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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
20#include "include/apparmor.h"
21#include "include/audit.h"
22#include "include/cred.h"
23#include "include/crypto.h"
24#include "include/match.h"
25#include "include/path.h"
26#include "include/policy.h"
27#include "include/policy_unpack.h"
28
29#define K_ABI_MASK 0x3ff
30#define FORCE_COMPLAIN_FLAG 0x800
31#define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
32#define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
33
34#define v5 5 /* base version */
35#define v6 6 /* per entry policydb mediation check */
36#define v7 7
37#define v8 8 /* full network masking */
38
39/*
40 * The AppArmor interface treats data as a type byte followed by the
41 * actual data. The interface has the notion of a a named entry
42 * which has a name (AA_NAME typecode followed by name string) followed by
43 * the entries typecode and data. Named types allow for optional
44 * elements and extensions to be added and tested for without breaking
45 * backwards compatibility.
46 */
47
48enum aa_code {
49 AA_U8,
50 AA_U16,
51 AA_U32,
52 AA_U64,
53 AA_NAME, /* same as string except it is items name */
54 AA_STRING,
55 AA_BLOB,
56 AA_STRUCT,
57 AA_STRUCTEND,
58 AA_LIST,
59 AA_LISTEND,
60 AA_ARRAY,
61 AA_ARRAYEND,
62};
63
64/*
65 * aa_ext is the read of the buffer containing the serialized profile. The
66 * data is copied into a kernel buffer in apparmorfs and then handed off to
67 * the unpack routines.
68 */
69struct aa_ext {
70 void *start;
71 void *end;
72 void *pos; /* pointer to current position in the buffer */
73 u32 version;
74};
75
76/* audit callback for unpack fields */
77static void audit_cb(struct audit_buffer *ab, void *va)
78{
79 struct common_audit_data *sa = va;
80
81 if (aad(sa)->iface.ns) {
82 audit_log_format(ab, " ns=");
83 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
84 }
85 if (aad(sa)->name) {
86 audit_log_format(ab, " name=");
87 audit_log_untrustedstring(ab, aad(sa)->name);
88 }
89 if (aad(sa)->iface.pos)
90 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
91}
92
93/**
94 * audit_iface - do audit message for policy unpacking/load/replace/remove
95 * @new: profile if it has been allocated (MAYBE NULL)
96 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
97 * @name: name of the profile being manipulated (MAYBE NULL)
98 * @info: any extra info about the failure (MAYBE NULL)
99 * @e: buffer position info
100 * @error: error code
101 *
102 * Returns: %0 or error
103 */
104static int audit_iface(struct aa_profile *new, const char *ns_name,
105 const char *name, const char *info, struct aa_ext *e,
106 int error)
107{
108 struct aa_profile *profile = labels_profile(aa_current_raw_label());
109 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
110 if (e)
111 aad(&sa)->iface.pos = e->pos - e->start;
112 aad(&sa)->iface.ns = ns_name;
113 if (new)
114 aad(&sa)->name = new->base.hname;
115 else
116 aad(&sa)->name = name;
117 aad(&sa)->info = info;
118 aad(&sa)->error = error;
119
120 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
121}
122
123void __aa_loaddata_update(struct aa_loaddata *data, long revision)
124{
125 AA_BUG(!data);
126 AA_BUG(!data->ns);
127 AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
128 AA_BUG(!mutex_is_locked(&data->ns->lock));
129 AA_BUG(data->revision > revision);
130
131 data->revision = revision;
132 d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
133 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
134 d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
135 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
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 (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
143 return false;
144 return memcmp(l->data, r->data, r->size) == 0;
145}
146
147/*
148 * need to take the ns mutex lock which is NOT safe most places that
149 * put_loaddata is called, so we have to delay freeing it
150 */
151static void do_loaddata_free(struct work_struct *work)
152{
153 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
154 struct aa_ns *ns = aa_get_ns(d->ns);
155
156 if (ns) {
157 mutex_lock_nested(&ns->lock, ns->level);
158 __aa_fs_remove_rawdata(d);
159 mutex_unlock(&ns->lock);
160 aa_put_ns(ns);
161 }
162
163 kzfree(d->hash);
164 kzfree(d->name);
165 kvfree(d->data);
166 kzfree(d);
167}
168
169void aa_loaddata_kref(struct kref *kref)
170{
171 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
172
173 if (d) {
174 INIT_WORK(&d->work, do_loaddata_free);
175 schedule_work(&d->work);
176 }
177}
178
179struct aa_loaddata *aa_loaddata_alloc(size_t size)
180{
181 struct aa_loaddata *d;
182
183 d = kzalloc(sizeof(*d), GFP_KERNEL);
184 if (d == NULL)
185 return ERR_PTR(-ENOMEM);
186 d->data = kvzalloc(size, GFP_KERNEL);
187 if (!d->data) {
188 kfree(d);
189 return ERR_PTR(-ENOMEM);
190 }
191 kref_init(&d->count);
192 INIT_LIST_HEAD(&d->list);
193
194 return d;
195}
196
197/* test if read will be in packed data bounds */
198static bool inbounds(struct aa_ext *e, size_t size)
199{
200 return (size <= e->end - e->pos);
201}
202
203static void *kvmemdup(const void *src, size_t len)
204{
205 void *p = kvmalloc(len, GFP_KERNEL);
206
207 if (p)
208 memcpy(p, src, len);
209 return p;
210}
211
212/**
213 * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
214 * @e: serialized data read head (NOT NULL)
215 * @chunk: start address for chunk of data (NOT NULL)
216 *
217 * Returns: the size of chunk found with the read head at the end of the chunk.
218 */
219static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
220{
221 size_t size = 0;
222 void *pos = e->pos;
223
224 if (!inbounds(e, sizeof(u16)))
225 goto fail;
226 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
227 e->pos += sizeof(__le16);
228 if (!inbounds(e, size))
229 goto fail;
230 *chunk = e->pos;
231 e->pos += size;
232 return size;
233
234fail:
235 e->pos = pos;
236 return 0;
237}
238
239/* unpack control byte */
240static bool unpack_X(struct aa_ext *e, enum aa_code code)
241{
242 if (!inbounds(e, 1))
243 return 0;
244 if (*(u8 *) e->pos != code)
245 return 0;
246 e->pos++;
247 return 1;
248}
249
250/**
251 * unpack_nameX - check is the next element is of type X with a name of @name
252 * @e: serialized data extent information (NOT NULL)
253 * @code: type code
254 * @name: name to match to the serialized element. (MAYBE NULL)
255 *
256 * check that the next serialized data element is of type X and has a tag
257 * name @name. If @name is specified then there must be a matching
258 * name element in the stream. If @name is NULL any name element will be
259 * skipped and only the typecode will be tested.
260 *
261 * Returns 1 on success (both type code and name tests match) and the read
262 * head is advanced past the headers
263 *
264 * Returns: 0 if either match fails, the read head does not move
265 */
266static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
267{
268 /*
269 * May need to reset pos if name or type doesn't match
270 */
271 void *pos = e->pos;
272 /*
273 * Check for presence of a tagname, and if present name size
274 * AA_NAME tag value is a u16.
275 */
276 if (unpack_X(e, AA_NAME)) {
277 char *tag = NULL;
278 size_t size = unpack_u16_chunk(e, &tag);
279 /* if a name is specified it must match. otherwise skip tag */
280 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
281 goto fail;
282 } else if (name) {
283 /* if a name is specified and there is no name tag fail */
284 goto fail;
285 }
286
287 /* now check if type code matches */
288 if (unpack_X(e, code))
289 return 1;
290
291fail:
292 e->pos = pos;
293 return 0;
294}
295
296static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
297{
298 void *pos = e->pos;
299
300 if (unpack_nameX(e, AA_U8, name)) {
301 if (!inbounds(e, sizeof(u8)))
302 goto fail;
303 if (data)
304 *data = get_unaligned((u8 *)e->pos);
305 e->pos += sizeof(u8);
306 return 1;
307 }
308
309fail:
310 e->pos = pos;
311 return 0;
312}
313
314static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
315{
316 void *pos = e->pos;
317
318 if (unpack_nameX(e, AA_U32, name)) {
319 if (!inbounds(e, sizeof(u32)))
320 goto fail;
321 if (data)
322 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
323 e->pos += sizeof(u32);
324 return 1;
325 }
326
327fail:
328 e->pos = pos;
329 return 0;
330}
331
332static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
333{
334 void *pos = e->pos;
335
336 if (unpack_nameX(e, AA_U64, name)) {
337 if (!inbounds(e, sizeof(u64)))
338 goto fail;
339 if (data)
340 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
341 e->pos += sizeof(u64);
342 return 1;
343 }
344
345fail:
346 e->pos = pos;
347 return 0;
348}
349
350static size_t unpack_array(struct aa_ext *e, const char *name)
351{
352 void *pos = e->pos;
353
354 if (unpack_nameX(e, AA_ARRAY, name)) {
355 int size;
356 if (!inbounds(e, sizeof(u16)))
357 goto fail;
358 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
359 e->pos += sizeof(u16);
360 return size;
361 }
362
363fail:
364 e->pos = pos;
365 return 0;
366}
367
368static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
369{
370 void *pos = e->pos;
371
372 if (unpack_nameX(e, AA_BLOB, name)) {
373 u32 size;
374 if (!inbounds(e, sizeof(u32)))
375 goto fail;
376 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
377 e->pos += sizeof(u32);
378 if (inbounds(e, (size_t) size)) {
379 *blob = e->pos;
380 e->pos += size;
381 return size;
382 }
383 }
384
385fail:
386 e->pos = pos;
387 return 0;
388}
389
390static int unpack_str(struct aa_ext *e, const char **string, const char *name)
391{
392 char *src_str;
393 size_t size = 0;
394 void *pos = e->pos;
395 *string = NULL;
396 if (unpack_nameX(e, AA_STRING, name)) {
397 size = unpack_u16_chunk(e, &src_str);
398 if (size) {
399 /* strings are null terminated, length is size - 1 */
400 if (src_str[size - 1] != 0)
401 goto fail;
402 *string = src_str;
403
404 return size;
405 }
406 }
407
408fail:
409 e->pos = pos;
410 return 0;
411}
412
413static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
414{
415 const char *tmp;
416 void *pos = e->pos;
417 int res = unpack_str(e, &tmp, name);
418 *string = NULL;
419
420 if (!res)
421 return 0;
422
423 *string = kmemdup(tmp, res, GFP_KERNEL);
424 if (!*string) {
425 e->pos = pos;
426 return 0;
427 }
428
429 return res;
430}
431
432
433/**
434 * unpack_dfa - unpack a file rule dfa
435 * @e: serialized data extent information (NOT NULL)
436 *
437 * returns dfa or ERR_PTR or NULL if no dfa
438 */
439static struct aa_dfa *unpack_dfa(struct aa_ext *e)
440{
441 char *blob = NULL;
442 size_t size;
443 struct aa_dfa *dfa = NULL;
444
445 size = unpack_blob(e, &blob, "aadfa");
446 if (size) {
447 /*
448 * The dfa is aligned with in the blob to 8 bytes
449 * from the beginning of the stream.
450 * alignment adjust needed by dfa unpack
451 */
452 size_t sz = blob - (char *) e->start -
453 ((e->pos - e->start) & 7);
454 size_t pad = ALIGN(sz, 8) - sz;
455 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
456 TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
457 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
458
459 if (IS_ERR(dfa))
460 return dfa;
461
462 }
463
464 return dfa;
465}
466
467/**
468 * unpack_trans_table - unpack a profile transition table
469 * @e: serialized data extent information (NOT NULL)
470 * @profile: profile to add the accept table to (NOT NULL)
471 *
472 * Returns: 1 if table successfully unpacked
473 */
474static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
475{
476 void *saved_pos = e->pos;
477
478 /* exec table is optional */
479 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
480 int i, size;
481
482 size = unpack_array(e, NULL);
483 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
484 if (size > 16 - 4)
485 goto fail;
486 profile->file.trans.table = kcalloc(size, sizeof(char *),
487 GFP_KERNEL);
488 if (!profile->file.trans.table)
489 goto fail;
490
491 profile->file.trans.size = size;
492 for (i = 0; i < size; i++) {
493 char *str;
494 int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
495 /* unpack_strdup verifies that the last character is
496 * null termination byte.
497 */
498 if (!size2)
499 goto fail;
500 profile->file.trans.table[i] = str;
501 /* verify that name doesn't start with space */
502 if (isspace(*str))
503 goto fail;
504
505 /* count internal # of internal \0 */
506 for (c = j = 0; j < size2 - 1; j++) {
507 if (!str[j]) {
508 pos = j;
509 c++;
510 }
511 }
512 if (*str == ':') {
513 /* first character after : must be valid */
514 if (!str[1])
515 goto fail;
516 /* beginning with : requires an embedded \0,
517 * verify that exactly 1 internal \0 exists
518 * trailing \0 already verified by unpack_strdup
519 *
520 * convert \0 back to : for label_parse
521 */
522 if (c == 1)
523 str[pos] = ':';
524 else if (c > 1)
525 goto fail;
526 } else if (c)
527 /* fail - all other cases with embedded \0 */
528 goto fail;
529 }
530 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
531 goto fail;
532 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
533 goto fail;
534 }
535 return 1;
536
537fail:
538 aa_free_domain_entries(&profile->file.trans);
539 e->pos = saved_pos;
540 return 0;
541}
542
543static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
544{
545 void *pos = e->pos;
546
547 if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
548 int i, size;
549
550 size = unpack_array(e, NULL);
551 profile->xattr_count = size;
552 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
553 if (!profile->xattrs)
554 goto fail;
555 for (i = 0; i < size; i++) {
556 if (!unpack_strdup(e, &profile->xattrs[i], NULL))
557 goto fail;
558 }
559 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
560 goto fail;
561 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
562 goto fail;
563 }
564
565 return 1;
566
567fail:
568 e->pos = pos;
569 return 0;
570}
571
572static bool unpack_secmark(struct aa_ext *e, struct aa_profile *profile)
573{
574 void *pos = e->pos;
575 int i, size;
576
577 if (unpack_nameX(e, AA_STRUCT, "secmark")) {
578 size = unpack_array(e, NULL);
579
580 profile->secmark = kcalloc(size, sizeof(struct aa_secmark),
581 GFP_KERNEL);
582 if (!profile->secmark)
583 goto fail;
584
585 profile->secmark_count = size;
586
587 for (i = 0; i < size; i++) {
588 if (!unpack_u8(e, &profile->secmark[i].audit, NULL))
589 goto fail;
590 if (!unpack_u8(e, &profile->secmark[i].deny, NULL))
591 goto fail;
592 if (!unpack_strdup(e, &profile->secmark[i].label, NULL))
593 goto fail;
594 }
595 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
596 goto fail;
597 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
598 goto fail;
599 }
600
601 return 1;
602
603fail:
604 if (profile->secmark) {
605 for (i = 0; i < size; i++)
606 kfree(profile->secmark[i].label);
607 kfree(profile->secmark);
608 profile->secmark_count = 0;
609 profile->secmark = NULL;
610 }
611
612 e->pos = pos;
613 return 0;
614}
615
616static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
617{
618 void *pos = e->pos;
619
620 /* rlimits are optional */
621 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
622 int i, size;
623 u32 tmp = 0;
624 if (!unpack_u32(e, &tmp, NULL))
625 goto fail;
626 profile->rlimits.mask = tmp;
627
628 size = unpack_array(e, NULL);
629 if (size > RLIM_NLIMITS)
630 goto fail;
631 for (i = 0; i < size; i++) {
632 u64 tmp2 = 0;
633 int a = aa_map_resource(i);
634 if (!unpack_u64(e, &tmp2, NULL))
635 goto fail;
636 profile->rlimits.limits[a].rlim_max = tmp2;
637 }
638 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
639 goto fail;
640 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
641 goto fail;
642 }
643 return 1;
644
645fail:
646 e->pos = pos;
647 return 0;
648}
649
650static u32 strhash(const void *data, u32 len, u32 seed)
651{
652 const char * const *key = data;
653
654 return jhash(*key, strlen(*key), seed);
655}
656
657static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
658{
659 const struct aa_data *data = obj;
660 const char * const *key = arg->key;
661
662 return strcmp(data->key, *key);
663}
664
665/**
666 * unpack_profile - unpack a serialized profile
667 * @e: serialized data extent information (NOT NULL)
668 *
669 * NOTE: unpack profile sets audit struct if there is a failure
670 */
671static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
672{
673 struct aa_profile *profile = NULL;
674 const char *tmpname, *tmpns = NULL, *name = NULL;
675 const char *info = "failed to unpack profile";
676 size_t ns_len;
677 struct rhashtable_params params = { 0 };
678 char *key = NULL;
679 struct aa_data *data;
680 int i, error = -EPROTO;
681 kernel_cap_t tmpcap;
682 u32 tmp;
683
684 *ns_name = NULL;
685
686 /* check that we have the right struct being passed */
687 if (!unpack_nameX(e, AA_STRUCT, "profile"))
688 goto fail;
689 if (!unpack_str(e, &name, NULL))
690 goto fail;
691 if (*name == '\0')
692 goto fail;
693
694 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
695 if (tmpns) {
696 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
697 if (!*ns_name) {
698 info = "out of memory";
699 goto fail;
700 }
701 name = tmpname;
702 }
703
704 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
705 if (!profile)
706 return ERR_PTR(-ENOMEM);
707
708 /* profile renaming is optional */
709 (void) unpack_str(e, &profile->rename, "rename");
710
711 /* attachment string is optional */
712 (void) unpack_str(e, &profile->attach, "attach");
713
714 /* xmatch is optional and may be NULL */
715 profile->xmatch = unpack_dfa(e);
716 if (IS_ERR(profile->xmatch)) {
717 error = PTR_ERR(profile->xmatch);
718 profile->xmatch = NULL;
719 info = "bad xmatch";
720 goto fail;
721 }
722 /* xmatch_len is not optional if xmatch is set */
723 if (profile->xmatch) {
724 if (!unpack_u32(e, &tmp, NULL)) {
725 info = "missing xmatch len";
726 goto fail;
727 }
728 profile->xmatch_len = tmp;
729 }
730
731 /* disconnected attachment string is optional */
732 (void) unpack_str(e, &profile->disconnected, "disconnected");
733
734 /* per profile debug flags (complain, audit) */
735 if (!unpack_nameX(e, AA_STRUCT, "flags")) {
736 info = "profile missing flags";
737 goto fail;
738 }
739 info = "failed to unpack profile flags";
740 if (!unpack_u32(e, &tmp, NULL))
741 goto fail;
742 if (tmp & PACKED_FLAG_HAT)
743 profile->label.flags |= FLAG_HAT;
744 if (!unpack_u32(e, &tmp, NULL))
745 goto fail;
746 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
747 profile->mode = APPARMOR_COMPLAIN;
748 else if (tmp == PACKED_MODE_KILL)
749 profile->mode = APPARMOR_KILL;
750 else if (tmp == PACKED_MODE_UNCONFINED)
751 profile->mode = APPARMOR_UNCONFINED;
752 if (!unpack_u32(e, &tmp, NULL))
753 goto fail;
754 if (tmp)
755 profile->audit = AUDIT_ALL;
756
757 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
758 goto fail;
759
760 /* path_flags is optional */
761 if (unpack_u32(e, &profile->path_flags, "path_flags"))
762 profile->path_flags |= profile->label.flags &
763 PATH_MEDIATE_DELETED;
764 else
765 /* set a default value if path_flags field is not present */
766 profile->path_flags = PATH_MEDIATE_DELETED;
767
768 info = "failed to unpack profile capabilities";
769 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
770 goto fail;
771 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
772 goto fail;
773 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
774 goto fail;
775 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
776 goto fail;
777
778 info = "failed to unpack upper profile capabilities";
779 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
780 /* optional upper half of 64 bit caps */
781 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
782 goto fail;
783 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
784 goto fail;
785 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
786 goto fail;
787 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
788 goto fail;
789 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
790 goto fail;
791 }
792
793 info = "failed to unpack extended profile capabilities";
794 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
795 /* optional extended caps mediation mask */
796 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
797 goto fail;
798 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
799 goto fail;
800 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
801 goto fail;
802 }
803
804 if (!unpack_xattrs(e, profile)) {
805 info = "failed to unpack profile xattrs";
806 goto fail;
807 }
808
809 if (!unpack_rlimits(e, profile)) {
810 info = "failed to unpack profile rlimits";
811 goto fail;
812 }
813
814 if (!unpack_secmark(e, profile)) {
815 info = "failed to unpack profile secmark rules";
816 goto fail;
817 }
818
819 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
820 /* generic policy dfa - optional and may be NULL */
821 info = "failed to unpack policydb";
822 profile->policy.dfa = unpack_dfa(e);
823 if (IS_ERR(profile->policy.dfa)) {
824 error = PTR_ERR(profile->policy.dfa);
825 profile->policy.dfa = NULL;
826 goto fail;
827 } else if (!profile->policy.dfa) {
828 error = -EPROTO;
829 goto fail;
830 }
831 if (!unpack_u32(e, &profile->policy.start[0], "start"))
832 /* default start state */
833 profile->policy.start[0] = DFA_START;
834 /* setup class index */
835 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
836 profile->policy.start[i] =
837 aa_dfa_next(profile->policy.dfa,
838 profile->policy.start[0],
839 i);
840 }
841 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
842 goto fail;
843 } else
844 profile->policy.dfa = aa_get_dfa(nulldfa);
845
846 /* get file rules */
847 profile->file.dfa = unpack_dfa(e);
848 if (IS_ERR(profile->file.dfa)) {
849 error = PTR_ERR(profile->file.dfa);
850 profile->file.dfa = NULL;
851 info = "failed to unpack profile file rules";
852 goto fail;
853 } else if (profile->file.dfa) {
854 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
855 /* default start state */
856 profile->file.start = DFA_START;
857 } else if (profile->policy.dfa &&
858 profile->policy.start[AA_CLASS_FILE]) {
859 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
860 profile->file.start = profile->policy.start[AA_CLASS_FILE];
861 } else
862 profile->file.dfa = aa_get_dfa(nulldfa);
863
864 if (!unpack_trans_table(e, profile)) {
865 info = "failed to unpack profile transition table";
866 goto fail;
867 }
868
869 if (unpack_nameX(e, AA_STRUCT, "data")) {
870 info = "out of memory";
871 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
872 if (!profile->data)
873 goto fail;
874
875 params.nelem_hint = 3;
876 params.key_len = sizeof(void *);
877 params.key_offset = offsetof(struct aa_data, key);
878 params.head_offset = offsetof(struct aa_data, head);
879 params.hashfn = strhash;
880 params.obj_cmpfn = datacmp;
881
882 if (rhashtable_init(profile->data, ¶ms)) {
883 info = "failed to init key, value hash table";
884 goto fail;
885 }
886
887 while (unpack_strdup(e, &key, NULL)) {
888 data = kzalloc(sizeof(*data), GFP_KERNEL);
889 if (!data) {
890 kzfree(key);
891 goto fail;
892 }
893
894 data->key = key;
895 data->size = unpack_blob(e, &data->data, NULL);
896 data->data = kvmemdup(data->data, data->size);
897 if (data->size && !data->data) {
898 kzfree(data->key);
899 kzfree(data);
900 goto fail;
901 }
902
903 rhashtable_insert_fast(profile->data, &data->head,
904 profile->data->p);
905 }
906
907 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
908 info = "failed to unpack end of key, value data table";
909 goto fail;
910 }
911 }
912
913 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
914 info = "failed to unpack end of profile";
915 goto fail;
916 }
917
918 return profile;
919
920fail:
921 if (profile)
922 name = NULL;
923 else if (!name)
924 name = "unknown";
925 audit_iface(profile, NULL, name, info, e, error);
926 aa_free_profile(profile);
927
928 return ERR_PTR(error);
929}
930
931/**
932 * verify_head - unpack serialized stream header
933 * @e: serialized data read head (NOT NULL)
934 * @required: whether the header is required or optional
935 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
936 *
937 * Returns: error or 0 if header is good
938 */
939static int verify_header(struct aa_ext *e, int required, const char **ns)
940{
941 int error = -EPROTONOSUPPORT;
942 const char *name = NULL;
943 *ns = NULL;
944
945 /* get the interface version */
946 if (!unpack_u32(e, &e->version, "version")) {
947 if (required) {
948 audit_iface(NULL, NULL, NULL, "invalid profile format",
949 e, error);
950 return error;
951 }
952 }
953
954 /* Check that the interface version is currently supported.
955 * if not specified use previous version
956 * Mask off everything that is not kernel abi version
957 */
958 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
959 audit_iface(NULL, NULL, NULL, "unsupported interface version",
960 e, error);
961 return error;
962 }
963
964 /* read the namespace if present */
965 if (unpack_str(e, &name, "namespace")) {
966 if (*name == '\0') {
967 audit_iface(NULL, NULL, NULL, "invalid namespace name",
968 e, error);
969 return error;
970 }
971 if (*ns && strcmp(*ns, name))
972 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
973 error);
974 else if (!*ns)
975 *ns = name;
976 }
977
978 return 0;
979}
980
981static bool verify_xindex(int xindex, int table_size)
982{
983 int index, xtype;
984 xtype = xindex & AA_X_TYPE_MASK;
985 index = xindex & AA_X_INDEX_MASK;
986 if (xtype == AA_X_TABLE && index >= table_size)
987 return 0;
988 return 1;
989}
990
991/* verify dfa xindexes are in range of transition tables */
992static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
993{
994 int i;
995 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
996 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
997 return 0;
998 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
999 return 0;
1000 }
1001 return 1;
1002}
1003
1004/**
1005 * verify_profile - Do post unpack analysis to verify profile consistency
1006 * @profile: profile to verify (NOT NULL)
1007 *
1008 * Returns: 0 if passes verification else error
1009 */
1010static int verify_profile(struct aa_profile *profile)
1011{
1012 if (profile->file.dfa &&
1013 !verify_dfa_xindex(profile->file.dfa,
1014 profile->file.trans.size)) {
1015 audit_iface(profile, NULL, NULL, "Invalid named transition",
1016 NULL, -EPROTO);
1017 return -EPROTO;
1018 }
1019
1020 return 0;
1021}
1022
1023void aa_load_ent_free(struct aa_load_ent *ent)
1024{
1025 if (ent) {
1026 aa_put_profile(ent->rename);
1027 aa_put_profile(ent->old);
1028 aa_put_profile(ent->new);
1029 kfree(ent->ns_name);
1030 kzfree(ent);
1031 }
1032}
1033
1034struct aa_load_ent *aa_load_ent_alloc(void)
1035{
1036 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1037 if (ent)
1038 INIT_LIST_HEAD(&ent->list);
1039 return ent;
1040}
1041
1042/**
1043 * aa_unpack - unpack packed binary profile(s) data loaded from user space
1044 * @udata: user data copied to kmem (NOT NULL)
1045 * @lh: list to place unpacked profiles in a aa_repl_ws
1046 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1047 *
1048 * Unpack user data and return refcounted allocated profile(s) stored in
1049 * @lh in order of discovery, with the list chain stored in base.list
1050 * or error
1051 *
1052 * Returns: profile(s) on @lh else error pointer if fails to unpack
1053 */
1054int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1055 const char **ns)
1056{
1057 struct aa_load_ent *tmp, *ent;
1058 struct aa_profile *profile = NULL;
1059 int error;
1060 struct aa_ext e = {
1061 .start = udata->data,
1062 .end = udata->data + udata->size,
1063 .pos = udata->data,
1064 };
1065
1066 *ns = NULL;
1067 while (e.pos < e.end) {
1068 char *ns_name = NULL;
1069 void *start;
1070 error = verify_header(&e, e.pos == e.start, ns);
1071 if (error)
1072 goto fail;
1073
1074 start = e.pos;
1075 profile = unpack_profile(&e, &ns_name);
1076 if (IS_ERR(profile)) {
1077 error = PTR_ERR(profile);
1078 goto fail;
1079 }
1080
1081 error = verify_profile(profile);
1082 if (error)
1083 goto fail_profile;
1084
1085 if (aa_g_hash_policy)
1086 error = aa_calc_profile_hash(profile, e.version, start,
1087 e.pos - start);
1088 if (error)
1089 goto fail_profile;
1090
1091 ent = aa_load_ent_alloc();
1092 if (!ent) {
1093 error = -ENOMEM;
1094 goto fail_profile;
1095 }
1096
1097 ent->new = profile;
1098 ent->ns_name = ns_name;
1099 list_add_tail(&ent->list, lh);
1100 }
1101 udata->abi = e.version & K_ABI_MASK;
1102 if (aa_g_hash_policy) {
1103 udata->hash = aa_calc_hash(udata->data, udata->size);
1104 if (IS_ERR(udata->hash)) {
1105 error = PTR_ERR(udata->hash);
1106 udata->hash = NULL;
1107 goto fail;
1108 }
1109 }
1110 return 0;
1111
1112fail_profile:
1113 aa_put_profile(profile);
1114
1115fail:
1116 list_for_each_entry_safe(ent, tmp, lh, list) {
1117 list_del_init(&ent->list);
1118 aa_load_ent_free(ent);
1119 }
1120
1121 return error;
1122}
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}