[cros] Clear TPM password after EULA has been accepted.

BUG=chromium-os:7298
TEST=Manual. TPM ownership asquired, EULA hasn't been accepted, TPM password is always there. After EULA was accepted password is empty.

Review URL: http://codereview.chromium.org/4721002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@65787 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 15 insertions, 8 deletions

diff --git a/chrome/browser/chromeos/login/eula_view.cc b/chrome/browser/chromeos/login/eula_view.cc
index 42bad5f..a464795 100644
--- a/chrome/browser/chromeos/login/eula_view.cc
+++ b/chrome/browser/chromeos/login/eula_view.cc
@@ -196,18 +196,19 @@ void TpmInfoView::PullPassword() {
   chromeos::CryptohomeLibrary* cryptohome =
       chromeos::CrosLibrary::Get()->GetCryptohomeLibrary();
 
-  bool password_was_cleared = false;
+  bool password_acquired = false;
   if (password_->empty() && cryptohome->TpmIsReady()) {
-    bool password_acquired = cryptohome->TpmGetPassword(password_);
-    if (password_acquired) {
-      cryptohome->TpmClearStoredPassword();
-      if (password_->empty())
-        password_was_cleared = true;
-    } else {
+    password_acquired = cryptohome->TpmGetPassword(password_);
+    if (!password_acquired) {
       password_->clear();
+    } else if (password_->empty()) {
+      // For a fresh OOBE flow TPM is uninitialized,
+      // ownership process is started at the EULA screen,
+      // password is cleared after EULA is accepted.
+      LOG(ERROR) << "TPM returned an empty password.";
     }
   }
-  if (password_->empty() && !password_was_cleared) {
+  if (password_->empty() && !password_acquired) {
     // Password hasn't been acquired, reschedule pulling.
     MessageLoop::current()->PostDelayedTask(
         FROM_HERE,
diff --git a/chrome/browser/chromeos/login/wizard_controller.cc b/chrome/browser/chromeos/login/wizard_controller.cc
index 1962a29..54f12c2 100644
--- a/chrome/browser/chromeos/login/wizard_controller.cc
+++ b/chrome/browser/chromeos/login/wizard_controller.cc
@@ -17,6 +17,7 @@
 #include "base/logging.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/chromeos/cros/cros_library.h"
+#include "chrome/browser/chromeos/cros/cryptohome_library.h"
 #include "chrome/browser/chromeos/cros/input_method_library.h"
 #include "chrome/browser/chromeos/cros/login_library.h"
 #include "chrome/browser/chromeos/cros/system_library.h"
@@ -578,6 +579,11 @@ void WizardController::OnUpdateCompleted() {
 
 void WizardController::OnEulaAccepted() {
   MarkEulaAccepted();
+  if (chromeos::CrosLibrary::Get()->EnsureLoaded()) {
+    // TPM password could be seen on EULA screen, now it's safe to clear it.
+    chromeos::CrosLibrary::Get()->
+        GetCryptohomeLibrary()->TpmClearStoredPassword();
+  }
   InitiateOOBEUpdate();
 }