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Michael Thomas wrote:
My point is that for what I consider good reasons, Mailman will add the msg_footer to such a message by wrapping additional MIME structure around the original multipart/alternative message.
I.e., the original
multipart/alternative text/plain text/html
message will be recast as
multipart/mixed multipart/alternative text/plain text/html text/plain
with the final text/plain part containing the footer. Given that the original content-type header is included in the signature, the signature is now broken.
If we were to take a different approach with a signature containing l=, either the l= includes all the text/plain and at least part of the text/html, in which we can't add the footer to the text/plain alternative without breaking the signature, or the l= includes none of the text/html part in which case the signature is not very good at verifying the validity of the text/html part. This further assumes we even know how to add a footer to a text/html part.
See <http://www.python.org/cgi-bin/faqw-mm.py?req=show&file=faq04.039.htp> for some discussion of why we do it the way we do.
-- Mark Sapiro <msapiro@value.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan
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Mark Sapiro wrote:
Ah yes, multipart/alternative vs. lists is definitely unhappy for DKIM, though simpler mime layouts make it through on average -- at least given our sample. I agree that if you have to add a footer at all, that the way your doing it in this case seems perfectly reasonable.
Are you still speaking of multipart/alernative? Right now what we do for, say, text/html is not sign the trailing </body></html> and final --. This allows lists to insert their trailers as they normally do in the mime/html body. Similar for text/plain too. For us at least (and it may be that we're just have a lot of html hating geeks), this seems to do the trick pretty well. I see some breakage from multipart/ alternative, but not _that_ much.
Mike
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Michael Thomas wrote:
Yes, I am.
This assumes that something appended to an html body will render in a nice way. Maybe it will in most cases, but there's no guarantee.
I'm not sure how typical your Mailman environment is. For regular, non-geek lists, I think that most posts from Y! will be multipart/alternative, and I think that will be a problem if the MLM touches the message body in almost any way.
-- Mark Sapiro <msapiro@value.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan
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Mark Sapiro wrote:
Ah yes, multipart/alternative vs. lists is definitely unhappy for DKIM, though simpler mime layouts make it through on average -- at least given our sample. I agree that if you have to add a footer at all, that the way your doing it in this case seems perfectly reasonable.
Are you still speaking of multipart/alernative? Right now what we do for, say, text/html is not sign the trailing </body></html> and final --. This allows lists to insert their trailers as they normally do in the mime/html body. Similar for text/plain too. For us at least (and it may be that we're just have a lot of html hating geeks), this seems to do the trick pretty well. I see some breakage from multipart/ alternative, but not _that_ much.
Mike
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Michael Thomas wrote:
Yes, I am.
This assumes that something appended to an html body will render in a nice way. Maybe it will in most cases, but there's no guarantee.
I'm not sure how typical your Mailman environment is. For regular, non-geek lists, I think that most posts from Y! will be multipart/alternative, and I think that will be a problem if the MLM touches the message body in almost any way.
-- Mark Sapiro <msapiro@value.net> The highway is for gamblers, San Francisco Bay Area, California better use your sense - B. Dylan
participants (2)
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Mark Sapiro
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Michael Thomas