certexp

This software can extract certifcate expiry information for given domains.

Usage

Create a text file with a list of domains to check. Please insert one domain per line.

Example (assuming you are in the source code directory):

echo "v-gar.de" >> domainlist.txt; echo "vgapps.de" >> domainlist.txt

Then run certexp:

bin/certexp domainlist.txt

The output looks like this:

Domain: v-gar.de
Expire date: Sun Dec  2 06:35:01 2019
 (expires in 71 days)
 (SAN: v-gar.de)
Expire date: Sun Dec  2 06:35:01 2019
 (expires in 71 days)
 (SAN: *.v-gar.de)

Domain: vgapps.de
Expire date: Sun Dec  6 07:55:27 2019
 (expires in 75 days)
 (SAN: www.vgapps.de)
Expire date: Sun Dec  6 07:55:27 2019
 (expires in 75 days)
 (SAN: vgapps.de)

Compile and install

This software is written in C++ (C++17 standard) and uses libcurl.

You need:

• a C++ compiler: gcc >= 8
• cmake >= 3.2
• libcurl

For Ubuntu / Debian you can install this software using apt:

sudo apt install build-essential cmake libcurl4-openssl-dev

Compilation is easy: go to this source code directory and do:

mkdir build
cd build
cmake ..
make
make install

The binary will be copied/installed to the ./bin/ dir.

License

The code is licensed under the MIT license. See COPYING.