DIGITAL LIB UEH DOWNLOAD SCRIPT

enhance_script.js

// =============================================
// Paste this in the browser console at:
// https://digital.lib.ueh.edu.vn/
// =============================================

async function sha256(message) {
  const msgUint8 = new TextEncoder().encode(message);
  const hashBuffer = await crypto.subtle.digest('SHA-256', msgUint8);
  const hashArray = Array.from(new Uint8Array(hashBuffer));
  return hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
}

const params = new URLSearchParams(window.location.search);
const doc = params.get('doc');
const bitsid = params.get('bitsid');

if (!(doc && bitsid)) throw new Error("Missing 'doc' or 'bitsid' URL parameter.");

const T = doc.split("");
const downloadLink = `/dspace/pdf/${T[0]}${T[1]}/${T[2]}${T[3]}/${T[4]}${T[5]}/${bitsid}.pdf`;

// If you set window.password yourself, that takes precedence.
// Otherwise compute the site’s password scheme.
const computed = await sha256("Dlc0rp#!234" + bitsid);
const pw = (typeof window.password === 'string' && window.password.length) ? window.password : computed;
console.log('Using password:', pw === computed ? '(computed sha256)' : '(manual override)');

async function loadQpdfWasm() {
  const mjs = 'https://cdn.jsdelivr.net/npm/@jspawn/qpdf-wasm/qpdf.mjs';
  const wasm = 'https://cdn.jsdelivr.net/npm/@jspawn/qpdf-wasm/qpdf.wasm';
  const mod = await import(mjs);
  const createModule = mod.default || mod;
  return createModule({ noInitialRun: true, locateFile: () => wasm });
}

async function fetchPdfBytes(url) {
  const res = await fetch(url, { credentials: 'same-origin', headers: { 'Accept': 'application/pdf' } });
  if (!res.ok) throw new Error(`Failed to fetch PDF (${res.status})`);
  return new Uint8Array(await res.arrayBuffer());
}

async function decryptPdfBytes(encBytes, pw) {
  const qpdf = await loadQpdfWasm();
  const inPath = '/input.pdf';
  const outPath = '/output.pdf';
  qpdf.FS.writeFile(inPath, encBytes);

  // Decrypt and linearize (clean rewrite).
  // If the file is not encrypted, this still rewrites it neatly.
  try {
    qpdf.callMain([`--password=${pw}`, '--decrypt', '--linearize', inPath, outPath]);
  } catch (e) {
    throw new Error('QPDF failed to decrypt/linearize. Check the password and encryption state.\n' + (e?.message || e));
  }
  return qpdf.FS.readFile(outPath);
}

function saveBytes(bytes, filename) {
  const blob = new Blob([bytes], { type: 'application/pdf' });
  const url = URL.createObjectURL(blob);
  const a = document.createElement('a');
  a.href = url;
  a.download = filename;
  document.body.appendChild(a);
  a.click();
  document.body.removeChild(a);
  setTimeout(() => URL.revokeObjectURL(url), 10_000);
}

(async () => {
  try {
    console.log('Fetching:', downloadLink);
    const enc = await fetchPdfBytes(downloadLink);
    console.log('Bytes fetched:', enc.byteLength);

    console.log('Decrypting with QPDF (WASM)…');
    const dec = await decryptPdfBytes(enc, pw);
    console.log('Unlocked bytes:', dec.byteLength);

    const outName = `${bitsid}-unlocked.pdf`;
    saveBytes(dec, outName);
    console.log('✅ Saved:', outName);
  } catch (err) {
    console.error('❌ Error:', err);
  }
})();

script.js

// =============================================
//  💀 Hack the Library 💀
//  Paste this in the browser console at:
//  https://digital.lib.ueh.edu.vn/
//  Knowledge wants to be free.
// =============================================
// Function to compute the SHA256 hash of a message.
async function sha256(message) {
  // Encode the message string to a Uint8Array.
  const msgUint8 = new TextEncoder().encode(message); 
  // Get the hash as an ArrayBuffer.
  const hashBuffer = await crypto.subtle.digest('SHA-256', msgUint8);
  // Convert the hash buffer to an array of bytes.
  const hashArray = Array.from(new Uint8Array(hashBuffer));
  // Convert each byte to a two-digit hexadecimal string and join them.
  const hashHex = hashArray.map(b => b.toString(16).padStart(2, '0')).join('');
  return hashHex;
}

// Get URL parameters from the current page.
const params = new URLSearchParams(window.location.search);
const doc = params.get('doc');
const bitsid = params.get('bitsid');

// Check if both parameters exist before proceeding.
if (doc && bitsid) {
  // Construct the download link.
  const T = doc.split("");
  const downloadLink = `/dspace/pdf/${T[0]}${T[1]}/${T[2]}${T[3]}/${T[4]}${T[5]}/${bitsid}.pdf`;

  // Compute the password.
  const password = await sha256("Dlc0rp#!234" + bitsid);

  console.log('PASSWORD:', password);

  // Function to trigger the download.
  function downloadFile(url, filename) {
    const a = document.createElement('a');
    a.href = url;
    a.download = filename;
    document.body.appendChild(a); // Append the link to the body.
    a.click(); // Programmatically click the link.
    document.body.removeChild(a); // Clean up the DOM.
  }

  // Automatically trigger the download.
  downloadFile(downloadLink, `${bitsid}.pdf`);
} else {
  console.error("Missing 'doc' or 'bitsid' URL parameter.");
}