[Swan-dev] Finding connections with %any fails due to only searching hostpair

[Andrew Cagney]

On Wed, 17 Mar 2021 at 11:21, Paul Wouters <paul at nohats.ca> wrote:
>
> On Wed, 17 Mar 2021, Andrew Cagney wrote:
>
> > looking around the above there's DHR's comment:
> >
> >        /*
> >         * ??? the use of hp looks nonsensical.
> >         * Either the first non-empty host_pair should be used
> >         * (like the current code) and the following should
> >         * be broken into two loops: first find the non-empty
> >         * host_pair list, second look through the host_pair list.
> >         * OR
> >         * what's really meant is look at the host_pair for
> >         * each sra, something that matches the current
> >         * nested loop structure but not what it actually does.
> >         */
> >
> > and this lookup:
> >
> >                hp = find_host_pair(&sra->this.host_addr,
> >                                    &sra->that.host_addr);
> >
> > so I suspect having the code also:
> >
> >           find_host_pair(&sra->this.host_addr, &unset_address)
> >
> > would do what you want and much faster.
>
> I don't think so, because I don't think hostpair will consider all the
> %any connections as belonging to the same host pair.
>
> > However, along the lines of DHR's comment, is this just adding to the problem?
>
> It's concept is really for left/right on the same IP (which is also an
> issue, with multiple behind NAT). Which is why I think the concept of
> hostpair is not sustainable. This isn't the first time code needed to
> be changed to search all connections :/

I still don't follow.

>From the bug. Before any connection, A's host-pair contains the
oriented template:

  local=192.168.173.129 remote = %any : A(template)

after one connection it contain both an oriented template and an
oriented instance:

  A(template): local=192.168.173.129 remote = %any :
  A(instance): local=192.168.173.129 remote = 192.168.173.144

the above lookup is only for 192.168.173.129->192.168.173.144, if it
also looked for 192.168.173.129->unset_address, it would find the
template.  Which I'm guessing is what is needed.