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   1 /*
   2  * Implementation of the security services.
   3  *
   4  * Authors : Stephen Smalley, <sds@epoch.ncsc.mil>
   5  *           James Morris <jmorris@redhat.com>
   6  *
   7  * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com>
   8  *
   9  *      Support for enhanced MLS infrastructure.
  10  *      Support for context based audit filters.
  11  *
  12  * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com>
  13  *
  14  *      Added conditional policy language extensions
  15  *
  16  * Updated: Hewlett-Packard <paul.moore@hp.com>
  17  *
  18  *      Added support for NetLabel
  19  *      Added support for the policy capability bitmap
  20  *
  21  * Updated: Chad Sellers <csellers@tresys.com>
  22  *
  23  *  Added validation of kernel classes and permissions
  24  *
  25  * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P.
  26  * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc.
  27  * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC
  28  * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com>
  29  *      This program is free software; you can redistribute it and/or modify
  30  *      it under the terms of the GNU General Public License as published by
  31  *      the Free Software Foundation, version 2.
  32  */
  33 #include <linux/kernel.h>
  34 #include <linux/slab.h>
  35 #include <linux/string.h>
  36 #include <linux/spinlock.h>
  37 #include <linux/rcupdate.h>
  38 #include <linux/errno.h>
  39 #include <linux/in.h>
  40 #include <linux/sched.h>
  41 #include <linux/audit.h>
  42 #include <linux/mutex.h>
  43 #include <linux/selinux.h>
  44 #include <net/netlabel.h>
  45
  46 #include "flask.h"
  47 #include "avc.h"
  48 #include "avc_ss.h"
  49 #include "security.h"
  50 #include "context.h"
  51 #include "policydb.h"
  52 #include "sidtab.h"
  53 #include "services.h"
  54 #include "conditional.h"
  55 #include "mls.h"
  56 #include "objsec.h"
  57 #include "netlabel.h"
  58 #include "xfrm.h"
  59 #include "ebitmap.h"
  60 #include "audit.h"
  61
  62 extern void selnl_notify_policyload(u32 seqno);
  63 unsigned int policydb_loaded_version;
  64
  65 int selinux_policycap_netpeer;
  66 int selinux_policycap_openperm;
  67
  68 /*
  69  * This is declared in avc.c
  70  */
  71 extern const struct selinux_class_perm selinux_class_perm;
  72
  73 static DEFINE_RWLOCK(policy_rwlock);
  74
  75 static struct sidtab sidtab;
  76 struct policydb policydb;
  77 int ss_initialized;
  78
  79 /*
  80  * The largest sequence number that has been used when
  81  * providing an access decision to the access vector cache.
  82  * The sequence number only changes when a policy change
  83  * occurs.
  84  */
  85 static u32 latest_granting;
  86
  87 /* Forward declaration. */
  88 static int context_struct_to_string(struct context *context, char **scontext,
  89                                     u32 *scontext_len);
  90
  91 static int context_struct_compute_av(struct context *scontext,
  92                                      struct context *tcontext,
  93                                      u16 tclass,
  94                                      u32 requested,
  95                                      struct av_decision *avd);
  96 /*
  97  * Return the boolean value of a constraint expression
  98  * when it is applied to the specified source and target
  99  * security contexts.
 100  *
 101  * xcontext is a special beast...  It is used by the validatetrans rules
 102  * only.  For these rules, scontext is the context before the transition,
 103  * tcontext is the context after the transition, and xcontext is the context
 104  * of the process performing the transition.  All other callers of
 105  * constraint_expr_eval should pass in NULL for xcontext.
 106  */
 107 static int constraint_expr_eval(struct context *scontext,
 108                                 struct context *tcontext,
 109                                 struct context *xcontext,
 110                                 struct constraint_expr *cexpr)
 111 {
 112         u32 val1, val2;
 113         struct context *c;
 114         struct role_datum *r1, *r2;
 115         struct mls_level *l1, *l2;
 116         struct constraint_expr *e;
 117         int s[CEXPR_MAXDEPTH];
 118         int sp = -1;
 119
 120         for (e = cexpr; e; e = e->next) {
 121                 switch (e->expr_type) {
 122                 case CEXPR_NOT:
 123                         BUG_ON(sp < 0);
 124                         s[sp] = !s[sp];
 125                         break;
 126                 case CEXPR_AND:
 127                         BUG_ON(sp < 1);
 128                         sp--;
 129                         s[sp] &= s[sp+1];
 130                         break;
 131                 case CEXPR_OR:
 132                         BUG_ON(sp < 1);
 133                         sp--;
 134                         s[sp] |= s[sp+1];
 135                         break;
 136                 case CEXPR_ATTR:
 137                         if (sp == (CEXPR_MAXDEPTH-1))
 138                                 return 0;
 139                         switch (e->attr) {
 140                         case CEXPR_USER:
 141                                 val1 = scontext->user;
 142                                 val2 = tcontext->user;
 143                                 break;
 144                         case CEXPR_TYPE:
 145                                 val1 = scontext->type;
 146                                 val2 = tcontext->type;
 147                                 break;
 148                         case CEXPR_ROLE:
 149                                 val1 = scontext->role;
 150                                 val2 = tcontext->role;
 151                                 r1 = policydb.role_val_to_struct[val1 - 1];
 152                                 r2 = policydb.role_val_to_struct[val2 - 1];
 153                                 switch (e->op) {
 154                                 case CEXPR_DOM:
 155                                         s[++sp] = ebitmap_get_bit(&r1->dominates,
 156                                                                   val2 - 1);
 157                                         continue;
 158                                 case CEXPR_DOMBY:
 159                                         s[++sp] = ebitmap_get_bit(&r2->dominates,
 160                                                                   val1 - 1);
 161                                         continue;
 162                                 case CEXPR_INCOMP:
 163                                         s[++sp] = (!ebitmap_get_bit(&r1->dominates,
 164                                                                     val2 - 1) &&
 165                                                    !ebitmap_get_bit(&r2->dominates,
 166                                                                     val1 - 1));
 167                                         continue;
 168                                 default:
 169                                         break;
 170                                 }
 171                                 break;
 172                         case CEXPR_L1L2:
 173                                 l1 = &(scontext->range.level[0]);
 174                                 l2 = &(tcontext->range.level[0]);
 175                                 goto mls_ops;
 176                         case CEXPR_L1H2:
 177                                 l1 = &(scontext->range.level[0]);
 178                                 l2 = &(tcontext->range.level[1]);
 179                                 goto mls_ops;
 180                         case CEXPR_H1L2:
 181                                 l1 = &(scontext->range.level[1]);
 182                                 l2 = &(tcontext->range.level[0]);
 183                                 goto mls_ops;
 184                         case CEXPR_H1H2:
 185                                 l1 = &(scontext->range.level[1]);
 186                                 l2 = &(tcontext->range.level[1]);
 187                                 goto mls_ops;
 188                         case CEXPR_L1H1:
 189                                 l1 = &(scontext->range.level[0]);
 190                                 l2 = &(scontext->range.level[1]);
 191                                 goto mls_ops;
 192                         case CEXPR_L2H2:
 193                                 l1 = &(tcontext->range.level[0]);
 194                                 l2 = &(tcontext->range.level[1]);
 195                                 goto mls_ops;
 196 mls_ops:
 197                         switch (e->op) {
 198                         case CEXPR_EQ:
 199                                 s[++sp] = mls_level_eq(l1, l2);
 200                                 continue;
 201                         case CEXPR_NEQ:
 202                                 s[++sp] = !mls_level_eq(l1, l2);
 203                                 continue;
 204                         case CEXPR_DOM:
 205                                 s[++sp] = mls_level_dom(l1, l2);
 206                                 continue;
 207                         case CEXPR_DOMBY:
 208                                 s[++sp] = mls_level_dom(l2, l1);
 209                                 continue;
 210                         case CEXPR_INCOMP:
 211                                 s[++sp] = mls_level_incomp(l2, l1);
 212                                 continue;
 213                         default:
 214                                 BUG();
 215                                 return 0;
 216                         }
 217                         break;
 218                         default:
 219                                 BUG();
 220                                 return 0;
 221                         }
 222
 223                         switch (e->op) {
 224                         case CEXPR_EQ:
 225                                 s[++sp] = (val1 == val2);
 226                                 break;
 227                         case CEXPR_NEQ:
 228                                 s[++sp] = (val1 != val2);
 229                                 break;
 230                         default:
 231                                 BUG();
 232                                 return 0;
 233                         }
 234                         break;
 235                 case CEXPR_NAMES:
 236                         if (sp == (CEXPR_MAXDEPTH-1))
 237                                 return 0;
 238                         c = scontext;
 239                         if (e->attr & CEXPR_TARGET)
 240                                 c = tcontext;
 241                         else if (e->attr & CEXPR_XTARGET) {
 242                                 c = xcontext;
 243                                 if (!c) {
 244                                         BUG();
 245                                         return 0;
 246                                 }
 247                         }
 248                         if (e->attr & CEXPR_USER)
 249                                 val1 = c->user;
 250                         else if (e->attr & CEXPR_ROLE)
 251                                 val1 = c->role;
 252                         else if (e->attr & CEXPR_TYPE)
 253                                 val1 = c->type;
 254                         else {
 255                                 BUG();
 256                                 return 0;
 257                         }
 258
 259                         switch (e->op) {
 260                         case CEXPR_EQ:
 261                                 s[++sp] = ebitmap_get_bit(&e->names, val1 - 1);
 262                                 break;
 263                         case CEXPR_NEQ:
 264                                 s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1);
 265                                 break;
 266                         default:
 267                                 BUG();
 268                                 return 0;
 269                         }
 270                         break;
 271                 default:
 272                         BUG();
 273                         return 0;
 274                 }
 275         }
 276
 277         BUG_ON(sp != 0);
 278         return s[0];
 279 }
 280
 281 /*
 282  * security_boundary_permission - drops violated permissions
 283  * on boundary constraint.
 284  */
 285 static void type_attribute_bounds_av(struct context *scontext,
 286                                      struct context *tcontext,
 287                                      u16 tclass,
 288                                      u32 requested,
 289                                      struct av_decision *avd)
 290 {
 291         struct context lo_scontext;
 292         struct context lo_tcontext;
 293         struct av_decision lo_avd;
 294         struct type_datum *source
 295                 = policydb.type_val_to_struct[scontext->type - 1];
 296         struct type_datum *target
 297                 = policydb.type_val_to_struct[tcontext->type - 1];
 298         u32 masked = 0;
 299
 300         if (source->bounds) {
 301                 memset(&lo_avd, 0, sizeof(lo_avd));
 302
 303                 memcpy(&lo_scontext, scontext, sizeof(lo_scontext));
 304                 lo_scontext.type = source->bounds;
 305
 306                 context_struct_compute_av(&lo_scontext,
 307                                           tcontext,
 308                                           tclass,
 309                                           requested,
 310                                           &lo_avd);
 311                 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
 312                         return;         /* no masked permission */
 313                 masked = ~lo_avd.allowed & avd->allowed;
 314         }
 315
 316         if (target->bounds) {
 317                 memset(&lo_avd, 0, sizeof(lo_avd));
 318
 319                 memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext));
 320                 lo_tcontext.type = target->bounds;
 321
 322                 context_struct_compute_av(scontext,
 323                                           &lo_tcontext,
 324                                           tclass,
 325                                           requested,
 326                                           &lo_avd);
 327                 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
 328                         return;         /* no masked permission */
 329                 masked = ~lo_avd.allowed & avd->allowed;
 330         }
 331
 332         if (source->bounds && target->bounds) {
 333                 memset(&lo_avd, 0, sizeof(lo_avd));
 334                 /*
 335                  * lo_scontext and lo_tcontext are already
 336                  * set up.
 337                  */
 338
 339                 context_struct_compute_av(&lo_scontext,
 340                                           &lo_tcontext,
 341                                           tclass,
 342                                           requested,
 343                                           &lo_avd);
 344                 if ((lo_avd.allowed & avd->allowed) == avd->allowed)
 345                         return;         /* no masked permission */
 346                 masked = ~lo_avd.allowed & avd->allowed;
 347         }
 348
 349         if (masked) {
 350                 struct audit_buffer *ab;
 351                 char *stype_name
 352                         = policydb.p_type_val_to_name[source->value - 1];
 353                 char *ttype_name
 354                         = policydb.p_type_val_to_name[target->value - 1];
 355                 char *tclass_name
 356                         = policydb.p_class_val_to_name[tclass - 1];
 357
 358                 /* mask violated permissions */
 359                 avd->allowed &= ~masked;
 360
 361                 /* notice to userspace via audit message */
 362                 ab = audit_log_start(current->audit_context,
 363                                      GFP_ATOMIC, AUDIT_SELINUX_ERR);
 364                 if (!ab)
 365                         return;
 366
 367                 audit_log_format(ab, "av boundary violation: "
 368                                  "source=%s target=%s tclass=%s",
 369                                  stype_name, ttype_name, tclass_name);
 370                 avc_dump_av(ab, tclass, masked);
 371                 audit_log_end(ab);
 372         }
 373 }
 374
 375 /*
 376  * Compute access vectors based on a context structure pair for
 377  * the permissions in a particular class.
 378  */
 379 static int context_struct_compute_av(struct context *scontext,
 380                                      struct context *tcontext,
 381                                      u16 tclass,
 382                                      u32 requested,
 383                                      struct av_decision *avd)
 384 {
 385         struct constraint_node *constraint;
 386         struct role_allow *ra;
 387         struct avtab_key avkey;
 388         struct avtab_node *node;
 389         struct class_datum *tclass_datum;
 390         struct ebitmap *sattr, *tattr;
 391         struct ebitmap_node *snode, *tnode;
 392         const struct selinux_class_perm *kdefs = &selinux_class_perm;
 393         unsigned int i, j;
 394
 395         /*
 396          * Remap extended Netlink classes for old policy versions.
 397          * Do this here rather than socket_type_to_security_class()
 398          * in case a newer policy version is loaded, allowing sockets
 399          * to remain in the correct class.
 400          */
 401         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 402                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 403                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 404                         tclass = SECCLASS_NETLINK_SOCKET;
 405
 406         /*
 407          * Initialize the access vectors to the default values.
 408          */
 409         avd->allowed = 0;
 410         avd->auditallow = 0;
 411         avd->auditdeny = 0xffffffff;
 412         avd->seqno = latest_granting;
 413
 414         /*
 415          * Check for all the invalid cases.
 416          * - tclass 0
 417          * - tclass > policy and > kernel
 418          * - tclass > policy but is a userspace class
 419          * - tclass > policy but we do not allow unknowns
 420          */
 421         if (unlikely(!tclass))
 422                 goto inval_class;
 423         if (unlikely(tclass > policydb.p_classes.nprim))
 424                 if (tclass > kdefs->cts_len ||
 425                     !kdefs->class_to_string[tclass] ||
 426                     !policydb.allow_unknown)
 427                         goto inval_class;
 428
 429         /*
 430          * Kernel class and we allow unknown so pad the allow decision
 431          * the pad will be all 1 for unknown classes.
 432          */
 433         if (tclass <= kdefs->cts_len && policydb.allow_unknown)
 434                 avd->allowed = policydb.undefined_perms[tclass - 1];
 435
 436         /*
 437          * Not in policy. Since decision is completed (all 1 or all 0) return.
 438          */
 439         if (unlikely(tclass > policydb.p_classes.nprim))
 440                 return 0;
 441
 442         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 443
 444         /*
 445          * If a specific type enforcement rule was defined for
 446          * this permission check, then use it.
 447          */
 448         avkey.target_class = tclass;
 449         avkey.specified = AVTAB_AV;
 450         sattr = &policydb.type_attr_map[scontext->type - 1];
 451         tattr = &policydb.type_attr_map[tcontext->type - 1];
 452         ebitmap_for_each_positive_bit(sattr, snode, i) {
 453                 ebitmap_for_each_positive_bit(tattr, tnode, j) {
 454                         avkey.source_type = i + 1;
 455                         avkey.target_type = j + 1;
 456                         for (node = avtab_search_node(&policydb.te_avtab, &avkey);
 457                              node;
 458                              node = avtab_search_node_next(node, avkey.specified)) {
 459                                 if (node->key.specified == AVTAB_ALLOWED)
 460                                         avd->allowed |= node->datum.data;
 461                                 else if (node->key.specified == AVTAB_AUDITALLOW)
 462                                         avd->auditallow |= node->datum.data;
 463                                 else if (node->key.specified == AVTAB_AUDITDENY)
 464                                         avd->auditdeny &= node->datum.data;
 465                         }
 466
 467                         /* Check conditional av table for additional permissions */
 468                         cond_compute_av(&policydb.te_cond_avtab, &avkey, avd);
 469
 470                 }
 471         }
 472
 473         /*
 474          * Remove any permissions prohibited by a constraint (this includes
 475          * the MLS policy).
 476          */
 477         constraint = tclass_datum->constraints;
 478         while (constraint) {
 479                 if ((constraint->permissions & (avd->allowed)) &&
 480                     !constraint_expr_eval(scontext, tcontext, NULL,
 481                                           constraint->expr)) {
 482                         avd->allowed &= ~(constraint->permissions);
 483                 }
 484                 constraint = constraint->next;
 485         }
 486
 487         /*
 488          * If checking process transition permission and the
 489          * role is changing, then check the (current_role, new_role)
 490          * pair.
 491          */
 492         if (tclass == SECCLASS_PROCESS &&
 493             (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) &&
 494             scontext->role != tcontext->role) {
 495                 for (ra = policydb.role_allow; ra; ra = ra->next) {
 496                         if (scontext->role == ra->role &&
 497                             tcontext->role == ra->new_role)
 498                                 break;
 499                 }
 500                 if (!ra)
 501                         avd->allowed &= ~(PROCESS__TRANSITION |
 502                                           PROCESS__DYNTRANSITION);
 503         }
 504
 505         /*
 506          * If the given source and target types have boundary
 507          * constraint, lazy checks have to mask any violated
 508          * permission and notice it to userspace via audit.
 509          */
 510         type_attribute_bounds_av(scontext, tcontext,
 511                                  tclass, requested, avd);
 512
 513         return 0;
 514
 515 inval_class:
 516         if (!tclass || tclass > kdefs->cts_len ||
 517             !kdefs->class_to_string[tclass]) {
 518                 if (printk_ratelimit())
 519                         printk(KERN_ERR "SELinux: %s:  unrecognized class %d\n",
 520                                __func__, tclass);
 521                 return -EINVAL;
 522         }
 523
 524         /*
 525          * Known to the kernel, but not to the policy.
 526          * Handle as a denial (allowed is 0).
 527          */
 528         return 0;
 529 }
 530
 531 /*
 532  * Given a sid find if the type has the permissive flag set
 533  */
 534 int security_permissive_sid(u32 sid)
 535 {
 536         struct context *context;
 537         u32 type;
 538         int rc;
 539
 540         read_lock(&policy_rwlock);
 541
 542         context = sidtab_search(&sidtab, sid);
 543         BUG_ON(!context);
 544
 545         type = context->type;
 546         /*
 547          * we are intentionally using type here, not type-1, the 0th bit may
 548          * someday indicate that we are globally setting permissive in policy.
 549          */
 550         rc = ebitmap_get_bit(&policydb.permissive_map, type);
 551
 552         read_unlock(&policy_rwlock);
 553         return rc;
 554 }
 555
 556 static int security_validtrans_handle_fail(struct context *ocontext,
 557                                            struct context *ncontext,
 558                                            struct context *tcontext,
 559                                            u16 tclass)
 560 {
 561         char *o = NULL, *n = NULL, *t = NULL;
 562         u32 olen, nlen, tlen;
 563
 564         if (context_struct_to_string(ocontext, &o, &olen) < 0)
 565                 goto out;
 566         if (context_struct_to_string(ncontext, &n, &nlen) < 0)
 567                 goto out;
 568         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
 569                 goto out;
 570         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
 571                   "security_validate_transition:  denied for"
 572                   " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s",
 573                   o, n, t, policydb.p_class_val_to_name[tclass-1]);
 574 out:
 575         kfree(o);
 576         kfree(n);
 577         kfree(t);
 578
 579         if (!selinux_enforcing)
 580                 return 0;
 581         return -EPERM;
 582 }
 583
 584 int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid,
 585                                  u16 tclass)
 586 {
 587         struct context *ocontext;
 588         struct context *ncontext;
 589         struct context *tcontext;
 590         struct class_datum *tclass_datum;
 591         struct constraint_node *constraint;
 592         int rc = 0;
 593
 594         if (!ss_initialized)
 595                 return 0;
 596
 597         read_lock(&policy_rwlock);
 598
 599         /*
 600          * Remap extended Netlink classes for old policy versions.
 601          * Do this here rather than socket_type_to_security_class()
 602          * in case a newer policy version is loaded, allowing sockets
 603          * to remain in the correct class.
 604          */
 605         if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS)
 606                 if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET &&
 607                     tclass <= SECCLASS_NETLINK_DNRT_SOCKET)
 608                         tclass = SECCLASS_NETLINK_SOCKET;
 609
 610         if (!tclass || tclass > policydb.p_classes.nprim) {
 611                 printk(KERN_ERR "SELinux: %s:  unrecognized class %d\n",
 612                         __func__, tclass);
 613                 rc = -EINVAL;
 614                 goto out;
 615         }
 616         tclass_datum = policydb.class_val_to_struct[tclass - 1];
 617
 618         ocontext = sidtab_search(&sidtab, oldsid);
 619         if (!ocontext) {
 620                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 621                         __func__, oldsid);
 622                 rc = -EINVAL;
 623                 goto out;
 624         }
 625
 626         ncontext = sidtab_search(&sidtab, newsid);
 627         if (!ncontext) {
 628                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 629                         __func__, newsid);
 630                 rc = -EINVAL;
 631                 goto out;
 632         }
 633
 634         tcontext = sidtab_search(&sidtab, tasksid);
 635         if (!tcontext) {
 636                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 637                         __func__, tasksid);
 638                 rc = -EINVAL;
 639                 goto out;
 640         }
 641
 642         constraint = tclass_datum->validatetrans;
 643         while (constraint) {
 644                 if (!constraint_expr_eval(ocontext, ncontext, tcontext,
 645                                           constraint->expr)) {
 646                         rc = security_validtrans_handle_fail(ocontext, ncontext,
 647                                                              tcontext, tclass);
 648                         goto out;
 649                 }
 650                 constraint = constraint->next;
 651         }
 652
 653 out:
 654         read_unlock(&policy_rwlock);
 655         return rc;
 656 }
 657
 658 /*
 659  * security_bounded_transition - check whether the given
 660  * transition is directed to bounded, or not.
 661  * It returns 0, if @newsid is bounded by @oldsid.
 662  * Otherwise, it returns error code.
 663  *
 664  * @oldsid : current security identifier
 665  * @newsid : destinated security identifier
 666  */
 667 int security_bounded_transition(u32 old_sid, u32 new_sid)
 668 {
 669         struct context *old_context, *new_context;
 670         struct type_datum *type;
 671         int index;
 672         int rc = -EINVAL;
 673
 674         read_lock(&policy_rwlock);
 675
 676         old_context = sidtab_search(&sidtab, old_sid);
 677         if (!old_context) {
 678                 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
 679                        __func__, old_sid);
 680                 goto out;
 681         }
 682
 683         new_context = sidtab_search(&sidtab, new_sid);
 684         if (!new_context) {
 685                 printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n",
 686                        __func__, new_sid);
 687                 goto out;
 688         }
 689
 690         /* type/domain unchaned */
 691         if (old_context->type == new_context->type) {
 692                 rc = 0;
 693                 goto out;
 694         }
 695
 696         index = new_context->type;
 697         while (true) {
 698                 type = policydb.type_val_to_struct[index - 1];
 699                 BUG_ON(!type);
 700
 701                 /* not bounded anymore */
 702                 if (!type->bounds) {
 703                         rc = -EPERM;
 704                         break;
 705                 }
 706
 707                 /* @newsid is bounded by @oldsid */
 708                 if (type->bounds == old_context->type) {
 709                         rc = 0;
 710                         break;
 711                 }
 712                 index = type->bounds;
 713         }
 714 out:
 715         read_unlock(&policy_rwlock);
 716
 717         return rc;
 718 }
 719
 720
 721 /**
 722  * security_compute_av - Compute access vector decisions.
 723  * @ssid: source security identifier
 724  * @tsid: target security identifier
 725  * @tclass: target security class
 726  * @requested: requested permissions
 727  * @avd: access vector decisions
 728  *
 729  * Compute a set of access vector decisions based on the
 730  * SID pair (@ssid, @tsid) for the permissions in @tclass.
 731  * Return -%EINVAL if any of the parameters are invalid or %0
 732  * if the access vector decisions were computed successfully.
 733  */
 734 int security_compute_av(u32 ssid,
 735                         u32 tsid,
 736                         u16 tclass,
 737                         u32 requested,
 738                         struct av_decision *avd)
 739 {
 740         struct context *scontext = NULL, *tcontext = NULL;
 741         int rc = 0;
 742
 743         if (!ss_initialized) {
 744                 avd->allowed = 0xffffffff;
 745                 avd->auditallow = 0;
 746                 avd->auditdeny = 0xffffffff;
 747                 avd->seqno = latest_granting;
 748                 return 0;
 749         }
 750
 751         read_lock(&policy_rwlock);
 752
 753         scontext = sidtab_search(&sidtab, ssid);
 754         if (!scontext) {
 755                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 756                        __func__, ssid);
 757                 rc = -EINVAL;
 758                 goto out;
 759         }
 760         tcontext = sidtab_search(&sidtab, tsid);
 761         if (!tcontext) {
 762                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 763                        __func__, tsid);
 764                 rc = -EINVAL;
 765                 goto out;
 766         }
 767
 768         rc = context_struct_compute_av(scontext, tcontext, tclass,
 769                                        requested, avd);
 770 out:
 771         read_unlock(&policy_rwlock);
 772         return rc;
 773 }
 774
 775 /*
 776  * Write the security context string representation of
 777  * the context structure `context' into a dynamically
 778  * allocated string of the correct size.  Set `*scontext'
 779  * to point to this string and set `*scontext_len' to
 780  * the length of the string.
 781  */
 782 static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len)
 783 {
 784         char *scontextp;
 785
 786         *scontext = NULL;
 787         *scontext_len = 0;
 788
 789         if (context->len) {
 790                 *scontext_len = context->len;
 791                 *scontext = kstrdup(context->str, GFP_ATOMIC);
 792                 if (!(*scontext))
 793                         return -ENOMEM;
 794                 return 0;
 795         }
 796
 797         /* Compute the size of the context. */
 798         *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1;
 799         *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1;
 800         *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1;
 801         *scontext_len += mls_compute_context_len(context);
 802
 803         /* Allocate space for the context; caller must free this space. */
 804         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 805         if (!scontextp)
 806                 return -ENOMEM;
 807         *scontext = scontextp;
 808
 809         /*
 810          * Copy the user name, role name and type name into the context.
 811          */
 812         sprintf(scontextp, "%s:%s:%s",
 813                 policydb.p_user_val_to_name[context->user - 1],
 814                 policydb.p_role_val_to_name[context->role - 1],
 815                 policydb.p_type_val_to_name[context->type - 1]);
 816         scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) +
 817                      1 + strlen(policydb.p_role_val_to_name[context->role - 1]) +
 818                      1 + strlen(policydb.p_type_val_to_name[context->type - 1]);
 819
 820         mls_sid_to_context(context, &scontextp);
 821
 822         *scontextp = 0;
 823
 824         return 0;
 825 }
 826
 827 #include "initial_sid_to_string.h"
 828
 829 const char *security_get_initial_sid_context(u32 sid)
 830 {
 831         if (unlikely(sid > SECINITSID_NUM))
 832                 return NULL;
 833         return initial_sid_to_string[sid];
 834 }
 835
 836 static int security_sid_to_context_core(u32 sid, char **scontext,
 837                                         u32 *scontext_len, int force)
 838 {
 839         struct context *context;
 840         int rc = 0;
 841
 842         *scontext = NULL;
 843         *scontext_len  = 0;
 844
 845         if (!ss_initialized) {
 846                 if (sid <= SECINITSID_NUM) {
 847                         char *scontextp;
 848
 849                         *scontext_len = strlen(initial_sid_to_string[sid]) + 1;
 850                         scontextp = kmalloc(*scontext_len, GFP_ATOMIC);
 851                         if (!scontextp) {
 852                                 rc = -ENOMEM;
 853                                 goto out;
 854                         }
 855                         strcpy(scontextp, initial_sid_to_string[sid]);
 856                         *scontext = scontextp;
 857                         goto out;
 858                 }
 859                 printk(KERN_ERR "SELinux: %s:  called before initial "
 860                        "load_policy on unknown SID %d\n", __func__, sid);
 861                 rc = -EINVAL;
 862                 goto out;
 863         }
 864         read_lock(&policy_rwlock);
 865         if (force)
 866                 context = sidtab_search_force(&sidtab, sid);
 867         else
 868                 context = sidtab_search(&sidtab, sid);
 869         if (!context) {
 870                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
 871                         __func__, sid);
 872                 rc = -EINVAL;
 873                 goto out_unlock;
 874         }
 875         rc = context_struct_to_string(context, scontext, scontext_len);
 876 out_unlock:
 877         read_unlock(&policy_rwlock);
 878 out:
 879         return rc;
 880
 881 }
 882
 883 /**
 884  * security_sid_to_context - Obtain a context for a given SID.
 885  * @sid: security identifier, SID
 886  * @scontext: security context
 887  * @scontext_len: length in bytes
 888  *
 889  * Write the string representation of the context associated with @sid
 890  * into a dynamically allocated string of the correct size.  Set @scontext
 891  * to point to this string and set @scontext_len to the length of the string.
 892  */
 893 int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len)
 894 {
 895         return security_sid_to_context_core(sid, scontext, scontext_len, 0);
 896 }
 897
 898 int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len)
 899 {
 900         return security_sid_to_context_core(sid, scontext, scontext_len, 1);
 901 }
 902
 903 /*
 904  * Caveat:  Mutates scontext.
 905  */
 906 static int string_to_context_struct(struct policydb *pol,
 907                                     struct sidtab *sidtabp,
 908                                     char *scontext,
 909                                     u32 scontext_len,
 910                                     struct context *ctx,
 911                                     u32 def_sid)
 912 {
 913         struct role_datum *role;
 914         struct type_datum *typdatum;
 915         struct user_datum *usrdatum;
 916         char *scontextp, *p, oldc;
 917         int rc = 0;
 918
 919         context_init(ctx);
 920
 921         /* Parse the security context. */
 922
 923         rc = -EINVAL;
 924         scontextp = (char *) scontext;
 925
 926         /* Extract the user. */
 927         p = scontextp;
 928         while (*p && *p != ':')
 929                 p++;
 930
 931         if (*p == 0)
 932                 goto out;
 933
 934         *p++ = 0;
 935
 936         usrdatum = hashtab_search(pol->p_users.table, scontextp);
 937         if (!usrdatum)
 938                 goto out;
 939
 940         ctx->user = usrdatum->value;
 941
 942         /* Extract role. */
 943         scontextp = p;
 944         while (*p && *p != ':')
 945                 p++;
 946
 947         if (*p == 0)
 948                 goto out;
 949
 950         *p++ = 0;
 951
 952         role = hashtab_search(pol->p_roles.table, scontextp);
 953         if (!role)
 954                 goto out;
 955         ctx->role = role->value;
 956
 957         /* Extract type. */
 958         scontextp = p;
 959         while (*p && *p != ':')
 960                 p++;
 961         oldc = *p;
 962         *p++ = 0;
 963
 964         typdatum = hashtab_search(pol->p_types.table, scontextp);
 965         if (!typdatum || typdatum->attribute)
 966                 goto out;
 967
 968         ctx->type = typdatum->value;
 969
 970         rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid);
 971         if (rc)
 972                 goto out;
 973
 974         if ((p - scontext) < scontext_len) {
 975                 rc = -EINVAL;
 976                 goto out;
 977         }
 978
 979         /* Check the validity of the new context. */
 980         if (!policydb_context_isvalid(pol, ctx)) {
 981                 rc = -EINVAL;
 982                 goto out;
 983         }
 984         rc = 0;
 985 out:
 986         if (rc)
 987                 context_destroy(ctx);
 988         return rc;
 989 }
 990
 991 static int security_context_to_sid_core(const char *scontext, u32 scontext_len,
 992                                         u32 *sid, u32 def_sid, gfp_t gfp_flags,
 993                                         int force)
 994 {
 995         char *scontext2, *str = NULL;
 996         struct context context;
 997         int rc = 0;
 998
 999         if (!ss_initialized) {
1000                 int i;
1001
1002                 for (i = 1; i < SECINITSID_NUM; i++) {
1003                         if (!strcmp(initial_sid_to_string[i], scontext)) {
1004                                 *sid = i;
1005                                 return 0;
1006                         }
1007                 }
1008                 *sid = SECINITSID_KERNEL;
1009                 return 0;
1010         }
1011         *sid = SECSID_NULL;
1012
1013         /* Copy the string so that we can modify the copy as we parse it. */
1014         scontext2 = kmalloc(scontext_len+1, gfp_flags);
1015         if (!scontext2)
1016                 return -ENOMEM;
1017         memcpy(scontext2, scontext, scontext_len);
1018         scontext2[scontext_len] = 0;
1019
1020         if (force) {
1021                 /* Save another copy for storing in uninterpreted form */
1022                 str = kstrdup(scontext2, gfp_flags);
1023                 if (!str) {
1024                         kfree(scontext2);
1025                         return -ENOMEM;
1026                 }
1027         }
1028
1029         read_lock(&policy_rwlock);
1030         rc = string_to_context_struct(&policydb, &sidtab,
1031                                       scontext2, scontext_len,
1032                                       &context, def_sid);
1033         if (rc == -EINVAL && force) {
1034                 context.str = str;
1035                 context.len = scontext_len;
1036                 str = NULL;
1037         } else if (rc)
1038                 goto out;
1039         rc = sidtab_context_to_sid(&sidtab, &context, sid);
1040         context_destroy(&context);
1041 out:
1042         read_unlock(&policy_rwlock);
1043         kfree(scontext2);
1044         kfree(str);
1045         return rc;
1046 }
1047
1048 /**
1049  * security_context_to_sid - Obtain a SID for a given security context.
1050  * @scontext: security context
1051  * @scontext_len: length in bytes
1052  * @sid: security identifier, SID
1053  *
1054  * Obtains a SID associated with the security context that
1055  * has the string representation specified by @scontext.
1056  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1057  * memory is available, or 0 on success.
1058  */
1059 int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid)
1060 {
1061         return security_context_to_sid_core(scontext, scontext_len,
1062                                             sid, SECSID_NULL, GFP_KERNEL, 0);
1063 }
1064
1065 /**
1066  * security_context_to_sid_default - Obtain a SID for a given security context,
1067  * falling back to specified default if needed.
1068  *
1069  * @scontext: security context
1070  * @scontext_len: length in bytes
1071  * @sid: security identifier, SID
1072  * @def_sid: default SID to assign on error
1073  *
1074  * Obtains a SID associated with the security context that
1075  * has the string representation specified by @scontext.
1076  * The default SID is passed to the MLS layer to be used to allow
1077  * kernel labeling of the MLS field if the MLS field is not present
1078  * (for upgrading to MLS without full relabel).
1079  * Implicitly forces adding of the context even if it cannot be mapped yet.
1080  * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
1081  * memory is available, or 0 on success.
1082  */
1083 int security_context_to_sid_default(const char *scontext, u32 scontext_len,
1084                                     u32 *sid, u32 def_sid, gfp_t gfp_flags)
1085 {
1086         return security_context_to_sid_core(scontext, scontext_len,
1087                                             sid, def_sid, gfp_flags, 1);
1088 }
1089
1090 int security_context_to_sid_force(const char *scontext, u32 scontext_len,
1091                                   u32 *sid)
1092 {
1093         return security_context_to_sid_core(scontext, scontext_len,
1094                                             sid, SECSID_NULL, GFP_KERNEL, 1);
1095 }
1096
1097 static int compute_sid_handle_invalid_context(
1098         struct context *scontext,
1099         struct context *tcontext,
1100         u16 tclass,
1101         struct context *newcontext)
1102 {
1103         char *s = NULL, *t = NULL, *n = NULL;
1104         u32 slen, tlen, nlen;
1105
1106         if (context_struct_to_string(scontext, &s, &slen) < 0)
1107                 goto out;
1108         if (context_struct_to_string(tcontext, &t, &tlen) < 0)
1109                 goto out;
1110         if (context_struct_to_string(newcontext, &n, &nlen) < 0)
1111                 goto out;
1112         audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
1113                   "security_compute_sid:  invalid context %s"
1114                   " for scontext=%s"
1115                   " tcontext=%s"
1116                   " tclass=%s",
1117                   n, s, t, policydb.p_class_val_to_name[tclass-1]);
1118 out:
1119         kfree(s);
1120         kfree(t);
1121         kfree(n);
1122         if (!selinux_enforcing)
1123                 return 0;
1124         return -EACCES;
1125 }
1126
1127 static int security_compute_sid(u32 ssid,
1128                                 u32 tsid,
1129                                 u16 tclass,
1130                                 u32 specified,
1131                                 u32 *out_sid)
1132 {
1133         struct context *scontext = NULL, *tcontext = NULL, newcontext;
1134         struct role_trans *roletr = NULL;
1135         struct avtab_key avkey;
1136         struct avtab_datum *avdatum;
1137         struct avtab_node *node;
1138         int rc = 0;
1139
1140         if (!ss_initialized) {
1141                 switch (tclass) {
1142                 case SECCLASS_PROCESS:
1143                         *out_sid = ssid;
1144                         break;
1145                 default:
1146                         *out_sid = tsid;
1147                         break;
1148                 }
1149                 goto out;
1150         }
1151
1152         context_init(&newcontext);
1153
1154         read_lock(&policy_rwlock);
1155
1156         scontext = sidtab_search(&sidtab, ssid);
1157         if (!scontext) {
1158                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1159                        __func__, ssid);
1160                 rc = -EINVAL;
1161                 goto out_unlock;
1162         }
1163         tcontext = sidtab_search(&sidtab, tsid);
1164         if (!tcontext) {
1165                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
1166                        __func__, tsid);
1167                 rc = -EINVAL;
1168                 goto out_unlock;
1169         }
1170
1171         /* Set the user identity. */
1172         switch (specified) {
1173         case AVTAB_TRANSITION:
1174         case AVTAB_CHANGE:
1175                 /* Use the process user identity. */
1176                 newcontext.user = scontext->user;
1177                 break;
1178         case AVTAB_MEMBER:
1179                 /* Use the related object owner. */
1180                 newcontext.user = tcontext->user;
1181                 break;
1182         }
1183
1184         /* Set the role and type to default values. */
1185         switch (tclass) {
1186         case SECCLASS_PROCESS:
1187                 /* Use the current role and type of process. */
1188                 newcontext.role = scontext->role;
1189                 newcontext.type = scontext->type;
1190                 break;
1191         default:
1192                 /* Use the well-defined object role. */
1193                 newcontext.role = OBJECT_R_VAL;
1194                 /* Use the type of the related object. */
1195                 newcontext.type = tcontext->type;
1196         }
1197
1198         /* Look for a type transition/member/change rule. */
1199         avkey.source_type = scontext->type;
1200         avkey.target_type = tcontext->type;
1201         avkey.target_class = tclass;
1202         avkey.specified = specified;
1203         avdatum = avtab_search(&policydb.te_avtab, &avkey);
1204
1205         /* If no permanent rule, also check for enabled conditional rules */
1206         if (!avdatum) {
1207                 node = avtab_search_node(&policydb.te_cond_avtab, &avkey);
1208                 for (; node; node = avtab_search_node_next(node, specified)) {
1209                         if (node->key.specified & AVTAB_ENABLED) {
1210                                 avdatum = &node->datum;
1211                                 break;
1212                         }
1213                 }
1214         }
1215
1216         if (avdatum) {
1217                 /* Use the type from the type transition/member/change rule. */
1218                 newcontext.type = avdatum->data;
1219         }
1220
1221         /* Check for class-specific changes. */
1222         switch (tclass) {
1223         case SECCLASS_PROCESS:
1224                 if (specified & AVTAB_TRANSITION) {
1225                         /* Look for a role transition rule. */
1226                         for (roletr = policydb.role_tr; roletr;
1227                              roletr = roletr->next) {
1228                                 if (roletr->role == scontext->role &&
1229                                     roletr->type == tcontext->type) {
1230                                         /* Use the role transition rule. */
1231                                         newcontext.role = roletr->new_role;
1232                                         break;
1233                                 }
1234                         }
1235                 }
1236                 break;
1237         default:
1238                 break;
1239         }
1240
1241         /* Set the MLS attributes.
1242            This is done last because it may allocate memory. */
1243         rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext);
1244         if (rc)
1245                 goto out_unlock;
1246
1247         /* Check the validity of the context. */
1248         if (!policydb_context_isvalid(&policydb, &newcontext)) {
1249                 rc = compute_sid_handle_invalid_context(scontext,
1250                                                         tcontext,
1251                                                         tclass,
1252                                                         &newcontext);
1253                 if (rc)
1254                         goto out_unlock;
1255         }
1256         /* Obtain the sid for the context. */
1257         rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid);
1258 out_unlock:
1259         read_unlock(&policy_rwlock);
1260         context_destroy(&newcontext);
1261 out:
1262         return rc;
1263 }
1264
1265 /**
1266  * security_transition_sid - Compute the SID for a new subject/object.
1267  * @ssid: source security identifier
1268  * @tsid: target security identifier
1269  * @tclass: target security class
1270  * @out_sid: security identifier for new subject/object
1271  *
1272  * Compute a SID to use for labeling a new subject or object in the
1273  * class @tclass based on a SID pair (@ssid, @tsid).
1274  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1275  * if insufficient memory is available, or %0 if the new SID was
1276  * computed successfully.
1277  */
1278 int security_transition_sid(u32 ssid,
1279                             u32 tsid,
1280                             u16 tclass,
1281                             u32 *out_sid)
1282 {
1283         return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid);
1284 }
1285
1286 /**
1287  * security_member_sid - Compute the SID for member selection.
1288  * @ssid: source security identifier
1289  * @tsid: target security identifier
1290  * @tclass: target security class
1291  * @out_sid: security identifier for selected member
1292  *
1293  * Compute a SID to use when selecting a member of a polyinstantiated
1294  * object of class @tclass based on a SID pair (@ssid, @tsid).
1295  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1296  * if insufficient memory is available, or %0 if the SID was
1297  * computed successfully.
1298  */
1299 int security_member_sid(u32 ssid,
1300                         u32 tsid,
1301                         u16 tclass,
1302                         u32 *out_sid)
1303 {
1304         return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid);
1305 }
1306
1307 /**
1308  * security_change_sid - Compute the SID for object relabeling.
1309  * @ssid: source security identifier
1310  * @tsid: target security identifier
1311  * @tclass: target security class
1312  * @out_sid: security identifier for selected member
1313  *
1314  * Compute a SID to use for relabeling an object of class @tclass
1315  * based on a SID pair (@ssid, @tsid).
1316  * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM
1317  * if insufficient memory is available, or %0 if the SID was
1318  * computed successfully.
1319  */
1320 int security_change_sid(u32 ssid,
1321                         u32 tsid,
1322                         u16 tclass,
1323                         u32 *out_sid)
1324 {
1325         return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid);
1326 }
1327
1328 /*
1329  * Verify that each kernel class that is defined in the
1330  * policy is correct
1331  */
1332 static int validate_classes(struct policydb *p)
1333 {
1334         int i, j;
1335         struct class_datum *cladatum;
1336         struct perm_datum *perdatum;
1337         u32 nprim, tmp, common_pts_len, perm_val, pol_val;
1338         u16 class_val;
1339         const struct selinux_class_perm *kdefs = &selinux_class_perm;
1340         const char *def_class, *def_perm, *pol_class;
1341         struct symtab *perms;
1342         bool print_unknown_handle = 0;
1343
1344         if (p->allow_unknown) {
1345                 u32 num_classes = kdefs->cts_len;
1346                 p->undefined_perms = kcalloc(num_classes, sizeof(u32), GFP_KERNEL);
1347                 if (!p->undefined_perms)
1348                         return -ENOMEM;
1349         }
1350
1351         for (i = 1; i < kdefs->cts_len; i++) {
1352                 def_class = kdefs->class_to_string[i];
1353                 if (!def_class)
1354                         continue;
1355                 if (i > p->p_classes.nprim) {
1356                         printk(KERN_INFO
1357                                "SELinux:  class %s not defined in policy\n",
1358                                def_class);
1359                         if (p->reject_unknown)
1360                                 return -EINVAL;
1361                         if (p->allow_unknown)
1362                                 p->undefined_perms[i-1] = ~0U;
1363                         print_unknown_handle = 1;
1364                         continue;
1365                 }
1366                 pol_class = p->p_class_val_to_name[i-1];
1367                 if (strcmp(pol_class, def_class)) {
1368                         printk(KERN_ERR
1369                                "SELinux:  class %d is incorrect, found %s but should be %s\n",
1370                                i, pol_class, def_class);
1371                         return -EINVAL;
1372                 }
1373         }
1374         for (i = 0; i < kdefs->av_pts_len; i++) {
1375                 class_val = kdefs->av_perm_to_string[i].tclass;
1376                 perm_val = kdefs->av_perm_to_string[i].value;
1377                 def_perm = kdefs->av_perm_to_string[i].name;
1378                 if (class_val > p->p_classes.nprim)
1379                         continue;
1380                 pol_class = p->p_class_val_to_name[class_val-1];
1381                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1382                 BUG_ON(!cladatum);
1383                 perms = &cladatum->permissions;
1384                 nprim = 1 << (perms->nprim - 1);
1385                 if (perm_val > nprim) {
1386                         printk(KERN_INFO
1387                                "SELinux:  permission %s in class %s not defined in policy\n",
1388                                def_perm, pol_class);
1389                         if (p->reject_unknown)
1390                                 return -EINVAL;
1391                         if (p->allow_unknown)
1392                                 p->undefined_perms[class_val-1] |= perm_val;
1393                         print_unknown_handle = 1;
1394                         continue;
1395                 }
1396                 perdatum = hashtab_search(perms->table, def_perm);
1397                 if (perdatum == NULL) {
1398                         printk(KERN_ERR
1399                                "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1400                                def_perm, pol_class);
1401                         return -EINVAL;
1402                 }
1403                 pol_val = 1 << (perdatum->value - 1);
1404                 if (pol_val != perm_val) {
1405                         printk(KERN_ERR
1406                                "SELinux:  permission %s in class %s has incorrect value\n",
1407                                def_perm, pol_class);
1408                         return -EINVAL;
1409                 }
1410         }
1411         for (i = 0; i < kdefs->av_inherit_len; i++) {
1412                 class_val = kdefs->av_inherit[i].tclass;
1413                 if (class_val > p->p_classes.nprim)
1414                         continue;
1415                 pol_class = p->p_class_val_to_name[class_val-1];
1416                 cladatum = hashtab_search(p->p_classes.table, pol_class);
1417                 BUG_ON(!cladatum);
1418                 if (!cladatum->comdatum) {
1419                         printk(KERN_ERR
1420                                "SELinux:  class %s should have an inherits clause but does not\n",
1421                                pol_class);
1422                         return -EINVAL;
1423                 }
1424                 tmp = kdefs->av_inherit[i].common_base;
1425                 common_pts_len = 0;
1426                 while (!(tmp & 0x01)) {
1427                         common_pts_len++;
1428                         tmp >>= 1;
1429                 }
1430                 perms = &cladatum->comdatum->permissions;
1431                 for (j = 0; j < common_pts_len; j++) {
1432                         def_perm = kdefs->av_inherit[i].common_pts[j];
1433                         if (j >= perms->nprim) {
1434                                 printk(KERN_INFO
1435                                        "SELinux:  permission %s in class %s not defined in policy\n",
1436                                        def_perm, pol_class);
1437                                 if (p->reject_unknown)
1438                                         return -EINVAL;
1439                                 if (p->allow_unknown)
1440                                         p->undefined_perms[class_val-1] |= (1 << j);
1441                                 print_unknown_handle = 1;
1442                                 continue;
1443                         }
1444                         perdatum = hashtab_search(perms->table, def_perm);
1445                         if (perdatum == NULL) {
1446                                 printk(KERN_ERR
1447                                        "SELinux:  permission %s in class %s not found in policy, bad policy\n",
1448                                        def_perm, pol_class);
1449                                 return -EINVAL;
1450                         }
1451                         if (perdatum->value != j + 1) {
1452                                 printk(KERN_ERR
1453                                        "SELinux:  permission %s in class %s has incorrect value\n",
1454                                        def_perm, pol_class);
1455                                 return -EINVAL;
1456                         }
1457                 }
1458         }
1459         if (print_unknown_handle)
1460                 printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n",
1461                         (security_get_allow_unknown() ? "allowed" : "denied"));
1462         return 0;
1463 }
1464
1465 /* Clone the SID into the new SID table. */
1466 static int clone_sid(u32 sid,
1467                      struct context *context,
1468                      void *arg)
1469 {
1470         struct sidtab *s = arg;
1471
1472         return sidtab_insert(s, sid, context);
1473 }
1474
1475 static inline int convert_context_handle_invalid_context(struct context *context)
1476 {
1477         int rc = 0;
1478
1479         if (selinux_enforcing) {
1480                 rc = -EINVAL;
1481         } else {
1482                 char *s;
1483                 u32 len;
1484
1485                 if (!context_struct_to_string(context, &s, &len)) {
1486                         printk(KERN_WARNING
1487                        "SELinux:  Context %s would be invalid if enforcing\n",
1488                                s);
1489                         kfree(s);
1490                 }
1491         }
1492         return rc;
1493 }
1494
1495 struct convert_context_args {
1496         struct policydb *oldp;
1497         struct policydb *newp;
1498 };
1499
1500 /*
1501  * Convert the values in the security context
1502  * structure `c' from the values specified
1503  * in the policy `p->oldp' to the values specified
1504  * in the policy `p->newp'.  Verify that the
1505  * context is valid under the new policy.
1506  */
1507 static int convert_context(u32 key,
1508                            struct context *c,
1509                            void *p)
1510 {
1511         struct convert_context_args *args;
1512         struct context oldc;
1513         struct role_datum *role;
1514         struct type_datum *typdatum;
1515         struct user_datum *usrdatum;
1516         char *s;
1517         u32 len;
1518         int rc;
1519
1520         args = p;
1521
1522         if (c->str) {
1523                 struct context ctx;
1524                 s = kstrdup(c->str, GFP_KERNEL);
1525                 if (!s) {
1526                         rc = -ENOMEM;
1527                         goto out;
1528                 }
1529                 rc = string_to_context_struct(args->newp, NULL, s,
1530                                               c->len, &ctx, SECSID_NULL);
1531                 kfree(s);
1532                 if (!rc) {
1533                         printk(KERN_INFO
1534                        "SELinux:  Context %s became valid (mapped).\n",
1535                                c->str);
1536                         /* Replace string with mapped representation. */
1537                         kfree(c->str);
1538                         memcpy(c, &ctx, sizeof(*c));
1539                         goto out;
1540                 } else if (rc == -EINVAL) {
1541                         /* Retain string representation for later mapping. */
1542                         rc = 0;
1543                         goto out;
1544                 } else {
1545                         /* Other error condition, e.g. ENOMEM. */
1546                         printk(KERN_ERR
1547                        "SELinux:   Unable to map context %s, rc = %d.\n",
1548                                c->str, -rc);
1549                         goto out;
1550                 }
1551         }
1552
1553         rc = context_cpy(&oldc, c);
1554         if (rc)
1555                 goto out;
1556
1557         rc = -EINVAL;
1558
1559         /* Convert the user. */
1560         usrdatum = hashtab_search(args->newp->p_users.table,
1561                                   args->oldp->p_user_val_to_name[c->user - 1]);
1562         if (!usrdatum)
1563                 goto bad;
1564         c->user = usrdatum->value;
1565
1566         /* Convert the role. */
1567         role = hashtab_search(args->newp->p_roles.table,
1568                               args->oldp->p_role_val_to_name[c->role - 1]);
1569         if (!role)
1570                 goto bad;
1571         c->role = role->value;
1572
1573         /* Convert the type. */
1574         typdatum = hashtab_search(args->newp->p_types.table,
1575                                   args->oldp->p_type_val_to_name[c->type - 1]);
1576         if (!typdatum)
1577                 goto bad;
1578         c->type = typdatum->value;
1579
1580         rc = mls_convert_context(args->oldp, args->newp, c);
1581         if (rc)
1582                 goto bad;
1583
1584         /* Check the validity of the new context. */
1585         if (!policydb_context_isvalid(args->newp, c)) {
1586                 rc = convert_context_handle_invalid_context(&oldc);
1587                 if (rc)
1588                         goto bad;
1589         }
1590
1591         context_destroy(&oldc);
1592         rc = 0;
1593 out:
1594         return rc;
1595 bad:
1596         /* Map old representation to string and save it. */
1597         if (context_struct_to_string(&oldc, &s, &len))
1598                 return -ENOMEM;
1599         context_destroy(&oldc);
1600         context_destroy(c);
1601         c->str = s;
1602         c->len = len;
1603         printk(KERN_INFO
1604                "SELinux:  Context %s became invalid (unmapped).\n",
1605                c->str);
1606         rc = 0;
1607         goto out;
1608 }
1609
1610 static void security_load_policycaps(void)
1611 {
1612         selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps,
1613                                                   POLICYDB_CAPABILITY_NETPEER);
1614         selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps,
1615                                                   POLICYDB_CAPABILITY_OPENPERM);
1616 }
1617
1618 extern void selinux_complete_init(void);
1619 static int security_preserve_bools(struct policydb *p);
1620
1621 /**
1622  * security_load_policy - Load a security policy configuration.
1623  * @data: binary policy data
1624  * @len: length of data in bytes
1625  *
1626  * Load a new set of security policy configuration data,
1627  * validate it and convert the SID table as necessary.
1628  * This function will flush the access vector cache after
1629  * loading the new policy.
1630  */
1631 int security_load_policy(void *data, size_t len)
1632 {
1633         struct policydb oldpolicydb, newpolicydb;
1634         struct sidtab oldsidtab, newsidtab;
1635         struct convert_context_args args;
1636         u32 seqno;
1637         int rc = 0;
1638         struct policy_file file = { data, len }, *fp = &file;
1639
1640         if (!ss_initialized) {
1641                 avtab_cache_init();
1642                 if (policydb_read(&policydb, fp)) {
1643                         avtab_cache_destroy();
1644                         return -EINVAL;
1645                 }
1646                 if (policydb_load_isids(&policydb, &sidtab)) {
1647                         policydb_destroy(&policydb);
1648                         avtab_cache_destroy();
1649                         return -EINVAL;
1650                 }
1651                 /* Verify that the kernel defined classes are correct. */
1652                 if (validate_classes(&policydb)) {
1653                         printk(KERN_ERR
1654                                "SELinux:  the definition of a class is incorrect\n");
1655                         sidtab_destroy(&sidtab);
1656                         policydb_destroy(&policydb);
1657                         avtab_cache_destroy();
1658                         return -EINVAL;
1659                 }
1660                 security_load_policycaps();
1661                 policydb_loaded_version = policydb.policyvers;
1662                 ss_initialized = 1;
1663                 seqno = ++latest_granting;
1664                 selinux_complete_init();
1665                 avc_ss_reset(seqno);
1666                 selnl_notify_policyload(seqno);
1667                 selinux_netlbl_cache_invalidate();
1668                 selinux_xfrm_notify_policyload();
1669                 return 0;
1670         }
1671
1672 #if 0
1673         sidtab_hash_eval(&sidtab, "sids");
1674 #endif
1675
1676         if (policydb_read(&newpolicydb, fp))
1677                 return -EINVAL;
1678
1679         if (sidtab_init(&newsidtab)) {
1680                 policydb_destroy(&newpolicydb);
1681                 return -ENOMEM;
1682         }
1683
1684         /* Verify that the kernel defined classes are correct. */
1685         if (validate_classes(&newpolicydb)) {
1686                 printk(KERN_ERR
1687                        "SELinux:  the definition of a class is incorrect\n");
1688                 rc = -EINVAL;
1689                 goto err;
1690         }
1691
1692         rc = security_preserve_bools(&newpolicydb);
1693         if (rc) {
1694                 printk(KERN_ERR "SELinux:  unable to preserve booleans\n");
1695                 goto err;
1696         }
1697
1698         /* Clone the SID table. */
1699         sidtab_shutdown(&sidtab);
1700         if (sidtab_map(&sidtab, clone_sid, &newsidtab)) {
1701                 rc = -ENOMEM;
1702                 goto err;
1703         }
1704
1705         /*
1706          * Convert the internal representations of contexts
1707          * in the new SID table.
1708          */
1709         args.oldp = &policydb;
1710         args.newp = &newpolicydb;
1711         rc = sidtab_map(&newsidtab, convert_context, &args);
1712         if (rc)
1713                 goto err;
1714
1715         /* Save the old policydb and SID table to free later. */
1716         memcpy(&oldpolicydb, &policydb, sizeof policydb);
1717         sidtab_set(&oldsidtab, &sidtab);
1718
1719         /* Install the new policydb and SID table. */
1720         write_lock_irq(&policy_rwlock);
1721         memcpy(&policydb, &newpolicydb, sizeof policydb);
1722         sidtab_set(&sidtab, &newsidtab);
1723         security_load_policycaps();
1724         seqno = ++latest_granting;
1725         policydb_loaded_version = policydb.policyvers;
1726         write_unlock_irq(&policy_rwlock);
1727
1728         /* Free the old policydb and SID table. */
1729         policydb_destroy(&oldpolicydb);
1730         sidtab_destroy(&oldsidtab);
1731
1732         avc_ss_reset(seqno);
1733         selnl_notify_policyload(seqno);
1734         selinux_netlbl_cache_invalidate();
1735         selinux_xfrm_notify_policyload();
1736
1737         return 0;
1738
1739 err:
1740         sidtab_destroy(&newsidtab);
1741         policydb_destroy(&newpolicydb);
1742         return rc;
1743
1744 }
1745
1746 /**
1747  * security_port_sid - Obtain the SID for a port.
1748  * @protocol: protocol number
1749  * @port: port number
1750  * @out_sid: security identifier
1751  */
1752 int security_port_sid(u8 protocol, u16 port, u32 *out_sid)
1753 {
1754         struct ocontext *c;
1755         int rc = 0;
1756
1757         read_lock(&policy_rwlock);
1758
1759         c = policydb.ocontexts[OCON_PORT];
1760         while (c) {
1761                 if (c->u.port.protocol == protocol &&
1762                     c->u.port.low_port <= port &&
1763                     c->u.port.high_port >= port)
1764                         break;
1765                 c = c->next;
1766         }
1767
1768         if (c) {
1769                 if (!c->sid[0]) {
1770                         rc = sidtab_context_to_sid(&sidtab,
1771                                                    &c->context[0],
1772                                                    &c->sid[0]);
1773                         if (rc)
1774                                 goto out;
1775                 }
1776                 *out_sid = c->sid[0];
1777         } else {
1778                 *out_sid = SECINITSID_PORT;
1779         }
1780
1781 out:
1782         read_unlock(&policy_rwlock);
1783         return rc;
1784 }
1785
1786 /**
1787  * security_netif_sid - Obtain the SID for a network interface.
1788  * @name: interface name
1789  * @if_sid: interface SID
1790  */
1791 int security_netif_sid(char *name, u32 *if_sid)
1792 {
1793         int rc = 0;
1794         struct ocontext *c;
1795
1796         read_lock(&policy_rwlock);
1797
1798         c = policydb.ocontexts[OCON_NETIF];
1799         while (c) {
1800                 if (strcmp(name, c->u.name) == 0)
1801                         break;
1802                 c = c->next;
1803         }
1804
1805         if (c) {
1806                 if (!c->sid[0] || !c->sid[1]) {
1807                         rc = sidtab_context_to_sid(&sidtab,
1808                                                   &c->context[0],
1809                                                   &c->sid[0]);
1810                         if (rc)
1811                                 goto out;
1812                         rc = sidtab_context_to_sid(&sidtab,
1813                                                    &c->context[1],
1814                                                    &c->sid[1]);
1815                         if (rc)
1816                                 goto out;
1817                 }
1818                 *if_sid = c->sid[0];
1819         } else
1820                 *if_sid = SECINITSID_NETIF;
1821
1822 out:
1823         read_unlock(&policy_rwlock);
1824         return rc;
1825 }
1826
1827 static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask)
1828 {
1829         int i, fail = 0;
1830
1831         for (i = 0; i < 4; i++)
1832                 if (addr[i] != (input[i] & mask[i])) {
1833                         fail = 1;
1834                         break;
1835                 }
1836
1837         return !fail;
1838 }
1839
1840 /**
1841  * security_node_sid - Obtain the SID for a node (host).
1842  * @domain: communication domain aka address family
1843  * @addrp: address
1844  * @addrlen: address length in bytes
1845  * @out_sid: security identifier
1846  */
1847 int security_node_sid(u16 domain,
1848                       void *addrp,
1849                       u32 addrlen,
1850                       u32 *out_sid)
1851 {
1852         int rc = 0;
1853         struct ocontext *c;
1854
1855         read_lock(&policy_rwlock);
1856
1857         switch (domain) {
1858         case AF_INET: {
1859                 u32 addr;
1860
1861                 if (addrlen != sizeof(u32)) {
1862                         rc = -EINVAL;
1863                         goto out;
1864                 }
1865
1866                 addr = *((u32 *)addrp);
1867
1868                 c = policydb.ocontexts[OCON_NODE];
1869                 while (c) {
1870                         if (c->u.node.addr == (addr & c->u.node.mask))
1871                                 break;
1872                         c = c->next;
1873                 }
1874                 break;
1875         }
1876
1877         case AF_INET6:
1878                 if (addrlen != sizeof(u64) * 2) {
1879                         rc = -EINVAL;
1880                         goto out;
1881                 }
1882                 c = policydb.ocontexts[OCON_NODE6];
1883                 while (c) {
1884                         if (match_ipv6_addrmask(addrp, c->u.node6.addr,
1885                                                 c->u.node6.mask))
1886                                 break;
1887                         c = c->next;
1888                 }
1889                 break;
1890
1891         default:
1892                 *out_sid = SECINITSID_NODE;
1893                 goto out;
1894         }
1895
1896         if (c) {
1897                 if (!c->sid[0]) {
1898                         rc = sidtab_context_to_sid(&sidtab,
1899                                                    &c->context[0],
1900                                                    &c->sid[0]);
1901                         if (rc)
1902                                 goto out;
1903                 }
1904                 *out_sid = c->sid[0];
1905         } else {
1906                 *out_sid = SECINITSID_NODE;
1907         }
1908
1909 out:
1910         read_unlock(&policy_rwlock);
1911         return rc;
1912 }
1913
1914 #define SIDS_NEL 25
1915
1916 /**
1917  * security_get_user_sids - Obtain reachable SIDs for a user.
1918  * @fromsid: starting SID
1919  * @username: username
1920  * @sids: array of reachable SIDs for user
1921  * @nel: number of elements in @sids
1922  *
1923  * Generate the set of SIDs for legal security contexts
1924  * for a given user that can be reached by @fromsid.
1925  * Set *@sids to point to a dynamically allocated
1926  * array containing the set of SIDs.  Set *@nel to the
1927  * number of elements in the array.
1928  */
1929
1930 int security_get_user_sids(u32 fromsid,
1931                            char *username,
1932                            u32 **sids,
1933                            u32 *nel)
1934 {
1935         struct context *fromcon, usercon;
1936         u32 *mysids = NULL, *mysids2, sid;
1937         u32 mynel = 0, maxnel = SIDS_NEL;
1938         struct user_datum *user;
1939         struct role_datum *role;
1940         struct ebitmap_node *rnode, *tnode;
1941         int rc = 0, i, j;
1942
1943         *sids = NULL;
1944         *nel = 0;
1945
1946         if (!ss_initialized)
1947                 goto out;
1948
1949         read_lock(&policy_rwlock);
1950
1951         context_init(&usercon);
1952
1953         fromcon = sidtab_search(&sidtab, fromsid);
1954         if (!fromcon) {
1955                 rc = -EINVAL;
1956                 goto out_unlock;
1957         }
1958
1959         user = hashtab_search(policydb.p_users.table, username);
1960         if (!user) {
1961                 rc = -EINVAL;
1962                 goto out_unlock;
1963         }
1964         usercon.user = user->value;
1965
1966         mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC);
1967         if (!mysids) {
1968                 rc = -ENOMEM;
1969                 goto out_unlock;
1970         }
1971
1972         ebitmap_for_each_positive_bit(&user->roles, rnode, i) {
1973                 role = policydb.role_val_to_struct[i];
1974                 usercon.role = i+1;
1975                 ebitmap_for_each_positive_bit(&role->types, tnode, j) {
1976                         usercon.type = j+1;
1977
1978                         if (mls_setup_user_range(fromcon, user, &usercon))
1979                                 continue;
1980
1981                         rc = sidtab_context_to_sid(&sidtab, &usercon, &sid);
1982                         if (rc)
1983                                 goto out_unlock;
1984                         if (mynel < maxnel) {
1985                                 mysids[mynel++] = sid;
1986                         } else {
1987                                 maxnel += SIDS_NEL;
1988                                 mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC);
1989                                 if (!mysids2) {
1990                                         rc = -ENOMEM;
1991                                         goto out_unlock;
1992                                 }
1993                                 memcpy(mysids2, mysids, mynel * sizeof(*mysids2));
1994                                 kfree(mysids);
1995                                 mysids = mysids2;
1996                                 mysids[mynel++] = sid;
1997                         }
1998                 }
1999         }
2000
2001 out_unlock:
2002         read_unlock(&policy_rwlock);
2003         if (rc || !mynel) {
2004                 kfree(mysids);
2005                 goto out;
2006         }
2007
2008         mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL);
2009         if (!mysids2) {
2010                 rc = -ENOMEM;
2011                 kfree(mysids);
2012                 goto out;
2013         }
2014         for (i = 0, j = 0; i < mynel; i++) {
2015                 rc = avc_has_perm_noaudit(fromsid, mysids[i],
2016                                           SECCLASS_PROCESS,
2017                                           PROCESS__TRANSITION, AVC_STRICT,
2018                                           NULL);
2019                 if (!rc)
2020                         mysids2[j++] = mysids[i];
2021                 cond_resched();
2022         }
2023         rc = 0;
2024         kfree(mysids);
2025         *sids = mysids2;
2026         *nel = j;
2027 out:
2028         return rc;
2029 }
2030
2031 /**
2032  * security_genfs_sid - Obtain a SID for a file in a filesystem
2033  * @fstype: filesystem type
2034  * @path: path from root of mount
2035  * @sclass: file security class
2036  * @sid: SID for path
2037  *
2038  * Obtain a SID to use for a file in a filesystem that
2039  * cannot support xattr or use a fixed labeling behavior like
2040  * transition SIDs or task SIDs.
2041  */
2042 int security_genfs_sid(const char *fstype,
2043                        char *path,
2044                        u16 sclass,
2045                        u32 *sid)
2046 {
2047         int len;
2048         struct genfs *genfs;
2049         struct ocontext *c;
2050         int rc = 0, cmp = 0;
2051
2052         while (path[0] == '/' && path[1] == '/')
2053                 path++;
2054
2055         read_lock(&policy_rwlock);
2056
2057         for (genfs = policydb.genfs; genfs; genfs = genfs->next) {
2058                 cmp = strcmp(fstype, genfs->fstype);
2059                 if (cmp <= 0)
2060                         break;
2061         }
2062
2063         if (!genfs || cmp) {
2064                 *sid = SECINITSID_UNLABELED;
2065                 rc = -ENOENT;
2066                 goto out;
2067         }
2068
2069         for (c = genfs->head; c; c = c->next) {
2070                 len = strlen(c->u.name);
2071                 if ((!c->v.sclass || sclass == c->v.sclass) &&
2072                     (strncmp(c->u.name, path, len) == 0))
2073                         break;
2074         }
2075
2076         if (!c) {
2077                 *sid = SECINITSID_UNLABELED;
2078                 rc = -ENOENT;
2079                 goto out;
2080         }
2081
2082         if (!c->sid[0]) {
2083                 rc = sidtab_context_to_sid(&sidtab,
2084                                            &c->context[0],
2085                                            &c->sid[0]);
2086                 if (rc)
2087                         goto out;
2088         }
2089
2090         *sid = c->sid[0];
2091 out:
2092         read_unlock(&policy_rwlock);
2093         return rc;
2094 }
2095
2096 /**
2097  * security_fs_use - Determine how to handle labeling for a filesystem.
2098  * @fstype: filesystem type
2099  * @behavior: labeling behavior
2100  * @sid: SID for filesystem (superblock)
2101  */
2102 int security_fs_use(
2103         const char *fstype,
2104         unsigned int *behavior,
2105         u32 *sid)
2106 {
2107         int rc = 0;
2108         struct ocontext *c;
2109
2110         read_lock(&policy_rwlock);
2111
2112         c = policydb.ocontexts[OCON_FSUSE];
2113         while (c) {
2114                 if (strcmp(fstype, c->u.name) == 0)
2115                         break;
2116                 c = c->next;
2117         }
2118
2119         if (c) {
2120                 *behavior = c->v.behavior;
2121                 if (!c->sid[0]) {
2122                         rc = sidtab_context_to_sid(&sidtab,
2123                                                    &c->context[0],
2124                                                    &c->sid[0]);
2125                         if (rc)
2126                                 goto out;
2127                 }
2128                 *sid = c->sid[0];
2129         } else {
2130                 rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid);
2131                 if (rc) {
2132                         *behavior = SECURITY_FS_USE_NONE;
2133                         rc = 0;
2134                 } else {
2135                         *behavior = SECURITY_FS_USE_GENFS;
2136                 }
2137         }
2138
2139 out:
2140         read_unlock(&policy_rwlock);
2141         return rc;
2142 }
2143
2144 int security_get_bools(int *len, char ***names, int **values)
2145 {
2146         int i, rc = -ENOMEM;
2147
2148         read_lock(&policy_rwlock);
2149         *names = NULL;
2150         *values = NULL;
2151
2152         *len = policydb.p_bools.nprim;
2153         if (!*len) {
2154                 rc = 0;
2155                 goto out;
2156         }
2157
2158        *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC);
2159         if (!*names)
2160                 goto err;
2161
2162        *values = kcalloc(*len, sizeof(int), GFP_ATOMIC);
2163         if (!*values)
2164                 goto err;
2165
2166         for (i = 0; i < *len; i++) {
2167                 size_t name_len;
2168                 (*values)[i] = policydb.bool_val_to_struct[i]->state;
2169                 name_len = strlen(policydb.p_bool_val_to_name[i]) + 1;
2170                (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC);
2171                 if (!(*names)[i])
2172                         goto err;
2173                 strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len);
2174                 (*names)[i][name_len - 1] = 0;
2175         }
2176         rc = 0;
2177 out:
2178         read_unlock(&policy_rwlock);
2179         return rc;
2180 err:
2181         if (*names) {
2182                 for (i = 0; i < *len; i++)
2183                         kfree((*names)[i]);
2184         }
2185         kfree(*values);
2186         goto out;
2187 }
2188
2189
2190 int security_set_bools(int len, int *values)
2191 {
2192         int i, rc = 0;
2193         int lenp, seqno = 0;
2194         struct cond_node *cur;
2195
2196         write_lock_irq(&policy_rwlock);
2197
2198         lenp = policydb.p_bools.nprim;
2199         if (len != lenp) {
2200                 rc = -EFAULT;
2201                 goto out;
2202         }
2203
2204         for (i = 0; i < len; i++) {
2205                 if (!!values[i] != policydb.bool_val_to_struct[i]->state) {
2206                         audit_log(current->audit_context, GFP_ATOMIC,
2207                                 AUDIT_MAC_CONFIG_CHANGE,
2208                                 "bool=%s val=%d old_val=%d auid=%u ses=%u",
2209                                 policydb.p_bool_val_to_name[i],
2210                                 !!values[i],
2211                                 policydb.bool_val_to_struct[i]->state,
2212                                 audit_get_loginuid(current),
2213                                 audit_get_sessionid(current));
2214                 }
2215                 if (values[i])
2216                         policydb.bool_val_to_struct[i]->state = 1;
2217                 else
2218                         policydb.bool_val_to_struct[i]->state = 0;
2219         }
2220
2221         for (cur = policydb.cond_list; cur; cur = cur->next) {
2222                 rc = evaluate_cond_node(&policydb, cur);
2223                 if (rc)
2224                         goto out;
2225         }
2226
2227         seqno = ++latest_granting;
2228
2229 out:
2230         write_unlock_irq(&policy_rwlock);
2231         if (!rc) {
2232                 avc_ss_reset(seqno);
2233                 selnl_notify_policyload(seqno);
2234                 selinux_xfrm_notify_policyload();
2235         }
2236         return rc;
2237 }
2238
2239 int security_get_bool_value(int bool)
2240 {
2241         int rc = 0;
2242         int len;
2243
2244         read_lock(&policy_rwlock);
2245
2246         len = policydb.p_bools.nprim;
2247         if (bool >= len) {
2248                 rc = -EFAULT;
2249                 goto out;
2250         }
2251
2252         rc = policydb.bool_val_to_struct[bool]->state;
2253 out:
2254         read_unlock(&policy_rwlock);
2255         return rc;
2256 }
2257
2258 static int security_preserve_bools(struct policydb *p)
2259 {
2260         int rc, nbools = 0, *bvalues = NULL, i;
2261         char **bnames = NULL;
2262         struct cond_bool_datum *booldatum;
2263         struct cond_node *cur;
2264
2265         rc = security_get_bools(&nbools, &bnames, &bvalues);
2266         if (rc)
2267                 goto out;
2268         for (i = 0; i < nbools; i++) {
2269                 booldatum = hashtab_search(p->p_bools.table, bnames[i]);
2270                 if (booldatum)
2271                         booldatum->state = bvalues[i];
2272         }
2273         for (cur = p->cond_list; cur; cur = cur->next) {
2274                 rc = evaluate_cond_node(p, cur);
2275                 if (rc)
2276                         goto out;
2277         }
2278
2279 out:
2280         if (bnames) {
2281                 for (i = 0; i < nbools; i++)
2282                         kfree(bnames[i]);
2283         }
2284         kfree(bnames);
2285         kfree(bvalues);
2286         return rc;
2287 }
2288
2289 /*
2290  * security_sid_mls_copy() - computes a new sid based on the given
2291  * sid and the mls portion of mls_sid.
2292  */
2293 int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid)
2294 {
2295         struct context *context1;
2296         struct context *context2;
2297         struct context newcon;
2298         char *s;
2299         u32 len;
2300         int rc = 0;
2301
2302         if (!ss_initialized || !selinux_mls_enabled) {
2303                 *new_sid = sid;
2304                 goto out;
2305         }
2306
2307         context_init(&newcon);
2308
2309         read_lock(&policy_rwlock);
2310         context1 = sidtab_search(&sidtab, sid);
2311         if (!context1) {
2312                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2313                         __func__, sid);
2314                 rc = -EINVAL;
2315                 goto out_unlock;
2316         }
2317
2318         context2 = sidtab_search(&sidtab, mls_sid);
2319         if (!context2) {
2320                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2321                         __func__, mls_sid);
2322                 rc = -EINVAL;
2323                 goto out_unlock;
2324         }
2325
2326         newcon.user = context1->user;
2327         newcon.role = context1->role;
2328         newcon.type = context1->type;
2329         rc = mls_context_cpy(&newcon, context2);
2330         if (rc)
2331                 goto out_unlock;
2332
2333         /* Check the validity of the new context. */
2334         if (!policydb_context_isvalid(&policydb, &newcon)) {
2335                 rc = convert_context_handle_invalid_context(&newcon);
2336                 if (rc)
2337                         goto bad;
2338         }
2339
2340         rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid);
2341         goto out_unlock;
2342
2343 bad:
2344         if (!context_struct_to_string(&newcon, &s, &len)) {
2345                 audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2346                           "security_sid_mls_copy: invalid context %s", s);
2347                 kfree(s);
2348         }
2349
2350 out_unlock:
2351         read_unlock(&policy_rwlock);
2352         context_destroy(&newcon);
2353 out:
2354         return rc;
2355 }
2356
2357 /**
2358  * security_net_peersid_resolve - Compare and resolve two network peer SIDs
2359  * @nlbl_sid: NetLabel SID
2360  * @nlbl_type: NetLabel labeling protocol type
2361  * @xfrm_sid: XFRM SID
2362  *
2363  * Description:
2364  * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be
2365  * resolved into a single SID it is returned via @peer_sid and the function
2366  * returns zero.  Otherwise @peer_sid is set to SECSID_NULL and the function
2367  * returns a negative value.  A table summarizing the behavior is below:
2368  *
2369  *                                 | function return |      @sid
2370  *   ------------------------------+-----------------+-----------------
2371  *   no peer labels                |        0        |    SECSID_NULL
2372  *   single peer label             |        0        |    <peer_label>
2373  *   multiple, consistent labels   |        0        |    <peer_label>
2374  *   multiple, inconsistent labels |    -<errno>     |    SECSID_NULL
2375  *
2376  */
2377 int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type,
2378                                  u32 xfrm_sid,
2379                                  u32 *peer_sid)
2380 {
2381         int rc;
2382         struct context *nlbl_ctx;
2383         struct context *xfrm_ctx;
2384
2385         /* handle the common (which also happens to be the set of easy) cases
2386          * right away, these two if statements catch everything involving a
2387          * single or absent peer SID/label */
2388         if (xfrm_sid == SECSID_NULL) {
2389                 *peer_sid = nlbl_sid;
2390                 return 0;
2391         }
2392         /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label
2393          * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label
2394          * is present */
2395         if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) {
2396                 *peer_sid = xfrm_sid;
2397                 return 0;
2398         }
2399
2400         /* we don't need to check ss_initialized here since the only way both
2401          * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the
2402          * security server was initialized and ss_initialized was true */
2403         if (!selinux_mls_enabled) {
2404                 *peer_sid = SECSID_NULL;
2405                 return 0;
2406         }
2407
2408         read_lock(&policy_rwlock);
2409
2410         nlbl_ctx = sidtab_search(&sidtab, nlbl_sid);
2411         if (!nlbl_ctx) {
2412                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2413                        __func__, nlbl_sid);
2414                 rc = -EINVAL;
2415                 goto out_slowpath;
2416         }
2417         xfrm_ctx = sidtab_search(&sidtab, xfrm_sid);
2418         if (!xfrm_ctx) {
2419                 printk(KERN_ERR "SELinux: %s:  unrecognized SID %d\n",
2420                        __func__, xfrm_sid);
2421                 rc = -EINVAL;
2422                 goto out_slowpath;
2423         }
2424         rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES);
2425
2426 out_slowpath:
2427         read_unlock(&policy_rwlock);
2428         if (rc == 0)
2429                 /* at present NetLabel SIDs/labels really only carry MLS
2430                  * information so if the MLS portion of the NetLabel SID
2431                  * matches the MLS portion of the labeled XFRM SID/label
2432                  * then pass along the XFRM SID as it is the most
2433                  * expressive */
2434                 *peer_sid = xfrm_sid;
2435         else
2436                 *peer_sid = SECSID_NULL;
2437         return rc;
2438 }
2439
2440 static int get_classes_callback(void *k, void *d, void *args)
2441 {
2442         struct class_datum *datum = d;
2443         char *name = k, **classes = args;
2444         int value = datum->value - 1;
2445
2446         classes[value] = kstrdup(name, GFP_ATOMIC);
2447         if (!classes[value])
2448                 return -ENOMEM;
2449
2450         return 0;
2451 }
2452
2453 int security_get_classes(char ***classes, int *nclasses)
2454 {
2455         int rc = -ENOMEM;
2456
2457         read_lock(&policy_rwlock);
2458
2459         *nclasses = policydb.p_classes.nprim;
2460         *classes = kcalloc(*nclasses, sizeof(*classes), GFP_ATOMIC);
2461         if (!*classes)
2462                 goto out;
2463
2464         rc = hashtab_map(policydb.p_classes.table, get_classes_callback,
2465                         *classes);
2466         if (rc < 0) {
2467                 int i;
2468                 for (i = 0; i < *nclasses; i++)
2469                         kfree((*classes)[i]);
2470                 kfree(*classes);
2471         }
2472
2473 out:
2474         read_unlock(&policy_rwlock);
2475         return rc;
2476 }
2477
2478 static int get_permissions_callback(void *k, void *d, void *args)
2479 {
2480         struct perm_datum *datum = d;
2481         char *name = k, **perms = args;
2482         int value = datum->value - 1;
2483
2484         perms[value] = kstrdup(name, GFP_ATOMIC);
2485         if (!perms[value])
2486                 return -ENOMEM;
2487
2488         return 0;
2489 }
2490
2491 int security_get_permissions(char *class, char ***perms, int *nperms)
2492 {
2493         int rc = -ENOMEM, i;
2494         struct class_datum *match;
2495
2496         read_lock(&policy_rwlock);
2497
2498         match = hashtab_search(policydb.p_classes.table, class);
2499         if (!match) {
2500                 printk(KERN_ERR "SELinux: %s:  unrecognized class %s\n",
2501                         __func__, class);
2502                 rc = -EINVAL;
2503                 goto out;
2504         }
2505
2506         *nperms = match->permissions.nprim;
2507         *perms = kcalloc(*nperms, sizeof(*perms), GFP_ATOMIC);
2508         if (!*perms)
2509                 goto out;
2510
2511         if (match->comdatum) {
2512                 rc = hashtab_map(match->comdatum->permissions.table,
2513                                 get_permissions_callback, *perms);
2514                 if (rc < 0)
2515                         goto err;
2516         }
2517
2518         rc = hashtab_map(match->permissions.table, get_permissions_callback,
2519                         *perms);
2520         if (rc < 0)
2521                 goto err;
2522
2523 out:
2524         read_unlock(&policy_rwlock);
2525         return rc;
2526
2527 err:
2528         read_unlock(&policy_rwlock);
2529         for (i = 0; i < *nperms; i++)
2530                 kfree((*perms)[i]);
2531         kfree(*perms);
2532         return rc;
2533 }
2534
2535 int security_get_reject_unknown(void)
2536 {
2537         return policydb.reject_unknown;
2538 }
2539
2540 int security_get_allow_unknown(void)
2541 {
2542         return policydb.allow_unknown;
2543 }
2544
2545 /**
2546  * security_policycap_supported - Check for a specific policy capability
2547  * @req_cap: capability
2548  *
2549  * Description:
2550  * This function queries the currently loaded policy to see if it supports the
2551  * capability specified by @req_cap.  Returns true (1) if the capability is
2552  * supported, false (0) if it isn't supported.
2553  *
2554  */
2555 int security_policycap_supported(unsigned int req_cap)
2556 {
2557         int rc;
2558
2559         read_lock(&policy_rwlock);
2560         rc = ebitmap_get_bit(&policydb.policycaps, req_cap);
2561         read_unlock(&policy_rwlock);
2562
2563         return rc;
2564 }
2565
2566 struct selinux_audit_rule {
2567         u32 au_seqno;
2568         struct context au_ctxt;
2569 };
2570
2571 void selinux_audit_rule_free(void *vrule)
2572 {
2573         struct selinux_audit_rule *rule = vrule;
2574
2575         if (rule) {
2576                 context_destroy(&rule->au_ctxt);
2577                 kfree(rule);
2578         }
2579 }
2580
2581 int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule)
2582 {
2583         struct selinux_audit_rule *tmprule;
2584         struct role_datum *roledatum;
2585         struct type_datum *typedatum;
2586         struct user_datum *userdatum;
2587         struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule;
2588         int rc = 0;
2589
2590         *rule = NULL;
2591
2592         if (!ss_initialized)
2593                 return -EOPNOTSUPP;
2594
2595         switch (field) {
2596         case AUDIT_SUBJ_USER:
2597         case AUDIT_SUBJ_ROLE:
2598         case AUDIT_SUBJ_TYPE:
2599         case AUDIT_OBJ_USER:
2600         case AUDIT_OBJ_ROLE:
2601         case AUDIT_OBJ_TYPE:
2602                 /* only 'equals' and 'not equals' fit user, role, and type */
2603                 if (op != Audit_equal && op != Audit_not_equal)
2604                         return -EINVAL;
2605                 break;
2606         case AUDIT_SUBJ_SEN:
2607         case AUDIT_SUBJ_CLR:
2608         case AUDIT_OBJ_LEV_LOW:
2609         case AUDIT_OBJ_LEV_HIGH:
2610                 /* we do not allow a range, indicated by the presense of '-' */
2611                 if (strchr(rulestr, '-'))
2612                         return -EINVAL;
2613                 break;
2614         default:
2615                 /* only the above fields are valid */
2616                 return -EINVAL;
2617         }
2618
2619         tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL);
2620         if (!tmprule)
2621                 return -ENOMEM;
2622
2623         context_init(&tmprule->au_ctxt);
2624
2625         read_lock(&policy_rwlock);
2626
2627         tmprule->au_seqno = latest_granting;
2628
2629         switch (field) {
2630         case AUDIT_SUBJ_USER:
2631         case AUDIT_OBJ_USER:
2632                 userdatum = hashtab_search(policydb.p_users.table, rulestr);
2633                 if (!userdatum)
2634                         rc = -EINVAL;
2635                 else
2636                         tmprule->au_ctxt.user = userdatum->value;
2637                 break;
2638         case AUDIT_SUBJ_ROLE:
2639         case AUDIT_OBJ_ROLE:
2640                 roledatum = hashtab_search(policydb.p_roles.table, rulestr);
2641                 if (!roledatum)
2642                         rc = -EINVAL;
2643                 else
2644                         tmprule->au_ctxt.role = roledatum->value;
2645                 break;
2646         case AUDIT_SUBJ_TYPE:
2647         case AUDIT_OBJ_TYPE:
2648                 typedatum = hashtab_search(policydb.p_types.table, rulestr);
2649                 if (!typedatum)
2650                         rc = -EINVAL;
2651                 else
2652                         tmprule->au_ctxt.type = typedatum->value;
2653                 break;
2654         case AUDIT_SUBJ_SEN:
2655         case AUDIT_SUBJ_CLR:
2656         case AUDIT_OBJ_LEV_LOW:
2657         case AUDIT_OBJ_LEV_HIGH:
2658                 rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC);
2659                 break;
2660         }
2661
2662         read_unlock(&policy_rwlock);
2663
2664         if (rc) {
2665                 selinux_audit_rule_free(tmprule);
2666                 tmprule = NULL;
2667         }
2668
2669         *rule = tmprule;
2670
2671         return rc;
2672 }
2673
2674 /* Check to see if the rule contains any selinux fields */
2675 int selinux_audit_rule_known(struct audit_krule *rule)
2676 {
2677         int i;
2678
2679         for (i = 0; i < rule->field_count; i++) {
2680                 struct audit_field *f = &rule->fields[i];
2681                 switch (f->type) {
2682                 case AUDIT_SUBJ_USER:
2683                 case AUDIT_SUBJ_ROLE:
2684                 case AUDIT_SUBJ_TYPE:
2685                 case AUDIT_SUBJ_SEN:
2686                 case AUDIT_SUBJ_CLR:
2687                 case AUDIT_OBJ_USER:
2688                 case AUDIT_OBJ_ROLE:
2689                 case AUDIT_OBJ_TYPE:
2690                 case AUDIT_OBJ_LEV_LOW:
2691                 case AUDIT_OBJ_LEV_HIGH:
2692                         return 1;
2693                 }
2694         }
2695
2696         return 0;
2697 }
2698
2699 int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule,
2700                              struct audit_context *actx)
2701 {
2702         struct context *ctxt;
2703         struct mls_level *level;
2704         struct selinux_audit_rule *rule = vrule;
2705         int match = 0;
2706
2707         if (!rule) {
2708                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2709                           "selinux_audit_rule_match: missing rule\n");
2710                 return -ENOENT;
2711         }
2712
2713         read_lock(&policy_rwlock);
2714
2715         if (rule->au_seqno < latest_granting) {
2716                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2717                           "selinux_audit_rule_match: stale rule\n");
2718                 match = -ESTALE;
2719                 goto out;
2720         }
2721
2722         ctxt = sidtab_search(&sidtab, sid);
2723         if (!ctxt) {
2724                 audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR,
2725                           "selinux_audit_rule_match: unrecognized SID %d\n",
2726                           sid);
2727                 match = -ENOENT;
2728                 goto out;
2729         }
2730
2731         /* a field/op pair that is not caught here will simply fall through
2732            without a match */
2733         switch (field) {
2734         case AUDIT_SUBJ_USER:
2735         case AUDIT_OBJ_USER:
2736                 switch (op) {
2737                 case Audit_equal:
2738                         match = (ctxt->user == rule->au_ctxt.user);
2739                         break;
2740                 case Audit_not_equal:
2741                         match = (ctxt->user != rule->au_ctxt.user);
2742                         break;
2743                 }
2744                 break;
2745         case AUDIT_SUBJ_ROLE:
2746         case AUDIT_OBJ_ROLE:
2747                 switch (op) {
2748                 case Audit_equal:
2749                         match = (ctxt->role == rule->au_ctxt.role);
2750                         break;
2751                 case Audit_not_equal:
2752                         match = (ctxt->role != rule->au_ctxt.role);
2753                         break;
2754                 }
2755                 break;
2756         case AUDIT_SUBJ_TYPE:
2757         case AUDIT_OBJ_TYPE:
2758                 switch (op) {
2759                 case Audit_equal:
2760                         match = (ctxt->type == rule->au_ctxt.type);
2761                         break;
2762                 case Audit_not_equal:
2763                         match = (ctxt->type != rule->au_ctxt.type);
2764                         break;
2765                 }
2766                 break;
2767         case AUDIT_SUBJ_SEN:
2768         case AUDIT_SUBJ_CLR:
2769         case AUDIT_OBJ_LEV_LOW:
2770         case AUDIT_OBJ_LEV_HIGH:
2771                 level = ((field == AUDIT_SUBJ_SEN ||
2772                           field == AUDIT_OBJ_LEV_LOW) ?
2773                          &ctxt->range.level[0] : &ctxt->range.level[1]);
2774                 switch (op) {
2775                 case Audit_equal:
2776                         match = mls_level_eq(&rule->au_ctxt.range.level[0],
2777                                              level);
2778                         break;
2779                 case Audit_not_equal:
2780                         match = !mls_level_eq(&rule->au_ctxt.range.level[0],
2781                                               level);
2782                         break;
2783                 case Audit_lt:
2784                         match = (mls_level_dom(&rule->au_ctxt.range.level[0],
2785                                                level) &&
2786                                  !mls_level_eq(&rule->au_ctxt.range.level[0],
2787                                                level));
2788                         break;
2789                 case Audit_le:
2790                         match = mls_level_dom(&rule->au_ctxt.range.level[0],
2791                                               level);
2792                         break;
2793                 case Audit_gt:
2794                         match = (mls_level_dom(level,
2795                                               &rule->au_ctxt.range.level[0]) &&
2796                                  !mls_level_eq(level,
2797                                                &rule->au_ctxt.range.level[0]));
2798                         break;
2799                 case Audit_ge:
2800                         match = mls_level_dom(level,
2801                                               &rule->au_ctxt.range.level[0]);
2802                         break;
2803                 }
2804         }
2805
2806 out:
2807         read_unlock(&policy_rwlock);
2808         return match;
2809 }
2810
2811 static int (*aurule_callback)(void) = audit_update_lsm_rules;
2812
2813 static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid,
2814                                u16 class, u32 perms, u32 *retained)
2815 {
2816         int err = 0;
2817
2818         if (event == AVC_CALLBACK_RESET && aurule_callback)
2819                 err = aurule_callback();
2820         return err;
2821 }
2822
2823 static int __init aurule_init(void)
2824 {
2825         int err;
2826
2827         err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET,
2828                                SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0);
2829         if (err)
2830                 panic("avc_add_callback() failed, error %d\n", err);
2831
2832         return err;
2833 }
2834 __initcall(aurule_init);
2835
2836 #ifdef CONFIG_NETLABEL
2837 /**
2838  * security_netlbl_cache_add - Add an entry to the NetLabel cache
2839  * @secattr: the NetLabel packet security attributes
2840  * @sid: the SELinux SID
2841  *
2842  * Description:
2843  * Attempt to cache the context in @ctx, which was derived from the packet in
2844  * @skb, in the NetLabel subsystem cache.  This function assumes @secattr has
2845  * already been initialized.
2846  *
2847  */
2848 static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr,
2849                                       u32 sid)
2850 {
2851         u32 *sid_cache;
2852
2853         sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC);
2854         if (sid_cache == NULL)
2855                 return;
2856         secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC);
2857         if (secattr->cache == NULL) {
2858                 kfree(sid_cache);
2859                 return;
2860         }
2861
2862         *sid_cache = sid;
2863         secattr->cache->free = kfree;
2864         secattr->cache->data = sid_cache;
2865         secattr->flags |= NETLBL_SECATTR_CACHE;
2866 }
2867
2868 /**
2869  * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID
2870  * @secattr: the NetLabel packet security attributes
2871  * @sid: the SELinux SID
2872  *
2873  * Description:
2874  * Convert the given NetLabel security attributes in @secattr into a
2875  * SELinux SID.  If the @secattr field does not contain a full SELinux
2876  * SID/context then use SECINITSID_NETMSG as the foundation.  If possibile the
2877  * 'cache' field of @secattr is set and the CACHE flag is set; this is to
2878  * allow the @secattr to be used by NetLabel to cache the secattr to SID
2879  * conversion for future lookups.  Returns zero on success, negative values on
2880  * failure.
2881  *
2882  */
2883 int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr,
2884                                    u32 *sid)
2885 {
2886         int rc = -EIDRM;
2887         struct context *ctx;
2888         struct context ctx_new;
2889
2890         if (!ss_initialized) {
2891                 *sid = SECSID_NULL;
2892                 return 0;
2893         }
2894
2895         read_lock(&policy_rwlock);
2896
2897         if (secattr->flags & NETLBL_SECATTR_CACHE) {
2898                 *sid = *(u32 *)secattr->cache->data;
2899                 rc = 0;
2900         } else if (secattr->flags & NETLBL_SECATTR_SECID) {
2901                 *sid = secattr->attr.secid;
2902                 rc = 0;
2903         } else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) {
2904                 ctx = sidtab_search(&sidtab, SECINITSID_NETMSG);
2905                 if (ctx == NULL)
2906                         goto netlbl_secattr_to_sid_return;
2907
2908                 context_init(&ctx_new);
2909                 ctx_new.user = ctx->user;
2910                 ctx_new.role = ctx->role;
2911                 ctx_new.type = ctx->type;
2912                 mls_import_netlbl_lvl(&ctx_new, secattr);
2913                 if (secattr->flags & NETLBL_SECATTR_MLS_CAT) {
2914                         if (ebitmap_netlbl_import(&ctx_new.range.level[0].cat,
2915                                                   secattr->attr.mls.cat) != 0)
2916                                 goto netlbl_secattr_to_sid_return;
2917                         memcpy(&ctx_new.range.level[1].cat,
2918                                &ctx_new.range.level[0].cat,
2919                                sizeof(ctx_new.range.level[0].cat));
2920                 }
2921                 if (mls_context_isvalid(&policydb, &ctx_new) != 1)
2922                         goto netlbl_secattr_to_sid_return_cleanup;
2923
2924                 rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid);
2925                 if (rc != 0)
2926                         goto netlbl_secattr_to_sid_return_cleanup;
2927
2928                 security_netlbl_cache_add(secattr, *sid);
2929
2930                 ebitmap_destroy(&ctx_new.range.level[0].cat);
2931         } else {
2932                 *sid = SECSID_NULL;
2933                 rc = 0;
2934         }
2935
2936 netlbl_secattr_to_sid_return:
2937         read_unlock(&policy_rwlock);
2938         return rc;
2939 netlbl_secattr_to_sid_return_cleanup:
2940         ebitmap_destroy(&ctx_new.range.level[0].cat);
2941         goto netlbl_secattr_to_sid_return;
2942 }
2943
2944 /**
2945  * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr
2946  * @sid: the SELinux SID
2947  * @secattr: the NetLabel packet security attributes
2948  *
2949  * Description:
2950  * Convert the given SELinux SID in @sid into a NetLabel security attribute.
2951  * Returns zero on success, negative values on failure.
2952  *
2953  */
2954 int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr)
2955 {
2956         int rc;
2957         struct context *ctx;
2958
2959         if (!ss_initialized)
2960                 return 0;
2961
2962         read_lock(&policy_rwlock);
2963         ctx = sidtab_search(&sidtab, sid);
2964         if (ctx == NULL) {
2965                 rc = -ENOENT;
2966                 goto netlbl_sid_to_secattr_failure;
2967         }
2968         secattr->domain = kstrdup(policydb.p_type_val_to_name[ctx->type - 1],
2969                                   GFP_ATOMIC);
2970         if (secattr->domain == NULL) {
2971                 rc = -ENOMEM;
2972                 goto netlbl_sid_to_secattr_failure;
2973         }
2974         secattr->attr.secid = sid;
2975         secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID;
2976         mls_export_netlbl_lvl(ctx, secattr);
2977         rc = mls_export_netlbl_cat(ctx, secattr);
2978         if (rc != 0)
2979                 goto netlbl_sid_to_secattr_failure;
2980         read_unlock(&policy_rwlock);
2981
2982         return 0;
2983
2984 netlbl_sid_to_secattr_failure:
2985         read_unlock(&policy_rwlock);
2986         return rc;
2987 }
2988 #endif /* CONFIG_NETLABEL */