LGTM2 actually.. On Mon, Mar 18, 2024 at 7:40 AM Yoav Weiss (@Shopify) < yoavwe...@chromium.org> wrote:
> LGTM1 to ship the ID assertion endpoint CORS requirements. > > On Wed, Mar 13, 2024 at 3:11 PM Nicolás Peña <n...@chromium.org> wrote: > >> >> On Wednesday, March 13, 2024 at 7:37:29 AM UTC-4 Yoav Weiss wrote: >> >> On Tuesday, March 12, 2024 at 3:11:24 PM UTC-4 Nicolás Peña wrote: >> >> Regarding risk: we are going to implement this and test the IDPs we know >> are currently using FedCM, but we do not anticipate them to break since >> they are currently already relying on using third-party cookies in iframes. >> We also plan to have developer outreach/blogpost for this change so >> developers currently testing out FedCM are not caught by surprise. >> >> Regarding vendor alignment: we have been working with Firefox and Apple >> to align on the correct behavior of the FedCM fetches: see >> https://github.com/fedidcg/FedCM/issues/320 and >> https://github.com/fedidcg/FedCM/issues/428. This I2S is a result of a >> lot of discussions, and the small addition was a result of a very recent >> discussion occurring on our FedCM CORS breakout session >> <https://www.w3.org/2024/03/breakouts-day-2024/#b-15220813-651d-4795-98ae-a17434c1e50f> >> . >> >> Regarding spec, during our breakout Anne also mentioned that the small >> addition is not possible to specify properly, as it depends on the ongoing >> cookie layering work. I will add a note >> <https://github.com/fedidcg/FedCM/pull/550> on the spec in that fetch so >> IDPs know which cookies should be sent. >> >> Anyways, I understand it is a bit late to add something to this I2S so if >> you prefer that we send a separate I2S/PSA for the SameSite change, we can >> do that instead. >> >> >> Is the accounts endpoint the same endpoint to which this intent applies? >> Or is it different from the ID assertion endpoint? >> If it's different, a separate I2S would be best. If it's the same, then I >> think we can probably fold it into this intent. >> >> >> This change is to the ID assertion endpoint, which is different from the >> accounts endpoint. Then based on your comment, we will keep those two in >> separate intents. Consider the small addition I suggested above removed. >> >> >> >> >> >> >> On Tuesday, March 12, 2024 at 1:34:56 PM UTC-4 Mike Taylor wrote: >> >> On 3/12/24 11:33 AM, Nicolás Peña Moreno wrote: >> >> Thanks for the suggestion, Yoav! It seems something fetch experts have >> some concerns about, so we do not plan to proceed with that suggestion at >> the moment. >> >> Thanks for considering! Anne makes a good point that active defense here >> (by filtering requests based on destination) would work better against >> timing attacks than passive defense (where the responses are blocked by the >> browser). Please make sure that IDPs are aware of the destination filtering >> requirement, by having it emphasized in developer facing documentation. >> >> >> Yes, we will work with devrel to continue ensuring IDP best practices are >> easily discoverable. >> >> >> >> I'd like to append a small addition to this I2S (mainly to avoid having >> an additional PSA since it is very related to this one): we would also like >> approval to only send Same-Site=None cookies in the accounts endpoint, >> instead of all cookies (so not Same-Site=Lax or Same-Site=Strict). This is >> also a breaking change but we do not anticipate IDPs to break, and also >> plan to work with them to ensure that they are aware of this change and are >> not caught by surprise. >> >> To my non-FedCM expert brain, this doesn't feel like a small addition >> (happy to be wrong!), beyond not understanding the scale of the risk, the >> normal process questions come to mind i.e., is it specced, do we have >> tests, what do other vendors think about it? >> >> >> On Monday, March 11, 2024 at 6:39:14 AM UTC-4 Yoav Weiss wrote: >> >> <owner hat off> >> I left a comment >> <https://github.com/fedidcg/FedCM/issues/428#issuecomment-1980469172> around >> potentially adding a CORS mode that would help IDP servers statically >> protect themselves from destination-change attacks. I don't *think* it's a >> blocker, but it's worth considering something along those lines to increase >> the solution's robustness to configuration errors, and ensure it fails >> closed. (and ask IDPs' security teams about their thoughts) >> >> On Wed, Mar 6, 2024 at 5:51 PM Nicolás Peña <n...@chromium.org> wrote: >> >> No, Sec-Fetch-Dest >> <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Sec-Fetch-Dest> >> is not changing. Sec-Fetch-Mode >> <https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Sec-Fetch-Mode> >> is. >> >> On Wednesday, March 6, 2024 at 11:31:35 AM UTC-5 Chris Harrelson wrote: >> >> On Wed, Mar 6, 2024 at 8:28 AM Nicolás Peña <n...@chromium.org> wrote: >> >> >> >> On Wednesday, March 6, 2024 at 5:11:09 AM UTC-5 Yoav Weiss wrote: >> >> On Wed, Mar 6, 2024 at 10:21 AM Yoav Weiss (@Shopify) < >> yoav...@chromium.org> wrote: >> >> >> >> On Mon, Mar 4, 2024 at 9:36 PM Mike Taylor <mike...@chromium.org> wrote: >> >> LGTM1 >> On 3/4/24 1:33 PM, Nicolás Peña wrote: >> >> Contact emails >> >> n...@chromium.org >> >> Explainer >> >> https://github.com/fedidcg/FedCM/issues/428 >> >> >> A few lines summarizing this issue would be most useful when evaluating >> this and understanding what y'all want to ship. >> In particular, it'd be useful to understand the request flow, what is the >> request's origin (as IIUC, we're talking about requests issued from the >> browser), and what is the request destination that we may want IDPs to >> check. >> >> Examples of the checks IDPs would have to make would also be helpful. >> >> >> Sure! From the spec >> <https://fedidcg.github.io/FedCM/#idp-api-id-assertion-endpoint>, here >> is a sample request: >> >> POST /fedcm_assertion_endpoint HTTP/1.1 >> Host: idp.example >> Origin: https://rp.example/ >> Content-Type: application/x-www-form-urlencoded >> Cookie: 0x23223 >> Sec-Fetch-Dest: webidentity >> account_id=123&client_id=client1234&nonce=Ct60bD&disclosure_ >> text_shown=true >> >> With this change, Sec-Fetch-Mode will now be cors in this request and the >> IDP is expected to return the following in the response (no preflight is >> performed): >> >> >> Do you mean Sec-Fetch-Dest? >> >> >> >> Access-Control-Allow-Origin: https://rp.example/ >> Access-Control-Allow-Credentials: true >> >> >> >> Also, is the "identity assertion" endpoint the same as the token endpoint >> <https://github.com/fedidcg/FedCM/blob/main/explainer.md#token_endpoint>? >> >> >> Yea. I think that explainer doc is not super up to date. >> >> >> >> Specification >> >> https://github.com/fedidcg/FedCM/pull/547 >> >> Summary >> >> The fetches in the FedCM API are hard to reason about because of the >> properties required of them. While there is ongoing discussion regarding >> the accounts endpoint, there is broad consensus that the ID assertion >> endpoint should use CORS. This aligns security properties of this fetch >> more closely to other fetches in the web platform. >> >> Blink component >> >> Blink>Identity>FedCM >> <https://g-issues.chromium.org/issues?q=status:open%20componentid:1456331&pli=1&authuser=0> >> >> TAG review >> >> Not requesting a TAG review. We have already had extensive discussions >> with Fetch experts. >> >> TAG review status >> >> N/A >> >> Risks >> >> Interoperability and Compatibility >> >> This is a backwards incompatible feature, but one that is warranted due >> to consensus reached by our security reviewers as well as other browser >> vendor engineers. We have a manageable list of IDPs that we know are using >> the FedCM API and we have reached out to all IDPs that are currently >> deploying FedCM to make sure that they won’t break with this change. >> >> >> Gecko: Positive based on TPAC discussions and https://github.com/fedidcg/ >> FedCM/issues/428. Not filing a standards position request for small >> additions at the explicit request from Firefox (they prefer PRs). >> >> WebKit: Positive based on TPAC discussions and >> https://github.com/fedidcg/FedCM/issues/428. Recently, standards >> position requests for smaller FedCM features have been closed, pointing to >> the (unresolved) main FedCM one in https://github.com/WebKit/stan >> dards-positions/issues/309 so not filing one for this. >> >> Web developers: No signals >> >> Other signals: >> >> Ergonomics >> >> N/A >> >> >> Activation >> >> N/A >> >> >> Security >> >> By adding CORS, we add a check that the IDP explicitly agrees for the >> browser to share the ID assertion response to the RP. In addition, having >> this fetch align with most other credentialed fetches in the browser means >> that any future protections are received by default, and we do not have to >> special case this fetch. >> >> >> WebView application risks >> >> Does this intent deprecate or change behavior of existing APIs, such that >> it has potentially high risk for Android WebView-based applications? >> >> None >> >> >> Debuggability >> >> We surface errors when there is a network problem with the ID assertion >> fetch. This will help developers understand when this feature introduces a >> problem in their FedCM calls. >> >> >> Will this feature be supported on all six Blink platforms (Windows, Mac, >> Linux, ChromeOS, Android, and Android WebView)? >> >> No. FedCM is not supported on Android WebView. >> >> Is this feature fully tested by web-platform-tests >> <https://chromium.googlesource.com/chromium/src/+/main/docs/testing/web_platform_tests.md> >> ? >> >> https://wpt.fyi/results/credential-management/fedcm-identity >> -assertion-nocors.https.html?label=experimental&label=master&aligned >> (will pass on Chrome once we ship) >> >> Flag name on chrome://flags >> >> None >> >> Finch feature name >> >> FedCmIdAssertionCORS >> >> Requires code in //chrome? >> >> True (because FedCM API does) >> >> Tracking bug >> >> https://issues.chromium.org/issues/40284123 >> >> Estimated milestones >> >> DevTrial on desktop >> >> 120 >> >> >> DevTrial on Android >> >> 120 >> >> We want to ship on M124 >> >> Anticipated spec changes >> >> Open questions about a feature may be a source of future web compat or >> interop issues. Please list open issues (e.g. links to known github issues >> in the project for the feature specification) whose resolution may >> introduce web compat/interop risk (e.g., changing to naming or structure of >> the API in a non-backward-compatible way). >> >> https://github.com/whatwg/fetch/issues/1637 >> >> Link to entry on the Chrome Platform Status >> >> https://chromestatus.com/feature/5094763339710464 >> >> This intent message was generated by Chrome Platform Status >> <https://chromestatus.com/>. >> >> -- >> You received this message because you are subscribed to the Google Groups >> "blink-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to blink-dev+unsubscr...@chromium.org. >> To view this discussion on the web visit https://groups.google.com/a/ch >> romium.org/d/msgid/blink-dev/1814484e-4a0c-4210-b936-29ead46 >> f32c5n%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/1814484e-4a0c-4210-b936-29ead46f32c5n%40chromium.org?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "blink-dev" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to blink-dev+unsubscr...@chromium.org. >> To view this discussion on the web visit https://groups.google.com/a/ch >> romium.org/d/msgid/blink-dev/91c26d40-ccc9-4abe-bf97-38cd9e4 >> 8f684%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/91c26d40-ccc9-4abe-bf97-38cd9e48f684%40chromium.org?utm_medium=email&utm_source=footer> >> . >> >> -- >> You received this message because you are subscribed to the Google Groups >> "blink-dev" group. >> >> To unsubscribe from this group and stop receiving emails from it, send an >> email to blink-dev+...@chromium.org. >> >> To view this discussion on the web visit https://groups.google.com/a/ch >> romium.org/d/msgid/blink-dev/a349c863-9904-491f-9e9d-3122768 >> 3d4ffn%40chromium.org >> <https://groups.google.com/a/chromium.org/d/msgid/blink-dev/a349c863-9904-491f-9e9d-31227683d4ffn%40chromium.org?utm_medium=email&utm_source=footer> >> . >> >> -- You received this message because you are subscribed to the Google Groups "blink-dev" group. 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