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			770 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			770 lines
		
	
	
		
			26 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  The LMS stateful-hash public-key signature scheme
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|  *
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|  *  Copyright The Mbed TLS Contributors
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|  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
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|  */
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| 
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| /*
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|  *  The following sources were referenced in the design of this implementation
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|  *  of the LMS algorithm:
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|  *
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|  *  [1] IETF RFC8554
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|  *      D. McGrew, M. Curcio, S.Fluhrer
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|  *      https://datatracker.ietf.org/doc/html/rfc8554
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|  *
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|  *  [2] NIST Special Publication 800-208
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|  *      David A. Cooper et. al.
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|  *      https://nvlpubs.nist.gov/nistpubs/SpecialPublications/NIST.SP.800-208.pdf
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|  */
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| 
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| #include "common.h"
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| 
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| #if defined(MBEDTLS_LMS_C)
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| 
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| #include <string.h>
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| 
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| #include "lmots.h"
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| 
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| #include "psa/crypto.h"
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| #include "psa_util_internal.h"
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| #include "mbedtls/lms.h"
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| #include "mbedtls/error.h"
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| #include "mbedtls/platform_util.h"
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| 
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| #include "mbedtls/platform.h"
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| 
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| /* Define a local translating function to save code size by not using too many
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|  * arguments in each translating place. */
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| static int local_err_translation(psa_status_t status)
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| {
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|     return psa_status_to_mbedtls(status, psa_to_lms_errors,
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|                                  ARRAY_LENGTH(psa_to_lms_errors),
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|                                  psa_generic_status_to_mbedtls);
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| }
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| #define PSA_TO_MBEDTLS_ERR(status) local_err_translation(status)
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| 
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| #define SIG_Q_LEAF_ID_OFFSET     (0)
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| #define SIG_OTS_SIG_OFFSET       (SIG_Q_LEAF_ID_OFFSET + \
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|                                   MBEDTLS_LMOTS_Q_LEAF_ID_LEN)
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| #define SIG_TYPE_OFFSET(otstype) (SIG_OTS_SIG_OFFSET   + \
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|                                   MBEDTLS_LMOTS_SIG_LEN(otstype))
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| #define SIG_PATH_OFFSET(otstype) (SIG_TYPE_OFFSET(otstype) + \
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|                                   MBEDTLS_LMS_TYPE_LEN)
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| 
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| #define PUBLIC_KEY_TYPE_OFFSET      (0)
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| #define PUBLIC_KEY_OTSTYPE_OFFSET   (PUBLIC_KEY_TYPE_OFFSET + \
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|                                      MBEDTLS_LMS_TYPE_LEN)
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| #define PUBLIC_KEY_I_KEY_ID_OFFSET  (PUBLIC_KEY_OTSTYPE_OFFSET  + \
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|                                      MBEDTLS_LMOTS_TYPE_LEN)
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| #define PUBLIC_KEY_ROOT_NODE_OFFSET (PUBLIC_KEY_I_KEY_ID_OFFSET + \
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|                                      MBEDTLS_LMOTS_I_KEY_ID_LEN)
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| 
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| 
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| /* Currently only support H=10 */
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| #define H_TREE_HEIGHT_MAX                  10
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| #define MERKLE_TREE_NODE_AM(type)          ((size_t) 1 << (MBEDTLS_LMS_H_TREE_HEIGHT(type) + 1u))
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| #define MERKLE_TREE_LEAF_NODE_AM(type)     ((size_t) 1 << MBEDTLS_LMS_H_TREE_HEIGHT(type))
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| #define MERKLE_TREE_INTERNAL_NODE_AM(type) ((unsigned int) \
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|                                             (1u << MBEDTLS_LMS_H_TREE_HEIGHT(type)))
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| 
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| #define D_CONST_LEN           (2)
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| static const unsigned char D_LEAF_CONSTANT_BYTES[D_CONST_LEN] = { 0x82, 0x82 };
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| static const unsigned char D_INTR_CONSTANT_BYTES[D_CONST_LEN] = { 0x83, 0x83 };
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| 
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| 
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| /* Calculate the value of a leaf node of the Merkle tree (which is a hash of a
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|  * public key and some other parameters like the leaf index). This function
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|  * implements RFC8554 section 5.3, in the case where r >= 2^h.
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|  *
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|  *  params              The LMS parameter set, the underlying LMOTS
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|  *                      parameter set, and I value which describe the key
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|  *                      being used.
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|  *
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|  *  pub_key             The public key of the private whose index
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|  *                      corresponds to the index of this leaf node. This
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|  *                      is a hash output.
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|  *
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|  *  r_node_idx          The index of this node in the Merkle tree. Note
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|  *                      that the root node of the Merkle tree is
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|  *                      1-indexed.
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|  *
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|  *  out                 The output node value, which is a hash output.
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|  */
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| static int create_merkle_leaf_value(const mbedtls_lms_parameters_t *params,
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|                                     unsigned char *pub_key,
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|                                     unsigned int r_node_idx,
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|                                     unsigned char *out)
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| {
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|     psa_hash_operation_t op;
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|     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
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|     size_t output_hash_len;
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|     unsigned char r_node_idx_bytes[4];
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| 
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|     op = psa_hash_operation_init();
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|     status = psa_hash_setup(&op, PSA_ALG_SHA_256);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, params->I_key_identifier,
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|                              MBEDTLS_LMOTS_I_KEY_ID_LEN);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     MBEDTLS_PUT_UINT32_BE(r_node_idx, r_node_idx_bytes, 0);
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|     status = psa_hash_update(&op, r_node_idx_bytes, 4);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, D_LEAF_CONSTANT_BYTES, D_CONST_LEN);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, pub_key,
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|                              MBEDTLS_LMOTS_N_HASH_LEN(params->otstype));
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_finish(&op, out, MBEDTLS_LMS_M_NODE_BYTES(params->type),
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|                              &output_hash_len);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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| exit:
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|     psa_hash_abort(&op);
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| 
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|     return PSA_TO_MBEDTLS_ERR(status);
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| }
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| 
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| /* Calculate the value of an internal node of the Merkle tree (which is a hash
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|  * of a public key and some other parameters like the node index). This function
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|  * implements RFC8554 section 5.3, in the case where r < 2^h.
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|  *
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|  *  params              The LMS parameter set, the underlying LMOTS
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|  *                      parameter set, and I value which describe the key
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|  *                      being used.
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|  *
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|  *  left_node           The value of the child of this node which is on
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|  *                      the left-hand side. As with all nodes on the
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|  *                      Merkle tree, this is a hash output.
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|  *
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|  *  right_node          The value of the child of this node which is on
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|  *                      the right-hand side. As with all nodes on the
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|  *                      Merkle tree, this is a hash output.
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|  *
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|  *  r_node_idx          The index of this node in the Merkle tree. Note
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|  *                      that the root node of the Merkle tree is
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|  *                      1-indexed.
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|  *
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|  *  out                 The output node value, which is a hash output.
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|  */
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| static int create_merkle_internal_value(const mbedtls_lms_parameters_t *params,
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|                                         const unsigned char *left_node,
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|                                         const unsigned char *right_node,
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|                                         unsigned int r_node_idx,
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|                                         unsigned char *out)
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| {
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|     psa_hash_operation_t op;
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|     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
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|     size_t output_hash_len;
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|     unsigned char r_node_idx_bytes[4];
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| 
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|     op = psa_hash_operation_init();
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|     status = psa_hash_setup(&op, PSA_ALG_SHA_256);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, params->I_key_identifier,
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|                              MBEDTLS_LMOTS_I_KEY_ID_LEN);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     MBEDTLS_PUT_UINT32_BE(r_node_idx, r_node_idx_bytes, 0);
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|     status = psa_hash_update(&op, r_node_idx_bytes, 4);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, D_INTR_CONSTANT_BYTES, D_CONST_LEN);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, left_node,
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|                              MBEDTLS_LMS_M_NODE_BYTES(params->type));
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_update(&op, right_node,
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|                              MBEDTLS_LMS_M_NODE_BYTES(params->type));
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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|     status = psa_hash_finish(&op, out, MBEDTLS_LMS_M_NODE_BYTES(params->type),
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|                              &output_hash_len);
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|     if (status != PSA_SUCCESS) {
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|         goto exit;
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|     }
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| 
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| exit:
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|     psa_hash_abort(&op);
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| 
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|     return PSA_TO_MBEDTLS_ERR(status);
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| }
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| 
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| void mbedtls_lms_public_init(mbedtls_lms_public_t *ctx)
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| {
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|     memset(ctx, 0, sizeof(*ctx));
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| }
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| 
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| void mbedtls_lms_public_free(mbedtls_lms_public_t *ctx)
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| {
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|     if (ctx == NULL) {
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|         return;
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|     }
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| 
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|     mbedtls_platform_zeroize(ctx, sizeof(*ctx));
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| }
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| 
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| int mbedtls_lms_import_public_key(mbedtls_lms_public_t *ctx,
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|                                   const unsigned char *key, size_t key_size)
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| {
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|     mbedtls_lms_algorithm_type_t type;
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|     mbedtls_lmots_algorithm_type_t otstype;
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| 
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|     type = (mbedtls_lms_algorithm_type_t) MBEDTLS_GET_UINT32_BE(key, PUBLIC_KEY_TYPE_OFFSET);
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|     if (type != MBEDTLS_LMS_SHA256_M32_H10) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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|     ctx->params.type = type;
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| 
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|     if (key_size != MBEDTLS_LMS_PUBLIC_KEY_LEN(ctx->params.type)) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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| 
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|     otstype = (mbedtls_lmots_algorithm_type_t)
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|               MBEDTLS_GET_UINT32_BE(key, PUBLIC_KEY_OTSTYPE_OFFSET);
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|     if (otstype != MBEDTLS_LMOTS_SHA256_N32_W8) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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|     ctx->params.otstype = otstype;
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| 
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|     memcpy(ctx->params.I_key_identifier,
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|            key + PUBLIC_KEY_I_KEY_ID_OFFSET,
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|            MBEDTLS_LMOTS_I_KEY_ID_LEN);
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|     memcpy(ctx->T_1_pub_key, key + PUBLIC_KEY_ROOT_NODE_OFFSET,
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|            MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type));
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| 
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|     ctx->have_public_key = 1;
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| 
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|     return 0;
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| }
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| 
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| int mbedtls_lms_export_public_key(const mbedtls_lms_public_t *ctx,
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|                                   unsigned char *key,
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|                                   size_t key_size, size_t *key_len)
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| {
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|     if (key_size < MBEDTLS_LMS_PUBLIC_KEY_LEN(ctx->params.type)) {
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|         return MBEDTLS_ERR_LMS_BUFFER_TOO_SMALL;
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|     }
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| 
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|     if (!ctx->have_public_key) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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| 
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|     MBEDTLS_PUT_UINT32_BE(ctx->params.type, key, PUBLIC_KEY_TYPE_OFFSET);
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|     MBEDTLS_PUT_UINT32_BE(ctx->params.otstype, key, PUBLIC_KEY_OTSTYPE_OFFSET);
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|     memcpy(key + PUBLIC_KEY_I_KEY_ID_OFFSET,
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|            ctx->params.I_key_identifier,
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|            MBEDTLS_LMOTS_I_KEY_ID_LEN);
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|     memcpy(key +PUBLIC_KEY_ROOT_NODE_OFFSET,
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|            ctx->T_1_pub_key,
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|            MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type));
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| 
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|     if (key_len != NULL) {
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|         *key_len = MBEDTLS_LMS_PUBLIC_KEY_LEN(ctx->params.type);
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|     }
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| 
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|     return 0;
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| }
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| 
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| int mbedtls_lms_verify(const mbedtls_lms_public_t *ctx,
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|                        const unsigned char *msg, size_t msg_size,
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|                        const unsigned char *sig, size_t sig_size)
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| {
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|     unsigned int q_leaf_identifier;
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|     unsigned char Kc_candidate_ots_pub_key[MBEDTLS_LMOTS_N_HASH_LEN_MAX];
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|     unsigned char Tc_candidate_root_node[MBEDTLS_LMS_M_NODE_BYTES_MAX];
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|     unsigned int height;
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|     unsigned int curr_node_id;
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|     unsigned int parent_node_id;
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|     const unsigned char *left_node;
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|     const unsigned char *right_node;
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|     mbedtls_lmots_parameters_t ots_params;
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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| 
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|     if (!ctx->have_public_key) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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| 
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|     if (ctx->params.type
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|         != MBEDTLS_LMS_SHA256_M32_H10) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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| 
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|     if (ctx->params.otstype
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|         != MBEDTLS_LMOTS_SHA256_N32_W8) {
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|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
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|     }
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| 
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|     if (sig_size != MBEDTLS_LMS_SIG_LEN(ctx->params.type, ctx->params.otstype)) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
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|     }
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| 
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|     if (sig_size < SIG_OTS_SIG_OFFSET + MBEDTLS_LMOTS_TYPE_LEN) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
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|     }
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| 
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|     if (MBEDTLS_GET_UINT32_BE(sig, SIG_OTS_SIG_OFFSET + MBEDTLS_LMOTS_SIG_TYPE_OFFSET)
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|         != MBEDTLS_LMOTS_SHA256_N32_W8) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
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|     }
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| 
 | |
|     if (sig_size < SIG_TYPE_OFFSET(ctx->params.otstype) + MBEDTLS_LMS_TYPE_LEN) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
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|     }
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| 
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|     if (MBEDTLS_GET_UINT32_BE(sig, SIG_TYPE_OFFSET(ctx->params.otstype))
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|         != MBEDTLS_LMS_SHA256_M32_H10) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
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|     }
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| 
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| 
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|     q_leaf_identifier = MBEDTLS_GET_UINT32_BE(sig, SIG_Q_LEAF_ID_OFFSET);
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| 
 | |
|     if (q_leaf_identifier >= MERKLE_TREE_LEAF_NODE_AM(ctx->params.type)) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
 | |
|     }
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| 
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|     memcpy(ots_params.I_key_identifier,
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|            ctx->params.I_key_identifier,
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|            MBEDTLS_LMOTS_I_KEY_ID_LEN);
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|     MBEDTLS_PUT_UINT32_BE(q_leaf_identifier, ots_params.q_leaf_identifier, 0);
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|     ots_params.type = ctx->params.otstype;
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| 
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|     ret = mbedtls_lmots_calculate_public_key_candidate(&ots_params,
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|                                                        msg,
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|                                                        msg_size,
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|                                                        sig + SIG_OTS_SIG_OFFSET,
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|                                                        MBEDTLS_LMOTS_SIG_LEN(ctx->params.otstype),
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|                                                        Kc_candidate_ots_pub_key,
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|                                                        sizeof(Kc_candidate_ots_pub_key),
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|                                                        NULL);
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|     if (ret != 0) {
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|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
 | |
|     }
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| 
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|     create_merkle_leaf_value(
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|         &ctx->params,
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|         Kc_candidate_ots_pub_key,
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|         MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type) + q_leaf_identifier,
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|         Tc_candidate_root_node);
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| 
 | |
|     curr_node_id = MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type) +
 | |
|                    q_leaf_identifier;
 | |
| 
 | |
|     for (height = 0; height < MBEDTLS_LMS_H_TREE_HEIGHT(ctx->params.type);
 | |
|          height++) {
 | |
|         parent_node_id = curr_node_id / 2;
 | |
| 
 | |
|         /* Left/right node ordering matters for the hash */
 | |
|         if (curr_node_id & 1) {
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|             left_node = sig + SIG_PATH_OFFSET(ctx->params.otstype) +
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|                         height * MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type);
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|             right_node = Tc_candidate_root_node;
 | |
|         } else {
 | |
|             left_node = Tc_candidate_root_node;
 | |
|             right_node = sig + SIG_PATH_OFFSET(ctx->params.otstype) +
 | |
|                          height * MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type);
 | |
|         }
 | |
| 
 | |
|         create_merkle_internal_value(&ctx->params, left_node, right_node,
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|                                      parent_node_id, Tc_candidate_root_node);
 | |
| 
 | |
|         curr_node_id /= 2;
 | |
|     }
 | |
| 
 | |
|     if (memcmp(Tc_candidate_root_node, ctx->T_1_pub_key,
 | |
|                MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type))) {
 | |
|         return MBEDTLS_ERR_LMS_VERIFY_FAILED;
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| #if defined(MBEDTLS_LMS_PRIVATE)
 | |
| 
 | |
| /* Calculate a full Merkle tree based on a private key. This function
 | |
|  * implements RFC8554 section 5.3, and is used to generate a public key (as the
 | |
|  * public key is the root node of the Merkle tree).
 | |
|  *
 | |
|  *  ctx                 The LMS private context, containing a parameter
 | |
|  *                      set and private key material consisting of both
 | |
|  *                      public and private OTS.
 | |
|  *
 | |
|  *  tree                The output tree, which is 2^(H + 1) hash outputs.
 | |
|  *                      In the case of H=10 we have 2048 tree nodes (of
 | |
|  *                      which 1024 of them are leaf nodes). Note that
 | |
|  *                      because the Merkle tree root is 1-indexed, the 0
 | |
|  *                      index tree node is never used.
 | |
|  */
 | |
| static int calculate_merkle_tree(const mbedtls_lms_private_t *ctx,
 | |
|                                  unsigned char *tree)
 | |
| {
 | |
|     unsigned int priv_key_idx;
 | |
|     unsigned int r_node_idx;
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
| 
 | |
|     /* First create the leaf nodes, in ascending order */
 | |
|     for (priv_key_idx = 0;
 | |
|          priv_key_idx < MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type);
 | |
|          priv_key_idx++) {
 | |
|         r_node_idx = MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type) + priv_key_idx;
 | |
| 
 | |
|         ret = create_merkle_leaf_value(&ctx->params,
 | |
|                                        ctx->ots_public_keys[priv_key_idx].public_key,
 | |
|                                        r_node_idx,
 | |
|                                        &tree[r_node_idx * MBEDTLS_LMS_M_NODE_BYTES(
 | |
|                                                  ctx->params.type)]);
 | |
|         if (ret != 0) {
 | |
|             return ret;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /* Then the internal nodes, in reverse order so that we can guarantee the
 | |
|      * parent has been created */
 | |
|     for (r_node_idx = MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type) - 1;
 | |
|          r_node_idx > 0;
 | |
|          r_node_idx--) {
 | |
|         ret = create_merkle_internal_value(&ctx->params,
 | |
|                                            &tree[(r_node_idx * 2) *
 | |
|                                                  MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type)],
 | |
|                                            &tree[(r_node_idx * 2 + 1) *
 | |
|                                                  MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type)],
 | |
|                                            r_node_idx,
 | |
|                                            &tree[r_node_idx *
 | |
|                                                  MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type)]);
 | |
|         if (ret != 0) {
 | |
|             return ret;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| /* Calculate a path from a leaf node of the Merkle tree to the root of the tree,
 | |
|  * and return the full path. This function implements RFC8554 section 5.4.1, as
 | |
|  * the Merkle path is the main component of an LMS signature.
 | |
|  *
 | |
|  *  ctx                 The LMS private context, containing a parameter
 | |
|  *                      set and private key material consisting of both
 | |
|  *                      public and private OTS.
 | |
|  *
 | |
|  *  leaf_node_id        Which leaf node to calculate the path from.
 | |
|  *
 | |
|  *  path                The output path, which is H hash outputs.
 | |
|  */
 | |
| static int get_merkle_path(mbedtls_lms_private_t *ctx,
 | |
|                            unsigned int leaf_node_id,
 | |
|                            unsigned char *path)
 | |
| {
 | |
|     const size_t node_bytes = MBEDTLS_LMS_M_NODE_BYTES(ctx->params.type);
 | |
|     unsigned int curr_node_id = leaf_node_id;
 | |
|     unsigned int adjacent_node_id;
 | |
|     unsigned char *tree = NULL;
 | |
|     unsigned int height;
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
| 
 | |
|     tree = mbedtls_calloc((size_t) MERKLE_TREE_NODE_AM(ctx->params.type),
 | |
|                           node_bytes);
 | |
|     if (tree == NULL) {
 | |
|         return MBEDTLS_ERR_LMS_ALLOC_FAILED;
 | |
|     }
 | |
| 
 | |
|     ret = calculate_merkle_tree(ctx, tree);
 | |
|     if (ret != 0) {
 | |
|         goto exit;
 | |
|     }
 | |
| 
 | |
|     for (height = 0; height < MBEDTLS_LMS_H_TREE_HEIGHT(ctx->params.type);
 | |
|          height++) {
 | |
|         adjacent_node_id = curr_node_id ^ 1;
 | |
| 
 | |
|         memcpy(&path[height * node_bytes],
 | |
|                &tree[adjacent_node_id * node_bytes], node_bytes);
 | |
| 
 | |
|         curr_node_id >>= 1;
 | |
|     }
 | |
| 
 | |
|     ret = 0;
 | |
| 
 | |
| exit:
 | |
|     mbedtls_zeroize_and_free(tree, node_bytes *
 | |
|                              (size_t) MERKLE_TREE_NODE_AM(ctx->params.type));
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| void mbedtls_lms_private_init(mbedtls_lms_private_t *ctx)
 | |
| {
 | |
|     memset(ctx, 0, sizeof(*ctx));
 | |
| }
 | |
| 
 | |
| void mbedtls_lms_private_free(mbedtls_lms_private_t *ctx)
 | |
| {
 | |
|     if (ctx == NULL) {
 | |
|         return;
 | |
|     }
 | |
| 
 | |
|     unsigned int idx;
 | |
| 
 | |
|     if (ctx->have_private_key) {
 | |
|         if (ctx->ots_private_keys != NULL) {
 | |
|             for (idx = 0; idx < MERKLE_TREE_LEAF_NODE_AM(ctx->params.type); idx++) {
 | |
|                 mbedtls_lmots_private_free(&ctx->ots_private_keys[idx]);
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         if (ctx->ots_public_keys != NULL) {
 | |
|             for (idx = 0; idx < MERKLE_TREE_LEAF_NODE_AM(ctx->params.type); idx++) {
 | |
|                 mbedtls_lmots_public_free(&ctx->ots_public_keys[idx]);
 | |
|             }
 | |
|         }
 | |
| 
 | |
|         mbedtls_free(ctx->ots_private_keys);
 | |
|         mbedtls_free(ctx->ots_public_keys);
 | |
|     }
 | |
| 
 | |
|     mbedtls_platform_zeroize(ctx, sizeof(*ctx));
 | |
| }
 | |
| 
 | |
| 
 | |
| int mbedtls_lms_generate_private_key(mbedtls_lms_private_t *ctx,
 | |
|                                      mbedtls_lms_algorithm_type_t type,
 | |
|                                      mbedtls_lmots_algorithm_type_t otstype,
 | |
|                                      int (*f_rng)(void *, unsigned char *, size_t),
 | |
|                                      void *p_rng, const unsigned char *seed,
 | |
|                                      size_t seed_size)
 | |
| {
 | |
|     unsigned int idx = 0;
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
| 
 | |
|     if (type != MBEDTLS_LMS_SHA256_M32_H10) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (otstype != MBEDTLS_LMOTS_SHA256_N32_W8) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (ctx->have_private_key) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     ctx->params.type = type;
 | |
|     ctx->params.otstype = otstype;
 | |
|     ctx->have_private_key = 1;
 | |
| 
 | |
|     ret = f_rng(p_rng,
 | |
|                 ctx->params.I_key_identifier,
 | |
|                 MBEDTLS_LMOTS_I_KEY_ID_LEN);
 | |
|     if (ret != 0) {
 | |
|         goto exit;
 | |
|     }
 | |
| 
 | |
|     /* Requires a cast to size_t to avoid an implicit cast warning on certain
 | |
|      * platforms (particularly Windows) */
 | |
|     ctx->ots_private_keys = mbedtls_calloc((size_t) MERKLE_TREE_LEAF_NODE_AM(ctx->params.type),
 | |
|                                            sizeof(*ctx->ots_private_keys));
 | |
|     if (ctx->ots_private_keys == NULL) {
 | |
|         ret = MBEDTLS_ERR_LMS_ALLOC_FAILED;
 | |
|         goto exit;
 | |
|     }
 | |
| 
 | |
|     /* Requires a cast to size_t to avoid an implicit cast warning on certain
 | |
|      * platforms (particularly Windows) */
 | |
|     ctx->ots_public_keys = mbedtls_calloc((size_t) MERKLE_TREE_LEAF_NODE_AM(ctx->params.type),
 | |
|                                           sizeof(*ctx->ots_public_keys));
 | |
|     if (ctx->ots_public_keys == NULL) {
 | |
|         ret = MBEDTLS_ERR_LMS_ALLOC_FAILED;
 | |
|         goto exit;
 | |
|     }
 | |
| 
 | |
|     for (idx = 0; idx < MERKLE_TREE_LEAF_NODE_AM(ctx->params.type); idx++) {
 | |
|         mbedtls_lmots_private_init(&ctx->ots_private_keys[idx]);
 | |
|         mbedtls_lmots_public_init(&ctx->ots_public_keys[idx]);
 | |
|     }
 | |
| 
 | |
| 
 | |
|     for (idx = 0; idx < MERKLE_TREE_LEAF_NODE_AM(ctx->params.type); idx++) {
 | |
|         ret = mbedtls_lmots_generate_private_key(&ctx->ots_private_keys[idx],
 | |
|                                                  otstype,
 | |
|                                                  ctx->params.I_key_identifier,
 | |
|                                                  idx, seed, seed_size);
 | |
|         if (ret != 0) {
 | |
|             goto exit;
 | |
|         }
 | |
| 
 | |
|         ret = mbedtls_lmots_calculate_public_key(&ctx->ots_public_keys[idx],
 | |
|                                                  &ctx->ots_private_keys[idx]);
 | |
|         if (ret != 0) {
 | |
|             goto exit;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     ctx->q_next_usable_key = 0;
 | |
| 
 | |
| exit:
 | |
|     if (ret != 0) {
 | |
|         mbedtls_lms_private_free(ctx);
 | |
|     }
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| int mbedtls_lms_calculate_public_key(mbedtls_lms_public_t *ctx,
 | |
|                                      const mbedtls_lms_private_t *priv_ctx)
 | |
| {
 | |
|     const size_t node_bytes = MBEDTLS_LMS_M_NODE_BYTES(priv_ctx->params.type);
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     unsigned char *tree = NULL;
 | |
| 
 | |
|     if (!priv_ctx->have_private_key) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (priv_ctx->params.type
 | |
|         != MBEDTLS_LMS_SHA256_M32_H10) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (priv_ctx->params.otstype
 | |
|         != MBEDTLS_LMOTS_SHA256_N32_W8) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     tree = mbedtls_calloc((size_t) MERKLE_TREE_NODE_AM(priv_ctx->params.type),
 | |
|                           node_bytes);
 | |
|     if (tree == NULL) {
 | |
|         return MBEDTLS_ERR_LMS_ALLOC_FAILED;
 | |
|     }
 | |
| 
 | |
|     memcpy(&ctx->params, &priv_ctx->params,
 | |
|            sizeof(mbedtls_lmots_parameters_t));
 | |
| 
 | |
|     ret = calculate_merkle_tree(priv_ctx, tree);
 | |
|     if (ret != 0) {
 | |
|         goto exit;
 | |
|     }
 | |
| 
 | |
|     /* Root node is always at position 1, due to 1-based indexing */
 | |
|     memcpy(ctx->T_1_pub_key, &tree[node_bytes], node_bytes);
 | |
| 
 | |
|     ctx->have_public_key = 1;
 | |
| 
 | |
|     ret = 0;
 | |
| 
 | |
| exit:
 | |
|     mbedtls_zeroize_and_free(tree, node_bytes *
 | |
|                              (size_t) MERKLE_TREE_NODE_AM(priv_ctx->params.type));
 | |
| 
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| 
 | |
| int mbedtls_lms_sign(mbedtls_lms_private_t *ctx,
 | |
|                      int (*f_rng)(void *, unsigned char *, size_t),
 | |
|                      void *p_rng, const unsigned char *msg,
 | |
|                      unsigned int msg_size, unsigned char *sig, size_t sig_size,
 | |
|                      size_t *sig_len)
 | |
| {
 | |
|     uint32_t q_leaf_identifier;
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
| 
 | |
|     if (!ctx->have_private_key) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (sig_size < MBEDTLS_LMS_SIG_LEN(ctx->params.type, ctx->params.otstype)) {
 | |
|         return MBEDTLS_ERR_LMS_BUFFER_TOO_SMALL;
 | |
|     }
 | |
| 
 | |
|     if (ctx->params.type != MBEDTLS_LMS_SHA256_M32_H10) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (ctx->params.otstype
 | |
|         != MBEDTLS_LMOTS_SHA256_N32_W8) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     if (ctx->q_next_usable_key >= MERKLE_TREE_LEAF_NODE_AM(ctx->params.type)) {
 | |
|         return MBEDTLS_ERR_LMS_OUT_OF_PRIVATE_KEYS;
 | |
|     }
 | |
| 
 | |
| 
 | |
|     q_leaf_identifier = ctx->q_next_usable_key;
 | |
|     /* This new value must _always_ be written back to the disk before the
 | |
|      * signature is returned.
 | |
|      */
 | |
|     ctx->q_next_usable_key += 1;
 | |
| 
 | |
|     if (MBEDTLS_LMS_SIG_LEN(ctx->params.type, ctx->params.otstype)
 | |
|         < SIG_OTS_SIG_OFFSET) {
 | |
|         return MBEDTLS_ERR_LMS_BAD_INPUT_DATA;
 | |
|     }
 | |
| 
 | |
|     ret = mbedtls_lmots_sign(&ctx->ots_private_keys[q_leaf_identifier],
 | |
|                              f_rng,
 | |
|                              p_rng,
 | |
|                              msg,
 | |
|                              msg_size,
 | |
|                              sig + SIG_OTS_SIG_OFFSET,
 | |
|                              MBEDTLS_LMS_SIG_LEN(ctx->params.type,
 | |
|                                                  ctx->params.otstype) - SIG_OTS_SIG_OFFSET,
 | |
|                              NULL);
 | |
|     if (ret != 0) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     MBEDTLS_PUT_UINT32_BE(ctx->params.type, sig, SIG_TYPE_OFFSET(ctx->params.otstype));
 | |
|     MBEDTLS_PUT_UINT32_BE(q_leaf_identifier, sig, SIG_Q_LEAF_ID_OFFSET);
 | |
| 
 | |
|     ret = get_merkle_path(ctx,
 | |
|                           MERKLE_TREE_INTERNAL_NODE_AM(ctx->params.type) + q_leaf_identifier,
 | |
|                           sig + SIG_PATH_OFFSET(ctx->params.otstype));
 | |
|     if (ret != 0) {
 | |
|         return ret;
 | |
|     }
 | |
| 
 | |
|     if (sig_len != NULL) {
 | |
|         *sig_len = MBEDTLS_LMS_SIG_LEN(ctx->params.type, ctx->params.otstype);
 | |
|     }
 | |
| 
 | |
| 
 | |
|     return 0;
 | |
| }
 | |
| 
 | |
| #endif /* defined(MBEDTLS_LMS_PRIVATE) */
 | |
| #endif /* defined(MBEDTLS_LMS_C) */
 |