check_tcp.c - Validate sent data size

my_send() and send() do not validate the amount sent, but only return -1 or bytes sent. Since we are sending via a single send command, all of the send string should be sent in a single command and should be checked against the sent amount. We could also just check for -1, however that is less accurate as the server would never see the rest of the string and may have unexpected results if the entirety is not sent.

coverity 103712

plugins/check_tcp.c

@@ -253,8 +253,8 @@ main (int argc, char **argv)
 	}
 #endif /* HAVE_SSL */
 
-	if (server_send != NULL) {		/* Something to send? */
-		my_send(server_send, strlen(server_send));
+	if (server_send != NULL &&  strlen(server_send) > my_send(server_send, strlen(server_send))) {		/* Something to send? and validate return*/
+		die(STATE_UNKNOWN, "%s - %s", _("No data sent to host"), strerror(errno));
 	}
 
 	if (delay > 0) {