Linux Firmware For Some 802.11b Access Points

drwho writes "This just unveiled at the BAWUG meeting tonight: Linux firmware for Access Points. Check this URL for more info. I haven't tried it yet but it looks great!" The upshot is that certain Access Points can be flashed with a stripped-down Linux system, which makes them more flexible than they'd be under the included firmware. There are even some screenshots of a modded access point booting up.

Comments

2.4.x

[tulare]

A quick thought - iptables on an access point? That I like. Think of all the possiblities...

Re:2.4.x

[autocracy]

Other quick thought - wouldn't that take up all the RAM while processing packets?

Re:2.4.x

[1010011010]

Another thought:

IPSec on the access point. Screw WEP!

Re:2.4.x

[tulare]

Not a bad point, actually. I don't imagine that you could run all the packets through some 500-line list of various netfilter errata. What I had in mind would be more like

1. iptables -A INPUT -s --source-mac [mac address of my allowed devices] -j ACCEPT
2. 
   iptables -P INPUT DROP
   iptables -t nat -A POSTROUTING -o [er, whatever the interface is called] -j MASQUERADE

Not neccessarily complete or accurate in terms of syntax, but you get the gist. Nothing requiring too much memory usage, but enough to ensure you can limit the use of the access point to trusted devices.

Re:2.4.x

[louissypher]

With the embedded processor that those access points have (16.4 BogoMips), forget IPSEC.

Re:2.4.x

[medcalf]

Just get an airport base station as your 802.11 access point, and then configure it to only accept connections from MACs you trust, using the appropriate box in the GUI. Oh, wait, that wouldn't be as much fun. It's too easy.

Sweet!

[jiminim]

So now I can run Seti on my AP?

Re:Sweet!

[mbyte]

> So now I can run Seti on my AP ?

yes. with 16 bogomips (according to screenshot ;)

firewall replacement

[47PHA60]

One thing that irks me to no end is that my home firewall is a noisy old Pentium 200 with disks and fans. I've been looking into embedded systems to do this, and the current access points I've seen are not effective firewalls at all; no logging, and they don't _reall_ block everything, even though they say they do. A small Linux kernel which does not need to be built up with support for PCI, two ethernet cards, disks and multiple filesystems might just do the trick.

Re:firewall replacement

[linzeal]

Underclock the proc and run it without a fan but get a big cheap socket 7 heatsink and get an rpm adjustable fan that will rev up and down according to a temparture probe included. I have an amd 500mhz underclocked to 375mhz without a fan that runs my firewall.

Re:firewall replacement

[Raptor CK]

How about this?

Two 10/100 ports, 1 serial port, one Mini-PCI slot, two PCMCIA/CardBus slots.
Granted, it's not out just yet, but you could make it handle wireless, inbound traffic, and two internal segments fairly easily.

The only problem is the dependence on CF. Logging isn't generally a good idea to media that can't handle excessive writes. While a Microdrive would fare better, it would also cost much more.

Re:firewall replacement

[Howie]

I use it as my MP3 server.

Without any disks?

Re:firewall replacement

[Etyenne]

syslogd -r

Slogan

[Hougaard]

I Like their slogan:

"All your base stations are belong to us"

.. Sense of humor :)

Mirror of Screenshots

[NewbieSpaz]

Here: http://kevindustries.com/screens.html

Re:Mirror of Screenshots

[Mignon]

Moderation Totals: Redundant=1, Informative=1, Total=2.

When I first saw this post, I thought - what a jackass moderator, marking this post as redundant. I mean, he's just trying to help. Then I realized that that's exactly what posting a mirror is: redundant and informative.

Finally

[mattyohe]

Multi-point to Multi-point works with this solution... its funny how going to linux solves my problems

Same Some Bucks?

[blitzrage]

I think that this is a cool idea. You can now upgrade and fix bugs, security holes etc.. yourself instead of having to wait for the vendor to do it (if they do it). Not to mention if you have a really old AP, maybe you can get it out and play around with Linux on it. This could allow you to take old AP's that people are pretty much throwing out, and recycle them. Might save you a few bucks. That'd be cool.

Hmm, security?

[RC514]

After the initial install with the SRAM card the access point can be upgraded over the network.

Does that mean the vendors of access points do not write protect the operating system on the hardware level? Or are future modifications only possible when the jumper remains in the upgrade position? If the jumper becomes meaningless after the upgrade, its implementation is a serious design flaw and an undetected rooting waiting to happen.

Re:802.11b ?

[Hougaard]

802.11b is wireless LAN. 11Mbit (With fallback to 5 and 2). A good reference is Nokia since they produce a complete setup.

Nokia Wireless LAN

I'm using (Nokia) 802.11b for all my home stuff now. No more cables running across the floor (This is really a wife pleaser :). Even my printers are connected on a miniport (To a jet direct box) and mounted on a little mobile table.

Hardware

[Cybersonic]

in case your curious, this works on access points using the Eumitcom WL11000SA-N boards...
( ref: http://opensource.instant802.com/hardware.php )
Tested: US Robotics 2450, SMC EZconnect 2652W

Time to buy an SMC for me :)

Re:How are they doing bridging?

[irregular_hero]

The "bridging code" is standard Linux bridging. I think what you're referring to is the "Host AP" or "Infrastructure" mode of the wireless card inside the AP.

If the card is based on the Prism chipset, there's already a Linux driver that will operate the card in Host AP mode by implementing some of the functions normally present in the access point's Infrastructure mode in user space. Other things are handled by the card.

For example, the card itself will handle time-dependent functions like beacon-sending. And it will handle hardware-dependent functions like WEP encrypt-decrypt (optionally). But the association table and all the rest of the functions are part of user space.

Incidentally, you don't need the Host AP driver for your Wireless card to operate a bridged network. Oddly enough, the bridge code in the Linux kernel functions just fine with a wireless card in Peer-to-Peer mode -- it is, after all, just another interface to the kernel itself. What you won't get in peer to peer is sophisticated association handling -- that means that the signal strength meter in your wireless tools won't work exactly right in most commercial packages.

Repeater?

[1010011010]

Could someone elaborate on the repeater functionality? Could I place unwired access points at regular distances, with only the one at the end wired to the regular network, and roam all down the chain with an 802.11b device (PDA for instance)?

Re:Repeater?

[dwhedon]

Exactly correct. The mesh formed between APs is an ethernet bridge. Stations associated with completely wireless APs (that is, no direct ethernet connection) will have their packets forwarded to the destination which may involve multiple wireless-wireless AP hops. The mesh is dynamic, APs can appear and disappear and stations can move between APs without loss of service.

David Kimdon
Instant802 Networks Inc.

You can build an AP on a PC:

[burntfungus]

You can build a Linux Access point on a PC or laptop, pehaps even a PDA:

http://people.ssh.com/jkm/Prism2/

Bridging software: http://bridge.sourceforge.net

Use serial port for modem backup?

[Fencepost]

One of the features that I like about the MultiTech router/switch I have is that a modem can be hung off the serial port and used as a backup connection. What would it take to do the same with this, and is there a getty out there that would support operating both ways (i.e. use a modem for dialout, but if a terminal was connected instead then allow login).

Try an old Laptop

[luiss]

Try getting hold of an old laptop. I got a 486 toshiba satelite for about $20, added two cheap PCMCIA ethernet cards, and loaded linux on it.

No fans (I think), battery backup, and LCD screen, nice...

There is a Linux on Laptops FAQ somewhere out there where you can check for compatability. Ebay is a good place to check for cheapo laptops. Just whatch out the the amount of RAM available. With no CD-ROM most of the old cheapo laptops can be a pain to get linux loaded, if your working from a distro whose imstall img can be over 8MB in size.

Re:Can I use this to turn my old notebook into an

[burntfungus]

Yes see: http://people.ssh.com/jkm/Prism2/

Lots o links on this subject: http://wireless.pasadena.net/links.php

Linux for the Airport

[ekalb]

There is a port of linux to the Apple Airport Base Station as well. However, it requires the use of a dhcp & tftp server, as well as the Java-based Airport admin tools.