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1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor functions for unpacking policy loaded from
5 * userspace.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation, version 2 of the
13 * License.
14 *
15 * AppArmor uses a serialized binary format for loading policy. To find
16 * policy format documentation look in Documentation/security/apparmor.txt
17 * All policy is validated before it is used.
18 */
19
20#include <asm/unaligned.h>
21#include <linux/ctype.h>
22#include <linux/errno.h>
23
24#include "include/apparmor.h"
25#include "include/audit.h"
26#include "include/context.h"
27#include "include/crypto.h"
28#include "include/match.h"
29#include "include/policy.h"
30#include "include/policy_unpack.h"
31
32/*
33 * The AppArmor interface treats data as a type byte followed by the
34 * actual data. The interface has the notion of a a named entry
35 * which has a name (AA_NAME typecode followed by name string) followed by
36 * the entries typecode and data. Named types allow for optional
37 * elements and extensions to be added and tested for without breaking
38 * backwards compatibility.
39 */
40
41enum aa_code {
42 AA_U8,
43 AA_U16,
44 AA_U32,
45 AA_U64,
46 AA_NAME, /* same as string except it is items name */
47 AA_STRING,
48 AA_BLOB,
49 AA_STRUCT,
50 AA_STRUCTEND,
51 AA_LIST,
52 AA_LISTEND,
53 AA_ARRAY,
54 AA_ARRAYEND,
55};
56
57/*
58 * aa_ext is the read of the buffer containing the serialized profile. The
59 * data is copied into a kernel buffer in apparmorfs and then handed off to
60 * the unpack routines.
61 */
62struct aa_ext {
63 void *start;
64 void *end;
65 void *pos; /* pointer to current position in the buffer */
66 u32 version;
67};
68
69/* audit callback for unpack fields */
70static void audit_cb(struct audit_buffer *ab, void *va)
71{
72 struct common_audit_data *sa = va;
73 if (sa->aad->iface.target) {
74 struct aa_profile *name = sa->aad->iface.target;
75 audit_log_format(ab, " name=");
76 audit_log_untrustedstring(ab, name->base.hname);
77 }
78 if (sa->aad->iface.pos)
79 audit_log_format(ab, " offset=%ld", sa->aad->iface.pos);
80}
81
82/**
83 * audit_iface - do audit message for policy unpacking/load/replace/remove
84 * @new: profile if it has been allocated (MAYBE NULL)
85 * @name: name of the profile being manipulated (MAYBE NULL)
86 * @info: any extra info about the failure (MAYBE NULL)
87 * @e: buffer position info
88 * @error: error code
89 *
90 * Returns: %0 or error
91 */
92static int audit_iface(struct aa_profile *new, const char *name,
93 const char *info, struct aa_ext *e, int error)
94{
95 struct aa_profile *profile = __aa_current_profile();
96 struct common_audit_data sa;
97 struct apparmor_audit_data aad = {0,};
98 sa.type = LSM_AUDIT_DATA_NONE;
99 sa.aad = &aad;
100 if (e)
101 aad.iface.pos = e->pos - e->start;
102 aad.iface.target = new;
103 aad.name = name;
104 aad.info = info;
105 aad.error = error;
106
107 return aa_audit(AUDIT_APPARMOR_STATUS, profile, GFP_KERNEL, &sa,
108 audit_cb);
109}
110
111/* test if read will be in packed data bounds */
112static bool inbounds(struct aa_ext *e, size_t size)
113{
114 return (size <= e->end - e->pos);
115}
116
117/**
118 * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
119 * @e: serialized data read head (NOT NULL)
120 * @chunk: start address for chunk of data (NOT NULL)
121 *
122 * Returns: the size of chunk found with the read head at the end of the chunk.
123 */
124static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
125{
126 size_t size = 0;
127
128 if (!inbounds(e, sizeof(u16)))
129 return 0;
130 size = le16_to_cpu(get_unaligned((u16 *) e->pos));
131 e->pos += sizeof(u16);
132 if (!inbounds(e, size))
133 return 0;
134 *chunk = e->pos;
135 e->pos += size;
136 return size;
137}
138
139/* unpack control byte */
140static bool unpack_X(struct aa_ext *e, enum aa_code code)
141{
142 if (!inbounds(e, 1))
143 return 0;
144 if (*(u8 *) e->pos != code)
145 return 0;
146 e->pos++;
147 return 1;
148}
149
150/**
151 * unpack_nameX - check is the next element is of type X with a name of @name
152 * @e: serialized data extent information (NOT NULL)
153 * @code: type code
154 * @name: name to match to the serialized element. (MAYBE NULL)
155 *
156 * check that the next serialized data element is of type X and has a tag
157 * name @name. If @name is specified then there must be a matching
158 * name element in the stream. If @name is NULL any name element will be
159 * skipped and only the typecode will be tested.
160 *
161 * Returns 1 on success (both type code and name tests match) and the read
162 * head is advanced past the headers
163 *
164 * Returns: 0 if either match fails, the read head does not move
165 */
166static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
167{
168 /*
169 * May need to reset pos if name or type doesn't match
170 */
171 void *pos = e->pos;
172 /*
173 * Check for presence of a tagname, and if present name size
174 * AA_NAME tag value is a u16.
175 */
176 if (unpack_X(e, AA_NAME)) {
177 char *tag = NULL;
178 size_t size = unpack_u16_chunk(e, &tag);
179 /* if a name is specified it must match. otherwise skip tag */
180 if (name && (!size || strcmp(name, tag)))
181 goto fail;
182 } else if (name) {
183 /* if a name is specified and there is no name tag fail */
184 goto fail;
185 }
186
187 /* now check if type code matches */
188 if (unpack_X(e, code))
189 return 1;
190
191fail:
192 e->pos = pos;
193 return 0;
194}
195
196static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
197{
198 if (unpack_nameX(e, AA_U32, name)) {
199 if (!inbounds(e, sizeof(u32)))
200 return 0;
201 if (data)
202 *data = le32_to_cpu(get_unaligned((u32 *) e->pos));
203 e->pos += sizeof(u32);
204 return 1;
205 }
206 return 0;
207}
208
209static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
210{
211 if (unpack_nameX(e, AA_U64, name)) {
212 if (!inbounds(e, sizeof(u64)))
213 return 0;
214 if (data)
215 *data = le64_to_cpu(get_unaligned((u64 *) e->pos));
216 e->pos += sizeof(u64);
217 return 1;
218 }
219 return 0;
220}
221
222static size_t unpack_array(struct aa_ext *e, const char *name)
223{
224 if (unpack_nameX(e, AA_ARRAY, name)) {
225 int size;
226 if (!inbounds(e, sizeof(u16)))
227 return 0;
228 size = (int)le16_to_cpu(get_unaligned((u16 *) e->pos));
229 e->pos += sizeof(u16);
230 return size;
231 }
232 return 0;
233}
234
235static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
236{
237 if (unpack_nameX(e, AA_BLOB, name)) {
238 u32 size;
239 if (!inbounds(e, sizeof(u32)))
240 return 0;
241 size = le32_to_cpu(get_unaligned((u32 *) e->pos));
242 e->pos += sizeof(u32);
243 if (inbounds(e, (size_t) size)) {
244 *blob = e->pos;
245 e->pos += size;
246 return size;
247 }
248 }
249 return 0;
250}
251
252static int unpack_str(struct aa_ext *e, const char **string, const char *name)
253{
254 char *src_str;
255 size_t size = 0;
256 void *pos = e->pos;
257 *string = NULL;
258 if (unpack_nameX(e, AA_STRING, name)) {
259 size = unpack_u16_chunk(e, &src_str);
260 if (size) {
261 /* strings are null terminated, length is size - 1 */
262 if (src_str[size - 1] != 0)
263 goto fail;
264 *string = src_str;
265 }
266 }
267 return size;
268
269fail:
270 e->pos = pos;
271 return 0;
272}
273
274static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
275{
276 const char *tmp;
277 void *pos = e->pos;
278 int res = unpack_str(e, &tmp, name);
279 *string = NULL;
280
281 if (!res)
282 return 0;
283
284 *string = kmemdup(tmp, res, GFP_KERNEL);
285 if (!*string) {
286 e->pos = pos;
287 return 0;
288 }
289
290 return res;
291}
292
293#define DFA_VALID_PERM_MASK 0xffffffff
294#define DFA_VALID_PERM2_MASK 0xffffffff
295
296/**
297 * verify_accept - verify the accept tables of a dfa
298 * @dfa: dfa to verify accept tables of (NOT NULL)
299 * @flags: flags governing dfa
300 *
301 * Returns: 1 if valid accept tables else 0 if error
302 */
303static bool verify_accept(struct aa_dfa *dfa, int flags)
304{
305 int i;
306
307 /* verify accept permissions */
308 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
309 int mode = ACCEPT_TABLE(dfa)[i];
310
311 if (mode & ~DFA_VALID_PERM_MASK)
312 return 0;
313
314 if (ACCEPT_TABLE2(dfa)[i] & ~DFA_VALID_PERM2_MASK)
315 return 0;
316 }
317 return 1;
318}
319
320/**
321 * unpack_dfa - unpack a file rule dfa
322 * @e: serialized data extent information (NOT NULL)
323 *
324 * returns dfa or ERR_PTR or NULL if no dfa
325 */
326static struct aa_dfa *unpack_dfa(struct aa_ext *e)
327{
328 char *blob = NULL;
329 size_t size;
330 struct aa_dfa *dfa = NULL;
331
332 size = unpack_blob(e, &blob, "aadfa");
333 if (size) {
334 /*
335 * The dfa is aligned with in the blob to 8 bytes
336 * from the beginning of the stream.
337 * alignment adjust needed by dfa unpack
338 */
339 size_t sz = blob - (char *) e->start -
340 ((e->pos - e->start) & 7);
341 size_t pad = ALIGN(sz, 8) - sz;
342 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
343 TO_ACCEPT2_FLAG(YYTD_DATA32);
344
345
346 if (aa_g_paranoid_load)
347 flags |= DFA_FLAG_VERIFY_STATES;
348
349 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
350
351 if (IS_ERR(dfa))
352 return dfa;
353
354 if (!verify_accept(dfa, flags))
355 goto fail;
356 }
357
358 return dfa;
359
360fail:
361 aa_put_dfa(dfa);
362 return ERR_PTR(-EPROTO);
363}
364
365/**
366 * unpack_trans_table - unpack a profile transition table
367 * @e: serialized data extent information (NOT NULL)
368 * @profile: profile to add the accept table to (NOT NULL)
369 *
370 * Returns: 1 if table successfully unpacked
371 */
372static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
373{
374 void *pos = e->pos;
375
376 /* exec table is optional */
377 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
378 int i, size;
379
380 size = unpack_array(e, NULL);
381 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
382 if (size > 16 - 4)
383 goto fail;
384 profile->file.trans.table = kzalloc(sizeof(char *) * size,
385 GFP_KERNEL);
386 if (!profile->file.trans.table)
387 goto fail;
388
389 profile->file.trans.size = size;
390 for (i = 0; i < size; i++) {
391 char *str;
392 int c, j, size2 = unpack_strdup(e, &str, NULL);
393 /* unpack_strdup verifies that the last character is
394 * null termination byte.
395 */
396 if (!size2)
397 goto fail;
398 profile->file.trans.table[i] = str;
399 /* verify that name doesn't start with space */
400 if (isspace(*str))
401 goto fail;
402
403 /* count internal # of internal \0 */
404 for (c = j = 0; j < size2 - 2; j++) {
405 if (!str[j])
406 c++;
407 }
408 if (*str == ':') {
409 /* beginning with : requires an embedded \0,
410 * verify that exactly 1 internal \0 exists
411 * trailing \0 already verified by unpack_strdup
412 */
413 if (c != 1)
414 goto fail;
415 /* first character after : must be valid */
416 if (!str[1])
417 goto fail;
418 } else if (c)
419 /* fail - all other cases with embedded \0 */
420 goto fail;
421 }
422 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
423 goto fail;
424 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
425 goto fail;
426 }
427 return 1;
428
429fail:
430 aa_free_domain_entries(&profile->file.trans);
431 e->pos = pos;
432 return 0;
433}
434
435static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
436{
437 void *pos = e->pos;
438
439 /* rlimits are optional */
440 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
441 int i, size;
442 u32 tmp = 0;
443 if (!unpack_u32(e, &tmp, NULL))
444 goto fail;
445 profile->rlimits.mask = tmp;
446
447 size = unpack_array(e, NULL);
448 if (size > RLIM_NLIMITS)
449 goto fail;
450 for (i = 0; i < size; i++) {
451 u64 tmp2 = 0;
452 int a = aa_map_resource(i);
453 if (!unpack_u64(e, &tmp2, NULL))
454 goto fail;
455 profile->rlimits.limits[a].rlim_max = tmp2;
456 }
457 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
458 goto fail;
459 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
460 goto fail;
461 }
462 return 1;
463
464fail:
465 e->pos = pos;
466 return 0;
467}
468
469/**
470 * unpack_profile - unpack a serialized profile
471 * @e: serialized data extent information (NOT NULL)
472 *
473 * NOTE: unpack profile sets audit struct if there is a failure
474 */
475static struct aa_profile *unpack_profile(struct aa_ext *e)
476{
477 struct aa_profile *profile = NULL;
478 const char *name = NULL;
479 int i, error = -EPROTO;
480 kernel_cap_t tmpcap;
481 u32 tmp;
482
483 /* check that we have the right struct being passed */
484 if (!unpack_nameX(e, AA_STRUCT, "profile"))
485 goto fail;
486 if (!unpack_str(e, &name, NULL))
487 goto fail;
488
489 profile = aa_alloc_profile(name);
490 if (!profile)
491 return ERR_PTR(-ENOMEM);
492
493 /* profile renaming is optional */
494 (void) unpack_str(e, &profile->rename, "rename");
495
496 /* attachment string is optional */
497 (void) unpack_str(e, &profile->attach, "attach");
498
499 /* xmatch is optional and may be NULL */
500 profile->xmatch = unpack_dfa(e);
501 if (IS_ERR(profile->xmatch)) {
502 error = PTR_ERR(profile->xmatch);
503 profile->xmatch = NULL;
504 goto fail;
505 }
506 /* xmatch_len is not optional if xmatch is set */
507 if (profile->xmatch) {
508 if (!unpack_u32(e, &tmp, NULL))
509 goto fail;
510 profile->xmatch_len = tmp;
511 }
512
513 /* per profile debug flags (complain, audit) */
514 if (!unpack_nameX(e, AA_STRUCT, "flags"))
515 goto fail;
516 if (!unpack_u32(e, &tmp, NULL))
517 goto fail;
518 if (tmp & PACKED_FLAG_HAT)
519 profile->flags |= PFLAG_HAT;
520 if (!unpack_u32(e, &tmp, NULL))
521 goto fail;
522 if (tmp == PACKED_MODE_COMPLAIN)
523 profile->mode = APPARMOR_COMPLAIN;
524 else if (tmp == PACKED_MODE_KILL)
525 profile->mode = APPARMOR_KILL;
526 else if (tmp == PACKED_MODE_UNCONFINED)
527 profile->mode = APPARMOR_UNCONFINED;
528 if (!unpack_u32(e, &tmp, NULL))
529 goto fail;
530 if (tmp)
531 profile->audit = AUDIT_ALL;
532
533 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
534 goto fail;
535
536 /* path_flags is optional */
537 if (unpack_u32(e, &profile->path_flags, "path_flags"))
538 profile->path_flags |= profile->flags & PFLAG_MEDIATE_DELETED;
539 else
540 /* set a default value if path_flags field is not present */
541 profile->path_flags = PFLAG_MEDIATE_DELETED;
542
543 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
544 goto fail;
545 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
546 goto fail;
547 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
548 goto fail;
549 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
550 goto fail;
551
552 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
553 /* optional upper half of 64 bit caps */
554 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
555 goto fail;
556 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
557 goto fail;
558 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
559 goto fail;
560 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
561 goto fail;
562 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
563 goto fail;
564 }
565
566 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
567 /* optional extended caps mediation mask */
568 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
569 goto fail;
570 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
571 goto fail;
572 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
573 goto fail;
574 }
575
576 if (!unpack_rlimits(e, profile))
577 goto fail;
578
579 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
580 /* generic policy dfa - optional and may be NULL */
581 profile->policy.dfa = unpack_dfa(e);
582 if (IS_ERR(profile->policy.dfa)) {
583 error = PTR_ERR(profile->policy.dfa);
584 profile->policy.dfa = NULL;
585 goto fail;
586 }
587 if (!unpack_u32(e, &profile->policy.start[0], "start"))
588 /* default start state */
589 profile->policy.start[0] = DFA_START;
590 /* setup class index */
591 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
592 profile->policy.start[i] =
593 aa_dfa_next(profile->policy.dfa,
594 profile->policy.start[0],
595 i);
596 }
597 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
598 goto fail;
599 }
600
601 /* get file rules */
602 profile->file.dfa = unpack_dfa(e);
603 if (IS_ERR(profile->file.dfa)) {
604 error = PTR_ERR(profile->file.dfa);
605 profile->file.dfa = NULL;
606 goto fail;
607 }
608
609 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
610 /* default start state */
611 profile->file.start = DFA_START;
612
613 if (!unpack_trans_table(e, profile))
614 goto fail;
615
616 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
617 goto fail;
618
619 return profile;
620
621fail:
622 if (profile)
623 name = NULL;
624 else if (!name)
625 name = "unknown";
626 audit_iface(profile, name, "failed to unpack profile", e, error);
627 aa_free_profile(profile);
628
629 return ERR_PTR(error);
630}
631
632/**
633 * verify_head - unpack serialized stream header
634 * @e: serialized data read head (NOT NULL)
635 * @required: whether the header is required or optional
636 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
637 *
638 * Returns: error or 0 if header is good
639 */
640static int verify_header(struct aa_ext *e, int required, const char **ns)
641{
642 int error = -EPROTONOSUPPORT;
643 const char *name = NULL;
644 *ns = NULL;
645
646 /* get the interface version */
647 if (!unpack_u32(e, &e->version, "version")) {
648 if (required) {
649 audit_iface(NULL, NULL, "invalid profile format", e,
650 error);
651 return error;
652 }
653
654 /* check that the interface version is currently supported */
655 if (e->version != 5) {
656 audit_iface(NULL, NULL, "unsupported interface version",
657 e, error);
658 return error;
659 }
660 }
661
662
663 /* read the namespace if present */
664 if (unpack_str(e, &name, "namespace")) {
665 if (*ns && strcmp(*ns, name))
666 audit_iface(NULL, NULL, "invalid ns change", e, error);
667 else if (!*ns)
668 *ns = name;
669 }
670
671 return 0;
672}
673
674static bool verify_xindex(int xindex, int table_size)
675{
676 int index, xtype;
677 xtype = xindex & AA_X_TYPE_MASK;
678 index = xindex & AA_X_INDEX_MASK;
679 if (xtype == AA_X_TABLE && index > table_size)
680 return 0;
681 return 1;
682}
683
684/* verify dfa xindexes are in range of transition tables */
685static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
686{
687 int i;
688 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
689 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
690 return 0;
691 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
692 return 0;
693 }
694 return 1;
695}
696
697/**
698 * verify_profile - Do post unpack analysis to verify profile consistency
699 * @profile: profile to verify (NOT NULL)
700 *
701 * Returns: 0 if passes verification else error
702 */
703static int verify_profile(struct aa_profile *profile)
704{
705 if (aa_g_paranoid_load) {
706 if (profile->file.dfa &&
707 !verify_dfa_xindex(profile->file.dfa,
708 profile->file.trans.size)) {
709 audit_iface(profile, NULL, "Invalid named transition",
710 NULL, -EPROTO);
711 return -EPROTO;
712 }
713 }
714
715 return 0;
716}
717
718void aa_load_ent_free(struct aa_load_ent *ent)
719{
720 if (ent) {
721 aa_put_profile(ent->rename);
722 aa_put_profile(ent->old);
723 aa_put_profile(ent->new);
724 kzfree(ent);
725 }
726}
727
728struct aa_load_ent *aa_load_ent_alloc(void)
729{
730 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
731 if (ent)
732 INIT_LIST_HEAD(&ent->list);
733 return ent;
734}
735
736/**
737 * aa_unpack - unpack packed binary profile(s) data loaded from user space
738 * @udata: user data copied to kmem (NOT NULL)
739 * @size: the size of the user data
740 * @lh: list to place unpacked profiles in a aa_repl_ws
741 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
742 *
743 * Unpack user data and return refcounted allocated profile(s) stored in
744 * @lh in order of discovery, with the list chain stored in base.list
745 * or error
746 *
747 * Returns: profile(s) on @lh else error pointer if fails to unpack
748 */
749int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns)
750{
751 struct aa_load_ent *tmp, *ent;
752 struct aa_profile *profile = NULL;
753 int error;
754 struct aa_ext e = {
755 .start = udata,
756 .end = udata + size,
757 .pos = udata,
758 };
759
760 *ns = NULL;
761 while (e.pos < e.end) {
762 void *start;
763 error = verify_header(&e, e.pos == e.start, ns);
764 if (error)
765 goto fail;
766
767 start = e.pos;
768 profile = unpack_profile(&e);
769 if (IS_ERR(profile)) {
770 error = PTR_ERR(profile);
771 goto fail;
772 }
773
774 error = verify_profile(profile);
775 if (error)
776 goto fail_profile;
777
778 error = aa_calc_profile_hash(profile, e.version, start,
779 e.pos - start);
780 if (error)
781 goto fail_profile;
782
783 ent = aa_load_ent_alloc();
784 if (!ent) {
785 error = -ENOMEM;
786 goto fail_profile;
787 }
788
789 ent->new = profile;
790 list_add_tail(&ent->list, lh);
791 }
792
793 return 0;
794
795fail_profile:
796 aa_put_profile(profile);
797
798fail:
799 list_for_each_entry_safe(ent, tmp, lh, list) {
800 list_del_init(&ent->list);
801 aa_load_ent_free(ent);
802 }
803
804 return error;
805}
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor functions for unpacking policy loaded from
6 * userspace.
7 *
8 * Copyright (C) 1998-2008 Novell/SUSE
9 * Copyright 2009-2010 Canonical Ltd.
10 *
11 * AppArmor uses a serialized binary format for loading policy. To find
12 * policy format documentation see Documentation/admin-guide/LSM/apparmor.rst
13 * All policy is validated before it is used.
14 */
15
16#include <asm/unaligned.h>
17#include <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 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
49enum 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 */
70struct 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 */
78static 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 */
105static 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
124void __aa_loaddata_update(struct aa_loaddata *data, long revision)
125{
126 AA_BUG(!data);
127 AA_BUG(!data->ns);
128 AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
129 AA_BUG(!mutex_is_locked(&data->ns->lock));
130 AA_BUG(data->revision > revision);
131
132 data->revision = 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
139bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
140{
141 if (l->size != r->size)
142 return false;
143 if (l->compressed_size != r->compressed_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->compressed_size ?: 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 */
154static 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 kfree_sensitive(d->hash);
167 kfree_sensitive(d->name);
168 kvfree(d->data);
169 kfree_sensitive(d);
170}
171
172void 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
182struct 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 */
201static bool inbounds(struct aa_ext *e, size_t size)
202{
203 return (size <= e->end - e->pos);
204}
205
206static 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 */
222static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
223{
224 size_t size = 0;
225 void *pos = e->pos;
226
227 if (!inbounds(e, sizeof(u16)))
228 goto fail;
229 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
230 e->pos += sizeof(__le16);
231 if (!inbounds(e, size))
232 goto fail;
233 *chunk = e->pos;
234 e->pos += size;
235 return size;
236
237fail:
238 e->pos = pos;
239 return 0;
240}
241
242/* unpack control byte */
243static bool unpack_X(struct aa_ext *e, enum aa_code code)
244{
245 if (!inbounds(e, 1))
246 return false;
247 if (*(u8 *) e->pos != code)
248 return false;
249 e->pos++;
250 return true;
251}
252
253/**
254 * unpack_nameX - check is the next element is of type X with a name of @name
255 * @e: serialized data extent information (NOT NULL)
256 * @code: type code
257 * @name: name to match to the serialized element. (MAYBE NULL)
258 *
259 * check that the next serialized data element is of type X and has a tag
260 * name @name. If @name is specified then there must be a matching
261 * name element in the stream. If @name is NULL any name element will be
262 * skipped and only the typecode will be tested.
263 *
264 * Returns true on success (both type code and name tests match) and the read
265 * head is advanced past the headers
266 *
267 * Returns: false if either match fails, the read head does not move
268 */
269static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
270{
271 /*
272 * May need to reset pos if name or type doesn't match
273 */
274 void *pos = e->pos;
275 /*
276 * Check for presence of a tagname, and if present name size
277 * AA_NAME tag value is a u16.
278 */
279 if (unpack_X(e, AA_NAME)) {
280 char *tag = NULL;
281 size_t size = unpack_u16_chunk(e, &tag);
282 /* if a name is specified it must match. otherwise skip tag */
283 if (name && (!size || tag[size-1] != '\0' || strcmp(name, tag)))
284 goto fail;
285 } else if (name) {
286 /* if a name is specified and there is no name tag fail */
287 goto fail;
288 }
289
290 /* now check if type code matches */
291 if (unpack_X(e, code))
292 return true;
293
294fail:
295 e->pos = pos;
296 return false;
297}
298
299static bool unpack_u8(struct aa_ext *e, u8 *data, const char *name)
300{
301 void *pos = e->pos;
302
303 if (unpack_nameX(e, AA_U8, name)) {
304 if (!inbounds(e, sizeof(u8)))
305 goto fail;
306 if (data)
307 *data = get_unaligned((u8 *)e->pos);
308 e->pos += sizeof(u8);
309 return true;
310 }
311
312fail:
313 e->pos = pos;
314 return false;
315}
316
317static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
318{
319 void *pos = e->pos;
320
321 if (unpack_nameX(e, AA_U32, name)) {
322 if (!inbounds(e, sizeof(u32)))
323 goto fail;
324 if (data)
325 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
326 e->pos += sizeof(u32);
327 return true;
328 }
329
330fail:
331 e->pos = pos;
332 return false;
333}
334
335static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
336{
337 void *pos = e->pos;
338
339 if (unpack_nameX(e, AA_U64, name)) {
340 if (!inbounds(e, sizeof(u64)))
341 goto fail;
342 if (data)
343 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
344 e->pos += sizeof(u64);
345 return true;
346 }
347
348fail:
349 e->pos = pos;
350 return false;
351}
352
353static size_t unpack_array(struct aa_ext *e, const char *name)
354{
355 void *pos = e->pos;
356
357 if (unpack_nameX(e, AA_ARRAY, name)) {
358 int size;
359 if (!inbounds(e, sizeof(u16)))
360 goto fail;
361 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
362 e->pos += sizeof(u16);
363 return size;
364 }
365
366fail:
367 e->pos = pos;
368 return 0;
369}
370
371static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
372{
373 void *pos = e->pos;
374
375 if (unpack_nameX(e, AA_BLOB, name)) {
376 u32 size;
377 if (!inbounds(e, sizeof(u32)))
378 goto fail;
379 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
380 e->pos += sizeof(u32);
381 if (inbounds(e, (size_t) size)) {
382 *blob = e->pos;
383 e->pos += size;
384 return size;
385 }
386 }
387
388fail:
389 e->pos = pos;
390 return 0;
391}
392
393static int unpack_str(struct aa_ext *e, const char **string, const char *name)
394{
395 char *src_str;
396 size_t size = 0;
397 void *pos = e->pos;
398 *string = NULL;
399 if (unpack_nameX(e, AA_STRING, name)) {
400 size = unpack_u16_chunk(e, &src_str);
401 if (size) {
402 /* strings are null terminated, length is size - 1 */
403 if (src_str[size - 1] != 0)
404 goto fail;
405 *string = src_str;
406
407 return size;
408 }
409 }
410
411fail:
412 e->pos = pos;
413 return 0;
414}
415
416static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
417{
418 const char *tmp;
419 void *pos = e->pos;
420 int res = unpack_str(e, &tmp, name);
421 *string = NULL;
422
423 if (!res)
424 return 0;
425
426 *string = kmemdup(tmp, res, GFP_KERNEL);
427 if (!*string) {
428 e->pos = pos;
429 return 0;
430 }
431
432 return res;
433}
434
435
436/**
437 * unpack_dfa - unpack a file rule dfa
438 * @e: serialized data extent information (NOT NULL)
439 *
440 * returns dfa or ERR_PTR or NULL if no dfa
441 */
442static struct aa_dfa *unpack_dfa(struct aa_ext *e)
443{
444 char *blob = NULL;
445 size_t size;
446 struct aa_dfa *dfa = NULL;
447
448 size = unpack_blob(e, &blob, "aadfa");
449 if (size) {
450 /*
451 * The dfa is aligned with in the blob to 8 bytes
452 * from the beginning of the stream.
453 * alignment adjust needed by dfa unpack
454 */
455 size_t sz = blob - (char *) e->start -
456 ((e->pos - e->start) & 7);
457 size_t pad = ALIGN(sz, 8) - sz;
458 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
459 TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
460 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
461
462 if (IS_ERR(dfa))
463 return dfa;
464
465 }
466
467 return dfa;
468}
469
470/**
471 * unpack_trans_table - unpack a profile transition table
472 * @e: serialized data extent information (NOT NULL)
473 * @profile: profile to add the accept table to (NOT NULL)
474 *
475 * Returns: true if table successfully unpacked
476 */
477static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
478{
479 void *saved_pos = e->pos;
480
481 /* exec table is optional */
482 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
483 int i, size;
484
485 size = unpack_array(e, NULL);
486 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
487 if (size > 16 - 4)
488 goto fail;
489 profile->file.trans.table = kcalloc(size, sizeof(char *),
490 GFP_KERNEL);
491 if (!profile->file.trans.table)
492 goto fail;
493
494 profile->file.trans.size = size;
495 for (i = 0; i < size; i++) {
496 char *str;
497 int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
498 /* unpack_strdup verifies that the last character is
499 * null termination byte.
500 */
501 if (!size2)
502 goto fail;
503 profile->file.trans.table[i] = str;
504 /* verify that name doesn't start with space */
505 if (isspace(*str))
506 goto fail;
507
508 /* count internal # of internal \0 */
509 for (c = j = 0; j < size2 - 1; j++) {
510 if (!str[j]) {
511 pos = j;
512 c++;
513 }
514 }
515 if (*str == ':') {
516 /* first character after : must be valid */
517 if (!str[1])
518 goto fail;
519 /* beginning with : requires an embedded \0,
520 * verify that exactly 1 internal \0 exists
521 * trailing \0 already verified by unpack_strdup
522 *
523 * convert \0 back to : for label_parse
524 */
525 if (c == 1)
526 str[pos] = ':';
527 else if (c > 1)
528 goto fail;
529 } else if (c)
530 /* fail - all other cases with embedded \0 */
531 goto fail;
532 }
533 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
534 goto fail;
535 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
536 goto fail;
537 }
538 return true;
539
540fail:
541 aa_free_domain_entries(&profile->file.trans);
542 e->pos = saved_pos;
543 return false;
544}
545
546static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
547{
548 void *pos = e->pos;
549
550 if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
551 int i, size;
552
553 size = unpack_array(e, NULL);
554 profile->xattr_count = size;
555 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
556 if (!profile->xattrs)
557 goto fail;
558 for (i = 0; i < size; i++) {
559 if (!unpack_strdup(e, &profile->xattrs[i], NULL))
560 goto fail;
561 }
562 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
563 goto fail;
564 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
565 goto fail;
566 }
567
568 return true;
569
570fail:
571 e->pos = pos;
572 return false;
573}
574
575static bool unpack_secmark(struct aa_ext *e, struct aa_profile *profile)
576{
577 void *pos = e->pos;
578 int i, size;
579
580 if (unpack_nameX(e, AA_STRUCT, "secmark")) {
581 size = unpack_array(e, NULL);
582
583 profile->secmark = kcalloc(size, sizeof(struct aa_secmark),
584 GFP_KERNEL);
585 if (!profile->secmark)
586 goto fail;
587
588 profile->secmark_count = size;
589
590 for (i = 0; i < size; i++) {
591 if (!unpack_u8(e, &profile->secmark[i].audit, NULL))
592 goto fail;
593 if (!unpack_u8(e, &profile->secmark[i].deny, NULL))
594 goto fail;
595 if (!unpack_strdup(e, &profile->secmark[i].label, NULL))
596 goto fail;
597 }
598 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
599 goto fail;
600 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
601 goto fail;
602 }
603
604 return true;
605
606fail:
607 if (profile->secmark) {
608 for (i = 0; i < size; i++)
609 kfree(profile->secmark[i].label);
610 kfree(profile->secmark);
611 profile->secmark_count = 0;
612 profile->secmark = NULL;
613 }
614
615 e->pos = pos;
616 return false;
617}
618
619static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
620{
621 void *pos = e->pos;
622
623 /* rlimits are optional */
624 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
625 int i, size;
626 u32 tmp = 0;
627 if (!unpack_u32(e, &tmp, NULL))
628 goto fail;
629 profile->rlimits.mask = tmp;
630
631 size = unpack_array(e, NULL);
632 if (size > RLIM_NLIMITS)
633 goto fail;
634 for (i = 0; i < size; i++) {
635 u64 tmp2 = 0;
636 int a = aa_map_resource(i);
637 if (!unpack_u64(e, &tmp2, NULL))
638 goto fail;
639 profile->rlimits.limits[a].rlim_max = tmp2;
640 }
641 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
642 goto fail;
643 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
644 goto fail;
645 }
646 return true;
647
648fail:
649 e->pos = pos;
650 return false;
651}
652
653static u32 strhash(const void *data, u32 len, u32 seed)
654{
655 const char * const *key = data;
656
657 return jhash(*key, strlen(*key), seed);
658}
659
660static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
661{
662 const struct aa_data *data = obj;
663 const char * const *key = arg->key;
664
665 return strcmp(data->key, *key);
666}
667
668/**
669 * unpack_profile - unpack a serialized profile
670 * @e: serialized data extent information (NOT NULL)
671 *
672 * NOTE: unpack profile sets audit struct if there is a failure
673 */
674static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
675{
676 struct aa_profile *profile = NULL;
677 const char *tmpname, *tmpns = NULL, *name = NULL;
678 const char *info = "failed to unpack profile";
679 size_t ns_len;
680 struct rhashtable_params params = { 0 };
681 char *key = NULL;
682 struct aa_data *data;
683 int i, error = -EPROTO;
684 kernel_cap_t tmpcap;
685 u32 tmp;
686
687 *ns_name = NULL;
688
689 /* check that we have the right struct being passed */
690 if (!unpack_nameX(e, AA_STRUCT, "profile"))
691 goto fail;
692 if (!unpack_str(e, &name, NULL))
693 goto fail;
694 if (*name == '\0')
695 goto fail;
696
697 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
698 if (tmpns) {
699 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
700 if (!*ns_name) {
701 info = "out of memory";
702 goto fail;
703 }
704 name = tmpname;
705 }
706
707 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
708 if (!profile)
709 return ERR_PTR(-ENOMEM);
710
711 /* profile renaming is optional */
712 (void) unpack_str(e, &profile->rename, "rename");
713
714 /* attachment string is optional */
715 (void) unpack_str(e, &profile->attach, "attach");
716
717 /* xmatch is optional and may be NULL */
718 profile->xmatch = unpack_dfa(e);
719 if (IS_ERR(profile->xmatch)) {
720 error = PTR_ERR(profile->xmatch);
721 profile->xmatch = NULL;
722 info = "bad xmatch";
723 goto fail;
724 }
725 /* xmatch_len is not optional if xmatch is set */
726 if (profile->xmatch) {
727 if (!unpack_u32(e, &tmp, NULL)) {
728 info = "missing xmatch len";
729 goto fail;
730 }
731 profile->xmatch_len = tmp;
732 }
733
734 /* disconnected attachment string is optional */
735 (void) unpack_str(e, &profile->disconnected, "disconnected");
736
737 /* per profile debug flags (complain, audit) */
738 if (!unpack_nameX(e, AA_STRUCT, "flags")) {
739 info = "profile missing flags";
740 goto fail;
741 }
742 info = "failed to unpack profile flags";
743 if (!unpack_u32(e, &tmp, NULL))
744 goto fail;
745 if (tmp & PACKED_FLAG_HAT)
746 profile->label.flags |= FLAG_HAT;
747 if (!unpack_u32(e, &tmp, NULL))
748 goto fail;
749 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
750 profile->mode = APPARMOR_COMPLAIN;
751 else if (tmp == PACKED_MODE_ENFORCE)
752 profile->mode = APPARMOR_ENFORCE;
753 else if (tmp == PACKED_MODE_KILL)
754 profile->mode = APPARMOR_KILL;
755 else if (tmp == PACKED_MODE_UNCONFINED)
756 profile->mode = APPARMOR_UNCONFINED;
757 else
758 goto fail;
759 if (!unpack_u32(e, &tmp, NULL))
760 goto fail;
761 if (tmp)
762 profile->audit = AUDIT_ALL;
763
764 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
765 goto fail;
766
767 /* path_flags is optional */
768 if (unpack_u32(e, &profile->path_flags, "path_flags"))
769 profile->path_flags |= profile->label.flags &
770 PATH_MEDIATE_DELETED;
771 else
772 /* set a default value if path_flags field is not present */
773 profile->path_flags = PATH_MEDIATE_DELETED;
774
775 info = "failed to unpack profile capabilities";
776 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
777 goto fail;
778 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
779 goto fail;
780 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
781 goto fail;
782 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
783 goto fail;
784
785 info = "failed to unpack upper profile capabilities";
786 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
787 /* optional upper half of 64 bit caps */
788 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
789 goto fail;
790 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
791 goto fail;
792 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
793 goto fail;
794 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
795 goto fail;
796 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
797 goto fail;
798 }
799
800 info = "failed to unpack extended profile capabilities";
801 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
802 /* optional extended caps mediation mask */
803 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
804 goto fail;
805 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
806 goto fail;
807 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
808 goto fail;
809 }
810
811 if (!unpack_xattrs(e, profile)) {
812 info = "failed to unpack profile xattrs";
813 goto fail;
814 }
815
816 if (!unpack_rlimits(e, profile)) {
817 info = "failed to unpack profile rlimits";
818 goto fail;
819 }
820
821 if (!unpack_secmark(e, profile)) {
822 info = "failed to unpack profile secmark rules";
823 goto fail;
824 }
825
826 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
827 /* generic policy dfa - optional and may be NULL */
828 info = "failed to unpack policydb";
829 profile->policy.dfa = unpack_dfa(e);
830 if (IS_ERR(profile->policy.dfa)) {
831 error = PTR_ERR(profile->policy.dfa);
832 profile->policy.dfa = NULL;
833 goto fail;
834 } else if (!profile->policy.dfa) {
835 error = -EPROTO;
836 goto fail;
837 }
838 if (!unpack_u32(e, &profile->policy.start[0], "start"))
839 /* default start state */
840 profile->policy.start[0] = DFA_START;
841 /* setup class index */
842 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
843 profile->policy.start[i] =
844 aa_dfa_next(profile->policy.dfa,
845 profile->policy.start[0],
846 i);
847 }
848 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
849 goto fail;
850 } else
851 profile->policy.dfa = aa_get_dfa(nulldfa);
852
853 /* get file rules */
854 profile->file.dfa = unpack_dfa(e);
855 if (IS_ERR(profile->file.dfa)) {
856 error = PTR_ERR(profile->file.dfa);
857 profile->file.dfa = NULL;
858 info = "failed to unpack profile file rules";
859 goto fail;
860 } else if (profile->file.dfa) {
861 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
862 /* default start state */
863 profile->file.start = DFA_START;
864 } else if (profile->policy.dfa &&
865 profile->policy.start[AA_CLASS_FILE]) {
866 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
867 profile->file.start = profile->policy.start[AA_CLASS_FILE];
868 } else
869 profile->file.dfa = aa_get_dfa(nulldfa);
870
871 if (!unpack_trans_table(e, profile)) {
872 info = "failed to unpack profile transition table";
873 goto fail;
874 }
875
876 if (unpack_nameX(e, AA_STRUCT, "data")) {
877 info = "out of memory";
878 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
879 if (!profile->data)
880 goto fail;
881
882 params.nelem_hint = 3;
883 params.key_len = sizeof(void *);
884 params.key_offset = offsetof(struct aa_data, key);
885 params.head_offset = offsetof(struct aa_data, head);
886 params.hashfn = strhash;
887 params.obj_cmpfn = datacmp;
888
889 if (rhashtable_init(profile->data, ¶ms)) {
890 info = "failed to init key, value hash table";
891 goto fail;
892 }
893
894 while (unpack_strdup(e, &key, NULL)) {
895 data = kzalloc(sizeof(*data), GFP_KERNEL);
896 if (!data) {
897 kfree_sensitive(key);
898 goto fail;
899 }
900
901 data->key = key;
902 data->size = unpack_blob(e, &data->data, NULL);
903 data->data = kvmemdup(data->data, data->size);
904 if (data->size && !data->data) {
905 kfree_sensitive(data->key);
906 kfree_sensitive(data);
907 goto fail;
908 }
909
910 rhashtable_insert_fast(profile->data, &data->head,
911 profile->data->p);
912 }
913
914 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
915 info = "failed to unpack end of key, value data table";
916 goto fail;
917 }
918 }
919
920 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
921 info = "failed to unpack end of profile";
922 goto fail;
923 }
924
925 return profile;
926
927fail:
928 if (profile)
929 name = NULL;
930 else if (!name)
931 name = "unknown";
932 audit_iface(profile, NULL, name, info, e, error);
933 aa_free_profile(profile);
934
935 return ERR_PTR(error);
936}
937
938/**
939 * verify_head - unpack serialized stream header
940 * @e: serialized data read head (NOT NULL)
941 * @required: whether the header is required or optional
942 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
943 *
944 * Returns: error or 0 if header is good
945 */
946static int verify_header(struct aa_ext *e, int required, const char **ns)
947{
948 int error = -EPROTONOSUPPORT;
949 const char *name = NULL;
950 *ns = NULL;
951
952 /* get the interface version */
953 if (!unpack_u32(e, &e->version, "version")) {
954 if (required) {
955 audit_iface(NULL, NULL, NULL, "invalid profile format",
956 e, error);
957 return error;
958 }
959 }
960
961 /* Check that the interface version is currently supported.
962 * if not specified use previous version
963 * Mask off everything that is not kernel abi version
964 */
965 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
966 audit_iface(NULL, NULL, NULL, "unsupported interface version",
967 e, error);
968 return error;
969 }
970
971 /* read the namespace if present */
972 if (unpack_str(e, &name, "namespace")) {
973 if (*name == '\0') {
974 audit_iface(NULL, NULL, NULL, "invalid namespace name",
975 e, error);
976 return error;
977 }
978 if (*ns && strcmp(*ns, name)) {
979 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
980 error);
981 } else if (!*ns) {
982 *ns = kstrdup(name, GFP_KERNEL);
983 if (!*ns)
984 return -ENOMEM;
985 }
986 }
987
988 return 0;
989}
990
991static bool verify_xindex(int xindex, int table_size)
992{
993 int index, xtype;
994 xtype = xindex & AA_X_TYPE_MASK;
995 index = xindex & AA_X_INDEX_MASK;
996 if (xtype == AA_X_TABLE && index >= table_size)
997 return false;
998 return true;
999}
1000
1001/* verify dfa xindexes are in range of transition tables */
1002static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
1003{
1004 int i;
1005 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
1006 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
1007 return false;
1008 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
1009 return false;
1010 }
1011 return true;
1012}
1013
1014/**
1015 * verify_profile - Do post unpack analysis to verify profile consistency
1016 * @profile: profile to verify (NOT NULL)
1017 *
1018 * Returns: 0 if passes verification else error
1019 */
1020static int verify_profile(struct aa_profile *profile)
1021{
1022 if (profile->file.dfa &&
1023 !verify_dfa_xindex(profile->file.dfa,
1024 profile->file.trans.size)) {
1025 audit_iface(profile, NULL, NULL, "Invalid named transition",
1026 NULL, -EPROTO);
1027 return -EPROTO;
1028 }
1029
1030 return 0;
1031}
1032
1033void aa_load_ent_free(struct aa_load_ent *ent)
1034{
1035 if (ent) {
1036 aa_put_profile(ent->rename);
1037 aa_put_profile(ent->old);
1038 aa_put_profile(ent->new);
1039 kfree(ent->ns_name);
1040 kfree_sensitive(ent);
1041 }
1042}
1043
1044struct aa_load_ent *aa_load_ent_alloc(void)
1045{
1046 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
1047 if (ent)
1048 INIT_LIST_HEAD(&ent->list);
1049 return ent;
1050}
1051
1052static int deflate_compress(const char *src, size_t slen, char **dst,
1053 size_t *dlen)
1054{
1055 int error;
1056 struct z_stream_s strm;
1057 void *stgbuf, *dstbuf;
1058 size_t stglen = deflateBound(slen);
1059
1060 memset(&strm, 0, sizeof(strm));
1061
1062 if (stglen < slen)
1063 return -EFBIG;
1064
1065 strm.workspace = kvzalloc(zlib_deflate_workspacesize(MAX_WBITS,
1066 MAX_MEM_LEVEL),
1067 GFP_KERNEL);
1068 if (!strm.workspace)
1069 return -ENOMEM;
1070
1071 error = zlib_deflateInit(&strm, aa_g_rawdata_compression_level);
1072 if (error != Z_OK) {
1073 error = -ENOMEM;
1074 goto fail_deflate_init;
1075 }
1076
1077 stgbuf = kvzalloc(stglen, GFP_KERNEL);
1078 if (!stgbuf) {
1079 error = -ENOMEM;
1080 goto fail_stg_alloc;
1081 }
1082
1083 strm.next_in = src;
1084 strm.avail_in = slen;
1085 strm.next_out = stgbuf;
1086 strm.avail_out = stglen;
1087
1088 error = zlib_deflate(&strm, Z_FINISH);
1089 if (error != Z_STREAM_END) {
1090 error = -EINVAL;
1091 goto fail_deflate;
1092 }
1093 error = 0;
1094
1095 if (is_vmalloc_addr(stgbuf)) {
1096 dstbuf = kvzalloc(strm.total_out, GFP_KERNEL);
1097 if (dstbuf) {
1098 memcpy(dstbuf, stgbuf, strm.total_out);
1099 kvfree(stgbuf);
1100 }
1101 } else
1102 /*
1103 * If the staging buffer was kmalloc'd, then using krealloc is
1104 * probably going to be faster. The destination buffer will
1105 * always be smaller, so it's just shrunk, avoiding a memcpy
1106 */
1107 dstbuf = krealloc(stgbuf, strm.total_out, GFP_KERNEL);
1108
1109 if (!dstbuf) {
1110 error = -ENOMEM;
1111 goto fail_deflate;
1112 }
1113
1114 *dst = dstbuf;
1115 *dlen = strm.total_out;
1116
1117fail_stg_alloc:
1118 zlib_deflateEnd(&strm);
1119fail_deflate_init:
1120 kvfree(strm.workspace);
1121 return error;
1122
1123fail_deflate:
1124 kvfree(stgbuf);
1125 goto fail_stg_alloc;
1126}
1127
1128static int compress_loaddata(struct aa_loaddata *data)
1129{
1130
1131 AA_BUG(data->compressed_size > 0);
1132
1133 /*
1134 * Shortcut the no compression case, else we increase the amount of
1135 * storage required by a small amount
1136 */
1137 if (aa_g_rawdata_compression_level != 0) {
1138 void *udata = data->data;
1139 int error = deflate_compress(udata, data->size, &data->data,
1140 &data->compressed_size);
1141 if (error)
1142 return error;
1143
1144 kvfree(udata);
1145 } else
1146 data->compressed_size = data->size;
1147
1148 return 0;
1149}
1150
1151/**
1152 * aa_unpack - unpack packed binary profile(s) data loaded from user space
1153 * @udata: user data copied to kmem (NOT NULL)
1154 * @lh: list to place unpacked profiles in a aa_repl_ws
1155 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
1156 *
1157 * Unpack user data and return refcounted allocated profile(s) stored in
1158 * @lh in order of discovery, with the list chain stored in base.list
1159 * or error
1160 *
1161 * Returns: profile(s) on @lh else error pointer if fails to unpack
1162 */
1163int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
1164 const char **ns)
1165{
1166 struct aa_load_ent *tmp, *ent;
1167 struct aa_profile *profile = NULL;
1168 int error;
1169 struct aa_ext e = {
1170 .start = udata->data,
1171 .end = udata->data + udata->size,
1172 .pos = udata->data,
1173 };
1174
1175 *ns = NULL;
1176 while (e.pos < e.end) {
1177 char *ns_name = NULL;
1178 void *start;
1179 error = verify_header(&e, e.pos == e.start, ns);
1180 if (error)
1181 goto fail;
1182
1183 start = e.pos;
1184 profile = unpack_profile(&e, &ns_name);
1185 if (IS_ERR(profile)) {
1186 error = PTR_ERR(profile);
1187 goto fail;
1188 }
1189
1190 error = verify_profile(profile);
1191 if (error)
1192 goto fail_profile;
1193
1194 if (aa_g_hash_policy)
1195 error = aa_calc_profile_hash(profile, e.version, start,
1196 e.pos - start);
1197 if (error)
1198 goto fail_profile;
1199
1200 ent = aa_load_ent_alloc();
1201 if (!ent) {
1202 error = -ENOMEM;
1203 goto fail_profile;
1204 }
1205
1206 ent->new = profile;
1207 ent->ns_name = ns_name;
1208 list_add_tail(&ent->list, lh);
1209 }
1210 udata->abi = e.version & K_ABI_MASK;
1211 if (aa_g_hash_policy) {
1212 udata->hash = aa_calc_hash(udata->data, udata->size);
1213 if (IS_ERR(udata->hash)) {
1214 error = PTR_ERR(udata->hash);
1215 udata->hash = NULL;
1216 goto fail;
1217 }
1218 }
1219 error = compress_loaddata(udata);
1220 if (error)
1221 goto fail;
1222 return 0;
1223
1224fail_profile:
1225 aa_put_profile(profile);
1226
1227fail:
1228 list_for_each_entry_safe(ent, tmp, lh, list) {
1229 list_del_init(&ent->list);
1230 aa_load_ent_free(ent);
1231 }
1232
1233 return error;
1234}
1235
1236#ifdef CONFIG_SECURITY_APPARMOR_KUNIT_TEST
1237#include "policy_unpack_test.c"
1238#endif /* CONFIG_SECURITY_APPARMOR_KUNIT_TEST */