Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / netfilter / xt_length.c

diff --git a/kernel/net/netfilter/xt_length.c b/kernel/net/netfilter/xt_length.c
new file mode 100644 (file)
index 0000000..176e557
--- /dev/null
+++ b/kernel/net/netfilter/xt_length.c
@@ -0,0 +1,70 @@
+/* Kernel module to match packet length. */
+/* (C) 1999-2001 James Morris <jmorros@intercode.com.au>
+ *
+ * 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/ipv6.h>
+#include <net/ip.h>
+
+#include <linux/netfilter/xt_length.h>
+#include <linux/netfilter/x_tables.h>
+
+MODULE_AUTHOR("James Morris <jmorris@intercode.com.au>");
+MODULE_DESCRIPTION("Xtables: Packet length (Layer3,4,5) match");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("ipt_length");
+MODULE_ALIAS("ip6t_length");
+
+static bool
+length_mt(const struct sk_buff *skb, struct xt_action_param *par)
+{
+       const struct xt_length_info *info = par->matchinfo;
+       u_int16_t pktlen = ntohs(ip_hdr(skb)->tot_len);
+
+       return (pktlen >= info->min && pktlen <= info->max) ^ info->invert;
+}
+
+static bool
+length_mt6(const struct sk_buff *skb, struct xt_action_param *par)
+{
+       const struct xt_length_info *info = par->matchinfo;
+       const u_int16_t pktlen = ntohs(ipv6_hdr(skb)->payload_len) +
+                                sizeof(struct ipv6hdr);
+
+       return (pktlen >= info->min && pktlen <= info->max) ^ info->invert;
+}
+
+static struct xt_match length_mt_reg[] __read_mostly = {
+       {
+               .name           = "length",
+               .family         = NFPROTO_IPV4,
+               .match          = length_mt,
+               .matchsize      = sizeof(struct xt_length_info),
+               .me             = THIS_MODULE,
+       },
+       {
+               .name           = "length",
+               .family         = NFPROTO_IPV6,
+               .match          = length_mt6,
+               .matchsize      = sizeof(struct xt_length_info),
+               .me             = THIS_MODULE,
+       },
+};
+
+static int __init length_mt_init(void)
+{
+       return xt_register_matches(length_mt_reg, ARRAY_SIZE(length_mt_reg));
+}
+
+static void __exit length_mt_exit(void)
+{
+       xt_unregister_matches(length_mt_reg, ARRAY_SIZE(length_mt_reg));
+}
+
+module_init(length_mt_init);
+module_exit(length_mt_exit);