In this blog post we show how it is possible to run an arbitrary program, script, or execute arbitrary code in reaction to changes and generally events in a PostgreSQL database.
Triggers Database management systems (DBMS) provide mechanisms for defining reactions to certain actions or, in other words, for defining that specific actions should trigger specific reactions. PostgreSQL, the DBMS used by CFEngine Enterprise, is no exception. These triggers can be used for ensuring consistency between tables when changes in one table should be reflected in another table, for recording information about actions, and many other things. PostgreSQL's Overview of Trigger Behavior describes the basics of triggers with the following sentences:
rxdirs has provided a convenient default when setting permissions recursively. When enabled (the default prior to version 3.20.0) a promise to grant read access on a directory is extended to also include execution since quite commonly if you want to read a directory you also want to be able to list the files in the directory. However, the convenience comes with the cost of complicating security reviews since the state requested on the surface is more strict than what is actually granted. This can both undermine the understanding of the desired state of the permissions as well as confidence that the policy accurately describes the resulting state and we have decided the convenience is not worth the cost.
Saint Patrick’s Day makes us think of the color green. Spring is coming. Plants are starting to sprout amongst the dead grass and leaves from Fall/Winter:
Earth Day is just around the corner on April 22nd.
This reminds us of our commitment to the environment and ecosystems that surround us. As we at Northern.tech state in our corporate social responsibilities:
We have set an ambitious company-objective to “Become a net-zero carbon business by the end of 2022”.
Last year, we launched functionality for users to add policy for reporting data, compliance reports, promise types, and other code as modules. With CFEngine Build, users can manage and update their own policy, the default policy and any additional modules separately. This makes it very easy to utilize policy or other modules written by the CFEngine team, or other community members. In this post we will take a look at using some modules to improve the security of our infrastructure.
The CFEngine engineering team has recently discovered two security issues in the CFEngine Enterprise product, specifically in the hub package:
CVE-2021-44215 - PostgreSQL log file world readable. CVE-2021-44216 - Apache and Mission Portal Application log files world readable. CVE-2021-44215 is a regression affecting currently supported versions 3.18.0 and 3.15.4 as well as some unsupported versions. CVE-2021-44216 affects all supported versions prior to 3.18.1 and 3.15.5 as well as some unsupported versions.
Interested in the efforts underway to make CFEngine manage the environment even faster?
Vratislav (Software Engineer) joins the show to talk about cf-reactor
Video The video recording is available on YouTube:
At the end of every webinar, we stop the recording for a nice and relaxed, off-the-record chat with attendees. Join the next webinar to not miss this discussion.
I re-stumbled across this mailing list post from Bryan Burke about some policy framework upgrade issues where he also asked about hooking in and customizing the update policy. I thought this sounded like a good opportunity for an example using a cfbs module. So, let’s take a look at making a cfbs module for a custom update policy.
As mentioned in the thread there are just a couple of things you need to do in order to hook in and customize the behavior of the update policy.
Last year we had a look at managing local groups with the custom groups promise type. As you may or may not recall, we used JSON-strings to imitate CFEngine bodies. This was due to the fact that the promise module protocol did not support bodies at that time. Today, on the other hand, we’re happy to announce that as of CFEngine 3.20, this will no longer be the case. In this blog post we’ll introduce the long awaited feature; custom bodies. We’ll have a look at it from both the policy writers- and the promise module developers point of view.
CFEngine and Ansible are two complementary infrastructure management tools. Findings from our analysis show that they can be combined and used side by side with joint forces to handle all areas in the best possible way. Part of infrastructure management is hosts deployment, either when building a brand new infrastructure or when growing one by adding new hosts. This is something Ansible truly excels in as it makes it very easy to run a sequence of steps on all hosts to initialize (deploy) them and it only requires SSH access to the hosts and Python installed on them. 1
With the recent release of build.cfengine.com and cfbs I have been thinking about the process of converting a traditionally manged policy set. I consider a traditionally manged policy set one where you have a repo with the root of masterfiles being the root of the repository, or even having no repository at all and managing masterfiles by editing directly in the distribution point (e.g. /var/cfengine/masterfiles). Before jumping in with both feet and converting to a cfbs managed policy set you might want a hybrid situation where you can leverage some of the benefits of cfbs but without making drastic changes to the way policy is currently managed. That’s what this post is about, using cfbs with your traditionally manged policy set. Note: This post assumes that you already have cfbs installed and understand the basics of how it works. Check out our previous blog posts if you want to review how to get started with cfbs.
