apparmor: add the ability for policy to specify a permission table
[linux-2.6-block.git] / security / apparmor / policy_unpack.c
... / ...
CommitLineData
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 <linux/ctype.h>
18#include <linux/errno.h>
19#include <linux/zstd.h>
20
21#include "include/apparmor.h"
22#include "include/audit.h"
23#include "include/cred.h"
24#include "include/crypto.h"
25#include "include/file.h"
26#include "include/match.h"
27#include "include/path.h"
28#include "include/policy.h"
29#include "include/policy_unpack.h"
30#include "include/policy_compat.h"
31
32
33/*
34 * The AppArmor interface treats data as a type byte followed by the
35 * actual data. The interface has the notion of a named entry
36 * which has a name (AA_NAME typecode followed by name string) followed by
37 * the entries typecode and data. Named types allow for optional
38 * elements and extensions to be added and tested for without breaking
39 * backwards compatibility.
40 */
41
42enum aa_code {
43 AA_U8,
44 AA_U16,
45 AA_U32,
46 AA_U64,
47 AA_NAME, /* same as string except it is items name */
48 AA_STRING,
49 AA_BLOB,
50 AA_STRUCT,
51 AA_STRUCTEND,
52 AA_LIST,
53 AA_LISTEND,
54 AA_ARRAY,
55 AA_ARRAYEND,
56};
57
58/*
59 * aa_ext is the read of the buffer containing the serialized profile. The
60 * data is copied into a kernel buffer in apparmorfs and then handed off to
61 * the unpack routines.
62 */
63struct aa_ext {
64 void *start;
65 void *end;
66 void *pos; /* pointer to current position in the buffer */
67 u32 version;
68};
69
70#define tri int
71#define TRI_TRUE 1
72#define TRI_NONE 0
73#define TRI_FALSE -1
74
75/* audit callback for unpack fields */
76static void audit_cb(struct audit_buffer *ab, void *va)
77{
78 struct common_audit_data *sa = va;
79
80 if (aad(sa)->iface.ns) {
81 audit_log_format(ab, " ns=");
82 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
83 }
84 if (aad(sa)->name) {
85 audit_log_format(ab, " name=");
86 audit_log_untrustedstring(ab, aad(sa)->name);
87 }
88 if (aad(sa)->iface.pos)
89 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
90}
91
92/**
93 * audit_iface - do audit message for policy unpacking/load/replace/remove
94 * @new: profile if it has been allocated (MAYBE NULL)
95 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
96 * @name: name of the profile being manipulated (MAYBE NULL)
97 * @info: any extra info about the failure (MAYBE NULL)
98 * @e: buffer position info
99 * @error: error code
100 *
101 * Returns: %0 or error
102 */
103static int audit_iface(struct aa_profile *new, const char *ns_name,
104 const char *name, const char *info, struct aa_ext *e,
105 int error)
106{
107 struct aa_profile *profile = labels_profile(aa_current_raw_label());
108 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE, NULL);
109 if (e)
110 aad(&sa)->iface.pos = e->pos - e->start;
111 aad(&sa)->iface.ns = ns_name;
112 if (new)
113 aad(&sa)->name = new->base.hname;
114 else
115 aad(&sa)->name = name;
116 aad(&sa)->info = info;
117 aad(&sa)->error = error;
118
119 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
120}
121
122void __aa_loaddata_update(struct aa_loaddata *data, long revision)
123{
124 AA_BUG(!data);
125 AA_BUG(!data->ns);
126 AA_BUG(!mutex_is_locked(&data->ns->lock));
127 AA_BUG(data->revision > revision);
128
129 data->revision = revision;
130 if ((data->dents[AAFS_LOADDATA_REVISION])) {
131 d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
132 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
133 d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
134 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
135 }
136}
137
138bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
139{
140 if (l->size != r->size)
141 return false;
142 if (l->compressed_size != r->compressed_size)
143 return false;
144 if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
145 return false;
146 return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0;
147}
148
149/*
150 * need to take the ns mutex lock which is NOT safe most places that
151 * put_loaddata is called, so we have to delay freeing it
152 */
153static void do_loaddata_free(struct work_struct *work)
154{
155 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
156 struct aa_ns *ns = aa_get_ns(d->ns);
157
158 if (ns) {
159 mutex_lock_nested(&ns->lock, ns->level);
160 __aa_fs_remove_rawdata(d);
161 mutex_unlock(&ns->lock);
162 aa_put_ns(ns);
163 }
164
165 kfree_sensitive(d->hash);
166 kfree_sensitive(d->name);
167 kvfree(d->data);
168 kfree_sensitive(d);
169}
170
171void aa_loaddata_kref(struct kref *kref)
172{
173 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
174
175 if (d) {
176 INIT_WORK(&d->work, do_loaddata_free);
177 schedule_work(&d->work);
178 }
179}
180
181struct aa_loaddata *aa_loaddata_alloc(size_t size)
182{
183 struct aa_loaddata *d;
184
185 d = kzalloc(sizeof(*d), GFP_KERNEL);
186 if (d == NULL)
187 return ERR_PTR(-ENOMEM);
188 d->data = kvzalloc(size, GFP_KERNEL);
189 if (!d->data) {
190 kfree(d);
191 return ERR_PTR(-ENOMEM);
192 }
193 kref_init(&d->count);
194 INIT_LIST_HEAD(&d->list);
195
196 return d;
197}
198
199/* test if read will be in packed data bounds */
200static bool inbounds(struct aa_ext *e, size_t size)
201{
202 return (size <= e->end - e->pos);
203}
204
205static void *kvmemdup(const void *src, size_t len)
206{
207 void *p = kvmalloc(len, GFP_KERNEL);
208
209 if (p)
210 memcpy(p, src, len);
211 return p;
212}
213
214/**
215 * unpack_u16_chunk - test and do bounds checking for a u16 size based chunk
216 * @e: serialized data read head (NOT NULL)
217 * @chunk: start address for chunk of data (NOT NULL)
218 *
219 * Returns: the size of chunk found with the read head at the end of the chunk.
220 */
221static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
222{
223 size_t size = 0;
224 void *pos = e->pos;
225
226 if (!inbounds(e, sizeof(u16)))
227 goto fail;
228 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
229 e->pos += sizeof(__le16);
230 if (!inbounds(e, size))
231 goto fail;
232 *chunk = e->pos;
233 e->pos += size;
234 return size;
235
236fail:
237 e->pos = pos;
238 return 0;
239}
240
241/* unpack control byte */
242static bool unpack_X(struct aa_ext *e, enum aa_code code)
243{
244 if (!inbounds(e, 1))
245 return false;
246 if (*(u8 *) e->pos != code)
247 return false;
248 e->pos++;
249 return true;
250}
251
252/**
253 * unpack_nameX - check is the next element is of type X with a name of @name
254 * @e: serialized data extent information (NOT NULL)
255 * @code: type code
256 * @name: name to match to the serialized element. (MAYBE NULL)
257 *
258 * check that the next serialized data element is of type X and has a tag
259 * name @name. If @name is specified then there must be a matching
260 * name element in the stream. If @name is NULL any name element will be
261 * skipped and only the typecode will be tested.
262 *
263 * Returns true on success (both type code and name tests match) and the read
264 * head is advanced past the headers
265 *
266 * Returns: false if either match fails, the read head does not move
267 */
268static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
269{
270 /*
271 * May need to reset pos if name or type doesn't match
272 */
273 void *pos = e->pos;
274 /*
275 * Check for presence of a tagname, and if present name size
276 * AA_NAME tag value is a u16.
277 */
278 if (unpack_X(e, AA_NAME)) {
279 char *tag = NULL;
280 size_t size = unpack_u16_chunk(e, &tag);
281 /* if a name is specified it must match. otherwise skip tag */
282 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
283 goto fail;
284 } else if (name) {
285 /* if a name is specified and there is no name tag fail */
286 goto fail;
287 }
288
289 /* now check if type code matches */
290 if (unpack_X(e, code))
291 return true;
292
293fail:
294 e->pos = pos;
295 return false;
296}
297
298static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
299{
300 void *pos = e->pos;
301
302 if (unpack_nameX(e, AA_U8, name)) {
303 if (!inbounds(e, sizeof(u8)))
304 goto fail;
305 if (data)
306 *data = *((u8 *)e->pos);
307 e->pos += sizeof(u8);
308 return true;
309 }
310
311fail:
312 e->pos = pos;
313 return false;
314}
315
316static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
317{
318 void *pos = e->pos;
319
320 if (unpack_nameX(e, AA_U32, name)) {
321 if (!inbounds(e, sizeof(u32)))
322 goto fail;
323 if (data)
324 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
325 e->pos += sizeof(u32);
326 return true;
327 }
328
329fail:
330 e->pos = pos;
331 return false;
332}
333
334static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
335{
336 void *pos = e->pos;
337
338 if (unpack_nameX(e, AA_U64, name)) {
339 if (!inbounds(e, sizeof(u64)))
340 goto fail;
341 if (data)
342 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
343 e->pos += sizeof(u64);
344 return true;
345 }
346
347fail:
348 e->pos = pos;
349 return false;
350}
351
352static tri unpack_array(struct aa_ext *e, const char *name, u16 *size)
353{
354 void *pos = e->pos;
355
356 if (unpack_nameX(e, AA_ARRAY, name)) {
357 if (!inbounds(e, sizeof(u16)))
358 goto fail;
359 *size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
360 e->pos += sizeof(u16);
361 return TRI_TRUE;
362 }
363
364 return TRI_NONE;
365fail:
366 e->pos = pos;
367 return TRI_FALSE;
368}
369
370static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
371{
372 void *pos = e->pos;
373
374 if (unpack_nameX(e, AA_BLOB, name)) {
375 u32 size;
376 if (!inbounds(e, sizeof(u32)))
377 goto fail;
378 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
379 e->pos += sizeof(u32);
380 if (inbounds(e, (size_t) size)) {
381 *blob = e->pos;
382 e->pos += size;
383 return size;
384 }
385 }
386
387fail:
388 e->pos = pos;
389 return 0;
390}
391
392static int unpack_str(struct aa_ext *e, const char **string, const char *name)
393{
394 char *src_str;
395 size_t size = 0;
396 void *pos = e->pos;
397 *string = NULL;
398 if (unpack_nameX(e, AA_STRING, name)) {
399 size = unpack_u16_chunk(e, &src_str);
400 if (size) {
401 /* strings are null terminated, length is size - 1 */
402 if (src_str[size - 1] != 0)
403 goto fail;
404 *string = src_str;
405
406 return size;
407 }
408 }
409
410fail:
411 e->pos = pos;
412 return 0;
413}
414
415static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
416{
417 const char *tmp;
418 void *pos = e->pos;
419 int res = unpack_str(e, &tmp, name);
420 *string = NULL;
421
422 if (!res)
423 return 0;
424
425 *string = kmemdup(tmp, res, GFP_KERNEL);
426 if (!*string) {
427 e->pos = pos;
428 return 0;
429 }
430
431 return res;
432}
433
434
435/**
436 * unpack_dfa - unpack a file rule dfa
437 * @e: serialized data extent information (NOT NULL)
438 * @flags: dfa flags to check
439 *
440 * returns dfa or ERR_PTR or NULL if no dfa
441 */
442static struct aa_dfa *unpack_dfa(struct aa_ext *e, int flags)
443{
444 char *blob = NULL;
445 size_t size;
446 struct aa_dfa *dfa = NULL;
447
448 size = unpack_blob(e, &blob, "aadfa");
449 if (size) {
450 /*
451 * The dfa is aligned with in the blob to 8 bytes
452 * from the beginning of the stream.
453 * alignment adjust needed by dfa unpack
454 */
455 size_t sz = blob - (char *) e->start -
456 ((e->pos - e->start) & 7);
457 size_t pad = ALIGN(sz, 8) - sz;
458 if (aa_g_paranoid_load)
459 flags |= DFA_FLAG_VERIFY_STATES;
460 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
461
462 if (IS_ERR(dfa))
463 return dfa;
464
465 }
466
467 return dfa;
468}
469
470/**
471 * unpack_trans_table - unpack a profile transition table
472 * @e: serialized data extent information (NOT NULL)
473 * @table: str table to unpack to (NOT NULL)
474 *
475 * Returns: true if table successfully unpacked or not present
476 */
477static bool unpack_trans_table(struct aa_ext *e, struct aa_str_table *strs)
478{
479 void *saved_pos = e->pos;
480 char **table;
481
482 /* exec table is optional */
483 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
484 u16 size;
485 int i;
486
487 if (unpack_array(e, NULL, &size) != TRI_TRUE ||
488 size > (1 << 24))
489 /* currently 2^24 bits entries 0-3 */
490 goto fail;
491 table = kcalloc(size, sizeof(char *), GFP_KERNEL);
492 if (!table)
493 goto fail;
494
495 for (i = 0; i < size; i++) {
496 char *str;
497 int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
498 /* unpack_strdup verifies that the last character is
499 * null termination byte.
500 */
501 if (!size2)
502 goto fail;
503 table[i] = str;
504 /* verify that name doesn't start with space */
505 if (isspace(*str))
506 goto fail;
507
508 /* count internal # of internal \0 */
509 for (c = j = 0; j < size2 - 1; j++) {
510 if (!str[j]) {
511 pos = j;
512 c++;
513 }
514 }
515 if (*str == ':') {
516 /* first character after : must be valid */
517 if (!str[1])
518 goto fail;
519 /* beginning with : requires an embedded \0,
520 * verify that exactly 1 internal \0 exists
521 * trailing \0 already verified by unpack_strdup
522 *
523 * convert \0 back to : for label_parse
524 */
525 if (c == 1)
526 str[pos] = ':';
527 else if (c > 1)
528 goto fail;
529 } else if (c)
530 /* fail - all other cases with embedded \0 */
531 goto fail;
532 }
533 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
534 goto fail;
535 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
536 goto fail;
537
538 strs->table = table;
539 strs->size = size;
540 }
541 return true;
542
543fail:
544 kfree_sensitive(table);
545 e->pos = saved_pos;
546 return false;
547}
548
549static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
550{
551 void *pos = e->pos;
552
553 if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
554 u16 size;
555 int i;
556
557 if (unpack_array(e, NULL, &size) != TRI_TRUE)
558 goto fail;
559 profile->xattr_count = size;
560 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
561 if (!profile->xattrs)
562 goto fail;
563 for (i = 0; i < size; i++) {
564 if (!unpack_strdup(e, &profile->xattrs[i], NULL))
565 goto fail;
566 }
567 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
568 goto fail;
569 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
570 goto fail;
571 }
572
573 return true;
574
575fail:
576 e->pos = pos;
577 return false;
578}
579
580static bool unpack_secmark(struct aa_ext *e, struct aa_profile *profile)
581{
582 void *pos = e->pos;
583 u16 size;
584 int i;
585
586 if (unpack_nameX(e, AA_STRUCT, "secmark")) {
587 if (unpack_array(e, NULL, &size) != TRI_TRUE)
588 goto fail;
589
590 profile->secmark = kcalloc(size, sizeof(struct aa_secmark),
591 GFP_KERNEL);
592 if (!profile->secmark)
593 goto fail;
594
595 profile->secmark_count = size;
596
597 for (i = 0; i < size; i++) {
598 if (!unpack_u8(e, &profile->secmark[i].audit, NULL))
599 goto fail;
600 if (!unpack_u8(e, &profile->secmark[i].deny, NULL))
601 goto fail;
602 if (!unpack_strdup(e, &profile->secmark[i].label, NULL))
603 goto fail;
604 }
605 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
606 goto fail;
607 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
608 goto fail;
609 }
610
611 return true;
612
613fail:
614 if (profile->secmark) {
615 for (i = 0; i < size; i++)
616 kfree(profile->secmark[i].label);
617 kfree(profile->secmark);
618 profile->secmark_count = 0;
619 profile->secmark = NULL;
620 }
621
622 e->pos = pos;
623 return false;
624}
625
626static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
627{
628 void *pos = e->pos;
629
630 /* rlimits are optional */
631 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
632 u16 size;
633 int i;
634 u32 tmp = 0;
635 if (!unpack_u32(e, &tmp, NULL))
636 goto fail;
637 profile->rlimits.mask = tmp;
638
639 if (unpack_array(e, NULL, &size) != TRI_TRUE ||
640 size > RLIM_NLIMITS)
641 goto fail;
642 for (i = 0; i < size; i++) {
643 u64 tmp2 = 0;
644 int a = aa_map_resource(i);
645 if (!unpack_u64(e, &tmp2, NULL))
646 goto fail;
647 profile->rlimits.limits[a].rlim_max = tmp2;
648 }
649 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
650 goto fail;
651 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
652 goto fail;
653 }
654 return true;
655
656fail:
657 e->pos = pos;
658 return false;
659}
660
661static bool unpack_perm(struct aa_ext *e, u32 version, struct aa_perms *perm)
662{
663 bool res;
664
665 if (version != 1)
666 return false;
667
668 res = unpack_u32(e, &perm->allow, NULL);
669 res = res && unpack_u32(e, &perm->allow, NULL);
670 res = res && unpack_u32(e, &perm->deny, NULL);
671 res = res && unpack_u32(e, &perm->subtree, NULL);
672 res = res && unpack_u32(e, &perm->cond, NULL);
673 res = res && unpack_u32(e, &perm->kill, NULL);
674 res = res && unpack_u32(e, &perm->complain, NULL);
675 res = res && unpack_u32(e, &perm->prompt, NULL);
676 res = res && unpack_u32(e, &perm->audit, NULL);
677 res = res && unpack_u32(e, &perm->quiet, NULL);
678 res = res && unpack_u32(e, &perm->hide, NULL);
679 res = res && unpack_u32(e, &perm->xindex, NULL);
680 res = res && unpack_u32(e, &perm->tag, NULL);
681 res = res && unpack_u32(e, &perm->label, NULL);
682
683 return res;
684}
685
686static ssize_t unpack_perms_table(struct aa_ext *e, struct aa_perms **perms)
687{
688 void *pos = e->pos;
689 u16 size = 0;
690
691 AA_BUG(!perms);
692 /*
693 * policy perms are optional, in which case perms are embedded
694 * in the dfa accept table
695 */
696 if (unpack_nameX(e, AA_STRUCT, "perms")) {
697 int i;
698 u32 version;
699
700 if (!unpack_u32(e, &version, "version"))
701 goto fail_reset;
702 if (unpack_array(e, NULL, &size) != TRI_TRUE)
703 goto fail_reset;
704 *perms = kcalloc(size, sizeof(struct aa_perms), GFP_KERNEL);
705 if (!*perms)
706 goto fail_reset;
707 for (i = 0; i < size; i++) {
708 if (!unpack_perm(e, version, &(*perms)[i]))
709 goto fail;
710 }
711 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
712 goto fail;
713 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
714 goto fail;
715 } else
716 *perms = NULL;
717
718 return size;
719
720fail:
721 kfree(*perms);
722fail_reset:
723 e->pos = pos;
724 return -EPROTO;
725}
726
727static int unpack_pdb(struct aa_ext *e, struct aa_policydb *policy,
728 bool required_dfa, bool required_trans,
729 const char **info)
730{
731 void *pos = e->pos;
732 int i, flags, error = -EPROTO;
733
734 policy->size = unpack_perms_table(e, &policy->perms);
735 if (policy->size < 0) {
736 error = policy->size;
737 policy->perms = NULL;
738 *info = "failed to unpack - perms";
739 goto fail;
740 } else if (policy->perms) {
741 /* perms table present accept is index */
742 flags = TO_ACCEPT1_FLAG(YYTD_DATA32);
743 } else {
744 /* packed perms in accept1 and accept2 */
745 flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
746 TO_ACCEPT2_FLAG(YYTD_DATA32);
747 }
748
749 policy->dfa = unpack_dfa(e, flags);
750 if (IS_ERR(policy->dfa)) {
751 error = PTR_ERR(policy->dfa);
752 policy->dfa = NULL;
753 *info = "failed to unpack - dfa";
754 goto fail;
755 } else if (!policy->dfa) {
756 if (required_dfa) {
757 *info = "missing required dfa";
758 goto fail;
759 }
760 goto out;
761 }
762
763 /*
764 * only unpack the following if a dfa is present
765 *
766 * sadly start was given different names for file and policydb
767 * but since it is optional we can try both
768 */
769 if (!unpack_u32(e, &policy->start[0], "start"))
770 /* default start state */
771 policy->start[0] = DFA_START;
772 if (!unpack_u32(e, &policy->start[AA_CLASS_FILE], "dfa_start")) {
773 /* default start state for xmatch and file dfa */
774 policy->start[AA_CLASS_FILE] = DFA_START;
775 } /* setup class index */
776 for (i = AA_CLASS_FILE + 1; i <= AA_CLASS_LAST; i++) {
777 policy->start[i] = aa_dfa_next(policy->dfa, policy->start[0],
778 i);
779 }
780 if (!unpack_trans_table(e, &policy->trans) && required_trans) {
781 *info = "failed to unpack profile transition table";
782 goto fail;
783 }
784 /* TODO: move compat mapping here, requires dfa merging first */
785
786out:
787 return 0;
788
789fail:
790 e->pos = pos;
791 return error;
792}
793
794static u32 strhash(const void *data, u32 len, u32 seed)
795{
796 const char * const *key = data;
797
798 return jhash(*key, strlen(*key), seed);
799}
800
801static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
802{
803 const struct aa_data *data = obj;
804 const char * const *key = arg->key;
805
806 return strcmp(data->key, *key);
807}
808
809/**
810 * unpack_profile - unpack a serialized profile
811 * @e: serialized data extent information (NOT NULL)
812 * @ns_name: pointer of newly allocated copy of %NULL in case of error
813 *
814 * NOTE: unpack profile sets audit struct if there is a failure
815 */
816static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
817{
818 struct aa_profile *profile = NULL;
819 const char *tmpname, *tmpns = NULL, *name = NULL;
820 const char *info = "failed to unpack profile";
821 size_t ns_len;
822 struct rhashtable_params params = { 0 };
823 char *key = NULL;
824 struct aa_data *data;
825 int error = -EPROTO;
826 kernel_cap_t tmpcap;
827 u32 tmp;
828
829 *ns_name = NULL;
830
831 /* check that we have the right struct being passed */
832 if (!unpack_nameX(e, AA_STRUCT, "profile"))
833 goto fail;
834 if (!unpack_str(e, &name, NULL))
835 goto fail;
836 if (*name == '\0')
837 goto fail;
838
839 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
840 if (tmpns) {
841 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
842 if (!*ns_name) {
843 info = "out of memory";
844 goto fail;
845 }
846 name = tmpname;
847 }
848
849 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
850 if (!profile)
851 return ERR_PTR(-ENOMEM);
852
853 /* profile renaming is optional */
854 (void) unpack_str(e, &profile->rename, "rename");
855
856 /* attachment string is optional */
857 (void) unpack_str(e, &profile->attach, "attach");
858
859 /* xmatch is optional and may be NULL */
860 error = unpack_pdb(e, &profile->xmatch, false, false, &info);
861 if (error)
862 goto fail;
863
864 /* neither xmatch_len not xmatch_perms are optional if xmatch is set */
865 if (profile->xmatch.dfa) {
866 if (!unpack_u32(e, &tmp, NULL)) {
867 info = "missing xmatch len";
868 goto fail;
869 }
870 profile->xmatch_len = tmp;
871 profile->xmatch.start[AA_CLASS_XMATCH] = DFA_START;
872 if (aa_compat_map_xmatch(&profile->xmatch)) {
873 info = "failed to convert xmatch permission table";
874 goto fail;
875 }
876 }
877
878 /* disconnected attachment string is optional */
879 (void) unpack_str(e, &profile->disconnected, "disconnected");
880
881 /* per profile debug flags (complain, audit) */
882 if (!unpack_nameX(e, AA_STRUCT, "flags")) {
883 info = "profile missing flags";
884 goto fail;
885 }
886 info = "failed to unpack profile flags";
887 if (!unpack_u32(e, &tmp, NULL))
888 goto fail;
889 if (tmp & PACKED_FLAG_HAT)
890 profile->label.flags |= FLAG_HAT;
891 if (tmp & PACKED_FLAG_DEBUG1)
892 profile->label.flags |= FLAG_DEBUG1;
893 if (tmp & PACKED_FLAG_DEBUG2)
894 profile->label.flags |= FLAG_DEBUG2;
895 if (!unpack_u32(e, &tmp, NULL))
896 goto fail;
897 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) {
898 profile->mode = APPARMOR_COMPLAIN;
899 } else if (tmp == PACKED_MODE_ENFORCE) {
900 profile->mode = APPARMOR_ENFORCE;
901 } else if (tmp == PACKED_MODE_KILL) {
902 profile->mode = APPARMOR_KILL;
903 } else if (tmp == PACKED_MODE_UNCONFINED) {
904 profile->mode = APPARMOR_UNCONFINED;
905 profile->label.flags |= FLAG_UNCONFINED;
906 } else if (tmp == PACKED_MODE_USER) {
907 profile->mode = APPARMOR_USER;
908 } else {
909 goto fail;
910 }
911 if (!unpack_u32(e, &tmp, NULL))
912 goto fail;
913 if (tmp)
914 profile->audit = AUDIT_ALL;
915
916 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
917 goto fail;
918
919 /* path_flags is optional */
920 if (unpack_u32(e, &profile->path_flags, "path_flags"))
921 profile->path_flags |= profile->label.flags &
922 PATH_MEDIATE_DELETED;
923 else
924 /* set a default value if path_flags field is not present */
925 profile->path_flags = PATH_MEDIATE_DELETED;
926
927 info = "failed to unpack profile capabilities";
928 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
929 goto fail;
930 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
931 goto fail;
932 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
933 goto fail;
934 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
935 goto fail;
936
937 info = "failed to unpack upper profile capabilities";
938 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
939 /* optional upper half of 64 bit caps */
940 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
941 goto fail;
942 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
943 goto fail;
944 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
945 goto fail;
946 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
947 goto fail;
948 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
949 goto fail;
950 }
951
952 info = "failed to unpack extended profile capabilities";
953 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
954 /* optional extended caps mediation mask */
955 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
956 goto fail;
957 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
958 goto fail;
959 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
960 goto fail;
961 }
962
963 if (!unpack_xattrs(e, profile)) {
964 info = "failed to unpack profile xattrs";
965 goto fail;
966 }
967
968 if (!unpack_rlimits(e, profile)) {
969 info = "failed to unpack profile rlimits";
970 goto fail;
971 }
972
973 if (!unpack_secmark(e, profile)) {
974 info = "failed to unpack profile secmark rules";
975 goto fail;
976 }
977
978 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
979 /* generic policy dfa - optional and may be NULL */
980 info = "failed to unpack policydb";
981 error = unpack_pdb(e, &profile->policy, true, false, &info);
982 if (error)
983 goto fail;
984 /* Fixup: drop when we get rid of start array */
985 if (aa_dfa_next(profile->policy.dfa, profile->policy.start[0],
986 AA_CLASS_FILE))
987 profile->policy.start[AA_CLASS_FILE] =
988 aa_dfa_next(profile->policy.dfa,
989 profile->policy.start[0],
990 AA_CLASS_FILE);
991 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
992 goto fail;
993 if (aa_compat_map_policy(&profile->policy, e->version)) {
994 info = "failed to remap policydb permission table";
995 goto fail;
996 }
997 } else
998 profile->policy.dfa = aa_get_dfa(nulldfa);
999
1000 /* get file rules */
1001 error = unpack_pdb(e, &profile->file, false, true, &info);
1002 if (error) {
1003 goto fail;
1004 } else if (profile->file.dfa) {
1005 if (aa_compat_map_file(&profile->file)) {
1006 info = "failed to remap file permission table";
1007 goto fail;
1008 }
1009 } else if (profile->policy.dfa &&
1010 profile->policy.start[AA_CLASS_FILE]) {
1011 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
1012 profile->file.start[AA_CLASS_FILE] = profile->policy.start[AA_CLASS_FILE];
1013 } else
1014 profile->file.dfa = aa_get_dfa(nulldfa);
1015
1016 if (unpack_nameX(e, AA_STRUCT, "data")) {
1017 info = "out of memory";
1018 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
1019 if (!profile->data)
1020 goto fail;
1021
1022 params.nelem_hint = 3;
1023 params.key_len = sizeof(void *);
1024 params.key_offset = offsetof(struct aa_data, key);
1025 params.head_offset = offsetof(struct aa_data, head);
1026 params.hashfn = strhash;
1027 params.obj_cmpfn = datacmp;
1028
1029 if (rhashtable_init(profile->data, &params)) {
1030 info = "failed to init key, value hash table";
1031 goto fail;
1032 }
1033
1034 while (unpack_strdup(e, &key, NULL)) {
1035 data = kzalloc(sizeof(*data), GFP_KERNEL);
1036 if (!data) {
1037 kfree_sensitive(key);
1038 goto fail;
1039 }
1040
1041 data->key = key;
1042 data->size = unpack_blob(e, &data->data, NULL);
1043 data->data = kvmemdup(data->data, data->size);
1044 if (data->size && !data->data) {
1045 kfree_sensitive(data->key);
1046 kfree_sensitive(data);
1047 goto fail;
1048 }
1049
1050 rhashtable_insert_fast(profile->data, &data->head,
1051 profile->data->p);
1052 }
1053
1054 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
1055 info = "failed to unpack end of key, value data table";
1056 goto fail;
1057 }
1058 }
1059
1060 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
1061 info = "failed to unpack end of profile";
1062 goto fail;
1063 }
1064
1065 return profile;
1066
1067fail:
1068 if (profile)
1069 name = NULL;
1070 else if (!name)
1071 name = "unknown";
1072 audit_iface(profile, NULL, name, info, e, error);
1073 aa_free_profile(profile);
1074
1075 return ERR_PTR(error);
1076}
1077
1078/**
1079 * verify_header - unpack serialized stream header
1080 * @e: serialized data read head (NOT NULL)
1081 * @required: whether the header is required or optional
1082 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
1083 *
1084 * Returns: error or 0 if header is good
1085 */
1086static int verify_header(struct aa_ext *e, int required, const char **ns)
1087{
1088 int error = -EPROTONOSUPPORT;
1089 const char *name = NULL;
1090 *ns = NULL;
1091
1092 /* get the interface version */
1093 if (!unpack_u32(e, &e->version, "version")) {
1094 if (required) {
1095 audit_iface(NULL, NULL, NULL, "invalid profile format",
1096 e, error);
1097 return error;
1098 }
1099 }
1100
1101 /* Check that the interface version is currently supported.
1102 * if not specified use previous version
1103 * Mask off everything that is not kernel abi version
1104 */
1105 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v9)) {
1106 audit_iface(NULL, NULL, NULL, "unsupported interface version",
1107 e, error);
1108 return error;
1109 }
1110
1111 /* read the namespace if present */
1112 if (unpack_str(e, &name, "namespace")) {
1113 if (*name == '\0') {
1114 audit_iface(NULL, NULL, NULL, "invalid namespace name",
1115 e, error);
1116 return error;
1117 }
1118 if (*ns && strcmp(*ns, name)) {
1119 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
1120 error);
1121 } else if (!*ns) {
1122 *ns = kstrdup(name, GFP_KERNEL);
1123 if (!*ns)
1124 return -ENOMEM;
1125 }
1126 }
1127
1128 return 0;
1129}
1130
1131static bool verify_xindex(int xindex, int table_size)
1132{
1133 int index, xtype;
1134 xtype = xindex & AA_X_TYPE_MASK;
1135 index = xindex & AA_X_INDEX_MASK;
1136 if (xtype == AA_X_TABLE && index >= table_size)
1137 return false;
1138 return true;
1139}
1140
1141/* verify dfa xindexes are in range of transition tables */
1142static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
1143{
1144 int i;
1145 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
1146 if (!verify_xindex(ACCEPT_TABLE(dfa)[i], table_size))
1147 return false;
1148 }
1149 return true;
1150}
1151
1152/**
1153 * verify_profile - Do post unpack analysis to verify profile consistency
1154 * @profile: profile to verify (NOT NULL)
1155 *
1156 * Returns: 0 if passes verification else error
1157 *
1158 * This verification is post any unpack mapping or changes
1159 */
1160static int verify_profile(struct aa_profile *profile)
1161{
1162 if ((profile->file.dfa &&
1163 !verify_dfa_xindex(profile->file.dfa,
1164 profile->file.trans.size)) ||
1165 (profile->policy.dfa &&
1166 !verify_dfa_xindex(profile->policy.dfa,
1167 profile->policy.trans.size))) {
1168 audit_iface(profile, NULL, NULL,
1169 "Unpack: Invalid named transition", NULL, -EPROTO);
1170 return -EPROTO;
1171 }
1172
1173 return 0;
1174}
1175
1176void aa_load_ent_free(struct aa_load_ent *ent)
1177{
1178 if (ent) {
1179 aa_put_profile(ent->rename);
1180 aa_put_profile(ent->old);
1181 aa_put_profile(ent->new);
1182 kfree(ent->ns_name);
1183 kfree_sensitive(ent);
1184 }
1185}
1186
1187struct aa_load_ent *aa_load_ent_alloc(void)
1188{
1189 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1190 if (ent)
1191 INIT_LIST_HEAD(&ent->list);
1192 return ent;
1193}
1194
1195static int compress_zstd(const char *src, size_t slen, char **dst, size_t *dlen)
1196{
1197#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1198 const zstd_parameters params =
1199 zstd_get_params(aa_g_rawdata_compression_level, slen);
1200 const size_t wksp_len = zstd_cctx_workspace_bound(&params.cParams);
1201 void *wksp = NULL;
1202 zstd_cctx *ctx = NULL;
1203 size_t out_len = zstd_compress_bound(slen);
1204 void *out = NULL;
1205 int ret = 0;
1206
1207 out = kvzalloc(out_len, GFP_KERNEL);
1208 if (!out) {
1209 ret = -ENOMEM;
1210 goto cleanup;
1211 }
1212
1213 wksp = kvzalloc(wksp_len, GFP_KERNEL);
1214 if (!wksp) {
1215 ret = -ENOMEM;
1216 goto cleanup;
1217 }
1218
1219 ctx = zstd_init_cctx(wksp, wksp_len);
1220 if (!ctx) {
1221 ret = -EINVAL;
1222 goto cleanup;
1223 }
1224
1225 out_len = zstd_compress_cctx(ctx, out, out_len, src, slen, &params);
1226 if (zstd_is_error(out_len)) {
1227 ret = -EINVAL;
1228 goto cleanup;
1229 }
1230
1231 if (is_vmalloc_addr(out)) {
1232 *dst = kvzalloc(out_len, GFP_KERNEL);
1233 if (*dst) {
1234 memcpy(*dst, out, out_len);
1235 kvfree(out);
1236 out = NULL;
1237 }
1238 } else {
1239 /*
1240 * If the staging buffer was kmalloc'd, then using krealloc is
1241 * probably going to be faster. The destination buffer will
1242 * always be smaller, so it's just shrunk, avoiding a memcpy
1243 */
1244 *dst = krealloc(out, out_len, GFP_KERNEL);
1245 }
1246
1247 if (!*dst) {
1248 ret = -ENOMEM;
1249 goto cleanup;
1250 }
1251
1252 *dlen = out_len;
1253
1254cleanup:
1255 if (ret) {
1256 kvfree(out);
1257 *dst = NULL;
1258 }
1259
1260 kvfree(wksp);
1261 return ret;
1262#else
1263 *dlen = slen;
1264 return 0;
1265#endif
1266}
1267
1268static int compress_loaddata(struct aa_loaddata *data)
1269{
1270 AA_BUG(data->compressed_size > 0);
1271
1272 /*
1273 * Shortcut the no compression case, else we increase the amount of
1274 * storage required by a small amount
1275 */
1276 if (aa_g_rawdata_compression_level != 0) {
1277 void *udata = data->data;
1278 int error = compress_zstd(udata, data->size, &data->data,
1279 &data->compressed_size);
1280 if (error)
1281 return error;
1282
1283 if (udata != data->data)
1284 kvfree(udata);
1285 } else
1286 data->compressed_size = data->size;
1287
1288 return 0;
1289}
1290
1291/**
1292 * aa_unpack - unpack packed binary profile(s) data loaded from user space
1293 * @udata: user data copied to kmem (NOT NULL)
1294 * @lh: list to place unpacked profiles in a aa_repl_ws
1295 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1296 *
1297 * Unpack user data and return refcounted allocated profile(s) stored in
1298 * @lh in order of discovery, with the list chain stored in base.list
1299 * or error
1300 *
1301 * Returns: profile(s) on @lh else error pointer if fails to unpack
1302 */
1303int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1304 const char **ns)
1305{
1306 struct aa_load_ent *tmp, *ent;
1307 struct aa_profile *profile = NULL;
1308 int error;
1309 struct aa_ext e = {
1310 .start = udata->data,
1311 .end = udata->data + udata->size,
1312 .pos = udata->data,
1313 };
1314
1315 *ns = NULL;
1316 while (e.pos < e.end) {
1317 char *ns_name = NULL;
1318 void *start;
1319 error = verify_header(&e, e.pos == e.start, ns);
1320 if (error)
1321 goto fail;
1322
1323 start = e.pos;
1324 profile = unpack_profile(&e, &ns_name);
1325 if (IS_ERR(profile)) {
1326 error = PTR_ERR(profile);
1327 goto fail;
1328 }
1329
1330 error = verify_profile(profile);
1331 if (error)
1332 goto fail_profile;
1333
1334 if (aa_g_hash_policy)
1335 error = aa_calc_profile_hash(profile, e.version, start,
1336 e.pos - start);
1337 if (error)
1338 goto fail_profile;
1339
1340 ent = aa_load_ent_alloc();
1341 if (!ent) {
1342 error = -ENOMEM;
1343 goto fail_profile;
1344 }
1345
1346 ent->new = profile;
1347 ent->ns_name = ns_name;
1348 list_add_tail(&ent->list, lh);
1349 }
1350 udata->abi = e.version & K_ABI_MASK;
1351 if (aa_g_hash_policy) {
1352 udata->hash = aa_calc_hash(udata->data, udata->size);
1353 if (IS_ERR(udata->hash)) {
1354 error = PTR_ERR(udata->hash);
1355 udata->hash = NULL;
1356 goto fail;
1357 }
1358 }
1359
1360 if (aa_g_export_binary) {
1361 error = compress_loaddata(udata);
1362 if (error)
1363 goto fail;
1364 }
1365 return 0;
1366
1367fail_profile:
1368 aa_put_profile(profile);
1369
1370fail:
1371 list_for_each_entry_safe(ent, tmp, lh, list) {
1372 list_del_init(&ent->list);
1373 aa_load_ent_free(ent);
1374 }
1375
1376 return error;
1377}
1378
1379#ifdef CONFIG_SECURITY_APPARMOR_KUNIT_TEST
1380#include "policy_unpack_test.c"
1381#endif /* CONFIG_SECURITY_APPARMOR_KUNIT_TEST */