- MMS server: more restrictive value type check when handling write access

src/mms/inc/mms_type_spec.h

@@ -91,6 +91,17 @@ MmsVariableSpecification_getNamedVariableRecursive(MmsVariableSpecification* sel
 MmsType
 MmsVariableSpecification_getType(MmsVariableSpecification* self);
 
+/**
+ * \brief Check if the value has exactly the same type as this variable specfication
+ *
+ * \param self the MmsVariableSpecification instance
+ * \param value the value to check
+ *
+ * \return true if type is matching, false otherwise
+ */
+bool
+MmsVariableSpecification_isValueOfType(MmsVariableSpecification* self, MmsValue* value);
+
 /**
  * \brief get the name of the variable
  *

src/mms/iso_mms/common/mms_type_spec.c

@@ -95,6 +95,64 @@ MmsVariableSpecification_getType(MmsVariableSpecification* self)
     return self->type;
 }
 
+bool
+MmsVariableSpecification_isValueOfType(MmsVariableSpecification* self, MmsValue* value)
+{
+    if ((self->type) == (value->type)) {
+
+        if ((self->type == MMS_STRUCTURE) || (self->type == MMS_ARRAY)) {
+
+            int componentCount = self->typeSpec.structure.elementCount;
+
+            if (componentCount != (int) MmsValue_getArraySize(value))
+                    return false;
+
+            if (self->type == MMS_STRUCTURE) {
+
+                int i;
+                for (i = 0; i < componentCount; i++) {
+
+                    if (MmsVariableSpecification_isValueOfType(self->typeSpec.structure.elements[i], MmsValue_getElement(value, i)) == false)
+                        return false;
+                }
+
+                return true;
+            }
+            else {
+                int i;
+                for (i = 0; i < componentCount; i++) {
+
+                    if (MmsVariableSpecification_isValueOfType(self->typeSpec.array.elementTypeSpec, MmsValue_getElement(value, i)) == false)
+                        return false;
+                }
+            }
+        }
+        else if (self->type == MMS_BIT_STRING) {
+            if (self->typeSpec.bitString == value->value.bitString.size)
+                return true;
+
+            if (self->typeSpec.bitString < 0) {
+                if (value->value.bitString.size <= (-self->typeSpec.bitString))
+                    return true;
+            }
+        }
+        else if (self->type == MMS_FLOAT) {
+            if ((self->typeSpec.floatingpoint.exponentWidth == value->value.floatingPoint.exponentWidth) &&
+                    (self->typeSpec.floatingpoint.formatWidth == value->value.floatingPoint.formatWidth))
+                return true;
+        }
+        else if (self->type == MMS_BINARY_TIME) {
+            if (self->typeSpec.binaryTime == value->value.binaryTime.size)
+                return true;
+        }
+        else
+            return true;
+
+    }
+
+    return false;
+}
+
 const char*
 MmsVariableSpecification_getName(MmsVariableSpecification* self)
 {

src/mms/iso_mms/server/mms_write_service.c

@@ -657,7 +657,7 @@ mmsServer_handleWriteRequest(
             }
 
             /* Check for correct type */
-            if (MmsValue_getType(value) != MmsVariableSpecification_getType(variable)) {
+            if (MmsVariableSpecification_isValueOfType(variable, value) == false) {
                 accessResults[i] = DATA_ACCESS_ERROR_TYPE_INCONSISTENT;
                 goto end_of_main_loop;
             }

src/vs/libiec61850-wo-goose.def

@@ -571,3 +571,4 @@ EXPORTS
     IedModel_getDeviceByInst
     MmsConnection_writeNamedVariableList
     IedConnection_writeDataSetValues
+    MmsVariableSpecification_isValueOfType

src/vs/libiec61850.def

@@ -652,3 +652,4 @@ EXPORTS
     SVClientASDU_hasRefrTm
     SVClientASDU_getRefrTmAsMs
     IedConnection_writeDataSetValues
+    MmsVariableSpecification_isValueOfType