Cosmian KMS

Cosmian KMS is an implementation of a high-performance, massively scalable, Key Management System that presents some unique features, such as

• the ability to confidentially run in a public cloud — or any zero-trust environment — using Cosmian VM (see Cosmian VM) and application-level encryption (see Redis-Findex)
• a JSON KMIP 2.1 compliant interface
• support for object tagging to easily manage keys and secrets
• a full-featured command line and graphical interface (CLI)
• Python, Javascript, Dart, Rust, C/C++, and Java clients (see the cloudproof libraries on Cosmian Github)
• FIPS 140-3 mode gated behind the feature fips
• support for the Proteccio HSM with KMS keys wrapped by the HSM
• out-of-the-box support of Google Workspace Client Side Encryption (CSE)
• out-of-the-box support of Microsoft Double Key Encryption (DKE)
• Veracrypt and LUKS disk encryption support

The KMS has extensive online documentation

The KMS can manage keys and secrets used with a comprehensive list of common (AES, ECIES, ...) and Cosmian advanced cryptographic stacks such as Covercrypt. Keys can be wrapped and unwrapped using RSA, ECIES or RFC5649/AES KWP.

• Cosmian KMS
  • Quick start
    • Example
  • Repository content
  • Building the KMS
    • Linux or MacOS (CPU Intel or MacOs ARM)
    • Windows
    • Build the KMS
    • Build the Docker Ubuntu container
  • Running the unit and integration tests
  • Development: running the server with cargo
  • Setup as a Supervisor service
  • Server parameters
  • Use the KMS inside a Cosmian VM on SEV/TDX
  • Releases
  • Benchmarks

Quick start

Pre-built binaries are available for Linux, MacOS, and Windows, as well as Docker images. To run the server binary, OpenSSL must be available in your path (see "building the KMS" below for details); other binaries do not have this requirement.

Using Docker to quick-start a Cosmian KMS server on http://localhost:9998 that stores its data inside the container, run the following command:

docker run -p 9998:9998 --name kms ghcr.io/cosmian/kms:4.20.0

Then, use the CLI to issue commands to the KMS. The CLI, called ckms, can be either downloaded from Cosmian packages or built and launched from this GitHub project by running

cargo run --bin ckms -- --help

Example

1. Create a 256-bit symmetric key

➜ cargo run --bin ckms -- sym keys create --number-of-bits 256 --algorithm aes --tag my-key-file
...
The symmetric key was successfully generated.
   Unique identifier: 87e9e2a8-4538-4701-aa8c-e3af94e44a9e

  Tags:
    - my-key-file

2. Encrypt the image.png file with AES GCM using the key

➜ cargo run --bin ckms -- sym encrypt --tag my-key-file --output-file image.enc image.png
...
The encrypted file is available at "image.enc"

3. Decrypt the image.enc file using the key

➜ cargo run --bin ckms -- sym decrypt --tag my-key-file --output-file image2.png image.enc
...
The decrypted file is available at "image2.png"

See the documentation for more.

Repository content

The server is written in Rust and is broken down into several binaries:

• A server (cosmian_kms_server) which is the KMS itself
• A CLI (ckms) to interact with this server

And also some libraries:

• cosmian_kms_client to query the server
• cosmian_kmip which is an implementation of the KMIP standard
• cosmian_kms_pyo3 a KMS client in Python.

Please refer to the README of the inner directories to have more information.

Find the public documentation of the KMS in the documentation directory.

Building the KMS

OpenSSL v3.2.0 is required to build the KMS.

Linux or MacOS (CPU Intel or MacOs ARM)

Retrieve OpenSSL v3.2.0 (already build) with the following commands:

export OPENSSL_DIR=/usr/local/openssl
sudo mkdir -p ${OPENSSL_DIR}
sudo chown -R $USER ${OPENSSL_DIR}
bash .github/scripts/get_openssl_binaries.sh

Windows

1. Install Visual Studio Community with the C++ workload and clang support.

2. Install Strawberry Perl.

3. Install vcpkg following these instructions

4. Then install OpenSSL 3.2.0:

The files vcpkg.json and vcpkg_fips.json are provided in the repository to install OpenSSL v3.2.0:

vcpkg install --triplet x64-windows-static
vcpkg integrate install
$env:OPENSSL_DIR = "$env:VCPKG_INSTALLATION_ROOT\packages\openssl_x64-windows-static"

For a FIPS compliant build, use the following commands (in order to build fips.dll), run also:

Copy-Item -Path "vcpkg_fips.json" -Destination "vcpkg.json"
vcpkg install
vcpkg integrate install

Build the KMS

Once OpenSSL is installed, you can build the KMS. To avoid the additive feature issues, the main artifacts - the CLI, the KMS server and the PKCS11 provider - should directly be built using cargo build --release within their own crate, not from the project root.

Build the server and CLI binaries:

cd crate/server
cargo build --release
cd ../..
cd crate/ckms
cargo build --release

Build the Docker Ubuntu container

You can build a docker containing the KMS server as follows:

docker build . --network=host -t kms

Or:

# Example with FIPS support
docker build . --network=host \
               --build-arg FEATURES="--features=fips" \
               -t kms

Running the unit and integration tests

By default, tests are run using cargo test and an SQLCipher backend (called sqlite-enc). This can be influenced by setting the KMS_TEST_DB environment variable to

• sqlite, for plain SQLite
• mysql (requires a running MySQL or MariaDB server connected using a "mysql://kms:kms@localhost:3306/kms" URL)
• postgresql (requires a running PostgreSQL server connected using a "postgresql://kms:[email protected]:5432/kms"URL)
• redis-findex (requires a running Redis server connected using a "redis://localhost:6379" URL)

Example: testing with a plain SQLite and some logging

RUST_LOG="error,cosmian_kms_server=info,cosmian_kms_cli=info" KMS_TEST_DB=sqlite cargo test

Alternatively, when writing a test or running a test from your IDE, the following can be inserted at the top of the test:

unsafe {
set_var("RUST_LOG", "error,cosmian_kms_server=debug,cosmian_kms_cli=info");
set_var("RUST_BACKTRACE", "1");
set_var("KMS_TEST_DB", "redis-findex");
}
log_init(option_env!("RUST_LOG"));

Development: running the server with cargo

To run the server with cargo, you need to set the RUST_LOG environment variable to the desired log level and select the correct backend (which defaults to sqlite-enc).

RUST_LOG="info,cosmian_kms_server=debug" \
cargo run --bin cosmian_kms_server -- \
--database-type redis-findex --database-url redis://localhost:6379 \
--redis-master-password secret --redis-findex-label label

Setup as a Supervisor service

Supervisor (A Process Control System) is a client/server system that allows its users to monitor and control a number of processes on UNIX-like operating systems.

Concerning the KMS, copy the binary target/release/cosmian_kms_server to the remote machine folder according to cosmian_kms.ini statement (i.e.: /usr/sbin/cosmian_kms_server).

Copy the cosmian_kms.ini config file as /etc/supervisord.d/cosmian_kms.ini in the remote machine.

Run:

supervisorctl reload
supervisorctl start cosmian_kms
supervisorctl status cosmian_kms

Server parameters

If a configuration file is provided, parameters are set following this order:

• conf file (env variable COSMIAN_KMS_CONF set by default to /etc/cosmian_kms/kms.toml)
• default (set on struct)

Otherwise, the parameters are set following this order:

• args in the command line
• env var
• default (set on struct)

Use the KMS inside a Cosmian VM on SEV/TDX

See this README for more details about Cosmian VM.

To deploy the KMS inside a Cosmian VM, connect to the VM and follow these steps:

# Copy from resources/supervisor/cosmian_kms.ini
$ sudo vi /etc/supervisord.d/cosmian_kms.ini

# Copy the KMS server binary
$ sudo cp some_location/cosmian_kms_server /usr/sbin/cosmian_kms

# Create a conf file for the KMS (from resources/server.toml)
# Instead of using default path `/etc/cosmian_kms/server.toml`,
# we are using a path within LUKS encrypted container
$ sudo vi /var/lib/cosmian_vm/data/app.conf
$ sudo export COSMIAN_KMS_CONF="/var/lib/cosmian_vm/data/app.conf"
$ sudo supervisorctl reload
$ sudo supervisorctl start cosmian_kms

# Check logs
$ sudo tail -f /var/log/cosmian_kms.err.log
$ sudo tail -f /var/log/cosmian_kms.out.log

Now you can interact with your KMS through the KMS CLI.

You can also interact with the Cosmian VM Agent through its own CLI as follows:

# From your local machine
# Snapshot the VM (it could take a while)
$ ./cosmian_vm --url https://<DOMAIN_NAME>:<PORT> snapshot

# From time to time, verify it
$ ./cosmian_vm --url https://<DOMAIN_NAME>:<PORT> verify --snapshot ./cosmian_vm.snapshot
Reading the snapshot...
Fetching the collaterals...
[ OK ] Verifying TPM attestation
[ OK ] Verifying VM integrity (against N files)
[ OK ] Verifying TEE attestation

You can also provide the configuration file of the KMS through the Cosmian VM Agent and let it start the KMS.

1. Check that the /etc/supervisord.d/cosmian_kms.ini contains the following line: environment=COSMIAN_KMS_CONF=/var/lib/cosmian_vm/data/app.conf
2. Add the following lines in /etc/cosmian_vm/agent.toml

[app]
service_type = "supervisor"
service_app_name = "cosmian_kms"
app_storage = "data/"

3. Provide the configuration (where server.toml is the configuration file of the KMS):

$ ./cosmian_vm --url https://domain.name:port app init -c server.toml
Processing init of the deployed app...
The app has been configured

4. Save the printed key for further use
5. In case of reboot, you will need to restart the KMS manually by sending the configuration decryption key (the key saved at step 4):

./cosmian_vm --url https://domain.name:port app restart --key 378f1f1b3b5cc92ed576edba265cc91de6872d61c00b0e01dba6d0ea80520820

Releases

All releases can be found in the public URL package.cosmian.com.

Benchmarks

To run benchmarks, go to the crate/test_server directory and run:

cargo bench

Typical values for single-threaded HTTP KMIP 2.1 requests (zero network latency) are as follows

- RSA PKCSv1.5:
    - encrypt
            - 2048 bits: 128 microseconds
            - 4096 bits: 175 microseconds
    - decrypt
            - 2048 bits: 830 microseconds
            - 4096 bits: 4120 microseconds
- RSA PKCS OAEP:
    - encrypt
            - 2048 bits: 134 microseconds
            - 4096 bits: 173 microseconds
    - decrypt
            - 2048 bits: 849 microseconds
            - 4096 bits: 3823 microseconds
- RSA PKCS KEY WRP (AES):
    - encrypt
            - 2048 bits: 142 microseconds
            - 4096 bits: 198 microseconds
    - decrypt
            - 2048 bits: 824 microseconds
            - 4096 bits: 3768 microseconds
- RSA Keypair creation (saved in KMS DB)
    -  2048 bits: 33 milliseconds
    -  4096 bits: 322 milliseconds