freebsd-skq/lib/flua/libjail/jail.3lua

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.Dd October 24, 2020
.Dt JAIL 3lua
.Os
.Sh NAME
.Nm getid ,
.Nm getname ,
.Nm allparams ,
.Nm getparams ,
.Nm setparams ,
.Nm CREATE ,
.Nm UPDATE ,
.Nm ATTACH ,
.Nm DYING
.Nd Lua binding to
.Xr jail 3
.Sh SYNOPSIS
.Bd -literal
local jail = require('jail')
.Ed
.Pp
.Bl -tag -width XXXX -compact
.It Dv jid, err = jail.getid(name)
.It Dv name, err = jail.getname(jid)
.It Dv params, err = jail.allparams()
.It Dv jid, res = jail.getparams(jid|name, params [, flags ] )
.It Dv jid, err = jail.setparams(jid|name, params, flags )
.It Dv jail.CREATE
.It Dv jail.UPDATE
.It Dv jail.ATTACH
.It Dv jail.DYING
.El
.Sh DESCRIPTION
The
.Nm jail
module is a binding to the
.Xr jail 3
library.
It provides a string-oriented interface for the
.Xr jail_get 2
and
.Xr jail_set 2
system calls.
.Bl -tag -width XXXX
.It Dv jid, err = jail.getid(name)
Get the jail identifier
.Pq jid
as an integer.
.Fa name
is the name of a jail or a jid in the form of a string.
.It Dv name, err = jail.getname(jid)
Get the name of a jail as a string for the given
.Fa jid
.Pq an integer .
.It Dv params, err = jail.allparams()
Get a list of all supported parameter names
.Pq as strings .
See
.Xr jail 8
for descriptions of the core jail parameters.
.It Dv jid, res = jail.getparams(jid|name, params [, flags ] )
Get a table of the requested parameters for the given jail.
.Nm jid|name
can either be the jid as an integer or the jid or name as a string.
.Nm params
is a list of parameter names.
.Nm flags
is an optional integer representing the flag bits to apply for the operation.
See the list of flags below.
Only the
.Dv DYING
flag is valid to set.
.It Dv jid, err = jail.setparams(jid|name, params [, flags ] )
Set parameters for a given jail.
This is used to create, update, attach to, or destroy a jail.
.Nm jid|name
can either be the jid as an integer or the jid or name as a string.
.Nm params
is a table of parameters to apply to the jail, where each key in the table
is a parameter name as a string and each value is a string that will be
converted to the internal value type by
.Xr jailparam_import 3 .
.Nm flags
is an optional integer representing the flag bits to apply for the operation.
See the list of flags below.
.El
.Pp
The
.Nm flags
arguments are an integer bitwise-or combination of one or more of the following
flags:
.Bl -tag -width XXXX
.It Dv jail.CREATE
Used with
.Fn setparams
to create a new jail.
The jail must not already exist, unless combined with
.Dv UPDATE .
.It Dv jail.UPDATE
Used with
.Fn setparams
to modify an existing jail.
The jail must already exist, unless combined with
.Dv CREATE .
.It Dv jail.ATTACH
Used with
.Fn setparams
in combination with
.Dv CREATE
or
.Dv UPDATE
to attach the current process to a jail.
.It Dv jail.DYING
Allow operating on a jail that is in the process of being removed.
.El
.Sh RETURN VALUES
The
.Fn getid
and
.Fn setparams
functions return a jail identifier integer on success, or
.Dv nil
and an error message string if an error occurred.
.Pp
The
.Fn getname
function returns a jail name string on success, or
.Dv nil
and an error message string if an error occurred.
.Pp
The
.Fn allparams
function returns a list of parameter name strings on success, or
.Dv nil
and an error message string if an error occurred.
.Pp
The
.Fn getparams
function returns a jail identifier integer and a table of jail parameters
with parameter name strings as keys and strings for values on success, or
.Dv nil
and an error message string if an error occurred.
.Sh EXAMPLES
Set the hostname of jail
.Dq foo
to
.Dq foo.bar :
.Bd -literal -offset indent
local jail = require('jail')

jid, err = jail.setparams("foo", {["host.hostname"]="foo.bar"},
    jail.UPDATE)
if not jid then
    error(err)
end
.Ed
.Pp
Retrieve the hostname of jail
.Dq foo :
.Bd -literal -offset indent
local jail = require('jail')

jid, res = jail.getparams("foo", {"host.hostname"})
if not jid then
    error(res)
end
print(res["host.hostname"])
.Ed
.Sh SEE ALSO
.Xr jail 2 ,
.Xr jail 3 ,
.Xr jail 8
.Sh HISTORY
The
.Nm jail
Lua module for flua first appeared in
.Fx 13.0 .
.Sh AUTHORS
.An Ryan Moeller ,
with inspiration from
.Nx
gpio(3lua), by
.An Mark Balmer .