What key length is used in blowfish hard disk encryption?

[Stefan Ohletz <dabifml_(_at_)_gmx_(_dot_)_net>]

Reading the manual pages of vnconfig(8) and blowfish(3), I was asking 
myself how many characters are used for the encryption key of virtual 
disk devices at all. Looking at the source code of vnconfig, it looks to 
me as if the maximum number of characters which can be entered at the 
password prompt is 128, but examining the source code of 
sys/crypto/blf.{h,c} more closely, I'm getting the impression that only 
56 bytes (the maximum key length of the blowfish algorithm) are really 
utilized. Please, is my observation correct?

(Since I'd like to use diceware[1] passphrases with vnconfig, if it *is* 
correct, I'd have to write my own function for getting the passphrase 
from the terminal and translate it into an appropriate blowfish key. 
That's the reason why I'm asking.)

Regards, Stefan

[1] http://www.diceware.com