Only store leading 13 bits of password hash.

chrome/browser/signin/local_auth_unittest.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/signin/local_auth.h"
 
 #include "base/base64.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/profiles/profile_manager.h"
 #include "chrome/test/base/testing_browser_process.h"
 #include "chrome/test/base/testing_pref_service_syncable.h"
 #include "chrome/test/base/testing_profile.h"
 #include "chrome/test/base/testing_profile_manager.h"
 #include "components/os_crypt/os_crypt.h"
 
 #include "testing/gtest/include/gtest/gtest.h"
 
-using namespace chrome;
-
 TEST(LocalAuthTest, SetAndCheckCredentials) {
   TestingProfileManager testing_profile_manager(
       TestingBrowserProcess::GetGlobal());
   ASSERT_TRUE(testing_profile_manager.SetUp());
   Profile* prof = testing_profile_manager.CreateTestingProfile("p1");
   ProfileInfoCache& cache =
       testing_profile_manager.profile_manager()->GetProfileInfoCache();
   EXPECT_EQ(1U, cache.GetNumberOfProfiles());
   EXPECT_EQ("", cache.GetLocalAuthCredentialsOfProfileAtIndex(0));
 
 #if defined(OS_MACOSX)
   OSCrypt::UseMockKeychain(true);
 #endif
 
   std::string password("Some Password");
-  EXPECT_FALSE(ValidateLocalAuthCredentials(prof, password));
+  EXPECT_FALSE(LocalAuth::ValidateLocalAuthCredentials(prof, password));
 
-  SetLocalAuthCredentials(prof, password);
+  LocalAuth::SetLocalAuthCredentials(prof, password);
   std::string passhash = cache.GetLocalAuthCredentialsOfProfileAtIndex(0);
 
   // We perform basic validation on the written record to ensure bugs don't slip
   // in that cannot be seen from the API:
   //  - The encoding exists (we can guarantee future backward compatibility).
   //  - The plaintext version of the password is not mistakenly stored anywhere.
   EXPECT_FALSE(passhash.empty());
-  EXPECT_EQ('1', passhash[0]);
+  EXPECT_EQ('2', passhash[0]);
   EXPECT_EQ(passhash.find(password), std::string::npos);
 
   std::string decodedhash;
   base::Base64Decode(passhash.substr(1), &decodedhash);
   EXPECT_FALSE(decodedhash.empty());
   EXPECT_EQ(decodedhash.find(password), std::string::npos);
 
-  EXPECT_TRUE(ValidateLocalAuthCredentials(prof, password));
-  EXPECT_FALSE(ValidateLocalAuthCredentials(prof, password + "1"));
+  EXPECT_TRUE(LocalAuth::ValidateLocalAuthCredentials(prof, password));
+  EXPECT_FALSE(LocalAuth::ValidateLocalAuthCredentials(prof, password + "1"));
 
-  SetLocalAuthCredentials(prof, password);  // makes different salt
+  LocalAuth::SetLocalAuthCredentials(prof, password);  // makes different salt
   EXPECT_NE(passhash, cache.GetLocalAuthCredentialsOfProfileAtIndex(0));
 }
+
+
+TEST(LocalAuthTest, SetUpgradeAndCheckCredentials) {
+  TestingProfileManager testing_profile_manager(
+      TestingBrowserProcess::GetGlobal());
+  ASSERT_TRUE(testing_profile_manager.SetUp());
+  Profile* prof = testing_profile_manager.CreateTestingProfile("p1");
+  ProfileInfoCache& cache =
+      testing_profile_manager.profile_manager()->GetProfileInfoCache();
+
+  std::string password("Some Password");
+  size_t profile_index = cache.GetIndexOfProfileWithPath(prof->GetPath());
+  LocalAuth::SetLocalAuthCredentialsWithEncoding(profile_index, password, '1');
+
+  // Ensure we indeed persisted the correct encoding.
+  std::string oldpasshash = cache.GetLocalAuthCredentialsOfProfileAtIndex(
+      profile_index);
+  EXPECT_EQ('1', oldpasshash[0]);
+
+  // Validate, ensure we can validate against the old encoding.
+  EXPECT_TRUE(LocalAuth::ValidateLocalAuthCredentials(prof, password));
+
+  // Ensure we updated the encoding.
+  std::string newpasshash = cache.GetLocalAuthCredentialsOfProfileAtIndex(
+      profile_index);
+  EXPECT_EQ('2', newpasshash[0]);
+  // Encoding '2' writes fewer bytes than encoding '1'.
+  EXPECT_LE(newpasshash.length(), oldpasshash.length());
+
+  // Validate, ensure we validate against the new encoding.
+  EXPECT_TRUE(LocalAuth::ValidateLocalAuthCredentials(prof, password));
+}
+
+// Test truncation where each byte is left whole.
+TEST(LocalAuthTest, TruncateStringEvenly) {
+  std::string two_chars = "A6";
+  std::string three_chars = "A6C";
+  EXPECT_EQ(two_chars, LocalAuth::TruncateStringByBits(two_chars, 16));
+  EXPECT_EQ(two_chars, LocalAuth::TruncateStringByBits(three_chars, 16));
+
+  EXPECT_EQ(two_chars, LocalAuth::TruncateStringByBits(two_chars, 14));
+  EXPECT_EQ(two_chars, LocalAuth::TruncateStringByBits(three_chars, 14));
+}
+
+// Test truncation that affects the results within a byte.
+TEST(LocalAuthTest, TruncateStringUnevenly) {
+  std::string two_chars = "Az";
+  std::string three_chars = "AzC";
+  // 'z' = 0x7A, ':' = 0x3A.
+  std::string two_chars_truncated = "A:";
+  EXPECT_EQ(two_chars_truncated,
+      LocalAuth::TruncateStringByBits(two_chars, 14));
+  EXPECT_EQ(two_chars_truncated,
+      LocalAuth::TruncateStringByBits(three_chars, 14));
+}