Add rust kext to the mono repo

windows_kext/driver/README.md

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+# Driver
+
+This is the entry point of the Kernel extension.
+
+## Quick overview
+
+`entry.rs`:
+This file contains the entry point and calling all the needed initialization code. 
+- Setting up the driver object
+- Allocating global state
+
+`fn driver_entry()` -> entry pointer of the driver.
+
+`device.rs`:  
+Holds the global state of the driver.  
+Initialization: Setting up global state, Filter engine and callouts.  
+
+Portmaster communication:
+The communication happens concurrently with the File read/write API.
+That means when Pormtaster sends a command the kernel extension will start to process it and queue the result in the `IOQueue`.
+
+`fn read()` -> called on read request from Portmaster  
+- `IOQueue` holds all the events queued for Portmaster.
+
+Blocks until there is a element that can be poped or shutdown request is sent from Portmaster.
+If there is more then one event in the queue it will write as much as it can in the supplied buffer.
+
+`fn write()` -> called on write request from Portmaster.  
+Used when Portmaster wants to send a command to kernel extension.
+Verdict Response, GetLogs ... (see `protocol` for list of all the commands)
+
+
+## Callouts
+
+`callouts.rs` -> defines the list of all used callouts in the kernel extension. 
+
+ALE (Application Layer Enforcement)
+https://learn.microsoft.com/en-us/windows/win32/fwp/application-layer-enforcement--ale-
+
+### ALE Auth
+
+Connection level filtering. It will make a decision based on the first packet of a connection. Works together with the packet layer to provide firewall functionality.
+- **AleLayerOutboundV4**  
+- **AleLayerInboundV4**  
+- **AleLayerOutboundV6**  
+- **AleLayerInboundV6**  
+
+
+### ALE endpoint / resource assignment and release
+
+Used to listen for event when connection has ended. Does no filtering.
+- **AleEndpointClosureV4, AleEndpointClosureV6** - Triggered when connection to an endpoint has ended. Usually only TCP is triggered.  The triggered connection will be marked for deletion.
+
+- **AleResourceAssignmentV4, AleResourceAssignmentV6** -> only for logging (not used)
+- AleResourceReleaseV4, AleResourceReleaseV6 -> Triggered when port is release from an application. The triggered connection/s will be marked for deletion.
+
+### Stream layer  
+
+This layer works on the application OSI layer. Meaning that only the payload of the TCP/UDP connection will be available.
+It is used for bandwidth monitoring. This functionality is completely separate from the rest of the system so it can be disabled or enabled without affect anything else. 
+
+- **StreamLayerV4, StreamLayerV6** -> For TCP connections 
+- **DatagramDataLayerV4, DatagramDataLayerV6** -> For UDP connections
+
+
+### Packet layer
+
+This layer handled each packet on the network OSI layer. Works together with ALE Auth layer to provide firewall functionality.
+- **IPPacketOutboundV4, IPPacketOutboundV6** -> Triggered on every outbound packet.
+- **IPPacketInboundV4, IPPacketInboundV6** -> Triggered on every inbound packet.