security/apparmor/policy_unpack.c

   1 /*
   2  * AppArmor security module
   3  *
   4  * This file contains AppArmor functions for unpacking policy loaded from
   5  * userspace.
   6  *
   7  * Copyright (C) 1998-2008 Novell/SUSE
   8  * Copyright 2009-2010 Canonical Ltd.
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License as
  12  * published by the Free Software Foundation, version 2 of the
  13  * License.
  14  *
  15  * AppArmor uses a serialized binary format for loading policy. To find
  16  * policy format documentation look in Documentation/security/apparmor.txt
  17  * All policy is validated before it is used.
  18  */
  19
  20 #include <asm/unaligned.h>
  21 #include <linux/ctype.h>
  22 #include <linux/errno.h>
  23
  24 #include "include/apparmor.h"
  25 #include "include/audit.h"
  26 #include "include/context.h"
  27 #include "include/crypto.h"
  28 #include "include/match.h"
  29 #include "include/policy.h"
  30 #include "include/policy_unpack.h"
  31
  32 #define K_ABI_MASK 0x3ff
  33 #define FORCE_COMPLAIN_FLAG 0x800
  34 #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
  35 #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
  36
  37 #define v5      5       /* base version */
  38 #define v6      6       /* per entry policydb mediation check */
  39 #define v7      7       /* full network masking */
  40
  41 /*
  42  * The AppArmor interface treats data as a type byte followed by the
  43  * actual data.  The interface has the notion of a a named entry
  44  * which has a name (AA_NAME typecode followed by name string) followed by
  45  * the entries typecode and data.  Named types allow for optional
  46  * elements and extensions to be added and tested for without breaking
  47  * backwards compatibility.
  48  */
  49
  50 enum aa_code {
  51         AA_U8,
  52         AA_U16,
  53         AA_U32,
  54         AA_U64,
  55         AA_NAME,                /* same as string except it is items name */
  56         AA_STRING,
  57         AA_BLOB,
  58         AA_STRUCT,
  59         AA_STRUCTEND,
  60         AA_LIST,
  61         AA_LISTEND,
  62         AA_ARRAY,
  63         AA_ARRAYEND,
  64 };
  65
  66 /*
  67  * aa_ext is the read of the buffer containing the serialized profile.  The
  68  * data is copied into a kernel buffer in apparmorfs and then handed off to
  69  * the unpack routines.
  70  */
  71 struct aa_ext {
  72         void *start;
  73         void *end;
  74         void *pos;              /* pointer to current position in the buffer */
  75         u32 version;
  76 };
  77
  78 /* audit callback for unpack fields */
  79 static void audit_cb(struct audit_buffer *ab, void *va)
  80 {
  81         struct common_audit_data *sa = va;
  82
  83         if (aad(sa)->iface.ns) {
  84                 audit_log_format(ab, " ns=");
  85                 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
  86         }
  87         if (aad(sa)->iface.name) {
  88                 audit_log_format(ab, " name=");
  89                 audit_log_untrustedstring(ab, aad(sa)->iface.name);
  90         }
  91         if (aad(sa)->iface.pos)
  92                 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
  93 }
  94
  95 /**
  96  * audit_iface - do audit message for policy unpacking/load/replace/remove
  97  * @new: profile if it has been allocated (MAYBE NULL)
  98  * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
  99  * @name: name of the profile being manipulated (MAYBE NULL)
 100  * @info: any extra info about the failure (MAYBE NULL)
 101  * @e: buffer position info
 102  * @error: error code
 103  *
 104  * Returns: %0 or error
 105  */
 106 static int audit_iface(struct aa_profile *new, const char *ns_name,
 107                        const char *name, const char *info, struct aa_ext *e,
 108                        int error)
 109 {
 110         struct aa_profile *profile = __aa_current_profile();
 111         DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
 112         if (e)
 113                 aad(&sa)->iface.pos = e->pos - e->start;
 114         aad(&sa)->iface.ns = ns_name;
 115         if (new)
 116                 aad(&sa)->iface.name = new->base.hname;
 117         else
 118                 aad(&sa)->iface.name = name;
 119         aad(&sa)->info = info;
 120         aad(&sa)->error = error;
 121
 122         return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
 123 }
 124
 125 void aa_loaddata_kref(struct kref *kref)
 126 {
 127         struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
 128
 129         if (d) {
 130                 kzfree(d->hash);
 131                 kvfree(d);
 132         }
 133 }
 134
 135 /* test if read will be in packed data bounds */
 136 static bool inbounds(struct aa_ext *e, size_t size)
 137 {
 138         return (size <= e->end - e->pos);
 139 }
 140
 141 /**
 142  * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
 143  * @e: serialized data read head (NOT NULL)
 144  * @chunk: start address for chunk of data (NOT NULL)
 145  *
 146  * Returns: the size of chunk found with the read head at the end of the chunk.
 147  */
 148 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
 149 {
 150         size_t size = 0;
 151
 152         if (!inbounds(e, sizeof(u16)))
 153                 return 0;
 154         size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
 155         e->pos += sizeof(__le16);
 156         if (!inbounds(e, size))
 157                 return 0;
 158         *chunk = e->pos;
 159         e->pos += size;
 160         return size;
 161 }
 162
 163 /* unpack control byte */
 164 static bool unpack_X(struct aa_ext *e, enum aa_code code)
 165 {
 166         if (!inbounds(e, 1))
 167                 return 0;
 168         if (*(u8 *) e->pos != code)
 169                 return 0;
 170         e->pos++;
 171         return 1;
 172 }
 173
 174 /**
 175  * unpack_nameX - check is the next element is of type X with a name of @name
 176  * @e: serialized data extent information  (NOT NULL)
 177  * @code: type code
 178  * @name: name to match to the serialized element.  (MAYBE NULL)
 179  *
 180  * check that the next serialized data element is of type X and has a tag
 181  * name @name.  If @name is specified then there must be a matching
 182  * name element in the stream.  If @name is NULL any name element will be
 183  * skipped and only the typecode will be tested.
 184  *
 185  * Returns 1 on success (both type code and name tests match) and the read
 186  * head is advanced past the headers
 187  *
 188  * Returns: 0 if either match fails, the read head does not move
 189  */
 190 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
 191 {
 192         /*
 193          * May need to reset pos if name or type doesn't match
 194          */
 195         void *pos = e->pos;
 196         /*
 197          * Check for presence of a tagname, and if present name size
 198          * AA_NAME tag value is a u16.
 199          */
 200         if (unpack_X(e, AA_NAME)) {
 201                 char *tag = NULL;
 202                 size_t size = unpack_u16_chunk(e, &tag);
 203                 /* if a name is specified it must match. otherwise skip tag */
 204                 if (name && (!size || strcmp(name, tag)))
 205                         goto fail;
 206         } else if (name) {
 207                 /* if a name is specified and there is no name tag fail */
 208                 goto fail;
 209         }
 210
 211         /* now check if type code matches */
 212         if (unpack_X(e, code))
 213                 return 1;
 214
 215 fail:
 216         e->pos = pos;
 217         return 0;
 218 }
 219
 220 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
 221 {
 222         if (unpack_nameX(e, AA_U32, name)) {
 223                 if (!inbounds(e, sizeof(u32)))
 224                         return 0;
 225                 if (data)
 226                         *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 227                 e->pos += sizeof(u32);
 228                 return 1;
 229         }
 230         return 0;
 231 }
 232
 233 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
 234 {
 235         if (unpack_nameX(e, AA_U64, name)) {
 236                 if (!inbounds(e, sizeof(u64)))
 237                         return 0;
 238                 if (data)
 239                         *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
 240                 e->pos += sizeof(u64);
 241                 return 1;
 242         }
 243         return 0;
 244 }
 245
 246 static size_t unpack_array(struct aa_ext *e, const char *name)
 247 {
 248         if (unpack_nameX(e, AA_ARRAY, name)) {
 249                 int size;
 250                 if (!inbounds(e, sizeof(u16)))
 251                         return 0;
 252                 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
 253                 e->pos += sizeof(u16);
 254                 return size;
 255         }
 256         return 0;
 257 }
 258
 259 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
 260 {
 261         if (unpack_nameX(e, AA_BLOB, name)) {
 262                 u32 size;
 263                 if (!inbounds(e, sizeof(u32)))
 264                         return 0;
 265                 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 266                 e->pos += sizeof(u32);
 267                 if (inbounds(e, (size_t) size)) {
 268                         *blob = e->pos;
 269                         e->pos += size;
 270                         return size;
 271                 }
 272         }
 273         return 0;
 274 }
 275
 276 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
 277 {
 278         char *src_str;
 279         size_t size = 0;
 280         void *pos = e->pos;
 281         *string = NULL;
 282         if (unpack_nameX(e, AA_STRING, name)) {
 283                 size = unpack_u16_chunk(e, &src_str);
 284                 if (size) {
 285                         /* strings are null terminated, length is size - 1 */
 286                         if (src_str[size - 1] != 0)
 287                                 goto fail;
 288                         *string = src_str;
 289                 }
 290         }
 291         return size;
 292
 293 fail:
 294         e->pos = pos;
 295         return 0;
 296 }
 297
 298 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
 299 {
 300         const char *tmp;
 301         void *pos = e->pos;
 302         int res = unpack_str(e, &tmp, name);
 303         *string = NULL;
 304
 305         if (!res)
 306                 return 0;
 307
 308         *string = kmemdup(tmp, res, GFP_KERNEL);
 309         if (!*string) {
 310                 e->pos = pos;
 311                 return 0;
 312         }
 313
 314         return res;
 315 }
 316
 317 #define DFA_VALID_PERM_MASK             0xffffffff
 318 #define DFA_VALID_PERM2_MASK            0xffffffff
 319
 320 /**
 321  * verify_accept - verify the accept tables of a dfa
 322  * @dfa: dfa to verify accept tables of (NOT NULL)
 323  * @flags: flags governing dfa
 324  *
 325  * Returns: 1 if valid accept tables else 0 if error
 326  */
 327 static bool verify_accept(struct aa_dfa *dfa, int flags)
 328 {
 329         int i;
 330
 331         /* verify accept permissions */
 332         for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
 333                 int mode = ACCEPT_TABLE(dfa)[i];
 334
 335                 if (mode & ~DFA_VALID_PERM_MASK)
 336                         return 0;
 337
 338                 if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
 339                         return 0;
 340         }
 341         return 1;
 342 }
 343
 344 /**
 345  * unpack_dfa - unpack a file rule dfa
 346  * @e: serialized data extent information (NOT NULL)
 347  *
 348  * returns dfa or ERR_PTR or NULL if no dfa
 349  */
 350 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
 351 {
 352         char *blob = NULL;
 353         size_t size;
 354         struct aa_dfa *dfa = NULL;
 355
 356         size = unpack_blob(e, &blob, "aadfa");
 357         if (size) {
 358                 /*
 359                  * The dfa is aligned with in the blob to 8 bytes
 360                  * from the beginning of the stream.
 361                  * alignment adjust needed by dfa unpack
 362                  */
 363                 size_t sz = blob - (char *) e->start -
 364                         ((e->pos - e->start) & 7);
 365                 size_t pad = ALIGN(sz, 8) - sz;
 366                 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
 367                         TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
 368                 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
 369
 370                 if (IS_ERR(dfa))
 371                         return dfa;
 372
 373                 if (!verify_accept(dfa, flags))
 374                         goto fail;
 375         }
 376
 377         return dfa;
 378
 379 fail:
 380         aa_put_dfa(dfa);
 381         return ERR_PTR(-EPROTO);
 382 }
 383
 384 /**
 385  * unpack_trans_table - unpack a profile transition table
 386  * @e: serialized data extent information  (NOT NULL)
 387  * @profile: profile to add the accept table to (NOT NULL)
 388  *
 389  * Returns: 1 if table successfully unpacked
 390  */
 391 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
 392 {
 393         void *pos = e->pos;
 394
 395         /* exec table is optional */
 396         if (unpack_nameX(e, AA_STRUCT, "xtable")) {
 397                 int i, size;
 398
 399                 size = unpack_array(e, NULL);
 400                 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
 401                 if (size > 16 - 4)
 402                         goto fail;
 403                 profile->file.trans.table = kzalloc(sizeof(char *) * size,
 404                                                     GFP_KERNEL);
 405                 if (!profile->file.trans.table)
 406                         goto fail;
 407
 408                 profile->file.trans.size = size;
 409                 for (i = 0; i < size; i++) {
 410                         char *str;
 411                         int c, j, size2 = unpack_strdup(e, &str, NULL);
 412                         /* unpack_strdup verifies that the last character is
 413                          * null termination byte.
 414                          */
 415                         if (!size2)
 416                                 goto fail;
 417                         profile->file.trans.table[i] = str;
 418                         /* verify that name doesn't start with space */
 419                         if (isspace(*str))
 420                                 goto fail;
 421
 422                         /* count internal #  of internal \0 */
 423                         for (c = j = 0; j < size2 - 2; j++) {
 424                                 if (!str[j])
 425                                         c++;
 426                         }
 427                         if (*str == ':') {
 428                                 /* beginning with : requires an embedded \0,
 429                                  * verify that exactly 1 internal \0 exists
 430                                  * trailing \0 already verified by unpack_strdup
 431                                  */
 432                                 if (c != 1)
 433                                         goto fail;
 434                                 /* first character after : must be valid */
 435                                 if (!str[1])
 436                                         goto fail;
 437                         } else if (c)
 438                                 /* fail - all other cases with embedded \0 */
 439                                 goto fail;
 440                 }
 441                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 442                         goto fail;
 443                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 444                         goto fail;
 445         }
 446         return 1;
 447
 448 fail:
 449         aa_free_domain_entries(&profile->file.trans);
 450         e->pos = pos;
 451         return 0;
 452 }
 453
 454 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
 455 {
 456         void *pos = e->pos;
 457
 458         /* rlimits are optional */
 459         if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
 460                 int i, size;
 461                 u32 tmp = 0;
 462                 if (!unpack_u32(e, &tmp, NULL))
 463                         goto fail;
 464                 profile->rlimits.mask = tmp;
 465
 466                 size = unpack_array(e, NULL);
 467                 if (size > RLIM_NLIMITS)
 468                         goto fail;
 469                 for (i = 0; i < size; i++) {
 470                         u64 tmp2 = 0;
 471                         int a = aa_map_resource(i);
 472                         if (!unpack_u64(e, &tmp2, NULL))
 473                                 goto fail;
 474                         profile->rlimits.limits[a].rlim_max = tmp2;
 475                 }
 476                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 477                         goto fail;
 478                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 479                         goto fail;
 480         }
 481         return 1;
 482
 483 fail:
 484         e->pos = pos;
 485         return 0;
 486 }
 487
 488 static void *kvmemdup(const void *src, size_t len)
 489 {
 490         void *p = kvmalloc(len);
 491
 492         if (p)
 493                 memcpy(p, src, len);
 494         return p;
 495 }
 496
 497 static u32 strhash(const void *data, u32 len, u32 seed)
 498 {
 499         const char * const *key = data;
 500
 501         return jhash(*key, strlen(*key), seed);
 502 }
 503
 504 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
 505 {
 506         const struct aa_data *data = obj;
 507         const char * const *key = arg->key;
 508
 509         return strcmp(data->key, *key);
 510 }
 511
 512 /**
 513  * unpack_profile - unpack a serialized profile
 514  * @e: serialized data extent information (NOT NULL)
 515  *
 516  * NOTE: unpack profile sets audit struct if there is a failure
 517  */
 518 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 519 {
 520         struct aa_profile *profile = NULL;
 521         const char *tmpname, *tmpns = NULL, *name = NULL;
 522         size_t ns_len;
 523         struct rhashtable_params params = { 0 };
 524         char *key = NULL;
 525         struct aa_data *data;
 526         int i, error = -EPROTO;
 527         kernel_cap_t tmpcap;
 528         u32 tmp;
 529
 530         *ns_name = NULL;
 531
 532         /* check that we have the right struct being passed */
 533         if (!unpack_nameX(e, AA_STRUCT, "profile"))
 534                 goto fail;
 535         if (!unpack_str(e, &name, NULL))
 536                 goto fail;
 537         if (*name == '\0')
 538                 goto fail;
 539
 540         tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
 541         if (tmpns) {
 542                 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
 543                 if (!*ns_name)
 544                         goto fail;
 545                 name = tmpname;
 546         }
 547
 548         profile = aa_alloc_profile(name, GFP_KERNEL);
 549         if (!profile)
 550                 return ERR_PTR(-ENOMEM);
 551
 552         /* profile renaming is optional */
 553         (void) unpack_str(e, &profile->rename, "rename");
 554
 555         /* attachment string is optional */
 556         (void) unpack_str(e, &profile->attach, "attach");
 557
 558         /* xmatch is optional and may be NULL */
 559         profile->xmatch = unpack_dfa(e);
 560         if (IS_ERR(profile->xmatch)) {
 561                 error = PTR_ERR(profile->xmatch);
 562                 profile->xmatch = NULL;
 563                 goto fail;
 564         }
 565         /* xmatch_len is not optional if xmatch is set */
 566         if (profile->xmatch) {
 567                 if (!unpack_u32(e, &tmp, NULL))
 568                         goto fail;
 569                 profile->xmatch_len = tmp;
 570         }
 571
 572         /* per profile debug flags (complain, audit) */
 573         if (!unpack_nameX(e, AA_STRUCT, "flags"))
 574                 goto fail;
 575         if (!unpack_u32(e, &tmp, NULL))
 576                 goto fail;
 577         if (tmp & PACKED_FLAG_HAT)
 578                 profile->flags |= PFLAG_HAT;
 579         if (!unpack_u32(e, &tmp, NULL))
 580                 goto fail;
 581         if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
 582                 profile->mode = APPARMOR_COMPLAIN;
 583         else if (tmp == PACKED_MODE_KILL)
 584                 profile->mode = APPARMOR_KILL;
 585         else if (tmp == PACKED_MODE_UNCONFINED)
 586                 profile->mode = APPARMOR_UNCONFINED;
 587         if (!unpack_u32(e, &tmp, NULL))
 588                 goto fail;
 589         if (tmp)
 590                 profile->audit = AUDIT_ALL;
 591
 592         if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 593                 goto fail;
 594
 595         /* path_flags is optional */
 596         if (unpack_u32(e, &profile->path_flags, "path_flags"))
 597                 profile->path_flags |= profile->flags & PFLAG_MEDIATE_DELETED;
 598         else
 599                 /* set a default value if path_flags field is not present */
 600                 profile->path_flags = PFLAG_MEDIATE_DELETED;
 601
 602         if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
 603                 goto fail;
 604         if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
 605                 goto fail;
 606         if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
 607                 goto fail;
 608         if (!unpack_u32(e, &tmpcap.cap[0], NULL))
 609                 goto fail;
 610
 611         if (unpack_nameX(e, AA_STRUCT, "caps64")) {
 612                 /* optional upper half of 64 bit caps */
 613                 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
 614                         goto fail;
 615                 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
 616                         goto fail;
 617                 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
 618                         goto fail;
 619                 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
 620                         goto fail;
 621                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 622                         goto fail;
 623         }
 624
 625         if (unpack_nameX(e, AA_STRUCT, "capsx")) {
 626                 /* optional extended caps mediation mask */
 627                 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
 628                         goto fail;
 629                 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
 630                         goto fail;
 631                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 632                         goto fail;
 633         }
 634
 635         if (!unpack_rlimits(e, profile))
 636                 goto fail;
 637
 638         if (unpack_nameX(e, AA_STRUCT, "policydb")) {
 639                 /* generic policy dfa - optional and may be NULL */
 640                 profile->policy.dfa = unpack_dfa(e);
 641                 if (IS_ERR(profile->policy.dfa)) {
 642                         error = PTR_ERR(profile->policy.dfa);
 643                         profile->policy.dfa = NULL;
 644                         goto fail;
 645                 } else if (!profile->policy.dfa) {
 646                         error = -EPROTO;
 647                         goto fail;
 648                 }
 649                 if (!unpack_u32(e, &profile->policy.start[0], "start"))
 650                         /* default start state */
 651                         profile->policy.start[0] = DFA_START;
 652                 /* setup class index */
 653                 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
 654                         profile->policy.start[i] =
 655                                 aa_dfa_next(profile->policy.dfa,
 656                                             profile->policy.start[0],
 657                                             i);
 658                 }
 659                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 660                         goto fail;
 661         } else
 662                 profile->policy.dfa = aa_get_dfa(nulldfa);
 663
 664         /* get file rules */
 665         profile->file.dfa = unpack_dfa(e);
 666         if (IS_ERR(profile->file.dfa)) {
 667                 error = PTR_ERR(profile->file.dfa);
 668                 profile->file.dfa = NULL;
 669                 goto fail;
 670         } else if (profile->file.dfa) {
 671                 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
 672                         /* default start state */
 673                         profile->file.start = DFA_START;
 674         } else if (profile->policy.dfa &&
 675                    profile->policy.start[AA_CLASS_FILE]) {
 676                 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
 677                 profile->file.start = profile->policy.start[AA_CLASS_FILE];
 678         } else
 679                 profile->file.dfa = aa_get_dfa(nulldfa);
 680
 681         if (!unpack_trans_table(e, profile))
 682                 goto fail;
 683
 684         if (unpack_nameX(e, AA_STRUCT, "data")) {
 685                 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
 686                 if (!profile->data)
 687                         goto fail;
 688
 689                 params.nelem_hint = 3;
 690                 params.key_len = sizeof(void *);
 691                 params.key_offset = offsetof(struct aa_data, key);
 692                 params.head_offset = offsetof(struct aa_data, head);
 693                 params.hashfn = strhash;
 694                 params.obj_cmpfn = datacmp;
 695
 696                 if (rhashtable_init(profile->data, &params))
 697                         goto fail;
 698
 699                 while (unpack_strdup(e, &key, NULL)) {
 700                         data = kzalloc(sizeof(*data), GFP_KERNEL);
 701                         if (!data) {
 702                                 kzfree(key);
 703                                 goto fail;
 704                         }
 705
 706                         data->key = key;
 707                         data->size = unpack_blob(e, &data->data, NULL);
 708                         data->data = kvmemdup(data->data, data->size);
 709                         if (data->size && !data->data) {
 710                                 kzfree(data->key);
 711                                 kzfree(data);
 712                                 goto fail;
 713                         }
 714
 715                         rhashtable_insert_fast(profile->data, &data->head,
 716                                                profile->data->p);
 717                 }
 718
 719                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 720                         goto fail;
 721         }
 722
 723         if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 724                 goto fail;
 725
 726         return profile;
 727
 728 fail:
 729         if (profile)
 730                 name = NULL;
 731         else if (!name)
 732                 name = "unknown";
 733         audit_iface(profile, NULL, name, "failed to unpack profile", e,
 734                     error);
 735         aa_free_profile(profile);
 736
 737         return ERR_PTR(error);
 738 }
 739
 740 /**
 741  * verify_head - unpack serialized stream header
 742  * @e: serialized data read head (NOT NULL)
 743  * @required: whether the header is required or optional
 744  * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
 745  *
 746  * Returns: error or 0 if header is good
 747  */
 748 static int verify_header(struct aa_ext *e, int required, const char **ns)
 749 {
 750         int error = -EPROTONOSUPPORT;
 751         const char *name = NULL;
 752         *ns = NULL;
 753
 754         /* get the interface version */
 755         if (!unpack_u32(e, &e->version, "version")) {
 756                 if (required) {
 757                         audit_iface(NULL, NULL, NULL, "invalid profile format",
 758                                     e, error);
 759                         return error;
 760                 }
 761         }
 762
 763         /* Check that the interface version is currently supported.
 764          * if not specified use previous version
 765          * Mask off everything that is not kernel abi version
 766          */
 767         if (VERSION_LT(e->version, v5) && VERSION_GT(e->version, v7)) {
 768                 audit_iface(NULL, NULL, NULL, "unsupported interface version",
 769                             e, error);
 770                 return error;
 771         }
 772
 773         /* read the namespace if present */
 774         if (unpack_str(e, &name, "namespace")) {
 775                 if (*name == '\0') {
 776                         audit_iface(NULL, NULL, NULL, "invalid namespace name",
 777                                     e, error);
 778                         return error;
 779                 }
 780                 if (*ns && strcmp(*ns, name))
 781                         audit_iface(NULL, NULL, NULL, "invalid ns change", e,
 782                                     error);
 783                 else if (!*ns)
 784                         *ns = name;
 785         }
 786
 787         return 0;
 788 }
 789
 790 static bool verify_xindex(int xindex, int table_size)
 791 {
 792         int index, xtype;
 793         xtype = xindex & AA_X_TYPE_MASK;
 794         index = xindex & AA_X_INDEX_MASK;
 795         if (xtype == AA_X_TABLE && index >= table_size)
 796                 return 0;
 797         return 1;
 798 }
 799
 800 /* verify dfa xindexes are in range of transition tables */
 801 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
 802 {
 803         int i;
 804         for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
 805                 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
 806                         return 0;
 807                 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
 808                         return 0;
 809         }
 810         return 1;
 811 }
 812
 813 /**
 814  * verify_profile - Do post unpack analysis to verify profile consistency
 815  * @profile: profile to verify (NOT NULL)
 816  *
 817  * Returns: 0 if passes verification else error
 818  */
 819 static int verify_profile(struct aa_profile *profile)
 820 {
 821         if (profile->file.dfa &&
 822             !verify_dfa_xindex(profile->file.dfa,
 823                                profile->file.trans.size)) {
 824                 audit_iface(profile, NULL, NULL, "Invalid named transition",
 825                             NULL, -EPROTO);
 826                 return -EPROTO;
 827         }
 828
 829         return 0;
 830 }
 831
 832 void aa_load_ent_free(struct aa_load_ent *ent)
 833 {
 834         if (ent) {
 835                 aa_put_profile(ent->rename);
 836                 aa_put_profile(ent->old);
 837                 aa_put_profile(ent->new);
 838                 kfree(ent->ns_name);
 839                 kzfree(ent);
 840         }
 841 }
 842
 843 struct aa_load_ent *aa_load_ent_alloc(void)
 844 {
 845         struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
 846         if (ent)
 847                 INIT_LIST_HEAD(&ent->list);
 848         return ent;
 849 }
 850
 851 /**
 852  * aa_unpack - unpack packed binary profile(s) data loaded from user space
 853  * @udata: user data copied to kmem  (NOT NULL)
 854  * @lh: list to place unpacked profiles in a aa_repl_ws
 855  * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
 856  *
 857  * Unpack user data and return refcounted allocated profile(s) stored in
 858  * @lh in order of discovery, with the list chain stored in base.list
 859  * or error
 860  *
 861  * Returns: profile(s) on @lh else error pointer if fails to unpack
 862  */
 863 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
 864               const char **ns)
 865 {
 866         struct aa_load_ent *tmp, *ent;
 867         struct aa_profile *profile = NULL;
 868         int error;
 869         struct aa_ext e = {
 870                 .start = udata->data,
 871                 .end = udata->data + udata->size,
 872                 .pos = udata->data,
 873         };
 874
 875         *ns = NULL;
 876         while (e.pos < e.end) {
 877                 char *ns_name = NULL;
 878                 void *start;
 879                 error = verify_header(&e, e.pos == e.start, ns);
 880                 if (error)
 881                         goto fail;
 882
 883                 start = e.pos;
 884                 profile = unpack_profile(&e, &ns_name);
 885                 if (IS_ERR(profile)) {
 886                         error = PTR_ERR(profile);
 887                         goto fail;
 888                 }
 889
 890                 error = verify_profile(profile);
 891                 if (error)
 892                         goto fail_profile;
 893
 894                 if (aa_g_hash_policy)
 895                         error = aa_calc_profile_hash(profile, e.version, start,
 896                                                      e.pos - start);
 897                 if (error)
 898                         goto fail_profile;
 899
 900                 ent = aa_load_ent_alloc();
 901                 if (!ent) {
 902                         error = -ENOMEM;
 903                         goto fail_profile;
 904                 }
 905
 906                 ent->new = profile;
 907                 ent->ns_name = ns_name;
 908                 list_add_tail(&ent->list, lh);
 909         }
 910         udata->abi = e.version & K_ABI_MASK;
 911         if (aa_g_hash_policy) {
 912                 udata->hash = aa_calc_hash(udata->data, udata->size);
 913                 if (IS_ERR(udata->hash)) {
 914                         error = PTR_ERR(udata->hash);
 915                         udata->hash = NULL;
 916                         goto fail;
 917                 }
 918         }
 919         return 0;
 920
 921 fail_profile:
 922         aa_put_profile(profile);
 923
 924 fail:
 925         list_for_each_entry_safe(ent, tmp, lh, list) {
 926                 list_del_init(&ent->list);
 927                 aa_load_ent_free(ent);
 928         }
 929
 930         return error;
 931 }