I just installed Ubuntu 12.04 to dual boot with OS X Lion on my MacBook 4,1 (early 2008). Wireless doesn't work. Ubuntu knows--get the Broadcom driver, right? Sure, but the problem is I'm tethered to an iPhone and thus have no access to a wired connection to download it in Ubuntu! So my question is how do I download the driver on OS X and install it in Ubuntu?
UPDATE 1: I followed the instructions here, had problems the first time I tried it (gave me a big screen full of text and had to restart), and now get the text "Invalid ROM contents" before the Ubuntu desktop loads. Wireless still does not work.
UPDATE 2: I just tried following instructions here and here. Didn't work! For some reason it can't get anything from the install media. It seems like certain files are missing or don't work and certain options are just unavailable. With Broadcom's own instructions, I get "Operation not permitted" on the Terminal commands under step 2 of the instructions for a fresh installation.
There has to be an answer!
UPDATE 3: I am able to connect to the internet briefly with Ubuntu using Bluetooth to tether. The connection is intermittent, only staying on for a few seconds before disconnecting and connecting again. I can visit web pages but I can't say it would work on package downloads. I tried installing the Broadcom drivers through "Additional Hardware" but got the same error message I got before about not being able to install it.
UPDATE 4: The output of
lspci -nn | grep -i network is
02:00.0 Network controller : Broadcom Corporation BCM4321 802.11a/b/g/n [14e4:4328] (rev 03)
sudo modprobe b43 doesn't seem to do anything. I do still have the /lib/firmware/b43 folder and contents as explained in UPDATE 1--it gave me some trouble.