* Fixed: RFC 8040 yang-data extension allows non-key lists

* Added YANG_FLAG_NOKEY as exception to mandatory key lists

CHANGELOG.md

@@ -42,6 +42,8 @@ Developers may need to change their code
 
 ### Corrected Bugs
 
+* Fixed: RFC 8040 yang-data extension allows non-key lists
+  * Added YANG_FLAG_NOKEY as exception to mandatory key lists
 * Fixed: mandatory leaf in a uses statement caused abort
   * Occurence was in ietf-yang-patch.yang
 * Native RESTCONF fixes for http/1 or http/2 only modes

apps/restconf/restconf_lib.c

@@ -499,6 +499,14 @@ restconf_insert_attributes(cxobj *xdata,
  * @param[in] ys   Yang node of (unknown) statement belonging to extension
  * @retval     0   OK, all callbacks executed OK
  * @retval    -1   Error in one callback
+ * @note This extension adds semantics to YANG according to RFC8040 as follows:
+ *          - The list-stmt is not required to have a key-stmt defined.(NB!!)
+ *          - The if-feature-stmt is ignored if present.
+ *          - The config-stmt is ignored if present.
+ *          - The available identity values for any 'identityref'
+ *              leaf or leaf-list nodes are limited to the module
+ *              containing this extension statement and the modules
+ *              imported into that module.
  */
 int
 restconf_main_extension_cb(clicon_handle h,
@@ -522,6 +530,9 @@ restconf_main_extension_cb(clicon_handle h,
 	goto ok;
     if ((yn = ys_dup(yc)) == NULL)
 	goto done;
+    /* yang-data extension: The list-stmt is not required to have a key-stmt defined.
+     */
+    yang_flag_set(yn, YANG_FLAG_NOKEY);
     if (yn_insert(yang_parent_get(ys), yn) < 0)
 	goto done;
  ok:

lib/clixon/clixon_yang.h

@@ -53,8 +53,12 @@
  */
 #define YANG_FLAG_MARK  0x01  /* (Dynamic) marker for dynamic algorithms, eg expand and DAG */
 #define YANG_FLAG_TMP   0x02  /* (Dynamic) marker for dynamic algorithms, eg DAG detection */
+#define YANG_FLAG_NOKEY 0x04  /* Key not mandatory in this list, see eg yang-data extension in
+			       * RFC 8040 / ietf-restconf.yang
+			       * see restconf_main_extension_cb
+			       */
 #ifdef XML_EXPLICIT_INDEX
-#define YANG_FLAG_INDEX 0x04  /* This yang node under list is (extra) index. --> you can access
+#define YANG_FLAG_INDEX 0x08  /* This yang node under list is (extra) index. --> you can access
 			       * list elements using this index with binary search */
 #endif
 

lib/src/clixon_yang.c

@@ -259,11 +259,15 @@ yang_cv_get(yang_stmt *ys)
 /*! Set yang statement CLIgen variable
  * @param[in] ys  Yang statement node
  * @param[in] cv  cligen variable
+ * @note: Frees on replace, not if cv is NULL. This is for some ys_cp/ys_dup cases, which means 
+ *        you need to free it explicitly to set it to NULL proper.
  */
 int
 yang_cv_set(yang_stmt *ys,
 	    cg_var    *cv)
 {
+    if (cv != NULL && ys->ys_cv != NULL)
+	cv_free(ys->ys_cv);
     ys->ys_cv = cv;
     return 0;
 }
@@ -469,13 +473,14 @@ ys_free1(yang_stmt *ys,
 	 int        self)
 {
     cg_var *cv;
+
     if (ys->ys_argument){
 	free(ys->ys_argument);
 	ys->ys_argument = NULL;
     }
     if ((cv = yang_cv_get(ys)) != NULL){
+	yang_cv_set(ys, NULL); /* only frees on replace */
 	cv_free(cv);
-	yang_cv_set(ys, NULL);
     }
     if (ys->ys_cvec){
 	cvec_free(ys->ys_cvec);
@@ -629,6 +634,7 @@ ys_cp(yang_stmt *ynew,
 	    clicon_err(OE_YANG, errno, "strdup");
 	    goto done;
 	}
+    yang_cv_set(ynew, NULL);
     if ((cvo = yang_cv_get(yold)) != NULL){
 	if ((cvn = cv_dup(cvo)) == NULL){
 	    clicon_err(OE_YANG, errno, "cv_dup");
@@ -1469,7 +1475,8 @@ ys_real_module(yang_stmt  *ys,
  * @param[in] ys    Any yang statement in a yang tree
  * @retval    yspec The top yang specification
  * @see  ys_module
- * @see  yang_augment_node where shortcut is set
+ * @see  yang_augment_node where shortcut is set for augment
+ * @see  yang_myroot for first node under (sub)module
  */
 yang_stmt *
 ys_spec(yang_stmt *ys)

lib/src/clixon_yang_parse_lib.c

@@ -640,6 +640,9 @@ yang_expand_uses_node(yang_stmt *yn,
 	    if (yang_when_nsc_set(yg, wnsc) < 0) 
 		goto done;
 	}
+	/* This is for extensions that allow list keys to be optional, see restconf_main_extension_cb */
+	if (yang_flag_get(ys, YANG_FLAG_NOKEY))
+	    yang_flag_set(yg, YANG_FLAG_NOKEY);
 	yn->ys_stmt[i+k] = yg;
 	yg->ys_parent = yn;
 	k++;
@@ -1196,7 +1199,7 @@ ys_schemanode_check(yang_stmt *ys,
  * Verify the following rule:
  * RFC 7950 7.8.2: The "key" statement, which MUST be present if the list represents
  *                 configuration and MAY be present otherwise
- * Unless CLICON_YANG_LIST_CHECK is false
+ * Unless CLICON_YANG_LIST_CHECK is false (obsolete)
  * OR it is the "errors" rule of the ietf-restconf spec which seems to be a special case.
  */
 static int 
@@ -1222,20 +1225,14 @@ ys_list_check(clicon_handle h,
     if (keyw == Y_LIST &&
 	yang_find(ys, Y_KEY, NULL) == 0){
 	ymod = ys_module(ys);
-#if 1
+	/* Except nokey exceptions such as rrc 8040 yang-data */
-	/* Except restconf error extension from sanity check, dont know why it has no keys */
+	if (!yang_flag_get(yroot, YANG_FLAG_NOKEY)){
-	if (strcmp(yang_find_mynamespace(ys),"urn:ietf:params:xml:ns:yang:ietf-restconf")==0 &&
+	    /* Note obsolete */
-	    strcmp(yang_argument_get(ys),"error") == 0)
-	    ;
-	else
-#endif
-	    {
 	    if (clicon_option_bool(h, "CLICON_YANG_LIST_CHECK")){
 		clicon_log(LOG_ERR, "Error: LIST \"%s\" in module \"%s\" lacks key statement which MUST be present (See RFC 7950 Sec 7.8.2)", 
 			   yang_argument_get(ys),
 			   yang_argument_get(ymod)
 			   );
-
 		goto done;
 	    }
 	    else

test/mem.sh

@@ -40,7 +40,7 @@ function memonce(){
 	    sudo chmod 660 $valgrindfile
 	    sudo chown www-data $valgrindfile
 	    : ${DEMWAIT:=15} # valgrind backend needs some time to get up 
-	    clixon_restconf="/usr/bin/valgrind --leak-check=full --show-leak-kinds=all --suppressions=./valgrind-clixon.supp --track-fds=yes --trace-children=no  --child-silent-after-fork=yes --log-file=$valgrindfile clixon_restconf"
+	    clixon_restconf="/usr/bin/valgrind --num-callers=50 --leak-check=full --show-leak-kinds=all --suppressions=./valgrind-clixon.supp --track-fds=yes --trace-children=no  --child-silent-after-fork=yes --log-file=$valgrindfile clixon_restconf"
 
 	    ;;
 	*)