- MMS client: improved handling of malformed messages when receiving reports

- MMS client: fixed potential memory leak when receiving malformed messages

src/iec61850/client/client_report.c

@@ -43,6 +43,8 @@ struct sClientReport
     char* dataSetName;
     int dataSetNameSize; /* size of the dataSetName buffer */
 
+    int dataSetSize;
+
     MmsValue* entryId;
     MmsValue* dataReferences;
     MmsValue* dataSetValues;
@@ -93,6 +95,8 @@ ClientReport_create()
 {
     ClientReport self = (ClientReport) GLOBAL_CALLOC(1, sizeof(struct sClientReport));
 
+    self->dataSetSize = -1;
+
     return self;
 }
 
@@ -607,6 +611,18 @@ private_IedConnection_handleReport(IedConnection self, MmsValue* value)
 
     int dataSetSize = MmsValue_getBitStringSize(inclusion);
 
+    if (matchingReport->dataSetSize == -1) {
+        matchingReport->dataSetSize = dataSetSize;
+    }
+    else {
+        if (dataSetSize != matchingReport->dataSetSize) {
+            if (DEBUG_IED_CLIENT)
+                printf("IED_CLIENT: received malformed report (inclusion has no plausible size)\n");
+
+            goto exit_function;
+        }
+    }
+
     int includedElements = MmsValue_getNumberOfSetBits(inclusion);
 
     if (DEBUG_IED_CLIENT)

src/iec61850/client/ied_connection.c

@@ -437,6 +437,7 @@ informationReportHandler(void* parameter, char* domainName,
     if (DEBUG_IED_CLIENT)
         printf("DEBUG_IED_CLIENT: received information report for %s\n", variableListName);
 
+    if (value) {
         if (domainName == NULL) {
 
             if (isVariableListName) {
@@ -471,6 +472,7 @@ informationReportHandler(void* parameter, char* domainName,
 
         MmsValue_delete(value);
     }
+}
 
 static IedConnection
 createNewConnectionObject(TLSConfiguration tlsConfig)

src/mms/iso_mms/client/mms_client_get_var_access.c

@@ -138,8 +138,7 @@ mmsClient_parseGetVariableAccessAttributesResponse(ByteBuffer* message, uint32_t
     asn_dec_rval_t rval = ber_decode(NULL, &asn_DEF_MmsPdu,
             (void**) &mmsPdu, ByteBuffer_getBuffer(message), ByteBuffer_getSize(message));
 
-    if (rval.code != RC_OK)
-        return NULL;
+    if (rval.code == RC_OK) {
 
         if (mmsPdu->present == MmsPdu_PR_confirmedResponsePdu) {
 
@@ -157,6 +156,7 @@ mmsClient_parseGetVariableAccessAttributesResponse(ByteBuffer* message, uint32_t
                 typeSpec = createTypeSpecification(asnTypeSpec);
             }
         }
+    }
 
     asn_DEF_MmsPdu.free_struct(&asn_DEF_MmsPdu, mmsPdu, 0);
 

src/mms/iso_mms/common/mms_value.c

@@ -1190,6 +1190,9 @@ MmsValue_deleteIfNotNull(MmsValue* self)
 void
 MmsValue_delete(MmsValue* self)
 {
+    if (self == NULL)
+        return;
+
     switch (self->type)
     {
     case MMS_INTEGER: