Add AEAD tag length parameter to mbedtls_psa_translate_cipher_mode()

In case of AEAD ciphers, the cipher mode (and not even the entire content
of mbedtls_cipher_info_t) doesn't uniquely determine a psa_algorithm_t
because it doesn't specify the AEAD tag length, which however is included
in psa_algorithm_t identifiers.

This commit adds a tag length value to mbedtls_psa_translate_cipher_mode()
to account for that ambiguity.
This commit is contained in:
Hanno Becker 2018-11-15 15:48:57 +00:00
parent 14f78b03bb
commit dec64735e2

View file

@ -93,16 +93,18 @@ static inline psa_key_type_t mbedtls_psa_translate_cipher_type(
}
static inline psa_algorithm_t mbedtls_psa_translate_cipher_mode(
mbedtls_cipher_mode_t mode )
mbedtls_cipher_mode_t mode, size_t taglen )
{
switch( mode )
{
case MBEDTLS_MODE_GCM:
return( PSA_ALG_GCM );
return( PSA_ALG_AEAD_WITH_TAG_LENGTH( PSA_ALG_GCM, taglen ) );
case MBEDTLS_MODE_CCM:
return( PSA_ALG_CCM );
return( PSA_ALG_AEAD_WITH_TAG_LENGTH( PSA_ALG_CCM, taglen ) );
case MBEDTLS_MODE_CBC:
if( taglen == 0 )
return( PSA_ALG_CBC_NO_PADDING );
/* Intentional fallthrough for taglen != 0 */
default:
return( 0 );
}