diff --git a/io/channel-websock.c b/io/channel-websock.c
index 6ddcec1549..2258557a21 100644
--- a/io/channel-websock.c
+++ b/io/channel-websock.c
@@ -431,12 +431,12 @@ static void qio_channel_websock_handshake_process(QIOChannelWebsock *ioc,
         goto bad_request;
     }
 
-    if (!g_strrstr(connection, QIO_CHANNEL_WEBSOCK_CONNECTION_UPGRADE)) {
+    if (strcasecmp(connection, QIO_CHANNEL_WEBSOCK_CONNECTION_UPGRADE) != 0) {
         error_setg(errp, "No connection upgrade requested '%s'", connection);
         goto bad_request;
     }
 
-    if (!g_str_equal(upgrade, QIO_CHANNEL_WEBSOCK_UPGRADE_WEBSOCKET)) {
+    if (strcasecmp(upgrade, QIO_CHANNEL_WEBSOCK_UPGRADE_WEBSOCKET) != 0) {
         error_setg(errp, "Incorrect upgrade method '%s'", upgrade);
         goto bad_request;
     }