e4crypt(8) — Linux manual page


E4CRYPT(8)                 System Manager's Manual                E4CRYPT(8)

NAME         top

       e4crypt - ext4 filesystem encryption utility

SYNOPSIS         top

       e4crypt add_key -S [ -k keyring ] [-v] [-q] [ -p pad ] [ path ... ]
       e4crypt new_session
       e4crypt get_policy path ...
       e4crypt set_policy [ -p pad ] policy path ...

DESCRIPTION         top

       e4crypt performs encryption management for ext4 file systems.

COMMANDS         top

       e4crypt add_key [-vq] [-S salt ] [-k keyring ] [ -p pad ] [ path ...
              Prompts the user for a passphrase and inserts it into the
              specified keyring.  If no keyring is specified, e4crypt will
              use the session keyring if it exists or the user session
              keyring if it does not.

              The salt argument is interpreted in a number of different
              ways, depending on how its prefix value.  If the first two
              characters are "s:", then the rest of the argument will be
              used as an text string and used as the salt value.  If the
              first two characters are "0x", then the rest of the argument
              will be parsed as a hex string as used as the salt.  If the
              first characters are "f:" then the rest of the argument will
              be interpreted as a filename from which the salt value will be
              read.  If the string begins with a '/' character, it will
              similarly be treated as filename.  Finally, if the salt
              argument can be parsed as a valid UUID, then the UUID value
              will be used as a salt value.

              The keyring argument specifies the keyring to which the key
              should be added.

              The pad value specifies the number of bytes of padding will be
              added to directory names for obfuscation purposes.  Valid pad
              values are 4, 8, 16, and 32.

              If one or more directory paths are specified, e4crypt will try
              to set the policy of those directories to use the key just
              added by the add_key command.  If a salt was explicitly
              specified, then it will be used to derive the encryption key
              of those directories.  Otherwise a directory-specific default
              salt will be used.

       e4crypt get_policy path ...
              Print the policy for the directories specified on the command

       e4crypt new_session
              Give the invoking process (typically a shell) a new session
              keyring, discarding its old session keyring.

       e4crypt set_policy [ -p pad ] policy path ...
              Sets the policy for the directories specified on the command
              line.  All directories must be empty to set the policy; if the
              directory already has a policy established, e4crypt will
              validate that the policy matches what was specified.  A policy
              is an encryption key identifier consisting of 16 hexadecimal

AUTHOR         top

       Written by Michael Halcrow <mhalcrow@google.com>, Ildar Muslukhov
       <muslukhovi@gmail.com>, and Theodore Ts'o <tytso@mit.edu>

SEE ALSO         top

       keyctl(1), mke2fs(8), mount(8).

COLOPHON         top

       This page is part of the e2fsprogs (utilities for ext2/3/4
       filesystems) project.  Information about the project can be found at
       ⟨http://e2fsprogs.sourceforge.net/⟩.  It is not known how to report
       bugs for this man page; if you know, please send a mail to
       man-pages@man7.org.  This page was obtained from the project's up‐
       stream Git repository
       ⟨git://git.kernel.org/pub/scm/fs/ext2/e2fsprogs.git⟩ on 2020-11-01.
       (At that time, the date of the most recent commit that was found in
       the repository was 2020-10-01.)  If you discover any rendering prob‐
       lems in this HTML version of the page, or you believe there is a bet‐
       ter or more up-to-date source for the page, or you have corrections
       or improvements to the information in this COLOPHON (which is not
       part of the original manual page), send a mail to man-pages@man7.org

E2fsprogs version 1.46-WIP       March 2020                       E4CRYPT(8)