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
41 #define v8 8 /* full network masking */
42
43 /*
44 * The AppArmor interface treats data as a type byte followed by the
45 * actual data. The interface has the notion of a a named entry
46 * which has a name (AA_NAME typecode followed by name string) followed by
47 * the entries typecode and data. Named types allow for optional
48 * elements and extensions to be added and tested for without breaking
49 * backwards compatibility.
50 */
51
52 enum aa_code {
53 AA_U8,
54 AA_U16,
55 AA_U32,
56 AA_U64,
57 AA_NAME, /* same as string except it is items name */
58 AA_STRING,
59 AA_BLOB,
60 AA_STRUCT,
61 AA_STRUCTEND,
62 AA_LIST,
63 AA_LISTEND,
64 AA_ARRAY,
65 AA_ARRAYEND,
66 };
67
68 /*
69 * aa_ext is the read of the buffer containing the serialized profile. The
70 * data is copied into a kernel buffer in apparmorfs and then handed off to
71 * the unpack routines.
72 */
73 struct aa_ext {
74 void *start;
75 void *end;
76 void *pos; /* pointer to current position in the buffer */
77 u32 version;
78 };
79
80 /* audit callback for unpack fields */
audit_cb(struct audit_buffer * ab,void * va)81 static void audit_cb(struct audit_buffer *ab, void *va)
82 {
83 struct common_audit_data *sa = va;
84
85 if (aad(sa)->iface.ns) {
86 audit_log_format(ab, " ns=");
87 audit_log_untrustedstring(ab, aad(sa)->iface.ns);
88 }
89 if (aad(sa)->name) {
90 audit_log_format(ab, " name=");
91 audit_log_untrustedstring(ab, aad(sa)->name);
92 }
93 if (aad(sa)->iface.pos)
94 audit_log_format(ab, " offset=%ld", aad(sa)->iface.pos);
95 }
96
97 /**
98 * audit_iface - do audit message for policy unpacking/load/replace/remove
99 * @new: profile if it has been allocated (MAYBE NULL)
100 * @ns_name: name of the ns the profile is to be loaded to (MAY BE NULL)
101 * @name: name of the profile being manipulated (MAYBE NULL)
102 * @info: any extra info about the failure (MAYBE NULL)
103 * @e: buffer position info
104 * @error: error code
105 *
106 * Returns: %0 or error
107 */
audit_iface(struct aa_profile * new,const char * ns_name,const char * name,const char * info,struct aa_ext * e,int error)108 static int audit_iface(struct aa_profile *new, const char *ns_name,
109 const char *name, const char *info, struct aa_ext *e,
110 int error)
111 {
112 struct aa_profile *profile = labels_profile(aa_current_raw_label());
113 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, NULL);
114 if (e)
115 aad(&sa)->iface.pos = e->pos - e->start;
116 aad(&sa)->iface.ns = ns_name;
117 if (new)
118 aad(&sa)->name = new->base.hname;
119 else
120 aad(&sa)->name = name;
121 aad(&sa)->info = info;
122 aad(&sa)->error = error;
123
124 return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
125 }
126
__aa_loaddata_update(struct aa_loaddata * data,long revision)127 void __aa_loaddata_update(struct aa_loaddata *data, long revision)
128 {
129 AA_BUG(!data);
130 AA_BUG(!data->ns);
131 AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
132 AA_BUG(!mutex_is_locked(&data->ns->lock));
133 AA_BUG(data->revision > revision);
134
135 data->revision = revision;
136 d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
137 current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
138 d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
139 current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
140 }
141
aa_rawdata_eq(struct aa_loaddata * l,struct aa_loaddata * r)142 bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
143 {
144 if (l->size != r->size)
145 return false;
146 if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
147 return false;
148 return memcmp(l->data, r->data, r->size) == 0;
149 }
150
151 /*
152 * need to take the ns mutex lock which is NOT safe most places that
153 * put_loaddata is called, so we have to delay freeing it
154 */
do_loaddata_free(struct work_struct * work)155 static void do_loaddata_free(struct work_struct *work)
156 {
157 struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
158 struct aa_ns *ns = aa_get_ns(d->ns);
159
160 if (ns) {
161 mutex_lock_nested(&ns->lock, ns->level);
162 __aa_fs_remove_rawdata(d);
163 mutex_unlock(&ns->lock);
164 aa_put_ns(ns);
165 }
166
167 kzfree(d->hash);
168 kzfree(d->name);
169 kvfree(d->data);
170 kzfree(d);
171 }
172
aa_loaddata_kref(struct kref * kref)173 void aa_loaddata_kref(struct kref *kref)
174 {
175 struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
176
177 if (d) {
178 INIT_WORK(&d->work, do_loaddata_free);
179 schedule_work(&d->work);
180 }
181 }
182
aa_loaddata_alloc(size_t size)183 struct aa_loaddata *aa_loaddata_alloc(size_t size)
184 {
185 struct aa_loaddata *d;
186
187 d = kzalloc(sizeof(*d), GFP_KERNEL);
188 if (d == NULL)
189 return ERR_PTR(-ENOMEM);
190 d->data = kvzalloc(size, GFP_KERNEL);
191 if (!d->data) {
192 kfree(d);
193 return ERR_PTR(-ENOMEM);
194 }
195 kref_init(&d->count);
196 INIT_LIST_HEAD(&d->list);
197
198 return d;
199 }
200
201 /* test if read will be in packed data bounds */
inbounds(struct aa_ext * e,size_t size)202 static bool inbounds(struct aa_ext *e, size_t size)
203 {
204 return (size <= e->end - e->pos);
205 }
206
kvmemdup(const void * src,size_t len)207 static void *kvmemdup(const void *src, size_t len)
208 {
209 void *p = kvmalloc(len, GFP_KERNEL);
210
211 if (p)
212 memcpy(p, src, len);
213 return p;
214 }
215
216 /**
217 * aa_u16_chunck - test and do bounds checking for a u16 size based chunk
218 * @e: serialized data read head (NOT NULL)
219 * @chunk: start address for chunk of data (NOT NULL)
220 *
221 * Returns: the size of chunk found with the read head at the end of the chunk.
222 */
unpack_u16_chunk(struct aa_ext * e,char ** chunk)223 static size_t unpack_u16_chunk(struct aa_ext *e, char **chunk)
224 {
225 size_t size = 0;
226
227 if (!inbounds(e, sizeof(u16)))
228 return 0;
229 size = le16_to_cpu(get_unaligned((__le16 *) e->pos));
230 e->pos += sizeof(__le16);
231 if (!inbounds(e, size))
232 return 0;
233 *chunk = e->pos;
234 e->pos += size;
235 return size;
236 }
237
238 /* unpack control byte */
unpack_X(struct aa_ext * e,enum aa_code code)239 static bool unpack_X(struct aa_ext *e, enum aa_code code)
240 {
241 if (!inbounds(e, 1))
242 return 0;
243 if (*(u8 *) e->pos != code)
244 return 0;
245 e->pos++;
246 return 1;
247 }
248
249 /**
250 * unpack_nameX - check is the next element is of type X with a name of @name
251 * @e: serialized data extent information (NOT NULL)
252 * @code: type code
253 * @name: name to match to the serialized element. (MAYBE NULL)
254 *
255 * check that the next serialized data element is of type X and has a tag
256 * name @name. If @name is specified then there must be a matching
257 * name element in the stream. If @name is NULL any name element will be
258 * skipped and only the typecode will be tested.
259 *
260 * Returns 1 on success (both type code and name tests match) and the read
261 * head is advanced past the headers
262 *
263 * Returns: 0 if either match fails, the read head does not move
264 */
unpack_nameX(struct aa_ext * e,enum aa_code code,const char * name)265 static bool unpack_nameX(struct aa_ext *e, enum aa_code code, const char *name)
266 {
267 /*
268 * May need to reset pos if name or type doesn't match
269 */
270 void *pos = e->pos;
271 /*
272 * Check for presence of a tagname, and if present name size
273 * AA_NAME tag value is a u16.
274 */
275 if (unpack_X(e, AA_NAME)) {
276 char *tag = NULL;
277 size_t size = unpack_u16_chunk(e, &tag);
278 /* if a name is specified it must match. otherwise skip tag */
279 if (name && (!size || strcmp(name, tag)))
280 goto fail;
281 } else if (name) {
282 /* if a name is specified and there is no name tag fail */
283 goto fail;
284 }
285
286 /* now check if type code matches */
287 if (unpack_X(e, code))
288 return 1;
289
290 fail:
291 e->pos = pos;
292 return 0;
293 }
294
unpack_u32(struct aa_ext * e,u32 * data,const char * name)295 static bool unpack_u32(struct aa_ext *e, u32 *data, const char *name)
296 {
297 if (unpack_nameX(e, AA_U32, name)) {
298 if (!inbounds(e, sizeof(u32)))
299 return 0;
300 if (data)
301 *data = le32_to_cpu(get_unaligned((__le32 *) e->pos));
302 e->pos += sizeof(u32);
303 return 1;
304 }
305 return 0;
306 }
307
unpack_u64(struct aa_ext * e,u64 * data,const char * name)308 static bool unpack_u64(struct aa_ext *e, u64 *data, const char *name)
309 {
310 if (unpack_nameX(e, AA_U64, name)) {
311 if (!inbounds(e, sizeof(u64)))
312 return 0;
313 if (data)
314 *data = le64_to_cpu(get_unaligned((__le64 *) e->pos));
315 e->pos += sizeof(u64);
316 return 1;
317 }
318 return 0;
319 }
320
unpack_array(struct aa_ext * e,const char * name)321 static size_t unpack_array(struct aa_ext *e, const char *name)
322 {
323 if (unpack_nameX(e, AA_ARRAY, name)) {
324 int size;
325 if (!inbounds(e, sizeof(u16)))
326 return 0;
327 size = (int)le16_to_cpu(get_unaligned((__le16 *) e->pos));
328 e->pos += sizeof(u16);
329 return size;
330 }
331 return 0;
332 }
333
unpack_blob(struct aa_ext * e,char ** blob,const char * name)334 static size_t unpack_blob(struct aa_ext *e, char **blob, const char *name)
335 {
336 if (unpack_nameX(e, AA_BLOB, name)) {
337 u32 size;
338 if (!inbounds(e, sizeof(u32)))
339 return 0;
340 size = le32_to_cpu(get_unaligned((__le32 *) e->pos));
341 e->pos += sizeof(u32);
342 if (inbounds(e, (size_t) size)) {
343 *blob = e->pos;
344 e->pos += size;
345 return size;
346 }
347 }
348 return 0;
349 }
350
unpack_str(struct aa_ext * e,const char ** string,const char * name)351 static int unpack_str(struct aa_ext *e, const char **string, const char *name)
352 {
353 char *src_str;
354 size_t size = 0;
355 void *pos = e->pos;
356 *string = NULL;
357 if (unpack_nameX(e, AA_STRING, name)) {
358 size = unpack_u16_chunk(e, &src_str);
359 if (size) {
360 /* strings are null terminated, length is size - 1 */
361 if (src_str[size - 1] != 0)
362 goto fail;
363 *string = src_str;
364 }
365 }
366 return size;
367
368 fail:
369 e->pos = pos;
370 return 0;
371 }
372
unpack_strdup(struct aa_ext * e,char ** string,const char * name)373 static int unpack_strdup(struct aa_ext *e, char **string, const char *name)
374 {
375 const char *tmp;
376 void *pos = e->pos;
377 int res = unpack_str(e, &tmp, name);
378 *string = NULL;
379
380 if (!res)
381 return 0;
382
383 *string = kmemdup(tmp, res, GFP_KERNEL);
384 if (!*string) {
385 e->pos = pos;
386 return 0;
387 }
388
389 return res;
390 }
391
392
393 /**
394 * unpack_dfa - unpack a file rule dfa
395 * @e: serialized data extent information (NOT NULL)
396 *
397 * returns dfa or ERR_PTR or NULL if no dfa
398 */
unpack_dfa(struct aa_ext * e)399 static struct aa_dfa *unpack_dfa(struct aa_ext *e)
400 {
401 char *blob = NULL;
402 size_t size;
403 struct aa_dfa *dfa = NULL;
404
405 size = unpack_blob(e, &blob, "aadfa");
406 if (size) {
407 /*
408 * The dfa is aligned with in the blob to 8 bytes
409 * from the beginning of the stream.
410 * alignment adjust needed by dfa unpack
411 */
412 size_t sz = blob - (char *) e->start -
413 ((e->pos - e->start) & 7);
414 size_t pad = ALIGN(sz, 8) - sz;
415 int flags = TO_ACCEPT1_FLAG(YYTD_DATA32) |
416 TO_ACCEPT2_FLAG(YYTD_DATA32) | DFA_FLAG_VERIFY_STATES;
417 dfa = aa_dfa_unpack(blob + pad, size - pad, flags);
418
419 if (IS_ERR(dfa))
420 return dfa;
421
422 }
423
424 return dfa;
425 }
426
427 /**
428 * unpack_trans_table - unpack a profile transition table
429 * @e: serialized data extent information (NOT NULL)
430 * @profile: profile to add the accept table to (NOT NULL)
431 *
432 * Returns: 1 if table successfully unpacked
433 */
unpack_trans_table(struct aa_ext * e,struct aa_profile * profile)434 static bool unpack_trans_table(struct aa_ext *e, struct aa_profile *profile)
435 {
436 void *saved_pos = e->pos;
437
438 /* exec table is optional */
439 if (unpack_nameX(e, AA_STRUCT, "xtable")) {
440 int i, size;
441
442 size = unpack_array(e, NULL);
443 /* currently 4 exec bits and entries 0-3 are reserved iupcx */
444 if (size > 16 - 4)
445 goto fail;
446 profile->file.trans.table = kcalloc(size, sizeof(char *),
447 GFP_KERNEL);
448 if (!profile->file.trans.table)
449 goto fail;
450
451 profile->file.trans.size = size;
452 for (i = 0; i < size; i++) {
453 char *str;
454 int c, j, pos, size2 = unpack_strdup(e, &str, NULL);
455 /* unpack_strdup verifies that the last character is
456 * null termination byte.
457 */
458 if (!size2)
459 goto fail;
460 profile->file.trans.table[i] = str;
461 /* verify that name doesn't start with space */
462 if (isspace(*str))
463 goto fail;
464
465 /* count internal # of internal \0 */
466 for (c = j = 0; j < size2 - 1; j++) {
467 if (!str[j]) {
468 pos = j;
469 c++;
470 }
471 }
472 if (*str == ':') {
473 /* first character after : must be valid */
474 if (!str[1])
475 goto fail;
476 /* beginning with : requires an embedded \0,
477 * verify that exactly 1 internal \0 exists
478 * trailing \0 already verified by unpack_strdup
479 *
480 * convert \0 back to : for label_parse
481 */
482 if (c == 1)
483 str[pos] = ':';
484 else if (c > 1)
485 goto fail;
486 } else if (c)
487 /* fail - all other cases with embedded \0 */
488 goto fail;
489 }
490 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
491 goto fail;
492 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
493 goto fail;
494 }
495 return 1;
496
497 fail:
498 aa_free_domain_entries(&profile->file.trans);
499 e->pos = saved_pos;
500 return 0;
501 }
502
unpack_xattrs(struct aa_ext * e,struct aa_profile * profile)503 static bool unpack_xattrs(struct aa_ext *e, struct aa_profile *profile)
504 {
505 void *pos = e->pos;
506
507 if (unpack_nameX(e, AA_STRUCT, "xattrs")) {
508 int i, size;
509
510 size = unpack_array(e, NULL);
511 profile->xattr_count = size;
512 profile->xattrs = kcalloc(size, sizeof(char *), GFP_KERNEL);
513 if (!profile->xattrs)
514 goto fail;
515 for (i = 0; i < size; i++) {
516 if (!unpack_strdup(e, &profile->xattrs[i], NULL))
517 goto fail;
518 }
519 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
520 goto fail;
521 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
522 goto fail;
523 }
524
525 return 1;
526
527 fail:
528 e->pos = pos;
529 return 0;
530 }
531
unpack_rlimits(struct aa_ext * e,struct aa_profile * profile)532 static bool unpack_rlimits(struct aa_ext *e, struct aa_profile *profile)
533 {
534 void *pos = e->pos;
535
536 /* rlimits are optional */
537 if (unpack_nameX(e, AA_STRUCT, "rlimits")) {
538 int i, size;
539 u32 tmp = 0;
540 if (!unpack_u32(e, &tmp, NULL))
541 goto fail;
542 profile->rlimits.mask = tmp;
543
544 size = unpack_array(e, NULL);
545 if (size > RLIM_NLIMITS)
546 goto fail;
547 for (i = 0; i < size; i++) {
548 u64 tmp2 = 0;
549 int a = aa_map_resource(i);
550 if (!unpack_u64(e, &tmp2, NULL))
551 goto fail;
552 profile->rlimits.limits[a].rlim_max = tmp2;
553 }
554 if (!unpack_nameX(e, AA_ARRAYEND, NULL))
555 goto fail;
556 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
557 goto fail;
558 }
559 return 1;
560
561 fail:
562 e->pos = pos;
563 return 0;
564 }
565
strhash(const void * data,u32 len,u32 seed)566 static u32 strhash(const void *data, u32 len, u32 seed)
567 {
568 const char * const *key = data;
569
570 return jhash(*key, strlen(*key), seed);
571 }
572
datacmp(struct rhashtable_compare_arg * arg,const void * obj)573 static int datacmp(struct rhashtable_compare_arg *arg, const void *obj)
574 {
575 const struct aa_data *data = obj;
576 const char * const *key = arg->key;
577
578 return strcmp(data->key, *key);
579 }
580
581 /**
582 * unpack_profile - unpack a serialized profile
583 * @e: serialized data extent information (NOT NULL)
584 *
585 * NOTE: unpack profile sets audit struct if there is a failure
586 */
unpack_profile(struct aa_ext * e,char ** ns_name)587 static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name)
588 {
589 struct aa_profile *profile = NULL;
590 const char *tmpname, *tmpns = NULL, *name = NULL;
591 const char *info = "failed to unpack profile";
592 size_t ns_len;
593 struct rhashtable_params params = { 0 };
594 char *key = NULL;
595 struct aa_data *data;
596 int i, error = -EPROTO;
597 kernel_cap_t tmpcap;
598 u32 tmp;
599
600 *ns_name = NULL;
601
602 /* check that we have the right struct being passed */
603 if (!unpack_nameX(e, AA_STRUCT, "profile"))
604 goto fail;
605 if (!unpack_str(e, &name, NULL))
606 goto fail;
607 if (*name == '\0')
608 goto fail;
609
610 tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len);
611 if (tmpns) {
612 *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL);
613 if (!*ns_name) {
614 info = "out of memory";
615 goto fail;
616 }
617 name = tmpname;
618 }
619
620 profile = aa_alloc_profile(name, NULL, GFP_KERNEL);
621 if (!profile)
622 return ERR_PTR(-ENOMEM);
623
624 /* profile renaming is optional */
625 (void) unpack_str(e, &profile->rename, "rename");
626
627 /* attachment string is optional */
628 (void) unpack_str(e, &profile->attach, "attach");
629
630 /* xmatch is optional and may be NULL */
631 profile->xmatch = unpack_dfa(e);
632 if (IS_ERR(profile->xmatch)) {
633 error = PTR_ERR(profile->xmatch);
634 profile->xmatch = NULL;
635 info = "bad xmatch";
636 goto fail;
637 }
638 /* xmatch_len is not optional if xmatch is set */
639 if (profile->xmatch) {
640 if (!unpack_u32(e, &tmp, NULL)) {
641 info = "missing xmatch len";
642 goto fail;
643 }
644 profile->xmatch_len = tmp;
645 }
646
647 /* disconnected attachment string is optional */
648 (void) unpack_str(e, &profile->disconnected, "disconnected");
649
650 /* per profile debug flags (complain, audit) */
651 if (!unpack_nameX(e, AA_STRUCT, "flags")) {
652 info = "profile missing flags";
653 goto fail;
654 }
655 info = "failed to unpack profile flags";
656 if (!unpack_u32(e, &tmp, NULL))
657 goto fail;
658 if (tmp & PACKED_FLAG_HAT)
659 profile->label.flags |= FLAG_HAT;
660 if (!unpack_u32(e, &tmp, NULL))
661 goto fail;
662 if (tmp == PACKED_MODE_COMPLAIN || (e->version & FORCE_COMPLAIN_FLAG))
663 profile->mode = APPARMOR_COMPLAIN;
664 else if (tmp == PACKED_MODE_KILL)
665 profile->mode = APPARMOR_KILL;
666 else if (tmp == PACKED_MODE_UNCONFINED)
667 profile->mode = APPARMOR_UNCONFINED;
668 if (!unpack_u32(e, &tmp, NULL))
669 goto fail;
670 if (tmp)
671 profile->audit = AUDIT_ALL;
672
673 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
674 goto fail;
675
676 /* path_flags is optional */
677 if (unpack_u32(e, &profile->path_flags, "path_flags"))
678 profile->path_flags |= profile->label.flags &
679 PATH_MEDIATE_DELETED;
680 else
681 /* set a default value if path_flags field is not present */
682 profile->path_flags = PATH_MEDIATE_DELETED;
683
684 info = "failed to unpack profile capabilities";
685 if (!unpack_u32(e, &(profile->caps.allow.cap[0]), NULL))
686 goto fail;
687 if (!unpack_u32(e, &(profile->caps.audit.cap[0]), NULL))
688 goto fail;
689 if (!unpack_u32(e, &(profile->caps.quiet.cap[0]), NULL))
690 goto fail;
691 if (!unpack_u32(e, &tmpcap.cap[0], NULL))
692 goto fail;
693
694 info = "failed to unpack upper profile capabilities";
695 if (unpack_nameX(e, AA_STRUCT, "caps64")) {
696 /* optional upper half of 64 bit caps */
697 if (!unpack_u32(e, &(profile->caps.allow.cap[1]), NULL))
698 goto fail;
699 if (!unpack_u32(e, &(profile->caps.audit.cap[1]), NULL))
700 goto fail;
701 if (!unpack_u32(e, &(profile->caps.quiet.cap[1]), NULL))
702 goto fail;
703 if (!unpack_u32(e, &(tmpcap.cap[1]), NULL))
704 goto fail;
705 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
706 goto fail;
707 }
708
709 info = "failed to unpack extended profile capabilities";
710 if (unpack_nameX(e, AA_STRUCT, "capsx")) {
711 /* optional extended caps mediation mask */
712 if (!unpack_u32(e, &(profile->caps.extended.cap[0]), NULL))
713 goto fail;
714 if (!unpack_u32(e, &(profile->caps.extended.cap[1]), NULL))
715 goto fail;
716 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
717 goto fail;
718 }
719
720 if (!unpack_xattrs(e, profile)) {
721 info = "failed to unpack profile xattrs";
722 goto fail;
723 }
724
725 if (!unpack_rlimits(e, profile)) {
726 info = "failed to unpack profile rlimits";
727 goto fail;
728 }
729
730 if (unpack_nameX(e, AA_STRUCT, "policydb")) {
731 /* generic policy dfa - optional and may be NULL */
732 info = "failed to unpack policydb";
733 profile->policy.dfa = unpack_dfa(e);
734 if (IS_ERR(profile->policy.dfa)) {
735 error = PTR_ERR(profile->policy.dfa);
736 profile->policy.dfa = NULL;
737 goto fail;
738 } else if (!profile->policy.dfa) {
739 error = -EPROTO;
740 goto fail;
741 }
742 if (!unpack_u32(e, &profile->policy.start[0], "start"))
743 /* default start state */
744 profile->policy.start[0] = DFA_START;
745 /* setup class index */
746 for (i = AA_CLASS_FILE; i <= AA_CLASS_LAST; i++) {
747 profile->policy.start[i] =
748 aa_dfa_next(profile->policy.dfa,
749 profile->policy.start[0],
750 i);
751 }
752 if (!unpack_nameX(e, AA_STRUCTEND, NULL))
753 goto fail;
754 } else
755 profile->policy.dfa = aa_get_dfa(nulldfa);
756
757 /* get file rules */
758 profile->file.dfa = unpack_dfa(e);
759 if (IS_ERR(profile->file.dfa)) {
760 error = PTR_ERR(profile->file.dfa);
761 profile->file.dfa = NULL;
762 info = "failed to unpack profile file rules";
763 goto fail;
764 } else if (profile->file.dfa) {
765 if (!unpack_u32(e, &profile->file.start, "dfa_start"))
766 /* default start state */
767 profile->file.start = DFA_START;
768 } else if (profile->policy.dfa &&
769 profile->policy.start[AA_CLASS_FILE]) {
770 profile->file.dfa = aa_get_dfa(profile->policy.dfa);
771 profile->file.start = profile->policy.start[AA_CLASS_FILE];
772 } else
773 profile->file.dfa = aa_get_dfa(nulldfa);
774
775 if (!unpack_trans_table(e, profile)) {
776 info = "failed to unpack profile transition table";
777 goto fail;
778 }
779
780 if (unpack_nameX(e, AA_STRUCT, "data")) {
781 info = "out of memory";
782 profile->data = kzalloc(sizeof(*profile->data), GFP_KERNEL);
783 if (!profile->data)
784 goto fail;
785
786 params.nelem_hint = 3;
787 params.key_len = sizeof(void *);
788 params.key_offset = offsetof(struct aa_data, key);
789 params.head_offset = offsetof(struct aa_data, head);
790 params.hashfn = strhash;
791 params.obj_cmpfn = datacmp;
792
793 if (rhashtable_init(profile->data, ¶ms)) {
794 info = "failed to init key, value hash table";
795 goto fail;
796 }
797
798 while (unpack_strdup(e, &key, NULL)) {
799 data = kzalloc(sizeof(*data), GFP_KERNEL);
800 if (!data) {
801 kzfree(key);
802 goto fail;
803 }
804
805 data->key = key;
806 data->size = unpack_blob(e, &data->data, NULL);
807 data->data = kvmemdup(data->data, data->size);
808 if (data->size && !data->data) {
809 kzfree(data->key);
810 kzfree(data);
811 goto fail;
812 }
813
814 rhashtable_insert_fast(profile->data, &data->head,
815 profile->data->p);
816 }
817
818 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
819 info = "failed to unpack end of key, value data table";
820 goto fail;
821 }
822 }
823
824 if (!unpack_nameX(e, AA_STRUCTEND, NULL)) {
825 info = "failed to unpack end of profile";
826 goto fail;
827 }
828
829 return profile;
830
831 fail:
832 if (profile)
833 name = NULL;
834 else if (!name)
835 name = "unknown";
836 audit_iface(profile, NULL, name, info, e, error);
837 aa_free_profile(profile);
838
839 return ERR_PTR(error);
840 }
841
842 /**
843 * verify_head - unpack serialized stream header
844 * @e: serialized data read head (NOT NULL)
845 * @required: whether the header is required or optional
846 * @ns: Returns - namespace if one is specified else NULL (NOT NULL)
847 *
848 * Returns: error or 0 if header is good
849 */
verify_header(struct aa_ext * e,int required,const char ** ns)850 static int verify_header(struct aa_ext *e, int required, const char **ns)
851 {
852 int error = -EPROTONOSUPPORT;
853 const char *name = NULL;
854 *ns = NULL;
855
856 /* get the interface version */
857 if (!unpack_u32(e, &e->version, "version")) {
858 if (required) {
859 audit_iface(NULL, NULL, NULL, "invalid profile format",
860 e, error);
861 return error;
862 }
863 }
864
865 /* Check that the interface version is currently supported.
866 * if not specified use previous version
867 * Mask off everything that is not kernel abi version
868 */
869 if (VERSION_LT(e->version, v5) || VERSION_GT(e->version, v7)) {
870 audit_iface(NULL, NULL, NULL, "unsupported interface version",
871 e, error);
872 return error;
873 }
874
875 /* read the namespace if present */
876 if (unpack_str(e, &name, "namespace")) {
877 if (*name == '\0') {
878 audit_iface(NULL, NULL, NULL, "invalid namespace name",
879 e, error);
880 return error;
881 }
882 if (*ns && strcmp(*ns, name))
883 audit_iface(NULL, NULL, NULL, "invalid ns change", e,
884 error);
885 else if (!*ns)
886 *ns = name;
887 }
888
889 return 0;
890 }
891
verify_xindex(int xindex,int table_size)892 static bool verify_xindex(int xindex, int table_size)
893 {
894 int index, xtype;
895 xtype = xindex & AA_X_TYPE_MASK;
896 index = xindex & AA_X_INDEX_MASK;
897 if (xtype == AA_X_TABLE && index >= table_size)
898 return 0;
899 return 1;
900 }
901
902 /* verify dfa xindexes are in range of transition tables */
verify_dfa_xindex(struct aa_dfa * dfa,int table_size)903 static bool verify_dfa_xindex(struct aa_dfa *dfa, int table_size)
904 {
905 int i;
906 for (i = 0; i < dfa->tables[YYTD_ID_ACCEPT]->td_lolen; i++) {
907 if (!verify_xindex(dfa_user_xindex(dfa, i), table_size))
908 return 0;
909 if (!verify_xindex(dfa_other_xindex(dfa, i), table_size))
910 return 0;
911 }
912 return 1;
913 }
914
915 /**
916 * verify_profile - Do post unpack analysis to verify profile consistency
917 * @profile: profile to verify (NOT NULL)
918 *
919 * Returns: 0 if passes verification else error
920 */
verify_profile(struct aa_profile * profile)921 static int verify_profile(struct aa_profile *profile)
922 {
923 if (profile->file.dfa &&
924 !verify_dfa_xindex(profile->file.dfa,
925 profile->file.trans.size)) {
926 audit_iface(profile, NULL, NULL, "Invalid named transition",
927 NULL, -EPROTO);
928 return -EPROTO;
929 }
930
931 return 0;
932 }
933
aa_load_ent_free(struct aa_load_ent * ent)934 void aa_load_ent_free(struct aa_load_ent *ent)
935 {
936 if (ent) {
937 aa_put_profile(ent->rename);
938 aa_put_profile(ent->old);
939 aa_put_profile(ent->new);
940 kfree(ent->ns_name);
941 kzfree(ent);
942 }
943 }
944
aa_load_ent_alloc(void)945 struct aa_load_ent *aa_load_ent_alloc(void)
946 {
947 struct aa_load_ent *ent = kzalloc(sizeof(*ent), GFP_KERNEL);
948 if (ent)
949 INIT_LIST_HEAD(&ent->list);
950 return ent;
951 }
952
953 /**
954 * aa_unpack - unpack packed binary profile(s) data loaded from user space
955 * @udata: user data copied to kmem (NOT NULL)
956 * @lh: list to place unpacked profiles in a aa_repl_ws
957 * @ns: Returns namespace profile is in if specified else NULL (NOT NULL)
958 *
959 * Unpack user data and return refcounted allocated profile(s) stored in
960 * @lh in order of discovery, with the list chain stored in base.list
961 * or error
962 *
963 * Returns: profile(s) on @lh else error pointer if fails to unpack
964 */
aa_unpack(struct aa_loaddata * udata,struct list_head * lh,const char ** ns)965 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh,
966 const char **ns)
967 {
968 struct aa_load_ent *tmp, *ent;
969 struct aa_profile *profile = NULL;
970 int error;
971 struct aa_ext e = {
972 .start = udata->data,
973 .end = udata->data + udata->size,
974 .pos = udata->data,
975 };
976
977 *ns = NULL;
978 while (e.pos < e.end) {
979 char *ns_name = NULL;
980 void *start;
981 error = verify_header(&e, e.pos == e.start, ns);
982 if (error)
983 goto fail;
984
985 start = e.pos;
986 profile = unpack_profile(&e, &ns_name);
987 if (IS_ERR(profile)) {
988 error = PTR_ERR(profile);
989 goto fail;
990 }
991
992 error = verify_profile(profile);
993 if (error)
994 goto fail_profile;
995
996 if (aa_g_hash_policy)
997 error = aa_calc_profile_hash(profile, e.version, start,
998 e.pos - start);
999 if (error)
1000 goto fail_profile;
1001
1002 ent = aa_load_ent_alloc();
1003 if (!ent) {
1004 error = -ENOMEM;
1005 goto fail_profile;
1006 }
1007
1008 ent->new = profile;
1009 ent->ns_name = ns_name;
1010 list_add_tail(&ent->list, lh);
1011 }
1012 udata->abi = e.version & K_ABI_MASK;
1013 if (aa_g_hash_policy) {
1014 udata->hash = aa_calc_hash(udata->data, udata->size);
1015 if (IS_ERR(udata->hash)) {
1016 error = PTR_ERR(udata->hash);
1017 udata->hash = NULL;
1018 goto fail;
1019 }
1020 }
1021 return 0;
1022
1023 fail_profile:
1024 aa_put_profile(profile);
1025
1026 fail:
1027 list_for_each_entry_safe(ent, tmp, lh, list) {
1028 list_del_init(&ent->list);
1029 aa_load_ent_free(ent);
1030 }
1031
1032 return error;
1033 }
1034