[J-u-boot.git] / common / image-sig.c

/*
 * Copyright (c) 2013, Google Inc.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#ifdef USE_HOSTCC
#include "mkimage.h"
#include <time.h>
#else
#include <common.h>
#include <malloc.h>
DECLARE_GLOBAL_DATA_PTR;
#endif /* !USE_HOSTCC*/
#include <image.h>
#include <rsa.h>

#define IMAGE_MAX_HASHED_NODES		100

struct image_sig_algo image_sig_algos[] = {
	{
		"sha1,rsa2048",
		rsa_sign,
		rsa_add_verify_data,
		rsa_verify,
	}
};

struct image_sig_algo *image_get_sig_algo(const char *name)
{
	int i;

	for (i = 0; i < ARRAY_SIZE(image_sig_algos); i++) {
		if (!strcmp(image_sig_algos[i].name, name))
			return &image_sig_algos[i];
	}

	return NULL;
}

/**
 * fit_region_make_list() - Make a list of image regions
 *
 * Given a list of fdt_regions, create a list of image_regions. This is a
 * simple conversion routine since the FDT and image code use different
 * structures.
 *
 * @fit: FIT image
 * @fdt_regions: Pointer to FDT regions
 * @count: Number of FDT regions
 * @region: Pointer to image regions, which must hold @count records. If
 * region is NULL, then (except for an SPL build) the array will be
 * allocated.
 * @return: Pointer to image regions
 */
struct image_region *fit_region_make_list(const void *fit,
		struct fdt_region *fdt_regions, int count,
		struct image_region *region)
{
	int i;

	debug("Hash regions:\n");
	debug("%10s %10s\n", "Offset", "Size");

	/*
	 * Use malloc() except in SPL (to save code size). In SPL the caller
	 * must allocate the array.
	 */
#ifndef CONFIG_SPL_BUILD
	if (!region)
		region = calloc(sizeof(*region), count);
#endif
	if (!region)
		return NULL;
	for (i = 0; i < count; i++) {
		debug("%10x %10x\n", fdt_regions[i].offset,
		      fdt_regions[i].size);
		region[i].data = fit + fdt_regions[i].offset;
		region[i].size = fdt_regions[i].size;
	}

	return region;
}

static int fit_image_setup_verify(struct image_sign_info *info,
		const void *fit, int noffset, int required_keynode,
		char **err_msgp)
{
	char *algo_name;

	if (fit_image_hash_get_algo(fit, noffset, &algo_name)) {
		*err_msgp = "Can't get hash algo property";
		return -1;
	}
	memset(info, '\0', sizeof(*info));
	info->keyname = fdt_getprop(fit, noffset, "key-name-hint", NULL);
	info->fit = (void *)fit;
	info->node_offset = noffset;
	info->algo = image_get_sig_algo(algo_name);
	info->fdt_blob = gd_fdt_blob();
	info->required_keynode = required_keynode;
	printf("%s:%s", algo_name, info->keyname);

	if (!info->algo) {
		*err_msgp = "Unknown signature algorithm";
		return -1;
	}

	return 0;
}

int fit_image_check_sig(const void *fit, int noffset, const void *data,
		size_t size, int required_keynode, char **err_msgp)
{
	struct image_sign_info info;
	struct image_region region;
	uint8_t *fit_value;
	int fit_value_len;

	*err_msgp = NULL;
	if (fit_image_setup_verify(&info, fit, noffset, required_keynode,
				   err_msgp))
		return -1;

	if (fit_image_hash_get_value(fit, noffset, &fit_value,
				     &fit_value_len)) {
		*err_msgp = "Can't get hash value property";
		return -1;
	}

	region.data = data;
	region.size = size;

	if (info.algo->verify(&info, &region, 1, fit_value, fit_value_len)) {
		*err_msgp = "Verification failed";
		return -1;
	}

	return 0;
}

static int fit_image_verify_sig(const void *fit, int image_noffset,
		const char *data, size_t size, const void *sig_blob,
		int sig_offset)
{
	int noffset;
	char *err_msg = "";
	int verified = 0;
	int ret;

	/* Process all hash subnodes of the component image node */
	for (noffset = fdt_first_subnode(fit, image_noffset);
	     noffset >= 0;
	     noffset = fdt_next_subnode(fit, noffset)) {
		const char *name = fit_get_name(fit, noffset, NULL);

		if (!strncmp(name, FIT_SIG_NODENAME,
			     strlen(FIT_SIG_NODENAME))) {
			ret = fit_image_check_sig(fit, noffset, data,
							size, -1, &err_msg);
			if (ret) {
				puts("- ");
			} else {
				puts("+ ");
				verified = 1;
				break;
			}
		}
	}

	if (noffset == -FDT_ERR_TRUNCATED || noffset == -FDT_ERR_BADSTRUCTURE) {
		err_msg = "Corrupted or truncated tree";
		goto error;
	}

	return verified ? 0 : -EPERM;

error:
	printf(" error!\n%s for '%s' hash node in '%s' image node\n",
	       err_msg, fit_get_name(fit, noffset, NULL),
	       fit_get_name(fit, image_noffset, NULL));
	return -1;
}

int fit_image_verify_required_sigs(const void *fit, int image_noffset,
		const char *data, size_t size, const void *sig_blob,
		int *no_sigsp)
{
	int verify_count = 0;
	int noffset;
	int sig_node;

	/* Work out what we need to verify */
	*no_sigsp = 1;
	sig_node = fdt_subnode_offset(sig_blob, 0, FIT_SIG_NODENAME);
	if (sig_node < 0) {
		debug("%s: No signature node found: %s\n", __func__,
		      fdt_strerror(sig_node));
		return 0;
	}

	for (noffset = fdt_first_subnode(sig_blob, sig_node);
	     noffset >= 0;
	     noffset = fdt_next_subnode(sig_blob, noffset)) {
		const char *required;
		int ret;

		required = fdt_getprop(sig_blob, noffset, "required", NULL);
		if (!required || strcmp(required, "image"))
			continue;
		ret = fit_image_verify_sig(fit, image_noffset, data, size,
					sig_blob, noffset);
		if (ret) {
			printf("Failed to verify required signature '%s'\n",
			       fit_get_name(sig_blob, noffset, NULL));
			return ret;
		}
		verify_count++;
	}

	if (verify_count)
		*no_sigsp = 0;

	return 0;
}

int fit_config_check_sig(const void *fit, int noffset, int required_keynode,
			 char **err_msgp)
{
	char * const exc_prop[] = {"data"};
	const char *prop, *end, *name;
	struct image_sign_info info;
	const uint32_t *strings;
	uint8_t *fit_value;
	int fit_value_len;
	int max_regions;
	int i, prop_len;
	char path[200];
	int count;

	debug("%s: fdt=%p, conf='%s', sig='%s'\n", __func__, gd_fdt_blob(),
	      fit_get_name(fit, noffset, NULL),
	      fit_get_name(gd_fdt_blob(), required_keynode, NULL));
	*err_msgp = NULL;
	if (fit_image_setup_verify(&info, fit, noffset, required_keynode,
				   err_msgp))
		return -1;

	if (fit_image_hash_get_value(fit, noffset, &fit_value,
				     &fit_value_len)) {
		*err_msgp = "Can't get hash value property";
		return -1;
	}

	/* Count the number of strings in the property */
	prop = fdt_getprop(fit, noffset, "hashed-nodes", &prop_len);
	end = prop ? prop + prop_len : prop;
	for (name = prop, count = 0; name < end; name++)
		if (!*name)
			count++;
	if (!count) {
		*err_msgp = "Can't get hashed-nodes property";
		return -1;
	}

	/* Add a sanity check here since we are using the stack */
	if (count > IMAGE_MAX_HASHED_NODES) {
		*err_msgp = "Number of hashed nodes exceeds maximum";
		return -1;
	}

	/* Create a list of node names from those strings */
	char *node_inc[count];

	debug("Hash nodes (%d):\n", count);
	for (name = prop, i = 0; name < end; name += strlen(name) + 1, i++) {
		debug("   '%s'\n", name);
		node_inc[i] = (char *)name;
	}

	/*
	 * Each node can generate one region for each sub-node. Allow for
	 * 7 sub-nodes (hash@1, signature@1, etc.) and some extra.
	 */
	max_regions = 20 + count * 7;
	struct fdt_region fdt_regions[max_regions];

	/* Get a list of regions to hash */
	count = fdt_find_regions(fit, node_inc, count,
			exc_prop, ARRAY_SIZE(exc_prop),
			fdt_regions, max_regions - 1,
			path, sizeof(path), 0);
	if (count < 0) {
		*err_msgp = "Failed to hash configuration";
		return -1;
	}
	if (count == 0) {
		*err_msgp = "No data to hash";
		return -1;
	}
	if (count >= max_regions - 1) {
		*err_msgp = "Too many hash regions";
		return -1;
	}

	/* Add the strings */
	strings = fdt_getprop(fit, noffset, "hashed-strings", NULL);
	if (strings) {
		fdt_regions[count].offset = fdt_off_dt_strings(fit) +
				fdt32_to_cpu(strings[0]);
		fdt_regions[count].size = fdt32_to_cpu(strings[1]);
		count++;
	}

	/* Allocate the region list on the stack */
	struct image_region region[count];

	fit_region_make_list(fit, fdt_regions, count, region);
	if (info.algo->verify(&info, region, count, fit_value,
			      fit_value_len)) {
		*err_msgp = "Verification failed";
		return -1;
	}

	return 0;
}

static int fit_config_verify_sig(const void *fit, int conf_noffset,
		const void *sig_blob, int sig_offset)
{
	int noffset;
	char *err_msg = "";
	int verified = 0;
	int ret;

	/* Process all hash subnodes of the component conf node */
	for (noffset = fdt_first_subnode(fit, conf_noffset);
	     noffset >= 0;
	     noffset = fdt_next_subnode(fit, noffset)) {
		const char *name = fit_get_name(fit, noffset, NULL);

		if (!strncmp(name, FIT_SIG_NODENAME,
			     strlen(FIT_SIG_NODENAME))) {
			ret = fit_config_check_sig(fit, noffset, sig_offset,
						   &err_msg);
			if (ret) {
				puts("- ");
			} else {
				puts("+ ");
				verified = 1;
				break;
			}
		}
	}

	if (noffset == -FDT_ERR_TRUNCATED || noffset == -FDT_ERR_BADSTRUCTURE) {
		err_msg = "Corrupted or truncated tree";
		goto error;
	}

	return verified ? 0 : -EPERM;

error:
	printf(" error!\n%s for '%s' hash node in '%s' config node\n",
	       err_msg, fit_get_name(fit, noffset, NULL),
	       fit_get_name(fit, conf_noffset, NULL));
	return -1;
}

int fit_config_verify_required_sigs(const void *fit, int conf_noffset,
		const void *sig_blob)
{
	int noffset;
	int sig_node;

	/* Work out what we need to verify */
	sig_node = fdt_subnode_offset(sig_blob, 0, FIT_SIG_NODENAME);
	if (sig_node < 0) {
		debug("%s: No signature node found: %s\n", __func__,
		      fdt_strerror(sig_node));
		return 0;
	}

	for (noffset = fdt_first_subnode(sig_blob, sig_node);
	     noffset >= 0;
	     noffset = fdt_next_subnode(sig_blob, noffset)) {
		const char *required;
		int ret;

		required = fdt_getprop(sig_blob, noffset, "required", NULL);
		if (!required || strcmp(required, "conf"))
			continue;
		ret = fit_config_verify_sig(fit, conf_noffset, sig_blob,
					    noffset);
		if (ret) {
			printf("Failed to verify required signature '%s'\n",
			       fit_get_name(sig_blob, noffset, NULL));
			return ret;
		}
	}

	return 0;
}

int fit_config_verify(const void *fit, int conf_noffset)
{
	return !fit_config_verify_required_sigs(fit, conf_noffset,
						gd_fdt_blob());
}
Commit	Line	Data
3e569a6b SG	1	/*
	2	* Copyright (c) 2013, Google Inc.
	3	*
1a459660	4	* SPDX-License-Identifier: GPL-2.0+
3e569a6b SG	5	*/
	6
	7	#ifdef USE_HOSTCC
	8	#include "mkimage.h"
	9	#include <time.h>
	10	#else
	11	#include <common.h>
56518e71 SG	12	#include <malloc.h>
56518e71 SG	13	DECLARE_GLOBAL_DATA_PTR;
3e569a6b	14	#endif /* !USE_HOSTCC*/
3e569a6b	15	#include <image.h>
19c402af	16	#include <rsa.h>
3e569a6b	17
4d098529 SG	18	#define IMAGE_MAX_HASHED_NODES 100
4d098529 SG	19
3e569a6b	20	struct image_sig_algo image_sig_algos[] = {
19c402af SG	21	{
	22	"sha1,rsa2048",
	23	rsa_sign,
	24	rsa_add_verify_data,
	25	rsa_verify,
	26	}
3e569a6b SG	27	};
	28
	29	struct image_sig_algo image_get_sig_algo(const char name)
	30	{
	31	int i;
	32
	33	for (i = 0; i < ARRAY_SIZE(image_sig_algos); i++) {
	34	if (!strcmp(image_sig_algos[i].name, name))
	35	return &image_sig_algos[i];
	36	}
	37
	38	return NULL;
	39	}
56518e71	40
4d098529 SG	41	/**
	42	* fit_region_make_list() - Make a list of image regions
	43	*
	44	* Given a list of fdt_regions, create a list of image_regions. This is a
	45	* simple conversion routine since the FDT and image code use different
	46	* structures.
	47	*
	48	* @fit: FIT image
	49	* @fdt_regions: Pointer to FDT regions
	50	* @count: Number of FDT regions
	51	* @region: Pointer to image regions, which must hold @count records. If
	52	* region is NULL, then (except for an SPL build) the array will be
	53	* allocated.
	54	* @return: Pointer to image regions
	55	*/
	56	struct image_region fit_region_make_list(const void fit,
	57	struct fdt_region *fdt_regions, int count,
	58	struct image_region *region)
	59	{
	60	int i;
	61
	62	debug("Hash regions:\n");
	63	debug("%10s %10s\n", "Offset", "Size");
	64
	65	/*
	66	* Use malloc() except in SPL (to save code size). In SPL the caller
	67	* must allocate the array.
	68	*/
	69	#ifndef CONFIG_SPL_BUILD
	70	if (!region)
	71	region = calloc(sizeof(*region), count);
	72	#endif
	73	if (!region)
	74	return NULL;
	75	for (i = 0; i < count; i++) {
	76	debug("%10x %10x\n", fdt_regions[i].offset,
	77	fdt_regions[i].size);
	78	region[i].data = fit + fdt_regions[i].offset;
	79	region[i].size = fdt_regions[i].size;
	80	}
	81
	82	return region;
	83	}
	84
56518e71 SG	85	static int fit_image_setup_verify(struct image_sign_info *info,
	86	const void *fit, int noffset, int required_keynode,
	87	char **err_msgp)
	88	{
	89	char *algo_name;
	90
	91	if (fit_image_hash_get_algo(fit, noffset, &algo_name)) {
	92	*err_msgp = "Can't get hash algo property";
	93	return -1;
	94	}
	95	memset(info, '\0', sizeof(*info));
	96	info->keyname = fdt_getprop(fit, noffset, "key-name-hint", NULL);
	97	info->fit = (void *)fit;
	98	info->node_offset = noffset;
	99	info->algo = image_get_sig_algo(algo_name);
	100	info->fdt_blob = gd_fdt_blob();
	101	info->required_keynode = required_keynode;
	102	printf("%s:%s", algo_name, info->keyname);
	103
	104	if (!info->algo) {
	105	*err_msgp = "Unknown signature algorithm";
	106	return -1;
	107	}
	108
	109	return 0;
	110	}
	111
	112	int fit_image_check_sig(const void fit, int noffset, const void data,
	113	size_t size, int required_keynode, char **err_msgp)
	114	{
	115	struct image_sign_info info;
	116	struct image_region region;
	117	uint8_t *fit_value;
	118	int fit_value_len;
	119
	120	*err_msgp = NULL;
	121	if (fit_image_setup_verify(&info, fit, noffset, required_keynode,
	122	err_msgp))
	123	return -1;
	124
	125	if (fit_image_hash_get_value(fit, noffset, &fit_value,
	126	&fit_value_len)) {
	127	*err_msgp = "Can't get hash value property";
	128	return -1;
	129	}
	130
	131	region.data = data;
	132	region.size = size;
	133
	134	if (info.algo->verify(&info, &region, 1, fit_value, fit_value_len)) {
	135	*err_msgp = "Verification failed";
	136	return -1;
	137	}
	138
	139	return 0;
	140	}
	141
	142	static int fit_image_verify_sig(const void *fit, int image_noffset,
	143	const char data, size_t size, const void sig_blob,
	144	int sig_offset)
	145	{
	146	int noffset;
	147	char *err_msg = "";
	148	int verified = 0;
149	int ret;
150
151	/* Process all hash subnodes of the component image node */
152	for (noffset = fdt_first_subnode(fit, image_noffset);
153	noffset >= 0;
154	noffset = fdt_next_subnode(fit, noffset)) {
155	const char *name = fit_get_name(fit, noffset, NULL);
156
157	if (!strncmp(name, FIT_SIG_NODENAME,
158	strlen(FIT_SIG_NODENAME))) {
159	ret = fit_image_check_sig(fit, noffset, data,
160	size, -1, &err_msg);
161	if (ret) {
162	puts("- ");
163	} else {
164	puts("+ ");
165	verified = 1;
166	break;
167	}
168	}
169	}
170
171	if (noffset == -FDT_ERR_TRUNCATED \|\| noffset == -FDT_ERR_BADSTRUCTURE) {
172	err_msg = "Corrupted or truncated tree";
173	goto error;
174	}
175
176	return verified ? 0 : -EPERM;
177
178	error:
179	printf(" error!\n%s for '%s' hash node in '%s' image node\n",
180	err_msg, fit_get_name(fit, noffset, NULL),
181	fit_get_name(fit, image_noffset, NULL));
182	return -1;
183	}
184
185	int fit_image_verify_required_sigs(const void *fit, int image_noffset,
186	const char data, size_t size, const void sig_blob,
187	int *no_sigsp)
188	{
189	int verify_count = 0;
190	int noffset;
191	int sig_node;
192
193	/* Work out what we need to verify */
194	*no_sigsp = 1;
195	sig_node = fdt_subnode_offset(sig_blob, 0, FIT_SIG_NODENAME);
196	if (sig_node < 0) {
197	debug("%s: No signature node found: %s\n", __func__,
198	fdt_strerror(sig_node));
199	return 0;
200	}
201
202	for (noffset = fdt_first_subnode(sig_blob, sig_node);
203	noffset >= 0;
204	noffset = fdt_next_subnode(sig_blob, noffset)) {
205	const char *required;
206	int ret;
207
208	required = fdt_getprop(sig_blob, noffset, "required", NULL);
209	if (!required \|\| strcmp(required, "image"))
210	continue;
211	ret = fit_image_verify_sig(fit, image_noffset, data, size,
212	sig_blob, noffset);
213	if (ret) {
214	printf("Failed to verify required signature '%s'\n",
215	fit_get_name(sig_blob, noffset, NULL));
216	return ret;
217	}
218	verify_count++;
219	}
220
221	if (verify_count)
222	*no_sigsp = 0;
223
224	return 0;
225	}
4d098529 SG	226
	227	int fit_config_check_sig(const void *fit, int noffset, int required_keynode,
	228	char **err_msgp)
	229	{
	230	char * const exc_prop[] = {"data"};
	231	const char prop, end, *name;
	232	struct image_sign_info info;
	233	const uint32_t *strings;
	234	uint8_t *fit_value;
	235	int fit_value_len;
	236	int max_regions;
	237	int i, prop_len;
	238	char path[200];
	239	int count;
	240
	241	debug("%s: fdt=%p, conf='%s', sig='%s'\n", __func__, gd_fdt_blob(),
	242	fit_get_name(fit, noffset, NULL),
	243	fit_get_name(gd_fdt_blob(), required_keynode, NULL));
	244	*err_msgp = NULL;
	245	if (fit_image_setup_verify(&info, fit, noffset, required_keynode,
	246	err_msgp))
	247	return -1;
	248
	249	if (fit_image_hash_get_value(fit, noffset, &fit_value,
	250	&fit_value_len)) {
	251	*err_msgp = "Can't get hash value property";
	252	return -1;
	253	}
	254
	255	/* Count the number of strings in the property */
	256	prop = fdt_getprop(fit, noffset, "hashed-nodes", &prop_len);
	257	end = prop ? prop + prop_len : prop;
	258	for (name = prop, count = 0; name < end; name++)
	259	if (!*name)
	260	count++;
	261	if (!count) {
	262	*err_msgp = "Can't get hashed-nodes property";
	263	return -1;
	264	}
	265
	266	/* Add a sanity check here since we are using the stack */
	267	if (count > IMAGE_MAX_HASHED_NODES) {
	268	*err_msgp = "Number of hashed nodes exceeds maximum";
	269	return -1;
	270	}
	271
	272	/* Create a list of node names from those strings */
	273	char *node_inc[count];
	274
	275	debug("Hash nodes (%d):\n", count);
	276	for (name = prop, i = 0; name < end; name += strlen(name) + 1, i++) {
	277	debug(" '%s'\n", name);
	278	node_inc[i] = (char *)name;
	279	}
	280
	281	/*
	282	* Each node can generate one region for each sub-node. Allow for
	283	* 7 sub-nodes (hash@1, signature@1, etc.) and some extra.
	284	*/
	285	max_regions = 20 + count * 7;
	286	struct fdt_region fdt_regions[max_regions];
	287
	288	/* Get a list of regions to hash */
	289	count = fdt_find_regions(fit, node_inc, count,
290	exc_prop, ARRAY_SIZE(exc_prop),
291	fdt_regions, max_regions - 1,
292	path, sizeof(path), 0);
293	if (count < 0) {
294	*err_msgp = "Failed to hash configuration";
295	return -1;
296	}
297	if (count == 0) {
298	*err_msgp = "No data to hash";
299	return -1;
300	}
301	if (count >= max_regions - 1) {
302	*err_msgp = "Too many hash regions";
303	return -1;
304	}
305
306	/* Add the strings */
307	strings = fdt_getprop(fit, noffset, "hashed-strings", NULL);
308	if (strings) {
309	fdt_regions[count].offset = fdt_off_dt_strings(fit) +
310	fdt32_to_cpu(strings[0]);
311	fdt_regions[count].size = fdt32_to_cpu(strings[1]);
312	count++;
313	}
314
315	/* Allocate the region list on the stack */
316	struct image_region region[count];
317
318	fit_region_make_list(fit, fdt_regions, count, region);
319	if (info.algo->verify(&info, region, count, fit_value,
320	fit_value_len)) {
321	*err_msgp = "Verification failed";
322	return -1;
323	}
324
325	return 0;
326	}
327
328	static int fit_config_verify_sig(const void *fit, int conf_noffset,
329	const void *sig_blob, int sig_offset)
330	{
331	int noffset;
332	char *err_msg = "";
333	int verified = 0;
334	int ret;
335
336	/* Process all hash subnodes of the component conf node */
337	for (noffset = fdt_first_subnode(fit, conf_noffset);
338	noffset >= 0;
339	noffset = fdt_next_subnode(fit, noffset)) {
340	const char *name = fit_get_name(fit, noffset, NULL);
341
342	if (!strncmp(name, FIT_SIG_NODENAME,
343	strlen(FIT_SIG_NODENAME))) {
344	ret = fit_config_check_sig(fit, noffset, sig_offset,
345	&err_msg);
346	if (ret) {
347	puts("- ");
348	} else {
349	puts("+ ");
350	verified = 1;
351	break;
352	}
353	}
354	}
355
356	if (noffset == -FDT_ERR_TRUNCATED \|\| noffset == -FDT_ERR_BADSTRUCTURE) {
357	err_msg = "Corrupted or truncated tree";
358	goto error;
359	}
360
361	return verified ? 0 : -EPERM;
362
363	error:
364	printf(" error!\n%s for '%s' hash node in '%s' config node\n",
365	err_msg, fit_get_name(fit, noffset, NULL),
366	fit_get_name(fit, conf_noffset, NULL));
367	return -1;
368	}
369
370	int fit_config_verify_required_sigs(const void *fit, int conf_noffset,
371	const void *sig_blob)
372	{
373	int noffset;
374	int sig_node;
375
376	/* Work out what we need to verify */
377	sig_node = fdt_subnode_offset(sig_blob, 0, FIT_SIG_NODENAME);
378	if (sig_node < 0) {
379	debug("%s: No signature node found: %s\n", __func__,
380	fdt_strerror(sig_node));
381	return 0;
382	}
383
384	for (noffset = fdt_first_subnode(sig_blob, sig_node);
385	noffset >= 0;
386	noffset = fdt_next_subnode(sig_blob, noffset)) {
387	const char *required;
388	int ret;
389
390	required = fdt_getprop(sig_blob, noffset, "required", NULL);
391	if (!required \|\| strcmp(required, "conf"))
392	continue;
393	ret = fit_config_verify_sig(fit, conf_noffset, sig_blob,
394	noffset);
395	if (ret) {
396	printf("Failed to verify required signature '%s'\n",
397	fit_get_name(sig_blob, noffset, NULL));
398	return ret;
399	}
400	}
401
402	return 0;
403	}
404
405	int fit_config_verify(const void *fit, int conf_noffset)
406	{
407	return !fit_config_verify_required_sigs(fit, conf_noffset,
408	gd_fdt_blob());
409	}