The following text will be included as a change request to the Internet Engineering Task Force’s Cookies: HTTP State Management Mechanism document. The precise chapters to include this text are to be determined.
A new attribute titled tdl or terms-document-locator will be added to the
allowed attributes of the Set-Cookie syntax.
The purpose of the tdl label is to provide an immutable document that contains
the legal basis used to collect, store, use, and restrict the associated
cookie-value such that storage retrieval operations can utilize modifications
to Content Security Policy to determine if a storage read operation should be
allowed or denied.
The value provided as the tdl attribute must conform to the URI schema. (RFC
3986 which defined URI is already an informative reference). Any value that does
not conform to URI will be rejected and the operation will proceed as if the
tdl attribute had not been provided.
Set-Cookie operations will store the tdl value with the cookie-name and
cookie-value.
The following is an example of Set-Cookie operation that includes a TDL value.
Set-Cookie: SID=31d4d96e407aad42; TDL=https://ex.io/eu-ads-v1.html
TDL documents must be immutable and never change once published. They SHOULD contain a version component in their construction.
If the implementor detects a change to the content of the TDL document which does not relate to user preferences such as language, then the implementor SHOULD consider the TDL value to be unusable and reject it. This behavior encourages authors of TDL documents to exercise strict version controls.