Handle to: destination length to detect a null contract address

src_common/ethUstream.c

@@ -202,6 +202,7 @@ static void processTo(txContext_t *context) {
                    copySize);
     }
     if (context->currentFieldPos == context->currentFieldLength) {
+        context->content->destinationLength = context->currentFieldLength;
         context->currentField++;
         context->processingField = false;
     }

src_common/ethUstream.h

@@ -51,6 +51,7 @@ typedef struct txContent_t {
     txInt256_t startgas;
     txInt256_t value;
     uint8_t destination[20];
+    uint8_t destinationLength;
 } txContent_t;
 
 typedef struct txContext_t {