FC_UnwrapKey - unwrap a key
CK_RV FC_UnwrapKey( CK_SESSION_HANDLE hSession, CK_MECHANISM_PTR pMechanism, CK_OBJECT_HANDLE hUnwrappingKey, CK_BYTE_PTR pWrappedKey, CK_ULONG usWrappedKeyLen, CK_ATTRIBUTE_PTR pTemplate, CK_ULONG usAttributeCount, CK_OBJECT_HANDLE_PTR phKey );
hSessionpMechanismhUnwrappingKeypWrappedKeyusWrappedKeyLenpTemplateusAttributeCountphKeyFC_UnwrapKey unwraps (decrypts) a key and creates a new key opbject. If pWrappedKey is NULL the length of the wrapped key is returned in pusWrappedKeyLen and FC_UnwrapKey may be called again with pWrappedKey set to retrieve the wrapped key.
A user must log into the token (to assume the NSS User role) before calling FC_UnwrapKey.