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