netdev - Re: [RFC PATCH v2 net-next 0/3] flow_offload: Re-add per-action statistics

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <7cdc59fd-e90f-6ff2-f429-257c8844be26@solarflare.com>
Date:   Mon, 20 May 2019 16:37:10 +0100
From:   Edward Cree <ecree@...arflare.com>
To:     Pablo Neira Ayuso <pablo@...filter.org>
CC:     Jamal Hadi Salim <jhs@...atatu.com>, Jiri Pirko <jiri@...nulli.us>,
        "David Miller" <davem@...emloft.net>,
        netdev <netdev@...r.kernel.org>,
        Cong Wang <xiyou.wangcong@...il.com>,
        Andy Gospodarek <andy@...yhouse.net>,
        "Jakub Kicinski" <jakub.kicinski@...ronome.com>,
        Michael Chan <michael.chan@...adcom.com>,
        Vishal Kulkarni <vishal@...lsio.com>
Subject: Re: [RFC PATCH v2 net-next 0/3] flow_offload: Re-add per-action
 statistics

On 19/05/2019 01:22, Pablo Neira Ayuso wrote:
> On Fri, May 17, 2019 at 04:27:29PM +0100, Edward Cree wrote:
>> On 15/05/2019 20:39, Edward Cree wrote:
> [...]
>> Pablo, how do the two options interact with your netfilter offload?  I'm
>>  guessing it's easier for you to find a unique pointer than to generate
>>  a unique u32 action_index for each action.  I'm also assuming that
>>  netfilter doesn't have a notion of shared actions.
> It has that shared actions concept, see:
>
> https://netfilter.org/projects/nfacct/
>
> Have a look at 'nfacct' in iptables-extensions(8) manpage.
Thanks.  Looking at net/netfilter/nfnetlink_acct.c, it looks as though you
 don't have a u32 index in there; for the cookie approach, would the
 address of the struct nf_acct (casted to unsigned long) work to uniquely
 identify actions that should be shared?
I'm not 100% sure how nf (or nfacct) offload is going to look, so I might
 be barking up the wrong tree here.  But it seems like the cookie method
 should work better for you — even if you did have an index, how would you
 avoid collisions with TC actions using the same indices if both are in
 use on a box?  Cookies OTOH are pointers, so guaranteed unique :)

-Ed