Implement Mac Keychain migration algorithm.

crypto/mock_apple_keychain.h

Index: crypto/mock_apple_keychain.h
diff --git a/crypto/mock_apple_keychain.h b/crypto/mock_apple_keychain.h
index 3948d489755a3049a268772763648fe5d3cf9994..37d4d061d22e632ec574a3f7ccfc593a73614cc4 100644
--- a/crypto/mock_apple_keychain.h
+++ b/crypto/mock_apple_keychain.h
@@ -118,6 +118,8 @@ class CRYPTO_EXPORT MockAppleKeychain : public AppleKeychain {
   };
   // Adds a keychain item with the given info to the test set.
   void AddTestItem(const KeychainTestData& item_data);
+
+  static void set_locked(bool locked) { locked_ = locked; }

[Ryan Sleevi, 2015/06/26 10:46:38]

I feel that, design wise, adding a static member variable here is somewhat
inconsistent / problematic from a design point. This is especially problematic
from a unit test perspective, because if you fail to reset this flag, the test
can have side-effects.

Could you explain/explore why using
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/pas...
wouldn't work, and making this an instance-member on the class - either part of
the base crypto::AppleKeychain interface (with noop in for the concrete impl) or
via casting for the test?

Just wanting to understand this design better, and what the challenges are to
doing it as an instance member, because this represents a bit of a red flag.

[vasilii, 2015/06/26 12:18:48]

You're absolutely right. The original idea was to make it static so
OSCrypt::EncryptString() also fails. However, the approach failed for the
reasons you mentioned.

 #endif  // !defined(OS_IOS)
 
   // |FindGenericPassword()| can return different results depending on user
@@ -201,6 +203,10 @@ class CRYPTO_EXPORT MockAppleKeychain : public AppleKeychain {
 
   static const SecKeychainSearchRef kDummySearchRef;
 
+  // Simulates the state when the user refuses to unclock the Keychain.
+  // If true, reading and modifying a password value result in errSecAuthFailed.
+  static bool locked_;
+
   typedef struct KeychainPasswordData {
     KeychainPasswordData() : data(NULL), length(0) {}
     void* data;