v2 / thirdparty / mbedtls / include / psa / crypto_sizes.h
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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 OR GPL-2.0-or-later
26 */
27
28#ifndef PSA_CRYPTO_SIZES_H
29#define PSA_CRYPTO_SIZES_H
30
31/*
32 * Include the build-time configuration information header. Here, we do not
33 * include `"mbedtls/build_info.h"` directly but `"psa/build_info.h"`, which
34 * is basically just an alias to it. This is to ease the maintenance of the
35 * TF-PSA-Crypto repository which has a different build system and
36 * configuration.
37 */
38#include "psa/build_info.h"
39
40#define PSA_BITS_TO_BYTES(bits) (((bits) + 7u) / 8u)
41#define PSA_BYTES_TO_BITS(bytes) ((bytes) * 8u)
42#define PSA_MAX_OF_THREE(a, b, c) ((a) <= (b) ? (b) <= (c) ? \
43 (c) : (b) : (a) <= (c) ? (c) : (a))
44
45#define PSA_ROUND_UP_TO_MULTIPLE(block_size, length) \
46 (((length) + (block_size) - 1) / (block_size) * (block_size))
47
48/** The size of the output of psa_hash_finish(), in bytes.
49 *
50 * This is also the hash size that psa_hash_verify() expects.
51 *
52 * \param alg A hash algorithm (\c PSA_ALG_XXX value such that
53 * #PSA_ALG_IS_HASH(\p alg) is true), or an HMAC algorithm
54 * (#PSA_ALG_HMAC(\c hash_alg) where \c hash_alg is a
55 * hash algorithm).
56 *
57 * \return The hash size for the specified hash algorithm.
58 * If the hash algorithm is not recognized, return 0.
59 */
60#define PSA_HASH_LENGTH(alg) \
61 ( \
62 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 16u : \
63 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 20u : \
64 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 20u : \
65 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 28u : \
66 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 32u : \
67 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 48u : \
68 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 64u : \
69 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 28u : \
70 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 32u : \
71 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 28u : \
72 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 32u : \
73 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 48u : \
74 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 64u : \
75 0u)
76
77/** The input block size of a hash algorithm, in bytes.
78 *
79 * Hash algorithms process their input data in blocks. Hash operations will
80 * retain any partial blocks until they have enough input to fill the block or
81 * until the operation is finished.
82 * This affects the output from psa_hash_suspend().
83 *
84 * \param alg A hash algorithm (\c PSA_ALG_XXX value such that
85 * PSA_ALG_IS_HASH(\p alg) is true).
86 *
87 * \return The block size in bytes for the specified hash algorithm.
88 * If the hash algorithm is not recognized, return 0.
89 * An implementation can return either 0 or the correct size for a
90 * hash algorithm that it recognizes, but does not support.
91 */
92#define PSA_HASH_BLOCK_LENGTH(alg) \
93 ( \
94 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_MD5 ? 64u : \
95 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_RIPEMD160 ? 64u : \
96 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_1 ? 64u : \
97 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_224 ? 64u : \
98 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_256 ? 64u : \
99 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_384 ? 128u : \
100 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512 ? 128u : \
101 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_224 ? 128u : \
102 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA_512_256 ? 128u : \
103 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_224 ? 144u : \
104 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_256 ? 136u : \
105 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_384 ? 104u : \
106 PSA_ALG_HMAC_GET_HASH(alg) == PSA_ALG_SHA3_512 ? 72u : \
107 0u)
108
109/** \def PSA_HASH_MAX_SIZE
110 *
111 * Maximum size of a hash.
112 *
113 * This macro expands to a compile-time constant integer. This value
114 * is the maximum size of a hash in bytes.
115 */
116/* Note: for HMAC-SHA-3, the block size is 144 bytes for HMAC-SHA3-224,
117 * 136 bytes for HMAC-SHA3-256, 104 bytes for SHA3-384, 72 bytes for
118 * HMAC-SHA3-512. */
119/* Note: PSA_HASH_MAX_SIZE should be kept in sync with MBEDTLS_MD_MAX_SIZE,
120 * see the note on MBEDTLS_MD_MAX_SIZE for details. */
121#if defined(PSA_WANT_ALG_SHA3_224)
122#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 144u
123#elif defined(PSA_WANT_ALG_SHA3_256)
124#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 136u
125#elif defined(PSA_WANT_ALG_SHA_512)
126#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128u
127#elif defined(PSA_WANT_ALG_SHA_384)
128#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 128u
129#elif defined(PSA_WANT_ALG_SHA3_384)
130#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 104u
131#elif defined(PSA_WANT_ALG_SHA3_512)
132#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 72u
133#elif defined(PSA_WANT_ALG_SHA_256)
134#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u
135#elif defined(PSA_WANT_ALG_SHA_224)
136#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u
137#else /* SHA-1 or smaller */
138#define PSA_HMAC_MAX_HASH_BLOCK_SIZE 64u
139#endif
140
141#if defined(PSA_WANT_ALG_SHA_512) || defined(PSA_WANT_ALG_SHA3_512)
142#define PSA_HASH_MAX_SIZE 64u
143#elif defined(PSA_WANT_ALG_SHA_384) || defined(PSA_WANT_ALG_SHA3_384)
144#define PSA_HASH_MAX_SIZE 48u
145#elif defined(PSA_WANT_ALG_SHA_256) || defined(PSA_WANT_ALG_SHA3_256)
146#define PSA_HASH_MAX_SIZE 32u
147#elif defined(PSA_WANT_ALG_SHA_224) || defined(PSA_WANT_ALG_SHA3_224)
148#define PSA_HASH_MAX_SIZE 28u
149#else /* SHA-1 or smaller */
150#define PSA_HASH_MAX_SIZE 20u
151#endif
152
153/** \def PSA_MAC_MAX_SIZE
154 *
155 * Maximum size of a MAC.
156 *
157 * This macro expands to a compile-time constant integer. This value
158 * is the maximum size of a MAC in bytes.
159 */
160/* All non-HMAC MACs have a maximum size that's smaller than the
161 * minimum possible value of PSA_HASH_MAX_SIZE in this implementation. */
162/* Note that the encoding of truncated MAC algorithms limits this value
163 * to 64 bytes.
164 */
165#define PSA_MAC_MAX_SIZE PSA_HASH_MAX_SIZE
166
167/** The length of a tag for an AEAD algorithm, in bytes.
168 *
169 * This macro can be used to allocate a buffer of sufficient size to store the
170 * tag output from psa_aead_finish().
171 *
172 * See also #PSA_AEAD_TAG_MAX_SIZE.
173 *
174 * \param key_type The type of the AEAD key.
175 * \param key_bits The size of the AEAD key in bits.
176 * \param alg An AEAD algorithm
177 * (\c PSA_ALG_XXX value such that
178 * #PSA_ALG_IS_AEAD(\p alg) is true).
179 *
180 * \return The tag length for the specified algorithm and key.
181 * If the AEAD algorithm does not have an identified
182 * tag that can be distinguished from the rest of
183 * the ciphertext, return 0.
184 * If the key type or AEAD algorithm is not
185 * recognized, or the parameters are incompatible,
186 * return 0.
187 */
188#define PSA_AEAD_TAG_LENGTH(key_type, key_bits, alg) \
189 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \
190 PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \
191 ((void) (key_bits), 0u))
192
193/** The maximum tag size for all supported AEAD algorithms, in bytes.
194 *
195 * See also #PSA_AEAD_TAG_LENGTH(\p key_type, \p key_bits, \p alg).
196 */
197#define PSA_AEAD_TAG_MAX_SIZE 16u
198
199/* The maximum size of an RSA key on this implementation, in bits.
200 * This is a vendor-specific macro.
201 *
202 * Mbed TLS does not set a hard limit on the size of RSA keys: any key
203 * whose parameters fit in a bignum is accepted. However large keys can
204 * induce a large memory usage and long computation times. Unlike other
205 * auxiliary macros in this file and in crypto.h, which reflect how the
206 * library is configured, this macro defines how the library is
207 * configured. This implementation refuses to import or generate an
208 * RSA key whose size is larger than the value defined here.
209 *
210 * Note that an implementation may set different size limits for different
211 * operations, and does not need to accept all key sizes up to the limit. */
212#define PSA_VENDOR_RSA_MAX_KEY_BITS 4096u
213
214/* The minimum size of an RSA key on this implementation, in bits.
215 * This is a vendor-specific macro.
216 *
217 * Limits RSA key generation to a minimum due to avoid accidental misuse.
218 * This value cannot be less than 128 bits.
219 */
220#if defined(MBEDTLS_RSA_GEN_KEY_MIN_BITS)
221#define PSA_VENDOR_RSA_GENERATE_MIN_KEY_BITS MBEDTLS_RSA_GEN_KEY_MIN_BITS
222#else
223#define PSA_VENDOR_RSA_GENERATE_MIN_KEY_BITS 1024
224#endif
225
226/* The maximum size of an DH key on this implementation, in bits.
227 * This is a vendor-specific macro.*/
228#if defined(PSA_WANT_DH_RFC7919_8192)
229#define PSA_VENDOR_FFDH_MAX_KEY_BITS 8192u
230#elif defined(PSA_WANT_DH_RFC7919_6144)
231#define PSA_VENDOR_FFDH_MAX_KEY_BITS 6144u
232#elif defined(PSA_WANT_DH_RFC7919_4096)
233#define PSA_VENDOR_FFDH_MAX_KEY_BITS 4096u
234#elif defined(PSA_WANT_DH_RFC7919_3072)
235#define PSA_VENDOR_FFDH_MAX_KEY_BITS 3072u
236#elif defined(PSA_WANT_DH_RFC7919_2048)
237#define PSA_VENDOR_FFDH_MAX_KEY_BITS 2048u
238#else
239#define PSA_VENDOR_FFDH_MAX_KEY_BITS 0u
240#endif
241
242/* The maximum size of an ECC key on this implementation, in bits.
243 * This is a vendor-specific macro. */
244#if defined(PSA_WANT_ECC_SECP_R1_521)
245#define PSA_VENDOR_ECC_MAX_CURVE_BITS 521u
246#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_512)
247#define PSA_VENDOR_ECC_MAX_CURVE_BITS 512u
248#elif defined(PSA_WANT_ECC_MONTGOMERY_448)
249#define PSA_VENDOR_ECC_MAX_CURVE_BITS 448u
250#elif defined(PSA_WANT_ECC_SECP_R1_384)
251#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384u
252#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_384)
253#define PSA_VENDOR_ECC_MAX_CURVE_BITS 384u
254#elif defined(PSA_WANT_ECC_SECP_R1_256)
255#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u
256#elif defined(PSA_WANT_ECC_SECP_K1_256)
257#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u
258#elif defined(PSA_WANT_ECC_BRAINPOOL_P_R1_256)
259#define PSA_VENDOR_ECC_MAX_CURVE_BITS 256u
260#elif defined(PSA_WANT_ECC_MONTGOMERY_255)
261#define PSA_VENDOR_ECC_MAX_CURVE_BITS 255u
262#elif defined(PSA_WANT_ECC_SECP_R1_224)
263#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224u
264#elif defined(PSA_WANT_ECC_SECP_K1_224)
265#define PSA_VENDOR_ECC_MAX_CURVE_BITS 224u
266#elif defined(PSA_WANT_ECC_SECP_R1_192)
267#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192u
268#elif defined(PSA_WANT_ECC_SECP_K1_192)
269#define PSA_VENDOR_ECC_MAX_CURVE_BITS 192u
270#else
271#define PSA_VENDOR_ECC_MAX_CURVE_BITS 0u
272#endif
273
274/** This macro returns the maximum supported length of the PSK for the
275 * TLS-1.2 PSK-to-MS key derivation
276 * (#PSA_ALG_TLS12_PSK_TO_MS(\c hash_alg)).
277 *
278 * The maximum supported length does not depend on the chosen hash algorithm.
279 *
280 * Quoting RFC 4279, Sect 5.3:
281 * TLS implementations supporting these ciphersuites MUST support
282 * arbitrary PSK identities up to 128 octets in length, and arbitrary
283 * PSKs up to 64 octets in length. Supporting longer identities and
284 * keys is RECOMMENDED.
285 *
286 * Therefore, no implementation should define a value smaller than 64
287 * for #PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE.
288 */
289#define PSA_TLS12_PSK_TO_MS_PSK_MAX_SIZE 128u
290
291/* The expected size of input passed to psa_tls12_ecjpake_to_pms_input,
292 * which is expected to work with P-256 curve only. */
293#define PSA_TLS12_ECJPAKE_TO_PMS_INPUT_SIZE 65u
294
295/* The size of a serialized K.X coordinate to be used in
296 * psa_tls12_ecjpake_to_pms_input. This function only accepts the P-256
297 * curve. */
298#define PSA_TLS12_ECJPAKE_TO_PMS_DATA_SIZE 32u
299
300/* The maximum number of iterations for PBKDF2 on this implementation, in bits.
301 * This is a vendor-specific macro. This can be configured if necessary */
302#define PSA_VENDOR_PBKDF2_MAX_ITERATIONS 0xffffffffU
303
304/** The maximum size of a block cipher. */
305#define PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE 16u
306
307/** The size of the output of psa_mac_sign_finish(), in bytes.
308 *
309 * This is also the MAC size that psa_mac_verify_finish() expects.
310 *
311 * \warning This macro may evaluate its arguments multiple times or
312 * zero times, so you should not pass arguments that contain
313 * side effects.
314 *
315 * \param key_type The type of the MAC key.
316 * \param key_bits The size of the MAC key in bits.
317 * \param alg A MAC algorithm (\c PSA_ALG_XXX value such that
318 * #PSA_ALG_IS_MAC(\p alg) is true).
319 *
320 * \return The MAC size for the specified algorithm with
321 * the specified key parameters.
322 * \return 0 if the MAC algorithm is not recognized.
323 * \return Either 0 or the correct size for a MAC algorithm that
324 * the implementation recognizes, but does not support.
325 * \return Unspecified if the key parameters are not consistent
326 * with the algorithm.
327 */
328#define PSA_MAC_LENGTH(key_type, key_bits, alg) \
329 ((alg) & PSA_ALG_MAC_TRUNCATION_MASK ? PSA_MAC_TRUNCATED_LENGTH(alg) : \
330 PSA_ALG_IS_HMAC(alg) ? PSA_HASH_LENGTH(PSA_ALG_HMAC_GET_HASH(alg)) : \
331 PSA_ALG_IS_BLOCK_CIPHER_MAC(alg) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \
332 ((void) (key_type), (void) (key_bits), 0u))
333
334/** The maximum size of the output of psa_aead_encrypt(), in bytes.
335 *
336 * If the size of the ciphertext buffer is at least this large, it is
337 * guaranteed that psa_aead_encrypt() will not fail due to an
338 * insufficient buffer size. Depending on the algorithm, the actual size of
339 * the ciphertext may be smaller.
340 *
341 * See also #PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(\p plaintext_length).
342 *
343 * \warning This macro may evaluate its arguments multiple times or
344 * zero times, so you should not pass arguments that contain
345 * side effects.
346 *
347 * \param key_type A symmetric key type that is
348 * compatible with algorithm \p alg.
349 * \param alg An AEAD algorithm
350 * (\c PSA_ALG_XXX value such that
351 * #PSA_ALG_IS_AEAD(\p alg) is true).
352 * \param plaintext_length Size of the plaintext in bytes.
353 *
354 * \return The AEAD ciphertext size for the specified
355 * algorithm.
356 * If the key type or AEAD algorithm is not
357 * recognized, or the parameters are incompatible,
358 * return 0.
359 */
360#define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(key_type, alg, plaintext_length) \
361 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \
362 (plaintext_length) + PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \
363 0u)
364
365/** A sufficient output buffer size for psa_aead_encrypt(), for any of the
366 * supported key types and AEAD algorithms.
367 *
368 * If the size of the ciphertext buffer is at least this large, it is guaranteed
369 * that psa_aead_encrypt() will not fail due to an insufficient buffer size.
370 *
371 * \note This macro returns a compile-time constant if its arguments are
372 * compile-time constants.
373 *
374 * See also #PSA_AEAD_ENCRYPT_OUTPUT_SIZE(\p key_type, \p alg,
375 * \p plaintext_length).
376 *
377 * \param plaintext_length Size of the plaintext in bytes.
378 *
379 * \return A sufficient output buffer size for any of the
380 * supported key types and AEAD algorithms.
381 *
382 */
383#define PSA_AEAD_ENCRYPT_OUTPUT_MAX_SIZE(plaintext_length) \
384 ((plaintext_length) + PSA_AEAD_TAG_MAX_SIZE)
385
386
387/** The maximum size of the output of psa_aead_decrypt(), in bytes.
388 *
389 * If the size of the plaintext buffer is at least this large, it is
390 * guaranteed that psa_aead_decrypt() will not fail due to an
391 * insufficient buffer size. Depending on the algorithm, the actual size of
392 * the plaintext may be smaller.
393 *
394 * See also #PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(\p ciphertext_length).
395 *
396 * \warning This macro may evaluate its arguments multiple times or
397 * zero times, so you should not pass arguments that contain
398 * side effects.
399 *
400 * \param key_type A symmetric key type that is
401 * compatible with algorithm \p alg.
402 * \param alg An AEAD algorithm
403 * (\c PSA_ALG_XXX value such that
404 * #PSA_ALG_IS_AEAD(\p alg) is true).
405 * \param ciphertext_length Size of the plaintext in bytes.
406 *
407 * \return The AEAD ciphertext size for the specified
408 * algorithm.
409 * If the key type or AEAD algorithm is not
410 * recognized, or the parameters are incompatible,
411 * return 0.
412 */
413#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(key_type, alg, ciphertext_length) \
414 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \
415 (ciphertext_length) > PSA_ALG_AEAD_GET_TAG_LENGTH(alg) ? \
416 (ciphertext_length) - PSA_ALG_AEAD_GET_TAG_LENGTH(alg) : \
417 0u)
418
419/** A sufficient output buffer size for psa_aead_decrypt(), for any of the
420 * supported key types and AEAD algorithms.
421 *
422 * If the size of the plaintext buffer is at least this large, it is guaranteed
423 * that psa_aead_decrypt() will not fail due to an insufficient buffer size.
424 *
425 * \note This macro returns a compile-time constant if its arguments are
426 * compile-time constants.
427 *
428 * See also #PSA_AEAD_DECRYPT_OUTPUT_SIZE(\p key_type, \p alg,
429 * \p ciphertext_length).
430 *
431 * \param ciphertext_length Size of the ciphertext in bytes.
432 *
433 * \return A sufficient output buffer size for any of the
434 * supported key types and AEAD algorithms.
435 *
436 */
437#define PSA_AEAD_DECRYPT_OUTPUT_MAX_SIZE(ciphertext_length) \
438 (ciphertext_length)
439
440/** The default nonce size for an AEAD algorithm, in bytes.
441 *
442 * This macro can be used to allocate a buffer of sufficient size to
443 * store the nonce output from #psa_aead_generate_nonce().
444 *
445 * See also #PSA_AEAD_NONCE_MAX_SIZE.
446 *
447 * \note This is not the maximum size of nonce supported as input to
448 * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(),
449 * just the default size that is generated by #psa_aead_generate_nonce().
450 *
451 * \warning This macro may evaluate its arguments multiple times or
452 * zero times, so you should not pass arguments that contain
453 * side effects.
454 *
455 * \param key_type A symmetric key type that is compatible with
456 * algorithm \p alg.
457 *
458 * \param alg An AEAD algorithm (\c PSA_ALG_XXX value such that
459 * #PSA_ALG_IS_AEAD(\p alg) is true).
460 *
461 * \return The default nonce size for the specified key type and algorithm.
462 * If the key type or AEAD algorithm is not recognized,
463 * or the parameters are incompatible, return 0.
464 */
465#define PSA_AEAD_NONCE_LENGTH(key_type, alg) \
466 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) == 16 ? \
467 MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_CCM) ? 13u : \
468 MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_GCM) ? 12u : \
469 0u : \
470 (key_type) == PSA_KEY_TYPE_CHACHA20 && \
471 MBEDTLS_PSA_ALG_AEAD_EQUAL(alg, PSA_ALG_CHACHA20_POLY1305) ? 12u : \
472 0u)
473
474/** The maximum default nonce size among all supported pairs of key types and
475 * AEAD algorithms, in bytes.
476 *
477 * This is equal to or greater than any value that #PSA_AEAD_NONCE_LENGTH()
478 * may return.
479 *
480 * \note This is not the maximum size of nonce supported as input to
481 * #psa_aead_set_nonce(), #psa_aead_encrypt() or #psa_aead_decrypt(),
482 * just the largest size that may be generated by
483 * #psa_aead_generate_nonce().
484 */
485#define PSA_AEAD_NONCE_MAX_SIZE 13u
486
487/** A sufficient output buffer size for psa_aead_update().
488 *
489 * If the size of the output buffer is at least this large, it is
490 * guaranteed that psa_aead_update() will not fail due to an
491 * insufficient buffer size. The actual size of the output may be smaller
492 * in any given call.
493 *
494 * See also #PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(\p input_length).
495 *
496 * \warning This macro may evaluate its arguments multiple times or
497 * zero times, so you should not pass arguments that contain
498 * side effects.
499 *
500 * \param key_type A symmetric key type that is
501 * compatible with algorithm \p alg.
502 * \param alg An AEAD algorithm
503 * (\c PSA_ALG_XXX value such that
504 * #PSA_ALG_IS_AEAD(\p alg) is true).
505 * \param input_length Size of the input in bytes.
506 *
507 * \return A sufficient output buffer size for the specified
508 * algorithm.
509 * If the key type or AEAD algorithm is not
510 * recognized, or the parameters are incompatible,
511 * return 0.
512 */
513/* For all the AEAD modes defined in this specification, it is possible
514 * to emit output without delay. However, hardware may not always be
515 * capable of this. So for modes based on a block cipher, allow the
516 * implementation to delay the output until it has a full block. */
517#define PSA_AEAD_UPDATE_OUTPUT_SIZE(key_type, alg, input_length) \
518 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 ? \
519 PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
520 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), (input_length)) : \
521 (input_length) : \
522 0u)
523
524/** A sufficient output buffer size for psa_aead_update(), for any of the
525 * supported key types and AEAD algorithms.
526 *
527 * If the size of the output buffer is at least this large, it is guaranteed
528 * that psa_aead_update() will not fail due to an insufficient buffer size.
529 *
530 * See also #PSA_AEAD_UPDATE_OUTPUT_SIZE(\p key_type, \p alg, \p input_length).
531 *
532 * \param input_length Size of the input in bytes.
533 */
534#define PSA_AEAD_UPDATE_OUTPUT_MAX_SIZE(input_length) \
535 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, (input_length)))
536
537/** A sufficient ciphertext buffer size for psa_aead_finish().
538 *
539 * If the size of the ciphertext buffer is at least this large, it is
540 * guaranteed that psa_aead_finish() will not fail due to an
541 * insufficient ciphertext buffer size. The actual size of the output may
542 * be smaller in any given call.
543 *
544 * See also #PSA_AEAD_FINISH_OUTPUT_MAX_SIZE.
545 *
546 * \param key_type A symmetric key type that is
547 compatible with algorithm \p alg.
548 * \param alg An AEAD algorithm
549 * (\c PSA_ALG_XXX value such that
550 * #PSA_ALG_IS_AEAD(\p alg) is true).
551 *
552 * \return A sufficient ciphertext buffer size for the
553 * specified algorithm.
554 * If the key type or AEAD algorithm is not
555 * recognized, or the parameters are incompatible,
556 * return 0.
557 */
558#define PSA_AEAD_FINISH_OUTPUT_SIZE(key_type, alg) \
559 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \
560 PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
561 PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \
562 0u)
563
564/** A sufficient ciphertext buffer size for psa_aead_finish(), for any of the
565 * supported key types and AEAD algorithms.
566 *
567 * See also #PSA_AEAD_FINISH_OUTPUT_SIZE(\p key_type, \p alg).
568 */
569#define PSA_AEAD_FINISH_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE)
570
571/** A sufficient plaintext buffer size for psa_aead_verify().
572 *
573 * If the size of the plaintext buffer is at least this large, it is
574 * guaranteed that psa_aead_verify() will not fail due to an
575 * insufficient plaintext buffer size. The actual size of the output may
576 * be smaller in any given call.
577 *
578 * See also #PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE.
579 *
580 * \param key_type A symmetric key type that is
581 * compatible with algorithm \p alg.
582 * \param alg An AEAD algorithm
583 * (\c PSA_ALG_XXX value such that
584 * #PSA_ALG_IS_AEAD(\p alg) is true).
585 *
586 * \return A sufficient plaintext buffer size for the
587 * specified algorithm.
588 * If the key type or AEAD algorithm is not
589 * recognized, or the parameters are incompatible,
590 * return 0.
591 */
592#define PSA_AEAD_VERIFY_OUTPUT_SIZE(key_type, alg) \
593 (PSA_AEAD_NONCE_LENGTH(key_type, alg) != 0 && \
594 PSA_ALG_IS_AEAD_ON_BLOCK_CIPHER(alg) ? \
595 PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \
596 0u)
597
598/** A sufficient plaintext buffer size for psa_aead_verify(), for any of the
599 * supported key types and AEAD algorithms.
600 *
601 * See also #PSA_AEAD_VERIFY_OUTPUT_SIZE(\p key_type, \p alg).
602 */
603#define PSA_AEAD_VERIFY_OUTPUT_MAX_SIZE (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE)
604
605#define PSA_RSA_MINIMUM_PADDING_SIZE(alg) \
606 (PSA_ALG_IS_RSA_OAEP(alg) ? \
607 2u * PSA_HASH_LENGTH(PSA_ALG_RSA_OAEP_GET_HASH(alg)) + 1u : \
608 11u /*PKCS#1v1.5*/)
609
610/**
611 * \brief ECDSA signature size for a given curve bit size
612 *
613 * \param curve_bits Curve size in bits.
614 * \return Signature size in bytes.
615 *
616 * \note This macro returns a compile-time constant if its argument is one.
617 */
618#define PSA_ECDSA_SIGNATURE_SIZE(curve_bits) \
619 (PSA_BITS_TO_BYTES(curve_bits) * 2u)
620
621/** Sufficient signature buffer size for psa_sign_hash().
622 *
623 * This macro returns a sufficient buffer size for a signature using a key
624 * of the specified type and size, with the specified algorithm.
625 * Note that the actual size of the signature may be smaller
626 * (some algorithms produce a variable-size signature).
627 *
628 * \warning This function may call its arguments multiple times or
629 * zero times, so you should not pass arguments that contain
630 * side effects.
631 *
632 * \param key_type An asymmetric key type (this may indifferently be a
633 * key pair type or a public key type).
634 * \param key_bits The size of the key in bits.
635 * \param alg The signature algorithm.
636 *
637 * \return If the parameters are valid and supported, return
638 * a buffer size in bytes that guarantees that
639 * psa_sign_hash() will not fail with
640 * #PSA_ERROR_BUFFER_TOO_SMALL.
641 * If the parameters are a valid combination that is not supported,
642 * return either a sensible size or 0.
643 * If the parameters are not valid, the
644 * return value is unspecified.
645 */
646#define PSA_SIGN_OUTPUT_SIZE(key_type, key_bits, alg) \
647 (PSA_KEY_TYPE_IS_RSA(key_type) ? ((void) alg, PSA_BITS_TO_BYTES(key_bits)) : \
648 PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_ECDSA_SIGNATURE_SIZE(key_bits) : \
649 ((void) alg, 0u))
650
651#define PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE \
652 PSA_ECDSA_SIGNATURE_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)
653
654/** \def PSA_SIGNATURE_MAX_SIZE
655 *
656 * Maximum size of an asymmetric signature.
657 *
658 * This macro expands to a compile-time constant integer. This value
659 * is the maximum size of a signature in bytes.
660 */
661#define PSA_SIGNATURE_MAX_SIZE 1
662
663#if (defined(PSA_WANT_ALG_ECDSA) || defined(PSA_WANT_ALG_DETERMINISTIC_ECDSA)) && \
664 (PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE > PSA_SIGNATURE_MAX_SIZE)
665#undef PSA_SIGNATURE_MAX_SIZE
666#define PSA_SIGNATURE_MAX_SIZE PSA_VENDOR_ECDSA_SIGNATURE_MAX_SIZE
667#endif
668#if (defined(PSA_WANT_ALG_RSA_PKCS1V15_SIGN) || defined(PSA_WANT_ALG_RSA_PSS)) && \
669 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS) > PSA_SIGNATURE_MAX_SIZE)
670#undef PSA_SIGNATURE_MAX_SIZE
671#define PSA_SIGNATURE_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS)
672#endif
673
674/** Sufficient output buffer size for psa_asymmetric_encrypt().
675 *
676 * This macro returns a sufficient buffer size for a ciphertext produced using
677 * a key of the specified type and size, with the specified algorithm.
678 * Note that the actual size of the ciphertext may be smaller, depending
679 * on the algorithm.
680 *
681 * \warning This function may call its arguments multiple times or
682 * zero times, so you should not pass arguments that contain
683 * side effects.
684 *
685 * \param key_type An asymmetric key type (this may indifferently be a
686 * key pair type or a public key type).
687 * \param key_bits The size of the key in bits.
688 * \param alg The asymmetric encryption algorithm.
689 *
690 * \return If the parameters are valid and supported, return
691 * a buffer size in bytes that guarantees that
692 * psa_asymmetric_encrypt() will not fail with
693 * #PSA_ERROR_BUFFER_TOO_SMALL.
694 * If the parameters are a valid combination that is not supported,
695 * return either a sensible size or 0.
696 * If the parameters are not valid, the
697 * return value is unspecified.
698 */
699#define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \
700 (PSA_KEY_TYPE_IS_RSA(key_type) ? \
701 ((void) alg, PSA_BITS_TO_BYTES(key_bits)) : \
702 0u)
703
704/** A sufficient output buffer size for psa_asymmetric_encrypt(), for any
705 * supported asymmetric encryption.
706 *
707 * See also #PSA_ASYMMETRIC_ENCRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg).
708 */
709/* This macro assumes that RSA is the only supported asymmetric encryption. */
710#define PSA_ASYMMETRIC_ENCRYPT_OUTPUT_MAX_SIZE \
711 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS))
712
713/** Sufficient output buffer size for psa_asymmetric_decrypt().
714 *
715 * This macro returns a sufficient buffer size for a plaintext produced using
716 * a key of the specified type and size, with the specified algorithm.
717 * Note that the actual size of the plaintext may be smaller, depending
718 * on the algorithm.
719 *
720 * \warning This function may call its arguments multiple times or
721 * zero times, so you should not pass arguments that contain
722 * side effects.
723 *
724 * \param key_type An asymmetric key type (this may indifferently be a
725 * key pair type or a public key type).
726 * \param key_bits The size of the key in bits.
727 * \param alg The asymmetric encryption algorithm.
728 *
729 * \return If the parameters are valid and supported, return
730 * a buffer size in bytes that guarantees that
731 * psa_asymmetric_decrypt() will not fail with
732 * #PSA_ERROR_BUFFER_TOO_SMALL.
733 * If the parameters are a valid combination that is not supported,
734 * return either a sensible size or 0.
735 * If the parameters are not valid, the
736 * return value is unspecified.
737 */
738#define PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(key_type, key_bits, alg) \
739 (PSA_KEY_TYPE_IS_RSA(key_type) ? \
740 PSA_BITS_TO_BYTES(key_bits) - PSA_RSA_MINIMUM_PADDING_SIZE(alg) : \
741 0u)
742
743/** A sufficient output buffer size for psa_asymmetric_decrypt(), for any
744 * supported asymmetric decryption.
745 *
746 * This macro assumes that RSA is the only supported asymmetric encryption.
747 *
748 * See also #PSA_ASYMMETRIC_DECRYPT_OUTPUT_SIZE(\p key_type, \p key_bits, \p alg).
749 */
750#define PSA_ASYMMETRIC_DECRYPT_OUTPUT_MAX_SIZE \
751 (PSA_BITS_TO_BYTES(PSA_VENDOR_RSA_MAX_KEY_BITS))
752
753/* Maximum size of the ASN.1 encoding of an INTEGER with the specified
754 * number of bits.
755 *
756 * This definition assumes that bits <= 2^19 - 9 so that the length field
757 * is at most 3 bytes. The length of the encoding is the length of the
758 * bit string padded to a whole number of bytes plus:
759 * - 1 type byte;
760 * - 1 to 3 length bytes;
761 * - 0 to 1 bytes of leading 0 due to the sign bit.
762 */
763#define PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(bits) \
764 ((bits) / 8u + 5u)
765
766/* Maximum size of the export encoding of an RSA public key.
767 * Assumes that the public exponent is less than 2^32.
768 *
769 * RSAPublicKey ::= SEQUENCE {
770 * modulus INTEGER, -- n
771 * publicExponent INTEGER } -- e
772 *
773 * - 4 bytes of SEQUENCE overhead;
774 * - n : INTEGER;
775 * - 7 bytes for the public exponent.
776 */
777#define PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) \
778 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) + 11u)
779
780/* Maximum size of the export encoding of an RSA key pair.
781 * Assumes that the public exponent is less than 2^32 and that the size
782 * difference between the two primes is at most 1 bit.
783 *
784 * RSAPrivateKey ::= SEQUENCE {
785 * version Version, -- 0
786 * modulus INTEGER, -- N-bit
787 * publicExponent INTEGER, -- 32-bit
788 * privateExponent INTEGER, -- N-bit
789 * prime1 INTEGER, -- N/2-bit
790 * prime2 INTEGER, -- N/2-bit
791 * exponent1 INTEGER, -- N/2-bit
792 * exponent2 INTEGER, -- N/2-bit
793 * coefficient INTEGER, -- N/2-bit
794 * }
795 *
796 * - 4 bytes of SEQUENCE overhead;
797 * - 3 bytes of version;
798 * - 7 half-size INTEGERs plus 2 full-size INTEGERs,
799 * overapproximated as 9 half-size INTEGERS;
800 * - 7 bytes for the public exponent.
801 */
802#define PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) \
803 (9u * PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE((key_bits) / 2u + 1u) + 14u)
804
805/* Maximum size of the export encoding of a DSA public key.
806 *
807 * SubjectPublicKeyInfo ::= SEQUENCE {
808 * algorithm AlgorithmIdentifier,
809 * subjectPublicKey BIT STRING } -- contains DSAPublicKey
810 * AlgorithmIdentifier ::= SEQUENCE {
811 * algorithm OBJECT IDENTIFIER,
812 * parameters Dss-Params } -- SEQUENCE of 3 INTEGERs
813 * DSAPublicKey ::= INTEGER -- public key, Y
814 *
815 * - 3 * 4 bytes of SEQUENCE overhead;
816 * - 1 + 1 + 7 bytes of algorithm (DSA OID);
817 * - 4 bytes of BIT STRING overhead;
818 * - 3 full-size INTEGERs (p, g, y);
819 * - 1 + 1 + 32 bytes for 1 sub-size INTEGER (q <= 256 bits).
820 */
821#define PSA_KEY_EXPORT_DSA_PUBLIC_KEY_MAX_SIZE(key_bits) \
822 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3u + 59u)
823
824/* Maximum size of the export encoding of a DSA key pair.
825 *
826 * DSAPrivateKey ::= SEQUENCE {
827 * version Version, -- 0
828 * prime INTEGER, -- p
829 * subprime INTEGER, -- q
830 * generator INTEGER, -- g
831 * public INTEGER, -- y
832 * private INTEGER, -- x
833 * }
834 *
835 * - 4 bytes of SEQUENCE overhead;
836 * - 3 bytes of version;
837 * - 3 full-size INTEGERs (p, g, y);
838 * - 2 * (1 + 1 + 32) bytes for 2 sub-size INTEGERs (q, x <= 256 bits).
839 */
840#define PSA_KEY_EXPORT_DSA_KEY_PAIR_MAX_SIZE(key_bits) \
841 (PSA_KEY_EXPORT_ASN1_INTEGER_MAX_SIZE(key_bits) * 3u + 75u)
842
843/* Maximum size of the export encoding of an ECC public key.
844 *
845 * The representation of an ECC public key is:
846 * - The byte 0x04;
847 * - `x_P` as a `ceiling(m/8)`-byte string, big-endian;
848 * - `y_P` as a `ceiling(m/8)`-byte string, big-endian;
849 * - where m is the bit size associated with the curve.
850 *
851 * - 1 byte + 2 * point size.
852 */
853#define PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) \
854 (2u * PSA_BITS_TO_BYTES(key_bits) + 1u)
855
856/* Maximum size of the export encoding of an ECC key pair.
857 *
858 * An ECC key pair is represented by the secret value.
859 */
860#define PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) \
861 (PSA_BITS_TO_BYTES(key_bits))
862
863/* Maximum size of the export encoding of an DH key pair.
864 *
865 * An DH key pair is represented by the secret value.
866 */
867#define PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(key_bits) \
868 (PSA_BITS_TO_BYTES(key_bits))
869
870/* Maximum size of the export encoding of an DH public key.
871 */
872#define PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_MAX_SIZE(key_bits) \
873 (PSA_BITS_TO_BYTES(key_bits))
874
875/** Sufficient output buffer size for psa_export_key() or
876 * psa_export_public_key().
877 *
878 * This macro returns a compile-time constant if its arguments are
879 * compile-time constants.
880 *
881 * \warning This macro may evaluate its arguments multiple times or
882 * zero times, so you should not pass arguments that contain
883 * side effects.
884 *
885 * The following code illustrates how to allocate enough memory to export
886 * a key by querying the key type and size at runtime.
887 * \code{c}
888 * psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
889 * psa_status_t status;
890 * status = psa_get_key_attributes(key, &attributes);
891 * if (status != PSA_SUCCESS) handle_error(...);
892 * psa_key_type_t key_type = psa_get_key_type(&attributes);
893 * size_t key_bits = psa_get_key_bits(&attributes);
894 * size_t buffer_size = PSA_EXPORT_KEY_OUTPUT_SIZE(key_type, key_bits);
895 * psa_reset_key_attributes(&attributes);
896 * uint8_t *buffer = malloc(buffer_size);
897 * if (buffer == NULL) handle_error(...);
898 * size_t buffer_length;
899 * status = psa_export_key(key, buffer, buffer_size, &buffer_length);
900 * if (status != PSA_SUCCESS) handle_error(...);
901 * \endcode
902 *
903 * \param key_type A supported key type.
904 * \param key_bits The size of the key in bits.
905 *
906 * \return If the parameters are valid and supported, return
907 * a buffer size in bytes that guarantees that
908 * psa_export_key() or psa_export_public_key() will not fail with
909 * #PSA_ERROR_BUFFER_TOO_SMALL.
910 * If the parameters are a valid combination that is not supported,
911 * return either a sensible size or 0.
912 * If the parameters are not valid, the return value is unspecified.
913 */
914#define PSA_EXPORT_KEY_OUTPUT_SIZE(key_type, key_bits) \
915 ((key_type) == PSA_KEY_TYPE_RSA_KEY_PAIR ? PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(key_bits) : \
916 (key_type) == PSA_KEY_TYPE_RSA_PUBLIC_KEY ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \
917 PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) ? PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(key_bits) : \
918 PSA_KEY_TYPE_IS_ECC_PUBLIC_KEY(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \
919 PSA_BITS_TO_BYTES(key_bits)) /*unstructured; FFDH public or private*/
920
921/** Sufficient output buffer size for psa_export_public_key().
922 *
923 * This macro returns a compile-time constant if its arguments are
924 * compile-time constants.
925 *
926 * \warning This macro may evaluate its arguments multiple times or
927 * zero times, so you should not pass arguments that contain
928 * side effects.
929 *
930 * The following code illustrates how to allocate enough memory to export
931 * a public key by querying the key type and size at runtime.
932 * \code{c}
933 * psa_key_attributes_t attributes = PSA_KEY_ATTRIBUTES_INIT;
934 * psa_status_t status;
935 * status = psa_get_key_attributes(key, &attributes);
936 * if (status != PSA_SUCCESS) handle_error(...);
937 * psa_key_type_t key_type = psa_get_key_type(&attributes);
938 * size_t key_bits = psa_get_key_bits(&attributes);
939 * size_t buffer_size = PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(key_type, key_bits);
940 * psa_reset_key_attributes(&attributes);
941 * uint8_t *buffer = malloc(buffer_size);
942 * if (buffer == NULL) handle_error(...);
943 * size_t buffer_length;
944 * status = psa_export_public_key(key, buffer, buffer_size, &buffer_length);
945 * if (status != PSA_SUCCESS) handle_error(...);
946 * \endcode
947 *
948 * \param key_type A public key or key pair key type.
949 * \param key_bits The size of the key in bits.
950 *
951 * \return If the parameters are valid and supported, return
952 * a buffer size in bytes that guarantees that
953 * psa_export_public_key() will not fail with
954 * #PSA_ERROR_BUFFER_TOO_SMALL.
955 * If the parameters are a valid combination that is not
956 * supported, return either a sensible size or 0.
957 * If the parameters are not valid,
958 * the return value is unspecified.
959 *
960 * If the parameters are valid and supported,
961 * return the same result as
962 * #PSA_EXPORT_KEY_OUTPUT_SIZE(
963 * \p #PSA_KEY_TYPE_PUBLIC_KEY_OF_KEY_PAIR(\p key_type),
964 * \p key_bits).
965 */
966#define PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(key_type, key_bits) \
967 (PSA_KEY_TYPE_IS_RSA(key_type) ? PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(key_bits) : \
968 PSA_KEY_TYPE_IS_ECC(key_type) ? PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(key_bits) : \
969 PSA_KEY_TYPE_IS_DH(key_type) ? PSA_BITS_TO_BYTES(key_bits) : \
970 0u)
971
972/** Sufficient buffer size for exporting any asymmetric key pair.
973 *
974 * This macro expands to a compile-time constant integer. This value is
975 * a sufficient buffer size when calling psa_export_key() to export any
976 * asymmetric key pair, regardless of the exact key type and key size.
977 *
978 * See also #PSA_EXPORT_KEY_OUTPUT_SIZE(\p key_type, \p key_bits).
979 */
980#define PSA_EXPORT_KEY_PAIR_MAX_SIZE 1
981
982#if defined(PSA_WANT_KEY_TYPE_ECC_KEY_PAIR_BASIC) && \
983 (PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) > \
984 PSA_EXPORT_KEY_PAIR_MAX_SIZE)
985#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE
986#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \
987 PSA_KEY_EXPORT_ECC_KEY_PAIR_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)
988#endif
989#if defined(PSA_WANT_KEY_TYPE_RSA_KEY_PAIR_BASIC) && \
990 (PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \
991 PSA_EXPORT_KEY_PAIR_MAX_SIZE)
992#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE
993#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \
994 PSA_KEY_EXPORT_RSA_KEY_PAIR_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS)
995#endif
996#if defined(PSA_WANT_KEY_TYPE_DH_KEY_PAIR_BASIC) && \
997 (PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) > \
998 PSA_EXPORT_KEY_PAIR_MAX_SIZE)
999#undef PSA_EXPORT_KEY_PAIR_MAX_SIZE
1000#define PSA_EXPORT_KEY_PAIR_MAX_SIZE \
1001 PSA_KEY_EXPORT_FFDH_KEY_PAIR_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS)
1002#endif
1003
1004/** Sufficient buffer size for exporting any asymmetric public key.
1005 *
1006 * This macro expands to a compile-time constant integer. This value is
1007 * a sufficient buffer size when calling psa_export_key() or
1008 * psa_export_public_key() to export any asymmetric public key,
1009 * regardless of the exact key type and key size.
1010 *
1011 * See also #PSA_EXPORT_PUBLIC_KEY_OUTPUT_SIZE(\p key_type, \p key_bits).
1012 */
1013#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE 1
1014
1015#if defined(PSA_WANT_KEY_TYPE_ECC_PUBLIC_KEY) && \
1016 (PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS) > \
1017 PSA_EXPORT_PUBLIC_KEY_MAX_SIZE)
1018#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE
1019#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \
1020 PSA_KEY_EXPORT_ECC_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_ECC_MAX_CURVE_BITS)
1021#endif
1022#if defined(PSA_WANT_KEY_TYPE_RSA_PUBLIC_KEY) && \
1023 (PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS) > \
1024 PSA_EXPORT_PUBLIC_KEY_MAX_SIZE)
1025#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE
1026#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \
1027 PSA_KEY_EXPORT_RSA_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_RSA_MAX_KEY_BITS)
1028#endif
1029#if defined(PSA_WANT_KEY_TYPE_DH_PUBLIC_KEY) && \
1030 (PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS) > \
1031 PSA_EXPORT_PUBLIC_KEY_MAX_SIZE)
1032#undef PSA_EXPORT_PUBLIC_KEY_MAX_SIZE
1033#define PSA_EXPORT_PUBLIC_KEY_MAX_SIZE \
1034 PSA_KEY_EXPORT_FFDH_PUBLIC_KEY_MAX_SIZE(PSA_VENDOR_FFDH_MAX_KEY_BITS)
1035#endif
1036
1037/* This is the name that was standardized in PSA Crypto v1.3 */
1038#define PSA_EXPORT_ASYMMETRIC_KEY_MAX_SIZE \
1039 ((PSA_EXPORT_KEY_PAIR_MAX_SIZE > PSA_EXPORT_PUBLIC_KEY_MAX_SIZE) ? \
1040 PSA_EXPORT_KEY_PAIR_MAX_SIZE : PSA_EXPORT_PUBLIC_KEY_MAX_SIZE)
1041
1042/* This is our old custom name from before it was in the spec,
1043 * keep it around in case users were relying on it. */
1044#define PSA_EXPORT_KEY_PAIR_OR_PUBLIC_MAX_SIZE \
1045 PSA_EXPORT_ASYMMETRIC_KEY_MAX_SIZE
1046
1047/** Sufficient output buffer size for psa_raw_key_agreement().
1048 *
1049 * This macro returns a compile-time constant if its arguments are
1050 * compile-time constants.
1051 *
1052 * \warning This macro may evaluate its arguments multiple times or
1053 * zero times, so you should not pass arguments that contain
1054 * side effects.
1055 *
1056 * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE.
1057 *
1058 * \param key_type A supported key type.
1059 * \param key_bits The size of the key in bits.
1060 *
1061 * \return If the parameters are valid and supported, return
1062 * a buffer size in bytes that guarantees that
1063 * psa_raw_key_agreement() will not fail with
1064 * #PSA_ERROR_BUFFER_TOO_SMALL.
1065 * If the parameters are a valid combination that
1066 * is not supported, return either a sensible size or 0.
1067 * If the parameters are not valid,
1068 * the return value is unspecified.
1069 */
1070#define PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(key_type, key_bits) \
1071 ((PSA_KEY_TYPE_IS_ECC_KEY_PAIR(key_type) || \
1072 PSA_KEY_TYPE_IS_DH_KEY_PAIR(key_type)) ? PSA_BITS_TO_BYTES(key_bits) : 0u)
1073
1074/** Maximum size of the output from psa_raw_key_agreement().
1075 *
1076 * This macro expands to a compile-time constant integer. This value is the
1077 * maximum size of the output any raw key agreement algorithm, in bytes.
1078 *
1079 * See also #PSA_RAW_KEY_AGREEMENT_OUTPUT_SIZE(\p key_type, \p key_bits).
1080 */
1081#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE 1
1082
1083#if defined(PSA_WANT_ALG_ECDH) && \
1084 (PSA_BITS_TO_BYTES(PSA_VENDOR_ECC_MAX_CURVE_BITS) > PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE)
1085#undef PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE
1086#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_ECC_MAX_CURVE_BITS)
1087#endif
1088#if defined(PSA_WANT_ALG_FFDH) && \
1089 (PSA_BITS_TO_BYTES(PSA_VENDOR_FFDH_MAX_KEY_BITS) > PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE)
1090#undef PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE
1091#define PSA_RAW_KEY_AGREEMENT_OUTPUT_MAX_SIZE PSA_BITS_TO_BYTES(PSA_VENDOR_FFDH_MAX_KEY_BITS)
1092#endif
1093
1094/** Maximum key length for ciphers.
1095 *
1096 * Since there is no additional PSA_WANT_xxx symbol to specifiy the size of
1097 * the key once a cipher is enabled (as it happens for asymmetric keys for
1098 * example), the maximum key length is taken into account for each cipher.
1099 * The resulting value will be the maximum cipher's key length given depending
1100 * on which ciphers are enabled.
1101 *
1102 * Note: max value for AES used below would be doubled if XTS were enabled, but
1103 * this mode is currently not supported in Mbed TLS implementation of PSA
1104 * APIs.
1105 */
1106#if (defined(PSA_WANT_KEY_TYPE_AES) || defined(PSA_WANT_KEY_TYPE_ARIA) || \
1107 defined(PSA_WANT_KEY_TYPE_CAMELLIA) || defined(PSA_WANT_KEY_TYPE_CHACHA20))
1108#define PSA_CIPHER_MAX_KEY_LENGTH 32u
1109#elif defined(PSA_WANT_KEY_TYPE_DES)
1110#define PSA_CIPHER_MAX_KEY_LENGTH 24u
1111#else
1112#define PSA_CIPHER_MAX_KEY_LENGTH 0u
1113#endif
1114
1115/** The default IV size for a cipher algorithm, in bytes.
1116 *
1117 * The IV that is generated as part of a call to #psa_cipher_encrypt() is always
1118 * the default IV length for the algorithm.
1119 *
1120 * This macro can be used to allocate a buffer of sufficient size to
1121 * store the IV output from #psa_cipher_generate_iv() when using
1122 * a multi-part cipher operation.
1123 *
1124 * See also #PSA_CIPHER_IV_MAX_SIZE.
1125 *
1126 * \warning This macro may evaluate its arguments multiple times or
1127 * zero times, so you should not pass arguments that contain
1128 * side effects.
1129 *
1130 * \param key_type A symmetric key type that is compatible with algorithm \p alg.
1131 *
1132 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that #PSA_ALG_IS_CIPHER(\p alg) is true).
1133 *
1134 * \return The default IV size for the specified key type and algorithm.
1135 * If the algorithm does not use an IV, return 0.
1136 * If the key type or cipher algorithm is not recognized,
1137 * or the parameters are incompatible, return 0.
1138 */
1139#define PSA_CIPHER_IV_LENGTH(key_type, alg) \
1140 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) > 1 && \
1141 ((alg) == PSA_ALG_CTR || \
1142 (alg) == PSA_ALG_CFB || \
1143 (alg) == PSA_ALG_OFB || \
1144 (alg) == PSA_ALG_XTS || \
1145 (alg) == PSA_ALG_CBC_NO_PADDING || \
1146 (alg) == PSA_ALG_CBC_PKCS7) ? PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \
1147 (key_type) == PSA_KEY_TYPE_CHACHA20 && \
1148 (alg) == PSA_ALG_STREAM_CIPHER ? 12u : \
1149 (alg) == PSA_ALG_CCM_STAR_NO_TAG ? 13u : \
1150 0u)
1151
1152/** The maximum IV size for all supported cipher algorithms, in bytes.
1153 *
1154 * See also #PSA_CIPHER_IV_LENGTH().
1155 */
1156#define PSA_CIPHER_IV_MAX_SIZE 16u
1157
1158/** The maximum size of the output of psa_cipher_encrypt(), in bytes.
1159 *
1160 * If the size of the output buffer is at least this large, it is guaranteed
1161 * that psa_cipher_encrypt() will not fail due to an insufficient buffer size.
1162 * Depending on the algorithm, the actual size of the output might be smaller.
1163 *
1164 * See also #PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(\p input_length).
1165 *
1166 * \warning This macro may evaluate its arguments multiple times or
1167 * zero times, so you should not pass arguments that contain
1168 * side effects.
1169 *
1170 * \param key_type A symmetric key type that is compatible with algorithm
1171 * alg.
1172 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that
1173 * #PSA_ALG_IS_CIPHER(\p alg) is true).
1174 * \param input_length Size of the input in bytes.
1175 *
1176 * \return A sufficient output size for the specified key type and
1177 * algorithm. If the key type or cipher algorithm is not
1178 * recognized, or the parameters are incompatible,
1179 * return 0.
1180 */
1181#define PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(key_type, alg, input_length) \
1182 (alg == PSA_ALG_CBC_PKCS7 ? \
1183 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) != 0 ? \
1184 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \
1185 (input_length) + 1u) + \
1186 PSA_CIPHER_IV_LENGTH((key_type), (alg)) : 0u) : \
1187 (PSA_ALG_IS_CIPHER(alg) ? \
1188 (input_length) + PSA_CIPHER_IV_LENGTH((key_type), (alg)) : \
1189 0u))
1190
1191/** A sufficient output buffer size for psa_cipher_encrypt(), for any of the
1192 * supported key types and cipher algorithms.
1193 *
1194 * If the size of the output buffer is at least this large, it is guaranteed
1195 * that psa_cipher_encrypt() will not fail due to an insufficient buffer size.
1196 *
1197 * See also #PSA_CIPHER_ENCRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length).
1198 *
1199 * \param input_length Size of the input in bytes.
1200 *
1201 */
1202#define PSA_CIPHER_ENCRYPT_OUTPUT_MAX_SIZE(input_length) \
1203 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, \
1204 (input_length) + 1u) + \
1205 PSA_CIPHER_IV_MAX_SIZE)
1206
1207/** The maximum size of the output of psa_cipher_decrypt(), in bytes.
1208 *
1209 * If the size of the output buffer is at least this large, it is guaranteed
1210 * that psa_cipher_decrypt() will not fail due to an insufficient buffer size.
1211 * Depending on the algorithm, the actual size of the output might be smaller.
1212 *
1213 * See also #PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(\p input_length).
1214 *
1215 * \param key_type A symmetric key type that is compatible with algorithm
1216 * alg.
1217 * \param alg A cipher algorithm (\c PSA_ALG_XXX value such that
1218 * #PSA_ALG_IS_CIPHER(\p alg) is true).
1219 * \param input_length Size of the input in bytes.
1220 *
1221 * \return A sufficient output size for the specified key type and
1222 * algorithm. If the key type or cipher algorithm is not
1223 * recognized, or the parameters are incompatible,
1224 * return 0.
1225 */
1226#define PSA_CIPHER_DECRYPT_OUTPUT_SIZE(key_type, alg, input_length) \
1227 (PSA_ALG_IS_CIPHER(alg) && \
1228 ((key_type) & PSA_KEY_TYPE_CATEGORY_MASK) == PSA_KEY_TYPE_CATEGORY_SYMMETRIC ? \
1229 (input_length) : \
1230 0u)
1231
1232/** A sufficient output buffer size for psa_cipher_decrypt(), for any of the
1233 * supported key types and cipher algorithms.
1234 *
1235 * If the size of the output buffer is at least this large, it is guaranteed
1236 * that psa_cipher_decrypt() will not fail due to an insufficient buffer size.
1237 *
1238 * See also #PSA_CIPHER_DECRYPT_OUTPUT_SIZE(\p key_type, \p alg, \p input_length).
1239 *
1240 * \param input_length Size of the input in bytes.
1241 */
1242#define PSA_CIPHER_DECRYPT_OUTPUT_MAX_SIZE(input_length) \
1243 (input_length)
1244
1245/** A sufficient output buffer size for psa_cipher_update().
1246 *
1247 * If the size of the output buffer is at least this large, it is guaranteed
1248 * that psa_cipher_update() will not fail due to an insufficient buffer size.
1249 * The actual size of the output might be smaller in any given call.
1250 *
1251 * See also #PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(\p input_length).
1252 *
1253 * \param key_type A symmetric key type that is compatible with algorithm
1254 * alg.
1255 * \param alg A cipher algorithm (PSA_ALG_XXX value such that
1256 * #PSA_ALG_IS_CIPHER(\p alg) is true).
1257 * \param input_length Size of the input in bytes.
1258 *
1259 * \return A sufficient output size for the specified key type and
1260 * algorithm. If the key type or cipher algorithm is not
1261 * recognized, or the parameters are incompatible, return 0.
1262 */
1263#define PSA_CIPHER_UPDATE_OUTPUT_SIZE(key_type, alg, input_length) \
1264 (PSA_ALG_IS_CIPHER(alg) ? \
1265 (PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) != 0 ? \
1266 (((alg) == PSA_ALG_CBC_PKCS7 || \
1267 (alg) == PSA_ALG_CBC_NO_PADDING || \
1268 (alg) == PSA_ALG_ECB_NO_PADDING) ? \
1269 PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type), \
1270 input_length) : \
1271 (input_length)) : 0u) : \
1272 0u)
1273
1274/** A sufficient output buffer size for psa_cipher_update(), for any of the
1275 * supported key types and cipher algorithms.
1276 *
1277 * If the size of the output buffer is at least this large, it is guaranteed
1278 * that psa_cipher_update() will not fail due to an insufficient buffer size.
1279 *
1280 * See also #PSA_CIPHER_UPDATE_OUTPUT_SIZE(\p key_type, \p alg, \p input_length).
1281 *
1282 * \param input_length Size of the input in bytes.
1283 */
1284#define PSA_CIPHER_UPDATE_OUTPUT_MAX_SIZE(input_length) \
1285 (PSA_ROUND_UP_TO_MULTIPLE(PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE, input_length))
1286
1287/** A sufficient ciphertext buffer size for psa_cipher_finish().
1288 *
1289 * If the size of the ciphertext buffer is at least this large, it is
1290 * guaranteed that psa_cipher_finish() will not fail due to an insufficient
1291 * ciphertext buffer size. The actual size of the output might be smaller in
1292 * any given call.
1293 *
1294 * See also #PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE().
1295 *
1296 * \param key_type A symmetric key type that is compatible with algorithm
1297 * alg.
1298 * \param alg A cipher algorithm (PSA_ALG_XXX value such that
1299 * #PSA_ALG_IS_CIPHER(\p alg) is true).
1300 * \return A sufficient output size for the specified key type and
1301 * algorithm. If the key type or cipher algorithm is not
1302 * recognized, or the parameters are incompatible, return 0.
1303 */
1304#define PSA_CIPHER_FINISH_OUTPUT_SIZE(key_type, alg) \
1305 (PSA_ALG_IS_CIPHER(alg) ? \
1306 (alg == PSA_ALG_CBC_PKCS7 ? \
1307 PSA_BLOCK_CIPHER_BLOCK_LENGTH(key_type) : \
1308 0u) : \
1309 0u)
1310
1311/** A sufficient ciphertext buffer size for psa_cipher_finish(), for any of the
1312 * supported key types and cipher algorithms.
1313 *
1314 * See also #PSA_CIPHER_FINISH_OUTPUT_SIZE(\p key_type, \p alg).
1315 */
1316#define PSA_CIPHER_FINISH_OUTPUT_MAX_SIZE \
1317 (PSA_BLOCK_CIPHER_BLOCK_MAX_SIZE)
1318
1319#endif /* PSA_CRYPTO_SIZES_H */
1320