### Install Kdf108 NuGet Package

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

Instructions to install the Kdf108 library into a .NET project using the .NET CLI's `dotnet add package` command. This command adds the latest stable version of the Kdf108 package from NuGet to your project's dependencies.

```bash
dotnet add package Kdf108
```

--------------------------------

### Derive Key using Counter Mode with Split Fixed Input

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

Illustrates an advanced usage of `CounterModeKdf` where the fixed input is split into 'before' and 'after' parts, and the counter is inserted in the middle. This example utilizes CMAC-AES128 as the PRF and demonstrates the fluent `KdfOptionsBuilder` for configuration. The derived key is outputted as a hexadecimal string.

```csharp
using Kdf108.Domain.Kdf.Modes;
using Kdf108.Domain.Kdf;

byte[] key = Convert.FromHexString("DFF1E50AC0B69DC40F1051D46C2B069C");
byte[] before = Convert.FromHexString("0011223344");
byte[] after  = Convert.FromHexString("AABBCCDDEE");

var opts = KdfOptions.CreateBuilder()
    .WithPrfType(PrfType.CmacAes128)
    .WithCounterLengthBits(8)
    .WithUseCounter(true)
    .WithCounterLocation(CounterLocation.MiddleFixed)
    .Build();

byte[] result = new CounterModeKdf()
    .DeriveWithSplitFixedInput(key, before, after, 128, opts);
Console.WriteLine(Convert.ToHexString(result));
```

--------------------------------

### Derive Key using NIST SP 800-108 Feedback Mode KDF

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

This example showcases key derivation using the `FeedbackModeKdf`, another mode specified in NIST SP 800-108. It configures HMAC-SHA256 as the PRF, uses an 8-bit counter located before the fixed input, and sets options specifically for feedback mode with a null initialization vector (IV). The resulting derived key is displayed.

```csharp
using Kdf108.Domain.Kdf.Modes;
using Kdf108.Domain.Kdf;

var fbOptions = KdfOptions.CreateBuilder()
    .WithPrfType(PrfType.HmacSha256)
    .WithCounterLengthBits(8)
    .WithUseCounter(true)
    .WithCounterLocation(CounterLocation.BeforeFixed)
    .ForFeedbackMode(iv: null)
    .Build();

byte[] fbKey = new FeedbackModeKdf()
    .DeriveWithFixedInput(kdk, fixedInput, null, 256, fbOptions);
Console.WriteLine(Convert.ToHexString(fbKey));
```

--------------------------------

### Derive Key using NIST SP 800-108 Counter Mode KDF

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

This example demonstrates how to use the `CounterModeKdf` to derive a key according to NIST SP 800-108 Counter Mode. It configures HMAC-SHA256 as the Pseudo-Random Function (PRF), sets the counter length, and specifies the counter's location before the fixed input. The derived key is then printed in hexadecimal format.

```csharp
using Kdf108.Domain.Kdf.Modes;
using Kdf108.Domain.Kdf;

// Key Derivation Key (KDK)
byte[] kdk = Convert.FromHexString("4E6F77206973207468");
// Fixed input (Label || Context)
byte[] fixedInput = System.Text.Encoding.ASCII.GetBytes("LabelAndContext");
long outputBits = 256;

var options = new KdfOptions
{
    PrfType = PrfType.HmacSha256,
    CounterLengthBits = 32,
    UseCounter = true,
    CounterLocation = CounterLocation.BeforeFixed,
    MaxBitsAllowed = outputBits
};

var kdf = new CounterModeKdf();
byte[] derived = kdf.DeriveWithFixedInput(kdk, fixedInput, outputBits, options);
Console.WriteLine(Convert.ToHexString(derived));
```

--------------------------------

### Run Kdf108 Unit and Integration Tests

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

Command to execute the full test suite for the Kdf108 library. These tests include unit tests and validation against NIST SP 800-108 Response Specification (RSP) test vectors, ensuring compliance and correctness of the KDF implementation.

```bash
dotnet test
```

--------------------------------

### Reference Kdf108 Project Directly

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

Demonstrates how to include the Kdf108 library in a .NET project by directly referencing its `.csproj` file. This method is typically used during development within a multi-project solution or for local builds, allowing direct access to the source.

```xml
<ProjectReference Include="src/Kdf108/Kdf108.csproj" />
```

--------------------------------

### Derive Key using NIST SP 800-108 Double-Pipeline Mode KDF

Source: https://github.com/mistial-dev/kdf108/blob/master/docs/README.md

This snippet demonstrates key derivation using the `DoublePipelineKdf` mode, a specific implementation of NIST SP 800-108. It configures HMAC-SHA256 as the PRF, sets a 16-bit counter, and specifies the counter's location before the fixed input, tailored for double-pipeline operation. The derived key is then printed.

```csharp
using Kdf108.Domain.Kdf.Modes;
using Kdf108.Domain.Kdf;

byte[] context = Convert.FromHexString("CAFEBABE");

var dpOptions = KdfOptions.CreateBuilder()
    .WithPrfType(PrfType.HmacSha256)
    .WithCounterLengthBits(16)
    .WithUseCounter(true)
    .WithCounterLocation(CounterLocation.BeforeFixed)
    .ForDoublePipelineMode()
    .Build();

byte[] dpKey = new DoublePipelineKdf(useCounter: true)
    .DeriveKey(kdk, "label", context, 512, dpOptions);
Console.WriteLine(Convert.ToHexString(dpKey));
```

=== COMPLETE CONTENT === This response contains all available snippets from this library. No additional content exists. Do not make further requests.