Provided by: ecryptfs-utils_83-0ubuntu3_i386 bug

NAME

       eCryptfs - an enterprise-class cryptographic filesystem for linux

SYNOPSIS

       mount -t ecryptfs [SRC DIR] [DST DIR] -o [OPTIONS]

DESCRIPTION

       eCryptfs  is  a  POSIX-compliant enterprise-class stacked cryptographic
       filesystem  for  Linux.  It  is  derived  from  Erez  Zadok’s  Cryptfs,
       implemented   through   the   FiST  framework  for  generating  stacked
       filesystems.  eCryptfs  extends  Cryptfs  to   provide   advanced   key
       management and policy features.  eCryptfs stores cryptographic metadata
       in the header of each file written, so  that  encrypted  files  can  be
       copied between hosts; the file will be decryptable with the proper key,
       and there is no need to keep track of any additional information  aside
       from what is already in the encrypted file itself. Think of eCryptfs as
       a sort of "gnupgfs."

OPTIONS

       KERNEL OPTIONS

            Parameters that apply to the eCryptfs kernel module.

       ecryptfs_sig=(fekek_sig)
              Specify the signature of the mount  wide  authentication  token.
              The  authentication  token  must be in the kernel keyring before
              the mount is performed. ecryptfs-manager or the  eCryptfs  mount
              helper can be used to construct the authentication token and add
              it to the keyring prior to mounting.

       ecryptfs_fnek_sig=(fnek_sig)
              Specify the signature of the  mount  wide  authentication  token
              used  for  filename  crypto.  The  authentication must be in the
              kernel keyring before mounting.

       ecryptfs_cipher=(cipher)
              Specify the symmetric cipher to be used on a per file basis

       ecryptfs_key_bytes=(key_bytes)
              Specify the keysize to be used with the selected cipher. If  the
              cipher  only  has  one  keysize  the keysize does not need to be
              specified.

       ecryptfs_passthrough
              Allows for non-eCryptfs files to be read and written from within
              an eCryptfs mount. This option is turned off by default.

       no_sig_cache
              Do  not  check the mount key signature against the values in the
              user’s ~/.ecryptfs/sig-cache.txt file. This is useful  for  such
              things  as  non-interactive  setup  scripts,  so  that the mount
              helper does not stop and prompt the user in the event  that  the
              key sig is not in the cache.

       ecryptfs_encrypted_view
              This  option  provides  a  unified  encrypted file format of the
              eCryptfs files in the lower mount point.  Currently, it is  only
              useful if the lower mount point contains files with the metadata
              stored in the extended attribute.  Upon a file read in the upper
              mount point, the encrypted version of the file will be presented
              with the metadata in the  file  header  instead  of  the  xattr.
              Files  cannot be opened for writing when this option is enabled.

       ecryptfs_xattr
              Store the metadata in the extended attribute of the lower  files
              rather than the header region of the lower files.

       verbose
              Log  ecryptfs  information  to  /var/log/messages.   Do  not run
              eCryptfs in verbose-mode unless you are doing so  for  the  sole
              purpose  of development, since secret values will be written out
              to the system log in that case.

       MOUNT HELPER OPTIONS

              Parameters that apply to the eCryptfs mount helper.

       key=(keytype):[KEY MODULE OPTIONS]
              Specify the type of key to be used when mounting eCryptfs.

       ecryptfs_enable_filename_crypto=(y/N)
              Specify whether filename encryption should be enabled.  If  not,
              the  mount  helper  will  not  prompt  the user for the filename
              encryption key signature.

       verbosity=0/1
              If verbosity=1, the mount helper will ask you for missing values
              (default).   Otherwise,  if  verbosity=0,  it  will  not ask for
              missing values and will fail if required values are omitted.

       KEY MODULE OPTIONS

              Parameters that apply to individual key modules have  the  alias
              for  the  key  module  in  the prefix of the parameter name. Key
              modules are pluggable, and which key modules  are  available  on
              any  given  system  is  dependent  upon  whatever  happens to be
              installed in /usr/lib*/ecryptfs/. By default, this includes,  at
              a minimum, "passphrase" and "openssl."

       passphrase_passwd=(passphrase)
              The  actual  password is password. Since the password is visible
              to utilities (like ps under Unix) this form should only be  used
              where security is not important.

       passphrase_passwd_file=(filename)
              The    password   should   be   specified   in   a   file   with
              passwd=(passphrase). It is highly reccomended that the  file  be
              stored on a secure medium such as a personal usb key.

       passphrase_passwd_fd=(file descriptor)
              The password is specified through the specified file descriptor.

       passphrase_salt=(hex value)
              The salt should be specified as a 16 digit hex value.

       openssl_keyfile=(filename)
              The filename should be the filename of a file containing an  RSA
              SSL key.

       openssl_passwd_file=(filename)
              The    password   should   be   specified   in   a   file   with
              openssl_passwd=(openssl-password). It is highly reccomended that
              the  file  be  stored  on a secure medium such as a personal usb
              key.

       openssl_passwd_fd=(file descriptor)
              The password is specified through the specified file descriptor.

       openssl_passwd=(password)
              The  password  can  be  specified on the command line. Since the
              password  is  visible  in  the  process  list,  it   is   highly
              recommended to use this option only for testing purposes.

EXAMPLE

       The  following  command  will  layover mount eCryptfs on /secret with a
       passphrase contained in a  file  stored  on  secure  media  mounted  at
       /mnt/usb/.

       mount                  -t                  ecryptfs                  -o
       key=passphrase:passphrase_passwd_file=/mnt/usb/file.txt /secret /secret

       Where  file.txt contains the contents "passphrase_passwd=[passphrase]".

SEE ALSO

       mount(8)

       /usr/share/doc/ecryptfs-utils/ecryptfs-faq.html

       http://launchpad.net/ecryptfs/

NOTES

       Do not run eCryptfs in verbose-mode unless you are  doing  so  for  the
       sole purpose of development, since secret values will be written out to
       the system log in that case. Make  certain  that  your  eCryptfs  mount
       covers  all locations where your applications may write sensitive data.
       In addition, use dm-crypt to encrypt your swap space with a random  key
       on boot, or see ecryptfs-setup-swap(1).

       Passphrases have a maximum length of 64 characters.

BUGS

       Please  post  bug reports to the eCryptfs bug tracker on Launchpad.net:
       https://bugs.launchpad.net/ecryptfs/+filebug.

       For  kernel   bugs,   please   follow   the   procedure   detailed   in
       Documentation/oops-tracing.txt to help us figure out what is happening.

AUTHOR

       This    manpage     was     (re-)written     by     Dustin     Kirkland
       <kirkland@canonical.com>  for  Ubuntu  systems  (but  may  be  used  by
       others).  Permission is granted to copy, distribute and/or modify  this
       document  under  the terms of the GNU General Public License, Version 2
       or any later version published by the Free Software Foundation.

       On Debian systems, the complete text of the GNU General Public  License
       can be found in /usr/share/common-licenses/GPL.