cheat/vendor/github.com/ProtonMail/go-crypto/openpgp/eddsa/eddsa.go

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// Package eddsa implements EdDSA signature, suitable for OpenPGP, as specified in
// https://datatracker.ietf.org/doc/html/draft-ietf-openpgp-crypto-refresh-06#section-13.7
package eddsa
import (
"errors"
"github.com/ProtonMail/go-crypto/openpgp/internal/ecc"
"io"
)
type PublicKey struct {
X []byte
curve ecc.EdDSACurve
}
type PrivateKey struct {
PublicKey
D []byte
}
func NewPublicKey(curve ecc.EdDSACurve) *PublicKey {
return &PublicKey{
curve: curve,
}
}
func NewPrivateKey(key PublicKey) *PrivateKey {
return &PrivateKey{
PublicKey: key,
}
}
func (pk *PublicKey) GetCurve() ecc.EdDSACurve {
return pk.curve
}
func (pk *PublicKey) MarshalPoint() []byte {
return pk.curve.MarshalBytePoint(pk.X)
}
func (pk *PublicKey) UnmarshalPoint(x []byte) error {
pk.X = pk.curve.UnmarshalBytePoint(x)
if pk.X == nil {
return errors.New("eddsa: failed to parse EC point")
}
return nil
}
func (sk *PrivateKey) MarshalByteSecret() []byte {
return sk.curve.MarshalByteSecret(sk.D)
}
func (sk *PrivateKey) UnmarshalByteSecret(d []byte) error {
sk.D = sk.curve.UnmarshalByteSecret(d)
if sk.D == nil {
return errors.New("eddsa: failed to parse scalar")
}
return nil
}
func GenerateKey(rand io.Reader, c ecc.EdDSACurve) (priv *PrivateKey, err error) {
priv = new(PrivateKey)
priv.PublicKey.curve = c
priv.PublicKey.X, priv.D, err = c.GenerateEdDSA(rand)
return
}
func Sign(priv *PrivateKey, message []byte) (r, s []byte, err error) {
sig, err := priv.PublicKey.curve.Sign(priv.PublicKey.X, priv.D, message)
if err != nil {
return nil, nil, err
}
r, s = priv.PublicKey.curve.MarshalSignature(sig)
return
}
func Verify(pub *PublicKey, message, r, s []byte) bool {
sig := pub.curve.UnmarshalSignature(r, s)
if sig == nil {
return false
}
return pub.curve.Verify(pub.X, message, sig)
}
func Validate(priv *PrivateKey) error {
return priv.curve.ValidateEdDSA(priv.PublicKey.X, priv.D)
}