How to secure a container

This page explains how to secure your container.

Before you start

To complete the actions presented below, you must have:

• A Scaleway account logged into the console
• Owner status or IAM permissions allowing you to perform actions in the intended Organization
• Created a containers namespace
• Deployed a container
• Created an authentication token for your container

Use secrets to store access keys and sensitive information

Instead of using environment variables (which are stored in clear text) for your containers, use secrets. These are pieces of information that can be used via environment variables, but are encrypted in storage.

Configure secrets from the Scaleway console

1. Click Containers in the Serverless section of the side menu. The containers page displays.
2. Click the relevant Containers namespace.
3. Click the name of the container for which you want to define secrets.
4. Click the Deployment tab.
5. Scroll to the Secrets section of the page and click Add secret. Enter the key and value for your secret. Repeat for additional secrets.
   Important

   Be careful when you type your secrets. You will not be able to read the value in the console once submitted.

6. Click Deploy container to submit your secrets and redeploy your container.

Configure secrets using the Serverless framework

Add secret to your container's description (more information in the plugin documentation). We recommend using them with global environment variables or a .env file stored independently (and kept secret).

secret:
      secret_1: ${env:SCW_SECRET_KEY}

Configure secrets using Terraform/OpenTofu

Add the following resource description in Terraform/OpenTofu:

secret_environment_variables = { "key" = "secret" }

Restrict access to your containers

You can set Serverless containers as private if you want, to protect them from unwanted or unauthorized calls.

Unauthenticated calls will be rejected, and your container will not be triggered. This feature is handy if an event triggers your container (CRON, NATS or Queues) or if you put them behind an API gateway or a proxy server (see examples in serverless-examples).

Restrict access from the Scaleway console

1. Click Containers in the Serverless section of the side menu. The containers page displays.
2. Click the relevant container namespace.
3. Click the name of the container for which you want to define secrets.
4. Click the Security tab.
5. Set the Privacy Policy of the container to Private.
6. If required, set up IAM authentication for your container.

Your container is now private, and requires an X-Auth-Token header to be called:

curl -H "X-Auth-Token: <YOUR_SECRET_KEY>" <YOUR_CONTAINER_ENDPOINT>

Restrict access using the Serverless framework

Set privacy: private in your container's description.

Your container is now private, and requires an X-Auth-Token header to be called:

curl -H "X-Auth-Token: <YOUR_SECRET_KEY>" <YOUR_CONTAINER_ENDPOINT>

Refer to the How to manage authentication for private containers documentation for more information.

Advanced access control with IAM conditions

When a container is set to Private, you can use Scaleway IAM policy conditions to define granular access rules using Common Expression Language (CEL): policy conditions documentation. These conditions use Common Expression Language (CEL) to evaluate requests based on attributes like IP address, time, or user-agent.

Restrict access by specific IP addresses

To ensure your container is only reachable from a specific office network or a trusted proxy, you can use the inIpRange() function.

Example expression:

inIpRange(request.ip, "198.51.100.0/24")

Result: Only requests originating from the 198.51.100.0/24 subnet are authorized.

Restrict access to specific user-agents

You can restrict calls to specific tools or internal clients by checking the request.user_agent attribute. This is useful for ensuring only authorized automation tools (like Terraform or a specific internal bot) can trigger the service.

Example expression:

request.user_agent.contains("InternalAdminTool/1.0")

Result: Only requests with a User-Agent header containing "InternalAdminTool/1.0" are permitted.

Restrict access to specific time windows

For sensitive workloads that should only be active during business hours or specific maintenance windows, you can use request.time.

Example expression (Working hours in Paris):

request.time.getDayOfWeek() != 0 && request.time.getDayOfWeek() != 6
&& request.time.getHours("Europe/Paris") >= 9
&& request.time.getHours("Europe/Paris") < 18

Result: Access is granted only Monday through Friday, between 9:00 AM and 6:00 PM Paris time.

Redirect HTTP to HTTPS

If you do not want to expose your container over HTTP, you can enable the HTTP to HTTPS redirection to ensure that all traffic follows a secure path.

Configure redirection using the Scaleway console

1. Click Containers in the Serverless section of the side menu of the Scaleway console. The Containers page displays.
2. Click the relevant Containers namespace.
3. Click the name of the container for which you want to enable the redirection.
4. Click the Security tab.
5. Toggle the HTTPS connections only switch to On.

Incoming HTTP traffic is now redirected to HTTPS.

Configure redirection using the Serverless framework

To redirect HTTP traffic to HTTPS using the Serverless Framework, add the httpOption: redirected option to your container's description.

Refer to our dedicated repository for more information on container configuration using the Serverless Framework.

Set up alerts in Observability Cockpit (upcoming feature)

Using Scaleway Observability Cockpit, a managed Grafana solution to which all your containers are connected, you can:

• Monitor your containers using the default dashboard or create custom ones.
• Set up notifications to be alerted in case of unexpected behavior.

Advanced access control with IAM conditions

When a container is set to Private, you can use Scaleway IAM policy conditions to define granular access rules. These conditions use Common Expression Language (CEL) to evaluate requests based on attributes like IP address, time, or user-agent.

Restrict access by specific IP addresses

To ensure your container is only reachable from a specific office network or a trusted proxy, you can use the inIpRange() function.

Example expression:

inIpRange(request.ip, "198.51.100.0/24")

Result: Only requests originating from the 198.51.100.0/24 subnet are authorized.

Restrict access to specific user-agents

You can restrict calls to specific tools or internal clients by checking the request.user_agent attribute. This is useful for ensuring only authorized automation tools (like Terraform or a specific internal bot) can trigger the service.

Example expression:

request.user_agent.contains("InternalAdminTool/1.0")

Result: Only requests with a User-Agent header containing "InternalAdminTool/1.0" are permitted.

Restrict access to specific time windows

For sensitive workloads that should only be active during business hours or specific maintenance windows, you can use request.time.

Example expression (Working hours in Paris):

request.time.getDayOfWeek() != 0 && request.time.getDayOfWeek() != 6
&& request.time.getHours("Europe/Paris") >= 9
&& request.time.getHours("Europe/Paris") < 18

Result: Access is granted only Monday through Friday, between 9:00 AM and 6:00 PM Paris time.