------------------------------+-----------------+-----------------
2198  *   no peer labels                |        0        |    SECSID_NULL
2199  *   single peer label             |        0        |    <peer_label>
2200  *   multiple, consistent labels   |        0        |    <peer_label>
2201  *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
2202  *
2203  */
2204 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2205                                  u32 xfrm_sid,
2206                                  u32 *peer_sid)
2207 {
2208         int rc;
2209         struct context *nlbl_ctx;
2210         struct context *xfrm_ctx;
2211
2212         /* handle the common (which also happens to be the set of easy) cases
2213          * right away, these two if statements catch everything involving a
2214          * single or absent peer SID/label */
2215         if (xfrm_sid == SECSID_NULL) {
2216                 *peer_sid = nlbl_sid;
2217                 return 0;
2218         }
2219         /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2220          * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2221          * is present */
2222         if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2223                 *peer_sid = xfrm_sid;
2224                 return 0;
2225         }
2226
2227         /* we don't need to check ss_initialized here since the only way both
2228          * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2229          * security server was initialized and ss_initialized was true */
2230         if (!selinux_mls_enabled) {
2231                 *peer_sid = SECSID_NULL;
2232                 return 0;
2233         }
2234
2235         read_lock(&policy_rwlock);
2236
2237         nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2238         if (!nlbl_ctx) {
2239                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2240                        __func__, nlbl_sid);
2241                 rc = -EINVAL;
2242                 goto out_slowpath;
2243         }
2244         xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2245         if (!xfrm_ctx) {
2246                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2247                        __func__, xfrm_sid);
2248                 rc = -EINVAL;
2249                 goto out_slowpath;
2250         }
2251         rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2252
2253 out_slowpath:
2254         read_unlock(&policy_rwlock);
2255         if (rc == 0)
2256                 /* at present NetLabel SIDs/labels really only carry MLS
2257                  * information so if the MLS portion of the NetLabel SID
2258                  * matches the MLS portion of the labeled XFRM SID/label
2259                  * then pass along the XFRM SID as it is the most
2260                  * expressive */
2261                 *peer_sid = xfrm_sid;
2262         else
2263                 *peer_sid = SECSID_NULL;
2264         return rc;
2265 }
2266
2267 static int get_classes_callback(void *k, void *d, void *args)
2268 {
2269         struct class_datum *datum = d;
2270         char *name = k, **classes = args;
2271         int value = datum->value - 1;
2272
2273         classes[value] = kstrdup(name, GFP_ATOMIC);
2274         if (!classes[value])
2275                 return -ENOMEM;
2276
2277         return 0;
2278 }
2279
2280 int security_get_classes(char ***classes, int *nclasses)
2281 {
2282         int rc = -ENOMEM;
2283
2284         read_lock(&policy_rwlock);
2285
2286         *nclasses = policydb.p_classes.nprim;
2287         *classes = kcalloc(*nclasses, sizeof(*classes), GFP_ATOMIC);
2288         if (!*classes)
2289                 goto out;
2290
2291         rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2292                         *classes);
2293         if (rc < 0) {
2294                 int i;
2295                 for (i = 0; i < *nclasses; i++)
2296                         kfree((*classes)[i]);
2297                 kfree(*classes);
2298         }
2299
2300 out:
2301         read_unlock(&policy_rwlock);
2302         return rc;
2303 }
2304
2305 static int get_permissions_callback(void *k, void *d, void *args)
2306 {
2307         struct perm_datum *datum = d;
2308         char *name = k, **perms = args;
2309         int value = datum->value - 1;
2310
2311         perms[value] = kstrdup(name, GFP_ATOMIC);
2312         if (!perms[value])
2313                 return -ENOMEM;
2314
2315         return 0;
2316 }
2317
2318 int security_get_permissions(char *class, char ***perms, int *nperms)
2319 {
2320         int rc = -ENOMEM, i;
2321         struct class_datum *match;
2322
2323         read_lock(&policy_rwlock);
2324
2325         match = hashtab_search(policydb.p_classes.table, class);
2326         if (!match) {
2327                 printk(KERN_ERR "SELinux: %s:  unrecognized class %s\n",
2328                         __func__, class);
2329                 rc = -EINVAL;
2330                 goto out;
2331         }
2332
2333         *nperms = match->permissions.nprim;
2334         *perms = kcalloc(*nperms, sizeof(*perms), GFP_ATOMIC);
2335         if (!*perms)
2336                 goto out;
2337
2338         if (match->comdatum) {
2339                 rc = hashtab_map(match->comdatum->permissions.table,
2340                                 get_permissions_callback, *perms);
2341                 if (rc < 0)
2342                         goto err;
2343         }
2344
2345         rc = hashtab_map(match->permissions.table, get_permissions_callback,
2346                         *perms);
2347         if (rc < 0)
2348                 goto err;
2349
2350 out:
2351         read_unlock(&policy_rwlock);
2352         return rc;
2353
2354 err:
2355         read_unlock(&policy_rwlock);
2356         for (i = 0; i < *nperms; i++)
2357                 kfree((*perms)[i]);
2358         kfree(*perms);
2359         return rc;
2360 }
2361
2362 int security_get_reject_unknown(void)
2363 {
2364         return policydb.reject_unknown;
2365 }
2366
2367 int security_get_allow_unknown(void)
2368 {
2369         return policydb.allow_unknown;
2370 }
2371
2372 /**
2373  * security_policycap_supported - Check for a specific policy capability
2374  * @req_cap: capability
2375  *
2376  * Description:
2377  * This function queries the currently loaded policy to see if it supports the
2378  * capability specified by @req_cap.  Returns true (1) if the capability is
2379  * supported, false (0) if it isn't supported.
2380  *
2381  */
2382 int security_policycap_supported(unsigned int req_cap)
2383 {
2384         int rc;
2385
2386         read_lock(&policy_rwlock);
2387         rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2388         read_unlock(&policy_rwlock);
2389
2390         return rc;
2391 }
2392
2393 struct selinux_audit_rule {
2394         u32 au_seqno;
2395         struct context au_ctxt;
2396 };
2397
2398 void selinux_audit_rule_free(void *vrule)
2399 {
2400         struct selinux_audit_rule *rule = vrule;
2401
2402         if (rule) {
2403                 context_destroy(&rule->au_ctxt);
2404                 kfree(rule);
2405         }
2406 }
2407
2408 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2409 {
2410         struct selinux_audit_rule *tmprule;
2411         struct role_datum *roledatum;
2412         struct type_datum *typedatum;
2413         struct user_datum *userdatum;
2414         struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2415         int rc = 0;
2416
2417         *rule = NULL;
2418
2419         if (!ss_initialized)
2420                 return -EOPNOTSUPP;
2421
2422         switch (field) {
2423         case AUDIT_SUBJ_USER:
2424         case AUDIT_SUBJ_ROLE:
2425         case AUDIT_SUBJ_TYPE:
2426         case AUDIT_OBJ_USER:
2427         case AUDIT_OBJ_ROLE:
2428         case AUDIT_OBJ_TYPE:
2429                 /* only 'equals' and 'not equals' fit user, role, and type */
2430                 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2431                         return -EINVAL;
2432                 break;
2433         case AUDIT_SUBJ_SEN:
2434         case AUDIT_SUBJ_CLR:
2435         case AUDIT_OBJ_LEV_LOW:
2436         case AUDIT_OBJ_LEV_HIGH:
2437                 /* we do not allow a range, indicated by the presense of '-' */
2438                 if (strchr(rulestr, '-'))
2439                         return -EINVAL;
2440                 break;
2441         default:
2442                 /* only the above fields are valid */
2443                 return -EINVAL;
2444         }
2445
2446         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2447         if (!tmprule)
2448                 return -ENOMEM;
2449
2450         context_init(&tmprule->au_ctxt);
2451
2452         read_lock(&policy_rwlock);
2453
2454         tmprule->au_seqno = latest_granting;
2455
2456         switch (field) {
2457         case AUDIT_SUBJ_USER:
2458         case AUDIT_OBJ_USER:
2459                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2460                 if (!userdatum)
2461                         rc = -EINVAL;
2462                 else
2463                         tmprule->au_ctxt.user = userdatum->value;
2464                 break;
2465         case AUDIT_SUBJ_ROLE:
2466         case AUDIT_OBJ_ROLE:
2467                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2468                 if (!roledatum)
2469                         rc = -EINVAL;
2470                 else
2471                         tmprule->au_ctxt.role = roledatum->value;
2472                 break;
2473         case AUDIT_SUBJ_TYPE:
2474         case AUDIT_OBJ_TYPE:
2475                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2476                 if (!typedatum)
2477                         rc = -EINVAL;
2478                 else
2479                         tmprule->au_ctxt.type = typedatum->value;
2480                 break;
2481         case AUDIT_SUBJ_SEN:
2482         case AUDIT_SUBJ_CLR:
2483         case AUDIT_OBJ_LEV_LOW:
2484         case AUDIT_OBJ_LEV_HIGH:
2485                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2486                 break;
2487         }
2488
2489         read_unlock(&policy_rwlock);
2490
2491         if (rc) {
2492                 selinux_audit_rule_free(tmprule);
2493                 tmprule = NULL;
2494         }
2495
2496         *rule = tmprule;
2497
2498         return rc;
2499 }
2500
2501 /* Check to see if the rule contains any selinux fields */
2502 int selinux_audit_rule_known(struct audit_krule *rule)
2503 {
2504         int i;
2505
2506         for (i = 0; i < rule->field_count; i++) {
2507                 struct audit_field *f = &rule->fields[i];
2508                 switch (f->type) {
2509                 case AUDIT_SUBJ_USER:
2510                 case AUDIT_SUBJ_ROLE:
2511                 case AUDIT_SUBJ_TYPE:
2512                 case AUDIT_SUBJ_SEN:
2513                 case AUDIT_SUBJ_CLR:
2514                 case AUDIT_OBJ_USER:
2515                 case AUDIT_OBJ_ROLE:
2516                 case AUDIT_OBJ_TYPE:
2517                 case AUDIT_OBJ_LEV_LOW:
2518                 case AUDIT_OBJ_LEV_HIGH:
2519                         return 1;
2520                 }
2521         }
2522
2523         return 0;
2524 }
2525
2526 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2527                              struct audit_context *actx)
2528 {
2529         struct context *ctxt;
2530         struct mls_level *level;
2531         struct selinux_audit_rule *rule = vrule;
2532         int match = 0;
2533
2534         if (!rule) {
2535                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2536                           "selinux_audit_rule_match: missing rule\n");
2537                 return -ENOENT;
2538         }
2539
2540         read_lock(&policy_rwlock);
2541
2542         if (rule->au_seqno < latest_granting) {
2543                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2544                           "selinux_audit_rule_match: stale rule\n");
2545                 match = -ESTALE;
2546                 goto out;
2547         }
2548
2549         ctxt = sidtab_search(&sidtab, sid);
2550         if (!ctxt) {
2551                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2552                           "selinux_audit_rule_match: unrecognized SID %d\n",
2553                           sid);
2554                 match = -ENOENT;
2555                 goto out;
2556         }
2557
2558         /* a field/op pair that is not caught here will simply fall through
2559            without a match */
2560         switch (field) {
2561         case AUDIT_SUBJ_USER:
2562         case AUDIT_OBJ_USER:
2563                 switch (op) {
2564                 case AUDIT_EQUAL:
2565                         match = (ctxt->user == rule->au_ctxt.user);
2566                         break;
2567                 case AUDIT_NOT_EQUAL:
2568                         match = (ctxt->user != rule->au_ctxt.user);
2569                         break;
2570                 }
2571                 break;
2572         case AUDIT_SUBJ_ROLE:
2573         case AUDIT_OBJ_ROLE:
2574                 switch (op) {
2575                 case AUDIT_EQUAL:
2576                         match = (ctxt->role == rule->au_ctxt.role);
2577                         break;
2578                 case AUDIT_NOT_EQUAL:
2579                         match = (ctxt->role != rule->au_ctxt.role);
2580                         break;
2581                 }
2582                 break;
2583         case AUDIT_SUBJ_TYPE:
2584         case AUDIT_OBJ_TYPE:
2585                 switch (op) {
2586                 case AUDIT_EQUAL:
2587                         match = (ctxt->type == rule->au_ctxt.type);
2588                         break;
2589                 case AUDIT_NOT_EQUAL:
2590                         match = (ctxt->type != rule->au_ctxt.type);
2591                         break;
2592                 }
2593                 break;
2594         case AUDIT_SUBJ_SEN:
2595         case AUDIT_SUBJ_CLR:
2596         case AUDIT_OBJ_LEV_LOW:
2597         case AUDIT_OBJ_LEV_HIGH:
2598                 level = ((field == AUDIT_SUBJ_SEN ||
2599                           field == AUDIT_OBJ_LEV_LOW) ?
2600                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2601                 switch (op) {
2602                 case AUDIT_EQUAL:
2603                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2604                                              level);
2605                         break;
2606                 case AUDIT_NOT_EQUAL:
2607                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2608                                               level);
2609                         break;
2610                 case AUDIT_LESS_THAN:
2611                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2612                                                level) &&
2613                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2614                                                level));
2615                         break;
2616                 case AUDIT_LESS_THAN_OR_EQUAL:
2617                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2618                                               level);
2619                         break;
2620                 case AUDIT_GREATER_THAN:
2621                         match = (mls_level_dom(level,
2622                                               &rule->au_ctxt.range.level[0]) &&
2623                                  !mls_level_eq(level,
2624                                                &rule->au_ctxt.range.level[0]));
2625                         break;
2626                 case AUDIT_GREATER_THAN_OR_EQUAL:
2627                         match = mls_level_dom(level,
2628                                               &rule->au_ctxt.range.level[0]);
2629                         break;
2630                 }
2631         }
2632
2633 out:
2634         read_unlock(&policy_rwlock);
2635         return match;
2636 }
2637
2638 static int (*aurule_callback)(void) = audit_update_lsm_rules;
2639
2640 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2641                                u16 class, u32 perms, u32 *retained)
2642 {
2643         int err = 0;
2644
2645         if (event == AVC_CALLBACK_RESET && aurule_callback)
2646                 err = aurule_callback();
2647         return err;
2648 }
2649
2650 static int __init aurule_init(void)
2651 {
2652         int err;
2653
2654         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2655                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2656         if (err)
2657                 panic("avc_add_callback() failed, error %d\n", err);
2658
2659         return err;
2660 }
2661 __initcall(aurule_init);
2662
2663 #ifdef CONFIG_NETLABEL
2664 /**
2665  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2666  * @secattr: the NetLabel packet security attributes
2667  * @sid: the SELinux SID
2668  *
2669  * Description:
2670  * Attempt to cache the context in @ctx, which was derived from the packet in
2671  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2672  * already been initialized.
2673  *
2674  */
2675 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2676                                       u32 sid)
2677 {
2678         u32 *sid_cache;
2679
2680         sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
2681         if (sid_cache == NULL)
2682                 return;
2683         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2684         if (secattr->cache == NULL) {
2685                 kfree(sid_cache);
2686                 return;
2687         }
2688
2689         *sid_cache = sid;
2690         secattr->cache->free = kfree;
2691         secattr->cache->data = sid_cache;
2692         secattr->flags |= NETLBL_SECATTR_CACHE;
2693 }
2694
2695 /**
2696  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2697  * @secattr: the NetLabel packet security attributes
2698  * @sid: the SELinux SID
2699  *
2700  * Description:
2701  * Convert the given NetLabel security attributes in @secattr into a
2702  * SELinux SID.  If the @secattr field does not contain a full SELinux
2703  * SID/context then use SECINITSID_NETMSG as the foundation.  If possibile the
2704  * 'cache' field of @secattr is set and the CACHE flag is set; this is to
2705  * allow the @secattr to be used by NetLabel to cache the secattr to SID
2706  * conversion for future lookups.  Returns zero on success, negative values on
2707  * failure.
2708  *
2709  */
2710 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2711                                    u32 *sid)
2712 {
2713         int rc = -EIDRM;
2714         struct context *ctx;
2715         struct context ctx_new;
2716
2717         if (!ss_initialized) {
2718                 *sid = SECSID_NULL;
2719                 return 0;
2720         }
2721
2722         read_lock(&policy_rwlock);
2723
2724         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2725                 *sid = *(u32 *)secattr->cache->data;
2726                 rc = 0;
2727         } else if (secattr->flags & NETLBL_SECATTR_SECID) {
2728                 *sid = secattr->attr.secid;
2729                 rc = 0;
2730         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2731                 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
2732                 if (ctx == NULL)
2733                         goto netlbl_secattr_to_sid_return;
2734
2735                 ctx_new.user = ctx->user;
2736                 ctx_new.role = ctx->role;
2737                 ctx_new.type = ctx->type;
2738                 mls_import_netlbl_lvl(&ctx_new, secattr);
2739                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2740                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2741                                                   secattr->attr.mls.cat) != 0)
2742                                 goto netlbl_secattr_to_sid_return;
2743                         ctx_new.range.level[1].cat.highbit =
2744                                 ctx_new.range.level[0].cat.highbit;
2745                         ctx_new.range.level[1].cat.node =
2746                                 ctx_new.range.level[0].cat.node;
2747                 } else {
2748                         ebitmap_init(&ctx_new.range.level[0].cat);
2749                         ebitmap_init(&ctx_new.range.level[1].cat);
2750                 }
2751                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2752                         goto netlbl_secattr_to_sid_return_cleanup;
2753
2754                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2755                 if (rc != 0)
2756                         goto netlbl_secattr_to_sid_return_cleanup;
2757
2758                 security_netlbl_cache_add(secattr, *sid);
2759
2760                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2761         } else {
2762                 *sid = SECSID_NULL;
2763                 rc = 0;
2764         }
2765
2766 netlbl_secattr_to_sid_return:
2767         read_unlock(&policy_rwlock);
2768         return rc;
2769 netlbl_secattr_to_sid_return_cleanup:
2770         ebitmap_destroy(&ctx_new.range.level[0].cat);
2771         goto netlbl_secattr_to_sid_return;
2772 }
2773
2774 /**
2775  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2776  * @sid: the SELinux SID
2777  * @secattr: the NetLabel packet security attributes
2778  *
2779  * Description:
2780  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2781  * Returns zero on success, negative values on failure.
2782  *
2783  */
2784 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2785 {
2786         int rc = -ENOENT;
2787         struct context *ctx;
2788
2789         if (!ss_initialized)
2790                 return 0;
2791
2792         read_lock(&policy_rwlock);
2793         ctx = sidtab_search(&sidtab, sid);
2794         if (ctx == NULL)
2795                 goto netlbl_sid_to_secattr_failure;
2796         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2797                                   GFP_ATOMIC);
2798         secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY;
2799         mls_export_netlbl_lvl(ctx, secattr);
2800         rc = mls_export_netlbl_cat(ctx, secattr);
2801         if (rc != 0)
2802                 goto netlbl_sid_to_secattr_failure;
2803         read_unlock(&policy_rwlock);
2804
2805         return 0;
2806
2807 netlbl_sid_to_secattr_failure:
2808         read_unlock(&policy_rwlock);
2809         return rc;
2810 }
2811 #endif /* CONFIG_NETLABEL */