Introduce VSOCK link type

[nagy]

This address family is used in communication between virtual machines and their hosts. Advantages include that no virtual ethernet adapter and their respective address configuration and routing need to be setup. Rather, with this new link type, only a single yggdrasil interface can exist inside of the virtual machine.

It can also be used inside of containers. There, the advantage over existing link types like unix sockets include, that no mount point need to be shared with the host and container. This provides more isolation.

More information:

https://man7.org/linux/man-pages/man7/vsock.7.html

https://gist.github.com/nrdmn/7971be650919b112343b1cb2757a3fe6

[neilalexander]

At the moment I am reluctant to add more link types, as I'd actually rather remove quite a few of the link types in v0.6. I'm not really convinced that QUIC, WebSockets or SOCKS have overwhelmingly good reasons to stay either, given they mostly just encourage people to do silly things topology-wise.

[nagy]

Would you be open to external link types for example via a plugin system? For example if you would have an executable program in /usr/bin/yggdrasil-transport-<name> or more likely somewhere in the PATH then the configuration URL like vsock://local:1234 would be passed to it as a first argument to the program yggdrasil-transport-vsock, if it exists. The actual communication happens via stdio. This way we would not need to maintain this dependency in the main repository. People could install new transports via packages via their package managers and we could experiment with new transports in other languages.

, given they mostly just encourage people to do silly things topology-wise.

Of course you would know more about these topology problems than I do, but I want to say that people sometimes rely on these exotic transports to bypass firewalls.

[peigongdsd]

At the moment I am reluctant to add more link types, as I'd actually rather remove quite a few of the link types in v0.6. I'm not really convinced that QUIC, WebSockets or SOCKS have overwhelmingly good reasons to stay either, given they mostly just encourage people to do silly things topology-wise.

Most people do not even know what yggdrasil is. They have never heard of something called a "flat routing scheme". It is quite fair for those who are not so familiar with the mechanism of yggdrasil to take stupid moves, but features are always useful to those who know it, and need it. :)