This is important as Windows clients with KB5028166 seem to
call netr_LogonGetCapabilities with query_level=2 after
a call with query_level=1.
An unpatched Windows Server returns DCERPC_NCA_S_FAULT_INVALID_TAG
for query_level values other than 1.
While Samba tries to return NT_STATUS_NOT_SUPPORTED, but
later fails to marshall the response, which results
in DCERPC_FAULT_BAD_STUB_DATA instead.
Because we don't have any documentation for level 2 yet,
we just try to behave like an unpatched server and
generate DCERPC_NCA_S_FAULT_INVALID_TAG instead of
DCERPC_FAULT_BAD_STUB_DATA.
Which allows patched Windows clients to keep working
against a Samba DC.
BUG: https://bugzilla.samba.org/show_bug.cgi?id=15418
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>
Autobuild-User(master): Stefan Metzmacher <metze@samba.org>
Autobuild-Date(master): Mon Jul 17 07:35:09 UTC 2023 on atb-devel-224
(cherry picked from commit
dfeabce44fbb78083fbbb2aa634fc4172cf83db9)
+++ /dev/null
-^samba3.rpc.schannel.*\.schannel\(nt4_dc
struct netlogon_creds_CredentialState *creds;
NTSTATUS status;
+ switch (r->in.query_level) {
+ case 1:
+ break;
+ case 2:
+ /*
+ * Until we know the details behind KB5028166
+ * just return DCERPC_NCA_S_FAULT_INVALID_TAG
+ * like an unpatched Windows Server.
+ */
+ FALL_THROUGH;
+ default:
+ /*
+ * There would not be a way to marshall the
+ * the response. Which would mean our final
+ * ndr_push would fail an we would return
+ * an RPC-level fault with DCERPC_FAULT_BAD_STUB_DATA.
+ *
+ * But it's important to match a Windows server
+ * especially before KB5028166, see also our bug #15418
+ * Otherwise Windows client would stop talking to us.
+ */
+ p->fault_state = DCERPC_NCA_S_FAULT_INVALID_TAG;
+ return NT_STATUS_NOT_SUPPORTED;
+ }
+
become_root();
status = dcesrv_netr_creds_server_step_check(p->dce_call,
p->mem_ctx,
return status;
}
- if (r->in.query_level != 1) {
- return NT_STATUS_NOT_SUPPORTED;
- }
-
r->out.capabilities->server_capabilities = creds->negotiate_flags;
return NT_STATUS_OK;