patch-2.4.21 linux-2.4.21/net/ipv6/netfilter/ip6t_hl.c

• Lines: 75
• Date: 2003-06-13 07:51:39.000000000 -0700
• Orig file: linux-2.4.20/net/ipv6/netfilter/ip6t_hl.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.20/net/ipv6/netfilter/ip6t_hl.c linux-2.4.21/net/ipv6/netfilter/ip6t_hl.c
@@ -0,0 +1,74 @@
+/*
+ * Hop Limit matching module
+ * Maciej Soltysiak <solt@dns.toxicfilms.tv>
+ * Based on HW's ttl module
+ *
+ * This software is distributed under the terms  GNU GPL
+ */
+
+#include <linux/module.h>
+#include <linux/skbuff.h>
+
+#include <linux/netfilter_ipv6/ip6t_hl.h>
+#include <linux/netfilter_ipv6/ip6_tables.h>
+
+MODULE_AUTHOR("Maciej Soltysiak <solt@dns.toxicfilms.tv>");
+MODULE_DESCRIPTION("IP tables Hop Limit matching module");
+MODULE_LICENSE("GPL");
+
+static int match(const struct sk_buff *skb, const struct net_device *in,
+		 const struct net_device *out, const void *matchinfo,
+		 int offset, const void *hdr, u_int16_t datalen,
+		 int *hotdrop)
+{
+	const struct ip6t_hl_info *info = matchinfo;
+	const struct ipv6hdr *ip6h = skb->nh.ipv6h;
+
+	switch (info->mode) {
+		case IP6T_HL_EQ:
+			return (ip6h->hop_limit == info->hop_limit);
+			break;
+		case IP6T_HL_NE:
+			return (!(ip6h->hop_limit == info->hop_limit));
+			break;
+		case IP6T_HL_LT:
+			return (ip6h->hop_limit < info->hop_limit);
+			break;
+		case IP6T_HL_GT:
+			return (ip6h->hop_limit > info->hop_limit);
+			break;
+		default:
+			printk(KERN_WARNING "ip6t_hl: unknown mode %d\n", 
+				info->mode);
+			return 0;
+	}
+
+	return 0;
+}
+
+static int checkentry(const char *tablename, const struct ip6t_ip6 *ip,
+		      void *matchinfo, unsigned int matchsize,
+		      unsigned int hook_mask)
+{
+	if (matchsize != IP6T_ALIGN(sizeof(struct ip6t_hl_info)))
+		return 0;
+
+	return 1;
+}
+
+static struct ip6t_match hl_match = { { NULL, NULL }, "hl", &match,
+		&checkentry, NULL, THIS_MODULE };
+
+static int __init init(void)
+{
+	return ip6t_register_match(&hl_match);
+}
+
+static void __exit fini(void)
+{
+	ip6t_unregister_match(&hl_match);
+
+}
+
+module_init(init);
+module_exit(fini);