Proxy private UMA pepper interface for out-of-process and NaCl plugins.

chrome/renderer/pepper/pepper_uma_renderer_host.cc

+// Copyright (c) 2013 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/renderer/pepper/pepper_uma_renderer_host.h"
+
+#include "base/metrics/histogram.h"
+#include "base/sha1.h"
+#include "base/strings/string_number_conversions.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/renderer/chrome_content_renderer_client.h"
+#include "content/public/renderer/renderer_ppapi_host.h"
+#include "extensions/common/constants.h"
+#include "extensions/common/extension.h"
+#include "ppapi/c/pp_errors.h"
+#include "ppapi/host/dispatch_host_message.h"
+#include "ppapi/host/host_message_context.h"
+#include "ppapi/host/ppapi_host.h"
+#include "ppapi/proxy/ppapi_messages.h"
+
+namespace {
+
+const char* kPredefinedAllowedUMAOrigins[] = {
+  "6EAED1924DB611B6EEF2A664BD077BE7EAD33B8F",  // see crbug.com/317833
+  "4EB74897CB187C7633357C2FE832E0AD6A44883A"   // see crbug.com/317833
+};
+
+const char* kWhitelistedHistogramHashes[] = {
+  "F131550DAB7A7C6E6633EF81FB5998CC0482AC63",  // see crbug.com/317833
+  "BFA80E7D71DE24D08B7363B108CD6DABFF24B9A0",  // see crbug.com/317833
+  "13955AB4DAD798384DFB4304734FCF2A95F353CC",  // see crbug.com/317833
+  "404E800582901F1B937B8E287235FC603A5DEDFB",  // see crbug.com/317833
+  "D95DDB0F180CF797AD30E221D659A9E2B6404BC8"   // see crbug.com/317833
+};
+
+std::string HashHistogram(const std::string& histogram) {
+  const std::string id_hash = base::SHA1HashString(histogram);
+  DCHECK_EQ(id_hash.length(), base::kSHA1Length);
+  return base::HexEncode(id_hash.c_str(), id_hash.length());
+}
+
+}  // namespace
+
+PepperUMARendererHost::PepperUMARendererHost(
+    content::RendererPpapiHost* host,
+    PP_Instance instance,
+    PP_Resource resource)
+    : ResourceHost(host->GetPpapiHost(), instance, resource),
+      document_url_(host->GetDocumentURL(instance)),
+      is_plugin_in_process_(host->IsRunningInProcess()) {
+  for (size_t i = 0; i < arraysize(kPredefinedAllowedUMAOrigins); ++i)
+    allowed_origins_.insert(kPredefinedAllowedUMAOrigins[i]);
+  for (size_t i = 0; i < arraysize(kWhitelistedHistogramHashes); ++i)
+    allowed_histograms_.insert(kWhitelistedHistogramHashes[i]);
+}
+
+PepperUMARendererHost::~PepperUMARendererHost() {
+}
+
+int32_t PepperUMARendererHost::OnResourceMessageReceived(
+    const IPC::Message& msg,
+    ppapi::host::HostMessageContext* context) {
+  IPC_BEGIN_MESSAGE_MAP(PepperUMARendererHost, msg)
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(PpapiHostMsg_UMA_HistogramCustomTimes,
+        OnHistogramCustomTimes);
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(PpapiHostMsg_UMA_HistogramCustomCounts,
+        OnHistogramCustomCounts);
+    PPAPI_DISPATCH_HOST_RESOURCE_CALL(PpapiHostMsg_UMA_HistogramEnumeration,
+        OnHistogramEnumeration);
+  IPC_END_MESSAGE_MAP()
+  return PP_ERROR_FAILED;
+}
+
+bool PepperUMARendererHost::IsHistogramAllowed(const std::string& histogram) {
+  bool is_whitelisted =

[yzshen1, 2013/12/04 19:32:51]

please move this to be right above where it is used.

[elijahtaylor1, 2013/12/21 02:26:21]

Done.

+      ChromeContentRendererClient::IsExtensionOrSharedModuleWhitelisted(
+          document_url_, allowed_origins_);
+
+  const std::string nacl_prefix = "NaCl.";
+  if (is_plugin_in_process_ &&
+      histogram.substr(0, nacl_prefix.size()) == nacl_prefix) {

[bbudge, 2013/12/04 21:08:30]

You could avoid some string creation by using find:
histogram.find("NaCl.") == 0

[elijahtaylor1, 2013/12/21 02:26:21]

Done.

+    return true;
+  }
+
+  if (is_whitelisted && allowed_histograms_.count(HashHistogram(histogram)) > 0)

[bbudge, 2013/12/04 21:08:30]

allowed_histograms_.find is clearer and potentially faster.

[elijahtaylor1, 2013/12/21 02:26:21]

Done.

+    return true;
+
+  LOG(ERROR) << "Host or histogram name is not allowed to use the UMA API.";
+  return false;
+}
+
+int32_t PepperUMARendererHost::OnHistogramCustomTimes(
+    ppapi::host::HostMessageContext* context,
+    const std::string& name,
+    int64_t sample,

[yzshen1, 2013/12/04 19:32:51]

Do you need to validate the inputs? (>0; min <= max; etc.)

[elijahtaylor1, 2013/12/21 02:26:21]

Brought over a similar macro that was in the in-process impl before.  (Didn't
want to duplicate the checks in each function, and didn't want to make a
template function because the arg types are all over the place)

+    int64_t min,
+    int64_t max,
+    uint32_t bucket_count) {
+  if (!IsHistogramAllowed(name)) {
+    return PP_ERROR_NOACCESS;
+  }
+  base::HistogramBase* counter =
+      base::Histogram::FactoryTimeGet(
+          name,
+          base::TimeDelta::FromMilliseconds(min),
+          base::TimeDelta::FromMilliseconds(max),
+          bucket_count,
+          base::HistogramBase::kUmaTargetedHistogramFlag);
+  counter->AddTime(base::TimeDelta::FromMilliseconds(sample));
+  return PP_OK;
+}
+
+int32_t PepperUMARendererHost::OnHistogramCustomCounts(
+    ppapi::host::HostMessageContext* context,
+    const std::string& name,
+    int32_t sample,
+    int32_t min,
+    int32_t max,
+    uint32_t bucket_count) {
+  if (!IsHistogramAllowed(name)) {
+    return PP_ERROR_NOACCESS;
+  }
+  base::HistogramBase* counter =
+      base::Histogram::FactoryGet(
+          name,
+          min,
+          max,
+          bucket_count,
+          base::HistogramBase::kUmaTargetedHistogramFlag);
+  counter->Add(sample);
+  return PP_OK;
+}
+
+int32_t PepperUMARendererHost::OnHistogramEnumeration(
+    ppapi::host::HostMessageContext* context,
+    const std::string& name,
+    int32_t sample,
+    int32_t boundary_value) {
+  if (!IsHistogramAllowed(name)) {
+    return PP_ERROR_NOACCESS;
+  }
+  base::HistogramBase* counter =
+      base::Histogram::FactoryGet(
+          name,
+          1,
+          boundary_value,
+          boundary_value + 1,
+          base::HistogramBase::kUmaTargetedHistogramFlag);
+  counter->Add(sample);
+  return PP_OK;
+}
+