7 ms·

In most European countries you need to submit your ID to get any sort of working SIM card.

fossuser 6y ago
If that’s the case doesn’t it matter even less that signal requires it since it’s already known anyway? Signal’s use of phone numbers as IDs means they don’t have to have any of your contacts sent to their servers. As shown in the article they have no metadata and nothing to reveal beyond your phone number and when you signed up. These other apps send your social graph to their servers, track and store metadata, don’t have encryption on by default, roll their own cryptography, or some combination of all of these things. The phone number obsession on HN seems dumb to me - a meaningless thing for people to repeat and complain about that doesn’t actually matter so they can sound like they know what they’re talking about. I don’t get it. The only real criticism I have for signal is that they’re not federated so they’re vulnerable to shutdown. I think that’s okay though because we have Matrix working on that problem and having both is probably a good thing. It’s also a thoughtful and intentional choice: https://signal.org/blog/the-ecosystem-is-moving/ https://signal.org/blog/the-ecosystem-is-moving/ The response from Matrix: https://matrix.org/blog/2020/01/02/on-privacy-versus-freedom https://matrix.org/blog/2020/01/02/on-privacy-versus-freedom
- K2L8M11N2 6y ago
  I feel comfortable with giving my Telegram username out to random people on the internet and posting it on my website because it doesn’t mean anything outside of Telegram. I wouldn’t post my phone number publicly.
  - fossuser 6y ago
    That’s fair, thanks - I think for secure communication with people you don’t know personally or trust, it’d be better to use something that doesn’t share your phone number.
- est31 6y ago
  > roll their own cryptography Signal did the same thing. They invented their own cryptographic algorithms. https://en.wikipedia.org/wiki/Double_Ratchet_Algorithm https://en.wikipedia.org/wiki/Double_Ratchet_Algorithm And the social graph IS sent to servers by Signal. It's protected only by hashing (trivial to circumvent) and by the Intel SGX technology (a bit harder to circumvent, but I doubt that the US govt can't do it).
  - fossuser 6y ago
    My (limited) understanding is numbers are queried to see if accounts exist, but those queries are not connected to the users sending them (and they are obscured in transit). Am I wrong? Signal’s cryptography has also gotten a ton of attention, I don’t think the same is true for competitors.
    - est31 6y ago
      Transit encryption is employed by other services as well. Whether there is de-correlation on the cloud backend I don't know. Maybe there is, but you can't really verify that and it's easy to correlate them again, especially if clients use ipv6 or non-CGNAT ipv4.
  - the_why_of_y 6y ago
    Signal's crypto is an incremental improvement of existing algorithms with good reputation, OTR and SCIMP. Telegram's crypto is reportedly designed from scratch, with questionable choices such as SHA1 and MAC-then-encrypt. https://www.cryptofails.com/post/70546720222/telegrams-cryptanalysis-contest https://www.cryptofails.com/post/70546720222/telegrams-crypt... https://eprint.iacr.org/2015/1177.pdf https://eprint.iacr.org/2015/1177.pdf
    - est31 6y ago
      I didn't want to claim that Telegram's crypto was better or as good as Signal's. But saying that Telegram rolled their own crypto while Signal did not is misleading as both designed their own protocols. Also, Telegram uses SHA256 now in the places relevant for security, so that point was resolved.
- K2L8M11N2 6y ago
  Assuming you’re using Signal for organizing something the government doesn’t want you organizing, if one member of the group gets rubber-hosed into unlocking their phone, the govt instantly gets a list of verifiably correct names of people involved. In contrast, with a service that lets you use usernames that maneuver would reveal nothing but those usernames (which are as pseudonymous as it gets).
  - fossuser 6y ago
    Thanks - the concern makes sense to me given that context.
  - walrus01 6y ago
    One of the other problems with using phone numbers, is that it provides an opening for adversaries. Now they know your phone number, which can be used for social-engineering attacks to attempt to bypass 2FA for any other online services tied to your phone number. Either for 2FA or for account-recovery/i-forgot-my-password functionality. 2FA by SMS is wrong and broken and nobody should use it, but they do. Adversaries will attempt to social engineer customer service for your phone carrier into issuing them a new SIM or porting out the number, so they can receive verification SMS and phone calls.
    - goatsi 6y ago
      Signal uses a registration pin to prevent that exact attack.
      - vinay427 6y ago
        Maybe I misread, but the GP doesn't seem to be talking about impersonating a user on Signal, but rather impersonating that user on other websites that depend on SMS 2FA sent to their phone number that is now visible through Signal.
- glenstein 6y ago
  >If that’s the case doesn’t it matter even less that signal requires it since it’s already known anyway? Well, if you're operating on that premise, which is to say, a premise of complete and total resignation and surrender, then from that starting point of course you haven't lost anything. I don't think anybody is joining you though in agreeing that that's a legitimate starting place to analyze privacy concerns associated with the phone number requirement.
  - fossuser 6y ago
    This is such an uncharitable interpretation of what I was saying that it's basically a straw man. If you're required to use ID to get a SIM (as K2L8M11N2 stated in the parent comment I replied to), then what I was saying follows - that the person is already tied to the phone number anyway. In this context Signal revealing the only data they have (that a phone number signed up on X day) really doesn't matter or reveal anything new. K2L8M11N2's other response to my comment is a helpful clarification, it's less about what can be compelled from Signal the company and more about what can be turned over if a user's device is compromised. In that context the name to number connection is more serious because they also have the content.
    - glenstein 6y ago
      I'm sorry but absolutely nothing about this is a straw man or uncharitable, and I'll explain why. >If you're required to use ID to get a SIM (as K2L8M11N2 stated in the parent comment I replied to), then what I was saying follows Yes, and this is what I was responding to. You want that "if" to be taken for granted as an unchallenged starting premise to your entire argument. And that amounts to a massive privacy concession. And the fact that I'm challenging that premise, and bringing up the privacy concerns that are associated with that "if", that is the thing that you're describing as uncharitable. Even though you don't appear to dispute that it is indeed a privacy concession. And it only follows if you don't contemplate alternatives to using a phone number, which is what I took to be their point about the problems associated with a phone number. >and more about what can be turned over if a user's device is compromised. In that context the name to number connection is more serious because they also have the content. That's going true in any context where your number can be revealed, which is why it has unique disadvantages that usernames wouldn't have, under any conceivable hypothetical scenario. I'm glad that you benefited from their clarification but that struck me as a truism about the nature of phone numbers versus the nature of usernames.
- sdjkfgsdjkfghjh 6y ago
  Just do like TOR services. Hash some garbage with your private key. done. This is no excuse other than copying the leading app for no good reason.
- mekster 6y ago
  Signal can have a great interest in buying up private data linked with phone numbers and add people that they chat with with their phone numbers, sell again with the added data.
squarefoot 6y ago
That wouldn't be a problem in phones where the radio part is screened from the system (Pinephone?) so that implementing encryption can be effective. The SIM might be tied with my me, but any eavesdropper would see only noise because the outgoing data is encrypted by the system before entering the radio hardware and is decrypted by the system after leaving it. They can know I generated some traffic at a certain moment, which is the same information they could get from the carrier operator, but that's about it.
Nursie 6y ago
In the UK you can buy a SIM from a vending machine in the airport.

If that’s the case doesn’t it matter even less that signal requires it since it’s already known anyway? Signal’s use of phone numbers as IDs means they don’t have to have any of your contacts sent to their servers. As shown in the article they have no metadata and nothing to reveal beyond your phone number and when you signed up. These other apps send your social graph to their servers, track and store metadata, don’t have encryption on by default, roll their own cryptography, or some combination of all of these things. The phone number obsession on HN seems dumb to me - a meaningless thing for people to repeat and complain about that doesn’t actually matter so they can sound like they know what they’re talking about. I don’t get it. The only real criticism I have for signal is that they’re not federated so they’re vulnerable to shutdown. I think that’s okay though because we have Matrix working on that problem and having both is probably a good thing. It’s also a thoughtful and intentional choice: https://signal.org/blog/the-ecosystem-is-moving/ https://signal.org/blog/the-ecosystem-is-moving/ The response from Matrix: https://matrix.org/blog/2020/01/02/on-privacy-versus-freedom https://matrix.org/blog/2020/01/02/on-privacy-versus-freedom

K2L8M11N2 6y ago
I feel comfortable with giving my Telegram username out to random people on the internet and posting it on my website because it doesn’t mean anything outside of Telegram. I wouldn’t post my phone number publicly.
- fossuser 6y ago
  That’s fair, thanks - I think for secure communication with people you don’t know personally or trust, it’d be better to use something that doesn’t share your phone number.
est31 6y ago
> roll their own cryptography Signal did the same thing. They invented their own cryptographic algorithms. https://en.wikipedia.org/wiki/Double_Ratchet_Algorithm https://en.wikipedia.org/wiki/Double_Ratchet_Algorithm And the social graph IS sent to servers by Signal. It's protected only by hashing (trivial to circumvent) and by the Intel SGX technology (a bit harder to circumvent, but I doubt that the US govt can't do it).
- fossuser 6y ago
  My (limited) understanding is numbers are queried to see if accounts exist, but those queries are not connected to the users sending them (and they are obscured in transit). Am I wrong? Signal’s cryptography has also gotten a ton of attention, I don’t think the same is true for competitors.
  - est31 6y ago
    Transit encryption is employed by other services as well. Whether there is de-correlation on the cloud backend I don't know. Maybe there is, but you can't really verify that and it's easy to correlate them again, especially if clients use ipv6 or non-CGNAT ipv4.
- the_why_of_y 6y ago
  Signal's crypto is an incremental improvement of existing algorithms with good reputation, OTR and SCIMP. Telegram's crypto is reportedly designed from scratch, with questionable choices such as SHA1 and MAC-then-encrypt. https://www.cryptofails.com/post/70546720222/telegrams-cryptanalysis-contest https://www.cryptofails.com/post/70546720222/telegrams-crypt... https://eprint.iacr.org/2015/1177.pdf https://eprint.iacr.org/2015/1177.pdf
  - est31 6y ago
    I didn't want to claim that Telegram's crypto was better or as good as Signal's. But saying that Telegram rolled their own crypto while Signal did not is misleading as both designed their own protocols. Also, Telegram uses SHA256 now in the places relevant for security, so that point was resolved.
K2L8M11N2 6y ago
Assuming you’re using Signal for organizing something the government doesn’t want you organizing, if one member of the group gets rubber-hosed into unlocking their phone, the govt instantly gets a list of verifiably correct names of people involved. In contrast, with a service that lets you use usernames that maneuver would reveal nothing but those usernames (which are as pseudonymous as it gets).
- fossuser 6y ago
  Thanks - the concern makes sense to me given that context.
- walrus01 6y ago
  One of the other problems with using phone numbers, is that it provides an opening for adversaries. Now they know your phone number, which can be used for social-engineering attacks to attempt to bypass 2FA for any other online services tied to your phone number. Either for 2FA or for account-recovery/i-forgot-my-password functionality. 2FA by SMS is wrong and broken and nobody should use it, but they do. Adversaries will attempt to social engineer customer service for your phone carrier into issuing them a new SIM or porting out the number, so they can receive verification SMS and phone calls.
  - goatsi 6y ago
    Signal uses a registration pin to prevent that exact attack.
    - vinay427 6y ago
      Maybe I misread, but the GP doesn't seem to be talking about impersonating a user on Signal, but rather impersonating that user on other websites that depend on SMS 2FA sent to their phone number that is now visible through Signal.
glenstein 6y ago
>If that’s the case doesn’t it matter even less that signal requires it since it’s already known anyway? Well, if you're operating on that premise, which is to say, a premise of complete and total resignation and surrender, then from that starting point of course you haven't lost anything. I don't think anybody is joining you though in agreeing that that's a legitimate starting place to analyze privacy concerns associated with the phone number requirement.
- fossuser 6y ago
  This is such an uncharitable interpretation of what I was saying that it's basically a straw man. If you're required to use ID to get a SIM (as K2L8M11N2 stated in the parent comment I replied to), then what I was saying follows - that the person is already tied to the phone number anyway. In this context Signal revealing the only data they have (that a phone number signed up on X day) really doesn't matter or reveal anything new. K2L8M11N2's other response to my comment is a helpful clarification, it's less about what can be compelled from Signal the company and more about what can be turned over if a user's device is compromised. In that context the name to number connection is more serious because they also have the content.
  - glenstein 6y ago
    I'm sorry but absolutely nothing about this is a straw man or uncharitable, and I'll explain why. >If you're required to use ID to get a SIM (as K2L8M11N2 stated in the parent comment I replied to), then what I was saying follows Yes, and this is what I was responding to. You want that "if" to be taken for granted as an unchallenged starting premise to your entire argument. And that amounts to a massive privacy concession. And the fact that I'm challenging that premise, and bringing up the privacy concerns that are associated with that "if", that is the thing that you're describing as uncharitable. Even though you don't appear to dispute that it is indeed a privacy concession. And it only follows if you don't contemplate alternatives to using a phone number, which is what I took to be their point about the problems associated with a phone number. >and more about what can be turned over if a user's device is compromised. In that context the name to number connection is more serious because they also have the content. That's going true in any context where your number can be revealed, which is why it has unique disadvantages that usernames wouldn't have, under any conceivable hypothetical scenario. I'm glad that you benefited from their clarification but that struck me as a truism about the nature of phone numbers versus the nature of usernames.
sdjkfgsdjkfghjh 6y ago
Just do like TOR services. Hash some garbage with your private key. done. This is no excuse other than copying the leading app for no good reason.
mekster 6y ago
Signal can have a great interest in buying up private data linked with phone numbers and add people that they chat with with their phone numbers, sell again with the added data.

squarefoot 6y ago

That wouldn't be a problem in phones where the radio part is screened from the system (Pinephone?) so that implementing encryption can be effective. The SIM might be tied with my me, but any eavesdropper would see only noise because the outgoing data is encrypted by the system before entering the radio hardware and is decrypted by the system after leaving it. They can know I generated some traffic at a certain moment, which is the same information they could get from the carrier operator, but that's about it.

Nursie 6y ago

In the UK you can buy a SIM from a vending machine in the airport.