example of using golang's sha512 for checksum

checksum.go

package main

import (
	"crypto/sha512"
	"fmt"
)

// CalcChecksum takes a slice of bytes and calculate it as a checksum
// it is using SHA512 for that (128 bytes for result)
func CalcChecksum(buff []byte) []byte {
	sha := sha512.New()
	sha.Write(buff)
	checksum := sha.Sum(nil)
	return checksum
}

func main() {
  // calc "a"
	calcHex := fmt.Sprintf("%x", CalcChecksum([]byte{97}))
	hex := "1f40fc92da241694750979ee6cf582f2d5d7d28e18335de05abc54d0560e0f5302860c652bf08d560252aa5e74210546f369fbbbce8c12cfc7957b2652fe9a75"

	fmt.Println(calcHex == hex, len(hex))
}