security/selinux/ss/services.c

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