accounts: Implement page searches for LDAP

Since we have so many accounts, we can no longer retrieve them
in one single search operation without disabling all safety measures
that OpenLDAP provides.

Hence we perform all search now as paged search retrieving up to
512 results at a time.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>

diff --git a/src/backend/accounts.py b/src/backend/accounts.py
index ee7fca0870e4d3652c173e26f4a08ec19d1b9ae9..b1160ac2e76df782ee1a325185fd02f3a3c45ae6 100644 (file)
--- a/src/backend/accounts.py
+++ b/src/backend/accounts.py
@@ -220,16 +220,47 @@ class Accounts(Object):
 
                t = time.time()
 
-               results = self.ldap.search_ext_s(search_base or self.search_base,
-                       ldap.SCOPE_SUBTREE, query, attrlist=attrlist, sizelimit=limit)
+               # Ask for up to 512 results being returned at a time
+               page_control = ldap.controls.SimplePagedResultsControl(True, size=512, cookie="")
+
+               results = []
+               pages = 0
+
+               # Perform the search
+               while True:
+                       response = self.ldap.search_ext(search_base or self.search_base,
+                               ldap.SCOPE_SUBTREE, query, attrlist=attrlist, sizelimit=limit,
+                               serverctrls=[page_control],
+                       )
+
+                       # Fetch all results
+                       type, data, rmsgid, serverctrls = self.ldap.result3(response)
+
+                       # Append to local copy
+                       results += data
+                       pages += 1
+
+                       controls = [c for c in serverctrls
+                               if c.controlType == ldap.controls.SimplePagedResultsControl.controlType]
+
+                       if not controls:
+                               logging.warning("The server ignores RFC 2696 control")
+                               break
+
+                       # Set the cookie for more results
+                       page_control.cookie = controls[0].cookie
+
+                       # There are no more results
+                       if not page_control.cookie:
+                               break
 
                # Log time it took to perform the query
-               logging.debug("Query took %.2fms" % ((time.time() - t) * 1000.0))
+               logging.debug("Query took %.2fms (%s page(s))" % ((time.time() - t) * 1000.0, pages))
 
                return results
 
        def _count(self, query):
-               res = self._query(query, attrlist=["dn"], limit=INT_MAX)
+               res = self._query(query, attrlist=["dn"])
 
                return len(res)