[b01lers2020]Welcome to Earth.md

---

首页长这样

害没加载完就die了

document.onkeydown = function(event) {
  event = event || window.event;
  if (event.keyCode == 27) {
    event.preventDefault();
    window.location = "/chase/";
  } else die();
};
function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}
async function dietimer() {
  await sleep(10000);
  die();
}
function die() {
  window.location = "/die/";
}
dietimer();

keyCode = 27是esc，按下即可"escape"✨

---

/chase/

<button onclick="left()">Left</button>
<button onclick="right()">Right</button>

function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

async function dietimer() {
  await sleep(1000);
  die();
}

function die() {
  window.location = "/die/";
}

function left() {
  window.location = "/die/";
}

function leftt() {
  window.location = "/leftt/";
}

function right() {
  window.location = "/die/";
}

dietimer();

横竖都是死，这波直接不装了呗（

---

/leftt/

<button onClick="window.location='/die/'">Take the shot</button>
<!-- <button onClick="window.location='/shoot/'">Take the shot</button> -->

---

/shoot/

震惊，居然没出事

---

/door/

360度开放大门的敌人是吧

<script src="/static/js/door.js"></script>
<button onClick="check_door()">Check</button>

/static/js/door.js

function check_door() {
  var all_radio = document.getElementById("door_form").elements;
  var guess = null;

  for (var i = 0; i < all_radio.length; i++)
    if (all_radio[i].checked) guess = all_radio[i].value;

  rand = Math.floor(Math.random() * 360);
  if (rand == guess) window.location = "/open/";
  else window.location = "/die/";
}

九死一生.jpg

---

/open/

<script src="/static/js/open_sesame.js"></script>
<script>
  open(0);
</script>

/static/js/open_sesame.js

function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

function open(i) {
  sleep(1).then(() => {
    open(i + 1);
  });
  if (i == 4000000000) window.location = "/fight/";
}

---

/fight/

<script src="/static/js/fight.js"></script>
<input type="text" id="action">
<button onClick="check_action()">Fight!</button>

/static/js/fight.js

// Run to scramble original flag
//console.log(scramble(flag, action));
function scramble(flag, key) {
  for (var i = 0; i < key.length; i++) {
    let n = key.charCodeAt(i) % flag.length;
    let temp = flag[i];
    flag[i] = flag[n];
    flag[n] = temp;
  }
  return flag;
}

function check_action() {
  var action = document.getElementById("action").value;
  var flag = ["{hey", "_boy", "aaaa", "s_im", "ck!}", "_baa", "aaaa", "pctf"];

  // TODO: unscramble function
}

flag复原之后是

pctf{hey_boys_im_baaaaaaaaaack!}

#Web #js #代码审计