Change the encoding of EC curves and DH groups to include the size
Change the representation of psa_ecc_curve_t and psa_dh_group_t from
the IETF 16-bit encoding to a custom 24-bit encoding where the upper 8
bits represent a curve family and the lower 16 bits are the key size
in bits. Families are based on naming and mathematical similarity,
with sufficiently precise families that no two curves in a family have
the same bit size (for example SECP-R1 and SECP-R2 are two different
families).
As a consequence, the lower 16 bits of a key type value are always
either the key size or 0.
diff --git a/library/psa_crypto.c b/library/psa_crypto.c
index 79db686..1120c83 100644
--- a/library/psa_crypto.c
+++ b/library/psa_crypto.c
@@ -427,7 +427,8 @@
mbedtls_ecp_group_id mbedtls_ecc_group_of_psa( psa_ecc_curve_t curve,
size_t byte_length )
{
- (void) byte_length;
+ if( PSA_BITS_TO_BYTES( curve & 0xffff ) != byte_length )
+ return( MBEDTLS_ECP_DP_NONE );
switch( curve )
{
case PSA_ECC_CURVE_SECP192R1: