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I'm writing a communication product that uses encryption to store the communications. A couple of things spring to mind when reading this: 1. It's trivially ea

I'm writing a communication product that uses encryption to store the communications. A couple of things spring to mind when reading this: 1. It's trivially easy to write a communication service that end-to-end encrypts using modern libraries (in my case, Go). The encryption part took about a day to build, without me needing to understand any of the maths I was using. I haven't had any penetration tests on it, yet, but I understand that Go's encryption libraries are all tested and the implementation (plumbing them together) is pretty simple and hard to get wrong. So even if FB gives the security services some way of reading messages, then the bad people can have their own tool within a few days. 1b. There are other services, not as popular, that provide solid end-to-end encryption already (hello Keybase), that the bad people can use immediately. This is not about stopping the bad people from encrypting their messages, this is about getting access to what everyone else is saying. 2. It's already practically infeasible for a communications company to implement end-to-end encryption without breaking existing laws (mostly about copyright). Facebook's "end-to-end encryption" on message content will have to include a copyright content filter in order to not be targeted by the copyright legal industry, and the incoming EU legislation on implementing content filters on any service that can share content. All this points at this not being about terrorists and protecting children, but at it being about mass surveillance of civilian populations. It's notable that of the "five eyes" participants, it's only the US, UK and Australia who have contributed to the open letter. These three countries are the most keen on mass domestic surveillance (in the West anyway).

thunderrabbit 7y ago
> This is not about stopping the bad people from encrypting their messages, this is about getting access to what everyone else is saying. Thank you.
SheinhardtWigCo 7y ago
“Trivially easy” causes me to raise an eyebrow. Hubris and cryptography don’t mix well. Which libraries are you using?
- johannes1234321 7y ago
  Given any set of modern libraries encrypting the transporr end-to-end is trivial. Still hard are verfication processes, for distributing certs/public keys and some secure memory handling if you want to protect the unencrypted message on the local machine in some way.
  - marcus_holmes 7y ago
    yeah, making sure the secret keys stay secret is harder than plumbing the encryption calls together
- roblabla 7y ago
  It isn't hubris. I've written a toy E2E encrypted messaging as well. I haven't had to write a single line of actual crypto - libraries like libsodium ensure I just have to tell it the kind of security I want, and it handles all the dirty work for me. The hard part then shifts to the logic: 1. Ensuring the protocol doesn't allow accidentally leaking the data to an adversary somehow. 2. Ensuring the data is secured on the endpoints (the phone) - making sure the keys are secure and can't leak, and making sure the data is only decrypted when needed and for the time period it's needed. Not that this is easy to get right either. But with crypto being an essentially "solved" problem, we get to spend more time ensuring those bits work properly.
  - oconnor663 7y ago
    Wouldn't you say the hard part is getting someone else's key reliably?
    - tialaramex 7y ago
      Yes, identity verification is certainly the hard part of setup for any secure communications system. But in modern systems the cute thing is that this only really matters at the moment it happens. It's a big problem if there is an active adversary attacking you when you try to communicate, but a moment later it doesn't matter at all. Many governments are reluctant to just attack their own citizens 24/7. It's a bit too blatant. So they're obliged to try to attack most communications retrospectively. Suppose I am an intelligence analyst and I just figured out that murderous terrorist Jenny Smith sent instructions for planting a bomb to another member of her cell on Saturday at 11:42:05 precisely using let's say Signal. I have a copy of the IP packets sending the instructions. I have essentially unlimited resources to dedicate to the task. And Jenny didn't even have a reliable way to assure herself she was sending the instructions to the right person. Surely I can do something? Right? Nope. I'm screwed. Since I wasn't actively attacking Jenny back when it happened, she got the right keys, and I can no more decrypt these IP packets now than I could travel back in time and stop her sending them.
3pt14159 7y ago
Before someone becomes a terrorist they are recruited and cultivated. It might be trivial for existing contacts to install Signal, it's not trivial for people to recruit when they put up extra barriers to communication. I don't know if this is going to matter in the long run, since one way or another the NSA is going to get in, but in the short run it will damage our ability to track how extremism is spreading.
- pc86 7y ago
  > since one way or another the NSA is going to get in This is not even remotely a foregone conclusion. > but in the short run it will damage our ability to track how extremism is spreading If the only way the intelligence community can "track how extremism is spreading" is by violating the privacy of everyone on the planet, then so be it. Liberty trumps security.
  - GordonS 7y ago
    You seem to have read the GP's comment very differently than me. I took it to mean that using encrypted apps could potentially reduce the spread of extremism, by simple virtue of the fact that it's a barrier to entry?
    - pc86 7y ago
      Yes I think we did. I reread it and I think the "it" that will damage our ability to track extremism is E2EE. Based on that interpretation I took that the GP was against E2EE for this reason and felt that allowing the government access to these communications was ok if it was for the right reasons. I could definitely be wrong, though!
NeedMoreTea 7y ago
There are encrypted chat apps such as Signal that the bad people -- the Conservative party -- are now using for internal communications. Presumably including Priti Patel.
- z9e 7y ago
  Can we please not go into divisive politics here?
  - NeedMoreTea 7y ago
    It's a reasonably well reported statement of fact, brought in IIRC at the suggestion of Dominic Cummings. Why should discussions by party members and researchers be less susceptible to all the ills claimed for Facebook? Why should different rules apply? Are they immune from illegality? So it speaks to the hypocrisy of those calling for the change. It would be no different if it were another party calling for same, whilst at the same time switching from Whatsapp to Signal. It would be reasonable for police investigating such possible crimes to have more secure channels. Edit: Someone else -- johnnycab -- already posted links further down to some of the reports: https://news.ycombinator.com/item?id=21863326 https://news.ycombinator.com/item?id=21863326
    - tialaramex 7y ago
      Back when the UK government decided that it should be possible to order records of TCP/IP connections to be kept for similar reasons the MPs asked if there shouldn't be an exception for them. Surely, they argued, as upstanding people they shouldn't be subject to the same rules as ordinary citizens. The Home Secretary of that time told them that unfortunately that was technically impossible, they'd just have to trust that it wouldn't be abused (for example to spy on opposition politicians)... Lots of people comforted themselves that that law required the Home Secretary to send a letter to order any such collection, and they imagined her writing maybe a dozen letters on a busy day, something like "Dear Tiny ISP, please keep records for your subscriber Steve Smith who we suspect of being a pervert". People more familiar with the actual negotiations behind the scenes say the letters actually went "Dear large UK Internet Backbone provider, per this new law, please store absolutely everything until further notice"...
apeace 7y ago
I think this raises the question: will governments eventually ask the Go authors to remove these tools from the language/ecosystem?
dehrmann 7y ago
> The encryption part took about a day to build, without me needing to understand any of the maths I was using You don't need to understand how ciphers work per se, but you do need to understand how to put the building blocks together and think about attacks, e.g. do you ever have the key in memory on your servers. I love this picture; the data's encrypted, but with a bad mode of operation: https://upload.wikimedia.org/wikipedia/commons/f/f0/Tux_ecb.jpg https://upload.wikimedia.org/wikipedia/commons/f/f0/Tux_ecb....
freepor 7y ago
There is an infinite number of encrypted chat apps that can be built. What is finite is the number of organizations that have a brand strong enough to launch one that becomes popular immediately. What’s also finite is the number of organizations that can get that funding to build popularity slowly (eg Signal). The governments may successfully be able to stomp out those services and just leave the tiny thousand-user apps alone. As soon as one of those becomes popular enough, rinse and repeat the above.
metta2uall 7y ago
Well, by forcing the "bad people" into less popular apps they become much easier to identify through other metadata as the popular apps account for the vast majority of the "everyday person" traffic.. I think to get a balanced perspective we should appreciate the dilemma & work done by the govt security people. Their job is to fight the terrorists, pedophiles, forced sex traffickers, and many other "very bad people" - which is easier said than done. In the future WMDs will become cheaper, easier to produce and more powerful, so the issue is becoming more acute. They understandably want better tools to increase their chances of success & reduce likely traumatic failures. They seem to be doing ok with terrorists in the West at the moment, but failing badly with the other categories. The risk of abuses against everyday civilians are there and I don't have the solutions. But I would presume that the majority of people will trade off a significant reduction to their privacy for a slight increase in physical safety, so that will likely happen. Vastly improving the governance & oversight of the security agencies is one way forward. Otherwise when the next disaster strikes, the security agencies will rapidly make a successful grab for more power.

thunderrabbit 7y ago

> This is not about stopping the bad people from encrypting their messages, this is about getting access to what everyone else is saying. Thank you.

SheinhardtWigCo 7y ago

“Trivially easy” causes me to raise an eyebrow. Hubris and cryptography don’t mix well. Which libraries are you using?

johannes1234321 7y ago
Given any set of modern libraries encrypting the transporr end-to-end is trivial. Still hard are verfication processes, for distributing certs/public keys and some secure memory handling if you want to protect the unencrypted message on the local machine in some way.
- marcus_holmes 7y ago
  yeah, making sure the secret keys stay secret is harder than plumbing the encryption calls together
roblabla 7y ago
It isn't hubris. I've written a toy E2E encrypted messaging as well. I haven't had to write a single line of actual crypto - libraries like libsodium ensure I just have to tell it the kind of security I want, and it handles all the dirty work for me. The hard part then shifts to the logic: 1. Ensuring the protocol doesn't allow accidentally leaking the data to an adversary somehow. 2. Ensuring the data is secured on the endpoints (the phone) - making sure the keys are secure and can't leak, and making sure the data is only decrypted when needed and for the time period it's needed. Not that this is easy to get right either. But with crypto being an essentially "solved" problem, we get to spend more time ensuring those bits work properly.
- oconnor663 7y ago
  Wouldn't you say the hard part is getting someone else's key reliably?
  - tialaramex 7y ago
    Yes, identity verification is certainly the hard part of setup for any secure communications system. But in modern systems the cute thing is that this only really matters at the moment it happens. It's a big problem if there is an active adversary attacking you when you try to communicate, but a moment later it doesn't matter at all. Many governments are reluctant to just attack their own citizens 24/7. It's a bit too blatant. So they're obliged to try to attack most communications retrospectively. Suppose I am an intelligence analyst and I just figured out that murderous terrorist Jenny Smith sent instructions for planting a bomb to another member of her cell on Saturday at 11:42:05 precisely using let's say Signal. I have a copy of the IP packets sending the instructions. I have essentially unlimited resources to dedicate to the task. And Jenny didn't even have a reliable way to assure herself she was sending the instructions to the right person. Surely I can do something? Right? Nope. I'm screwed. Since I wasn't actively attacking Jenny back when it happened, she got the right keys, and I can no more decrypt these IP packets now than I could travel back in time and stop her sending them.

3pt14159 7y ago

Before someone becomes a terrorist they are recruited and cultivated. It might be trivial for existing contacts to install Signal, it's not trivial for people to recruit when they put up extra barriers to communication. I don't know if this is going to matter in the long run, since one way or another the NSA is going to get in, but in the short run it will damage our ability to track how extremism is spreading.

pc86 7y ago
> since one way or another the NSA is going to get in This is not even remotely a foregone conclusion. > but in the short run it will damage our ability to track how extremism is spreading If the only way the intelligence community can "track how extremism is spreading" is by violating the privacy of everyone on the planet, then so be it. Liberty trumps security.
- GordonS 7y ago
  You seem to have read the GP's comment very differently than me. I took it to mean that using encrypted apps could potentially reduce the spread of extremism, by simple virtue of the fact that it's a barrier to entry?
  - pc86 7y ago
    Yes I think we did. I reread it and I think the "it" that will damage our ability to track extremism is E2EE. Based on that interpretation I took that the GP was against E2EE for this reason and felt that allowing the government access to these communications was ok if it was for the right reasons. I could definitely be wrong, though!

NeedMoreTea 7y ago

There are encrypted chat apps such as Signal that the bad people -- the Conservative party -- are now using for internal communications. Presumably including Priti Patel.

z9e 7y ago
Can we please not go into divisive politics here?
- NeedMoreTea 7y ago
  It's a reasonably well reported statement of fact, brought in IIRC at the suggestion of Dominic Cummings. Why should discussions by party members and researchers be less susceptible to all the ills claimed for Facebook? Why should different rules apply? Are they immune from illegality? So it speaks to the hypocrisy of those calling for the change. It would be no different if it were another party calling for same, whilst at the same time switching from Whatsapp to Signal. It would be reasonable for police investigating such possible crimes to have more secure channels. Edit: Someone else -- johnnycab -- already posted links further down to some of the reports: https://news.ycombinator.com/item?id=21863326 https://news.ycombinator.com/item?id=21863326
  - tialaramex 7y ago
    Back when the UK government decided that it should be possible to order records of TCP/IP connections to be kept for similar reasons the MPs asked if there shouldn't be an exception for them. Surely, they argued, as upstanding people they shouldn't be subject to the same rules as ordinary citizens. The Home Secretary of that time told them that unfortunately that was technically impossible, they'd just have to trust that it wouldn't be abused (for example to spy on opposition politicians)... Lots of people comforted themselves that that law required the Home Secretary to send a letter to order any such collection, and they imagined her writing maybe a dozen letters on a busy day, something like "Dear Tiny ISP, please keep records for your subscriber Steve Smith who we suspect of being a pervert". People more familiar with the actual negotiations behind the scenes say the letters actually went "Dear large UK Internet Backbone provider, per this new law, please store absolutely everything until further notice"...

apeace 7y ago

I think this raises the question: will governments eventually ask the Go authors to remove these tools from the language/ecosystem?

dehrmann 7y ago

> The encryption part took about a day to build, without me needing to understand any of the maths I was using You don't need to understand how ciphers work per se, but you do need to understand how to put the building blocks together and think about attacks, e.g. do you ever have the key in memory on your servers. I love this picture; the data's encrypted, but with a bad mode of operation: https://upload.wikimedia.org/wikipedia/commons/f/f0/Tux_ecb.jpg https://upload.wikimedia.org/wikipedia/commons/f/f0/Tux_ecb....

freepor 7y ago

There is an infinite number of encrypted chat apps that can be built. What is finite is the number of organizations that have a brand strong enough to launch one that becomes popular immediately. What’s also finite is the number of organizations that can get that funding to build popularity slowly (eg Signal). The governments may successfully be able to stomp out those services and just leave the tiny thousand-user apps alone. As soon as one of those becomes popular enough, rinse and repeat the above.

metta2uall 7y ago

Well, by forcing the "bad people" into less popular apps they become much easier to identify through other metadata as the popular apps account for the vast majority of the "everyday person" traffic.. I think to get a balanced perspective we should appreciate the dilemma & work done by the govt security people. Their job is to fight the terrorists, pedophiles, forced sex traffickers, and many other "very bad people" - which is easier said than done. In the future WMDs will become cheaper, easier to produce and more powerful, so the issue is becoming more acute. They understandably want better tools to increase their chances of success & reduce likely traumatic failures. They seem to be doing ok with terrorists in the West at the moment, but failing badly with the other categories. The risk of abuses against everyday civilians are there and I don't have the solutions. But I would presume that the majority of people will trade off a significant reduction to their privacy for a slight increase in physical safety, so that will likely happen. Vastly improving the governance & oversight of the security agencies is one way forward. Otherwise when the next disaster strikes, the security agencies will rapidly make a successful grab for more power.