airo - Driver for the Aironet 802.11 ISA/PCI/PCMCIA 4500 & 4800 and Cisco 340

insmod airo.o [io=c i,j,...] [irq=c i,j,...] [basic_rate=c n] [rates=c i,j,...] [ssids=c i,j,...] [adhoc=c 1] [aux_bap=c 1] [auto_wep=c 1] [maxencrypt=c n]

This driver is for Cisco 340 and Aironet 4500 and 4800 ISA/PCI/PCMCIA cards and 2.0 or 2.2 kernels. Just for fun, I tested a 3500 for a total of 2 minutes and it seemed to work more or less. (The configuration information displayed in the Config file seemed a bit messed up.)

The card will create an ethX device for each wireless card. An entry for each device will be created under /proc/aironet/ethX with entries to view the status of the card and configure it.

In the /proc/aironet partition there will be a subdirectory for each aironet interface. In that subdirectory are four files: Status, Config, WepKey, and SSID.

Status

Most of the fields in the Status file are self describing. The Mode: field is a bitmask. Here is the description from the programmer's manual: Bit Meaning 0x0001 Configured 0x0002 MAC Enabled 0x0004 Receive Enabled 0x0010 In Sync 0x0020 Associated 0x8000 Error I'm not sure what the units are in the Signal: field.

Config

The Config file is mode up of fields separated by newlines. When setting the fields, they can occur in any order. If the values are in error, a sane default will be used. Note, there must be exactly one space between the colon and the value.

Mode:

can be "adhoc" or "ESS". Defaults to ESS.

NodeName:

Can be up to 16 characters in length

PowerMode:

Can be CAM (Constantly Awake Mode), PSP (Power Saving something...), PSPCAM (you guess...). CAM is default.

DataRates:

Must be separated by exactly 1 space. The units are 500 kps. So 2 is 1 mbs. There can be up to 8 rates specified. The basic rate set by setting the high bit (bit 7).

Channel:

Don't know anything about this except that you can set it...

XmitPower:

Transmit power in milliwatts.

WEP:

Can be open, encrypt, and shared, meaning no authentication, encrypted data only, shared key authentication and encryption. Note that when WEP is enabled the current cards (as of 9/9/99) do not allow data rates above 2 mbs.

Modulation:

Can be cck or mok. Sets the modulation type for speeds above 2mbs.

WepKey

This file allows all four wep keys to be set. The key is set by writing the index (0 == first key) of the key to be set, followed by a space, followed by the key as a string to the file. Each octet must be written in hexadecimal with leading zeros and separated by colons. For security reasons the key cannot be read from the card. Writing to this file sets both the permanent and temporary key. (Anyone have a need for being able to write them separately?) For example:

echo 0 12:04:78:9a:bc > /proc/aironet/eth0/WepKey When the file is read, it shows the length of the keys that are set and the index of the key that is set as the transmit key.

APList

Contains the list of MACs of the preferred APs. Each MAC address must be separated by a delimiter and each octet of the MAC should be separated by a delimiter and each octet should have two digits. 01:02:03:04:05:06 and 01-02-03:04:05,06 are valid. 1:2:3:4:5:6 is not. I usually separate the MACs by linefeeds but any character works.

SSID

The SSID file has the list of usable SSIDs. If the list is empty, it will associate with any access point that it can find. The SSIDs are separated by line feeds. This file may also be written to to change the list.

Stats/StatsDelta

Basically a dump of all the statistics of the card. The source has provisions for all the statistics even though by default a lot of them are turned off. Stats give the statistics from the time the card was powered up. StatsDelta gives the statistics from the time the statistics were last reset. The statistics are reset by opening the StatsDelta file for writing.

io=i,j,...

Specifies the set of ioports used by the driver. This is only used for ISA cards. The irq to be used will match the irq in the same position in the irq list. So basically ioport at index i will be used with the irq at index i.

irq=i,j,...

Specifies the set of interrupts are used by the driver.

rates=i,j,...

A comma separated list of rates. There are up to 8 of them. They are specified in 512 kps units.

basic_rate=n

Sets the basic rate of the card. Same units as the rates. (It must be one of the rates.)

ssids=i,j,k

A comma separated list of ssids. There can be up to 3. They are a maximum of 32 characters.

maxencrypt=n

Sets the maximum speed of the card when doing encryption. If zero (the default), it is not used. Units are in 512kbs. Older cards could only do 2mbs (n=4) when doing encryption, even though they could do 11 mbs without encryption.

auto_wep=n

Turns on logic to cycle through the different WEP settings until the card is able to associate. It will also cycle through the wep keys. n is the number of keys to cycle through. Note, it only cycles through the keys for shared mode. When encrypt is tried, it will use the permanent key index. (See WepKey.)

aux_bap=1

Enables logic that gets around bus timing problems on older cards with some boards. The timing problem manifests itself when receiving packets bigger than 70 bytes.

When used with PCMCIA cards, it must be used with the airo_cs module.

Benjamin C. Reed - breed@almaden.ibm.com

airo_cs(4), cardmgr(8), pcmcia(5), insmod(1),