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Diffstat (limited to 'net/ipv6/netfilter/ip6t_hl.c')
-rw-r--r--net/ipv6/netfilter/ip6t_hl.c80
1 files changed, 80 insertions, 0 deletions
diff --git a/net/ipv6/netfilter/ip6t_hl.c b/net/ipv6/netfilter/ip6t_hl.c
new file mode 100644
index 00000000000..0beaff5471d
--- /dev/null
+++ b/net/ipv6/netfilter/ip6t_hl.c
@@ -0,0 +1,80 @@
+/* Hop Limit matching module */
+
+/* (C) 2001-2002 Maciej Soltysiak <solt@dns.toxicfilms.tv>
+ * Based on HW's ttl module
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#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, unsigned int protoff,
+ 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 = {
+ .name = "hl",
+ .match = &match,
+ .checkentry = &checkentry,
+ .me = 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);