neoneo-go/pkg/crypto/hash/hash.go
Roman Khimov df12adaa9e crypto: remove crypto.Verifiable interface
We can now verify any hash.Hashable thing.
2021-03-26 13:45:18 +03:00

74 lines
1.8 KiB
Go

package hash
import (
"crypto/sha256"
"encoding/binary"
"github.com/nspcc-dev/neo-go/pkg/util"
"golang.org/x/crypto/ripemd160"
)
// Hashable represents an object which can be hashed. Usually these objects
// are io.Serializable and signable. They tend to cache the hash inside for
// effectiveness, providing this accessor method. Anything that can be
// identified with a hash can then be signed and verified.
type Hashable interface {
Hash() util.Uint256
}
func getSignedData(net uint32, hh Hashable) []byte {
var b = make([]byte, 4+32)
binary.LittleEndian.PutUint32(b, net)
h := hh.Hash()
copy(b[4:], h[:])
return b
}
// NetSha256 calculates network-specific hash of Hashable item that can then
// be signed/verified.
func NetSha256(net uint32, hh Hashable) util.Uint256 {
return Sha256(getSignedData(net, hh))
}
// Sha256 hashes the incoming byte slice
// using the sha256 algorithm.
func Sha256(data []byte) util.Uint256 {
hash := sha256.Sum256(data)
return hash
}
// DoubleSha256 performs sha256 twice on the given data.
func DoubleSha256(data []byte) util.Uint256 {
var hash util.Uint256
h1 := Sha256(data)
hash = Sha256(h1.BytesBE())
return hash
}
// RipeMD160 performs the RIPEMD160 hash algorithm
// on the given data.
func RipeMD160(data []byte) util.Uint160 {
var hash util.Uint160
hasher := ripemd160.New()
_, _ = hasher.Write(data)
hash, _ = util.Uint160DecodeBytesBE(hasher.Sum(nil))
return hash
}
// Hash160 performs sha256 and then ripemd160
// on the given data.
func Hash160(data []byte) util.Uint160 {
h1 := Sha256(data)
h2 := RipeMD160(h1.BytesBE())
return h2
}
// Checksum returns the checksum for a given piece of data
// using sha256 twice as the hash algorithm.
func Checksum(data []byte) []byte {
hash := DoubleSha256(data)
return hash[:4]
}