Refactored YANG min/max validation code, created new clixon_validate_…

…minmax.[ch]

Added new recursive minmax check for non-presence containers
This makes validation checks stricter, including check of incoming RPCs
Renamed xml_yang_check_list_unique_minmax() to xml_yang_minmax_recurse()
Fixed again: [YANG min-elements within non-presence container does not work](#355)

CHANGELOG.md

@@ -61,6 +61,16 @@ Expected: September 2022
     * idle-timeout for periodic call-homes.
   * An example util client is `clixon_restconf_callhome_client.c` used in test cases
 
+### API changes on existing protocol/config features
+
+Users may have to change how they access the system
+
+* Constraints on number of elements have been made stricter (ie unique, min/max-elements)
+  * Usecases that passed previously may now return error
+  * This includes:
+    * Check of incoming RPCs
+    * Check of non-presence containers
+
 ### Corrected Bugs
 
 * Fixed: [YANG ordering fails for nested choice and action](https://github.com/clicon/clixon/issues/356)

apps/backend/backend_client.c

@@ -393,7 +393,7 @@ from_client_edit_config(clicon_handle h,
     }
     /* Limited validation of incoming payload
      */
-    if ((ret = xml_yang_check_list_unique_minmax(xc, &xret)) < 0)
+    if ((ret = xml_yang_minmax_recurse(xc, &xret)) < 0)
 	goto done;
     /* xmldb_put (difflist handling) requires list keys */
     if (ret==1 && (ret = xml_yang_validate_list_key_only(xc, &xret)) < 0)

lib/clixon/clixon.h.in

@@ -96,6 +96,7 @@ extern "C" {
 #include <clixon/clixon_xml_map.h>
 #include <clixon/clixon_xml_bind.h>
 #include <clixon/clixon_xml_io.h>
+#include <clixon/clixon_validate_minmax.h>
 #include <clixon/clixon_validate.h>
 #include <clixon/clixon_datastore.h>
 #include <clixon/clixon_xpath_ctx.h>

lib/clixon/clixon_validate.h

@@ -34,7 +34,7 @@
   ***** END LICENSE BLOCK *****
 
  *
- * XML code
+ * Check YANG validation
  */
 
 #ifndef _CLIXON_VALIDATE_H_
@@ -45,7 +45,6 @@
  */
 int xml_yang_validate_rpc(clicon_handle h, cxobj *xrpc, cxobj **xret);
 int xml_yang_validate_rpc_reply(clicon_handle h, cxobj *xrpc, cxobj **xret);
-int xml_yang_check_list_unique_minmax(cxobj *xt, cxobj **xret);
 int xml_yang_validate_add(clicon_handle h, cxobj *xt, cxobj **xret);
 int xml_yang_validate_list_key_only(cxobj *xt, cxobj **xret);
 int xml_yang_validate_all(clicon_handle h, cxobj *xt, cxobj **xret);

lib/clixon/clixon_validate_minmax.h

@@ -0,0 +1,48 @@
+/*
+ *
+  ***** BEGIN LICENSE BLOCK *****
+ 
+  Copyright (C) 2009-2016 Olof Hagsand and Benny Holmgren
+  Copyright (C) 2017-2019 Olof Hagsand
+  Copyright (C) 2020-2022 Olof Hagsand and Rubicon Communications, LLC (Netgate)
+
+  This file is part of CLIXON.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+
+  Alternatively, the contents of this file may be used under the terms of
+  the GNU General Public License Version 3 or later (the "GPL"),
+  in which case the provisions of the GPL are applicable instead
+  of those above. If you wish to allow use of your version of this file only
+  under the terms of the GPL, and not to allow others to
+  use your version of this file under the terms of Apache License version 2, 
+  indicate your decision by deleting the provisions above and replace them with
+  the  notice and other provisions required by the GPL. If you do not delete
+  the provisions above, a recipient may use your version of this file under
+  the terms of any one of the Apache License version 2 or the GPL.
+
+  ***** END LICENSE BLOCK *****
+
+ *
+ * Check YANG validation for min/max-elements and unique
+ */
+
+#ifndef _CLIXON_VALIDATE_MINMAX_H_
+#define _CLIXON_VALIDATE_MINMAX_H_
+
+/*
+ * Prototypes
+ */
+int xml_yang_minmax_recurse(cxobj *xt, cxobj **xret);
+
+#endif  /* _CLIXON_VALIDATE_MINMAX_H_ */

lib/clixon/clixon_xml.h

@@ -218,7 +218,6 @@ cxobj    *xml_child_i_type(cxobj *xn, int i, enum cxobj_type type);
 cxobj    *xml_child_i_set(cxobj *xt, int i, cxobj *xc);
 int       xml_child_order(cxobj *xn, cxobj *xc);
 cxobj    *xml_child_each(cxobj *xparent, cxobj *xprev,  enum cxobj_type type);
-
 int       xml_child_insert_pos(cxobj *x, cxobj *xc, int i);
 int       xml_childvec_set(cxobj *x, int len);
 cxobj   **xml_childvec_get(cxobj *x);

lib/src/Makefile.in

@@ -85,7 +85,7 @@ SRC     = clixon_sig.c clixon_uid.c clixon_log.c clixon_err.c clixon_event.c \
 	  clixon_yang.c clixon_yang_type.c clixon_yang_module.c \
 	  clixon_yang_parse_lib.c clixon_yang_sub_parse.c \
           clixon_yang_cardinality.c clixon_xml_changelog.c clixon_xml_nsctx.c \
-	  clixon_path.c clixon_validate.c \
+	  clixon_path.c clixon_validate.c clixon_validate_minmax.c \
 	  clixon_hash.c clixon_options.c clixon_data.c clixon_plugin.c \
 	  clixon_proto.c clixon_proto_client.c \
 	  clixon_xpath.c clixon_xpath_ctx.c clixon_xpath_eval.c clixon_xpath_function.c \

lib/src/clixon_datastore_read.c

@@ -1165,7 +1165,10 @@ xmldb_get0_clear(clicon_handle    h,
     /* Remove global defaults and empty non-presence containers */
     if (xml_defaults_nopresence(x, 1) < 0)
 	goto done;
-    /* clear flags: mark and change */
+    /* Clear XML tree of defaults */
+    if (xml_tree_prune_flagged(x, XML_FLAG_TRANSIENT, 1) < 0)
+	goto done;
+    /* clear mark and change */
     xml_apply0(x, CX_ELMNT, (xml_applyfn_t*)xml_flag_reset,
 	       (void*)(XML_FLAG_MARK|XML_FLAG_ADD|XML_FLAG_CHANGE));
  ok: