Add internal reverse chnroute build

Build/build-internal-reverse-chn-cidr.js

@@ -0,0 +1,48 @@
+// @ts-check
+const { fetchRemoteTextAndCreateReadlineInterface } = require('./lib/fetch-remote-text-by-line');
+const { processLine } = require('./lib/process-line');
+const path = require('path');
+const fse = require('fs-extra');
+const fs = require('fs');
+
+const RESERVED_IPV4_CIDR = [
+  '0.0.0.0/8',
+  '10.0.0.0/8',
+  '100.64.0.0/10',
+  '127.0.0.0/8',
+  '169.254.0.0/16',
+  '172.16.0.0/12',
+  '192.0.0.0/24',
+  '192.0.2.0/24',
+  '192.168.0.0/16',
+  '198.18.0.0/15',
+  '198.51.100.0/24',
+  '203.0.113.0/24',
+  '224.0.0.0/4',
+  '233.252.0.0/24',
+  '240.0.0.0/4'
+];
+
+(async () => {
+  const { exclude } = await import('cidr-tools-wasm');
+
+  /** @type {Set<string>} */
+  const cidr = new Set();
+  for await (const line of await fetchRemoteTextAndCreateReadlineInterface('https://raw.githubusercontent.com/misakaio/chnroutes2/master/chnroutes.txt')) {
+    const l = processLine(line);
+    if (l) {
+      cidr.add(l);
+    }
+  }
+
+  const reversedCidr = exclude(
+    ['0.0.0.0/0'],
+    RESERVED_IPV4_CIDR.concat(Array.from(cidr))
+  );
+
+  await fse.ensureDir(path.resolve(__dirname, '../List/internal'));
+  await fs.promises.writeFile(
+    path.resolve(__dirname, '../List/internal/cdn.txt'),
+    `${reversedCidr.join('\n')}\n`
+  );
+})();