[ietf-dkim] chained signatures, was l= summary

[Charles Lindsey]

On Fri, 29 May 2009 22:22:11 +0100, John R. Levine <johnl at iecc.com> wrote:

> I would really like to remove l= from DKIM to make it clear that it is  
> not
> a good idea to even try to guess the history of a message based on
> signatures that don't verify and cover the whole messag.

Speak for yourself.

I see a message with a broken, but otherwise plausible, signature, and  
that seems on the face of it a genuine message that I might very well care  
about, then I might well start to play around to see if some small munge  
of the message might have caused the broken signature. I have often done  
this in the case of seemingly broken Usenet control messages.

Just because a feature is likely to be used only rarely, and then only by  
people who have a good understanding of the protocol, is no reason to  
remove that possibility entirely from those people. That is just called  
"dumbing down", and "dumbing down" is a dumb idea.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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   Web: http://www.cs.man.ac.uk/~chl
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