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diff --git a/include/psa/crypto_sizes.h b/include/psa/crypto_sizes.h new file mode 100644 index 0000000..d22bf10 --- /dev/null +++ b/include/psa/crypto_sizes.h @@ -0,0 +1,1282 @@ +/** + * \file psa/crypto_sizes.h + * + * \brief PSA cryptography module: Mbed TLS buffer size macros + * + * \note This file may not be included directly. Applications must + * include psa/crypto.h. + * + * This file contains the definitions of macros that are useful to + * compute buffer sizes. The signatures and semantics of these macros + * are standardized, but the definitions are not, because they depend on + * the available algorithms and, in some cases, on permitted tolerances + * on buffer sizes. + * + * In implementations with isolation between the application and the + * cryptography module, implementers should take care to ensure that + * the definitions that are exposed to applications match what the + * module implements. + * + * Macros that compute sizes whose values do not depend on the + * implementation are in crypto.h. + */ +/* + * Copyright The Mbed TLS Contributors + * SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later + */ + +#ifndef PSA_CRYPTO_SIZES_H +#define PSA_CRYPTO_SIZES_H + +/* + * Include the build-time configuration information file. Here, we do not + * include `"mbedtls/build_info.h"` directly but `"psa/build_info.h"`, which + * is basically just an alias to it. This is to ease the maintenance of the + * PSA cryptography repository which has a different build system and + * configuration. + */ +#include "psa/build_info.h" + +#define PSA_BITS_TO_BYTES(bits) (((bits) + 7u) / 8u) +#define PSA_BYTES_TO_BITS(bytes) ((bytes) * 8u) +#define PSA_MAX_OF_THREE(a, b, c) ((a) <= (b) ? (b) <= (c) ? \ + (c) : (b) : (a) <= (c) ? (c) : (a)) + +#define PSA_ROUND_UP_TO_MULTIPLE(block_size, length) \ + (((length) + (block_size) - 1) / (block_size) * (block_size)) + +/** The size of the output of psa_hash_finish(), in bytes. + * + * This is also the hash size that psa_hash_verify() expects. + * + * \param alg A hash algorithm (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_HASH(\p alg) is true), or an HMAC algorithm + * (#PSA_ALG_HMAC(\c hash_alg) where \c hash_alg is a + * hash algorithm). + * + * \return The hash size for the specified hash algorithm. + * If the hash algorithm is not recognized, return 0. + */ +#define PSA_HASH_LENGTH(alg) \ + ( \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 16u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 20u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 20u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 28u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 32u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 48u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 28u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 32u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 28u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 32u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 48u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 64u : \ + 0u) + +/** The input block size of a hash algorithm, in bytes. + * + * Hash algorithms process their input data in blocks. Hash operations will + * retain any partial blocks until they have enough input to fill the block or + * until the operation is finished. + * This affects the output from psa_hash_suspend(). + * + * \param alg A hash algorithm (\c PSA_ALG_XXX value such that + * PSA_ALG_IS_HASH(\p alg) is true). + * + * \return The block size in bytes for the specified hash algorithm. + * If the hash algorithm is not recognized, return 0. + * An implementation can return either 0 or the correct size for a + * hash algorithm that it recognizes, but does not support. + */ +#define PSA_HASH_BLOCK_LENGTH(alg) \ + ( \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 64u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 128u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 128u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 128u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 128u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 144u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 136u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 104u : \ + PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 72u : \ + 0u) + +/** \def PSA_HASH_MAX_SIZE + * + * Maximum size of a hash. + * + * This macro expands to a compile-time constant integer. This value + * is the maximum size of a hash in bytes. + */ +/* Note: for HMAC-SHA-3, the block size is 144 bytes for HMAC-SHA3-224, + * 136 bytes for HMAC-SHA3-256, 104 bytes for SHA3-384, 72 bytes for + * HMAC-SHA3-512. */ +/* Note: PSA_HASH_MAX_SIZE should be kept in sync with MBEDTLS_MD_MAX_SIZE, + * see the note on MBEDTLS_MD_MAX_SIZE for details. */ +#if defined(PSA_WANT_ALG_SHA3_224) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 144u +#elif defined(PSA_WANT_ALG_SHA3_256) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 136u +#elif defined(PSA_WANT_ALG_SHA_512) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128u +#elif defined(PSA_WANT_ALG_SHA_384) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128u +#elif defined(PSA_WANT_ALG_SHA3_384) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 104u +#elif defined(PSA_WANT_ALG_SHA3_512) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 72u +#elif defined(PSA_WANT_ALG_SHA_256) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u +#elif defined(PSA_WANT_ALG_SHA_224) +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u +#else /* SHA-1 or smaller */ +#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u +#endif + +#if defined(PSA_WANT_ALG_SHA_512) || defined(PSA_WANT_ALG_SHA3_512) +#define PSA_HASH_MAX_SIZE 64u +#elif defined(PSA_WANT_ALG_SHA_384) || defined(PSA_WANT_ALG_SHA3_384) +#define PSA_HASH_MAX_SIZE 48u +#elif defined(PSA_WANT_ALG_SHA_256) || defined(PSA_WANT_ALG_SHA3_256) +#define PSA_HASH_MAX_SIZE 32u +#elif defined(PSA_WANT_ALG_SHA_224) || defined(PSA_WANT_ALG_SHA3_224) +#define PSA_HASH_MAX_SIZE 28u +#else /* SHA-1 or smaller */ +#define PSA_HASH_MAX_SIZE 20u +#endif + +/** \def PSA_MAC_MAX_SIZE + * + * Maximum size of a MAC. + * + * This macro expands to a compile-time constant integer. This value + * is the maximum size of a MAC in bytes. + */ +/* All non-HMAC MACs have a maximum size that's smaller than the + * minimum possible value of PSA_HASH_MAX_SIZE in this implementation. */ +/* Note that the encoding of truncated MAC algorithms limits this value + * to 64 bytes. + */ +#define PSA_MAC_MAX_SIZE PSA_HASH_MAX_SIZE + +/** The length of a tag for an AEAD algorithm, in bytes. + * + * This macro can be used to allocate a buffer of sufficient size to store the + * tag output from psa_aead_finish(). + * + * See also #PSA_AEAD_TAG_MAX_SIZE. + * + * \param key_type The type of the AEAD key. + * \param key_bits The size of the AEAD key in bits. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * + * \return The tag length for the specified algorithm and key. + * If the AEAD algorithm does not have an identified + * tag that can be distinguished from the rest of + * the ciphertext, return 0. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_AEAD_TAG_LENGTH(key_type, key_bits, alg) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \ + PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \ + ((void) (key_bits), 0u)) + +/** The maximum tag size for all supported AEAD algorithms, in bytes. + * + * See also #PSA_AEAD_TAG_LENGTH(\p key_type, \p key_bits, \p alg). + */ +#define PSA_AEAD_TAG_MAX_SIZE 16u + +/* The maximum size of an RSA key on this implementation, in bits. + * This is a vendor-specific macro. + * + * Mbed TLS does not set a hard limit on the size of RSA keys: any key + * whose parameters fit in a bignum is accepted. However large keys can + * induce a large memory usage and long computation times. Unlike other + * auxiliary macros in this file and in crypto.h, which reflect how the + * library is configured, this macro defines how the library is + * configured. This implementation refuses to import or generate an + * RSA key whose size is larger than the value defined here. + * + * Note that an implementation may set different size limits for different + * operations, and does not need to accept all key sizes up to the limit. */ +#define PSA_VENDOR_RSA_MAX_KEY_BITS 4096u + +/* The minimum size of an RSA key on this implementation, in bits. + * This is a vendor-specific macro. + * + * Limits RSA key generation to a minimum due to avoid accidental misuse. + * This value cannot be less than 128 bits. + */ +#if defined(MBEDTLS_RSA_GEN_KEY_MIN_BITS) +#define PSA_VENDOR_RSA_GENERATE_MIN_KEY_BITS MBEDTLS_RSA_GEN_KEY_MIN_BITS +#else +#define PSA_VENDOR_RSA_GENERATE_MIN_KEY_BITS 1024 +#endif + +/* The maximum size of an DH key on this implementation, in bits. + * + * Note that an implementation may set different size limits for different + * operations, and does not need to accept all key sizes up to the limit. */ +#define PSA_VENDOR_FFDH_MAX_KEY_BITS 8192u + +/* The maximum size of an ECC key on this implementation, in bits. + * This is a vendor-specific macro. */ +#if defined(PSA_WANT_ECC_SECP_R1_521) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 521u +#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_512) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 512u +#elif defined(PSA_WANT_ECC_MONTGOMERY_448) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 448u +#elif defined(PSA_WANT_ECC_SECP_R1_384) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384u +#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_384) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384u +#elif defined(PSA_WANT_ECC_SECP_R1_256) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u +#elif defined(PSA_WANT_ECC_SECP_K1_256) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u +#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_256) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u +#elif defined(PSA_WANT_ECC_MONTGOMERY_255) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 255u +#elif defined(PSA_WANT_ECC_SECP_R1_224) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224u +#elif defined(PSA_WANT_ECC_SECP_K1_224) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224u +#elif defined(PSA_WANT_ECC_SECP_R1_192) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192u +#elif defined(PSA_WANT_ECC_SECP_K1_192) +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192u +#else +#define PSA_VENDOR_ECC_MAX_CURVE_BITS 0u +#endif + +/** This macro returns the maximum supported length of the PSK for the + * TLS-1.2 PSK-to-MS key derivation + * (#PSA_ALG_TLS12_PSK_TO_MS(\c hash_alg)). + * + * The maximum supported length does not depend on the chosen hash algorithm. + * + * Quoting RFC 4279, Sect 5.3: + * TLS implementations supporting these ciphersuites MUST support + * arbitrary PSK identities up to 128 octets in length, and arbitrary + * PSKs up to 64 octets in length. Supporting longer identities and + * keys is RECOMMENDED. + * + * Therefore, no implementation should define a value smaller than 64 + * for #PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE. + */ +#define PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE 128u + +/* The expected size of input passed to psa_tls12_ecjpake_to_pms_input, + * which is expected to work with P-256 curve only. */ +#define PSA_TLS12_ECJPAKE_TO_PMS_INPUT_SIZE 65u + +/* The size of a serialized K.X coordinate to be used in + * psa_tls12_ecjpake_to_pms_input. This function only accepts the P-256 + * curve. */ +#define PSA_TLS12_ECJPAKE_TO_PMS_DATA_SIZE 32u + +/* The maximum number of iterations for PBKDF2 on this implementation, in bits. + * This is a vendor-specific macro. This can be configured if necessary */ +#define PSA_VENDOR_PBKDF2_MAX_ITERATIONS 0xffffffffU + +/** The maximum size of a block cipher. */ +#define PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE 16u + +/** The size of the output of psa_mac_sign_finish(), in bytes. + * + * This is also the MAC size that psa_mac_verify_finish() expects. + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type The type of the MAC key. + * \param key_bits The size of the MAC key in bits. + * \param alg A MAC algorithm (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_MAC(\p alg) is true). + * + * \return The MAC size for the specified algorithm with + * the specified key parameters. + * \return 0 if the MAC algorithm is not recognized. + * \return Either 0 or the correct size for a MAC algorithm that + * the implementation recognizes, but does not support. + * \return Unspecified if the key parameters are not consistent + * with the algorithm. + */ +#define PSA_MAC_LENGTH(key_type, key_bits, alg) \ + ((alg) & PSA_ALG_MAC_TRUNCATION_MASK ? PSA_MAC_TRUNCATED_LENGTH(alg) : \ + PSA_ALG_IS_HMAC(alg) ? PSA_HASH_LENGTH(PSA_ALG_HMAC_GET_HASH(alg)) : \ + PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ + ((void) (key_type), (void) (key_bits), 0u)) + +/** The maximum size of the output of psa_aead_encrypt(), in bytes. + * + * If the size of the ciphertext buffer is at least this large, it is + * guaranteed that psa_aead_encrypt() will not fail due to an + * insufficient buffer size. Depending on the algorithm, the actual size of + * the ciphertext may be smaller. + * + * See also #PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(\p plaintext_length). + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is + * compatible with algorithm \p alg. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * \param plaintext_length Size of the plaintext in bytes. + * + * \return The AEAD ciphertext size for the specified + * algorithm. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(key_type, alg, plaintext_length) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \ + (plaintext_length) + PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \ + 0u) + +/** A sufficient output buffer size for psa_aead_encrypt(), for any of the + * supported key types and AEAD algorithms. + * + * If the size of the ciphertext buffer is at least this large, it is guaranteed + * that psa_aead_encrypt() will not fail due to an insufficient buffer size. + * + * \note This macro returns a compile-time constant if its arguments are + * compile-time constants. + * + * See also #PSA_AEAD_ENCRYPT_OUTPUT_SIZE(\p key_type, \p alg, + * \p plaintext_length). + * + * \param plaintext_length Size of the plaintext in bytes. + * + * \return A sufficient output buffer size for any of the + * supported key types and AEAD algorithms. + * + */ +#define PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(plaintext_length) \ + ((plaintext_length) + PSA_AEAD_TAG_MAX_SIZE) + + +/** The maximum size of the output of psa_aead_decrypt(), in bytes. + * + * If the size of the plaintext buffer is at least this large, it is + * guaranteed that psa_aead_decrypt() will not fail due to an + * insufficient buffer size. Depending on the algorithm, the actual size of + * the plaintext may be smaller. + * + * See also #PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(\p ciphertext_length). + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is + * compatible with algorithm \p alg. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * \param ciphertext_length Size of the plaintext in bytes. + * + * \return The AEAD ciphertext size for the specified + * algorithm. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(key_type, alg, ciphertext_length) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \ + (ciphertext_length) > PSA_ALG_AEAD_GET_TAG_LENGTH(alg) ? \ + (ciphertext_length) - PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \ + 0u) + +/** A sufficient output buffer size for psa_aead_decrypt(), for any of the + * supported key types and AEAD algorithms. + * + * If the size of the plaintext buffer is at least this large, it is guaranteed + * that psa_aead_decrypt() will not fail due to an insufficient buffer size. + * + * \note This macro returns a compile-time constant if its arguments are + * compile-time constants. + * + * See also #PSA_AEAD_DECRYPT_OUTPUT_SIZE(\p key_type, \p alg, + * \p ciphertext_length). + * + * \param ciphertext_length Size of the ciphertext in bytes. + * + * \return A sufficient output buffer size for any of the + * supported key types and AEAD algorithms. + * + */ +#define PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(ciphertext_length) \ + (ciphertext_length) + +/** The default nonce size for an AEAD algorithm, in bytes. + * + * This macro can be used to allocate a buffer of sufficient size to + * store the nonce output from #psa_aead_generate_nonce(). + * + * See also #PSA_AEAD_NONCE_MAX_SIZE. + * + * \note This is not the maximum size of nonce supported as input to + * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(), + * just the default size that is generated by #psa_aead_generate_nonce(). + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is compatible with + * algorithm \p alg. + * + * \param alg An AEAD algorithm (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * + * \return The default nonce size for the specified key type and algorithm. + * If the key type or AEAD algorithm is not recognized, + * or the parameters are incompatible, return 0. + */ +#define PSA_AEAD_NONCE_LENGTH(key_type, alg) \ + (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) == 16 ? \ + MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_CCM) ? 13u : \ + MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_GCM) ? 12u : \ + 0u : \ + (key_type) == PSA_KEY_TYPE_CHACHA20 && \ + MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_CHACHA20_POLY1305) ? 12u : \ + 0u) + +/** The maximum default nonce size among all supported pairs of key types and + * AEAD algorithms, in bytes. + * + * This is equal to or greater than any value that #PSA_AEAD_NONCE_LENGTH() + * may return. + * + * \note This is not the maximum size of nonce supported as input to + * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(), + * just the largest size that may be generated by + * #psa_aead_generate_nonce(). + */ +#define PSA_AEAD_NONCE_MAX_SIZE 13u + +/** A sufficient output buffer size for psa_aead_update(). + * + * If the size of the output buffer is at least this large, it is + * guaranteed that psa_aead_update() will not fail due to an + * insufficient buffer size. The actual size of the output may be smaller + * in any given call. + * + * See also #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p input_length). + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is + * compatible with algorithm \p alg. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * \param input_length Size of the input in bytes. + * + * \return A sufficient output buffer size for the specified + * algorithm. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +/* For all the AEAD modes defined in this specification, it is possible + * to emit output without delay. However, hardware may not always be + * capable of this. So for modes based on a block cipher, allow the + * implementation to delay the output until it has a full block. */ +#define PSA_AEAD_UPDATE_OUTPUT_SIZE(key_type, alg, input_length) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \ + PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ + PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), (input_length)) : \ + (input_length) : \ + 0u) + +/** A sufficient output buffer size for psa_aead_update(), for any of the + * supported key types and AEAD algorithms. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_aead_update() will not fail due to an insufficient buffer size. + * + * See also #PSA_AEAD_UPDATE_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). + * + * \param input_length Size of the input in bytes. + */ +#define PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(input_length) \ + (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, (input_length))) + +/** A sufficient ciphertext buffer size for psa_aead_finish(). + * + * If the size of the ciphertext buffer is at least this large, it is + * guaranteed that psa_aead_finish() will not fail due to an + * insufficient ciphertext buffer size. The actual size of the output may + * be smaller in any given call. + * + * See also #PSA_AEAD_FINISH_OUTPUT_MAX_SIZE. + * + * \param key_type A symmetric key type that is + compatible with algorithm \p alg. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * + * \return A sufficient ciphertext buffer size for the + * specified algorithm. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_AEAD_FINISH_OUTPUT_SIZE(key_type, alg) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \ + PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ + PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ + 0u) + +/** A sufficient ciphertext buffer size for psa_aead_finish(), for any of the + * supported key types and AEAD algorithms. + * + * See also #PSA_AEAD_FINISH_OUTPUT_SIZE(\p key_type, \p alg). + */ +#define PSA_AEAD_FINISH_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) + +/** A sufficient plaintext buffer size for psa_aead_verify(). + * + * If the size of the plaintext buffer is at least this large, it is + * guaranteed that psa_aead_verify() will not fail due to an + * insufficient plaintext buffer size. The actual size of the output may + * be smaller in any given call. + * + * See also #PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE. + * + * \param key_type A symmetric key type that is + * compatible with algorithm \p alg. + * \param alg An AEAD algorithm + * (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_AEAD(\p alg) is true). + * + * \return A sufficient plaintext buffer size for the + * specified algorithm. + * If the key type or AEAD algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_AEAD_VERIFY_OUTPUT_SIZE(key_type, alg) \ + (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \ + PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ + PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ + 0u) + +/** A sufficient plaintext buffer size for psa_aead_verify(), for any of the + * supported key types and AEAD algorithms. + * + * See also #PSA_AEAD_VERIFY_OUTPUT_SIZE(\p key_type, \p alg). + */ +#define PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) + +#define PSA_RSA_MINIMUM_PADDING_SIZE(alg) \ + (PSA_ALG_IS_RSA_OAEP(alg) ? \ + 2u * PSA_HASH_LENGTH(PSA_ALG_RSA_OAEP_GET_HASH(alg)) + 1u : \ + 11u /*PKCS#1v1.5*/) + +/** + * \brief ECDSA signature size for a given curve bit size + * + * \param curve_bits Curve size in bits. + * \return Signature size in bytes. + * + * \note This macro returns a compile-time constant if its argument is one. + */ +#define PSA_ECDSA_SIGNATURE_SIZE(curve_bits) \ + (PSA_BITS_TO_BYTES(curve_bits) * 2u) + +/** Sufficient signature buffer size for psa_sign_hash(). + * + * This macro returns a sufficient buffer size for a signature using a key + * of the specified type and size, with the specified algorithm. + * Note that the actual size of the signature may be smaller + * (some algorithms produce a variable-size signature). + * + * \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_sign_hash() will not fail with + * #PSA_ERROR_BUFFER_TOO_SMALL. + * If the parameters are a valid combination that is not supported, + * return either a sensible size or 0. + * If the parameters are not valid, the + * return value is unspecified. + */ +#define PSA_SIGN_OUTPUT_SIZE(key_type, key_bits, alg) \ + (PSA_KEY_TYPE_IS_RSA(key_type) ? ((void) alg, PSA_BITS_TO_BYTES(key_bits)) : \ + PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_ECDSA_SIGNATURE_SIZE(key_bits) : \ + ((void) alg, 0u)) + +#define PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE \ + PSA_ECDSA_SIGNATURE_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) + +/** \def PSA_SIGNATURE_MAX_SIZE + * + * Maximum size of an asymmetric signature. + * + * This macro expands to a compile-time constant integer. This value + * is the maximum size of a signature in bytes. + */ +#define PSA_SIGNATURE_MAX_SIZE 1 + +#if (defined(PSA_WANT_ALG_ECDSA) || defined(PSA_WANT_ALG_DETERMINISTIC_ECDSA)) && \ + (PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE > PSA_SIGNATURE_MAX_SIZE) +#undef PSA_SIGNATURE_MAX_SIZE +#define PSA_SIGNATURE_MAX_SIZE PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE +#endif +#if (defined(PSA_WANT_ALG_RSA_PKCS1V15_SIGN) || defined(PSA_WANT_ALG_RSA_PSS)) && \ + (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) > PSA_SIGNATURE_MAX_SIZE) +#undef PSA_SIGNATURE_MAX_SIZE +#define PSA_SIGNATURE_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) +#endif + +/** 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 asymmetric encryption 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, + * 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)) : \ + 0u) + +/** A sufficient output buffer size for psa_asymmetric_encrypt(), for any + * supported asymmetric encryption. + * + * See also #PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg). + */ +/* This macro assumes that RSA is the only supported asymmetric encryption. */ +#define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_MAX_SIZE \ + (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS)) + +/** Sufficient output buffer size for psa_asymmetric_decrypt(). + * + * This macro returns a sufficient buffer size for a plaintext produced using + * a key of the specified type and size, with the specified algorithm. + * Note that the actual size of the plaintext 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 asymmetric encryption 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, + * 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) : \ + 0u) + +/** A sufficient output buffer size for psa_asymmetric_decrypt(), for any + * supported asymmetric decryption. + * + * This macro assumes that RSA is the only supported asymmetric encryption. + * + * See also #PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg). + */ +#define PSA_ASYMMETRIC_DECRYPT_OUTPUT_MAX_SIZE \ + (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS)) + +/* 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) / 8u + 5u) + +/* 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) + 11u) + +/* Maximum size of the export encoding of an RSA key pair. + * Assumes that the 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) \ + (9u * PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE((key_bits) / 2u + 1u) + 14u) + +/* 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-Params } -- 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) * 3u + 59u) + +/* 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) * 3u + 75u) + +/* 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) \ + (2u * PSA_BITS_TO_BYTES(key_bits) + 1u) + +/* 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)) + +/* Maximum size of the export encoding of an DH key pair. + * + * An DH key pair is represented by the secret value. + */ +#define PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(key_bits) \ + (PSA_BITS_TO_BYTES(key_bits)) + +/* Maximum size of the export encoding of an DH public key. + */ +#define PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_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 macro may evaluate 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_EXPORT_KEY_OUTPUT_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 + * + * \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_export_key() or psa_export_public_key() will not fail with + * #PSA_ERROR_BUFFER_TOO_SMALL. + * If the parameters are a valid combination that is not supported, + * return either a sensible size or 0. + * If the parameters are not valid, the return value is unspecified. + */ +#define PSA_EXPORT_KEY_OUTPUT_SIZE(key_type, key_bits) \ + (PSA_KEY_TYPE_IS_UNSTRUCTURED(key_type) ? PSA_BITS_TO_BYTES(key_bits) : \ + PSA_KEY_TYPE_IS_DH(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) : \ + 0u) + +/** Sufficient output buffer size for psa_export_public_key(). + * + * This macro returns a compile-time constant if its arguments are + * compile-time constants. + * + * \warning This macro may evaluate 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 public 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_EXPORT_PUBLIC_KEY_OUTPUT_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_public_key(key, buffer, buffer_size, &buffer_length); + * if (status != PSA_SUCCESS) handle_error(...); + * \endcode + * + * \param key_type A public key or key pair 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_export_public_key() will not fail with + * #PSA_ERROR_BUFFER_TOO_SMALL. + * If the parameters are a valid combination that is not + * supported, return either a sensible size or 0. + * If the parameters are not valid, + * the return value is unspecified. + * + * If the parameters are valid and supported, + * return the same result as + * #PSA_EXPORT_KEY_OUTPUT_SIZE( + * \p #PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR(\p key_type), + * \p key_bits). + */ +#define PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(key_type, key_bits) \ + (PSA_KEY_TYPE_IS_RSA(key_type) ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \ + PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \ + PSA_KEY_TYPE_IS_DH(key_type) ? PSA_BITS_TO_BYTES(key_bits) : \ + 0u) + +/** Sufficient buffer size for exporting any asymmetric key pair. + * + * This macro expands to a compile-time constant integer. This value is + * a sufficient buffer size when calling psa_export_key() to export any + * asymmetric key pair, regardless of the exact key type and key size. + * + * See also #PSA_EXPORT_KEY_OUTPUT_SIZE(\p key_type, \p key_bits). + */ +#define PSA_EXPORT_KEY_PAIR_MAX_SIZE 1 + +#if defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_BASIC) && \ + (PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) > \ + PSA_EXPORT_KEY_PAIR_MAX_SIZE) +#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE +#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \ + PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) +#endif +#if defined(PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_BASIC) && \ + (PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \ + PSA_EXPORT_KEY_PAIR_MAX_SIZE) +#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE +#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \ + PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) +#endif +#if defined(PSA_WANT_KEY_TYPE_DH_KEY_PAIR_BASIC) && \ + (PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) > \ + PSA_EXPORT_KEY_PAIR_MAX_SIZE) +#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE +#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \ + PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) +#endif + +/** Sufficient buffer size for exporting any asymmetric public key. + * + * This macro expands to a compile-time constant integer. This value is + * a sufficient buffer size when calling psa_export_key() or + * psa_export_public_key() to export any asymmetric public key, + * regardless of the exact key type and key size. + * + * See also #PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(\p key_type, \p key_bits). + */ +#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE 1 + +#if defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \ + (PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) > \ + PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) +#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE +#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \ + PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) +#endif +#if defined(PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY) && \ + (PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \ + PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) +#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE +#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \ + PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) +#endif +#if defined(PSA_WANT_KEY_TYPE_DH_PUBLIC_KEY) && \ + (PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) > \ + PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) +#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE +#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \ + PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) +#endif + +/** Sufficient output buffer size for psa_raw_key_agreement(). + * + * This macro returns a compile-time constant if its arguments are + * compile-time constants. + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE. + * + * \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_raw_key_agreement() will not fail with + * #PSA_ERROR_BUFFER_TOO_SMALL. + * If the parameters are a valid combination that + * is not supported, return either a sensible size or 0. + * If the parameters are not valid, + * the return value is unspecified. + */ +#define PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(key_type, key_bits) \ + ((PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) || \ + PSA_KEY_TYPE_IS_DH_KEY_PAIR(key_type)) ? PSA_BITS_TO_BYTES(key_bits) : 0u) + +/** Maximum size of the output from psa_raw_key_agreement(). + * + * This macro expands to a compile-time constant integer. This value is the + * maximum size of the output any raw key agreement algorithm, in bytes. + * + * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(\p key_type, \p key_bits). + */ +#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE 1 + +#if defined(PSA_WANT_ALG_ECDH) && \ + (PSA_BITS_TO_BYTES(PSA_VENDOR_ECC_MAX_CURVE_BITS) > PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE) +#undef PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE +#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_ECC_MAX_CURVE_BITS) +#endif +#if defined(PSA_WANT_ALG_FFDH) && \ + (PSA_BITS_TO_BYTES(PSA_VENDOR_FFDH_MAX_KEY_BITS) > PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE) +#undef PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE +#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_FFDH_MAX_KEY_BITS) +#endif + +/** The default IV size for a cipher algorithm, in bytes. + * + * The IV that is generated as part of a call to #psa_cipher_encrypt() is always + * the default IV length for the algorithm. + * + * This macro can be used to allocate a buffer of sufficient size to + * store the IV output from #psa_cipher_generate_iv() when using + * a multi-part cipher operation. + * + * See also #PSA_CIPHER_IV_MAX_SIZE. + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is compatible with algorithm \p alg. + * + * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that #PSA_ALG_IS_CIPHER(\p alg) is true). + * + * \return The default IV size for the specified key type and algorithm. + * If the algorithm does not use an IV, return 0. + * If the key type or cipher algorithm is not recognized, + * or the parameters are incompatible, return 0. + */ +#define PSA_CIPHER_IV_LENGTH(key_type, alg) \ + (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) > 1 && \ + ((alg) == PSA_ALG_CTR || \ + (alg) == PSA_ALG_CFB || \ + (alg) == PSA_ALG_OFB || \ + (alg) == PSA_ALG_XTS || \ + (alg) == PSA_ALG_CBC_NO_PADDING || \ + (alg) == PSA_ALG_CBC_PKCS7) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ + (key_type) == PSA_KEY_TYPE_CHACHA20 && \ + (alg) == PSA_ALG_STREAM_CIPHER ? 12u : \ + (alg) == PSA_ALG_CCM_STAR_NO_TAG ? 13u : \ + 0u) + +/** The maximum IV size for all supported cipher algorithms, in bytes. + * + * See also #PSA_CIPHER_IV_LENGTH(). + */ +#define PSA_CIPHER_IV_MAX_SIZE 16u + +/** The maximum size of the output of psa_cipher_encrypt(), in bytes. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_encrypt() will not fail due to an insufficient buffer size. + * Depending on the algorithm, the actual size of the output might be smaller. + * + * See also #PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(\p input_length). + * + * \warning This macro may evaluate its arguments multiple times or + * zero times, so you should not pass arguments that contain + * side effects. + * + * \param key_type A symmetric key type that is compatible with algorithm + * alg. + * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_CIPHER(\p alg) is true). + * \param input_length Size of the input in bytes. + * + * \return A sufficient output size for the specified key type and + * algorithm. If the key type or cipher algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(key_type, alg, input_length) \ + (alg == PSA_ALG_CBC_PKCS7 ? \ + (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) != 0 ? \ + PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \ + (input_length) + 1u) + \ + PSA_CIPHER_IV_LENGTH((key_type), (alg)) : 0u) : \ + (PSA_ALG_IS_CIPHER(alg) ? \ + (input_length) + PSA_CIPHER_IV_LENGTH((key_type), (alg)) : \ + 0u)) + +/** A sufficient output buffer size for psa_cipher_encrypt(), for any of the + * supported key types and cipher algorithms. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_encrypt() will not fail due to an insufficient buffer size. + * + * See also #PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). + * + * \param input_length Size of the input in bytes. + * + */ +#define PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(input_length) \ + (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, \ + (input_length) + 1u) + \ + PSA_CIPHER_IV_MAX_SIZE) + +/** The maximum size of the output of psa_cipher_decrypt(), in bytes. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_decrypt() will not fail due to an insufficient buffer size. + * Depending on the algorithm, the actual size of the output might be smaller. + * + * See also #PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(\p input_length). + * + * \param key_type A symmetric key type that is compatible with algorithm + * alg. + * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that + * #PSA_ALG_IS_CIPHER(\p alg) is true). + * \param input_length Size of the input in bytes. + * + * \return A sufficient output size for the specified key type and + * algorithm. If the key type or cipher algorithm is not + * recognized, or the parameters are incompatible, + * return 0. + */ +#define PSA_CIPHER_DECRYPT_OUTPUT_SIZE(key_type, alg, input_length) \ + (PSA_ALG_IS_CIPHER(alg) && \ + ((key_type) & PSA_KEY_TYPE_CATEGORY_MASK) == PSA_KEY_TYPE_CATEGORY_SYMMETRIC ? \ + (input_length) : \ + 0u) + +/** A sufficient output buffer size for psa_cipher_decrypt(), for any of the + * supported key types and cipher algorithms. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_decrypt() will not fail due to an insufficient buffer size. + * + * See also #PSA_CIPHER_DECRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). + * + * \param input_length Size of the input in bytes. + */ +#define PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(input_length) \ + (input_length) + +/** A sufficient output buffer size for psa_cipher_update(). + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_update() will not fail due to an insufficient buffer size. + * The actual size of the output might be smaller in any given call. + * + * See also #PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(\p input_length). + * + * \param key_type A symmetric key type that is compatible with algorithm + * alg. + * \param alg A cipher algorithm (PSA_ALG_XXX value such that + * #PSA_ALG_IS_CIPHER(\p alg) is true). + * \param input_length Size of the input in bytes. + * + * \return A sufficient output size for the specified key type and + * algorithm. If the key type or cipher algorithm is not + * recognized, or the parameters are incompatible, return 0. + */ +#define PSA_CIPHER_UPDATE_OUTPUT_SIZE(key_type, alg, input_length) \ + (PSA_ALG_IS_CIPHER(alg) ? \ + (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) != 0 ? \ + (((alg) == PSA_ALG_CBC_PKCS7 || \ + (alg) == PSA_ALG_CBC_NO_PADDING || \ + (alg) == PSA_ALG_ECB_NO_PADDING) ? \ + PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \ + input_length) : \ + (input_length)) : 0u) : \ + 0u) + +/** A sufficient output buffer size for psa_cipher_update(), for any of the + * supported key types and cipher algorithms. + * + * If the size of the output buffer is at least this large, it is guaranteed + * that psa_cipher_update() will not fail due to an insufficient buffer size. + * + * See also #PSA_CIPHER_UPDATE_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). + * + * \param input_length Size of the input in bytes. + */ +#define PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(input_length) \ + (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, input_length)) + +/** A sufficient ciphertext buffer size for psa_cipher_finish(). + * + * If the size of the ciphertext buffer is at least this large, it is + * guaranteed that psa_cipher_finish() will not fail due to an insufficient + * ciphertext buffer size. The actual size of the output might be smaller in + * any given call. + * + * See also #PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE(). + * + * \param key_type A symmetric key type that is compatible with algorithm + * alg. + * \param alg A cipher algorithm (PSA_ALG_XXX value such that + * #PSA_ALG_IS_CIPHER(\p alg) is true). + * \return A sufficient output size for the specified key type and + * algorithm. If the key type or cipher algorithm is not + * recognized, or the parameters are incompatible, return 0. + */ +#define PSA_CIPHER_FINISH_OUTPUT_SIZE(key_type, alg) \ + (PSA_ALG_IS_CIPHER(alg) ? \ + (alg == PSA_ALG_CBC_PKCS7 ? \ + PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ + 0u) : \ + 0u) + +/** A sufficient ciphertext buffer size for psa_cipher_finish(), for any of the + * supported key types and cipher algorithms. + * + * See also #PSA_CIPHER_FINISH_OUTPUT_SIZE(\p key_type, \p alg). + */ +#define PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE \ + (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) + +#endif /* PSA_CRYPTO_SIZES_H */ |