228abc5773
Define constants for ECC curve families and DH group families. These constants have 0x0000 in the lower 16 bits of the key type. Support these constants in the implementation and in the PSA metadata tests. Switch the slot management and secure element driver HAL tests to the new curve encodings. This requires SE driver code to become slightly more clever when figuring out the bit-size of an imported EC key since it now needs to take the data size into account. Switch some documentation to the new encodings. Remove the macro PSA_ECC_CURVE_BITS which can no longer be implemented.
662 lines
28 KiB
C
662 lines
28 KiB
C
/**
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* \file psa/crypto_sizes.h
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*
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* \brief PSA cryptography module: Mbed TLS buffer size macros
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*
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* \note This file may not be included directly. Applications must
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* include psa/crypto.h.
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*
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* This file contains the definitions of macros that are useful to
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* compute buffer sizes. The signatures and semantics of these macros
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* are standardized, but the definitions are not, because they depend on
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* the available algorithms and, in some cases, on permitted tolerances
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* on buffer sizes.
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*
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* In implementations with isolation between the application and the
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* cryptography module, implementers should take care to ensure that
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* the definitions that are exposed to applications match what the
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* module implements.
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*
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* Macros that compute sizes whose values do not depend on the
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* implementation are in crypto.h.
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*/
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/*
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* Copyright (C) 2018, ARM Limited, All Rights Reserved
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* SPDX-License-Identifier: Apache-2.0
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*
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* Licensed under the Apache License, Version 2.0 (the "License"); you may
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* not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*
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* This file is part of mbed TLS (https://tls.mbed.org)
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*/
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#ifndef PSA_CRYPTO_SIZES_H
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#define PSA_CRYPTO_SIZES_H
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/* Include the Mbed TLS configuration file, the way Mbed TLS does it
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* in each of its header files. */
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#if !defined(MBEDTLS_CONFIG_FILE)
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#include "mbedtls/config.h"
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#else
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#include MBEDTLS_CONFIG_FILE
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#endif
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#define PSA_BITS_TO_BYTES(bits) (((bits) + 7) / 8)
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#define PSA_BYTES_TO_BITS(bytes) ((bytes) * 8)
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#define PSA_ROUND_UP_TO_MULTIPLE(block_size, length) \
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(((length) + (block_size) - 1) / (block_size) * (block_size))
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/** The size of the output of psa_hash_finish(), in bytes.
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*
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* This is also the hash size that psa_hash_verify() expects.
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*
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* \param alg A hash algorithm (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_HASH(\p alg) is true), or an HMAC algorithm
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* (#PSA_ALG_HMAC(\c hash_alg) where \c hash_alg is a
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* hash algorithm).
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*
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* \return The hash size for the specified hash algorithm.
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* If the hash algorithm is not recognized, return 0.
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* An implementation may return either 0 or the correct size
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* for a hash algorithm that it recognizes, but does not support.
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*/
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#define PSA_HASH_SIZE(alg) \
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( \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD2 ? 16 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD4 ? 16 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 16 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 20 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 20 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 28 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 32 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 48 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 64 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 28 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 32 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 28 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 32 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 48 : \
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PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 64 : \
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0)
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/** \def PSA_HASH_MAX_SIZE
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*
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* Maximum size of a hash.
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*
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* This macro must expand to a compile-time constant integer. This value
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* should be the maximum size of a hash supported by the implementation,
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* in bytes, and must be no smaller than this maximum.
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*/
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/* Note: for HMAC-SHA-3, the block size is 144 bytes for HMAC-SHA3-226,
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* 136 bytes for HMAC-SHA3-256, 104 bytes for SHA3-384, 72 bytes for
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* HMAC-SHA3-512. */
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#if defined(MBEDTLS_SHA512_C)
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#define PSA_HASH_MAX_SIZE 64
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#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128
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#else
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#define PSA_HASH_MAX_SIZE 32
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#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64
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#endif
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/** \def PSA_MAC_MAX_SIZE
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*
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* Maximum size of a MAC.
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*
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* This macro must expand to a compile-time constant integer. This value
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* should be the maximum size of a MAC supported by the implementation,
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* in bytes, and must be no smaller than this maximum.
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*/
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/* All non-HMAC MACs have a maximum size that's smaller than the
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* minimum possible value of PSA_HASH_MAX_SIZE in this implementation. */
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/* Note that the encoding of truncated MAC algorithms limits this value
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* to 64 bytes.
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*/
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#define PSA_MAC_MAX_SIZE PSA_HASH_MAX_SIZE
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/** The tag size for an AEAD algorithm, in bytes.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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*
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* \return The tag size for the specified algorithm.
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* If the AEAD algorithm does not have an identified
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* tag that can be distinguished from the rest of
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* the ciphertext, return 0.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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#define PSA_AEAD_TAG_LENGTH(alg) \
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(PSA_ALG_IS_AEAD(alg) ? \
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(((alg) & PSA_ALG_AEAD_TAG_LENGTH_MASK) >> PSA_AEAD_TAG_LENGTH_OFFSET) : \
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0)
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/* The maximum size of an RSA key on this implementation, in bits.
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* This is a vendor-specific macro.
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*
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* Mbed TLS does not set a hard limit on the size of RSA keys: any key
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* whose parameters fit in a bignum is accepted. However large keys can
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* induce a large memory usage and long computation times. Unlike other
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* auxiliary macros in this file and in crypto.h, which reflect how the
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* library is configured, this macro defines how the library is
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* configured. This implementation refuses to import or generate an
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* RSA key whose size is larger than the value defined here.
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*
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* Note that an implementation may set different size limits for different
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* operations, and does not need to accept all key sizes up to the limit. */
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#define PSA_VENDOR_RSA_MAX_KEY_BITS 4096
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/* The maximum size of an ECC key on this implementation, in bits.
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* This is a vendor-specific macro. */
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#if defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 521
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#elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 512
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#elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 448
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#elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384
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#elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384
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#elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256
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#elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256
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#elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256
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#elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 255
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#elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224
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#elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224
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#elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192
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#elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED)
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192
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#else
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#define PSA_VENDOR_ECC_MAX_CURVE_BITS 0
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#endif
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/** \def PSA_ALG_TLS12_PSK_TO_MS_MAX_PSK_LEN
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*
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* This macro returns the maximum length of the PSK supported
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* by the TLS-1.2 PSK-to-MS key derivation.
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*
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* Quoting RFC 4279, Sect 5.3:
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* TLS implementations supporting these ciphersuites MUST support
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* arbitrary PSK identities up to 128 octets in length, and arbitrary
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* PSKs up to 64 octets in length. Supporting longer identities and
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* keys is RECOMMENDED.
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*
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* Therefore, no implementation should define a value smaller than 64
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* for #PSA_ALG_TLS12_PSK_TO_MS_MAX_PSK_LEN.
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*/
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#define PSA_ALG_TLS12_PSK_TO_MS_MAX_PSK_LEN 128
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/** The maximum size of a block cipher supported by the implementation. */
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#define PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE 16
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/** The size of the output of psa_mac_sign_finish(), in bytes.
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*
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* This is also the MAC size that psa_mac_verify_finish() expects.
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*
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* \param key_type The type of the MAC key.
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* \param key_bits The size of the MAC key in bits.
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* \param alg A MAC algorithm (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_MAC(\p alg) is true).
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*
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* \return The MAC size for the specified algorithm with
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* the specified key parameters.
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* \return 0 if the MAC algorithm is not recognized.
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* \return Either 0 or the correct size for a MAC algorithm that
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* the implementation recognizes, but does not support.
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* \return Unspecified if the key parameters are not consistent
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* with the algorithm.
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*/
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#define PSA_MAC_FINAL_SIZE(key_type, key_bits, alg) \
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((alg) & PSA_ALG_MAC_TRUNCATION_MASK ? PSA_MAC_TRUNCATED_LENGTH(alg) : \
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PSA_ALG_IS_HMAC(alg) ? PSA_HASH_SIZE(PSA_ALG_HMAC_GET_HASH(alg)) : \
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PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_SIZE(key_type) : \
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((void)(key_type), (void)(key_bits), 0))
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/** The maximum size of the output of psa_aead_encrypt(), in bytes.
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*
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* If the size of the ciphertext buffer is at least this large, it is
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* guaranteed that psa_aead_encrypt() will not fail due to an
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* insufficient buffer size. Depending on the algorithm, the actual size of
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* the ciphertext may be smaller.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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* \param plaintext_length Size of the plaintext in bytes.
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*
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* \return The AEAD ciphertext size for the specified
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* algorithm.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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#define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(alg, plaintext_length) \
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(PSA_AEAD_TAG_LENGTH(alg) != 0 ? \
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(plaintext_length) + PSA_AEAD_TAG_LENGTH(alg) : \
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0)
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/** The maximum size of the output of psa_aead_decrypt(), in bytes.
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*
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* If the size of the plaintext buffer is at least this large, it is
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* guaranteed that psa_aead_decrypt() will not fail due to an
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* insufficient buffer size. Depending on the algorithm, the actual size of
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* the plaintext may be smaller.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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* \param ciphertext_length Size of the plaintext in bytes.
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*
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* \return The AEAD ciphertext size for the specified
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* algorithm.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(alg, ciphertext_length) \
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(PSA_AEAD_TAG_LENGTH(alg) != 0 ? \
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(ciphertext_length) - PSA_AEAD_TAG_LENGTH(alg) : \
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0)
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/** A sufficient output buffer size for psa_aead_update().
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*
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* If the size of the output buffer is at least this large, it is
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* guaranteed that psa_aead_update() will not fail due to an
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* insufficient buffer size. The actual size of the output may be smaller
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* in any given call.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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* \param input_length Size of the input in bytes.
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*
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* \return A sufficient output buffer size for the specified
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* algorithm.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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/* For all the AEAD modes defined in this specification, it is possible
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* to emit output without delay. However, hardware may not always be
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* capable of this. So for modes based on a block cipher, allow the
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* implementation to delay the output until it has a full block. */
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#define PSA_AEAD_UPDATE_OUTPUT_SIZE(alg, input_length) \
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(PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
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PSA_ROUND_UP_TO_MULTIPLE(PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE, (input_length)) : \
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(input_length))
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/** A sufficient ciphertext buffer size for psa_aead_finish().
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*
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* If the size of the ciphertext buffer is at least this large, it is
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* guaranteed that psa_aead_finish() will not fail due to an
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* insufficient ciphertext buffer size. The actual size of the output may
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* be smaller in any given call.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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*
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* \return A sufficient ciphertext buffer size for the
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* specified algorithm.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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#define PSA_AEAD_FINISH_OUTPUT_SIZE(alg) \
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(PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
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PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE : \
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0)
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/** A sufficient plaintext buffer size for psa_aead_verify().
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*
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* If the size of the plaintext buffer is at least this large, it is
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* guaranteed that psa_aead_verify() will not fail due to an
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* insufficient plaintext buffer size. The actual size of the output may
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* be smaller in any given call.
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*
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* \param alg An AEAD algorithm
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* (\c PSA_ALG_XXX value such that
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* #PSA_ALG_IS_AEAD(\p alg) is true).
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*
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* \return A sufficient plaintext buffer size for the
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* specified algorithm.
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* If the AEAD algorithm is not recognized, return 0.
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* An implementation may return either 0 or a
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* correct size for an AEAD algorithm that it
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* recognizes, but does not support.
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*/
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#define PSA_AEAD_VERIFY_OUTPUT_SIZE(alg) \
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(PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
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PSA_MAX_BLOCK_CIPHER_BLOCK_SIZE : \
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0)
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#define PSA_RSA_MINIMUM_PADDING_SIZE(alg) \
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(PSA_ALG_IS_RSA_OAEP(alg) ? \
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2 * PSA_HASH_SIZE(PSA_ALG_RSA_OAEP_GET_HASH(alg)) + 1 : \
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11 /*PKCS#1v1.5*/)
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/**
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* \brief ECDSA signature size for a given curve bit size
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*
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* \param curve_bits Curve size in bits.
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* \return Signature size in bytes.
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*
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* \note This macro returns a compile-time constant if its argument is one.
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*/
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#define PSA_ECDSA_SIGNATURE_SIZE(curve_bits) \
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(PSA_BITS_TO_BYTES(curve_bits) * 2)
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/** Sufficient signature buffer size for psa_sign_hash().
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*
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* This macro returns a sufficient buffer size for a signature using a key
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* of the specified type and size, with the specified algorithm.
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* Note that the actual size of the signature may be smaller
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* (some algorithms produce a variable-size signature).
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*
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* \warning This function may call its arguments multiple times or
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* zero times, so you should not pass arguments that contain
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* side effects.
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*
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* \param key_type An asymmetric key type (this may indifferently be a
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* key pair type or a public key type).
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* \param key_bits The size of the key in bits.
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* \param alg The signature algorithm.
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*
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* \return If the parameters are valid and supported, return
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* a buffer size in bytes that guarantees that
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* psa_sign_hash() will not fail with
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* #PSA_ERROR_BUFFER_TOO_SMALL.
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* If the parameters are a valid combination that is not supported
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* by the implementation, this macro shall return either a
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* sensible size or 0.
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* If the parameters are not valid, the
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* return value is unspecified.
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*/
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#define PSA_SIGN_OUTPUT_SIZE(key_type, key_bits, alg) \
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(PSA_KEY_TYPE_IS_RSA(key_type) ? ((void)alg, PSA_BITS_TO_BYTES(key_bits)) : \
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PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_ECDSA_SIGNATURE_SIZE(key_bits) : \
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((void)alg, 0))
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#define PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE \
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PSA_ECDSA_SIGNATURE_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)
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/** \def PSA_SIGNATURE_MAX_SIZE
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*
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* Maximum size of an asymmetric signature.
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*
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* This macro must expand to a compile-time constant integer. This value
|
|
* should be the maximum size of a signature supported by the implementation,
|
|
* in bytes, and must be no smaller than this maximum.
|
|
*/
|
|
#define PSA_SIGNATURE_MAX_SIZE \
|
|
(PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) > PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE ? \
|
|
PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) : \
|
|
PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE)
|
|
|
|
/** Sufficient output buffer size for psa_asymmetric_encrypt().
|
|
*
|
|
* This macro returns a sufficient buffer size for a ciphertext produced using
|
|
* a key of the specified type and size, with the specified algorithm.
|
|
* Note that the actual size of the ciphertext may be smaller, depending
|
|
* on the algorithm.
|
|
*
|
|
* \warning This function may call its arguments multiple times or
|
|
* zero times, so you should not pass arguments that contain
|
|
* side effects.
|
|
*
|
|
* \param key_type An asymmetric key type (this may indifferently be a
|
|
* key pair type or a public key type).
|
|
* \param key_bits The size of the key in bits.
|
|
* \param alg The signature algorithm.
|
|
*
|
|
* \return If the parameters are valid and supported, return
|
|
* a buffer size in bytes that guarantees that
|
|
* psa_asymmetric_encrypt() will not fail with
|
|
* #PSA_ERROR_BUFFER_TOO_SMALL.
|
|
* If the parameters are a valid combination that is not supported
|
|
* by the implementation, this macro shall return either a
|
|
* sensible size or 0.
|
|
* If the parameters are not valid, the
|
|
* return value is unspecified.
|
|
*/
|
|
#define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \
|
|
(PSA_KEY_TYPE_IS_RSA(key_type) ? \
|
|
((void)alg, PSA_BITS_TO_BYTES(key_bits)) : \
|
|
0)
|
|
|
|
/** Sufficient output buffer size for psa_asymmetric_decrypt().
|
|
*
|
|
* This macro returns a sufficient buffer size for a ciphertext produced using
|
|
* a key of the specified type and size, with the specified algorithm.
|
|
* Note that the actual size of the ciphertext may be smaller, depending
|
|
* on the algorithm.
|
|
*
|
|
* \warning This function may call its arguments multiple times or
|
|
* zero times, so you should not pass arguments that contain
|
|
* side effects.
|
|
*
|
|
* \param key_type An asymmetric key type (this may indifferently be a
|
|
* key pair type or a public key type).
|
|
* \param key_bits The size of the key in bits.
|
|
* \param alg The signature algorithm.
|
|
*
|
|
* \return If the parameters are valid and supported, return
|
|
* a buffer size in bytes that guarantees that
|
|
* psa_asymmetric_decrypt() will not fail with
|
|
* #PSA_ERROR_BUFFER_TOO_SMALL.
|
|
* If the parameters are a valid combination that is not supported
|
|
* by the implementation, this macro shall return either a
|
|
* sensible size or 0.
|
|
* If the parameters are not valid, the
|
|
* return value is unspecified.
|
|
*/
|
|
#define PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \
|
|
(PSA_KEY_TYPE_IS_RSA(key_type) ? \
|
|
PSA_BITS_TO_BYTES(key_bits) - PSA_RSA_MINIMUM_PADDING_SIZE(alg) : \
|
|
0)
|
|
|
|
/* Maximum size of the ASN.1 encoding of an INTEGER with the specified
|
|
* number of bits.
|
|
*
|
|
* This definition assumes that bits <= 2^19 - 9 so that the length field
|
|
* is at most 3 bytes. The length of the encoding is the length of the
|
|
* bit string padded to a whole number of bytes plus:
|
|
* - 1 type byte;
|
|
* - 1 to 3 length bytes;
|
|
* - 0 to 1 bytes of leading 0 due to the sign bit.
|
|
*/
|
|
#define PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(bits) \
|
|
((bits) / 8 + 5)
|
|
|
|
/* Maximum size of the export encoding of an RSA public key.
|
|
* Assumes that the public exponent is less than 2^32.
|
|
*
|
|
* RSAPublicKey ::= SEQUENCE {
|
|
* modulus INTEGER, -- n
|
|
* publicExponent INTEGER } -- e
|
|
*
|
|
* - 4 bytes of SEQUENCE overhead;
|
|
* - n : INTEGER;
|
|
* - 7 bytes for the public exponent.
|
|
*/
|
|
#define PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) \
|
|
(PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) + 11)
|
|
|
|
/* Maximum size of the export encoding of an RSA key pair.
|
|
* Assumes thatthe public exponent is less than 2^32 and that the size
|
|
* difference between the two primes is at most 1 bit.
|
|
*
|
|
* RSAPrivateKey ::= SEQUENCE {
|
|
* version Version, -- 0
|
|
* modulus INTEGER, -- N-bit
|
|
* publicExponent INTEGER, -- 32-bit
|
|
* privateExponent INTEGER, -- N-bit
|
|
* prime1 INTEGER, -- N/2-bit
|
|
* prime2 INTEGER, -- N/2-bit
|
|
* exponent1 INTEGER, -- N/2-bit
|
|
* exponent2 INTEGER, -- N/2-bit
|
|
* coefficient INTEGER, -- N/2-bit
|
|
* }
|
|
*
|
|
* - 4 bytes of SEQUENCE overhead;
|
|
* - 3 bytes of version;
|
|
* - 7 half-size INTEGERs plus 2 full-size INTEGERs,
|
|
* overapproximated as 9 half-size INTEGERS;
|
|
* - 7 bytes for the public exponent.
|
|
*/
|
|
#define PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) \
|
|
(9 * PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE((key_bits) / 2 + 1) + 14)
|
|
|
|
/* Maximum size of the export encoding of a DSA public key.
|
|
*
|
|
* SubjectPublicKeyInfo ::= SEQUENCE {
|
|
* algorithm AlgorithmIdentifier,
|
|
* subjectPublicKey BIT STRING } -- contains DSAPublicKey
|
|
* AlgorithmIdentifier ::= SEQUENCE {
|
|
* algorithm OBJECT IDENTIFIER,
|
|
* parameters Dss-Parms } -- SEQUENCE of 3 INTEGERs
|
|
* DSAPublicKey ::= INTEGER -- public key, Y
|
|
*
|
|
* - 3 * 4 bytes of SEQUENCE overhead;
|
|
* - 1 + 1 + 7 bytes of algorithm (DSA OID);
|
|
* - 4 bytes of BIT STRING overhead;
|
|
* - 3 full-size INTEGERs (p, g, y);
|
|
* - 1 + 1 + 32 bytes for 1 sub-size INTEGER (q <= 256 bits).
|
|
*/
|
|
#define PSA_KEY_EXPORT_DSA_PUBLIC_KEY_MAX_SIZE(key_bits) \
|
|
(PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3 + 59)
|
|
|
|
/* Maximum size of the export encoding of a DSA key pair.
|
|
*
|
|
* DSAPrivateKey ::= SEQUENCE {
|
|
* version Version, -- 0
|
|
* prime INTEGER, -- p
|
|
* subprime INTEGER, -- q
|
|
* generator INTEGER, -- g
|
|
* public INTEGER, -- y
|
|
* private INTEGER, -- x
|
|
* }
|
|
*
|
|
* - 4 bytes of SEQUENCE overhead;
|
|
* - 3 bytes of version;
|
|
* - 3 full-size INTEGERs (p, g, y);
|
|
* - 2 * (1 + 1 + 32) bytes for 2 sub-size INTEGERs (q, x <= 256 bits).
|
|
*/
|
|
#define PSA_KEY_EXPORT_DSA_KEY_PAIR_MAX_SIZE(key_bits) \
|
|
(PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3 + 75)
|
|
|
|
/* Maximum size of the export encoding of an ECC public key.
|
|
*
|
|
* The representation of an ECC public key is:
|
|
* - The byte 0x04;
|
|
* - `x_P` as a `ceiling(m/8)`-byte string, big-endian;
|
|
* - `y_P` as a `ceiling(m/8)`-byte string, big-endian;
|
|
* - where m is the bit size associated with the curve.
|
|
*
|
|
* - 1 byte + 2 * point size.
|
|
*/
|
|
#define PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) \
|
|
(2 * PSA_BITS_TO_BYTES(key_bits) + 1)
|
|
|
|
/* Maximum size of the export encoding of an ECC key pair.
|
|
*
|
|
* An ECC key pair is represented by the secret value.
|
|
*/
|
|
#define PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) \
|
|
(PSA_BITS_TO_BYTES(key_bits))
|
|
|
|
/** Sufficient output buffer size for psa_export_key() or psa_export_public_key().
|
|
*
|
|
* This macro returns a compile-time constant if its arguments are
|
|
* compile-time constants.
|
|
*
|
|
* \warning This function may call its arguments multiple times or
|
|
* zero times, so you should not pass arguments that contain
|
|
* side effects.
|
|
*
|
|
* The following code illustrates how to allocate enough memory to export
|
|
* a key by querying the key type and size at runtime.
|
|
* \code{c}
|
|
* psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
|
|
* psa_status_t status;
|
|
* status = psa_get_key_attributes(key, &attributes);
|
|
* if (status != PSA_SUCCESS) handle_error(...);
|
|
* psa_key_type_t key_type = psa_get_key_type(&attributes);
|
|
* size_t key_bits = psa_get_key_bits(&attributes);
|
|
* size_t buffer_size = PSA_KEY_EXPORT_MAX_SIZE(key_type, key_bits);
|
|
* psa_reset_key_attributes(&attributes);
|
|
* uint8_t *buffer = malloc(buffer_size);
|
|
* if (buffer == NULL) handle_error(...);
|
|
* size_t buffer_length;
|
|
* status = psa_export_key(key, buffer, buffer_size, &buffer_length);
|
|
* if (status != PSA_SUCCESS) handle_error(...);
|
|
* \endcode
|
|
*
|
|
* For psa_export_public_key(), calculate the buffer size from the
|
|
* public key type. You can use the macro #PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR
|
|
* to convert a key pair type to the corresponding public key type.
|
|
* \code{c}
|
|
* psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
|
|
* psa_status_t status;
|
|
* status = psa_get_key_attributes(key, &attributes);
|
|
* if (status != PSA_SUCCESS) handle_error(...);
|
|
* psa_key_type_t key_type = psa_get_key_type(&attributes);
|
|
* psa_key_type_t public_key_type = PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR(key_type);
|
|
* size_t key_bits = psa_get_key_bits(&attributes);
|
|
* size_t buffer_size = PSA_KEY_EXPORT_MAX_SIZE(public_key_type, key_bits);
|
|
* psa_reset_key_attributes(&attributes);
|
|
* uint8_t *buffer = malloc(buffer_size);
|
|
* if (buffer == NULL) handle_error(...);
|
|
* size_t buffer_length;
|
|
* status = psa_export_public_key(key, buffer, buffer_size, &buffer_length);
|
|
* if (status != PSA_SUCCESS) handle_error(...);
|
|
* \endcode
|
|
*
|
|
* \param key_type A supported key type.
|
|
* \param key_bits The size of the key in bits.
|
|
*
|
|
* \return If the parameters are valid and supported, return
|
|
* a buffer size in bytes that guarantees that
|
|
* psa_sign_hash() will not fail with
|
|
* #PSA_ERROR_BUFFER_TOO_SMALL.
|
|
* If the parameters are a valid combination that is not supported
|
|
* by the implementation, this macro shall return either a
|
|
* sensible size or 0.
|
|
* If the parameters are not valid, the
|
|
* return value is unspecified.
|
|
*/
|
|
#define PSA_KEY_EXPORT_MAX_SIZE(key_type, key_bits) \
|
|
(PSA_KEY_TYPE_IS_UNSTRUCTURED(key_type) ? PSA_BITS_TO_BYTES(key_bits) : \
|
|
(key_type) == PSA_KEY_TYPE_RSA_KEY_PAIR ? PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) : \
|
|
(key_type) == PSA_KEY_TYPE_RSA_PUBLIC_KEY ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \
|
|
(key_type) == PSA_KEY_TYPE_DSA_KEY_PAIR ? PSA_KEY_EXPORT_DSA_KEY_PAIR_MAX_SIZE(key_bits) : \
|
|
(key_type) == PSA_KEY_TYPE_DSA_PUBLIC_KEY ? PSA_KEY_EXPORT_DSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \
|
|
PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) ? PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) : \
|
|
PSA_KEY_TYPE_IS_ECC_PUBLIC_KEY(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \
|
|
0)
|
|
|
|
#endif /* PSA_CRYPTO_SIZES_H */
|