After four years of development, Valve has released GameNetworkingSockets 1.5.0, a library implementing a messaging system over UDP that can be used to implement high-speed and reliable network data exchange in games. The code is written in C++ and licensed under the BSD license.
GameNetworkingSockets implements a TCP-like connection-based protocol over UDP, but focuses on message transmission rather than streaming. Messages can be transmitted over the established communication channel using either guaranteed delivery or faster unreliable transmission.
The protocol supports features such as fragmentation handling, packet reassembly, bandwidth prediction and limiting, P2P communication channel creation, address translator bypass (via WebRTC ICE), and encryption. Data in packets is encrypted using the AES block cipher algorithm, and digital signatures based on Ed25519 elliptic curves are used for key exchange and certificate verification. The key delivery mechanisms and the selection of the initialization vector for each packet are based on the methods used in the QUIC protocol.
Among the changes in the new version:
- The ISteamNetworkingSockets::SendMessages API has been extended to simplify handling of send failures and initiating delivery retries.
- Added new settings for ECN, jitter, local IP detection (IPLocalHost) and disabling authentication (AllowWithoutAuth).
- Added a C-language version of the ISteamNetworkingMessages API.
- The initial version of the binding for the Rust language has been implemented.
- Fixed bugs in the implementation of the P2P mode.
- Automatic correction of situations related to violation of the order of arrival of packets and messages has been implemented.
- Improved integration with CMake and vcpkg toolkits.
- Compatibility with new versions of the protobuf and abseil libraries has been improved.
- Added support for diagnostics via ETW (Event Tracing for Windows).
- Vulnerabilities have been fixed, the details of which are not provided, but judging by the changelog, it concerns an integer overflow in packet sending functions and the possibility of bypassing certificate verification in the CheckCertPOPID function.
Source: opennet.ru
