Make crypto::GetSystemNSSKeySlot asynchronous.

crypto/nss_util.cc

 // Copyright (c) 2012 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 "crypto/nss_util.h"
 #include "crypto/nss_util_internal.h"
 
 #include <nss.h>
 #include <pk11pub.h>
 #include <plarena.h>
@@ skipping 576 matching lines @@
     if (!thread_checker_.CalledOnValidThread()) {
       DVLOG(1) << "Called on wrong thread.\n"
                << base::debug::StackTrace().ToString();
     }
 
     return PK11_GetInternalKeySlot();
   }
 #endif
 
 #if defined(OS_CHROMEOS)
-  PK11SlotInfo* GetSystemNSSKeySlot() {
+  void GetSystemNSSKeySlotCallback(
+      const base::Callback<void(ScopedPK11Slot)>& callback) {
+    callback.Run(ScopedPK11Slot(PK11_ReferenceSlot(tpm_slot_)));
+  }
+
+  ScopedPK11Slot GetSystemNSSKeySlot(
+      const base::Callback<void(ScopedPK11Slot)>& callback) {
     DCHECK(thread_checker_.CalledOnValidThread());
-
     // TODO(mattm): chromeos::TPMTokenloader always calls
     // InitializeTPMTokenAndSystemSlot with slot 0.  If the system slot is
     // disabled, tpm_slot_ will be the first user's slot instead. Can that be
     // detected and return NULL instead?
-    if (tpm_token_enabled_for_nss_ && IsTPMTokenReady(base::Closure()))
-      return PK11_ReferenceSlot(tpm_slot_);
-    // If we were supposed to get the hardware token, but were
-    // unable to, return NULL rather than fall back to sofware.
-    return NULL;
+
+    base::Closure wrapped_callback;
+    if (!callback.is_null()) {
+      wrapped_callback =
+          base::Bind(&NSSInitSingleton::GetSystemNSSKeySlotCallback,
+                     base::Unretained(this) /* singleton is leaky */,
+                     callback);
+    }
+    if (IsTPMTokenReady(wrapped_callback))
+      return ScopedPK11Slot(PK11_ReferenceSlot(tpm_slot_));
+    return ScopedPK11Slot();
   }
 #endif
 
 #if defined(USE_NSS)
   base::Lock* write_lock() {
     return &write_lock_;
   }
 #endif  // defined(USE_NSS)
 
   // This method is used to force NSS to be initialized without a DB.
@@ skipping 374 matching lines @@
       : lock_(SECMOD_GetDefaultModuleListLock()) {
     SECMOD_GetReadLock(lock_);
   }
 
 AutoSECMODListReadLock::~AutoSECMODListReadLock() {
   SECMOD_ReleaseReadLock(lock_);
 }
 #endif  // defined(USE_NSS)
 
 #if defined(OS_CHROMEOS)
-PK11SlotInfo* GetSystemNSSKeySlot() {
-  return g_nss_singleton.Get().GetSystemNSSKeySlot();
+ScopedPK11Slot GetSystemNSSKeySlot(
+    const base::Callback<void(ScopedPK11Slot)>& callback) {
+  return g_nss_singleton.Get().GetSystemNSSKeySlot(callback);
 }
 
 void SetSystemKeySlotForTesting(ScopedPK11Slot slot) {
   g_nss_singleton.Get().SetSystemKeySlotForTesting(ScopedPK11Slot());
 }
 
 void EnableTPMTokenForNSS() {
   g_nss_singleton.Get().EnableTPMTokenForNSS();
 }
 
@@ skipping 66 matching lines @@
   return time.ToInternalValue() - base::Time::UnixEpoch().ToInternalValue();
 }
 
 #if !defined(OS_CHROMEOS)
 PK11SlotInfo* GetPersistentNSSKeySlot() {
   return g_nss_singleton.Get().GetPersistentNSSKeySlot();
 }
 #endif
 
 }  // namespace crypto