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  *
  20  * Updated: Chad Sellers <csellers@tresys.com>
  21  *
  22  *  Added validation of kernel classes and permissions
  23  *
  24  * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
  25  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
  26  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
  27  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
  28  *      This program is free software; you can redistribute it and/or modify
  29  *      it under the terms of the GNU General Public License as published by
  30  *      the Free Software Foundation, version 2.
  31  */
  32 #include <linux/kernel.h>
  33 #include <linux/slab.h>
  34 #include <linux/string.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/rcupdate.h>
  37 #include <linux/errno.h>
  38 #include <linux/in.h>
  39 #include <linux/sched.h>
  40 #include <linux/audit.h>
  41 #include <linux/mutex.h>
  42 #include <net/netlabel.h>
  43
  44 #include "flask.h"
  45 #include "avc.h"
  46 #include "avc_ss.h"
  47 #include "security.h"
  48 #include "context.h"
  49 #include "policydb.h"
  50 #include "sidtab.h"
  51 #include "services.h"
  52 #include "conditional.h"
  53 #include "mls.h"
  54 #include "objsec.h"
  55 #include "netlabel.h"
  56 #include "xfrm.h"
  57 #include "ebitmap.h"
  58
  59 extern void selnl_notify_policyload(u32 seqno);
  60 unsigned int policydb_loaded_version;
  61
  62 /*
  63  * This is declared in avc.c
  64  */
  65 extern const struct selinux_class_perm selinux_class_perm;
  66
  67 static DEFINE_RWLOCK(policy_rwlock);
  68 #define POLICY_RDLOCK read_lock(&policy_rwlock)
  69 #define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
  70 #define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
  71 #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
  72
  73 static DEFINE_MUTEX(load_mutex);
  74 #define LOAD_LOCK mutex_lock(&load_mutex)
  75 #define LOAD_UNLOCK mutex_unlock(&load_mutex)
  76
  77 static struct sidtab sidtab;
  78 struct policydb policydb;
  79 int ss_initialized = 0;
  80
  81 /*
  82  * The largest sequence number that has been used when
  83  * providing an access decision to the access vector cache.
  84  * The sequence number only changes when a policy change
  85  * occurs.
  86  */
  87 static u32 latest_granting = 0;
  88
  89 /* Forward declaration. */
  90 static int context_struct_to_string(struct context *context, char **scontext,
  91                                     u32 *scontext_len);
  92
  93 /*
  94  * Return the boolean value of a constraint expression
  95  * when it is applied to the specified source and target
  96  * security contexts.
  97  *
  98  * xcontext is a special beast...  It is used by the validatetrans rules
  99  * only.  For these rules, scontext is the context before the transition,
 100  * tcontext is the context after the transition, and xcontext is the context
 101  * of the process performing the transition.  All other callers of
 102  * constraint_expr_eval should pass in NULL for xcontext.
 103  */
 104 static int constraint_expr_eval(struct context *scontext,
 105                                 struct context *tcontext,
 106                                 struct context *xcontext,
 107                                 struct constraint_expr *cexpr)
 108 {
 109         u32 val1, val2;
 110         struct context *c;
 111         struct role_datum *r1, *r2;
 112         struct mls_level *l1, *l2;
 113         struct constraint_expr *e;
 114         int s[CEXPR_MAXDEPTH];
 115         int sp = -1;
 116
 117         for (e = cexpr; e; e = e->next) {
 118                 switch (e->expr_type) {
 119                 case CEXPR_NOT:
 120                         BUG_ON(sp < 0);
 121                         s[sp] = !s[sp];
 122                         break;
 123                 case CEXPR_AND:
 124                         BUG_ON(sp < 1);
 125                         sp--;
 126                         s[sp] &= s[sp+1];
 127                         break;
 128                 case CEXPR_OR:
 129                         BUG_ON(sp < 1);
 130                         sp--;
 131                         s[sp] |= s[sp+1];
 132                         break;
 133                 case CEXPR_ATTR:
 134                         if (sp == (CEXPR_MAXDEPTH-1))
 135                                 return 0;
 136                         switch (e->attr) {
 137                         case CEXPR_USER:
 138                                 val1 = scontext->user;
 139                                 val2 = tcontext->user;
 140                                 break;
 141                         case CEXPR_TYPE:
 142                                 val1 = scontext->type;
 143                                 val2 = tcontext->type;
 144                                 break;
 145                         case CEXPR_ROLE:
 146                                 val1 = scontext->role;
 147                                 val2 = tcontext->role;
 148                                 r1 = policydb.role_val_to_struct[val1 - 1];
 149                                 r2 = policydb.role_val_to_struct[val2 - 1];
 150                                 switch (e->op) {
 151                                 case CEXPR_DOM:
 152                                         s[++sp] = ebitmap_get_bit(&r1->dominates,
 153                                                                   val2 - 1);
 154                                         continue;
 155                                 case CEXPR_DOMBY:
 156                                         s[++sp] = ebitmap_get_bit(&r2->dominates,
 157                                                                   val1 - 1);
 158                                         continue;
 159                                 case CEXPR_INCOMP:
 160                                         s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
 161                                                                      val2 - 1) &&
 162                                                     !ebitmap_get_bit(&r2->dominates,
 163                                                                      val1 - 1) );
 164                                         continue;
 165                                 default:
 166                                         break;
 167                                 }
 168                                 break;
 169                         case CEXPR_L1L2:
 170                                 l1 = &(scontext->range.level[0]);
 171                                 l2 = &(tcontext->range.level[0]);
 172                                 goto mls_ops;
 173                         case CEXPR_L1H2:
 174                                 l1 = &(scontext->range.level[0]);
 175                                 l2 = &(tcontext->range.level[1]);
 176                                 goto mls_ops;
 177                         case CEXPR_H1L2:
 178                                 l1 = &(scontext->range.level[1]);
 179                                 l2 = &(tcontext->range.level[0]);
 180                                 goto mls_ops;
 181                         case CEXPR_H1H2:
 182                                 l1 = &(scontext->range.level[1]);
 183                                 l2 = &(tcontext->range.level[1]);
 184                                 goto mls_ops;
 185                         case CEXPR_L1H1:
 186                                 l1 = &(scontext->range.level[0]);
 187                                 l2 = &(scontext->range.level[1]);
 188                                 goto mls_ops;
 189                         case CEXPR_L2H2:
 190                                 l1 = &(tcontext->range.level[0]);
 191                                 l2 = &(tcontext->range.level[1]);
 192                                 goto mls_ops;
 193 mls_ops:
 194                         switch (e->op) {
 195                         case CEXPR_EQ:
 196                                 s[++sp] = mls_level_eq(l1, l2);
 197                                 continue;
 198                         case CEXPR_NEQ:
 199                                 s[++sp] = !mls_level_eq(l1, l2);
 200                                 continue;
 201                         case CEXPR_DOM:
 202                                 s[++sp] = mls_level_dom(l1, l2);
 203                                 continue;
 204                         case CEXPR_DOMBY:
 205                                 s[++sp] = mls_level_dom(l2, l1);
 206                                 continue;
 207                         case CEXPR_INCOMP:
 208                                 s[++sp] = mls_level_incomp(l2, l1);
 209                                 continue;
 210                         default:
 211                                 BUG();
 212                                 return 0;
 213                         }
 214                         break;
 215                         default:
 216                                 BUG();
 217                                 return 0;
 218                         }
 219
 220                         switch (e->op) {
 221                         case CEXPR_EQ:
 222                                 s[++sp] = (val1 == val2);
 223                                 break;
 224                         case CEXPR_NEQ:
 225                                 s[++sp] = (val1 != val2);
 226                                 break;
 227                         default:
 228                                 BUG();
 229                                 return 0;
 230                         }
 231                         break;
 232                 case CEXPR_NAMES:
 233                         if (sp == (CEXPR_MAXDEPTH-1))
 234                                 return 0;
 235                         c = scontext;
 236                         if (e->attr & CEXPR_TARGET)
 237                                 c = tcontext;
 238                         else if (e->attr & CEXPR_XTARGET) {
 239                                 c = xcontext;
 240                                 if (!c) {
 241                                         BUG();
 242                                         return 0;
 243                                 }
 244                         }
 245                         if (e->attr & CEXPR_USER)
 246                                 val1 = c->user;
 247                         else if (e->attr & CEXPR_ROLE)
 248                                 val1 = c->role;
 249                         else if (e->attr & CEXPR_TYPE)
 250                                 val1 = c->type;
 251                         else {
 252                                 BUG();
 253                                 return 0;
 254                         }
 255
 256                         switch (e->op) {
 257                         case CEXPR_EQ:
 258                                 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
 259                                 break;
 260                         case CEXPR_NEQ:
 261                                 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
 262                                 break;
 263                         default:
 264                                 BUG();
 265                                 return 0;
 266                         }
 267                         break;
 268                 default:
 269                         BUG();
 270                         return 0;
 271                 }
 272         }
 273
 274         BUG_ON(sp != 0);
 275         return s[0];
 276 }
 277
 278 /*
 279  * Compute access vectors based on a context structure pair for
 280  * the permissions in a particular class.
 281  */
 282 static int context_struct_compute_av(struct context *scontext,
 283                                      struct context *tcontext,
 284                                      u16 tclass,
 285                                      u32 requested,
 286                                      struct av_decision *avd)
 287 {
 288         struct constraint_node *constraint;
 289         struct role_allow *ra;
 290         struct avtab_key avkey;
 291         struct avtab_node *node;
 292         struct class_datum *tclass_datum;
 293         struct ebitmap *sattr, *tattr;
 294         struct ebitmap_node *snode, *tnode;
 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         if (!tclass || tclass > policydb.p_classes.nprim) {
 309                 printk(KERN_ERR "security_compute_av:  unrecognized class %d\n",
 310                        tclass);
 311                 return -EINVAL;
 312         }
 313         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 314
 315         /*
 316          * Initialize the access vectors to the default values.
 317          */
 318         avd->allowed = 0;
 319         avd->decided = 0xffffffff;
 320         avd->auditallow = 0;
 321         avd->auditdeny = 0xffffffff;
 322         avd->seqno = latest_granting;
 323
 324         /*
 325          * If a specific type enforcement rule was defined for
 326          * this permission check, then use it.
 327          */
 328         avkey.target_class = tclass;
 329         avkey.specified = AVTAB_AV;
 330         sattr = &policydb.type_attr_map[scontext->type - 1];
 331         tattr = &policydb.type_attr_map[tcontext->type - 1];
 332         ebitmap_for_each_bit(sattr, snode, i) {
 333                 if (!ebitmap_node_get_bit(snode, i))
 334                         continue;
 335                 ebitmap_for_each_bit(tattr, tnode, j) {
 336                         if (!ebitmap_node_get_bit(tnode, j))
 337                                 continue;
 338                         avkey.source_type = i + 1;
 339                         avkey.target_type = j + 1;
 340                         for (node = avtab_search_node(&policydb.te_avtab, &avkey);
 341                              node != NULL;
 342                              node = avtab_search_node_next(node, avkey.specified)) {
 343                                 if (node->key.specified == AVTAB_ALLOWED)
 344                                         avd->allowed |= node->datum.data;
 345                                 else if (node->key.specified == AVTAB_AUDITALLOW)
 346                                         avd->auditallow |= node->datum.data;
 347                                 else if (node->key.specified == AVTAB_AUDITDENY)
 348                                         avd->auditdeny &= node->datum.data;
 349                         }
 350
 351                         /* Check conditional av table for additional permissions */
 352                         cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
 353
 354                 }
 355         }
 356
 357         /*
 358          * Remove any permissions prohibited by a constraint (this includes
 359          * the MLS policy).
 360          */
 361         constraint = tclass_datum->constraints;
 362         while (constraint) {
 363                 if ((constraint->permissions & (avd->allowed)) &&
 364                     !constraint_expr_eval(scontext, tcontext, NULL,
 365                                           constraint->expr)) {
 366                         avd->allowed = (avd->allowed) & ~(constraint->permissions);
 367                 }
 368                 constraint = constraint->next;
 369         }
 370
 371         /*
 372          * If checking process transition permission and the
 373          * role is changing, then check the (current_role, new_role)
 374          * pair.
 375          */
 376         if (tclass == SECCLASS_PROCESS &&
 377             (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
 378             scontext->role != tcontext->role) {
 379                 for (ra = policydb.role_allow; ra; ra = ra->next) {
 380                         if (scontext->role == ra->role &&
 381                             tcontext->role == ra->new_role)
 382                                 break;
 383                 }
 384                 if (!ra)
 385                         avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
 386                                                         PROCESS__DYNTRANSITION);
 387         }
 388
 389         return 0;
 390 }
 391
 392 static int security_validtrans_handle_fail(struct context *ocontext,
 393                                            struct context *ncontext,
 394                                            struct context *tcontext,
 395                                            u16 tclass)
 396 {
 397         char *o = NULL, *n = NULL, *t = NULL;
 398         u32 olen, nlen, tlen;
 399
 400         if (context_struct_to_string(ocontext, &o, &olen) < 0)
 401                 goto out;
 402         if (context_struct_to_string(ncontext, &n, &nlen) < 0)
 403                 goto out;
 404         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 405                 goto out;
 406         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 407                   "security_validate_transition:  denied for"
 408                   " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
 409                   o, n, t, policydb.p_class_val_to_name[tclass-1]);
 410 out:
 411         kfree(o);
 412         kfree(n);
 413         kfree(t);
 414
 415         if (!selinux_enforcing)
 416                 return 0;
 417         return -EPERM;
 418 }
 419
 420 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
 421                                  u16 tclass)
 422 {
 423         struct context *ocontext;
 424         struct context *ncontext;
 425         struct context *tcontext;
 426         struct class_datum *tclass_datum;
 427         struct constraint_node *constraint;
 428         int rc = 0;
 429
 430         if (!ss_initialized)
 431                 return 0;
 432
 433         POLICY_RDLOCK;
 434
 435         /*
 436          * Remap extended Netlink classes for old policy versions.
 437          * Do this here rather than socket_type_to_security_class()
 438          * in case a newer policy version is loaded, allowing sockets
 439          * to remain in the correct class.
 440          */
 441         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 442                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 443                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 444                         tclass = SECCLASS_NETLINK_SOCKET;
 445
 446         if (!tclass || tclass > policydb.p_classes.nprim) {
 447                 printk(KERN_ERR "security_validate_transition:  "
 448                        "unrecognized class %d\n", tclass);
 449                 rc = -EINVAL;
 450                 goto out;
 451         }
 452         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 453
 454         ocontext = sidtab_search(&sidtab, oldsid);
 455         if (!ocontext) {
 456                 printk(KERN_ERR "security_validate_transition: "
 457                        " unrecognized SID %d\n", oldsid);
 458                 rc = -EINVAL;
 459                 goto out;
 460         }
 461
 462         ncontext = sidtab_search(&sidtab, newsid);
 463         if (!ncontext) {
 464                 printk(KERN_ERR "security_validate_transition: "
 465                        " unrecognized SID %d\n", newsid);
 466                 rc = -EINVAL;
 467                 goto out;
 468         }
 469
 470         tcontext = sidtab_search(&sidtab, tasksid);
 471         if (!tcontext) {
 472                 printk(KERN_ERR "security_validate_transition: "
 473                        " unrecognized SID %d\n", tasksid);
 474                 rc = -EINVAL;
 475                 goto out;
 476         }
 477
 478         constraint = tclass_datum->validatetrans;
 479         while (constraint) {
 480                 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
 481                                           constraint->expr)) {
 482                         rc = security_validtrans_handle_fail(ocontext, ncontext,
 483                                                              tcontext, tclass);
 484                         goto out;
 485                 }
 486                 constraint = constraint->next;
 487         }
 488
 489 out:
 490         POLICY_RDUNLOCK;
 491         return rc;
 492 }
 493
 494 /**
 495  * security_compute_av - Compute access vector decisions.
 496  * @ssid: source security identifier
 497  * @tsid: target security identifier
 498  * @tclass: target security class
 499  * @requested: requested permissions
 500  * @avd: access vector decisions
 501  *
 502  * Compute a set of access vector decisions based on the
 503  * SID pair (@ssid, @tsid) for the permissions in @tclass.
 504  * Return -%EINVAL if any of the parameters are invalid or %0
 505  * if the access vector decisions were computed successfully.
 506  */
 507 int security_compute_av(u32 ssid,
 508                         u32 tsid,
 509                         u16 tclass,
 510                         u32 requested,
 511                         struct av_decision *avd)
 512 {
 513         struct context *scontext = NULL, *tcontext = NULL;
 514         int rc = 0;
 515
 516         if (!ss_initialized) {
 517                 avd->allowed = 0xffffffff;
 518                 avd->decided = 0xffffffff;
 519                 avd->auditallow = 0;
 520                 avd->auditdeny = 0xffffffff;
 521                 avd->seqno = latest_granting;
 522                 return 0;
 523         }
 524
 525         POLICY_RDLOCK;
 526
 527         scontext = sidtab_search(&sidtab, ssid);
 528         if (!scontext) {
 529                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
 530                        ssid);
 531                 rc = -EINVAL;
 532                 goto out;
 533         }
 534         tcontext = sidtab_search(&sidtab, tsid);
 535         if (!tcontext) {
 536                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
 537                        tsid);
 538                 rc = -EINVAL;
 539                 goto out;
 540         }
 541
 542         rc = context_struct_compute_av(scontext, tcontext, tclass,
 543                                        requested, avd);
 544 out:
 545         POLICY_RDUNLOCK;
 546         return rc;
 547 }
 548
 549 /*
 550  * Write the security context string representation of
 551  * the context structure `context' into a dynamically
 552  * allocated string of the correct size.  Set `*scontext'
 553  * to point to this string and set `*scontext_len' to
 554  * the length of the string.
 555  */
 556 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
 557 {
 558         char *scontextp;
 559
 560         *scontext = NULL;
 561         *scontext_len = 0;
 562
 563         /* Compute the size of the context. */
 564         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
 565         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
 566         *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
 567         *scontext_len += mls_compute_context_len(context);
 568
 569         /* Allocate space for the context; caller must free this space. */
 570         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 571         if (!scontextp) {
 572                 return -ENOMEM;
 573         }
 574         *scontext = scontextp;
 575
 576         /*
 577          * Copy the user name, role name and type name into the context.
 578          */
 579         sprintf(scontextp, "%s:%s:%s",
 580                 policydb.p_user_val_to_name[context->user - 1],
 581                 policydb.p_role_val_to_name[context->role - 1],
 582                 policydb.p_type_val_to_name[context->type - 1]);
 583         scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
 584                      1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
 585                      1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
 586
 587         mls_sid_to_context(context, &scontextp);
 588
 589         *scontextp = 0;
 590
 591         return 0;
 592 }
 593
 594 #include "initial_sid_to_string.h"
 595
 596 /**
 597  * security_sid_to_context - Obtain a context for a given SID.
 598  * @sid: security identifier, SID
 599  * @scontext: security context
 600  * @scontext_len: length in bytes
 601  *
 602  * Write the string representation of the context associated with @sid
 603  * into a dynamically allocated string of the correct size.  Set @scontext
 604  * to point to this string and set @scontext_len to the length of the string.
 605  */
 606 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
 607 {
 608         struct context *context;
 609         int rc = 0;
 610
 611         *scontext = NULL;
 612         *scontext_len  = 0;
 613
 614         if (!ss_initialized) {
 615                 if (sid <= SECINITSID_NUM) {
 616                         char *scontextp;
 617
 618                         *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
 619                         scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
 620                         if (!scontextp) {
 621                                 rc = -ENOMEM;
 622                                 goto out;
 623                         }
 624                         strcpy(scontextp, initial_sid_to_string[sid]);
 625                         *scontext = scontextp;
 626                         goto out;
 627                 }
 628                 printk(KERN_ERR "security_sid_to_context:  called before initial "
 629                        "load_policy on unknown SID %d\n", sid);
 630                 rc = -EINVAL;
 631                 goto out;
 632         }
 633         POLICY_RDLOCK;
 634         context = sidtab_search(&sidtab, sid);
 635         if (!context) {
 636                 printk(KERN_ERR "security_sid_to_context:  unrecognized SID "
 637                        "%d\n", sid);
 638                 rc = -EINVAL;
 639                 goto out_unlock;
 640         }
 641         rc = context_struct_to_string(context, scontext, scontext_len);
 642 out_unlock:
 643         POLICY_RDUNLOCK;
 644 out:
 645         return rc;
 646
 647 }
 648
 649 static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
 650 {
 651         char *scontext2;
 652         struct context context;
 653         struct role_datum *role;
 654         struct type_datum *typdatum;
 655         struct user_datum *usrdatum;
 656         char *scontextp, *p, oldc;
 657         int rc = 0;
 658
 659         if (!ss_initialized) {
 660                 int i;
 661
 662                 for (i = 1; i < SECINITSID_NUM; i++) {
 663                         if (!strcmp(initial_sid_to_string[i], scontext)) {
 664                                 *sid = i;
 665                                 goto out;
 666                         }
 667                 }
 668                 *sid = SECINITSID_KERNEL;
 669                 goto out;
 670         }
 671         *sid = SECSID_NULL;
 672
 673         /* Copy the string so that we can modify the copy as we parse it.
 674            The string should already by null terminated, but we append a
 675            null suffix to the copy to avoid problems with the existing
 676            attr package, which doesn't view the null terminator as part
 677            of the attribute value. */
 678         scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
 679         if (!scontext2) {
 680                 rc = -ENOMEM;
 681                 goto out;
 682         }
 683         memcpy(scontext2, scontext, scontext_len);
 684         scontext2[scontext_len] = 0;
 685
 686         context_init(&context);
 687         *sid = SECSID_NULL;
 688
 689         POLICY_RDLOCK;
 690
 691         /* Parse the security context. */
 692
 693         rc = -EINVAL;
 694         scontextp = (char *) scontext2;
 695
 696         /* Extract the user. */
 697         p = scontextp;
 698         while (*p && *p != ':')
 699                 p++;
 700
 701         if (*p == 0)
 702                 goto out_unlock;
 703
 704         *p++ = 0;
 705
 706         usrdatum = hashtab_search(policydb.p_users.table, scontextp);
 707         if (!usrdatum)
 708                 goto out_unlock;
 709
 710         context.user = usrdatum->value;
 711
 712         /* Extract role. */
 713         scontextp = p;
 714         while (*p && *p != ':')
 715                 p++;
 716
 717         if (*p == 0)
 718                 goto out_unlock;
 719
 720         *p++ = 0;
 721
 722         role = hashtab_search(policydb.p_roles.table, scontextp);
 723         if (!role)
 724                 goto out_unlock;
 725         context.role = role->value;
 726
 727         /* Extract type. */
 728         scontextp = p;
 729         while (*p && *p != ':')
 730                 p++;
 731         oldc = *p;
 732         *p++ = 0;
 733
 734         typdatum = hashtab_search(policydb.p_types.table, scontextp);
 735         if (!typdatum)
 736                 goto out_unlock;
 737
 738         context.type = typdatum->value;
 739
 740         rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
 741         if (rc)
 742                 goto out_unlock;
 743
 744         if ((p - scontext2) < scontext_len) {
 745                 rc = -EINVAL;
 746                 goto out_unlock;
 747         }
 748
 749         /* Check the validity of the new context. */
 750         if (!policydb_context_isvalid(&policydb, &context)) {
 751                 rc = -EINVAL;
 752                 goto out_unlock;
 753         }
 754         /* Obtain the new sid. */
 755         rc = sidtab_context_to_sid(&sidtab, &context, sid);
 756 out_unlock:
 757         POLICY_RDUNLOCK;
 758         context_destroy(&context);
 759         kfree(scontext2);
 760 out:
 761         return rc;
 762 }
 763
 764 /**
 765  * security_context_to_sid - Obtain a SID for a given security context.
 766  * @scontext: security context
 767  * @scontext_len: length in bytes
 768  * @sid: security identifier, SID
 769  *
 770  * Obtains a SID associated with the security context that
 771  * has the string representation specified by @scontext.
 772  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 773  * memory is available, or 0 on success.
 774  */
 775 int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
 776 {
 777         return security_context_to_sid_core(scontext, scontext_len,
 778                                             sid, SECSID_NULL);
 779 }
 780
 781 /**
 782  * security_context_to_sid_default - Obtain a SID for a given security context,
 783  * falling back to specified default if needed.
 784  *
 785  * @scontext: security context
 786  * @scontext_len: length in bytes
 787  * @sid: security identifier, SID
 788  * @def_sid: default SID to assign on errror
 789  *
 790  * Obtains a SID associated with the security context that
 791  * has the string representation specified by @scontext.
 792  * The default SID is passed to the MLS layer to be used to allow
 793  * kernel labeling of the MLS field if the MLS field is not present
 794  * (for upgrading to MLS without full relabel).
 795  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 796  * memory is available, or 0 on success.
 797  */
 798 int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
 799 {
 800         return security_context_to_sid_core(scontext, scontext_len,
 801                                             sid, def_sid);
 802 }
 803
 804 static int compute_sid_handle_invalid_context(
 805         struct context *scontext,
 806         struct context *tcontext,
 807         u16 tclass,
 808         struct context *newcontext)
 809 {
 810         char *s = NULL, *t = NULL, *n = NULL;
 811         u32 slen, tlen, nlen;
 812
 813         if (context_struct_to_string(scontext, &s, &slen) < 0)
 814                 goto out;
 815         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 816                 goto out;
 817         if (context_struct_to_string(newcontext, &n, &nlen) < 0)
 818                 goto out;
 819         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 820                   "security_compute_sid:  invalid context %s"
 821                   " for scontext=%s"
 822                   " tcontext=%s"
 823                   " tclass=%s",
 824                   n, s, t, policydb.p_class_val_to_name[tclass-1]);
 825 out:
 826         kfree(s);
 827         kfree(t);
 828         kfree(n);
 829         if (!selinux_enforcing)
 830                 return 0;
 831         return -EACCES;
 832 }
 833
 834 static int security_compute_sid(u32 ssid,
 835                                 u32 tsid,
 836                                 u16 tclass,
 837                                 u32 specified,
 838                                 u32 *out_sid)
 839 {
 840         struct context *scontext = NULL, *tcontext = NULL, newcontext;
 841         struct role_trans *roletr = NULL;
 842         struct avtab_key avkey;
 843         struct avtab_datum *avdatum;
 844         struct avtab_node *node;
 845         int rc = 0;
 846
 847         if (!ss_initialized) {
 848                 switch (tclass) {
 849                 case SECCLASS_PROCESS:
 850                         *out_sid = ssid;
 851                         break;
 852                 default:
 853                         *out_sid = tsid;
 854                         break;
 855                 }
 856                 goto out;
 857         }
 858
 859         context_init(&newcontext);
 860
 861         POLICY_RDLOCK;
 862
 863         scontext = sidtab_search(&sidtab, ssid);
 864         if (!scontext) {
 865                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
 866                        ssid);
 867                 rc = -EINVAL;
 868                 goto out_unlock;
 869         }
 870         tcontext = sidtab_search(&sidtab, tsid);
 871         if (!tcontext) {
 872                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
 873                        tsid);
 874                 rc = -EINVAL;
 875                 goto out_unlock;
 876         }
 877
 878         /* Set the user identity. */
 879         switch (specified) {
 880         case AVTAB_TRANSITION:
 881         case AVTAB_CHANGE:
 882                 /* Use the process user identity. */
 883                 newcontext.user = scontext->user;
 884                 break;
 885         case AVTAB_MEMBER:
 886                 /* Use the related object owner. */
 887                 newcontext.user = tcontext->user;
 888                 break;
 889         }
 890
 891         /* Set the role and type to default values. */
 892         switch (tclass) {
 893         case SECCLASS_PROCESS:
 894                 /* Use the current role and type of process. */
 895                 newcontext.role = scontext->role;
 896                 newcontext.type = scontext->type;
 897                 break;
 898         default:
 899                 /* Use the well-defined object role. */
 900                 newcontext.role = OBJECT_R_VAL;
 901                 /* Use the type of the related object. */
 902                 newcontext.type = tcontext->type;
 903         }
 904
 905         /* Look for a type transition/member/change rule. */
 906         avkey.source_type = scontext->type;
 907         avkey.target_type = tcontext->type;
 908         avkey.target_class = tclass;
 909         avkey.specified = specified;
 910         avdatum = avtab_search(&policydb.te_avtab, &avkey);
 911
 912         /* If no permanent rule, also check for enabled conditional rules */
 913         if(!avdatum) {
 914                 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
 915                 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
 916                         if (node->key.specified & AVTAB_ENABLED) {
 917                                 avdatum = &node->datum;
 918                                 break;
 919                         }
 920                 }
 921         }
 922
 923         if (avdatum) {
 924                 /* Use the type from the type transition/member/change rule. */
 925                 newcontext.type = avdatum->data;
 926         }
 927
 928         /* Check for class-specific changes. */
 929         switch (tclass) {
 930         case SECCLASS_PROCESS:
 931                 if (specified & AVTAB_TRANSITION) {
 932                         /* Look for a role transition rule. */
 933                         for (roletr = policydb.role_tr; roletr;
 934                              roletr = roletr->next) {
 935                                 if (roletr->role == scontext->role &&
 936                                     roletr->type == tcontext->type) {
 937                                         /* Use the role transition rule. */
 938                                         newcontext.role = roletr->new_role;
 939                                         break;
 940                                 }
 941                         }
 942                 }
 943                 break;
 944         default:
 945                 break;
 946         }
 947
 948         /* Set the MLS attributes.
 949            This is done last because it may allocate memory. */
 950         rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
 951         if (rc)
 952                 goto out_unlock;
 953
 954         /* Check the validity of the context. */
 955         if (!policydb_context_isvalid(&policydb, &newcontext)) {
 956                 rc = compute_sid_handle_invalid_context(scontext,
 957                                                         tcontext,
 958                                                         tclass,
 959                                                         &newcontext);
 960                 if (rc)
 961                         goto out_unlock;
 962         }
 963         /* Obtain the sid for the context. */
 964         rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
 965 out_unlock:
 966         POLICY_RDUNLOCK;
 967         context_destroy(&newcontext);
 968 out:
 969         return rc;
 970 }
 971
 972 /**
 973  * security_transition_sid - Compute the SID for a new subject/object.
 974  * @ssid: source security identifier
 975  * @tsid: target security identifier
 976  * @tclass: target security class
 977  * @out_sid: security identifier for new subject/object
 978  *
 979  * Compute a SID to use for labeling a new subject or object in the
 980  * class @tclass based on a SID pair (@ssid, @tsid).
 981  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
 982  * if insufficient memory is available, or %0 if the new SID was
 983  * computed successfully.
 984  */
 985 int security_transition_sid(u32 ssid,
 986                             u32 tsid,
 987                             u16 tclass,
 988                             u32 *out_sid)
 989 {
 990         return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
 991 }
 992
 993 /**
 994  * security_member_sid - Compute the SID for member selection.
 995  * @ssid: source security identifier
 996  * @tsid: target security identifier
 997  * @tclass: target security class
 998  * @out_sid: security identifier for selected member
 999  *
1000  * Compute a SID to use when selecting a member of a polyinstantiated
1001  * object of class @tclass based on a SID pair (@ssid, @tsid).
1002  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1003  * if insufficient memory is available, or %0 if the SID was
1004  * computed successfully.
1005  */
1006 int security_member_sid(u32 ssid,
1007                         u32 tsid,
1008                         u16 tclass,
1009                         u32 *out_sid)
1010 {
1011         return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
1012 }
1013
1014 /**
1015  * security_change_sid - Compute the SID for object relabeling.
1016  * @ssid: source security identifier
1017  * @tsid: target security identifier
1018  * @tclass: target security class
1019  * @out_sid: security identifier for selected member
1020  *
1021  * Compute a SID to use for relabeling an object of class @tclass
1022  * based on a SID pair (@ssid, @tsid).
1023  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1024  * if insufficient memory is available, or %0 if the SID was
1025  * computed successfully.
1026  */
1027 int security_change_sid(u32 ssid,
1028                         u32 tsid,
1029                         u16 tclass,
1030                         u32 *out_sid)
1031 {
1032         return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1033 }
1034
1035 /*
1036  * Verify that each kernel class that is defined in the
1037  * policy is correct
1038  */
1039 static int validate_classes(struct policydb *p)
1040 {
1041         int i, j;
1042         struct class_datum *cladatum;
1043         struct perm_datum *perdatum;
1044         u32 nprim, tmp, common_pts_len, perm_val, pol_val;
1045         u16 class_val;
1046         const struct selinux_class_perm *kdefs = &selinux_class_perm;
1047         const char *def_class, *def_perm, *pol_class;
1048         struct symtab *perms;
1049
1050         for (i = 1; i < kdefs->cts_len; i++) {
1051                 def_class = kdefs->class_to_string[i];
1052                 if (!def_class)
1053                         continue;
1054                 if (i > p->p_classes.nprim) {
1055                         printk(KERN_INFO
1056                                "security:  class %s not defined in policy\n",
1057                                def_class);
1058                         continue;
1059                 }
1060                 pol_class = p->p_class_val_to_name[i-1];
1061                 if (strcmp(pol_class, def_class)) {
1062                         printk(KERN_ERR
1063                                "security:  class %d is incorrect, found %s but should be %s\n",
1064                                i, pol_class, def_class);
1065                         return -EINVAL;
1066                 }
1067         }
1068         for (i = 0; i < kdefs->av_pts_len; i++) {
1069                 class_val = kdefs->av_perm_to_string[i].tclass;
1070                 perm_val = kdefs->av_perm_to_string[i].value;
1071                 def_perm = kdefs->av_perm_to_string[i].name;
1072                 if (class_val > p->p_classes.nprim)
1073                         continue;
1074                 pol_class = p->p_class_val_to_name[class_val-1];
1075                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1076                 BUG_ON(!cladatum);
1077                 perms = &cladatum->permissions;
1078                 nprim = 1 << (perms->nprim - 1);
1079                 if (perm_val > nprim) {
1080                         printk(KERN_INFO
1081                                "security:  permission %s in class %s not defined in policy\n",
1082                                def_perm, pol_class);
1083                         continue;
1084                 }
1085                 perdatum = hashtab_search(perms->table, def_perm);
1086                 if (perdatum == NULL) {
1087                         printk(KERN_ERR
1088                                "security:  permission %s in class %s not found in policy\n",
1089                                def_perm, pol_class);
1090                         return -EINVAL;
1091                 }
1092                 pol_val = 1 << (perdatum->value - 1);
1093                 if (pol_val != perm_val) {
1094                         printk(KERN_ERR
1095                                "security:  permission %s in class %s has incorrect value\n",
1096                                def_perm, pol_class);
1097                         return -EINVAL;
1098                 }
1099         }
1100         for (i = 0; i < kdefs->av_inherit_len; i++) {
1101                 class_val = kdefs->av_inherit[i].tclass;
1102                 if (class_val > p->p_classes.nprim)
1103                         continue;
1104                 pol_class = p->p_class_val_to_name[class_val-1];
1105                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1106                 BUG_ON(!cladatum);
1107                 if (!cladatum->comdatum) {
1108                         printk(KERN_ERR
1109                                "security:  class %s should have an inherits clause but does not\n",
1110                                pol_class);
1111                         return -EINVAL;
1112                 }
1113                 tmp = kdefs->av_inherit[i].common_base;
1114                 common_pts_len = 0;
1115                 while (!(tmp & 0x01)) {
1116                         common_pts_len++;
1117                         tmp >>= 1;
1118                 }
1119                 perms = &cladatum->comdatum->permissions;
1120                 for (j = 0; j < common_pts_len; j++) {
1121                         def_perm = kdefs->av_inherit[i].common_pts[j];
1122                         if (j >= perms->nprim) {
1123                                 printk(KERN_INFO
1124                                        "security:  permission %s in class %s not defined in policy\n",
1125                                        def_perm, pol_class);
1126                                 continue;
1127                         }
1128                         perdatum = hashtab_search(perms->table, def_perm);
1129                         if (perdatum == NULL) {
1130                                 printk(KERN_ERR
1131                                        "security:  permission %s in class %s not found in policy\n",
1132                                        def_perm, pol_class);
1133                                 return -EINVAL;
1134                         }
1135                         if (perdatum->value != j + 1) {
1136                                 printk(KERN_ERR
1137                                        "security:  permission %s in class %s has incorrect value\n",
1138                                        def_perm, pol_class);
1139                                 return -EINVAL;
1140                         }
1141                 }
1142         }
1143         return 0;
1144 }
1145
1146 /* Clone the SID into the new SID table. */
1147 static int clone_sid(u32 sid,
1148                      struct context *context,
1149                      void *arg)
1150 {
1151         struct sidtab *s = arg;
1152
1153         return sidtab_insert(s, sid, context);
1154 }
1155
1156 static inline int convert_context_handle_invalid_context(struct context *context)
1157 {
1158         int rc = 0;
1159
1160         if (selinux_enforcing) {
1161                 rc = -EINVAL;
1162         } else {
1163                 char *s;
1164                 u32 len;
1165
1166                 context_struct_to_string(context, &s, &len);
1167                 printk(KERN_ERR "security:  context %s is invalid\n", s);
1168                 kfree(s);
1169         }
1170         return rc;
1171 }
1172
1173 struct convert_context_args {
1174         struct policydb *oldp;
1175         struct policydb *newp;
1176 };
1177
1178 /*
1179  * Convert the values in the security context
1180  * structure `c' from the values specified
1181  * in the policy `p->oldp' to the values specified
1182  * in the policy `p->newp'.  Verify that the
1183  * context is valid under the new policy.
1184  */
1185 static int convert_context(u32 key,
1186                            struct context *c,
1187                            void *p)
1188 {
1189         struct convert_context_args *args;
1190         struct context oldc;
1191         struct role_datum *role;
1192         struct type_datum *typdatum;
1193         struct user_datum *usrdatum;
1194         char *s;
1195         u32 len;
1196         int rc;
1197
1198         args = p;
1199
1200         rc = context_cpy(&oldc, c);
1201         if (rc)
1202                 goto out;
1203
1204         rc = -EINVAL;
1205
1206         /* Convert the user. */
1207         usrdatum = hashtab_search(args->newp->p_users.table,
1208                                   args->oldp->p_user_val_to_name[c->user - 1]);
1209         if (!usrdatum) {
1210                 goto bad;
1211         }
1212         c->user = usrdatum->value;
1213
1214         /* Convert the role. */
1215         role = hashtab_search(args->newp->p_roles.table,
1216                               args->oldp->p_role_val_to_name[c->role - 1]);
1217         if (!role) {
1218                 goto bad;
1219         }
1220         c->role = role->value;
1221
1222         /* Convert the type. */
1223         typdatum = hashtab_search(args->newp->p_types.table,
1224                                   args->oldp->p_type_val_to_name[c->type - 1]);
1225         if (!typdatum) {
1226                 goto bad;
1227         }
1228         c->type = typdatum->value;
1229
1230         rc = mls_convert_context(args->oldp, args->newp, c);
1231         if (rc)
1232                 goto bad;
1233
1234         /* Check the validity of the new context. */
1235         if (!policydb_context_isvalid(args->newp, c)) {
1236                 rc = convert_context_handle_invalid_context(&oldc);
1237                 if (rc)
1238                         goto bad;
1239         }
1240
1241         context_destroy(&oldc);
1242 out:
1243         return rc;
1244 bad:
1245         context_struct_to_string(&oldc, &s, &len);
1246         context_destroy(&oldc);
1247         printk(KERN_ERR "security:  invalidating context %s\n", s);
1248         kfree(s);
1249         goto out;
1250 }
1251
1252 extern void selinux_complete_init(void);
1253
1254 /**
1255  * security_load_policy - Load a security policy configuration.
1256  * @data: binary policy data
1257  * @len: length of data in bytes
1258  *
1259  * Load a new set of security policy configuration data,
1260  * validate it and convert the SID table as necessary.
1261  * This function will flush the access vector cache after
1262  * loading the new policy.
1263  */
1264 int security_load_policy(void *data, size_t len)
1265 {
1266         struct policydb oldpolicydb, newpolicydb;
1267         struct sidtab oldsidtab, newsidtab;
1268         struct convert_context_args args;
1269         u32 seqno;
1270         int rc = 0;
1271         struct policy_file file = { data, len }, *fp = &file;
1272
1273         LOAD_LOCK;
1274
1275         if (!ss_initialized) {
1276                 avtab_cache_init();
1277                 if (policydb_read(&policydb, fp)) {
1278                         LOAD_UNLOCK;
1279                         avtab_cache_destroy();
1280                         return -EINVAL;
1281                 }
1282                 if (policydb_load_isids(&policydb, &sidtab)) {
1283                         LOAD_UNLOCK;
1284                         policydb_destroy(&policydb);
1285                         avtab_cache_destroy();
1286                         return -EINVAL;
1287                 }
1288                 /* Verify that the kernel defined classes are correct. */
1289                 if (validate_classes(&policydb)) {
1290                         printk(KERN_ERR
1291                                "security:  the definition of a class is incorrect\n");
1292                         LOAD_UNLOCK;
1293                         sidtab_destroy(&sidtab);
1294                         policydb_destroy(&policydb);
1295                         avtab_cache_destroy();
1296                         return -EINVAL;
1297                 }
1298                 policydb_loaded_version = policydb.policyvers;
1299                 ss_initialized = 1;
1300                 seqno = ++latest_granting;
1301                 LOAD_UNLOCK;
1302                 selinux_complete_init();
1303                 avc_ss_reset(seqno);
1304                 selnl_notify_policyload(seqno);
1305                 selinux_netlbl_cache_invalidate();
1306                 selinux_xfrm_notify_policyload();
1307                 return 0;
1308         }
1309
1310 #if 0
1311         sidtab_hash_eval(&sidtab, "sids");
1312 #endif
1313
1314         if (policydb_read(&newpolicydb, fp)) {
1315                 LOAD_UNLOCK;
1316                 return -EINVAL;
1317         }
1318
1319         sidtab_init(&newsidtab);
1320
1321         /* Verify that the kernel defined classes are correct. */
1322         if (validate_classes(&newpolicydb)) {
1323                 printk(KERN_ERR
1324                        "security:  the definition of a class is incorrect\n");
1325                 rc = -EINVAL;
1326                 goto err;
1327         }
1328
1329         /* Clone the SID table. */
1330         sidtab_shutdown(&sidtab);
1331         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1332                 rc = -ENOMEM;
1333                 goto err;
1334         }
1335
1336         /* Convert the internal representations of contexts
1337            in the new SID table and remove invalid SIDs. */
1338         args.oldp = &policydb;
1339         args.newp = &newpolicydb;
1340         sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1341
1342         /* Save the old policydb and SID table to free later. */
1343         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1344         sidtab_set(&oldsidtab, &sidtab);
1345
1346         /* Install the new policydb and SID table. */
1347         POLICY_WRLOCK;
1348         memcpy(&policydb, &newpolicydb, sizeof policydb);
1349         sidtab_set(&sidtab, &newsidtab);
1350         seqno = ++latest_granting;
1351         policydb_loaded_version = policydb.policyvers;
1352         POLICY_WRUNLOCK;
1353         LOAD_UNLOCK;
1354
1355         /* Free the old policydb and SID table. */
1356         policydb_destroy(&oldpolicydb);
1357         sidtab_destroy(&oldsidtab);
1358
1359         avc_ss_reset(seqno);
1360         selnl_notify_policyload(seqno);
1361         selinux_netlbl_cache_invalidate();
1362         selinux_xfrm_notify_policyload();
1363
1364         return 0;
1365
1366 err:
1367         LOAD_UNLOCK;
1368         sidtab_destroy(&newsidtab);
1369         policydb_destroy(&newpolicydb);
1370         return rc;
1371
1372 }
1373
1374 /**
1375  * security_port_sid - Obtain the SID for a port.
1376  * @domain: communication domain aka address family
1377  * @type: socket type
1378  * @protocol: protocol number
1379  * @port: port number
1380  * @out_sid: security identifier
1381  */
1382 int security_port_sid(u16 domain,
1383                       u16 type,
1384                       u8 protocol,
1385                       u16 port,
1386                       u32 *out_sid)
1387 {
1388         struct ocontext *c;
1389         int rc = 0;
1390
1391         POLICY_RDLOCK;
1392
1393         c = policydb.ocontexts[OCON_PORT];
1394         while (c) {
1395                 if (c->u.port.protocol == protocol &&
1396                     c->u.port.low_port <= port &&
1397                     c->u.port.high_port >= port)
1398                         break;
1399                 c = c->next;
1400         }
1401
1402         if (c) {
1403                 if (!c->sid[0]) {
1404                         rc = sidtab_context_to_sid(&sidtab,
1405                                                    &c->context[0],
1406                                                    &c->sid[0]);
1407                         if (rc)
1408                                 goto out;
1409                 }
1410                 *out_sid = c->sid[0];
1411         } else {
1412                 *out_sid = SECINITSID_PORT;
1413         }
1414
1415 out:
1416         POLICY_RDUNLOCK;
1417         return rc;
1418 }
1419
1420 /**
1421  * security_netif_sid - Obtain the SID for a network interface.
1422  * @name: interface name
1423  * @if_sid: interface SID
1424  * @msg_sid: default SID for received packets
1425  */
1426 int security_netif_sid(char *name,
1427                        u32 *if_sid,
1428                        u32 *msg_sid)
1429 {
1430         int rc = 0;
1431         struct ocontext *c;
1432
1433         POLICY_RDLOCK;
1434
1435         c = policydb.ocontexts[OCON_NETIF];
1436         while (c) {
1437                 if (strcmp(name, c->u.name) == 0)
1438                         break;
1439                 c = c->next;
1440         }
1441
1442         if (c) {
1443                 if (!c->sid[0] || !c->sid[1]) {
1444                         rc = sidtab_context_to_sid(&sidtab,
1445                                                   &c->context[0],
1446                                                   &c->sid[0]);
1447                         if (rc)
1448                                 goto out;
1449                         rc = sidtab_context_to_sid(&sidtab,
1450                                                    &c->context[1],
1451                                                    &c->sid[1]);
1452                         if (rc)
1453                                 goto out;
1454                 }
1455                 *if_sid = c->sid[0];
1456                 *msg_sid = c->sid[1];
1457         } else {
1458                 *if_sid = SECINITSID_NETIF;
1459                 *msg_sid = SECINITSID_NETMSG;
1460         }
1461
1462 out:
1463         POLICY_RDUNLOCK;
1464         return rc;
1465 }
1466
1467 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1468 {
1469         int i, fail = 0;
1470
1471         for(i = 0; i < 4; i++)
1472                 if(addr[i] != (input[i] & mask[i])) {
1473                         fail = 1;
1474                         break;
1475                 }
1476
1477         return !fail;
1478 }
1479
1480 /**
1481  * security_node_sid - Obtain the SID for a node (host).
1482  * @domain: communication domain aka address family
1483  * @addrp: address
1484  * @addrlen: address length in bytes
1485  * @out_sid: security identifier
1486  */
1487 int security_node_sid(u16 domain,
1488                       void *addrp,
1489                       u32 addrlen,
1490                       u32 *out_sid)
1491 {
1492         int rc = 0;
1493         struct ocontext *c;
1494
1495         POLICY_RDLOCK;
1496
1497         switch (domain) {
1498         case AF_INET: {
1499                 u32 addr;
1500
1501                 if (addrlen != sizeof(u32)) {
1502                         rc = -EINVAL;
1503                         goto out;
1504                 }
1505
1506                 addr = *((u32 *)addrp);
1507
1508                 c = policydb.ocontexts[OCON_NODE];
1509                 while (c) {
1510                         if (c->u.node.addr == (addr & c->u.node.mask))
1511                                 break;
1512                         c = c->next;
1513                 }
1514                 break;
1515         }
1516
1517         case AF_INET6:
1518                 if (addrlen != sizeof(u64) * 2) {
1519                         rc = -EINVAL;
1520                         goto out;
1521                 }
1522                 c = policydb.ocontexts[OCON_NODE6];
1523                 while (c) {
1524                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1525                                                 c->u.node6.mask))
1526                                 break;
1527                         c = c->next;
1528                 }
1529                 break;
1530
1531         default:
1532                 *out_sid = SECINITSID_NODE;
1533                 goto out;
1534         }
1535
1536         if (c) {
1537                 if (!c->sid[0]) {
1538                         rc = sidtab_context_to_sid(&sidtab,
1539                                                    &c->context[0],
1540                                                    &c->sid[0]);
1541                         if (rc)
1542                                 goto out;
1543                 }
1544                 *out_sid = c->sid[0];
1545         } else {
1546                 *out_sid = SECINITSID_NODE;
1547         }
1548
1549 out:
1550         POLICY_RDUNLOCK;
1551         return rc;
1552 }
1553
1554 #define SIDS_NEL 25
1555
1556 /**
1557  * security_get_user_sids - Obtain reachable SIDs for a user.
1558  * @fromsid: starting SID
1559  * @username: username
1560  * @sids: array of reachable SIDs for user
1561  * @nel: number of elements in @sids
1562  *
1563  * Generate the set of SIDs for legal security contexts
1564  * for a given user that can be reached by @fromsid.
1565  * Set *@sids to point to a dynamically allocated
1566  * array containing the set of SIDs.  Set *@nel to the
1567  * number of elements in the array.
1568  */
1569
1570 int security_get_user_sids(u32 fromsid,
1571                            char *username,
1572                            u32 **sids,
1573                            u32 *nel)
1574 {
1575         struct context *fromcon, usercon;
1576         u32 *mysids, *mysids2, sid;
1577         u32 mynel = 0, maxnel = SIDS_NEL;
1578         struct user_datum *user;
1579         struct role_datum *role;
1580         struct av_decision avd;
1581         struct ebitmap_node *rnode, *tnode;
1582         int rc = 0, i, j;
1583
1584         if (!ss_initialized) {
1585                 *sids = NULL;
1586                 *nel = 0;
1587                 goto out;
1588         }
1589
1590         POLICY_RDLOCK;
1591
1592         fromcon = sidtab_search(&sidtab, fromsid);
1593         if (!fromcon) {
1594                 rc = -EINVAL;
1595                 goto out_unlock;
1596         }
1597
1598         user = hashtab_search(policydb.p_users.table, username);
1599         if (!user) {
1600                 rc = -EINVAL;
1601                 goto out_unlock;
1602         }
1603         usercon.user = user->value;
1604
1605         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1606         if (!mysids) {
1607                 rc = -ENOMEM;
1608                 goto out_unlock;
1609         }
1610
1611         ebitmap_for_each_bit(&user->roles, rnode, i) {
1612                 if (!ebitmap_node_get_bit(rnode, i))
1613                         continue;
1614                 role = policydb.role_val_to_struct[i];
1615                 usercon.role = i+1;
1616                 ebitmap_for_each_bit(&role->types, tnode, j) {
1617                         if (!ebitmap_node_get_bit(tnode, j))
1618                                 continue;
1619                         usercon.type = j+1;
1620
1621                         if (mls_setup_user_range(fromcon, user, &usercon))
1622                                 continue;
1623
1624                         rc = context_struct_compute_av(fromcon, &usercon,
1625                                                        SECCLASS_PROCESS,
1626                                                        PROCESS__TRANSITION,
1627                                                        &avd);
1628                         if (rc ||  !(avd.allowed & PROCESS__TRANSITION))
1629                                 continue;
1630                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1631                         if (rc) {
1632                                 kfree(mysids);
1633                                 goto out_unlock;
1634                         }
1635                         if (mynel < maxnel) {
1636                                 mysids[mynel++] = sid;
1637                         } else {
1638                                 maxnel += SIDS_NEL;
1639                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1640                                 if (!mysids2) {
1641                                         rc = -ENOMEM;
1642                                         kfree(mysids);
1643                                         goto out_unlock;
1644                                 }
1645                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1646                                 kfree(mysids);
1647                                 mysids = mysids2;
1648                                 mysids[mynel++] = sid;
1649                         }
1650                 }
1651         }
1652
1653         *sids = mysids;
1654         *nel = mynel;
1655
1656 out_unlock:
1657         POLICY_RDUNLOCK;
1658 out:
1659         return rc;
1660 }
1661
1662 /**
1663  * security_genfs_sid - Obtain a SID for a file in a filesystem
1664  * @fstype: filesystem type
1665  * @path: path from root of mount
1666  * @sclass: file security class
1667  * @sid: SID for path
1668  *
1669  * Obtain a SID to use for a file in a filesystem that
1670  * cannot support xattr or use a fixed labeling behavior like
1671  * transition SIDs or task SIDs.
1672  */
1673 int security_genfs_sid(const char *fstype,
1674                        char *path,
1675                        u16 sclass,
1676                        u32 *sid)
1677 {
1678         int len;
1679         struct genfs *genfs;
1680         struct ocontext *c;
1681         int rc = 0, cmp = 0;
1682
1683         POLICY_RDLOCK;
1684
1685         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1686                 cmp = strcmp(fstype, genfs->fstype);
1687                 if (cmp <= 0)
1688                         break;
1689         }
1690
1691         if (!genfs || cmp) {
1692                 *sid = SECINITSID_UNLABELED;
1693                 rc = -ENOENT;
1694                 goto out;
1695         }
1696
1697         for (c = genfs->head; c; c = c->next) {
1698                 len = strlen(c->u.name);
1699                 if ((!c->v.sclass || sclass == c->v.sclass) &&
1700                     (strncmp(c->u.name, path, len) == 0))
1701                         break;
1702         }
1703
1704         if (!c) {
1705                 *sid = SECINITSID_UNLABELED;
1706                 rc = -ENOENT;
1707                 goto out;
1708         }
1709
1710         if (!c->sid[0]) {
1711                 rc = sidtab_context_to_sid(&sidtab,
1712                                            &c->context[0],
1713                                            &c->sid[0]);
1714                 if (rc)
1715                         goto out;
1716         }
1717
1718         *sid = c->sid[0];
1719 out:
1720         POLICY_RDUNLOCK;
1721         return rc;
1722 }
1723
1724 /**
1725  * security_fs_use - Determine how to handle labeling for a filesystem.
1726  * @fstype: filesystem type
1727  * @behavior: labeling behavior
1728  * @sid: SID for filesystem (superblock)
1729  */
1730 int security_fs_use(
1731         const char *fstype,
1732         unsigned int *behavior,
1733         u32 *sid)
1734 {
1735         int rc = 0;
1736         struct ocontext *c;
1737
1738         POLICY_RDLOCK;
1739
1740         c = policydb.ocontexts[OCON_FSUSE];
1741         while (c) {
1742                 if (strcmp(fstype, c->u.name) == 0)
1743                         break;
1744                 c = c->next;
1745         }
1746
1747         if (c) {
1748                 *behavior = c->v.behavior;
1749                 if (!c->sid[0]) {
1750                         rc = sidtab_context_to_sid(&sidtab,
1751                                                    &c->context[0],
1752                                                    &c->sid[0]);
1753                         if (rc)
1754                                 goto out;
1755                 }
1756                 *sid = c->sid[0];
1757         } else {
1758                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1759                 if (rc) {
1760                         *behavior = SECURITY_FS_USE_NONE;
1761                         rc = 0;
1762                 } else {
1763                         *behavior = SECURITY_FS_USE_GENFS;
1764                 }
1765         }
1766
1767 out:
1768         POLICY_RDUNLOCK;
1769         return rc;
1770 }
1771
1772 int security_get_bools(int *len, char ***names, int **values)
1773 {
1774         int i, rc = -ENOMEM;
1775
1776         POLICY_RDLOCK;
1777         *names = NULL;
1778         *values = NULL;
1779
1780         *len = policydb.p_bools.nprim;
1781         if (!*len) {
1782                 rc = 0;
1783                 goto out;
1784         }
1785
1786        *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
1787         if (!*names)
1788                 goto err;
1789
1790        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
1791         if (!*values)
1792                 goto err;
1793
1794         for (i = 0; i < *len; i++) {
1795                 size_t name_len;
1796                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1797                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1798                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1799                 if (!(*names)[i])
1800                         goto err;
1801                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1802                 (*names)[i][name_len - 1] = 0;
1803         }
1804         rc = 0;
1805 out:
1806         POLICY_RDUNLOCK;
1807         return rc;
1808 err:
1809         if (*names) {
1810                 for (i = 0; i < *len; i++)
1811                         kfree((*names)[i]);
1812         }
1813         kfree(*values);
1814         goto out;
1815 }
1816
1817
1818 int security_set_bools(int len, int *values)
1819 {
1820         int i, rc = 0;
1821         int lenp, seqno = 0;
1822         struct cond_node *cur;
1823
1824         POLICY_WRLOCK;
1825
1826         lenp = policydb.p_bools.nprim;
1827         if (len != lenp) {
1828                 rc = -EFAULT;
1829                 goto out;
1830         }
1831
1832         for (i = 0; i < len; i++) {
1833                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
1834                         audit_log(current->audit_context, GFP_ATOMIC,
1835                                 AUDIT_MAC_CONFIG_CHANGE,
1836                                 "bool=%s val=%d old_val=%d auid=%u",
1837                                 policydb.p_bool_val_to_name[i],
1838                                 !!values[i],
1839                                 policydb.bool_val_to_struct[i]->state,
1840                                 audit_get_loginuid(current->audit_context));
1841                 }
1842                 if (values[i]) {
1843                         policydb.bool_val_to_struct[i]->state = 1;
1844                 } else {
1845                         policydb.bool_val_to_struct[i]->state = 0;
1846                 }
1847         }
1848
1849         for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1850                 rc = evaluate_cond_node(&policydb, cur);
1851                 if (rc)
1852                         goto out;
1853         }
1854
1855         seqno = ++latest_granting;
1856
1857 out:
1858         POLICY_WRUNLOCK;
1859         if (!rc) {
1860                 avc_ss_reset(seqno);
1861                 selnl_notify_policyload(seqno);
1862                 selinux_xfrm_notify_policyload();
1863         }
1864         return rc;
1865 }
1866
1867 int security_get_bool_value(int bool)
1868 {
1869         int rc = 0;
1870         int len;
1871
1872         POLICY_RDLOCK;
1873
1874         len = policydb.p_bools.nprim;
1875         if (bool >= len) {
1876                 rc = -EFAULT;
1877                 goto out;
1878         }
1879
1880         rc = policydb.bool_val_to_struct[bool]->state;
1881 out:
1882         POLICY_RDUNLOCK;
1883         return rc;
1884 }
1885
1886 /*
1887  * security_sid_mls_copy() - computes a new sid based on the given
1888  * sid and the mls portion of mls_sid.
1889  */
1890 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
1891 {
1892         struct context *context1;
1893         struct context *context2;
1894         struct context newcon;
1895         char *s;
1896         u32 len;
1897         int rc = 0;
1898
1899         if (!ss_initialized || !selinux_mls_enabled) {
1900                 *new_sid = sid;
1901                 goto out;
1902         }
1903
1904         context_init(&newcon);
1905
1906         POLICY_RDLOCK;
1907         context1 = sidtab_search(&sidtab, sid);
1908         if (!context1) {
1909                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1910                        "%d\n", sid);
1911                 rc = -EINVAL;
1912                 goto out_unlock;
1913         }
1914
1915         context2 = sidtab_search(&sidtab, mls_sid);
1916         if (!context2) {
1917                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1918                        "%d\n", mls_sid);
1919                 rc = -EINVAL;
1920                 goto out_unlock;
1921         }
1922
1923         newcon.user = context1->user;
1924         newcon.role = context1->role;
1925         newcon.type = context1->type;
1926         rc = mls_context_cpy(&newcon, context2);
1927         if (rc)
1928                 goto out_unlock;
1929
1930         /* Check the validity of the new context. */
1931         if (!policydb_context_isvalid(&policydb, &newcon)) {
1932                 rc = convert_context_handle_invalid_context(&newcon);
1933                 if (rc)
1934                         goto bad;
1935         }
1936
1937         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
1938         goto out_unlock;
1939
1940 bad:
1941         if (!context_struct_to_string(&newcon, &s, &len)) {
1942                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1943                           "security_sid_mls_copy: invalid context %s", s);
1944                 kfree(s);
1945         }
1946
1947 out_unlock:
1948         POLICY_RDUNLOCK;
1949         context_destroy(&newcon);
1950 out:
1951         return rc;
1952 }
1953
1954 struct selinux_audit_rule {
1955         u32 au_seqno;
1956         struct context au_ctxt;
1957 };
1958
1959 void selinux_audit_rule_free(struct selinux_audit_rule *rule)
1960 {
1961         if (rule) {
1962                 context_destroy(&rule->au_ctxt);
1963                 kfree(rule);
1964         }
1965 }
1966
1967 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
1968                             struct selinux_audit_rule **rule)
1969 {
1970         struct selinux_audit_rule *tmprule;
1971         struct role_datum *roledatum;
1972         struct type_datum *typedatum;
1973         struct user_datum *userdatum;
1974         int rc = 0;
1975
1976         *rule = NULL;
1977
1978         if (!ss_initialized)
1979                 return -ENOTSUPP;
1980
1981         switch (field) {
1982         case AUDIT_SUBJ_USER:
1983         case AUDIT_SUBJ_ROLE:
1984         case AUDIT_SUBJ_TYPE:
1985         case AUDIT_OBJ_USER:
1986         case AUDIT_OBJ_ROLE:
1987         case AUDIT_OBJ_TYPE:
1988                 /* only 'equals' and 'not equals' fit user, role, and type */
1989                 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
1990                         return -EINVAL;
1991                 break;
1992         case AUDIT_SUBJ_SEN:
1993         case AUDIT_SUBJ_CLR:
1994         case AUDIT_OBJ_LEV_LOW:
1995         case AUDIT_OBJ_LEV_HIGH:
1996                 /* we do not allow a range, indicated by the presense of '-' */
1997                 if (strchr(rulestr, '-'))
1998                         return -EINVAL;
1999                 break;
2000         default:
2001                 /* only the above fields are valid */
2002                 return -EINVAL;
2003         }
2004
2005         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2006         if (!tmprule)
2007                 return -ENOMEM;
2008
2009         context_init(&tmprule->au_ctxt);
2010
2011         POLICY_RDLOCK;
2012
2013         tmprule->au_seqno = latest_granting;
2014
2015         switch (field) {
2016         case AUDIT_SUBJ_USER:
2017         case AUDIT_OBJ_USER:
2018                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2019                 if (!userdatum)
2020                         rc = -EINVAL;
2021                 else
2022                         tmprule->au_ctxt.user = userdatum->value;
2023                 break;
2024         case AUDIT_SUBJ_ROLE:
2025         case AUDIT_OBJ_ROLE:
2026                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2027                 if (!roledatum)
2028                         rc = -EINVAL;
2029                 else
2030                         tmprule->au_ctxt.role = roledatum->value;
2031                 break;
2032         case AUDIT_SUBJ_TYPE:
2033         case AUDIT_OBJ_TYPE:
2034                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2035                 if (!typedatum)
2036                         rc = -EINVAL;
2037                 else
2038                         tmprule->au_ctxt.type = typedatum->value;
2039                 break;
2040         case AUDIT_SUBJ_SEN:
2041         case AUDIT_SUBJ_CLR:
2042         case AUDIT_OBJ_LEV_LOW:
2043         case AUDIT_OBJ_LEV_HIGH:
2044                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2045                 break;
2046         }
2047
2048         POLICY_RDUNLOCK;
2049
2050         if (rc) {
2051                 selinux_audit_rule_free(tmprule);
2052                 tmprule = NULL;
2053         }
2054
2055         *rule = tmprule;
2056
2057         return rc;
2058 }
2059
2060 int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
2061                              struct selinux_audit_rule *rule,
2062                              struct audit_context *actx)
2063 {
2064         struct context *ctxt;
2065         struct mls_level *level;
2066         int match = 0;
2067
2068         if (!rule) {
2069                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2070                           "selinux_audit_rule_match: missing rule\n");
2071                 return -ENOENT;
2072         }
2073
2074         POLICY_RDLOCK;
2075
2076         if (rule->au_seqno < latest_granting) {
2077                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2078                           "selinux_audit_rule_match: stale rule\n");
2079                 match = -ESTALE;
2080                 goto out;
2081         }
2082
2083         ctxt = sidtab_search(&sidtab, sid);
2084         if (!ctxt) {
2085                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2086                           "selinux_audit_rule_match: unrecognized SID %d\n",
2087                           sid);
2088                 match = -ENOENT;
2089                 goto out;
2090         }
2091
2092         /* a field/op pair that is not caught here will simply fall through
2093            without a match */
2094         switch (field) {
2095         case AUDIT_SUBJ_USER:
2096         case AUDIT_OBJ_USER:
2097                 switch (op) {
2098                 case AUDIT_EQUAL:
2099                         match = (ctxt->user == rule->au_ctxt.user);
2100                         break;
2101                 case AUDIT_NOT_EQUAL:
2102                         match = (ctxt->user != rule->au_ctxt.user);
2103                         break;
2104                 }
2105                 break;
2106         case AUDIT_SUBJ_ROLE:
2107         case AUDIT_OBJ_ROLE:
2108                 switch (op) {
2109                 case AUDIT_EQUAL:
2110                         match = (ctxt->role == rule->au_ctxt.role);
2111                         break;
2112                 case AUDIT_NOT_EQUAL:
2113                         match = (ctxt->role != rule->au_ctxt.role);
2114                         break;
2115                 }
2116                 break;
2117         case AUDIT_SUBJ_TYPE:
2118         case AUDIT_OBJ_TYPE:
2119                 switch (op) {
2120                 case AUDIT_EQUAL:
2121                         match = (ctxt->type == rule->au_ctxt.type);
2122                         break;
2123                 case AUDIT_NOT_EQUAL:
2124                         match = (ctxt->type != rule->au_ctxt.type);
2125                         break;
2126                 }
2127                 break;
2128         case AUDIT_SUBJ_SEN:
2129         case AUDIT_SUBJ_CLR:
2130         case AUDIT_OBJ_LEV_LOW:
2131         case AUDIT_OBJ_LEV_HIGH:
2132                 level = ((field == AUDIT_SUBJ_SEN ||
2133                           field == AUDIT_OBJ_LEV_LOW) ?
2134                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2135                 switch (op) {
2136                 case AUDIT_EQUAL:
2137                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2138                                              level);
2139                         break;
2140                 case AUDIT_NOT_EQUAL:
2141                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2142                                               level);
2143                         break;
2144                 case AUDIT_LESS_THAN:
2145                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2146                                                level) &&
2147                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2148                                                level));
2149                         break;
2150                 case AUDIT_LESS_THAN_OR_EQUAL:
2151                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2152                                               level);
2153                         break;
2154                 case AUDIT_GREATER_THAN:
2155                         match = (mls_level_dom(level,
2156                                               &rule->au_ctxt.range.level[0]) &&
2157                                  !mls_level_eq(level,
2158                                                &rule->au_ctxt.range.level[0]));
2159                         break;
2160                 case AUDIT_GREATER_THAN_OR_EQUAL:
2161                         match = mls_level_dom(level,
2162                                               &rule->au_ctxt.range.level[0]);
2163                         break;
2164                 }
2165         }
2166
2167 out:
2168         POLICY_RDUNLOCK;
2169         return match;
2170 }
2171
2172 static int (*aurule_callback)(void) = NULL;
2173
2174 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2175                                u16 class, u32 perms, u32 *retained)
2176 {
2177         int err = 0;
2178
2179         if (event == AVC_CALLBACK_RESET && aurule_callback)
2180                 err = aurule_callback();
2181         return err;
2182 }
2183
2184 static int __init aurule_init(void)
2185 {
2186         int err;
2187
2188         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2189                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2190         if (err)
2191                 panic("avc_add_callback() failed, error %d\n", err);
2192
2193         return err;
2194 }
2195 __initcall(aurule_init);
2196
2197 void selinux_audit_set_callback(int (*callback)(void))
2198 {
2199         aurule_callback = callback;
2200 }
2201
2202 #ifdef CONFIG_NETLABEL
2203 /*
2204  * NetLabel cache structure
2205  */
2206 #define NETLBL_CACHE(x)           ((struct selinux_netlbl_cache *)(x))
2207 #define NETLBL_CACHE_T_NONE       0
2208 #define NETLBL_CACHE_T_SID        1
2209 #define NETLBL_CACHE_T_MLS        2
2210 struct selinux_netlbl_cache {
2211         u32 type;
2212         union {
2213                 u32 sid;
2214                 struct mls_range mls_label;
2215         } data;
2216 };
2217
2218 /**
2219  * security_netlbl_cache_free - Free the NetLabel cached data
2220  * @data: the data to free
2221  *
2222  * Description:
2223  * This function is intended to be used as the free() callback inside the
2224  * netlbl_lsm_cache structure.
2225  *
2226  */
2227 static void security_netlbl_cache_free(const void *data)
2228 {
2229         struct selinux_netlbl_cache *cache;
2230
2231         if (data == NULL)
2232                 return;
2233
2234         cache = NETLBL_CACHE(data);
2235         switch (cache->type) {
2236         case NETLBL_CACHE_T_MLS:
2237                 ebitmap_destroy(&cache->data.mls_label.level[0].cat);
2238                 break;
2239         }
2240         kfree(data);
2241 }
2242
2243 /**
2244  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2245  * @secattr: the NetLabel packet security attributes
2246  * @ctx: the SELinux context
2247  *
2248  * Description:
2249  * Attempt to cache the context in @ctx, which was derived from the packet in
2250  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2251  * already been initialized.
2252  *
2253  */
2254 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2255                                       struct context *ctx)
2256 {
2257         struct selinux_netlbl_cache *cache = NULL;
2258
2259         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2260         if (secattr->cache == NULL)
2261                 return;
2262
2263         cache = kzalloc(sizeof(*cache), GFP_ATOMIC);
2264         if (cache == NULL)
2265                 return;
2266
2267         cache->type = NETLBL_CACHE_T_MLS;
2268         if (ebitmap_cpy(&cache->data.mls_label.level[0].cat,
2269                         &ctx->range.level[0].cat) != 0)
2270                 return;
2271         cache->data.mls_label.level[1].cat.highbit =
2272                 cache->data.mls_label.level[0].cat.highbit;
2273         cache->data.mls_label.level[1].cat.node =
2274                 cache->data.mls_label.level[0].cat.node;
2275         cache->data.mls_label.level[0].sens = ctx->range.level[0].sens;
2276         cache->data.mls_label.level[1].sens = ctx->range.level[0].sens;
2277
2278         secattr->cache->free = security_netlbl_cache_free;
2279         secattr->cache->data = (void *)cache;
2280         secattr->flags |= NETLBL_SECATTR_CACHE;
2281 }
2282
2283 /**
2284  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2285  * @secattr: the NetLabel packet security attributes
2286  * @base_sid: the SELinux SID to use as a context for MLS only attributes
2287  * @sid: the SELinux SID
2288  *
2289  * Description:
2290  * Convert the given NetLabel security attributes in @secattr into a
2291  * SELinux SID.  If the @secattr field does not contain a full SELinux
2292  * SID/context then use the context in @base_sid as the foundation.  If
2293  * possibile the 'cache' field of @secattr is set and the CACHE flag is set;
2294  * this is to allow the @secattr to be used by NetLabel to cache the secattr to
2295  * SID conversion for future lookups.  Returns zero on success, negative
2296  * values on failure.
2297  *
2298  */
2299 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2300                                    u32 base_sid,
2301                                    u32 *sid)
2302 {
2303         int rc = -EIDRM;
2304         struct context *ctx;
2305         struct context ctx_new;
2306         struct selinux_netlbl_cache *cache;
2307
2308         if (!ss_initialized) {
2309                 *sid = SECSID_NULL;
2310                 return 0;
2311         }
2312
2313         POLICY_RDLOCK;
2314
2315         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2316                 cache = NETLBL_CACHE(secattr->cache->data);
2317                 switch (cache->type) {
2318                 case NETLBL_CACHE_T_SID:
2319                         *sid = cache->data.sid;
2320                         rc = 0;
2321                         break;
2322                 case NETLBL_CACHE_T_MLS:
2323                         ctx = sidtab_search(&sidtab, base_sid);
2324                         if (ctx == NULL)
2325                                 goto netlbl_secattr_to_sid_return;
2326
2327                         ctx_new.user = ctx->user;
2328                         ctx_new.role = ctx->role;
2329                         ctx_new.type = ctx->type;
2330                         ctx_new.range.level[0].sens =
2331                                 cache->data.mls_label.level[0].sens;
2332                         ctx_new.range.level[0].cat.highbit =
2333                                 cache->data.mls_label.level[0].cat.highbit;
2334                         ctx_new.range.level[0].cat.node =
2335                                 cache->data.mls_label.level[0].cat.node;
2336                         ctx_new.range.level[1].sens =
2337                                 cache->data.mls_label.level[1].sens;
2338                         ctx_new.range.level[1].cat.highbit =
2339                                 cache->data.mls_label.level[1].cat.highbit;
2340                         ctx_new.range.level[1].cat.node =
2341                                 cache->data.mls_label.level[1].cat.node;
2342
2343                         rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2344                         break;
2345                 default:
2346                         goto netlbl_secattr_to_sid_return;
2347                 }
2348         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2349                 ctx = sidtab_search(&sidtab, base_sid);
2350                 if (ctx == NULL)
2351                         goto netlbl_secattr_to_sid_return;
2352
2353                 ctx_new.user = ctx->user;
2354                 ctx_new.role = ctx->role;
2355                 ctx_new.type = ctx->type;
2356                 mls_import_netlbl_lvl(&ctx_new, secattr);
2357                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2358                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2359                                                   secattr->mls_cat) != 0)
2360                                 goto netlbl_secattr_to_sid_return;
2361                         ctx_new.range.level[1].cat.highbit =
2362                                 ctx_new.range.level[0].cat.highbit;
2363                         ctx_new.range.level[1].cat.node =
2364                                 ctx_new.range.level[0].cat.node;
2365                 } else {
2366                         ebitmap_init(&ctx_new.range.level[0].cat);
2367                         ebitmap_init(&ctx_new.range.level[1].cat);
2368                 }
2369                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2370                         goto netlbl_secattr_to_sid_return_cleanup;
2371
2372                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2373                 if (rc != 0)
2374                         goto netlbl_secattr_to_sid_return_cleanup;
2375
2376                 security_netlbl_cache_add(secattr, &ctx_new);
2377
2378                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2379         } else {
2380                 *sid = SECSID_NULL;
2381                 rc = 0;
2382         }
2383
2384 netlbl_secattr_to_sid_return:
2385         POLICY_RDUNLOCK;
2386         return rc;
2387 netlbl_secattr_to_sid_return_cleanup:
2388         ebitmap_destroy(&ctx_new.range.level[0].cat);
2389         goto netlbl_secattr_to_sid_return;
2390 }
2391
2392 /**
2393  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2394  * @sid: the SELinux SID
2395  * @secattr: the NetLabel packet security attributes
2396  *
2397  * Description:
2398  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2399  * Returns zero on success, negative values on failure.
2400  *
2401  */
2402 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2403 {
2404         int rc = -ENOENT;
2405         struct context *ctx;
2406
2407         netlbl_secattr_init(secattr);
2408
2409         if (!ss_initialized)
2410                 return 0;
2411
2412         POLICY_RDLOCK;
2413         ctx = sidtab_search(&sidtab, sid);
2414         if (ctx == NULL)
2415                 goto netlbl_sid_to_secattr_failure;
2416         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2417                                   GFP_ATOMIC);
2418         secattr->flags |= NETLBL_SECATTR_DOMAIN;
2419         mls_export_netlbl_lvl(ctx, secattr);
2420         rc = mls_export_netlbl_cat(ctx, secattr);
2421         if (rc != 0)
2422                 goto netlbl_sid_to_secattr_failure;
2423         POLICY_RDUNLOCK;
2424
2425         return 0;
2426
2427 netlbl_sid_to_secattr_failure:
2428         POLICY_RDUNLOCK;
2429         netlbl_secattr_destroy(secattr);
2430         return rc;
2431 }
2432 #endif /* CONFIG_NETLABEL */