From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: deepak1556 <hop2deep@gmail.com>
Date: Tue, 17 Aug 2021 22:42:42 -0700
Subject: feat: expose raw response headers from URLLoader

With https://chromium-review.googlesource.com/c/chromium/src/+/2856099
unfiltered response headers are only available via trusted channel
through //services/network/public/mojom/devtools_observer.mojom.
https://github.com/electron/electron/pull/30503/commits/28f4da1582d046e96cb58f3cbb590503e89dfd0d
was an attempt to use this interface but given the original response is
signalled on a different interface via URLLoaderClient::OnReceiveResponse
it is harder to sync these data from two different channels for a synchronous
event emitted on the SimpleURLLoaderWrapper::OnResponseStarted.

This patch does the minimal approach to add back the raw response
headers, moving forward we should find a way in upstream to provide
access to these headers for loader clients created on the browser process.

diff --git a/services/network/public/cpp/resource_request.cc b/services/network/public/cpp/resource_request.cc
index 189230e448183c52b9da41ecc520b366d1bea14f..689d1ecf00b553c039b9d9e19540cd5a3e053118 100644
--- a/services/network/public/cpp/resource_request.cc
+++ b/services/network/public/cpp/resource_request.cc
@@ -203,6 +203,7 @@ ResourceRequest::TrustedParams& ResourceRequest::TrustedParams::operator=(
   allow_cookies_from_browser = other.allow_cookies_from_browser;
   include_request_cookies_with_response =
       other.include_request_cookies_with_response;
+  report_raw_headers = other.report_raw_headers;
   enabled_client_hints = other.enabled_client_hints;
   cookie_observer =
       Clone(&const_cast<mojo::PendingRemote<mojom::CookieAccessObserver>&>(
@@ -241,6 +242,7 @@ bool ResourceRequest::TrustedParams::EqualsForTesting(
     const TrustedParams& other) const {
   return isolation_info.IsEqualForTesting(other.isolation_info) &&
          disable_secure_dns == other.disable_secure_dns &&
+         report_raw_headers == other.report_raw_headers &&
          has_user_activation == other.has_user_activation &&
          allow_cookies_from_browser == other.allow_cookies_from_browser &&
          include_request_cookies_with_response ==
diff --git a/services/network/public/cpp/resource_request.h b/services/network/public/cpp/resource_request.h
index 415e80174751de75bc9ef92a435679e22c32b39e..df25f808b55bccd72d5edba2be3f06a9f74f2e15 100644
--- a/services/network/public/cpp/resource_request.h
+++ b/services/network/public/cpp/resource_request.h
@@ -116,6 +116,7 @@ struct COMPONENT_EXPORT(NETWORK_CPP_BASE) ResourceRequest {
     bool has_user_activation = false;
     bool allow_cookies_from_browser = false;
     bool include_request_cookies_with_response = false;
+    bool report_raw_headers = false;
     std::optional<EnabledClientHints> enabled_client_hints;
     mojo::PendingRemote<mojom::CookieAccessObserver> cookie_observer;
     mojo::PendingRemote<mojom::TrustTokenAccessObserver> trust_token_observer;
diff --git a/services/network/public/cpp/url_request_mojom_traits.cc b/services/network/public/cpp/url_request_mojom_traits.cc
index 599ea96d28ad13e76c50a2153c59e563fb25b6b6..6b85715c4034f6894d550b62f5cef45e691db967 100644
--- a/services/network/public/cpp/url_request_mojom_traits.cc
+++ b/services/network/public/cpp/url_request_mojom_traits.cc
@@ -67,6 +67,7 @@ bool StructTraits<network::mojom::TrustedUrlRequestParamsDataView,
   out->allow_cookies_from_browser = data.allow_cookies_from_browser();
   out->include_request_cookies_with_response =
       data.include_request_cookies_with_response();
+  out->report_raw_headers = data.report_raw_headers();
   if (!data.ReadEnabledClientHints(&out->enabled_client_hints)) {
     return false;
   }
diff --git a/services/network/public/cpp/url_request_mojom_traits.h b/services/network/public/cpp/url_request_mojom_traits.h
index ce69b40f1738bea97f52ed954a2908c5abdcad8b..67e8b7093a6359afef3044b2e7fc63a86a36425d 100644
--- a/services/network/public/cpp/url_request_mojom_traits.h
+++ b/services/network/public/cpp/url_request_mojom_traits.h
@@ -109,6 +109,10 @@ struct COMPONENT_EXPORT(NETWORK_CPP_BASE)
       const network::ResourceRequest::TrustedParams& trusted_params) {
     return trusted_params.include_request_cookies_with_response;
   }
+  static bool report_raw_headers(
+      const network::ResourceRequest::TrustedParams& trusted_params) {
+    return trusted_params.report_raw_headers;
+  }
   static const std::optional<
       network::ResourceRequest::TrustedParams::EnabledClientHints>&
   enabled_client_hints(
diff --git a/services/network/public/mojom/url_request.mojom b/services/network/public/mojom/url_request.mojom
index 0a0c6d22bdb2ce106e8e18adb5141999167e3f93..e49e8f85bdd122ee263d69efe0ee0abc139e83b3 100644
--- a/services/network/public/mojom/url_request.mojom
+++ b/services/network/public/mojom/url_request.mojom
@@ -111,6 +111,9 @@ struct TrustedUrlRequestParams {
   // client which should not be able to see them.
   bool include_request_cookies_with_response = false;
 
+  // [Electron] Whether to provide unfiltered response headers.
+  bool report_raw_headers;
+
   // Enabled Client Hints to be evaluated quickly within the network layer
   // when it receives the AcceptCHFrame.
   EnabledClientHints? enabled_client_hints;
diff --git a/services/network/public/mojom/url_response_head.mojom b/services/network/public/mojom/url_response_head.mojom
index 13a211107294e856616d1626fa1dc9c79eb5646c..549a36886d665c1a8100f09b7a86c8dc13c80e84 100644
--- a/services/network/public/mojom/url_response_head.mojom
+++ b/services/network/public/mojom/url_response_head.mojom
@@ -14,6 +14,7 @@ import "services/network/public/mojom/encoded_body_length.mojom";
 import "services/network/public/mojom/fetch_api.mojom";
 import "services/network/public/mojom/http_request_headers.mojom";
 import "services/network/public/mojom/ip_address_space.mojom";
+import "services/network/public/mojom/http_raw_headers.mojom";
 import "services/network/public/mojom/ip_endpoint.mojom";
 import "services/network/public/mojom/load_timing_info.mojom";
 import "services/network/public/mojom/load_timing_internal_info.mojom";
@@ -53,6 +54,9 @@ struct URLResponseHead {
   // The response headers or NULL if the URL type does not support headers.
   HttpResponseHeaders headers;
 
+  // Actual response headers, as obtained from the network stack.
+  array<HttpRawHeaderPair> raw_response_headers;
+
   // The mime type of the response.  This may be a derived value.
   string mime_type;
 
diff --git a/services/network/url_loader.cc b/services/network/url_loader.cc
index 1cdafc5c4189c0af64c03b8140ff310e0579d10f..939ebc202ef225387f0e9e77885a7a21aafef559 100644
--- a/services/network/url_loader.cc
+++ b/services/network/url_loader.cc
@@ -373,6 +373,9 @@ URLLoader::URLLoader(
                                   mojo::SimpleWatcher::ArmingPolicy::MANUAL,
                                   TaskRunner(request.priority)),
       per_factory_orb_state_(context.GetMutableOrbState()),
+      report_raw_headers_(
+        request.trusted_params &&
+        request.trusted_params->report_raw_headers),
       devtools_request_id_(request.devtools_request_id),
       options_(PopulateOptions(options,
                                factory_params_->is_orb_enabled,
@@ -570,7 +573,7 @@ void URLLoader::SetUpUrlRequestCallbacks(
         &URLLoader::IsSharedDictionaryReadAllowed, base::Unretained(this)));
   }
 
-  if (devtools_request_id()) {
+  if (devtools_request_id() || report_raw_headers_) {
     url_request_->SetResponseHeadersCallback(base::BindRepeating(
         &URLLoader::SetRawResponseHeaders, base::Unretained(this)));
   }
@@ -1168,6 +1171,19 @@ void URLLoader::OnResponseStarted(net::URLRequest* url_request, int net_error) {
   }
 
   response_ = BuildResponseHead();
+  if (raw_response_headers_ && report_raw_headers_) {
+    std::vector<network::mojom::HttpRawHeaderPairPtr> header_array;
+    size_t iterator = 0;
+    std::string name, value;
+    while (raw_response_headers_->EnumerateHeaderLines(&iterator, &name, &value)) {
+      network::mojom::HttpRawHeaderPairPtr pair =
+          network::mojom::HttpRawHeaderPair::New();
+      pair->key = name;
+      pair->value = value;
+      header_array.push_back(std::move(pair));
+    }
+    response_->raw_response_headers = std::move(header_array);
+  }
   DispatchOnRawResponse();
 
   if (expected_response_headers_for_synthetic_response &&
diff --git a/services/network/url_loader.h b/services/network/url_loader.h
index 3411c79d785cc6f9d6404e6384ec8e97f6bad8d7..9890fee8cba2da4bf126d4849a4ca41e3d3d2209 100644
--- a/services/network/url_loader.h
+++ b/services/network/url_loader.h
@@ -629,6 +629,8 @@ class COMPONENT_EXPORT(NETWORK_SERVICE) URLLoader
   std::unique_ptr<ResourceScheduler::ScheduledResourceRequest>
       resource_scheduler_request_handle_;
 
+  // Whether client requested raw headers.
+  bool report_raw_headers_ = false;
   scoped_refptr<const net::HttpResponseHeaders> raw_response_headers_;
 
   std::unique_ptr<UploadProgressTracker> upload_progress_tracker_;
