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 (i > p->p_classes.nprim) {
1053                         printk(KERN_INFO
1054                                "security:  class %s not defined in policy\n",
1055                                def_class);
1056                         continue;
1057                 }
1058                 pol_class = p->p_class_val_to_name[i-1];
1059                 if (strcmp(pol_class, def_class)) {
1060                         printk(KERN_ERR
1061                                "security:  class %d is incorrect, found %s but should be %s\n",
1062                                i, pol_class, def_class);
1063                         return -EINVAL;
1064                 }
1065         }
1066         for (i = 0; i < kdefs->av_pts_len; i++) {
1067                 class_val = kdefs->av_perm_to_string[i].tclass;
1068                 perm_val = kdefs->av_perm_to_string[i].value;
1069                 def_perm = kdefs->av_perm_to_string[i].name;
1070                 if (class_val > p->p_classes.nprim)
1071                         continue;
1072                 pol_class = p->p_class_val_to_name[class_val-1];
1073                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1074                 BUG_ON(!cladatum);
1075                 perms = &cladatum->permissions;
1076                 nprim = 1 << (perms->nprim - 1);
1077                 if (perm_val > nprim) {
1078                         printk(KERN_INFO
1079                                "security:  permission %s in class %s not defined in policy\n",
1080                                def_perm, pol_class);
1081                         continue;
1082                 }
1083                 perdatum = hashtab_search(perms->table, def_perm);
1084                 if (perdatum == NULL) {
1085                         printk(KERN_ERR
1086                                "security:  permission %s in class %s not found in policy\n",
1087                                def_perm, pol_class);
1088                         return -EINVAL;
1089                 }
1090                 pol_val = 1 << (perdatum->value - 1);
1091                 if (pol_val != perm_val) {
1092                         printk(KERN_ERR
1093                                "security:  permission %s in class %s has incorrect value\n",
1094                                def_perm, pol_class);
1095                         return -EINVAL;
1096                 }
1097         }
1098         for (i = 0; i < kdefs->av_inherit_len; i++) {
1099                 class_val = kdefs->av_inherit[i].tclass;
1100                 if (class_val > p->p_classes.nprim)
1101                         continue;
1102                 pol_class = p->p_class_val_to_name[class_val-1];
1103                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1104                 BUG_ON(!cladatum);
1105                 if (!cladatum->comdatum) {
1106                         printk(KERN_ERR
1107                                "security:  class %s should have an inherits clause but does not\n",
1108                                pol_class);
1109                         return -EINVAL;
1110                 }
1111                 tmp = kdefs->av_inherit[i].common_base;
1112                 common_pts_len = 0;
1113                 while (!(tmp & 0x01)) {
1114                         common_pts_len++;
1115                         tmp >>= 1;
1116                 }
1117                 perms = &cladatum->comdatum->permissions;
1118                 for (j = 0; j < common_pts_len; j++) {
1119                         def_perm = kdefs->av_inherit[i].common_pts[j];
1120                         if (j >= perms->nprim) {
1121                                 printk(KERN_INFO
1122                                        "security:  permission %s in class %s not defined in policy\n",
1123                                        def_perm, pol_class);
1124                                 continue;
1125                         }
1126                         perdatum = hashtab_search(perms->table, def_perm);
1127                         if (perdatum == NULL) {
1128                                 printk(KERN_ERR
1129                                        "security:  permission %s in class %s not found in policy\n",
1130                                        def_perm, pol_class);
1131                                 return -EINVAL;
1132                         }
1133                         if (perdatum->value != j + 1) {
1134                                 printk(KERN_ERR
1135                                        "security:  permission %s in class %s has incorrect value\n",
1136                                        def_perm, pol_class);
1137                                 return -EINVAL;
1138                         }
1139                 }
1140         }
1141         return 0;
1142 }
1143
1144 /* Clone the SID into the new SID table. */
1145 static int clone_sid(u32 sid,
1146                      struct context *context,
1147                      void *arg)
1148 {
1149         struct sidtab *s = arg;
1150
1151         return sidtab_insert(s, sid, context);
1152 }
1153
1154 static inline int convert_context_handle_invalid_context(struct context *context)
1155 {
1156         int rc = 0;
1157
1158         if (selinux_enforcing) {
1159                 rc = -EINVAL;
1160         } else {
1161                 char *s;
1162                 u32 len;
1163
1164                 context_struct_to_string(context, &s, &len);
1165                 printk(KERN_ERR "security:  context %s is invalid\n", s);
1166                 kfree(s);
1167         }
1168         return rc;
1169 }
1170
1171 struct convert_context_args {
1172         struct policydb *oldp;
1173         struct policydb *newp;
1174 };
1175
1176 /*
1177  * Convert the values in the security context
1178  * structure `c' from the values specified
1179  * in the policy `p->oldp' to the values specified
1180  * in the policy `p->newp'.  Verify that the
1181  * context is valid under the new policy.
1182  */
1183 static int convert_context(u32 key,
1184                            struct context *c,
1185                            void *p)
1186 {
1187         struct convert_context_args *args;
1188         struct context oldc;
1189         struct role_datum *role;
1190         struct type_datum *typdatum;
1191         struct user_datum *usrdatum;
1192         char *s;
1193         u32 len;
1194         int rc;
1195
1196         args = p;
1197
1198         rc = context_cpy(&oldc, c);
1199         if (rc)
1200                 goto out;
1201
1202         rc = -EINVAL;
1203
1204         /* Convert the user. */
1205         usrdatum = hashtab_search(args->newp->p_users.table,
1206                                   args->oldp->p_user_val_to_name[c->user - 1]);
1207         if (!usrdatum) {
1208                 goto bad;
1209         }
1210         c->user = usrdatum->value;
1211
1212         /* Convert the role. */
1213         role = hashtab_search(args->newp->p_roles.table,
1214                               args->oldp->p_role_val_to_name[c->role - 1]);
1215         if (!role) {
1216                 goto bad;
1217         }
1218         c->role = role->value;
1219
1220         /* Convert the type. */
1221         typdatum = hashtab_search(args->newp->p_types.table,
1222                                   args->oldp->p_type_val_to_name[c->type - 1]);
1223         if (!typdatum) {
1224                 goto bad;
1225         }
1226         c->type = typdatum->value;
1227
1228         rc = mls_convert_context(args->oldp, args->newp, c);
1229         if (rc)
1230                 goto bad;
1231
1232         /* Check the validity of the new context. */
1233         if (!policydb_context_isvalid(args->newp, c)) {
1234                 rc = convert_context_handle_invalid_context(&oldc);
1235                 if (rc)
1236                         goto bad;
1237         }
1238
1239         context_destroy(&oldc);
1240 out:
1241         return rc;
1242 bad:
1243         context_struct_to_string(&oldc, &s, &len);
1244         context_destroy(&oldc);
1245         printk(KERN_ERR "security:  invalidating context %s\n", s);
1246         kfree(s);
1247         goto out;
1248 }
1249
1250 extern void selinux_complete_init(void);
1251
1252 /**
1253  * security_load_policy - Load a security policy configuration.
1254  * @data: binary policy data
1255  * @len: length of data in bytes
1256  *
1257  * Load a new set of security policy configuration data,
1258  * validate it and convert the SID table as necessary.
1259  * This function will flush the access vector cache after
1260  * loading the new policy.
1261  */
1262 int security_load_policy(void *data, size_t len)
1263 {
1264         struct policydb oldpolicydb, newpolicydb;
1265         struct sidtab oldsidtab, newsidtab;
1266         struct convert_context_args args;
1267         u32 seqno;
1268         int rc = 0;
1269         struct policy_file file = { data, len }, *fp = &file;
1270
1271         LOAD_LOCK;
1272
1273         if (!ss_initialized) {
1274                 avtab_cache_init();
1275                 if (policydb_read(&policydb, fp)) {
1276                         LOAD_UNLOCK;
1277                         avtab_cache_destroy();
1278                         return -EINVAL;
1279                 }
1280                 if (policydb_load_isids(&policydb, &sidtab)) {
1281                         LOAD_UNLOCK;
1282                         policydb_destroy(&policydb);
1283                         avtab_cache_destroy();
1284                         return -EINVAL;
1285                 }
1286                 /* Verify that the kernel defined classes are correct. */
1287                 if (validate_classes(&policydb)) {
1288                         printk(KERN_ERR
1289                                "security:  the definition of a class is incorrect\n");
1290                         LOAD_UNLOCK;
1291                         sidtab_destroy(&sidtab);
1292                         policydb_destroy(&policydb);
1293                         avtab_cache_destroy();
1294                         return -EINVAL;
1295                 }
1296                 policydb_loaded_version = policydb.policyvers;
1297                 ss_initialized = 1;
1298                 seqno = ++latest_granting;
1299                 LOAD_UNLOCK;
1300                 selinux_complete_init();
1301                 avc_ss_reset(seqno);
1302                 selnl_notify_policyload(seqno);
1303                 selinux_netlbl_cache_invalidate();
1304                 selinux_xfrm_notify_policyload();
1305                 return 0;
1306         }
1307
1308 #if 0
1309         sidtab_hash_eval(&sidtab, "sids");
1310 #endif
1311
1312         if (policydb_read(&newpolicydb, fp)) {
1313                 LOAD_UNLOCK;
1314                 return -EINVAL;
1315         }
1316
1317         sidtab_init(&newsidtab);
1318
1319         /* Verify that the kernel defined classes are correct. */
1320         if (validate_classes(&newpolicydb)) {
1321                 printk(KERN_ERR
1322                        "security:  the definition of a class is incorrect\n");
1323                 rc = -EINVAL;
1324                 goto err;
1325         }
1326
1327         /* Clone the SID table. */
1328         sidtab_shutdown(&sidtab);
1329         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1330                 rc = -ENOMEM;
1331                 goto err;
1332         }
1333
1334         /* Convert the internal representations of contexts
1335            in the new SID table and remove invalid SIDs. */
1336         args.oldp = &policydb;
1337         args.newp = &newpolicydb;
1338         sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1339
1340         /* Save the old policydb and SID table to free later. */
1341         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1342         sidtab_set(&oldsidtab, &sidtab);
1343
1344         /* Install the new policydb and SID table. */
1345         POLICY_WRLOCK;
1346         memcpy(&policydb, &newpolicydb, sizeof policydb);
1347         sidtab_set(&sidtab, &newsidtab);
1348         seqno = ++latest_granting;
1349         policydb_loaded_version = policydb.policyvers;
1350         POLICY_WRUNLOCK;
1351         LOAD_UNLOCK;
1352
1353         /* Free the old policydb and SID table. */
1354         policydb_destroy(&oldpolicydb);
1355         sidtab_destroy(&oldsidtab);
1356
1357         avc_ss_reset(seqno);
1358         selnl_notify_policyload(seqno);
1359         selinux_netlbl_cache_invalidate();
1360         selinux_xfrm_notify_policyload();
1361
1362         return 0;
1363
1364 err:
1365         LOAD_UNLOCK;
1366         sidtab_destroy(&newsidtab);
1367         policydb_destroy(&newpolicydb);
1368         return rc;
1369
1370 }
1371
1372 /**
1373  * security_port_sid - Obtain the SID for a port.
1374  * @domain: communication domain aka address family
1375  * @type: socket type
1376  * @protocol: protocol number
1377  * @port: port number
1378  * @out_sid: security identifier
1379  */
1380 int security_port_sid(u16 domain,
1381                       u16 type,
1382                       u8 protocol,
1383                       u16 port,
1384                       u32 *out_sid)
1385 {
1386         struct ocontext *c;
1387         int rc = 0;
1388
1389         POLICY_RDLOCK;
1390
1391         c = policydb.ocontexts[OCON_PORT];
1392         while (c) {
1393                 if (c->u.port.protocol == protocol &&
1394                     c->u.port.low_port <= port &&
1395                     c->u.port.high_port >= port)
1396                         break;
1397                 c = c->next;
1398         }
1399
1400         if (c) {
1401                 if (!c->sid[0]) {
1402                         rc = sidtab_context_to_sid(&sidtab,
1403                                                    &c->context[0],
1404                                                    &c->sid[0]);
1405                         if (rc)
1406                                 goto out;
1407                 }
1408                 *out_sid = c->sid[0];
1409         } else {
1410                 *out_sid = SECINITSID_PORT;
1411         }
1412
1413 out:
1414         POLICY_RDUNLOCK;
1415         return rc;
1416 }
1417
1418 /**
1419  * security_netif_sid - Obtain the SID for a network interface.
1420  * @name: interface name
1421  * @if_sid: interface SID
1422  * @msg_sid: default SID for received packets
1423  */
1424 int security_netif_sid(char *name,
1425                        u32 *if_sid,
1426                        u32 *msg_sid)
1427 {
1428         int rc = 0;
1429         struct ocontext *c;
1430
1431         POLICY_RDLOCK;
1432
1433         c = policydb.ocontexts[OCON_NETIF];
1434         while (c) {
1435                 if (strcmp(name, c->u.name) == 0)
1436                         break;
1437                 c = c->next;
1438         }
1439
1440         if (c) {
1441                 if (!c->sid[0] || !c->sid[1]) {
1442                         rc = sidtab_context_to_sid(&sidtab,
1443                                                   &c->context[0],
1444                                                   &c->sid[0]);
1445                         if (rc)
1446                                 goto out;
1447                         rc = sidtab_context_to_sid(&sidtab,
1448                                                    &c->context[1],
1449                                                    &c->sid[1]);
1450                         if (rc)
1451                                 goto out;
1452                 }
1453                 *if_sid = c->sid[0];
1454                 *msg_sid = c->sid[1];
1455         } else {
1456                 *if_sid = SECINITSID_NETIF;
1457                 *msg_sid = SECINITSID_NETMSG;
1458         }
1459
1460 out:
1461         POLICY_RDUNLOCK;
1462         return rc;
1463 }
1464
1465 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1466 {
1467         int i, fail = 0;
1468
1469         for(i = 0; i < 4; i++)
1470                 if(addr[i] != (input[i] & mask[i])) {
1471                         fail = 1;
1472                         break;
1473                 }
1474
1475         return !fail;
1476 }
1477
1478 /**
1479  * security_node_sid - Obtain the SID for a node (host).
1480  * @domain: communication domain aka address family
1481  * @addrp: address
1482  * @addrlen: address length in bytes
1483  * @out_sid: security identifier
1484  */
1485 int security_node_sid(u16 domain,
1486                       void *addrp,
1487                       u32 addrlen,
1488                       u32 *out_sid)
1489 {
1490         int rc = 0;
1491         struct ocontext *c;
1492
1493         POLICY_RDLOCK;
1494
1495         switch (domain) {
1496         case AF_INET: {
1497                 u32 addr;
1498
1499                 if (addrlen != sizeof(u32)) {
1500                         rc = -EINVAL;
1501                         goto out;
1502                 }
1503
1504                 addr = *((u32 *)addrp);
1505
1506                 c = policydb.ocontexts[OCON_NODE];
1507                 while (c) {
1508                         if (c->u.node.addr == (addr & c->u.node.mask))
1509                                 break;
1510                         c = c->next;
1511                 }
1512                 break;
1513         }
1514
1515         case AF_INET6:
1516                 if (addrlen != sizeof(u64) * 2) {
1517                         rc = -EINVAL;
1518                         goto out;
1519                 }
1520                 c = policydb.ocontexts[OCON_NODE6];
1521                 while (c) {
1522                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1523                                                 c->u.node6.mask))
1524                                 break;
1525                         c = c->next;
1526                 }
1527                 break;
1528
1529         default:
1530                 *out_sid = SECINITSID_NODE;
1531                 goto out;
1532         }
1533
1534         if (c) {
1535                 if (!c->sid[0]) {
1536                         rc = sidtab_context_to_sid(&sidtab,
1537                                                    &c->context[0],
1538                                                    &c->sid[0]);
1539                         if (rc)
1540                                 goto out;
1541                 }
1542                 *out_sid = c->sid[0];
1543         } else {
1544                 *out_sid = SECINITSID_NODE;
1545         }
1546
1547 out:
1548         POLICY_RDUNLOCK;
1549         return rc;
1550 }
1551
1552 #define SIDS_NEL 25
1553
1554 /**
1555  * security_get_user_sids - Obtain reachable SIDs for a user.
1556  * @fromsid: starting SID
1557  * @username: username
1558  * @sids: array of reachable SIDs for user
1559  * @nel: number of elements in @sids
1560  *
1561  * Generate the set of SIDs for legal security contexts
1562  * for a given user that can be reached by @fromsid.
1563  * Set *@sids to point to a dynamically allocated
1564  * array containing the set of SIDs.  Set *@nel to the
1565  * number of elements in the array.
1566  */
1567
1568 int security_get_user_sids(u32 fromsid,
1569                            char *username,
1570                            u32 **sids,
1571                            u32 *nel)
1572 {
1573         struct context *fromcon, usercon;
1574         u32 *mysids, *mysids2, sid;
1575         u32 mynel = 0, maxnel = SIDS_NEL;
1576         struct user_datum *user;
1577         struct role_datum *role;
1578         struct av_decision avd;
1579         struct ebitmap_node *rnode, *tnode;
1580         int rc = 0, i, j;
1581
1582         if (!ss_initialized) {
1583                 *sids = NULL;
1584                 *nel = 0;
1585                 goto out;
1586         }
1587
1588         POLICY_RDLOCK;
1589
1590         fromcon = sidtab_search(&sidtab, fromsid);
1591         if (!fromcon) {
1592                 rc = -EINVAL;
1593                 goto out_unlock;
1594         }
1595
1596         user = hashtab_search(policydb.p_users.table, username);
1597         if (!user) {
1598                 rc = -EINVAL;
1599                 goto out_unlock;
1600         }
1601         usercon.user = user->value;
1602
1603         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1604         if (!mysids) {
1605                 rc = -ENOMEM;
1606                 goto out_unlock;
1607         }
1608
1609         ebitmap_for_each_bit(&user->roles, rnode, i) {
1610                 if (!ebitmap_node_get_bit(rnode, i))
1611                         continue;
1612                 role = policydb.role_val_to_struct[i];
1613                 usercon.role = i+1;
1614                 ebitmap_for_each_bit(&role->types, tnode, j) {
1615                         if (!ebitmap_node_get_bit(tnode, j))
1616                                 continue;
1617                         usercon.type = j+1;
1618
1619                         if (mls_setup_user_range(fromcon, user, &usercon))
1620                                 continue;
1621
1622                         rc = context_struct_compute_av(fromcon, &usercon,
1623                                                        SECCLASS_PROCESS,
1624                                                        PROCESS__TRANSITION,
1625                                                        &avd);
1626                         if (rc ||  !(avd.allowed & PROCESS__TRANSITION))
1627                                 continue;
1628                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1629                         if (rc) {
1630                                 kfree(mysids);
1631                                 goto out_unlock;
1632                         }
1633                         if (mynel < maxnel) {
1634                                 mysids[mynel++] = sid;
1635                         } else {
1636                                 maxnel += SIDS_NEL;
1637                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1638                                 if (!mysids2) {
1639                                         rc = -ENOMEM;
1640                                         kfree(mysids);
1641                                         goto out_unlock;
1642                                 }
1643                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1644                                 kfree(mysids);
1645                                 mysids = mysids2;
1646                                 mysids[mynel++] = sid;
1647                         }
1648                 }
1649         }
1650
1651         *sids = mysids;
1652         *nel = mynel;
1653
1654 out_unlock:
1655         POLICY_RDUNLOCK;
1656 out:
1657         return rc;
1658 }
1659
1660 /**
1661  * security_genfs_sid - Obtain a SID for a file in a filesystem
1662  * @fstype: filesystem type
1663  * @path: path from root of mount
1664  * @sclass: file security class
1665  * @sid: SID for path
1666  *
1667  * Obtain a SID to use for a file in a filesystem that
1668  * cannot support xattr or use a fixed labeling behavior like
1669  * transition SIDs or task SIDs.
1670  */
1671 int security_genfs_sid(const char *fstype,
1672                        char *path,
1673                        u16 sclass,
1674                        u32 *sid)
1675 {
1676         int len;
1677         struct genfs *genfs;
1678         struct ocontext *c;
1679         int rc = 0, cmp = 0;
1680
1681         POLICY_RDLOCK;
1682
1683         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1684                 cmp = strcmp(fstype, genfs->fstype);
1685                 if (cmp <= 0)
1686                         break;
1687         }
1688
1689         if (!genfs || cmp) {
1690                 *sid = SECINITSID_UNLABELED;
1691                 rc = -ENOENT;
1692                 goto out;
1693         }
1694
1695         for (c = genfs->head; c; c = c->next) {
1696                 len = strlen(c->u.name);
1697                 if ((!c->v.sclass || sclass == c->v.sclass) &&
1698                     (strncmp(c->u.name, path, len) == 0))
1699                         break;
1700         }
1701
1702         if (!c) {
1703                 *sid = SECINITSID_UNLABELED;
1704                 rc = -ENOENT;
1705                 goto out;
1706         }
1707
1708         if (!c->sid[0]) {
1709                 rc = sidtab_context_to_sid(&sidtab,
1710                                            &c->context[0],
1711                                            &c->sid[0]);
1712                 if (rc)
1713                         goto out;
1714         }
1715
1716         *sid = c->sid[0];
1717 out:
1718         POLICY_RDUNLOCK;
1719         return rc;
1720 }
1721
1722 /**
1723  * security_fs_use - Determine how to handle labeling for a filesystem.
1724  * @fstype: filesystem type
1725  * @behavior: labeling behavior
1726  * @sid: SID for filesystem (superblock)
1727  */
1728 int security_fs_use(
1729         const char *fstype,
1730         unsigned int *behavior,
1731         u32 *sid)
1732 {
1733         int rc = 0;
1734         struct ocontext *c;
1735
1736         POLICY_RDLOCK;
1737
1738         c = policydb.ocontexts[OCON_FSUSE];
1739         while (c) {
1740                 if (strcmp(fstype, c->u.name) == 0)
1741                         break;
1742                 c = c->next;
1743         }
1744
1745         if (c) {
1746                 *behavior = c->v.behavior;
1747                 if (!c->sid[0]) {
1748                         rc = sidtab_context_to_sid(&sidtab,
1749                                                    &c->context[0],
1750                                                    &c->sid[0]);
1751                         if (rc)
1752                                 goto out;
1753                 }
1754                 *sid = c->sid[0];
1755         } else {
1756                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1757                 if (rc) {
1758                         *behavior = SECURITY_FS_USE_NONE;
1759                         rc = 0;
1760                 } else {
1761                         *behavior = SECURITY_FS_USE_GENFS;
1762                 }
1763         }
1764
1765 out:
1766         POLICY_RDUNLOCK;
1767         return rc;
1768 }
1769
1770 int security_get_bools(int *len, char ***names, int **values)
1771 {
1772         int i, rc = -ENOMEM;
1773
1774         POLICY_RDLOCK;
1775         *names = NULL;
1776         *values = NULL;
1777
1778         *len = policydb.p_bools.nprim;
1779         if (!*len) {
1780                 rc = 0;
1781                 goto out;
1782         }
1783
1784        *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
1785         if (!*names)
1786                 goto err;
1787
1788        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
1789         if (!*values)
1790                 goto err;
1791
1792         for (i = 0; i < *len; i++) {
1793                 size_t name_len;
1794                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1795                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1796                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1797                 if (!(*names)[i])
1798                         goto err;
1799                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1800                 (*names)[i][name_len - 1] = 0;
1801         }
1802         rc = 0;
1803 out:
1804         POLICY_RDUNLOCK;
1805         return rc;
1806 err:
1807         if (*names) {
1808                 for (i = 0; i < *len; i++)
1809                         kfree((*names)[i]);
1810         }
1811         kfree(*values);
1812         goto out;
1813 }
1814
1815
1816 int security_set_bools(int len, int *values)
1817 {
1818         int i, rc = 0;
1819         int lenp, seqno = 0;
1820         struct cond_node *cur;
1821
1822         POLICY_WRLOCK;
1823
1824         lenp = policydb.p_bools.nprim;
1825         if (len != lenp) {
1826                 rc = -EFAULT;
1827                 goto out;
1828         }
1829
1830         for (i = 0; i < len; i++) {
1831                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
1832                         audit_log(current->audit_context, GFP_ATOMIC,
1833                                 AUDIT_MAC_CONFIG_CHANGE,
1834                                 "bool=%s val=%d old_val=%d auid=%u",
1835                                 policydb.p_bool_val_to_name[i],
1836                                 !!values[i],
1837                                 policydb.bool_val_to_struct[i]->state,
1838                                 audit_get_loginuid(current->audit_context));
1839                 }
1840                 if (values[i]) {
1841                         policydb.bool_val_to_struct[i]->state = 1;
1842                 } else {
1843                         policydb.bool_val_to_struct[i]->state = 0;
1844                 }
1845         }
1846
1847         for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1848                 rc = evaluate_cond_node(&policydb, cur);
1849                 if (rc)
1850                         goto out;
1851         }
1852
1853         seqno = ++latest_granting;
1854
1855 out:
1856         POLICY_WRUNLOCK;
1857         if (!rc) {
1858                 avc_ss_reset(seqno);
1859                 selnl_notify_policyload(seqno);
1860                 selinux_xfrm_notify_policyload();
1861         }
1862         return rc;
1863 }
1864
1865 int security_get_bool_value(int bool)
1866 {
1867         int rc = 0;
1868         int len;
1869
1870         POLICY_RDLOCK;
1871
1872         len = policydb.p_bools.nprim;
1873         if (bool >= len) {
1874                 rc = -EFAULT;
1875                 goto out;
1876         }
1877
1878         rc = policydb.bool_val_to_struct[bool]->state;
1879 out:
1880         POLICY_RDUNLOCK;
1881         return rc;
1882 }
1883
1884 /*
1885  * security_sid_mls_copy() - computes a new sid based on the given
1886  * sid and the mls portion of mls_sid.
1887  */
1888 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
1889 {
1890         struct context *context1;
1891         struct context *context2;
1892         struct context newcon;
1893         char *s;
1894         u32 len;
1895         int rc = 0;
1896
1897         if (!ss_initialized || !selinux_mls_enabled) {
1898                 *new_sid = sid;
1899                 goto out;
1900         }
1901
1902         context_init(&newcon);
1903
1904         POLICY_RDLOCK;
1905         context1 = sidtab_search(&sidtab, sid);
1906         if (!context1) {
1907                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1908                        "%d\n", sid);
1909                 rc = -EINVAL;
1910                 goto out_unlock;
1911         }
1912
1913         context2 = sidtab_search(&sidtab, mls_sid);
1914         if (!context2) {
1915                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1916                        "%d\n", mls_sid);
1917                 rc = -EINVAL;
1918                 goto out_unlock;
1919         }
1920
1921         newcon.user = context1->user;
1922         newcon.role = context1->role;
1923         newcon.type = context1->type;
1924         rc = mls_context_cpy(&newcon, context2);
1925         if (rc)
1926                 goto out_unlock;
1927
1928         /* Check the validity of the new context. */
1929         if (!policydb_context_isvalid(&policydb, &newcon)) {
1930                 rc = convert_context_handle_invalid_context(&newcon);
1931                 if (rc)
1932                         goto bad;
1933         }
1934
1935         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
1936         goto out_unlock;
1937
1938 bad:
1939         if (!context_struct_to_string(&newcon, &s, &len)) {
1940                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1941                           "security_sid_mls_copy: invalid context %s", s);
1942                 kfree(s);
1943         }
1944
1945 out_unlock:
1946         POLICY_RDUNLOCK;
1947         context_destroy(&newcon);
1948 out:
1949         return rc;
1950 }
1951
1952 struct selinux_audit_rule {
1953         u32 au_seqno;
1954         struct context au_ctxt;
1955 };
1956
1957 void selinux_audit_rule_free(struct selinux_audit_rule *rule)
1958 {
1959         if (rule) {
1960                 context_destroy(&rule->au_ctxt);
1961                 kfree(rule);
1962         }
1963 }
1964
1965 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
1966                             struct selinux_audit_rule **rule)
1967 {
1968         struct selinux_audit_rule *tmprule;
1969         struct role_datum *roledatum;
1970         struct type_datum *typedatum;
1971         struct user_datum *userdatum;
1972         int rc = 0;
1973
1974         *rule = NULL;
1975
1976         if (!ss_initialized)
1977                 return -ENOTSUPP;
1978
1979         switch (field) {
1980         case AUDIT_SUBJ_USER:
1981         case AUDIT_SUBJ_ROLE:
1982         case AUDIT_SUBJ_TYPE:
1983         case AUDIT_OBJ_USER:
1984         case AUDIT_OBJ_ROLE:
1985         case AUDIT_OBJ_TYPE:
1986                 /* only 'equals' and 'not equals' fit user, role, and type */
1987                 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
1988                         return -EINVAL;
1989                 break;
1990         case AUDIT_SUBJ_SEN:
1991         case AUDIT_SUBJ_CLR:
1992         case AUDIT_OBJ_LEV_LOW:
1993         case AUDIT_OBJ_LEV_HIGH:
1994                 /* we do not allow a range, indicated by the presense of '-' */
1995                 if (strchr(rulestr, '-'))
1996                         return -EINVAL;
1997                 break;
1998         default:
1999                 /* only the above fields are valid */
2000                 return -EINVAL;
2001         }
2002
2003         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2004         if (!tmprule)
2005                 return -ENOMEM;
2006
2007         context_init(&tmprule->au_ctxt);
2008
2009         POLICY_RDLOCK;
2010
2011         tmprule->au_seqno = latest_granting;
2012
2013         switch (field) {
2014         case AUDIT_SUBJ_USER:
2015         case AUDIT_OBJ_USER:
2016                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2017                 if (!userdatum)
2018                         rc = -EINVAL;
2019                 else
2020                         tmprule->au_ctxt.user = userdatum->value;
2021                 break;
2022         case AUDIT_SUBJ_ROLE:
2023         case AUDIT_OBJ_ROLE:
2024                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2025                 if (!roledatum)
2026                         rc = -EINVAL;
2027                 else
2028                         tmprule->au_ctxt.role = roledatum->value;
2029                 break;
2030         case AUDIT_SUBJ_TYPE:
2031         case AUDIT_OBJ_TYPE:
2032                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2033                 if (!typedatum)
2034                         rc = -EINVAL;
2035                 else
2036                         tmprule->au_ctxt.type = typedatum->value;
2037                 break;
2038         case AUDIT_SUBJ_SEN:
2039         case AUDIT_SUBJ_CLR:
2040         case AUDIT_OBJ_LEV_LOW:
2041         case AUDIT_OBJ_LEV_HIGH:
2042                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2043                 break;
2044         }
2045
2046         POLICY_RDUNLOCK;
2047
2048         if (rc) {
2049                 selinux_audit_rule_free(tmprule);
2050                 tmprule = NULL;
2051         }
2052
2053         *rule = tmprule;
2054
2055         return rc;
2056 }
2057
2058 int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
2059                              struct selinux_audit_rule *rule,
2060                              struct audit_context *actx)
2061 {
2062         struct context *ctxt;
2063         struct mls_level *level;
2064         int match = 0;
2065
2066         if (!rule) {
2067                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2068                           "selinux_audit_rule_match: missing rule\n");
2069                 return -ENOENT;
2070         }
2071
2072         POLICY_RDLOCK;
2073
2074         if (rule->au_seqno < latest_granting) {
2075                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2076                           "selinux_audit_rule_match: stale rule\n");
2077                 match = -ESTALE;
2078                 goto out;
2079         }
2080
2081         ctxt = sidtab_search(&sidtab, sid);
2082         if (!ctxt) {
2083                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2084                           "selinux_audit_rule_match: unrecognized SID %d\n",
2085                           sid);
2086                 match = -ENOENT;
2087                 goto out;
2088         }
2089
2090         /* a field/op pair that is not caught here will simply fall through
2091            without a match */
2092         switch (field) {
2093         case AUDIT_SUBJ_USER:
2094         case AUDIT_OBJ_USER:
2095                 switch (op) {
2096                 case AUDIT_EQUAL:
2097                         match = (ctxt->user == rule->au_ctxt.user);
2098                         break;
2099                 case AUDIT_NOT_EQUAL:
2100                         match = (ctxt->user != rule->au_ctxt.user);
2101                         break;
2102                 }
2103                 break;
2104         case AUDIT_SUBJ_ROLE:
2105         case AUDIT_OBJ_ROLE:
2106                 switch (op) {
2107                 case AUDIT_EQUAL:
2108                         match = (ctxt->role == rule->au_ctxt.role);
2109                         break;
2110                 case AUDIT_NOT_EQUAL:
2111                         match = (ctxt->role != rule->au_ctxt.role);
2112                         break;
2113                 }
2114                 break;
2115         case AUDIT_SUBJ_TYPE:
2116         case AUDIT_OBJ_TYPE:
2117                 switch (op) {
2118                 case AUDIT_EQUAL:
2119                         match = (ctxt->type == rule->au_ctxt.type);
2120                         break;
2121                 case AUDIT_NOT_EQUAL:
2122                         match = (ctxt->type != rule->au_ctxt.type);
2123                         break;
2124                 }
2125                 break;
2126         case AUDIT_SUBJ_SEN:
2127         case AUDIT_SUBJ_CLR:
2128         case AUDIT_OBJ_LEV_LOW:
2129         case AUDIT_OBJ_LEV_HIGH:
2130                 level = ((field == AUDIT_SUBJ_SEN ||
2131                           field == AUDIT_OBJ_LEV_LOW) ?
2132                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2133                 switch (op) {
2134                 case AUDIT_EQUAL:
2135                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2136                                              level);
2137                         break;
2138                 case AUDIT_NOT_EQUAL:
2139                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2140                                               level);
2141                         break;
2142                 case AUDIT_LESS_THAN:
2143                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2144                                                level) &&
2145                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2146                                                level));
2147                         break;
2148                 case AUDIT_LESS_THAN_OR_EQUAL:
2149                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2150                                               level);
2151                         break;
2152                 case AUDIT_GREATER_THAN:
2153                         match = (mls_level_dom(level,
2154                                               &rule->au_ctxt.range.level[0]) &&
2155                                  !mls_level_eq(level,
2156                                                &rule->au_ctxt.range.level[0]));
2157                         break;
2158                 case AUDIT_GREATER_THAN_OR_EQUAL:
2159                         match = mls_level_dom(level,
2160                                               &rule->au_ctxt.range.level[0]);
2161                         break;
2162                 }
2163         }
2164
2165 out:
2166         POLICY_RDUNLOCK;
2167         return match;
2168 }
2169
2170 static int (*aurule_callback)(void) = NULL;
2171
2172 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2173                                u16 class, u32 perms, u32 *retained)
2174 {
2175         int err = 0;
2176
2177         if (event == AVC_CALLBACK_RESET && aurule_callback)
2178                 err = aurule_callback();
2179         return err;
2180 }
2181
2182 static int __init aurule_init(void)
2183 {
2184         int err;
2185
2186         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2187                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2188         if (err)
2189                 panic("avc_add_callback() failed, error %d\n", err);
2190
2191         return err;
2192 }
2193 __initcall(aurule_init);
2194
2195 void selinux_audit_set_callback(int (*callback)(void))
2196 {
2197         aurule_callback = callback;
2198 }
2199
2200 #ifdef CONFIG_NETLABEL
2201 /*
2202  * NetLabel cache structure
2203  */
2204 #define NETLBL_CACHE(x)           ((struct selinux_netlbl_cache *)(x))
2205 #define NETLBL_CACHE_T_NONE       0
2206 #define NETLBL_CACHE_T_SID        1
2207 #define NETLBL_CACHE_T_MLS        2
2208 struct selinux_netlbl_cache {
2209         u32 type;
2210         union {
2211                 u32 sid;
2212                 struct mls_range mls_label;
2213         } data;
2214 };
2215
2216 /**
2217  * security_netlbl_cache_free - Free the NetLabel cached data
2218  * @data: the data to free
2219  *
2220  * Description:
2221  * This function is intended to be used as the free() callback inside the
2222  * netlbl_lsm_cache structure.
2223  *
2224  */
2225 static void security_netlbl_cache_free(const void *data)
2226 {
2227         struct selinux_netlbl_cache *cache;
2228
2229         if (data == NULL)
2230                 return;
2231
2232         cache = NETLBL_CACHE(data);
2233         switch (cache->type) {
2234         case NETLBL_CACHE_T_MLS:
2235                 ebitmap_destroy(&cache->data.mls_label.level[0].cat);
2236                 break;
2237         }
2238         kfree(data);
2239 }
2240
2241 /**
2242  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2243  * @secattr: the NetLabel packet security attributes
2244  * @ctx: the SELinux context
2245  *
2246  * Description:
2247  * Attempt to cache the context in @ctx, which was derived from the packet in
2248  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2249  * already been initialized.
2250  *
2251  */
2252 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2253                                       struct context *ctx)
2254 {
2255         struct selinux_netlbl_cache *cache = NULL;
2256
2257         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2258         if (secattr->cache == NULL)
2259                 return;
2260
2261         cache = kzalloc(sizeof(*cache), GFP_ATOMIC);
2262         if (cache == NULL)
2263                 return;
2264
2265         cache->type = NETLBL_CACHE_T_MLS;
2266         if (ebitmap_cpy(&cache->data.mls_label.level[0].cat,
2267                         &ctx->range.level[0].cat) != 0)
2268                 return;
2269         cache->data.mls_label.level[1].cat.highbit =
2270                 cache->data.mls_label.level[0].cat.highbit;
2271         cache->data.mls_label.level[1].cat.node =
2272                 cache->data.mls_label.level[0].cat.node;
2273         cache->data.mls_label.level[0].sens = ctx->range.level[0].sens;
2274         cache->data.mls_label.level[1].sens = ctx->range.level[0].sens;
2275
2276         secattr->cache->free = security_netlbl_cache_free;
2277         secattr->cache->data = (void *)cache;
2278         secattr->flags |= NETLBL_SECATTR_CACHE;
2279 }
2280
2281 /**
2282  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2283  * @secattr: the NetLabel packet security attributes
2284  * @base_sid: the SELinux SID to use as a context for MLS only attributes
2285  * @sid: the SELinux SID
2286  *
2287  * Description:
2288  * Convert the given NetLabel security attributes in @secattr into a
2289  * SELinux SID.  If the @secattr field does not contain a full SELinux
2290  * SID/context then use the context in @base_sid as the foundation.  If
2291  * possibile the 'cache' field of @secattr is set and the CACHE flag is set;
2292  * this is to allow the @secattr to be used by NetLabel to cache the secattr to
2293  * SID conversion for future lookups.  Returns zero on success, negative
2294  * values on failure.
2295  *
2296  */
2297 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2298                                    u32 base_sid,
2299                                    u32 *sid)
2300 {
2301         int rc = -EIDRM;
2302         struct context *ctx;
2303         struct context ctx_new;
2304         struct selinux_netlbl_cache *cache;
2305
2306         if (!ss_initialized) {
2307                 *sid = SECSID_NULL;
2308                 return 0;
2309         }
2310
2311         POLICY_RDLOCK;
2312
2313         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2314                 cache = NETLBL_CACHE(secattr->cache->data);
2315                 switch (cache->type) {
2316                 case NETLBL_CACHE_T_SID:
2317                         *sid = cache->data.sid;
2318                         rc = 0;
2319                         break;
2320                 case NETLBL_CACHE_T_MLS:
2321                         ctx = sidtab_search(&sidtab, base_sid);
2322                         if (ctx == NULL)
2323                                 goto netlbl_secattr_to_sid_return;
2324
2325                         ctx_new.user = ctx->user;
2326                         ctx_new.role = ctx->role;
2327                         ctx_new.type = ctx->type;
2328                         ctx_new.range.level[0].sens =
2329                                 cache->data.mls_label.level[0].sens;
2330                         ctx_new.range.level[0].cat.highbit =
2331                                 cache->data.mls_label.level[0].cat.highbit;
2332                         ctx_new.range.level[0].cat.node =
2333                                 cache->data.mls_label.level[0].cat.node;
2334                         ctx_new.range.level[1].sens =
2335                                 cache->data.mls_label.level[1].sens;
2336                         ctx_new.range.level[1].cat.highbit =
2337                                 cache->data.mls_label.level[1].cat.highbit;
2338                         ctx_new.range.level[1].cat.node =
2339                                 cache->data.mls_label.level[1].cat.node;
2340
2341                         rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2342                         break;
2343                 default:
2344                         goto netlbl_secattr_to_sid_return;
2345                 }
2346         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2347                 ctx = sidtab_search(&sidtab, base_sid);
2348                 if (ctx == NULL)
2349                         goto netlbl_secattr_to_sid_return;
2350
2351                 ctx_new.user = ctx->user;
2352                 ctx_new.role = ctx->role;
2353                 ctx_new.type = ctx->type;
2354                 mls_import_netlbl_lvl(&ctx_new, secattr);
2355                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2356                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2357                                                   secattr->mls_cat) != 0)
2358                                 goto netlbl_secattr_to_sid_return;
2359                         ctx_new.range.level[1].cat.highbit =
2360                                 ctx_new.range.level[0].cat.highbit;
2361                         ctx_new.range.level[1].cat.node =
2362                                 ctx_new.range.level[0].cat.node;
2363                 } else {
2364                         ebitmap_init(&ctx_new.range.level[0].cat);
2365                         ebitmap_init(&ctx_new.range.level[1].cat);
2366                 }
2367                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2368                         goto netlbl_secattr_to_sid_return_cleanup;
2369
2370                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2371                 if (rc != 0)
2372                         goto netlbl_secattr_to_sid_return_cleanup;
2373
2374                 security_netlbl_cache_add(secattr, &ctx_new);
2375
2376                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2377         } else {
2378                 *sid = SECSID_NULL;
2379                 rc = 0;
2380         }
2381
2382 netlbl_secattr_to_sid_return:
2383         POLICY_RDUNLOCK;
2384         return rc;
2385 netlbl_secattr_to_sid_return_cleanup:
2386         ebitmap_destroy(&ctx_new.range.level[0].cat);
2387         goto netlbl_secattr_to_sid_return;
2388 }
2389
2390 /**
2391  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2392  * @sid: the SELinux SID
2393  * @secattr: the NetLabel packet security attributes
2394  *
2395  * Description:
2396  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2397  * Returns zero on success, negative values on failure.
2398  *
2399  */
2400 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2401 {
2402         int rc = -ENOENT;
2403         struct context *ctx;
2404
2405         netlbl_secattr_init(secattr);
2406
2407         if (!ss_initialized)
2408                 return 0;
2409
2410         POLICY_RDLOCK;
2411         ctx = sidtab_search(&sidtab, sid);
2412         if (ctx == NULL)
2413                 goto netlbl_sid_to_secattr_failure;
2414         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2415                                   GFP_ATOMIC);
2416         secattr->flags |= NETLBL_SECATTR_DOMAIN;
2417         mls_export_netlbl_lvl(ctx, secattr);
2418         rc = mls_export_netlbl_cat(ctx, secattr);
2419         if (rc != 0)
2420                 goto netlbl_sid_to_secattr_failure;
2421         POLICY_RDUNLOCK;
2422
2423         return 0;
2424
2425 netlbl_sid_to_secattr_failure:
2426         POLICY_RDUNLOCK;
2427         netlbl_secattr_destroy(secattr);
2428         return rc;
2429 }
2430 #endif /* CONFIG_NETLABEL */