netdev - Re: IPsec replay sequence number overflow behavior? (RFC4303 section 3.3.3)

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]

Date:	Sun, 9 Dec 2007 09:37:56 -0500
From:	Paul Moore <paul.moore@...com>
To:	Herbert Xu <herbert@...dor.apana.org.au>
Cc:	netdev@...r.kernel.org, latten@...ibm.com
Subject: Re: IPsec replay sequence number overflow behavior? (RFC4303 section 3.3.3)

On Saturday 08 December 2007 9:13:48 pm Herbert Xu wrote:
> Paul Moore <paul.moore@...com> wrote:
> > If it is a bug, I think the basic fix should be pretty simple, changing
> > the above xfrm_output() code to the following:
> >
> >   if (x->type->flags & XFRM_TYPE_REPLAY_PROT) {
> >           XFRM_SKB_CB(skb)->seq = ++x->replay.oseq;
> > +          if (x->replay.oseq == 0)
> > +                  goto error;
>
> Yes we need this check.
>
> However please add an unlikely around it since it's a 1-in-4
> billion event :)

 :)

Thanks for clearing that up, I'll send a patch this week; complete with an 
unlikely (similar to the RFC quality IPsec audit patch I sent on Friday) and 
a decrement to the sequence counter in case of rollover.

-- 
paul moore
linux security @ hp
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html