stream: encrypt cached stream data & clean up related modules

also limited CORS methods to GET and POST

src/modules/sub/crypto.js

@@ -1,5 +1,26 @@
-import { createHmac } from "crypto";
+import { createHmac, createCipheriv, createDecipheriv, scryptSync } from "crypto";
+
+const algorithm = "aes256"
+const keyLength = 32;
 
 export function sha256(str, salt) {
-    return createHmac("sha256", salt).update(str).digest("hex");
+    return createHmac("sha256", salt).update(str).digest("base64");
+}
+
+export function encryptStream(str, iv, secret) {
+    const buff = Buffer.from(JSON.stringify(str), "utf-8");
+
+    const key = scryptSync(Buffer.from(secret, "base64"), "salt", keyLength);
+    const cipher = createCipheriv(algorithm, key, Buffer.from(iv, "base64"));
+
+    return Buffer.from(cipher.update(buff, "utf8", "binary") + cipher.final("binary"), "binary");
+}
+
+export function decryptStream(buf, iv, secret) {
+    const buff = Buffer.from(buf, "binary");
+
+    const key = scryptSync(Buffer.from(secret, "base64"), "salt", keyLength);
+    const decipher = createDecipheriv(algorithm, key, Buffer.from(iv, "base64"));
+
+    return decipher.update(buff, "binary", "utf8") + decipher.final("utf8");
 }