Phil Sutter <phil@xxxxxx> wrote:
> Unify nat, masquerade and redirect statements, they widely share their
> syntax.
> This seemingly valid change breaks the parser with this rule:
>
> | snat ip prefix to ip saddr map { 10.141.11.0/24 : 192.168.2.0/24 }
Yes.
> Problem is that 'prefix' is not in SC_IP and close_scope_ip called from
> parser_bison.y:5067 is not sufficient. I assumed explicit scope closing
> would eliminate this lookahead problem. Did I find a proof against the
> concept or is there a bug in my patch?
You have to keep 'prefix' in the global scope.
What should work as well is to permit 'prefix' from SCANSTATE_IP(6).
The problem is that the parser can't close the new 'IP' scope until
it has enough tokens available to match a complete bison rule.
So, it is in IP scope, sees 'prefix' (which will be STRING as the
PREFIX scan rule is off) and that ends up in a parser error due to lack
of a 'IP STRING' rule.
