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_u32(struct aa_ext *e, u32 *data, const char *name) 296 { 297 if (unpack_nameX(e, AA_U32, name)) { 298 if (!inbounds(e, sizeof(u32))) 299 return 0; 300 if (data) 301 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 302 e->pos += sizeof(u32); 303 return 1; 304 } 305 return 0; 306 } 307 308 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name) 309 { 310 if (unpack_nameX(e, AA_U64, name)) { 311 if (!inbounds(e, sizeof(u64))) 312 return 0; 313 if (data) 314 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos)); 315 e->pos += sizeof(u64); 316 return 1; 317 } 318 return 0; 319 } 320 321 static size_t unpack_array(struct aa_ext *e, const char *name) 322 { 323 if (unpack_nameX(e, AA_ARRAY, name)) { 324 int size; 325 if (!inbounds(e, sizeof(u16))) 326 return 0; 327 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos)); 328 e->pos += sizeof(u16); 329 return size; 330 } 331 return 0; 332 } 333 334 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name) 335 { 336 if (unpack_nameX(e, AA_BLOB, name)) { 337 u32 size; 338 if (!inbounds(e, sizeof(u32))) 339 return 0; 340 size = le32_to_cpu(get_unaligned((__le32 *) e->pos)); 341 e->pos += sizeof(u32); 342 if (inbounds(e, (size_t) size)) { 343 *blob = e->pos; 344 e->pos += size; 345 return size; 346 } 347 } 348 return 0; 349 } 350 351 static int unpack_str(struct aa_ext *e, const char **string, const char *name) 352 { 353 char *src_str; 354 size_t size = 0; 355 void *pos = e->pos; 356 *string = NULL; 357 if (unpack_nameX(e, AA_STRING, name)) { 358 size = unpack_u16_chunk(e, &src_str); 359 if (size) { 360 /* strings are null terminated, length is size - 1 */ 361 if (src_str[size - 1] != 0) 362 goto fail; 363 *string = src_str; 364 } 365 } 366 return size; 367 368 fail: 369 e->pos = pos; 370 return 0; 371 } 372 373 static int unpack_strdup(struct aa_ext *e, char **string, const char *name) 374 { 375 const char *tmp; 376 void *pos = e->pos; 377 int res = unpack_str(e, &tmp, name); 378 *string = NULL; 379 380 if (!res) 381 return 0; 382 383 *string = kmemdup(tmp, res, GFP_KERNEL); 384 if (!*string) { 385 e->pos = pos; 386 return 0; 387 } 388 389 return res; 390 } 391 392 393 /** 394 * unpack_dfa - unpack a file rule dfa 395 * @e: serialized data extent information (NOT NULL) 396 * 397 * returns dfa or ERR_PTR or NULL if no dfa 398 */ 399 static struct aa_dfa *unpack_dfa(struct aa_ext *e) 400 { 401 char *blob = NULL; 402 size_t size; 403 struct aa_dfa *dfa = NULL; 404 405 size = unpack_blob(e, &blob, "aadfa"); 406 if (size) { 407 /* 408 * The dfa is aligned with in the blob to 8 bytes 409 * from the beginning of the stream. 410 * alignment adjust needed by dfa unpack 411 */ 412 size_t sz = blob - (char *) e->start - 413 ((e->pos - e->start) & 7); 414 size_t pad = ALIGN(sz, 8) - sz; 415 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) | 416 TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES; 417 dfa = aa_dfa_unpack(blob + pad, size - pad, flags); 418 419 if (IS_ERR(dfa)) 420 return dfa; 421 422 } 423 424 return dfa; 425 } 426 427 /** 428 * unpack_trans_table - unpack a profile transition table 429 * @e: serialized data extent information (NOT NULL) 430 * @profile: profile to add the accept table to (NOT NULL) 431 * 432 * Returns: 1 if table successfully unpacked 433 */ 434 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile) 435 { 436 void *saved_pos = e->pos; 437 438 /* exec table is optional */ 439 if (unpack_nameX(e, AA_STRUCT, "xtable")) { 440 int i, size; 441 442 size = unpack_array(e, NULL); 443 /* currently 4 exec bits and entries 0-3 are reserved iupcx */ 444 if (size > 16 - 4) 445 goto fail; 446 profile->file.trans.table = kcalloc(size, sizeof(char *), 447 GFP_KERNEL); 448 if (!profile->file.trans.table) 449 goto fail; 450 451 profile->file.trans.size = size; 452 for (i = 0; i < size; i++) { 453 char *str; 454 int c, j, pos, size2 = unpack_strdup(e, &str, NULL); 455 /* unpack_strdup verifies that the last character is 456 * null termination byte. 457 */ 458 if (!size2) 459 goto fail; 460 profile->file.trans.table[i] = str; 461 /* verify that name doesn't start with space */ 462 if (isspace(*str)) 463 goto fail; 464 465 /* count internal # of internal \0 */ 466 for (c = j = 0; j < size2 - 1; j++) { 467 if (!str[j]) { 468 pos = j; 469 c++; 470 } 471 } 472 if (*str == ':') { 473 /* first character after : must be valid */ 474 if (!str[1]) 475 goto fail; 476 /* beginning with : requires an embedded \0, 477 * verify that exactly 1 internal \0 exists 478 * trailing \0 already verified by unpack_strdup 479 * 480 * convert \0 back to : for label_parse 481 */ 482 if (c == 1) 483 str[pos] = ':'; 484 else if (c > 1) 485 goto fail; 486 } else if (c) 487 /* fail - all other cases with embedded \0 */ 488 goto fail; 489 } 490 if (!unpack_nameX(e, AA_ARRAYEND, NULL)) 491 goto fail; 492 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 493 goto fail; 494 } 495 return 1; 496 497 fail: 498 aa_free_domain_entries(&profile->file.trans); 499 e->pos = saved_pos; 500 return 0; 501 } 502 503 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile) 504 { 505 void *pos = e->pos; 506 507 if (unpack_nameX(e, AA_STRUCT, "xattrs")) { 508 int i, size; 509 510 size = unpack_array(e, NULL); 511 profile->xattr_count = size; 512 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL); 513 if (!profile->xattrs) 514 goto fail; 515 for (i = 0; i < size; i++) { 516 if (!unpack_strdup(e, &profile->xattrs[i], NULL)) 517 goto fail; 518 } 519 if (!unpack_nameX(e, AA_ARRAYEND, NULL)) 520 goto fail; 521 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 522 goto fail; 523 } 524 525 return 1; 526 527 fail: 528 e->pos = pos; 529 return 0; 530 } 531 532 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile) 533 { 534 void *pos = e->pos; 535 536 /* rlimits are optional */ 537 if (unpack_nameX(e, AA_STRUCT, "rlimits")) { 538 int i, size; 539 u32 tmp = 0; 540 if (!unpack_u32(e, &tmp, NULL)) 541 goto fail; 542 profile->rlimits.mask = tmp; 543 544 size = unpack_array(e, NULL); 545 if (size > RLIM_NLIMITS) 546 goto fail; 547 for (i = 0; i < size; i++) { 548 u64 tmp2 = 0; 549 int a = aa_map_resource(i); 550 if (!unpack_u64(e, &tmp2, NULL)) 551 goto fail; 552 profile->rlimits.limits[a].rlim_max = tmp2; 553 } 554 if (!unpack_nameX(e, AA_ARRAYEND, NULL)) 555 goto fail; 556 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 557 goto fail; 558 } 559 return 1; 560 561 fail: 562 e->pos = pos; 563 return 0; 564 } 565 566 static u32 strhash(const void *data, u32 len, u32 seed) 567 { 568 const char * const *key = data; 569 570 return jhash(*key, strlen(*key), seed); 571 } 572 573 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj) 574 { 575 const struct aa_data *data = obj; 576 const char * const *key = arg->key; 577 578 return strcmp(data->key, *key); 579 } 580 581 /** 582 * unpack_profile - unpack a serialized profile 583 * @e: serialized data extent information (NOT NULL) 584 * 585 * NOTE: unpack profile sets audit struct if there is a failure 586 */ 587 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) 588 { 589 struct aa_profile *profile = NULL; 590 const char *tmpname, *tmpns = NULL, *name = NULL; 591 const char *info = "failed to unpack profile"; 592 size_t ns_len; 593 struct rhashtable_params params = { 0 }; 594 char *key = NULL; 595 struct aa_data *data; 596 int i, error = -EPROTO; 597 kernel_cap_t tmpcap; 598 u32 tmp; 599 600 *ns_name = NULL; 601 602 /* check that we have the right struct being passed */ 603 if (!unpack_nameX(e, AA_STRUCT, "profile")) 604 goto fail; 605 if (!unpack_str(e, &name, NULL)) 606 goto fail; 607 if (*name == '\0') 608 goto fail; 609 610 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); 611 if (tmpns) { 612 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); 613 if (!*ns_name) { 614 info = "out of memory"; 615 goto fail; 616 } 617 name = tmpname; 618 } 619 620 profile = aa_alloc_profile(name, NULL, GFP_KERNEL); 621 if (!profile) 622 return ERR_PTR(-ENOMEM); 623 624 /* profile renaming is optional */ 625 (void) unpack_str(e, &profile->rename, "rename"); 626 627 /* attachment string is optional */ 628 (void) unpack_str(e, &profile->attach, "attach"); 629 630 /* xmatch is optional and may be NULL */ 631 profile->xmatch = unpack_dfa(e); 632 if (IS_ERR(profile->xmatch)) { 633 error = PTR_ERR(profile->xmatch); 634 profile->xmatch = NULL; 635 info = "bad xmatch"; 636 goto fail; 637 } 638 /* xmatch_len is not optional if xmatch is set */ 639 if (profile->xmatch) { 640 if (!unpack_u32(e, &tmp, NULL)) { 641 info = "missing xmatch len"; 642 goto fail; 643 } 644 profile->xmatch_len = tmp; 645 } 646 647 /* disconnected attachment string is optional */ 648 (void) unpack_str(e, &profile->disconnected, "disconnected"); 649 650 /* per profile debug flags (complain, audit) */ 651 if (!unpack_nameX(e, AA_STRUCT, "flags")) { 652 info = "profile missing flags"; 653 goto fail; 654 } 655 info = "failed to unpack profile flags"; 656 if (!unpack_u32(e, &tmp, NULL)) 657 goto fail; 658 if (tmp & PACKED_FLAG_HAT) 659 profile->label.flags |= FLAG_HAT; 660 if (!unpack_u32(e, &tmp, NULL)) 661 goto fail; 662 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) 663 profile->mode = APPARMOR_COMPLAIN; 664 else if (tmp == PACKED_MODE_KILL) 665 profile->mode = APPARMOR_KILL; 666 else if (tmp == PACKED_MODE_UNCONFINED) 667 profile->mode = APPARMOR_UNCONFINED; 668 if (!unpack_u32(e, &tmp, NULL)) 669 goto fail; 670 if (tmp) 671 profile->audit = AUDIT_ALL; 672 673 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 674 goto fail; 675 676 /* path_flags is optional */ 677 if (unpack_u32(e, &profile->path_flags, "path_flags")) 678 profile->path_flags |= profile->label.flags & 679 PATH_MEDIATE_DELETED; 680 else 681 /* set a default value if path_flags field is not present */ 682 profile->path_flags = PATH_MEDIATE_DELETED; 683 684 info = "failed to unpack profile capabilities"; 685 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL)) 686 goto fail; 687 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL)) 688 goto fail; 689 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL)) 690 goto fail; 691 if (!unpack_u32(e, &tmpcap.cap[0], NULL)) 692 goto fail; 693 694 info = "failed to unpack upper profile capabilities"; 695 if (unpack_nameX(e, AA_STRUCT, "caps64")) { 696 /* optional upper half of 64 bit caps */ 697 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL)) 698 goto fail; 699 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL)) 700 goto fail; 701 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL)) 702 goto fail; 703 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL)) 704 goto fail; 705 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 706 goto fail; 707 } 708 709 info = "failed to unpack extended profile capabilities"; 710 if (unpack_nameX(e, AA_STRUCT, "capsx")) { 711 /* optional extended caps mediation mask */ 712 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL)) 713 goto fail; 714 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL)) 715 goto fail; 716 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 717 goto fail; 718 } 719 720 if (!unpack_xattrs(e, profile)) { 721 info = "failed to unpack profile xattrs"; 722 goto fail; 723 } 724 725 if (!unpack_rlimits(e, profile)) { 726 info = "failed to unpack profile rlimits"; 727 goto fail; 728 } 729 730 if (unpack_nameX(e, AA_STRUCT, "policydb")) { 731 /* generic policy dfa - optional and may be NULL */ 732 info = "failed to unpack policydb"; 733 profile->policy.dfa = unpack_dfa(e); 734 if (IS_ERR(profile->policy.dfa)) { 735 error = PTR_ERR(profile->policy.dfa); 736 profile->policy.dfa = NULL; 737 goto fail; 738 } else if (!profile->policy.dfa) { 739 error = -EPROTO; 740 goto fail; 741 } 742 if (!unpack_u32(e, &profile->policy.start[0], "start")) 743 /* default start state */ 744 profile->policy.start[0] = DFA_START; 745 /* setup class index */ 746 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) { 747 profile->policy.start[i] = 748 aa_dfa_next(profile->policy.dfa, 749 profile->policy.start[0], 750 i); 751 } 752 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) 753 goto fail; 754 } else 755 profile->policy.dfa = aa_get_dfa(nulldfa); 756 757 /* get file rules */ 758 profile->file.dfa = unpack_dfa(e); 759 if (IS_ERR(profile->file.dfa)) { 760 error = PTR_ERR(profile->file.dfa); 761 profile->file.dfa = NULL; 762 info = "failed to unpack profile file rules"; 763 goto fail; 764 } else if (profile->file.dfa) { 765 if (!unpack_u32(e, &profile->file.start, "dfa_start")) 766 /* default start state */ 767 profile->file.start = DFA_START; 768 } else if (profile->policy.dfa && 769 profile->policy.start[AA_CLASS_FILE]) { 770 profile->file.dfa = aa_get_dfa(profile->policy.dfa); 771 profile->file.start = profile->policy.start[AA_CLASS_FILE]; 772 } else 773 profile->file.dfa = aa_get_dfa(nulldfa); 774 775 if (!unpack_trans_table(e, profile)) { 776 info = "failed to unpack profile transition table"; 777 goto fail; 778 } 779 780 if (unpack_nameX(e, AA_STRUCT, "data")) { 781 info = "out of memory"; 782 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL); 783 if (!profile->data) 784 goto fail; 785 786 params.nelem_hint = 3; 787 params.key_len = sizeof(void *); 788 params.key_offset = offsetof(struct aa_data, key); 789 params.head_offset = offsetof(struct aa_data, head); 790 params.hashfn = strhash; 791 params.obj_cmpfn = datacmp; 792 793 if (rhashtable_init(profile->data, ¶ms)) { 794 info = "failed to init key, value hash table"; 795 goto fail; 796 } 797 798 while (unpack_strdup(e, &key, NULL)) { 799 data = kzalloc(sizeof(*data), GFP_KERNEL); 800 if (!data) { 801 kzfree(key); 802 goto fail; 803 } 804 805 data->key = key; 806 data->size = unpack_blob(e, &data->data, NULL); 807 data->data = kvmemdup(data->data, data->size); 808 if (data->size && !data->data) { 809 kzfree(data->key); 810 kzfree(data); 811 goto fail; 812 } 813 814 rhashtable_insert_fast(profile->data, &data->head, 815 profile->data->p); 816 } 817 818 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) { 819 info = "failed to unpack end of key, value data table"; 820 goto fail; 821 } 822 } 823 824 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) { 825 info = "failed to unpack end of profile"; 826 goto fail; 827 } 828 829 return profile; 830 831 fail: 832 if (profile) 833 name = NULL; 834 else if (!name) 835 name = "unknown"; 836 audit_iface(profile, NULL, name, info, e, error); 837 aa_free_profile(profile); 838 839 return ERR_PTR(error); 840 } 841 842 /** 843 * verify_head - unpack serialized stream header 844 * @e: serialized data read head (NOT NULL) 845 * @required: whether the header is required or optional 846 * @ns: Returns - namespace if one is specified else NULL (NOT NULL) 847 * 848 * Returns: error or 0 if header is good 849 */ 850 static int verify_header(struct aa_ext *e, int required, const char **ns) 851 { 852 int error = -EPROTONOSUPPORT; 853 const char *name = NULL; 854 *ns = NULL; 855 856 /* get the interface version */ 857 if (!unpack_u32(e, &e->version, "version")) { 858 if (required) { 859 audit_iface(NULL, NULL, NULL, "invalid profile format", 860 e, error); 861 return error; 862 } 863 } 864 865 /* Check that the interface version is currently supported. 866 * if not specified use previous version 867 * Mask off everything that is not kernel abi version 868 */ 869 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) { 870 audit_iface(NULL, NULL, NULL, "unsupported interface version", 871 e, error); 872 return error; 873 } 874 875 /* read the namespace if present */ 876 if (unpack_str(e, &name, "namespace")) { 877 if (*name == '\0') { 878 audit_iface(NULL, NULL, NULL, "invalid namespace name", 879 e, error); 880 return error; 881 } 882 if (*ns && strcmp(*ns, name)) 883 audit_iface(NULL, NULL, NULL, "invalid ns change", e, 884 error); 885 else if (!*ns) 886 *ns = name; 887 } 888 889 return 0; 890 } 891 892 static bool verify_xindex(int xindex, int table_size) 893 { 894 int index, xtype; 895 xtype = xindex & AA_X_TYPE_MASK; 896 index = xindex & AA_X_INDEX_MASK; 897 if (xtype == AA_X_TABLE && index >= table_size) 898 return 0; 899 return 1; 900 } 901 902 /* verify dfa xindexes are in range of transition tables */ 903 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size) 904 { 905 int i; 906 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) { 907 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size)) 908 return 0; 909 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size)) 910 return 0; 911 } 912 return 1; 913 } 914 915 /** 916 * verify_profile - Do post unpack analysis to verify profile consistency 917 * @profile: profile to verify (NOT NULL) 918 * 919 * Returns: 0 if passes verification else error 920 */ 921 static int verify_profile(struct aa_profile *profile) 922 { 923 if (profile->file.dfa && 924 !verify_dfa_xindex(profile->file.dfa, 925 profile->file.trans.size)) { 926 audit_iface(profile, NULL, NULL, "Invalid named transition", 927 NULL, -EPROTO); 928 return -EPROTO; 929 } 930 931 return 0; 932 } 933 934 void aa_load_ent_free(struct aa_load_ent *ent) 935 { 936 if (ent) { 937 aa_put_profile(ent->rename); 938 aa_put_profile(ent->old); 939 aa_put_profile(ent->new); 940 kfree(ent->ns_name); 941 kzfree(ent); 942 } 943 } 944 945 struct aa_load_ent *aa_load_ent_alloc(void) 946 { 947 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL); 948 if (ent) 949 INIT_LIST_HEAD(&ent->list); 950 return ent; 951 } 952 953 /** 954 * aa_unpack - unpack packed binary profile(s) data loaded from user space 955 * @udata: user data copied to kmem (NOT NULL) 956 * @lh: list to place unpacked profiles in a aa_repl_ws 957 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL) 958 * 959 * Unpack user data and return refcounted allocated profile(s) stored in 960 * @lh in order of discovery, with the list chain stored in base.list 961 * or error 962 * 963 * Returns: profile(s) on @lh else error pointer if fails to unpack 964 */ 965 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, 966 const char **ns) 967 { 968 struct aa_load_ent *tmp, *ent; 969 struct aa_profile *profile = NULL; 970 int error; 971 struct aa_ext e = { 972 .start = udata->data, 973 .end = udata->data + udata->size, 974 .pos = udata->data, 975 }; 976 977 *ns = NULL; 978 while (e.pos < e.end) { 979 char *ns_name = NULL; 980 void *start; 981 error = verify_header(&e, e.pos == e.start, ns); 982 if (error) 983 goto fail; 984 985 start = e.pos; 986 profile = unpack_profile(&e, &ns_name); 987 if (IS_ERR(profile)) { 988 error = PTR_ERR(profile); 989 goto fail; 990 } 991 992 error = verify_profile(profile); 993 if (error) 994 goto fail_profile; 995 996 if (aa_g_hash_policy) 997 error = aa_calc_profile_hash(profile, e.version, start, 998 e.pos - start); 999 if (error) 1000 goto fail_profile; 1001 1002 ent = aa_load_ent_alloc(); 1003 if (!ent) { 1004 error = -ENOMEM; 1005 goto fail_profile; 1006 } 1007 1008 ent->new = profile; 1009 ent->ns_name = ns_name; 1010 list_add_tail(&ent->list, lh); 1011 } 1012 udata->abi = e.version & K_ABI_MASK; 1013 if (aa_g_hash_policy) { 1014 udata->hash = aa_calc_hash(udata->data, udata->size); 1015 if (IS_ERR(udata->hash)) { 1016 error = PTR_ERR(udata->hash); 1017 udata->hash = NULL; 1018 goto fail; 1019 } 1020 } 1021 return 0; 1022 1023 fail_profile: 1024 aa_put_profile(profile); 1025 1026 fail: 1027 list_for_each_entry_safe(ent, tmp, lh, list) { 1028 list_del_init(&ent->list); 1029 aa_load_ent_free(ent); 1030 } 1031 1032 return error; 1033 } 1034