Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Privacy Pass Authentication for Kagi Search

blog.kagi.com

Post reply on HN
Print view View original

81–90 of 359 posts

Re: Privacy Pass Authentication for Kagi Search

#81

Post by pavon »

mortar wrote: post #74
pavon wrote: post #63

This is very cool. I'm curious about why there is a limit on the number of tokens generated per month, when this is only currently offered to unlimited accounts. Since the tokens all expire at the end of the month, tokens can't be horded to use Kagi after a subscription ends. Perhaps it is instead a resource issue where token generation is expensive. In that case though, I would think limiting tokens/day would be mor…

The reason they give in their docs is to “prevent abuse” ( https://help.kagi.com/kagi/privacy/privacy-pass.html ). It feels like they picked a number no user should hit, while keeping it low enough to not pass Kagi out “free” to all their friends.

Ah, that makes sense. It would be harder to detect sharing with this system than with account sharing. My thoughts went in a completely different direction when I read "abuse" the first time.

Re: Privacy Pass Authentication for Kagi Search

#82

Post by mortar »

alexwebb2 wrote: post #70
mortar wrote: post #65

I’m not insinuating for even a second that Kagi actually do this, but as a general rule, isn’t any privacy claim dubious at the moment given that more and more governments appear to be able to compel companies to identify their users (especially those searching for illegal content) and further forcefully insist they not disclose it? It’s disheartening to think the great progress we’re making in this sector could be u…

I think the idea here is that it literally can't be traced to the user – at no point is there anything passed that would allow Kagi to make the association between the user and the query.

Thanks, yes completely agree! I guess the part I’m concerned with is the politically side whereby they could be potentially compelled to change the method slightly after the fact and be forced to slip something in somewhere in a quite technical process now making it possible.

I’d love to assume this will never happen, I’m just concerned that even if it did I’d never find out - Because unfortunately the more popular this service gets for bad actors, the more of a target it becomes for the government with identification of users.

I guess as a search engine, we could assume the government may leave them well alone and still just focus on content creators.

Re: Privacy Pass Authentication for Kagi Search

#83

Post by daft_pink »

godelski wrote: post #18

This seems cool, but I still think the pricing of kagi is rather steep. It is $5/mo for 300 searches a month, which is really going to get you under 10 a day... That's insufficient. Then $10/mo (or $108/yr) for unlimited. I'm curious if anyone knows, are companies like Google and Microsoft making more than $10/mo/user? We often talk about paying with our data, but it is always unclear how much that data is worth. Kag…

The reason why it's worth it is because its search works really well. I've tried DuckDuckGo, Bing and always subconsciously ended up back at Google. This is the only search service I've used that works better than Google search and I think it's a combination of them not putting ads on the search and the way they let you tweak the search to block poor quality sites. How much it costs them or how much google profits vs your payment is not really relevant to me. It's the best working search engine in my opinion.

Re: Privacy Pass Authentication for Kagi Search

#84

Post by echoangle »

voytec wrote: post #73
ransom_rs wrote: post #62

Earlier quoted context omitted.

You have to generate the tokens while signed in, but once you have the tokens, you can use them without your searches being associated with your account (cryptographically provable).

[deleted by author]

If the method works as described (which is a cryptography issue and can be verified?), there’s no way to track you.

Your claim is a bit like saying „it’s impossible to encrypt mail, the government wouldn’t allow it“. But PGP still exists.

Re: Privacy Pass Authentication for Kagi Search

#85

Post by autoexec »

redserk wrote: post #33
godelski wrote: post #18

This seems cool, but I still think the pricing of kagi is rather steep. It is $5/mo for 300 searches a month, which is really going to get you under 10 a day... That's insufficient. Then $10/mo (or $108/yr) for unlimited. I'm curious if anyone knows, are companies like Google and Microsoft making more than $10/mo/user? We often talk about paying with our data, but it is always unclear how much that data is worth. Kag…

$10 felt a bit steep until I realized there is probably the economies of scale at play here. 1) There is a marginal payment overhead. I'd assume $0.50-0.75, leaving their amount down to $9-ish. 2) It's a fairly niche product with a still-small userbase. ~40k users at ~$9/mo = $360k/mo (I know there's $5/mo users and $25/mo users but I'd assume there are far more $5/mo and $10/mo users than $25/mo users) 3) They have…

As the user of a service things like payment overhead, a small userbase, and dev salaries aren't my problem. My only concern is what I'm getting for what I'm paying.

$5 a month for fewer than 10 searches a day is clearly not a good deal. $10 a month might be worth it for some, but an extra $15 a month on top of that for AI results is kind of crazy.

Re: Privacy Pass Authentication for Kagi Search

#86

Post by stebalien »

echoangle wrote: post #72

I don’t really understand how the protocol can ensure that the server can’t identify the client. As far as I understand, the client sends some information A to the server, the server applies some private key X and returns the output B to the client, which then generates tokens C from the output. If the server uses a different X for every user and then when verifying just checks the X of every user to see which one is…

See section 5.5 of the linked paper https://petsymposium.org/popets/2018/popets-2018-0026.php. I'm not sure if/how Kagi implemented this, but the idea is that Kagi's "public" component can be committed to publicly (e.g., in the browser extension itself).

Re: Privacy Pass Authentication for Kagi Search

#88

Post by [deleted] »

echoangle wrote: post #84
voytec wrote: post #73

Earlier quoted context omitted.

[deleted by author]

If the method works as described (which is a cryptography issue and can be verified?), there’s no way to track you. Your claim is a bit like saying „it’s impossible to encrypt mail, the government wouldn’t allow it“. But PGP still exists.

[deleted]

Re: Privacy Pass Authentication for Kagi Search

#89

Post by mortar »

echoangle wrote: post #80
mortar wrote: post #77

Earlier quoted context omitted.

Definitely suggesting the method is secure, assuming the company does all the things they’ll say they do, which I also agree they’ll do. I’m just concerned the government can destroy this all, just by compelling them not to, and change a well intentioned method at any moment.

But what would the government compel them to do? If the method is secure, you don’t need to trust the server. And if they backdoor the open source client, people could notice it in an audit.

The method is secure until they change it. Their docs mention that generating a token is not anonymous, but using a token is. Considering they already know who generated it, it could be trivial for them (to change something server side where the validation occurs, if compelled) to link a particular search to a user.

Re: Privacy Pass Authentication for Kagi Search

#90

Post by jerf »

echoangle wrote: post #72

I don’t really understand how the protocol can ensure that the server can’t identify the client. As far as I understand, the client sends some information A to the server, the server applies some private key X and returns the output B to the client, which then generates tokens C from the output. If the server uses a different X for every user and then when verifying just checks the X of every user to see which one is…

Here's a resource I found that walks through the ideas of the protocol, starting with simple implementations that have a problem, and then solving the problem one by one: https://privacypass.github.io/protocol/

I think that's the best conceptual overview of a crypto protocol I've ever seen.

Post reply on HN