avformat/http: Check that the protocol of redirects is http or https

Fixes: #YWH-PGM40646-10

Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libavformat/http.c

@@ -253,7 +253,11 @@ static int http_open_cnx_internal(URLContext *h, AVDictionary **options)
             if (err < 0)
                 goto end;
         }
+    } else if (strcmp(proto, "http")) {
+        err = AVERROR(EINVAL);
+        goto end;
     }
+
     if (port < 0)
         port = 80;