Update keygen to use correct NSS slot on ChromeOS multiprofile.

crypto/nss_crypto_module_delegate.h

 // 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.
 
-#ifndef CRYPTO_CRYPTO_MODULE_BLOCKING_PASSWORD_DELEGATE_H_
-#define CRYPTO_CRYPTO_MODULE_BLOCKING_PASSWORD_DELEGATE_H_
+#ifndef CRYPTO_NSS_CRYPTO_MODULE_DELEGATE_H_
+#define CRYPTO_NSS_CRYPTO_MODULE_DELEGATE_H_
 
 #include <string>
 
+#include "base/callback_forward.h"
+#include "crypto/scoped_nss_types.h"
+
 namespace crypto {
 
 // PK11_SetPasswordFunc is a global setting.  An implementation of
-// CryptoModuleBlockingPasswordDelegate should be passed as the user data
-// argument (|wincx|) to relevant NSS functions, which the global password
-// handler will call to do the actual work.
+// CryptoModuleBlockingPasswordDelegate should be passed using wincx() as the
+// user data argument (|wincx|) to relevant NSS functions, which the global
+// password handler will call to do the actual work. This delegate should only
+// be used in NSS calls on worker threads due to the blocking nature.
 class CryptoModuleBlockingPasswordDelegate {
  public:
   virtual ~CryptoModuleBlockingPasswordDelegate() {}
 
-  // Requests a password to unlock |slot_name|. The interface is
-  // synchronous because NSS cannot issue an asynchronous
-  // request. |retry| is true if this is a request for the retry
-  // and we previously returned the wrong password.
+  // Return a value suitable for passing to the |wincx| argument of relevant NSS
+  // functions. This should be used instead of passing the object pointer
+  // directly to avoid accidentally casting a pointer to a subclass to void* and
+  // then casting back to a pointer of the base class
+  void* wincx() { return this; }
+
+  // Requests a password to unlock |slot_name|. The interface is synchronous
+  // because NSS cannot issue an asynchronous request. |retry| is true if this
+  // is a request for the retry and we previously returned the wrong password.
   // The implementation should set |*cancelled| to true if the user cancelled
   // instead of entering a password, otherwise it should return the password the
   // user entered.
   virtual std::string RequestPassword(const std::string& slot_name, bool retry,
                                       bool* cancelled) = 0;
+
+};
+
+// Extends CryptoModuleBlockingPasswordDelegate with the ability to return a
+// slot in which to act. (Eg, which slot to store a generated key in.)
+class NSSCryptoModuleDelegate : public CryptoModuleBlockingPasswordDelegate {
+ public:
+  virtual ~NSSCryptoModuleDelegate() {}
+
+  // Get the slot to store the generated key.
+  virtual ScopedPK11Slot RequestSlot() = 0;
 };
 
 }  // namespace crypto
 
-#endif  // CRYPTO_CRYPTO_MODULE_BLOCKING_PASSWORD_DELEGATE_H_
+#endif  // CRYPTO_NSS_CRYPTO_MODULE_DELEGATE_H_