[chef] Re: RE: Re: Chef's sudo cookbook and the passwordless access

[Lamont Granquist < >]

Title: RE: [chef] Re: Chef's sudo cookbook and the passwordless access

On 3/14/15 10:24 PM, Kevin Keane Subscription wrote:

" type="cite">

I don't think using the sudoers.d directory is a good idea, because it is a security problem. There are two specific issues with it.

First, a hacker may be able to add his own file to the sudoers.d directory. That would be a classic injection/privilege escalation attack. Granted, it's a bit more difficult because /etc/sudoers.d has permissions restricting it to root, but since it is also managed by chef, there can still be ways for a non-root user to insert a file into this directory.

If an attacker can create a file in /etc/sudoers.d with arbitrary content they can also create a file in /etc/cron.d with arbitrary content and run a command as root via cron to give them a backdoor.

" type="cite">

The bigger issue is that there is no good way to automatically clean up obsolete entries from the sudoers.d directory; you may end up giving sudo access to people who should no longer have it.

That's a solvable problem.  The zap cookbook is one way.

" type="cite">

From a security standpoint, it is dramatically better to only have a sudoers file and no include statement, especially not an include of a directory.

Kevin Keane

The NetTech

http://www.4nettech.com

Our values: Privacy, Liberty, Justice

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-----Original message-----
From: tayworm .  ">< >
Sent: Friday 13th March 2015 13:03
To: ">
Subject: [chef] Re: Chef's sudo cookbook and the passwordless access

A better way to use the cookbook would be to create files in sudoers.d for each entry. https://github.com/opscode-cookbooks/sudo#lwrp

On Fri, Mar 13, 2015 at 8:52 AM, Jimmy Huang < " target="_blank" title="This external link will open in a new window"> > wrote:

Hi,

I am trying to figure out how best to use the sudo cookbook.  My cookbook is called masterwrap.

Berkesfile:

source "https://supermarket.chef.io"

metadata

masterwrap/metadata.rb:

name             'masterwrap'
maintainer       'The Authors'
maintainer_email '
 
 " target="_blank" title="This external link will open in a new window">
 '
license          'all_rights'
description      'Installs/Configures masterwrap'
long_description 'Installs/Configures masterwrap'
version          '0.1.0'

depends 'git', '~> 4.1.0'
depends 'sudo', '~> 2.7.1'
depends 'users', '~> 1.8.0'

masterwrap/recipes/default.rb:

#
# Cookbook Name:: masterwrap
# Recipe:: default
#
# Copyright (c) 2015 The Authors, All Rights Reserved.

include_recipe 'git'
include_recipe 'masterwrap::users'

masterwrap/recipes/users.rb:

#
# Cookbook Name:: masterwrap
# Recipe:: users
#
# Copyright (c) 2015 The Authors, All Rights Reserved.

include_recipe 'sudo'
include_recipe 'users'

%w(deploy sysadmin).each do |group|
  users_manage group do
    data_bag 'users'
    action [ :remove, :create ]
  end
end

sudo 'sysadmin' do
  group '%sysadmin'
  nopasswd false
end

If I converge at this point, my vagrant user would stop having passwordless sudo access.  To make sure that does not happen, I have the following masterwrap/.kitchen.yml file:

---
driver:
  name: vagrant

provisioner:
  name: chef_zero

platforms:
  - name: ubuntu1404
    driver:
      box: ubuntu/trusty64
      box_url: ubuntu/trusty64
    attributes:
      authorization:
        sudo:
          users: ['vagrant']
          passwordless: true
          include_sudoers_d: true

suites:
  - name: default
    data_bags_path: 'test/fixtures/data_bags'
    run_list:
      - recipe[masterwrap::default]
    attributes:

The problem is that I DO want a password prompt for my sudo access for non-vagrant users, but I am not sure how to go about achieving that.  Here is my current /etc/sudoers file after the converge:

# This file is managed by Chef.

# Do NOT modify this file directly.

Defaults      !lecture,tty_tickets,!fqdn

# User privilege specification

root          ALL=(ALL) ALL

vagrant ALL=(ALL) NOPASSWD:ALL

# Members of the group 'sysadmin' may gain root privileges

%sysadmin ALL=(ALL) NOPASSWD:ALL

===

Given the node's structure, I think the sudo cookbook assumes everyone who is granted sudo access via the cookbook will want the same setting for passwordless, which is not the desired outcome in my case.  Is there a way around this assumption or a better way for me to use the sudo cookbook?  Thank you for your help.

Sincerely,

Jimmy