Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Jesse Thompson
A DNS-based lookup, perhaps in the style of ATSP as this thread is describing, to query for not just domain-level authorization, but also potentially user-level authorization, I think is compelling because it can: * Give domain owners a mechanism to achieve least-privilege authorization of 3rd

Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Douglas Foster
I mean something different. By "user-to-domain" I mean a DNS function which asserts: - When the message is signed by IETF, and the From address is my account, the message is considered authenticated by this DNS entry. - If the message is signed by IETF but the From address is a

Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Hector Santos
> On Apr 21, 2023, at 2:14 PM, Douglas Foster > wrote: > > Can it provide a user-to-domain authentication solution? Unless I am not following you, DKIM inherently provides "user-to-domain" authentication by hash binding the 5322 From: and To: headers. > That is what mailing lists need

Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Douglas Foster
Can it provide a user-to-domain authentication solution? That is what mailing lists need and that is what mailbox provider clients need. These use cases are pretty fundamental to our objective of getting mail authenticated without causing damage Or has everyone already decided that

Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Hector Santos
Doug, You might want review Doug Otis’s TPA (Third Party Authorization). It has a higher scale method. https://datatracker.ietf.org/doc/draft-otis-dkim-tpa-ssp/ Abstract TPA-label is a DNS-based prefix mechanism for DKIM policy records as a means to authorize Third-Party domains. This

Re: [dmarc-ietf] Is From spoofing an interoperability issue or not?

2023-04-21 Thread Scott Kitterman
On April 21, 2023 3:57:54 PM UTC, Alessandro Vesely wrote: >On Fri 21/Apr/2023 05:41:03 +0200 Scott Kitterman wrote: >> On April 20, 2023 4:18:08 PM UTC, Dotzero wrote: >>> On Thu, Apr 20, 2023 at 11:38 AM John Levine wrote: It appears that Alessandro Vesely said: > IMHO at

Re: [dmarc-ietf] Is From spoofing an interoperability issue or not?

2023-04-21 Thread Alessandro Vesely
On Fri 21/Apr/2023 05:41:03 +0200 Scott Kitterman wrote: On April 20, 2023 4:18:08 PM UTC, Dotzero wrote: On Thu, Apr 20, 2023 at 11:38 AM John Levine wrote: It appears that Alessandro Vesely said: IMHO at least an appendix should say that if you can't do anything better you have to

Re: [dmarc-ietf] Delegated authentication for Gmail

2023-04-21 Thread Douglas Foster
Thinking on this some more, there are some tricky design risks: - If the user-to-domain delegation scheme exposes an email address to the world, that information may be used for unwanted purposes, particularly increased spam volumes. Hashing provides part of that solution. The ATSP