Document updated on May 10, 2023

AWS SigV4 Authentication for Service-to-Service Calls

Use AWS SigV4 authentication in KrakenD when your backend services or APIs require signed AWS requests to authorize access. This method signs HTTP requests with AWS Signature Version 4, allowing KrakenD to securely authenticate to AWS services or custom APIs that understand SigV4 signed requests. You might need this component when:

• When accessing AWS APIs or services that enforce SigV4 signing (e.g., presign an S3 link).
• When your internal services require AWS IAM-based authentication for secure service-to-service communication.
• When you want KrakenD to handle AWS SigV4 signing transparently without external tooling.

This signing works with any Amazon HTTP service requiring SigV4.

Configuration of AWS SigV4

Configuring AWS SigV4 authentication involves specifying the service and region details in KrakenD’s backend extra_config while the authentication is external (see below). KrakenD will automatically sign requests using configured credentials and SigV4 protocol before forwarding to the backend.

{
  "url_pattern": "/",
  "extra_config": {
    "auth/aws-sigv4": {
        "service": "execute-api",
        "region": "us-east-1",
        "assume_role_arn": "arn:aws:sts::{account ID}:assumed-role/{resource}",
        "sts_region": "us-west-1"
    }
  }
}

The available properties are:

Authentication and connectivity

The KrakenD machine needs connectivity with your AWS account and the credentials to do so. There are several ways you can achieve this:

• Copying your AWS credentials in the default file, ~/.aws/credentials (and maybe an additional ~/.aws/config and the env var AWS_PROFILE if you have several profiles)
• Passing the environment variables with at least AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY (and maybe AWS_REGION) when starting KrakenD.
• Having an IAM user with a policy and execution role that lets you invoke the function from the machine

Authentication examples

Mounting an existing .aws directory with the credentials in it (notice that the home of the Docker user is krakend):

$docker run --rm -it -p "8080:8080" \
    -e "AWS_PROFILE=default" \
    -v "/home/user/.aws:/home/krakend/.aws:ro" \
    -v "$PWD:/etc/krakend" krakend/krakend-ee:2.11.0

Passing the credentials directly:

$docker run --rm -it -p "8080:8080" \
    -e "AWS_ACCESS_KEY_ID=XXX" \
    -e "AWS_SECRET_ACCESS_KEY=XXX" \
    -e "AWS_REGION=eu-west-1" \
    -v "$PWD:/etc/krakend" krakend/krakend-ee:2.11.0