When ssh-ing into a VM, you generally do not want to log
in as your user from the host. Let's default to the root
user unless a user is explicitly specified.
ssh-generator and ssh-proxy are great features, it is very handy to be
able to do:
ssh vsock/1
But, because of the '/' used as a separator, scp and rsync don't
interpret 'vsock/<CID>' as a hostname, e.g.
$ scp /etc/machine-id vsock/2222:.
cp: cannot create regular file 'vsock/2222:.': No such file or directory
$ rsync /etc/machine-id vsock/2222:.
rsync: [Receiver] change_dir#3 "(...)/vsock" failed: No such file or directory (2)
rsync error: errors selecting input/output files, dirs (code 3) at main.c(829) [Receiver=3.4.1]
An alternative is to use ',' as separator, e.g.
$ scp /etc/machine-id vsock,2222:.
This is what is being suggested here. The names with '/' are kept not to
break anything here.
Others are possible: '%', '=', '#', '@', ':', etc. As mentioned in
commit 0abd510f7f ("ssh-proxy: add ssh ProxyCommand tool that can
connect to AF_UNIX + AF_VSOCK sockets"), it is better to avoid ':' as it
is already taken by SSH itself when doing sftp, and "@" is already taken
for separating the user name. '#' will cause some issues with some
shells like ZSH when quotes are not used.
https://github.com/systemd/systemd/pull/32941
added support for firecracker/cloud-hypervisor and
their unix-domain socket to AF_VSOCK multiplex.
but I forgot to add the pattern in the ssh config drop-in.
fix it now!
This adds a tiny binary that is hooked into SSH client config via
ProxyCommand and which simply connects to an AF_UNIX or AF_VSOCK socket
of choice.
The syntax is as simple as this:
ssh unix/some/path # (this connects to AF_UNIX socket /some/path)
or:
ssh vsock/4711
I used "/" as separator of the protocol ID and the value since ":" is
already taken by SSH itself when doing sftp. And "@" is already taken
for separating the user name.
Daan De Meyer
Yu Watanabe
Matthieu Baerts (NGI0)
Дамјан Георгиевски
Lennart Poettering