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/zlib.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/match.h"
26 #include "include/path.h"
27 #include "include/policy.h"
28 #include "include/policy_unpack.h"
29
30 #define K_ABI_MASK 0x3ff
31 #define FORCE_COMPLAIN_FLAG 0x800
32 #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
33 #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
34
35 #define v5 5 /* base version */
36 #define v6 6 /* per entry policydb mediation check */
37 #define v7 7
38 #define v8 8 /* full network masking */
39
40 /*
41 * The AppArmor interface treats data as a type byte followed by the
42 * actual data. The interface has the notion of a named entry
43 * which has a name (AA_NAME typecode followed by name string) followed by
44 * the entries typecode and data. Named types allow for optional
45 * elements and extensions to be added and tested for without breaking
46 * backwards compatibility.
47 */
48
49 enum aa_code {
50 AA_U8,
51 AA_U16,
52 AA_U32,
53 AA_U64,
54 AA_NAME, /* same as string except it is items name */
55 AA_STRING,
56 AA_BLOB,
57 AA_STRUCT,
58 AA_STRUCTEND,
59 AA_LIST,
60 AA_LISTEND,
61 AA_ARRAY,
62 AA_ARRAYEND,
63 };
64
65 /*
66 * aa_ext is the read of the buffer containing the serialized profile. The
67 * data is copied into a kernel buffer in apparmorfs and then handed off to
68 * the unpack routines.
69 */
70 struct aa_ext {
71 void *start;
72 void *end;
73 void *pos; /* pointer to current position in the buffer */
74 u32 version;
75 };
76
77 /* audit callback for unpack fields */
audit_cb(struct audit_buffer * ab,void * va)78 static void audit_cb(struct audit_buffer *ab, void *va)
79 {
80 struct common_audit_data *sa = va;
81
82 if (aad(sa)->iface.ns) {
83 audit_log_format(ab, " ns=");
84 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
85 }
86 if (aad(sa)->name) {
87 audit_log_format(ab, " name=");
88 audit_log_untrustedstring(ab, aad(sa)->name);
89 }
90 if (aad(sa)->iface.pos)
91 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
92 }
93
94 /**
95 * audit_iface - do audit message for policy unpacking/load/replace/remove
96 * @new: profile if it has been allocated (MAYBE NULL)
97 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
98 * @name: name of the profile being manipulated (MAYBE NULL)
99 * @info: any extra info about the failure (MAYBE NULL)
100 * @e: buffer position info
101 * @error: error code
102 *
103 * Returns: %0 or error
104 */
audit_iface(struct aa_profile * new,const char * ns_name,const char * name,const char * info,struct aa_ext * e,int error)105 static int audit_iface(struct aa_profile *new, const char *ns_name,
106 const char *name, const char *info, struct aa_ext *e,
107 int error)
108 {
109 struct aa_profile *profile = labels_profile(aa_current_raw_label());
110 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
111 if (e)
112 aad(&sa)->iface.pos = e->pos - e->start;
113 aad(&sa)->iface.ns = ns_name;
114 if (new)
115 aad(&sa)->name = new->base.hname;
116 else
117 aad(&sa)->name = name;
118 aad(&sa)->info = info;
119 aad(&sa)->error = error;
120
121 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
122 }
123
__aa_loaddata_update(struct aa_loaddata * data,long revision)124 void __aa_loaddata_update(struct aa_loaddata *data, long revision)
125 {
126 AA_BUG(!data);
127 AA_BUG(!data->ns);
128 AA_BUG(!mutex_is_locked(&data->ns->lock));
129 AA_BUG(data->revision > revision);
130
131 data->revision = revision;
132 if ((data->dents[AAFS_LOADDATA_REVISION])) {
133 d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
134 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
135 d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
136 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
137 }
138 }
139
aa_rawdata_eq(struct aa_loaddata * l,struct aa_loaddata * r)140 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
141 {
142 if (l->size != r->size)
143 return false;
144 if (l->compressed_size != r->compressed_size)
145 return false;
146 if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
147 return false;
148 return memcmp(l->data, r->data, r->compressed_size ?: r->size) == 0;
149 }
150
151 /*
152 * need to take the ns mutex lock which is NOT safe most places that
153 * put_loaddata is called, so we have to delay freeing it
154 */
do_loaddata_free(struct work_struct * work)155 static void do_loaddata_free(struct work_struct *work)
156 {
157 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
158 struct aa_ns *ns = aa_get_ns(d->ns);
159
160 if (ns) {
161 mutex_lock_nested(&ns->lock, ns->level);
162 __aa_fs_remove_rawdata(d);
163 mutex_unlock(&ns->lock);
164 aa_put_ns(ns);
165 }
166
167 kfree_sensitive(d->hash);
168 kfree_sensitive(d->name);
169 kvfree(d->data);
170 kfree_sensitive(d);
171 }
172
aa_loaddata_kref(struct kref * kref)173 void aa_loaddata_kref(struct kref *kref)
174 {
175 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
176
177 if (d) {
178 INIT_WORK(&d->work, do_loaddata_free);
179 schedule_work(&d->work);
180 }
181 }
182
aa_loaddata_alloc(size_t size)183 struct aa_loaddata *aa_loaddata_alloc(size_t size)
184 {
185 struct aa_loaddata *d;
186
187 d = kzalloc(sizeof(*d), GFP_KERNEL);
188 if (d == NULL)
189 return ERR_PTR(-ENOMEM);
190 d->data = kvzalloc(size, GFP_KERNEL);
191 if (!d->data) {
192 kfree(d);
193 return ERR_PTR(-ENOMEM);
194 }
195 kref_init(&d->count);
196 INIT_LIST_HEAD(&d->list);
197
198 return d;
199 }
200
201 /* test if read will be in packed data bounds */
inbounds(struct aa_ext * e,size_t size)202 static bool inbounds(struct aa_ext *e, size_t size)
203 {
204 return (size <= e->end - e->pos);
205 }
206
kvmemdup(const void * src,size_t len)207 static void *kvmemdup(const void *src, size_t len)
208 {
209 void *p = kvmalloc(len, GFP_KERNEL);
210
211 if (p)
212 memcpy(p, src, len);
213 return p;
214 }
215
216 /**
217 * unpack_u16_chunk - test and do bounds checking for a u16 size based chunk
218 * @e: serialized data read head (NOT NULL)
219 * @chunk: start address for chunk of data (NOT NULL)
220 *
221 * Returns: the size of chunk found with the read head at the end of the chunk.
222 */
unpack_u16_chunk(struct aa_ext * e,char ** chunk)223 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
224 {
225 size_t size = 0;
226 void *pos = e->pos;
227
228 if (!inbounds(e, sizeof(u16)))
229 goto fail;
230 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
231 e->pos += sizeof(__le16);
232 if (!inbounds(e, size))
233 goto fail;
234 *chunk = e->pos;
235 e->pos += size;
236 return size;
237
238 fail:
239 e->pos = pos;
240 return 0;
241 }
242
243 /* unpack control byte */
unpack_X(struct aa_ext * e,enum aa_code code)244 static bool unpack_X(struct aa_ext *e, enum aa_code code)
245 {
246 if (!inbounds(e, 1))
247 return false;
248 if (*(u8 *) e->pos != code)
249 return false;
250 e->pos++;
251 return true;
252 }
253
254 /**
255 * unpack_nameX - check is the next element is of type X with a name of @name
256 * @e: serialized data extent information (NOT NULL)
257 * @code: type code
258 * @name: name to match to the serialized element. (MAYBE NULL)
259 *
260 * check that the next serialized data element is of type X and has a tag
261 * name @name. If @name is specified then there must be a matching
262 * name element in the stream. If @name is NULL any name element will be
263 * skipped and only the typecode will be tested.
264 *
265 * Returns true on success (both type code and name tests match) and the read
266 * head is advanced past the headers
267 *
268 * Returns: false if either match fails, the read head does not move
269 */
unpack_nameX(struct aa_ext * e,enum aa_code code,const char * name)270 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
271 {
272 /*
273 * May need to reset pos if name or type doesn't match
274 */
275 void *pos = e->pos;
276 /*
277 * Check for presence of a tagname, and if present name size
278 * AA_NAME tag value is a u16.
279 */
280 if (unpack_X(e, AA_NAME)) {
281 char *tag = NULL;
282 size_t size = unpack_u16_chunk(e, &tag);
283 /* if a name is specified it must match. otherwise skip tag */
284 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
285 goto fail;
286 } else if (name) {
287 /* if a name is specified and there is no name tag fail */
288 goto fail;
289 }
290
291 /* now check if type code matches */
292 if (unpack_X(e, code))
293 return true;
294
295 fail:
296 e->pos = pos;
297 return false;
298 }
299
unpack_u8(struct aa_ext * e,u8 * data,const char * name)300 static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
301 {
302 void *pos = e->pos;
303
304 if (unpack_nameX(e, AA_U8, name)) {
305 if (!inbounds(e, sizeof(u8)))
306 goto fail;
307 if (data)
308 *data = *((u8 *)e->pos);
309 e->pos += sizeof(u8);
310 return true;
311 }
312
313 fail:
314 e->pos = pos;
315 return false;
316 }
317
unpack_u32(struct aa_ext * e,u32 * data,const char * name)318 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
319 {
320 void *pos = e->pos;
321
322 if (unpack_nameX(e, AA_U32, name)) {
323 if (!inbounds(e, sizeof(u32)))
324 goto fail;
325 if (data)
326 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
327 e->pos += sizeof(u32);
328 return true;
329 }
330
331 fail:
332 e->pos = pos;
333 return false;
334 }
335
unpack_u64(struct aa_ext * e,u64 * data,const char * name)336 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
337 {
338 void *pos = e->pos;
339
340 if (unpack_nameX(e, AA_U64, name)) {
341 if (!inbounds(e, sizeof(u64)))
342 goto fail;
343 if (data)
344 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
345 e->pos += sizeof(u64);
346 return true;
347 }
348
349 fail:
350 e->pos = pos;
351 return false;
352 }
353
unpack_array(struct aa_ext * e,const char * name)354 static size_t unpack_array(struct aa_ext *e, const char *name)
355 {
356 void *pos = e->pos;
357
358 if (unpack_nameX(e, AA_ARRAY, name)) {
359 int size;
360 if (!inbounds(e, sizeof(u16)))
361 goto fail;
362 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
363 e->pos += sizeof(u16);
364 return size;
365 }
366
367 fail:
368 e->pos = pos;
369 return 0;
370 }
371
unpack_blob(struct aa_ext * e,char ** blob,const char * name)372 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
373 {
374 void *pos = e->pos;
375
376 if (unpack_nameX(e, AA_BLOB, name)) {
377 u32 size;
378 if (!inbounds(e, sizeof(u32)))
379 goto fail;
380 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
381 e->pos += sizeof(u32);
382 if (inbounds(e, (size_t) size)) {
383 *blob = e->pos;
384 e->pos += size;
385 return size;
386 }
387 }
388
389 fail:
390 e->pos = pos;
391 return 0;
392 }
393
unpack_str(struct aa_ext * e,const char ** string,const char * name)394 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
395 {
396 char *src_str;
397 size_t size = 0;
398 void *pos = e->pos;
399 *string = NULL;
400 if (unpack_nameX(e, AA_STRING, name)) {
401 size = unpack_u16_chunk(e, &src_str);
402 if (size) {
403 /* strings are null terminated, length is size - 1 */
404 if (src_str[size - 1] != 0)
405 goto fail;
406 *string = src_str;
407
408 return size;
409 }
410 }
411
412 fail:
413 e->pos = pos;
414 return 0;
415 }
416
unpack_strdup(struct aa_ext * e,char ** string,const char * name)417 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
418 {
419 const char *tmp;
420 void *pos = e->pos;
421 int res = unpack_str(e, &tmp, name);
422 *string = NULL;
423
424 if (!res)
425 return 0;
426
427 *string = kmemdup(tmp, res, GFP_KERNEL);
428 if (!*string) {
429 e->pos = pos;
430 return 0;
431 }
432
433 return res;
434 }
435
436
437 /**
438 * unpack_dfa - unpack a file rule dfa
439 * @e: serialized data extent information (NOT NULL)
440 *
441 * returns dfa or ERR_PTR or NULL if no dfa
442 */
unpack_dfa(struct aa_ext * e)443 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
444 {
445 char *blob = NULL;
446 size_t size;
447 struct aa_dfa *dfa = NULL;
448
449 size = unpack_blob(e, &blob, "aadfa");
450 if (size) {
451 /*
452 * The dfa is aligned with in the blob to 8 bytes
453 * from the beginning of the stream.
454 * alignment adjust needed by dfa unpack
455 */
456 size_t sz = blob - (char *) e->start -
457 ((e->pos - e->start) & 7);
458 size_t pad = ALIGN(sz, 8) - sz;
459 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
460 TO_ACCEPT2_FLAG(YYTD_DATA32);
461 if (aa_g_paranoid_load)
462 flags |= DFA_FLAG_VERIFY_STATES;
463 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
464
465 if (IS_ERR(dfa))
466 return dfa;
467
468 }
469
470 return dfa;
471 }
472
473 /**
474 * unpack_trans_table - unpack a profile transition table
475 * @e: serialized data extent information (NOT NULL)
476 * @profile: profile to add the accept table to (NOT NULL)
477 *
478 * Returns: true if table successfully unpacked
479 */
unpack_trans_table(struct aa_ext * e,struct aa_profile * profile)480 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
481 {
482 void *saved_pos = e->pos;
483
484 /* exec table is optional */
485 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
486 int i, size;
487
488 size = unpack_array(e, NULL);
489 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
490 if (size > 16 - 4)
491 goto fail;
492 profile->file.trans.table = kcalloc(size, sizeof(char *),
493 GFP_KERNEL);
494 if (!profile->file.trans.table)
495 goto fail;
496
497 profile->file.trans.size = size;
498 for (i = 0; i < size; i++) {
499 char *str;
500 int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
501 /* unpack_strdup verifies that the last character is
502 * null termination byte.
503 */
504 if (!size2)
505 goto fail;
506 profile->file.trans.table[i] = str;
507 /* verify that name doesn't start with space */
508 if (isspace(*str))
509 goto fail;
510
511 /* count internal # of internal \0 */
512 for (c = j = 0; j < size2 - 1; j++) {
513 if (!str[j]) {
514 pos = j;
515 c++;
516 }
517 }
518 if (*str == ':') {
519 /* first character after : must be valid */
520 if (!str[1])
521 goto fail;
522 /* beginning with : requires an embedded \0,
523 * verify that exactly 1 internal \0 exists
524 * trailing \0 already verified by unpack_strdup
525 *
526 * convert \0 back to : for label_parse
527 */
528 if (c == 1)
529 str[pos] = ':';
530 else if (c > 1)
531 goto fail;
532 } else if (c)
533 /* fail - all other cases with embedded \0 */
534 goto fail;
535 }
536 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
537 goto fail;
538 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
539 goto fail;
540 }
541 return true;
542
543 fail:
544 aa_free_domain_entries(&profile->file.trans);
545 e->pos = saved_pos;
546 return false;
547 }
548
unpack_xattrs(struct aa_ext * e,struct aa_profile * profile)549 static 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 int i, size;
555
556 size = unpack_array(e, NULL);
557 profile->xattr_count = size;
558 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
559 if (!profile->xattrs)
560 goto fail;
561 for (i = 0; i < size; i++) {
562 if (!unpack_strdup(e, &profile->xattrs[i], NULL))
563 goto fail;
564 }
565 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
566 goto fail;
567 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
568 goto fail;
569 }
570
571 return true;
572
573 fail:
574 e->pos = pos;
575 return false;
576 }
577
unpack_secmark(struct aa_ext * e,struct aa_profile * profile)578 static bool unpack_secmark(struct aa_ext *e, struct aa_profile *profile)
579 {
580 void *pos = e->pos;
581 int i, size;
582
583 if (unpack_nameX(e, AA_STRUCT, "secmark")) {
584 size = unpack_array(e, NULL);
585
586 profile->secmark = kcalloc(size, sizeof(struct aa_secmark),
587 GFP_KERNEL);
588 if (!profile->secmark)
589 goto fail;
590
591 profile->secmark_count = size;
592
593 for (i = 0; i < size; i++) {
594 if (!unpack_u8(e, &profile->secmark[i].audit, NULL))
595 goto fail;
596 if (!unpack_u8(e, &profile->secmark[i].deny, NULL))
597 goto fail;
598 if (!unpack_strdup(e, &profile->secmark[i].label, NULL))
599 goto fail;
600 }
601 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
602 goto fail;
603 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
604 goto fail;
605 }
606
607 return true;
608
609 fail:
610 if (profile->secmark) {
611 for (i = 0; i < size; i++)
612 kfree(profile->secmark[i].label);
613 kfree(profile->secmark);
614 profile->secmark_count = 0;
615 profile->secmark = NULL;
616 }
617
618 e->pos = pos;
619 return false;
620 }
621
unpack_rlimits(struct aa_ext * e,struct aa_profile * profile)622 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
623 {
624 void *pos = e->pos;
625
626 /* rlimits are optional */
627 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
628 int i, size;
629 u32 tmp = 0;
630 if (!unpack_u32(e, &tmp, NULL))
631 goto fail;
632 profile->rlimits.mask = tmp;
633
634 size = unpack_array(e, NULL);
635 if (size > RLIM_NLIMITS)
636 goto fail;
637 for (i = 0; i < size; i++) {
638 u64 tmp2 = 0;
639 int a = aa_map_resource(i);
640 if (!unpack_u64(e, &tmp2, NULL))
641 goto fail;
642 profile->rlimits.limits[a].rlim_max = tmp2;
643 }
644 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
645 goto fail;
646 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
647 goto fail;
648 }
649 return true;
650
651 fail:
652 e->pos = pos;
653 return false;
654 }
655
strhash(const void * data,u32 len,u32 seed)656 static u32 strhash(const void *data, u32 len, u32 seed)
657 {
658 const char * const *key = data;
659
660 return jhash(*key, strlen(*key), seed);
661 }
662
datacmp(struct rhashtable_compare_arg * arg,const void * obj)663 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
664 {
665 const struct aa_data *data = obj;
666 const char * const *key = arg->key;
667
668 return strcmp(data->key, *key);
669 }
670
671 /**
672 * unpack_profile - unpack a serialized profile
673 * @e: serialized data extent information (NOT NULL)
674 * @ns_name: pointer of newly allocated copy of %NULL in case of error
675 *
676 * NOTE: unpack profile sets audit struct if there is a failure
677 */
unpack_profile(struct aa_ext * e,char ** ns_name)678 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
679 {
680 struct aa_profile *profile = NULL;
681 const char *tmpname, *tmpns = NULL, *name = NULL;
682 const char *info = "failed to unpack profile";
683 size_t ns_len;
684 struct rhashtable_params params = { 0 };
685 char *key = NULL;
686 struct aa_data *data;
687 int i, error = -EPROTO;
688 kernel_cap_t tmpcap;
689 u32 tmp;
690
691 *ns_name = NULL;
692
693 /* check that we have the right struct being passed */
694 if (!unpack_nameX(e, AA_STRUCT, "profile"))
695 goto fail;
696 if (!unpack_str(e, &name, NULL))
697 goto fail;
698 if (*name == '\0')
699 goto fail;
700
701 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
702 if (tmpns) {
703 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
704 if (!*ns_name) {
705 info = "out of memory";
706 goto fail;
707 }
708 name = tmpname;
709 }
710
711 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
712 if (!profile)
713 return ERR_PTR(-ENOMEM);
714
715 /* profile renaming is optional */
716 (void) unpack_str(e, &profile->rename, "rename");
717
718 /* attachment string is optional */
719 (void) unpack_str(e, &profile->attach, "attach");
720
721 /* xmatch is optional and may be NULL */
722 profile->xmatch = unpack_dfa(e);
723 if (IS_ERR(profile->xmatch)) {
724 error = PTR_ERR(profile->xmatch);
725 profile->xmatch = NULL;
726 info = "bad xmatch";
727 goto fail;
728 }
729 /* xmatch_len is not optional if xmatch is set */
730 if (profile->xmatch) {
731 if (!unpack_u32(e, &tmp, NULL)) {
732 info = "missing xmatch len";
733 goto fail;
734 }
735 profile->xmatch_len = tmp;
736 }
737
738 /* disconnected attachment string is optional */
739 (void) unpack_str(e, &profile->disconnected, "disconnected");
740
741 /* per profile debug flags (complain, audit) */
742 if (!unpack_nameX(e, AA_STRUCT, "flags")) {
743 info = "profile missing flags";
744 goto fail;
745 }
746 info = "failed to unpack profile flags";
747 if (!unpack_u32(e, &tmp, NULL))
748 goto fail;
749 if (tmp & PACKED_FLAG_HAT)
750 profile->label.flags |= FLAG_HAT;
751 if (tmp & PACKED_FLAG_DEBUG1)
752 profile->label.flags |= FLAG_DEBUG1;
753 if (tmp & PACKED_FLAG_DEBUG2)
754 profile->label.flags |= FLAG_DEBUG2;
755 if (!unpack_u32(e, &tmp, NULL))
756 goto fail;
757 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG)) {
758 profile->mode = APPARMOR_COMPLAIN;
759 } else if (tmp == PACKED_MODE_ENFORCE) {
760 profile->mode = APPARMOR_ENFORCE;
761 } else if (tmp == PACKED_MODE_KILL) {
762 profile->mode = APPARMOR_KILL;
763 } else if (tmp == PACKED_MODE_UNCONFINED) {
764 profile->mode = APPARMOR_UNCONFINED;
765 profile->label.flags |= FLAG_UNCONFINED;
766 } else {
767 goto fail;
768 }
769 if (!unpack_u32(e, &tmp, NULL))
770 goto fail;
771 if (tmp)
772 profile->audit = AUDIT_ALL;
773
774 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
775 goto fail;
776
777 /* path_flags is optional */
778 if (unpack_u32(e, &profile->path_flags, "path_flags"))
779 profile->path_flags |= profile->label.flags &
780 PATH_MEDIATE_DELETED;
781 else
782 /* set a default value if path_flags field is not present */
783 profile->path_flags = PATH_MEDIATE_DELETED;
784
785 info = "failed to unpack profile capabilities";
786 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
787 goto fail;
788 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
789 goto fail;
790 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
791 goto fail;
792 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
793 goto fail;
794
795 info = "failed to unpack upper profile capabilities";
796 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
797 /* optional upper half of 64 bit caps */
798 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
799 goto fail;
800 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
801 goto fail;
802 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
803 goto fail;
804 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
805 goto fail;
806 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
807 goto fail;
808 }
809
810 info = "failed to unpack extended profile capabilities";
811 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
812 /* optional extended caps mediation mask */
813 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
814 goto fail;
815 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
816 goto fail;
817 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
818 goto fail;
819 }
820
821 if (!unpack_xattrs(e, profile)) {
822 info = "failed to unpack profile xattrs";
823 goto fail;
824 }
825
826 if (!unpack_rlimits(e, profile)) {
827 info = "failed to unpack profile rlimits";
828 goto fail;
829 }
830
831 if (!unpack_secmark(e, profile)) {
832 info = "failed to unpack profile secmark rules";
833 goto fail;
834 }
835
836 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
837 /* generic policy dfa - optional and may be NULL */
838 info = "failed to unpack policydb";
839 profile->policy.dfa = unpack_dfa(e);
840 if (IS_ERR(profile->policy.dfa)) {
841 error = PTR_ERR(profile->policy.dfa);
842 profile->policy.dfa = NULL;
843 goto fail;
844 } else if (!profile->policy.dfa) {
845 error = -EPROTO;
846 goto fail;
847 }
848 if (!unpack_u32(e, &profile->policy.start[0], "start"))
849 /* default start state */
850 profile->policy.start[0] = DFA_START;
851 /* setup class index */
852 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
853 profile->policy.start[i] =
854 aa_dfa_next(profile->policy.dfa,
855 profile->policy.start[0],
856 i);
857 }
858 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
859 goto fail;
860 } else
861 profile->policy.dfa = aa_get_dfa(nulldfa);
862
863 /* get file rules */
864 profile->file.dfa = unpack_dfa(e);
865 if (IS_ERR(profile->file.dfa)) {
866 error = PTR_ERR(profile->file.dfa);
867 profile->file.dfa = NULL;
868 info = "failed to unpack profile file rules";
869 goto fail;
870 } else if (profile->file.dfa) {
871 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
872 /* default start state */
873 profile->file.start = DFA_START;
874 } else if (profile->policy.dfa &&
875 profile->policy.start[AA_CLASS_FILE]) {
876 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
877 profile->file.start = profile->policy.start[AA_CLASS_FILE];
878 } else
879 profile->file.dfa = aa_get_dfa(nulldfa);
880
881 if (!unpack_trans_table(e, profile)) {
882 info = "failed to unpack profile transition table";
883 goto fail;
884 }
885
886 if (unpack_nameX(e, AA_STRUCT, "data")) {
887 info = "out of memory";
888 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
889 if (!profile->data)
890 goto fail;
891
892 params.nelem_hint = 3;
893 params.key_len = sizeof(void *);
894 params.key_offset = offsetof(struct aa_data, key);
895 params.head_offset = offsetof(struct aa_data, head);
896 params.hashfn = strhash;
897 params.obj_cmpfn = datacmp;
898
899 if (rhashtable_init(profile->data, ¶ms)) {
900 info = "failed to init key, value hash table";
901 goto fail;
902 }
903
904 while (unpack_strdup(e, &key, NULL)) {
905 data = kzalloc(sizeof(*data), GFP_KERNEL);
906 if (!data) {
907 kfree_sensitive(key);
908 goto fail;
909 }
910
911 data->key = key;
912 data->size = unpack_blob(e, &data->data, NULL);
913 data->data = kvmemdup(data->data, data->size);
914 if (data->size && !data->data) {
915 kfree_sensitive(data->key);
916 kfree_sensitive(data);
917 goto fail;
918 }
919
920 rhashtable_insert_fast(profile->data, &data->head,
921 profile->data->p);
922 }
923
924 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
925 info = "failed to unpack end of key, value data table";
926 goto fail;
927 }
928 }
929
930 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
931 info = "failed to unpack end of profile";
932 goto fail;
933 }
934
935 return profile;
936
937 fail:
938 if (profile)
939 name = NULL;
940 else if (!name)
941 name = "unknown";
942 audit_iface(profile, NULL, name, info, e, error);
943 aa_free_profile(profile);
944
945 return ERR_PTR(error);
946 }
947
948 /**
949 * verify_header - unpack serialized stream header
950 * @e: serialized data read head (NOT NULL)
951 * @required: whether the header is required or optional
952 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
953 *
954 * Returns: error or 0 if header is good
955 */
verify_header(struct aa_ext * e,int required,const char ** ns)956 static int verify_header(struct aa_ext *e, int required, const char **ns)
957 {
958 int error = -EPROTONOSUPPORT;
959 const char *name = NULL;
960 *ns = NULL;
961
962 /* get the interface version */
963 if (!unpack_u32(e, &e->version, "version")) {
964 if (required) {
965 audit_iface(NULL, NULL, NULL, "invalid profile format",
966 e, error);
967 return error;
968 }
969 }
970
971 /* Check that the interface version is currently supported.
972 * if not specified use previous version
973 * Mask off everything that is not kernel abi version
974 */
975 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
976 audit_iface(NULL, NULL, NULL, "unsupported interface version",
977 e, error);
978 return error;
979 }
980
981 /* read the namespace if present */
982 if (unpack_str(e, &name, "namespace")) {
983 if (*name == '\0') {
984 audit_iface(NULL, NULL, NULL, "invalid namespace name",
985 e, error);
986 return error;
987 }
988 if (*ns && strcmp(*ns, name)) {
989 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
990 error);
991 } else if (!*ns) {
992 *ns = kstrdup(name, GFP_KERNEL);
993 if (!*ns)
994 return -ENOMEM;
995 }
996 }
997
998 return 0;
999 }
1000
verify_xindex(int xindex,int table_size)1001 static bool verify_xindex(int xindex, int table_size)
1002 {
1003 int index, xtype;
1004 xtype = xindex & AA_X_TYPE_MASK;
1005 index = xindex & AA_X_INDEX_MASK;
1006 if (xtype == AA_X_TABLE && index >= table_size)
1007 return false;
1008 return true;
1009 }
1010
1011 /* verify dfa xindexes are in range of transition tables */
verify_dfa_xindex(struct aa_dfa * dfa,int table_size)1012 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
1013 {
1014 int i;
1015 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
1016 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
1017 return false;
1018 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
1019 return false;
1020 }
1021 return true;
1022 }
1023
1024 /**
1025 * verify_profile - Do post unpack analysis to verify profile consistency
1026 * @profile: profile to verify (NOT NULL)
1027 *
1028 * Returns: 0 if passes verification else error
1029 */
verify_profile(struct aa_profile * profile)1030 static int verify_profile(struct aa_profile *profile)
1031 {
1032 if (profile->file.dfa &&
1033 !verify_dfa_xindex(profile->file.dfa,
1034 profile->file.trans.size)) {
1035 audit_iface(profile, NULL, NULL, "Invalid named transition",
1036 NULL, -EPROTO);
1037 return -EPROTO;
1038 }
1039
1040 return 0;
1041 }
1042
aa_load_ent_free(struct aa_load_ent * ent)1043 void aa_load_ent_free(struct aa_load_ent *ent)
1044 {
1045 if (ent) {
1046 aa_put_profile(ent->rename);
1047 aa_put_profile(ent->old);
1048 aa_put_profile(ent->new);
1049 kfree(ent->ns_name);
1050 kfree_sensitive(ent);
1051 }
1052 }
1053
aa_load_ent_alloc(void)1054 struct aa_load_ent *aa_load_ent_alloc(void)
1055 {
1056 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1057 if (ent)
1058 INIT_LIST_HEAD(&ent->list);
1059 return ent;
1060 }
1061
deflate_compress(const char * src,size_t slen,char ** dst,size_t * dlen)1062 static int deflate_compress(const char *src, size_t slen, char **dst,
1063 size_t *dlen)
1064 {
1065 #ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1066 int error;
1067 struct z_stream_s strm;
1068 void *stgbuf, *dstbuf;
1069 size_t stglen = deflateBound(slen);
1070
1071 memset(&strm, 0, sizeof(strm));
1072
1073 if (stglen < slen)
1074 return -EFBIG;
1075
1076 strm.workspace = kvzalloc(zlib_deflate_workspacesize(MAX_WBITS,
1077 MAX_MEM_LEVEL),
1078 GFP_KERNEL);
1079 if (!strm.workspace)
1080 return -ENOMEM;
1081
1082 error = zlib_deflateInit(&strm, aa_g_rawdata_compression_level);
1083 if (error != Z_OK) {
1084 error = -ENOMEM;
1085 goto fail_deflate_init;
1086 }
1087
1088 stgbuf = kvzalloc(stglen, GFP_KERNEL);
1089 if (!stgbuf) {
1090 error = -ENOMEM;
1091 goto fail_stg_alloc;
1092 }
1093
1094 strm.next_in = src;
1095 strm.avail_in = slen;
1096 strm.next_out = stgbuf;
1097 strm.avail_out = stglen;
1098
1099 error = zlib_deflate(&strm, Z_FINISH);
1100 if (error != Z_STREAM_END) {
1101 error = -EINVAL;
1102 goto fail_deflate;
1103 }
1104 error = 0;
1105
1106 if (is_vmalloc_addr(stgbuf)) {
1107 dstbuf = kvzalloc(strm.total_out, GFP_KERNEL);
1108 if (dstbuf) {
1109 memcpy(dstbuf, stgbuf, strm.total_out);
1110 kvfree(stgbuf);
1111 }
1112 } else
1113 /*
1114 * If the staging buffer was kmalloc'd, then using krealloc is
1115 * probably going to be faster. The destination buffer will
1116 * always be smaller, so it's just shrunk, avoiding a memcpy
1117 */
1118 dstbuf = krealloc(stgbuf, strm.total_out, GFP_KERNEL);
1119
1120 if (!dstbuf) {
1121 error = -ENOMEM;
1122 goto fail_deflate;
1123 }
1124
1125 *dst = dstbuf;
1126 *dlen = strm.total_out;
1127
1128 fail_stg_alloc:
1129 zlib_deflateEnd(&strm);
1130 fail_deflate_init:
1131 kvfree(strm.workspace);
1132 return error;
1133
1134 fail_deflate:
1135 kvfree(stgbuf);
1136 goto fail_stg_alloc;
1137 #else
1138 *dlen = slen;
1139 return 0;
1140 #endif
1141 }
1142
compress_loaddata(struct aa_loaddata * data)1143 static int compress_loaddata(struct aa_loaddata *data)
1144 {
1145
1146 AA_BUG(data->compressed_size > 0);
1147
1148 /*
1149 * Shortcut the no compression case, else we increase the amount of
1150 * storage required by a small amount
1151 */
1152 if (aa_g_rawdata_compression_level != 0) {
1153 void *udata = data->data;
1154 int error = deflate_compress(udata, data->size, &data->data,
1155 &data->compressed_size);
1156 if (error)
1157 return error;
1158
1159 if (udata != data->data)
1160 kvfree(udata);
1161 } else
1162 data->compressed_size = data->size;
1163
1164 return 0;
1165 }
1166
1167 /**
1168 * aa_unpack - unpack packed binary profile(s) data loaded from user space
1169 * @udata: user data copied to kmem (NOT NULL)
1170 * @lh: list to place unpacked profiles in a aa_repl_ws
1171 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1172 *
1173 * Unpack user data and return refcounted allocated profile(s) stored in
1174 * @lh in order of discovery, with the list chain stored in base.list
1175 * or error
1176 *
1177 * Returns: profile(s) on @lh else error pointer if fails to unpack
1178 */
aa_unpack(struct aa_loaddata * udata,struct list_head * lh,const char ** ns)1179 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1180 const char **ns)
1181 {
1182 struct aa_load_ent *tmp, *ent;
1183 struct aa_profile *profile = NULL;
1184 int error;
1185 struct aa_ext e = {
1186 .start = udata->data,
1187 .end = udata->data + udata->size,
1188 .pos = udata->data,
1189 };
1190
1191 *ns = NULL;
1192 while (e.pos < e.end) {
1193 char *ns_name = NULL;
1194 void *start;
1195 error = verify_header(&e, e.pos == e.start, ns);
1196 if (error)
1197 goto fail;
1198
1199 start = e.pos;
1200 profile = unpack_profile(&e, &ns_name);
1201 if (IS_ERR(profile)) {
1202 error = PTR_ERR(profile);
1203 goto fail;
1204 }
1205
1206 error = verify_profile(profile);
1207 if (error)
1208 goto fail_profile;
1209
1210 if (aa_g_hash_policy)
1211 error = aa_calc_profile_hash(profile, e.version, start,
1212 e.pos - start);
1213 if (error)
1214 goto fail_profile;
1215
1216 ent = aa_load_ent_alloc();
1217 if (!ent) {
1218 error = -ENOMEM;
1219 goto fail_profile;
1220 }
1221
1222 ent->new = profile;
1223 ent->ns_name = ns_name;
1224 list_add_tail(&ent->list, lh);
1225 }
1226 udata->abi = e.version & K_ABI_MASK;
1227 if (aa_g_hash_policy) {
1228 udata->hash = aa_calc_hash(udata->data, udata->size);
1229 if (IS_ERR(udata->hash)) {
1230 error = PTR_ERR(udata->hash);
1231 udata->hash = NULL;
1232 goto fail;
1233 }
1234 }
1235
1236 if (aa_g_export_binary) {
1237 error = compress_loaddata(udata);
1238 if (error)
1239 goto fail;
1240 }
1241 return 0;
1242
1243 fail_profile:
1244 aa_put_profile(profile);
1245
1246 fail:
1247 list_for_each_entry_safe(ent, tmp, lh, list) {
1248 list_del_init(&ent->list);
1249 aa_load_ent_free(ent);
1250 }
1251
1252 return error;
1253 }
1254
1255 #ifdef CONFIG_SECURITY_APPARMOR_KUNIT_TEST
1256 #include "policy_unpack_test.c"
1257 #endif /* CONFIG_SECURITY_APPARMOR_KUNIT_TEST */
1258