Installation

Prerequisites

A docker file is provided to ease the installation of Cingulata. The following steps suppose that you have a functional docker installation. For more details about docker and its installation steps refer to docker install.

Compilation

Cingulata with B/FV backend

Build a docker image with packages required for Cingulata in B/FV mode build:

docker build -t cingulata:bfv -f Dockerfile.bfv --build-arg uid=$(id -u) .

Create a container from cingulata:bfv image with current folder as a docker volume and run it with no command:

docker run -it --rm -v $(pwd):/cingu cingulata:bfv

The default command of this docker image compiles Cingulata and all its tests. So each time you modify Cingulata code you should call this command to recompile the changes.

After this step, in the current directory a folder build_bfv is created. This folder contains compilation outputs and artifacts.

Cingulata with TFHE library backend

Cingulata in TFHE mode is compiled equivalently:

docker build -t cingulata:tfhe -f Dockerfile.tfhe --build-arg uid=$(id -u) .
docker run -it --rm -v $(pwd):/cingu cingulata:tfhe

Similarly, a folder build_tfhe is created containing compilation outputs and artifacts.

Run your first homomorphic encryption application

Congratulations! If you arrived at this point, you successfully installed Cingulata and are ready to take at look at our examples. Their input codes and the running scripts are situated in the tests directory. More precisely:

• tests/bfv -- tests using B/FV homomorphic encryption scheme

• tests/tfhe -- tests using TFHE homomorphic encryption library

• tests/old_bfv -- tests using B/FV homomorphic encryption scheme and the old circuit front-end (these tests will be removed in next release)

Suppose now that you want to run your first -- homomorphic hello world -- test.

B/FV mode

You can do it directly using the following docker command:

docker run -it --rm -v $(pwd):/cingu cingulata:bfv bash -c "cd build_bfv/tests/bfv/hello && bash run.sh"

Or...

You can enter the docker container:

docker run -it --rm -v $(pwd):/cingu cingulata:bfv bash

You should go to the corresponding directory from build_bfv/tests/bfv:

cd build_bfv/tests/bfv/hello

And finally, execute the test:

bash run.sh

In both cases and if all went well, you should obtain an execution trace similar to the one below:

FHE key generation
Input encryption
Command line arguments:
FHE parameters file fhe_params.xml
Public key file fhe_key.pk
Encrypting message [1] into file input/i:a_0.ct
Encrypting message [0] into file input/i:a_1.ct
Encrypting message [1] into file input/i:a_2.ct
Encrypting message [0] into file input/i:a_3.ct
Encrypting message [0] into file input/i:a_4.ct
Encrypting message [0] into file input/i:a_5.ct
Encrypting message [0] into file input/i:a_6.ct
Encrypting message [0] into file input/i:a_7.ct
Command line arguments:
FHE parameters file fhe_params.xml
Public key file fhe_key.pk
Encrypting message [1] into file input/i:b_0.ct
Encrypting message [1] into file input/i:b_1.ct
Encrypting message [0] into file input/i:b_2.ct
Encrypting message [0] into file input/i:b_3.ct
Encrypting message [0] into file input/i:b_4.ct
Encrypting message [0] into file input/i:b_5.ct
Encrypting message [0] into file input/i:b_6.ct
Encrypting message [0] into file input/i:b_7.ct
Homomorphic execution...
Total execution real time 4.66193 seconds
CPU time:
READ time 0.0661443 seconds, #execs 16
COPY time 0.0380457 seconds, #execs 71
XOR gates execution time 0.0448051 seconds, #execs 24
NOT gates execution time 0.0138237 seconds, #execs 20
AND gates execution time 4.17691 seconds, #execs 18
OR gates execution time 0.240259 seconds, #execs 1
WRITE time 0.0249645 seconds, #execs 16
Maximal number of simultaneously allocated ciphertexts 23

real  0m4.694s
user  0m4.601s
sys 0m0.092s
Output decryption
8

So the decrypted result is 8, since the test hello performs a simple addition of two integers: 5 and 3!

TFHE mode

Running the hello world application with TFHE crypto-system is almost the same in Cingulata. Use the following docker command:

docker run -it --rm -v $(pwd):/cingu cingulata:tfhe bash -c "cd build_tfhe/tests/tfhe/hello && bash run.sh"

The output after for TFHE mode is more sober but the execution is faster:

Input encryption
TFHE key generation
Homomorphic execution...

real  0m0.615s
user  0m0.543s
sys 0m0.072s
Output decryption
8

If you want to go further and see how you can write and execute a program using Cingulata, check our tutorial page.

Cingulata B/FV mode -- default security values

• BKZ reduction model cost defaults to bkz_sieve.
• Required minimum security defaults to 128.

These values are CMake cache entries. To change the default security level, replace line

cmake -DUSE_BFV=ON ..

in Cingulata B/FV dockerfile Dockerfile.bfv with

cmake -DUSE_BFV=ON -DMIN_SECU=192 -DMODEL=bkz_enum ..

Database values are given at: https://github.com/CEA-LIST/CinguParam/wiki#database-values

selectParams.sh

• Location: runtime/fhe\_fv/script

• Usage: The script is called during build phase.

• Goal: It searches for a parameter set in the database suited for three constraints:

  • multiplicative depth
  • BKZ reduction model cost
  • required security level lambda

Default value

There are two modes of selection : static (default value) and interactive. Both are described below. The mode is hard-coded in selectParams.sh. You can modify it manually.

Static mode

If no parameter set is found with given constraints, it establishes the list of parameter sets in the database with:

• given multiplicative depth
• given bkz reduction cost model
• security level in the interval [lambda-8,lambda+56]

It picks a parameter set into it. If the list is empty, it switches to the interactive mode.

Interactive mode

If no parameter set is found with given constraints, it lets the user select with yad tool, a parameter set in the database. It is flexible, the user can modify the three constraints.

Additionally, it permits the database to be updated using the HEAD commit of the LWE-Estimator, if new version is available.