electrum/electrum/plugins/ledger/auth2fa.py

import copy

from PyQt5.QtWidgets import (QDialog, QLineEdit, QTextEdit, QVBoxLayout, QLabel,
                             QWidget, QHBoxLayout, QComboBox)

from btchip.btchip import BTChipException

from electrum.i18n import _
from electrum import constants, bitcoin
from electrum.logging import get_logger


_logger = get_logger(__name__)


DEBUG = False

helpTxt = [_("Your Ledger Wallet wants to tell you a one-time PIN code.<br><br>" \
            "For best security you should unplug your device, open a text editor on another computer, " \
            "put your cursor into it, and plug your device into that computer. " \
            "It will output a summary of the transaction being signed and a one-time PIN.<br><br>" \
            "Verify the transaction summary and type the PIN code here.<br><br>" \
            "Before pressing enter, plug the device back into this computer.<br>" ),
        _("Verify the address below.<br>Type the character from your security card corresponding to the <u><b>BOLD</b></u> character."),
        ]

class LedgerAuthDialog(QDialog):
    def __init__(self, handler, data):
        '''Ask user for 2nd factor authentication. Support text and security card methods.
        Use last method from settings, but support downgrade.
        '''
        QDialog.__init__(self, handler.top_level_window())
        self.handler = handler
        self.txdata = data
        self.idxs = self.txdata['keycardData'] if self.txdata['confirmationType'] > 1 else ''
        self.setMinimumWidth(650)
        self.setWindowTitle(_("Ledger Wallet Authentication"))
        self.cfg = copy.deepcopy(self.handler.win.wallet.get_keystore().cfg)
        self.dongle = self.handler.win.wallet.get_keystore().get_client().dongle
        self.pin = ''
        
        self.devmode = self.getDevice2FAMode()
        if self.devmode == 0x11 or self.txdata['confirmationType'] == 1:
            self.cfg['mode'] = 0
        
        vbox = QVBoxLayout()
        self.setLayout(vbox)
        
        def on_change_mode(idx):
            self.cfg['mode'] = 0 if self.devmode == 0x11 else idx if idx > 0 else 1
            if self.cfg['mode'] > 0:
                self.handler.win.wallet.get_keystore().cfg = self.cfg
                self.handler.win.wallet.save_keystore()
            self.update_dlg()
        def return_pin():
            self.pin = self.pintxt.text() if self.txdata['confirmationType'] == 1 else self.cardtxt.text() 
            if self.cfg['mode'] == 1:
                self.pin = ''.join(chr(int(str(i),16)) for i in self.pin)
            self.accept()
        
        self.modebox = QWidget()
        modelayout = QHBoxLayout()
        self.modebox.setLayout(modelayout)
        modelayout.addWidget(QLabel(_("Method:")))
        self.modes = QComboBox()
        modelayout.addWidget(self.modes, 2)
        modelayout.addStretch(1)
        self.modebox.setMaximumHeight(50)
        vbox.addWidget(self.modebox)
        
        self.populate_modes()
        self.modes.currentIndexChanged.connect(on_change_mode)

        self.helpmsg = QTextEdit()
        self.helpmsg.setStyleSheet("QTextEdit { background-color: lightgray; }")
        self.helpmsg.setReadOnly(True)
        vbox.addWidget(self.helpmsg)
        
        self.pinbox = QWidget()
        pinlayout = QHBoxLayout()
        self.pinbox.setLayout(pinlayout)
        self.pintxt = QLineEdit()
        self.pintxt.setEchoMode(2)
        self.pintxt.setMaxLength(4)
        self.pintxt.returnPressed.connect(return_pin)
        pinlayout.addWidget(QLabel(_("Enter PIN:")))
        pinlayout.addWidget(self.pintxt)
        pinlayout.addWidget(QLabel(_("NOT DEVICE PIN - see above")))
        pinlayout.addStretch(1)
        self.pinbox.setVisible(self.cfg['mode'] == 0)
        vbox.addWidget(self.pinbox)
                    
        self.cardbox = QWidget()
        card = QVBoxLayout()
        self.cardbox.setLayout(card)
        self.addrtext = QTextEdit()
        self.addrtext.setStyleSheet("QTextEdit { color:blue; background-color:lightgray; padding:15px 10px; border:none; font-size:20pt; font-family:monospace; }")
        self.addrtext.setReadOnly(True)
        self.addrtext.setMaximumHeight(130)
        card.addWidget(self.addrtext)
        
        def pin_changed(s):
            if len(s) < len(self.idxs):
                i = self.idxs[len(s)]
                addr = self.txdata['address']
                if not constants.net.TESTNET:
                    text = addr[:i] + '<u><b>' + addr[i:i+1] + '</u></b>' + addr[i+1:]
                else:
                    # pin needs to be created from mainnet address
                    addr_mainnet = bitcoin.script_to_address(bitcoin.address_to_script(addr), net=constants.BitcoinMainnet)
                    addr_mainnet = addr_mainnet[:i] + '<u><b>' + addr_mainnet[i:i+1] + '</u></b>' + addr_mainnet[i+1:]
                    text = str(addr) + '\n' + str(addr_mainnet)
                self.addrtext.setHtml(str(text))
            else:
                self.addrtext.setHtml(_("Press Enter"))
                
        pin_changed('')    
        cardpin = QHBoxLayout()
        cardpin.addWidget(QLabel(_("Enter PIN:")))
        self.cardtxt = QLineEdit()
        self.cardtxt.setEchoMode(2)
        self.cardtxt.setMaxLength(len(self.idxs))
        self.cardtxt.textChanged.connect(pin_changed)
        self.cardtxt.returnPressed.connect(return_pin)
        cardpin.addWidget(self.cardtxt)
        cardpin.addWidget(QLabel(_("NOT DEVICE PIN - see above")))
        cardpin.addStretch(1)
        card.addLayout(cardpin)
        self.cardbox.setVisible(self.cfg['mode'] == 1)
        vbox.addWidget(self.cardbox)
        
        self.update_dlg()

    def populate_modes(self):
        self.modes.blockSignals(True)
        self.modes.clear()
        self.modes.addItem(_("Summary Text PIN (requires dongle replugging)") if self.txdata['confirmationType'] == 1 else _("Summary Text PIN is Disabled"))
        if self.txdata['confirmationType'] > 1:
            self.modes.addItem(_("Security Card Challenge"))
        self.modes.blockSignals(False)
        
    def update_dlg(self):
        self.modes.setCurrentIndex(self.cfg['mode'])
        self.modebox.setVisible(True)
        self.helpmsg.setText(helpTxt[self.cfg['mode']])
        self.helpmsg.setMinimumHeight(180 if self.txdata['confirmationType'] == 1 else 100)
        self.helpmsg.setVisible(True)
        self.pinbox.setVisible(self.cfg['mode'] == 0)
        self.cardbox.setVisible(self.cfg['mode'] == 1)
        self.pintxt.setFocus(True) if self.cfg['mode'] == 0 else self.cardtxt.setFocus(True)
        self.setMaximumHeight(400)

    def getDevice2FAMode(self):
        apdu = [0xe0, 0x24, 0x01, 0x00, 0x00, 0x01] # get 2fa mode
        try:
            mode = self.dongle.exchange( bytearray(apdu) )
            return mode
        except BTChipException as e:
            _logger.debug('Device getMode Failed')
        return 0x11