diff --git a/src/image.c b/src/image.c
index 16009ed..7284a3d 100644
--- a/src/image.c
+++ b/src/image.c
@@ -248,7 +248,11 @@ void do_upload(char *filename){
         CborEncoder root, map;
         uint8_t cbor_buf[BOOT_SERIAL_OUT_MAX*2];
         cbor_encoder_init(&root, cbor_buf, BOOT_SERIAL_OUT_MAX*2, 0);
+#ifdef DO_UPLOAD_SHA
         cbor_encoder_create_map(&root, &map, pos == 0 ? 4 : 2);
+#else
+        cbor_encoder_create_map(&root, &map, pos == 0 ? 3 : 2);
+#endif
 
         cbor_encode_text_stringz(&map, "data");
         uint8_t data[data_chunk_len];
@@ -269,6 +273,7 @@ void do_upload(char *filename){
         cbor_encode_text_stringz(&map, "off");
         cbor_encode_uint(&map, pos);
 
+#ifdef DO_UPLOAD_SHA
         if (pos == 0) {
             cbor_encode_text_stringz(&map, "sha");
             int f = open(filename, O_RDONLY);
@@ -292,6 +297,7 @@ void do_upload(char *filename){
             sha256_final(&sha_ctx, (BYTE *)&sha);
             cbor_encode_byte_string(&map, sha, 32);
         }
+#endif /* DO_UPLOAD_SHA */
 
         cbor_encoder_close_container(&root, &map);
         size_t cbor_size = cbor_encoder_get_buffer_size(&root, cbor_buf);