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Re:Duplicate SSH Keys Everywhere by chubot on Tuesday February 17, 2015 @05:05PM (#9065417)
Related: if you don't have enough entropy when creating keys, your public keys might not be identical, but they can share primes. Sharing primes allows this cool factoring attack by DJB and others.

https://scholar.google.com/scholar?cluster=92037504584829650...

This paper explains how an attacker can efficiently factor 184 distinct RSA keys out of more than two million 1024-bit RSA keys downloaded from Taiwan's national "Citizen Digital Certificate" database.

These keys were generated by government-issued smart cards that have built-in hardware random-number generators and that are advertised as having passed FIPS 140-2 Level 2 certification. These 184 keys include 103 keys that share primes and that are efficiently factored by a batch-GCD computation. This is the same type of computation that was used last year by two independent teams (USENIX Security 2012: Heninger, Durumeric, Wustrow, Halderman; Crypto 2012: Lenstra, Hughes, Augier, Bos, Kleinjung, Wachter) to factor tens of thousands of cryptographic keys on the Internet.

Re:Duplicate SSH Keys Everywhere by kerkeslager on Wednesday February 18, 2015 @01:42AM (#9067310)
I almost didn't read the paper because I thought it was only about the batch-GCD method: that's fairly easy to understand. But I'm glad I read the paper because it goes on to explain how using the shared factors allowed them to understand the failure of the PRNG and use that understanding to break keys that didn't share factors, using a more sophisticated attack. It's definitely worth reading that paper.
Re:Duplicate SSH Keys Everywhere by lifeisstillgood on Tuesday February 17, 2015 @06:14PM (#9065839)
Taiwan has a citizen digital certificate process - cool !

I mean that's a seriously big advance over anything I imagined a govt capable of. Estonia was the only other place I heard even close.

And is 183 out of 2 million so bad? Just sign the next round of certificates with this lot and move on.

Re:Duplicate SSH Keys Everywhere by pedrocr on Tuesday February 17, 2015 @06:31PM (#9065922)
Portugal also has a national ID card that's a smart card and includes a key. The last time I tried to use it in the justice ministry website it required accepting a self-signed HTTPS certificate. When I reported the issue I got a "oh, just accept it and it will be fine" response from a supposedly technical person.

So yeah, these things are getting deployed in some places but I'm not too hopeful it will end up being much more than a gimmick. At least I hope not because the next step on the minds of some of these "technical" people is electronic voting and that won't end well...

Re:Duplicate SSH Keys Everywhere by crivabene on Wednesday February 18, 2015 @02:22AM (#9067393)
Italy started issuing smart cards around 2006. Some (not all, you need to request it and takes longer to have it) of the ID cards issued are electronic. They contain a RSA key pair and a X.509 certificate. There are some mandatory use cases, (eg: all documents or emails being transmitted to Governmental agencies must be digitally signed) and some optional ones (you can store fiscal documents as signed PDFs if you don't want to store them physically for ten years). Among regular citizens it has very little use. It has some quirks, but it's a step forward. To boost its usage, the EU should issue a standard and ask every country to adopt it.
Re:Duplicate SSH Keys Everywhere by semanticist on Saturday February 21, 2015 @06:09PM (#9087416)
Not every country in the EU has ID cards, introducing them in the UK has a lot of opposition.
Re:Duplicate SSH Keys Everywhere by kijin on Tuesday February 17, 2015 @08:26PM (#9066467)
And of course there's South Korea, where every financial transaction above a certain amount needs to be signed with an X.509 certificate. Back in the late 90s and early 00s, Korea was a pioneer in the public use of PKI.

But since no browser makes it easy to sign anything with a certificate stored on disk (or in a USB stick), this policy has led to serious dependence on ActiveX plugins (and therefore IE and Windows) that everyone has probably heard about.

Now the Koreans are trying to fix that, but since the government is just as boneheaded as ever, the officially mandated "cross-browser" solution is just a Windows binary that installs NPAPI and PPAPI plugins into every browser. Some variants even work on Linux, but only because they're implemented as Java applets.

PKI is cool in theory. In reality, it's hard to implement it in a way that is accessible to the general public.

Re:Duplicate SSH Keys Everywhere by vbezhenar on Wednesday February 18, 2015 @04:41AM (#9067700)
In Kazakhstan it's achieved by using signed Java applet. It works well in Windows, OS X and Linux. In Linux there are some problems with smart card readers, but generally things work well. I don't like Java applets, but they are probably better than ActiveX.
Re:Duplicate SSH Keys Everywhere by vbezhenar on Wednesday February 18, 2015 @04:36AM (#9067684)
There's similar problem in Kazakhstan. egov.kz is their e-government site. They issued their own root certificate and they use it to sign all users certificates. And they signed their SSL certificate with that certificate which causes it to show alarm.

Not very smart move if you ask me. If you teach users to ignore HTTPS errors, then MITM attack becomes easier because user don't see anything suspicious.

Re:Duplicate SSH Keys Everywhere by lmm on Wednesday February 18, 2015 @06:15AM (#9067909)
It's a dumb move from browser makers (self-signed certificates really shouldn't be the same kind of error as outright fraud). Maybe they can get the Kazakh root certificate incorporated into major browsers? But until then what other approach is possible to bootstrap it? There are obvious reasons the Kazakh government infrastructure wouldn't want to be dependent on e.g. Verisign.
Re:Duplicate SSH Keys Everywhere by pedrocr on Wednesday February 18, 2015 @05:20AM (#9067789)
>They issued their own root certificate and they use it to sign all users certificates.

In our case I think we even have our own CA trusted by the browsers so there's no apparent reason for the self-signing.

>If you teach users to ignore HTTPS errors, then MITM attack becomes easier because user don't see anything suspicious.

That's precisely the point I made to the "technical" person and it was ignored...

Re:Duplicate SSH Keys Everywhere by e12e on Tuesday February 17, 2015 @08:43PM (#9066524)
In Norway there was/is a project that AFAIK originated around the National Lottery's need/desire for smart-card backed digital transactions: https://www.buypass.no/bruker/buypass-id/buypass-smartkort

It's a little unclear to me what the current status is: apparently it's valid for the National (Tax etc) Portal (altinn.no - literal translation: (hand)ineverything.no)). The basic idea was that the Postal service already allow the sending/delivery of registered letters -- so why not just use that for validating the ID. These days mail is largely handled by supermarkets -- and my impression is that the ID check isn't as reliable as it used to be when the postal service operated as a government monopoly.

Anyway, AFAIK, it's still the closest thing we have to working, secure digital ID in Norway.

Re:Duplicate SSH Keys Everywhere by this_user on Tuesday February 17, 2015 @07:50PM (#9066329)
> Portugal also has a national ID card that's a smart card and includes a key.

German ones do something similar since late 2010. The card can be used for online authentication and eletronic signatures (requires certificate that is separately available).

http://en.wikipedia.org/wiki/German_identity_card#Chip

Re:Duplicate SSH Keys Everywhere by sampo on Tuesday February 17, 2015 @07:51PM (#9066332)
> Portugal also has a national ID card that's a smart card and includes a key.

So does Finland (since 2004).

But under 10% of the population has such a card (most people use drivers licence and/or passport as ID), and thus almost no private web services accept it for identification.

Re:Duplicate SSH Keys Everywhere by Sami_Lehtinen on Tuesday February 17, 2015 @11:47PM (#9067025)
Re:Duplicate SSH Keys Everywhere by madeofpalk on Wednesday February 18, 2015 @12:12AM (#9067089)
Don't most countries have ePassports?
Re:Duplicate SSH Keys Everywhere by caf on Tuesday February 17, 2015 @09:04PM (#9066596)
Yes, 183 out of 2 million is so bad, because apart from anything else it indicates that the output of the random number generators used had far, far less entropy than it should.

(How can you use a completely compromised private key as a root of trust for another certificate, anyway?)

Re:Duplicate SSH Keys Everywhere by kalleboo on Tuesday February 17, 2015 @09:18PM (#9066649)
Sweden also has a digital certificate ID, but it was developed by the major banks instead of the government (with the government originally only providing a legal framework to allow digital signatures to be legally valid - BankID is now the primary method to file taxes and manage government services online) http://www.bankid.com/en/What-is-BankID/
Re:Duplicate SSH Keys Everywhere by zhte415 on Wednesday February 18, 2015 @02:38AM (#9067427)
I'm not sure why this is a good thing. An advance would be for not requiring any certification, and not having a single point of failure, despite the tech, as tech will fail, and be subverted before it does [reference: 5000 years of modern history]. A nation without 'citizen' certification system is, to me, cool.
Re:Duplicate SSH Keys Everywhere by abrodersen on Tuesday February 17, 2015 @05:38PM (#9065625)
This is why we can't have nice things. And by nice things, I mean identification of people via cryptography rather than rectangular pieces of plastic.
Re:Duplicate SSH Keys Everywhere by kordless on Wednesday February 18, 2015 @01:48AM (#9067325)
> rather than rectangular pieces of plastic

Finally, the U.S. gets a mention.