ftpde

ftpd was originally created by mtheall. A fork - FTP-GMX - was created which added CIA builds and customizable graphics, though it stagnated and also broke native builds.

This is upstream ftpd (for the most part) with FTP-GMX's (working) changes merged in, plus:

Option handling from terminals. Run ftpde -h for more info.
Extra commands not yet in ftpd and FTP-GMX.
Better root prefix handling.
Better security, including user/pass and proper write rejection.
Configurable behavior.
Color on, color off!

Configuration files

For an example config file, see extra/ftpde.conf.

Custom Graphics on 3DS

You have two choices, depending on your control freak level. One requires building from source code.

Graphics (Simple)

The only file which can be replaced at runtime is 'app_bottom.png'. See extra/ftpde.conf for info.

Graphics (Hacker method)

Modify the .png files in the gfx folder to add your own graphics. These have no effect when building for a POSIX system, since it's purely a console tool.

** app_banner ** This image will appear on the top screen when the application is highlighted (.cia)

** app_bottom ** This is the builtin static in-app image on the bottom screen.

** app_icon ** This is the icon for the .cia and .3dsx.

Features

Appears to work well with a variety of clients, including wget, curl, and gftp.
Also compiles for most POSIX systems, with additional extensions to allow use in a more serious and secure manner as an actual ftp server for desktop. This has been mostly tested on linux, but even mingw might work.
Supports a configuration backend which allows changing some parameter defaults.
Supports user credentials.
Supports multiple simultaneous clients. The 3DS itself only appears to support enough sockets to perform 4-5 simultaneous data transfers, so it will help if you limit your FTP client to this many parallel requests.
Custom graphics on 3DS. Defaults are non-flashy, but hey, you can get fancy.

Reporting issues

Please check if an issue is reported here. Also check mtheall/ftpd and FTP-GMX first. Don't dupe.
If you file an issue which is a feature request I will either consider it, or close it immediately and tell you why.

Before building

** For 3DS **

Install and set up devkitARM.

You also need the following host tools:

There's a bug on linux with makerom - check the issue tracker.

Additionally, I don't recommend building with the bundled libyaml and polarssl if you're a security freak. libyaml is easy to unbundle, but polarssl needs some changes. I recommend being a crazy bastard and building everything yourself.

You'll need the following target libs:

Git version of ctrulib.
sf2dlib
portlibs, preferrably from the portlibs subdir of this repo. dkpro's contain known security issues. You need at minimum zlib, libpng, and libconfig.
sfillib

** For POSIX systems **

Make sure you have the dev package for your system, as well as the headers. I'll not provide specific instructions, since I assume enough technical competency to figure this out. You need at minimum a functional gcc, libpng, zlib, and libconfig.

How to build

Either make 3ds or make posix depending on how you plan to use this. With make posix, you may want to set SYSCONFDIR if configuration should not be in /etc.

make 3ds will produce the following files:

ftpde-VER.3dsx - 3dsx relocatable for hbmenu-style loaders.
ftpde-VER.smdh - Fancy graphics for hbmenu.
ftpde-VER.cia - Installable CTR file. Zero-keyed/No crypto, so you'll need CFW.
ftpde-VER.3ds - Encrypted 3DS rom file. No support, I don't own a gateway.

make posix will produce the following files:

ftpde - Binary for current platform.

How to install

** 3DS **

You need to copy the files to your 3DS. Alternatively, you can directly install if you're running CFW and have FBI available with: make HOST=<3ds IP> fbi-install

That said, you need a config file at sd:/ftpde.conf. Not up for debate, because anonymous has no write permissions. You'll need to set up a proper user, as well, since the default combination is not secure.

** POSIX **

make install

You can optionally set PREFIX to specify the install prefix, and SYSCONFDIR to set the configuration path. Default is PREFIX=/usr/local. and SYSCONFDIR=/etc

Implemented commands

ABOR
APPE
CDUP
CWD
DELE
FEAT
HELP
LIST
MDTM
MKD
NLST
NOOP
OPTS
PASV
PWD
QUIT
REST
RETR
RMD
RNFR
RNTO
STAT
STOR
SYST
XCUP
XCWD
XMKD
XPWD
XRMD
SITE
- HELP

New or enhanced commands in ftpde

SIZE - RFC 3659. Unbreaks wget progress, yay.
PASS - Proper credential support
USER - Proper credential support
PORT - Can be configured to only accept same-IP connections to prevent a subclass of connection stealing.

In progress

Commands that have problems

LIST - Needs proper user support, or at very least to specify proper relative permissions. Can actually do ls params FILE on posix. This is only relevant on posix.

Stubbed Commands that need proper functionality

ALLO - Should run fallocate if available.
MODE - Only stream is supported. I'd like to implement the 'Z' extension mode to save bandwidth.
STRU -
TYPE - ASCII mode is needed. Thankfully binary is the one implemented.
STOU
SITE CHMOD - Should function as chmod(1) on a system which supports it. Currently 200 stub.

NYI, but should be implemented

HOST
LANG
LPRT
MLSD

Planned Features

Load config file to memory rather than re-read from disk, SIGUSR1 to reload or configuration option to watch it.
IP whitelist support (high priority)
Rate limiting (possibly)
Random credentials - only one session is allowed to be open, and credentials are generated on start, and regenerated after close. So that a 3ds can be used mostly securely in public places.
Disable overwriting ftpde.conf and app_bottom.png via config option. This is insecure. (Partially implemented for configs)
Rather than waste time rejecting excessive invalid attempts to connect, add the ability to ignore known bad clients. (maybe)

chaoskagami/ftpde