newspostuser --> To, but what about Reply-To?

[Kevin P. Fleming]

Ken Murchison wrote:

> +archive.info-cyrus at utdallas.edu wrote:
> 
>> On Tue, 17 Feb 2004, Ken Murchison wrote:
>>
>>
>>> I've actually been looking for more info on this type of thing, and here
>>> is what I found:
>>>
>>> http://www.unicom.com/pw/reply-to-harmful.html
>>> http://cr.yp.to/proto/replyto.html
>>>
>>> I can strip the address before transferring the article via NNTP, but
>>> this doesn't help if the article is posted/replied via SMTP.

I can see what you're dealing with here, and it's significant. You've 
got a message in a folder with its Reply-To: set to 
post+folder.subfolder, and the original To:/CC: headers still in place.

If the user does a straight reply, the reply goes via SMTP to the 
post+folder.subfolder address, which is now in the To: header. When it 
arrives at the lmtp2nntp gateway, this must be stripped from the To: 
header, and the Reply-To: header inserted again.

If the user does a "reply all", then the above scenario occurs, but also 
other copies of the message are delivered to the original recipients of 
the source message. This could include a variety of problematic things 
including other newsgroup names (the original message was crossposted), 
some or all of which are not present on this Cyrus installation or even 
SMTP recipients (normal mail addresses). The reply may very well be sent 
to these other SMTP recipients as well, without any Cyrus software being 
involved at all, in which case the post+folder.subfolder address would 
be exposed to them. This will have to be handled by the outbound MTA, 
there is no way around that, and it's a complicated documentation issue 
to boot.

How ever the user does a reply, the reply will end up back in the folder 
via lmtp2nntp, and is available to be sent upstream to an NNTP server. 
When this happens, I think all the headers in the message need to be 
searched for _any_ post+XXX addresses and those should be stripped; the 
message may have been sent to more than one local newsgroup folder. It 
would be ideal if the NNTP upload could see that and send only one copy 
to the relevant NNTP server (so the message would preserve its 
crossposting), but that's not easy to do I'm sure.
---
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