Make psa_calculate_key_bits return psa_key_bits_t
This is cleaner and solves a complaint from MSVC about truncation from
size_t to psa_key_bits_t.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 3f5f371..cbe3261 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -714,20 +714,24 @@
*
* \return The key size in bits, calculated from the key data.
*/
-static size_t psa_calculate_key_bits( const psa_key_slot_t *slot )
+static psa_key_bits_t psa_calculate_key_bits( const psa_key_slot_t *slot )
{
+ size_t bits = 0; /* return 0 on an empty slot */
+
if( key_type_is_raw_bytes( slot->attr.type ) )
- return( slot->data.raw.bytes * 8 );
+ bits = PSA_BYTES_TO_BITS( slot->data.raw.bytes );
#if defined(MBEDTLS_RSA_C)
- if( PSA_KEY_TYPE_IS_RSA( slot->attr.type ) )
- return( PSA_BYTES_TO_BITS( mbedtls_rsa_get_len( slot->data.rsa ) ) );
+ else if( PSA_KEY_TYPE_IS_RSA( slot->attr.type ) )
+ bits = PSA_BYTES_TO_BITS( mbedtls_rsa_get_len( slot->data.rsa ) );
#endif /* defined(MBEDTLS_RSA_C) */
#if defined(MBEDTLS_ECP_C)
- if( PSA_KEY_TYPE_IS_ECC( slot->attr.type ) )
- return( slot->data.ecp->grp.pbits );
+ else if( PSA_KEY_TYPE_IS_ECC( slot->attr.type ) )
+ bits = slot->data.ecp->grp.pbits;
#endif /* defined(MBEDTLS_ECP_C) */
- /* Shouldn't happen except on an empty slot. */
- return( 0 );
+
+ /* We know that the size fits in psa_key_bits_t thanks to checks
+ * when the key was created. */
+ return( (psa_key_bits_t) bits );
}
/** Import key data into a slot. `slot->attr.type` must have been set