How to Install the latest OpenSSL version from Source on Linux

OpenSSL is a widely used crypto library that implements SSL and TLS protocols to secure communications over computer networks. OpenSSL is widely used by many software like Apache web server, PHP, Postfix and many others. OpenSSL offers support for different cryptographic algorithms such as Chipers (AES, Blowfish, DES, IDEA etc), Cryptographic hash functions (MD5, MD4, SHA-1, SHA-2 etc), and Public-key cryptography (RSA, DSA, Diffie-Hellman key exchange).

In this tutorial, I will show you step-by-step how to install the latest stable OpenSSL version from source on the Ubuntu 18.04 and CentOS 7.5 servers.

What we will do?

1. Install Dependencies
2. Download OpenSSL Source Code
3. Install OpenSSL
1. Compile and Install OpenSSL
2. Configure Link Libraries
3. Configure OpenSSL Binary
4. Testing

Step 1 – Install Dependencies

The first step we must do for compiling the OpenSSL manually from source is installing some package dependencies including the ‘build-essential’ package on Ubuntu, or ‘Development Tools’ package on CentOS.

On Ubuntu 18.04

Update the Ubuntu repository and install package dependencies for software compilation using the apt command below.

sudo apt update
sudo apt install build-essential checkinstall zlib1g-dev -y

On CentOS 7.5

Install the ‘Development Tools’ and some packages libraries using the yum command.

yum group install ‘Development Tools’
yum install perl-core zlib-devel -y

After the installation is complete, go to the next step.

Step 2 – Download OpenSSL

In this tutorial, we will install the latest stable version of OpenSSL – OpenSSL 1.0.2o. You can download the source code from the OpenSSL site.

Go to the ‘/usr/local/src’ directory and download the OpenSSL source code using wget.

cd /usr/local/src/
wget https://www.openssl.org/source/openssl-1.0.2o.tar.gz

Now extract the openssl.tar.gz file, and go to the ‘openssl’ directory.

tar -xf openssl-1.0.2o.tar.gz
cd openssl-1.0.2o

The OpenSSL source code has been downloaded.

Step 3 – Install OpenSSL

Before installing the custom OpenSSL version to the system, let’s check the installed version using the command below.

openssl version -a

Below is my results on Ubuntu 18.04.

And this is on CentOS 7.5.

We will replace the ‘1.1.0g’ version with the latest stable version 1.0.2o.

We will install the new OpenSSL version to the specific directory ‘/usr/local/ssl’, and then enable the Link Libraries of OpenSSL, and configure the new binary PATH for OpenSSL.

– Install and Compile OpenSSL

Go to the openssl downloaded directory ‘/usr/local/src/openssl’.

cd /usr/local/src/openssl-1.0.2o

Configure and compile OpenSSL with commands below.

./config –prefix=/usr/local/ssl –openssldir=/usr/local/ssl shared zlib

make
make test

Wait for the OpenSSL compile process.

Note:

• –prefix and –openssldir = Set the output path of the OpenSSL.
• shared = force to create a shared library.
• zlib = enable the compression using zlib library.

When the compile process is complete, install the OpenSSL using the command below.

make install

OpenSSL is installed in the ‘/usr/local/ssl’ directory.

– Configure Link Libraries

Next, we will configure the shared libraries for OpenSSL. The new OpenSSL binary will load library files from the ‘/usr/local/ssl/lib’ directory.

Go to the ‘/etc/ld.so.conf.d’ directory and create new configuration file ‘openssl-1.0.2o.conf’.

cd /etc/ld.so.conf.d/
vim openssl-1.0.2o.conf

Paste the openssl library path directory.

/usr/local/ssl/lib

Save and exit.

Now reload the dynamic link using the command below.

sudo ldconfig -v

And you will see the OpenSSL libraries on the ‘/usr/local/ssl/lib’ directory has been loaded.

Ubuntu 18.04.

CentOS 7.5.

– Configure OpenSSL Binary

We will replace the default openssl binary ‘/usr/bin/openssl or /bin/openssl’ with the new version ‘/usr/local/ssl/bin/openssl’.

On Ubuntu 18.04

Backup the binary files.

mv /usr/bin/c_rehash /usr/bin/c_rehash.BEKUP
mv /usr/bin/openssl /usr/bin/openssl.BEKUP

Edit the ‘/etc/environment’ file using vim.

vim /etc/environment

Now add the new OpenSSL binary directory as below

PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games:/usr/local/games:/usr/local/ssl/bin"

Save and exit.

Reload the environment file and test new updated binary PATH.

source /etc/environment
echo $PATH

Now check again the OpenSSL binary file.

which openssl

You will get the result as below.

The binary path openssl for Ubuntu has been updated.

On CentOS 7.5

Backup centos OpenSSL binary files.

mv /bin/openssl /bin/openssl.BEKUP

Create new environment files for OpenSSL.

vim /etc/profile.d/openssl.sh

Paste configuration below.

#Set OPENSSL_PATH
OPENSSL_PATH="/usr/local/ssl/bin"
export OPENSSL_PATH
PATH=$PATH:$OPENSSL_PATH
export PATH

Save and exit.

Make the openssl.sh file executable.

chmod +x /etc/profile.d/openssl.sh

Load the OpenSSL environment and check the PATH bin directory using commands below.

source /etc/profile.d/openssl.sh
echo $PATH

Now check the OpenSSL file.

which openssl

You will get the result as below.

The binary path openssl for CentOS has been updated.

Step 4 – Testing

Test the OpenSSL new version using the following command.

openssl version -a

The result on Ubuntu.

Result on CentOS.

The new latest stable version of OpenSSL has been installed from source on Linux Ubuntu 18.04 and CentOS 7.5.

https://wiki.openssl.org/