Provided by: sfs-common_0.8-0+pre20060720.1-1.1_i386
SFS - Self Certifying Filesystem
This manpage was written as short description and as pointer to more
complete documentation. Up to date documentation can be found as Info-
pages of SFS. You can access the Info pages with command "info sfs".
An HTML version of the info pages may also be available on your system
in /usr/local/lib/sfs/sfs.html or /usr/lib/sfs/sfs.html.
SFS is a secure, global network filesystem with completedly decentral‐
ized control. It takes NFS shares exported from localhost and trans‐
ports them securely to other hosts; NFS services do not need to be
exposed to network.
SFS features key management and authorization separated from filesystem
with key revokation separated from key distribution.
More information and new versions can be found on the SFS website:
SFS mounts directories from fileservers under a directory in the form:
Location is either ip address or DNS hostname of the server.
HostID is a collision-resistant cryptographic hash of the file server’s
Client side operation of SFS consists of following programs:
creates and serves /sfs directory on client machine. Also starts nfs‐
mounter and sfsrwcd as needed.
mounts and unmounts NFS filesystems as kernel NFS client accesses
is a daemon that implements normal read/write filesystem protocol.
It acts as a NFS server to local NFS client.
On client machine user normally uses the following prog- rams:
handles authentication as user moves to new filesystems. It also can
fetch new HostIDs and perform revocation checks on them.
manages user and server keys and is used to configure sfsagent for
a remote login program, similar in spirit to SSH, that uses SFS’s key
management and authentication mechanisms, and can forward a user’s
sfsagent to remote machines.
Server side consists of following programs:
handles incoming connections and spawns sfsrwcd and sfsrwcd as
is a daemon that implements normal read/write filesystem protocol and
talks to local NFS server.
handles user authentication. It communicates directly with sfsrwsd to
authenticate users of the file system. It also accepts connections
over the network from sfskey to let users download their private keys
or change their public keys.
remote login server that performs key exchange with remote rex
clients and does authorization checking of remote users before allow‐
ing them to spawn or connect to proxy.
server-side of the rex remote login utility, which clients spawn and
connect to through the privileged rexd server. There is typically
one instance of proxy per user logged into a machine (regardless of
how many times the user is logged in), running with the permissions
of the user.
There are few small programs to help with misc tasks:
allows an unprivileged user to become root on the local machine with‐
out changing his SFS credentials.
an RPC compiler for RFC1832-format XDR files. Used by other systems
that link against the SFS libraries.
forcibly unmounts a file system, doing as little else as possible.
May be of use when cleaning up a system after a crash.
can be used with sfskey certprog command to configure certification
paths--lists of directories in which to look for symbolic links to
sfskey(1), nfs(5), info(1), sfsagent(1)
Solid NFSv3 support is required from kernel and supporting utilities.
You really do not want to kill -9 nfsmounter, as it is responsible for
cleaning up and unmounting filesystems on the client side, if sfscd has
died or something else happened.
SFS was written by the SFS development team, firstname.lastname@example.org.
This manpage was originally written by Jaakko Niemi for sfs packaging
in Debian/GNU Operating System. It has since been edited by the SFS
development team and included with the SFS distribution.