DKIM might have non-repudiation as unintended side effect, but I am totally fine with it!
Ok Google: please publish your DKIM secret keys
31–40 of 492 posts
Re: Ok Google: please publish your DKIM secret keys
#32Earlier quoted context omitted.
The threat is not limited to politicians. Anyone (including you and your family members) could be blackmailed or otherwise publicly embarrassed.
> The threat is not limited to politicians. Anyone (including you and your family members) could be blackmailed or otherwise publicly embarrassed. ... for what they actually did. You think the solution is allowing people to be blackmailed or otherwise publicly embarrassed for things they didn't do, while removing their ability to verify that they didn't do them?
No. Once DKIM keys are published, one can simply deny all emails published "from their account". We currently have a way for an attacker to prove an email's origin years after the fact.
Re: Ok Google: please publish your DKIM secret keys
#33Can't you just set up your mailserver so that it drops all the crypto headers (DKIM-Signature, ...) after verifying them and storing the result in Authentication-Results? Only your server's Authentication-Results header is really relevant to spam filtering, anyway. Unless you're debugging something those headers seem irrelevant anyway, and they bloat the messages very much. (often times they are 3-4x the size of actu…
> Can't you just set up your mailserver so that it drops all the crypto headers (DKIM-Signature, ...) after verifying them and storing the result in Authentication-Results?
Matthew Green's ask isn't about protecting users that are tech-savvy enough to just set up their own mailserver and configure it a special way.
It's about protecting the billions of users that aren't.
Re: Ok Google: please publish your DKIM secret keys
#34Interesting/educational read but I'm still not convinced that this unintended side effect is a bad thing - it seems like a desirable property to have authenticated emails. Matt argues this might lead to regular folks (as opposed to politicians) getting blackmailed, but: 1) it seems unlikely this cryptographic proof is needed (he acknowledges this criticism in the post), and 2) what seems more likely to me is that pol…
You might want to validate your emails more than a few months out. Regardless of if your emails are valid or not, blackmail is still a crime. Not being able to have your emails validated doesn't protect you from blackmail. The power of blackmail is often in the social cost of the accusation itself. The thing that protects you from blackmail is not getting involved in things you can be blackmailed for. This is like sa…
Sounds like the "If you've got nothing to hide, you've got nothing to fear" argument. Not very compelling.
Re: Ok Google: please publish your DKIM secret keys
#35Earlier quoted context omitted.
You might want to validate your emails more than a few months out. Regardless of if your emails are valid or not, blackmail is still a crime. Not being able to have your emails validated doesn't protect you from blackmail. The power of blackmail is often in the social cost of the accusation itself. The thing that protects you from blackmail is not getting involved in things you can be blackmailed for. This is like sa…
> The thing that protects you from blackmail is not getting involved in things you can be blackmailed for. This is incorrect, because the things that someone can be blackmailed for is not the same as the set of immoral or unethical acts. You can be blackmailed for being gay, or for having a serious medical condition that's undisclosed. Neither of those situations is a "well just don't do that" kind of thing. The defe…
Doesn't DKIM make it harder to blackmail or destroy someone with fake emails because they can show their lack of authenticity?
Shouldn't we privilege protecting people from lies vs protecting people from the truth?
Re: Ok Google: please publish your DKIM secret keys
#36So the author's central thesis essentially seems to boil down to that leaked emails were able to be cryptographically verified, because of DKIM and so we should prevent that so people can't use email to blackmail politicians? Ultimately I prefer the more information that we can get on politicians available. It seems to me that especially when an elected official has something they don't want others to know about that…
I am not a lawyer, but I do not believe that DKIM provides repudiation specific to an individual. DKIM provides evidence that email originated on an email provider. The users neither own nor control the server and user accounts get compromised all the time as well as fake accounts created all the time. Google battles this daily. DKIM might be one piece of information, used in combination with a client IP address and some method of proving who was at that client IP address at the time, but I do not believe that DKIM could stand on its own.
For example, I have servers that DKIM sign emails. If a person uses my servers to send a death threat, the FBI is going to want web access logs and smtp logs.
Re: Ok Google: please publish your DKIM secret keys
#37Can't you just set up your mailserver so that it drops all the crypto headers (DKIM-Signature, ...) after verifying them and storing the result in Authentication-Results? Only your server's Authentication-Results header is really relevant to spam filtering, anyway. Unless you're debugging something those headers seem irrelevant anyway, and they bloat the messages very much. (often times they are 3-4x the size of actu…
That only protects the people who send email to you. It does nothing to protect you.
Re: Ok Google: please publish your DKIM secret keys
#38Earlier quoted context omitted.
The threat is not limited to politicians. Anyone (including you and your family members) could be blackmailed or otherwise publicly embarrassed.
> The threat is not limited to politicians. Anyone (including you and your family members) could be blackmailed or otherwise publicly embarrassed. ... for what they actually did. You think the solution is allowing people to be blackmailed or otherwise publicly embarrassed for things they didn't do, while removing their ability to verify that they didn't do them?
You're assuming no one has compromised the old keys. If that has happened, a blackmailer can forge old emails with proof of things you didn't do.
Re: Ok Google: please publish your DKIM secret keys
#39It seems like this would also be useful for proving contracts/statements over email in business law. While it may not have been designed for this purpose (and there could still be claims that the sending account was hacked, unlike a personal GPG key which identifies the individual rather than the infrastructure), it seems to be a pretty good thing to have.
Re: Ok Google: please publish your DKIM secret keys
#40If you have nothing to hide, you have nothing to fear! Privacy schmivacy.