Is there a secure file system (or secure directory branch) for Linux?

Yes, you can use CFS, which works on several versions of UNIX as well as Linux. Send email to cfs@research.att.com to get a copy. Someone exported it, and it is also available from ftp://ftp.hacktic.nl/pub/crypto/CRYPTOapps/cfs.1.3.tar.gz There is also something called the "loop filesystem" for Linux. I haven't tried it and don't know how well it would integrate into the newer Linux kernels. ftp://tsx-11.mit.edu/pub/linux/BETA/loop -- Mark Henderson -- markh@wimsey.bc.ca, henderso@netcom.com, mch@squirrel.com PGP 1024/C58015E3 fingerprint=21 F6 AF 2B 6A 8A 0B E1 A1 2A 2A 06 4A D5 92 46 cryptography archive maintainer -- ftp://ftp.wimsey.com/pub/crypto ftp://ftp.netcom.com/pub/he/henderso/change-sun-hostid-1.5.0.tar.gz