Method RecvCryptedPacket

Source/Client/NM_Engine/ClientSocketWorker.cpp:291–423

std::size_t CNetworkClient::RecvCryptedPacket(const void* c_lpData, std::size_t uMaxLength)
{
	if (uMaxLength < TCryptedPacket::size())
		return 0;

	NETWORK_LOG(LL_SYS, "Got crypted packet!");

	if (uMaxLength != TCryptedPacket::size())
	{
		NETWORK_LOG(LL_CRI, "Packet size mismatch! Size: %u Capacity: %u", uMaxLength, TCryptedPacket::size());
		return TCryptedPacket::size();
	}

	auto pCryptedPacket = reinterpret_cast<const TCryptedPacket*>(c_lpData);

	// Magic value check
	if (memcmp(pCryptedPacket->pMagic, gs_pNetworkMagicValue, sizeof(pCryptedPacket->pMagic)))
	{
		NETWORK_LOG(LL_CRI, "Unknown magic value: 0x%X", pCryptedPacket->pMagic);
		return TCryptedPacket::size();
	}

	// Packet sum check
	auto pCorrectChecksum = g_nmApp->NetworkMgrInstance()->CreateChecksum(c_lpData, uMaxLength - (NET_CHECKSUM_LENGTH /* hash */ + NET_CHECKSUM_LENGTH /* sum */));
	if (pCorrectChecksum != pCryptedPacket->ulChecksum)
	{
		NETWORK_LOG(LL_CRI, "Packet checksum mismatch! Current: %p Correct: %p", pCryptedPacket->ulChecksum, pCorrectChecksum);
		return TCryptedPacket::size();
	}

	// Packet hash check
	auto pCorrectPacketHash = XXH32(c_lpData, uMaxLength - NET_CHECKSUM_LENGTH, NET_PACKET_HASH_MAGIC);
	if (pCorrectPacketHash != pCryptedPacket->ulHash)
	{
		NETWORK_LOG(LL_CRI, "Packet hash mismatch! Current: %p Correct: %p", pCryptedPacket->ulHash, pCorrectPacketHash);
		return TCryptedPacket::size();
	}

	NETWORK_LOG(LL_SYS, "Got crypted packet! Original Packet ID: %u Sub Packet ID: %u Crypted packet capacity: %u Crypted packet size: %u",
		pCryptedPacket->uiPacketID, pCryptedPacket->uiDecryptedPacketId, TCryptedPacket::size(), uMaxLength);

	// Packet ID Check
	auto pPacketHandler = m_pHandlers.find(pCryptedPacket->uiDecryptedPacketId);
	if (pPacketHandler == m_pHandlers.end())
	{
		NETWORK_LOG(LL_CRI, "Unknown target packet ID: %u", pCryptedPacket->uiDecryptedPacketId);
		return TCryptedPacket::size();
	}
	NETWORK_LOG(LL_SYS, "Handled packet decrypted id: %u", pCryptedPacket->uiDecryptedPacketId);

	// --

	NETWORK_LOG(LL_SYS, "Decryption has been started. Crpyted data: %p Crypted data size: %u", pCryptedPacket->pContext, pCryptedPacket->ulCryptedSize);

	// Size & sum param check
	if (!pCryptedPacket->ulCryptedSize || !pCryptedPacket->ulDecryptedSize || !pCryptedPacket->ulCryptedSum || !pCryptedPacket->ulDecryptedSum)
	{
		NETWORK_LOG(LL_CRI, "Corrupted crypted data!");