s4-dsdb: cope with failed searches in the linked attributes callback

This fixes a bug where we try to add an empty backlink because the
search for the forward link failed.

Autobuild-User: Andrew Tridgell <tridge@samba.org>
Autobuild-Date: Thu Mar 31 13:37:36 CEST 2011 on sn-devel-104

diff --git a/source4/dsdb/samdb/ldb_modules/linked_attributes.c b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
index 393f00fdb651dd352defe2ccb3c94c1aee10995c..69488001d95195f2376e67a9b257981ef76fc911 100644 (file)
--- a/source4/dsdb/samdb/ldb_modules/linked_attributes.c
+++ b/source4/dsdb/samdb/ldb_modules/linked_attributes.c
@@ -45,7 +45,6 @@ struct la_op_store {
        enum la_op {LA_OP_ADD, LA_OP_DEL} op;
        struct GUID guid;
        char *name;
-       char *value;
 };
 
 struct replace_context {
@@ -59,8 +58,7 @@ struct la_context {
        const struct dsdb_schema *schema;
        struct ldb_module *module;
        struct ldb_request *req;
-       struct ldb_dn *add_dn;
-       struct ldb_dn *del_dn;
+       struct ldb_dn *mod_dn;
        struct replace_context *rc;
        struct la_op_store *ops;
        struct ldb_extended *op_response;
@@ -319,7 +317,7 @@ static int la_mod_search_callback(struct ldb_request *req, struct ldb_reply *are
                                                LDB_ERR_OPERATIONS_ERROR);
                }
 
-               ac->add_dn = ac->del_dn = talloc_steal(ac, ares->message->dn);
+               ac->mod_dn = talloc_steal(ac, ares->message->dn);
 
                /* We don't populate 'rc' for ADD - it can't be deleting elements anyway */
                for (i = 0; rc && i < rc->num_elements; i++) {
@@ -572,9 +570,9 @@ static int linked_attributes_modify(struct ldb_module *module, struct ldb_reques
 
                /* We need to figure out our own extended DN, to fill in as the backlink target */
                if (ret == LDB_SUCCESS) {
-                       ret = ldb_request_add_control(search_req,
-                                                     LDB_CONTROL_EXTENDED_DN_OID,
-                                                     false, NULL);
+                       ret = dsdb_request_add_controls(search_req,
+                                                       DSDB_SEARCH_SHOW_DELETED |
+                                                       DSDB_SEARCH_SHOW_EXTENDED_DN);
                }
                if (ret == LDB_SUCCESS) {
                        talloc_steal(search_req, attrs);
@@ -867,9 +865,9 @@ static int la_add_callback(struct ldb_request *req, struct ldb_reply *ares)
                LDB_REQ_SET_LOCATION(search_req);
 
                if (ret == LDB_SUCCESS) {
-                       ret = ldb_request_add_control(search_req,
-                                                     LDB_CONTROL_EXTENDED_DN_OID,
-                                                     false, NULL);
+                       ret = dsdb_request_add_controls(search_req,
+                                                       DSDB_SEARCH_SHOW_DELETED |
+                                                       DSDB_SEARCH_SHOW_EXTENDED_DN);
                }
                if (ret != LDB_SUCCESS) {
                        return ldb_module_done(ac->req, NULL, NULL,
@@ -941,6 +939,11 @@ static int la_do_op_request(struct ldb_module *module, struct la_context *ac, st
        struct ldb_context *ldb;
        int ret;
 
+       if (ac->mod_dn == NULL) {
+               /* we didn't find the DN that we searched for */
+               return LDB_SUCCESS;
+       }
+
        ldb = ldb_module_get_ctx(ac->module);
 
        /* Create the modify request */
@@ -969,11 +972,7 @@ static int la_do_op_request(struct ldb_module *module, struct la_context *ac, st
                return ldb_oom(ldb);
        }
        ret_el->num_values = 1;
-       if (op->op == LA_OP_ADD) {
-               ret_el->values[0] = data_blob_string_const(ldb_dn_get_extended_linearized(new_msg, ac->add_dn, 1));
-       } else {
-               ret_el->values[0] = data_blob_string_const(ldb_dn_get_extended_linearized(new_msg, ac->del_dn, 1));
-       }
+       ret_el->values[0] = data_blob_string_const(ldb_dn_get_extended_linearized(new_msg, ac->mod_dn, 1));
 
        /* a backlink should never be single valued. Unfortunately the
           exchange schema has a attribute
@@ -996,7 +995,7 @@ static int la_do_op_request(struct ldb_module *module, struct la_context *ac, st
 
        ret = dsdb_module_modify(module, new_msg, DSDB_FLAG_NEXT_MODULE, ac->req);
        if (ret != LDB_SUCCESS) {
-               ldb_debug(ldb, LDB_DEBUG_WARNING, "Failed to apply linked attribute change '%s'\n%s\n",
+               ldb_debug(ldb, LDB_DEBUG_WARNING, __location__ ": failed to apply linked attribute change '%s'\n%s\n",
                          ldb_errstring(ldb),
                          ldb_ldif_message_string(ldb, op, LDB_CHANGETYPE_MODIFY, new_msg));
        }