How To Openssl Linux

OpenSSL is an open-source command-line tool that is commonly used to manage private keys, public keys, and certificates. OpenSSL is available for Linux distributions, and it is a powerful tool that can be used to encrypt data and secure network connections. In this blog post, we will look at how to use OpenSSL on Linux.


If OpenSSL is not already installed on your system, you can install it using the package manager for your distribution. For example, on Ubuntu or any other Debian-based distribution, you can install OpenSSL with the following command:

sudo apt-get install openssl

Generating a new private key and Certificate Signing Request (CSR)

One common use of OpenSSL is to generate a private key and a Certificate Signing Request (CSR). These are the first steps in creating an SSL certificate. To generate a new private key and CSR, use the following command:

openssl req -new -newkey rsa:2048 -nodes -keyout domain.key -out domain.csr

This command will create a new RSA private key (domain.key) and a CSR (domain.csr) for the domain you specify when running the command.

Generating a Self-Signed SSL Certificate

You can also use OpenSSL to create a self-signed SSL certificate. This can be useful for testing purposes or for setting up a secure connection on a personal network. Here is the command to generate a self-signed certificate:

openssl req -x509 -newkey rsa:4096 -keyout key.pem -out cert.pem -days 365

Encrypting and Decrypting Files

OpenSSL can also be used to encrypt and decrypt files. To encrypt a file, you would use the following command:

openssl enc -aes-256-cbc -salt -in file.txt -out file.txt.enc

To decrypt the file, you would use this command:

openssl enc -d -aes-256-cbc -in file.txt.enc -out file.txt

In both commands, replace file.txt with the name of the file you wish to encrypt or decrypt.

In conclusion, OpenSSL is a versatile tool that can be used for many different tasks related to secure networking and data management. Its wide range of features make it a valuable addition to any Linux system.