Skip to main content

Ingress Nginx

CrowdSec

📚 Documentation 💠 Hub 💬 Discourse

A lua Remediation Component for Ingress Nginx Controller.

How does it work ?

This component leverages OpenResty lua's API, used the ingress nginx controller as a plugin.

Supported features:

  • Live mode (query the local API for each request)
  • Stream mode (pull the local API for new/old decisions every X seconds)
  • Ban remediation (can ban an IP address by redirecting him or returning a custom HTML page)
  • CAPTCHA remediation (can return a captcha)
  • Works with IPv4/IPv6
  • Support IP ranges (can apply a remediation on an IP range)

At the back, this component uses crowdsec lua lib.

Installation

Before installation

The Ingress nginx controller should be installed using the official helm chart

Using Helm

First you need to create new ingress-nginx chart values file (crowdsec-ingress-bouncer.yaml) to upgrade the ingress controller with the crowdsec plugin.

controller:
extraVolumes:
- name: crowdsec-bouncer-plugin
emptyDir: {}
extraInitContainers:
- name: init-clone-crowdsec-bouncer
image: crowdsecurity/lua-bouncer-plugin
imagePullPolicy: IfNotPresent
env:
- name: API_URL
value: "http://crowdsec-service.crowdsec.svc.cluster.local:8080" # crowdsec lapi service-name
- name: API_KEY
value: "<API KEY>" # generated with `cscli bouncers add -n <bouncer_name>
- name: BOUNCER_CONFIG
value: "/crowdsec/crowdsec-bouncer.conf"
- name: CAPTCHA_PROVIDER
value: "recaptcha" # valid providers are recaptcha, hcaptcha, turnstile
- name: SECRET_KEY
value: "<your-captcha-secret-key>" # If you want captcha support otherwise remove this ENV VAR
- name: SITE_KEY
value: "<your-captcha-site-key>" # If you want captcha support otherwise remove this ENV VAR
- name: BAN_TEMPLATE_PATH
value: /etc/nginx/lua/plugins/crowdsec/templates/ban.html
- name: CAPTCHA_TEMPLATE_PATH
value: /etc/nginx/lua/plugins/crowdsec/templates/captcha.html
command: ['sh', '-c', "sh /docker_start.sh; mkdir -p /lua_plugins/crowdsec/; cp -R /crowdsec/* /lua_plugins/crowdsec/"]
volumeMounts:
- name: crowdsec-bouncer-plugin
mountPath: /lua_plugins
extraVolumeMounts:
- name: crowdsec-bouncer-plugin
mountPath: /etc/nginx/lua/plugins/crowdsec
subPath: crowdsec
config:
plugins: "crowdsec"
lua-shared-dicts: "crowdsec_cache: 50m"
server-snippet : |
lua_ssl_trusted_certificate "/etc/ssl/certs/ca-certificates.crt"; # If you want captcha support otherwise remove this line
resolver local=on ipv6=off;

This values upgrade your ingress deployment to add crowdsec lua lib as a plugin and run with the ingress controller. It used this docker image to copy the crowdsec lua library.

Once you have this patch we can upgrade the ingress-nginx chart.

helm -n ingress-nginx upgrade -f ingress-nginx-values.yaml -f crowdsec-ingress-bouncer.yaml ingress-nginx ingress-nginx

And then check if the ingress controller is running well.

kubectl -n ingress-nginx get pods
info

In stream mode, the component will launch an internal timer to pull the local API at the first request made to the ingress controller.

Ingress controller Configuration

The component uses lua_shared_dict to share cache between all workers.

If you want to increase the cache size you need to change this value :

controller:
config:
lua-shared-dicts: "crowdsec_cache: 50m"

⚠️ Do not rename the crowdsec_cache shared dict, else the component will not work anymore.

When using captcha remediation

To make HTTP request in the component, we need to set a resolver in the configuration. We choose local=on directive since we query google.com for the captcha verification, but you can replace it with a valid one.

To make secure HTTP request in the component, we need to specify a trusted certificate (lua_ssl_trusted_certificate). You can also change this with a valid one :

  - /etc/ssl/certs/ca-certificates.crt (Debian/Ubuntu/Gentoo)
- /etc/pki/tls/certs/ca-bundle.crt (Fedora/RHEL 6)
- /etc/ssl/ca-bundle.pem (OpenSUSE)
- /etc/pki/tls/cacert.pem (OpenELEC)
- /etc/pki/ca-trust/extracted/pem/tls-ca-bundle.pem (CentOS/RHEL 7)
- /etc/ssl/cert.pem (OpenBSD, Alpine)

References

API_KEY

string

API_KEY=<API_KEY>

CrowdSec Local API key.

Generated with sudo cscli bouncers add command.

API_URL

string

API_URL=http://<ip>:<port>

CrowdSec local API URL.

BOUNCING_ON_TYPE

all | ban | captcha

BOUNCING_ON_TYPE=all

Type of remediation we want to bounce. If you choose ban only and receive a decision with captcha as remediation, the component will skip the decision.

FALLBACK_REMEDIATION

ban | captcha

FALLBACK_REMEDIATION=ban

The fallback remediation is applied if the component receives a decision with an unknown remediation.

MODE

stream | live

MODE=stream

The component mode:

  • stream: The component will pull new/old decisions from the local API every X seconds (UPDATE_FREQUENCY parameter).
  • live: The component will query the local API for each requests (if IP is not in cache) and will store the IP in cache for X seconds (CACHE_EXPIRATION parameter).
note

The timer that pull the local API will be triggered after the first request.

REQUEST_TIMEOUT

int

REQUEST_TIMEOUT=1000

Timeout in milliseconds for the HTTP requests done by the component to query CrowdSec local API or captcha provider (for the captcha verification).

EXCLUDE_LOCATION

string (comma separated)

EXCLUDE_LOCATION=/<path1>,/<path2>

The locations to exclude while bouncing. It is a list of location, separated by commas.

⚠️ It is not recommended to put EXCLUDE_LOCATION=/.

CACHE_EXPIRATION

int

This option is only for the live mode.

CACHE_EXPIRATION=120

The cache expiration, in second, for IPs that the component store in cache in live mode.

UPDATE_FREQUENCY

int

This option is only for the stream mode.

UPDATE_FREQUENCY=10

The frequency of update, in second, to pull new/old IPs from the CrowdSec local API.

REDIRECT_LOCATION

string

This option is only for the ban remediation.

REDIRECT_LOCATION=/<path>

The location to redirect the user when there is a ban.

If it is not set, the component will return the page defined in the BAN_TEMPLATE_PATH with the RET_CODE (403 by default).

BAN_TEMPLATE_PATH

string (path to file)

This option is only for the ban remediation.

BAN_TEMPLATE_PATH=<path_to_html_template>

The path to a HTML page to return to IPs that trigger ban remediation.

By default, the HTML template is located in /etc/nginx/lua/plugins/crowdsec/templates/ban.html.

RET_CODE

int

This option is only for the ban remediation.

RET_CODE=403

The HTTP code to return for IPs that trigger a ban remediation. If nothing specified, it will return a 403.

CAPTCHA_PROVIDER

recaptcha | hcaptcha | turnstile

This option is only for the captcha remediation.

CAPTCHA_PROVIDER=recaptcha
info

For backwards compatability reasons recaptcha is the default if no value is set.

SECRET_KEY

string

This option is only for the captcha remediation.

SECRET_KEY=<captcha_secret_key>

The captcha secret key.

SITE_KEY

string

This option is only for the captcha remediation.

SITE_KEY=<captcha_site_key>

The captcha site key.

CAPTCHA_TEMPLATE_PATH

string (path to file)

This option is only for the captcha remediation.

CAPTCHA_TEMPLATE_PATH=<path_to_html_template>

The path to a captcha HTML template.

The component will try to replace {{captcha_site_key}} in the template with SITE_KEY parameter.

By default, the HTML template is located in /etc/nginx/lua/plugins/crowdsec/templates/captcha.html.

CAPTCHA_EXPIRATION

int

This option is only for the captcha remediation.

CAPTCHA_EXPIRATION=3600

The time for which the captcha will be validated. After this duration, if the decision is still present in CrowdSec local API, the IPs address will get a captcha again.