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 see Documentation/admin-guide/LSM/apparmor.rst
  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/cred.h"
  27 #include "include/crypto.h"
  28 #include "include/match.h"
  29 #include "include/path.h"
  30 #include "include/policy.h"
  31 #include "include/policy_unpack.h"
  32
  33 #define K_ABI_MASK 0x3ff
  34 #define FORCE_COMPLAIN_FLAG 0x800
  35 #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
  36 #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
  37
  38 #define v5      5       /* base version */
  39 #define v6      6       /* per entry policydb mediation check */
  40 #define v7      7
  41 #define v8      8       /* full network masking */
  42
  43 /*
  44  * The AppArmor interface treats data as a type byte followed by the
  45  * actual data.  The interface has the notion of a a named entry
  46  * which has a name (AA_NAME typecode followed by name string) followed by
  47  * the entries typecode and data.  Named types allow for optional
  48  * elements and extensions to be added and tested for without breaking
  49  * backwards compatibility.
  50  */
  51
  52 enum aa_code {
  53         AA_U8,
  54         AA_U16,
  55         AA_U32,
  56         AA_U64,
  57         AA_NAME,                /* same as string except it is items name */
  58         AA_STRING,
  59         AA_BLOB,
  60         AA_STRUCT,
  61         AA_STRUCTEND,
  62         AA_LIST,
  63         AA_LISTEND,
  64         AA_ARRAY,
  65         AA_ARRAYEND,
  66 };
  67
  68 /*
  69  * aa_ext is the read of the buffer containing the serialized profile.  The
  70  * data is copied into a kernel buffer in apparmorfs and then handed off to
  71  * the unpack routines.
  72  */
  73 struct aa_ext {
  74         void *start;
  75         void *end;
  76         void *pos;              /* pointer to current position in the buffer */
  77         u32 version;
  78 };
  79
  80 /* audit callback for unpack fields */
  81 static void audit_cb(struct audit_buffer *ab, void *va)
  82 {
  83         struct common_audit_data *sa = va;
  84
  85         if (aad(sa)->iface.ns) {
  86                 audit_log_format(ab, " ns=");
  87                 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
  88         }
  89         if (aad(sa)->name) {
  90                 audit_log_format(ab, " name=");
  91                 audit_log_untrustedstring(ab, aad(sa)->name);
  92         }
  93         if (aad(sa)->iface.pos)
  94                 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
  95 }
  96
  97 /**
  98  * audit_iface - do audit message for policy unpacking/load/replace/remove
  99  * @new: profile if it has been allocated (MAYBE NULL)
 100  * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
 101  * @name: name of the profile being manipulated (MAYBE NULL)
 102  * @info: any extra info about the failure (MAYBE NULL)
 103  * @e: buffer position info
 104  * @error: error code
 105  *
 106  * Returns: %0 or error
 107  */
 108 static int audit_iface(struct aa_profile *new, const char *ns_name,
 109                        const char *name, const char *info, struct aa_ext *e,
 110                        int error)
 111 {
 112         struct aa_profile *profile = labels_profile(aa_current_raw_label());
 113         DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
 114         if (e)
 115                 aad(&sa)->iface.pos = e->pos - e->start;
 116         aad(&sa)->iface.ns = ns_name;
 117         if (new)
 118                 aad(&sa)->name = new->base.hname;
 119         else
 120                 aad(&sa)->name = name;
 121         aad(&sa)->info = info;
 122         aad(&sa)->error = error;
 123
 124         return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
 125 }
 126
 127 void __aa_loaddata_update(struct aa_loaddata *data, long revision)
 128 {
 129         AA_BUG(!data);
 130         AA_BUG(!data->ns);
 131         AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
 132         AA_BUG(!mutex_is_locked(&data->ns->lock));
 133         AA_BUG(data->revision > revision);
 134
 135         data->revision = revision;
 136         d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
 137                 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
 138         d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
 139                 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
 140 }
 141
 142 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
 143 {
 144         if (l->size != r->size)
 145                 return false;
 146         if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
 147                 return false;
 148         return memcmp(l->data, r->data, r->size) == 0;
 149 }
 150
 151 /*
 152  * need to take the ns mutex lock which is NOT safe most places that
 153  * put_loaddata is called, so we have to delay freeing it
 154  */
 155 static void do_loaddata_free(struct work_struct *work)
 156 {
 157         struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
 158         struct aa_ns *ns = aa_get_ns(d->ns);
 159
 160         if (ns) {
 161                 mutex_lock_nested(&ns->lock, ns->level);
 162                 __aa_fs_remove_rawdata(d);
 163                 mutex_unlock(&ns->lock);
 164                 aa_put_ns(ns);
 165         }
 166
 167         kzfree(d->hash);
 168         kzfree(d->name);
 169         kvfree(d->data);
 170         kzfree(d);
 171 }
 172
 173 void aa_loaddata_kref(struct kref *kref)
 174 {
 175         struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
 176
 177         if (d) {
 178                 INIT_WORK(&d->work, do_loaddata_free);
 179                 schedule_work(&d->work);
 180         }
 181 }
 182
 183 struct aa_loaddata *aa_loaddata_alloc(size_t size)
 184 {
 185         struct aa_loaddata *d;
 186
 187         d = kzalloc(sizeof(*d), GFP_KERNEL);
 188         if (d == NULL)
 189                 return ERR_PTR(-ENOMEM);
 190         d->data = kvzalloc(size, GFP_KERNEL);
 191         if (!d->data) {
 192                 kfree(d);
 193                 return ERR_PTR(-ENOMEM);
 194         }
 195         kref_init(&d->count);
 196         INIT_LIST_HEAD(&d->list);
 197
 198         return d;
 199 }
 200
 201 /* test if read will be in packed data bounds */
 202 static bool inbounds(struct aa_ext *e, size_t size)
 203 {
 204         return (size <= e->end - e->pos);
 205 }
 206
 207 static void *kvmemdup(const void *src, size_t len)
 208 {
 209         void *p = kvmalloc(len, GFP_KERNEL);
 210
 211         if (p)
 212                 memcpy(p, src, len);
 213         return p;
 214 }
 215
 216 /**
 217  * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
 218  * @e: serialized data read head (NOT NULL)
 219  * @chunk: start address for chunk of data (NOT NULL)
 220  *
 221  * Returns: the size of chunk found with the read head at the end of the chunk.
 222  */
 223 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
 224 {
 225         size_t size = 0;
 226
 227         if (!inbounds(e, sizeof(u16)))
 228                 return 0;
 229         size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
 230         e->pos += sizeof(__le16);
 231         if (!inbounds(e, size))
 232                 return 0;
 233         *chunk = e->pos;
 234         e->pos += size;
 235         return size;
 236 }
 237
 238 /* unpack control byte */
 239 static bool unpack_X(struct aa_ext *e, enum aa_code code)
 240 {
 241         if (!inbounds(e, 1))
 242                 return 0;
 243         if (*(u8 *) e->pos != code)
 244                 return 0;
 245         e->pos++;
 246         return 1;
 247 }
 248
 249 /**
 250  * unpack_nameX - check is the next element is of type X with a name of @name
 251  * @e: serialized data extent information  (NOT NULL)
 252  * @code: type code
 253  * @name: name to match to the serialized element.  (MAYBE NULL)
 254  *
 255  * check that the next serialized data element is of type X and has a tag
 256  * name @name.  If @name is specified then there must be a matching
 257  * name element in the stream.  If @name is NULL any name element will be
 258  * skipped and only the typecode will be tested.
 259  *
 260  * Returns 1 on success (both type code and name tests match) and the read
 261  * head is advanced past the headers
 262  *
 263  * Returns: 0 if either match fails, the read head does not move
 264  */
 265 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
 266 {
 267         /*
 268          * May need to reset pos if name or type doesn't match
 269          */
 270         void *pos = e->pos;
 271         /*
 272          * Check for presence of a tagname, and if present name size
 273          * AA_NAME tag value is a u16.
 274          */
 275         if (unpack_X(e, AA_NAME)) {
 276                 char *tag = NULL;
 277                 size_t size = unpack_u16_chunk(e, &tag);
 278                 /* if a name is specified it must match. otherwise skip tag */
 279                 if (name && (!size || strcmp(name, tag)))
 280                         goto fail;
 281         } else if (name) {
 282                 /* if a name is specified and there is no name tag fail */
 283                 goto fail;
 284         }
 285
 286         /* now check if type code matches */
 287         if (unpack_X(e, code))
 288                 return 1;
 289
 290 fail:
 291         e->pos = pos;
 292         return 0;
 293 }
 294
 295 static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
 296 {
 297         if (unpack_nameX(e, AA_U8, name)) {
 298                 if (!inbounds(e, sizeof(u8)))
 299                         return 0;
 300                 if (data)
 301                         *data = get_unaligned((u8 *)e->pos);
 302                 e->pos += sizeof(u8);
 303                 return 1;
 304         }
 305         return 0;
 306 }
 307
 308 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
 309 {
 310         if (unpack_nameX(e, AA_U32, name)) {
 311                 if (!inbounds(e, sizeof(u32)))
 312                         return 0;
 313                 if (data)
 314                         *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 315                 e->pos += sizeof(u32);
 316                 return 1;
 317         }
 318         return 0;
 319 }
 320
 321 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
 322 {
 323         if (unpack_nameX(e, AA_U64, name)) {
 324                 if (!inbounds(e, sizeof(u64)))
 325                         return 0;
 326                 if (data)
 327                         *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
 328                 e->pos += sizeof(u64);
 329                 return 1;
 330         }
 331         return 0;
 332 }
 333
 334 static size_t unpack_array(struct aa_ext *e, const char *name)
 335 {
 336         if (unpack_nameX(e, AA_ARRAY, name)) {
 337                 int size;
 338                 if (!inbounds(e, sizeof(u16)))
 339                         return 0;
 340                 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
 341                 e->pos += sizeof(u16);
 342                 return size;
 343         }
 344         return 0;
 345 }
 346
 347 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
 348 {
 349         if (unpack_nameX(e, AA_BLOB, name)) {
 350                 u32 size;
 351                 if (!inbounds(e, sizeof(u32)))
 352                         return 0;
 353                 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
 354                 e->pos += sizeof(u32);
 355                 if (inbounds(e, (size_t) size)) {
 356                         *blob = e->pos;
 357                         e->pos += size;
 358                         return size;
 359                 }
 360         }
 361         return 0;
 362 }
 363
 364 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
 365 {
 366         char *src_str;
 367         size_t size = 0;
 368         void *pos = e->pos;
 369         *string = NULL;
 370         if (unpack_nameX(e, AA_STRING, name)) {
 371                 size = unpack_u16_chunk(e, &src_str);
 372                 if (size) {
 373                         /* strings are null terminated, length is size - 1 */
 374                         if (src_str[size - 1] != 0)
 375                                 goto fail;
 376                         *string = src_str;
 377                 }
 378         }
 379         return size;
 380
 381 fail:
 382         e->pos = pos;
 383         return 0;
 384 }
 385
 386 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
 387 {
 388         const char *tmp;
 389         void *pos = e->pos;
 390         int res = unpack_str(e, &tmp, name);
 391         *string = NULL;
 392
 393         if (!res)
 394                 return 0;
 395
 396         *string = kmemdup(tmp, res, GFP_KERNEL);
 397         if (!*string) {
 398                 e->pos = pos;
 399                 return 0;
 400         }
 401
 402         return res;
 403 }
 404
 405
 406 /**
 407  * unpack_dfa - unpack a file rule dfa
 408  * @e: serialized data extent information (NOT NULL)
 409  *
 410  * returns dfa or ERR_PTR or NULL if no dfa
 411  */
 412 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
 413 {
 414         char *blob = NULL;
 415         size_t size;
 416         struct aa_dfa *dfa = NULL;
 417
 418         size = unpack_blob(e, &blob, "aadfa");
 419         if (size) {
 420                 /*
 421                  * The dfa is aligned with in the blob to 8 bytes
 422                  * from the beginning of the stream.
 423                  * alignment adjust needed by dfa unpack
 424                  */
 425                 size_t sz = blob - (char *) e->start -
 426                         ((e->pos - e->start) & 7);
 427                 size_t pad = ALIGN(sz, 8) - sz;
 428                 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
 429                         TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
 430                 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
 431
 432                 if (IS_ERR(dfa))
 433                         return dfa;
 434
 435         }
 436
 437         return dfa;
 438 }
 439
 440 /**
 441  * unpack_trans_table - unpack a profile transition table
 442  * @e: serialized data extent information  (NOT NULL)
 443  * @profile: profile to add the accept table to (NOT NULL)
 444  *
 445  * Returns: 1 if table successfully unpacked
 446  */
 447 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
 448 {
 449         void *saved_pos = e->pos;
 450
 451         /* exec table is optional */
 452         if (unpack_nameX(e, AA_STRUCT, "xtable")) {
 453                 int i, size;
 454
 455                 size = unpack_array(e, NULL);
 456                 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
 457                 if (size > 16 - 4)
 458                         goto fail;
 459                 profile->file.trans.table = kcalloc(size, sizeof(char *),
 460                                                     GFP_KERNEL);
 461                 if (!profile->file.trans.table)
 462                         goto fail;
 463
 464                 profile->file.trans.size = size;
 465                 for (i = 0; i < size; i++) {
 466                         char *str;
 467                         int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
 468                         /* unpack_strdup verifies that the last character is
 469                          * null termination byte.
 470                          */
 471                         if (!size2)
 472                                 goto fail;
 473                         profile->file.trans.table[i] = str;
 474                         /* verify that name doesn't start with space */
 475                         if (isspace(*str))
 476                                 goto fail;
 477
 478                         /* count internal #  of internal \0 */
 479                         for (c = j = 0; j < size2 - 1; j++) {
 480                                 if (!str[j]) {
 481                                         pos = j;
 482                                         c++;
 483                                 }
 484                         }
 485                         if (*str == ':') {
 486                                 /* first character after : must be valid */
 487                                 if (!str[1])
 488                                         goto fail;
 489                                 /* beginning with : requires an embedded \0,
 490                                  * verify that exactly 1 internal \0 exists
 491                                  * trailing \0 already verified by unpack_strdup
 492                                  *
 493                                  * convert \0 back to : for label_parse
 494                                  */
 495                                 if (c == 1)
 496                                         str[pos] = ':';
 497                                 else if (c > 1)
 498                                         goto fail;
 499                         } else if (c)
 500                                 /* fail - all other cases with embedded \0 */
 501                                 goto fail;
 502                 }
 503                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 504                         goto fail;
 505                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 506                         goto fail;
 507         }
 508         return 1;
 509
 510 fail:
 511         aa_free_domain_entries(&profile->file.trans);
 512         e->pos = saved_pos;
 513         return 0;
 514 }
 515
 516 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
 517 {
 518         void *pos = e->pos;
 519
 520         if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
 521                 int i, size;
 522
 523                 size = unpack_array(e, NULL);
 524                 profile->xattr_count = size;
 525                 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
 526                 if (!profile->xattrs)
 527                         goto fail;
 528                 for (i = 0; i < size; i++) {
 529                         if (!unpack_strdup(e, &profile->xattrs[i], NULL))
 530                                 goto fail;
 531                 }
 532                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 533                         goto fail;
 534                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 535                         goto fail;
 536         }
 537
 538         return 1;
 539
 540 fail:
 541         e->pos = pos;
 542         return 0;
 543 }
 544
 545 static bool unpack_secmark(struct aa_ext *e, struct aa_profile *profile)
 546 {
 547         void *pos = e->pos;
 548         int i, size;
 549
 550         if (unpack_nameX(e, AA_STRUCT, "secmark")) {
 551                 size = unpack_array(e, NULL);
 552
 553                 profile->secmark = kcalloc(size, sizeof(struct aa_secmark),
 554                                            GFP_KERNEL);
 555                 if (!profile->secmark)
 556                         goto fail;
 557
 558                 profile->secmark_count = size;
 559
 560                 for (i = 0; i < size; i++) {
 561                         if (!unpack_u8(e, &profile->secmark[i].audit, NULL))
 562                                 goto fail;
 563                         if (!unpack_u8(e, &profile->secmark[i].deny, NULL))
 564                                 goto fail;
 565                         if (!unpack_strdup(e, &profile->secmark[i].label, NULL))
 566                                 goto fail;
 567                 }
 568                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 569                         goto fail;
 570                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 571                         goto fail;
 572         }
 573
 574         return 1;
 575
 576 fail:
 577         if (profile->secmark) {
 578                 for (i = 0; i < size; i++)
 579                         kfree(profile->secmark[i].label);
 580                 kfree(profile->secmark);
 581                 profile->secmark_count = 0;
 582                 profile->secmark = NULL;
 583         }
 584
 585         e->pos = pos;
 586         return 0;
 587 }
 588
 589 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
 590 {
 591         void *pos = e->pos;
 592
 593         /* rlimits are optional */
 594         if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
 595                 int i, size;
 596                 u32 tmp = 0;
 597                 if (!unpack_u32(e, &tmp, NULL))
 598                         goto fail;
 599                 profile->rlimits.mask = tmp;
 600
 601                 size = unpack_array(e, NULL);
 602                 if (size > RLIM_NLIMITS)
 603                         goto fail;
 604                 for (i = 0; i < size; i++) {
 605                         u64 tmp2 = 0;
 606                         int a = aa_map_resource(i);
 607                         if (!unpack_u64(e, &tmp2, NULL))
 608                                 goto fail;
 609                         profile->rlimits.limits[a].rlim_max = tmp2;
 610                 }
 611                 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
 612                         goto fail;
 613                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 614                         goto fail;
 615         }
 616         return 1;
 617
 618 fail:
 619         e->pos = pos;
 620         return 0;
 621 }
 622
 623 static u32 strhash(const void *data, u32 len, u32 seed)
 624 {
 625         const char * const *key = data;
 626
 627         return jhash(*key, strlen(*key), seed);
 628 }
 629
 630 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
 631 {
 632         const struct aa_data *data = obj;
 633         const char * const *key = arg->key;
 634
 635         return strcmp(data->key, *key);
 636 }
 637
 638 /**
 639  * unpack_profile - unpack a serialized profile
 640  * @e: serialized data extent information (NOT NULL)
 641  *
 642  * NOTE: unpack profile sets audit struct if there is a failure
 643  */
 644 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
 645 {
 646         struct aa_profile *profile = NULL;
 647         const char *tmpname, *tmpns = NULL, *name = NULL;
 648         const char *info = "failed to unpack profile";
 649         size_t ns_len;
 650         struct rhashtable_params params = { 0 };
 651         char *key = NULL;
 652         struct aa_data *data;
 653         int i, error = -EPROTO;
 654         kernel_cap_t tmpcap;
 655         u32 tmp;
 656
 657         *ns_name = NULL;
 658
 659         /* check that we have the right struct being passed */
 660         if (!unpack_nameX(e, AA_STRUCT, "profile"))
 661                 goto fail;
 662         if (!unpack_str(e, &name, NULL))
 663                 goto fail;
 664         if (*name == '\0')
 665                 goto fail;
 666
 667         tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
 668         if (tmpns) {
 669                 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
 670                 if (!*ns_name) {
 671                         info = "out of memory";
 672                         goto fail;
 673                 }
 674                 name = tmpname;
 675         }
 676
 677         profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
 678         if (!profile)
 679                 return ERR_PTR(-ENOMEM);
 680
 681         /* profile renaming is optional */
 682         (void) unpack_str(e, &profile->rename, "rename");
 683
 684         /* attachment string is optional */
 685         (void) unpack_str(e, &profile->attach, "attach");
 686
 687         /* xmatch is optional and may be NULL */
 688         profile->xmatch = unpack_dfa(e);
 689         if (IS_ERR(profile->xmatch)) {
 690                 error = PTR_ERR(profile->xmatch);
 691                 profile->xmatch = NULL;
 692                 info = "bad xmatch";
 693                 goto fail;
 694         }
 695         /* xmatch_len is not optional if xmatch is set */
 696         if (profile->xmatch) {
 697                 if (!unpack_u32(e, &tmp, NULL)) {
 698                         info = "missing xmatch len";
 699                         goto fail;
 700                 }
 701                 profile->xmatch_len = tmp;
 702         }
 703
 704         /* disconnected attachment string is optional */
 705         (void) unpack_str(e, &profile->disconnected, "disconnected");
 706
 707         /* per profile debug flags (complain, audit) */
 708         if (!unpack_nameX(e, AA_STRUCT, "flags")) {
 709                 info = "profile missing flags";
 710                 goto fail;
 711         }
 712         info = "failed to unpack profile flags";
 713         if (!unpack_u32(e, &tmp, NULL))
 714                 goto fail;
 715         if (tmp & PACKED_FLAG_HAT)
 716                 profile->label.flags |= FLAG_HAT;
 717         if (!unpack_u32(e, &tmp, NULL))
 718                 goto fail;
 719         if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
 720                 profile->mode = APPARMOR_COMPLAIN;
 721         else if (tmp == PACKED_MODE_KILL)
 722                 profile->mode = APPARMOR_KILL;
 723         else if (tmp == PACKED_MODE_UNCONFINED)
 724                 profile->mode = APPARMOR_UNCONFINED;
 725         if (!unpack_u32(e, &tmp, NULL))
 726                 goto fail;
 727         if (tmp)
 728                 profile->audit = AUDIT_ALL;
 729
 730         if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 731                 goto fail;
 732
 733         /* path_flags is optional */
 734         if (unpack_u32(e, &profile->path_flags, "path_flags"))
 735                 profile->path_flags |= profile->label.flags &
 736                         PATH_MEDIATE_DELETED;
 737         else
 738                 /* set a default value if path_flags field is not present */
 739                 profile->path_flags = PATH_MEDIATE_DELETED;
 740
 741         info = "failed to unpack profile capabilities";
 742         if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
 743                 goto fail;
 744         if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
 745                 goto fail;
 746         if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
 747                 goto fail;
 748         if (!unpack_u32(e, &tmpcap.cap[0], NULL))
 749                 goto fail;
 750
 751         info = "failed to unpack upper profile capabilities";
 752         if (unpack_nameX(e, AA_STRUCT, "caps64")) {
 753                 /* optional upper half of 64 bit caps */
 754                 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
 755                         goto fail;
 756                 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
 757                         goto fail;
 758                 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
 759                         goto fail;
 760                 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
 761                         goto fail;
 762                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 763                         goto fail;
 764         }
 765
 766         info = "failed to unpack extended profile capabilities";
 767         if (unpack_nameX(e, AA_STRUCT, "capsx")) {
 768                 /* optional extended caps mediation mask */
 769                 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
 770                         goto fail;
 771                 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
 772                         goto fail;
 773                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 774                         goto fail;
 775         }
 776
 777         if (!unpack_xattrs(e, profile)) {
 778                 info = "failed to unpack profile xattrs";
 779                 goto fail;
 780         }
 781
 782         if (!unpack_rlimits(e, profile)) {
 783                 info = "failed to unpack profile rlimits";
 784                 goto fail;
 785         }
 786
 787         if (!unpack_secmark(e, profile)) {
 788                 info = "failed to unpack profile secmark rules";
 789                 goto fail;
 790         }
 791
 792         if (unpack_nameX(e, AA_STRUCT, "policydb")) {
 793                 /* generic policy dfa - optional and may be NULL */
 794                 info = "failed to unpack policydb";
 795                 profile->policy.dfa = unpack_dfa(e);
 796                 if (IS_ERR(profile->policy.dfa)) {
 797                         error = PTR_ERR(profile->policy.dfa);
 798                         profile->policy.dfa = NULL;
 799                         goto fail;
 800                 } else if (!profile->policy.dfa) {
 801                         error = -EPROTO;
 802                         goto fail;
 803                 }
 804                 if (!unpack_u32(e, &profile->policy.start[0], "start"))
 805                         /* default start state */
 806                         profile->policy.start[0] = DFA_START;
 807                 /* setup class index */
 808                 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
 809                         profile->policy.start[i] =
 810                                 aa_dfa_next(profile->policy.dfa,
 811                                             profile->policy.start[0],
 812                                             i);
 813                 }
 814                 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
 815                         goto fail;
 816         } else
 817                 profile->policy.dfa = aa_get_dfa(nulldfa);
 818
 819         /* get file rules */
 820         profile->file.dfa = unpack_dfa(e);
 821         if (IS_ERR(profile->file.dfa)) {
 822                 error = PTR_ERR(profile->file.dfa);
 823                 profile->file.dfa = NULL;
 824                 info = "failed to unpack profile file rules";
 825                 goto fail;
 826         } else if (profile->file.dfa) {
 827                 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
 828                         /* default start state */
 829                         profile->file.start = DFA_START;
 830         } else if (profile->policy.dfa &&
 831                    profile->policy.start[AA_CLASS_FILE]) {
 832                 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
 833                 profile->file.start = profile->policy.start[AA_CLASS_FILE];
 834         } else
 835                 profile->file.dfa = aa_get_dfa(nulldfa);
 836
 837         if (!unpack_trans_table(e, profile)) {
 838                 info = "failed to unpack profile transition table";
 839                 goto fail;
 840         }
 841
 842         if (unpack_nameX(e, AA_STRUCT, "data")) {
 843                 info = "out of memory";
 844                 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
 845                 if (!profile->data)
 846                         goto fail;
 847
 848                 params.nelem_hint = 3;
 849                 params.key_len = sizeof(void *);
 850                 params.key_offset = offsetof(struct aa_data, key);
 851                 params.head_offset = offsetof(struct aa_data, head);
 852                 params.hashfn = strhash;
 853                 params.obj_cmpfn = datacmp;
 854
 855                 if (rhashtable_init(profile->data, &params)) {
 856                         info = "failed to init key, value hash table";
 857                         goto fail;
 858                 }
 859
 860                 while (unpack_strdup(e, &key, NULL)) {
 861                         data = kzalloc(sizeof(*data), GFP_KERNEL);
 862                         if (!data) {
 863                                 kzfree(key);
 864                                 goto fail;
 865                         }
 866
 867                         data->key = key;
 868                         data->size = unpack_blob(e, &data->data, NULL);
 869                         data->data = kvmemdup(data->data, data->size);
 870                         if (data->size && !data->data) {
 871                                 kzfree(data->key);
 872                                 kzfree(data);
 873                                 goto fail;
 874                         }
 875
 876                         rhashtable_insert_fast(profile->data, &data->head,
 877                                                profile->data->p);
 878                 }
 879
 880                 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
 881                         info = "failed to unpack end of key, value data table";
 882                         goto fail;
 883                 }
 884         }
 885
 886         if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
 887                 info = "failed to unpack end of profile";
 888                 goto fail;
 889         }
 890
 891         return profile;
 892
 893 fail:
 894         if (profile)
 895                 name = NULL;
 896         else if (!name)
 897                 name = "unknown";
 898         audit_iface(profile, NULL, name, info, e, error);
 899         aa_free_profile(profile);
 900
 901         return ERR_PTR(error);
 902 }
 903
 904 /**
 905  * verify_head - unpack serialized stream header
 906  * @e: serialized data read head (NOT NULL)
 907  * @required: whether the header is required or optional
 908  * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
 909  *
 910  * Returns: error or 0 if header is good
 911  */
 912 static int verify_header(struct aa_ext *e, int required, const char **ns)
 913 {
 914         int error = -EPROTONOSUPPORT;
 915         const char *name = NULL;
 916         *ns = NULL;
 917
 918         /* get the interface version */
 919         if (!unpack_u32(e, &e->version, "version")) {
 920                 if (required) {
 921                         audit_iface(NULL, NULL, NULL, "invalid profile format",
 922                                     e, error);
 923                         return error;
 924                 }
 925         }
 926
 927         /* Check that the interface version is currently supported.
 928          * if not specified use previous version
 929          * Mask off everything that is not kernel abi version
 930          */
 931         if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
 932                 audit_iface(NULL, NULL, NULL, "unsupported interface version",
 933                             e, error);
 934                 return error;
 935         }
 936
 937         /* read the namespace if present */
 938         if (unpack_str(e, &name, "namespace")) {
 939                 if (*name == '\0') {
 940                         audit_iface(NULL, NULL, NULL, "invalid namespace name",
 941                                     e, error);
 942                         return error;
 943                 }
 944                 if (*ns && strcmp(*ns, name))
 945                         audit_iface(NULL, NULL, NULL, "invalid ns change", e,
 946                                     error);
 947                 else if (!*ns)
 948                         *ns = name;
 949         }
 950
 951         return 0;
 952 }
 953
 954 static bool verify_xindex(int xindex, int table_size)
 955 {
 956         int index, xtype;
 957         xtype = xindex & AA_X_TYPE_MASK;
 958         index = xindex & AA_X_INDEX_MASK;
 959         if (xtype == AA_X_TABLE && index >= table_size)
 960                 return 0;
 961         return 1;
 962 }
 963
 964 /* verify dfa xindexes are in range of transition tables */
 965 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
 966 {
 967         int i;
 968         for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
 969                 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
 970                         return 0;
 971                 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
 972                         return 0;
 973         }
 974         return 1;
 975 }
 976
 977 /**
 978  * verify_profile - Do post unpack analysis to verify profile consistency
 979  * @profile: profile to verify (NOT NULL)
 980  *
 981  * Returns: 0 if passes verification else error
 982  */
 983 static int verify_profile(struct aa_profile *profile)
 984 {
 985         if (profile->file.dfa &&
 986             !verify_dfa_xindex(profile->file.dfa,
 987                                profile->file.trans.size)) {
 988                 audit_iface(profile, NULL, NULL, "Invalid named transition",
 989                             NULL, -EPROTO);
 990                 return -EPROTO;
 991         }
 992
 993         return 0;
 994 }
 995
 996 void aa_load_ent_free(struct aa_load_ent *ent)
 997 {
 998         if (ent) {
 999                 aa_put_profile(ent->rename);
1000                 aa_put_profile(ent->old);
1001                 aa_put_profile(ent->new);
1002                 kfree(ent->ns_name);
1003                 kzfree(ent);
1004         }
1005 }
1006
1007 struct aa_load_ent *aa_load_ent_alloc(void)
1008 {
1009         struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1010         if (ent)
1011                 INIT_LIST_HEAD(&ent->list);
1012         return ent;
1013 }
1014
1015 /**
1016  * aa_unpack - unpack packed binary profile(s) data loaded from user space
1017  * @udata: user data copied to kmem  (NOT NULL)
1018  * @lh: list to place unpacked profiles in a aa_repl_ws
1019  * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1020  *
1021  * Unpack user data and return refcounted allocated profile(s) stored in
1022  * @lh in order of discovery, with the list chain stored in base.list
1023  * or error
1024  *
1025  * Returns: profile(s) on @lh else error pointer if fails to unpack
1026  */
1027 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1028               const char **ns)
1029 {
1030         struct aa_load_ent *tmp, *ent;
1031         struct aa_profile *profile = NULL;
1032         int error;
1033         struct aa_ext e = {
1034                 .start = udata->data,
1035                 .end = udata->data + udata->size,
1036                 .pos = udata->data,
1037         };
1038
1039         *ns = NULL;
1040         while (e.pos < e.end) {
1041                 char *ns_name = NULL;
1042                 void *start;
1043                 error = verify_header(&e, e.pos == e.start, ns);
1044                 if (error)
1045                         goto fail;
1046
1047                 start = e.pos;
1048                 profile = unpack_profile(&e, &ns_name);
1049                 if (IS_ERR(profile)) {
1050                         error = PTR_ERR(profile);
1051                         goto fail;
1052                 }
1053
1054                 error = verify_profile(profile);
1055                 if (error)
1056                         goto fail_profile;
1057
1058                 if (aa_g_hash_policy)
1059                         error = aa_calc_profile_hash(profile, e.version, start,
1060                                                      e.pos - start);
1061                 if (error)
1062                         goto fail_profile;
1063
1064                 ent = aa_load_ent_alloc();
1065                 if (!ent) {
1066                         error = -ENOMEM;
1067                         goto fail_profile;
1068                 }
1069
1070                 ent->new = profile;
1071                 ent->ns_name = ns_name;
1072                 list_add_tail(&ent->list, lh);
1073         }
1074         udata->abi = e.version & K_ABI_MASK;
1075         if (aa_g_hash_policy) {
1076                 udata->hash = aa_calc_hash(udata->data, udata->size);
1077                 if (IS_ERR(udata->hash)) {
1078                         error = PTR_ERR(udata->hash);
1079                         udata->hash = NULL;
1080                         goto fail;
1081                 }
1082         }
1083         return 0;
1084
1085 fail_profile:
1086         aa_put_profile(profile);
1087
1088 fail:
1089         list_for_each_entry_safe(ent, tmp, lh, list) {
1090                 list_del_init(&ent->list);
1091                 aa_load_ent_free(ent);
1092         }
1093
1094         return error;
1095 }