OpenSSL tool

Introduction to OpenSSL tool

SSL certificates are now in high demand. Since Google’s “HTTPS Everywhere” campaign, the encryption landscape is changing considerably. They initially gave digital certificates an SEO boost as an inducement to install them, and then Chrome made HTTPS nearly necessary for everyone. Popular browsers like Firefox and Chrome will label that website as Not Secure if you don’t use an SSL certificate.SSL deployment is critical to the success and security of a website. And, because so many website owners are learning about SSL for the first time, it’s critical to provide them with all of the necessary tools and services. OpenSSL is one such utility. In this topic, we are going to learn about the OpenSSL tool.

What is OpenSSL?

Open SSL is a general-purpose cryptography package that implements the TLS protocol in an open-source manner. It is available for Windows, Linux, macOS, as well as BSD computers, and was first released in 1998. Users can use OpenSSL to execute a variety of SSL-related operations, such as generating CSRs and private keys, as well as installing SSL certificates.

What is the purpose of OpenSSL?

User applies for a digital certificate and installs SSL files on the server using OpenSSL Generate the Certificate Signing Request). You can also convert your certificate to different SSL formats and do additional verifications.

How to use OpenSSL?

It’s all about the command lines in OpenSSL. We’ve included a list of typical OpenSSL commands for individual users below.

Make sure you’re using the most recent version of OpenSSL.

Knowing what version of OpenSSL you have is critical since it dictates the cryptographic algorithms and protocols you may use.

the most recent OpenSSL release was 1.1.1. It’s the first version to provide support for TLS 1.3. 1.0.2 and 1.1.0 are two previous releases that are still supported.

Run the following command to see what version of OpenSSL you have:

openssl version–a

CSR Generation

Users can generate their own CSR code with OpenSSL. A CSR is a block of encoded text that contains information about the website and business. Users should submit the CSR for approval to the Certificate Authority. A private key is required for the certificate request, from which the public key is generated. While you can utilise a current private key, it’s best to produce a fresh one every time users create a CSR.

How to Generate private keys separately?

Users must specify the key algorithm, key size, and an alternate passphrase to produce your private key. RSA is The typical key algorithm, however, ECDSA can be used in some cases. Make sure users won’t have any compatibility difficulties while selecting a key algorithm.

When utilising the RSA key algorithm, choose 2048 bits for key size, and 256 bits for the ECDSA algorithm. Any key size less than 2048 is insecure, while a greater value may cause performance to suffer.

Then, users must determine whether or not a passphrase is required for the private key.  some servers will refuse to accept private keys with passwords.

Run the commands below whenever ready to produce a private key (using the RSA algorithm):

opensslgenrsa -out domain.key 2048

The domain.key file will be created in your current directory using this command. The PEM format will be used to store your private key.

The encoded contents of your private key can be viewed with the following command:

cat domain.key

Run the following command to decode the private key:

opensslrsa -text -in domain.key -noout

How to Extract public key?

To extract the public key from the private key, the following command is used:

opensslrsa -in domain.key -pubout -out domain_public.key

Generate a Certificate Signing Request

It’s time to build CSR after you’re successfully generating the private key. It will be in PEM format and will contain information about the business and the public key generated from the private key. To generate a CSR, use the following command:

opensslreq -new -key domain.key -out domain.csr

user will be asked a few questions by OpenSSL. Consider the following situations:

1. Country Name: Enter country’s two-letter code. Make sure the country user submit his the organization’s official residence if the user has a Business Validation or Extended Validation certificate.
2. Name of State/Province: enter the complete name of the state in which the user’s business is registered.
3. Name of Locality: Enter the name of the city or town where the company is located.
4. Organization Name: enter your company’s official registered name. For Domain Validation certificates, for example, users can use NA
5. Organization Unit Name: it’s commonly Web Administration.
6. Common Name: Enter the Fully Qualified Domain Name (FQDN) to which your SSL certificate will be assigned. Consider the domain educba.com. Add an asterisk in front of the domain name (e.g. *.educba.com) to activate a wildcard certificate.
7. Email Address: Give a valid email address.
8. A challenging password: It is an out-of-date characteristic that the Certificate Authorities no longer require. If there is any confusion, leave this box blank.

Verify the certificate’s information

After CA sends an SSL certificate, execute the command below to make that the certificate’s information matches the private key.

openssl x509 -text -in domain.crt –noout

Conclusion – OpenSSL tool

In this article, we have seen the list of popular OpenSSL commands. If you want to learn more about OpenSSL and how it works.

Recommended Articles

This is a guide to OpenSSL tool. Here we discuss the list of popular OpenSSL commands and learned more about OpenSSL and how it works. You may also have a look at the following articles to learn more –

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