feat: adds support for BIP39 mnemonics (#577)

* feat: bip39 support for evm keys * chore: go mod tidy * Update cmd/blobstream/keys/evm/evm.go * Update cmd/blobstream/keys/evm/evm.go * chore: better password message * feat: support bip39 passphrases * Update cmd/blobstream/keys/evm/evm.go Co-authored-by: Evan Forbes <[email protected]> --------- Co-authored-by: Evan Forbes <[email protected]>
celestiaorg · Nov 7, 2023 · 4f66954 · 4f66954
1 parent 87d842a
commit 4f66954
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Showing 3 changed files with 246 additions and 3 deletions.
diff --git a/cmd/blobstream/keys/evm/evm.go b/cmd/blobstream/keys/evm/evm.go
@@ -1,11 +1,18 @@
 package evm
 
 import (
+	"bufio"
 	"bytes"
+	"crypto/ecdsa"
+	"errors"
 	"fmt"
 	"io"
 	"os"
 
+	"github.com/cosmos/cosmos-sdk/client/input"
+	"github.com/cosmos/cosmos-sdk/crypto/hd"
+	"github.com/cosmos/go-bip39"
+
 	"github.com/ethereum/go-ethereum/accounts/keystore"
 
 	common2 "github.com/celestiaorg/orchestrator-relayer/cmd/blobstream/keys/common"
@@ -18,6 +25,8 @@ import (
 	"golang.org/x/term"
 )
 
+const mnemonicEntropySize = 256
+
 func Root(serviceName string) *cobra.Command {
 	evmCmd := &cobra.Command{
 		Use:          "evm",
@@ -74,6 +83,15 @@ func Add(serviceName string) *cobra.Command {
 				}
 			}(s, logger)
 
+			bip39Passphrase, err := GetBIP39Passphrase()
+			if err != nil {
+				return err
+			}
+
+			if bip39Passphrase != "" {
+				fmt.Println("\nThe provided passphrase will be the 25th word in your mnemonic. Make sure to save it as you won't be able to recover your accounts without it.")
+			}
+
 			passphrase := config.EVMPassphrase
 			// if the passphrase is not specified as a flag, ask for it.
 			if passphrase == "" {
@@ -83,11 +101,39 @@ func Add(serviceName string) *cobra.Command {
 				}
 			}
 
-			account, err := s.EVMKeyStore.NewAccount(passphrase)
+			// read entropy seed straight from tmcrypto.Rand and convert to mnemonic
+			entropySeed, err := bip39.NewEntropy(mnemonicEntropySize)
+			if err != nil {
+				return err
+			}
+
+			mnemonic, err := bip39.NewMnemonic(entropySeed)
+			if err != nil {
+				return err
+			}
+
+			// get the private key using an empty passphrase so that only the mnemonic
+			// is enough to recover the account
+			ethPrivKey, err := MnemonicToPrivateKey(mnemonic, bip39Passphrase)
 			if err != nil {
 				return err
 			}
+
+			account, err := s.EVMKeyStore.ImportECDSA(ethPrivKey, passphrase)
+			if err != nil {
+				return err
+			}
+
 			logger.Info("account created successfully", "address", account.Address.String())
+
+			fmt.Println("\n\n**Important** write this mnemonic phrase in a safe place." +
+				"\nIt is the only way to recover your account if you ever forget your storage password.")
+
+			if bip39Passphrase == "" {
+				fmt.Printf("\n%s\n\n", mnemonic)
+			} else {
+				fmt.Printf("\n%s <your_bip39_passphrase>\n\n", mnemonic)
+			}
 			return nil
 		},
 	}
@@ -221,6 +267,7 @@ func Import(serviceName string) *cobra.Command {
 	importCmd.AddCommand(
 		ImportFile(serviceName),
 		ImportECDSA(serviceName),
+		ImportMnemonic(serviceName),
 	)
 
 	importCmd.SetHelpCommand(&cobra.Command{})
@@ -379,6 +426,87 @@ func ImportECDSA(serviceName string) *cobra.Command {
 	return keysConfigFlags(&cmd, serviceName)
 }
 
+func ImportMnemonic(serviceName string) *cobra.Command {
+	cmd := cobra.Command{
+		Use:   "mnemonic",
+		Args:  cobra.ExactArgs(0),
+		Short: "import an EVM private key from a 24 words BIP39 mnemonic phrase",
+		RunE: func(cmd *cobra.Command, args []string) error {
+			config, err := parseKeysConfigFlags(cmd, serviceName)
+			if err != nil {
+				return err
+			}
+
+			logger := tmlog.NewTMLogger(os.Stdout)
+
+			initOptions := store.InitOptions{NeedEVMKeyStore: true}
+			isInit := store.IsInit(logger, config.Home, initOptions)
+
+			// initialize the store if not initialized
+			if !isInit {
+				err := store.Init(logger, config.Home, initOptions)
+				if err != nil {
+					return err
+				}
+			}
+
+			// open store
+			openOptions := store.OpenOptions{HasEVMKeyStore: true}
+			s, err := store.OpenStore(logger, config.Home, openOptions)
+			if err != nil {
+				return err
+			}
+			defer func(s *store.Store, log tmlog.Logger) {
+				err := s.Close(log, openOptions)
+				if err != nil {
+					logger.Error(err.Error())
+				}
+			}(s, logger)
+
+			// get the mnemonic from user input
+			inBuf := bufio.NewReader(os.Stdin)
+			mnemonic, err := input.GetString("Enter your bip39 mnemonic", inBuf)
+			if err != nil {
+				return err
+			}
+			if !bip39.IsMnemonicValid(mnemonic) {
+				return errors.New("invalid mnemonic")
+			}
+
+			bip39Passphrase, err := GetBIP39Passphrase()
+			if err != nil {
+				return err
+			}
+
+			// get the passphrase to use for the seed
+			passphrase := config.EVMPassphrase
+			// if the passphrase is not specified as a flag, ask for it.
+			if passphrase == "" {
+				passphrase, err = GetNewPassphrase()
+				if err != nil {
+					return err
+				}
+			}
+
+			logger.Info("importing account")
+
+			ethPrivKey, err := MnemonicToPrivateKey(mnemonic, bip39Passphrase)
+			if err != nil {
+				return err
+			}
+
+			account, err := s.EVMKeyStore.ImportECDSA(ethPrivKey, passphrase)
+			if err != nil {
+				return err
+			}
+
+			logger.Info("successfully imported key", "address", account.Address.String())
+			return nil
+		},
+	}
+	return keysConfigFlags(&cmd, serviceName)
+}
+
 func Update(serviceName string) *cobra.Command {
 	cmd := cobra.Command{
 		Use:   "update <account address in hex>",
@@ -509,20 +637,73 @@ func GetNewPassphrase() (string, error) {
 	var err error
 	var bzPassphrase []byte
 	for {
-		fmt.Print("please provide the account new passphrase: ")
+		fmt.Print("\nplease provide the account new passphrase (Note: this is for the store encryption and not the BIP39 passphrase. This means that you can recover your account without providing it): ")
+		bzPassphrase, err = term.ReadPassword(int(os.Stdin.Fd()))
+		if err != nil {
+			return "", err
+		}
+		fmt.Print("\nenter the same passphrase again: ")
+		bzPassphraseConfirm, err := term.ReadPassword(int(os.Stdin.Fd()))
+		if err != nil {
+			return "", err
+		}
+		if bytes.Equal(bzPassphrase, bzPassphraseConfirm) {
+			fmt.Println()
+			break
+		}
+		fmt.Print("\npassphrase and confirmation mismatch.\n")
+	}
+	return string(bzPassphrase), nil
+}
+
+func GetBIP39Passphrase() (string, error) {
+	var err error
+	var bzPassphrase []byte
+	for {
+		fmt.Print("\nplease provide the BIP39 passphrase (leave empty if you don't want to set a BIP39 passphrase, i.e. 25th mnemonic word): ")
 		bzPassphrase, err = term.ReadPassword(int(os.Stdin.Fd()))
 		if err != nil {
 			return "", err
 		}
+		if len(string(bzPassphrase)) > 100 {
+			fmt.Println("\n\nThe BIP39 passphrase cannot have more than 100 characters! Please try again.")
+			continue
+		}
 		fmt.Print("\nenter the same passphrase again: ")
 		bzPassphraseConfirm, err := term.ReadPassword(int(os.Stdin.Fd()))
 		if err != nil {
 			return "", err
 		}
 		if bytes.Equal(bzPassphrase, bzPassphraseConfirm) {
+			fmt.Println()
 			break
 		}
 		fmt.Print("\npassphrase and confirmation mismatch.\n")
 	}
 	return string(bzPassphrase), nil
 }
+
+// MnemonicToPrivateKey derives a private key from the provided mnemonic.
+// It uses the default derivation path, geth.DefaultBaseDerivationPath, i.e. m/44'/60'/0'/0, to generate
+// the first private key. The generated account is of path m/44'/60'/0'/0/0.
+func MnemonicToPrivateKey(mnemonic string, passphrase string) (*ecdsa.PrivateKey, error) {
+	// create the master key
+	seed, err := bip39.NewSeedWithErrorChecking(mnemonic, passphrase)
+	if err != nil {
+		return nil, err
+	}
+
+	secret, chainCode := hd.ComputeMastersFromSeed(seed)
+
+	// derive the first private key from the master key
+	key, err := hd.DerivePrivateKeyForPath(secret, chainCode, accounts.DefaultBaseDerivationPath.String())
+	if err != nil {
+		return nil, err
+	}
+
+	ethPrivKey, err := ethcrypto.ToECDSA(key)
+	if err != nil {
+		return nil, err
+	}
+	return ethPrivKey, nil
+}
diff --git a/cmd/blobstream/keys/evm/evm_test.go b/cmd/blobstream/keys/evm/evm_test.go
@@ -0,0 +1,62 @@
+package evm_test
+
+import (
+	"testing"
+
+	"github.com/celestiaorg/orchestrator-relayer/cmd/blobstream/keys/evm"
+	"github.com/ethereum/go-ethereum/crypto"
+	"github.com/stretchr/testify/assert"
+)
+
+// TestMnemonicToPrivateKey tests the generation of private keys using mnemonics.
+// The test vectors were generated and verified using a Ledger Nano X with Ethereum accounts.
+func TestMnemonicToPrivateKey(t *testing.T) {
+	tests := []struct {
+		name            string
+		mnemonic        string
+		passphrase      string
+		expectedError   bool
+		expectedResult  string
+		expectedAddress string
+	}{
+		{
+			name:            "Valid Mnemonic with passphrase",
+			mnemonic:        "eight moment square film same crystal trophy diagram awkward defense crazy garlic exile rabbit coast truck foam broken shed attract bamboo drum dry cage",
+			passphrase:      "abcd",
+			expectedError:   false,
+			expectedResult:  "5dfb97434a8a31cca1d1c2c6b6b9cf09b4946823331ec434894f204acf79d850",
+			expectedAddress: "0x6Ca3653B3B50892e051Da60b1E14540f2f7EBdBF",
+		},
+		{
+			name:            "Valid Mnemonic without passphrase",
+			mnemonic:        "eight moment square film same crystal trophy diagram awkward defense crazy garlic exile rabbit coast truck foam broken shed attract bamboo drum dry cage",
+			passphrase:      "",
+			expectedError:   false,
+			expectedResult:  "4252916c6e7f80dc96928c66a885be5a362790ad2fb3552ab781cd9112aef3a2",
+			expectedAddress: "0x33bb23EB923C284fC76D93C26aFd1FdCAf770Ea2",
+		},
+		{
+			name:          "Invalid Mnemonic",
+			mnemonic:      "wrong mnemonic beginning poverty injury cradle wrong smoke sphere trap tumble girl monkey sibling festival mask second agent slice gadget census glare swear recycle",
+			expectedError: true,
+		},
+	}
+
+	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
+			privateKey, err := evm.MnemonicToPrivateKey(test.mnemonic, test.passphrase)
+
+			if test.expectedError {
+				assert.Error(t, err)
+			} else {
+				assert.NoError(t, err)
+				addr := crypto.PubkeyToAddress(privateKey.PublicKey)
+				assert.Equal(t, test.expectedAddress, addr.Hex())
+
+				expectedPrivateKey, err := crypto.HexToECDSA(test.expectedResult)
+				assert.NoError(t, err)
+				assert.Equal(t, expectedPrivateKey.D.Bytes(), privateKey.D.Bytes())
+			}
+		})
+	}
+}
diff --git a/go.mod b/go.mod
@@ -26,6 +26,7 @@ require (
 require (
 	github.com/celestiaorg/blobstream-contracts/v3 v3.1.0
 	github.com/cosmos/cosmos-sdk v0.46.14
+	github.com/cosmos/go-bip39 v1.0.0
 	github.com/dgraph-io/badger/v2 v2.2007.4
 	github.com/ipfs/boxo v0.15.0
 	github.com/ipfs/go-datastore v0.6.0
@@ -84,7 +85,6 @@ require (
 	github.com/coreos/go-systemd/v22 v22.5.0 // indirect
 	github.com/cosmos/btcutil v1.0.5 // indirect
 	github.com/cosmos/cosmos-proto v1.0.0-alpha8 // indirect
-	github.com/cosmos/go-bip39 v1.0.0 // indirect
 	github.com/cosmos/gogoproto v1.4.11 // indirect
 	github.com/cosmos/gorocksdb v1.2.0 // indirect
 	github.com/cosmos/iavl v0.19.6 // indirect