Re: nftables: parser conflict between tokens & symbols

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Fri, Jun 26, 2015 at 02:44:23PM +0200, Balazs Scheidler wrote:
> Hi,
> 
> I've noticed that our set of keywords in nftables is pretty rich and
> this can cause conflicts in the grammar when a keyword is also used
> as a symbol.
> 
> For instance, we do have a "redirect" expression and "redirect" as
> a word is also used as an ICMP message type.
> 
> # here is the redirect expression in action, which works:
> $ nft add rule tcp dport 80 redirect to 8080
> 
> # here's an ICMP rule that works
> $ nft add rule filter input icmp type echo-request accept
> 
> # here's an ICMP rule that should work, but it doesn't
> $ nft add rule filter input icmp type redirect accept
> 
> The root cause is that "redirect" is now recognized as a token, whereas the
> icmp type is expecting a STRING token.
> 
> I have tried to solve this but the idea I had didn't work out, and I don't
> really have more time now to fix it, but still thought this information
> would be useful.

The problem is known, the test infrastructure is catching this among
other existing problems. You can also file a bug to bugzilla if this
doesn't exist already so we can track this.