This document describes the high-level architecture of this project
If you want to familiarize yourself with the code base and generally how it works, this is a good place to be.
main.go loads cmd/root.go which runs the function Root. Root
starts all the magic. It does cli logic and program initialization of
state. Root also spawns the 2 major components, ethrouter and tunrouter. Think of tunrouter and ethrouter as the "supervisors" in the actor pattern. They don't do much super vising but they do some small management and error propegation.
Each tunrouter and ethrouter spawn their submodules. Submodules are either a reader or writer. Each are actions relating to resource stream management. Lets look at a diagram.
Ok that's a lot. Lets start where we left off. main spawns Root. Root spawns tunrouter and ethrouter. tunrouter spawns tunrouter.reader and tunrouter writer. ethrouter spawns ethrouter.reader and ethrouter.writer.
Each router is responsible for resource routing (one of literal network routing). Before we do that, lets look at a simplified diagram.
The big arrows are messages, in this case its channels.
Each thin line is either a read or a write.
readers do more processing so the writers can be quick writing as its a blocking operation.
This is achieved by an async patter.
readers essentially read from a resource, spawn a channel with a copy of the read buffer, do processing of that data, then write to a channel.
writers essentially read from channel and immediate write.
This completely ensures quick writes and async data processing.
In this case ethrouter.reader reads from a socket, then decrypts and decompresses the VPN packets, then writes to tunrouter.writer.
tunrouter.writer reads from channel and writes to the tun interface.
tunrouter.reader reads from the tun interface, compresses and encrypts the tun packets. After, it routes the traffic and writes to ethrouter.writer.
ethrouter.writer reads from channel and sends to routed host on socket.
<file name> for a file name
<folder name>/ for a folder
<folder name>/<file name> for a file within a folder
Main function where everything gets started.
Command line interface package where command line interface parsing stuff lives. We call this package shanty like sea shanty.
Root command file which gets instantiated by main.go
Manages global config thats set at initialization time.
Home of tun. This manages the tun interface. It brings it up, configures it, and kills it.
Home of translation. This turns tun packets into VPN packets and vice versa. It both compresses and encrypts and decrypts and decompresses.
Home of ethrouter
Basic supervisor of ethrouter.writer and ethrouter.reader
home of ethrouter.writer
home of ethrouter.reader
Home of tunrouter
Basic supervisor of tunrouter.writer and tunrouter.reader
home of tunrouter.writer
home of tunrouter.reader