compute site-for-cookies from ancestor chain of a Frame - #3293
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The same logic should be applied to document.getCookies and Workers then?
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Can be merged once the comments are corrected.
| is_navigation: bool = true, | ||
| prefix: ?[]const u8 = null, | ||
| origin_url: ?[:0]const u8 = null, | ||
| // null means there is no initiating document (a browser-initiated |
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but browser-initiated requests do pass a cookie_origin . This comment seems wrong then? So now I'm curious when it is/should be null?
| const origin_url = origin_url_ orelse return true; | ||
| const origin_host = URL.getHostname(origin_url); | ||
| pub fn areSameSite(maybe_origin_url: ?SiteForCookies, target_host: []const u8) bool { | ||
| // No initiating document (browser-initiated request). |
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Repeats a (I think wrong) comment
| // .none is the site-for-cookies of a frame whose ancestor chain contains | ||
| // a cross-site document. Even though the target here is the cookies' own | ||
| // site, the request is cross-site: Strict is withheld. (Lax still rides | ||
| // navigations; whether a subframe load should count as one is #240.) |
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Took me a bit to find the #240 reference. I don't think a bare hashtag to a different project is useful.
The site for cookies were computed from the immediate parent `Frame`, which would allow sending a cookie that's `SameSite=Strict` from 2 levels deep under. Directly from RFC6265bis, this PR essentially implements (except for step 4, we skip host-less ancestors):
Given a Document (document), the following algorithm returns its
"site for cookies":
1. Let top-document be the active document in document's navigable's
top-level traversable.
2. Let top-origin be the origin of top-document's URI if top-
document's sandboxed origin browsing context flag is set, and
top-document's origin otherwise.
3. Let documents be a list consisting of the active documents of
document's inclusive ancestor navigables.
4. For each item in documents:
1. Let origin be the origin of item's URI if item's sandboxed
origin browsing context flag is set, and item's origin
otherwise.
2. If origin is not same-site with top-origin, return an origin
set to an opaque origin.
5. Return top-origin.
Also updates matchCookies/onCookieChanged from the hard-coded "same-site + navigation" to areSameSite(exec.siteForCookies(), host) and is_navigation=false.
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The site-for-cookies were computed from the immediate parent
Frame, which allow sending a cookie that'sSameSite=Strictfrom 2 levels deep under. Directly from RFC6265bis, this PR essentially implements (except for step 4, we skip host-less ancestors):Given a Document (document), the following algorithm returns its
"site for cookies":
Let top-document be the active document in document's navigable's
top-level traversable.
Let top-origin be the origin of top-document's URI if top-
document's sandboxed origin browsing context flag is set, and
top-document's origin otherwise.
Let documents be a list consisting of the active documents of
document's inclusive ancestor navigables.
For each item in documents:
Let origin be the origin of item's URI if item's sandboxed
origin browsing context flag is set, and item's origin
otherwise.
If origin is not same-site with top-origin, return an origin
set to an opaque origin.
Return top-origin.