CSharp-AES-CTR-NetStandard

Managed .Net (Standard 2.0, .NET 6 and .NET 8) compatible AES-CTR cipher written in C# (using Aes.Create for AES operations)

Build status

Why?

Because I needed this for my personal project

Documentation

Docs

How do I use this?

Either copy the CSAES-CTR.cs to your project or use LibAES-CTR nuget package

Then do code like

using CS_AES_CTR;

byte[] mySimpleTextAsBytes = Encoding.ASCII.GetBytes("Plain text I want to encrypt");

// In real world, generate these with cryptographically secure pseudo-random number generator (CSPRNG)
byte[] key = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 };
byte[] initialCounter = new byte[] { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05 };

// Encrypt
AES_CTR forEncrypting = new AES_CTR(key, initialCounter);			
byte[] encryptedContent = new byte[mySimpleTextAsBytes.Length];
forEncrypting.EncryptBytes(encryptedContent, mySimpleTextAsBytes);

// Decrypt
AES_CTR forDecrypting = new AES_CTR(key, initialCounter);
byte[] decryptedContent = new byte[encryptedContent.Length];
forDecrypting.DecryptBytes(decryptedContent, encryptedContent);

You can try out the code in .NET Fiddle

Test cases

You can run test cases by moving to tests folder and running following command

dotnet test

Benchmarks

You can run benchmarks (which compare this implementation to the original version) by moving to benchmarks folder and running following command

dotnet run -c Release

there are three different input sizes (64 bytes, 1024 bytes and 1 MiB) and comparisons are done between code from Stack Overflow (made by Martin Prikryl) and this project

License

All the code in src and tests folders are licensed under Unlicense. SO sample code file (which is only used during benchmarking) is licensed under cc-wiki (aka cc-by-sa) license, see https://stackoverflow.blog/2009/06/25/attribution-required/