s4-dsdb: Create KdfParameters at runtime

While this is by definition less efficient, I prefer not to have the magic
buffer of pre-caclulated bytes, we don't create Root Keys very often.

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Reviewed-by: Douglas Bagnall <douglas.bagnall@catalyst.net.nz>

diff --git a/source4/dsdb/gmsa/gkdi.c b/source4/dsdb/gmsa/gkdi.c
index 4a005754be3e449325c41d64e4f23e49a7c65931..3a79a5eb5fc8b4c9240cd3701e0747fe8c7002d1 100644 (file)
--- a/source4/dsdb/gmsa/gkdi.c
+++ b/source4/dsdb/gmsa/gkdi.c
@@ -31,6 +31,8 @@
 #include "dsdb/samdb/ldb_modules/util.h"
 #include "dsdb/samdb/samdb.h"
 #include "dsdb/common/proto.h"
+#include "librpc/gen_ndr/gkdi.h"
+#include "librpc/gen_ndr/ndr_gkdi.h"
 
 static int gkdi_create_root_key(TALLOC_CTX *mem_ctx,
                                struct ldb_context *const ldb,
@@ -53,6 +55,7 @@ static int gkdi_create_root_key(TALLOC_CTX *mem_ctx,
        uint64_t server_config_PublicKeyLength;
        uint64_t server_config_PrivateKeyLength;
        struct KdfAlgorithm kdf_algorithm;
+       DATA_BLOB kdf_parameters_blob = data_blob_null;
        struct ldb_message *add_msg = NULL;
        NTSTATUS status = NT_STATUS_OK;
        int ret = LDB_SUCCESS;
@@ -149,14 +152,26 @@ static int gkdi_create_root_key(TALLOC_CTX *mem_ctx,
                = ldb_msg_find_ldb_val(server_config_msg,
                                       "msKds-KDFParam");
        if (server_config_KDFParam == NULL) {
-               static const uint8_t kdf_parameters[] = {
-                       0,   0, 0,   0, 1,   0, 0,   0, 14,  0,
-                       0,   0, 0,   0, 0,   0, 'S', 0, 'H', 0,
-                       'A', 0, '5', 0, '1', 0, '2', 0, 0,   0,
+               struct KdfParameters kdf_parameters = {
+                       .hash_algorithm = "SHA512"
                };
-               static const DATA_BLOB kdf_parameters_blob = {
-                       discard_const_p(uint8_t, kdf_parameters),
-                       sizeof kdf_parameters};
+               enum ndr_err_code err;
+
+               err = ndr_push_struct_blob(&kdf_parameters_blob,
+                                          tmp_ctx,
+                                          &kdf_parameters,
+                                          (ndr_push_flags_fn_t)
+                                          ndr_push_KdfParameters);
+
+               if (!NDR_ERR_CODE_IS_SUCCESS(err)) {
+                       status = ndr_map_error2ntstatus(err);
+                       ldb_asprintf_errstring(ldb,
+                                              "KdfParameters pull failed: %s\n",
+                                              nt_errstr(status));
+                       ret = LDB_ERR_UNDEFINED_ATTRIBUTE_TYPE;
+                       goto out;
+               }
+
                server_config_KDFParam = &kdf_parameters_blob;
        }