diff --git a/src/http.cpp b/src/http.cpp
index ecd8506..3e04c49 100644
--- a/src/http.cpp
+++ b/src/http.cpp
@@ -56,6 +56,14 @@ const Request http::parse_request(const string &request)
                 size = static_cast<uint16_t>(std::stoul(answer));
             }
         }
+        if (size > 512)
+        {
+            size = 512;
+        }
+        if (size < 1)
+        {
+            size = 1;
+        }
     }
 
     return { digest, size };