Major changes, this library isn't libnfnetlink_conntrack anymore.

We provide an high level interface that abstracts from the netlink
sockets. Now users don't need to know anything about them.

1 files changed, 65 insertions, 0 deletions

diff --git a/extensions/libnetfilter_conntrack_icmp.c b/extensions/libnetfilter_conntrack_icmp.c
new file mode 100644
index 0000000..38ad41a
--- /dev/null
+++ b/extensions/libnetfilter_conntrack_icmp.c
@@ -0,0 +1,65 @@
+/*
+ * (C) 2005 by Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ *      This program is free software; you can redistribute it and/or modify
+ *      it under the terms of the GNU General Public License as published by
+ *      the Free Software Foundation; either version 2 of the License, or
+ *      (at your option) any later version.
+ *
+ */
+#include <stdio.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <string.h>
+#include <netinet/in.h> /* For htons */
+#include <linux/netfilter/nfnetlink_conntrack.h>
+#include <libnetfilter_conntrack/libnetfilter_conntrack.h>
+
+void parse_proto(struct nfattr *cda[], struct nfct_tuple *tuple)
+{
+	if (cda[CTA_PROTO_ICMP_TYPE-1])
+		tuple->l4dst.icmp.type =
+			*(u_int8_t *)NFA_DATA(cda[CTA_PROTO_ICMP_TYPE-1]);
+
+	if (cda[CTA_PROTO_ICMP_CODE-1])
+		tuple->l4dst.icmp.code =
+			*(u_int8_t *)NFA_DATA(cda[CTA_PROTO_ICMP_CODE-1]);
+
+	if (cda[CTA_PROTO_ICMP_ID-1])
+		tuple->l4src.icmp.id =
+			*(u_int16_t *)NFA_DATA(cda[CTA_PROTO_ICMP_ID-1]);
+}
+
+int print_proto(char *buf, struct nfct_tuple *t)
+{
+	int size = 0;
+	
+	size += sprintf(buf, "type=%d code=%d ", t->l4dst.icmp.type,
+					         t->l4dst.icmp.code);
+	/* ID only makes sense with ECHO */
+	if (t->l4dst.icmp.type == 8)
+		size += sprintf(buf, "id=%d ", t->l4src.icmp.id);
+
+	return size;
+}
+
+static struct nfct_proto icmp = {
+	.name 			= "icmp",
+	.protonum		= IPPROTO_ICMP,
+	.parse_proto		= parse_proto,
+	.print_proto		= print_proto,
+	.version		= LIBNETFILTER_CONNTRACK_VERSION
+};
+
+void __attribute__ ((constructor)) init(void);
+void __attribute__ ((destructor)) fini(void);
+
+void init(void)
+{
+	nfct_register_proto(&icmp);
+}
+
+void fini(void)
+{
+	nfct_unregister_proto(&icmp);
+}