Re: [ietf-smtp] DSNs
Sam Varshavchik <mrsam@courier-mta.com> Sun, 26 April 2020 23:56 UTC
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From: Sam Varshavchik <mrsam@courier-mta.com>
To: ietf-smtp@ietf.org
Date: Sun, 26 Apr 2020 19:56:13 -0400
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Subject: Re: [ietf-smtp] DSNs
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John Levine writes: > In article <cone.1587934924.981704.31890.1004@monster.email-scan.com> you > write: > >Incoming mail is addressed to a valid mailbox. Your MTA accepts it. As such, > >the sender already knows it is a valid recipient. > > > >I don't follow what information is getting leaked, if a second later a > >success DSN gets sent to the sender. The sender already knows it's a valid > >mailbox, by the virtue of the fact that the mail was accepted. > > Not necessarily. It might be forwarded, it might bounce later. It's already known that if you are going to forward your mailbox, you want to get your bounces go somewhere else. The bouncing on forwarded mail are mostly useless to the original sender. The original sender can't do anything about them. In this situation I would considering forwarding to be a secondary act that has no bearing on the original mail. The message was delivered to the recipient. The fact that it was forwarded by the recipient's mailbox is a out of scope for DSNs. > We can bikeshed forever about whether you send a success DSN if it's > delivered to a spam folder. If it's succesfully delivered to a spam folder, that seems like a smashing success to me. But that's not important. I thought there were some security implications to successful DSNs, that I didn't know about; but looks like that's not the case; all are things that have been known for decades…
- [ietf-smtp] SMTP, DSNs, and enhanced replies (was… John C Klensin
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Hector Santos
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Brandon Long
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … John Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Dave Crocker
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies John R Levine
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies … Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Ned Freed
- Re: [ietf-smtp] SMTP, DSNs, and enhanced replies Jeremy Harris
- Re: [ietf-smtp] DSNs Claus Assmann
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Jeremy Harris
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John C Klensin
- [ietf-smtp] Variable HELO name, was DSNs Alessandro Vesely
- Re: [ietf-smtp] DSNs Arnt Gulbrandsen
- Re: [ietf-smtp] Variable HELO name, was DSNs Ned Freed
- Re: [ietf-smtp] Variable HELO name, was DSNs John C Klensin
- Re: [ietf-smtp] DSNs John C Klensin
- Re: [ietf-smtp] DSNs Dave Crocker
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Scott Kitterman
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Valdis Kl ē tnieks
- Re: [ietf-smtp] DSNs Laura Atkins
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs John Levine
- Re: [ietf-smtp] DSNs Sam Varshavchik
- Re: [ietf-smtp] DSNs Ned Freed
- Re: [ietf-smtp] DSNs Viktor Dukhovni
- Re: [ietf-smtp] DSNs Sam Varshavchik