ADD lnurl-auth support (@gocedoko)

Navigation.js

@@ -83,6 +83,7 @@ import LdkInfo from './screen/lnd/ldkInfo';
 import LNDViewAdditionalInvoiceInformation from './screen/lnd/lndViewAdditionalInvoiceInformation';
 import LnurlPay from './screen/lnd/lnurlPay';
 import LnurlPaySuccess from './screen/lnd/lnurlPaySuccess';
+import LnurlAuth from './screen/lnd/lnurlAuth';
 import UnlockWith from './UnlockWith';
 import DrawerList from './screen/wallets/drawerList';
 import { isDesktop, isTablet, isHandset } from './blue_modules/environment';
@@ -152,6 +153,7 @@ const WalletsRoot = () => {
       <WalletsStack.Screen name="IsItMyAddress" component={IsItMyAddress} options={IsItMyAddress.navigationOptions(theme)} />
       <WalletsStack.Screen name="LnurlPay" component={LnurlPay} options={LnurlPay.navigationOptions(theme)} />
       <WalletsStack.Screen name="LnurlPaySuccess" component={LnurlPaySuccess} options={LnurlPaySuccess.navigationOptions(theme)} />
+      <WalletsStack.Screen name="LnurlAuth" component={LnurlAuth} options={LnurlAuth.navigationOptions(theme)} />
       <WalletsStack.Screen
         name="Success"
         component={Success}

class/lnurl.js

@@ -1,6 +1,9 @@
 import { bech32 } from 'bech32';
 import bolt11 from 'bolt11';
 import { isTorDaemonDisabled } from '../blue_modules/environment';
+import { parse } from 'url'; // eslint-disable-line node/no-deprecated-api
+import { createHmac } from 'crypto';
+import secp256k1 from 'secp256k1';
 const CryptoJS = require('crypto-js');
 const createHash = require('create-hash');
 const torrific = require('../blue_modules/torrific');
@@ -12,6 +15,7 @@ const ONION_REGEX = /^(http:\/\/[^/:@]+\.onion(?::\d{1,5})?)(\/.*)?$/; // regex
 export default class Lnurl {
   static TAG_PAY_REQUEST = 'payRequest'; // type of LNURL
   static TAG_WITHDRAW_REQUEST = 'withdrawRequest'; // type of LNURL
+  static TAG_LOGIN_REQUEST = 'login'; // type of LNURL
 
   constructor(url, AsyncStorage) {
     this._lnurl = url;
@@ -285,6 +289,37 @@ export default class Lnurl {
     return this?._lnurlPayServicePayload?.commentAllowed ? parseInt(this._lnurlPayServicePayload.commentAllowed) : false;
   }
 
+  authenticate(secret) {
+    return new Promise((resolve, reject) => {
+      if (!this._lnurl) throw new Error('this._lnurl is not set');
+
+      const url = parse(Lnurl.getUrlFromLnurl(this._lnurl), true); // eslint-disable-line node/no-deprecated-api
+
+      const hmac = createHmac('sha256', secret);
+      hmac.on('readable', async () => {
+        try {
+          const privateKey = hmac.read();
+          if (!privateKey) return;
+          const privateKeyBuf = Buffer.from(privateKey, 'hex');
+          const publicKey = secp256k1.publicKeyCreate(privateKeyBuf);
+          const signatureObj = secp256k1.sign(Buffer.from(url.query.k1, 'hex'), privateKeyBuf);
+          const derSignature = secp256k1.signatureExport(signatureObj.signature);
+
+          const reply = await this.fetchGet(`${url.href}&sig=${derSignature.toString('hex')}&key=${publicKey.toString('hex')}`);
+          if (reply.status === 'OK') {
+            resolve();
+          } else {
+            reject(reply.reason);
+          }
+        } catch (err) {
+          reject(err);
+        }
+      });
+      hmac.write(url.hostname);
+      hmac.end();
+    });
+  }
+
   static isLightningAddress(address) {
     // ensure only 1 `@` present:
     if (address.split('@').length !== 2) return false;

class/wallets/lightning-custodian-wallet.js

@@ -667,6 +667,10 @@ export class LightningCustodianWallet extends LegacyWallet {
 
     return false;
   }
+
+  authenticate(lnurl) {
+    return lnurl.authenticate(this.secret);
+  }
 }
 
 /*

loc/de_de.json

@@ -658,5 +658,21 @@
     "type_receive": "Empfang",
     "type_used": "Verwendet",
     "transactions": "Transaktionen"
+  },
+  "lnurl_auth": {
+    "register_question_part_1": "Möchten Sie ein Konto bei",
+    "register_question_part_2": "mit Ihrem LN-Wallet registrieren?",
+    "register_answer": "Konto bei {hostname} erfolgreich registriert!",
+    "login_question_part_1": "Möchten Sie sich mit Ihrem LN-Wallet auf",
+    "login_question_part_2": "anmelden?",
+    "login_answer": "Erfolgreich angemeldet bei {hostname}!",
+    "link_question_part_1": "Möchten Sie Ihr Konto auf",
+    "link_question_part_2": "mit Ihrem LN-Wallet verknüpfen?",
+    "link_answer": "Ihr LN-Wallet wurde erfolgreich mit Ihrem Konto bei {hostname} verknüpft!",
+    "auth_question_part_1": "Möchten Sie sich mit Ihrem LN-Wallet bei",
+    "auth_question_part_2": "authentifizieren?",
+    "auth_answer": "Erfolgreich authentifiziert bei {hostname}!",
+    "could_not_auth": "Authentifizierung bei {hostname} fehlgeschlagen.",
+    "authenticate": "Authentifizieren"
   }
 }

loc/en.json

@@ -658,5 +658,21 @@
     "type_receive": "Receive",
     "type_used": "Used",
     "transactions": "Transactions"
+  },
+  "lnurl_auth": {
+    "register_question_part_1": "Do you want to register an account at ",
+    "register_question_part_2": "using your LN wallet?",
+    "register_answer": "Sucessfully registered an account at {hostname}!",
+    "login_question_part_1": "Do you want to login at ",
+    "login_question_part_2": "using your LN wallet?",
+    "login_answer": "Sucessfully logged in at {hostname}!",
+    "link_question_part_1": "Link your account at ",
+    "link_question_part_2": "to your LN wallet?",
+    "link_answer": "Your LN wallet was sucessfully linked to your account at {hostname}!",
+    "auth_question_part_1": "Do you want to authenticate at ",
+    "auth_question_part_2": "using your LN wallet?",
+    "auth_answer": "Sucessfully authenticated at {hostname}!",
+    "could_not_auth": "Could not authenticate to {hostname}.",
+    "authenticate": "Authenticate"
   }
 }

screen/lnd/lndCreateInvoice.js

@@ -28,6 +28,7 @@ import Lnurl from '../../class/lnurl';
 import { BlueStorageContext } from '../../blue_modules/storage-context';
 import Notifications from '../../blue_modules/notifications';
 import alert from '../../components/Alert';
+import { parse } from 'url'; // eslint-disable-line node/no-deprecated-api
 const currency = require('../../blue_modules/currency');
 const torrific = require('../../blue_modules/torrific');
 
@@ -223,6 +224,15 @@ const LNDCreateInvoice = () => {
 
     // decoding the lnurl
     const url = Lnurl.getUrlFromLnurl(data);
+    const { query } = parse(url, true); // eslint-disable-line node/no-deprecated-api
+
+    if (query.tag === Lnurl.TAG_LOGIN_REQUEST) {
+      navigate('LnurlAuth', {
+        lnurl: data,
+        walletID: walletID ?? wallet.current.getID(),
+      });
+      return;
+    }
 
     // calling the url
     let reply;

screen/lnd/lnurlAuth.js

@@ -0,0 +1,195 @@
+import React, { useState, useContext, useCallback, useMemo } from 'react';
+import { I18nManager, ScrollView, StyleSheet, Text, TouchableOpacity, View } from 'react-native';
+import { Icon } from 'react-native-elements';
+
+import { BlueButton, BlueCard, BlueLoading, BlueSpacing20, BlueSpacing40, BlueText, SafeBlueArea } from '../../BlueComponents';
+
+import navigationStyle from '../../components/navigationStyle';
+import Lnurl from '../../class/lnurl';
+import { Chain } from '../../models/bitcoinUnits';
+import loc from '../../loc';
+import { BlueStorageContext } from '../../blue_modules/storage-context';
+import { useNavigation, useRoute, useTheme } from '@react-navigation/native';
+import selectWallet from '../../helpers/select-wallet';
+import LottieView from 'lottie-react-native';
+import url from 'url';
+
+const AuthState = {
+  USER_PROMPT: 0,
+  IN_PROGRESS: 1,
+  SUCCESS: 2,
+  ERROR: 3,
+};
+
+const LnurlAuth = () => {
+  const { wallets } = useContext(BlueStorageContext);
+  const { name } = useRoute();
+  const { walletID, lnurl } = useRoute().params;
+  const wallet = useMemo(() => wallets.find(w => w.getID() === walletID), [wallets, walletID]);
+  const LN = useMemo(() => new Lnurl(lnurl), [lnurl]);
+  const parsedLnurl = useMemo(
+    () => (lnurl ? url.parse(Lnurl.getUrlFromLnurl(lnurl), true) : {}), // eslint-disable-line node/no-deprecated-api
+    [lnurl],
+  );
+  const [authState, setAuthState] = useState(AuthState.USER_PROMPT);
+  const [errMsg, setErrMsg] = useState('');
+  const { setParams, navigate } = useNavigation();
+  const { colors } = useTheme();
+  const stylesHook = StyleSheet.create({
+    root: {
+      backgroundColor: colors.background,
+    },
+    walletWrapLabel: {
+      color: colors.buttonAlternativeTextColor,
+    },
+  });
+
+  const showSelectWalletScreen = useCallback(() => {
+    selectWallet(navigate, name, Chain.OFFCHAIN).then(wallet => setParams({ walletID: wallet.getID() }));
+  }, [navigate, name, setParams]);
+
+  const authenticate = useCallback(() => {
+    wallet
+      .authenticate(LN)
+      .then(() => {
+        setAuthState(AuthState.SUCCESS);
+        setErrMsg('');
+      })
+      .catch(err => {
+        setAuthState(AuthState.ERROR);
+        setErrMsg(err);
+      });
+  }, [wallet, LN]);
+
+  if (!parsedLnurl || !wallet || authState === AuthState.IN_PROGRESS)
+    return (
+      <View style={[styles.root, stylesHook.root]}>
+        <BlueLoading />
+      </View>
+    );
+
+  const renderWalletSelectionButton = authState === AuthState.USER_PROMPT && (
+    <View style={styles.walletSelectRoot}>
+      {authState !== AuthState.IN_PROGRESS && (
+        <TouchableOpacity accessibilityRole="button" style={styles.walletSelectTouch} onPress={showSelectWalletScreen}>
+          <Text style={styles.walletSelectText}>{loc.wallets.select_wallet.toLowerCase()}</Text>
+          <Icon name={I18nManager.isRTL ? 'angle-left' : 'angle-right'} size={18} type="font-awesome" color="#9aa0aa" />
+        </TouchableOpacity>
+      )}
+      <View style={styles.walletWrap}>
+        <TouchableOpacity accessibilityRole="button" style={styles.walletWrapTouch} onPress={showSelectWalletScreen}>
+          <Text style={[styles.walletWrapLabel, stylesHook.walletWrapLabel]}>{wallet.getLabel()}</Text>
+        </TouchableOpacity>
+      </View>
+    </View>
+  );
+
+  return (
+    <SafeBlueArea style={styles.root}>
+      {authState === AuthState.USER_PROMPT && (
+        <>
+          <ScrollView>
+            <BlueCard>
+              <BlueText style={styles.alignSelfCenter}>{loc.lnurl_auth[`${parsedLnurl.query.action || 'auth'}_question_part_1`]}</BlueText>
+              <BlueText style={styles.domainName}>{parsedLnurl.hostname}</BlueText>
+              <BlueText style={styles.alignSelfCenter}>{loc.lnurl_auth[`${parsedLnurl.query.action || 'auth'}_question_part_2`]}</BlueText>
+              <BlueSpacing40 />
+              <BlueButton title={loc.lnurl_auth.authenticate} onPress={authenticate} />
+              <BlueSpacing40 />
+            </BlueCard>
+          </ScrollView>
+          {renderWalletSelectionButton}
+        </>
+      )}
+
+      {authState === AuthState.SUCCESS && (
+        <BlueCard>
+          <View style={styles.iconContainer}>
+            <LottieView style={styles.icon} source={require('../../img/bluenice.json')} autoPlay loop={false} />
+          </View>
+          <BlueSpacing20 />
+          <BlueText style={styles.alignSelfCenter}>
+            {loc.formatString(loc.lnurl_auth[`${parsedLnurl.query.action || 'auth'}_answer`], { hostname: parsedLnurl.hostname })}
+          </BlueText>
+          <BlueSpacing20 />
+        </BlueCard>
+      )}
+
+      {authState === AuthState.ERROR && (
+        <BlueCard>
+          <BlueSpacing20 />
+          <BlueText style={styles.alignSelfCenter}>
+            {loc.formatString(loc.lnurl_auth.could_not_auth, { hostname: parsedLnurl.hostname })}
+          </BlueText>
+          <BlueText style={styles.alignSelfCenter}>{errMsg}</BlueText>
+          <BlueSpacing20 />
+        </BlueCard>
+      )}
+    </SafeBlueArea>
+  );
+};
+
+export default LnurlAuth;
+
+const styles = StyleSheet.create({
+  alignSelfCenter: {
+    alignSelf: 'center',
+  },
+  domainName: {
+    alignSelf: 'center',
+    fontWeight: 'bold',
+    fontSize: 25,
+    paddingVertical: 10,
+  },
+  root: {
+    flex: 1,
+    justifyContent: 'center',
+  },
+  iconContainer: {
+    backgroundColor: '#ccddf9',
+    width: 120,
+    height: 120,
+    maxWidth: 120,
+    maxHeight: 120,
+    padding: 0,
+    borderRadius: 60,
+    alignSelf: 'center',
+    justifyContent: 'center',
+    alignItems: 'center',
+  },
+  icon: {
+    width: 400,
+    height: 400,
+  },
+  walletSelectRoot: {
+    alignItems: 'center',
+    justifyContent: 'flex-end',
+  },
+  walletSelectTouch: {
+    flexDirection: 'row',
+    alignItems: 'center',
+  },
+  walletSelectText: {
+    color: '#9aa0aa',
+    fontSize: 14,
+    marginRight: 8,
+  },
+  walletWrap: {
+    flexDirection: 'row',
+    alignItems: 'center',
+    marginVertical: 4,
+  },
+  walletWrapTouch: {
+    flexDirection: 'row',
+    alignItems: 'center',
+  },
+  walletWrapLabel: {
+    fontSize: 14,
+  },
+});
+
+LnurlAuth.navigationOptions = navigationStyle({
+  title: '',
+  closeButton: true,
+  closeButtonFunc: ({ navigation }) => navigation.dangerouslyGetParent().popToTop(),
+});

tests/unit/lnurl.test.js

@@ -226,6 +226,48 @@ describe('lightning address', function () {
     assert.ok(!Lnurl.isLightningAddress('a@'));
   });
 
+  it('can authenticate', async () => {
+    const LN = new Lnurl(
+      'LNURL1DP68GURN8GHJ7MRFVA58GMNFDENKCMM8D9HZUMRFWEJJ7MR0VA5KU0MTXY7NYVFEX93X2DFK8P3KVEFKVSEXZWR98PSNJVRRV5CRGCE3X4JKGE3HXPNXGCMPV5MXXVTZ89NXZENXXCURGCTRV93RVE35XQCXVCFSVSN8GCT884KX7EMFDCDKKXQ0',
+    );
+
+    // poor-man's mock:
+    LN._fetchGet = LN.fetchGet;
+    let requestedUri = -1;
+    LN.fetchGet = actuallyRequestedUri => {
+      requestedUri = actuallyRequestedUri;
+      return {
+        status: 'OK',
+      };
+    };
+
+    await assert.doesNotReject(LN.authenticate('lndhub://dc56b8cf8ef3b60060cf:94eac57510de2738451d'));
+    assert.strictEqual(
+      requestedUri,
+      'https://lightninglogin.live/login?k1=2191be568cfe6d2a8e8a90ce04c15edf70fdcae6c1b9faff684acab6f400fa0d&tag=login&sig=304502210093ab4ead8dd619f2ddb3d52bd4bb01725badcb2a3daa3870fb41a38096f9a37d0220464a32e94e13dcec20ea94b94df0fa52f45cd88b01d7247042136ad0c71752d2&key=03e7b61e57efff1925ab9082625400cae2c8ad88a984e7aa4987abb77818570018',
+    );
+  });
+
+  it('returns the server error response as the reject error from lnurl-auth', async () => {
+    const LN = new Lnurl(
+      'LNURL1DP68GURN8GHJ7MRFVA58GMNFDENKCMM8D9HZUMRFWEJJ7MR0VA5KU0MTXY7NYVFEX93X2DFK8P3KVEFKVSEXZWR98PSNJVRRV5CRGCE3X4JKGE3HXPNXGCMPV5MXXVTZ89NXZENXXCURGCTRV93RVE35XQCXVCFSVSN8GCT884KX7EMFDCDKKXQ0',
+    );
+
+    // poor-man's mock:
+    LN._fetchGet = LN.fetchGet;
+    LN.fetchGet = () => {
+      return {
+        reason: 'Invalid signature',
+        status: 'ERROR',
+      };
+    };
+
+    await assert.rejects(LN.authenticate('lndhub://dc56b8cf8ef3b60060cf:94eac57510de2738451d'), err => {
+      assert.strictEqual(err, 'Invalid signature');
+      return true;
+    });
+  });
+
   it('works', async () => {
     const LN = new Lnurl('lnaddress@zbd.gg');