vncpasswd.py

Python implementation of vncpasswd, w/decryption abilities & extra features ;-) Tested on Python 2.7.3. (Does not currently work with Python 3)

List of Extra Features:

• File input and output
• Decryption / Password recovery!
• Supports RealVNC long passwords!
• Hex input and output
• Read/Write to windows RealVNC registry key

Long password decryption tested against RealVNC Enterprise Edition, version: E4.5.3 (r39012) 64-bit (x64) unicode

Windows Registry I/O tested on Windows 7 x64 Professional

Sponsor

If you find this project useful and appreciate my work, would you be willing to click one of the buttons below to Sponsor this project and help me continue?

• ❤️ Sponsor
• 
• 

Python Installation:

This python script was built with and only supports Python 2! If you are from the future, or accessing this via the GitHub Arctic Code Vault 02/02/2020, First of all... congratulations on surviving! If this code is useful to you, you may need to obtain a version of Python 2.7. Alternatively, you may use the Python 2to3 utility to convert this source code for use with Python 3 (may take some testing & development to get working on all platforms).

To install Python 2.7.17 (Latest version as of 01/28/2020. Python 2 End of Life was 01/01/2020):

macOS / Linux:

If your system does not have an available python2 in PATH linked:

# Make sure you have build dependencies installed on your platform:
# For example: GNU make, gcc / g++ compiler, build-essential package, etc...
# Find and/or download Python 2.7
curl -L -o /tmp/python-v2.7.17.tar.gz https://github.com/python/cpython/archive/v2.7.17.tar.gz
tar -xvf /tmp/python-v2.7.17.tar.gz
cd cpython-2.7.17/
./configure
make
sudo make install
# OR: sudo make altinstall

# Symlink `python2` to the resulting python2.7 binary
# For example:
ln -sf /usr/local/bin/python2.7 /usr/local/bin/python2

Alternatively, use pyenv:

• If on macOS, Homebrew method is preferred:

    brew install pyenv
  

• Otherwise, install via pyenv-installer script & restart your shell:

    curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash
    exec $SHELL
  

• Build & Compile Python 2.7

    pyenv install 2.7.17
  

• Use pyenv in a shell with:

    eval "$(pyenv init - )"
  

Windows:

To install Python and get familiar with Visual Studio's Python development tools on Windows platforms, refer to Getting Started with Python in VS Code. The official Python Downloads page should have .msi installers available for your Windows platform: (x86-64 MSI installer, x86 MSI installer).

Building cPython

Building cPython on Windows, is a more advanced topic that is out of scope for this guide. Please refer to the python/cpython/PCbuild/readme.txt for Windows-specific build instructions (Microsoft Visual Studio 2017). The basic idea is to make sure you have build & compilation dependencies installed for Windows platform, and run the build.bat script.

Excerpt:

Building Python using the build.bat script

In this directory you can find build.bat, a script designed to make building Python on Windows simpler. This script will use the env.bat script to detect either Visual Studio 2017 or 2015, either of which may be used to build Python. Currently Visual Studio 2017 is officially supported.

By default, build.bat will build Python in Release configuration for the 32-bit Win32 platform. It accepts several arguments to change this behavior, try build.bat -h to learn more.

More modern versions of VS Code have Extensions for Python and CMake support. You may wish to refer to Getting Started with Python in VS Code. In addition, Windows Subsystem for Linux may allow you to run, and build this project using native Linux tools. Again, this is beyond the scope of this guide because it is assumed that you know how to use these tools if you need them.

Installation:

This project installs from source via:

git clone https://github.com/trinitronx/vncpasswd.py.git vncpasswd.py
cd vncpasswd.py
python2 ./vncpasswd.py --help

Note: The "shebang" line at the top of the python script is: #!/usr/bin/env python2

If you have python2, and /usr/bin/env binaries available in your system's PATH, you should be all set up to just run the executable script file as-is: ./vncpasswd.py

On Windows, this command will work in PowerShell. However, it will open a cmd.exe window and close it too quickly to see any output. If you require an interactive terminal experience, run with python.exe. For example

python.exe .\vncpasswd.py --help

To build a Docker image, or Python Source Distribution, see below or run make help to see all available Makefile targets.

Usage:

The help output explains the command line flags:

usage: vncpasswd.py [-h] [-d] [-e] [-H] [-R] [-f FILENAME] [-t] [passwd]

Encrypt or Decrypt a VNC password

positional arguments: passwd A password to encrypt

optional arguments:

-h, --help show this help message and exit

-d, --decrypt Decrypt an obfuscated password.

-e, --encrypt Encrypt a plaintext password. (default mode)

-H, --hex Assume input is in hex.

-R, --registry Input or Output to the windows registry.

-f FILENAME, --file FILENAME

                    Input or Output to a specified file.

-t, --test Run the unit tests for this program.

Docker:

The docker container is ready-built with all dependencies needed. Just mount in your file (e.g.: -v $HOME/.vnc/:$HOME/.vnc, or just -v $HOME:$HOME), and run:

# Decrypt ~/.vnc/passwd
docker run -ti -v $HOME:$HOME -w $HOME  trinitronx/vncpasswd.py -d -f ~/.vnc/passwd

# More Examples:
# Encrypt string 'foo'
docker run  -v $HOME:$HOME -w $HOME -ti trinitronx/vncpasswd.py -e 'foo'
# Encrypt string 'bar' and output to ~/.vnc/passwd
mkdir -p $HOME/.vnc/
docker run  -v $HOME:$HOME -w $HOME -ti trinitronx/vncpasswd.py -e 'foo' -f ~/.vnc/passwd
# Encrypt string 'bar' as HEX input
docker run  -v $HOME:$HOME -w $HOME -ti trinitronx/vncpasswd.py -e -H '6261720000000000'
# Decrypt the encrypted password 'bar' as HEX input
docker run  -v $HOME:$HOME -w $HOME -ti trinitronx/vncpasswd.py -d -H '9ca3f3686574f277'

Testing:

This project used TravisCI for Continuous Integration & Continuous Deployment to Docker Hub. The .travis.yml contains the build steps. To manually run the tests for this project:

make test

Python Source Distribution:

First install build dependencies from ./build/build-requirements.txt.

make build-depends

Note: This should run the following command. You may need to use pip2 depending on your installed python version.

pip install --user -r ./build-aux/build-requirements.txt

To create a python source distribution via setuptools:

make setup

Output files are placed in dist/ directory.

Python Binary Distribution:

First install build dependencies from ./build/build-requirements.txt.

make build-depends

To create a python binary distribution via setuptools:

make bdist

Output files are placed in dist/ directory.

Python RPM Distribution:

First install build dependencies from ./build/build-requirements.txt. Make sure you are on a RHEL / CentOS compatible system, with rpm installed.

make build-depends

To create a python RPM distribution via setuptools:

make bdist_rpm

Output files are placed in dist/ directory.

Python Windows self-extracting .zip Distribution:

First install build dependencies from ./build/build-requirements.txt. Make sure you are on a Windows compatible system, with compilation tools installed.

pip install --user -r ./build/build-requirements.txt

To create a python binary Windows .exe self-extracting .zip distribution via setuptools:

make bdist_wininst
# Or, without GNU Make:
python setup.py bdist_wininst

Output files are placed in dist/ directory.

Python site-packages Install:

First install build dependencies from ./build/build-requirements.txt.

pip install --user -r ./build/build-requirements.txt

To install this into your system site-packages Python directory:

make install

Installed bits include:

• Python Libraries:
  • d3des: A Minimalistic DES implementation d3des.py Python Library (Source from mythbuntu-common 0.72)
  • WindowsRegistry: A Python class to simplify read/write access to the Windows Registry
• This project's scripts / package info:
  • vncpasswd.py: The main executable Python script for this project.
  • pass2reg.cmd: A Windows batch script file that takes a password and writes it to the UltraVNC registry area. Calls out to vncpasswd.py -o -e %1, to encrypt the password first. Note: It can also be saved to the RealVNC registry location directly with Python via vncpasswd.py --registry. Originally part of Mike Miller's blog post.
  • vncpasswd.py-1.2.1-py2.7.egg Python Egg package of this project
  • vncpasswd.py-1.2.1_-py2.7.egg-info Python Egg packaging metadata for this project

Docker Image Build:

Make sure you have Docker installed on your system, and run:

make package

DockerHub / Repository Image Ship:

To ship this image to either DockerHub, or your Docker Image repository of choice, just export the following variables:

DOCKER_USERNAME=your-username
DOCKER_PASSWORD=your-password

Then run:

# DockerHub by default
make ship

# Alternate Repository
#  Override & export these variables set in `./build/main.mk`:
#    REGISTRY    ?= docker.io
#    REPO_NAME   ?= $(BIN)
#    REPO        ?= $(REGISTRY)/trinitronx/$(REPO_NAME)
export REGISTRY=quay.io
export REPO_NAME=your-reponame
export USERNAME=your-username
export REPO=$REGISTRY/$USERNAME/$REPO_NAME
make ship

Thanks / Props

Many thanks to the original authors of the d3des libary (Richard Outerbridge, Dan Hoey, Jim Gillogly, Phil Karn, et. al.), and it's python rewrite (Yusuke Shinyama)! Thanks to Mike Miller for his great blog post on how he used the d3des.py library. Thanks to Darren McCall for his wonderful collection of RealVNC Registry Hacks And finally... Thanks to God for the inspiration to reverse engineer RealVNC's multi-block method for encrypting long passwords ;-D (Long story... recovering my long RealVNC password saved a bunch of my data!)

Disclaimer:

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

Please only use this software for Good, and don't harm directly or indirectly living beings

References:

• Creating a Hashed Password for VNC
• RealVNC Password Hacking
• Email Thread: Registry Edit to define server password
• Email Thread on User vs. System passwords: Password Shift