On Wed, 20 Dec 2006 14:29:24 -0000, Michael Thomas <mike(_at_)mtcc(_dot_)com>
wrote:
There is a perfectly good reason: some things in the mail path strip
trailing CRLF from the
body. We've experienced it firsthand and it's not uncommon, and would
reduce the survival
rate if changed.
But nobody is proposing any such thing. What stripping are you talking
about? If it is stripping a CRLF from an otherwise non-empty last line,
then ALL the rules under discussion require you to put it back, so that
what you are being asked to hash always has a CRLF at the end of any last
line that actually has real text in it. But if there is no real text
anywhere, then you canonicalize into an empty file.
So you start with
------------------
Last-Header: foobarCRLF
CRLF
barbazCRLF
CRLF
------------------
and some stupid system en route strips it down to
Last-Header: foobarCRLF
CRLF
barbaz
so in that case you put back the CRLF, and what you hash is:
------------------
barbazCRLF
------------------
And that is also what you would have hashed if it arrived exactly as
originally sent, or even if a few more CRLF-only lines had been picked up
somewhere.
BUT, if you started with
------------------
Last-Header: foobarCRLF
CRLF
------------------
or with
------------------
Last-Header: foobarCRLF
------------------
Then certinaly nothing will be stripped en route (there is nothing to
strip), but some CRLF-only lines might get added, but nevertheless what
you hash is still the empty file
------------------
------------------
And, in all those cases, the wording I suggested gives exactly that.
--
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131
Web: http://www.cs.man.ac.uk/~chl
Email: chl(_at_)clerew(_dot_)man(_dot_)ac(_dot_)uk Snail: 5 Clerewood Ave, CHEADLE, SK8 3JU, U.K.
PGP: 2C15F1A9 Fingerprint: 73 6D C2 51 93 A0 01 E7 65 E8 64 7E 14 A4 AB A5
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