lbcd/privkey.go
Dave Collins 77c02f36ee Cleanup new code introduced by Pull Request #4.
- Keep comments to 80 cols for consistency with the rest of the code base
- Made verify a method off of Signature instead of PublicKey since one
  verifies a signature with a public key as opposed to the other way
  around
- Return new signature from Sign function directly rather than creating a
  local temporary variable
- Modify a couple of comments as recommended by @owainga
- Update sample usage in doc.go for both signing messages and verifying
  signatures

ok @owainga
2014-05-20 10:36:15 -05:00

49 lines
1.3 KiB
Go

// Copyright (c) 2013-2014 Conformal Systems LLC.
// Use of this source code is governed by an ISC
// license that can be found in the LICENSE file.
package btcec
import (
"crypto/ecdsa"
"crypto/rand"
"math/big"
)
// PrivateKey wraps an ecdsa.PrivateKey as a convenience mainly for signing
// things with the the private key without having to directly import the ecdsa
// package.
type PrivateKey ecdsa.PrivateKey
// PrivKeyFromBytes returns a private and public key for `curve' based on the
// private key passed as an argument as a byte slice.
func PrivKeyFromBytes(curve *KoblitzCurve, pk []byte) (*PrivateKey,
*PublicKey) {
x, y := curve.ScalarBaseMult(pk)
priv := &ecdsa.PrivateKey{
PublicKey: ecdsa.PublicKey{
Curve: curve,
X: x,
Y: y,
},
D: new(big.Int).SetBytes(pk),
}
return (*PrivateKey)(priv), (*PublicKey)(&priv.PublicKey)
}
// ToECDSA returns the private key as a *ecdsa.PrivateKey.
func (p *PrivateKey) ToECDSA() *ecdsa.PrivateKey {
return (*ecdsa.PrivateKey)(p)
}
// Sign wraps ecdsa.Sign to sign the provided hash (which should be the result
// of hashing a larger message) using the private key.
func (p *PrivateKey) Sign(hash []byte) (*Signature, error) {
r, s, err := ecdsa.Sign(rand.Reader, p.ToECDSA(), hash)
if err != nil {
return nil, err
}
return &Signature{R: r, S: s}, nil
}