blob: 138120698f839e049a5cf2460572559f3529e337 [file] [log] [blame]
John Johansen736ec7522010-07-29 14:48:02 -07001/*
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 *
Randy Dunlapd410fa42011-05-19 15:59:38 -070015 * AppArmor uses a serialized binary format for loading policy. To find
16 * policy format documentation look in Documentation/security/apparmor.txt
John Johansen736ec7522010-07-29 14:48:02 -070017 * 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"
John Johansenf8eb8a12013-08-14 11:27:36 -070027#include "include/crypto.h"
John Johansen736ec7522010-07-29 14:48:02 -070028#include "include/match.h"
29#include "include/policy.h"
30#include "include/policy_unpack.h"
John Johansen736ec7522010-07-29 14:48:02 -070031
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;
Eric Paris3b3b0e42012-04-03 09:37:02 -070073 if (sa->aad->iface.target) {
74 struct aa_profile *name = sa->aad->iface.target;
John Johansen736ec7522010-07-29 14:48:02 -070075 audit_log_format(ab, " name=");
76 audit_log_untrustedstring(ab, name->base.hname);
77 }
Eric Paris3b3b0e42012-04-03 09:37:02 -070078 if (sa->aad->iface.pos)
79 audit_log_format(ab, " offset=%ld", sa->aad->iface.pos);
John Johansen736ec7522010-07-29 14:48:02 -070080}
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)
John Johansenb1b4bc22012-03-10 11:25:30 -080087 * @e: buffer position info
John Johansen736ec7522010-07-29 14:48:02 -070088 * @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;
Eric Paris3b3b0e42012-04-03 09:37:02 -070097 struct apparmor_audit_data aad = {0,};
Eric Paris50c205f2012-04-04 15:01:43 -040098 sa.type = LSM_AUDIT_DATA_NONE;
Eric Paris3b3b0e42012-04-03 09:37:02 -070099 sa.aad = &aad;
John Johansenb1b4bc22012-03-10 11:25:30 -0800100 if (e)
Eric Paris3b3b0e42012-04-03 09:37:02 -0700101 aad.iface.pos = e->pos - e->start;
102 aad.iface.target = new;
103 aad.name = name;
104 aad.info = info;
105 aad.error = error;
John Johansen736ec7522010-07-29 14:48:02 -0700106
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
John Johansen180a6f52013-02-18 16:09:34 -0800293#define DFA_VALID_PERM_MASK 0xffffffff
294#define DFA_VALID_PERM2_MASK 0xffffffff
295
John Johansen736ec7522010-07-29 14:48:02 -0700296/**
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.
John Johansendd51c8482013-07-10 21:05:43 -0700337 * alignment adjust needed by dfa unpack
John Johansen736ec7522010-07-29 14:48:02 -0700338 */
John Johansendd51c8482013-07-10 21:05:43 -0700339 size_t sz = blob - (char *) e->start -
340 ((e->pos - e->start) & 7);
John Johansen736ec7522010-07-29 14:48:02 -0700341 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 *
Lucas De Marchi25985ed2011-03-30 22:57:33 -0300370 * Returns: 1 if table successfully unpacked
John Johansen736ec7522010-07-29 14:48:02 -0700371 */
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;
James Morris7ee95852011-08-29 11:43:02 +1000392 int c, j, size2 = unpack_strdup(e, &str, NULL);
John Johansen736ec7522010-07-29 14:48:02 -0700393 /* unpack_strdup verifies that the last character is
394 * null termination byte.
395 */
James Morris7ee95852011-08-29 11:43:02 +1000396 if (!size2)
John Johansen736ec7522010-07-29 14:48:02 -0700397 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 */
James Morris7ee95852011-08-29 11:43:02 +1000404 for (c = j = 0; j < size2 - 2; j++) {
John Johansen736ec7522010-07-29 14:48:02 -0700405 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++) {
James Morris7ee95852011-08-29 11:43:02 +1000451 u64 tmp2 = 0;
John Johansen736ec7522010-07-29 14:48:02 -0700452 int a = aa_map_resource(i);
James Morris7ee95852011-08-29 11:43:02 +1000453 if (!unpack_u64(e, &tmp2, NULL))
John Johansen736ec7522010-07-29 14:48:02 -0700454 goto fail;
James Morris7ee95852011-08-29 11:43:02 +1000455 profile->rlimits.limits[a].rlim_max = tmp2;
John Johansen736ec7522010-07-29 14:48:02 -0700456 }
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;
John Johansenad5ff3d2012-02-16 07:07:53 -0800479 int i, error = -EPROTO;
John Johansen736ec7522010-07-29 14:48:02 -0700480 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
John Johansen556d0be2013-07-10 21:17:43 -0700496 /* attachment string is optional */
497 (void) unpack_str(e, &profile->attach, "attach");
498
John Johansen736ec7522010-07-29 14:48:02 -0700499 /* 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;
John Johansen03816502013-07-10 21:12:43 -0700518 if (tmp & PACKED_FLAG_HAT)
John Johansen736ec7522010-07-29 14:48:02 -0700519 profile->flags |= PFLAG_HAT;
520 if (!unpack_u32(e, &tmp, NULL))
521 goto fail;
John Johansen03816502013-07-10 21:12:43 -0700522 if (tmp == PACKED_MODE_COMPLAIN)
John Johansen736ec7522010-07-29 14:48:02 -0700523 profile->mode = APPARMOR_COMPLAIN;
John Johansen03816502013-07-10 21:12:43 -0700524 else if (tmp == PACKED_MODE_KILL)
525 profile->mode = APPARMOR_KILL;
526 else if (tmp == PACKED_MODE_UNCONFINED)
527 profile->mode = APPARMOR_UNCONFINED;
John Johansen736ec7522010-07-29 14:48:02 -0700528 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;
John Johansencdbd2882012-02-16 07:06:41 -0800572 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
573 goto fail;
John Johansen736ec7522010-07-29 14:48:02 -0700574 }
575
576 if (!unpack_rlimits(e, profile))
577 goto fail;
578
John Johansenad5ff3d2012-02-16 07:07:53 -0800579 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;
John Johansen5f20fdf2016-06-15 10:00:55 +0300586 } else if (!profile->policy.dfa) {
587 error = -EPROTO;
588 goto fail;
John Johansenad5ff3d2012-02-16 07:07:53 -0800589 }
590 if (!unpack_u32(e, &profile->policy.start[0], "start"))
591 /* default start state */
592 profile->policy.start[0] = DFA_START;
593 /* setup class index */
594 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
595 profile->policy.start[i] =
596 aa_dfa_next(profile->policy.dfa,
597 profile->policy.start[0],
598 i);
599 }
600 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
601 goto fail;
602 }
603
John Johansen736ec7522010-07-29 14:48:02 -0700604 /* get file rules */
605 profile->file.dfa = unpack_dfa(e);
606 if (IS_ERR(profile->file.dfa)) {
607 error = PTR_ERR(profile->file.dfa);
608 profile->file.dfa = NULL;
609 goto fail;
610 }
611
612 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
613 /* default start state */
614 profile->file.start = DFA_START;
615
616 if (!unpack_trans_table(e, profile))
617 goto fail;
618
619 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
620 goto fail;
621
622 return profile;
623
624fail:
625 if (profile)
626 name = NULL;
627 else if (!name)
628 name = "unknown";
629 audit_iface(profile, name, "failed to unpack profile", e, error);
John Johansen8651e1d62013-07-10 21:11:43 -0700630 aa_free_profile(profile);
John Johansen736ec7522010-07-29 14:48:02 -0700631
632 return ERR_PTR(error);
633}
634
635/**
636 * verify_head - unpack serialized stream header
637 * @e: serialized data read head (NOT NULL)
John Johansendd51c8482013-07-10 21:05:43 -0700638 * @required: whether the header is required or optional
John Johansen736ec7522010-07-29 14:48:02 -0700639 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
640 *
641 * Returns: error or 0 if header is good
642 */
John Johansendd51c8482013-07-10 21:05:43 -0700643static int verify_header(struct aa_ext *e, int required, const char **ns)
John Johansen736ec7522010-07-29 14:48:02 -0700644{
645 int error = -EPROTONOSUPPORT;
John Johansendd51c8482013-07-10 21:05:43 -0700646 const char *name = NULL;
647 *ns = NULL;
648
John Johansen736ec7522010-07-29 14:48:02 -0700649 /* get the interface version */
650 if (!unpack_u32(e, &e->version, "version")) {
John Johansendd51c8482013-07-10 21:05:43 -0700651 if (required) {
652 audit_iface(NULL, NULL, "invalid profile format", e,
653 error);
654 return error;
655 }
656
657 /* check that the interface version is currently supported */
658 if (e->version != 5) {
659 audit_iface(NULL, NULL, "unsupported interface version",
660 e, error);
661 return error;
662 }
John Johansen736ec7522010-07-29 14:48:02 -0700663 }
664
John Johansen736ec7522010-07-29 14:48:02 -0700665
666 /* read the namespace if present */
John Johansendd51c8482013-07-10 21:05:43 -0700667 if (unpack_str(e, &name, "namespace")) {
668 if (*ns && strcmp(*ns, name))
669 audit_iface(NULL, NULL, "invalid ns change", e, error);
670 else if (!*ns)
671 *ns = name;
672 }
John Johansen736ec7522010-07-29 14:48:02 -0700673
674 return 0;
675}
676
677static bool verify_xindex(int xindex, int table_size)
678{
679 int index, xtype;
680 xtype = xindex & AA_X_TYPE_MASK;
681 index = xindex & AA_X_INDEX_MASK;
John Johansen23ca7b62016-03-17 12:02:54 -0700682 if (xtype == AA_X_TABLE && index >= table_size)
John Johansen736ec7522010-07-29 14:48:02 -0700683 return 0;
684 return 1;
685}
686
687/* verify dfa xindexes are in range of transition tables */
688static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
689{
690 int i;
691 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
692 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
693 return 0;
694 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
695 return 0;
696 }
697 return 1;
698}
699
700/**
701 * verify_profile - Do post unpack analysis to verify profile consistency
702 * @profile: profile to verify (NOT NULL)
703 *
704 * Returns: 0 if passes verification else error
705 */
706static int verify_profile(struct aa_profile *profile)
707{
708 if (aa_g_paranoid_load) {
709 if (profile->file.dfa &&
710 !verify_dfa_xindex(profile->file.dfa,
711 profile->file.trans.size)) {
712 audit_iface(profile, NULL, "Invalid named transition",
713 NULL, -EPROTO);
714 return -EPROTO;
715 }
716 }
717
718 return 0;
719}
720
John Johansendd51c8482013-07-10 21:05:43 -0700721void aa_load_ent_free(struct aa_load_ent *ent)
722{
723 if (ent) {
724 aa_put_profile(ent->rename);
725 aa_put_profile(ent->old);
726 aa_put_profile(ent->new);
727 kzfree(ent);
728 }
729}
730
731struct aa_load_ent *aa_load_ent_alloc(void)
732{
733 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
734 if (ent)
735 INIT_LIST_HEAD(&ent->list);
736 return ent;
737}
738
John Johansen736ec7522010-07-29 14:48:02 -0700739/**
John Johansendd51c8482013-07-10 21:05:43 -0700740 * aa_unpack - unpack packed binary profile(s) data loaded from user space
John Johansen736ec7522010-07-29 14:48:02 -0700741 * @udata: user data copied to kmem (NOT NULL)
742 * @size: the size of the user data
John Johansendd51c8482013-07-10 21:05:43 -0700743 * @lh: list to place unpacked profiles in a aa_repl_ws
John Johansen736ec7522010-07-29 14:48:02 -0700744 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
745 *
John Johansendd51c8482013-07-10 21:05:43 -0700746 * Unpack user data and return refcounted allocated profile(s) stored in
747 * @lh in order of discovery, with the list chain stored in base.list
748 * or error
John Johansen736ec7522010-07-29 14:48:02 -0700749 *
John Johansendd51c8482013-07-10 21:05:43 -0700750 * Returns: profile(s) on @lh else error pointer if fails to unpack
John Johansen736ec7522010-07-29 14:48:02 -0700751 */
John Johansendd51c8482013-07-10 21:05:43 -0700752int aa_unpack(void *udata, size_t size, struct list_head *lh, const char **ns)
John Johansen736ec7522010-07-29 14:48:02 -0700753{
John Johansendd51c8482013-07-10 21:05:43 -0700754 struct aa_load_ent *tmp, *ent;
John Johansen736ec7522010-07-29 14:48:02 -0700755 struct aa_profile *profile = NULL;
756 int error;
757 struct aa_ext e = {
758 .start = udata,
759 .end = udata + size,
760 .pos = udata,
761 };
762
John Johansendd51c8482013-07-10 21:05:43 -0700763 *ns = NULL;
764 while (e.pos < e.end) {
John Johansenf8eb8a12013-08-14 11:27:36 -0700765 void *start;
John Johansendd51c8482013-07-10 21:05:43 -0700766 error = verify_header(&e, e.pos == e.start, ns);
767 if (error)
768 goto fail;
John Johansen736ec7522010-07-29 14:48:02 -0700769
John Johansenf8eb8a12013-08-14 11:27:36 -0700770 start = e.pos;
John Johansendd51c8482013-07-10 21:05:43 -0700771 profile = unpack_profile(&e);
772 if (IS_ERR(profile)) {
773 error = PTR_ERR(profile);
774 goto fail;
775 }
John Johansen736ec7522010-07-29 14:48:02 -0700776
John Johansendd51c8482013-07-10 21:05:43 -0700777 error = verify_profile(profile);
John Johansenf8eb8a12013-08-14 11:27:36 -0700778 if (error)
779 goto fail_profile;
780
Arnd Bergmann7616ac72016-07-25 10:59:07 -0700781 error = aa_calc_profile_hash(profile, e.version, start,
John Johansen6059f712014-10-24 09:16:14 -0700782 e.pos - start);
John Johansenf8eb8a12013-08-14 11:27:36 -0700783 if (error)
784 goto fail_profile;
John Johansendd51c8482013-07-10 21:05:43 -0700785
786 ent = aa_load_ent_alloc();
787 if (!ent) {
788 error = -ENOMEM;
John Johansenf8eb8a12013-08-14 11:27:36 -0700789 goto fail_profile;
John Johansendd51c8482013-07-10 21:05:43 -0700790 }
791
792 ent->new = profile;
793 list_add_tail(&ent->list, lh);
John Johansen736ec7522010-07-29 14:48:02 -0700794 }
795
John Johansendd51c8482013-07-10 21:05:43 -0700796 return 0;
797
John Johansenf8eb8a12013-08-14 11:27:36 -0700798fail_profile:
799 aa_put_profile(profile);
800
John Johansendd51c8482013-07-10 21:05:43 -0700801fail:
802 list_for_each_entry_safe(ent, tmp, lh, list) {
803 list_del_init(&ent->list);
804 aa_load_ent_free(ent);
805 }
806
807 return error;
John Johansen736ec7522010-07-29 14:48:02 -0700808}