Bypass data reduction proxy when using VPN

If the tun interface is present, disable the data reduction proxy.

BUG=357129

Review URL: https://codereview.chromium.org/373153003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@283478 0039d316-1c4b-4281-b951-d872f2087c98

components/data_reduction_proxy/browser/data_reduction_proxy_settings.cc

@@ -24,6 +24,7 @@
 #include "net/base/host_port_pair.h"
 #include "net/base/load_flags.h"
 #include "net/base/net_errors.h"
+#include "net/base/net_util.h"
 #include "net/http/http_network_session.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/url_fetcher.h"
@@ -36,6 +37,14 @@
 using base::StringPrintf;
 
 namespace {
+// Values of the UMA DataReductionProxy.NetworkChangeEvents histograms.
+// This enum must remain synchronized with the enum of the same
+// name in metrics/histograms/histograms.xml.
+enum DataReductionProxyNetworkChangeEvent {
+  IP_CHANGED = 0, // The client IP address changed.
+  DISABLED_ON_VPN = 1, // The proxy is disabled because a VPN is running.
+  CHANGE_EVENT_COUNT = 2 // This must always be last.
+};
 
 // Key of the UMA DataReductionProxy.StartupState histogram.
 const char kUMAProxyStartupStateHistogram[] =
@@ -44,6 +53,13 @@ const char kUMAProxyStartupStateHistogram[] =
 // Key of the UMA DataReductionProxy.ProbeURL histogram.
 const char kUMAProxyProbeURL[] = "DataReductionProxy.ProbeURL";
 
+// Record a network change event.
+void RecordNetworkChangeEvent(DataReductionProxyNetworkChangeEvent event) {
+  UMA_HISTOGRAM_ENUMERATION("DataReductionProxy.NetworkChangeEvents",
+                            event,
+                            CHANGE_EVENT_COUNT);
+}
+
 int64 GetInt64PrefValue(const base::ListValue& list_value, size_t index) {
   int64 val = 0;
   std::string pref_value;
@@ -70,10 +86,10 @@ DataReductionProxySettings::DataReductionProxySettings(
     DataReductionProxyParams* params)
     : restricted_by_carrier_(false),
       enabled_by_user_(false),
+      disabled_on_vpn_(false),
       prefs_(NULL),
       local_state_prefs_(NULL),
-      url_request_context_getter_(NULL),
-      usage_stats_(NULL) {
+      url_request_context_getter_(NULL) {
   DCHECK(params);
   params_.reset(params);
 }
@@ -312,6 +328,9 @@ void DataReductionProxySettings::OnIPAddressChanged() {
   DCHECK(thread_checker_.CalledOnValidThread());
   if (enabled_by_user_) {
     DCHECK(params_->allowed());
+    RecordNetworkChangeEvent(IP_CHANGED);
+    if (DisableIfVPN())
+      return;
     ProbeWhetherDataReductionProxyIsAvailable();
     WarmProxyConnection();
   }
@@ -360,13 +379,13 @@ void DataReductionProxySettings::MaybeActivateDataReductionProxy(
 
   // Configure use of the data reduction proxy if it is enabled.
   enabled_by_user_= IsDataReductionProxyEnabled();
-  SetProxyConfigs(enabled_by_user_,
+  SetProxyConfigs(enabled_by_user_ && !disabled_on_vpn_,
                   IsDataReductionProxyAlternativeEnabled(),
                   restricted_by_carrier_,
                   at_startup);
 
   // Check if the proxy has been restricted explicitly by the carrier.
-  if (enabled_by_user_) {
+  if (enabled_by_user_ && !disabled_on_vpn_) {
     ProbeWhetherDataReductionProxyIsAvailable();
     WarmProxyConnection();
   }
@@ -426,6 +445,12 @@ void DataReductionProxySettings::RecordStartupState(ProxyStartupState state) {
                             PROXY_STARTUP_STATE_COUNT);
 }
 
+void DataReductionProxySettings::GetNetworkList(
+    net::NetworkInterfaceList* interfaces,
+    int policy) {
+  net::GetNetworkList(interfaces, policy);
+}
+
 void DataReductionProxySettings::ResetParamsForTest(
     DataReductionProxyParams* params) {
   params_.reset(params);
@@ -486,18 +511,6 @@ void DataReductionProxySettings::GetContentLengths(
       local_state->GetInt64(prefs::kDailyHttpContentLengthLastUpdateDate);
 }
 
-// static
-base::string16 DataReductionProxySettings::AuthHashForSalt(
-    int64 salt,
-    const std::string& key) {
-  std::string salted_key =
-      base::StringPrintf("%lld%s%lld",
-                         static_cast<long long>(salt),
-                         key.c_str(),
-                         static_cast<long long>(salt));
-  return base::UTF8ToUTF16(base::MD5String(salted_key));
-}
-
 net::URLFetcher* DataReductionProxySettings::GetBaseURLFetcher(
     const GURL& gurl,
     int load_flags) {
@@ -543,4 +556,36 @@ void DataReductionProxySettings::WarmProxyConnection() {
   warmup_fetcher_->Start();
 }
 
+bool DataReductionProxySettings::DisableIfVPN() {
+  net::NetworkInterfaceList network_interfaces;
+  GetNetworkList(&network_interfaces, 0);
+  // VPNs use a "tun" interface, so the presence of a "tun" interface indicates
+  // a VPN is in use.
+  // TODO(kundaji): Verify this works on Windows.
+  const std::string vpn_interface_name_prefix = "tun";
+  for (size_t i = 0; i < network_interfaces.size(); ++i) {
+    std::string interface_name = network_interfaces[i].name;
+    if (LowerCaseEqualsASCII(
+        interface_name.begin(),
+        interface_name.begin() + vpn_interface_name_prefix.size(),
+        vpn_interface_name_prefix.c_str())) {
+      SetProxyConfigs(false,
+                      IsDataReductionProxyAlternativeEnabled(),
+                      false,
+                      false);
+      disabled_on_vpn_ = true;
+      RecordNetworkChangeEvent(DISABLED_ON_VPN);
+      return true;
+    }
+  }
+  if (disabled_on_vpn_) {
+    SetProxyConfigs(enabled_by_user_,
+                    IsDataReductionProxyAlternativeEnabled(),
+                    restricted_by_carrier_,
+                    false);
+  }
+  disabled_on_vpn_ = false;
+  return false;
+}
+
 }  // namespace data_reduction_proxy

components/data_reduction_proxy/browser/data_reduction_proxy_settings.h

@@ -16,6 +16,7 @@
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_configurator.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_params.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_usage_stats.h"
+#include "net/base/net_util.h"
 #include "net/base/network_change_notifier.h"
 #include "net/url_request/url_fetcher_delegate.h"
 
@@ -208,12 +209,20 @@ class DataReductionProxySettings
   // customer feedback. Virtual so tests can mock it for verification.
   virtual void LogProxyState(bool enabled, bool restricted, bool at_startup);
 
-  // Virtualized for mocking
+  // Virtualized for mocking. Records UMA containing the result of requesting
+  // the probe URL.
   virtual void RecordProbeURLFetchResult(
       data_reduction_proxy::ProbeURLFetchResult result);
+
+  // Virtualized for mocking. Records UMA specifying whether the proxy was
+  // enabled or disabled at startup.
   virtual void RecordStartupState(
       data_reduction_proxy::ProxyStartupState state);
 
+  // Virtualized for mocking. Returns the list of network interfaces in use.
+  virtual void GetNetworkList(net::NetworkInterfaceList* interfaces,
+                              int policy);
+
   DataReductionProxyConfigurator* configurator() {
     return configurator_.get();
   }
@@ -273,18 +282,17 @@ class DataReductionProxySettings
   // Warms the connection to the data reduction proxy.
   void WarmProxyConnection();
 
+  // Disables use of the data reduction proxy on VPNs. Returns true if the
+  // data reduction proxy has been disabled.
+  bool DisableIfVPN();
+
   // Generic method to get a URL fetcher.
   net::URLFetcher* GetBaseURLFetcher(const GURL& gurl, int load_flags);
 
-  // Returns a UTF16 string that's the hash of the configured authentication
-  // |key| and |salt|. Returns an empty UTF16 string if no key is configured or
-  // the data reduction proxy feature isn't available.
-  static base::string16 AuthHashForSalt(int64 salt,
-                                        const std::string& key);
-
   std::string key_;
   bool restricted_by_carrier_;
   bool enabled_by_user_;
+  bool disabled_on_vpn_;
 
   scoped_ptr<net::URLFetcher> fetcher_;
   scoped_ptr<net::URLFetcher> warmup_fetcher_;

components/data_reduction_proxy/browser/data_reduction_proxy_settings_test_utils.h

@@ -6,10 +6,12 @@
 #define COMPONENTS_DATA_REDUCTION_PROXY_BROWSER_DATA_REDUCTION_PROXY_SETTINGS_TEST_UTILS_H_
 
 
+#include "base/memory/scoped_ptr.h"
 #include "base/prefs/testing_pref_service.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_configurator.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_params_test_utils.h"
 #include "components/data_reduction_proxy/browser/data_reduction_proxy_settings.h"
+#include "net/base/net_util.h"
 #include "net/url_request/test_url_fetcher_factory.h"
 #include "net/url_request/url_request_test_util.h"
 #include "testing/gmock/include/gmock/gmock.h"
@@ -85,6 +87,15 @@ class MockDataReductionProxySettings : public C {
     EXPECT_CALL(*this, LogProxyState(enabled, restricted, at_startup)).Times(1);
     C::SetProxyConfigs(enabled, alternative_enabled, restricted, at_startup);
   }
+  virtual void GetNetworkList(net::NetworkInterfaceList* interfaces,
+                              int policy) OVERRIDE {
+    if (!network_interfaces_.get())
+      return;
+    for (size_t i = 0; i < network_interfaces_->size(); ++i)
+      interfaces->push_back(network_interfaces_->at(i));
+  }
+
+  scoped_ptr<net::NetworkInterfaceList> network_interfaces_;
 };
 
 class DataReductionProxySettingsTestBase : public testing::Test {

components/data_reduction_proxy/browser/data_reduction_proxy_settings_unittest.cc

@@ -296,8 +296,39 @@ TEST_F(DataReductionProxySettingsTest, TestOnIPAddressChanged) {
                        true,
                        true,
                        false);
-  // IP address change triggers a probe that succeed. Proxy is unrestricted.
-  CheckProbeOnIPChange(kProbeURLWithBadResponse,
+  // IP address change triggers a probe that succeeds. Proxy is unrestricted.
+  CheckProbeOnIPChange(kProbeURLWithOKResponse,
+                       kWarmupURLWithNoContentResponse,
+                       "OK",
+                       true,
+                       false,
+                       false);
+  // Simulate a VPN connection. The proxy should be disabled.
+  MockSettings* settings = static_cast<MockSettings*>(settings_.get());
+  settings->network_interfaces_.reset(new net::NetworkInterfaceList());
+  settings->network_interfaces_->push_back(
+      net::NetworkInterface("tun0",  /* network interface name */
+                            "tun0",  /* network interface friendly name */
+                            0,  /* interface index */
+                            net::NetworkChangeNotifier::CONNECTION_WIFI,
+                            net::IPAddressNumber(), /* IP address */
+                            0  /* network prefix */
+                            ));
+  settings_->OnIPAddressChanged();
+  base::MessageLoop::current()->RunUntilIdle();
+  CheckProxyConfigs(false, false, false);
+
+  // Check that the proxy is re-enabled if a non-VPN connection is later used.
+  settings->network_interfaces_.reset(new net::NetworkInterfaceList());
+  settings->network_interfaces_->push_back(
+      net::NetworkInterface("eth0",  /* network interface name */
+                            "eth0",  /* network interface friendly name */
+                            0,  /* interface index */
+                            net::NetworkChangeNotifier::CONNECTION_WIFI,
+                            net::IPAddressNumber(),
+                            0  /* network prefix */
+                            ));
+  CheckProbeOnIPChange(kProbeURLWithOKResponse,
                        kWarmupURLWithNoContentResponse,
                        "OK",
                        true,

tools/metrics/histograms/histograms.xml

@@ -3129,6 +3129,16 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   </summary>
 </histogram>
 
+<histogram name="DataReductionProxy.NetworkChangeEvents"
+    enum="DataReductionProxyNetworkChangeEvent">
+  <owner>bengr@chromium.org</owner>
+  <owner>megjablon@chromium.org</owner>
+  <summary>
+    Counts the number of times various events occur when the data reduction
+    proxy is enabled and the IP address of the client changes.
+  </summary>
+</histogram>
+
 <histogram name="DataReductionProxy.ProbeURL"
     enum="DataReductionProxyProbeURLFetchResult">
   <owner>bengr@chromium.org</owner>
@@ -36371,6 +36381,11 @@ Therefore, the affected-histogram name has to have at least one dot in it.
   <int value="10" label="Bypass due to any network error"/>
 </enum>
 
+<enum name="DataReductionProxyNetworkChangeEvent" type="int">
+  <int value="0" label="IP Address Change"/>
+  <int value="1" label="Proxy disabled on VPN"/>
+</enum>
+
 <enum name="DataReductionProxyProbeURLFetchResult" type="int">
   <int value="0" label="Internet disconnected"/>
   <int value="1" label="Probe failed, proxy disabled"/>