1. Introduction

Data and user security have always been important considerations for small to large enterprises during the deployment of their database or application servers. PostgreSQL today has rich support for many network level and user level security features. These include TLS to secure database connections, internal user authentication, integration with external user authentication services such as RADIUS, LDAP and GSSAPI, and TLS certificate based user authentication …etc. However, it does not yet support Transparent Data Encryption (TDE) feature where all the database files and logs have an option to be encrypted before written to disk or decrypted when retrieving from the disk. This adds extra security measure to protect against disk theft.

All these features have something in common; they all use cryptographic keys (either symmetrical or asymmetrical, statically generated or exchanged on the fly using Diffie Hellman) in some ways to achieve the security goals. It is quite common for an organization to focus entirely on the actual data encryption part but pay minimal attention to the cryptographic keys that make the encryption possible. In fact, data encryption is the easy part, the protection of the cryptographic keys is often the hardest as it has several levels of complexities.

1. Introduction

This is part 3 of the blog “Understanding Security Features in PostgreSQL”, in which I will be discussing how to apply TLS in both PostgreSQL server and client using the principles we have learned in part 2 of the blog. In the end, I will also briefly talk about Transparent Data Encryption (TDE) and security vulnerability.

1. Introduction

This is part 2 of the blog “Understanding Security Features in PostgreSQL”, in which I will be discussing TLS in greater details. I will begin by going over some of the most important security concepts around TLS before jumping into enabling TLS on PostgreSQL server. I believe it is crucial to have sufficient background information on TLS before tweaking the TLS settings in both client and server sides.

In part 1 of this blog, we mostly discussed about authentication and authorization (AA), which is important to identify which client is permitted to connect and which table or column he/she is permitted to operate. Even with the strongest authentication and authorization, the actual communication between client and server will not be encrypted unless Transport Layer Security (TLS) is specifically enabled in the database server. TLS is one of the least understood but commonly used security protocol that ensures the security of many HTTPS sites and other services. TLS is a big protocol and this blog will describe how it works and how to enable TLS in your PostgreSQL server.

1. Introduction

PostgreSQL is packed with several security features for a database administrator to utilize according to his or her organizational security needs. The word Security is a very broad concept and could refer to completely different procedures and methodology to achieve in different PostgreSQL components. This blog is divided into part 1, 2 and 3 and I will explain the word Security with regards to PostgreSQL version 12.1 and how it is practiced in different areas within the system.

In Part 1 of the blog, I will be discussing the basic security features that exist in PostgreSQL with emphasis on Host-based authentication methods as well as user-based access control with the concept of roles. If done right, we could have a much more robust database server and potentially reduce the attack surface on the server, protecting it from attacks like SQL injections. I will also briefly discuss a few of the advanced authentication methods such as LDAP and PAM authentication. There are many more advanced authentication methods supported and we will be producing more articles in the near future to cover more of these methods.

In Part 2 of the blog, I will be discussing TLS in greater detail, which I believe is crucial for a database administrator to understand first before enabling TLS in the PostgreSQL server. TLS is a fairly large and one of the least understood protocol today, which contains a lot of security components and methodology related to cryptography that could be quite confusing.

In Part 3 of the blog, I will be discussing how to apply TLS configurations to both PostgreSQL server and client following the TLS principles that have been discussed in Part 2. I will also briefly discuss Transparent Data Encryption (TDE) that the PG community is currently working on that introduces another layer of secured database environment.