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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/*
33 * The AppArmor interface treats data as a type byte followed by the
34 * actual data. The interface has the notion of a a named entry
35 * which has a name (AA_NAME typecode followed by name string) followed by
36 * the entries typecode and data. Named types allow for optional
37 * elements and extensions to be added and tested for without breaking
38 * backwards compatibility.
39 */
40
41enum aa_code {
42 AA_U8,
43 AA_U16,
44 AA_U32,
45 AA_U64,
46 AA_NAME, /* same as string except it is items name */
47 AA_STRING,
48 AA_BLOB,
49 AA_STRUCT,
50 AA_STRUCTEND,
51 AA_LIST,
52 AA_LISTEND,
53 AA_ARRAY,
54 AA_ARRAYEND,
55};
56
57/*
58 * aa_ext is the read of the buffer containing the serialized profile. The
59 * data is copied into a kernel buffer in apparmorfs and then handed off to
60 * the unpack routines.
61 */
62struct aa_ext {
63 void *start;
64 void *end;
65 void *pos; /* pointer to current position in the buffer */
66 u32 version;
67};
68
69/* audit callback for unpack fields */
70static void audit_cb(struct audit_buffer *ab, void *va)
71{
72 struct common_audit_data *sa = va;
73 if (sa->aad->iface.target) {
74 struct aa_profile *name = sa->aad->iface.target;
75 audit_log_format(ab, " name=");
76 audit_log_untrustedstring(ab, name->base.hname);
77 }
78 if (sa->aad->iface.pos)
79 audit_log_format(ab, " offset=%ld", sa->aad->iface.pos);
80}
81
82/**
83 * audit_iface - do audit message for policy unpacking/load/replace/remove
84 * @new: profile if it has been allocated (MAYBE NULL)
85 * @name: name of the profile being manipulated (MAYBE NULL)
86 * @info: any extra info about the failure (MAYBE NULL)
87 * @e: buffer position info
88 * @error: error code
89 *
90 * Returns: %0 or error
91 */
92static int audit_iface(struct aa_profile *new, const char *name,
93 const char *info, struct aa_ext *e, int error)
94{
95 struct aa_profile *profile = __aa_current_profile();
96 struct common_audit_data sa;
97 struct apparmor_audit_data aad = {0,};
98 sa.type = LSM_AUDIT_DATA_NONE;
99 sa.aad = &aad;
100 if (e)
101 aad.iface.pos = e->pos - e->start;
102 aad.iface.target = new;
103 aad.name = name;
104 aad.info = info;
105 aad.error = error;
106
107 return aa_audit(AUDIT_APPARMOR_STATUS, profile, GFP_KERNEL, &sa,
108 audit_cb);
109}
110
111/* test if read will be in packed data bounds */
112static bool inbounds(struct aa_ext *e, size_t size)
113{
114 return (size <= e->end - e->pos);
115}
116
117/**
118 * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
119 * @e: serialized data read head (NOT NULL)
120 * @chunk: start address for chunk of data (NOT NULL)
121 *
122 * Returns: the size of chunk found with the read head at the end of the chunk.
123 */
124static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
125{
126 size_t size = 0;
127
128 if (!inbounds(e, sizeof(u16)))
129 return 0;
130 size = le16_to_cpu(get_unaligned((u16 *) e->pos));
131 e->pos += sizeof(u16);
132 if (!inbounds(e, size))
133 return 0;
134 *chunk = e->pos;
135 e->pos += size;
136 return size;
137}
138
139/* unpack control byte */
140static bool unpack_X(struct aa_ext *e, enum aa_code code)
141{
142 if (!inbounds(e, 1))
143 return 0;
144 if (*(u8 *) e->pos != code)
145 return 0;
146 e->pos++;
147 return 1;
148}
149
150/**
151 * unpack_nameX - check is the next element is of type X with a name of @name
152 * @e: serialized data extent information (NOT NULL)
153 * @code: type code
154 * @name: name to match to the serialized element. (MAYBE NULL)
155 *
156 * check that the next serialized data element is of type X and has a tag
157 * name @name. If @name is specified then there must be a matching
158 * name element in the stream. If @name is NULL any name element will be
159 * skipped and only the typecode will be tested.
160 *
161 * Returns 1 on success (both type code and name tests match) and the read
162 * head is advanced past the headers
163 *
164 * Returns: 0 if either match fails, the read head does not move
165 */
166static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
167{
168 /*
169 * May need to reset pos if name or type doesn't match
170 */
171 void *pos = e->pos;
172 /*
173 * Check for presence of a tagname, and if present name size
174 * AA_NAME tag value is a u16.
175 */
176 if (unpack_X(e, AA_NAME)) {
177 char *tag = NULL;
178 size_t size = unpack_u16_chunk(e, &tag);
179 /* if a name is specified it must match. otherwise skip tag */
180 if (name && (!size || strcmp(name, tag)))
181 goto fail;
182 } else if (name) {
183 /* if a name is specified and there is no name tag fail */
184 goto fail;
185 }
186
187 /* now check if type code matches */
188 if (unpack_X(e, code))
189 return 1;
190
191fail:
192 e->pos = pos;
193 return 0;
194}
195
196static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
197{
198 if (unpack_nameX(e, AA_U32, name)) {
199 if (!inbounds(e, sizeof(u32)))
200 return 0;
201 if (data)
202 *data = le32_to_cpu(get_unaligned((u32 *) e->pos));
203 e->pos += sizeof(u32);
204 return 1;
205 }
206 return 0;
207}
208
209static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
210{
211 if (unpack_nameX(e, AA_U64, name)) {
212 if (!inbounds(e, sizeof(u64)))
213 return 0;
214 if (data)
215 *data = le64_to_cpu(get_unaligned((u64 *) e->pos));
216 e->pos += sizeof(u64);
217 return 1;
218 }
219 return 0;
220}
221
222static size_t unpack_array(struct aa_ext *e, const char *name)
223{
224 if (unpack_nameX(e, AA_ARRAY, name)) {
225 int size;
226 if (!inbounds(e, sizeof(u16)))
227 return 0;
228 size = (int)le16_to_cpu(get_unaligned((u16 *) e->pos));
229 e->pos += sizeof(u16);
230 return size;
231 }
232 return 0;
233}
234
235static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
236{
237 if (unpack_nameX(e, AA_BLOB, name)) {
238 u32 size;
239 if (!inbounds(e, sizeof(u32)))
240 return 0;
241 size = le32_to_cpu(get_unaligned((u32 *) e->pos));
242 e->pos += sizeof(u32);
243 if (inbounds(e, (size_t) size)) {
244 *blob = e->pos;
245 e->pos += size;
246 return size;
247 }
248 }
249 return 0;
250}
251
252static int unpack_str(struct aa_ext *e, const char **string, const char *name)
253{
254 char *src_str;
255 size_t size = 0;
256 void *pos = e->pos;
257 *string = NULL;
258 if (unpack_nameX(e, AA_STRING, name)) {
259 size = unpack_u16_chunk(e, &src_str);
260 if (size) {
261 /* strings are null terminated, length is size - 1 */
262 if (src_str[size - 1] != 0)
263 goto fail;
264 *string = src_str;
265 }
266 }
267 return size;
268
269fail:
270 e->pos = pos;
271 return 0;
272}
273
274static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
275{
276 const char *tmp;
277 void *pos = e->pos;
278 int res = unpack_str(e, &tmp, name);
279 *string = NULL;
280
281 if (!res)
282 return 0;
283
284 *string = kmemdup(tmp, res, GFP_KERNEL);
285 if (!*string) {
286 e->pos = pos;
287 return 0;
288 }
289
290 return res;
291}
292
293#define DFA_VALID_PERM_MASK 0xffffffff
294#define DFA_VALID_PERM2_MASK 0xffffffff
295
296/**
297 * verify_accept - verify the accept tables of a dfa
298 * @dfa: dfa to verify accept tables of (NOT NULL)
299 * @flags: flags governing dfa
300 *
301 * Returns: 1 if valid accept tables else 0 if error
302 */
303static bool verify_accept(struct aa_dfa *dfa, int flags)
304{
305 int i;
306
307 /* verify accept permissions */
308 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
309 int mode = ACCEPT_TABLE(dfa)[i];
310
311 if (mode & ~DFA_VALID_PERM_MASK)
312 return 0;
313
314 if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
315 return 0;
316 }
317 return 1;
318}
319
320/**
321 * unpack_dfa - unpack a file rule dfa
322 * @e: serialized data extent information (NOT NULL)
323 *
324 * returns dfa or ERR_PTR or NULL if no dfa
325 */
326static struct aa_dfa *unpack_dfa(struct aa_ext *e)
327{
328 char *blob = NULL;
329 size_t size;
330 struct aa_dfa *dfa = NULL;
331
332 size = unpack_blob(e, &blob, "aadfa");
333 if (size) {
334 /*
335 * The dfa is aligned with in the blob to 8 bytes
336 * from the beginning of the stream.
337 * alignment adjust needed by dfa unpack
338 */
339 size_t sz = blob - (char *) e->start -
340 ((e->pos - e->start) & 7);
341 size_t pad = ALIGN(sz, 8) - sz;
342 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
343 TO_ACCEPT2_FLAG(YYTD_DATA32);
344
345
346 if (aa_g_paranoid_load)
347 flags |= DFA_FLAG_VERIFY_STATES;
348
349 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
350
351 if (IS_ERR(dfa))
352 return dfa;
353
354 if (!verify_accept(dfa, flags))
355 goto fail;
356 }
357
358 return dfa;
359
360fail:
361 aa_put_dfa(dfa);
362 return ERR_PTR(-EPROTO);
363}
364
365/**
366 * unpack_trans_table - unpack a profile transition table
367 * @e: serialized data extent information (NOT NULL)
368 * @profile: profile to add the accept table to (NOT NULL)
369 *
370 * Returns: 1 if table successfully unpacked
371 */
372static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
373{
374 void *pos = e->pos;
375
376 /* exec table is optional */
377 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
378 int i, size;
379
380 size = unpack_array(e, NULL);
381 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
382 if (size > 16 - 4)
383 goto fail;
384 profile->file.trans.table = kzalloc(sizeof(char *) * size,
385 GFP_KERNEL);
386 if (!profile->file.trans.table)
387 goto fail;
388
389 profile->file.trans.size = size;
390 for (i = 0; i < size; i++) {
391 char *str;
392 int c, j, size2 = unpack_strdup(e, &str, NULL);
393 /* unpack_strdup verifies that the last character is
394 * null termination byte.
395 */
396 if (!size2)
397 goto fail;
398 profile->file.trans.table[i] = str;
399 /* verify that name doesn't start with space */
400 if (isspace(*str))
401 goto fail;
402
403 /* count internal # of internal \0 */
404 for (c = j = 0; j < size2 - 2; j++) {
405 if (!str[j])
406 c++;
407 }
408 if (*str == ':') {
409 /* beginning with : requires an embedded \0,
410 * verify that exactly 1 internal \0 exists
411 * trailing \0 already verified by unpack_strdup
412 */
413 if (c != 1)
414 goto fail;
415 /* first character after : must be valid */
416 if (!str[1])
417 goto fail;
418 } else if (c)
419 /* fail - all other cases with embedded \0 */
420 goto fail;
421 }
422 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
423 goto fail;
424 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
425 goto fail;
426 }
427 return 1;
428
429fail:
430 aa_free_domain_entries(&profile->file.trans);
431 e->pos = pos;
432 return 0;
433}
434
435static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
436{
437 void *pos = e->pos;
438
439 /* rlimits are optional */
440 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
441 int i, size;
442 u32 tmp = 0;
443 if (!unpack_u32(e, &tmp, NULL))
444 goto fail;
445 profile->rlimits.mask = tmp;
446
447 size = unpack_array(e, NULL);
448 if (size > RLIM_NLIMITS)
449 goto fail;
450 for (i = 0; i < size; i++) {
451 u64 tmp2 = 0;
452 int a = aa_map_resource(i);
453 if (!unpack_u64(e, &tmp2, NULL))
454 goto fail;
455 profile->rlimits.limits[a].rlim_max = tmp2;
456 }
457 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
458 goto fail;
459 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
460 goto fail;
461 }
462 return 1;
463
464fail:
465 e->pos = pos;
466 return 0;
467}
468
469/**
470 * unpack_profile - unpack a serialized profile
471 * @e: serialized data extent information (NOT NULL)
472 *
473 * NOTE: unpack profile sets audit struct if there is a failure
474 */
475static struct aa_profile *unpack_profile(struct aa_ext *e)
476{
477 struct aa_profile *profile = NULL;
478 const char *name = NULL;
479 int i, error = -EPROTO;
480 kernel_cap_t tmpcap;
481 u32 tmp;
482
483 /* check that we have the right struct being passed */
484 if (!unpack_nameX(e, AA_STRUCT, "profile"))
485 goto fail;
486 if (!unpack_str(e, &name, NULL))
487 goto fail;
488
489 profile = aa_alloc_profile(name);
490 if (!profile)
491 return ERR_PTR(-ENOMEM);
492
493 /* profile renaming is optional */
494 (void) unpack_str(e, &profile->rename, "rename");
495
496 /* attachment string is optional */
497 (void) unpack_str(e, &profile->attach, "attach");
498
499 /* xmatch is optional and may be NULL */
500 profile->xmatch = unpack_dfa(e);
501 if (IS_ERR(profile->xmatch)) {
502 error = PTR_ERR(profile->xmatch);
503 profile->xmatch = NULL;
504 goto fail;
505 }
506 /* xmatch_len is not optional if xmatch is set */
507 if (profile->xmatch) {
508 if (!unpack_u32(e, &tmp, NULL))
509 goto fail;
510 profile->xmatch_len = tmp;
511 }
512
513 /* per profile debug flags (complain, audit) */
514 if (!unpack_nameX(e, AA_STRUCT, "flags"))
515 goto fail;
516 if (!unpack_u32(e, &tmp, NULL))
517 goto fail;
518 if (tmp & PACKED_FLAG_HAT)
519 profile->flags |= PFLAG_HAT;
520 if (!unpack_u32(e, &tmp, NULL))
521 goto fail;
522 if (tmp == PACKED_MODE_COMPLAIN)
523 profile->mode = APPARMOR_COMPLAIN;
524 else if (tmp == PACKED_MODE_KILL)
525 profile->mode = APPARMOR_KILL;
526 else if (tmp == PACKED_MODE_UNCONFINED)
527 profile->mode = APPARMOR_UNCONFINED;
528 if (!unpack_u32(e, &tmp, NULL))
529 goto fail;
530 if (tmp)
531 profile->audit = AUDIT_ALL;
532
533 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
534 goto fail;
535
536 /* path_flags is optional */
537 if (unpack_u32(e, &profile->path_flags, "path_flags"))
538 profile->path_flags |= profile->flags & PFLAG_MEDIATE_DELETED;
539 else
540 /* set a default value if path_flags field is not present */
541 profile->path_flags = PFLAG_MEDIATE_DELETED;
542
543 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
544 goto fail;
545 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
546 goto fail;
547 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
548 goto fail;
549 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
550 goto fail;
551
552 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
553 /* optional upper half of 64 bit caps */
554 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
555 goto fail;
556 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
557 goto fail;
558 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
559 goto fail;
560 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
561 goto fail;
562 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
563 goto fail;
564 }
565
566 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
567 /* optional extended caps mediation mask */
568 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
569 goto fail;
570 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
571 goto fail;
572 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
573 goto fail;
574 }
575
576 if (!unpack_rlimits(e, profile))
577 goto fail;
578
579 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
580 /* generic policy dfa - optional and may be NULL */
581 profile->policy.dfa = unpack_dfa(e);
582 if (IS_ERR(profile->policy.dfa)) {
583 error = PTR_ERR(profile->policy.dfa);
584 profile->policy.dfa = NULL;
585 goto fail;
586 }
587 if (!unpack_u32(e, &profile->policy.start[0], "start"))
588 /* default start state */
589 profile->policy.start[0] = DFA_START;
590 /* setup class index */
591 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
592 profile->policy.start[i] =
593 aa_dfa_next(profile->policy.dfa,
594 profile->policy.start[0],
595 i);
596 }
597 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
598 goto fail;
599 }
600
601 /* get file rules */
602 profile->file.dfa = unpack_dfa(e);
603 if (IS_ERR(profile->file.dfa)) {
604 error = PTR_ERR(profile->file.dfa);
605 profile->file.dfa = NULL;
606 goto fail;
607 }
608
609 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
610 /* default start state */
611 profile->file.start = DFA_START;
612
613 if (!unpack_trans_table(e, profile))
614 goto fail;
615
616 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
617 goto fail;
618
619 return profile;
620
621fail:
622 if (profile)
623 name = NULL;
624 else if (!name)
625 name = "unknown";
626 audit_iface(profile, name, "failed to unpack profile", e, error);
627 aa_free_profile(profile);
628
629 return ERR_PTR(error);
630}
631
632/**
633 * verify_head - unpack serialized stream header
634 * @e: serialized data read head (NOT NULL)
635 * @required: whether the header is required or optional
636 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
637 *
638 * Returns: error or 0 if header is good
639 */
640static int verify_header(struct aa_ext *e, int required, const char **ns)
641{
642 int error = -EPROTONOSUPPORT;
643 const char *name = NULL;
644 *ns = NULL;
645
646 /* get the interface version */
647 if (!unpack_u32(e, &e->version, "version")) {
648 if (required) {
649 audit_iface(NULL, NULL, "invalid profile format", e,
650 error);
651 return error;
652 }
653
654 /* check that the interface version is currently supported */
655 if (e->version != 5) {
656 audit_iface(NULL, NULL, "unsupported interface version",
657 e, error);
658 return error;
659 }
660 }
661
662
663 /* read the namespace if present */
664 if (unpack_str(e, &name, "namespace")) {
665 if (*ns && strcmp(*ns, name))
666 audit_iface(NULL, NULL, "invalid ns change", e, error);
667 else if (!*ns)
668 *ns = name;
669 }
670
671 return 0;
672}
673
674static bool verify_xindex(int xindex, int table_size)
675{
676 int index, xtype;
677 xtype = xindex & AA_X_TYPE_MASK;
678 index = xindex & AA_X_INDEX_MASK;
679 if (xtype == AA_X_TABLE && index > table_size)
680 return 0;
681 return 1;
682}
683
684/* verify dfa xindexes are in range of transition tables */
685static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
686{
687 int i;
688 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
689 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
690 return 0;
691 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
692 return 0;
693 }
694 return 1;
695}
696
697/**
698 * verify_profile - Do post unpack analysis to verify profile consistency
699 * @profile: profile to verify (NOT NULL)
700 *
701 * Returns: 0 if passes verification else error
702 */
703static int verify_profile(struct aa_profile *profile)
704{
705 if (aa_g_paranoid_load) {
706 if (profile->file.dfa &&
707 !verify_dfa_xindex(profile->file.dfa,
708 profile->file.trans.size)) {
709 audit_iface(profile, NULL, "Invalid named transition",
710 NULL, -EPROTO);
711 return -EPROTO;
712 }
713 }
714
715 return 0;
716}
717
718void aa_load_ent_free(struct aa_load_ent *ent)
719{
720 if (ent) {
721 aa_put_profile(ent->rename);
722 aa_put_profile(ent->old);
723 aa_put_profile(ent->new);
724 kzfree(ent);
725 }
726}
727
728struct aa_load_ent *aa_load_ent_alloc(void)
729{
730 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
731 if (ent)
732 INIT_LIST_HEAD(&ent->list);
733 return ent;
734}
735
736/**
737 * aa_unpack - unpack packed binary profile(s) data loaded from user space
738 * @udata: user data copied to kmem (NOT NULL)
739 * @size: the size of the user data
740 * @lh: list to place unpacked profiles in a aa_repl_ws
741 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
742 *
743 * Unpack user data and return refcounted allocated profile(s) stored in
744 * @lh in order of discovery, with the list chain stored in base.list
745 * or error
746 *
747 * Returns: profile(s) on @lh else error pointer if fails to unpack
748 */
749int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns)
750{
751 struct aa_load_ent *tmp, *ent;
752 struct aa_profile *profile = NULL;
753 int error;
754 struct aa_ext e = {
755 .start = udata,
756 .end = udata + size,
757 .pos = udata,
758 };
759
760 *ns = NULL;
761 while (e.pos < e.end) {
762 void *start;
763 error = verify_header(&e, e.pos == e.start, ns);
764 if (error)
765 goto fail;
766
767 start = e.pos;
768 profile = unpack_profile(&e);
769 if (IS_ERR(profile)) {
770 error = PTR_ERR(profile);
771 goto fail;
772 }
773
774 error = verify_profile(profile);
775 if (error)
776 goto fail_profile;
777
778 error = aa_calc_profile_hash(profile, e.version, start,
779 e.pos - start);
780 if (error)
781 goto fail_profile;
782
783 ent = aa_load_ent_alloc();
784 if (!ent) {
785 error = -ENOMEM;
786 goto fail_profile;
787 }
788
789 ent->new = profile;
790 list_add_tail(&ent->list, lh);
791 }
792
793 return 0;
794
795fail_profile:
796 aa_put_profile(profile);
797
798fail:
799 list_for_each_entry_safe(ent, tmp, lh, list) {
800 list_del_init(&ent->list);
801 aa_load_ent_free(ent);
802 }
803
804 return error;
805}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor functions for unpacking policy loaded from
6 * userspace.
7 *
8 * Copyright (C) 1998-2008 Novell/SUSE
9 * Copyright 2009-2010 Canonical Ltd.
10 *
11 * AppArmor uses a serialized binary format for loading policy. To find
12 * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst
13 * All policy is validated before it is used.
14 */
15
16#include <asm/unaligned.h>
17#include <kunit/visibility.h>
18#include <linux/ctype.h>
19#include <linux/errno.h>
20#include <linux/zstd.h>
21
22#include "include/apparmor.h"
23#include "include/audit.h"
24#include "include/cred.h"
25#include "include/crypto.h"
26#include "include/file.h"
27#include "include/match.h"
28#include "include/path.h"
29#include "include/policy.h"
30#include "include/policy_unpack.h"
31#include "include/policy_compat.h"
32
33/* audit callback for unpack fields */
34static void audit_cb(struct audit_buffer *ab, void *va)
35{
36 struct common_audit_data *sa = va;
37
38 if (aad(sa)->iface.ns) {
39 audit_log_format(ab, " ns=");
40 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
41 }
42 if (aad(sa)->name) {
43 audit_log_format(ab, " name=");
44 audit_log_untrustedstring(ab, aad(sa)->name);
45 }
46 if (aad(sa)->iface.pos)
47 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
48}
49
50/**
51 * audit_iface - do audit message for policy unpacking/load/replace/remove
52 * @new: profile if it has been allocated (MAYBE NULL)
53 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
54 * @name: name of the profile being manipulated (MAYBE NULL)
55 * @info: any extra info about the failure (MAYBE NULL)
56 * @e: buffer position info
57 * @error: error code
58 *
59 * Returns: %0 or error
60 */
61static int audit_iface(struct aa_profile *new, const char *ns_name,
62 const char *name, const char *info, struct aa_ext *e,
63 int error)
64{
65 struct aa_profile *profile = labels_profile(aa_current_raw_label());
66 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL);
67 if (e)
68 aad(&sa)->iface.pos = e->pos - e->start;
69 aad(&sa)->iface.ns = ns_name;
70 if (new)
71 aad(&sa)->name = new->base.hname;
72 else
73 aad(&sa)->name = name;
74 aad(&sa)->info = info;
75 aad(&sa)->error = error;
76
77 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
78}
79
80void __aa_loaddata_update(struct aa_loaddata *data, long revision)
81{
82 AA_BUG(!data);
83 AA_BUG(!data->ns);
84 AA_BUG(!mutex_is_locked(&data->ns->lock));
85 AA_BUG(data->revision > revision);
86
87 data->revision = revision;
88 if ((data->dents[AAFS_LOADDATA_REVISION])) {
89 d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
90 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
91 d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
92 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
93 }
94}
95
96bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
97{
98 if (l->size != r->size)
99 return false;
100 if (l->compressed_size != r->compressed_size)
101 return false;
102 if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
103 return false;
104 return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0;
105}
106
107/*
108 * need to take the ns mutex lock which is NOT safe most places that
109 * put_loaddata is called, so we have to delay freeing it
110 */
111static void do_loaddata_free(struct work_struct *work)
112{
113 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
114 struct aa_ns *ns = aa_get_ns(d->ns);
115
116 if (ns) {
117 mutex_lock_nested(&ns->lock, ns->level);
118 __aa_fs_remove_rawdata(d);
119 mutex_unlock(&ns->lock);
120 aa_put_ns(ns);
121 }
122
123 kfree_sensitive(d->hash);
124 kfree_sensitive(d->name);
125 kvfree(d->data);
126 kfree_sensitive(d);
127}
128
129void aa_loaddata_kref(struct kref *kref)
130{
131 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
132
133 if (d) {
134 INIT_WORK(&d->work, do_loaddata_free);
135 schedule_work(&d->work);
136 }
137}
138
139struct aa_loaddata *aa_loaddata_alloc(size_t size)
140{
141 struct aa_loaddata *d;
142
143 d = kzalloc(sizeof(*d), GFP_KERNEL);
144 if (d == NULL)
145 return ERR_PTR(-ENOMEM);
146 d->data = kvzalloc(size, GFP_KERNEL);
147 if (!d->data) {
148 kfree(d);
149 return ERR_PTR(-ENOMEM);
150 }
151 kref_init(&d->count);
152 INIT_LIST_HEAD(&d->list);
153
154 return d;
155}
156
157/* test if read will be in packed data bounds */
158VISIBLE_IF_KUNIT bool aa_inbounds(struct aa_ext *e, size_t size)
159{
160 return (size <= e->end - e->pos);
161}
162EXPORT_SYMBOL_IF_KUNIT(aa_inbounds);
163
164static void *kvmemdup(const void *src, size_t len)
165{
166 void *p = kvmalloc(len, GFP_KERNEL);
167
168 if (p)
169 memcpy(p, src, len);
170 return p;
171}
172
173/**
174 * aa_unpack_u16_chunk - test and do bounds checking for a u16 size based chunk
175 * @e: serialized data read head (NOT NULL)
176 * @chunk: start address for chunk of data (NOT NULL)
177 *
178 * Returns: the size of chunk found with the read head at the end of the chunk.
179 */
180VISIBLE_IF_KUNIT size_t aa_unpack_u16_chunk(struct aa_ext *e, char **chunk)
181{
182 size_t size = 0;
183 void *pos = e->pos;
184
185 if (!aa_inbounds(e, sizeof(u16)))
186 goto fail;
187 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
188 e->pos += sizeof(__le16);
189 if (!aa_inbounds(e, size))
190 goto fail;
191 *chunk = e->pos;
192 e->pos += size;
193 return size;
194
195fail:
196 e->pos = pos;
197 return 0;
198}
199EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u16_chunk);
200
201/* unpack control byte */
202VISIBLE_IF_KUNIT bool aa_unpack_X(struct aa_ext *e, enum aa_code code)
203{
204 if (!aa_inbounds(e, 1))
205 return false;
206 if (*(u8 *) e->pos != code)
207 return false;
208 e->pos++;
209 return true;
210}
211EXPORT_SYMBOL_IF_KUNIT(aa_unpack_X);
212
213/**
214 * aa_unpack_nameX - check is the next element is of type X with a name of @name
215 * @e: serialized data extent information (NOT NULL)
216 * @code: type code
217 * @name: name to match to the serialized element. (MAYBE NULL)
218 *
219 * check that the next serialized data element is of type X and has a tag
220 * name @name. If @name is specified then there must be a matching
221 * name element in the stream. If @name is NULL any name element will be
222 * skipped and only the typecode will be tested.
223 *
224 * Returns true on success (both type code and name tests match) and the read
225 * head is advanced past the headers
226 *
227 * Returns: false if either match fails, the read head does not move
228 */
229VISIBLE_IF_KUNIT bool aa_unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
230{
231 /*
232 * May need to reset pos if name or type doesn't match
233 */
234 void *pos = e->pos;
235 /*
236 * Check for presence of a tagname, and if present name size
237 * AA_NAME tag value is a u16.
238 */
239 if (aa_unpack_X(e, AA_NAME)) {
240 char *tag = NULL;
241 size_t size = aa_unpack_u16_chunk(e, &tag);
242 /* if a name is specified it must match. otherwise skip tag */
243 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
244 goto fail;
245 } else if (name) {
246 /* if a name is specified and there is no name tag fail */
247 goto fail;
248 }
249
250 /* now check if type code matches */
251 if (aa_unpack_X(e, code))
252 return true;
253
254fail:
255 e->pos = pos;
256 return false;
257}
258EXPORT_SYMBOL_IF_KUNIT(aa_unpack_nameX);
259
260static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
261{
262 void *pos = e->pos;
263
264 if (aa_unpack_nameX(e, AA_U8, name)) {
265 if (!aa_inbounds(e, sizeof(u8)))
266 goto fail;
267 if (data)
268 *data = *((u8 *)e->pos);
269 e->pos += sizeof(u8);
270 return true;
271 }
272
273fail:
274 e->pos = pos;
275 return false;
276}
277
278VISIBLE_IF_KUNIT bool aa_unpack_u32(struct aa_ext *e, u32 *data, const char *name)
279{
280 void *pos = e->pos;
281
282 if (aa_unpack_nameX(e, AA_U32, name)) {
283 if (!aa_inbounds(e, sizeof(u32)))
284 goto fail;
285 if (data)
286 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
287 e->pos += sizeof(u32);
288 return true;
289 }
290
291fail:
292 e->pos = pos;
293 return false;
294}
295EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u32);
296
297VISIBLE_IF_KUNIT bool aa_unpack_u64(struct aa_ext *e, u64 *data, const char *name)
298{
299 void *pos = e->pos;
300
301 if (aa_unpack_nameX(e, AA_U64, name)) {
302 if (!aa_inbounds(e, sizeof(u64)))
303 goto fail;
304 if (data)
305 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
306 e->pos += sizeof(u64);
307 return true;
308 }
309
310fail:
311 e->pos = pos;
312 return false;
313}
314EXPORT_SYMBOL_IF_KUNIT(aa_unpack_u64);
315
316VISIBLE_IF_KUNIT bool aa_unpack_array(struct aa_ext *e, const char *name, u16 *size)
317{
318 void *pos = e->pos;
319
320 if (aa_unpack_nameX(e, AA_ARRAY, name)) {
321 if (!aa_inbounds(e, sizeof(u16)))
322 goto fail;
323 *size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
324 e->pos += sizeof(u16);
325 return true;
326 }
327
328fail:
329 e->pos = pos;
330 return false;
331}
332EXPORT_SYMBOL_IF_KUNIT(aa_unpack_array);
333
334VISIBLE_IF_KUNIT size_t aa_unpack_blob(struct aa_ext *e, char **blob, const char *name)
335{
336 void *pos = e->pos;
337
338 if (aa_unpack_nameX(e, AA_BLOB, name)) {
339 u32 size;
340 if (!aa_inbounds(e, sizeof(u32)))
341 goto fail;
342 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
343 e->pos += sizeof(u32);
344 if (aa_inbounds(e, (size_t) size)) {
345 *blob = e->pos;
346 e->pos += size;
347 return size;
348 }
349 }
350
351fail:
352 e->pos = pos;
353 return 0;
354}
355EXPORT_SYMBOL_IF_KUNIT(aa_unpack_blob);
356
357VISIBLE_IF_KUNIT int aa_unpack_str(struct aa_ext *e, const char **string, const char *name)
358{
359 char *src_str;
360 size_t size = 0;
361 void *pos = e->pos;
362 *string = NULL;
363 if (aa_unpack_nameX(e, AA_STRING, name)) {
364 size = aa_unpack_u16_chunk(e, &src_str);
365 if (size) {
366 /* strings are null terminated, length is size - 1 */
367 if (src_str[size - 1] != 0)
368 goto fail;
369 *string = src_str;
370
371 return size;
372 }
373 }
374
375fail:
376 e->pos = pos;
377 return 0;
378}
379EXPORT_SYMBOL_IF_KUNIT(aa_unpack_str);
380
381VISIBLE_IF_KUNIT int aa_unpack_strdup(struct aa_ext *e, char **string, const char *name)
382{
383 const char *tmp;
384 void *pos = e->pos;
385 int res = aa_unpack_str(e, &tmp, name);
386 *string = NULL;
387
388 if (!res)
389 return 0;
390
391 *string = kmemdup(tmp, res, GFP_KERNEL);
392 if (!*string) {
393 e->pos = pos;
394 return 0;
395 }
396
397 return res;
398}
399EXPORT_SYMBOL_IF_KUNIT(aa_unpack_strdup);
400
401
402/**
403 * unpack_dfa - unpack a file rule dfa
404 * @e: serialized data extent information (NOT NULL)
405 * @flags: dfa flags to check
406 *
407 * returns dfa or ERR_PTR or NULL if no dfa
408 */
409static struct aa_dfa *unpack_dfa(struct aa_ext *e, int flags)
410{
411 char *blob = NULL;
412 size_t size;
413 struct aa_dfa *dfa = NULL;
414
415 size = aa_unpack_blob(e, &blob, "aadfa");
416 if (size) {
417 /*
418 * The dfa is aligned with in the blob to 8 bytes
419 * from the beginning of the stream.
420 * alignment adjust needed by dfa unpack
421 */
422 size_t sz = blob - (char *) e->start -
423 ((e->pos - e->start) & 7);
424 size_t pad = ALIGN(sz, 8) - sz;
425 if (aa_g_paranoid_load)
426 flags |= DFA_FLAG_VERIFY_STATES;
427 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
428
429 if (IS_ERR(dfa))
430 return dfa;
431
432 }
433
434 return dfa;
435}
436
437/**
438 * unpack_trans_table - unpack a profile transition table
439 * @e: serialized data extent information (NOT NULL)
440 * @table: str table to unpack to (NOT NULL)
441 *
442 * Returns: true if table successfully unpacked or not present
443 */
444static bool unpack_trans_table(struct aa_ext *e, struct aa_str_table *strs)
445{
446 void *saved_pos = e->pos;
447 char **table = NULL;
448
449 /* exec table is optional */
450 if (aa_unpack_nameX(e, AA_STRUCT, "xtable")) {
451 u16 size;
452 int i;
453
454 if (!aa_unpack_array(e, NULL, &size))
455 /*
456 * Note: index into trans table array is a max
457 * of 2^24, but unpack array can only unpack
458 * an array of 2^16 in size atm so no need
459 * for size check here
460 */
461 goto fail;
462 table = kcalloc(size, sizeof(char *), GFP_KERNEL);
463 if (!table)
464 goto fail;
465
466 for (i = 0; i < size; i++) {
467 char *str;
468 int c, j, pos, size2 = aa_unpack_strdup(e, &str, NULL);
469 /* aa_unpack_strdup verifies that the last character is
470 * null termination byte.
471 */
472 if (!size2)
473 goto fail;
474 table[i] = str;
475 /* verify that name doesn't start with space */
476 if (isspace(*str))
477 goto fail;
478
479 /* count internal # of internal \0 */
480 for (c = j = 0; j < size2 - 1; j++) {
481 if (!str[j]) {
482 pos = j;
483 c++;
484 }
485 }
486 if (*str == ':') {
487 /* first character after : must be valid */
488 if (!str[1])
489 goto fail;
490 /* beginning with : requires an embedded \0,
491 * verify that exactly 1 internal \0 exists
492 * trailing \0 already verified by aa_unpack_strdup
493 *
494 * convert \0 back to : for label_parse
495 */
496 if (c == 1)
497 str[pos] = ':';
498 else if (c > 1)
499 goto fail;
500 } else if (c)
501 /* fail - all other cases with embedded \0 */
502 goto fail;
503 }
504 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL))
505 goto fail;
506 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
507 goto fail;
508
509 strs->table = table;
510 strs->size = size;
511 }
512 return true;
513
514fail:
515 kfree_sensitive(table);
516 e->pos = saved_pos;
517 return false;
518}
519
520static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
521{
522 void *pos = e->pos;
523
524 if (aa_unpack_nameX(e, AA_STRUCT, "xattrs")) {
525 u16 size;
526 int i;
527
528 if (!aa_unpack_array(e, NULL, &size))
529 goto fail;
530 profile->attach.xattr_count = size;
531 profile->attach.xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
532 if (!profile->attach.xattrs)
533 goto fail;
534 for (i = 0; i < size; i++) {
535 if (!aa_unpack_strdup(e, &profile->attach.xattrs[i], NULL))
536 goto fail;
537 }
538 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL))
539 goto fail;
540 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
541 goto fail;
542 }
543
544 return true;
545
546fail:
547 e->pos = pos;
548 return false;
549}
550
551static bool unpack_secmark(struct aa_ext *e, struct aa_ruleset *rules)
552{
553 void *pos = e->pos;
554 u16 size;
555 int i;
556
557 if (aa_unpack_nameX(e, AA_STRUCT, "secmark")) {
558 if (!aa_unpack_array(e, NULL, &size))
559 goto fail;
560
561 rules->secmark = kcalloc(size, sizeof(struct aa_secmark),
562 GFP_KERNEL);
563 if (!rules->secmark)
564 goto fail;
565
566 rules->secmark_count = size;
567
568 for (i = 0; i < size; i++) {
569 if (!unpack_u8(e, &rules->secmark[i].audit, NULL))
570 goto fail;
571 if (!unpack_u8(e, &rules->secmark[i].deny, NULL))
572 goto fail;
573 if (!aa_unpack_strdup(e, &rules->secmark[i].label, NULL))
574 goto fail;
575 }
576 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL))
577 goto fail;
578 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
579 goto fail;
580 }
581
582 return true;
583
584fail:
585 if (rules->secmark) {
586 for (i = 0; i < size; i++)
587 kfree(rules->secmark[i].label);
588 kfree(rules->secmark);
589 rules->secmark_count = 0;
590 rules->secmark = NULL;
591 }
592
593 e->pos = pos;
594 return false;
595}
596
597static bool unpack_rlimits(struct aa_ext *e, struct aa_ruleset *rules)
598{
599 void *pos = e->pos;
600
601 /* rlimits are optional */
602 if (aa_unpack_nameX(e, AA_STRUCT, "rlimits")) {
603 u16 size;
604 int i;
605 u32 tmp = 0;
606 if (!aa_unpack_u32(e, &tmp, NULL))
607 goto fail;
608 rules->rlimits.mask = tmp;
609
610 if (!aa_unpack_array(e, NULL, &size) ||
611 size > RLIM_NLIMITS)
612 goto fail;
613 for (i = 0; i < size; i++) {
614 u64 tmp2 = 0;
615 int a = aa_map_resource(i);
616 if (!aa_unpack_u64(e, &tmp2, NULL))
617 goto fail;
618 rules->rlimits.limits[a].rlim_max = tmp2;
619 }
620 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL))
621 goto fail;
622 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
623 goto fail;
624 }
625 return true;
626
627fail:
628 e->pos = pos;
629 return false;
630}
631
632static bool unpack_perm(struct aa_ext *e, u32 version, struct aa_perms *perm)
633{
634 if (version != 1)
635 return false;
636
637 return aa_unpack_u32(e, &perm->allow, NULL) &&
638 aa_unpack_u32(e, &perm->allow, NULL) &&
639 aa_unpack_u32(e, &perm->deny, NULL) &&
640 aa_unpack_u32(e, &perm->subtree, NULL) &&
641 aa_unpack_u32(e, &perm->cond, NULL) &&
642 aa_unpack_u32(e, &perm->kill, NULL) &&
643 aa_unpack_u32(e, &perm->complain, NULL) &&
644 aa_unpack_u32(e, &perm->prompt, NULL) &&
645 aa_unpack_u32(e, &perm->audit, NULL) &&
646 aa_unpack_u32(e, &perm->quiet, NULL) &&
647 aa_unpack_u32(e, &perm->hide, NULL) &&
648 aa_unpack_u32(e, &perm->xindex, NULL) &&
649 aa_unpack_u32(e, &perm->tag, NULL) &&
650 aa_unpack_u32(e, &perm->label, NULL);
651}
652
653static ssize_t unpack_perms_table(struct aa_ext *e, struct aa_perms **perms)
654{
655 void *pos = e->pos;
656 u16 size = 0;
657
658 AA_BUG(!perms);
659 /*
660 * policy perms are optional, in which case perms are embedded
661 * in the dfa accept table
662 */
663 if (aa_unpack_nameX(e, AA_STRUCT, "perms")) {
664 int i;
665 u32 version;
666
667 if (!aa_unpack_u32(e, &version, "version"))
668 goto fail_reset;
669 if (!aa_unpack_array(e, NULL, &size))
670 goto fail_reset;
671 *perms = kcalloc(size, sizeof(struct aa_perms), GFP_KERNEL);
672 if (!*perms)
673 goto fail_reset;
674 for (i = 0; i < size; i++) {
675 if (!unpack_perm(e, version, &(*perms)[i]))
676 goto fail;
677 }
678 if (!aa_unpack_nameX(e, AA_ARRAYEND, NULL))
679 goto fail;
680 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
681 goto fail;
682 } else
683 *perms = NULL;
684
685 return size;
686
687fail:
688 kfree(*perms);
689fail_reset:
690 e->pos = pos;
691 return -EPROTO;
692}
693
694static int unpack_pdb(struct aa_ext *e, struct aa_policydb *policy,
695 bool required_dfa, bool required_trans,
696 const char **info)
697{
698 void *pos = e->pos;
699 int i, flags, error = -EPROTO;
700 ssize_t size;
701
702 size = unpack_perms_table(e, &policy->perms);
703 if (size < 0) {
704 error = size;
705 policy->perms = NULL;
706 *info = "failed to unpack - perms";
707 goto fail;
708 }
709 policy->size = size;
710
711 if (policy->perms) {
712 /* perms table present accept is index */
713 flags = TO_ACCEPT1_FLAG(YYTD_DATA32);
714 } else {
715 /* packed perms in accept1 and accept2 */
716 flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
717 TO_ACCEPT2_FLAG(YYTD_DATA32);
718 }
719
720 policy->dfa = unpack_dfa(e, flags);
721 if (IS_ERR(policy->dfa)) {
722 error = PTR_ERR(policy->dfa);
723 policy->dfa = NULL;
724 *info = "failed to unpack - dfa";
725 goto fail;
726 } else if (!policy->dfa) {
727 if (required_dfa) {
728 *info = "missing required dfa";
729 goto fail;
730 }
731 goto out;
732 }
733
734 /*
735 * only unpack the following if a dfa is present
736 *
737 * sadly start was given different names for file and policydb
738 * but since it is optional we can try both
739 */
740 if (!aa_unpack_u32(e, &policy->start[0], "start"))
741 /* default start state */
742 policy->start[0] = DFA_START;
743 if (!aa_unpack_u32(e, &policy->start[AA_CLASS_FILE], "dfa_start")) {
744 /* default start state for xmatch and file dfa */
745 policy->start[AA_CLASS_FILE] = DFA_START;
746 } /* setup class index */
747 for (i = AA_CLASS_FILE + 1; i <= AA_CLASS_LAST; i++) {
748 policy->start[i] = aa_dfa_next(policy->dfa, policy->start[0],
749 i);
750 }
751 if (!unpack_trans_table(e, &policy->trans) && required_trans) {
752 *info = "failed to unpack profile transition table";
753 goto fail;
754 }
755
756 /* TODO: move compat mapping here, requires dfa merging first */
757 /* TODO: move verify here, it has to be done after compat mappings */
758out:
759 return 0;
760
761fail:
762 e->pos = pos;
763 return error;
764}
765
766static u32 strhash(const void *data, u32 len, u32 seed)
767{
768 const char * const *key = data;
769
770 return jhash(*key, strlen(*key), seed);
771}
772
773static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
774{
775 const struct aa_data *data = obj;
776 const char * const *key = arg->key;
777
778 return strcmp(data->key, *key);
779}
780
781/**
782 * unpack_profile - unpack a serialized profile
783 * @e: serialized data extent information (NOT NULL)
784 * @ns_name: pointer of newly allocated copy of %NULL in case of error
785 *
786 * NOTE: unpack profile sets audit struct if there is a failure
787 */
788static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
789{
790 struct aa_ruleset *rules;
791 struct aa_profile *profile = NULL;
792 const char *tmpname, *tmpns = NULL, *name = NULL;
793 const char *info = "failed to unpack profile";
794 size_t ns_len;
795 struct rhashtable_params params = { 0 };
796 char *key = NULL;
797 struct aa_data *data;
798 int error = -EPROTO;
799 kernel_cap_t tmpcap;
800 u32 tmp;
801
802 *ns_name = NULL;
803
804 /* check that we have the right struct being passed */
805 if (!aa_unpack_nameX(e, AA_STRUCT, "profile"))
806 goto fail;
807 if (!aa_unpack_str(e, &name, NULL))
808 goto fail;
809 if (*name == '\0')
810 goto fail;
811
812 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
813 if (tmpns) {
814 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
815 if (!*ns_name) {
816 info = "out of memory";
817 error = -ENOMEM;
818 goto fail;
819 }
820 name = tmpname;
821 }
822
823 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
824 if (!profile) {
825 info = "out of memory";
826 error = -ENOMEM;
827 goto fail;
828 }
829 rules = list_first_entry(&profile->rules, typeof(*rules), list);
830
831 /* profile renaming is optional */
832 (void) aa_unpack_str(e, &profile->rename, "rename");
833
834 /* attachment string is optional */
835 (void) aa_unpack_str(e, &profile->attach.xmatch_str, "attach");
836
837 /* xmatch is optional and may be NULL */
838 error = unpack_pdb(e, &profile->attach.xmatch, false, false, &info);
839 if (error) {
840 info = "bad xmatch";
841 goto fail;
842 }
843
844 /* neither xmatch_len not xmatch_perms are optional if xmatch is set */
845 if (profile->attach.xmatch.dfa) {
846 if (!aa_unpack_u32(e, &tmp, NULL)) {
847 info = "missing xmatch len";
848 goto fail;
849 }
850 profile->attach.xmatch_len = tmp;
851 profile->attach.xmatch.start[AA_CLASS_XMATCH] = DFA_START;
852 error = aa_compat_map_xmatch(&profile->attach.xmatch);
853 if (error) {
854 info = "failed to convert xmatch permission table";
855 goto fail;
856 }
857 }
858
859 /* disconnected attachment string is optional */
860 (void) aa_unpack_str(e, &profile->disconnected, "disconnected");
861
862 /* per profile debug flags (complain, audit) */
863 if (!aa_unpack_nameX(e, AA_STRUCT, "flags")) {
864 info = "profile missing flags";
865 goto fail;
866 }
867 info = "failed to unpack profile flags";
868 if (!aa_unpack_u32(e, &tmp, NULL))
869 goto fail;
870 if (tmp & PACKED_FLAG_HAT)
871 profile->label.flags |= FLAG_HAT;
872 if (tmp & PACKED_FLAG_DEBUG1)
873 profile->label.flags |= FLAG_DEBUG1;
874 if (tmp & PACKED_FLAG_DEBUG2)
875 profile->label.flags |= FLAG_DEBUG2;
876 if (!aa_unpack_u32(e, &tmp, NULL))
877 goto fail;
878 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) {
879 profile->mode = APPARMOR_COMPLAIN;
880 } else if (tmp == PACKED_MODE_ENFORCE) {
881 profile->mode = APPARMOR_ENFORCE;
882 } else if (tmp == PACKED_MODE_KILL) {
883 profile->mode = APPARMOR_KILL;
884 } else if (tmp == PACKED_MODE_UNCONFINED) {
885 profile->mode = APPARMOR_UNCONFINED;
886 profile->label.flags |= FLAG_UNCONFINED;
887 } else if (tmp == PACKED_MODE_USER) {
888 profile->mode = APPARMOR_USER;
889 } else {
890 goto fail;
891 }
892 if (!aa_unpack_u32(e, &tmp, NULL))
893 goto fail;
894 if (tmp)
895 profile->audit = AUDIT_ALL;
896
897 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
898 goto fail;
899
900 /* path_flags is optional */
901 if (aa_unpack_u32(e, &profile->path_flags, "path_flags"))
902 profile->path_flags |= profile->label.flags &
903 PATH_MEDIATE_DELETED;
904 else
905 /* set a default value if path_flags field is not present */
906 profile->path_flags = PATH_MEDIATE_DELETED;
907
908 info = "failed to unpack profile capabilities";
909 if (!aa_unpack_u32(e, &(rules->caps.allow.cap[0]), NULL))
910 goto fail;
911 if (!aa_unpack_u32(e, &(rules->caps.audit.cap[0]), NULL))
912 goto fail;
913 if (!aa_unpack_u32(e, &(rules->caps.quiet.cap[0]), NULL))
914 goto fail;
915 if (!aa_unpack_u32(e, &tmpcap.cap[0], NULL))
916 goto fail;
917
918 info = "failed to unpack upper profile capabilities";
919 if (aa_unpack_nameX(e, AA_STRUCT, "caps64")) {
920 /* optional upper half of 64 bit caps */
921 if (!aa_unpack_u32(e, &(rules->caps.allow.cap[1]), NULL))
922 goto fail;
923 if (!aa_unpack_u32(e, &(rules->caps.audit.cap[1]), NULL))
924 goto fail;
925 if (!aa_unpack_u32(e, &(rules->caps.quiet.cap[1]), NULL))
926 goto fail;
927 if (!aa_unpack_u32(e, &(tmpcap.cap[1]), NULL))
928 goto fail;
929 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
930 goto fail;
931 }
932
933 info = "failed to unpack extended profile capabilities";
934 if (aa_unpack_nameX(e, AA_STRUCT, "capsx")) {
935 /* optional extended caps mediation mask */
936 if (!aa_unpack_u32(e, &(rules->caps.extended.cap[0]), NULL))
937 goto fail;
938 if (!aa_unpack_u32(e, &(rules->caps.extended.cap[1]), NULL))
939 goto fail;
940 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
941 goto fail;
942 }
943
944 if (!unpack_xattrs(e, profile)) {
945 info = "failed to unpack profile xattrs";
946 goto fail;
947 }
948
949 if (!unpack_rlimits(e, rules)) {
950 info = "failed to unpack profile rlimits";
951 goto fail;
952 }
953
954 if (!unpack_secmark(e, rules)) {
955 info = "failed to unpack profile secmark rules";
956 goto fail;
957 }
958
959 if (aa_unpack_nameX(e, AA_STRUCT, "policydb")) {
960 /* generic policy dfa - optional and may be NULL */
961 info = "failed to unpack policydb";
962 error = unpack_pdb(e, &rules->policy, true, false,
963 &info);
964 if (error)
965 goto fail;
966 /* Fixup: drop when we get rid of start array */
967 if (aa_dfa_next(rules->policy.dfa, rules->policy.start[0],
968 AA_CLASS_FILE))
969 rules->policy.start[AA_CLASS_FILE] =
970 aa_dfa_next(rules->policy.dfa,
971 rules->policy.start[0],
972 AA_CLASS_FILE);
973 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL))
974 goto fail;
975 error = aa_compat_map_policy(&rules->policy, e->version);
976 if (error) {
977 info = "failed to remap policydb permission table";
978 goto fail;
979 }
980 } else
981 rules->policy.dfa = aa_get_dfa(nulldfa);
982
983 /* get file rules */
984 error = unpack_pdb(e, &rules->file, false, true, &info);
985 if (error) {
986 goto fail;
987 } else if (rules->file.dfa) {
988 error = aa_compat_map_file(&rules->file);
989 if (error) {
990 info = "failed to remap file permission table";
991 goto fail;
992 }
993 } else if (rules->policy.dfa &&
994 rules->policy.start[AA_CLASS_FILE]) {
995 rules->file.dfa = aa_get_dfa(rules->policy.dfa);
996 rules->file.start[AA_CLASS_FILE] = rules->policy.start[AA_CLASS_FILE];
997 } else
998 rules->file.dfa = aa_get_dfa(nulldfa);
999
1000 error = -EPROTO;
1001 if (aa_unpack_nameX(e, AA_STRUCT, "data")) {
1002 info = "out of memory";
1003 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
1004 if (!profile->data) {
1005 error = -ENOMEM;
1006 goto fail;
1007 }
1008 params.nelem_hint = 3;
1009 params.key_len = sizeof(void *);
1010 params.key_offset = offsetof(struct aa_data, key);
1011 params.head_offset = offsetof(struct aa_data, head);
1012 params.hashfn = strhash;
1013 params.obj_cmpfn = datacmp;
1014
1015 if (rhashtable_init(profile->data, ¶ms)) {
1016 info = "failed to init key, value hash table";
1017 goto fail;
1018 }
1019
1020 while (aa_unpack_strdup(e, &key, NULL)) {
1021 data = kzalloc(sizeof(*data), GFP_KERNEL);
1022 if (!data) {
1023 kfree_sensitive(key);
1024 error = -ENOMEM;
1025 goto fail;
1026 }
1027
1028 data->key = key;
1029 data->size = aa_unpack_blob(e, &data->data, NULL);
1030 data->data = kvmemdup(data->data, data->size);
1031 if (data->size && !data->data) {
1032 kfree_sensitive(data->key);
1033 kfree_sensitive(data);
1034 error = -ENOMEM;
1035 goto fail;
1036 }
1037
1038 rhashtable_insert_fast(profile->data, &data->head,
1039 profile->data->p);
1040 }
1041
1042 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) {
1043 info = "failed to unpack end of key, value data table";
1044 goto fail;
1045 }
1046 }
1047
1048 if (!aa_unpack_nameX(e, AA_STRUCTEND, NULL)) {
1049 info = "failed to unpack end of profile";
1050 goto fail;
1051 }
1052
1053 return profile;
1054
1055fail:
1056 if (error == 0)
1057 /* default error covers most cases */
1058 error = -EPROTO;
1059 if (*ns_name) {
1060 kfree(*ns_name);
1061 *ns_name = NULL;
1062 }
1063 if (profile)
1064 name = NULL;
1065 else if (!name)
1066 name = "unknown";
1067 audit_iface(profile, NULL, name, info, e, error);
1068 aa_free_profile(profile);
1069
1070 return ERR_PTR(error);
1071}
1072
1073/**
1074 * verify_header - unpack serialized stream header
1075 * @e: serialized data read head (NOT NULL)
1076 * @required: whether the header is required or optional
1077 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
1078 *
1079 * Returns: error or 0 if header is good
1080 */
1081static int verify_header(struct aa_ext *e, int required, const char **ns)
1082{
1083 int error = -EPROTONOSUPPORT;
1084 const char *name = NULL;
1085 *ns = NULL;
1086
1087 /* get the interface version */
1088 if (!aa_unpack_u32(e, &e->version, "version")) {
1089 if (required) {
1090 audit_iface(NULL, NULL, NULL, "invalid profile format",
1091 e, error);
1092 return error;
1093 }
1094 }
1095
1096 /* Check that the interface version is currently supported.
1097 * if not specified use previous version
1098 * Mask off everything that is not kernel abi version
1099 */
1100 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v9)) {
1101 audit_iface(NULL, NULL, NULL, "unsupported interface version",
1102 e, error);
1103 return error;
1104 }
1105
1106 /* read the namespace if present */
1107 if (aa_unpack_str(e, &name, "namespace")) {
1108 if (*name == '\0') {
1109 audit_iface(NULL, NULL, NULL, "invalid namespace name",
1110 e, error);
1111 return error;
1112 }
1113 if (*ns && strcmp(*ns, name)) {
1114 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
1115 error);
1116 } else if (!*ns) {
1117 *ns = kstrdup(name, GFP_KERNEL);
1118 if (!*ns)
1119 return -ENOMEM;
1120 }
1121 }
1122
1123 return 0;
1124}
1125
1126static bool verify_xindex(int xindex, int table_size)
1127{
1128 int index, xtype;
1129 xtype = xindex & AA_X_TYPE_MASK;
1130 index = xindex & AA_X_INDEX_MASK;
1131 if (xtype == AA_X_TABLE && index >= table_size)
1132 return false;
1133 return true;
1134}
1135
1136/* verify dfa xindexes are in range of transition tables */
1137static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
1138{
1139 int i;
1140 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
1141 if (!verify_xindex(ACCEPT_TABLE(dfa)[i], table_size))
1142 return false;
1143 }
1144 return true;
1145}
1146
1147static bool verify_perm(struct aa_perms *perm)
1148{
1149 /* TODO: allow option to just force the perms into a valid state */
1150 if (perm->allow & perm->deny)
1151 return false;
1152 if (perm->subtree & ~perm->allow)
1153 return false;
1154 if (perm->cond & (perm->allow | perm->deny))
1155 return false;
1156 if (perm->kill & perm->allow)
1157 return false;
1158 if (perm->complain & (perm->allow | perm->deny))
1159 return false;
1160 if (perm->prompt & (perm->allow | perm->deny))
1161 return false;
1162 if (perm->complain & perm->prompt)
1163 return false;
1164 if (perm->hide & perm->allow)
1165 return false;
1166
1167 return true;
1168}
1169
1170static bool verify_perms(struct aa_policydb *pdb)
1171{
1172 int i;
1173
1174 for (i = 0; i < pdb->size; i++) {
1175 if (!verify_perm(&pdb->perms[i]))
1176 return false;
1177 /* verify indexes into str table */
1178 if (pdb->perms[i].xindex >= pdb->trans.size)
1179 return false;
1180 if (pdb->perms[i].tag >= pdb->trans.size)
1181 return false;
1182 if (pdb->perms[i].label >= pdb->trans.size)
1183 return false;
1184 }
1185
1186 return true;
1187}
1188
1189/**
1190 * verify_profile - Do post unpack analysis to verify profile consistency
1191 * @profile: profile to verify (NOT NULL)
1192 *
1193 * Returns: 0 if passes verification else error
1194 *
1195 * This verification is post any unpack mapping or changes
1196 */
1197static int verify_profile(struct aa_profile *profile)
1198{
1199 struct aa_ruleset *rules = list_first_entry(&profile->rules,
1200 typeof(*rules), list);
1201 if (!rules)
1202 return 0;
1203
1204 if ((rules->file.dfa && !verify_dfa_xindex(rules->file.dfa,
1205 rules->file.trans.size)) ||
1206 (rules->policy.dfa &&
1207 !verify_dfa_xindex(rules->policy.dfa, rules->policy.trans.size))) {
1208 audit_iface(profile, NULL, NULL,
1209 "Unpack: Invalid named transition", NULL, -EPROTO);
1210 return -EPROTO;
1211 }
1212
1213 if (!verify_perms(&rules->file)) {
1214 audit_iface(profile, NULL, NULL,
1215 "Unpack: Invalid perm index", NULL, -EPROTO);
1216 return -EPROTO;
1217 }
1218 if (!verify_perms(&rules->policy)) {
1219 audit_iface(profile, NULL, NULL,
1220 "Unpack: Invalid perm index", NULL, -EPROTO);
1221 return -EPROTO;
1222 }
1223 if (!verify_perms(&profile->attach.xmatch)) {
1224 audit_iface(profile, NULL, NULL,
1225 "Unpack: Invalid perm index", NULL, -EPROTO);
1226 return -EPROTO;
1227 }
1228
1229 return 0;
1230}
1231
1232void aa_load_ent_free(struct aa_load_ent *ent)
1233{
1234 if (ent) {
1235 aa_put_profile(ent->rename);
1236 aa_put_profile(ent->old);
1237 aa_put_profile(ent->new);
1238 kfree(ent->ns_name);
1239 kfree_sensitive(ent);
1240 }
1241}
1242
1243struct aa_load_ent *aa_load_ent_alloc(void)
1244{
1245 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1246 if (ent)
1247 INIT_LIST_HEAD(&ent->list);
1248 return ent;
1249}
1250
1251static int compress_zstd(const char *src, size_t slen, char **dst, size_t *dlen)
1252{
1253#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1254 const zstd_parameters params =
1255 zstd_get_params(aa_g_rawdata_compression_level, slen);
1256 const size_t wksp_len = zstd_cctx_workspace_bound(¶ms.cParams);
1257 void *wksp = NULL;
1258 zstd_cctx *ctx = NULL;
1259 size_t out_len = zstd_compress_bound(slen);
1260 void *out = NULL;
1261 int ret = 0;
1262
1263 out = kvzalloc(out_len, GFP_KERNEL);
1264 if (!out) {
1265 ret = -ENOMEM;
1266 goto cleanup;
1267 }
1268
1269 wksp = kvzalloc(wksp_len, GFP_KERNEL);
1270 if (!wksp) {
1271 ret = -ENOMEM;
1272 goto cleanup;
1273 }
1274
1275 ctx = zstd_init_cctx(wksp, wksp_len);
1276 if (!ctx) {
1277 ret = -EINVAL;
1278 goto cleanup;
1279 }
1280
1281 out_len = zstd_compress_cctx(ctx, out, out_len, src, slen, ¶ms);
1282 if (zstd_is_error(out_len) || out_len >= slen) {
1283 ret = -EINVAL;
1284 goto cleanup;
1285 }
1286
1287 if (is_vmalloc_addr(out)) {
1288 *dst = kvzalloc(out_len, GFP_KERNEL);
1289 if (*dst) {
1290 memcpy(*dst, out, out_len);
1291 kvfree(out);
1292 out = NULL;
1293 }
1294 } else {
1295 /*
1296 * If the staging buffer was kmalloc'd, then using krealloc is
1297 * probably going to be faster. The destination buffer will
1298 * always be smaller, so it's just shrunk, avoiding a memcpy
1299 */
1300 *dst = krealloc(out, out_len, GFP_KERNEL);
1301 }
1302
1303 if (!*dst) {
1304 ret = -ENOMEM;
1305 goto cleanup;
1306 }
1307
1308 *dlen = out_len;
1309
1310cleanup:
1311 if (ret) {
1312 kvfree(out);
1313 *dst = NULL;
1314 }
1315
1316 kvfree(wksp);
1317 return ret;
1318#else
1319 *dlen = slen;
1320 return 0;
1321#endif
1322}
1323
1324static int compress_loaddata(struct aa_loaddata *data)
1325{
1326 AA_BUG(data->compressed_size > 0);
1327
1328 /*
1329 * Shortcut the no compression case, else we increase the amount of
1330 * storage required by a small amount
1331 */
1332 if (aa_g_rawdata_compression_level != 0) {
1333 void *udata = data->data;
1334 int error = compress_zstd(udata, data->size, &data->data,
1335 &data->compressed_size);
1336 if (error) {
1337 data->compressed_size = data->size;
1338 return error;
1339 }
1340 if (udata != data->data)
1341 kvfree(udata);
1342 } else
1343 data->compressed_size = data->size;
1344
1345 return 0;
1346}
1347
1348/**
1349 * aa_unpack - unpack packed binary profile(s) data loaded from user space
1350 * @udata: user data copied to kmem (NOT NULL)
1351 * @lh: list to place unpacked profiles in a aa_repl_ws
1352 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1353 *
1354 * Unpack user data and return refcounted allocated profile(s) stored in
1355 * @lh in order of discovery, with the list chain stored in base.list
1356 * or error
1357 *
1358 * Returns: profile(s) on @lh else error pointer if fails to unpack
1359 */
1360int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1361 const char **ns)
1362{
1363 struct aa_load_ent *tmp, *ent;
1364 struct aa_profile *profile = NULL;
1365 char *ns_name = NULL;
1366 int error;
1367 struct aa_ext e = {
1368 .start = udata->data,
1369 .end = udata->data + udata->size,
1370 .pos = udata->data,
1371 };
1372
1373 *ns = NULL;
1374 while (e.pos < e.end) {
1375 void *start;
1376 error = verify_header(&e, e.pos == e.start, ns);
1377 if (error)
1378 goto fail;
1379
1380 start = e.pos;
1381 profile = unpack_profile(&e, &ns_name);
1382 if (IS_ERR(profile)) {
1383 error = PTR_ERR(profile);
1384 goto fail;
1385 }
1386
1387 error = verify_profile(profile);
1388 if (error)
1389 goto fail_profile;
1390
1391 if (aa_g_hash_policy)
1392 error = aa_calc_profile_hash(profile, e.version, start,
1393 e.pos - start);
1394 if (error)
1395 goto fail_profile;
1396
1397 ent = aa_load_ent_alloc();
1398 if (!ent) {
1399 error = -ENOMEM;
1400 goto fail_profile;
1401 }
1402
1403 ent->new = profile;
1404 ent->ns_name = ns_name;
1405 ns_name = NULL;
1406 list_add_tail(&ent->list, lh);
1407 }
1408 udata->abi = e.version & K_ABI_MASK;
1409 if (aa_g_hash_policy) {
1410 udata->hash = aa_calc_hash(udata->data, udata->size);
1411 if (IS_ERR(udata->hash)) {
1412 error = PTR_ERR(udata->hash);
1413 udata->hash = NULL;
1414 goto fail;
1415 }
1416 }
1417
1418 if (aa_g_export_binary) {
1419 error = compress_loaddata(udata);
1420 if (error)
1421 goto fail;
1422 }
1423 return 0;
1424
1425fail_profile:
1426 kfree(ns_name);
1427 aa_put_profile(profile);
1428
1429fail:
1430 list_for_each_entry_safe(ent, tmp, lh, list) {
1431 list_del_init(&ent->list);
1432 aa_load_ent_free(ent);
1433 }
1434
1435 return error;
1436}