1 files changed, 102 insertions, 0 deletions
diff --git a/2003/netfilter-programming-clt2003/libipt_workshop.c b/2003/netfilter-programming-clt2003/libipt_workshop.c
new file mode 100644
index 0000000..6254334
--- /dev/null
+++ b/2003/netfilter-programming-clt2003/libipt_workshop.c
@@ -0,0 +1,102 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <getopt.h>
+#include <linux/netfilter_ipv4/ip_tables.h>
+#include <linux/netfilter_ipv4/ipt_workshop.h>
+
+static void help(void)
+{
+	printf(
+"workshop match v%s options:\n"
+"  --ttl	TTL value\n"
+, IPTABLES_VERSION);
+}
+
+static void init(struct ipt_entry_match *m, unsigned int *nfcache)
+{
+	/* caching not implemented yet */
+	*nfcache |= NFC_UNKNOWN;
+}
+
+static int parse(int c, char **argv, int invert, unsigned int *flags,
+		 const struct ipt_entry *entry, unsigned int *nfcache,
+		 struct ipt_entry_match **match)
+{
+	struct ipt_ws_info *info = (struct ipt_ws_info *) (*match)->data;
+
+	check_inverse(optarg, &invert, &optind, 0);
+
+	if (invert)
+		exit_error(PARAMETER_PROBLEM, "invert not supported");
+
+	if (*flags)
+		exit_error(PARAMETER_PROBLEM, 
+			   "workshop: can't specify parameter twice");
+
+	if (!optarg)
+		exit_error(PARAMETER_PROBLEM,
+			   "workshop: you must specify a value");
+
+	switch (c) {
+		case 'z':
+			info->ttl = atoi(optarg);
+			/* FIXME: range 0-255 */
+			*flags = 1;
+			break;
+		default:
+			return 0;
+	}
+
+	return 1;
+}
+
+static void final_check(unsigned int flags)
+{
+	if (!flags)
+		exit_error(PARAMETER_PROBLEM,
+			   "workshop match: you must specify foo");
+}
+
+static void print(const struct ipt_ip *ip,
+		  const struct ipt_entry_match *match,
+		  int numeric)
+{
+	const struct ipt_ws_info *info = (struct ipt_ws_info *) match->data;
+
+	printf("workshop match TTL=%u ", info->ttl);
+
+}
+
+static void save(const struct ipt_ip *ip,
+		 const struct ipt_entry_match *match)
+{
+	const struct ipt_ws_info *info = (struct ipt_ws_info *) match->data;
+
+	printf("--ttl %u ", info->ttl);
+}
+
+static struct option opts[] = {
+	{ "ttl", 1, 0, 'z' },
+	{ 0 }
+};
+
+static struct iptables_match ws = {
+	.next = NULL,
+	.name = "workshop",
+	.version = IPTABLES_VERSION,
+	.size = IPT_ALIGN(sizeof(struct ipt_ws_info)),
+	.userspacesize = IPT_ALIGN(sizeof(struct ipt_ws_info)),
+	.help = &help,
+	.init = &init,
+	.parse = &parse,
+	.final_check = &final_check,
+	.print = &print,
+	.save = &save,
+	.extra_opts = opts
+};
+
+void _init(void)
+{
+	register_match(&ws);
+}