desec-stack
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Backbone of the deSEC.io Free Secure DNS Hosting Service
deSEC Stack
This is a docker-compose application providing the basic stack for deSEC name services. It consists of
-
nslord
: Eventually authoritative DNS server (PowerDNS). DNSSEC keying material is generated here. -
nsmaster
: Stealth authoritative DNS server (PowerDNS). Receives fully signed AXFR zone transfers fromnslord
. No access to keys. -
api
: RESTful API to create deSEC users and domains, see documentation. -
dbapi
,dblord
,dbmaster
: Postgres databases forapi
andnsmaster
, MariaDB database fornslord
, respectively. -
www
: nginx instance serving static web site content and proxying toapi
-
celery
: A shadow instance of theapi
code for performing asynchronous tasks (email delivery). -
rabbitmq
:celery
's queue -
memcached
:api
-wide in-memory cache, currently used to keep API throttling state -
openvpn-server
: OpenVPN server used to tunnel replication traffic between this stack and frontend DNS secondaries -
prometheus
: Prometheus server for monitoring
Requirements
Although most configuration is contained in this repository, some external dependencies need to be met before the application can be run. Dependencies are:
-
We run this software with the
--userland-proxy=false
flag of thedockerd
daemon, and recommend you do the same. -
Also, configure certificates for
openvpn-server
:- Get easy-rsa and follow this tutorial.
- Then, copy
ca.crt
,server.crt
, andserver.key
toopenvpn-server/secrets/
. - Create a preshared secret using
openvpn --genkey --secret ta.key
insideopenvpn-server/secrets/
.
For provisioning a secondary, use the same
easy-rsa
PKI and create a newclient.key
andclient.crt
pair. Transfer these securely onto the secondary, along withca.crt
andta.key
. (You can also create the key on the secondary and only transfer a certificate signing request and the certificate.) -
Set sensitive information and network topology using environment variables or an
.env
file. You need (you can use the.env.default
file as a template):- global
-
DESECSTACK_DOMAIN
: domain name under which the entire system will be running. The API will be reachable at https://desec.$DESECSTACK_DOMAIN/api/. For development setup, we recommend usingyourname.dedyn.io
-
DESECSTACK_NS
: the names of the authoritative name servers, i.e. names pointing to your secondary name servers. Minimum 2.
-
- network
-
DESECSTACK_IPV4_REAR_PREFIX16
: IPv4 net, size /16, for assignment of internal container IPv4 addresses. NOTE: If you change this in an existing setup, you need to manually update persisted data structures such as the MySQL grant tables! Better don't do it. -
DESECSTACK_IPV6_SUBNET
: IPv6 net, ideally /80 (see below) -
DESECSTACK_IPV6_ADDRESS
: IPv6 address of frontend container, ideally 0642:ac10:0080 in within the above subnet (see below) -
DESECSTACK_PORT_XFR
: Port over which XFRs are performed with secondaries
-
- certificates
-
DESECSTACK_WWW_CERTS
:./path/to/certificates
forwww
container. This directory is monitored for changes so that nginx can reload when new keys/certificates are provided. Note: The reload is done any time something changes in the directory. The relevant files are not watched individually.
-
- API-related
-
DESECSTACK_API_ADMIN
: white-space separated list of Django admin email addresses -
DESECSTACK_API_AUTHACTION_VALIDITY
: number of hours for which authenticated action links (e.g. email verification) should be considered valid (default: 0) -
DESECSTACK_API_DEBUG
: Django debug setting. Must be True (default indocker-compose.dev.yml
) or False (default otherwise) -
DESECSTACK_API_SEPA_CREDITOR_ID
: SEPA creditor ID for donations -
DESECSTACK_API_EMAIL_HOST
: when sending email, use this mail server -
DESECSTACK_API_EMAIL_HOST_USER
: username for sending email -
DESECSTACK_API_EMAIL_HOST_PASSWORD
: password for sending email -
DESECSTACK_API_EMAIL_PORT
: port for sending email -
DESECSTACK_API_SECRETKEY
: Django secret -
DESECSTACK_API_PSL_RESOLVER
: Resolver IP address to use for PSL lookups. If empty, the system's default resolver is used. -
DESECSTACK_DBAPI_PASSWORD_desec
: database password for desecapi -
DESECSTACK_MINIMUM_TTL_DEFAULT
: minimum TTL users can set for RRsets. The setting is per domain, and the default defined here is used on domain creation.
-
- nslord-related
-
DESECSTACK_DBLORD_PASSWORD_pdns
: mysql password for pdns on nslord -
DESECSTACK_NSLORD_APIKEY
: pdns API key on nslord -
DESECSTACK_NSLORD_CARBONSERVER
: pdnscarbon-server
setting on nslord (optional) -
DESECSTACK_NSLORD_CARBONOURNAME
: pdnscarbon-ourname
setting on nslord (optional) -
DESECSTACK_NSLORD_DEFAULT_TTL
: TTL to use by default, including for default NS records
-
- nsmaster-related
-
DESECSTACK_DBMASTER_PASSWORD_pdns
: mysql password for pdns on nsmaster -
DESECSTACK_NSMASTER_ALSO_NOTIFY
: Comma-separated list of additional IP addresses to notify of zone updates -
DESECSTACK_NSMASTER_APIKEY
: pdns API key on nsmaster (required so that we can execute zone deletions on nsmaster, which replicates to the secondaries) -
DESECSTACK_NSMASTER_CARBONSERVER
: pdnscarbon-server
setting on nsmaster (optional) -
DESECSTACK_NSMASTER_CARBONOURNAME
: pdnscarbon-ourname
setting on nsmaster (optional) -
DESECSTACK_NSMASTER_TSIGKEY
: Base64-encoded value of the default TSIG key used for talking to external secondaries (algorithm: HMAC-SHA256)
-
- monitoring-related
-
DESECSTACK_WATCHDOG_SECONDARIES
: space-separated list of secondary hostnames; used to check correct replication of recent DNS changes -
DESECSTACK_PROMETHEUS_PASSWORD
: basic auth password for userprometheus
athttps://${DESECSTACK_DOMAIN}/prometheus/
-
- global
How to Run
Development:
$ ./dev
Production:
$ docker-compose build && docker-compose up
Storage
All important data is stored in the databases managed by the db*
containers. They use Docker volumes which, by default, reside in /var/lib/docker/volumes/desec-stack_{dbapi_postgres,dblord_mysql,dbmaster_postgres}
.
This is the location you will want to back up. (Be sure to follow standard MySQL/Postgres backup practices, i.e. make sure things are consistent.)
API Versions and Roadmap
deSEC currently maintains the following API versions:
API Version | URL Prefix | Status | Support Ends |
---|---|---|---|
Version 1 | /api/v1/ |
stable | earliest 6 months after v2 is declared stable |
Version 2 | /api/v2/ |
unstable |
You can find our documentation for all API versions at https://desec.readthedocs.io/. (Select the version of interest in the navigation bar.)
Notes on IPv6
This stack is IPv6-capable. Caveats:
-
It is not necessary to start the Docker daemon with
--ipv6
or--fixed-cidr-v6
. However, it is recommended to rundockerd
with--userland-proxy=false
to avoid exposing ports on the host IPv6 address throughdocker-proxy
. -
Topology: Assuming 2a01:4f8:a0:12eb::/64 is the host network, and we reserve 2a01:4f8:a0:12eb:deec::/80 for the deSEC stack. Docker has more or less established that IPv6 addresses be composed of the /80 prefix and the container MAC address. We choose the private 06:42:ac MAC prefix, defining a /104 subnet. For the remaining 24 bits of the MAC and IPv6 address, the convention seems to be to use the last 24 bits from the internally assigned IPv4 address. However, the first 8 of these are configurable through the
DESECSTACK_IPV4_REAR_PREFIX16
variable. Since we don't want public IPv6 addresses to change if the internal IPv4 net prefix changes, we use0x10
for bits at position 24--17. We thus arrive at the subnet 2a01:4f8:a0:12eb:deec:642:ac10:0/108 for our public IPv6-enabled Docker containers. The last 16 bits of the IPv6 address we indeed take from the internally assigned IP address. The same procedure is used to set the MAC address of IPv6 containers (they begin with06:42:ac:10:
).All other traffic in the /80 subnet is unexpected and therefore rejected. This includes traffic for IPv6 addresses that Docker assigns. (If Docker uses the MAC address for this purpose, the prefix is 02:42:ac which is not part of our public network, so we're safe.)
Since the above topology is strictly determined by the /80 prefix and the MAC address, we hope that most of the hardcoding can be removed in the future.
-
Docker currently exposes IPv6-capable containers fully, without restriction. Therefore, it is necessary to set up a firewall, like (
ip6tables
)-A FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT -A FORWARD -d 2a01:4f8:a0:12eb:deec:642:ac10:0/108 -i eth0 -j ACCEPT -A FORWARD -d 2a01:4f8:a0:12eb:deec::/80 -i eth0 -j REJECT --reject-with icmp6-port-unreachable
Development: Getting Started Guide
As desec-stack utilizes a number of different technologies and software packages, it requires some effort to setup a stack ready for development. While there are certainly many ways to get started hacking desec-stack, here is one way to do it.
-
Requirements. This guide is intended and tested on Ubuntu 20.20. However, many other Linux distributions will also do fine. For desec-stack, docker and docker-compose are required. Further tools that are required to start hacking are git and curl. Recommended, but not strictly required for desec-stack development is to use certbot along with Let's Encrypt and PyCharm. jq, httpie, libmariadbclient-dev, libpq-dev, python3-dev (>= 3.8) and python3-venv (>= 3.8) are useful if you want to follow this guide. The webapp requires nodejs. To install everything you need for this guide except docker and docker-compose, use
sudo apt install certbot curl git httpie jq libmariadbclient-dev libpq-dev nodejs npm python3-dev python3-venv libmemcached-dev
-
Get the code. Clone this repository to your favorite location.
git clone [email protected]:desec-io/desec-stack.git
-
Obtain Domain Names. To run desec-stack, this guide uses a subdomain of dedyn.io provided by desec.io.
-
Register a deSEC user account. Check out the instructions in our documentation, in particular the Quickstart section.
-
Register a dedyn.io subdomain to run your desec-stack on it and set up the IP addresses. For this guide, we assume
example.dedyn.io
. Register it with:DOMAIN=example.dedyn.io http POST https://desec.io/api/v1/domains/ Authorization:"Token ${TOKEN}" name:='"'${DOMAIN}'"'
If you receive an answer that is different from status code 201, chances are that the name you chose is already taken by someone else. In that case, repeat the last step with a new name. To setup the necessary IP address records, we create a couple of A and AAAA records that point to localhost. As preparation, create a JSON file
dns.json
with the following content defining the DNS setup for desec-stack:[ {"type": "A", "ttl":300, "records": ["127.0.0.1"], "subname": "desec"}, {"type": "AAAA", "ttl":300, "records": ["::1"], "subname": "desec"}, {"type": "A", "ttl":300, "records": ["127.0.0.1"], "subname": "*.desec"}, {"type": "AAAA", "ttl":300, "records": ["::1"], "subname": "*.desec"}, {"type": "A", "ttl":300, "records": ["127.0.0.1"], "subname": "dedyn"}, {"type": "AAAA", "ttl":300, "records": ["::1"], "subname": "dedyn"}, {"type": "A", "ttl":300, "records": ["127.0.0.1"], "subname": "*.dedyn"}, {"type": "AAAA", "ttl":300, "records": ["::1"], "subname": "*.dedyn"} ]
We use the deSEC API to publish the DNS information as defined in
dns.json
:http POST https://desec.io/api/v1/domains/${DOMAIN}/rrsets/ Authorization:"Token ${TOKEN}" < dns.json
-
-
Obtain certificates. desec-stack requires SSL certificates for the above-mentioned
desec
anddedyn
hostnames as well as for various subdomains. (For a complete list, seewww/README.md
.) While we recommend to obtain signed certificates from Let's Encrypt, it's also possible to let desec-stack generate self-signed certificates on startup by just skipping this step. To use the deSEC certbot hook, first download it to an appropriate location and set up your credentials and domain name.mkdir -p ~/bin cd ~/bin curl https://raw.githubusercontent.com/desec-io/desec-certbot-hook/main/hook.sh > desec_certbot_hook.sh touch .dedynauth; chmod 600 .dedynauth echo DEDYN_TOKEN=${TOKEN} >> .dedynauth echo DEDYN_NAME=${DOMAIN} >> .dedynauth chmod +x desec_certbot_hook.sh
Now we use certbot to obtain certificates, using the DNS challenge for authentication.
certbot \ --config-dir certbot/config --logs-dir certbot/logs --work-dir certbot/work \ --manual --text --preferred-challenges dns \ --manual-auth-hook ~/bin/desec_certbot_hook.sh \ --manual-cleanup-hook ~/bin/desec_certbot_hook.sh \ --server https://acme-v02.api.letsencrypt.org/directory \ -d "*.${DOMAIN}" -d "update.dedyn.${DOMAIN}" -d "update4.dedyn.$DOMAIN" -d "update6.dedyn.$DOMAIN" \ -d "checkip.dedyn.${DOMAIN}" -d "checkipv4.dedyn.${DOMAIN}" -d "checkipv6.dedyn.${DOMAIN}" \ certonly
Note that the definition of config, logs and work dir are only necessary if you do not want to run certbot as root. Verifying the DNS challenge takes a while, so allow this command to take a couple of minutes. After successfully retrieving the certificate, you can find them in
certbot/config/live/$DOMAIN/
. To make them available to desec-stack (in the default location), we copy certificate and keys. In the project root directory,mkdir certs cd certs for SUBNAME in desec www.desec get.desec checkip.dedyn checkipv4.dedyn checkipv6.dedyn dedyn www.dedyn update.dedyn update6.dedyn do ln -s cer ${SUBNAME}.${DOMAIN}.cer ln -s key ${SUBNAME}.${DOMAIN}.key done cp ~/bin/certbot/config/live/${DOMAIN}/fullchain.pem cer cp ~/bin/certbot/config/live/${DOMAIN}/privkey.pem key
The last two steps need to be repeated whenever the certificates are renewed. While any location for the certificates is fine, the
certs/
folder is configured to be ignored by git so that private keys do not accidentally end up being committed. -
Configure desec-stack. As docker-compose application, desec-stack is configured by environment variables defined in the
.env
file in the project root directory. Because it contains sensitive information for each deployment,.env
is not part of the repository and ignored by git. However, we ship.env.default
and.env.dev
with templates for production and development, respectively..env.dev
is almost good enough for a basic development system, so let's use that as a basis:sed "s/^DESECSTACK_DOMAIN=.*/DESECSTACK_DOMAIN=${DOMAIN}/" .env.dev > .env
Optionally, edit the file and
- configure an email server host name, user name, and password to deliver emails can be included in
.env
. A convenient option is a MailTrap account. - adjust the network prefixes in
.env
to avoid collisions with other local networks.
Additionally, the VPN server for the replication network needs to be equipped with a pre-shared key (PSK) and a public key infrastructure (PKI). To generate the PSK, use the openvpn-server container:
docker-compose build openvpn-server && docker-compose run openvpn-server openvpn --genkey --secret /dev/stdout > openvpn-server/secrets/ta.key
To build the PKI, we recommend easy RSA. Please note that PKI instructions here are for development deployments only! Using this setup for production WILL DEFINITELY result in an INSECURE deployment! To make it available, clone the repository and link to the executable:
cd openvpn-server/secrets git clone https://github.com/OpenVPN/easy-rsa.git ln -s easy-rsa/easyrsa3/easyrsa
In order to create a new PKI,
./easyrsa init-pki ./easyrsa build-ca nopass
To make the new PKI's Certificate Authority available to the OpenVPN server,
ln -s pki/ca.crt
To issue a certificate for the OpenVPN server, generate a new key pair, a signing request, and sign the certificate.
./easyrsa gen-req server nopass ./easyrsa sign-req server server # requires interaction
Make the key and certificate available to OpenVPN server:
ln -s pki/issued/server.crt ln -s pki/private/server.key
As the setup of OpenVPN is completed, return to the project directory:
cd -
- configure an email server host name, user name, and password to deliver emails can be included in
-
Install webapp dependencies. To install the dependencies for the web site and GUI, run
cd webapp/ npm install cd -
-
Run desec-stack. To run desec-stack, use
./dev
If you run desec-stack for the first time, this will require a couple of downloads and take a while. Once it is up and running, you can query the API home endpoint:
http GET https://desec.${DOMAIN}/api/v1/
Congratulations, you have desec-stack up and running.
A convenient way to create a test user account is via
docker-compose exec api python3 manage.py shell -c 'from desecapi.models import User; User.objects.create_user(email="[email protected]", password="test1234");'
but users can also be created by signing up via the web GUI. The latter, however, requires that you can read email that is sent from your local setup. This can be achieved, e.g., by using mailtrap.io.
Of course, as this setup is only on your local machine, DNS information will not be published into the public DNS. However, the desec-stack nameserver is available on localhost port 5321. To check if desec-stack is working as expected, you can query the desec-stack nameserver locally for any information that you saved using your API.
[email protected] PASSWORD=insecure # Register account (https://desec.readthedocs.io/en/latest/quickstart.html). Hint: In dev mode, the captcha response contains the plaintext challenge. TOKEN=$(http POST https://desec.${DOMAIN}/api/v1/auth/login/ email:=\"${EMAIL}\" password:=\"${PASSWORD}\" | jq -r .token) http POST https://desec.${DOMAIN}/api/v1/domains/ Authorization:"Token ${TOKEN}" name:='"test.example"' http POST https://desec.${DOMAIN}/api/v1/domains/test.example/rrsets/ Authorization:"Token ${TOKEN}" type:=\"A\" ttl:=60 records:='["127.0.0.254"]'
After registering a user with your API, creating a domain and publishing some info to the DNS, use
dig @localhost -p 5321 test.example
to see if the nameserver is behaving as expected.
-
(Optional) Configure PyCharm for API Development. As a docker-compose application, desec-stack takes a while to start. Additionally, it is hard to connect a debugger to the docker containers. Our recommended solution is to develop the API using Django tests running outside the docker-compose application. This will dramatically decrease the time required for running the Django tests and enable just-in-time debugging in PyCharm. Also, it will enable you to browse dependencies code within PyCharm and thus ease debugging.
-
To get started, we create a virtual python environment that (to some extend) mimics the python environment in the docker container. In the project root,
cd api python3 -m venv venv source venv/bin/activate pip install wheel pip install -r requirements.txt
-
At this point, Django is ready to run in the virtual environment created above. There are two things to consider when running Django outside the container. First, the environment variables as defined in the
.env
file need to be made available in the shell. This can be done withset -a && source ../.env && set +a
Second, to make the tests run efficiently, a couple of settings are different from the production system: passwords are hashed using a fast (but insecure!) method, rate limits are switched off, and so on. To use the fast settings in your shell, run
export DJANGO_SETTINGS_MODULE=api.settings_quick_test
Third, the API needs a postgres database to run the tests. To serve as a test database, the
dbapi
container can be started using a test configuration which exposes the database at127.0.0.1
. In order to let Django know that the database is at127.0.0.1
instead of the usualdbapi
, set an additional environment variable:export DESECSTACK_DJANGO_TEST=1
Fourth, run the database:
docker-compose -f docker-compose.yml -f docker-compose.test-api.yml up -d dbapi
Finally, you can manage Django using the
manage.py
CLI. As an example, to run the tests, usepython3 manage.py test
-
Open the project root directory
desec-stack
in PyCharm and select File › Settings.- In Project: desec-stack › Project Structure, mark the
api/
folder as a source folder. - In Project: desec-stack › Project Interpreter, add a new interpreter. Choose "existing environment" and select
api/venv/bin/python3
from the project root. - In Languages & Frameworks › Django, enable the Django support and set the Django project root to
api/
.
- In Project: desec-stack › Project Structure, mark the
-
From the PyCharm menu, select Run › Edit Configurations and click on "Edit configuration templates"; select the "Django tests" template from the list.
- Open the Environment Variables dialog. Copy the contents of the
.env
file and paste it here. - Add an environment variable with the name
DESECSTACK_DJANGO_TEST
and the value1
. - Fill the Custom Settings field with the path to the
settings_quick_test
module. - At the bottom in the "Before launch" sections, add an "External tool" with the following settings:
- Name:
Postgres Test Container
- Program:
docker-compose
- Arguments:
-f docker-compose.yml -f docker-compose.test-api.yml up -d dbapi
- Name:
- Open the Environment Variables dialog. Copy the contents of the
-
To see if the test configuration is working, right click on the api folder in the project view and select Run Test. (Note that the first attempt may fail in case the
dbapi
container does not start up fast enough. In that case, just try again.) -
To use code inspection, click on Inspect Code… in PyCharm's Code menu and add a local custom scope with the following pattern:
file:api//*.py&&!file:api/venv//*&&!file:api/manage.py&&!file:api/api/wsgi.py&&!file:api/desecapi/migrations//*
From this point on, you are set up to use most of PyCharm's convenience features.
- For PyCharm's Python Console, the environment variables of your
.env
file andDJANGO_SETTINGS_MODULE=api.settings_quick_test
need to be configured in Settings › Build, Execution, Deployment › Console › Django Console. (Note that if you need to work with the database, you need to initialize it first by running all migrations; otherwise, the model tables will be missing from the database.)
-
Debugging
RabbitMQ
To access message queue information of RabbitMQ, use the RabbitMQ management plugin. First, port 15672 of the RabbitMQ
container needs to be exposed (default when using docker-compose.dev.yml
). Then, inside the container, create a user
that can access the RabbitMQ data:
rabbitmq-plugins enable rabbitmq_management
rabbitmqctl add_user admin admin
rabbitmqctl set_user_tags admin administrator
rabbitmqctl set_permissions admin '.*' '.*' '.*'
Then the web-based management interface will be available at http://localhost:15672 with user admin
and password
admin
.