Enhancing Database Security: Introducing PostgreSQL and sepgsql with SELinux


In today’s world, organizations are collecting and managing vast amounts of data on a daily basis. This data can include sensitive information such as personal identification numbers, credit card information, health records, and more.

With cybercrime on the rise, it is imperative that businesses implement robust security measures to protect their databases from unauthorized access, data breaches and theft. PostgreSQL is a popular open-source relational database management system that provides excellent functionality for handling complex data with high concurrency.

However, ensuring the security of the PostgreSQL database can be challenging due to its default configuration settings which prioritize functionality over security. One solution to this problem is implementing sepgsql with SELinux.

Sepgsql is a PostgreSQL extension designed specifically to provide an additional layer of security by enforcing mandatory access controls on objects in the database. On top of this, SELinux helps enforce policies at the operating system level and provides an added layer of protection for PostgreSQL.

The Importance of Database Security

Database security plays a critical role in protecting sensitive information from external threats and preventing unauthorized access within an organization. Without effective security measures in place, sensitive information can be easily leaked or stolen either intentionally or unintentionally through loopholes or vulnerabilities present within an organization’s database infrastructure. A lack of proper security measures also leaves businesses exposed to various cyber attacks such as SQL injection attacks where hackers exploit vulnerabilities in application code to gain unauthorized access to databases.

Data breaches are costly affairs that can tarnish an organization’s reputation leading to loss of trust from customers which ultimately results in financial losses. For instance, Yahoo Inc suffered a massive cyber attack back in 2013 where 1 billion user accounts were compromised leading to lawsuits and hefty payouts amounting up to $80 million dollars.

How PostgreSQL and sepgsql with SELinux Enhance Database Security

PostgreSQL provides several built-in security features including authentication, authorization, and encryption. However, these features are not enough to provide complete protection against modern-day threats which can be sophisticated and targeted. Sepgsql is an extension for PostgreSQL that enforces mandatory access controls on database objects such as tables, indexes, columns and more.

It provides a set of security policies that can prevent unauthorized access to these objects thus reducing the risk of data loss or theft. SELinux is a mandatory access control mechanism that can be used to enforce policies on system resources including databases.

It acts as an added layer of protection for PostgreSQL by restricting unauthorized users from accessing files or directories that are critical to the operation of the database software. As a result, even if an attacker were to gain access to the database server, they would not be able to exploit vulnerabilities within the application code or operating system itself.

Implementing sepgsql with SELinux provides two layers of defense for protecting PostgreSQL databases. Sepgsql helps protect against internal attacks while SELinux helps protect against external attacks making it an effective solution for organizations concerned about data security.

Understanding PostgreSQL and sepgsql

Overview of PostgreSQL as a Relational Database Management System

PostgreSQL is one of the most popular relational database management systems, known for its ability to handle complex transactions and its wide range of features. It is an open-source database system that has been around since the 1990s, and it has evolved over time to become a highly robust and scalable system. One of the key benefits of PostgreSQL is its ability to handle large volumes of data.

It can manage terabytes of information with ease, making it an ideal choice for large corporations or organizations. Its transactional capabilities also make it a popular choice for applications that require high levels of concurrency and reliability.

Explanation of sepgsql, A Security Extension for PostgreSQL

Sepgsql is a security extension for PostgreSQL that was developed by the National Security Agency (NSA). It provides enhanced security features by enforcing policies on database objects such as tables, views, and functions.

Sepgsql effectively reduces the risk of attacks on your database system by restricting access to sensitive information. With sepgsql, you can define policies to restrict access based on user roles or labels.

For example, you can specify that only certain users can read or write specific tables in your database. This level of control gives you greater visibility into who has access to your data at all times.

Benefits Of Using sepgsql With PostgreSQL For Enhanced Security

The combination of PostgreSQL and sepgsql offers several benefits when it comes to enhancing security in your database environment. Firstly, sepgsql provides more granular control over access privileges than traditional role-based security models used in other databases. This means that you can restrict access at a much finer level within your organization – preventing unauthorized users from accessing data they shouldn’t have access to.

Secondly, since sepgsql was developed specifically with PostgreSQL in mind, it integrates seamlessly with the database engine. This makes it easier to implement and maintain, as well as providing a more stable and secure platform for your data.

Overall, the use of sepgsql with PostgreSQL is an excellent way to enhance security in your database environment. With its granular access controls and seamless integration with PostgreSQL, sepgsql provides a level of security that is unmatched by other databases.

Understanding SELinux

Overview of SELinux as a mandatory access control mechanism

Security-Enhanced Linux (SELinux) is a Linux kernel security module that provides a comprehensive set of mandatory access control (MAC) mechanisms to enforce policies on system resources. It was developed by the United States National Security Agency (NSA) and has been integrated into many mainstream Linux distributions, including Red Hat Enterprise Linux, CentOS, Fedora, and Ubuntu.

SELinux is different from traditional Unix-style discretionary access control (DAC) mechanisms in that it uses MAC to determine whether an application or a user can access specific system resources, such as files, directories, devices or network ports. Under MAC policies enforced by SELinux, each process is assigned a security context that defines its permissions and restrictions on accessing system resources based on the principle of “least privilege”.

Explanation of how SELinux can be used to enforce policies on system resources

In order to enforce MAC policies on system resources with SELinux, administrators need to define security contexts for objects such as files and processes. A security context consists of three elements: the user identity (UID), the role identity (RID), and the domain identity (SID). The SID represents a set of permissions and restrictions that are associated with the object being protected.

Administrators also need to define policy rules that specify which subjects are allowed or denied access to objects based on their security contexts. These rules are defined in policy files stored in /etc/selinux directory, where they can be managed with tools such as semanage and audit2allow.

Benefits of using SELinux with PostgreSQL and sepgsql for enhanced security

Using SELinux in conjunction with PostgreSQL and sepgsql can greatly enhance database security by enforcing strict MAC policies on all database-related operations. For example, administrators can configure SELinux to allow only trusted users and applications to access the PostgreSQL database files and directories, thus reducing the risk of unauthorized access or data leaks caused by malware or other security breaches. SELinux can also provide granular access control to specific database objects such as tables, views, or stored procedures based on their security contexts.

This means that even if an attacker manages to compromise a user account with limited privileges, they will not be able to escalate their privileges and gain unrestricted access to the entire database. SELinux can be used in conjunction with other advanced security features of PostgreSQL such as row-level security, encryption, and auditing to provide a comprehensive defense-in-depth approach for protecting sensitive data stored in databases.

Implementing PostgreSQL and sepgsql with SELinux

Setting up PostgreSQL and sepgsql

To begin, you will need to install PostgreSQL and sepgsql on your Linux server. In this example, we will be using CentOS 7 as the operating system.

First, you will need to add the PostgreSQL repository to your system: “` sudo yum install https://download.postgresql.org/pub/repos/yum/reporpms/EL-7-x86_64/pgdg-redhat-repo-latest.noarch.rpm “`

Next, install PostgreSQL and its dependencies: “` sudo yum install postgresql11-server postgresql11-contrib postgresql11-devel “`

Once installed, initialize the database cluster: “` sudo /usr/pgsql-11/bin/postgresql-11-setup initdb “`

Now that we have PostgreSQL set up, let’s move on to installing sepgsql. To do this, we’ll need to download the source code for sepgsql from Github: “`

git clone https://github.com/SELinuxProject/selinux.git cd selinux/

make -C policy/sepgsql/ make -C policy/sepgsql/ install

/sbin/restorecon -R /usr/share/pgsql “` With these steps complete, you should now have a working installation of both PostgreSQL and sepgsql.

Configuring SELinux policies for enhanced security

Now that we have our software installed, it’s time to configure SELinux policies to protect our database. By default, SELinux is set to “permissive” mode which means it logs actions that would otherwise be denied but does not actually enforce any policies.

However for security purposes we want it in “enforcing” mode which strictly enforces policies. Before setting modes run `sestatus` command which gives status of SELinux running on the system. “`

sestatus “` To set enforcing mode: “`

sudo setenforce 1 “` We will now create the policy file that SELinux will use to enforce policies on PostgreSQL.

We’ll start by creating a directory for our policy file: “` mkdir /etc/selinux/targeted/modules/active/sepgsql/ “`

Next, create and edit the policy file: “` vi /etc/selinux/targeted/modules/active/sepgsql/postgresql.mod “`

Insert this module: “` module pgsql 1.0;

require { type init_t;

type postgresql_t; class process execmem; }

#============= postgresql_t ============== allow postgresql_t self:process execmem; #======================================== “`

Now we will generate a binary SELinux module from our policy file: “` checkmodule -M -m -o postgres.mod postgres.te

semodule_package –outfile=postgresql.pp –module=postgresql.mod semodule -i postgresql.pp “`

The last command installs our new SElinux module. With these steps complete, SELinux is now configured to enforce policies on PostgreSQL and sepgsql for enhanced security.

Best practices for configuring policies in SELinux

When configuring policies with SELinux, it’s important to follow best practices to ensure your database is adequately protected. Some best practices include:

– Regularly reviewing and updating your policies to adapt to changes in your system or security requirements. – Creating custom policies tailored to your specific needs rather than relying solely on defaults.

– Using role-based access control (RBAC) to restrict access based on user roles and privileges. – Enforcing separation of duties by assigning different tasks such as database administration and system administration to different users or groups.

– Regularly monitoring logs and audit trails for suspicious activity. By following these best practices, you can ensure that your PostgreSQL database is well-protected with SELinux policies.

Advanced Security Features in PostgreSQL and sepgsql

Overview of Advanced Security Features

PostgreSQL offers advanced security features to maximize database protection. One of these is the row-level security (RLS) feature, which allows for finer-grained access control that restricts users from accessing specific rows of data.

This feature uses policies to limit row access by user group or role, enabling you to keep your valuable data secure and confidential. Another important security feature in PostgreSQL is encryption.

PostgreSQL offers different encryption options such as column-level encryption, tablespace level encryption, or even overall disk-level encryption. Encrypting sensitive data ensures that it remains secure even if the database is breached.

Auditing is another essential tool for ensuring the integrity and accountability of your database system. PostgreSQL provides a robust auditing subsystem known as pgAudit, which enables organizations to audit and monitor activities such as SQL statements executed against the database server, session information, and network traffic behavior.

Implementation with sepgsql

sepgsql can be used to enforce RLS policies and ensure proper access control at the row-level. This is done by mapping SELinux contexts with roles in the database system.

For example, an SELinux context could be assigned to an admin role within the database with permissions to modify all rows in a table. Encryption can also be implemented through sepgsql using Trusted Path Execution (TPE).

TPE ensures that only authorized applications can execute specific functions related to managing encrypted data. In addition, audit logs generated by pgAudit can also be secured using sepgsql policies.

Overall, utilizing PostgreSQL’s advanced security features alongside sepgsql can provide an extra layer of protection for your organization’s valuable data assets. By implementing these features correctly with sepgsql policies and best practices in SELinux configuration management you will create a robust security posture that keeps cyber attackers at bay while giving your team peace of mind.

Case Studies: Real World Examples

The U.S. Department of Defense (DoD)

The U.S. DoD is one of the largest organizations in the world and has some of the most sensitive and valuable data to protect. In 2016, they began using PostgreSQL, sepgsql, and SELinux to secure their databases.

They found that this combination provided a strong foundation for database security by ensuring that only authorized users could access sensitive information. The DoD also noted that implementing this solution reduced their risk surface by eliminating vulnerabilities in their old system.

IBM Watson Health

IBM Watson Health is a leading provider of solutions to the healthcare industry. They use PostgreSQL with sepgsql and SELinux to manage large datasets containing highly sensitive patient information. IBM Watson Health found that using this combination made it easier for them to maintain compliance with healthcare industry regulations such as HIPAA, while still enabling them to provide fast access to accurate data for medical professionals.

Khan Academy

Khan Academy is an educational non-profit organization that provides free online courses on various subjects worldwide. They began using PostgreSQL with sepgsql and SELinux in 2015 after experiencing several security breaches on their previous system. After implementing this solution, they noted a significant reduction in security incidents as well as improved performance due to the efficient management of large datasets.

Analysis on the Impact

The impact of implementing PostgreSQL with sepgsql and SELinux can be significant for organizations looking to enhance their database security measures. This combination provides an enhanced level of protection against unauthorized access, hacking attempts, and malicious software attacks which can cause severe damage if not detected early enough. Additionally, implementing these technologies can help organizations comply with industry regulations surrounding data privacy and protection such as GDPR or HIPAA increasing customer trust while reducing legal risk.

Furthermore, databases secured with PostgreSQL and sepgsql with SELinux can be more efficient and cost-effective to operate compared to less secure systems. Reduced hacking attempts, fewer security incidents, and decreased data breaches can result in lower operational costs, as well as increasing overall data quality.


PostgreSQL with sepgsql and SELinux is a powerful solution for enhancing database security that has been successfully implemented across various industries. The combination allows organizations to manage large datasets while ensuring the protection of sensitive information from unauthorized access. Additionally, it reduces the risk surface by eliminating vulnerabilities in older systems.

Implementing this solution can also help organizations comply with industry regulations such as HIPAA and GDPR while reducing legal risk associated with insecure databases. The resulting operational efficiency is a cost-effective choice for organizations looking to protect their data from malicious attacks while increasing overall performance.

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