From 215937729650e7b6fe97cbbf732c2466279bbc44 Mon Sep 17 00:00:00 2001
From: Jamie Mansfield <jmansfield@cadixdev.org>
Date: Wed, 29 May 2024 19:27:27 +0100
Subject: [PATCH] LibWeb: Upgrade mixed requests to potentially trustworthy
 URLs

(if appropriate)
---
 .../LibWeb/Fetch/Fetching/Fetching.cpp        |  4 ++-
 .../MixedContent/AbstractOperations.cpp       | 30 +++++++++++++++++++
 .../LibWeb/MixedContent/AbstractOperations.h  |  2 ++
 3 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibWeb/Fetch/Fetching/Fetching.cpp b/Userland/Libraries/LibWeb/Fetch/Fetching/Fetching.cpp
index 02e6e67bf11..222db7178c2 100644
--- a/Userland/Libraries/LibWeb/Fetch/Fetching/Fetching.cpp
+++ b/Userland/Libraries/LibWeb/Fetch/Fetching/Fetching.cpp
@@ -237,7 +237,9 @@ WebIDL::ExceptionOr<JS::GCPtr<PendingResponse>> main_fetch(JS::Realm& realm, Inf
 
     // FIXME: 4. Run report Content Security Policy violations for request.
     // FIXME: 5. Upgrade request to a potentially trustworthy URL, if appropriate.
-    // FIXME: 6. Upgrade a mixed content request to a potentially trustworthy URL, if appropriate.
+
+    // 6. Upgrade a mixed content request to a potentially trustworthy URL, if appropriate.
+    MixedContent::upgrade_a_mixed_content_request_to_a_potentially_trustworthy_url_if_appropriate(request);
 
     // 7. If should request be blocked due to a bad port, should fetching request be blocked as mixed content, or
     //    should request be blocked by Content Security Policy returns blocked, then set response to a network error.
diff --git a/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.cpp b/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.cpp
index 552d99ffb15..73acf022d72 100644
--- a/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.cpp
+++ b/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.cpp
@@ -10,6 +10,36 @@
 
 namespace Web::MixedContent {
 
+// https://w3c.github.io/webappsec-mixed-content/#upgrade-algorithm
+void upgrade_a_mixed_content_request_to_a_potentially_trustworthy_url_if_appropriate(Fetch::Infrastructure::Request& request)
+{
+    // 1. If one or more of the following conditions is met, return without modifying request:
+    if (
+        // 1. request’s URL is a potentially trustworthy URL.
+        SecureContexts::is_url_potentially_trustworthy(request.url()) == SecureContexts::Trustworthiness::PotentiallyTrustworthy
+
+        // 2. request’s URL’s host is an IP address.
+        || request.url().host().has<URL::IPv4Address>() || request.url().host().has<URL::IPv6Address>()
+
+        // 3. § 4.3 Does settings prohibit mixed security contexts? returns "Does Not Restrict Mixed Security Contents" when applied to request’s client.
+        || does_settings_prohibit_mixed_security_contexts(request.client()) == ProhibitsMixedSecurityContexts::DoesNotRestrictMixedSecurityContexts
+
+        // 4. request’s destination is not "image", "audio", or "video".
+        || (request.destination() != Fetch::Infrastructure::Request::Destination::Image
+            && request.destination() != Fetch::Infrastructure::Request::Destination::Audio
+            && request.destination() != Fetch::Infrastructure::Request::Destination::Video)
+
+        // 5. request’s destination is "image" and request’s initiator is "imageset".
+        || (request.destination() == Fetch::Infrastructure::Request::Destination::Image
+            && request.initiator() == Fetch::Infrastructure::Request::Initiator::ImageSet)) {
+        return;
+    }
+
+    // 2. If request’s URL’s scheme is http, set request’s URL’s scheme to https, and return.
+    if (request.url().scheme() == "http")
+        request.url().set_scheme("https"_string);
+}
+
 // https://w3c.github.io/webappsec-mixed-content/#categorize-settings-object
 ProhibitsMixedSecurityContexts does_settings_prohibit_mixed_security_contexts(JS::GCPtr<HTML::EnvironmentSettingsObject> settings)
 {
diff --git a/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.h b/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.h
index 8234bd44992..c46121a16ec 100644
--- a/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.h
+++ b/Userland/Libraries/LibWeb/MixedContent/AbstractOperations.h
@@ -12,6 +12,8 @@
 
 namespace Web::MixedContent {
 
+void upgrade_a_mixed_content_request_to_a_potentially_trustworthy_url_if_appropriate(Fetch::Infrastructure::Request&);
+
 enum class ProhibitsMixedSecurityContexts {
     ProhibitsMixedSecurityContexts,
     DoesNotRestrictMixedSecurityContexts,