[deno] AES crypto CBC

generate.ts

import { writeFileStr, readFileStr } from "https://deno.land/std/fs/mod.ts";
import { crypto } from "https://deno.land/std/crypto/mod.ts";

async function encryptAndSave(results: any[], keyFile: string, dataFile: string) {
  // Generate a random 256-bit (32 bytes) key and IV
  const key = crypto.getRandomValues(new Uint8Array(32)); // AES-256
  const iv = crypto.getRandomValues(new Uint8Array(16)); // AES block size

  // Convert results to JSON string
  const resultsJSON = JSON.stringify(results);
  const encoder = new TextEncoder();
  const encodedResults = encoder.encode(resultsJSON);

  // Encrypt the JSON data
  const cipherText = new Uint8Array(
    await crypto.subtle.encrypt(
      { name: "AES-CBC", iv },
      await crypto.subtle.importKey("raw", key, "AES-CBC", false, ["encrypt"]),
      encodedResults
    )
  );

  // Save the key and IV as a base64 encoded JSON
  const keyData = {
    key: btoa(String.fromCharCode(...key)),
    iv: btoa(String.fromCharCode(...iv)),
  };
  await writeFileStr(keyFile, JSON.stringify(keyData));

  // Save the encrypted data as base64
  await writeFileStr(dataFile, btoa(String.fromCharCode(...cipherText)));

  console.log("Data encrypted and saved successfully.");
}

// Usage
const results = [{ id: 1, value: "example" }, { id: 2, value: "test" }];
await encryptAndSave(results, "key.json", "data.enc");

retrieve.ts

async function decryptAndRetrieve(keyFile: string, dataFile: string): Promise<any[]> {
  // Read the key and IV from the file
  const keyData = JSON.parse(await readFileStr(keyFile));
  const key = Uint8Array.from(atob(keyData.key), (c) => c.charCodeAt(0));
  const iv = Uint8Array.from(atob(keyData.iv), (c) => c.charCodeAt(0));

  // Read the encrypted data
  const encryptedData = Uint8Array.from(
    atob(await readFileStr(dataFile)),
    (c) => c.charCodeAt(0)
  );

  // Decrypt the data
  const decrypted = new Uint8Array(
    await crypto.subtle.decrypt(
      { name: "AES-CBC", iv },
      await crypto.subtle.importKey("raw", key, "AES-CBC", false, ["decrypt"]),
      encryptedData
    )
  );

  // Decode the decrypted data back to JSON
  const decoder = new TextDecoder();
  const resultsJSON = decoder.decode(decrypted);
  return JSON.parse(resultsJSON);
}

// Usage
const decryptedResults = await decryptAndRetrieve("key.json", "data.enc");
console.log("Decrypted Results:", decryptedResults);