5 ms·

This does seem like it might be prone to pranksters copying a particular doorbell code and putting it outside someone else's house (or several houses), distribu

by dghf 2y ago

This does seem like it might be prone to pranksters copying a particular doorbell code and putting it outside someone else's house (or several houses), distributing fake flyers that include it ("Scan here for a chance to win a cruise!"), and so forth.

nkozyra 2y ago
My immediate thought was: get an esp32 with an eink display and regenerate the code every ten minutes, but of course we've left the extremely easy realm quickly. But I agree I wouldn't want a static QR code linked to anything that could bother me.
- atoav 2y ago
  Then, why not hook up a button to said ESP32 and improve the UX by multiple magnitudes? Oh.
  - cinntaile 2y ago
    I know I know. The QR link can resolve to a captcha/puzzle that needs to be solved before it actually rings!
    - nkozyra 2y ago
      Also we'll serve ads on it.
      - kfarr 2y ago
        Choose the quarter pounder in all of the photos…
        dirkc 2y ago
        It will use a LLM to interview you and decide if you are allowed to ring the doorbell
        ibaikov 2y ago
        But LLMs cost money so it'll need a monthly subscription with tiers (for visitors too!)
        kfarr 2y ago
        Please insert 25 cents to continue this call
        kotaKat 2y ago
        Wait, hold on. Let's make the doorbell an NFC payment touchpoint. Tap and pay 25 cents to ring the doorbell. The more you tap (and pay), the more the doorbell will make an effort to reach the person on the other side. Wanna pay $20 to the doorbell? Sure, I guess it can ring my phone to let me know someone shows up...
        dylan604 2y ago
        Choose the quarter pounder with e.coli in all of the photos would be beneficial to the vendor as well
- EGreg 2y ago
  I build apps for a living, that solve real-world problems. Static QR codes make no sense by themselves because they can be replayed. Same goes for "pay with your face" biometrics. The person is supposed to confirm something on THEIR OWN phone, to authenticate themselves and their location. Then the QR code to scan can indeed be static. Since the person's phone has to have the Internet anyway to make requests, simply change the interface on the PHONE. QR codes printed on a flyer or wherever are meant to "start the conversation". The authentication can happen right after. But keep in mind that, by themselves, they are not enough. For example, if you're trying to do a ticketing system or attendance where people scan a QR code, they can just forward it to their friend. Better to have them PRESENT a QR code to be scanned. Having said that, WiFi access points and captive portals are better. Because once you authenticate, the next time is seamless. They can be used to take attendance in classrooms, and much more, seamlessly. (Except if it a person's phone is off. So then they have to come up and manually register, or you have to find that out by having a challenge during class that actually requires phones.) ATTENDANCE ONLINE: While I'm at it, I will mention one more thing. Authentication and "presence" can also include face recognition and eye tracking. There are lots of models for Tensorflow's JS port, such as "blazeface", that can do it in real-time. You can present a computer interface on your own wall and the person is authenticated with their face. But remember, once again, that this should only be used for your own software within your own organization, which you presumably trust. Because it can be replayed and spoofed by whoever has access to the back-end. Anyway, for remote learning, this becomes really useful because (e.g. during the pandemic) the teacher can have an on/off signal which M of N students are paying attention, and which are drifting off or walked away from the computer -- all WITHOUT seeing their video feeds. So it enhances privacy. We've built a simple tool where students can open a background tab for instance, which watches where their attention is, while they use whatever sites. The tool is deployed by the teachers. If you want to prevent tech-savvy students from spoofing this attendance, you have to ship some of the code, signed with your own HMAC or private key, every time, and do it in a third-party iframe so their JS code can't simply override it. They would have to rewrite the code in the time that the secret key for the HMAC changes (every 10 minutes). For that, they'd need to install their own user-agent, and very few students are going to go that far. But yes, if people do have their own user-agent, then they can pretty much do any kind of replay attack for attendance. Something to keep in mind. The only way I have found, to do attendance reliably online, in the presence of adversaries capable of wielding their own user-agents and rewriting code on the fly, is to have them join a videoconference and show a signed QR code on their phone while also completing challenges with their face. The private key might have to come from an agency that saw them arrive in person. The only way to defeat this is to corrupt the agency, making it give out a lot of private keys, and then deploy deepfake video avatars at scale (the kind DARPA wants to do) to complete all challenges. At that point, they AI is probably good enough that you prefer the bots to humans anyway LOL. SYBIL ATTACKS I will also say a word about sybil attacks. The best ways I have found to prevent them are imposing a cost (but those who can recoup the cost will still do it) or grandfathered accounts. The problem with grandfathered accounts is that people can deploy software to automate existing accounts, and do it occassionally enough to avoid detection. The only way to prevent cheating in tests, for example, is to flip the classroom and have the students take the test in class. They can do it on their phones, as long as their phones notify the teacher when they put the app in the background. (However, there are still problems with phones that allow multiple apps side by side and don't tell the apps.) In case you are wondering, we are building some of this stuff on https://teaching.app https://teaching.app
- saaaaaam 2y ago
  How to massively over engineer a simple doorbell! I don’t mean this in a mean way and realise that your comment was mention the spirit of the conversation :)
  - tanseydavid 2y ago
    https://en.wikipedia.org/wiki/Rube_Goldberg_machine https://en.wikipedia.org/wiki/Rube_Goldberg_machine
- barryrandall 2y ago
  You could also just use a cheap pet-compatible motion sensor and sound the chime when there’s motion on the porch.
  - axelthegerman 2y ago
    That sounds like a lot more setup than simply slapping a QR code somewhere doesn't it?
middayc 2y ago
there is probably very little cost in changing the QR code, almost like changing a password in an odd case that anything like this happens.
- sam29681749 2y ago
  Wouldn't you also need to reprint the barcode? Get it's probably unlikely to happen, but there seems to be a lot more friction than changing a password.
  - nkozyra 2y ago
    You could rotate them at random so you're only printing a dozen or so. But again, still more hassle than helpful and if you forget to switch it the problem remains.
c22 2y ago
Swapping codes on two adjacent houses would be pretty amusing.
quesera 2y ago
Easily pranked yes, but not that different from other cases which turn out to be non-problems in daily life. People could also print flyers with your phone number on them. Add your email address to spam lists. Etc etc.
maaaaattttt 2y ago
I think this could be solved by asking the last name of the person/family you want to ring the bell for, once the QR code URL is loaded. This doesn't solve the issue of: what if multiple appartements want to use this solution as a doorbell? Then you'd have to add the name on the QR code and it's back to square one.
- NicuCalcea 2y ago
  I'll be honest, if I have to scan a QR code and fill in a form to let someone know I'm at their door, I'm turning around and going home.
  - ozim 2y ago
    Not even trying to knock on the door?
dirkc 2y ago
Pranking is a legitimate concern. What do you reckon the worst case scenario to be and what do you reckon are reasonable pranks?
- dghf 2y ago
  Worst case? I guess that would be so many bogus notifications that your doorbell is rendered effectively useless. But in that case, I suppose you're moving out of the realm of pranks into what is essentially a DoS attack.
0x457 2y ago
Generate a new code when it happens? It's not like you have to keep the same QR code for some comptibility reason.
deleted 2y ago
[deleted]

by dghf 2y ago

nkozyra 2y ago

My immediate thought was: get an esp32 with an eink display and regenerate the code every ten minutes, but of course we've left the extremely easy realm quickly. But I agree I wouldn't want a static QR code linked to anything that could bother me.

atoav 2y ago
Then, why not hook up a button to said ESP32 and improve the UX by multiple magnitudes? Oh.
- cinntaile 2y ago
  I know I know. The QR link can resolve to a captcha/puzzle that needs to be solved before it actually rings!
  - nkozyra 2y ago
    Also we'll serve ads on it.
    - kfarr 2y ago
      Choose the quarter pounder in all of the photos…
      - dirkc 2y ago
        It will use a LLM to interview you and decide if you are allowed to ring the doorbell
        ibaikov 2y ago
        But LLMs cost money so it'll need a monthly subscription with tiers (for visitors too!)
        kfarr 2y ago
        Please insert 25 cents to continue this call
        kotaKat 2y ago
        Wait, hold on. Let's make the doorbell an NFC payment touchpoint. Tap and pay 25 cents to ring the doorbell. The more you tap (and pay), the more the doorbell will make an effort to reach the person on the other side. Wanna pay $20 to the doorbell? Sure, I guess it can ring my phone to let me know someone shows up...
      - dylan604 2y ago
        Choose the quarter pounder with e.coli in all of the photos would be beneficial to the vendor as well
EGreg 2y ago
I build apps for a living, that solve real-world problems. Static QR codes make no sense by themselves because they can be replayed. Same goes for "pay with your face" biometrics. The person is supposed to confirm something on THEIR OWN phone, to authenticate themselves and their location. Then the QR code to scan can indeed be static. Since the person's phone has to have the Internet anyway to make requests, simply change the interface on the PHONE. QR codes printed on a flyer or wherever are meant to "start the conversation". The authentication can happen right after. But keep in mind that, by themselves, they are not enough. For example, if you're trying to do a ticketing system or attendance where people scan a QR code, they can just forward it to their friend. Better to have them PRESENT a QR code to be scanned. Having said that, WiFi access points and captive portals are better. Because once you authenticate, the next time is seamless. They can be used to take attendance in classrooms, and much more, seamlessly. (Except if it a person's phone is off. So then they have to come up and manually register, or you have to find that out by having a challenge during class that actually requires phones.) ATTENDANCE ONLINE: While I'm at it, I will mention one more thing. Authentication and "presence" can also include face recognition and eye tracking. There are lots of models for Tensorflow's JS port, such as "blazeface", that can do it in real-time. You can present a computer interface on your own wall and the person is authenticated with their face. But remember, once again, that this should only be used for your own software within your own organization, which you presumably trust. Because it can be replayed and spoofed by whoever has access to the back-end. Anyway, for remote learning, this becomes really useful because (e.g. during the pandemic) the teacher can have an on/off signal which M of N students are paying attention, and which are drifting off or walked away from the computer -- all WITHOUT seeing their video feeds. So it enhances privacy. We've built a simple tool where students can open a background tab for instance, which watches where their attention is, while they use whatever sites. The tool is deployed by the teachers. If you want to prevent tech-savvy students from spoofing this attendance, you have to ship some of the code, signed with your own HMAC or private key, every time, and do it in a third-party iframe so their JS code can't simply override it. They would have to rewrite the code in the time that the secret key for the HMAC changes (every 10 minutes). For that, they'd need to install their own user-agent, and very few students are going to go that far. But yes, if people do have their own user-agent, then they can pretty much do any kind of replay attack for attendance. Something to keep in mind. The only way I have found, to do attendance reliably online, in the presence of adversaries capable of wielding their own user-agents and rewriting code on the fly, is to have them join a videoconference and show a signed QR code on their phone while also completing challenges with their face. The private key might have to come from an agency that saw them arrive in person. The only way to defeat this is to corrupt the agency, making it give out a lot of private keys, and then deploy deepfake video avatars at scale (the kind DARPA wants to do) to complete all challenges. At that point, they AI is probably good enough that you prefer the bots to humans anyway LOL. SYBIL ATTACKS I will also say a word about sybil attacks. The best ways I have found to prevent them are imposing a cost (but those who can recoup the cost will still do it) or grandfathered accounts. The problem with grandfathered accounts is that people can deploy software to automate existing accounts, and do it occassionally enough to avoid detection. The only way to prevent cheating in tests, for example, is to flip the classroom and have the students take the test in class. They can do it on their phones, as long as their phones notify the teacher when they put the app in the background. (However, there are still problems with phones that allow multiple apps side by side and don't tell the apps.) In case you are wondering, we are building some of this stuff on https://teaching.app https://teaching.app
saaaaaam 2y ago
How to massively over engineer a simple doorbell! I don’t mean this in a mean way and realise that your comment was mention the spirit of the conversation :)
- tanseydavid 2y ago
  https://en.wikipedia.org/wiki/Rube_Goldberg_machine https://en.wikipedia.org/wiki/Rube_Goldberg_machine
barryrandall 2y ago
You could also just use a cheap pet-compatible motion sensor and sound the chime when there’s motion on the porch.
- axelthegerman 2y ago
  That sounds like a lot more setup than simply slapping a QR code somewhere doesn't it?

middayc 2y ago

there is probably very little cost in changing the QR code, almost like changing a password in an odd case that anything like this happens.

sam29681749 2y ago
Wouldn't you also need to reprint the barcode? Get it's probably unlikely to happen, but there seems to be a lot more friction than changing a password.
- nkozyra 2y ago
  You could rotate them at random so you're only printing a dozen or so. But again, still more hassle than helpful and if you forget to switch it the problem remains.

c22 2y ago

Swapping codes on two adjacent houses would be pretty amusing.

quesera 2y ago

Easily pranked yes, but not that different from other cases which turn out to be non-problems in daily life. People could also print flyers with your phone number on them. Add your email address to spam lists. Etc etc.

maaaaattttt 2y ago

I think this could be solved by asking the last name of the person/family you want to ring the bell for, once the QR code URL is loaded. This doesn't solve the issue of: what if multiple appartements want to use this solution as a doorbell? Then you'd have to add the name on the QR code and it's back to square one.

NicuCalcea 2y ago
I'll be honest, if I have to scan a QR code and fill in a form to let someone know I'm at their door, I'm turning around and going home.
- ozim 2y ago
  Not even trying to knock on the door?

dirkc 2y ago

Pranking is a legitimate concern. What do you reckon the worst case scenario to be and what do you reckon are reasonable pranks?

dghf 2y ago
Worst case? I guess that would be so many bogus notifications that your doorbell is rendered effectively useless. But in that case, I suppose you're moving out of the realm of pranks into what is essentially a DoS attack.

0x457 2y ago

Generate a new code when it happens? It's not like you have to keep the same QR code for some comptibility reason.

deleted 2y ago

[deleted]