Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread Tim Draegen
> On Aug 7, 2017, at 1:21 AM, Bron Gondwana wrote: > > A more cheap and nasty fix, assuming it's too late/complex to change the > protocol more, would be to keep AS, but change the validation to only require > checking the most recent AS, since validating the rest is meaningless. Bron, thanks

Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread Bron Gondwana
On Tue, 8 Aug 2017, at 00:50, Tim Draegen wrote: >> On Aug 7, 2017, at 1:21 AM, Bron Gondwana >> wrote:>> >> A more cheap and nasty fix, assuming it's too late/complex to change >> the protocol more, would be to keep AS, but change the validation to >> only require checking the most recent AS, si

Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread Seth Blank
On Sun, Aug 6, 2017 at 10:21 PM, Bron Gondwana wrote: > > *AS adds nothing over just having AMS signing its own AAR, and then you > only have to verify ONE signature, the most recent.* > > > > You either trust the most recent signer and trust that THEY validated the > previous signer/SPF (and so

Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread John Levine
In article <1502083287.2191248.1065195288.7cdc7...@webmail.messagingengine.com> you write: >I thought long and hard about using a less inflammatory title, but I >figure maybe going in hard is the right way here, because I'd rather >fix this before it becomes a standard! (and thanks Dave for your >

Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread Bron Gondwana
On Tue, 8 Aug 2017, at 00:50, Tim Draegen wrote: >> On Aug 7, 2017, at 1:21 AM, Bron Gondwana >> wrote:>> >> A more cheap and nasty fix, assuming it's too late/complex to change >> the protocol more, would be to keep AS, but change the validation to >> only require checking the most recent AS, si

Re: [dmarc-ietf] ARC-Seal is meaningless security theatre

2017-08-07 Thread Bron Gondwana
On Tue, 8 Aug 2017, at 09:22, Seth Blank wrote: > On Sun, Aug 6, 2017 at 10:21 PM, Bron Gondwana > wrote:>> *AS adds nothing over just having AMS > signing its own AAR, and then >> you only have to verify ONE signature, the most recent.*>> >> >> >> You either trust the most recent signer and t