signedRequestMode

Whether to enforce signed requests. The default value is DISABLED, which means all content is public, and does not authorize access. You must also set a signedRequestKeyset to enable signed requests. When set to REQUIRE_SIGNATURES, all matching requests will have their signature validated. Requests that were not signed with the corresponding private key, or that are otherwise invalid (expired, do not match the signature, IP address, or header) will be rejected with a HTTP 403 and (if enabled) logged. Possible values are: DISABLED, REQUIRE_SIGNATURES, REQUIRE_TOKENS.