/check_authorization.php

## check_authorization.php
<?php

define('BOT_TOKEN', 'XXXXXXXX:XXXXXXXXXXXXXXXXXXXXXXXX'); // place bot token of your bot here

function checkTelegramAuthorization($auth_data) {
  $check_hash = $auth_data['hash'];
  unset($auth_data['hash']);
  $data_check_arr = [];
  foreach ($auth_data as $key => $value) {
    $data_check_arr[] = $key . '=' . $value;
  }
  sort($data_check_arr);
  $data_check_string = implode("\n", $data_check_arr);
  $secret_key = hash('sha256', BOT_TOKEN, true);
  $hash = hash_hmac('sha256', $data_check_string, $secret_key);
  if (strcmp($hash, $check_hash) !== 0) {
    throw new Exception('Data is NOT from Telegram');
  }
  if ((time() - $auth_data['auth_date']) > 86400) {
    throw new Exception('Data is outdated');
  }
  return $auth_data;
}

function saveTelegramUserData($auth_data) {
  $auth_data_json = json_encode($auth_data);
  setcookie('tg_user', $auth_data_json);
}


try {
  $auth_data = checkTelegramAuthorization($_GET);
  saveTelegramUserData($auth_data);
} catch (Exception $e) {
  die ($e->getMessage());
}

header('Location: login_example.php');

?>

## login_example.php
<?php

define('BOT_USERNAME', 'XXXXXXXXXX'); // place username of your bot here

function getTelegramUserData() {
  if (isset($_COOKIE['tg_user'])) {
    $auth_data_json = urldecode($_COOKIE['tg_user']);
    $auth_data = json_decode($auth_data_json, true);
    return $auth_data;
  }
  return false;
}

if ($_GET['logout']) {
  setcookie('tg_user', '');
  header('Location: login_example.php');
}

$tg_user = getTelegramUserData();
if ($tg_user !== false) {
  $first_name = htmlspecialchars($tg_user['first_name']);
  $last_name = htmlspecialchars($tg_user['last_name']);
  if (isset($tg_user['username'])) {
    $username = htmlspecialchars($tg_user['username']);
    $html = "<h1>Hello, <a href=\"https://t.me/{$username}\">{$first_name} {$last_name}</a>!</h1>";
  } else {
    $html = "<h1>Hello, {$first_name} {$last_name}!</h1>";
  }
  if (isset($tg_user['photo_url'])) {
    $photo_url = htmlspecialchars($tg_user['photo_url']);
    $html .= "<img src=\"{$photo_url}\">";
  }
  $html .= "<p><a href=\"?logout=1\">Log out</a></p>";
} else {
  $bot_username = BOT_USERNAME;
  $html = <<<HTML
<h1>Hello, anonymous!</h1>
<script async src="https://telegram.org/js/telegram-widget.js?2" data-telegram-login="{$bot_username}" data-size="large" data-auth-url="check_authorization.php"></script>
HTML;
}


  echo <<<HTML
<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Login Widget Example</title>
  </head>
  <body><center>{$html}</center></body>
</html>
HTML;

?>
	<?php

	define('BOT_TOKEN', 'XXXXXXXX:XXXXXXXXXXXXXXXXXXXXXXXX'); // place bot token of your bot here

	function checkTelegramAuthorization($auth_data) {
	$check_hash = $auth_data['hash'];
	unset($auth_data['hash']);
	$data_check_arr = [];
	foreach ($auth_data as $key => $value) {
	$data_check_arr[] = $key . '=' . $value;
	}
	sort($data_check_arr);
	$data_check_string = implode("\n", $data_check_arr);
	$secret_key = hash('sha256', BOT_TOKEN, true);
	$hash = hash_hmac('sha256', $data_check_string, $secret_key);
	if (strcmp($hash, $check_hash) !== 0) {
	throw new Exception('Data is NOT from Telegram');
	}
	if ((time() - $auth_data['auth_date']) > 86400) {
	throw new Exception('Data is outdated');
	}
	return $auth_data;
	}

	function saveTelegramUserData($auth_data) {
	$auth_data_json = json_encode($auth_data);
	setcookie('tg_user', $auth_data_json);
	}


	try {
	$auth_data = checkTelegramAuthorization($_GET);
	saveTelegramUserData($auth_data);
	} catch (Exception $e) {
	die ($e->getMessage());
	}

	header('Location: login_example.php');

	?>
	<?php

	define('BOT_USERNAME', 'XXXXXXXXXX'); // place username of your bot here

	function getTelegramUserData() {
	if (isset($_COOKIE['tg_user'])) {
	$auth_data_json = urldecode($_COOKIE['tg_user']);
	$auth_data = json_decode($auth_data_json, true);
	return $auth_data;
	}
	return false;
	}

	if ($_GET['logout']) {
	setcookie('tg_user', '');
	header('Location: login_example.php');
	}

	$tg_user = getTelegramUserData();
	if ($tg_user !== false) {
	$first_name = htmlspecialchars($tg_user['first_name']);
	$last_name = htmlspecialchars($tg_user['last_name']);
	if (isset($tg_user['username'])) {
	$username = htmlspecialchars($tg_user['username']);
	$html = "<h1>Hello, <a href=\"https://t.me/{$username}\">{$first_name} {$last_name}</a>!</h1>";
	} else {
	$html = "<h1>Hello, {$first_name} {$last_name}!</h1>";
	}
	if (isset($tg_user['photo_url'])) {
	$photo_url = htmlspecialchars($tg_user['photo_url']);
	$html .= "<img src=\"{$photo_url}\">";
	}
	$html .= "<p><a href=\"?logout=1\">Log out</a></p>";
	} else {
	$bot_username = BOT_USERNAME;
	$html = <<<HTML
	<h1>Hello, anonymous!</h1>
	<script async src="https://telegram.org/js/telegram-widget.js?2" data-telegram-login="{$bot_username}" data-size="large" data-auth-url="check_authorization.php"></script>
	HTML;
	}


	echo <<<HTML
	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>Login Widget Example</title>
	</head>
	<body><center>{$html}</center></body>
	</html>
	HTML;

	?>