packer/vendor/github.com/stretchr/objx/security.go

package objx

import (
	"crypto/sha1"
	"encoding/hex"
)

// HashWithKey hashes the specified string using the security
// key.
func HashWithKey(data, key string) string {
	hash := sha1.New()
	_, err := hash.Write([]byte(data + ":" + key))
	if err != nil {
		return ""
	}
	return hex.EncodeToString(hash.Sum(nil))
}