WinDivert 2.2: Windows Packet Divert

1. Introduction

Windows Packet Divert (WinDivert) is a user-mode packet interception library
for Windows 7, Windows 8 and Windows 10.

WinDivert enables user-mode capturing/modifying/dropping of network packets
sent to/from the Windows network stack. In summary, WinDivert can:
- capture network packets
- filter/drop network packets
- sniff network packets
- (re)inject network packets
- modify network packets
WinDivert can be used to implement user-mode packet filters, sniffers,
firewalls, NATs, VPNs, IDSs, tunneling applications, etc..

WinDivert supports the following features:
- packet interception, sniffing, or dropping modes
- support for loopback (localhost) traffic
- full IPv6 support
- network layer
- simple yet powerful API
- high-level filtering language
- filter priorities
- freely available under the terms of the GNU Lesser General Public
License (LGPLv3)

For more information see doc/windivert.html

2. Architecture

The basic architecture of WinDivert is as follows:

                          +-----------------+, +------->, PROGRAM, --------+, (WinDivert.dll), +-----------------+, (3) re-injected, (2a) matching packet, packet, [user mode], ...................., ..................................., ...................

[kernel mode], +---------------+ +----------------->
(1) packet, (2b) non-matching packet
------------>, WinDivert.sys, -------------------------------------------->, +---------------+

The WinDivert.sys driver is installed below the Windows network stack. The
following actions occur:

(1) A new packet enters the network stack and is intercepted by WinDivert.sys
(2a) If the packet matches the PROGRAM-defined filter, it is diverted. The
PROGRAM can then read the packet using a call to WinDivertRecv().
(2b) If the packet does not match the filter, the packet continues as normal.
(3) PROGRAM either drops, modifies, or re-injects the packet. PROGRAM can
re-inject the (modified) using a call to WinDivertSend().

3. License

WinDivert is dual-licensed under your choice of the GNU Lesser General Public
License (LGPL) Version 3 or the GNU General Public License (GPL) Version 2.
See the LICENSE file for more information.

4. About

WinDivert was written by basil.

For further information, or bug reports, please contact:

basil@reqrypt.org

The homepage for WinDivert is:

https://reqrypt.org/windivert.html

The source code for WinDivert is hosted by GitHub at:

https://github.com/basil00/Divert