Re: Lua as a scripting language in NetBSD

[Thor Lancelot Simon <tls%panix.com@localhost>]

On Sun, Oct 18, 2009 at 08:29:02PM +0300, Antti Kantee wrote:
> 
> I am opposed to "wishful thinking" additions to the base system without
> any real evidence of the actual usefulness.

You want an example application?  Some of mine are proprietary so I can't
share their details right now.  But here is one which I think has pretty
general appeal.  I would like to use Lua, in the kernel, to implement
stateful application-layer packet filtering and redirection, using our
existing packet filter hooks and (in some cases) ipfilter's "call" action.

Lua is fast enough to do this for many small firewalls, far safer than
using C code, and far more flexible than the canned types of packet
matchers and actions offered by ipfilter or pf.  And it interfaces neatly
with C code such that it's easy to write tiny shims which hook it up to
our network stack using the existing packet filter hooks.

Basically, I want a small, fast, safe language for data filtering and
manipulation in the kernel.  Lua is the best candidate I can see right
now.

-- 
Thor Lancelot Simon                                        
tls%rek.tjls.com@localhost
    "Even experienced UNIX users occasionally enter rm *.* at the UNIX
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