FtpServer

This repository consists of two projects: the library and the server. The library Zhaobang.FtpServer is an FTP library supporting .NET Standard 1.4 and .NET Standard 2.1. The server Zhaobang.FtpServer.Cli is an FTP server written on .NET Core 3.0.

Zhaobang.FtpServer

A FTP library for .NET Standard 1.4 and .NET Standard 2.1. It can be used in .NET Core and UWP projects. It supports customized authenticator, file provider, and data connection provider.

Build Status:

Get stable release:

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Simple Usage

The server allows anonymous login, and users can read and write in a public directory.

To start the server

// using System.Net;
// using System.Threading;
// using Zhaobang.FtpServer;

var endPoint = new IPEndPoint(IPAddress.Any, 21);
// To accept IPv6 connection, replace "IPAddress.Any" with "IPAddress.IPv6Any"
// You need 2 FtpServer instances to accept both IPv4 and IPv6 connectins

var baseDirectory = "C:\\FtpServer";
var server = new FtpServer(endPoint, baseDirectory);

var cancelSource = new CancellationTokenSource();
var runResult = server.RunAsync(cancelSource.Token);

To stop the server

cancelSource.Cancel(); // Stop accepting new clients
await runResult; // Wait until last client quits

Customization

The server allows developer to use customized authentication, file provider, data connection and stream encrytion.

Implement Zhaobang.FtpServer.File.IFileProviderFactory to use custom file system. The default one is SimpleFileProvider, which allow all users to read and write in a single directory.

Implement Zhaobang.FtpServer.Connections.IDataConnectionFactory to use custom data connection, (for example, establish data connection from another server). The default one is LocalDataConnectionFactory, which establish data connection from local server. Use SslLocalDataConnectionFactory (available only on .NET Standard 2.1) to support TLS on data connection.

Implement Zhaobang.FtpServer.Authenticate.IAuthenticator to use custom authentication. The default one is AnonymousAuthenticator, which only allows anonymous logins.

(Optional) (since version 2.1.0) Provide an implementation of Zhaobang.FtpServer.Connections.IControlConnectionSslFactory to support TLS on control connection. An implementation class ControlConnectionSslFactory is provided on the .NET Standard 2.1 version.

Use the following to start your customized server:

var server = new FtpServer(
    localEP,
    new MyFileProviderFactory(),
    new MyDataConnectionFactory(),
    new MyAuthenticator(),
    new MyControlConnectionSslFactory()
);
// the remaining is same as simple use

FTP over TLS support (since version 2.1.0)

TLS on data connection is enabled when IDataConnection instances created by IDataConnectionDataFactory instance implement interface ISslDataConnection.

TLS on control connection is enabled when an instance of IControlConnectionSslFactory is passed to the constructor of FtpServer.

The .NET Standard 2.1 version has out-of-box FTP over TLS support. Example:

var fileProviderFactory = new SimpleFileProviderFactory(config.BaseDirectory);
var dataConnectionFactory = new SslLocalDataConnectionFactory(certificate);
var authenticator = new AnonymousAuthenticator();
var controlConnectionSslFactory = new ControlConnectionSslFactory(certificate);
var server = new FtpServer(ep, fileProviderFactory, dataConnectionFactory, authenticator, controlConnectionSslFactory);

The .NET Standard 1.4 version requires your own implementation of those classes. You can refer to the source code for a sample implementation.

Zhaobang.FtpServer.Cli

The server is a simple FTP server that utilizes the library.

Feature

Set up a server for anonymous read and write.

Usage

Download a release and run, then a default configuration "RunConfig.xml" will be created. The server will listen for IPv4 and IPv6 connections, and allow anonymous users to read and write at the running directory.

Configuration

The config file is at ./RunConfig.xml (depends on where you run the program). If it's not found, a default one will be created.

EndPoints

The local end points to listen at different addresses and ports. Note: Address and Port are the value on the server.

BaseDirectory

The FTP base directory.

CertificatePath

The path to a PKCS7 certificate file to support FTP over TLS. Keep it empty to disable FTP over TLS.

CertificatePassword

The password of the certificate file.

Default configuration file

The default content of RunConfig.xml:

<?xml version="1.0"?>
<RunConfig xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema">
  <EndPoints>
    <IPEndPointData Address="0.0.0.0" Port="21" />
    <IPEndPointData Address="::" Port="21" />
  </EndPoints>
  <BaseDirectory>./</BaseDirectory>
  <CertificatePath />
  <CertificatePassword />
</RunConfig>