Call crypto::InitializeTPMToken on the IO thread

chromeos/network/cert_loader.cc

 // Copyright (c) 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 "chromeos/network/cert_loader.h"
 
 #include <algorithm>
 
 #include "base/chromeos/chromeos_version.h"
+#include "base/message_loop/message_loop_proxy.h"
 #include "base/observer_list.h"
+#include "base/sequenced_task_runner.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/task_runner_util.h"
 #include "base/threading/worker_pool.h"
 #include "chromeos/dbus/cryptohome_client.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "crypto/encryptor.h"
 #include "crypto/nss_util.h"
 #include "crypto/sha2.h"
 #include "crypto/symmetric_key.h"
 #include "net/cert/nss_cert_database.h"
@@ skipping 30 matching lines @@
 CertLoader::CertLoader()
     : certificates_requested_(false),
       certificates_loaded_(false),
       certificates_update_required_(false),
       certificates_update_running_(false),
       tpm_token_state_(TPM_STATE_UNKNOWN),
       tpm_request_delay_(
           base::TimeDelta::FromMilliseconds(kInitialRequestDelayMs)),
       initialize_token_factory_(this),
       update_certificates_factory_(this) {
+}
+
+void CertLoader::Init(
+    const scoped_refptr<base::SequencedTaskRunner>& crypto_task_runner) {
+  main_task_runner_ = base::MessageLoopProxy::current();
+  crypto_task_runner_ = crypto_task_runner;
   net::CertDatabase::GetInstance()->AddObserver(this);
   if (LoginState::IsInitialized())
     LoginState::Get()->AddObserver(this);
   RequestCertificates();
 }
 
 CertLoader::~CertLoader() {
   net::CertDatabase::GetInstance()->RemoveObserver(this);
   if (LoginState::IsInitialized())
     LoginState::Get()->RemoveObserver(this);
@@ skipping 18 matching lines @@
 void CertLoader::RequestCertificates() {
   CHECK(thread_checker_.CalledOnValidThread());
   const bool logged_in = LoginState::IsInitialized() ?
       LoginState::Get()->IsUserLoggedIn() : false;
   VLOG(1) << "RequestCertificates: " << logged_in;
   if (certificates_requested_ || !logged_in)
     return;
 
   certificates_requested_ = true;
 
+  crypto_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&CertLoader::CallOpenPersistentNSSDB,
+                 initialize_token_factory_.GetWeakPtr()));
+}
+
+void CertLoader::CallOpenPersistentNSSDB() {
+  VLOG(1) << "CallOpenPersistentNSSDB";

[Ryan Sleevi, 2013/06/06 23:03:41]

Necessary?

[stevenjb, 2013/06/07 02:37:47]

This can be very helpful when debugging hardware that is failing for some
reason.

+
   // Ensure we've opened the user's key/certificate database.
   crypto::OpenPersistentNSSDB();
   if (base::chromeos::IsRunningOnChromeOS())
     crypto::EnableTPMTokenForNSS();
 
-  // This is the entry point to the TPM token initialization process, which we
-  // should do at most once.
-  DCHECK(!initialize_token_factory_.HasWeakPtrs());
-  InitializeTokenAndLoadCertificates();
+  // This is the entry point to the TPM token initialization process,
+  // which we should do at most once.
+  DCHECK(tpm_token_state_ == TPM_STATE_UNKNOWN);

[Ryan Sleevi, 2013/06/06 23:03:41]

DCHECK_EQ

[stevenjb, 2013/06/07 02:37:47]

Done.

+  main_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&CertLoader::InitializeTokenAndLoadCertificates,
+                 initialize_token_factory_.GetWeakPtr()));
 }
 
 void CertLoader::InitializeTokenAndLoadCertificates() {
   CHECK(thread_checker_.CalledOnValidThread());
   VLOG(1) << "InitializeTokenAndLoadCertificates";
 
   switch (tpm_token_state_) {
     case TPM_STATE_UNKNOWN: {
       DBusThreadManager::Get()->GetCryptohomeClient()->TpmIsEnabled(
       base::Bind(&CertLoader::OnTpmIsEnabled,
@@ skipping 13 matching lines @@
     }
     case TPM_TOKEN_READY: {
       // Retrieve token_name_ and user_pin_ here since they will never change
       // and CryptohomeClient calls are not thread safe.
       DBusThreadManager::Get()->GetCryptohomeClient()->Pkcs11GetTpmTokenInfo(
           base::Bind(&CertLoader::OnPkcs11GetTpmTokenInfo,
                      initialize_token_factory_.GetWeakPtr()));
       return;
     }
     case TPM_TOKEN_INFO_RECEIVED: {
+      if (base::chromeos::IsRunningOnChromeOS()) {
+        crypto_task_runner_->PostTask(
+            FROM_HERE,
+            base::Bind(&CertLoader::CallInitializeTPMToken,
+                       initialize_token_factory_.GetWeakPtr()));
+        return;
+      }
+      tpm_token_state_ = TPM_TOKEN_INITIALIZED;
+      // FALLTHROUGH_INTENDED
+    }
+    case TPM_TOKEN_INITIALIZED: {
       InitializeNSSForTPMToken();
       return;
     }
     case TPM_TOKEN_NSS_INITIALIZED: {
       StartLoadCertificates();
       return;
     }
   }
 }
 
@@ skipping 76 matching lines @@
   // TODO(stevenjb): The network code expects a slot ID, not a label. See
   // crbug.com/201101. For now, use a hard coded, well known slot instead.
   const char kHardcodedTpmSlot[] = "0";
   tpm_token_slot_ = kHardcodedTpmSlot;
   tpm_user_pin_ = user_pin;
   tpm_token_state_ = TPM_TOKEN_INFO_RECEIVED;
 
   InitializeTokenAndLoadCertificates();
 }
 
+void CertLoader::CallInitializeTPMToken() {
+  if (crypto::InitializeTPMToken(tpm_token_name_, tpm_user_pin_))
+    tpm_token_state_ = TPM_TOKEN_INITIALIZED;

[Ryan Sleevi, 2013/06/06 23:03:41]

THREADING: You're mutating this object on another thread. Is that really safe?

[stevenjb, 2013/06/07 02:37:47]

Was that rhetorical? :) Fixed with the change suggested below.

+  // Call InitializeNSSForTPMToken() on the main (UI) thread.
+  main_task_runner_->PostTask(
+      FROM_HERE,
+      base::Bind(&CertLoader::CallInitializeTPMToken,
+                 initialize_token_factory_.GetWeakPtr()));

[Ryan Sleevi, 2013/06/06 23:03:41]

THREADING: You're passing the same WeakPtr() on two different threads. This is a
violation of the WeakPtr contract, which states that a WeakPtr may only be
dereferenced on one thread.

Design suggestion:
Use PostTaskAndReplyWithResult to marshal the threading

if (!PostTaskAndReplyWithResult(
        crypto_task_runner_.get(),
        FROM_HERE,
        base::Bind(&crypto::InitializeTPMToken, tpm_token_name_, tpm_user_pin_),
        base::Bind(&CertLoader::CallInitializeTPMToken,
initialize_token_factory_.GetWeakPtr())) {
  // failed to initialize (no tasks posted)
}

CertLoader::CallInitializeTPMToken(bool initialized) {
  // handle yo stuff
}

this also frees you from tracking main_task_runner_ (PostTaskAndReplyWithResult
implicitly handles this)

[stevenjb, 2013/06/07 02:37:47]

Yeah, that was an oversight. I like your suggestion.
Done.

+}
+
 void CertLoader::InitializeNSSForTPMToken() {
   VLOG(1) << "InitializeNSSForTPMToken";
-
-  if (base::chromeos::IsRunningOnChromeOS() &&
-      !crypto::InitializeTPMToken(tpm_token_name_, tpm_user_pin_)) {
+  if (tpm_token_state_ != TPM_TOKEN_INITIALIZED) {
     RetryTokenInitializationLater();
     return;
   }
 
   tpm_token_state_ = TPM_TOKEN_NSS_INITIALIZED;
   InitializeTokenAndLoadCertificates();
 }
 
 void CertLoader::StartLoadCertificates() {
   VLOG(1) << "StartLoadCertificates";
@@ skipping 48 matching lines @@
   VLOG(1) << "OnCertRemoved";
   StartLoadCertificates();
 }
 
 void CertLoader::LoggedInStateChanged(LoginState::LoggedInState state) {
   VLOG(1) << "LoggedInStateChanged: " << state;
   RequestCertificates();
 }
 
 }  // namespace chromeos