git.oblomov.eu Git - linux-2.6/blob - security/selinux/ss/services.c

   1 /*
   2  * Implementation of the security services.
   3  *
   4  * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
   5  *           James Morris <jmorris@redhat.com>
   6  *
   7  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
   8  *
   9  *      Support for enhanced MLS infrastructure.
  10  *      Support for context based audit filters.
  11  *
  12  * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
  13  *
  14  *      Added conditional policy language extensions
  15  *
  16  * Updated: Hewlett-Packard <paul.moore@hp.com>
  17  *
  18  *      Added support for NetLabel
  19  *
  20  * Updated: Chad Sellers <csellers@tresys.com>
  21  *
  22  *  Added validation of kernel classes and permissions
  23  *
  24  * Copyright (C) 2006 Hewlett-Packard Development Company, L.P.
  25  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
  26  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
  27  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
  28  *      This program is free software; you can redistribute it and/or modify
  29  *      it under the terms of the GNU General Public License as published by
  30  *      the Free Software Foundation, version 2.
  31  */
  32 #include <linux/kernel.h>
  33 #include <linux/slab.h>
  34 #include <linux/string.h>
  35 #include <linux/spinlock.h>
  36 #include <linux/rcupdate.h>
  37 #include <linux/errno.h>
  38 #include <linux/in.h>
  39 #include <linux/sched.h>
  40 #include <linux/audit.h>
  41 #include <linux/mutex.h>
  42 #include <net/netlabel.h>
  43
  44 #include "flask.h"
  45 #include "avc.h"
  46 #include "avc_ss.h"
  47 #include "security.h"
  48 #include "context.h"
  49 #include "policydb.h"
  50 #include "sidtab.h"
  51 #include "services.h"
  52 #include "conditional.h"
  53 #include "mls.h"
  54 #include "objsec.h"
  55 #include "netlabel.h"
  56 #include "xfrm.h"
  57 #include "ebitmap.h"
  58
  59 extern void selnl_notify_policyload(u32 seqno);
  60 unsigned int policydb_loaded_version;
  61
  62 /*
  63  * This is declared in avc.c
  64  */
  65 extern const struct selinux_class_perm selinux_class_perm;
  66
  67 static DEFINE_RWLOCK(policy_rwlock);
  68 #define POLICY_RDLOCK read_lock(&policy_rwlock)
  69 #define POLICY_WRLOCK write_lock_irq(&policy_rwlock)
  70 #define POLICY_RDUNLOCK read_unlock(&policy_rwlock)
  71 #define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock)
  72
  73 static DEFINE_MUTEX(load_mutex);
  74 #define LOAD_LOCK mutex_lock(&load_mutex)
  75 #define LOAD_UNLOCK mutex_unlock(&load_mutex)
  76
  77 static struct sidtab sidtab;
  78 struct policydb policydb;
  79 int ss_initialized = 0;
  80
  81 /*
  82  * The largest sequence number that has been used when
  83  * providing an access decision to the access vector cache.
  84  * The sequence number only changes when a policy change
  85  * occurs.
  86  */
  87 static u32 latest_granting = 0;
  88
  89 /* Forward declaration. */
  90 static int context_struct_to_string(struct context *context, char **scontext,
  91                                     u32 *scontext_len);
  92
  93 /*
  94  * Return the boolean value of a constraint expression
  95  * when it is applied to the specified source and target
  96  * security contexts.
  97  *
  98  * xcontext is a special beast...  It is used by the validatetrans rules
  99  * only.  For these rules, scontext is the context before the transition,
 100  * tcontext is the context after the transition, and xcontext is the context
 101  * of the process performing the transition.  All other callers of
 102  * constraint_expr_eval should pass in NULL for xcontext.
 103  */
 104 static int constraint_expr_eval(struct context *scontext,
 105                                 struct context *tcontext,
 106                                 struct context *xcontext,
 107                                 struct constraint_expr *cexpr)
 108 {
 109         u32 val1, val2;
 110         struct context *c;
 111         struct role_datum *r1, *r2;
 112         struct mls_level *l1, *l2;
 113         struct constraint_expr *e;
 114         int s[CEXPR_MAXDEPTH];
 115         int sp = -1;
 116
 117         for (e = cexpr; e; e = e->next) {
 118                 switch (e->expr_type) {
 119                 case CEXPR_NOT:
 120                         BUG_ON(sp < 0);
 121                         s[sp] = !s[sp];
 122                         break;
 123                 case CEXPR_AND:
 124                         BUG_ON(sp < 1);
 125                         sp--;
 126                         s[sp] &= s[sp+1];
 127                         break;
 128                 case CEXPR_OR:
 129                         BUG_ON(sp < 1);
 130                         sp--;
 131                         s[sp] |= s[sp+1];
 132                         break;
 133                 case CEXPR_ATTR:
 134                         if (sp == (CEXPR_MAXDEPTH-1))
 135                                 return 0;
 136                         switch (e->attr) {
 137                         case CEXPR_USER:
 138                                 val1 = scontext->user;
 139                                 val2 = tcontext->user;
 140                                 break;
 141                         case CEXPR_TYPE:
 142                                 val1 = scontext->type;
 143                                 val2 = tcontext->type;
 144                                 break;
 145                         case CEXPR_ROLE:
 146                                 val1 = scontext->role;
 147                                 val2 = tcontext->role;
 148                                 r1 = policydb.role_val_to_struct[val1 - 1];
 149                                 r2 = policydb.role_val_to_struct[val2 - 1];
 150                                 switch (e->op) {
 151                                 case CEXPR_DOM:
 152                                         s[++sp] = ebitmap_get_bit(&r1->dominates,
 153                                                                   val2 - 1);
 154                                         continue;
 155                                 case CEXPR_DOMBY:
 156                                         s[++sp] = ebitmap_get_bit(&r2->dominates,
 157                                                                   val1 - 1);
 158                                         continue;
 159                                 case CEXPR_INCOMP:
 160                                         s[++sp] = ( !ebitmap_get_bit(&r1->dominates,
 161                                                                      val2 - 1) &&
 162                                                     !ebitmap_get_bit(&r2->dominates,
 163                                                                      val1 - 1) );
 164                                         continue;
 165                                 default:
 166                                         break;
 167                                 }
 168                                 break;
 169                         case CEXPR_L1L2:
 170                                 l1 = &(scontext->range.level[0]);
 171                                 l2 = &(tcontext->range.level[0]);
 172                                 goto mls_ops;
 173                         case CEXPR_L1H2:
 174                                 l1 = &(scontext->range.level[0]);
 175                                 l2 = &(tcontext->range.level[1]);
 176                                 goto mls_ops;
 177                         case CEXPR_H1L2:
 178                                 l1 = &(scontext->range.level[1]);
 179                                 l2 = &(tcontext->range.level[0]);
 180                                 goto mls_ops;
 181                         case CEXPR_H1H2:
 182                                 l1 = &(scontext->range.level[1]);
 183                                 l2 = &(tcontext->range.level[1]);
 184                                 goto mls_ops;
 185                         case CEXPR_L1H1:
 186                                 l1 = &(scontext->range.level[0]);
 187                                 l2 = &(scontext->range.level[1]);
 188                                 goto mls_ops;
 189                         case CEXPR_L2H2:
 190                                 l1 = &(tcontext->range.level[0]);
 191                                 l2 = &(tcontext->range.level[1]);
 192                                 goto mls_ops;
 193 mls_ops:
 194                         switch (e->op) {
 195                         case CEXPR_EQ:
 196                                 s[++sp] = mls_level_eq(l1, l2);
 197                                 continue;
 198                         case CEXPR_NEQ:
 199                                 s[++sp] = !mls_level_eq(l1, l2);
 200                                 continue;
 201                         case CEXPR_DOM:
 202                                 s[++sp] = mls_level_dom(l1, l2);
 203                                 continue;
 204                         case CEXPR_DOMBY:
 205                                 s[++sp] = mls_level_dom(l2, l1);
 206                                 continue;
 207                         case CEXPR_INCOMP:
 208                                 s[++sp] = mls_level_incomp(l2, l1);
 209                                 continue;
 210                         default:
 211                                 BUG();
 212                                 return 0;
 213                         }
 214                         break;
 215                         default:
 216                                 BUG();
 217                                 return 0;
 218                         }
 219
 220                         switch (e->op) {
 221                         case CEXPR_EQ:
 222                                 s[++sp] = (val1 == val2);
 223                                 break;
 224                         case CEXPR_NEQ:
 225                                 s[++sp] = (val1 != val2);
 226                                 break;
 227                         default:
 228                                 BUG();
 229                                 return 0;
 230                         }
 231                         break;
 232                 case CEXPR_NAMES:
 233                         if (sp == (CEXPR_MAXDEPTH-1))
 234                                 return 0;
 235                         c = scontext;
 236                         if (e->attr & CEXPR_TARGET)
 237                                 c = tcontext;
 238                         else if (e->attr & CEXPR_XTARGET) {
 239                                 c = xcontext;
 240                                 if (!c) {
 241                                         BUG();
 242                                         return 0;
 243                                 }
 244                         }
 245                         if (e->attr & CEXPR_USER)
 246                                 val1 = c->user;
 247                         else if (e->attr & CEXPR_ROLE)
 248                                 val1 = c->role;
 249                         else if (e->attr & CEXPR_TYPE)
 250                                 val1 = c->type;
 251                         else {
 252                                 BUG();
 253                                 return 0;
 254                         }
 255
 256                         switch (e->op) {
 257                         case CEXPR_EQ:
 258                                 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
 259                                 break;
 260                         case CEXPR_NEQ:
 261                                 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
 262                                 break;
 263                         default:
 264                                 BUG();
 265                                 return 0;
 266                         }
 267                         break;
 268                 default:
 269                         BUG();
 270                         return 0;
 271                 }
 272         }
 273
 274         BUG_ON(sp != 0);
 275         return s[0];
 276 }
 277
 278 /*
 279  * Compute access vectors based on a context structure pair for
 280  * the permissions in a particular class.
 281  */
 282 static int context_struct_compute_av(struct context *scontext,
 283                                      struct context *tcontext,
 284                                      u16 tclass,
 285                                      u32 requested,
 286                                      struct av_decision *avd)
 287 {
 288         struct constraint_node *constraint;
 289         struct role_allow *ra;
 290         struct avtab_key avkey;
 291         struct avtab_node *node;
 292         struct class_datum *tclass_datum;
 293         struct ebitmap *sattr, *tattr;
 294         struct ebitmap_node *snode, *tnode;
 295         unsigned int i, j;
 296
 297         /*
 298          * Remap extended Netlink classes for old policy versions.
 299          * Do this here rather than socket_type_to_security_class()
 300          * in case a newer policy version is loaded, allowing sockets
 301          * to remain in the correct class.
 302          */
 303         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 304                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 305                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 306                         tclass = SECCLASS_NETLINK_SOCKET;
 307
 308         if (!tclass || tclass > policydb.p_classes.nprim) {
 309                 printk(KERN_ERR "security_compute_av:  unrecognized class %d\n",
 310                        tclass);
 311                 return -EINVAL;
 312         }
 313         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 314
 315         /*
 316          * Initialize the access vectors to the default values.
 317          */
 318         avd->allowed = 0;
 319         avd->decided = 0xffffffff;
 320         avd->auditallow = 0;
 321         avd->auditdeny = 0xffffffff;
 322         avd->seqno = latest_granting;
 323
 324         /*
 325          * If a specific type enforcement rule was defined for
 326          * this permission check, then use it.
 327          */
 328         avkey.target_class = tclass;
 329         avkey.specified = AVTAB_AV;
 330         sattr = &policydb.type_attr_map[scontext->type - 1];
 331         tattr = &policydb.type_attr_map[tcontext->type - 1];
 332         ebitmap_for_each_bit(sattr, snode, i) {
 333                 if (!ebitmap_node_get_bit(snode, i))
 334                         continue;
 335                 ebitmap_for_each_bit(tattr, tnode, j) {
 336                         if (!ebitmap_node_get_bit(tnode, j))
 337                                 continue;
 338                         avkey.source_type = i + 1;
 339                         avkey.target_type = j + 1;
 340                         for (node = avtab_search_node(&policydb.te_avtab, &avkey);
 341                              node != NULL;
 342                              node = avtab_search_node_next(node, avkey.specified)) {
 343                                 if (node->key.specified == AVTAB_ALLOWED)
 344                                         avd->allowed |= node->datum.data;
 345                                 else if (node->key.specified == AVTAB_AUDITALLOW)
 346                                         avd->auditallow |= node->datum.data;
 347                                 else if (node->key.specified == AVTAB_AUDITDENY)
 348                                         avd->auditdeny &= node->datum.data;
 349                         }
 350
 351                         /* Check conditional av table for additional permissions */
 352                         cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
 353
 354                 }
 355         }
 356
 357         /*
 358          * Remove any permissions prohibited by a constraint (this includes
 359          * the MLS policy).
 360          */
 361         constraint = tclass_datum->constraints;
 362         while (constraint) {
 363                 if ((constraint->permissions & (avd->allowed)) &&
 364                     !constraint_expr_eval(scontext, tcontext, NULL,
 365                                           constraint->expr)) {
 366                         avd->allowed = (avd->allowed) & ~(constraint->permissions);
 367                 }
 368                 constraint = constraint->next;
 369         }
 370
 371         /*
 372          * If checking process transition permission and the
 373          * role is changing, then check the (current_role, new_role)
 374          * pair.
 375          */
 376         if (tclass == SECCLASS_PROCESS &&
 377             (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
 378             scontext->role != tcontext->role) {
 379                 for (ra = policydb.role_allow; ra; ra = ra->next) {
 380                         if (scontext->role == ra->role &&
 381                             tcontext->role == ra->new_role)
 382                                 break;
 383                 }
 384                 if (!ra)
 385                         avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION |
 386                                                         PROCESS__DYNTRANSITION);
 387         }
 388
 389         return 0;
 390 }
 391
 392 static int security_validtrans_handle_fail(struct context *ocontext,
 393                                            struct context *ncontext,
 394                                            struct context *tcontext,
 395                                            u16 tclass)
 396 {
 397         char *o = NULL, *n = NULL, *t = NULL;
 398         u32 olen, nlen, tlen;
 399
 400         if (context_struct_to_string(ocontext, &o, &olen) < 0)
 401                 goto out;
 402         if (context_struct_to_string(ncontext, &n, &nlen) < 0)
 403                 goto out;
 404         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 405                 goto out;
 406         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 407                   "security_validate_transition:  denied for"
 408                   " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
 409                   o, n, t, policydb.p_class_val_to_name[tclass-1]);
 410 out:
 411         kfree(o);
 412         kfree(n);
 413         kfree(t);
 414
 415         if (!selinux_enforcing)
 416                 return 0;
 417         return -EPERM;
 418 }
 419
 420 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
 421                                  u16 tclass)
 422 {
 423         struct context *ocontext;
 424         struct context *ncontext;
 425         struct context *tcontext;
 426         struct class_datum *tclass_datum;
 427         struct constraint_node *constraint;
 428         int rc = 0;
 429
 430         if (!ss_initialized)
 431                 return 0;
 432
 433         POLICY_RDLOCK;
 434
 435         /*
 436          * Remap extended Netlink classes for old policy versions.
 437          * Do this here rather than socket_type_to_security_class()
 438          * in case a newer policy version is loaded, allowing sockets
 439          * to remain in the correct class.
 440          */
 441         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 442                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 443                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 444                         tclass = SECCLASS_NETLINK_SOCKET;
 445
 446         if (!tclass || tclass > policydb.p_classes.nprim) {
 447                 printk(KERN_ERR "security_validate_transition:  "
 448                        "unrecognized class %d\n", tclass);
 449                 rc = -EINVAL;
 450                 goto out;
 451         }
 452         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 453
 454         ocontext = sidtab_search(&sidtab, oldsid);
 455         if (!ocontext) {
 456                 printk(KERN_ERR "security_validate_transition: "
 457                        " unrecognized SID %d\n", oldsid);
 458                 rc = -EINVAL;
 459                 goto out;
 460         }
 461
 462         ncontext = sidtab_search(&sidtab, newsid);
 463         if (!ncontext) {
 464                 printk(KERN_ERR "security_validate_transition: "
 465                        " unrecognized SID %d\n", newsid);
 466                 rc = -EINVAL;
 467                 goto out;
 468         }
 469
 470         tcontext = sidtab_search(&sidtab, tasksid);
 471         if (!tcontext) {
 472                 printk(KERN_ERR "security_validate_transition: "
 473                        " unrecognized SID %d\n", tasksid);
 474                 rc = -EINVAL;
 475                 goto out;
 476         }
 477
 478         constraint = tclass_datum->validatetrans;
 479         while (constraint) {
 480                 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
 481                                           constraint->expr)) {
 482                         rc = security_validtrans_handle_fail(ocontext, ncontext,
 483                                                              tcontext, tclass);
 484                         goto out;
 485                 }
 486                 constraint = constraint->next;
 487         }
 488
 489 out:
 490         POLICY_RDUNLOCK;
 491         return rc;
 492 }
 493
 494 /**
 495  * security_compute_av - Compute access vector decisions.
 496  * @ssid: source security identifier
 497  * @tsid: target security identifier
 498  * @tclass: target security class
 499  * @requested: requested permissions
 500  * @avd: access vector decisions
 501  *
 502  * Compute a set of access vector decisions based on the
 503  * SID pair (@ssid, @tsid) for the permissions in @tclass.
 504  * Return -%EINVAL if any of the parameters are invalid or %0
 505  * if the access vector decisions were computed successfully.
 506  */
 507 int security_compute_av(u32 ssid,
 508                         u32 tsid,
 509                         u16 tclass,
 510                         u32 requested,
 511                         struct av_decision *avd)
 512 {
 513         struct context *scontext = NULL, *tcontext = NULL;
 514         int rc = 0;
 515
 516         if (!ss_initialized) {
 517                 avd->allowed = 0xffffffff;
 518                 avd->decided = 0xffffffff;
 519                 avd->auditallow = 0;
 520                 avd->auditdeny = 0xffffffff;
 521                 avd->seqno = latest_granting;
 522                 return 0;
 523         }
 524
 525         POLICY_RDLOCK;
 526
 527         scontext = sidtab_search(&sidtab, ssid);
 528         if (!scontext) {
 529                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
 530                        ssid);
 531                 rc = -EINVAL;
 532                 goto out;
 533         }
 534         tcontext = sidtab_search(&sidtab, tsid);
 535         if (!tcontext) {
 536                 printk(KERN_ERR "security_compute_av:  unrecognized SID %d\n",
 537                        tsid);
 538                 rc = -EINVAL;
 539                 goto out;
 540         }
 541
 542         rc = context_struct_compute_av(scontext, tcontext, tclass,
 543                                        requested, avd);
 544 out:
 545         POLICY_RDUNLOCK;
 546         return rc;
 547 }
 548
 549 /*
 550  * Write the security context string representation of
 551  * the context structure `context' into a dynamically
 552  * allocated string of the correct size.  Set `*scontext'
 553  * to point to this string and set `*scontext_len' to
 554  * the length of the string.
 555  */
 556 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
 557 {
 558         char *scontextp;
 559
 560         *scontext = NULL;
 561         *scontext_len = 0;
 562
 563         /* Compute the size of the context. */
 564         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
 565         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
 566         *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
 567         *scontext_len += mls_compute_context_len(context);
 568
 569         /* Allocate space for the context; caller must free this space. */
 570         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 571         if (!scontextp) {
 572                 return -ENOMEM;
 573         }
 574         *scontext = scontextp;
 575
 576         /*
 577          * Copy the user name, role name and type name into the context.
 578          */
 579         sprintf(scontextp, "%s:%s:%s",
 580                 policydb.p_user_val_to_name[context->user - 1],
 581                 policydb.p_role_val_to_name[context->role - 1],
 582                 policydb.p_type_val_to_name[context->type - 1]);
 583         scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
 584                      1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
 585                      1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
 586
 587         mls_sid_to_context(context, &scontextp);
 588
 589         *scontextp = 0;
 590
 591         return 0;
 592 }
 593
 594 #include "initial_sid_to_string.h"
 595
 596 const char *security_get_initial_sid_context(u32 sid)
 597 {
 598         if (unlikely(sid > SECINITSID_NUM))
 599                 return NULL;
 600         return initial_sid_to_string[sid];
 601 }
 602
 603 /**
 604  * security_sid_to_context - Obtain a context for a given SID.
 605  * @sid: security identifier, SID
 606  * @scontext: security context
 607  * @scontext_len: length in bytes
 608  *
 609  * Write the string representation of the context associated with @sid
 610  * into a dynamically allocated string of the correct size.  Set @scontext
 611  * to point to this string and set @scontext_len to the length of the string.
 612  */
 613 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
 614 {
 615         struct context *context;
 616         int rc = 0;
 617
 618         *scontext = NULL;
 619         *scontext_len  = 0;
 620
 621         if (!ss_initialized) {
 622                 if (sid <= SECINITSID_NUM) {
 623                         char *scontextp;
 624
 625                         *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
 626                         scontextp = kmalloc(*scontext_len,GFP_ATOMIC);
 627                         if (!scontextp) {
 628                                 rc = -ENOMEM;
 629                                 goto out;
 630                         }
 631                         strcpy(scontextp, initial_sid_to_string[sid]);
 632                         *scontext = scontextp;
 633                         goto out;
 634                 }
 635                 printk(KERN_ERR "security_sid_to_context:  called before initial "
 636                        "load_policy on unknown SID %d\n", sid);
 637                 rc = -EINVAL;
 638                 goto out;
 639         }
 640         POLICY_RDLOCK;
 641         context = sidtab_search(&sidtab, sid);
 642         if (!context) {
 643                 printk(KERN_ERR "security_sid_to_context:  unrecognized SID "
 644                        "%d\n", sid);
 645                 rc = -EINVAL;
 646                 goto out_unlock;
 647         }
 648         rc = context_struct_to_string(context, scontext, scontext_len);
 649 out_unlock:
 650         POLICY_RDUNLOCK;
 651 out:
 652         return rc;
 653
 654 }
 655
 656 static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
 657 {
 658         char *scontext2;
 659         struct context context;
 660         struct role_datum *role;
 661         struct type_datum *typdatum;
 662         struct user_datum *usrdatum;
 663         char *scontextp, *p, oldc;
 664         int rc = 0;
 665
 666         if (!ss_initialized) {
 667                 int i;
 668
 669                 for (i = 1; i < SECINITSID_NUM; i++) {
 670                         if (!strcmp(initial_sid_to_string[i], scontext)) {
 671                                 *sid = i;
 672                                 goto out;
 673                         }
 674                 }
 675                 *sid = SECINITSID_KERNEL;
 676                 goto out;
 677         }
 678         *sid = SECSID_NULL;
 679
 680         /* Copy the string so that we can modify the copy as we parse it.
 681            The string should already by null terminated, but we append a
 682            null suffix to the copy to avoid problems with the existing
 683            attr package, which doesn't view the null terminator as part
 684            of the attribute value. */
 685         scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
 686         if (!scontext2) {
 687                 rc = -ENOMEM;
 688                 goto out;
 689         }
 690         memcpy(scontext2, scontext, scontext_len);
 691         scontext2[scontext_len] = 0;
 692
 693         context_init(&context);
 694         *sid = SECSID_NULL;
 695
 696         POLICY_RDLOCK;
 697
 698         /* Parse the security context. */
 699
 700         rc = -EINVAL;
 701         scontextp = (char *) scontext2;
 702
 703         /* Extract the user. */
 704         p = scontextp;
 705         while (*p && *p != ':')
 706                 p++;
 707
 708         if (*p == 0)
 709                 goto out_unlock;
 710
 711         *p++ = 0;
 712
 713         usrdatum = hashtab_search(policydb.p_users.table, scontextp);
 714         if (!usrdatum)
 715                 goto out_unlock;
 716
 717         context.user = usrdatum->value;
 718
 719         /* Extract role. */
 720         scontextp = p;
 721         while (*p && *p != ':')
 722                 p++;
 723
 724         if (*p == 0)
 725                 goto out_unlock;
 726
 727         *p++ = 0;
 728
 729         role = hashtab_search(policydb.p_roles.table, scontextp);
 730         if (!role)
 731                 goto out_unlock;
 732         context.role = role->value;
 733
 734         /* Extract type. */
 735         scontextp = p;
 736         while (*p && *p != ':')
 737                 p++;
 738         oldc = *p;
 739         *p++ = 0;
 740
 741         typdatum = hashtab_search(policydb.p_types.table, scontextp);
 742         if (!typdatum)
 743                 goto out_unlock;
 744
 745         context.type = typdatum->value;
 746
 747         rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid);
 748         if (rc)
 749                 goto out_unlock;
 750
 751         if ((p - scontext2) < scontext_len) {
 752                 rc = -EINVAL;
 753                 goto out_unlock;
 754         }
 755
 756         /* Check the validity of the new context. */
 757         if (!policydb_context_isvalid(&policydb, &context)) {
 758                 rc = -EINVAL;
 759                 goto out_unlock;
 760         }
 761         /* Obtain the new sid. */
 762         rc = sidtab_context_to_sid(&sidtab, &context, sid);
 763 out_unlock:
 764         POLICY_RDUNLOCK;
 765         context_destroy(&context);
 766         kfree(scontext2);
 767 out:
 768         return rc;
 769 }
 770
 771 /**
 772  * security_context_to_sid - Obtain a SID for a given security context.
 773  * @scontext: security context
 774  * @scontext_len: length in bytes
 775  * @sid: security identifier, SID
 776  *
 777  * Obtains a SID associated with the security context that
 778  * has the string representation specified by @scontext.
 779  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 780  * memory is available, or 0 on success.
 781  */
 782 int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
 783 {
 784         return security_context_to_sid_core(scontext, scontext_len,
 785                                             sid, SECSID_NULL);
 786 }
 787
 788 /**
 789  * security_context_to_sid_default - Obtain a SID for a given security context,
 790  * falling back to specified default if needed.
 791  *
 792  * @scontext: security context
 793  * @scontext_len: length in bytes
 794  * @sid: security identifier, SID
 795  * @def_sid: default SID to assign on errror
 796  *
 797  * Obtains a SID associated with the security context that
 798  * has the string representation specified by @scontext.
 799  * The default SID is passed to the MLS layer to be used to allow
 800  * kernel labeling of the MLS field if the MLS field is not present
 801  * (for upgrading to MLS without full relabel).
 802  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
 803  * memory is available, or 0 on success.
 804  */
 805 int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
 806 {
 807         return security_context_to_sid_core(scontext, scontext_len,
 808                                             sid, def_sid);
 809 }
 810
 811 static int compute_sid_handle_invalid_context(
 812         struct context *scontext,
 813         struct context *tcontext,
 814         u16 tclass,
 815         struct context *newcontext)
 816 {
 817         char *s = NULL, *t = NULL, *n = NULL;
 818         u32 slen, tlen, nlen;
 819
 820         if (context_struct_to_string(scontext, &s, &slen) < 0)
 821                 goto out;
 822         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 823                 goto out;
 824         if (context_struct_to_string(newcontext, &n, &nlen) < 0)
 825                 goto out;
 826         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 827                   "security_compute_sid:  invalid context %s"
 828                   " for scontext=%s"
 829                   " tcontext=%s"
 830                   " tclass=%s",
 831                   n, s, t, policydb.p_class_val_to_name[tclass-1]);
 832 out:
 833         kfree(s);
 834         kfree(t);
 835         kfree(n);
 836         if (!selinux_enforcing)
 837                 return 0;
 838         return -EACCES;
 839 }
 840
 841 static int security_compute_sid(u32 ssid,
 842                                 u32 tsid,
 843                                 u16 tclass,
 844                                 u32 specified,
 845                                 u32 *out_sid)
 846 {
 847         struct context *scontext = NULL, *tcontext = NULL, newcontext;
 848         struct role_trans *roletr = NULL;
 849         struct avtab_key avkey;
 850         struct avtab_datum *avdatum;
 851         struct avtab_node *node;
 852         int rc = 0;
 853
 854         if (!ss_initialized) {
 855                 switch (tclass) {
 856                 case SECCLASS_PROCESS:
 857                         *out_sid = ssid;
 858                         break;
 859                 default:
 860                         *out_sid = tsid;
 861                         break;
 862                 }
 863                 goto out;
 864         }
 865
 866         context_init(&newcontext);
 867
 868         POLICY_RDLOCK;
 869
 870         scontext = sidtab_search(&sidtab, ssid);
 871         if (!scontext) {
 872                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
 873                        ssid);
 874                 rc = -EINVAL;
 875                 goto out_unlock;
 876         }
 877         tcontext = sidtab_search(&sidtab, tsid);
 878         if (!tcontext) {
 879                 printk(KERN_ERR "security_compute_sid:  unrecognized SID %d\n",
 880                        tsid);
 881                 rc = -EINVAL;
 882                 goto out_unlock;
 883         }
 884
 885         /* Set the user identity. */
 886         switch (specified) {
 887         case AVTAB_TRANSITION:
 888         case AVTAB_CHANGE:
 889                 /* Use the process user identity. */
 890                 newcontext.user = scontext->user;
 891                 break;
 892         case AVTAB_MEMBER:
 893                 /* Use the related object owner. */
 894                 newcontext.user = tcontext->user;
 895                 break;
 896         }
 897
 898         /* Set the role and type to default values. */
 899         switch (tclass) {
 900         case SECCLASS_PROCESS:
 901                 /* Use the current role and type of process. */
 902                 newcontext.role = scontext->role;
 903                 newcontext.type = scontext->type;
 904                 break;
 905         default:
 906                 /* Use the well-defined object role. */
 907                 newcontext.role = OBJECT_R_VAL;
 908                 /* Use the type of the related object. */
 909                 newcontext.type = tcontext->type;
 910         }
 911
 912         /* Look for a type transition/member/change rule. */
 913         avkey.source_type = scontext->type;
 914         avkey.target_type = tcontext->type;
 915         avkey.target_class = tclass;
 916         avkey.specified = specified;
 917         avdatum = avtab_search(&policydb.te_avtab, &avkey);
 918
 919         /* If no permanent rule, also check for enabled conditional rules */
 920         if(!avdatum) {
 921                 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
 922                 for (; node != NULL; node = avtab_search_node_next(node, specified)) {
 923                         if (node->key.specified & AVTAB_ENABLED) {
 924                                 avdatum = &node->datum;
 925                                 break;
 926                         }
 927                 }
 928         }
 929
 930         if (avdatum) {
 931                 /* Use the type from the type transition/member/change rule. */
 932                 newcontext.type = avdatum->data;
 933         }
 934
 935         /* Check for class-specific changes. */
 936         switch (tclass) {
 937         case SECCLASS_PROCESS:
 938                 if (specified & AVTAB_TRANSITION) {
 939                         /* Look for a role transition rule. */
 940                         for (roletr = policydb.role_tr; roletr;
 941                              roletr = roletr->next) {
 942                                 if (roletr->role == scontext->role &&
 943                                     roletr->type == tcontext->type) {
 944                                         /* Use the role transition rule. */
 945                                         newcontext.role = roletr->new_role;
 946                                         break;
 947                                 }
 948                         }
 949                 }
 950                 break;
 951         default:
 952                 break;
 953         }
 954
 955         /* Set the MLS attributes.
 956            This is done last because it may allocate memory. */
 957         rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
 958         if (rc)
 959                 goto out_unlock;
 960
 961         /* Check the validity of the context. */
 962         if (!policydb_context_isvalid(&policydb, &newcontext)) {
 963                 rc = compute_sid_handle_invalid_context(scontext,
 964                                                         tcontext,
 965                                                         tclass,
 966                                                         &newcontext);
 967                 if (rc)
 968                         goto out_unlock;
 969         }
 970         /* Obtain the sid for the context. */
 971         rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
 972 out_unlock:
 973         POLICY_RDUNLOCK;
 974         context_destroy(&newcontext);
 975 out:
 976         return rc;
 977 }
 978
 979 /**
 980  * security_transition_sid - Compute the SID for a new subject/object.
 981  * @ssid: source security identifier
 982  * @tsid: target security identifier
 983  * @tclass: target security class
 984  * @out_sid: security identifier for new subject/object
 985  *
 986  * Compute a SID to use for labeling a new subject or object in the
 987  * class @tclass based on a SID pair (@ssid, @tsid).
 988  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
 989  * if insufficient memory is available, or %0 if the new SID was
 990  * computed successfully.
 991  */
 992 int security_transition_sid(u32 ssid,
 993                             u32 tsid,
 994                             u16 tclass,
 995                             u32 *out_sid)
 996 {
 997         return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
 998 }
 999
1000 /**
1001  * security_member_sid - Compute the SID for member selection.
1002  * @ssid: source security identifier
1003  * @tsid: target security identifier
1004  * @tclass: target security class
1005  * @out_sid: security identifier for selected member
1006  *
1007  * Compute a SID to use when selecting a member of a polyinstantiated
1008  * object of class @tclass based on a SID pair (@ssid, @tsid).
1009  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1010  * if insufficient memory is available, or %0 if the SID was
1011  * computed successfully.
1012  */
1013 int security_member_sid(u32 ssid,
1014                         u32 tsid,
1015                         u16 tclass,
1016                         u32 *out_sid)
1017 {
1018         return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
1019 }
1020
1021 /**
1022  * security_change_sid - Compute the SID for object relabeling.
1023  * @ssid: source security identifier
1024  * @tsid: target security identifier
1025  * @tclass: target security class
1026  * @out_sid: security identifier for selected member
1027  *
1028  * Compute a SID to use for relabeling an object of class @tclass
1029  * based on a SID pair (@ssid, @tsid).
1030  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1031  * if insufficient memory is available, or %0 if the SID was
1032  * computed successfully.
1033  */
1034 int security_change_sid(u32 ssid,
1035                         u32 tsid,
1036                         u16 tclass,
1037                         u32 *out_sid)
1038 {
1039         return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1040 }
1041
1042 /*
1043  * Verify that each kernel class that is defined in the
1044  * policy is correct
1045  */
1046 static int validate_classes(struct policydb *p)
1047 {
1048         int i, j;
1049         struct class_datum *cladatum;
1050         struct perm_datum *perdatum;
1051         u32 nprim, tmp, common_pts_len, perm_val, pol_val;
1052         u16 class_val;
1053         const struct selinux_class_perm *kdefs = &selinux_class_perm;
1054         const char *def_class, *def_perm, *pol_class;
1055         struct symtab *perms;
1056
1057         for (i = 1; i < kdefs->cts_len; i++) {
1058                 def_class = kdefs->class_to_string[i];
1059                 if (!def_class)
1060                         continue;
1061                 if (i > p->p_classes.nprim) {
1062                         printk(KERN_INFO
1063                                "security:  class %s not defined in policy\n",
1064                                def_class);
1065                         continue;
1066                 }
1067                 pol_class = p->p_class_val_to_name[i-1];
1068                 if (strcmp(pol_class, def_class)) {
1069                         printk(KERN_ERR
1070                                "security:  class %d is incorrect, found %s but should be %s\n",
1071                                i, pol_class, def_class);
1072                         return -EINVAL;
1073                 }
1074         }
1075         for (i = 0; i < kdefs->av_pts_len; i++) {
1076                 class_val = kdefs->av_perm_to_string[i].tclass;
1077                 perm_val = kdefs->av_perm_to_string[i].value;
1078                 def_perm = kdefs->av_perm_to_string[i].name;
1079                 if (class_val > p->p_classes.nprim)
1080                         continue;
1081                 pol_class = p->p_class_val_to_name[class_val-1];
1082                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1083                 BUG_ON(!cladatum);
1084                 perms = &cladatum->permissions;
1085                 nprim = 1 << (perms->nprim - 1);
1086                 if (perm_val > nprim) {
1087                         printk(KERN_INFO
1088                                "security:  permission %s in class %s not defined in policy\n",
1089                                def_perm, pol_class);
1090                         continue;
1091                 }
1092                 perdatum = hashtab_search(perms->table, def_perm);
1093                 if (perdatum == NULL) {
1094                         printk(KERN_ERR
1095                                "security:  permission %s in class %s not found in policy\n",
1096                                def_perm, pol_class);
1097                         return -EINVAL;
1098                 }
1099                 pol_val = 1 << (perdatum->value - 1);
1100                 if (pol_val != perm_val) {
1101                         printk(KERN_ERR
1102                                "security:  permission %s in class %s has incorrect value\n",
1103                                def_perm, pol_class);
1104                         return -EINVAL;
1105                 }
1106         }
1107         for (i = 0; i < kdefs->av_inherit_len; i++) {
1108                 class_val = kdefs->av_inherit[i].tclass;
1109                 if (class_val > p->p_classes.nprim)
1110                         continue;
1111                 pol_class = p->p_class_val_to_name[class_val-1];
1112                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1113                 BUG_ON(!cladatum);
1114                 if (!cladatum->comdatum) {
1115                         printk(KERN_ERR
1116                                "security:  class %s should have an inherits clause but does not\n",
1117                                pol_class);
1118                         return -EINVAL;
1119                 }
1120                 tmp = kdefs->av_inherit[i].common_base;
1121                 common_pts_len = 0;
1122                 while (!(tmp & 0x01)) {
1123                         common_pts_len++;
1124                         tmp >>= 1;
1125                 }
1126                 perms = &cladatum->comdatum->permissions;
1127                 for (j = 0; j < common_pts_len; j++) {
1128                         def_perm = kdefs->av_inherit[i].common_pts[j];
1129                         if (j >= perms->nprim) {
1130                                 printk(KERN_INFO
1131                                        "security:  permission %s in class %s not defined in policy\n",
1132                                        def_perm, pol_class);
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\n",
1139                                        def_perm, pol_class);
1140                                 return -EINVAL;
1141                         }
1142                         if (perdatum->value != j + 1) {
1143                                 printk(KERN_ERR
1144                                        "security:  permission %s in class %s has incorrect value\n",
1145                                        def_perm, pol_class);
1146                                 return -EINVAL;
1147                         }
1148                 }
1149         }
1150         return 0;
1151 }
1152
1153 /* Clone the SID into the new SID table. */
1154 static int clone_sid(u32 sid,
1155                      struct context *context,
1156                      void *arg)
1157 {
1158         struct sidtab *s = arg;
1159
1160         return sidtab_insert(s, sid, context);
1161 }
1162
1163 static inline int convert_context_handle_invalid_context(struct context *context)
1164 {
1165         int rc = 0;
1166
1167         if (selinux_enforcing) {
1168                 rc = -EINVAL;
1169         } else {
1170                 char *s;
1171                 u32 len;
1172
1173                 context_struct_to_string(context, &s, &len);
1174                 printk(KERN_ERR "security:  context %s is invalid\n", s);
1175                 kfree(s);
1176         }
1177         return rc;
1178 }
1179
1180 struct convert_context_args {
1181         struct policydb *oldp;
1182         struct policydb *newp;
1183 };
1184
1185 /*
1186  * Convert the values in the security context
1187  * structure `c' from the values specified
1188  * in the policy `p->oldp' to the values specified
1189  * in the policy `p->newp'.  Verify that the
1190  * context is valid under the new policy.
1191  */
1192 static int convert_context(u32 key,
1193                            struct context *c,
1194                            void *p)
1195 {
1196         struct convert_context_args *args;
1197         struct context oldc;
1198         struct role_datum *role;
1199         struct type_datum *typdatum;
1200         struct user_datum *usrdatum;
1201         char *s;
1202         u32 len;
1203         int rc;
1204
1205         args = p;
1206
1207         rc = context_cpy(&oldc, c);
1208         if (rc)
1209                 goto out;
1210
1211         rc = -EINVAL;
1212
1213         /* Convert the user. */
1214         usrdatum = hashtab_search(args->newp->p_users.table,
1215                                   args->oldp->p_user_val_to_name[c->user - 1]);
1216         if (!usrdatum) {
1217                 goto bad;
1218         }
1219         c->user = usrdatum->value;
1220
1221         /* Convert the role. */
1222         role = hashtab_search(args->newp->p_roles.table,
1223                               args->oldp->p_role_val_to_name[c->role - 1]);
1224         if (!role) {
1225                 goto bad;
1226         }
1227         c->role = role->value;
1228
1229         /* Convert the type. */
1230         typdatum = hashtab_search(args->newp->p_types.table,
1231                                   args->oldp->p_type_val_to_name[c->type - 1]);
1232         if (!typdatum) {
1233                 goto bad;
1234         }
1235         c->type = typdatum->value;
1236
1237         rc = mls_convert_context(args->oldp, args->newp, c);
1238         if (rc)
1239                 goto bad;
1240
1241         /* Check the validity of the new context. */
1242         if (!policydb_context_isvalid(args->newp, c)) {
1243                 rc = convert_context_handle_invalid_context(&oldc);
1244                 if (rc)
1245                         goto bad;
1246         }
1247
1248         context_destroy(&oldc);
1249 out:
1250         return rc;
1251 bad:
1252         context_struct_to_string(&oldc, &s, &len);
1253         context_destroy(&oldc);
1254         printk(KERN_ERR "security:  invalidating context %s\n", s);
1255         kfree(s);
1256         goto out;
1257 }
1258
1259 extern void selinux_complete_init(void);
1260 static int security_preserve_bools(struct policydb *p);
1261
1262 /**
1263  * security_load_policy - Load a security policy configuration.
1264  * @data: binary policy data
1265  * @len: length of data in bytes
1266  *
1267  * Load a new set of security policy configuration data,
1268  * validate it and convert the SID table as necessary.
1269  * This function will flush the access vector cache after
1270  * loading the new policy.
1271  */
1272 int security_load_policy(void *data, size_t len)
1273 {
1274         struct policydb oldpolicydb, newpolicydb;
1275         struct sidtab oldsidtab, newsidtab;
1276         struct convert_context_args args;
1277         u32 seqno;
1278         int rc = 0;
1279         struct policy_file file = { data, len }, *fp = &file;
1280
1281         LOAD_LOCK;
1282
1283         if (!ss_initialized) {
1284                 avtab_cache_init();
1285                 if (policydb_read(&policydb, fp)) {
1286                         LOAD_UNLOCK;
1287                         avtab_cache_destroy();
1288                         return -EINVAL;
1289                 }
1290                 if (policydb_load_isids(&policydb, &sidtab)) {
1291                         LOAD_UNLOCK;
1292                         policydb_destroy(&policydb);
1293                         avtab_cache_destroy();
1294                         return -EINVAL;
1295                 }
1296                 /* Verify that the kernel defined classes are correct. */
1297                 if (validate_classes(&policydb)) {
1298                         printk(KERN_ERR
1299                                "security:  the definition of a class is incorrect\n");
1300                         LOAD_UNLOCK;
1301                         sidtab_destroy(&sidtab);
1302                         policydb_destroy(&policydb);
1303                         avtab_cache_destroy();
1304                         return -EINVAL;
1305                 }
1306                 policydb_loaded_version = policydb.policyvers;
1307                 ss_initialized = 1;
1308                 seqno = ++latest_granting;
1309                 LOAD_UNLOCK;
1310                 selinux_complete_init();
1311                 avc_ss_reset(seqno);
1312                 selnl_notify_policyload(seqno);
1313                 selinux_netlbl_cache_invalidate();
1314                 selinux_xfrm_notify_policyload();
1315                 return 0;
1316         }
1317
1318 #if 0
1319         sidtab_hash_eval(&sidtab, "sids");
1320 #endif
1321
1322         if (policydb_read(&newpolicydb, fp)) {
1323                 LOAD_UNLOCK;
1324                 return -EINVAL;
1325         }
1326
1327         sidtab_init(&newsidtab);
1328
1329         /* Verify that the kernel defined classes are correct. */
1330         if (validate_classes(&newpolicydb)) {
1331                 printk(KERN_ERR
1332                        "security:  the definition of a class is incorrect\n");
1333                 rc = -EINVAL;
1334                 goto err;
1335         }
1336
1337         rc = security_preserve_bools(&newpolicydb);
1338         if (rc) {
1339                 printk(KERN_ERR "security:  unable to preserve booleans\n");
1340                 goto err;
1341         }
1342
1343         /* Clone the SID table. */
1344         sidtab_shutdown(&sidtab);
1345         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1346                 rc = -ENOMEM;
1347                 goto err;
1348         }
1349
1350         /* Convert the internal representations of contexts
1351            in the new SID table and remove invalid SIDs. */
1352         args.oldp = &policydb;
1353         args.newp = &newpolicydb;
1354         sidtab_map_remove_on_error(&newsidtab, convert_context, &args);
1355
1356         /* Save the old policydb and SID table to free later. */
1357         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1358         sidtab_set(&oldsidtab, &sidtab);
1359
1360         /* Install the new policydb and SID table. */
1361         POLICY_WRLOCK;
1362         memcpy(&policydb, &newpolicydb, sizeof policydb);
1363         sidtab_set(&sidtab, &newsidtab);
1364         seqno = ++latest_granting;
1365         policydb_loaded_version = policydb.policyvers;
1366         POLICY_WRUNLOCK;
1367         LOAD_UNLOCK;
1368
1369         /* Free the old policydb and SID table. */
1370         policydb_destroy(&oldpolicydb);
1371         sidtab_destroy(&oldsidtab);
1372
1373         avc_ss_reset(seqno);
1374         selnl_notify_policyload(seqno);
1375         selinux_netlbl_cache_invalidate();
1376         selinux_xfrm_notify_policyload();
1377
1378         return 0;
1379
1380 err:
1381         LOAD_UNLOCK;
1382         sidtab_destroy(&newsidtab);
1383         policydb_destroy(&newpolicydb);
1384         return rc;
1385
1386 }
1387
1388 /**
1389  * security_port_sid - Obtain the SID for a port.
1390  * @domain: communication domain aka address family
1391  * @type: socket type
1392  * @protocol: protocol number
1393  * @port: port number
1394  * @out_sid: security identifier
1395  */
1396 int security_port_sid(u16 domain,
1397                       u16 type,
1398                       u8 protocol,
1399                       u16 port,
1400                       u32 *out_sid)
1401 {
1402         struct ocontext *c;
1403         int rc = 0;
1404
1405         POLICY_RDLOCK;
1406
1407         c = policydb.ocontexts[OCON_PORT];
1408         while (c) {
1409                 if (c->u.port.protocol == protocol &&
1410                     c->u.port.low_port <= port &&
1411                     c->u.port.high_port >= port)
1412                         break;
1413                 c = c->next;
1414         }
1415
1416         if (c) {
1417                 if (!c->sid[0]) {
1418                         rc = sidtab_context_to_sid(&sidtab,
1419                                                    &c->context[0],
1420                                                    &c->sid[0]);
1421                         if (rc)
1422                                 goto out;
1423                 }
1424                 *out_sid = c->sid[0];
1425         } else {
1426                 *out_sid = SECINITSID_PORT;
1427         }
1428
1429 out:
1430         POLICY_RDUNLOCK;
1431         return rc;
1432 }
1433
1434 /**
1435  * security_netif_sid - Obtain the SID for a network interface.
1436  * @name: interface name
1437  * @if_sid: interface SID
1438  * @msg_sid: default SID for received packets
1439  */
1440 int security_netif_sid(char *name,
1441                        u32 *if_sid,
1442                        u32 *msg_sid)
1443 {
1444         int rc = 0;
1445         struct ocontext *c;
1446
1447         POLICY_RDLOCK;
1448
1449         c = policydb.ocontexts[OCON_NETIF];
1450         while (c) {
1451                 if (strcmp(name, c->u.name) == 0)
1452                         break;
1453                 c = c->next;
1454         }
1455
1456         if (c) {
1457                 if (!c->sid[0] || !c->sid[1]) {
1458                         rc = sidtab_context_to_sid(&sidtab,
1459                                                   &c->context[0],
1460                                                   &c->sid[0]);
1461                         if (rc)
1462                                 goto out;
1463                         rc = sidtab_context_to_sid(&sidtab,
1464                                                    &c->context[1],
1465                                                    &c->sid[1]);
1466                         if (rc)
1467                                 goto out;
1468                 }
1469                 *if_sid = c->sid[0];
1470                 *msg_sid = c->sid[1];
1471         } else {
1472                 *if_sid = SECINITSID_NETIF;
1473                 *msg_sid = SECINITSID_NETMSG;
1474         }
1475
1476 out:
1477         POLICY_RDUNLOCK;
1478         return rc;
1479 }
1480
1481 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1482 {
1483         int i, fail = 0;
1484
1485         for(i = 0; i < 4; i++)
1486                 if(addr[i] != (input[i] & mask[i])) {
1487                         fail = 1;
1488                         break;
1489                 }
1490
1491         return !fail;
1492 }
1493
1494 /**
1495  * security_node_sid - Obtain the SID for a node (host).
1496  * @domain: communication domain aka address family
1497  * @addrp: address
1498  * @addrlen: address length in bytes
1499  * @out_sid: security identifier
1500  */
1501 int security_node_sid(u16 domain,
1502                       void *addrp,
1503                       u32 addrlen,
1504                       u32 *out_sid)
1505 {
1506         int rc = 0;
1507         struct ocontext *c;
1508
1509         POLICY_RDLOCK;
1510
1511         switch (domain) {
1512         case AF_INET: {
1513                 u32 addr;
1514
1515                 if (addrlen != sizeof(u32)) {
1516                         rc = -EINVAL;
1517                         goto out;
1518                 }
1519
1520                 addr = *((u32 *)addrp);
1521
1522                 c = policydb.ocontexts[OCON_NODE];
1523                 while (c) {
1524                         if (c->u.node.addr == (addr & c->u.node.mask))
1525                                 break;
1526                         c = c->next;
1527                 }
1528                 break;
1529         }
1530
1531         case AF_INET6:
1532                 if (addrlen != sizeof(u64) * 2) {
1533                         rc = -EINVAL;
1534                         goto out;
1535                 }
1536                 c = policydb.ocontexts[OCON_NODE6];
1537                 while (c) {
1538                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1539                                                 c->u.node6.mask))
1540                                 break;
1541                         c = c->next;
1542                 }
1543                 break;
1544
1545         default:
1546                 *out_sid = SECINITSID_NODE;
1547                 goto out;
1548         }
1549
1550         if (c) {
1551                 if (!c->sid[0]) {
1552                         rc = sidtab_context_to_sid(&sidtab,
1553                                                    &c->context[0],
1554                                                    &c->sid[0]);
1555                         if (rc)
1556                                 goto out;
1557                 }
1558                 *out_sid = c->sid[0];
1559         } else {
1560                 *out_sid = SECINITSID_NODE;
1561         }
1562
1563 out:
1564         POLICY_RDUNLOCK;
1565         return rc;
1566 }
1567
1568 #define SIDS_NEL 25
1569
1570 /**
1571  * security_get_user_sids - Obtain reachable SIDs for a user.
1572  * @fromsid: starting SID
1573  * @username: username
1574  * @sids: array of reachable SIDs for user
1575  * @nel: number of elements in @sids
1576  *
1577  * Generate the set of SIDs for legal security contexts
1578  * for a given user that can be reached by @fromsid.
1579  * Set *@sids to point to a dynamically allocated
1580  * array containing the set of SIDs.  Set *@nel to the
1581  * number of elements in the array.
1582  */
1583
1584 int security_get_user_sids(u32 fromsid,
1585                            char *username,
1586                            u32 **sids,
1587                            u32 *nel)
1588 {
1589         struct context *fromcon, usercon;
1590         u32 *mysids, *mysids2, sid;
1591         u32 mynel = 0, maxnel = SIDS_NEL;
1592         struct user_datum *user;
1593         struct role_datum *role;
1594         struct av_decision avd;
1595         struct ebitmap_node *rnode, *tnode;
1596         int rc = 0, i, j;
1597
1598         if (!ss_initialized) {
1599                 *sids = NULL;
1600                 *nel = 0;
1601                 goto out;
1602         }
1603
1604         POLICY_RDLOCK;
1605
1606         fromcon = sidtab_search(&sidtab, fromsid);
1607         if (!fromcon) {
1608                 rc = -EINVAL;
1609                 goto out_unlock;
1610         }
1611
1612         user = hashtab_search(policydb.p_users.table, username);
1613         if (!user) {
1614                 rc = -EINVAL;
1615                 goto out_unlock;
1616         }
1617         usercon.user = user->value;
1618
1619         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1620         if (!mysids) {
1621                 rc = -ENOMEM;
1622                 goto out_unlock;
1623         }
1624
1625         ebitmap_for_each_bit(&user->roles, rnode, i) {
1626                 if (!ebitmap_node_get_bit(rnode, i))
1627                         continue;
1628                 role = policydb.role_val_to_struct[i];
1629                 usercon.role = i+1;
1630                 ebitmap_for_each_bit(&role->types, tnode, j) {
1631                         if (!ebitmap_node_get_bit(tnode, j))
1632                                 continue;
1633                         usercon.type = j+1;
1634
1635                         if (mls_setup_user_range(fromcon, user, &usercon))
1636                                 continue;
1637
1638                         rc = context_struct_compute_av(fromcon, &usercon,
1639                                                        SECCLASS_PROCESS,
1640                                                        PROCESS__TRANSITION,
1641                                                        &avd);
1642                         if (rc ||  !(avd.allowed & PROCESS__TRANSITION))
1643                                 continue;
1644                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1645                         if (rc) {
1646                                 kfree(mysids);
1647                                 goto out_unlock;
1648                         }
1649                         if (mynel < maxnel) {
1650                                 mysids[mynel++] = sid;
1651                         } else {
1652                                 maxnel += SIDS_NEL;
1653                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1654                                 if (!mysids2) {
1655                                         rc = -ENOMEM;
1656                                         kfree(mysids);
1657                                         goto out_unlock;
1658                                 }
1659                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1660                                 kfree(mysids);
1661                                 mysids = mysids2;
1662                                 mysids[mynel++] = sid;
1663                         }
1664                 }
1665         }
1666
1667         *sids = mysids;
1668         *nel = mynel;
1669
1670 out_unlock:
1671         POLICY_RDUNLOCK;
1672 out:
1673         return rc;
1674 }
1675
1676 /**
1677  * security_genfs_sid - Obtain a SID for a file in a filesystem
1678  * @fstype: filesystem type
1679  * @path: path from root of mount
1680  * @sclass: file security class
1681  * @sid: SID for path
1682  *
1683  * Obtain a SID to use for a file in a filesystem that
1684  * cannot support xattr or use a fixed labeling behavior like
1685  * transition SIDs or task SIDs.
1686  */
1687 int security_genfs_sid(const char *fstype,
1688                        char *path,
1689                        u16 sclass,
1690                        u32 *sid)
1691 {
1692         int len;
1693         struct genfs *genfs;
1694         struct ocontext *c;
1695         int rc = 0, cmp = 0;
1696
1697         POLICY_RDLOCK;
1698
1699         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
1700                 cmp = strcmp(fstype, genfs->fstype);
1701                 if (cmp <= 0)
1702                         break;
1703         }
1704
1705         if (!genfs || cmp) {
1706                 *sid = SECINITSID_UNLABELED;
1707                 rc = -ENOENT;
1708                 goto out;
1709         }
1710
1711         for (c = genfs->head; c; c = c->next) {
1712                 len = strlen(c->u.name);
1713                 if ((!c->v.sclass || sclass == c->v.sclass) &&
1714                     (strncmp(c->u.name, path, len) == 0))
1715                         break;
1716         }
1717
1718         if (!c) {
1719                 *sid = SECINITSID_UNLABELED;
1720                 rc = -ENOENT;
1721                 goto out;
1722         }
1723
1724         if (!c->sid[0]) {
1725                 rc = sidtab_context_to_sid(&sidtab,
1726                                            &c->context[0],
1727                                            &c->sid[0]);
1728                 if (rc)
1729                         goto out;
1730         }
1731
1732         *sid = c->sid[0];
1733 out:
1734         POLICY_RDUNLOCK;
1735         return rc;
1736 }
1737
1738 /**
1739  * security_fs_use - Determine how to handle labeling for a filesystem.
1740  * @fstype: filesystem type
1741  * @behavior: labeling behavior
1742  * @sid: SID for filesystem (superblock)
1743  */
1744 int security_fs_use(
1745         const char *fstype,
1746         unsigned int *behavior,
1747         u32 *sid)
1748 {
1749         int rc = 0;
1750         struct ocontext *c;
1751
1752         POLICY_RDLOCK;
1753
1754         c = policydb.ocontexts[OCON_FSUSE];
1755         while (c) {
1756                 if (strcmp(fstype, c->u.name) == 0)
1757                         break;
1758                 c = c->next;
1759         }
1760
1761         if (c) {
1762                 *behavior = c->v.behavior;
1763                 if (!c->sid[0]) {
1764                         rc = sidtab_context_to_sid(&sidtab,
1765                                                    &c->context[0],
1766                                                    &c->sid[0]);
1767                         if (rc)
1768                                 goto out;
1769                 }
1770                 *sid = c->sid[0];
1771         } else {
1772                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
1773                 if (rc) {
1774                         *behavior = SECURITY_FS_USE_NONE;
1775                         rc = 0;
1776                 } else {
1777                         *behavior = SECURITY_FS_USE_GENFS;
1778                 }
1779         }
1780
1781 out:
1782         POLICY_RDUNLOCK;
1783         return rc;
1784 }
1785
1786 int security_get_bools(int *len, char ***names, int **values)
1787 {
1788         int i, rc = -ENOMEM;
1789
1790         POLICY_RDLOCK;
1791         *names = NULL;
1792         *values = NULL;
1793
1794         *len = policydb.p_bools.nprim;
1795         if (!*len) {
1796                 rc = 0;
1797                 goto out;
1798         }
1799
1800        *names = kcalloc(*len, sizeof(char*), GFP_ATOMIC);
1801         if (!*names)
1802                 goto err;
1803
1804        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
1805         if (!*values)
1806                 goto err;
1807
1808         for (i = 0; i < *len; i++) {
1809                 size_t name_len;
1810                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
1811                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
1812                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
1813                 if (!(*names)[i])
1814                         goto err;
1815                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
1816                 (*names)[i][name_len - 1] = 0;
1817         }
1818         rc = 0;
1819 out:
1820         POLICY_RDUNLOCK;
1821         return rc;
1822 err:
1823         if (*names) {
1824                 for (i = 0; i < *len; i++)
1825                         kfree((*names)[i]);
1826         }
1827         kfree(*values);
1828         goto out;
1829 }
1830
1831
1832 int security_set_bools(int len, int *values)
1833 {
1834         int i, rc = 0;
1835         int lenp, seqno = 0;
1836         struct cond_node *cur;
1837
1838         POLICY_WRLOCK;
1839
1840         lenp = policydb.p_bools.nprim;
1841         if (len != lenp) {
1842                 rc = -EFAULT;
1843                 goto out;
1844         }
1845
1846         for (i = 0; i < len; i++) {
1847                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
1848                         audit_log(current->audit_context, GFP_ATOMIC,
1849                                 AUDIT_MAC_CONFIG_CHANGE,
1850                                 "bool=%s val=%d old_val=%d auid=%u",
1851                                 policydb.p_bool_val_to_name[i],
1852                                 !!values[i],
1853                                 policydb.bool_val_to_struct[i]->state,
1854                                 audit_get_loginuid(current->audit_context));
1855                 }
1856                 if (values[i]) {
1857                         policydb.bool_val_to_struct[i]->state = 1;
1858                 } else {
1859                         policydb.bool_val_to_struct[i]->state = 0;
1860                 }
1861         }
1862
1863         for (cur = policydb.cond_list; cur != NULL; cur = cur->next) {
1864                 rc = evaluate_cond_node(&policydb, cur);
1865                 if (rc)
1866                         goto out;
1867         }
1868
1869         seqno = ++latest_granting;
1870
1871 out:
1872         POLICY_WRUNLOCK;
1873         if (!rc) {
1874                 avc_ss_reset(seqno);
1875                 selnl_notify_policyload(seqno);
1876                 selinux_xfrm_notify_policyload();
1877         }
1878         return rc;
1879 }
1880
1881 int security_get_bool_value(int bool)
1882 {
1883         int rc = 0;
1884         int len;
1885
1886         POLICY_RDLOCK;
1887
1888         len = policydb.p_bools.nprim;
1889         if (bool >= len) {
1890                 rc = -EFAULT;
1891                 goto out;
1892         }
1893
1894         rc = policydb.bool_val_to_struct[bool]->state;
1895 out:
1896         POLICY_RDUNLOCK;
1897         return rc;
1898 }
1899
1900 static int security_preserve_bools(struct policydb *p)
1901 {
1902         int rc, nbools = 0, *bvalues = NULL, i;
1903         char **bnames = NULL;
1904         struct cond_bool_datum *booldatum;
1905         struct cond_node *cur;
1906
1907         rc = security_get_bools(&nbools, &bnames, &bvalues);
1908         if (rc)
1909                 goto out;
1910         for (i = 0; i < nbools; i++) {
1911                 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
1912                 if (booldatum)
1913                         booldatum->state = bvalues[i];
1914         }
1915         for (cur = p->cond_list; cur != NULL; cur = cur->next) {
1916                 rc = evaluate_cond_node(p, cur);
1917                 if (rc)
1918                         goto out;
1919         }
1920
1921 out:
1922         if (bnames) {
1923                 for (i = 0; i < nbools; i++)
1924                         kfree(bnames[i]);
1925         }
1926         kfree(bnames);
1927         kfree(bvalues);
1928         return rc;
1929 }
1930
1931 /*
1932  * security_sid_mls_copy() - computes a new sid based on the given
1933  * sid and the mls portion of mls_sid.
1934  */
1935 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
1936 {
1937         struct context *context1;
1938         struct context *context2;
1939         struct context newcon;
1940         char *s;
1941         u32 len;
1942         int rc = 0;
1943
1944         if (!ss_initialized || !selinux_mls_enabled) {
1945                 *new_sid = sid;
1946                 goto out;
1947         }
1948
1949         context_init(&newcon);
1950
1951         POLICY_RDLOCK;
1952         context1 = sidtab_search(&sidtab, sid);
1953         if (!context1) {
1954                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1955                        "%d\n", sid);
1956                 rc = -EINVAL;
1957                 goto out_unlock;
1958         }
1959
1960         context2 = sidtab_search(&sidtab, mls_sid);
1961         if (!context2) {
1962                 printk(KERN_ERR "security_sid_mls_copy:  unrecognized SID "
1963                        "%d\n", mls_sid);
1964                 rc = -EINVAL;
1965                 goto out_unlock;
1966         }
1967
1968         newcon.user = context1->user;
1969         newcon.role = context1->role;
1970         newcon.type = context1->type;
1971         rc = mls_context_cpy(&newcon, context2);
1972         if (rc)
1973                 goto out_unlock;
1974
1975         /* Check the validity of the new context. */
1976         if (!policydb_context_isvalid(&policydb, &newcon)) {
1977                 rc = convert_context_handle_invalid_context(&newcon);
1978                 if (rc)
1979                         goto bad;
1980         }
1981
1982         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
1983         goto out_unlock;
1984
1985 bad:
1986         if (!context_struct_to_string(&newcon, &s, &len)) {
1987                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1988                           "security_sid_mls_copy: invalid context %s", s);
1989                 kfree(s);
1990         }
1991
1992 out_unlock:
1993         POLICY_RDUNLOCK;
1994         context_destroy(&newcon);
1995 out:
1996         return rc;
1997 }
1998
1999 struct selinux_audit_rule {
2000         u32 au_seqno;
2001         struct context au_ctxt;
2002 };
2003
2004 void selinux_audit_rule_free(struct selinux_audit_rule *rule)
2005 {
2006         if (rule) {
2007                 context_destroy(&rule->au_ctxt);
2008                 kfree(rule);
2009         }
2010 }
2011
2012 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr,
2013                             struct selinux_audit_rule **rule)
2014 {
2015         struct selinux_audit_rule *tmprule;
2016         struct role_datum *roledatum;
2017         struct type_datum *typedatum;
2018         struct user_datum *userdatum;
2019         int rc = 0;
2020
2021         *rule = NULL;
2022
2023         if (!ss_initialized)
2024                 return -ENOTSUPP;
2025
2026         switch (field) {
2027         case AUDIT_SUBJ_USER:
2028         case AUDIT_SUBJ_ROLE:
2029         case AUDIT_SUBJ_TYPE:
2030         case AUDIT_OBJ_USER:
2031         case AUDIT_OBJ_ROLE:
2032         case AUDIT_OBJ_TYPE:
2033                 /* only 'equals' and 'not equals' fit user, role, and type */
2034                 if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL)
2035                         return -EINVAL;
2036                 break;
2037         case AUDIT_SUBJ_SEN:
2038         case AUDIT_SUBJ_CLR:
2039         case AUDIT_OBJ_LEV_LOW:
2040         case AUDIT_OBJ_LEV_HIGH:
2041                 /* we do not allow a range, indicated by the presense of '-' */
2042                 if (strchr(rulestr, '-'))
2043                         return -EINVAL;
2044                 break;
2045         default:
2046                 /* only the above fields are valid */
2047                 return -EINVAL;
2048         }
2049
2050         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2051         if (!tmprule)
2052                 return -ENOMEM;
2053
2054         context_init(&tmprule->au_ctxt);
2055
2056         POLICY_RDLOCK;
2057
2058         tmprule->au_seqno = latest_granting;
2059
2060         switch (field) {
2061         case AUDIT_SUBJ_USER:
2062         case AUDIT_OBJ_USER:
2063                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2064                 if (!userdatum)
2065                         rc = -EINVAL;
2066                 else
2067                         tmprule->au_ctxt.user = userdatum->value;
2068                 break;
2069         case AUDIT_SUBJ_ROLE:
2070         case AUDIT_OBJ_ROLE:
2071                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2072                 if (!roledatum)
2073                         rc = -EINVAL;
2074                 else
2075                         tmprule->au_ctxt.role = roledatum->value;
2076                 break;
2077         case AUDIT_SUBJ_TYPE:
2078         case AUDIT_OBJ_TYPE:
2079                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2080                 if (!typedatum)
2081                         rc = -EINVAL;
2082                 else
2083                         tmprule->au_ctxt.type = typedatum->value;
2084                 break;
2085         case AUDIT_SUBJ_SEN:
2086         case AUDIT_SUBJ_CLR:
2087         case AUDIT_OBJ_LEV_LOW:
2088         case AUDIT_OBJ_LEV_HIGH:
2089                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2090                 break;
2091         }
2092
2093         POLICY_RDUNLOCK;
2094
2095         if (rc) {
2096                 selinux_audit_rule_free(tmprule);
2097                 tmprule = NULL;
2098         }
2099
2100         *rule = tmprule;
2101
2102         return rc;
2103 }
2104
2105 int selinux_audit_rule_match(u32 sid, u32 field, u32 op,
2106                              struct selinux_audit_rule *rule,
2107                              struct audit_context *actx)
2108 {
2109         struct context *ctxt;
2110         struct mls_level *level;
2111         int match = 0;
2112
2113         if (!rule) {
2114                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2115                           "selinux_audit_rule_match: missing rule\n");
2116                 return -ENOENT;
2117         }
2118
2119         POLICY_RDLOCK;
2120
2121         if (rule->au_seqno < latest_granting) {
2122                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2123                           "selinux_audit_rule_match: stale rule\n");
2124                 match = -ESTALE;
2125                 goto out;
2126         }
2127
2128         ctxt = sidtab_search(&sidtab, sid);
2129         if (!ctxt) {
2130                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2131                           "selinux_audit_rule_match: unrecognized SID %d\n",
2132                           sid);
2133                 match = -ENOENT;
2134                 goto out;
2135         }
2136
2137         /* a field/op pair that is not caught here will simply fall through
2138            without a match */
2139         switch (field) {
2140         case AUDIT_SUBJ_USER:
2141         case AUDIT_OBJ_USER:
2142                 switch (op) {
2143                 case AUDIT_EQUAL:
2144                         match = (ctxt->user == rule->au_ctxt.user);
2145                         break;
2146                 case AUDIT_NOT_EQUAL:
2147                         match = (ctxt->user != rule->au_ctxt.user);
2148                         break;
2149                 }
2150                 break;
2151         case AUDIT_SUBJ_ROLE:
2152         case AUDIT_OBJ_ROLE:
2153                 switch (op) {
2154                 case AUDIT_EQUAL:
2155                         match = (ctxt->role == rule->au_ctxt.role);
2156                         break;
2157                 case AUDIT_NOT_EQUAL:
2158                         match = (ctxt->role != rule->au_ctxt.role);
2159                         break;
2160                 }
2161                 break;
2162         case AUDIT_SUBJ_TYPE:
2163         case AUDIT_OBJ_TYPE:
2164                 switch (op) {
2165                 case AUDIT_EQUAL:
2166                         match = (ctxt->type == rule->au_ctxt.type);
2167                         break;
2168                 case AUDIT_NOT_EQUAL:
2169                         match = (ctxt->type != rule->au_ctxt.type);
2170                         break;
2171                 }
2172                 break;
2173         case AUDIT_SUBJ_SEN:
2174         case AUDIT_SUBJ_CLR:
2175         case AUDIT_OBJ_LEV_LOW:
2176         case AUDIT_OBJ_LEV_HIGH:
2177                 level = ((field == AUDIT_SUBJ_SEN ||
2178                           field == AUDIT_OBJ_LEV_LOW) ?
2179                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2180                 switch (op) {
2181                 case AUDIT_EQUAL:
2182                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2183                                              level);
2184                         break;
2185                 case AUDIT_NOT_EQUAL:
2186                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2187                                               level);
2188                         break;
2189                 case AUDIT_LESS_THAN:
2190                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2191                                                level) &&
2192                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2193                                                level));
2194                         break;
2195                 case AUDIT_LESS_THAN_OR_EQUAL:
2196                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2197                                               level);
2198                         break;
2199                 case AUDIT_GREATER_THAN:
2200                         match = (mls_level_dom(level,
2201                                               &rule->au_ctxt.range.level[0]) &&
2202                                  !mls_level_eq(level,
2203                                                &rule->au_ctxt.range.level[0]));
2204                         break;
2205                 case AUDIT_GREATER_THAN_OR_EQUAL:
2206                         match = mls_level_dom(level,
2207                                               &rule->au_ctxt.range.level[0]);
2208                         break;
2209                 }
2210         }
2211
2212 out:
2213         POLICY_RDUNLOCK;
2214         return match;
2215 }
2216
2217 static int (*aurule_callback)(void) = NULL;
2218
2219 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2220                                u16 class, u32 perms, u32 *retained)
2221 {
2222         int err = 0;
2223
2224         if (event == AVC_CALLBACK_RESET && aurule_callback)
2225                 err = aurule_callback();
2226         return err;
2227 }
2228
2229 static int __init aurule_init(void)
2230 {
2231         int err;
2232
2233         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2234                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2235         if (err)
2236                 panic("avc_add_callback() failed, error %d\n", err);
2237
2238         return err;
2239 }
2240 __initcall(aurule_init);
2241
2242 void selinux_audit_set_callback(int (*callback)(void))
2243 {
2244         aurule_callback = callback;
2245 }
2246
2247 #ifdef CONFIG_NETLABEL
2248 /*
2249  * NetLabel cache structure
2250  */
2251 #define NETLBL_CACHE(x)           ((struct selinux_netlbl_cache *)(x))
2252 #define NETLBL_CACHE_T_NONE       0
2253 #define NETLBL_CACHE_T_SID        1
2254 #define NETLBL_CACHE_T_MLS        2
2255 struct selinux_netlbl_cache {
2256         u32 type;
2257         union {
2258                 u32 sid;
2259                 struct mls_range mls_label;
2260         } data;
2261 };
2262
2263 /**
2264  * security_netlbl_cache_free - Free the NetLabel cached data
2265  * @data: the data to free
2266  *
2267  * Description:
2268  * This function is intended to be used as the free() callback inside the
2269  * netlbl_lsm_cache structure.
2270  *
2271  */
2272 static void security_netlbl_cache_free(const void *data)
2273 {
2274         struct selinux_netlbl_cache *cache;
2275
2276         if (data == NULL)
2277                 return;
2278
2279         cache = NETLBL_CACHE(data);
2280         switch (cache->type) {
2281         case NETLBL_CACHE_T_MLS:
2282                 ebitmap_destroy(&cache->data.mls_label.level[0].cat);
2283                 break;
2284         }
2285         kfree(data);
2286 }
2287
2288 /**
2289  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2290  * @secattr: the NetLabel packet security attributes
2291  * @ctx: the SELinux context
2292  *
2293  * Description:
2294  * Attempt to cache the context in @ctx, which was derived from the packet in
2295  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2296  * already been initialized.
2297  *
2298  */
2299 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2300                                       struct context *ctx)
2301 {
2302         struct selinux_netlbl_cache *cache = NULL;
2303
2304         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2305         if (secattr->cache == NULL)
2306                 return;
2307
2308         cache = kzalloc(sizeof(*cache), GFP_ATOMIC);
2309         if (cache == NULL)
2310                 return;
2311
2312         cache->type = NETLBL_CACHE_T_MLS;
2313         if (ebitmap_cpy(&cache->data.mls_label.level[0].cat,
2314                         &ctx->range.level[0].cat) != 0)
2315                 return;
2316         cache->data.mls_label.level[1].cat.highbit =
2317                 cache->data.mls_label.level[0].cat.highbit;
2318         cache->data.mls_label.level[1].cat.node =
2319                 cache->data.mls_label.level[0].cat.node;
2320         cache->data.mls_label.level[0].sens = ctx->range.level[0].sens;
2321         cache->data.mls_label.level[1].sens = ctx->range.level[0].sens;
2322
2323         secattr->cache->free = security_netlbl_cache_free;
2324         secattr->cache->data = (void *)cache;
2325         secattr->flags |= NETLBL_SECATTR_CACHE;
2326 }
2327
2328 /**
2329  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2330  * @secattr: the NetLabel packet security attributes
2331  * @base_sid: the SELinux SID to use as a context for MLS only attributes
2332  * @sid: the SELinux SID
2333  *
2334  * Description:
2335  * Convert the given NetLabel security attributes in @secattr into a
2336  * SELinux SID.  If the @secattr field does not contain a full SELinux
2337  * SID/context then use the context in @base_sid as the foundation.  If
2338  * possibile the 'cache' field of @secattr is set and the CACHE flag is set;
2339  * this is to allow the @secattr to be used by NetLabel to cache the secattr to
2340  * SID conversion for future lookups.  Returns zero on success, negative
2341  * values on failure.
2342  *
2343  */
2344 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2345                                    u32 base_sid,
2346                                    u32 *sid)
2347 {
2348         int rc = -EIDRM;
2349         struct context *ctx;
2350         struct context ctx_new;
2351         struct selinux_netlbl_cache *cache;
2352
2353         if (!ss_initialized) {
2354                 *sid = SECSID_NULL;
2355                 return 0;
2356         }
2357
2358         POLICY_RDLOCK;
2359
2360         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2361                 cache = NETLBL_CACHE(secattr->cache->data);
2362                 switch (cache->type) {
2363                 case NETLBL_CACHE_T_SID:
2364                         *sid = cache->data.sid;
2365                         rc = 0;
2366                         break;
2367                 case NETLBL_CACHE_T_MLS:
2368                         ctx = sidtab_search(&sidtab, base_sid);
2369                         if (ctx == NULL)
2370                                 goto netlbl_secattr_to_sid_return;
2371
2372                         ctx_new.user = ctx->user;
2373                         ctx_new.role = ctx->role;
2374                         ctx_new.type = ctx->type;
2375                         ctx_new.range.level[0].sens =
2376                                 cache->data.mls_label.level[0].sens;
2377                         ctx_new.range.level[0].cat.highbit =
2378                                 cache->data.mls_label.level[0].cat.highbit;
2379                         ctx_new.range.level[0].cat.node =
2380                                 cache->data.mls_label.level[0].cat.node;
2381                         ctx_new.range.level[1].sens =
2382                                 cache->data.mls_label.level[1].sens;
2383                         ctx_new.range.level[1].cat.highbit =
2384                                 cache->data.mls_label.level[1].cat.highbit;
2385                         ctx_new.range.level[1].cat.node =
2386                                 cache->data.mls_label.level[1].cat.node;
2387
2388                         rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2389                         break;
2390                 default:
2391                         goto netlbl_secattr_to_sid_return;
2392                 }
2393         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2394                 ctx = sidtab_search(&sidtab, base_sid);
2395                 if (ctx == NULL)
2396                         goto netlbl_secattr_to_sid_return;
2397
2398                 ctx_new.user = ctx->user;
2399                 ctx_new.role = ctx->role;
2400                 ctx_new.type = ctx->type;
2401                 mls_import_netlbl_lvl(&ctx_new, secattr);
2402                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2403                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2404                                                   secattr->mls_cat) != 0)
2405                                 goto netlbl_secattr_to_sid_return;
2406                         ctx_new.range.level[1].cat.highbit =
2407                                 ctx_new.range.level[0].cat.highbit;
2408                         ctx_new.range.level[1].cat.node =
2409                                 ctx_new.range.level[0].cat.node;
2410                 } else {
2411                         ebitmap_init(&ctx_new.range.level[0].cat);
2412                         ebitmap_init(&ctx_new.range.level[1].cat);
2413                 }
2414                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2415                         goto netlbl_secattr_to_sid_return_cleanup;
2416
2417                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2418                 if (rc != 0)
2419                         goto netlbl_secattr_to_sid_return_cleanup;
2420
2421                 security_netlbl_cache_add(secattr, &ctx_new);
2422
2423                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2424         } else {
2425                 *sid = SECSID_NULL;
2426                 rc = 0;
2427         }
2428
2429 netlbl_secattr_to_sid_return:
2430         POLICY_RDUNLOCK;
2431         return rc;
2432 netlbl_secattr_to_sid_return_cleanup:
2433         ebitmap_destroy(&ctx_new.range.level[0].cat);
2434         goto netlbl_secattr_to_sid_return;
2435 }
2436
2437 /**
2438  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2439  * @sid: the SELinux SID
2440  * @secattr: the NetLabel packet security attributes
2441  *
2442  * Description:
2443  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2444  * Returns zero on success, negative values on failure.
2445  *
2446  */
2447 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2448 {
2449         int rc = -ENOENT;
2450         struct context *ctx;
2451
2452         netlbl_secattr_init(secattr);
2453
2454         if (!ss_initialized)
2455                 return 0;
2456
2457         POLICY_RDLOCK;
2458         ctx = sidtab_search(&sidtab, sid);
2459         if (ctx == NULL)
2460                 goto netlbl_sid_to_secattr_failure;
2461         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2462                                   GFP_ATOMIC);
2463         secattr->flags |= NETLBL_SECATTR_DOMAIN;
2464         mls_export_netlbl_lvl(ctx, secattr);
2465         rc = mls_export_netlbl_cat(ctx, secattr);
2466         if (rc != 0)
2467                 goto netlbl_sid_to_secattr_failure;
2468         POLICY_RDUNLOCK;
2469
2470         return 0;
2471
2472 netlbl_sid_to_secattr_failure:
2473         POLICY_RDUNLOCK;
2474         netlbl_secattr_destroy(secattr);
2475         return rc;
2476 }
2477 #endif /* CONFIG_NETLABEL */