1 files changed, 96 insertions, 0 deletions
diff --git a/accounts/abi/bind/auth.go b/accounts/abi/bind/auth.go
new file mode 100644
index 0000000..c916cc4
--- /dev/null
+++ b/accounts/abi/bind/auth.go
@@ -0,0 +1,96 @@
+// Copyright 2016 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 bind
+
+import (
+	"crypto/ecdsa"
+	"errors"
+	"io"
+	"io/ioutil"
+
+	"github.com/ava-labs/coreth/accounts"
+	"github.com/ava-labs/coreth/accounts/external"
+	"github.com/ava-labs/coreth/accounts/keystore"
+	"github.com/ava-labs/coreth/core/types"
+	"github.com/ava-labs/go-ethereum/common"
+	"github.com/ava-labs/go-ethereum/crypto"
+)
+
+// NewTransactor is a utility method to easily create a transaction signer from
+// an encrypted json key stream and the associated passphrase.
+func NewTransactor(keyin io.Reader, passphrase string) (*TransactOpts, error) {
+	json, err := ioutil.ReadAll(keyin)
+	if err != nil {
+		return nil, err
+	}
+	key, err := keystore.DecryptKey(json, passphrase)
+	if err != nil {
+		return nil, err
+	}
+	return NewKeyedTransactor(key.PrivateKey), nil
+}
+
+// NewKeyStoreTransactor is a utility method to easily create a transaction signer from
+// an decrypted key from a keystore
+func NewKeyStoreTransactor(keystore *keystore.KeyStore, account accounts.Account) (*TransactOpts, error) {
+	return &TransactOpts{
+		From: account.Address,
+		Signer: func(signer types.Signer, address common.Address, tx *types.Transaction) (*types.Transaction, error) {
+			if address != account.Address {
+				return nil, errors.New("not authorized to sign this account")
+			}
+			signature, err := keystore.SignHash(account, signer.Hash(tx).Bytes())
+			if err != nil {
+				return nil, err
+			}
+			return tx.WithSignature(signer, signature)
+		},
+	}, nil
+}
+
+// NewKeyedTransactor is a utility method to easily create a transaction signer
+// from a single private key.
+func NewKeyedTransactor(key *ecdsa.PrivateKey) *TransactOpts {
+	keyAddr := crypto.PubkeyToAddress(key.PublicKey)
+	return &TransactOpts{
+		From: keyAddr,
+		Signer: func(signer types.Signer, address common.Address, tx *types.Transaction) (*types.Transaction, error) {
+			if address != keyAddr {
+				return nil, errors.New("not authorized to sign this account")
+			}
+			signature, err := crypto.Sign(signer.Hash(tx).Bytes(), key)
+			if err != nil {
+				return nil, err
+			}
+			return tx.WithSignature(signer, signature)
+		},
+	}
+}
+
+// NewClefTransactor is a utility method to easily create a transaction signer
+// with a clef backend.
+func NewClefTransactor(clef *external.ExternalSigner, account accounts.Account) *TransactOpts {
+	return &TransactOpts{
+		From: account.Address,
+		Signer: func(signer types.Signer, address common.Address, transaction *types.Transaction) (*types.Transaction, error) {
+			if address != account.Address {
+				return nil, errors.New("not authorized to sign this account")
+			}
+			return clef.SignTx(account, transaction, nil) // Clef enforces its own chain id
+		},
+	}
+}