Wrong encoding of CKA_EC_POINT for Edwards curve kyes using OpenSSL #824
Description
When exporting a public key that was generated using softhsm, the output data of the attribute CKA_EC_POINT is 34 Bytes instead of 32 Bytes,
The first two bytes seem to correspond to the encoding used for DER encoded OCTET STRING. The pkcs11 spec states:
| Attribute | Data type | Meaning |
|---|---|---|
| CKA_EC_PARAMS1,3 | Byte array | DER-encoding of a Parameters value as defined above |
| CKA_EC_POINT1,4 | Byte array | DER-encoding of the b-bit public key value in little endian order as defined in RFC 8032 |
RFC 8032 does not mention a DER encoded OCTET STRING but uses the wording octet string to mean a string of octets.
Furthermore, softhsm does not validate the attribute when creating a public key with C_CreateObject. Only when using the key to verify a signature, the verification fails.