package ed25519
|
|
|
|
import (
|
|
"bytes"
|
|
"crypto/subtle"
|
|
"fmt"
|
|
"io"
|
|
|
|
amino "github.com/tendermint/go-amino"
|
|
"golang.org/x/crypto/ed25519"
|
|
|
|
"github.com/tendermint/tendermint/crypto"
|
|
"github.com/tendermint/tendermint/crypto/tmhash"
|
|
)
|
|
|
|
//-------------------------------------
|
|
|
|
var _ crypto.PrivKey = PrivKeyEd25519{}
|
|
|
|
const (
|
|
PrivKeyAminoName = "tendermint/PrivKeyEd25519"
|
|
PubKeyAminoName = "tendermint/PubKeyEd25519"
|
|
// Size of an Edwards25519 signature. Namely the size of a compressed
|
|
// Edwards25519 point, and a field element. Both of which are 32 bytes.
|
|
SignatureSize = 64
|
|
)
|
|
|
|
var cdc = amino.NewCodec()
|
|
|
|
func init() {
|
|
cdc.RegisterInterface((*crypto.PubKey)(nil), nil)
|
|
cdc.RegisterConcrete(PubKeyEd25519{},
|
|
PubKeyAminoName, nil)
|
|
|
|
cdc.RegisterInterface((*crypto.PrivKey)(nil), nil)
|
|
cdc.RegisterConcrete(PrivKeyEd25519{},
|
|
PrivKeyAminoName, nil)
|
|
}
|
|
|
|
// PrivKeyEd25519 implements crypto.PrivKey.
|
|
type PrivKeyEd25519 [64]byte
|
|
|
|
// Bytes marshals the privkey using amino encoding.
|
|
func (privKey PrivKeyEd25519) Bytes() []byte {
|
|
return cdc.MustMarshalBinaryBare(privKey)
|
|
}
|
|
|
|
// Sign produces a signature on the provided message.
|
|
// This assumes the privkey is wellformed in the golang format.
|
|
// The first 32 bytes should be random,
|
|
// corresponding to the normal ed25519 private key.
|
|
// The latter 32 bytes should be the compressed public key.
|
|
// If these conditions aren't met, Sign will panic or produce an
|
|
// incorrect signature.
|
|
func (privKey PrivKeyEd25519) Sign(msg []byte) ([]byte, error) {
|
|
signatureBytes := ed25519.Sign(privKey[:], msg)
|
|
return signatureBytes, nil
|
|
}
|
|
|
|
// PubKey gets the corresponding public key from the private key.
|
|
func (privKey PrivKeyEd25519) PubKey() crypto.PubKey {
|
|
privKeyBytes := [64]byte(privKey)
|
|
initialized := false
|
|
// If the latter 32 bytes of the privkey are all zero, compute the pubkey
|
|
// otherwise privkey is initialized and we can use the cached value inside
|
|
// of the private key.
|
|
for _, v := range privKeyBytes[32:] {
|
|
if v != 0 {
|
|
initialized = true
|
|
break
|
|
}
|
|
}
|
|
|
|
if !initialized {
|
|
panic("Expected PrivKeyEd25519 to include concatenated pubkey bytes")
|
|
}
|
|
|
|
var pubkeyBytes [PubKeyEd25519Size]byte
|
|
copy(pubkeyBytes[:], privKeyBytes[32:])
|
|
return PubKeyEd25519(pubkeyBytes)
|
|
}
|
|
|
|
// Equals - you probably don't need to use this.
|
|
// Runs in constant time based on length of the keys.
|
|
func (privKey PrivKeyEd25519) Equals(other crypto.PrivKey) bool {
|
|
if otherEd, ok := other.(PrivKeyEd25519); ok {
|
|
return subtle.ConstantTimeCompare(privKey[:], otherEd[:]) == 1
|
|
}
|
|
|
|
return false
|
|
}
|
|
|
|
// GenPrivKey generates a new ed25519 private key.
|
|
// It uses OS randomness in conjunction with the current global random seed
|
|
// in tendermint/libs/common to generate the private key.
|
|
func GenPrivKey() PrivKeyEd25519 {
|
|
return genPrivKey(crypto.CReader())
|
|
}
|
|
|
|
// genPrivKey generates a new ed25519 private key using the provided reader.
|
|
func genPrivKey(rand io.Reader) PrivKeyEd25519 {
|
|
seed := make([]byte, 32)
|
|
_, err := io.ReadFull(rand, seed)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
|
|
privKey := ed25519.NewKeyFromSeed(seed)
|
|
var privKeyEd PrivKeyEd25519
|
|
copy(privKeyEd[:], privKey)
|
|
return privKeyEd
|
|
}
|
|
|
|
// GenPrivKeyFromSecret hashes the secret with SHA2, and uses
|
|
// that 32 byte output to create the private key.
|
|
// NOTE: secret should be the output of a KDF like bcrypt,
|
|
// if it's derived from user input.
|
|
func GenPrivKeyFromSecret(secret []byte) PrivKeyEd25519 {
|
|
seed := crypto.Sha256(secret) // Not Ripemd160 because we want 32 bytes.
|
|
|
|
privKey := ed25519.NewKeyFromSeed(seed)
|
|
var privKeyEd PrivKeyEd25519
|
|
copy(privKeyEd[:], privKey)
|
|
return privKeyEd
|
|
}
|
|
|
|
//-------------------------------------
|
|
|
|
var _ crypto.PubKey = PubKeyEd25519{}
|
|
|
|
// PubKeyEd25519Size is the number of bytes in an Ed25519 signature.
|
|
const PubKeyEd25519Size = 32
|
|
|
|
// PubKeyEd25519 implements crypto.PubKey for the Ed25519 signature scheme.
|
|
type PubKeyEd25519 [PubKeyEd25519Size]byte
|
|
|
|
// Address is the SHA256-20 of the raw pubkey bytes.
|
|
func (pubKey PubKeyEd25519) Address() crypto.Address {
|
|
return crypto.Address(tmhash.SumTruncated(pubKey[:]))
|
|
}
|
|
|
|
// Bytes marshals the PubKey using amino encoding.
|
|
func (pubKey PubKeyEd25519) Bytes() []byte {
|
|
bz, err := cdc.MarshalBinaryBare(pubKey)
|
|
if err != nil {
|
|
panic(err)
|
|
}
|
|
return bz
|
|
}
|
|
|
|
func (pubKey PubKeyEd25519) VerifyBytes(msg []byte, sig []byte) bool {
|
|
// make sure we use the same algorithm to sign
|
|
if len(sig) != SignatureSize {
|
|
return false
|
|
}
|
|
return ed25519.Verify(pubKey[:], msg, sig)
|
|
}
|
|
|
|
func (pubKey PubKeyEd25519) String() string {
|
|
return fmt.Sprintf("PubKeyEd25519{%X}", pubKey[:])
|
|
}
|
|
|
|
// nolint: golint
|
|
func (pubKey PubKeyEd25519) Equals(other crypto.PubKey) bool {
|
|
if otherEd, ok := other.(PubKeyEd25519); ok {
|
|
return bytes.Equal(pubKey[:], otherEd[:])
|
|
}
|
|
|
|
return false
|
|
}
|