Linux: SELinux policy configuration

# SPDX-FileCopyrightText: 2019 Greenbone AG
# Some text descriptions might be excerpted from (a) referenced
# source(s), and are Copyright (C) by the respective right holder(s).
#
# SPDX-License-Identifier: GPL-2.0-only

if(description)
{
  script_oid("1.3.6.1.4.1.25623.1.0.109741");
  script_version("2023-07-27T05:05:09+0000");
  script_tag(name:"last_modification", value:"2023-07-27 05:05:09 +0000 (Thu, 27 Jul 2023)");
  script_tag(name:"creation_date", value:"2019-01-16 08:27:48 +0100 (Wed, 16 Jan 2019)");
  script_tag(name:"cvss_base", value:"0.0");
  script_tag(name:"cvss_base_vector", value:"AV:L/AC:H/Au:S/C:N/I:N/A:N");
  script_tag(name:"qod", value:"97");

  script_name("Linux: SELinux policy configuration");

  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2019 Greenbone AG");
  script_family("Policy");
  script_dependencies("compliance_tests.nasl", "read_etc_selinux_config.nasl");
  script_mandatory_keys("Compliance/Launch");
  script_add_preference(name:"Policy configuration", type:"entry", value:"targeted", id:1);

  script_xref(name:"URL", value:"https://linux.die.net/man/8/selinux");

  script_tag(name:"summary", value:"Security Enhanced Linux (SELinux) use the Linux Security Modules
and provides Mandatory Access Control (MAC). A MAC kernel protects the system from malicious apps.
The SELinux policy is a set of rules that guide SELinux. The default targeted policy constraints
daemons and system software only.");

  exit(0);
}

include("policy_functions.inc");

cmd = "grep 'SELINUXTYPE' /etc/selinux/config";
title = "SELinux Policy";
solution = "Add 'SELINUX=[targeted|strict]' to /etc/selinux/conf";
test_type = "SSH_Cmd";
default = script_get_preference("Policy configuration", id:1);

if(get_kb_item("Policy/linux//etc/selinux/config/ERROR")){
  value = "Error";
  compliant = "incomplete";
  comment = "No SSH connection to host";
}else if(get_kb_item("Policy/linux//etc/selinux/config/ERROR")){
  value = "Error";
  compliant = "incomplete";
  comment = "Can not read /etc/selinux/config";
}else{
  content = get_kb_item("Policy/linux//etc/selinux/config/content");
  grep = egrep(string:content, pattern:"SELINUXTYPE\=");

  foreach line (split(grep)){
    if(line =~ "^\s*#")
      continue;

    match = eregmatch(string:chomp(line), pattern:"SELINUXTYPE=(.+)");
    if(match)
      value = match[1];
  }

  if(!value)
    value = "None";

  compliant = policy_setting_exact_match(value:value, set_point:default);
}

policy_reporting(result:value, default:default, compliant:compliant, fixtext:solution,
  type:test_type, test:cmd, info:comment);
policy_set_kbs(type:test_type, cmd:cmd, default:default, solution:solution, title:title,
  value:value, compliant:compliant);

exit(0);