[ietf-dkim] detecting header mutations after signing

[Dave CROCKER]

On 10/18/2010 3:31 AM, Ian Eiloart wrote:
> --On 15 October 2010 11:53:51 -0400 Dave CROCKER<dhc at dcrocker.net>  wrote:
>> On 10/15/2010 11:40 AM, Mark Delany wrote:
>>> Well, if you want to introduce semantic changes why not just change
>>> the meaning of h=from:to: to be semantically identical to
>>> h=from:from:to:to:
>>
>> This would mean that it is /never/ ok to add a listed header field after
>> signing.  Adding would /always/ break the signature.
>
> I assumed that the proposal applied only to headers rfc5322 says cannot be
> duplicated.

That is a constraint that was not stated.  Specifications do not allow assuming. 
  As offered, the modification would have the effect that I stated and /not/ the 
one you state.


d/
-- 

   Dave Crocker
   Brandenburg InternetWorking
   bbiw.net