[ietf-dkim] 1193 considered harmful

[Barry Leiba]

>> It does not break current implementations though. As Murray
>> and Arvel's implementations can attest. 
> 
> Again, I didn't say your "X=" broke anything. I said that it
> requires a change in the signer and verifier in order to detect
> which of the header or body broke the signature.

Well, but that's irrelevant.  Mike's (correct) point is that if the 
verifier doesn't care about the new information provided, the verifier 
doesn't have to change.  With the proposal on the table, all verifiers 
would have to migrate.

I agree, though, that since the verifiers have to migrate anyway (to 
SHA-256), I think this is a less-than-compelling reason not to do this.

The "slippery slope" reason is more compelling.

Barry

--
Barry Leiba, Pervasive Computing Technology  (leiba at watson.ibm.com)
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