Add legyfetch.js customFetch (#121)

* Add legyfetch.js for LINE API integration

* Remove console logs from resolveToken function

Removed console log statements for token resolution.

Author: Madoa5561

example/legy/legyfetch.js

@@ -0,0 +1,216 @@
+import { BaseClient } from "@evex/linejs/base";
+import { LINEStruct } from "@evex/linejs/thrift";
+import crypto from "node:crypto";
+import https from "node:https";
+import xxhashInit from "xxhash-wasm";
+
+const APP_VER = "26.2.0";
+const SYSTEM_NAME = "Android OS";
+const SYSTEM_VER = "15";
+const X_LINE_APP = `ANDROID\t${APP_VER}\t${SYSTEM_NAME}\t${SYSTEM_VER}`;
+const USER_AGENT = `Line/${APP_VER}`;
+
+// authKeyでもPrimaryTokenでも大丈夫
+const AUTH_KEY = "u***************:++++++++++++++++++";
+
+function createToken(authKey) {
+  const [mid, ...rest] = authKey.split(":");
+  const key = Buffer.from(rest.join(":"), "base64");
+  const iat =
+    Buffer.from(`iat: ${Math.floor(Date.now() / 1000) * 60}\n`, "utf-8").toString("base64") + ".";
+  const digest = crypto.createHmac("sha1", key).update(iat).digest("base64");
+  return `${mid}:${iat}.${digest}`;
+}
+
+function isAlreadyToken(value) {
+  const idx = value.indexOf(":");
+  if (idx === -1) return false;
+  const payload = value.substring(idx + 1);
+  try {
+    const decoded = Buffer.from(payload.split(".")[0], "base64").toString("utf-8");
+    return decoded.startsWith("iat:");
+  } catch {
+    return false;
+  }
+}
+
+function resolveToken(value) {
+  if (isAlreadyToken(value)) {
+    return value;
+  }
+  return createToken(value);
+}
+
+// legy enc
+const LINE_PUBLIC_KEY = `-----BEGIN PUBLIC KEY-----
+MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAsMC6HAYeMq4R59e2yRw6
+W1OWT2t9aepiAp4fbSCXzRj7A29BOAFAvKlzAub4oxN13Nt8dbcB+ICAufyDnN5N
+d3+vXgDxEXZ/sx2/wuFbC3B3evSNKR4hKcs80suRs8aL6EeWi+bAU2oYIc78Bbqh
+Nzx0WCzZSJbMBFw1VlsU/HQ/XdiUufopl5QSa0S246XXmwJmmXRO0v7bNvrxaNV0
+cbviGkOvTlBt1+RerIFHMTw3SwLDnCOolTz3CuE5V2OrPZCmC0nlmPRzwUfxoxxs
+/6qFdpZNoORH/s5mQenSyqPkmH8TBOlHJWPH3eN1k6aZIlK5S54mcUb/oNRRq9wD
+1wIDAQAB
+-----END PUBLIC KEY-----`;
+
+const LEGY_IV = Buffer.from([78, 9, 72, 62, 56, 245, 255, 114, 128, 18, 123, 158, 251, 92, 45, 51]);
+const LEGY_LE = "7";
+const LEGY_LCS_PREFIX = "0008";
+const LEGY_GF_URL = "https://gf.line.naver.jp/enc";
+const leGyAesKey = crypto.randomBytes(16);
+const xLcs = LEGY_LCS_PREFIX + crypto.publicEncrypt(
+  { key: LINE_PUBLIC_KEY, padding: crypto.constants.RSA_PKCS1_OAEP_PADDING, oaepHash: "sha1" },
+  leGyAesKey,
+).toString("base64");
+let xxh = null;
+
+// Serialize
+function encHeaders(headers) {
+  const keys = Object.keys(headers);
+  const parts = [];
+  parts.push(Buffer.from([(keys.length >> 8) & 0xff, keys.length & 0xff]));
+  for (const k of keys) {
+    const kBuf = Buffer.from(k, "ascii");
+    const vBuf = Buffer.from(headers[k], "ascii");
+    parts.push(Buffer.from([(kBuf.length >> 8) & 0xff, kBuf.length & 0xff]));
+    parts.push(kBuf);
+    parts.push(Buffer.from([(vBuf.length >> 8) & 0xff, vBuf.length & 0xff]));
+    parts.push(vBuf);
+  }
+  const body = Buffer.concat(parts);
+  return Buffer.concat([Buffer.from([(body.length >> 8) & 0xff, body.length & 0xff]), body]);
+}
+
+// parse
+function decHeaders(data) {
+  let off = 0;
+  const ri16 = () => { const v = (data[off] << 8) | data[off + 1]; off += 2; return v; };
+  const dataLen = ri16() + 2;
+  const count = ri16();
+  const headers = {};
+  for (let i = 0; i < count; i++) {
+    const kl = ri16(); const k = data.subarray(off, off + kl).toString("ascii"); off += kl;
+    const vl = ri16(); const v = data.subarray(off, off + vl).toString("ascii"); off += vl;
+    headers[k] = v;
+  }
+  return { headers, data: data.subarray(dataLen) };
+}
+
+function pkcs7Unpad(buf) {
+  const n = buf[buf.length - 1];
+  return (n > 0 && n <= 16) ? buf.subarray(0, buf.length - n) : buf;
+}
+
+function pkcs7Pad(buf, bs) {
+  const n = bs - (buf.length % bs);
+  return Buffer.concat([buf, Buffer.alloc(n, n)]);
+}
+
+// AES-128-CBC enc
+function leGyEncrypt(pt) {
+  const c = crypto.createCipheriv("aes-128-cbc", leGyAesKey, LEGY_IV);
+  c.setAutoPadding(true);
+  return Buffer.concat([c.update(pt), c.final()]);
+}
+
+// AES-128-CBC dec
+function leGyDecrypt(ct) {
+  const padded = pkcs7Pad(ct, 16);
+  const d = crypto.createDecipheriv("aes-128-cbc", leGyAesKey, LEGY_IV);
+  d.setAutoPadding(false);
+  const dec = Buffer.concat([d.update(padded), d.final()]);
+  return pkcs7Unpad(dec.subarray(0, dec.length - 16));
+}
+
+// xxHash32 HMAC
+function leGyHmac(key, data, h) {
+  const opad = Buffer.alloc(16);
+  const ipad = Buffer.alloc(16);
+  for (let i = 0; i < 16; i++) {
+    opad[i] = 0x5c ^ key[i];
+    ipad[i] = 0x36 ^ key[i];
+  }
+  const innerHex = (h.h32Raw(Buffer.concat([ipad, data]), 0) >>> 0).toString(16).padStart(8, "0");
+  const outerHex = (h.h32Raw(Buffer.concat([opad, Buffer.from(innerHex, "hex")]), 0) >>> 0).toString(16).padStart(8, "0");
+  return Buffer.from(outerHex, "hex");
+}
+
+async function leGyFetch(request) {
+  if (!xxh) xxh = await xxhashInit();
+  const url = new URL(request.url);
+  const path = url.pathname;
+  const thriftBody = Buffer.from(await request.arrayBuffer());
+  const token = request.headers.get("x-line-access");
+  // legy header
+  const inner = token
+    ? { "x-lt": token, "x-lpqs": path }
+    : { "x-lpqs": path };
+  const plaintext = Buffer.concat([encHeaders(inner), thriftBody]);
+  const leInt = parseInt(LEGY_LE, 10);
+  const fixBytes = (leInt & 4) === 4;
+  let toEncrypt = fixBytes
+    ? Buffer.concat([Buffer.from([leInt]), plaintext])
+    : plaintext;
+  let enc = leGyEncrypt(toEncrypt);
+  if ((leInt & 2) === 2) {
+    enc = Buffer.concat([enc, leGyHmac(leGyAesKey, enc, xxh)]);
+  }
+  // gf.line.naver.jp/enc
+  const { statusCode, responseBody, responseHeaders } = await new Promise((resolve, reject) => {
+    const gfUrl = new URL(LEGY_GF_URL);
+    const req = https.request({
+      hostname: gfUrl.hostname,
+      port: 443,
+      path: gfUrl.pathname,
+      method: "POST",
+      headers: {
+        "x-line-application": X_LINE_APP,
+        "x-le": LEGY_LE,
+        "x-lap": "5",
+        "x-lpv": "1",
+        "x-lcs": xLcs,
+        "User-Agent": USER_AGENT,
+        "content-type": "application/x-thrift; protocol=TBINARY",
+        "x-lal": "ja_JP",
+        "x-lhm": "POST",
+        "accept": "*/*",
+        "accept-encoding": "gzip, deflate",
+        "connection": "keep-alive",
+        "Content-Length": enc.length,
+      },
+    }, (res) => {
+      const chunks = [];
+      res.on("data", (chunk) => chunks.push(chunk));
+      res.on("end", () => resolve({
+        statusCode: res.statusCode,
+        responseBody: Buffer.concat(chunks),
+        responseHeaders: res.headers,
+      }));
+    });
+    req.on("error", reject);
+    req.write(enc);
+    req.end();
+  });
+  if (!responseBody.length) {
+    return new Response(responseBody, { status: statusCode });
+  }
+  // legy dec
+  let dec = leGyDecrypt(responseBody);
+  if (fixBytes) dec = dec.subarray(1);
+  const { headers: innerH, data: thriftData } = decHeaders(dec);
+  const innerStatus = innerH["x-lc"];
+  const httpStatus = (innerStatus && innerStatus !== "200") ? parseInt(innerStatus, 10) : statusCode;
+  return new Response(thriftData, {
+    status: httpStatus,
+    headers: { "content-type": "application/x-thrift" },
+  });
+}
+
+// linejs BaseClient
+const base = new BaseClient({ device: "ANDROID", version: APP_VER, fetch: leGyFetch });
+base.authToken = resolveToken(AUTH_KEY);
+base.request.systemType = X_LINE_APP;
+base.request.userAgent = USER_AGENT;
+base.talk.requestPath = "/S3";
+base.talk.protocolType = 3;
+
+export { base, LINEStruct };