Ldap users cannot log in

FileVault 2 uses the GeneratedUID user attribute to save who is permitted to unlock an encrypted volume. If the GeneratedUID of a user differs from what was generated (or pulled from LDAP) when FileVault 2 was enabled, the user will not be permitted to unlock the machine, as their account will appear to be unavailable at the EFI menu. Also, this causes the crash of System Preferences on their Mac whenever they try to access the Security & Privacy prefpane.

This problem arises when /usr/bin/mcxrefresh runs and pulls a null value or a value different than what is stored locally from LDAP (if the attribute isn't defined for the user in question or is defined incorrectly, respectively), overwriting the GeneratedUID stored locally (which is generated and only stored locally when FileVault 2 is enabled without a matching LDAP attribute).

In other words, if an apple-generateduid value exists in LDAP for a user and is mapped properly on the users Mac to the GeneratedUID attribute, FileVault 2 will not generate a new value, but will instead use the value stored in LDAP.

I was able to resolve this issue by adding an attribute called apple-generateduid to the LDAP entry of any user experiencing this issue. I could generate a random value for this attribute in Python by running the following one-liner from my terminal:

python -c 'import uuid; print str(uuid.uuid4()).upper();'

This isn't the only step, however. You must also add a mapping for this attribute on the client side. This is easily done using the following steps:

1. Open System Preferences.
2. Click Users & Groups.
3. Click Login Options.
4. Click on the Unlock Icon.
5. Under Network Account Server, click Edit.
6. Click to highlight your directory server.
7. Under Services, double-click on your directory service (in my case, it was LDAPv3)
8. In the window that slides open, highlight your configuration name, and then click the Edit... button.
9. Under Search & Mappings scroll down and single-click on Users to highlight it.
10. Click the Add button (the left one).
11. Choose GeneratedUID from the list of available Attribute Types.
12. In the right column, click the Add button, and type apple-generateduid. Click OK to save the changes until you're back at the main System Preferences dialog.
13. At this point a mapping from GeneratedUID to apple-generateduid has been created. Now when OS X looks up the GeneratedUID value it will get the value of apple-generateduid from the user in questions LDAP entry.

Finally, it's important that the locally stored value of GeneratedUID and value stored on LDAP match. Run the following command and make sure the two GeneratedUID values match:

dscl /Search search /Users GeneratedUID $(dscl . read /Users/$(echo $USER) GeneratedUID | cut -d " " -f2)

It's possible that you need to set the Authentication Search Path inside of Directory Utility -> Search Policy -> Authentication...Make sure "Search" says "Custom Path", and that your Active Directory domain is listed below.

If you do not see your AD domain in the list, you can authenticate to Directory Utility by clicking the lock in the lower-left corner, and then add a new search path by clicking the "+" button below the list of paths. Your domain should show up under "Available Directory Domains".

This setting should allow users to authenticate against Active Directory when connecting to your server. However, if AD users can authenticate against your OS X server successfully, the Search Path is not likely to be the culprit.

Alternatively, Workgroup Manager still exists, and may allow you to investigate the AD node more explicitly.

Lastly, you may be required to enable cleartext authentication to be able to authenticate your AD users to your OS X Server hosted wiki (the article applies to Mountain Lion and lower systems, but may be the same procedure that is required for Mavericks).