Add the ability to use DataReductionProxyParams from DataReductionProxyConfigServiceClient.

- Permit DRP RequestOptions to take auth credentials instead of always internally
  generating them.
- Permit DRP Config to perform a reload of the configuration
- Create a new DRP MutableConfigValues class which can have its underlying values
  updated.
- Add a configuration refresh timer to DRP ConfigServiceClient, along with
  backoff logic.

BUG=466753

Review URL: https://codereview.chromium.org/1024553009

Cr-Commit-Position: refs/heads/master@{#322217}

22 files changed, 1033 insertions, 78 deletions

diff --git a/components/data_reduction_proxy.gypi b/components/data_reduction_proxy.gypi
index 098c8a1..f8b37a5 100644
--- a/components/data_reduction_proxy.gypi
+++ b/components/data_reduction_proxy.gypi
@@ -108,6 +108,8 @@
         'data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h',
         'data_reduction_proxy/core/browser/data_reduction_proxy_metrics.cc',
         'data_reduction_proxy/core/browser/data_reduction_proxy_metrics.h',
+        'data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.cc',
+        'data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h',
         'data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate.cc',
         'data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate.h',
         'data_reduction_proxy/core/browser/data_reduction_proxy_prefs.cc',
diff --git a/components/data_reduction_proxy/core/browser/BUILD.gn b/components/data_reduction_proxy/core/browser/BUILD.gn
index 5790d4c..3e660fd 100644
--- a/components/data_reduction_proxy/core/browser/BUILD.gn
+++ b/components/data_reduction_proxy/core/browser/BUILD.gn
@@ -21,6 +21,8 @@ static_library("browser") {
     "data_reduction_proxy_io_data.h",
     "data_reduction_proxy_metrics.cc",
     "data_reduction_proxy_metrics.h",
+    "data_reduction_proxy_mutable_config_values.cc",
+    "data_reduction_proxy_mutable_config_values.h",
     "data_reduction_proxy_network_delegate.cc",
     "data_reduction_proxy_network_delegate.h",
     "data_reduction_proxy_prefs.cc",
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
index bb7ab76..932af6f 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
@@ -90,6 +90,12 @@ void DataReductionProxyConfig::SetProxyPrefs(bool enabled,
                             alternative_enabled, at_startup));
 }
 
+void DataReductionProxyConfig::ReloadConfig() {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+  UpdateConfigurator(enabled_by_user_, alternative_enabled_by_user_,
+                     restricted_by_carrier_, false /* at_startup */);
+}
+
 bool DataReductionProxyConfig::WasDataReductionProxyUsed(
     const net::URLRequest* request,
     DataReductionProxyTypeInfo* proxy_info) const {
@@ -276,18 +282,31 @@ void DataReductionProxyConfig::UpdateConfigurator(bool enabled,
   LogProxyState(enabled, restricted, at_startup);
   // The alternative is only configured if the standard configuration is
   // is enabled.
-  if (enabled & !config_values_->holdback()) {
+  std::string origin;
+  std::string fallback_origin;
+  std::string ssl_origin;
+  bool fallback_allowed = false;
+  if (enabled && !disabled_on_vpn_ && !config_values_->holdback()) {
     if (alternative_enabled) {
-      configurator_->Enable(restricted,
-                            !config_values_->alternative_fallback_allowed(),
-                            config_values_->alt_origin().ToURI(), std::string(),
-                            config_values_->ssl_origin().ToURI());
+      fallback_allowed = config_values_->alternative_fallback_allowed();
+      if (config_values_->alt_origin().is_valid())
+        origin = config_values_->alt_origin().ToURI();
+      if (config_values_->ssl_origin().is_valid())
+        ssl_origin = config_values_->ssl_origin().ToURI();
     } else {
-      configurator_->Enable(restricted, !config_values_->fallback_allowed(),
-                            config_values_->origin().ToURI(),
-                            config_values_->fallback_origin().ToURI(),
-                            std::string());
+      fallback_allowed = config_values_->fallback_allowed();
+      if (config_values_->origin().is_valid())
+        origin = config_values_->origin().ToURI();
+      if (config_values_->fallback_origin().is_valid())
+        fallback_origin = config_values_->fallback_origin().ToURI();
     }
+  }
+
+  // TODO(jeremyim): Enable should take std::vector<net::ProxyServer> as its
+  // parameters.
+  if (!origin.empty() || !fallback_origin.empty() || !ssl_origin.empty()) {
+    configurator_->Enable(restricted, !fallback_allowed, origin,
+                          fallback_origin, ssl_origin);
   } else {
     configurator_->Disable();
   }
@@ -475,17 +494,18 @@ bool DataReductionProxyConfig::DisableIfVPN() {
             interface_name.begin(),
             interface_name.begin() + vpn_interface_name_prefix.size(),
             vpn_interface_name_prefix.c_str())) {
-      UpdateConfigurator(false, alternative_enabled_by_user_, false, false);
       disabled_on_vpn_ = true;
+      UpdateConfigurator(enabled_by_user_, alternative_enabled_by_user_,
+                         restricted_by_carrier_, false);
       RecordNetworkChangeEvent(DISABLED_ON_VPN);
       return true;
     }
   }
   if (disabled_on_vpn_) {
+    disabled_on_vpn_ = false;
     UpdateConfigurator(enabled_by_user_, alternative_enabled_by_user_,
                        restricted_by_carrier_, false);
   }
-  disabled_on_vpn_ = false;
   return false;
 }
 
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h
index 6573338..69098b7 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h
@@ -90,6 +90,11 @@ class DataReductionProxyConfig
                              bool alternative_enabled,
                              bool at_startup);
 
+  // Provides a mechanism for an external object to force |this| to refresh
+  // the Data Reduction Proxy configuration from |config_values_| and apply to
+  // |configurator_|. Used by the Data Reduction Proxy config service client.
+  void ReloadConfig();
+
   // Returns true if a Data Reduction Proxy was used for the given |request|.
   // If true, |proxy_info.proxy_servers.first| will contain the name of the
   // proxy that was used. |proxy_info.proxy_servers.second| will contain the
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.cc
index 39a9481..59081c3 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.cc
@@ -4,27 +4,169 @@
 
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h"
 
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/bind_helpers.h"
 #include "base/json/json_writer.h"
+#include "base/location.h"
 #include "base/logging.h"
+#include "base/single_thread_task_runner.h"
+#include "base/time/time.h"
 #include "base/values.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_client_config_parser.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
+#include "components/data_reduction_proxy/proto/client_config.pb.h"
+#include "net/base/host_port_pair.h"
+#include "net/proxy/proxy_server.h"
 
 namespace data_reduction_proxy {
 
+namespace {
+
+// This is the default backoff policy used to communicate with the Data
+// Reduction Proxy configuration service.
+const net::BackoffEntry::Policy kDefaultBackoffPolicy = {
+    0,               // num_errors_to_ignore
+    1 * 1000,        // initial_delay_ms
+    4,               // multiply_factor
+    0.10,            // jitter_factor,
+    30 * 60 * 1000,  // maximum_backoff_ms
+    -1,              // entry_lifetime_ms
+    true,            // always_use_initial_delay
+};
+
+// Extracts the list of Data Reduction Proxy servers to use for HTTP requests.
+std::vector<net::ProxyServer> GetProxiesForHTTP(
+    const data_reduction_proxy::ProxyConfig& proxy_config) {
+  std::vector<net::ProxyServer> proxies;
+  for (const auto& server : proxy_config.http_proxy_servers()) {
+    if (server.scheme() != ProxyServer_ProxyScheme_UNSPECIFIED) {
+      proxies.push_back(net::ProxyServer(
+          config_parser::SchemeFromProxyScheme(server.scheme()),
+          net::HostPortPair(server.host(), server.port())));
+    }
+  }
+
+  return proxies;
+}
+
+// Calculate the next time at which the Data Reduction Proxy configuration
+// should be retrieved, based on response success, configuration expiration,
+// and the backoff delay. |backoff_delay| must be non-negative. Note that it is
+// possible for |config_expiration| to be prior to |now|, but on a successful
+// config refresh, |backoff_delay| will be returned.
+base::TimeDelta CalculateNextConfigRefreshTime(
+    bool fetch_succeeded,
+    const base::Time& config_expiration,
+    const base::Time& now,
+    const base::TimeDelta& backoff_delay) {
+  DCHECK(backoff_delay >= base::TimeDelta());
+  if (fetch_succeeded) {
+    base::TimeDelta success_delay = config_expiration - now;
+    if (success_delay > backoff_delay)
+      return success_delay;
+  }
+
+  return backoff_delay;
+}
+
+}  // namespace
+
+const net::BackoffEntry::Policy& GetBackoffPolicy() {
+  return kDefaultBackoffPolicy;
+}
+
 DataReductionProxyConfigServiceClient::DataReductionProxyConfigServiceClient(
-    DataReductionProxyParams* params,
-    DataReductionProxyRequestOptions* request_options)
-    : params_(params),
-      request_options_(request_options) {
-  DCHECK(params);
+    scoped_ptr<DataReductionProxyParams> params,
+    const net::BackoffEntry::Policy& backoff_policy,
+    DataReductionProxyRequestOptions* request_options,
+    DataReductionProxyMutableConfigValues* config_values,
+    DataReductionProxyConfig* config,
+    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner)
+    : params_(params.Pass()),
+      request_options_(request_options),
+      config_values_(config_values),
+      config_(config),
+      io_task_runner_(io_task_runner),
+      backoff_entry_(&backoff_policy) {
   DCHECK(request_options);
+  DCHECK(config_values);
+  DCHECK(config);
+  DCHECK(io_task_runner.get());
+  io_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&DataReductionProxyConfigServiceClient::RetrieveConfig,
+                 base::Unretained(this)));
 }
 
 DataReductionProxyConfigServiceClient::
     ~DataReductionProxyConfigServiceClient() {
 }
 
+void DataReductionProxyConfigServiceClient::RetrieveConfig() {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+
+  std::string static_response = ConstructStaticResponse();
+  ClientConfig config;
+  bool succeeded = false;
+  if (config_parser::ParseClientConfig(static_response, &config)) {
+    if (config.has_proxy_config()) {
+      net::ProxyServer origin;
+      net::ProxyServer fallback_origin;
+      std::vector<net::ProxyServer> proxies =
+          GetProxiesForHTTP(config.proxy_config());
+      if (proxies.size() > 0) {
+        origin = proxies[0];
+        if (proxies.size() > 1)
+          fallback_origin = proxies[1];
+
+        std::string session;
+        std::string credentials;
+        if (DataReductionProxyRequestOptions::ParseLocalSessionKey(
+                config.session_key(), &session, &credentials)) {
+          request_options_->SetCredentials(session, credentials);
+          config_values_->UpdateValues(origin, fallback_origin);
+          config_->ReloadConfig();
+          succeeded = true;
+        }
+      }
+    }
+  }
+
+  base::Time expiration_time;
+  if (succeeded) {
+    expiration_time = config_parser::TimestampToTime(config.expire_time());
+  }
+
+  GetBackoffEntry()->InformOfRequest(succeeded);
+  base::TimeDelta next_config_refresh_time =
+      CalculateNextConfigRefreshTime(succeeded, expiration_time, Now(),
+                                     GetBackoffEntry()->GetTimeUntilRelease());
+  SetConfigRefreshTimer(next_config_refresh_time);
+}
+
+net::BackoffEntry* DataReductionProxyConfigServiceClient::GetBackoffEntry() {
+  return &backoff_entry_;
+}
+
+void DataReductionProxyConfigServiceClient::SetConfigRefreshTimer(
+    const base::TimeDelta& delay) {
+  DCHECK(delay >= base::TimeDelta());
+  config_refresh_timer_.Stop();
+  config_refresh_timer_.Start(
+      FROM_HERE, delay, this,
+      &DataReductionProxyConfigServiceClient::RetrieveConfig);
+}
+
+base::Time DataReductionProxyConfigServiceClient::Now() const {
+  return base::Time::Now();
+}
+
 std::string
 DataReductionProxyConfigServiceClient::ConstructStaticResponse() const {
   std::string response;
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h
index 648cee4..3f6ae23 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h
@@ -9,38 +9,95 @@
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/timer/timer.h"
+#include "net/base/backoff_entry.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+class Time;
+class TimeDelta;
+}
 
 namespace data_reduction_proxy {
 
+class DataReductionProxyConfig;
+class DataReductionProxyMutableConfigValues;
 class DataReductionProxyParams;
 class DataReductionProxyRequestOptions;
 
+// Retrieves the default net::BackoffEntry::Policy for the Data Reduction Proxy
+// configuration service client.
+const net::BackoffEntry::Policy& GetBackoffPolicy();
+
 // Retrieves the Data Reduction Proxy configuration from a remote service. This
 // object lives on the IO thread.
 class DataReductionProxyConfigServiceClient {
  public:
   // The caller must ensure that all parameters remain alive for the lifetime of
-  // the |DataReductionProxyConfigClient|.
+  // the |DataReductionProxyConfigClient|, with the exception of |params|
+  // which this instance will own.
   DataReductionProxyConfigServiceClient(
-      DataReductionProxyParams* params,
-      DataReductionProxyRequestOptions* request_options);
+      scoped_ptr<DataReductionProxyParams> params,
+      const net::BackoffEntry::Policy& backoff_policy,
+      DataReductionProxyRequestOptions* request_options,
+      DataReductionProxyMutableConfigValues* config_values,
+      DataReductionProxyConfig* config,
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
 
-  ~DataReductionProxyConfigServiceClient();
+  virtual ~DataReductionProxyConfigServiceClient();
 
- private:
-  FRIEND_TEST_ALL_PREFIXES(DataReductionProxyConfigClientTest,
-                           TestConstructStaticResponse);
+  // Request the retrieval of the Data Reduction Proxy configuration.
+  void RetrieveConfig();
+
+ protected:
+  // Retrieves the backoff entry object being used to throttle request failures.
+  // Virtual for testing.
+  virtual net::BackoffEntry* GetBackoffEntry();
+
+  // Sets a timer to determine when to next refresh the Data Reduction Proxy
+  // configuration.
+  // Virtual for testing.
+  virtual void SetConfigRefreshTimer(const base::TimeDelta& delay);
+
+  // Returns the current time.
+  // Virtual for testing.
+  virtual base::Time Now() const;
 
   // Constructs a synthetic response based on |params_|.
-  std::string ConstructStaticResponse() const;
+  // Virtual for testing.
+  virtual std::string ConstructStaticResponse() const;
 
-  // The caller must ensure that the |params_| outlives this instance.
-  DataReductionProxyParams* params_;
+ private:
+  FRIEND_TEST_ALL_PREFIXES(DataReductionProxyConfigServiceClientTest,
+                           TestConstructStaticResponse);
+  friend class TestDataReductionProxyConfigServiceClient;
+
+  // Contains the static configuration data to use.
+  scoped_ptr<DataReductionProxyParams> params_;
 
   // The caller must ensure that the |request_options_| outlives this instance.
   DataReductionProxyRequestOptions* request_options_;
 
+  // The caller must ensure that the |config_values_| outlives this instance.
+  DataReductionProxyMutableConfigValues* config_values_;
+
+  // The caller must ensure that the |config_| outlives this instance.
+  DataReductionProxyConfig* config_;
+
+  // |io_task_runner_| should be the task runner for running operations on the
+  // IO thread.
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
+
+  // Used to calculate the backoff time on request failures.
+  net::BackoffEntry backoff_entry_;
+
+  // An event that fires when it is time to refresh the Data Reduction Proxy
+  // configuration.
+  base::OneShotTimer<DataReductionProxyConfigServiceClient>
+      config_refresh_timer_;
+
   DISALLOW_COPY_AND_ASSIGN(DataReductionProxyConfigServiceClient);
 };
 
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client_unittest.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client_unittest.cc
index 6b44ceb..f8e7c0f 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client_unittest.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client_unittest.cc
@@ -7,8 +7,10 @@
 #include <string>
 
 #include "base/memory/scoped_ptr.h"
+#include "base/time/tick_clock.h"
 #include "base/values.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_configurator_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_client_config_parser.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
@@ -19,7 +21,34 @@
 
 namespace data_reduction_proxy {
 
-class DataReductionProxyConfigClientTest : public testing::Test {
+namespace {
+
+class RequestOptionsPopulator {
+ public:
+  RequestOptionsPopulator(const base::Time& expiration_time,
+                          const base::TimeDelta& increment)
+      : expiration_time_(expiration_time),
+        increment_(increment) {
+  }
+
+  void PopulateResponse(base::DictionaryValue* response) {
+    response->SetString("sessionKey", "abcdef|1234-5678-12345678");
+    response->SetString("expireTime",
+                        config_parser::TimeToISO8601(expiration_time_));
+    expiration_time_ += increment_;
+  }
+
+ private:
+  base::Time expiration_time_;
+  base::TimeDelta increment_;
+};
+
+void PopulateResponseFailure(base::DictionaryValue* response) {
+}
+
+}  // namespace
+
+class DataReductionProxyConfigServiceClientTest : public testing::Test {
  protected:
   void SetUp() override {
     test_context_ =
@@ -28,20 +57,62 @@ class DataReductionProxyConfigClientTest : public testing::Test {
                              DataReductionProxyParams::kFallbackAllowed |
                              DataReductionProxyParams::kPromoAllowed)
             .WithParamsDefinitions(TestDataReductionProxyParams::HAS_EVERYTHING)
+            .WithTestConfigurator()
+            .WithMockRequestOptions()
+            .WithTestConfigClient()
             .Build();
+    test_context_->test_config_client()->SetCustomReleaseTime(
+        base::TimeTicks::UnixEpoch());
+    test_context_->test_config_client()->SetNow(base::Time::UnixEpoch());
+  }
+
+  void SetDataReductionProxyEnabled(bool enabled) {
+    test_context_->config()->SetStateForTest(enabled, false, false);
   }
 
   scoped_ptr<DataReductionProxyConfigServiceClient> BuildConfigClient() {
-    return make_scoped_ptr(new DataReductionProxyConfigServiceClient(
-        test_context_->config()->test_params(),
-        test_context_->io_data()->request_options()));
+    scoped_ptr<DataReductionProxyParams> params(new DataReductionProxyParams(
+        DataReductionProxyParams::kAllowed |
+        DataReductionProxyParams::kFallbackAllowed |
+        DataReductionProxyParams::kPromoAllowed));
+    request_options_.reset(
+        new DataReductionProxyRequestOptions(Client::UNKNOWN,
+                                             test_context_->io_data()->config(),
+                                             test_context_->task_runner()));
+    return scoped_ptr<DataReductionProxyConfigServiceClient>(
+        new DataReductionProxyConfigServiceClient(
+            params.Pass(), GetBackoffPolicy(),
+            request_options_.get(),
+            test_context_->mutable_config_values(),
+            test_context_->io_data()->config(), test_context_->task_runner()));
+  }
+
+  DataReductionProxyParams* params() {
+    return test_context_->test_params();
+  }
+
+  TestDataReductionProxyConfigServiceClient* config_client() {
+    return test_context_->test_config_client();
+  }
+
+  TestDataReductionProxyConfigurator* configurator() {
+    return test_context_->test_configurator();
+  }
+
+  MockDataReductionProxyRequestOptions* request_options() {
+    return test_context_->mock_request_options();
+  }
+
+  void RunUntilIdle() {
+    test_context_->RunUntilIdle();
   }
 
  private:
   scoped_ptr<DataReductionProxyTestContext> test_context_;
+  scoped_ptr<DataReductionProxyRequestOptions> request_options_;
 };
 
-TEST_F(DataReductionProxyConfigClientTest, TestConstructStaticResponse) {
+TEST_F(DataReductionProxyConfigServiceClientTest, TestConstructStaticResponse) {
   scoped_ptr<DataReductionProxyConfigServiceClient> config_client =
       BuildConfigClient();
   std::string config_data = config_client->ConstructStaticResponse();
@@ -49,4 +120,93 @@ TEST_F(DataReductionProxyConfigClientTest, TestConstructStaticResponse) {
   EXPECT_TRUE(config_parser::ParseClientConfig(config_data, &config));
 }
 
+TEST_F(DataReductionProxyConfigServiceClientTest, SuccessfulLoop) {
+  RequestOptionsPopulator populator(
+      base::Time::UnixEpoch() + base::TimeDelta::FromDays(1),
+      base::TimeDelta::FromDays(1));
+  SetDataReductionProxyEnabled(true);
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_CALL(*request_options(), PopulateConfigResponse(testing::_))
+      .Times(2)
+      .WillRepeatedly(
+          testing::Invoke(&populator,
+                          &RequestOptionsPopulator::PopulateResponse));
+  RunUntilIdle();
+  EXPECT_EQ(base::TimeDelta::FromDays(1), config_client()->GetDelay());
+  EXPECT_EQ(params()->origin().ToURI(), configurator()->origin());
+  EXPECT_EQ(params()->fallback_origin().ToURI(),
+            configurator()->fallback_origin());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  config_client()->SetNow(base::Time::UnixEpoch() + base::TimeDelta::FromDays(1)
+                          + base::TimeDelta::FromSeconds(5));
+  config_client()->RetrieveConfig();
+  EXPECT_EQ(base::TimeDelta::FromDays(1) - base::TimeDelta::FromSeconds(5),
+            config_client()->GetDelay());
+  EXPECT_EQ(params()->origin().ToURI(), configurator()->origin());
+  EXPECT_EQ(params()->fallback_origin().ToURI(),
+            configurator()->fallback_origin());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+}
+
+TEST_F(DataReductionProxyConfigServiceClientTest, SuccessfulLoopShortDuration) {
+  RequestOptionsPopulator populator(
+      base::Time::UnixEpoch() + base::TimeDelta::FromSeconds(1),
+      base::TimeDelta::FromSeconds(1));
+  SetDataReductionProxyEnabled(true);
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_CALL(*request_options(), PopulateConfigResponse(testing::_))
+      .Times(1)
+      .WillOnce(testing::Invoke(&populator,
+                                &RequestOptionsPopulator::PopulateResponse));
+  RunUntilIdle();
+  EXPECT_EQ(base::TimeDelta::FromSeconds(10), config_client()->GetDelay());
+  EXPECT_EQ(params()->origin().ToURI(), configurator()->origin());
+  EXPECT_EQ(params()->fallback_origin().ToURI(),
+            configurator()->fallback_origin());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+}
+
+TEST_F(DataReductionProxyConfigServiceClientTest, EnsureBackoff) {
+  SetDataReductionProxyEnabled(true);
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_CALL(*request_options(), PopulateConfigResponse(testing::_))
+      .Times(2)
+      .WillRepeatedly(testing::Invoke(&PopulateResponseFailure));
+  config_client()->RetrieveConfig();
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_EQ(base::TimeDelta::FromSeconds(20), config_client()->GetDelay());
+  config_client()->RetrieveConfig();
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_EQ(base::TimeDelta::FromSeconds(40), config_client()->GetDelay());
+}
+
+TEST_F(DataReductionProxyConfigServiceClientTest, ConfigDisabled) {
+  RequestOptionsPopulator populator(
+      base::Time::UnixEpoch() + base::TimeDelta::FromDays(1),
+      base::TimeDelta::FromDays(1));
+  SetDataReductionProxyEnabled(false);
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_CALL(*request_options(), PopulateConfigResponse(testing::_))
+      .Times(1)
+      .WillOnce(testing::Invoke(&populator,
+                                &RequestOptionsPopulator::PopulateResponse));
+  RunUntilIdle();
+  EXPECT_TRUE(configurator()->origin().empty());
+  EXPECT_TRUE(configurator()->fallback_origin().empty());
+  EXPECT_TRUE(configurator()->ssl_origin().empty());
+  EXPECT_EQ(base::TimeDelta::FromDays(1), config_client()->GetDelay());
+}
+
 }  // namespace data_reduction_proxy
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.cc
index 03676c9..f6e836c 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.cc
@@ -4,6 +4,7 @@
 
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h"
 
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h"
 #include "components/data_reduction_proxy/core/common/data_reduction_proxy_params_test_utils.h"
 #include "net/base/net_util.h"
 #include "net/url_request/test_url_fetcher_factory.h"
@@ -21,12 +22,28 @@ TestDataReductionProxyConfig::TestDataReductionProxyConfig(
     net::NetLog* net_log,
     DataReductionProxyConfigurator* configurator,
     DataReductionProxyEventStore* event_store)
-    : DataReductionProxyConfig(
-        task_runner, task_runner, net_log,
-        make_scoped_ptr(
-            new TestDataReductionProxyParams(params_flags, params_definitions))
-            .Pass(),
-        configurator, event_store) {
+    : TestDataReductionProxyConfig(
+          make_scoped_ptr(
+              new TestDataReductionProxyParams(params_flags,
+                                               params_definitions)).Pass(),
+          task_runner,
+          net_log,
+          configurator,
+          event_store) {
+}
+
+TestDataReductionProxyConfig::TestDataReductionProxyConfig(
+    scoped_ptr<DataReductionProxyConfigValues> config_values,
+    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+    net::NetLog* net_log,
+    DataReductionProxyConfigurator* configurator,
+    DataReductionProxyEventStore* event_store)
+    : DataReductionProxyConfig(task_runner,
+                               task_runner,
+                               net_log,
+                               config_values.Pass(),
+                               configurator,
+                               event_store) {
   network_interfaces_.reset(new net::NetworkInterfaceList());
 }
 
@@ -58,28 +75,30 @@ TestDataReductionProxyParams* TestDataReductionProxyConfig::test_params() {
   return static_cast<TestDataReductionProxyParams*>(config_values_.get());
 }
 
+DataReductionProxyConfigValues* TestDataReductionProxyConfig::config_values() {
+  return config_values_.get();
+}
+
 void TestDataReductionProxyConfig::SetStateForTest(
     bool enabled_by_user,
     bool alternative_enabled_by_user,
-    bool restricted_by_carrier,
-    bool at_startup) {
+    bool restricted_by_carrier) {
   enabled_by_user_ = enabled_by_user;
   alternative_enabled_by_user_ = alternative_enabled_by_user;
   restricted_by_carrier_ = restricted_by_carrier;
-  UpdateConfigurator(enabled_by_user_, alternative_enabled_by_user_,
-                     restricted_by_carrier_, at_startup);
 }
 
 MockDataReductionProxyConfig::MockDataReductionProxyConfig(
-    int params_flags,
-    unsigned int params_definitions,
+    scoped_ptr<DataReductionProxyConfigValues> config_values,
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
     net::NetLog* net_log,
     DataReductionProxyConfigurator* configurator,
     DataReductionProxyEventStore* event_store)
-    : TestDataReductionProxyConfig(
-        params_flags, params_definitions, task_runner, net_log, configurator,
-        event_store) {
+    : TestDataReductionProxyConfig(config_values.Pass(),
+                                   task_runner,
+                                   net_log,
+                                   configurator,
+                                   event_store) {
 }
 
 MockDataReductionProxyConfig::~MockDataReductionProxyConfig() {
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h
index 79c5548..fba88ee 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h
@@ -23,6 +23,7 @@ namespace data_reduction_proxy {
 
 class DataReductionProxyConfigurator;
 class DataReductionProxyEventStore;
+class DataReductionProxyMutableConfigValues;
 class TestDataReductionProxyParams;
 
 // Test version of |DataReductionProxyConfig|, which uses an underlying
@@ -39,6 +40,17 @@ class TestDataReductionProxyConfig : public DataReductionProxyConfig {
       net::NetLog* net_log,
       DataReductionProxyConfigurator* configurator,
       DataReductionProxyEventStore* event_store);
+
+  // Creates a |TestDataReductionProxyConfig| with the provided |config_values|.
+  // This permits any DataReductionProxyConfigValues to be used (such as
+  // DataReductionProxyParams or DataReductionProxyMutableConfigValues).
+  TestDataReductionProxyConfig(
+      scoped_ptr<DataReductionProxyConfigValues> config_values,
+      scoped_refptr<base::SingleThreadTaskRunner> task_runner,
+      net::NetLog* net_log,
+      DataReductionProxyConfigurator* configurator,
+      DataReductionProxyEventStore* event_store);
+
   ~TestDataReductionProxyConfig() override;
 
   void GetNetworkList(net::NetworkInterfaceList* interfaces,
@@ -53,11 +65,14 @@ class TestDataReductionProxyConfig : public DataReductionProxyConfig {
   // Retrieves the test params being used for the configuration.
   TestDataReductionProxyParams* test_params();
 
+  // Retrieves the underlying config values.
+  // TODO(jeremyim): Rationalize with test_params().
+  DataReductionProxyConfigValues* config_values();
+
   // Allows tests to set the internal state.
   void SetStateForTest(bool enabled_by_user,
                        bool alternative_enabled_by_user,
-                       bool restricted_by_carrier,
-                       bool at_startup);
+                       bool restricted_by_carrier);
 
   net::NetworkInterfaceList* interfaces() {
     return network_interfaces_.get();
@@ -71,10 +86,9 @@ class TestDataReductionProxyConfig : public DataReductionProxyConfig {
 // testing.
 class MockDataReductionProxyConfig : public TestDataReductionProxyConfig {
  public:
-  // Creates a |MockDataReductionProxyConfig| with the provided |params_flags|.
+  // Creates a |MockDataReductionProxyConfig|.
   MockDataReductionProxyConfig(
-      int params_flags,
-      unsigned int params_definitions,
+      scoped_ptr<DataReductionProxyConfigValues> config_values,
       scoped_refptr<base::SingleThreadTaskRunner> network_task_runner,
       net::NetLog* net_log,
       DataReductionProxyConfigurator* configurator,
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.cc
index 57b79f7..b957ab5 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.cc
@@ -10,9 +10,11 @@
 #include "base/single_thread_task_runner.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_bypass_protocol.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_configurator.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_delegate.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_interceptor.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_service.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_settings.h"
@@ -46,12 +48,32 @@ DataReductionProxyIOData::DataReductionProxyIOData(
   event_store_.reset(new DataReductionProxyEventStore(ui_task_runner));
   configurator_.reset(new DataReductionProxyConfigurator(
       io_task_runner, net_log, event_store_.get()));
-  config_.reset(new DataReductionProxyConfig(
-      io_task_runner_, ui_task_runner_, net_log, params.Pass(),
-      configurator_.get(), event_store_.get()));
+  bool use_config_client = DataReductionProxyParams::IsConfigClientEnabled();
+  DataReductionProxyMutableConfigValues* raw_mutable_config = nullptr;
+  if (use_config_client) {
+    scoped_ptr<DataReductionProxyMutableConfigValues> mutable_config =
+        DataReductionProxyMutableConfigValues::CreateFromParams(io_task_runner_,
+                                                                params.get());
+    raw_mutable_config = mutable_config.get();
+    config_.reset(new DataReductionProxyConfig(
+        io_task_runner_, ui_task_runner_, net_log, mutable_config.Pass(),
+        configurator_.get(), event_store_.get()));
+  } else {
+    config_.reset(new DataReductionProxyConfig(
+        io_task_runner_, ui_task_runner_, net_log, params.Pass(),
+        configurator_.get(), event_store_.get()));
+  }
+
   request_options_.reset(new DataReductionProxyRequestOptions(
       client_, config_.get(), io_task_runner_));
   request_options_->Init();
+
+  if (use_config_client) {
+    config_client_.reset(new DataReductionProxyConfigServiceClient(
+        params.Pass(), GetBackoffPolicy(), request_options_.get(),
+        raw_mutable_config, config_.get(), io_task_runner_));
+  }
+
   proxy_delegate_.reset(
       new DataReductionProxyDelegate(request_options_.get(), config_.get()));
  }
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h
index 0403c0a..ff0967b 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h
@@ -21,6 +21,7 @@ class URLRequestInterceptor;
 namespace data_reduction_proxy {
 
 class DataReductionProxyConfig;
+class DataReductionProxyConfigServiceClient;
 class DataReductionProxyConfigurator;
 class DataReductionProxyEventStore;
 class DataReductionProxyService;
@@ -150,6 +151,9 @@ class DataReductionProxyIOData {
   // Constructs credentials suitable for authenticating the client.
   scoped_ptr<DataReductionProxyRequestOptions> request_options_;
 
+  // Requests new Data Reduction Proxy configurations from a remote service.
+  scoped_ptr<DataReductionProxyConfigServiceClient> config_client_;
+
   // A net log.
   net::NetLog* net_log_;
 
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.cc
new file mode 100644
index 0000000..cebbdaca
--- /dev/null
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.cc
@@ -0,0 +1,140 @@
+// Copyright 2015 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 "components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h"
+
+#include "base/single_thread_task_runner.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
+
+namespace data_reduction_proxy {
+
+scoped_ptr<DataReductionProxyMutableConfigValues>
+DataReductionProxyMutableConfigValues::CreateFromParams(
+    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
+    const DataReductionProxyParams* params) {
+  scoped_ptr<DataReductionProxyMutableConfigValues> config_values(
+      new DataReductionProxyMutableConfigValues(io_task_runner));
+  config_values->promo_allowed_ = params->promo_allowed();
+  config_values->holdback_ = params->holdback();
+  config_values->allowed_ = params->allowed();
+  config_values->fallback_allowed_ = params->fallback_allowed();
+  config_values->secure_proxy_check_url_ = params->secure_proxy_check_url();
+  return config_values.Pass();
+}
+
+DataReductionProxyMutableConfigValues::DataReductionProxyMutableConfigValues(
+    scoped_refptr<base::SingleThreadTaskRunner> io_task_runner)
+    : empty_origin_(),
+      promo_allowed_(false),
+      holdback_(false),
+      allowed_(false),
+      fallback_allowed_(false),
+      origin_(empty_origin_),
+      fallback_origin_(empty_origin_),
+      io_task_runner_(io_task_runner) {
+  DCHECK(io_task_runner.get());
+}
+
+DataReductionProxyMutableConfigValues::
+    ~DataReductionProxyMutableConfigValues() {
+}
+
+bool DataReductionProxyMutableConfigValues::promo_allowed() const {
+  return promo_allowed_;
+}
+
+bool DataReductionProxyMutableConfigValues::holdback() const {
+  return holdback_;
+}
+
+bool DataReductionProxyMutableConfigValues::allowed() const {
+  return allowed_;
+}
+
+bool DataReductionProxyMutableConfigValues::fallback_allowed() const {
+  return fallback_allowed_;
+}
+
+bool DataReductionProxyMutableConfigValues::alternative_allowed() const {
+  return false;
+}
+
+bool DataReductionProxyMutableConfigValues::alternative_fallback_allowed()
+    const {
+  return false;
+}
+
+bool DataReductionProxyMutableConfigValues::UsingHTTPTunnel(
+    const net::HostPortPair& proxy_server) const {
+  return false;
+}
+
+bool DataReductionProxyMutableConfigValues::IsDataReductionProxy(
+    const net::HostPortPair& host_port_pair,
+    DataReductionProxyTypeInfo* proxy_info) const {
+  // TODO(jeremyim): Rework as part of ConfigValues interface changes.
+  if (allowed() && origin().is_valid() &&
+      origin().host_port_pair().Equals(host_port_pair)) {
+    if (proxy_info) {
+      proxy_info->proxy_servers.first = origin();
+      if (fallback_allowed())
+        proxy_info->proxy_servers.second = fallback_origin();
+    }
+    return true;
+  }
+
+  if (!fallback_allowed() || !fallback_origin().is_valid() ||
+      !fallback_origin().host_port_pair().Equals(host_port_pair))
+    return false;
+
+  if (proxy_info) {
+    proxy_info->proxy_servers.first = fallback_origin();
+    proxy_info->proxy_servers.second = net::ProxyServer::FromURI(
+        std::string(), net::ProxyServer::SCHEME_HTTP);
+    proxy_info->is_fallback = true;
+  }
+
+  return true;
+}
+
+const net::ProxyServer& DataReductionProxyMutableConfigValues::origin() const {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+  return origin_;
+}
+
+const net::ProxyServer& DataReductionProxyMutableConfigValues::fallback_origin()
+    const {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+  return fallback_origin_;
+}
+
+const net::ProxyServer& DataReductionProxyMutableConfigValues::alt_origin()
+    const {
+  return empty_origin_;
+}
+
+const net::ProxyServer&
+DataReductionProxyMutableConfigValues::alt_fallback_origin() const {
+  return empty_origin_;
+}
+
+const net::ProxyServer& DataReductionProxyMutableConfigValues::ssl_origin()
+    const {
+  return empty_origin_;
+}
+
+const GURL& DataReductionProxyMutableConfigValues::secure_proxy_check_url()
+    const {
+  return secure_proxy_check_url_;
+}
+
+void DataReductionProxyMutableConfigValues::UpdateValues(
+    const net::ProxyServer& origin,
+    const net::ProxyServer& fallback_origin) {
+  DCHECK(io_task_runner_->BelongsToCurrentThread());
+  origin_ = origin;
+  fallback_origin_ = fallback_origin;
+}
+
+}  // namespace data_reduction_proxy
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h
new file mode 100644
index 0000000..6897cb9
--- /dev/null
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h
@@ -0,0 +1,81 @@
+// Copyright 2015 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.
+
+#ifndef COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_MUTABLE_CONFIG_VALUES_H_
+#define COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_MUTABLE_CONFIG_VALUES_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_config_values.h"
+#include "net/proxy/proxy_server.h"
+#include "url/gurl.h"
+
+namespace base {
+class SingleThreadTaskRunner;
+}
+
+namespace data_reduction_proxy {
+
+class DataReductionProxyParams;
+
+// A |DataReductionProxyConfigValues| which is permitted to change its
+// underlying values via the UpdateValues method.
+class DataReductionProxyMutableConfigValues
+    : public DataReductionProxyConfigValues {
+ public:
+  // Creates a new |DataReductionProxyMutableConfigValues| using |params| as
+  // the basis for its initial values.
+  static scoped_ptr<DataReductionProxyMutableConfigValues> CreateFromParams(
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner,
+      const DataReductionProxyParams* params);
+
+  ~DataReductionProxyMutableConfigValues() override;
+
+  // Updates |origin_| and  |fallback_origin_| with the provided values.
+  // Virtual for testing.
+  virtual void UpdateValues(const net::ProxyServer& origin,
+                            const net::ProxyServer& fallback_origin);
+
+  // Overrides of |DataReductionProxyConfigValues|
+  bool promo_allowed() const override;
+  bool holdback() const override;
+  bool allowed() const override;
+  bool fallback_allowed() const override;
+  bool alternative_allowed() const override;
+  bool alternative_fallback_allowed() const override;
+  bool UsingHTTPTunnel(const net::HostPortPair& proxy_server) const override;
+  bool IsDataReductionProxy(
+      const net::HostPortPair& host_port_pair,
+      DataReductionProxyTypeInfo* proxy_info) const override;
+  const net::ProxyServer& origin() const override;
+  const net::ProxyServer& fallback_origin() const override;
+  const net::ProxyServer& alt_origin() const override;
+  const net::ProxyServer& alt_fallback_origin() const override;
+  const net::ProxyServer& ssl_origin() const override;
+  const GURL& secure_proxy_check_url() const override;
+
+ protected:
+  DataReductionProxyMutableConfigValues(
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
+
+ private:
+  net::ProxyServer empty_origin_;
+  bool promo_allowed_;
+  bool holdback_;
+  bool allowed_;
+  bool fallback_allowed_;
+  net::ProxyServer origin_;
+  net::ProxyServer fallback_origin_;
+  GURL secure_proxy_check_url_;
+
+  // |io_task_runner_| should be the task runner for running operations on the
+  // IO thread.
+  scoped_refptr<base::SingleThreadTaskRunner> io_task_runner_;
+
+  DISALLOW_COPY_AND_ASSIGN(DataReductionProxyMutableConfigValues);
+};
+
+}  // namespace data_reduction_proxy
+#endif  // COMPONENTS_DATA_REDUCTION_PROXY_CORE_BROWSER_DATA_REDUCTION_PROXY_MUTABLE_CONFIG_VALUES_H_
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
index 675b05c..1b95890 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.cc
@@ -99,6 +99,7 @@ DataReductionProxyRequestOptions::DataReductionProxyRequestOptions(
     DataReductionProxyConfig* config,
     scoped_refptr<base::SingleThreadTaskRunner> network_task_runner)
     : client_(GetString(client)),
+      use_assigned_credentials_(false),
       data_reduction_proxy_config_(config),
       network_task_runner_(network_task_runner) {
   GetChromiumBuildAndPatch(ChromiumVersion(), &build_, &patch_);
@@ -110,6 +111,7 @@ DataReductionProxyRequestOptions::DataReductionProxyRequestOptions(
     DataReductionProxyConfig* config,
     scoped_refptr<base::SingleThreadTaskRunner> network_task_runner)
     : client_(GetString(client)),
+      use_assigned_credentials_(false),
       data_reduction_proxy_config_(config),
       network_task_runner_(network_task_runner) {
   GetChromiumBuildAndPatch(version, &build_, &patch_);
@@ -227,7 +229,7 @@ void DataReductionProxyRequestOptions::SetHeader(
     net::HttpRequestHeaders* headers) {
   base::Time now = Now();
   // Authorization credentials must be regenerated if they are expired.
-  if (now > credentials_expiration_time_)
+  if (!use_assigned_credentials_ && (now > credentials_expiration_time_))
     UpdateCredentials();
   UpdateLoFi();
   const char kChromeProxyHeader[] = "Chrome-Proxy";
@@ -264,8 +266,6 @@ void DataReductionProxyRequestOptions::ComputeCredentials(
 }
 
 void DataReductionProxyRequestOptions::UpdateCredentials() {
-  std::string session;
-  std::string credentials;
   base::Time now = Now();
   ComputeCredentials(now, &session_, &credentials_);
   credentials_expiration_time_ = now + base::TimeDelta::FromHours(24);
@@ -293,6 +293,18 @@ void DataReductionProxyRequestOptions::PopulateConfigResponse(
                       config_parser::TimeToISO8601(expiration_time));
 }
 
+void DataReductionProxyRequestOptions::SetCredentials(
+    const std::string& session,
+    const std::string& credentials) {
+  DCHECK(network_task_runner_->BelongsToCurrentThread());
+  session_ = session;
+  credentials_ = credentials;
+  // Force skipping of credential regeneration. It should be handled by the
+  // caller.
+  use_assigned_credentials_ = true;
+  RegenerateRequestHeaderValue();
+}
+
 std::string DataReductionProxyRequestOptions::GetDefaultKey() const {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h
index 5a0b3b0..8d6c289 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h
@@ -125,6 +125,10 @@ class DataReductionProxyRequestOptions {
   // Virtualized for testing.
   virtual void PopulateConfigResponse(base::DictionaryValue* response) const;
 
+  // Sets the credentials for sending to the Data Reduction Proxy.
+  void SetCredentials(const std::string& session,
+                      const std::string& credentials);
+
  protected:
   void SetHeader(net::HttpRequestHeaders* headers);
 
@@ -211,6 +215,10 @@ class DataReductionProxyRequestOptions {
   // never used for more than twenty-four hours.
   base::Time credentials_expiration_time_;
 
+  // Whether the authentication headers are sourced by |this| or injected via
+  // |SetCredentials|.
+  bool use_assigned_credentials_;
+
   DataReductionProxyConfig* data_reduction_proxy_config_;
 
   scoped_refptr<base::SingleThreadTaskRunner> network_task_runner_;
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_settings_unittest.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_settings_unittest.cc
index 7e73e60..fe091dc 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_settings_unittest.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_settings_unittest.cc
@@ -45,7 +45,7 @@ class DataReductionProxySettingsTest
     test_context_->pref_service()->SetBoolean(prefs::kDataReductionProxyEnabled,
                                               initially_enabled);
     test_context_->config()->SetStateForTest(initially_enabled, false,
-                                             !request_succeeded, false);
+                                             !request_succeeded);
     ExpectSetProxyPrefs(expected_enabled, false, false);
     settings_->MaybeActivateDataReductionProxy(false);
     test_context_->RunUntilIdle();
@@ -55,7 +55,7 @@ class DataReductionProxySettingsTest
 TEST_F(DataReductionProxySettingsTest, TestIsProxyEnabledOrManaged) {
   settings_->InitPrefMembers();
   // The proxy is disabled initially.
-  test_context_->config()->SetStateForTest(false, false, false, false);
+  test_context_->config()->SetStateForTest(false, false, false);
 
   EXPECT_FALSE(settings_->IsDataReductionProxyEnabled());
   EXPECT_FALSE(settings_->IsDataReductionProxyManaged());
@@ -74,7 +74,7 @@ TEST_F(DataReductionProxySettingsTest, TestIsProxyEnabledOrManaged) {
 TEST_F(DataReductionProxySettingsTest, TestCanUseDataReductionProxy) {
   settings_->InitPrefMembers();
   // The proxy is disabled initially.
-  test_context_->config()->SetStateForTest(false, false, false, false);
+  test_context_->config()->SetStateForTest(false, false, false);
 
   GURL http_gurl("http://url.com/");
   EXPECT_FALSE(settings_->CanUseDataReductionProxy(http_gurl));
@@ -240,7 +240,7 @@ TEST(DataReductionProxySettingsStandaloneTest, TestOnProxyEnabledPrefChange) {
           .Build();
 
   // The proxy is enabled initially.
-  drp_test_context->config()->SetStateForTest(true, false, false, true);
+  drp_test_context->config()->SetStateForTest(true, false, false);
   drp_test_context->InitSettings();
 
   // The pref is disabled, so correspondingly should be the proxy.
@@ -269,7 +269,7 @@ TEST_F(DataReductionProxySettingsTest, TestMaybeActivateDataReductionProxy) {
 
   // TODO(bengr): Test enabling/disabling while a secure proxy check is
   // outstanding.
-  // The proxy is enabled and unrestructed initially.
+  // The proxy is enabled and unrestricted initially.
   // Request succeeded but with bad response, expect proxy to be restricted.
   CheckMaybeActivateDataReductionProxy(true, true, true, true, false);
   // Request succeeded with valid response, expect proxy to be unrestricted.
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
index e9ea65ee..aae60c3 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.cc
@@ -6,9 +6,11 @@
 
 #include "base/message_loop/message_loop.h"
 #include "base/prefs/testing_pref_service.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_configurator_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_interceptor.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_mutable_config_values.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_network_delegate.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_prefs.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_settings.h"
@@ -26,6 +28,16 @@ namespace {
 
 const char kTestKey[] = "test-key";
 
+const net::BackoffEntry::Policy kTestBackoffPolicy = {
+    0,               // num_errors_to_ignore
+    10 * 1000,       // initial_delay_ms
+    2,               // multiply_factor
+    0,               // jitter_factor
+    30 * 60 * 1000,  // maximum_backoff_ms
+    -1,              // entry_lifetime_ms
+    true,            // always_use_initial_delay
+};
+
 }  // namespace
 
 namespace data_reduction_proxy {
@@ -71,6 +83,82 @@ MockDataReductionProxyRequestOptions::MockDataReductionProxyRequestOptions(
 MockDataReductionProxyRequestOptions::~MockDataReductionProxyRequestOptions() {
 }
 
+TestDataReductionProxyConfigServiceClient::
+    TestDataReductionProxyConfigServiceClient(
+        scoped_ptr<DataReductionProxyParams> params,
+        DataReductionProxyRequestOptions* request_options,
+        DataReductionProxyMutableConfigValues* config_values,
+        DataReductionProxyConfig* config,
+        scoped_refptr<base::SingleThreadTaskRunner> io_task_runner)
+    : DataReductionProxyConfigServiceClient(params.Pass(),
+                                            kTestBackoffPolicy,
+                                            request_options,
+                                            config_values,
+                                            config,
+                                            io_task_runner),
+      tick_clock_(base::Time::UnixEpoch()),
+      test_backoff_entry_(&kTestBackoffPolicy, &tick_clock_) {
+}
+
+TestDataReductionProxyConfigServiceClient::
+    ~TestDataReductionProxyConfigServiceClient() {
+}
+
+void TestDataReductionProxyConfigServiceClient::SetNow(const base::Time& time) {
+  tick_clock_.SetTime(time);
+}
+
+void TestDataReductionProxyConfigServiceClient::SetCustomReleaseTime(
+    const base::TimeTicks& release_time) {
+  test_backoff_entry_.SetCustomReleaseTime(release_time);
+}
+
+base::TimeDelta TestDataReductionProxyConfigServiceClient::GetDelay() const {
+  return config_refresh_timer_.GetCurrentDelay();
+}
+
+base::Time TestDataReductionProxyConfigServiceClient::Now() const {
+  return tick_clock_.Now();
+}
+
+net::BackoffEntry*
+TestDataReductionProxyConfigServiceClient::GetBackoffEntry() {
+  return &test_backoff_entry_;
+}
+
+TestDataReductionProxyConfigServiceClient::TestTickClock::TestTickClock(
+    const base::Time& initial_time)
+    : time_(initial_time) {
+}
+
+base::TimeTicks
+TestDataReductionProxyConfigServiceClient::TestTickClock::NowTicks() const {
+  return base::TimeTicks::UnixEpoch() + (time_ - base::Time::UnixEpoch());
+}
+
+base::Time
+TestDataReductionProxyConfigServiceClient::TestTickClock::Now() const {
+  return time_;
+}
+
+void TestDataReductionProxyConfigServiceClient::TestTickClock::SetTime(
+    const base::Time& time) {
+  time_ = time;
+}
+
+TestDataReductionProxyConfigServiceClient::TestBackoffEntry::TestBackoffEntry(
+    const net::BackoffEntry::Policy* const policy,
+    const TestTickClock* tick_clock)
+    : net::BackoffEntry(policy),
+      tick_clock_(tick_clock) {
+}
+
+base::TimeTicks
+TestDataReductionProxyConfigServiceClient::TestBackoffEntry::ImplGetTimeNow()
+    const {
+  return tick_clock_->NowTicks();
+}
+
 MockDataReductionProxyService::MockDataReductionProxyService(
     scoped_ptr<DataReductionProxyStatisticsPrefs> statistics_prefs,
     DataReductionProxySettings* settings,
@@ -84,10 +172,11 @@ MockDataReductionProxyService::~MockDataReductionProxyService() {
 
 TestDataReductionProxyIOData::TestDataReductionProxyIOData(
     scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-    scoped_ptr<TestDataReductionProxyConfig> config,
+    scoped_ptr<DataReductionProxyConfig> config,
     scoped_ptr<DataReductionProxyEventStore> event_store,
     scoped_ptr<DataReductionProxyRequestOptions> request_options,
-    scoped_ptr<DataReductionProxyConfigurator> configurator)
+    scoped_ptr<DataReductionProxyConfigurator> configurator,
+    scoped_ptr<DataReductionProxyConfigServiceClient> config_client)
     : DataReductionProxyIOData() {
   io_task_runner_ = task_runner;
   ui_task_runner_ = task_runner;
@@ -95,6 +184,7 @@ TestDataReductionProxyIOData::TestDataReductionProxyIOData(
   event_store_ = event_store.Pass();
   request_options_ = request_options.Pass();
   configurator_ = configurator.Pass();
+  config_client_ = config_client.Pass();
   io_task_runner_ = task_runner;
   ui_task_runner_ = task_runner;
 }
@@ -113,6 +203,8 @@ DataReductionProxyTestContext::Builder::Builder()
       use_test_configurator_(false),
       use_mock_service_(false),
       use_mock_request_options_(false),
+      use_config_client_(false),
+      use_test_config_client_(false),
       skip_settings_initialization_(false) {
 }
 
@@ -174,6 +266,19 @@ DataReductionProxyTestContext::Builder::WithMockRequestOptions() {
 }
 
 DataReductionProxyTestContext::Builder&
+DataReductionProxyTestContext::Builder::WithConfigClient() {
+  use_config_client_ = true;
+  return *this;
+}
+
+DataReductionProxyTestContext::Builder&
+DataReductionProxyTestContext::Builder::WithTestConfigClient() {
+  use_config_client_ = true;
+  use_test_config_client_ = true;
+  return *this;
+}
+
+DataReductionProxyTestContext::Builder&
 DataReductionProxyTestContext::Builder::SkipSettingsInitialization() {
   skip_settings_initialization_ = true;
   return *this;
@@ -181,6 +286,8 @@ DataReductionProxyTestContext::Builder::SkipSettingsInitialization() {
 
 scoped_ptr<DataReductionProxyTestContext>
 DataReductionProxyTestContext::Builder::Build() {
+  // Check for invalid builder combinations.
+  DCHECK(!(use_mock_config_ && use_config_client_));
   scoped_ptr<base::MessageLoopForIO> loop(new base::MessageLoopForIO());
 
   unsigned int test_context_flags = 0;
@@ -216,15 +323,29 @@ DataReductionProxyTestContext::Builder::Build() {
   }
 
   scoped_ptr<TestDataReductionProxyConfig> config;
-  if (use_mock_config_) {
+  scoped_ptr<DataReductionProxyConfigServiceClient> config_client;
+  DataReductionProxyMutableConfigValues* raw_mutable_config = nullptr;
+  scoped_ptr<TestDataReductionProxyParams> params(
+      new TestDataReductionProxyParams(params_flags_, params_definitions_));
+  TestDataReductionProxyParams* raw_params = params.get();
+  if (use_config_client_) {
+    test_context_flags |= USE_CONFIG_CLIENT;
+    scoped_ptr<DataReductionProxyMutableConfigValues> mutable_config =
+        DataReductionProxyMutableConfigValues::CreateFromParams(task_runner,
+                                                                params.get());
+    raw_mutable_config = mutable_config.get();
+    config.reset(new TestDataReductionProxyConfig(
+        mutable_config.Pass(), task_runner, net_log.get(), configurator.get(),
+        event_store.get()));
+  } else if (use_mock_config_) {
     test_context_flags |= USE_MOCK_CONFIG;
     config.reset(new MockDataReductionProxyConfig(
-        params_flags_, params_definitions_, task_runner, net_log.get(),
-        configurator.get(), event_store.get()));
+        params.Pass(), task_runner, net_log.get(), configurator.get(),
+        event_store.get()));
   } else {
     config.reset(new TestDataReductionProxyConfig(
-        params_flags_, params_definitions_, task_runner, net_log.get(),
-        configurator.get(), event_store.get()));
+        params.Pass(), task_runner, net_log.get(), configurator.get(),
+        event_store.get()));
   }
 
   scoped_ptr<DataReductionProxyRequestOptions> request_options;
@@ -237,6 +358,17 @@ DataReductionProxyTestContext::Builder::Build() {
         client_, config.get(), task_runner));
   }
 
+  if (use_test_config_client_) {
+    test_context_flags |= USE_TEST_CONFIG_CLIENT;
+    config_client.reset(new TestDataReductionProxyConfigServiceClient(
+        params.Pass(), request_options.get(), raw_mutable_config, config.get(),
+        task_runner));
+  } else if (use_config_client_) {
+    config_client.reset(new DataReductionProxyConfigServiceClient(
+        params.Pass(), GetBackoffPolicy(), request_options.get(),
+        raw_mutable_config, config.get(), task_runner));
+  }
+
   scoped_ptr<DataReductionProxySettings> settings(
       new DataReductionProxySettings());
   if (skip_settings_initialization_)
@@ -250,14 +382,14 @@ DataReductionProxyTestContext::Builder::Build() {
   scoped_ptr<TestDataReductionProxyIOData> io_data(
       new TestDataReductionProxyIOData(
           task_runner, config.Pass(), event_store.Pass(),
-          request_options.Pass(), configurator.Pass()));
+          request_options.Pass(), configurator.Pass(), config_client.Pass()));
   io_data->InitOnUIThread(pref_service.get());
 
   scoped_ptr<DataReductionProxyTestContext> test_context(
       new DataReductionProxyTestContext(
           loop.Pass(), task_runner, pref_service.Pass(), net_log.Pass(),
           request_context_getter, mock_socket_factory_, io_data.Pass(),
-          settings.Pass(), test_context_flags));
+          settings.Pass(), raw_params, test_context_flags));
 
   if (!skip_settings_initialization_)
     test_context->InitSettingsWithoutCheck();
@@ -274,6 +406,7 @@ DataReductionProxyTestContext::DataReductionProxyTestContext(
     net::MockClientSocketFactory* mock_socket_factory,
     scoped_ptr<TestDataReductionProxyIOData> io_data,
     scoped_ptr<DataReductionProxySettings> settings,
+    TestDataReductionProxyParams* params,
     unsigned int test_context_flags)
     : test_context_flags_(test_context_flags),
       loop_(loop.Pass()),
@@ -283,7 +416,8 @@ DataReductionProxyTestContext::DataReductionProxyTestContext(
       request_context_getter_(request_context_getter),
       mock_socket_factory_(mock_socket_factory),
       io_data_(io_data.Pass()),
-      settings_(settings.Pass()) {
+      settings_(settings.Pass()),
+      params_(params) {
 }
 
 DataReductionProxyTestContext::~DataReductionProxyTestContext() {
@@ -413,6 +547,26 @@ DataReductionProxyTestContext::mock_request_options() const {
       io_data_->request_options());
 }
 
+TestDataReductionProxyConfig* DataReductionProxyTestContext::config() const {
+  return reinterpret_cast<TestDataReductionProxyConfig*>(io_data_->config());
+}
+
+DataReductionProxyMutableConfigValues*
+DataReductionProxyTestContext::mutable_config_values() {
+  DCHECK(test_context_flags_ &
+         DataReductionProxyTestContext::USE_CONFIG_CLIENT);
+  return reinterpret_cast<DataReductionProxyMutableConfigValues*>(
+      config()->config_values());
+}
+
+TestDataReductionProxyConfigServiceClient*
+DataReductionProxyTestContext::test_config_client() {
+  DCHECK(test_context_flags_ &
+         DataReductionProxyTestContext::USE_TEST_CONFIG_CLIENT);
+  return reinterpret_cast<TestDataReductionProxyConfigServiceClient*>(
+      io_data_->config_client());
+}
+
 DataReductionProxyUsageStats::UnreachableCallback
 DataReductionProxyTestContext::unreachable_callback() const {
   return base::Bind(&DataReductionProxySettings::SetUnreachable,
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h
index 9e0695ef..df1b2c0 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_test_utils.h
@@ -12,11 +12,13 @@
 #include "base/memory/scoped_ptr.h"
 #include "base/single_thread_task_runner.h"
 #include "base/time/time.h"
+#include "components/data_reduction_proxy/core/browser/data_reduction_proxy_config_service_client.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_io_data.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_request_options.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_service.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_settings_test_utils.h"
 #include "components/data_reduction_proxy/core/browser/data_reduction_proxy_usage_stats.h"
+#include "net/base/backoff_entry.h"
 #include "net/base/capturing_net_log.h"
 #include "testing/gmock/include/gmock/gmock.h"
 
@@ -38,12 +40,14 @@ namespace data_reduction_proxy {
 
 class DataReductionProxyConfigurator;
 class DataReductionProxyEventStore;
+class DataReductionProxyMutableConfigValues;
 class DataReductionProxyRequestOptions;
 class DataReductionProxySettings;
 class DataReductionProxyStatisticsPrefs;
 class MockDataReductionProxyConfig;
 class TestDataReductionProxyConfig;
 class TestDataReductionProxyConfigurator;
+class TestDataReductionProxyParams;
 
 // Test version of |DataReductionProxyRequestOptions|.
 class TestDataReductionProxyRequestOptions
@@ -83,6 +87,69 @@ class MockDataReductionProxyRequestOptions
                      void(base::DictionaryValue* response));
 };
 
+// Test version of |DataReductionProxyConfigServiceClient|, which permits
+// finely controlling the backoff timer.
+class TestDataReductionProxyConfigServiceClient
+    : public DataReductionProxyConfigServiceClient {
+ public:
+  TestDataReductionProxyConfigServiceClient(
+      scoped_ptr<DataReductionProxyParams> params,
+      DataReductionProxyRequestOptions* request_options,
+      DataReductionProxyMutableConfigValues* config_values,
+      DataReductionProxyConfig* config,
+      scoped_refptr<base::SingleThreadTaskRunner> io_task_runner);
+
+  ~TestDataReductionProxyConfigServiceClient() override;
+
+  void SetNow(const base::Time& time);
+
+  void SetCustomReleaseTime(const base::TimeTicks& release_time);
+
+  base::TimeDelta GetDelay() const;
+
+ protected:
+  // Overrides of DataReductionProxyConfigServiceClient
+  base::Time Now() const override;
+  net::BackoffEntry* GetBackoffEntry() override;
+
+ private:
+  // A clock which returns a fixed value in both base::Time and base::TimeTicks.
+  class TestTickClock {
+   public:
+    TestTickClock(const base::Time& initial_time);
+
+    // Returns the current base::TimeTicks
+    base::TimeTicks NowTicks() const;
+
+    // Returns the current base::Time
+    base::Time Now() const;
+
+    // Sets the current time.
+    void SetTime(const base::Time& time);
+
+   private:
+    base::Time time_;
+  };
+
+  // A net::BackoffEntry which uses an injected base::TickClock to control
+  // the backoff expiration time.
+  class TestBackoffEntry : public net::BackoffEntry {
+   public:
+    TestBackoffEntry(const BackoffEntry::Policy* const policy,
+                     const TestTickClock* tick_clock);
+
+   protected:
+    // Override of net::BackoffEntry.
+    base::TimeTicks ImplGetTimeNow() const override;
+
+   private:
+    const TestTickClock* tick_clock_;
+  };
+
+  TestTickClock tick_clock_;
+  TestBackoffEntry test_backoff_entry_;
+};
+
 // Test version of |DataReductionProxyService|, which permits mocking of various
 // methods.
 class MockDataReductionProxyService : public DataReductionProxyService {
@@ -105,15 +172,20 @@ class TestDataReductionProxyIOData : public DataReductionProxyIOData {
  public:
   TestDataReductionProxyIOData(
       scoped_refptr<base::SingleThreadTaskRunner> task_runner,
-      scoped_ptr<TestDataReductionProxyConfig> config,
+      scoped_ptr<DataReductionProxyConfig> config,
       scoped_ptr<DataReductionProxyEventStore> event_store,
       scoped_ptr<DataReductionProxyRequestOptions> request_options,
-      scoped_ptr<DataReductionProxyConfigurator> configurator);
+      scoped_ptr<DataReductionProxyConfigurator> configurator,
+      scoped_ptr<DataReductionProxyConfigServiceClient> config_client);
   ~TestDataReductionProxyIOData() override;
 
   DataReductionProxyConfigurator* configurator() const {
     return configurator_.get();
   }
+
+  DataReductionProxyConfigServiceClient* config_client() const {
+    return config_client_.get();
+  }
 };
 
 // Builds a test version of the Data Reduction Proxy stack for use in tests.
@@ -165,6 +237,13 @@ class DataReductionProxyTestContext {
     // |DataReductionProxyRequestOptions|.
     Builder& WithMockRequestOptions();
 
+    // Specifies the use of the |DataReductionProxyConfigServiceClient|.
+    Builder& WithConfigClient();
+
+    // Specifies the use of the a |TestDataReductionProxyConfigServiceClient|
+    // instead of a |DataReductionProxyConfigServiceClient|.
+    Builder& WithTestConfigClient();
+
     // Construct, but do not initialize the |DataReductionProxySettings| object.
     Builder& SkipSettingsInitialization();
 
@@ -182,6 +261,8 @@ class DataReductionProxyTestContext {
     bool use_test_configurator_;
     bool use_mock_service_;
     bool use_mock_request_options_;
+    bool use_config_client_;
+    bool use_test_config_client_;
     bool skip_settings_initialization_;
   };
 
@@ -231,6 +312,17 @@ class DataReductionProxyTestContext {
   // only be called if built with WithMockRequestOptions.
   MockDataReductionProxyRequestOptions* mock_request_options() const;
 
+  // Returns the underlying |TestDataReductionProxyConfig|.
+  TestDataReductionProxyConfig* config() const;
+
+  // Returns the underlying |DataReductionProxyMutableConfigValues|. This can
+  // only be called if built with WithConfigClient.
+  DataReductionProxyMutableConfigValues* mutable_config_values();
+
+  // Returns the underlying |TestDataReductionProxyConfigServiceClient|. This
+  // can only be called if built with WithTestConfigClient.
+  TestDataReductionProxyConfigServiceClient* test_config_client();
+
   // Obtains a callback for notifying that the Data Reduction Proxy is no
   // longer reachable.
   DataReductionProxyUsageStats::UnreachableCallback
@@ -260,10 +352,6 @@ class DataReductionProxyTestContext {
     return io_data_->configurator();
   }
 
-  TestDataReductionProxyConfig* config() const {
-    return reinterpret_cast<TestDataReductionProxyConfig*>(io_data_->config());
-  }
-
   TestDataReductionProxyIOData* io_data() const {
     return io_data_.get();
   }
@@ -272,6 +360,10 @@ class DataReductionProxyTestContext {
     return settings_.get();
   }
 
+  TestDataReductionProxyParams* test_params() const {
+    return params_;
+  }
+
  private:
   enum TestContextOptions {
     // Permits mocking of the underlying |DataReductionProxyConfig|.
@@ -287,6 +379,10 @@ class DataReductionProxyTestContext {
     USE_MOCK_SERVICE = 0x8,
     // Permits mocking of the underlying |DataReductionProxyRequestOptions|.
     USE_MOCK_REQUEST_OPTIONS = 0x10,
+    // Specifies the use of the |DataReductionProxyConfigServiceClient|.
+    USE_CONFIG_CLIENT = 0x20,
+    // Specifies the use of the |TESTDataReductionProxyConfigServiceClient|.
+    USE_TEST_CONFIG_CLIENT = 0x40,
   };
 
   DataReductionProxyTestContext(
@@ -298,6 +394,7 @@ class DataReductionProxyTestContext {
       net::MockClientSocketFactory* mock_socket_factory,
       scoped_ptr<TestDataReductionProxyIOData> io_data,
       scoped_ptr<DataReductionProxySettings> settings,
+      TestDataReductionProxyParams* params,
       unsigned int test_context_flags);
 
   void InitSettingsWithoutCheck();
@@ -320,6 +417,8 @@ class DataReductionProxyTestContext {
   scoped_ptr<TestDataReductionProxyIOData> io_data_;
   scoped_ptr<DataReductionProxySettings> settings_;
 
+  TestDataReductionProxyParams* params_;
+
   DISALLOW_COPY_AND_ASSIGN(DataReductionProxyTestContext);
 };
 
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.cc b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.cc
index 3769f3a..79205a2 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.cc
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.cc
@@ -130,6 +130,12 @@ std::string DataReductionProxyParams::GetQuicFieldTrialName() {
   return kQuicFieldTrial;
 }
 
+// static
+bool DataReductionProxyParams::IsConfigClientEnabled() {
+  return base::CommandLine::ForCurrentProcess()->HasSwitch(
+      data_reduction_proxy::switches::kEnableDataReductionProxyConfigClient);
+}
+
 void DataReductionProxyParams::EnableQuic(bool enable) {
   quic_enabled_ = enable;
   DCHECK(!quic_enabled_ || IsIncludedInQuicFieldTrial());
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
index 30c51ff..0f6aea8 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_params.h
@@ -113,6 +113,9 @@ class DataReductionProxyParams : public DataReductionProxyConfigValues {
 
   static std::string GetQuicFieldTrialName();
 
+  // Returns true if the Data Reduction Proxy config client should be used.
+  static bool IsConfigClientEnabled();
+
   // Constructs configuration parameters. If |kAllowed|, then the standard
   // data reduction proxy configuration is allowed to be used. If
   // |kfallbackAllowed| a fallback proxy can be used if the primary proxy is
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.cc b/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.cc
index bab8af0..2386931 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.cc
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.cc
@@ -70,5 +70,9 @@ const char kEnableDataReductionProxyBypassWarning[] =
 const char kClearDataReductionProxyDataSavings[] =
     "clear-data-reduction-proxy-data-savings";
 
+// Enable the data reduction proxy config client.
+const char kEnableDataReductionProxyConfigClient[] =
+    "enable-data-reduction-proxy-config-client";
+
 }  // namespace switches
 }  // namespace data_reduction_proxy
diff --git a/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.h b/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.h
index cd6d08d..1a8f7c0 100644
--- a/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.h
+++ b/components/data_reduction_proxy/core/common/data_reduction_proxy_switches.h
@@ -28,6 +28,7 @@ extern const char kEnableDataReductionProxyAlt[];
 extern const char kEnableDataReductionProxyLoFi[];
 extern const char kEnableDataReductionProxyBypassWarning[];
 extern const char kClearDataReductionProxyDataSavings[];
+extern const char kEnableDataReductionProxyConfigClient[];
 
 }  // namespace switches
 }  // namespace data_reduction_proxy