738 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			738 lines
		
	
	
		
			27 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
|  | /*
 | ||
|  |  *  PSA RSA layer on top of Mbed TLS crypto | ||
|  |  */ | ||
|  | /*
 | ||
|  |  *  Copyright The Mbed TLS Contributors | ||
|  |  *  SPDX-License-Identifier: Apache-2.0 | ||
|  |  * | ||
|  |  *  Licensed under the Apache License, Version 2.0 (the "License"); you may | ||
|  |  *  not use this file except in compliance with the License. | ||
|  |  *  You may obtain a copy of the License at | ||
|  |  * | ||
|  |  *  http://www.apache.org/licenses/LICENSE-2.0
 | ||
|  |  * | ||
|  |  *  Unless required by applicable law or agreed to in writing, software | ||
|  |  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT | ||
|  |  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
|  |  *  See the License for the specific language governing permissions and | ||
|  |  *  limitations under the License. | ||
|  |  */ | ||
|  | 
 | ||
|  | #include "common.h"
 | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_CRYPTO_C)
 | ||
|  | 
 | ||
|  | #include <psa/crypto.h>
 | ||
|  | #include "psa/crypto_values.h"
 | ||
|  | #include "psa_crypto_core.h"
 | ||
|  | #include "psa_crypto_random_impl.h"
 | ||
|  | #include "psa_crypto_rsa.h"
 | ||
|  | #include "psa_crypto_hash.h"
 | ||
|  | #include "md_psa.h"
 | ||
|  | 
 | ||
|  | #include <stdlib.h>
 | ||
|  | #include <string.h>
 | ||
|  | #include "mbedtls/platform.h"
 | ||
|  | 
 | ||
|  | #include <mbedtls/rsa.h>
 | ||
|  | #include <mbedtls/error.h>
 | ||
|  | #include <mbedtls/pk.h>
 | ||
|  | #include "pk_wrap.h"
 | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) || \
 | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) | ||
|  | 
 | ||
|  | /* Mbed TLS doesn't support non-byte-aligned key sizes (i.e. key sizes
 | ||
|  |  * that are not a multiple of 8) well. For example, there is only | ||
|  |  * mbedtls_rsa_get_len(), which returns a number of bytes, and no | ||
|  |  * way to return the exact bit size of a key. | ||
|  |  * To keep things simple, reject non-byte-aligned key sizes. */ | ||
|  | static psa_status_t psa_check_rsa_key_byte_aligned( | ||
|  |     const mbedtls_rsa_context *rsa) | ||
|  | { | ||
|  |     mbedtls_mpi n; | ||
|  |     psa_status_t status; | ||
|  |     mbedtls_mpi_init(&n); | ||
|  |     status = mbedtls_to_psa_error( | ||
|  |         mbedtls_rsa_export(rsa, &n, NULL, NULL, NULL, NULL)); | ||
|  |     if (status == PSA_SUCCESS) { | ||
|  |         if (mbedtls_mpi_bitlen(&n) % 8 != 0) { | ||
|  |             status = PSA_ERROR_NOT_SUPPORTED; | ||
|  |         } | ||
|  |     } | ||
|  |     mbedtls_mpi_free(&n); | ||
|  |     return status; | ||
|  | } | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_rsa_load_representation( | ||
|  |     psa_key_type_t type, const uint8_t *data, size_t data_length, | ||
|  |     mbedtls_rsa_context **p_rsa) | ||
|  | { | ||
|  |     psa_status_t status; | ||
|  |     mbedtls_pk_context ctx; | ||
|  |     size_t bits; | ||
|  |     mbedtls_pk_init(&ctx); | ||
|  | 
 | ||
|  |     /* Parse the data. */ | ||
|  |     if (PSA_KEY_TYPE_IS_KEY_PAIR(type)) { | ||
|  |         status = mbedtls_to_psa_error( | ||
|  |             mbedtls_pk_parse_key(&ctx, data, data_length, NULL, 0, | ||
|  |                                  mbedtls_psa_get_random, MBEDTLS_PSA_RANDOM_STATE)); | ||
|  |     } else { | ||
|  |         status = mbedtls_to_psa_error( | ||
|  |             mbedtls_pk_parse_public_key(&ctx, data, data_length)); | ||
|  |     } | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* We have something that the pkparse module recognizes. If it is a
 | ||
|  |      * valid RSA key, store it. */ | ||
|  |     if (mbedtls_pk_get_type(&ctx) != MBEDTLS_PK_RSA) { | ||
|  |         status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* The size of an RSA key doesn't have to be a multiple of 8. Mbed TLS
 | ||
|  |      * supports non-byte-aligned key sizes, but not well. For example, | ||
|  |      * mbedtls_rsa_get_len() returns the key size in bytes, not in bits. */ | ||
|  |     bits = PSA_BYTES_TO_BITS(mbedtls_rsa_get_len(mbedtls_pk_rsa(ctx))); | ||
|  |     if (bits > PSA_VENDOR_RSA_MAX_KEY_BITS) { | ||
|  |         status = PSA_ERROR_NOT_SUPPORTED; | ||
|  |         goto exit; | ||
|  |     } | ||
|  |     status = psa_check_rsa_key_byte_aligned(mbedtls_pk_rsa(ctx)); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* Copy out the pointer to the RSA context, and reset the PK context
 | ||
|  |      * such that pk_free doesn't free the RSA context we just grabbed. */ | ||
|  |     *p_rsa = mbedtls_pk_rsa(ctx); | ||
|  |     ctx.pk_info = NULL; | ||
|  | 
 | ||
|  | exit: | ||
|  |     mbedtls_pk_free(&ctx); | ||
|  |     return status; | ||
|  | } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */ | ||
|  | 
 | ||
|  | #if (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) && \
 | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) || \ | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) | ||
|  | psa_status_t mbedtls_psa_rsa_import_key( | ||
|  |     const psa_key_attributes_t *attributes, | ||
|  |     const uint8_t *data, size_t data_length, | ||
|  |     uint8_t *key_buffer, size_t key_buffer_size, | ||
|  |     size_t *key_buffer_length, size_t *bits) | ||
|  | { | ||
|  |     psa_status_t status; | ||
|  |     mbedtls_rsa_context *rsa = NULL; | ||
|  | 
 | ||
|  |     /* Parse input */ | ||
|  |     status = mbedtls_psa_rsa_load_representation(attributes->core.type, | ||
|  |                                                  data, | ||
|  |                                                  data_length, | ||
|  |                                                  &rsa); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     *bits = (psa_key_bits_t) PSA_BYTES_TO_BITS(mbedtls_rsa_get_len(rsa)); | ||
|  | 
 | ||
|  |     /* Re-export the data to PSA export format, such that we can store export
 | ||
|  |      * representation in the key slot. Export representation in case of RSA is | ||
|  |      * the smallest representation that's allowed as input, so a straight-up | ||
|  |      * allocation of the same size as the input buffer will be large enough. */ | ||
|  |     status = mbedtls_psa_rsa_export_key(attributes->core.type, | ||
|  |                                         rsa, | ||
|  |                                         key_buffer, | ||
|  |                                         key_buffer_size, | ||
|  |                                         key_buffer_length); | ||
|  | exit: | ||
|  |     /* Always free the RSA object */ | ||
|  |     mbedtls_rsa_free(rsa); | ||
|  |     mbedtls_free(rsa); | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | #endif /* (defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_IMPORT) &&
 | ||
|  |         *  defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT)) || | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */ | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) || \
 | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) | ||
|  | psa_status_t mbedtls_psa_rsa_export_key(psa_key_type_t type, | ||
|  |                                         mbedtls_rsa_context *rsa, | ||
|  |                                         uint8_t *data, | ||
|  |                                         size_t data_size, | ||
|  |                                         size_t *data_length) | ||
|  | { | ||
|  |     int ret; | ||
|  |     mbedtls_pk_context pk; | ||
|  |     uint8_t *pos = data + data_size; | ||
|  | 
 | ||
|  |     mbedtls_pk_init(&pk); | ||
|  |     pk.pk_info = &mbedtls_rsa_info; | ||
|  |     pk.pk_ctx = rsa; | ||
|  | 
 | ||
|  |     /* PSA Crypto API defines the format of an RSA key as a DER-encoded
 | ||
|  |      * representation of the non-encrypted PKCS#1 RSAPrivateKey for a | ||
|  |      * private key and of the RFC3279 RSAPublicKey for a public key. */ | ||
|  |     if (PSA_KEY_TYPE_IS_KEY_PAIR(type)) { | ||
|  |         ret = mbedtls_pk_write_key_der(&pk, data, data_size); | ||
|  |     } else { | ||
|  |         ret = mbedtls_pk_write_pubkey(&pos, data, &pk); | ||
|  |     } | ||
|  | 
 | ||
|  |     if (ret < 0) { | ||
|  |         /* Clean up in case pk_write failed halfway through. */ | ||
|  |         memset(data, 0, data_size); | ||
|  |         return mbedtls_to_psa_error(ret); | ||
|  |     } | ||
|  | 
 | ||
|  |     /* The mbedtls_pk_xxx functions write to the end of the buffer.
 | ||
|  |      * Move the data to the beginning and erase remaining data | ||
|  |      * at the original location. */ | ||
|  |     if (2 * (size_t) ret <= data_size) { | ||
|  |         memcpy(data, data + data_size - ret, ret); | ||
|  |         memset(data + data_size - ret, 0, ret); | ||
|  |     } else if ((size_t) ret < data_size) { | ||
|  |         memmove(data, data + data_size - ret, ret); | ||
|  |         memset(data + ret, 0, data_size - ret); | ||
|  |     } | ||
|  | 
 | ||
|  |     *data_length = ret; | ||
|  |     return PSA_SUCCESS; | ||
|  | } | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_rsa_export_public_key( | ||
|  |     const psa_key_attributes_t *attributes, | ||
|  |     const uint8_t *key_buffer, size_t key_buffer_size, | ||
|  |     uint8_t *data, size_t data_size, size_t *data_length) | ||
|  | { | ||
|  |     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; | ||
|  |     mbedtls_rsa_context *rsa = NULL; | ||
|  | 
 | ||
|  |     status = mbedtls_psa_rsa_load_representation( | ||
|  |         attributes->core.type, key_buffer, key_buffer_size, &rsa); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         return status; | ||
|  |     } | ||
|  | 
 | ||
|  |     status = mbedtls_psa_rsa_export_key(PSA_KEY_TYPE_RSA_PUBLIC_KEY, | ||
|  |                                         rsa, | ||
|  |                                         data, | ||
|  |                                         data_size, | ||
|  |                                         data_length); | ||
|  | 
 | ||
|  |     mbedtls_rsa_free(rsa); | ||
|  |     mbedtls_free(rsa); | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_EXPORT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_PUBLIC_KEY) */ | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_GENERATE)
 | ||
|  | static psa_status_t psa_rsa_read_exponent(const uint8_t *domain_parameters, | ||
|  |                                           size_t domain_parameters_size, | ||
|  |                                           int *exponent) | ||
|  | { | ||
|  |     size_t i; | ||
|  |     uint32_t acc = 0; | ||
|  | 
 | ||
|  |     if (domain_parameters_size == 0) { | ||
|  |         *exponent = 65537; | ||
|  |         return PSA_SUCCESS; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* Mbed TLS encodes the public exponent as an int. For simplicity, only
 | ||
|  |      * support values that fit in a 32-bit integer, which is larger than | ||
|  |      * int on just about every platform anyway. */ | ||
|  |     if (domain_parameters_size > sizeof(acc)) { | ||
|  |         return PSA_ERROR_NOT_SUPPORTED; | ||
|  |     } | ||
|  |     for (i = 0; i < domain_parameters_size; i++) { | ||
|  |         acc = (acc << 8) | domain_parameters[i]; | ||
|  |     } | ||
|  |     if (acc > INT_MAX) { | ||
|  |         return PSA_ERROR_NOT_SUPPORTED; | ||
|  |     } | ||
|  |     *exponent = acc; | ||
|  |     return PSA_SUCCESS; | ||
|  | } | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_rsa_generate_key( | ||
|  |     const psa_key_attributes_t *attributes, | ||
|  |     uint8_t *key_buffer, size_t key_buffer_size, size_t *key_buffer_length) | ||
|  | { | ||
|  |     psa_status_t status; | ||
|  |     mbedtls_rsa_context rsa; | ||
|  |     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; | ||
|  |     int exponent; | ||
|  | 
 | ||
|  |     status = psa_rsa_read_exponent(attributes->domain_parameters, | ||
|  |                                    attributes->domain_parameters_size, | ||
|  |                                    &exponent); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         return status; | ||
|  |     } | ||
|  | 
 | ||
|  |     mbedtls_rsa_init(&rsa); | ||
|  |     ret = mbedtls_rsa_gen_key(&rsa, | ||
|  |                               mbedtls_psa_get_random, | ||
|  |                               MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                               (unsigned int) attributes->core.bits, | ||
|  |                               exponent); | ||
|  |     if (ret != 0) { | ||
|  |         return mbedtls_to_psa_error(ret); | ||
|  |     } | ||
|  | 
 | ||
|  |     status = mbedtls_psa_rsa_export_key(attributes->core.type, | ||
|  |                                         &rsa, key_buffer, key_buffer_size, | ||
|  |                                         key_buffer_length); | ||
|  |     mbedtls_rsa_free(&rsa); | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_RSA_KEY_PAIR_GENERATE) */
 | ||
|  | 
 | ||
|  | /****************************************************************/ | ||
|  | /* Sign/verify hashes */ | ||
|  | /****************************************************************/ | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) || \
 | ||
|  |     defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) | ||
|  | 
 | ||
|  | /* Decode the hash algorithm from alg and store the mbedtls encoding in
 | ||
|  |  * md_alg. Verify that the hash length is acceptable. */ | ||
|  | static psa_status_t psa_rsa_decode_md_type(psa_algorithm_t alg, | ||
|  |                                            size_t hash_length, | ||
|  |                                            mbedtls_md_type_t *md_alg) | ||
|  | { | ||
|  |     psa_algorithm_t hash_alg = PSA_ALG_SIGN_GET_HASH(alg); | ||
|  |     *md_alg = mbedtls_md_type_from_psa_alg(hash_alg); | ||
|  | 
 | ||
|  |     /* The Mbed TLS RSA module uses an unsigned int for hash length
 | ||
|  |      * parameters. Validate that it fits so that we don't risk an | ||
|  |      * overflow later. */ | ||
|  |     if (hash_length > UINT_MAX) { | ||
|  |         return PSA_ERROR_INVALID_ARGUMENT; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* For signatures using a hash, the hash length must be correct. */ | ||
|  |     if (alg != PSA_ALG_RSA_PKCS1V15_SIGN_RAW) { | ||
|  |         if (*md_alg == MBEDTLS_MD_NONE) { | ||
|  |             return PSA_ERROR_NOT_SUPPORTED; | ||
|  |         } | ||
|  |         if (mbedtls_md_get_size_from_type(*md_alg) != hash_length) { | ||
|  |             return PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         } | ||
|  |     } | ||
|  | 
 | ||
|  |     return PSA_SUCCESS; | ||
|  | } | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_rsa_sign_hash( | ||
|  |     const psa_key_attributes_t *attributes, | ||
|  |     const uint8_t *key_buffer, size_t key_buffer_size, | ||
|  |     psa_algorithm_t alg, const uint8_t *hash, size_t hash_length, | ||
|  |     uint8_t *signature, size_t signature_size, size_t *signature_length) | ||
|  | { | ||
|  |     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; | ||
|  |     mbedtls_rsa_context *rsa = NULL; | ||
|  |     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; | ||
|  |     mbedtls_md_type_t md_alg; | ||
|  | 
 | ||
|  |     status = mbedtls_psa_rsa_load_representation(attributes->core.type, | ||
|  |                                                  key_buffer, | ||
|  |                                                  key_buffer_size, | ||
|  |                                                  &rsa); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         return status; | ||
|  |     } | ||
|  | 
 | ||
|  |     status = psa_rsa_decode_md_type(alg, hash_length, &md_alg); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     if (signature_size < mbedtls_rsa_get_len(rsa)) { | ||
|  |         status = PSA_ERROR_BUFFER_TOO_SMALL; | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN)
 | ||
|  |     if (PSA_ALG_IS_RSA_PKCS1V15_SIGN(alg)) { | ||
|  |         ret = mbedtls_rsa_set_padding(rsa, MBEDTLS_RSA_PKCS_V15, | ||
|  |                                       MBEDTLS_MD_NONE); | ||
|  |         if (ret == 0) { | ||
|  |             ret = mbedtls_rsa_pkcs1_sign(rsa, | ||
|  |                                          mbedtls_psa_get_random, | ||
|  |                                          MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                          md_alg, | ||
|  |                                          (unsigned int) hash_length, | ||
|  |                                          hash, | ||
|  |                                          signature); | ||
|  |         } | ||
|  |     } else | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN */
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS)
 | ||
|  |     if (PSA_ALG_IS_RSA_PSS(alg)) { | ||
|  |         ret = mbedtls_rsa_set_padding(rsa, MBEDTLS_RSA_PKCS_V21, md_alg); | ||
|  | 
 | ||
|  |         if (ret == 0) { | ||
|  |             ret = mbedtls_rsa_rsassa_pss_sign(rsa, | ||
|  |                                               mbedtls_psa_get_random, | ||
|  |                                               MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                               MBEDTLS_MD_NONE, | ||
|  |                                               (unsigned int) hash_length, | ||
|  |                                               hash, | ||
|  |                                               signature); | ||
|  |         } | ||
|  |     } else | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS */
 | ||
|  |     { | ||
|  |         status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     if (ret == 0) { | ||
|  |         *signature_length = mbedtls_rsa_get_len(rsa); | ||
|  |     } | ||
|  |     status = mbedtls_to_psa_error(ret); | ||
|  | 
 | ||
|  | exit: | ||
|  |     mbedtls_rsa_free(rsa); | ||
|  |     mbedtls_free(rsa); | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS)
 | ||
|  | static int rsa_pss_expected_salt_len(psa_algorithm_t alg, | ||
|  |                                      const mbedtls_rsa_context *rsa, | ||
|  |                                      size_t hash_length) | ||
|  | { | ||
|  |     if (PSA_ALG_IS_RSA_PSS_ANY_SALT(alg)) { | ||
|  |         return MBEDTLS_RSA_SALT_LEN_ANY; | ||
|  |     } | ||
|  |     /* Otherwise: standard salt length, i.e. largest possible salt length
 | ||
|  |      * up to the hash length. */ | ||
|  |     int klen = (int) mbedtls_rsa_get_len(rsa);   // known to fit
 | ||
|  |     int hlen = (int) hash_length; // known to fit
 | ||
|  |     int room = klen - 2 - hlen; | ||
|  |     if (room < 0) { | ||
|  |         return 0;  // there is no valid signature in this case anyway
 | ||
|  |     } else if (room > hlen) { | ||
|  |         return hlen; | ||
|  |     } else { | ||
|  |         return room; | ||
|  |     } | ||
|  | } | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS */
 | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_rsa_verify_hash( | ||
|  |     const psa_key_attributes_t *attributes, | ||
|  |     const uint8_t *key_buffer, size_t key_buffer_size, | ||
|  |     psa_algorithm_t alg, const uint8_t *hash, size_t hash_length, | ||
|  |     const uint8_t *signature, size_t signature_length) | ||
|  | { | ||
|  |     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; | ||
|  |     mbedtls_rsa_context *rsa = NULL; | ||
|  |     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED; | ||
|  |     mbedtls_md_type_t md_alg; | ||
|  | 
 | ||
|  |     status = mbedtls_psa_rsa_load_representation(attributes->core.type, | ||
|  |                                                  key_buffer, | ||
|  |                                                  key_buffer_size, | ||
|  |                                                  &rsa); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     status = psa_rsa_decode_md_type(alg, hash_length, &md_alg); | ||
|  |     if (status != PSA_SUCCESS) { | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     if (signature_length != mbedtls_rsa_get_len(rsa)) { | ||
|  |         status = PSA_ERROR_INVALID_SIGNATURE; | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN)
 | ||
|  |     if (PSA_ALG_IS_RSA_PKCS1V15_SIGN(alg)) { | ||
|  |         ret = mbedtls_rsa_set_padding(rsa, MBEDTLS_RSA_PKCS_V15, | ||
|  |                                       MBEDTLS_MD_NONE); | ||
|  |         if (ret == 0) { | ||
|  |             ret = mbedtls_rsa_pkcs1_verify(rsa, | ||
|  |                                            md_alg, | ||
|  |                                            (unsigned int) hash_length, | ||
|  |                                            hash, | ||
|  |                                            signature); | ||
|  |         } | ||
|  |     } else | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN */
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS)
 | ||
|  |     if (PSA_ALG_IS_RSA_PSS(alg)) { | ||
|  |         ret = mbedtls_rsa_set_padding(rsa, MBEDTLS_RSA_PKCS_V21, md_alg); | ||
|  |         if (ret == 0) { | ||
|  |             int slen = rsa_pss_expected_salt_len(alg, rsa, hash_length); | ||
|  |             ret = mbedtls_rsa_rsassa_pss_verify_ext(rsa, | ||
|  |                                                     md_alg, | ||
|  |                                                     (unsigned) hash_length, | ||
|  |                                                     hash, | ||
|  |                                                     md_alg, | ||
|  |                                                     slen, | ||
|  |                                                     signature); | ||
|  |         } | ||
|  |     } else | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS */
 | ||
|  |     { | ||
|  |         status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         goto exit; | ||
|  |     } | ||
|  | 
 | ||
|  |     /* Mbed TLS distinguishes "invalid padding" from "valid padding but
 | ||
|  |      * the rest of the signature is invalid". This has little use in | ||
|  |      * practice and PSA doesn't report this distinction. */ | ||
|  |     status = (ret == MBEDTLS_ERR_RSA_INVALID_PADDING) ? | ||
|  |              PSA_ERROR_INVALID_SIGNATURE : | ||
|  |              mbedtls_to_psa_error(ret); | ||
|  | 
 | ||
|  | exit: | ||
|  |     mbedtls_rsa_free(rsa); | ||
|  |     mbedtls_free(rsa); | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | 
 | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_SIGN) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PSS) */ | ||
|  | 
 | ||
|  | /****************************************************************/ | ||
|  | /* Asymmetric cryptography */ | ||
|  | /****************************************************************/ | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP)
 | ||
|  | static int psa_rsa_oaep_set_padding_mode(psa_algorithm_t alg, | ||
|  |                                          mbedtls_rsa_context *rsa) | ||
|  | { | ||
|  |     psa_algorithm_t hash_alg = PSA_ALG_RSA_OAEP_GET_HASH(alg); | ||
|  |     mbedtls_md_type_t md_alg = mbedtls_md_type_from_psa_alg(hash_alg); | ||
|  | 
 | ||
|  |     /* Just to get the error status right, as rsa_set_padding() doesn't
 | ||
|  |      * distinguish between "bad RSA algorithm" and "unknown hash". */ | ||
|  |     if (mbedtls_md_info_from_type(md_alg) == NULL) { | ||
|  |         return PSA_ERROR_NOT_SUPPORTED; | ||
|  |     } | ||
|  | 
 | ||
|  |     return mbedtls_rsa_set_padding(rsa, MBEDTLS_RSA_PKCS_V21, md_alg); | ||
|  | } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) */
 | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_asymmetric_encrypt(const psa_key_attributes_t *attributes, | ||
|  |                                             const uint8_t *key_buffer, | ||
|  |                                             size_t key_buffer_size, | ||
|  |                                             psa_algorithm_t alg, | ||
|  |                                             const uint8_t *input, | ||
|  |                                             size_t input_length, | ||
|  |                                             const uint8_t *salt, | ||
|  |                                             size_t salt_length, | ||
|  |                                             uint8_t *output, | ||
|  |                                             size_t output_size, | ||
|  |                                             size_t *output_length) | ||
|  | { | ||
|  |     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; | ||
|  |     (void) key_buffer; | ||
|  |     (void) key_buffer_size; | ||
|  |     (void) input; | ||
|  |     (void) input_length; | ||
|  |     (void) salt; | ||
|  |     (void) salt_length; | ||
|  |     (void) output; | ||
|  |     (void) output_size; | ||
|  |     (void) output_length; | ||
|  | 
 | ||
|  |     if (PSA_KEY_TYPE_IS_RSA(attributes->core.type)) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) || \
 | ||
|  |         defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) | ||
|  |         mbedtls_rsa_context *rsa = NULL; | ||
|  |         status = mbedtls_psa_rsa_load_representation(attributes->core.type, | ||
|  |                                                      key_buffer, | ||
|  |                                                      key_buffer_size, | ||
|  |                                                      &rsa); | ||
|  |         if (status != PSA_SUCCESS) { | ||
|  |             goto rsa_exit; | ||
|  |         } | ||
|  | 
 | ||
|  |         if (output_size < mbedtls_rsa_get_len(rsa)) { | ||
|  |             status = PSA_ERROR_BUFFER_TOO_SMALL; | ||
|  |             goto rsa_exit; | ||
|  |         } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) */ | ||
|  |         if (alg == PSA_ALG_RSA_PKCS1V15_CRYPT) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT)
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 mbedtls_rsa_pkcs1_encrypt(rsa, | ||
|  |                                           mbedtls_psa_get_random, | ||
|  |                                           MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                           input_length, | ||
|  |                                           input, | ||
|  |                                           output)); | ||
|  | #else
 | ||
|  |             status = PSA_ERROR_NOT_SUPPORTED; | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT */
 | ||
|  |         } else | ||
|  |         if (PSA_ALG_IS_RSA_OAEP(alg)) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP)
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 psa_rsa_oaep_set_padding_mode(alg, rsa)); | ||
|  |             if (status != PSA_SUCCESS) { | ||
|  |                 goto rsa_exit; | ||
|  |             } | ||
|  | 
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 mbedtls_rsa_rsaes_oaep_encrypt(rsa, | ||
|  |                                                mbedtls_psa_get_random, | ||
|  |                                                MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                                salt, salt_length, | ||
|  |                                                input_length, | ||
|  |                                                input, | ||
|  |                                                output)); | ||
|  | #else
 | ||
|  |             status = PSA_ERROR_NOT_SUPPORTED; | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP */
 | ||
|  |         } else { | ||
|  |             status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         } | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) || \
 | ||
|  |         defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) | ||
|  | rsa_exit: | ||
|  |         if (status == PSA_SUCCESS) { | ||
|  |             *output_length = mbedtls_rsa_get_len(rsa); | ||
|  |         } | ||
|  | 
 | ||
|  |         mbedtls_rsa_free(rsa); | ||
|  |         mbedtls_free(rsa); | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) */ | ||
|  |     } else { | ||
|  |         status = PSA_ERROR_NOT_SUPPORTED; | ||
|  |     } | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | 
 | ||
|  | psa_status_t mbedtls_psa_asymmetric_decrypt(const psa_key_attributes_t *attributes, | ||
|  |                                             const uint8_t *key_buffer, | ||
|  |                                             size_t key_buffer_size, | ||
|  |                                             psa_algorithm_t alg, | ||
|  |                                             const uint8_t *input, | ||
|  |                                             size_t input_length, | ||
|  |                                             const uint8_t *salt, | ||
|  |                                             size_t salt_length, | ||
|  |                                             uint8_t *output, | ||
|  |                                             size_t output_size, | ||
|  |                                             size_t *output_length) | ||
|  | { | ||
|  |     psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED; | ||
|  |     (void) key_buffer; | ||
|  |     (void) key_buffer_size; | ||
|  |     (void) input; | ||
|  |     (void) input_length; | ||
|  |     (void) salt; | ||
|  |     (void) salt_length; | ||
|  |     (void) output; | ||
|  |     (void) output_size; | ||
|  |     (void) output_length; | ||
|  | 
 | ||
|  |     *output_length = 0; | ||
|  | 
 | ||
|  |     if (attributes->core.type == PSA_KEY_TYPE_RSA_KEY_PAIR) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) || \
 | ||
|  |         defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) | ||
|  |         mbedtls_rsa_context *rsa = NULL; | ||
|  |         status = mbedtls_psa_rsa_load_representation(attributes->core.type, | ||
|  |                                                      key_buffer, | ||
|  |                                                      key_buffer_size, | ||
|  |                                                      &rsa); | ||
|  |         if (status != PSA_SUCCESS) { | ||
|  |             goto rsa_exit; | ||
|  |         } | ||
|  | 
 | ||
|  |         if (input_length != mbedtls_rsa_get_len(rsa)) { | ||
|  |             status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |             goto rsa_exit; | ||
|  |         } | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) */ | ||
|  | 
 | ||
|  |         if (alg == PSA_ALG_RSA_PKCS1V15_CRYPT) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT)
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 mbedtls_rsa_pkcs1_decrypt(rsa, | ||
|  |                                           mbedtls_psa_get_random, | ||
|  |                                           MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                           output_length, | ||
|  |                                           input, | ||
|  |                                           output, | ||
|  |                                           output_size)); | ||
|  | #else
 | ||
|  |             status = PSA_ERROR_NOT_SUPPORTED; | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT */
 | ||
|  |         } else | ||
|  |         if (PSA_ALG_IS_RSA_OAEP(alg)) { | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP)
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 psa_rsa_oaep_set_padding_mode(alg, rsa)); | ||
|  |             if (status != PSA_SUCCESS) { | ||
|  |                 goto rsa_exit; | ||
|  |             } | ||
|  | 
 | ||
|  |             status = mbedtls_to_psa_error( | ||
|  |                 mbedtls_rsa_rsaes_oaep_decrypt(rsa, | ||
|  |                                                mbedtls_psa_get_random, | ||
|  |                                                MBEDTLS_PSA_RANDOM_STATE, | ||
|  |                                                salt, salt_length, | ||
|  |                                                output_length, | ||
|  |                                                input, | ||
|  |                                                output, | ||
|  |                                                output_size)); | ||
|  | #else
 | ||
|  |             status = PSA_ERROR_NOT_SUPPORTED; | ||
|  | #endif /* MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP */
 | ||
|  |         } else { | ||
|  |             status = PSA_ERROR_INVALID_ARGUMENT; | ||
|  |         } | ||
|  | 
 | ||
|  | #if defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) || \
 | ||
|  |         defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) | ||
|  | rsa_exit: | ||
|  |         mbedtls_rsa_free(rsa); | ||
|  |         mbedtls_free(rsa); | ||
|  | #endif /* defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_PKCS1V15_CRYPT) ||
 | ||
|  |         * defined(MBEDTLS_PSA_BUILTIN_ALG_RSA_OAEP) */ | ||
|  |     } else { | ||
|  |         status = PSA_ERROR_NOT_SUPPORTED; | ||
|  |     } | ||
|  | 
 | ||
|  |     return status; | ||
|  | } | ||
|  | 
 | ||
|  | #endif /* MBEDTLS_PSA_CRYPTO_C */
 |