Submit a sample of notification images to Safe Browsing

chrome/browser/safe_browsing/notification_image_reporter.cc

+// Copyright 2017 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/safe_browsing/notification_image_reporter.h"
+
+#include <cmath>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/logging.h"
+#include "base/memory/ptr_util.h"
+#include "base/memory/ref_counted_memory.h"
+#include "base/rand_util.h"
+#include "base/threading/sequenced_worker_pool.h"
+#include "chrome/browser/browser_process.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/safe_browsing/safe_browsing_service.h"
+#include "chrome/common/safe_browsing/csd.pb.h"
+#include "components/safe_browsing_db/database_manager.h"
+#include "components/safe_browsing_db/safe_browsing_prefs.h"
+#include "content/public/browser/browser_thread.h"
+#include "net/url_request/report_sender.h"
+#include "skia/ext/image_operations.h"
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "ui/gfx/codec/png_codec.h"
+#include "ui/gfx/geometry/size.h"
+#include "url/gurl.h"
+
+using content::BrowserThread;
+
+namespace safe_browsing {
+
+namespace {
+
+const size_t kMaxReportsPerDay = 5;
+
+const char kReportingUploadUrl[] =
+    "https://safebrowsing.googleusercontent.com/safebrowsing/clientreport/"
+    "chrome-notification-image";  // TODO(johnme): Confirm URL.
+
+}  // namespace
+
+NotificationImageReporter::NotificationImageReporter(
+    net::URLRequestContext* request_context)
+    : report_sender_(base::MakeUnique<net::ReportSender>(
+          request_context,
+          net::ReportSender::CookiesPreference::DO_NOT_SEND_COOKIES)) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+}
+
+NotificationImageReporter::~NotificationImageReporter() {
+  // Thread on which this is destroyed may vary.
+}
+
+void NotificationImageReporter::ReportNotificationImageOnUI(
+    Profile* profile,
+    const GURL& origin,
+    const SkBitmap& image) {
+  DCHECK_CURRENTLY_ON(BrowserThread::UI);
+  DCHECK_EQ(origin, origin.GetOrigin());

[Nathan Parker, 2017/01/11 22:34:38]

How about DCHECK(origin.is_valid()) as well

[johnme, 2017/01/13 02:38:16]

Done.

+
+  // Skip reporting unless SBER2 Scout is enabled.
+  switch (GetExtendedReportingLevel(*profile->GetPrefs())) {
+    case SBER_LEVEL_OFF:
+    case SBER_LEVEL_LEGACY:
+      return;
+    case SBER_LEVEL_SCOUT:
+      break;
+  }
+
+  // Sample a Finch-controlled fraction only.

[Nathan Parker, 2017/01/11 22:34:38]

I'd suggest adding this now, so we have a kill switch. (Anything that initiates
a request to Google can accidentally turn into a DDoS.)

[johnme, 2017/01/13 02:38:16]

Makes sense, especially since the server isn't yet ready. I haven't gotten
around to this yet in the current iteration of the patch.

+  double report_chance = 0.2;  // TODO(johnme): Get this from Finch.
+  if (base::RandDouble() >= report_chance)
+    return;
+
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(&NotificationImageReporter::ReportNotificationImageOnIO, this,
+                 make_scoped_refptr(g_browser_process->safe_browsing_service()),
+                 origin, image));

[Nathan Parker, 2017/01/11 22:34:38]

Does the image get copied here?

[johnme, 2017/01/13 02:38:16]

No, SkBitmaps have an internal thread safe refcounted storage for the image.

+}
+
+void NotificationImageReporter::ReportNotificationImageOnIO(
+    scoped_refptr<SafeBrowsingService> safe_browsing_service,
+    const GURL& origin,
+    const SkBitmap& image) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  // Skip whitelisted origins to cut down on report volume.
+  if (!safe_browsing_service || !safe_browsing_service->database_manager() ||
+      safe_browsing_service->database_manager()->MatchCsdWhitelistUrl(origin)) {
+    return;
+  }
+
+  // Avoid exceeding kMaxReportsPerDay.
+  base::Time a_day_ago = base::Time::Now() - base::TimeDelta::FromDays(1);
+  while (!report_times_.empty() &&
+         report_times_.front() < /* older than */ a_day_ago) {
+    report_times_.pop();
+  }
+  if (report_times_.size() >= kMaxReportsPerDay)
+    return;
+  report_times_.push(base::Time::Now());
+
+  BrowserThread::GetBlockingPool()->PostWorkerTask(
+      FROM_HERE,
+      base::Bind(
+          &NotificationImageReporter::DownscaleNotificationImageOnBlockingPool,
+          this, origin, image));
+}
+
+void NotificationImageReporter::DownscaleNotificationImageOnBlockingPool(
+    const GURL& origin,
+    const SkBitmap& image) {
+  DCHECK(BrowserThread::GetBlockingPool()->RunsTasksOnCurrentThread());
+
+  // Downscale to fit within 512x512. TODO(johnme): Get this from Finch.
+  const double MAX_SIZE = 512;
+  double scale = std::min(MAX_SIZE / image.width(), MAX_SIZE / image.height());
+  SkBitmap downscaled_image =
+      scale >= 1.0 ? image  // already small enough
+                   : skia::ImageOperations::Resize(
+                         image, skia::ImageOperations::RESIZE_GOOD,
+                         std::lround(scale * image.width()),
+                         std::lround(scale * image.height()));
+
+  // Encode as PNG.
+  std::vector<unsigned char> png_bytes;
+  if (!gfx::PNGCodec::EncodeBGRASkBitmap(downscaled_image, false, &png_bytes)) {
+    NOTREACHED();
+    return;
+  }
+
+  BrowserThread::PostTask(
+      BrowserThread::IO, FROM_HERE,
+      base::Bind(
+          &NotificationImageReporter::SendReportOnIO, this, origin,
+          base::RefCountedBytes::TakeVector(&png_bytes),
+          gfx::Size(image.width(), image.height()),
+          gfx::Size(downscaled_image.width(), downscaled_image.height())));
+}
+
+void NotificationImageReporter::SendReportOnIO(
+    const GURL& origin,
+    scoped_refptr<base::RefCountedMemory> png_data,
+    const gfx::Size& dimensions,
+    const gfx::Size& original_dimensions) {
+  DCHECK_CURRENTLY_ON(BrowserThread::IO);
+
+  NotificationImageReportRequest report;
+  report.set_notification_origin(origin.spec());
+  report.mutable_image()->set_png_data(png_data->front(), png_data->size());
+  report.mutable_image()->mutable_dimensions()->set_width(dimensions.width());
+  report.mutable_image()->mutable_dimensions()->set_height(dimensions.height());
+  if (dimensions != original_dimensions) {
+    report.mutable_image()->mutable_original_dimensions()->set_width(
+        original_dimensions.width());
+    report.mutable_image()->mutable_original_dimensions()->set_height(
+        original_dimensions.height());
+  }
+
+  std::string serialized_report;
+  report.SerializeToString(&serialized_report);
+  report_sender_->Send(GURL(kReportingUploadUrl), "application/octet-stream",
+                       serialized_report, base::Closure(),
+                       base::Callback<void(const GURL&, int)>());
+  // TODO(johnme): Consider logging bandwidth and/or duration to UMA.
+}
+
+}  // namespace safe_browsing