/* IP tables module for matching the value of the IPv4 and TCP ECN bits
- *
- * ipt_ecn.c,v 1.3 2002/05/29 15:09:00 laforge Exp
*
* (C) 2002 by Harald Welte <laforge@gnumonks.org>
*
* published by the Free Software Foundation.
*/
+#include <linux/in.h>
+#include <linux/ip.h>
+#include <net/ip.h>
#include <linux/module.h>
#include <linux/skbuff.h>
#include <linux/tcp.h>
+#include <linux/netfilter/x_tables.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv4/ipt_ecn.h>
MODULE_AUTHOR("Harald Welte <laforge@netfilter.org>");
-MODULE_DESCRIPTION("iptables ECN matching module");
+MODULE_DESCRIPTION("Xtables: Explicit Congestion Notification (ECN) flag match for IPv4");
MODULE_LICENSE("GPL");
-static inline int match_ip(const struct sk_buff *skb,
- const struct ipt_ecn_info *einfo)
+static inline bool match_ip(const struct sk_buff *skb,
+ const struct ipt_ecn_info *einfo)
{
- return ((skb->nh.iph->tos&IPT_ECN_IP_MASK) == einfo->ip_ect);
+ return (ip_hdr(skb)->tos & IPT_ECN_IP_MASK) == einfo->ip_ect;
}
-static inline int match_tcp(const struct sk_buff *skb,
- const struct ipt_ecn_info *einfo,
- int *hotdrop)
+static inline bool match_tcp(const struct sk_buff *skb,
+ const struct ipt_ecn_info *einfo,
+ bool *hotdrop)
{
- struct tcphdr _tcph, *th;
+ struct tcphdr _tcph;
+ const struct tcphdr *th;
/* In practice, TCP match does this, so can't fail. But let's
* be good citizens.
*/
- th = skb_header_pointer(skb, skb->nh.iph->ihl * 4,
- sizeof(_tcph), &_tcph);
+ th = skb_header_pointer(skb, ip_hdrlen(skb), sizeof(_tcph), &_tcph);
if (th == NULL) {
- *hotdrop = 0;
- return 0;
+ *hotdrop = false;
+ return false;
}
if (einfo->operation & IPT_ECN_OP_MATCH_ECE) {
if (einfo->invert & IPT_ECN_OP_MATCH_ECE) {
if (th->ece == 1)
- return 0;
+ return false;
} else {
if (th->ece == 0)
- return 0;
+ return false;
}
}
if (einfo->operation & IPT_ECN_OP_MATCH_CWR) {
if (einfo->invert & IPT_ECN_OP_MATCH_CWR) {
if (th->cwr == 1)
- return 0;
+ return false;
} else {
if (th->cwr == 0)
- return 0;
+ return false;
}
}
- return 1;
+ return true;
}
-static int match(const struct sk_buff *skb,
- const struct net_device *in, const struct net_device *out,
- const struct xt_match *match, const void *matchinfo,
- int offset, unsigned int protoff, int *hotdrop)
+static bool
+ecn_mt(const struct sk_buff *skb, const struct net_device *in,
+ const struct net_device *out, const struct xt_match *match,
+ const void *matchinfo, int offset, unsigned int protoff, bool *hotdrop)
{
const struct ipt_ecn_info *info = matchinfo;
if (info->operation & IPT_ECN_OP_MATCH_IP)
if (!match_ip(skb, info))
- return 0;
+ return false;
if (info->operation & (IPT_ECN_OP_MATCH_ECE|IPT_ECN_OP_MATCH_CWR)) {
- if (skb->nh.iph->protocol != IPPROTO_TCP)
- return 0;
+ if (ip_hdr(skb)->protocol != IPPROTO_TCP)
+ return false;
if (!match_tcp(skb, info, hotdrop))
- return 0;
+ return false;
}
- return 1;
+ return true;
}
-static int checkentry(const char *tablename, const void *ip_void,
- const struct xt_match *match,
- void *matchinfo, unsigned int hook_mask)
+static bool
+ecn_mt_check(const char *tablename, const void *ip_void,
+ const struct xt_match *match, void *matchinfo,
+ unsigned int hook_mask)
{
const struct ipt_ecn_info *info = matchinfo;
const struct ipt_ip *ip = ip_void;
if (info->operation & IPT_ECN_OP_MATCH_MASK)
- return 0;
+ return false;
if (info->invert & IPT_ECN_OP_MATCH_MASK)
- return 0;
+ return false;
if (info->operation & (IPT_ECN_OP_MATCH_ECE|IPT_ECN_OP_MATCH_CWR)
&& ip->proto != IPPROTO_TCP) {
printk(KERN_WARNING "ipt_ecn: can't match TCP bits in rule for"
" non-tcp packets\n");
- return 0;
+ return false;
}
- return 1;
+ return true;
}
-static struct ipt_match ecn_match = {
+static struct xt_match ecn_mt_reg __read_mostly = {
.name = "ecn",
- .match = match,
+ .family = AF_INET,
+ .match = ecn_mt,
.matchsize = sizeof(struct ipt_ecn_info),
- .checkentry = checkentry,
+ .checkentry = ecn_mt_check,
.me = THIS_MODULE,
};
-static int __init ipt_ecn_init(void)
+static int __init ecn_mt_init(void)
{
- return ipt_register_match(&ecn_match);
+ return xt_register_match(&ecn_mt_reg);
}
-static void __exit ipt_ecn_fini(void)
+static void __exit ecn_mt_exit(void)
{
- ipt_unregister_match(&ecn_match);
+ xt_unregister_match(&ecn_mt_reg);
}
-module_init(ipt_ecn_init);
-module_exit(ipt_ecn_fini);
+module_init(ecn_mt_init);
+module_exit(ecn_mt_exit);