# Installation

## Downloading Kryptor

Pre-built binaries for Windows (x64), Linux (x64 and ARM64), and macOS (x64 and ARM64) are available on the [Introduction](/master.md#download-kryptor) page.

Kryptor is also available as a package from [several package managers](/master.md#download-kryptor), although **help is wanted** to make it available elsewhere.

## Building Kryptor from source

### Downloading the source code

1. Go to the [**latest release**](https://github.com/samuel-lucas6/Kryptor/releases/latest) on GitHub and download the `Source code (zip)` asset.
2. Navigate to the download location and extract the ZIP file.

{% hint style="warning" %}
Do **NOT** download the source code from the *master* branch.
{% endhint %}

### Using the .NET CLI

1. Install the latest [.NET 8 SDK](https://dotnet.microsoft.com/en-us/download/dotnet/8.0). This may be newer than the SDK and runtime version used to build the release files.
2. Navigate to the `src` folder in the terminal (e.g. `cd Downloads\Kryptor-4.0.0\src`).
3. Copy and paste the following command for the operating system and architecture you'd like to build for:

#### Windows (x64)

```bash
dotnet publish -c Release -r win-x64
```

{% hint style="info" %}
The [libsodium](https://doc.libsodium.org/) library requires the [Visual C++ Redistributable for Visual Studio 2015-2022](https://learn.microsoft.com/en-us/cpp/windows/latest-supported-vc-redist?view=msvc-170) to work on Windows. However, the appropriate `vcruntime140.dll` is automatically written to disk by Kryptor.
{% endhint %}

#### Linux (x64)

```bash
dotnet publish -c Release -r linux-x64
```

#### macOS (x64)

```bash
dotnet publish -c Release -r osx-x64
```

{% hint style="warning" %}
**For macOS (x64/ARM64)**, there is currently an [upstream issue](https://github.com/dotnet/sdk/issues/45903) in the .NET SDK that prevents the libsodium library from being bundled correctly into the Kryptor executable. The .NET team has not investigated this for over a year, so this is unlikely to be fixed.

Until this is resolved, you must keep the `libsodium.dylib` file (from the `publish` folder) in the same directory as the `kryptor` file.
{% endhint %}

#### Linux (ARM64)

```bash
dotnet publish -c Release -r linux-arm64
```

#### macOS (ARM64)

```bash
dotnet publish -c Release -r osx-arm64
```

{% hint style="warning" %}
Publishing for `osx-arm64` [requires](https://github.com/dotnet/runtime/discussions/66574) using macOS because Apple Silicon Macs require code signing.
{% endhint %}

{% hint style="warning" %}
**For macOS (x64/ARM64)**, there is currently an [upstream issue](https://github.com/dotnet/sdk/issues/45903) in the .NET SDK that prevents the libsodium library from being bundled correctly into the Kryptor executable. The .NET team has not investigated this for over a year, so this is unlikely to be fixed.

Until this is resolved, you must keep the `libsodium.dylib` file (from the `publish` folder) in the same directory as the `kryptor` file.
{% endhint %}

#### Linux (ARM)

```bash
dotnet publish -c Release -r linux-arm
```

{% hint style="warning" %}
`win-arm64` isn't supported yet. Currently, `linux-arm`, `linux-arm64`, `linux-musl-arm64`, and `linux-musl-x64` are not tested. Better support and testing are on the [roadmap](/roadmap.md).
{% endhint %}

{% hint style="info" %}
A full list of .NET CLI publish options can be found [here](https://docs.microsoft.com/en-us/dotnet/core/tools/dotnet-publish). The settings Kryptor uses can be found in the [Kryptor.csproj](https://github.com/samuel-lucas6/Kryptor/blob/master/src/Kryptor/Kryptor.csproj) file.
{% endhint %}

## Verifying signatures

If you already have Kryptor installed, you can use the previous version to verify the `.signature` file for your new download.

{% hint style="info" %}
If you don't have a previous version of Kryptor installed, you should follow the [Verifying digests](#verifying-digests) section below instead.
{% endhint %}

1. Download the signature file for your version of Kryptor [here](/master.md#download-kryptor).
2. Make sure the `.signature` file is in the same directory as the downloaded Kryptor `.zip` file.
3. Open the `Command Prompt` on Windows (e.g. search for `cmd` in the taskbar) or the `terminal` on Linux and macOS (e.g. search your programs for `terminal`).
4. For v4 and above, copy and paste the following command, replacing `[file]` with the file path of the Kryptor `.zip` file:

```bash
kryptor -v -y Ed//bnY+xqUXVMaaI0poBwTqDRlKA9+x9FjlDAHE9MmXKG4= "[file]"
```

For v3, use the following command instead:

```bash
kryptor -v -y RWRudj7GpRdUxpojSmgHBOoNGUoD37H0WOUMAcT0yZcobg== "[file]"
```

Kryptor should display the message '`Good signature`', followed by the authenticated comment '`Kryptor v[version]`'.

{% hint style="danger" %}
If you see '`Bad signature`', your download is either corrupted or not legitimate and may be unsafe.​
{% endhint %}

## Verifying digests

### Windows

1. Download the latest SHA-256 `.digest` file [here](/master.md#download-kryptor).
2. Open a `PowerShell` window (e.g. search `PowerShell` in the taskbar).
3. Navigate to the directory of the downloaded Kryptor `.zip` file (e.g. `cd Downloads`).
4. Copy and paste the following command into PowerShell:

```powershell
(Get-FileHash .\kryptor-windows-x64.zip).Hash -eq (Get-Content .\kryptor-windows-x64.zip.digest).split(" ")[0].ToUpper()
```

The word `True` should appear in the `PowerShell` window.

{% hint style="danger" %}
If you see `False`, your download is either corrupted or not legitimate and may be unsafe.​
{% endhint %}

### Linux and macOS

1. Download the latest SHA-256 `.digest` file [here](/master.md#download-kryptor).
2. Open a `terminal` window (e.g. search your programs for `terminal`).
3. Navigate to the directory of the downloaded Kryptor `.zip` file (e.g. `cd Downloads`).
4. Copy and paste the following command, replacing `[file]` with the file name of the `.zip` file:

```bash
shasum -a 256 -c [file].digest
```

The word `OK` should appear.

{% hint style="danger" %}
If you see another message, your download is either corrupted or not legitimate and may be unsafe.​
{% endhint %}


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