<PackageReference Include="BouncyCastle.Cryptography" Version="2.3.1" />

Org.BouncyCastle.Crypto.Macs.Poly1305

public class Poly1305 : IMac
Poly1305 message authentication code, designed by D. J. Bernstein.
namespace Org.BouncyCastle.Crypto.Macs { public class Poly1305 : IMac { public string AlgorithmName { get; } public Poly1305(); public Poly1305(IBlockCipher cipher); public void Init(ICipherParameters parameters); public int GetMacSize(); public void Update(byte input); public void BlockUpdate(byte[] input, int inOff, int len); public void BlockUpdate(ReadOnlySpan<byte> input); public int DoFinal(byte[] output, int outOff); public int DoFinal(Span<byte> output); public void Reset(); } }