| Commit message (Collapse) | Author | Age | Files | Lines |
|---|
| |
|
|
|
| |
Initializing map cache may take time. Skip slapi-nis lookups untli
the map cache is ready.
|
| |
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
|
| |
When slapi-nis plugin responds on a search query, it holds read lock for
the internal structure called 'map cache'. The map cache lock can also be taken
for write when modification would be required like responding to DELETE, ADD, or
MODIFY operations.
As result of the lock semantics, write lock owner is blocked until all read lock
owners release their locks. This is generally not a problem but when readers sent
out LDAP query results, they call into SLAPI function that might take long time
to send out the data due to external reasons (network latencies, clients being
blocked, etc) and all this time map cache is locked for write operations.
When Kerberos KDC issues a TGT, it needs to modify few Kerberos-related attributes
in the principal's LDAP entry. These updates are generating MOD operations visible
by slapi-nis plugin which triggers re-scan of map cache to potentially replace
the affected entries. To perform potential replacement, slapi-nis has to take a write
lock and be blocked by outstanding readers.
Therefore, it is possible to encounter a situation where an LDAP client uses
SASL GSSAPI authentication and existing Kerberos ticket did expire in a course
of outstanding search request. According to LDAPv3 protocol specification, an
LDAP client must perform re-negotiation before reading any outstanding PDUs. It
would ask Kerberos KDC for a new (or renewed) TGT, that would cause MOD updates
for the primary tree which is tracked for changes by slapi-nis. These changes
would be blocked by a slapi-nis reader as the client cannot finish reading
outstanding PDUs yet.
To solve this problem, we avoid sending LDAP entries while keeping map cache
lock. Instead, we generate a linked list of copies of entries which will be
sent out. To allow sharing of entries between multiple parallel queries, we
hash the entry and reference the cached entry in the linked list with increased
reference count. Once entry is actually sent, its reference count decreased and
on reaching zero it is removed from the hash.
The entry in the hash table might become outdated. This is detected by comparing
both modifyTimestamp and entryUSN values of the entry to be sent and entry in the
hash table. If new version of the entry is different, hash table's entry reference
is replaced with a new copy. The old entry is not removed because it is still
referenced by some outstanding query processing. Thus, the hash table always
references the most recent version of an entry but there might be multiple copies
in possesion of the linked lists from the separate parallel queries.
An entry sharing via hash table can be disabled by setting
slapi-entry-cache: 0
in the definition, cn=Schema Compatibility,cn=plugins,cn=config
Resolves: rhbz#1273587
https://bugzilla.redhat.com/show_bug.cgi?id=1273587
|
| |
|
|
|
|
|
|
|
|
|
|
| |
users via NSS
When Schema Compatibility plugin is configured to enumerate users and groups
from Active Directory domains trusted by FreeIPA, use nss_sss module directly
instead of following nsswitch.conf configuration.
The issue with nsswitch.conf configuration is in the fact that for each request
all modules in NSS chain are processed while only one of them is responsible
for users from trusted Active Directory domains, namely, nss_sss.
|
| |
|
|
|
|
|
|
| |
PAM stack requires exclusive access, therefore we need to use a write
lock.
Required for authenticating synthetically created records coming outside
of LDAP store.
|
| |
|
|
|
| |
- add missing newlines at the end of a couple of messages
- make that one bit that we compare to zero unsigned instead of signed
|
| |
|
|
|
|
|
|
|
| |
* Check for BETXN support at build-time, provide options for disabling
or requiring that it be available for build to succeed.
* Track whether or not BETXN support is enabled in the plugin-local
state.
* Skip processing in post/internalpost callbacks if BETXN support is enabled.
* Skip work in betxnpost callbacks if BETXN support is disabled.
|
| | |
|
| | |
|
| | |
|
| | |
|
| |
|
|
| |
- make the tcp sizes tunable
|
| | |
|
| | |
|
| |
|
|
|
| |
- license text in source files
- elaborate on what's still to be done
|
| |
|
|
| |
- remove some more NSPRisms in cases when XDRisms are even more portable
|
| |
|
|
|
| |
- switch to using the plugin's entry for locating maps in preference to the
hard-coded location
|
| | |
|
| |
|
