BlueWallet/class/lnurl.js

320 lines
9.8 KiB
JavaScript

import { bech32 } from 'bech32';
import bolt11 from 'bolt11';
import { isTorDaemonDisabled } from '../blue_modules/environment';
const CryptoJS = require('crypto-js');
const createHash = require('create-hash');
const torrific = require('../blue_modules/torrific');
const ONION_REGEX = /^(http:\/\/[^/:@]+\.onion(?::\d{1,5})?)(\/.*)?$/; // regex for onion URL
/**
* @see https://github.com/btcontract/lnurl-rfc/blob/master/lnurl-pay.md
*/
export default class Lnurl {
static TAG_PAY_REQUEST = 'payRequest'; // type of LNURL
static TAG_WITHDRAW_REQUEST = 'withdrawRequest'; // type of LNURL
constructor(url, AsyncStorage) {
this._lnurl = url;
this._lnurlPayServiceBolt11Payload = false;
this._lnurlPayServicePayload = false;
this._AsyncStorage = AsyncStorage;
this._preimage = false;
}
static findlnurl(bodyOfText) {
const res = /^(?:http.*[&?]lightning=|lightning:)?(lnurl1[02-9ac-hj-np-z]+)/.exec(bodyOfText.toLowerCase());
if (res) {
return res[1];
}
return null;
}
static getUrlFromLnurl(lnurlExample) {
const found = Lnurl.findlnurl(lnurlExample);
if (!found) {
if (Lnurl.isLightningAddress(lnurlExample)) {
const username = lnurlExample.split('@')[0].trim();
const host = lnurlExample.split('@')[1].trim();
const proto = host.match(/\.onion$/) ? 'http' : 'https';
return `${proto}://${host}/.well-known/lnurlp/${username}`;
} else {
return false;
}
}
const decoded = bech32.decode(found, 10000);
return Buffer.from(bech32.fromWords(decoded.words)).toString();
}
static isLnurl(url) {
return Lnurl.findlnurl(url) !== null;
}
static isOnionUrl(url) {
return Lnurl.parseOnionUrl(url) !== null;
}
static parseOnionUrl(url) {
const match = url.match(ONION_REGEX);
if (match === null) return null;
const [, baseURI, path] = match;
return [baseURI, path];
}
async fetchGet(url) {
const parsedOnionUrl = Lnurl.parseOnionUrl(url);
if (parsedOnionUrl) {
return _fetchGetTor(parsedOnionUrl);
}
const resp = await fetch(url, { method: 'GET' });
if (resp.status >= 300) {
throw new Error('Bad response from server');
}
const reply = await resp.json();
if (reply.status === 'ERROR') {
throw new Error('Reply from server: ' + reply.reason);
}
return reply;
}
decodeInvoice(invoice) {
const { payeeNodeKey, tags, satoshis, millisatoshis, timestamp } = bolt11.decode(invoice);
const decoded = {
destination: payeeNodeKey,
num_satoshis: satoshis ? satoshis.toString() : '0',
num_millisatoshis: millisatoshis ? millisatoshis.toString() : '0',
timestamp: timestamp.toString(),
fallback_addr: '',
route_hints: [],
};
for (let i = 0; i < tags.length; i++) {
const { tagName, data } = tags[i];
switch (tagName) {
case 'payment_hash':
decoded.payment_hash = data;
break;
case 'purpose_commit_hash':
decoded.description_hash = data;
break;
case 'min_final_cltv_expiry':
decoded.cltv_expiry = data.toString();
break;
case 'expire_time':
decoded.expiry = data.toString();
break;
case 'description':
decoded.description = data;
break;
}
}
if (!decoded.expiry) decoded.expiry = '3600'; // default
if (parseInt(decoded.num_satoshis) === 0 && decoded.num_millisatoshis > 0) {
decoded.num_satoshis = (decoded.num_millisatoshis / 1000).toString();
}
return decoded;
}
async requestBolt11FromLnurlPayService(amountSat, comment = '') {
if (!this._lnurlPayServicePayload) throw new Error('this._lnurlPayServicePayload is not set');
if (!this._lnurlPayServicePayload.callback) throw new Error('this._lnurlPayServicePayload.callback is not set');
if (amountSat < this._lnurlPayServicePayload.min || amountSat > this._lnurlPayServicePayload.max)
throw new Error(
'The specified amount is invalid, ' +
amountSat +
' it should be between ' +
this._lnurlPayServicePayload.min +
' and ' +
this._lnurlPayServicePayload.max,
);
const nonce = Math.floor(Math.random() * 2e16).toString(16);
const separator = this._lnurlPayServicePayload.callback.indexOf('?') === -1 ? '?' : '&';
if (this.getCommentAllowed() && comment && comment.length > this.getCommentAllowed()) {
comment = comment.substr(0, this.getCommentAllowed());
}
if (comment) comment = `&comment=${encodeURIComponent(comment)}`;
const urlToFetch =
this._lnurlPayServicePayload.callback + separator + 'amount=' + Math.floor(amountSat * 1000) + '&nonce=' + nonce + comment;
this._lnurlPayServiceBolt11Payload = await this.fetchGet(urlToFetch);
if (this._lnurlPayServiceBolt11Payload.status === 'ERROR')
throw new Error(this._lnurlPayServiceBolt11Payload.reason || 'requestBolt11FromLnurlPayService() error');
// check pr description_hash, amount etc:
const decoded = this.decodeInvoice(this._lnurlPayServiceBolt11Payload.pr);
const metadataHash = createHash('sha256').update(this._lnurlPayServicePayload.metadata).digest('hex');
if (metadataHash !== decoded.description_hash) {
throw new Error(`Invoice description_hash doesn't match metadata.`);
}
if (parseInt(decoded.num_satoshis) !== Math.round(amountSat)) {
throw new Error(`Invoice doesn't match specified amount, got ${decoded.num_satoshis}, expected ${Math.round(amountSat)}`);
}
return this._lnurlPayServiceBolt11Payload;
}
async callLnurlPayService() {
if (!this._lnurl) throw new Error('this._lnurl is not set');
const url = Lnurl.getUrlFromLnurl(this._lnurl);
// calling the url
const reply = await this.fetchGet(url);
if (reply.tag !== Lnurl.TAG_PAY_REQUEST) {
throw new Error('lnurl-pay expected, found tag ' + reply.tag);
}
const data = reply;
// parse metadata and extract things from it
let image;
let description;
const kvs = JSON.parse(data.metadata);
for (let i = 0; i < kvs.length; i++) {
const [k, v] = kvs[i];
switch (k) {
case 'text/plain':
description = v;
break;
case 'image/png;base64':
case 'image/jpeg;base64':
image = 'data:' + k + ',' + v;
break;
}
}
// setting the payment screen with the parameters
const min = Math.ceil((data.minSendable || 0) / 1000);
const max = Math.floor(data.maxSendable / 1000);
this._lnurlPayServicePayload = {
callback: data.callback,
fixed: min === max,
min,
max,
domain: data.callback.match(/^(https|http):\/\/([^/]+)\//)[2],
metadata: data.metadata,
description,
image,
amount: min,
commentAllowed: data.commentAllowed,
// lnurl: uri,
};
return this._lnurlPayServicePayload;
}
async loadSuccessfulPayment(paymentHash) {
if (!paymentHash) throw new Error('No paymentHash provided');
let data;
try {
data = await this._AsyncStorage.getItem('lnurlpay_success_data_' + paymentHash);
data = JSON.parse(data);
} catch (_) {
return false;
}
if (!data) return false;
this._lnurlPayServicePayload = data.lnurlPayServicePayload;
this._lnurlPayServiceBolt11Payload = data.lnurlPayServiceBolt11Payload;
this._lnurl = data.lnurl;
this._preimage = data.preimage;
return true;
}
async storeSuccess(paymentHash, preimage) {
if (typeof preimage === 'object') {
preimage = Buffer.from(preimage.data).toString('hex');
}
this._preimage = preimage;
await this._AsyncStorage.setItem(
'lnurlpay_success_data_' + paymentHash,
JSON.stringify({
lnurlPayServicePayload: this._lnurlPayServicePayload,
lnurlPayServiceBolt11Payload: this._lnurlPayServiceBolt11Payload,
lnurl: this._lnurl,
preimage,
}),
);
}
getSuccessAction() {
return this._lnurlPayServiceBolt11Payload.successAction;
}
getDomain() {
return this._lnurlPayServicePayload.domain;
}
getDescription() {
return this._lnurlPayServicePayload.description;
}
getImage() {
return this._lnurlPayServicePayload.image;
}
getLnurl() {
return this._lnurl;
}
getDisposable() {
return this._lnurlPayServiceBolt11Payload.disposable;
}
getPreimage() {
return this._preimage;
}
static decipherAES(ciphertextBase64, preimageHex, ivBase64) {
const iv = CryptoJS.enc.Base64.parse(ivBase64);
const key = CryptoJS.enc.Hex.parse(preimageHex);
return CryptoJS.AES.decrypt(Buffer.from(ciphertextBase64, 'base64').toString('hex'), key, {
iv,
mode: CryptoJS.mode.CBC,
format: CryptoJS.format.Hex,
}).toString(CryptoJS.enc.Utf8);
}
getCommentAllowed() {
return this?._lnurlPayServicePayload?.commentAllowed ? parseInt(this._lnurlPayServicePayload.commentAllowed) : false;
}
static isLightningAddress(address) {
// ensure only 1 `@` present:
if (address.split('@').length !== 2) return false;
const splitted = address.split('@');
return !!splitted[0].trim() && !!splitted[1].trim();
}
}
async function _fetchGetTor(parsedOnionUrl) {
const torDaemonDisabled = await isTorDaemonDisabled();
if (torDaemonDisabled) {
throw new Error('Tor onion url support disabled');
}
const [baseURI, path] = parsedOnionUrl;
const tor = new torrific.Torsbee({
baseURI,
});
const response = await tor.get(path || '/', {
headers: {
'Access-Control-Allow-Origin': '*',
'Content-Type': 'application/json',
},
});
const json = response.body;
if (typeof json === 'undefined' || response.err) {
throw new Error('Bad response from server: ' + response.err + ' ' + JSON.stringify(response.body));
}
if (json.status === 'ERROR') {
throw new Error('Reply from server: ' + json.reason);
}
return json;
}