Ubuntu manuals

Provided by: sfs-common_0.8-0+pre20060720.1-1.1_i386

NAME

        SFS - Self Certifying Filesystem
 

DOCUMENTATION

        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.
 

DESCRIPTION

        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:
 
        http://www.fs.net/
        SFS mounts directories from fileservers under a directory in the form:
 
        /sfs/@Location,HostID
 
        Location is either ip address or DNS hostname of the server.
 
        HostID is a collision-resistant cryptographic hash of the file server’s
        public key.
        Client side operation of SFS consists of following programs:
 
        sfscd
          creates and serves /sfs directory on client machine. Also starts nfs‐
          mounter and sfsrwcd as needed.
 
        nfsmounter
          mounts and unmounts NFS filesystems as kernel NFS client accesses
          them.
 
        sfsrwcd
          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:
 
        sfsagent
          handles authentication as user moves to new filesystems.  It also can
          fetch new HostIDs and perform revocation checks on them.
 
        sfskey
          manages user and server keys and is used to configure sfsagent for
          different situations.
 
        rex
          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:
 
        sfssd
          handles incoming connections and spawns sfsrwcd and sfsrwcd as
          needed.
 
        sfsrwcd
          is a daemon that implements normal read/write filesystem protocol and
          talks to local NFS server.
 
        sfsauthd
          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.
 
        rexd
          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.
 
        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:
 
        ssu
          allows an unprivileged user to become root on the local machine with‐
          out changing his SFS credentials.
 
        rpcc
          an RPC compiler for RFC1832-format XDR files.  Used by other systems
          that link against the SFS libraries.
 
        funmount
          forcibly unmounts a file system, doing as little else as possible.
          May be of use when cleaning up a system after a crash.
 
        dirsearch
          can be used with sfskey certprog command to configure certification
          paths--lists of directories in which to look for symbolic links to
          HostIDs.
        sfskey(1), nfs(5), info(1), sfsagent(1)
 

NOTES

        Solid NFSv3 support is required from kernel and supporting utilities.
 

CAVEATS

        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.
 

AUTHOR

        SFS was written by the SFS development team, sfsdev@redlab.lcs.mit.edu.
        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.