SSL Offloading for Secure AI API Gateways with F5 BIG-IP LTM

Question

Pulumi · Accepted Answer

SSL offloading is a process where SSL encryption and decryption of traffic is delegated to a dedicated device, such as an F5 BIG-IP Local Traffic Manager (LTM). This relieves your backend servers of the resource-intensive work of encrypting and decrypting SSL/TLS traffic, thus enabling them to focus on processing application requests efficiently. In a cloud environment, this would typically be done to secure communication to an API Gateway which then routes requests to the appropriate service.

While Pulumi does not have a dedicated high-level component for F5 BIG-IP, it does provide a provider for interacting with such devices if they are part of your infrastructure. In the cloud context, if you're hosting your API on a cloud provider like AWS, Azure or GCP, they have their own services that provide SSL offloading capabilities, such as AWS's API Gateway with ACM (AWS Certificate Manager), Azure's Application Gateway, or Google's Cloud Load Balancing.

In this guide, I will demonstrate how to use Pulumi to set up an Azure Application Gateway with SSL offloading. Azure Application Gateway is a web traffic load balancer that enables you to manage traffic to your web applications. It includes the Web Application Firewall (WAF) which provides protection to web applications from common web vulnerabilities and exploits.

Here is the Python program using Pulumi to create an Azure Application Gateway with SSL offloading:

```python
import pulumi
import pulumi_azure_native as azure_native

# Assume that the necessary networking resources like Virtual Network and Subnet are already set up.
# We'll be using a dummy values for Virtual Network and Subnet names.
vnet_name = 'my-vnet'
subnet_name = 'my-subnet'
resource_group_name = 'my-resource-group'

# SSL certificates need to be provided to enable SSL offloading. These would typically come from a secret store or disk.
# For this example, we're using a placeholder for the certificate data.
ssl_cert_data = 'BASE64-ENCODED-CERTIFICATE-DATA'
ssl_cert_password = 'CERTIFICATE-PASSWORD'

# Create the Application Gateway
app_gateway = azure_native.network.ApplicationGateway("appGateway",
    resource_group_name=resource_group_name,
    sku=azure_native.network.ApplicationGatewaySkuArgs(
        name='Standard_v2',
        tier='Standard_v2',
    ),
    gateway_ip_configurations=[azure_native.network.ApplicationGatewayIPConfigurationArgs(
        name='appGatewayIpConfig',
        subnet=azure_native.network.SubResourceArgs(
            id=f'/subscriptions/{pulumi.config.subscription}/resourceGroups/{resource_group_name}/providers/Microsoft.Network/virtualNetworks/{vnet_name}/subnets/{subnet_name}',
        ),
    )],
    ssl_certificates=[azure_native.network.ApplicationGatewaySslCertificateArgs(
        name='sslCertificate',
        data=ssl_cert_data,
        password=ssl_cert_password,
    )],
    http_listeners=[azure_native.network.ApplicationGatewayHttpListenerArgs(
        name='httpListener',
        frontend_ip_configuration=azure_native.network.SubResourceArgs(
            id=f'/subscriptions/{pulumi.config.subscription}/resourceGroups/{resource_group_name}/providers/Microsoft.Network/applicationGateways/{app_gateway.name}/frontendIpConfigurations/appGatewayFrontendIP',
        ),
        frontend_port=azure_native.network.SubResourceArgs(
            id=f'/subscriptions/{pulumi.config.subscription}/resourceGroups/{resource_group_name}/providers/Microsoft.Network/applicationGateways/{app_gateway.name}/frontendPorts/443',
        ),
        ssl_certificate=azure_native.network.SubResourceArgs(
            id=f'/subscriptions/{pulumi.config.subscription}/resourceGroups/{resource_group_name}/providers/Microsoft.Network/applicationGateways/{app_gateway.name}/sslCertificates/sslCertificate',
        ),
        protocol='Https',
    )],
    # Further configurations like backend pools, backend HTTP settings, rules, etc. need to be defined according to your requirements.
)

# Export the Application Gateway ID
pulumi.export('app_gateway_id', app_gateway.id)
```

In this code:

- We've created an `Application Gateway` resource with the necessary configurations for SSL offloading.
- A SKU for the Application Gateway is defined. In this example, `Standard_v2` is being used.
- The IP configuration is attached to a subnet where the Application Gateway will reside.
- An SSL certificate is provided. In a real setup, you’d obtain this certificate from your CA, store it securely (e.g., in Azure Key Vault), and reference it here.
- An HTTP listener is created that points to the Application Gateway’s frontend IP configuration, listens on port 443, and uses the SSL certificate for SSL offloading.
- The code assumes you have placeholder or real certificate data and password, as well as the necessary networking setup such as the Virtual Network (VNet) and Subnet.

Please make sure that, when you're using this program, you will replace placeholder values including `ssl_cert_data`, `ssl_cert_password`, `vnet_name`, `subnet_name`, and `resource_group_name` with actual values from your environment.

For further details on Azure Application Gateway via Pulumi, visit the [official documentation](https://www.pulumi.com/registry/packages/azure-native/api-docs/network/applicationgateway/).