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Ok Google: please publish your DKIM secret keys

blog.cryptographyengineering.com

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Re: Ok Google: please publish your DKIM secret keys

#411

Post by beagle3 »

Quekid5 wrote: post #349
beagle3 wrote: post #338

Earlier quoted context omitted.

> The point is that DKIM can be abused to lend undue credibility to falsified data... not that it can credibly attest true data. So can deep fakes. What makes deep fakes explainable and DKIM unexplainable? If the journalists interests do not align about DKIM, how come they align about deepfakes? I'm not saying journalists have any integrity. I'm just wondering why specifically for DKIM a "throw the baby out with the…

EDIT: Apologies probably wrong name of the phallacy, so I removed that. Regardless, the fact that deep-fakes exist has absolutely no impact on whether DKIM has problems or not.

I think what you are referring to is “whataboutism”, but I don’t think it is a case of whataboutism.

I have pointed out that in a similar case (potentially fake evidence), same actors (journalists) seem to have completely different incentives than those you hold so self-evident and I ask for an explanation of the difference - why is it so self evident that journalists have an incentive to not understand DKIM and not inform about it, but the same is not true of another concurrent challenge to evidence authenticity.

To me it sounds like you’re saying “journalists eat cotton candy because they like sweets, but they don’t like chocolate because they care about their teeth”. They might have this preference among cotton candy and chocolate, but the explanation is inconsistent and likely wrong.

Re: Ok Google: please publish your DKIM secret keys

#412

Post by aaron695 »

Have most people here lost there mind? We are pro-fascism now?

What right does Google have to force this onto us. If I want it, I'll chose it.

The idea I consented because the information was there somewhere and I should have know the complexities is as BS as hidden terms and conditions.

What annoys me is if you're pro fascism and want to force tracking onto people, just say it. But stupidity about how this isn't totalitarian is unforgivable. I have a right not to be tracked.

Re: Ok Google: please publish your DKIM secret keys

#413

Post by GoblinSlayer »

baobabKoodaa wrote: post #298
GoblinSlayer wrote: post #281

Earlier quoted context omitted.

Receipts can be signed with gnupg, it actually provides non-repudiation guarantee you want, DKIM doesn't provide that, it's only for journalists.

> Receipts can be signed with... In the real world it doesn't matter which cryptographic protocols are theoretically available for use. What matters is which protocols everyone else is using. For example, in the case of receipts for purchases on the web, literally everyone is using email. You will not be able to get amazon to sign a receipt with gnupg. If you want to embark on a path of convincing the world to move a…

GnuPG works with email, was created to do so.

Re: Ok Google: please publish your DKIM secret keys

#414

Post by baobabKoodaa »

shinigami wrote: post #378
baobabKoodaa wrote: post #348

Earlier quoted context omitted.

Because, without DKIM, a dishonest party can repudiate the email. Just as a written contract is superior to an oral contract, a non repudiable written contract is superior to a repudiable written contract.

So maybe digitally sign the contracts instead of unwillingly sign every single email you send?

Please explain how I can make a webshop like amazon digitally sign a contract?

Re: Ok Google: please publish your DKIM secret keys

#415

Post by baobabKoodaa »

GoblinSlayer wrote: post #413
baobabKoodaa wrote: post #298

Earlier quoted context omitted.

> Receipts can be signed with... In the real world it doesn't matter which cryptographic protocols are theoretically available for use. What matters is which protocols everyone else is using. For example, in the case of receipts for purchases on the web, literally everyone is using email. You will not be able to get amazon to sign a receipt with gnupg. If you want to embark on a path of convincing the world to move a…

GnuPG works with email, was created to do so.

> GnuPG works with email, was created to do so.

Please explain how I can make amazon sign my purchase receipt with GnuPG?

Re: Ok Google: please publish your DKIM secret keys

#416

Post by dan-robertson »

zaphirplane wrote: post #364
dan-robertson wrote: post #332

Earlier quoted context omitted.

Why is this argument not equivalent to the much-derided “nothing to hide” or “ban encryption by law” arguments? The way to have transparency into politician’s communications is to require them by law to be made public, and to use law enforcement to make sure that this actually happens. It seems that relying on information going over email (as opposed to eg signal), and getting hacked (perhaps you want it all hacked,…

I understand the sentiment For local politics this would expose the haggling/threats/backdowns not good for image making very hard to make deals For international, how do you expect this to work when a politician is getting briefing Or guidances or heads up about dealing with an dictatorship or a unfriendly global power or an foreign company ? Perhaps have a classification system ? Then everything will be secret clas…

To be clear, I’m not particularly advocating for my parent comment’s view that these communications should be transparent. I’m advocating for any such transparency being fair and deliberate rather than due to hacks and a protocol quirk.

Re: Ok Google: please publish your DKIM secret keys

#417

Post by compsciphd »

DKIM's protection aren't as strong as people say they are (though fairly strong)

1) DKIM doesn't protect the To: header in any reasonable way (its not really designed to). i.e. it protects it in the sense that the original email had that as the To: header, but this is easy to forge as the To: header is not used by SMTP in delivery (think Bcc). i.e. its easy to write emails that are To: that are never attempted to be delivered to said address.

2) DKIM (even on gmail) doesn't quite protect the From: header as one would expect. Yes, gmail in general makes it difficult to spoof the email in the From header (it will replace it with your own if you try in the general case), but there's a huge but, if you gave gmail itself access to use that e-mail. i.e. I can be compsciphd@gmail.com but if billgates@gmail.com was convinced to allow me access to send emails as billgates@gmail.com (either via cooperation or a technical or sociological hack) then i can do that without having access to the account. and this permission is permanent. as far as I can tell, it irrevocable and to other gmail users there is no indication that other accounts have this permission for your email.

so what do we learn

1) can't 100% trust DKIM to believe who an email was sent to unless you actually retrieved it out of said user's email spool 2) can't 100% trust DKIM to believe who actually sent an email (even on gmail)

now, do I think DKIM gives anywhere close to 0% trust. No, I think its much closer to 100 than 0, but one has to understand the limitations and most people who discuss it, don't seem to understand them.

the threat is a hack playing a very long game. If one doesn't view that long game hack threat as serious, then its close enough to 100% (especially if gmail rotates their keys even without making the private part public), but if a long game hack threat is a serious thing, then it drops.

Re: Ok Google: please publish your DKIM secret keys

#418

Post by baobabKoodaa »

cakoose wrote: post #410
baobabKoodaa wrote: post #290

Earlier quoted context omitted.

> I think the entire point is that non-repudiation shouldn't just magically happen unless intended, so yes, this is by design, and anyone who wants to send a signed email should explicitly send a signed email. Let's not pretend that the world would move away from email if Google made this change. We both know that's not going to happen. Given that, can you explain why you think the world would be a better place when…

First, "innocent people can be framed" is not that simple. Without non-repudiation, you don't automatically get to frame someone for whatever. You need to provide the usual (non-DKIM) evidence of whatever you're claiming. And even with non-repudiation, you can still try and frame someone. Not having the DKIM signature might be suspicious in some circumstances, but it doesn't eliminate the possibility. Second, "innoce…

> I don't want my private communication to become public, or publicly verifiable. That doesn't mean I'm not "innocent". This is not a fringe concept: https://en.wikipedia.org/wiki/Nothing_to_hide_argument

Yes, I agree we should have secure private messengers. But that has nothing to do with this discussion. First off, email is not a secure private messenger. Second, email would not become "more secure" by removing the accidental, partial non-repudiation that DKIM provides. Third, this comment chain that you are replying in right now, is about whether there exists any legitimate need for a third party to authenticate emails with DKIM after the emails have been sent. tptacek claimed that no such legitimate need exists. I've been arguing against this with a specific counter-example.

Re: Ok Google: please publish your DKIM secret keys

#419

Post by throwawayffffas »

The author underestimates how ready people are to believe slander. Publishing of DKIM keys will only allow people to produce more convincing faked emails. If a bunch of faked emails about a political leader signed with DKIM keys were released securities experts are going to say these keys are leaked and anyone could fake those emails but by the time they do the damage will have already happened and no one would be listening to them. The solution is not to release DKIM keys, but to make sure mails are not leaked. Throwing away signatures a few days after the email is delivered would not be a bad plan either, given they have actually served their purpose at that point.

Re: Ok Google: please publish your DKIM secret keys

#420

Post by hamburglar »

baobabKoodaa wrote: post #290
hamburglar wrote: post #242

Earlier quoted context omitted.

I think the entire point is that non-repudiation shouldn't just magically happen unless intended, so yes, this is by design, and anyone who wants to send a signed email should explicitly send a signed email.

> I think the entire point is that non-repudiation shouldn't just magically happen unless intended, so yes, this is by design, and anyone who wants to send a signed email should explicitly send a signed email. Let's not pretend that the world would move away from email if Google made this change. We both know that's not going to happen. Given that, can you explain why you think the world would be a better place when…

Nobody's talking about the world moving away from google. We're talking about the world simply not having non-repudiation built into email. A sender of an email doesn't owe you non-repudiation as a feature. Sorry if you think otherwise. Senders can add non-repudiation as a feature if they want to, which satisfies your purchase receipt scenario.
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