[ietf-dkim] Possible problem with "simple" body canonicalization -- trailing CRLFs

[Michael Thomas]

Tony Hansen wrote:

>This not a problem when using DATA. Check 2821 section 4.1.1.4; the
>ending crlf.crlf was clarified as being the trailing crlf of the last
>line of the message followed by the terminator sequence.
>
>   Note that the first <CRLF> of this terminating sequence is also the
>   <CRLF> that ends the final line of the data (message text) or, if
>   there was no data, ends the DATA command itself.
>
>You are correct that the problem exists when using BDAT.
>
>My implementation uses the last CRLF in if it's there. If there is no
>last CRLF, it does *not* add one.
>
>  
>
Having just worked through this myself, I'll say that Tony's interpretation
*has* to be the correct one otherwise an l= less than the body length won't
be correct. Namely:

"a b</body></html>" where l=3 is: "a b" not "a b<crlf>" or any other
weird interpretation. This is definitely worth a mention in the draft.

       Mike