crowdsec/docker

Quick reference

• Documentation and help: https://docs.crowdsec.net/
• Crowdsec concepts: https://docs.crowdsec.net/docs/concepts
• Where to file issues: https://github.com/crowdsecurity/crowdsec

What is Crowdsec

Crowdsec - An open-source, lightweight agent to detect and respond to bad behaviours. It also automatically benefits from our global community-wide IP reputation database.

How to use this image

Docker images available

crowdsec will use Alpine as default container. A debian container is also available with systemd for journalctl support. Simply add -debian to your tag to use this. Please be aware that debian containers are not available on all version, since the feature was implemented after the release of version 1.3.0

Required configuration

Journalctl (only for debian image)

To use journalctl (only for debian image) as log stream, eventually from the DSN environment variable, it's important that you mount the journal log from the host to the container it self. This can be done by adding the following volume mount to your docker command:

-v /var/log/journal:/run/log/journal

Logs ingestion and processing

Collections are a good place to start: https://docs.crowdsec.net/docs/collections/intro

Find collections|scenarios|parsers|postoverflows in the hub: https://hub.crowdsec.net

• Specify collections|scenarios|parsers/postoverflows to install via the environment variables (by default crowdsecurity/linux is installed)
• Mount volumes to specify your log files that should be ingested by crowdsec

Acquisition

/etc/crowdsec/acquis.yaml maps logs to provided parsers. Find out more here: https://docs.crowdsec.net/docs/concepts/#acquisition

acquis.yaml example:

filenames:
 - /logs/auth.log
 - /logs/syslog
labels:
  type: syslog
---
filename: /logs/apache2/*.log
labels:
  type: apache2

labels.type: use syslog if logs origin is syslog, checkout collection's documentation for the relevant type otherwise.

Recommended configuration

Volumes

We strongly suggest to mount named volumes for Crowdsec configuration and database to avoid credentials and decisions loss in case of container's destruction and recreation, version update, etc.

• Credentials and configuration: /etc/crowdsec
• Database when using default SQLite: /var/lib/crowdsec/data

Start a Crowdsec instance

docker run -d \
    -v local_path_to_crowdsec_config/acquis.yaml:/etc/crowdsec/acquis.yaml \
    -v crowdsec_config:/etc/crowdsec \
    -v crowdsec_data:/var/lib/crowdsec/data \
    -v /var/log/auth.log:/logs/auth.log:ro \
    -v /var/log/syslog.log:/logs/syslog.log:ro \
    -v /var/log/apache:/logs/apache:ro \
    -e COLLECTIONS="crowdsecurity/apache2 crowdsecurity/sshd" \
    -p 8080:8080 -p 6060:6060 \
    --name crowdsec crowdsecurity/crowdsec

... or docker-compose

Check this full stack example using docker-compose: https://github.com/crowdsecurity/example-docker-compose

How to extend this image

Full configuration

The container is built with specific docker configuration. If you need to change it, bind /etc/crowdsec/config.yaml to your local configuration file

Notifications

If you wish to use the notification system, you will need to mount at least a custom profiles.yaml and a notification configuration to /etc/crowdsec/notifications

Deployment use cases

Crowdsec is composed of an agent that parse logs and creates alerts that local API or LAPI tranform into decisions. Both can run in the same process but also on separated containers as it makes sense in complex configurations to have agents on the same machines as the protected component and a LAPI that gather all signals from agents and communicate with the central api.

Register a new agent with LAPI

docker exec -it crowdsec_lapi_container_name cscli machines add agent_user_name --password agent_password

Run an agent connected to LAPI

Add following environment variables to your docker run command:

• DISABLE_LOCAL_API=true
• AGENT_USERNAME="agent_user_name" - agent_user_name previously registred with LAPI
• AGENT_PASSWORD="agent_password" - agent_password previously registered with LAPI
• LOCAL_API_URL="http://LAPI_host:LAPI_port"

Next steps

Bouncers

Crowdsec being a detection component, remediation is implemented using bouncers. Each bouncer protect a specific component. Find out more:

https://hub.crowdsec.net/browse/#bouncers

https://docs.crowdsec.net/docs/user_guides/bouncers_configuration/

Automatic Bouncer Registration

You can automatically register bouncers with the crowdsec container on startup using environment variables or Docker secrets. You cannot use this process to update an existing bouncer without first deleting it.

To use environment variables, they should be in the format BOUNCER_KEY_<name>=<key>. e.g. BOUNCER_KEY_nginx=mysecretkey12345.

To use Docker secrets, the secret should be named bouncer_key_<name> with a content of <key>. e.g. bouncer_key_nginx with a content of mysecretkey12345.

A bouncer key can be any string but we recommend an alphanumeric value to keep consistent with crowdsec-generated keys and avoid problems with escaping special characters.

Console

We provide a web based interface to get more from Crowdsec: https://docs.crowdsec.net/docs/console

Subscribe here: https://app.crowdsec.net

Caveats

Using binds rather than named volumes (more explanation here) results in more complexity as you'll have to bind relevant files one by one where with named volumes you can mount full configuration and data folders. On the other hand, named volumes are less straightforward to navigate.

Reference

Environment Variables

• COLLECTIONS - Collections to install from the hub, separated by space : -e COLLECTIONS="crowdsecurity/linux crowdsecurity/apache2"
• SCENARIOS - Scenarios to install from the hub, separated by space : -e SCENARIOS="crowdsecurity/http-bad-user-agent crowdsecurity/http-xss-probing"
• PARSERS - Parsers to install from the hub, separated by space : -e PARSERS="crowdsecurity/http-logs crowdsecurity/modsecurity"
• POSTOVERFLOWS - Postoverflows to install from the hub, separated by space : -e POSTOVERFLOWS="crowdsecurity/cdn-whitelist"
• CONFIG_FILE - Configuration file (default: /etc/crowdsec/config.yaml) : -e CONFIG_FILE="<config_path>"
• DSN - Process a single source in time-machine : -e DSN="file:///var/log/toto.log" or -e DSN="cloudwatch:///your/group/path:stream_name?profile=dev&backlog=16h" or -e DSN="journalctl://filters=_SYSTEMD_UNIT=ssh.service"
• TYPE - Labels.type for file in time-machine : -e TYPE="<type>"
• TEST_MODE - Only test configs (default: false) : -e TEST_MODE="<true|false>"
• TZ - Set the timezone to ensure logs have a local timestamp.
• DISABLE_AGENT - Only test configs (default: false) : -e DISABLE_AGENT="<true|false>"
• DISABLE_LOCAL_API - Disable local API (default: false) : -e DISABLE_LOCAL_API="<true|false>"
• AGENT_USERNAME - Agent username (to register if is LAPI or to use if it's an agent) : -e AGENT_USERNAME="machine_id"
• AGENT_PASSWORD - Agent password (to register if is LAPI or to use if it's an agent) : -e AGENT_PASSWORD="machine_password"
• LOCAL_API_URL - To specify when an agent needs to connect to a LAPI crowdsec (To use only when DISABLE_LOCAL_API is set to true) : -e LOCAL_API_URL="http://lapi-address:8080"
• DISABLE_ONLINE_API - Disable Online API registration for signal sharing (default: false) : -e DISABLE_ONLINE_API="<true|false>"
• LEVEL_TRACE - Trace-level (VERY verbose) on stdout (default: false) : -e LEVEL_TRACE="<true|false>"
• LEVEL_DEBUG - Debug-level on stdout (default: false) : -e LEVEL_DEBUG="<true|false>"
• LEVEL_INFO - Info-level on stdout (default: false) : -e LEVEL_INFO="<true|false>"
• USE_TLS - Enable TLS on the API Server (default: false) : -e USE_TLS="<true|false>"
• CERT_FILE - TLS Certificate file (default: /etc/ssl/cert.pem) : -e CERT_FILE="<file_path>"
• KEY_FILE - TLS Key file (default: /etc/ssl/key.pem) : -e KEY_FILE="<file_path>"
• CUSTOM_HOSTNAME - Custom hostname for local api (default: localhost) : -e CUSTOM_HOSTNAME="<hostname>"
• DISABLE_COLLECTIONS - Collections to remove from the hub, separated by space : -e DISABLE_COLLECTIONS="crowdsecurity/linux crowdsecurity/nginx"
• DISABLE_PARSERS - Parsers to remove from the hub, separated by space : -e DISABLE_PARSERS="crowdsecurity/apache2-logs crowdsecurity/nginx-logs"
• DISABLE_SCENARIOS - Scenarios to remove from the hub, separated by space : -e DISABLE_SCENARIOS="crowdsecurity/http-bad-user-agent crowdsecurity/http-xss-probing"
• DISABLE_POSTOVERFLOWS - Postoverflows to remove from the hub, separated by space : -e DISABLE_POSTOVERFLOWS="crowdsecurity/cdn-whitelist crowdsecurity/seo-bots-whitelist"
• PLUGIN_DIR - Directory for plugins (default: /usr/local/lib/crowdsec/plugins/) : -e PLUGIN_DIR="<path>"
• BOUNCER_KEY_<name> - Register a bouncer with the name <name> and a key equal to the value of the environment variable.

Volumes

• /var/lib/crowdsec/data/ - Directory where all crowdsec data (Databases) is located

• /etc/crowdsec/ - Directory where all crowdsec configurations are located

File Locations

• /usr/local/bin/crowdsec - Crowdsec binary

• /usr/local/bin/cscli - Crowdsec CLI binary to interact with crowdsec

Find Us

• GitHub

Contributing

Please read contributing for details on our code of conduct, and the process for submitting pull requests to us.

License

This project is licensed under the MIT License - see the LICENSE file for details.