Mirror of Covert Channel Application on the RWTH Aachen GitLab.

Pflanzer, Jonas f3850bac77 Merge branch 'cli-more-status-info' into 'develop' 4 years ago
.cmake_modules 5e1a4565bd rework CMakeLists into one per directory with one top-level file to build all. get boilerplate for cmdman_test up, also test for version command. 4 years ago
cli 856ce375bf US53: CLI adjust output of status command to show username and IP/port 4 years ago
daemon d4bab1905c Daemon installation notes improved 4 years ago
gui e1bc06b674 Resolve "US52: GUI supports SSL file" 4 years ago
libs 22fd34e7c6 Link to bcrypt instead of liblibbcrypt.a.a 4 years ago
.clang-format 9b51e01701 ColumnLimit now at 160 4 years ago
.gitignore 7a76a90805 update gitignore to ignore build folders 5 years ago
.gitlab-ci.yml f100fe23bc US49: Hashed password on server 4 years ago
CMakeLists.txt 64bf674a00 Set Daemon file path properly for crypto tests 4 years ago
Client-Server Protocol.md a3351c8ca9 US45.2: Extendedlist (CLI) 4 years ago
Dockerfile f100fe23bc US49: Hashed password on server 4 years ago
Dockerfile.testing f100fe23bc US49: Hashed password on server 4 years ago
GUI-CLI Protocol.md 56ebe6309f Fix isDecryptable crashing on empty data argument, add unknown as result for bad signature or filesize, minor formatting fixes for extendedlist output in user and batchmodes 4 years ago
LICENSE b2211fe6e3 GPL License 5 years ago
README.md 6e6cf373e1 Build notices 4 years ago
autoformat.sh 99263a8448 Adjust filters for passiveMode again 4 years ago

README.md

CCats - Covert Channels are Tricky Stuff

CCats is a covert channel tool which works as man in the middle. Our motivation is to create a tool which allows you to send files over a covert channel between two controlled servers.

This repository consists of three programs: a server (daemon), a CLI-client and a GUI-client.

The server manages the uploaded files and transmits the files over the covert channel. The clients let you connect and login to the server and upload files and start file transmission over the covert channel.

The basic setup

   A           -----------------                        ------------------           B
   o  traffic  |               |                        |                |  traffic  o
  /|\ ---------| active Server | <== covert channel ==> | passive Server |--------- /|\
   \\          |               |                        |                |          //
               -----------------                        ------------------
                      ||                                       ||
               client connection                        client connection
                      ||                                       ||
               E  ----------                               ----------  F
               o  |        |                               |        |  o
              /|\ | Client |                               | Client | /|\
               \\ |        |                               |        | //
                  ----------                               ----------

E wants to send a file to F. A and E live together and B and F live together. E and F know that A will surf on B's website a lot so they decided to setup a covert channel which utilises the traffic of A and B as man in the middle.
A surfs on the website of B on Port p and produces traffic between them. E and F set up the two servers. The active server is the server which will be used to send a file to the passive server.
E sets the target IP on the active server side to the IP of A and F the target IP on the passive side to the IP of B. The target Port on both sides is set to p. Now the servers are forwarding A's and B's traffic and can add secret data to the traffic.
E connects to the active server with his/her client and queues a file for sending over the covert channel. The file transmission will start once A surfs on B's website again. Now E and F have to wait until A produced enough traffic to transmit the file completely. After the file transmission finished F can downlod the file with his/her client.

Encryption

E and F can decide to use a common key for symmetrical encryption. Files will be encrypted on the client side so the servers cannot read the files as plain data. The covert channel does not add another encryption-layer so it's encouraged to use this feature.

Dependencies

  • libtins >=4.2
  • Jsoncpp
  • Boost >=1.70
  • GNU Readline
  • OpenSSL
  • Qt5 (Core, Quick, Widgets)

Dependencies for testing

  • GTest
  • GMock

Installing dependencies on Ubuntu

Packages to install after minimal Ubuntu 19.10 installation:

sudo apt install qtdeclarative5-dev libboost-all-dev libjsoncpp-dev libreadline-dev libpcap-dev build-essential qml-module-qt-labs-platform libssl-dev

(NOTE: because of bug in jsoncpp, in the file size field of the gui, all numbers after the decimal point are displayed as 0. This bug occurs in version 1.7.4 and is fixed in 1.9.1 (or possibly earlier))

Install libtins

mkdir libtins
cd libtins
git clone https://github.com/mfontanini/libtins.git
sudo apt-get install libpcap-dev libssl-dev cmake
cd libtins
mkdir build
cd build
cmake ../ -DLIBTINS_ENABLE_CXX11=1
make
sudo make install
sudo ldconfig

Install boost

mkdir boost
cd boost
wget https://dl.bintray.com/boostorg/release/1.72.0/source/boost_1_72_0.tar.gz
tar -xf boost_1_72_0.tar.gz
cd boost_1_72_0
./bootstrap.sh
./b2
sudo ./b2 install

Build and install googletest

git clone https://github.com/google/googletest.git
cd googletest
mkdir build
cd build
cmake ..
make
make install
cd ../..
rm -rf googletest

Build

CMake is used as build system. It should check which dependency is missing and tell you.

mkdir build
cd build
cmake ..
make

Build with tests

mkdir build
cd build
cmake .. -DENABLE_TESTS=true
make