While Encrypting a File with a Password from the Command Line using OpenSSLis very useful in its own right, the real power of the OpenSSL library is itsability to support the use of public key cryptograph for encrypting orvalidating data in an unattended manner (where the password is not required toencrypt) is done with public keys.
Nov 07, 2018. How to generate private key and CSR from command line This article describes how to generate a private key and CSR (Certificate Signing Request) from the command line. You may need to do this if you want to obtain an SSL certificate for a system that does not include cPanel access, such as a dedicated server or unmanaged VPS.
The Commands to RunGenerate a 2048 bit RSA Key
You can generate a public and private RSA key pair like this:
openssl genrsa -des3 -out private.pem 2048
That generates a 2048-bit RSA key pair, encrypts them with a password you provideand writes them to a file. You need to next extract the public key file. You willuse this, for instance, on your web server to encrypt content so that it canonly be read with the private key.
Export the RSA Public Key to a File
This is a command that is
openssl rsa -in private.pem -outform PEM -pubout -out public.pem
The
-pubout flag is really important. Be sure to include it.
Next open the
public.pem and ensure that it starts with-----BEGIN PUBLIC KEY----- . This is how you know that this file is thepublic key of the pair and not a private key.
To check the file from the command line you can use the
less command, like this:
less public.pem
Do Not Run This, it Exports the Private Key
A previous version of the post gave this example in error.
openssl rsa -in private.pem -out private_unencrypted.pem -outform PEM
The error is that the
-pubout was dropped from the end of the command.That changes the meaning of the command from that of exporting the public keyto exporting the private key outside of its encrypted wrapper. Inspecting theoutput file, in this case private_unencrypted.pem clearly shows that the keyis a RSA private key as it starts with -----BEGIN RSA PRIVATE KEY----- .
Visually Inspect Your Key Files
It is important to visually inspect you private and public key files to makesure that they are what you expect. OpenSSL will clearly explain the nature ofthe key block with a
-----BEGIN RSA PRIVATE KEY----- or -----BEGIN PUBLIC KEY----- .
You can use less to inspect each of your two files in turn:
The next section shows a full example of what each key file should look like.
The Generated Key Files
The generated files are base64-encoded encryption keys in plain text format.If you select a password for your private key, its file will be encrypted withyour password. Be sure to remember this password or the key pair becomes useless.
Linux Generate Private Key Ssl ServerThe private.pem file looks something like this:![]() The public key, public.pem, file looks like:Protecting Your Keys
Depending on the nature of the information you will protect, itâs important tokeep the private key backed up and secret. The public key can be distributedanywhere or embedded in your web application scripts, such as in your PHP,Ruby, or other scripts. Again, backup your keys!
Remember, if the key goes away the data encrypted to it is gone. Keeping aprinted copy of the key material in a sealed envelope in a bank safety depositbox is a good way to protect important keys against loss due to fire or harddrive failure.
Oh, and one last thing.
If you, dear reader, were planning any funny business with the private key that I have just published here. Know that they were made especially for this series of blog posts. I do not use them for anything else.
Found an issue?Rietta plans, develops, and maintains applications.
Learn more about our services or drop us your email and we'll e-mail you back.
Other Blog Articles Published by Rietta.com![]()
CSR stands for âCertificate Signing Requestâ, that is generated on the server where the certificate will be used on. A CSR contains information about to your organization and domain name, locality, and country and a public key that will be included in your certificate.
This article has 3 methods to create CSR (Certificate Signing Request) on Linux systems. You can choose any one of below methods. All methods will do the same task, only they have a detailed explanation.
Method 1 â Using Single Command
We can create CSR using the single command like below. But make sure you have installed OpenSSL package on your system. The below command will first create a private key and then generate CSR. This command will also require few details as input.
Method 2 â Short Instructions
Below are three simple commands to generate CSR. You may also use detailed instructions to do it.
Method 3 â Detailed InstructionsStep 1: Install Required Packages.
In order to generate CSR, you required OpenSSL to be installed on your system. If it is not already installed use below command to install it.
Step 2: Generate Key for your Domain.
Firstly you required root access to generate a key file. So login as root and use below command to generate a key.
Sample output:
At the end of the command, it showing 2048, which is the length of the key in bits. Most of CA required 2048 bit length keys. Above command will create a key file tecadmin.net.key, which is used in step 3.
Step 3: Generate CSR for your Domain using Key.
After generating a key, next steps are to generate CSR for the domain. Use below command to generate CSR file, This command will prompt for your organization and common name, locality, email, and country. Common Name must be the same as your domain name.
Linux Generate Private Key Ssl Free
Sample Output:
Above command will generate a file tecadmin.net.csr in the current directory, Use this file to order your SSL from CA (Certificate Authority).
Generate Ssl Public Key
References:
http://wiki.centos.org/HowTos/Https
http://www.centos.org/docs/4/4.5/System_Administration_Guide/Apache_HTTP_Secure_Server_Configuration-Generating_a_Key.html Comments are closed.
|
AuthorWrite something about yourself. No need to be fancy, just an overview. Archives
December 2020
Categories |