Protego: Add version and os_type in the request proto.

See go/protego-versioned-proto for more details about the motivation.

TODOs:
1. Add UMA metrics. Will do that seprately to keep this CL small and
   the reviewer list short.
3. Add the response_provider field in the proto

Bug: 1119928
Change-Id: Ie15d59b7f4e0b4c0fd236d9c665ad82f02ae2cdd
Fixed: 1119928
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2367443Reviewed-by: Varun Khaneja <vakh@chromium.org>
Reviewed-by: Xinghui Lu <xinghuilu@chromium.org>
Commit-Queue: Varun Khaneja <vakh@chromium.org>
Auto-Submit: Varun Khaneja <vakh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#800387}

components/safe_browsing/content/web_ui/safe_browsing_ui.cc

@@ -1286,9 +1286,40 @@ std::string SerializeRTLookupPing(const RTLookupRequestAndToken& ping) {
       lookupType = "DOWNLOAD";
       break;
   }
-
   request_dict.SetKey("lookup_type", base::Value(lookupType));
 
+  request_dict.SetKey("version", base::Value(request.version()));
+
+  std::string os;
+  switch (request.os_type()) {
+    case RTLookupRequest::OS_TYPE_UNSPECIFIED:
+      DCHECK(false) << "RTLookupRequest::os_type is undefined.";
+      os = "UNSPECIFIED";
+      break;
+    case RTLookupRequest::OS_TYPE_LINUX:
+      os = "LINUX";
+      break;
+    case RTLookupRequest::OS_TYPE_WINDOWS:
+      os = "WINDOWS";
+      break;
+    case RTLookupRequest::OS_TYPE_MAC:
+      os = "MAC";
+      break;
+    case RTLookupRequest::OS_TYPE_ANDROID:
+      os = "ANDROID";
+      break;
+    case RTLookupRequest::OS_TYPE_IOS:
+      os = "IOS";
+      break;
+    case RTLookupRequest::OS_TYPE_CHROME_OS:
+      os = "CHROME_OS";
+      break;
+    case RTLookupRequest::OS_TYPE_FUCHSIA:
+      os = "FUCHSIA";
+      break;
+  }
+  request_dict.SetKey("os", base::Value(os));
+
   std::string request_serialized;
   JSONStringValueSerializer serializer(&request_serialized);
   serializer.set_pretty_print(true);

components/safe_browsing/core/proto/realtimeapi.proto

@@ -35,6 +35,28 @@ message RTLookupRequest {
 
   // The DM Token for Enterprise-enrolled devices (go/uss-dmtoken).
   optional string dm_token = 5;
+
+  // |version| helps the Safe Browsing server understand what verison of the
+  // proto Chrome understands, and also what kinds of behaviours it supports.
+  // It should be incremented when adding new fields and/or when making changes
+  // to how existing fields may be interpreted.
+  // Version 1:
+  //   * Client supports caching with |COVERING_MATCH| verdicts.
+  //   * Client supports the |os_type| field.
+  optional int32 version = 6 [default = 0];
+
+  // The operating system of the client.
+  enum OSType {
+    OS_TYPE_UNSPECIFIED = 0;
+    OS_TYPE_ANDROID = 1;
+    OS_TYPE_CHROME_OS = 2;
+    OS_TYPE_FUCHSIA = 3;
+    OS_TYPE_IOS = 4;
+    OS_TYPE_LINUX = 5;
+    OS_TYPE_MAC = 6;
+    OS_TYPE_WINDOWS = 7;
+  }
+  optional OSType os_type = 7;
 }
 
 message RTLookupResponse {

components/safe_browsing/core/realtime/url_lookup_service_base.cc

@@ -11,6 +11,7 @@
 #include "base/strings/string_piece.h"
 #include "base/task/post_task.h"
 #include "base/time/time.h"
+#include "build/build_config.h"
 #include "components/prefs/pref_service.h"
 #include "components/safe_browsing/core/common/safe_browsing_prefs.h"
 #include "components/safe_browsing/core/common/thread_utils.h"
@@ -38,6 +39,9 @@ const size_t kURLLookupTimeoutDurationInSeconds = 10;  // 10 seconds.
 
 constexpr char kAuthHeaderBearer[] = "Bearer ";
 
+// Represents the value stored in the |version| field of |RTLookupRequest|.
+const int kRTLookupRequestVersion = 1;
+
 // UMA helper functions.
 void RecordBooleanWithAndWithoutSuffix(const std::string& metric,
                                        const std::string& suffix,
@@ -87,6 +91,25 @@ void RecordNetworkResultWithAndWithoutSuffix(const std::string& metric,
       (metric + suffix).c_str(), net_error, response_code);
 }
 
+RTLookupRequest::OSType GetRTLookupRequestOSType() {
+#if defined(OS_ANDROID)
+  return RTLookupRequest::OS_TYPE_ANDROID;
+#elif defined(OS_CHROMEOS)
+  return RTLookupRequest::OS_TYPE_CHROME_OS;
+#elif defined(OS_FUCHSIA)
+  return RTLookupRequest::OS_TYPE_FUCHSIA;
+#elif defined(OS_IOS)
+  return RTLookupRequest::OS_TYPE_IOS;
+#elif defined(OS_LINUX)
+  return RTLookupRequest::OS_TYPE_LINUX;
+#elif defined(OS_MAC)
+  return RTLookupRequest::OS_TYPE_MAC;
+#elif defined(OS_WIN)
+  return RTLookupRequest::OS_TYPE_WINDOWS;
+#endif
+  return RTLookupRequest::OS_TYPE_UNSPECIFIED;
+}
+
 }  // namespace
 
 RealTimeUrlLookupServiceBase::RealTimeUrlLookupServiceBase(
@@ -416,6 +439,8 @@ std::unique_ptr<RTLookupRequest> RealTimeUrlLookupServiceBase::FillRequestProto(
   auto request = std::make_unique<RTLookupRequest>();
   request->set_url(SanitizeURL(url).spec());
   request->set_lookup_type(RTLookupRequest::NAVIGATION);
+  request->set_version(kRTLookupRequestVersion);
+  request->set_os_type(GetRTLookupRequestOSType());
   base::Optional<std::string> dm_token_string = GetDMTokenString();
   if (dm_token_string.has_value()) {
     request->set_dm_token(dm_token_string.value());