forked from lolcat/4get
1
0
Fork 0
4get/lib/captcha_gen.php

326 lines
6.8 KiB
PHP

<?php
class captcha{
public function __construct($frontend, $get, $filters, $page, $output){
/*
Validate cookie, if it exists
*/
if(isset($_COOKIE["pass"])){
if(
// check if key is not malformed
preg_match(
'/^c[0-9]+\.[A-Za-z0-9]{20}$/',
$_COOKIE["pass"]
) &&
// does key exist
apcu_exists($_COOKIE["pass"])
){
// exists, increment counter
$inc = apcu_inc($_COOKIE["pass"]);
// we start counting from 1
// when it has been incremented to 102, it has reached
// 100 reqs
if($inc >= 102){
// reached limit, delete and give captcha
apcu_delete($_COOKIE["pass"]);
}else{
// the cookie is OK! dont die() and give results
if($output === true){
$frontend->loadheader(
$get,
$filters,
$page
);
}
return;
}
}
}
if($output === false){
echo json_encode([
"status" => "The \"pass\" token in your cookies is missing or has expired!!"
]);
die();
}
/*
Validate form data
*/
$lines =
explode(
"\r\n",
file_get_contents("php://input")
);
$invalid = false;
$answers = [];
$key = false;
$error = "";
foreach($lines as $line){
$line = explode("=", $line, 2);
if(count($line) !== 2){
$invalid = true;
break;
}
preg_match(
'/^c\[([0-9]+)\]$/',
$line[0],
$regex
);
if(
$line[1] != "on" ||
!isset($regex[0][1])
){
// check if its k
if(
$line[0] == "k" &&
strpos($line[1], "c.") === 0
){
$key = apcu_fetch($line[1]);
apcu_delete($line[1]);
}
break;
}
$regex = (int)$regex[1];
if(
$regex >= 16 ||
$regex <= -1
){
$invalid = true;
break;
}
$answers[] = $regex;
}
if(
!$invalid &&
$key !== false
){
$check = $key[1];
// validate answer
for($i=0; $i<count($key[0]); $i++){
if(!in_array($i, $answers)){
continue;
}
if($key[0][$i][0] == $key[2]){
$check--;
}else{
// got a wrong answer
$check = -1;
break;
}
}
if($check === 0){
// we passed the captcha
// set cookie
$inc = apcu_inc("cookie");
$chars =
array_merge(
range("A", "Z"),
range("a", "z"),
range(0, 9)
);
$c = count($chars) - 1;
$key = "c" . $inc . ".";
for($i=0; $i<20; $i++){
$key .= $chars[random_int(0, $c)];
}
apcu_inc($key, 1, $stupid, 86400);
setcookie(
"pass",
$key,
[
"expires" => time() + 86400, // expires in 24 hours
"samesite" => "Lax",
"path" => "/"
]
);
$frontend->loadheader(
$get,
$filters,
$page
);
return;
}else{
$error = "<div class=\"quote\">You were <a href=\"https://www.youtube.com/watch?v=e1d7fkQx2rk\" target=\"_BLANK\" rel=\"noreferrer nofollow\">kicked out of Mensa.</a> Please try again.</div>";
}
}
/*
Generate random grid data to pass to captcha.php
*/
$dataset = [
["birds", 2263],
["fumo_plushies", 1006],
["minecraft", 848]
];
// get the positions for the answers
// will return between 3 and 6 answer positions
$range = range(0, 15);
$answer_pos = [];
array_splice($range, 0, 1);
for($i=0; $i<random_int(3, 6); $i++){
$answer_pos_tmp =
array_splice(
$range,
random_int(
0,
14 - $i
),
1
);
$answer_pos[] = $answer_pos_tmp[0];
}
// choose a dataset
$choosen = &$dataset[random_int(0, count($dataset) - 1)];
$choices = [];
for($i=0; $i<count($dataset); $i++){
if($dataset[$i][0] == $choosen[0]){
continue;
}
$choices[] = $dataset[$i];
}
// generate grid data
$grid = [];
for($i=0; $i<16; $i++){
if(in_array($i, $answer_pos)){
$grid[] = $choosen;
}else{
$grid[] = $choices[random_int(0, count($choices) - 1)];
}
}
$key = "c." . apcu_inc("captcha_gen", 1) . "." . random_int(0, 100000000);
apcu_store(
$key,
[
$grid,
count($answer_pos),
$choosen[0],
false // has captcha been generated?
],
120 // we give user 2 minutes to get captcha, in case of network error
);
$payload = [
"class" => "",
"right-left" => "",
"right-right" => "",
"left" =>
'<div class="infobox">' .
'<h1>IQ test</h1>' .
'Due to getting hit with 20,000 bot requests per day, I had to put this up. Sorry.<br><br>' .
'Solving this captcha will allow you to make 100 searches today. I will add a way for legit users to bypass the captcha later. Sorry /g/tards!!' .
$error .
'<form method="POST" enctype="text/plain" autocomplete="off">' .
'<div class="captcha-wrapper">' .
'<div class="captcha">' .
'<img src="captcha?k=' . $key . '" alt="Captcha image">' .
'<div class="captcha-controls">' .
'<input type="checkbox" name="c[0]" id="c0">' .
'<label for="c0"></label>' .
'<input type="checkbox" name="c[1]" id="c1">' .
'<label for="c1"></label>' .
'<input type="checkbox" name="c[2]" id="c2">' .
'<label for="c2"></label>' .
'<input type="checkbox" name="c[3]" id="c3">' .
'<label for="c3"></label>' .
'<input type="checkbox" name="c[4]" id="c4">' .
'<label for="c4"></label>' .
'<input type="checkbox" name="c[5]" id="c5">' .
'<label for="c5"></label>' .
'<input type="checkbox" name="c[6]" id="c6">' .
'<label for="c6"></label>' .
'<input type="checkbox" name="c[7]" id="c7">' .
'<label for="c7"></label>' .
'<input type="checkbox" name="c[8]" id="c8">' .
'<label for="c8"></label>' .
'<input type="checkbox" name="c[9]" id="c9">' .
'<label for="c9"></label>' .
'<input type="checkbox" name="c[10]" id="c10">' .
'<label for="c10"></label>' .
'<input type="checkbox" name="c[11]" id="c11">' .
'<label for="c11"></label>' .
'<input type="checkbox" name="c[12]" id="c12">' .
'<label for="c12"></label>' .
'<input type="checkbox" name="c[13]" id="c13">' .
'<label for="c13"></label>' .
'<input type="checkbox" name="c[14]" id="c14">' .
'<label for="c14"></label>' .
'<input type="checkbox" name="c[15]" id="c15">' .
'<label for="c15"></label>' .
'</div>' .
'</div>' .
'</div>' .
'<input type="hidden" name="k" value="' . $key . '">' .
'<input type="submit" value="Check IQ" class="captcha-submit">' .
'</form>' .
'</div>'
];
http_response_code(429); // too many reqs
$frontend->loadheader(
$get,
$filters,
$page
);
echo $frontend->load("search.html", $payload);
die();
}
}