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Does Your Company Use a PKI Solution?
punkrokk asks: "I am doing an Independent study of the feasibility of a Microsoft Certificate Services PKI in a distributed company. So far, it appears from my research that MS has the best supported implementation of a X.509 based PKI solution, for the Windows environment. While there are a few major weaknesses in a X.509 Public Key Infrastructure, one of which being Certificate Revocation Lists, using one is better than nothing. You do get a tangible security benefit, in addition to doing switch port authentication, and VPN quarantines. The problem is the cost of implementation is pretty steep, from the planning side. What do you guys do for dual factor authentication? Has anyone had Verisign sign their Certificate Authority? If you have implemented a MS Certificate Service infrastructure, I would appreciate your comments."
The University of Wisconsin - Madison has deployed a campuswide PKI solution based on GeoTrust.
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More information, with presentations and descriptions of our deployment:
http://doit.wisc.edu/middleware/pki/
UW/GeoTrust/EDUCAUSE joint press release:
http://doit.wisc.edu/middleware/pki/geotrustuwpki
For more information about UW-Madison's PKI deployment, contact Nick Davis
We have been using MS' Certificate Services for a couple of years - primarily for WPA-RADIUS authentication. It has worked fine. You can set group policy to automatically request user and machine certificates so there isn't a lot of touches to the desktop. Only thing I haven't figured out is how to get our company's root CA to be a trusted root certificate within the WPA config.
If you're going to expose your encryption method using a public key, you're about as safe as a CTU agent travelling with Jack Bauer and Tony Almeida. In other words, just think of yourself as Ensign Johnson beaming down to the planet with Kirk and McCoy.
Security is good, but only as good as the weakest link in the chain. If you have humans working for you, they are the weakest link. It's a lot like a car with a flat tire. You should change to the spare, but realistically, the spare is probably a small tire that isn't really designed to be run on for long distances and will cause you to lose control if you rely on it too much.
In a word... no.
We use Certalert for managing our digital certificate lifecycle and CRL's. This is a nice add on solution to MSFT PKI. This does not do anything on the 2 factor authentication side however, so we are still looking for a solution there. For my money the Certalert guys really provide a great solution for managing your server side certificate environment. http://www.certalertsoftware.com/ ,if your interested.
...and misread it as "does your company use a PK solution?" ...yeah, I wish they would... some PKing around the office might not be a bad thing.
Don't forget to look at OpenSSL (you'll have to write some scripts and use a RDBMS with this), Entrust, and RSA.
Also, don't hardcode your CRL URL into your certificates. If that web server goes down, your entire PKI could break. It is better to leave revocation out of certificates and get all of your important PKI clients to use OSPF.
For the root node of your PKI:
Take a laptop, scratch off all networking-type thingks (modem jack, ethernet jack), generated your root CA key, use it to sign your intermediate CA certificates, then lock the laptop in a safe.
A slashdotter who didn't build his own computer is like a Jedi who didn't build his own lightsaber.
Hi, I am going through Microsoft's 'Step-by-Step Guide for Setting Up Secure Wireless Access in a Test Lab' now, and the solution does not seem very simple. To setup 802.1x you need: - Active Directory (usually, but you could use standalone IAS) - IAS service (MS's RADIUS server) - Access policy on IAS setup for 802.1x - Certificate server, with computer certificate issued to the IAS server - AP and wireless client that supports WPA Enterprise. - Patches on the client to give operating system support (e.g post sp2 patch to support WPA2). Then, when you configure the client, and connect it seems kind of clunky with popup's for entering credentials and others to verify certificates. Do third party solutions make it simpler, or just outsource the Certificate Services part?
For some internal (non user-facing) things I have used a self signed cert; for example when prototyping cosign (web single sign on).
In the past we have rolled out a CA signed by CREN. This was a pretty small rollout and used for just Shibboleth, S/MIME, Web Auth, and some limited classroom work using handheld devices. At this point we are using mostly Thawte Freemail for S/MIME and CACERT for S/MIME, PDF signing, 802.1x, and a odd series of other tests/work.
This is less than ideal since we end up beholden to corporate groups, but there is something good on the horizon, USHER Usher is a higher ED CA being put together by Internet2 which will be cross certified with the Federal CA bridge. Basically what CREN was supposed to be, only with more backing and interest.
The nice thing about it is that we will get a signing cert to use at will rather than paying someone like Verisign per certificate which is not gonna happen with 138,000 users, especially if we wish to do any kind of PKI-LITE setup (where short term "junk certs" are issued on demand eliminating the need for a CRL which nobody has figured out how to do right yet).
I did a fairly extensive pilot of this at my previous company, with the assistance of Microsoft. We demonstrated everything you mentioned successfully and did scalability tests that indicated that with careful planning, we could scale it to serve our needs (~100,000 users). We used the Active Directory integration, which made issuing and revoking certs seemless for the Windows users (most of the desktops). The primary application was WLAN security, but we demonstrated everything from SSL certs to application signing. We also used the Safenet CA3 hardware root key device as well. There is a *lot* of planning required to make this work well, but it does work.
My company believed that we had a private key infrastructure, but it seems that our moss green frog hide-a-key was a layer of deception far too easily pierced by even the most novice criminal mind...
we now use a terra-cotta sleeping bunny key safe and feel much more secure.
Entrust wrote the first commercially available PKI back in 1994, and have only improved on it since then. It's scalable to millions of users, and is used by many governments on financial institutions. Worth a look if you are looking for a large enterprise PKI solution.
Life is like a web application. Sometime you need cookies just to get by.
I strongly recommend you research Novell's PKI solution -- it's integrated directly into Client32 (the network client software) for Windows, and the key, certificate, etc., are all stored in the Directory (formerly known as NDS {Novell Directory Services}, it was renamed to "eDirectory" quite a few years ago).
"NICI" and "Directory Services" and "NetWare" are the keywords which will be most helpful in your search for additional information on this subject.
The Lumber Cartel, local 42 (Canadian branch)
British Columbia, Canada
I have used OpenSSL to set up Certificate Authorities for military testbeds prior to, and coinciding with, their own PKI rollout. There is no cost associated with its use and once you learn how to use it, it is very easy to use. OpenSSL creates and signs standard X.509 certificates that work with any browser, webserver, or email program that utilize such certificates. You can set up CRLs and such easily as well.
OpenSSL is very powerful and useful. I have used it for many of its encryption routines (such as locking up my pr0n collection while I am in the Middle East!).
strike
"Someone needs to talk to the tree of liberty about its ghoulish drinking problem." by ohnocitizen
But I know if we were to implement some sort of security solution we'd go straight to Microsoft for a fairly priced product from a company with a proven track record of putting security first.
US DOD is probably the single largest user of PKI in the world.
We (Navy via NMCI) use multi-factor identification. Most commands have CAC cards (basically just smart cards) that store multiple keys (one for email, one for web pages, one for digital sigs). To access any data on the cards (including certs) you also need a PIN. Furthermore, most systems have an additional (strong) login uname/pass after your cert is accepted. The result is password overload but fairly decent security.
You minimally have dual authentication factors (physical card access and PIN) and is most cases triple authentication.
Dunno if this will get modded out of AC-land, but here goes:
For the newbs, CRLs or Certificate Revocation Lists are nothing more than lists of which certs have been revoked. If you're going to deal in non-physical access tokens (as opposed to, say, metal keys and RFID badges) you're eventually going to want to deal with the eventuality that people's lifespans are generally longer than the amount of time that they have access to your stuff. PKI is excellent for mathematically proving that noone that can't factor huge primes can get your secrets just by looking at bits on the wire, but you can't really demand that your recently fired employees surrender their keys since they could very well have made copies in advance. Now that I think about it I suppose the same is true of keys, so consider CRLs the digital equivalent of changing locks.
A CRL is a list of all they key IDs of keys that have been revoked. If you get terminated, you go on the list, and when you subsequently try to use your key, even though mathematically it works great, if you're on the CRL you get a 403 (or big guys with guns or whatever your model for Access Denied happens to be).
CRLs are as dead end as it gets. Especially if you're working with a lot of end-devices or end-users, your CRL situation is going to get fantastically out of control very quickly. Picture, if you will, the DoD. How many people do you think had keys last year who aren't entitled to them now? Sure, the really old keys expire, but the new keys that were revoked all have to be downloaded *every time* a user makes a query, or else you risk race conditions of varying severity. (One could easily imagine the race to get home and log in over the VPN to copy the Secret Plans after being fired; the amount of time a user would need to do this is about the longest you'd want to go between CRL updates. If a CRL was many megabytes large and if the authenticating device got many hundreds of requests per second you might have a problem.
OCSP , or Online Certificate Status Protocol, is a huge step in the right direction; instead of downloading the entire CRL to the authenticating device, the device instead makes a quick call to a OCSP responder, querying the status of the cert. The OCSP has a store of CRLs which it obtains from the CA/VA, and can create a signed response containing the status of the certificate: good or revoked (or, I suppose, unrecognized or otherwise munged). Now you only have to distribute CRLs to one/several devices, instead of every one in the infrastructure.
Some groups (Corestreet, among others) have created distributed versions of OCSP which use precomputed proof lists in order to avoid the problem of distributing private keys to a network of distributed OCSP responders for use in signing OCSP responses. This D-OCSP is vastly more powerful and flexible than CRLs (and proportionally expensive).
PKI is a pretty daunting challenge to implement correctly, and its even harder to make the other links in the chain nearly as strong as the crypto. Best of luck.
vvj
Disclosure: I'm the Principal Engineer for Red Hat Certificate System. (Previously known as Netscape Certificate Management System).
Our product is fairly widely deployed. For example, every single one of the 18+ million Certificates issued from the US Dept of Defense CAC (smartcard) deployment use our Certificate Authority. There are many other deployments within the Federal government also.
In addition, someone mentioned Geotrust. Geotrust built their certificate issuance service on top our certificate authority, so of course I think very highly of them.
Our product is an enterprise-class (meaning hugely scalable, and fault tolerant), full featured, mature product, written by engineers with many years experience in the PKI field.
But, I would like to turn the question around - If you haven't deployed a PKI yet, what is stopping you?
As an example, one of the deployment-blockers we found in the past few years was the poor integration PKI management systems (Certificate Authorities) had with Smartcard Management Systems. So, we engineered a smartcard management system, and bundled into the Certificate System at no extra cost.
What applications would people like to see PKI-enabled that aren't already?
And since I'm a Red Hat employee now, I am constantly thinking about integration with Red Hat Enterprise Linux and Fedora - so, what changes would you want to see happen?
I do security work for a Fortune 100 company, and while we've got the usual SSL certs on some of our web servers, we haven't yet had a compelling business case that would justify the huge expense to do PKI right. Coupled with the belief that PKI done wrong is worse than not doing PKI at all, we've stuck with point solutions for our encryption needs thus far.
I believe that we're moving forward with certs in the ActiveDirectory to facilitate EAP-TLS on our wireless, and that will probably go farther towards "universal" certificates for our end users, but since rolling out smart card readers to tens of thousands of users will be a significant investment, using certs for regular auth to the AD just isn't cost justified yet.
In the mean time, we've got self-signed certs for signing internal applications, and use some commercial, GPG-like software for desktop/email encryption :-) SSH works quite well for shell access, although the onesie-twosie management of the RSA keys is a major bitch.
In reality, I doubt that we'll ever go for a full-blown PKI done right. Every time we look at it, we figure out that the servers, admins, training, and physical security improvements will cost $6 million, and it won't really buy that much. For important authentication things, especially remote access, using those random-number tokens works really well, and doesn't have nearly the costs associated with them that PKI does.
Regarding the use of the CRL distribution point extension, a URI that points to a DNS alias can help alleviate the risk.
"OSPF" was likely a botched reference to OCSP (Online Certificate Status Protocol), defined in RFC 2560.
Finally, read the PKIX spec on certificate management, RFC 3280. It will give you a much more detailed understanding of how PKI should work than any vendor docs. This level of understanding is critical if you start playing the role of CA.
If you do your homework, and understand how things work, OpenSSL is an adequate tool.
Although MS may have a bastardized implementation of PKI, it has some primary flaws. For starters, MS will only allow their domain controller certs to be constructed in some specific fashion. If you are a small firm and it is inexpensive to gut your PKI quickly, then play with MS implementations.
Stick with standards compliance for larger implementations. You never know how someone is going to need to use your infrastructure, and it is a REAL PAIN to adjust (bigger = exponentially harder). For example, one day you might need to do something with hardware cards or trusted peers. If your chosen version doesn't play that way, you could be screwed. Just find another job, fast.
If all you want is single sign on with a piece of plastic, buy a SSO solution and be done with it. But if you want a root CA, subordinate CAs which issue hardware, software, server, and mcs credentials, then that's a real PKI.
If you don't have the facilities to handle physical security needed for a PKI, then find a vendor.
The first part of PKI is Policy (read - legal junk that gives your Base64 blobs some sort of validity). You need a CP and a CPS and that requires a lot of typing. Once you get that down, then you can survey offerings and find what you need. Some hints at decent products are from Novell and a section of RedHat that was formerly known as NSS.
I'm not stricly MS bashing, but some will see 2 linux vendors and say "oh, he just hates Windows". Fact is there are plenty of PKI standards and Microsoft doesn't do it correctly - why should they when everyone uses Windows to sign in.
I sure hope you are not working on HSPD12PKI and other names for encryption like encryption, lock etc. are stupid names. What should be done to advance its adoption is to have a put in envelope button and an open envelope button. This way it hammers the point that email is a post card and if you have something you don't want the world to see, you put it in an envelope. It is a paradigm that translates well from the real world and makes much more sense than lock and unlock or encrypt and decrypt.
just my 2 cents.
The war with islam is a war on the beast
The war on terror is a war for peace
I honestly think that, after 20 years of PKI "about-to-take-off" that the tipping point isn't going to come from corporations: It's is going to come from customers, most likely of Paypal or Ebay or CitiBank or Bank of America or Walmart or CVS or Postal Service or whomever (RadioShack?).
What will drive this will be developing and promoting a decent public PKI system. "Stop by the Customer Service Counter with enough ID and someone (with a bit of training) will certify you for a "Trusted Customer Card & Code" today!"
Then all of the good things that folks promise about PKI can be told/sold to J. Random Customer, and it'll be cheaper then a toaster and as valuable as their customer affinity card.
As a marketing tool it'll be high profile, moderately high contact, and likely with enormous retention. Sure there's an educational aspect but the press can handle that, every article will just bring that much more brand-awareness. Wanna verify my online whatever? I use Brand A!
Roll out a free plugin for the top 5 email clients and the lead will be impressive. It's techie, it's "smart", it'll be like recycling without having to deal with material objects.
Sorry, I know it all seems implausable, but when public PKI gets going I think it'll be bigger then "search" & "portals" and a lot "stickier".
I don't read ACs: If a post isn't worth so much as a nom de plume to its author then I wont bother either.
You seem to be asking several questions, or confusing several solutions, or both.
.1X schtuff up.
If you're looking for port-level authentication on your networks, wired or wireless, then IEEE 802.1X is the answer.
(dot)1X uses EAP (Extensible Authentication Protocol) Methods. MS gives you two big methods out of the box w/ the XP client: PEAP-MS-CHAPv2 (think: login/passwd) and EAP-TLS (think: digital certs), and provides the server level support in the form of certificate services, IAS (internet authentication server) and integration of both into the AD. Other methods are around, typically from other vendors (at additional cost). To impliment one not supported by MS out of the box, you need client-side and server side support.
IF (BIG IF) you have an MS infrastructure, your client machine logins are probably hanging off the domain controller, and use one of the above methods, or, can easily (and transparently to your users) move to one.
NOW, once either one is in place, implimenting port level auth is straightforward.... unless you do not have 100% XP clients. Nobody does in my experience (think: Printservers, other headless network clients). Then you get to get REALLY inventive with firewalls, vlans, switches, etc. and you can "get there". Taint gonna be easy....
There are open solutions on the client side, even in an MS infrastructure. Google for "wpa_supplicant".
NOW, back to your question: The MS PKI will prolly scale as well as AD itself. No better, worse.
This answer is deceptively simple. You have to overlay it on YOUR network, YOUR security policy, YOUR needs, YOUR level of expertise, etc.
MS does eat their own dawgf00d in this area, and I personally know some of the architects and implementors.
I AM NOT A MS FAN. That being said, they have (mostly) gotten this right.
There is a book from MS Press: Deploying Secure 802.11 Wireless Networks with Microsoft® Windows, ISBN: 0-7356-1939-5, which is obviously oriented on wireless nets, but which steps you through setting all of the
Recommended....
I sincerely hope this helps..
-RED
Fashioning it in Windows is quite simple, as Windows domain participants will automatically enroll for the types of certificates that you want, for example, allowing the machines to authenticate into the domain silently. I've written several detailed implementation how-tos on these subjects (kafkaATtelusDOTnet, if you're interested).
As soon as you leave the Windows world, then all these things become a bit trickier. No longer can you simply let the the Windows Certificate Services generate your certificates silently, since you'll need to intercede to generate the type of certificates that want. Controlling how these certificates are constructed becomes somewhat difficult (not impossible, just tricky). How and what you want will totally depend on the applications that you're using. You're probably far better off getting a PKI solution based on OpenSSL in that case, especially if you need to interoperate with non-Windows applications and devices (such as CISCO routers). If you don't have time to write any code, look into RSA Security. They're wayyyy cheaper than Verisign, and you don't have to deal with the hassle of outsourcing.
Another poster recommended using OCSP - thats fine, but I don't believe there is a native OCSP client built in to Windows. You either have to roll your own, or obtain one (RSA, for example, has one. As well as Computer Associates OCSPro). In fact, there is no reason why you can't implement both redundantly. Use both the CRL distributionpoints (CRLdP) extension *and* the AIA extension to get this done.
Another citation, I believe, referred to Peter Guttmans (very old) document on various PKI implementations, X.509 Style Guide. This document is horrendously outdated, as the tools and apps are far more widespread than they were wayyyy back in 2000.
Anyways, for what its worth, if you know what you're doing PKI has distinct advantages to add to your electronic security (although a blind reliance on it won't help you at all).
If you don't know what you're doing, then you'd better go with a vendor that will support you.
When you need to do authentication with parties outside of your organization you probable need to use a commercial CA such Verisign, but for internal use within your organization there is no need to do so. Personaly, for internal authentication I prefer to use a CA generated on one of our servers. It makes it easier to secure a VPN, for instance, if you own the the CA that signs the certificates that authenticate connections. The OpenVPN package provides a very comprehensive set of openssl tools that allows one to generate various certificates on Linux, Unix or Windows systems.
I have been working with various PKI implementations since 2000, and I have two bits of advice for any new PKI deployment:
- PKI is not an end in itself, it is just a tool: before designing a PKI solution, you really need to know exactly what end solution you're trying to put in place: Windows Logon? VPN Access? Device authentication in your infrastructure? Email encryption/signature ? Web authentication? Once you know the requirements of your end solution, the choice of a PKI as a security layer for that solution will be far easier.
- The technical solution is the easy part: as can be seen on the other posts, there are plenty of Certificate Authorities around, all with their technical strenghts and weaknesses. What they do not address is the process part around PKI - the CP/CPS and others -, in other words how the PKI shall be used, who is allowed to do what, how the various components shall be protected, procedures defined to address various scenarios (administrator run over by a bus, role separation, administration procedures, key ceremony, key escrow, revocation policy, etc.). This is really the tricky part because it is what will make your PKI a really strong solution or just a gimmick...
As a conclusion, in some cases the Microsoft CA will be fine (say you mainly want to do smart card logon on a 'standard' Windows network), in other cases other solutions will be more suitable, but in every case, the hardest part (as in 'the most expensive part') will be the creation of the policies revolving around your PKI. If after analysis you find out a strong PKI policy does not seem that important in your particular case, chances are you don't really need a PKI but another form of strong authentication. For instance, 2 factor Auth based on one time password tokens or similar, which are much lighter to put in place from an admin point of view, though not quite as strong as PKI, of course...
Just my 2 cents,
Edouard
Switch port authentication? You don't need a certificate to authenticate someone plugging into your switch port. Just look at the dude and see you recognize him.
Although I guess we could pin our public keys on our shirts like nametags and walk around that way.
Actually we just switched AWAY from MS cert services to an outsourced CA. I did this because we primarily used the MS CA for smartcard logins, and I was able to get one of the FREE online CA's to support the required configurations.
Because they have passed their webtrust compativle security audit, they will soon have major browser inclusion. Thus we will soon have a single cert that can be used for email encryption, IM encryption using certs using Simp ( http://www.secway.com/ ), and SmartCard logon to the network.
1. I installed PHPki and used it as a CA,
2. Generated oodles of certificates for our entire staff (SMIME certs, so they work with Outlook 2K and 2K3)
3. Published each of their certificates to the Global Address List
4. Had everyone set the option in Outlook to include their public cert as an attachment to signed/encrypted emails
5. Had everyone install the CA's root cert on their machine
Now they can send eachother signed and encrypted emails, all WITHOUT any kind of Microsoft CA or server. It's important in our environment that the private certs NOT be stored where the email/Exchange admins have access to them, so while it takes a little manual labor, it's FREE and works very very well.
With the first link, the chain is forged.
We need PKI at my company, but there's a big problem.
The people who would be responsible for keys, can just barely handle email.
I know I'm not alone, and I know I'm not the only lone admin who would have to be responsible for put such a system in place, and have to hold hands & train users.
I have researched my eyes out.