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Comment Re:Boring (Score 2) 141

1. Actually, revocation checking does not solve the problem, alteast if someone had the CA private key, they could generate the same ID's as other existing certificate. OSCP/revocation lists only checks id's not names, which makes it not useful for all possible problems.

Neither CRLs nor OCSP are intended to mitigate a CA private key breach.

The only control in the system is to revoke the CA root and that can be effected on Windows by issuing a new CTL (as happened to revoke the Diginotar root) that drops the compromised root. The other browsers have similar mechanisms.

2. I also think DNSSEC can be useful, it would be really helpful for the domain-owner to be able to make it clear that his website uses cert X and cert Y (which implies CA A and CA B). And not any other cert or CA. Deployment of DNSSEC is very slow though at the moment.

The war could well be over by the time DNSSEC is deployed. The Iranian group have developed new attacks and dramatically escalated the sophistication of their attacks. The time between attacks has been weeks, not years. There is simply no prospect of large scale DNSSEC deployment in the next 6 months. the Iranian 'elections' are in March. I can't even see any possibility of deployment ahead of the next presidential election.

We need at least 2 things: - a fallback method that browser makers want to adopt where DNSSEC hasn't been deployed by the ISP or when you are stuck in a "hotel network" or your OS does not support and so on. Because the browser needs to get the keying material to be able to check the if the data is properly signed. It do not think it even matters where it got it from, any old fallback channel might probably do. For OSCP http is used, so maybe that is good enough here too ?

Working on both of those.

- much better industry support for automating the keyrollover communication with TLDs. If I get my domain at some provider and run my own DNS-server there is hardly any provider, if any, which support EPP or whatever to communicate my DS-record to the TLD. Many TLDs that have deployed some DNSSEC don't (yet) even support DNSSEC in their EPP from their direct customers/members.

3. Can you be a bit more specific about what you proposed in 1993 ?

Not without sounding really whinny.

At this point its water under the bridge, I have changed my mind on what the approach to security should be and so has the industry.

The browser that an Iranian dissident should be using is probably not the same as the one your granny uses to shop online for sex toys. There are security concerns in both cases but the risks and issues are totally incommensurate.

Comment Re:There are always tradeoffs (Score 2) 141

No seriously, the "trust" in "trusted third party" has nothing to do with the trust that you put in the second party (i.e. the server or business with which you are communicating). It has all about to do with the trust you put in the third party (the certification agency), that it correctly does its job (only giving certificates to properly identified entities and appropriately securing their infrastructure so that hackers and spies can't just "help themselves"). The threat that SSL certificates are supposed to protect against is wiretapping, not rogue businesses. I'm sure, all of those shady banks that failed in the 2008/2009 crisis had valid SSL certificates, and rightly so!

Let me explain. I have been working on Web security now for 19 years. I was present at the original meetings at which the SSL system was proposed, I convened several of the relevant meetings.

At no time was government wiretap a design consideration for SSL. NEVER. In fact to claim this was totally ridiculous since at the time we were fighting a running battle with the FBI and the NSA who were trying to stop us using strong cryptography at all. The original SSL design was limited to 40 bits and was very clearly crackable.

SSL is not designed to be wiretap proof, my proposal and the EIT proposal were stronger in that regard. But at the time the criteria was whether shopping online could be made as safe as shopping in a store. That was the design criteria by which SSL was judged and the design criteria it passed (after they eventually hired some competent crypto people). I was the person who stated the design criteria at the meeting.

Comment Re:And how much software checks for revoked certs? (Score 1) 141

Most check CRLS and OCSP.

The problem is what they do when they can't reach that data. All the browsers out there now simply fail silently and go to the site anyway.

For some reason this is seen as a problem with CAs and not the broken browsers. But from the browser providers perspective 99% of their customers are really interested in getting to sites reliably and without fuss and less than 1% are dissidents whose lives might be threatened.

This is not the fault of the guy who writes the code. They only own one small piece of the browser and do not get to make the 'commercial' decisions.

Expecting this to be any different with a DNSSEC scheme is to engage in mystical thinking of a naive variety.

Comment Re:Boring (Score 3, Interesting) 141

Unfortunately the registrar system is rather less trustworthy than you imagine. We have not to date encountered an outright criminal CA. We do however know of several ICANN registrars that are run by criminal gangs.

The back end security model of the DNS system is not at all good. While in theory a domain can be 'locked' there is no document that explains how locking is achieved at the various registry back ends. A domain that is not locked or one that is fraudulently unlocked is easily compromised.

The part of the CA system that has been the target of recent attacks is the reseller networks and smaller CAs. These are exactly the same sort of company that runs a registrar. In fact many registrars are turning to CAs to run their DNSSEC infrastructure since the smaller ones do not have the technical ability to do it in house. In fact a typical registrar is a pure marketing organization with all technical functions outsourced.

There are today about 20 active CAs and another 100 or so affiliates with separate brands. In contrast there are over a thousand ICANN registrars.

Sure there are some advantages to incorporating DNSSEC into the security model. But to improve security it should be an additional check, not a replacement. Today DNSSEC is an untried infrastructure, it is grafted on to a legacy infrastructure that is very old and complex and security is an afterthought.

The current breach is not even an SSL validation failure. The attacker obtained the certificate by bypassing the SSL validation system entirely and applying for an S/MIME certificate that did not have an EKU (which it should). That makes it a technical exploit rather than a validation issue. DNSSEC is a new code base and a very complicated one. Anyone who tells you that it is not going to have similar technical issues is a snake oilsman.

Comment Re:There are always tradeoffs (Score 2) 141

DNSSEC has its place, even for key distribution. But it does not provide a basis for trust because mere holdership of a DNS domain does not mean you are trustworthy.

The big win for DNSSEC is to distribute security policy in a scalable fashion. See my CAA and ESRV Internet drafts.

Imagine that you are visiting slashdot, wouldn't it be better to use SSL than en-clair if the site supports it? Wouldn't it be better to have encryption with a duff cert than no encryption at all? [*]

DNSSEC allows a site to put a flag in its DNS to say 'always use SSL when visiting slashdot on http'. Now the server knows that if it is going to slashdot and it is not encrypted there is a man in the middle. Same for Twitter, Google etd.

DNSSEC can also be used to ensure that the only certs trusted for a domain are ones authorized by the domain holder. This provides an independent trust path to CA issued X.509. If used in combination, security can be improved.

[*] The catch is that showing the user the padlock icon for a duff cert is going to make them less secure. That is why I would like to see the browsers remove the padlock icon completely for DV certs. the only reason the padlock is required is to allow the user to check that SSL is in use. Since the user can't and won't do that reliably it is a poor control anyway. But it is in any case a control that should be enforced by the browser not the user and DNSSEC security policy allows that to happen.

On key distribution, well sure, for typical Web services and for promiscuous security, DNSSEC validated keys are just fine. It is not going to be a money saver. It does not justify a padlock icon (neither does a DV cert). But it is perfectly adequate for most applications.

Unfortunately it is likely that making use of DNSSEC for key distribution is going to be delayed for at least a year due to IETF politics. I blame the people behind the DANE proposal. They have been less than forthcoming about their real agenda from the start and have shown absolutely no willingness to accept any input from other parts of the IETF. The IETF is a consensus based organization but the test is IETF consensus, not working group consensus. If a clique wants to change the rules for handling PKIX certs they have to get an IETF consensus that this should be done.

DANE could have easily been designed in a way that allowed security policy and key distribution to be completely separate. Unfortunately the ruling clique insists these be joined. The result is a spec that is in my opinion undeployable because the transition strategy for a scheme providing positive trust (key distribution) is by necessity very different to that required for a scheme that provides negative trust (key revocation, security policy, etc.).

Comment Re:Boring (Score 3, Insightful) 141

Oh I know what he is trying but he has no clue what the threat model is.

The threat model in this case is a well funded state actor that might well be facing a full on revolution within the next 12 months. It does not matter how convergence might perform, there is not going to be time to deploy it before we need to reinforce the CA system. [Yes I work for a CA]

I think it most likely we will be seeing the Arab Spring spreading to Syria with the fall of Gaddafi. We are certainly going to be seeing a major ratcheting up of repressive measures in Syria and Iran. Iran knows that if Syria falls their regime will be the next to come under pressure. In many ways the Iranian regime is less stable than some that have already fallen. There are multiple power centers in the system. One of the ways the system can collapse is the Polish model, the people of Poland didn't have a revolution, they just voted the Communist party out of existence. If the Iranian regime ever allows a fair vote the same wil happen there.

Anyone think that we will have DNSSEC deployed on a widespread scale in the next 12 months? I don't and I am one of the biggest supporters of DNSSEC in the industry. DNSSEC is going to be the biggest new commercial opportunity for CAs since EV. Running DNSSEC is not trivial, running it badly has bad consequences, the cost of outsourced management of DNSSEC is going to be much less than a DNS training course ($1000/day plus travel) but rather more than a DV SSL certificate ($6 for the cheapest).

The other issue I see with Convergence is that it falls into the category of 'security schemes that works if we can trust everyone in a peer to peer network'.

Wikipedia manages a fair degree of accuracy, but does anyone think that they really get up to 99% accurate? Until this year the CA system had had three major breaches, all of which were trapped and closed really quickly plus about the same number of probes by security researchers kicking the tires. Until the Diginotar incident anyone who had revocation checking in place was 100% safe as far as we are aware, not a bad record really.

There is a population of about 1 million certs out there, even 200 would mean 99.95% accuracy.

Running a CA is really boring work. Not something I would actually do personally. To check someone's business credentials etc takes some time and effort. It is definitely the sort of thing that you want a completer-finisher type to be doing. Definitely not someone like me and for 95% of slashdot readers, probably not someone like you either.

The weak point in the SSL system is not the validation of certs by CAs, they are (in order) (1) the fact that SSL is optional (2) the fact that the user is left to check for use of SSL (3) the fact that low assurance certificates that have a minimal degree of validation result in the padlock display.

The weak point being exploited by Iran is the braindead fact that the Web requires users to provide their passwords to the Web site every time they log in. I proposed a mechanism in 1993 that does not require a CA at all and avoids that. Had RSA been unencumbered I would have adopted an approach similar to EKE that was stronger than DIGEST but again did not require a cert.

Certs are designed to allow users to decide who they can share their credit card numbers with. That is a LOW degree of risk because the transaction is insured. Certs are not intended to tell people it is safe to share their password with a site because it is NEVER safe to do that.

Comment Re:It depends on contracts (Score 5, Informative) 243

The typical recording contract of that era was expressly designed to avoid being categorized as 'work for hire' as it would mean a shorter copyright term. The recording contracts were also designed to bilk the artists out of their royalties by requiring them to bear a very long list of costs. Work for hire has a very specific meaning in copyright law. The labels can't redefine the meaning retrospectively. Or at least they can't unless they can bribe Congress to do it for them.

Comment Re:"We own it" (Score 3, Interesting) 566

The article is incorrect. Microsoft does not ban 'open source', it bans one very specific type of license that the author expressly intends to be viral.

Microsoft use open source code, but they only use code with licences that do not have a viral clause. They use some of my open source code in IE. Microsoft also publish open source code, but not under viral licenses. RMS is very definite about his intention to contaminate proprietary code with his own.

Now before folk go off into a slashweenie froth over this. I know RMS, i have argued this point with him. And he is very very clear about his intent that the gpl be viral. He makes no secret at all about this. Go and talk to him if you do not believe me. But dont assume that because the description of his idea sounds nutty that it must be false. Again, you need to talk to him and know him.

We expressly rejected the gpl for licensing the CERN web code because we did not want the ideological baggage. The code was merely a tool to spread the web. Well ok not for Tim, he hadvcode attachment, but not to owning it. We did make a big mistake in making the code public domain, but there was not the selection of licenses we have today. BSD would have been a better choice.

So dont blame Mr softy for taking RMS seriously. There probably isnt a legal risk there. But Gates is merely taking RMS seriously.

Comment Re:That's War (Score 1) 415

Vigilantism is wrong

That is why anonymous should be behind bars and so should anyone from Themis who has broken the law as proposed in this document.

the attacks proposed were against wikileaks, not just anonymous. There is no evidence wikileaks has broken us law. So this is not even vigilantism, it is a criminal attack.

Comment Re:Government fraud (Score 4, Informative) 415

They are self confessed liars. So why accept the claims of vandalism at face value?

I am at RSA, I was part of a long conversation with Art Coviello last night and he did not mention it. It his his confernce and it is a security conference. If the ckaim was true and had been reported i would have expected it to be mentined.

I think it rather more likely that they did not have the courage to show their faces.

They have been punked for a start. That is an embarrassment. But what would make them pariahs was the proposal to engage in criminal attacks and political misinformation. Many of us are ex law enforcement or ex intelligence. Others work closely with them. You cant do that if you are committing criminal acts yourself.

If i thought there was a chance he might show his face i would have gone to his session earlier. But that was never likely.

Last year he was talking about hacking online games and club penguin.

Comment Re:But then what kind of asshole (Score 0) 371

Hah! The Tea Party wants less government interference, not more..

No, all they want is to be told that they are absolutely right about everything and that they have a complete and infallible system of the world that only morons and the corrupt could possibly disagree with.

So really no different from Communists, Fascists, Moonies, and other cultists.

And the fact that the Tea Partiers talk about freedom all the time means precisely nothing. Karl Marx talked about freedom. So did Lenion, Stalin, Hitler, Mao and pretty much every other demagogue. And before he became Chancellor, most Germans regarded Hitler with pretty much the same disdain as Glenn Beck is considered.

When people talk about 'second amendment solutions' or the 'ammo box', what they are talking about is the murder of their political opponents. I don't draw comparisons with fascists and Stalinists lightly, but talking about murder of opponents crosses that line completely.

Whether or not Loughner's action in Arizona was a consequence of Palin and Beck's rhetoric can never be proved or disproved. But what is beyond dispute is that 1) that type of rhetoric can lead people to murder, 2) there is ample evidence that Palin in particular intended to use that rhetoric in order to intimidate her opponents, 3) no member of the Republican party leadership had the courage or the principles to condemn the rhetoric when it was being used.

So no, I don't think that the consequence of a tea party government would be less regulation or government interference. The people simply don't have the knowledge or experience to form a coherent policy, let alone implement one. What would result would be an increase in regulations that protect the interests of narrow cliques that can manipulate the party and a decrease in regulation that serves the public interest.

People can be totally self-deluding. Back in the 19th century the power elites believed that 'rain follows the plough' despite ample scientific evidence to the contrary. Now they want to believe that free markets are automatically self regulating and that climate change is not occurring.

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