Kiebitz Services

This repository contains Kiebitz's backend services:

• A storage service that stores encrypted user & operator settings and temporary data.
• An appointments service that stores encrypted appointment data.

tl;dr

We are showing a quick version here, full details below make sure you installed Golang in a current version >=1.16.

we need a Redis server:
docker run -d -p 6379:6379 redis

simply run

1. make to install
2. source .test-setup so tests create/setup necessary data
3. kiebitz admin keys setup to generate necessary keys will overwrite existing key files
4. kiebitz run all to run the development services

Then have a look and jump to the APIs

Dependencies

The Kiebitz backend services are written in Golang. Please install a recent version, preferably >=1.16.

If you're running MacOS and run into the readlink: illegal option -- f error, you can resolve it by installing coreutils: brew install coreutils and linking it to your bin: ln -s /usr/local/bin/greadlink /usr/local/bin/readlink. Restart your terminal afterwards.

By default, Kiebitz uses a Redis database to store data. Please make sure a Redis server is available. You can change the connection details in the settings/dev/001_default.yml settings file. The metering services (for statistics) also uses a Redis database by default and can be configured just like the main database. In addition, to generate TLS certificates (which is not always necessary) Kiebitz relies on the openssl CLI.

Installation

To build and install all services into your GOPATH, simply run

make

Basic Setup

Kiebitz needs cryptographic keys and some helper data to function correctly. All of these can be generated using the kiebitz command.

First things first: Kiebitz looks for settings in the path given by the KIEBITZ_SETTINGS environment variable. For development, settings are in the settings/dev subdirectory of the repository. To set up our development environment, we simply run

source .dev-setup

For the commands below we'll assume that KIEBITZ_SETTINGS points to the settings/dev directory.

Cryptographic Keys

Now, we need to generate various cryptographic keys for signing and encryption. To do this, we simply run

kiebitz admin keys setup

Warning: Running this command will overwrite existing key files, potentially rendering all your development data useless, so be careful.

This will generate two files in the Kiebitz settings directory, 002_admin.json and 003_appt.json. The former is only for administration purposes and should remain locked away. The latter is for use with the appointments server.

Optionally, you can encrypt the 002_admin.json file with a passphrase. The passphrase must be present in the KIEBITZ_PASSPHRASE environment variable, and has to be pretsent for the generation of the keys as well as every time the server starts. You can generate an encrypted key file with the -e switch like this:

kiebitz admin keys setup -e

Now we can generate mediator keys. To do this, we simply run

kiebitz admin keys mediator > data/secret-mediator-keys.json

This will create a JSON data structure with all necessary keys for the mediator. Please be aware that the provider keys are just copied from the 002_admin.json file generated before. These keys enable mediators to decrypt provider data.

For the next steps of the setup process we'll need a running backend, so let's start it via

kiebitz --level debug run all

That should start the appointments and storage services. Now we can tell the backend about the newly created mediator keys, which we do via

kiebitz admin mediators upload data/secret-mediator-keys.json

This will sign the public signing and encryption keys of the mediator with the root key and put the signed key material on the backend for publication. That's it! Now we should be able to go to the /mediator URL in the frontend, load our mediator key file and verify providers. Providers should be able to sign up, upload their data for verification and get tokens. Users should also be able to sign up and receive invitations.

ZIP Code Data

ZIP code data helps Kiebitz to estimate distances between zip code areas. There are two files data/distances.json and data/distances-areas.json that need to be uploaded. We can do this via

# upload distances for full ZIP codes (used when matching tokens to providers)
kiebitz admin distances upload data/distances.json
# upload distances for ZIP codes areas (used when filtering appointments for users)
kiebitz admin distances upload data/distances-areas.json

To generate the distances, we can use the make_distances.py and make_area_distances.py scripts from the .scripts folder (normally this is not necessary though):

python3 .scripts/make_distances.py
python3 .scripts/make_area_distances.py

Note: We can test the system without the ZIP code data, but tokens will then only be distributed to matching zip codes.

Signup Codes

We can also upload user & provider codes if we want to restrict who can register on the platform (this requires setting appointments.user_codes_enabled: true and appointments.provider_codes.enabled: true, respectively):

# upload user codes from a file
kiebitz admin codes upload data/secret-user-codes.json
# upload provider codes from a file
kiebitz admin codes upload data/secret-provider-codes.json

To generate codes, we simply run

# generate 10.000 user codes
kiebitz admin codes generate --actor user -n 10000 > data/secret-user-codes.json
# generate 10.000 provider codes
kiebitz admin codes generate --actor provider -n 10000 > data/secret-user-codes.json

Codes are just random 16 byte values, and the actor parameter just tells the backend for which actor the codes should be used.

TLS Certificates

Finally, if we want to run Kiebitz using a self-signed TLS certificate, we simply run

make certs

to generate these certificates, and then enable them by commenting out the tls section in the settings.

Running

Start redis:

docker run -d -p 6379:6379 redis

To run the development services we can then

# run the appointments service
kiebitz run appointments
# ...or run the storage service
kiebitz run storage
# ...or run all services
kiebitz run all

Logging

The logrus module is used for logging. The default log level is info. More verbose log levels are available, namely debug and trace. To run kiebitz at another log leve, simply pass the --level argument. E.g.

kiebitz --level trace run all

APIs

The Kiebitz services can be exposed as a JSON-RPC or REST service (or both). Simply set or remove the jsonrpc or rest section in the storage or appointments section of the settings to enable or disable the api for those servers.

For example, if both API types are enabled, the getAppointmentsByZipCode endpoint with parameters zipCode=10707 and radius=20 can be reached via both of the following queries:

# REST endpoint
curl http://localhost:8888/appointments/zipCode/10707/20
# JSON-RPC endpoint
curl -X POST --header "Content-Type: application/json" http://localhost:8888/jsonrpc --data '{"jsonrpc": "2.0", "method": "getAppointmentsByZipCode", "params": {"zipCode": "10707", "radius": "20"}}'

In general, the REST API is better for caching as it exposes cacheable endpoints via GET requests, while the JSON-RPC API provides a simpler and more natural interface.

Testing

Here's how you can send a request to the storage server via curl (this assumes you have jq installed for parsing of the JSON result):

curl --cacert settings/dev/certs/root.crt --resolve storage-1:9999:127.0.0.1 https://storage-1:9999/jsonrpc --header "Content-Type: application/json; charset=utf-8" --data '{"method": "getSettings", "id": "2", "params": {"key": "az4df7vjunsd6ad"}, "jsonrpc": "2.0"}' 2>/dev/null | jq

To run all Go tests and benchmarks, simply

# run normal tests
make test
# run race-condition tests
make test-races
# run benchmarks
make bench

Load Testing

Careful, the following commands will create massive amounts of fake data via the API client, never run this against the production system, except for initial load testing!

You can simulate providers, appointments and bookings in the backend using the testing benchmark command. The following command will create 1.000 providers with 1.000 appointments with 20 slots each, hence a total of 20.000.000 appointments:

kiebitz testing benchmark --providers 1000 --appointments 1000 --slots 20

This command will use the given settings and connect to a running API server, hence to run it you need to also run the Kiebitz API. Probably you want to use the test settings for this

Development

To auto-generate copyright headers for Golang files, simply run

make copyright

Security

Did you find a security issue you'd like to report? Please contact us at impftermin@inoeg.de. We appreciate if you follow responsible disclosure practices. Please do not create a public Github issue for exploitable vulnerabilities that you've identified. We do not have a formal bug bounty program in place but will try to reward researchers for significant security findings. We also pledge to never take any kind of legal action or retaliate against researchers that disclose security issues in good faith. You may of course disclose issues anonymously as well.