security: Pair-up Tpm and Pib in KeyChain
In this commit, we also change the HOME setting for test cases.
Change-Id: I7fa15461555b3519d9d2005c6956c167ed07d66f
Refs: #2242
Refs: #2260
diff --git a/tests/unit-tests/security/config-file-readme.txt b/tests/unit-tests/security/config-file-readme.txt
new file mode 100644
index 0000000..44e5f61
--- /dev/null
+++ b/tests/unit-tests/security/config-file-readme.txt
@@ -0,0 +1,11 @@
+In test, we set a test-specific "HOME", which cause OS X keychain look for the
+default keychain of a "different" user. If the default keychain does not exist,
+all subsequent calls to OS X keychain will fail. User interaction (such as
+specifying password) is required to create a keychain. However, user interaction
+is not feasible in automated tests.
+
+This problem is caused by the OS X system assumption that one user must have a
+login keychain, which is also the user's default keychain, because a user
+account is always created with a login keychain as default. Thus OS X system
+infers a user according to the HOME env, and did not expect user to change the
+HOME env in normal use.