go-ethereum/accounts/scwallet/apdu.go
2019-04-08 13:21:22 +02:00

88 lines
2.6 KiB
Go

// Copyright 2018 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 scwallet
import (
"bytes"
"encoding/binary"
"fmt"
)
// commandAPDU represents an application data unit sent to a smartcard.
type commandAPDU struct {
Cla, Ins, P1, P2 uint8 // Class, Instruction, Parameter 1, Parameter 2
Data []byte // Command data
Le uint8 // Command data length
}
// serialize serializes a command APDU.
func (ca commandAPDU) serialize() ([]byte, error) {
buf := new(bytes.Buffer)
if err := binary.Write(buf, binary.BigEndian, ca.Cla); err != nil {
return nil, err
}
if err := binary.Write(buf, binary.BigEndian, ca.Ins); err != nil {
return nil, err
}
if err := binary.Write(buf, binary.BigEndian, ca.P1); err != nil {
return nil, err
}
if err := binary.Write(buf, binary.BigEndian, ca.P2); err != nil {
return nil, err
}
if len(ca.Data) > 0 {
if err := binary.Write(buf, binary.BigEndian, uint8(len(ca.Data))); err != nil {
return nil, err
}
if err := binary.Write(buf, binary.BigEndian, ca.Data); err != nil {
return nil, err
}
}
if err := binary.Write(buf, binary.BigEndian, ca.Le); err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// responseAPDU represents an application data unit received from a smart card.
type responseAPDU struct {
Data []byte // response data
Sw1, Sw2 uint8 // status words 1 and 2
}
// deserialize deserializes a response APDU.
func (ra *responseAPDU) deserialize(data []byte) error {
if len(data) < 2 {
return fmt.Errorf("can not deserialize data: payload too short (%d < 2)", len(data))
}
ra.Data = make([]byte, len(data)-2)
buf := bytes.NewReader(data)
if err := binary.Read(buf, binary.BigEndian, &ra.Data); err != nil {
return err
}
if err := binary.Read(buf, binary.BigEndian, &ra.Sw1); err != nil {
return err
}
if err := binary.Read(buf, binary.BigEndian, &ra.Sw2); err != nil {
return err
}
return nil
}