Add additional status APIs for the TPM.

tpm.cc

 // Copyright (c) 2009-2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Contains the implementation of class Tpm
 
 #include "tpm.h"
 
 #include <base/file_util.h>
 #include <base/platform_thread.h>
@@ skipping 16 matching lines @@
 const char kTpmWellKnownPassword[] = TSS_WELL_KNOWN_SECRET;
 
 Tpm::Tpm()
     : context_handle_(0),
       default_crypto_(new Crypto()),
       crypto_(default_crypto_.get()),
       owner_password_(),
       password_sync_lock_(),
       is_disabled_(true),
       is_owned_(false),
-      is_srk_available_(false) {
+      is_srk_available_(false),
+      is_being_owned_(false) {
 }
 
 Tpm::~Tpm() {
   Disconnect();
 }
 
 bool Tpm::Init() {
   // Checking disabled and owned either via sysfs or via TSS calls will block if
   // ownership is being taken by another thread or process.  So for this to work
   // well, Tpm::Init() needs to be called before InitializeTpm() is called.  At
@@ skipping 460 matching lines @@
   if (is_disabled_) {
     return false;
   }
 
   SecureBlob default_owner_password(sizeof(kTpmWellKnownPassword));
   memcpy(default_owner_password.data(), kTpmWellKnownPassword,
          sizeof(kTpmWellKnownPassword));
 
   bool took_ownership = false;
   if (!is_owned_) {
+    is_being_owned_ = true;
     file_util::Delete(FilePath(kOpenCryptokiPath), true);
     file_util::Delete(FilePath(kTpmOwnedFile), false);
 
     if (!IsEndorsementKeyAvailable(context_handle_)) {
       if (!CreateEndorsementKey(context_handle_)) {
         LOG(ERROR) << "Failed to create endorsement key";
+        is_being_owned_ = false;
         return false;
       }
     }
 
     if (!IsEndorsementKeyAvailable(context_handle_)) {
       LOG(ERROR) << "Endorsement key is not available";
+      is_being_owned_ = false;
       return false;
     }
 
     if (!TakeOwnership(context_handle_, kMaxTimeoutRetries,
                        default_owner_password)) {
       LOG(ERROR) << "Take Ownership failed";
+      is_being_owned_ = false;
       return false;
     }
 
     is_owned_ = true;
     took_ownership = true;
   }
 
   // Ensure the SRK is available
   TSS_RESULT result;
   TSS_HKEY srk_handle;
   TSS_UUID SRK_UUID = TSS_UUID_SRK;
   if ((result = Tspi_Context_LoadKeyByUUID(context_handle_, TSS_PS_TYPE_SYSTEM,
                                            SRK_UUID, &srk_handle))) {
     is_srk_available_ = false;
   } else {
     Tspi_Context_CloseObject(context_handle_, srk_handle);
     is_srk_available_ = true;
   }
 
   // If we can open the TPM with the default password, then we still need to
   // zero the SRK password and unrestrict it, then change the owner password.
   TSS_HTPM tpm_handle;
   if (GetTpmWithAuth(context_handle_, default_owner_password, &tpm_handle) &&
       TestTpmAuth(tpm_handle)) {
     if (!ZeroSrkPassword(context_handle_, default_owner_password)) {
       LOG(ERROR) << "Couldn't zero SRK password";
+      is_being_owned_ = false;
       return false;
     }
 
     if (!UnrestrictSrk(context_handle_, default_owner_password)) {
       LOG(ERROR) << "Couldn't unrestrict the SRK";
+      is_being_owned_ = false;
       return false;
     }
     SecureBlob owner_password;
     CreateOwnerPassword(&owner_password);
 
     if (!ChangeOwnerPassword(context_handle_, default_owner_password,
                              owner_password)) {
       LOG(ERROR) << "Couldn't set the owner password";
+      is_being_owned_ = false;
       return false;
     }
 
     password_sync_lock_.Acquire();
     owner_password_.assign(owner_password.begin(), owner_password.end());
     password_sync_lock_.Release();
 
     file_util::WriteFile(FilePath(kTpmOwnedFile), NULL, 0);
   }
 
- return took_ownership;
+  is_being_owned_ = false;
+
+  return took_ownership;
 }
 
 bool Tpm::GetRandomData(size_t length, chromeos::Blob* data) {
   TSS_HCONTEXT context_handle;
   if (!OpenAndConnectTpm(&context_handle)) {
     LOG(ERROR) << "Could not open the TPM";
     return false;
   }
 
   TSS_HTPM tpm_handle;
@@ skipping 13 matching lines @@
   }
   memcpy(random.data(), tpm_data, random.size());
   Tspi_Context_FreeMemory(context_handle, tpm_data);
   chromeos::SecureMemset(tpm_data, 0, random.size());
   Tspi_Context_Close(context_handle);
   data->swap(random);
   return true;
 }
 
 } // namespace tpm_init