laconicd/crypto/algorithm.go
Federico Kunze a243f43fe2
crypto: add keyring supported algorithms (#439)
* add keyring supported algorithms

* lint

* minor updates

* use eth_secp256k1 as the default signing algo

* add flag

* derivation func

* refactor

* rename keys amino registration

* fix keys

* address comments from review
2020-08-11 11:01:15 -04:00

85 lines
2.2 KiB
Go

package crypto
import (
"fmt"
"github.com/pkg/errors"
"crypto/hmac"
"crypto/sha512"
"github.com/tyler-smith/go-bip39"
ethcrypto "github.com/ethereum/go-ethereum/crypto"
tmcrypto "github.com/tendermint/tendermint/crypto"
"github.com/cosmos/cosmos-sdk/crypto/keyring"
)
const (
// EthSecp256k1 defines the ECDSA secp256k1 used on Ethereum
EthSecp256k1 = keyring.SigningAlgo("eth_secp256k1")
)
// SupportedAlgorithms defines the list of signing algorithms used on Ethermint:
// - eth_secp256k1 (Ethereum)
// - secp256k1 (Tendermint)
var SupportedAlgorithms = []keyring.SigningAlgo{EthSecp256k1, keyring.Secp256k1}
// EthSecp256k1Options defines a keyring options for the ethereum Secp256k1 curve.
func EthSecp256k1Options() []keyring.KeybaseOption {
return []keyring.KeybaseOption{
keyring.WithKeygenFunc(EthermintKeygenFunc),
keyring.WithDeriveFunc(DeriveKey),
keyring.WithSupportedAlgos(SupportedAlgorithms),
keyring.WithSupportedAlgosLedger(SupportedAlgorithms),
}
}
func DeriveKey(mnemonic, bip39Passphrase, hdPath string, algo keyring.SigningAlgo) ([]byte, error) {
switch algo {
case keyring.Secp256k1:
return keyring.StdDeriveKey(mnemonic, bip39Passphrase, hdPath, algo)
case EthSecp256k1:
return DeriveSecp256k1(mnemonic, bip39Passphrase, hdPath)
default:
return nil, errors.Wrap(keyring.ErrUnsupportedSigningAlgo, string(algo))
}
}
// EthermintKeygenFunc is the key generation function to generate secp256k1 ToECDSA
// from ethereum.
func EthermintKeygenFunc(bz []byte, algo keyring.SigningAlgo) (tmcrypto.PrivKey, error) {
if algo != EthSecp256k1 {
return nil, fmt.Errorf("signing algorithm must be %s, got %s", EthSecp256k1, algo)
}
return PrivKeySecp256k1(bz), nil
}
func DeriveSecp256k1(mnemonic, bip39Passphrase, _ string) ([]byte, error) {
seed, err := bip39.NewSeedWithErrorChecking(mnemonic, bip39Passphrase)
if err != nil {
return nil, err
}
// HMAC the seed to produce the private key and chain code
mac := hmac.New(sha512.New, []byte("Bitcoin seed"))
_, err = mac.Write(seed)
if err != nil {
return nil, err
}
seed = mac.Sum(nil)
priv, err := ethcrypto.ToECDSA(seed[:32])
if err != nil {
return nil, err
}
derivedKey := PrivKeySecp256k1(ethcrypto.FromECDSA(priv))
return derivedKey, nil
}