LibWeb: Update Fetch's compute the redirect-taint concept

Author: https://github.com/kennethmyhra
Commit: 0dc2fb3781
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/5826
Reviewed-by: https://github.com/trflynn89 ✅

Libraries/LibWeb/Fetch/Fetching/Fetching.cpp

@@ -545,9 +545,8 @@ WebIDL::ExceptionOr<GC::Ptr<PendingResponse>> main_fetch(JS::Realm& realm, Infra
             if (internal_response->url_list().is_empty())
                 internal_response->set_url_list(request->url_list());
 
-            // 17. If request has a redirect-tainted origin, then set internalResponse’s has-cross-origin-redirects to true.
-            if (request->has_redirect_tainted_origin())
-                internal_response->set_has_cross_origin_redirects(true);
+            // 17. Set internalResponse’s redirect taint to request’s redirect-taint.
+            internal_response->set_redirect_taint(request->redirect_taint());
 
             // 18. If request’s timing allow failed flag is unset, then set internalResponse’s timing allow passed flag.
             if (!request->timing_allow_failed())
@@ -706,8 +705,8 @@ void fetch_response_handover(JS::Realm& realm, Infrastructure::FetchParams const
             // 6. Let responseStatus be 0.
             auto response_status = 0;
 
-            // 7. If fetchParams’s request’s mode is not "navigate" or response’s has-cross-origin-redirects is false:
-            if (fetch_params.request()->mode() != Infrastructure::Request::Mode::Navigate || !response.has_cross_origin_redirects()) {
+            // 7. If fetchParams’s request’s mode is not "navigate" or response’s redirect taint is "same-origin":
+            if (fetch_params.request()->mode() != Infrastructure::Request::Mode::Navigate || response.redirect_taint() == Infrastructure::RedirectTaint::SameOrigin) {
                 // 1. Set responseStatus to response’s status.
                 response_status = response.status();
 

Libraries/LibWeb/Fetch/Infrastructure/HTTP.h

@@ -47,6 +47,12 @@ enum class HttpQuotedStringExtractValue {
     Yes,
 };
 
+enum class RedirectTaint {
+    SameOrigin,
+    SameSite,
+    CrossSite,
+};
+
 [[nodiscard]] String collect_an_http_quoted_string(GenericLexer& lexer, HttpQuotedStringExtractValue extract_value = HttpQuotedStringExtractValue::No);
 
 }

Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.cpp

@@ -164,14 +164,19 @@ bool Request::is_navigation_request() const
 }
 
 // https://fetch.spec.whatwg.org/#concept-request-tainted-origin
-bool Request::has_redirect_tainted_origin() const
+RedirectTaint Request::redirect_taint() const
 {
-    // A request request has a redirect-tainted origin if these steps return true:
+    // 1. Assert: request’s origin is not "client".
+    if (auto const* origin = m_origin.get_pointer<Origin>())
+        VERIFY(*origin != Origin::Client);
 
-    // 1. Let lastURL be null.
+    // 2. Let lastURL be null.
     Optional<URL::URL const&> last_url;
 
-    // 2. For each url of request’s URL list:
+    // 3. Let taint be "same-origin".
+    auto taint = RedirectTaint::SameOrigin;
+
+    // 4. For each url of request’s URL list:
     for (auto const& url : m_url_list) {
         // 1. If lastURL is null, then set lastURL to url and continue.
         if (!last_url.has_value()) {
@@ -179,29 +184,41 @@ bool Request::has_redirect_tainted_origin() const
             continue;
         }
 
-        // 2. If url’s origin is not same origin with lastURL’s origin and request’s origin is not same origin with lastURL’s origin, then return true.
+        // 2. If url’s origin is not same site with lastURL’s origin and request’s origin is not same site with
+        //    lastURL’s origin, then return "cross-site".
         auto const* request_origin = m_origin.get_pointer<URL::Origin>();
-        if (!url.origin().is_same_origin(last_url->origin())
-            && (request_origin == nullptr || !request_origin->is_same_origin(last_url->origin()))) {
-            return true;
+        if (!url.origin().is_same_site(last_url->origin())
+            && (request_origin == nullptr || !request_origin->is_same_site(last_url->origin()))) {
+            return RedirectTaint::CrossSite;
         }
 
-        // 3. Set lastURL to url.
+        // 3. If url’s origin is not same origin with lastURL’s origin and request’s origin is not same origin with
+        //    lastURL’s origin, then set taint to "same-site".
+        if (!url.origin().is_same_origin(last_url->origin())
+            && (request_origin == nullptr || !request_origin->is_same_origin(last_url->origin()))) {
+            taint = RedirectTaint::SameSite;
+        }
+
+        // 4. Set lastURL to url.
         last_url = url;
     }
 
-    // 3. Return false.
-    return false;
+    // 5. Return taint.
+    return taint;
 }
 
 // https://fetch.spec.whatwg.org/#serializing-a-request-origin
 String Request::serialize_origin() const
 {
-    // 1. If request has a redirect-tainted origin, then return "null".
-    if (has_redirect_tainted_origin())
+    // 1. Assert: request’s origin is not "client".
+    if (auto const* origin = m_origin.get_pointer<Origin>())
+        VERIFY(*origin != Origin::Client);
+
+    // 2. If request’s redirect-taint is not "same-origin", then return "null".
+    if (redirect_taint() != RedirectTaint::SameOrigin)
         return "null"_string;
 
-    // 2. Return request’s origin, serialized.
+    // 3. Return request’s origin, serialized.
     return m_origin.get<URL::Origin>().serialize();
 }
 
@@ -358,25 +375,30 @@ void Request::add_origin_header()
 // https://fetch.spec.whatwg.org/#cross-origin-embedder-policy-allows-credentials
 bool Request::cross_origin_embedder_policy_allows_credentials() const
 {
-    // 1. If request’s mode is not "no-cors", then return true.
+    // 1. Assert: request’s origin is not "client".
+    if (auto const* origin = m_origin.get_pointer<Origin>())
+        VERIFY(*origin != Origin::Client);
+
+    // 2. If request’s mode is not "no-cors", then return true.
     if (m_mode != Mode::NoCORS)
         return true;
 
-    // 2. If request’s client is null, then return true.
+    // 3. If request’s client is null, then return true.
     if (m_client == nullptr)
         return true;
 
-    // 3. If request’s client’s policy container’s embedder policy’s value is not "credentialless", then return true.
+    // 4. If request’s client’s policy container’s embedder policy’s value is not "credentialless", then return true.
     if (m_policy_container.has<GC::Ref<HTML::PolicyContainer>>() && m_policy_container.get<GC::Ref<HTML::PolicyContainer>>()->embedder_policy.value != HTML::EmbedderPolicyValue::Credentialless)
         return true;
 
-    // 4. If request’s origin is same origin with request’s current URL’s origin and request does not have a redirect-tainted origin, then return true.
-    // 5. Return false.
+    // 5. If request’s origin is same origin with request’s current URL’s origin and request’s redirect-taint is not
+    //    "same-origin", then return true.
+    // 6. Return false.
     auto const* request_origin = m_origin.get_pointer<URL::Origin>();
     if (request_origin == nullptr)
         return false;
 
-    return request_origin->is_same_origin(current_url().origin()) && !has_redirect_tainted_origin();
+    return request_origin->is_same_origin(current_url().origin()) && redirect_taint() != RedirectTaint::SameOrigin;
 }
 
 StringView request_destination_to_string(Request::Destination destination)

Libraries/LibWeb/Fetch/Infrastructure/HTTP/Requests.h

@@ -19,6 +19,7 @@
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/Origin.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Fetch/Infrastructure/HTTP.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Bodies.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Headers.h>
 #include <LibWeb/HTML/PolicyContainers.h>
@@ -310,7 +311,7 @@ public:
     [[nodiscard]] bool is_non_subresource_request() const;
     [[nodiscard]] bool is_navigation_request() const;
 
-    [[nodiscard]] bool has_redirect_tainted_origin() const;
+    [[nodiscard]] RedirectTaint redirect_taint() const;
 
     [[nodiscard]] String serialize_origin() const;
     [[nodiscard]] ByteBuffer byte_serialize_origin() const;

Libraries/LibWeb/Fetch/Infrastructure/HTTP/Responses.h

@@ -16,6 +16,7 @@
 #include <LibJS/Forward.h>
 #include <LibJS/Heap/Cell.h>
 #include <LibURL/URL.h>
+#include <LibWeb/Fetch/Infrastructure/HTTP.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Bodies.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Headers.h>
 #include <LibWeb/Fetch/Infrastructure/HTTP/Statuses.h>
@@ -103,8 +104,8 @@ public:
     [[nodiscard]] virtual BodyInfo const& body_info() const { return m_body_info; }
     virtual void set_body_info(BodyInfo body_info) { m_body_info = body_info; }
 
-    [[nodiscard]] bool has_cross_origin_redirects() const { return m_has_cross_origin_redirects; }
-    void set_has_cross_origin_redirects(bool has_cross_origin_redirects) { m_has_cross_origin_redirects = has_cross_origin_redirects; }
+    [[nodiscard]] RedirectTaint redirect_taint() const { return m_redirect_taint; }
+    void set_redirect_taint(RedirectTaint redirect_taint) { m_redirect_taint = move(redirect_taint); }
 
     [[nodiscard]] bool is_aborted_network_error() const;
     [[nodiscard]] bool is_network_error() const;
@@ -188,9 +189,9 @@ private:
     // https://fetch.spec.whatwg.org/#response-service-worker-timing-info
     // FIXME: A response has an associated service worker timing info (null or a service worker timing info), which is initially null.
 
-    // https://fetch.spec.whatwg.org/#response-has-cross-origin-redirects
-    // A response has an associated has-cross-origin-redirects (a boolean), which is initially false.
-    bool m_has_cross_origin_redirects { false };
+    // https://fetch.spec.whatwg.org/#response-redirect-taint
+    // A response has an associated redirect taint ("same-origin", "same-site", or "cross-site"), which is initially "same-origin".
+    RedirectTaint m_redirect_taint { RedirectTaint::SameOrigin };
 
     // FIXME is the type correct?
     u64 current_age() const;