Tag: Integrations

Encrypting/Decrypting a file using Public & Private Key Pair with GnuPG

Hi Folks,

Thank you for visiting my blog today…this is post is mainly for Pro developers. Encryption is crucial to maintain the confidentiality in this digital age for the security of our sensitive information. So here is a blog about it. This is in continuation to my previous blog post on encrypting files using GnuPG.

In this blog post, I will give you sample how you can encrypt/decrypt using GnuPG with command line scripts from C# code.

If you didn’t go through my previous article, I strongly recommend you go through that article below first to understand the background.

Installing GnuPG – Your open-source software companion to encrypt/decrypt files for your Power Platform Integrations

Next, in order to encrypt/decrypt a given csv file (taken for simplicity), we can use the following C# codes. For illustration purpose, I have just provided you the logic in the form of a Console.

Encryption:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
namespace eHintsBatchDecryptionTest
{
class Program
{
static void Main(string[] args)
{
string gpgPath = @"D:\Softwares\Kleo Patra\GnuPG\bin\gpg.exe"; //This is the place where you have installed GnuPG Software
string inputFile = "location of input file";
string outputFile = "location of output file";
string passphrase = "passPhrase";
DecryptGPGFile(gpgPath, inputFile, outputFile, passphrase);
}
static void DecryptGPGFile(string gpgPath, string inputFile, string outputFile, string passphrase)
{
using (Process process = new Process())
{
process.StartInfo.FileName = gpgPath;
process.StartInfo.Arguments = $"–batch –yes –pinentry-mode=loopback –passphrase {passphrase} -d -o \"{outputFile}\" \"{inputFile}\"";
process.StartInfo.UseShellExecute = false;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.RedirectStandardInput = true;
process.StartInfo.CreateNoWindow = true;
process.Start();
string output = process.StandardOutput.ReadToEnd();
string error = process.StandardError.ReadToEnd();
process.WaitForExit();
if (process.ExitCode == 0)
{
Console.WriteLine("Decryption successful.");
}
else
{
Console.WriteLine("Decryption failed. Error: " + error);
}
}
}
}
}
view raw Encrypt csv file using GnuPG from C# using command line hosted with ❤ by GitHub

Decryption:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;
namespace BatchDecryptionTest
{
class Program
{
static void Main(string[] args)
{
string gpgPath = @"D:\Softwares\Kleo patra\GnuPG\bin\gpg.exe";//Once GPG installed, you can look for gpg.exe in the bin folder of the installation
string inputFile = "Input encrypted file";//Replace with your gpg encrypted file location
string outputFile = "Decrypted CSV file"; //give it a name for the decrypted file and location, output file path doesnt exists yet, you may give a sample name
string passphrase = "passPhrase";
DecryptGPGFile(gpgPath, inputFile, outputFile, passphrase);
}
static void DecryptGPGFile(string gpgPath, string inputFile, string outputFile, string passphrase)
{
using (Process process = new Process())
{
process.StartInfo.FileName = gpgPath;
process.StartInfo.Arguments = $"–batch –yes –pinentry-mode=loopback –passphrase {passphrase} -d -o \"{outputFile}\" \"{inputFile}\""; //Pass the PassPhrase, Input and Output file paths as parameters
process.StartInfo.UseShellExecute = false;
process.StartInfo.RedirectStandardOutput = true;
process.StartInfo.RedirectStandardError = true;
process.StartInfo.RedirectStandardInput = true;
process.StartInfo.CreateNoWindow = true;
process.Start();
string output = process.StandardOutput.ReadToEnd();
string error = process.StandardError.ReadToEnd();
process.WaitForExit();
if (process.ExitCode == 0)
{
Console.WriteLine("Decryption successful.");
}
else
{
Console.WriteLine("Decryption failed. Error: " + error);
}
}
}
}
}
view raw Decrypt csv file using GnuPG from C# using command line hosted with ❤ by GitHub

All you need is to copy and replace the file locations in the code. Sit back and enjoy encrypting and decrypting with GnuPG. I should say once known, this is the easiest way to encrypt/decrypt from C# code, no strings attached.

If you need any other information, please do let me know in comments.

Cheers,

PMDY

Installing GnuPG – Your open-source software companion to encrypt/decrypt files for your Power Platform Integrations

What’s GnuPG?

GnuPG is a complete and free implementation of the OpenPGP standard. GnuPG allows you to encrypt and sign your data and communications; it features a versatile key management system, along with access modules for all kinds of public key directories. GPG can use both symmetric and asymmetric encryption to encrypt and decrypt.

So, now let’s talk about the tool Gpg4Win. Gpg4win is an email and file encryption package for most versions of Microsoft Windows and Microsoft Outlook, which utilizes the GnuPG framework for symmetric and public-key cryptography, such as data encryption, digital signatures, hash calculations etc. It’s open source and a free tool, it has been widely used by many of the encryption implementations. So, let’s see how you can install a GnuPG Software.

You can navigate to this GnuPG Download link of the official download page. You can download the latest version, as of writing this blog Gpg4Win 4.2.0 is the latest.

Gpg4win 4.2.0 contains mainly, rest of the components aren’t of interest for this blog:

1.GnuPG 2.4.3 : Actual software used to encrypt and decrypt.

2. Kleopatra 3.1.28: Kleopatra is a certificate manager and GUI for GnuPG, it stores all your certificates and keys.

Choose $0 and proceed to download which now

This now downloads the Gpg4Win software. So once click and start your installation, choose the necessary components required.

You can proceed to select only GnuPG, Kleopatra or both, which installs only GnuPG command line and/or Kleopatra which is a windows utility.

If you choose not to install Kleopatra, it’s ok, you still be able to encrypt and decrypt but only using command line, but if you have Kleopatra, you can use GUI for encryption or decryption.

Once you have installed GnuPG, just open Command Prompt, start entering gpg..

You can also check the root folder where all your Key rings will be stored…

With gpg is now set up in your PC, you will be able to encrypt and decrypt using gpg command line scripts.

Ok, now everything is good, how about if other persons when logged into this PC, will they be able to use the gpg commands to encrypt or decrypt, of course not, for this you need to follow as below…

All you need to set an environment variable which is of scope user and set the home location for gpg to look for keys in that machine.

Once you have set this, the home location of gpg is now changed, so any user who have access to this path can be able to encrypt or decrypt without issues.

You check the modified location by using this command

I hope you have learned something…below this post, I have added the link to the blog post where the encryption and decryption just below this blog post, we will see how you can encrypt and decrypt files using gpg command line utility being called from C#. Any questions do let me know in comments….

Happy Integrating Power Platform with 3rd party Applications.

Cheers,

PMDY

Encrypting/Decrypting a file using Public & Private Key Pair with GnuPG