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| 'use strict'
/** * static files (404.html, sw.js, conf.js) */const ASSET_URL = 'https://etherdream.github.io/jsproxy'const JS_VER = 10const MAX_RETRY = 1/** @type {RequestInit} */const PREFLIGHT_INIT = { status: 204, headers: new Headers({ 'access-control-allow-origin': '*', 'access-control-allow-methods': 'GET,POST,PUT,PATCH,TRACE,DELETE,HEAD,OPTIONS', 'access-control-max-age': '1728000', }),}/** * @param {any} body * @param {number} status * @param {Object<string, string>} headers */function makeRes(body, status = 200, headers = {}) { headers['--ver'] = JS_VER headers['access-control-allow-origin'] = '*' return new Response(body, {status, headers})}/** * @param {string} urlStr */function newUrl(urlStr) { try { return new URL(urlStr) } catch (err) { return null }}addEventListener('fetch', e => { const ret = fetchHandler(e) .catch(err => makeRes('cfworker error:\n' + err.stack, 502)) e.respondWith(ret)})/** * @param {FetchEvent} e */async function fetchHandler(e) { const req = e.request const urlStr = req.url const urlObj = new URL(urlStr) const path = urlObj.href.substr(urlObj.origin.length) if (urlObj.protocol === 'http:') { urlObj.protocol = 'https:' return makeRes('', 301, { 'strict-transport-security': 'max-age=99999999; includeSubDomains; preload', 'location': urlObj.href, }) } if (path.startsWith('/http/')) { return httpHandler(req, path.substr(6)) } switch (path) { case '/http': return makeRes('请更新 cfworker 到最新版本!') case '/ws': return makeRes('not support', 400) case '/works': return makeRes('it works') default: // static files return fetch(ASSET_URL + path) }}/** * @param {Request} req * @param {string} pathname */function httpHandler(req, pathname) { const reqHdrRaw = req.headers if (reqHdrRaw.has('x-jsproxy')) { return Response.error() } // preflight if (req.method === 'OPTIONS' && reqHdrRaw.has('access-control-request-headers') ) { return new Response(null, PREFLIGHT_INIT) } let acehOld = false let rawSvr = '' let rawLen = '' let rawEtag = '' const reqHdrNew = new Headers(reqHdrRaw) reqHdrNew.set('x-jsproxy', '1') // 此处逻辑和 http-dec-req-hdr.lua 大致相同 // https://github.com/EtherDream/jsproxy/blob/master/lua/http-dec-req-hdr.lua const refer = reqHdrNew.get('referer') const query = refer.substr(refer.indexOf('?') + 1) if (!query) { return makeRes('missing params', 403) } const param = new URLSearchParams(query) for (const [k, v] of Object.entries(param)) { if (k.substr(0, 2) === '--') { // 系统信息 switch (k.substr(2)) { case 'aceh': acehOld = true break case 'raw-info': [rawSvr, rawLen, rawEtag] = v.split('|') break } } else { // 还原 HTTP 请求头 if (v) { reqHdrNew.set(k, v) } else { reqHdrNew.delete(k) } } } if (!param.has('referer')) { reqHdrNew.delete('referer') } // cfworker 会把路径中的 `//` 合并成 `/` const urlStr = pathname.replace(/^(https?):\/+/, '$1://') const urlObj = newUrl(urlStr) if (!urlObj) { return makeRes('invalid proxy url: ' + urlStr, 403) } /** @type {RequestInit} */ const reqInit = { method: req.method, headers: reqHdrNew, redirect: 'manual', } if (req.method === 'POST') { reqInit.body = req.body } return proxy(urlObj, reqInit, acehOld, rawLen, 0)}/** * * @param {URL} urlObj * @param {RequestInit} reqInit * @param {number} retryTimes */async function proxy(urlObj, reqInit, acehOld, rawLen, retryTimes) { const res = await fetch(urlObj.href, reqInit) const resHdrOld = res.headers const resHdrNew = new Headers(resHdrOld) let expose = '*' for (const [k, v] of resHdrOld.entries()) { if (k === 'access-control-allow-origin' || k === 'access-control-expose-headers' || k === 'location' || k === 'set-cookie' ) { const x = '--' + k resHdrNew.set(x, v) if (acehOld) { expose = expose + ',' + x } resHdrNew.delete(k) } else if (acehOld && k !== 'cache-control' && k !== 'content-language' && k !== 'content-type' && k !== 'expires' && k !== 'last-modified' && k !== 'pragma' ) { expose = expose + ',' + k } } if (acehOld) { expose = expose + ',--s' resHdrNew.set('--t', '1') } // verify if (rawLen) { const newLen = resHdrOld.get('content-length') || '' const badLen = (rawLen !== newLen) if (badLen) { if (retryTimes < MAX_RETRY) { urlObj = await parseYtVideoRedir(urlObj, newLen, res) if (urlObj) { return proxy(urlObj, reqInit, acehOld, rawLen, retryTimes + 1) } } return makeRes(res.body, 400, { '--error': `bad len: ${newLen}, except: ${rawLen}`, 'access-control-expose-headers': '--error', }) } if (retryTimes > 1) { resHdrNew.set('--retry', retryTimes) } } let status = res.status resHdrNew.set('access-control-expose-headers', expose) resHdrNew.set('access-control-allow-origin', '*') resHdrNew.set('--s', status) resHdrNew.set('--ver', JS_VER) resHdrNew.delete('content-security-policy') resHdrNew.delete('content-security-policy-report-only') resHdrNew.delete('clear-site-data') if (status === 301 || status === 302 || status === 303 || status === 307 || status === 308 ) { status = status + 10 } return new Response(res.body, { status, headers: resHdrNew, })}/** * @param {URL} urlObj */function isYtUrl(urlObj) { return ( urlObj.host.endsWith('.googlevideo.com') && urlObj.pathname.startsWith('/videoplayback') )}/** * @param {URL} urlObj * @param {number} newLen * @param {Response} res */async function parseYtVideoRedir(urlObj, newLen, res) { if (newLen > 2000) { return null } if (!isYtUrl(urlObj)) { return null } try { const data = await res.text() urlObj = new URL(data) } catch (err) { return null } if (!isYtUrl(urlObj)) { return null } return urlObj}
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