So I'm asking for a pointer to the "how mailing lists break
signatures" report, if it exists so I can learn a bit more.
This was argued at some length about a year ago, but I can't
dig up offhand exactly where. Here's some of the more popular
mutations:
- Add fixed list name tag and varying message serial number to Subject:
- Add, delete, or replace Reply-To: header
- Reformat From: line into a standard form, e.g., <a(_at_)b> foo -> a(_at_)b
(foo)
- Add a bunch of extra headers like List-ID: and Precedence:
(shouldn't affect signature unless one replaces an existing header)
- Add a footer to the end of the body
- Add a "fronter" to the beginning of the body
- Add, delete, or reorder MIME parts
- Unpack and re-pack MIME parts with different delimiters
- Add a footer to one or more MIME parts
- Edit a footer into an HTML part (Yahoo groups does this)
- Convert HTML to text or vice versa
- Recode between 7bit and 8bit, or quoted printable to/from base64
I quickly came to the conclusion that other than the shrinking
minority of lists that do nothing at all to headers or body, it's
completely hopeless to try to make a signature that will survive list
processing.
And I still have a lot of trouble thinking of plausible scenarios
where mail from a domain with SSP restrictions would legitimately be
sent through a list.
R's,
John
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