MadelineProto/src/danog/MadelineProto/SecretChats/SeqNoHandler.php

88 lines
4.2 KiB
PHP

<?php
/**
* SeqNoHandler module.
*
* This file is part of MadelineProto.
* MadelineProto is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
* MadelineProto is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
* See the GNU Affero General Public License for more details.
* You should have received a copy of the GNU General Public License along with MadelineProto.
* If not, see <http://www.gnu.org/licenses/>.
*
* @author Daniil Gentili <daniil@daniil.it>
* @copyright 2016-2020 Daniil Gentili <daniil@daniil.it>
* @license https://opensource.org/licenses/AGPL-3.0 AGPLv3
*
* @link https://docs.madelineproto.xyz MadelineProto documentation
*/
namespace danog\MadelineProto\SecretChats;
use danog\MadelineProto\Logger;
/**
* Manages sequence numbers.
*/
trait SeqNoHandler
{
private function checkSecretInSeqNo($chat_id, $seqno): \Generator
{
$seqno = ($seqno - $this->secret_chats[$chat_id]['out_seq_no_x']) / 2;
$last = 0;
foreach ($this->secret_chats[$chat_id]['incoming'] as $message) {
if (isset($message['decrypted_message']['in_seq_no'])) {
if (($message['decrypted_message']['in_seq_no'] - $this->secret_chats[$chat_id]['out_seq_no_x']) / 2 < $last) {
$this->logger->logger("Discarding secret chat $chat_id, in_seq_no is not increasing", Logger::LEVEL_FATAL);
yield from $this->discardSecretChat($chat_id);
throw new \danog\MadelineProto\SecurityException('in_seq_no is not increasing');
}
$last = ($message['decrypted_message']['in_seq_no'] - $this->secret_chats[$chat_id]['out_seq_no_x']) / 2;
}
}
if ($seqno > $this->secret_chats[$chat_id]['out_seq_no'] + 1) {
$this->logger->logger("Discarding secret chat $chat_id, in_seq_no is too big", Logger::LEVEL_FATAL);
yield from $this->discardSecretChat($chat_id);
throw new \danog\MadelineProto\SecurityException('in_seq_no is too big');
}
return true;
}
private function checkSecretOutSeqNo($chat_id, $seqno): \Generator
{
$seqno = ($seqno - $this->secret_chats[$chat_id]['in_seq_no_x']) / 2;
$C = 0;
foreach ($this->secret_chats[$chat_id]['incoming'] as $message) {
if (isset($message['decrypted_message']['out_seq_no']) && $C < $this->secret_chats[$chat_id]['in_seq_no']) {
$temp = ($message['decrypted_message']['out_seq_no'] - $this->secret_chats[$chat_id]['in_seq_no_x']) / 2;
if ($temp !== $C) {
$this->logger->logger("Discarding secret chat $chat_id, out_seq_no hole: should be $C, is $temp", Logger::LEVEL_FATAL);
yield from $this->discardSecretChat($chat_id);
throw new \danog\MadelineProto\SecurityException("out_seq_no hole: should be $C, is $temp");
}
$C++;
}
}
//$this->logger->logger($C, $seqno);
if ($seqno < $C) {
// <= C
$this->logger->logger('WARNING: dropping repeated message with seqno '.$seqno);
return false;
}
if ($seqno > $C) {
// > C+1
$this->logger->logger("Discarding secret chat $chat_id, out_seq_no gap detected: ($seqno > $C)", Logger::LEVEL_FATAL);
yield from $this->discardSecretChat($chat_id);
throw new \danog\MadelineProto\SecurityException('WARNING: out_seq_no gap detected ('.$seqno.' > '.$C.')!');
}
return true;
}
private function generateSecretInSeqNo($chat)
{
return $this->secret_chats[$chat]['layer'] > 8 ? $this->secret_chats[$chat]['in_seq_no'] * 2 + $this->secret_chats[$chat]['in_seq_no_x'] : -1;
}
private function generateSecretOutSeqNo($chat)
{
return $this->secret_chats[$chat]['layer'] > 8 ? $this->secret_chats[$chat]['out_seq_no'] * 2 + $this->secret_chats[$chat]['out_seq_no_x'] : -1;
}
}