[SafeBrowsing] Block dangerous unchecked downloads based on a Finch trial.

chrome/browser/safe_browsing/unverified_download_field_trial_unittest.cc

+// 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 "chrome/browser/safe_browsing/unverified_download_field_trial.h"
+
+#include "base/command_line.h"
+#include "base/files/file_path.h"
+#include "base/metrics/field_trial.h"
+#include "chrome/common/chrome_switches.h"
+#include "chrome/common/safe_browsing/download_protection_util.h"
+#include "components/variations/variations_associated_data.h"
+#include "testing/gmock/include/gmock/gmock.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+namespace safe_browsing {
+
+namespace {
+
+const base::FilePath::CharType kSafeFilename[] = FILE_PATH_LITERAL("foo.txt");
+const base::FilePath::CharType kHandledFilename[] =
+    FILE_PATH_LITERAL("foo.exe");
+
+using FieldTrialParameters = std::map<std::string, std::string>;
+
+class ScopedFieldTrialState {
+ public:
+  ScopedFieldTrialState(const std::string& group_name,
+                        const FieldTrialParameters& parameters)
+      : field_trial_list_(nullptr) {
+    variations::testing::ClearAllVariationIDs();
+    variations::testing::ClearAllVariationParams();
+
+    if (!parameters.empty()) {
+      EXPECT_TRUE(variations::AssociateVariationParams(
+          kUnverifiedDownloadFieldTrialName, group_name, parameters));
+    }
+    EXPECT_TRUE(base::FieldTrialList::CreateFieldTrial(
+        kUnverifiedDownloadFieldTrialName, group_name));
+  }
+
+  explicit ScopedFieldTrialState(const std::string& group_name)
+      : ScopedFieldTrialState(group_name, FieldTrialParameters()) {}
+
+  ~ScopedFieldTrialState() {
+    variations::testing::ClearAllVariationIDs();
+    variations::testing::ClearAllVariationParams();
+  }
+
+ private:
+  base::FieldTrialList field_trial_list_;
+};
+
+}  // namespace
+
+// Verify some test assumptions. Namely, that kSafeFilename is not a supported
+// binary file and that kHandledFilename is.
+TEST(UnverifiedDownloadFieldTrialTest, Assumptions) {
+  EXPECT_TRUE(safe_browsing::download_protection_util::IsSupportedBinaryFile(
+      base::FilePath(kHandledFilename)));
+  EXPECT_FALSE(safe_browsing::download_protection_util::IsSupportedBinaryFile(
+      base::FilePath(kSafeFilename)));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, CommandLine_AllowAll) {
+  base::CommandLine::ForCurrentProcess()->AppendSwitch(
+      switches::kAllowUncheckedDangerousDownloads);
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, CommandLine_DisallowDangerous) {
+  base::CommandLine::ForCurrentProcess()->AppendSwitch(
+      switches::kDisallowUncheckedDangerousDownloads);
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, DisableAll) {
+  ScopedFieldTrialState field_trial(kUnverifiedDownloadFieldTrialDisableAll);
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, DisableByParam) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = ".abc,.def";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] = ".xyz";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableByParameter, parameters);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.xyz"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.abc"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.def"))));
+}
+
+// Verify that nothing terrible happens if no parameters are specified for a
+// group that expects parameters.
+TEST(UnverifiedDownloadFieldTrialTest, DisableByParam_NoParameters) {
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableByParameter);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+// Verify that nothing terrible happens if the parameters set for a field trial
+// are malformed.
+TEST(UnverifiedDownloadFieldTrialTest, DisableByParam_BadFormat) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = "abcasdfa#??# ~def";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] =
+      "Robert'); DROP TABLE FinchTrials;--";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableByParameter, parameters);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+// Verify that nothing terrible happens if the parameters set for a field trial
+// are empty.
+TEST(UnverifiedDownloadFieldTrialTest, DisableByParam_Empty) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = "";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] = "";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableByParameter, parameters);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, DisableByParam_CaseSensitive) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = ".ABC,.xyz";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] = "";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableByParameter, parameters);
+
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.abc"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("FOO.ABC"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("FOO.XYZ"))));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("FOO.txt"))));
+}
+
+TEST(UnverifiedDownloadFieldTrialTest, DisableSBTypesAndByParameter) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = ".abc,.def";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] = ".xyz";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableSBTypesAndByParameter, parameters);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.xyz"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.abc"))));
+  EXPECT_FALSE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(FILE_PATH_LITERAL("foo.def"))));
+}
+
+// Verify that a whitelist is able to override the SafeBrowsing file type list.
+TEST(UnverifiedDownloadFieldTrialTest,
+     DisableSBTypesAndByParameter_OverrideSB) {
+  FieldTrialParameters parameters;
+  parameters[kUnverifiedDownloadFieldTrialBlacklistParam] = ".abc,.def";
+  parameters[kUnverifiedDownloadFieldTrialWhitelistParam] = ".exe";
+  ScopedFieldTrialState field_trial(
+      kUnverifiedDownloadFieldTrialDisableSBTypesAndByParameter, parameters);
+
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kSafeFilename)));
+  EXPECT_TRUE(safe_browsing::IsUnverifiedDownloadAllowedByFieldTrial(
+      base::FilePath(kHandledFilename)));
+}
+
+}  // namespace safe_browsing