xref: /linux/security/apparmor/policy_unpack.c (revision 73f488cd903938e78979d50e081a0314ad142351)
1 /*
2  * AppArmor security module
3  *
4  * This file contains AppArmor functions for unpacking policy loaded from
5  * userspace.
6  *
7  * Copyright (C) 1998-2008 Novell/SUSE
8  * Copyright 2009-2010 Canonical Ltd.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public License as
12  * published by the Free Software Foundation, version 2 of the
13  * License.
14  *
15  * AppArmor uses a serialized binary format for loading policy. To find
16  * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst
17  * All policy is validated before it is used.
18  */
19 
20 #include <asm/unaligned.h>
21 #include <linux/ctype.h>
22 #include <linux/errno.h>
23 
24 #include "include/apparmor.h"
25 #include "include/audit.h"
26 #include "include/cred.h"
27 #include "include/crypto.h"
28 #include "include/match.h"
29 #include "include/path.h"
30 #include "include/policy.h"
31 #include "include/policy_unpack.h"
32 
33 #define K_ABI_MASK 0x3ff
34 #define FORCE_COMPLAIN_FLAG 0x800
35 #define VERSION_LT(X, Y) (((X) & K_ABI_MASK) < ((Y) & K_ABI_MASK))
36 #define VERSION_GT(X, Y) (((X) & K_ABI_MASK) > ((Y) & K_ABI_MASK))
37 
38 #define v5	5	/* base version */
39 #define v6	6	/* per entry policydb mediation check */
40 #define v7	7	/* full network masking */
41 
42 /*
43  * The AppArmor interface treats data as a type byte followed by the
44  * actual data.  The interface has the notion of a a named entry
45  * which has a name (AA_NAME typecode followed by name string) followed by
46  * the entries typecode and data.  Named types allow for optional
47  * elements and extensions to be added and tested for without breaking
48  * backwards compatibility.
49  */
50 
51 enum aa_code {
52 	AA_U8,
53 	AA_U16,
54 	AA_U32,
55 	AA_U64,
56 	AA_NAME,		/* same as string except it is items name */
57 	AA_STRING,
58 	AA_BLOB,
59 	AA_STRUCT,
60 	AA_STRUCTEND,
61 	AA_LIST,
62 	AA_LISTEND,
63 	AA_ARRAY,
64 	AA_ARRAYEND,
65 };
66 
67 /*
68  * aa_ext is the read of the buffer containing the serialized profile.  The
69  * data is copied into a kernel buffer in apparmorfs and then handed off to
70  * the unpack routines.
71  */
72 struct aa_ext {
73 	void *start;
74 	void *end;
75 	void *pos;		/* pointer to current position in the buffer */
76 	u32 version;
77 };
78 
79 /* audit callback for unpack fields */
80 static void audit_cb(struct audit_buffer *ab, void *va)
81 {
82 	struct common_audit_data *sa = va;
83 
84 	if (aad(sa)->iface.ns) {
85 		audit_log_format(ab, " ns=");
86 		audit_log_untrustedstring(ab, aad(sa)->iface.ns);
87 	}
88 	if (aad(sa)->name) {
89 		audit_log_format(ab, " name=");
90 		audit_log_untrustedstring(ab, aad(sa)->name);
91 	}
92 	if (aad(sa)->iface.pos)
93 		audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
94 }
95 
96 /**
97  * audit_iface - do audit message for policy unpacking/load/replace/remove
98  * @new: profile if it has been allocated (MAYBE NULL)
99  * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
100  * @name: name of the profile being manipulated (MAYBE NULL)
101  * @info: any extra info about the failure (MAYBE NULL)
102  * @e: buffer position info
103  * @error: error code
104  *
105  * Returns: %0 or error
106  */
107 static int audit_iface(struct aa_profile *new, const char *ns_name,
108 		       const char *name, const char *info, struct aa_ext *e,
109 		       int error)
110 {
111 	struct aa_profile *profile = labels_profile(aa_current_raw_label());
112 	DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
113 	if (e)
114 		aad(&sa)->iface.pos = e->pos - e->start;
115 	aad(&sa)->iface.ns = ns_name;
116 	if (new)
117 		aad(&sa)->name = new->base.hname;
118 	else
119 		aad(&sa)->name = name;
120 	aad(&sa)->info = info;
121 	aad(&sa)->error = error;
122 
123 	return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
124 }
125 
126 void __aa_loaddata_update(struct aa_loaddata *data, long revision)
127 {
128 	AA_BUG(!data);
129 	AA_BUG(!data->ns);
130 	AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
131 	AA_BUG(!mutex_is_locked(&data->ns->lock));
132 	AA_BUG(data->revision > revision);
133 
134 	data->revision = revision;
135 	d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
136 		current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
137 	d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
138 		current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
139 }
140 
141 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
142 {
143 	if (l->size != r->size)
144 		return false;
145 	if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
146 		return false;
147 	return memcmp(l->data, r->data, r->size) == 0;
148 }
149 
150 /*
151  * need to take the ns mutex lock which is NOT safe most places that
152  * put_loaddata is called, so we have to delay freeing it
153  */
154 static void do_loaddata_free(struct work_struct *work)
155 {
156 	struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
157 	struct aa_ns *ns = aa_get_ns(d->ns);
158 
159 	if (ns) {
160 		mutex_lock_nested(&ns->lock, ns->level);
161 		__aa_fs_remove_rawdata(d);
162 		mutex_unlock(&ns->lock);
163 		aa_put_ns(ns);
164 	}
165 
166 	kzfree(d->hash);
167 	kzfree(d->name);
168 	kvfree(d->data);
169 	kzfree(d);
170 }
171 
172 void aa_loaddata_kref(struct kref *kref)
173 {
174 	struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
175 
176 	if (d) {
177 		INIT_WORK(&d->work, do_loaddata_free);
178 		schedule_work(&d->work);
179 	}
180 }
181 
182 struct aa_loaddata *aa_loaddata_alloc(size_t size)
183 {
184 	struct aa_loaddata *d;
185 
186 	d = kzalloc(sizeof(*d), GFP_KERNEL);
187 	if (d == NULL)
188 		return ERR_PTR(-ENOMEM);
189 	d->data = kvzalloc(size, GFP_KERNEL);
190 	if (!d->data) {
191 		kfree(d);
192 		return ERR_PTR(-ENOMEM);
193 	}
194 	kref_init(&d->count);
195 	INIT_LIST_HEAD(&d->list);
196 
197 	return d;
198 }
199 
200 /* test if read will be in packed data bounds */
201 static bool inbounds(struct aa_ext *e, size_t size)
202 {
203 	return (size <= e->end - e->pos);
204 }
205 
206 static void *kvmemdup(const void *src, size_t len)
207 {
208 	void *p = kvmalloc(len, GFP_KERNEL);
209 
210 	if (p)
211 		memcpy(p, src, len);
212 	return p;
213 }
214 
215 /**
216  * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
217  * @e: serialized data read head (NOT NULL)
218  * @chunk: start address for chunk of data (NOT NULL)
219  *
220  * Returns: the size of chunk found with the read head at the end of the chunk.
221  */
222 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
223 {
224 	size_t size = 0;
225 
226 	if (!inbounds(e, sizeof(u16)))
227 		return 0;
228 	size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
229 	e->pos += sizeof(__le16);
230 	if (!inbounds(e, size))
231 		return 0;
232 	*chunk = e->pos;
233 	e->pos += size;
234 	return size;
235 }
236 
237 /* unpack control byte */
238 static bool unpack_X(struct aa_ext *e, enum aa_code code)
239 {
240 	if (!inbounds(e, 1))
241 		return 0;
242 	if (*(u8 *) e->pos != code)
243 		return 0;
244 	e->pos++;
245 	return 1;
246 }
247 
248 /**
249  * unpack_nameX - check is the next element is of type X with a name of @name
250  * @e: serialized data extent information  (NOT NULL)
251  * @code: type code
252  * @name: name to match to the serialized element.  (MAYBE NULL)
253  *
254  * check that the next serialized data element is of type X and has a tag
255  * name @name.  If @name is specified then there must be a matching
256  * name element in the stream.  If @name is NULL any name element will be
257  * skipped and only the typecode will be tested.
258  *
259  * Returns 1 on success (both type code and name tests match) and the read
260  * head is advanced past the headers
261  *
262  * Returns: 0 if either match fails, the read head does not move
263  */
264 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
265 {
266 	/*
267 	 * May need to reset pos if name or type doesn't match
268 	 */
269 	void *pos = e->pos;
270 	/*
271 	 * Check for presence of a tagname, and if present name size
272 	 * AA_NAME tag value is a u16.
273 	 */
274 	if (unpack_X(e, AA_NAME)) {
275 		char *tag = NULL;
276 		size_t size = unpack_u16_chunk(e, &tag);
277 		/* if a name is specified it must match. otherwise skip tag */
278 		if (name && (!size || strcmp(name, tag)))
279 			goto fail;
280 	} else if (name) {
281 		/* if a name is specified and there is no name tag fail */
282 		goto fail;
283 	}
284 
285 	/* now check if type code matches */
286 	if (unpack_X(e, code))
287 		return 1;
288 
289 fail:
290 	e->pos = pos;
291 	return 0;
292 }
293 
294 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
295 {
296 	if (unpack_nameX(e, AA_U32, name)) {
297 		if (!inbounds(e, sizeof(u32)))
298 			return 0;
299 		if (data)
300 			*data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
301 		e->pos += sizeof(u32);
302 		return 1;
303 	}
304 	return 0;
305 }
306 
307 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
308 {
309 	if (unpack_nameX(e, AA_U64, name)) {
310 		if (!inbounds(e, sizeof(u64)))
311 			return 0;
312 		if (data)
313 			*data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
314 		e->pos += sizeof(u64);
315 		return 1;
316 	}
317 	return 0;
318 }
319 
320 static size_t unpack_array(struct aa_ext *e, const char *name)
321 {
322 	if (unpack_nameX(e, AA_ARRAY, name)) {
323 		int size;
324 		if (!inbounds(e, sizeof(u16)))
325 			return 0;
326 		size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
327 		e->pos += sizeof(u16);
328 		return size;
329 	}
330 	return 0;
331 }
332 
333 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
334 {
335 	if (unpack_nameX(e, AA_BLOB, name)) {
336 		u32 size;
337 		if (!inbounds(e, sizeof(u32)))
338 			return 0;
339 		size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
340 		e->pos += sizeof(u32);
341 		if (inbounds(e, (size_t) size)) {
342 			*blob = e->pos;
343 			e->pos += size;
344 			return size;
345 		}
346 	}
347 	return 0;
348 }
349 
350 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
351 {
352 	char *src_str;
353 	size_t size = 0;
354 	void *pos = e->pos;
355 	*string = NULL;
356 	if (unpack_nameX(e, AA_STRING, name)) {
357 		size = unpack_u16_chunk(e, &src_str);
358 		if (size) {
359 			/* strings are null terminated, length is size - 1 */
360 			if (src_str[size - 1] != 0)
361 				goto fail;
362 			*string = src_str;
363 		}
364 	}
365 	return size;
366 
367 fail:
368 	e->pos = pos;
369 	return 0;
370 }
371 
372 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
373 {
374 	const char *tmp;
375 	void *pos = e->pos;
376 	int res = unpack_str(e, &tmp, name);
377 	*string = NULL;
378 
379 	if (!res)
380 		return 0;
381 
382 	*string = kmemdup(tmp, res, GFP_KERNEL);
383 	if (!*string) {
384 		e->pos = pos;
385 		return 0;
386 	}
387 
388 	return res;
389 }
390 
391 #define DFA_VALID_PERM_MASK		0xffffffff
392 #define DFA_VALID_PERM2_MASK		0xffffffff
393 
394 /**
395  * verify_accept - verify the accept tables of a dfa
396  * @dfa: dfa to verify accept tables of (NOT NULL)
397  * @flags: flags governing dfa
398  *
399  * Returns: 1 if valid accept tables else 0 if error
400  */
401 static bool verify_accept(struct aa_dfa *dfa, int flags)
402 {
403 	int i;
404 
405 	/* verify accept permissions */
406 	for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
407 		int mode = ACCEPT_TABLE(dfa)[i];
408 
409 		if (mode & ~DFA_VALID_PERM_MASK)
410 			return 0;
411 
412 		if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
413 			return 0;
414 	}
415 	return 1;
416 }
417 
418 /**
419  * unpack_dfa - unpack a file rule dfa
420  * @e: serialized data extent information (NOT NULL)
421  *
422  * returns dfa or ERR_PTR or NULL if no dfa
423  */
424 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
425 {
426 	char *blob = NULL;
427 	size_t size;
428 	struct aa_dfa *dfa = NULL;
429 
430 	size = unpack_blob(e, &blob, "aadfa");
431 	if (size) {
432 		/*
433 		 * The dfa is aligned with in the blob to 8 bytes
434 		 * from the beginning of the stream.
435 		 * alignment adjust needed by dfa unpack
436 		 */
437 		size_t sz = blob - (char *) e->start -
438 			((e->pos - e->start) & 7);
439 		size_t pad = ALIGN(sz, 8) - sz;
440 		int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
441 			TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
442 		dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
443 
444 		if (IS_ERR(dfa))
445 			return dfa;
446 
447 		if (!verify_accept(dfa, flags))
448 			goto fail;
449 	}
450 
451 	return dfa;
452 
453 fail:
454 	aa_put_dfa(dfa);
455 	return ERR_PTR(-EPROTO);
456 }
457 
458 /**
459  * unpack_trans_table - unpack a profile transition table
460  * @e: serialized data extent information  (NOT NULL)
461  * @profile: profile to add the accept table to (NOT NULL)
462  *
463  * Returns: 1 if table successfully unpacked
464  */
465 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
466 {
467 	void *saved_pos = e->pos;
468 
469 	/* exec table is optional */
470 	if (unpack_nameX(e, AA_STRUCT, "xtable")) {
471 		int i, size;
472 
473 		size = unpack_array(e, NULL);
474 		/* currently 4 exec bits and entries 0-3 are reserved iupcx */
475 		if (size > 16 - 4)
476 			goto fail;
477 		profile->file.trans.table = kzalloc(sizeof(char *) * size,
478 						    GFP_KERNEL);
479 		if (!profile->file.trans.table)
480 			goto fail;
481 
482 		profile->file.trans.size = size;
483 		for (i = 0; i < size; i++) {
484 			char *str;
485 			int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
486 			/* unpack_strdup verifies that the last character is
487 			 * null termination byte.
488 			 */
489 			if (!size2)
490 				goto fail;
491 			profile->file.trans.table[i] = str;
492 			/* verify that name doesn't start with space */
493 			if (isspace(*str))
494 				goto fail;
495 
496 			/* count internal #  of internal \0 */
497 			for (c = j = 0; j < size2 - 1; j++) {
498 				if (!str[j]) {
499 					pos = j;
500 					c++;
501 				}
502 			}
503 			if (*str == ':') {
504 				/* first character after : must be valid */
505 				if (!str[1])
506 					goto fail;
507 				/* beginning with : requires an embedded \0,
508 				 * verify that exactly 1 internal \0 exists
509 				 * trailing \0 already verified by unpack_strdup
510 				 *
511 				 * convert \0 back to : for label_parse
512 				 */
513 				if (c == 1)
514 					str[pos] = ':';
515 				else if (c > 1)
516 					goto fail;
517 			} else if (c)
518 				/* fail - all other cases with embedded \0 */
519 				goto fail;
520 		}
521 		if (!unpack_nameX(e, AA_ARRAYEND, NULL))
522 			goto fail;
523 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
524 			goto fail;
525 	}
526 	return 1;
527 
528 fail:
529 	aa_free_domain_entries(&profile->file.trans);
530 	e->pos = saved_pos;
531 	return 0;
532 }
533 
534 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
535 {
536 	void *pos = e->pos;
537 
538 	if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
539 		int i, size;
540 
541 		size = unpack_array(e, NULL);
542 		profile->xattr_count = size;
543 		profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
544 		if (!profile->xattrs)
545 			goto fail;
546 		for (i = 0; i < size; i++) {
547 			if (!unpack_strdup(e, &profile->xattrs[i], NULL))
548 				goto fail;
549 		}
550 		if (!unpack_nameX(e, AA_ARRAYEND, NULL))
551 			goto fail;
552 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
553 			goto fail;
554 	}
555 
556 	return 1;
557 
558 fail:
559 	e->pos = pos;
560 	return 0;
561 }
562 
563 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
564 {
565 	void *pos = e->pos;
566 
567 	/* rlimits are optional */
568 	if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
569 		int i, size;
570 		u32 tmp = 0;
571 		if (!unpack_u32(e, &tmp, NULL))
572 			goto fail;
573 		profile->rlimits.mask = tmp;
574 
575 		size = unpack_array(e, NULL);
576 		if (size > RLIM_NLIMITS)
577 			goto fail;
578 		for (i = 0; i < size; i++) {
579 			u64 tmp2 = 0;
580 			int a = aa_map_resource(i);
581 			if (!unpack_u64(e, &tmp2, NULL))
582 				goto fail;
583 			profile->rlimits.limits[a].rlim_max = tmp2;
584 		}
585 		if (!unpack_nameX(e, AA_ARRAYEND, NULL))
586 			goto fail;
587 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
588 			goto fail;
589 	}
590 	return 1;
591 
592 fail:
593 	e->pos = pos;
594 	return 0;
595 }
596 
597 static u32 strhash(const void *data, u32 len, u32 seed)
598 {
599 	const char * const *key = data;
600 
601 	return jhash(*key, strlen(*key), seed);
602 }
603 
604 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
605 {
606 	const struct aa_data *data = obj;
607 	const char * const *key = arg->key;
608 
609 	return strcmp(data->key, *key);
610 }
611 
612 /**
613  * unpack_profile - unpack a serialized profile
614  * @e: serialized data extent information (NOT NULL)
615  *
616  * NOTE: unpack profile sets audit struct if there is a failure
617  */
618 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
619 {
620 	struct aa_profile *profile = NULL;
621 	const char *tmpname, *tmpns = NULL, *name = NULL;
622 	const char *info = "failed to unpack profile";
623 	size_t ns_len;
624 	struct rhashtable_params params = { 0 };
625 	char *key = NULL;
626 	struct aa_data *data;
627 	int i, error = -EPROTO;
628 	kernel_cap_t tmpcap;
629 	u32 tmp;
630 
631 	*ns_name = NULL;
632 
633 	/* check that we have the right struct being passed */
634 	if (!unpack_nameX(e, AA_STRUCT, "profile"))
635 		goto fail;
636 	if (!unpack_str(e, &name, NULL))
637 		goto fail;
638 	if (*name == '\0')
639 		goto fail;
640 
641 	tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
642 	if (tmpns) {
643 		*ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
644 		if (!*ns_name) {
645 			info = "out of memory";
646 			goto fail;
647 		}
648 		name = tmpname;
649 	}
650 
651 	profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
652 	if (!profile)
653 		return ERR_PTR(-ENOMEM);
654 
655 	/* profile renaming is optional */
656 	(void) unpack_str(e, &profile->rename, "rename");
657 
658 	/* attachment string is optional */
659 	(void) unpack_str(e, &profile->attach, "attach");
660 
661 	/* xmatch is optional and may be NULL */
662 	profile->xmatch = unpack_dfa(e);
663 	if (IS_ERR(profile->xmatch)) {
664 		error = PTR_ERR(profile->xmatch);
665 		profile->xmatch = NULL;
666 		info = "bad xmatch";
667 		goto fail;
668 	}
669 	/* xmatch_len is not optional if xmatch is set */
670 	if (profile->xmatch) {
671 		if (!unpack_u32(e, &tmp, NULL)) {
672 			info = "missing xmatch len";
673 			goto fail;
674 		}
675 		profile->xmatch_len = tmp;
676 	}
677 
678 	/* disconnected attachment string is optional */
679 	(void) unpack_str(e, &profile->disconnected, "disconnected");
680 
681 	/* per profile debug flags (complain, audit) */
682 	if (!unpack_nameX(e, AA_STRUCT, "flags")) {
683 		info = "profile missing flags";
684 		goto fail;
685 	}
686 	info = "failed to unpack profile flags";
687 	if (!unpack_u32(e, &tmp, NULL))
688 		goto fail;
689 	if (tmp & PACKED_FLAG_HAT)
690 		profile->label.flags |= FLAG_HAT;
691 	if (!unpack_u32(e, &tmp, NULL))
692 		goto fail;
693 	if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
694 		profile->mode = APPARMOR_COMPLAIN;
695 	else if (tmp == PACKED_MODE_KILL)
696 		profile->mode = APPARMOR_KILL;
697 	else if (tmp == PACKED_MODE_UNCONFINED)
698 		profile->mode = APPARMOR_UNCONFINED;
699 	if (!unpack_u32(e, &tmp, NULL))
700 		goto fail;
701 	if (tmp)
702 		profile->audit = AUDIT_ALL;
703 
704 	if (!unpack_nameX(e, AA_STRUCTEND, NULL))
705 		goto fail;
706 
707 	/* path_flags is optional */
708 	if (unpack_u32(e, &profile->path_flags, "path_flags"))
709 		profile->path_flags |= profile->label.flags &
710 			PATH_MEDIATE_DELETED;
711 	else
712 		/* set a default value if path_flags field is not present */
713 		profile->path_flags = PATH_MEDIATE_DELETED;
714 
715 	info = "failed to unpack profile capabilities";
716 	if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
717 		goto fail;
718 	if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
719 		goto fail;
720 	if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
721 		goto fail;
722 	if (!unpack_u32(e, &tmpcap.cap[0], NULL))
723 		goto fail;
724 
725 	info = "failed to unpack upper profile capabilities";
726 	if (unpack_nameX(e, AA_STRUCT, "caps64")) {
727 		/* optional upper half of 64 bit caps */
728 		if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
729 			goto fail;
730 		if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
731 			goto fail;
732 		if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
733 			goto fail;
734 		if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
735 			goto fail;
736 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
737 			goto fail;
738 	}
739 
740 	info = "failed to unpack extended profile capabilities";
741 	if (unpack_nameX(e, AA_STRUCT, "capsx")) {
742 		/* optional extended caps mediation mask */
743 		if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
744 			goto fail;
745 		if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
746 			goto fail;
747 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
748 			goto fail;
749 	}
750 
751 	if (!unpack_xattrs(e, profile)) {
752 		info = "failed to unpack profile xattrs";
753 		goto fail;
754 	}
755 
756 	if (!unpack_rlimits(e, profile)) {
757 		info = "failed to unpack profile rlimits";
758 		goto fail;
759 	}
760 
761 	if (unpack_nameX(e, AA_STRUCT, "policydb")) {
762 		/* generic policy dfa - optional and may be NULL */
763 		info = "failed to unpack policydb";
764 		profile->policy.dfa = unpack_dfa(e);
765 		if (IS_ERR(profile->policy.dfa)) {
766 			error = PTR_ERR(profile->policy.dfa);
767 			profile->policy.dfa = NULL;
768 			goto fail;
769 		} else if (!profile->policy.dfa) {
770 			error = -EPROTO;
771 			goto fail;
772 		}
773 		if (!unpack_u32(e, &profile->policy.start[0], "start"))
774 			/* default start state */
775 			profile->policy.start[0] = DFA_START;
776 		/* setup class index */
777 		for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
778 			profile->policy.start[i] =
779 				aa_dfa_next(profile->policy.dfa,
780 					    profile->policy.start[0],
781 					    i);
782 		}
783 		if (!unpack_nameX(e, AA_STRUCTEND, NULL))
784 			goto fail;
785 	} else
786 		profile->policy.dfa = aa_get_dfa(nulldfa);
787 
788 	/* get file rules */
789 	profile->file.dfa = unpack_dfa(e);
790 	if (IS_ERR(profile->file.dfa)) {
791 		error = PTR_ERR(profile->file.dfa);
792 		profile->file.dfa = NULL;
793 		info = "failed to unpack profile file rules";
794 		goto fail;
795 	} else if (profile->file.dfa) {
796 		if (!unpack_u32(e, &profile->file.start, "dfa_start"))
797 			/* default start state */
798 			profile->file.start = DFA_START;
799 	} else if (profile->policy.dfa &&
800 		   profile->policy.start[AA_CLASS_FILE]) {
801 		profile->file.dfa = aa_get_dfa(profile->policy.dfa);
802 		profile->file.start = profile->policy.start[AA_CLASS_FILE];
803 	} else
804 		profile->file.dfa = aa_get_dfa(nulldfa);
805 
806 	if (!unpack_trans_table(e, profile)) {
807 		info = "failed to unpack profile transition table";
808 		goto fail;
809 	}
810 
811 	if (unpack_nameX(e, AA_STRUCT, "data")) {
812 		info = "out of memory";
813 		profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
814 		if (!profile->data)
815 			goto fail;
816 
817 		params.nelem_hint = 3;
818 		params.key_len = sizeof(void *);
819 		params.key_offset = offsetof(struct aa_data, key);
820 		params.head_offset = offsetof(struct aa_data, head);
821 		params.hashfn = strhash;
822 		params.obj_cmpfn = datacmp;
823 
824 		if (rhashtable_init(profile->data, &params)) {
825 			info = "failed to init key, value hash table";
826 			goto fail;
827 		}
828 
829 		while (unpack_strdup(e, &key, NULL)) {
830 			data = kzalloc(sizeof(*data), GFP_KERNEL);
831 			if (!data) {
832 				kzfree(key);
833 				goto fail;
834 			}
835 
836 			data->key = key;
837 			data->size = unpack_blob(e, &data->data, NULL);
838 			data->data = kvmemdup(data->data, data->size);
839 			if (data->size && !data->data) {
840 				kzfree(data->key);
841 				kzfree(data);
842 				goto fail;
843 			}
844 
845 			rhashtable_insert_fast(profile->data, &data->head,
846 					       profile->data->p);
847 		}
848 
849 		if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
850 			info = "failed to unpack end of key, value data table";
851 			goto fail;
852 		}
853 	}
854 
855 	if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
856 		info = "failed to unpack end of profile";
857 		goto fail;
858 	}
859 
860 	return profile;
861 
862 fail:
863 	if (profile)
864 		name = NULL;
865 	else if (!name)
866 		name = "unknown";
867 	audit_iface(profile, NULL, name, info, e, error);
868 	aa_free_profile(profile);
869 
870 	return ERR_PTR(error);
871 }
872 
873 /**
874  * verify_head - unpack serialized stream header
875  * @e: serialized data read head (NOT NULL)
876  * @required: whether the header is required or optional
877  * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
878  *
879  * Returns: error or 0 if header is good
880  */
881 static int verify_header(struct aa_ext *e, int required, const char **ns)
882 {
883 	int error = -EPROTONOSUPPORT;
884 	const char *name = NULL;
885 	*ns = NULL;
886 
887 	/* get the interface version */
888 	if (!unpack_u32(e, &e->version, "version")) {
889 		if (required) {
890 			audit_iface(NULL, NULL, NULL, "invalid profile format",
891 				    e, error);
892 			return error;
893 		}
894 	}
895 
896 	/* Check that the interface version is currently supported.
897 	 * if not specified use previous version
898 	 * Mask off everything that is not kernel abi version
899 	 */
900 	if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
901 		audit_iface(NULL, NULL, NULL, "unsupported interface version",
902 			    e, error);
903 		return error;
904 	}
905 
906 	/* read the namespace if present */
907 	if (unpack_str(e, &name, "namespace")) {
908 		if (*name == '\0') {
909 			audit_iface(NULL, NULL, NULL, "invalid namespace name",
910 				    e, error);
911 			return error;
912 		}
913 		if (*ns && strcmp(*ns, name))
914 			audit_iface(NULL, NULL, NULL, "invalid ns change", e,
915 				    error);
916 		else if (!*ns)
917 			*ns = name;
918 	}
919 
920 	return 0;
921 }
922 
923 static bool verify_xindex(int xindex, int table_size)
924 {
925 	int index, xtype;
926 	xtype = xindex & AA_X_TYPE_MASK;
927 	index = xindex & AA_X_INDEX_MASK;
928 	if (xtype == AA_X_TABLE && index >= table_size)
929 		return 0;
930 	return 1;
931 }
932 
933 /* verify dfa xindexes are in range of transition tables */
934 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
935 {
936 	int i;
937 	for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
938 		if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
939 			return 0;
940 		if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
941 			return 0;
942 	}
943 	return 1;
944 }
945 
946 /**
947  * verify_profile - Do post unpack analysis to verify profile consistency
948  * @profile: profile to verify (NOT NULL)
949  *
950  * Returns: 0 if passes verification else error
951  */
952 static int verify_profile(struct aa_profile *profile)
953 {
954 	if (profile->file.dfa &&
955 	    !verify_dfa_xindex(profile->file.dfa,
956 			       profile->file.trans.size)) {
957 		audit_iface(profile, NULL, NULL, "Invalid named transition",
958 			    NULL, -EPROTO);
959 		return -EPROTO;
960 	}
961 
962 	return 0;
963 }
964 
965 void aa_load_ent_free(struct aa_load_ent *ent)
966 {
967 	if (ent) {
968 		aa_put_profile(ent->rename);
969 		aa_put_profile(ent->old);
970 		aa_put_profile(ent->new);
971 		kfree(ent->ns_name);
972 		kzfree(ent);
973 	}
974 }
975 
976 struct aa_load_ent *aa_load_ent_alloc(void)
977 {
978 	struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
979 	if (ent)
980 		INIT_LIST_HEAD(&ent->list);
981 	return ent;
982 }
983 
984 /**
985  * aa_unpack - unpack packed binary profile(s) data loaded from user space
986  * @udata: user data copied to kmem  (NOT NULL)
987  * @lh: list to place unpacked profiles in a aa_repl_ws
988  * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
989  *
990  * Unpack user data and return refcounted allocated profile(s) stored in
991  * @lh in order of discovery, with the list chain stored in base.list
992  * or error
993  *
994  * Returns: profile(s) on @lh else error pointer if fails to unpack
995  */
996 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
997 	      const char **ns)
998 {
999 	struct aa_load_ent *tmp, *ent;
1000 	struct aa_profile *profile = NULL;
1001 	int error;
1002 	struct aa_ext e = {
1003 		.start = udata->data,
1004 		.end = udata->data + udata->size,
1005 		.pos = udata->data,
1006 	};
1007 
1008 	*ns = NULL;
1009 	while (e.pos < e.end) {
1010 		char *ns_name = NULL;
1011 		void *start;
1012 		error = verify_header(&e, e.pos == e.start, ns);
1013 		if (error)
1014 			goto fail;
1015 
1016 		start = e.pos;
1017 		profile = unpack_profile(&e, &ns_name);
1018 		if (IS_ERR(profile)) {
1019 			error = PTR_ERR(profile);
1020 			goto fail;
1021 		}
1022 
1023 		error = verify_profile(profile);
1024 		if (error)
1025 			goto fail_profile;
1026 
1027 		if (aa_g_hash_policy)
1028 			error = aa_calc_profile_hash(profile, e.version, start,
1029 						     e.pos - start);
1030 		if (error)
1031 			goto fail_profile;
1032 
1033 		ent = aa_load_ent_alloc();
1034 		if (!ent) {
1035 			error = -ENOMEM;
1036 			goto fail_profile;
1037 		}
1038 
1039 		ent->new = profile;
1040 		ent->ns_name = ns_name;
1041 		list_add_tail(&ent->list, lh);
1042 	}
1043 	udata->abi = e.version & K_ABI_MASK;
1044 	if (aa_g_hash_policy) {
1045 		udata->hash = aa_calc_hash(udata->data, udata->size);
1046 		if (IS_ERR(udata->hash)) {
1047 			error = PTR_ERR(udata->hash);
1048 			udata->hash = NULL;
1049 			goto fail;
1050 		}
1051 	}
1052 	return 0;
1053 
1054 fail_profile:
1055 	aa_put_profile(profile);
1056 
1057 fail:
1058 	list_for_each_entry_safe(ent, tmp, lh, list) {
1059 		list_del_init(&ent->list);
1060 		aa_load_ent_free(ent);
1061 	}
1062 
1063 	return error;
1064 }
1065