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"Fast Packet Keying" Improvements to WEP
Weedstock writes: "BBC Tech News has an article about the latest development in wireless networking security. It seems that RSA Security has improved the encryption system used by the protocol. Will this new update finally make wireless networking secure? You can also find a list of papers about wireless security issues here." RSA has a press release about their changes to WEP being accepted by the 802.11 committee.
My own view is simple; encryption shouldn't be done at the hardware layer. Assume that everything on the network is wide open and use SSH / SSL on each protocol or an encrypted VPN.
:)
This way you can be sure everything is encrypted consistently from the host machine all the way to the client, even when your packets pass through 'unknown' equipment.
The other advantage of this approach is that you can get all your hardware cheap on ebay because everyone else is abandoning them as 'not secure enough'
455fe10422ca29c4933f95052b792ab2
Offtopic, but here is a link for a project to attempt converting 2.4 GHz 802.11b wireless LAN cards down to the 900 MHz band to help overcome non line-of-sight issues.
here's the link
I'd like to know that too, but for my WaveLan cards. And if it can't be upgraded, I want a refund on the $20 extra per card I paid to get "128-bit" (yeah, as if) encryption.
not unless it's a firmware update that fixes all current equipment. There is alot of 802.11b stuff out there. much of it is 24-40 bit only. Most everyone using it hasn't a clue about firmware updates or even security problems for that matter (The sheer number of open 802.11b networks I can snif that have no encryption is proof of that.
They need to make this a part of the driver and make the driver force a firmware update and enable it by default if securing wireless is important. Otherwise this is only an expected feature of the new stuff that I'll buy in about 2-3 years.
Do not look at laser with remaining good eye.
I wonder... The press release quotes a PhD from Hifn and a marketing droid from RSA, and says that RSA and Hifn developed this together.
I know RSA's the big name here, but I wonder whether they merely contributed the name, not the research.
-Billy
The argument against IPSEC and for wireless link crypto is based on the perceived overhead of forcing everything on an internal enterprise network to run IPSEC so that the wireless subnet can be secure.
Using IPSEC on the wireless network only requires the wireless stations and a gateway to run IPSEC. The IPSEC gateway acts like a normal router to the rest of the network. You can even do transparent gatewaying based on proxy-arp.
Our laptops use 802.11b cards without WEP and 2 Linux machines with Prism2 based cards operating in HostAP mode. One AP handles the encryption and allows handoff to the other via proxy-arp depending on which AP has the link to a particular station on their own wired subnet. The primary AP acts as a router to the rest of the unencrypted wired lan. All the stations on the wireless lan are configured to drop all but the IPSEC traffic. This not only protects against spoofing and hijacking on the wireless lan but also gives strong encryption to the traffic.
After the pleasant experience I had with Freeswan on the wireless network I'm considering bringing IPSEC to the rest of the wired network.
Rotating the keys quickly will not solve the only problems with WEP. In general, encrypting stuff isn't enough. The receiver of encrypted data must insure that the data was not changed in route. Since the packet validator in WEP is CRC rather than something cryptographically strong, it is possible to perform replay attacks, or even worse, replay modified packets and have them be received as if they were legitimate. Even if it is not possible to decrypt packets, the ability to modify and reinject packets and have them be received creates some big problems.
Already implemented in Cisco's newest firmware, acu and drivers (both Linux and Windows). Since the old firmware wasn't even vulnevable to airsnort unless there were VERY determined hackers out there Cisco gear hasn't been vulnerable at all. With the new firmware they also implemented per packet hashing so spoof attacks are foiled.
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
The real problem with WEP isn't the weak method it uses to generate RC4 keys. I've seen with my own eyes many networks that don't even have encryption enabled.
:-)
The real problem is that encryption is:
A. Optional.
B. Difficult to set up.
WEP isn't close to being "wire equivalent" because wires are, by default, pretty secure. You don't need to manually enable 'no-public-hub-ports-on-external-walls' mode with a wired Ethernet.
A wire isn't just a way to get the bits from A to B - it also acts as a user interface for associating machines with networks. I bet you didn't think of the patch panel in the server room as a user interface, right? Actually, it's a pretty good user interface. It's much more intuitive than any GUI and very reliable (ok, so it's a little messy, but so is my desktop
Here's an idea for how WEP could have been much closer to 'wired equivalent':
When you set up the device on your machine it scans for available networks and shows a list. You choose one. It then tells you to press a key at the same time as pressing a button on the access point.
If you have physical access to the access point you can do it yourself. Otherwise you call the admin on the phone and after checking your identity (usually it's just a matter of recognizing your voice) the admin tells you to press the key '...now!'. That's it. You're on the network, with securely configured strong encryption.
This can be much more secure that it appears - the key is exchanged using Diffie-Hellman key exchange so eavesdropping is not possible. Man-in-the-middle attacks are difficult in a shared medium such as wireless where everyone hears everyone else: if the two participants are careful they can detect such attacks. To prevent attempts to 'take a ride' and join the network at the same time as another machine the access point will verify that there are no other attempts to join the network within a certain period before or after the time window for 'simultaneous' button presses (actually within plus or minus a few hundred milliseconds).
Now, what are the chances of some company actually implementing this?
Stop worrying about the risks of nuclear power and start worrying about the risks of not using nuclear power.