SSH config substitutions

Question

Is it possible to edit substitutions within ssh_config? I know I can match wildcards such as:

Host project*
  HostName %h.domain.com
  User project_user

Used thus:

ssh project000
rsync data project123:~

But are more complex rules possible? How about match to a hostname alias (without explicitly generating every possible combination)?

p    -> project000.domain.com
p1   -> project001.domain.com
p123 -> project123.domain.com

Just in case: I use both bash and zsh

Answer 1

This is how I'm managing this:

My ~/.ssh/config:

Host project*
    ProxyCommand ~/bin/ssh_proxy %h

And ~/bin/ssh_proxy:

#!/bin/zsh

function make_host {
    HOST_NUM=${1[8,999]}
    echo project${(l(3)(0))HOST_NUM}
}

exec nc `make_host $1` 22