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ChrootDirectory
Specifies a path to chroot(2) to after authentication. This
path, and all its components, must be root-owned directories that
are not writable by any other user or group.
The path may contain the following tokens that are expanded at
runtime once the connecting user has been authenticated: %% is
replaced by a literal ’%’, %h is replaced by the home directory
of the user being authenticated, and %u is replaced by the user-
name of that user.
The ChrootDirectory must contain the necessary files and directo-
ries to support the users’ session. For an interactive session
this requires at least a shell, typically sh(1), and basic /dev
nodes such as null(4), zero(4), stdin(4), stdout(4), stderr(4),
arandom(4) and tty(4) devices. For file transfer sessions using
“sftp”, no additional configuration of the environment is neces-
sary if the in-process sftp server is used (see Subsystem for
details).
The default is not to chroot(2).