Add device-level token entryption to CertLibrary.

chrome/browser/chromeos/cros/cert_library.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 CHROME_BROWSER_CHROMEOS_CROS_CERT_LIBRARY_H_
 #define CHROME_BROWSER_CHROMEOS_CROS_CERT_LIBRARY_H_
 
 #include <string>
 
 #include "base/string16.h"
@@ skipping 83 matching lines @@
 
   // Returns the current list of user certificates.
   virtual const CertList& GetUserCertificates() const = 0;
 
   // Returns the current list of server certificates.
   virtual const CertList& GetServerCertificates() const = 0;
 
   // Returns the current list of server CA certificates.
   virtual const CertList& GetCACertificates() const = 0;
 
-  // Encrypts |token| with supplemental user key.
+  // Encrypts |token| with the system salt key (stable for the lifetime
+  // of the device).  Useful to avoid storing plain text in place like
+  // Local State.
+  virtual std::string EncryptDeviceToken(const std::string& token) = 0;

[zel, 2013/03/14 20:22:12]

EncryptWithSystemSalt might be a better name here.

[David Roche, 2013/03/14 23:03:29]

Done.

+
+  // Decrypts |token| with the system salt key (stable for the lifetime
+  // of the device).
+  virtual std::string DecryptDeviceToken(
+      const std::string& encrypted_token_hex) = 0;
+
+  // Encrypts |token| with supplemental user key (unique for each user).
   virtual std::string EncryptToken(const std::string& token) = 0;

[zel, 2013/03/14 20:22:12]

can we rename these to (Encrypt|Decrypt)WithUserKey

[David Roche, 2013/03/14 23:03:29]

Done.

 
-  // Decrypts |token| with supplemental user key.
-  virtual std::string DecryptToken(const std::string& encrypted_token) = 0;
+  // Decrypts |token| with supplemental user key (unique for each user).
+  virtual std::string DecryptToken(const std::string& encrypted_token_hex) = 0;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_CROS_CERT_LIBRARY_H_