Use URL lists to create policies

This page explains how to use URL lists to create and manage granular access policies for your outbound web traffic within your Secure Web Proxy instance. Instead of creating individual rules for every website, URL lists let you define a reusable, centralized collection of domains, hostnames, and specific URL patterns.

Here are a few key benefits of using URL lists:

  • Simplify policy management: you can apply a large set of allow or deny rules with a single reference in your security policy.

  • Enforce precise control: you can use specific syntax to match entire domains, subdomains, or exact URL paths. This helps ensure that your workloads can access only authorized destinations.

  • Secure web access: you can efficiently secure and audit web access across your Google Cloud environment.

Before you begin

  • Complete the initial setup steps.

  • Verify that you have the Google Cloud CLI version 406.0.0 or later installed:

    gcloud version | head -n1
    

    If you have an earlier gcloud CLI version installed, update the version:

    gcloud components update --version=406.0.0
    

Create a Secure Web Proxy instance with an empty policy

To create a Secure Web Proxy instance, you must first create an empty security policy and then create a web proxy that uses the policy.

Create an empty security policy

Console

  1. In the Google Cloud console, go to the SWP Policies page.

    Go to SWP Policies

  2. Click Create a policy.

  3. In the Name field, enter a name for the policy, such as myswppolicy.

  4. In the Description field, enter a description for the policy, such as My new swp policy.

  5. For Regions, select the region where you want to create the policy, such as us-central1.

  6. Click Create.

Cloud Shell

  1. Use your preferred text editor to create a policy.yaml file.

  2. Add the following to the policy.yaml file that you created:

    name: projects/PROJECT_NAME/locations/REGION/gatewaySecurityPolicies/POLICY_NAME
    description: POLICY_DESCRIPTION
    

    Replace the following:

    • PROJECT_NAME: name of your project

    • REGION: region where your policy is created, such as us-central1

    • POLICY_NAME: name of your policy

    • POLICY_DESCRIPTION: description for your policy

  3. Import the security policy by using the gcloud network-security gateway-security-policies import command:

    gcloud network-security gateway-security-policies import POLICY_NAME \
        --source=POLICY_FILE.yaml \
        --location=REGION
    

Create a web proxy

Console

  1. In the Google Cloud console, go to the Web Proxies page.

    Go to Web Proxies

  2. Click Create a secure web proxy.

  3. In the Name field, enter a name for the web proxy, such as myswp.

  4. In the Description field, enter a description for the web proxy, such as My new swp.

  5. For Routing mode, select the Explicit option.

  6. For Regions, select the region where you want to create the web proxy, such as us-central1.

  7. For Network, select the network where you want to create the web proxy.

  8. For Subnetwork, select the VPC subnet that you previously created as part of the initial setup steps.

  9. Optional: In the Web proxy IP address field, enter the Secure Web Proxy IP address.

    You can enter an IP address from the range of Secure Web Proxy IP addresses that reside in the subnetwork you created in the previous step. If you don't enter the IP address, then your Secure Web Proxy instance automatically chooses an IP address from the selected subnetwork.

  10. For Certificate, select the certificate that you want to use to create the web proxy.

  11. For Policy, select the policy that you created to associate the web proxy with.

  12. Click Create.

Cloud Shell

  1. Use your preferred text editor to create a gateway.yaml file.

  2. Add the following to the gateway.yaml file:

    name: projects/PROJECT_NAME/locations/REGION/gateways/GATEWAY_NAME
    type: SECURE_WEB_GATEWAY
    ports: [GATEWAY_PORT_NUMBERS]
    certificateUrls: [CERTIFICATE_URLS]
    gatewaySecurityPolicy: projects/PROJECT_NAME/locations/REGION/gatewaySecurityPolicies/POLICY_NAME
    network: projects/PROJECT_NAME/global/networks/NETWORK_NAME
    subnetwork: projects/PROJECT_NAME/regions/REGION/subnetworks/SUBNETWORK
    addresses: [GATEWAY_IP_ADDRESS]
    scope: samplescope
    

    Replace the following:

    • GATEWAY_NAME: name of this Secure Web Proxy instance

    • GATEWAY_PORT_NUMBERS: list of port numbers for this gateway, such as [80,443]

    • CERTIFICATE_URLS: list of SSL certificate URLs

    • SUBNETWORK: VPC subnet that you previously created as part of the initial setup steps

    • GATEWAY_IP_ADDRESS: optional list of IP addresses for your Secure Web Proxy instances within the proxy subnets that you previously created in the initial setup steps

      If you choose not to list IP addresses, omit the field to let the web proxy choose an IP address for you.

  3. Create the Secure Web Proxy instance by using the gcloud network-services gateways import command:

    gcloud network-services gateways import GATEWAY_NAME \
        --source=gateway.yaml \
        --location=REGION
    

Test connectivity

To test connectivity, use the curl command from any virtual machine (VM) instance within your Virtual Private Cloud (VPC) network:

  curl -x https://GATEWAY_IP_ADDRESS:PORT_NUMBER https://www.example.com --proxy-insecure

If everything is working correctly, then your Secure Web Proxy instance returns a 403 Forbidden status code. This error confirms the following:

  • The Secure Web Proxy instance has been successfully deployed and is actively receiving traffic.

  • The Secure Web Proxy policy is correctly enforcing the default security posture of rejecting all traffic until you define specific allow rules in the next sections.

Create and configure a URL list

Console

  1. In the Google Cloud console, go to the URL Lists page.

    Go to URL Lists

  2. Click Create a URL list. The Create URL list page opens.

  3. In the Name field, enter a name for the URL list, such as example-org-allowed-list.

  4. In the Description field, enter a description for the URL list, such as My new URL list.

  5. For Regions, select the region where you want to create the URL list, such as us-central1.

  6. To add the list of hosts, URLs, or patterns to match, in the URL list field, either enter the details or click Upload list to upload a custom list of URLs. For more information, see UrlList syntax reference.

  7. Click Create.

Cloud Shell

  1. Use your preferred text editor to create the url_list.yaml file.

  2. Add the following to the url_list.yaml file:

      name: projects/PROJECT_ID/locations/REGION/urlLists/URL_LIST_NAME
      values: URL_LIST
    

    Replace the following:

    • PROJECT_ID: unique ID of your Google Cloud project

    • REGION: region where your URL list is created, such as us-central1

    • URL_LIST_NAME: name of the URL list

    • URL_LIST: list of hosts, URLs, or patterns to match

    For more information, see UrlList syntax reference.

    The following is an example of a URL list rule file:

    name: projects/PROJECT_ID/locations/REGION/urlLists/example-org-allowed-list
    values:
      - www.example.com
      - about.example.com
      - "*.google.com"
      - "github.com/example-org/*"
    

    The asterisk (*) character has a special meaning in YAML. You must add quotation marks around URLs that include an * character.

  3. Import the URL list that you created by using the gcloud network-security url-lists import command so that your Secure Web Proxy rule can reference it.

    gcloud network-security url-lists import URL_LIST_NAME \
        --location=REGION \
        --project=PROJECT_ID \
        --source=url_list.yaml
    

Add a Secure Web Proxy rule

Console

  1. In the Google Cloud console, go to the SWP Policies page.

    Go to SWP Policies

  2. Click the name of your policy, such as myswppolicy.

  3. Click Add rule.

  4. For each rule, do the following:

    1. For Priority, enter a numeric evaluation order for the rule. Rules are evaluated from highest to lowest priority, where 0 is the highest priority.

    2. In the Name field, enter a name for the rule, such as allow-org-url-list.

    3. In the Description field, enter a description for the rule.

    4. For Action, select one of the following options:

      • Allow: to allow connection requests that match the rule.
      • Deny: to deny connection requests that match the rule.
    5. For the Status field, select one of the following options for the rule enforcement:

      • Enabled: to enforce the rule on your Secure Web Proxy instance.
      • Disabled: to not enforce the rule on your Secure Web Proxy instance.
    6. In the Session Match section, specify the unique name of the URL list that you created in the previous section. For example:

        sessionMatcher: "inUrlList(host(), 'projects/PROJECT_ID/locations/REGION/urlLists/URL_LIST_NAME)"
      

      For more information about the syntax for SessionMatcher, see CEL matcher language reference.

    7. In the Application Match section, specify the criteria for matching the request.

    8. Click Add rule.

Cloud Shell

  1. Use your preferred text editor to create a rule.yaml file.

  2. Add the following to the rule.yaml file:

    name: projects/PROJECT_ID/locations/REGION/gatewaySecurityPolicies/POLICY_NAME/rules/RULE_NAME
    basicProfile: ALLOW
    enabled: true
    priority: RULE_PRIORITY
    description: RULE_DESCRIPTION
    sessionMatcher: SESSION_CEL_EXPRESSION
    applicationMatcher: APPLICATION_CEL_EXPRESSION
    

    Replace the following:

    • PROJECT_ID: unique ID of your Google Cloud project

    • REGION: region that this rule applies to

    • POLICY_NAME: name of an existing security policy that your Secure Web Proxy instance uses

    • RULE_NAME: name of the rule

    • PRIORITY_VALUE: priority of the rule; a lower number corresponds to a higher priority

    • RULE_DESCRIPTION: description for the rule

    • SESSION_CEL_EXPRESSION: a Common Expression Language (CEL) expression. For more information, see CEL matcher language reference.

    • APPLICATION_CEL_EXPRESSION: a CEL expression for your application

    The following is an example of a rule file:

    name: projects/PROJECT_ID/locations/REGION/urlLists/allow-repos
    basicProfile: ALLOW
    enabled: true
    priority: 100
    description: Allow access to our list of known code repos.
    sessionMatcher: "inUrlList(host(), 'projects/PROJECT_ID/locations/REGION/urlLists/URL_LIST_NAME')"
    

  3. Import the rule that you created by using the gcloud network-security gateway-security-policies rules import command.

        gcloud network-security gateway-security-policies rules import RULE_NAME \
          --location=REGION \
          --project=PROJECT_ID \
          --source=rule.yaml \
          --gateway-security-policy=POLICY_NAME
    

Test the policy configuration

You can test connectivity again to validate that the URL list-based access rules are correctly configured and actively enforced by your Secure Web Proxy instance.

To test connectivity, use the following curl command:

curl -x https://SWP_IP_ADDRESS:SWP_PORT_NUMBER HTTP_TEST_ADDRESS
--proxy-insecure

Replace the following:

  • SWP_IP_ADDRESS: IP address of your Secure Web Proxy instance

  • SWP_PORT_NUMBER: port number of your web proxy, such as 443

  • HTTP_TEST_ADDRESS: an address to test, such as https://www.example.com. It matches a host or URL entry in your url_list.

If everything works correctly, then you receive a 200 OK response. This response confirms that the outbound traffic to a URL that's listed in your URL list and referenced by the security policy rule is successfully allowed through your Secure Web Proxy instance.

What's next