New macro PSA_AEAD_TAG_SIZE, use it for PSA_AEAD_xxx_OUTPUT_SIZE

This commit is contained in:
Gilles Peskine 2018-06-08 11:41:57 +02:00 committed by itayzafrir
parent 212e4d8f7c
commit 5e39dc96e0

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@ -1073,6 +1073,25 @@ psa_status_t psa_cipher_abort(psa_cipher_operation_t *operation);
* @{
*/
/** The tag size for an AEAD algorithm, in bytes.
*
* \param alg An AEAD algorithm
* (\c PSA_ALG_XXX value such that
* #PSA_ALG_IS_AEAD(alg) is true).
*
* \return The tag size for the specified algorithm.
* If the AEAD algorithm does not have an identified
* tag that can be distinguished from the rest of
* the ciphertext, return 0.
* If the AEAD algorithm is not recognized, return 0.
* An implementation may return either 0 or a
* correct size for an AEAD algorithm that it
* recognizes, but does not support.
*/
#define PSA_AEAD_TAG_SIZE(alg) \
((alg) == PSA_ALG_GCM ? 16 : \
(alg) == PSA_ALG_CCM ? 16 : \
0)
/** The maximum size of the output of psa_aead_encrypt(), in bytes.
*
@ -1094,8 +1113,8 @@ psa_status_t psa_cipher_abort(psa_cipher_operation_t *operation);
* recognizes, but does not support.
*/
#define PSA_AEAD_ENCRYPT_OUTPUT_SIZE(alg, plaintext_length) \
((alg) == PSA_ALG_GCM ? (plaintext_length) + 16 : \
(alg) == PSA_ALG_CCM ? (plaintext_length) + 16 : \
(PSA_AEAD_TAG_SIZE(alg) != 0 ? \
(plaintext_length) + PSA_AEAD_TAG_SIZE(alg) : \
0)
/** Process an authenticated encryption operation.
@ -1170,9 +1189,9 @@ psa_status_t psa_aead_encrypt( psa_key_slot_t key,
* correct size for an AEAD algorithm that it
* recognizes, but does not support.
*/
#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(alg, ciphertext_length) \
((alg) == PSA_ALG_GCM ? (ciphertext_length) - 16 : \
(alg) == PSA_ALG_CCM ? (ciphertext_length) - 16 : \
#define PSA_AEAD_DECRYPT_OUTPUT_SIZE(alg, ciphertext_length) \
(PSA_AEAD_TAG_SIZE(alg) != 0 ? \
(plaintext_length) - PSA_AEAD_TAG_SIZE(alg) : \
0)
/** Process an authenticated decryption operation.