/*
   * 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 <u-boot/rsa.h>
  #include <u-boot/rsa-checksum.h>

  #define IMAGE_MAX_HASHED_NODES		100

  #ifdef USE_HOSTCC

  void *host_blob;
  void image_set_host_blob(void *blob)

  {

  	host_blob = blob;
  }
  void *image_get_host_blob(void)
  {
  	return host_blob;

  }
  #endif
  
  struct checksum_algo checksum_algos[] = {
  	{

  		.name = "sha1",
  		.checksum_len = SHA1_SUM_LEN,
  		.der_len = SHA1_DER_LEN,
  		.der_prefix = sha1_der_prefix,

  #if IMAGE_ENABLE_SIGN

  		.calculate_sign = EVP_sha1,

  #endif

  		.calculate = hash_calculate,

  	},
  	{

  		.name = "sha256",
  		.checksum_len = SHA256_SUM_LEN,
  		.der_len = SHA256_DER_LEN,
  		.der_prefix = sha256_der_prefix,

  #if IMAGE_ENABLE_SIGN

  		.calculate_sign = EVP_sha256,

  #endif

  		.calculate = hash_calculate,

  	}
  
  };
  
  struct crypto_algo crypto_algos[] = {
  	{

  		.name = "rsa2048",
  		.key_len = RSA2048_BYTES,
  		.sign = rsa_sign,
  		.add_verify_data = rsa_add_verify_data,
  		.verify = rsa_verify,

  	},
  	{

  		.name = "rsa4096",
  		.key_len = RSA4096_BYTES,
  		.sign = rsa_sign,
  		.add_verify_data = rsa_add_verify_data,
  		.verify = rsa_verify,

  	}

  };

  struct checksum_algo *image_get_checksum_algo(const char *full_name)
  {
  	int i;
  	const char *name;
  
  	for (i = 0; i < ARRAY_SIZE(checksum_algos); i++) {
  		name = checksum_algos[i].name;
  		/* Make sure names match and next char is a comma */
  		if (!strncmp(name, full_name, strlen(name)) &&
  		    full_name[strlen(name)] == ',')
  			return &checksum_algos[i];

  	}

  	return NULL;
  }

  struct crypto_algo *image_get_crypto_algo(const char *full_name)

  {
  	int i;

  	const char *name;
  
  	/* Move name to after the comma */
  	name = strchr(full_name, ',');
  	if (!name)
  		return NULL;
  	name += 1;

  	for (i = 0; i < ARRAY_SIZE(crypto_algos); i++) {
  		if (!strcmp(crypto_algos[i].name, name))
  			return &crypto_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:
  ");
  	debug("%10s %10s
  ", "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
  ", 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->name = algo_name;
  	info->checksum = image_get_checksum_algo(algo_name);
  	info->crypto = image_get_crypto_algo(algo_name);

  	info->fdt_blob = gd_fdt_blob();
  	info->required_keynode = required_keynode;
  	printf("%s:%s", algo_name, info->keyname);

  	if (!info->checksum || !info->crypto) {

  		*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.crypto->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 */

  	fdt_for_each_subnode(noffset, fit, image_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!
  %s for '%s' hash node in '%s' image node
  ",
  	       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
  ", __func__,
  		      fdt_strerror(sig_node));
  		return 0;
  	}

  	fdt_for_each_subnode(noffset, sig_blob, sig_node) {

  		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'
  ",
  			       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'
  ", __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):
  ", count);
  	for (name = prop, i = 0; name < end; name += strlen(name) + 1, i++) {
  		debug("   '%s'
  ", 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.crypto->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 */

  	fdt_for_each_subnode(noffset, fit, conf_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!
  %s for '%s' hash node in '%s' config node
  ",
  	       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
  ", __func__,
  		      fdt_strerror(sig_node));
  		return 0;
  	}

  	fdt_for_each_subnode(noffset, sig_blob, sig_node) {

  		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'
  ",
  			       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());

  }