case, // we copy signature (r), signature(s), hashed message, public key x component, // and public key y component into the parameter block. p := params[:0] p = appendBlock(p, blockSize, r) p = appendBlock(p, blockSize, s) p = appendBlock(p, blockSize, hashToBytes(c, hash)) p = appendBlock(p, blockSize, pub.q[1:1+len(pub.q)/2]) p = appendBlock(p, blockSize, pub.q[1+len(pub.q)/2:]) if kdsa(functionCode, &params) != 0 { return errors.New("invalid signature") } return nil } golang.org/fips140@v1.0.0-c...