162 lines
4.1 KiB
Go
162 lines
4.1 KiB
Go
// Copyright 2018 The go-ethereum Authors
|
|
// This file is part of the go-ethereum library.
|
|
//
|
|
// The go-ethereum library is free software: you can redistribute it and/or modify
|
|
// it under the terms of the GNU Lesser General Public License as published by
|
|
// the Free Software Foundation, either version 3 of the License, or
|
|
// (at your option) any later version.
|
|
//
|
|
// The go-ethereum library is distributed in the hope that it will be useful,
|
|
// but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
// GNU Lesser General Public License for more details.
|
|
//
|
|
// You should have received a copy of the GNU Lesser General Public License
|
|
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
|
|
|
|
package enode
|
|
|
|
import (
|
|
"crypto/ecdsa"
|
|
"fmt"
|
|
"io"
|
|
|
|
"github.com/ethereum/go-ethereum/common/math"
|
|
"github.com/ethereum/go-ethereum/crypto"
|
|
"github.com/ethereum/go-ethereum/p2p/enr"
|
|
"github.com/ethereum/go-ethereum/rlp"
|
|
"golang.org/x/crypto/sha3"
|
|
)
|
|
|
|
// ValidSchemes is a List of known secure identity schemes.
|
|
var ValidSchemes = enr.SchemeMap{
|
|
"v4": V4ID{},
|
|
}
|
|
|
|
// ValidSchemesForTesting is a List of identity schemes for testing.
|
|
var ValidSchemesForTesting = enr.SchemeMap{
|
|
"v4": V4ID{},
|
|
"null": NullID{},
|
|
}
|
|
|
|
// V4ID is the "v4" identity scheme.
|
|
type V4ID struct{}
|
|
|
|
// SignV4 signs a record using the v4 scheme.
|
|
func SignV4(r *enr.Record, privkey *ecdsa.PrivateKey) error {
|
|
// Copy r to avoid modifying it if signing fails.
|
|
cpy := *r
|
|
cpy.Set(enr.ID("v4"))
|
|
cpy.Set(Secp256k1(privkey.PublicKey))
|
|
|
|
h := sha3.NewLegacyKeccak256()
|
|
rlp.Encode(h, cpy.AppendElements(nil))
|
|
sig, err := crypto.Sign(h.Sum(nil), privkey)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
sig = sig[:len(sig)-1] // remove v
|
|
if err = cpy.SetSig(V4ID{}, sig); err == nil {
|
|
*r = cpy
|
|
}
|
|
return err
|
|
}
|
|
|
|
func (V4ID) Verify(r *enr.Record, sig []byte) error {
|
|
var entry s256raw
|
|
if err := r.Load(&entry); err != nil {
|
|
return err
|
|
} else if len(entry) != 33 {
|
|
return fmt.Errorf("invalid public key")
|
|
}
|
|
|
|
h := sha3.NewLegacyKeccak256()
|
|
rlp.Encode(h, r.AppendElements(nil))
|
|
if !crypto.VerifySignature(entry, h.Sum(nil), sig) {
|
|
return enr.ErrInvalidSig
|
|
}
|
|
return nil
|
|
}
|
|
|
|
func (V4ID) NodeAddr(r *enr.Record) []byte {
|
|
var pubkey Secp256k1
|
|
err := r.Load(&pubkey)
|
|
if err != nil {
|
|
return nil
|
|
}
|
|
buf := make([]byte, 64)
|
|
math.ReadBits(pubkey.X, buf[:32])
|
|
math.ReadBits(pubkey.Y, buf[32:])
|
|
return crypto.Keccak256(buf)
|
|
}
|
|
|
|
// Secp256k1 is the "secp256k1" key, which holds a public key.
|
|
type Secp256k1 ecdsa.PublicKey
|
|
|
|
func (v Secp256k1) ENRKey() string { return "secp256k1" }
|
|
|
|
// EncodeRLP implements rlp.Encoder.
|
|
func (v Secp256k1) EncodeRLP(w io.Writer) error {
|
|
return rlp.Encode(w, crypto.CompressPubkey((*ecdsa.PublicKey)(&v)))
|
|
}
|
|
|
|
// DecodeRLP implements rlp.Decoder.
|
|
func (v *Secp256k1) DecodeRLP(s *rlp.Stream) error {
|
|
buf, err := s.Bytes()
|
|
if err != nil {
|
|
return err
|
|
}
|
|
pk, err := crypto.DecompressPubkey(buf)
|
|
if err != nil {
|
|
return err
|
|
}
|
|
*v = (Secp256k1)(*pk)
|
|
return nil
|
|
}
|
|
|
|
// s256raw is an unparsed secp256k1 public key entry.
|
|
type s256raw []byte
|
|
|
|
func (s256raw) ENRKey() string { return "secp256k1" }
|
|
|
|
// v4CompatID is a weaker and insecure version of the "v4" scheme which only checks for the
|
|
// presence of a secp256k1 public key, but doesn't verify the signature.
|
|
type v4CompatID struct {
|
|
V4ID
|
|
}
|
|
|
|
func (v4CompatID) Verify(r *enr.Record, sig []byte) error {
|
|
var pubkey Secp256k1
|
|
return r.Load(&pubkey)
|
|
}
|
|
|
|
func signV4Compat(r *enr.Record, pubkey *ecdsa.PublicKey) {
|
|
r.Set((*Secp256k1)(pubkey))
|
|
if err := r.SetSig(v4CompatID{}, []byte{}); err != nil {
|
|
panic(err)
|
|
}
|
|
}
|
|
|
|
// NullID is the "null" ENR identity scheme. This scheme stores the node
|
|
// ID in the record without any signature.
|
|
type NullID struct{}
|
|
|
|
func (NullID) Verify(r *enr.Record, sig []byte) error {
|
|
return nil
|
|
}
|
|
|
|
func (NullID) NodeAddr(r *enr.Record) []byte {
|
|
var id ID
|
|
r.Load(enr.WithEntry("nulladdr", &id))
|
|
return id[:]
|
|
}
|
|
|
|
func SignNull(r *enr.Record, id ID) *Node {
|
|
r.Set(enr.ID("null"))
|
|
r.Set(enr.WithEntry("nulladdr", id))
|
|
if err := r.SetSig(NullID{}, []byte{}); err != nil {
|
|
panic(err)
|
|
}
|
|
return &Node{r: *r, id: id}
|
|
}
|