1 /** 2 * \file psa/crypto_sizes.h 3 * 4 * \brief PSA cryptography module: Mbed TLS buffer size macros 5 * 6 * \note This file may not be included directly. Applications must 7 * include psa/crypto.h. 8 * 9 * This file contains the definitions of macros that are useful to 10 * compute buffer sizes. The signatures and semantics of these macros 11 * are standardized, but the definitions are not, because they depend on 12 * the available algorithms and, in some cases, on permitted tolerances 13 * on buffer sizes. 14 * 15 * In implementations with isolation between the application and the 16 * cryptography module, implementers should take care to ensure that 17 * the definitions that are exposed to applications match what the 18 * module implements. 19 * 20 * Macros that compute sizes whose values do not depend on the 21 * implementation are in crypto.h. 22 */ 23 /* 24 * Copyright The Mbed TLS Contributors 25 * SPDX-License-Identifier: Apache-2.0 26 * 27 * Licensed under the Apache License, Version 2.0 (the "License"); you may 28 * not use this file except in compliance with the License. 29 * You may obtain a copy of the License at 30 * 31 * http://www.apache.org/licenses/LICENSE-2.0 32 * 33 * Unless required by applicable law or agreed to in writing, software 34 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT 35 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 36 * See the License for the specific language governing permissions and 37 * limitations under the License. 38 */ 39 40 #ifndef PSA_CRYPTO_SIZES_H 41 #define PSA_CRYPTO_SIZES_H 42 43 /* Include the Mbed TLS configuration file, the way Mbed TLS does it 44 * in each of its header files. */ 45 #if !defined(MBEDTLS_CONFIG_FILE) 46 #include "mbedtls/config.h" 47 #else 48 #include MBEDTLS_CONFIG_FILE 49 #endif 50 51 #define PSA_BITS_TO_BYTES(bits) (((bits) + 7) / 8) 52 #define PSA_BYTES_TO_BITS(bytes) ((bytes) * 8) 53 54 #define PSA_ROUND_UP_TO_MULTIPLE(block_size, length) \ 55 (((length) + (block_size) - 1) / (block_size) * (block_size)) 56 57 /** The size of the output of psa_hash_finish(), in bytes. 58 * 59 * This is also the hash size that psa_hash_verify() expects. 60 * 61 * \param alg A hash algorithm (\c PSA_ALG_XXX value such that 62 * #PSA_ALG_IS_HASH(\p alg) is true), or an HMAC algorithm 63 * (#PSA_ALG_HMAC(\c hash_alg) where \c hash_alg is a 64 * hash algorithm). 65 * 66 * \return The hash size for the specified hash algorithm. 67 * If the hash algorithm is not recognized, return 0. 68 */ 69 #define PSA_HASH_LENGTH(alg) \ 70 ( \ 71 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD2 ? 16 : \ 72 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD4 ? 16 : \ 73 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 16 : \ 74 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 20 : \ 75 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 20 : \ 76 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 28 : \ 77 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 32 : \ 78 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 48 : \ 79 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 64 : \ 80 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 28 : \ 81 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 32 : \ 82 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 28 : \ 83 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 32 : \ 84 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 48 : \ 85 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 64 : \ 86 0) 87 88 /** \def PSA_HASH_MAX_SIZE 89 * 90 * Maximum size of a hash. 91 * 92 * This macro expands to a compile-time constant integer. This value 93 * is the maximum size of a hash in bytes. 94 */ 95 /* Note: for HMAC-SHA-3, the block size is 144 bytes for HMAC-SHA3-226, 96 * 136 bytes for HMAC-SHA3-256, 104 bytes for SHA3-384, 72 bytes for 97 * HMAC-SHA3-512. */ 98 #if defined(MBEDTLS_SHA512_C) 99 #define PSA_HASH_MAX_SIZE 64 100 #define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128 101 #else 102 #define PSA_HASH_MAX_SIZE 32 103 #define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64 104 #endif 105 106 /** \def PSA_MAC_MAX_SIZE 107 * 108 * Maximum size of a MAC. 109 * 110 * This macro expands to a compile-time constant integer. This value 111 * is the maximum size of a MAC in bytes. 112 */ 113 /* All non-HMAC MACs have a maximum size that's smaller than the 114 * minimum possible value of PSA_HASH_MAX_SIZE in this implementation. */ 115 /* Note that the encoding of truncated MAC algorithms limits this value 116 * to 64 bytes. 117 */ 118 #define PSA_MAC_MAX_SIZE PSA_HASH_MAX_SIZE 119 120 /** The tag size for an AEAD algorithm, in bytes. 121 * 122 * \param alg An AEAD algorithm 123 * (\c PSA_ALG_XXX value such that 124 * #PSA_ALG_IS_AEAD(\p alg) is true). 125 * 126 * \return The tag size for the specified algorithm. 127 * If the AEAD algorithm does not have an identified 128 * tag that can be distinguished from the rest of 129 * the ciphertext, return 0. 130 * If the AEAD algorithm is not recognized, return 0. 131 */ 132 #define PSA_AEAD_TAG_LENGTH(alg) \ 133 (PSA_ALG_IS_AEAD(alg) ? \ 134 (((alg) & PSA_ALG_AEAD_TAG_LENGTH_MASK) >> PSA_AEAD_TAG_LENGTH_OFFSET) : \ 135 0) 136 137 /** The maximum tag size for all supported AEAD algorithms, in bytes. 138 * 139 * See also #PSA_AEAD_TAG_LENGTH(\p alg). 140 */ 141 #define PSA_AEAD_TAG_MAX_SIZE 16 142 143 /* The maximum size of an RSA key on this implementation, in bits. 144 * This is a vendor-specific macro. 145 * 146 * Mbed TLS does not set a hard limit on the size of RSA keys: any key 147 * whose parameters fit in a bignum is accepted. However large keys can 148 * induce a large memory usage and long computation times. Unlike other 149 * auxiliary macros in this file and in crypto.h, which reflect how the 150 * library is configured, this macro defines how the library is 151 * configured. This implementation refuses to import or generate an 152 * RSA key whose size is larger than the value defined here. 153 * 154 * Note that an implementation may set different size limits for different 155 * operations, and does not need to accept all key sizes up to the limit. */ 156 #define PSA_VENDOR_RSA_MAX_KEY_BITS 4096 157 158 /* The maximum size of an ECC key on this implementation, in bits. 159 * This is a vendor-specific macro. */ 160 #if defined(MBEDTLS_ECP_DP_SECP521R1_ENABLED) 161 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 521 162 #elif defined(MBEDTLS_ECP_DP_BP512R1_ENABLED) 163 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 512 164 #elif defined(MBEDTLS_ECP_DP_CURVE448_ENABLED) 165 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 448 166 #elif defined(MBEDTLS_ECP_DP_SECP384R1_ENABLED) 167 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 384 168 #elif defined(MBEDTLS_ECP_DP_BP384R1_ENABLED) 169 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 384 170 #elif defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) 171 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 256 172 #elif defined(MBEDTLS_ECP_DP_SECP256K1_ENABLED) 173 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 256 174 #elif defined(MBEDTLS_ECP_DP_BP256R1_ENABLED) 175 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 256 176 #elif defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) 177 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 255 178 #elif defined(MBEDTLS_ECP_DP_SECP224R1_ENABLED) 179 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 224 180 #elif defined(MBEDTLS_ECP_DP_SECP224K1_ENABLED) 181 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 224 182 #elif defined(MBEDTLS_ECP_DP_SECP192R1_ENABLED) 183 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 192 184 #elif defined(MBEDTLS_ECP_DP_SECP192K1_ENABLED) 185 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 192 186 #else 187 #define PSA_VENDOR_ECC_MAX_CURVE_BITS 0 188 #endif 189 190 /** This macro returns the maximum supported length of the PSK for the 191 * TLS-1.2 PSK-to-MS key derivation 192 * (#PSA_ALG_TLS12_PSK_TO_MS(\p hash_alg)). 193 * 194 * The maximum supported length does not depend on the chosen hash algorithm. 195 * 196 * Quoting RFC 4279, Sect 5.3: 197 * TLS implementations supporting these ciphersuites MUST support 198 * arbitrary PSK identities up to 128 octets in length, and arbitrary 199 * PSKs up to 64 octets in length. Supporting longer identities and 200 * keys is RECOMMENDED. 201 * 202 * Therefore, no implementation should define a value smaller than 64 203 * for #PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE. 204 */ 205 #define PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE 128 206 207 /** The maximum size of a block cipher. */ 208 #define PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE 16 209 210 /** The size of the output of psa_mac_sign_finish(), in bytes. 211 * 212 * This is also the MAC size that psa_mac_verify_finish() expects. 213 * 214 * \warning This macro may evaluate its arguments multiple times or 215 * zero times, so you should not pass arguments that contain 216 * side effects. 217 * 218 * \param key_type The type of the MAC key. 219 * \param key_bits The size of the MAC key in bits. 220 * \param alg A MAC algorithm (\c PSA_ALG_XXX value such that 221 * #PSA_ALG_IS_MAC(\p alg) is true). 222 * 223 * \return The MAC size for the specified algorithm with 224 * the specified key parameters. 225 * \return 0 if the MAC algorithm is not recognized. 226 * \return Either 0 or the correct size for a MAC algorithm that 227 * the implementation recognizes, but does not support. 228 * \return Unspecified if the key parameters are not consistent 229 * with the algorithm. 230 */ 231 #define PSA_MAC_LENGTH(key_type, key_bits, alg) \ 232 ((alg) & PSA_ALG_MAC_TRUNCATION_MASK ? PSA_MAC_TRUNCATED_LENGTH(alg) : \ 233 PSA_ALG_IS_HMAC(alg) ? PSA_HASH_LENGTH(PSA_ALG_HMAC_GET_HASH(alg)) : \ 234 PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ 235 ((void)(key_type), (void)(key_bits), 0)) 236 237 /** The maximum size of the output of psa_aead_encrypt(), in bytes. 238 * 239 * If the size of the ciphertext buffer is at least this large, it is 240 * guaranteed that psa_aead_encrypt() will not fail due to an 241 * insufficient buffer size. Depending on the algorithm, the actual size of 242 * the ciphertext may be smaller. 243 * 244 * \warning This macro may evaluate its arguments multiple times or 245 * zero times, so you should not pass arguments that contain 246 * side effects. 247 * 248 * \param alg An AEAD algorithm 249 * (\c PSA_ALG_XXX value such that 250 * #PSA_ALG_IS_AEAD(\p alg) is true). 251 * \param plaintext_length Size of the plaintext in bytes. 252 * 253 * \return The AEAD ciphertext size for the specified 254 * algorithm. 255 * If the AEAD algorithm is not recognized, return 0. 256 */ 257 #define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(alg, plaintext_length) \ 258 (PSA_AEAD_TAG_LENGTH(alg) != 0 ? \ 259 (plaintext_length) + PSA_AEAD_TAG_LENGTH(alg) : \ 260 0) 261 262 /** A sufficient output buffer size for psa_aead_encrypt(), for any of the 263 * supported key types and AEAD algorithms. 264 * 265 * If the size of the ciphertext buffer is at least this large, it is guaranteed 266 * that psa_aead_encrypt() will not fail due to an insufficient buffer size. 267 * 268 * \note This macro returns a compile-time constant if its arguments are 269 * compile-time constants. 270 * 271 * See also #PSA_AEAD_ENCRYPT_OUTPUT_SIZE(\p alg, \p plaintext_length). 272 * 273 * \param plaintext_length Size of the plaintext in bytes. 274 * 275 * \return A sufficient output buffer size for any of the 276 * supported key types and AEAD algorithms. 277 * 278 */ 279 #define PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(plaintext_length) \ 280 ((plaintext_length) + PSA_AEAD_TAG_MAX_SIZE) 281 282 283 /** The maximum size of the output of psa_aead_decrypt(), in bytes. 284 * 285 * If the size of the plaintext buffer is at least this large, it is 286 * guaranteed that psa_aead_decrypt() will not fail due to an 287 * insufficient buffer size. Depending on the algorithm, the actual size of 288 * the plaintext may be smaller. 289 * 290 * \warning This macro may evaluate its arguments multiple times or 291 * zero times, so you should not pass arguments that contain 292 * side effects. 293 * 294 * \param alg An AEAD algorithm 295 * (\c PSA_ALG_XXX value such that 296 * #PSA_ALG_IS_AEAD(\p alg) is true). 297 * \param ciphertext_length Size of the plaintext in bytes. 298 * 299 * \return The AEAD ciphertext size for the specified 300 * algorithm. 301 * If the AEAD algorithm is not recognized, return 0. 302 */ 303 #define PSA_AEAD_DECRYPT_OUTPUT_SIZE(alg, ciphertext_length) \ 304 (PSA_AEAD_TAG_LENGTH(alg) != 0 ? \ 305 (ciphertext_length) - PSA_AEAD_TAG_LENGTH(alg) : \ 306 0) 307 308 /** A sufficient output buffer size for psa_aead_decrypt(), for any of the 309 * supported key types and AEAD algorithms. 310 * 311 * If the size of the plaintext buffer is at least this large, it is guaranteed 312 * that psa_aead_decrypt() will not fail due to an insufficient buffer size. 313 * 314 * \note This macro returns a compile-time constant if its arguments are 315 * compile-time constants. 316 * 317 * See also #PSA_AEAD_DECRYPT_OUTPUT_SIZE(\p alg, \p ciphertext_length). 318 * 319 * \param ciphertext_length Size of the ciphertext in bytes. 320 * 321 * \return A sufficient output buffer size for any of the 322 * supported key types and AEAD algorithms. 323 * 324 */ 325 #define PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(ciphertext_length) \ 326 (ciphertext_length) 327 328 /** The default nonce size for an AEAD algorithm, in bytes. 329 * 330 * This macro can be used to allocate a buffer of sufficient size to 331 * store the nonce output from #psa_aead_generate_nonce(). 332 * 333 * See also #PSA_AEAD_NONCE_MAX_SIZE. 334 * 335 * \note This is not the maximum size of nonce supported as input to 336 * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(), 337 * just the default size that is generated by #psa_aead_generate_nonce(). 338 * 339 * \warning This macro may evaluate its arguments multiple times or 340 * zero times, so you should not pass arguments that contain 341 * side effects. 342 * 343 * \param key_type A symmetric key type that is compatible with 344 * algorithm \p alg. 345 * 346 * \param alg An AEAD algorithm (\c PSA_ALG_XXX value such that 347 * #PSA_ALG_IS_AEAD(\p alg) is true). 348 * 349 * \return The default nonce size for the specified key type and algorithm. 350 * If the key type or AEAD algorithm is not recognized, 351 * or the parameters are incompatible, return 0. 352 */ 353 #define PSA_AEAD_NONCE_LENGTH(key_type, alg) \ 354 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) == 16 && \ 355 (PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG(alg) == PSA_ALG_CCM || \ 356 PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG(alg) == PSA_ALG_GCM) ? 12 : \ 357 (key_type) == PSA_KEY_TYPE_CHACHA20 && \ 358 PSA_ALG_AEAD_WITH_DEFAULT_LENGTH_TAG(alg) == PSA_ALG_CHACHA20_POLY1305 ? 12 : \ 359 0) 360 361 /** The maximum default nonce size among all supported pairs of key types and 362 * AEAD algorithms, in bytes. 363 * 364 * This is equal to or greater than any value that #PSA_AEAD_NONCE_LENGTH() 365 * may return. 366 * 367 * \note This is not the maximum size of nonce supported as input to 368 * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(), 369 * just the largest size that may be generated by 370 * #psa_aead_generate_nonce(). 371 */ 372 #define PSA_AEAD_NONCE_MAX_SIZE 12 373 374 /** A sufficient output buffer size for psa_aead_update(). 375 * 376 * If the size of the output buffer is at least this large, it is 377 * guaranteed that psa_aead_update() will not fail due to an 378 * insufficient buffer size. The actual size of the output may be smaller 379 * in any given call. 380 * 381 * \warning This macro may evaluate its arguments multiple times or 382 * zero times, so you should not pass arguments that contain 383 * side effects. 384 * 385 * \param alg An AEAD algorithm 386 * (\c PSA_ALG_XXX value such that 387 * #PSA_ALG_IS_AEAD(\p alg) is true). 388 * \param input_length Size of the input in bytes. 389 * 390 * \return A sufficient output buffer size for the specified 391 * algorithm. 392 * If the AEAD algorithm is not recognized, return 0. 393 */ 394 /* For all the AEAD modes defined in this specification, it is possible 395 * to emit output without delay. However, hardware may not always be 396 * capable of this. So for modes based on a block cipher, allow the 397 * implementation to delay the output until it has a full block. */ 398 #define PSA_AEAD_UPDATE_OUTPUT_SIZE(alg, input_length) \ 399 (PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ 400 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, (input_length)) : \ 401 (input_length)) 402 403 /** A sufficient output buffer size for psa_aead_update(), for any of the 404 * supported key types and AEAD algorithms. 405 * 406 * If the size of the output buffer is at least this large, it is guaranteed 407 * that psa_aead_update() will not fail due to an insufficient buffer size. 408 * 409 * See also #PSA_AEAD_UPDATE_OUTPUT_SIZE(\p alg, \p input_length). 410 * 411 * \param input_length Size of the input in bytes. 412 */ 413 #define PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(input_length) \ 414 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, (input_length))) 415 416 /** A sufficient ciphertext buffer size for psa_aead_finish(). 417 * 418 * If the size of the ciphertext buffer is at least this large, it is 419 * guaranteed that psa_aead_finish() will not fail due to an 420 * insufficient ciphertext buffer size. The actual size of the output may 421 * be smaller in any given call. 422 * 423 * \param alg An AEAD algorithm 424 * (\c PSA_ALG_XXX value such that 425 * #PSA_ALG_IS_AEAD(\p alg) is true). 426 * 427 * \return A sufficient ciphertext buffer size for the 428 * specified algorithm. 429 * If the AEAD algorithm is not recognized, return 0. 430 */ 431 #define PSA_AEAD_FINISH_OUTPUT_SIZE(alg) \ 432 (PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ 433 PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE : \ 434 0) 435 436 /** A sufficient ciphertext buffer size for psa_aead_finish(), for any of the 437 * supported key types and AEAD algorithms. 438 * 439 * See also #PSA_AEAD_FINISH_OUTPUT_SIZE(\p alg). 440 */ 441 #define PSA_AEAD_FINISH_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) 442 443 /** A sufficient plaintext buffer size for psa_aead_verify(). 444 * 445 * If the size of the plaintext buffer is at least this large, it is 446 * guaranteed that psa_aead_verify() will not fail due to an 447 * insufficient plaintext buffer size. The actual size of the output may 448 * be smaller in any given call. 449 * 450 * \param alg An AEAD algorithm 451 * (\c PSA_ALG_XXX value such that 452 * #PSA_ALG_IS_AEAD(\p alg) is true). 453 * 454 * \return A sufficient plaintext buffer size for the 455 * specified algorithm. 456 * If the AEAD algorithm is not recognized, return 0. 457 */ 458 #define PSA_AEAD_VERIFY_OUTPUT_SIZE(alg) \ 459 (PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \ 460 PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE : \ 461 0) 462 463 /** A sufficient plaintext buffer size for psa_aead_verify(), for any of the 464 * supported key types and AEAD algorithms. 465 * 466 * See also #PSA_AEAD_VERIFY_OUTPUT_SIZE(\p alg). 467 */ 468 #define PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) 469 470 #define PSA_RSA_MINIMUM_PADDING_SIZE(alg) \ 471 (PSA_ALG_IS_RSA_OAEP(alg) ? \ 472 2 * PSA_HASH_LENGTH(PSA_ALG_RSA_OAEP_GET_HASH(alg)) + 1 : \ 473 11 /*PKCS#1v1.5*/) 474 475 /** 476 * \brief ECDSA signature size for a given curve bit size 477 * 478 * \param curve_bits Curve size in bits. 479 * \return Signature size in bytes. 480 * 481 * \note This macro returns a compile-time constant if its argument is one. 482 */ 483 #define PSA_ECDSA_SIGNATURE_SIZE(curve_bits) \ 484 (PSA_BITS_TO_BYTES(curve_bits) * 2) 485 486 /** Sufficient signature buffer size for psa_sign_hash(). 487 * 488 * This macro returns a sufficient buffer size for a signature using a key 489 * of the specified type and size, with the specified algorithm. 490 * Note that the actual size of the signature may be smaller 491 * (some algorithms produce a variable-size signature). 492 * 493 * \warning This function may call its arguments multiple times or 494 * zero times, so you should not pass arguments that contain 495 * side effects. 496 * 497 * \param key_type An asymmetric key type (this may indifferently be a 498 * key pair type or a public key type). 499 * \param key_bits The size of the key in bits. 500 * \param alg The signature algorithm. 501 * 502 * \return If the parameters are valid and supported, return 503 * a buffer size in bytes that guarantees that 504 * psa_sign_hash() will not fail with 505 * #PSA_ERROR_BUFFER_TOO_SMALL. 506 * If the parameters are a valid combination that is not supported, 507 * return either a sensible size or 0. 508 * If the parameters are not valid, the 509 * return value is unspecified. 510 */ 511 #define PSA_SIGN_OUTPUT_SIZE(key_type, key_bits, alg) \ 512 (PSA_KEY_TYPE_IS_RSA(key_type) ? ((void)alg, PSA_BITS_TO_BYTES(key_bits)) : \ 513 PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_ECDSA_SIGNATURE_SIZE(key_bits) : \ 514 ((void)alg, 0)) 515 516 #define PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE \ 517 PSA_ECDSA_SIGNATURE_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) 518 519 /** \def PSA_SIGNATURE_MAX_SIZE 520 * 521 * Maximum size of an asymmetric signature. 522 * 523 * This macro expands to a compile-time constant integer. This value 524 * is the maximum size of a signature in bytes. 525 */ 526 #define PSA_SIGNATURE_MAX_SIZE \ 527 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) > PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE ? \ 528 PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) : \ 529 PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE) 530 531 /** Sufficient output buffer size for psa_asymmetric_encrypt(). 532 * 533 * This macro returns a sufficient buffer size for a ciphertext produced using 534 * a key of the specified type and size, with the specified algorithm. 535 * Note that the actual size of the ciphertext may be smaller, depending 536 * on the algorithm. 537 * 538 * \warning This function may call its arguments multiple times or 539 * zero times, so you should not pass arguments that contain 540 * side effects. 541 * 542 * \param key_type An asymmetric key type (this may indifferently be a 543 * key pair type or a public key type). 544 * \param key_bits The size of the key in bits. 545 * \param alg The asymmetric encryption algorithm. 546 * 547 * \return If the parameters are valid and supported, return 548 * a buffer size in bytes that guarantees that 549 * psa_asymmetric_encrypt() will not fail with 550 * #PSA_ERROR_BUFFER_TOO_SMALL. 551 * If the parameters are a valid combination that is not supported, 552 * return either a sensible size or 0. 553 * If the parameters are not valid, the 554 * return value is unspecified. 555 */ 556 #define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \ 557 (PSA_KEY_TYPE_IS_RSA(key_type) ? \ 558 ((void)alg, PSA_BITS_TO_BYTES(key_bits)) : \ 559 0) 560 561 /** A sufficient output buffer size for psa_asymmetric_encrypt(), for any 562 * supported asymmetric encryption. 563 * 564 * See also #PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg). 565 */ 566 /* This macro assumes that RSA is the only supported asymmetric encryption. */ 567 #define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_MAX_SIZE \ 568 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS)) 569 570 /** Sufficient output buffer size for psa_asymmetric_decrypt(). 571 * 572 * This macro returns a sufficient buffer size for a plaintext produced using 573 * a key of the specified type and size, with the specified algorithm. 574 * Note that the actual size of the plaintext may be smaller, depending 575 * on the algorithm. 576 * 577 * \warning This function may call its arguments multiple times or 578 * zero times, so you should not pass arguments that contain 579 * side effects. 580 * 581 * \param key_type An asymmetric key type (this may indifferently be a 582 * key pair type or a public key type). 583 * \param key_bits The size of the key in bits. 584 * \param alg The asymmetric encryption algorithm. 585 * 586 * \return If the parameters are valid and supported, return 587 * a buffer size in bytes that guarantees that 588 * psa_asymmetric_decrypt() will not fail with 589 * #PSA_ERROR_BUFFER_TOO_SMALL. 590 * If the parameters are a valid combination that is not supported, 591 * return either a sensible size or 0. 592 * If the parameters are not valid, the 593 * return value is unspecified. 594 */ 595 #define PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \ 596 (PSA_KEY_TYPE_IS_RSA(key_type) ? \ 597 PSA_BITS_TO_BYTES(key_bits) - PSA_RSA_MINIMUM_PADDING_SIZE(alg) : \ 598 0) 599 600 /** A sufficient output buffer size for psa_asymmetric_decrypt(), for any 601 * supported asymmetric decryption. 602 * 603 * This macro assumes that RSA is the only supported asymmetric encryption. 604 * 605 * See also #PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg). 606 */ 607 #define PSA_ASYMMETRIC_DECRYPT_OUTPUT_MAX_SIZE \ 608 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS)) 609 610 /* Maximum size of the ASN.1 encoding of an INTEGER with the specified 611 * number of bits. 612 * 613 * This definition assumes that bits <= 2^19 - 9 so that the length field 614 * is at most 3 bytes. The length of the encoding is the length of the 615 * bit string padded to a whole number of bytes plus: 616 * - 1 type byte; 617 * - 1 to 3 length bytes; 618 * - 0 to 1 bytes of leading 0 due to the sign bit. 619 */ 620 #define PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(bits) \ 621 ((bits) / 8 + 5) 622 623 /* Maximum size of the export encoding of an RSA public key. 624 * Assumes that the public exponent is less than 2^32. 625 * 626 * RSAPublicKey ::= SEQUENCE { 627 * modulus INTEGER, -- n 628 * publicExponent INTEGER } -- e 629 * 630 * - 4 bytes of SEQUENCE overhead; 631 * - n : INTEGER; 632 * - 7 bytes for the public exponent. 633 */ 634 #define PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) \ 635 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) + 11) 636 637 /* Maximum size of the export encoding of an RSA key pair. 638 * Assumes thatthe public exponent is less than 2^32 and that the size 639 * difference between the two primes is at most 1 bit. 640 * 641 * RSAPrivateKey ::= SEQUENCE { 642 * version Version, -- 0 643 * modulus INTEGER, -- N-bit 644 * publicExponent INTEGER, -- 32-bit 645 * privateExponent INTEGER, -- N-bit 646 * prime1 INTEGER, -- N/2-bit 647 * prime2 INTEGER, -- N/2-bit 648 * exponent1 INTEGER, -- N/2-bit 649 * exponent2 INTEGER, -- N/2-bit 650 * coefficient INTEGER, -- N/2-bit 651 * } 652 * 653 * - 4 bytes of SEQUENCE overhead; 654 * - 3 bytes of version; 655 * - 7 half-size INTEGERs plus 2 full-size INTEGERs, 656 * overapproximated as 9 half-size INTEGERS; 657 * - 7 bytes for the public exponent. 658 */ 659 #define PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) \ 660 (9 * PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE((key_bits) / 2 + 1) + 14) 661 662 /* Maximum size of the export encoding of a DSA public key. 663 * 664 * SubjectPublicKeyInfo ::= SEQUENCE { 665 * algorithm AlgorithmIdentifier, 666 * subjectPublicKey BIT STRING } -- contains DSAPublicKey 667 * AlgorithmIdentifier ::= SEQUENCE { 668 * algorithm OBJECT IDENTIFIER, 669 * parameters Dss-Parms } -- SEQUENCE of 3 INTEGERs 670 * DSAPublicKey ::= INTEGER -- public key, Y 671 * 672 * - 3 * 4 bytes of SEQUENCE overhead; 673 * - 1 + 1 + 7 bytes of algorithm (DSA OID); 674 * - 4 bytes of BIT STRING overhead; 675 * - 3 full-size INTEGERs (p, g, y); 676 * - 1 + 1 + 32 bytes for 1 sub-size INTEGER (q <= 256 bits). 677 */ 678 #define PSA_KEY_EXPORT_DSA_PUBLIC_KEY_MAX_SIZE(key_bits) \ 679 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3 + 59) 680 681 /* Maximum size of the export encoding of a DSA key pair. 682 * 683 * DSAPrivateKey ::= SEQUENCE { 684 * version Version, -- 0 685 * prime INTEGER, -- p 686 * subprime INTEGER, -- q 687 * generator INTEGER, -- g 688 * public INTEGER, -- y 689 * private INTEGER, -- x 690 * } 691 * 692 * - 4 bytes of SEQUENCE overhead; 693 * - 3 bytes of version; 694 * - 3 full-size INTEGERs (p, g, y); 695 * - 2 * (1 + 1 + 32) bytes for 2 sub-size INTEGERs (q, x <= 256 bits). 696 */ 697 #define PSA_KEY_EXPORT_DSA_KEY_PAIR_MAX_SIZE(key_bits) \ 698 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3 + 75) 699 700 /* Maximum size of the export encoding of an ECC public key. 701 * 702 * The representation of an ECC public key is: 703 * - The byte 0x04; 704 * - `x_P` as a `ceiling(m/8)`-byte string, big-endian; 705 * - `y_P` as a `ceiling(m/8)`-byte string, big-endian; 706 * - where m is the bit size associated with the curve. 707 * 708 * - 1 byte + 2 * point size. 709 */ 710 #define PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) \ 711 (2 * PSA_BITS_TO_BYTES(key_bits) + 1) 712 713 /* Maximum size of the export encoding of an ECC key pair. 714 * 715 * An ECC key pair is represented by the secret value. 716 */ 717 #define PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) \ 718 (PSA_BITS_TO_BYTES(key_bits)) 719 720 /** Sufficient output buffer size for psa_export_key() or 721 * psa_export_public_key(). 722 * 723 * This macro returns a compile-time constant if its arguments are 724 * compile-time constants. 725 * 726 * \warning This macro may evaluate its arguments multiple times or 727 * zero times, so you should not pass arguments that contain 728 * side effects. 729 * 730 * The following code illustrates how to allocate enough memory to export 731 * a key by querying the key type and size at runtime. 732 * \code{c} 733 * psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT; 734 * psa_status_t status; 735 * status = psa_get_key_attributes(key, &attributes); 736 * if (status != PSA_SUCCESS) handle_error(...); 737 * psa_key_type_t key_type = psa_get_key_type(&attributes); 738 * size_t key_bits = psa_get_key_bits(&attributes); 739 * size_t buffer_size = PSA_EXPORT_KEY_OUTPUT_SIZE(key_type, key_bits); 740 * psa_reset_key_attributes(&attributes); 741 * uint8_t *buffer = malloc(buffer_size); 742 * if (buffer == NULL) handle_error(...); 743 * size_t buffer_length; 744 * status = psa_export_key(key, buffer, buffer_size, &buffer_length); 745 * if (status != PSA_SUCCESS) handle_error(...); 746 * \endcode 747 * 748 * \param key_type A supported key type. 749 * \param key_bits The size of the key in bits. 750 * 751 * \return If the parameters are valid and supported, return 752 * a buffer size in bytes that guarantees that 753 * psa_export_key() or psa_export_public_key() will not fail with 754 * #PSA_ERROR_BUFFER_TOO_SMALL. 755 * If the parameters are a valid combination that is not supported, 756 * return either a sensible size or 0. 757 * If the parameters are not valid, the return value is unspecified. 758 */ 759 #define PSA_EXPORT_KEY_OUTPUT_SIZE(key_type, key_bits) \ 760 (PSA_KEY_TYPE_IS_UNSTRUCTURED(key_type) ? PSA_BITS_TO_BYTES(key_bits) : \ 761 (key_type) == PSA_KEY_TYPE_RSA_KEY_PAIR ? PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) : \ 762 (key_type) == PSA_KEY_TYPE_RSA_PUBLIC_KEY ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \ 763 (key_type) == PSA_KEY_TYPE_DSA_KEY_PAIR ? PSA_KEY_EXPORT_DSA_KEY_PAIR_MAX_SIZE(key_bits) : \ 764 (key_type) == PSA_KEY_TYPE_DSA_PUBLIC_KEY ? PSA_KEY_EXPORT_DSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \ 765 PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) ? PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) : \ 766 PSA_KEY_TYPE_IS_ECC_PUBLIC_KEY(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \ 767 0) 768 769 /** Sufficient output buffer size for psa_export_public_key(). 770 * 771 * This macro returns a compile-time constant if its arguments are 772 * compile-time constants. 773 * 774 * \warning This macro may evaluate its arguments multiple times or 775 * zero times, so you should not pass arguments that contain 776 * side effects. 777 * 778 * The following code illustrates how to allocate enough memory to export 779 * a public key by querying the key type and size at runtime. 780 * \code{c} 781 * psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT; 782 * psa_status_t status; 783 * status = psa_get_key_attributes(key, &attributes); 784 * if (status != PSA_SUCCESS) handle_error(...); 785 * psa_key_type_t key_type = psa_get_key_type(&attributes); 786 * size_t key_bits = psa_get_key_bits(&attributes); 787 * size_t buffer_size = PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(key_type, key_bits); 788 * psa_reset_key_attributes(&attributes); 789 * uint8_t *buffer = malloc(buffer_size); 790 * if (buffer == NULL) handle_error(...); 791 * size_t buffer_length; 792 * status = psa_export_public_key(key, buffer, buffer_size, &buffer_length); 793 * if (status != PSA_SUCCESS) handle_error(...); 794 * \endcode 795 * 796 * \param key_type A public key or key pair key type. 797 * \param key_bits The size of the key in bits. 798 * 799 * \return If the parameters are valid and supported, return 800 * a buffer size in bytes that guarantees that 801 * psa_export_public_key() will not fail with 802 * #PSA_ERROR_BUFFER_TOO_SMALL. 803 * If the parameters are a valid combination that is not 804 * supported, return either a sensible size or 0. 805 * If the parameters are not valid, 806 * the return value is unspecified. 807 * 808 * If the parameters are valid and supported, 809 * return the same result as 810 * #PSA_EXPORT_KEY_OUTPUT_SIZE( 811 * \p #PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR(\p key_type), 812 * \p key_bits). 813 */ 814 #define PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(key_type, key_bits) \ 815 (PSA_KEY_TYPE_IS_RSA(key_type) ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \ 816 PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \ 817 0) 818 819 /** Sufficient buffer size for exporting any asymmetric key pair. 820 * 821 * This macro expands to a compile-time constant integer. This value is 822 * a sufficient buffer size when calling psa_export_key() to export any 823 * asymmetric key pair, regardless of the exact key type and key size. 824 * 825 * See also #PSA_EXPORT_KEY_OUTPUT_SIZE(\p key_type, \p key_bits). 826 */ 827 #define PSA_EXPORT_KEY_PAIR_MAX_SIZE \ 828 (PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \ 829 PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) ? \ 830 PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) : \ 831 PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)) 832 833 /** Sufficient buffer size for exporting any asymmetric public key. 834 * 835 * This macro expands to a compile-time constant integer. This value is 836 * a sufficient buffer size when calling psa_export_key() or 837 * psa_export_public_key() to export any asymmetric public key, 838 * regardless of the exact key type and key size. 839 * 840 * See also #PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(\p key_type, \p key_bits). 841 */ 842 #define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \ 843 (PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \ 844 PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) ? \ 845 PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) : \ 846 PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)) 847 848 /** Sufficient output buffer size for psa_raw_key_agreement(). 849 * 850 * This macro returns a compile-time constant if its arguments are 851 * compile-time constants. 852 * 853 * \warning This macro may evaluate its arguments multiple times or 854 * zero times, so you should not pass arguments that contain 855 * side effects. 856 * 857 * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE. 858 * 859 * \param key_type A supported key type. 860 * \param key_bits The size of the key in bits. 861 * 862 * \return If the parameters are valid and supported, return 863 * a buffer size in bytes that guarantees that 864 * psa_raw_key_agreement() will not fail with 865 * #PSA_ERROR_BUFFER_TOO_SMALL. 866 * If the parameters are a valid combination that 867 * is not supported, return either a sensible size or 0. 868 * If the parameters are not valid, 869 * the return value is unspecified. 870 */ 871 /* FFDH is not yet supported in PSA. */ 872 #define PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(key_type, key_bits) \ 873 (PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) ? \ 874 PSA_BITS_TO_BYTES(key_bits) : \ 875 0) 876 877 /** Maximum size of the output from psa_raw_key_agreement(). 878 * 879 * This macro expands to a compile-time constant integer. This value is the 880 * maximum size of the output any raw key agreement algorithm, in bytes. 881 * 882 * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(\p key_type, \p key_bits). 883 */ 884 #define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE \ 885 (PSA_BITS_TO_BYTES(PSA_VENDOR_ECC_MAX_CURVE_BITS)) 886 887 /** The default IV size for a cipher algorithm, in bytes. 888 * 889 * The IV that is generated as part of a call to #psa_cipher_encrypt() is always 890 * the default IV length for the algorithm. 891 * 892 * This macro can be used to allocate a buffer of sufficient size to 893 * store the IV output from #psa_cipher_generate_iv() when using 894 * a multi-part cipher operation. 895 * 896 * See also #PSA_CIPHER_IV_MAX_SIZE. 897 * 898 * \warning This macro may evaluate its arguments multiple times or 899 * zero times, so you should not pass arguments that contain 900 * side effects. 901 * 902 * \param key_type A symmetric key type that is compatible with algorithm \p alg. 903 * 904 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that #PSA_ALG_IS_CIPHER(\p alg) is true). 905 * 906 * \return The default IV size for the specified key type and algorithm. 907 * If the algorithm does not use an IV, return 0. 908 * If the key type or cipher algorithm is not recognized, 909 * or the parameters are incompatible, return 0. 910 */ 911 #define PSA_CIPHER_IV_LENGTH(key_type, alg) \ 912 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) > 1 && \ 913 ((alg) == PSA_ALG_CTR || \ 914 (alg) == PSA_ALG_CFB || \ 915 (alg) == PSA_ALG_OFB || \ 916 (alg) == PSA_ALG_XTS || \ 917 (alg) == PSA_ALG_CBC_NO_PADDING || \ 918 (alg) == PSA_ALG_CBC_PKCS7) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ 919 (key_type) == PSA_KEY_TYPE_CHACHA20 && \ 920 (alg) == PSA_ALG_STREAM_CIPHER ? 12 : \ 921 0) 922 923 /** The maximum IV size for all supported cipher algorithms, in bytes. 924 * 925 * See also #PSA_CIPHER_IV_LENGTH(). 926 */ 927 #define PSA_CIPHER_IV_MAX_SIZE 16 928 929 /** The maximum size of the output of psa_cipher_encrypt(), in bytes. 930 * 931 * If the size of the output buffer is at least this large, it is guaranteed 932 * that psa_cipher_encrypt() will not fail due to an insufficient buffer size. 933 * Depending on the algorithm, the actual size of the output might be smaller. 934 * 935 * See also #PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(\p input_length). 936 * 937 * \warning This macro may evaluate its arguments multiple times or 938 * zero times, so you should not pass arguments that contain 939 * side effects. 940 * 941 * \param key_type A symmetric key type that is compatible with algorithm 942 * alg. 943 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that 944 * #PSA_ALG_IS_CIPHER(\p alg) is true). 945 * \param input_length Size of the input in bytes. 946 * 947 * \return A sufficient output size for the specified key type and 948 * algorithm. If the key type or cipher algorithm is not 949 * recognized, or the parameters are incompatible, 950 * return 0. 951 */ 952 #define PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(key_type, alg, input_length) \ 953 (alg == PSA_ALG_CBC_PKCS7 ? \ 954 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \ 955 (input_length) + 1) + \ 956 PSA_CIPHER_IV_LENGTH((key_type), (alg)) : \ 957 (PSA_ALG_IS_CIPHER(alg) ? \ 958 (input_length) + PSA_CIPHER_IV_LENGTH((key_type), (alg)) : \ 959 0)) 960 961 /** A sufficient output buffer size for psa_cipher_encrypt(), for any of the 962 * supported key types and cipher algorithms. 963 * 964 * If the size of the output buffer is at least this large, it is guaranteed 965 * that psa_cipher_encrypt() will not fail due to an insufficient buffer size. 966 * 967 * See also #PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). 968 * 969 * \param input_length Size of the input in bytes. 970 * 971 */ 972 #define PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(input_length) \ 973 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, \ 974 (input_length) + 1) + \ 975 PSA_CIPHER_IV_MAX_SIZE) 976 977 /** The maximum size of the output of psa_cipher_decrypt(), in bytes. 978 * 979 * If the size of the output buffer is at least this large, it is guaranteed 980 * that psa_cipher_decrypt() will not fail due to an insufficient buffer size. 981 * Depending on the algorithm, the actual size of the output might be smaller. 982 * 983 * See also #PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(\p input_length). 984 * 985 * \param key_type A symmetric key type that is compatible with algorithm 986 * alg. 987 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that 988 * #PSA_ALG_IS_CIPHER(\p alg) is true). 989 * \param input_length Size of the input in bytes. 990 * 991 * \return A sufficient output size for the specified key type and 992 * algorithm. If the key type or cipher algorithm is not 993 * recognized, or the parameters are incompatible, 994 * return 0. 995 */ 996 #define PSA_CIPHER_DECRYPT_OUTPUT_SIZE(key_type, alg, input_length) \ 997 (PSA_ALG_IS_CIPHER(alg) && \ 998 ((key_type) & PSA_KEY_TYPE_CATEGORY_MASK) == PSA_KEY_TYPE_CATEGORY_SYMMETRIC ? \ 999 (input_length) : \ 1000 0) 1001 1002 /** A sufficient output buffer size for psa_cipher_decrypt(), for any of the 1003 * supported key types and cipher algorithms. 1004 * 1005 * If the size of the output buffer is at least this large, it is guaranteed 1006 * that psa_cipher_decrypt() will not fail due to an insufficient buffer size. 1007 * 1008 * See also #PSA_CIPHER_DECRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). 1009 * 1010 * \param input_length Size of the input in bytes. 1011 */ 1012 #define PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(input_length) \ 1013 (input_length) 1014 1015 /** A sufficient output buffer size for psa_cipher_update(). 1016 * 1017 * If the size of the output buffer is at least this large, it is guaranteed 1018 * that psa_cipher_update() will not fail due to an insufficient buffer size. 1019 * The actual size of the output might be smaller in any given call. 1020 * 1021 * See also #PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(\p input_length). 1022 * 1023 * \param key_type A symmetric key type that is compatible with algorithm 1024 * alg. 1025 * \param alg A cipher algorithm (PSA_ALG_XXX value such that 1026 * #PSA_ALG_IS_CIPHER(\p alg) is true). 1027 * \param input_length Size of the input in bytes. 1028 * 1029 * \return A sufficient output size for the specified key type and 1030 * algorithm. If the key type or cipher algorithm is not 1031 * recognized, or the parameters are incompatible, return 0. 1032 */ 1033 #define PSA_CIPHER_UPDATE_OUTPUT_SIZE(key_type, alg, input_length) \ 1034 (PSA_ALG_IS_CIPHER(alg) ? \ 1035 (((alg) == PSA_ALG_CBC_PKCS7 || \ 1036 (alg) == PSA_ALG_CBC_NO_PADDING || \ 1037 (alg) == PSA_ALG_ECB_NO_PADDING) ? \ 1038 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \ 1039 input_length) : \ 1040 (input_length)) : \ 1041 0) 1042 1043 /** A sufficient output buffer size for psa_cipher_update(), for any of the 1044 * supported key types and cipher algorithms. 1045 * 1046 * If the size of the output buffer is at least this large, it is guaranteed 1047 * that psa_cipher_update() will not fail due to an insufficient buffer size. 1048 * 1049 * See also #PSA_CIPHER_UPDATE_OUTPUT_SIZE(\p key_type, \p alg, \p input_length). 1050 * 1051 * \param input_length Size of the input in bytes. 1052 */ 1053 #define PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(input_length) \ 1054 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, input_length)) 1055 1056 /** A sufficient ciphertext buffer size for psa_cipher_finish(). 1057 * 1058 * If the size of the ciphertext buffer is at least this large, it is 1059 * guaranteed that psa_cipher_finish() will not fail due to an insufficient 1060 * ciphertext buffer size. The actual size of the output might be smaller in 1061 * any given call. 1062 * 1063 * See also #PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE(). 1064 * 1065 * \param key_type A symmetric key type that is compatible with algorithm 1066 * alg. 1067 * \param alg A cipher algorithm (PSA_ALG_XXX value such that 1068 * #PSA_ALG_IS_CIPHER(\p alg) is true). 1069 * \return A sufficient output size for the specified key type and 1070 * algorithm. If the key type or cipher algorithm is not 1071 * recognized, or the parameters are incompatible, return 0. 1072 */ 1073 #define PSA_CIPHER_FINISH_OUTPUT_SIZE(key_type, alg) \ 1074 (PSA_ALG_IS_CIPHER(alg) ? \ 1075 (alg == PSA_ALG_CBC_PKCS7 ? \ 1076 PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \ 1077 0) : \ 1078 0) 1079 1080 /** A sufficient ciphertext buffer size for psa_cipher_finish(), for any of the 1081 * supported key types and cipher algorithms. 1082 * 1083 * See also #PSA_CIPHER_FINISH_OUTPUT_SIZE(\p key_type, \p alg). 1084 */ 1085 #define PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE \ 1086 (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE) 1087 1088 #endif /* PSA_CRYPTO_SIZES_H */ 1089