palfaiate / hntool

Hardening Tool for *nixes

HnTool

What is it?

HnTool is an open source (GPLv2) hardening tool for Unix. It scans your system for vulnerabilities or problems in configuration files allowing you to get a quick overview of the security status of your system.

To use HnTool download it and run: ::

# ./hntool

Supported systems

HnTool was already tested and is working on:

• Arch Linux
• CentOS
• Debian
• Fedora
• Gentoo
• Ubuntu

If you are using HnTool on a system that is not listed above, please, let us know.

How to install

To install HnTool run the following command, as root:

# python setup.py install --prefix /usr/ --root /

How to use

Run HnTool with:

# ./hntool

You can also see the hntool(1) manual by typing 'man hntool' at the command line or see the usage help:

$ hntool -h

Understanding the output

There are 5 types of results:

• OK : Means that the item checked is fine and that you do not need to worry

• INFO: Means that you should know the item status, but probably it is fine. A port opened, for example.

• LOW: Means that a security problem was found, but it does not provides a high risk for your system.

• MEDIUM: Things are getting worse and you should start to worry about these itens.

• HIGH: You have an important security hole/problem on your system and you should fix it NOW or run and save your life.

How can I help?

There are several ways that you can contribute and help HnTool's development. You can contribute with code, patchs, bugs and feature requests.

To report a bug or a feature request for HnTool, file a issue in our Google Code page: https://github.com/hdoria/HnTool

If you're reporting a bug, please give concrete examples of how and where the problem occurs.

If you've a patch (fixing a bug or a new HnTool module), then you can file an issue on Google Code too: http://code.google.com/p/hntool/issues/list

HnTool's source is available on:

https://github.com/hdoria/HnTool

How to create a module

This section documents the innards of HnTool and specifies how to create a new module.

The main HnTool program (hntool.py) runs a list of rules defined in __files__ and __services__.

• files : defines the rules which process simple files and configs.

• services : defines the rules which checks the security on services and daemons.

Once your module is finalized, remember to add it to the appropriate array (__files__ or __services__) defined in hntool/__init__.py

A sample HnTool module is like this (hntool/ssh.py):

import os
import HnTool.modules.util
from HnTool.modules.rule import Rule as MasterRule

class Rule(MasterRule):
def __init__(self, options):
    MasterRule.__init__(self, options)
    self.short_name="ssh"
    self.long_name="Checks security problems on sshd config file"
    self.type="config"
    self.required_files = ['/etc/ssh/sshd_config', '/etc/sshd_config']

def requires(self):
    return self.required_files

def analyze(self, options):
    check_results = self.check_results
    ssh_conf_file = self.required_files

    for sshd_conf in ssh_conf_file:
        if os.path.isfile(sshd_conf):
            # dict with all the lines
            lines = HnTool.modules.util.hntool_conf_parser(sshd_conf)

            # Checking if SSH is using the default port
            if 'Port' in lines:
                if int(lines['Port']) == 22:
                    check_results['low'].append('SSH is using the default port')
                else:
                    check_results['ok'].append('SSH is not using the default port')
            else:
                check_results['low'].append('SSH is using the default port')

    return check_results

Mostly, the code is self-explanatory. The following are the list of the attributes and methods that each HnTool module must have:

• self.short_name String containing a short name of the module. Usually,this is the same as the basename of the module file.

• self.long_name String containing a concise description of the module. This description is used when listing all the rules using hntool -l.

• analyze(self) Should return a list comprising in turn of five lists: ok, low, medium, high and info.

• self.type "files" or "config" for a module processing simple files and configs "services" for a module processing services and daemons