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Policies

Policies define the resources allowed on your applications through Content Security Policy (CSP) directives. Policies can log violations and also enforce an allowlist of resources, effectively blocking resources not included in the policies.

Policies can be one of the following:

  • Log policy: Defines allowed resources in log mode, without blocking any resources not covered by the policy. Analyze any policy violations to validate a new policy.
  • Allow policy: Defines allowed resources in enforce mode, blocking any resources not covered by the policy. Enable allow mode when you are sure your policy is correct and that it will not block essential application resources, which would affect your application’s end users. Allow policies will also log policy violations.

With allow policies you can create a positive security model, also known as positive blocking. According to this model, you define what is allowed and reject everything else. Such an approach helps you reduce the attack surface for unwanted third-party scripts in your application.

For details on the CSP directives Page Shield creates for each type of policy, refer to How Page Shield works. For more information on the format of CSP headers Page Shield adds to responses, refer to CSP HTTP header format.

​​ Next steps

Refer to the following pages for instructions on creating a policy in Page Shield: