Heimdal's HDB plugin interface, and hence Samba's KDC that depends upon
it, doesn't work on 32-bit builds due to structure fields being arranged
in the wrong order. This problem presents itself in the form of
segmentation faults on 32-bit systems, but goes unnoticed on 64-bit
builds thanks to extra structure padding absorbing the errant fields.
This commit reorders the HDB plugin structure fields to prevent crashes
and introduces a common macro to ensure every plugin presents a
consistent interface.
Samba BUG: https://bugzilla.samba.org/show_bug.cgi?id=15110
Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Remove hdb_entry_ex and revert to the original design of hdb_entry (except with
an additional context member in hdb_entry which is managed by the free_entry
method in HDB).
Add some notes about the KDC plugin API contract, and require plugins to
explicitly indicate which version of the API they support (remove the macro
alias for the current version).
Rename the "windc" plugin API to the more general "kdc" plugin API, for two
reasons: the Heimdal KDC uses the Windows PAC even when not emulating a domain
controller, and the plugin API has accreted methods that are not specific to
emulating a domain controller (such as referral_policy and finalize_reply).
