Based on suggestions by Jason Grossman and Ed Maste on the mailing list.
We now add a [local su] prefix to the 'su' password prompt (by cheating and
printing it before calling su), and we replace the 'sudo' password prompt
with '[local sudo] Password: ' (by using the little-known and
hopefully-portable -p option).
We no longer call sudo or su if the uid is already 0; otherwise the prefix
on the 'su' prompt would look weird, since su wouldn't ask for a password in
that case.
We don't add a prefix to the ssh password prompt, because it's too hard to
tell if there will *be* an ssh password prompt. But people will probably
assume that the password request is for the server anyway; few people are
likely to think that 'sshuttle -r myhost.com' is going to prompt for the
*local* password.
Of course none of this is a problem on a modern OS, like Debian, that would
say something like "Password for apenwarr@myhost.com:" instead of just
"Password:". MacOS doesn't do that, however, so I assume many other OSes
also don't. Let's try to help them out.
Instead, grab our source code, send it over the link, and have python eval
it and then start the server.py main() function.
Strangely, there's now *less* horrible stuff in ssh.py, because we no longer
have to munge around with the PATH environment variable. And this
significantly reduces the setup required to get sshuttle going.
Based on a suggestion from Wayne Scott.
