9603b8a04e
This fixes a few minor rst format issues like: * nested lists which were shown as blockquote * code-blocks which were show as blockquote * underlining of titles which didn't match * missing backslash escaping in parsed-literal Change-Id: I9b0934112f7f26775af52b6fc7de9fd29b215998
162 lines
7.4 KiB
ReStructuredText
162 lines
7.4 KiB
ReStructuredText
====================
|
||
Appendix D: Security
|
||
====================
|
||
|
||
Security is one of the top priorities within OpenStack-Ansible (OSA), and many
|
||
security enhancements for OpenStack clouds are available in deployments by
|
||
default. This appendix provides a detailed overview of the most important
|
||
security enhancements.
|
||
|
||
For more information about configuring security, see
|
||
:deploy_guide:`Appendix G <app-advanced-config-options.html>`.
|
||
|
||
.. note::
|
||
|
||
Every deployer has different security requirements.
|
||
The `OpenStack Security Guide`_ has instructions and advice on how to
|
||
operate and consume an OpenStack cloud by using the most secure methods.
|
||
|
||
Encrypted communication
|
||
~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
Any OpenStack cloud has sensitive information transmitted between
|
||
services, including user credentials, service credentials or
|
||
information about resources being created. Encrypting this traffic is critical
|
||
in environments where the network cannot be trusted. (For more information
|
||
about securing the network, see the :ref:`least-access-openstack-services`
|
||
section.)
|
||
|
||
Many of the services deployed with OpenStack-Ansible are encrypted by default
|
||
or offer encryption as an option. The playbooks generate self-signed
|
||
certificates by default, but deployers have the option to use their existing
|
||
certificates, keys, and CA certificates.
|
||
|
||
To learn more about how to customize the deployment of encrypted
|
||
communications, see
|
||
:deploy_guide:`Securing services with SSL certificates <app-advanced-config-sslcertificates.html>`.
|
||
|
||
Host security hardening
|
||
~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
OpenStack-Ansible provides a comprehensive `security hardening role`_ that
|
||
applies over 200 security configurations as recommended by the `Security
|
||
Technical Implementation Guide`_ (STIG) provided by the `Defense Information
|
||
Systems Agency`_ (DISA). These security configurations are widely used and are
|
||
distributed in the public domain by the United States government.
|
||
|
||
Host security hardening is required by several compliance and regulatory
|
||
programs, such as the `Payment Card Industry Data Security Standard`_ (PCI
|
||
DSS) (Requirement 2.2).
|
||
|
||
By default, OpenStack-Ansible automatically applies the security hardening role
|
||
to all deployments. The role has been carefully designed to perform as follows:
|
||
|
||
* Apply nondisruptively to a production OpenStack environment
|
||
* Balance security with OpenStack performance and functionality
|
||
* Run as quickly as possible
|
||
|
||
For more information about configuring the role in OpenStack-Ansible, see
|
||
:ref:`security_hardening`.
|
||
|
||
.. _security hardening role: http://docs.openstack.org/developer/openstack-ansible-security/
|
||
.. _Security Technical Implementation Guide: https://en.wikipedia.org/wiki/Security_Technical_Implementation_Guide
|
||
.. _Defense Information Systems Agency: http://www.disa.mil/
|
||
.. _Payment Card Industry Data Security Standard: https://www.pcisecuritystandards.org/pci_security/
|
||
|
||
Isolation
|
||
~~~~~~~~~
|
||
|
||
By default, OpenStack-Ansible provides isolation by default between the
|
||
containers that run the OpenStack infrastructure (control plane) services and
|
||
also between the virtual machines that end users spawn within the deployment.
|
||
This isolation is critical because it can prevent container or virtual machine
|
||
breakouts, or at least reduce the damage that breakouts might cause.
|
||
|
||
The `Linux Security Modules`_ (LSM) framework allows administrators to set
|
||
`mandatory access controls`_ (MAC) on a Linux system. MAC is different than
|
||
`discretionary access controls`_ (DAC) because the kernel enforces strict
|
||
policies that no user can bypass. Although any user might be able to
|
||
change a DAC policy (such as ``chown bob secret.txt``), only the ``root`` user
|
||
can alter a MAC policy.
|
||
|
||
OpenStack-Ansible currently uses `AppArmor`_ to provide MAC policies on
|
||
infrastructure servers and hypervisors. The AppArmor configuration sets the
|
||
access policies to prevent one container from accessing the data of another
|
||
container. For virtual machines, ``libvirtd`` uses the `sVirt`_ extensions to
|
||
ensure that one virtual machine cannot access the data or devices from another
|
||
virtual machine.
|
||
|
||
These policies are applied and governed at the kernel level. Any process that
|
||
violates a policy is denied access to the resource. All denials are logged
|
||
in ``auditd`` and are available at ``/var/log/audit/audit.log``.
|
||
|
||
.. _Linux Security Modules: https://en.wikipedia.org/wiki/Linux_Security_Modules
|
||
.. _mandatory access controls: https://en.wikipedia.org/wiki/Mandatory_access_control
|
||
.. _discretionary access controls: https://en.wikipedia.org/wiki/Discretionary_access_control
|
||
.. _AppArmor: https://en.wikipedia.org/wiki/AppArmor
|
||
.. _sVirt: https://fedoraproject.org/wiki/Features/SVirt_Mandatory_Access_Control
|
||
|
||
Least privilege
|
||
~~~~~~~~~~~~~~~
|
||
|
||
The `principle of least privilege`_ is used throughout OpenStack-Ansible to
|
||
limit the damage that could be caused if an attacker gains access to any
|
||
credentials.
|
||
|
||
OpenStack-Ansible configures unique username and password combinations for
|
||
each service that interacts with RabbitMQ and Galera/MariaDB. Each service that
|
||
connects to RabbitMQ uses a separate virtual host for publishing and consuming
|
||
messages. The MariaDB users for each service are only granted access only to
|
||
the databases that they need to query.
|
||
|
||
.. _principle of least privilege: https://en.wikipedia.org/wiki/Principle_of_least_privilege
|
||
|
||
.. _least-access-openstack-services:
|
||
|
||
Securing network access to OpenStack services
|
||
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|
||
|
||
OpenStack clouds provide many services to end users, that enable them to build
|
||
instances, provision storage, and create networks. Each of these services
|
||
exposes one or more service ports and API endpoints to the network.
|
||
|
||
However, some of the services within an OpenStack cloud are accessible to
|
||
all end users, while others are accessible only to administrators or
|
||
operators on a secured network.
|
||
|
||
* Services that *all end users* can access
|
||
|
||
* These services include Compute (nova), Object Storage (swift), Networking
|
||
(neutron), and Image (glance).
|
||
* These services should be offered on a sufficiently restricted network that
|
||
still allows all end users to access the services.
|
||
* A firewall must be used to restrict access to the network.
|
||
|
||
* Services that *only administrators or operators* can access
|
||
|
||
* These services include MariaDB, Memcached, RabbitMQ, and the admin
|
||
API endpoint for the Identity (keystone) service.
|
||
* These services *must* be offered on a highly restricted network that is
|
||
available only to administrative users.
|
||
* A firewall must be used to restrict access to the network.
|
||
|
||
Limiting access to these networks has several benefits:
|
||
|
||
* Allows for network monitoring and alerting
|
||
* Prevents unauthorized network surveillance
|
||
* Reduces the chance of credential theft
|
||
* Reduces damage from unknown or unpatched service vulnerabilities
|
||
|
||
OpenStack-Ansible deploys HAProxy back ends for each service and restricts
|
||
access for highly sensitive services by making them available only on the
|
||
management network. Deployers with external load balancers must ensure that the
|
||
back ends are configured securely and that firewalls prevent traffic from
|
||
crossing between networks.
|
||
|
||
For more information about recommended network policies for OpenStack clouds,
|
||
see the `API endpoint process isolation and policy`_ section of the
|
||
`OpenStack Security Guide`_
|
||
|
||
.. _API endpoint process isolation and policy: http://docs.openstack.org/security-guide/api-endpoints/api-endpoint-configuration-recommendations.html#network-policy
|
||
.. _OpenStack Security Guide: http://docs.openstack.org/security-guide
|