github.com/googgoog/go-ethereum@v1.9.7/accounts/abi/bind/auth.go (about)

     1  // Copyright 2016 The go-ethereum Authors
     2  // This file is part of the go-ethereum library.
     3  //
     4  // The go-ethereum library is free software: you can redistribute it and/or modify
     5  // it under the terms of the GNU Lesser General Public License as published by
     6  // the Free Software Foundation, either version 3 of the License, or
     7  // (at your option) any later version.
     8  //
     9  // The go-ethereum library is distributed in the hope that it will be useful,
    10  // but WITHOUT ANY WARRANTY; without even the implied warranty of
    11  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    12  // GNU Lesser General Public License for more details.
    13  //
    14  // You should have received a copy of the GNU Lesser General Public License
    15  // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
    16  
    17  package bind
    18  
    19  import (
    20  	"crypto/ecdsa"
    21  	"errors"
    22  	"io"
    23  	"io/ioutil"
    24  
    25  	"github.com/ethereum/go-ethereum/accounts"
    26  	"github.com/ethereum/go-ethereum/accounts/external"
    27  	"github.com/ethereum/go-ethereum/accounts/keystore"
    28  	"github.com/ethereum/go-ethereum/common"
    29  	"github.com/ethereum/go-ethereum/core/types"
    30  	"github.com/ethereum/go-ethereum/crypto"
    31  )
    32  
    33  // NewTransactor is a utility method to easily create a transaction signer from
    34  // an encrypted json key stream and the associated passphrase.
    35  func NewTransactor(keyin io.Reader, passphrase string) (*TransactOpts, error) {
    36  	json, err := ioutil.ReadAll(keyin)
    37  	if err != nil {
    38  		return nil, err
    39  	}
    40  	key, err := keystore.DecryptKey(json, passphrase)
    41  	if err != nil {
    42  		return nil, err
    43  	}
    44  	return NewKeyedTransactor(key.PrivateKey), nil
    45  }
    46  
    47  // NewKeyStoreTransactor is a utility method to easily create a transaction signer from
    48  // an decrypted key from a keystore
    49  func NewKeyStoreTransactor(keystore *keystore.KeyStore, account accounts.Account) (*TransactOpts, error) {
    50  	return &TransactOpts{
    51  		From: account.Address,
    52  		Signer: func(signer types.Signer, address common.Address, tx *types.Transaction) (*types.Transaction, error) {
    53  			if address != account.Address {
    54  				return nil, errors.New("not authorized to sign this account")
    55  			}
    56  			signature, err := keystore.SignHash(account, signer.Hash(tx).Bytes())
    57  			if err != nil {
    58  				return nil, err
    59  			}
    60  			return tx.WithSignature(signer, signature)
    61  		},
    62  	}, nil
    63  }
    64  
    65  // NewKeyedTransactor is a utility method to easily create a transaction signer
    66  // from a single private key.
    67  func NewKeyedTransactor(key *ecdsa.PrivateKey) *TransactOpts {
    68  	keyAddr := crypto.PubkeyToAddress(key.PublicKey)
    69  	return &TransactOpts{
    70  		From: keyAddr,
    71  		Signer: func(signer types.Signer, address common.Address, tx *types.Transaction) (*types.Transaction, error) {
    72  			if address != keyAddr {
    73  				return nil, errors.New("not authorized to sign this account")
    74  			}
    75  			signature, err := crypto.Sign(signer.Hash(tx).Bytes(), key)
    76  			if err != nil {
    77  				return nil, err
    78  			}
    79  			return tx.WithSignature(signer, signature)
    80  		},
    81  	}
    82  }
    83  
    84  // NewClefTransactor is a utility method to easily create a transaction signer
    85  // with a clef backend.
    86  func NewClefTransactor(clef *external.ExternalSigner, account accounts.Account) *TransactOpts {
    87  	return &TransactOpts{
    88  		From: account.Address,
    89  		Signer: func(signer types.Signer, address common.Address, transaction *types.Transaction) (*types.Transaction, error) {
    90  			if address != account.Address {
    91  				return nil, errors.New("not authorized to sign this account")
    92  			}
    93  			return clef.SignTx(account, transaction, nil) // Clef enforces its own chain id
    94  		},
    95  	}
    96  }