The PGP Problem • Hacker News Board

Re: The PGP Problem

#131

Post by galad87 » Wed, Jul 17, 2019, 7:48 AM UTC

floatingatoll wrote: post #102

olliej wrote: post #91

Earlier quoted context omitted.

iMessage doesn't have any kind of auto deleted messages - it's a feature that messages are persistent across all your devices.

Incorrect. Audio messages are deleted two minutes after playback by default.

That's a client side feature meant to save disk space.

Re: The PGP Problem

#132

Post by txcwpalpha » Wed, Jul 17, 2019, 7:51 AM UTC

jeroenhd wrote: post #82

Whent talking about alternatives, Signal and WhatsApp get mentioned because they're easy to use. They are. Signal is pretty secure. WhatsApp probably is as well but we can't be sure. That is, until it isn't anymore. WhatsApp already has a key extraction protocol built right in for its Web interface. Signal has a web (Electron) interface as well, and a shitty one at that, where the messages also get decrypted. For Wha…

>WhatsApp already has a key extraction protocol built right in for its Web interface.

I don't believe this is correct. WhatsApp (and Signal AFAIK) web works by decrypting the original message on your phone, re-encrypting it with a different key that is shared with your web interface (this is what is being shared via the QR code when connecting to WhatsApp Web), sending it to the web client, and having your web client use the second key to decrypt. This is why your phone must continue to be powered on/connected to the network for the web service to work. The original key is never "extracted", and AFAIK can't be extracted by normal means.

There are a few apps that attempt to exploit a few security vulnerabilities to recreate your key for you if you lose it and need to access backups, but that isn't the same as what you're describing.

Re: The PGP Problem

#133

Post by foolfoolz » Wed, Jul 17, 2019, 7:52 AM UTC

i work with a manufacturer that’s a multi billion dollar behemoth and they move at the slowest possible pace. every decision takes weeks, a hundred emails, 20 phone calls, and 10 pdfs. we needed to add encryption to data we exchanged. they said PGP and gave me a pgp key. i encrypted a test file and gave my key back. within 20 mins we had an answer and moved on. this easiest part of anything we have ever integrated with them

Re: The PGP Problem

#134

Post by tialaramex » Wed, Jul 17, 2019, 7:57 AM UTC

Avamander wrote: post #121

fouc wrote: post #120

Earlier quoted context omitted.

I'm a little confused as to why you mention Signal and WhatsApp but not Telegram?

Telegram invented it's own crypto, without an audit it's untrustworthy. There's only Signal and Keybase that has been audited, so Whatsapp should be excluded from the list of trustworthy IM apps as well.

Whatsapp uses the exact same technology as Signal. If you consider that Signal is fine based on an audit of what is clearly an older version (do audits come out every day with new Signal releases? No, so the code you're running wasn't covered by the audit) then Whatsapp is fine based on being the same protocols with different branding.

Re: The PGP Problem

#135

Post by giomasce » Wed, Jul 17, 2019, 7:58 AM UTC

As usual, all articles of this OpenPGP-is-bad kind keep failing acknowledging OpenPGP's most important feature: it has a way (clumsy as much as you wish, but existing) to attach identities to keys, and to verify them. I have a rather well connected OpenPGP key, and that means that anyone can verify the signed emails claiming to be from me are actually from me, even if we never met. Of course you can mention XKCD and people saying they will never check a signature, but that's their problem, not mine. If do not bother to check your keys, any encrypting/signing system is untrustworthy. If you have a lot of keys, each for any of your crypto applications, and no way to cryptographically tie them to an identity, you will eventually mess them up, especially if they have to be deployed on more than one machine.

I am perfectly fine with saying that GnuPG uses old algorithms, or that different applications should use different keys, algorithms or techniques. But, please, when designing such systems keep in mind that you want to check where your keys come from and which identity they are attached to. And TTBOMK only OpenPGP is currently able to do that. To me it would be great if all crypto applications done in the right way would have a way to tie their keys to the OpenPGP web of trust, in the same way Monkeysphere tried to do for SSL and SSH keys.

Re: The PGP Problem

#136

Post by privateSFacct » Wed, Jul 17, 2019, 7:59 AM UTC

nightfly wrote: post #95

floatingatoll wrote: post #84

Earlier quoted context omitted.

Forcing iMessage to open will immediately result in MITM iMessage proxies that users can use to store iMessages that are meant to auto-delete, so that they can violate the wishes of the other party. These do not exist today because Apple binds iMessage to your hardware and bans your entire device when anyone is found to be operating such a service, either for themselves or others. Do you want open source clients that…

You can violate the wishes of the other party by taking a screenshot or, in the extreme, a photo of the screen. You're only preventing the very lazy/unmotivated from retaining messages.

Actually apples approach results in a MUCH lower level of retention than other providers even if someone can screenshot all conversations

Re: The PGP Problem

#137

Post by afiori » Wed, Jul 17, 2019, 8:00 AM UTC

AmericanChopper wrote: post #98

jeroenhd wrote: post #82

Whent talking about alternatives, Signal and WhatsApp get mentioned because they're easy to use. They are. Signal is pretty secure. WhatsApp probably is as well but we can't be sure. That is, until it isn't anymore. WhatsApp already has a key extraction protocol built right in for its Web interface. Signal has a web (Electron) interface as well, and a shitty one at that, where the messages also get decrypted. For Wha…

I think the real problem is that nobody has ever created a decent PKI, and I doubt a sufficiently secure PKI is even possible. CAs require you to trust people that aren’t supposed to be party to the communication (trust both not to be hostile, and not to be insecure themselves). All other forms of PKI offer entirely impractical authentication mechanisms. With signal and the like, your options are 1) Verify keys by be…

with signal I believe you can have already trusted contacts vouch for new contacts

Re: The PGP Problem

#138

Post by lorenzhs » Wed, Jul 17, 2019, 8:03 AM UTC

toxik wrote: post #129

floatingatoll wrote: post #102

Earlier quoted context omitted.

Incorrect. Audio messages are deleted two minutes after playback by default.

Which is a receiver-side setting and can be set to one year. Your point is moot.

For me, the two choices in settings are "after two minutes" and "never", nothing in between. As you said, this is not a security setting, it's a storage space-saving setting.

Re: The PGP Problem

#139

Post by jeroenhd » Wed, Jul 17, 2019, 8:03 AM UTC

fouc wrote: post #120

jeroenhd wrote: post #82

Whent talking about alternatives, Signal and WhatsApp get mentioned because they're easy to use. They are. Signal is pretty secure. WhatsApp probably is as well but we can't be sure. That is, until it isn't anymore. WhatsApp already has a key extraction protocol built right in for its Web interface. Signal has a web (Electron) interface as well, and a shitty one at that, where the messages also get decrypted. For Wha…

I'm a little confused as to why you mention Signal and WhatsApp but not Telegram?

Telegrams crypto is based on their own, contested protocol and is disabled by default. Telling someone to use that for secure communications is difficult because you also need to remind people to turn on encrypted communications.

Furthermore, signal and WhatsApp do e2e in group chats where telegram doesn't.

Dont get me wrong, I use Telegram daily (it's desktop clients far outperform any of its competitors), but it's not as secure as WhatsApp or Signal.

I'd classify Telegram as "maybe secure" but I wouldn't recommend it to people depending on the security of their messenger application.

Re: The PGP Problem

#140

Post by jeroenhd » Wed, Jul 17, 2019, 8:06 AM UTC

txcwpalpha wrote: post #132

jeroenhd wrote: post #82

Whent talking about alternatives, Signal and WhatsApp get mentioned because they're easy to use. They are. Signal is pretty secure. WhatsApp probably is as well but we can't be sure. That is, until it isn't anymore. WhatsApp already has a key extraction protocol built right in for its Web interface. Signal has a web (Electron) interface as well, and a shitty one at that, where the messages also get decrypted. For Wha…

>WhatsApp already has a key extraction protocol built right in for its Web interface. I don't believe this is correct. WhatsApp (and Signal AFAIK) web works by decrypting the original message on your phone, re-encrypting it with a different key that is shared with your web interface (this is what is being shared via the QR code when connecting to WhatsApp Web), sending it to the web client, and having your web client…

Fair enough, I suppose it's more of a plaintext extraction protocol.

Still, it would take just one decision by Facebook to completely disable e2e or add an actual key extraction method to WhatsApp and there's nothing you can do about it. While WhatsApp is the most secure of all conventional chat apps, it's certainly not a replacement for PGP in most use cases.