path: root/libavb/avb_slot_verify.c (plain)
blob: 469a788545e0b08dcc25bc49ebfbc476c64a39c8

1	/*
2	* Copyright (C) 2016 The Android Open Source Project
3	*
4	* Permission is hereby granted, free of charge, to any person
5	* obtaining a copy of this software and associated documentation
6	* files (the "Software"), to deal in the Software without
7	* restriction, including without limitation the rights to use, copy,
8	* modify, merge, publish, distribute, sublicense, and/or sell copies
9	* of the Software, and to permit persons to whom the Software is
10	* furnished to do so, subject to the following conditions:
11	*
12	* The above copyright notice and this permission notice shall be
13	* included in all copies or substantial portions of the Software.
14	*
15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
16	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
17	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
18	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
19	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
20	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
21	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
22	* SOFTWARE.
23	*/
24
25	#include "avb_slot_verify.h"
26	#include "avb_chain_partition_descriptor.h"
27	#include "avb_footer.h"
28	#include "avb_hash_descriptor.h"
29	#include "avb_kernel_cmdline_descriptor.h"
30	#include "avb_sha.h"
31	#include "avb_util.h"
32	#include "avb_vbmeta_image.h"
33	#include "avb_version.h"
34
35	/* Maximum allow length (in bytes) of a partition name, including
36	* ab_suffix.
37	*/
38	#define PART_NAME_MAX_SIZE 32
39
40	/* Maximum number of partitions that can be loaded with avb_slot_verify(). */
41	#define MAX_NUMBER_OF_LOADED_PARTITIONS 32
42
43	/* Maximum number of vbmeta images that can be loaded with avb_slot_verify(). */
44	#define MAX_NUMBER_OF_VBMETA_IMAGES 32
45
46	/* Maximum size of a vbmeta image - 64 KiB. */
47	#define VBMETA_MAX_SIZE (64 * 1024)
48
49	/* Helper function to see if we should continue with verification in
50	* allow_verification_error=true mode if something goes wrong. See the
51	* comments for the avb_slot_verify() function for more information.
52	*/
53	static inline bool result_should_continue(AvbSlotVerifyResult result) {
54	switch (result) {
55	case AVB_SLOT_VERIFY_RESULT_ERROR_OOM:
56	case AVB_SLOT_VERIFY_RESULT_ERROR_IO:
57	case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA:
58	case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION:
59	return false;
60
61	case AVB_SLOT_VERIFY_RESULT_OK:
62	case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION:
63	case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX:
64	case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED:
65	return true;
66	}
67
68	return false;
69	}
70
71	static AvbSlotVerifyResult load_and_verify_hash_partition(
72	AvbOps* ops,
73	const char* const* requested_partitions,
74	const char* ab_suffix,
75	bool allow_verification_error,
76	const AvbDescriptor* descriptor,
77	AvbSlotVerifyData* slot_data) {
78	AvbHashDescriptor hash_desc;
79	const uint8_t* desc_partition_name = NULL;
80	const uint8_t* desc_salt;
81	const uint8_t* desc_digest;
82	char part_name[PART_NAME_MAX_SIZE];
83	AvbSlotVerifyResult ret;
84	AvbIOResult io_ret;
85	uint8_t* image_buf = NULL;
86	size_t part_num_read;
87	uint8_t* digest;
88	size_t digest_len;
89	const char* found;
90
91	if (!avb_hash_descriptor_validate_and_byteswap(
92	(const AvbHashDescriptor*)descriptor, &hash_desc)) {
93	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
94	goto out;
95	}
96
97	desc_partition_name =
98	((const uint8_t*)descriptor) + sizeof(AvbHashDescriptor);
99	desc_salt = desc_partition_name + hash_desc.partition_name_len;
100	desc_digest = desc_salt + hash_desc.salt_len;
101
102	if (!avb_validate_utf8(desc_partition_name, hash_desc.partition_name_len)) {
103	avb_error("Partition name is not valid UTF-8.\n");
104	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
105	goto out;
106	}
107
108	if (!avb_str_concat(part_name,
109	sizeof part_name,
110	(const char*)desc_partition_name,
111	hash_desc.partition_name_len,
112	ab_suffix,
113	avb_strlen(ab_suffix))) {
114	avb_error("Partition name and suffix does not fit.\n");
115	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
116	goto out;
117	}
118
119	image_buf = avb_malloc(hash_desc.image_size);
120	if (image_buf == NULL) {
121	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
122	goto out;
123	}
124
125	io_ret = ops->read_from_partition(ops,
126	part_name,
127	0 /* offset */,
128	hash_desc.image_size,
129	image_buf,
130	&part_num_read);
131	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
132	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
133	goto out;
134	} else if (io_ret != AVB_IO_RESULT_OK) {
135	avb_errorv(part_name, ": Error loading data from partition.\n", NULL);
136	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
137	goto out;
138	}
139	if (part_num_read != hash_desc.image_size) {
140	avb_errorv(part_name, ": Read fewer than requested bytes.\n", NULL);
141	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
142	goto out;
143	}
144
145	if (avb_strcmp((const char*)hash_desc.hash_algorithm, "sha256") == 0) {
146	AvbSHA256Ctx sha256_ctx;
147	avb_sha256_init(&sha256_ctx);
148	avb_sha256_update(&sha256_ctx, desc_salt, hash_desc.salt_len);
149	avb_sha256_update(&sha256_ctx, image_buf, hash_desc.image_size);
150	digest = avb_sha256_final(&sha256_ctx);
151	digest_len = AVB_SHA256_DIGEST_SIZE;
152	} else if (avb_strcmp((const char*)hash_desc.hash_algorithm, "sha512") == 0) {
153	AvbSHA512Ctx sha512_ctx;
154	avb_sha512_init(&sha512_ctx);
155	avb_sha512_update(&sha512_ctx, desc_salt, hash_desc.salt_len);
156	avb_sha512_update(&sha512_ctx, image_buf, hash_desc.image_size);
157	digest = avb_sha512_final(&sha512_ctx);
158	digest_len = AVB_SHA512_DIGEST_SIZE;
159	} else {
160	avb_errorv(part_name, ": Unsupported hash algorithm.\n", NULL);
161	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
162	goto out;
163	}
164
165	if (digest_len != hash_desc.digest_len) {
166	avb_errorv(
167	part_name, ": Digest in descriptor not of expected size.\n", NULL);
168	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
169	goto out;
170	}
171
172	if (avb_safe_memcmp(digest, desc_digest, digest_len) != 0) {
173	avb_errorv(part_name,
174	": Hash of data does not match digest in descriptor.\n",
175	NULL);
176	ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
177	goto out;
178	}
179
180	ret = AVB_SLOT_VERIFY_RESULT_OK;
181
182	out:
183
184	if (ret == AVB_SLOT_VERIFY_RESULT_OK || result_should_continue(ret)) {
185	/* If this is the requested partition, copy to slot_data. */
186	found = avb_strv_find_str(requested_partitions,
187	(const char*)desc_partition_name,
188	hash_desc.partition_name_len);
189	if (found != NULL) {
190	AvbPartitionData* loaded_partition;
191	if (slot_data->num_loaded_partitions == MAX_NUMBER_OF_LOADED_PARTITIONS) {
192	avb_errorv(part_name, ": Too many loaded partitions.\n", NULL);
193	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
194	goto fail;
195	}
196	loaded_partition =
197	&slot_data->loaded_partitions[slot_data->num_loaded_partitions++];
198	loaded_partition->partition_name = avb_strdup(found);
199	loaded_partition->data_size = hash_desc.image_size;
200	loaded_partition->data = image_buf;
201	image_buf = NULL;
202	}
203	}
204
205	fail:
206	if (image_buf != NULL) {
207	avb_free(image_buf);
208	}
209	return ret;
210	}
211
212	static AvbSlotVerifyResult load_and_verify_vbmeta(
213	AvbOps* ops,
214	const char* const* requested_partitions,
215	const char* ab_suffix,
216	bool allow_verification_error,
217	AvbVBMetaImageFlags toplevel_vbmeta_flags,
218	int rollback_index_location,
219	const char* partition_name,
220	size_t partition_name_len,
221	const uint8_t* expected_public_key,
222	size_t expected_public_key_length,
223	AvbSlotVerifyData* slot_data,
224	AvbAlgorithmType* out_algorithm_type) {
225	char full_partition_name[PART_NAME_MAX_SIZE];
226	AvbSlotVerifyResult ret;
227	AvbIOResult io_ret;
228	size_t vbmeta_offset;
229	size_t vbmeta_size;
230	uint8_t* vbmeta_buf = NULL;
231	size_t vbmeta_num_read;
232	AvbVBMetaVerifyResult vbmeta_ret;
233	const uint8_t* pk_data;
234	size_t pk_len;
235	AvbVBMetaImageHeader vbmeta_header;
236	uint64_t stored_rollback_index;
237	const AvbDescriptor** descriptors = NULL;
238	size_t num_descriptors;
239	size_t n;
240	bool is_main_vbmeta;
241	bool is_vbmeta_partition;
242	AvbVBMetaData* vbmeta_image_data = NULL;
243
244	ret = AVB_SLOT_VERIFY_RESULT_OK;
245
246	avb_assert(slot_data != NULL);
247
248	/* Since we allow top-level vbmeta in 'boot', use
249	* rollback_index_location to determine whether we're the main
250	* vbmeta struct.
251	*/
252	is_main_vbmeta = (rollback_index_location == 0);
253	is_vbmeta_partition = (avb_strcmp(partition_name, "vbmeta") == 0);
254
255	if (!avb_validate_utf8((const uint8_t*)partition_name, partition_name_len)) {
256	avb_error("Partition name is not valid UTF-8.\n");
257	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
258	goto out;
259	}
260
261	/* Construct full partition name. */
262	if (!avb_str_concat(full_partition_name,
263	sizeof full_partition_name,
264	partition_name,
265	partition_name_len,
266	ab_suffix,
267	avb_strlen(ab_suffix))) {
268	avb_error("Partition name and suffix does not fit.\n");
269	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
270	goto out;
271	}
272
273	avb_debugv("Loading vbmeta struct from partition '",
274	full_partition_name,
275	"'.\n",
276	NULL);
277
278	/* If we're loading from the main vbmeta partition, the vbmeta
279	* struct is in the beginning. Otherwise we have to locate it via a
280	* footer.
281	*/
282	if (is_vbmeta_partition) {
283	vbmeta_offset = 0;
284	vbmeta_size = VBMETA_MAX_SIZE;
285	} else {
286	uint8_t footer_buf[AVB_FOOTER_SIZE];
287	size_t footer_num_read;
288	AvbFooter footer;
289
290	io_ret = ops->read_from_partition(ops,
291	full_partition_name,
292	-AVB_FOOTER_SIZE,
293	AVB_FOOTER_SIZE,
294	footer_buf,
295	&footer_num_read);
296	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
297	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
298	goto out;
299	} else if (io_ret != AVB_IO_RESULT_OK) {
300	avb_errorv(full_partition_name, ": Error loading footer.\n", NULL);
301	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
302	goto out;
303	}
304	avb_assert(footer_num_read == AVB_FOOTER_SIZE);
305
306	if (!avb_footer_validate_and_byteswap((const AvbFooter*)footer_buf,
307	&footer)) {
308	avb_errorv(full_partition_name, ": Error validating footer.\n", NULL);
309	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
310	goto out;
311	}
312
313	/* Basic footer sanity check since the data is untrusted. */
314	if (footer.vbmeta_size > VBMETA_MAX_SIZE) {
315	avb_errorv(
316	full_partition_name, ": Invalid vbmeta size in footer.\n", NULL);
317	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
318	goto out;
319	}
320
321	vbmeta_offset = footer.vbmeta_offset;
322	vbmeta_size = footer.vbmeta_size;
323	}
324
325	vbmeta_buf = avb_malloc(vbmeta_size);
326	if (vbmeta_buf == NULL) {
327	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
328	goto out;
329	}
330
331	io_ret = ops->read_from_partition(ops,
332	full_partition_name,
333	vbmeta_offset,
334	vbmeta_size,
335	vbmeta_buf,
336	&vbmeta_num_read);
337	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
338	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
339	goto out;
340	} else if (io_ret != AVB_IO_RESULT_OK) {
341	/* If we're looking for 'vbmeta' but there is no such partition,
342	* go try to get it from the boot partition instead.
343	*/
344	if (is_main_vbmeta && io_ret == AVB_IO_RESULT_ERROR_NO_SUCH_PARTITION &&
345	is_vbmeta_partition) {
346	avb_debugv(full_partition_name,
347	": No such partition. Trying 'boot' instead.\n",
348	NULL);
349	ret = load_and_verify_vbmeta(ops,
350	requested_partitions,
351	ab_suffix,
352	allow_verification_error,
353	0 /* toplevel_vbmeta_flags */,
354	0 /* rollback_index_location */,
355	"boot",
356	avb_strlen("boot"),
357	NULL /* expected_public_key */,
358	0 /* expected_public_key_length */,
359	slot_data,
360	out_algorithm_type);
361	goto out;
362	} else {
363	avb_errorv(full_partition_name, ": Error loading vbmeta data.\n", NULL);
364	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
365	goto out;
366	}
367	}
368	avb_assert(vbmeta_num_read <= vbmeta_size);
369
370	/* Check if the image is properly signed and get the public key used
371	* to sign the image.
372	*/
373	vbmeta_ret =
374	avb_vbmeta_image_verify(vbmeta_buf, vbmeta_num_read, &pk_data, &pk_len);
375	switch (vbmeta_ret) {
376	case AVB_VBMETA_VERIFY_RESULT_OK:
377	avb_assert(pk_data != NULL && pk_len > 0);
378	break;
379
380	case AVB_VBMETA_VERIFY_RESULT_OK_NOT_SIGNED:
381	case AVB_VBMETA_VERIFY_RESULT_HASH_MISMATCH:
382	case AVB_VBMETA_VERIFY_RESULT_SIGNATURE_MISMATCH:
383	ret = AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION;
384	avb_errorv(full_partition_name,
385	": Error verifying vbmeta image: ",
386	avb_vbmeta_verify_result_to_string(vbmeta_ret),
387	"\n",
388	NULL);
389	if (!allow_verification_error) {
390	goto out;
391	}
392	break;
393
394	case AVB_VBMETA_VERIFY_RESULT_INVALID_VBMETA_HEADER:
395	/* No way to continue this case. */
396	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
397	avb_errorv(full_partition_name,
398	": Error verifying vbmeta image: invalid vbmeta header\n",
399	NULL);
400	goto out;
401
402	case AVB_VBMETA_VERIFY_RESULT_UNSUPPORTED_VERSION:
403	/* No way to continue this case. */
404	ret = AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION;
405	avb_errorv(full_partition_name,
406	": Error verifying vbmeta image: unsupported AVB version\n",
407	NULL);
408	goto out;
409	}
410
411	/* Byteswap the header. */
412	avb_vbmeta_image_header_to_host_byte_order((AvbVBMetaImageHeader*)vbmeta_buf,
413	&vbmeta_header);
414
415	/* If we're the toplevel, assign flags so they'll be passed down. */
416	if (is_main_vbmeta) {
417	toplevel_vbmeta_flags = (AvbVBMetaImageFlags)vbmeta_header.flags;
418	} else {
419	if (vbmeta_header.flags != 0) {
420	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
421	avb_errorv(full_partition_name,
422	": chained vbmeta image has non-zero flags\n",
423	NULL);
424	goto out;
425	}
426	}
427
428	/* Check if key used to make signature matches what is expected. */
429	if (pk_data != NULL) {
430	if (expected_public_key != NULL) {
431	avb_assert(!is_main_vbmeta);
432	if (expected_public_key_length != pk_len ||
433	avb_safe_memcmp(expected_public_key, pk_data, pk_len) != 0) {
434	avb_errorv(full_partition_name,
435	": Public key used to sign data does not match key in chain "
436	"partition descriptor.\n",
437	NULL);
438	ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED;
439	if (!allow_verification_error) {
440	goto out;
441	}
442	}
443	} else {
444	bool key_is_trusted = false;
445	const uint8_t* pk_metadata = NULL;
446	size_t pk_metadata_len = 0;
447
448	if (vbmeta_header.public_key_metadata_size > 0) {
449	pk_metadata = vbmeta_buf + sizeof(AvbVBMetaImageHeader) +
450	vbmeta_header.authentication_data_block_size +
451	vbmeta_header.public_key_metadata_offset;
452	pk_metadata_len = vbmeta_header.public_key_metadata_size;
453	}
454
455	avb_assert(is_main_vbmeta);
456	io_ret = ops->validate_vbmeta_public_key(
457	ops, pk_data, pk_len, pk_metadata, pk_metadata_len, &key_is_trusted);
458	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
459	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
460	goto out;
461	} else if (io_ret != AVB_IO_RESULT_OK) {
462	avb_errorv(full_partition_name,
463	": Error while checking public key used to sign data.\n",
464	NULL);
465	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
466	goto out;
467	}
468	if (!key_is_trusted) {
469	avb_errorv(full_partition_name,
470	": Public key used to sign data rejected.\n",
471	NULL);
472	ret = AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED;
473	if (!allow_verification_error) {
474	goto out;
475	}
476	}
477	}
478	}
479
480	/* Check rollback index. */
481	io_ret = ops->read_rollback_index(
482	ops, rollback_index_location, &stored_rollback_index);
483	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
484	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
485	goto out;
486	} else if (io_ret != AVB_IO_RESULT_OK) {
487	avb_errorv(full_partition_name,
488	": Error getting rollback index for location.\n",
489	NULL);
490	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
491	goto out;
492	}
493	if (vbmeta_header.rollback_index < stored_rollback_index) {
494	avb_errorv(
495	full_partition_name,
496	": Image rollback index is less than the stored rollback index.\n",
497	NULL);
498	ret = AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX;
499	if (!allow_verification_error) {
500	goto out;
501	}
502	}
503
504	/* Copy vbmeta to vbmeta_images before recursing. */
505	if (is_main_vbmeta) {
506	avb_assert(slot_data->num_vbmeta_images == 0);
507	} else {
508	avb_assert(slot_data->num_vbmeta_images > 0);
509	}
510	if (slot_data->num_vbmeta_images == MAX_NUMBER_OF_VBMETA_IMAGES) {
511	avb_errorv(full_partition_name, ": Too many vbmeta images.\n", NULL);
512	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
513	goto out;
514	}
515	vbmeta_image_data = &slot_data->vbmeta_images[slot_data->num_vbmeta_images++];
516	vbmeta_image_data->partition_name = avb_strdup(partition_name);
517	vbmeta_image_data->vbmeta_data = vbmeta_buf;
518	/* Note that |vbmeta_buf| is actually |vbmeta_num_read| bytes long
519	* and this includes data past the end of the image. Pass the
520	* actual size of the vbmeta image. Also, no need to use
521	* avb_safe_add() since the header has already been verified.
522	*/
523	vbmeta_image_data->vbmeta_size =
524	sizeof(AvbVBMetaImageHeader) +
525	vbmeta_header.authentication_data_block_size +
526	vbmeta_header.auxiliary_data_block_size;
527	vbmeta_image_data->verify_result = vbmeta_ret;
528
529	/* Now go through all descriptors and take the appropriate action:
530	*
531	* - hash descriptor: Load data from partition, calculate hash, and
532	* checks that it matches what's in the hash descriptor.
533	*
534	* - hashtree descriptor: Do nothing since verification happens
535	* on-the-fly from within the OS.
536	*
537	* - chained partition descriptor: Load the footer, load the vbmeta
538	* image, verify vbmeta image (includes rollback checks, hash
539	* checks, bail on chained partitions).
540	*/
541	descriptors =
542	avb_descriptor_get_all(vbmeta_buf, vbmeta_num_read, &num_descriptors);
543	for (n = 0; n < num_descriptors; n++) {
544	AvbDescriptor desc;
545
546	if (!avb_descriptor_validate_and_byteswap(descriptors[n], &desc)) {
547	avb_errorv(full_partition_name, ": Descriptor is invalid.\n", NULL);
548	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
549	goto out;
550	}
551
552	switch (desc.tag) {
553	case AVB_DESCRIPTOR_TAG_HASH: {
554	AvbSlotVerifyResult sub_ret;
555	sub_ret = load_and_verify_hash_partition(ops,
556	requested_partitions,
557	ab_suffix,
558	allow_verification_error,
559	descriptors[n],
560	slot_data);
561	if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) {
562	ret = sub_ret;
563	if (!allow_verification_error || !result_should_continue(ret)) {
564	goto out;
565	}
566	}
567	} break;
568
569	case AVB_DESCRIPTOR_TAG_CHAIN_PARTITION: {
570	AvbSlotVerifyResult sub_ret;
571	AvbChainPartitionDescriptor chain_desc;
572	const uint8_t* chain_partition_name;
573	const uint8_t* chain_public_key;
574
575	/* Only allow CHAIN_PARTITION descriptors in the main vbmeta image. */
576	if (!is_main_vbmeta) {
577	avb_errorv(full_partition_name,
578	": Encountered chain descriptor not in main image.\n",
579	NULL);
580	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
581	goto out;
582	}
583
584	if (!avb_chain_partition_descriptor_validate_and_byteswap(
585	(AvbChainPartitionDescriptor*)descriptors[n], &chain_desc)) {
586	avb_errorv(full_partition_name,
587	": Chain partition descriptor is invalid.\n",
588	NULL);
589	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
590	goto out;
591	}
592
593	if (chain_desc.rollback_index_location == 0) {
594	avb_errorv(full_partition_name,
595	": Chain partition has invalid "
596	"rollback_index_location field.\n",
597	NULL);
598	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
599	goto out;
600	}
601
602	chain_partition_name = ((const uint8_t*)descriptors[n]) +
603	sizeof(AvbChainPartitionDescriptor);
604	chain_public_key = chain_partition_name + chain_desc.partition_name_len;
605
606	sub_ret = load_and_verify_vbmeta(ops,
607	requested_partitions,
608	ab_suffix,
609	allow_verification_error,
610	toplevel_vbmeta_flags,
611	chain_desc.rollback_index_location,
612	(const char*)chain_partition_name,
613	chain_desc.partition_name_len,
614	chain_public_key,
615	chain_desc.public_key_len,
616	slot_data,
617	NULL /* out_algorithm_type */);
618	if (sub_ret != AVB_SLOT_VERIFY_RESULT_OK) {
619	ret = sub_ret;
620	if (!result_should_continue(ret)) {
621	goto out;
622	}
623	}
624	} break;
625
626	case AVB_DESCRIPTOR_TAG_KERNEL_CMDLINE: {
627	const uint8_t* kernel_cmdline;
628	AvbKernelCmdlineDescriptor kernel_cmdline_desc;
629	bool apply_cmdline;
630
631	if (!avb_kernel_cmdline_descriptor_validate_and_byteswap(
632	(AvbKernelCmdlineDescriptor*)descriptors[n],
633	&kernel_cmdline_desc)) {
634	avb_errorv(full_partition_name,
635	": Kernel cmdline descriptor is invalid.\n",
636	NULL);
637	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
638	goto out;
639	}
640
641	kernel_cmdline = ((const uint8_t*)descriptors[n]) +
642	sizeof(AvbKernelCmdlineDescriptor);
643
644	if (!avb_validate_utf8(kernel_cmdline,
645	kernel_cmdline_desc.kernel_cmdline_length)) {
646	avb_errorv(full_partition_name,
647	": Kernel cmdline is not valid UTF-8.\n",
648	NULL);
649	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
650	goto out;
651	}
652
653	/* Compare the flags for top-level VBMeta struct with flags in
654	* the command-line descriptor so command-line snippets only
655	* intended for a certain mode (dm-verity enabled/disabled)
656	* are skipped if applicable.
657	*/
658	apply_cmdline = true;
659	if (toplevel_vbmeta_flags & AVB_VBMETA_IMAGE_FLAGS_HASHTREE_DISABLED) {
660	if (kernel_cmdline_desc.flags &
661	AVB_KERNEL_CMDLINE_FLAGS_USE_ONLY_IF_HASHTREE_NOT_DISABLED) {
662	apply_cmdline = false;
663	}
664	} else {
665	if (kernel_cmdline_desc.flags &
666	AVB_KERNEL_CMDLINE_FLAGS_USE_ONLY_IF_HASHTREE_DISABLED) {
667	apply_cmdline = false;
668	}
669	}
670
671	if (apply_cmdline) {
672	if (slot_data->cmdline == NULL) {
673	slot_data->cmdline =
674	avb_calloc(kernel_cmdline_desc.kernel_cmdline_length + 1);
675	if (slot_data->cmdline == NULL) {
676	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
677	goto out;
678	}
679	avb_memcpy(slot_data->cmdline,
680	kernel_cmdline,
681	kernel_cmdline_desc.kernel_cmdline_length);
682	} else {
683	/* new cmdline is: <existing_cmdline> + ' ' + <newcmdline> + '\0' */
684	size_t orig_size = avb_strlen(slot_data->cmdline);
685	size_t new_size =
686	orig_size + 1 + kernel_cmdline_desc.kernel_cmdline_length + 1;
687	char* new_cmdline = avb_calloc(new_size);
688	if (new_cmdline == NULL) {
689	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
690	goto out;
691	}
692	avb_memcpy(new_cmdline, slot_data->cmdline, orig_size);
693	new_cmdline[orig_size] = ' ';
694	avb_memcpy(new_cmdline + orig_size + 1,
695	kernel_cmdline,
696	kernel_cmdline_desc.kernel_cmdline_length);
697	avb_free(slot_data->cmdline);
698	slot_data->cmdline = new_cmdline;
699	}
700	}
701	} break;
702
703	/* Explicit fall-through */
704	case AVB_DESCRIPTOR_TAG_PROPERTY:
705	case AVB_DESCRIPTOR_TAG_HASHTREE:
706	/* Do nothing. */
707	break;
708	}
709	}
710
711	if (rollback_index_location >= AVB_MAX_NUMBER_OF_ROLLBACK_INDEX_LOCATIONS) {
712	avb_errorv(
713	full_partition_name, ": Invalid rollback_index_location.\n", NULL);
714	ret = AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA;
715	goto out;
716	}
717
718	slot_data->rollback_indexes[rollback_index_location] =
719	vbmeta_header.rollback_index;
720
721	if (out_algorithm_type != NULL) {
722	*out_algorithm_type = (AvbAlgorithmType)vbmeta_header.algorithm_type;
723	}
724
725	out:
726	/* If |vbmeta_image_data| isn't NULL it means that it adopted
727	* |vbmeta_buf| so in that case don't free it here.
728	*/
729	if (vbmeta_image_data == NULL) {
730	if (vbmeta_buf != NULL) {
731	avb_free(vbmeta_buf);
732	}
733	}
734	if (descriptors != NULL) {
735	avb_free(descriptors);
736	}
737	return ret;
738	}
739
740	#define NUM_GUIDS 3
741
742	/* Substitutes all variables (e.g. $(ANDROID_SYSTEM_PARTUUID)) with
743	* values. Returns NULL on OOM, otherwise the cmdline with values
744	* replaced.
745	*/
746	static char* sub_cmdline(AvbOps* ops,
747	const char* cmdline,
748	const char* ab_suffix,
749	bool using_boot_for_vbmeta) {
750	const char* part_name_str[NUM_GUIDS] = {"system", "boot", "vbmeta"};
751	const char* replace_str[NUM_GUIDS] = {"$(ANDROID_SYSTEM_PARTUUID)",
752	"$(ANDROID_BOOT_PARTUUID)",
753	"$(ANDROID_VBMETA_PARTUUID)"};
754	char* ret = NULL;
755	AvbIOResult io_ret;
756
757	/* Special-case for when the top-level vbmeta struct is in the boot
758	* partition.
759	*/
760	if (using_boot_for_vbmeta) {
761	part_name_str[2] = "boot";
762	}
763
764	/* Replace unique partition GUIDs */
765	for (size_t n = 0; n < NUM_GUIDS; n++) {
766	char part_name[PART_NAME_MAX_SIZE];
767	char guid_buf[37];
768
769	if (!avb_str_concat(part_name,
770	sizeof part_name,
771	part_name_str[n],
772	avb_strlen(part_name_str[n]),
773	ab_suffix,
774	avb_strlen(ab_suffix))) {
775	avb_error("Partition name and suffix does not fit.\n");
776	goto fail;
777	}
778
779	io_ret = ops->get_unique_guid_for_partition(
780	ops, part_name, guid_buf, sizeof guid_buf);
781	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
782	return NULL;
783	} else if (io_ret != AVB_IO_RESULT_OK) {
784	avb_error("Error getting unique GUID for partition.\n");
785	goto fail;
786	}
787
788	if (ret == NULL) {
789	ret = avb_replace(cmdline, replace_str[n], guid_buf);
790	} else {
791	char* new_ret = avb_replace(ret, replace_str[n], guid_buf);
792	avb_free(ret);
793	ret = new_ret;
794	}
795	if (ret == NULL) {
796	goto fail;
797	}
798	}
799
800	return ret;
801
802	fail:
803	if (ret != NULL) {
804	avb_free(ret);
805	}
806	return NULL;
807	}
808
809	static int cmdline_append_option(AvbSlotVerifyData* slot_data,
810	const char* key,
811	const char* value) {
812	size_t offset, key_len, value_len;
813	char* new_cmdline;
814
815	key_len = avb_strlen(key);
816	value_len = avb_strlen(value);
817
818	offset = 0;
819	if (slot_data->cmdline != NULL) {
820	offset = avb_strlen(slot_data->cmdline);
821	if (offset > 0) {
822	offset += 1;
823	}
824	}
825
826	new_cmdline = avb_calloc(offset + key_len + value_len + 2);
827	if (new_cmdline == NULL) {
828	return 0;
829	}
830	if (offset > 0) {
831	avb_memcpy(new_cmdline, slot_data->cmdline, offset - 1);
832	new_cmdline[offset - 1] = ' ';
833	}
834	avb_memcpy(new_cmdline + offset, key, key_len);
835	new_cmdline[offset + key_len] = '=';
836	avb_memcpy(new_cmdline + offset + key_len + 1, value, value_len);
837	if (slot_data->cmdline != NULL) {
838	avb_free(slot_data->cmdline);
839	}
840	slot_data->cmdline = new_cmdline;
841
842	return 1;
843	}
844
845	#define AVB_MAX_DIGITS_UINT64 32
846
847	/* Writes |value| to |digits| in base 10 followed by a NUL byte.
848	* Returns number of characters written excluding the NUL byte.
849	*/
850	static size_t uint64_to_base10(uint64_t value,
851	char digits[AVB_MAX_DIGITS_UINT64]) {
852	char rev_digits[AVB_MAX_DIGITS_UINT64];
853	size_t n, num_digits;
854
855	for (num_digits = 0; num_digits < AVB_MAX_DIGITS_UINT64 - 1;) {
856	rev_digits[num_digits++] = (value % 10) + '0';
857	value /= 10;
858	if (value == 0) {
859	break;
860	}
861	}
862
863	for (n = 0; n < num_digits; n++) {
864	digits[n] = rev_digits[num_digits - 1 - n];
865	}
866	digits[n] = '\0';
867	return n;
868	}
869
870	static int cmdline_append_version(AvbSlotVerifyData* slot_data,
871	const char* key,
872	uint64_t major_version,
873	uint64_t minor_version) {
874	char major_digits[AVB_MAX_DIGITS_UINT64];
875	char minor_digits[AVB_MAX_DIGITS_UINT64];
876	char combined[AVB_MAX_DIGITS_UINT64 * 2 + 1];
877	size_t num_major_digits, num_minor_digits;
878
879	num_major_digits = uint64_to_base10(major_version, major_digits);
880	num_minor_digits = uint64_to_base10(minor_version, minor_digits);
881	avb_memcpy(combined, major_digits, num_major_digits);
882	combined[num_major_digits] = '.';
883	avb_memcpy(combined + num_major_digits + 1, minor_digits, num_minor_digits);
884	combined[num_major_digits + 1 + num_minor_digits] = '\0';
885
886	return cmdline_append_option(slot_data, key, combined);
887	}
888
889	static int cmdline_append_uint64_base10(AvbSlotVerifyData* slot_data,
890	const char* key,
891	uint64_t value) {
892	char digits[AVB_MAX_DIGITS_UINT64];
893	uint64_to_base10(value, digits);
894	return cmdline_append_option(slot_data, key, digits);
895	}
896
897	static int cmdline_append_hex(AvbSlotVerifyData* slot_data,
898	const char* key,
899	const uint8_t* data,
900	size_t data_len) {
901	char hex_digits[17] = "0123456789abcdef";
902	char* hex_data;
903	int ret;
904	size_t n;
905
906	hex_data = avb_malloc(data_len * 2 + 1);
907	if (hex_data == NULL) {
908	return 0;
909	}
910
911	for (n = 0; n < data_len; n++) {
912	hex_data[n * 2] = hex_digits[data[n] >> 4];
913	hex_data[n * 2 + 1] = hex_digits[data[n] & 0x0f];
914	}
915	hex_data[n * 2] = '\0';
916
917	ret = cmdline_append_option(slot_data, key, hex_data);
918	avb_free(hex_data);
919	return ret;
920	}
921
922	AvbSlotVerifyResult avb_slot_verify(AvbOps* ops,
923	const char* const* requested_partitions,
924	const char* ab_suffix,
925	bool allow_verification_error,
926	AvbSlotVerifyData** out_data) {
927	AvbSlotVerifyResult ret;
928	AvbSlotVerifyData* slot_data = NULL;
929	AvbAlgorithmType algorithm_type = AVB_ALGORITHM_TYPE_NONE;
930	AvbIOResult io_ret;
931	bool using_boot_for_vbmeta = false;
932
933	if (out_data != NULL) {
934	*out_data = NULL;
935	}
936
937	slot_data = avb_calloc(sizeof(AvbSlotVerifyData));
938	if (slot_data == NULL) {
939	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
940	goto fail;
941	}
942	slot_data->vbmeta_images =
943	avb_calloc(sizeof(AvbVBMetaData) * MAX_NUMBER_OF_VBMETA_IMAGES);
944	if (slot_data->vbmeta_images == NULL) {
945	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
946	goto fail;
947	}
948	slot_data->loaded_partitions =
949	avb_calloc(sizeof(AvbPartitionData) * MAX_NUMBER_OF_LOADED_PARTITIONS);
950	if (slot_data->loaded_partitions == NULL) {
951	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
952	goto fail;
953	}
954
955	ret = load_and_verify_vbmeta(ops,
956	requested_partitions,
957	ab_suffix,
958	allow_verification_error,
959	0 /* toplevel_vbmeta_flags */,
960	0 /* rollback_index_location */,
961	"vbmeta",
962	avb_strlen("vbmeta"),
963	NULL /* expected_public_key */,
964	0 /* expected_public_key_length */,
965	slot_data,
966	&algorithm_type);
967	if (!allow_verification_error && ret != AVB_SLOT_VERIFY_RESULT_OK) {
968	goto fail;
969	}
970
971	if (avb_strcmp(slot_data->vbmeta_images[0].partition_name, "vbmeta") != 0) {
972	avb_assert(avb_strcmp(slot_data->vbmeta_images[0].partition_name, "boot") ==
973	0);
974	using_boot_for_vbmeta = true;
975	}
976
977	/* If things check out, mangle the kernel command-line as needed. */
978	if (result_should_continue(ret)) {
979	/* Fill in |ab_suffix| field. */
980	slot_data->ab_suffix = avb_strdup(ab_suffix);
981	if (slot_data->ab_suffix == NULL) {
982	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
983	goto fail;
984	}
985
986	/* Add androidboot.vbmeta.device option. */
987	if (!cmdline_append_option(slot_data,
988	"androidboot.vbmeta.device",
989	"PARTUUID=$(ANDROID_VBMETA_PARTUUID)")) {
990	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
991	goto fail;
992	}
993
994	/* Add androidboot.vbmeta.avb_version option. */
995	if (!cmdline_append_version(slot_data,
996	"androidboot.vbmeta.avb_version",
997	AVB_VERSION_MAJOR,
998	AVB_VERSION_MINOR)) {
999	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1000	goto fail;
1001	}
1002
1003	/* Substitute $(ANDROID_SYSTEM_PARTUUID) and friends. */
1004	if (slot_data->cmdline != NULL) {
1005	char* new_cmdline;
1006	new_cmdline = sub_cmdline(
1007	ops, slot_data->cmdline, ab_suffix, using_boot_for_vbmeta);
1008	if (new_cmdline == NULL) {
1009	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1010	goto fail;
1011	}
1012	avb_free(slot_data->cmdline);
1013	slot_data->cmdline = new_cmdline;
1014	}
1015
1016	/* Set androidboot.avb.device_state to "locked" or "unlocked". */
1017	bool is_device_unlocked;
1018	io_ret = ops->read_is_device_unlocked(ops, &is_device_unlocked);
1019	if (io_ret == AVB_IO_RESULT_ERROR_OOM) {
1020	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1021	goto fail;
1022	} else if (io_ret != AVB_IO_RESULT_OK) {
1023	avb_error("Error getting device state.\n");
1024	ret = AVB_SLOT_VERIFY_RESULT_ERROR_IO;
1025	goto fail;
1026	}
1027	if (!cmdline_append_option(slot_data,
1028	"androidboot.vbmeta.device_state",
1029	is_device_unlocked ? "unlocked" : "locked")) {
1030	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1031	goto fail;
1032	}
1033
1034	/* Set androidboot.vbmeta.{hash_alg, size, digest} - use same hash
1035	* function as is used to sign vbmeta.
1036	*/
1037	switch (algorithm_type) {
1038	/* Explicit fallthrough. */
1039	case AVB_ALGORITHM_TYPE_NONE:
1040	case AVB_ALGORITHM_TYPE_SHA256_RSA2048:
1041	case AVB_ALGORITHM_TYPE_SHA256_RSA4096:
1042	case AVB_ALGORITHM_TYPE_SHA256_RSA8192: {
1043	AvbSHA256Ctx ctx;
1044	size_t n, total_size = 0;
1045	avb_sha256_init(&ctx);
1046	for (n = 0; n < slot_data->num_vbmeta_images; n++) {
1047	avb_sha256_update(&ctx,
1048	slot_data->vbmeta_images[n].vbmeta_data,
1049	slot_data->vbmeta_images[n].vbmeta_size);
1050	total_size += slot_data->vbmeta_images[n].vbmeta_size;
1051	}
1052	if (!cmdline_append_option(
1053	slot_data, "androidboot.vbmeta.hash_alg", "sha256") ||
1054	!cmdline_append_uint64_base10(
1055	slot_data, "androidboot.vbmeta.size", total_size) ||
1056	!cmdline_append_hex(slot_data,
1057	"androidboot.vbmeta.digest",
1058	avb_sha256_final(&ctx),
1059	AVB_SHA256_DIGEST_SIZE)) {
1060	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1061	goto fail;
1062	}
1063	} break;
1064	/* Explicit fallthrough. */
1065	case AVB_ALGORITHM_TYPE_SHA512_RSA2048:
1066	case AVB_ALGORITHM_TYPE_SHA512_RSA4096:
1067	case AVB_ALGORITHM_TYPE_SHA512_RSA8192: {
1068	AvbSHA512Ctx ctx;
1069	size_t n, total_size = 0;
1070	avb_sha512_init(&ctx);
1071	for (n = 0; n < slot_data->num_vbmeta_images; n++) {
1072	avb_sha512_update(&ctx,
1073	slot_data->vbmeta_images[n].vbmeta_data,
1074	slot_data->vbmeta_images[n].vbmeta_size);
1075	total_size += slot_data->vbmeta_images[n].vbmeta_size;
1076	}
1077	if (!cmdline_append_option(
1078	slot_data, "androidboot.vbmeta.hash_alg", "sha512") ||
1079	!cmdline_append_uint64_base10(
1080	slot_data, "androidboot.vbmeta.size", total_size) ||
1081	!cmdline_append_hex(slot_data,
1082	"androidboot.vbmeta.digest",
1083	avb_sha512_final(&ctx),
1084	AVB_SHA512_DIGEST_SIZE)) {
1085	ret = AVB_SLOT_VERIFY_RESULT_ERROR_OOM;
1086	goto fail;
1087	}
1088	} break;
1089	case _AVB_ALGORITHM_NUM_TYPES:
1090	avb_assert_not_reached();
1091	break;
1092	}
1093
1094	if (out_data != NULL) {
1095	*out_data = slot_data;
1096	} else {
1097	avb_slot_verify_data_free(slot_data);
1098	}
1099	}
1100
1101	if (!allow_verification_error) {
1102	avb_assert(ret == AVB_SLOT_VERIFY_RESULT_OK);
1103	}
1104
1105	return ret;
1106
1107	fail:
1108	if (slot_data != NULL) {
1109	avb_slot_verify_data_free(slot_data);
1110	}
1111	return ret;
1112	}
1113
1114	void avb_slot_verify_data_free(AvbSlotVerifyData* data) {
1115	if (data->ab_suffix != NULL) {
1116	avb_free(data->ab_suffix);
1117	}
1118	if (data->cmdline != NULL) {
1119	avb_free(data->cmdline);
1120	}
1121	if (data->vbmeta_images != NULL) {
1122	size_t n;
1123	for (n = 0; n < data->num_vbmeta_images; n++) {
1124	AvbVBMetaData* vbmeta_image = &data->vbmeta_images[n];
1125	if (vbmeta_image->partition_name != NULL) {
1126	avb_free(vbmeta_image->partition_name);
1127	}
1128	if (vbmeta_image->vbmeta_data != NULL) {
1129	avb_free(vbmeta_image->vbmeta_data);
1130	}
1131	}
1132	avb_free(data->vbmeta_images);
1133	}
1134	if (data->loaded_partitions != NULL) {
1135	size_t n;
1136	for (n = 0; n < data->num_loaded_partitions; n++) {
1137	AvbPartitionData* loaded_partition = &data->loaded_partitions[n];
1138	if (loaded_partition->partition_name != NULL) {
1139	avb_free(loaded_partition->partition_name);
1140	}
1141	if (loaded_partition->data != NULL) {
1142	avb_free(loaded_partition->data);
1143	}
1144	}
1145	avb_free(data->loaded_partitions);
1146	}
1147	avb_free(data);
1148	}
1149
1150	const char* avb_slot_verify_result_to_string(AvbSlotVerifyResult result) {
1151	const char* ret = NULL;
1152
1153	switch (result) {
1154	case AVB_SLOT_VERIFY_RESULT_OK:
1155	ret = "OK";
1156	break;
1157	case AVB_SLOT_VERIFY_RESULT_ERROR_OOM:
1158	ret = "ERROR_OOM";
1159	break;
1160	case AVB_SLOT_VERIFY_RESULT_ERROR_IO:
1161	ret = "ERROR_IO";
1162	break;
1163	case AVB_SLOT_VERIFY_RESULT_ERROR_VERIFICATION:
1164	ret = "ERROR_VERIFICATION";
1165	break;
1166	case AVB_SLOT_VERIFY_RESULT_ERROR_ROLLBACK_INDEX:
1167	ret = "ERROR_ROLLBACK_INDEX";
1168	break;
1169	case AVB_SLOT_VERIFY_RESULT_ERROR_PUBLIC_KEY_REJECTED:
1170	ret = "ERROR_PUBLIC_KEY_REJECTED";
1171	break;
1172	case AVB_SLOT_VERIFY_RESULT_ERROR_INVALID_METADATA:
1173	ret = "ERROR_INVALID_METADATA";
1174	break;
1175	case AVB_SLOT_VERIFY_RESULT_ERROR_UNSUPPORTED_VERSION:
1176	ret = "ERROR_UNSUPPORTED_VERSION";
1177	break;
1178	/* Do not add a 'default:' case here because of -Wswitch. */
1179	}
1180
1181	if (ret == NULL) {
1182	avb_error("Unknown AvbSlotVerifyResult value.\n");
1183	ret = "(unknown)";
1184	}
1185
1186	return ret;
1187	}
1188