Am 11.07.2010 17:14, schrieb Michael S. Tsirkin: > diff --git a/extensions/libxt_CHECKSUM.c b/extensions/libxt_CHECKSUM.c > new file mode 100644 > index 0000000..00fbd8f > --- /dev/null > +++ b/extensions/libxt_CHECKSUM.c > @@ -0,0 +1,99 @@ > +/* Shared library add-on to xtables for CHECKSUM > + * > + * (C) 2002 by Harald Welte <laforge@xxxxxxxxxxxx> > + * (C) 2010 by Red Hat, Inc > + * Author: Michael S. Tsirkin <mst@xxxxxxxxxx> > + * > + * This program is distributed under the terms of GNU GPL v2, 1991 > + * > + * libxt_CHECKSUM.c borrowed some bits from libipt_ECN.c > + * > + * $Id$ Please no CVS IDs. > + */ > +#include <stdio.h> > +#include <string.h> > +#include <stdlib.h> > +#include <getopt.h> > + > +#include <xtables.h> > +#include <linux/netfilter/xt_CHECKSUM.h> > + > +static void CHECKSUM_help(void) > +{ > + printf( > +"CHECKSUM target options\n" > +" --checksum-fill Fill in packet checksum.\n"); > +} > + > +static const struct option CHECKSUM_opts[] = { > + { "checksum-fill", 0, NULL, 'F' }, > + { .name = NULL } > +}; > + > +static int CHECKSUM_parse(int c, char **argv, int invert, unsigned int *flags, > + const void *entry, struct xt_entry_target **target) > +{ > + struct xt_CHECKSUM_info *einfo > + = (struct xt_CHECKSUM_info *)(*target)->data; > + > + switch (c) { > + case 'F': > + if (*flags) > + xtables_error(PARAMETER_PROBLEM, > + "CHECKSUM target: Only use --checksum-fill ONCE!"); There is a helper function called xtables_param_act for checking double arguments and printing a standarized error message. > + einfo->operation = XT_CHECKSUM_OP_FILL; > + *flags |= XT_CHECKSUM_OP_FILL; > + break; > + default: > + return 0; > + } > + > + return 1; > +} > + -- To unsubscribe from this list: send the line "unsubscribe netfilter" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html