Re: [PATCH libnetfilter_queue 0/3] pktbuff API updates

[Duncan Roe <duncan_roe@optusnet.com.au>]

Hi Pablo,

On Tue, May 05, 2020 at 02:30:34PM +0200, Pablo Neira Ayuso wrote:
> Hi Duncan,
>
> On Thu, Apr 30, 2020 at 04:34:04PM +1000, Duncan Roe wrote:
> [..]
> > Oh well in that case, how about:
> >
> > >	struct pkt_buff *pktb_alloc2(int family, void *buf, size_t buf_size, void *data, size_t len, size_t extra);
>
> Getting better. But why do you still need 'extra'?

As per other emails, no. I think it's fine not to zeroise that memory.
>
> > I.e. exactly as you suggested in
> > https://www.spinics.net/lists/netfilter-devel/msg65830.html except s/head/buf/
> >
> > And we tell users to dimension buf to NFQ_BUFFER_SIZE. We don't even need to
> > expose pktb_head_size().
>
> NFQ_BUFFER_SIZE tells what is the maximum netlink message size coming
> from the kernel. That netlink message contains metadata and the actual
> payload data.

As per other emails, I'll define and document NFQ_BUFFER_SIZE. If you have a
suggestion for a smaller value, I can put that in a v2.
>
> The pktbuff structure helps you deal with the payload data, not the
> netlink message itself.

Pablo, can we agree to proceed with

> struct pkt_buff *pktb_alloc2(int family, void *buf, size_t buf_size, void *data, size_t len);

then I can get on with the rest of the release.

Cheers ... Duncan.