... or because a police insider is threatened and/or hit repeatedly with a $5 wrench. One of the most effective decryption tools.
Police can store keys inside HSMs. Tech firms can give training and develop software stacks to ensure secure workflows if they want to.
You can also use a targeted approach. Allow the police to request intercepts of specific phone numbers. Tech firm rotates the public key being served to the clients, replacing it with a police key. They add a special flag that says "don't put any sign this happened in the UI". Now police can intercept just that specific phone number.
There's lots of ways to do this at different points in the security/usability spectrum, it's all just an engineering problem.
Also, bear in mind that police and governments won't find this argument convincing because they can already access every other form of electronic communication and in reality mass leaks of private data have never been an issue.
This is just wildly untrue. The 2015 OPM hack (in which an APT stole security clearance records) was a mass spill of private data. The Shadow Brokers leak put the NSA's most sensitive tools on the public internet for anyone to download. And of course we might never hear about collected intelligence that had been purloined by an adversary in the course of an offensive cyber operation.
And I know about the Shadow Brokers. Not personal information.
"Tools and methods" are in fact considered more sensitive than any personal information in the IC. The system you're proposing presumes the existence of at least one unhackable organization, and I regret to inform you that there is no such thing.
Firstly, nothing I've proposed demands unhackable organizations. That appears to be a requirement you invented. No security system presumes that! The so-called E2E encryption systems are hackable via several different organizations today: you could hack Meta client teams and insert code into the next releases, you could hack Google/Apple and tamper with the code as it gets shipped via the store, you could hack a phone OEM and insert a backdoor into the devices themselves.
Secondly, if you think government agencies would get hacked more often than tech firms then you may be right, but that's also irrelevant to any points being made here. The goal here isn't to design a perfect system, it's just to point out that the claim that no system can exist at all isn't true. Responding to that with "but your comment doesn't contain a full design doc for a system I personally judge as perfect" isn't going to get us far. Governments don't care if the system is perfect, right? They're OK with some leaks from hacked police departments.
Thirdly, I haven't even been making concrete proposals! Just pointing out how cryptography works as examples. If I was hired to implement these requirements tomorrow I wouldn't do things directly in those ways, they're oversimplified, hence the references to textbooks.
Sure, iCloud backups and photos are technically readable (they're not under e2ee) but policies and procedures exist to allow law enforcement to access them as well.
What you're asking for is that e2ee be eliminated in favor of a process-heavy solution. But at the end of the day, any human-dependent process can be broken by social engineering and a lack of vigilance.
Yes, an e2ee session can be broken by shipping a hacked client update to an endpoint. But that's much harder to accomplish, human- and process-wise, than obtaining the right key from the right person.
Key leaks are also relatively easy to prevent because secret keys are not relevant to investigations, so they never have to leave the interception framework and handed to a human operator. Sure, the infrastructure could be compromised, but that's already an extremely severe issue if you just have metadata in it.
France, 1940, religious census data.
It's not at all, which is why your solution ideas miss the mark completely.
It is fundamentally a "humans can be corrupted" problem.
Everything you describe is a backdoor of various forms. Backdoors have nothing that prevent abuse other than triple pinky promise to only spy the bad guys (by whoever gets to define who is the bad guy, which changes over time).
Whenever you have a system where people have access to bypass it, you'll soon enough have some of those people be corrupted to abuse it, or ordered by higher ups to abuse it or threatened by various way to abuse. Since people are involved, there is a 100% chance this will happen.
As long as corruptible humans are in the loop (i.e. as long as humanity exists) the one and only way to avoid corrupted abuse of backdoors is to not have any backdoors.
Tech firms also know that programmers can make mistakes whilst implementing complex cryptography, or even be corrupted, yet this is not itself an argument against implementing cryptography!
To repeat once again, we're not debating the ethics of E2E encryption here. Please don't waste time trying to convince me that E2E is encryption is a good idea, because (if it was real and worked) I'd agree with you! But your argument is a Type 1 No by the scheme presented in the article. It is a "we'd really rather not" social argument.
The problem our industry has is typified by the article. Too many tech people argue that giving police access to WhatsApp encryption is actually a Type 3 "it can't be done for fundamental physical reasons so it doesn't matter who demands it" problem, but that isn't true. Remember that governments don't care about E2E encryption whatsoever in any way. They would much rather ban it as a source of unnecessary problems. If tech firms claim they can't turn it off completely, they're obviously lying and that will just enrage governments. If tech firms claim they can't keep it whilst providing targeted access, governments don't care about that either. After all, email isn't end-to-end encrypted, nor is SMS, nor are normal phone calls, nor are letters. Why should WhatsApp be any different?
In reality it actually is possible to design a system that stops people with only server-side access to WhatsApp reading messages, whilst still breaking if the clients are compromised, and which allows police to have targeted levels of access without any risk of universal master key leaks. There are lots of ways to do that. You can use secure enclaves, zero knowledge proofs, or more exotic algorithms. But it's also not really relevant to the point I'm making, which is about the No Type being presented to governments. There was surely a better example that could have been chosen for a Type 3 No.
This is changing the goalposts.
Giving police access to whatsapp chat is trivially easy. But that's not the question.
The pro-surveillance people say "Give the good-guy police (whoever they are) access to everything and keep it secure from the Bad Guys Whom We Oppose (whoever they might be this week)". That one is indeed impossible due to the laws of information theory.
> without any risk of universal master key leaks
You're looking at a technical problem when this is not that, it is a humanity problem.
It's relatively easy to avoid e.g. master key leaks. That's an irrelevant implementation detail. What matters is that if some set of people have unfettered access to bypass all protections, then all the Bad Guys will also have that access soon enough because you can't keep people from getting corrupted/threatened. No matter how hard you wish, you can't. Humans are like that.
So, is this impossible due to human nature or the "laws of information theory"? Which is it? And if the latter what "law" are you thinking of, exactly? Can you name these laws?
Here's the problem: it's neither impossible mathematically nor practically. Remember the kerfuffle over the NSA's backdoored ECDRBG algorithm? That was a very pure textbook example of what's possible, it would have allowed the NSA and only the NSA to decrypt TLS streams using it. According to you that would have been physically impossible due to violating some sort of law, but it's not. Cryptographers know how to construct such systems, there are many ways.
But the existence of such solutions doesn't even matter. Lawful intercept abilities have existed for ages, governments will happily accept a solution of just turning off E2E encryption entirely, and the possibility that governments or tech firms will get hacked doesn't bother them because that's a transient problem that can be made hard by throwing money at it.
They also don't care about corruption because the countries demanding this have low levels of it. Governments are the original experts in corruption, you might say, and have evolved a lot of different mechanisms to fight it. Finally, remember that all these systems are already hackable or corruptible. Pay off someone who works on the WhatsApp mobile app team and unless Meta's internal controls detect it, it's game over.
Yes. It's simple, if you send information in a recoverable way to another entity, they can recover it. If that entity involves humans, they can and will with 100% certainty be corrupted or threatened to obtain the information improperly.
> Remember the kerfuffle over the NSA's backdoored ECDRBG algorithm?
Amusing that your example is a counterexample to your thesis. Exactly. Backdoors never serve only their would-be masters. That's the impossible part.
If this is not blindingly obvious by now, I fail at being able to explain it better.
So it's not a counter-example and your amusement is misplaced.
My old boss and I were recently laid off because my company (Livingston International) has been doing massive layoffs, because the company has been losing clients and money over repeated phishing attacks. We always shat on the assumed tech-illiterate person or persons responsible for us now having to sign in multiple times per DAY with MFA. Right before we left he mentioned this suspicious email he got the other day… and he clicked on it. It was one of those internal “we got you! Be careful next time!” emails. Come on man.
https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst6...
It says it's from 2015, but the Catalyst 6500 product line is much, much older. And quite a few companies sold both mediation devices and encryption software.
All these problems exist with access to metadata, so police and service providers already need to address them today. I'm not saying that this isn't challenging (maybe it is, I don't work in this field), it's just that handling content (especially text message) within the existing framework wouldn't be such a massive change because of the existing infrastructure and procedures.
In countries with higher corruption levels than the US data/metadata from “lawful” access is sold on a black market. I don’t think the problem of keeping data safe solved in a future proof way even in the first world countries and if encryption will be compromised sooner or later data or even keys will be sold/stolen/abused.
By not sending a copy to the police, you can guarantee that those things won't happen.