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

[Eric Allman]

In doing an end-to-end read on -base this morning I came up with a 
possible difficulty with simple body canonicalization.

The description says that simple reduces CRLF 0*CRLF at the end of a 
message to a single CRLF.  But what if the message has no trailing 
CRLF at all?

Remember that in the sequence CRLF . CRLF, both CRLFs are part of the 
terminator, not part of the message.  Thus, a message reading:

        thanks <CRLF>
        . <CRLF>

in fact has no trailing CRLF on the message.  (This could also happen 
with BDAT, but that's not widely implemented.)

An approach to this might be to say that simple reduces 0*CRLF to a 
single CRLF (which is quite possibly what the current implementations 
actually do).

eric