xref: /freebsd/share/examples/flua/libjail.lua (revision 911f0260390e18cf85f3dbf2c719b593efdc1e3c)
1#!/usr/libexec/flua
2--[[
3/*-
4 * SPDX-License-Identifier: BSD-2-Clause
5 *
6 * Copyright (c) 2020, Ryan Moeller <freqlabs@FreeBSD.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD$
30 */
31]]--
32
33jail = require("jail")
34ucl = require("ucl")
35
36name = "demo"
37
38local has_demo = false
39
40-- Make sure we don't have a demo jail to start with; "jid" and "name" are
41-- always present.
42for jparams in jail.list() do
43    if jparams["name"] == name then
44        has_demo = true
45        break
46    end
47end
48
49if not has_demo then
50    -- Create a persistent jail named "demo" with all other parameters default.
51    jid, err = jail.setparams(name, {persist = "true"}, jail.CREATE)
52    if not jid then
53        error(err)
54    end
55end
56
57-- Get a list of all known jail parameter names.
58allparams = jail.allparams()
59
60-- Get all the parameters of the jail we created.
61jid, res = jail.getparams(name, allparams)
62if not jid then
63    error(res)
64end
65
66-- Display the jail's parameters as a pretty-printed JSON object.
67print(ucl.to_json(res))
68
69-- Confirm that we still have it for now.
70has_demo = false
71for jparams in jail.list() do
72    if jparams["name"] == name then
73        has_demo = true
74        break
75    end
76end
77
78if not has_demo then
79    print("demo does not exist")
80end
81
82-- Update the "persist" parameter to "false" to remove the jail.
83jid, err = jail.setparams(name, {persist = "false"}, jail.UPDATE)
84if not jid then
85    error(err)
86end
87
88-- Verify that the jail is no longer on the system.
89local is_persistent = false
90has_demo = false
91for jparams in jail.list({"persist"}) do
92    if jparams["name"] == name then
93        has_demo = true
94        jid = jparams["jid"]
95        is_persistent = jparams["persist"] ~= "false"
96    end
97end
98
99-- In fact, it does remain until this process ends -- c'est la vie.
100if has_demo then
101    io.write("demo still exists, jid " .. jid .. ", ")
102    if is_persistent then
103        io.write("persistent\n")
104    else
105        io.write("not persistent\n")
106    end
107end
108