github.com/mysteriumnetwork/node@v0.0.0-20240516044423-365054f76801/identity/signer.go (about)

     1  /*
     2   * Copyright (C) 2017 The "MysteriumNetwork/node" Authors.
     3   *
     4   * This program is free software: you can redistribute it and/or modify
     5   * it under the terms of the GNU 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   * This program 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 General Public License for more details.
    13   *
    14   * You should have received a copy of the GNU General Public License
    15   * along with this program.  If not, see <http://www.gnu.org/licenses/>.
    16   */
    17  
    18  package identity
    19  
    20  import (
    21  	"github.com/ethereum/go-ethereum/accounts"
    22  	"github.com/ethereum/go-ethereum/crypto"
    23  )
    24  
    25  // SignerFactory callback returning Signer
    26  type SignerFactory func(id Identity) Signer
    27  
    28  // Signer interface signifies an ability to sign a message
    29  type Signer interface {
    30  	Sign(message []byte) (Signature, error)
    31  }
    32  
    33  type keystoreSigner struct {
    34  	keystore keystore
    35  	account  accounts.Account
    36  }
    37  
    38  // NewSigner returns new instance of Signer
    39  func NewSigner(keystore keystore, identity Identity) Signer {
    40  	account := identityToAccount(identity)
    41  
    42  	return &keystoreSigner{
    43  		keystore: keystore,
    44  		account:  account,
    45  	}
    46  }
    47  
    48  // Sign signs given message and returns signature
    49  func (ksSigner *keystoreSigner) Sign(message []byte) (Signature, error) {
    50  	signature, err := ksSigner.keystore.SignHash(ksSigner.account, messageHash(message))
    51  	if err != nil {
    52  		return Signature{}, err
    53  	}
    54  
    55  	return SignatureBytes(signature), nil
    56  }
    57  
    58  func messageHash(data []byte) []byte {
    59  	return crypto.Keccak256(data)
    60  }