Initial commit

.gitignore

@@ -0,0 +1 @@
+/.idea/

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2023 Base
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

go.mod

@@ -0,0 +1,24 @@
+module github.com/base-org/eip712sign
+
+go 1.19
+
+require (
+	github.com/decred/dcrd/hdkeychain/v3 v3.1.1
+	github.com/ethereum/go-ethereum v1.12.0
+	github.com/tyler-smith/go-bip39 v1.1.0
+)
+
+require (
+	github.com/btcsuite/btcd/btcec/v2 v2.2.0 // indirect
+	github.com/decred/base58 v1.0.5 // indirect
+	github.com/decred/dcrd/crypto/blake256 v1.0.1 // indirect
+	github.com/decred/dcrd/crypto/ripemd160 v1.0.2 // indirect
+	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.2.0 // indirect
+	github.com/go-stack/stack v1.8.1 // indirect
+	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/holiman/uint256 v1.2.2-0.20230321075855-87b91420868c // indirect
+	github.com/karalabe/usb v0.0.3-0.20230711191512-61db3e06439c // indirect
+	golang.org/x/crypto v0.1.0 // indirect
+	golang.org/x/sys v0.7.0 // indirect
+	google.golang.org/protobuf v1.28.1 // indirect
+)

go.sum

@@ -0,0 +1,89 @@
+github.com/DataDog/zstd v1.5.2 h1:vUG4lAyuPCXO0TLbXvPv7EB7cNK1QV/luu55UHLrrn8=
+github.com/StackExchange/wmi v0.0.0-20180116203802-5d049714c4a6 h1:fLjPD/aNc3UIOA6tDi6QXUemppXK3P9BI7mr2hd6gx8=
+github.com/VictoriaMetrics/fastcache v1.6.0 h1:C/3Oi3EiBCqufydp1neRZkqcwmEiuRT9c3fqvvgKm5o=
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main.go

@@ -0,0 +1,237 @@
+package main
+
+import (
+	"bytes"
+	"crypto/ecdsa"
+	"encoding/hex"
+	"flag"
+	"fmt"
+	"io"
+	"log"
+	"os"
+	"os/exec"
+	"strings"
+
+	"github.com/decred/dcrd/hdkeychain/v3"
+	"github.com/ethereum/go-ethereum/accounts"
+	"github.com/ethereum/go-ethereum/accounts/usbwallet"
+	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/tyler-smith/go-bip39"
+)
+
+func main() {
+	var privateKey string
+	var ledger bool
+	var mnemonic string
+	var hdPath string
+	var prefix string
+	var suffix string
+	var workdir string
+	flag.StringVar(&privateKey, "private-key", "", "Private key to use for signing")
+	flag.BoolVar(&ledger, "ledger", false, "Use ledger device for signing")
+	flag.StringVar(&mnemonic, "mnemonic", "", "Mnemonic to use for signing")
+	flag.StringVar(&hdPath, "hd-paths", "m/44'/60'/0'/0/0", "Hierarchical deterministic derivation path for mnemonic or ledger")
+	flag.StringVar(&prefix, "prefix", "vvvvvvvv", "String that prefixes the data to be signed")
+	flag.StringVar(&suffix, "suffix", "^^^^^^^^", "String that suffixes the data to be signed")
+	flag.StringVar(&workdir, "workdir", ".", "Directory in which to run the subprocess")
+	flag.Parse()
+
+	options := 0
+	if privateKey != "" {
+		options++
+	}
+	if ledger {
+		options++
+	}
+	if mnemonic != "" {
+		options++
+	}
+	if options != 1 {
+		log.Fatalf("One (and only one) of --private-key, --ledger, --mnemonic must be set")
+	}
+
+	var input []byte
+	var err error
+	if flag.NArg() == 0 {
+		input, err = io.ReadAll(os.Stdin)
+		if err != nil {
+			log.Fatalf("Error reading from stdin: %v", err)
+		}
+	} else {
+		input, err = run(workdir, flag.Arg(0), flag.Args()[1:]...)
+		if err != nil {
+			log.Fatalf("Error running process: %v", err)
+		}
+		fmt.Printf("\n%s exited with code 0\n", flag.Arg(0))
+	}
+
+	if index := strings.Index(string(input), prefix); prefix != "" && index >= 0 {
+		input = input[index+len(prefix):]
+	}
+	if index := strings.Index(string(input), suffix); suffix != "" && index >= 0 {
+		input = input[:index]
+	}
+
+	fmt.Println()
+	hash := common.FromHex(strings.TrimSpace(string(input)))
+	if len(hash) != 66 {
+		log.Fatalf("Expected EIP-712 hex string with 66 bytes, got %d bytes, value: %s", len(input), string(input))
+	}
+
+	s, err := createSigner(privateKey, mnemonic, hdPath)
+	if err != nil {
+		log.Fatalf("Error creating signer: %v", err)
+	}
+
+	domainHash := hash[2:34]
+	messageHash := hash[34:66]
+	fmt.Printf("Domain hash: 0x%s\n", hex.EncodeToString(domainHash))
+	fmt.Printf("Message hash: 0x%s\n", hex.EncodeToString(messageHash))
+
+	if ledger {
+		fmt.Printf("Data sent to ledger, awaiting signature...")
+	}
+	signature, err := s.sign(hash)
+	if ledger {
+		fmt.Println("done")
+	}
+	if err != nil {
+		log.Fatalf("Error signing data: %v", err)
+	}
+
+	fmt.Printf("\nData: 0x%s\n", hex.EncodeToString(hash))
+	fmt.Printf("Signer: %s\n", s.address().String())
+	fmt.Printf("Signature: %s\n", hex.EncodeToString(signature))
+}
+
+func run(workdir, name string, args ...string) ([]byte, error) {
+	cmd := exec.Command(name, args...)
+	cmd.Dir = workdir
+
+	var buffer bytes.Buffer
+	cmd.Stdout = io.MultiWriter(os.Stdout, &buffer)
+	cmd.Stderr = os.Stderr
+
+	err := cmd.Run()
+	return buffer.Bytes(), err
+}
+
+func createSigner(privateKey, mnemonic, hdPath string) (signer, error) {
+	path, err := accounts.ParseDerivationPath(hdPath)
+	if err != nil {
+		return nil, err
+	}
+
+	if privateKey != "" {
+		key, err := crypto.HexToECDSA(privateKey)
+		if err != nil {
+			return nil, fmt.Errorf("error parsing private key: %w", err)
+		}
+		return &ecdsaSigner{key}, nil
+	}
+
+	if mnemonic != "" {
+		key, err := derivePrivateKey(mnemonic, path)
+		if err != nil {
+			return nil, fmt.Errorf("error deriving key from mnemonic: %w", err)
+		}
+		return &ecdsaSigner{key}, nil
+	}
+
+	// assume using a ledger
+	ledgerHub, err := usbwallet.NewLedgerHub()
+	if err != nil {
+		return nil, fmt.Errorf("error starting ledger: %w", err)
+	}
+	wallets := ledgerHub.Wallets()
+	if len(wallets) == 0 {
+		return nil, fmt.Errorf("no ledgers found, please connect your ledger")
+	} else if len(wallets) > 1 {
+		return nil, fmt.Errorf("multiple ledgers found, please use one ledger at a time")
+	}
+	wallet := wallets[0]
+	if err := wallet.Open(""); err != nil {
+		return nil, fmt.Errorf("error opening ledger: %w", err)
+	}
+	account, err := wallet.Derive(path, true)
+	if err != nil {
+		return nil, fmt.Errorf("error deriving ledger account (have you unlocked?): %w", err)
+	}
+	return &walletSigner{
+		wallet:  wallet,
+		account: account,
+	}, nil
+}
+
+type signer interface {
+	address() common.Address
+	sign([]byte) ([]byte, error)
+}
+
+type ecdsaSigner struct {
+	*ecdsa.PrivateKey
+}
+
+func (s *ecdsaSigner) address() common.Address {
+	return crypto.PubkeyToAddress(s.PublicKey)
+}
+
+func (s *ecdsaSigner) sign(data []byte) ([]byte, error) {
+	sig, err := crypto.Sign(crypto.Keccak256(data), s.PrivateKey)
+	if err != nil {
+		return nil, err
+	}
+	sig[crypto.RecoveryIDOffset] += 27
+	return sig, err
+}
+
+type walletSigner struct {
+	wallet  accounts.Wallet
+	account accounts.Account
+}
+
+func (s *walletSigner) address() common.Address {
+	return s.account.Address
+}
+
+func (s *walletSigner) sign(data []byte) ([]byte, error) {
+	return s.wallet.SignData(s.account, accounts.MimetypeTypedData, data)
+}
+
+func derivePrivateKey(mnemonic string, path accounts.DerivationPath) (*ecdsa.PrivateKey, error) {
+	// Parse the seed string into the master BIP32 key.
+	seed, err := bip39.NewSeedWithErrorChecking(mnemonic, "")
+	if err != nil {
+		return nil, err
+	}
+
+	privKey, err := hdkeychain.NewMaster(seed, fakeNetworkParams{})
+	if err != nil {
+		return nil, err
+	}
+
+	for _, child := range path {
+		privKey, err = privKey.Child(child)
+		if err != nil {
+			return nil, err
+		}
+	}
+
+	rawPrivKey, err := privKey.SerializedPrivKey()
+	if err != nil {
+		return nil, err
+	}
+
+	return crypto.ToECDSA(rawPrivKey)
+}
+
+type fakeNetworkParams struct{}
+
+func (f fakeNetworkParams) HDPrivKeyVersion() [4]byte {
+	return [4]byte{}
+}
+
+func (f fakeNetworkParams) HDPubKeyVersion() [4]byte {
+	return [4]byte{}
+}