HomePlug specification based powerline bridges are becoming increasingly popular. I've got myself two of them; the brand name is "ZEUS"; a strange brand that only seems to exist in Switzerland, and some people say it's actually ZyXEL (have a look at the guts). Whatever, according to the HomePlug alliance homepage (www.homeplug.org), there are only two manufacturers of powerline ICs at the moment: Intellon and Cogency Semiconductor. My bridges have the Intellon chipset (INT5130 integrated powerline MAC-PHY transceiver and INT1000 analog conversion IC). Intellon calls their implementation "PowerPacket".
Now, about the only thing that has to be configured with these is the encryption password, so your neighbor won't be able to sniff your data. A Windows program is provided for that purpose - you hook up the bridge directly to your PC, enter a 2-24 character password, and the password is saved into the bridge's EEPROM.
This is a bit of an inconvenience to non-Windows users, and even if you keep Windows boxes around, at least to me the software looks ugly. It keeps running strange daemons (WinPlcMan.exe, BridgeDeCor.exe, etc.) that use up to 100% CPU at times, and sometimes it's not possible to set the password without power cycling the bridge first (although that seems to be the fault of the bridge).
So I made an attempt at writing a program to set up the encryption key. I found some inofficial information on the web, and it agreed with what I learned from sniffing the communication between the PowerPacket setup software and the bridge.
I'm making the program available here for you to try; its status is currently somewhere in between an ugly hack and a simple use-once-and-throw-away tool. I have no idea if it works with other powerline bridges; although it should work with all Intellon-based ones. If you've had success with a particular product, please let me know!
Besides setting the encryption key, it can also capture and display powerline bridge management-related packets and request statistics from the bridge(s). All outgoing packets are sent as Ethernet broadcasts via the bpf device.
Current version: 0.2 – 06/08/2003 (download source)
Linux port by Enrik Berkhan: 0.2 – 08/03/2004 (download Linux source)
plconfig should work on most BSDs and Mac OS X (tested under FreeBSD 4.8 and Mac OS X 10.2)
Previous version: 0.1 – 10/12/2002 (download source)
Powerline Bridge config version 0.2 by Manuel Kasper <firstname.lastname@example.org> Usage: plconfig [-pqrh] [-b device] [-s key] interface -s key set network encryption key (plaintext password or 8 hex bytes preceded by 0x) -b device use device (default is /dev/bpf0) -p don't switch interface to promiscuous mode -r request parameters and statistics -q request Intellon-specific network statistics -h display this help If -s is not specified, plconfig will listen for management packets indefinitely (after requesting stats if -r is specified)
If you just want to set the password on all bridges that can be reached with an Ethernet broadcast, use:
plconfig -s mysecretpassword interface
...where "interface" is where your powerline bridge is attached (fxp0 or whatever). You can also specify the key directly as 8 hex bytes, e.g. 0x0123456789abcdef). If you specify a plaintext password, the key will be generated according to the HomePlug specification (compatible with the original Windows PowerPacket software).
If you start plconfig with no options (other than the interface), it will just capture and display all Intellon MAC management packets (ethertype = 0x887b).
The -b option can be used to specify an alternate bpf device (in case you're running dhclient/dhcpd/tcpdump at the same time, bpf0 may be occupied). -p can be used if you don't want plconfig to set promiscuous mode on the interface. You probably won't get any replies then (see notes). If you're using -s, promiscuous mode won't be enabled anyway (no need to read packets).
The -r and -q options (you can only specify one of them at a time) broadcast a request for statistics and then keep waiting for answers until you abort it (by pressing Ctrl-C). Sometimes the bridges don't return any answers, see the notes section.
Notes/Bugs/Caveats (read this!)