You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: crc64.go
    path of file: ./repos/gccrs/libgo/go/hash/crc64
    
    the code of the file until where you have to start completion: // Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// Package crc64 implements the 64-bit cyclic redundancy check, or CRC-64,
// checksum. See https://en.wikipedia.org/wiki/Cyclic_redundancy_check for
// information.
package crc64

import (
	"errors"
	"hash"
	"
    
func (d *digest) UnmarshalBinary(b []byte) error {
	if len(b) < len(magic) || string(b[:len(magic)]) != magic {
		return errors.New("hash/crc64: invalid hash state identifier")
	}
	if len(b) != marshaledSize {
		return errors.New("hash/crc64: invalid hash state size")
	}
	if tableSum(d.tab) != readUint64(b[4:]) {
		return errors.New("hash/crc64: tables do not match")
	}
	d.crc = readUint64(b[12:])
	return nil
}